Academic literature on the topic 'Organic compound content'

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Journal articles on the topic "Organic compound content"

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Šimon, T. "Aliphatic compounds, organic C and N and microbial biomass and its activity in long-term field experiment." Plant, Soil and Environment 51, No. 6 (November 19, 2011): 276–82. http://dx.doi.org/10.17221/3586-pse.

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The content of aliphatic compounds, hydrophobicity index, organic C and N content and the microbial biomass and respiration activity were analysed in soil samples originating from different plots of a long-term field experiment (variants: nil, NPK – mineral fertilization: 64.6–100 kg/ha/year, FYM – farmyard manure and FYM + NPK) from three blocks (III, IV and B) with different crop rotation. Samples were taken from 0–200 mm layer in 2002 and 2003 (spring and autumn). The plots without any fertilization had the significantly lowest aliphatic compound content compared to variants fertilized by FYM or FYM + NPK in all the evaluated blocks in both years. The variants fertilized only by mineral NPK without any organic fertilization had the slightly increased aliphatic compound content but they did not exceed significantly the control variants in most cases. The aliphatic compound contents correlated significantly with the organic C contents in 2002 and 2003, as well. The values of the hydrophobicity index showed a similar trend like the data mentioned above. Organic manure increased the soil organic nitrogen content, similarly to the carbon content. In variants fertilized by FYM and FYM + NPK the higher microbial biomass content was found comparing to unfertilized variants. Correlations between aliphatic compound content and biomass differed in spring (2002: r = 0.065, 2003: r = 0.068) and autumn (2002: r = 0.407, 2003: r = 0.529). Organically fertilized variants had increased basal respiration, in autumn 2002 the basal respiration was higher in variants fertilized by mineral NPK, too. The highest specific respiration was recorded in the unfertilised plot in block B (autumn 2002 and 2003), where low microbial biomass exhibited high activity. Increased specific respiration was found also in plots fertilized by FYM and FYM + NPK (block III and IV, autumn samplings). Positive significant correlations between microbial biomass content and basal respiration were found in 2002 (spring: r = 0.716) and 2003 (spring: r = 0.765, autumn: r = 0.671).
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Luo, Qiao, Jing Wang, JianHui Wang, Yu Shen, Peng Yan, YouPeng Chen, and ChengCheng Zhang. "Fate and Occurrence of Pharmaceutically Active Organic Compounds during Typical Pharmaceutical Wastewater Treatment." Journal of Chemistry 2019 (April 8, 2019): 1–12. http://dx.doi.org/10.1155/2019/2674852.

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The chemical composition, distribution, and fate of pharmaceutically active compounds (PhACs) present in typical pharmaceutical wastewater treatment plants were investigated with the aim of effectively removing these pollutants while minimizing waste of resources and energy. The results of this study indicate that the relative content of an organic compound class is unrelated to the number of organic compounds in the influent and effluent, yet it is directly proportional to the pollution contribution in pharmaceutical wastewater. In wastewater influent, the organic compound classes with the highest relative contents and pollution contributions were acids (relative content = 63.65%, contribution to pollution = 67.22%), esters (44.96%, 41.24%), and heterocyclic compounds (30.24%, 35.23%); in wastewater effluent, these classes were organic acids (62.54%, 65.13%), esters (52.66%, 59.02%), and organosilicon compounds (42.46%, 37.45%). The different physicochemical characteristics of these pollutants result in different removal efficiencies. For example, N,N-dimethylformamide, 4-methyloctane, N-ethylmorpholine, and 4-amino-N,N- and N,N-diethylbenzamide are refractory and are not degraded by microorganisms; thus, these compounds are discharged into the aquatic environment. Other organic compound classes including organosilicon compounds, acids, esters, heterocycles, and alcohols are mostly biodegraded, which leads to high concentrations of hydrocarbons in the wastewater effluent. The results of this study provide a foundation for the improvement of pharmaceutical wastewater treatment.
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Schwarzenbach, R. P., and J. Westall. "Sorption of Hydrophobic Trace Organic Compounds in Groundwater Systems." Water Science and Technology 17, no. 9 (September 1, 1985): 39–55. http://dx.doi.org/10.2166/wst.1985.0081.

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Factors influencing the subsurface sorption behavior of neutral and ionizable trace organic compounds are discussed. At equilibrium, the sorption of a neutral hydrophobic organic compound can be expressed by a simple partition coefficient. Partition coefficients, and thus retardation factors, may be estimated from the octanol/water partition coefficient of the compound and the organic carbon content of the aquifer material, if the organic carbon content exceeds 0.1%. For ionizable (anionic) hydrophobic compounds (represented by chlorinated phenols), the distribution ratio depends on both the pH and ionic strength of the aqueous phase, in contrast to the partitioning model for neutral compounds in which the composition of the aqueous phase is relatively unimportant.
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Cvetković, Biljana, Aleksandra Bajić, Miona Belović, Lato Pezo, Danka Dragojlović, Olivera Šimurina, Marijana Djordjević, Karin Korntheuer, Christian Philipp, and Reinhard Eder. "Assessing Antioxidant Properties, Phenolic Compound Profiles, Organic Acids, and Sugars in Conventional Apple Cultivars (Malus domestica): A Chemometric Approach." Foods 13, no. 14 (July 20, 2024): 2291. http://dx.doi.org/10.3390/foods13142291.

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This study analyzed the phenolic compounds, organic acids, sugars, and antioxidant activity in different conventional apple cultivars (Malus domestica) from the Serbian market. Polyphenol profiles, sugars, and organic acid contents were analyzed by HPLC, and antioxidant activity was examined by DPPH and FRAP. Notable findings included variations in phenolic compound presence, with certain compounds detected only in specific cultivars. ‘Red Jonaprince’ exhibited the highest arbutin (0.86 mg/kg FW) and quercetin-3-rhamnoside content (22.90 mg/kg FW), while ‘Idared’ stood out for its gallic acid content (0.22 mg/kg FW) and ‘Granny Smith’ for its catechin levels (21.19 mg/kg FW). Additionally, malic acid dominated among organic acids, with ‘Granny Smith’ showing the highest content (6958.48 mg/kg FW). Fructose was the predominant sugar across all cultivars. Chemometric analysis revealed distinct groupings based on phenolic and organic acid profiles, with ‘Granny Smith’ and ‘Golden Delicious’ exhibiting unique characteristics. Artificial neural network modeling effectively predicted antioxidant activity based on the input parameters. Global sensitivity analysis highlighted the significant influence of certain phenolic compounds and organic acids on antioxidant activity.
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Jiao, Huiying, Sijia Wu, Jingming Li, and Yanxin Sun. "Effects of Pelletized and Coated Organic Fertilizers on Flavor Compounds of Tomato Fruits and Leaves." Foods 13, no. 11 (May 25, 2024): 1653. http://dx.doi.org/10.3390/foods13111653.

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The application of organic fertilizers is one of the most important agricultural measures aimed at improving the flavor and productivity of Lycopersicon esculentum, with the granulation and coating of organic fertilizers, which can reduce seepage losses of great significance to the ecosystem. In this study, Jingcai 8 tomato was selected as the test material. Headspace solid-phase microextraction and gas chromatography–mass spectrometry (HS-SPME-GC-MS) methods were used to investigate the effects of different pelletized organic fertilizers and various coating materials on the flavor profile of the tomatoes. The results indicated that 67 volatile organic compounds (VOCs) were identified in the tomato fruits and 62 volatile compounds were identified in the leaves under different fertilizer treatments. The volatile compound content of the fruits in the BP treatment group was 35.38 μg/g, which was higher than that in other treatment groups, and the volatile compound content of the leaves was lower. A differential compound analysis with log2|fold change| ≥ 1 and variable important in projection (VIP) > 1 highlighted styrene, 3-methyl-1-butanol, and (E, E)-2,4-hexadienal as the major up-regulated compounds and methyl salicylate as the major down-regulated compound in the tomato fruit BCK (control) vs. BP. Moreover, the α-phellandrene content decreased in the tomato leaves. In addition, an analysis of the tomato fruit differential compounds and compounds with odor activity values (OAV) of ≥ 1, considering the OAV values of characteristic aroma compounds, identified key compounds affecting the flavor of the tomato fruits under the BP treatment. These included 2-nonenal, (E)-2-pentylfuran, trans-β-ionone, 1-penten-3-one, (E, E)-2,4-hexadienal, and 3-hexenol (fruity, floral, and herbaceous odors), (E, E)-2,4-heptadienal (fatty odor), and hexanal (green odor). The combined results analysis of the volatile compound content, differential compounds, and OAV values of characteristic aroma compounds aimed to clarify that the BP treatment group, which applied pelletized, large-grain organic fertilizer with polyurethane (pozzolanic + small-grain oil-coated + 2% paraffinic + 4% polyurethane) as a coating material, proved to be most effective in influencing the flavor of the tomato fruits. This finding lays the foundation for its potential commercial application in artificial orchards.
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Du, Yaxiao, Xuebin Xu, Fei Ma, and Changwen Du. "Solvent-Free Synthesis of Iron-Based Metal-Organic Frameworks (MOFs) as Slow-Release Fertilizers." Polymers 13, no. 4 (February 13, 2021): 561. http://dx.doi.org/10.3390/polym13040561.

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Metal-organic frameworks (MOFs) were usually synthesized in hydrothermal conditions; in this study, a more energy-saving, easier to control, and solvent-free mechanochemical method was firstly applied to synthesize MOFs with varied reactants as slow release fertilizer, and the components and structures were characterized by X-ray diffraction (XRD), Fourier transform infrared total attenuated reflectance (FTIR-ATR), and laser-induced breakdown spectroscopy (LIBS). Results showed that three MOFs (compounds I, II, and III) were obtained, the MOFs were confirmed as oxalate phosphate oxalate frameworks (OPA-MOF), and ions were adsorbed between layers that contributed to the contents, while urea molecules mainly impacted the structure. The elemental compositions significantly varied among the three compounds; compound I showed the highest content of N (4.91%), P (15.71%), and Fe (18.60%), compound III indicated the highest content of C (6.52%) and K (12.59%), while the contents of C, K, P, and Fe in compound II were in the medium range. Similar release profiles of Fe and P were found among the three MOFs, and the release rates of nutrients were demonstrated as the order of N > K > P > Fe. The compositions and release profiles demonstrated potential application of MOFs as a novel slow-release fertilizer.
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Prasetiyo, Himawan, Sri Purwaningsih, Iriani Setyaningsih, Mala Nurilmala, Uju Uju, and Kustiyariah Tarman. "Off-odour Identification from Volatile Organic Compounds (VOCs) of Spirulina." BIO Web of Conferences 92 (2024): 02006. http://dx.doi.org/10.1051/bioconf/20249202006.

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Spirulina platensis is a common cyanobacteria microalga with high nutrition and bioactive compound sources. The addition of spirulina in foods and beverages improves nutrition and bioactive compound content. However, certain species of cyanobacteria are known to produce various compounds causing off-odour. This study investigates the chemical profile and volatile organic compounds (VOCs) in spirulina biomass and determine off-odour potency. The spirulina extract was analysed phytochemical qualitatively and GC-MS (Gas Chromatography-Mass Spectrometry). The Spectra mass was compared to the mass spectral database and profile of chemical compound libraries. The result shows, phytochemical analysis positively contains of alkaloids, flavonoids, tannins, saponins, and terpenoids. A total of 155 volatile compounds consisting of classes acid, alcohol, aldehyde, alkene, benzene, ether, ester, ketone, sulphur-contain, and terpene were identified. The off-odour VOC content such as phytol; cyclopropanebutanoic acid, 2- [[2 - [[2 - [(2- pentylcyclopropyl) methyl) cyclopropyl) methyl) cyclopropyl) methyl]-, methyl ester; 3.7.11.15-tetramethyl-2-hexadecen-1-ol; Imidazole, 2-fluoro-5-(2-carboxyvinyl)-; β-ionone; and N,N-Dimethyl-O-(1-methyl-butyl)-hydroxylamine, were detected in spirulina. The odour descriptions of off-odour VOCs are floral, balsamic, powdery, waxy, rancid, sweaty, woody, alkali, and fish-like. The off-odour content of VOCs might influence food's sensory odour, with spirulina added in excessive quantities.
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Zheng, Tingting, Shu Wang, Mengyao Wang, Jiao Mao, Yuanmeng Xu, Jiangling Ren, Yuhan Liu, Sichen Liu, Zhijun Qiao, and Xiaoning Cao. "Effect of Different Fertilizer Types on Quality of Foxtail Millet under Low Nitrogen Conditions." Plants 13, no. 13 (July 3, 2024): 1830. http://dx.doi.org/10.3390/plants13131830.

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In order to clarify the effect of different fertilizers on foxtail millet quality under low nitrogen conditions, we used JGNo.21 and LZGNo.2 as experimental materials and set up five treatments, including non-fertilization, nitrogen, phosphorus, compound, and organic fertilizers, to study the regulation of different fertilizer types on agronomic traits, nutrient fractions, and pasting characteristics of foxtail millet under low nitrogen conditions. Compared with the control, all of the fertilizers improved the agronomic traits of JGNo.21 to a certain extent. Nitrogen and compound fertilizer treatments reduced the starch content of JGNo.21; the starch content was reduced by 0.55% and 0.07% under nitrogen and compound fertilizers treatments. Phosphorus and organic fertilizers increased starch content, and starch content increased by 0.50% and 0.56% under phosphorus and organic fertilizer treatments. The effect of each fertilizer treatment on protein content was completely opposite to that of starch; different fertilizer treatments reduced the fat content of JGNo.21 and increased the fiber content. Among them, nitrogen and phosphorus fertilizers increased the yellow pigment content; the yellow pigment content increased by 1.21% and 2.64% under nitrogen and phosphorus fertilizer treatments. Organic and compound fertilizers reduced the content of yellow pigment; the yellow pigment content was reduced by 3.36% and 2.79% under organic and compound fertilizer treatments. Nitrogen and organic fertilizers increased the fat content of LZGNo.2; the fat content increased by 2.62% and 1.98% under nitrogen, organic fertilizer treatment. Compound and phosphorus fertilizer decreased the fat content; the fat content decreased by 2.16% and 2.90% under compound and phosphorus fertilizer treatment. Different fertilizer treatments reduced the cellulose and yellow pigment content of LZGNo.2. The content of essential, non-essential, and total amino acids of JGNo.21 was increased under compound and nitrogen fertilizer treatments and decreased under organic and phosphorus fertilizer treatments. The content of essential, non-essential, and total amino acids of LZGNo.2 was significantly higher under compound, nitrogen, and organic fertilizer treatments compared with control and significantly decreased under phosphorus fertilizer treatments. Nitrogen and compound fertilizer treatments significantly reduced the values of peak viscosity, trough viscosity, breakdown viscosity, final viscosity, setback viscosity, and pasting time of each index of JGNo.21; phosphorus and organic fertilizer treatments improved the values of each index. In contrast, the pasting viscosity of LZGNo.2 increased under phosphorus fertilizer treatment and decreased under nitrogen fertilizer treatment. Reasonable fertilization can improve the quality of foxtail millet, which provides a scientific theoretical basis for improving the quality of foxtail millet.
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Miklavčič Višnjevec, Ana, Paul Baker, Adam Charlton, Dave Preskett, Kelly Peeters, Črtomir Tavzes, Katja Kramberger, and Matthew Schwarzkopf. "Developing an Olive Biorefinery in Slovenia: Analysis of Phenolic Compounds Found in Olive Mill Pomace and Wastewater." Molecules 26, no. 1 (December 22, 2020): 7. http://dx.doi.org/10.3390/molecules26010007.

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The valorization of olive pomace through the extraction of phenolic compounds at an industrial scale is influenced by several factors that can have a significant impact on the feasibility of this approach. These include the types and levels of phenolic compounds that are present, the impact that seasonal variation and cultivar type have on the phenolic compound content in both olive pomace and mill effluents and the technological approach used to process the olive crop. Chemical analysis of phenolic compounds was performed using an HPLC-diode-array detector (DAD)-qTOF system, resulting in the identification of 45 compounds in olive mill wastewater and pomace, where secoiridoids comprised 50–60% of the total phenolic content. This study examined three different factors that could impact the phenolic compound content of these processing streams, including cultivar types typically grown on local farms in Slovenia, the type of downstream processing used and seasonality effects. Olive crop varieties sourced from local farms showed high variability, and the highest phenolic content was associated with the local variety “Istrska Belica”. During processing, the phenolic content was on average approximately 50% higher during two-phase decanting compared to three-phase decanting and the type of compound present significantly different. An investigation into the seasonal effects revealed that the phenolic content was 20% higher during the 2019 growing season compared to 2018. A larger sample size over additional growing seasons is required to fully understand the annual variation in phenolic compound content. The methods and results used in this study provide a basis for further analysis of phenolic compounds present in the European Union’s olive crop processing residues and will inform techno-economic modelling for the development of olive biorefineries in Slovenia.
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Simkova, Kristyna, Robert Veberic, Mariana Cecilia Grohar, Massimiliano Pelacci, Tina Smrke, Tea Ivancic, Aljaz Medic, Nika Cvelbar Weber, and Jerneja Jakopic. "Changes in the Aroma Profile and Phenolic Compound Contents of Different Strawberry Cultivars during Ripening." Plants 13, no. 10 (May 20, 2024): 1419. http://dx.doi.org/10.3390/plants13101419.

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Secondary metabolites, namely, phenolic and volatile organic compounds, contribute to the nutritional and organoleptic quality of the strawberry fruit. This study focuses on the changes in the content of phenolic compounds and volatile organic compounds during the ripening, from green to overripe fruit, of five strawberry cultivars (‘Asia’, ‘CIVN 766’, ‘Aprica’, ‘Clery’, and ‘Malwina’). Additionally, these changes are compared with the colour of the fruit and peroxidase and polyphenol oxidase activity. Our results show that the accumulation of secondary metabolites (phenolic and volatile organic compounds) significantly changed during the ripening process for all of the studied cultivars. As for phenolic compounds, flavanols and hydroxybenzoic acid derivatives comprised between 87 and 95% of the total phenolic compound content in unripe green fruit. In contrast, anthocyanins and hydroxycinnamic acid derivatives comprised between 64 and 77% of the total phenolic compound content in overripe fruit, except in the fruit of the cultivar ‘CIVN766’. When it comes to the aroma profile, the content of aldehydes decreased by 24–49% as the fruit ripened, and the accumulation of esters increased. Our study also shows that the ripening process differs among cultivars, and it is therefore necessary to define ripening indicators separately for each cultivar.
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Dissertations / Theses on the topic "Organic compound content"

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Szecsödy, James Edward. "Sorption Kinetics of Hydrophobic Organic Compounds onto Organic Modified Surfaces." Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/219433.

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The sorption of five chlorinated benzenes and sixteen other organic solutes was investigated by determining the extent of sorption and the sorption rates in a series of 40 batch and 139 column experiments using surface-modified silica of known chemical composition. These surfaces were used to represent important functional groups in soil, and consisted of porous silica with patchy surface coatings of aliphatic chains (C₁, C₈, and C₁₈), and other substituent groups (phenyl, amine, alcoholic, and carboxylic). Three possible rate-limiting steps were examined: diffusion through immobile pore fluid, diffusion through bound organic matter, and the chemical binding and release rate. First-order desorption rate coefficients were observed to be 10⁻¹ to 10⁻² s⁻¹ on unbonded, and C₈, C₁₈, amine, and alcoholic modified surfaces, and 10⁻³ to 10⁻⁵ s⁻¹ on C₁ and phenyl-polymer modified surfaces. Diffusion through immobile pore fluid had only a minor effect on the sorption rate, as evidenced by similar rates on organic-bound porous and solid particles. The diffusion rate through the bound organic layer is not rate limiting due to the small organic layer thickness. The observed slow desorption on the phenyl-polymer surface is consistent with the rate limiting step being the chemical binding and release rate. The changes in the rate with temperature and within a series of chlorinated benzenes support this conclusion. The free energies for sorption onto the phenyl-polymer surface ranged from -4.0 kcal mol⁻¹ for chlorobenzene to -6.9 kcal mol⁻¹ for pentachlorobenzene, which are within the range expected for van der Waals interactions. The observed sorption energies are slightly stronger than predicted for hydrophobic surfaces, possibly reflecting strong binding due to multiple pi-pi electron interactions on the phenyl-polymer surface. Hydrophobic solute partitioning onto natural soils, as observed by others, is less than that observed on aliphatic and phenyl hydrophobic surfaces in this study, but greater than on amine or alcoholic modified surfaces. The sorption of di-, tri-, and tetra-chlorobenzenes onto the phenyl-polymer surface is apparently driven by the overall sorption enthalpy (ΔH° = -3.9 to -4.9 kcal mo1⁻¹) and to a lesser extent by the entropy (TΔS° = 0.5 to 1.5 kcal mol⁻¹). As equilibrium of the reactions observed in this study are reached within hours, these reactions are important at small field scales where residence times are hundreds of hours or less.
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Gonsior, Michael, and n/a. "Dissolved organic matter in New Zealand natural waters." University of Otago. Department of Chemistry, 2008. http://adt.otago.ac.nz./public/adt-NZDU20080501.114023.

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Dissolved organic matter (DOM) is the most dynamic and least understood part of the global oceanic carbon cycle. Furthermore the molecular composition of DOM is largely unknown. This study focused on the distribution pattern, removal processes and molecular characterisation of DOM in a range of estuaries and coastal zones in New Zealand. Doubtful Sound, the longest fjord in Fiordland National Park, South Island, New Zealand was of particular interest, because of the combination of extreme rainfall, enhanced production of DOM within the temperate rainforest which largely appears in the relatively deep ([greater than or equal to] 5 m) low salinity layer (LSL) at the fjord surface. A typical river estuary (Freshwater River) located in Stewart Island, New Zealand was also investigated. Optical water properties such as the UV/Vis absorption coefficient at 355 nm (a[CDOM](355)) and excitation-emission matrix fluorescence (EEM) were determined for samples from freshwater, across the LSL into open ocean water. These optical properties showed a marked decrease with salinity and highest levels of EEM fluorescence and a[CDOM] (355) in the brackish surface water. In addition to the observed changes in the optical properties, ultrahigh resolution Electrospray Ionisation Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (ESI-FT-ICR-MS) determination of molecular formulae revealed that in the fjord about 20 % of these formulae changed along a vertical salinity gradient across the LSL between the brackish surface water and the saline water at 5 m depth. This trend was even more pronounced along the salinity gradient of the Fresh Water River Estuary in Stewart Island, where 60 % of all assigned molecular masses changed from freshwater over the mixing zone to ocean water. Associated with these changes was a marked increase in aromaticity with increasing salinity. Comparable behaviour with increasing salinity was also observed in estuarine samples from the Cape Fear River system, North Carolina, USA. In contrast, only minor changes were determined in molecular formulae for surface water samples collected along a transect off the Otago Coast and across the Subtropical Convergence (STC) into Subantarctic Water (SAW). However, a comparison of the molecular formulae assigned to the DOM pool for the STC water and a freshwater stream in Doubtful Sound, revealed that 75 % of all the assigned formulae for the open ocean sample were common to these two markedly different types of natural waters. This seemingly refractory DOM contained nearly 600 assigned molecular formulae, which were all very similar (only spaced by two hydrogen and CH₂ groups) and could be explained with only 9 general molecular formulae. However, the comparison of all assigned formulae for the freshwater sample suggested that about 90 % of the assigned molecular formulae for the terrestrially-derived DOM changed as it moved from rivers to the open ocean and that only 10 % remained the same. Singlet oxygen showed a very close relationship with the optical properties such as the absorption coefficients (a[CDOM](355)) and the EEM fluorescence intensities and these results suggested that singlet oxygen steady state concentrations are linked to CDOM. Photodegradation processes were confirmed to be responsible for a significant destruction of CDOM. Samples collected from different salinity waters showed major differences in wavelength-dependent photo-decay of CDOM suggesting that the rate of photodegradation in the UV range decreased with increase in salinity whereas it was enhanced for longer wavelength radiation ([greater than or equal to]400 nm). Additionally, the predominantly unsaturated compounds produced during estuarine mixing were found to be highly photolabile and were either destroyed or new unsaturated compounds were produced within 21 h of solar irradiation.
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Punt, Monique M. "Microwave-enhanced extraction of organic contaminants from soil." Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=27393.

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The Microwave-Assisted Process (MAP$ sp{ rm TM}$) is an enhanced extraction technology patented by Environment Canada. MAP uses microwaves to rapidly transfer target compounds from one phase to another by selectively heating the phase containing the target compounds. This thesis presents the results of research performed to determine whether the MAP technique can be further developed into a large-scale soil treatment process that overcomes the limitations of conventional remediation technologies.
The dielectric properties of several mixtures of acetone and hexane over a temperature range from 25$ sp circ$C to 50$ sp circ$C were measured. The dielectric constants of these mixtures were found not to vary significantly with temperature.
A study of microwave absorption by heterogeneous mixtures showed that adding a solid material to a low dielectric constant solvent resulted in energy being preferentially absorbed by the solid.
The results of laboratory extraction tests showed that the ability of the MAP technique to extract contaminants was affected by the organic matter content of soil, particularly in the presence of water.
Use of a closed-vessel system yielded a 60% to 175% increase in the extraction of PAHs from a low organic-content soil relative to that achieved in an open-vessel system. (Abstract shortened by UMI.)
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Lui, Yuen Shan. "Formation of disinfection by-products and mutagenicity upon chlorination of algal-derived organic materials." HKBU Institutional Repository, 2010. http://repository.hkbu.edu.hk/etd_ra/1181.

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Floge, Sheri Ann. "Seasonal Variations in Colloidal Chromophoric Dissolved Organic Matter (CDOM) in the Damariscotta River Estuary, Maine." Fogler Library, University of Maine, 2005. http://www.library.umaine.edu/theses/pdf/FlogeSA2005.pdf.

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Kothawala, Dolly N. "Controls on the soil solution partitioning of dissolved organic carbon and nitrogen in the mineral horizons of forested soils." Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=115565.

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The soil-solution partitioning of dissolved organic carbon (DOC) withinmineral soil horizons is primarily controlled by processes of adsorption and desorption. These abiotic processes largely occur within a short equilibration time of seconds to minutes, which generally occur faster than microbial processes. To characterise the adsorption of DOC to mineral soils, I used the Langmuir adsorption isotherm, which holds several advantages to the commonly used linear initial mass (IM) isotherm. One advantage to using the Langmuir isotherm is anestimation of the maximum DOC adsorption capacity (Qmax). The Qmax estimates the number of remaining DOC binding sites available on the mineral soil particle surfaces. I modified the traditional Langmuir isotherm in order to estimate the DOC desorption potential of native soil organic matter (SOC).[...]
Le partitionnement entre les solutions de sols du carbone organiquedissous (COD) dans les horizons des sols minéraux est essentiellement contrôle par les processus d'adsorption et de désorption. Ces processus abiotiques se déroulent normalement dans un bref temps d'équilibration variant de quelques secondes a quelques minutes, ce qui est en général plus rapide que les processus microbiens. Pour caractériser Fadsorption de COD aux sols minéraux, nous avons utilise l'isotherme d'adsorption de Langmuir. Cette isotherme présente plusieurs avantages par rapport a Fisotherme de masses initiales (IM) linéaires couramment utilisée, en particulier F estimation de la capacité d'adsorption maximale du COD (Qmax). Le Qmax estime le nombre de sites de liaison de COD restants a la surface du sol minéral. Nous avons aussi modifie Fisotherme de Langmuir traditionnelle afin d'évaluer le potentiel de désorption de COD de la matière organique du sol indigène (MOS).[...]
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Kothawala, Dolly N. 1972. "Controls on the soil solution partitioning of dissolved organic carbon and nitrogen in the mineral horizons of forested soils." Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=115858.

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The soil-solution partitioning of dissolved organic carbon (DOC) within mineral soil horizons is primarily controlled by processes of adsorption and desorption. These abiotic processes largely occur within a short equilibration time of seconds to minutes, which generally occur faster than microbial processes. To characterise the adsorption of DOC to mineral soils, I used the Langmuir adsorption isotherm, which holds several advantages to the commonly used linear initial mass (IM) isotherm. One advantage to using the Langmuir isotherm is an estimation of the maximum DOC adsorption capacity (Qmax). The Qmax estimates the number of remaining DOC binding sites available on the mineral soil particle surfaces. I modified the traditional Langmuir isotherm in order to estimate the DOC desorption potential of native soil organic matter (SOC).
Sorption characteristics were derived for a broad range of52 mineral soils collected from 17 soil profiles spanning across Canada from British Columbia to Quebec. Mineral horizons with the greatest Qmax included the Fe-enriched B horizons of acidic Podzols and Volcanic soils, followed by B horizons not enriched in Fe, followed by A and C horizons. Podzol B horizons were distinct from all other horizons due to significantly higher desorption potential. Soil properties predicting the adsorption characteristics of DOC also predicted the adsorption characteristics of dissolved organic nitrogen (DON). Adsorption of DOC and DON was tightly coupled (R 2 = 0.86), however the ratio of DOC:DON in the final equilibrium solution lowered for 48 out of 52 minerals horizons. These results suggest that DON may be slightly more mobile than DOC.
A short-term (32 day) incubation was perform to establish the fate of indigenous soil C, relative to newly adsorbed soil C to four mineral soils with different adsorption characteristics. Soil columns were leached periodically and sampled for DOC and CO2 production. Two Fe-enriched mineral horizons with high adsorption capacity released low amounts of old SOC, yet released almost all of the newly adsorbed SOC. In contrast, two B horizons without Fe-enrichment released greater amounts of old SOC, and retained a greater fraction of the newly adsorbed SOC than the Fe-enriched horizons. These results identify a contrast between the fate of indigenous and newly adsorbed SOC on mineral soils with differing Qmax.
The final component of this study examined changes to the molecular structure of DOC after equilibration with mineral soils. Multiple techniques were used to assess changes in the molecular composition of DOC, including the analysis of aromatic content by specific UV absorbance (SUVA) and fluorescence spectroscopy, analysis of molecular weight distribution (MWD) with high performance size exclusion chromatography (HPSEC) and functional group analysis with Fourier transform infra-red spectroscopy (FTIR). The solution phase DOC generally showed a reduced aromatic content, along with the removal of organic compounds with carboxyl groups. The MWD of DOC was reduced after equilibration to mineral soils, and the reduction in average molecular weight was related to the Qmax of mineral soils.
The various components of this thesis have contributed to the overall understanding of controls on the adsorption of DOC and DON species to mineral soils of the Canadian temperate and boreal forest.
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Sendel, Sebastian. "Wpływ lotnych związków organicznych wydzielanych przez pszenicę pod wpływem żerowania owadów oraz syntetycznego dihydrojasmonu na zachowanie dorosłych osobników lednicy zbożowej (Aelia acuminata L.)." Rozprawa doktorska, Uniwersytet Technologiczno-Przyrodniczy w Bydgoszczy, 2015. http://dlibra.utp.edu.pl/Content/789.

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Celem pracy jest określenie wpływu stresu powstałego w wyniku żerowania Aelia acuminata L. i działania syntetycznego dihydrojasmonu na wydzielanie LZO przez rośliny pszenicy jarej oraz określenie wpływu syntetycznych mieszanin LZO wydzielanych przez pszenicę na imagines A. acuminata L.
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Abraham, Muriel. "Spatial variation in soil organic carbon and stable carbon isotope signature in a pasture and a primary forest in central Panamá." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=80159.

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Soil properties and their spatial variability was measured to provide a strong database to assess the modification in soil properties associated with future changes in land use. Surface (0--10 cm) soil samples were collected from a 9 ha, 46-year-old pasture being converted to a native tree plantation and a neighboring control pasture near Sardinilla, Panama. A small-scale nested grid of surface soil samples was replicated in the future plantation and a primary forest in the region to evaluate the spatial variability of soil properties. Seven 1 m profiles were sampled in the future plantation and litter samples were collected at the forest and the future plantation.
Assuming the three sites were identical before the conversion to pasture, the difference in surface soil organic carbon (SOC) was 0.75 kg m-2 or equivalent to a loss of 0.017 kg m-2 yr -1 since the original land-use change. The control pasture is higher in bulk density but lower in percent SOC than the future plantation, which is critical to future comparisons.
The pasture soils showed signs of soil compaction and of the homogenization of soil properties. For the 7 profiles in the future plantation, total SOC mass ranged from 13.45 to 23.80 kg m-2, and stable isotopes revealed that 82% of the SOC in the top 10 cm is derived from the pasture vegetation, down to 23% at 1 m depth.
Spatially, the full scale of spatial variability was not determined from the nested grids alone. In addition, the 15 x 15 m grid in the future plantation generally over-estimated the semivariance at the scales below 3 m. The nested grids assessed the minimum measurable semivariance below 5 m.
The precision of surface estimations from point observations can be improved by adding a 5 x 5 m grid to any large-scale sampling scheme.
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Hong, Huachang. "Characteristics of natural organic matter in Hong Kong's source drinking water and its association with the formation of disinfection by-products." HKBU Institutional Repository, 2008. http://repository.hkbu.edu.hk/etd_ra/894.

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Books on the topic "Organic compound content"

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E, Lewis Timothy, United States. Environmental Protection Agency. Office of Research and Development, and United States. Environmental Protection Agency. Office of Solid Waste and Emergency Response, eds. Soil sampling and analysis for volatile organic compounds. [Washington, D.C.]: U.S. Environmental Protection Agency, Office of Research and Development, Office of Solid Waste and Emergency Response, 1991.

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Leventhal, Joel S. Soil organic carbon content in rice soils of Arkansas and Louisiana and a comparison to non-agricultural soils, including a bibliography for agricultural soil carbon. [Denver, CO]: U.S. Geological Survey, 1997.

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Leventhal, Joel S. Soil organic carbon content in rice soils of Arkansas and Louisiana and a comparison to non-agricultural soils, including a bibliography for agricultural soil carbon. [Denver, CO]: U.S. Geological Survey, 1997.

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Fu, Jaw-Kwei. Pollutant sorption to soils and sediments in organic/aqueous solvent systems. Athens, GA: U.S. Environmental Protection Agency, Environmental Research Laboratory, 1985.

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Fu, Jaw-Kwei. Pollutant sorption to soils and sediments in organic/aqueous solvent systems. Athens, GA: U.S. Environmental Protection Agency, Environmental Research Laboratory, 1985.

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G, Zepp Richard, and Sonntag Ch, eds. The role of nonliving organic matter in the earth's carbon cycle: Report of the Dahlem Workshop on the Role of Nonliving Organic Matter in the Earth's Carbon Cycle, Berlin 1993, September 12-17. Chichester: J. Wiley, 1995.

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Hydes, D. J. Determination of dissolved nutrients in seawater: With high precision and inter-comparability using gas-segmented continuous flow analysers. [Tokyo]: National Diet Library of Japan, 2012.

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Wetz, Jennifer Jarrell. Pump station data report for the May 2001, August 2001 and January 2003 COAST cruises: Nutrients, extracted chlorophyll, and dissolved and particulate organic carbon and nitrogen. Corvallis, Or: College of Oceanic and Atmospheric Sciences, Oregon State University, 2005.

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Bot, Alexandra. The importance of soil organic matter: Key to drought-resistant soil and sustained food production. Rome: Food and Agriculture Organization of the United Nations, 2005.

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Reilly, Timothy J. Dissolved pesticides, dissolved organic carbon, and water-quality characteristics in selected Idaho streams, April-December 2010. Reston, Va: U.S. Dept. of the Interior, U.S. Geological Survey, 2012.

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Book chapters on the topic "Organic compound content"

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He, Zhongqi, Daniel C. Olk, and Heidi M. Waldrip. "Soil Amino Compound and Carbohydrate Contents Influenced by Organic Amendments." In Applied Manure and Nutrient Chemistry for Sustainable Agriculture and Environment, 69–82. Dordrecht: Springer Netherlands, 2014. http://dx.doi.org/10.1007/978-94-017-8807-6_4.

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Raychaudhury, Chandan, and Debnath Pal. "Information Content Measures and Prediction of Physical Entropy of Organic Compounds." In Mathematical Foundations and Applications of Graph Entropy, 233–58. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2016. http://dx.doi.org/10.1002/9783527693245.ch8.

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Verona, A., A. P. Azhim, H. P. Liliek, D. U. Wahyu, and M. Ibrahim. "Utilization of Fly Ash and Bottom Ash as a Filler in the NPK Plant at Petrokima Gresik Ltd." In Proceedings of the 19th International Symposium on Management (INSYMA 2022), 1112–16. Dordrecht: Atlantis Press International BV, 2022. http://dx.doi.org/10.2991/978-94-6463-008-4_137.

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AbstractCoal is a rock composed of organic compounds (C, H, and O), inorganic or mineral impurities, and ash content. Burning coal produces waste in fly ash and bottom ash (FABA). FABA that accumulates for a long time can cause environmental problems, such as pollution. Petrokimia Gresik Ltd. Produces FABA in large quantities, so it must be managed by external parties who have a permit to manage it. With the regulatory changes, FABA can be utilized for various products. This study aims to utilize FABA as a filler substitute for raw materials for NPK fertilizer and find the right proportion so that utilization can be carried out optimally. This study applied the Plan-Do-Check-Act (PDAC) method to achieve continuous improvement. The results show that the most optimal FABA ratio is 3:1 with the addition of ZA raw materials with a specific ratio. After analyzing the test product on NPK 15-10-12 plus fertilizer, it is found that the NPK 15-10-12 plus fertilizer using FABA as a filler complies with SNI 2083:2012 about NPK fertilizer. The effectiveness test results on paddy plants at the Experimental Garden of Petrokimia Gresik Ltd. Show that FABA as a fertilizer filler does not affect the effectiveness of NPK fertilizer. This study shows that FABA can be used as a filler substitute for raw materials for NPK fertilizer.
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Rahmat, Somayeh, and Zhaleh Soheilikhah. "Arbuscular Mycorrhizal Fungi and Plant Secondary Metabolism." In Arbuscular Mycorrhizal Fungi and Higher Plants, 99–121. Singapore: Springer Nature Singapore, 2024. http://dx.doi.org/10.1007/978-981-99-8220-2_5.

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AbstractPlants synthetize and accumulate a various class of organic compounds known as secondary metabolites (SMs). Although SMs do not play a crucial role as primary metabolites in plant growth and development, they are of high ecological significance. Humans use these compounds in the pharmaceutical industry. One of the results of mutual symbiotic association between plants and arbuscular mycorrhizal fungi (AMF) is the reprogramming of metabolic pathways and modulating the range and content of plant SMs such as phenolics, terpenoids, and alkaloids. Many of SMs act as signals for multiple interactions between plants and AMF, from the pre-symbiotic stage to the creation/formation of a functional symbiosis. This chapter briefly reviews the current research status in the field of SM changes under the influence of AMF. The plant association with AMF increases the production and accumulation of SMs directly through improving water and nutrient uptake and enhancing the photosynthetic capacity or indirectly by provoking the biosynthetic pathways of SMs through generation of signaling molecules and changes in the concentration of phytohormones. The extent to which AMF affect plant SMs depends on the plant and fungus species and environmental factors.
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Krätschmer, Kerstin, Walter Vetter, Jiří Kalina, and Rainer Malisch. "WHO- and UNEP-Coordinated Human Milk Studies 2000–2019: Findings of Chlorinated Paraffins." In Persistent Organic Pollutants in Human Milk, 343–82. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-34087-1_10.

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AbstractChlorinated paraffins (CP) are complex mixtures of several million theoretically possible individual compounds. Contrary to medium-chain CP (MCCP, C14–C17) and long-chain CP (LCCP, C18–C30), the third sub-group investigated, short-chain chlorinated paraffins (SCCP, C10–C13), have been listed in 2017 in Annex A (Elimination) of the Stockholm Convention on Persistent Organic Pollutants. The concentrations of CP were determined in 84 nation-wide pooled human milk samples collected between 2009 and 2019 in 57 countries participating in exposure studies coordinated by the World Health Organization and the United Nations Environment Programme. Until 2015, only total CP content was determined. In light of on-going efforts to also add other CP groups to the Annexes of the Stockholm Convention and the glaring lack of data on the general background contamination worldwide, later analysis determined SCCP and MCCP and investigated the presence of LCCP (C18–C20 only). CP were present in all 84 samples, ranging 8.7–700 ng/g lipid. A statistically significant increase rate of total CP concentrations in human milk of 30% over 10 years was found on a global level, with a considerable variation between UN Regional Groups. Homologue group patterns indicated higher shares of MCCP and LCCP in industrialized countries and economically dependent areas. Compared to all other POPs analysed in the samples, the concentration of the sum of SCCP and MCCP was in most cases only surpassed by DDT, except European countries with high shares of PCB. Considering the ubiquitous presence of CP in humans worldwide, further investigation into toxicological effects and human exposure seems more pressing than ever, so that regulatory action may follow.
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Czernych, Radoslaw, Artur J. Badyda, Grazyna Gałęzowska, Lidia Wolska, and Pawel Zagożdżon. "Indoor Exposure to Volatile Organic Compounds in Children: Health Risk Assessment in the Context of Physiological Development." In Pulmonary Care and Clinical Medicine, 43–53. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/5584_2017_31.

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Malisch, Rainer, Alexander Schächtele, Ralf Lippold, Björn Hardebusch, Kerstin Krätschmer, F. X. Rolaf van Leeuwen, Gerald Moy, et al. "Overall Conclusions and Key Messages of the WHO/UNEP-Coordinated Human Milk Studies on Persistent Organic Pollutants." In Persistent Organic Pollutants in Human Milk, 615–75. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-34087-1_16.

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AbstractBuilding on the two rounds of exposure studies with human milk coordinated by the World Health Organization (WHO) in the mid-1980s and 1990s on polychlorinated biphenyls (PCB), polychlorinated dibenzo-p-dioxins (PCDD), and polychlorinated dibenzofurans (PCDF), five expanded studies on persistent organic pollutants (POPs) were performed between 2000 and 2019. After the adoption of the Stockholm Convention on POPs (the Convention) in 2001, WHO and the United Nations Environment Programme (UNEP) collaborated in joint studies starting in 2004. The collaboration aimed at provision of POPs data for human milk as a core matrix under the Global Monitoring Plan (GMP) to assess the effectiveness of the Convention as required under Article 16. Over time, the number of analytes in the studies expanded from the initial 12 POPs targeted by the Convention for elimination or reduction to the 30 POPs covered under the Stockholm Convention and two other POPs proposed for listing as of 2019. Many of these chemicals have numerous congeners, homologous groups, isomeric forms, and transformation products, which significantly extends the number of recommended analytes.In the studies between 2000 and 2019, 82 countries from all five United Nations regions participated, of which 50 countries participated in more than one study. For the human milk samples of the 2016–2019 period, results are available for the full set of 32 POPs of interest for the Convention until 2019: (i) the 26 POPs listed by the start of the study in 2016; (ii) decabromodiphenyl ether [BDE-209] and short-chain chlorinated paraffins [SCCP] as listed in 2017; (3) dicofol and perfluorooctanoic acid [PFOA] as listed in 2019; (4) medium-chain chlorinated paraffins [MCCP] and perfluorohexane sulfonic acid [PFHxS] as proposed for listing. This is a unique characteristic among the core matrices under the GMP.Four key messages can be derived: These studies are an efficient and effective tool with global coverage as key contributor to the GMP. After collection of a large number of individual samples (usually 50) fulfilling protocol criteria, pooled samples are prepared using equal aliquots of individual samples (physical averaging) and are considered to be representative for a country, subregion or subpopulation at the time of the sampling. The analysis of pooled representative human milk samples by dedicated Reference Laboratories meeting rigorous quality criteria contributes to reliability and comparability and reduces uncertainty of the analytical results. Additionally, this concept is very cost-effective. These studies can be used for regional differentiation based on concentrations of individual POPs between and within the five UN Regional Groups (African Group, Asia-Pacific Group, Eastern European Group, Group of Latin American and Caribbean Countries; Western European and Others Group). For some POPs, a wide range of concentrations with up to three orders of magnitude between lower and upper concentrations was found, even for countries in the same UN region. Some countries had levels within the usual range for most POPs, but high concentrations for certain POPs. Findings of concentrations in the upper third of the frequency distribution may motivate targeted follow-up studies rather than if the observed level of a POP is found in the lower third of frequency distribution. However, the concentration of a POP has also to be seen in context of the sampling period and the history and pattern of use of the POPs in each country. Therefore, results are not intended for ranking of individual countries but rather to distinguish broader patterns. These studies can provide an assessment of time trends, as possible sources of variation were minimized by the survey concepts building on two factors (sampling design; analysis of the pooled samples by dedicated Reference Laboratories). The estimation of time trends based on comparison of median or mean concentrations in UN Regional Groups over the five surveys in five equal four-year periods between 2000 and 2019 provides a first orientation. However, the variation of the number of countries participating in a UN Regional Group in a certain period can influence the median or mean concentrations. Thus, it is more prudent to only use results of countries with repeated participation in these studies for drawing conclusions on temporal trends. The reduction rates in countries should be seen in context with the concentration range: A differentiation of high levels and those in the range of the background contamination is meaningful. If high levels are found, sources might be detected which could be eliminated. This can lead to significant decrease rates over the following years. However, if low background levels are reported, no specific sources can be detected. Other factors for exposure, e.g. the contamination of feed and food by air via long-range transport and subsequent bioaccumulation, cannot be influenced locally. However, only very few time points from most individual countries for most POPs of interest are available, which prevents the derivation of statistically significant temporal trends in these cases. Yet, the existing data can indicate decreasing or increasing tendencies in POP concentrations in these countries. Furthermore, pooling of data in regions allows to derive statistically significant time trends in the UN Regional Groups and globally. Global overall time trends using the data from countries with repeated participation were calculated by the Theil–Sen method. Regarding the median levels of the five UN Regional Groups, a decrease per 10 years by 58% was found for DDT, by 84% for beta-HCH, by 57% for HCB, by 32% for PBDE, by 48% for PFOS, by 70% for PCB, and by 48% for PCDD and PCDF (expressed as toxic equivalents). In contrast, the concentrations of chlorinated paraffins (CP) as “emerging POPs” showed increasing tendencies in some UN Regional Groups. On a global level, a statistically significant increase of total CP (total CP content including SCCP [listed in the Convention in 2017] and MCCP [proposed to be listed]) concentrations in human milk of 30% over 10 years was found. The studies can provide the basis for discussion of the relative importance (“ranking”) of the quantitative occurrence of POPs. This, however, requires a differentiation between two subgroups of lipophilic substances ([i] dioxin-like compounds, to be determined in the pg/g [=ng/kg] range, and [ii] non-dioxin-like chlorinated and brominated POPs, to be determined in the ng/g [=μg/kg] range; both groups reported on lipid base) and the more polar perfluorinated alkyl substances (PFAS); reported on product base [as pg/g fresh weight] or on volume base [ng/L]. For this purpose, results for the complete set of the 32 POPs of interest for the 2016–2019 period were considered. By far, the highest concentrations of lipophilic substances were found for DDT (expressed as “DDT complex”: sum of all detected analytes, calculated as DDT; maximum: 7100 ng/g lipid; median: 125 ng/g lipid) and for chlorinated paraffins (total CP content; maximum: 700 total CP/g lipid; median: 116 ng total CP/g lipid). PCB was next in the ranking and had on average an order of magnitude lower concentrations than the average of the total CP concentrations. The high CP concentrations were caused predominantly by MCCP. If the pooled samples from mothers without any known major contamination source nearby showed a high level of CP, some individual samples (e.g. from local population close to emission sources, as a result of exposure to consumer products or from the domestic environment) might even have significantly higher levels. The lactational intake of SCCP and MCCP of the breastfed infant in the microgram scale resulting from the mothers’ dietary and environmental background exposure should therefore motivate targeted follow-up studies and further measures to reduce exposure (including in the case of MCCP, regulatory efforts, e.g. restriction in products). Further, due to observed levels, targeted research should look at the balance among potential adverse effects against positive health aspects for the breastfed infants for three groups of POPs (dioxin-like compounds; non-dioxin-like chlorinated and brominated POPs; PFAS) regarding potentially needed updates of the WHO guidance. As an overall conclusion, the seven rounds of WHO/UNEP human milk exposure studies are the largest global survey on human tissues with a harmonized protocol spanning over the longest time period and carried out in a uniform format. Thus, these rounds are an effective tool to obtain reliable and comparable data sets on this core matrix and a key contributor to the GMP. A comprehensive set of global data covering all POPs targeted by the Stockholm Convention, in all UN Regional Groups, and timelines covering a span of up to three decades allows to evaluate data from various perspectives. A widened three-dimensional view is necessary to discuss results and can be performed using the three pillars for assessments of the comprehensive data set, namely: analytes of interest; regional aspects; time trends. This can identify possible problems for future targeted studies and interventions at the country, regional, or global level. Long-term trends give an indication of the effectiveness of measures to eliminate or reduce specific POPs. The consideration of countries with repeated participation in these studies provides the best possible database for the evaluation of temporal trends. The continuation of these exposure studies is important for securing sufficient data for reliable time trend assessments in the future. Therefore, it is highly recommended to continue this monitoring effort, particularly for POPs that are of public health concern.
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Ntinyari, Winnie, and Joseph P. Gweyi-Onyango. "Greenhouse Gases Emissions in Agricultural Systems and Climate Change Effects in Sub- Saharan Africa." In African Handbook of Climate Change Adaptation, 1081–105. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-45106-6_43.

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AbstractClimate change has been viewed to result from anthropogenic human activities that have significantly altered the Nitrogen (N) cycle and carbon cycles, increasing the risks of global warming and pollution. A key cause of global warming is the increase in greenhouse gas emissions including methane, nitrous oxide, and carbon among others. The context of this chapter is based on a comprehensive desktop review on published scientific papers on climate change, greenhouse emissions, agricultural fertilizer use, modeling and projections of greenhouse gases emissions. Interestingly, sub-Saharan Africa (SSA) has the least emissions of the greenhouses gases accounting for only 7% of the total world’s emissions, implying that there is overall very little contribution yet it has the highest regional burden concerning climate change impacts. However, the values could be extremely higher than this due to lack of proper estimation and measurement tools in the region and therefore, caution needs to be taken early enough to avoid taking the trend currently experienced in developed nations. In SSA, agricultural production is the leading sector in emissions of N compound to the atmosphere followed by energy and transportation. The greatest challenge lies in the management of the two systems to ensure sufficiency in food production using more bioenergy hence less pollution. Integrating livestock and cropping systems is one strategy that can reduce methane emissions. Additionally, developing fertilizer use policy to improve management of fertilizer and organic manure have been potentially considered as effective in reducing the effects of agriculture activities on climate change and hence the main focus of the current chapter.
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Germain, Aurèle, Marta Corno, and Piero Ugliengo. "Computing Binding Energies of Interstellar Molecules by Semiempirical Quantum Methods: Comparison Between DFT and GFN2 on Crystalline Ice." In Computational Science and Its Applications – ICCSA 2021, 632–45. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-86976-2_43.

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AbstractInterstellar Grains (IGs) spread in the Interstellar Medium (ISM) host a multitude of chemical reactions that could lead to the production of interstellar Complex Organic Molecules (iCOMs), relevant in the context of prebiotic chemistry. These IGs are composed of a silicate-based core covered by several layers of amorphous water ice, known as a grain mantle. Molecules from the ISM gas-phase can be adsorbed at the grain surfaces, diffuse and react to give iCOMs and ultimately desorbed back to the gas phase. Thus, the study of the Binding Energy (BE) of these molecules at the water ice grain surface is important to understand the molecular composition of the ISM and its evolution in time. In this paper, we propose to use a recently developed semiempirical quantum approach, named GFN-xTB, and more precisely the GFN2 method, to compute the BE of several molecular species at the crystalline water ice slab model. This method is very cheap in term of computing power and time and was already showed in a previous work to be very accurate with small water clusters. To support our proposition, we decided to use, as a benchmark, the recent work published by some of us in which a crystalline model of proton-ordered water ice (P-ice) was adopted to predict the BEs of 21 molecules relevant in the ISM. The relatively good results obtained confirm GFN2 as the method of choice to model adsorption processes occurring at the icy grains in the ISM. The only notable exception was for the CO molecule, in which both structure and BE are badly predicted by GFN2, a real pity due to the relevance of CO in astrochemistry.
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Werheni Ammeri, Rim, Yassine Hidri, and Hassen Abdenaceur. "Effect of PCP Pesticide Contamination on Soil Quality." In Soil Contamination - Threats and Sustainable Solutions. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.93714.

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In recent years, soil contamination with pesticides has become a crucial news issue with serious short- and long-term effects on human health and its environment. Pesticides play a significant role in the success of modern farming and food production. These compounds have potential for toxicity and adverse effects on human health and ecological soil systems. Pentachlorophenol (PCP) is one of the most recalcitrant chemicals polluting the environment for its stable aromatic ring system and chloride content. Nowadays, many sites are contaminated with this substance. In these areas, concentrations may stay high for a long time because of slow degradation in the soil due to the negative effects that PCP has on soil microbial populations. Bioremediation of PCP contaminated sites can be realized introducing directly, into a contaminated system, microorganisms able to consume selectively the target compound (bioaugmentation) or increasing the microbial indigenous population by addiction of nutrients in form of organic and/or inorganic fertilizers and biosolids (biostimulation). In the present chapter, we present an overview of the effect of PCP pesticide contamination on soil microbial populations (density and diversity), enzymatic activity and physicochemical parameters. Additionally, the bioremediation process will be detailed.
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Conference papers on the topic "Organic compound content"

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Campos, R. A., I. Kovalev, N. Wakili, Y. Guo, and T. Skotheim. "Electroluminescence from Organometallic Thin Films." In Organic Thin Films for Photonic Applications. Washington, D.C.: Optica Publishing Group, 1995. http://dx.doi.org/10.1364/otfa.1995.tuc.3.

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Efficient electrical conversion into a wide range of optical wavelengths as well as low fabrication costs are some of the attractions of organic thin films which drive the use of these materials for flat-panel display applications [1]. Since the pioneering work of Tang and VanSlyke in 1987 [2], the organometallic material tris-(8-hydroxyquinoline)-aluminum (ALQ) has been the focus of intense research. This compound electroluminesces in the green region of the spectrum over a broad spectrum peaked near 520 nm. Although ALQ microcavity architectures can provide narrowband emissions at select wavelengths [3], the resulting brightnesses in the blue and red regions are limited by the decreasing spectral content in the tails of the ALQ emission spectrum.
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Kot, A., V. Radchikov, I. Seryakov, and V. Petrov. "Рубцовое пищеварение и продуктивность молодняка крупного рогатого скота при скармливании органического кобальта." In Scientific and practical conference with international participation: "Management of the genetic fund of animals – problems, solutions, outlooks". Scientific Practical Institute of Biotechnologies in Animal Husbandry and Veterinary Medicine, 2023. http://dx.doi.org/10.61562/mgfa2023.38.

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The effect of cobalt acetic acid on the indicators of cicatricial digestion and protein metabolism in bulls aged 3-6 months was studied. The replacement of cobalt sulphate with cobalt acetic acid in the compound feed did not have a significant effect on the processes of scar digestion. All indicators were within the limits of physiological norms. The animals of the experimental group showed a tendency to decrease the ammonia content in the scar fluid by 4.2%. The use of concentrates with the addition of organic cobalt compounds helps to increase the productivity of animals and the efficiency of feed use. The average daily increase in live weight in the animals of the experimental group increased by 2.7%-4.5%. The increase in productivity had a positive effect on the efficiency of the transformation of nutrients in the diet into products. Thus, feed costs for products decreased by 2.8%.
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El Sayed, Mohamed, Michel Khammo, Mohamed Al Amri, Mona Al Hebshi, Hisham Mousa, Mahmoud Elwan, and Mahmoud Koriesh. "Comprehensive Approach for Tracing Back Potential Sources of Organic Chloride in Crude Oil." In Gas & Oil Technology Showcase and Conference. SPE, 2023. http://dx.doi.org/10.2118/214188-ms.

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Abstract Organic Chloride is organic compound that have chlorine atoms as part of its chemical composition. Over the last four years, there has been continuous increase of number of research papers addressing the corrosion impact of organic chlorides in processes that includes high temperature like distillation towers. Where chlorine atoms start to detach and form free radicals in moisture wetting metal surfaces and result in severe corrosion of distillation towers. The Fact that led regulatory agencies to set a threshold number for maximum allowable content of organic chloride in crude beyond which crude is either not accepted or depreciated. That puts pressure on oil producers to maintain acceptable levels of organic chloride content. Companies working in Refineries are more familiar with organic chlorides than upstream operators are. Having the regulatory agencies pushing on setting limits on maximum allowable content of organic chlorides in crude. Now many operators are looking for a way to keep monitoring OC within limits and to define potential sources. Organic Chlorides rarely naturally exist in crude oil. That means there should be external source to contaminate crude such as chemicals used during the extensive operations in the oil field from drilling chemicals, stimulation, production, process, ETC. A leading example from Gulf of Suez, late 2021 a concern was raised on organic chlorides levels in crude of one of the prolific fields and the risk was to have negative impact on crude oil pricing. The risk would be dramatic on the large scale since all crude from different fields gather at the processing facilities then goes to same storage tank. An integrated Multidisciplinary in house task force team was formed to investigate the root causes for OC levels. The team reviewed MSDS of all chemicals consumed in all operations, qualified a Lab from Local Market for testing OC in crude Following ASTM D4929. Developed a comprehensive sampling and tracing strategy to be able to trace back to root causes. Over 5 Months of Monitoring, tracing and correlation between ongoing daily operations and OC levels. In addition to testing chemicals for OC. It was concluded that batches of organic solvent from one supplier are contaminated by OC. Contaminated Batches were quarantined and not used for daily operations. Another supplier was qualified for temporary supply of this type of solvent. As a result of the deep investigation a set of lessons learnt and recommended practices were generated and communicated with different disciplines for awareness and compliance to maintain OC levels manageable. Which in return saved operator company from the risk of depreciation of Crude oil price. Testing Chemicals with organic components are key for eliminating OC in crude and this should be done in Batch basis.
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Al-Shamary, Noora. "Assessment of Organic and Inorganic Pollutants along the Qatari Coast." In Qatar University Annual Research Forum & Exhibition. Qatar University Press, 2021. http://dx.doi.org/10.29117/quarfe.2021.0036.

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Qatar sits in the middle of the world’s most important hydrocarbon producing areas where significant regional refining activity and shipping traffic take place. In addition to significant local coastline, development prominently along the eastern coast, has taken place over recent decades. Protecting Qatar’s marine ecosystems from the adverse effects of environmental contaminants is a core component of the Environmental Development pillar within the National Vision 2030. However, a limited number of studies have investigated contaminant concentrations in the coastal environment of Qatar. The accumulation of contaminants in aquatic environments can affect coastal and marine ecosystems, and cause adverse effect on marine organisms and human health. This study aims to determine contamination in Qatar’s coastal environment by measuring organic and inorganic contaminants, along with physiochemical parameters, at four sites located on the contrasting east and west coast of the country. The Pearl Oyster Pinctada radiata, which is considered an iconic organism in Qatar, was used to determine a baseline of contaminants in an aquatic organism. Surface seawater, surface sediment and oysters were collected four times over two years in different seasons from the four sites. In-situ parameters (temperature, pH, and salinity), and abiotic parameters (TOC and grain sizes) were measured for seawater and sediment. Organic (TPHs, PAHs) and inorganic contaminants (trace metals including: Cd, Cu, Cr, Ni, Pb and Zn, T-Hg) were measured in all samples. Overall, Al Wakra (higher in boat traffic and fueling activities) on the east coast reported the highest levels of contaminants. High PAHs were observed in oyster tissues, while high Pb was noted in seawater and high Zn was observed in sediment and oyster. Benzo (a) pyrene was the highest compound detected in oyster. However, high TPHs were also noted in oyster tissues from Simaisma. At Al Khor, also on the east coast, high level of TPHs were recorded in seawater, while high PAHs and TOC observed in surface sediment, which had a relatively higher clay and silt content than other sites. Umm Bab (with a desalination plant near the coast), the sole sample site on the west coast, showed the highest level of TOC in seawater and sediment, highest Ni in seawater and highest total mercury in oyster. Our results, in general, report lower levels in seawater and sediment compared to other studies in the region and more widely; however, in oysters most of the contaminants are higher when compared to international guideline values. These higher levels indicate the potential for these filter-feeding organisms to absorb contaminants into their tissues from the environment that surrounds them. Additionally, bioaccumulation can occur. This study provides background information for further investigation to understand the presence and distribution of organic and inorganic contaminants in Qatar’s rapidly changing coastal environment. It indicates the usefulness of applying a holistic view to environmental monitoring including the use of biomonitoring.
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Wu, Hongjun, Kun Huang, Ju Liu, Bao Zhang, Jiquan Liu, Change Kong, Jianxin Shen, et al. "Research and Application of Compound Plugging Removal Technology in HTHP Condensate Gas Well." In International Petroleum Technology Conference. IPTC, 2021. http://dx.doi.org/10.2523/iptc-21787-ms.

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Abstract Dabei and Dina 2 gas fields located in Tarim Oilfield are HTHP and high production condensate gas fields. The formation temperature is 136°C, the formation pressure is 105MPa, the gas production of single well is 40×104m3/d~100×104m3/d, and the condensate production is 35t/d~86t/d. After the HTHP condensate gas well started production, the oil production pressure continues to fluctuate and decline due to the wellbore plugging. By 2019, more than 80% of the HTHP condensate gas wells have the wellbore plugging problem, gas production of some wells reduced over 50%, a few wells even shut in, the normal production of condensate gas well is seriously affected. In some condensate gas wells of Dabei gas field, organic plugging substances are obtained in the wellhead and the nearby oil pipes during the well passing and other operations. Wax is detected and analyzed as the plugging substance. In addition, inorganic plugging substances are obtained at the bottom of the production pipe in the wells with serious plugging, through the coiled tubing dredging and overhaul operations, which are mainly concentrated at the reducing tool or screen pipe. The content of inorganic scale in the plug is 60% ~ 90%, and the rest is a small amount of formation sand. In view of the problem of wax deposition on the upper part of the wellbore and plugging the tubing of the condensate gas well, the condensate oil samples and wellbore wax samples were obtained on site. The experiment analysis confirmed that the condensate oil dewax temperature is 37.1°C, which can provide a reference for judging whether the wellbore had wax deposition. In order to solve the problem of wax deposition in the wellbore, the laboratory evaluation experiment of wax remover optimization was carried out to optimize the wax remover with good wax dissolving effect. In view of the inorganic scale plugging at the lower part of the wellbore, the research on the scaling mechanism of high-pressure well bore was clarified, and the high dissolution and low corrosion solution acid system was optimized through the laboratory experiment. For the wells with wax deposition and scale compound blockage, but have flow channel, a compound plugging removal technology is formed, which is to inject wax remover to remove the wax plug in the upper part of the well, and then inject acid system to remove the scale plug in the lower part of the well. For the wells with serious well plugging, a compound plugging removal technology is formed, which is to dredge the well through coiled tubing to form a flow channel, and then inject acid solution to remove the scale plug in the lower part of the well. Three wells have successfully implemented wax and scale compound plug removal, and the average single well productivity after plug removal is 2.7 times of that before plug removal, At present, the production of DB2-A Well has been stable for 22 months after plug removal. three wells have successfully implemented "coiled tubing dredging + wellbore acid plugging removal" complex plug removal, and the production capacity has been successfully restored after operation, the average single well tubing pressure is 60.4MPa, and the total daily natural gas production is 178×104m3/d. HTHP condensate gas well wellbore compound plug removal technology can remove the organic and inorganic plugging in the wellbore to the high efficiency recovery of the well.
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Mohan, Regi P., and Adarsh P. "Strength Characterisation of Nanochemical Stabilized Kuttanad Clay for Pavement Construction." In International Web Conference in Civil Engineering for a Sustainable Planet. AIJR Publisher, 2021. http://dx.doi.org/10.21467/proceedings.112.17.

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Kuttanad clays are low strength, soft, organic clay deposits found in the Kuttanad areas of the Alappuzha district, Kerala. Lots of failures have been reported to the structures built over it due to its swelling - shrinking characteristics. To enhance the load-bearing capacity and decrease the settlement characteristics, the addition of appropriate stabilizing agents is considered the most efficient technique in soil stabilization applications. Soil stabilization techniques using traditional stabilizers in mass projects have become costly due to the increase in the cost of materials like cement, lime, fly ash, etc. Moreover, cement production also accounts for global warming due to the emission of carbon gas. Hence studies are going on regarding the effectiveness of using non-traditional materials that can react faster as stabilizing agents and thus reducing the cost of construction. This paper focuses on studying the suitability of a non-traditional nanotechnology-based organo-silane compound in the treatment of Kuttanad clay soils. Observations were made for the variation in the strength characteristics of the soil such as maximum dry density, optimum moisture content, Unconfined Compressive Strength (UCS), California Bearing Ratio (CBR) strength of samples stabilized with varying dosages of nanochemical for curing periods up to 28days.
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Sobolev, Roman, Yuliya Frolova, Varuzhan Sarkisyan, and Alla Kochetkova. "Study of the Oxidative Stability of Oleogels Structured with Beeswax Fractions." In 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/zbfu3245.

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Combining the beeswax fractions is an effective way of structuring edible oils. However, their effect on oleogel oxidative stability is still not studied. Thus, the study on the influence of beeswax and combinations of its fractions on the edible oleogels oxidation was the objective of this research.Four fractions of beeswax (A, B, C, D) were isolated using preparative flash-chromatography and characterized by TLC and HPLC-ELSD. Sunflower oil was used to prepare oleogels (at 90 °C for 30 minutes) with a 6% of gelator. The fatty acid composition was evaluated by GC. The samples were stored at 35°C for 20 days, monitoring the oxidation using: PV, AV, CDV, TOTOX, HS-SPME-GC-MS. The induction period was determined using the OXITEST reactor.We have shown that fraction A contained hydrocarbons ( >99%); B - monoesters ( >95%); C - wax esters ( >66%), alcohols ( >29%), and free fatty acids ( >4%); D - alcohols ( >49%), free fatty acids ( >40%) and wax esters ( >10%). Combinations of A+B, A+B+C, and A+B+D gelators were made using fractions in equal amounts. The fatty acid composition of freshly prepared oleogels and oil didn't differ (p >0.05). Sunflower oil had the best oxidative stability among all samples. The A+B-based oleogel had the highest oxidative stability among the oleogels. Hexanal is shown to be the main volatile organic compound formed during the oxidation of sunflower oil. The volatile compounds profile of the oleogels also included ketones, alcohols, and terpenes. Beeswax-based oleogel had the lowest induction period, which indicates the presence of prooxidant components. A close correlation was found between the oxidation rate of oleogels and the content of free fatty acids (r2=0.8195) in the gelator.This study shows that the use of beeswax fractions, compared to beeswax itself, results in fat-containing products with higher oxidation stability.
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Tazuhara, Shion, Tomoya Aiba, Takashi Nagase, Takashi Kobayashi, Yuichi Sadamitsu, and Hiroyoshi Naito. "Influence of contact resistances on high-mobility top-gate organic transistors based on didodecylbenzothienobenzothiophene." In 2019 Compound Semiconductor Week (CSW). IEEE, 2019. http://dx.doi.org/10.1109/iciprm.2019.8819084.

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Alhabib, Hussain F., and Hani A. Nass. "Gas Treatment Produced Water Reuse." In SPE Water Lifecycle Management Conference and Exhibition. SPE, 2024. http://dx.doi.org/10.2118/219042-ms.

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Abstract Industrial produced wastewater management has been a challenging objective in the Oil and Gas Industry, and the adoption of systems to reuse it is essential to promote the circular economy principles. Saudi Aramco, adapted an integrated system to collect, treat, and reuse the facility-wide produced water to eliminate directing it to evaporation ponds, or outside the facility to waste management entities. Produced water, in gas plants, is usually formed in three processes: separating wells’ sour water from monoethyl-glycol, knocking out sour water during gas sweetening, and during acid gas handling and cooling. The produced water is instantly directed to sour water treatment to remove the hydrogen sulfide, and finally to a biological wastewater treatment plant. The wastewater treatment plant's objective is to reducing the total organic compound (TOC) content in the water through bacterial activity, and filtration. Once the TOC is minimized to the process requirement, it is reused within the plant as a cooling tower make-up water. It is both an environmental and an economical driven adoption. Produced wastewater is reused to reduce plant's purchased water quantity significantly, and it ultimately leads to minimize the facility's purchased fresh water quantity especially during the summer season where the evaporation rate is high. Also, this leads to a reduction of CO2 footprint as a result of avoided purchased water desalination (scope 2 carbon emission). This initiative also supports the circular economy principles by conserving the plant's water, and minimizing the demand on fresh products.
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Vakhin, Alexey V., Irek I. Mukhamatdinov, Firdavs A. Aliev, Dmitriy F. Feoktistov, Sergey A. Sitnov, Marat R. Gafurov, Ilgiz F. Minkhanov, et al. "Industrial Application of Nickel Tallate Catalyst During Cyclic Steam Stimulation in Boca De Jaruco Reservoir." In SPE Russian Petroleum Technology Conference. SPE, 2021. http://dx.doi.org/10.2118/206419-ms.

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Abstract A nickel-based catalyst precursor has been synthesized for in-situ upgrading of heavy crude oil that is capable of increasing the efficiency of steam stimulation techniques. The precursor activation occurs due to the decomposition of nickel tallate under hydrothermal conditions. The aim of this study is to analyze the efficiency of in-situ catalytic upgrading of heavy oil from laboratory scale experiments to the field-scale implementation in Boca de Jaruco reservoir. The proposed catalytic composition for in-reservoir chemical transformation of heavy oil and natural bitumen is composed of oil-soluble nickel compound and organic hydrogen donor solvent. The nickel-based catalytic composition in laboratory-scale hydrothermal conditions at 300°С and 90 bars demonstrated a high performance; the content of asphaltenes was reduced from 22% to 7 wt.%. The viscosity of crude oil was also reduced by three times. The technology for industrial-scale production of catalyst precursor was designed and the first pilot batch with a mass of 12 ton was achieved. A «Cyclic steam stimulation» technology was modified in order to deliver the catalytic composition to the pay zones of Boca de Jaruco reservoir (Cuba). The active forms of catalyst precursors are nanodispersed mixed oxides and sulfides of nickel. The pilot test of catalyst injection was carried out in bituminous carbonate formation M, in Boca de Jaruco reservoir (Cuba). The application of catalytic composition provided increase in cumulative oil production and incremental oil recovery in contrast to the previous cycle (without catalyst) is 170% up to date (the effect is in progress). After injection of catalysts, more than 200 samples from production well were analyzed in laboratory. Based on the physical and chemical properties of investigated samples and considering the excellent oil recovery coefficient it is decided to expand the industrial application of catalysts in the given reservoir. The project is scheduled on the fourth quarter of 2021.
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Reports on the topic "Organic compound content"

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Akinleye, Taiwo, Idil Deniz Akin, Amanda Hohner, Indranil Chowdhury, Richards Watts, Xianming Shi, Brendan Dutmer, James Mueller, and Will Moody. Evaluation of Electrochemical Treatment for Removal of Arsenic and Manganese from Field Soil. Illinois Center for Transportation, June 2021. http://dx.doi.org/10.36501/0197-9191/21-019.

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Soils containing inorganic compounds are frequently encountered by transportation agencies during construction within the right-of-way, and they pose a threat to human health and the environment. As a result, construction activities may experience project delays and increased costs associated with management of inorganic compounds containing soils required to meet environmental regulations. Recalcitrance of metal-contaminated soils toward conventional treatment technologies is exacerbated in clay or organic content-rich fine-grained soils with low permeability and high sorption capacity because of increased treatment complexity, cost, and duration. The objective of this study was to develop an accelerated in situ electrochemical treatment approach to extract inorganic compounds from fine-grained soils, with the treatment time comparable to excavation and off-site disposal. Three reactor experiments were conducted on samples collected from two borehole locations from a field site in Illinois that contained arsenic (As)(~7.4 mg/kg) and manganese (Mn)(~700 mg/kg). A combination of hydrogen peroxide (H2O2) and/or citrate buffer solution was used to treat the soils. A low-intensity electrical field was applied to soil samples using a bench-scale reactor that resembles field-scale in situ electrochemical systems. For the treatment using 10% H2O2 and citrate buffer solution, average removal of 23% and 8% were achieved for Mn and As, respectively. With 4% H2O2 and citrate buffer, 39% and 24% removal were achieved for Mn and As; while using only citrate buffer as the electrolyte, 49% and 9% removal were achieved for Mn and As, respectively. All chemical regimes adopted in this study reduced the inorganic compound concentrations to below the maximum allowable concentration for Illinois as specified by the Illinois Environmental Protection Agency. The results from this work indicate that electrochemical systems that leverage low concentrations of hydrogen peroxide and citrate buffer can be effective for remediating soils containing manganese and arsenic.
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Chefetz, Benny, and Baoshan Xing. Sorption of hydrophobic pesticides to aliphatic components of soil organic matter. United States Department of Agriculture, 2003. http://dx.doi.org/10.32747/2003.7587241.bard.

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Sorption of hydrophobic compounds to aliphatic components of soil organic matter (SOM) is poorly understood even though these aliphatic carbons are a major fraction of SOM. The main source of aliphatic compounds in SOM is above- and below-ground plant cuticular materials (cutin, cutan and suberin). As decomposition proceeds, these aliphatic moieties tend to accumulate in soils. Therefore, if we consider that cuticular material contributes significantly to SOM, we can hypothesize that the cuticular materials play an important role in the sorption processes of hydrophobic compounds (including pesticides) in soils, which has not yet been studied. The overall goal of this research was to illustrate the mechanism and significance of the refractory aliphatic structures of SOM in sorbing hydrophobic compounds (nonionic and weakly polar pesticides). The importance of this study is related to our ability to demonstrate the sorption relationship between key pesticides and an important fraction of SOM. The specific objectives of the project were: (1) To isolate and characterize cuticular fractions from selected plants; (2) To investigate the sorption mechanism of key hydrophobic pesticides and model compounds to cuticular plant materials; (3) To examine the sorption mechanisms at the molecular level using spectroscopic techniques; (4) To investigate the sorption of key hydrophobic pesticides to synthetic polymers; (5) To evaluate the content of cuticular materials in agricultural soils; and (6) To study the effect of incubation of plant cuticular materials in soils on their sorptive capabilities. This project demonstrates the markedly high sorption capacity of various plant cuticular fractions for hydrophobic organic compounds (HOCs) and polar organic pollutants. Both cutin (the main polymer of the cuticle) and cutan biopolymers exhibit high sorption capability even though both sorbents are highly aliphatic in nature. Sorption by plant cuticular matter occurs via hydrophobic interactions and H-bonding interactions with polar sorbates. The cutin biopolymer seems to facilitate reversible and noncompetitive sorption, probably due to its rubbery nature. On the other hand, the epicuticular waxes facilitate enhance desorption in a bi-solute system. These processes are possibly related to phase transition (melting) of the waxes that occur in the presence of high solute loading. Moreover, our data highlight the significance of polarity and accessibility of organic matter in the uptake of nonpolar and polar organic pollutants by regulating the compatibility of sorbate to sorbent. In summary, our data collected in the BARD project suggest that both cutin and cutan play important roles in the sorption of HOCs in soils; however, with decomposition the more condensed structure of the cutin and mainly the cutan biopolymer dominated sorption to the cuticle residues. Since cutin and cutan have been identified as part of SOM and humic substances, it is suggested that retention of HOCs in soils is also controlled by these aliphatic domains and not only by the aromaticrich fractions of SOM.
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Jung, Carina, Karl Indest, Matthew Carr, Richard Lance, Lyndsay Carrigee, and Kayla Clark. Properties and detectability of rogue synthetic biology (SynBio) products in complex matrices. Engineer Research and Development Center (U.S.), September 2022. http://dx.doi.org/10.21079/11681/45345.

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Synthetic biology (SynBio) aims to rationally engineer or modify traits of an organism or integrate the behaviors of multiple organisms into a singular functional organism through advanced genetic engineering techniques. One objective of this research was to determine the environmental persistence of engineered DNA in the environment. To accomplish this goal, the environmental persistence of legacy engineered DNA building blocks were targeted that laid the foundation for SynBio product development and application giving rise to “post-use products.” These building blocks include genetic constructs such as cloning and expression vectors, promoter/terminator elements, selectable markers, reporter genes, and multi-cloning sites. Shotgun sequencing of total DNA from water samples of pristine sites was performed and resultant sequence data mined for frequency of legacy recombinant DNA signatures. Another objective was to understand the fate of a standardized contemporary synthetic genetic construct (SC) in the context of various chassis systems/genetic configurations representing different degrees of “genetic bioavailability” to the environmental landscape. These studies were carried out using microcosms representing different environmental matrices (soils, waters, wastewater treatment plant (WWTP) liquor) and employed a novel genetic reporter system based on volatile organic compounds (VOC) detection to assess proliferation and persistence of the SC in the matrix over time.
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Ardakani, O. H. Organic petrography and thermal maturity of the Paskapoo Formation in the Fox Creek area, west-central Alberta. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/330296.

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The Paskapoo Formation, which ranges in age from middle to upper Paleocene, is the major shallow aquifer in Alberta. This study is part of a larger GSC-led study on the potential environmental impact of hydrocarbon development in the Fox Creek area (west-central Alberta) on shallow aquifers. Fox Creek is located near the northern limit of the Paskapoo Formation. In addition to the underlying organic-rich source rocks in the study area, including the Duvernay Formation that is currently exploited for hydrocarbon resources, the Paskapoo Formation contains organic-rich intervals and coal seams. In order to investigate any potential internal hydrocarbon sources within the Paskapoo Formation, ninety-seven (97) cutting samples from the formation obtained from eight shallow monitoring wells (50-90 m) in the study area were studied for total organic carbon (TOC) content, organic matter composition and thermal maturity of coal seams using programmed pyrolysis analysis and organic petrography. The TOC content of all samples ranges from 0.2 to 8.8 wt. %, with a mean value of 0.95 ± 1.6 wt. % (n=97). The Tmax values of studied samples range from 347 to 463 °C, with a mean value of 434 ± 20 °C that suggest a range of thermal maturity from immature to peak oil window. The random reflectance (Rr) measurement and fluorescence microscopy on eighteen (18) selected samples with TOC content > ~1 wt. % shows a mean Rr value of 0.27% and 0.42% for the overlying till deposits and the underlying shallow depth sandstone, siltstone, shale and coal seams respectively, indicating a low rank coal ranging from lignite to sub-bituminous coal. Blue to green and yellow fluorescing liptinite macerals further confirmed the low maturity of studied samples. The low S2 yield of a large part of the samples (65%) resulted in unreliable Tmax values that overestimated the thermal maturity. Although the organic matter in the studied intervals are immature, exsudatinite, as secondary liptinite maceral, was observed in samples from the lower parts of the studied monitoring wells. Exsudatinite generally derives from the transformation of sporinite, alginite, resinite and varieties of vitrinite, which is a resinous or asphalt like material. Considering the thickness and distribution of coal seams in the studied samples, it is unlikely the exsudatinite will be a major source for aquifer hydrocarbon contamination in the study area. Additional stratigraphic studies and molecular geochemical analysis could provide an estimate of the total volume of possible organic compounds contribution to the aquifer in the study area. Due to the presence of coal seams in the studied intervals of the Paskapoo Formation, it is important to investigate the possibility of biogenic methane formation in Paskapoo shallow aquifers.
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Silva, M. Preliminary investigation into the explosion potential of volatile organic compounds in WIPP (Waste Isolation Pilot Plant) CH-TRU (contact-handled--transuranic) waste. Office of Scientific and Technical Information (OSTI), June 1990. http://dx.doi.org/10.2172/6731209.

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Lifschitz, Eliezer, and Elliot Meyerowitz. The Relations between Cell Division and Cell Type Specification in Floral and Vegetative Meristems of Tomato and Arabidopsis. United States Department of Agriculture, February 1996. http://dx.doi.org/10.32747/1996.7613032.bard.

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Meristems were the central issue of our project. Genes that are required for cell division, cell elongation, cell proliferation and cell fate were studied in the tomato system. The analysis of the dUTPase and threonine deaminase genes, along with the dissection of their regulatory regions is completed, while that of the RNR2 and PPO genes is at an advanced stage. All these genes were isolated in our laboratory. In addition, 8 different MADS box genes were studied in transgenic plants and their genetic relevances discovered. We have also shown that a given MADS box gene can modify the polarity of cell division without affecting the fate of the organ. In vivo interaction between two MADS box genes was demonstrated and the functional dependency of the tomato agamous gene on the TM5 gene product established. We have exploited the Knotted1 meristematic gene in conjunction with tomato leaf meristematic genes to show that simple and compound leaves and, for that matter, sepals and compound leaves, are formed by two different developmental programs. In this context we have also isolated and characterized the tomato Knotted1 gene (TKnl) and studied its expression pattern. A new program in which eight different meristematic genes in tomato will be studied emerged as a result of these studies. In essence, we have shown that it is possible to study and manipulate plant developmental systems using reverse genetic techniques and have provided a wealth of new molecular tools to interested colleagues working with tomato. Similarly, genes responsible for cell division, cell proliferation and cell fate were studied in Arabidopsis floral meristems. Among these genes are the TSO1, TSO2, HANABA TARANU and UNUSUAL FLORAL ORGANS genes, each affecting in its own way the number of pattern of cell divisions, and cell fate, in developing Arabodopsis flowers. In addition, new methods have been established for the assessment of the function of regulatory gene action in the different clonal layers of developing floral meristems.
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Upadhyaya, Shrini K., Abraham Shaviv, Abraham Katzir, Itzhak Shmulevich, and David S. Slaughter. Development of A Real-Time, In-Situ Nitrate Sensor. United States Department of Agriculture, March 2002. http://dx.doi.org/10.32747/2002.7586537.bard.

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Although nitrate fertilizers are critical for enhancing crop production, excess application of nitrate fertilizer can result in ground water contamination leading to the so called "nitrate problem". Health and environmental problems related to this "nitrate problem" have led to serious concerns in many parts of the world including the United States and Israel. These concerns have resulted in legislation limiting the amount of nitrate N in drinking water to 10mg/g. Development of a fast, reliable, nitrate sensor for in-situ application can be extremely useful in dynamic monitoring of environmentally sensitive locations and applying site-specific amounts of nitrate fertilizer in a precision farming system. The long range objective of this study is to develop a fast, reliable, real-time nitrate sensor. The specific objective of this one year feasibility study was to explore the possible use of nitrate sensor based on mid-IR spectroscopy developed at UCD along with the silver halide fiber ATR (i.e. attenuated total internal reflection) sensor developed at TAU to detect nitrate content in solution and soil paste in the presence of interfering compounds. Experiments conducted at Technion and UCD clearly demonstrate the feasibility of detecting nitrate content in solutions as well as soil pastes using mid-IR spectroscopy and an ATR technique. When interfering compounds such as carbonates, bicarbonates, organic matter etc. are present special data analysis technique such as singular value decomposition (SYD) or cross correlation was necessary to detect nitrate concentrations successfully. Experiments conducted in Israel show that silver halide ATR fiber based FEWS, particularly flat FEWS, resulted in low standard error and high coefficient of determination (i.e. R² values) indicating the potential of the flat Fiberoptic Evanescent Wave Spectroscopy (FEWS) for direct determinations of nitrate. Moreover, they found that it was possible to detect nitrate and other anion concentrations using anion exchange membranes and M1R spectroscopy. The combination of the ion-exchange membranes with fiberoptices offers one more option to direct determination of nitrate in environmental systems.
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Minz, Dror, Stefan J. Green, Noa Sela, Yitzhak Hadar, Janet Jansson, and Steven Lindow. Soil and rhizosphere microbiome response to treated waste water irrigation. United States Department of Agriculture, January 2013. http://dx.doi.org/10.32747/2013.7598153.bard.

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Research objectives : Identify genetic potential and community structure of soil and rhizosphere microbial community structure as affected by treated wastewater (TWW) irrigation. This objective was achieved through the examination soil and rhizosphere microbial communities of plants irrigated with fresh water (FW) and TWW. Genomic DNA extracted from soil and rhizosphere samples (Minz laboratory) was processed for DNA-based shotgun metagenome sequencing (Green laboratory). High-throughput bioinformatics was performed to compare both taxonomic and functional gene (and pathway) differences between sample types (treatment and location). Identify metabolic pathways induced or repressed by TWW irrigation. To accomplish this objective, shotgun metatranscriptome (RNA-based) sequencing was performed. Expressed genes and pathways were compared to identify significantly differentially expressed features between rhizosphere communities of plants irrigated with FW and TWW. Identify microbial gene functions and pathways affected by TWW irrigation*. To accomplish this objective, we will perform a metaproteome comparison between rhizosphere communities of plants irrigated with FW and TWW and selected soil microbial activities. Integration and evaluation of microbial community function in relation to its structure and genetic potential, and to infer the in situ physiology and function of microbial communities in soil and rhizospere under FW and TWW irrigation regimes. This objective is ongoing due to the need for extensive bioinformatics analysis. As a result of the capabilities of the new PI, we have also been characterizing the transcriptome of the plant roots as affected by the TWW irrigation and comparing the function of the plants to that of the microbiome. *This original objective was not achieved in the course of this study due to technical issues, especially the need to replace the American PIs during the project. However, the fact we were able to analyze more than one plant system as a result of the abilities of the new American PI strengthened the power of the conclusions derived from studies for the 1ˢᵗ and 2ⁿᵈ objectives. Background: As the world population grows, more urban waste is discharged to the environment, and fresh water sources are being polluted. Developing and industrial countries are increasing the use of wastewater and treated wastewater (TWW) for agriculture practice, thus turning the waste product into a valuable resource. Wastewater supplies a year- round reliable source of nutrient-rich water. Despite continuing enhancements in TWW quality, TWW irrigation can still result in unexplained and undesirable effects on crops. In part, these undesirable effects may be attributed to, among other factors, to the effects of TWW on the plant microbiome. Previous studies, including our own, have presented the TWW effect on soil microbial activity and community composition. To the best of our knowledge, however, no comprehensive study yet has been conducted on the microbial population associated BARD Report - Project 4662 Page 2 of 16 BARD Report - Project 4662 Page 3 of 16 with plant roots irrigated with TWW – a critical information gap. In this work, we characterize the effect of TWW irrigation on root-associated microbial community structure and function by using the most innovative tools available in analyzing bacterial community- a combination of microbial marker gene amplicon sequencing, microbial shotunmetagenomics (DNA-based total community and gene content characterization), microbial metatranscriptomics (RNA-based total community and gene content characterization), and plant host transcriptome response. At the core of this research, a mesocosm experiment was conducted to study and characterize the effect of TWW irrigation on tomato and lettuce plants. A focus of this study was on the plant roots, their associated microbial communities, and on the functional activities of plant root-associated microbial communities. We have found that TWW irrigation changes both the soil and root microbial community composition, and that the shift in the plant root microbiome associated with different irrigation was as significant as the changes caused by the plant host or soil type. The change in microbial community structure was accompanied by changes in the microbial community-wide functional potential (i.e., gene content of the entire microbial community, as determined through shotgun metagenome sequencing). The relative abundance of many genes was significantly different in TWW irrigated root microbiome relative to FW-irrigated root microbial communities. For example, the relative abundance of genes encoding for transporters increased in TWW-irrigated roots increased relative to FW-irrigated roots. Similarly, the relative abundance of genes linked to potassium efflux, respiratory systems and nitrogen metabolism were elevated in TWW irrigated roots when compared to FW-irrigated roots. The increased relative abundance of denitrifying genes in TWW systems relative FW systems, suggests that TWW-irrigated roots are more anaerobic compare to FW irrigated root. These gene functional data are consistent with geochemical measurements made from these systems. Specifically, the TWW irrigated soils had higher pH, total organic compound (TOC), sodium, potassium and electric conductivity values in comparison to FW soils. Thus, the root microbiome genetic functional potential can be correlated with pH, TOC and EC values and these factors must take part in the shaping the root microbiome. The expressed functions, as found by the metatranscriptome analysis, revealed many genes that increase in TWW-irrigated plant root microbial population relative to those in the FW-irrigated plants. The most substantial (and significant) were sodium-proton antiporters and Na(+)-translocatingNADH-quinoneoxidoreductase (NQR). The latter protein uses the cell respiratory machinery to harness redox force and convert the energy for efflux of sodium. As the roots and their microbiomes are exposed to the same environmental conditions, it was previously hypothesized that understanding the soil and rhizospheremicrobiome response will shed light on natural processes in these niches. This study demonstrate how newly available tools can better define complex processes and their downstream consequences, such as irrigation with water from different qualities, and to identify primary cues sensed by the plant host irrigated with TWW. From an agricultural perspective, many common practices are complicated processes with many ‘moving parts’, and are hard to characterize and predict. Multiple edaphic and microbial factors are involved, and these can react to many environmental cues. These complex systems are in turn affected by plant growth and exudation, and associated features such as irrigation, fertilization and use of pesticides. However, the combination of shotgun metagenomics, microbial shotgun metatranscriptomics, plant transcriptomics, and physical measurement of soil characteristics provides a mechanism for integrating data from highly complex agricultural systems to eventually provide for plant physiological response prediction and monitoring. BARD Report
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9

Lichter, Amnon, Joseph L. Smilanick, Dennis A. Margosan, and Susan Lurie. Ethanol for postharvest decay control of table grapes: application and mode of action. United States Department of Agriculture, July 2005. http://dx.doi.org/10.32747/2005.7587217.bard.

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Abstract:
Original objectives: Dipping of table grapes in ethanol was determined to be an effective measure to control postharvest gray mold infection caused by Botrytis cinerea. Our objectives were to study the effects of ethanol on B.cinerea and table grapes and to conduct research that will facilitate the implementation of this treatment. Background: Botrytis cinerea is known as the major pathogen of table grapes in cold storage. To date, the only commercial technology to control it relied on sulfur dioxide (SO₂) implemented by either fumigation of storage facilities or from slow release generator pads which are positioned directly over the fruits. This treatment is very effective but it has several drawbacks such as aftertaste, bleaching and hypersensitivity to humans which took it out of the GRAS list of compounds and warranted further seek for alternatives. Prior to this research ethanol was shown to control several pathogens in different commodities including table grapes and B. cinerea. Hence it seemed to be a simple and promising technology which could offer a true alternative for storage of table grapes. Further research was however required to answer some practical and theoretical questions which remained unanswered. Major conclusions, solutions, achievements: In this research project we have shown convincingly that 30% ethanol is sufficient to prevent germination of B. cinerea and kill the spores. In a comparative study it was shown that Alternaria alternata is also rather sensitive but Rhizopus stolonifer and Aspergillus niger are less sensitive to ethanol. Consequently, ethanol protected the grapes from decay but did not have a significant effect on occurrence of mycotoxigenic Aspergillus species which are present on the surface of the berry. B. cinerea responded to ethanol or heat treatments by inducing sporulation and transient expression of the heat shock protein HSP104. Similar responses were not detected in grape berries. It was also shown that application of ethanol to berries did not induce subsequent resistance and actually the berries were slightly more susceptible to infection. The heat dose required to kill the spores was determined and it was proven that a combination of heat and ethanol allowed reduction of both the ethanol and heat dose. Ethanol and heat did not reduce the amount or appearance of the wax layers which are an essential component of the external protection of the berry. The ethanol and acetaldehyde content increased after treatment and during storage but the content was much lower than the natural ethanol content in other fruits. The efficacy of ethanol applied before harvest was similar to that of the biological control agent, Metschnikowia fructicola, Finally, the performance of ethanol could be improved synergistically by packaging the bunches in modified atmosphere films which prevent the accumulation of free water. Implications, both scientific and agricultural: It was shown that the major mode of action of ethanol is mediated by its lethal effect on fungal inoculum. Because ethanol acts mainly on the cell membranes, it was possible to enhance its effect by lowering the concentration and elevating the temperature of the treatment. Another important development was the continuous protection of the treated bunches by modified atmosphere that can solve the problem of secondary or internal infection. From the practical standpoint, a variety of means were offered to enhance the effect of the treatment and to offer a viable alternative to SO2 which could be instantly adopted by the industry with a special benefit to growers of organic grapes.
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10

Brydie, Dr James, Dr Alireza Jafari, and Stephanie Trottier. PR-487-143727-R01 Modelling and Simulation of Subsurface Fluid Migration from Small Pipeline Leaks. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), May 2017. http://dx.doi.org/10.55274/r0011025.

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The dispersion and migration behavior of hydrocarbon products leaking at low rates (i.e. 1bbl/day and 10 bbl/day) from a pipeline have been studied using a combination of experimental leakage tests and numerical simulations. The focus of this study was to determine the influence of subsurface engineered boundaries associated with the trench walls, and the presence of a water table, upon the leakage behavior of a range of hydrocarbon products. The project numerically modelled three products including diesel, diluted bitumen (dilbit) and gasoline; which were chosen to span a range of fluid types and viscosities. Laboratory simulations of leakage were carried out for the most viscous product (i.e. dilbit) in order to capture plume dispersion in semi-real time, and to allow numerical predictions to be assessed against experimental data. Direct comparisons between observed plume dimensions over time and numerically predicted behavior suggested a good match under low moisture conditions, providing confidence that the numerical simulation was sufficiently reliable to model field-scale applications. Following a simulated two year initialization period, the leakage of products, their associated gas phase migration, thermal and geomechanical effects were simulated for a period of 365 days. Comparisons between product leakage rate, product type and soil moisture content were made and the spatial impacts of leakage were summarized. Variably compacted backfill within the trench, surrounded by undisturbed and more compacted natural soils, results porosity and permeability differences which control the migration of liquids, gases, thermal effects and surface heave. Dilbit migration is influenced heavily by the trench, and also its increasing viscosity as it cools and degases after leakage. Diesel and gasoline liquid plumes are also affected by the trench structure, but to a lesser extent, resulting in wider and longer plumes in the subsurface. In all cases, the migration of liquids and gases is facilitated by higher permeability zones at the base of the pipe. Volatile Organic Compounds (VOCs) migrate along the trench and break through at the surface within days of the leak. Temperature changes within the trench may increase due liquid migration, however the change in predicted temperature at the surface above the leak is less than 0.5�C above background. For gasoline, the large amount of degassing and diffusion through the soil results in cooling of the soil by up to 1�C. Induced surface displacement was predicted for dilbit and for one case of diesel, but only in the order of 0.2cm above baseline. Based upon the information gathered, recommendations are provided for the use and placement of generic leak detection sensor types (e.g liquid, gas, thermal, displacement) within the trench and / or above the ground surface. The monitoring locations suggested take into account requirements to detect pipeline leakage as early as possible in order to facilitate notification of the operator and to predict the potential extent of site characterization required during spill response and longer term remediation activities.
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