Letteratura scientifica selezionata sul tema "Soluble microbial products"
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Articoli di riviste sul tema "Soluble microbial products"
1
Chipasa, K. B., e K. Mędrzycka. "Adaptive response of microbial communities to soluble microbial products". Journal of Industrial Microbiology & Biotechnology 31, n. 8 (13 agosto 2004): 384–90. http://dx.doi.org/10.1007/s10295-004-0161-6.
Testo completo
2
Fang, Herbert H. P., e Xiao-Shan Jia. "Soluble microbial products (SMP) of acetotrophic methanogenesis". Bioresource Technology 66, n. 3 (dicembre 1998): 235–39. http://dx.doi.org/10.1016/s0960-8524(98)00056-x.
Testo completo
3
Noguera, Daniel R., Nobuo Araki e Bruce E. Rittmann. "Soluble microbial products (SMP) in anaerobic chemostats". Biotechnology and Bioengineering 44, n. 9 (5 novembre 1994): 1040–47. http://dx.doi.org/10.1002/bit.260440904.
Testo completo
4
Shi, Weiwei, Huanlong Peng, Jie Wu, Meirou Wu, Da Li, Wenjia Xie, Jian Ye, Liang Xu, Yongmei Liang e Wei Liu. "Adsorption of soluble microbial products by sediments". Ecotoxicology and Environmental Safety 169 (marzo 2019): 874–80. http://dx.doi.org/10.1016/j.ecoenv.2018.11.005.
Testo completo
5
Boero, V. J., W. W. Eckenfelder e A. R. Bowers. "Soluble Microbial Product Formation in Biological Systems". Water Science and Technology 23, n. 4-6 (1 febbraio 1991): 1067–76. http://dx.doi.org/10.2166/wst.1991.0558.
Testo completoAbstract (sommario):
The formation of soluble microbial products was evaluated in batch reactors using radiolabeled 14C-phenol and 14C-glucose. Soluble microbial products, SMP, resulted from intermediates or end products of substrate degradation and endogenous cell decomposition. On an organic carbon basis, the SMP produced after A8 hours averaged 1A.7 (±3.7) percent of the initial phenol and 3.1 (±0.4) percent of the initial glucose. The SMP were categorized as substrate utilization products, having a biodegradable and non-biodegradable fraction, and biomass associated products, which were only non-biodegradable. A model was developed based on kinetic relationships between several macroscopic compartments, which consisted of the initial substrate, cell mass, and the three SMP categories. Based on the experimental data, zero and first order kinetics were sufficient to describe the disappearance of the initial substrates and the net SMP, i.e., total SMP produced less SMP biodegraded to yield CO2 and/or new biomass. Both phenol and glucose adhered to the same kinetic model, but the rate constants were considerably different.
6
Kuo, Wen-Chien, Mark A. Sneve e Gene F. Parkin. "Formation of soluble microbial products during anaerobic treatment". Water Environment Research 68, n. 3 (maggio 1996): 279–85. http://dx.doi.org/10.2175/106143096x127712.
Testo completo
7
Namkung, Eun, e Bruce E. Rittmann. "Soluble microbial products (SMP) formation kinetics by biofilms". Water Research 20, n. 6 (giugno 1986): 795–806. http://dx.doi.org/10.1016/0043-1354(86)90106-5.
Testo completo
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Ichihashi, Osamu, Hiroyasu Satoh e Takashi Mino. "Effect of soluble microbial products on microbial metabolisms related to nutrient removal". Water Research 40, n. 8 (maggio 2006): 1627–33. http://dx.doi.org/10.1016/j.watres.2006.01.047.
Testo completo
9
Wang, Xiao-Mao, e T. David Waite. "Retention of soluble microbial products in submerged membrane bioreactors". Desalination and Water Treatment 6, n. 1-3 (giugno 2009): 131–37. http://dx.doi.org/10.5004/dwt.2009.658.
Testo completo
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Fenu, A., T. Wambecq, C. Thoeye, G. De Gueldre e B. Van de Steene. "Modelling soluble microbial products (SMPs) in a dynamic environment". Desalination and Water Treatment 29, n. 1-3 (maggio 2011): 210–17. http://dx.doi.org/10.5004/dwt.2011.2095.
Testo completoTesi sul tema "Soluble microbial products"
1
Aquino, SeÌrgio Francisco de. "Formation of soluble microbial products (SMP) in anaerobic reactors during stress conditions". Thesis, Imperial College London, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.405566.
Testo completo
2
Murthy, Sudhir N. "Bioflocculation: Implications for Activated Sludge Properties and Wastewater Treatment". Diss., Virginia Tech, 1998. http://hdl.handle.net/10919/30647.
Testo completoAbstract (sommario):
Studies were conducted to determine the role of bioflocculation in the activated sludge unit processes. Laboratory and full-scale studies revealed that bioflocculation is important in determining settling, dewatering, effluent and digested sludge properties (activated sludge properties) and may be vital to the function of all processes related to the above properties. In these studies, it was shown that divalent cations such as calcium and magnesium improved activated sludge properties, whereas monovalent cations such as sodium, potassium and ammonium ions were detrimental to these properties. The divalent cations promoted bioflocculation through charge bridging mechanisms with negatively charged biopolymers (mainly protein and polysaccharide). It was found that oxidized iron plays a major role in bioflocculation and determination of activated sludge properties through surface interactions between iron and biopolymers. Oxidized iron was effective in removing colloidal biopolymers from solution in coagulation and conditioning studies. The research included experiments evaluating effects of potassium and ammonium ions on settling and dewatering properties; effects of magnesium on settling properties; effects of sodium, potassium, calcium and magnesium on effluent quality; effect of solids retention time on effluent quality; and evaluation of floc properties during aerobic and thermophilic digestion. A floc model is proposed in which calcium, magnesium and iron are important to bioflocculation and the functionality of aeration tanks, settling tanks, dewatering equipment and aerobic or anaerobic digesters. It is shown that activated sludge floc properties affect wastewater treatment efficiency.Ph. D.
3
Robles, Martínez Ángel. "Modelling, simulation and control of the filtration process in a submerged anaerobic membrane bioreactor treating urban wastewater". Doctoral thesis, Editorial Universitat Politècnica de València, 2013. http://hdl.handle.net/10251/34102.
Testo completoAbstract (sommario):
El reactor anaerobio de membranas sumergidas (SAnMBR) está considerado como tecnología
candidata para mejorar la sostenibilidad en el sector de la depuración de aguas residuales,
ampliando la aplicabilidad de la biotecnología anaerobia al tratamiento de aguas residuales de
baja carga (v.g. agua residual urbana) o a condiciones medioambientales extremas (v.g. bajas
temperaturas de operación). Esta tecnología alternativa de tratamiento de aguas residuales es
más sostenible que las tecnologías aerobias actuales ya que el agua residual se transforma en
una fuente renovable de energía y nutrientes, proporcionando además un recurso de agua
reutilizable. SAnMBR no sólo presenta las principales ventajas de los reactores de membranas
(i.e. efluente de alta calidad, y pocas necesidades de espacio), sino que también presenta las
principales ventajas de los procesos anaerobios. En este sentido, la tecnología SAnMBR
presenta una baja producción de fangos debido a la baja tasa de crecimiento de los
microorganismos implicados en la degradación de la materia orgánica, presenta una baja
demanda energética debido a la ausencia de aireación, y permite la generación de metano, el
cual representa una fuente de energía renovable que mejora el balance energético neto del
sistema. Cabe destacar el potencial de recuperación de nutrientes del agua residual bien cuando
el efluente es destinado a irrigación directamente, o bien cuando debe ser tratado previamente
mediante tecnologías de recuperación de nutrientes.
El objetivo principal de esta tesis doctoral es evaluar la viabilidad de la tecnología SAnMBR
como núcleo en el tratamiento de aguas residuales urbanas a temperatura ambiente. Por lo tanto,
esta tesis se centra en las siguientes tareas: (1) implementación, calibración y puesta en marcha
del sistema de instrumentación, control y automatización requerido; (2) identificación de los
parámetros de operación clave que afectan al proceso de filtración; (3) modelación y simulación
del proceso de filtración; y (4) desarrollo de estrategias de control para la optimización del
proceso de filtración minimizando los costes de operación.
En este trabajo de investigación se propone un sistema de instrumentación, control y
automatización para SAnMBR, el cual fue esencial para alcanzar un comportamiento adecuado
y estable del sistema frente a posibles perturbaciones. El comportamiento de las membranas fue
comparable a sistemas MBR aerobios a escala industrial. Tras más de dos años de operación
ininterrumpida, no se detectaron problemas significativos asociados al ensuciamiento
irreversible de las membranas, incluso operando a elevadas concentraciones de sólidos en el
licor mezcla (valores de hasta 25 g·L-1
). En este trabajo se presenta un modelo de filtración
(basado en el modelo de resistencias en serie) que permitió simular de forma adecuada el proceso de filtración. Por otra parte, se propone un control supervisor basado en un sistema
experto que consiguió reducir el consumo energético asociado a la limpieza física de las
membranas, un bajo porcentaje de tiempo destinado a la limpieza física respecto al total de
operación, y, en general, un menor coste operacional del proceso de filtración.
Esta tesis doctoral está integrada en un proyecto nacional de investigación, subvencionado por
el Ministerio de Ciencia e Innovación (MICINN), con título ¿Modelación de la aplicación de la
tecnología de membranas para la valorización energética de la materia orgánica del agua
residual y la minimización de los fangos producidos¿ (MICINN, proyecto CTM2008-06809-
C02-01/02). Para obtener resultados representativos que puedan ser extrapolados a plantas
reales, esta tesis doctoral se ha llevado a cabo utilizando un sistema SAnMBR que incorpora
módulos comerciales de membrana de fibra hueca. Además, esta planta es alimentada con el
efluente del pre-tratamiento de la EDAR del Barranco del Carraixet (Valencia, España).Robles Martínez, Á. (2013). Modelling, simulation and control of the filtration process in a submerged anaerobic membrane bioreactor treating urban wastewater [Tesis doctoral]. Editorial Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/34102
Alfresco
Premiado
4
Lee, Chou-Ken, e 李宙耕. "Characteristics of Soluble Microbial Products in Activated Sludge". Thesis, 2005. http://ndltd.ncl.edu.tw/handle/40894239441785583346.
Testo completoAbstract (sommario):
碩士朝陽科技大學
環境工程與管理系碩士班
93
Biological wastewater treatment processes employed various microorganisms with their metabolism to reduce and degrade the organic substances and nutrients in wastewater. Some persistent chemical compounds could be processed by cometabolism. It is quite difficult to remove the residual COD in the effluent which included soluble microbial products (SMPs). The productions and characteristics of the SMPs were functions of the microbial species, growth environment, rate of substrate utilization, temperature, pH and oxidation/reduction potential, etc. The substances of SMPs were essential not only for meeting the standard of effluent but also for reducing the organics concentration to improve recycle potential of wastewater. In this study, seeding microorganisms were derived from the sludge of wastewater treatment in the Chaoyang University of Technology. This sludge was acclimated in a sequencing batch reactor which was operated at SRT of 10 days. Acclimated sludge was collected for aerobic, anoxic and anaerobic batch experiments with continued load and endogenous respiration to investigate the characteristics of SMPs production in activated sludge. Experimental results demonstrated that the amount of utilization associated products (UAP) in aerobic situation were about 4.2 mg DOC/g SS which was lower than the amount in the anoxic or anaerobic situation. After 12 hours, the amount of UAP was increased to 29.2 mg DOC/g SS. As time goes by, the amount was decrease to 12 mg DOC/g SS. Apparently, the organism needed long time for SMPs degradation in aerobic environment. In anoxic environment, the production of SMPs was similar with anaerobic environment, but after 2 hours, the variation of SMPs in anoxic environment was slight. After 24 hours reaction, the amount was decrease to 15.3 mg DOC/g SS. In anaerobic condition, the amount of SMPs was uppermost during 4-6 hour reaction, then, it was decrease to 14.5 mg DOC/g SS. It showed that the production of SMPs was quick; moreover, the rate of biodegradation was also quick. In the biomass associated products (BAP), the production of SMPs was represented as DOC. The production of SMPs in aerobic environment was increased initially and then reached to a stable value. The amount was increased from 1.4 mg DOC/g SS to 7.6 mg DOC/g SS. Comparing with anoxic and anaerobic environment, the behavior of SMPs production was different. The molecular weight of major UAP in the initial stage was higher than 100 kDa. Then, the organic substances were decomposed; the compounds of molecular weight lower than 30 kDa was formed. The changes of molecular weight distribution of BAP under different environments showed that more quantity of compounds with lower molecular was present at the initial stage. Due to without feeding of substances for microorganism, some microorganisms were decomposed because of endogenous respiration decade, and some released compounds were consumed by the other microorganisms. The residual was mainly composed of high molecular weight compounds.
5
Lin, Tung-Liang, e 林棟樑. "Characteristics of Soluble Microbial Products in Activated Sludge". Thesis, 2006. http://ndltd.ncl.edu.tw/handle/s5a9u8.
Testo completoAbstract (sommario):
碩士朝陽科技大學
環境工程與管理系碩士班
94
Biological wastewater treatment processes employed various microorganisms to reduce and degrade organic substances in wastewater. However, it was difficult to remove the residual organics in the effluent, which usually included the soluble microbial products (SMPs). Therefore, the SMPs were essential not only for meeting the standard of effluent but also for improving potential of wastewater reuse. In this study, the activated sludge was acclimated in a sequencing batch reactor (SBR), which operated at different SRT condition. The acclimated sludge was used for batch experiments to investigate the characteristics of SMPs production in activated sludge. The results showed that in the conditions of anoxic and anaerobic, and the condition of loading, the production of SMPs would be increased because of the with SRT increasing after reacting for 6 hours in the continuous loading under anoxic and anaerobic conditions. In the condition of endogenous, the correlation between the SMPs production and showed less influence when the SRT changing was not evident. That showed that t The production of SMPs would be was limited obviously and below 8 mg C/g MLSS. In the continuous loading batch experiments, the analysis of molecular weight distribution (MWD) of SMPs showed that , the molecular weight of the most SMPs was higher than 100 kDa at the initial stage; and then it was down to lower than 30 kDa. However, the molecular weight of the most SMPs was lower than 30 kDa in the condition of endogenous at the initial stage; finally, the higher molecular weight substances became the major parts of SMPs in the endogenous experiments.
6
Kuo, Chin-Sheng, e 郭謹陞. "Effect of Soluble Microbial Products Hydrophobicity on Membrane Fouling". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/52575062981375634328.
Testo completoAbstract (sommario):
碩士國立臺灣大學
環境工程學研究所
99
Biological treatment systems with different sludge retention time (SRT), fixed carrier biological system (FCBS) and activated sludge process (ASP) were studied. Membrane permeate flux fluctuation was constantly monitored. The effect of soluble microbial products (SMP) hydrophobicity on membrane fouling was investigated with the use of DAX-8 resin to isolate hydrophilic and hydrophobic compounds in water samples, with total organic compound (TOC), carbohydrate and protein were taken as quantitative parameters for hydrophobicity analyze. Two different membrane pore sizes (30 kDa and 100 kDa) were used in membrane operation. Fiber filter with pore size of 0.1 μm was applied as pretreatment in order to eliminate the impact of suspended solids in water samples on membrane fouling. Effluents from different biological treatment systems (FCBS and ASP) were run through membrane process and it was observed that FCBS effluents contained higher SMP concentrations and caused more significant membrane fouling than effluents from ASP system. The result also suggested that membrane fouling increase with SMP concentrations. Greater permeate flux decline was observed in membrane process with larger pore size for both FCBS and ASP system. Hydrophobicity analysis indicated hydrophilic contents are the major components of SMP, and the result also indicated that membrane retained more hydrophilic contents than hydrophobic contents. In conclusion, it can be suggested membrane fouling was mainly affected by hydrophilic substances.
7
Chen, Yi-min, e 陳依旻. "Characteristics and effects of soluble microbial products in membrane bioreactors". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/97562478831002072721.
Testo completoAbstract (sommario):
碩士國立中央大學
環境工程研究所
100
The purpose of this study was to investigate the characteristics and effects of soluble microbial products (SMP) produced from pre-treatment processes and membrane bioreactors for treating different types of wastewater, including TFT-LCD industry wastewater(TFT-LCD), domestic wastewater(DW), and wool processing industry wastewater(WPI). The samples were analysed with water quality and the composition of SMP for raw wastewater, the influent of MBR, the inside of MBR and the effluent of MBR. After that, the effluent of MBR was filtrated by UF membrane to observe the properties of SMP. The result shows that TFT-LCD was a high concentration of ammonia-nitrogen wastewater. The removal efficiencies of organic compounds are more than 70% for pre-treatment process. The efficiency was increased to 80% and the MW distribution was changed from between >3kDa and 6kDa to <3kDa after the treatment of MBR. Due to the sufficiency of substrate in MBR, the component of SMP was formed with the major of UAP as well as there was a plenty of the carbohydrate and protein in the effluent of MBR. On the treatment of DW wastewater, which was easily biodegradable, the removal efficiency of organic compounds was 60-80% and MW distribution was changed from >3kDa to <3kDa after the treatment of MBR. Although the removal of organic compounds with double bond was only 5%, the concentration of SMP was low as well as the major component was humic substances analysed by EEM. The component of SMP may infer the major of BAP from the contrast with literature. On the treatment of WPI wastewater, which was a refractory organic wastewater, the removal efficiencies of SCOD and DOC are about 90% for pre-treatment process. These organic compounds were further degraded to acquire another 50% removal efficiency and a little removal of double-bond substance. Consequently, there are more residual humic acids, SMP, high SCOD and DOC concentration in the effluent of MBR. However, the major region of MW distribution was <208Da and the component of SMP was the type of BAP. On the filtration of 30kDa UF membrane, there is no cake layer on membrane surface and permeate flux decline slowly at the filtration of MBR effluent for TFT-LCD. Nevertheless, the observance found protein-like material and carboxylic acid functional group on the surface of UF membrane. This revealed that most of hydrophobic protein of SMP was rejected by membrane, on the other hand, carbohydrate and humic acid material was permeate into the effluent of UF.
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"Formation of soluble microbial products (SMP) in anaerobic reactors during stress conditions". Tese, Biblioteca Digital de Teses e Dissertações do IBICT, 2004. http://tede.ibict.br/tde_busca/arquivo.php?codArquivo=223.
Testo completo
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Tsai, Bor Nein, e 蔡博年. "Characteristics, Coagulation and Filtration of Soluble Microbial Products and Extracellular Polymeric Substances". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/48063959260932857614.
Testo completoAbstract (sommario):
碩士國立臺灣大學
化學工程學研究所
95
The dissolved organic matters (DOM) in the soluble microbial products (SMP), loosely bound extracellular polymeric substances (LBEPS), and tightly bound extracellular polymeric substances (TBEPS) extracted from a wastewater sludge were fractionated using size exclusion chromatography, and were characterized by ultraviolet absorbance at 230, 254, and 280 nm, the dissolved organic carbon (DOC) contents, and the excitation-emission-matrix (EEM) spectra. The DOM of molecular weight (MW) > 20000 Da accounted for 33% for SMP, which incorporated proteins of high aromaticity, and 22% for both LBEPS and TBEPS, which were composed of organic acids-like substances and proteins respectively. Polyaluminum chloride (PACl) coagulation could effectively remove this fraction of DOM. On the other hand, the DOM of MW< 1000 Da were mostly non-aromatic organic acids (and probably also polysaccharides) of low aromaticity for SMP and both EPS, and were hardly removed by PACl coagulation. Based on the EEM and UV absorbance data, proteins of high MW and humic substances were easily removed by PACl coagulation. The present study indicates that, although the chemical characteristics of DOM in SMP and LBEPS were alike, but not identical. The DOM in TBEPS differed significantly from SMP or LBEPS based either on DOC distributions or on EEM fingerprints.
10
Chien, Chu-yu, e 簡筑伃. "Effects of operational factors on trentment efficiency and soluble microbial products in Membrane". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/38501127128811826314.
Testo completoAbstract (sommario):
碩士國立中央大學
環境工程研究所
101
The objectives of this study were to investigate the treatment efficiency of synthetic wastewater by membrane bioreactor (MBR) and to elucidate the characteristics of soluble microbial products (SMP) at different operation parameters, including sludge retention time (SRT) 10, 20 and 40 days and influent COD concentration 300, 600 and 900 mg/L. The results showed that the optimum treatment efficiency was occurred at operation parameter SRT 20 days. On the characteristic effect of SMP, the major component of SMP was carbohydrate and the most utilization substrate for biomass in the MBR was protein, however, the carbohydrate was easily to block the membrane filtration than the protein resulting to the concentration accumulated in the tank of MBR. Owing to the ratio of SCODSMP/SCOD and DOCSMP/DOC in the effluent grater than 90%, that is, the main contains of SCOD and DOC is SMP in the effluent. Furthermore, the concentration of SCODSMP and DOCSMP were increased from the MBR to the effluent showed that the small molecular of SMP, which belonged to UAP (Utilization-Associated Products), was easily to pass through the membrane. On the analysis of EEM, the intensity of EEM spectra of the effluent was smaller than in the tank revealed that larger molecular of SMP, which belonged to BAP (Biomass-Associated Products), was blocked by this membrane. The treatment efficiency of UV254, SCODSMP, DOCSMP, SCODSMP/SCOD and DOCSMP/DOC was increased with the increase of SRT. This phenomenon revealed that the substrate utilization is increased with the growth of biomass resulting in improve the release of the double bond material and SMP. Because of the excessive biomass growth and the carbon source was insufficient, therefore, SMP was utilized as the food for biomass so that the concentration of SMP was dropt down at SRT 40 days. Nevertheless, the utilization of protein and the generation of carbohydrate were improved so that the ratio of protein to carbohydrate (P/C) was decrease. On the molecular weight distribution, the range of molecular weight distribution of UAP and BAP had a slight increase when the SRT increased. In addition, the concentration of SMP-like analyzed by EEM spectrum in MBR was increased with the increase of SRT due to the decay of the excessive biomass as well as the compositions of SMP was raised in the effluent. The treatment efficiency was initially increased and then decreased corresponding to the variation of influent COD concentration 300, 600 and 900 mg/L. Simultaneously, the concentration of SCODSMP and DOCSMP also increased when the substrate was sufficient for the metabolism of biomass in MBR. On the molecular weight distribution, the major component of SMP was UAP, however, the concentration of BAP and UAP was similar at influent COD concentration 900 mg/L. Furthermore, the range of molecular weight distribution of BAP and UAP had broadened with the increase of the influent COD concentration. Finally, the concentration of SMP-like analyzed by EEM spectra in MBR was increased with the increase of influent COD concentration due to the substrate was sufficient for the metabolism of biomass in MBR. Keyword: membrane bioreactor (MBR), soluble microbial products (SMP), sludge retention time (SRT), influent COD concentration
Capitoli di libri sul tema "Soluble microbial products"
1
Ni, Bing-Jie. "Fractionating and Determination of the Soluble Microbial Products". In Formation, characterization and mathematical modeling of the aerobic granular sludge, 171–201. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-31281-6_8.
Testo completo
2
Morgan, Lynette. "Greenhouse produce quality and assessment." In Hydroponics and protected cultivation: a practical guide, 246–67. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789244830.0246.
Testo completoAbstract (sommario):
Abstract 'Quality' of greenhouse and hydroponic produce implies suitability for a particular purpose or the degree to which certain set standards are met. Aspects of produce quality may encompass sensory properties (appearance, texture, taste and aroma), nutritive values, chemical constituents, mechanical properties, functional properties and defects. Quality standards and testing methods have been developed for most commercial crops to help ensure consumers receive produce of a suitable standard. These quality standards can range from basic grading for removal of damaged produce and for size, shape, weight and overall appearance, to analytical testing for compositional factors such as acidity, volatiles, dry matter, starch and sugars, toxins, vitamins and minerals, and others. This chapter discusses the components of crop quality, quality improvement, cultural practices to improve greenhouse produce quality (nutrient solution electrical conductivity levels, salinity and deficit irrigation), environmental conditions (including light and temperature) affecting quality of greenhouse crops, role of genetics in the quality of greenhouse-grown produce, microbial quality and food safety. Different quality testing and grading methods are described such as colour analysis, total soluble solids (Brix) testing, sensory evaluation of compositional quality, volatiles testing (aroma), texture and firmness quality assessment.
3
Morgan, Lynette. "Greenhouse produce quality and assessment." In Hydroponics and protected cultivation: a practical guide, 246–67. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789244830.0013.
Testo completoAbstract (sommario):
Abstract 'Quality' of greenhouse and hydroponic produce implies suitability for a particular purpose or the degree to which certain set standards are met. Aspects of produce quality may encompass sensory properties (appearance, texture, taste and aroma), nutritive values, chemical constituents, mechanical properties, functional properties and defects. Quality standards and testing methods have been developed for most commercial crops to help ensure consumers receive produce of a suitable standard. These quality standards can range from basic grading for removal of damaged produce and for size, shape, weight and overall appearance, to analytical testing for compositional factors such as acidity, volatiles, dry matter, starch and sugars, toxins, vitamins and minerals, and others. This chapter discusses the components of crop quality, quality improvement, cultural practices to improve greenhouse produce quality (nutrient solution electrical conductivity levels, salinity and deficit irrigation), environmental conditions (including light and temperature) affecting quality of greenhouse crops, role of genetics in the quality of greenhouse-grown produce, microbial quality and food safety. Different quality testing and grading methods are described such as colour analysis, total soluble solids (Brix) testing, sensory evaluation of compositional quality, volatiles testing (aroma), texture and firmness quality assessment.
4
Lee, Kibaek, Seonki Lee, Jaewoo Lee, Xiaolei Zhang e Sang Hyun Lee. "Roles of soluble microbial products and extracellular polymeric substances in membrane fouling". In Current Developments in Biotechnology and Bioengineering, 45–79. Elsevier, 2020. http://dx.doi.org/10.1016/b978-0-12-819809-4.00003-6.
Testo completo
5
Rajwar, Deepika, Mamta Bisht e J. P. N. Rai. "Wastewater Treatment". In Advances in Environmental Engineering and Green Technologies, 162–74. IGI Global, 2018. http://dx.doi.org/10.4018/978-1-5225-3126-5.ch010.
Testo completoAbstract (sommario):
In recent years, stringent discharge standards prior to the release of effluent into the water bodies have led to implementation of diverse advanced biological treatment processes in various industries. Biological treatment is a fundamental part of industrial wastewater treatment, contains soluble inorganic/organic pollutants. Being a cost-effective process, biological treatment has an economic advantage over chemical and physical processes. It employs a range of microorganisms which as a community form a microbial biofilm. Microbial biofilm provides a diverse range of micro-niches to microbial communities and protection from physical agitation to support metabolic potential and functional stability. Currently, biofilms are applied in wastewater treatment, degradation of toxic waste in water and soil and production of various commercial products. Intensive exploration has proved the importance of biofilm as a highly promising biotechnology, especially in wastewater treatment.
6
Sposito, Garrison. "Soil Humus". In The Chemistry of Soils. Oxford University Press, 2016. http://dx.doi.org/10.1093/oso/9780190630881.003.0007.
Testo completoAbstract (sommario):
Biomoleculesare compounds synthesized to sustain the life cycles of organisms. In soil humus, they are usually products of litter degradation, root excretion, and microbial metabolism, ranging in molecular structure from simple organic acids to complex biopolymers. Organic acids are among the best-characterized biomolecules. Table 3.1 lists five aliphatic (meaning the C atoms are arranged in open-chain structures) organic acids associated commonly with the soil microbiome. These acids contain the unit R—COOH, where COOH is the carboxyl groupand R represents either H or an organic moiety. The carboxyl group can lose its proton easily within the normal range of soil pH (see the third column of Table 3.1) and so is an example of a Brønsted acid. The released proton, in turn, can attack soil minerals to induce their decomposition (see Eq. 1.2), whereas the carboxylate anion (COO-) can form soluble complexes with metal cations, such as Al3+, that are released by mineral weathering [for example, in Eq. 1.7, rewrite oxalate, C2O42-, as (COO-) 2]. The total concentration of organic acids in the soil solution ranges up to 5 mM. These acids tend to have very short lifetimes because of biocycling, but they abide as a component of soil humus, especially its water-soluble fraction, because they are produced continually by microorganisms and plant roots. Formic acid (methanoic acid), the first entry in Table 3.1, is a monocarboxylic acid produced by bacteria and found in the root exudates of maize. Acetic acid (ethanoic acid) also is produced microbially—especially under anaerobic conditions—and is found in root exudates of grasses and herbs. Formic and acetic acid concentrations in the soil solution range from 2 to 5 mM. Oxalic acid (ethanedioic acid), which is ubiquitous in soils, and tartaric acid (D- 2,3-dihydroxybutanedioic acid) are dicarboxylic acids produced by fungi and excreted by plant roots; their soil solution concentrations range from 0.05 to 1 mM. The tricarboxylic citric acid (2-hydroxypropane- 1,2,3-tricarboxylic acid) is also produced by fungi and excreted by plant roots. Its soil solution concentration is less than 0.05 mM.
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Tinker, Peter B., e Peter Nye. "Microbiological Modification of the Rhizosphere". In Solute Movement in the Rhizosphere. Oxford University Press, 2000. http://dx.doi.org/10.1093/oso/9780195124927.003.0012.
Testo completoAbstract (sommario):
The general questions of root/shoot ratio, allocation of carbon to the root system, and root system dynamics are discussed in chapter 9, and the detailed root structure in chapter 5. Root-derived carbon forms the substrate for rhizosphere and symbiotic organisms, and hence leads to the increase in their population densities close to or in the root. Some of the carbon compounds from the root have specific chemical effects also (see chapter 7). Both quantity and composition of these materials need to be known if their effects are to be understood, and we discuss this subject here. The terminology of these materials is rather confused. The collective name for the injection of plant-derived carbon into the soil around living roots is ‘rhizodeposition’, but this has been used in different ways; for example, it may include root-respired carbon dioxide (Whipps 1990), but Darrah (1996) excludes carbon dioxide. The various forms include (Rovira et al. 1979; Lambers 1987; Whipps 1990) solid tissues lost from the root during growth; mucigel and debris from root surfaces and root cap; low-molecular-weight organic compounds in solution; carbon dioxide produced by root respiration for maintenance and for growth; faunal grazing of root tissues; and carbon transferred into symbionts, such as mycorrhizas and rhizobia. Some authors subdivide certain of these classes further. ‘Rhizodeposition’ is loss from a functioning root, but over a longer period the death and decomposition of whole roots deposits large quantities of carbon into the soil, which continues to act as a more resistant microbial substrate (see chapter 9). All of these materials ultimately are converted to carbon dioxide (except for material formed into stable soil organic matter) and this is difficult to separate from carbon dioxide produced directly by root respiration. The main issue here is how the various forms of deposition alter the ability of the living root system to absorb nutrients. We use the following terms for clarity, and because they relate to the practical means whereby these materials are quantified. As the rhizosphere situation is very dynamic, the results obtained will depend upon the timescale considered. (a) Exudates: soluble low-molecular-weight material that comes directly from the living root (microbial metabolites may be similar, but are excluded).
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Watson, J. E., e R. F. Harris. "Diffusion-Linked Microbial Metabolism in the Vadose Zone". In Vadose Zone Hydrology. Oxford University Press, 1999. http://dx.doi.org/10.1093/oso/9780195109900.003.0011.
Testo completoAbstract (sommario):
Figure 7.1 is a schematic of nutrient and contaminant transformations and cycling in the vadose zone. As detailed in Harris and Arnold (1995), higher plants take up C, N, P, and S in their most oxidized forms and use, via photosynthesis, the Sun’s energy and low-energy electrons from the oxygen in water to convert the oxidized forms of these essential elements into the relatively high energy reduced forms comprising plant biomass. Following plant death, the biomass residues enter the soil and are attacked by soil organisms as a source of food. The plant residues are depolymerized and the reduced, high-energy monomers are assimilated in part into soil organism biomass, and in part are used as electron donors to combine with the most thermodynamically efficient electron acceptors for dissimilatory energy generation to drive growth and maintenance reactions. In aerobic zones, oxygen is the preferred electron acceptor as long as it is nonlimiting. Death of soil organisms produces dead biomass which re-enters the biological reactor. Ultimately, via respiration in aerobic soils, all the reduced C, N, P, and S materials are released as their oxidized forms, and oxygen is reduced to water to complete the cycle. Ideally, the cycle is conservative, particularly from the standpoint of nonleakage of nutrients, such as nitrate, into the groundwater. Similarly, contaminants entering the vadose zone, either as a function of agronomic use or by accident, should ideally be integrated into the natural nutrient cycles and converted to harmless by-products for assimilation and dissimilation by soil organisms and higher plants (Liu, 1994). Management of nutrient and contaminant transformations by the soil organisms requires a thorough understanding of the ecophysiological and solute transport ground rules that control the nature and rates of transformation options available to the soil organisms. In models of chemical transport and transformation through the vadose zone, colonies of microorganisms are frequently treated as a homogeneous biofilm reactor (Grant and Rochette, 1994). Often, modeling efforts are focused on environmental conditions external to the microbial colony. This consideration of the colony as a biofilm with relatively constant nutrient uptake rates ignores the growth differentiation that occurs as the colony develops
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Kumar, Sunil, Ranjit Kumar e Pankaj Sood. "Role of Microbial Enriched Vermicompost in Plant-Parasitic Nematode Management". In Nematodes - Recent Advances, Management and New Perspectives [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.97934.
Testo completoAbstract (sommario):
Earthworm causes increase in availability of soil organic matter through degradation of dead matters by microbes, leaf litter and porocity of soil. Vermicompost is a non-thermophilic biodegradation process of waste organic material through the action of microorganism with earthworm. Vermicompost is rich in many nutrients including calcium, nitrates, phosphorus and soluble potassium, which are essentially required for plant growth. Different plant growth hormones like gibberellins, auxins and cytokinins are present in vermicompost, which has microbial origin. Nematodes are mostly small, colorless and microscopic organisms which remain under soil, fresh or marine water, plants or animals, and act as parasite in different conditions, while very few have direct effect on human. The nematodes which are parasitic on plants use plant tissues as their food. They have well developed spearing device, like a hypodermic needle called stylet. It is used to penetrate host cell membrane. Management of plant-parasitic-nematodes therefore is necessary and several means are adopted. Of which, use of bio-chemicals and organic compost have shown encouraging results and proved to be potential in suppressing the nematode population. Vermicompost plays an important role of soil fortification on growth characteristics, such as length, weight, root, shoot branches, number of leaves and metabolism of host plant against nematode infection. Vermicompost fortified plants showed increment in sugar, protein and lipid over untreated control. Increment of these metabolites helps treated plants to metabolically cope up the infection and promotes excessive plant growth. The vermicompost caused the mortality of nematodes by the release of nematicidal substances such as hydrogen sulfate, ammonia, and nitrite apart from promotion of the growth of nematode predatory fungi that attack their cysts. It favours rhizobacteria which produce toxic enzymes and toxins; or indirectly favors population of nematophagous microorganisms, bacteria, and fungi, which serve as food for predatory or omnivorous nematodes, or arthropods such as mites, which are selectively opposed to plant-parasitic nematodes.
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Weis, Judith S. "Controversies in Aquatic Sciences". In Controversies in Science and Technology. Oxford University Press, 2014. http://dx.doi.org/10.1093/oso/9780199383771.003.0023.
Testo completoAbstract (sommario):
The aquatic sciences have their share of scientific controversies. In some cases the controversy is the classic situation of economic benefit versus environmental protection; in other cases it involves “genuine” scientific debate over uncertainties of the science or debate over what management option is optimal. This chapter discusses two pollution cases that pit scientists from universities or government agencies against those supported by the industry responsible for the pollution. Additional controversies that are also discussed are a disagreement over management options for shoreline protection, and a scientific disagreement over uncertainties in data on fish populations, which is usually the reason for controversies over fisheries. Controversies over effects of pollution often focus on how much (what concentration) of a chemical is needed to produce a certain harmful effect. Chemical companies tend to argue that levels of a chemical found in the environment are too low to cause problems, while environmentalists typically contend that lower levels can be harmful. One chemical about which there is sometimes controversy is oil. In the case of oil spills, debate commonly centers on how long the effects of pollution last. Oil degrades over time, resulting in less oil in the environment. The critical issue here is: When does this degradation reach a point where spilled oil is no longer harmful? Oil is a complex combination of various hydrocarbons that generally floats on water, although some lighter-weight components (the water-soluble fraction) dissolve. Weathering is a process that takes place in the air and water, in which the lightweight components evaporate, thus leaving the heavier components (e.g., tar), which have traditionally been viewed as less toxic. When oil comes into shallow water and marshes, it can coat and smother resident communities. It can sink below the surface of beaches and marshes and remain there for many years. Oil in marsh sediments undergoes some microbial breakdown but very slowly. Effects of a small oil spill (190,000 gallons of number 2 fuel oil) in Falmouth, Massachusetts, in the late 1960s lasted for over a decade, according to Sanders et al. (1980).
Atti di convegni sul tema "Soluble microbial products"
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Hu Xi-quan. "Formation of soluble microbial products (SMP) in an anaerobic sludge system". In 2011 Second International Conference on Mechanic Automation and Control Engineering (MACE). IEEE, 2011. http://dx.doi.org/10.1109/mace.2011.5987412.
Testo completo
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Holakoo, Ladan, George Nakhla, Ernest Yanful e Amarjeet Bassi. "Effect of Soluble Microbial Products on Simultaneous Nitrification-Denitrification in MBRs". In World Environmental and Water Resources Congress 2007. Reston, VA: American Society of Civil Engineers, 2007. http://dx.doi.org/10.1061/40927(243)271.
Testo completo
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Yang, Qi-Yong, Wei-ping Zhang e Xin-hua Zhang. "Performance of Soluble microbial products in hybrid membrane bioreactor with suspended carriers". In 2011 International Conference on Remote Sensing, Environment and Transportation Engineering (RSETE). IEEE, 2011. http://dx.doi.org/10.1109/rsete.2011.5965968.
Testo completo
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Garcia, Alfonso, Trevor Place, Michael Holm, Jennifer Sargent e Andrew Oliver. "Pipeline Sludge Sampling for Assessing Internal Corrosion Threat". In 2014 10th International Pipeline Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/ipc2014-33113.
Testo completoAbstract (sommario):
Internal corrosion sometimes occurs under deposits of solid particles on the bottom of transmission pipelines. The solids trap water with soluble products and other nutrients which can support the development of microbial communities and may lead to Microbiologically Influenced Corrosion (MIC). Corrosion processes associated with the metabolic activities of specific bacteria have been discussed elsewhere, but the simple presence of large microbial populations may increase the risk of internal corrosion owing to the ability of biofilms to extract and concentrate water at the pipe floor. As a method to monitor the internal corrosion threat in transmission pipelines and recommend mitigating activities for corrosion management, reliable microbial content and corrosion activity correlations are desired. Sludge samples have been obtained from cleaning pigs at the pipe trap and analyzed using Biological Activity Reaction Test (BART™) (or serial dilution test), Dean-Stark analysis, XRD and EDX. These tests provide information about certain bacterial populations, water / solid / hydrocarbon content, and crystalline/elemental composition of these solids, respectively. Despite best efforts, bacterial population/activity of pipeline sludge samples exhibit high variability and are difficult to correlate to actual internal corrosion in a pipeline. Considering that bacterial populations in pipeline sludge may be a meaningful representation of the internal corrosion threat to a transmission pipeline, a more rigorous approach on the sludge sampling procedure is necessary to improve the accuracy and reliability of the bacterial assays. It is also important to control such variables as storage temperature of the samples, exposure to air, and storage duration prior to enumeration — as these may affect the viability of the sample and enumeration results. This report presents historical pipeline sludge analysis data and suggests a method to evaluate data containing high variability. Practical recommendations to reduce data variability through handling and storage of sludge samples are also discussed.
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Barber, Steven T., Josh M. Dranoff e Thomas A. Trabold. "Initial Assessment of Microbial Fuel Cells for the Treatment of Tofu Processing Waste". In ASME 2015 9th International Conference on Energy Sustainability collocated with the ASME 2015 Power Conference, the ASME 2015 13th International Conference on Fuel Cell Science, Engineering and Technology, and the ASME 2015 Nuclear Forum. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/es2015-49558.
Testo completoAbstract (sommario):
Due to ever increasing industrial organic material wastewater regulations, there is growing interest in the food production industry for technologies to mitigate soluble waste discharges. Currently, food manufacturers in NYS with wastewaters that have high concentrations of soluble organic material, indicated by its chemical oxygen demand (COD), are charged substantial premiums by publicly owned treatment works (POTWs) to dispose of their high COD wastewaters. As a result, these producers are keen on pursuing more economical and sustainable alternatives. One novel option is a microbial fuel cell (MFC), a recently developed type of bioreactor that greatly reduces soluble COD by harnessing the electrochemical potential found in the chemical bonds of these organic materials through redox reactions under anaerobic conditions facilitated by exoelectrogenic microorganisms. MFC technology treating homogeneous substrates such as acetate at the laboratory scale has advanced to the point where COD removal efficiencies of over 90% are commonly achieved; however, efficiencies at treating less uniform, high COD level industrial scale food manufacturing wastewaters have only been investigated in a handful of studies. Since most real world wastewaters are non-uniform, MFC performance characterization of treating these actual discharges is crucial in determining their efficacy and cost effectiveness in large scale applications. To help fill this gap, this paper gives a relative efficacy comparison of five identical 3 L bench scale single chamber and three dual chamber MFC configurations (SCMFCs and DCMFCs, respectively) to a simulated POTW aeration process treating high COD whey effluent from a tofu manufacturing plant. Standard parametric EPA water quality tests of COD reduction were performed to assess the extent of the MFCs and POTW simulant effectiveness. COD levels in the MFC’s were reduced between 72% and 92%, while the POTW aeration process reduced levels 98%. This corroborates previously published studies showing that POTW systems are effective in reducing COD, but also that MFCs could be a more sustainable option due to their unique ability to directly produce, rather than consume, electric current. While these findings are promising, more studies are required to accurately determine the relative proportion of bioelectrochemical and methanogenic processes in the actual lowering of the COD levels.