Journal articles: 'Natural gas derivatives book'

1

Kwon, Sang Jang, and Soo Jong Kwak. "Optimal Hedging Strategy with Natural Ga Futures and Options." Journal of Derivatives and Quantitative Studies 10, no. 1 (May 31, 2002): 29–53. http://dx.doi.org/10.1108/jdqs-01-2002-b0002.

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In this paper, we theoretically examine the optimal hedge strategy for a natural gas company. The use of natural gas derivatives to minimize consumers' per unit cost of natural gas consumed, or to minimize the upside risk associated with extreme bills would be the strategy being considered by local distribution companies (LDCs) and regulators. The objective is, therefore, to stabilize the summer and the winter months' natural gas prices as well as to improve the level of customers' welfare. In general, during the summer injection period, April through October, utility companies purchase a certain amount of natural gas and keep in storage facilities and, hence, during the winter withdrawal months, November through March, utility companies supply natural gas at a predetermined minimal fuel cost rate to residential and commercial customers. Therefore, to manage these conflicts of interests efficiently should natural gas companies be supported by accurate forecast of the natural gas price for the winter months. Otherwise, natural gas companies will trade natural gas derivatives in order to reduce costs charged to customers. The results show that customers benefit from the use of natural gas derivatives. If the natural gas market is deregulated, the typical risk-return trade off shows that natural gas derivatives would provide the most efficient tools for utility companies to minimize the natural gas price volatilities.

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2

Sweet, Colin. "Book Review: The Political Economy of Natural Gas." Journal of Interdisciplinary Economics 2, no. 4 (April 1988): 336–37. http://dx.doi.org/10.1177/02601079x8800200409.

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3

Zhang, Gengwu, Bin Hua, Avishek Dey, Munmun Ghosh, Basem A. Moosa, and Niveen M. Khashab. "Intrinsically Porous Molecular Materials (IPMs) for Natural Gas and Benzene Derivatives Separations." Accounts of Chemical Research 54, no. 1 (December 17, 2020): 155–68. http://dx.doi.org/10.1021/acs.accounts.0c00582.

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4

Schwark, Bastian. "Book Review: The Economics of Natural Gas Storage: A European Perspective." Competition and Regulation in Network Industries 10, no. 4 (December 2009): 413–15. http://dx.doi.org/10.1177/178359170901000406.

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Khadzhiev, S. N., N. V. Kolesnichenko, and N. N. Ezhova. "Manufacturing of lower olefins from natural gas through methanol and its derivatives (review)." Petroleum Chemistry 48, no. 5 (September 2008): 325–34. http://dx.doi.org/10.1134/s0965544108050010.

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6

Chizhov, Alexander O., Yury E. Tsvetkov, and Nikolay E. Nifantiev. "Gas-Phase Fragmentation of Cyclic Oligosaccharides in Tandem Mass Spectrometry." Molecules 24, no. 12 (June 14, 2019): 2226. http://dx.doi.org/10.3390/molecules24122226.

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Modern mass spectrometry, including electrospray and MALDI, is applied for analysis and structure elucidation of carbohydrates. Cyclic oligosaccharides isolated from different sources (bacteria and plants) have been known for decades and some of them (cyclodextrins and their derivatives) are widely used in drug design, as food additives, in the construction of nanomaterials, etc. The peculiarities of the first- and second-order mass spectra of cyclic oligosaccharides (natural, synthetic and their derivatives and modifications: cyclodextrins, cycloglucans, cyclofructans, cyclooligoglucosamines, etc.) are discussed in this minireview.

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Wang, Yanfei, Yaxin Ning, and Yibo Wang. "Fractional Time Derivative Seismic Wave Equation Modeling for Natural Gas Hydrate." Energies 13, no. 22 (November 12, 2020): 5901. http://dx.doi.org/10.3390/en13225901.

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Simulation of the seismic wave propagation in natural gas hydrate (NGH) is of great importance. To finely portray the propagation of seismic wave in NGH, attenuation properties of the earth’s medium which causes reduced amplitude and dispersion need to be considered. The traditional viscoacoustic wave equations described by integer-order derivatives can only nearly describe the seismic attenuation. Differently, the fractional time derivative seismic wave-equation, which was rigorously derived from the Kjartansson’s constant-Q model, could be used to accurately describe the attenuation behavior in realistic media. We propose a new fractional finite-difference method, which is more accurate and faster with the short memory length. Numerical experiments are performed to show the feasibility of the proposed simulation scheme for NGH, which will be useful for next stage of seismic imaging of NGH.

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8

Correljé, Aad. "Book Review: Security of Energy Supply in Europe: Natural Gas, Nuclear and Hydrogen." Competition and Regulation in Network Industries 12, no. 3 (September 2011): 287–89. http://dx.doi.org/10.1177/178359171101200305.

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9

Łęt, Blanka. "LINKAGES OF NATURAL GAS AND OIL FUTURES PRICES ON THE AMERICAN AND EUROPEAN DERIVATIVES MARKET." Prace Naukowe Uniwersytetu Ekonomicznego we Wrocławiu, no. 482 (2017): 158–68. http://dx.doi.org/10.15611/pn.2017.482.13.

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10

Ewald, Christian-Oliver, Roy Nawar, and Tak Kuen Siu. "Minimal variance hedging of natural gas derivatives in exponential Lévy models: Theory and empirical performance." Energy Economics 36 (March 2013): 97–107. http://dx.doi.org/10.1016/j.eneco.2012.12.004.

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11

Igor Leonidovich, Beilin. "Innovation Management in the Supply Chains of Russian Natural Gas, Taking into Account the Regional Structure of its Production." Nexo Revista Científica 33, no. 02 (December 31, 2020): 579–89. http://dx.doi.org/10.5377/nexo.v33i02.10793.

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The article describes the role of Russia in the global gas industry, on the basis of the analysis of the factual data cited, conclusions are drawn about the provision of the economy with the considered minerals, the main problems in managing the supply chains of natural gas and liquefied natural gas are formulated, and innovative ways to solve them are proposed. Based on the fuzzy modeling method, it was shown that the maximum amount of budget revenues from the export duty of Russian natural gas from the main gas-bearing regions can almost double. At the same time, the minimum volume in the same case remains virtually unchanged, remaining within 10%. The use of fuzzy modeling in innovation management in the supply chains of Russian natural gas is caused by high volatility in the global commodity markets, both for the underlying asset (in this case, natural gas) and for derivative financial instruments (derivatives). Based on the simplex optimization method, innovation management schemes have been developed in the supply chains of Russian natural gas, taking into account the regional structure of its production. The differences in the economic efficiency of the export duty for the Russian budget between the supply of pipeline natural gas and liquefied natural gas are shown. The author’s methods presented in the article can be used as additional innovative tools for making strategic and operational management decisions by industry leaders and public authorities.

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Vosmerikov, A. V., L. N. Vosmerikova, G. V. Echevsky, L. L. Korobitsyna, Ye G. Kodenev, and L. M. Velichkina. "Generation of Liquid Products from Natural Gas over Zeolite Catalysts." Eurasian Chemico-Technological Journal 5, no. 4 (April 6, 2016): 271. http://dx.doi.org/10.18321/ectj314.

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The main component of the natural gas is methane, whose molecules are characterized by a high chemical and thermal stability. It is impossible to perform the chemical transformation of natural gas into liquid organic compounds without applying highly active polyfunctional catalysts. Natural gas might be converted into liquid products in the presence of zeolite catalysts of pentasil family. Zeolite catalysts of ZSM-5 type were prepared to realize the process. They contained various amounts of Zn and Ga promoters introduced by ion exchange and impregnation. It has been shown that in the presence of small amounts of C2-C5 alkanes in the feedstock the methane is converted into aromatic hydrocarbons much more readily and in softer conditions than pure methane. At optimum process conditions reached is a high conversion of the natural gas into a mixture of aromatic hydrocarbons. This mixture mainly consists of benzene and naphthalene and small amounts of their derivatives – toluene, C8 and C9+ alkylbenzenes, methyl- and dimethylnaphthalenes. An optimum composition of zeolite matrix and the amount of the modifier in the catalyst have been established.

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Bai, Dongjie, Yao Wang, Minghui He, Xiaoxia Gao, and Yabing He. "Structural diversities and gas adsorption properties of a family of rod-packing lanthanide–organic frameworks based on cyclotriphosphazene-functionalized hexacarboxylate derivatives." Inorganic Chemistry Frontiers 5, no. 9 (2018): 2227–37. http://dx.doi.org/10.1039/c8qi00575c.

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A family of Ln-MOFs constructed from flexible hexacarboxylate derivatives exhibit substituent-driven structural diversity, and the methoxy-modified one displays the potential for natural gas purification.

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14

HINZ, JURI, and MARTINA WILHELM. "PRICING FLOW COMMODITY DERIVATIVES USING FIXED INCOME MARKET TECHNIQUES." International Journal of Theoretical and Applied Finance 09, no. 08 (December 2006): 1299–321. http://dx.doi.org/10.1142/s0219024906004001.

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In this work, the valuation of energy-related financial contracts written on prices of flow commodities (such as natural gas, oil and electrical power) will be elaborated. Due to restrictions on storability of the underlying, the pricing of flow commodity derivatives is not trivial and thus correct valuation is still under discussion. In this paper, an axiomatic setting is followed, which provides a connection to interest rate theory, whose toolkit we utilize to consistently price frequently quoted flow commodity options such as caps, floors, collars and cross commodity spreads.

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15

Ohirhian, P. U., and I. N. Abu. "A New Correlation for the Viscosity of Natural Gas." Advanced Materials Research 62-64 (February 2009): 474–83. http://dx.doi.org/10.4028/www.scientific.net/amr.62-64.474.

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A new equation for the viscosity of Natural Gas under Reservoir conditions has been developed. The equation was obtained by the analysis of experimental Pressure, Volume and Temperature (PVT) Data of Gas associated with Nigerian Crude Oil. The PVT Data were those of renowned companies that operate in Nigeria. The pressure ranged from 144 psia to 4100 psia, and a temperature variation between 130oF and 220oF. Comparison of the equation formulated in this work with experimental PVT viscosity gave an average absolute error of 1.55%, a maximum absolute error of 4.878% and a standard deviation of 1.29. A comparison of viscosity obtained from the charts of Carr et al and the equation of Lee et al with Nigerian PVT Viscosity showed that the new equation gave more accurate result. Since some Correlations perform better when applied to data from which they were derived, a further comparison test was performed. In this test, the new equation was used to solve two problems for which solutions by the method of Carr et al were available. The first problem from the Handbook of Natural Gas Engineering by Katz et al gave a viscosity of 1.158cp while the new equation gave 1.157cp. The second problem from Ikoku’s book (Natural Gas Production Engineering) gave a viscosity of 1.178cp and the new equation also gave 1.178cp. This closeness of the viscosity of the new equation to the values from the Carr et al method proved the applicability of the new equation to any type of Natural Gas.

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16

Kelly, Cameron. "Book review: Agricultural Land Use and Natural Gas Extraction Conflicts: A Global Socio-Legal Perspective." Environmental Law Review 22, no. 1 (March 2020): 75–77. http://dx.doi.org/10.1177/1461452920915974.

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17

McDevitt, Lisa. "Book Review: Review of Fracking the Neighborhood: Reluctant Activists and Natural Gas Drilling." International Journal of Mass Emergencies & Disasters 37, no. 3 (November 2019): 332–35. http://dx.doi.org/10.1177/028072701903700306.

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18

Slynko, N. M., N. V. Burmakina, O. M. Potseluyev, S. Yu Kapustyanchik, G. Yu Galitsin, T. N. Goryachkovskaya, L. V. Kuybida, S. V. Shekhovtsov, S. E. Peltek, and V. K. Shumny. "Gas chromatography-mass spectrometry in the taxonomy of Miscanthus." Vavilov Journal of Genetics and Breeding 23, no. 8 (January 10, 2020): 1076–81. http://dx.doi.org/10.18699/vj19.583.

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Chemotaxonomy as a system approach deals with intra- and interspecific polymorphism of a group of taxa in order to clarify their taxonomic positions or to select material for selection or introduction. In this study we performed chemotaxonomic analysis of specimens of Miscanthus sinensis and M. sacchariflorus collected in the Russian Far East and of hybrid plants of both natural and artificial origin. We found 153 substances and identified 143 of them in extracts of eleven Miscanthus plants by gas chromatography-mass spectrometry (GC-MS). These substances can be grouped into alkanes (20 compounds), fatty acids (34), phenols (13), sterols (18) toсopherols (8), norterpenoids (12), and phytols (13), as well as their derivatives. The main components of the extracts of miscanthus samples are fatty acids and their derivatives (total content 19.94–41.02 %), dominated by palmitic and linolenic acids, and sterols (mainly β-sitosterol, stigmasterol, and α-amyrin), which constitute 17.15–31.73 %. The values of the CPI “oddness index” for the alkane components of the extracts were within 1.55–7.18, with extracts from leaves of the Far Eastern samples characterized by the lower half of this range (1.55–2.74), while extracts from leaves of hybrids fell to the upper half (5.78–7.18). Principal component analysis of extraction profiles allowed us to separate three distinct clusters: M. sinensis, M. sachariflorus, and their hybrids, as well as to verify the origin of one of the natural hybrids. The results of chemotaxonomic analysis mostly matched those of DNA sequencing of a fragment of the plastid genome, which, moreover, allowed us to identify the species nature of the maternal plants used to obtain these hybrids. Chemotaxonomic analysis using GC-MS was found to be an efficient additional technique to delimit various morphological forms of M. sinensis, M. sachariflorus, and their hybrids.

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19

Gaganis, Vassilis, Dirar Homouz, Maher Maalouf, Naji Khoury, and Kyriaki Polychronopoulou. "An Efficient Method to Predict Compressibility Factor of Natural Gas Streams." Energies 12, no. 13 (July 4, 2019): 2577. http://dx.doi.org/10.3390/en12132577.

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The gas compressibility factor, also known as the deviation or Z-factor, is one of the most important parameters in the petroleum and chemical industries involving natural gas, as it is directly related to the density of a gas stream, hence its flow rate and isothermal compressibility. Obtaining accurate values of the Z-factor for gas mixtures of hydrocarbons is challenging due to the fact that natural gas is a multicomponent, non-ideal system. Traditionally, the process of estimating the Z-factor involved simple empirical correlations, which often yielded weak results either due to their limited accuracy or due to calculation convergence difficulties. The purpose of this study is to apply a hybrid modeling technique that combines the kernel ridge regression method, in the form of the recently developed Truncated Regularized Kernel Ridge Regression (TR-KRR) algorithm, in conjunction with a simple linear-quadratic interpolation scheme to estimate the Z-factor. The model is developed using a dataset consisting of 5616 data points taken directly from the Standing–Katz chart and validated using the ten-fold cross-validation technique. Results demonstrate an average absolute relative prediction error of 0.04%, whereas the maximum absolute and relative error at near critical conditions are less than 0.01 and 2%, respectively. Most importantly, the obtained results indicate smooth, physically sound predictions of gas compressibility. The developed model can be utilized for the direct calculation of the Z-factor of any hydrocarbon mixture, even in the presence of impurities, such as N 2 , CO 2 , and H 2 S, at a pressure and temperature range that fully covers all upstream operations and most of the downstream ones. The model accuracy combined with the guaranteed continuity of the Z-factor derivatives with respect to pressure and temperature renders it as the perfect tool to predict gas density in all petroleum engineering applications. Such applications include, but are not limited to, hydrocarbon reserves estimation, oil and gas reservoir modeling, fluid flow in the wellbore, the pipeline system, and the surface processing equipment.

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20

Mueller, S. F., Q. Mao, and J. W. Mallard. "Modeling natural emissions in the Community Multiscale Air Quality (CMAQ) model – Part 2: Modifications for simulating natural emissions." Atmospheric Chemistry and Physics Discussions 10, no. 6 (June 28, 2010): 15811–84. http://dx.doi.org/10.5194/acpd-10-15811-2010.

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Abstract. A recent version (4.6) of the Community Multiscale Air Quality (CMAQ) model was used as the basis for testing model revisions for including reactions involving chlorine (HCl, ClNO2) and reduced sulfur (dimethylsulfide, or DMS, and H2S) species not normally treated in the CB05 gas chemical mechanism and cloud chemistry module. Model chemistry revisions were based on published reaction kinetic data and a recent cloud chemistry model that includes heterogeneous reactions of organic sulfur compounds. Testing of the revised model was conducted using a recently enhanced data base of natural emissions that includes ocean and continental sources of DMS, H2S, chlorinated gases and lightning NOx for the continental United States and surrounding regions. Results using 2002 meteorology and emissions indicated that most simulated chemical and aerosol species exhibit the expected seasonal variations in grid-average surface concentrations. Ozone exhibits a winter and early spring maximum – reasonably consistent with ozone data and model results produced by others – in a pattern that reflects the influences of atmospheric dynamics and pollutant background levels imposed on the CMAQ simulation by boundary conditions derived from a global model. A series of experimental model simulations reveals that the addition of gas phase organic sulfur chemistry leads to sulfate aerosol increases over most of the continental United States. Modifications to the cloud chemistry module result in widespread decreases in SO2 across the modeling domain and a mix of sulfate increases and decreases. Most cloud-mediated sulfate increases occurred over the Pacific Ocean (up to about 0.1 μg m-3) and at slightly lesser amounts over and downwind from the Gulf of Mexico (including portions of the Eastern US). Variations in the chemical response are due to the link between DMS/H2S and their byproduct SO2, the heterogeneity of cloud cover and precipitation (precipitating clouds act as net sinks for SO2 and sulfate), and the persistence of cloud cover (the largest relative sulfate increases occurred over the persistently cloudy Gulf of Mexico and western Atlantic Ocean). Overall, the addition of organic sulfur chemistry increased surface hourly sulfate levels by as much as 1–2 μg m-3 in selected grid cells. The added chemistry produced significantly less sulfate in the vicinity of high SO2 emissions (e.g., wildfires), perhaps in response to lower OH from competing reactions with DMS and its derivatives. Simulated surface levels of DMS compare favorably with published observations made in the marine boundary layer. However, DMS derivatives are lower than observed implying either less chemical reactivity in the model or a low bias in the boundary conditions for DMS derivatives such as dimethylsulfoxide. The sensitivity of sulfate to cloud cover and the aqueous sulfate radical is also explored. This revised version of CMAQ provides a tool for more realistically evaluating the influence of natural emissions on air quality.

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21

Hafner, Manfred, Simone Tagliapietra, and Sergio Matalucci. "Book review: The Globalization of Natural Gas MarketsNew Challenges and Opportunities for Europe." European Energy & Climate Journal 4, no. 2 (April 1, 2014): 11–12. http://dx.doi.org/10.4337/eecj.2014.02.03.

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22

Froissard, Didier, Sylvie Rapior, Jean-Marie Bessière, Alain Fruchier, Bruno Buatois, and Françoise Fons. "Volatile Organic Compounds of six French Dryopteris Species: Natural Odorous and Bioactive Resources." Natural Product Communications 9, no. 1 (January 2014): 1934578X1400900. http://dx.doi.org/10.1177/1934578x1400900138.

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Aerial parts of six Dryopteris species collected in France were investigated for volatile organic compounds (VOC) for the first time. Fifty-three biosynthesized VOC from the shikimic, lipidic and terpenic pathways were identified using gas chromatography/mass spectrometry. Many bioactive polyketide compounds as filicinic derivatives (from 8.5 to 23.5%) and phloroglucinol derivatives (from 8.2 to 53.8%) with various pharmacological activities were detected in high amount from five analysed Dryopteris species, in particular D. oreades and D. borreri, i.e., propionylfilicinic acid (> 10% in D. affinis and D. ardechensis) and 2,6-dihydroxy-4-methoxy-3-methylbutyrophenone (aspidinol) (19.1% and 14.6% in D. oreades and D. borreri, respectively). Several terpenic derivatives with a low odor threshold were identified, i.e., carota-5,8-diene (from 2.5 to 18.4%: floral, woody or fresh bark note), ( E)-nerolidol (> 10% for D. borreri and D. cambrensis; floral or woody odor), α-selinene (> 7% for D. ardechensis; woody-spicy odor), and aristolene (12.8% in D. affinis; flower, sweet odor). The main isoprenoid derivatives were 4-hydroxy-5,6-epoxyionol, 3-oxo-α-ionol and 4-oxo-7,8-dihydro-β-ionone (essentially in D. remota), whereas the main aromatic compound was 4-hydroxy-3-methoxyacetophenone (20.6% and 12.6% in D. cambrensis and D. borreri, respectively) and the main lipid derivative was 1-octen-3-ol with a mushroom-like odor (from 0.4 to 8.3%). Dryopteris species resources are of great interest as a reservoir of odorous and bioactive compounds.

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23

Jerković, Igor, Marina Kranjac, Marina Zekić, Ani Radonić, and Zvonimir Marijanović. "The Application of Headspace Solid-phase Microextraction as a Preparation Approach for Gas Chromatography with Mass Spectrometry." Kemija u industriji 69, no. 9-10 (2020): 515–20. http://dx.doi.org/10.15255/kui.2020.020.

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Reviewed in brief are the selected results of the application of headspace solid-phase microextraction as a preparative approach for gas chromatography – mass spectrometry (HS-SPME/GC-MS) for natural organic compounds research at the University of Split, Faculty of Chemistry and Technology. A wide variety of headspace compounds from different natural sources has been identified: lower aliphatic compounds (e.g., C5- and C6-compounds), aromatic compounds, monoterpenes (e.g., linalool derivatives (oxides, anhydro-oxides, epoxides), hotrienol), sesquiterpenes (e.g., eudesmol isomers, hydrocarbons), and C9- and C13-norisoprenoids (e.g., 3,4-dihydro-3-oxoedulan, 4-oxoisophorone, trans-β-damascenone). These compounds are important phytochemicals as flavour/fragrance compounds, chemical markers of the botanical origin or others (e.g., allelochemicals, pheromones, or acaricide residue).

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Korniievskyi, Yu I., O. I. Panasenko, V. H. Korniievska, B. O. Varynskyi, and M. M. Maletskyi. "Natural aspirin of some members of the Rosaceae and Salicaceae families." Current issues in pharmacy and medicine: science and practice 15, no. 2 (August 1, 2022): 153–59. http://dx.doi.org/10.14739/2409-2932.2022.2.256639.

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White willow Salix alba L., a member of the family Salicaceae is characterized by the presence of phenolic compounds and their glycosides (1.5–11.0 %), such as salicin, salicortin, salireposide, picein, triandrin, syringin, tremulacin, flavonoids (1–4 %) namely luteolin, apigenin, quercetin, quercimeritrin, cosmosin, diosmetin, tannins (8–20 %) i.e. catechins, anthocyanidins, halotanines of organic acids, ascorbic acid. Preparations of white willow bark are used as an antipyretic, anti-inflammatory, diaphoretic, analgesic, diuretic, and astringent. The rhizomes with roots of the commonly known dropwort or fern-leaf dropwort are Filipendula vulgaris Moench., member of the family Rosaceae are characterized by phenologicoside gaulterin, the hydrolysis of which produces salicylic aldehyde, tannins (up to 33 %), flavonoids, ascorbic acid, polysaccharides, starch. The herbs and flowers are used as anti-inflammatory, anti-rheumatic, vasodilator, gastric, and antiulcer agents. The aim of the work is to determine the composition of the white willow bark Salix alba L. tincture, a member of the willow family Salicaceae, using gas-liquid chromatography (GLC) and HPLC and to determine the composition of the tincture of the dropwort root Filipendula vulgaris Moench. family Rosaceae. Materials and methods. Raw materials (underground organs) of the dropwort Filipendula vulgaris Moench. and bark of the white willow Salix alba L., which were harvested in July 2020 at the ZSMU research site. Tinctures were prepared according to the production recipe (1:5) (extractant was 70 % ethanol), investigated by the gas chromatograph Agilent 7890B with mass spectrometric detector 5977B. The mass spectra library NIST 14 was used to identify the components. White willow bark tincture (70 % ethyl alcohol extractant) was used to determine the phenolic compounds content and salicylic acid derivatives. The study was performed by HPLC (high-performance liquid chromatography) and HPLC MS. Results. Qualitative and quantitative analysis of the components of Salix alba L. willow bark tincture was performed by gas-liquid chromatography, 39 components of different classes of biologically active compounds have been identified, among which the 10 components are predominated in quantitative content. The main one was Salicin (39.53 %). The GC analysis of the tincture of the dropwort roots, Filipendula vulgaris Moench., identified 34 components of different groups of biologically active compounds, dominated by 11 components, the main is Ethyl.alpha.-d-glucopyranoside (34.55 %). HPLC analysis confirmed the presence of phenolic compounds (flavonoids such as apigenin, and quercetin) and salicylic acid derivatives (glycoside salicin) in the tincture of white willow bark (Salix alba L.). Conclusions. By GC analysis the 39 components in tincture of white willow bark Salix alba L. were identified, 10 components were predominated, the main one was Salicin (39.53 %). The 34 components in the tincture of the dropwort roots, Filipendula vulgaris Moench., were identified, dominated by 11 components, the main was Ethyl.alpha.-d-glucopyranoside (34.55 %). The presence of phenolic compounds (flavonoids were apigenin and quercetin) and salicylic acid derivatives (glycoside salicin) was confirmed by HPLC MS in the tincture of white willow bark (Salix alba L.).

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Curtin, J. Sean. "Book Review: China and the Global Energy Crisis – Development and Prospects for China’s Oil and Natural Gas." Journal of Interdisciplinary Economics 19, no. 2-3 (January 2008): 303–5. http://dx.doi.org/10.1177/02601079x08001900210.

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Jefferson, A., MV Sargent, and S. Wangchareontrakul. "Synthesis and Identification of ω-Phenylalkylcatechols in Burmese Lac." Australian Journal of Chemistry 41, no. 1 (1988): 19. http://dx.doi.org/10.1071/ch9880019.

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The presence of 3-(10′-phenyldecyl)-(2) (2%), 3-(12′-phenyldodecyl)- (3) (6%), 4-(10′-phenyldecyl)-(4) (0.3%) and 4-(12′-phenyldodecyl)- benzene-1,2-diol (5) (0.3%) in Burmese lac , the sap of Melanorrhoea usitata Wall has been confirmed by the synthesis of these compounds and a comparison of the gas chromatographic retention times and the mass spectral characteristics of their bis-O-( trimethylsilyl ) derivatives with the derivatives of the natural products. Typically, 3,4- bis ( benzyloxy ) benzaldehyde (7) on Wittig reaction with triphenyl (11- phenylundecyl ) phosphonium bromide (20) and subsequent catalytic hydrogenation of the resultant olefin gave compound (5) in 59% overall yield.

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Director, L. B., K. A. Homkin, I. L. Maikov, Yu L. Shekhter, G. F. Sokol, and V. M. Zaichenko. "Theoretical and Experimental Investigations of Substantiating Technologies for Carbon Materials Production from Natural Gas." Eurasian Chemico-Technological Journal 5, no. 1 (July 12, 2017): 29. http://dx.doi.org/10.18321/ectj587.

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The results of theoretical and experimental investigations on methane pyrolysis with infiltration through a heated porous matrix generated from various carbon materials are presented. The features of mathematical models, kinetic relationships of process are discussed. The mathematical model of process shares on external problem (a flow of particles in an external stream) and internal problem (reaction in particle porous). The heat and mass transfer for the average (over the reactor cross section) parameters, ignoring the heat transfer in gas by thermal conductivity, is described by unsteady-state one-dimensional differential equations in partial derivatives. For the mathematical description of process kinetics of methane decomposition the approach is used by which the soot formation is treated as a chain radical process. The porous media is represented by a system of large enough particles. In its turn, every macroparticle consists of finer particles, which are also composed of microparticles, etc. Calculating programs were used for modeling and efficiency analysis of technological installations for technical carbon production in a regenerative heater, filled by a ceramic nozzle and for similar purposes concerning carbon (oven soot) in autothermal torch process of partial gas oxidation by air at a surplus factor of oxidizer in relation to stoichiometry 0.4-0.5 at pressure close to atmospheric on Sosnogorsk Gas-Processing Plant. Experiment descriptions and techniques for experimental realization are given. These results are used as fundamentals for new technologies considering pyrocarbon materials production in the continuous operation reactor.

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Ведерников, Д. Н., and Е. А. Рысева. "Synthesis of esters of birch bud sesquiterpene alcohols and cinnamic acid derivatives." Известия СПбЛТА, no. 238 (March 11, 2022): 160–69. http://dx.doi.org/10.21266/2079-4304.2022.238.160-169.

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Данное исследование направлено на создание лекарственных препаратов, подавляющих рост микроорганизма Staphylococcus epidermidis, вызывающего заболевания, сложно поддающихся лечению. В работе продемонстрирована удачная попытка синтеза природных сложных эфиров – кумаратов сесквитерпеновых спиртов из сесквитерпеновых соединений почек березы. Хроматографические и масс-спектрометрические характеристики полученных соединений совпали с характеристиками природных. Синтез включал: получение экстракта почек, омыление ацетатов сесквитерпеновых спиртов, вакуумную дистилляцию фракции сесквитерпеновых спиртов, получение ацетата кумаровой кислоты, оксалилхлорида, хлорангидрида ацетата кумаровой кислоты, сложных эфиров ацетата кумаровой кислоты и сесквитерпеновых спиртов, гидролиз ацетильной группы, очистку продуктов гидролиза хроматографией на силикагеле. Выход продуктов в расчете на сесквитерпеновые спирты составил 70%. Контроль за качеством и количеством промежуточных и конечных продуктов осуществляли методом газовой хромато-масс-спектрометрии. Полученные синтетические соединения, как и природные, показали противомикробную активность в отношении Staphylococcus epidermidis с МПК = 1000 мкг/мл. Оценённая антимикробная активность была в 20 раз меньше активности природных кумаратов сесквитерпеновых спиртов. Состав полученных продуктов отличался от природных соединений отсутствием одного из главных компонентов – кумарата τ-бетуленола; τ-бетуленол обнаружен в почках березы только в виде спиртового остатка сложного эфира кумаровой кислоты. This research is aimed at creating drugs that inhibit the growth of the microorganism Staphylococcus epidermidis, which causes difficult to treat diseases. The study shows a successful attempt to synthesize natural esters – coumarates of sesquiterpene alcohols from sesquiterpene compounds of birch buds. The chromatographic and mass spectrometric characteristics of the obtained compounds coincide with the characteristics of natural ones. Control over the quality and quantity of intermediate and final products was carried out by gas chromatography-mass spectrometry. The resulting products showed retention times and mass spectra corresponding to natural values. The synthesis included the preparation of a vegetative buds extract, saponification of sesquiterpene alcohol acetate, vacuum distillation of the sesquiterpene alcohol fraction, preparation of coumaric acid acetate, oxalyl chloride, coumaric acid acetate chloride, esters of coumaric acid acetate and sesquiterpene acetyl alcohols, hydrolysis and chromatography of products with silica gel. The product yield, calculated as sesquiterpene alcohols, was 70%. The synthesized compounds, as well as natural ones, showed antimicrobial activity against Staphylococcus epidermidis with a MIC = 1000 μg / ml. The estimated antimicrobial activity was 20 times less than the activity of natural coumarates of sesquiterpene alcohols. The composition of the obtained products differed from natural compounds by the absence of one of the main components – τ-betulenol coumarate. τ-Betulenol is absent in free form in birch buds.

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Villmann, Thomas, and Sven Haase. "Divergence-Based Vector Quantization." Neural Computation 23, no. 5 (May 2011): 1343–92. http://dx.doi.org/10.1162/neco_a_00110.

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Supervised and unsupervised vector quantization methods for classification and clustering traditionally use dissimilarities, frequently taken as Euclidean distances. In this article, we investigate the applicability of divergences instead, focusing on online learning. We deduce the mathematical fundamentals for its utilization in gradient-based online vector quantization algorithms. It bears on the generalized derivatives of the divergences known as Fréchet derivatives in functional analysis, which reduces in finite-dimensional problems to partial derivatives in a natural way. We demonstrate the application of this methodology for widely applied supervised and unsupervised online vector quantization schemes, including self-organizing maps, neural gas, and learning vector quantization. Additionally, principles for hyperparameter optimization and relevance learning for parameterized divergences in the case of supervised vector quantization are given to achieve improved classification accuracy.

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Quintino, António, João Carlos Lourenço, and Margarida Catalão-Lopes. "An Integrated Risk Management Model for an Oil and Gas Company." International Journal of Economics and Statistics 10 (March 15, 2022): 80–87. http://dx.doi.org/10.46300/9103.2022.10.13.

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Oil and gas companies’ returns are heavily affected by price fluctuations. In financial terms, the “price in—price out” dynamics influence companies’ gross margins and impact to a high extent on their multiyear budgets and accomplishment of goals. Due to world scale size and geographically scattered organizations oil and gas companies use separate hedging tactics to protect each of their business units (e.g. crude oil production, oil refining and natural gas) from the risk associated with the fluctuation of prices. The present research compares, for an oil and gas company, the results of using a “hedging at business unit level” approach with the results of employing a “hedging at company level” approach, by finding the best derivatives portfolios through coherent risk measures and stochastic optimization. The analysis is subsequently extended to a utility based approach, where the company’s risk tolerance is included.

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Than, Tin Maung Maung. "BOOK REVIEW: Oil and Natural Gas Resources in the ESCAP Region: Geology, Reserves, Production, Potential, Distribution, by ESCAP." Southeast Asian Economies 6, no. 2 (1989): 216–17. http://dx.doi.org/10.1355/ae6-2m.

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32

Carral, Luis, Javier Tarrío-Saavedra, Diego Crespo-Pereira, Marina Fernández-Campoamor, and Rodolfo Sabonge. "Competitive position of the expanded Panama Canal in the shipment of liquefied natural gas." Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment 233, no. 4 (November 28, 2018): 1154–76. http://dx.doi.org/10.1177/1475090218812242.

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The appearance of new gas extraction technologies has led to surplus production in the United States (Gulf of Mexico). At the same time, energy consumption in Asia has increased significantly and Japan has introduced important changes to its post-Fukushima energy policies. Taken together, these factors have resulted in an imbalance in production and consumption between the Atlantic and Pacific Maritime Areas. Over the same period of time, the Panama Canal expansion opened, permitting transit by liquefied natural gas vessels for the first time. These developments are reflected in the current order book for liquefied natural gas carriers, which is composed entirely of ships in the new Neopanamax category. The canal transit fees and new propulsion systems for these ships—dual fuel diesel electric and electronically controlled gas injection—significantly impact the price of cargo at the destination. This study conducts a sensitivity analysis of the variables for transportation costs in order to determine the expanded Canal’s competitive position. In addition, the study uses a Monte Carlo simulation to obtain the most representative values for total cost based on factors such as the type of propulsion and fuel as well as the distance traveled. The analysis clearly demonstrates the competitiveness of exporting liquefied natural gas via the Panama Canal from terminals in the Gulf of Mexico and the Caribbean to consumers in Asia, as well as the competitiveness of the canal itself versus alternative routes. With respect to propulsion systems, the study demonstrates the greater competitive advantage of electronically controlled gas injection propulsion.

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Sellamuthu Prabakaran, Dr, and . "Modeling and Pricing of Energy Derivative Market." International Journal of Engineering & Technology 7, no. 4.10 (October 2, 2018): 148. http://dx.doi.org/10.14419/ijet.v7i4.10.20826.

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Energy derivatives are an energy instrument whose value be determined by on or derived from the values, more basic, a fundamental energy asset, such as crude oil, electricity, or natural gas. Energy derivatives are nonstandard products that have been generated by financial engineers (I. e exotic derivatives) and include exchange-traded contracts such as options and futures. In energy industries, the risk management and pricing model are important because the volatility of pricing in energy products. The price of the volatility can decrease the income of business strategies and its affects the consumer´s buying and selling decisions. For this reason, we have to manage the pricing risk and it became a pressure in the energy industries to continue the profitability and to avoid competitive disadvantages. The main goal of this study is to construct the option-pricing model for energy derivative markets.

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Ahlstrøm, Ø., A. H. Tauson, A. Frydendahl Hellwing, L. Mydland, and A. Skrede. "Growth performance, nitrogen balance and urinary purine derivatives in growing-furring mink (Mustela vison) fed bacterial protein produced from natural gas." Journal of Animal and Feed Sciences 15, no. 3 (July 5, 2006): 491–504. http://dx.doi.org/10.22358/jafs/66919/2006.

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Olsson, Nils U., Peter Kaufmann, and Susanna Dzeletović. "Preparation and gas chromatographic—mass spectrometric analysis of N-acetyl-O-trimethylsilyl derivatives of long-chain base residues of natural sphingomyelin." Journal of Chromatography B: Biomedical Sciences and Applications 698, no. 1-2 (September 1997): 1–8. http://dx.doi.org/10.1016/s0378-4347(97)00300-9.

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Afe Aidelojie, Kenneth E. "Book Review: Liquefied Natural Gas: The Law and Business of LNG, edited by Paul Griffin. (Second Edition, January 2012)." European Energy and Environmental Law Review 21, Issue 4 (August 1, 2012): 192–94. http://dx.doi.org/10.54648/eelr2012017.

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37

Fouegue, Aymard Didier Tamafo, Désiré Bikélé Mama, Julius Numbonui Ghogomu, Younang Elie, and Marie-Annie Etoh. "The Substitution Effect on Reaction Enthalpies of Antioxidant Mechanisms of Juglone and Its Derivatives in Gas and Solution Phase: DFT Study." Journal of Chemistry 2018 (2018): 1–10. http://dx.doi.org/10.1155/2018/1958047.

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We examined the structure-reaction enthalpies-antioxidant activity relationship of the molecule library built around juglone and its derivatives at B3LYP/6-31+G(d,p) level. Three major antioxidant mechanisms (hydrogen atom transfer (HAT), single electron transfer-proton transfer (SET-PT), and sequential proton loss electron transfer (SPLET)) have been investigated in five solvents and in the gas phase. The delocalization of the unpaired electrons in the radicals or cation radicals has been explored by the natural bond orbital analysis and the interpretation of spin density maps. The results obtained have proven that the HAT mechanism is the thermodynamically preferred mechanism in the gas phase. But, in the solution phase, the SPLET mechanism has been shown to be more predominant than HAT. The reactivity order of compounds towards selected reactive oxygen species has also been studied.

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Eseyin, Anthonia, E., and Philip, H. Steele. "An overview of the applications of furfural and its derivatives." International Journal of Advanced Chemistry 3, no. 2 (August 24, 2015): 42. http://dx.doi.org/10.14419/ijac.v3i2.5048.

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Recently, furfural, “the sleeping beauty bio-renewable chemical” has gained a renewed attention as a potential chemical for the production of biofuels and biochemicals. Furfural is the most commonly produced industrial chemical because its production is very flexible. It is one of the top value-added chemicals that can be produced from biomass. Furfural and its derivatives have been extensively used in plastics, pharmaceutical and agrochemical industries. Furfural is a natural precursor to a range of furan-based chemicals and solvents such as dihydropyran, methyltetrahydrofuran, tetrahydrofuran, methylfuranfurfuryl alcohol, tetrahydrofurfuryl alcohol and furoic acid. Furfural and its derivatives have been widely applied as fungicides and nematicides, transportation fuels, gasoline additives, lubricants, resins, decolorizing agents, jet fuel blend stocks, drugs, insecticides, bio-plastics, flavor enhancers for food and drinks, rapid all-weather repair system for bomb-damaged runways and pot holes and also for wood modification and book preservation.

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Mansouri, Hadjer, and Sidi Mohamed Mekelleche. "A Computational Study of the Reactions between Dehydrozingerone Derivatives and the Hydroperoxyl Radical in Aqueous and Lipid Media." Journal of Computational Biophysics and Chemistry 20, no. 08 (November 24, 2021): 829–39. http://dx.doi.org/10.1142/s2737416521500514.

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Dehydrozingerone (the half-analogue of curcumin) is a natural product that is isolated from ginger rhizomes. Recent studies have shown that this compound displays several physiological activities including antioxidant properties, and it can scavenge oxygen-free radicals like hydroxyl, peroxyl and superoxide radicals. In this work, the thermodynamic and kinetic aspects of the antiradical activity of the natural dehydrozingerone DHZ0 (R=H) and the designed derivatives DHZ1 (R=CHO), DHZ2 (R=OMe) and DHZ3 (R=NMe2) towards the hydroperoxyl radical (HOO•) were investigated at the M06-2X/6-311[Formula: see text]G([Formula: see text],[Formula: see text]) level of theory. The calculations have been performed in gas phase, pentyl ethanoate and water solvents using the implicit SMD solvation model. Four potential mechanisms have been investigated, namely, hydrogen atom transfer (HAT), single-electron transfer followed by proton transfer (SET-PT), sequential proton loss electron transfer (SPLET) and radical adduct formation (RAF). The obtained results show that the SET-PT and RAF mechanisms are endergonic processes and are thermodynamically disfavored, whereas the exergonic HAT process is predicted as the most thermodynamically favored mechanism in all media. The SPLET mechanism was excluded due the minor proportions of the anion species at physiological pH. Kinetic calculations show that DHZ3 reacts with HOO• 1860, 1250 and 215 times faster than DHZ0 in gas phase, pentyl ethanoate, and water, respectively. Based on thermodynamic and kinetic calculations, the designed compound DHZ3 is predicted as a good candidate for hydroperoxyl scavenging in both polar and nonpolar media. Drug likeness evaluation of the studied DHZ derivatives shows that the pharmacokinetic parameters satisfy all the Lipinski and Veber rules.

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Domergue, Jean-Baptiste, Julie Lalande, Cyril Abadie, and Guillaume Tcherkez. "Compound-Specific 14N/15N Analysis of Amino Acid Trimethylsilylated Derivatives from Plant Seed Proteins." International Journal of Molecular Sciences 23, no. 9 (April 28, 2022): 4893. http://dx.doi.org/10.3390/ijms23094893.

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Isotopic analyses of plant samples are now of considerable importance for food certification and plant physiology. In fact, the natural nitrogen isotope composition (δ15N) is extremely useful to examine metabolic pathways of N nutrition involving isotope fractionations. However, δ15N analysis of amino acids is not straightforward and involves specific derivatization procedures to yield volatile derivatives that can be analysed by gas chromatography coupled to isotope ratio mass spectrometry (GC-C-IRMS). Derivatizations other than trimethylsilylation are commonly used since they are believed to be more reliable and accurate. Their major drawback is that they are not associated with metabolite databases allowing identification of derivatives and by-products. Here, we revisit the potential of trimethylsilylated derivatives via concurrent analysis of δ15N and exact mass GC-MS of plant seed protein samples, allowing facile identification of derivatives using a database used for metabolomics. When multiple silylated derivatives of several amino acids are accounted for, there is a good agreement between theoretical and observed N mole fractions, and δ15N values are satisfactory, with little fractionation during derivatization. Overall, this technique may be suitable for compound-specific δ15N analysis, with pros and cons.

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41

Krakowski, Rafał. "Technical and Ecological Analysis of Different Solutions of the Power Supply of a Marine Diesel Engine." Journal of KONES 26, no. 4 (December 1, 2019): 127–34. http://dx.doi.org/10.2478/kones-2019-0099.

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AbstractThe article contains provisions on the prevention of sea pollution by ships, including, inter alia, the International Convention for the Prevention of Pollution from Ships, developed in 1973 (MARPOL). The convention aims to protect the marine environment from oil and its derivatives. Special areas, where extraordinary measures have been taken to prevent sea pollution, due to the intensity of ship traffic and the greater threat of damage to the marine environment have also been presented. In the further part of the article, the applicability of various pro-ecological solutions, i.e. the use of catalysts, low-sulphur fuels, and in the case of using residual fuels – exhaust gas scrubbers were described. In the main part of the article, a technical and ecological analysis was made. In addition, difficulties resulting from the use of pro-ecological solutions were described. The costs of using low-sulphur fuel meeting the emission standards, installing the scrubber and modification of the natural gas combustion unit were compared with the assumption of ten years of passenger-car ferry sailing. Then the problems that individual solutions create were shown. In the final part of the article, alternatives to those described, i.e. the liquefied natural gas (LNG) power supply, electric and hydrogen drives were presented.

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Maros, Laszlo, Maria Kaldy, and Sarolta Igaz. "Simultaneous determination of bromide and iodide as acetone derivatives by gas chromatography and electron capture detection in natural waters and biological fluids." Analytical Chemistry 61, no. 7 (April 1989): 733–35. http://dx.doi.org/10.1021/ac00182a018.

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43

Christie, William W., Elizabeth Y. Brechany, Susan B. Johnson, and Ralph T. Holman. "A comparison of pyrrolidide and picolinyl ester derivatives for the identification of fatty acids in natural samples by gas chromatography-mass spectrometry." Lipids 21, no. 10 (October 1986): 657–61. http://dx.doi.org/10.1007/bf02537217.

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Lee, Hing-Biu, Yvonne D. Stokker, and Alfred S. Y. Chau. "Chemical Derivatization Analysis of Pesticide Residues. X. Analysis of Ten Acid Herbicides in Natural Waters." Journal of AOAC INTERNATIONAL 69, no. 3 (May 1, 1986): 557–60. http://dx.doi.org/10.1093/jaoac/69.3.557.

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Abstract An improved and augmented gas chromatographic (GC) method using a capillary column and electron capture detector was developed for determination of 10 common acid herbicides in natural water. The herbicides were extracted with methylene chloride after the water sample was acidified to pH < 1. Concentrated extracts in acetone were derivatized with pentafluorobenzyl bromide (PFBBr) to form the corresponding PFB esters. Derivatives were cleaned up on a deactivated silica gel column. A SE-54 fused silica capillary column was used to separate and identify the products. Using this procedure, the method was successfully validated for herbicide concentrations as low as 0.05 μg/L in natural waters. Recoveries of water samples fortified with the 10 herbicides ranging from 1.0 to 0.05 μg/L were 73 to 108% with the exception of picloram which was only 59% recovered at 0.1 μg/L.

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45

Vandervort, Christian, Todd Wetzel, and David Leach. "Engineering And Validating A World Record Gas Turbine." Mechanical Engineering 139, no. 12 (December 1, 2017): 48–50. http://dx.doi.org/10.1115/1.2017-dec-13.

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This article presents an overview of GE’s HA gas turbines that represent the most reliable and efficient machines in the world for converting natural gas into electricity. In a combined cycle arrangement, these turbines provide cost-effective and clean generation that offers reliable electricity to an expanding, global population. The 7/9HA turbine is based upon the original H-class 4-stage gas turbine with exception of simplification by eliminating steam cooling. Metals chosen for the 7/9HA are proven alloys with over 50 million hours of operation on F- and H-class gas turbines. The first 9HA.01 entered commercial operation on June 17, 2016 at the Électricité de France Bouchain plant, located in the Nord Pas-de-Calais region of France. GE followed the Guinness Book of World Records’ definition for a consistent and traceable operating condition for establishing efficiency in world records. Under the oversight of Guinness World Records staff, GE set the record for the world’s most efficient combined-cycle power plant with an efficiency of 62.22% while producing more than 605 MW of electricity.

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Norizan, Mohd Nurazzi, Norli Abdullah, Norhana Abdul Halim, Siti Zulaikha Ngah Demon, and Imran Syakir Mohamad. "Heterojunctions of rGO/Metal Oxide Nanocomposites as Promising Gas-Sensing Materials—A Review." Nanomaterials 12, no. 13 (July 1, 2022): 2278. http://dx.doi.org/10.3390/nano12132278.

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Monitoring environmental hazards and pollution control is vital for the detection of harmful toxic gases from industrial activities and natural processes in the environment, such as nitrogen dioxide (NO2), ammonia (NH3), hydrogen (H2), hydrogen sulfide (H2S), carbon dioxide (CO2), and sulfur dioxide (SO2). This is to ensure the preservation of public health and promote workplace safety. Graphene and its derivatives, especially reduced graphene oxide (rGO), have been designated as ideal materials in gas-sensing devices as their electronic properties highly influence the potential to adsorb specified toxic gas molecules. Despite its exceptional sensitivity at low gas concentrations, the sensor selectivity of pristine graphene is relatively weak, which limits its utility in many practical gas sensor applications. In view of this, the hybridization technique through heterojunction configurations of rGO with metal oxides has been explored, which showed promising improvement and a synergistic effect on the gas-sensing capacity, particularly at room temperature sensitivity and selectivity, even at low concentrations of the target gas. The unique features of graphene as a preferential gas sensor material are first highlighted, followed by a brief discussion on the basic working mechanism, fabrication, and performance of hybridized rGO/metal oxide-based gas sensors for various toxic gases, including NO2, NH3, H2, H2S, CO2, and SO2. The challenges and prospects of the graphene/metal oxide-based based gas sensors are presented at the end of the review.

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Riaz, Nadia, Mohamad Azmi Bustam, Sami Ullah, Ali E. I. Elkhalifah, Girma Gonfa, and Azmi M. Shariff. "Solar-Photocatalytic Degradation of Waste from CO₂ Removal System Using Metal Doped TiO₂ Photocatalysts: Effect of TiO₂ Support." Advanced Materials Research 1133 (January 2016): 532–36. http://dx.doi.org/10.4028/www.scientific.net/amr.1133.532.

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The wastewater containing the spent alkanolamines and its derivatives emerging from the natural gas industries into water has become a critical concern. In the present study, Titanium dioxides was used as photocatalysts to investigate for their efficiency for the photodegradation of Diisopropanolamine (DIPA) containing wastewater under the visible light irradiation. DIPA was used as a model alkanolamine while different commercially available TiO2 were tested for photodegradation of DIPA under the visible light source. The physico-chemical properties of the prepared photocatalysts were analyzed using different characterization techniques including X-ray diffraction (XRD), Raman spectroscopy and N2-physisorption (BET).

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Zhang, Yue, Zhi Li, Xiaodeng Yang, and Tianduo Li. "Synthesis of Chitosan Derivatives and Their Inhibition Effects on Methane Hydrates." Energies 15, no. 7 (April 6, 2022): 2675. http://dx.doi.org/10.3390/en15072675.

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In recent years, the study of natural polymer products such as methane hydrate inhibitors has attracted more and more attention in the scientific research field. In order to achieve environmentally friendly and economical methane hydrate inhibitors with high activity, four chitosan derivatives were successfully synthesized and their methane hydrate inhibition effects were compared with chitosan (CS) and carboxymethyl chitosan (CMCS). Under the conditions of 6 MPa, 1 °C and 400 rpm, the induction time of methane hydrate was prolonged by 7.3 times with the addition of 0.1 wt% CS. It was found that chitosan with high hydrophobicity could effectively prevent methane gas from entering the water solution and reduce the driving force of methane hydrates, resulting in the extension of hydrate induction time. The hydrate inhibition effect of CMCS could be improved by the introduction of hydroxypropyl-3-trimethylamine and N-2-hydroxypropyl-3-isooctyl ether groups based on the enhancement of the molecular hydrophobicity. At the same time, the introduction of the trimethyl quaternary ammonium group increased the ion content in the aqueous solution, which further inhibited the nucleation and growth of methane hydrates. This work is supposed to serve as an inspiration for the further research and development of green kinetic hydrate inhibitors with high-efficiency.

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Elsharif, Asma M., Samar A. Abubshait, Ismail Abdulazeez, and Haya A. Abubshait. "Synthesis of a new class of corrosion inhibitors derived from natural fatty acid: 13‐Docosenoic acid amide derivatives for oil and gas industry." Arabian Journal of Chemistry 13, no. 5 (May 2020): 5363–76. http://dx.doi.org/10.1016/j.arabjc.2020.03.015.

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50

Costa, Rogério F., Marilene S. Oliveira, Antônio S. N. Aguiar, Jean M. F. Custodio, Paolo Di Mascio, José R. Sabino, Giuliana V. Verde, et al. "Synthesis and Structural Studies of Two New Anthracene Derivatives." Crystals 11, no. 8 (August 12, 2021): 934. http://dx.doi.org/10.3390/cryst11080934.

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Anthracene derivatives are an interesting class of compounds and modifications in the anthracene ring, producing different compounds with different properties. Structural analysis of anthracene derivatives with modifications in position 9,10 of the aromatic ring is necessary in order to obtain information about its properties. The introduction of groups with polar substituents increases the possibility to modify the molecule lipophilicity, corroborating its use as bioimaging probes. Anthracene derivatives are used in many biochemical applications. These compounds can react with molecular singlet oxygen [O2 (1Δg)], a reactive oxygen species, through the Diels–Alder reaction [4 + 2] to form the respective endoperoxide and to be used as a chemical trap in biological systems. Thus, the structural and crystalline characterizations of two anthracene derivatives are presented in this work to obtain information about their physical-chemical properties. The compounds were characterized by Fourier-transform infrared spectroscopy, thermogravimetric analyses and scanning electron microscopy. The molecular structures of the compounds were studied by the Density Functional Theory, M06-2X/6-311++G(d,p) level of theory in the gas phase. From the results obtained for the frontier molecular orbitals, HOMO and LUMO, and from the Molecular Electrostatic Potential map, it was possible to predict the chemical properties of both compounds. The supramolecular arrangements were also theoretically studied, whose molecules were kept fixed in their crystallographic positions, through the natural bonding orbitals analysis to check the stability of interactions and the quantum theory of atoms in molecules to verify the type of intermolecular interaction between their molecules, as well as how they occur.

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Journal articles on the topic 'Natural gas derivatives book'

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