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1. (3-Iminio-1-propenyl)oxy-borates: New Acyclic Betaines from Enaminocarbonyl Compounds and Boron Trifluoride or Triphenylboron – Synthesis, Crystal Structure Analysis, and Quantum Chemical Calculations

Author:
Joachim Nikolai; Gerhard Taubmann; Gerhard Maas
Source:
Zeitschrift für Naturforschung B 2014 v.58 no.2-3 pp. 217-225
ISSN:
1865-7117
Subject:
Lewis acids; boron; crystal structure; gases; infrared spectroscopy; moieties; nuclear magnetic resonance spectroscopy; oxygen; stable isotopes
Abstract:
... Adducts of various acyclic enaminoketones and enaminoaldehydes with the Lewis acids boron trifluoride and triphenylboron were prepared. The adducts were characterized by NMR (¹H, ¹³C, ¹¹B) and IR spectroscopy, FAB-MS, and X-ray crystal structure analysis of the adducts of (E)-3- diethylamino-3-phenyl-2-propenal with BF3 (4a) and BPh₃ (5a), respectively. The adduct formation occurs at the oxygen at ...
DOI:
10.1515/znb-2003-2-303

2. (Co-)combustion behaviors and products of spent potlining and textile dyeing sludge

Author:
Guang Sun; Gang Zhang; Jingyong Liu; Wuming Xie; Fatih Evrendilek; Musa Buyukada
Source:
Journal of cleaner production 2019 v.224 pp. 384-395
ISSN:
0959-6526
Subject:
aluminum; ammonia; calcium; calcium oxide; calcium sulfate; carbon disulfide; combustion; fabrics; ferric oxide; gases; hydrogen cyanide; nitric oxide; nitrogen dioxide; sludge; sodium; sodium fluoride; sodium sulfate; sulfur dioxide; temperature; thermodynamics; toxicity; volatilization
Abstract:
... Co-combustion performances, ashes, gases and thermodynamics were quantified for spent potlining (SPL) and textile dyeing sludge (TDS) (with)out CaO. During the four decomposition stages of the blends according to the (D)TG experiments, the interaction among Na, Ca, F, Al, and S led to CaAl2O4, CaF2, and Na2SO4 which converted inorganic compounds into ash. Increased comprehensive combustion index, ...
DOI:
10.1016/j.jclepro.2019.03.208

3. (Co-)combustion of additives, water hyacinth and sewage sludge: Thermogravimetric, kinetic, gas and thermodynamic modeling analyses

Author:
Jingyong Liu; Limao Huang; Guang Sun; Jiacong Chen; Shengwei Zhuang; Kenlin Chang; Wuming Xie; Jiahong Kuo; Yao He; Shuiyu Sun; Musa Buyukada; Fatih Evrendilek
Source:
Waste management 2018 v.81 pp. 211-219
ISSN:
0956-053X
Subject:
Eichhornia crassipes; activation energy; additives; aluminum oxide; ammonia; biomass; carbon dioxide; combustion; emissions; energy; gases; hydrogen cyanide; magnesium carbonate; magnesium oxide; mass spectrometry; nitrogen dioxide; potassium carbonate; sewage sludge; sodium carbonate; sulfur dioxide; thermodynamic models; thermogravimetry; waste management
Abstract:
... Additives and biomass were co-combusted with sewage sludge (SS) to promote SS incineration treatment and energy generation. (Co-)combustion characteristics of sewage sludge (SS), water hyacinth (WH), and 5% five additives (K2CO3, Na2CO3, Mg2CO3, MgO and Al2O3) were quantified and compared using thermogravimetric-mass spectrometric (TG-MS) and numerical analyses. The combustion performance of SS de ...
DOI:
10.1016/j.wasman.2018.09.030

4. (R)-Desmolactone, A Female-produced Sex Pheromone Component of the Cerambycid Beetle Desmocerus californicus californicus (subfamily Lepturinae)

Author:
Ann M. Ray; Ian P. Swift; J. Steven McElfresh; Ronald L. Alten; Jocelyn G. Millar
Source:
Journal of chemical ecology 2012 v.38 no.2 pp. 157-167
ISSN:
0098-0331
Subject:
Coleoptera; antennae; bioassays; enantiomers; females; gases; headspace analysis; males; sex pheromones
Abstract:
... We report the identification, synthesis, and field bioassays of a female-produced sex attractant pheromone for the cerambycid beetle Desmocerus californicus californicus Horn. Headspace volatiles from females contained a sex-specific compound, (R)-desmolactone [(4R,9Z)-hexadec-9-en-4-olide], which elicited strong responses from the antennae of adult males in coupled gas chromatography-electroanten ...
DOI:
10.1007/s10886-012-0070-5
PubMed:
22350519

5. 011 Computation tools in the service of cryomedicine

Author:
Yoed Rabin
Source:
Cryobiology 2013 v.67 no.3 pp. 401
ISSN:
0011-2240
Subject:
computer hardware; cryosurgery; disease course; gases; geometry; image analysis; medical treatment; models; monitoring; planning; system optimization; temperature
Abstract:
... Cryosurgery practices have evolved over the years in close relationship with concurrent technology developments. Well recognized milestones along the path of development are the beginning of commercial production of liquefied gases at the beginning of the 20th century—leading to the widespread of cryosurgery as a medical treatment, the development of the cryostat by Cooper and Lee in the early 196 ...
DOI:
10.1016/j.cryobiol.2013.09.017

6. 1,1′,1′′-(2,4,6-Trihydroxybenzene-1,3,5-triyl)triethanone tautomerism revisited

Author:
Poul Erik Hansen; Fadhil S. Kamounah; Diana Zhiryakova; Yana Manolova; Liudmil Antonov
Source:
Tetrahedron letters 2014 v.55 pp. 354-357
ISSN:
0040-4039
Subject:
acetonitrile; aggregation behavior; benzene; chemical reactions; chemical structure; cyclohexanes; deuterium; gases; hydrogen bonding; isotopes; methanol; nuclear magnetic resonance spectroscopy; phenolic compounds; solvents
Abstract:
... It has recently been suggested that 1,1′,1′′-(2,4,6-trihydroxybenzene-1,3,5-triyl)triethanone may be tautomeric. Using 13C NMR chemical shifts and deuterium isotope effects on 13C chemical shifts, it is demonstrated that this is not the case. This compound occurs as a strongly hydrogen bonded benzene structure with hydrogen bonds between OH groups and the acetyl groups in both non-polar and hydrog ...
DOI:
10.1016/j.tetlet.2013.11.026

7. 1,2,3-Triazoles: Gas Phase Properties

Author:
Wang Kai; Chen Mu; Wang Qiaoyi; Shi Xiaodong; Lee Jeehiun K.
Source:
Journal of organic chemistry 2013 v.78 no.14 pp. 7249-7258
ISSN:
1520-6904
Subject:
acidity; gases; imports; organic chemistry; tautomers; triazoles
Abstract:
... 1,2,3-Triazoles have come to the forefront as compounds of import in a vast number of applications. The fundamental properties of these species, however, remain largely unknown. Herein, the gas phase properties of 4-phenyl-1,2,3-triazole, benzotriazole, and a series of 1-phenylbenzotriazoles are described. Proton affinity and acidity values are computed and measured. Furthermore, ion–molecule reac ...
DOI:
10.1021/jo4012738

8. 1,2,3-Trimethoxypropane: A Glycerol-Derived Physical Solvent for CO2 Absorption

Author:
Flowers Brian S.; Mittenthal Max S.; Jenkins Alexander H.; Wallace David A.; Whitley John W.; Dennis Grayson P.; Wang Mei; Turner C. Heath; Emel’yanenko Vladimir N.; Verevkin Sergey P.; Bara Jason E.
Source:
ACS sustainable chemistry 2017 v.5 no.1 pp. 911-921
ISSN:
2168-0485
Subject:
absorption; animals; carbon dioxide; gases; glycerol; hydrogen; isomers; solubility; solvents; temperature; triacylglycerols; vapor pressure; viscosity
Abstract:
... 1,2,3-Trimethoxypropane (1,2,3-TMP) is the trimethyl ether of propane-1,2,3-triol, better known as glycerol, which can be derived from triglycerides originating from either plant or animal sources. Despite its simple structure and the ubiquity of its glycerol precursor, successful synthesis of 1,2,3-TMP was only recently reported in the literature, with studies suggesting it may be a “green” and n ...
DOI:
10.1021/acssuschemeng.6b02231

9. 1,2-Propanediol as a Surrogate Molecule of Glycerol for Mechanistic Studies of Selective Hydrodeoxygenation Reactions over Mo₂C and Cu/Mo₂C Surfaces

Author:
Zhexi Lin; Weiming Wan; Jingguang G. Chen
Source:
ACS sustainable chemistry & engineering 2019 v.7 no.9 pp. 8077-8082
ISSN:
2168-0485
Subject:
biodiesel; biomass; catalysts; copper; fuel production; gases; glycerol; models; molybdenum; vapor pressure
Abstract:
... The upgrading of glycerol, a byproduct from biodiesel production, is important for developing more sustainable biomass conversion technologies. Nonetheless, the low vapor pressure and structural complexity of glycerol limit mechanistic studies of gas-phase reactions on model surfaces and powder catalysts. In this work, we demonstrate the feasibility of using 1,2-propanediol (PDO) as a surrogate co ...
DOI:
10.1021/acssuschemeng.9b01051

10. 1,3-Dimethyl-3-silapiperidine: Synthesis, Molecular Structure, and Conformational Analysis by Gas-Phase Electron Diffraction, Low Temperature NMR, IR and Raman Spectroscopy, and Quantum Chemical Calculations

Author:
Shainyan Bagrat A.; Kirpichenko Svetlana V.; Kleinpeter Erich; Shlykov Sergey A.; Osadchiy Dmitriy Yu.; Chipanina Nina N.; Oznobikhina Larisa P.
Source:
Journal of organic chemistry 2013 v.78 no.8 pp. 3939-3947
ISSN:
1520-6904
Subject:
Raman spectroscopy; gases; geometry; molecular conformation; nuclear magnetic resonance spectroscopy; organic chemistry; temperature; thermodynamics
Abstract:
... The first Si–H-containing azasilaheterocycle, 1,3-dimethyl-3-silapiperidine 1, was synthesized, and its molecular structure and conformational properties were studied by gas-phase electron diffraction (GED), low temperature NMR, IR and Raman spectroscopy and quantum chemical calculations. The compound exists as a mixture of two conformers possessing the chair conformation with the equatorial NMe g ...
DOI:
10.1021/jo400289g

11. 1,3-Dioxolane-4-ol Hemiacetal Stores Formaldehyde and Glycolaldehyde in the Gas-Phase

Author:
André K. Eckhardt; Raffael C. Wende; Peter R. Schreiner
Source:
Journal of the American Chemical Society 2018 v.140 no.39 pp. 12333-12336
ISSN:
1520-5126
Subject:
calcium hydroxide; formaldehyde; gases; nuclear magnetic resonance spectroscopy; sugars
Abstract:
... We report the spontaneous gas-phase formation of 1,3-dioxolane-4-ol, a mixed hemiacetal resulting from the addition of glycolaldehyde to formaldehyde. It was spectroscopically characterized by matching matrix IR spectra with coupled cluster computations. The formation of the hemiacetal must be surface-catalyzed owing to the very high computed reaction barrier of 39.8 kcal mol–¹. The reaction barri ...
DOI:
10.1021/jacs.8b07480

12. 1,3-Dipolar cycloaddition of 1H-pyrazinium-3-olate and N1- and C-methyl substituted pyrazinium-3-olates with methyl acrylate: a density functional theory study

Author:
Lydia Rhyman; Hassan H. Abdallah; Sabina Jhaumeer-Laulloo; Luis R. Domingo; John A. Joule; Ponnadurai Ramasami
Source:
Tetrahedron 2011 v.67 no.43 pp. 8383-8391
ISSN:
0040-4020
Subject:
chemical reactions; chemical structure; gases; organic compounds; temperature; thermodynamics
Abstract:
... A DFT study of the 1,3-dipolar cycloaddition of methyl acrylate to 1H-pyrazinium-3-olate and N1- and C-methyl substituted pyrazinium-3-olates, in the gas phase and in THF, has been carried out at the B3LYP/6-31G(d) level. Two stereoisomeric pathways, endo and exo, and two regioisomeric channels, 2-oxo-3,8-diazabicyclo[3.2.1]octane-6-ester and 7-ester products, have been considered. Thermodynamic a ...
DOI:
10.1016/j.tet.2011.08.021

13. 1-Butanol synthesis from ethanol over strontium phosphate hydroxyapatite catalysts with various Sr/P ratios

Author:
Shuhei Ogo; Ayumu Onda; Yukina Iwasa; Kenji Hara; Atsushi Fukuoka; Kazumichi Yanagisawa
Source:
Journal of catalysis 2012 v.296 no. pp. 24-30
ISSN:
0021-9517
Subject:
gases; X-ray photoelectron spectroscopy; hydroxyapatite; catalysts; dimerization; strontium; catalytic activity; ethanol
Abstract:
... Strontium phosphate hydroxyapatites (Sr-HAP) with various Sr/P molar ratios were synthesized under hydrothermal conditions. X-ray photoelectron spectroscopy revealed a close correlation between the near-surface and bulk Sr/P molar ratios of catalyst samples. Sr-HAP catalysts show high 1-butanol selectivity in the gas-phase conversion of ethanol. Sr-HAP catalysts with higher Sr/P molar ratios showe ...
DOI:
10.1016/j.jcat.2012.08.019

14. 1-Dopyl-1,2-(4-hydroxyphenyl)ethene: A flame retardant hardner for epoxy resin

Author:
Bob A. Howell; Gavan W. Lienhart; Veronica J. Livingstone; Darpandeep Aulakh
Source:
Polymer degradation and stability 2020 v.175 pp. 109110
ISSN:
0141-3910
Subject:
bisphenol A; catalysts; epoxides; flame retardants; flammability; gases; heat; polymers; thermal stability
Abstract:
... Treatment of desoxyanisoin with 9,10-dihydro-9-oxaphosphaphenathrene-10-oxide (DOPO) in the presence of an acid catalyst generates an adduct, 1-dopyl-1,2-(4-methoxyphenyl)ethene which may be readily converted to the corresponding diphenolic compound, 1-dopyl-1,2-(4-hydroxyphenyl)ethene (BDE). This material behaves as an effective curing agent for the diglycidyl ether of bisphenol A (DGEBA) to prov ...
DOI:
10.1016/j.polymdegradstab.2020.109110

15. 1-MCP application to prolong avocado shelflife

Author:
I. A. M. Amin; R. Poerwanto; J. G. Kartika
Source:
Acta horticulturae 2016 no.1120 pp. 131-136
ISSN:
0567-7572
Subject:
1-methylcyclopropene; avocados; cell respiration; color; ethylene; fruits; gases; ripening; shelf life; weight loss
Abstract:
... 1-MCP inhibits the activity of ethylene by blocking ethylene perception. For climacteric fruits like avocado, 1-MCP application is expected to delay the climacteric process, so as to extend shelf-life. In this study, 1-MCP application was made in two forms, gases with concentrations of 0, 0.2 and 0.4 µL L-1, and a solution with a concentration of 0, 0.3, and 0.6 µL L-1. The results showed that 1-M ...
DOI:
10.17660/ActaHortic.2016.1120.19

16. 1-Methylthio-1-phenyl-1-silacyclohexane: Synthesis, conformational preferences in gas and solution by GED, NMR and theoretical calculations

Author:
Bagrat A. Shainyan; Elena N. Suslova; Tran Dinh Phien; Sergey A. Shlykov; Matthias Heydenreich; Erich Kleinpeter
Source:
Tetrahedron 2019 pp. -
ISSN:
0040-4020
Subject:
carbon; chemical reactions; chemical structure; gases; nuclear magnetic resonance spectroscopy; organic compounds; quantum mechanics; silicon; stable isotopes; sulfur; temperature
Abstract:
... 1-Methylthio-1-phenyl-1-silacyclohexane 1, the first silacyclohexane with the sulfur atom at silicon, was synthesized and its molecular structure and conformational preferences studied by gas-phase electron diffraction (GED) and low temperature 13C and 29Si NMR spectroscopy (LT NMR). Quantum-chemical calculations were carried out both for the isolated species and solvate complexes in gas and in po ...
DOI:
10.1016/j.tet.2019.130677

17. 10-Month characterization of the aerosol number size distribution and related air quality and meteorology at the Bondville, IL Midwestern background site

Author:
Robert L. Bullard; Ashish Singh; Sybil M. Anderson; Christopher M.B. Lehmann; Charles O. Stanier
Source:
Atmospheric environment 2017 v.154 pp. 348-361
ISSN:
1352-2310
Subject:
sulfur dioxide; air quality; ammonia; gases; winter; meteorology; atmospheric chemistry; aerosols; spring; particulates; burning; summer; optical properties; Illinois
Abstract:
... The aerosol size distribution was measured at a rural continental U.S. location (Bondville, Illinois 40.05∘N and 88.37∘W) for the period July 2013–June 2014. The dehumidified size distribution in the range 3 nm to 2.5 μm was continuously recorded by two scanning mobility particle sizers and an aerodynamic particle sizer. The Illinois measurement site is significant because it is home to one of the ...
DOI:
10.1016/j.atmosenv.2016.12.055

18. 104 Super Critical Nitrogen: Assessing the performance and thermal characteristics of a novel cryosurgical device

Author:
Anthony T. Robilotto; Kristi K. Snyder; Kimberly L. Santucci; John M. Baust; Robert G. Van Buskirk; Andrew A. Gage; John G. Baust
Source:
Cryobiology 2013 v.67 no.3 pp. 427
ISSN:
0011-2240
Subject:
argon (noble gases); cold; cooling; freezing; gases; gels; heat; industry; muscles; nitrogen; swine; temperature; thermal properties
Abstract:
... Today’s cryosurgical devices can be characterized by the type of cryogen employed. The most common, and current industry standard, utilizes a gas undergoing Joule-Thomson (JT) cooling. These gaseous cryogen devices can use small diameter probes that generate freezing temperatures near instantaneous, but due to the sub-optimal heat extraction of gases, often require large numbers of probes and/or e ...
DOI:
10.1016/j.cryobiol.2013.09.110

19. 110th Anniversary: Accurate Modeling of the Simultaneous Absorption of H₂S and CO₂ in Aqueous Amine Solvents

Author:
Ismail I. I. Alkhatib; Luis M. C. Pereira; Lourdes F. Vega
Source:
Industrial & engineering chemistry process design and development 2019 v.58 no.16 pp. 6870-6886
ISSN:
1520-5045
Subject:
absorption; amines; carbon dioxide; chemical reactions; equations; ethanolamine; gases; hydrogen sulfide; prediction; process design; screening; solvents; thermodynamic models
Abstract:
... We present results concerning the application of soft statistical associating fluid theory (soft-SAFT), a molecular-based equation, for modeling the absorption of carbon dioxide and hydrogen sulfide in several aqueous amines, including monoethanolamine, diethanolamine, and N-methyldiethanolamine, at conditions of relevance for acid gas separation. The chemisorption of CO₂ and H₂S in aqueous amines ...
DOI:
10.1021/acs.iecr.9b00862

20. 110th Anniversary: Comments on Heterogeneity of Practical Adsorbents

Author:
S. Sircar; T. C. Golden
Source:
Industrial & engineering chemistry process design and development 2019 v.58 no.25 pp. 10984-11002
ISSN:
1520-5045
Subject:
activated carbon; adsorbents; adsorption; ethylene; gases; kinetics; liquids; mass transfer; simulation models; sorption isotherms
Abstract:
... Most micro–mesoporous adsorbents used in practical adsorptive fluid (gas and liquid) separation processes are energetically heterogeneous. The adsorbent heterogeneity plays a significant role in establishing the shapes of the equilibrium adsorption isotherms (pure component or mixture), the corresponding heats of adsorption, and the adsorbate mass-transfer rates, which in turn determine the overal ...
DOI:
10.1021/acs.iecr.9b01025

21. 110th Anniversary: Fluidized-Bed Chemical Reactors for Heterogeneously Catalyzed Gas–Solid Reactions: Old and New Applications

Author:
Leslaw Mleczko
Source:
Industrial & engineering chemistry process design and development 2019 v.58 no.47 pp. 21173-21186
ISSN:
1520-5045
Subject:
biomass; carbon nanotubes; catalysts; catalytic activity; ethylene; fluidized beds; gases; polymerization; propylene; pyrolysis; rubber; silicon; value-added products; wastes
Abstract:
... In this review, the potential of fluidized-bed technology for heterogeneously catalyzed gas–solid reactions is discussed. This reaction class can be divided into three reaction categories: gas-to-solid (G2S), solid-to-gas (S2G), and solid-to-gas-to-gas (S2G2G). The established examples of G2S reactions are the gas-phase polymerizations of ethylene and propylene. However, other concepts, such as po ...
DOI:
10.1021/acs.iecr.9b03515

22. 110th Anniversary: New Volumetric Frequency Response System for Determining Mass Transfer Mechanisms in Microporous Adsorbents

Author:
Mohammad I. Hossain; Charles E. Holland; Armin D. Ebner; James A. Ritter
Source:
Industrial & engineering chemistry process design and development 2019 v.58 no.37 pp. 17462-17474
ISSN:
1520-5045
Subject:
adsorbents; atmospheric pressure; carbon dioxide; differential pressure; gases; heat; mass transfer; pellets; porous media; process design; temperature; zeolites
Abstract:
... A new volumetric frequency response (VFR) system was developed for studying the mass transfer characteristics of gases in microporous adsorbents. For this VFR system, the differential pressure response from a small perturbation in volume was measured in a closed system after equilibrium was established for a gas adsorbate–adsorbent pair at constant temperature and pressure. It operates over a wide ...
DOI:
10.1021/acs.iecr.9b02422

23. 110th Anniversary: Sustainable Synthesis of Zeolites: From Fundamental Research to Industrial Production

Author:
Qinming Wu; Ye Ma; Sai Wang; Xiangju Meng; Feng-Shou Xiao
Source:
Industrial & engineering chemistry process design and development 2019 v.58 no.27 pp. 11653-11658
ISSN:
1520-5045
Subject:
adsorption; carbon dioxide; catalytic activity; gases; industrial applications; ion exchange; micropores; nitrogen oxides; porous media; process design; solvents; toxicity; water pollution; zeolites
Abstract:
... Zeolites, as a class of porous materials with ordered networks of micropores, have been widely used for decades in industrial applications such as catalysis, ion exchange, and adsorption and separation. In general, their syntheses are not sustainable, because hydrothermal synthesis requires the presence of costly and toxic organic templates and a large amount of a solvent such as water; the remova ...
DOI:
10.1021/acs.iecr.9b02054

24. 15. Control of ice formation in biological samples

Author:
Ido Braslavsky
Source:
Cryobiology 2015 v.71 no.1 pp. 168
ISSN:
0011-2240
Subject:
binding proteins; cooling; cryopreservation; crystallization; crystals; energy; gases; ice; ice nucleation; liquids; melting; melting point; metabolism; osmotic stress; solidification; solutes; sonication; supercooling; temperature; tissues; viscosity; vitrification; water content
Abstract:
... Lowering the temperature of a biological sample reduces the pace of biochemical metabolism and ultimately stops it altogether. This process, in combination with rewarming the sample with minimal tissue damage, is the essence of cryopreservation. A key obstacle to successful cryopreservation is that, as the biological material is cooled, liquid water within the sample may reorganize into a more sta ...
DOI:
10.1016/j.cryobiol.2015.05.021

25. 185 nm Photoreduction of CO2 to Methane by Water. Influence of the Presence of a Basic Catalyst

Author:
Sastre Francesc; Corma Avelino; García Hermenegildo
Source:
Journal of the American Chemical Society 2012 v.134 no.34 pp. 14137-14141
ISSN:
1520-5126
Subject:
carbon dioxide; carbon monoxide; energy; gases; hydrogen; irradiation; mercury; methane; photocatalysts; photolysis; reducing agents; wavelengths; zeolites
Abstract:
... Photolysis of CO₂ at 185 nm using a Hg lamp in the presence of H₂ or H₂O leads to the formation of CH₄ (after an induction period) and a lesser amount of CO. Using H₂ gas as reducing agent, up to 40% conversion was achieved with almost complete selectivity to methane and energy consumption of 1.55 Gcal/mol. When CO₂ irradiation is carried out in the gas phase in the presence of H₂O, both reagents ...
DOI:
10.1021/ja304930t

26. 1T′-MoS₂, A Promising Candidate for Sensing NOₓ

Author:
Yaoyao Linghu; Chao Wu
Source:
Journal of physical chemistry 2019 v.123 no.16 pp. 10339-10345
ISSN:
1932-7455
Subject:
adsorption; ammonia; carbon dioxide; carbon monoxide; engineering; gases; molybdenum disulfide; nitric oxide; nitrogen dioxide; sulfur dioxide; tensile strength
Abstract:
... Recently, ultrathin MoS₂ sheets in the semiconducting 2H phase have been fabricated into high-performance gas sensors. Here, we investigated the gas-sensing behavior of MoS₂ in the metallic 1T′ phase via first-principles calculations. We found that monolayered and few-layered 1T′-MoS₂ exhibit high selectivity and sensitivity toward NO molecules. Moreover, the adsorption of NO and NO₂ molecules on ...
DOI:
10.1021/acs.jpcc.9b00051

27. 2-(Methylamino)ethanol for CO2 Absorption in a Bubble Reactor

Author:
Folgueira I.; Teijido I.; García-Abuín A.; Gómez-Díaz D.; Rumbo A.
Source:
Energy & Fuels 2014 v.28 no.7 pp. 4737-4745
ISSN:
1520-5029
Subject:
absorption; aqueous solutions; bicarbonates; bioreactors; carbon dioxide; gases; hydrodynamics; hydrolysis; mass transfer; nuclear magnetic resonance spectroscopy
Abstract:
... This paper deals with the study of carbon dioxide capture using 2-(methylamino)ethanol (MAE) aqueous solutions. The reaction was studied in a bubble column reactor (BCR), and the most important aspects of the process, such as the hydrodynamic behavior (bubble size distribution, gas holdup, and interfacial area) and absorption phenomena (load of carbon dioxide and mass-transfer coefficient on the l ...
DOI:
10.1021/ef500923b

28. 2-Propanol As a Co-Guest of Structure II Hydrates in the Presence of Help Gases

Author:
Lee Youngjun; Lee Seungmin; Park Sungwon; Kim Yunju; Lee Jong-Won; Seo Yongwon
Source:
Journal of physical chemistry 2013 v.117 no.8 pp. 2449-2455
ISSN:
1520-5207
Subject:
carbon dioxide; chemical elements; gases; isopropyl alcohol; methane; nuclear magnetic resonance spectroscopy; physical chemistry
Abstract:
... The enclathration of 2-propanol (2-PrOH) as a co-guest of structure II (sII) hydrates in the presence of CH₄ and CO₂ was experimentally verified with a focus on macroscopic phase behaviors and microscopic analytical methods such as powder X-ray diffraction (PXRD) and NMR spectroscopy. 2-PrOH functioned as a hydrate promoter in the CH₄ + 2-PrOH systems, whereas it functioned as an apparent hydrate ...
DOI:
10.1021/jp310487w

29. 2-Pyridone and Derivatives: Gas-Phase Acidity, Proton Affinity, Tautomer Preference, and Leaving Group Ability

Author:
Michelson Anna Zhachkina; Petronico Aaron; Lee Jeehiun K.
Source:
Journal of organic chemistry 2012 v.77 no.4 pp. 1623-1631
ISSN:
1520-6904
Subject:
acidity; chemical reactions; gases; mass spectrometry; moieties; organic chemistry; organic compounds; tautomers
Abstract:
... The fundamental properties of the parent and substituted 2-pyridones (2-pyridone, 3-chloro-2-pyridone, and 3-formyl-2-pyridone) have been examined in the gas phase using computational and experimental mass spectrometry methods. Newly measured acidities and proton affinities are reported and used to ascertain tautomer preference. These particular substrates (as well as additional 3-substituted pyri ...
DOI:
10.1021/jo201991y

30. 220Rn/222Rn Isotope Pair as a Natural Proxy for Soil Gas Transport

Author:
Huxol Stephan; Brennwald Matthias S.; Henneberger Ruth; Kipfer Rolf
Source:
Environmental Science & Technology 2013 v.47 no.24 pp. 14044-14050
ISSN:
1520-5851
Subject:
gases; half life; isotopes; laboratory experimentation; radionuclides; radon; soil air; soil transport processes; tracer techniques
Abstract:
... Radon (Rn) is a naturally occurring radioactive noble gas, which is ubiquitous in soil gas. Especially, its long-lived isotope ²²²Rn (half-life: 3.82 d) gained widespread acceptance as a tracer for gas transport in soils, while the short-lived ²²⁰Rn (half-life: 55.6 s) found less interest in environmental studies. However, in some cases, the application of ²²²Rn as a tracer in soil gas is complex ...
DOI:
10.1021/es4026529

31. 2D profiles of CO2, CH4, N2O and gas diffusivity in a well aerated soil: measurement and Finite Element Modeling

Author:
M. Maier; B. Longdoz; T. Laemmel; H. Schack-Kirchner; F. Lang
Source:
Agricultural and forest meteorology 2017 v.247 pp. 21-33
ISSN:
0168-1923
Subject:
Pinus sylvestris; autumn; carbon dioxide; carbon dioxide production; carbon tetrafluoride; diffusivity; finite element analysis; gases; methane; models; nitrous oxide; physical properties; rhizosphere; roots; soil air; soil profiles; soil sampling; sulfur hexafluoride; topsoil; Germany
Abstract:
... Soil gas fluxes depend on soil gas concentrations and physical properties of a soil. Taking soil samples for physical analysis into the laboratory strongly modifies soil gas concentrations and also cuts roots that sustain the activity in the rhizosphere. Since microbial processes interact with gas concentrations in soil, we need to study gas transport and production in situ.We developed a method t ...
DOI:
10.1016/j.agrformet.2017.07.008

32. 3-Aminopropyltriethoxysilane functionalized inorganic membranes for high temperature CO₂/N₂ separation

Author:
Mayur Ostwal; Rajinder Pal Singh; Steve F. Dec; Mark T. Lusk; J. Douglas Way
Source:
Journal of membrane science 2011 v.369 no.1-2 pp. 139-147
ISSN:
0376-7388
Subject:
activation energy; adsorption; artificial membranes; carbon dioxide; energy; gases; methane; nitrogen; nuclear magnetic resonance spectroscopy; porosity; silica; temperature
Abstract:
... High temperature inorganic membranes may play an important role in the development of economical processes for pre-combustion and/or post-combustion CO₂ capture. The CO₂/N₂ selectivity of mesoporous silica membranes is enhanced by surface modification using APTS (3-aminopropyl-triethoxy silane). Unmodified silica membranes exhibit Knudsen diffusion behavior for most gases but also have some contri ...
DOI:
10.1016/j.memsci.2010.11.053

33. 3-D agricultural air quality modeling: Impacts of NH3/H2S gas–phase reactions and bi-directional exchange of NH3

Author:
Kai Wang; Yang Zhang
Source:
Atmospheric environment 2014 v.98 pp. 554-570
ISSN:
1352-2310
Subject:
air quality; ammonia; ammonium nitrate; atmospheric chemistry; dry deposition; gases; hydrogen sulfide; models; nitrogen; nitrogen content; ozone; particulates; relative humidity; sulfates; sulfur dioxide; temperature; uncertainty; Eastern United States
Abstract:
... Accurately simulating the transport and fate of reduced nitrogen (NHx = ammonia (NH3) + ammonium (NH4+))- and sulfur-containing compounds emitted from agricultural activities represents a major challenge in agricultural air quality modeling. In this study, the Community Multiscale Air Quality (CMAQ) modeling system is further developed and improved by implementing 22 ammonia (NH3)/hydrogen sulfide ...
DOI:
10.1016/j.atmosenv.2014.09.010

34. 31. Computation tools at the forefront of cryosurgery development

Author:
Yoed Rabin
Source:
Cryobiology 2013 v.66 no.3 pp. 351
ISSN:
0011-2240
Subject:
computer hardware; cryosurgery; disease course; gases; geometry; image analysis; medical treatment; models; monitoring; planning; system optimization; temperature
Abstract:
... Cryosurgery practices have evolved over the years in close relationship with concurrent technology developments. Well recognized milestones along the path of development are the beginning of commercial production of liquefied gases at the beginning of the 20th century; leading to the widespread of cryosurgery as a medical treatment, the development of the cryostat by Cooper and Lee in the early 19 ...
DOI:
10.1016/j.cryobiol.2013.02.037

35. 3D Voronoi grid dedicated software for modeling gas migration in deep layered sedimentary formations with TOUGH2-TMGAS

Author:
Stefano Bonduà; Alfredo Battistelli; Paolo Berry; Villiam Bortolotti; Alberto Consonni; Carlo Cormio; Claudio Geloni; Ester Maria Vasini
Source:
Computers and Geosciences 2017 pp. -
ISSN:
0098-3004
Subject:
basins; case studies; computer software; gases; mathematical models; prisms
Abstract:
... As is known, a full three-dimensional (3D) unstructured grid permits a great degree of flexibility when performing accurate numerical reservoir simulations. However, when the Integral Finite Difference Method (IFDM) is used for spatial discretization, constraints (arising from the required orthogonality between the segment connecting the blocks nodes and the interface area between blocks) pose dif ...
DOI:
10.1016/j.cageo.2017.03.008

36. 3D characterisation of the thermohaline structure in the southwestern tropical Atlantic derived from functional data analysis of in situ profiles

Author:
Ramilla V. Assunção; Alex C. Silva; Amédée Roy; Bernard Bourlès; Carlos Henrique S. Silva; Jean-François Ternon; Moacyr Araujo; Arnaud Bertrand
Source:
Progress in oceanography 2020 v.187 pp. 102399
ISSN:
0079-6611
Subject:
autumn; climate; gases; heat transfer; models; nutrient availability; salinity; spring; statistical analysis; Fernando de Noronha
Abstract:
... The dynamic of the thermohaline structure of the upper ocean, which depends on ocean–atmosphere interactions, drives most near surface oceanic processes, including the control of gases and heat fluxes, and nutrient availability in the photic layer. The thermohaline structure of the southwestern tropical Atlantic (SWTA), a key region for diagnosing variation of the Atlantic Meridional Overturning C ...
DOI:
10.1016/j.pocean.2020.102399

37. 3D graphene aerogel-supported SnO₂ nanoparticles for efficient detection of NO₂

Author:
Xin Liu; Jiashan Cui; Jianbo Sun; Xitian Zhang
Source:
RSC advances 2014 v.4 no.43 pp. 22601-22605
ISSN:
2046-2069
Subject:
aerogels; ambient temperature; freeze drying; gases; graphene; graphene oxide; nanocomposites; nanoparticles; nitrogen dioxide; porous media; tin dioxide
Abstract:
... Three-dimensional (3D) graphene aerogel-supported SnO₂ (SGA) nanoparticles (NPs) are presented by a one-pot solvothermal treatment of graphene oxide in the presence of SnCl₄ followed by freeze drying. The size of SnO₂ nanoparticles on the graphene aerogel is as small as 5–10 nm with uniform distribution. The 3D SnO₂–graphene aerogel exhibits interconnected macroporous networks which will be benefi ...
DOI:
10.1039/c4ra02453b

38. 3D in situ observations of the compressibility and pore transport in Sheet Moulding Compounds during the early stages of compression moulding

Author:
D. Ferré Sentis; L. Orgéas; P.J.J. Dumont; S. Rolland du Roscoat; M. Sager; P. Latil
Source:
Composites 2017 v.92 pp. 51-61
ISSN:
1359-835X
Subject:
X-radiation; composite materials; compressibility; compression molding; fiber content; gases; manufacturing; permeability; porosity
Abstract:
... The properties of Sheet Moulding Compounds (SMCs) are altered by their porosity induced during the manufacturing or moulding of these prepregs. To characterise the pore scale mechanisms occurring during SMC flow, 3D synchrotron X-ray images were acquired during the compression of two uncured SMCs. For the high fibre content SMC (50wt%), with a high porosity, pores mainly decreased in size and disa ...
DOI:
10.1016/j.compositesa.2016.10.031

39. 5-Isopropylbarbituric and 2-thiobarbituric acids: An experimental and computational study

Author:
Piotr Szterner; Tiago L.P. Galvão; Luísa M.P.F. Amaral; Maria D.M.C. Ribeiro da Silva; Manuel A.V. Ribeiro da Silva
Source:
Thermochimica acta 2016 v.625 pp. 36-46
ISSN:
0040-6031
Subject:
calorimetry; combustion; enthalpy; equations; gases; sublimation; temperature; thiobarbituric acid
Abstract:
... The standard (pᵒ=0.1MPa) molar energies of combustion, ΔcUmo, for the crystalline 5-isopropylbarbituric and 2-thiobarbituric acids were determined, at the temperature of 298.15K, by static bomb or rotating bomb combustion calorimetry, respectively. For 5-isopropylbarbituric acid, the standard molar enthalpy of sublimation, ΔcrgHmo, at T=298.15K, was derived by Calvet microcalorimetry. The standard ...
DOI:
10.1016/j.tca.2015.12.007

40. 6,6′-Disulfide Cross-Links in Cotton Cellulose; Part II: Effects of Different Cross-Linking Conditions

Author:
Robert F. Schwenker; Leonard Lifland
Source:
Textile research journal v.33 no.2 pp. 107-117
ISSN:
1746-7748
Subject:
cellulose; cotton; cotton fabric; crosslinking; gases; oxidation; textile fibers
Abstract:
... The effects of covalent, intermolecular cross-linking resulting from the introduction into cellulose of thio (SH) groups which are subsequently oxidized to form disulfide (S—S) linkages between the cellulose chains are discussed. When the reactions described herein are carried out on cotton fabrics, there is enhanced wet and/or dry wrinkle recovery, depending upon the mode of thio group oxidation. ...
DOI:
10.1177/004051756303300203

41. 6. Overview of GI indications and cryo technology via flexible endoscopy

Author:
Anthony N. Kalloo
Source:
Cryobiology 2013 v.66 no.3 pp. 344
ISSN:
0011-2240
Subject:
abnormal development; animal models; carbon dioxide; case studies; catheters; clinical trials; cryosurgery; duodenal ulcers; endoscopy; esophagus; freezing; gases; gastritis; gastrointestinal neoplasms; gastrointestinal system; hemorrhage; mucosa; nitrogen; nitrous oxide; temperature
Abstract:
... Since the mid-1960s, Cryotherapy was a technique in search of an indication for gastrointestinal diseases. In those early days, Cryotherapy although hampered by technical challenges was advocated for treating duodenal ulcers, gastric erosions, and hemorrhagic gastritis. By this time, Cryotherapy was showing great promise in other clinical areas such as dermatologic and prostatic conditions. Despit ...
DOI:
10.1016/j.cryobiol.2013.02.012

42. 99Tc immobilization from off-gas waste streams using nickel-doped iron spinel

Author:
Guohui Wang; Wooyong Um; Dong-Sang Kim; Albert A. Kruger
Source:
Journal of hazardous materials 2019 v.364 pp. 69-77
ISSN:
0304-3894
Subject:
X-ray absorption spectroscopy; X-ray diffraction; chromium; digestion; gases; iron; minerals; nickel; waste treatment
Abstract:
... Technetium-99 (⁹⁹Tc) incorporation within stable spinel phases is a novel method for ⁹⁹Tc removal and immobilization from waste streams. In this study, transformation of Ni-doped Fe(OH)₂(s) to spinel minerals, e.g. trevorite (NiFe₂O₄), is explored as a method for removing ⁹⁹Tc from Hanford Waste Treatment and Immobilization Plant (WTP) primary off-gas waste stream simulant. The Fe(OH)₂(s) transfor ...
DOI:
10.1016/j.jhazmat.2018.09.064

43. A 1-D coordination polymer route to catalytically active Co@C nanoparticles

Author:
Anand Pariyar; Siddharth Gopalakrishnan; Joseph Stansbery; Rajankumar L. Patel; Xinhua Liang; Nikolay Gerasimchuk; Amitava Choudhury
Source:
RSC advances 2016 v.6 no.45 pp. 38533-38540
ISSN:
2046-2069
Subject:
carbon; carboxylic acids; catalytic activity; cobalt; coordination polymers; gases; models; nanoparticles; nitrophenols; pyrolysis
Abstract:
... Pyrolysis of a 1-D polymeric cobalt(ii) coordination complex ([Co(BDC)(Mim)₂]ₙ, H₂BDC = benzenedicarboxylic acid; Mim = N-methylimidazole) results in the formation of carbon embedded fcc cobalt nanoparticle composites, Co@C. The as-prepared Co@C shows an agglomerated secondary structure with a highly embedded carbon shell comprising of cobalt nanoparticles of 20–100 nm. These Co@C particles show e ...
DOI:
10.1039/c6ra04650a

44. A 3D CFD model for predicting the temperature distribution in a full scale APU SOFC short stack under transient operating conditions

Author:
A. Al-Masri; M. Peksen; L. Blum; D. Stolten
Source:
Applied energy 2014 v.135 pp. 539-547
ISSN:
0306-2619
Subject:
fuel cells; gases; mass flow; mathematical models; prediction; temperature profiles
Abstract:
... During the development process of solid oxide fuel cells (SOFCs) for Auxiliary Power Unit (APU) applications heat-up experiments are performed with hot gases. The inlet temperatures and the mass flow rates of the hot gases are adjusted experimentally to avoid high local thermal gradients and prevent high stresses in the stack components. In order to reduce the experimental effort needed to achieve ...
DOI:
10.1016/j.apenergy.2014.08.052

45. A CFD approach on the effect of particle size on char entrainment in bubbling fluidised bed reactors

Author:
Papadikis, K.; Gu, S.; Bridgwater, A.V.
Source:
Biomass and bioenergy 2010 v.34 no.1 pp. 21-29
ISSN:
0961-9534
Subject:
gases; simulation models; momentum; fluid mechanics; particle size; sand; computer software; fluidized beds
Abstract:
... The fluid - particle interaction inside a 41.7 mg s-1 fluidised bed reactor is modelled. Three char particles of sizes 500 μm, 250 μm, and 100 μm are injected into the fluidised bed and the momentum transport from the fluidising gas and fluidised sand is modelled. Due to the fluidising conditions and reactor design the char particles will either be entrained from the reactor or remain inside the b ...
DOI:
10.1016/j.biombioe.2009.09.007

46. A CO₂-switchable polymer brush for reversible capture and release of proteins

Author:
Surjith Kumar; Xia Tong; Yves L. Dory; Martin Lepage; Yue Zhao
Source:
Chemical communications 2012 v.49 no.1 pp. 90-92
ISSN:
1364-548X
Subject:
acids; adsorption; carbon dioxide; chemical bases; chemical communication; chemical reactions; gases; nitrogen; pH; polymers; proteins
Abstract:
... We report on a polymer brush that can be switched between extended (hydrated) and collapsed (dehydrated) chain conformational states just by passing CO₂ and an inert gas like N₂ in solution alternately. This conformational change allows for reversible adsorption and release of a protein. In contrast to adding acids and bases for pH change, using gases as the trigger makes it possible to repeat the ...
DOI:
10.1039/c2cc36284h

47. A Capacitance Sensor for Water: Trace Moisture Measurement in Gases and Organic Solvents

Author:
Ohira Shin-Ichi; Goto Kayoko; Toda Kei; Dasgupta Purnendu K.
Source:
Analytical chemistry 2012 v.84 no.20 pp. 8891-8897
ISSN:
1520-6882
Subject:
capacitance; detection limit; dewpoint; dialysis; drying; ethanol; flow injection analysis; gas chromatography; gases; phosphoric acid; relative humidity; solvents; temperature
Abstract:
... The determination of water in various matrices is one of the most important analytical measurements. We report on a high-resolution capacitance-based moisture sensor utilizing a thin film of a perfluorosulfonate ionomer (PFSI)–H₃PO₄ composite in a flow-through configuration, for both gas and liquid samples. Incorporation of H₃PO₄ into a PFSI sensing film improved the limit of detection (LOD) (sign ...
DOI:
10.1021/ac3024069

48. A Closed, Well-oxygenated System for the Determination of the Emission of Carbon Dioxide, Nitrous Oxide, and Ammonia

Author:
P. Fine; A. Feigin; Y. Waisel
Source:
Soil Science Society of America journal 1986 v.50 no.6 pp. 1489-1493
ISSN:
0361-5995
Subject:
ammonia; barium carbonate; carbon dioxide; gases; mineralization; nitrogen; nitrous oxide; oxygen; quantitative analysis; soil; soil sampling
Abstract:
... A simple closed system was set up for the measurement of CO₂, N₂O, and NH₃ emission from soil samples kept under well-oxygenated atmosphere. The system is an adaptation of a method suggested by Cornfield (1961a). Carbon dioxide is precipitated from the atmosphere as BaCO₃, while O₂ is generated from a BaO₂ solution in equivalent amounts. With the aid of the proposed method, the simultaneous and qu ...
DOI:
10.2136/sssaj1986.03615995005000060022x

49. A Compact Kinetic Model for Biomass Pyrolysis at Gasification Conditions

Author:
Goyal Himanshu; Pepiot Perrine
Source:
Energy & Fuels 2017 v.31 no.11 pp. 12120-12132
ISSN:
1520-5029
Subject:
biomass; carbon dioxide; carbon monoxide; fluid mechanics; fluidized beds; fuels; gases; gasification; geometry; hydrogen; kinetics; models; oxygen; polycyclic aromatic hydrocarbons; prediction; pyrolysis
Abstract:
... Computational fluid dynamics (CFD) tools are increasingly gaining importance to obtain detailed insight into biomass gasification. A major shortcoming of the current CFD tools to study biomass gasification is the lack of computationally affordable chemical kinetic models, which allows detailed predictions of the yield and composition of various gas and tar species in complex reactor configurations ...
DOI:
10.1021/acs.energyfuels.7b01634

50. A Comparative Study of Immobilized Nitrifying and Co-Immobilized Nitrifying and Denitrifying Bacteria for Ammonia Removal from Sludge Digester Supernatant

Author:
Hill, Christopher B.; Khan, Eakalak
Source:
Water, air, and soil pollution 2008 v.195 no.1-4 pp. 23-33
ISSN:
0049-6979
Subject:
ammonia; anaerobic digesters; calcium alginate; denitrification; denitrifying bacteria; electrons; gases; hydrogen production; methanol; nitrification; nitrites; nitrogen; sludge
Abstract:
... Bench scale kinetic experiments were conducted to examine the use of cell immobilization in calcium alginate to remove ammonia in anaerobic sludge digester supernatant. Two systems, immobilized nitrifiers and co-immobilized nitrifiers and denitrifiers, were studied with and without the addition of methanol. Results indicated that partial nitrification (to nitrite) was achieved in both systems. The ...
DOI:
10.1007/s11270-008-9724-x

51. A Comparison of Trace Gases and Particulate Matter over Beijing (China) and Delhi (India)

Author:
Sheng Zheng; Ramesh P. Singh; Yuzhe Wu; Cifang Wu
Source:
Water, air, and soil pollution 2017 v.228 no.5 pp. 181
ISSN:
0049-6979
Subject:
World Health Organization; air pollution; burden of disease; carbon monoxide; cities; diurnal variation; gases; mortality; nitric oxide; nitrogen dioxide; ozone; particulates; pollutants; suburban areas; summer; urban areas; winter; China; India
Abstract:
... Air pollution represents a significant fraction of the total mortality estimated by the World Health Organization (WHO) global burden of disease project (GBD). The present paper discusses the characteristics of trace gases (O₃, NO, NO₂, and CO) and particulate matter (PM₁₀ and PM₂.₅) in two Asian megacities, Delhi (India) and Beijing (China). A continuous measurement of trace gases and particulat ...
DOI:
10.1007/s11270-017-3360-2

52. A Compensating Method for Measuring Carbon Dioxide Exchange, Transpiration, and Diffusive Resistance of Plants under Controlled Environmental Conditions

Author:
F. A. Bazzaz; J. S. Boyer
Source:
Ecology 1972 v.53 no.2 pp. 343-349
ISSN:
0012-9658
Subject:
Ambrosia trifida; carbon dioxide; environmental factors; gases; leaf area; leaves; light intensity; mesophyll; photosynthesis; relative humidity; temperature; transpiration; wind speed
Abstract:
... A semi—closed compensating system is described for measuring CO₂ exchange and transpiration simultaneously under controlled environmental conditions. The compensating feature permits conditions in the assimilation chamber to be kept uniform and within narrow limits. Temperature, relative humidity, carbon dioxide concentration, wind speed, and light intensity may be varied within the system. Since ...
DOI:
10.2307/1934091

53. A Conformational Analysis of the Spirocyclic Quaternary Ammonium Cation [(CH2)4N(CH2)4]+ in its Bromide and Picrate Salts

Author:
Uwe Monkowius; Stefan Nogai; Hubert Schmidbaur
Source:
Zeitschrift für Naturforschung 2014 v.59 no.3 pp. 259-263
ISSN:
0932-0776
Subject:
ammonium; bromides; gases; molecular conformation; nuclear magnetic resonance spectroscopy
Abstract:
... High-yield syntheses of the bromide (1a) and picrate salts (1b) of the 5-azonia-spiro[4]nonane cation [(CH₂)₄N(CH₂)₄]⁺ are reported. In the single crystal X-ray diffraction analyses of the two salts the spirocyclic quaternary ammonium cations have their five-membered rings in envelop and twist conformations modified by packing forces. The conformation found experimentally for 1a has C2-symmetry as ...
DOI:
10.1515/znb-2004-0303

54. A Critical Review of State-of-the-Art and Emerging Approaches to Identify Fracking-Derived Gases and Associated Contaminants in Aquifers

Author:
J. C. McIntosh; M. J. Hendry; C. Ballentine; R. S. Haszeldine; B. Mayer; G. Etiope; M. Elsner; T. H. Darrah; A. Prinzhofer; S. Osborn; L. Stalker; O. Kuloyo; Z.-T. Lu; A. Martini; B. Sherwood Lollar
Source:
Environmental science & technology 2018 v.53 no.3 pp. 1063-1077
ISSN:
1520-5851
Subject:
aquifers; carbon sequestration; coal; gases; greenhouse gases; groundwater; hydraulic fracturing; hydrogen; methane; natural gas; oils; pollution; radioactive waste; sandstone; Australia; Canada; United States
Abstract:
... High-volume, hydraulic fracturing (HVHF) is widely applied for natural gas and oil production from shales, coals, or tight sandstone formations in the United States, Canada, and Australia, and is being widely considered by other countries with similar unconventional energy resources. Secure retention of fluids (natural gas, saline formation waters, oil, HVHF fluids) during and after well stimulati ...
DOI:
10.1021/acs.est.8b05807

55. A Critical Review of the Risks to Water Resources from Unconventional Shale Gas Development and Hydraulic Fracturing in the United States

Author:
Vengosh Avner; Jackson Robert B.; Warner Nathaniel; Darrah Thomas H.; Kondash Andrew
Source:
Environmental Science & Technology 2014 v.48 no.15 pp. 8334-8348
ISSN:
1520-5851
Subject:
aquifers; case studies; drilling; gases; groundwater; human health; isotopes; natural gas; oil fields; radium; risk; sediments; shale; soil; streams; subsurface flow; surface water; toxicity; wastewater; water shortages; United States
Abstract:
... The rapid rise of shale gas development through horizontal drilling and high volume hydraulic fracturing has expanded the extraction of hydrocarbon resources in the U.S. The rise of shale gas development has triggered an intense public debate regarding the potential environmental and human health effects from hydraulic fracturing. This paper provides a critical review of the potential risks that s ...
DOI:
10.1021/es405118y

56. A CuO–ZnO nanostructured p–n junction sensor for enhanced N-butanol detection

Author:
Yalu Chen; Zhurui Shen; Qianqian Jia; Jiang Zhao; Zhe Zhao; Huiming Ji
Source:
RSC advances 2016 v.6 no.3 pp. 2504-2511
ISSN:
2046-2069
Subject:
butanol; cupric oxide; detection limit; gases; hot water treatment; nanosheets; zinc oxide
Abstract:
... Herein, a novel CuO–ZnO nanostructured p–n junction composite is prepared via the hydrothermal method. It is composed of a ZnO two dimensional (2-D) porous nanosheet assembly and leaf-like 2-D CuO nanoplates. Then, its gas sensing performance toward n-butanol is studied. The 2-D/2-D CuO–ZnO composite sensor shows 2.7 times higher sensitivity than that of pure ZnO at 220 °C. Moreover, its response ...
DOI:
10.1039/c5ra20031h

57. A DEM investigation of transitional behaviour in gas-fluidised beds

Author:
Colin Thornton; Fang Yang; Jonathan Seville
Source:
Powder technology 2015 v.270 pp. 128-134
ISSN:
0032-5910
Subject:
bubbles; fluidized beds; gases; physical properties; powders
Abstract:
... Using DEM simulations, the paper examines the different types of behaviour as the gas velocity is increased to cover the complete range from fixed bed to homogeneous expansion, bubbling, turbulent and fast fluidisation. The paper highlights the transitions between the various regimes. At minimum fluidisation velocity, Umf, the structure of the bed is isostatic. When the gas velocity U is increased ...
DOI:
10.1016/j.powtec.2014.10.017

58. A DEM simulation of dry and wet particle flow behaviors in riser

Author:
Meng Wang; Weibing Zhu; Qiaoqun Sun; Xiaobin Zhang
Source:
Powder technology 2014 v.267 pp. 221-233
ISSN:
0032-5910
Subject:
equations; fluidized beds; friction; gases; liquids; powders
Abstract:
... In the present paper, the flow characteristics of dry and wet particles in circulating fluidized bed riser are simulated by using the Euler–Lagrange approach, in which the solid phase is modeled by the discrete element method (DEM) and the gas phase is solved by the Navier–Stokes equations. The forces acting on particles include contact force, friction force, van der Waals force, liquid bridge for ...
DOI:
10.1016/j.powtec.2014.07.026

59. A DFT analysis on the radical scavenging activity of oxygenated terpenoids present in the extract of the buds of Cleistocalyx operculatus

Author:
Thi Chinh Ngo; Duy Quang Dao; Minh Thong Nguyen; Pham Cam Nam
Source:
RSC advances 2017 v.7 no.63 pp. 39686-39698
ISSN:
2046-2069
Subject:
Lewis acids; Syzygium nervosum; antioxidant activity; buds; chemical bonding; electrons; ethanol; free radicals; gases; hardness; hydroxyl radicals; models; monoterpenoids; potential energy
Abstract:
... The antioxidant capacity of twenty-one oxygenated monoterpene and oxygenated desquiterpene compounds in the extract from Cleistocalyx operculatus has been computationally evaluated. Calculated by (RO)B3LYP/6-311++G(2df,2p)//B3LYP/6-311G(d,p) model chemistries, the thermochemical parameters, namely BDE, IE, PDE, PA and ETE in the gas phase, water and ethanol were determined. In addition, quantum de ...
DOI:
10.1039/c7ra04798c

60. A DFT study of (WO₃)₃ nanoclusters adsorption on defective MgO ultrathin films on Ag(001)

Author:
Hui Zhang; Jia Zhu; Zhenxing Fang; Xianglan Xu; Yongfan Zhang; Yuehua Fan
Source:
RSC advances 2017 v.7 no.85 pp. 54091-54099
ISSN:
2046-2069
Subject:
adsorption; chemical bonding; chemical reactions; density functional theory; energy; gases; magnesium oxide; nanoparticles; nanosilver; oxygen; scanning tunneling microscopy; silver; tungsten oxide
Abstract:
... The structures and electronic properties of (WO₃)₃ nanoclusters adsorption on defective MgO ultrathin films on Ag(001) have been investigated by means of density functional theory (DFT) calculations including dispersion interactions. Our results show that, after deposition, the oxygen vacancy on the defective MgO/Ag(001) films is healed by one terminal oxygen atom of the (WO₃)₃ clusters through fo ...
DOI:
10.1039/c7ra11025a

61. A DFT study of NO2 and SO2 gas-sensing properties of InX (X = Cl, Br and I) monolayers

Author:
Mingyu Zhao; Daoyu Zhang; Shuai Dong
Source:
Journal of materials science 2021 v.56 no.20 pp. 11828-11837
ISSN:
0022-2461
Subject:
density functional theory; gases; journals; materials science; mechanical stress
Abstract:
... Gas sensors have attracted much attentions due to their applications for alarming dangerous gases. It is important for a gas sensor to find out suitable sensing materials realizing its performance. Two-dimensional materials with high surface-to-volume ratios are ideal candidates acting as gas-sensing materials. Here, we report NO₂ and SO₂ gas-sensing properties of InX (X = Cl, Br, and I) monolayer ...
DOI:
10.1007/s10853-021-06047-1

62. A DFT study of the acid-catalyzed conversion of 2,5-dimethylfuran and ethylene to p-xylene

Author:
Nima Nikbin; Phuong T. Do; Stavros Caratzoulas; Raul F. Lobo; Paul J. Dauenhauer; Dionisios G. Vlachos
Source:
Journal of catalysis 2013 v.297 no. pp. 35-43
ISSN:
0021-9517
Subject:
Lewis acids; catalysts; ethylene; gases; lithium; prediction; temperature; xylene; zeolites
Abstract:
... We present a detailed mechanism for the conversion of DMF (2,5-dimethylfuran) and ethylene to p-xylene, obtained by gas-phase DFT electronic structure calculations. The conversion consists of Diels–Alder cycloaddition and subsequent dehydration of the cycloadduct, an oxa-norbornene derivative. We present the energetics of both the uncatalyzed and acid-catalyzed (Brønsted and Lewis) reactions. Even ...
DOI:
10.1016/j.jcat.2012.09.017

63. A DFT study of the origins of the stereoselectivity in the aldol reaction of bicyclic amino ketones in the presence of water

Author:
Ryszard Lazny; Artur Ratkiewicz; Aneta Nodzewska; Joanna Wysocka
Source:
Tetrahedron letters 2012 v.53 no.44 pp. 5871-5874
ISSN:
0040-4039
Subject:
benzaldehyde; chemical reactions; chemical structure; gases; ketones; solvents; thermodynamics; tropinone
Abstract:
... Experimental diastereoselectivities of the direct solvent-less (neat) aldol reactions of tropinone (8-methyl-8-azabicyclo[3.2.1]octan-3-one) and granatanone (pseudopelletierine, 9-methyl-9-azabicyclo[3.3.1]nonan-3-one) in the presence of catalytic amounts of water are most accurately reproduced by thermodynamic distributions of isomeric products calculated in the gas phase at the B3LYP/6-31g(d) le ...
DOI:
10.1016/j.tetlet.2012.08.070

64. A DFT-D study on the interaction between lactic acid and single-wall carbon nanotubes

Author:
Alireza Najafi Chermahini; Abbas Teimouri; Hossein Farrokhpour
Source:
RSC advances 2015 v.5 no.118 pp. 97724-97733
ISSN:
2046-2069
Subject:
adsorption; carbon nanotubes; density functional theory; energy; gases; lactic acid; moieties; optical isomerism; solvents; thermodynamics
Abstract:
... Density functional theory (DFT) was used to investigate the adsorption of lactic acid molecules on the surface of (4,4), (5,5), (6,6) and (7,7) single-walled carbon nanotubes (SWCNTs). A hybrid DFT method with the inclusion of dispersion correction was employed and the results compared to those obtained from the non-corrected DFT method. The energies and optimum distances for two different configu ...
DOI:
10.1039/c5ra19949b

65. A DOPO based reactive flame retardant constructed by multiple heteroaromatic groups and its application on epoxy resin: curing behavior, thermal degradation and flame retardancy

Author:
Qianqian Zhang; Shuang Yang; Jun Wang; Jianwen Cheng; Qiaoxin Zhang; Guoping Ding; Yefa Hu; Siqi Huo
Source:
Polymer degradation and stability 2019 v.167 pp. 10-20
ISSN:
0141-3910
Subject:
Fourier transform infrared spectroscopy; combustion; crosslinking; epoxides; fire hazard; flame retardants; free radicals; gases; glass transition temperature; heat; imidazole; mass spectrometry; nuclear magnetic resonance spectroscopy; oxygen; phosphorus; phosphorus content; stable isotopes; thermal degradation; thermal stability; thermogravimetry
Abstract:
... A high-efficiency flame retardant composed of phosphaphenanthrene, benzothiazole and imidazole groups (PBI) was synthesized and served as flame retardant co-curing agent to reduce the fire hazard of epoxy resin (EP). The chemical structure of PBI was characterized by Fourier transform infrared spectroscopy (FTIR), high-resolution mass spectroscopy (HR-MS), 1H and 31P nuclear magnetic resonance (NM ...
DOI:
10.1016/j.polymdegradstab.2019.06.020

66. A Diffusion-Equilibrium Method for Obtaining Soil Gases under Field Conditions

Author:
George S. Taylor; J. H. Abrahams
Source:
Soil Science Society of America journal 1953 v.17 no.3 pp. 201-206
ISSN:
0361-5995
Subject:
absorption; equations; gases; laboratory experimentation; mass flow; mixing; oxygen; partial pressure; soil air; soil depth; soil water content
Abstract:
... A soil gas sample obtained by mass flow of gases may not be representative of the point sampled because of mixing with gases from other soil depths or from the atmosphere. The authors have investigated a method which eliminates this error and which is based on the diffusion of gases between a point in the soil to a collection chamber via a tube tightly fitted in the soil. A physical analysis and l ...
DOI:
10.2136/sssaj1953.03615995001700030005x

67. A Dual-Membrane Airlift Reactor for Cyclohexanone Ammoximation over Titanium Silicalite-1

Author:
Chen Rizhi; Mao Honglin; Zhang Xiangrong; Xing Weihong; Fan Yiqun
Source:
Industrial & Engineering Chemistry Research 2014 v.53 no.15 pp. 6372-6379
ISSN:
1520-5045
Subject:
ammonia; bubbles; catalysts; ceramics; cyclohexanones; engineering; filtration; fouling; gases; solvents; titanium
Abstract:
... A novel dual-membrane airlift reactor with a ceramic outer-membrane as a reactant ammonia distributor and another ceramic inner-membrane as a catalyst separator was developed for the cyclohexanone ammoximation over titanium silicalite-1(TS-1) without the addition of extra solvent such as tert-butanol, resulting in no need of separation step for solvent. It was interesting to find that the introduc ...
DOI:
10.1021/ie500573d

68. A Dynamic Two-Dimensional System for Measuring Volatile Organic Compound Volatilization and Movement in Soils

Author:
S.E. Allaire; S.R. Yates; F.F. Ernst; J. Gan
Source:
Journal of environmental quality 2002 v.31 no.4 pp. 1079-1087
ISSN:
1537-2537
Subject:
bromine; emissions; fumigants; furrow irrigation; gas chromatography; gases; instrumentation; labor; mathematical models; pest control; sandy loam soils; soil injection; soil profiles; syringes; toxicity; volatile organic compounds; volatilization
Abstract:
... There is an important need to develop instrumentation that allows better understanding of atmospheric emission of toxic volatile compounds associated with soil management. For this purpose, chemical movement and distribution in the soil profile should be simultaneously monitored with its volatilization. A two-dimensional rectangular soil column was constructed and a dynamic sequential volatilizati ...
DOI:
10.2134/jeq2002.1079

69. A Facile N≡N Bond Cleavage by the Trinuclear Metal Center in Vanadium Carbide Cluster Anions V₃C₄–

Author:
Zi-Yu Li; Yao Li; Li-Hui Mou; Jiao-Jiao Chen; Qing-Yu Liu; Sheng-Gui He; Hui Chen
Source:
Journal of the American Chemical Society 2020 v.142 no.24 pp. 10747-10754
ISSN:
1520-5126
Subject:
adsorption; anions; carbon; cleavage (chemistry); dissociation; gases; image analysis; ligands; mass spectrometry; nitrogen; nitrogen fixation; vanadium
Abstract:
... Cleavage of the triple N≡N bond by metal clusters is of fundamental interest and practical importance in nitrogen fixation. Previous studies of N≡N bond cleavage by gas-phase metal clusters emphasized the importance of the dinuclear metal centers. Herein, the dissociative adsorption of N₂ and subsequent C–N coupling on trinuclear carbide cluster anions V₃C₄– under thermal collision conditions have ...
DOI:
10.1021/jacs.0c02021

70. A Fe₅C₂ nanocatalyst for the preferential synthesis of ethanol via dimethyl oxalate hydrogenation

Author:
Jia He; Yujun Zhao; Yue Wang; Junhu Wang; Jian Zheng; Hanlei Zhang; Guangwen Zhou; Chongmin Wang; Shengping Wang; Xinbin Ma
Source:
Chemical communications 2017 v.53 no.39 pp. 5376-5379
ISSN:
1364-548X
Subject:
acetates; catalysts; catalytic activity; ethanol; ethylene glycol; gases; hydrogenation; iron; nanomaterials; oxalates
Abstract:
... A Fe-based catalyst exhibits extremely high selectivity (89.6%) besides excellent catalytic activity in gas-phase dimethyl oxalate hydrogenation. The ethanol formation occurs via hydrogenation of methyl acetate instead of ethylene glycol over the active species Fe₅C₂. ...
DOI:
10.1039/c7cc01644a

71. A Film Boiling Study of Ethanol Pyrolysis

Author:
C. Thomas Avedisian; Wei-Chih Kuo; Wing Tsang; Adam Lowery
Source:
Industrial & engineering chemistry process design and development 2018 v.57 no.24 pp. 8334-8340
ISSN:
1520-5045
Subject:
acetaldehyde; boiling; carbon dioxide; carbon monoxide; chemical inhibitors; ethane; ethanol; ethyl acetate; ethylene; formaldehyde; gases; heat transfer; hydrogen; liquids; methane; process design; processing chemistry; pyrolysis; temperature
Abstract:
... This paper reports a study of ethanol pyrolysis (C₂H₅OH, EtOH) by film boiling at temperatures ranging from 600 to 1500 K. The reactor space is created in a self-assembled manner by first bringing EtOH to a boil on the surface of a horizontal tube submerged in a pool of EtOH and then increasing the power to the tube in steps to force transitioning the boiling regimes through nucleate boiling, the ...
DOI:
10.1021/acs.iecr.8b00770

72. A First-Principles Model of Fermi Resonance in the Alkyl CH Stretch Region: Application to Hydronaphthalenes, Indanes, and Cyclohexane

Author:
Sibert Edwin L.; Kidwell Nathanael M.; Zwier Timothy S.
Source:
Journal of physical chemistry 2014 v.118 no.28 pp. 8236-8245
ISSN:
1520-5207
Subject:
chemical elements; cyclohexanes; free radicals; gases; infrared spectroscopy; models; physical chemistry; prediction
Abstract:
... The infrared (IR) spectroscopy of the alkyl CH stretch region (2750–3000 cm–¹) of a series of bicyclic hydrocarbons and free radicals has been studied under supersonic expansion cooling in the gas phase, and compared with a theoretical model that describes the local mode stretch–bend Fermi resonance interactions. The double resonance method of fluorescence-dip infrared (FDIR) spectroscopy was used ...
DOI:
10.1021/jp5014048

73. A Fragile Zwitterionic Phosphasilene as a Transfer Agent of the Elusive Parent Phosphinidene (:PH)

Author:
Hansen Kerstin; Szilvási Tibor; Blom Burgert; Inoue Shigeyoshi; Epping Jan; Driess Matthias
Source:
Journal of the American Chemical Society 2013 v.135 no.32 pp. 11795-11798
ISSN:
1520-5126
Subject:
ambient temperature; dissociation; gases; phosphorus; zwitterions
Abstract:
... The simplest parent phosphinidene, :PH (1), has been observed only in the gas phase or low temperature matrices and has escaped rigorous characterization because of its high reactivity. Its liberation and transfer to an unsaturated organic molecule in solution has now been accomplished by taking advantage of the facile homolytic bond cleavage of the fragile SiP bond of the first zwitterionic phos ...
DOI:
10.1021/ja4072699

74. A Frontier Orbital Study with ab Initio Molecular Dynamics of the Effects of Solvation on Chemical Reactivity: Solvent-Induced Orbital Control in FeO-Activated Hydroxylation Reactions

Author:
Bernasconi Leonardo; Baerends Evert Jan
Source:
Journal of the American Chemical Society 2013 v.135 no.24 pp. 8857-8867
ISSN:
1520-5126
Subject:
EDTA (chelating agent); Gibbs free energy; aqueous solutions; energy; ferrous oxide; gases; hydroxylation; ligands; methane; molecular dynamics; screening; solutes
Abstract:
... Solvation effects on chemical reactivity are often rationalized using electrostatic considerations: the reduced stabilization of the transition state results in higher reaction barriers and lower reactivity in solution. We demonstrate that the effect of solvation on the relative energies of the frontier orbitals is equally important and may even reverse the trend expected from purely electrostatic ...
DOI:
10.1021/ja311144d

75. A Fully Size-Resolved Perspective on the Crystallization of Water Clusters

Author:
Christoph C. Pradzynski; Richard M. Forck; Thomas Zeuch; Petr Slavíček; Udo Buck
Source:
Science 2012 v.337 no.6101 pp. 1529-1532
ISSN:
0036-8075
Subject:
absorption; crystallization; crystals; gases; ice; infrared spectroscopy; water
Abstract:
... Minimal Ice Water clusters comprising fewer than 100 molecules have long been studied in gas phase to model the more complex structures of ice and liquid water. At some stage, as clusters grow larger, they effectively become tiny crystals of ice, but it has been hard to pinpoint precisely where in the range between 100 and 1000 molecules the formal transition takes place. Pradzynski et al. (p. 152 ...
DOI:
10.1126/science.1225468

76. A GIS-based approach: Influence of the ventilation layout to the environmental conditions in an underground mine

Author:
Marc Bascompta; Ana María Castañón; Lluís Sanmiquel; Josep Oliva
Source:
Journal of environmental management 2016 v.182 pp. 525-530
ISSN:
0301-4797
Subject:
air flow; carbon dioxide; carbon monoxide; case studies; environmental factors; equipment; gases; geographic information systems; nitrogen oxides; pollutants; temperature; ventilation systems; working conditions
Abstract:
... Gases such as CO, CO2 or NOx are constantly generated by the equipment in any underground mine and the ventilation layout can play an important role in keeping low concentrations in the working faces. Hence, a method able to control the workplace environment is crucial. This paper proposes a geographical information system (GIS) for such goal. The system created provides the necessary tools to man ...
DOI:
10.1016/j.jenvman.2016.08.013

77. A Gas Diffusivity Model Based on Air-, Solid-, and Water-Phase Resistance in Variably Saturated Soil

Author:
Anne Thorbjørn; Per Moldrup; Helle Blendstrup; Toshiko Komatsu; Dennis E. Rolston
Source:
Vadose zone journal 2008 v.7 no.4 pp. 1276-1286
ISSN:
1539-1663
Subject:
gases; simulation models; saturated conditions; porosity; diffusivity; vadose zone
Abstract:
... Gas diffusion in soil is governed by the gas diffusion coefficient (D ₚ) and its variation with air-filled porosity (ε). Accurate or an upper-limit (risk assessment standpoint) prediction of D ₚ(ε) is essential when carrying out gas transport and fate calculations. We developed a D ₚ(ε) model for relatively unstructured soil separating the individual resistance of soil air, solids, and moisture to ...
DOI:
10.2136/vzj2008.0023

78. A Gaseous Metal Disk Around a White Dwarf

Author:
Gänsicke, B.T.; Marsh, T.R.; Southworth, J.; Rebassa-Mansergas, A.
Source:
Science 2006 v.314 no.5807 pp. 1908-1910
ISSN:
0036-8075
Subject:
dynamic models; gases; metals; physical phenomena
Abstract:
... The destiny of planetary systems through the late evolution of their host stars is very uncertain. We report a metal-rich gas disk around a moderately hot and young white dwarf. A dynamical model of the double-peaked emission lines constrains the outer disk radius to just 1.2 solar radii. The likely origin of the disk is a tidally disrupted asteroid, which has been destabilized from its initial or ...
DOI:
10.1126/science.1135033

79. A Generalized Law of Corresponding States for the Physisorption of Classical Gases with Cooperative Adsorbate–Adsorbate Interactions

Author:
Murialdo Maxwell; Stadie Nicholas P.; Ahn Channing C.; Fultz Brent
Source:
The Journal of Physical Chemistry C 2016 v.120 no.22 pp. 11847-11853
ISSN:
1932-7455
Subject:
adsorption; carbon; gases; models
Abstract:
... The Law of Corresponding States for classical gases is well established. Recent attempts at developing an analogous Law of Corresponding States for gas physisorption, however, have had limited success, in part due to the omission of relevant adsorption considerations such as the adsorbate volume and cooperative adsorbate–adsorbate interactions. In this work, we modify a prior Law of Corresponding ...
DOI:
10.1021/acs.jpcc.6b00289

80. A Generic Machine Learning Algorithm for the Prediction of Gas Adsorption in Nanoporous Materials

Author:
George S. Fanourgakis; Konstantinos Gkagkas; Emmanuel Tylianakis; George Froudakis
Source:
Journal of physical chemistry 2020 v.124 no.13 pp. 7117-7126
ISSN:
1932-7455
Subject:
adsorption; algorithms; artificial intelligence; carbon dioxide; data collection; databases; gases; hydrogen; hydrogen sulfide; methane; nanopores; prediction; screening; thermodynamics; van der Waals forces
Abstract:
... In the present study, we propose a new set of descriptors, appropriate for machine learning (ML) methods, aiming to predict accurately the gas adsorption capacities of nanoporous materials. The present work focuses on systems with nonnegligible electrostatic interactions between the materials’ framework and the guest gas. For that, the CO₂, H₂, and H₂S gases are examined. The present approach is a ...
DOI:
10.1021/acs.jpcc.9b10766

81. A Giant Planet Imaged in the Disk of the Young Star β Pictoris

Author:
Lagrange, A.-M.; Bonnefoy, M.; Chauvin, G.; Apai, D.; Ehrenreich, D.; Boccaletti, A.; Gratadour, D.; Rouan, D.; Mouillet, D.; Lacour, S.; Kasper, M.
Source:
Science 2010 v.329 no.5987 pp. 57-59
ISSN:
0036-8075
Subject:
Earth system science; gases; image analysis
Abstract:
... Here, we show that the approximately 10-million-year-old β Pictoris system hosts a massive giant planet, β Pictoris b, located 8 to 15 astronomical units from the star. This result confirms that gas giant planets form rapidly within disks and validates the use of disk structures as fingerprints of embedded planets. Among the few planets already imaged, β Pictoris b is the closest to its parent sta ...
DOI:
10.1126/science.1187187

82. A Grand Canonical Monte Carlo Study of the N2, CO, and Mixed N2–CO Clathrate Hydrates

Author:
Antoine Patt; Jean-Marc Simon; Sylvain Picaud; J. Marcos Salazar
Source:
Journal of physical chemistry 2018 v.122 no.32 pp. 18432-18444
ISSN:
1932-7455
Subject:
Monte Carlo method; carbon monoxide; encapsulation; gases; nitrogen; physical chemistry; temperature
Abstract:
... In this paper we report the use of Grand Canonical Monte Carlo (GCMC) simulations to characterize the competitive trapping of CO and N₂ molecules into clathrates, for various gas compositions in the temperature range from 50 to 150 K. The simulations evidence a preferential trapping of CO with respect to N₂. This leads to the formation of clathrates that are preferentially filled with CO at equili ...
DOI:
10.1021/acs.jpcc.8b03657

83. A G₄·K⁺ hydrogel made from 5′-hydrazinoguanosine for remediation of α,β-unsaturated carbonyls

Author:
Songjun Xiao; Jeffery T. Davis
Source:
Chemical communications 2018 v.54 no.80 pp. 11300-11303
ISSN:
1364-548X
Subject:
acrolein; chemical reactions; gases; hydrogels; potassium; potassium chloride; remediation; toxicity
Abstract:
... A G₄·K⁺ hydrogel made from 5′-hydrazinoguanosine and KCl reacts with α,β-unsaturated carbonyls of different electrophilicities (acrolein, methyl vinyl ketone and methyl acrylate) in water and the gas phase to form cyclic adducts. This aza-Michael addition/cyclization domino reaction by the 5′-hydrazino G₄·K⁺ hydrogel has promise for environmental remediation of toxic α,β-unsaturated carbonyls from ...
DOI:
10.1039/c8cc07228k

84. A Highly Proton-Conductive 3D Ionic Cadmium–Organic Framework for Ammonia and Amines Impedance Sensing

Author:
Ruilan Liu; Yaru Liu; Shihang Yu; Chenglin Yang; Zifeng Li; Gang Li
Source:
ACS applied materials & interfaces 2018 v.11 no.1 pp. 1713-1722
ISSN:
1944-8252
Subject:
ambient temperature; ammonia; cadmium; carboxylic acids; coordination polymers; dimethylamine; gases; methylamine; nitrates; relative humidity; sodium; trimethylamine
Abstract:
... Lately, the progressive study of metal–organic frameworks (MOFs) for the detection of ammonia and amines has made infusive achievements. Nevertheless, the investigation of proton-conductive MOFs used to detect the low concentrations of ammonia and amine gases at different relative humidities (RHs) at room temperature is relatively restricted. Herein, by solvothermal reaction of Cd(NO₃)₂ with 2-met ...
DOI:
10.1021/acsami.8b18891

85. A Highly Rigid and Conjugated Microporous Polymer Membrane for Solvent Permeation and Biofuel Purification: A Molecular Simulation Study

Author:
Jie Liu; Wan Wei; Jianwen Jiang
Source:
ACS sustainable chemistry & engineering 2020 v.8 no.7 pp. 2892-2900
ISSN:
2168-0485
Subject:
acetone; acetonitrile; adsorption; biofuels; ethanol; gases; hydrophobicity; methanol; micropores; molecular dynamics; molecular weight; organic matter; permeability; polymers; porous media; solvents; viscosity
Abstract:
... With rigid π-conjugated skeletons and permanent micropores, conjugated microporous polymers (CMPs) have attracted increasing interest. Nevertheless, most current studies for CMPs are largely focused on the adsorption of gases and organic molecules. Herein, a molecular simulation study is reported to investigate a CMP membrane (p-CMP) for solvent permeation and biofuel (represented by ethanol/water ...
DOI:
10.1021/acssuschemeng.9b07207

86. A Hydrodynamic Comparison of Solution and Gas Phase Proteins and Their Complexes

Author:
Hewitt Dominic; Marklund Erik; Scott David J.; Robinson Carol V.; Borysik Antoni J.
Source:
Journal of physical chemistry 2014 v.118 no.29 pp. 8489-8495
ISSN:
1520-5207
Subject:
gases; hydrodynamics; mass spectrometry; protein structure; proteins
Abstract:
... The extent to which protein structures are preserved on transfer from solution to gas phase is a central question for native mass spectrometry. Here we compare the collision cross sections (Ω) of a wide range of different proteins and protein complexes (15–500 kDa) with their corresponding Stokes radii (RS). Using these methods, we find that Ω and RS are well correlated, implying overall preservat ...
DOI:
10.1021/jp501950d

87. A Hyperbaric Chamber for Observation of Cell Cultures at Pressure

Author:
J. Jenssen; G. Bolstad; T. Syversen
Source:
ATLA. Alternatives to laboratory animals v.14 no.3 pp. 158-160
ISSN:
0261-1929
Subject:
animal use alternatives; cell culture; pressure; gases; toxicity; pharmacology
Abstract:
... A chamber system has been constructed for the study of hydrostatic and gas pressure effects on cells in culture. The chamber is fitted with a phase contrast light microscope allowing direct observation and video recording of the cells at pressure. Cell differentiation over a period of hours to days may thus be recorded and taped from as many as 24 cell samples in the same experiment, using a time- ...
DOI:
10.1177/026119298701400310

88. A Laboratory Technique for Releasing and Measuring Denitrification Products Trapped in Soil

Author:
L. S. Holt; C. B. Christianson; E. R. Austin; J. C. Katyal
Source:
Soil Science Society of America journal 1988 v.52 no.5 pp. 1510-1511
ISSN:
0361-5995
Subject:
denitrification; gases; headspace analysis; laboratory techniques; nitrogen; nitrogen fertilizers; soil; stable isotopes
Abstract:
... Several laboratory denitrification studies have shown an incomplete ¹⁵N balance at their conclusion. This incomplete ¹⁵N balance could be attributed to trapped gaseous products of denitrification within the soil. Incubation trials were designed to determine whether a complete ¹⁵N balance could be achieved if these trapped gases were released and included in the ¹⁵N balance. At the end of a prelimi ...
DOI:
10.2136/sssaj1988.03615995005200050057x

89. A Lagrangian-Eulerian hybrid model for the simulation of poly-disperse fluidized beds: Application to industrial-scale olefin polymerization

Author:
Simon Schneiderbauer; Stefan Pirker; Stefan Puttinger; Pablo Aguayo; Vasileios Touloupidis; Alberto Martínez Joaristi
Source:
Powder technology 2017 v.316 pp. 697-710
ISSN:
0032-5910
Subject:
catalysts; crystal structure; energy; fluidized beds; gases; heat; hydrodynamics; models; olefin; particle size distribution; polymerization; polymers; powders; solubility; temperature
Abstract:
... We present a generalization of the Lagrangian-Eulerian hybrid model for the numerical assessment of poly-disperse gas-solid flows (Schneiderbauer et al., Pow. Tech., 2016) to olefin polymerization fluidized beds. The main idea of such a modeling strategy is to use a combination of a Lagrangian discrete phase model (DPM) and a coarse-grained two-fluid model (TFM) to take advantage of the benefits o ...
DOI:
10.1016/j.powtec.2016.12.063

90. A Linear Model for the Estimation of Fuel Consumption and the Impact Evaluation of Advanced Driving Assistance Systems

Author:
Gennaro Nicola Bifulco; Francesco Galante; Luigi Pariota; Maria Russo Spena
Source:
Sustainability 2015 v.7 no.10 pp. 14326-14343
ISSN:
2071-1050
Subject:
energy use and consumption; environmental impact; gases; industry; linear models; traffic
Abstract:
... Reduction of the environmental impact of cars represents one of the biggest transport industry challenges. Beyond more efficient engines, a promising approach is to use eco-driving technologies that help drivers achieve lower fuel consumption and emission levels. In this study, a real-time microscopic fuel consumption model was developed. It was designed to be integrated into simulation platforms ...
DOI:
10.3390/su71014326

91. A Lithium Amide Protected Against Protonation in the Gas Phase: Unexpected Effect of LiCl

Author:
Lesage Denis; Barozzino-Consiglio Gabriella; Duwald Romain; Fressigné Catherine; Harrison-Marchand Anne; Faull Kym F.; Maddaluno Jacques; Gimbert Yves
Source:
Journal of organic chemistry 2015 v.80 no.12 pp. 6441-6446
ISSN:
1520-6904
Subject:
chemical reactions; chemical structure; chlorine; electrospray ionization mass spectrometry; gases; lithium; lithium chloride; nitrogen; organic chemistry; organic compounds; protons
Abstract:
... In cold THF and in the presence of LiCl, a lithium pyrrolidinylamide forms a 1:1 mixed aggregate, which is observed directly by ESI-MS. Gas-phase protonation of this species leads to selective transfer of H⁺ to the chlorine, suggesting that LiCl shields the amide nitrogen and prevents its direct protonation. ...
DOI:
10.1021/acs.joc.5b00875

92. A MILP model concerning the optimisation of penalty factors for the short-term distribution of byproduct gases produced in the iron and steel making process

Author:
Xiancong Zhao; Hao Bai; Xin Lu; Qi Shi; Jiehai Han
Source:
Applied energy 2015 v.148 pp. 142-158
ISSN:
0306-2619
Subject:
boilers; byproducts; carbon dioxide; case studies; electricity costs; energy; energy conservation; gases; industry; iron; linear programming; models; operating costs; planning; statistical analysis; steel
Abstract:
... In integrated steel works, byproduct gases are generated in the iron and steel making process, which accounts for approximately 30% of the total energy involved. The efficient utilisation of these gases is significant for energy saving and CO2 reduction in the iron and steel industry. In this paper, a mixed integer linear programming (MILP) model was proposed to optimise the byproduct gas manageme ...
DOI:
10.1016/j.apenergy.2015.03.046

93. A Management Strategy for Multiple Ecosystem Services in Boreal Forests

Author:
Stig-Olof Holm
Source:
Journal of sustainable forestry 2015 v.34 no.4 pp. 358-379
ISSN:
1540-756X
Subject:
biodiversity; boreal forests; ecosystem services; forestry; gases; landscapes; logging; models; plantations; reindeer; sustainable forestry; trees; wood
Abstract:
... A change of the forestry management approach where semi-natural forests are re-created after logging instead of tree plantations will contribute to a sustainable forestry. Such a change will increase resilience to damages on trees, thus contributing to a more reliable supply of wood, improve reindeer husbandry, and reduce climate-driving gases. Furthermore, re-creation of semi-natural forests will ...
DOI:
10.1080/10549811.2015.1009633

94. A Mechanism for Anomalous Decline in Radon Precursory to an Earthquake

Author:
Kuo, M.C. Tom; Fan, K.; Kuochen, H.; Chen, W.
Source:
Ground water 2006 v.44 no.5 pp. 642-647
ISSN:
0017-467X
Subject:
case studies; cracking; earthquakes; gases; groundwater; labeling techniques; mudstone; porosity; radon; sandstone; springs (water); temperature; Taiwan
Abstract:
... Mechanisms for interpreting anomalous decreases in radon in ground water prior to earthquakes are examined with the help of a case study to show that radon potentially is a sensitive tracer of strain changes in the crust preceding an earthquake. The 2003 Chengkung earthquake of magnitude (M) 6.8 on December 10, 2003, was the strongest earthquake near the Chengkung area in eastern Taiwan since 1951 ...
DOI:
10.1111/j.1745-6584.2006.00219.x
PubMed:
16961485

95. A Mechanistic Study of Dehydrogenation of Propane over Vanadia–Titania Catalysts

Author:
Vasily V. Kaichev; Yuriy A. Chesalov; Andrey A. Saraev; Anna M. Tsapina
Source:
Journal of physical chemistry 2019 v.123 no.32 pp. 19668-19680
ISSN:
1932-7455
Subject:
Fourier transform infrared spectroscopy; X-ray photoelectron spectroscopy; acetates; acetone; active sites; carbon dioxide; carbon monoxide; carbonates; catalysts; cations; chemical bonding; dehydrogenation; formates; gases; nanoparticles; oxidation; oxygen; propane; propylene; titanium dioxide; vanadium; vanadyl ions
Abstract:
... The oxidative and non-oxidative dehydrogenation of propane over a monolayer V₂O₅/TiO₂ catalyst was examined using in situ Fourier transform infrared spectroscopy and pseudo in situ X-ray photoelectron spectroscopy (XPS). It was found that the freshly calcined catalyst contains vanadium in the V⁵⁺ state; however, its treatment in the propane flow leads to the reduction of V⁵⁺ to V³⁺. Simultaneously ...
DOI:
10.1021/acs.jpcc.9b04991

96. A Method to Determine Soil-Entrapped Denitrification Products in Submerged Soils

Author:
J. C. Katyal; L. S. Holt; A. M. Gadalla
Source:
Soil Science Society of America journal 1989 v.53 no.1 pp. 296-297
ISSN:
0361-5995
Subject:
bags; denitrification; gases; headspace analysis; isotope labeling; nitrogen; polyesters; potassium nitrate; silt loam soils; stable isotopes
Abstract:
... To measure the contribution of soil-entrapped gases to denitrification in submerged soils, a soil-filled cylindrical bag (7 cm in height by 5-cm diam) made from stiff polyester cloth net was positioned in the center of potted Crowley silt loam soil. Denitrification of ¹⁵N-labeled KNO₃ (14.85 atom % excess, applied at 100 kg N ha⁻¹) was complete in 16 d after fertilization; 71% of the KNO₃ was deni ...
DOI:
10.2136/sssaj1989.03615995005300010054x

97. A Modified Drift Tube Ion Mobility-Mass Spectrometer for Charge-Multiplexed Collision-Induced Unfolding

Author:
Daniel D. Vallejo; Daniel A. Polasky; Ruwan T. Kurulugama; Joseph D. Eschweiler; John C. Fjeldsted; Brandon T. Ruotolo
Source:
Analytical chemistry 2019 v.91 no.13 pp. 8137-8146
ISSN:
1520-6882
Subject:
amino acid sequences; antibodies; biopharmaceuticals; data collection; dissociation; electric potential difference; gases; ions; post-translational modification; protein unfolding; proteins; spectrometers
Abstract:
... Collision-induced unfolding (CIU) of protein ions and their noncovalent complexes offers relatively rapid access to a rich portfolio of biophysical information, without the need to tag or purify proteins prior to analysis. Such assays have been characterized extensively for a range of therapeutic proteins, proving exquisitely sensitive to alterations in protein sequence, structure, and post-transl ...
DOI:
10.1021/acs.analchem.9b00427

98. A Modified Method for the In Situ Measurement of Soil Gas Diffusivity

Author:
Andreas Schwen; Jürgen Böttcher; Carolin von der Heide; Tim Fandré; Markus Deurer; Wilhelmus H.M. Duijnisveld
Source:
Soil Science Society of America journal 2011 v.75 no.3 pp. 813-821
ISSN:
0361-5995
Subject:
diffusivity; gases; loam soils; models; nitrous oxide; sand; soil air; soil heterogeneity; soil water; sulfur hexafluoride
Abstract:
... Gas diffusion coefficients are of importance for the calculation of gas fluxes in soils. Since many aspects of soil gas fluxes are affected by scale variability of soil properties, diffusion coefficients should be measured in situ and preferably for a large volume. In the present study, we modified the method of McIntyre and Philip. Gas diffusion through a laterally confined soil volume from a gas ...
DOI:
10.2136/sssaj2010.0272

99. A Molecular Simulation Study of Carbon Dioxide Uptake by a Deep Eutectic Solvent Confined in Slit Nanopores

Author:
Shen Yan; Hung Francisco R.
Source:
The Journal of Physical Chemistry C 2017 v.121 no.44 pp. 24562-24575
ISSN:
1932-7455
Subject:
carbon dioxide; chlorides; choline; diffusivity; ethylene glycol; gases; graphene; ionic liquids; liquids; molecular dynamics; nanopores; simulation models
Abstract:
... Molecular dynamics simulations were performed to study the behavior of CO₂ in varying amounts of a common deep eutectic solvent (DES), choline chloride and ethylene glycol (termed ethaline), confined in slit-like pores of width H = 5.2 nm with graphite or rutile walls at T = 318 K. In the absence of DES, CO₂ adsorbs to the pore walls, but increasing amounts of ethaline inside the pores quickly dis ...
DOI:
10.1021/acs.jpcc.7b07315

100. A Moving Window Formulation for Recursive Bayesian State Estimation of Systems with Irregularly Sampled and Variable Delays in Measurements

Author:
Bavdekar Vinay A.; Prakash Jagadeesan; Patwardhan Sachin C.; Shah Sirish L.
Source:
Industrial & Engineering Chemistry Research 2014 v.53 no.35 pp. 13750-13763
ISSN:
1520-5045
Subject:
algorithms; batch systems; case studies; engineering; gases
Abstract:
... The time delay involved between sampling and obtaining measurements of certain quality variables is a common scenario in various process applications. Further, this delay is not fixed and can vary for various reasons. Moreover, certain measurements may be sampled at irregular time intervals. The state estimation algorithms available in the literature have been developed for the scenario where the ...
DOI:
10.1021/ie5009585