Read by QxMD icon Read

Gas Hydrate

Erik Barwa, Milan Oncak, Tobias F Pascher, Thomas Taxer, Christian van der Linde, Martin K Beyer
Hydrated singly charged metal ions doped with carbon dioxide, Mg2+(CO2)-(H2O)n, in the gas phase are valuable model systems for the electrochemical activation of CO2. Here, we study these systems by Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry combined with ab initio calculations. We show that the exchange reaction of CO2 with O2 proceeds fast with bare Mg+(CO2), with a rate coefficient kabs = 1.2×10-10 cm3 s-1, while hydrated species exhibit a lower rate in the range of kabs = 1...
December 5, 2018: Journal of Physical Chemistry. A
Kyle Wm Hall, Zhengcai Zhang, Christian James Burnham, Guang-Jun Guo, Sheelagh Carpendale, Niall Joseph English, Peter G Kusalik
The broad scientific and technological importance of crystallization has led to significant research probing and rationalizing crystal nucleation processes. Previous work has generally neglected the possibility of the molecular-level dynamics of individual crystal nuclei coupling to local structures. However, recent experimental work has conjectured that this can occur. Therefore, to address a deficiency in scientific understanding of crystallization, we have probed the nucleation of prototypical single and multi-component crystals (specifically, ice and mixed gas hydrates)...
November 28, 2018: Journal of Physical Chemistry Letters
Meng-Ting Sun, Zhi-Man Yang, Xiao-Lei Fan, Fei Wang, Rong-Bo Guo, Dong-Yan Xu
Methane is a greenhouse gas with significant global warming potential. The methane-oxidizing bacteria (MOB) immobilized on biocarrier could perform effectively and environmentally in methane elimination. To further improve the efficiencies of MOB immobilization and methane elimination, the surface biocompatibility of biocarrier needs to be improved. In this work, the oil shale semicoke (SC) was chemically modified by sodium p-styrenesulfonate hydrate (SS) and 2-(methacryloyloxy)ethyltrimethylammonium chloride (DMC) to promote surface hydrophilicity and positive charge, respectively...
November 22, 2018: Science of the Total Environment
Selina Baldauf, Mónica Ladrón de Guevara, Fernando T Maestre, Britta Tietjen
Background: Biocrusts, communities dominated by mosses, lichens, cyanobacteria, and other microorganisms, largely affect the carbon cycle of drylands. As poikilohydric organisms, their activity time is often limited to short hydration events. The photosynthetic and respiratory response of biocrusts to hydration events is not only determined by the overall amount of available water, but also by the frequency and size of individual rainfall pulses. Methods: We experimentally assessed the carbon exchange of a biocrust community dominated by the lichen Diploschistes diacapsis in central Spain...
2018: PeerJ
Mit P Patel, Ali Ahmed, Tharini Gunapalan, Sean E Hesselbacher
Diabetic ketoacidosis (DKA) is a severe and too-common complication of uncontrolled diabetes mellitus. Acidosis is one of the fundamental disruptions stemming from the disease process, the complications of which are potentially lethal. Hydration and insulin administration have been the cornerstones of DKA therapy; however, adjunctive treatments such as the use of sodium bicarbonate and protocols that include serial monitoring with blood gas analysis have been much more controversial. There is substantial literature available regarding the use of exogenous sodium bicarbonate in mild to moderately severe acidosis; the bulk of the data argue against significant benefit in important clinical outcomes and suggest possible adverse effects with the use of bicarbonate...
November 15, 2018: World Journal of Diabetes
Ajay Muralidharan, Lawrence R Pratt, Mangesh I Chaudhari, Susan B Rempe
Accurate predictions of the hydration free energy for anions typically has been more challenging than for cations. Hydrogen bond donation to the anion in hydrated clusters such as F(H2O)n- can lead to delicate structures. Consequently, the energy landscape contains many local minima, even for small clusters, and these minima present a challenge for computational optimization. Utilization of cluster experimental results for the free energies of gas phase clusters shows that, even though anharmonic effects are interesting, they need not be of troublesome magnitudes for careful applications of quasi-chemical theory to ion hydration...
November 26, 2018: Journal of Physical Chemistry. A
Nasibeh Hajilary, Mashallah Rezakazemi
The gas sweetening unit of phase 2 and 3 in South Pars Gas Field (Asalouyeh, Iran) was first simulated to investigate the effect of mono ethylene glycol (MEG) in the amine loop. MEG is commonly injected into the system to avoid hydrate formation while a few amounts of MEG is usually transferred to amine gas sweetening plant. This paper aims to address the points where MEG has negative effects on gas sweetening process and what the practical ways to reduce its effect are. The results showed that in the presence of 25% of MEG in amine loop, H2 S absorption from the sour gas was increased from 1...
November 23, 2018: Chemistry Central Journal
Fei Zhang, Zhou Yu, Adam J Rondinone, Jingsong Huang, Bobby G Sumpter, Rui Qiao
The adsorption of gas molecules at electrode-electrolyte interfaces is an important step in their electrochemical reactions. Using molecular dynamics simulations, we investigate the adsorption of dissolved N2 in the electrical double layers (EDLs) of an aqueous electrolyte near planar and 1-nm-radius spherical carbon electrodes. The adsorption of N2 is found to be overall enriched near neutral electrodes regardless of their surface curvature, although it can be locally enriched or depleted depending on the distance from the electrode surface...
November 9, 2018: Langmuir: the ACS Journal of Surfaces and Colloids
Avinash V Palodkar, Amiya K Jana
Amount of natural gas contained in the gas hydrate accumulations is twice that of all fossil fuel reserves currently available worldwide. The conventional oil and gas recovery technologies are not really suitable to gas hydrates because of their serious repercussions on geo-mechanical stability and seabed ecosystem. To address this challenge, the concept of methane-carbon dioxide (CH4 -CO2 ) swapping has appeared. It has the potential in achieving safe and efficient recovery of natural gas, and sequestration of CO2 ...
November 8, 2018: Scientific Reports
Hongtao Liu
As a typical organic solid waste, sludge plays an important role in contributing to greenhouse gas (GHG) emissions resulted by its treatment and disposal. As a temporary and emergent treatment measurement, sludge lime stabilization is regionally adopted in most sludge generated units in China. In present case, sludge lime stabilization system in China was productive of total GHG emissions, including indirect and direct emissions during lime stabilization and carbon reduction owing to lime synthesis and consumption, were first quantified respectively...
November 8, 2018: Scientific Reports
Zhengfei Chen, Yuto Tonouchi, Kazuhiko Matsumoto, Masayuki Saimura, Rob Atkin, Takashi Nagata, Masato Katahira, Rika Hagiwara
Truly naked fluoride exists only in the gas phase. Fluoride can be stabilized by a complexing agent and an organic cation, resulting in anhydrous or dehydrated fluoride which is "partially naked." This partially naked fluoride enables fluorination reactions at much lower temperatures than hydrated fluorides. Here we show a simple method for preparing fluoride-based solvate ionic liquids (SILs) by mixing 1-alkyl-3-methylimidazolium (1-ethyl-3-methylimidazolium or 1-butyl-3-methylimidazolium) bromide, silver fluoride (AgF), and EG (1:1:1 in molar ratio) in dry methanol...
November 15, 2018: Journal of Physical Chemistry Letters
Luis Miguel Senzano, Denis Vieira Andrade
Terrestrial anurans often experience fluctuations in body temperature and hydration state, which are known to influence evaporative water loss through the skin (EWLSkin ) and lungs (EWLResp ). These effects arises from associated changes in skin permeability, metabolism and lung ventilation. Herein, we determined the rates of EWLSkin and EWLResp in the terrestrial toad, Rhinella schneideri , at different temperatures and hydration states. We measured oxygen uptake rates to verify whether alterations in the partitioning between EWLSkin and EWLResp were associated to metabolic induced changes in pulmonary gas exchange...
November 1, 2018: Journal of Experimental Biology
Nikolaos I Papadimitriou, Ioannis N Tsimpanogiannis, Ioannis G Economou, Athanassios K Stubos
The current study employs Grand Canonical Monte Carlo simulations in order to calculate the process efficiency of separating CH4 + CO2 gas mixtures by utilizing structure sI clathrate hydrates. The temperature and pressure conditions examined in the current study resemble those used in industry. The simulation results are compared with experimental measurements and very good agreement is found. In addition, hydrate cage occupancies are compared with experimental measurements and calculations using a commercial simulator...
November 14, 2018: Physical Chemistry Chemical Physics: PCCP
Baojian Wang, Xu Mao, Jianwei Zhu
Objective To study the protective effect of β-aescin on lipopolysaccharide (LPS) induced-acute lung injury (LPS-ALI) and to explore the underlying mechanism. Methods Sixty male C57BL/6 mice were randomly divided into four groups including normal control group, β-aescin-treated group, LPS-ALI group, LPS-ALI combined with β-aescin-treated group, with 15 mice in each group. For LPS-ALI group, the mice were intraperitoneally injected with chloral hydrate and 10 mg/kg of LPS was then injected into the lungs through oropharyngeal intubation...
July 2018: Xi Bao Yu Fen Zi Mian Yi Xue za Zhi, Chinese Journal of Cellular and Molecular Immunology
Getachew Kebede, Pavlin D Mitev, Peter Broqvist, Anders Eriksson, Kersti Hermansson
Crystalline ionic hydrates constitute a powerful and versatile resource for benchmarking theoretical methods with respect to their ability to model bound water molecules in environments where both hydrogen bonds and ion-water interactions are present. 50 structurally different "in-crystal" water molecules, and close to 100 non-equivalent O-H∙∙∙O hydrogen bonds are in focus and we examine how twelve well known DFT functionals, with or without dispersion treatments, manage to reproduce results from high-quality diffraction and spectroscopic investigations in the literature...
October 31, 2018: Journal of Chemical Theory and Computation
Christine Scoffoni, Caetano Albuquerque, Herve Cochard, Thomas N Buckley, Leila R Fletcher, Marissa A Caringella, Megan K Bartlett, Craig Brodersen, Steven Jansen, Andrew J McElrone, Lawren Sack
The influence of the dynamics of leaf hydraulic conductance (Kleaf) diurnally and during dehydration on stomatal conductance and photosynthesis remains unclear. Using the model species Arabidopsis thaliana (ecotype Col-0)., we applied a multi-tiered approach including physiological measurements, high-resolution X-ray micro-computed tomography, and modelling at a range of scales to characterize: (1) Kleaf decline during dehydration; (2) its basis in the hydraulic conductances of leaf xylem (Kx) and outside-xylem pathways (Kox); (3) the dependence of its dynamics on irradiance; (4) its impact on diurnal patterns of stomatal conductance and photosynthetic rate; and (5) its influence on gas exchange and survival under simulated drought regimes...
October 26, 2018: Plant Physiology
Jens Vive Kildgaard, Kurt V Mikkelsen, Merete Bilde, Jonas Elm
Using computational methods, we study the gas phase hydration of three different atmospherically relevant organic acids with up to 10 water molecules. We study a dicarboxylic acid (pinic acid) and a tricarboxylic acid (3-methyl-1,2,3-butanetricarboxylic acid (mbtca)) that are both identified as products from α-pinene oxidation reactions. We also study a 2-oxohexanediperoxy acid (ohdpa) that has been identified as a product from cyclohexene autoxidation. To sample the cluster structures, we employ our recently developed systematic hydrate sampling technique and identify a total of 551 hydrate clusters...
November 1, 2018: Journal of Physical Chemistry. A
István E Sajó, László P Bakos, Imre M Szilágyi, György Lendvay, József Magyari, Miklós Mohai, Ágnes Szegedi, Attila Farkas, Anna Jánosity, Szilvia Klébert, László Kótai
[NH4 Cu(OH)MoO4 ] as active photocatalyst in the decomposition of Congo Red when irradiated by UV or visible light has been prepared in an unusual ammonia/water ligand exchange reaction of [tetraamminecopper(II)] molybdate, [Cu(NH3 )4 ]MoO4 . [Cu(NH3 )4 ]MoO4 was subjected to moisture of open air at room temperature. Light blue orthorhombic [Cu(NH3 )(H2 O)3 ]MoO4 was formed in 2 days as a result of an unexpected solid/gas phase ammonia-water ligand exchange reaction. This complex does not lose its last ammonia ligand on further standing in open air; however, a slow quasi-intramolecular (self)-protonation reaction takes place in 2-4 weeks, producing a yellowish-green microcrystalline material, which has been identified as a new compound, [NH4 Cu(OH)MoO4 ], ( a = 10,5306 Å, b = 6...
November 5, 2018: Inorganic Chemistry
Gerhard König, Frank C Pickard, Jing Huang, Walter Thiel, Alexander D MacKerell, Bernard R Brooks, Darrin M York
Maintaining a proper balance between specific intermolecular interactions and non-specific solvent interactions is of critical importance in molecular simulations, especially when predicting binding affinities or reaction rates in the condensed phase. The most rigorous metric for characterizing solvent affinity are solvation free energies, which correspond to a transfer from the gas phase into solution. Due to the drastic change of the electrostatic environment during this process, it is also a stringent test of polarization response in the model...
October 19, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Zhaoning Song, Niraj Shrestha, Suneth C Watthage, Geethika K Liyanage, Zahrah S Almutawah, Ramez H Ahangharnejhad, Adam B Phillips, Randy J Ellingson, Michael J Heben
Organic-inorganic metal halide perovskites are notoriously unstable in humid environments. While many studies have revealed the morphology and crystal structure changes that accompany exposure to humidity, little is known about changes to the photophysics that accompany the degradation process. By combining in situ steady-state and time-resolved photoluminescence with Hall effect measurements, we examined the changes in the photoexcited carrier dynamics for methylammonium lead iodide (MAPbI3 ) and bromide (MAPbBr3 ) films exposed to nitrogen gas containing water vapor at 80% relative humidity...
November 1, 2018: Journal of Physical Chemistry Letters
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"