192,195 research outputs found
Mesophilic-hydrothermal-thermophilic (M-H-T) digestion of green corn straw
No full textMesophilic-hydrothermal (80-160 degrees C, 30 min)-thermophilic (M-H-T) digestion and control tests of mesophilic (M), thermophilic (T), hydrothermal-mesophilic (H-M), and mesophilic-thermophilic digestion (M-T) of green corn straw were conducted for a 20-day fermentation period. The results indicate that M-H-T is an efficient method to improve methane production. A maximum methane yield of 371.74 mL/g volatile solid was obtained by the M (3 days)-H (140 degrees C)-T (17 days) process, which was 20.44%, 16.55%, 31.44%, and 14.31% higher than the yields of the M, T, 140-M, and M-T processes. The enhanced methane production was attributed to (1) the improved hemicellulose degradation and lignin disorganization; (2) prevention of the degradation of soluble sugar, easily hydrolyzed hemicellulose and cellulose into furfural and methylfurfural; and (3) lack of formation of Maillard reaction products during initial hydrothermal treatment. (C) 2015 Elsevier Ltd. All rights reserved
Gas-phase chemistry of nitrogen trifluoride NF3: structure and stability of its M+-NF3 (M = H, Li, Na, K) complexes
No full textThe stationary points characterizing the potential energy profiles of the complex processes of the M+(M = H, Li, Na, K) and NF3 were investigated by QCISD and B3LYP in conjunction with the 6-311 + G(2d,2p) basis set. The optimized geometries and NBO analysis indicate that the complexes of M+(M = Li, Na, K) and NF3 exist as ion-dipole molecules. But for H+ complexes, there are two stable isomers NF3H+ and NF2+-HF. The interaction distances of isomers follow the sequence H+ < Li+ < Na+ < K+. The calculated affinity energies of the most stable isomers of H+, Li+, Na+, and K+ complexes exceed 20.1 kJ/mol, and these values suggest that the M+-NF3 (M = H, Li, Na, K) complexes could be observed as stable species in gas phase, which supports Fujii's proposal that Li+ ion attachment mass spectrometry can serve as a conceivable technique to quantify the emissions of the NF3. (C) 2003 Elsevier B.V. All fights reserved
Interfacial “Single-Atom-in-Defects” Catalysts Accelerating Li+ Desolvation Kinetics for Long-Lifespan Lithium-Metal Batteries
No full textThe lithium-metal anode is a promising candidate for realizing high-energy-density batteries owing to its high capacity and low potential. However, several rate-limiting kinetic obstacles, such as the desolvation of Li+ solvation structure to liberate Li+, Li0 nucleation, and atom diffusion, cause heterogeneous spatial Li-ion distribution and fractal plating morphology with dendrite formation, leading to low Coulombic efficiency and depressive electrochemical stability. Herein, differing from pore sieving effect or electrolyte engineering, atomic iron anchors to cation vacancy-rich Co1−xS embedded in 3D porous carbon (SAFe/CVRCS@3DPC) is proposed and demonstrated as catalytic kinetic promoters. Numerous free Li ions are electrocatalytically dissociated from the Li+ solvation complex structure for uniform lateral diffusion by reducing desolvation and diffusion barriers via SAFe/CVRCS@3DPC, realizing smooth dendrite-free Li morphologies, as comprehensively understood by combined in situ/ex situ characterizations. Encouraged by SAFe/CVRCS@3DPC catalytic promotor, the modified Li-metal anodes achieve smooth plating with a long lifespan (1600 h) and high Coulombic efficiency without any dendrite formation. Paired with the LiFePO4 cathode, the full cell (10.7 mg cm−2) stabilizes a capacity retention of 90.3% after 300 cycles at 0.5 C, signifying the feasibility of using interfacial catalysts for modulating Li behaviors toward practical applications
Thermodynamic Modeling of the Li-H and Ca-H Systems
No full textThe phase diagram and thermodynamic properties of the Li-H and Ca-H systems in the literature are critically reviewed. The Gibbs energy functions of individual phases in these two systems are modeled by the CALPHAD approach. The associate solution model and substitutional model are employed to represent the thermodynamic properties of the liquid phase in the Li-H and Ca-H systems, respectively. The available experimental data are well reproduced by the present modeling. With the obtained Gibbs energy functions, the phase relationships in the Li-H and Ca-H systems at high pressures are also predicted
M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data: v1.2.0
No full text<p>Q4/23-Release of the whole project repository, including the schema and data folders.</p>
<h2>What's Changed</h2>
<ul>
<li>Increment schema minor version by @theodore-s-beers in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/369</li>
<li>Update readme by @theodore-s-beers in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/370</li>
<li>Update links by @theodore-s-beers in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/372</li>
<li>Auto-format files by @theodore-s-beers in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/374</li>
<li>Use CRediT roles in schema by @theodore-s-beers in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/375</li>
<li>Add meeting protocol by @theodore-s-beers in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/376</li>
<li>Housekeeping by @theodore-s-beers in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/382</li>
<li>update changelog by @XeniaMonika in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/384</li>
<li>Edit schema changelog by @theodore-s-beers in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/385</li>
<li>Add CRediT role IDs by @theodore-s-beers in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/388</li>
<li>add missing keywords by @XeniaMonika in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/390</li>
<li>add project by @XeniaMonika in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/391</li>
<li>add new projects by @XeniaMonika in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/393</li>
<li>add date by @XeniaMonika in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/394</li>
<li>Add new projects by @XeniaMonika in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/395</li>
<li>Fix relation: kalimat and oes by @XeniaMonika in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/396</li>
<li>add projects by @XeniaMonika in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/397</li>
<li>Auto-format files by @theodore-s-beers in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/398</li>
<li>add projects by @XeniaMonika in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/400</li>
<li>add projects by @XeniaMonika in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/401</li>
<li>fix minor mistakes in keywords by @XeniaMonika in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/402</li>
<li>add projects by @XeniaMonika in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/403</li>
<li>Merge upstream changes by @theodore-s-beers in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/405</li>
<li>Housekeeping by @theodore-s-beers in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/404</li>
<li>add projects by @XeniaMonika in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/406</li>
<li>Auto-format files by @theodore-s-beers in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/407</li>
<li>Fix broken links by @theodore-s-beers in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/408</li>
<li>Update keywords by @XeniaMonika in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/410</li>
<li>Auto-format files by @theodore-s-beers in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/411</li>
<li>Housekeeping by @theodore-s-beers in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/412</li>
<li>Edit meeting protocol by @theodore-s-beers in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/415</li>
<li>update the protocole and add a link by @XeniaMonika in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/414</li>
<li>Update Prettier dependency by @theodore-s-beers in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/416</li>
<li>Update branch name by @theodore-s-beers in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/417</li>
<li>add project: elephantine by @XeniaMonika in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/418</li>
<li>Add <code>maintained</code> field to schema by @theodore-s-beers in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/419</li>
<li>Mark projects as maintained by @theodore-s-beers in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/421</li>
<li>Edit project description by @theodore-s-beers in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/422</li>
<li>bump the schema to 0.2.2 by @XeniaMonika in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/423</li>
<li>fix to project end date by @mabarber92 in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/425</li>
<li>add project: classicmayan by @XeniaMonika in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/426</li>
</ul>
<h2>New Contributors</h2>
<ul>
<li>@mabarber92 made their first contribution in https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/pull/425</li>
</ul>
<p><strong>Full Changelog</strong>: https://github.com/M-L-D-H/Closing-The-Gap-In-Non-Latin-Script-Data/compare/v1.1.0...v1.2.0</p>
INFRARED SPECTROSCOPY OF M(CH)(HO) CLUSTERS (M=Li, Na): INDUCING HOHO AND HOCH HYDROGEN BONDS IN METHANATED CLUSTERS
No full textAuthor Institution: Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801Experiments on M(CH)(HO) (M=Li and Na) have been carried out using tandem mass spectrometry and infrared spectroscopy in the O-H stretching region from 3400 cm to 3800 cm. We have found, for example, that a single CH can induce hydrogen bonded conformers in the cases of Li(CH)(HO)Ar, which are absent in the Li(HO)Ar spectra {\textbf{130}}, 15381 (2008).} {\textbf{130}}, 15393 (2008).}. Furthermore, upon addition of multiple CH ligands, hydrogen bonding is not only maintained, but features associated with HOCH hydrogen bonds are more intense, indicating the affinity of CH to bind to available O-H sites. Spectra of Li(CH)(HO) and Na(CH)(HO) clusters will also be discussed, all of which exhibit the curious trait of HOHO and HOCH hydrogen bonding in the presence of hydrophobic, non-polar CH. To better understand the nature and onset of HOCH hydrogen bonding, the Li(CH)(HO) spectra will be discussed
ESTUDIO DEL EFECTO DE ISOTÓPO DE HIDRÓGENO EN LOS COMPLEJOS M–H•••H–F (M=Li, Na)
No full textSe estudió teóricamente el efecto de isotópo de hidrógeno sobre la geometría, la distribución de carga electrónica, la estabilidad relativa y la energía de formación de complejos lineales tipo M–X···Y–F y todos sus isotopólogos de hidrógeno (M=Li, Na; X, Y= H, D, T). Estos estudios fueron realizados con el paquete computacional APMO a un nivel de teoría Hartree-Fock electrónico y nuclear. Los resultados obtenidos están de acuerdo con resultados reportados por otros autores que usan métodos de estructura electrónica convencional. </p
L'organizzazione strutturale di liquidi dipolari in soluzioni elettrolitiche rivelata dall'effetto di noncoincidenza Raman: il caso ddelle soluzioni d Li+/Carbonato di Propilene (PC) e Li+/(PC+DMC)
No full textNegli ultimi anni sono state raccolte svariate evidenze che indicano che l’effetto di noncoincidenza (NCE), ovvero la separazione spettrale fra il profilo anisotropo ed isotropo di una banda Raman totalsimmetrica, costituisca un osservabile spettroscopico intimamente correlato con la struttura microscopica di un liquido molecolare. Nell’ambito di una estesa attività spettroscopica rivolta a stabilire questa correlazione, abbiamo recentemente indagato le alterazioni che NCE della banda (C=O) di solventi carbonilici subisce come conseguenza della presenza di ioni alcalini ed alcalino terrosi in soluzioni elettrolitiche [1,2]. L’uso congiunto di calcoli quanto chimici ci ha permesso di stabilire in modo inequivocabile una correlazione fra il valore negativo di NCE osservato per questa banda in una soluzione Li+/acetone e la struttura delle specie clusterizzate Mm+(acetone)n presenti nelle soluzioni elettrolitiche e di giustificare il progressivo aumento del valore negativo di NCE della banda (C=O) con l’aumento della densità di carica dello ione Mm+.
Per la rilevanza rivestita dal Carbonato di Propylene (PC) come solvente nello sviluppo di batterie secondarie per la sua elevata permettività elettrica (=64) abbiamo esteso lo studio di NCE a soluzioni elettrolitiche Li+/PC. Il valore di NCE che per la banda (C=O) di PC puro risulta piccolo e positivo (NCE=5 cm-1), e cambia in modo molto evidente in soluzione Li+/PC (xLi+=0.09), diventando negativo e molto grande (NCEexper. =-41 cm-1 ), come atteso, per la formazione di clusters Li+(PC)n. I calcoli quanto chimici dello spettro Raman anisotropo ed isotropo della banda (C=O) condotto per svariati clusters Li+/(PC)n (n=2, 3, e 4) indicano che l’osservazione di un valore negativo così elevato di NCE è compatibile solo con la formazione della specie con n=4 (NCEcalc(n=2)=....., NCEcalc (n=3), NCEcalc (n=4) = -35 cm-1) in cui i quattro gruppi C=O puntano tetraedricamente verso lo ione Li+ (gruppo di punti Td).
Abbiamo esteso questo tipo di indagine ad altri solventi carbolinilici come dietil (DEC) ed etil-metil (EC) carbonato che sono usati spesso come co-solventi nelle batterie al litio per ridurre la viscosità della soluzione elettrolitica Li/PC. Risultati preliminari condotti su una soluzione equimolare di PC/DEC sembrano indicare una solvatazione preferenziale di Li+ da parte del PC.
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Bibliografia
[1] M. G. Giorgini, H. Torii, M. Musso, G. P. Venditti, J. Phys. Chem. B 112, 7506 (2008).
[2] M. G. Giorgini, H. Torii, M. Musso, Phys. Chem. Chem. Phys. 12, 183 (2010)
Platinum-group elements and geochemical characteristics of the Permian continental flood basalts in the Tarim Basin, northwest China: Implications for the evolution of the Tarim Large Igneous Province
No full textAbstract not availableYin-Qi Li, Zi-Long Li, Ya-Li Sun, M. Santosh, Charles H. Langmuir, Han-Lin Chen, Shu-Feng Yang, Zhong-Xing Chen, Xing Y
Cambio iónico H+/M+EN a-TP (M=Li, K, Cs). Estudio termodinámico y microcalorimétrico
No full textSe estudian las propiedades de cambio iánico del L_TP en sistemas H+/M+ ((M=LI K CS). Las experiencias se efectúan a temperaturas de 25 40 y 55 OC. Se obtienen isotermas de cambio y curvas de valoración e hidrólisis. Se determinan los valores de las magnitudes termodinámicas de cambio en los sistemas H+/LI+ Y H+/K+ utilizando el método de Gaines y Thomas. Se efectúan medidas calorimétricas directas que confirman los resultados obtenidos mediante el uso de métodos clásicos
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