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排序方式: 共有58条查询结果,搜索用时 218 毫秒
41.
This paper describes the results of a study aimed at improving the efficiency of anaerobic digestion of salty cheese whey
in combination with poultry waste or cattle dung. Best results were obtained when salty cheese whey was mixed with poultry
waste in the ratio of 7:3, or cattle dung in the ratio of 1:1, both on dry weight basis giving maximum gas production of 1.2
L/L of digester/d with enriched methane content of 64% and 1.3 L/L of digester/d having methane content of 63% respectively.
Various conditions such as temperature and retention time have been optimized for maximum process performance. 相似文献
42.
Jianhua?RenEmail author Chirag?G.?Patel 《Journal of the American Society for Mass Spectrometry》2005,16(4):535-541
We determined the gas-phase acidity of methylthioacetic acid (MTA) in a triple-quadrupole mass spectrometer using the Cooks’
kinetic method with the consideration of entropy effects. The negatively charged proton-bound dimers were generated by electrospray
ionization. Collision-induced dissociation was applied to the dimer ions and the product ion ratios were measured at four
different collision energies. The gas-phase acidity (ΔH
acid) of MTA was determined to be 340.0±1.7 kcal/mol using the extended kinetic method and 339.8±1.7 kcal/mol using the standard
kinetic method. The entropy term is insignificant in this case and can be ignored. The standard kinetic method yielded a free
energy of deprotonation of MTA (ΔG
acid) of 333.0±1.7 kcal/mol. The entropy of the acid dissociation, ΔS
acid, was estimated to be 22.8 cal/mol K. Theoretical prediction at the B3LYP/6-31+G* level of theory gives a similar value for
ΔH
acid of 338. 9 kcal/mol. In the gas-phase, MTA is a stronger acid than methoxyacetic acid, although in solution, MTA is a weaker
one. 相似文献
43.
The synthesis of aromatic dicarboxaldehydes is described along with their reactivity in the [3 + 3] cyclocondensation reaction with (1R,2R)-diaminocyclohexane to give trianglimine macrocycles. In particular, the scope and limitation of the reaction with regard to complete control of the cavity size of the macrocycles is discussed producing a total of 11 macrocycles with different cavity sizes ranging from 9 to 23 angstroms. 相似文献
44.
Ravibhai Bhola Haresh Modi Chirag Patel Hasit Vaghani Keyur Bhatt Rizwan Ghumara 《印度化学会志》2022,99(5):100427
Solubility of 2, 6-bis (4-hydroxybenzylidene) cyclohexanone (BHBC) in pure solvents such as 1,4-dioxane, methanol, 1-butanol, 1-propanol, ethyl acetate, acetone, tetrahydrofuran (THF), glacial acetic acid, dimethyl sulphoxide (DMSO) and binary solvents dimethyl formamide (DMF) and (1-Propanol + Tetrahydrofuran) were investigated by gravimetric method at different temperature range. The experiment solubility increases with increase in temperature in both pure and binary solvents. The Maximum solubility is found in DMF at 328.15 K and for binary solvent mixture i.e. 1-propanol and THF (0.9 mol fraction) it was maximum at 318.15 K. Further modified Apelblate and Buchowski-Ksiazczak models were used for the theoretical calculation of solubility of BHBC in pure as well binary solvents. A satisfactory correlation of these models with experimental data was observed. The solution thermodynamics parameters like enthalpies, Gibb's free energy of dissolution and entropy of solutions were calculated using Van't Hoff and Gibb's equation, which reveals the solvation mechanism is non-spontaneous and entropy driven. 相似文献
45.
Jojo P. Joseph Chirag Miglani Antarlina Maulik Shema R. Abraham Avisek Dutta Alexander Baev Prof. Paras N. Prasad Prof. Asish Pal 《Angewandte Chemie (International ed. in English)》2023,62(37):e202306751
Designing polymeric systems with ultra-high optical activity is instrumental in the pursuit of smart artificial chiroptical materials, including the fundamental understanding of structure/property relations. Herein, we report a diacetylene ( DA ) moiety flanked by chiral D - and L -FF dipeptide methyl esters that exhibits efficient topochemical photopolymerization in the solid phase to furnish polydiacetylene ( PDA ) with desired control over the chiroptical properties. The doping of the achiral gold nanoparticles provides plasmonic interaction with the PDA s to render asymmetric shape to the circular dichroism bands. With the judicious design of the chiral amino acid ligand appended to the AuNPs, we demonstrate the first example of selective chiral amplification mediated by stereo-structural matching of the polymer-plasmonic AuNP hybrid pairs. Such ordered self-assembly aided by topochemical polymerization in peptide-tethered PDA provides a smart strategy to produce soft responsive materials for applications in chiral photonics. 相似文献
46.
We study a class of deep neural networks with architectures that form a directed acyclic graph(DAG).For backpropagation defined by gradient descent with adaptive momentum,we show weights converge for a large class of nonlinear activation functions.'The proof generalizes the results of Wu et al.(2008)who showed convergence for a feed-forward network with one hidden layer.For an example of the effectiveness of DAG architectures,we describe an example of compression through an AutoEncoder,and compare against sequential feed-forward networks under several metrics. 相似文献
47.
Keyur D. Bhatt Hemangini D. Shah Krunal M. Modi Moksha B. Narechania Chirag Patel 《Supramolecular chemistry》2019,31(4):268-282
A novel supramolecular sensor derived from calix[4]pyrrole system i.e. calix[4]pyrrole bearing aminoanthraquinone derivative (CAAQ) have been designed and synthesized. The complexation behavior of metal cations [Ag(I), Ba(II), Ca(II), Ni(II), Co(II), Fe(III), Hg(II), Cu(II), Cr(II), Pb(II), Zn(II), (1 × 10?4 M)] with CAAQ (1 × 10?6 M) was studied by spectrophotometry and spectrofluorometry. Metal ion like Pb(II) produces red shift in absorption spectra and quenching in emission spectra likelihood of strong complexation of Pb(II) ions with CAAQ. Fluorescence cell imaging also supports the complexation of Pb(II) ions with CAAQ. The binding constants, quantum yield, stoichiometry of complex, mechanism of quenching by Stern–Volmer equation and Density functional theory calculation have been determined. 相似文献
48.
Harsh Kumar Kanchan Bhardwaj Natlia Cruz-Martins Ruchi Sharma Shahida Anusha Siddiqui Daljeet Singh Dhanjal Reena Singh Chirag Chopra Adriana Dantas Rachna Verma Noura S. Dosoky Dinesh Kumar 《Molecules (Basel, Switzerland)》2022,27(11)
Cholesterol is essential for normal human health, but elevations in its serum levels have led to the development of various complications, including hypercholesterolemia (HC). Cholesterol accumulation in blood circulation formsplaques on artery walls and worsens the individuals’ health. To overcome this complication, different pharmacological and non-pharmacological approaches are employed to reduce elevated blood cholesterol levels. Atorvastatin and rosuvastatin are the most commonly used drugs, but their prolonged use leads to several acute side effects. In recent decades, the potential benefit of ingesting yogurt on lipid profile has attracted the interest of researchers and medical professionals worldwide. This review aims to give an overview of the current knowledge about HC and the different therapeutic approaches. It also discusses the health benefits of yogurt consumption and highlights the overlooked phyto-enrichment option to enhance the yogurt’s quality. Finally, clinical studies using different phyto-enriched yogurts for HC management are also reviewed. Yogurt has a rich nutritional value, but its processing degrades the content of minerals, vitamins, and other vital constituents with beneficial health effects. The option of enriching yogurt with phytoconstituents has drawn a lot of attention. Different pre-clinical and clinical studies have provided new insights on their benefits on gut microbiota and human health. Thus, the yogurtphyto-enrichment with stanol and β-glucan have opened new paths in functional food industries and found healthy andeffective alternatives for HC all along with conventional treatment approaches. 相似文献
49.
Design and synthesis of two armed molecular receptor for recognition of Gd3+ metal ion and its computational study 下载免费PDF全文
Brij Mohan Krunal Modi Chirag Patel Pankaj Bhatia Ashwani Kumar Harish Kumar Sharma 《应用有机金属化学》2018,32(10)
New receptor P henylene‐ B is‐ M ethylfuran‐yl‐2‐ M ethyele A cetohydrazide ( PBMMA ) has been synthesized by condensation of hydrazide and 5‐methyl furfural. Synthesized receptor has been fully characterized by IR, 1H NMR, 13C NMR, mass spectroscopic and thermo gravimetric analysis. The receptor PBMMA shows selective recognition potential towards Gd3+ ion when tested with several metal ions such as Na+, K+, Mg2+, Cu2+, Cd2+, Hg2+, Y3+, La3+, Eu3+, Sm3+, Gd3+, Re6+ and Th4+ ion as their sulfates by UV–visible and fluorescence spectroscopic studies. Binding nature of PBMMA with Gd3+ ion was further studied by mass spectroscopic and cyclic voltammetric studies. The stoichiometry of PBMMA‐ Gd3+ ion has been established, 1:1 by Benesi‐Hildebrand plot method and method of continuous variation (Job's plot) with association affinity K = 6.491 × 104 M?1. In addition to these, molecular docking, molecular dynamic stimulation and binding energy of complex; through Density Function theory ?595.66 kcal/mol has also indication of strong binding. The electron transfer energy of Higher occupied molecular orbital (HOMO) to Lower unoccupied molecular orbital (LUMO) is about 4.186 eV and 295 nm for PBMMA‐Gd3+ Complex. 相似文献
50.