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1.
The study is concerned with the Stefan problem of evaporation of a volatile component from its solution with a virtually non-volatile
material. The analysis provides an analytical solution to the problem based on mass-transfer fundamentals. Results yield the
evaporation rate, interfacial mole fractions, concentration profiles in the gas and liquid phases, and the location of the
evaporation front. The analysis can be used to provide the binary liquid diffusion coefficient of the volatile component based
on experimental data for the liquid–gas interface position as a function of time. The requirements for such a measurement
are discussed in terms of the volatility of the evaporating component and its initial concentration in the liquid mixture.
Fig. 1 Gas–liquid interface movement in a partially filled tube
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2.
3.
M. Hammouda Z. M. Abou Zeid H. A. Etman M. A. Metwally 《Chemistry of Heterocyclic Compounds》2011,47(1):17-21
Alkyl 4-oxo-2-phenylamino-4,5-dihydrofuran-3-carboxylates were used for the preparation of alkyl 5-amino-7-aryl-2-{[aryl(hydroxy)methyl](phenyl)amino}-4,6-dicyano-1-benzofuran-3-carboxylates,
4-oxo-2-phenylamino-N-(p-tolyl)-4,5-dihydrofuran-3-carboxamide, and ethyl 4-chloro-5-formyl-2-(phenylamino)furan-3-carboxylate.
The latter was used for the synthesis of ethyl 4-chloro-5-(hydrazinylidenemethyl)-2-(phenylamino)furan-3-carboxylate and diethyl
5,5'-(hydrazine-1,2-di-ylidenemethylylidene)bis[4-chloro-2-(phenylamino)furan-3-carboxylate]. 相似文献
4.
开发了标题化合物(C7H11N2)2[CdCl4]·0.5H2O (C7H11N2=4-(二甲基氨基)吡啶鎓)的制备程序,并得到良好的收率和纯度。Cd(Ⅱ)离子在略微扭曲的四面体环境中与4个氯离子配位。晶体排列显示出层状结构,有机层和无机层交替排列,平行于(001)平面,位于x=n+1/2(n∈Z)。在晶体中,有机层和无机层通过C—H…Cl、C—H…O、N—H…Cl和N—H…O氢键相互作用连接。Hirshfeld表面分析和结构的指纹图表明分子堆积受氢键和π堆积的控制。UV-Vis漫反射光谱使我们能够用Tauc外推法确定具有半导体特性的3.596 eV的直接带隙。观察到的在562 nm处具有最大值的光致发光带归属于4-(二甲基氨基)吡啶鎓阳离子中的激发π-π*态。 相似文献
5.
Small‐Angle Neutron Scattering has been performed from poly(ethylene oxide) in deuterated water at temperature ranging from 10 to 80 °C. A simple fitting model was used to obtain a correlation length and a Porod exponent. The correlation length L characterizes the average distance between entanglements in the semidilute region and is proportional to the individual coil sizes in the dilute region. L was found to increase with temperature in the semidilute region but it decreases with temperature in the dilute region. This decrease is the precursor to the single‐chain collapse which applies to very dilute polymer solutions. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2196–2200, 2007 相似文献
6.
We use Zimm's single-contact approximation to investigate the concentration dependence of the first cumulant for partially labeled chains in dilute solutions. This approximation allows us to express interchain properties (such as the interference part of the generalized mobility) in terms of static structure factors, which are then modeled using a Gaussian chain model. We present numerical results for three specific labeling sequences. 相似文献
7.
Simple and accurate prediction methods of the thermodynamic and the transport properties of Freon-22 as a function of pressure and temperature are presented in this paper. The code predicts the thermodynamic and the transport properties for subcooled and saturated liquid and for saturated and superheated vapour. Predictions were compared to various experimental data and showed good agreement.
Auswertung thermophysikalischer Eigenschaften von Frigen R 22
Zusammenfassung Im folgenden Bericht wird ein Rechenprogramm für einfache aber genaue Berechnungen von thermodynamischen und Transporteigenschaften von Frigen R 22 als Funktion von Druck und Temperatur vorgestellt. Das Programm erlaubt ein Voraussagen dieser Eigenschaften sowohl für unterkühlte und gesättigte Flüssigkeiten als auch für gesättigten und überhitzten Dampf. Beim Vergleich verschiedener Versuchsdaten mit den Ergebnissen dieses Codes konnten gute Übereinstimmungen festgestellt werden.相似文献
8.
Rouquette J Haines J Al-Zein A Papet P Damay F Bourgeois J Hammouda T Doré F Maignan A Hervieu M Martin C 《Physical review letters》2010,105(23):237203
The electronic ferroelectric lutetium ferrite (LuFe(2)O(4)) was studied by x-ray diffraction as a function of pressure. Pressure is shown to induce an irreversible rhombohedral to orthorhombic transition leading to a supercell determined by the combination of electron and synchrotron x-ray diffraction. This new configuration is proposed to be charge ordered in agreement with the results of resistivity measurements. 相似文献
9.
Because of a relatively low atomic packing density, (Cg) glasses experience significant densification under high hydrostatic pressure. Poisson's ratio (nu) is correlated to Cg and typically varies from 0.15 for glasses with low Cg such as amorphous silica to 0.38 for close-packed atomic networks such as in bulk metallic glasses. Pressure experiments were conducted up to 25 GPa at 293 K on silica, soda-lime-silica, chalcogenide, and bulk metallic glasses. We show from these high-pressure data that there is a direct correlation between nu and the maximum post-decompression density change. 相似文献
10.
An alkali‐soluble polysaccharide, GM5‐1, from the mycelium of Ganoderma tsugae, was fractionated by the nonsolvent addition method. The weight‐average molecular mass (M w) and intrinsic viscosity ([η]) of fractions were studied by laser light scattering and viscometry with dimethylsulfoxide (DMSO) containing 0.25M LiCl (0.25M LiCl/DMSO) as the solvent at 30°C. The dependences of [η] and the radius of gyration (?S 2?z 1/2) on M w were found to be [η]=9.8×10?2 M w 0.57 (cm3g?1) and ?S 2?z 1/2=1.65×10?2 M w 0.58 (nm) in the M w range from 8.6×105 to 2.6×106. The analysis based on current theories for a wormlike chain showed that the chain conformational parameters of GM5‐1 were 4.2 nm for persistence length (q) and 833 nm?1 for linear mass density (ML) with an obvious excluded volume effect. The results suggested the alkali‐soluble polysaccharide behaves like a semiflexible chain in 0.25M LiCl/DMSO at 30°C. 相似文献