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1.
Mixing rules are derived for mass diffusion coefficient and thermal diffusion factor matrices by developing compatibility conditions between the fluid mixture equations obtained from nonequilibrium thermodynamics and Grad's 13-moment kinetic theory. The mixing rules are shown to be in terms of the species mole fractions and binary processes. In particular, the thermal diffusion factors for binary mixtures obtained by the Chapman-Enskog expansion procedure are suitably generalized for many-component mixtures. Some practical aspects of the results are discussed including the utilization of these mixing rules for high pressure situations.  相似文献   
2.
Journal of Sol-Gel Science and Technology - In the present work, Nickel doped Molybdenum trioxide (NixMoO3) where Ni = X (X = 5, 10, and 15%) nanoparticles (NPs) were...  相似文献   
3.
Metallosurfactant complexes of the type trans- [Co(DH)2(HA)X], where DH = Dimethyl glyoxime, HA = Hexadecyl amine and X = Cl, Br, I, N3 , NO2 or SCN, were synthesized and characterized by physico-chemical and spectroscopic methods. In addition, the single crystal X-ray structure of the ionic complex trans-[Co(DH)2(HA)2][Co(DH)2(I)2)] is presented. The critical micelle concentration values of the complexes in ethanol were obtained by measuring the absorption at 290 nm. Specific conductivity data (at 303–313 K) served for the evaluation of the thermodynamics of micellization ) \left( {\Updelta G^{0}_{{{\text{m}}}}, \Updelta H^{0}_{{{\text{m}}}}, \Updelta S^{0}_{\text{m}} } \right) . Steady-state photolysis, cyclic voltammetry and biological activities of the complexes were studied. The compounds were tested for antimicrobial activity.  相似文献   
4.
A group-contribution model for predicting pure-component vapour pressures, in part based on the UNIFAC method for vapour—liquid equilibria, has been extended to include hydrocarbons of molecular weights below 500 containing nitrogen or sulphur. Good representation is obtained for vapour pressure data in the region 10–2000 mmHg. In addition, the accuracy of the method is tested by prediction of heats of vapourization via the Clausius—Clapeyron equation. The predicted heats of vapourization agree with the experimental values within a few percent. In absence of experimental data, the model may be used to estimate vapour pressures and heats of vapourization for the category of compounds studied.  相似文献   
5.
We present the first simultaneous measurement of the ratio of branching fractions, R=B(t --> Wb)/B(t --> Wq), with q being a d, s, or b quark, and the top-quark pair production cross section sigma(tt[over]) in the lepton plus jets channel using 0.9 fb(-1) of pp[over] collision data at sqrt(s)=1.96 TeV collected with the D0 detector. We extract R and sigma(tt[over]) by analyzing samples of events with 0, 1, and > or =2 identified b jets. We measure R=0.97(+0.09)/(-0.08)(stat+syst) and sigma(tt[over])=8.18(+0.09)(-0.84)(stat+syst) +/- 0.50(lumi) pb, in agreement with the standard model prediction.  相似文献   
6.
We present the first measurement of the integrated forward-backward charge asymmetry in top-quark-top-antiquark pair (tt) production in proton-antiproton (pp) collisions in the lepton+jets final state. Using a b-jet tagging algorithm and kinematic reconstruction assuming tt + X production and decay, a sample of 0.9 fb(-1) of data, collected by the D0 experiment at the Fermilab Tevatron Collider, is used to measure the asymmetry for different jet multiplicities. The result is also used to set upper limits on tt+X production via a Z' resonance.  相似文献   
7.
We report the direct observation of the excited L=1 state B_(s2)(*) in fully reconstructed decays to B+K-. The mass of the B_(s2)(*) meson is measured to be 5839.6+/-1.1(stat)+/-0.7(syst) MeV/c(2), and its production rate relative to the B+ meson is measured to be [1.15+/-0.23(stat)+/-0.13(syst)]%.  相似文献   
8.
Titanium oxide thin films have been deposited by an ion plating technique under rf glow. The structure of the deposited film has been found to be amorphous and the composition has been analysed by IR spectrum. Aging and annealing studies of the titanium oxide capacitors have been made. The dielectric constant of the film at 1 kHz has been estimated to be 12.4. The dependence of the capacitance and dielectric loss on frequency and temperature have been studied, and the results are discussed. The temperature coefficient of the capacitance has also been calculated.  相似文献   
9.
Twelve surfactant Schiff base ligands were synthesized from salicylaldehyde and its chloro-, bromo- and methoxy- derivatives by condensation with long-chain aliphatic primary amines, and a number of mixed ligand cobalt(III) surfactant Schiff base coordination complexes of the type [Co(trien)A]2+ were synthesized from the corresponding dihalogeno complexes by ligand substitution. The Schiff bases and their complexes were characterized by physico-chemical and spectroscopic methods. The complexes form foams in aqueous solution upon shaking. The critical micelle concentration (CMC) values of the complexes in aqueous solution were obtained from conductance measurements. Specific conductivity data (at 303–323 K) served for the evaluation of the thermodynamics of micellization ( \Updelta G\textm0 \Updelta G_{\text{m}}^{0} , \Updelta H\textm0 \Updelta H_{\text{m}}^{0} , \Updelta S\textm0 \Updelta S_{\text{m}}^{0} ). The complexes were tested for its antimicrobial activity.  相似文献   
10.
In this work, we have rationally designed and synthesized two new reagents ( L1 and L2 ), each bearing a pendant aldehyde functionality. This aldehyde group can take part in cyclization reactions with β‐ or γ‐amino thiols to yield the corresponding thiazolidine and thiazinane derivatives, respectively. The intramolecular charge‐transfer (ICT) bands of these thiazolidine and thiazinane derivatives are distinctly different from those of the molecular probes ( L1 and L2 ). Such changes could serve as a potential platform for using L1 and L2 as new colorimetric/fluorogenic as well as ratiometric sensors for cysteine (Cys) and homocysteine (Hcy) under physiological conditions. Both reagents proved to be specific towards Cys and Hcy even in the presence of various amino acids, glucose, and DNA. Importantly, these two chemodosimetric reagents could be used for the quantitative detection of Cys present in blood plasma by using a pre‐column HPLC technique. Such examples are not common in contemporary literature. MTT assay studies have revealed that these probes have low cytotoxicity. Confocal laser scanning micrographs of cells demonstrated that these probes could penetrate cell membranes and could be used to detect intracellular Cys/Hcy present within living cells. Thus, the results presented in this article not only demonstrate the efficiency and specificity of two ratiometric chemodosimeter molecules for the quantitative detection of Cys and Hcy, but also provide a strategy for developing reagents for analysis of these vital amino acids in biological samples.  相似文献   
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