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981.
We construct a Schroedinger field theory invariant under local spatial scaling. It is shown to provide an effective theory of superfluid turbulence by deriving, analytically, the observed Kolmogorov 5/3 law and to lead to a Biot–Savart interaction between the observed filament excitations of the system as well.  相似文献   
982.
This work aims to study the trans and cis conformers of furfural, thiofurfural and selenofurfural in the gas and solution phases. Assuming that there is equilibrium between these conformers, the transition state has also been investigated. All computations have been done using density functional theory method with B3LYP as the functional and 6-311++G(d,p) as the basis sets. The optimized molecular structures and related parameters of these conformers are reported. The infrared wavenumbers and Raman activities of these conformers are also reported with appropriate assignments. The energy differences between the trans and cis conformers, associated barriers and thermodynamical parameters have been derived from the computations. It is found that the structural parameters are not much different in the gas and solution phases. However, in the gas phase, the trans conformer is always more stable, but increasing the polarity of the solvent leads to the cis conformer becoming more stable. The rotational barrier is always larger than the energy difference and both of them increase when the solvent becomes more polar. Some of the results for furfural compare satisfactorily with literature and therefore the data from this work will be useful for thiofurfuraldehyde and selenofurfuraldehyde, as their literature is limited.  相似文献   
983.
Losartan is an effective anti‐hypotension drug frequently used in clinic. Compound danshen tablet (CDST) is an important traditional Chinese multiherbal formula composed of Danshen, Sanqi and Bingpian, which is widely used for the treatment of cardiovascular and cerebrovascular diseases in China. More often, losartan and CDST are simultaneously used for the treatment of anti‐hypertension in the clinic. The aim of this study was to compare the pharmacokinetics of losartan and EXP3174 after oral administration of single losartan and both losartan and CDST, and to investigate the influence of CDST on the pharmacokinetics of losartan and its metabolite EXP3174. Male Sprague–Dawley rats were randomly assigned to two groups: a losartan‐only group and a losartan and CDST group. Plasma concentrations of losartan and EXP3174 were determined by LC‐MS at designated points after drug administration, and the main pharmacokinetic parameters were estimated. It was found that there were significant differences (p < 0.05) between the pharmacokinetic parameters of losartan and EXP3174, which showed that CDST influenced the metabolism and excretion of losartan in vivo. The result could be used for clinical medication guidance of losartan and CDST to avoid the occurrence of adverse reactions. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
984.
The effect of nonionic micelles of Triton X‐100 on the oxidative decarboxylation of l ‐glutamic acid by chloroaurate(III) complexes has been investigated in acetate buffer medium. The reaction is first order with respect to Au(III), but a complex order with respect to glutamate. H+ ion has both accelerating and retarding effects in the pH range 3.72–4.80, whereas a Cl? ion has an inhibiting effect in the range 0.02–0.56 mol dm?3. Under the experimental conditions, AuCl?4 and AuCl3(OH)? are the predominant and effective oxidizing species, whereas the zwitterion (H2A) and mononegative anion (HA?) are the predominant reducing species of the amino acid. The reaction involves a one‐step two‐electron transfer process and passes through the intermediate formation of iminic cation. In the presence of surfactant, the reaction passes through a maximum and it appears to follow Berezin's model, where both the oxidant and the substrate are partitioned between the aqueous and the micellar phase and then react. The binding constants between the reactants and the surfactant have been evaluated at different temperatures. Compensation between substrate–water interaction and substrate–micelle interaction plays an important role in such redox reactions in the presence of a surfactant. © 2012 Wiley Periodicals, Inc. Int J Chem Kinet 44: 482–493, 2012  相似文献   
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986.
We predicted elpasolites having the composition A2BCHal6 (A and C stand for different monovalent metals; B stands for trivalent metals; and Hal for F, Cl, or Br) that have not been obtained yet. Prediction was based on the data on properties of elements and simple halides only. The computations were carried out using specialized software for computer-assisted data analysis relying on the precedent-based pattern recognition method.  相似文献   
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