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91.
研究了在零度和非零度时的双原子分子离子HBr+在不同包络函数的超快激光脉冲作用下的光解离动力学. 主要计算了HBr+电子基态时的参数. 利用从头算理论在CCSD/6-311++G(3df,2pd)水平计算了HBr+的势能值,用Morse参数模拟后,与非依时傅立叶格点哈密顿方法获得的束缚态振动能量本征值进行比较. 另外,探索了温度、脉冲包络函数和光强度对光解离过程的影响. 相似文献
92.
VA Tamhane DG Dhaware N Khandelwal AP Giri V Panchagnula 《Journal of colloid and interface science》2012,383(1):177-183
Bicontinuous microemulsions (BCMEs) have excellent solubulizing properties along with low interfacial tension and aqueous content that can be controlled. In this work, water soluble plant protease inhibitor (PI), well characterized for its activity against insect pests, was incorporated into a BCME system and explored for permeation on hydrophobic leaf surfaces and protease inhibition activity. The bicontinuous nature of the microemulsion containing water:2-propanol:1-butanol (55:35:10 w/w) was characterized using conductivity and self-diffusion coefficient measurements. The PI was soluble in the water-rich bicontinuous domains, stable in the microemulsions, and protease inhibition activity was retained for a prolonged duration. The microemulsions ensured greater wettability and a wider spread of the PI on hydrophobic leaf surfaces as revealed by contact angle measurements. Significantly, trypsin inhibition activity assays of the PI recovered from the leaves after delivery from the microemulsion indicated a significant increase in the PI retention on the leaf. This BCME enabled greater leaf permeation and retention of the PI can be attributed to a temporary disruption of the waxy leaf surface followed by self-repair without causing any long term damage to the plant. 相似文献
93.
Chattaraj PK Giri S Duley S 《The journal of physical chemistry. A》2012,116(1):790-1; discussion 792-5
94.
Shulin Zhao Chandan Prasad Hugh J. F. Robertson Y.-M. Liu 《Analytical and bioanalytical chemistry》2001,369(3-4):220-224
A capillary electrophoresis (CE) method with laser induced fluorescence (LIF) detection is described for quantification of enterostatin (Val-Pro-Asp-Pro-Arg), a pentapeptide involved in appetite regulation and insulin secretion. Enterostatin and two other pentapeptides belonging to the enterostatin family (i.e. Ala-Pro-Gly-Pro-Arg and Val-Pro-Gly-Pro-Arg) were well separated from each other. The peptides were fluorescently tagged with naphthalene-2,3- dicarboxaldehyde (NDA) and separated by micellar electrokinetic chromatography (MEKC) in the presence of methanol as an organic modifier. Coupled with LIF detection, the method had a detection limit of 4.8 × 10–6 M for enterostatin. The relative standard deviation was to be 4.0% from five determinations of enterostatin at 37.2 μM in a human cerebrospinal fluid (CSF) sample. Twenty-three human CSF samples were analyzed. The level of enterostatin ranged from 24 μM to 51 μM with a mean (± SEM) value of 41.7 ± 2.0 μM. 相似文献
95.
Ashok K. Varma Ashwini Nangia Gautam R. Desiraju Venkatachalam S. Giri Parasuraman Jaisankar 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(1):97-99
3-Acetyl-1,6,7,12b-tetrahydroindolo[2,3-a]quinolizin-2(12H)-one, C17H16N2O2, consists of two symmetry-independent molecules and each forms a layered structure stabilized by N—H⃛O and C—H⃛O hydrogen bonds. In 3-acetyl-6,7-dihydroindolo[2,3-a]quinolizin-4(12H)-one monohydrate, C17H14N2O2·H2O, the structure is stabilized by O—H⃛O, N—H⃛O and C—H⃛O hydrogen bonds, with the ordered water molecule playing a crucial role in the self-assembly. Contribution from the weak interactions to the strong hydrogen-bonded network is a common feature in both structures. 相似文献
96.
Chapala Vijaya Lakshmi Katari Naresh Kumar Malavattu Giri Prasad Kerru Nagaraju Reddy Pedavenkatagari Narayana Marisetti Vishnu Murthy 《Russian Journal of General Chemistry》2021,91(5):932-938
Russian Journal of General Chemistry - Large-scale enantioselective synthesis of the chiral amine unit of HCV NS5A inhibitor Elbasvir has been accomplished in six steps, with 55% overall yield. The... 相似文献
97.
Narayan C. Giri 《Annals of the Institute of Statistical Mathematics》1988,40(2):381-394
In this paper we give an extension of the theory of local minimax property of Giri and Kiefer (1964, Ann. Math. Statist., 35, 21–35) to the family of elliptically symmetric distributions which contains the multivariate normal distribution as a member.This work was partially supported by the Canadian N.S.E.R.C. grant 相似文献
98.
We study the effect of the FCNC mediated Z boson in the rare semileptonic baryonic decays Λb → Λl+l-. We consider the model where the standard model fermion sector is extended by an extra vector-like down quark, as a consequence
of which it allows for CP-violating Z mediated flavor changing neutral current at the tree level. We find that due to this non-universal Zbs coupling, the branching ratios of the rare semileptonic Λb decays are enhanced reasonably from their corresponding standard model values and the zero point of the forward-backward
asymmetry for Λb → Λμ+μ- is shifted to the left.
Received: 2 June 2005, Published online: 26 October 2005
PACS:
13.30.Ce, 12.60.-i, 11.30.Hv 相似文献
99.
100.
We have studied some of the two body nonleptonic decays ofB meson in the context of heavy quark effective theory using factorization hypothesis. Treatinga
1 as a free parameter, we have obtained its value asa
1=0.822±0.045, by correlating the experimental and predicted branching ratio for
process. With this value ofa
1 the branching ratios obtained for other decay channels are in good agreement with the experiment. The decay constant ofD meson is extracted to be 280.82 MeV. Heavy quark spin symmetry has also been tested. 相似文献