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41.
Singh S Chaturvedi J Bhattacharya S 《Dalton transactions (Cambridge, England : 2003)》2012,41(2):424-431
Thiophene-2-thiocarboxylate complexes of Cu(I), [(Ph(3)P)(2)Cu(SCOth)] (1) and H[(Ph(3)P)(2)Cu(SCOth)(2)] (2) (where th = thiophene) were synthesized and characterized structurally by X-ray crystallography. Electronic absorption and emission spectral properties of the two compounds have been studied. Cu(II) complexes, [(TMEDA)Cu(SCOth)(2)] (3b) and [(Phen)Cu(SCOth)(2)] (4a) (where TMEDA = tetramethylethylenediamine; Phen = 1,10-phenanthroline) were prepared and characterized by spectroscopic measurements. 3b and 4a underwent desulfurization under ambient conditions readily yielding the corresponding carboxylate complexes [(TMEDA)Cu(O(2)Cth)(2)] (3a) and [(Phen)Cu(O(2)Cth)(2)·H(2)O] (4b). 3a and 4b have been characterized crystallographically. 相似文献
42.
A. Dhal R. K. Sinha D. Negi T. Trivedi M. K. Raju D. Choudhury G. Mohanto S. Kumar J. Gehlot R. Kumar S. Nath S. S. Ghugre R. P. Singh J. J. Das S. Muralithar N. Madhavan J. B. Gupta A. K. Sinha A. K. Jain I. M. Govil R. K. Bhowmik S. C. Pancholi L. Chaturvedi 《The European Physical Journal A - Hadrons and Nuclei》2012,48(3):1-10
The odd mass nucleus 137Pm has been studied to high spins through the 109Ag(32S, 2p2n)137Pm reaction at an incident beam energy of 150 MeV. The de-exciting ??-rays were detected using an array of 18 Compton suppressed clover detectors. The level scheme of 137Pm has been extended up to $J^\pi = \tfrac{{43}} {2}^ -$ and excitation energy of E x ? 6 MeV with the observation of 42 new gamma transitions. The linear polarization (IPDCO) measurements for the ??-ray transitions have been done for the first time. The spin and parity assignments for most of the reported levels have been made using these results and the coincidence angular anisotropy (RDCO) measurements. The nuclear shape evolution is discussed in the light of Total Routhian Surface (TRS) and Cranked Shell Model (CSM) calculations. 相似文献
43.
This paper considers a general family of Stein rule estimators for the coefficient vector of a linear regression model with nonspherical disturbances, and derives estimators for the Mean Squared Error (MSE) matrix, and risk under quadratic loss for this family of estimators. The confidence ellipsoids for the coefficient vector based on this family of estimators are proposed, and the performance of the confidence ellipsoids under the criterion of coverage probability and expected volumes is investigated. The results of a numerical simulation are presented to illustrate the theoretical findings, which could be applicable in the area of economic growth modeling. 相似文献
44.
The paper describes a new method for the calculation of the Sommerfeld screening parameter σ1. It requires neither the knowledge of the energy separations of spin doublet levels nor is it based on the application of
the Hertz law. The only data required for the calculation are the experimental energy values of the level concerned for the
series of elements belonging to the same subshell in which the element in the question is situated. As an illustration the
values of σ1 are calculated for the L
1, L
2 and L
3 levels for elements belonging to the 4f subshell and these are found to be in excellent agreement with those published earlier by Gokhale and Misra. The method brings
out the constancy of σ1 (L
2
L
3)−σ1(L
1) in a natural way and may thus be regarded as providing theoretical explanation of the Hertz law. 相似文献
45.
Physics of Atomic Nuclei - Neutrino oscillation is an experimentally established phenomenon by which neutrinos undergo flavor transformations periodically as they propagate large enough distances.... 相似文献
46.
A. Dhal R. K. Sinha P. Agarwal S. Kumar Monika B. B. Singh R. Kumar P. Bringel A. Neusser R. Kumar K. S. Golda R. P. Singh S. Muralithar N. Madhavan J. J. Das A. Shukla P. K. Raina K. S. Thind A. K. Sinha I. M. Govil P. K. Joshi R. K. Bhowmik A. K. Jain S. C. Pancholi L. Chaturvedi 《The European Physical Journal A - Hadrons and Nuclei》2006,27(1):33-36
High-spin states in 78Kr have been studied via the 63Cu (19F, 2p2n)78Kr reaction at a beam energy of 60 MeV using the Indian National Gamma Array (INGA). In this nucleus, lifetimes have been
measured upto the Iπ=22+ level in the yrast positive-parity band and upto the Iπ=15- level in the negative-parity band using the Doppler Shift Attenuation Method (DSAM). The deduced transition quadrupole moments
Qt's are found to decrease with rotational frequency for both the bands. 相似文献
47.
Ajit Chaturvedi N. D. Shukla Pramod S. Shukla 《Annals of the Institute of Statistical Mathematics》1992,44(1):157-167
The sequential procedure developed by Bhargava and Srivastava (1973, J. Roy. Statist. Soc. Ser. B, 35, 147–152) to construct fixed-width confidence intervals for contrasts in the means is further analyzed. Second-order approximations for the first two moments of the stopping time and the coverage probability associated with the sequential procedure, are obtained. A lower bound for the number of additional observations after stopping is derived, which ensures the mxact probability of coverage. Moreover, two-stage, three-stage and modified sequential procedures are proposed for the same estimation problem. Relative advantages and disadvantages of these sampling schemes are discussed and their properties are studied. 相似文献
48.
From Linear to Angular Isomers: Achieving Tunable Charge Transport in Single‐Crystal Indolocarbazoles Through Delicate Synergetic CH/NH⋅⋅⋅π Interactions
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Dr. Hui Jiang Dr. Peng Hu Dr. Jun Ye Dr. Apoorva Chaturvedi Dr. Keke K. Zhang Yongxin Li Dr. Yi Long Prof. Denis Fichou Prof. Christian Kloc Prof. Wenping Hu 《Angewandte Chemie (International ed. in English)》2018,57(29):8875-8880
Weak intermolecular interaction in organic semiconducting molecular crystals plays an important role in molecular packing and electronic properties. Here, four five‐ring‐fused isomers were rationally designed and synthesized to investigate the isomeric influence of linear and angular shapes in affecting their molecular packing and resultant electronic properties. Single‐crystal field‐effect transistors showed mobility order of 5,7‐ICZ (3.61 cm2 V?1 s?1) >5,11‐ICZ (0.55 cm2 V?1 s?1) >11,12‐ICZ (ca. 10?5 cm2 V?1 s?1) and 5,12‐ICZ (ca. 10?6 cm2 V?1 s?1). Theoretical calculations based on density functional theory (DFT) and polaron transport model revealed that 5,7‐ICZ can reach higher mobilities than the others thanks to relatively higher hole transfer integral that links to stronger intermolecular interaction due to the presence of multiple NH???π and CH???π(py) interactions with energy close to common NH???N hydrogen bonds, as well as overall lower hole‐vibrational coupling owing to the absence of coupling of holes to low frequency modes due to better π conjugation. 相似文献
49.
50.
Summary. A novel process for the one-step chemoselective conversion of alkyl halides into carbamates as protected amines was developed
using benzyltrimethylammonium hydroxide (Triton-B) in presence of gaseous carbon dioxide. Thus, carbamate esters of different
amines were prepared in very good to excellent yields.
Present address: Institute of Organic and Biomolecular Chemistry, George–August University, 37077, G?ttingen, Germany 相似文献