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141.
S Chanda Sarmishtha Bhattacharyya Tumpa Bhattacharjee SS Ghugre Swapan Kumar Basu S Muralithar RP Singh B Mukherjee RK Bhowmik SN Ray 《Pramana》2001,57(1):175-179
The high spin states in N=80 139Pr have been investigated by in-beam γ-spectroscopic techniques following the reaction 130Te (14N, 5n) reaction at E=75 MeV, using a gamma detector array, consisting of seven 23% compton-suppressed high purity germanium detectors and a multiplicity
ball of fourteen bismuth germanate elements. Based on γ-γ coincidence data, the level scheme of 139Pr has been considerably extended up to 7.2 MeV excitation. Tentative spin-parity assignments are done for the newly proposed
levels on the basis of the DCO ratios corresponding to strong gates and the available information from the earlier light ion
experiments. 相似文献
142.
Two sets of nonlinear partial differential equations originating from two different physical situations have been combined
and a new set of nonlinear partial differential equations has been formed wherefrom the previous two sets can be obtained
as particular cases. One of the two sets of equations was obtained by Yang [1] while discussing the condition of self-duality
ofSU(2) gauge fields on Euclidean four-dimensional space. The second one was reported by Charap [2] for the chiral invariant model
of pion dynamics under tangential parametrization. Using the same type of ansatz in each case De and Ray [16] and Ray [7]
obtained physical solutions of the two sets of equations. Here exact solutions of the combined set of equations with particular
values of the coupling constants have been obtained for a similar ansatz. These solutions too are physical in nature. 相似文献
143.
Let G be a simple connected graph, and let d i be the degree of its i-th vertex. The sum-connectivity index of the graph G is defined as χ ( G ) = Σ v i v j ∈ E ( G ) ? ( d i + d j ) − 1 / 2 . We discuss the effect on χ(G) of inserting an edge into a graph. Moreover, we obtain the relations between sum-connectivity index and Randić index. 相似文献
144.
The kinetics of the oxidation of formate, oxalate, and malonate by |NiIII(L1)|2+ (where HL1 = 15-amino-3-methyl-4,7,10,13-tetraazapentadec-3-en-2-one oxime) were carried out over the regions pH 3.0–5.75, 2.80–5.50, and 2.50–7.58, respectively, at constant ionic strength and temperature 40°C. All the reactions are overall second-order with first-order on both the oxidant and reductant. A general rate law is given as - d/dt|NiIII(L1)2+| = kobs|NiIII(L1)2+| = (kd + nks |R|)|NiIII(L1)2+|, where kd is the auto-decomposition rate constant of the complex, ks is the electron transfer rate constant, n is the stoichiometric factor, and R is either formate, oxalate, or malonate. The reactivity of all the reacting species of the reductants in solution were evaluated choosing suitable pH regions. The reactivity orders are: kHCOOH > k; k > k > k, and k > k < k for the oxidation of formate, oxalate, and malonate, respectively, and these trends were explained considering the effect of hydrogen bonded adduct formation and thermodynamic potential. © 1997 John Wiley & Sons, Inc. Int J Chem Kinet 29: 225–230, 1997. 相似文献
145.
Shyam Sundar Mondal Manosree Chatterjee Ranjay K. Tiwari J.N. Behera Nripen Chanda Sourav Biswas Tanmoy Kumar Saha 《应用有机金属化学》2019,33(8)
A unique hexanuclear zinc(II) ( 1 ) and two mononuclear copper(II) ( 2 and 3 ) complexes anchored with imino phenol ligand HL 1 and HL 2 were synthesized with good yield and purity (where HL 1 = 4‐tert‐butyl‐2,6‐bis((mesitylimino)methylphenol and HL 2 = 5‐tert‐butyl‐2‐hydroxy‐3‐((mesitylimino)methyl)benzaldehyde). These complexes were characterized by utilizing various spectroscopic protocols like NMR, FTIR, UV as well as ESI‐Mass spectrometry, elemental analysis and single crystal X‐ray diffraction studies. Their potential to bind calf thymus DNA (CT‐DNA) was tested utilizing different techniques such as UV–visible and fluorescence spectroscopy. The experiment implies that they interact with CT‐DNA via non‐intercalative mode with moderate capabilities (Kb ~ 104 M?1). On the other hand, these complexes have high capabilities to quench the fluorescence of bovine serum albumin (BSA) following the static pathway. In addition, they are active catalysts for the oxidation reaction of 3,5‐di‐tert‐butylcatechol (3,5‐DTBC) to 3,5‐di‐tert‐butylquinone (3,5‐DTBQ) under aerobic condition. From the recorded EPR signals of all complexes, it has been concluded that the oxidation reaction proceeds via ligand oriented radical pathway instead of metal based redox participation. Kinetic studies using 1 – 3 indicate that it follows Michaelis–Menten type of equation with moderate to high turnover number (kcat). Apart from these aspects, complexes 1 – 3 were screened for their cytotoxic behavior towards HeLa cells (human cervical carcinoma) and found quite active with comparable IC50 values to cisplatin. 相似文献
146.
Amit Basak Subhendu Sekhar Bag Kakali Rani Rudra Jharna Barman Sumana Dutta 《ChemInform》2002,33(48):115-115
147.
The difficulty in definitively linking outcomes of managerial action to organizational outcomes has been a festering issue in organizational research. The problem arises because it is not easy to separate the distinctive contributions of managers at intermediate stages, as well as the contribution of external factors beyond the control of managers. Specifically, certain managerial actions focusing on exploratory or exploitative innovation produce an intermediate output, organizational knowledge. From this base of organizational knowledge, further management actions craft the final output that eventually faces the market test. Drawing from complexity concepts, I argue that the probability of correctly fashioning the subset of key elements in the intermediate output may be a good measure of the probability of organizational success. I use March’s iconic computational simulation model to demonstrate the merits of this principle. I model the effect of complexity on managerial intentionality towards exploratory and exploitative innovation. I elicit important insights for research and practice by comparing organizational knowledge outcomes with the outcomes for probability of organizational success, in stable and moderately turbulent environment. 相似文献
148.
Tanmoy Chanda Sushobhan Chowdhury B. Janaki Ramulu Suvajit Koley Raymond C.F. Jones Maya Shankar Singh 《Tetrahedron》2014
An operationally simple and highly atom-economic anionic quadruple domino reaction sequence for the synthesis of hexacyclic indeno-fused naphthalene/quinoline molecules having structural resemblance with the C-nor-D-homo-steroid nucleus has been developed. Promoter and solvent specificity, regioselectivity and mechanistic details were experimentally established. Catalyst concentration and solvent dependent switching of domino steps creating four new C–C bonds are discussed. 相似文献
149.
Anamalagundam Lakshmipriya Gaonkar Sumana Nagaraja Rao Suryaprakash 《Tetrahedron: Asymmetry》2017,28(10):1290-1296
2′-Amino-1,1′-binaphthalen-2-ol (NOBIN) serves as a versatile chiral solvating agent (CSA) in the presence of trifluoromethanesulfonic acid (TFMS). The formation of a ternary complex has been established by NMR, UV–Vis, fluorescence and IR studies. The mechanism of interactions among the three components in the ternary complex has been proposed and the ternary complex structures of different diastereomers have been established by DFT based theoretical calculations. The present protocol has its ubiquity not only in the analysis of the enantiomeric composition of molecules possessing diverse functionalities, but also in determining the stereospecific assignment of hydroxy acids. 相似文献
150.