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361.
Sharma U Verma PK Kumar N Kumar V Bala M Singh B 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(21):5903-5907
Iron phthalocyanine with iron sulfate has been successfully applied for high chemo- and regioselective reduction of aromatic nitro compounds to give the corresponding amines in a green solvent system without using any toxic ligand. The catalytic systems were also compatible with a large range of other reducible functional groups, such as keto, acid, amide, ester, halogen, lactone, nitrile, N-benzyl, O-benzyl, hydroxy, and heterocycles. In the present study, dinitro compounds have been regioselectively reduced to the corresponding amines with high yield. In most of the cases the conversion and selectivity was greater than 99% as determined by GC-MS analysis. 相似文献
362.
363.
Hepatitis C virus (HCV) infection is a global health threat and current therapies warrant the need for novel HCV therapies. Several synthetic analogs targeting HCV serine protease and RNA-dependent RNA polymerase have entered clinical development. To investigate the novel HCV NS5B RdRp polymerase inhibitor, screening of a designed data set consisting of benzimidazole analogs by the FlexX docking approach was performed. Binding interactions at the active sites (PDB ID: 2DXS) were evaluated leading to the rationalization of further synthesis and evaluation procedures. 相似文献
364.
A multivariate ultrastructural measurement error model is considered and it is assumed that some prior information is available in the form of exact linear restrictions on regression coefficients. Using the prior information along with the additional knowledge of covariance matrix of measurement errors associated with explanatory vector and reliability matrix, we have proposed three methodologies to construct the consistent estimators which also satisfy the given linear restrictions. Asymptotic distribution of these estimators is derived when measurement errors and random error component are not necessarily normally distributed. Dominance conditions for the superiority of one estimator over the other under the criterion of Löwner ordering are obtained for each case of the additional information. Some conditions are also proposed under which the use of a particular type of information will give a more efficient estimator. 相似文献
365.
Suk Hun Lee Kunyoung Kim Yeong Uk Jeon Amit Kundu Prasanta Dey Jong Yeon Hwang Neeraj Kumar Mishra Hyung Sik Kim In Su Kim 《Tetrahedron letters》2019,60(34):150974
The synthesis of 3,3′-bis-7-indolylmethane derivatives is important for their further development as pharmaceutical compounds and other synthetic purposes. Herein, we describe the zinc- or acid-mediated cross-coupling reaction of 7-azaindoles with aldehydes, such as paraformaldehyde, alkyl aldehydes, aryl aldehydes, enal, and α-ketoaldehyde, providing the corresponding C3-linked bis-7-azaindole derivatives, which are a crucial class towards the development of novel bioactive compounds. High levels of site selectivity and functional group tolerance were observed. Synthesized 3,3′-bis-7-azaindole derivatives were evaluated against human breast adenocarcinoma cells (MCF-7) and human ovarian carcinoma cells (SKOV-3), respectively. Notably, compounds 3s and 4e displayed promising anticancer properties competitive with anticancer doxorubicin as a positive control. 相似文献
366.
Neeraj K. Jaiswal 《Solid State Communications》2011,151(20):1490-1495
The size dependent electronic properties of armchair graphene nanoribbons (AGNR) with Ni doped atoms have been investigated using spin-unrestricted density functional theory. We predict antiferromagnetic (AFM) ground states for Ni-termination and one edge Ni-doping. The computed formation energy reveals that one edge Ni-terminated AGNR are energetically more favourable as compared to pristine ribbons. One edge substitutional doping is energetically more favourable as compared to centre doping by ∼1 eV whereas both edge doping is unfavourable. The bond length of substitutional Ni atoms is shorter than that of Ni adsorption in GNR, implying a stronger binding for substitutional Ni atoms. It is evident that binding energy is also affected by the coordination number of the foreign atom. The results show that Ni-interaction perturbs the electronic structure of the ribbons significantly, causing enhanced metallicity for all configurations irrespective of doping site. The band structures reveal the separation of spin up and down electronic states indicating towards the existence of spin polarized current in Ni-terminated and one edge doped ribbons. Our calculation predicts that AGNR containing Ni impurities can play an important role for the fabrication of spin filters and spintronic devices. 相似文献
367.
Mousa J. Huntul Mohammad Tamsir Neeraj Dhiman 《Numerical Methods for Partial Differential Equations》2023,39(2):848-865
The aim of this work is to identify numerically, for the first time, the time-dependent potential coefficient in a fourth-order pseudo-parabolic equation with nonlocal initial data, nonlocal boundary conditions, and the boundary data as overdetermination condition. This problem emerges significantly in the modeling of various phenomena in physics and engineering. From literature we already know that this inverse problem has a unique solution. However, the problem is still ill-posed by being unstable to noise in the input data. For the numerical realization, we apply the quintic B-spline (QB-spline) collocation method for discretizing the pseudo-parabolic problem and the Tikhonov regularization for finding a stable and accurate solution. The resulting nonlinear minimization problem is solved using the MATLAB subroutine lsqnonlin. Moreover, the von Neumann stability analysis is also discussed. 相似文献
368.
Bhattacharya Pronaya Tanwar Sudeep Bodkhe Umesh Kumar Ashwani Kumar Neeraj 《Wireless Personal Communications》2022,127(3):1943-1983
Wireless Personal Communications - In this paper, the authors propose a secure and trusted energy trading (ET) scheme for electric vehicles (EVs) for vehicle-to-anything (V2X) ecosystems. The... 相似文献
369.
Journal of Thermal Analysis and Calorimetry - A numerical study has been carried out on the spiral capillary tube for the CO2 transcritical cycle. The model is based on the basic principles of... 相似文献
370.
Kumar Upendra Navaneet Shreyshi Kumar Neeraj Pandey Subhash Chandra 《Wireless Personal Communications》2020,114(3):2493-2510
Wireless Personal Communications - Internet of Things (IoT) involves all the surrounding with smart devices to Internet and has been gaining more recognition because it provides substantial... 相似文献