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61.
Nonlinear Dynamics - We investigate the control of friction-induced vibration in a precision motion stage under the effect of the LuGre friction dynamics. We consider a lumped parameter model of... 相似文献
62.
Sharoni Gupta Chetna Ameta Pinki Bala Punjabi 《Journal of heterocyclic chemistry》2020,57(6):2410-2427
In the present paper, a novel and benign protocol for microwave enhanced one pot syntheses of 2,3-dihydro-1,5 benzodiazepine derivatives from substituted acetophenones, aryl-aldehydes and o-phenylene diamine using heterogeneous calcium ferrite/graphene oxide (CF/GO) nanocomposite has been reported. The catalyst was prepared by ultrasonication method and characterized by spectral and analytical techniques. The CF/GO nanocomposite was employed for environmentally benign synthesis of 2,3-dihydro-1,5 benzodiazepines. The synthesized benzodiazepine derivatives were screened for their antimicrobial activities against various bacteria and fungi. The present synthetic strategy offered several advantages such as excellent yields in short span of time, simple modus operandi, ease of isolation and purification of products, simple recovery and reusability of the catalyst. A tentative mechanism for synthesis of 2,3-dihydro-1,5 benzodiazepine using CF/GO nanocatalyst has also been proposed. 相似文献
63.
Crystallography Reports - The communication deals with the eco-friendly synthesis and X-ray crystal structure of an organic carbonitrile, namely... 相似文献
64.
65.
Crystallography Reports - Remotely operated Czochralski puller, Automatic Crystal Puller System (ACPS) with a translation nano-resolution of 20 nm, is designed and developed for high quality... 相似文献
66.
67.
The rotational excitation of the H2 and N2 molecules from (J→J+2,J=0) and (J→J+2,J=1) states by electron impact is studied, in the framework of the regional-plane-wave approximation. The empirical cut-off
parameterρ, involved in these calculations, is varied to give the best fit to the experimental data of Srivastava and co-workers. 相似文献
68.
This paper explores the well-known modified due date (MDD) rule for minimizing total tardiness on a single machine and shows that it has a decomposition structure. Based on this finding, we propose a decomposition heuristic and draw parallels to the famous optimal decomposition algorithm. We demonstrate that the MDD rule and the decomposition algorithm have striking similarities. We also discuss the key differences between these procedures. Finally, we present a sufficient condition under which the MDD rule is optimal and conclude the paper with some directions for future research. 相似文献
69.
The coefficient of variation is an important parameter in many physical, biological and medical sciences. In this paper we study the estimation of the square of the coefficient of variation in a weighted inverse Gaussian model which is a mixture of the inverse Gaussian and the length biased inverse Gaussian distribution. This represents a rich family of distributions for different values of the mixing parameter and can be used for modelling various life testing situations. The maximum likelihood as well as the Bayes estimates of the parameters are obtained. These estimates are used to derive the estimates of the square of the coefficient of variation of the model under study. Several important data sets are analysed to illustrate the results. © 1996 John Wiley & Sons, Ltd. 相似文献
70.
Bimetallic SCN ligand based single crystals of manganese mercury thiocyanate (MMTC), cadmium mercury thiocyanate (CMTC) and zinc cadmium thiocyanate (ZCTC) are grown by slow solvent evaporation technique. The growth mechanism and surface features are investigated by optical microscopic techniques such as scanning electron microscopy (SEM) and atomic force microscopy (AFM). The laser induced surface damage measurements were carried out using a Q-switched Nd:YAG laser at 1064 nm with laser beam of 1.0 Hz and pulse duration 25 ps. The laser damage threshold values of MMTC, CMTC and ZCTC are found to be 15.9, 22.9 and 19.7 GW/cm2, respectively. The SEM analysis of MMTC reveals the formation of elongated dendrite growth pattern caused by the fluctuations of Mn and Hg metal ligands when thiocyanate (SCN) bridges them. The etching study indicates the occurrence of different types of etch pit patterns like terraced triangles, pillars, pyramids and rods. The AFM images confirm the formation of three major hillocks with cavities in MMTC. The measured roughness values for CMTC crystal are very much lower than that of MMTC. 相似文献