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排序方式: 共有208条查询结果,搜索用时 906 毫秒
41.
Swapnil D. Patil R. Narasimhan R.K. Mishra 《Journal of the mechanics and physics of solids》2008,56(6):2265-2286
In this work, the effect of crack tip constraint on near-tip stress and deformation fields in a ductile FCC single crystal is studied under mode I, plane strain conditions. To this end, modified boundary layer simulations within crystal plasticity framework are performed, neglecting elastic anisotropy. The first and second terms of the isotropic elastic crack tip field, which are governed by the stress intensity factor K and T-stress, are prescribed as remote boundary conditions and solutions pertaining to different levels of T-stress are generated. It is found that the near-tip deformation field, especially, the development of kink or slip shear bands, is sensitive to the constraint level. The stress distribution and the size and shape of the plastic zone near the crack tip are also strongly influenced by the level of T-stress, with progressive loss of crack tip constraint occurring as T-stress becomes more negative. A family of near-tip fields is obtained which are characterized by two terms (such as K and T or J and a constraint parameter Q) as in isotropic plastic solids. 相似文献
42.
Temperature controlled chemoselective dehydrogenation and aromatization of tetrahydro-β-carbolines, using molecular I2 and H2O2, in DMSO solvent affords a practical access to a series of corresponding 3,4-dihydro-β-carbolines and β-carbolines respectively. This method has been successfully employed in the short synthesis of Kumujian-C, Eudistomin-U, Norharmane Harmane Harmalan and Isoeudistomin-M. 相似文献
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Gadekar Sachin P. Dipake Sudarshan S. Gaikwad Suresh T. Lande Machhindra K. 《Research on Chemical Intermediates》2018,44(12):7509-7518
Research on Chemical Intermediates - TS-1 zeolite was prepared for the synthesis of 5-arylidene-2,4-thiazolidinediones/Rhodanines in aqueous medium by incorporating titanium(IV) cations in a... 相似文献
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Das Ranjita S. Warkhade Swapnil K. Kumar Anupama Wankhade Atul V. 《Research on Chemical Intermediates》2019,45(4):1689-1705
Research on Chemical Intermediates - In the present investigation, an efficient visible light-active, graphene oxide-based zirconium oxide nanocomposite (GO–ZrO2) has been synthesized by... 相似文献
48.
Ravindra R. Shinde Dattatray Gaikwad Mazahar Farooqui 《Journal of heterocyclic chemistry》2020,57(11):3907-3917
A new series of 2-(4-(benzo[d]thiazol-5-ylsulfonyl)piperazin-1-yl)-N-substituted acetamide (5a-5k) compounds have been synthesized, and these compounds were characterized with spectral data like IR, NMR, and Mass spectroscopy. All compounds were evaluated in vitro for their efficacy as antimicrobial against Gram-positive and Gram-negative pathogenic bacterial strains such as Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa using ciprofloxacin as a standard and fungal strains like Candida albicans and Aspergillus fumigatus as compared with standard drug Clotrimazole, and Molecular docking study shows that all these compounds were having good to excellent correlation binding energy as compared with binding energy of standard drugs. 相似文献
49.
Titanium dioxide nanoparticles were prepared by a electrochemical reduction method using para-meters such as current density, solvent polarity, distance between electrodes, and concentration of stabilizers to control the size of the nanoparticles. The nanoparticles were characterized by UV-Vis spectroscopy, X-ray diffraction, scanning electron microscopy and transmission electron microsco-py, and their catalytic performance was tested for the synthesis of a series of 4-aryldiene-2-phenyl-5(4)-oxazolones from the cyclodehydration and condensation of the respec-tive aldehyde, hippuric acid and acetic anhydride. Easy availability, reusability and eco-friendliness were some prominent features of the nanocrystalline titanium dioxide catalyst. 相似文献
50.
Lingaiah Nagarapu Hanmant K. Gaikwad Rajashaker Bantu Sheeba Rani Manikonda C. Ganesh Kumar Sujitha Pombala 《Tetrahedron letters》2012,53(10):1287-1291
A series of glycosidic-pyrroloquinolinone based novel building blocks of camptothecin (2a–g) were synthesized via Lewis acid-assisted olefin cross-metathesis reaction using Ti(OiPr)4 30 mol % and 10 mol % of Grubb’s second generation catalyst with good to excellent yields. Most of these compounds exhibited significant growth inhibitory effects on all the tested cancer cell lines and three compounds (2c, 2d and 2e) showed potent cytotoxic activity. 相似文献