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61.
Mohd. Imran Ansari Ravi Shankar Mohd. Kamil Hussain Ruchir Kant Prakash R. Maulik K. Ravi Kumar K. Hajela 《Journal of heterocyclic chemistry》2011,48(6):1336-1341
Mono‐ and bis‐diaryl‐2H‐1,4‐benzothiazines were obtained in quantitative yields through silica‐supported perchloric acid catalyzed reaction cascade of double condensation and 1,4 addition of diaroylacetylenes with 2‐aminothiophenol at room temperature. The structures were confirmed by spectroscopic analyses and X‐ray crystallographic studies. J. Heterocyclic Chem., (2011) 相似文献
62.
Alireza Ansari 《Integral Transforms and Special Functions》2019,30(4):301-315
In this paper, using the Mellin transform of Wright function we derive an addition formula for the Wright function. In some special cases, addition formulas for the Hermite, Bessel and Mittag-Leffler functions are also given and the Green's function of two-dimensional time-fractional diffusion equation is presented in the whole plane. 相似文献
63.
Kohansal-Vajargah M. Ansari R. Faraji-Oskouie M. Bazdid-Vahdati M. 《应用数学和力学(英文版)》2021,42(7):999-1012
Based on the micropolar theory(MPT), a two-dimensional(2 D) element is proposed to describe the free vibration response of structures. In the context of the MPT, a 2 D formulation is developed within the ABAQUS finite element software. The user-defined element(UEL) subroutine is used to implement a micropolar element. The micropolar effects on the vibration behavior of 2 D structures with arbitrary shapes are studied. The effect of micro-inertia becomes dominant, and by considering the micropolar effects, the frequencies decrease. Also, there is a considerable discrepancy between the predicted micropolar and classical frequencies at small scales, and this difference decreases when the side length-to-length scale ratio becomes large. 相似文献
64.
Chen Jiawei Al-Homidan Suliman Ansari Qamrul Hasan Li Jun Lv Yibing 《Journal of Optimization Theory and Applications》2021,189(1):221-243
Journal of Optimization Theory and Applications - In this paper, we study robust necessary optimality conditions for a nondifferentiable complex fractional programming with uncertain data. A robust... 相似文献
65.
A lanthanum(III) complex of catechin has been synthesized and characterized by elemental analysis, molar conductance, UV-Vis spectra, infrared spectra, thermal analysis, and 1H NMR. The complex behaves as a nonelectrolyte in methanol solvent. The spectral and thermal properties of the complex are examined. A thermogravimetric (TGA) study showed the hydrated nature of the complex. 1H NMR spectra of the lanthanum and the catechin (CT) ligands measured in CD3OD-d4 also show metal ligand coordination. The lanthanum–catechin complex shows bright luminescence in methanol solution. The interaction of the complex with calf thymus DNA has been investigated by absorption and emission spectroscopic measurements. Experimental spectral results suggest CT–DNA binding with catechin complex via an intercalative mode. 相似文献
66.
In this paper, a size-dependent first-order shear deformable shell model is developed based upon the modified strain gradient theory (MSGT) for the axial buckling analysis of functionally graded (FG) circular cylindrical microshells. It is assumed that the material properties of FG materials, which obey a simple power-law distribution, vary through the thickness direction. The principle of virtual work is utilized to formulate the governing equations and corresponding boundary conditions. Numerical results are presented for the axial buckling of FG circular cylindrical microshells subject to simply-supported end conditions and the effects of material length scale parameter, material property gradient index, length-to-radius ratio and circumferential mode number on the size-dependent critical buckling load are extensively studied. For comparison purpose, the critical buckling loads predicted by modified couple stress theory (MCST) and classical theory (CT) are also presented. Results show that the size effect plays an important role for lower values of dimensionless length scale parameter. Moreover, it is observed that the critical buckling loads obtained based on MSGT are greater than those obtained based on MCST and CT. 相似文献
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68.
Arndt HD Hauschild KE Sullivan DP Lake K Dervan PB Ansari AZ 《Journal of the American Chemical Society》2003,125(44):13322-13323
A polyamide-peptide conjugate is designed which recruits sequence specifically the developmental regulator Exd to a cognate DNA site. In particular, an eight-ring hairpin polyamide (Im-Im-Py(C3H6NHR)-Py-gamma-Im-Py-Py-Py-beta-Dp) with a heptapeptide (R = Ac-Phe-Tyr-Pro-Trp-Met-Lys-Gly-) attached on a central ring was shown to induce cooperative binding of the Drosophila Hox protein cofactor Exd with a Kd of 4.4 nM in vitro, an order of magnitude more efficient than the natural Hox protein partner Ubx. The conjugate joins two sequence specific domains, one for DNA and one for the protein. This small molecule thus serves as a cooperative protein-DNA dimerizer, which mimics the natural Hox family of developmental regulators. 相似文献
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