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91.
α, β-Unsaturated aldehydes and Ketones when reacted with NaBr-Me3SiCl-Et3N in DMF at ambient temperature, yield silyl dienol ethers in high yields. 相似文献
92.
This work is concerned with the viscous flow due to a curved stretching sheet. The similarity solution of the problem is obtained numerically by a shooting method using the Runge-Kutta algorithm. The physical quantities of interest like the fluid velocity and skin friction coefficient are obtained and discussed under the influence of dimensionless curvature. It is evident from the results that dimensionless curvature causes an increase in boundary layer thickness and a decrease in the skin friction coefficient. 相似文献
93.
94.
D. Srinivasa Reddy P. Srinivas D. Balasubrahmanyam Javed Iqbal 《Tetrahedron letters》2007,48(26):4533-4534
The synthesis of an oxa-lipoic acid is reported here for the first time. We have achieved the synthesis of the title compound starting from commercially available acrolein using a Michael addition and Knoevenagel condensation as key reactions. 相似文献
95.
We present a quantum CNOT logic gate based on interaction of a three-level cesium atom with a two-mode electromagnetic field
in a high-Q superconducting cavity. The three-level atom acts as a control qubit and the two-mode electromagnetic field serves as a target
qubit. Presently available QED experiments make it feasible to realize the theoretical suggestion in the laboratory. We determine
the feasibility of our proposal by calculating the fidelity. 相似文献
96.
A previous study has shown that retention of magnetic particles at a model airway surface requires prohibitively strong magnetic fields. As mucus viscoelasticity is the most significant factor contributing to clearance of magnetic particles from the airway surface, mucolytics are considered in this study to reduce mucus viscoelasticity and enable particle retention with moderate strength magnetic fields. The excised frog palate model was used to simulate the airway surface. Two mucolytics, N-acetylcysteine (NAC) and dextran sulfate (DS) were tested. NAC was found to enable retention at moderate field values (148 mT with a gradient of 10.2 T/m), whereas DS was found to be effective only for sufficiently large particle concentrations at the airway surface. The possible mechanisms for the observed behavior with different mucolytics are also discussed based on aggregate formation and the loading of cilia. 相似文献
97.
Imran Mohammad Iqubal Mohammad Kashif Ahmad Sayeed Ali Javed Baboota Sanjula 《平面色谱法杂志一现代薄层色谱法》2019,32(5):393-400
JPC – Journal of Planar Chromatography – Modern TLC - A simple, sensitive, specific, rapid, and accurate high-performance thin-layer chromatographic (HPTLC) method has been developed... 相似文献
98.
Dr. Raheela Naz Prof. Qinglei Liu Dr. Waseem Abbas Dr. Muhammad Imtiaz Dr. Imran Zada Dr. Javed Ahmad Dr. Tengfei Li Prof. Jiajun Gu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(70):16054-16062
A new ternary composite of 1T-molybdenum disulfide, hexagonal tungsten trioxide, and reduced graphene oxide (M-W-rGO) is synthesized by using a one-pot hydrothermal process. The synergetic effect of 1T-MoS2 and hexa-WO3 nanoflowers improves the electrochemical performance for supercapacitors by inducing additional active sites and hexagonal tunnels, respectively, which lead to high storage capacity and easy transfer of electrolyte ions. The ternary M-W-rGO composite has a high specific capacitance of 836 F g−1 at 1 A g−1, which is nearly twice that of binary composites of M-rGO and W-rGO with high capacitance retention of 86.35 % after 3000 cycles at a high current density of 5 A g−1. This study provides a new ternary composite that can be used as an electrode material for high-performance supercapacitors. 相似文献
99.
B.V. Subba Reddy P. Sivaramakrishna Reddy B. Phaneendra Reddy J.S. Yadav Ahamad Al Khazim Al Ghamdi 《Tetrahedron letters》2013
A stereoselective total synthesis of xyolide is described employing MacMillan α-hydroxylation, Steglich esterification, and ring closing metathesis as key steps. The use of organocatalytic MacMillan α-hydroxylation to construct two of the chiral centers of the xyolide makes this approach attractive. 相似文献
100.
A variety of α-allyl-β-ketoesters (1) containing two different double bonds, undergo highly regioselective iodoenoletherification to give the titled compound (2) in excellent yields. 相似文献