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91.
A chiral 1,3-diol with a benzyl backbone has been used for the asymmetric oxidation of sulfides to sulfoxides. Moderate to good yields and enantioselectivity (upto 87% ee) have been observed.  相似文献   
92.
CAN-catalyzed reaction of Betti bases with indoles under microwave irradiation gives 3-(α,α-diarylmethyl)indoles. Better yield of the products, especially when one of the aryl ring is phenol were achieved. The reaction is performed in solvent-free condition. The antibacterial studies of the synthesized compounds were performed and some of the compounds showed good activity against Methicillin-resistant Staphylococcus aureus bacteria.  相似文献   
93.
Journal of Thermal Analysis and Calorimetry - Efficient incorporation of polar monomers in polyolefin can lead to many desirable properties in the parent chain. Herein, we report the synthesis of...  相似文献   
94.
We investigated the antioxidant properties of iron oxide particles. Particles of different sizes were synthesized and their antioxidant potency was investigated by using an in vitro system. The antioxidant capacity assay was done via a modified DPPH method for insoluble solid materials. The percentages of DPPH scavenging were calculated for iron oxide particles. The particles were found to show antioxidant potency. The DPPH scavenging increases with decrease in particle size.  相似文献   
95.
This paper contains the plasma maser interaction between high frequency nonresonant whistler R-mode and low frequency resonant ion acoustic mode in a relativistic plasma. It shows that the whistler R-mode grows through the plasma maser interaction between the relativistic electrons and the ion acoustic fluctuation.   相似文献   
96.
D K Choudhury  A Saikia 《Pramana》1990,34(1):85-86
We show that the assumptions of factorizability of the structure functionF(x, t) inx andt and the equality oft evolution of the singlet and gluon distributions are not necessary to obtain the approximate solutions of Altarelli-Parisi equations derived by us recently.  相似文献   
97.
A study of Pentacene OTFTs using La2O3 as gate insulator is presented. The device characteristics were studied and analyzed. The OTFTs exhibit p-type conductivity with field effect mobility 6.5 × 10−8 m2/V.s, ON/OFF ratio 1.4 × 102, sub-threshold swing 2 mV/decade and hole concentration 4.5 × 1017 cm−3. The SEM and XRD analysis on the semiconductor film are also reported.  相似文献   
98.
We study the deterministic dynamics of a periodically driven particle in the underdamped case in a spatially symmetric periodic potential. The system is subjected to a space-dependent friction coefficient, which is similarly periodic as the potential but with a phase difference. We observe that frictional inhomogeneity in a symmetric periodic potential mimics most of the qualitative features of deterministic dynamics in a homogeneous system with an asymmetric periodic potential. We point out the need of averaging over the initial phase of the external drive at small frictional inhomogeneity parameter values or analogously low potential asymmetry regimes in obtaining ratchet current. We also show that at low amplitudes of the drive, where ratchet current is not possible in the deterministic case, noise plays a significant role in realizing ratchet current.  相似文献   
99.
An efficient catalyst PdNPs decorated on Montmorillonite K 10 is prepared by simply stirring Pd(OAc)2 in methanol at room temperature without using any external reducing agent. The catalyst shows excellent activity for Suzuki Miyaura type cross coupling reaction between aryl diazonium salt and arylboronic acid under ligand and base free reaction conditions within short reaction time. The main advantage of this methodology is the easy synthesis of heterogeneous PdNPs @ Mont K 10 catalyst in a mild condition without using any reducing agent or additive and the catalyst is very efficient for biaryl synthesis. The catalyst is well characterized by SEM, EDX, TEM, BET, Powder XRD, TGA, DSC etc. The reaction pathway is greener with aqueous reaction medium, base free reaction condition, room temperature and reusable heterogeneous catalyst.  相似文献   
100.
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