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991.
The magnetization process of Co/Si/Co/GaAs was studied as a function of Si-spacer layer thickness. Coercivity of Co/Si decreased with increasing Si-spacer layer thickness.The Hysteresis loop changed from two phases to a single phase with decreasing temperature and Si-spacer layer thickness. Magnetoresistance (MR) ratio in current-perpendicular-to-plane (CPP) configuration increased with decreasing Si-spacer layer thickness. 相似文献
992.
Satish Kumar Vujjini Vivekananda Reddy Mothukuri Aminul Islam Rakeshwar Bandichhor Mukkanti Kagga 《合成通讯》2013,43(24):3294-3306
Efficient and cost-effective synthesis of Zolmitriptan 1 employing Japp–Klingemann reaction and a new robust purification strategy is described. 相似文献
993.
Tetrabutylammonium tribromide (TBATB) has been found to be an efficient catalyst for the one-pot synthesis of highly substituted piperidines through a combination of 1,3-dicarbonyl compounds, aromatic aldehydes, and various amines in ethanol at room temperature. Atom economy, good yields, environmentally benign, and mild reaction conditions are some of the important features of this protocol. 相似文献
994.
995.
Ferric stearate (FeSt) Langmuir-Blodgett (LB) films have been reacted chemically with H2S gas for making iron sulphide within the organic matrix. Films, before and after the reaction with H2S, have been analyzed with the X-ray reflectivity (XRR), atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) studies. After sulphidation, more ‘pinhole’ defects form which changes the film morphology and the number of layers increases due to the rearrangement of the molecules. Formation of less ordered iron sulphide within the stearic acid multilayers after sulphidation increases the interfacial roughness that decreases the reflectivity. XPS analysis shows that polysulphide forms within the microenvironment of the FeSt LB films after reaction with H2S whereas both mono and polysulphide are produced when the reaction occurs with FeSt in bulk. 相似文献
996.
Nisha SoodBiswas Md Asraful Sekh Samir Sarkar Amitabha Basuray 《Optics Communications》2012,285(10-11):2607-2610
In this short communication we are reporting a new kind of rod lens with toric power with moderately large power difference. These rods can be directly used in coupling power from a semiconductor laser to optical fiber or in free space communication to convert the beam shape. This rod may directly be butt-jointed to the laser, which may attract many application scientists. Moreover, anamorphic power in a GRIN lens can be generated by proper selection of geometry of the substrate for ion exchange. This may lead to a new kind of optical system that needs further exploration. 相似文献
997.
1,1-Diaryl moieties are core structures in a wide range of bioactive and pharmaceutical compounds.Transition-metal catalysis is a convenient approach to accessing these invaluable compounds affording high yields and enantioselectivities.This review summarizes 1,1-diarylalkanes synthesis through transition metal catalysis.Particular focus is given to recent developments,such as reductive cross-electrophile couplings,benzylic C–H bond arylation,transformations involving metal migration,asymmetric hydrogenation of 1,1-diarylalkenes and three-component coupling reactions. 相似文献
998.
999.
Islam Md. Rashidul Chakraborty Ashok Kumar Gafur M. A. Rahman Md. Aminur Rahman Md. Hamidur 《Research on Chemical Intermediates》2019,45(4):1753-1773
Research on Chemical Intermediates - Graphitic-C3N4/TiO2 nanocomposite was prepared as a photocatalyst (PC) active under visible light (λ?≥?420 nm) by preparation of... 相似文献
1000.
M.A.A. Hamad I. Pop A.I. Md Ismail 《Nonlinear Analysis: Real World Applications》2011,12(3):1338-1346
In this paper, we discuss similarity reductions for problems of magnetic field effects on free convection flow of a nanofluid past a semi-infinite vertical flat plate. The application of a one-parameter group reduces the number of independent variables by 1, and consequently the governing partial differential equation with the auxiliary conditions to an ordinary differential equation with the appropriate corresponding conditions. The differential equations obtained are solved numerically and the effects of the parameters governing the problem are discussed. Different kinds of nanoparticles were tested. 相似文献