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91.
92.
Rajiv T. Sawant 《Tetrahedron》2010,66(11):2010-1864
A concise high yielding enantioselective synthesis of (R)-N-Boc-2-hydroxymethylmorpholine, N-(3,4-dichlorobenzyl)(R)-2-hydroxymethylmorpholine, and (R)-benzylmorpholine has been achieved by employing proline-catalyzed asymmetric α-aminooxylation of aldehyde and palladium-catalyzed intramolecular reductive amination of azido aldehyde as the key steps. 相似文献
93.
N.D. Chaudhari D.N. Bhosale S.R. Sawant 《Journal of magnetism and magnetic materials》2010,322(14):1999-2005
Nickel zinc ferrites with generic formula, NiXZn1−XFe2O4 (with X=0.28-0.40) were synthesized by an oxalate precursor route starting with acetates to study their magnetic properties. The saturation magnetization versus temperature curves resemble those of R type ferrites. The system shows the presence of Yafet-Kittel type of spin. It is observed that magnetic moment (nB) values increase with the addition of Ni2+. The remanance ratio R tends to increase with the addition of Ni2+, which has been attributed to the increase of magnetocrystalline anisotropy constant (K1). The values of R compare well with the theoretical value (0.87). The coercive force (Hc) tends to increase with the addition of Ni2+, which has been related to the reverse domain formation. Studies on temperature variation of R and Hc reveal that these parameters are thermally insensitive, which confirms the presence of multi domain grains in the material. These observations have been supported by a.c. susceptibility studies. 相似文献
94.
Functional principal component analysis is the preliminary step to represent the data in a lower dimensional space and to
capture the main modes of variability of the data by means of small number of components which are linear combinations of
original variables. Sensitivity of the variance and the covariance functions to irregular observations make this method vulnerable
to outliers and may not capture the variation of the regular observations. In this study, we propose a robust functional principal
component analysis to find the linear combinations of the original variables that contain most of the information, even if
there are outliers and to flag functional outliers. We demonstrate the performance of the proposed method on an extensive
simulation study and two datasets from chemometrics and environment. 相似文献
95.
Sawant SN Doble M Yakhmi JV Kulshreshtha SK Miyazaki A Enoki T 《The journal of physical chemistry. B》2006,110(48):24530-24540
Langmuir-Blodgett (LB) films of the water-soluble dye phenosafranine (PS) have been prepared by its adsorption from aqueous dye solution to an arachidic acid (AA) monolayer at the air-water interface. Atomic force microscopy (AFM) images of the LB films revealed the effect of change in pH of deposition on the degree of complexation of AA with the PS dye. Well-defined circular islands and holes were observed which disappeared with the increase in pH. Polarized absorption studies indicated that the dye molecules are oriented uniaxially with their long axis titled at a constant angle to the surface normal of the LB film. Within the restricted geometry of the LB film, the PS dye was electropolymerized to form a two-dimensional film of poly(phenosafranine) sandwiched between arachidic acid layers. The film was characterized by IR spectroscopy, cyclic voltammetry, and AFM. X-ray diffraction studies reveal the presence of a layer structure in the AA-PS LB film before and after polymerization. The polymer film showed highly anisotropic electrical conductivity of ca. 10 orders of magnitude. This indicates the formation of two-dimensional polyPS layers between arachidic acid layers resulting in a layered heterostructure film having alternate conducting and insulating regions. Also, the conductivity of the polyPS prepared from LB film was found to be approximately 2.5 times higher than the conductivity of polyPS prepared by solution polymerization method. 相似文献
96.
Kushal D. Bhatte Dinesh N. Sawant Krishna M. Deshmukh Bhalchandra M. Bhanage 《Particuology》2012,10(3):384-387
A novel approach for additive free synthesis of nanocrystalline magnesium hydroxide (MH) and magnesium oxide (MgO) using microwave technique is herein reported. Use of 13-propanediol as a solvent played multiple roles circumventing the additional requirement of any extraneous species such as base and other capping agents. The prepared nanomaterials were well characterised using TEM, XRD, EDAX, Raman spectroscopy and FT-IR analysis. 相似文献
97.
Sagar P. Pathare Ravindra V. Sawant Krishnacharya G. Akamanchi 《Tetrahedron letters》2012,53(26):3259-3263
Sulfated tungstate catalyzed, green, rapid, and practical method for N-formylation of amines using formic acid under solvent-free conditions is described. This method showed improvements over the reported in terms of yield, reaction time, and chemoselectivity. 相似文献
98.
99.
Shivani Sharma Ramdas S. Pathare Antim K. Maurya Bhagyashree Goswami Vijai K. Agnihotri Devesh M. Sawant Ram T. Pardasani 《Tetrahedron letters》2017,58(40):3823-3826
A metal-/oxidant-free sustainable protocol for the synthesis of 3-sulfenylindoles based on electrophilic cyclization of 2-alkynylanilines has been developed under microwave irradiation. Herein, catalytic amount of iodine and stoichiometric amount of sulfonyl hydrazides were employed as catalyst and electrophiles respectively to induce the 5-endo-dig cyclization of 2-alkynylanilines. This strategy allows a wide substrate scope, demonstrates good functional group tolerance, utilizes easily available reagents and overcome multistep synthesis. 相似文献
100.
Yogesh S. WaghDinesh N. Sawant Pawan J. TambadeKishor P. Dhake Bhalchandra M. Bhanage 《Tetrahedron》2011,67(13):2414-2421
Pd(OAc)2/1,1′-bis(diphenylphosphino)ferrocene as an efficient, highly active catalyst for the allylation of amines, alcohols and carboxylic acids with 1-phenyl-1-propyne has been developed. The effect of various reaction parameters, such as ligand, time, solvent, temperature, metal: ligand ratio and catalyst concentration on yields of the product were investigated. The optimized procedure works well under mild operating conditions and permits rapid generation of a library for various allylated products. 相似文献