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1.
Aqueous solution of potassium persulfate converts water-insoluble carboxylic acids in ether (or dichloromethane), to peracids in a yield of 80–90% under the catalytic influence of benzyltriethylammonium chloride (BTEAC) or polyethyleneglycol (PEG-400). The reaction is further catalyzed kinetically in presence of a sulfonated polymer. 相似文献
2.
A.J. ChoudhuryS.A. Barve Joyanti Chutia A.R. PalR. Kishore JagannathM. Pande D.S. Patil 《Applied Surface Science》2011,257(20):8469-8477
Hexamethyldisiloxane (HMDSO) films have been deposited on bell metal using radiofrequency plasma assisted chemical vapor deposition (RF-PACVD) technique. The protective performances of the HMDSO films and their water repellency have been investigated as a function of DC self-bias voltage on the substrates during deposition. Plasma potential measurements during film deposition process are carried out by self-compensated emissive probe. Optical emission spectroscopy (OES) analyses of the plasma during deposition reveal no significant change in the plasma composition within the DC self-bias voltage range of −40 V to −160 V that is used. Raman and X-ray photoelectron spectroscopy (XPS) studies are carried out for film chemistry analysis and indicate that the impinging ion energy on the substrates influences the physio-chemical properties of the HMDSO films. At critical ion energy of 113 qV (corresponding to DC self-bias voltage of −100 V), the deposited HMDSO film exhibits least defective Si-O-Si chemical structure and highest inorganic character and this contributes to its best corrosion resistance behavior. The hardness and elastic modulus of the films are found to be bias dependent and are 1.27 GPa and 5.36 GPa for films deposited at −100 V. The critical load for delamination is also bias dependent and is 11 mN for this film. The water repellency of the HMDSO films is observed to be dependent on the variation in surface roughness. The results of the investigations suggest that HMDSO films deposited by RF-PACVD can be used as protective coatings on bell metal surfaces. 相似文献
3.
4.
By reexamining the analysis of Basu and Biswas, based on the stereographic projection method of Fock and Levy, it is shown
that the general solution of the Wick-Cutkosky model in the instantaneous approximation, hitherto unreported, involves only
one quantum number; this is contrasted with the well-known solution which involves two quantum numbers, but for which the
spectrum is degenerate with respect to one of them. The latter situation is shown to hold under a rather special circumstance. 相似文献
5.
Mark S. Friedrichs Peter Eastman Vishal Vaidyanathan Mike Houston Scott Legrand Adam L. Beberg Daniel L. Ensign Christopher M. Bruns Vijay S. Pande 《Journal of computational chemistry》2009,30(6):864-872
We describe a complete implementation of all‐atom protein molecular dynamics running entirely on a graphics processing unit (GPU), including all standard force field terms, integration, constraints, and implicit solvent. We discuss the design of our algorithms and important optimizations needed to fully take advantage of a GPU. We evaluate its performance, and show that it can be more than 700 times faster than a conventional implementation running on a single CPU core. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2009 相似文献
6.
Aftab Pande 《Journal of Number Theory》2009,129(1):15-27
We use a method of Buzzard to study p-adic families of Hilbert modular forms and modular forms over imaginary quadratic fields. In the case of Hilbert modular forms, we get local constancy of dimensions of spaces of fixed slope and varying weight. For imaginary quadratic fields we obtain bounds independent of the weight on the dimensions of such spaces. 相似文献
7.
8.
Summary The Ricci identities have been established by C.I. Ispas [1] and H. Rund [2] in a Finsler space. Here we shall discuss some
identities based on the principle of mathematical induction [3], [4]. 相似文献
9.
Girish Chandra Pande 《Applied Scientific Research》1965,11(1):205-212
Summary The effect of uniform high suction on the steady flow of conducting viscous liquid due to a rotating disc, in the presence of a transverse magnetic field is considered. Series solutions for velocity components are obtained in descending powers of the suction parameter (a). The solutions, thus obtained, are valid for small values of m (= B
0
2
/). Tables for displacement thickness, momentum thickness, and velocity components are given for different values of a and m. 相似文献
10.
Summary The protonation constants of several metal extractants, especially hydroxamic acids have been determined by a solvent extraction method. The influence of the acidity on the solubility and the distribution ratio has been studied. A plot correlates the protonation behaviour of these metal extractants with the Hammett Acidity Function, Ho. The protonation constant is useful to explain the acid catalysed hydrolysis rate of these metal extractants and to determine the extraction coefficients of their metal chelates. 相似文献