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31.
M. Krishnan Parkash Singh R. T. Thampy V. B. Gupta 《Journal of polymer science. Part A, Polymer chemistry》1974,12(2):255-264
Chlorinated poly(vinyl chloride) (CPVC) is known to have a higher softening temperature than conventional poly(vinyl chloride) (PVC). Its processability characteristics are, however, different; it has been reported that CPVC is more difficult to process. However, only limited information on the processability characteristics is available. This paper describes some studies of the flow behavior of CPVC melts in a capillary rheometer. The true melt viscosity and activation energy were determined between 190° and 210°C for a number of samples, and they appear to be related to the cohesive energy density of the samples. It was observed that melt fracture, i.e., gross distortion of the extrudate, occurs even at low shear rates in samples having a high chlorine content. This has been attributed to the relatively high pressures that have to be used, the pronounced non-Newtonian nature of the melt, and melt elasticity. It is postulated that melt elasticity could result from crosslinking at the site of the double bond which is known to be formed by dehydrochlorination. 相似文献
32.
Manganese(III) acetate mediated oxidation of aporphines to oxoaporphines is described. The developed methodology was conveniently applied for the synthesis of naturally occurring oxoaporphine alkaloids, oxoglaucine, and atheroline, starting from commercially available boldine. 相似文献
33.
Om Prakash Shiv Kumar Pushkar Singh Volker Deckert S. Chatterjee A.K. Ghosh Ranjan K. Singh 《Journal of Raman spectroscopy : JRS》2016,47(7):813-818
Interest in the synthesis of hybrid substrates for surface‐enhanced Raman scattering (SERS) has surged recently. Hereof, in the present work, a hybrid SERS substrate CuO : Mn/Ag heterojunction has been synthesised. To accomplish this, the nanostructred Ag island film and CuO : Mn nanoparticles are synthesised by vacuum thermal evaporation method and sol–gel method respectively, and thereafter, a heterojunction between the CuO : Mn and Ag is fabricated by adsorption of CuO : Mn (10‐3 m in ethanol) on Ag island film. Further, the SERS sensitivity of CuO : Mn/Ag heterojunctions has been studied by probing methyl orange. We observed that with Mn‐doping in the lattice of CuO, the SERS signal is enhanced considerably because of ferromagnetic ordering in CuO : Mn. DFT/B3LYP/6‐311 G(d, p) method is used to calculate the energy of HOMO and LUMO level of methyl orange. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
34.
Om Prakash Yadav Ram Jiwari 《Numerical Methods for Partial Differential Equations》2017,33(5):1652-1677
In this article, the authors present finite element analysis and approximation of Burgers’‐Fisher equation. Existence and uniqueness of weak solution is proved by Galerkin's finite element method for non‐smooth initial data. Next, a priori error estimates of semi‐discrete solution in norm, are derived and the convergence of semi‐discrete solution is established. Then, fully discretization of the problem is done with the help of Euler's backward method. The nonlinearity is removed by lagging it to previous known level. The scheme is found to be convergent. Positivity of fully discrete solution is discussed, and bounds on time step are discovered for which the solution preserves its positivity. Finally, numerical experiments are performed on some examples to demonstrate the effectiveness of the scheme. The proposed scheme found to be fast, easy and accurate.© 2017 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 33: 1652–1677, 2017 相似文献
35.
International Journal of Theoretical Physics - In secure multiparty quantum computation (SMQC), the multiplication is one of the fundamental operations that can be used to assemble the complex... 相似文献
36.
A configuration of reversal shear interferometer suitable for measurement of spatial coherence of high average power, large cross-section laser beam has been discussed. Ghost-less beam splitters in which unwanted multiple reflections from the surfaces have been suppressed by total internal reflection are used for beam splitting and re-combination. Advantages and drawbacks of this configuration have been discussed. 相似文献
37.
The extraction of cadmium(II), indium(III) and thallium(III) with high molecular weight amines have been studied from aqueous hydrochloric acid solutions. Using the data mutual binary separations of these three elements with high separation coefficients are proposed. Various variables like type of amine, amine concentration and organic diluent were explored to propose the best conditions of separations. 相似文献
38.
D. B. Parihar Om Prakash Indira Bajaj R. P. Tripathi K. K. Verma 《Mikrochimica acta》1971,59(3):393-398
Summary High explosives having the sameR
f
values on a thin-layer chromatogram and difficult to separate are readily resolved as their coloured -complexes with aromatic amines. After liberation from their complexes on the plate, up to 1.5 g of the explosives can be conveniently estimated at their characteristic absorption maxima.
Zusammenfassung Hochexplosive Substanzen mit gleichenR f -Werten auf Dünnschichtchromatogrammen, die sich schlecht trennen lassen, werden als gefärbte -Komplexe mit aromatischen Aminen gut voneinander getrennt. Nach Freisetzung aus den Komplexen auf der Platte können bis zu 1,5 g der Explosivstoffe bei ihrem charakteristischen Absorptionsmaximum auf übliche Weise bestimmt werden.相似文献
39.
40.
Summary The influence of ultrasonic waves at 1 MC/sec and 225 watts/cm2 power on the negatively charged manganese dioxide sol has been investigated in an atmosphere of nitrogen and thereby excluding
oxygen. The stability of the sol on exposure to ultrasonic waves is affected in a similar way as in presence of air but the
extent to which the sol gets unstable on exposure is less in the absence of oxygen than in its presence. The specific conductivity
increases but hydrogen ion concentration remains practically constant as the time of exposure increases.
The authors are thankful to the Council of Scientific and Industrial Research for the award of scholarship for this work. 相似文献
Zusammenfassung Der Einflu? von Ultraschall (1 mHz, 225 W/cm2) auf negativ geladenes Mangandioxidsol wurde unter Stickstoff unter Ausschlu? von Sauerstoff untersucht. Die Stabilit?t des Sols ist in gleicher Weise wie bei Gegenwart von Luft ver?ndert, nur wird das Sol bei Ausschlu? von Sauerstoff weniger instabil. Die spezifische Leitf?higkeit steigt mit steigender Expositionszeit, w?hrend die Wasserstoffionenkonzentration praktisch konstant bleibt.
The authors are thankful to the Council of Scientific and Industrial Research for the award of scholarship for this work. 相似文献