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171.
Exact solutions, including the periodic travelling and non-travelling wave solutions, are presented for the nonlinear Klein-Gordon equation with imaginary mass. Some arbitrary functions are permitted in the periodic non-travelling wave solutions, which contribute to various high dimensional nonlinear structures. 相似文献
172.
Kinetics of vinyl polymerization initiated by the redox system thiourea-Mn3+ were investigated in the temperature range 30–40°C in sulfuric acid, and the rates of polymerization Rp and disappearance of Mn3+ have been measured. The effect of certain water-miscible organic solvents and anionic surfactant on the rates of polymerization was investigated. A mechanism involving the formation of a complex between Mn3+ and thiourea whose decomposition yields the initiating free radical with the polymerization terminated by mutual intraction of growing radicals is suggested. 相似文献
173.
The kinetics of the aqueous polymerization of acrylonitrile initiated by the chromic acid-1-propanol redox system was investigated under a nitrogen atmosphere. The rates of polymerization and the disappearance of Cr(VI) were measured. Chromic acid alone did not initiate the polymerization under deaerated and undeaerated conditions. Water-miscible organic solvents and neutral salts depress both the rate and the conversion. On the basis of the experimental observations of the dependence of the rate of polymerization Rp and the rate of disappearance of Cr(VI)-Rm on various variables, a suitable kinetic scheme was proposed and various rate and energy parameters evaluated. 相似文献
174.
Arun K. Roy Samuel Pattnaik Rajani K. Samal Padma L. Nayak 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(8):1241-1249
The polymerization of acrylonitrile initiated by the redox system K2S2O8-citric acid catalyzed by Ag+ ion has been studied over the temperature range 35–50°C. The rate of polymerization is proportional to the square root of peroxydisulfate concentration. The initial rate increases with increasing citric acid concentration, but at relatively higher concentration of citric acid the rate decreases. The rate of polymerization also increases with increasing monomer concentration and temperature. The overall activation energy calculated from the Arrhenius plot was found to be 4.6 kcal/mole. On the basis of the observation, a suitable kinetic scheme has been proposed for the reaction. 相似文献
175.
Solid state ionic conductors are important from an industrial viewpoint. A variety of such conductors have been found. In
order to understand the reasons for high ionic conductivity in these solids, there have been a number of experimental, theoretical
and computational studies in the literature. We provide here a survey of these investigations with focus on what is known
and elaborate on issues that still remain unresolved. Conductivity depends on a number of factors such as presence of interstitial
sites, ion size, temperature, crystal structure etc. We discuss the recent results from atomistic computer simulations on
the dependence of conductivity in NASICONs as a function of composition, temperature, phase change and cation among others.
A new potential for modelling of NASICON structure that has been proposed is also discussed.
Dedicated to Prof J Gopalakrishnan on his 62nd birthday. 相似文献
176.
Neugebauer U Pellegrin Y Devocelle M Forster RJ Signac W Moran N Keyes TE 《Chemical communications (Cambridge, England)》2008,(42):5307-5309
Two novel polyarginine labelled ruthenium polypyridyl dyes are reported, one conjugated to five, (Ru-Ahx-R5), and one to eight arginine residues, (Ru-Ahx-R8); both complexes exhibit long-lived, intense, and oxygen-sensitive luminescence; (Ru-R8) is passively, efficiently and very rapidly transported across the cell membrane into the cytoplasm without requirement for its permeablisation. 相似文献
177.
Hejmadi Gopalakrishna Gadiyar Ramanathan Padma 《Czechoslovak Mathematical Journal》2018,68(4):1115-1124
We connect the discrete logarithm problem over prime fields in the safe prime case to the logarithmic derivative. 相似文献
178.
Subasini Lenka Padma L. Nayak Anil P. Das Surendra N. Mishra 《Journal of polymer science. Part A, Polymer chemistry》1985,23(6):1615-1620
The graft copolymerization of methyl methacrylate onto natural rubber (NR) is investigated using potassium peroxydiphosphate as the initiator. The rate of grafting is determined by varying monomer concentration, peroxydiphosphate concentration, and temperature. The graft yield increased with an increase in monomer concentration up to 1.4082M/L and thereafter the graft yield decreases. The graft yield increases significantly with an increase of peroxydiphosphate concentration up to 150 X 10-1M/L and thereafter the graft yield decreases. The grafting reaction is temperature dependent. A suitable kinetic scheme is proposed and the rate equation is evaluated. 相似文献
179.
Subasini Lenka Padma L. Nayak 《Journal of polymer science. Part A, Polymer chemistry》1987,25(6):1563-1568
The kinetics of polymerization of acrylic acid initiated by Cr6+-thiourea, Cr6+-thioacetamide, Cr6+-2-aminoethane thiol, Cr6+-cysteine, and Cr6+-thioglycollic acid have been studied at 30, 35, and 40°C in nitrogen. The rates of polymerization were measured. Chromic acid alone did not initiate the polymerization under deaerated and un-deaerated conditions. On the basis of the experimental observation of the dependence of the rate of polymerization Rp on various variables, a suitable kinetic scheme is proposed. 相似文献
180.
Krishnamoorthy Kavithaa Sundaravadivelu Sumathi Palghat Raghunathan Padma 《Journal of Cluster Science》2017,28(4):2057-2073
The recent focus and development of nanotechnology in medicine is countless, which involves diagnostic, therapeutic and preventive systems for various diseases. Nanoparticles have received much attention due to their uses in cancer therapy. The current study focused on the synthesis of baicalein loaded iron oxide nanoparticles and their efficacy against triple negative breast cancer (TNBC) MDA-MB-231. The electron microscopic analysis reveals that the particles were internalized with the various sub cellular regions of selected cancer cells. Further flow cytometric analysis of mitochondrial membrane potential using JC-1 staining showed that significant aggregates were found in the cells treated with baicalein loaded iron oxide nanoparticles, which, in turn, implies momentous mitochondrial membrane potential loss that occurs. Similarly apoptotic and anti-apoptotic gene expression pattern showed that baicalein loaded iron oxide nanoparticles were upregulates the apoptotic genes like Bad, Bax, GADD45 and PARP cleavage in a dose dependant manner. Detailed kit based flowcytometric analysis also reveals that the above findings were significant in the focused field, it is apparent that nano conjugates have the ability to induce apoptosis, DNA damage and cell cycle arrest and decrease the rate of cell proliferation in TNBC cells. 相似文献