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排序方式: 共有338条查询结果,搜索用时 265 毫秒
1.
Rathore Vikas Tiwari Budhi Sagar Nema Sudhir Kumar 《Plasma Chemistry and Plasma Processing》2022,42(1):109-129
Plasma Chemistry and Plasma Processing - The present study has been carried to investigate the interaction and effect of plasma activated water (PAW) on pea seeds. PAW is produced with the... 相似文献
2.
Dispersion relations have been obtained on the basis of linear response theory for helicon waves propagating parallel to a magnetic field applied along the axis of a superlattice. Numerical applications have been made to a Kronig-Penney model and the preliminary results clearly indicate nonlocal effects. 相似文献
3.
Anirudh Pradhan Sudhir Kumar Srivastav Kanti R. Jotania 《Czechoslovak Journal of Physics》2004,54(2):255-272
Some cylindrically symmetric inhomogeneous viscous-fluid cosmological models with electromagnetic field are obtained. To get
a solution a supplementary condition between metric potentials is used. The viscosity coefficient of bulk viscous fluid is
assumed to be a power function of mass density. Without assuming anyad hoc law, we obtain a cosmological constant as a decreasing function of time. The behaviour of the electromagnetic field tensor
together with some physical aspects of the model are also discussed. 相似文献
4.
Sudhir Thattey 《Annalen der Physik》1991,503(5):353-361
A theory, that is an initial step towards bridging the gap between Lorentz and Dirac theories of electrons, is presented. An electromagnetic Lagrangian density is postulated, such that, the theory can be cast into a form, similar to Dirac theory. Electromagnetic interpretation of conserved currents, and of usual bilinear covariants in the Dirac theory, is obtained. A counterpart of Abraham-Lorentz equation, with oscillatory solutions is derived. Self-energy of electrons is expressed in terms of their self-potentials and self-currents. 相似文献
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7.
B. N. Achar G. M. Fohlen J. A. Parker 《Journal of polymer science. Part A, Polymer chemistry》1983,21(1):111-120
The reactions of 4-aminophthalonitrile (APN) with 3,3′,4,4′-benzophenone tetracarboxylic dianhydride (BPTDA), and with 1,2,3,4-benzenetetracarboxylic dianhydride (PMDA) have been studied to optimize the conditions for the synthesis of monomeric thermosetting bisphthalonitrile compound. Suitable procedures for the synthesis of the two monomers are presented. Elemental analyses, IR spectra, dynamic thermogravimetric analyses, differential scanning calorimetry, 1H-NMR, and mass spectral studies have been used to characterize these compounds. Preliminary observations show that these materials can be polymerized to give high-temperature-resistant materials. 相似文献
8.
B. N. Achar G. M. Fohlen J. A. Parker 《Journal of polymer science. Part A, Polymer chemistry》1983,21(4):1025-1032
Thermally stable poly(metal phthalocyanine)imide copolymers were prepared with metal(11) 4,4′,4″,4? -phthalocyanine tetraamines, 4,4′ -diamino diphenyl ether, and 3,3′,4,4′ -benzophenone tetracarboxylic dianhydride. Variables such as molar concentrations of the reagents, solvents, and temperature were investigated to optimize the conditions of the polymerization. Inherent viscosity, and infrared (IR) spectral and thermogravimetric analysis (TGA) studies were done to characterize the polymers. These polymers are stable and thier decomposition temperatures both in air and nitrogen are greater than 500°C. Their char yields at 800°C in nitrogen varied between 60 and 76%, depending on the type and concentrations of the metal phthalocyanine tetraamines. These polymers can be used to produce heat-stable films, fibers, varnishes, and adhesives. 相似文献
9.
B. N. Achar G. M. Fohlen J. A. Parker 《Journal of polymer science. Part A, Polymer chemistry》1983,21(2):589-597
The thermal reactions of pure metal(11) 4,4′,4″,4′″-phthalocyanine-tetracarboxylic acids of copper, cobalt, and nickel at 350–400°C in vacuum have been studied using Fourier transform infrared spectrometry, gas chromatography, and mass spectrometry. Based on these observations, novel in situ reactions for the synthesis of heat-resistant phthalocyanine “sheet” polymers are described. The poly(metal phthalocyanine) polymers of copper, cobalt, and nickel so synthesized have been characterized by elemental analysis, infrared spectroscopy, and dynamic thermogravimetric analysis. The most noteworthy property of these polymers is their extreme resistance to heat in an anaerobic atmosphere and their high char yields (89–93%) at 800°C in a nitrogen atmosphere. 相似文献
10.
Reduction and subsequent aggregation of silver ions in the presence of various chelating agents such as trans-1,2-diaminocyclohexanetetraacetic acid (DCTA) 1,2-propylenediaminetetraacetic acid (PDTA), diethylenetriaminepentaacetic acid (DTPA), and triethylenetetraaminehexaacetic acid (TTHA) have been studied by pulse radiolysis. Rate constants of formation and transient absorption spectra for the ligand-complexed Ag(0) and Ag(2)(+) have been determined. The redox potential of Ag(+)(L)/Ag(0)(L) becomes more negative than that of Ag(+)/Ag(0). Growth and reactivity of silver clusters were also studied in the presence of methyl viologen (MV(2+)). The kinetics of formation of the MV(+*) radical, produced by the same pulse as in the case of silver atoms, confirms the catalytic electron transfer toward super critical silver clusters in the presence of ligands. The results suggest that catalytic electron transfer activity of silver clusters depends on the ligand. 相似文献