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991.
Roberto Longo 《Reports on Mathematical Physics》1977,12(1):119-124
Given a C1 algebra , the generator of a group of automorphisms δ, and a derivation D, we examine some situations in which δ+λD is a generator for small real λ. 相似文献
992.
T. Matsuyama H. Sakai H. Yamaoka Y. Maeda H. Shirakawa 《Solid State Communications》1981,40(5):563-565
The 129I Mössbauer effect has been applied to polyacetylene films of cis-(CHI0.23)x as prepared and cis-(CHI0.20)x led under dynamic evacuation. It has been clarified that both films contain linear I?5 and I?3 with symmetric charge population and that the fraction of I?3 increases after evacuation. The mechanism of electrical conductivity in iodine-doped polyacetylene has been discussed on the basis of the chemical form and the dynamic behavior of the anion species. 相似文献
993.
(Z)-Jasmone ,dihydrojasmone and other 3-methylcyclo=pent-2-en-1-ones are easily synthesized starting from aldehydes and 1-(2-methyl-1,3-dioxolane-2-yl)-2-nitroethane as reagent for 3-ketobutyl anion synthon. Nitro-aldol condensation is the chainlegthening reaction followed by oxidation and denitration via p-toluenesulfonylhydrazones of the corresponding -nitroke=tones. Removal of protecting groups gives 1,4-diketones which are then cyclized with alkali. 相似文献
994.
N. S. Craigie V. Roberto D. Whould 《Zeitschrift fur Physik C Particles and Fields》1982,12(2):173-176
We point out a sensitive way of analyzing the gluon polarization inside a polarized proton using hyperon production at largep T inPP collisions, by using initial and final state polarizations. 相似文献
995.
996.
997.
The effect of pressure on the melting point and volume of fusion of polyethylene was studied by high-pressure dilatometry. Starting materials were crystallized slowly from the melt under pressures of 1500, 3500, 5130 kg/cm2, and 1 atm. It has been shown that the unusual behavior observed at pressures above 4000 kg/cm2 is due to crystallization and melting of two kinds of extended-chain crystals differing in thermal stability. These are designated as ordinary extended-chain and highly extended-chain crystals, respectively. The relation between pressure P and melting temperature Tm of folded-chain, ordinary extended-chain, and highly extended-chain polyethylene was determined precisely. At pressures up to about 3000 kg/cm2, plots of P against Tm for the crystal forms have almost the same curvature and then become parallel. But at pressures above 4000 kg/cm2, ordinary extended-chain crystals show a linear increase of Tm with a constant slope of about 70 atm/deg. Curve for the highly extended-chain crystals changes in slope from 70 to 50 atm/deg at pressures between 3500 and 4300 kg/cm2, and then show a sharp increase of Tm with increasing pressure. Experiments show that the meltingpoint curve of the highly extended-chain crystals overlaps that of the ordinary extended-chain crystals at pressures below 4000 kg/cm2. Annealing experiments with folded-chain and ordinary extended-chain crystals have been made under high pressure. It is suggested that the formation of highly extended-chain crystals occurs stepwise through the formation and reorganization of ordinary extended-chain crystals from the original folded-chain crystals by a mechanism of partial melting and recrystallization at pressures above 4000 kg/cm2. 相似文献
998.
999.
T. Okada K. Fujiwara M. Maeda Y. Miyazoe 《Applied Physics A: Materials Science & Processing》1978,15(2):191-196
A guideline for the optimum design of linear wall-ablation lamps is presented with a simple empirical formula which describes
the luminescent characteristics of lamps. The absolute luminescent efficiency of the wall-ablation lamp was measured. A high-energy
dye laser with a quadruple-elliptical cylindrical cavity was constructed using these lamps, and an output energy of 23.3 J
(11.6 MW) was obtained with an overall efficiency of 0.31 %. The energy-flow diagram of this laser system was computed with
a rate-equation analysis, and the conversion efficiency from electrical input to laser output was determined. One can expect
an overall efficiency of about 2 %. 相似文献
1000.