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91.
Kouichi Yamaguchi Takeshi Wada Shinsaku Maruyama Masaaki Takehisa 《Journal of Polymer Science.Polymer Physics》1973,11(8):1573-1584
The molecular weight distribution of polyethylene produced by radiation was calculated according to a kinetic scheme. The calculated molecular weight distribution was compared with the results deduced from gel-permeation chromatography. The observed distribution curve from GPC was broader and showed a lower degree of polymerization than the calculated one. Discrepancies between observed and calculated curves can be explained if the polymer contains nonsteady-state products and if the reaction mechanism includes chain transfer to dead polymer. By this reaction long-chain branching would occur. Several long-chain branches per polymer molecule were indeed found, as inferred from solution properties. 相似文献
92.
Takeda Y Yoshino T Uoto K Terasawa H Soga T 《Chemical & pharmaceutical bulletin》2002,50(10):1398-1400
A new method for the synthesis of 7-deoxytaxane analogues has been established through hydrogenation of Delta(6,7)-taxane derivatives. Among several catalysts examined, Pd-C was found to be a most effective catalyst for the preparation of target compound. 相似文献
93.
Real-root property of the spectral polynomial of the Treibich–Verdier potential and related problems
Zhijie Chen Ting-Jung Kuo Chang-Shou Lin Kouichi Takemura 《Journal of Differential Equations》2018,264(8):5408-5431
We study the spectral polynomial of the Treibich–Verdier potential. Such spectral polynomial, which is a generalization of the classical Lamé polynomial, plays fundamental roles in both the finite-gap theory and the ODE theory of Heun's equation. In this paper, we prove that all the roots of such spectral polynomial are real and distinct under some assumptions. The proof uses the classical concept of Sturm sequence and isomonodromic theories. We also prove an analogous result for a polynomial associated with a generalized Lamé equation, where we apply a new approach based on the viewpoint of the monodromy data. 相似文献
94.
Proposition of a nanoscale collider experiment to examine the loss of visibility due to entanglement
Kouichi Toyoshima Takasi Endo Yutaka Hirayoshi 《Czechoslovak Journal of Physics》2006,56(12):1361-1366
Monochromatic and point-like source which emits a particle beam without wave-like property is proposed. Such a source can
be realized by taking halves of entangled pairs. Experimental feasibility to realize such a source is discussed in detail. 相似文献
95.
The presented work provides baseline data on the existing airborne conditions in the Miyagi Museum of Art in Sendai, Japan, during the summer of 2000. The chemical composition, size and indoor and outdoor origin of the suspended particulate matter were identified using a number of advanced X-ray techniques, such as Electron Probe X-Ray Microanalysis (EPXMA) and Energy Dispersive X-Ray Fluorescence Analysis (EDXRF). Our results, to the best of our knowledge, represent the first detailed study of the chemical nature of the indoor particulate matter in a Japanese museum and, as such, may contribute to future improvements of the air quality inside museums and to the lasting conservation of works of art. 相似文献
96.
Kouichi Kawai 《Journal of fluorine chemistry》2005,126(6):956-961
Synthetic utilities of microreactor for the synthesis of fluorinated materials are described. In particular, synthesis of silylenol ether of 4,4,4-trifluorobutan-2-one and its synthetic application at room temperature. Further, nitroaldol reactions and Michael addition reaction in microreactor are convenient ways for the syntheses of difluoromethylated materials. 相似文献
97.
Nakagawa K Ikota N Anzai K 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,69(5):1384-1387
We investigated the sucrose radical-production cross-section induced by heavy-ion irradiation. L-alanine was also used in order to compare radical yield and cross-section. The stable free radicals after irradiation were analyzed by electron paramagnetic resonance (EPR). The radical yield obtained by the irradiated samples had a logarithmic correlation with the LET (linear energy transfer). Quantitative EPR analyses showed that radical productions for sucrose and L-alanine vary both by different particle irradiation and the LET under the same absorbed dose. Furthermore, the cross-sections of radical productions for samples were calculated. Both cross-sections for C ions irradiation under LET 30 keV/microm at 50 Gy dose were approximately 3.0x10(-9) microm(2), taking account of the molecular areas of the samples. The values of the cross-sections imply that multiple ionizing particles involve producing stable radicals. 相似文献
98.
99.
Kuroda A Ishihara T Takeshige H Asakura K 《The journal of physical chemistry. B》2008,112(4):1163-1169
Water-repellent and self-cleaning properties of lotus leaves are considered to be due to its double roughness structure, protrusion structure (approximately 20 microm) and hairy structure (0.2-1.0 microm). In this study, attempts to fabricate a spatially periodic double roughness structure by two far-from-equilibrium self-organization phenomena, a directional viscous fingering and a spinodal dewetting, were made. A mixture of an octylsilyl titanium dioxide particle having an average diameter of 35 nm suspended in volatile silicone, decamethyl cyclopentasiloxane, and octyl p-methoxycinnamate was spread on a glass plate by dragging an applicator across the top. Formation of a stripe pattern parallel to the direction of dragging, called directional viscous fingering, was sometimes observed. Influences of spreading conditions on the pattern formation were analyzed. In addition, attempts were made to apply the stripe pattern formation to the preparation of a water repellent surface. We have succeeded in preparing a highly water-repellent surface by immersing a glass plate, on which a spatially periodic stripe pattern having a characteristic wavelength of 200-700 microm was formed, in water, after the completion of evaporation of decamethyl cyclopentasiloxane. In this case, dewetting patterns having a characteristic wavelength at around 5 microm were formed at the bottom part of the stripe patterns. Neither the surface on which only the mesoscopic spatially periodic stripe pattern was formed nor the one on which only the microscopic dewetting pattern was formed showed high water-repellent properties, indicating that the coexistence of the two different scales of patterns increased the water-repellent properties of the hydrophobic surface. 相似文献
100.