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101.
The purpose of our work is to control the interfacial bonds between PVC and NBR using the ammonium salts of triazine thiols and dithiodimorpholine (DTDM) and thereby reveal the relation between the interfacial bonds and the final mechanical properties of products. In the experimental work a two-stage process was used. At first, an NBR/PVC blend was mixed with a mono-tetra-n-butylammonium salt of triazine trithiol at a temperature of 100°C on a two-roll mill to give the branching structure of triazine thiols into PVC. In the second stage branched NBR/PVC reacted with DTDM to afford the branched PVC containing trithiomorphonyl groups. In the presence of ZnO at 160°C trithiomorphonyl groups react with NBR to form a crosslinking structure between NBR and PVC. The mechanical properties of cured NBR/PVC blends were markedly improved by the treatment process and after addition of tetramethylthiuram monosulphide also. The mechanical properties were not improved by increasing the concentration of TT-TBA (tetrabutylammonium salt of 1,3,5-triazine-2,4,6-trithiol) over 4.2 phr. 相似文献
102.
Yoshiyuki Abe Fabrizio Tappero Yuki Tanaka Yoshiki Takagi Giovanni Maizza 《Microgravity science and technology》2006,18(3-4):178-183
The effect of gravity on materials processing is rather complicated, and a large number of considerably unexpected results due to high gravity or sometimes centrifugation have been reported. The authors have been conducting high gravity diamond thin film growth by the DC-plasma CVD method up to 100 G. The effects of high gravity appeared in the nucleation site density, growth rate, grain size, uniformity, film coverage and morphology. With the increase in gravity, the nucleation site density, growth rate, grain size were all found to be increased, the uniformity and film coverage were improved, and {100} facet became dominant rather than {111} facet. To understand the deposition mechanism in these effects observed in high gravity, a diagnostic apparatus for spectroscopic study of the optical emission from the DC-plasma was developed, and the OES (optical emission spectroscopy) apparatus has been employed in high gravity CVD experiments. The influence of gravity on the most active species in the plasma, such as H, CH, C2 was discussed together with the results from the Raman spectroscopy and X-ray diffraction study. 相似文献
103.
A new empirical large-signal HEMT model 总被引:1,自引:0,他引:1
Shirakawa K. Shimizu M. Kawasaki Y. Ohashi Y. Okubo N. 《Microwave Theory and Techniques》1996,44(4):622-624
We propose an empirical large-signal model of high electron mobility transistors (HEMTs). The bias-dependent data of small-signal equivalent circuit elements are obtained from S-parameters measured at various bias settings. And Cgs, Cgd, gm, and gds, are described as functions of Vgs and Vds. We included our large-signal model in a commercially available circuit simulator as a user-defined model and designed a 30/60-GHz frequency doubler. The fabricated doubler's characteristics agreed well with the design calculations 相似文献
104.
105.
Shirakawa S. Owada S. Iimura N. Kurita K. Yamazaki T. Shindo K. Yamauchi Y. 《Power Delivery, IEEE Transactions on》1988,3(1):183-186
A super-compact SF6 gas insulated neutral grounding resistor (NGR) is presented that uses recently developed high-power resistors made of a novel ceramic material. The microstructure, voltage-current characteristics, and current-carrying characteristics of the resistor element are examined. The composition and features of the NGR are discussed 相似文献
106.
E.s.r. spectra of peroxy radicals trapped in isotactic and atactic polypropylenes have been observed at various temperatures. The spectrum observed at 77 K was shown to be composed of one component by comparing it with that at 4 K. The spectra observed at higher temperatures comprised of two spectra arising from the rigid peroxy radicals and the mobile peroxy radicals. All of the observed spectra have been reconstructed by means of computer simulation and the changes in anisotropic g-values with temperature were estimated. The motion of the mobile fraction was shown to be rotation or rotatory vibration of the radicals around the chain axis both in the isotactic polypropylene and in the atactic polypropylene as well as in polyethylene and poly(tetrafluoroethylene) although the structures of the polymers are different, that is helical (polypropylene) or planar zigzag (polyethylene, poly(tetrafluoroethylene)). 相似文献
107.
K Tobinai T Hotta H Saito K Ohnishi R Ohno M Ogura Y Ariyoshi K Takeyama T Kobayashi Y Ohashi S Shirakawa 《Canadian Metallurgical Quarterly》1996,26(6):455-460
Irinotecan hydrochloride (CPT-11) is a new derivative of camptothecin which inhibits topoisomerase I. Phase II studies have demonstrated that CPT-11 is active against a broad spectrum of neoplasms including intractable non-Hodgkin's lymphoma. An early phase II study in lymphoma suggested that a schedule of daily infusions of 40 mg/m2/day for three or five consecutive days is more effective than a single infusion of 200 mg/m2 every three to four weeks. Carboplatin is also an active agent against lymphoma, and preclinical studies have shown that CPT-11 and its active metabolite have a synergistic effect with platinum compounds. To evaluate the maximal tolerated dose (MTD) and the therapeutic efficacy of CPT-11 in combination with carboplatin in relapsed or refractory non-Hodgkin's lymphoma, we conducted a combination phase I/II study. The starting dose of CPT-11 was 20 mg/m2/day (days 1 through 3 and 8 through 10), and dose escalations of 5 mg/m2/day increments were planned, with a fixed dose of carboplatin (300 mg/m2, day 1). Six of the eight patients receiving both agents at the starting dose level developed critical toxicities such as grade 4 hematologic (neutropenia 6/8, thrombocytopenia 1/8) and grade 3 non-hematologic toxicities (diarrhea 2/8, transaminase elevation 1/8). Further dose escalation of CPT-11 was halted, and the starting doses were judged to be the MTDs. The response rate (25%, 2/8) to the combination of the MTDs was not superior to that of CPT-11 alone in a previous phase II study (38%, 26/69), and the MTD of CPT-11 in combination with carboplatin was less than half the single-agent dose. We conclude that carboplatin is not recommendable for combination with CPT-11 in lymphoma patients. Other suitable agents for such a combination should be sought. 相似文献
108.
109.
110.
Guanshi Qin Shenghong Huang Yan Feng A. Shirakawa K.-I. Ueda 《Photonics Technology Letters, IEEE》2005,17(9):1818-1820
In this letter, we report on a multiple-wavelength up-conversion laser in Tm/sup 3+/-doped ZrF/sub 4/--BaF/sub 2/--LaF/sub 3/--AlF/sub 3/--NaF glass fiber pumped by an 1120-nm fiber laser. Single-wavelength, two-wavelength, and three-wavelength up-conversion lasers can be obtained by adjusting the distance between the coupler mirror and the fiber end, which is attributed to the frequency-filter effect in the etalon composed of the coupler mirror and the fiber end. The effects of the pump power on the performance of dual-wavelength laser were also discussed. 相似文献