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81.
Koshiro Hashimoto Takao Fujisawa Masahiro Kobayashi Ryutoku Yosomiya 《应用聚合物科学杂志》1982,27(12):4529-4539
Modified glass fibers, containing unsaturated hydrocarbon surface groups, were prepared by a hydrothermal treatment, with allylglycidylether in excess as reagent. Graft polymerization of the treated glass fiber with styrene and methylmethacrylate was carried out in sealed tubes, under nitrogen, using benzoyl peroxide (BPO) and cumene hydroperoxide (CHPO) as initiators. When BPO was used as the initiator, the grafting efficiency was extremely low, but the graft copolymerization behavior was similar to that of usual organic polymers. With CHPO, both grafting ratio and grafting efficiency were very high. Various properties of composite materials containing grafted glass cloth were studied. Flexural strength, flexural modulus, and interlaminar shear strength increased proportionally to the increase of the grafting ratio; the same values were decreased only in a small extent after the boiling test. 相似文献
82.
I Hashimoto UW Schnyder I Anton-Lamprecht T Gedde-Dahl S Ward 《Canadian Metallurgical Quarterly》1976,256(2):137-150
In this paper the authors describe and analyse results that they obtained by infection of the guinea pig organism carried out by subcutaneous or intratracheal application with five mycobacterial strains, namely Myco bovis BCG-Praha, Myco the H37Ra, Myco Kansasii, Myco fortuitum and Myco smegmatis. At predetermined time intervals following subcutaneously or intratracheally performed infection (on 7th, 16th, 28th and 56th day after infection) transplantation of a Deals' guinea pig sarcoma cell suspension was carried out in guinea pigs by the intraltracheal route. As it appears from the results gained the applied mycobacteria exhibit a partial inhibition of growth od Deals' guinea pig sarcoma cells of different character. From among the utilized strains the Myco bovis BCP-Praha and the Myco tbc H37Ra exhibited the highest, Myco fortuitum and Myco smegmatis the lowest inhibitory activity. Intratracheally performed infections yielded in general better results on the growth inhibition than infections carried out with the same strain but by the subcutaneous route. Furthermore, in the experiments reported on in the present paper the authors could verify their earlier experience, namely that inhibition of growth of sarcoma cells is most pronounced at the time of maximal biological activity (logarithmic phase of multiplication) of the applied mycobacterium. 相似文献
83.
S Kurooka M Hashimoto M Tomita A Maki Y Yoshimura 《Canadian Metallurgical Quarterly》1976,79(3):533-541
About 100 S-fatty acyl thiol compounds designed as substrates for pancreatic lipase [EC 3.1.1.3] were synthesized and tested for susceptibility to hydrolysis by hog pancreatic lipase and hog hepatic carboxylic esterase [EC 3.1.1.1] using 5,5'-dithiobis(2-nitrobenzoic acid) as a chromogenic reagent to determine the hydrolytic rates of their S-acyl bonds. In general, the hydrolytic rates of S-acyl bonds by the lipase were fast with thioglycerol type thiol moieties, slow with dithioethyleneglycol type or monothiol type, and negligible with thiopolyol type. As for the acyl moieties, the hydrolysis of the S-acyl bonds was fast with C3-5 acyl groups, followed by C6-8 acyl groups, and the rate decreased as the acyl chain length deviated from these values or branched. On the other hand, the hydrolysis of S-acyl bonds by the esterase occurred with all types of S-acyl esters except for esters of long S-acyl chains. Of all the compounds tested with the lipase, the rate of hydrolysis of S-acyl bond was maximum with 2,3-dimercaptopropan-1-ol tributyroate [I], high with 3-mercaptopropane-1,2-diol tributyroate [II], but negligible with the analogous compound, 1,3-dimercaptopropan-2-ol tributyroate. Compounds [I] and [II] may be practically useful as substrates for lipase assay in human serum samples pretreated with phenylmethylsulfonyl fluoride, a potent inhibitor against both serum arylesterase [EC 3.1.1.2] and hepatic esterase, which attack [I] and [II]. 相似文献
84.
Takeshita K. Takeshita S. Hashimoto H. 《Electromagnetic Compatibility, IEEE Transactions on》1979,(1):33-40
The paper analyzes the scattering characteristics of VHF/UHF television broadcasting waves which are obliquely incident on finite length multibundle conductors of overhead power transmission lines. Numerical calculations were made for four-bundle conductors currently employed in Japan; the attenuation, directivity, and frequency characteristics were clarified. To verify the theoretical results, 1:40 scale (for VHF) and 1:10 scale for (UHF) model experiments have been carried out. Agreement between the theoretical results and the measurements was reasonably good. 相似文献
85.
Polymer film-type channel electron multipliers (CEMs) were developed and their characteristics investigated in comparison with bulk-type flexible CEM. As film-type CEMs, a paint-coating-type CEM and a solvent-etching-type CEM were fabricated. The paint-coating-type CEM is made by coating a “paint” which is prepared by dissolving in a solvent an electronically conductive polymeric composition having a high secondary electron emission yield. Up to the present study the mean gain of the film-type CEM, in spite of the lower resistivity of the dynode, seems to be slightly more dependent on the count rate than that of the bulk-type CEM made of the same material. However, the convenience of fabricating the dynode film by coating the dynode-forming paint on the internal surface of any shaped tube or a flexible polymer tube would overcome the slight disadvantage mentioned above. 相似文献
86.
87.
Akahane K Hashimoto M Hada M Takano Y Ono K Kai M Kusama T 《Radiation protection dosimetry》2003,103(1):41-45
As the survival rate of newborns has increased, the number of X ray computed tomography (CT) examinations performed on neonates has been increasing. The exposure doses from CT examinations are known to be higher than those from conventional radiography. Although radiation sensitivity of neonates is higher than that of adults, there are few reports on dose estimates of neonates in CT examinations. Four cylindrical phantoms and one neonatal phantom have been developed to estimate doses to neonates during CT examinations. Using these phantoms and glass dosemeters, absorbed doses were measured. Estimated exposure doses to neonates were higher than those to adults, and our results suggest a need to optimise carefully CT examinations in newborns. 相似文献
88.
Songlan?Yang Zheng-Ming?SunEmail author Hitoshi?Hashimoto 《Materials Research Innovations》2003,7(4):225-230
Ti/Si/TiC powder mixture with molar ratios of 2:2:3 were sintered at various temperatures from 700–1300 °C for 15 min by PDS technique. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used for the evaluation of phase composition in different samples for the understanding of the sintering mechanism for this system. Results showed that Ti5Si3 formed as the intermediate phase during sintering. The reaction between Ti5Si3 and TiC as well as Si induces the formation of Ti3SiC2, and TiSi2 appears as the byproduct in this process. At temperature above 1000 °C, TiSi2 reacts with TiC to form Ti3SiC2. High Ti3SiC2 phase content bulk material can be synthesized at 1300 °C for 15 min. 相似文献
89.
N. Hashimoto A. Handa M. Nakagawa K. Obara H. Yano O. Ishikawa T. Hata 《Journal of Low Temperature Physics》2007,148(3-4):299-303
We have investigated the turbulence transition of the superfluid 4He flow generated by a vibrating wire. For a 1.2-kHz vibrating wire, we observed intermittent switchings between laminar and
turbulent flows. The switching rate decreases with increasing temperature above 100 mK, until no occurrence of the switchings
at 350 mK. For a 2.4-kHz vibrating wire, we find that the switching rate is much lower than that of the 1.2-kHz vibrating
wire even at low temperatures. This result indicates that a mechanism causing the switchings is influenced by the temperature
and the oscillation frequency of the superfluid flow. 相似文献
90.
Thermal Degradation Under Pulse Operation in Low-Temperature p-Channel Poly-Si Thin-Film Transistors
Shinichiro Hashimoto Koji Kitajima Yukiharu Uraoka Takashi Fuyuki Yukihiro Morita 《Electron Devices, IEEE Transactions on》2007,54(2):297-300
We analyzed the heat generation of a low-temperature polycrystalline thin-film transistor in pulse operation and proposed a technique for accurately measuring its thermal temperature in high-frequency operation. From this measurement, we were able to calculate the time constants for heating and radiation for the first time. At a low frequency, the temperature difference between when the pulse was on and off was remarkable. As the frequency was increased, the maximum and minimum temperatures approached each other and became equal at a frequency of approximately 1 kHz. We also measured the degradation in pulse operation and discussed the relationship between the thermal temperature and the degradation in the pulse operation 相似文献