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141.
The viscosity lowering of toluene solutions of isobutylene-isoprene rubber, polyisobutylene, and ethylene-propylene rubber in the reaction with dicumyl peroxide was investigated. By using the kinetic equations for the reaction of rubber with peroxide which had been derived previously by KIRIYAMA et al. the results of the experiments are discussed. 相似文献
142.
A new idea for the development of ultra high strength steels by utilizing the spinodal decomposition of the Fe-Mo binary system is proposed. The idea comprises the restraint of the brittleness of the Fe-Mo alloy by reducing the Mo-content necessary to spinodal decomposition and by microstructure refining such as grain refining, subgrain refining etc; the former is realized by the alloying with some elements which, in general, have a tendency towards ordering (i.e., negative interchange energy between the nearest neighbour atoms) when combined with iron, and the latter by thermomechanical treatment and/or cold rolling. On the basis of the idea, that hidden properties indispensable to high strength materials are successfully drawn from the Fe-Mo alloy; we have obtained a 4GPa grade high tensile steel of Fe-Mo-Co-V. This idea is sure to contribute new suggestions to the development of high strength materials. 相似文献
143.
通过辐射聚合,在纸表面覆盖阳离子——疏水性共聚物polo(DEAEMA-ATMPT)和阴离子——疏水性共聚物poly(AA-ATMPT)作为固定化绿色木霉细胞的载体。试验结果表明:用覆盖poly(DEAEMA-ATMPT)的载体固定化细胞比较牢固,未因振荡而解吸;固定化细胞的FPA(滤纸活性)均高于未固定化的游离细胞,其中用覆盖25%:75% poly(DEAEMA-ATMPT)的载体固定化细胞的FPA比游离细胞增加了20%;固定化细胞的重量随共聚物中阳离子组分的增加而增加。用覆盖poly(AA-ATMPT)的载体固定化绿色木霉也有较好的效果。但固定化细胞的重量明显低于覆盖poly(DEAEMA-ATMPT)的载体固定化细胞的重量,且它随共聚物中阴离子组分的增加而下降。阳离子——疏水性共聚物能提高固定化绿色水霉的效果;用离子型共聚材料固定化细胞静电引力起了主要的作用。 相似文献
144.
145.
Carbonaceous spherules of mesophase were examined by transmission electron microscopy (TEM) and X-ray diffraction to precisely
clarify its structure. A series of thin sections were cut from a single spherule with a microtome, and the three-dimensional
lamellar structure of the spherule investigated. From 002 dark-field images and selected area electron diffractions (SAD),
it was observed that the spherule was of the Brooks-Taylor type, with the lamellae being parallel even at the poles of the
spherule. Structural changes within the spherule was studied following carbonization and graphitization. The structure of
the resultant coke was essentially that of spherule of mesophase. Size of the lamellae increased as well as. The number of
stacking lamellae also increased, but a rapid increase was not seen. The spherules of mesophase show a high degree of homogeneity
and an excellent degree of graphitization. 相似文献
146.
日本建筑材料协会 日本建筑材料协会是通过国土交通省、经济产业省认可的具有全国性规模的公益法人.主要以建筑材料生产厂家、销售公司、施工公司等与建材相关的企业为主体.在日本国内会员数已超过300家公司。协会于1934年成立.约有70年的历史。现在,正致力于新时代建材的开发、启蒙与普及以及会员企业和建筑业的进步、发展贡献着力量.同时还积极参与公益活动。 相似文献
147.
Toshimi Yamane Masatoshi Yasunaga Keiichi Hirao Shinsuke Yamasaki Keizo Kazama Kosei Yoshida Rikio Takeda Minoru Hiratani 《Journal of Materials Science》1988,23(1):305-310
Repetition numbers of bending of Cu-0.81 wt% Cr, Cu-0.81 wt% Cr-0.14 wt% Sn and Cu-0.26 wt% Cr-0.10 wt% Sn alloys were investigated. After solution treatment, the first two types of copper alloys have a primary chromium phase; this is not so in the last alloy. The primary chromium phase does not influence the repetition numbers of bending of cold-rolled specimens; the repetition numbers of bending of specimens aged at 723 K for 1.8 × 103 sec after cold rolling are higher than those of cold-rolled specimens. The cause of this is considered to be a recovery of work-hardening during ageing. 相似文献
148.
149.
150.
The effect of polyethyleneglycol on the radical polymerization of methyl methacrylate initiated with an aqueous solution of sodium polystyrenesulfonate was studied. Under the definite condition, the conversion of methyl methacrylate raised from 6.6 to 100% by the addition of polyethyleneglycol. It was concluded that polyethyleneglycol acted only as a host of Na+, but not as a phase transfer catalyst. 相似文献