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51.
对不饱和聚酯树脂 (UPR)废料裂解制原料油技术进行了研究 ,系统地考察了催化裂解反应工艺条件。试验结果表明 ,催化裂解所需反应温度为 40 0~ 45 0℃ ,反应时间为 70~ 80min ;剂油比 1∶5 ;试验对 4种催化剂的催化性能进行了评价 ,研究表明单独使用YB -2催化剂 ,液相产品收率为 5 8.2 2%~ 5 9.1 4% ;YB -1和YB -2混合使用 ,最高液相产品收率为 68.76%。 相似文献
52.
Copolythiophenes (Co‐PTs), poly(3‐hexylthiophene‐co‐3‐thiophene carboxylic acid) (P3HT‐TCa), poly(3‐hexyloxylthiophene‐co‐3‐thiophene carboxylic acid) (P3HOT‐TCa), and poly(3‐phenylthiophene‐co‐3‐thiophene carboxylic acid) (P3PhT‐TCa), were synthesized by chemical oxidized polymerization to investigate the effect of copolymerization on the properties of polythiophenes (PTs). Gel permeation chromatography showed that the molecular weight (MW) of Co‐PT was lower than that of homopolythiophene. Fourier transform infrared (FTIR) spectra indicated that the copolymerization was successful between the monomers. The λmax of Co‐PTs gave a “blue shift” in ultraviolet‐visible (UV‐VIS) spectra. Photoluminescence (PL) spectra showed that the PL intensity of Co‐PT became weaker than that of homopolythiophene and the disappearance of PL had been observed in P3HOT‐TCa. The thermal stability of Co‐PT was influenced by the carboxyl for its low decomposition temperature. Furthermore, the copolymerization between multi‐wall carbon nanotube containing thiophene ring (MWNT‐Th) and 3‐hexyloxylthiphene could also take place successfully. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
53.
54.
矾土尖晶石钢包浇注料的研制与应用 总被引:2,自引:0,他引:2
采用特级矾土熟料为骨科,天然出合成的镁铝尖晶石为部分基质,选用新型复合结合剂研制成矾土尖晶石质钢包浇注料.使用结果表明:一次性寿命较传统的铝镁浇注料提高80%以上. 相似文献
55.
Fu-Ping Zhang Jin-Mei Du Yu-Sheng Liu Hong-Liang He 《Journal of the American Ceramic Society》2007,90(8):2639-2641
Shock-induced depoling of the ferroelectric (FE) ceramic PZT 95/5 is utilized in a number of pulsed power devices. Nondestructive testing of remanent polarization of PZT 95/5 is developed by pyroelectric effect in this paper. Approximately linear relation between the change of polarization during low- to high-temperature rhombohedral FE phase and the remanent polarization was found through pyroelectricity of a single piece of PZT 95/5 ceramics. The change of polarization of a prototype for shock-driven pulsed power during the FEHT ↔FELT phase transformation was also investigated through directly measuring the pyroelectric current. Results indicate that pyroelectric effect caused by the reversible FEHT –FELT phase transition could be used as a non-destructive inspection for the remanent polarization of a prototype about shock-driven pulsed power supply. 相似文献
56.
杜美丹 《数字社区&智能家居》2014,(25):6015-6018
在环境保护和节约能源要求下,发展电动汽车已经成为重要的产业方向,但现有电动汽车发展还不够成熟,存在续航里程不足的缺点,充换电服务网络也还不够普及,因此对汽车行驶线路耗电量少的路径搜索就尤为重要。基于Dijkstra算法和Floyd算法提出了一种查找电动汽车在不同道路工况下行驶时耗电量最少的路径模型,得到了电动汽车行驶的最优路径,模型并使用Matlab软件自带语言编程并仿真,得到直观的路线信息、距离。 相似文献
57.
Co–BaCO3 catalysts exhibited high catalytic performance for oxidative dehydrogenation of ethane (ODE) using CO2 as oxidant. The maximal formation rate of C2H4 was 0.264 mmol · min−1 · (g · cat.)−1 (48.0% C2H6 conversion, 92.2% C2H4 selectivity, 44.3% C2H4 yield) on 7 wt% Co–BaCO3 catalyst at 650 °C and 6000 ml. (g · cat.)−1. h−1. Co–BaCO3 catalysts were comparatively characterized by XRF, N2 isotherm adsorption-desorption, XRD, H2-TPR and LRs. It was found that Co4+–O species were active sites on these catalysts in ODE with CO2. The redox cycle of Co–O species played an important role on the catalytic performance of Co–BaCO3 catalysts. On the other hand, the co-operation of BaCO3 and BaCoO3 was considered to be one of possible reasons for the high catalytic activity of these catalysts. 相似文献
58.
Douglas-G.Ivey 《北京科技大学学报(英文版)》2010,17(4):459-463
Ni/Sn couples,prepared by sequentially electroplating Ni layers and Sn layers on metallized Si wafers,were employed to study the mierostructures and growth kinetics of Ni-Sn intermediate phases,when the Ni/Sn couples were aged at room temperature or annealed at temperatures from 150 to 225℃for various times.The results show that the NiSn phase and Ni_3Sn_4 phase are formed,respectively,in the aged couples and annealed couples.The Ni_3Sn_4 layer is continuously distributed between the Ni and Sn sides in t... 相似文献
59.
目的:阐述实验动物在血液制品生产质量控制过程中应用的重要性。方法:按《中华人民共和国药典》2005年版三部要求及相关项目的技术规范进行血液制品质量控制。结果:血浆数量150吨,可同时生产以下品种的产品,人血白蛋白共30批次,总瓶数约40万瓶(折10g);免疫球蛋白类:共30批次,总瓶数约30万瓶(折2.5g);人纤维蛋白原:共30批次,总瓶数约15万瓶(折0.5g);人凝血酶原复合物:共30批次,总瓶数约12万瓶(折300IU);人凝血因子Ⅷ:共30批次,总瓶数约10万瓶(折200IU)。需使用家兔870只、豚鼠300只小鼠750只。结论:实验动物应用于血液制品生产质量控制发挥了非常重要的作用。 相似文献
60.
Ca
x
Ba1−x
TiO3 (CBT) fine particles doped with red luminescence center of Pr3+ ions (Pr: CBT) were successfully synthesized by salt assisted spray pyrolysis (SASP) process. Scanning electronic microscope
(SEM) and laser scattering analysis demonstrate that salt can be removed from the surface of particles by washing with Milli-Q
water and the particles can be further separated by ball-milling to get well-dispersed Pr3+ ions doped CBT fine particles. The luminescence properties, such as photoluminescence (PL) and mechanoluminescence (ML),
of as-synthesized Pr: CBT particles were investigated. For Pr: CBT fine particles with different Ca molar ratios, all the
samples show one emission at 612 nm, with increasing Ca molar ratio, PL intensity of Pr: CBT fine particles become stronger
and stronger. When pressure was loaded on the Pr: CBT pellet, mechanoluminescence(ML) emission was measured. The results show
that the ML intensity is proportional to the applied pressure. 相似文献