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31.
In this paper are described the main characteristics of the plasma spraying process of alumina deposits, i.e., the temperature and flow field of the plasma jets obtained with the classical spraying torches, the injection of the particles into the plasma jet, the particle surface temperature and velocities in the plasma (measured for calibrated alumina particles), and the coating generation. The measurements on the alumina particles are compared with the predictions of a mathematical model. The experimental and computed particle velocities are in rather good agreement. However, this is not the case for the particle surface temperature. Possible reasons for the discrepancy are proposed (influence of the carrier gas, thermophoretic forces, and poor penetration of the particles into the plasma core even for an injection velocity twice that of the optimal calculated one, as shown by recent measurements). Finally the correlations between the particle velocities and surface temperature, and the properties of the alumina coating (porosity, crystal structure, mechanical properties) are studied. 相似文献
32.
酞菁氧钛/卟啉氧钒复合体系光导性能的协同增强效应 总被引:9,自引:0,他引:9
在酞菁氧钛(TiOPc)/卟啉氧钒(VOTPP)复合光生材料中发现了光敏性的非线性增强现象,对复合体系的电子跃迁光谱和X射线衍射图的研究结果表明,在基态下两种材料之间没有明显相互作用,光致放电研究说明,该现象来自光激发状态下复合体系中的隙间态跃迁对光导的贡献,XPS测试结果表明酞菁氧钛与卟啉氧钒分子之间存在着定向的部分电荷转移,光致激发状态下的电荷转移是协同增强效应的起因,这种协同增强效应为利用弱的电子给体与弱的受体复合体系设计新型光导材料与器件提供了新方法。 相似文献
33.
Pengchong Li Zhi Shang Kejian Cui Huan Zhang Zhi Qiao Caizhen Zhu Ning Zhao Jian Xu 《中国化学快报》2019,30(1):157-159
Polystyrene (PS) fibers with core-shell structure were prepared by coaxial electrostatic spinning using liquid epoxy or curing agent as the core and PS solution as the shell. Scratch self-healing coatings were realized by using the healant-loaded core-shell fibers in the matrix. 相似文献
34.
J. A. Hageman R. Wehrens H. A. van Sprang L. M. C. Buydens 《Analytica chimica acta》2003,490(1-2):211-222
Constructing multilayer optical coatings (MOCs) is a difficult large-scale optimisation problem due to the enormous size of the search space. In the present paper, a new approach for designing MOCs is presented using genetic algorithms (GAs) and tabu search (TS). In this approach, it is not necessary to specify how many layers will be present in a design, only a maximum needs to be defined. As it is generally recognised that the existence of specific repeating blocks is beneficial for a design, a specific GA representation of a design is used which promotes the occurrence of repeating blocks. Solutions found by GAs are improved by a new refinement method, based on TS, a global optimisation method which is loosely based on artificial intelligence. The improvements are demonstrated by creating a visible transmitting/infrared reflecting filter with a wide variety of materials. 相似文献
35.
36.
采用溶胶-凝胶法制备无孔脲醛树脂-二氧化锆复合微球,在碳酸盐缓冲溶液中,利用微球表面的酰胺键与三嗪染料-活性艳蓝X-BR分子中三嗪环上的活泼氯反应,将染料键合到微球表面,以牛血清白蛋白(BSA)为样品,考察了不同条件下,该萃取剂对BSA的萃取能力。结果表明,该萃取剂对BSA的饱和萃取量达到30.3 mg.g-1,同时萃取的蛋白易于洗脱,1.0 mol.L-1氰化钾的洗脱率达到93.5%。 相似文献
37.
The manufacturing of ophthalmic lenses is one of the most important markets worldwide and, therefore, strong research efforts are undertaken to continuously improve the quality of the products, either silicate glasses or organic polymer lenses. Hybrid sol-gel based materials play a major role in this highly competitive field and have contributed significantly to the commercial success of the organic base materials. Recent developments concern fast curing and patternable coatings that might soon become part of this business. The compatibility of hybrid sol-gel materials either with organic dyes or with inorganic vacuum borne coatings offers further possibilities to develop highly sophisticated lenses meeting not only customer needs like perfect corrective function, high optical quality and protection, but also high durability as well as cosmetic and decorative aspects. An overview and a few recent developments are outlined below. 相似文献
38.
肝素化壳聚糖季铵盐/壳聚糖复合膜抗凝血性能的研究 总被引:13,自引:1,他引:13
以壳聚糖季铵盐,壳聚糖为基本原材料,选用戊二醛为交剂剂及固定剂,制备一种物理机械性能较优的抗凝血材料。探讨了戊二醛及肝素钠两者用量对肝素化程度及血液生的影响。 相似文献
39.
Structural investigations of thin films of SiC, SiC with free silicon and various titanium suicides (TiSi2, TiSi and Ti5Si3) are described. The crystal phases have been identified using X-ray diffractometry. The growth of reaction products from surface reactions between silicon and deposited titanium can be observed.Dedicated to Professor Dr. rer.nat. Dr. h.c. Hubertus Nickel on the occasion of his 65th birthday 相似文献
40.
To obtain new materials with synergetic or complementary behaviors, polyaniline composite filled with ZnO rods in ramification-like
structure was prepared by a hydrothermal approach. Comparative experiments of ZnO preparation in the presence of some metal
ions were also carried out. The results indicated that the morphology of ZnO was strongly affected by the preparation condition.
The method to grow ZnO rods in the presence of polyaniline offers a simple approach to obtain polyaniline composite filled
with linear ZnO structure. The results of X-ray photoelectron spectroscopy show that the strong interaction between ZnO and
polyaniline possibly exists to cause the charge transfer. 相似文献