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81.
82.
WANG Mingxu H. Miyauchi T. Nakahata Y. Nishikawa Y. Oya N. Noda K. Okuno 《核工业西南物理研究院年报(英文版)》2004,(1):50-51
Boron is an attractive candidate of the first wall coating materials in fusion reactors. The behavior of deuterium implanted into boron films has been studied . This paper reports the effect of thin oxygen-containing boron layer on the behavior of deuterium im- planted into boron film by X-ray photoelectron spectroscopy (XPS) and thermal desorption spectroscopy (TDS). 相似文献
83.
Chemical and Physical Analysis of Acetate-Oxide Sol-Gel Processing Routes for the Y-Ba-Cu-O System 总被引:2,自引:0,他引:2
Tarek?MouganieEmail author Michelle?A.?Moram Joy?Sumner Bartek?A.?Glowacki Bart?Schoofs Isabel?Van?Driessche Serge?Hoste 《Journal of Sol-Gel Science and Technology》2005,36(1):87-94
The formation of three sols by fluorine-free aqueous and non-aqueous processes were analyzed and modified to vary the chemical properties of the sols (inks) to suit a variety of deposition processes such as dip-coating and ink-jet coating/printing. Ink-jet printing requires high wetting angles; choosing the right complexing agents to modify the ink allows the formation of droplets with high wetting angles on the surface. Dip-coating and ink-jet coating require low wetting angles; additives added to the sols reduce wetting angles to 10∘ and allow complete coverage of the substrate surface. The deposition theories and requirements are briefly discussed, as are some initial tests with the printing and converting of the developed superconducting inks. 相似文献
84.
空心微珠表面化学镀Ni-Co-P合金 总被引:13,自引:0,他引:13
以无机非金属粉煤灰空心微珠为芯材, 利用化学镀工艺对其表面进行金属化改性, 可以得到表面完整包覆的导电粉体, 该粉体具有中空, 质轻, 粒度细, 高强度, 耐高温, 导电性能好等多种优异性能, 可部分代替金属和铁氧体微粉作为电磁波吸收剂. 采用SnCl2和PdCl2进行敏化-活化处理后, 在空心微珠表面化学包覆Ni-Co-P合金层, 利用XRD、EDS、SEM和镶嵌金相等方法对样品进行形貌观察和分析表征, 结果表明, 使用PdCl2作活化剂可以得到优质均匀的Ni-Co-P合金镀层, 镀层光亮, 均匀, 包覆完整. 化学镀后镀层呈非晶态, 450 ℃氢气气氛下热处理后出现结晶相Ni3P和六方晶系的α-Co单质. 相似文献
85.
A simple and robust static adsorptive (dynamic) coating process using 2% hydroxyethylcellulose was developed for surface modification of poly(methyl methacrylate) (PMMA) microfluidic chips for DNA separations, suitable for usage over extended periods, involving hundreds of runs. The coating medium was also used as a sieving matrix for the DNA separations following the coating process. Four consecutive static treatments, by simply filling the PMMA chip channels with sieving matrix once every day, were required for obtaining a stable coating and optimum performance. The performance of the coated chips at different phases of the coating process was studied by consecutive gel electrophoretic separations with LIF detection using a PhiX-174/HaeIII DNA digest sample. The coated chip, with daily renewal of the sieving matrix, showed high stability in performance during a 25-day period of systematic study, involving more than 100 individual runs. The performance of the coated chip also remained almost the same after 3 months of continuous usage, during which over 200 separations were performed. The average precision of migration time for the 603-bp fragment was 1.31% RSD (n = 6) during the 25-day study, with a separation efficiency of 6.5 x 10(4) plates (effective separation length 5.4 cm). 相似文献
86.
In this paper, we describe a method for size-based electrophoretic separation of sodium dodecyl sulfate (SDS)-protein complexes on a polymethyl methacrylate (PMMA) microchip, using a separation buffer solution containing SDS and linear polyacrylamide as a sieving matrix. We developed optimum conditions under which protein separations can be performed, using polyethylene glycol (PEG)-coated polymer microchips and electrokinetic sample injection. We studied the performance of protein separations on the PEG-coated PMMA microchip. The electrophoretic separation of proteins (21.5-116.0 kDa) was completed with separation lengths of 3 mm, achieved within 8 s on the PEG-coated microchip. This high-speed method may be applied to protein separations over a large range of molecular weight, making the PEG-coated microchip approach applicable to high-speed proteome analysis systems. 相似文献
87.
H. Y. Yue W. D. Fei Z. J. Li L. D. Wang 《Journal of Sol-Gel Science and Technology》2007,44(3):259-262
Zinc nitrate and citric acid were used to prepare ZnO sol. ZnO and ZnAl2O4 coated aluminum borate whiskers were separately prepared by a sol–gel process. The results show that ZnO forms when ZnO xerogel
is calcined at 500 °C and it does not undergo any phase transformation in the range of 500 and 1000 °C during calcinations.
In ZnO xerogel coated aluminum borate whiskers system, a large amount of heat, gas and pores are produced during the heating
process. When ZnO xerogel coated aluminum borate whiskers are calcined at 500 °C, ZnO can be uniformly coated on the surface
of the whikers and the coated whiskers can be easily dispersed in distilled water through an ultrasonic vibration apparatus.
During the calcination of ZnO coated whiskers at 1000 °C, ZnO reacts with the whiskers and ZnAl2O4 forms on the surface of aluminum borate whiskers. 相似文献
88.
Ultrathin phenyl-functionalized solid phase microextraction fiber coating developed by sol-gel deposition 总被引:1,自引:0,他引:1
A new sol-gel application for the development of SPME fibers is described. Phenyltrimethoxysilane (PTMOS) and methyltrimethoxysilane (MTMOS) were the sol-gel precursors used at different proportions, together with different water contents, catalyst and reaction time. It was observed that obtaining a good film quality was determinant for a good extracting fiber performance. The film thickness ranged 0.2-1 microm and could not be increased by multi-coating processes. Apparently, a dense, non-porous microstructure was obtained. These coatings exhibited a strong hydrophobic character, as shown by the capability of extraction of long chain and apolar aromatic compounds, which, was comparable to that of the 100 microm polydimethylsiloxane (PDMS) and 65 microm carbowax-divinylbenzene (CW-DVB). The developed fiber has shown high thermal (350 degrees C) and organic solvent stability (ethanol, toluene and dichloromethane), thus bearing adequate characteristics to be associated to GC and potentialities that may also envisage suitability for HPLC. The new fibers may be useful for the microextraction of non-polar compounds, although at trace levels and in simple matrixes only, due to the susceptibility to competition. 相似文献
89.
To improve corrosion protections, a better understanding of the coating behavior and therefore the interaction properties between the inhibitor and the surface is a vital factor. Density functional theory (DFT) simulations were used to explore the adsorption properties of the pure epoxy and nano-SiO2-epoxy composites on the Al2Cu surface. The interaction energies and transferred charges of adsorbed composites on the Al2Cu surface and their optimized structures with various interacting orientations are investigated. It is found that nano-SiO2-epoxy adsorb more strongly on Al2Cu substrate in comparison with the epoxy matrix with interaction energies of ˗228.084 kcal/mol and ˗35.341 kcal/mol, respectively. The validity of our computational methods was evaluated by experiments as well as high-level quantum chemistry method. The atom-in-molecules analysis with DFT indicates that the interaction nature is typical for electrostatics. The stability of the adsorption behavior of composites on the surface was also explored by DFT-based molecular dynamics simulation. 相似文献
90.