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Two groups of coated conductor samples with different thicknesses of CeO2 cap layers deposited by pulsed laser deposition (PLD) under the same conditions have been studied. Of them, one group is of CeO2 films, which are deposited on stainless steel (SS) tapes coated by IBAD-YSZ (IBAD-YSZ/SS), and the other group is of CeO2/YSZ/Y2O3 multilayers, which are deposited on NiW substrates by PLD for the fabrication of YBCO-coated conductor through the RABiTS approach. YBCO film is then deposited on the tops of both types of buffer layers by PLD. The effects of the thickness of the CeO2 film on the texture of the CeO2 film and the critical current density (Jc) of the YBCO film are analysed. For the case of CeO2 film on IBAD-YSZ/SS, there appears a self-epitaxy effect with increasing thickness of the CeO2 film. For CeO2/YSZ/Y2O3/NiW, in which the buffer layers are deposited by PLD, there occurs no self-epitaxy effect, and the optimal thickness of CeO2 is about 50 nm. The surface morphologies of the two groups of samples are examined by SEM. 相似文献
104.
辐照法制备交联聚丙烯酰胺涂层毛细管电泳柱及评价 总被引:2,自引:0,他引:2
采用辐照法制备交联聚丙烯酰胺毛细管电泳涂层柱。毛细管先经双功能团试剂γ-甲基丙烯基氧丙基三甲基硅烷预处理,然后柱内充入丙烯酰胺溶液进行辐照聚合,得到线性涂层柱;再经动态涂覆交联剂甲叉双丙烯酰胺,二次辐照交联,采用随机试验设计方法,对辐照剂量率,辐照时间和交联剂浓度几个因素进行了优化。 相似文献
105.
Using specially coated mirrors, an output energy of 0.97 J at 1.32 μm from a Nd3+∶YAG pulse laser is obtained with pumping energy of 66 J. The repetition rate is 1 pulse/sec and the slope efficiency is 1.7%. The repetition rate can be changed from 1 pulse/sec to 10 pulses/sec. 相似文献
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A highly sensitive analytical method for evaluation of poly(L-lactide) (PLA), poly(epsilon-caprolactone) (PCL), poly(beta-hydroxybutyrate) (PHB), and poly(butylene succinate) (PBS) degradability was developed using coated cellulose paper, prepared by penetration and adhesion of these plastics into/onto the cellulose paper. Enzymatic degradability of the obtained plastic coated papers was evaluated using various commercial proteases and lipases. PLA coated paper was highly susceptible to subtilisin and mammalian enzymes, alpha-chymotrypsin, elastase and trypsin. To our knowledge, this is the first report on the degradation of PLA coated paper using subtilisin and mammalian enzymes. Almost all lipase preparations degraded PCL and PHB coated papers but not PBS coated paper. The biodegradability of plastic coated paper was greater than that of plastic powder. The penetration of plastic into cellulose paper by coating improved the plastic degradability, and can be regulated easily. 相似文献
108.
HUA Feng-jun SUN Jun HONG Ke GAO Lian YANG Yu-liang ** . Key Laboratory of Molecular Engineering of Polymer Fudan University Shanghai P. R. China . State Key Laboratory of High Performance Ceramics Superfine Micros 《高等学校化学研究》2002,18(1):70-74
IntroductionTitanium dioxide with the rutile or the anatasestructure as,in principle,a white pigmentis widelyused as paints and plastic additives because of itshigh refractive index,oil adsorption,chemical orthermal stability[1— 4 ] .The most common manu- fac-ture of this material is based on the digestion of theore ilmenite(Fe O· Ti O) with sulfuric acid,fol-lowed by hydrolyzing the solution of titanium ionsand the calcination of the hydrous titanium ox-ides[5] .Another industrial prepara… 相似文献
109.
氧化锌包覆超细二氧化钛的制备及其紫外屏蔽性能 总被引:33,自引:0,他引:33
采用分步-均一沉淀法,以尿素为沉淀剂制备粒径为40nm的锐钛矿型二氧化钛超细粒子,并在其表面包覆晶体粒径为10.2nm的氧化锌,研究了不同含量的氧化锌对包覆效果及紫外吸收性能的影响.结果表明,合成的氧化锌包覆超细锐钛矿型TiO2的紫外吸收性能明显高于锐钛矿型超细二氧化钛、金红石型二氧化钛及市售氧化锌. 相似文献
110.
Low (15 nM) limits of detection (LOD) of dopamine were obtained at porous 1–3 nm‐thick overoxidized polypyrrole (OPPY) membrane‐coated microdisk carbon fiber electrodes of small size (r=3.5 µm). The excellent mass transport through the porous OPPY membrane (efficiency as good as solution transport) contributes to the low LOD, together with dopamine preconcentration in the membrane. Structural characterization of the membrane coated electrodes confirms the contribution of membrane nanostructure to the high sensitivity and the low LOD. 相似文献