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141.
Wenfeng Liu Yuesheng Chai Gang Sun Mingang Zhang College of Materials Science Engineering Taiyuan University of Science Technology Taiyuan China 《材料科学技术学报》2009,(6)
[AlN/FePt] 10 , [AlN/FePt] 10 /Ag and Ag/[AlN/FePt] 10 thin films were deposited by magnetron sputtering onto 7059 glass substrates, then were annealed at 550 °C for 30 min. It is found that introducing non-magnetic Ag underlayer can improve the ordering and (001) preferred orientation of FePt grains. Furthermore, the (001) texture of FePt grains increases with increasing Ag underlayer thickness. However, with Ag top layer given, it can only be observed that the ordering of FePt grains was promoted. 相似文献
142.
通过静态吸附和动态吸附实验,研究温度、pH值、稀释倍数和流速对001×8树脂从离子型稀土浸出液中吸附稀土与杂质离子的吸附量及分离系数的影响. 结果表明:浸出液中稀土与杂质离子的吸附量及分离系数随着pH值的增大呈现出先增大而后减小的趋势,在pH值为3.5时达到最大值;随着温度的升高而增大,吸附量在313 K后逐渐趋于平衡. 树脂对各离子吸附能力大小为: RE3+>Al3+>Mg2+>SiO32-. RE3+、SiO32-和Al3+的吸附量随着稀释倍数的加大而增大,随着流速的加快而减小,而Mg2+的吸附量随着稀释倍数的加大或流速的加快而减小. 因此,增大稀释倍数和降低流速有利于001×8树脂吸附稀土和除去杂质. 相似文献
143.
144.
WU Peiwen HU Xuerang QIAN Jun YUAN Jun 《稀有金属(英文版)》2006,25(3):260-264
A nonepitaxial (001) textured Fe-Pt alloyed film was obtained by annealing Fe/Pt multilayers in H2. No Such nonepitaxial (001) texture was observed for similar multilayers annealed in N2 atmosphere. Sensitive electron energy loss spectroscopy and the left shift of the L10 FePt (111) diffr cfion peak indicate oxidation in the N2 annealed samples. The oxidation dramatically degrades the (001) texture of the Fe-Pt fdm and induces the composition change in the alloyed layer. The relation between the texture formation and oxidation was discussed. 相似文献
145.
使用定向生长的[001]对称倾侧Cu双晶,研究了Bi偏聚对Cu双晶断裂行为和晶界脆性的影响.结果表明:Cu-Bi双晶的断裂行为和断裂应力强烈地依赖于晶界的取向差,而与晶界的重位点阵密度无关,其晶界脆性取决于未偏聚Cu双晶晶界的能量.晶界的能量越大,晶界脆性越强.这种依赖关系可由Bi在不同晶界的选择性偏聚解释. 相似文献
146.
采用多次阳极氧化技术,在金属钛表面制备(001)晶面族择优生长的TiO_2纳米管阵列,研究电解液成分对锐钛矿TiO_2不同晶面相对比例的影响并考察其生物学活性。采用扫描电镜(SEM)、X射线衍射(XRD)等方法分析纳米管阵列的形貌特征和晶体结构,通过生物矿化CaP盐的沉积和蛋白吸附实验评价样品晶面对生物活性的影响。结果表明:通过改变电解液中H_2O的含量,能够便捷调控锐钛矿TiO_2纳米管中不同晶面的相对比例。当H_2O含量为2%(体积分数)时,制备得到的TiO_2纳米管阵列(004)晶面的织构系数Tc(004)可达4.76。而具有(001)优势晶面族的TiO_2纳米管,在类人体环境中能够为生物矿化和蛋白吸附提供更多的活性位点,加速羟基磷灰石的沉积并增加蛋白吸附量,表现出更优异的生物学活性。 相似文献
147.
The atomic arrangement of the Si(001)-(2 times 8) surface has been directly imaged in real space by scanning tunnelling microscopy. The superstructure is impurity induced and stablilized by as little as 1% Ni. Clean Si(001) surfaces do not form the (2times8) phase. The two-dimensional Fourier transforms of the STM topographs correspond well to the (2times8) LEED pattern, but the real space images are in fact considerably more complex than previously concluded on the basis of recent diffraction technique measurements. The STM images clearly demonstrate that the (2times8) surface consists of a complex missing dimer structure, namely one and multiple dimer vacancies. Such a dimer defect appears related to the Ni impurity and intimately related to the ordering of the dimer defects probably by third layer dimerization to produce quasi-ordered ‘channels’. 相似文献
148.
This paper reports the synthesis of nanosized TiO2 single crystals with different percentages of exposed (001) facets in the presence of HF solution. Various characterizations are conducted to understand the correlation between particle morphology, exposed (001) facets and photo‐conversion efficiency of the nanosized anatase TiO2 single crystals. An enhancement in dye‐sensitized solar cells (DSSCs) overall conversion efficiency is observed for the photoanode consisting of nanosized TiO2 single crystals with higher percentage of exposed (001) facets, increasing from 7.47%, 8.14% to 8.49% for the TiO2 single crystals with ca. 10%, 38%, and 80% percentage of exposed (001) facets. Experimentally confirmed by dark current potential and open‐circuit voltage decay scans, such highly exposed (001) facets are not only favorable for more dye adsorption but also effectively retard the charge recombination process in DSSCs. 相似文献
149.
多年来,国内外学者不断致力于常规与非常规油气资源烃源岩的评价与研究,烃源岩评价离不开有机质的类型、丰度、成熟度和厚度的研究。对于有机质丰度的研究关键参数是总有机碳含量(TOC)的计算。利用测井资料可以先定性后定量评价烃源岩,富含有机质的烃源岩,在常规测井曲线上表现为:高放射性强度、低补偿密度(DEN)、高声波时差(AC)、高补偿中子(CNL)、高电阻率(Rt)等特征。研究综合了鄂尔多斯盆地二叠系太原组—山西组烃源岩自然伽马能谱测井测量的钍(Th)、铀(U)和AC、Rt曲线,提出以Th/U结合△LogR模型为基础,根据多元回归研究方法确定TOC的计算模型。利用该模型对Y88井太原组—山西组的TOC进行了计算,并对其计算结果和岩心分析进行了对比,结果显示绝对误差大部分低于0.5。将该模型推广应用到其他井数据中,处理结果在误差允许的范围内,该模型具有较强的适用性和可靠性。 相似文献
150.
Zhouyou Wang Ze-Xian Low Xiangkang Zeng Bin Su Yichun Yin Chenghua Sun Tim Williams Huanting Wang Xiwang Zhang 《International Journal of Hydrogen Energy》2018,43(3):1508-1515
TiO2 nanosheets with high ratio of {001} facets were coupled with reduced graphene oxide (rGO) nanosheets through the link of silver (Ag) nanoparticles, forming a novel ternary nanocomposite photocatalyst with a vertical heterostructure, TiO2-Ag-rGO. The vertical anchoring of TiO2-Ag nanosheets between rGO sheets was confirmed by transmission electron microscopy (TEM), Raman spectroscopy, energy dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). Due to excellent separation of electron-hole pairs in the TiO2 nanosheets, enhanced electron transfer to rGO via Ag nanoparticles, the TiO2-Ag-rGO nanocomposite exhibited an outstanding performance in photocatalytic hydrogen production, with a hydrogen production rate of 593.56 μmol g?1 h?1. This study provides new insights to the development of Pt-free photocatalysts for hydrogen production. 相似文献