用有效折射率／有限元法设计1．55μmTi：LiNbO_3单模条波导及其方向耦合器

应用有效折射率／有限元法（ＥＩ－ＦＥＭ），考虑到ＬｉＮｂＯ３晶体和Ｔｉ扩散的各向异性，折射率增量与寻常光、非寻常光及波长色散的关系，设计了１．５５μｍ光波长下工作的ｚ切ｙ传播Ｔｉ：ＬｉＮｂＯ３单模条波导的制备参数，计算和分析了其单模特性、模式场分布及其变化规律．扩展了ＥＩ－ＦＥＭ，将其用于求解耦合波导系统，确定了方向耦合器的耦合长度及其波长色散特性．     

电镀烧结法制备Ti/SnO2-Sb2O4电极的研究

The Ti/SnO₂-Sb₂O₄ electrode has been prepared by the electroplate-sinter method. The effect of SbCl₃ adding amount and sintering temperature on its electrode lifetime and oxygen evolution potential were investigated by means of EDX, SEM and XRD analysis. The results indicated that the electrode appeared the best performance when the SbCl₃ adding amounts was 0.2g and the sintering temperature was 550℃. In optimized conditions Ti substrate was entirely covered by SnO₂-Sb₂O₄ and the combinations among them were tight. Due to the use of electroplate method, the electrical conductivity, the oxygen evolution potential and the electrode lifetime were increased, so the elec-tro-catalytic activity and the electrochemical stability of the prepared electrode were found to be superior.     

Multilayered Cu–Ti deposition on silicon substrates for chemiresistor applications

Abstract

On the perspective to develop CuO–TiO₂ MOS, multilayered Cu and Ti thin layers were alternatively deposited on silicon wafers using 25?keV Ar?+?ion beam sputtering and, subsequently, oxidized by thermal annealing in air at 400?°C for 24?h. The deposited films have variable ratios of the Cu and Ti % at. One of the main goal is to obtain such multilayers avoiding the presence of Cu–Ti–O compounds. The samples were characterized in terms of composition (by RBS and SIMS analyses) and morphology (by AFM and SEM investigations). In particular, SIMS maps allows to observe the spatial distribution and thickness of each phase of the Cu/Ti multilayers, and further to observe Cu diffusion and mixing with Ti, as well as phase separation of CuO and TiO₂ in the samples. The reasons of this effect represent an open issue that has to investigated, in order to improve the MOS fabrication.     

A new route of the reaction of EtAlCl2 with α-olefins catalyzed by Ti complexes

A new method for the synthesis of dialkyl(ethyl)alanes by the reaction of EtAlCl₂ with -olefins in the presence of Mg and a catalytic amount of Cp₂TiCl₂ (Ti(OPrⁱ)₄, Ti(OBuⁿ)₄) in THF was developed.     

Structure of Sol-Gel-Derived Sodium Dititanate Glass

The sodium dititanate, Na₂O·2TiO₂ glass was prepared by the sol-gel method. The structure of the glass, especially local environment of Ti⁴⁺ ions was examined using X-ray diffraction and X-ray absorption fine structure (XAFS) analyses, and was compared with that of the melt-derived glass with the same composition. It was found that Ti⁴⁺ ions are rather in five-fold coordination state, forming TiO₅ pyramids with one doubly bonded Ti=O in the gel-glass, while they were in lower coordination state or four-fold coordination in the melt-derived glass.     

钇对金属陶瓷力学性能和组织的影响

研究了添加钇对Ｔｉ（Ｃ，Ｎ）基金属瓷力学性能和组织的影响。结果表明，加入适量的钇能提高Ｔｉ（Ｃ，Ｎ）基金属陶瓷的抗变强度和硬度，其原因是由于钇与杂质硫起反应在化合物，净化了陶瓷相－金属相，陶瓷相－陶瓷相界面提高子界面结合强度     

Titanium‐implanted CaTiO3 films and their changes in Hanks' solution

Titanium‐implanted CaTiO₃ film was prepared and then characterized by x‐ray photoelectron spectroscopy (XPS) and Rutherford backscattering spectrometry (RBS) before and after immersion in Hanks' solution for 7 days. An as‐prepared specimen contained a small amount of Ar implanted during sputtering, although the pressure was as low as 10^?4 Torr. Even though Ar convolution increased with an increase in the relative Ti ion dose, most of the convoluted Ar was not from the Ar gas used for Ti ion production but rather was from the Ar gas used for sputtering the CaTiO₃. During Ti implantation, the CaTiO₃ films were ion‐etched by Ti ions. The composition of the CaTiO₃ film was not changed to any great degree by the Ti implantation, however its properties changed considerably. After immersion in Hanks' solution, the thickness of the specimen not implanted with Ti decreased the most whereas the [Ca]/[P] ratio, which was nearly unity before exposure, decreased significantly, becoming 0.23 on the Ti‐implanted specimen prepared at 200 W and 0.13 on the Ti‐implanted specimen prepared at 50 W. It was also observed by XPS that the ratio [Ca]/[P] was ～1.9 for all Ti‐implanted specimens after immersion in Hanks' solution for 7 days. Judging from the binding energies of Ca 2p_3/2 and P 2p electrons and the [Ca]/[P] ratio, it was suggested that a hydroxyapatite‐like substance had formed on the surfaces of the Ti‐implanted specimens after immersion in Hanks' solution. Copyright © 2003 John Wiley & Sons, Ltd.     

Influence of the cathodic polarization on the stability of Ti surface in concentrated KOH solutions

The stability of spontaneous thin layers and thin layers formed upon cathodical polarization of Ti in KOH solutions have been studied by potentiostatic and ellipsometric methods. At open circuit potential (OCP) the strongly adherent films, whose thickness depends on the concentration of the KOH solution, were formed. During the cathodic polarization the transformation of these films to weakly adsorbed precipitated layers on the electrode surface was observed. Comparing the theoretically computed curves with the experimental Ψ vs Δ loci measured ellipsometrically, the complex indices of refraction and the thickness of the generated films, from 3.6 to 60 nm in 1 M KOH and from 36 to 105 nm in 5 M KOH (adherent to the electrode surface), were determined. At OCP the rate of film growth increases with increasing the concentration of KOH solution. Cathodic polarizations change the chemical composition and retard the rate of film growth. Based on the ellipsometric and electrochemical data the chemical compositions of the formed films consisted of TiO₂, Ti₂O₃, TiO₂·H₂O, Ti(OH)₃ and TiOOH·nH₂O.     

Ti2(OMe)4/SiO2催化剂的制备及其合成碳酸二甲酯的反应性能

采用表面改性和离子交换法制备了SiO2负载的Ti2(OMe)4双核桥联配合物催化剂，用IR、TPD和微反技术考察了催化剂的表面构造及CO2和CH3OH在催化剂表面上的化学吸附和反应性能。结果表明：双核桥联配合物Ti2(OMe)4以Ti-O-Si键锚定在SiO2表面上；CO2在催化剂表面存在桥式和甲氧碳酸酯基两种吸附态，其中甲氧碳酸酯基吸附态是生成DMC的关键物种；CH3OH在催化剂上只有一种分子吸附态。在150℃以下，CO2和CH3OH在Ti2(OMe)4/SiO2催化剂表面上高选择地生成碳酸二甲酯。     

稀土在低硫铌钛钢中的作用

在实验条件下采用50kg真空感应炉炼和两段控制轧制工艺，并采用WE－60型万能拉伸试验机，JB－30B型冲击试验机，MM6型及OLYMPUS－PME3型光学金相显微镜，IBAS－2000图相分析等手段研究了稀土对低硫铌钛钢性能，组织及夹杂物的影响。在低硫铌钛钢中的试验结果表明，稀土元素的加入使力学性能变化各异，它使钢的横向屈服点和抗拉强度先下降而后上升；延伸率则无下降而后上升；稀土对钢的横向冲击功则表现为先上升而后下降，并且在－20℃以上，适量的稀土加入可以明显改善其冲击功的各向异性；稀土的加入并不能改变钢的显微组织类型，钢的组织为铁素体＋珠光体，但稀土会使钢中珠光体数量增加，铁素体数量减少，在钢中夹杂物方面，稀土加入则表现为它一方面 化钢液，使钢中夹杂物数量减少，另一方面是使钢中夹杂物的颗粒球化，细化和弥散化，从而改善夹杂物的分布。