Effect of fluoride ions on coordination structure of titanium in molten NaCl–KCl

The effects of fluoride ions(F^(-)) on the electrochemical behavior and coordination properties of titanium ions(Ti^(n+)) were studied in this work,by combining electrochemical and mathematical analysis as well as spectral techniques.The α was taken as a factor to indicate the molar concentration ratio of F^(-) and Ti^(n+).Cyclic voltammetry(CV),square wave voltammetry(SWV),and open circuit potential method(OCP)were used to study the electrochemical behavior of titanium ions under conditions of various α,and in-situ sampler was used to prepare molten salt samples when α equal to 0.0,1.0,2.0,3.0,4.0,5.0,6.0,and 8.0.And then,samples were analyzed by X-ray photoelectron spectroscopy(XPS) and Raman spectroscopy.The results showed that F^(-) in molten salt can reduce the reduction steps of titanium ions and greatly affects the proportion of valence titanium ions which making the high-valence titanium content increased and more stable.Ti^(2+) cannot be detected in the molten salt when α is higher than 3.0 and finally transferred to titanium ions with higher valence state.Investigation revealed that the mechanism behind those phenomenon is the coordination compounds(TiCl_(j) F_(i)^(m-)) forming.

Effects of Ti_(0.5)Al_(0.5)N coatings on the protecting against oxidation for titanium alloys

Ti0.5Al0.5N coatings were deposited on TC11（Ti-6.5Al-3.5Mo-1.5Zr-0.3Si） and silicon substrates using a cathode arc ion-plating system.The microstructure, composition, phase structure, and oxidation-resistance of the alloys and nitride coatings were investigated by scanning electron microscopy, X-ray diffraction, transmission electron microscopy, Auger electron spectroscopy, and thermal analyzer.The results show that the oxidation resistance of the titanium alloy is relatively limited;the compound structures of Ti mixed with Al oxides are formed during the heating process.The phases of the Ti0.5Al0.5N coatings are composed of a TiN solid solution phase.The oxidation kinetics obeys the parabolic law.During the oxidation process, the selective oxidation of Al occurs, thus protecting the underlying coating and substrate.

COMPARISON OF SURFACE PROPERTIES OF Ti-6Al-4V COATED WITH TITANIUM NITRIDE, TiN+TiC+Ti(C,N)/DLC, TiN/DLC AND TiC/DLC FILMS BY PLASMA-BASED ION IMPLANTATION

The surface properties of Ti-6Al-4V alloy coated with titanium nitride, TiN+TiC+Ti(C,N)/DLC (diamond like carbon), TiN/DLC and TiC/DLC films by plasma-based ion implantation (PBII) with nitrogen, PBII with nitrogen then acetylene, PBII with nitrogen then glow discharge deposition with acetylene plus hydrogen and PBII with acetylene then glow discharge deposition with acetylene plus hydrogen respectively were studied. The corresponding films are found getting dimmer, showing light gold or gold, smoky color (uneven), light red in black (uneven), and graphite black separately. The corresponding film resistivities are given. Antioxidation ability of the titanium nitride film is poor, while the existence of carbon (or carbide) improves the antioxidation ability of the films. Having undergone excellent intermediate transitional region of nitrogen and carbon implantation, the top DLC layer of the TiN+TiC+Ti(C,N)/DLC multilayer are formed after the carbon implantation has the best adhesion with the substrate among all the multilayers. Although microhardness of the samples increases in the order of coatings of titanium nitride, TiN/DLC, TiN+TiC+Ti(C,N)/DLC and TiC/DLC, the TiN/DLC and TiC/DLC multilayers have greater brittleness as compared with other films.

Photocatalytic degradation of Rhodamine B under visible light with Nd-doped titanium dioxide films

Microporous titanium dioxide films were prepared by the sol-gel methods on glass substrates, using tetrabutyl titanate as source material. In order to absorb the visible light and increase the photocatalytic activities, different concentrations of neodymium ions (Nd/Ti molar ratio was 0.5%, 0.7%, 0.9%, and 1.1% respectively) were added into the sol. X-ray diffraction (XRD), X-ray photoelectron spectros-copy (XPS), and atom force microscopy (AFM) were applied to characterize the modified films. A kind of typical textile industry pollutant (Rhodamine B) was used to evaluate the photocatalytic activities of the films under visible light. The results showed that the activities of the films were improved by doping Nd ions into the sol.

Improvement on electrochemical performances of nanoporous titania as anode of lithium-ion batteries through annealing of pure titanium foils

The effect of annealing of Ti foils before anodization on the morphology and electrochemical performance of resultant nanoporous anatase TiO2 （np-TiO2） as anode in rechargeable lithium-ion batteries （LIBs） was investigated. The np-TiO2 anode fabricated from annealed Ti foils exhibited higher specific surface area and reduced pore diameter compared to np-TiO2 electrode fabricated from as-received Ti foils. The highly porous np-TiO2 anode fabricated from annealed Ti foils exhibited 1st discharge capacity of 453.25 mAh/g and reduced to 172.70 mAh/g at 1 C current rate after 300 cycles; whilst the np-TiO2 electrode fabricated from the as-received Ti foils exhibited 1st discharge capacity of 213.30 mAh/g and reduced to 160.0 mAh/g at 1 C current rate after 300cycles. Even after 400cycles, such np-TiO2 electrode exhibited a reversible capacity of 125.0 mAh/g at 2.5 C current rate. Compared to the untreated Ti foils, the enhanced electro- chemical performance of np-TiO2 anode fabricated from annealed Ti foils was ascribed to the annealing- induced removal of residual stress among the Ti atoms. The benefit of annealing process can reduce pore size of as-fabricated np-TiO2.

Fabrication of anatase titanium dioxide nanotubes by electroless deposition using polycarbonate for separate casting method

Titanium dioxide nanotubes(TNTs)were prepared by electroless deposition using ion track etched polycarbonate templates.The ion tracks were prepared to the desired diameter of the TNTs outer diameter.Titanium dioxide nanotubes with a diameter of minimum 80 nm having a wall thickness of minimum 10 nm can be fabricated using this method.To achieve nanotubes with thin walls and small surface roughness the tubes were generated by a several steps procedure under aqueous conditions at nearly room temperature.The presented approach will process open end nanotubes with well defined outer diameter and wall thickness.Using this method TNT arrays up to 109 tubes per cm2having a tube length up to 30μm can be produced,single tubes are also possible.The structural properties of the grown TNTs were investigated by using various analytical techniques,i.e.scanning electron microscopy(SEM),energy dispersive X-ray fluoresence spectrometer(EDX),X-ray photoelectron spectroscopy(XPS),X-ray diffraction(XRD),Raman spectroscopy and Photoluminescence.

Adsorption of uranyl complex ions on hydrous titanium oxide (HTO)——Ⅱ Infrared spectrum investigation

-The i. r. spectra of Na4 [UO2 (CO3)3], Na [UO2 (OH)3] and the surface species of uranium on HTO underthe condition of flowing natural seawater and concentrated seawater (NaCl-NaHCO3-U) were recorded, with the bands of urany! of surface species obtained and the finding that iigands of surface species besides HTO are mainly water and OH, and there are some CO32- groups under the condition of natural seawater. Some relations between the complex properties and the j. r. spectroscopic characters for uranyl complexes were studied, and the transferred change quantity of surface complex was calculated.Structure models for surface species of adsorption are herein presented and the mechanism for uranium adsorption is deduced.

SURFACE MODIFICATION OF TITANIUM FILMS WITH SODIUM ION IMPLANTATION:SURFACE PROPERTIES AND PROTEIN ADSORPTION

Sodium implanted titanium films with different ion doses were characterized to correlate their ion implantation parameters. Native titanium films and ion implanted titanium films were characterized with combined techniques of X-ray photoelectron spectroscopy （XPS）, atomic force microscopy （AFM）, and light microscopy （LM）. The surface presented increased sodium concentration on treated titanium films with ion dose increasing, except for the group with the highest ion dose of 4×10^17ions/cm^2. XPS depth profiling displayed that sodium entered titanium film around 25-50nm depth depending on its implantation ion dose. AFM characterization showed that sodium ion implantation treatment changed the surface morphology from a relatively smooth titanium film to rough surfaces corresponding to different implantation doses. After sodium implantation, implanted titanium films presented big particles with island structure morphology. The surface morphology and particle growth displayed the corresponding trend. Fibrinogen adsorption on these titanium films was performed to correlate with the surface properties of treated titanium films. The results show that protein adsorption on ion-implanted samples with dose of 2×10^17 and 4×10^17 are statistically higher （p 〈0.01） than samples treated with dose of 5×10^16 and 1×10^17, as well as the control samples.

REDUCTION OF FERRIC IRON IN THE TITANIUM SULFATE SOLUTION BY THE ION EXCHANGE MEMBRANE PRIMARY CELL METHOD

In the production process of titanium dioxide with sulfuric acid, the contamination of the titanium sulfate solution (the ilmenite leaching solution) in the Fe 3+ reduction stage by iron scraps is a practical problem because it is difficult to guarantee the quality of the iron scraps. In this research, a new method, called the ion exchange membrane primary cell method, for reduction of Fe 3+ in the titanium sulfate solution has been advanced. The positive compartment of the primary cell consists of lead (copper) electrode and the titanium sulfate solution, and the negative compartment consists of iron electrode and acidic FeSO 4 solution. The anion ion exchange membrane is used as the diaphragm between two compartments. Fe 3+ in the titanium sulfate solution is reduced by the electric discharge of the primary cell. The effects of temperature, stirring strength of the solution and membrane area on the reduction rate have been investigated. The experimental result shows that the optimum current density can be higher than 100 A/m 2.

Hydrodynamic Effects on Surface Morphology Evolution of Titanium Alloy under Intense Pulsed Ion Beam Irradiation

The hydrodynamic effects of molten surface of titanium alloy on the morphology evolution by intense pulsed ion beam （IPIB） irradiation are studied. It is experimentally revealed that under irradiation of IPIB pulses, the surface morphology of titanium alloy in a spatial scale of μm exhibits an obvious smoothening trend. The mechanism of this phenomenon is explained by the mass transfer caused by the surface tension of molten metal. Hydrodynamic simulation with a combination of the finite element method and the level set method reveals that the change in curvature on the molten surface leads to uneven distribution of surface tension. Mass transfer is caused by the relief of surface tension, and meanwhile a flattening trend in the surface morphology evolution is achieved.

Structural and Crystallographic Features of Chemically Synthesized Cero- and Titanium Cero- Antimonates Inorganic Ion Exchangers and Its Applications

Chemically synthesized cero-antimonate and titanium cero-antimonate prepared by sol-gel technique was conducted for the synthesis of a novel ion exchanger. The prepared materials has been characterized by X-ray diffraction, X-ray fluorescence, Fourier transform Infrared Spectroscopy (FT-IR) and Thermograve-metric analyses. The structures and empirical formula's was identified and found to CeSb4O12?6.19H2O and TiCeSb4O14?12.22H2O, for cero-antiomate and titanium cero-antimonate, respectively. The data obtained from X-ray diffraction was analyzed to define the crystallographic feature of cero-antimonate and titanium cero-antimonate and found both the composites were belong to cubic system with lattice constant 5.15 and 5.149 ?, respectively. The crystallite size and strain of cero-antimonate and titanium cero-antimonate were determined. By using ChemDraw Ultra program the modeling structures of cero-antimonate and titanium cero-antimonate were conducted. Finally, application of the prepared materials for the removal of heavy metals from industrial waste water in terms of capacity measurements was performed.

Two-dimensional numerical research on effects of titanium target bombarded by TEMPⅡ accelerator

Two-dimensional numerical research has been carried out on the ablation effects of titanium target irradiated by intense pulsed ion beam （IPIB） generated by TEMP Ⅱ accelerator. Temporal and spatial evolution of the ablation process of the target during a pulse time has been simulated. We have come to the conclusion that the melting and evaporating process begin from the surface and the target is ablated layer by layer when the target is irradiated by the IPIB. Meanwhile, we also obtained the result that the average ablation velocity in target central region is about 10 m/s, which is far less than the ejection velocity of the plume plasma formed by irradiation. Different effects have been compared to the different ratio of the ions and different energy density of IPIB while the target is irradiated by pulsed beams.

Equilibrium State of Anatase to Rutile Transformation for Titanium Dioxide Film Prepared by Ultrasonic Spray Pyrolysis Technique

Titanium dioxide thin films were deposited on (0001) α-quartz substrate by spray pyrolysis method. The method which an aerosol of Titanium Butoxide, generated ultrasonically, was sprayed on the substrate at temperature of 400°C, kept at this temperature for periods of 3, 13, 19 and 39 hours. The developed films at a crystal phase correspond to the TiO2 anatase and rutile phases. Their surface roughness increased by annealing the samples at 600, 800 and 1000°C. Deposited film annealed at 1000°C showed preferable orientation in (110) direction. The crystal evolution and crystallographic properties of this material was studied by Lotgering method, X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The study revealed that the deposition process was nearly close to the classical Chemical Vapour Deposition (CVD) technique that is generally employed to produce films with smooth surface and good crystalline properties with a thickness of about 1 μm, as measured by Focused Ion Beam.

钛表面多酚介导铜离子涂层制备及抗菌抗氧化性能

背景:钛植入体因比强度高及良好的生物相容性被广泛应用于临床,然而在植入手术过程中,细菌感染及组织受损环境产生大量活性氧物质易导致组织延迟愈合与手术失败,因此开发具有抗菌和抗氧化性能的钛植入体极为重要。目的:鉴于铜离子良好的抗菌性能及多酚类物质优良的抗氧化性能,拟在钛表面制备多酚介导的铜离子涂层,评价其体外抗菌及抗氧化性能。方法:利用碱热法在钛表面制备纳米结构,然后将钛片置于单宁酸及铜离子溶液中,获得多酚介导的铜离子涂层,检测样品的表面形貌与水接触角,利用原子吸收光谱法检测铜离子的携载及释放。将金黄色葡萄球菌分别接种于纯钛片(空白组)、碱热处理钛片(对照组)、多酚介导的铜离子修饰钛片(实验组)表面,观察细菌存活状态。将成骨前体细胞MC3T3-E1分别接种于3组钛片表面,评价材料的抗氧化性能及生物活性。结果与结论:(1)扫描电镜下可见多酚介导的铜离子修饰钛片表面存在棒状纳米结构,并且涂层无裂纹;多酚介导的铜离子修饰钛片表面亲水性接近纯钛片;原子吸收光谱结果显示,多酚介导后钛片表面铜离子的携载量增加了51%,铜离子呈均匀释放。(2)空白组、对照组、实验组钛片的抗菌率为0%,21.65%,93.75%;活死染色与CTC染色显示,空白组钛片表面的活细菌最多,实验组钛片表面的活细菌最少。(3)活死染色与CCK-8检测结果显示,3组钛片均具有良好的细胞相容性,并且实验组钛片更有利于MC3T3-E1细胞增殖;活性氧荧光探针检测显示,相较于其他两组,实验组钛片表面活性氧荧光强度明显减弱;碱性磷酸酶与茜素红S染色结果显示,相较于其他两组,实验组钛片表面MC3T3-E1细胞的成骨分化与细胞外基质矿化能力更强。(4)结果表明,多酚介导的铜离子涂层具有较强的抗菌、抗氧化及促成骨分化性能。

聚砜作粘结剂的锂离子筛粉体的高性能造粒研究

用于盐湖提锂的钛系锂离子筛(β-H_(2)TiO_(3))粉体的尺寸属于微纳米级别,需要对其进行颗粒化成型才能填柱使用。针对β-H_(2)TiO_(3)的实际应用工况(碱性环境提锂,酸性环境脱锂),采用可耐酸碱的聚砜(PSF)作为粘结剂对β-H_(2)TiO_(3)粉体进行滴粒成型。通过探究PSF用量、N,N-二甲基乙酰胺(DMAC)用量、聚乙烯吡咯烷酮(PVP-K15)用量、凝胶浴温度及滴粒针孔直径对β-H_(2)TiO_(3)-PSF颗粒性能的影响,确定滴粒成型的配方及工艺。获得的β-H_(2)TiO_(3)-PSF颗粒对Li^(+)的体积吸附容量为4.70g/L,堆积密度为0.455kg/L,且该材料在循环100次后,体积吸附容量仍为原来的95%。

XiPAF重离子同步加速器超高真空系统设计

在重离子同步加速器运行过程中需要维持超高真空,降低束流与残余气体的碰撞概率,从而提高束流寿命。具体要求一般为:真空管道内的平均真空度达到超高真空度(10^(–10)Pa量级),并且管道内各处真空度均优于设计值。本文研究了重离子同步加速器中超高真空系统的实现方法,即使真空泵不能均匀分布在束线上,也可以实现真空管道内各处真空度均优于设计指标。采用的主要技术路线是,降低束流管道材料的比放气率,同时增大真空泵组的抽速。具体实施方案是:通过在真空管道内表面镀非蒸发型吸气剂(NEG)薄膜及高温烘烤真空管道降低束流管道材料的比放气率;设计使用大抽速钛升华泵(TSP)以增加真空泵抽速。其中,NEG镀膜技术既可以阻隔真空管道内壁的放气,又有吸气的效果,可以提高真空管道内各处的真空度。以上超高真空系统实现方法已应用于西安200 MeV质子应用装置(XiPAF)重离子升级工程中的重离子同步加速器的真空系统设计。真空管道内表面的NEG薄膜的吸速为0.5 L/(s·cm^(2));在重离子同步加速器上配置36台钛升华泵,每台钛升华泵对氢气的有效抽气量为2200 L/s;应用Molflow+软件模拟XiPAF重离子同步加速器真空管道内部的真空度分布。通过设计优化,计算表明该加速器在运行时预计平均真空度可以小于5×10^(–10)Pa,沿环形管道各处的真空度也均小于5×10^(–10)Pa,满足同步环物理设计要求。

超高真空环境下TC4钛合金和ZrO_(2)陶瓷的出气性能研究

内衬超薄壁真空腔体是离子加速器真空系统的核心元件,为了获得超高真空环境,对内衬材料的出气性能有较高要求。基于新型双通道出气率实验装置,完成了TC4钛合金和ZrO_(2)陶瓷在常温抽气、不同烘烤温度及烘烤结束后不同温度下的出气率实验;通过数值拟合方法获得了材料在不同加热温度下的出气率表达式;搭建了钛合金内衬超薄壁真空腔体压力实验装置,通过实验和仿真对比分析了不同工况下的压力分布。结果表明,烘烤温度越高,最终出气率越低,250℃烘烤时出气率较150℃时降低了约21%。经过高温烘烤后,当材料温度从50℃升高至210℃时,两种材料的出气率呈指数增加趋势,但钛合金的出气率低于陶瓷的出气率。常温抽气和烘烤过程中真空腔体压力梯度较小,对其进行升温时中间位置压力变化幅度较大,当温度为100℃,中间位置压力从初始值1.41×10^(-9)Pa升高至4.51×10^(-9)Pa;压力仿真结果和实验结果一致,平均相对偏差为6.86%。以上结果填补了钛合金和陶瓷出气率数据库,能够预测及评估真空腔体不同工况下的极限压力,为超高、极高真空获取提供数据支撑。

Microanalysis on the Hydrogen Ion Irradiated 50 wt pct TiC-C Films

The 50 wt pct TiC-C films were prepared on stainless steel substrates by using a technique of ion beam mixing. These films were irradiated by hydrogen ion beam with a dose of 1×10^18 ions/cm^2 and an energy of 5 keV. Microanalysis of X-ray photoelectron spectroscopy （XPS） and secondary ion mass spectroscopy （SIMS） were used to analyze the films before and after hydrogen ion irradiation and to study the mechanism of hydrogen resistance.

Preparation of anatase TiO_2 with assistance of surfactant OP-10 and its electrochemical properties as an anode material for lithium ion batteries

With the assistance of nonionic surfactant （OP-10） and surface-selective surfactant （CH3COOH）, anatase TiO2 was prepared as an anode material for lithium ion batteries. The morphology, the crystal structure, and the electrochemical properties of the prepared anatase TiO2 were characterized by scanning electron microscopy （SEM）, X-ray diffraction （XRD）, electrochemical impedance spectroscopy （EIS）, and galvanostatic charge and discharge test. The result shows that the prepared anatase TiO2 has high discharge capacity and good cyclic stability. The maximum discharge capacity is 313 mAh.g^-1, and there is no significant capacity decay from the second cycle.

Surface modification of Ti-49.8at%Ni alloy by Ti ion implantation: phase transformation, corrosion, and cell behavior

The Ti-49.8at%Ni alloy was modified by Ti ion implantation to improve its corrosion resistance and biocompatibility. The chemical composition and morphologies of the Ti Ni alloy surface were determined using atomic force microscopy(AFM), auger electron spectroscopy(AES), and X-ray photoelectron spectroscopy(XPS). The results revealed that Ti ion implantation caused the reduction of Ni concentration and the formation of a Ti O2 nano-film on the Ti Ni alloy. The phase transformation temperatures of the Ti–Ti Ni alloy remained almost invariable after Ti ion implantation. Electrochemical tests indicated that the corrosion resistance of Ti Ni increased after Ti ion implantation. Moreover, the Ni ion release rate in 0.9% Na Cl solution for the Ti Ni alloy remarkably decreased due to the barrier effect of the Ti O2 nano-film. The cell proliferation behavior on Ti-implanted Ti Ni was better than that on the untreated Ti Ni after cell culture for 1 d and 3 d.