Ti6Al4V表面双层辉光离子渗Mo及其摩擦学性能的研究

利用双层解光离子渗金属技术在Ti6A14V合金表面渗Mo，用球—盘磨损试验机对试样的摩擦性能进行了研究．结果表明：Ti6A14V合金表面渗Mo可以形成均匀的表面改性合金层，合金层由沉积层和扩散层构成；合金层的硬度和弹性模量分别为10．86GPa和278．84GPa，较Ti6A14V有较大提高；渗Mo后的试样在干摩擦小滑动距离下表现出一定的减摩作用，耐磨性明显增强；在油润滑条件下，渗Mo改性层具有优异的减摩和耐磨性能．     

负载CuO的Ti~(3+)/TiO_2催化剂制备及其光催化甲苯降解性能

通过在锐钛矿TiO_2载体表面上负载Cu-BTC(BTC,1,3,5-苯甲酸)前驱体,还原处理制备光催化剂CuO-Ti~(3+)/TiO_2(Cu-TiMB),对其在可见光条件下气相甲苯净化催化性能进行了研究。结果表明,该改良方法制备的CuO-Ti~(3+)/TiO_2(CuTiM B)催化剂的活性是浸渍法所得催化剂CuO-TiO_2(Cu-TiD)的2.68倍。CuO-Ti~(3+)/TiO_2(Cu-TiMB)具有更大的比表面积(147 m2/g)和较小的颗粒粒径(0.45μm),呈现多孔状,CuO的分散度较高;催化剂表面Ti~(3+)提供了大量的氧缺位,在400-800 nm波段的光响应能力显著增强。CuO-Ti~(3+)/TiO_2(Cu-TiMB)催化剂中Cu~(2+)、Cu~+与Ti~(3+)形成的异质结构进一步增多了氧缺位数量,延缓e--h+的复合时间;氧缺陷增强了捕获吸附氧能力,通过金属氧化物价态变化增强化学吸附能力,提高了光催化性能。     

新型荧光粉Ca2Zn4Ti16O38∶Pr3+，Na+的合成和红色长余辉性质

采用溶胶-凝胶法合成了Ca2Zn4Ti16O38:Pr3+,Na+荧光粉.通过X-射线衍射和荧光光谱表征样品的物相组成和发光性质.X射线衍射(XRD)分析表明添加适量的H3BO3作助熔剂有利于形成良好的Ca2Zn4Ti16O38晶体结构.荧光光谱表明Ca2Zn4Ti16O38:Pr3+,Na+在可见光区(450～495 nm)呈现Pr3+离子的4f→4f厂特征激发光谱以及613 nm(1D2→3H4)和644 nm(3P0→3F2)特征发射.Ca2Zn4Ti16O38:Pr3+,Na+被可见光(475 nm)激发产生的(3P0→3F2)(644 nm)红色发射呈现出极慢的衰减特性.Ca2Zn4Ti16O38:Pr3+,Na+是一种新型的可见光激发红色长余辉荧光粉.     

V-5Cr-5Ti合金弹性和力学性质的第一性原理研究

V-5Cr-5Ti合金作为核聚变堆第一包层的主要候选结构材料之一,但对其力学性质的理论研究相对较少.采用随机固溶体模型,利用第一性原理方法计算出V-5Cr-5Ti合金的弹性常数、体模量、剪切模量、杨氏模量、泊松比和柯西压力等,并与计算出的纯钒的相关数值进行对比,结果表明V-5Cr-5Ti合金具有良好的塑性和强度,但其塑性要略低于纯钒的.并对加入氧原子后的V-5Cr-5Ti合金进行了相关计算,通过对比计算结果发现,由于氧原子的加入,使V-5Cr-5Ti合金的塑性和强度都出现了不同程度的降低.最后对V-5Cr-5Ti合金和纯钒的理论强度进行了计算,并绘制出两者的应力-应变关系图,通过对比再次验证了上面的结论.     

电感耦合等离子体原子发射光谱(ICP-AES)法测定Ti50Si合金中的钛元素

研究了ICP-AES测定Ti50Si合金中钛含量的方法。采用氢氟酸、硝酸溶解试样,优化了射频发生器(RF)功率、雾化压力、辅助气流量以及泵速等仪器参数,通过实验分析了溶液酸度、分析谱线的影响,确定了最佳实验条件。测定了2份Ti50Si样品,相对标准偏差小于0.64%(n=11),与硫酸高铁铵滴定法测定结果一致,证明了方法有较高的准确度和实用性。     

Ethene–propene copolymerization with the MgCl2-supported dichlorobis(4,4,4-trifluoro-1-phenyl- 1,3-butanedionato)titanium catalyst activated by an ordinary trialkylaluminum

The Ti(BFA)₂Cl₂/MgCl₂–Al(C₂H₅)₃ catalyst (BFA = 4,4,4-trifluoro-1-phenyl-1,3-butanedione) modified by DIPDMS (diisopropyldimethoxysilane), which had been proved to yield an extremely high isotactic polypropene in high selectivity, was tested for the copolymerization of ethene with propene. The analysis of resulting copolymers by CFC (cross fractionation chromatography) indicated the formation of a small quantity of ethene-rich copolymers as a byproduct, suggesting that the catalyst possesses not only Ti(III) species but a small portion of Ti(II) species. Whereas, the same catalyst without being modified by an external donor selectively yielded propene-rich random copolymers resulting from Ti(III) species in high yields. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2735–2740, 1998     

ChemInform Abstract: Determination of the Disordered Structure of Gd2Ba2CaCu2Ti3O14 with Multiple-Edge EXAFS and Powder Diffractograms.

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