Energy transfer mechanism of GdPO4: RE3+ (RE = Tb, Tm) under VUV-UV excitation

Polycrystal of GdPO₄:RE³⁺ (RE=Tb, Tm) phosphors were prepared by solid-state method. Vacuum ultraviolet excitation and emission spectrum and the energy transfer mechanism between the host and dopants of Tb³⁺ and Tm³⁺ were investigated respectively. The emission of Gd³⁺ at 313 nm was enhanced by the strong absorption of CTS of Tm³⁺ at 180 nm in GdPO₄: Tm. It has also been concluded that the excitation of Gd³⁺ is transferred to Tb³⁺ and then emission peaks of ⁵D_J→⁷F_J of Tb³⁺ were observed.     

1-吡啶-3-[4-(苯基偶氮)苯基]-三氮烯与汞的显色反应及其应用

在Triton X-100存在下的pH 10的Na2B4O7-NaOH缓冲介质中,研究了1-吡淀-3-[4-(苯基偶氮)苯基]-三氮烯(PYPAPT)与汞离子(Hg2 )的显色反应,建立了微量汞的测定方法。Hg2 与PYPAPT形成1∶2的红色络合物,络合物最大吸收波长位于518 nm,表观摩尔吸光系数为1.42×105L.mol-1.cm-1,Hg2 质量浓度在0~0.64 mg/L范围内符合比尔定律。方法用于铅锌矿样中微量汞的测定,RSD小于2.6%,测定结果与AAS法相符。     

氮化硅晶须的研究现状

介绍了晶须的生长机理、氮化硅晶须的制备方法以及影响其生长的因素。阐述了氮化硅晶须增强复合材料的现状,指出加强晶须的基础研究,改进制备技术和降低成本是今后的发展方向。     

Characterization of (Y,Gd) BxV1-xO4-x:Eu Phosphor Prepared by Coprecipitation Reaction

White body-color (Y, Gd)BxV1- xO4-x :Eu3 phosphors were prepared by coprecipitation reaction. Under VUV excitation at 147 nm, the red emission colorimetric purity of (Y, Gd)BxV1- xO4-x :Eu3 phosphor is much better than that of commercial PDP (plasma display panels) phosphor (Y, Gd)BO3:Eu3 . But its relative emission intensity is only about 90% of the commercial phosphor.     

Research on Poly （Styrene-Crylicacid）-Suported Neodymium Complex Catalytic Copolymerization of Styrene and 4-Vinylpyridine

Research on Poly(Styrene-Crylicacid)-Suported Neodymium Complex Catalytic Copolymerization of Styrene and 4-Vinylpyridine     

含3-三氟甲基的均三唑并[3,4-b]-1,3,4-噻二唑类化合物的合成

以 3-三氟甲基 - 4-氨基 - 5 -巯基 - 1 ,2 ,4-三唑为原料 ,分别与 2 - ,3- ,4-吡啶甲酸及α-萘乙酸在 POCl3催化下反应 ,制得 4种新的 3-三氟甲基 - 6-取代均三唑并 [3,4- b]- 1 ,3,4-噻二唑( 3a～ 3d) ,并利用 EA,IR,1H NMR等确定了其结构     

Zr-4合金板α相高温区轧制的织构演化

用(0002)正极图和织构取向因子等方法,研究了a相高温区沿原板材的轧向和横向轧制63%的Zr-4合金板的织构。实验结果表明:Zr-4合金板材在a相高温区轧制后的织构与原料板材的织构有关,这是由它的形变机制决定的。Zr-4合金板在a相高温区轧制时,{10`11}<`2113>和{11`21}<`2113> 锥面滑移是主要的形变系统,所以轧制后形成基极取向集中于轧面法向的织构。沿原始板材的轧向进行轧制时,部分晶粒中的{`1010}<`12`10>柱面滑移开动,使轧制后的ft大于fl;沿原始板材的横向进行轧制时,{11`21}<`1`126>孪生的作用使基极沿轧面法向上的取向增强。     

锆-4合金Masing特性的研究

为了更好地认识锆及其合金的循环变形行为及其机理，用单试样逐级加载法研究了锆-4合金在室温下的Masing特性。结果表明：锆—4合金是否出现Masing特性，取决于应变幅和材料状态。通过用Cottrell方法对滞后回线进行分析，得到了锆4合金具有Masing特性的充分必要条件：对于任何应变幅的循环变形，在某一固定的应变值，其对应的显微组织应该都是不变的。     

丙酸正丁酯绿色合成工艺中固体酸催化剂研制

针对目前酯化工艺过程中存在的环境污染问题,以丙酸正丁酯催化合成为例,对酯化过程清洁生产工艺中固体酸催化剂的制备进行了研究.制备了 SO_4~(2-)/TiO_2固体超强酸催化剂,讨论了各种制备条件对该催化剂的丙酸正丁酯合成催化活性的影响,采用 TG/DTA、FTIR、XRD 等仪器分析手段对催化剂结构进行了表征,实验结果表明,SO_4~(2-)/TiO_2固体超强酸催化剂具有很好的催化活性和选择性,且无腐蚀、反应时间短、后处理简单、重复使用性好.     

Facial motion cloning

We propose a method for automatically copying facial motion from one 3D face model to another, while preserving the compliance of the motion to the MPEG-4 Face and Body Animation (FBA) standard. Despite the enormous progress in the field of Facial Animation, producing a new animatable face from scratch is still a tremendous task for an artist. Although many methods exist to animate a face automatically based on procedural methods, these methods still need to be initialized by defining facial regions or similar, and they lack flexibility because the artist can only obtain the facial motion that a particular algorithm offers. Therefore a very common approach is interpolation between key facial expressions, usually called morph targets, containing either speech elements (visemes) or emotional expressions. Following the same approach, the MPEG-4 Facial Animation specification offers a method for interpolation of facial motion from key positions, called Facial Animation Tables, which are essentially morph targets corresponding to all possible motions specified in MPEG-4. The problem of this approach is that the artist needs to create a new set of morph targets for each new face model. In case of MPEG-4 there are 86 morph targets, which is a lot of work to create manually. Our method solves this problem by cloning the morph targets, i.e. by automatically copying the motion of vertices, as well as geometry transforms, from source face to target face while maintaining the regional correspondences and the correct scale of motion. It requires the user only to identify a subset of the MPEG-4 Feature Points in the source and target faces. The scale of the movement is normalized with respect to MPEG-4 normalization units (FAPUs), meaning that the MPEG-4 FBA compliance of the copied motion is preserved. Our method is therefore suitable not only for cloning of free facial expressions, but also of MPEG-4 compatible facial motion, in particular the Facial Animation Tables. We believe that Facial Motion Cloning offers dramatic time saving to artists producing morph targets for facial animation or MPEG-4 Facial Animation Tables.