基于大功率LED扩展光源的均匀光斑光辐射模拟器设计

基于边缘光线原理和光学扩展量守恒思想,结合复合抛物面聚光器和轴对称自由曲面透镜,设计并研制了大功率发光二极管扩展光源的反射/折射准直器.运用Tracepro软件对系统进行光束追迹模拟仿真和实验,研制出均匀光斑的光辐射模拟器.模拟器输出发散角为±12°光束,测量距离出射面50cm处光屏的光斑,在尺寸为14cm×14cm的光照范围内,测得光斑水平方向中心线上的光度均匀度优于4.1%,竖直方向中心线上的光度均匀度优于3.8%.     

用3-巯基丙酸修饰的CdTe量子点作为荧光探针对镉离子的荧光光度测定

对水热合成CdTe量子点的方法加以改进,并合成了用3-巯基丙酸(MPA)修饰的CdTe量子点(MPA-CdTe QD′s)。该量子点具有荧光特性,激发、发射波长分别为320,558nm。试验了17种常见金属离子对此量子点荧光强度的影响,结果发现只有Cd(Ⅱ)离子对其荧光有增强作用;Hg(Ⅱ)、Cu(Ⅱ)、Ag(Ⅰ)则对其荧光有猝灭作用,加入适量抗坏血酸和碘化钾可消除这3种金属离子的荧光猝灭作用。试验在pH 6的缓冲介质中,以20μL MPA-CdTe QD′s作为荧光探针,加入不同浓度的Cd(Ⅱ)离子并在反应6min后,体系的荧光增强程度与Cd(Ⅱ)离子浓度在5.0×10-7~3.9×10-5 mol·L-1范围内呈线性关系,检出限(3s/k)为4.8×10-7 mol·L-1。     

BiOI/Bi_2WO_6对甲基橙和苯酚的光催化降解及光催化机理(英文)

采用简单的沉积方法制备了不同碘化氧铋含量的BiOI/Bi2WO6光催化剂,通过X射线衍射(XRD)、扫描电子显微镜(SEM)、高分辨透射电子显微镜(HR-TEM)、紫外-可见漫反射光谱(UV-Vis DRS)和BET比表面积测量对其进行了表征。在紫外和可见光的照射下,使用甲基橙和苯酚的光催化降解评价了BiOI/Bi2WO6催化剂的光催化性能。结果表明:与商业P25和纯Bi2WO6相比,13.2%BiOI/Bi2WO6光催化剂具有更高的紫外和可见光催化性能。这明显增加的光催化活性主要归功于光生电子和空穴在Bi2WO6和BiOI界面上的有效转移,降低了电子-空穴对的复合。基于BiOI和Bi2WO6的能带结构,提出了光生载流子的一种转移过程。自由基清除剂的实验表明,·OH,h+,·O2-和H2O2,特别是h+,共同支配了甲基橙和苯酚的光催化降解过程。     

铂纳米粒子和锰卟啉修饰的聚苯胺新材料的制备及表征

借助循环伏安电化学聚合制备了聚苯胺(PANi)/MnT1239卟啉复合材料,再利用还原恒电位沉积法负载铂纳米粒子(Pt NP),最终制备了聚苯胺/MnT1239卟啉/铂纳米粒子复合材料.电沉积铂之后聚苯胺/MnT1239卟啉材料发生明显样貌变化,棒状结构平均直径从90 nm增加到200 nm,材料具有较大的表面积,空间可负载性好.铂纳米粒子平均尺寸在20 nm,附着均匀,氧化峰电流在0.2 V处达到7.4 mA,电化学性能优良.     

Syntheses,Structures, and Luminescent Properties of Two Zn~Ⅱ-organic Polymers Based on [Zn(ox)]_n Chains and Different Imidazole Linkers

Hydrothermal reactions of two imidazole derivatives(1,3,5-tib = 1,3,5-tris(1Himidazol-1-yl)benzene, 1,4-bimb = 1,4-bis(1H-imidazol-1-ylmethyl)benzene) and the ZnⅡ cations in the presence of oxalic acid(H2ox) afford two coordination polymers, namely, {[Zn(ox)(1,3,5-tib)]·2(H2O)}n(1) and [Zn1.5(ox)1.5(1,4-bimb)1.5]n(2). Their structures have been determined by single-crystal X-ray diffraction analyses, elemental analyses, IR spectra, and powder X-ray diffraction(PXRD) analyses. Both complexes 1 and 2 are based on the 1D zigzag [Zn(ox)]n chains, and their final structures are controlled by the two different imidazole linkers, which expanded the structure along different directions, finally giving a 3D dia net for 1 and a 2D sql layer for 2. Moreover, the luminescent properties of 1 and 2 have been investigated.     

Syntheses,Structures, and Properties of Three Coordination Polymers: [Cd_2(bpp)_(1.5)(Hbpp)(phen)_2]_n, [Mn_3(Htptc)_2(phen)_2(H_2O)_2]_n,and {[Cu(btc)_(0.5)(1,4-bib)]·2H_2O}_n

Hydrothermal reactions of three aromatic polycarboxylic acids and the transitional metal cations in the presence of phen and 1,4-bib afford three new coordination polymers: [Cd2(bpp)1.5(Hbpp)(phen)2]n(1), [Mn3(Htptc)2(phen)2(H2O)2]n(2), and {[Cu(btc)0.5(1,4- bib)]·2H2O}n(3)(H2bpp = 2,6-bis(4'-carboxyphenyl)-4-phenylpyridine, H4tptc = terphenyl-2,5,2',5'-tetracarboxylic acid, H4btc = biphenyl-2,2',4,4'-tetracarboxylic acid, phen = 1,10-phenanthroline, and 1,4-bib = 1,4-bis(1H-imidazol-1-yl)benzene). Their structures have been determined by singlecrystal X-ray diffraction analyses, elemental analyses, IR spectra, and powder X-ray diffraction(PXRD) analyses. In compound 1, the CdII cations are linked by bpp2- to form one ladder structure, based on which a 3D network is constructed with the help of non-covalent interactions. The topology of 2 is a 3D(3,4,5)-connected framework with the Point Schl?fli symbol of(42.6)32(4.62.8)(45.64.8)2. Compound 3 shows an unprecedented 3D(4,4)-connected framework with the Point Schl?fli symbol of(64.82)2(65.8). Moreover, the luminescent property of 1 has been investigated.     

苏丹红猝灭吖啶染料荧光的动力学研究

在体积分数95%乙醇介质中,吖啶黄、吖啶橙的荧光发射波长与苏丹红染料的吸收波长十分接近。实验数据表明,随着苏丹红I~IV用量的增加,溶液中吖啶黄、吖啶橙荧光发射强度明显降低,其荧光猝灭程度与苏丹红用量成正比。动力学研究表明苏丹红I,II与吖啶黄或吖啶橙之间可形成非共价复合物,从而发生静态荧光猝灭;而苏丹红III,IV猝灭吖啶黄或吖啶橙则表现为一种复杂的动力学特点,可能同时存在静态荧光猝灭与动态猝灭。     

分级纳米材料的结构、制备及其应用

纳米材料因其独特的表面效应、体积效应和量子效应等特点,在化工、生物工程、医学和能源等领域有着广阔的应用。 由简单的低维纳米结构作为主要的构建单元并按照特定的排列方式组装成规整有序的三维结构,即分级纳米结构,已经开展了许多的研究。 本文综述了分级纳米结构的制备方法和微观结构,及其在污水处理、超级电容器、太阳能电池以及光催化等领域的应用。     

Synthesis and Electronic Structure of Triazasubporphyrin with Peripherally Low Symmetric Push-pull Substitutions

Peripherally low symmetric substitution with electron-donating(EDG)and electron-withdrawing(EWG)substituents caused the rational modulation of geometric structure and even the electronic structure of triazasubporphyrin,the smallest 14πconjugated aza-porphyrinoids.Both structural characterization and spectroscopic investigation were discussed to provide an in-depth understanding of the relationship between peripheral push-pull substituents and SubPz core.     

Crystal Structure of Scheelite-type LiTb(WO_4)_2 and Multi-color Emitting Properties Doped by Eu~(3+)

Single crystal of lithium terbium tungstate LiTb(WO4)2 has been grown by the flux method. The crystal structure was refined from single-crystal X-ray data. It crystallizes in tetragonal system, space group I41/a with a = 5.1749(9), c = 11.1953(19) ?, V = 299.81(12) ?~3, Z = 2, Mr = 661.56, Dc = 7.328 g/cm^3, F(000) = 560, μ(MoKα) = 49.94 mm^-1, R(F^2 > 2σ(F^2)) = 0.026 and wR(F^2) = 0.070. It features a typical scheelite-type structure composed of two-direction packing of isolated WO4 tetrahedra. Li and Tb atoms in the structure occupy the same crystallographic site. Moreover, a series of solid solution phosphors LiTb(1-x)Eux(WO4)2(x = 0.004~0.1) were synthesized by high temperature solid-state reactions. The phosphors could be effectively excited by a wavelength range from 379 to 487 nm, which matches well with the UV and near-UV LED chip. The emission color of the phosphor can be tuned from green, through yellow to red by simply adjusting the relative Eu³⁺ and Tb³⁺ concentration due to the Tb³⁺ to Eu³⁺ energy transfer.