Solution-based synthesis of quaternary Cu-In-Zn-S nanobelts with tunable composition and band gap

We have demonstrated that quaternary Cu(x)In(x)Zn(2(1-x))S(2) nanobelts could be synthesized through a facile solution-based method. The composition and band gap of quaternary nanobelts can be tuned within the broad range by changing the relative ratio of precursors. The growth mechanism of quaternary nanobelts was deduced to be catalyst-assisted growth.     

New hydroxylated metabolites of 4-monochlorobiphenyl in whole poplar plants

Background

The importance of the isatinic quinolyl hydrazones arises from incorporating the quinoline ring with the indole ring. Quinoline ring has therapeutic and biological activities whereas, the indole ring occurs in Jasmine flowers and Orange blossoms. As a ligand, the isatin moiety is potentially ambidentate and can coordinate the metal ions either through its lactam or lactim forms. In a previous study, the ligational behavior of a phenolic quinolyl hydrazone towards copper(II)- ions has been studied. As continuation of our interest, the present study is planned to check the ligational behavior of an isatinic quinolyl hydrazone.

Results

New homo- and heteroleptic copper(II)- complexes were obtained from the reaction of an isatinic quinolyl hydrazone (HL) with several copper(II)- salts viz. Clˉ, Brˉ, NO₃ˉ, ClO₄ ^-, SO₄ ^2- and AcO^-. The obtained complexes have O_h, T_d and D_4h- symmetry and fulfill the strong coordinating ability of Clˉ, Brˉ, NO₃ˉ and SO₄ ^2- anions. Depending on the type of the anion, the ligand coordinates the copper(II)- ions either through its lactam (NO₃ˉ and ClO₄ ^-) or lactim (the others) forms.

Conclusion

The effect of anion for the same metal ion is obvious from either the geometry of the isolated complexes (O_h, T_d and D_4h) or the various modes of bonding. Also, the obtained complexes fulfill the strong coordinating ability of Clˉ, Brˉ, NO₃ˉ and SO₄ ^2- anions in consistency with the donor ability of the anions. In case of copper(II)- acetate, a unique homoleptic complex (5) was obtained in which the AcO^- anion acts as a base enough to quantitatively deprotonate the hydrazone. The isatinic hydrazone uses its lactim form in most complexes.     

Zeolite synthesis from waste fly ash and its application in CO<Subscript>2</Subscript> capture from flue gas streams

Zeolite A and A + X mixtures were prepared from coal-fly ash procured from China by using an alkali fusion method. X-ray diffraction showed that both the materials were crystalline and reproducible. Scanning Microscopy revealed that pure zeolite A particles have cubic morphology while the mixture shows intergrowth of cubic and pyramidal crystals. The surface area for A + X mixture was around 330 m²/g which is higher than zeolite A, however, lower than typical X zeolite. CO₂ and N₂ adsorption isotherms were measured and the data was fitted by the Dual Site Langmuir equation. These zeolites were then tested for CO₂ capture at different temperatures in a process with a nine step cycle. When compared with 13X zeolites at higher temperature (∼90 °C), both the zeolite A + X mixture and zeolite A prepared from fly ash showed better performance in CO₂ capture from flue gas because they have higher selectivity of CO₂ over N₂.     

Hydrothermal synthesis of Na(0.5)La(0.5)TiO3-LaCrO3 solid-solution single-crystal nanocubes for visible-light-driven photocatalytic H2 evolution

Cubic perovskite structure photocatalysts of Na(0.5)La(0.5)TiO(3) and (Na(0.5)La(0.5)TiO(3))(1.00)(LaCrO(3))(0.08) solid solution that consisted of well-defined single-crystal nanocubes were successfully prepared by means of facile and surfactant-free hydrothermal reactions for the first time. The results from different instrumental characterizations and theoretical calculations consistently confirmed the formation of nanocubic single-crystal solid solution of (Na(0.5)La(0.5)TiO(3))(1.00)(LaCrO(3))(0.08), and clearly revealed the modification of its physicochemical properties compared with those of Na(0.5)La(0.5)TiO(3). In particular, the effective narrowing of the bandgap (from 3.19 to 2.25 eV) by Cr(3+) in the solid solution made it possible to utilize visible light. The solid-solution configuration maintained the charge balance to preserve the valence of Cr(3+) rather than Cr(6+), and accommodated Cr(3+) with high content to form new energy bands instead of localized impurity levels. The hydrothermal preparation strategy ensured the formation of single crystals with high purity, few defects, and regulated morphology; it also guaranteed the valences of Ti(4+) and Cr(3+) in the solid solution. Consequently, the recombination of photogenerated carriers could be effectively suppressed to benefit photocatalytic H(2) evolution. (Na(0.5)La(0.5)TiO(3))(1.00)(LaCrO(3))(0.08) nanocubic single-crystal solid solution showed stable photocatalytic activity, and thus was proved to be a promising candidate for visible-light-driven photocatalytic H(2) evolution.     

镧、铒共掺杂压敏漆的制备及荧光特性

以联吡啶,氯化钌,氯化镧,氯化铒为原料合成了镧、铒共掺杂的探针分子.将探针分子加入到硅溶胶基质中获得了镧、铒共掺杂的压敏漆样品.采用IR,SEM,XPS及荧光发射光谱对探针分子和压敏漆进行了测试分析.红外光谱测试结果表明,探针分子中联吡啶的结构没有被破坏.扫描电镜观察发现探针分子呈花瓣状,XPS测试发现压敏漆中含有Er,La,Ru等元素,说明稀土元素确实被掺入到压敏漆中.紫外吸收光谱表明压敏漆的最佳吸收波段位于200 ～ 500 nm处,选择410 nm作为激发光源,压敏漆在590 nm处有很强的荧光发射,并且随着空气压力的增大即氧分子浓度的增加,压敏漆的荧光强度降低,说明压敏漆具有较好的氧猝灭特性.     

镓离子配合物印迹聚合物的研制及吸附性能研究

以8-羟基喹啉镓(Gaq3)为模板分子,丙烯酰胺为功能单体,二甲基丙烯酸乙二醇酯为交联剂,偶氮二异丁腈为引发剂,由沉淀聚合法在三氯甲烷和甲醇(体积比3:2)的混合溶剂中制备镓离子印迹聚合物.采用红外光谱和热重分析对其进行表征;采用等温平衡吸附实验和Langmuir吸附模型分析研究其吸附性能.以其作为固相萃取填料,应用于...     

气相色谱/负化学电离源质谱法测定底泥中的有机氯农药

建立了气相色谱/负化学电离源质谱(GC-NCI-MS)法测定底泥中24种有机氯农药(OCPs)残留的方法.样品采用索氏提取、硅胶/氧化铝复合柱分离纯化,p,p'DDT、o,p'-DDT采用外标法定量,其余的有机氯农药均采用内标法定量.同时,对气相色谱/负化学电离源质谱(GC-NCI-MS)法与气相色谱/电子轰击离子源质...     

YVO4:Eu荧光纳米粒子的制备及其测定孔雀石绿的研究

以聚丙烯酸为修饰剂,采用水热法合成YVO4:Eu荧光纳米粒子.实验考察了聚丙烯酸加入量、溶液pH值、反应温度等条件对粒子荧光性能的影响.在优化的条件下,合成粒子的荧光强度大,水溶性良好、溶液均匀稳定.对合成粒子进行了表征,红外光谱实验表明,粒子表面包覆了聚丙烯酸;XRD实验表明,制备了单一相YVO4晶体;TEM测试表明合成粒子分散性较好,粒度均匀,粒径在25nm左右.以合成稀土粒子为能量供体,孔雀石绿为能量受体,建立了荧光共振能量转移体系.基于以上体系,实现了对孔雀石绿的定量检测.方法的线性范围为5.00×10-5～5.00×10-3g·L-1,检出限为2.0×10-5 g·L-1.     

CRAFT TF Dummy 线圈 VPI 模具设计与分析

环向场(Toroidal Field, TF) 线圈是聚变堆主机关键系统综合研究设施(CRAFT) 的重要组成部分, 由CICC(Cable in Conduit Conductor) 导体完成线圈绕制, 通过真空压力浸渍(Vacuum Pressure Impregnation, VPI)完成线圈绝缘处理. 在树脂浸渍线圈绝缘层, 随后进行较长时间的高温固化, 以完全固化整个绝缘层的树脂. 在浸渍和固化过程中,VPI 模具不仅承受线圈本身的载荷, 还要承受大气压力、 内部打压、 热变形等. 为了保证线圈绝缘质量, 采用 CATIA 软件对 VPI 模具进行3D 建模, 并对 VPI 模具进行了 Ansys Workbench 有限元软件分析与校核. 分析表明,VPI 模具的设计合理, 为工程设计提供了理论和实践依据.