Sonochemical synthesis of CH3NH3PbI3 perovskite ultrafine nanocrystal sensitizers for solar energy applications

The organic–inorganic hybrid perovskite CH₃NH₃PbI₃ is becoming an interesting material in the field of energy harvesting. This material is one of the cleanest and cheapest components in solar cells which is available in ample amounts. However, most of the previous research work was done on thin film of this material. In the present work we describe the preparation of a powder containing nanoparticles of CH₃NH₃PbI₃ using a sonochemical method. Characterization of the product was done by various methods, such as HRTEM, FTIR, PL, DLS and XRD. The particles were found to be highly crystalline (tetragonal crystal structure), polygonal in shape and having diameters of 10–40 nm.     

稀土有机光→电、电→光转换器件

198 6年Ｔａｎｇ发表双层有机光伏电池[1] 与无机光伏电池相比 ,以重量轻 ,材料经济并可以沉积在柔性衬底上等潜在优势正在引起人们注意。目前对有机光伏效应的研究多集中在聚苯乙炔 (ＰＰＶ)及其衍生物上[2 ,3 ] ,能量转换效率在 10ｍＷ·ｃｍ- 2 紫外光照下可超过 4 % [4 ] ;以小分子有机物制成的光伏器件也得到研究人员的关注[5,6] 。但是采用稀土配合物作为电子给体层的有机光伏器件还未见报道。我们研究组一直对以稀土有机配合物为发光层的有机ＥＬ器件进行研究[7,8] 。在研究ＥＬ器件特性过程中 ,我们发现稀土有机电致发光器件在紫外…     

牛天然纤溶酶原Kringles结构域片段的获得及其抑制内皮细胞增殖作用研究

利用猪胰弹性蛋白酶和尿激酶限制性酶切牛纤溶酶原,获得了纤溶酶原Kringles结构域片段Kringles1-3(K1-3)和Kingles1-4(K1-4),研究发现,在没有自由巯基供体存在的条件下,尿激酶酶发牛纤溶酶原也能够产生K1－4,从而认为存在由尿激酶酶切牛纤溶酶原直接产生K1－4的途径,所获得的K1－3和K1－4对恒河猴脉络膜－视网膜RF／6A血管内皮细胞的增殖有抑制活性。     

TNFa在血管内皮细胞ECV304中的靶向表达研究

在缺失了3'LTR U3区内病毒的启动子／增强子序列的逆转录病毒载体pLXSNd中,用血管内皮生长因子受体KDR的特异性启动子调控了TNFa在血管内细胞ECV304中的靶向表达。将构建的载体pLXSN-TNFa,pLXSNd-KDRp-TNFa和空载体pLXSN用PA317细胞包装后获得重组病毒,并用重组病毒分别感染NIH3T3细胞和ECV304细胞,培养物上清的ELISA结果证明,KDR启动子指导的TNFa在KDR阳性细胞ECV304中的表达量为在KDR阴性细胞NIH3T3中的表达量的8倍;而TR指导的TNFa在这两种细胞中的表达无明显差异,实现了TNFa在血管内皮细胞中的靶向表达,这可能为肿瘤基因治疗提供新途径。     

The effects of alternative stress on the cell membrane deformability of chrysanthemum callus cells

The effects of alternative stress, which was generated through a strong sound field apparatus set up in our lab, on cultured chrysanthemum callus cells were studied. Meanwhile we measured the deformability of chrysanthemum cell membranes and studied the influence of the cytoskeleton after the treatment of colchicine using micropipette aspiration technique. Based on our experimental results, we found that the deformability of cell membrane decreased in stress condition. However, the effect disappeared after the treatment of cytochalasin. Therefore, we thought that the reason on the deformability of cells decreasing was the microfilament rearranging and consequently the cells becoming more rigid under the alternative stress.     

液滴光池的荧光光化学传感器研究

基于荧光熄灭原理 ,自制一种液滴传感装置 ,采用蠕动泵自动进液 ,定时微机控制处理。试验发现 3,3′ ,5 ,5′ 四甲基联苯胺二盐酸盐 (TMB d)具有非常强的荧光 ,其荧光信号在不同的条件下能被过氧化氢熄灭 ,而且荧光信号的强度与样品浓度在一定范围内呈线性关系。选取最佳的试验条件 ,测得过氧化氢的线性响应范围为 3.2 2× 10 - 7～ 3.33× 10 - 4mol·L- 1,检出限为 3 3× 10 - 10 mol·L- 1。利用日立 85 0型荧光分光光度仪作静态分析比较 ,可得相似的响应现象     

微柱分离中的激光诱导荧光检测

 激光诱导荧光检测 (LIFD)以其高的灵敏度和选择性而被广泛应用于微柱分离技术中。以检测池为轴线 ,概述了激光诱导荧光检测系统新进展及其应用。引用了 5 2篇文献     

1,5-二(2-羟基苯亚甲基)-二氨基硫脲与银配合物的合成、表征及抗癌活性研究

近年来,由于缩氨基硫脲类过渡金属配合物具有较高的抗癌、抗菌活性,受到化学界和药学界研究人员的广泛重视。实验证明不同缩氨基硫脲与不同过渡金属形成的配合物其抗癌活性不同。1,5－二（2－羟基苯亚甲基）－二氨基硫脲是一种水杨醛缩氨基硫脲类衍生物,而有关其银配合物的合成及抗肿瘤方面的研究目前尚未见报道。鉴于此,我们在以前工作的基础上合成了标题化合物,通过元素分析、红外光谱、紫外光谱、核磁共振氢谱、摩尔电导和溶解性等测试,对配合物进行了表征。同时测定了配体和配合物的抗肿瘤活性,旨在为开发新的抗肿瘤药物提供理论依据。     

Study on photoconductivity of dye-polymer-based solid-state thin film

In this article, we describe a solid-state photoelectrochemical cell for light detection. Safranine-T dye mixed with polyvinyl alcohol (PVA) solution was deposited on a conducting and transparent indium-tin-oxide (ITO)-coated glass that was used as one electrode and another ITO-coated glass as the counterelectrode. A solid polymeric electrolyte consisting of polyethylene oxide-ammonium perchlorate-ethylene carbonate and propylene carbonate with suitable weight ratio was prepared and sandwiched between these two ITO-coated glass electrodes, which were separated by a Teflon spacer about 50 μm thick. The cell was biased with a direct current source to make the dye and PVA-coated ITO as the anode and the other ITO as the cathode. On illumination by a tungsten lamp, from the cathode side, the change of photocurrent was measured. The dark current-voltage characteristics and the growth and decay of the photocurrent for steady and pulsed illumination were studied.     

Physical and morphological characteristics and electrochemical behaviour in PEM fuel cells of PtRu /C catalysts

Platinum-ruthenium catalysts supported on carbon (PtRu/C) have been characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), specific surface area analysis (BET), X-ray photoelectron spectroscopy (XPS) and in proton exchange membrane (PEM) fuel cell tests. The results indicate the presence of strong metal-carbon interactions, which hinder the formation of a single-phase face-centered cubic (fcc) PtRu alloy. The particle size of the PtRu/C catalysts was smaller than both carbon-supported platinum (Pt/C) and ruthenium (Ru/C) catalysts. In the bimetallic electrocatalysts the intercrystallite distance decreased with respect to pure Pt and Ru metals. PEM fuel cell tests in H₂/air operation mode revealed a decrease of performance with increasing carbon content of the catalyst, at a fixed Pt loading. In H₂ + 100 ppm CO/air operation mode the maximum performance of the PEM fuel cell was attained at 0.63 atomic fraction Ru. Received: 2 December 1999 / Accepted: 27 January 2000