溶剂效应对聚苯撑乙烯掺杂二酰亚胺太阳电池性能的影响

研究了不同溶剂对2-甲氧基-5-(2-乙基己氧基)-1,4-对苯撑乙烯(MEH-PPV):N,N′-二(1-乙基丙基)-3,4,9,10-四羧酸二亚酰胺(EP-PTC)复合膜的形貌及其对以MEH-PPV:EP-PTC复合膜为活性层的太阳电池性能的影响.结果表明:非芳香性溶剂不利于MEH-PPV与EP-PTC的相容,MEH-PPV与EP-PTC两相间形成微米尺寸(0.5—5μm)的相分离,因而以MEH-PPV:EP-PTC复合膜为活性层的太阳电池中的电荷分离效率较低,进而电池的能量转换效率较低.而芳香性溶剂有利于MEH-PPV与EP-PTC的相容,MEH-PPV与EP-PTC两相间能形成纳米尺度的相分离,因此MEH-PPV与EP-PTC两相间的界面面积明显增加,界面处的电荷分离概率明显提高.与非芳香性溶剂相比,基于芳香性溶剂的复合膜太阳电池的能量转换效率提高了20倍.     

不同类型细胞穿膜肽二级结构特征研究

细胞穿膜肽是一类能以受体依赖或非受体依赖方式介导胞吞作用的小分子短肽,能够携带不同分子穿过细胞膜,这一特性使细胞穿膜肽成为一种有效的运输载体,为药物靶向治疗提供了新希望.本文从生物信息角度针对不同长度区间、运输不同类型分子细胞穿膜肽之间的异同二级结构特征进行了系统研究,同时进一步对不同穿膜方式对应的细胞穿膜肽二级结构特征进行了对比研究,结果表明不同类型细胞穿膜肽之间在二级结构组成上具有不同程度差异特征,为今后揭示细胞穿膜肽相关分子结构机制奠定可靠的理论基础.     

大气二氧化硫检测反应室的光学特性研究

为了适应检测大气中低浓度二氧化硫的需要,提出两个物理模型来定量分析反应室的横截面半径和内壁吸光率对反应室信噪特征的影响,计算结果表明存在一个最佳的半径,为反应室的优化设计提供理论依据。     

Antioxidant Activity of Ruthenium Cyclopentadienyl Complexes Bearing Succinimidato and Phthalimidato Ligands

In these studies, we investigated the antioxidant activity of three ruthenium cyclopentadienyl complexes bearing different imidato ligands: (η⁵-cyclopentadienyl)Ru(CO)₂-N-methoxysuccinimidato (1), (η⁵-cyclopentadienyl)Ru(CO)₂-N-ethoxysuccinimidato (2), and (η⁵-cyclopentadienyl)Ru(CO)₂-N-phthalimidato (3). We studied the effects of ruthenium complexes 1–3 at a low concentration of 50 µM on the viability and the cell cycle of peripheral blood mononuclear cells (PBMCs) and HL-60 leukemic cells exposed to oxidative stress induced by hydrogen peroxide (H₂O₂). Moreover, we examined the influence of these complexes on DNA oxidative damage, the level of reactive oxygen species (ROS), and superoxide dismutase (SOD) activity. We have observed that ruthenium complexes 1–3 increase the viability of both normal and cancer cells decreased by H₂O₂ and also alter the HL-60 cell cycle arrested by H₂O₂ in the sub-G1 phase. In addition, we have shown that ruthenium complexes reduce the levels of ROS and oxidative DNA damage in both cell types. They also restore SOD activity reduced by H₂O₂. Our results indicate that ruthenium complexes 1–3 bearing succinimidato and phthalimidato ligands have antioxidant activity without cytotoxic effect at low concentrations. For this reason, the ruthenium complexes studied by us should be considered interesting molecules with clinical potential that require further detailed research.     

Increase in the Intracellular Bulk Water Content in the Early Phase of Cell Death of Keratinocytes,Corneoptosis, as Revealed by 65 GHz Near-Field CMOS Dielectric Sensor

While bulk water and hydration water coexist in cells to support the expression of biological macromolecules, how the dynamics of water molecules, which have long been only a minor role in molecular biology research, relate to changes in cellular states such as cell death has hardly been explored so far due to the lack of evaluation techniques. In this study, we developed a high-precision measurement system that can discriminate bulk water content changes of ±0.02% (0.2 mg/cm³) with single-cell-level spatial resolution based on a near-field CMOS dielectric sensor operating at 65 GHz. We applied this system to evaluate the temporal changes in the bulk water content during the cell death process of keratinocytes, called corneoptosis, using isolated SG1 (first layer of stratum granulosum) cells in vitro. A significant irreversible increase in the bulk water content was observed approximately 1 h before membrane disruption during corneoptosis, which starts with cytoplasmic high Ca²⁺ signal. These findings suggest that the calcium flux may have a role in triggering the increase in the bulk water content in SG1 cells. Thus, our near-field CMOS dielectric sensor provides a valuable tool to dissect the involvement of water molecules in the various events that occur in the cell.     

Analysis of the generation mechanism of the S-shaped J—V curves of MoS2/Si-based solar cells

Amorphous-microcrystalline MoS$_{2}$ thin films are fabricated using the sol-gel method to produce MoS$_{2}$/Si-based solar cells. The generation mechanisms of the S-shaped current density-voltage ($J$-$V$) curves of the solar cells are analyzed. To improve the performance of the solar cells and address the problem of the S-shaped $J$-$V$ curve, a MoS$_{2}$ film and a p$^+$ layer are introduced into the front and back interfaces of the solar cell, respectively, which leads to the formation of a p-n junction between the p-Si and the MoS$_{2}$ film as well as ohmic contacts between the MoS$_{2}$ film and the ITO, improving the S-shaped $J$-$V$ curve. As a result of the high doping characteristics and the high work function of the p$^+$ layer, a high-low junction is formed between the p$^+$ and p layers along with ohmic contacts between the p$^+$ layer and the Ag electrode. Consequently, the S-shaped $J$-$V$ curve is eliminated, and a significantly higher current density is achieved at a high voltage. The device exhibits ideal p-n junction rectification characteristics and achieves a high power-conversion efficiency (CE) of 7.55%. The findings of this study may improve the application of MoS$_{2}$ thin films in silicon-based solar cells, which are expected to be widely used in various silicon-based electronic and optical devices.     

金刚石对顶砧原位电导率测量系统

 在金刚石对顶砧中进行原位高温高压电阻测量时,由于受到绝热层的限制,从而达不到理想的温度条件。采用普通的粉末绝热材料,会给电极的引入造成很大困难,而且不规则的电阻丝使电阻测量很难精确量化。利用溅射镀膜方法,在对顶砧的砧面上镀氧化铝膜作绝热层,溅射的金属钼膜作电极材料,成功地完成了高温高压条件下原位电阻的测量。利用此装置,测量了铁镁硅酸盐(Mg_0.875,Fe_0.125)₂SiO₄在高温高压环境下（31~35 GPa,1 500~3 400 K）的电导率,得到了样品的导电粒子激活能,发现其激活能随着压强的升高而增大,与低压低温（小于15 GPa,低于1 200 K）条件相比,其激活体积和激活能都明显减小。     

Wafer thickness optimization for silicon solar cells of heterogeneous material quality

In this Letter, we introduce a method of calculating the optimal wafer thickness for silicon solar cells with multicrystalline bulk material. The optimal thickness depends on the relation of bulk recombination to surface recombination and the light trapping. For multicrystalline silicon bulk recombination strongly varies laterally and with injection level, which complicates the calculations. A thickness optimization using the “Efficiency Limiting Bulk Recombination Analysis” (ELBA) takes all these effects correctly into account. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

空间微小碎片对低轨道航天器太阳电池表面撞击损伤研究

低轨道空间微小碎片密度相对较高,对太阳电池等大面积暴露材料的累积撞击损伤效应是航天器设计中应考虑的主要问题之一.以典型的太阳同步轨道为例分析和计算了太阳电池表面所遭遇的微小碎片通量,进行了微小碎片的撞击损伤模拟实验,并建立了撞击损伤方程.根据碎片通量分布及撞击损伤方程计算了微小碎片的超高速撞击所产生的太阳电池表面的面积损伤率,通过光学透射率的实验测试并结合理论模型,对碎片导致的太阳电池光学透射率衰减进行了计算和分析.结果表明,10a累积撞击导致的太阳电池表面的面积损伤率平均约为0.61%,严重时达到2.3 关键词： 微小碎片 超高速撞击 太阳电池 玻璃盖片     

Synthesis,structural characterization and in vitro cytotoxic activity of novel polymeric triorganotin(IV) complexes of urocanic acid

Two novel triorganotin carboxylate complexes of the biologically active urocanic acid have been synthesized and characterized. Elemental analysis, melting point, spectroscopic techniques – IR, ¹H, ¹³C and ¹¹⁹Sn NMR – mass spectrometry and X‐ray diffraction studies have been used for structural characterization. Crystal structures of the tin(IV) derivatives show that urocanic acid acts as a bridging bidentate ligand through its imidazole nitrogen atom and its carboxylic group, producing a polymeric one‐dimensional chain. The molecular structures of the complexes, catena‐poly‐tri(n‐butyl)tin(IV) 3‐(3H‐imidazol‐4‐yl)prop‐2‐enoate (1) and catena‐poly‐triphenyltin(IV) 3‐(3H‐imidazol‐4‐yl)prop‐2‐enoate (2), present a distorted trigonal–bipyramidal configuration. This is further confirmed by ¹¹⁹Sn NMR in the solid state. The tin(IV) derivatives form double‐stranded ribbons via N―H^…O―H bonds. Nevertheless, the compounds are essentially monomeric in solution, with a tetrahedral configuration as observed by ¹¹⁹Sn NMR in solution. The cytotoxic activity of the titled compounds has been tested against six human cell lines and the corresponding IC₅₀ values are reported. Both tin(IV) compounds have a high to very high in vitro cytotoxic activity against the tumor cell lines K562, HCT‐15 and MCF‐7. Compound 1 is 86 times more active than cisplatin in the HTC‐15 cell line. Copyright © 2012 John Wiley & Sons, Ltd.