Pr0.6-xNdxSr0.4FeO3-δ电极材料的光谱及性能研究

以柠檬酸-硝酸盐自蔓延燃烧法合成了ABO₃型钙钛矿结构的Pr_0.6-xNd_xSr_0.4FeO_3-δ(x=0.0～0.6)系列稀土复合氧化物粉体。利用傅立叶变换红外光谱(FTIR)和激光共焦拉曼光谱(LRS)对产物的晶体结构进行了表征。分别采用热膨胀仪测定烧结陶瓷体的热膨胀系数(TEC)；TG-DTA记录材料的热稳定性；XRD研究阴极材料与中温电解质Sm_0.2Ce_0.8O_1.9(SDC)及La_0.8Sr_0.2Ga_0.8Mg_0.2O_3-δ(LSGM)的化学相容性；SEM观察阴极/电解质复合材料的断口形貌。结果表明，该系列样品在高、低温热循环过程中化学稳定、晶型稳定；在室温至1 100 ℃范围内的平均热膨胀系数为1.16 × 10^-5 K^-1，与SDC及LSGM的热膨胀系数十分接近。阴极/电解质混合粉体1 200 ℃煅烧10 h，XRD未检测到新物质；SEM显示复合层断面界面清晰，没有相互扩散现象。该体系有望成为以SDC或LSGM为电解质的中温固体氧化物燃料电池合适的阴极材料。     

Copper(II)-catalyzed ether synthesis from aliphatic alcohols and potassium organotrifluoroborate salts

[reaction: see text] A protocol for the copper(II)-catalyzed etherification of aliphatic alcohols under mild and essentially neutral conditions is described. Air- and moisture-stable potassium alkenyl- and aryltrifluoroborate salts undergo cross-coupling with a variety of aliphatic primary and secondary alcohols and phenols, and are tolerant of a range of functional groups. The optimized conditions utilize catalytic copper(II) acetate with 4-(dimethylamino)pyridine as ligand in the presence of 4 A molecular sieves under an atmosphere of oxygen.     

氮杂冠醚研究Ⅶ、双仲胺型氮杂冠醚对过渡金属离子的选择性萃取作用

合成了五种新型双仲胺型氦杂冠醚，研究了它们对过渡金属离子进行液—液萃取，并用原子吸收法测定其浓度。实验结果表明：这类冠醚对Ａｇ￣＋、Ｐｄ￣（２＋）、和Ｐｔ￣（４＋）等贵金属离子有较强的选择配位性能，对选择性分离这些金属离子有重要的意义。     

硝酸钐水合物热分解过程的研究

Sm(NO_3)_3·6H_2O热分解过程的研究工作虽有文献报道,但结果不尽相同。文献[2]不同于文献[1,3],认为分解过程中存在无水盐阶段;文献[3]不同于文献[1,2],认为分解过程中存在低水合物。而且文献尚缺低水合物热分解机理的报道。我们也曾做过一些工作,但脱水阶段也不详尽。为此,我们详细地研究了Sm(NO_3)_3·nH_2O(n=     

多晶Hg0.09Cd0.91Te薄膜的光电化学行为

富镉Hg_(1-x)Cd_xTe是一种新型的光电转换材料,已用于固体结太阳能光伏电池:ITO/CdS/Hg_(1-)Cd_xTe/Au。我们曾对Hg_(1-x)Cd_xTe的电沉积机理作过研究。最近我们用电沉积制备的Hg_(0.09)Cd_(0.91)Te多晶薄膜做成了液体结太阳能光电化学电池并观察到明显光电响应。     

PTh / ZnO复合纳米粉的固相合成及其光谱特性

0引言导电聚合物/无机物纳米复合材料具有纳米材料和导电聚合物的共同特性,因此在电催化、二次充电电池材料、超级电容器材料等方面具有良好的应用前景[1]。聚噻吩(PTh)以及取代聚噻吩是导电聚合物领域中较早发现的具有环境稳定性和可加工性的材料之一。近年来,有关聚噻吩/无机物纳米复合材料的制备及其光电性能的研究倍受关注,Gebeyehu等[2]用PTh敏化纳米晶TiO2光伏电池,发现其光伏效率明显优于固态光伏电池;Jayant等[3]研究了PTh中的羧基基团的影响以及在纳米晶TiO2     

反相高效液相色谱法测定人血浆中曲尼司特浓度

 报道了用反相高效液相色谱法测定人血浆中曲尼司特浓度。以甲醇－磷酸二氢钾缓冲液（６０∶４０，Ｖ／Ｖ；ｐＨ４．２）为流动相，色谱柱采用ＹＷＧ－Ｃ１８不锈钢柱，紫外３３３ｎｍ波长检测，血浆样品经甲醇沉淀蛋白后直接进样测定。血浆浓度在０．６５～４０ｍｇ／Ｌ范围内线性良好，方法的平均回收率为１００．０％±４．１％。血浆最低检测浓度为０．２ｍｇ／Ｌ。对１０名健康志愿者口服２００ｍｇ曲尼司特后不同时间的血药浓度进行了测定。     

Photodynamic therapy based on organic small molecular fluorescent dyes

This review aims to provide a summary of the progress in organic small molecular fluorescent dyes for photodynamic therapy in recent years and it is classified according to the structures of dyes including cyanines, phthalocyanine, BODIPYs and other agents.     

Novel carboxylated oligothiophenes as sensitizers in photoelectric conversion systems

Novel carboxylated oligothiophenes with different thiophene units were designed and synthesized as photosensitizers in dye-sensitized solar cells (DSSCs) for efficient opto-electric materials. The introduction of -COOH into thiophene molecules can lead to a red shift of UV-visible absorption, increase light-harvesting efficiency, and enhance photoinduced charge transport by forming efficient covalent bonds to the substrate surface. A red shift of the absorption spectrum of oligothiophene is also achieved by the increase in the number of thiophene units. The DSSCs based on the oligomers have excellent photovoltaic performances. Under 100 mW cm(-2) irradiation a short-circuit current of 10.57 mA cm(-2) and an overall energy conversion efficiency of 3.36 % is achieved when pentathiophene dicarboxylated acid was used as a sensitizer. The incident photo-to-current conversion efficiency (IPCE) has a maximum as high as 80 %. In addition, photovoltage and photocurrent transients show that slow charge recombination in DSSCs is important for efficient charge separation and excellent photoelectric conversion properties of the oligomers. These initial and promising results suggest that carboxylated oligothiophenes are efficient photosensitizers.     

Detection of aniline at boron-doped diamond electrodes with cathodic stripping voltammetry

Boron-doped diamond (BDD) electrodes were used to investigate the possibility of detecting aniline by linear-sweep cathodic stripping voltammetry. It was found that the dimeric species (p-aminodiphenylamine and benzidine) formed by anodic oxidation of aniline during the accumulation period are involved in electrochemically reversible redox processes and, in acidic media, the shape of the stripping voltammetric response is suitable for aniline detection in the micromolar concentration range. The low background current of conductive diamond is an advantage compared to other electrode materials and allows a detection limit of 1 μM. Weak adsorption properties and the extreme electrochemical stability are additional advantages of BDD and it was found that, even after long-time measurements, the electrode surface can regain its initial activity by an anodic polarization in the potential region of water decomposition.