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71.
72.
Clicked Isoreticular Metal–Organic Frameworks and Their High Performance in the Selective Capture and Separation of Large Organic Molecules 下载免费PDF全文
Chung Yen Ang Hongzhong Chen Dr. Jia Liu Prof. Dr. Ruqiang Zou Prof. Dr. Yanli Zhao 《Angewandte Chemie (International ed. in English)》2015,54(43):12748-12752
Three highly porous metal–organic frameworks (MOFs) with a uniform rht‐type topological network but hierarchical pores were successfully constructed by the assembly of triazole‐containing dendritic hexacarboxylate ligands with ZnII ions. These transparent MOF crystals present gradually increasing pore sizes upon extension of the length of the organic backbone, as clearly identified by structural analysis and gas‐adsorption experiments. The inherent accessibility of the pores to large molecules endows these materials with unique properties for the uptake of large guest molecules. The visible selective adsorption of dye molecules makes these MOFs highly promising porous materials for pore‐size‐dependent large‐molecule capture and separation. 相似文献
73.
Efficient Counter Electrode Manufactured from Ag2S Nanocrystal Ink for Dye‐Sensitized Solar Cells 下载免费PDF全文
Qingquan He Shoushuang Huang Dr. Jiantao Zai Nianqi Tang Bo Li Prof. Qiquan Qiao Prof. Xuefeng Qian 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(43):15153-15157
It is generally believed that silver or silver‐based compounds are not suitable counter electrode (CE) materials for dye‐sensitized solar cells (DSSCs) due to the corrosion of the I?/I3? redox couple in electrolytes. However, Ag2S has potential applications in DSSCs for catalyzing I3? reduction reactions because of its high carrier concentration and tiny solubility product constant. In the present work, CE manufactured from Ag2S nanocrystals ink exhibited efficient electrocatalytic activity in the reduction of I3? to I? in DSSCs. The DSSC consisting of Ag2S CE displayed a higher power conversion efficiency of 8.40 % than that of Pt CE (8.11 %). Moreover, the devices also showed the characteristics of fast activity onset, high multiple start/stop capability and good irradiated stability. The simple composition, easy preparation, stable chemical property, and good catalytic performance make the developed Ag2S CE as a promising alternative to Pt CE in DSSCs. 相似文献
74.
Dye‐sensitized solar cells (DSSCs) have received significant attention from the scientific community since their discovery in 1991. However, the high cost and scarcity of platinum has motivated researchers to seek other suitable materials for the counter electrode of DSSCs. Owing to their exceptional properties such as high conductivity, good electrochemical activity, and low cost, carbon nanotubes (CNTs) have been considered as promising alternatives to expensive platinum (Pt) in the counter electrode of DSSCs. Herein, we provide a Minireview of the CNTs use in the counter electrode of DSSCs. A brief overview of Pt‐based counter electrodes is also discussed. Particular attention is given to the recent advances of counter electrodes with CNT‐based composite structures. 相似文献
75.
76.
The application of near-infrared (NIR) dyes (λ
em > 750 nm) to the analysis of biological samples shows much promise, because the long emission wavelengths of such dyes allow
interferences from biomolecule matrices to be minimized. In this paper, a novel NIR dye, 5,5′-dicarboxy-1,1′-disulfobutyl-3,3,3′,3′-tetramethylindotricarbocyanine
(DCDSTCY) has been developed for the spectrophotometric determination of total protein in serum. Under acidic conditions,
the binding of DCDSTCY to proteins caused a new peak at 878 nm, the height of which was proportional to the concentration
of protein. The linear range of the method was found to be 0.04–0.5 μg mL−1 for bovine serum albumin (BSA) and human serum albumin (HSA), and detection limits of 5 ng mL−1 were obtained for these substances. The maximum binding number of BSA with DCDSTCY was measured to be 133. The method proposed
here has been applied to the quantitation of total protein in serum, and recoveries of 96.6–104% were achieved.
Figure Near-infrared probe for protein determination 相似文献
77.
78.
A. A. Ishchenko 《Russian Chemical Bulletin》1994,43(7):1161-1174
The general characteristics that relate the length of the polymethine chain of symmetrical cyanine dyes to their spectral-luminescent properties depending on the electron-donor character of the heterocycles and the nature of the solvent are formulated. For various types of symmetrical cyanines, the Stokes shifts decrease with the elongation of the polymethine chain due to weakening of the vibronic interactions. The vinylene shifts of the band maxima are essentially constant and fall within the range 100 to 130 nm depending on the nature of the heterocycles and the solvent. When the polymethine chain elongates the fluorescence quantum yields first increase and then decrease. The greater the effective length of the heterocycle the stronger the decrease. The fluorescence decay occurring when the polymethine chain gets longer is associated with intensification of the internal conversion. For symmetrical cyanines, the changes in the shapes of the electronic bands (their width, asymmetry, excess, and fine structure) as the chain elongates are governed by the competing effects of the vibronic and intermolecular interactions. The former decrease as the chain lengthens, causing the narrowing of the absorption bands for the lower vinylogs. On the other hand, the latter increase as chain lengthens, which leads to broadening of the bands for the higher vinylogs. The higher the solvent nucleophilicity and the greater the deviation of the electron-donor ability of the heterocycle from the average value the greater the broadening. Any elongation of the polymethine chain of symmetrical cyanines causes only narrowing of the bands and an increase in the asymmetry, excess, and structuring in the fluorescence spectra, which, unlike the absorption spectra, is independent of the electron-donor character of the heterocycles and the nature of the solvent. These effects are caused by the fact that, in contrast to absorption, changes in the shape of emission bands with increasing chain length are governed predominantly by vibronic rather than by intermolecular interactions.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1227–1239, July, 1994. 相似文献
79.
以硝酸银、钛酸四丁酯、无水氯化锌、六水氯化铁为原料,采用溶胶-凝胶法与溶剂热相结合的方法制备了ZnFe2O4/Ag/TiO2复合材料,通过扫描电子显微镜、能谱分析仪、X射线粉末衍射仪、X射线光电子能谱仪、振动样品磁强计、紫外可见分光光度计对样品进行表征及测试。结果表明:ZnFe2O4/Ag/TiO2-10具有最佳的光催化效果,在紫外和可见光下对染料的降解率都能达到90%以上,具有优异的紫外可见光光催化活性。ZnFe2O4/Ag/TiO2具有独特的磁性,能在外部磁场作用下进行回收利用,这使其在实际应用中成为可能。通过磁分离技术重复回收利用5次后仍然保持优良的光催化性能,说明ZnFe2O4/Ag/TiO2-10具有优异的磁性及较高的光催化循环稳定性。 相似文献
80.
Textile and dye industries are main sources of dye bearing effluent. In present studies the anaerobic biological degradation of Acid Red 3BN dye water (AR3BNDW) and mixed dye water (MDW) for reduction of color and COD were studied in sequential batch reactor (SBR). The sludge as sources of microorganism was arranged from maize processing bio methanation wastewater treatment plant, which was acclimatized for treatment of AR3BNDW and MDW. After the acclimatization, dyes degradation were studied in SBR At optimum operation condition of hydraulics retention time (HRT) = 2.5 d, and treatment time (tR) = 16 h, AR3BNDW have gone maximum 87% color reduction of 500 mg/L dye, and 82.8% COD reduction of 380 mg/L COD. At same operating condition, 84.5% color reduction of 500 mg/L dye, and 79.42% COD reduction of 413 mg/L COD achieved for MDW. The second order Grau model was fitted well for COD and dye reductions. The kinetics parameter were evaluated for both the dye water. 相似文献