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71.
Min-Woo Lee Jae-Yup Kim Hyung-Geun Lee Hyun Gil Cha Duck-Hyung Lee Min Jae Ko 《Journal of Energy Chemistry》2021,(3):208-216
Herein,we examine the performance of dye-sensitized solar cells containing five D-π-A organic dyes designed by systematic modification of π-bridge size and geometric structure.Each dye has a simple push-pull structure with a triarylamino group as an electron donor,bithiophene-4,4-dimethyl-4 H-cyclopenta 1,2-b:5,4-b’]dithiophene(M11),4,4-dimethyl-4 H-cyclopenta[1,2-b:5,4-b’]dithiophenethiophene(M12),thiophene-4,4-dimethyl-4 H-cyclopenta[1,2-b:5,4-b’]dithiophene(M13),4,4-dimethyl-4 H-cyclopenta[1,2-b:5,4-b’]dithiophene-benzene(M14),and 4,4-dimethyl-4 H-cyclopenta[1,2-b:5,4-b’]dithiophene(M15)units asπ-bridges,and cyanoacrylic acid as an electron acceptor/anchor.The extension of theπ-bridge linkage favors wide-range absorption but,because of the concomitant molecular volume increase,hinders the efficient adsorption of dyes on the TiO2 film surface.Hence,higher loadings are achieved for smaller dye molecules,resulting in(i)a shift of the TiO2 conduction band edge to more negative values,(ii)a greater photocurrent,and(iii)suppressed charge recombination between the photoanode and the redox couple in the electrolyte.Consequently,under one-sun equivalent illumination(AM 1.5 G,100 mW/cm2),the highest photovoltage,photocurrent,and conversion efficiency(η=7.19%)are observed for M15,which has the smallest molecular volume among M series dyes. 相似文献
72.
Frontispiece: In Vivo Residue‐Specific Dopa‐Incorporated Engineered Mussel Bioglue with Enhanced Adhesion and Water Resistance 下载免费PDF全文
73.
YS Kim A Cha JY Shin HJ Jeon JH Shim C Lee SG Lee 《Chemical communications (Cambridge, England)》2012,48(71):8940-8942
Gold nanoparticles (AuNPs) were assembled with high density onto multi-walled carbon nanotubes, which were functionalized with zwitterionic poly(imidazoliumsulfonate). The AuNP/zwitterionic CNT hybrids exhibited decent electrocatalytic activity in oxygen reduction reaction as the AuNP-based catalysts. 相似文献
74.
Kim N Kim W Lee S Lee H Rhee H Choi Y Jung Y Cha S 《Experimental & molecular medicine》1999,31(4):185-190
Clinical cases of type-1 hypersensitive reaction to rice (Oryza sativa) have been reported in western countries as well as in Japan. Among rice proteins, 14-16 kD globulin proteins encoded by multiple gene family have been identified as major rice allergens. In this study, a rice cDNA library was constructed using lambda UniZap vector and screened with a rat anti-16 kD globulin protein polyclonal antibody in order to isolate Korean rice allergenic cDNA clones. Five independent cDNA clones, termed RAK1-5, were obtained after second rounds of plaque assay and immunoblot analysis. These clones encoded 13-19 kD recombinant proteins upon IPTG induction, which were identified by the polyclonal antibody in immunoblot analysis. DNA sequencing analysis showed that RAK1-4 have 99% sequence homology with RA5b, and RAK5 is closely related with RA14c. This result indicated that RA5b gene is widely distributed in our cDNA library among other possible rice allergenic genes, and more study is needed to isolate heterogeneous or novel rice allergen genes. 相似文献
75.
Carbonate-selective membranes were prepared by incorporating a molecular tweezer-type carbonate-selective neutral carrier [N,N-dioctyl-3alpha,12alpha-bis(4-trifluoroacetylbenzyloxy)-5beta-cholan-24-amide] into a room temperature vulcanizing-type silicone rubber (3140 RTV-SR) matrix, and deposited on the planar-type electrodes (Pt containing Ag/AgCl electrodes formed on a ceramic plate) with and without an intermediary conducting polymer layer. Two types of solvent-soluble conducting polymers [poly(1-hexyl-3,4-dimethyl-2,5-pyrrolylene) or poly(3-octylthiophene-2,5-diyl)] have been examined as the solid contact material. Potentiometric properties of the resultant all-solid-state electrodes were evaluated in terms of their carbonate selectivity, response slope, potential stability and reproducibility. The sensitivity and carbonate selectivity of the SR membrane-based all-solid-state electrodes with conducting polymer solid contact were comparable to those of conventional electrodes. Experimental results also showed that the intermediary conducting polymer layer used in the all-solid-state electrodes greatly reduces the interference from dissolved oxygen. 相似文献
76.
This work reports a numerical study undertaken to investigate the dynamic response of a rotor supported by two turbulent flow
model journal bearings with nonlinear suspension and lubricated with couple stress fluid under quadratic damping. This may
be the first time that analysis of rotor-bearing system considered the quadratic damping effect. The dynamic response of the
rotor center and bearing center are studied. The analysis methods employed in this study are inclusive of the dynamic trajectories
of the rotor center and bearing center, power spectra, Poincaré maps and bifurcation diagrams. The maximum Lyapunov exponent
analysis is also used to identify the onset of chaotic motion. The modeling results provide some useful insights into the
design and development of rotor-bearing system for rotating machinery that operates at highly rotational speed and highly
nonlinear regimes. 相似文献
77.
78.
An integral equation formulation for buoyancy-driven convection problems is developed and illustrated. Buoyancy-driven convection in a bounded cylindrical geometry with a free surface is studied for a range of aspect ratios and Nusselt numbers. The critical Rayleigh number, the nature of the cellular motion, and the heat transfer enhancement are computed using linear theory. Green's functions are used to convert the linear problem into linear Fredholm integral equations. Theorems are proved which establish the properties of the eigenvalues and eigenfunctions of the linear integral operator which appears in these equations. 相似文献
79.
Sunyoung Cha 《Tetrahedron letters》2010,51(50):6663-6665
The chemosignaling of widely used peracid oxidant of m-chloroperbenzoic acid (mCPBA) by the selective desulfurization of thiocoumarin was investigated. Thiocoumarin was efficiently converted into its corresponding coumarin by the reaction with mCPBA, and resulted in a pronounced fluorescent turn-on type signaling. The conversion also provided a significant change in absorption behavior which allowed a ratiometric analysis. The effective signaling could be used as a convenient determination method for mCPBA in aqueous environment. 相似文献
80.
大型火箭起飞横向漂移测量系统研究 总被引:1,自引:0,他引:1
本文论及了大型火箭发射起飞段横向漂移量的近距离高速摄影测量系统和数据处理方法。 相似文献