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131.
Er Fu Huoa Yong Zoua Hui Qin Sunb Yan Huang Zhi Yun Lua Qing Jianga a College of Chemistry.Sichuan University Chengdu China b Analytical & Testing Center Sichuan University China 《中国化学快报》2011,(11)
Three novel conjugated polymers bearing 3,4-bis(4-hexylthiophen-2-yl)-3-cyclobutene-1,2-dione unit in their main chain have been synthesized successfully in good yields through Suzuki or Stille coupling reaction.Their molecular structures have been confirmed by FT-IR,~1H NMR and ~(13)C NMR.All these copolymers exhibit broad and strong absorption bands in UV-vis region,and their optical band gaps are calculated to be 1.6-2.0 eV.suggesting that they have good coverage with the solar spectrum.These polymers... 相似文献
132.
133.
Danuta Wrbel Andrzej Boguta 《Journal of photochemistry and photobiology. A, Chemistry》2002,150(1-3):67-76
In this paper we describe conversion of light energy into electric energy in a photoelectrochemical cell containing zinc phthalocyanine (ZnPc) dyes. For all dyes investigated in liquid polyvinyl alcohol with dimethyl sulfoxide solution and located in the photoelectrochemical cell the following measurements have been done: absorption, fluorescence, photoacoustic spectra, photovoltaic spectra, kinetics of photocurrent and current–voltage characteristics. It has been shown that all dyes located in the photoelectrochemical cell are able to convert light into electric energy but with different effectiveness. The influence of substituted different peripheral groups to ZnPc core and the correlation between the molecular structure and effectiveness of solar to electric energy conversion were observed and described. The unique behavior of ZnPc substituted with fluorines was indicated. 相似文献
134.
Valdemar I. Esteves Susana S.F. Lima Diana L.D. Lima Armando C. Duarte 《Analytica chimica acta》2004,513(1):163-167
The simultaneous separation and determination of organic acids in several samples of white and red Port wines was performed by capillary zone electrophoresis using indirect UV detection with 2,6-pyridinedicarboxylic acid as a background electrolyte buffer. Operational parameters like migration time, temperature, voltage and capillary length were optimized. Sixteen samples of red wine and four samples of white wine were used to analyze for tartaric, malic, lactic, succinic and acetic acids using glyoxylic acid as the internal standard. The method is rapid, sensitive and quantitative, and time-consuming sample preparation, such as solid-phase extraction or liquid-liquid extraction procedure, is not required. 相似文献
135.
LIJun-fen BAIGuan LINPei-hua TIANMei-lin DONGChuan LIDu-xin 《高等学校化学研究》2004,20(2):216-220
Five organic fluorescence dyes were synthesized by two- or three-step reactions. These synthetic meth-ods have an advantage of the simple processes, low costs and high yields. The compositions of the five compounds are characterized by IR, ^1H NMR, elemental analyses and fluorescence spectroscopies. The quantum yields of fluorescence were measured. 相似文献
136.
137.
P. LucenaA. Doña L.M. TobariaJ.J. Laserna 《Spectrochimica Acta Part B: Atomic Spectroscopy》2011,66(1):12-20
With the objective of detection and identification of explosives, different organic compounds, including aromatic nitrocompounds, RDX, anthracene, 2,4-diaminotoluene (DAT), 4-methyl-3-nitroaniline (MNA) and pentaerythritol (PENT) have been analyzed by laser induced breakdown spectroscopy (LIBS). To avoid the secondary ionization and to discriminate between the spectral contribution due to air from that of the compound in the plasma generated in air, the emission signatures from atomic lines (C at 247.9 nm, H at 656.3 nm, N at 746.8 nm and O at 777.2 nm) and molecular bands (CN at 388.3 nm and C2 at 516.5 nm) have been investigated in plasmas generated in air and in helium. The different possible pathways leading to the observation of molecular emissions have been studied, together with a discussion of the most useful tools for the explosives discrimination. Moreover, the effect of the laser fluence on the atomic and molecular emissions and their relationship with the oxygen balance of an organic explosive is presented. 相似文献
138.
The reactivity of five di-n-butyltin(IV) complexes, n-Bu2Sn(OR)2 (1), n-Bu2SnO (3), [n-Bu2Sn(OR)]2O (4), (n-Bu2SnO)2(CO2) (6) and (n-Bu2SnO)6[(n-Bu2SnOR)2(CO3)]2 (7) (R = CH3), with CO2, suggested as possible catalyst precursors and key-intermediates for the direct synthesis of dimethyl carbonate from carbon dioxide and methanol, has been investigated using high-pressure 119Sn{1H} NMR (HP-NMR) spectroscopy. Four of the five precursors studied, i.e. 3, 4, 6 and 7 give rise to an identical 119Sn{1H} NMR pattern which can be explicitly attributed to the fingerprint of the dimeric form of the 1-methoxy-3-methylcarbonatotetrabutyldistannoxane {5}2. However, with 1, a new pair of signals is observed in addition to the characteristic 119Sn{1H} NMR resonances of the dimeric hemicarbonato species {2}2 and {5}2, which can be attributed to the in situ formation of an unprecedented species suggested to be the trinuclear carbonato di-n-butyltin(IV) complex, 8. 相似文献
139.
Daungratchaneekron MeunmartNarid Prachumrak Tinnagon KeawinSiriporn Jungsuttiwong Taweesak SudyoadsukVinich Promark 《Tetrahedron letters》2012,53(28):3615-3618
A new highly fluorescent bis(4-diphenylaminophenyl)carbazole end-capped fluorene (TCF) is synthesized and characterized. TCF is an amorphous molecular glass with a high glass transition temperature of 169 °C, is electrochemically stable, and gives strong blue emission both in solution and solid state. It showed greater ability as a solution processed blue emitter and hole-transporter for OLEDs than commonly used NPB. High-efficiency, deep-blue and Alq3-based green devices with luminance efficiencies and CIE coordinates of 0.93 cd/A and (0.16, 0.09), and 3.78 cd/A and (0.29, 0.45) were achieved, respectively. 相似文献
140.
Xin ZhangGengxin Zhang Yen-Chih LiaoBrandon L. Weeks Zhao Zhang 《Journal of colloid and interface science》2012,387(1):175-179
A simple technique for patterning organic materials using a surfactant assisted lift-off method is proposed. Thin films of various organic materials are prepared, and areas in contact with a surfactant coated poly(dimethylsiloxane) (PDMS) stamp are selectively removed. The general applicability of this technique is shown for materials containing nitrate, amine, and carboxylic acid functional groups. This technique provides a new methodology for fabricating patterns with vertical dimensions ranging from 30 nm up to 3 μm on organic thin films with specific functional groups. 相似文献