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101.
Investigation of the absorption and emission spectra (stationary and time-resolved) of phenanthroline-based polymers shows that the enforcement of a cisoid geometry in the bipyridine unit of the main chain via an ethenylene bridge does not significantly change the spectral and the deactivation behaviour. In close analogy to similar polymers, containing bipyridine units, the conjugation length in these polymers does not exceed ca. two chromophore units. At low temperatures, the model compounds show an additional, bathochromically shifted, intense luminescence with an increased lifetime which can be interpreted as an excimer (or aggregate) fluorescence. In addition, broad, superimposed emission bands arising from various aggregated species are observed. The relative intensity of these bands depends on the temperature processing occurring during cooling. Intersystem crossing is an insignificant deactivation channel.  相似文献   
102.
IntroductionSince the first report,in 1 990 ,of the electro-luminescence of the conjugated polymers in the filmof poly(p- phenylenevinylene) (PPV) sandwichedbetween an anode and a cathode of appropriatework functions[1] ,enormous efforts have been de-voted to the synthesis of light emitting poly-mers[2— 4 ] .Having been found potential applicationof conjugated polymers in photoluminescence(PL)and electro- luminescence (EL ) ,their importantproperties,polymer processability,band gap tun-abil…  相似文献   
103.
When thienyl Schiff base 1, derived from 2-formylthiophene and hydrazine, reacted with Fe2(CO)9 in n-hexane, three major complexes were obtained: (1) a diironhexacarbonyl complex with two 2-thienylmethylideneamido bridging ligands 2, which resulted from the =N---N= bond cleavage of ligand 1; (2) a doubly cyclometalated di-μ-di-(η12-thienyl; η11(N))bis(hexacarbonyldiiron) complex (3); and (3) a cyclometalated (μ-η12-thienyl; η11(N))hexacarbonyldiiron complex (4). Molecular structures of compounds 1a, 1c, and 2a have been determined by single-crystal X-ray diffraction.  相似文献   
104.
Sodium (3-dodecanoyloxy-2-hydroxy-propyl) succinate (SLGMS) is a conjugated anionic surfactant in which a glycerol residue connects with a hydrophilic sodium succinate and dodecanoate. Aqueous micellar phase (Wm), hexagonal (H1), bicontinuous cubic (V1), and lamellar (Lα) phases are successively formed with increasing the surfactant concentration in a binary SLGMS-water system. The Krafft point is below 0 °C. The effective cross sectional area per surfactant molecule, a s, in the H1 phase is almost constant, 0.5 nm2, and the shape of cylindrical micelle is almost unchanged with surfactant concentration. The cmc value of SLGMS measured by means of surface tension, electrical conductivity, and fluorescence probe methods is in the range of 4∼9 × 10−5 mol/l that is much lower than that of sodium dodecanoate, 2 × 10−2 mol/l, or SDS, 8 × 10−3 mol/l. Hence, it is considered that the polar glycerol part in the SLGMS acts as a hydrophobic part. The solubilization of oil in the SLGMS solution is much higher than that in the SDS solution and this also suggests that the glycerol and succinic units act as lipophilic moieties. Received: 15 June 2000/Accepted: 27 July 2000  相似文献   
105.
反相高效液相色谱法分析人体胆汁中结合型胆汁酸   总被引:1,自引:0,他引:1  
根据反相液相色谱的保留值方程IgK'=a+c.cb,结合型胆2汁酸的选择性变化规律lga=△a+△cv.cb及结合型胆汁酸的标准样品色谱保留值,对人体胆汁中6种结合型胆汁酸进行了定性定量分析。6种结合型胆汁酸的浓度在0~10.15g/L范围2内与相应的色谱峰高成良好的线性关系(相关系数在0.9996~0.9979之间)。  相似文献   
106.
Conjugated aromatic azomethines containing a carbazole group were synthesized. Their structures have been confirmed by IR, MS and UV spectrometries. When iodine was used as the dope to the conjugated compounds, the electrical conductivities (EC) of the doped conjugated compounds were increased by several orders of magnitude. The thermal stability of these two compounds investigated by TGA shows a good result, which guarantees the correct result of EC when the compounds are heated. As can be seen from the CV characterization of the electrochemical properties of these two compounds, the azomethine diamine and p-aminophenyl-9-ethylcarbazolyl azomethine possess electrochemical activity, which arises from the heteroatom of molecules.  相似文献   
107.
Benzothiadiazole(BT) is an electron-deficient unit with fused aromatic core, which can be used to construct conjugated polymers for application in organic solar cells(OSCs). In the past twenty years, huge numbers of conjugated polymers based on BT unit have been developed,focusing on the backbone engineering(such as by using different copolymerized building blocks), side chain engineering(such as by using linear or branch side units), using heteroatoms(such as F, O and S atoms, and CN group), etc. These modifications enable BT-polymers to exhibit distinct absorption spectra(with onset varied from 600 nm to 1000 nm), different frontier energy levels and crystallinities. As a consequence, BT-polymers have gained much attention in recent years, and can be simultaneously used as electron donor and electron acceptor in OSCs, providing the power conversion efficiencies(PCEs) over 18% and 14% in non-fullerene and all-polymer OSCs. In this article, we provide an overview of BTpolymers for OSCs, from donor to acceptor, via selecting some typical BT-polymers in different periods. We hope that the summary in this article can invoke the interest to study the BT-polymers toward high performance OSCs, especially with thick active layers that can be potentially used in large-area devices.  相似文献   
108.
合成了两个侧链含有2,2,6,6-四甲基哌啶-1-氧自由基单元(TEMPO)的1,4-吡咯并吡咯二酮(DPP)共轭聚合物PDPP4T-1和PDPP4T-2,并开展了其半导体性质研究。薄膜场效应晶体管器件测试结果显示,相对于不含TEMPO的聚合物PDPP4T,PDPP4T-1和PDPP4T-2的场效应器件性能有所降低,不过,含TEMPO的聚合物器件性能最高仍达到了2.12cm2·V-1·s-1。进一步通过原子力显微镜和X射线衍射对TEMPO引入后导致性能降低的可能原因进行了研究。  相似文献   
109.
The title compound was obtained by a convenient and scaleable three-step procedure, starting from the readily available and relatively inexpensive myo-inositol. The key-step of the route is an unprecedented tandem reductive elimination of two vic-dimesylate moieties to a conjugated diene.  相似文献   
110.
In recent years, water-soluble conjugated polymers have been attained much attention as the optical platform in fluorescent chemical and biological sensors1. In comparison to the small molecule counterparts, conjugated polymers exhibit signal amplificatio…  相似文献   
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