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101.
苝醌类化合物总量的测定   总被引:9,自引:1,他引:8  
用分光光度法测定了竹红菌、竹黄和菌寄生菌培养物中艹北 醌类化合物的总量 ;同时研究了以无水乙醇、丙酮和氯仿为溶剂提取 艹北 醌类化合物的相对效率 ,结果发现以丙酮为溶剂最合适。  相似文献   
102.
近几年,国外有机颜料生产公司增加了高档有机颜料的生产能力,生产的高档有机颜料品种包括苝系、异吲哚啉酮类、喹吖啶酮类、铜酞菁类、蒽醌类、二噁嗪类、特殊偶氮类和高档色酚类。我国的有机颜料生产企业在积极开发颜料新剂型的同时,也开发了苯并咪唑酮类、偶氮缩合类、喹吖啶酮类、苝系、吡咯并吡咯二酮类和喹酞酮类颜料等。有机颜料在世界范围每年以2%速度增长,而高档有机颜料以4%~5%速度增长,市场需求强劲。  相似文献   
103.
Three novel star-shaped S/Se-annulated perylene diimide (PDI) small molecule acceptors with triphenylamine as the core, namely TPA-PDI, TPA-PDI-S and TPA-PDI-Se, were designed and synthesized. Using the wideband-gap polymer PDBT-T1 as the donor and Se-annulated perylene diimide (TPA-PDI-Se) as the acceptor, power conversion efficiencies (PCE) of up to 6.10% was achieved, which is 38% higher than the reference of TPA-PDI without heteroatom annulation. Impressively, the S/Se-annulated perylene diimides as acceptors showed high open-circuit voltage (VOC) of 1.00 V. The high efficiency for TPA-PDI-Se can be attributed to complementary absorption spectra with the donor material, relatively high-lying LUMO level, balanced carrier transport and favorable morphologies. To the best of our knowledge, this PCE of 6.10% is among the highest values based on star-shaped non-fullerene acceptors so far.  相似文献   
104.
以市售1,6,7,12-四氯-3,4,9,10-苝四甲酸二酐(TCPBA)为原料,合成了中间体N,N'-二(2,6-二异丙基)苯基-1,6,7,12-四氯-3,4,9,10-苝四甲酸二酰亚胺(BDIP-TCPBI)和产品N,N'-二(2,6-二异丙基)苯基-1,6,7,12-四苯氧基-3,4,9,10-苝四甲酸二酰亚胺(苝红620),其结构经IR、MS和NMR进行了确证。结果显示:反应中引入催化剂二水乙酸锌,使BDIP-TCPBI的合成时间缩短了一半,纯度(HPLC,下同)较文献纯度(68%)高出16%,其最佳工艺条件为:n(TCPBA)∶n(2,6-二异丙基苯胺)∶n(二水乙酸锌)∶n(丙酸)=1∶4∶0.2∶107,120℃反应12 h,产率为88%,纯度为84%;使用简便的洗涤代替柱色谱法使苝红620的纯度较文献纯度(82%)高出9%。苝红620的斯托克斯位移值为35 nm,循环伏安法获得苝红620的LUMO和HOMO轨道能级分别为–4.144和–4.470 e V,且具有较小的荧光自吸效应,是一种潜在的电子受体材料。  相似文献   
105.
The effect of aza substitution at different sites of a benzimidazole derivative of a perylenetetracarboxylic-3,4,9,10 acid is investigated theoretically. These, as yet nonexistent aza derivatives have been subjected to theoretical analysis at PM3 (RHF) type semiempirical calculations. The results indicate that all the structures are stable but endothermic. Substitution of nitrogen on the bay region of the perylene core is more favored. The electronic and vibrational spectra have also been computed.  相似文献   
106.
ABSTRACT

New unsymmetrically substituted naphthalene and perylene imide imidazoles, N-(2-ethylhexyl)-naphthalene-3,4-(4,5-dicyano-1,2-benzimidazole)-9,10-dicarboxyimide and N-(1-heptyloctyl)-perilene-3,4-(4,5-dicyano-1,2-benzimid-azole)-9,10-dicarboxyimide, were synthesized via condensation reactions of diaminophthalonitrile and aromatic monoimide monoanhydride derivatives. Their structural analyses have been conducted by using general spectroscopic methods including FT-IR, 1H- and 13C-NMR, mass and elemental analysis. The molecular structure of naphthalene derivative was also determined by single crystal x-ray diffraction. Electronic absorption and emission properties were investigated on comparison. For studied compounds, both DFT and TDDFT calculations were carried out with the 6-311G(d,p) basis set, taking into account solvation effects by means of polarizable continuum model as implemented in the Gaussian 09 package.  相似文献   
107.
A pair of four-armed star and dicyclic 8-shaped poly(tetrahydrofuran)s, poly(THF)s, possessing a perylene diimide group at the core position (Ia and Ib, respectively) were synthesized by means of an electrostatic self-assembly and covalent fixation (ESA–CF) protocol. Mono- and bifunctional poly(THF)s having N-phenylpiperidinium salt end groups accompanying a perylene diimide tetracarboxylate as a counteranion were prepared by the ion-exchange reaction, and the subsequent covalent conversion by reflux in toluene afforded the corresponding core-fluorescent four-armed star and dicyclic 8-shaped poly(THF)s, (Ia and Ib, respectively) for the use of single-molecule fluorescence microscopy measurements.  相似文献   
108.
A highly crystalline perylene imide polymer (Urea-PDI) photocatalyst is successfully constructed. The Urea-PDI presents a wide spectrum response owing to its large conjugated system. The Urea-PDI performs so far highest oxygen evolution rate (3223.9 µmol g−1 h−1) without cocatalysts under visible light. The performance is over 107.5 times higher than that of the conventional PDI supramolecular photocatalysts. The strong oxidizing ability comes from the deep valence band (+1.52 eV) which is contributed by the covalent-bonded conjugated molecules. Besides, the high crystallinity and the large molecular dipoles of the Urea-PDI contribute to a robust built-in electric field promoting the separation and transportation of photogenerated carriers. Moreover, the Urea-PDI is very stable and has no performance attenuation after 100 h continuous irradiation. The Urea-PDI polymer photocatalyst provides with a new platform for the use of photocatalytic water oxidation, which is expected to contribute to clean energy production.  相似文献   
109.
110.
有机/高分子光诱导电荷转移材料研究   总被引:1,自引:0,他引:1  
光诱导电子转移是光电转换体系中发生的一个简单而重要的过程,即:在受到光激发时,一个电子从电子给体(D)转移到电子受体(A)并形成给体自由基阳离子(D·+)和受体自由基阴离子(A·-)的过程.与之相伴的另一个过程是后电子转移过程,即电子重新回到体系的最初状态的过程.为了使放热式电子转移过程顺利进行,最重要的决定因素在于电...  相似文献   
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