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1.
Monomers and their polymers containing 3-arylcarbazolyl electrophores have been synthesized by the multi-step synthetic route. The materials were characterized by thermo-gravimetric analysis, differential scanning calorimetry and electron photoemission technique. The polymers represent materials of high thermal stability having initial thermal degradation temperatures in the range of 331–411 °C. The glass transition temperatures of the amorphous polymeric materials were in the rage of 148–175 °C. The electron photoemission spectra of thin layers of monomers showed ionization potentials in the range of 5.6–5.65 eV. Hole-transporting properties of the polymers were tested in the structures of organic light emitting diodes with Alq3 as the green emitter. The device containing hole-transporting layers of polyether with 3-naphthylcarbazolyl groups exhibited the best overall performance with a maximum current efficiency of 3.3 cd/A and maximum brightness of about 1000 cd/m2. 相似文献
2.
Prof. Dr. Hans-René Bjørsvik Prof. Dr. Bjørn Tore Gjertsen Dr. Vijayaragavan Elumalai 《ChemMedChem》2020,15(10):862-870
A previously designed and developed 12-step total synthesis that includes [1,1′-biphenyl]-2-amine and carbazole intermediates and that ultimately produces the carbazole alkaloid carbazomycin G was exploited as a screening compound library with the goal of identifying potential lead compound(s) with cytotoxic effect. These compounds were investigated by using in-vitro tests involving the two human cell lines HL-60 and MOLM-13, which both model acute myeloid leukaemia (AML). The in-vitro biological test results were used together with the molecular structures of the various intermediates in a concise SAR analysis. Several of the intermediates revealed cytotoxicity (IC50<10−4 M), although the final natural product carbazomycin G did not reveal cytotoxicity versus the two said human cell lines. 相似文献
3.
苏北盆地有上白垩统泰州组二段、古新统阜宁组二段、四段3套油源,母岩干酪根性质和地质环境十分接近,通过一般的地球化学指标很难彻底区分它们,为此因地制宜采用了多参数联合图版以及正烷烃分布、原生甾烷分布、三芳甾系列、二甲基咔唑系列等指标,使3套油源达到有效区分。值得提出的是,用于运移研究的二甲基咔唑系列分布在同源油之间也表现出惊人的稳定性,并且提供出进一步细分油源的指纹信息。 相似文献
4.
Mirzaagha Babazadeh 《应用聚合物科学杂志》2006,102(5):4989-4995
A new polymerizable monomer, [4‐(9‐ethyl)carbazolyl]methyl methacrylate ( 2 ), was synthesized by reacting of methacrylic acid and 4‐hydroxymethyl‐9‐ethyl carbazole ( 1 ) by esterification procedure in the presence of N,N′‐dicyclohexylcarbodiimide. The resulting monomer was then polymerized free‐radically to form the poly(methyl methacrylate) containing 4‐(9‐ethyl)carbazolyl pend ent groups. Also, copolymerization of monomer 2 with various acrylic monomers such as methyl methacrylate, ethyl methacrylate, methyl acrylate, ethyl acrylate, and n‐butyl acrylate by azobisisobutyronitrile as a free radical polymerization initiator gave the related copolymers in high yields. The structure of all the resulted compounds was characterized and confirmed by FTIR and 1H NMR spectroscopic techniques. The average molecular weight of the obtained polymers was determined by gel permeation chromatography using tetrahydrofurane as the solvent. The thermal gravimetric analysis and differential scanning calorimeter instruments were used for studying of thermal properties of polymers. It was found that, with the incorporation of bulky 4‐(9‐ethyl)carbazolyl substitutes in side chains of methyl methacrylate polymers, thermal stability and glass transition temperature of polymers are increased. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4989–4995, 2006 相似文献
5.
合成了一种共轭的咔唑二聚体荧光载体9-乙基-3-咔唑亚甲基-咔唑腙(ECCH),用PVC包埋的方法可以将它固定在光纤传感器的表面,在溶液pH值为2.0时,亚硝酸根(NO2-)与过量的碘离子(I-)反应生成的碘三离子(I3-)能猝灭此ECCH光极膜的荧光.得到了可以检测NO2-的传感器,并讨论了此传感器的传感机理.传感器具有较好的稳定性、重现性和选择性,使用寿命长等优点.NO2-测定的线性范围为1.0×10-6~1.0×10-4mol.L-1;检出限为4.0×10-7mol.L-1.将传感器用于水样中NO-2的直接测定,回收率在96.0%~103.6%. 相似文献
6.
Copolymers of 9,9-dioctylfluorene (DOF) and 2-thienyl-benzothiadiazole (DBT) were synthesized by Suzuki reaction and end-capped
by N-hexyl-carbazole and benzene, which were abbreviated as PDOF-DBT-Cz and PDOF-DBT-B, respectively. The photophysical, electrochemical
and thermal properties of the copolymers were studied. The results indicated that replacement of N-hexyl-carbazole as end-capping
group of PDOF-DBT can vary light color and improve luminescence efficiency.
Supported by the Major Project of Science Foundation Ministry of Education of China (Grant No. 207015) and the National Natural
Science Foundation of China (Grant No. 20671068) 相似文献
7.
Martial Degbia Bruno Schmaltz Johann Bouclé Juozas V Grazulevicius François Tran‐Van 《Polymer International》2014,63(8):1387-1393
The synthesis of new organic hole transporting materials (HTMs) based on 3,6‐disubstituted 9H‐carbazole‐3,6‐diamine,N,N,N′,N′‐tetraphenyl‐9‐(4‐methoxyphenyl) derivatives and their applications in solid state dye sensitizer solar cells (DSSCs) are described. The effect of the methoxy group localized on the para position of the diphenylamine moieties on the thermal, electronic and electrochemical properties and photovoltaic performance is discussed. In solid state DSSCs, utilization of the aforementioned HTMs in combination with the dye D102 (TiO2/D102/HTM/Au) shows a positive influence of the methoxy group on the photovoltaic conversion efficiency compared with unsubstituted diphenylamine grafted groups. A study on the concentration of the HTM is also carried out and shows an optimal concentration around 200 mg mL?1. Without further optimization, the best device gives a power conversion efficiency of 1.75% under AM 1.5 solar irradiation (100 mW cm?2). 相似文献
8.
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10.
Klebsiella sp.LSSE-H2的咔唑降解 总被引:1,自引:0,他引:1
从染料污染的土壤中分离出1株新的咔唑降解菌LSSE-H2,能以咔唑作为唯一的碳源、氮源和能源. 依据16S rRNA基因序列的系统发育分析将该菌鉴定为Klebsiella sp. 该菌在30℃、以咔唑为唯一的碳源、氮源的选择性培养基(CNFM)中,经过56 h可将浓度为12 mmol/L的咔唑几乎完全降解,在浓度为16 mmol/L的咔唑中也同样表现出高的咔唑降解活性. 对比分析不同营养成分培养基中对咔唑的降解情况表明,LSSE-H2可能存在独特的咔唑降解活性表达调控模式. 按照已公布的car基因簇序列设计同源引物,PCR扩增出LSSE-H2的包含5个咔唑降解基因的car基因簇片断,测序结果表明,咔唑降解基因高度保守,与Sphingomonas sp. KA1和Sphingomonas sp. GTIN11相应的咔唑基因的同源性都达到100%,只在基因簇的非编码区上发现少数碱基不同. 对比研究表明,LSSE-H2, KA1和GTIN11中car基因簇的起源可能相同,并能在不同的细菌之间水平转移. 相似文献