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11.
12.
PHOTOCHROMISM AND LUMINESCENCE OF DOPANT CHROMOPHORES THROUGH TWO-PHOTON IONIZATION IN POLYMER FILMS
Two-photon ionization and recombination processes of an aromatic chromophore doped in polymer films werestudied and the features of these processes were discussed in relation to photofunctional polymers, An aromatic moleculehaving low ionization potential, e.g., N,N,N',N'-tetramethyl-p-phenylene diamine doped in poly(methyl methacrylate)(PMMA) film was easily photoionized by intense laser ligh excitation, giving a colored radical cation (photochromism) anda trapped electron in PMMA matrix. As a reversed process, the radical cation recombined with the trapped electron, showingdiscoloration and emitting luminescence, either isothermal luminescence (ITL), or thermoluminescence (TL). In this report,ITL and TL through the charge recombination process were studied and the luminescence was suggested as a mean of the read-out of photorecording. 相似文献
13.
Dr. Wangqiao Chen Dr. Yujie Song Dr. Liying Zhang Dr. Ming Liu Prof. Dr. Xiao Hu Prof. Dr. Qichun Zhang 《Angewandte Chemie (International ed. in English)》2018,57(21):6289-6293
Developing appropriate NIR‐reflective materials to combat near–infrared (NIR) heat radiation (700–2500 nm) from sunlight, avoiding energy accumulation and reduce energy consumption, is important and highly desirable. In this research, four thiophene‐fused‐heteroaromatic diones were used as basic reflectors to investigate the relationship between their intrinsic molecular structures and NIR‐reflective properties. The reflectance intensity can be readily tuned by adjusting the length of the appended aliphatic side chains, as well as the strength of the electron‐donating groups. A methoxy‐substituted thiophene‐fused‐heteroaromatic dione showed the best performance in reflecting NIR, and it was used as a coating for a model glass house. The comparison of the internal temperature difference relative to a control house was measured and the maximum temperature was 12 °C lower than that in the control house. 相似文献
14.
A simulation method is proposed to model electron–ion recombination in radiation tracks in liquid argon at 87 K. The method
is applied to calculate the electron escape probability in clusters of up to 20 pairs of electrons and cations that represent
a fragment of the track. The results reproduce the basic features of the track recombination in liquid argon observed in experiment. 相似文献
15.
Stefano Caramori Dr. Jérôme Husson Dr. Marc Beley Prof. Carlo A. Bignozzi Prof. Roberto Argazzi Dr. Philippe C. Gros Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(8):2611-2618
Mixtures of polypyridine FeII and CoII complexes are used as electron mediators in Ru–thienyltpy‐sensitised solar cells (tpy=terpyridine). The use of the metalorganic redox couples allows for improved charge‐collection efficiency with respect to the classical iodide/iodine couple which, when associated to Ru–tpy2 dyes, usually produces poor performance. The improved charge collection is explained by a combination of effective dye regeneration and decreased recombination with the oxidised electrolyte on the basis of data obtained by transient spectroscopy and photoelectrochemical measurements. The efficiency of the regeneration cascade is also critically dependent upon the ability of the CoII complex to intercept FeIII centres, as clearly indicated by chronocoulometry experiments. 相似文献
16.
纳米级包覆层厚度对染料敏化太阳电池中电子注入效率和电子寿命的影响 总被引:1,自引:0,他引:1
选取氧化钐作为包覆材料, 采用浸渍法对已烧结好的纳米TiO2多孔薄膜电极进行修饰, 并将其应用于染料敏化太阳电池中, 研究了纳米级氧化钐包覆层厚度及均匀性对染料敏化太阳电池中电子注入效率和电子复合过程的影响和作用机制. 结果表明, 包覆层厚度对电子注入效率和电子复合具有明显影响, 且电子注入效率和电子寿命随包覆层厚度的增加而呈现相反的变化趋势, 包覆层厚度在0.4 nm以内, 电池性能最好. 相似文献
17.
建立了环境中甾体类激素的生物荧光测定方法.利用睾丸酮丛毛单胞菌的生物酶基因与甾环结构特异的分子识别特性,结合绿色荧光蛋白(GFP)的荧光标记技术,通过基因同源重组技术建立了特异性生物荧光检测系统,实现对环境中甾环类化合物的灵敏监测.制备绿色荧光突变菌及总蛋白含量为1.0 g/L的非细胞体系工作液,在室温条件下对不同浓度雌二醇标准品进行检测,10 min即可检测出fg级的甾体类激素,最佳检测时间为30 min,方法的线性范围1.0~266 ng/L,灵敏度高于高效液相色谱方法.本方法可应用于环境的实际检验工作. 相似文献
18.
小批量制备质谱纯鲨鱼肝铁蛋白(Liver Ferritin of Sphyrna zygaena,SZLF)。在弱酸介质(pH1.0)中,天然电泳结果显示,SZLF蛋白质亚基20 min后开始解离。选用透射电子显微镜跟踪SZLF亚基解离与重组装全过程和蛋白壳与铁核尺寸变化,发现SZLF在亚基酸解离过程中,随着pH值的降低,铁核和蛋白壳的尺寸呈现相同的变化趋势,这种变化趋势可能与铁核内层铁的释放和蛋白壳的解离与去折叠有关。SZLF蛋白壳的重组装过程则是一个快速过程,并且是由松散熔球态向紧密态转变的过程。SZLF由单类型亚基组成,而马脾铁蛋白(Horse Spleen Ferritin,HSF)由H和L两种亚基类型组成。在基质pH3.0条件和激光辅助下,混合HSF和SZLF仍然可释放各自的亚基且形成准亚基离子,供基质辅助激光解析电离飞行时间质谱分析,说明此时SZLF的亚基间相互作用强度减弱但并没有去折叠。TEM技术在铁蛋白解离和重组装过程中的应用,为进一步研究铁蛋白纳米包装的过程和机理提供新颖的、可行的和更加直观的研究手段。 相似文献
19.
Fedushkin I. L. Kurskii Yu. A. Nevodchikov V. I. Bochkarev M. N. Müchle S. Schumann H. 《Russian Chemical Bulletin》2002,51(1):160-169
ansa-Metallocenes (5:5-C24H16)M(THF)2 (M = Sm (1), Yb (2), Ca (3)) and (5:5-C24H16)MI(THF) (M = Dy (8), Er (9), Tm (10), Lu (11)) were prepared in 50—90% yields by the in situ reactions of two equivalents of potassium acenaphthylenide K+C12H8
– with MI2 or MI3, respectively. Complexes 2 and 3 were also obtained by direct reduction of acenaphthylene with ytterbium and calcium naphthalenides, respectively. An ESR signal of the acenaphthylene radical anion, which was observed upon dissolution of compound 2 in THF, indicates that the [C24H16]2–
ansa-ligand dissociated into two [C12H8]·– radical anions. Hydrolysis of complex 2 in benzene afforded 1,1",3,3"-tetrahydro-3,3"-biacenaphthylene (4) and 3,3",4,4"-tetrahydro-3,3"-biacenaphthylene (5). The reaction of complex 2 with ZrCl4 and the reaction of compound 3 with Me3SiCl proceeded with the cleavage of the C—C bond between two acenaphthylene fragments of the [C24H16]2–
ansa-ligand to produce (2-C12H8)ZrCl2(THF)3 (6) and bis(trimethylsilyl)acenaphthene (Me3Si)2C12H8 (7), respectively. Compounds 1—3, 6, 7, and 11 were characterized by 1H and 13C NMR spectroscopy. The temperature dependence of the 1H NMR spectrum of compound 11 in tetrahydrofuran is indicative of the dynamic exchange of the solvent molecules in the coordination sphere of the Lu atom. After cooling of the solution to 210 K, the dynamic process was terminated as evidenced by the nonequivalence of the 1H signals of two acenaphthylene fragments. According to the X-ray diffraction data for complex 11, dimerization of two acenaphthylene radical anions at the Lu atom gave rise to the rac-ansa-metallocene structure. In compound 11, the Lu atom is 5-coordinated by two five-membered rings of the acenaphthylene ligands and also by the I atom and the THF molecule. The coordination environment about the Lu atom is a distorted tetrahedron. The average distance between the lutetium atom and the carbon atoms of the five-membered rings is 2.623 . 相似文献
20.
Photovoltaic Performance of Triphenylamine Dyes-sensitized Solar Cells Employing Cobalt Redox Shuttle and Influence of π-conjugated Spacers 下载免费PDF全文
Developing photosensitizers suitable for the cobalt electrolyte and understanding the structure-property relationship of organic dyes is warranted for the dye-sensitized solar cells (DSSCs). The DSSCs incorporating tris(1,10-phenanthroline)cobalt(II/III)-based redox elec-trolyte and four synthesized organic dyes as photosensitizers are described. The photovoltaic performance of these dyes-sensitized solar cells employing the cobalt redox shuttle and the influences of the π-conjugated spacers of organic dyes upon the photovoltage and photocur-rent of mesoscopic titania solar cells are investigated. It is found that organic dyes with thiophene derivates as linkers are suitable for DSSCs employing cobalt electrolytes. DSSCs sensitized with the as-synthesized dyes in combination with the cobalt redox shuttle yield an overall power conversion efficiency of 6.1% under 100 mW/cm2 AM1.5 G illumination. 相似文献