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81.
Xueliang Jin Xiaoguang Yu Wei Zhang Jun Zhou Guipeng Tang ChaoFan Zhong 《应用聚合物科学杂志》2013,129(6):3104-3112
Dye‐sensitized solar cells (DSSCs) have attracted interest from chemists in recent years because of their unique advantages: low cost, simple preparation technologies, and high efficiency. Three main chain polymeric metal complexes F, P1, and P2 connected with thienyl(8‐hydroxyquinoline)–Cadmium (II) complexes have been synthesized by Heck coupling and characterized by Gel Permeation Chromatography, Fourier transform infrared, 1H NMR, thermogravimetric analysis, TGA, UV‐vis, cyclic voltammetry, photoluminescence (PL) emission spectra, and the application of dye sensitizers in DSSCs has been studied. The DSSCs exhibited good performance with a power conversion efficiency of up to 1.77%, under simulated air mass 1.5 G solar irradiation. They possess good stabilities, indicating the polymeric metal complexes are suitable for the fabrication processes of optoelectronic devices. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
82.
Composites of polyaniline in its emeraldine base form (PANI‐EB) and photo‐acid generators (PAG) show an increase in conductivity upon photo‐irradiation due to the protonation of PANI‐EB. Such materials may be utilized to fabricate conducting patterns by photo‐irradiation. However, the conductivity obtained by direct irradiation of PANI‐EB/PAG composites was normally quite low (<10?3 S/cm) due to aggregation of highly loaded PAG. In this work, poly(ethylene glycol) (PEG), which is a proton transfer polymer, was added to PANI‐EB/PAG. Results showed that addition of low Mw (550) PEG significantly enhance the photo‐induced conductivity. Conductivities as high as 10?1–100 S/cm were observed after photo‐irradiation. This conductivity is comparable to that of PANI‐salt synthesized by oxidizing aniline in the presence of an acid. High Mw (8000) PEG is much less effective than PEG 550, which is attributed to its lower compatibility with PANI. PEG‐grafted PANI (N‐PEG‐PANI) was also studied as an additive. Composites of PANI‐EB and N‐PEG‐PANI showed conductivity as high as 102 S/cm after treatment with HCl vapor. The photo‐induced conductivity of the N‐PEG‐PANI/PANI‐EB/PAG composite reached 10?2–10?1 S/cm. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
83.
Within this study relationships between material formulation and processing parameters and the morphology (vacuole formation) of thermotropic systems with fixed domains (TSFD) for overheating protection purposes were investigated. Main aim was on improving light shielding efficiency of TSFD based on UV curable acrylate resins by optimization of selected key parameters including photo‐initiator type and content, type of reactive diluent, radiation intensity/dose, and thermal treatment of layers during manufacturing. Variations of type of reactive diluent and thermal treatment had a minor effect on overheating protection performance. Utilization of photo‐bleaching photo‐initiator of acylphospine oxide type instead of a blend of conventional Type I (α‐hydroxy ketone type) and Type II (benzophenone) photo‐initiators enabled reduction of radiation dose to achieve properly cured layers. The results revealed that a significant reduction of radiation intensity/dose prevented formation of vacuoles. Consequently, light shielding efficiency of TSFD was enhanced significantly. Nevertheless, obtained scattering domain size was inappropriate for optimum light shielding efficiency and requires further optimization strategies. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3299–3310, 2013 相似文献
84.
85.
CdS quantum dot (QD) loaded WO3 films, fabricated by screen printing and short‐time chemical bath deposition (CBD) techniques, have been proven to have an efficient visible‐light‐driven photochromic response. One of the striking features of such a photochromic system is its remote photochromic characteristic. The photogenerated electrons in CdS are injected into WO3 to cause the color change of WO3, while CdS does not show any photochromism. Compared to bare WO3 films, the spectral sensitivity of remote photochromism in the CdS QD loaded WO3 films is red‐shifted. The onset wavelength for remote, the decoloration time for CdS QD loaded WO3 films was found to be significantly shorter than that for bare WO3 films, probably due to their different electron trapping processes. Bandgap excitation in bare WO3 creates deeply trapped electrons in the bulk, whereas the electrons injected from the QDs are trapped at shallow surface states in the remote photochromic system. The successful tailoring of photochromic coloration employing a simple procedure would provide numerous opportunities for designing photo‐ and electrochromic materials with the optimal architecture and tunable properties. 相似文献
86.
87.
Tobias Fischer Luuk J. G. W. van Wilderen Petra Gnau Jens Bredenbeck Lars-Oliver Essen Josef Wachtveitl Chavdar Slavov 《International journal of molecular sciences》2021,22(19)
The family of phytochrome photoreceptors contains proteins with different domain architectures and spectral properties. Knotless phytochromes are one of the three main subgroups classified by their distinct lack of the PAS domain in their photosensory core module, which is in contrast to the canonical PAS-GAF-PHY array. Despite intensive research on the ultrafast photodynamics of phytochromes, little is known about the primary kinetics in knotless phytochromes. Here, we present the ultrafast Pr ⇆ Pfr photodynamics of SynCph2, the best-known knotless phytochrome. Our results show that the excited state lifetime of Pr* (~200 ps) is similar to bacteriophytochromes, but much longer than in most canonical phytochromes. We assign the slow Pr* kinetics to relaxation processes of the chromophore-binding pocket that controls the bilin chromophore’s isomerization step. The Pfr photoconversion dynamics starts with a faster excited state relaxation than in canonical phytochromes, but, despite the differences in the respective domain architectures, proceeds via similar ground state intermediate steps up to Meta-F. Based on our observations, we propose that the kinetic features and overall dynamics of the ultrafast photoreaction are determined to a great extent by the geometrical context (i.e., available space and flexibility) within the binding pocket, while the general reaction steps following the photoexcitation are most likely conserved among the red/far-red phytochromes. 相似文献
88.
89.
The synthesis of 5,5′‐diformyl‐2,2′‐difuran (IUPAC name: [2,2′‐bifuryl]‐5,5′‐dicarbaldehyde) in good yields by the intermolecular coupling of 2‐furfural and 5‐bromo‐2‐furfural has been achieved. Optimum yields were obtained when mixtures of the substrates in acetonitrile were treated with polyvinylpyridine powder (Reillex 402), and irradiated with UV light through a quartz filter. Low yields of coupling product were obtained in the absence of this base or if hydrocarbon solvents were used. A mechanistic pathway involving a transient exciplex intermediate has been proposed. 相似文献
90.
Prof. Dr. Kenzo Fujimoto Ayumu Hirano Yasuha Watanabe Ami Shimabara Shigetaka Nakamura 《Chembiochem : a European journal of chemical biology》2021,22(24):3402-3405
Double duplex invasion (DDI) DNA is a useful antigene method that inhibits expression of genomic DNA. We succeeded in performing photoinduced-DDI (pDDI) using ultrafast photo-cross-linking. 5-Cyanouracil (CNU) has been used in pDDI to inhibit photo-cross-linking between probes, but its importance has not been clarified. Therefore, in this study, we evaluated the effect of spacer (S) and d-spacer (dS) that exhibit photo-cross-linking ability similar to that of CNU. CNU exhibited the highest pDDI efficiency, and S, dS, and T were not very different. The photo-cross-linking inhibitory effect was better with S and dS than with thymidine (T). Conversely, the thermal stability was significantly lower with S and dS than with T. The results suggest that the pDDI efficiency is determined by the balance between the photo-cross-linking inhibitory effect and the thermal stability, which is the introduction efficiency for double-stranded DNA. Therefore, CNU, which has a photo-cross-linking inhibitory effect and a high Tm value, showed the highest inhibitory efficiency. 相似文献