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81.
Yellow-green controlled photorelease: probes click-linked to peptide-coated gold nanospheres by a triazole ring can be released in living cells under a focused 561 nm laser at low power. Photocleaving follows a three-photon event stimulated by the excitation of the localized surface plasmon resonance.  相似文献   
82.
The road to molecular logic and computation in Belfast, Northern Ireland started with chemical sensors in Colombo, Sri Lanka. This journey is mapped out with reference to design principles, such as those for luminescent PET (photoinduced electron transfer) sensing. Applications such as those for blood electrolyte diagnostics, “lab-on-a-molecule” systems, and molecular computational identification (MCID) are also met along the way.  相似文献   
83.
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   
84.
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   
85.
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   
86.
Aspects of Phosphazene Research   总被引:2,自引:0,他引:2  
This review reports research carried out by the authors during the last 10 years. The research involves the synthesis, characterization, functionalization, and possible utilization of cyclo- and polyphosphazenes. The investigations concern the synthesis of poly(dichlorophosphazene) by polycondensation reaction of dichlorophinoyliminotrichlorophosphorane; the grafting of unsaturated organic substrates (maleic anhydride, maleates or vinyl polymers) onto poly(organophosphazenes) by free radical reactions and the use of the synthesized materials for the preparation of new grafted copolymers or for the superficial modification of conventional organic macromolecules; the synthesis of phosphazenes containing free hydroxylic groups by reaction of methoxy aryloxy- or methoxy oligoethyleneoxy-substituted cyclo- and polyphosphazenes with boron tribromide or trimethylsilyl iodide and their use for the preparation of new phosphazene-based materials (e.g., sol-gel hybrids, thermosetting resins, azodyes, cyclolinear inorganic–organic polymers sometimes containing chiral units, or organic macromolecules having cyclophosphazene residues as pendant groups); and the preparation of oxazoline-containing cyclic and polymeric phosphazene derivatives for the synthesis of photoinitiators, chain extenders, or blend compatibilizers. The possible developments of this research are also envisaged.  相似文献   
87.
纳米TiO2的光化学特性及其在环境科学中的应用   总被引:40,自引:2,他引:38  
纳米TiO2是一种优异的光电功能材料。介绍了其奇特的表面结构、优异的光化学特性及其光催化作用的机理,并概述了纳米TiO2在环境科学中有机污染物的光催化降解、重金属离子的光催化还原及光催化杀菌等方面的应用。  相似文献   
88.
89.
光化学研究进展综述   总被引:1,自引:0,他引:1  
陈建 《化工时刊》2005,19(9):63-65
主要对生物光化学、海洋光化学、环境光化学等进展进行综述,并对光化学应用和发展前景进行展望,提出了今后的重点研究方向.  相似文献   
90.
Compared to more conventional techniques, advanced oxidation processes (AOP) hold significant promise in terms of elimination of organic (especially persistent) compounds and microorganisms (disinfection) in wastewater. If the objective is to power these processes using solar energy, we need to be able to manage the intermittency in the solar resource. This is an essential step for design and to ensure efficient operation of the treatment processes. As solar radiation is inherently variable due to day/night cycles, seasonal cycles, and weather meteorological conditions, solar AOP performances are difficult to establish using conventional measures. To address this gap, we carry out experimental campaigns under controlled conditions and develop modelling tools capable of describing dynamic‐mode photocatalytic degradation. Here we develop a way to capture the responses of a photoreactor subjected to various stresses, including irradiation conditions, via an LED panel. Using a model that considers the influence of UV flux density and pollutant concentration made, it was possible to represent photoreactor responses under different irradiation conditions and feeds (concentration or flow at the input). The ultimate objective is to study the photocatalytic capacity of the photoreactor under irradiation conditions simulating a real day of sunshine.  相似文献   
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