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11.
12.
A novel elastic polymer containing 4,4′-bipyridinium salts with tetrakis[3,5-bis(trifluoromethyl)phenyl]borate as part of the main chain was synthesized. The cast film showed persistent and reversible colour changes due to photoinduced electron transfer upon excitation of an ion-pair charge-transfer band (ex >365 nm) in vacuo. The lifetime of the coloured state markedly depended on temperature. The optically written data were stored without decay below 0°C and were erased thermally at elevated temperatures. The colour changes were reversibly repeatable for many times. 相似文献
13.
The environmental and socio‐economic impacts of biomass utilization by co‐firing with brown coal in an existing thermoelectric unit in Greece or through its pure combustion in a new plant were studied and evaluated in this work. The 125 MWe lignite‐fired power plant in Ptolemais Power Station (Western Macedonia) was used as reference system. The environmental benefits of the alternative biomass exploitation options were quantified based on the life cycle assessment methodology, as established by SETAC, while the BIOSEM technique was used to carry out socio‐economic calculations. The obtained results showed clear environmental benefits of both biomass utilization alternatives in comparison with the reference system. In addition, co‐firing biomass with lignite in an existing unit outperforms the combustion of biomass exclusively in a new plant, since it exhibits a better environmental performance and it is a low risk investment with immediate benefits. A biomass combustion unit requires a considerably higher capital investment and its benefits are more evident in the long run. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
14.
Monodisperse poly(vinyl acetate) (PVAc) microspheres with high molecular weight obtained by suspension polymerization of vinyl acetate were saponified in alkaline aqueous solution to keep their spherical structure. The saponification was restricted on the surface of the PVAc microspheres and obtained particles had skin/core structure. Various poly(vinyl alcohol) (PVA) microspheres with different diameters and degrees of saponification (DSs) were obtained. The conversion of PVAc to PVA during the heterogeneous surface saponification time were examined by nuclear magnetic resonance spectroscopy and after 72 h hydrogel type PVA microspheres completely saponified were obtained. The crystal melting temperatures of the microspheres obtained by the saponification were measured a constant value of 238°C irrespective of varying DS, and the peaks became enlarged as reaction time. Iodine complexes were formed in saponified microspheres with DS of 41% and 99% by immersing them in I2/KI aqueous solution and decomposed by the reduction of I2 in the complexes to 2I? using sodium sulfite to confirm whether the skin formed through the saponification was composed of PVA with high VA content. Obviously, characteristic blue color developments owing to I5?‐PVA complexes were observed in both saponified regions and a red in the PVAc core. Consequently, it was concluded that the PVA skins formed by heterogeneous surface saponification had high DSs. Such complexes endowed polymeric microspheres a good radiopacity which would be useful in clinical treatment of vascular diseases and were examined by X‐ray irradiation image. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
15.
Using nickel-2,2′-dipyridyl complex as a template, N-vinyl-2-pyrrolidone as the metal coordination functional monomer, and ethylene glycol dimethacrylate as the crosslinker, polyvinylidene fluoride (PVDF) hollow fiber ultrafiltration membrane as the supported membrane, metal complex imprinted polymeric membranes were prepared. The association constant of template-monomer interaction in the prepolymerization solution was estimated to be 4.38 × 104 (L/mol)2 by spectrophotometric titration analysis. The attenuated total reflection Fourier transform infrared spectroscopy and scanning electron micrograph characterization indicated that the surface of the support PVDF membrane was completely coated by the imprinted polymer layer after modification. The imprinted membranes exhibited the selective permeability for the template in certain nickel acetate solution. The molecularly imprinted membranes gave higher permeation separation factors at about pH 6, whereas increasing pressure would lower the separation ability. The effects of ion concentration, cations and counterions, ligand selectivity, pH, and trans-membrane pressure were investigated and the permeation performances of the imprinted membranes could be regarded as facilitated transport mechanism. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
16.
17.
Veysel T. Yilmaz Evrim Senel Canan Kazak 《Journal of Inorganic and Organometallic Polymers and Materials》2008,18(3):407-413
The reaction of [Cu(sac)2(H2O)4] · 2H2O with 2-methylpyrazine (mpyz) leads two complexes, concomitant crystallization of a mononuclear complex [Cu(sac)2(mpyz)(H2O)2] (1) and a polymeric complex [Cu(sac)2(μ-mpyz)]n (2). Both complexes have been characterized by elemental analyses, magnetic measurements, FT-IR and ESR, TG-DTA and single-crystal
X-ray diffraction analyses. Single-crystal X-ray analyses show that complex 1 consists of discrete molecules in which the copper(II) ions exhibits a square-pyramidal coordination geometry. The individual
molecules of 1 are connected into a hydrogen-bonded chain structure, which is further assembled to form a three-dimensional network by π–π stacking interactions.
Complex 2 is an 1D coordination polymer in which copper(II) centers are bridged by the mpyz ligand. The chains are further assembled
to form two-dimensional frameworks by π–π and C–H···π stacking interactions. 相似文献
18.
三(明)钢烧结厂电除尘灰的气力输送 总被引:1,自引:1,他引:0
三钢烧结厂130m^2烧结机电除尘输灰首次采用了气力输送系统。该系统由气源、输送、管路、灰库及控制五部分组成,本文介绍了系统的工作原理及运行调试情况。系统投产后,运行平稳,达到了设计要求。 相似文献
19.
Hironori Oda 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1995,63(3):223-228
Fluorans are given considerable attention as functional dyes for heat-and/or pressure-sensitive recording media. Numerous potential metal complexes were synthesised to prolong the life of coloured species. The protecting effect of these compounds against the photofading was examined on cellulose. It was found that the zinc or nickel salts of 3,5-dihydroxy-2-naphthoic acid and its derivatives can be applied as effective stabilisers against the fading of fluoran dyes. 相似文献
20.
C. Llopis F. Revents L. Batet C. Pretel I. Sol 《Nuclear Engineering and Design》2007,237(18):2014-2023
The Technical University of Catalonia (UPC) has been jointly working with the Asociación Nuclear Ascó-Vandellòs (ANAV) for a number of years in order to establish, qualify and use best estimate (BE) models for the reactors under the control of ANAV. ANAV is the consortium that is responsible for operation of the Ascó and Vandellòs-II reactors. The reactors are Westinghouse-design three-loop PWRs with an approximate electrical power of 1000 MW. The existing integral plant models for each plant are currently used for many different purposes among which are support of plant operation and control. Quite a number of studies have been done in order to improve both safety and plant competitiveness. Most of these dynamic analyses were carried out in relation to transients starting at nominal full power or at least, very close to full power. This paper develops a specific use of the Vandellòs-II plant model for operation and control support at low power involving new ranges of system actuation parameters. It also examines scenarios that are somewhat different from those typically analysed. The study starts showing the results of an assessment case, which is a start-up test and provides some additional qualification, and subsequently attempts to establish calculations to support both an improvement in feed water controls and to set up operating recommendations for low-load manual operation of feed water turbo-pump. Both results hopefully, will produce an outcome, which leads to an improvement in safety and reduces reactor trip probability. 相似文献