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121.
光敏电荷转移是近年来十分活跃的研究领域,人们设计了各种电子给体和电子受体用共价键相连结的化合物,如:卟啉电子给体,醌[1]、硝基苯、甲基紫精作为电子受体,模拟自然界的光合作用。 相似文献
122.
A. Yu. Tolbin M. O. Breusova V. E. Pushkarev L. G. Tomilova 《Russian Chemical Bulletin》2005,54(9):2083-2086
New boron μ-chloro-and μ-alkoxyhexabutylsubphthalocyanines were synthesized. A heteronuclear complex containing both the phthalocyanine
and subphthalocyanine fragments was prepared. The spectroscopic properties of these compounds were studied.
Dedicated to Academician N. S. Zefirov on the occasion of his 70th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2020–2023, September, 2005. 相似文献
123.
The effect of pigments of different chemical compositions on the crystellization process of PP was studied by means of differential scanning calorimetry in isothermal mode. The Avrami equation was applied to obtain the crystallization parameters of polypropylene with different pigments. Lipatov's equations were applied for evaluation of the thickness and volume content of the transition layers. Results show that pigments affect not only the degree of crystallinity but also the structure of the amorphous phase and the integrity of the crystalline/amorphous interphase. Finally, the morphology and mechanical properties of pigmented polypropylene were studied in view of the different chemical compositions of the various pigments. 相似文献
124.
Shane O’Malley 《Tetrahedron letters》2007,48(51):9003-9007
We report both the preparation and sensor evaluation of a new metal-free calixarene bridged binuclear phthalocyanine. 相似文献
125.
报道了Al/α-SnPc/ITO夹心结构的瞬态光电压随入射光强度和波长变化的演变特性和稳态连续光照射下的光电压作用光谱。稳态光电压作用光谱和其对应吸收光谱的变化趋势非常接近;而瞬态光电压的大小、极性和响应时间则共同取决于入射光的强度和波长。其中瞬态光电压的正峰部分(相对于ITO电极)只在较强的光照射下才出现,而且其响应时间也总是慢于同一条件下出现的负电压峰。文中对该现象的内在机制作了初步的探讨。 相似文献
126.
《Electroanalysis》2003,15(11):969-974
A novel electrode material was obtained by two consecutive procedures: (i) the electropolymerization of NiTAPc in DMF via the electro‐oxidative N–N coupling of the amino groups, to achieve a film denoted poly‐NiTAPc, followed by (ii) the electrochemical transformation of the poly‐NiTAPc film in alkaline aqueous solution to form the interconnected O? Ni? O oxo bridges. The obtained film is then denoted poly‐NiTAPc(OH). For the first time the electropolymerized poly‐NiTAPc coating shows a clear electrocatalytic activity towards Dopamine (DA) redox process, either as prepared or upon its electrochemical transformation in alkaline solution. Furthermore it clearly appears that poly‐NiTAPc(OH) film exhibits a much larger electrocatalytic behavior than the as‐prepared poly‐NiTAPc coating. This shows unambiguously the beneficial effect of the changes in the staking structure of the nickel phthalocyanine complexes upon the electrochemical treatment of the film in alkaline solution. It should be emphasized here that the increase in the oxido‐reduction currents related to DA on both films is not to be associated with any changes in the geometrical electrode area. This novel kind of material could present some interesting potentialities for a highly sensitive detection of others neurotransmitters. 相似文献
127.
Hari S Nalwa 《应用有机金属化学》1988,2(5):463-467
A monomer and polymer of a copper(II) phthalocyanine have been synthesized in order to develop structure-property relationships. Various electroactive properties such as dielectric constant, resistivity and thermally stimulated depolarization effects were investigated in order to examine the influence of extended conjugation. 相似文献
128.
F. Zamora M. C. Gonzalez J. J. Del Val 《Journal of Macromolecular Science: Physics》2013,52(5):601-613
The introduction of 2,9,16,23-tetracarboxy-Fe(III)phthalocyanine [Fe(III)tcPc] units onto fractions of poly(N-vinylcarbazole) (PVK) by Friedel-Crafts reaction leads to amorphous PVK-based grafted compounds that show major interchain distances by the wide-angle x-ray scattering (WAXS) technique. Glass transition temperatures of the products are lower than the main glass transition temperature of PVK and are attributed to local movements of the voluminous added groups. Dynamic thermogravimetric experiments show decarboxylation processes within the 250°C-500°C range and little weight loss. The large remaining residue, up to 70% of the sample at 800°C, is suggested to be the consequence of successive cross-linking reactions. The Fourier transform infrared (FTIR) spectrum of the residue is similar to that of the grafted sample before degradation. 相似文献
129.
In the presence of a pinning potential both the nature of the Peierls transition and the dynamics of the Charge Density Wave are affected. We argue that the periodic potential stabilizes phase solitons, while amplitude solitons can be polarons or bipolarons. For these excitations we give both the extension along the chain as well as the energies of formation. We only discuss the case of a periodic pinning potential as arising from a counterion lattice; neglecting randomness from impurities. 相似文献
130.
F. Cerdeira M. Garriga M. I. Alonso J. O. Oss F. Schreiber H. Dosch M. Cardona 《Journal of Raman spectroscopy : JRS》2013,44(4):597-607
We report Raman scattering measurements on azimuthally ordered thin films of F16CuPc, prepared by organic molecular beam deposition on A‐plane sapphire substrates. The observed peak frequencies have been compared both to the results of a model calculation for the vibrational modes of the free molecule and to those reported by other authors in related materials. This analysis provides a plausible identification of the modes responsible for the strongest spectral features. Detailed evaluation of the spectra reveals that some observed modes, which correspond to vibrations of the macrocycle inner ring, largely retain the intramolecular character and their polarisation properties can be used to study the orientation and stacking configuration of the molecules. We provide structural parameters deduced either in molecular or crystal symmetry considering the simpler possibilities, i.e. a single column molecular stacking and a herringbone‐like structure. The results suggest that the thicker and most ordered film is structurally close to the recently reported crystal organisation of bulk ribbon samples of this compound. The crystalline quality of the ordered films is mainly reflected in some other Raman peaks which are related to the motion of peripheral atoms and dominate the high wavenumber part of the spectra. These modes are affected by intermolecular interactions inducing Davydov splittings that are unequivocally identified by the observed Raman selection rules. The performed analysis also provides quantitative estimates of the degree of in‐plane ordering. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献