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Poly(N-vinylcarbazole) layers containing tetra-5-crown-5-gallium phthalocyaninate (R4Pc)Ga(OH) are shown to possess photoelectric and photorefractive sensitivity at a wavelength of 1064 nm. This effect is associated with the formation of supramolecular ensembles of (R4Pc)Ga(OH) molecules with electronic optical absorption in the near-IR range and nonlinear optical properties. For the composite containing 5 wt % (R4Pc)Ga(OH) supramolecular ensembles, the dependence of the quantum efficiency of mobile-charge photogeneration on electric field E 0 is well fit by the Onsager equation expanded to E 0 3 at a quantum yield of electron-hole pairs of φ0 = 0.9 s with an initial separation radius of r 0 = 9.8 Å susceptibility χ(3) equal to 1.85 × 10?10 esu is measured via the well-known method of electric-field-induced second-harmonic generation. Two-beam-coupling gain coefficient Γ is found to be 80 cm?1 at E 0 = 120 V/μm.  相似文献   
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Complexing properties of lanthanide ions with respect to crown-substituted phthalocyanine are analyzed. Complexes of lanthanides (La, Nd, Sm, Eu, Gd, Tb, Yb, Lu, Y) with tetra-15-crown-5-phthalocyanine are synthesized and their structures are studied by photoelectronic, IR, 1H NMR, and mass spectrometry methods.  相似文献   
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含油岩心显微荧光成像光谱研究   总被引:6,自引:1,他引:5  
发展了一种显微荧光光谱成像技术,并将其应用于天然岩心进行显微荧光成像光谱研究。利用这种技术同时采集含油岩心表面的荧光光谱信息和空间信息.并对获得的光谱图像给予光谱学和地质学解释。结果表明,不但能显示岩心形貌和组分的大致趋势,而且能揭示其精细细节.为石油地质研究提供了一种新方法,为今后的石油勘探开发工作提供了一种先进的指导手段。  相似文献   
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ND Kataria  KS Daya  VG Das 《Pramana》2002,58(5-6):1203-1206
Analysis of a TE011 mode composite sapphire-rutile dielectric resonator has been carried out to study the temperature variation of resonance frequency, close to the Cs atomic clock hyperfine frequency of 9.192 GHz. The complementary behavior of dielectric permittivity with temperature of the composite has been exploited to obtain the desired turning point in the resonant frequency. The frequency of the composite structure is found to be independent of the shield diameter beyond four times the puck diameter.  相似文献   
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The cation-induced aggregation of sandwich crown-substituted complexes [Ln(R4Pc)2] (Ln = Lu (I) and Yb (II), R4Pc2? is the 4,5,4′,5′,4″,5″,4?,5?-tetrakis(1,4,7,10,13-pentaoxatridecamethylene)phthalocyaninate ion) and Ln2(R4Pc)3(Ln = Lu (III) and Yb (IV) in a CDCl3-DMSO-d 6 solution has been studied by 1H NMR. The data obtained are consistent with the conclusions concerning the composition of supramolecular aggregates drawn from spectrophotometric titration data. The molecules of double-decker complexes I and II form supramolecular oligomers, whereas triple-decker complexes III and IV form supramolecular dimers, which is presumably due to the stronger distortion of the planes of the outer decks of the triple-decker complexes as compared to their double-decker analogues.  相似文献   
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Erbium mono-, bis-, and tris(phthalocyaninates) with tetra-15-crown-5-phthalocyanine (H2R4Pc) were synthesized and studied by spectroscopic methods. The complexes were obtained by reacting H2R4Pc with erbium salts in high-boiling solvents. To compare the efficiency of two approaches to the synthesis of double-decker lanthanide phthalocyaninates, bis(phthalocyaninate) [Er(R4Pc)2] was also obtained by a template procedure from dicyanobenzo-15-crown-5. A combination of physicochemical methods (UV and IR spectroscopy, MALDI-TOF mass spectrometry, 1H NMR) was used for identifying the compounds and proving their individuality and structure. The photoluminescence method demonstrated that solutions of erbium bis- and tris(phthalocyaninates) in CHCl3 are nonfluorescent in the visible range of light whereas solutions of mono(phthalocyaninate) in CHCl3 and DMSO exhibit fluorescence with maxima at 707 and 695 nm, respectively. The oxidation of erbium mono(phthalocyaninate) leads to fluorescence quenching.  相似文献   
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The products of 4′,5′-dibromobenzo-15-crown-5 (I) cyanation by the Rosenmund-Braun reaction are studied by the 1H NMR and IR spectroscopy methods. X-ray diffraction analysis of two isolated products, i.e., di(4′,5′-dicyanobenzo-15-crown-5) 1.6 hydrate {(CN)2B15C5}2 · 1.6H2O (IIa) and 4′,5′-dicyanobenzo-15-crown-5,4′-cyano-5′-cyano(bromo)benzo-15-crown-5 dihydrate (CN)3.85Br0.15(B15C5)2 · 2H2O (III) is performed. Crystals IIa are monoclinic, a = 15.882(2) Å, b = 11.412(2) Å, c = 18.484(3) Å, β = 100.717(3)°, V = 3291.7(9) Å3, Z = 4, space group P21/c, R = 0.0746 for 4775 reflections with I > 2σ(I). Crystals III are monoclinic, a = 15.956(3) Å, b = 11.425(2) Å, c = 18.865(4) Å, β = 99.32(3)°, V = 3394(1) Å3, Z = 4, space group P21/c, R = 0.0692 for 2070 reflections with I > 2σ(I). Compounds IIa and III have similar structures with two crystallographically independent molecules in each (A and B in IIa; C and D in III). Four of the five O atoms of a macrocycle in molecules A and C form hydrogen bonds with the water molecules. The latter molecules lie above and below the cycle plane at a distance of ~2 Å from this plane. The A and C molecules have identical conformations (TTG TTG TTG TTG TTC) that differ from those of molecules B (TTG TGG STT SSG TTC) and D (TTC TSG STT SSG TTC).  相似文献   
10.
X-ray diffraction analysis was used to establish the structure of aluminum(iii) alkoxide tetra-15-crown-5-phthalocyaninate complex.  相似文献   
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