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991.
H_2TPP与AgNO_3在乙醇中的光反应 总被引:1,自引:0,他引:1
用紫外可见吸收光谱研究了 5,10 ,15,2 0 -四苯基卟啉 (H2 TPP)的乙醇溶液与AgNO3的乙醇溶液混合后 ,在光照条件下的化学反应。谱图显示H2 TPP发生络合反应 ,生成其二价银络合物Ag(Ⅱ )TPP。银胶能加快该反应的速度。 相似文献
992.
Dispersion of MoO3, NiO, ZnO on rutile TiO2 with low specific surface area was studied with Mercury Porosimeter, SEM, XPS and Ammonia Extraction method. The dispersion thresholds of MoO3, NiO, ZnO on three rutile TiO2 carriers were obtained with XPS, and com-pared with those on anatase TiO2 with high specific surf are area. Ammonia Extraction method was used to identify the surface oxide species interarting with support surface in different strength and it was found that the proportions of oxides that can not be extracted by ammonia extraction are different for MoO3, NiO and ZnO which are supported on rutile TiO2. 相似文献
993.
994.
995.
The stable structures and vibrational spectra of protonated acetone molecule clusters with different sizes (CH3COCH3)nH +(n=1-7)are calculated at the 6-31G(d)level by means of density functional theory (B3LYP)quantum chemical calculations. The corresponding energies are analyzed at the level B3LYP/6-311+G(3df,2p)in order to obtain more accurate results. The proton affinity of neutral cyclic acetone molecule clusters increases with the increasing of cluster size. The calculated results show that the protonated acetone clusters have certain growth regularity with forming a solvation shell at the beginning and then new added acetone molecule attacking different active sites including the middle carbon atoms and the different methyl in solvation shell. The IR spectra of the protonated clusters are more complicate than that of neutral ones. The strongest peaks result from the movement of the proton between the two oxygen atoms in solvant shell apart from the case of n=1. Carbonyl stretching vibraional peaks split into the more and more and in general the corresponding intensities are weakened due to the protonation with the increasing of cluster size. 相似文献
997.
(6aR,11aR)-4,9-dimethoxy-3-hydroxypterocarpan was isolated from the natural plant of Caragana spinifera Kom (Leguminosae). The structure was elucidated by infrared spectra(IR), mass spectrometry(MS), 1H-Nuclear magnetic resonance(1H-NMR),13C-Nuclear Magnetic Resonance(13C-NMR), 1H-1H correlation spectroscopy(1H-1H COSY), heteronuclear multiple quantum coherence(HMQC) and heteronuclear multiple bond coherence(HMBC). In addition, its crystal structure was determined by the single-crystal X-ray diffraction analysis. It crystalized in monoclinic, space group P21 with a=6.4778(13), b=12.631(3), c=8.8368(18)(A), β= 95.8(3)o, C17H16O5, Mr=300.30, V=719.3(3)(A)3, Z=2, Dc=1.386 Mg/m3, F(000)=316, μ=0.102 mm-1, the final R=0.0332 and wR=0.0862 for 1533 observed reflections (I>2σ(I)). The molecular backone of the compound includes a benzofuro and a benzopyran. The X-ray analysis shows that the absolute configuration of the compound is cis-pterocarpan. 相似文献
998.
The potential energy surface for the decomposition and isomerization of Chlorine Nitrate(ClONO2)is calculated using the G3 theory. Geometries of related species are optimized at the MP2( full)/6-31+G(d)and B3LYP/6-31+G(d)level. Vibrational frequencies and IR intensities of ClONO2 have been calculated at the same level. Obtained geometries and vibrational frequencies as well as IR intensities for ClONO2 are in good agreement with experimental values. A new stable stereoisomer is verified by CCSD(T)and QCISD(T)methods at 6-311G (d)basis set. Calculated geometries using above methods for this stereoisomer are in accord with each other. The calculated reaction heat of ClONO2 are also in good agreement with the available data in the literature. Among these reactions of ClONO2,the stereoisomer reaction is the hardest one. The barrier height for this reaction is 481.52 kJ/mol relative to ClONO2 and the reaction is endothermic by 299.85 kJ/mol. On the other hand,among these unimolecular reactions of ClONO2,the decomposition reaction of NO2+ClO is the easiest one. These results indicate that ClONO2 is very stable. 相似文献
999.
The photoluminescence(PL) and the electroluminescence(EL) properties of a novel organic compound, 2,5-bis(2,2′-bis(5-phenyl)-1,3,4-oxadiazole(T-OXD), were studied in chloroform and in a solid thin film. The PL and the EL properties of T-OXD/poly(9-vinylcarbazole)(PVK) blends were also studied, which contained various contents of T-OXD. The PL maximum emission peaks of T-OXD/PVK blends show gradual bathochromtic-shift with the increase of the T-OXD content. The EL spectra of T-OXD/PVK devices are similar to their PL spectra, and all the EL maximum emission peaks show bathochromtic-shift compared with the corresponding PL spectra, which is ascribed to the formation of electroplex. The turn-on voltages for ITO/T-OXD:PVK/Al devices decreased from 13.5 V of the device cotaining 0.1% T-OXD(mass fraction) to 5 V of the device containing 5% T-OXD, which suggests that T-OXD improves the energy level match between T-OXD and PVK and enhances the emission efficiency. The experimental results indicate that T-OXD can be used as a good electron transporting material. 相似文献
1000.