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351.
352.
用中国计量科学院提供的量热基准苯甲酸标定了本实验室建立的精密静弹燃烧热量计,测定了四邻甲氧基苯基卟啉(T_(o—OCH_3)PP)和四对二甲氨基苯基卟啉(T_(p—N(CH_3)_2)PP)的标准燃烧能,并计算出标准生成焓。实验仪器等温环境潜水式静弹燃烧热量计,量热环境主要包括恒温水槽和量热筒外套两部分,水槽中的两个泵式搅拌器能使水槽中的水充分搅动。量热体系包括量热筒、筒内定量的水、氧弹、内加热器、内搅拌器、热敏电阻测温探头以及一支辅助检测温度计。量热 相似文献
353.
采用INDO方法计算了{Fe[P(OMe)_3]_3(C_8H_(13))}~+的简化离子[Fe(PH_3)_3(C_8H_(13))]~+,将正则分子轨道用Edmiston-Ruedenberg定域化方法变换为定域分子轨道,结果表明:在对应C_1-H_(1A)键的定域分子轨道中,明显包含有铁原子轨道成分(7.8%),Fe-H_(1A)和Fe—C_1键级分别为0.190和0.302。指出C_1-H_(1A)键是以一对成键σ电子配位到铁原子上的。C_8H_(13)环以包含三个碳原子的η~4—共轭体系与铁原子相互作用。铁以二价(d~6-Fe(Ⅱ)的形式存在于该离子中。C_1-H_(1A)键的配位满足了文献[15]提出的Fe(Ⅱ)的共价12价。 相似文献
354.
用准经典轨线方法研究了处于振动激发态的硅原子团簇与硅原子团簇碰撞的反应动力学,计算表明,对于Si4+Si3反应,当反应物团簇处于振动激发态时,有利于生成更小团簇的碎片,而对生成Si6+Si及Si5+Si2的影响不大。 相似文献
355.
In this work, a new ligand, 2,9-bis[N,N-bis(carboxymethyl)-aminomethyl]-1,10-phenanthroline (BBCAP), was synthesized and
used to establish a novel fluorimetric method for the determination of trace amounts of terbium in a binary system. Its luminescence
mechanism was studied. The excitation and emission wavelengths are 284 nm and 547 nm, respectively. Other rare-earth metal
ions in 100-fold excess caused no interference. The fluorescence intensity was a linear function of the concentration of terbium
in the range of 5.0 × 10−10–1.0 × 10−6 mol/L. The detection limit was 2.0 × 10−11 mol/L (n = 12). The standard addition method was used to determine the terbium in a synthetic rare-earth sample with satisfactory
results. This method represents a direct, rapid, selective and sensitive analytical procedure with a widely linear range.
Received November 29, 2001 Revision February 9, 2002 相似文献
356.
Wen Xu Guoqun Liu Gang Xue Wentao Yu 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(8):m436-m438
The crystal structure of the title compound, (C16H36N)[Ni(C3S5)2], is isomorphous with that of the corresponding Pt complex but different from the structures reported for compounds of the same chemical composition, and so provides a new crystalline phase of this complex. The nickel complex anion has good planarity and lies on a crystallographic inversion centre. There is disorder in the two terminal C atoms of two of the butyl chains of the tetra‐n‐butylammonium cation, the N atom of which is located on a twofold axis. 相似文献
357.
Yang L Yang Z Cao W Chen L Xu J Zhang H 《The journal of physical chemistry. B》2005,109(23):11501-11504
The luminescence porous materials of CdTe or CdSe nanocrystals (NCs) were prepared by filling the corresponding NCs into the voids of colloidal crystal by co-deposition of polymer beads and NCs. After removing the beads with tetrahydrofuran (THF), the 3D-ordered porous materials of CdTe (or CdSe) NCs were obtained. The wavelength of maximum photoluminescence of the NCs porous material shows obvious red shift compared with their aqueous dispersion. Under the excitation of high-energy electron the porous materials of CdTe and CdSe NCs will emit photons that can be collected to form a cathode luminescence (CL) image. 相似文献
358.
[structure: see text] A series of ruthenium(II) complexes containing BINOL-based monodonor phosphorus ligands have been prepared and applied to the asymmetric catalysis of the hydrogenation of aryl/alkyl ketones. The best ligands for this application are those which contain an aromatic groups with either a methoxide or bromide on the ortho position. Using these ligands, alcohols with ee's of up to 99% are formed. 相似文献
359.
Pure rotational transitions of the weakly bound complex He-N(2)O and three minor isotopomers (He-(14)N(15)NO, He-(15)N(14)NO, and He-(15)N(15)NO) were measured in the frequency region from 6 to 20 GHz. Predictions for the microwave transition frequencies were based on the infrared work by Tang and McKellar [J. Chem. Phys. 117, 2586 (2002)]. In the case of (14)N containing isotopomers, nuclear quadrupole hyperfine structure of the rotational transitions was observed and analyzed. The resulting spectroscopic parameters were used to determine geometrical and dynamical information about the complex. An ab initio potential energy surface was calculated at the coupled cluster level of theory with single and double excitations and perturbative inclusion of triple excitations. This surface was constructed using the augmented correlation consistent polarized valence triple zeta basis set for all atoms with the inclusion of bond functions for the van der Waals bond. Bound state calculations were done to determine the energies of low-lying rovibrational levels that are supported by the potential energy surface. The resulting transition energies agree with the experimental values to 1% or better. 相似文献
360.