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91.
Chung SJ Zheng S Odani T Beverina L Fu J Padilha LA Biesso A Hales JM Zhan X Schmidt K Ye A Zojer E Barlow S Hagan DJ Van Stryland EW Yi Y Shuai Z Pagani GA Brédas JL Perry JW Marder SR 《Journal of the American Chemical Society》2006,128(45):14444-14445
Extended bis(donor)-substituted squaraine chromophores exhibit very high two-photon cross-sections (as high as 33 000 GM) in the near-IR; these can be attributed to the combination of large transition dipoles with small detuning energies. The modulus of the third-order nonlinear optical susceptibility at 1.3 mum has been found to be 7.0 x 10-11 esu for one of these chromophores. 相似文献
92.
93.
94.
基于结构方程(SEM)理论,以2008年统计数据为样本对影响城市现代化的测量指标进行了一阶、二阶验证性因素分析,得到了结构方程模型.并以测量指标在因子上的负荷、路径系数为基础构建权重,建立了城市现代化水平综合评价模型.对我国重要城市(直辖市、主要省会城市)现代化水平程度进行了相对评价,得到较为满意的结果. 相似文献
95.
Abbotto A Bruni S Cariati F Pagani GA 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2000,(8):1543-1552
The co-ordination geometry of the complexes M(bbtm)2 and M(bbom)2 (M: Co, Ni, Cu, Zn; bbtm, bis(2-benzothiazolyl)methanate; bbom, bis(2-benzoxazolyl)methanate) are discussed on the basis of their IR, Raman, resonance Raman, electronic and ESR spectra. Compounds of Ni, Co, Zn with both ligands and Cu(bbom)2 resulted to have a distorted tetrahedral geometry. The distortion towards a square planar geometry is more marked for the M(bbtm)2 series than for the M(bbom)2 one. It has been impossible to suggest a co-ordination geometry for Cu(bbtm)2, that probably has a polymeric structure. 相似文献
96.
Benzene equilibrium absorption curve by EPR rubber (50 wt % C3) was measured at 23°C. Benzene activity a1 was plotted against its volume fraction ?1. Benzene clustering function G11/v1 was calculated according to Zimm and the mechanism of formation of benzene clusters is discussed. It was found that clusters at very low benzene partial pressures are monomolecular and randomly distributed: at higher partial pressures, clusters increase in size. Flory-Rehner theory, giving activity α1 against ?1, was checked; predictions of cluster formation were made but there were some discrepancies with Zimm's conclusions. 相似文献
97.
Silvia Bradamante Silvana Colombo Giorgio A. Pagani Stefano Roelens 《Helvetica chimica acta》1981,64(2):568-571
Phenylglycine esters react with pyruvic acid to give α-methylsuccinic amides 9 instead of the expected Schiff bases 8 , analogously to p-anisidine but unlike aniline. 相似文献
98.
Silvia Bradamante Silvana Colombo Giorgio A. Pagani Stefano Roelens 《Helvetica chimica acta》1981,64(8):2524-2527
N-Substituted 9-fluorenimines 1 are easily prepared from primary amines or aminoesters and 9-fluorenimine: their conjugate carbanions 2 are formed by the action of alkoxides and are reprotonated to 1 or to the tautomeric 9-alkylidenamino-fluorenes 3 depending upon substituents. 相似文献
99.
Mario Paglialunga Paradisi Giampiero Pagani Zecchini Ines Torrini Gino Lucente 《Journal of heterocyclic chemistry》1990,27(6):1661-1664
The synthesis of linear dipeptides containing N-protected L-phenylalanine and (3R-cis)-tetrahydro-1,4-thiazine-3,5-dicarboxylic acid dialkyl diester residues is described. N-Deprotection of these dipeptides by hydrogenolysis on palladium afforded directly a mixture of cis and trans dioxopiperazines. The stereochemistry and the solution conformational properties of the cyclic dipeptides are determined. 相似文献
100.
G. Carturan E. Pagani R. Campostrini R. Ceccato 《Journal of Sol-Gel Science and Technology》1997,8(1-3):1115-1119
The variety of SiO2-gel structures allows the use of sol-gel derived materials as host matrices for prolonged release of chemicals. In this work,
the release of perfumed essences is studied in the case of hybrid SiO2 materials obtained from alkyl-modified silicon alkoxides. Thermogravimetric analysis in isothermal conditions at various
temperatures provide data on the kinetic release process. The effects of physical parameters (porosity reduction, vapour pressure)
and chemical interactions (organic molecules with matrix) are discussed for the interpretation of the results. 相似文献