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1.
UV-Vis spectrum and the third-order nonlinear optical properties of the chiral camphor-derived β-diketonate have been studied at the B3LYP/6-31G* level. The results showed that the introduction of electron-drawing group-CF3 and-C3F7 on β-diketonate made the strongest absorption peak red-shift and the lowest energy absorption blue-shied. Introduction of-OC2H5 on the benzene or pyridine ring made the lowest energy absorption blue-shift. When the-C2H3 was introduced on the benzene or pyridine ring, the lowest energy absorption was red-shifted. Introduction of electron-donating group on β-diketonate can enlarge their nonlinear optical properties. On the contrary, the introduction of electron-drawing group dropped it down.  相似文献   
2.
The Poincaré-Bertrand formula takes an important position in the study of complex singular integral.The Poincaré-Bertrand formula on the complex sphere in the multidimensional complex Euclidian spaces was given by Sheng Gong.Using the method of solid angular coefficient,the authors extend the Poincaré-Bertrand formula on the complex sphere to the building domain of the complex biballs,and obtain a more general Poincaré-Bertrand formula with the solid angular coefficients.  相似文献   
3.
1 INTRODUCTION A number of hydroxypyrones and hydroxypyridinones are being assessed or considered as orally effective chelators for treatment iron or aluminum overload[1,2]. Almost all present and potential applications involve the tris-ligand complexes of metal(III) cations, as for example in administration of iron(III) complexes for the treatment of anaemia[3], and the appropriate isotopes (e.g. 67Ga, 111In, 90Y) for radiotherapy or the isotopes of gadolinium for magnetic resonance …  相似文献   
4.
1 INTRODUCTION Molybdenum(I) compounds, in particular Mo(I)-SR compounds, are rare amongst numerous Mo compounds. So far, only the following compounds [Mo2(CO)8-n(SR)2(CH_3CN)n] (R = C6H5, CH_2CO2Et, n = 0, 2)[1~5] have been reported in the literature. Recently, we make an effort to develop investigations on Mo(I) compounds on the basis of preparing new Mo(I) compounds by introducing different functional ligands into Mo2(SR)2(CO)8, then determining their structures and measur…  相似文献   
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6.
1 INTRODUCTION The design synthesis of metal oxide heterpoly compounds have been the subject due to their diverse structures and potential applications in catalysis, sorption, electrical conductivity, ion exchange and anti-virus[1]. Molybdenum phosphates with microporous framework serve as a new kind of inorganic microporous materials. In the course of our investigation on the synthesis of Molybdenum phosphates, we have hydrothermally synthesized an organically templated solid material[…  相似文献   
7.
1 INTRODUCTION  Organolanthanidecomplexeshavebeenextensivelystudied.However,thestud-iesofindenylrareearthcomplexeswererelativelylimited[1].Althoughaseriesoftri-indenyltetrahydrofuranatolanthanide((C9H7)3Ln·THF)havebeensynthesizedandstudiedbyTsutsuiandGyslingabout30yearsago[2],onlyafewcrystalstruc-turesofindenyllanthanidecomplexeshavebeenreported[1].Moreover,mostofthereportedindenyllanthanidecomplexesweresynthesisedbymetatheticalreactionsofanhydrouslanthanidetrichlorideswithindenyls…  相似文献   
8.
1 INTRODUCTIONItwasreportedthattheheterocycliccompoundscontaining1,2,4triazolo〔1,5a〕pyrimidinyldisplayedpotentialbiologicalactivities〔1,2〕.However,theherbicidalactivityofthe(thio)etherderivativesof1,2,4triazolo〔1,5a〕pyrimidinewasrarelyreported〔…  相似文献   
9.
1 INTRODUCTIONChiralphosphinesareusefulligandsinenantioselectivecatalysiswithtransitionmetalcomplexes〔1〕,someofthemderivedfromsugarsarealsoofpotentialapplicationsinbiphasiccatalysis〔2〕andmedicine〔3〕.Bythenucleophilicreplacementreaction,itisdifficul…  相似文献   
10.
1 INTRODUCTIONHeterometalpolynuclearcomplexeshavebeenthesubjectofmanyrecentstudiestoelucidatethemechanismofspincouplingbetweenthemetalions〔1,2〕,mimickingtheactivesiteofsomemetalenzymescontainingdissimilarmetalions,suchascytochromeoxidaseandsuperoxi…  相似文献   
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