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排序方式: 共有649条查询结果,搜索用时 15 毫秒
31.
CHAI X.D. CAO Y.W. YANG W.S. LU R. JIANG Y.S. BAI Y.B. LI T.J. Blanchard-Desce M. Lehn J.M. 《高等学校化学学报》1995,16(Z1):283
We investigated Langmuir-Blodgett(LB) films built from the mixture of an amphiphilic push-pull ferrocene derivative(P) and behenic acid. Langmuir films of P diluted by behenic acid exhibit a very good cohesion, and the mixed films can easily be transferred onto solid substrates. Linear dichroism UV-visible and IR spectroscopy measurements of the mixed LB multilayers confirm that the molecules(P) are oriented to the substrate. The nonlinear optical experiments on the mixed monolayer deposited on the CaF2 slide showed that P displays efficient optical second harmonic generation(SHG) with a molecular hyperpolarizability (β)h, high as 6.0×10-29e. s. u.. 相似文献
32.
Anne-Marie Caminade Jean-Pierre Majoral Valérie Maraval Rosa-Maria Sebastián 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6-7):1493-1497
Several series of phosphorus-containing dendrimers have been designed to study the variation of their properties, depending on the type, the location (surface, branches, core, and cavities), and the number of functions implied. 相似文献
33.
Fadong Yan Tomoya Higashihara Ravi Mosurkal Lian Li Ke Yang Rudolf Faust 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(11):910-913
Self organization and redox behavior of a ferrocene containing triblock copolymer, poly(vinylferrocene)-block-poly(isobutylene)-block-poly(vinylferrocene), with narrow molecular weight distribution in solutions and in thin films were investigated. Dynamic light scattering studies of the block copolymer in dilute solutions indicated that the polymer chains aggregated at relatively low concentrations. The aggregations of polymer chains were observed in toluene, as well as in tetrahydrofuran at concentrations as low as 0.014 mg/mL and 0.0045 mg/mL, respectively. Thin films of the copolymer showed reversible single electron redox behavior, similar to that of ferrocene. Morphology and micro-phase separation of the copolymer was analyzed by transmission electron microscopy. 相似文献
34.
35.
Yang Jie Wu Shou Quan Huo Li Yang Chen Xia Du 《Journal of organometallic chemistry》1995,490(1-2):249-254
Three series of cyclomercurated ferrocenylimines (2-chloromercurio-ferrocenylimines) have been studied using 13C NMR spectroscopy. Good to excellent linear relationships have been found to exist between the chemical shifts of the carbon atoms in the ferrocenyl moiety and normal Hammett substituent constants σm and σp. The δ values of the iminyl carbon atoms show excellent linear correlations with the σ values. In three series of the ferrocenes, the sensitivity of the carbon atoms to the substituent effect is different, which is discussed in terms of the twist angle between the N-phenyl ring and the C---C=N---C plane. The relative sensitivity of the chemical shifts on different positions in ferrocenyl moiety to the substituent effect has also been presented. 相似文献
36.
In this work, a voltammetric method has been developed for the simultaneous determination of captopril (CPT) and hydrochlorothiazide (HCT) in pharmaceutical combinations and clinical samples using a graphene/ferrocene composite carbon paste (GR/Fc/CP) electrode. The electrochemical behaviors of CPT and HCT were individually and simultaneously investigated at the surface of the GR/Fc/CP electrode. In differential pulse voltammetric (DPV) mode and under optimized experimental conditions, CPT and HCT gave linear responses over the concentration ranges 1.0–430 µM and 0.5–390 µM (r2>0.99), respectively. The prepared electrode could be used for simultaneous determination of CPT and HCT in some real samples. 相似文献
37.
The complex (ptppf)Fe(CO)3 has been prepared in high yield by the reaction of ptppf, l-(diphenyl-phosphino)-l'-(phenylthio)ferrocene, with (cis-cyclooctene)2-Fe(CO)3 in THF at ?60°C. The complex has been characterized by IR, 31P NMR, mass spectrometry and single-crystal X-ray diffraction. This compound is the first example of a ferrocenyl ligand having both sulfur and phosphorus donor atoms bound to a Fe(CO)3 moiety. X-ray crystallography shows that the two cyclopentadienyl rings are approximately eclipsed, a rotation of 13° from exactly eclipsed conformation. The tricarbonyl iron center has a trigonal bipyramidal geometry with sulfur occupying the equatorial site and phosphorus the axial site. Crystals of (ptppf)Fe(CO)3 are monoclinic, with a = 11.645(2), b = 14.304(1), c = 17.075(2) Å,β = 109.23(3)°, Z = 4, and space group P 21/n. The structure was solved according to the heavy-atom method and refined by full-matrix least-squares procedures to R = 0.037 for 2098 reflections with I ≥ 2.5σ(I). 相似文献
38.
二茂铁化学修饰电极测定丙二醛的研究 总被引:4,自引:0,他引:4
报道了在玻碳电极上共价键合二茂铁的新型化学修饰电极。研究了该电极对丙二醛的电催化作用。以微分脉冲伏安法测定丙二醛,方法具有较好的灵敏度和选择性。丙二醛的峰电流与其浓度在20×10-6~20×10-3mol/L呈良好的线性关系。 相似文献
39.
Masumi Itazaki 《Journal of organometallic chemistry》2005,690(17):3957-3962
1,4-Bis(dimethylsilyl)benzene reacted with [Pt3H(PEt3)3(μ-PPh2)3] at room temperature to yield trinuclear Pt complex [Pt3(SiMe2C6H4SiMe2H)(PEt3)2(μ-PPh2)3] (1a). Heating a solution containing an equimolar mixture of [Pt3H(PEt3)3(μ-PPh2)3] and 1a at 60 °C produced a hexanuclear Pt complex [(PEt3)2(μ-PPh2)3Pt3(SiMe2C6H4SiMe2)Pt3(PEt3)2(μ-PPh2)3] (2a). Complex 1a was characterized by X-ray crystallography and NMR spectroscopy, while the structure of 2a was determined by X-ray crystallography of single crystals containing 2a and [Pt3H2(PEt3)2(μ-PPh2)4] in 1:1 ratio. [Pt3(SiMe2fcSiMe2H)(PEt3)2(μ-PPh2)3] (fc = Fe(η5-C5H4)2) (1b) and [(PEt3)2(μ-PPh2)3Pt3(SiMe2fcSiMe2)Pt3(PEt3)2(μ-PPh2)3] (2b) were obtained similarly from the reactions of 1,1′-bis(dimethylsilyl)ferrocene with [Pt3H(PEt3)3(μ-PPh2)3] and characterized by NMR spectroscopy and elemental analyses. 相似文献
40.
《Electroanalysis》2005,17(20):1865-1869
A novel anion‐selective PVC membrane electrode based on bis‐[(3‐ferrocenyl)‐(2‐crotonic acid)] copper(II) complex [Cu(II)‐BFCA] as neutral carrier is described, which demonstrates excellent potentiometric response characteristics toward thiocyanate ion and anti‐Hofmeister selectivity sequence in following order: SCN?>I?>ClO >Sal?>Br?>NO >Cl?≈NO >SO >SO . The electrode shows a near‐Nernstian response for thiocyanate ion in a wide range of 9.0×10?7–1.0×10?1 M with a detection limit 6.8×10?7 M and a slope of ?59.1 mV/decade in pH 5.0 of phosphate buffer solution at 20 °C. The influences of lipophilic cationic and anionic additives on the response properties of the electrode were investigated. High sensitivity and wide linear dynamic range were observed for the electrode in the presence of hexadecyltrimethylammoniumborate (HTAB) as a lipophilic cationic additive. The electrode was successfully applied to the determination of thiocyanate ion in waste water and human saliva. 相似文献