Thiosemicarbazones and phenylthiosemicarbazones are in- teresting ligands because of their ability to form highly stable and intensely colored complexes, which is attributed to the for- mation of bond between sulfur and hydrazino nitrogen atoms, and these… 相似文献
Metal-free porphyrazine and metal porphyrazinates (M = Mg, Cu, Co or Zn) substituted with eight ferrocene moieties on the periphery through flexible alkylthio-bridges have been synthesised in a multi-step reaction sequence. The new compounds have been characterised by elemental analyses, i.r., 1H- and 13C-n.m.r., u.v.–vis. and mass spectra. The electrochemical investigation of porphyrazines indicates that all the ferrocene moieties are oxidised at the same potential, confirming the lack of any interaction among ferrocene groups or between ferrocenes and the porphyrazine core. 相似文献
We study an application services supply chain consisting of one application service provider (ASP) and one application infrastructure provider (AIP). The AIP supplies the computer capacity to the ASP that in turn sells the value-added application services to the market. The market is characterized by a price-sensitive random demand. The ASP’s objective is to determine the optimal price of its service to the market and the optimal capacity to purchase from the AIP. The AIP’s goal on the other hand is to maximize its profit from selling the capacity to the ASP. 相似文献
In the present work, beech wood condensates are separated from the aqueous phase. Experimental results reveal an electrostatic interaction between the oppositely charged wood extracts after oxidation and Ca(OH)(2). The increase in aqueous phase pH resulted in enhanced removal of wood extracts from water. The polarographic assays were carried out at 25 degrees C using a Gilson oxygraph equipped with a Clark electrode in order to determine the oxygen uptake during the oxidation reaction. The effect of pH is explained based on oxygen uptake. The organic compounds found in the aqueous effluent are responsible for the brown color. The objective of this study is to find the optimum pH to eliminate the wood extracts from the liquid effluents. 相似文献
We have studied bound states of the Schrödinger equation for a linear potential together with any finite number (P) of Dirac delta functions. Forx<-0, the potential is given as
A simple, verbal proof is offered that shows transportation algorithms automatically yield integral solutions when supplies and demands are integral. Thus, there is no need to avoid this aspect of the theory in introductory texts or in classroom presentations to non-mathematically sophisticated audiences. A fallout of the proof is the fact that tree solutions are basic and vice-versa. 相似文献
Journal of Fluorescence - A series of new chemosensor molecules bearing benzothiazole-, quinoline- and phthalazine-functionalized fluorene derivatives were synthesized and their complexation... 相似文献
The ion transfer reaction of 2-benzoylpyridine-thiosemicarbazone (HL), which has antimicrobial and antifungal properties and anticancer activity, has been studied to determine its lipophilicity by cyclic voltammetry at the water/1,2-dichloroethane (1,2-DCE) interface. The physicochemical parameters such as standard partition coefficient (IgP1) and the standard Gibbs energy of transfer (△G0,w→otr,I) of the protonated form of the ligand were measured as a function of pH in aqueous phase. The protonated form of the ligand exhibited reversible or quasi-reversible voltammograms at the 1,2-DCE in the range of pH 1-5. The protonation constants of the ligand, pKal, and pK? were determined spectrophotometrically and were found to be 12.14 and 3.24, respectively. The standard Gibbs energy of transfer (△G0,w→otr,N) and the partition coefficient of neutral species (IgPN) were also determined by the shake-flask method. The standard Gibbs energy of transfer of this compound across the water/1,2-DCE interface was evaluated as the quantitative measure of its lipophilicity. The difference between lgP1 and lgPN was related to the degree of charge delocalization and was used to evaluate qualitatively the lipophilicity of the ligand. 相似文献
The ion transfer reaction of 2-benzoylpyridine-thiosemicarbazone (HL), which has antimicrobial and antifungal properties and anticancer activity, has been studied to determine its lipophilicity by cyclic voltammetry at the water/1,2-dichloroethane (1,2-DCE) interface. The physicochemical parameters such as standard partition coefficient (lgPI) and the standard Gibbs energy of transfer ( ) of the protonated form of the ligand were measured as a function of pH in aqueous phase. The protonated form of the ligand exhibited reversible or quasi-reversible voltammograms at the 1,2-DCE in the range of pH 1–5. The protonation constants of the ligand, pKa1 and pKa2, were determined spectrophotometrically and were found to be 12.14 and 3.24, respectively. The standard Gibbs energy of transfer ( ) and the partition coefficient of neutral species (lgPN) were also determined by the shake-flask method. The standard Gibbs energy of transfer of this compound across the water/1,2-DCE interface was evaluated as the quantitative measure of its lipophilicity. The difference between lgPI and lgPN was related to the degree of charge delocalization and was used to evaluate qualitatively the lipophilicity of the ligand. 相似文献