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1.
4-Morpholinoacetophenone thiosemicarbazone, MAPT, and its nickel(Ⅱ) and copper(Ⅱ) complexes have been prepared and characterized by elemental analysis, magnetic susceptibility, spectral methods (FT-IR, ^1H NMR) and cyclic voltammetry. Electrochemical behaviors of the complexes have been studied by cyclic voltammetry in DMF media showing metal centered reduction processes for both of them. The redox properties, nature of the electrode processes and the stability of the complexes were discussed. [Cu(MAPT)2]Cl2 complex shows Cu(Ⅱ)/Cu(Ⅰ) couple and quasi-reversible wave associated with the Cu(Ⅲ)/Cu(Ⅱ) process. The reduction/oxidation potential values depend on the structures of complexes. Also, the antimicrobial activities of these complexes were determined against S. aureus, E. coli and B. subtilis.  相似文献   
2.
Summary 4-Benzoyl-5-phenylfuran-2,3-dione (1) and the urethanes2 combine under loss of carbon monoxide yielding the open chain dibenzoylacetic acid derivatives3 and4. 3a, b only can be cyclized to the oxazinone5. The keto-enole tautomerism3 4 is further investigated with aid of semiempirical quantum chemical calculations, based upon the molecular geometry of3a, deduced from an X-ray study.
Frau Univ. Prof. Dr. Helga Wittmann mit den besten Wünschen zum 70. Geburtstag gewidmet.  相似文献   
3.
We show that the ground state energy is bounded from below when there are infinitely many attractive delta function potentials placed in arbitrary locations, while all being separated at least by a minimum distance, on two dimensional non-compact manifold. To facilitate the reading of the paper, we first present the arguments in the setting of Cartan–Hadamard manifolds and then subsequently discuss the general case. For this purpose, we employ the heat kernel techniques as well as some comparison theorems of Riemannian geometry, thus generalizing the arguments in the flat case following the approach presented in Albeverio et al. (2004).  相似文献   
4.
A path-dependent representation for the effective hamiltonian in the large-N limit of a gauge theory is given. It explicitly satisfies all of the field theoretical requirements except for the equations of motion. The latter can be used to derive a consistency condition for the Wilson amplitudes.  相似文献   
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The transfer of heavy metal ions across the polarized water/1,2‐dichloroethane (1,2‐DCE) interface assisted by 9‐ethyl‐3‐carbazolecarboxaldehyde‐thiosemicarbazone (ECCAT) in the 1,2‐DCE phase has been studied by cyclic voltammetry. Voltammetric waves of Pb(II) and Cd(II) ions were reversible and quasi‐reversible, respectively, whereas that of Hg(II) and Zn(II) ion were irreversible. The voltammogram of Cu(II) ion showed a two‐step wave, however the nature of the transfer could not be satisfactorily evaluated by analyzing the cyclic voltammetric data. When Ni(II) and Co(II) was used no peak was visible under the experimental conditions used in this study. The dependence of the half‐wave potentials of Pb(II) and Cd(II) ions on the ligand concentration reveals that their ion‐transfer is assisted by the formation of 1:3 metal‐ECCAT complex in 1,2‐DCE. The over‐all association constants of [Pb(ECCAT)3]2+ and [Cd(ECCAT)3]2+ complexes in DCE‐phase have been determined to be log β =14.03 and log β =15.44, respectively.  相似文献   
8.
Properties of Te? Te Bonds. IV. Dismutation Reactions of Di-p-tolylditelluride with Tetra-tert-butyldiphosphane and Tetra-isopropyldiphosphane Di-p-tolylditelluride reacts with tetra-tert-butyldiphosphane and tetra-isopropyldiphosphane (prepared from the corresponding chlorophosphanes with potassium in toluene) with formation of new tellurophosphinous acid esters p-CH3C6H4TePR2 (R = t-C4H9, i-C3H7). Distillation leads to pure yellow liquids that have been characterized by 1H-, 13C-, 31P-, and 125Te-NMR, by elemental analysis and by mass spectroscopy.  相似文献   
9.
Decomposition theorems for certain representations of Kac-Moody algebras which are needed for the construction of modular invariant unitary conformal models are proved. It is shown that allc<1 modular invariant models can then be recovered from gauged free fermionic models, including the exceptional cases.This work was supported in part by the Director, Office of Energy Research, Office of High Energy and Nuclear Physics, Division of High Energy Physics of the U.S. Department of Energy under Contract DE-AC03-76SF00098 and in part by the National Science Foundation under grant PHY85-15857Supported by the Swiss National Science FoundationSupported in part by the American-Israeli Binational Science Foundation and the Israeli Academy of Sciences  相似文献   
10.
It is very important to know the effective diffusivities of reactant gases through the porous solid matrices for a diffusion limited reaction. The single pellet high temperature diffusion cell reactor is used to measure the effective diffusivities of argon and nitrogen during the sequence of calcination, sintering, salt addition and sulfation of Greer limestone. This system can be used to study and gas—solid reaction systems where the solid phase undergoes changes between 25 and 1200°C.  相似文献   
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