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81.
The article is devoted to dimension functions of orthonormal wavelets on the real line with dyadic dilations. We describe properties of dimension functions and prove several characterization theorems. In addition, we provide a method of construction of dimension functions. Various new examples of dimension functions and orthonormal wavelets are included.  相似文献   
82.
This paper describes the synthesis of the first Ni(II) complexes with pyridoxal semicarbazone (PLSC), viz. Ni(PLSC)Cl2 · 3.5H2O (1), [Ni(PLSC)(H2O)3](NO3)2 (2), Ni(PLSC)(NCS)2 · 4H2O (3), [Ni(PLSC-2H)NH3] · 1.5H2O (4), as well as two new complexes with pyridoxal thiosemicarbazone (PLTSC), [Ni(PLTSC-H)py]NO3 (5) and [Ni(PLTSC-H)NCS] (6). Complexes 13 are paramagnetic and have most probably an octahedral structure, for complex 2 this was proved by X-ray diffraction analysis. In contrast, complexes 46 are diamagnetic and have a square-planar structure, and in the case of complex 5 this was also confirmed by X-ray structural analysis. In all cases the Schiff bases are coordinated as tridentate ligands with an ONX (X = O, PLSC; X = S, PLTSC) set of donor atoms. With the complexes involving the neutral form of PLSC and the monoanionic form of PLTSC, the PL moiety is in the form of a zwitterion. In addition to the above-mentioned techniques, all the complexes were characterized by measuring their molar conductivities, UV–Vis and partial IR spectra.  相似文献   
83.
Reaction of aqueous solutions of Ni(NO3)2 and pyridoxal semicarbazone (PLSC) in the presence of NaN3 afforded two complexes, viz. green, paramagnetic binuclear octahedral [Ni2(PLSC)21,1-N3)2(N3)2] · 2H2O (1) and, as admixture, red, octahedral [Ni(PLSC–H)2] · 2H2O (2) complex. Under the same reaction conditions, pyridoxal thiosemicarbazone (PLTSC) gave only one diamagnetic square-planar, red complex [Ni(PLTSC–H)N3] · H2O (3). In the absence of NaN3, the reaction of PLTSC and Ni(NO3)2 yielded brown paramagnetic octahedral complex [Ni(PLTSC)2](NO3)2 · H2O (4).  相似文献   
84.
Targeted tandem mass spectrometry (MS/MS) is an attractive proteomic approach that allows selective identification of peptides exhibiting abundance differences, e.g., between culture conditions and/or diseased states. Herein, we report on a targeted LC-MS/MS capability realized with a hybrid quadrupole-7 tesla Fourier transform ion cyclotron resonance (FTICR) mass spectrometer that provides data-dependent ion selection, accumulation, and dissociation external to the ICR trap, and a control software that directs intelligent MS/MS target selection based on LC elution time and m/z ratio. We show that the continuous on-the-fly alignment of the LC elution time during the targeted LC-MS/MS experiment, combined with the high mass resolution of FTICR MS, is crucial for accurate selection of targets, whereas high mass measurement accuracy MS/MS data facilitate unambiguous peptide identifications. Identification of a subset of differentially abundant proteins from Shewanella oneidensis grown under suboxic versus aerobic conditions demonstrates the feasibility of such approach.  相似文献   
85.
A series of eleven specially designed benzotriazole monoazo dyes for use in surface enhanced resonance Raman scattering studies are reported. Unlike previous benzotriazole dyes produced for SERRS, these dyes have been synthesised to be trifunctional in nature. The presence of the benzotriazole moiety provides surface complexing properties, the azo linkage provides the colour and hence extra sensitivity and the nucleophilic amine group enables further functionalisation.  相似文献   
86.
With a combination of experiment and theory (ab initio and DFT), we demonstrate that the Al(3+) cation can be stabilized in the gas phase using ligands, which have the ability to act as powerful sigma electron donors and electron acceptors. The latter property, which implies that electron density from the aluminum cation moves into ligand antibonding orbitals, has not previously been considered significant when accounting for the behavior of Al(3+). Of the three ligands identified as falling into the above category, acetonitrile appears to form the most stable complexes in the gas phase, which is in accord with the long established fact that solid-state complexes with Al(3+) are readily isolated. From the results, it is suggested that chain or ring compounds containing the -C triple bond N group might act as successful sequestering agents for Al(3+) from aqueous solutions.  相似文献   
87.
We present a simple method to obtain reliable ground-state entropies of Ising antiferromagnets in a maximum critical field. As an example, the ground-state entropy for the square lattice is established for allS. Both the case of the first-, and of the second-neighbour interactions are considered.  相似文献   
88.
Summary The acid-base properties of the -oxo bridged dimeric iron complexes [FeL]2O with the ligands based on S-alkyl-1,4-bis(substituted salicylidene)isothiosemicarbazide and a tetramer with S-methyl-1,4-bis(salicylidene)isothiosemicarbazide, {[FeL]2O}2I3·I2, were investigated by cyclic voltammetry at glassy carbon electrode inDMF. Studies were carried out in the presence of either a weak (phenol) or a strong (HClO4 aq.) acid. The stoichimoetry of the reaction, changes in the general voltammetric pattern and the electrode reaction mechanism were discussed. These studies served as the basis for three-electrode amperometric titrations to determine the content of several of these complexes.
Voltammetrische und titrimetrische Untersuchung der Säure-Base-Eigenschaften einiger -oxo dimerer Eisen(III)-Komplexe inDMF-Lösungen
Zusammenfassung Die Säure-Base-Eigenschaften einiger dimerer -oxo-Eisen(III)-Komplexe [FeL]2O mit Liganden auf Basis von 1,4-bis(substituierten Salicyliden)S-(alkyl)isothiosemicarbaziden sowie eines tetrameren Komplexes mit 1,4-Bis(salicyliden)S-methylisothiosemicarbazid, {[FeL]2O}2I3·I2, wurden mittels zyklischer Voltammetrie an der Glaskohlenstoffelektrode inDMF-Lösungen untersucht. Die Messungen wurden in Gegenwart entweder einer schwachen (Phenol) oder einer starken (HClO4 aq.) Säure ausgeführt. Die Stöchiometrie der Reaktion, die Änderungen der voltammetrischen Kurven und der Elektroden-Reaktionsmechanismus wurden diskutiert. Diese Untersuchungen stellten eine Basis für Drei-Elektroden amperometrische Titrationen dar, die für die Bestimmung des Gehalts einiger dieser Komplexe angewendet wurden.
  相似文献   
89.
In the recent book of R.S. Varga, [3], one of two main recurring themes is that a nonsingular theorem for matrices gives rise to an equivalent eigenvalue inclusion set in the complex plane, and conversely. If such nonsingularity result can be extended via irreducibility, usually this can be used for obtaining more information about the boundary of the corresponding eigenvalue inclusion set. Here we will start with one of Geršgorin‐type theorem for eigenvalue inclusion, given in [1], (for which exists corresponding equivalent statement about nonsingularity of a particular class of matrices) and use it for proving necessary conditions for an eigenvalue to lie on the boundary of localization area. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
90.
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