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101.
Leila Moura Mark Gilmore Samantha K. Callear Tristan G. A. Youngs 《Molecular physics》2019,117(22):3364-3375
102.
103.
104.
Mohammad Hakimi Reza Takjoo Vahideh Erfaniyan Esther Schuh Fabian Mohr 《Transition Metal Chemistry》2010,35(8):959-965
Two complexes of a thiosemicarbazone ligand, namely N-(2-hydroxyethyl)-2-(thiophene-2-ylmethylene)-hydrazinecarbothioamide (HL), have been synthesized. The complexes have been
characterized by physico-chemical and spectroscopic methods. The crystal and molecular structures of [CoL3]·2MeOH (1) and [NiL2] (2) have been determined by X-ray diffraction studies. For both complexes, the metal is coordinated through the sulfur and azomethine
nitrogen atoms of the thiosemicarbazone. The ligand exists in its thiolate tautomeric form, and the central Co(III) and Ni(II)
atoms have distorted octahedral and square planar geometries, respectively, with five-membered chelate rings formed by the
ligand. The lattice of 1 shows infinite oxygen donor/acceptor hydrogen bonds in the ab plane and weak interactions between rings along the c axis, respectively, giving a supramolecular network. The molecular units in 2 are linked together by hydrogen bonds between the hydroxyl oxygen and hydrazone N proton, giving rise to an infinite ribbon
extended along the c-axis. These chains are connected by N3–H3···O1 interactions that form a sheet within the ac plane. 相似文献
105.
106.
We show that for any positive integer k?4, if R is a (2k-1)×(2k-1) partial Latin square, then R is avoidable given that R contains an empty row, thus extending a theorem of Chetwynd and Rhodes. We also present the idea of avoidability in the setting of partial r-multi Latin squares, and give some partial fillings which are avoidable. In particular, we show that if R contains at most nr/2 symbols and if there is an n×n Latin square L such that δn of the symbols in L cover the filled cells in R where 0<δ<1, then R is avoidable provided r is large enough. 相似文献
107.
Dr. Tristan Doussineau Dr. Anja Schulz Dr. Alejandro Lapresta‐Fernandez Dr. Artur Moro Dr. Susanne Körsten Dr. Sabine Trupp Dr. Gerhard J. Mohr 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(34):10290-10299
Advances in nanoparticle technology have recently offered new tools to the bioanalytical field of research. In particular, new nanoparticle‐based sensors have appeared able to give quantitative information about different species (ions, metabolites, biomolecules) in biosamples through ratiometric measurements. This article describes the methodologies developed so far in the design of such nanosensors. In particular, the different approaches to immobilize fluorescent chemosensor dyes to nanoparticles are presented. Concept designs of ratiometric nanosensors in terms of composition and architecture are also described and illustrated with examples taken from the literature. 相似文献
108.
Heinrich Puff Heide Hevendehl Kornelia Höfer Hans Reuter Willi Schuh 《Journal of organometallic chemistry》1985,287(2):163-178
The di-t-butyltin hydroxide halides t-Bu2Sn(OH)X (X = F, Cl or Br) have been prepared starting from the dihalides t-Bu2SnX2 or the oxide (t-Bu2SnO)3. X-Ray analysis of the three compounds shows dimeric molecules: two 5-coordinated tin atoms and the oxygen atoms of the hydroxyl groups are linked to a four-membered ring. As confirmed by the IR spectra, the molecules in the crystal are held together by OH?X hydrogen bonds. These are strong in the hydroxide fluoride but are weak in the analogous chloride and bromide. 相似文献
109.
Compound 2 was rearranged on treatment with 2N NaOH to the 2-benzazepine-3-propanoic 1 See footnote (5) of the preceding paper. acid 3 . Some aspects of the chemistry of this acid were studied. 相似文献
110.
The benzazepin-2-ones 7 and 9 were prepared from homoveratroyl chloride (4) and phenacylamine. Compounds 7 and 9 were used for the preparation of the benzazepin-2-amines 3, 11, 13 and 14. A synthesis of the benzazepine-1,2-dione 17 and the benzazepine-2,4-dione 20 is also described. 相似文献