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The Random Walk Value for Ranking Spatial Characteristics in Road Networks
This study proposes a new network index at both nodal and link levels to rank the spatial characteristics of individual network components. The objective is to create a network metric that captures socioeconomic characteristics in urban environments. Because this index is based on the random walk simulation modeling strategy, it is coined the random walk value (RWV). An algorithm and an associ...


Monomeric, dimeric and polymeric lanthanide(III) complexes of a hexaazamacrocyclic imine derived from 2,6-diformylpyridine and ethylenediamine
A series of mononuclear Ln(III) complexes of a hexaaza Schiff base has been obtained in a template condensation reaction of 2,6-diformylpyridine, ethylenediamine and the appropriate lanthanide nitrate salt. The X-ray crystal structures of the Ce(III), Pr(III), Eu(III) and Y(III) complexes, recrystallized from water or methanol, have been determined. The reaction of the obtained complexes with h...
Novel chelate complexes of Co(II), Ni(II), Cu(II), Pd(II) derived from anti- and syn-isomers of 2-(2-aminothiazole-4-yl)-2-hydroxyiminoacetic acid with pro-/antiproliferative actions on endothelial cells
Anti- and syn-isomers of 2-(2-aminothiazole-4-yl)-2-hydroxyiminoacetic acid (anti-A and syn-A respectively) were used as potential biologically active polydentate complexing agent for Co2+, Ni2+, Cu2+ and Pd2+ ions for the synthesis of novel complex compounds with directed angiogenesis-correcting action. It shown that the location of functional groups in ligand molecules, the electronic structu...


New bis-o-semiquinonato cobalt complexes with 1,10-phenanthroline ligands
Two novel cobalt compounds [Co(1,10-phen)(4-OMe-3,6-DBSQ)2] (Complex 1) and [Co(2,9-Me2-1,10-phen)(3,6-DBSQ)2] (Complex 2) (1,10-phen – 1,10-phenanthroline, 2,9-Me2-1,10-phen – 2,9-dimethyl-1,10-phenanthroline; 3,6-DBSQ – 3,6-di-tert-butyl-benzoquinone-1,2, 4-OMe-3,6-DBSQ – 4-methoxy-3,6-di-tert-butyl-benzoquinone-1,2) were obtained and investigated by means of X-ray structural analysis...
On the reactions of chlorodithiophosphoric acid pyridiniumbetaine with polyfunctional nucleophiles. Part IV: Reactions with thiosemicarbazide monoaryl derivatives
In connection with our previous research, reactions of chlorodithiophosphoric acid pyridiniumbetaine, py. PS2Cl (I), with monoaryl thiosemicarbazide derivatives RN(H)C(S)N(H)NH2, (R=phenyl, 4-nitrophenyl) were studied with the aim to prepare new heterocyclic compounds. All reactions were carried out in acetonitrile in the presence of pyridine as an HCl acceptor. New compounds, pyridinium salts ...


Copper(II) complexes of Neb-colloostatin and of (P4A) analogue Stability Structure Apoptosis
The nineteenth amino acid peptide Neb-colloostatin SIVPLGLPVPIGPIVVGPR and its analogue with point mutation (P4A) were synthesized and their copper(II) complexes were studied by potentiometric, UV–Vis, circular dichroism (CD), and electron paramagnetic resonance (EPR) spectroscopic methods. The amine-N nitrogen atoms of serine residues were found to be the primary metal binding sites of both ...
Mono- and polynuclear vanadium(IV) and -(V) compounds with 2-substituted phenyl/pyridyl heterocyclic chelates
In this account, we report the isolation of novel vanadium(IV) and -(V) compounds with 2-substituted phenyl/pyridyl heterocyclic chelates. The 1:2molar reaction between NH4VO3 and 2-hydroxyphenylbenzothiazole (Hobs) led to the formation of a polynuclear vanadium(IV) compound, [VO(obs)2] n (1). A trigonal bipyramidal mononuclear complex, cis-[VO2(obz)py] was formed from the reaction of NH4VO3 a...

Electric properties and internal dynamics of the [C6H18N2] SbCl5 [C6H18N2] Cl2 in intermediate temperature phase (part II)
The electric conductivity of the [C6H18N2] SbCl5[C6H18N2] Cl2 crystals (abbreviated as DEDA) has been studied by means of impedance analysis in a high temperature regime. The results have been correlated with ones obtained by means of CW 1H NMR analysis and the crystal structure of [C6H18N2] SbCl5 [C6H18N2] Cl2. It was found that conductivity increases at the temperature which corresponds to th...
Exploration of the solid state metallosupramolecular chemistry of mononuclear nickel(II) complexes with α-hydroxycarboxylates and 2,2′-dipyridylamine
Six new nickel(II) complexes have been synthesized by the reaction of the nitrogen donor coligand 2,2′-dipyridylamine (dipyam) and three different α-hydroxyacids (H2L′) with different levels of bulkiness, namely lactic, 2-methyllactic and mandelic acids. Two types of compounds have been obtained: neutral complexes of formula [Ni(HL′)2(dipyam)] and the cationic metal complexes of general ...

A new redox-based approach for synthesizing a mixed-valence hybrid polymolybdate uncommonly bicapped by Cr(III) coordination complexes
The grafting of Cr(III) coordination complexes as capping units onto polyoxometalates (POMs), still remains a considerable synthetic challenge due to the difficulty in replacement of aqua-ligands in [Cr(H2O)6]3+ complexes. A new synthetic method was developed, from in situ reduced dichromate ions, to generate Cr(III) ions, which were designed to coordinate to organic ligands simultaneously, whi...
Bonding μ1,3- (trans) vs μ1,2- (cis) in squarato-bridging dinuclear copper(II) complexes derived from pyridyl amine ligands
A series of trans- and cis-dinuclear squarato-bridged copper(II) complexes [Cu2(dpya)4(μ1,3-C4O4)](ClO4)2·MeOH (1), [Cu2(bdmpzpy)2(μ1,3-C4O4)(H2O)2](ClO4)2·5H2O and [Cu2(pmea)2(μ1,2-C4O4)](ClO4)2·1.5H2O derived from di-, tri- and tetra-dentate pyridyl amine ligands (C4O4 2− is the 3,4-dihydroxycyclobut-3-en-1,2-dione dianion=squarate dianion, dpya=di-2-pyridylamine, bdmpzpy=2,6-bis[(2,5...

The effect of Brij® surfactants in sol–gel processing for the production of TiO2 thin films
Titanium dioxide thin films were deposited via a Brij® surfactant modified non-aqueous sol–gel method onto fluorine doped tin oxide glass substrates. The number of layers and surfactant concentration and type in the sols was varied. The as deposited films were annealed at a range of temperatures (500–600°C) and times (15–60min) before characterisation and photocatalytic testing. The ann...
Side-chain-modulated supramolecular assembly between CuX2 (X=Cl, Br) and quasi-planar π-conjugated organic synthons of 1, 3, 5-tris(2-alkylthiolpyrimidinyl)benzene: Crystal structures and conductive properties
A class of π-conjugated organic synthons, namely 1, 3, 5-tris(2-alkylthiolpyrimidinyl)benzene (TMPB: alkyl=Me; TEPB: alkyl=Et; TPPB: alkyl=n-Pr) was designed and prepared, which only differ in the length of linear side chain. It was found that these organic synthons can keep a quasi-planar conformation even coordinated to metal ions due to intramolecular C–H⋯N hydrogen bonds. assembly of t...
Structure and characterization of the phase transition of the new organic–inorganic hybrid compound
Bis(4-acetylanilinium) tetrachloridozincate has been synthesized and characterized by single-crystal X-ray diffraction at 298K and impedance spectroscopy. At room temperature, the title compound crystallized in the orthorhombic system (Cmca space group) with Z =8 and the following unit cell dimensions: a =19.4331Å, b =15.5209Å, c =13.7318Å. The structure consists of alternate organic and ino...
Donor-stabilized hypercoordinated silicon(IV) chelates with cyclohexylideneimino-N ligand group: Role of substituents on ionization
N-Cyclohexylideneimino-O-(trimethylsilyl)acylimidates react smoothly with XSiCl3 (X=Me, Ph, vinyl and Cl) in a transsilylation reaction producing ionic pentacoordinate bischelates and neutral hexacoordinated complexes depending on the electronic and steric behavior of the ligands. These hypercoordinated silicon complexes are characterized by UV–Vis, FT-IR and NMR spectroscopic techniques. A n...