Breakdown of the resistor-network model for steady-state hopping conduction

Master equations are used to study steady-state hopping in a disordered solid. We express each site's occupancy in terms of its quasi-electrochemical potential (QECP); currents flow between sites whose QECP's differ. Coupled nonlinear circuit equations result from the steady-state condition and a boundary condition. When site-to-site QECP differences are much smaller than the thermal energyk _B T, the effect of current flow on occupancies is ignorable, and the equations reduce to those of a resistance network. But this resistor-network model fails: a) at low temperatures, b) with increasing disorder, and c) with increasing emf. We therefore study hopping conduction beyond this approximation. Exactly soluble examples show the importance of current-induced charge redistribution in non-ohmic steady-state flow.     

Quinoxalinium Dichromate: A Newand Efficient Reagent for the Oxidation of Organic Substrates

Summary.  A new chromium(VI) reagent, quinoxalinium dichromate ([C₈H₆N₂H]₂Cr₂O₇, QxDC), was prepared by reacting quinoxaline with CrO₃ in water. QxDC oxidizes primary and secondary alcohols and oximes to the corresponding carbonyl compounds, and anthracene to anthraquinone. Corresponding author. E-mail: beytiyeozgun@hotmail.com Received February 2, 2002; accepted April 3, 2002     

Thermodynamic analysis and multi-objective optimization performance of solid oxide fuel cell–Ericsson heat engine–reverse osmosis desalination

Journal of Thermal Analysis and Calorimetry - This paper targets to consider a hybrid cycle consisting of a solid oxide fuel cell and an Ericsson thermal engine that provides drinking water by...     

Synthesis and Characterization of a New (E,E)-Dioxime and its Homonuclear Complexes

N′-(4′-Benzo[15-crown-5]naphthylaminoglyoxime (H₂L) and its sodium chloride complex (H₂L·NaCl) have been prepared from 2-naphthylchloroglyoxime, 4′-aminobenzo[15-crown-5] and sodium bicarbonate or sodium bicarbonate and sodium chloride. Nickel(II), cobalt(II) and copper(II) complexes of H₂L and H₂L·NaCl have a metal–ligand ratio of 1:2 and the ligand coordinates through the two N atoms, as do most of the vic-dioximes. The BF ₂ ⁺ -capped Ni(II), Co(III) and mononuclear complexes of thevic-dioxime were prepared. The macrocyclic ligands and their transition metal complexes have been characterized on the basis of IR, ¹H NMR spectroscopy and elemental analyses data.     

Synthesis and Characterization of a New (E,E)-Dioxime and its Homonuclear Complexes

N′-(4′-Benzo[15-crown-5]naphthylaminoglyoxime (H₂L) and its sodium chloride complex (H₂L·NaCl) have been prepared from 2-naphthylchloroglyoxime, 4′-aminobenzo[15-crown-5] and sodium bicarbonate or sodium bicarbonate and sodium chloride. Nickel(II), cobalt(II) and copper(II) complexes of H₂L and H₂L·NaCl have a metal–ligand ratio of 1:2 and the ligand coordinates through the two N atoms, as do most of the vic-dioximes. The BF₂⁺-capped Ni(II), Co(III) and mononuclear complexes of thevic-dioxime were prepared. The macrocyclic ligands and their transition metal complexes have been characterized on the basis of IR, ¹H NMR spectroscopy and elemental analyses data.     

Synthesis of pyrimidine Schiff base transition metal complexes: characterization,spectral and electrochemical analyses,and photoluminescence properties

Research on Chemical Intermediates - This study includes the synthesis, characterization, electrochemical analysis and photoluminescence properties of a Schiff base ligand bearing a pyrimidine ring...     

Synthesis and Spectroscopic Characterization of Group 6 Pentacarbonyl(4-substituted pyridine)metal(0) Complexes

Carbonyl-metal (M:Cr, Mo, W) derivatives of 4-substituted pyridines [4-methylpyridine (4-mp), 4-tert-butylpyridine (4-tbp) and 4-dimethylaminopyridine (4-dmap)] where the metal center is bonded to the nitrogen atom of the substituted pyridine ring are described. The organometallic complexes, M(CO)₅L, were synthesized by either the direct reaction of the metal hexacarbonyls or by the thermal substitution of M(CO)₅(THF) with the pyridine ligands; 4-methylpyridine (1), 4-tert-butylpyridine (2), 4-dimethylaminopyridine (3). The reported complexes were purified by column chromatography and recrystallization. The complexes were all characterized in solution by elemental analysis, MS, ir , ¹H-nmr and ¹³C-nmr spectroscopies.     

Investigation of therapeutic efficiency of phenytoin (PHT) labeled with radioactive 131I in the cancer cell lines

The aim of this study is to determine the incorporations of PHT radiolabeled with ¹³¹I (¹³¹I-PHT) on U-87 MG, Daoy and A549 cancerous cell lines. For this, cold and radio-labeling studies were carried out. The radio-labeling yield of ¹³¹I-PHT was obtained about 95 %. Subsequently, cell culture studies were carried out and radio-labeling yields of ¹³¹I, ¹³¹I-PHT on U-87 MG, Daoy and A549 cancerous cells were investigated. Cell culture studies demonstrated that the incorporation values of ¹³¹I-PHT on the three cell lines decreased with increasing radioactivity. Consequently, ¹³¹I-PHT may be a good radiopharmaceutical for targeting radionuclide therapy of Central Nervous System Tumors.     

New palladium(II)–N‐heterocyclic carbene complexes containing benzimidazole‐2‐ylidene ligand derived from menthol: synthesis,characterization and catalytic activities

A new series of sterically hindered ligands containing (1R,2S,4R)‐(+)‐menthoxymethyl group attached to benzimidazole‐based N‐heterocyclic carbene (NHC), palladium–bis‐NHC complexes and (κ²‐C,N)‐palladacyclic NHC complexes have been synthesized and characterized using appropriate spectroscopic techniques. Catalytic performance of the palladium complexes has been investigated for allylic alkylation, Suzuki and Heck carbon–carbon coupling reactions. These complexes smoothly catalyse the carbon–carbon bond formation reactions. Copyright © 2016 John Wiley & Sons, Ltd.