über Metallkomplexe der Heteroarylformazane

Two new heteroarylformazans with two complex forming carboxy groups in the ortho position relative to the formazan chain have been synthesized. These compounds form complexes with uranyl, cobalt and nickel ions. The ratio metal/formazan of these complexes has been investigated.     

Reductive metallation of 6-methyl-2,3-diphenylquinoxaline. Synthesis of 1,4-dihydro-1,4-diazine derivatives

The reductive metallation of 6-methyl-2,3-diphenylquinoxaline 1 with sodium metal in tetrahydrofuran and inert atmosphere to a monomeric dianion 2 has been explored and the nucleophilicity of this disodium adduct was investigated with various alkylation and acylation reagents. An annulation of the pyrazine ring system was accomplished by treating the dianion with polymethylene chlorides, Cl(CH₂)_nCl, n = 3,4.     

Surface properties and wetting characteristics of liquid Ag–Bi–Sn alloys

Abstract  

Surface tension and density measurements of liquid Ag–Bi–Sn alloys were carried out over a wide temperature range using the sessile drop method. The experimental data of surface tension were analyzed by the Butler thermodynamic model in the regular solution approximation. The Sn-rich Ag–Bi–Sn liquid alloys show better wetting behavior on the Cu substrates as compared to the Ni substrates.     

The Cu and Te coordination environments in Cu-doped Ge–Te glasses

The structure of Ge₂₀Te₈₀, Ge₁₅Cu₈Te₇₇ and Ge₁₅Cu₅Te₈₀ glasses was investigated by diffraction techniques and extended X-ray absorption fine structure measurements. Large structural models were generated by fitting experimental data by the reverse Monte Carlo simulation technique. In Ge₂₀Te₈₀ glass, both Ge and Te obey the 8−N rule, and the structure is built up of GeTe₄ tetrahedra connected via Te–Te bonding or shared Te atoms connected to two Ge atoms. The coordination number of Te is significantly higher than 2 in Ge₁₅Cu₈Te₇₇. The average coordination number of Cu is 3.41±1 in this alloy. In Ge₁₅Cu₅Te₈₀ glass, Cu binds mostly to Te, while Cu–Cu bonding is significant in Ge₁₅Cu₈Te₇₇.     

Über Kobalt- und Nickelkomplexe der heterocyclisch substituierten Azomethine

The cobalt and nickel complexes of some heterocyclic substituted azomethins have been synthesized. Metal/azomethine ratio of these complexes has been studied.

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Teil der Dissertation,. Kaban, Univ. Istanbul 1975.     

Radiation-modified structure of Ge25Sb15S60 and Ge35Sb5S60 glasses

Atomic structures of Ge(25)Sb(15)S(60) and Ge(35)Sb(5)S(60) glasses are investigated in the gamma-irradiated and annealed after gamma-irradiation states by means of high-energy synchrotron x-ray diffraction technique. The first sharp diffraction peak (FSDP) is detected at around 1.1 A(-1) in the structure factors of both alloys studied. The FSDP position is found to be stable for radiation/annealing treatment of the samples, while the FSDP intensity shows some changes between gamma-irradiated and annealed states. The peaks in the pair distribution functions observed between 2 and 4 A are related to the Ge-S, Ge-Sb, and Sb-Sb first neighbor correlations and Ge-Ge second neighbor correlations in the edge-shared GeS(42) tetrahedra, and S-S and/or Ge-Ge second neighbor correlations in the corner-shared GeS(42) tetrahedra. Three mechanisms of the radiation-/annealing-induced changes are discussed in the framework of coordination topological defect formation and bond-free solid angle concepts.     

Synthesis of hetaryl‐substituted benzoxazoles via oxidative cyclization of phenolic schiff's bases

2‐(1H‐Pyrrol‐2‐yl)benzo[d]oxazoles, 4‐(benzo[d]oxazol‐2‐yl)quinoline and 2‐(benzo[d]oxazol‐2‐yl)‐4,6‐dimethylquinolines were obtained in good yield by the oxidative intramolecular ring closing reactions of phenolic Schiff's bases with the effect of manganese triacetate.     

Crystallization kinetics study of melt-spun Zr66.7Ni33.3 amorphous alloy by electrical resistivity measurements

In this paper, the electronic transport properties of as-spun Zr_66.7Ni_33.3 alloys were studied in detail by a combination of electrical resistivity and absolute thermoelectric power measurements over a temperature range from 25 up to 400 °C. Moreover, the isochronal and isothermal crystallization kinetics of Zr_66.7Ni_33.3 glassy alloy has been investigated based on the electrical resistivity measurements. The comparative study of the crystallization kinetics of these binary amorphous alloys was carried out, for the first time to our knowledge, using an accurate method for electrical resistivity measurements. In the isochronal heating process, the apparent activation energy for crystallization was determined to be, respectively, 371.4 kJ mol⁻¹ and 382.2 kJ mol⁻¹, by means of Kissinger and Ozawa methods. The Johnson–Mehl–Avrami model was used to describe the isothermal transformation kinetics, and the local Avrami exponent has been determined in the range from 2.97 to 3.23 with an average value of 3.1, implying a mainly diffusion-controlled three-dimensional growth with an increasing nucleation rate. Based on an Arrhenius relationship, the local activation energy was analyzed, which yields an average value E_x = 376.2 kJ mol⁻¹.

     

Über Metallkomplexe der Heteroarylformazane

Two new heteroarylformazans with two complex forming carboxy groups in the ortho position relative to the formazan chain have been synthesized. These compounds form complexes with uranyl, cobalt and nickel ions. The ratio metal/formazan of these complexes has been investigated.

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Teil der Dissertation,. Kaban, Univ. Istanbul 1975.