Hasan Genç

Partly-refined chemical by-product gypsums as cement additives

Abstract The effects on the setting and mechanical properties of partly-refined boro- and phosphogypsum mixed with Portland and trass cements were studied and compared with a Portland cement containing high grade natural gypsum. It was found that the partly refined boro- and phosphogypsum can be used in place of natural gypsum for Portland and trass cements. Reasons for the observed properties of the Portland and trass cements containing the aforementioned chemical gypsum are concluded.

Utilization of borogypsum for cement

Borogypsum is a by-product of a boric acid factory. Approximately ninety thousand tons per year are produced by two boric acid factories in Turkey. The borogypsum consists primarily of CaSO4·2H2O, secondarily of B2O3, and some other impurities. In this work, the use of borogypsum as an additive in cement production was studied. For this, the proportion of B2O3 in borogypsum was gradually decreased by water extraction. Refined borogypsum was mixed with Portland and trass cements and its effects on the setting and mechanical properties of these mixes were studied. It was concluded that refined borogypsum can be used for Portland and trass cements.

Analysis of mixed-linked (1→3), (1→4)-β-d-glucans in cereal grains from Turkey

Abstract In this study, (1→3), (1→4)-β- d -glucan content of some culture type cereal grains grown in Turkey, such as barley, wheat, oats, rye, corn, beans, peas and chick peas; and barley, wheat (white, shain, lanser), rye, orabyehis sativa (adi yonca in Turkish) and medicaga satien (adi korunga in Turkish) grown in the plant research institute of the faculty of Ataturk University in Erzurum (Turkey) were determined quantitatively by enzymatic methods. By using pure β- d -glucanase and β- d -glucosidase in the experiments, (1→3), (1→4)-glycosidic bonds of linear polysaccharides found in cell-wall endosperm of plant seeds were hydrolyzed and the resulting β- d -glucans were determined by glucose oxidase/peroxidase solution and measuring the absorbances at 510 nm in a UV-spectrophotometer. The β- d -glucan levels of cultured cereal grains were compared to those obtained from other countries. Mean whole grain β-glucan levels (dry weight basis) for each grain type analyzed in this study were barley, 3.6%, oats, 4.1%, rye, 1.4% and wheat, 0.8%, corns (I, II), 1.4%, 0.5%, beans (I, II) 2.9%, 2.8%, peas (I, II), 0.9% and 1.4% and chickpeas, 0.9%. β- d -Glucan levels of each grain type grown in the Plant Research Institute of Ataturk University analyzed in this study were: barley, 2.8%, rye, 0.9%, wheats (shain, white, lanser), 5.4%, 0.5%, 0.6%, Orabyehis sativa , 1.4%, and Medicaga satien , 1.1%.

The Synthesis, Characterization, Crystal Structure and Photophysical Properties of a New Meso-BODIPY Substituted Phthalonitrile.

A new highly fluorescent difluoroboradipyrromethene (BODIPY) dye (4) bearing an phthalonitrile group at meso-position of the chromophoric core has been synthesized starting from 4-(4-meso-dipyrromethene-phenoxy)phthalonitrile (3) which was prepared by the oxidation of 4-(2-meso-dipyrromethane-phenoxy)phthalonitrile (2). The structural, electronic and photophysical properties of the prepared dye molecule were investigated. The final product exhibit noticeable spectroscopic properties which were examined by its absorption and fluorescence spectra. The original compounds prepared in the reaction pathway were characterized by the combination of FT-IR, 1H and 13C NMR, UV–vis and MS spectral data. It has been calculated; molecular structure, vibrational frequencies, 1H and 13C NMR chemical shifts and HOMO and LUMO energies of the title compound by using B3LYP method with 6-311++G(dp) basis set, as well. The final product (4) was obtained as single crystal which crystallized in the triclinic space group P-1 with a = 9.0490 (8) Å, b = 10.5555 (9) Å, c = 11.7650 (9) Å, α = 77.024 (6)°, β = 74.437 (6)°, γ = 65.211 (6)° and Z = 2. The crystal structure has intermolecular C—H···F weak hydrogen bonds. The singlet oxygen generation ability of the dye (4) was also investigated in different solvents to determine of using in photodynamic therapy (PDT).

A triterpenoid saponin from Cyclamen coum.

A new triterpenoid saponin, coumoside A, has been isolated from the whole plant of Cyclamen coum and the structure of this novel saponin (C58H92O27) has been deduced by NMR methods based on 1H, 13C, DEPT, 1H-1H COSY, HETCOR, NOESY-NMR experiments and the FAB-mass spectrum. It has the structure 3 beta-O-[beta-D-glucopyranosyl-(1-6)-[alpha-L-arabinopyranosyl- (1-2)]-beta-D-glucopyranosyl-(1-4)-[beta-D-glucopyranosyl-(1-2)]-alpha-L -arabinopyranosyl]-16 alpha-hydroxy-30,28 beta-lactone-olean-12-ene and is called coumoside.