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WOS: 000250937000017, The enantioselective hydrolysis of racemic naproxen methyl ester by Candida rugosa lipase (CRL) was studied in aqueous buffer solution/isooctane reaction system in the presence of supercritical CO2. The effects pressure (75-160 bar), temperature (32-42 degrees C ) and reaction time (0.5-12 h) on the enantiomeric excesses of the product (ee(p)) and the substrate (ee(s)), enantiomeric ratio (E), conversion (x) and enzyme activity were investigated in a batch reactor system. The highest enantiomeric ratio achieved at 120 bar of pressure, 37 C of temperature and 2 h of reaction time was E= 193 with x=41.3%, ee(p)=97.9% and ee(s)=68.8%. CRL remained active at least for 12h at 37 degrees C and 120 bar in supercritical CO2 medium. Furthermore. enantiomeric ratio increased with increasing reaction time and reached the value of E=236 with ee(p) =98.2%, ee(s) =70.0% and x=41.6% after 12 h of hydrolysis. (C) 2007 Elsevier B.V. All rights reserved.

WOS: 000249494700014, PubMed ID: 17141939, For a pilot-scale application, pH control in the treatment of highly contaminated dye industrial wastewater containing metallic compounds as the main pollutants has been investigated with a method using adaptive heuristic criticism control (AHCC). Subsequent experimentation on between 12 and 181 of the wastewater was carried out using statistical experimental design methodology to evaluate the effects of three critical factors: slaked lime (calcium hydroxide, Ca(OH)(2)) concentration, iron chloride (FeCl3) concentration and wastewater volume. With these critical factors, the wastewater treatment process is modeled as an appropriate quadratic cost function of the turbidity of the clarified water. The model is optimized with Rosenbrock's method. Response surface topology of the wastewater treatment is given in terms of optimal concentrations of lime water and FeCl3 and optimal wastewater volume at pH 11. (c) 2006 Elsevier Ltd. All rights reserved.

WOS: 000242642500002, Supercritical fluid desorption has been carried out in a fixed bed column to desorp nitrophenolic compounds from organically modified bentonite. The experiments were carried out in the sequence of synthesis of organobentonite (HDTMA-B) and then adsorption of phenolic compounds to organobentonite in aqueous solutions, desorption of phenolic compounds from organobentonite using supercritical fluids (SCFs) and adsorption of nitrophenols to regenerated organobentonite. The desorption parameters such as pressure (20-40 MPa), temperature (40-100 degrees C) and co-solvent concentration (2.5-20 vol.%) were investigated at 2 ml/min flow rate. While the desorption yield of o-nitrophenol (oNP) was 93 wt.% using supercritical CO2 (SC CO2) by operating at 20 MPa, 40 degrees C, 2 ml CO2/min in 2 h of desorption, the desorption yields of M-nitrophenol (mNP) and p-nitrophenol (pNP) reached up to 71.8 wt.% (at 20 MPa, 60 degrees C using 7.5 vol.% ethanol) and 50 wt.% (at 40 MPa, 60 degrees C, 10 vol.% ethanol), respectively. In addition, the results showed that the regenerated HDTMA-bentonite toward nitrophenols exhibited changing adsorption capacity after several regeneration cycles. It was therefore concluded that exhausted/used organobentonites might be regenerated via processes involving supercritical fluid extraction. (C) 2006 Elsevier B.V. All rights reserved.

WOS: 000241170800005, The generalized delta rule (GDR) algorithm with generalized predictive control (GPC) control was implemented experimentally to track the temperature on a set point in a batch, jacketed polymerization reactor. An equation for optimal temperature was obtained by using co-state Hamiltonian and model equations. To track the calculated optimal temperature profiles, controller used should act smoothly and precisely as much as possible. Experimental application was achieved to obtain the desired comparison. In the design of this control system, the reactor filled with styrene-toluene mixture is considered as a heat exchanger. When the reactor is heated by means of an immersed heater, cooling water is passed through the reactor-cooling jacket. So the cooling water absorbs the heat given out by the heater. If this is taken into consideration, this reactor can be considered to be continuous in terms of energy. When such a mixing chamber was used as a polymer reactor with defined values of heat input and cooling flow rate, system can reach the steady-state condition. The heat released during the reaction was accepted as a disturbance for the heat exchanger. Heat input from the immersed heater is chosen as a manipulated variable. The neural network model based on the relation between the reactor temperature and heat input to the reactor is used. The performance results of GDR with GPC were compared with the results obtained by using nonlinear GPC with NARMAX model. The reactor temperature closely follows the optimal trajectory. And then molecular weight, experimental conversion and chain lengths are obtained for GDR with GPC. (c) 2006 Elsevier Ltd. All rights reserved.

Kaya, Murat ( Aksaray, Yazar ), Chitosan samples from two mushroom species (Boletus bovinus, Laccaria laccata) were obtained and characterized by viscosimetry, attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), elemental analyses (EA), nuclear magnetic resonance spectroscopy (13C NMR), X-ray diffraction (XRD) and thermogravimetric (TGA) analyses. Properties of the fungal chitosan samples were compared to commercial low-molecular weight chitosan, crustacean chitosan (Cervimunida johni) and chitosan obtained from an insect (Hilobius abietis). Additionally, the cytotoxic properties of chitosan in vitro on cancerous hepatoma and non-cancerous ovary cells cultivated on films with different chitosan concentrations was evaluated. As a conclusion, this study clearly revealed that low-molecular weight chitosan films and solutions with high degree of deacetylation can act cytotoxically on both tumor MH-22A and normal CHO cells in vitro. Consequently, this work may be useful for further investigations of natural anticancer products in medical areas.

WOS: 000425719800013, The synthesis of two known unsymmetrical N-capped tripodal amines, 3-((2-aminoethyl)(pyridin-2-ylmethyl)amino)propan-1-ol (3) and 3-((3-aminopropyl)(pyridin-2-ylmethyl)amino)propan-1-ol (4) is reported. They feature a longer 3-hydroxypropyl arm than in previously employed analogues (2-hydroxyethyl and ethylamino arms or 2-hydroxyethyl and propylamino arms in 1 and 2, respectively). Both of these tripodal amines, 3 and 4, are equipped with a 2-methylpyridyl-arm, a 3-hydroxypropyl arm and either an ethylamino-arm (3) or a propylamino-arm (4). The amines, 3 and 4, have been employed in one pot condensation reactions with salicylaldehyde and its derivative in the presence of zinc salts to generate a series of new mononuclear complexes, [ZnLaldi(Cl)] or [ZnLaldi](BF4). The complexes obtained here aren't exhibit arm-length dependence. The reactivity of the ligands with zinc chloride and zinc bis (tetrafluoroborate) depends on the anion present. Ligand L-2 reacts with Zn(BF4)(2) to form the five coordinated complex [(ZnL2)-L-II](BF4), while the reaction of L-1, L-3 and L-4 with ZnCl2 yields the mononuclear five coordinated complexes [(ZnLaldi)-L-II(Cl)] with an uncoordinated alcohol donor group. X-ray crystal structure determinations of [ZnL1(Cl)], [ZnL4(Cl)] and [ZnL2](BF4) confirmed they are mononuclear. The Zn(II) ion in [ZnL4(Cl)] is in a distorted square pyramidal environment whilst Zn(II) is almost exactly between square pyramidal and trigonal bipyramidal distorted geometry in [ZnL1(Cl)] CH3OH and [ZnL2](BF4). Computational investigations of studied complexes are performed at B3LYP/6-31G (d,p) (LANL2DZ) in vacuum. (C) 2017 Published by Elsevier B.V., Faculty of Chemistry, Bu-Ali Sina University; Otago University; MacDiarmid Institute for Advanced Materials and Nanotechnology, The authors acknowledge the Faculty of Chemistry, Bu-Ali Sina University, the Otago University and the MacDiarmid Institute for Advanced Materials and Nanotechnology for financial support and Professor Sally Brooker for hosting MS for a 6-month research visit. Also, this research is made possible by TUBITAK ULAKBIM, High Performance and Grid Computing Centre (TR-Grid e-Infrastructure), Turkey.

WOS: 000413387400014, Two new copper(II) and nickel(II) complexes [M(NC-C6H4COO)2(C6H6N2O)(2)(H20)(2)] (where M:Cu and Ni) have been synthesized and characterized by elemental analysis, FT-IR and UV Vis spectroscopy, spectroscopic ellipsometer (SE), X-ray crystallography, thermal analysis and molar conductivity. X-ray measurements showed that both of the complexes crystallized in triclinic system with the space group P-1. The isostructure complexes have distorted octahedral geometry around the metal atom center. In both of the crystal structures, the metal atoms are coordinated by two nitrogen atoms from two different nicotinamide ligands, two carboxyl oxygen atoms from two different 4-cyanobenzoate anions and two oxygen atoms from two different water molecules. From the linear absorption spectra and spectroscopic ellipsometer measurements, it was observed that these complexes showed different optical behaviors. (C) 2017 Elsevier B.V. All rights reserved., Kafkas University Research Fund [2016-FM-49], The authors thank the Kafkas University Research Fund for financial support under Grant No. 2016-FM-49.

WOS: 000384385200008, This study investigates the application of fuzzy regression to the viscometric analysis of polymer-polymer miscibility by using experimental viscosity data for polystyrene (PS), poly(styrene-co-acrylonitrile) (PSAN) and PS/PSAN blends in CHCI3 and DMF at different temperatures. The first stage includes the calculations of the fuzzy thermodynamic interaction parameter based on the results from the fuzzy regression models. In the second stage, the possibility and necessity measure-dependent results of the immiscibility (or miscibility) are presented and compared with the traditional miscibility estimations. This study shows that the fuzzification of traditional regression as well as the decision making on miscibility may have a good potential to be used for viscometric studies. (C) 2016 Elsevier B.V. All rights reserved.

International audience; This study demonstrates the coupling of Ionic liquids (ILs) with a membrane contactor for post-combustion CO2 capture at moderate pressures and temperatures. ILs 1-ethyl-3-methylimidazolium methyl sulfate([emim][MeSO4]), 1-ethyl-3-methylimidazolium dicyanamide([emim][DCA]), 1-ethyl-3-methylimidazolium ethyl sulfate([emim][EtSO4]) and 1-ethyl-3-methylimidazolium acetate ([emim][AC]) were selected due to their high thermal stability, moderate viscosity and surface tension, as well as high CO2 solubility. No wetting conditions were confirmed for the polypropylene membrane by measuring contact angle, liquid entry pressure (LEP) and SEM of fiber surface before and after the operation. ILs were recirculated in the setup until reaching pseudo-steady-state. All four ILs were able to capture a substantial amount of CO2 during the specified operation time. Initially, very high values of CO2 mass transfer flux and experimental overall mass transfer coefficient were obtained which further decreased with operation time and reached a nearly constant value at pseudo-steady-state. Effect of CO2 loading of the ILs and temperature on enhancement factor and first order rate constant were evaluated. The absorption behavior and kinetics were strongly influenced by the CO2 concentration in the ILs, which divides the absorption process in two steps; an initial faster absorption at the gas-liquid interface and later slower absorption in the bulk of the IL. Finally, a pseudo-steady-state modelling approach was implemented and validated.

WOS: 000370104700020, The process of mono and binary removal of crystal violet and safranin dyes by Spirulina sp. (blue-green algae) modified with cationic surfactant is evaluated. The surfactant used was hexadecyltrimethylammonium bromide (HDTMA). Spirulina sp. was cultivated in Zarrouk's medium. The adsorptive properties of the modified Spirulina sp. (HDTMA-algae) were tested as a function of pH (2-10), contact time (5-180 min), temperature (25-45 degrees C, and initial dye concentrations (25-300 mg/L) and characterized with FTIR, SEM, EDX, XRD and BET analyses. The specific surface area of HDTMA-algae was 0.1990 m(2)/g. The data were fitted to non-linear Langmuir, Freundlich, and Dubinin-Radushkevich (D-R) isotherm models and non linear pseudo-first-order and pseudo-second-order kinetic models. The adsorption was 75% and 88% at pH 2 for Crystal Violet and Safranin dye, respectively. The maximum adsorption capacities were 101.87 mg/g and 54.05 mg/g and the k(F) values were 0.96 L/g and 3.56 L/g for Crystal Violet and Safranin, respectively. The kinetics of Crystal Violet and Safranin dyes onto HDTMA-algae were best described by the pseudo-second-order kinetic model. The negative values of free energy and enthalpy change indicated the feasibility, spontaneity, and exothermic nature of the adsorption process. Also, binary adsorption of Crystal Violet and Safranin dyes onto HDTMA-algae from binary dye mixtures is compared. (C) 2015 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

WOS: 000368219600002, This study investigates the possibility of applying genetic programming to the stability assessment of rubble-mound breakwaters. The genetic programming algorithm is employed to develop various explicit models to predict the stability number of armor blocks. The genetic programming models are trained and tested using the experimental data of Van Der Meer (1988). The results show that the genetic programming based models have better predictive performances than Van der Meer's stability equations, and that genetic programming has good potential for solving complex problems in the field of coastal engineering. (C) 2015 Elsevier Ltd. All rights reserved.

WOS: 000389770300045 In this study, praseodymium barium cobalt oxide nanofiber interfacial layer was sandwiched between Au and n-Si. Frequency and voltage dependence of epsilon', epsilon', tan delta, electric modulus (M' and M '') and sigma(ac) of PrBaCoO nanofiber capacitor have been investigated by using impedance spectroscopy method. The obtained experimental results show that the values of epsilon', epsilon', tand, M', M '' and sigma(ac) of the PrBaCoO nanofiber capacitor are strongly dependent on frequency of applied bias voltage. The values of epsilon', epsilon '' and tand show a steep decrease with increasing frequency for each forward bias voltage, whereas the values of sigma(ac) and the electric modulus increase with increasing frequency. The high dispersion in epsilon' and epsilon '' values at low frequencies may be attributed to the Maxwell-Wagner and space charge polarization. The high values of epsilon' may be due to the interfacial effects within the material, PrBaCoO nanofibers interfacial layer and electron effect. The values of M ' and M '' reach a maximum constant value corresponding to M-infinity approximate to 1/epsilon(infinity) due to the relaxation process at high frequencies, but both the values of M ' and M '' approach almost to zero at low frequencies. The changes in the dielectric and electrical properties with frequency can be also attributed to the existence of N-ss and R-s of the capacitors. As a result, the change in the epsilon', epsilon '', tan delta, M', M '' and ac electric conductivity (sigma(ac)) is a result of restructuring and reordering of charges at the PrBaCoO/n-Si interface under an external electric field or voltage and interface polarization. (C) 2016 The Authors. Published by Elsevier B.V.

WOS: 000358635100003, Synthesized hydroxyapatite/clay (HA-C) and hydroxyapatite/pumice (HA-P) composites were used for tetracycline (TC) uptake studies from aqueous solution and their uptake capacities were compared. HA-C and HA-P composites were synthesized by precipitation method and the structures of the synthesized composites were characterized by XRD, SEM and BET analyses. Cation exchange capacities of HA-C and HA-P were found to be 84 meq/100 g and 33 meq/100 g, respectively. The TC adsorption using HA-C and HA-P was studied on batch mode. Various parameters such as contact time, solution pH, initial TC concentration, composite dosage, salinity and temperature were optimized. Langmuir, Freundlich and Dubinin-Radushkevich (D-R) isotherm models were applied to the equilibrium data. The maximum adsorption capacity onto HA-C was found to be 76.02 mg/g and about four times larger than the adsorption capacity of the HA-P (17.87 mg/g). The results indicated that the TC uptake onto HA-C and HA-P composites is mainly by a surface complexation and ion-exchange mechanism which depend on the solution pH. The calculated values of thermodynamic parameters indicated that the TC adsorption is favorable, physicochemical in nature. The sorption process follows pseudo-second-order and intraparticle diffusion kinetic models. The TC adsorption mechanism by HA-C and HA-P has been proposed. (C) 2015 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

WOS: 000355127300031, A new macrocyclic Schiff-base ligand, L, was synthesized by condensation reaction of 1,4-bis(2-formylphenyl) homopiperazine and 1,3-diaminopropane in acetonitrile. The Schiff-base ligand was characterized by using elemental analyses, IR, and mass spectroscopic techniques. Four new Ni(II), Cu(II), Co(II) and Zn(II) complexes of ligand, [NiLCl]ClO4, [CuLCl](ClO4), [CoLCl]ClO4 and [ZnLCl]ClO4 were prepared and characterized by elemental analyses and IR spectroscopy. X-ray crystal structure of [ZnLCl]ClO4 showed that the complex contains Zn(II) in a distorted square pyramidal geometry with a N4Cl core. In addition, structural parameters, vibration frequencies, frontier molecular orbitals (FMOs), UV bands and biological activity ranking of mentioned complexes are investigated as theoretically for all complexes. Computational studies of the relevant complexes are performed with the aid of density functional theory (DFT). (C) 2015 Elsevier B.V. All rights reserved., Faculty of Chemistry of Bu-Ali Sina University, Ministry of Science, Research and Technology of Iran; State of Planning Organization [2010K120480]; office of scientific research projects of Cumhuriyet University [F-426], We are grateful to the Faculty of Chemistry of Bu-Ali Sina University, Ministry of Science, Research and Technology of Iran for financial support and the Aksaray University, Science and Technology Application and Research Center, Turkey, for the use of the Bruker Smart Breeze CCD diffractometer (purchased under grant 2010K120480 of the State of Planning Organization). We are also grateful of the office of scientific research projects of Cumhuriyet University (Project No. F-426) for financial supports. This research is made possible by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure).

© 2014 Elsevier Ltd. There is a lack of studies focusing on the chemical compounds involved in quality perception. The present work combines both sensory and chemical approaches with the final goal of evaluating the sensory-active compounds influencing wine experts' and consumers' perception of red wine quality. Perceived quality was categorised by 108 consumers and 119 experts according to four levels going from very low to very high quality. In parallel, samples were described by a descriptive trained panel and volatile and non-volatile chemicals with known sensory activity were quantified. Wines with higher concentrations of eugenol, E- and Z-whiskylactones and 4-ethylphenol (discussed in terms of matrix effect) are perceived higher in quality by consumers, while fusel alcohols and astringent-related compounds such as PAs, cis-aconitic acid, certain flavonols and hydroxycinnamic acid derivatives are linked to lower quality samples. In contrast, experts perceived wines with lower levels of whiskylactones and volatile phenols while higher levels of norisoprenoids to be higher in quality. These results increase the understanding of wine quality perception and can give the wine industry knowledge of the main sensory-active compounds driving quality for different wine consumers., The research reported in this article was financially supported by the Bourgogne council, the Spanish Ministry of Education (AGL2010-22355-CO2-01/02) and Instituto de Estudios Riojanos. M.P.S.N. and J.M.A. acknowledge the Spanish Education Ministry (M.E.C.) for her postdoctoral fellowship and Navarra Government for his predoctoral grant, respectively. Authors also want to thank Marivel Gonzalez-Hernandez and Christelle Pêcher from the Universities of La Rioja and Burgundy, respectively, for their support in the panel training sessions, Patrick Vuchot from Inter-Rhône (Orange and Avignon, France) for his support during the experimentation with consumers and experts, and panellists for their interest and diligence during their participation in the sensory sessions.

WOS: 000340214000011, The natural zeolite (NZ) was obtained from Sivas-Yavu of Turkey and modified by ion-exchange (NH4NO3), alkali treatment (NaOH) and addition of aluminum (Al-2(SO4)(3)). The natural and modified samples were characterized by XRF, XRD, N-2 sorption, FUR, NH3-TPD, particle size distribution, SEM and TGA. Ion-exchange with NH4+ of NZ results in the exchange of the Na+ and Ca2+ cations and the partial exchange of the Fe3+ and Mg2+ cations. While the treatment of the NZ with NaOH leads to insignificant change of almost all cations, it causes significant dealumination and desilication of the NZ. FUR and TGA results showed that decationization, dealumination and desilication give rise to a decrease in hydrophilic nature of NZ. However, manganese adsorption of samples enhances their hydrophilic nature. Ion exchange and aluminum introduction increase surface area and pore volume of samples as well as surface acidity, whereas alkali treatment with NaOH decreases them due to partial collapse of structure with significant desilication and dealumination. All modifications, ion exchange, alkali treatment, and aluminum introduction, increased two times the manganese adsorption capacity of natural zeolites. The Freundlich isotherm model was best fitted to the isotherm data obtained due to a heterogeneous surface existence. (C) 2014 Elsevier B.V. All rights reserved., research fond of Cumhuriyet University [M-492]; Scientific & Technology Research Council of Turkey (TUBITAK) [113 M813], I gratefully acknowledge the financial support given to this work by research fond of Cumhuriyet University (M-492) and The Scientific & Technology Research Council of Turkey (TUBITAK) (113 M813).

WOS: 000349277700020, A novel highly efficient and recyclable catalyst based on Fe@Ag bimetallic nanoParticles involved parninothiophenol (ATP) functionalized calcium alginate (Fe@Ag-ATP-CA) beads was prepared and characterized by transmission electron microscope (TEM), and x-ray photoelectron spectroscopy (XPS). The catalytic properties of 4-nitrophenol (4-NP) and 2-nitrophenol (2-NP) were performed using Fe@Ag-ATP-CA catalyst synthesized in the presence of sodium borohydride (NaBH4). The effects of various variables such as the catalyst dosage, the concentration of sodium borohydride, and temperature were also investigated. The rates of catalytic reduction of 4-NP and 2-NP compounds have been found as the sequence: 4-NP > 2-NP. The kinetic models and the thermodynamic parameters were studied to show the reduction mechanisms. The Fe@Ag-ATP-CA catalyst has highly efficient recyclability and excellent catalytic activity. (C) 2013 Elsevier B.V. All rights reserved.

International audience; Triticale (Triticosecale Wittmack), may be considered as an energy crop because of its fast growth rate, of its potential for human and animal feed but as well, for its lignocellulosic content. Such potential, combined to the fact that it can grow in northern climate has raised significant interest for this plant in Canada. In this work, the non-edible part of the plant (straws) of triticale (Triticosecale Wittmack 'Pronghorn') was fractionated using the Feedstock Impregnation Rapid and Sequential Steam Treatment (FIRSST). Fractionation was performed using both a one and a two-step steam process leading to the isolation of the different macromolecular fractions from lignocellulose. Results showed that in addition to its potential for ethanol production, the two-step FIRSST treatments have shown promising results producing a high quality pulp (selectivity of 94% into alpha-cellulose) whilst allowing direct recovery of solubilized hemicelluloses. After isolation, the C6 carbohydrates from the hemicellulosic fractions were fermented to ethanol after being first hydrolyzed using a non-enzymatic approach. The hydrolyzed hemicellulosic broths were then fermented using Saccharomyces cerevisiae and results showed a high C6 sugar conversion with 96.8 wt% of the glucose converted to ethanol thus producing a mixture of relatively pure xylose

WOS: 000320295300131, Vanadium molybdenum oxide system (VxMo(1-x)Oy for x, Scientific Research Foundation of Yildiz Technical University; HYTEM Laboratory of Mechanical Engineering Department at Nigde University, This work was financially supported by Scientific Research Foundation of Yildiz Technical University and HYTEM Laboratory of Mechanical Engineering Department at Nigde University.

WOS: 000316645100012, PubMed ID: 23298591, The removal of tetracycline (TC) from aqueous environment by new type of sorbents, tannin based cryogels (TAB CRGs) and control cryogels (CRGs) was studied in a batch system. The experimental parameters that affect the sorption of TC were optimized to achieve maximum removal yield. Prepared cryogels were characterized by SEM imaging, IR spectroscopy (ATR). Produced TAB cryogels have thin polymeric walls and interconnected large pores. The TAB cryogels are elastic and sponge like; its water content can easily be removed by only compressed with hand. The TAB cryogels restore their original shape and size within seconds after soaked in water. On the other, elasticity of blank CRG is lower. The Freundlich and Langmuir adsorption isotherms were conducted to deduce the mechanism of the process. The kinetics of TC adsorption was moderately fast and almost reached equilibrium in 150 min and the results followed pseudo-second-order kinetic model. (c) 2012 Elsevier B.V. All rights reserved.

WOS: 000314385100003, Supercritical fluid extraction of pine kernel lipids from Pinus pinea L using green solvents (only CO2 or mixed with ethanol) was performed in a laboratory scale extraction system. For the first time in this study the effect of main operating parameters [i.e. pressure (20-50 MPa), temperature (40-60 degrees C), CO2 flow rate (0.061-0.259 kg h(-1)), entrainer concentration (2.5 and 5 vol.%) and average particle size (362.5 and 725 mu m)] on extraction yield, initial extraction rate and the solved contents of pine kernel lipid in CO2 or its solubility was investigated systematically. Experimental results showed that extraction yields (from 0.477 to 0.488 g PKLg(-1) dry PK) obtained from supercritical CO2 extraction over 30 MPa of operating pressure was better than extraction yield (0.472g PKLg(-1) dry PK) obtained from organic solvent extraction. It should be noted that the extraction yield obtained using 5 vol.% of ethanol reached to 0.487 g PKLg(-1) dry PK in 90 min under a suitable operating condition such as 30 MPa, 40 degrees C and 0.194 kg h(-1) of green solvent flow rate. The crossover effect of pine kernel lipid was determined approximately at 23 MPa of operating pressure. The experimental solubility data, determined by the dynamic method, of pine kernel oil in supercritical CO2 were correlated by some empirical models such as Chrastil, del Valle-Aguilera, Adachi-Lu, and Sparks models. Adachi-Lu and Sparks models made a lower error in the prediction of solubility. Lipids extracted by supercritical green solvents extraction contain more unsaturated fatty acids than those extracted by Soxhlet with in the n-hexane extracts. (C) 2012 Elsevier B.V. All rights reserved., Turkey Republic Ministry of Development [2011K120250]; Cumhuriyet University [CUBAP-REKGUD-III], The research was supported by Turkey Republic Ministry of Development (Project code: 2011K120250) and the Scientific Research Project Fund of Cumhuriyet University (Project code: CUBAP-REKGUD-III).

WOS: 000308733200004, A series of iron containing zeolites with varying Si/Al ratios (11.5-140) and low iron content (similar to 0.9 wt.% Fe) have been synthesised by solid-state ion exchange with commercially available zeolites and tested, for the first time, in the oxidative dehydrogenation of propane (ODHP) with N2O. The samples were characterised by XRD, N-2-Adsorption, NH3-TPD and DR-UV-vis spectroscopy. The acidity of the Fe-ZSM-5 can be controlled by high temperature and steam treatments and Si/Al ratio. The selectivity and yield of propene were found to be the highest over Fe-ZSM-5 with low Al contents and reduced acidity. The initial propene yield over Fe-ZSM-5 was significantly higher than that of Fe-SiO2 since the presence of weak and/or medium acid sites together with oligonuclear iron species and iron oxides on the ZSM-5 are found to enhance the N2O activation. The coking of Fe-ZSM-5 catalysts could also be controlled by reduction of the surface acidity of ZSM-5 and by the use of O-2 in addition to N2O as the oxidant. Fe-ZSM-5 zeolites prepared with solid-state method have been shown to have comparable activity and better stability towards coking compared with Fe-ZSM-5 zeolites prepared by liquid ion exchange and hydrothermal synthesis methods. (C) 2012 Elsevier B.V. All rights reserved., Scientific and Technological Research Council of Turkey [107M236]; EU, Queen's University, Belfast, The authors acknowledge financial support from the Scientific and Technological Research Council of Turkey (107M236) and the EU Transnational Project grant held in CenTACat at Queen's University, Belfast.

A bed containing equal volumes of 1.85 mm glass beads (rho(p)=2500 kg/m(3)) and 0.550 mm ceramic spheres (rho(p)=3800 kg/m(3)), was fluidized by water in a 191 mm i.d. cylindrical column. The water velocity was varied from 16.5 to 52.5 mm/s to investigate the phenomenon of layer inversion at three temperatures (5, 10 and 20 degrees C). The inversion velocity was found to decrease by 7% on reducing the temperature from 20 to 10 degrees C, with no further decrease at 5 degrees C. The operating temperature had an important effect on the degree of separation between the two solids. In contrast to what has been reported for columns of smaller diameter, gross circulation was found to play an important role in enhancing particle mixing. Quantitative and qualitative predictions of layer inversion and binary component segregation at different liquid velocities and of chaotic circulation patterns were carried out by Eulerian-Lagrangian Computational Particle-Fluid Dynamics (CPFD) modelling, using Barracuda software. The predictions are in reasonable agreement with the experimental observations. (C) 2012 Elsevier Ltd. All rights reserved.

WOS: 000301320300018, PubMed ID: 22331036, Two different natural zeolites having different phase compositions were obtained from different regions of Turkey and modified by ion-exchange (0.5 M NH4NO3) and acid leaching using 1 M HCl. The natural and modified samples were treated at low temperature (LT), high temperature (HT) and steam (ST) conditions and characterised by XRF, XRD, BET, FTIR, DR-UV-Vis, NH3-TPD and TGA. Ion-exchange with NH4+ of natural zeolites results in the exchange of the Na+ and Ca2+ cations and the partial exchange of the Fe3+ and Mg2+ cations. However, steam and acidic treatments cause significant dealumination and decationisation, as well as loss of crystalline, sintering of phases and the formation of amorphous material. The presence of mordenite and quartz phases in the natural zeolites increases the stability towards acid treatment, whereas the structure of clinoptilolite-rich zeolites is mostly maintained after high temperature and steam treatments. The natural and modified zeolites treated at high temperature and in steam were found to be less stable compared with synthetic zeolites, resulting in a loss of crystallinity, a decrease in the surface area and pore volume, a decrease in the surface acidity as well as dealumination, and decationisation. (C) 2012 Elsevier Inc. All rights reserved., Scientific and Technological Research Council of Turkey (TUBITAK) [107M435], This work was supported by The Scientific and Technological Research Council of Turkey (TUBITAK) under the Project Number of 107M435 as well as some experiments carried out in CenTACat School of Chemistry and Chemical Engineering at Queen's University Belfast with EU transnational programme.

WOS: 000303958300020, This paper presents a novel effective method for the optimization of some operating parameters of a laboratory scale thickener on the dewatering performance with multiple performance characteristics based on the grey relational analysis (GRA). Lab-scale thickener operation parameters including feed flowrate, solid percent, flocculant dosage and feedwell height were optimized based on multiple performance characteristics. Sixteen experiments were conducted using GRA to optimize the parameters for lab-scale thickener parameters to generate two quality characteristics (the underflow solid percent and bed height of thickener). Analysis of the grey relational grade indicates that parameter significance and the optimal parameter combination for the lab-scale thickener are identified. The analytical results from two confirmation experiments using the optimal process parameters confirm that the above performance characteristics in dewatering of tailing can be improved effectively through this approach. (C) 2012 Elsevier B.V. All rights reserved.

WOS: 000297234400007, The natural zeolite obtained from the Sivas-Yavu region in Turkey and iron modified forms were studied for the decomposition of N(2)O and selective catalytic reduction of N(2)O with NH(3). The natural and iron modified zeolites were characterised by XRD, SEM, H(2)-TPR, NH(3)-TPD and low temperature nitrogen sorption. The effect iron loading, precursor and valency on the catalytic performance of catalysts were studied. The catalytic activity of the zeolites increased up to about 7.0 wt.% Fe. Above this value, the activity decreased as a result of a reduction in the surface area and pore volume of the zeolite. The highest catalytic activity was observed using catalysts prepared with FeCl(2) due to the formation of more reducible iron species in the zeolites. When FeSO(4) was used as the iron precursor, sulphate remained on the surface even after extensive washing resulting in a decrease in the N(2)O decomposition activity and a shift the N(2)O reduction temperature to higher values. Since the natural and iron exchanged natural zeolites prepared using FeCl(2) have comparable activity with synthetic zeolites, the offer a promising alternative catalyst for the abatement of N(2)O, particularly for the selective reduction of N(2)O with NH(3). (C) 2011 Elsevier B.V. All rights reserved., German Academic Exchange Program (DAAD); Cumhuriyet University [M280]; The Scientific & Technology Research Council of Turkey [104M433], We gratefully acknowledge German Academic Exchange Program (DAAD) for Equipment grant and the financial support of this work by Research fund of Cumhuriyet University (M280) and The Scientific & Technology Research Council of Turkey (104M433).

WOS: 000294512100007, In this study, pumpkin seeds, called as "Urgup Sivrisi" and grown in Cappadocia region, were used as plant materials because of high aroma contents. In the supercritical fluid extraction of pumpkin seed oil, the effect of main process parameters as the particle size (250-2360 mu m), the volumetric flow rate of supercritical solvent (0.06-0.30 L/h), the operating pressure (20-50 MPa), the operating temperature (40-70 degrees C), the type of entrainer (ethanol and n-hexane) and those concentrations (0-10 vol.%) on the extraction yield, the oil solubility and the initial extraction rate were investigated. A cross-over effect for the extraction of pumpkin seed oil using supercritical CO(2) was determined at the operating pressure of 20-30 MPa. The maximum extraction yield obtained with entrainer free was reached 0.50 g oil/g dry seed at 600-1180 mu m. 0.12 L/h, 50 MPa and 70 degrees C for the operation time of 5 h. The maximum extraction yield obtained with ethanol as an entrainer in the experiments was reached 0.54 g oil/g dry seed at the conditions of 600-1180 mu m. 0.12 L/h, 30 MPa, 40 degrees C and 8 vol.% for the operating time of 2 h. The oil compositions were determined by gas chromatography analysis and the results showed that the compositions of pumpkin seed oil which were obtained by means of organic solvent extraction and supercritical fluid extraction were similar. The average oil compositions determined as 9.3 (+/- 0.43)% palmitic acid, 7.5 (+/- 0.6)% stearic acid, 32.3 (+/- 0.6)% oleic acid, 48.1 (+/- 0.6)% linoleic acid and 0.7 (+/- 0.3)% linolenic acid. The morphological changes in the seeds were determined by the scanning electron microscopy analysis. (C) 2011 Elsevier B.V. All rights reserved., Cumhuriyet University [CUBAP-M404]; State Planning Organization (SPO) [2011K120250], The present work is part of the master thesis of Mr. Hasan Korkmaz. The authors acknowledge the financial supports provided by Cumhuriyet University Scientific Research Projects (Project code: CUBAP-M404) and by State Planning Organization (SPO Project code: 2011K120250). We would like to thank Mr. Hursit Simsek (Simaksan Company, Nevsehir, Turkey) for providing the pumpkin seed material.

WOS: 000272279000008, Conductive poly(2-ethyl aniline) (PEAn)/kaolinite composite was prepared by chemical polymerization in aqueous HCl medium in the presence of kaolinite particles by using potassium chromate (K2CrO4) as oxidant. Effects of polymerization conditions, such as concentrations of oxidant and 2-ethyl aniline, polymerization time and temperature on PEAn content and conductivity of composite, were investigated. The prepared composite material, having the highest PEAn content and conductivity, was obtained in the polymerization carried out at 20 degrees C for 2 h with 0.2 M K2CrO4 and 0.2 M EAn. It was observed that the micro-hardness of prepared composites increased with the increase in the PEAn contents of composites. The highest micro-hardness value of 7.92 kg mm(-2) was reached at 24.6% PEAn content. Characterization of composites was carried out by FTIR spectroscopy, XRD, TGA and SEM techniques. (C) 2009 Elsevier B.V. All rights reserved.

WOS: 000262877300012, In this study, the optimization of some parameters on agglomeration performance of Zonguldak bituminous coal by oil agglomeration was discussed. A three-level Box-Behnken design combining with a response surface methodology (RSM) and quadratic programming (QP) were employed for modeling and optimization some operations parameters on oil agglomeration performance. The relationship between the responses, Le., grade and recovery, and four process parameters, i.e., amount of oil, agitation time, agitation rate and solid content were presented as empirical model equations for both grade and recovery on oil agglomeration. The model equations were then optimized individually using the quadratic programming method to maximize both for grade and recovery within the experimental range studied. The optimum conditions were found to be 14.61% for amount of oil, 8.94 min for agitation time, 1554 rpm for agitation rate and 5% for solid content to achieve the maximum grade. The maximum model prediction of 0.650 grade at these optimum conditions is higher than any value obtained in the initial tests conducted. Similarly, the conditions for maximum recovery were found to be 20.60% for amount of oil, 5 min for agitation time, 1800 rpm for agitation rate and 19.48% for solid content with a prediction of 96.90% recovery, which is also higher than any other recovery obtained in the initial tests conducted. (C) 2008 Elsevier Ltd. All rights reserved.

WOS: 000261537800050, In this study, a blend of poly(vinyl chloride) (PVC)/ethylene-co-vinyl acetate (EVA) was compatibilized by terpolymer of maleic anhydride-styrene-vinyl acetate (MAStVA) used as a compatibilizer. It was prepared the blends of 50/50 PVC/EVA containing 2-10% of the terpolymer. The compatibility experiences of these blends were investigated by using viscometric method in the range of concentrations (0.5-2.0 g dL(-1)) where tetrahydrofuran (THF) is the solvent. The interaction parameter (Delta b) was used to Study the miscibility and compatibility of polymer blend in solution, obtained from the modified Krigbaum and Wall theory. Turbidity and FTIR measurements were also used to investigate the miscibility of this pair of polymers. The values of the relative viscosities of the each polymer solution and their blends were measured by a Cannon-Fenske type viscometer. In consequence of the study, it was observed that a considerable improvement was achieved in the miscibility of PVC/EVA blends by adding among 5 and 10 wt% of compatibilizer. (C) 2008 Elsevier B.V. All rights reserved.

WOS: 000251576100010, Natural zeolites obtained from various regions of Turkey and their iron-exchanged forms were characterised by XRD, BET, H-2-TPR and NH3-TPD methods. Transient experiments with N2O showed that the iron introduced into natural zeolites have appreciable oxygen deposition capacity due to isolated iron species involved. Atomic surface oxygen species in these zeolites are formed at 250 degrees C, which is released through increasing the temperature until 900 degrees C, similar to Fe-containing ZSM-5 zeolite. The steady-state experiments indicate that the iron-containing zeolite of the Yavu-Sivas region, in particular, has high activity in selective catalytic reduction of N2O With NH3 as a consequence of isolated cationic and/or dimeric iron content. (C) 2007 Elsevier B.V. All rights reserved.

WOS: 000242642500006, In this study, the extraction of jojoba seed oil obtained from jojoba seed using both supercritical CO2 and supercritical CO2+ethanol mixtures was investigated. The recovery of jojoba seed oil was performed in a green and high-tech separation process. The extraction operating was carried out at operating pressures of 25, 35 and 45 MPa, operating temperatures of 343 and 363 K, supercritical fluid flow rates of 3.33 x 10(-8), 6.67 x 10(-8) and 13.33 x 10(-8) m(3) s(-1), entrainer concentrations of 2, 4 and 8 vol.%, and average particle diameters of 4,1 X 10(-4) 6.1 X 10(-4), 8.6 x 10(-4) and 1.2 x 10(-3) M. It was found that a green chemical modifier such as ethanol could enhance the solubilities, initial extraction rate and extraction yield of jojoba seed oil from the seed matrix as compared to supercritical CO2. In addition, it was found that the solubility, the initial extraction rate and the extraction yield depended on operating pressure and operating temperature, entrainer concentration, average particle size and supercritical solvent flow rate. The solubility of jojoba seed oil and initial extraction rate increased with temperature at the operating pressures of 35 and 45 MPa and decreased with increasing temperature at the operating pressure of 25 MPa. Furthermore, supercritical fluid extraction involved short extraction time and minimal usage of small amounts entrainer to the CO2. About 80% of the total jojoba seed oil was extracted during the constant rate period at the pressure of 35 and 45 MPa. (C) 2006 Elsevier B.V. All rights reserved.

WOS: 000238409300029, A systematic study on the effects of ionic environments on the adsorption and diffusion characteristics of bovine serum albumin (BSA) inside/on 100 kDa polyether sulfone (PES) membranes was carried out. Static adsorption of BSA was investigated at the solution pH values of 3.78, 4.78, and 6.80; for the ionic-strengths of 0.01 and 0.1 M. Isotherms for BSA adsorption on PES membranes were correlated by the Freundlich equation. The maximum adsorption occurred at the pH value below the isoelectric point of the protein. With increasing ionic strength, the adsorbed protein on the membrane decreased. van der Waals and electrostatic interactions energies between the membrane and the protein were calculated by using the DVLO theory. Diffusion coefficients of BSA inside PES membranes were calculated by employing experimental data evaluated in a diffusion cell along with the data of adsorption isotherms into a developed model based on mass-balance. To detect the structural changes occurred, membrane surfaces were analysed by FT-IR-ATR measurements and SEM images. The results of the adsorption and diffusion experiments showed that adsorption and diffusive characteristics of BSA in 100 kDa PES membranes are agreed well with the theoretical calculations. (c) 2005 Elsevier B.V. All rights reserved.

International audience; The photocatalytic degradation of the fungicide fenamidone is studied in a TiO2-coated optical fiber photoreactor. Fenamidone is slowly transformed with a kinetic order of 1 and a degradation rate of 0.02 h(-1). Intermediate products were isolated and identified by means of solid phase extraction (SPE) coupled to liquid chromatography-mass spectrometry techniques (LC-MS). A proposed degradation pathway of fenamidone is presented, involving mainly hydroxylation and oxidation reactions. Carboxylic acids and sulfate ions resulting from the same reaction in a powder reactor were also identified.

WOS: 000229812200010, PubMed ID: 18970026, The fly ash samples obtained from Kangal Power Plant were prepared for FAAS analysis by a new approach. The trace elements of the fly ash samples were leached with appropriate solvents under suitable conditions. The leaching method is known as an effective technique for substances dissolving very hard and refractory materials. The leaching effects of solvents and their mixtures were investigated on fly ash samples that are used largely in analysis of soil and sediment samples. The fly ashes mainly consist of glassy aluminosilicates. The major components of the samples are SiO2, Al2O3, CaO and Fe2O3. Therefore, decomposition of the silicate lattice of the fly ash is required for liberation of trace elements. The dissolution process can be completed by using a mineral acid such as concentrated HCl. This technique has an advantage that the fly ash can be dissolved without any oxidation at room temperature. Maximum element recoveries were obtained by the procedure of 37% HCl leaching after the samples were treated with 2.0 ml of concentrated HE It was also observed that maximum mass loss occurred in this procedure. The effect of the four leaching reagents, which are HCl, HNO3, HClO4 and HNO3 + HClO4. were investigated on fly ash samples that were treated with concentrated HF. An optimum leaching method was determined based on the confidence of analytical results and element recovery rates. (c) 2004 Elsevier B.V. All rights reserved.

WOS: 000083546800003, The biosorption of copper(II), nickel(II) and chromium(VI) from aqueous solutions on dried (Chlorella vulgaris, Scenedesmus obliquus and Synechocystis sp.) algae were tested under laboratory conditions as a function of pH, initial metal ion and biomass concentrations. Optimum adsorption pH values of copper(II), nickel(II) and chromium(VI) were determined as 5.0, 4.5 and 2.0. respectively, for all three algae. At the optimal conditions, metal ion uptake increased with initial metal ion concentration up to 250 mg l(-1). Experimental results also showed the influence of the alga concentration on the metal uptake for all the species. Both the Freundlich and Langmuir adsorption models were suitable for describing the short-term biosorption of copper(IT), nickel(II) and chromium(VI) by all the algal species. (C) 1999 Elsevier Science Ltd. All rights reserved.

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