Ahmet Şahan - Academia.edu (original) (raw)

Papers by Ahmet Şahan

Research paper thumbnail of Morphological Studies of 2+ 0 Anatolian Black Pine Stocks Grown in Eskişehir, Eğirdir and Seydişehir Forest Nurseries

Turk. J. Agric. For, 1999

Abstract: Two year-old nursery stocks of Anatolian black pine (Pinus nigra Arnold subsp. pallasia... more Abstract: Two year-old nursery stocks of Anatolian black pine (Pinus nigra Arnold subsp. pallasiana (Lamb.) Holmboe) from nine provenances were examined for morphological properties such as height, root collar diameter, sturdiness and shoot: root ratio. The stocks were grown in ...

Research paper thumbnail of The types of urodynamic detrusor overactivity and its relationship with neurological diseases. 10-years follow-up of 1000 invasive urodynamic studies

Eastern Journal Of Medicine, 2021

The aim of this study is to compare detrusor overactivity (DO) subtypes namely terminal (TDO) and... more The aim of this study is to compare detrusor overactivity (DO) subtypes namely terminal (TDO) and phasic (PDO) in terms of frequency, etiologic reasons, urodynamic findings and relationships with neurological diseases. Patients' characteristics including age, gender, neurological diseases, were noted. Bladder volume on the first desire to voiding (FSD), the strong desire to voiding (SDV), maximum bladder capacity (MBC), bladder compliance (BC), presence and type of DO, and amplitude of DO (Ad) were also noted during the IUDS. Patients with TDO and PDO were compared in terms of patient characteristics, urodynamic parameters, and neurological diseases. 1018 patients were enrolled in the study. Neurological disease was noted in 180 patients; spinal cord trauma (

Research paper thumbnail of On-line preconcentration/determination of zinc from water, biological and food samples using synthesized chelating resin and flame atomic absorption spectrometry

Journal of Trace Elements in Medicine and Biology, 2013

An on-line flow injection pre-concentration-flame atomic absorption spectrometry method was devel... more An on-line flow injection pre-concentration-flame atomic absorption spectrometry method was developed to determine trace zinc in water (tap, dam, and well water), biological (hair and nail), and liver samples. As a solid phase extractant, a synthesized new chelating resin, poly(2-thiozylmethacrylamide-co-divinylbenzene-co-2-acrylamido-2-methyl-1-propane sulfonic acid) was used. The resin was characterized by Fourier transform infrared spectroscopy, elemental analysis, and surface area by nitrogen sorption. A pre-concentration factor of 40-fold for a sample volume of 12.6 mL was obtained by using the time-based technique. The detection limit for the pre-concentration method was found to be 2.2 μg L(-1). The precision (as RSD,%) for 10 replicate determinations at the 0.04 μg mL(-1) Zn concentration was 1.2%. The calibration graph using the pre-concentration system for zinc was linear with a correlation coefficient of 0.998 in the concentration range from 0.005 to 0.05 μg mL(-1). The applicability and accuracy of the developed method were estimated by the analysis spiked water, biological, liver samples (83-105%), and also certified reference material TMDA-70 (fortified lake water) and SPS-WW1 Batch 111-Wastewater. The results were in agreement with the certified values.

Research paper thumbnail of Synthesis and Semi-conducting Properties of Novel 2-(4-Chloro-1-naphtyloxy)-2-oxoethyl Methacrylate with 2-(Dimethylamino)Ethyl Methacrylate Copolymers, Quaternized Amino Groups

Journal of Macromolecular Science, Part A, 2010

Methacrylate based monomer, 2-(4-chloro-1-naphtyloxy)-2-oxoethyl methacrylate (ClNOEMA) was synth... more Methacrylate based monomer, 2-(4-chloro-1-naphtyloxy)-2-oxoethyl methacrylate (ClNOEMA) was synthesized by reacting 4-chloro-1-naphthyloxychloromethylketone with sodiummethacrylate in acetonitrile solvent at 70°C in the presence of triethylbenzylammonium chloraid as phase transfer matter. The free-radical initiated copolymerization of (ClNOEMA), with 2-(dimethylamino)ethyl methacrylate (DMAEMA) was carried out in 1,4-dioxane solution at 70 ± 1°C using 2,2′-azobisisobutyronitrile (AIBN) as an initiator with 50%–50% monomer-to-monomer ratio in the feed. This copolymer has been converted into a novel salts by reaction with the iodemethane (CH3I). The copolymers and the corresponding salts have been characterized fully by a range of spectroscopic and thermal analysis techniques. The electrical conductivity dependence of temperature of the polymers were measured and the polymers exhibit the semiconducting behavior, confirming that the electrical conductivity increases with increasing temperature. The poly(CINOEMA-co-DMAEMA) polymer doped by CH3I for 5 min shows the highest conductivity. The optical band gap, activation energy and room temperature conductivity values of this polymer were obtained to be 2.16 eV, 0.141 eV and 3.9×10 S/cm, respectively. These electronic parameters suggest that the poly(CINOEMA-co-DMAEMA) [0.23:0.77] polymer doped by CH3I for 5 min is an organic semiconductor with the thermally activated conduction mechanism.

Research paper thumbnail of Morphological Studies of 2+ 0 Anatolian Black Pine Stocks Grown in Eskişehir, Eğirdir and Seydişehir Forest Nurseries

Turk. J. Agric. For, 1999

Abstract: Two year-old nursery stocks of Anatolian black pine (Pinus nigra Arnold subsp. pallasia... more Abstract: Two year-old nursery stocks of Anatolian black pine (Pinus nigra Arnold subsp. pallasiana (Lamb.) Holmboe) from nine provenances were examined for morphological properties such as height, root collar diameter, sturdiness and shoot: root ratio. The stocks were grown in ...

Research paper thumbnail of The types of urodynamic detrusor overactivity and its relationship with neurological diseases. 10-years follow-up of 1000 invasive urodynamic studies

Eastern Journal Of Medicine, 2021

The aim of this study is to compare detrusor overactivity (DO) subtypes namely terminal (TDO) and... more The aim of this study is to compare detrusor overactivity (DO) subtypes namely terminal (TDO) and phasic (PDO) in terms of frequency, etiologic reasons, urodynamic findings and relationships with neurological diseases. Patients' characteristics including age, gender, neurological diseases, were noted. Bladder volume on the first desire to voiding (FSD), the strong desire to voiding (SDV), maximum bladder capacity (MBC), bladder compliance (BC), presence and type of DO, and amplitude of DO (Ad) were also noted during the IUDS. Patients with TDO and PDO were compared in terms of patient characteristics, urodynamic parameters, and neurological diseases. 1018 patients were enrolled in the study. Neurological disease was noted in 180 patients; spinal cord trauma (

Research paper thumbnail of On-line preconcentration/determination of zinc from water, biological and food samples using synthesized chelating resin and flame atomic absorption spectrometry

Journal of Trace Elements in Medicine and Biology, 2013

An on-line flow injection pre-concentration-flame atomic absorption spectrometry method was devel... more An on-line flow injection pre-concentration-flame atomic absorption spectrometry method was developed to determine trace zinc in water (tap, dam, and well water), biological (hair and nail), and liver samples. As a solid phase extractant, a synthesized new chelating resin, poly(2-thiozylmethacrylamide-co-divinylbenzene-co-2-acrylamido-2-methyl-1-propane sulfonic acid) was used. The resin was characterized by Fourier transform infrared spectroscopy, elemental analysis, and surface area by nitrogen sorption. A pre-concentration factor of 40-fold for a sample volume of 12.6 mL was obtained by using the time-based technique. The detection limit for the pre-concentration method was found to be 2.2 μg L(-1). The precision (as RSD,%) for 10 replicate determinations at the 0.04 μg mL(-1) Zn concentration was 1.2%. The calibration graph using the pre-concentration system for zinc was linear with a correlation coefficient of 0.998 in the concentration range from 0.005 to 0.05 μg mL(-1). The applicability and accuracy of the developed method were estimated by the analysis spiked water, biological, liver samples (83-105%), and also certified reference material TMDA-70 (fortified lake water) and SPS-WW1 Batch 111-Wastewater. The results were in agreement with the certified values.

Research paper thumbnail of Synthesis and Semi-conducting Properties of Novel 2-(4-Chloro-1-naphtyloxy)-2-oxoethyl Methacrylate with 2-(Dimethylamino)Ethyl Methacrylate Copolymers, Quaternized Amino Groups

Journal of Macromolecular Science, Part A, 2010

Methacrylate based monomer, 2-(4-chloro-1-naphtyloxy)-2-oxoethyl methacrylate (ClNOEMA) was synth... more Methacrylate based monomer, 2-(4-chloro-1-naphtyloxy)-2-oxoethyl methacrylate (ClNOEMA) was synthesized by reacting 4-chloro-1-naphthyloxychloromethylketone with sodiummethacrylate in acetonitrile solvent at 70°C in the presence of triethylbenzylammonium chloraid as phase transfer matter. The free-radical initiated copolymerization of (ClNOEMA), with 2-(dimethylamino)ethyl methacrylate (DMAEMA) was carried out in 1,4-dioxane solution at 70 ± 1°C using 2,2′-azobisisobutyronitrile (AIBN) as an initiator with 50%–50% monomer-to-monomer ratio in the feed. This copolymer has been converted into a novel salts by reaction with the iodemethane (CH3I). The copolymers and the corresponding salts have been characterized fully by a range of spectroscopic and thermal analysis techniques. The electrical conductivity dependence of temperature of the polymers were measured and the polymers exhibit the semiconducting behavior, confirming that the electrical conductivity increases with increasing temperature. The poly(CINOEMA-co-DMAEMA) polymer doped by CH3I for 5 min shows the highest conductivity. The optical band gap, activation energy and room temperature conductivity values of this polymer were obtained to be 2.16 eV, 0.141 eV and 3.9×10 S/cm, respectively. These electronic parameters suggest that the poly(CINOEMA-co-DMAEMA) [0.23:0.77] polymer doped by CH3I for 5 min is an organic semiconductor with the thermally activated conduction mechanism.