ABSTRACT In order to have a good interpretation of the illumination effect on the capacitance-vol... more ABSTRACT In order to have a good interpretation of the illumination effect on the capacitance-voltage (C-V) and conductance-voltage (G/ω-V) profiles, C-V and G/ω-V characteristics of the polyvinyl alcohol (Co, Zn-Doped)/n-Si Schottky barrier diodes (SBDs) were investigated in the wide frequency and applied bias voltage ranges at room temperature. Experimental results show that the values of both C and G/ω are strong functions of frequency and applied bias voltage in dark and under illumination (200 W) conditions. It is clear that the dispersion in C and G/ω is considerably high in the depletion and accumulation regions due to illumination induced electron-hole pairs and series resistance (Rs) effect, respectively. The values of C and G/ω exponentially decrease with the increasing frequency and at high frequencies (f>100 kHz) the values of C and G/ω become almost independent of frequency both in dark under illumination.
Recently, sensing, recognition and detection of analytes with chemosensors have become a hot topi... more Recently, sensing, recognition and detection of analytes with chemosensors have become a hot topic of interest in host/guest and supramolecular chemistry. Anion sensing has specially grown to be a major field in the last decades. Therefore, the development of new chromogenic dye sensors or receptors for selective determination of anions has become attractive because of the importance of anions in environmental, biological, and chemical processes. It is widely known that anions like fluoride, acetate, cyanide, chloride, iodide, and phosphate anions are significant in human health. The fluoride, especially, is a biologically important ion because of its role in the treament of dental cavities and osteoporosis. However, excess fluoride can cause serious damage to the thyroid, bones, and the kidneys. The acetate anion also plays a critical role in many metabolic processes, and exhibits specific biochemical behavior on antibodies and enzymes.
Toplumlarin kalkinmasinda vazgecilmez bir oneme sahip olan ilkokul egitimi ve niteligi sorunu Tur... more Toplumlarin kalkinmasinda vazgecilmez bir oneme sahip olan ilkokul egitimi ve niteligi sorunu Turkiye’de II. Mesrutiyetten itibaren tartisilmaya baslanmistir. Toplumsal gelismenin saglanabilmesi icin ilk egitimde okutulan derslerin muhtevasi degistirilmis ve derslere farkli misyonlar yuklenmistir. Cumhuriyetin ilaninin ardindan bu konuda yeni duzenlenmeler yapilmis ve hazirlanan yeni mufredat programlari ile cumhuriyetin kazanimlarina sahip cikacak vatandaslar yetistirilmek istenmistir. Bu amacla hazirlanan 1926 Ilk Mektepler Mufredat Programina eklenen ve icerigi degistirilen Hayat Bilgisi ve Tabiat Dersleri ile ilkokul ogrencilerinin gelecekte saglikli, memleket gerceklerinden haberdar, iktisatli ve modern bir vatandas olarak yetismeleri istenmistir.
Ketorolac (KC) suffers from the general side effects of NSAIDs, owing to presence of free carboxy... more Ketorolac (KC) suffers from the general side effects of NSAIDs, owing to presence of free carboxylic acid group. The study aimed to retard the adverse effects of gastrointestinal origin. Ten prodrugs of KC were synthesized by amidation with ethyl esters of amino acids, namely, glycine, L-phenylalanine, L-tryptophan, L-valine, L-isoleucine, L-alanine, L-leucine, L-glutamic acid, L-aspartic acid and b-alanine. Purified synthesized prodrugs were characterized by m.p., TLC, solubility, partition coefficients, elemental analyses, UV, FTIR, NMR and MS. Synthesized prodrugs were subjected for biopharmaceutical studies, analgesic, anti-inflammatory activities and ulcerogenic index. Marked reduction of ulcerogenic index and comparable analgesic, anti-inflammatory activities were obtained in all cases as compared to KC. Among synthesized prodrugs, viz. AR-11, AR-19 and AR-20 showed excellent pharmacological response and encouraging hydrolysis rate both in SIF and in 80% human plasma. Prodrugs with increased aliphatic side chain length or introduction of aromatic substituent showed enhanced partition coefficient but diminished dissolution and hydrolysis rates. Such prodrugs can be considered for sustained release purpose.
Molecular Crystals and Liquid Crystals, Dec 27, 2011
A new Schiff base complex N-(4-bromobenzylidene)-N′-(2-pyridyl) hydrazine, C12H10N3Br, has been s... more A new Schiff base complex N-(4-bromobenzylidene)-N′-(2-pyridyl) hydrazine, C12H10N3Br, has been synthesized and characterized by elemental analyses, mass, H NMR, ultraviolet–visible (UV–VIS), and IR spectroscopy and single-crystal X-ray determination. The p-Br-benzene and pyridine rings are almost planar and the dihedral angle between the planes is 11.1(3)°. The crystal structure is stabilized by intermolecular N‒H…N‒Py hydrogen bonding interaction. X-ray diffraction analyses show that N-(4-bromobenzylidene)-N′-(2-pyridyl) hydrazine Schiff base molecule crystallizes in the monoclinic system, P21/c space group, a = 5.611(5) Å, b = 19.566(5) Å, c = 10.715(5) Å, β = 98.766(5)°, and V = 1162.60(12) Å.
Dielectric properties and ac electrical conductivity (σ ac ) of Au/PVA(Co, Zn acetate)/n-Si and A... more Dielectric properties and ac electrical conductivity (σ ac ) of Au/PVA(Co, Zn acetate)/n-Si and Au/PVA(Ni, Zn acetate)/n-Si Schottky diodes (SDs) have been investigated in dark and under illumination by using experimental capacitance-voltage (C-V) and conductance-voltage (G/ω-V) measurements at 1 MHz and room temperature. Experimental results indicate that the change in dielectric constant (ε'), dielectric loss (ε''), loss tangent (tanδ), the real (M') and imaginary (M'') parts of electric modulus and ac electrical conductivity (σ ac ) with illumination were found to change linearly with illumination level (P). On the other hand, the ε', ε'', tanδ and σ ac vs P have positive slope while the M' and M'' vs P have negative slope. Such behavior of dielectric properties and σ ac can be attributed to illumination induced electron-hole pairs under illumination effect in the depletion region of SDs. The obtained results under illumination suggest that these devices can be used as a sensor in optical applications.
Amino acid Schiff bases, [NaL]·nH2O (L = N-(2-hydroxy-5-nitrobenzylidene)alaninate, N-(2-hydroxy-... more Amino acid Schiff bases, [NaL]·nH2O (L = N-(2-hydroxy-5-nitrobenzylidene)alaninate, N-(2-hydroxy-5-nitrobenzylidene)valinate, and N-(2-hydroxy-5-nitrobenzylidene)phenylalaninate), were synthesized as monosodium salts (L1Na–L3Na). The structures of the monosodium salts were confirmed on the basis of elemental analysis, conductivity measurements, UV–vis, FT-IR, and 2D NMR (HMQC) spectroscopies. L1Na was also structurally determined by single-crystal X-ray diffraction. Hydrogen bond between the amino N(2)–H and phenolate O(1) of the salicylidene part of the molecule played important roles in stabilizing the zwitterion crystal structure. The ranges of the D–H…A angles and those of the H…A and D…A distances indicated the presence of short hydrogen bonds in the structure. In addition, the monosodium salts have been evaluated for in vitro antioxidant activity. Iron(III) complexes (L1Fe–L3Fe) have been obtained by reaction of the appropriate ligand with iron(III) chloride in a 2 : 1 M ratio. Fe(III) complexes were characterized by elemental and thermal analysis, conductivity and magnetic susceptibility measurements, UV–vis, FT-IR, and X-ray photoelectron spectroscopy methods. Graphical abstract
A new Schiff-base complex 2-{(E)-[2hydroxyphenyl)imino]methyl}phenol has been synthesized and cha... more A new Schiff-base complex 2-{(E)-[2hydroxyphenyl)imino]methyl}phenol has been synthesized and characterized by elemental analyses, UV-VIS and IR spectroscopy and single crystal X-ray determination. The structure comprises two independent and similar molecules. The two independent molecules in the asymmetric unit are hydrogen bonded and have different conformations. In each molecule, C 13 H 11 NO 2 , adopt an E configuration about the azomethine C-N double bond. The complex crystallized in the triclinic space group P-1. Two benzene rings and azomethine group are practically coplanar, as a result of intramolecular hydrogen bonds involving the hydroxy O atom and azomethine N atom. Also hydroxy group of the molecule is the presence intermolecular O-HÁÁÁO hydrogen bonds with the hydroxy group of the other molecule.
Notwithstanding the different names given to science courses, they existed in all primary and mid... more Notwithstanding the different names given to science courses, they existed in all primary and middle school curricula beginning with the first curriculum of the Republic of Turkey released in 1924. In this study, the physics topics included in the middle school science curricula released in
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Jun 1, 2014
ABSTRACT In this work, N-(4-Methylbenzylidene)-N'-(2-carboxyphenyl) hydrazine, C15H14N2O2... more ABSTRACT In this work, N-(4-Methylbenzylidene)-N'-(2-carboxyphenyl) hydrazine, C15H14N2O2, Schiff base molecule has been synthesized and characterized by elemental analyses, UV-Vis and IR spectroscopy and single crystal X-ray determination. The molecule of the title compound adopt an E configuration about the azomethine CN double bond. The benzene and phenyl rings are planar and the dihedral angle between the planes is 7.2(2)°. The crystal structure is stabilized by intermolecular OH⋯O and intramoleculer NH⋯O hydrogen bonding interactions. X-ray diffraction analyses show that, N-(4-Methylbenzylidene)-N'-(2-carboxyphenyl) hydrazine Schiff base molecule crystallizes in the monoclinic system, P21/c space group, a=4.392(5)Å, b=22.340(5)Å, c=13.528(5)Å, β=92.882(5)°, V=1325.7(16)Å(3), Z=4. The conformational analysis of N-(4-Methylbenzylidene)-N'-(2-carboxyphenyl) hydrazine was performed by the density functional theory (DFT) B3LYP method using the 6-311++G(d,p) basis set. Also, theoretical values of FTIR and UV-Vis were performed by the same method. The calculated geometry parameters, IR and UV-Vis results were compared with experimental results.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Erzincan Üniversitesi Eğitim Fakültesi Dergisi, Dec 1, 2009
Öğrencilerde çevreye duyarlı davranışların oluşturulmasında formal eğitimin en önemli öğeleri ola... more Öğrencilerde çevreye duyarlı davranışların oluşturulmasında formal eğitimin en önemli öğeleri olan öğretmenlerin rolü oldukça fazladır. Bu noktada öğrencilerin model olarak aldıkları öğretmenlerin su tüketimi davranışları oldukça önemlidir. Bu nedenle öğretmen yetiştiren kurumlarda, öğretmen adaylarına bilinçli su tüketimi davranışlarının kazandırılması gerekmektedir. Yapılan bu çalışma ile öğretmen adaylarının su tüketimi davranışlarının belirlenmesi ve hatalı olanların düzeltilmesi noktasında bazı öneriler getirilmesi amaçlanmıştır. 2007-2008 öğretim yılı bahar döneminde yapılan araştırmanın örneklemini Atatürk Üniversitesi Kazım Karabekir Eğitim Fakültesi Ortaöğretim Bölümü biyoloji, fizik ve kimya öğretmenliği son sınıfında okuyan 139 öğretmen adayı oluşturmaktadır. Öğretmen adaylarının su tüketimi davranışlarının belirlenmesinde araştırmacılar tarafından geliştirilen ve üçlü likert tipte hazırlanan 13 maddelik "Bilinçli Su Tüketimi Anketi" kullanılmıştır. Çalışma sonucunda öğretmen adaylarının su tasarrufuna fazla dikkat etmedikleri sonucuna varılmıştır. Bununla birlikte adayların su tüketimi davranışlarının cinsiyetlerine, yaşlarına, öğrenim gördükleri bölümlere ve yaşadıkları yerleşim birimlerine göre farklılaşmadığı belirlenmiştir.
ABSTRACT In order to have a good interpretation of the illumination effect on the capacitance-vol... more ABSTRACT In order to have a good interpretation of the illumination effect on the capacitance-voltage (C-V) and conductance-voltage (G/ω-V) profiles, C-V and G/ω-V characteristics of the polyvinyl alcohol (Co, Zn-Doped)/n-Si Schottky barrier diodes (SBDs) were investigated in the wide frequency and applied bias voltage ranges at room temperature. Experimental results show that the values of both C and G/ω are strong functions of frequency and applied bias voltage in dark and under illumination (200 W) conditions. It is clear that the dispersion in C and G/ω is considerably high in the depletion and accumulation regions due to illumination induced electron-hole pairs and series resistance (Rs) effect, respectively. The values of C and G/ω exponentially decrease with the increasing frequency and at high frequencies (f>100 kHz) the values of C and G/ω become almost independent of frequency both in dark under illumination.
Recently, sensing, recognition and detection of analytes with chemosensors have become a hot topi... more Recently, sensing, recognition and detection of analytes with chemosensors have become a hot topic of interest in host/guest and supramolecular chemistry. Anion sensing has specially grown to be a major field in the last decades. Therefore, the development of new chromogenic dye sensors or receptors for selective determination of anions has become attractive because of the importance of anions in environmental, biological, and chemical processes. It is widely known that anions like fluoride, acetate, cyanide, chloride, iodide, and phosphate anions are significant in human health. The fluoride, especially, is a biologically important ion because of its role in the treament of dental cavities and osteoporosis. However, excess fluoride can cause serious damage to the thyroid, bones, and the kidneys. The acetate anion also plays a critical role in many metabolic processes, and exhibits specific biochemical behavior on antibodies and enzymes.
Toplumlarin kalkinmasinda vazgecilmez bir oneme sahip olan ilkokul egitimi ve niteligi sorunu Tur... more Toplumlarin kalkinmasinda vazgecilmez bir oneme sahip olan ilkokul egitimi ve niteligi sorunu Turkiye’de II. Mesrutiyetten itibaren tartisilmaya baslanmistir. Toplumsal gelismenin saglanabilmesi icin ilk egitimde okutulan derslerin muhtevasi degistirilmis ve derslere farkli misyonlar yuklenmistir. Cumhuriyetin ilaninin ardindan bu konuda yeni duzenlenmeler yapilmis ve hazirlanan yeni mufredat programlari ile cumhuriyetin kazanimlarina sahip cikacak vatandaslar yetistirilmek istenmistir. Bu amacla hazirlanan 1926 Ilk Mektepler Mufredat Programina eklenen ve icerigi degistirilen Hayat Bilgisi ve Tabiat Dersleri ile ilkokul ogrencilerinin gelecekte saglikli, memleket gerceklerinden haberdar, iktisatli ve modern bir vatandas olarak yetismeleri istenmistir.
Ketorolac (KC) suffers from the general side effects of NSAIDs, owing to presence of free carboxy... more Ketorolac (KC) suffers from the general side effects of NSAIDs, owing to presence of free carboxylic acid group. The study aimed to retard the adverse effects of gastrointestinal origin. Ten prodrugs of KC were synthesized by amidation with ethyl esters of amino acids, namely, glycine, L-phenylalanine, L-tryptophan, L-valine, L-isoleucine, L-alanine, L-leucine, L-glutamic acid, L-aspartic acid and b-alanine. Purified synthesized prodrugs were characterized by m.p., TLC, solubility, partition coefficients, elemental analyses, UV, FTIR, NMR and MS. Synthesized prodrugs were subjected for biopharmaceutical studies, analgesic, anti-inflammatory activities and ulcerogenic index. Marked reduction of ulcerogenic index and comparable analgesic, anti-inflammatory activities were obtained in all cases as compared to KC. Among synthesized prodrugs, viz. AR-11, AR-19 and AR-20 showed excellent pharmacological response and encouraging hydrolysis rate both in SIF and in 80% human plasma. Prodrugs with increased aliphatic side chain length or introduction of aromatic substituent showed enhanced partition coefficient but diminished dissolution and hydrolysis rates. Such prodrugs can be considered for sustained release purpose.
Molecular Crystals and Liquid Crystals, Dec 27, 2011
A new Schiff base complex N-(4-bromobenzylidene)-N′-(2-pyridyl) hydrazine, C12H10N3Br, has been s... more A new Schiff base complex N-(4-bromobenzylidene)-N′-(2-pyridyl) hydrazine, C12H10N3Br, has been synthesized and characterized by elemental analyses, mass, H NMR, ultraviolet–visible (UV–VIS), and IR spectroscopy and single-crystal X-ray determination. The p-Br-benzene and pyridine rings are almost planar and the dihedral angle between the planes is 11.1(3)°. The crystal structure is stabilized by intermolecular N‒H…N‒Py hydrogen bonding interaction. X-ray diffraction analyses show that N-(4-bromobenzylidene)-N′-(2-pyridyl) hydrazine Schiff base molecule crystallizes in the monoclinic system, P21/c space group, a = 5.611(5) Å, b = 19.566(5) Å, c = 10.715(5) Å, β = 98.766(5)°, and V = 1162.60(12) Å.
Dielectric properties and ac electrical conductivity (σ ac ) of Au/PVA(Co, Zn acetate)/n-Si and A... more Dielectric properties and ac electrical conductivity (σ ac ) of Au/PVA(Co, Zn acetate)/n-Si and Au/PVA(Ni, Zn acetate)/n-Si Schottky diodes (SDs) have been investigated in dark and under illumination by using experimental capacitance-voltage (C-V) and conductance-voltage (G/ω-V) measurements at 1 MHz and room temperature. Experimental results indicate that the change in dielectric constant (ε'), dielectric loss (ε''), loss tangent (tanδ), the real (M') and imaginary (M'') parts of electric modulus and ac electrical conductivity (σ ac ) with illumination were found to change linearly with illumination level (P). On the other hand, the ε', ε'', tanδ and σ ac vs P have positive slope while the M' and M'' vs P have negative slope. Such behavior of dielectric properties and σ ac can be attributed to illumination induced electron-hole pairs under illumination effect in the depletion region of SDs. The obtained results under illumination suggest that these devices can be used as a sensor in optical applications.
Amino acid Schiff bases, [NaL]·nH2O (L = N-(2-hydroxy-5-nitrobenzylidene)alaninate, N-(2-hydroxy-... more Amino acid Schiff bases, [NaL]·nH2O (L = N-(2-hydroxy-5-nitrobenzylidene)alaninate, N-(2-hydroxy-5-nitrobenzylidene)valinate, and N-(2-hydroxy-5-nitrobenzylidene)phenylalaninate), were synthesized as monosodium salts (L1Na–L3Na). The structures of the monosodium salts were confirmed on the basis of elemental analysis, conductivity measurements, UV–vis, FT-IR, and 2D NMR (HMQC) spectroscopies. L1Na was also structurally determined by single-crystal X-ray diffraction. Hydrogen bond between the amino N(2)–H and phenolate O(1) of the salicylidene part of the molecule played important roles in stabilizing the zwitterion crystal structure. The ranges of the D–H…A angles and those of the H…A and D…A distances indicated the presence of short hydrogen bonds in the structure. In addition, the monosodium salts have been evaluated for in vitro antioxidant activity. Iron(III) complexes (L1Fe–L3Fe) have been obtained by reaction of the appropriate ligand with iron(III) chloride in a 2 : 1 M ratio. Fe(III) complexes were characterized by elemental and thermal analysis, conductivity and magnetic susceptibility measurements, UV–vis, FT-IR, and X-ray photoelectron spectroscopy methods. Graphical abstract
A new Schiff-base complex 2-{(E)-[2hydroxyphenyl)imino]methyl}phenol has been synthesized and cha... more A new Schiff-base complex 2-{(E)-[2hydroxyphenyl)imino]methyl}phenol has been synthesized and characterized by elemental analyses, UV-VIS and IR spectroscopy and single crystal X-ray determination. The structure comprises two independent and similar molecules. The two independent molecules in the asymmetric unit are hydrogen bonded and have different conformations. In each molecule, C 13 H 11 NO 2 , adopt an E configuration about the azomethine C-N double bond. The complex crystallized in the triclinic space group P-1. Two benzene rings and azomethine group are practically coplanar, as a result of intramolecular hydrogen bonds involving the hydroxy O atom and azomethine N atom. Also hydroxy group of the molecule is the presence intermolecular O-HÁÁÁO hydrogen bonds with the hydroxy group of the other molecule.
Notwithstanding the different names given to science courses, they existed in all primary and mid... more Notwithstanding the different names given to science courses, they existed in all primary and middle school curricula beginning with the first curriculum of the Republic of Turkey released in 1924. In this study, the physics topics included in the middle school science curricula released in
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Jun 1, 2014
ABSTRACT In this work, N-(4-Methylbenzylidene)-N'-(2-carboxyphenyl) hydrazine, C15H14N2O2... more ABSTRACT In this work, N-(4-Methylbenzylidene)-N'-(2-carboxyphenyl) hydrazine, C15H14N2O2, Schiff base molecule has been synthesized and characterized by elemental analyses, UV-Vis and IR spectroscopy and single crystal X-ray determination. The molecule of the title compound adopt an E configuration about the azomethine CN double bond. The benzene and phenyl rings are planar and the dihedral angle between the planes is 7.2(2)°. The crystal structure is stabilized by intermolecular OH⋯O and intramoleculer NH⋯O hydrogen bonding interactions. X-ray diffraction analyses show that, N-(4-Methylbenzylidene)-N'-(2-carboxyphenyl) hydrazine Schiff base molecule crystallizes in the monoclinic system, P21/c space group, a=4.392(5)Å, b=22.340(5)Å, c=13.528(5)Å, β=92.882(5)°, V=1325.7(16)Å(3), Z=4. The conformational analysis of N-(4-Methylbenzylidene)-N'-(2-carboxyphenyl) hydrazine was performed by the density functional theory (DFT) B3LYP method using the 6-311++G(d,p) basis set. Also, theoretical values of FTIR and UV-Vis were performed by the same method. The calculated geometry parameters, IR and UV-Vis results were compared with experimental results.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Erzincan Üniversitesi Eğitim Fakültesi Dergisi, Dec 1, 2009
Öğrencilerde çevreye duyarlı davranışların oluşturulmasında formal eğitimin en önemli öğeleri ola... more Öğrencilerde çevreye duyarlı davranışların oluşturulmasında formal eğitimin en önemli öğeleri olan öğretmenlerin rolü oldukça fazladır. Bu noktada öğrencilerin model olarak aldıkları öğretmenlerin su tüketimi davranışları oldukça önemlidir. Bu nedenle öğretmen yetiştiren kurumlarda, öğretmen adaylarına bilinçli su tüketimi davranışlarının kazandırılması gerekmektedir. Yapılan bu çalışma ile öğretmen adaylarının su tüketimi davranışlarının belirlenmesi ve hatalı olanların düzeltilmesi noktasında bazı öneriler getirilmesi amaçlanmıştır. 2007-2008 öğretim yılı bahar döneminde yapılan araştırmanın örneklemini Atatürk Üniversitesi Kazım Karabekir Eğitim Fakültesi Ortaöğretim Bölümü biyoloji, fizik ve kimya öğretmenliği son sınıfında okuyan 139 öğretmen adayı oluşturmaktadır. Öğretmen adaylarının su tüketimi davranışlarının belirlenmesinde araştırmacılar tarafından geliştirilen ve üçlü likert tipte hazırlanan 13 maddelik "Bilinçli Su Tüketimi Anketi" kullanılmıştır. Çalışma sonucunda öğretmen adaylarının su tasarrufuna fazla dikkat etmedikleri sonucuna varılmıştır. Bununla birlikte adayların su tüketimi davranışlarının cinsiyetlerine, yaşlarına, öğrenim gördükleri bölümlere ve yaşadıkları yerleşim birimlerine göre farklılaşmadığı belirlenmiştir.
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