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2004

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Coalescence Remnant Of Spinning Binary Black Holes, J Baker, M. Campanelli, C. O. Lousto, R. Takahashi Jan 2004

Coalescence Remnant Of Spinning Binary Black Holes, J Baker, M. Campanelli, C. O. Lousto, R. Takahashi

Physics & Astronomy Faculty Publications

We compute the gravitational radiation generated in the evolution of a family of close binary black hole configurations, using a combination of numerical and perturbative approximation methods. We evolve the binaries with spins s aligned or counteraligned with the orbital angular momentum from near the innermost stable circular orbit down to the final single rotating black hole. For the moderately spinning holes studied here the remnant Kerr black holes formed at the end of an inspiral process have rotation parameters a/M≈0.72+0.32(s/mH), suggesting it is difficult (though not excluded) to end up with near maximally rotating holes from such scenarios.

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Publishing Aviation Research: A Literature Review Of Scholarly Journals, Robert W. Kaps, Ed Phillips Jan 2004

Publishing Aviation Research: A Literature Review Of Scholarly Journals, Robert W. Kaps, Ed Phillips

Journal of Aviation/Aerospace Education & Research

The importance of the aviation industry's socio-economic impact, domestically and globally, cannot be denied. In light of this and, as aviation continues to evolve as an academic field of study, post-secondary institutions with aviation specific curriculum have grown,in number and prominence. As a direct consequence of academic growth, the necessity to publish follows as a concomitant requirement. Through the diligence of those researchers actively conducting aviation related research a common theoretical and conceptual base for aviation specific research has been established. The void that once existed for aviation research has been filled, predominantly by three aviation specific journals and a …

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Complete Angular Distribution Measurements Of Two-Body Deuteron Photodisintegration Between 0.5 And 3 Gev, H. Bagdasaryan, H. Bektasoglu, G. E. Dodge, T. A. Forest, C. E. Hyde-Wright, A. Klein, A. V. Klimenko, S. E. Kuhn, F. Sabatié, S. Stepanyan, L. B. Weinstein, J. Yun, Et Al., The Clas Collaboration Jan 2004

Complete Angular Distribution Measurements Of Two-Body Deuteron Photodisintegration Between 0.5 And 3 Gev, H. Bagdasaryan, H. Bektasoglu, G. E. Dodge, T. A. Forest, C. E. Hyde-Wright, A. Klein, A. V. Klimenko, S. E. Kuhn, F. Sabatié, S. Stepanyan, L. B. Weinstein, J. Yun, Et Al., The Clas Collaboration

Physics Faculty Publications

Nearly complete angular distributions of the two-body deuteron photodisintegration differential cross section have been measured using the CEBAF Large Acceptance Spectrometer detector and the tagged photon beam at the Thomas Jefferson National Accelerator Facility. The data cover photon energies between 0.5 and 3.0 GeV and center-of-mass proton scattering angles 10°–160°. The data show a persistent forward-backward angle asymmetry over the explored energy range, and are well described by the nonperturbative quark gluon string model.

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Measurement Of Beam-Spin Asymmetries For Π⁺ Electroproduction Above The Baryon Resonance Region, K. V. Dharmawardane, G. E. Dodge, C. E. Hyde-Wright, S. E. Kuhn, L. M. Qin, F. Sabatié, L. B. Weinstein, J. Yun, Et Al., Clas Collaboration Jan 2004

Measurement Of Beam-Spin Asymmetries For Π⁺ Electroproduction Above The Baryon Resonance Region, K. V. Dharmawardane, G. E. Dodge, C. E. Hyde-Wright, S. E. Kuhn, L. M. Qin, F. Sabatié, L. B. Weinstein, J. Yun, Et Al., Clas Collaboration

Physics Faculty Publications

We report the first evidence for a nonzero beam-spin azimuthal asymmetry in the electroproduction of positive pions in the deep-inelastic kinematic region. Data for the reaction e→pe'π+X have been obtained using a polarized electron beam of 4.3 GeV with the CEBAF Large Acceptance Spectrometer at the Thomas Jefferson National Accelerator Facility. The amplitude of the sin ᵠ modulation increases with the momentum of the pion relative to the virtual photon, z. In the range z = 0.5-0.8 the average amplitude is 0.038 ± 0.005 ± 0.003 for a missing mass Mx > 1.1 GeV and 0.037 …

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The Role Of Well-Being, Joseph Raz Jan 2004

The Role Of Well-Being, Joseph Raz

Faculty Scholarship

"Well-being" signifies the good life, the life which is good for the person whose life it is. I have argued that well-being consists in a wholehearted and successful pursuit of valuable relationships and goals. This view, a little modified, is defended , but the main aim of the article is to consider the role of well-being in practical thought. In particular I will examine a suggestion which says that when we care about people, and when we ought to care about people, what we do, or ought to, care about is their well-being. The suggestion is indifferent to who cares …

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Synthesis And Reactivity Of Tetrahydroimidazo [1,5-B][1,2,4]Oxadiazol- 2(1h)-Thiones, Necdet Coşkun, Fatma Ti̇rli̇ Tat Jan 2004

Synthesis And Reactivity Of Tetrahydroimidazo [1,5-B][1,2,4]Oxadiazol- 2(1h)-Thiones, Necdet Coşkun, Fatma Ti̇rli̇ Tat

Turkish Journal of Chemistry

1,3-Dipolar cycloaddition of imidazoline 3-oxides 1 with methylisothiocyanate proceeds regio- and diastereoselectively to give tetrahydroimidazo[1,5-b][1,2,4]oxadiazol-2(1H)-thiones 3 in high yields. The cis configuration of the adducts was proved by our double cis elimination test as well as by NOESY experiments. Adducts 3a-c undergo ring opening at reflux in acetonitrile to give imidazoles while 3d-e undergo retro dipolar cycloaddition to give the starting nitrones 1d-e. The imidazooxadiazol-2-thiones 3a-e were treated with concentrated HCl in ethanol at 50 °C to give the corresponding 4H-[1,2,4]oxadiazole-5-thione only in cases in which the substituent at C-6 is an aryl.

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Kinetics And Mechanism Of Oxidation Of N--Propanolamine By Dihydroxydiperiodatonickelate(Iv) In Alkaline Medium, Jin-Huan Shan, Jing Qian, Ming-Zhu Gao, Shi-Gang Shen, Han-Wen Sun Jan 2004

Kinetics And Mechanism Of Oxidation Of N--Propanolamine By Dihydroxydiperiodatonickelate(Iv) In Alkaline Medium, Jin-Huan Shan, Jing Qian, Ming-Zhu Gao, Shi-Gang Shen, Han-Wen Sun

Turkish Journal of Chemistry

The kinetics of oxidation of n--Propanolamine (n-PA) by dihydroxy diperiodato-nickelate(IV) (DPN) in alkaline medium was studied with spectrophotometry in a temperature range of 293.2-308.2 K. The reaction was found to be pseudo first-order with respect to DPN and fractional order to n-PA. The rate conatant k_{obs}, rose with an increase in the concentration of OH^{-} and a decrease in the concentration of IO_{4}^{-}. Added salts did not affect the rate and no free radical was detected. From the evaluation of linear data, a reaction mechanism is proposed which involves a pre-equilibrium of an adduct formation between n-PA and dihydroxymonoperiodatonickelate(IV) (MPN), …

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Synthesis, Spectral Characterization And Biological Applications Of Tri- And Diorganotin(Iv) Derivatives Of 2-[N-(2,6-Dichloro-3-Methylphenyl)Amino]Benzoic Acid, Sohail Mahmood, Saqib Ali, Moazzam Hussain Bhatti, Mohammad Mazhar, Khadija Shahid, Khalid Mohammed Khan, Ghulam Mustafa Maharvi Jan 2004

Synthesis, Spectral Characterization And Biological Applications Of Tri- And Diorganotin(Iv) Derivatives Of 2-[N-(2,6-Dichloro-3-Methylphenyl)Amino]Benzoic Acid, Sohail Mahmood, Saqib Ali, Moazzam Hussain Bhatti, Mohammad Mazhar, Khadija Shahid, Khalid Mohammed Khan, Ghulam Mustafa Maharvi

Turkish Journal of Chemistry

A series of tri- and diorganotin(IV) compounds with the general formulae R_{3}SnL and R_{2}SnL_{2} (where R = Me, n-Bu, Ph and L = 2-[N-(2,6-dichloro-3-methylphenyl)-amino]benzoate) were synthesized. These compounds were characterized by different instrumental methods such as infrared, multinuclear NMR (^{1}H, ^{13}C, ^{119}Sn) and mass spectrometry. The spectroscopic investigation illustrates that the carboxylate group acts as a bidentate in solid state and as a monodentate in solution. Biological screening tests reveal that the investigated compounds have potential as antibacterial agents.

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One Step Synthesis And Some Reactions Of 7-Hydrazino-3,4-Diphenyl- 2h-Pyrazolo [3,4-D] Pyridazine, Ahmet Şener Jan 2004

One Step Synthesis And Some Reactions Of 7-Hydrazino-3,4-Diphenyl- 2h-Pyrazolo [3,4-D] Pyridazine, Ahmet Şener

Turkish Journal of Chemistry

The 7-hydrazino-3,4-diphenyl-2H-pyrazolo-[3,4-d]-pyridazine 3, obtained in 2 different ways consisting of the reactions of anhydrous hydrazine with 4-benzoyl-5-phenyl-2,3-dihydro-2,3-furandione 1 or 3,4-diphenyl-2H-pyrazolo-[3,4-d]-pyridazin-7(6H)-one 2, was converted into hydrazone derivatives 4 by the reactions of 3 with various salicylaldehydes.

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Ftir And Ft-Raman Spectral Investigations On 4-Aminoquinaldine And 5-Aminoquinoline, N. Puviarasan, V. Arjunan, S. Mohan Jan 2004

Ftir And Ft-Raman Spectral Investigations On 4-Aminoquinaldine And 5-Aminoquinoline, N. Puviarasan, V. Arjunan, S. Mohan

Turkish Journal of Chemistry

The FTIR spectra of 4-aminoquinaldine and 5-aminoquinoline were recorded in solid phase on a Bruker IFS 66V spectrometer in the region 4000--400 cm^{-1}. The FT-Raman spectra of these compounds were also recorded in the same instrument with a FRA 106 Raman module. The molecules under investigation are considered to have a C_{S} point group by assuming the --NH_{2} and --CH_{3} groups as point masses. All the vibrations are both IR and Raman active. The simple general valance force field (SGVFF) is adopted for both inplane and out of plane vibrations. All the frequencies are assigned in terms of fundamentals, overtones …

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Determination Of ^{90}Sr Accumulation In Human Teeth, Recep Acar, Orhan Acar Jan 2004

Determination Of ^{90}Sr Accumulation In Human Teeth, Recep Acar, Orhan Acar

Turkish Journal of Chemistry

The accumulation of ^{90}Sr in decayed or exfoliated human teeth was investigated by ultra low level beta counting. Fuming nitric acid and the necessary carriers and reagents were used for dissolving the samples, and the separation and purification of ^{90}Sr. The Ca contents of samples were determined by flame atomic absorption spectrometry with Zeeman-effect background correction. A mixture of K and La used as a matrix modifier was found to be preferable for the determination of Ca in samples. The optimum concentration and concentration ratio of K and La on the absorbance of Ca in the NIST certified reference material, …

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^{1}H, ^{13}C, ^{119}Sn Nmr, Mass, Mössbauer And Biological Studies Of Tri-,Di- And Chlorodiorganotin(Iv) Carboxylates, Hajra Masood, Saqib Ali, Mohummad Mazhar, Saira Shahzadi, Khadija Shahid Jan 2004

^{1}H, ^{13}C, ^{119}Sn Nmr, Mass, Mössbauer And Biological Studies Of Tri-,Di- And Chlorodiorganotin(Iv) Carboxylates, Hajra Masood, Saqib Ali, Mohummad Mazhar, Saira Shahzadi, Khadija Shahid

Turkish Journal of Chemistry

The reaction of 2-[(2,3-dimethylphenyl)amino]benzoic acid (HL) with tri- and diorganotin(IV) chlorides yielded complexes of the type R_{3}SnL and R_{2}SnL_{2} (R = n-C_{4}H_{9}, C_{6}H_{5}, C_{6}H_{5}CH_{2}, n-C_{8}H_{17}). The compounds R_{2}SnClL were obtained by a redistribution reaction between R_{2}SnL_{2} and R_{2}SnCl_{2}. All the compounds were characterized by CHN analysis, infrared, multinuclear NMR, mass and Mössbauer spectroscopy. The possible mode of carboxylate group bonding in solid as well as in solution is proposed on the basis of infrared, Mössbauer and NMR (^{1}H, ^{13}C, ^{119}Sn) spectroscopy.

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Synthesis And Antimicrobial Activity Of Some Pyridyl And Naphthyl Substituted 1,2,4-Triazole And 1,3,4-Thiadiazole Derivatives, Khosrow Zamani, Khalil Faghihi, Taraneh Tofighi, Mohammad Reza Shariatzadeh Jan 2004

Synthesis And Antimicrobial Activity Of Some Pyridyl And Naphthyl Substituted 1,2,4-Triazole And 1,3,4-Thiadiazole Derivatives, Khosrow Zamani, Khalil Faghihi, Taraneh Tofighi, Mohammad Reza Shariatzadeh

Turkish Journal of Chemistry

Synthesis of new 1,2,4-tri and 1,3,4-thiadiazoles, bearing isomeric pyridyl and 1-naphthyl is reported using 1,4-disubstituted thiosemicarbazides in alkaline and acidic media, respectively. The methylthio and benzylthio derivatives of the synthesized triazoles are also reported. All of the synthesized compounds were characterized by their FT-IR, ^{1}H-NMR and mass spectral data. The antibacterial studies of some of the synthesized compounds against S. aureus} and E. coli} as MIC values are reported. None of them have important antibacterial activities.

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Acylated Iridoid Glycosides From Verbascum Lasianthum, Zeli̇ha Ş. Akdemi̇r, İ. İrem Tatli, Erdal Bedi̇r, Ikhlas A. Khan Jan 2004

Acylated Iridoid Glycosides From Verbascum Lasianthum, Zeli̇ha Ş. Akdemi̇r, İ. İrem Tatli, Erdal Bedi̇r, Ikhlas A. Khan

Turkish Journal of Chemistry

From the roots of Verbascum lasianthum Boiss. ex Bentham 4 catalpol derivatives, 6-O-(\alpha-L-rhamnopyranosyl)-catalpol (1), verbascoside A [= 6-O-(4''-O-trans-p-methoxycinnamoyl)-\alpha -L-rhamnopy- ranosylcatalpol] (2), pulverulentoside I [= 6-O-(3''-O-acetyl-2''-O-trans-p-methoxycinnamoyl)-\alpha -L-rham-nopyranosylcatalpol] (3), and buddlejoside A_{5} [= 6-O-(2''-O-acetyl-3''-O-trans-p-methoxycinnamoyl)-\alpha -L-rhamnopyranosylcatalpol] (4), as well as aucubin (5) and an aucubin derivative, unduloside III [= 6-O-(3''-O-trans-p-methoxycinnamoyl)- \alpha-L-rhamnopyranosylaucubin] (6), were isolated and characterized. The structure elucidation of the compounds was established on the basis of spectroscopic evidence. Buddlejoside A_{5} (4) was found for the first time in the genus Verbascum.

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Saponin, Iridoid, Phenylethanoid And Monoterpene Glycosides From Verbascum Pterocalycinum} Var. Mutense, İ. İrem Tatli, Zeli̇ha Ş. Akdemi̇r, Erdal Bedi̇r, Ikhlas A. Khan Jan 2004

Saponin, Iridoid, Phenylethanoid And Monoterpene Glycosides From Verbascum Pterocalycinum} Var. Mutense, İ. İrem Tatli, Zeli̇ha Ş. Akdemi̇r, Erdal Bedi̇r, Ikhlas A. Khan

Turkish Journal of Chemistry

Ilwensisaponin C (= 3-O-{[\alpha-L-rhamnosyl-(1 \to 4)-(\beta-D-glucopyranosyl-(1 \to 3)]-\beta-D-glucopyranosyl]-(1 \to 2)-\beta-fucopyranosyl}-11-methoxy-olean-12-ene-3\beta, 23, 28-triol) (1), ilwensisaponin A (= mimengoside A = 3-O-{[\alpha-L-rhamnosyl-(1 \to 4)-(\beta-D-glucopyranosyl-(1 \to 3)]-\beta -D-glucopyranosyl]-(1 \to 2)-\beta-fucop- yranosyl}-13\beta, 28-epoxyolean-11-ene-3\beta, 23-diol) (2), ajugol (3), picroside IV (= 6^\prime-O-trans- p-hydroxycin- namoylcatalpol) (4), verbascoside {= acteoside, [\beta -(3,4-dihydroxyphenyl)-ethyl]-(3^{\prime-O-\alpha-L-rhamnopyra- nosyl)-(4^{\prime-O-caffeoyl)-\beta-D-glucopyranoside} (5) and 1-(\beta -D-glucopyranosyl)-8-hydroxy-3, 7-dimethyl-oct-2(E), 6(E)- dienoate (6) were isolated from the flowers of Verbascum pterocalycinum var. mutense Hub.-Mor. The structures of the compounds were determined primarily from 1D and 2D NMR experiments. This is the first phytochemical study performed on V. pterocalycinum var. mutense and the first report of the presence of 1-(\beta …

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Synthesis Of Some New Pyridylethylated Benzoxa(Thia)Zolinones With Analgesic Activitiy, Nesri̇n Gökhan, Göknur Aktay, Hakki Erdoğan Jan 2004

Synthesis Of Some New Pyridylethylated Benzoxa(Thia)Zolinones With Analgesic Activitiy, Nesri̇n Gökhan, Göknur Aktay, Hakki Erdoğan

Turkish Journal of Chemistry

Eighteen new 3-[2-(2-/4-pyridyl)ethyl]benzoxazolinone (benzothiazolinone) derivatives were synthesized by reacting 2-/4-vinylpyridine and appropriate benzoxazolinones and benzothiazolinones. The analgesic activities of these compounds were investigated by modified Koster and hot-plate tests. Test results revealed that most of the compounds at 100 mg/kg dose levels have higher analgesic activities than acetylsalicylic acid. Compounds with bromo substituents on the phenyl ring in the 6-position of the main ring seemed to show less activity than those with fluorinated ones. Compound 6b showed remarkably high activity in the hot-plate test, although it was inactive in the Koster test. However compound 3a had statistically significant high peripheral …

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Chemical Constituents Of Linaria Aucheri, Di̇lek Erci̇l, M. Koray Sakar, Esther Del Olmo, Arturo San Feliciano Jan 2004

Chemical Constituents Of Linaria Aucheri, Di̇lek Erci̇l, M. Koray Sakar, Esther Del Olmo, Arturo San Feliciano

Turkish Journal of Chemistry

From the petroleum ether and methanol extracts of the aerial parts of Linaria aucheri (Scrophulariaceae) 6 known compounds: \beta-amyrin (1), ergost-7-en-3\beta-ol (2), stigmasta-5,22- E-dien-3\beta -ol (3), stigmast-5-en, 24S-3\beta-ol (4), antirrinoside (5) and linariin (6), were isolated and identified. The structures of these compounds have been elucidated by spectroscopic methods (UV, IR, ^{1}H NMR, ^{13}C NMR, DEPT-135 and GC-MS).

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Cationic Rearrangements Of An Endo}-Cyclopropyl Methanol System Incorporated In A Benzonorbornadiene System, Abdullah Menzek, Melek Karakaya Jan 2004

Cationic Rearrangements Of An Endo}-Cyclopropyl Methanol System Incorporated In A Benzonorbornadiene System, Abdullah Menzek, Melek Karakaya

Turkish Journal of Chemistry

Chloride 18 (47%) and alcohol 21 (44%) were isolated from the reaction of alcohol 20 with SOCl_2. Cyclopropylcarbinyl -- cyclopropylcarbinyl rearrangement leads to chloride 22, which hydrolyses on separation to give alcohol 21. Chloride 18 results from cyclopropyl -- allylcarbinyl rearrangement, followed by a 1,2 -- aryl shift (sequential rearrangement). Syntheses of compounds 23 and 24 support the structures. The behaviour of 20 differs from that of exo isomer 14, probably due to the nature of the intermediates in these reactions.

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Synthesis And Some Reactions Of 4-Benzoyl-5-Phenyl-1-(2,4,6-Trichloro Phenyl)-1h-Pyrazole-3-Carboxylic Acid, Ahmet Şener, İshak Bi̇ldi̇ri̇ci̇ Jan 2004

Synthesis And Some Reactions Of 4-Benzoyl-5-Phenyl-1-(2,4,6-Trichloro Phenyl)-1h-Pyrazole-3-Carboxylic Acid, Ahmet Şener, İshak Bi̇ldi̇ri̇ci̇

Turkish Journal of Chemistry

Furandione 1 was reacted with 2,4,6-trichlorophenylhydrazine to give the 1H-pyrazole-3-carboxylic acid 2 together with a new pyridazinone derivative 3. Then 2 was converted into the corresponding ester 5 or amide 6 derivatives, respectively, via reactions of its acid chloride 4 with various alcohols or N-nucleophiles. Nitrile derivative 7 was obtained by dehydration of 6a in a mixture of SOCl_2 and DMF. Condensation reactions of 2 with some hydrazines led to the formation of pyrazolo [3,4-d] pyridazinone 8 derivatives.

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Chalcogeno Ureas Derived From Bis(1,3-Diazepan-2-Ylidene), Yetki̇n Gök, Engi̇n Çeti̇nkaya Jan 2004

Chalcogeno Ureas Derived From Bis(1,3-Diazepan-2-Ylidene), Yetki̇n Gök, Engi̇n Çeti̇nkaya

Turkish Journal of Chemistry

A series of new electron rich olefins (=\overset{ } CNR(CH_2)_4\overset{ }NR)_2, 3, (a; R = CH_2C_6H_5, b; R = CH_2C_6H_4-OMe-p, c; R = CH_2C_6H_4-NMe_2-p) was generated via the condensation of RNH(CH_2)_4NHR with Me_2NCH (OMe)_2. The C=C bond cleavage reactions of 3 with S_8 and Se provide a simple and straightforward method for the synthesis of 1,3-diazepan-2-chalcogenones 4 and 5, respectively.

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Mechanical And Light Transmittance Properties Of Locust Bean Gum Based Edible Films, Meltem Aydinli, Mehmet Tutaş, Ö. Altan Bozdemi̇r Jan 2004

Mechanical And Light Transmittance Properties Of Locust Bean Gum Based Edible Films, Meltem Aydinli, Mehmet Tutaş, Ö. Altan Bozdemi̇r

Turkish Journal of Chemistry

The behavior of locust bean gum (LBG) under heat was investigated by thermogravimetric (TG), differential thermogravimetric (DTG) and differential scanning calorimetric (DSC) methods. It was observed from the TG, DTG and DSC curves that LBG does not melt and is stable up to 300 °C, although exothermic degradation occurs at higher temperatures. The effect of the amount and molecular weight of polyethylene glycol (PEG) on the light transmittance and mechanical properties of these edible films was also examined. Haze increased and the luminous transmittance and total light transmittance values decreased with both the quantity and molecular weight of PEG. On …

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The Synthesis Of Substituted 4,4'-Thiobis(Aminophenylglyoxime) And Their Polymeric Metal Complexes With Cu(Ii), Ni(Ii) And Co(Ii) Salts, Ahmet Coşkun, İbrahi̇m Karataş Jan 2004

The Synthesis Of Substituted 4,4'-Thiobis(Aminophenylglyoxime) And Their Polymeric Metal Complexes With Cu(Ii), Ni(Ii) And Co(Ii) Salts, Ahmet Coşkun, İbrahi̇m Karataş

Turkish Journal of Chemistry

4,4'-Bis(chloroacetyl)diphenyl thioether (HL) was synthesized from chloroacetyl chloride and diphenyl thioether in the presence of AlCl_3 as catalyst in a Friedel-Crafts reaction. Subsequently, its keto oxime (H_2L) and glyoxime (H_4L) derivatives were also prepared. Then 3 new substituted 4,4'-thiobis(aminophen- ylglyoxime) (H_4L^{1 - 3}) were synthesized from 4,4'-thiobis(chlorophenylglyoxime) and the corresponding amines. The Ni(II), Cu(II) and Co(II) complexes of these ligands were prepared. The structures of these ligands and their complexes were identifed by FT-IR, ^1H NMR and ICP-AES spectral data, elemental analyses and magnetic measurements.

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Determination Of Trace Amounts Of Iodide By An Inhibition Kinetic Spectrophotometric Method, Ramazan Gürkan, Ni̇lgün Bi̇çer, M. Hi̇kmet Özkan, Mehmet Akçay Jan 2004

Determination Of Trace Amounts Of Iodide By An Inhibition Kinetic Spectrophotometric Method, Ramazan Gürkan, Ni̇lgün Bi̇çer, M. Hi̇kmet Özkan, Mehmet Akçay

Turkish Journal of Chemistry

In this study, the reaction between Co(III)-EDTA and hypophosphite ion, catalyzed by Pd(II), was chosen as the indicator reaction. The inhibition kinetics of this catalytic reaction were investigated in the presence of iodide ion and the possibility of its analytical application was evaluated. Catalyzers other than PdCl_2 (Pt, Au and Ni salts) were assayed for the indicator reaction and it was observed that these catalysts have no effect on the reaction. The important variables that affected the reaction rate were investigated and the optimum conditions giving maximum sensitivity were established. The calibration graph, prepared following the inhibition kinetic method, gave …

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Sorption Preconcentration And Determination Of Molybdenum(Vi) By Diffuse Reflection Spectroscopy, Olga N. Kononova, Sergey V. Kachin, Anastasiya E. Chaikovskaya, Alexander G. Kholmogorov, Olga P. Kalyaki̇na Jan 2004

Sorption Preconcentration And Determination Of Molybdenum(Vi) By Diffuse Reflection Spectroscopy, Olga N. Kononova, Sergey V. Kachin, Anastasiya E. Chaikovskaya, Alexander G. Kholmogorov, Olga P. Kalyaki̇na

Turkish Journal of Chemistry

The present work focuses on the preconcentration of molybdenum and its determination in aqueous solutions by means of diffuse reflection spectroscopy. The preconcentration of Mo(VI) was carried out using the macroporous strong basic anion exchanger AV-17-10P synthesized on the basis of styrene and divinylbenzene. The method for Mo determination with this collector in industrial solutions and natural water was developed using solid-phase spectroscopy. The colored surface compound to be determined was obtained by a preceding Mo(VI) sorption on the resin and by subsequent treatment of the concentrate obtained with definite amounts of pyrocatechol violet. The calibration curve is linear at …

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Determination Of Fluoride In Various Samples And Some Infusions Using A Fluoride Selective Electrode, Şeri̇fe Tokalioğlu, Şenol Kartal, Uğur Şahi̇n Jan 2004

Determination Of Fluoride In Various Samples And Some Infusions Using A Fluoride Selective Electrode, Şeri̇fe Tokalioğlu, Şenol Kartal, Uğur Şahi̇n

Turkish Journal of Chemistry

The determination of fluoride in some environmental samples was performed using a fluoride ion-selective electrode. Fluoride concentrations were determined in drinking waters (from different provinces, districts and villages in Turkey), fruit juices, bottled water samples, toothpastes and tooth powders, liquors of Turkish coffee, coffee, linden, rose hip, and various brand tea infusions, and dust samples collected from the Erciyes University campus car park. The average fluoride concentration in 39 drinking waters was 0.21 mg L^{-1} (0.02--1.42 mg L^{-1}); the level of dissolved fluoride in the dust samples was 1.39 \pm 0.09 \mu g g^{-1}; the fluoride concentrations in liquors taken …

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The Effect Of Cultural Conditions On The Variations Of Sod, Cat And Gsh-Px Activities And Lpo Levels In The Filamentous Fungus Fusarium Equiseti, Hülya Ayar Kayali, Leman Tarhan Jan 2004

The Effect Of Cultural Conditions On The Variations Of Sod, Cat And Gsh-Px Activities And Lpo Levels In The Filamentous Fungus Fusarium Equiseti, Hülya Ayar Kayali, Leman Tarhan

Turkish Journal of Chemistry

The changes in the activity of cellular detoxifying defence enzymes such as SOD, CAT and GSH-Px against superoxide anion radical and hydrogen peroxide, and in LPO levels in the filamentous fungus, Fusarium equiseti were measured under growth condition. Experiments were performed comparing changes in glycerol and saccharose (5-25 g/L) as carbon sources, and in glycine, peptone (5-35 g/L) as nitrogen sources in an AFM medium. While SOD activities correlate well with respect to the increase in the glycerol concentration (r = 0.437, p < 0.001), CAT activities showed negative correlation (r = -0.663, p < 0.001). The increase in SOD and CAT activities of F. equiseti correlated with increases in saccharose concentration. When glycerol and saccharose were used as carbon sources, the maximum SOD, CAT and GSH-Px enzymes activities and the minimum LPO level were determined in the medium containing 15 g/L of saccharose on the 12^{th} day at 66.61, 182.79, 1.045 IU/mg and 1.41 nmol MDA/ gr wet weight, respectively. The effects of peptone and glycine as nitrogen sources were also investigated: 53.4% and 48.03% decreases were observed in the SOD and CAT activities of F. equiseti in the presence of 10 g/L of peptone in the culture medium. The presence of 15 g/L of glycine caused 5.30% and 69.90% decreases in the SOD and CAT activities in comparison to the presence of 15 g/L of saccharose, respectively. On the other hand, LPO levels increased in proportion to the decrease in antioxidant enzyme activities in glycine and peptone supplemented media.

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3-Hydroxy Fatty Acids From The Flowers Of Hypericum Lysimachioides Var. Lysimachioides, Hasan Çeti̇n Özen, Mehmet Başhan, Zuhal Toker, Cumali̇ Keski̇n Jan 2004

3-Hydroxy Fatty Acids From The Flowers Of Hypericum Lysimachioides Var. Lysimachioides, Hasan Çeti̇n Özen, Mehmet Başhan, Zuhal Toker, Cumali̇ Keski̇n

Turkish Journal of Chemistry

Fatty acid methyl esters in the leaves and flowers of Hypericum lysimachioides var. lysimachioides (Guttiferae) were analyzed by gas chromatography and gas chromatography-mass spectrometry. The flowers of H. lysimachioides var. lysimachioides produced unusual 3-hydroxy fatty acids [3-hydroxy- tetradecanoic acid (3-OH-C14:0) and 3-hydroxy-octadecanoic acid (3-OH-C18:0)], along with other normal fatty acids. Major components were linolenic and palmitic acids for both leaves and flowers.

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Synthesis, Characterization Of Some Co(Iii) Complexes With Vic-Dioxime Ligands And Their Antimicrobial Properties, Erdal Canpolat, Mehmet Kaya, Seher Gür Jan 2004

Synthesis, Characterization Of Some Co(Iii) Complexes With Vic-Dioxime Ligands And Their Antimicrobial Properties, Erdal Canpolat, Mehmet Kaya, Seher Gür

Turkish Journal of Chemistry

In this study, 6 different new vic-dioxime ligands and their mononuclear complexes with Co(III) have been synthesized. The structures of these compounds were identified by using elemental analyses, IR, ^{1}H and ^{13}C NMR, electronic spectra, magnetic susceptibility measurements and conductivity. In addition, the thermal characterizations and antimicrobial activities of the ligands and their complexes have been investigated.

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Flame Atomic Absorption Spectrometric Determination Of Manganese In Alloys After Preconcentration Onto Amberlite Xad-4 Loaded With Saccharomyces Carlsbergensis, Sitki Baytak, A. Rehber Türker Jan 2004

Flame Atomic Absorption Spectrometric Determination Of Manganese In Alloys After Preconcentration Onto Amberlite Xad-4 Loaded With Saccharomyces Carlsbergensis, Sitki Baytak, A. Rehber Türker

Turkish Journal of Chemistry

A sensitive and simple enrichment method using microorganisms as an adsorbent is described for the determination of trace manganese in alloys. Manganese was determined by flame atomic absorption spectrometry after preconcentration onto Amberlite XAD-4 loaded with Saccharomyces carlsbergensis. The optimum values of pH, amount of adsorbent, amount of microorganism, eluent type and volume of sample solution were determined for the quantitative recovery (>95%) of manganese. Results have been compared with those obtained without using microorganisms. Under optimum conditions, recoveries were 98 \pm 3% with microorganisms and 68 \pm 2% without microorganisms for manganese at a 95% confidence level. The …

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Cover And Contents Jan 2004

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.

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