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Articles 11071 - 11100 of 12081
Full-Text Articles in Entire DC Network
Some Results On Derivation Groups, Murat Alp
Some Results On Derivation Groups, Murat Alp
Turkish Journal of Mathematics
In this paper we describe a share package XMOD of functions for computing with finite, permutation crossed modules, their morphisms and derivations; cat$^1$-groups, their morphisms and their sections, written using the GAP \cite{GAP} group theory programming language. We also give some mathematical results for derivations. These results are suggested by the output produced by the XMOD package.
Strongly Prime Ideals In Cs-Rings, Gonca Güngöroğlu
Strongly Prime Ideals In Cs-Rings, Gonca Güngöroğlu
Turkish Journal of Mathematics
We study and characterize strongly prime right ideals in CS-rings.
On Non-Homogeneous Riemann Boundary Value Problem, Kadi̇r Kutlu
On Non-Homogeneous Riemann Boundary Value Problem, Kadi̇r Kutlu
Turkish Journal of Mathematics
In this paper we consider non-homogeneous Riemann boundary value problem with unbounded oscillating coefficients on a class of open rectifiable Jordan curve.
A Remark On The Asymptotic Properties Of Positive Homogeneous Maps On Homogeneous Lattices, Alp Eden
A Remark On The Asymptotic Properties Of Positive Homogeneous Maps On Homogeneous Lattices, Alp Eden
Turkish Journal of Mathematics
An abstract version of Lyapunov exponents is defined for positive homogeneous maps on Homogeneous Lattices and a sufficient condition is given for the asymptotic stability of the map.
Multipliers Between Orlicz Sequence Spaces, P. B. Djakov, M. S. Ramanuan
Multipliers Between Orlicz Sequence Spaces, P. B. Djakov, M. S. Ramanuan
Turkish Journal of Mathematics
Let $M, N $ be Orlicz functions, and let $D(\ell_M , \ell_N ) $ be the space of all diagonal operators (that is multipliers) acting between the Orlicz sequence spaces $\ell_M$ and $\ell_N$. We prove that the space of multipliers $D(\ell_M , \ell_N )$ coincides with (and is isomorphic to) the Orlicz sequence space $ \ell_{M_N^{*}} ,$ where $ M_N^{*} $ is the Orlicz function defined by $M_N^{*}(\lambda ) = \sup \{ N(\lambda x) - M(x), \; x \in (0,1) \}$.
Cover And Contents
Turkish Journal of Veterinary & Animal Sciences
No abstract provided.
Cover And Contents
Turkish Journal of Veterinary & Animal Sciences
No abstract provided.
Cover And Contents
Turkish Journal of Veterinary & Animal Sciences
No abstract provided.
Synthetic Metal Alloys: Preparation Of Polyaniline/Polypyrrole Alloys In Protic Medium, Fati̇h Köleli̇, Meltem Düdükcü, Yasemi̇n Arslan
Synthetic Metal Alloys: Preparation Of Polyaniline/Polypyrrole Alloys In Protic Medium, Fati̇h Köleli̇, Meltem Düdükcü, Yasemi̇n Arslan
Turkish Journal of Chemistry
Pyrrole and aniline solutions were mixed in different ratios and oxidized under anodic conditions on Pt surface in protic medium. The electrocopolymerization and electrochemical properties of these alloys were investigated. Current-potential diagrams of polyaniline (PA), polypyrrole (PP) and the resulting alloys were recorded and their electrochemical characterizations were identified. In-situ resistance measurements of synthesized alloys were carried out with a home-made apparatus. Conductivity of alloys showed changes depending on applied potential as intrinsic polymers. The electrochemical behaviour of homopolymers and alloys was studied at different temperatures.
A Convenient Synthesis Of Some 4-(Alkylamino)-4,5-Dihydro-1h-1,2,4-Triazol-5-Ones, Bahi̇tti̇n Kahveci̇, Aykut İki̇zler
A Convenient Synthesis Of Some 4-(Alkylamino)-4,5-Dihydro-1h-1,2,4-Triazol-5-Ones, Bahi̇tti̇n Kahveci̇, Aykut İki̇zler
Turkish Journal of Chemistry
A series of 3-alkyl-4-(arylidenamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones, {\bfseries 6-10,} was obtained from the reaction of the corresponding 3-alkyl-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones, {\bfseries 1,} with the appropriate aldehydes. 3-alkyl-4-(alkylamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones of type {\bfseries 11-16} were synthesized from the selective reduction of compounds {\bfseries 5-10} with NaBH$_{4}$ in diglyme or DMSO medium as a general and convenient method.
Investigation Of The Synthesis Of Some Dehydroalanine Derivatives, Si̇bel Süzen, John Michael Williams
Investigation Of The Synthesis Of Some Dehydroalanine Derivatives, Si̇bel Süzen, John Michael Williams
Turkish Journal of Chemistry
Dehydroamino acids represent an important class of compound as they are key intermediates in unusual amino acid and in the design of peptides and are constituents of a variety of naturally occurring antibiotic and phytotoxic peptides. In view of the importance of proteins and peptides containing hydroxyamino acids and the problems associated with their synthesis and dehydration, an investigation was performed on model compounds in order to examine the difficulties of the dehydration reactions. The preparation and properties of the model dehydroalanine derivatives have been studied.
X-Ray Powder Diffraction And Ir Study Of Calcium Borophosphate Cabpo_5, A. Baykal, G. Gözel, Meral Kizilyalli, M. Toprak, R. Kniep
X-Ray Powder Diffraction And Ir Study Of Calcium Borophosphate Cabpo_5, A. Baykal, G. Gözel, Meral Kizilyalli, M. Toprak, R. Kniep
Turkish Journal of Chemistry
In this study, CaBPO_5 was synthesized by different solid state reactions than reported before and its X-ray powder diffraction and IR data were reported. In one of these solid state reactions BPO_4 was used as a phosphating agent. The examination of the X-ray powder diffraction data showed that this compound crystallized in a hexagonal system and the refined unit cell parameters were a = 6.684, c = 6.616(2) \AA, with Z=3 as reported before. From the observed reflections, the space group was determined as P3_121, and its density was found to be 3.15 g/cc. The X-ray powder diffraction and IR …
Ion-Selective Membrane Electrode For The Determination Of A Novel Phenylpiperazine Antidepressant, Nefazodone, Arzum Erdem, Di̇lşat Özkan, Kağan Kerman, Burcu Meri̇ç, Tayfun Dalbasti, Mehmet Özsöz
Ion-Selective Membrane Electrode For The Determination Of A Novel Phenylpiperazine Antidepressant, Nefazodone, Arzum Erdem, Di̇lşat Özkan, Kağan Kerman, Burcu Meri̇ç, Tayfun Dalbasti, Mehmet Özsöz
Turkish Journal of Chemistry
The construction and performance characteristics of ion-selective membrane electrodes for a newly found phenylpiperazine antidepressant, Nefazodone (NFN), based on its ion-pair complexes with phosphotungstate (PT), tetraphenylborate (TPB), tungstosilicate (TS) and reineckate (RN) in a poly(vinyl chloride) (PVC) matrix are described. The best ion-selective electrode for determination of NFN contains NFN-PT as the active material. This electrode exhibits a Nernstian response (62.6 ± 0.4 mV per decade) in the range 1.5 x 10$^{-5}$ to 1.0 x 10^{-2} M NFN.HCl in solutions. The selectivity of this electrode to NFN in the presence of a number of sugar molecules, cations and drugs is …
Zinc Determination In Pleural Fluid, Nazan Demi̇r, Yaşar Demi̇r, Ebubeki̇r Bakan, İrfan Küfrevi̇oğlu
Zinc Determination In Pleural Fluid, Nazan Demi̇r, Yaşar Demi̇r, Ebubeki̇r Bakan, İrfan Küfrevi̇oğlu
Turkish Journal of Chemistry
In this study, an enzymatic zinc determination method was applied to pleural fluid, the basis of which was the regaining of the activity of apo carbonic anhydrase by the zinc present in the sample. The method was used for pleural fluid zinc determination in order to show the application to body fluids other than serum. For this purpose, pleural fluids were obtained from 20 patients and zinc concentrations were determined. Carbonic anhydrase was purified by affinity chromatography from bovine erythrocytes. The zinc present in its structure was removed by dialysis against dipicolinic acid, resulting in apoenzyme obtained at a ratio …
All Solid-State Contact Lead(Ii) Ion-Selective Pvc Membrane Electrode Using Dimethylene Bis(4-Methylpiperidinedithiocarbamate) Neutral Ionophore, İbrahi̇m Işildak
All Solid-State Contact Lead(Ii) Ion-Selective Pvc Membrane Electrode Using Dimethylene Bis(4-Methylpiperidinedithiocarbamate) Neutral Ionophore, İbrahi̇m Işildak
Turkish Journal of Chemistry
All solid-state contact PVC membrane electrodes for lead(II) ion were developed by using dimethylene bis(4-methylpiperidinedithiocarbamate) as neutral carrier and nitrophenyloctyl ether or dioctylsebacate as plasticizers. Response properties of the all solid-state contact PVC membrane electrode prepared with nitrophenyloctyl ether were better than those of the membrane electrode prepared with dioctylsebacate. The nitrophenyloctyl ether plasticized the all solid-state contact PVC membrane electrode and exhibited a good linear response of 30 mV/decade for lead(II) ion within the concentration ranges \( 0.1-5\times10^{-6} \) mol dm\( ^{-3} \) lead(II) nitrate, good selectivity over alkali, alkali-earth and transition metal ions including copper(II) ion by a …
Electrothermal Atomic Absorption Spectrometric Determination Of Nickel After Its Flotation Enrichment By Iron(Iii) Hexamethylenedithiocarbamate, Trajce Stafilov, Gorica Pavlovska, Katarina Cundeva
Electrothermal Atomic Absorption Spectrometric Determination Of Nickel After Its Flotation Enrichment By Iron(Iii) Hexamethylenedithiocarbamate, Trajce Stafilov, Gorica Pavlovska, Katarina Cundeva
Turkish Journal of Chemistry
Abstract. Nanogram quantities of nickel were removed from 1 L samples of dilute aqueous solutions by coflotation. A mixture of hydrated iron(III) oxide (Fe_2O_3\( \cdot \)xH_2O) and iron(III) hexamethylene-dithiocarbamate (Fe(HMDTC)_3) served as collectors. After flotation separation from the mother liquor, the solid sublate containing nickel traces was dissolved and the analyte was determined by electrothermal atomic absorption spectrometry (ETAAS). All important parameters necessary for the successful collection of nickel were checked. The results of nickel ETAAS analysis in tap and spring waters were compared with inductively coupled plasma-atomic emis-sion spectrometric measurements (ICP-AES). The limit detection of nickel by the ETAAS …
Investigation Of The Influence Of Thiocarbamide In The Process Of Carbamide Deparaffinization, Sevi̇l Veli̇yeva
Investigation Of The Influence Of Thiocarbamide In The Process Of Carbamide Deparaffinization, Sevi̇l Veli̇yeva
Turkish Journal of Chemistry
The influence of thiocarbamide in the process of carbamide dewaxing was investigated. The dependence of separated paraffins on the quantity of thiocarbamide was examined experimentally. It was determined that the separation of paraffins becomes equal to zero when moles of carbamide and thiocarbamide in water-isopropyl alcohol solution are equal. The low-temperature qualities (the temperature of dimness and freezing) of dewaxed fuels were also examined. By using infrared spectroscopy methods, the compound of received paraffins was investigated.
The Measurement Of Surface Areas Of Some Silicates By Solution Adsorption, Oğuz İnel, Fatma Tümsek
The Measurement Of Surface Areas Of Some Silicates By Solution Adsorption, Oğuz İnel, Fatma Tümsek
Turkish Journal of Chemistry
In this study, the adsorption from solution technique was used for the determination of surface areas of some silicate samples (bentonite, sepiolite, zeolitic tuff and kaolin). Methylene blue (MB), orthophenanthroline (OP) and p-nitrophenol (PNP) were selected as solutes. The adsorption data was found to conform with the Langmuir equation within the concentration range studied, and Langmuir constants were determined for each of the samples. The surface area values obtained were compared with those determined by nitrogen adsorption. Also the results were discussed with respect to the cation exchange capacities of the samples. The specific surface area values of the samples …
A Study On N-Hydroxyamide Ethoxycarbonylhydrazones, A. Aykut İki̇zler, Ahmet Demi̇rbaş, Rza Abbasoğlu
A Study On N-Hydroxyamide Ethoxycarbonylhydrazones, A. Aykut İki̇zler, Ahmet Demi̇rbaş, Rza Abbasoğlu
Turkish Journal of Chemistry
The structures and electronic properties of N-hydroxyamide ethoxycarbonylhydrazones were investigated by a quantum-chemical method AMl. The total energies, heats of formation, dipol moments, ionization potentials, proton affinities and energies of frontier molecular orbitals (E_{HOMO} and E_{LUMO}) were calculated and discussed. The stabilities of the tautomeric forms and of E and Z isomers for these compounds were determined. The complex forming ability of these compounds with metal cations was also studied. The geometry and electronic properties of the complexes formed by N-hydroxyacetamide ethoxycarbonylhydrazone with Ni^{2+} and Cu^{2+} were investigated using ZINDO/1 semiempirical method. Moreover, these complexes were synthesized and identified.
Fundamental Noise Studies In Flame Atomic Magneto-Optic Rotation And Atomic Absorption Spectrometry, Ahmet T. İnce, Richard D. Snook, Jhon B. Dawson
Fundamental Noise Studies In Flame Atomic Magneto-Optic Rotation And Atomic Absorption Spectrometry, Ahmet T. İnce, Richard D. Snook, Jhon B. Dawson
Turkish Journal of Chemistry
A study of inherent noise sources present in a purpose built flame atomic magneto-optic rotation (AMOR) spectrometer system was carried out with a view to identifying their sources. Two different optical configurations were employed, a crossed polariser and a 45° offset polariser configuration. The offset polariser configuration was operated in both an AMOR and atomic absorption (AA) mode for the noise measurements. Two main interference frequencies were found to occur in all the optical measurement modes. An interference flame feature frequency (15.5 Hz -39.0 Hz) which arose from an ``organ-pipe'' effect in the gas flow through the flame cooling sheets. …
Studies On The Methylation Of 5-Nitro-Benzimidazoles, Mashooda Hasan, Farzana Shaheen, Uzma Yunus
Studies On The Methylation Of 5-Nitro-Benzimidazoles, Mashooda Hasan, Farzana Shaheen, Uzma Yunus
Turkish Journal of Chemistry
Methylation of 2H, 5-nitro- (1) and 2-ethyl, 5-nitro- (2) benzimidazoles separately with methyl iodide in acetone in the presence of potassium carbonate yielded 2H, 5/6-nitro-(3A and 3B) and 2-ethyl, 5/6-nitro- (4A and 4B) methylbenzimidazoles respectively. Methylation of 1 and 2 in dimethylformamide in place of acetone yielded not only 3A, 3B and 4A, 4B respectively, but in addition 1,3-dimethyl-5-nitro-benzimidazol-2-one (5) was also obtained in each case. The structure of the synthesized compounds was determined with the help of mass and ^1H NMR spectroscopic analysis.
Determination Of Thermodynamic Parameters Of Some Complexes Of 9-Ethyl-3-Carbazolecarboxaldehyde 4-Phenyl-3-Thiosemicarbazone (Eccapt), E. Güler Akgemci̇, Tevfi̇k Atalay
Determination Of Thermodynamic Parameters Of Some Complexes Of 9-Ethyl-3-Carbazolecarboxaldehyde 4-Phenyl-3-Thiosemicarbazone (Eccapt), E. Güler Akgemci̇, Tevfi̇k Atalay
Turkish Journal of Chemistry
The complexes of Cu(II), Co(II), Zn(II), and Cd(II) with 9-ethyl-3-carbazolecarboxaldehyde 4-phenyl-3-thiosemicarbazone were synthesized and their stability constants were determined using a spectrophotometric method at different temperatures (25, 30, 35 and 40 \pm 0.1°C) and ionic strengths (0.05, 0.01 and 0.20 M KNO_3) in 50% (v/v) aqueous DMF. From these constants, the thermodynamic stability constants and thermodynamic parameters (\Delta G°, \Delta H° and \Delta S°) were calculated.
Flavonol Glycosides From Consolida Armeniaca, Mustafa Küçüki̇slamoğlu, Nuretti̇n Yayli, Hasan Basri̇ Şentürk, Hasan Genç, Seçki̇n Özden
Flavonol Glycosides From Consolida Armeniaca, Mustafa Küçüki̇slamoğlu, Nuretti̇n Yayli, Hasan Basri̇ Şentürk, Hasan Genç, Seçki̇n Özden
Turkish Journal of Chemistry
Three known flavonol glycosides, i.e., kaempferol 3,7-O-\( \alpha \)-L-dirhamnopyranoside ({\bfseries 1}), kaempferol 3-O-\( \beta \)-D-glucopyranosyl-(1\( \ra \)2)-\( \alpha$-L-rhamnopyranoside-7-O-\( \alpha \)-L-rhamnopyranoside ({\bfseries 2}) and kaempferol 3-O-\( \alpha \)-L-rhamnopyranoside-7-O-\( \beta \)-D-glucopyranosyl-(1\( \ra \)2)-\( \alpha \)-L-rhamnopyranoside ({\bfseries 3}), were isolated for the first time from the flowers of {\itshape Consolida armeniaca}, and the structures of flavonol glycosides were deduced by high field 1D and 2D NMR and FAB-MS spectroscopies. The acetyl derivatives of {\bfseries 1-3} were also prepared ({\bfseries 1a, 2a, 3a}) and identified by NMR and positive FAB mass spectra.
High Fluorescence Emissions Of Some Natural Benzofurane Derivatives Isolated From Styrax Officinalis, Siddik İçli̇, Hüseyi̇n Anil, Bi̇rcan Di̇ndar, Özgen Alankuş Çalişkan, Yurdanur Yayla, Andrey O. Doroshenko, Serap Alp
High Fluorescence Emissions Of Some Natural Benzofurane Derivatives Isolated From Styrax Officinalis, Siddik İçli̇, Hüseyi̇n Anil, Bi̇rcan Di̇ndar, Özgen Alankuş Çalişkan, Yurdanur Yayla, Andrey O. Doroshenko, Serap Alp
Turkish Journal of Chemistry
The fluorescent properties of several natural benzofuran derivatives, egonols, isolated from {\it Styrax officinalis}, were determined. The studied egonol derivatives were found to be effective UV organic luminophores, with quantum yields of near to unity, \( \varphi_{f} \) = 0.92. The fluorescence quenching experiments with electron donor molecules of aniline, N,N-dimethylaniline and carbazolocarbazole, presented very high efficiency of quenching at above diffusion quenching rates of 4.5$\times$10\( ^{10} \), 2.1$\times$10\( ^\times \) and 5.6$\times$10\( ^{12} \) s\( ^{-1} \)mol\( ^{-1} \), respectively. A strong electron acceptor molecule, tetranitrofluorenone, presented quenching rate of 2.6$\times$10\( ^{11} \) s\( ^{-1} \)mol\( ^{-1} \). It …
Kinetics And Thermodynamics Of Oil Extraction From Sun Ower Seeds In The Presence Of Aqueous Acidic, Hüseyi̇n Topallar, Ümi̇t Geçgel
Kinetics And Thermodynamics Of Oil Extraction From Sun Ower Seeds In The Presence Of Aqueous Acidic, Hüseyi̇n Topallar, Ümi̇t Geçgel
Turkish Journal of Chemistry
Oil extraction was performed in aqueous HCl, H_2SO_4 and H_3PO_4 solutions with n-hexane (C_6H_{14}) at 30, 40, 50 and 60 ^oC using 10 gr of sunflower seeds over 1 h with 10-min. sampling intervals. The optimum acid concentration was wt. 10% for each acid, and the highest oil yield was obtained in the extraction procedure with n-hexane containing H_2SO_4. The extraction process was observed with regard to the percent oil yield versus time, and the reaction order was found to be first-order kinetics by the differential method. The activation energy for the oil extraction kinetics of sunflower seeds with 10% …
The Effect Of Peripheral Circuits On The Total \Pi-Electron Energies Of Cyclacenes, Lemi̇ Türker
The Effect Of Peripheral Circuits On The Total \Pi-Electron Energies Of Cyclacenes, Lemi̇ Türker
Turkish Journal of Chemistry
Within the framework of the Hückel molecular orbital theory, certain linear models are developed to express the contribution of peripheral circuits of cyclacenes into their total \pi-electron energies, which explain why cyclacenes exhibit the cryptoannulenic behavior as their peripheral circuits which are annulenic in character.
Adsorption Of Some Heavy Metal Ions From Aqueous Solution By Activated Carbon And Comparison Of Percent Adsorption Results Of Activated Carbon With Those Of Some Other Adsorbents, İlhan Uzun, Fuat Güzel
Adsorption Of Some Heavy Metal Ions From Aqueous Solution By Activated Carbon And Comparison Of Percent Adsorption Results Of Activated Carbon With Those Of Some Other Adsorbents, İlhan Uzun, Fuat Güzel
Turkish Journal of Chemistry
In this study, removal of some heavy metals ions (Mn^{2+}, Fe^{2+}, Ni^{2+} and Cu^{2+}) from aqueous solution by adsorption was investigated. For this purpose, high-grade MnSO_4.H_2O, FeSO_4.7H_2O, NiSO_4.7H_2O and CuSO_4.5H_2O were used as heavy metal samples. The commercial activated carbon (Merck 2514), chitosan and agar were used as adsorbents. The pH of each solution was not controlled. This is because the net interaction between the adsorbent and the heavy metal could be disturbed by the buffer solution. Therefore, all experiments were carried out in a pH range from 5.3 to 5.5. The equilibrium adsorption contact times were determined for M …
Electroreduction Of Some Diazine And Triazine Pesticides At The Dropping Mercury Electrode, Petr Zuman, Marina Privman, Masami Shibata, Jiri Ludvik
Electroreduction Of Some Diazine And Triazine Pesticides At The Dropping Mercury Electrode, Petr Zuman, Marina Privman, Masami Shibata, Jiri Ludvik
Turkish Journal of Chemistry
Electroanalytical methods enable determination of electroactive species in nonhomogeneous systems, as limiting currents are little affected by the presence of solid and colloidal particles. An example of such applications of electrochemical methods are studies of binding of toxic substances, such as pesticides, on slightly soluble polymers, such as lignin. To successfully apply polarographic methods for following free pesticides in a slurry of lignin, it is first necessary in principle to elucidate the electrochemical processes involved. In aqueous buffered solutions the electron transfers, in which organic compounds participate, are in the majority of cases accompanied by chemical reactions. To elucidate the …