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Articles 1 - 30 of 212
Full-Text Articles in Physical Sciences and Mathematics
Multiply Charged Ions Produced After Deexcitation Processes For Important Elements In Astrophysics, Adel M. El-Shime, Adel A. Ghoneim, Yehia A. Lotfy
Multiply Charged Ions Produced After Deexcitation Processes For Important Elements In Astrophysics, Adel M. El-Shime, Adel A. Ghoneim, Yehia A. Lotfy
Turkish Journal of Physics
Selection random number method (Monte Carlo technique) is used to calculate the ion charge state distributions (CSD) and mean ion charge \bar{q} after K-, L_{I}, L_{III}- and M_{I}- shell ionization in neutral atoms and their q-fold ground state ions (q = 0 to 10) from C to Fe elements. Atomic data for radiative and non-radiative transitions and electron shake off process, which is used in the modeling vacancy cascade program, are computed with relativistic wave functions. Use of atomic data is important to accurately model vacancy cascades. To enhance the agreement between calculated and experimental values, the electron shake-off processes …
Modeling Of Infrared Radiation For All Skies From Easy-To-Measure Meteorological Parameters At Tropical Location: Ilorin, Nigeria, Sunday O. Udo
Modeling Of Infrared Radiation For All Skies From Easy-To-Measure Meteorological Parameters At Tropical Location: Ilorin, Nigeria, Sunday O. Udo
Turkish Journal of Physics
Downward infrared radiation (L) and some easy-to-measure meteorological variables (relative humidity, clearness index and vapour pressure) were collected for a period of two years at Ilorin. Downward infrared radiation data were obtained using a pyrgeometer (Eppley-PIR), while data for relative humidity and vapour pressure for Ilorin were obtained from the Nigerian Meteorological Services, Lagos. Based on these data, using statistical regression analysis, empirical models (seven one-variable and nine two-variable) for predicting daily mean infrared radiation, from both clear and cloudy skies, were tested. Their advantage is that they only make use of easily measured meteorological parameters. The best one-variable model …
Operation Parameters Of The Thermionic Vacuum Arc Discharge, Tamer Akan
Operation Parameters Of The Thermionic Vacuum Arc Discharge, Tamer Akan
Turkish Journal of Physics
The thermionic vacuum arc (TVA) discharge with evaporating anodes employing directly heated thermionic cathodes is investigated. The TVA discharge generates a pure, gas-free metal vapor plasma containing ions with a directed energy. The TVA is strongly controlled by the cathodic electron beam and there is a quite good stability of important operation parameters like the arc voltage and the arc current.
Development Of Double Discharge Pulsed Electron Beam Generator And Its Preliminary Applications In Material Processing, Hi̇lal Göktaş, Gulay Oke, Mircea Udrea
Development Of Double Discharge Pulsed Electron Beam Generator And Its Preliminary Applications In Material Processing, Hi̇lal Göktaş, Gulay Oke, Mircea Udrea
Turkish Journal of Physics
This article presents the construction of a fast, intense electron beam generator, several of its operational properties and its preliminary applications. A fast filamentary discharge produced in a tube filled with Argon gas at pressure of about 0.1 torr. An electron beam is obtained with a current intensity of about 0.6 A for a 25 ns duration. The length of the filamentary discharge and the behavior of the beam in the magnetic field are examined. The interaction of the beam with different targets was investigated by Scanning Electron Microscope. It is also demonstrated that the device can be used to …
The Influence Of Ge Content And Annealing Temperature On The D.C And A.C Conductivity Of Ge_{X}Se_{1 - X} Thin Films, Maysoon Faisal Alias, M. N. Makadsi, Z. M. Al-Ajeli
The Influence Of Ge Content And Annealing Temperature On The D.C And A.C Conductivity Of Ge_{X}Se_{1 - X} Thin Films, Maysoon Faisal Alias, M. N. Makadsi, Z. M. Al-Ajeli
Turkish Journal of Physics
Various samples of Ge_{x}Se_{1 - x} system have been prepared for x = 0.05, 0.15& 0.25 in an evacuated quartz tube. Thin films of Ge_{x}Se_{1 - x} film have been prepared via a thermal evaporation method with 350 \pm 5 nm thickness and rate deposition 6 nm/s. The alloy structure and thin films have been examined by X-ray diffraction (XRD). Atomic absorption spectroscopy (AAS) was used to examine the concentration of the composite elements (Ge and Se). The d.c and a.c conductivity of Ge_{x}Se_{1 - x} thin film have been studied as a function of Ge content x and annealing …
Microwave Signal Attenuation In Harmattan Weather Along Calabar-Akampkpa Line-Of-Sight Link, O. E. Eyo, A. I. Menkiti, Sunday O. Udo
Microwave Signal Attenuation In Harmattan Weather Along Calabar-Akampkpa Line-Of-Sight Link, O. E. Eyo, A. I. Menkiti, Sunday O. Udo
Turkish Journal of Physics
Line-of-sight (LOS) attenuation at 6.44GHz was measured at Calabar (4° 58' N, 8° 17' E) for ten months (Aug '93-May '94) using the Nigerian Telecommunications radio signal. The measurement was made with the intent of highlighting microwave signal attenuation in Harmattan weather conditions. The results are presented in terms of mean signal level and fog attenuation, fade rate distribution, fade depth distribution and scintillation index. The observed attenuation values due to Harmattan (fog) and the calculated (using Altshuler's model) are in fairly good agreement. Also, the statistics of fade distribution show fast fading of longer duration of the order of …
Relationship Between Global Solar Radiation And Sunshine Duration For Onne, Nigeria, Louis E. Akpabio, Sunday E. Etuk
Relationship Between Global Solar Radiation And Sunshine Duration For Onne, Nigeria, Louis E. Akpabio, Sunday E. Etuk
Turkish Journal of Physics
Measurements of global solar radiation and sunshine duration data during the period from 1984 to 1999 at Onne (within the rainforest climatic zone of southern Nigeria) were used to establish an Angstrom-type correlation equation. Five other commonly used correlations between global solar radiation and sunshine duration were also used to estimate global solar irradiation for Onne and their results are compared with our model. A good agreement (greater than 90% in most cases) was observed between the measured and the predicted values of our model.
Initial Electron Beam Polarization Measurement In E-\Gamma Collisions, Gökhan Ünel
Initial Electron Beam Polarization Measurement In E-\Gamma Collisions, Gökhan Ünel
Turkish Journal of Physics
The future high energy e e colliders, together with the complementary \gamma \gamma option, will offer possibilities for both discovery and precision physics. The uncertainty on the initial beam polarizations contributes to the systematic errors in each case. Therefore, it is crucial to obtain the precise beam polarizations by independent measurements. The e \gamma \rightarrow \nu W process in the e \gamma mode can be used to experimentally determine the polarization of the initial e beam. This note addresses the feasibility of making such a measurement with a relative statistical error of one percent. Generator and detector level MC tools …
Nuclear Matrix Elements Of Double Beta Decay In Deformed Nuclei, C. Selam, Atalay Küçükbursa, H. Bi̇rcan, H. A. Aygör, T. Babacan, İ. Maraş, A. Kökçe
Nuclear Matrix Elements Of Double Beta Decay In Deformed Nuclei, C. Selam, Atalay Küçükbursa, H. Bi̇rcan, H. A. Aygör, T. Babacan, İ. Maraş, A. Kökçe
Turkish Journal of Physics
Nuclear matrix elements (M_{GT}) for two-neutrino double beta transitions of selected nuclei were calculated via a QRPA approach by considering the charge-exchange spin-spin interactions in the particle-hole channel among nucleons. Calculations were performed for both spherical and deformed cases of nuclei. As a result of these calculations, it has been seen that, although the value of the nuclear matrix elements in deformation case are 2-4 times smaller when compared with that of the spherical case, it is still 2-8 times greater than the experimental values.
High-Pressure Phase Transition In Some Alkali Halides Using Interatomic Potential Model, Harun Reşi̇t Yazar
High-Pressure Phase Transition In Some Alkali Halides Using Interatomic Potential Model, Harun Reşi̇t Yazar
Turkish Journal of Physics
We have predicted the phase transition pressure in some alkali halides NaCl and KCl using an interatomic potential approach based on a rigid ion model. We have obtained phase transition pressures 28.69 and 2.4 GPa, respectively, and are in close agreement with their corresponding experimental transition pressures 29.0 and 2.0 GPa. This approach is promising with respect to the prediction of the phase transition pressures of other alkali halides.
Study Of The Structure And Some Physical Properties Of Sodium-Boro-Phosphate Glasses Containing Antimony And Iron Oxides, Karam Abdel-Aati̇ Ali, Ahmet Gamal El-Din Mostafa
Study Of The Structure And Some Physical Properties Of Sodium-Boro-Phosphate Glasses Containing Antimony And Iron Oxides, Karam Abdel-Aati̇ Ali, Ahmet Gamal El-Din Mostafa
Turkish Journal of Physics
Boro-phosphate glasses containing transition metal oxides are of special interest. Hence, some sodium-Boro-phosphate glasses containing iron and antimony oxides were prepared and investigated. The structural investigation indicated the presence of different borate groups as well as tetragonal phosphate units. Most of the iron cations were found to occupy the low spin Fe^{3 +} in the tetrahedral coordination state. It was observed that some antimony act as network former cations and some others act as bridges between any two adjacent polyhedra. At high antimony oxide content, the formation of some Sb-Fe bonds was also detected. The magnetic susceptibility measurements showed a …
Studies On Some Lithium-Borate Glasses Containing Iron And Copper, G. A. Yahya
Studies On Some Lithium-Borate Glasses Containing Iron And Copper, G. A. Yahya
Turkish Journal of Physics
A lithium-borate-glass system containing iron and copper cations has been thoroughly investigated, in order to obtain information about the structural role of both the iron and copper in such glass hosts. The amorphous phase of the prepared glass samples was confirmed from their X-ray diffraction. From the infrared spectra it was concluded that the glass networks are highly deformed and boron appeared in both tri- and tetra-hedral coordination states as well as in some ring structure. As copper was introduced, replacing lithium, it acts as a network modifier only while the iron acts as network former (FeO_4). The molar magnetic …
Change Of Birefringence In Dye-Doped Nematic Liquid Crystals Under Laser Illumination, S. Eren San, Oğuz Köysal, Serhat Özder, F. Necati̇ Ecevi̇t
Change Of Birefringence In Dye-Doped Nematic Liquid Crystals Under Laser Illumination, S. Eren San, Oğuz Köysal, Serhat Özder, F. Necati̇ Ecevi̇t
Turkish Journal of Physics
Birefringence property of E7 nematic liquid crystal is investigated via voltage dependent transmittance spectrums. Measurements are performed at wavelength 632.8 nm, which is the absorbance peak of our sample including anthraquinone derivative Disperse Blue 14. Results of dye-doped samples are compared with those undoped for dark and laser illuminated cases. It was observed that birefringence is dependent on laser illumination for dye-doped samples, up to a threshold voltage after which it is constant.
Decoherence In Two Coupled Qubits, Kristian Rabenstein, Dmitri V. Averin
Decoherence In Two Coupled Qubits, Kristian Rabenstein, Dmitri V. Averin
Turkish Journal of Physics
We have developed quantitative description of quantum coherent oscillations in the system of two coupled qubits in the presence of weak decoherence that in general can be correlated between the two qubits. It is shown that in the experimentally realized scheme of excitation of the oscillations, their waveform is not very sensitive to the magnitude of decoherence correlations. Modification of this scheme into potentially useful probe of the degree of decoherence correlations at the two qubits is suggested.
Quantum State Generation And Entanglement Manipulation Using Linear Optics, Şahi̇n Kaya Özdemi̇r, Takashi Yamamoto, Masato Koashi, Nobuyuki Imoto
Quantum State Generation And Entanglement Manipulation Using Linear Optics, Şahi̇n Kaya Özdemi̇r, Takashi Yamamoto, Masato Koashi, Nobuyuki Imoto
Turkish Journal of Physics
Quantum information processing (QIP) requires unitary operations, measurements and synthesis, manipulation and characterization of arbitrary quantum states. Linear optics provides efficient tools for these purposes. In this review paper, we introduce the elements of linear optics toolbox, and briefly discuss some experimental and theoretical investigations using this toolbox. Our main focus will be the qubit state generation and entanglement extraction using linear optics toolbox.
Studies On The Opto-Electronic Constants Of Alkali-Halide Crystals, Mahmoud A. Salem
Studies On The Opto-Electronic Constants Of Alkali-Halide Crystals, Mahmoud A. Salem
Turkish Journal of Physics
In this presentation, the correlation between refractive index n of alkali-halide crystals and both energy band gap E_{g} and Pauling's electronegativity difference \Delta x have been studied. The following relations are proposed for estimating the refractive index n: n^2 + C = A / E_{g} ^{1 / 2} and n^2 + C = E / (\Delta x)^{0.425}, where A, C and E are numerical constants. In addition, an interrelation between the energy band gap E_{g} and electronegativity difference \Delta x has been also proposed. The proposed relation is E_g = 4.45 (\Delta x)^{0.85}. The estimated values of the refractive index …
Extensional Neotectonic Regime Through The Ne Edge Of The Outer Isparta Angle, Sw Turkey: New Field And Seismic Data, Ali̇ Koçyi̇ği̇t, A. Arda Özacar
Extensional Neotectonic Regime Through The Ne Edge Of The Outer Isparta Angle, Sw Turkey: New Field And Seismic Data, Ali̇ Koçyi̇ği̇t, A. Arda Özacar
Turkish Journal of Earth Sciences
The Akşehir-Afyon Graben (AAG) is a 4-20-km-wide, 130-km-long NW-trending depression that separates central Anatolia in the NE and the Isparta Angle (IA) in the SW. Its southwestern margin-bounding fault determines the northeast edge of the outer IA that was previously interpreted as a compressional neotectonic structure, whereas our field evidence and recent seismic data substantiated that it is an oblique-slip normal fault characterising an extensional neotectonic regime. The AAG has an episodic and asymmetrical evolutionary history. This is indicated by two superimposed graben infills and structures. The older infill is folded, thrust-faulted and Early-early Middle Miocene in age. The younger …
Coulomb Stress Interactions And The 1999 Marmara Earthquakes, Zi̇yadi̇n Çakir, A. Aykut Barka, Emre Evren
Coulomb Stress Interactions And The 1999 Marmara Earthquakes, Zi̇yadi̇n Çakir, A. Aykut Barka, Emre Evren
Turkish Journal of Earth Sciences
The effects of previous earthquakes on the 1999 İzmit and Düzce earthquakes, the influence of the İzmit earthquake on the Düzce earthquake, and the seismic hazard in the Marmara region are investigated using Coulomb failure stress. Calculation of the Coulomb stress changes using the fault parameters deduced from the modelling of the coseismic Synthetic Aperture Radar Interferometry (InSAR) and GPS data shows that the İzmit earthquake occurred where the Coulomb stress was increased by the previous events. Despite the stress decrease on the Düzce Fault due to the events before 1999, the Düzce earthquake appears to have been triggered by …
Kinematics Of The November 12, 1999 (Mw=7.2) Düzce Earthquake Deduced From Sar Interferometry, Zi̇yadi̇n Çakir, A. Aykut Barka, Jean Bernard De Chabalier, Rolando Armijo, Bertrand Meyer
Kinematics Of The November 12, 1999 (Mw=7.2) Düzce Earthquake Deduced From Sar Interferometry, Zi̇yadi̇n Çakir, A. Aykut Barka, Jean Bernard De Chabalier, Rolando Armijo, Bertrand Meyer
Turkish Journal of Earth Sciences
On November 12 1999, a destructive earthquake struck the Düzce area, following the 17 August 1999 İzmit earthquake that had occurred to the west about 3 months earlier. The Mw=7.2 Düzce earthquake was somewhat interesting in several ways. The most surprising feature of this earthquake is related to its rupture geometry, which appears to contradict what is commonly observed in strike-slip earthquakes. First, compared to its magnitude, the length of the surface rupture mapped in the field was rather short (~35 km). Second, according to seismic and some geodetic observations, the fault plane dips to the north at a very …
Timing Of Late Holocene Earthquakes On The Eastern Düzce Fault And Implications For Slip Transfer Between The Southern And Northern Strands Of The North Anatolian Fault System, Bolu, Turkey, Christopher Hitchcock, Erhan Altunel, A. Aykut Barka, Jeffrey Bachhuber, William Lettis, John Helms, Scott Lindvall
Timing Of Late Holocene Earthquakes On The Eastern Düzce Fault And Implications For Slip Transfer Between The Southern And Northern Strands Of The North Anatolian Fault System, Bolu, Turkey, Christopher Hitchcock, Erhan Altunel, A. Aykut Barka, Jeffrey Bachhuber, William Lettis, John Helms, Scott Lindvall
Turkish Journal of Earth Sciences
Results of trenching across the eastern Düzce Fault document that surface rupture has occurred repeatedly on the fault prior to the 1999 Düzce earthquake, and that offset during previous earthquakes occurred at the same location and with similar amounts and type of slip as that of the 1999 earthquake. The most recent pre-1999 earthquake on the fault occurred about 300 years ago. At least four and possibly five earthquakes (including 1999) have occurred in the past 2100 years. The earthquake recurrence interval ranges from 300 to 800 years. Estimates of cumulative slip on the northern and southern branches of the …
Earthquake Faulting At Ancient Cnidus, Sw Turkey, Erhan Altunel, Iain S. Stenwart, Luigi Piccardi, A. Aykut Barka
Earthquake Faulting At Ancient Cnidus, Sw Turkey, Erhan Altunel, Iain S. Stenwart, Luigi Piccardi, A. Aykut Barka
Turkish Journal of Earth Sciences
The ruins of Cnidus, an important ancient city in southwestern Asia Minor, lie directly on an earthquake fault - the Cnidus Fault. Offset and deformed archaeological remains along the trace of the fault testify to its recent activation. The ancient city's famous Round Temple of Aphrodite is vertically offset by 0.35 m across the fault. The fault also forms the back wall to the Sanctuary of Demeter where Roman-age walls are displaced and deformed by slip on the fault. Archaeological evidence suggests multiple episodes of abrupt destruction at the site and, in the Sanctuary of Demeter, indicates past earthquake surface …
Earthquakes And Seismic Faulting: Effects On Tunnels, Villy A. Kontogianni, Stathis C. Stiros
Earthquakes And Seismic Faulting: Effects On Tunnels, Villy A. Kontogianni, Stathis C. Stiros
Turkish Journal of Earth Sciences
A study of tunnels in areas affected by strong earthquakes in the last 50-100 years revealed at least three cases of tunnels damaged by earthquake shaking or offset by seismic faulting, including the Bolu (Turkey) twin tunnels, which collapsed during the 1999 Düzce earthquake. These data indicate that tunnels cannot be considered as structures invulnerable to earthquakes. Furthermore, the tectonic offset of tunnels shows that certain observed seismic surface ruptures are not necessarily indicative of tectonic faulting and represent only secondary local ground instability effects.
Roveacrinids From Northern Arabian Plate In Se Turkey, Anna Farinacci, Riccardo Manni
Roveacrinids From Northern Arabian Plate In Se Turkey, Anna Farinacci, Riccardo Manni
Turkish Journal of Earth Sciences
Crinoid remains from Cenomanian limestones in SE Anatolia have been studied. These crinoids belong to the family Roveacrinidae and are characterised by their lacking a stem and free living above the sea floor. A new species, Roveacrinus derdereensis Manni, n. sp., has been erected.
Polyethyleneimine-Coated Capillaries For The Separation Of Dna By Capillary Electrophoresis, M. Sai̇d Nutku, F. Bedi̇a Eri̇m Berker
Polyethyleneimine-Coated Capillaries For The Separation Of Dna By Capillary Electrophoresis, M. Sai̇d Nutku, F. Bedi̇a Eri̇m Berker
Turkish Journal of Chemistry
A new capillary electrophoresis of DNA fragments has been achieved with the cooperative effects of the electrophoretic and electroosmotic mobilities realized via the polyethyleneimine (PEI) coating of the capillary walls. As a result, seven of the 11 different-sized DNA fragments have produced resolved CE peaks. Our results demonstrate that analyses of DNA constituents can be performed under a wide range of conditions by the appropriate tuning of the coating and filler within the capillary.
Search For A Nonelectrocyclic Cyclization Of Nitrosostyrene: Rearrangements Of Michael Adducts From Dmad And \Alpha-Dialkylamino Oximes, Necdet Coşkun, Nevi̇n Arikan
Search For A Nonelectrocyclic Cyclization Of Nitrosostyrene: Rearrangements Of Michael Adducts From Dmad And \Alpha-Dialkylamino Oximes, Necdet Coşkun, Nevi̇n Arikan
Turkish Journal of Chemistry
The aza-Claisen rearrangement product of the Michael adducts 2 from \alpha-dialkylaminoacetophenone oximes and DMAD underwent fragmentation to give dialkylaminomaleate, and benzonitrile at reflux in acetonitrile. The fragmentation was assumed to proceed through an unstable 4H-1,2-oxazete 6. The same reaction performed at room temperature, in addition to the nitrile and maleate, gave the corresponding 2-(2-dialkylamino-1-phenylethylideneaminooxy)-but-2- enedioic acid dimethyl esters 8 and 9. Compounds 9 isomerized to 8 on heating in acetonitrile.
Synthesis Of Some New Benzimidazole Carbamate Derivatives For Evaluation Of Antifungal Activity, Canan Kuş, Nurten Altanlar
Synthesis Of Some New Benzimidazole Carbamate Derivatives For Evaluation Of Antifungal Activity, Canan Kuş, Nurten Altanlar
Turkish Journal of Chemistry
The synthesis and structure elucidation of methyl 5(6)-fluoro-6(5)-substituted-1H-benzimidazole carbamate derivatives are performed and their antifungal activities evaluated against Candida albicans.
Changes In Chlorophyll-Carotenoid Contents, Antioxidant Enzyme Activities And Lipid Peroxidation Levels In Zn-Stressed Mentha Pulegium, Ni̇lgün Candan, Leman Tarhan
Changes In Chlorophyll-Carotenoid Contents, Antioxidant Enzyme Activities And Lipid Peroxidation Levels In Zn-Stressed Mentha Pulegium, Ni̇lgün Candan, Leman Tarhan
Turkish Journal of Chemistry
The relationships between chlorophyll-carotenoid contents, the antioxidant enzyme activities, such as superoxide dismutase (SOD), catalase (CAT), ascorbate-dependent peroxidase (AsA-dep POD) and guaiacol-dependent peroxidase (Gua-dep POD), and lipid peroxidation (LPO) levels were investigated in leaves at different positions of M. pulegium grown in nutrient medium containing 0-1 \mu M Zn. The maximum chlorophyll-carotenoid content's SOD and CAT activities and the minimum LPO level were observed in leaf 6 at 7.6 10^{-2} \mu M Zn (as control). While chlorophyll-carotenoid contents in the absence of Zn were lower than those of the control, SOD and CAT activities significantly increased with decreasing Zn concentration. …
Determination Of H_{2}O_{2} Content Of Various Water Samples Using A Chemiluminescence Technique, Tuğba Tüğsüz, Elmas Gök, Serdar Ateş
Determination Of H_{2}O_{2} Content Of Various Water Samples Using A Chemiluminescence Technique, Tuğba Tüğsüz, Elmas Gök, Serdar Ateş
Turkish Journal of Chemistry
Hydrogen peroxide (H_{2}O_{2}) plays an important role in natural water samples. In this study H_{2}O_{2} concentrations were quantified in different water samples by chemiluminescence detection. This method was chosen because of its high sensitivity and suitability for determining low concentrations of H_{2}O_{2}. H_{2}O_{2} is introduced to the oxidation reaction of alkaline luminol solutions in the presence of Co^{2 + } ion catalyst. When these components are mixed, blue light (\lambda = 440 nm) is emitted. Maximum chemiluminescence intensity occurs within 2 s after mixing and is continuous for up to a few minutes, permitting accurate measurements at selected delay times. …
Chromatographic Determination Of Phenolic Acids In The Snowdrop By Hplc, Mustafa Tüzen, Mustafa Özdemi̇r
Chromatographic Determination Of Phenolic Acids In The Snowdrop By Hplc, Mustafa Tüzen, Mustafa Özdemi̇r
Turkish Journal of Chemistry
Free and esterified phenolic acids of Galanthus elwesii (snowdrop) were extracted with petroleum ether and determined by HPLC. Cinnamic, ferulic, vanillic, p-coumaric, p-hydroxy benzoic, and caffeic acids were detected by a linear gradient elution with acetic acid/water (2:98 v/v) and acetic acid/acetonitrile/water (2:30:68 v/v) as the mobile phases in 30 min with a flow rate of 1.5 mL/min. Among the acids from snowdrop extracts, p-hydroxy benzoic was the major constituent followed by vanillic and ferulic acids.
Differential Pulse Polarographic Determination Of Enalapril Maleate, Fi̇kri̇ye Elmali, Güzi̇n Alpdoğan, Şule Aycan, Sidika Sungur
Differential Pulse Polarographic Determination Of Enalapril Maleate, Fi̇kri̇ye Elmali, Güzi̇n Alpdoğan, Şule Aycan, Sidika Sungur
Turkish Journal of Chemistry
A differential pulse polarographic (DPP) method has been developed for the quantitative analysis of enalapril maleate. Enalapril maleate gives a peak at -1.4 V in methanol. A calibration curve was constructed for the 20 -100 \mu g ml^{-1} concentration range. As a reference method, a reversed phase high performance liquid chromatographic procedure has been developed. Commercially available tablets were analysed by the two methods. Statistical evaluations indicated that there was no significant difference between the mean values and precisions of the two methods at a 95\% confidence level.