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Study Of Pseudorapidity Distributions Of Shower Particles Emitted In Interactions Of Nuclei With Emulsion At 4.1- 4.5 A Gev/C, Sakina Fakhraddin
Study Of Pseudorapidity Distributions Of Shower Particles Emitted In Interactions Of Nuclei With Emulsion At 4.1- 4.5 A Gev/C, Sakina Fakhraddin
Turkish Journal of Physics
The pseudorapidity distributions of shower particles in interactions of 4.5 A GeV/c ^{12}C, ^{16}O, ^{28}Si and ^{22}Ne at 4.1 A GeV/c with emulsion have been presented. The dependence of these distributions on the target nuclei (AgBr and CNO) have been investigated. The energy density for ^{24}Mg--Pb interactions is calculated using the Bjorken model.
Microstructure Characterization Of Znfe_{2-X}M_{X}O_{4} (M = Bi, Y And X = 0.1, 0.2) Ferrites By The Rietveld Refinement, Mansour Al-Haj
Microstructure Characterization Of Znfe_{2-X}M_{X}O_{4} (M = Bi, Y And X = 0.1, 0.2) Ferrites By The Rietveld Refinement, Mansour Al-Haj
Turkish Journal of Physics
The microstructure of the ferrites was analyzed by the Reitveld refinement method. The Bi-containing ferrites revealed a decrease in the lattice parameter as the Bi^{3+} concentration is increased, due to the distortion of the ferrite lattice. There was a minor distortion in the ZnFe_{1.9}Y_{0.1}O_4 ferrite lattice. A minor yttrium oxide phase coexisted with the ZnFe_{1.8}Y_{0.2}O_4 spinel phase.
Composition Dependence Of Photoconductivity In Amorphous Thin Films Of Se_{.80-X}Te_{.20}Ge_X, Deepak Kumar, Santosh Kumar
Composition Dependence Of Photoconductivity In Amorphous Thin Films Of Se_{.80-X}Te_{.20}Ge_X, Deepak Kumar, Santosh Kumar
Turkish Journal of Physics
The present paper reports the dependence on composition of photoconductivity in vacuum evaporated thin films of amorphous Se_{.80-x}Te_{.20}Ge_x (x = .05, .10, .15 and .20). Temperature dependence of conductivity in dark as well as in presence of light show that conduction is through a thermally activated process in both cases. The activation energy is found to decrease with increase in light intensity, indicating shift of the Fermi level with intensity. A correlation between activation energy and the pre-exponential factor is observed in all the compositions, which could be fitted to the Meyer-Neldel rule. Measurements on the dependence of photoconductivity on …
Low Frequency Dispersion In Non-Conducting Contacts In Humidity, Altaf Husain, S. Shakeel Ahmed
Low Frequency Dispersion In Non-Conducting Contacts In Humidity, Altaf Husain, S. Shakeel Ahmed
Turkish Journal of Physics
To develop an enhanced understanding of an aspect of the charge transport mechanism in systems composed of solid-solid insulating contacts, the dynamic dielectric response of sand grains and of silica-silica rod contacts was investigated at dry and at 97% relative humidity (RH), in the frequency range 10^{-2} to10^5 Hz. In dry atmosphere no appreciable amount of conductivity is observed, while in humidity the response follows a strongly dispersive behaviour. Sharp rise in capacitance gives a clear evidence for the storage of charge in the transport process. Collectively, the conductance of the sand grains increases super-linearly with the number of contacts …
Optical Characterization Of Chemical Bath Deposited Bismuth Oxyiodide (Bioi) Thin Films, F. I. Ezema
Optical Characterization Of Chemical Bath Deposited Bismuth Oxyiodide (Bioi) Thin Films, F. I. Ezema
Turkish Journal of Physics
Thin films of Bismuth oxyiodide (BiOI) were deposited, using chemical bath deposition techniques. The films were characterized using energy dispersive x-ray fluorescence (EDXRF) and Fourier transform infrared (FTIR) spectroscopy for chemical composition, and a spectrophotometer for the analysis of spectral absorbance / transmittance / reflectance. Deposited film thickness ranged between 0.115 and 0.140 \mu m. The optical properties deduced from the spectral absorbance / transmittance / reflectance include the maximum values of the refractive index n that ranged between 2.62 and 2.64, the extinction coefficient k ranged between 25.84 \times 10^{-3} and 42.92 \times 10^{-3} while the Optical conductivity \sigma …
Electrical And Structural Properties Of Ex-Situ Annealed Superconducting Bi_2sr_2cacu_2o_8 Thin Films Obtained By Coevaporation Of Components, Necdet Baştürk
Electrical And Structural Properties Of Ex-Situ Annealed Superconducting Bi_2sr_2cacu_2o_8 Thin Films Obtained By Coevaporation Of Components, Necdet Baştürk
Turkish Journal of Physics
Bi_2Sr_2CaCu_2O_8 system superconducting thin films were obtained by synchronized deposition of Bi, Cu, CaF_2 and SrF_2 components onto cleaved MgO (100) single crystal substrates after annealing in the temperature range 600--840 °C. The films were annealed in H_2O and O_2, then dry O_2 atmosphere for the removal of fluorine from the structure and to attain superconducting properties. X-ray powder diffraction patterns were used to characterize the obtained film structure. The films were observed to grow along c-axis perpendicular to the substrate surface with the identified reflection on the (00l, l = 6, 8, 10...) planes. The films having the critical …
Dielectric Relaxation In Glassy Se_{100 - X} Sb_X, N. Choudhary, A. Kumar
Dielectric Relaxation In Glassy Se_{100 - X} Sb_X, N. Choudhary, A. Kumar
Turkish Journal of Physics
Frequency and temperature dependence of dielectric constant \varepsilon' and dielectric loss \varepsilon'' are studied in glassy Se_{1-x} Sb_x (x = 0, 0.02, 0.04, 0.06, 0.08 and 0.10) in the frequency range from 1--10 kHz and in the temperature range 290 K to 360 K. The experimental results indicate that no dielectric dispersion exist in glassy Se in the operating range of frequencies. However, when Sb concentration increases in Se_{1-x} Sb_x (x = 0.02, 0.04, 0.06, 0.08 and 0.10) dielectric dispersion starts in the upper frequency and temperature range. The values of \varepsilon' and \varepsilon'', as functions of temperature and frequency, …
Electron-Deuteron Tensor Polarization And D-State Probability, A. K. A. Azzam, M. A. Fawzy, E. M. Hassan, A. M. Yasser
Electron-Deuteron Tensor Polarization And D-State Probability, A. K. A. Azzam, M. A. Fawzy, E. M. Hassan, A. M. Yasser
Turkish Journal of Physics
Electron-deuteron tensor polarization T_{21}(q) is calculated for thirty-three N-N local potential models. New relations have been found between the peak value of T_{21}(q) and some of the deuteron properties. An experimental value of deuteron D-state probability P_D = 5.9861\% \pm 0.2687\% is deduced.
Multiple Scale And Hamilton-Jacobi Analysis Of Extended Mathieu Equation, Özlem Yeşi̇ltaş, Mehmet Şi̇mşek
Multiple Scale And Hamilton-Jacobi Analysis Of Extended Mathieu Equation, Özlem Yeşi̇ltaş, Mehmet Şi̇mşek
Turkish Journal of Physics
In this study, we use perturbation approximations and semiclassical methods to investigate the boundary solutions of non-linear vibrating systems. The extended Mathieu Equation, related to the perturbed Van der Pol oscillator with periodic coefficients, is solved using multiple time scales. Then, using the Von Zeipel Method, which is based on the Hamilton-Jacobi theory, stability conditions are presented. It is shown that the stability boundaries are the same with those obtained by both methods.
Quantization Of Reparametrized Systems Using The Wkb Method, Khaled I. Nawafleh, Eqab M. Rabei, Humam B. Ghassib
Quantization Of Reparametrized Systems Using The Wkb Method, Khaled I. Nawafleh, Eqab M. Rabei, Humam B. Ghassib
Turkish Journal of Physics
The quantization of reparametrized systems is discussed using the WKB approximation. The Hamilton-Jacobi function, the equations of motion and the wave function---which the conditions constrain in the semiclassical limit---are determined. The success of this approach is then demonstrated for two applications. The first is an illustrative example of nonrelativistic dynamics. The second is the well-known motion of a relativistic particle in an external electromagnetic field.
Mössbauer, Infrared And X-Ray Studies For Ni_{0.5}Zn_{0.5}Cr_Xfe_{2-X}O_4 Ferrites, Mohamed Amer, S. Ata-Allah, T. Meaz, S. Aboul-Enein, M. Abd-El-Hamid
Mössbauer, Infrared And X-Ray Studies For Ni_{0.5}Zn_{0.5}Cr_Xfe_{2-X}O_4 Ferrites, Mohamed Amer, S. Ata-Allah, T. Meaz, S. Aboul-Enein, M. Abd-El-Hamid
Turkish Journal of Physics
Spinel ferrites of the system Ni_{0.5}Zn_{0.5}Cr_xFe_{2-x}O_4, 0 \le x \le 1, have been studied via Mössbauer, IR and X-ray spectra. Mössbauer spectra of the samples showed broad six-line patterns and a central paramagnetic phase. The spectra have been analyzed to two magnetic patterns, A and B, and two quadrupole doublets, C_A and C_B. The patterns A and C_A are assigned to Fe^{3+} ions at the tetrahedral A-sites and the patterns B and C_B to Fe^{3+} and Fe^{2+} ions at the octahedral B-sites. The deduced hyperfine interaction parameters; the isomer shifts, quadrupole splitting, outermost line widths, hyperfine magnetic fields and bulk …
Influence Of Solar Activity On Low Amplitude Cosmic Ray Diurnal Anisotropy, Rajesh K. Mishra, Rekha Agarwal Mishra
Influence Of Solar Activity On Low Amplitude Cosmic Ray Diurnal Anisotropy, Rajesh K. Mishra, Rekha Agarwal Mishra
Turkish Journal of Physics
A detailed study has been conducted on the occurrence of a large number of low amplitude events (LAE) of cosmic ray (CR) diurnal anisotropy during 1981--1994 as a function of solar activity. The low amplitude days with the time of maximum in the corotational/azimuthal direction do not indicate any significant correlation with solar activity. Our observations suggest that the direction of the anisotropy of LAE events contribute significantly to the long-term behaviour of the CR diurnal anisotropy. The occurrence of LAE is dominant during solar activity minimum years.
East-West And Radial Anisotropy In Cosmic Ray Modulation, Rekha Agarwal Mishra, Rajesh K. Mishra
East-West And Radial Anisotropy In Cosmic Ray Modulation, Rekha Agarwal Mishra, Rajesh K. Mishra
Turkish Journal of Physics
The cosmic ray (CR) data observed with the Deep River neutron monitoring station has been harmonically analyzed for the period 1964--95 to obtain the diurnal and semi-diurnal components of cosmic ray intensity on geomagnetically 60 quiet days. The annual diurnal anisotropy vectors have been resolved into two components: one along the 12-Hr direction, the radial anisotropy component; and the other along 18-Hr direction, east-west anisotropy component. It is observed that when the polarity of solar poloidal magnetic field (SPMF) in northern hemisphere (NH) is positive, the radial anisotropy component increases; whereas, the east-west anisotropy component decreases. This results in shifting …
Calorimetric Studies On Se_{0.68}Ge_{0.22}M_{0.10} (M = Cd, In, Pb) Chalcogenide Glasses, N. Mehta, P. Agarwal, A. Kumar
Calorimetric Studies On Se_{0.68}Ge_{0.22}M_{0.10} (M = Cd, In, Pb) Chalcogenide Glasses, N. Mehta, P. Agarwal, A. Kumar
Turkish Journal of Physics
Differential scanning calorimetry (DSC) is performed at different heating rates under non-isothermal conditions to calculate the activation energy of crystallization E_c for chalcogenide glasses Se_{0.68}Ge_{0.22}M_{0.10} (M = Cd, In and Pb) using the well known Kissinger's relation, Matusita-Sakka theory and the method of Augis-Bennett. The overall mean bond energy of these glassy alloys has been evaluated using theory of Tichy and Ticha. A good correlation has been found between E_c and . This indicates that the overall mean bond energy plays an important role in the thermal crystallization of chalcogenide glasses.
The Magnetic Behaviour Of The Surface And Bulk Components Of Tb(0001)Films, Orhan Zeybek
The Magnetic Behaviour Of The Surface And Bulk Components Of Tb(0001)Films, Orhan Zeybek
Turkish Journal of Physics
The use of circularly polarised light in photoemission from ferromagnetically ordered rare earth's (RE) shows large magnetic circular dichroism in angular dependence (MCDAD) effect. Therefore MCDAD in photoemission from RE's provides new perspectives for surface magnetism studies within the view of the recently postulated sum rules. This allows to probe magnitude and orientation of the sample magnetisation without time-consuming electron-spin analysis. The well-resolved multiplet structures have been obtained in 5p photoemission of Tb using circularly polarised light. This multiplet structure is caused by the interaction between the core level photohole and those partially filled subshell, i.e. as result of the …
Forward-Backward Diffusion With Continuous Spectrum, Jorge Aarao
Forward-Backward Diffusion With Continuous Spectrum, Jorge Aarao
Turkish Journal of Mathematics
We prove existence and uniqueness of solutions for a class of forward-backward diffusion equations via a representative example, where the second-order part has continuous spectrum, and the initial and boundary data are suitably chosen.
Corrigendum Uniqueness Of Primary Decompositions [Turkish J. Math. 27 (2003), 425--434], Patrick F. Smith
Corrigendum Uniqueness Of Primary Decompositions [Turkish J. Math. 27 (2003), 425--434], Patrick F. Smith
Turkish Journal of Mathematics
No abstract provided.
Trilobites From The Çal Tepe Formation (Cambrian), Near Seydişehir, Central Taurides, Southwestern Turkey, William T. Dean
Trilobites From The Çal Tepe Formation (Cambrian), Near Seydişehir, Central Taurides, Southwestern Turkey, William T. Dean
Turkish Journal of Earth Sciences
The type section of the Çal Tepe Formation, near Seydişehir, is reviewed. The basal dolomite member is unfossiliferous, but the succeeding black limestone member (24 m), light-grey limestone member (10.15 m), and red nodular limestone member (46.7 m) are subdivided into thirty-seven numbered, often fossiliferous beds. Trilobites from the black limestone member, late Early Cambrian, exhibit affinities with Morocco, Spain and northwestern Europe; they include one new genus and species (Pamphyliaspis nigra) and three other new species (Condylopyge matutina, Alueva venulosa, Antatlasia scabra). The lower light-grey limestone member contains Acadoparadoxides (Acadoparadoxides) mureroensis, basal Middle Cambrian index species in Spain, with …
Karst In Turkish Thrace: Compatibility Between Geological History And Karst Type, Mehmet Ekmekçi̇
Karst In Turkish Thrace: Compatibility Between Geological History And Karst Type, Mehmet Ekmekçi̇
Turkish Journal of Earth Sciences
Geographically, Thrace is a region located in southeastern Europe within the territories of Greece, Bulgaria and Turkey. In Turkish Thrace, karst occurs extensively in Eocene limestones, although some limited karst occurs in marble of the metamorphic series of Palaeozoic age. The karstification base is shallow to very shallow and most of the dolines and poljes have been captured by surface streams. Subsurface drainage has been changed to surface drainage in most parts of the region. Caves and cave relicts are concentrated mainly at three different altitudes, and almost all caves are horizontal or sub-horizontal. With these characteristics, Turkish Thrace hosts …
Shape And Size Characteristics Of Bedload Transported During Winter Storm Events In The Cwm Treweryn Stream, Brecon Beacons, South Wales, Tuncer Demi̇r, R. P. D. Walsh
Shape And Size Characteristics Of Bedload Transported During Winter Storm Events In The Cwm Treweryn Stream, Brecon Beacons, South Wales, Tuncer Demi̇r, R. P. D. Walsh
Turkish Journal of Earth Sciences
Bedload transport in the Cwm Treweryn stream, a tributary of the Usk in the Brecon Beacons, South Wales, was investigated during a wet winter period in early 1995 using basket-type bedload traps and the tracing of painted clasts. The Cwm Treweryn is a typical mountain stream of the region with its gravel-bedload, flashy regime, high gradient and pool-riffle sequences. In particular, the study explored - for a range of categories of clast size - the nature of any influence of clast shape on bedload movement. Competent flows ranging from 2.5 to 19.5 m^3 s^{-1} (the latter close to bankfull flow) …
Genetic Relations Between Skarn Mineralization And Petrogenesis Of The Evciler Granitoid, Kazdağ, Çanakkale, Turkey And Comparison With World Skarn Granitoids, Yeşi̇m Yücel Öztürk, Cahi̇t Helvaci, Muharrem Satir
Genetic Relations Between Skarn Mineralization And Petrogenesis Of The Evciler Granitoid, Kazdağ, Çanakkale, Turkey And Comparison With World Skarn Granitoids, Yeşi̇m Yücel Öztürk, Cahi̇t Helvaci, Muharrem Satir
Turkish Journal of Earth Sciences
Most skarn deposits are directly related to magmatic activity, and there is a systematic correlation between the composition of causative plutons and the metal contents of the related skarns. This paper documents the composition of facies within the Evciler pluton and correlations between intrusion composition and the metal contents of associated skarns. There have been previous studies of mines (e.g., Cu mines) in the Evciler district, however, there have been no detailed geological investigations of such ore deposits or associated skarn mineralization. In the Evciler district both calcic exoskarn (garnet-pyroxene) and endoskarn (pyroxene-epidote) occur along the contacts between granitoid and …
Crystal Structure Of The Cis-Bis[4-Chloro-N-(Pyrrolidine-1-Carbothioyl)-Benzamido] Copper(Ii) Complex, Nevzat Külcü, Ulrich Flörke, Hakan Arslan
Crystal Structure Of The Cis-Bis[4-Chloro-N-(Pyrrolidine-1-Carbothioyl)-Benzamido] Copper(Ii) Complex, Nevzat Külcü, Ulrich Flörke, Hakan Arslan
Turkish Journal of Chemistry
The crystal and molecular structure of the cis-bis[4-chloro-N-(pyrrolidine-1-carbothioyl)-benzamido] copper(II) complex was determined by single-crystal X-ray diffraction. The title compound, C_{24}H_{24}N_4O_2 S_2Cl_2Cu, crystalizes in the triclinic space group P-1, with Z = 4 and unit cell parameters a = 8.3877(5) Å, b = 12.7904(8) Å, c = 24.160(2) Å, \alpha = 95.923(1) °, \beta = 96.001(1) °, and \gamma = 95.048(1) °. The copper atom is 4-fold coordinated by 2 S and 2 O atoms and shows a slightly distorted planar quadratic ligand arrangement.
Diels-Alder Reactions Of New Methoxysubstituted-6-Arylfulvenes, Nüket Öcal, Emi̇ne Bağdatli, Mesut Arslan
Diels-Alder Reactions Of New Methoxysubstituted-6-Arylfulvenes, Nüket Öcal, Emi̇ne Bağdatli, Mesut Arslan
Turkish Journal of Chemistry
Fulvenes 1, 2 and 3 were prepared and their Diels-Alder cycloaddition reactions with maleic anhydride, N-phenylmaleimide and dimethyl acetylenedicarboxylate (DMAD) as dienophiles leading to endo- and exo- [4+2] adducts shown.
Determination Of Trace Copper By Faas After Solid Phase Extraction And Preconcentration Onto Amberlite Xad-2 Loaded With Nitroso-R Salt, Mohammad Ali Taher, Sayed Ziae Mohammadi Mobarakeh, Ali Reza Mohadesi
Determination Of Trace Copper By Faas After Solid Phase Extraction And Preconcentration Onto Amberlite Xad-2 Loaded With Nitroso-R Salt, Mohammad Ali Taher, Sayed Ziae Mohammadi Mobarakeh, Ali Reza Mohadesi
Turkish Journal of Chemistry
A procedure for the separation and preconcentration of trace amounts of copper is proposed. It is based on the adsorption of copper(II) ions solution onto a column of Amberlite XAD-2 resin loaded with disodium 1-nitroso-2-naphthol-3, 6-disulfonate (nitroso-R salt). Copper is quantitatively retained on the column in the pH range 5.5-7.8 at a flow rate of 2 mL min^{-1}. The copper complex eluted with 5 mL of dimethylformamide (DMF) and copper was measured by flame atomic absorption spectrometry (FAAS) at 324.8 nm. In this case, 0.10 \mu g of copper can be concentrated in the column from 800 mL of aqueous …
Development And Characterization Of A Cationic Emulsion Formulation As A Potential Pdna Carrier System, Kudret Di̇lşat Barut, Fatma Fi̇li̇z Coşkun Ari, Fi̇li̇z Öner
Development And Characterization Of A Cationic Emulsion Formulation As A Potential Pdna Carrier System, Kudret Di̇lşat Barut, Fatma Fi̇li̇z Coşkun Ari, Fi̇li̇z Öner
Turkish Journal of Chemistry
The development of efficient and stable carriers for the delivery of DNA to the body is becoming an increasingly important issue in the fields of gene therapy and vaccination. The present study was designed to prepare an emulsion-based gene delivery system. Oil-in-water emulsions containing cetyltrimethylammonium bromide (CTAB) as a cationic surfactant and Pluronic F-68 as a nonionic co-surfactant were formulated and their physical characteristics were investigated. The cationic emulsion, referred to as B13d, containing a liquid crystal phase, was found to be stable and suitable for parenteral application. Complex formation between pGL3 plasmid DNA and B13d emulsion achieved at the …
Potentiometric Studies On The Protonation Constants And Solvation Of Some \Alpha-Amino Acid Benzyl- And T-Butyl- Esters In Ethanol-Water Mixtures, Alev Doğan, Esma Kiliç
Potentiometric Studies On The Protonation Constants And Solvation Of Some \Alpha-Amino Acid Benzyl- And T-Butyl- Esters In Ethanol-Water Mixtures, Alev Doğan, Esma Kiliç
Turkish Journal of Chemistry
To gain more information about the effect of solvent on \alpha -amino acid benzyl- and t-butyl- esters, the stoichiometric protonation constants of 10 esters (glycine benzyl ester, L-alanine benzyl ester, L-valine benzyl ester, L-serine benzyl ester, glycine t-butyl ester, L-alanine t-butyl ester, L-valine t-butyl ester, L-leucine t-butyl ester, L-phenylalanine t-butyl ester and L-isoleucine t-butyl ester) in 20%-80% (v/v) ethanol-water mixtures were determined at an ionic strength of 0.10 M NaCl and at 25.0 \pm 0.1 °C under nitrogen atmosphere. A potentiometric method was used and the calculation of constants was carried out using the PKAS computer program. The logarithm of …
Synthesis And Characterization Of Novel Hyperbranched Polyimides Based On Silsesquioxane Nanocomposite Networks, Turgay Seçki̇n, Ahmet Gültek, Süleyman Köytepe
Synthesis And Characterization Of Novel Hyperbranched Polyimides Based On Silsesquioxane Nanocomposite Networks, Turgay Seçki̇n, Ahmet Gültek, Süleyman Köytepe
Turkish Journal of Chemistry
A series of nanosized polyimides was successfully prepared by condensation polymerization of an octaamino-functionalized silsesquioxane and a series of commercially available dianhyride monomers. The polymerization of the octaamino silsesquioxane was carried out in 1-methyl-2-pyrrolidone (NMP) at room temperature, giving poly(amic acid) as precursor polymers that were readily converted to the corresponding polyimides by thermal treatment in the subsequent step, which is similar to the conventional 2-stage method. The appropriate molar ratio of the silsesquioxane monomer to a dianhyride was 1:1. These polyimides are readily soluble in polar aprotic solvents such as 1-methyl-2-pyrrolidone, and N,N-dimethylacetamide at room temperature, and show high …
Kaurane Diterpenoids From Three Sideritis Species, Maurizio Bruno, Franco Piozzi, Nelly Apostolides Arnold, K. Hüsnü Can Başer, Nurhayat Tabanca, Neşe Kirimer
Kaurane Diterpenoids From Three Sideritis Species, Maurizio Bruno, Franco Piozzi, Nelly Apostolides Arnold, K. Hüsnü Can Başer, Nurhayat Tabanca, Neşe Kirimer
Turkish Journal of Chemistry
Some kaurane diterpenoids were isolated from 3 species of the genus Sideritis (Lamiaceae) growing in the Eastern Mediterranean region. Sideritis libanotica subsp. libanotica contained siderol 2 and sideridiol 3. Sideritis erythrantha var. erythrantha yielded sideridiol 3. Sideritis perfoliata gave siderol 2, sideridiol 3 and sideritriol 4. The products are known as they occur in another species of Sideritis growing in Italy and in other species growing also in Turkey. The products are isolated for the first time from these 3 species. The taxonomic significance of these results is discussed.
Flavonoids From The Leaves Of Impatiens Bicolor, Aurangzeb Hasan, Muhammad Nawaz Tahir
Flavonoids From The Leaves Of Impatiens Bicolor, Aurangzeb Hasan, Muhammad Nawaz Tahir
Turkish Journal of Chemistry
Three new flavanone glycosides, naringenin 4'-O-\beta-D-glucuronopyranoside, naringenin 4'-O-\alpha-L rham\-nopyranoside and naringenin 4'-O-\beta-D-xylopyranoside, were characterized from the leaves of Impatiens bicolor, together with 6 known glycosides: naringenin 4'-O-\beta-D-glucopyranoside, kaempferol 7-O-\beta-D-glucuronopyranoside, quercetin 3-O-\beta-D-glucopyranoside, kaempferol 5-O-\beta-D-xylopyranoside, kaempferol 3-O-\beta-D-galactopyranoside and kaempferol 7-O-\beta-D-xylopyranoside. The structures were determined by means of co-chromatography, UV, HPLC, EI-MS, FAB-MS and ^1H NMR.
Secondary Metabolites Of Phlomis Viscosa And Their Biological Activities, İhsan Çaliş, Hasan Kirmizibekmez, John A. Beutler, Ali̇ Arslan Dönmez, Funda Nuray Yalçin, Ekrem Kiliç, Meral Özalp, Peter Rüedi, Deni̇z Taşdemi̇r
Secondary Metabolites Of Phlomis Viscosa And Their Biological Activities, İhsan Çaliş, Hasan Kirmizibekmez, John A. Beutler, Ali̇ Arslan Dönmez, Funda Nuray Yalçin, Ekrem Kiliç, Meral Özalp, Peter Rüedi, Deni̇z Taşdemi̇r
Turkish Journal of Chemistry
Further phytochemical studies on the aerial parts of Phlomis viscosa (Lamiaceae) led to the isolation of 24 compounds: 3 iridoid glycosides, 10 phenylethanoid glycosides, a megastigmane glycoside and a hydroquinone glycoside, as well as 2 lignan glucosides and 7 neolignan glucosides, 1 of which is new (17b). Compound 17b was obtained as a minor component of an inseparable mixture (2:1) of 2 neolignan glucosides (17a/b), and characterized as 3',4-O-dimethylcedrusin 9-O-\beta -glucopyranoside. Full NMR data of the known 8-O-4' neolignan glucoside, erythro-1-(4-O-\beta-glucopyranosyl-3-methoxyphenyl)- 2-{2-methoxyl-4-[1-(E)-propene-3-ol]-phenoxyl}-propane-1,3-diol (18) are also reported. All isolated compounds were screened for cell growth inhibition versus 3 tumor cell lines …