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Catalytic Spectrophotometric Determination Of Manganese In Some Medicinal Plants And Their Infusions, Kostantin L. Mutaftchiev
Catalytic Spectrophotometric Determination Of Manganese In Some Medicinal Plants And Their Infusions, Kostantin L. Mutaftchiev
Turkish Journal of Chemistry
The catalytic effect of manganese (II) on the oxidation of the dye 1,3-Dimethyl- 2 [4-N (N,N-dimethylamino) phenylazo] imidazolium perchlorate (BR) with potassium periodate in the presence of 1,10-phenanthroline was investigated. The reaction was followed spectrophotometrically by measuring the decrease in the absorbance of the dye at 540 nm. Under optimum conditions (5 \times 10^{-5} mol dm^{-3} BR, 2 \times 10^{-4} mol dm^{-3} potassium periodate, 1 \times 10^{-4} mol dm^{-3} 1,10-phenanthroline, 0.1 mol dm^{-3} buffer -- pH 3.0, 70 °C, 5 min) manganese (II) in the range 0.1--4.5 ng cm^{-3} can be determined by the fixed-time method with a detection limit …
Study On Papain Immobilization On A Macroporous Polymer Carrier, Liang Ding, Zihua Yao, Tong Li, Qiang Yue, Jia Chai
Study On Papain Immobilization On A Macroporous Polymer Carrier, Liang Ding, Zihua Yao, Tong Li, Qiang Yue, Jia Chai
Turkish Journal of Chemistry
Macroporous resin microbeads of methyl methacrylate-divinyl benzene copolymer were synthesized by radical suspension polymerization of acrolein with divinylbenzene in the presence of a pore-creating agent, petroleum ether. The microbeads had a large specific surface area and large pores covered the entire surface of the resin. This macroporous polymer carrier was aminated by hydrazine hydrate that produced a large number of amino groups on the carrier. Papain was immobilized on the porous polymer carrier by glutaraldehyde cross-linking or diazo-coupling. The factors involved in the activity recovery of the immobilized papain and the enzymic properties of the resulting immobilized papain were studied …
Adsorption Of Arsenate And Chromate From Waters On Hydrophobized Zeolitic Media, Eva Chmielewska
Adsorption Of Arsenate And Chromate From Waters On Hydrophobized Zeolitic Media, Eva Chmielewska
Turkish Journal of Chemistry
A laboratory setup was used to examine the uptake of chromate and arsenate from aqueous solutions by octadecylammonium acetate [ODA]-modified inland clinoptilolite. In trials, a natural variety of montmorillonite was compared to organic, i.e. surfactant loaded clinoptilolite. and some inorganically substituted (Ag, Pb) monoforms. The arrangement of the surface-attached ODA chains was the important factor for differences in the adsorption states of the guest species (oxyanions). A novel nano-structure inorganic-organic composite was prepared and was characterized by SEM, thermogravimetry, HR TEM, UV-VIS diffuse reflectance and powder XRD spectral analytical methods. Finally, the adsorption isotherms of the studied system were expressed. …
Solid Phase Extraction Of Copper(Ii) By Modified Octadecyl Silica Membrane Disks With 3-{2-[2-(2-Hydroxyimino-1-Methyl-Propylideneamino)- Ethylamino]-Ethyl-Imino}-Butan-2-One~Oxime, Ömer Dalman, Serdar Karaböcek, Ahmet Demi̇rak, Mehmet Tüfekçi̇
Solid Phase Extraction Of Copper(Ii) By Modified Octadecyl Silica Membrane Disks With 3-{2-[2-(2-Hydroxyimino-1-Methyl-Propylideneamino)- Ethylamino]-Ethyl-Imino}-Butan-2-One~Oxime, Ömer Dalman, Serdar Karaböcek, Ahmet Demi̇rak, Mehmet Tüfekçi̇
Turkish Journal of Chemistry
A simple, selective and rapid method for determining trace amounts of copper(II) ions in various types of water samples using atomic absorption spectrophotometry was investigated. Copper(II) ions from water samples were preconcentrated by solid phase extraction using octadecyl silica membrane disks modified with 3-{2-[2-(2-hydroxyimino- 1-methyl-propylideneamino)-ethylamino]-ethyl-imino}-butan-2-one oxime, (H_{2}mdo). The experimental conditions were optimized by changing several parameters such as volume of eluting solvent, the effect of pH, eluent flow rates, the amount of H_2mdo, breakthrough the volume, limit of detection and maximum capacity of the disks for Cu^{2+} recovery. The method was applied to the recovery of Cu(II) ions from seven …
Potentiometric And Spectroscopic Studies With Chromium(Iii) Complexes Of Hydroxysalicylic Acid Derivatives In Aqueous Solution, M. Suat Aksoy, Ulvi̇ye Özer
Potentiometric And Spectroscopic Studies With Chromium(Iii) Complexes Of Hydroxysalicylic Acid Derivatives In Aqueous Solution, M. Suat Aksoy, Ulvi̇ye Özer
Turkish Journal of Chemistry
The stoichiometries and stability constants of the chromium(III) complexes of hydroxysalicylic acid ligands (2,x-dihydroxy benzoic acids; 2,x-DHBA, x = 4-6)(H_3L) were determined in aqueous solution by potentiometry and spectroscopy at 25 °C and at an ionic strength of 0.1 mol L^- (KNO_3). The existence of Cr(HL)^+ type complex was verified. The stability constants of coordination species that exist in Cr(III):2,x-DHBA systems were defined. In the acidic medium the major coordination species involve salicylate type coordination. The formation of monohydroxo complexes was observed at higher pH values.
Investigation Of The Surface Acidity Of A Bentonite Modified By Acid Activation And Thermal Treatment, Tülay Alemdaroğlu, Gülcan Akkuş, Müşerref Onal, Yüksel Sarikaya
Investigation Of The Surface Acidity Of A Bentonite Modified By Acid Activation And Thermal Treatment, Tülay Alemdaroğlu, Gülcan Akkuş, Müşerref Onal, Yüksel Sarikaya
Turkish Journal of Chemistry
The adsorption of n-butylamine from its solution in cyclohexane on acid-activated and thermally treated Kütahya/Turkey bentonite (KB) samples was followed using a UV-VIS spectrophotometric method. The experimental data were evaluated by the Langmuir adsorption equation and the total number of surface acid centers (n_{m/mol} g^{-1}) was determined. The variation in n_m values as a function of the mass percent of H_2SO_4 used in activation (10%-70%) and its correlation with variations in surface area (A) and pore volume (V) as a function of the mass percent of H_2SO_4 were investigated for acid- activated KB samples. The variation in n_m values as …
Isolation And Characterization Of A Smectite As A Micro-Mesoporous Material From A Bentonite, Müşerref Önal, Yüksel Sarikaya, Tülay Alemdaroğlu, İhsan Bozdoğan
Isolation And Characterization Of A Smectite As A Micro-Mesoporous Material From A Bentonite, Müşerref Önal, Yüksel Sarikaya, Tülay Alemdaroğlu, İhsan Bozdoğan
Turkish Journal of Chemistry
A procedure was assessed for obtaining an optimum amount of a micro-mesoporous material known as smectite from Reşadiye (Tokat/Turkey) bentonite. The procedure, which will permit a better economic evaluation of the Reşadiye reserves, is based on successive settlements of bentonite suspensions during various time intervals. To characterize the original bentonite, its fractions and the high purity smectite product, X-ray diffraction, differential thermal analysis, thermogravimetric analysis, scanning electron microscopy and nitrogen adsorption-desorption techniques were used. The original bentonite contained 50% by mass sodium-rich smectite (NaS) and 10% by mass NaCa-smectite (NaCaS). It also contained illite, clinoptilolite, analcime, feldspar, calcite, dolomite, quartz …
Kinetics Of Oxidation Of Pyridylmethylsulphinylbenzimidazole By Cerium(Iv) In An Aqueous Perchloric Acid Medium, Dinesh C. Bilehal, Ravi̇raj M. Kulkarni, Sharanappa T. Nandibewoor
Kinetics Of Oxidation Of Pyridylmethylsulphinylbenzimidazole By Cerium(Iv) In An Aqueous Perchloric Acid Medium, Dinesh C. Bilehal, Ravi̇raj M. Kulkarni, Sharanappa T. Nandibewoor
Turkish Journal of Chemistry
The kinetics of oxidation of pyridylmethylsulphinylbenzimidazole [PMSB] by Ce(IV) in an aqueous perchloric acid medium at a constant ionic strength of 1.50 mol dm^{-3} were studied spectrophotometrically. The reaction showed first order kinetics with respect to Ce(IV) concentration and an apparent less than unit order dependence in [PMSB] and a zero order in [H^+]. The initial addition of products has no significant effect on the rate of the reaction. A possible mechanism is proposed here. The reaction constants involved in the mechanism have been computed. There is good agreement between the observed and calculated rate constants under different experimental conditions. …
Phenolic, Megastigmane, Nucleotide, Acetophenon And Monoterpene Glycosides From Phlomis Samia And P. Carica, Funda Nuray Yalçin, Tayfun Ersöz, Pinar Akbay, İhsan Çaliş, Ali̇ Arslan Dönmez, Otto Sticher
Phenolic, Megastigmane, Nucleotide, Acetophenon And Monoterpene Glycosides From Phlomis Samia And P. Carica, Funda Nuray Yalçin, Tayfun Ersöz, Pinar Akbay, İhsan Çaliş, Ali̇ Arslan Dönmez, Otto Sticher
Turkish Journal of Chemistry
Phytochemical investigations on the aerial parts of Phlomis samia resulted in the isolation of a simple phenolic glucoside, 2,6-dimethoxy-4-hydroxyphenol-1-O-\beta -D-glucopyranoside (1); a megastigmane glucoside, phlomuroside (=3-hydroxy-5,6-epoxy-\beta -ionol-9-O-\beta -D-glucopyranoside) (2); and a nucleotide glycoside, uridine (3). From the aerial parts of P. carica, the same phenolic glucoside, 2,6-dimethoxy-4-hydroxyphenol-1-O-\beta -D-glucopyranoside (1); as well as an acetophenon glucoside, picein (4); and 2 monoterpenoid glucosides, - betulalbuside A (5) and 1-hydroxylinaloyl-6-O-\beta -D-glucopyranoside (6) - were isolated and identified. The structure elucidation of the isolates was based on spectroscopic evidence.
Application Of Ibx Method For The Synthesis Of Ketones From Carboxylic Acids, H. R. Ferhat Karabulut, Mesut Kaçan, Hasan Özyildirim
Application Of Ibx Method For The Synthesis Of Ketones From Carboxylic Acids, H. R. Ferhat Karabulut, Mesut Kaçan, Hasan Özyildirim
Turkish Journal of Chemistry
Methoxy phenyl propionic acid and some derivatives are converted to ketones using a new method. All classical methods to obtain ketones from carboxylic acids via acid halide consistently gave very low yields and regularly generated intermolecular cyclisation products or polymeric materials. However, high ketones yields are obtained by using the new IBX method.
Application Of Potassium Chromate-Diphenylcarbazide In The Quantitative Determination Of Ascorbic Acid By Spectrophotometry, Meissam Noroozifar, M. Khorasani Motlagh
Application Of Potassium Chromate-Diphenylcarbazide In The Quantitative Determination Of Ascorbic Acid By Spectrophotometry, Meissam Noroozifar, M. Khorasani Motlagh
Turkish Journal of Chemistry
A spectrophotometric procedure for the determination of ascorbic acid in pure form and in a number of pharmaceutical preparations and real samples has been developed that offers the advantages of simplicity, accuracy, precision and sensitivity over many other methods. The method is based on the oxidation of ascorbic acid by a known excess amount of potassium chromate followed by the estimation of the unreacted amount of chromate by reactions with sym-diphenylcarbazide. The reacted oxidant corresponds to the ascorbic content. At the maximum absorption of 548 nm, Beer's law is obeyed up to 5 \mu g/mL of ascorbic acid. Statistical treatment …
The Composition Of Fatty Acids In Hypericum Scabrum, H. Scabroides And H. Amblysepalum, Hasan Çeti̇n Özen, Mehmet Başhan
The Composition Of Fatty Acids In Hypericum Scabrum, H. Scabroides And H. Amblysepalum, Hasan Çeti̇n Özen, Mehmet Başhan
Turkish Journal of Chemistry
The chemical composition of the fatty acid methyl esters (FAMEs) of flowering tops of Hypericum scabrum, H. scabroides and H. amblysepalum were identified by gas chromatography. In this work 5 FAMEs for H. scabrum, 9 FAMEs for H. scabroides and 8 FAMEs for H. amblysepalum were identified. The major components were alpha-linolenic (48.60%), linoleic (32.53%) and oleic (11.45%) acids in H. scabrum. Alpha-linolenic (29.84%), palmitic (27.90%) and oleic (16.49%) acids were present in H. scabroides and alpha linolenic (41.79%) and palmitic acids (32.28%) were found in H. amblysepalum.
Synthesis And Analgesic And Anti-Inflammatory Activity Of New Pyridazinones, Deni̇z S. Doğruer, M. Fethi̇ Şahi̇n, Esra Küpeli̇, Erdem Yeşi̇lada
Synthesis And Analgesic And Anti-Inflammatory Activity Of New Pyridazinones, Deni̇z S. Doğruer, M. Fethi̇ Şahi̇n, Esra Küpeli̇, Erdem Yeşi̇lada
Turkish Journal of Chemistry
A new series of 2-(6-oxo-3,5-diphenyl-6H-pyridazin-1-yl)- acetamides and 3-[6-oxo-3,5-diphenyl-6H-pyridazin-1-yl)-propanamides were synthesized and evaluated in terms of their analgesic and anti-inflammatory activities. All compounds except for 7g were more potent than aspirin in a p-benzoquinone--induced writhing test at 100 mg/kg dose. Compounds 7b, 7c and 7e had the highest anti-inflammatory activity; compound 7e was the most potent in terms of analgesic and anti-inflammatory activities and had no ulcerogenic side effects.
Neolignan, Flavonoid, Phenylethanoid And Iridoid Glycosides From Phlomis Integrifolia, İclal Saracoğlu, Mehtap Varel, İhsan Çaliş, Ali̇ Arslan Dönmez
Neolignan, Flavonoid, Phenylethanoid And Iridoid Glycosides From Phlomis Integrifolia, İclal Saracoğlu, Mehtap Varel, İhsan Çaliş, Ali̇ Arslan Dönmez
Turkish Journal of Chemistry
From the aerial parts of Phlomis integrifolia Hub.-Mor. (Lamiaceae) were isolated a neolignan glucoside, dehyrodiconiferyl alcohol-4-O-\beta -D-glucopyranoside (1), an ester flavone glycoside, chrysoeriol 7-O-(3''-O-trans-p-coumaroyl)-\beta -D-glucopyranoside (2), four phenylethanoid glycosides, forsythoside B (3), verbascoside (=acteoside) (4), leucosceptoside A (5) and martynoside (6) along with an iridoid glucoside, lamiide (7). The structure elucidation of the isolated compounds was carried out by spectroscopic (UV, IR, 1D- and 2D-NMR) methods. The isolation of neolignan glucoside dehyrodiconiferyl alcohol-4-O-\beta -D-glucopyranoside (1) is reported for the first time from a Phlomis species as well as for the family Lamiaceae.
Chemical Constituents Of Campanula Lactiflora, Nuretti̇n Yayli, Nuri̇ Yildirim, Asu Usta, Serpi̇l Özkurt, Vi̇ldan Akgün
Chemical Constituents Of Campanula Lactiflora, Nuretti̇n Yayli, Nuri̇ Yildirim, Asu Usta, Serpi̇l Özkurt, Vi̇ldan Akgün
Turkish Journal of Chemistry
A new flavonoid glycoside, 4'-O-(p-hydroxybenzoyl)-isorhamnetin-3,7- di-O-\beta-D-glucopyranoside (1), and 4 known compounds, sitosterol \beta-D-glucoside (2), bis(2-ethylhexyl) adipate (3), p-hydroxybenzoic acid (4) and ethyl docosanoate (5), were isolated for the first time from Campanula lactiflora and their structures were deduced by high field 1D and 2D NMR and (+) FAB and EI mass spectra.
Synthesis And Evaluation Of Antimicrobial Activity Of New 3-Hydroxy-6-Methyl-4-Oxo-4h-Pyran-2- Carboxamide Derivatives, Mutlu Di̇lsi̇z Aytemi̇r, Di̇lek Demi̇r Erol, Robert Charles Hider, Meral Özalp
Synthesis And Evaluation Of Antimicrobial Activity Of New 3-Hydroxy-6-Methyl-4-Oxo-4h-Pyran-2- Carboxamide Derivatives, Mutlu Di̇lsi̇z Aytemi̇r, Di̇lek Demi̇r Erol, Robert Charles Hider, Meral Özalp
Turkish Journal of Chemistry
The synthesis of a range of 3-hydroxy-4-oxo-4H-pyran-2- carboxamide with antimicrobial activity is described. Amide derivatives of pyranone were synthesised using TBTU [2-(1H-benzotriazol-1-yl)-1,1,3,3-tetramethyluronium tetrafluoroborate] as a coupling agent and NMM (N-methylmorpholine) as a base. Antimicrobial activities were determined as MIC values using the microdilution broth method against Staphylococcus aureus, Entrococcus faecalis, Escherichia coli and Pseudomonas aeruginosa for bacteria and Candida albicans, C. krusei and C. parapsilosis for fungi. 3-Hydroxy-6-methyl-4-oxo-4H-pyran-2-[N-(4'-methylcoumarin-7-yl) carboxamide] (8c) exhibited higher antibacterial activity against S. aureus, E. faecalis and E. coli than the other compounds. In addition, 8c was more active against C. krusei than the other synthesised compounds.
6-O-\Alpha-L-Rhamnopyranosylcatalpol Derivative Iridoids From Verbascum Cilicicum, İ. İrem Tatli, Zeli̇ha Ş. Akdemi̇r, Erdal Bedi̇r, Ikhlas A. Khan
6-O-\Alpha-L-Rhamnopyranosylcatalpol Derivative Iridoids From Verbascum Cilicicum, İ. İrem Tatli, Zeli̇ha Ş. Akdemi̇r, Erdal Bedi̇r, Ikhlas A. Khan
Turkish Journal of Chemistry
From the aerial parts of Verbascum cilicicum Boiss., 6 iridoid glycosides, namely catalpol (1), verbaspinoside [= 6-O-(2'' -O-trans-cinnamoyl)-\alpha-L-rhamnopyranosylcatalpol] (2), 6-O-(3''-O-trans-cinna\-moyl)-\alpha-L-rhamnopyranosylcatalpol (3), 6-O-(4''-O-trans-cinnamoyl)-\alpha -L-rhamnopyranosylcatalpol (4), saccatoside [= 6-O-(2''-O-trans-p-coumaroyl)-\alpha-L-rhamnopyranosylcatalpol] (5), and 6-O-(3''-O-trans-p-coumaroyl)-\alpha-L-rhamnopyranosylcatalpol (6), were isolated. The structures of the compounds were elucidated by means of 1 and 2 dimensional (DQF-COSY, HMQC and HMBC) NMR techniques and LC-ESIMS.
Plasticiser Effect On Water Vapour Permeability Properties Of Locust Bean Gum--Based Edible Films, Özgür Altan Bozdemi̇r, Mehmet Tutaş
Plasticiser Effect On Water Vapour Permeability Properties Of Locust Bean Gum--Based Edible Films, Özgür Altan Bozdemi̇r, Mehmet Tutaş
Turkish Journal of Chemistry
The barrier properties of edible films prepared from polysaccharide polymer (locust bean gum) and various plasticisers (glycerol, propylene glycol, sorbitol, and polyethylene glycol 200) together with hydrophobic modifiers (stearopten and beeswax) were examined. It was determined that the films containing polyethylene glycol 200 (PEG 200) and sorbitol have the lowest water vapour permeability values and the films containing glycerol have the highest WVP values. It was found that the most reasonable of the studied plasticisers was PEG 200. Polysaccharide--based edible films have higher WVP values than those of lipid-- and protein--based edible films. In order to reduce the WVP of …
Growth Mechanism And Some Properties Of Cd_{1-X}Mn_X Se Semimagnetic Semiconductor Thin Films, V. S. Karande, S. H. Mane, Vithal Bhivaba Pujari, L. P. Deshmukh
Growth Mechanism And Some Properties Of Cd_{1-X}Mn_X Se Semimagnetic Semiconductor Thin Films, V. S. Karande, S. H. Mane, Vithal Bhivaba Pujari, L. P. Deshmukh
Turkish Journal of Physics
(Cd, Mn) Se dilute semiconductor or semimagnetic semiconductors have recently became the focus of intense research due to their interesting combination of magnetic and semiconducting properties, and are employed in a variety of devices including solar cells, gas sensors etc. A series of thin films of this material, Cd_{1 - x}Mn_xSe (0 \le x \le 0.5), were therefore synthesized onto precleaned amorphous glass substrates using a solution growth technique. The sources of cadmium (Cd^{2+}) and manganese (Mn^{2+}) were aqueous solutions of cadmium sulphate and manganese sulphate, and selenium (Se^{2-}) was extracted from a reflux of sodium selenosulphite. The different deposition …
First Records Of Conodonts From "The Permo-Carboniferous Of Demirözü" (Bayburt), Eastern Pontides, Ne Turkey, Şenol Çapkinoğlu
First Records Of Conodonts From "The Permo-Carboniferous Of Demirözü" (Bayburt), Eastern Pontides, Ne Turkey, Şenol Çapkinoğlu
Turkish Journal of Earth Sciences
Permo-Carboniferous sedimentary rocks, which belong to the pre-Jurassic basement of the Eastern Pontides, occur in the Cebre relative autochthon and the Hamurkesen thrust sheet in the Demirözü area, Bayburt, NE Turkey, and consist of the Çatalçeşme and Hardişi formations, respectively. Some limestone beds of the Çatalçeşme Formation in the village of Çatalçeşme produced the first conodont faunas encountered in Palaeozoic sediments of the Eastern Pontides. A rich conodont fauna with abundant Neognathodus bassleri (HARRIS & HOLLINGSWORTH), less Idiognathodus sp. and Streptognathodus elegantulus STAUFFER & PLUMMER, and rare Gondolella sp. were obtained from a densely-packed bioclastic packstone bed on the west …
Improving The Security And Flexibility Of One-Time Passwords By Signature Chains, Kemal Biçakci, Nazi̇fe Baykal
Improving The Security And Flexibility Of One-Time Passwords By Signature Chains, Kemal Biçakci, Nazi̇fe Baykal
Turkish Journal of Electrical Engineering and Computer Sciences
While the classical attack of ``monitor the network and intercept the password'' can be avoided by advanced protocols like SSH, one-time passwords are still considered a viable alternative or a supplement for software authentication since they are the only ones that safeguard against attacks on insecure client machines. In this paper by using public-key techniques we present a method called signature chain alternative to Lamport's hash chain to improve security and flexibility of one-time passwords. Our proposition improves the security because first, like other public-key authentication protocols, the server and the user do not share a secret, thereby eliminating attacks …
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.