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Determination Of Optical Constant Of Materials By Two Different Methods: An Application To Single Crystals Si, Hazi̇ret Durmuş, Haluk Şafak, Haldun Karabiyik Jan 2000

Determination Of Optical Constant Of Materials By Two Different Methods: An Application To Single Crystals Si, Hazi̇ret Durmuş, Haluk Şafak, Haldun Karabiyik

Turkish Journal of Physics

The normal reflectance of single crystal Si was measured at 0.5 ­5.6 eV range by unpolarized light. Optical parameters of Si were determined from this reflectance data by using two different methods: oscillator fit procedure and Kramers-Kronig analysis. The refractive index, extinction coefficient and the real and imaginary parts of complex dielectric constant obtained by these two methods were compared. A good agreement was found between two methods. Furthermore, the optical parameters so obtained seem to be in a satisfactory agreement with the literature.


Crystallographic Analysis Of Martensitic Transformation In Cusn Alloy, Ekrem Artunç, Seyfetti̇n Çakmak, Seval Çakmak Jan 2000

Crystallographic Analysis Of Martensitic Transformation In Cusn Alloy, Ekrem Artunç, Seyfetti̇n Çakmak, Seval Çakmak

Turkish Journal of Physics

In this study, the Kajiwara model has been applied to Cu-14.8at.\%Sn alloy with good agreement with experimental results. For this alloy, the austenite phase has a body centered cubic (bcc) lattice and the martensite phase has a monoclinic 9R superlattice. Using the lattice parameters of both phases, the calculated habit plane indices, magnitude of the lattice invariant shear and orientation relationships, have been compared with the observed results for this alloy.


A Product Operator Formalism Of 3d J-Resolved Nmr Spectroscopy For Is_Nk_M(I = 1/2, S = 1/2, K = 1/2) Spin System, Özden Tezel, Azmi̇ Gençten Jan 2000

A Product Operator Formalism Of 3d J-Resolved Nmr Spectroscopy For Is_Nk_M(I = 1/2, S = 1/2, K = 1/2) Spin System, Özden Tezel, Azmi̇ Gençten

Turkish Journal of Physics

Product operator formalism is widely used for analytical description of multiple-pulse NMR experiments for weakly coupled spin systems. 3D J-resolved NMR spectroscopy is widely used in order to resolve the chemical shift along one axis and spin-spin coupling parameters along the two other axis. In this study, product operator theory is used for analytical description of heteronuclear 3D J-resolved NMR spectroscopy for the \( IS_nK_m (I=1/2, S=1/2, K=1/2; n=1,2, m=1,2,3) \) spin system.


Determining The Efficiency Of Forward-Sloped Bench Terraces On Soil Conservation: The Case Of The Aydın-Bozdoğan-Alamut Terracing Area, Alaetti̇n Taysun, Hali̇l Baki̇ Ünal, Altan Şahi̇n, Hasan Zafer Vurgun Jan 2000

Determining The Efficiency Of Forward-Sloped Bench Terraces On Soil Conservation: The Case Of The Aydın-Bozdoğan-Alamut Terracing Area, Alaetti̇n Taysun, Hali̇l Baki̇ Ünal, Altan Şahi̇n, Hasan Zafer Vurgun

Turkish Journal of Agriculture and Forestry

The study was carried out to determine the efficiency of forward-sloped bench terraces on soil conservation in the Aydın- Bozdoğan-Alamut terracing area. For this purpose, the shape specifications, and physical and chemical properties of the soil that belong to the sample terraces in the project area were determined and the factors of K and LS that are needed for calculating soil losses were are found through the Universal Soil Losses Equation. According to the evaluation, especially the determined factors of K and LS were higher for the sample terraces interfered with by farmers and this result shows that the probable …


Cover And Contents Jan 2000

Cover And Contents

Turkish Journal of Veterinary & Animal Sciences

No abstract provided.


Effects Of The Spiral Grain On Some Physical Properties Of Calabrian Pine (Pinus Brutiaten.) Wood, Yener Göker, Nusret As, Turgay Akbulut, Türker Dündar Jan 2000

Effects Of The Spiral Grain On Some Physical Properties Of Calabrian Pine (Pinus Brutiaten.) Wood, Yener Göker, Nusret As, Turgay Akbulut, Türker Dündar

Turkish Journal of Agriculture and Forestry

In this study, the effects of spiral grain on some physical properties of the Calabrian pine (Pinus brutia Ten.) wood were investigated. For this purpose, 17 sample trees with various spiral grain angles, were taken from the Çakirlar region, Antalya district. The selected trees were divided into five groups according to grain angles. Tests were carried out for oven dry density, density values in volume, shrinkage, fiber saturated point (FSP) and maximal moisture content. The results led to a number of conclusions; In general, density increased in relation to the spiral grain increase. Density (oven dry weight/green volume) increased after …


Effects Of Wheel Traffic Porosity And Compaction Of Soil Profile, Cevdet Şeker, A. Ali̇ Işildar Jan 2000

Effects Of Wheel Traffic Porosity And Compaction Of Soil Profile, Cevdet Şeker, A. Ali̇ Işildar

Turkish Journal of Agriculture and Forestry

The aim of this experimental study was to determine the effect on soil porosity and compaction of the number of the tractor passes on the soil surface. The soil has a sandy loam texture. A tractor passed once, twice, and four times while the water content of soil was near field capacity. Numbers of tractings increased soil bulk density and compaction, and decreased total porosity, void ratio, air porosity and drainage porosity. One and two tractor passes did not markedly affect the percentage of porosity kept at field capacity porosity, but four tractor passes improved it.


Cover And Contents Jan 2000

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.


Exploring The Concept Of A Forest Landscape Management Paradigm, Emi̇n Zeki̇ Başkent, Haci̇ Ahmet Yolasiğmaz Jan 2000

Exploring The Concept Of A Forest Landscape Management Paradigm, Emi̇n Zeki̇ Başkent, Haci̇ Ahmet Yolasiğmaz

Turkish Journal of Agriculture and Forestry

The concept of forest management planning has rapidly progressed towards a more holistic approach in the last decade. Considering the whole landscape of ecosystems is the focus of landscape management. This paper examines the evolutionary process of forest management and compares and contrasts the landscape management planning concept to its predecessor, the conventional forest resource management approach. It explains the conceptual framework, provides the principles and the improvements over the conventional management planning, and discusses different approaches towards the landscape management concept. However, the paper stresses the fact that the evolutionary process of forest management provides the basis for what …


Characterization Of Some Regosols In The Bursa Plain, Cumhur Aydinalp Jan 2000

Characterization Of Some Regosols In The Bursa Plain, Cumhur Aydinalp

Turkish Journal of Agriculture and Forestry

In the Bursa plain, Regosols are extensively cultivated soils for horticultural crops and irrigated by water from aquifers. These soils are quite widespread on the west side of the plain and developed on different types of parent materials. This research was carried out to determinate genesis and classification of the Regosols developed on calcareous colluvium material. Five soil profiles were examined in this research and their characterization included field morphology and physico-chemical analysis. The soils were classified according to the systems of FAO/Unesco (1990), FitzPatrick (1988), and USDA Soil Taxonomy (1994). The soils show high sand and calcium carbonate contents …


Transfer Of A \Beta-Glucuronidase Reporter Gene To Sugarbeet (Beta Vulgaris L.) Via Microprojectile Bombardment, Sertaç Önde, Melahat Bi̇rsi̇n, Mustafa Yildiz, Cengi̇z Sancak, Murat Özgen Jan 2000

Transfer Of A \Beta-Glucuronidase Reporter Gene To Sugarbeet (Beta Vulgaris L.) Via Microprojectile Bombardment, Sertaç Önde, Melahat Bi̇rsi̇n, Mustafa Yildiz, Cengi̇z Sancak, Murat Özgen

Turkish Journal of Agriculture and Forestry

For the transfer of a \beta -Glucuronidase (GUS) reporter gene to sugarbeet (Beta vulgaris L.) callus and leaf explants by microprojectile bombardment, various rupture disk pressures and sample plate distances were tested. By coating the pBI221.23 DNA construct over the gold particles, bombardments were carried out by the DuPont PDS-1000/He system and the results clearly indicated the superiority of leaf explants over the callus structures as targets. The sample plate distances affected the distribution pattern of the particles and the cells expressing the GUS reporter gene were noted to be aggregated in short distances whereas longer distance shots yielded better …


Cover And Contents Jan 2000

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.


Taxonomic And Paelogeographic Approaches To The Dasyclad Algae In The Upper Jurassic (Kimmeridgian)-Upper Cretaceous (Cenomanian) Peritidal Carbonates Of The Fele (Yassıbel) Area (Western Taurides, Turkey), İsmai̇l Ömer Yilmaz Jan 1999

Taxonomic And Paelogeographic Approaches To The Dasyclad Algae In The Upper Jurassic (Kimmeridgian)-Upper Cretaceous (Cenomanian) Peritidal Carbonates Of The Fele (Yassıbel) Area (Western Taurides, Turkey), İsmai̇l Ömer Yilmaz

Turkish Journal of Earth Sciences

In the Fele (Yassıbel) area in the north of Beyşehir Lake in the Western Taurides, Upper Jurassic (Kimmeridgian) - Upper Cretaceous (Cenomanian) peritidal carbonates were studied in detail. In this study, 30 species of dasyclad algae were identified and 3 new Salpingoporella species were identified within the peritidal carbonates. It was determined that they belong to 13 different genera: Acroporella, Actinoporella, Campbelliella, Clypeina, Cylindroporella, Epimastopora, Epimastoporella, Kopetdagaria, Macroporella, Otternstella, Rajkaella, Salpingoporella, and Selliporella. Salpingoporella is the dominant genus. Some of the species are new records for Turkey: Clypeina nigra, Clypeina parasolkani, Otternstella lemmensis, Salpingoporella biokovensis, Salpingoporella circassa, Salpingoporella piriniae, and …


Clinopyroxene Compositions Of The Isotropic Gabbros From The Sarıkaraman Ophiolite: New Evidence On Supra-Subduction Zone Type Magma Genesis In Central Anatolia, Kenan M. Yaliniz, M. Cemal Göncüoğlu Jan 1999

Clinopyroxene Compositions Of The Isotropic Gabbros From The Sarıkaraman Ophiolite: New Evidence On Supra-Subduction Zone Type Magma Genesis In Central Anatolia, Kenan M. Yaliniz, M. Cemal Göncüoğlu

Turkish Journal of Earth Sciences

The Sarıkaraman Ophiolite is one of the least dismembered ophiolitic units of the allochthonous Central Anatolian Ophiolites, which retains its recognizable pseudostratigraphy. The Sarıkaraman Ophiolite is represented in its lowermost part by isotropic gabbros. Within the isotropic gabbro sequence, clinopyroxenes are observed as small, colorless relicts with a cloudy appearance. In most of the samples, they are completely replaced by a successive generation of green to brown amphiboles. Clinopyroxenes display diopsitic to augitic compositions within the range of En 45 Fs 5 Wo 49 to En 50 Fs 9 Wo 41 . They are Ca-rich and Na-poor (Na 2 O


Field, Petrographic And Geochemical Features Of The Baranadağ Quartz Monzonite Of The Central Anatolian Granitoids, Turkey, Nurdan S. Aydin, A. Piril Önen Jan 1999

Field, Petrographic And Geochemical Features Of The Baranadağ Quartz Monzonite Of The Central Anatolian Granitoids, Turkey, Nurdan S. Aydin, A. Piril Önen

Turkish Journal of Earth Sciences

The Baranadağ quartz monzonite is one of the granitioid intrusions of the Central Anatolian Crystalline Complex (CACC) which represents the passive continental margin of the Anatolide-Tauride platform. Medium to coarse-grained Baranadağ quartz monzonites typically include mafic microgranular enclaves and K-feldspar megacrysts and are cut by aplitic dykes representing the youngest magmatic activity of the study area. The intrusion is mainly composed of orthoclase, plagioclase, quartz, hornblende, biotite and clinopyroxene. It displays a slightly alkaline character and relatively well-developed calc-alkaline trend. The metaluminous Baranadağ quartz monzonites show comparable field, petrographic and/or geochemical features with those of the H-type (Hybrid) granitoids of …


Biostratigraphic And Environmental Analysis Of The Upper Jurassic- Lower Cretaceous Carbonate Sequence In The Başoba Yayla Area (Trabzon, Ne Turkey), Kemal Tasli, Erol Özer, Cemi̇l Yilmaz Jan 1999

Biostratigraphic And Environmental Analysis Of The Upper Jurassic- Lower Cretaceous Carbonate Sequence In The Başoba Yayla Area (Trabzon, Ne Turkey), Kemal Tasli, Erol Özer, Cemi̇l Yilmaz

Turkish Journal of Earth Sciences

In the Başoba Yayla (Trabzon, NE Turkey) area, which is located in the Eastern Pontides northern zone, platform carbonates were deposited during the Late Jurassic-Early Cretaceous time in environments varying from intertidal/ supratidal to outer shelf. The carbonate sequence begins with a thick dolomite unit of the Late Jurassic to Early Cretaceous age. The following unit is rich in benthic foraminifers and pelecypoda shells. The foraminiferal assemblage comprising Vercorsella laurentii/camposaurii and Pseudolituonella gavonensis indicates a Late Hauterivian to Early Aptian age for this unit. The Late Aptian-Albian facies is characterized by bioclastic wackestones containing benthic foraminifers typical of outer platform …


Deformation Of Stibnites And Pyrites In The Madsan Antimony Deposit (Niğde, Turkey): Implications For Pressure-Temperatureconditions Of Local Deformation, İlkay Kuşcu, Ayhan Erler Jan 1999

Deformation Of Stibnites And Pyrites In The Madsan Antimony Deposit (Niğde, Turkey): Implications For Pressure-Temperatureconditions Of Local Deformation, İlkay Kuşcu, Ayhan Erler

Turkish Journal of Earth Sciences

The Madsan antimony deposit at the southeastern part of the Niğde province (south-central Turkey) includes a series of epithermal veins hosted by marbles and gneisses. The veins have a simple mineralogy of quartz, calcite, stibnite and pyrite as major constituents, and cinnabar occurs in trace amounts. The deposit experienced a progressive deformation evidenced by a set of textures developed especially in stibnite and pyrite. These are pressure lamellae and annealing as the main textures, and curvature, off-set of pressure lamellae and fracture filling as the textures of minor importance. These were developed in three successive deformation phases. Pressure lamellae represent …


Diurnal Variation Of Water Chemistry Andzooplankton In Little Mere, Cheshire, Uk, In 1993 And 1994, Meryem Bekli̇oğlu, Brian Moss Jan 1999

Diurnal Variation Of Water Chemistry Andzooplankton In Little Mere, Cheshire, Uk, In 1993 And 1994, Meryem Bekli̇oğlu, Brian Moss

Turkish Journal of Zoology

In Little Mere, diurnal sampling of the zooplankton at three different habitats in 1993 provided little evidence to support the data of Timms and Moss (10) that cladocerans move out from refugia at night to graze in open water. The floating-leaved water lily, appeared to be more efficient at providing refuge to D. hyalina in the presence of high planktivore fish predation than the submerged plant beds and the open water. This might be due to unfavourable physical and chemical environmental conditions associated with the water lily bed for fish feeding, a possibility supported by the findings of very low …


Some Biological Characteristics Of Artemia Salina (L., 1758) In Tuz Lake, Yasemi̇n Başbuğ Jan 1999

Some Biological Characteristics Of Artemia Salina (L., 1758) In Tuz Lake, Yasemi̇n Başbuğ

Turkish Journal of Zoology

In this study, the periodic changes in density and population structure, the generation number, reproduction characteristic and reproduction period of Artemia salina (L., 1758) living in Tuz Lake in 1995 have been investigated. Some physical parameters of lake water at the certain stations have been determined. It has been observed that A. salina is distributed near the coastline of 10 kilometers between the stations Devekonağı and Çalören in the east side of Tuz Lake. Its reproduction period was between April-July and A. salina population consisted two generation in 1995. It has been detected that A. salina population in Tuz Lake …


Mafic Microgranular Enclaves In The Kozak Granodiorite, Western Anatolia, Cüneyt Akal, Cahi̇t Helvaci Jan 1999

Mafic Microgranular Enclaves In The Kozak Granodiorite, Western Anatolia, Cüneyt Akal, Cahi̇t Helvaci

Turkish Journal of Earth Sciences

Enclaves which are relicts of initial basic magma give important information on the origin and evolution of granitic magmas. The mafic microgranular enclaves from the l-type Kozak pluton are less than 1 m that are located at the margin of pluton and mostly less than 15 cm and are generally in sharp contact with the surrounding granodiorite. In some cases, several enclaves may occur close to each other, but they are not closely clustered to form swarms. Most of the enclaves are ellipsoidal in shape. The largest enclaves are less ellipsoidal with curved boundaries. The mafic microgranular enclaves contain same …


Rock-Forming Nannofossils In Uppermost Jurassic-Lowercretaceous Rock Units Of Northwest Anatolia: Nannoconusand Its Resived Taxonomy, Sevi̇nç Özkan Altiner Jan 1999

Rock-Forming Nannofossils In Uppermost Jurassic-Lowercretaceous Rock Units Of Northwest Anatolia: Nannoconusand Its Resived Taxonomy, Sevi̇nç Özkan Altiner

Turkish Journal of Earth Sciences

Nannoconids have been recorded in a rock-forming quantity in the uppermost Jurassic-Lower Cretaceous rock units in Northwest Anatolia, Turkey. Samples were collected from seventeen stratigraphic sections spanning the calciturbidities of the Yosunlukbayiri Formation and pelagic micrites of the Sogukçam Limestone. Because of rareness and difficulties for extracting of calcareous nannofossil species particularly zone markers in these type lithologies, nannoconids have particular attention in terms of biostratigraphy. Twenty nine species of nannoconids were recorded in the studied samples. Their taxonomy were revised and their stratigraphic ranges were given. The classification of genus Nannoconusis based on the gross morphology of the test, …


Geology Of The Dereiçi (Şavsat, Artvin) Cu-Pb-Zn Deposits, Mesut Soylu, Ayhan Erler Jan 1999

Geology Of The Dereiçi (Şavsat, Artvin) Cu-Pb-Zn Deposits, Mesut Soylu, Ayhan Erler

Turkish Journal of Earth Sciences

The geological relationships between the rock units in the Dereiçi/Şavsat (Artvin) region and vein-type Cu-Pb-Zn deposits were presented in this paper. The study area comprises the Upper Cretaceous intermediate volcanic rocks and sedimentary rocks, with Post-Eocene dykes of andesitic and diabasic composition. The mineral deposits are classified as (1) Sphalerite-Galena-Chalcopyrite-Pyrite veins (Talatin Madeni, Binektasi and Fikrinin Madeni), (2) milky quartz-Chalcopyrite-Sphalerite-Galena-Pyrite veins and (3) Chalcopyrite-Pyrite veins. The general paragenetic sequence of the mineralizations is observed as quartz I-pyrite-chalcopyrite-sphalerite-galena-quartz II-chalcocite-covellite. The wall rocks are subjected to silicification, sericitic alteration, chloritization and carbonatization.


Along-Strike Discontinuity Of Active Normal Faults And Its Influence On Quaternary Travertine Deposition; Examples From Western Turkey, Zi̇yadi̇n Çakir Jan 1999

Along-Strike Discontinuity Of Active Normal Faults And Its Influence On Quaternary Travertine Deposition; Examples From Western Turkey, Zi̇yadi̇n Çakir

Turkish Journal of Earth Sciences

Detail mapping of active fault zones bounding four travertine masses in the Gediz and Menderes grabens of western Turkey revealed that they are divided into geometric fault segments up to 13 km long. Fissures, supplying the carbonate-rich waters that give rise to the travertines are preferentially developed at the ends of the fault segments or in extensional step-over zones where the offset between the fault strands is about 1 km or more. The deposition of travertines in such structural settings is probably a consequence of the network of fissures supplying the carbonate-rich waters being highly interconnected where extensional strains were …


Cover And Contents Jan 1999

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.


Cover And Contents Jan 1999

Cover And Contents

Turkish Journal of Biology

No abstract provided.


Cover And Contents Jan 1999

Cover And Contents

Turkish Journal of Biology

No abstract provided.


Cover And Contents Jan 1999

Cover And Contents

Turkish Journal of Biology

No abstract provided.


Cover And Contents Jan 1999

Cover And Contents

Turkish Journal of Biology

No abstract provided.


The Extended Hybrid Model For Optical Phonon Confinement, C. R. Bennett, B. K. Ridley, N. A. Zakhleniuk, M. Babiker Jan 1999

The Extended Hybrid Model For Optical Phonon Confinement, C. R. Bennett, B. K. Ridley, N. A. Zakhleniuk, M. Babiker

Turkish Journal of Physics

The theory of optical phonons and their confinement in heterostructures is reviewed with analogies made to the theory of acoustic phonons. The dielectric continuum (DC) model is obtained when bulk dispersion is ignored and the hybrid model is found when dispersion is included. The issue of boundary conditions is investigated and the solutions are shown with comparisons made using electron-phonon scattering.


Cover And Contents Jan 1999

Cover And Contents

Turkish Journal of Earth Sciences

No abstract provided.