Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Kaygusuz, Abdullah(35)
- Sipahi, Ferkan(35)
- Karsli, Orhan(34)
- Dokuz, Abdurrahman(30)
- Duran, Celal(30)
- Kandemir, Raif(29)
- Ozdes, Duygu(28)
- Maden, Nafiz(27)
- Uzun, Sevda(27)
- Merdan, Mehmet(26)
- Vural, Alaaddin(26)
- Öztürk, Serkan(25)
- Araz, Onur(24)
- Kulakaç, Nurşen(24)
- Ashyralyyev, Charyyar(23)
- Yildiz, Salih(23)
- Yilmaz, Ozgur(23)
- Doğan, Kadir Caner(21)
- Arslan, Mehmet(20)
- Aydin, Faruk(20)
- Doğru, Bülent(20)
- Bayraktar, Alemdar(19)
- Kankal, Murat(19)
- Ayaydin, Hasan(18)
- Baltaci, Cemalettin(18)
- Yolcu, Halil(18)
- Cakir, Tufan(17)
- Cengiz, Ekrem(17)
- Demir, Selim(17)
- Gücer, Mehmet Ali(17)
- Akaryali, Enver(16)
- Artan, Seyfettin(16)
- Hayaloğlu, Pınar(16)
- Kaya, Afşin Ahmet(16)
- Tosunoğlu, Büşra(16)
- Uysal, Ibrahim(16)
- Kurt, Kemal(15)
- Ozturk, Samet(15)
- Reis, Hatice Catal(15)
- Aksakal, Vecihi(14)
Yayınlar
- MakaleYalnız künye2009Frequency optimization of laminated skew plates
Topal, U.; Uzman, Ü.
In this study, the frequency optimization of laminated skew plates is investigated. The objective function is to maximize the fundamental frequency of the laminated skew plates and the fiber orientation is considered as design variable. The mathematical formulation is based on the first-order shear deformation theory (FSDT) for the frequency analysis of the laminated skew plates. The modified feasible direction (MFD) method is combined with the finite element solution of laminated skew plates for optimal designs. Therefore, a program based on FORTRAN is used. Finally, the effect of skew angles, boundary conditions, aspect ratios and functionally graded materials on the optimal results is investigated and the results are compared.
- MakaleYalnız künye2009Chemical contents of red clover genotypes on crop improvement systems as livestock feed
Yolcu, Halil; Tavlas, Ayten; Tan, Mustafa; Gunes, Adem
A field experiment was conducted in 2000-2001 at the Research Station of East Anatolia Agricultural Research Institute in Pasinler of Erzurum province in Turkey. In this study, 25 red clovers (Trifolium pratense L.) genotypes were evaluated in terms of chemical contents for animal feeding in the 2 years results. The red clover genotypes were sown in the spring of 2000. The experiment was designed a randomized complete block with replicated 4 times. The genotypes were harvested in 50% flowering once in 2000 and 3 times in 2001. There were significant differences in N (p<0.05), Mg (p<0.05), Zn (p<0.05), Fe (p<0.05), Mn (p<0.01) and Cu (p<0.01) contents but no in Na content among the red clover genotypes. According to 2 years results, especially L-818 line and Xiashao cultivar in N; L-1881 and L-812 line in Mg; Redwent cultivar, L-77, L-l 922 lines and Lucrun cultivars in Zn; L-77 line, Redwent cultivar, L-812, L-1922 lines and Lucrun cultivar in Fe; L-79 line, Redwent cultivar and L-77 line in Mn; L-79 line, Redwent cultivar and L-77 line in Cu had higher chemical contents than the others for animal feeding. The genotypes rich in terms of chemical content can be successfully used to meet the requirement the forage quality of animal and to gain new quality red clover genotypes for animal nutrition.
- MakaleYalnız künye2009Effects of nitrogen and phosphorus fertilization and seeding patterns on chemical composition of Lucerne and smooth brome grass intercropping system
Yolcu, Halil; Serin, Yunus
Intercropping has been used widely in forage plant production all around the world. In intercropping systems, forage plants need different requirements are grown together. Requirement of fertilization and seeding pattern of intercropping differ from mono cropping. The research goals were to evaluate the effects of various seeding patterns and fertilization on the crude protein and chemical content of lucerne-smooth brome grass mixture under field conditions in 2002-2003. Lucerne and smooth bromegrass mixtures were established with different seeding patterns (mixed, alternative and cross-seeding), N fertilizer rates (0, 60 and 120 kg N ha-1) and P fertilizer rates (0, 40, 80 and 120 P2O5 ha-1). The results of this study indicated that different seeding patterns, N and P fertilization affected chemical contents of alfalfa and smooth brome grass mixture in the intercropping system. Depending on different seeding patterns, N, Ca, K and Mg content varied significantly, but no P content in the intercropping system. Nitrogen application increased N content and P application likewise increased P content. While P application increased N content, N application had no effect on the P content of the intercropping. Calcium and K did not vary significantly depending on N and P fertilization; yet, a relationship between P application and Mg content was determined.
- MakaleYalnız künye2009Morphologic, yield and quality parameters of some annual forages as sole crops and intercropping mixtures in dry conditions for livestock
Yolcu, Halil; Polat, Muazzez; Aksakal, Vecihi
Sole annual legumes, cereals and intercropping mixture of annual legumes and cereals are intensively cultivated in the world for forage production. An experiment was carried out to compare morphological, yield and quality parameters of sole Hungarian vetch (Vicia pannonica Crantz.), sole oat (Avena sativa L.), sole rye (Secale cereale L.), Hungarian vetch (Vicia pannonica Crantz.) + oat (Avena sativa L.), Hungarian vetch (Vicia pannonica Crantz.) + rye (Secale cereale L.), Hungarian vetch (Vicia pannonica Crantz.) + barley (Hordeum vulgare L.) and Hungarian vetch (Vicia pannonica Crantz.) + wheat (Triticum aestivum L.) intercropping mixture in Kelkit Aydin Doǧan Vocational Training School at Gümüşhane University of Turkey in dry and manure conditions during 2006-2007 and 2007-2008 years. Sole rye and Hungarian vetch + rye intercropping mixture had the highest stem density. The highest cereal flag leaf lengths were in wheat in intercropping mixture, sole oat and oat in intercropping mixture. Rye in intercropping mixture and sole rye had the highest cereal length. The highest legume ratio was found in Hungarian vetch + oat intercropping mixture. Sole rye and Hungarian vetch + rye intercropping mixture had the highest fresh and hay yield. The highest crude protein yield was obtained in Hungarian vetch + oat intercropping mixture. Sole Hungarian vetch and Hungarian vetch + barley intercropping mixture had the highest crude protein content. The lowest acid detergent fiber (ADF) and neutral detergent fiber (NDF) contents were gained in sole Hungarian vetch. Farmers in terms of yield may choose cultivation of sole rye and Hungarian vetch + rye intercropping mixture. Also in terms of quality, they may choose cultivation of sole Hungarian vetch and Hungarian vetch + oat intercropping mixture in dry and manure conditions.
- MakaleYalnız künye2009Estimates of genetic and phenotypic parameters for the birth weight of calves of Holstein Friesian cattle reared organically
Aksakal, Vecihi; Bayram, Bahri
The aim of this study, was to estimate genetic and phenotypic parameters for birth weight and to determine the survival rate of calves of Holstein Friesian cattle reared organically. Aborting rate, still born rate and the calving difficulty rate were 4.6, 3.9 and 9.1 %, respectively. The average birth weight was 42.76±0.229 kg in present study. This value was quite higher than the birth weight in Holstein Friesian calves that breed conventionally in Turkey's conditions. The effect of calving season (p<0.01) and farming system (p<0.05) on birth weight were significant. Male calves had 2.69 kg higher birth weight than females and this difference was found significant (p<0.01). The mean birth weight of single calves was 6.26 kg (17%) higher than that of twin calves. The effect of the years on birth weight was not significant, because caring, feeding and the other breeding methods were made according to the conditions of the regulations. As the birth parity was increased, the birth weight decreased (p<0.05). Heritability and repeatability estimates belong to birth weight were found as 0.232±0.110 and0.206±0.073, respectively.
- MakaleYalnız künye2009K/Ar ages and geochemistry of the post-collisional volcanic rocks in the Mica (Erzurum) area, eastern Turkey
Kaygusuz, Abdullah
The Neogene Ilica volcanics in eastern Anatolia are of sub-alkaline affinity and present features of post-collisional volcanism. The lava flows in the Ilica area reveal K/Ar ages ranging from 13.9 ± 0.5 to 4.4 ± 0.3 Ma, corresponding to the Miocene- and Pliocene age. The volcanic rocks are composed of calc-alkaline basaltic trachyandesitic-, trachyandesitic-, andesitic- and minor dacitic lavas associated with pyroclastics, with the andesitic lavas being volumetrically the most abundant. Some special textures, such as the dissolution/melting and poikilitic type, and the normal, reverse, and oscillatory zoning in the plagioclase- and pyroxene phenocrysts are attributable to disequilibrium crystallization related to magma mixing. The rocks are characterized by enrichment in large ion lithophile elements (LILE) and light rare earth elements (LREE), with pronounced depletion of high field strength elements (HFSE). They show depletion in Nb and Ta, indicating the role of crustal contamination. The rocks also have moderately fractionated rare earth elements (REE) patterns with (La/Lu)N ratios of 10-19 for andesitic- and dacitic rocks, and 7-10 for basaltic trachyandesitic- and trachyandesitic rocks. Basaltic trachyandesites show slightly positive Eu anomalies, whereas the deepening of Eu through gradual increase from trachyandesite to dacite, indicating a genetic link between the basaltic trachyandesite and the dacites. The main solidification processes consist of magma mixing and fractional crystallization with minor amounts of crustal contamination which were operative during the solidification of the volcanic rocks. All evidences support the theory that Ilica volcanic rocks were derived from partial melting of lower continental crust, having undergone interaction with subcontinental lithospheric mantle in a post-collisional geodynamic setting.
- MakaleYalnız künye2009Effects of various ages of weaning on growth characteristics, survival rate and some body measurements of Awassi lambs
Aksakal, Vecihi; Macit, Muhlis; Esenbuga, Nurinisa
This study aimed to investigate the effect of various ag es (45, 60 and 7 5 days) of weaning on growth, survival rate and some body characteristics in Awassi lambs. Following weaning, the lambs were separated from their dams and taken to the pasture and were fed with concentrate including 15.3% crude protein in the evenings in addition to the pasture. The live weights and daily weight gains of the lambs were determined by weighing at 14 days intervals starting from day 45 till the end of pasture. Five females from each group were used in the determination of body measurements. In the study, in the lambs weaned at the age of 45 (group I), 60 (group JT) and 75 (group III) days old; birth weight and live weights on days 45, 60, 75, 120 and 210 (end of pasture) were calculated on average as 4.58,11.58, 13.95, 15.95, 21.54 and 34.44 kg, respectively and in the significance checks performed, it was identified that there was no significant (p<0.05) difference between the groups except for the day 210 live weight. There was not any difference observed between the groups in terms of Daily Live Weight Gain (DLWG). It was identified that the effect of the age of dam on live weight in lambs was insignificant in all periods that the effect of type of birth was very significant (p<0.05) except for the day 120 live weight and that the effect of sex was significant (p<0.05) in birth, day 60, 75 and 210 weights and very significant (p<0.01) in day 120 live weight. On looking at the survival rate characteristics, it was observed that this was lower in the group weaned at 45 days old on days 120 and 210 at a statistically significant (p<0.05) level compared to the other two groups. Furthermore, it was identified that singletons exhibited a higher survival rate at a statistically very significant (p<0.01) level compared to twins. The effect of weaning at various ages on the body measurements was found to be insignificant except for the chest width measured on day 210. Consequently, it may be said that taking into consideration the live weight gains and survival rate characteristics of Awassi lambs, the most suitable weaning age may be arranged as 60 days old.
- MakaleYalnız künye2009Evaluation of annual legumes and barley as sole crops and intercrop in spring frost conditions for animal feeding II. Mineral composition
Yolcu, Halil; Gunes, Adem; Turan, Metin
Sole grass pea (Lathyrus sativus L.), sole common vetch (Vicia sativa L.), sole barley (Hordeum vulgare L.), common vetch + barley intercrop, common vetch (I) and barley (I) in terms of mineral contents were assessed in the present study for animal feeding. Common vetch + barley intercrops were separated as common vetch (called as common vetch I) and barley (called as barley I). The experiment was designed in a factorial arrangement of a randomized complete block design with 3 replications and carried out at the research station at Kelkit Aydin Dogan Vocational Training School, Gumushane University, in 2006 and 2007. All the plants had important potential in terms macro and micro mineral contents in animal feeding. There were significant differences between years in Mg, Ca, P, Mn, Fe and Cu contents. According to the results, sole grass pea, sole common vetch and common vetch (I) in Mg, sole grass pea, common vetch (I) and sole common vetch in Ca, common vetch (I), sole grass pea and sole common vetch in Mn and sole barley and sole grass pea in Cu were rich for animal feeding. If farmers want rich forage in terms of Mg, Ca and Mn, they should select sole grass pea and sole common vetch cultivation. If farmers want rich forage in terms of Cu, they should choose sole grass pea and sole barley cultivation.
- MakaleYalnız künye2009Stochastic finite element analysis of structural systems with partially restrained connections subjected to seismic loads
Çavdar, Özlem; Bayraktar, Alemdar; Çavdar, Ahmet; Kartal, Murat Emre
The present paper investigates the stochastic seismic responses of steel structure systems with Partially Restrained (PR) connections by using Perturbation based Stochastic Finite Element (PSFEM) method. A stiffness matrix formulation of steel systems with PR connections and PSFEM and MCS formulations of structural systems are given. Based on the formulations, a computer program in FORTRAN language has been developed, and stochastic seismic analyses of steel frame and bridge systems have been performed for different types of connections. The connection parameters, material and geometrical properties are assumed to be random variables in the analyses. The Kocaeli earthquake occurred in 1999 is considered as a ground motion. The connection parameters, material and geometrical properties are considered to be random variables. The efficiency and accuracy of the proposed SFEM algorithm are validated by comparison with results of Monte Carlo simulation (MCS) method.
- MakaleYalnız künye2009Frequency optimization of laminated general quadrilateral and trapezoidal thin plates
Topal, Umut
This paper deals with frequency optimization of symmetrically laminated angle-ply general quadrilateral and trapezoidal thin plates. The objective function is to maximize the fundamental frequency of the quadrilateral and trapezoidal laminated plates and the fibre orientation is considered as design variable. The mathematical formulation is based on the classical laminated plate theory (CLPT) for the frequency analysis. The modified feasible direction (MFD) method is used as the optimization routine. Therefore, a program based on FORTRAN is used. Finally, the significant effects of aspect ratios, boundary conditions, taper ratios and unsymmetric trapezoidal plates on the optimal results are investigated and the results are compared.
- MakaleYalnız künye2009Determination of tectonic and crustal structure of the eastern pontide orogenic belt (NE Turkey) using gravity and magnetic data
Maden, Nafiz; Gelisli, Kenan; Eyuboglu, Yener; Bektas, Osman
The Eastern Pontide Orogenic Belt is one of the most complex geodynamic settings within the Alpine belt. Subduction polarity, which is responsible for the formation of the Eastern Pontide Magmatic Arc, is still under debate because of limited geological, geophysical and geochemical data. This orogenic belt is mainly divided into three subzones depending on lithological characteristics and facies changes as in Northern, Southern and Axial Zones from North to South. These zones are separated from each other by near-vertical faults that display the block-faulting tectonic style of this belt. In this study, the tectonic and crustal structure of the Eastern Pontides, which as yet have not been prospected by using geophysical data, has been investigated with potential field data. The horizontal gradient map obtained from gravity data shows a number of steep and gentle lineaments. It seems that these lineaments E-W, NE and NW-trending correspond to major structural zones of continental crust. Additionally, The Moho depth and Curie point depth variation maps of the Eastern Pontide Orogenic Belt have been computed with the power spectral method of the radial wavenumber carried out by using the fast Fourier transform method. As a result of this method, we estimated that the depths of the Moho and Curie point varied between 29.0 ± 1.2-47.2 ± 1.9 km and 14.3 ± 0.7-27.9 ± 1.4 km, respectively. Our findings indicate that the Moho depth generally increases from north to south in the region. However, the Curie point depth level within the crust has an undulating surface, not a horizontal one.
- MakaleYalnız künye2009Effects of nonuniform boundary conditions on the buckling load optimization of laminated composite plates
Topal, Umut; Uzman, Ümit
This paper deals with buckling load optimization of symmetrically laminated composite thin plates under the uniaxial and biaxial compressive loads with discontinuities along the boundaries. The objective of the design problem is to maximize the buckling load of the laminated plates and the fibre orientation is taken as design variable. The classical laminate plate theory is used for the mathematical formulations of the laminates. The modified feasible direction method is used as optimization routine. Therefore a program based on FORTRAN is used. Finally, the effect of nonuniform boundary conditions, aspect ratios and load ratios on the optimum results is illustrated.
- MakaleYalnız künye2009Implementation of different encoding types on structural optimization based on adaptive genetic algorithm
Bekiroǧlu, Serkan; Dede, Tayfun; Ayvaz, Yusuf
In this study, the use of new alternatives of encoding types such as quaternary encoding and octal encoding is reviewed along with that of binary and value encodings and how they provide contribution to efficiency and robustness of genetic algorithm is discussed in structural problems. In addition to new alternatives of encoding types, a genetic algorithm with adaptive manner is presented so that an adaptive approach including adaptive mutation and adaptive crossover operators is employed. It is concluded that it is not possible to tell that one of the encoding types is exactly dominant over the others in all aspects such as convergence, finding the optimum solution, and iteration number. However, it is worth to say that to run genetic process with different encoding types should be considered since one of the runs can give more appropriate solution than that of the others.
- MakaleYalnız künye2009Evaluation of annual legumes and barley as sole crops and intercrop in spring frost conditions for animal feeding I. Yield and quality
Yolcu, Halil; Dasci, Mahmut; Tan, Mustafa
This study evaluated sole grass pea (Lathyrussativush.), sole common vetch (Vicia sativa L.), sole barley (Hordeum vulgare L.), common vetch + barley intercrop, common vetch (I) and barley (I) in terms of yields and quality properties in 2006-2007 at Kelkit Aydin Dogan Vocational Training School Research Station of Gumushane University, Turkey. Intercrop plants were separated as common vetch (called as common vetch I) and barley (called as barley I). Plants were seeded in April of both years in a randomized complete block design with 3 replications. The study plots were 3.0 m long by 1.68 m wide, with 24 cm row spacing. Each plot was fertilized with 20 ton ha-1 organic farmyard manure. The year effects were significant in dry matter yield, crude protein, crude protein yield, acid detergent fiber and neutral detergent fiber. The legumes especially were injured by frost in 2007. Significant differences were found in terms of Dry Matter Yield (DMY), Crude Protein (CP), Crude Protein Yield (CPY), Acid Detergent Fiber (ADF), Neutral Detergent Fiber (NDF), Dry Matter Intake (DMI), Dry Digestible Matter (DDM) and Relative Feed Value (RFV) amongst all the plants. Sole common vetch and sole barley had good properties in DMY, CP and CPY. Sole grass pea, common vetch (I), sole common vetch and intercrops showed good quality properties in ADF and NDF. Sole grass pea especially, sole common vetch and common vetch (I) had good quality properties in DMI, DDM and RFV. Farmers should prefer sole common vetch and sole grass pea cultivation in yield and quality and regulate their seeding times according to days with frost in similiar conditions.
- MakaleYalnız künye2009Lithostratigraphy, facies, and deposition environment of the lower Jurassic Ammonitico Rosso type sediments (ARTS) in the Gümüşhane area, NE Turkey: Implications for the opening of the northern branch of the Neo-Tethys Ocean
Kandemir, Raif; Yilmaz, Cemil
Ammonitico Rosso type sediments (ARTS) form the bottom level of the Şenköy Formation in the Gümüşhane area. The formation accumulated in the rift-related basins triggered by extensional tectonic regimes in the Early Jurassic times. Six different sections were studied in this area in order to interpret the lithostratigraphy, facies, and deposition environments of the ARTS. Two basic lithofacies were distinguished, nodular-marly and nodular-calcareous. These facies provide useful information regarding depositional conditions in the area and environmental energy. These factors were mainly related to the relative sea-level that in turn was controlled by tectonic and eustasy conditions. In addition, seven different types of microfacies were recognized and described as a result of the detailed analysis of the sections. The results of the analysis show that these sediments in the Gümüşhane area were developed in transgressive phases/events. These sediments share characteristics with other peri-Mediterranean regions and sea-level curves, and show a similarity to the major transgressive pulse during the Pliensbachian stage. Deposition of ARTS was controlled by syn-depositional extensional movements, leading to their accumulation on top of tilted blocks, slopes and horsts in an open marine environment. The ARTS were developed during the rifting of the continental margins pointing up the phases of the Tethys opening. Neptunian dykes verifying this opening developed at different levels of the ARTS and were filled with overlying sediments. These results support the hypothesis that the ARTS were formed in tectonically active environments where extensional tectonic movements were continuously improved during the deposition of the ARTS.
- MakaleYalnız künye2009Thermal buckling load optimization of laminated skew plates
Topal, U.; Uzman, Ü.
In this study thermal buckling load optimization of laminated skew plates subjected to uniformly distributed temperature load is investigated. All of the laminates considered are assumed to have fully clamped boundary conditions, though the general boundary conditions may also be studied without any difficulty. The objective function is to maximize the critical temperature capacity of the laminated skew plates and the fibre orientation is considered as design variable. The first-order shear deformation theory is used in the mathematical formulation. Nine-node Lagrangian rectangular plate element is used for the finite element solution of the skew laminates. The temperature field is assumed to be uniform over the plate surface and varies in the thickness direction only. Modified feasible direction method (MFD) is used for the optimization routine. A program based on FORTRAN is used for the optimization problem. Finally, the effect of number of layers, skew angles, aspect ratios, width-to-thickness ratios and antisymmetric lay-up on the optimal designs is investigated and the results are compared.
- MakaleYalnız künye2009Frequency optimization of laminated folded composite plates
Topal, U.; Uzman, Ü.
In this study, frequency optimization of symmetrically laminated folded composite plates is presented. The folded plates are modelled as a composite structure that consists of flat plates. The fundamental frequencies of one- and two-fold folded plates are maximized with respect to fibre orientations. The first-order shear deformation theory (FSDT) is used for vibration analysis of laminated folded plates. The modified feasible direction (MFD) method is used for the optimization routine. Therefore a program based on FORTRAN is used. Finally, the significant effects of length-to-thickness ratios, crank angles, different plate lengths and boundary conditions on the optimum results are demonstrated.
- MakaleYalnız künye2009Mineralogy, whole-rock and Sr-Nd isotope geochemistry of mafic microgranular enclaves in Cretaceous Dagbasi granitoids, Eastern Pontides, NE Turkey: Evidence of magma mixing, mingling and chemical equilibration
Kaygusuz, Abdullah; Aydinçakir, Emre
Rocks of the Late Cretaceous Dagbasi Pluton (88-83 Ma), located in the eastern Pontides, include mafic microgranular enclaves (MMEs) ranging from a few centimetres to metres in size, and from ellipsoidal to ovoid in shape. The MMEs are composed of gabbroic diorite, diorite and tonalite, whereas the felsic host rocks comprise mainly tonalite, granodiorite and monzogranite based on both mineralogical and chemical compositions. MMEs are characterized by a fine-grained, equigranular and hypidiomorphic texture. The common texture of felsic host rocks is equigranular and also reveals some special types of microscopic textures, e.g., oscillatory-zoned plagioclase, poikilitic K-feldspar, small lath-shaped plagioclase in large plagioclase, blade-shaped biotite, acicular apatite, spike zones in plagioclase and spongy-cellular plagioclase textures and rounded plagioclase megacrysts in MMEs. Compositions of plagioclases (An33-An60), hornblendes (Mg#=0.77-1.0) and biotites (Mg#=0.61-0.63) of MMEs are slightly distinct or similar to those of host rocks (An12-57; hbl Mg#=0.63-1.0; Bi Mg#=0.50-0.69), which suggest partial to complete equilibration during mafic-felsic magma interactions. The felsic host rocks have SiO2 between 60 and 76 wt% and display low to slightly medium-K tholeiitic to calc-alkaline and peraluminous to slightly metaluminous characteristics. Chondrite-normalized rare-earth element (REE) patterns are fractionated (Lacn/Lucn=1.5-7.3) with pronounced negative Eu anomalies (Eu/Eu*=0.46-1.1). Initial εNd(i) values vary between -3.1 and 1.6, initial 87Sr/86Sr values between 0.7056 and 0.7067. Compared with the host rocks, the MMEs are characterized by relatively high Mg-number of 22-52, low contents of SiO2 (53-63 wt%), low ASI (0.7-1.1) and low to medium-K tholeiitic to calc-alkaline, metaluminous to peraluminous composition. Chondrite-normalized REE patterns are relatively flat [(La/Yb)cn=1.4-3.9; (Tb/Yb)cn=0.9-1.5] and show small negative Eu anomalies (Eu/Eu*=0.63-1.01). Isotope signatures of these rocks (87Sr/86Sr(i)=0.7054-0.7055; εNd(i)=-1.0 to 1.9) are largely similar to the host rocks. Gabbroic diorite enclaves have relatively low contents of SiO2, ASI; high Mg#, CaO, Al2O3, TiO2, P2O5, Sr and Nb concentrations compared to dioritic and tonalitic enclaves. The geochemical and isotopic similarities between the MMEs and their host rocks indicate that the enclaves are of mixed origin and are most probably formed by the interaction between the lower crust- and mantle-derived magmas. All the geochemical data suggest that a basic magma derived from an enriched subcontinental lithospheric mantle, interacted with a crustal melt that originated from dehydration melting of the mafic lower crust at deep crustal levels. The existence of compositional and textural disequilibrium and the nature of chemical and isotopic variation in these rock types indicate that magma mixing/mingling between an evolved mafic and a granitic magma was involved in their genesis. Microgranular enclaves are thus interpreted to be globules of a more mafic magma probably from an enriched lithospheric mantle source. Al-in-amphibole estimates the pluton emplacement at ca. 0.3-3.8 kbar, and therefore, magma mixing and mingling must have occurred at 3.8 kbar or below this level.
- MakaleYalnız künye2008Elazığ çevresindeki kayaçların beton agregası olarak kullanılabilirliği
Gurocak, Zulfu; Alemdag, Selcuk
Bu çalışmada, Elazığ çevresinde yüzeyleyen kayaçların beton agregası olarak kullanılabilirliğinin belirlenmesi amaçlanmıştır. Bu amaç doğrultusunda, Keban Uetamorfitleri, Elazığ Magmatitleri, Harami Formasyonu, Maden Karmaşığı, Kırkgeçit Formasyonu ve Karabakır Formasyonu' ndan farklı noktalardan kaya örnekleri alınmış, kaya ve agrega örneklerinde deneysel çalışmalar yapılmıştır. Petrografik ve kimyasal özellikleri belirlemek için, kimyasal analizler ve ince kesitlerde petrografik çalışmalar yapılmıştır. Ayrıca, kaya örneklerinin birim hacim ağırlık, ağırlıkça ve hacimce su emme, porozite, doluluk oranı, serbest basınç dayanımı belirlenmiştir. Çeneli kırıcı yardımıyla standart boyutta agrega örnekleri hazırlanmış, bu agregaların alkali agrega reaktivitesi, magnezyum sülfat çözeltisinde don kaybı, özgül ağırlık, su emme, yıkanabilir madde içeriği ve Los Angeles aşınma dayanımı belirlenmiştir. Deney sonuçları TSE standartlarındaki sınır değerler ile karşılaştırılmıştır. Keban Metamorfitleri, Elazığ Magmatitleri ve Kırkgeçit Formasyonu' nun düşük Los Angeles aşınma direncine ve özgül ağırlığa sahip olması nedeniyle, bu kayaçların beton agregası olarak kullanılması uygun değildir. Maden Karmaşığı ve Karabakır Formasyonu'na ait bazaltların tüm fiziko-mekanik özellikleri beton agregası olarak kullanılabilme açısından uygundur ve bu kay açlar beton agregası olarak kullanılabilirler.
- MakaleYalnız künye2008Atatürk Üniversitesi Ziraat Fakültesi Çiftliğinde yetiştirilen siyah alaca sığırlarda akrabalı yetiştirme düzeyi ile bunun bazı üreme ve süt verim özellikleri üzerine etkileri
Bilgin, Ömer C.; Yanar, Mete; Tüzemen, Naci; Güler, Olcay; Aydin, Recep; Akbulut, Omer; Bayram, Bahri
Bu çalışmada, Atatürk Üniversitesi Ziraat Fakültesi Çiftliğinde 1989-2002 yılları arasında yetiştirilen Siyah Alaca sığırlarda akrabalı yetiştirme katsayıları hesaplanmış ve yıllar itibarıyla akrabalı yetiştirme düzeyindeki değişimler incelenmiştir. Ayrıca akrabalı yetiştirme düzeyinin doğum ağırlığı ve ilkine buzağılama yaşı gibi üreme özellikleri ve süt verim özellikleri üzerine etkileri de araştırılmıştır. İncelenen dönemde, doğan Siyah Alaca sığırların ortalama akrabalı yetiştirme katsayısı % 1.35 ± 0.45 olarak saptanmıştır. Yıllara göre akrabalı yetiştirme düzeyi dalgalanmalar göstermiştir. 1995 hariç, 1989–1996 yılları arasında akrabalı yetiştirme söz konusu değildir. Son yıllarda ise, akrabalı yetiştirme katsayısında bir artış saptanmıştır. Akrabalı yetiştirme düzeyinin doğum ağırlığını önemli (P<0.01) seviyede etkilediği saptanmıştır. Akrabalı yetiştirme katsayısındaki her % 1’lik artışa karşılık, doğum ağırlığında 0.264 ± 0.006 kg’lık azalma olmuştur. Akrabalı yetiştirilen Siyah Alaca sığırların ilk laktasyon 305 gün süt (P<0.01), günlük süt (P<0.01) ve laktasyon yağ verimi (P<0.05), akrabalı yetiştirilmeyenlere göre önemli derecede düşük belirlenmiştir. Bununla birlikte, ilkine buzağılama yaşı, % süt yağı oranı ve laktasyon süresi gibi diğer özellikler akrabalı yetiştirmeden etkilenmemiştir.