Yayınlar
Koleksiyondaki öğeler
- MakaleYalnız künye2008Scopus SJRQ1Investigation of seismic behavior of fluid-rectangular tank-soil/foundation systems in frequency domain
Livaoglu, R.
Main purpose of this study is to evaluate the dynamic behavior of fluid-rectangular tank-soil/foundation system with a simple and fast seismic analysis procedure. In this procedure, interaction effects are presented by Housner's two mass approximations for fluid and the cone model for soil/foundation system. This approach can determine; displacement at the height of the impulsive mass, the sloshing displacement and base forces for the soil/foundation system conditions including embedment and incompressible soil cases. Models and equations for proposed method were briefly explained for different tank-soil/foundation system combinations. By means of changing soil/foundation conditions, some comparisons are made on base forces and sloshing responses for the cases of embedment and no embedment. The results showed that the displacements and base shear forces generally decreased, with decreasing soil stiffness. However, embedment, wall flexibility, and soil-structure interaction (SSI) did not considerably affect the sloshing displacement.
AtıfScopus78OpenAlex75
İncele - MakaleYalnız künye2008Scopus SJRQ4Mineralogy, mineral chemistry, and fluid inclusion investigation of Köstere hydrothermal vein-type deposit (Gümüşhane, NE-Turkey)
Demir, Yilmaz; Uysal, Ibrahim; Sadiklar, M. Burhan; Sipahi, Ferkan
Vein type Köstere ores were deposited along cracks formed as a result of NE-SW fault system in the late Cretaceous felsic volcanic rocks in the northeastern Black Sea Region of Turkey. Total silver content of the Köstere ore is controlled by total silver content of the hydrothermal solution, homogenization temperature of the ore minerals and modal abundances of the tetrahedrite-tennantite serie minerals. The Zn/Cd ratios of sphalerites from the Köstere deposit are close to those of granite-related classical vein-type hydrothermal deposits. Furthermore Co/Ni ratio in pyrite separates, higher than unit, suggests an acidic source for the ore forming fluids. Homogenization temperatures of 200-370 °C and salinity of 0-9.85 eq. wt% NaCl were obtained on the basis of fluid inclusions studies measured in quartz minerals. These data indicate that ore formation conditions for the Köstere ore are similar with the vein-type epithermal-mesothermal deposits, related to the magmatic fluids. The overall low salinities of fluids (on average: 5.4 eq. wt% NaCl) suggest that meteoric waters were involved in mineralization. The possibility of interactions between ascending hydrothermal fluids and dilute meteoric waters is supported by geological features and mineralogical data which indicate a shallow depth of mineralization. Torul Pluton, which is the younger acidic unit (72 my) in the area, is suggested to be related to the formation of Köstere deposit.
AtıfScopus17OpenAlex17İncele - MakaleYalnız künye2009Scopus SJRQ1Thermal buckling load optimization of angle-ply laminated cylindrical shells
Topal, U.; Uzman, Ü.
In this study, thermal buckling load optimization of symmetrically laminated cylindrical shells subjected to uniformly distributed temperature load is investigated. The objective function is to maximize the critical temperature capacity of laminated shells and the fibre orientation is considered as design variable. The first-order shear deformation theory is used to study thermal buckling response of the laminates. The modified feasible direction method is used as optimization routine. For this purpose, a program based on FORTRAN is used for the optimization of shells. Finally, the effects of number of layers, length-to-radius ratio and boundary conditions on the optimum results are investigated.
AtıfScopus20OpenAlex16İncele - MakaleYalnız künye2002Scopus SJRQ2Geothermal energy: Power for a sustainable future
Kaygusuz, Kamil; Kaygusuz, Abdullah
This paper discusses the potential and utilization of geothermal energy in Turkey. Geothermal energy for electricity generation has been produced commercially since 1913, and for 4 decades on the scale of hundreds of MW both for electricity generation and direct use. Utilization has increased rapidly during the last 3 decades. In 2000, geothermal resources were identified in over 80 countries, and there are quantified records of geothermal utilization in 58 countries in the world. The worldwide use of geothermal energy amounts to 49 TWh/y of electricity and 53 TWh/y for direct use. On the other hand, Turkey is one of the countries with significant potential in geothermal energy. Resource assessments have been made many times by the Mineral Research and Exploration Directorate (MTA) of Turkey. The main uses of geothermal energy are mostly moderate and low temperature applications such as space heating and domestic hot water supply, greenhouse heating, industrial processes, heat pumps, and electricity generation. The data accumulated since 1962 show that the estimated geothermal power and direct use potential are about 4500 MWe and 31500 MWt, respectively. Present applications have shown that geothermal energy in Turkey and other countries is clean and much cheaper compared to the other fossil and renewable energy sources.
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İncele - MakaleYalnız künye2008Scopus SJRQ1Investigation of dynamic response of masonry minaret structures
Dogangun, Adem; Acar, Ramazan; Sezen, Halil; Livaoglu, Ramazan
Almost all historical minarets in Turkey were constructed using cut stone, masonry blocks or combination of these two materials. The structural and geometrical properties of each masonry minaret, or slender tower structure, depend on many factors including the structural knowledge and applications at the time of construction, experience of the architect or engineer, seismicity of the region, and availability of construction materials in that area. Recent earthquakes in Turkey have shown that most masonry minarets in high seismic regions are vulnerable to structural damage and collapse. In this study, in order to investigate the dynamic behavior of historical unreinforced masonry minarets, three representative minarets with 20, 25, and 30 m height were modeled and analyzed using two ground motions recorded during the 1999 Kocaeli and Duzce, Turkey earthquakes. The modal analyses of the models have shown that the structural periods and the overall structural response are influenced by the minaret height and spectral characteristics of the input motion. The dynamic displacement and axial stress time histories are computed at the critical points on the minarets. During recent earthquakes, most minaret failures occurred above the base of the structure. Consistent with the observed response, the largest stresses were calculated at the same location.
AtıfScopus122OpenAlex133İncele - MakaleYalnız künye2004Scopus SJRQ1Energy and sustainable development. Part II: Environmental impacts of energy use
Kaygusuz, Kamil; Kaygusuz, Abdullah
As a consequence of the fast-growing energy requirements and the increasing use of low-grade domestic fuels, air pollution has increased considerably in recent years in Turkey. Since the energy demand is projected to continue to increase rapidly in the future also, energy-supply strategies are required to control air-pollutant emissions in a cost-efficient way, taking into account the legal emission-control regulations that have been enforced. This article extensively concentrates on energy and environmental impacts in Turkey only. Energy utilization and its major environmental impacts are discussed from the standpoint of sustainable development, including anticipated patterns of future energy use and subsequent environmental issues. Several aspects relating to energy utilization, renewable energy, energy efficiency, environment, and sustainable development are examined from both current and future perspectives in the country. In this study, air-pollutant emissions due to power generation and their harmful effects on the environment are also estimated.
AtıfScopus15WoS11OpenAlex16İncele - MakaleYalnız künye2009Scopus SJRQ1C2/c pyroxene phenocrysts from three potassic series in the Neogene alkaline volcanics, NE Turkey: Their crystal chemistry with petrogenetic significance as an indicator of P -T conditions
Aydin, Faruk; Thompson, Richard M.; Karsli, Orhan; Uchida, Hinako; Burt, Jason B.; Downs, Robert T.
Chemical and structural data are reported for C2/c pyroxene phenocrysts collected from three potassic series (Group A: basanite-tephrite, Group B: tephrite-phonolitic tephrite, Group C: alkaline basalt-trachybasalt) of the Neogene alkaline volcanics (NAVs) in northeastern Turkey, in order to investigate the evolution of the magmatic plumbing system and the location of magma chamber(s) with crystallization conditions. The rock series hosting the clinopyroxene phenocrysts show generally porphyritic texture and have a variable phenocryst-rich nature (20-58%), with phenocryst assemblages characterized by cpx ± ol ± plag ± foid ± amp ± bio. The clinopyroxene phenocrysts can be chemically classified as Ti- and Fe3-rich Al-diopsides for Groups A and B (ABcpxs) and Ti- and Fe3-poor Al-diopsides for Group C (Ccpxs). They have poorly variable composition, clustering in the diopside field. Structurally, the diopside groups have nearly similar a (ranging from 9.73 to 9.75 Å), Vcell (437.2-440.9 Å3), and hbetai angle values (106.01°-106.23°), but some differences in polyhedral parameters and geometries of the AB-cpxs and C-cpxs have been observed. For example, the AB-cpxs are characterized by. larger c (5.27-5.30 vs. 5.25-5.28 Å), VT (2.27-2.30 vs. 2.23-2.28 Å3), and VM2 (25.53-25.72 vs. 25.41-25.59 Å3) values and smaller b (8.87-8.88 vs. 8.88-8.91 Å) and VM1(11.49-1.63 vs. 11.64-11.83 Å3) values with respect to the C-cpxs. In addition, the AB-cpxs show higher values of VM2/VM1 (2.20-2.23) due to large VM2 and small VM1 compared to the VM2/ VM1 ratios of the C-cpxs (<2.19). Such differences in the crystal structure of the AB-cpxs and C-cpxs from the NAVs are partly related to different crystallization pressures, but mostly related to variation in melt composition and, possibly, the influence of other crystallizing mineral phases. In particular, R(M2-O1) and R(M1-O2) (i.e. bond lengths) differences in the clinopyroxenes of different groups support the presence of evolved host rocks with different alkaline character (i.e. silicaundersaturated Groups A-B and silica-saturated Group C). Based on the cpx-geothermobarometry, the crystallization pressures for the C-cpxs are lower than 4.5 kbars, but the AB-cpxs have relatively high-pressure values (5.6- 10.6 kbars), suggesting that the AB-cpxs crystallized in higher pressure environments. The relatively higher crystallization temperatures of the AB-cpxs also indicate higher cooling rates. The P-T estimates suggest that the source regions of the clinopyroxene phenocrysts from the NAVs were crustal magma chambers in a closed plumbing system at a moderate- to low-pressure regime.
AtıfScopus25WoS27OpenAlex28İncele - MakaleYalnız künye2009Scopus SJRQ3The effect of average daily gain and age at first calving on reproductive and milk production traits of brown swiss and holstein friesian cattle
Bayram, B.; Yanar, M.; Akbulut, O.
The purpose of the study was to determine the effects of average daily gain and age at first calving on the reproductive and milk production traits of Brown Swiss (BS) a.d Holstein Friesian (HF) cattle. For this purpose, daily gains and ages at first calving were divided into two groups which were below the average called as the "slow" or "early" groups and above the average named as "moderate" or "late" groups respectively. BS heifers in the moderate group reached the first insemination age and first calving age 103.7 and 101.7 days earlier (P>0.01) than these in the slow group respectively. The corresponding values for HF heifers were 37.8 and 29.5 days respectively and were not significant. While the average daily gain had negative effects on reproduction traits following the first calving, the daily gain of BS had no effect on the milk production traits in all parities. HF heifers in the moderate group had higher (P>0.05) actual (585 kg) and 305 days milk yield (324 kg) in the second parity. Early calving in both breeds resulted in a significant (P>0.05) reduction in the actual and 305-days milk yield in the first parity. Early calving caused a significant decrease (P>0.05) in the actual milk yield, 305-days milk yield, actual milk fat and 305-days milk fat yield of BS cows in the first parity. Either early or late calving in BS didn't affect on milk traits in second and third parities. The early calving in HF lowered significantly (P>0.05) the actual and 305-days milk yield in first lactation. However, late calving in HF resulted in lower actual milk yield, 305-days milk yield, actual milk fat yield and 305-days milk fat yield in third parity.
AtıfScopus15WoS12İncele - MakaleYalnız künye2006Scopus SJRQ1Geochemical constraints on the provenance, mineral sorting and subaerial weathering of Lower Jurassic and Upper Cretaceous clastic rocks of the eastern Pontides, Yusufeli (Artvin), NE Turkey
Dokuz, Abdurrahman; Tanyolu, Erkan
An integrated petrographic and geochemical study of the shales and sandstones of Early Jurassic and Late Cretaceous age in the Yusufeli area (Turkey) was carried out to obtain more information on their provenance, sedimentological history and tectonic setting, as well as to evaluate the influence of weathering, hydraulic sorting and recycling processes upon source-rock signature. Depending on their matrix and mineralogical content the Lower Jurassic sandstones are identified as arkosic arenite and wacke, while the Upper Cretaceous sandstones are defined as lithic arenite and wacke. Elemental ratios such as La/Sc, Cr /Ni, Co/Th, Th/Sc and Cr/Th indicate a mafic source for the marjority of each of the sandstone sequences. However, in several samples, high Th/Sc and low Cr/Th ratios suggest a contribution from a felsic source. Using element-ratio diagrams, all of the samples plot along a curve consistent with a two-component mixing model, consisting of a dominant mafic and a subordinate felsic source. The relatively low Cr/Ni ratios provide no support for significant amounts of ultramafic lithologies in the source area. The lower trace-element contents of the studied sandstones in relation to post-Archean Australian shales (PAAS), which are representative of the composition of the upper continental crust, indicate that recycling processes in their source areas were probably less intense than those of the PAAS. The more LREE-depleted patterns of the shales relative to sandstones likely do not reflect changes in source-area composition but, rather, variations in mineral sorting, chemical weathering and/or sediment recycling. Chemical index of alteration (CIA) indices observed in the Lower Jurassic and Upper Cretaceous sediments (average of 53 & 46, respectively) suggest that their source area underwent moderate degrees of chemical weathering processes. However, an upward increase in the values of the CIA indices in the Lower Jurassic profiles may indicate that the source area gradually underwent more intense chemical weathering, possibly due to climatic and/or tectonic variations. On the other hand, an upward decrease in the CIA indices of the Upper Cretaceous profiles generally demonstrate that the sediments were derived from a relatively less-weathered source terrain, reflecting an increased erosion rate likely due to increasing tectonic activity. The compositional immaturity of the analysed sandstone samples is typical of subduction-related environments, and their SiO2/Al2O3 and K2O/Na2O ratios and Co, Sc, Th and Zr contents reflect their oceanic and continental-arc settings.
AtıfScopus88WoS82İncele - MakaleYalnız künye2009Yields and qualities of some red clover (Trifolium pratense L.) genotypes in crop improvement systems as livestock feed
Tavlas, Ayten; Yolcu, Halil; Tan, Mustafa
The objective of this study was to compare twenty-five genotypes of red clover (Trifolium pratense L.) in terms of yield (in 2000 - 2004) and quality performance (in 2000 - 2001) for animal feeding. The genotypes were evaluated for dry matter yield (DMY), crude protein (CP), acid detergent fiber (ADF), neutral detergent fiber (NDF), digestible dry matter (DDM), dry matter intake (DMI), relative feed value (RFV), total digestible nutrients (TDN), net energy-lactation (NEl), net energy-maintenance (NEm) and net energy-gain (NEg) content. There were significant differences in DMY (P < 0.01), CP, ADF, NDF, DDM, DMI, RFV (P < 0.05), TDN, NEl, NEm and NEg (P < 0.01) amongst the genotypes. The Rajah cultivar had the highest DMY (13629 kg ha-1) amongst the genotypes according to five year results. While the highest CP (15.94%), NDF (50.59%), DDM (68.68%), TDN (66.50%), NEl (0.70 Mcal/1b), NEm (0.76 Mcal/1b) and NEg (0.44 Mcal/1b) were determined in the L-818 line, the lowest ADF (25.96%) was also found in the L-818 line. The highest DMI (3.16%) was observed in the Hamua cultivar. The highest RFV was determined in the Tohum Islah ecotype (156), the Hamua (155), the Orbit (154) cultivars and the L-812 (154) line. Our results showed that there were large variations in terms of yield and quality performances amongst the red clover genotypes for animal feeding. The Rajah, L-832 (selected from wild forms) and Pawera had the highest yields amongst the genotypes. The L-818, L-812 lines (selected from wild forms), Tohum Islah ecotype, Lucrun and Redwent cultivars were superior in terms of forage quality properties (low in ADF and NDF and high CP, DDM, DMI, RFV, TDN, NEl, NEm, NEg) than the other red clover genotypes.
AtıfScopus7WoS6İncele - MakaleYalnız künye2009Scopus SJRQ4Effects of various ages of weaning on growth performance of morkaraman lambs
Aksakal, Vecihi; Emsen, Ebru; Ozdemir, Memis; Macit, Muhlis
This study was conducted on 46 Redkaraman lambs born at the Ataturk University, Agricultural Faculty Sheep Research Farm. The lambs were weaned at different ages such as 45, 60 and 75 days. After weaning, the lambs were sent to the pasture and fed on concentrate including 15.3% crude protein in a ratio of 1.5% of live body weight for the first 6 weeks thereafter, amount of feed was increased to 2% of the live body weight in addition to pasture at the evenings. Live body weights and daily weight gaing of lambs were determined from 45 days to end of the grazing period within 14 days intervals. Live weights at 45 days for the lambs weaned at 45, 60 and 75 days were 12.20, 11.58 and 12.47 kg and at 60 days were 14.38, 14.79 and 15.40 kg and 75 days were 15.30, 16.06 and 17.28 kg. Live weights at the end of the grazing period were 34.86, 35.11 and 38.93 kg for the lambs weaned at 45, 60 and 75 days of age, respectively. The differences among the group were found significant (p<0.05) for live weights at the end of the grazing period. Daily weight gains of lambs in the groups were found as 144.5, 145.7 and 164.0 g for the end of the grazing period; 137.3, 142.6 and 160.5g for the 46 days of age and 136.5, 135.5 and 157.0 g for 61 days of age. The differences among the group were found significant (p<0.05). The results of this research indicated that there were significant (p<0.05) differences for the live weights at the end of the grazing period in Redkaraman lambs weaned at various ages, also there were significant (p<0.05) differences for daily weight gains at the end of the grazing period, 46 and 61 days of age.
AtıfScopus7WoS6İncele - MakaleYalnız künye2006Scopus SJRQ1Traditional wooden buildings and their damages during earthquakes in Turkey
Doǧangün, Adem; Tuluk, Ö.Iskender; Livaoǧlu, Ramazan; Acar, Ramazan
Wood is one of the oldest structural materials used in structures in many parts of the World. Woodframe buildings were also commonly constructed in Turkey until approximately 1960. After that, as reinforced concrete and masonry buildings have been preferred, wooden buildings have almost been forgotten. But, in 1999, Kocaeli and Duzce earthquakes reminded traditional buildings. Since reinforced concrete buildings presented high level of damage and traditional buildings relatively performed well during these earthquakes. In this study, types of traditional wooden buildings used in Turkey are mainly introduced and their damages in earthquakes are discussed. Damaged and undamaged wooden building photos are illustrated. Some structural weaknesses are highlighted by the earthquake damages including cracking and falling of plaster, failure of mortar, loosening or failing of connections, large lateral displacements, dislodgement of the masonry infill, loosening or failing of connections and failure of connections to foundation.
AtıfScopus112WoS92İncele - MakaleYalnız künye2009Scopus SJRQ1Multiobjective optimization of laminated composite cylindrical shells for maximum frequency and buckling load
Topal, Umut
This paper deals with multiobjective optimization of laminated cylindrical shells to maximize a weighted sum of the frequency and buckling load under external load. The layer fibre orientation is used as the design variable and the multiobjective optimization is formulated as the weighted combinations of the frequency and buckling under external load. The first order shear deformation theory is used for the finite element formulation of the laminated shells. Five shell configurations with eight layers are considered as candidate designs. The modified feasible direction method (MFD) is used as optimization routine. For this purpose, a program based on FORTRAN is used for the optimization of the laminated shells. Finally, the effect of different weighting ratios, shell aspect ratio, shell thickness-to-radius ratios and boundary conditions on the optimal designs is investigated and the results are compared.
AtıfScopus64WoS56OpenAlex63İncele - MakaleYalnız künye2008The rift-related Late Cretaceous drowning of the Gümüşhane carbonate platform (NE Turkey)
Yilmaz, Cemil; Carannante, Gabriele; Kandemir, Raif
In the Gümüşhane region (NE Turkey), carbonate platform and basin deposits, crop out with excellent exposures. In this area, two localities (Mescitli-İkisu region, 10 km west of the Gümüş hane and Kale-Kilop region, 20 km southeast of the Gümüşhane), in which the related successions are particularly well exposed, have been studied in detail. The outcropping shallow water limestones of the Berdiga Formation (Eastern Pontides Carbonate Platform) were deposited during Late Jurassic-Cenomanian p.p. times in peritidal environments. The overlying Kermutdere Formation consists of monogenic breccias, calciturbidites, red pelagic limestone and siliciclastic turbidites, which were deposited in slope and basin environments. In the Gümüşhane region, the above Formations record the evolution from platform to basin settings in relation to an extensional regime set up in the Cenomanian. The tectonics-related drowning of the Eastern Pontides carbonate platform resulted in graben-semi graben basins in which deep marine sediments were deposited during Late Cretaceous times, having a wedge geometry.
AtıfScopus14İncele - MakaleYalnız künye2002Scopus SJRQ1Comparative study of behavior of reinforced concrete beams strengthened and repaired-strengthened by using V connecting bars and U connecting stirrups
Öztürk, H.; Ayvaz, Y.
The purpose of this study is to investigate the repairing and strengthening techniques for reinforced concrete beams and to compare the behaviors of beams strengthened and repaired-strengthened by two different techniques with each other and with the behaviors of monolithic beams. These comparisons are made separately for the load carrying capacity, displacement, ductility, rigidity change, and energy dissipation capacity. The results show that the repairing and strengthening techniques used in this study can be effectively used in the practice.
AtıfScopus5OpenAlex6İncele - MakaleAçık Erişim2009Membrane thermal stability at different developmental stages of spring wheat genotypes and their diallel cross populations; [Yazlık buǧday genotipleri ve diallel melez populasyonlarının farklı gelisme dönemlerinde yüksek sıcaklık membran kararlılıǧı]
Yildirim, Mehmet; Bahar, Bilge; Koç, Müjde; Barutçular, Celalettin
Membrane thermal stability (MTS) can be a significant selection criterion for heat stress tolerance. MTS is determined by measuring of electirical conductivity of aquause phase in which leaf tissue exposure to high temperature. This research was conducted to investigate the membrane stability assay measured by two different methods, namely MTS and relative injury (RI). The second objective of this experiment was to determine the effects of different growth stages of four spring wheat parents and their six half F2 diallel cross progenies grown in the field on membrane stability. Measurements were taken at different growth stages (seedling, stem elongation and early milk). The MTS and RI assays gave similar results at the three different growth stages. However, growth stages significantly affected the MTS and RI values of genotypes. Membrane stability parameters of genotypes decreased during the later developmental stages. Specific combining ability effects were superior to general combining ability effect for all measurements, indicating that membrane thermal stability was mediated mainly by non-additive gene actions. Membrane stability of flag leaf at the early milk stage was significantly correlated with grain yield. The parent of Genç 99 and 84ÇZT04 had low yield potential, whereas Chil's and Seri 82 had high yield potential. Grain yield, spike yield and kernel weight of F2 population were found higher than their parents. These results suggest that genetic variation among genotypes for membrane stability can be utilized in wheat breeding in heat-stressed environments.
AtıfScopus24WoS18OpenAlex21İncele - MakaleYalnız künye2009Scopus SJRQ1Frequency 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.
AtıfScopus13WoS13OpenAlex16İncele - MakaleYalnız künye2009Scopus SJRQ4Chemical 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.
AtıfScopus5WoS4İncele - MakaleYalnız künye2007Scopus SJRQ1Different modes of stress transfer in a strike-slip fault zone: An example from the North Anatolian Fault System in Turkey
Bektaş, Osman; Eyüboǧlu, Yener; Maden, Nafiz
The dextral North Anatolian Fault System (NAFS) extends for well over 1000 km from the compressive tectonic domain of eastern Anatolia into the broad and diverse tectonic domain of the western Anatolian, Marmara and Aegean regions. These different tectonic regimes are characterized by a narrow deformation zone in the east and a much broader deformation zone with multiple sub-parallel fault zones in the west. The spatial and temporal distribution of large historical and modern earthquakes (Mw>5) shows two distinctive macro-seismic zones in the eastern and western parts of the NAFS. The eastern macro-seismic zone, between the towns of Erzincan and Bolu, has produced a successive linear earthquake series parallel to the fault system over the last 500 years, suggesting that stress transfer along the fault occurred in a manner of 'Static Coulomb failure stress changes' through the entire elastic crust. In contrast, the western macro-seismic zone of the NAFS, in the Marmara region, has produced successive earthquake pairs on the parallel faults, implying 'dynamic stress changes', involving large-scale flow in the aseismic lower crust and the mantle.
AtıfScopus14WoS13İncele - MakaleYalnız künye2007Scopus SJRQ3Seismic behaviour of cylindrical elevated tanks with a frame supporting system on various subsoil
Livaoglu, Ramazan; Dogangun, Adem
The seismic responses of an elevated tank with a frame supporting system on various subsoils are investigated. The finite element method is used for the modelling of the elevated tank and subsoil system. Fixed-base and elastic media assumptions are made for subsoil. The tank fluid has been modelled as lumped masses such as impulsive and convective masses proposed by Housner. An added mass approach is used for fluid-structure interaction by representing both the impulsive mass and the convective mass. For estimating the seismic response of elevated tanks, response spectrum analysis with mode superposition is used. The results obtained from modelling the elevated tanks on a fixed base and on an elastic medium are compared. It has been observed that the seismic response of the elevated tank is altered significantly depending on the properties of the subsoil. The soil-structure interaction especially affects the impulsive modes and lateral displacement of elevated tanks rather than the torsional modes. It is proposed that the coupling effect for perpendicular directions in the axisymmetrical plan geometry should be considered in the seismic design of the elevated tanks.
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