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In Anatolia, throughout the centuries, caverns in tuffs have been used for food storage. The aim of this study is to investigate experimentally the dehumidification property of tuffs, and to confirm whether tuffs play any part in the humidity of the ecosystem in storage. According to tests carried out on the Eskisehir?CDerbent Ciftligi white tuffs and six different rock types from Turkey, it was found that the atmospheric moisture absorption ability of tuffs is relatively higher than those of other tested rocks. This suggests that the dehumidification property is a unique characteristic of tuffs. It may allow for the tuff walls to work as an air dehumidifier for storing food. 相似文献
42.
E. N. Ercan 《Astrophysics and Space Science》1988,147(1):145-156
The spectral analysis of the persistent X-ray flux from the bright galactic bulge X-ray source and an X-ray burster X1813–14=GX17+2 is presented. A model with a single thermal bremsstrahlung continuum plus iron emission line at 6.7 keV fits the lower and higher intensity state data reasonably well. The line feature observed here is reproduced by a single emission line at 6.7 keV with intrinsic line width less than 0.7 keV. The equivalent width of the line ranges between 52 and 43 eV, depending on the intensity state of the source. This implies that the observed line is mostly due to helium-like iron (Fexxv). The properties of the line suggest that line-emitting matter is located far outside the neutron star. 相似文献
43.
In this research, experimental applications have been performed to reduce blast induced vibrations in open pit mines. For
this purpose, artificial discontinuity zones such as barrier holes and trench were opened in a dragline panel of Seyitomer
Lignite Enterprise, Kutahya, Turkey. Peak particle velocities in front of and behind them were measured by seismographs. In
this way, their effect against vibration was observed and compared. Barrier holes were opened 24 m deep through 3 parallel
lines and aligned at 1 m spacing. On the other hand, the trench had 8 m depth and 4 m width. During the research, 209 measurements
were taken belonging to 105 explosions. Twenty-eight explosions were carried out in the barrier holes experiments and 77 explosions
were carried out in the trench experiments. A decrease in vibration of 14.3–18.5% was obtained behind the barrier holes while
a decrease of 24.8–58.1% was provided by the trench. 相似文献
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Ercan Özcan İftikhar Ahmed Abbasi Katica Drobne Abiraman Govindan Luigi Jovane Kamel Boukhalfa 《Geodinamica Acta》2016,28(3):160-184
The upper member of the Jafnayn Formation in Wadi Rusayl and Al Khoud, Seeb Area in north Oman contains Nemkovella stockari Less & Özcan, 2007, an Early Eocene orthophragminid recorded here for the first time from the Arabian Peninsula. N. stockari, the only orthophragminid identified in Jafnayn Formation, is quite distinct from any other species from Tethys in having spiral and orbitoidiform chambers around the isolepidine embryon developed before the onset of annular chambers. The Oman specimens exhibit equal-sized principal auxiliary chambers and symmetrical spirals and are assigned to N. stockari bejaensis Özcan, Boukhalfa & Scheibner, 2014, an advanced form of the N. stockari lineage. The associated alveolinids, revised in this study, rotaliids and other age-diagnostic foraminiferal taxa in the transgressive basal part of the upper member have enabled us to revise the age as middle Ilerdian (Early Eocene), assignable to SBZ 7/8 and 8; OZ 3/4. Integrating a new record of this species from Arabian Plate margin in Belen, S Turkey, and previous records from north Africa, N. stockari appears to be a diagnostic marker for the Early Eocene along the southern peri-Tethys platforms, facilitating the Tethyan correlation by orthophragminids. The palaeobiogeographic distribution of N. stockari is discussed. 相似文献
45.
Ercan Yüksel Faruk Karadoğan Hasan Özkaynak Arastoo Khajehdehi Ahmet Güllü Eleni Smyrou İhsan Engin Bal 《Bulletin of Earthquake Engineering》2018,16(2):707-729
Mild steel is relatively low-cost and easily accessible material to fabricate some structural members. It would be a significant advantage if seismic energy dissipaters that are used in structures constructed in the earthquake prone areas, could also be produced on site. In this paper, a promising seismic energy dissipater made of mild steel, so-called steel cushion (SC) is presented. It is provided experimental and analytical responses of SCs subjected to bi-axial loadings. SC rolls under the lateral loading that allows relocation of the plasticized cross-section. Henceforth, SC dissipates considerable amount of seismic energy. A series of tests were performed to achieve experimentally the behavior of SC subjected to longitudinal and transversal loading. Finite Element Models (FEMs) were also generated to reproduce the experimental backbone curves and to predict the bi-directional response properties for discrete transversal forces and plate thicknesses. Closed-form equations were derived to determine yield and ultimate forces and the corresponding displacements as well as location of the plasticized sections. The behavior of SC could either be projected by the FEMs with the exhibited parameters or by means of the proposed closed-form equations and the normalized design chart. 相似文献
46.
Ömer Feyzi Gürer Ercan Sanğu Muzaffer Özburan Alper Gürbüz Nuran Sarica-Filoreau 《International Journal of Earth Sciences》2013,102(8):2199-2221
Southwestern Turkey experienced a transition from crustal shortening to extension during Late Cenozoic, and evidence of this was recorded in four distinct basin types in the Mu?la–Gökova Gulf region. During the Oligocene–Early Miocene, the upper slices of the southerly moving Lycian Nappes turned into north-dipping normal faults due to the acceleration of gravity. The Kale–Tavas Basin developed as a piggyback basin along the fault plane on hanging wall blocks of these normal faults. During Middle Miocene, a shift had occurred from local extension to N–S compression/transpression, during which sediments in the Eskihisar–T?naz Basins were deposited in pull-apart regions of the Menderes Massif cover units, where nappe slices were already eroded. During the Late Miocene–Pliocene, a hiatus occurred from previous compressional/transpressional tectonism along intermountain basins and Yata?an Basin fills were deposited on Menderes Massif, Lycian Nappes, and on top of Oligo–Miocene sediments. Plio-Quaternary marked the activation of N–S extension and the development of the E–W-trending Mu?la–Gökova Grabens, co-genetic equivalents of which are common throughout western Anatolia. Thus, the tectonic evolution of the western Anotolia during late Cenozoic was shifting from compressional to extensional with a relaxation period, suggesting a non-uniform evolution. 相似文献
47.
The homogeneity of newly compiled 212 precipitation records in Turkey for the period 1973‐2002 was checked by the Standard Normal Homogeneity Test (SNHT) and Pettitt Test. Stations were considered inhomogeneous if at least one of the tests rejects the homogeneity. As a result, 43 out of 212 stations were found to be inhomogeneous. In addition, the previously detected Southern Oscillation (SO)‐related precipitation anomalies by the authors were quantified at each station using the gamma distribution. The observed SO‐related shifts in the median precipitation amounts expressed as gamma percentiles may be considered as a typical SO response of that station. The results of this study confirm the wet responses of Turkish precipitations to El Nino events, whereas those for La Nina events seem to be masked by sampling variations within the study period. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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The North Atlantic Oscillation (NAO) is a large‐scale mode of natural climate variability governing the path of Atlantic mid‐latitude storm tracks and precipitation regimes in the Atlantic and Mediterranean sectors. The primary focus of this study is to investigate the variability of lake levels in seven lakes scattered across Turkey using the method of continuous wavelet transforms and global spectra. The long winter (December, January, February and March) lake‐level series and the NAO index (NAOI) series were subjected to wavelet transform. The global wavelet spectrum (energy spectrum of periodicities) of lake levels and winter NAOI anomalies, in most cases, revealed a significant correlation. It was shown that the Tuz, Sapanca, and Uluabat lakes reflect much stronger influences of the NAO than the other four lakes. In contrast, weak correlations were found in the coastal areas of the Mediterranean and eastern Turkey. The periodic structures of Turkish lake levels in relation to the NAO revealed a spectrum between the 1‐year and 10‐year scale level. Although the periodicities of more than 10‐year scale levels were detected, explaining significant relations between the NAO and these long‐term periodicities remains a challenging task. The results of this study are consistent with the earlier studies concerning the teleconnection between the NAO and climate variables in Turkey. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献