排序方式： 共有8条查询结果，搜索用时 15 毫秒
1
1.
Abdullah Ates Funda Bilim Aydin Buyuksarac Attila Aydemir Ozcan Bektas Yasemin Aslan 《Surveys in Geophysics》2012,33(5):869-885
In this paper, aeromagnetic and gravity anomalies obtained from the General Directorate of Mineral Research and Exploration were subjected to upward continuation to 3?km from the ground surface to suppress shallow effects and to expose only regional, deep sources. Then, a reduction to pole (RTP) map of aeromagnetic anomalies was produced from the 3?km upward continued data. A sinuous boundary to the south of Turkey is observed in the RTP map that may indicate the suture zone between the Anatolides and African/Arabian Plates in the closure time of the Tethys Ocean. The sinuous boundary can be correlated with the recent palaeo-tectonic maps. The southern part of the sinuous boundary is quite different and less magnetic in comparison with the northern block. In addition, maxspots maps of the aeromagnetic and gravity anomalies were produced to find out and enhance the boundaries of tectonic units. Crustal thickness, recently calculated and mapped for the western Turkey, is also extended to the whole of Turkey, and the crustal thicknesses are correlated with the previous seismological findings and deep seismic sections. The average crustal thickness calculations using the gravity data are about 28?km along the coastal regions and increase up to 42?km through the Iranian border in the east of Turkey. Density and susceptibility values used as parameters for construction of two-dimensional (2D) gravity and magnetic models were compiled in a table from different localities of Turkey. 2D models indicate that all of the anomalous masses are located in the upper crust, and this could be well correlated with the earthquakes which occurred at shallow depths. 相似文献
2.
Stability constants for metal complexation to bidentate ligands containing negatively-charged oxygen donor atoms can be estimated from the following linear free energy relationship (LFER): log KML = χOO(αO log KHL,1 + αO log KHL,2) where KML is the metal-ligand stability constant for a 1:1 complex, KHL,1 and KHL,2 are the proton-ligand stability constants (the ligand pKa values), and αO is the Irving-Rossotti slope. The parameter χOO is metal specific and has slightly different values for five and six membered chelate rings. LFERs are presented for 21 different metal ions and are accurate to within approximately 0.30 log units in predictions of log KML values. Ligands selected for use in LFER development include dicarboxylic acids, carboxyphenols, and ortho-diphenols. For ortho-hydroxybenzaldehydes, α-hydroxycarboxylic acids, and α-ketocarboxylic acids, a modification of the LFER where log KHL,2 is set equal to zero is required. The chemical interpretation of χOO is that it accounts for the extra stability afforded to metal complexes by the chelate effect. Cu-NOM binding constants calculated from the bidentate LFERs are similar in magnitude to those used in WHAM 6. This LFER can be used to make log KML predictions for small organic molecules. Since natural organic matter (NOM) contains many of the same functional groups (i.e. carboxylic acids, phenols, alcohols), the LFER log KML predictions shed light on the range of appropriate values for use in modeling metal partitioning in natural systems. 相似文献
3.
Timber constructions have been widely suggested to be seismically resistant based on post-disaster reconnaissance studies. This observation has, however, remained to a large extent anecdotal due to the lack of experimental work supporting it, especially for certain timber architectural forms, including traditional timber frame “h?m??” structures. To fill this gap, the authors carried out an extensive full-scale testing scheme using frames of various geometrical configurations, tested under reverse-cyclic lateral loading with/without infill (brick and adobe) or cladding (ba?dadi and ?amdolma) (Aktas et al. in Earthq Spectra 30(4):1711–1732, 2014a, b). The tests concluded that h?m?? frames had high energy dissipation capabilities due mostly to nailed connections. Infill/cladding significantly helped improve stiffness and lateral load strength of the frames, and timber type did not seem to make a remarkable impact on the overall behaviour. The current paper, on the other hand, uses test data to calculate capacity/demand ratios based on capacity spectrum method and Eurocode 8 to elaborate more on the performance of “h?m??” structures under seismic loading. The obtained results are discussed to draw important conclusions with regards to how frame geometry and infill/cladding techniques affect the overall performance. 相似文献
4.
Yasemin Sisman 《Arabian Journal of Geosciences》2014,7(3):1223-1231
The Global Positioning System (GPS) has become a popular sensing system for positioning because it is free and always available and can be used in all weathers. However, the accuracy of GPS is dependent on the measurement factors selected by the surveyor. Therefore, the purpose of this research is to determine the optimal factors of the GPS positioning process. The selected process variables were measurement time and duration, recording interval, and mask angle. To determine the optimum conditions of these factors, a three-level Box–Behnken design was utilized. The results indicated that the optimum conditions of the experimental factors are 13 h as measurement time, 21.77 min as the measurement duration, 22.43 s as the range interval, and 8° as the mask angle. 相似文献
5.
Yasemin Oztekin Zafer Yazicigil Tolga Duran Hakan Dumrul Ersin Guler Ozcan Kocyigit 《洁净——土壤、空气、水》2010,38(10):921-926
In this study, electrochemical experiments were performed in non‐aqueous media in order to determine electrochemical behavior of some of the glyoxime derivatives (GDs). Phenylglyoxime (PG), p‐chloro‐phenylglyoxime (p‐CPG), and 1,2‐phenylendiamino‐p‐chlorophenylglyoxime (PACPG) were chosen as GDs. Pt wire, Ag/Ag+ (in 0.01 M AgNO3) and glassy carbon (GC) electrode were used as counter, reference, and working electrode, respectively. The multiscan cyclic voltammograms (CVs) of these compounds were registered in acetonitrile (MeCN) containing 0.1 M tetrabutylammonium tetrafluoroborat (TBATFB) at scan rate of 100 mV/s. The potential was swept from 0 to +2.0 V versus Ag/Ag+ (0.01 M). The CVs of GDs were compared with each other and the electrochemical behaviors of the compounds were investigated depending on the functional groups in their structures. The electrochemical characterization of these modified surfaces was performed and characterizations were compared with the chatacterization results of bare GC surfaces. The application areas for new surfaces were investigated. These results will be active in the disciplines of electrochemistry and industrial physical chemistry, and in related industrial fields at the dissemination of new information for scientific area. 相似文献
6.
Seismic risk assessment of buildings in urban areas: a case study for Denizli,Turkey 总被引：3，自引：2，他引：1
This study aims to carry out a seismic risk assessment for a typical mid-size city based on building inventory from a field
study. Contributions were made to existing loss estimation methods for buildings. In particular, a procedure was introduced
to estimate the seismic quality of buildings using a scoring scheme for the effective parameters in seismic behavior. Denizli,
a typical mid-size city in Turkey, was used as a case study. The building inventory was conducted by trained observers in
a selected region of Denizli that had the potential to be damaged from expected future earthquakes according to geological
and geotechnical studies. Parameters that are known to have some effect on the seismic performance of the buildings during
past earthquakes were collected during the inventory studies. The inventory includes data of about 3,466 buildings on 4,226
parcels. The evaluation of inventory data provided information about the distribution of building stock according to structural
system, construction year, and vertical and plan irregularities. The inventory data and the proposed procedure were used to
assess the building damage, and to determine casualty and shelter needs during the M6.3 and 7.0 scenario earthquakes, representing
the most probable and maximum earthquakes in Denizli, respectively. The damage assessment and loss studies showed that significant
casualties and economic losses can be expected in future earthquakes. Seismic risk assessment of reinforced concrete buildings
also revealed the priorities among building groups. The vulnerability in decreasing order is: (1) buildings with 6 or more
stories, (2) pre-1975 constructed buildings, and (3) buildings with 3–5 stories. The future studies for evaluating and reducing
seismic risk for buildings should follow this priority order. All data of inventory, damage, and loss estimates were assembled
in a Geographical Information System (GIS) database. 相似文献
7.
Comparison of Extraction Procedures for Assessing Soil Metal Bioavailability of to Wheat Grains 总被引：1，自引：0，他引：1
Agricultural soils have been analyzed to elucidate whether the trace metal distribution changes in relation to agricultural activities and to predict environmental risk. In addition to the extractability of Cu, Mn, Ni, Pb, and Zn in soils was compared by single extraction (hydrochloric acid (HCl), ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTPA), calcium chloride (CaCl2), water (H2O)), and sequential extraction procedures. The modified Community Bureau of Reference (BCR) sequential extraction procedure (three‐step) used to extraction of metals in soil samples. The extraction capacity of the analyzed metals was found by using single extraction procedures in the order: HCl > EDTA > DTPA > CaCl2 > H2O. A single correlation analysis was used to investigate the relationship between extractable metal concentrations in soil solutions and metal accumulation in wheat grains. Simple correlation analyses indicated that the extractable Pb and Ni of soils by HCl, EDTA, and DTPA single extraction procedures were significantly correlated with the metal contents of wheat grains. For CaCl2, H2O, and BCR extraction procedures there was a relatively poor correlation between the extractable Cu, Mn, Ni, Pb, and Zn of soils and metal contents of wheat grains. 相似文献
8.
Yasemin Bilici Alemdar Bayraktar Kurtuluş Soyluk Kemal Haciefendioğlu Şevket Ateş Süleyman Adanur 《Soil Dynamics and Earthquake Engineering》2009
In this paper, stochastic dynamic responses of dam–reservoir–foundation systems subjected to spatially varying earthquake ground motions are investigated using the displacement-based fluid finite elements. For this purpose, variable-number-node two-dimensional (2D) fluid finite elements based on the Lagrangian approach is programmed in FORTRAN language and incorporated into a computer program SVEM, which is used for stochastic dynamic analysis of solid systems subjected to spatially varying earthquake ground motion. The spatially varying earthquake ground motion model includes incoherence, wave-passage and site-response effects. The incoherence effect is examined by considering the Harichandran and Vanmarcke coherency model. The effect of the wave passage is investigated by using various wave velocities. Homogeneous medium and firm soil types are selected for considering the site-response effect where the foundation supports are constructed. The Sar?yar concrete gravity dam, constructed in Turkey is selected for numerical example. The ground motion is described by filtered white noise and applied to each support point of the 2D finite element model of the dam–reservoir–foundation system. The record of Kocaeli earthquake in 1999 is used in the analyses. Displacements, stresses and hydrodynamic pressures occurring on the upstream face of the dam are calculated for four cases. It is concluded that spatially varying earthquake ground motions have important effects on the stochastic dynamic response of dam–reservoir–foundation systems. 相似文献
1