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81.
Can Balkaya S. Bahadir Yuksel Okan Derinoz 《The Structural Design of Tall and Special Buildings》2012,21(6):416-430
Shear‐wall dominant reinforced concrete buildings constructed with tunnel‐form technique are prevalently constructed in regions with high seismicity due to their ease of construction and inherent resistance to lateral forces. However, the current seismic codes and the design provisions constitute inadequate guidelines for the earthquake‐resistance design of these buildings. In particular, the prediction of their fundamental periods via current empirical expressions yields not only erroneous results, but also ignores soil‐structure interaction (SSI) effects. For the objective of understanding their dynamic characteristics, a series of eigen analyses is conducted with and without considering SSI effects. The soil effects on foundations are represented by linear translational and rotational winkler springs, and rigidities of the springs are computed from the foundation size and the uniform soil compressibility. An ensemble of 140 different shear‐wall dominant buildings with varying heights is simulated in three‐dimensions considering four different soil conditions. It is proven that the vibration periods and the mode shapes of the shear‐wall dominant buildings may change depending on the different soil conditions. Based on the results of the three dimensional finite element analyses, a set of new empirical equations was proposed to predict the fundamental periods of the shear‐wall dominant buildings accounting the SSI effects. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
82.
Okan Zafer Yeşilel Hakan Erer Mustafa Odabaşoğlu Orhan Büyükgüngör 《Journal of Inorganic and Organometallic Polymers and Materials》2010,20(1):78-82
A novel Cu(II) coordination polymer of general empirical formula {[Cu(μ-HC2O4)2(H2O)2][Cu(HC2O4)2]∙6H2O}
n
(1) has been synthesized and characterized by single-crystal X-ray diffraction technique. The complex (1) crystallizes in the triclinic form with P-1 space group. It is quite surprising that single crystal X-ray analysis of 1 illustrates the presence of hydrogen oxalate ligand in the coordination environment of Cu(II) ion. Because oxalate is not
present in the starting reaction mixture, it may be derived from the reduction of squarate ligand. In 1, Cu(II) ions exhibit two different coordination environments, forming a distorted octahedral geometry. The Cu1 is coordinated
with six oxygen atoms from two bidentate HC2O4
− and two aqua ligands, while Cu2 is coordinated with six oxygen atoms from four HC2O4
− ligands. The HC2O4
− ligand acts in two different coordination modes, as a bidentate and an unprecedented tridentate bridging coordination mode. 相似文献
83.
Hakan Erer Okan Zafer Ye?ilel Orhan Büyükgüng?r 《Journal of Inorganic and Organometallic Polymers and Materials》2010,20(4):774-782
Three M(II)-squarate complexes, [Co(sq)(H2O)(Nmim)4] (1), [Zn(μ1,3-sq)(H2O)2 (Nmim)2]
n
(2) and [Cd(μ1,3-sq)(H2O)2(Nmim)2]
n
(3) (sq = squarate, Nmim = N-methylimidazole) have been synthesized and characterized by elemental, spectral (IR and UV–Vis.) and thermal analyses. The
molecular structures of the complexes have been investigated by single crystal X-ray diffraction technique. The squarate ligand
acts as two different coordination modes as a monodentate (in 1) and bis(monodentate) (O
1–
O
3
) bridging ligand (in 2, 3). The Co(II) atom has a distorted octahedral geometry with the basal plane comprised of three nitrogen
atoms of Nmim ligands and a oxygen atom of squarate ligand. The axial position is occupied by a nitrogen atom of Nmim and
one aqua ligand. The crystallographic analysis reveals that the crystal structures of 2 and 3 are one-dimensional linear chain
polymers along the c and b axis, respectively. The configuration around each metal(II) ions are distorted octahedral geometry
with two nitrogen atoms of trans-Nmim, two aqua ligands and two oxygen atoms of squarate-O1,O3 ligand. These chains are held together by the C–H···π, π···π and hydrogen-bonding interactions, forming three-dimensional network. 相似文献
84.
Güne? Süheyla Kürk?üo?lu Dursun Karaa?a? Okan Zafer Ye?ilel Murat Ta? 《Journal of Inorganic and Organometallic Polymers and Materials》2012,22(2):324-331
Two novel cyano-bridged heteropolynuclear complexes, [Zn(mprd)2Ni(μ-CN)4]n (1) and {[Cd(mprd)2Ni(μ-CN)4]·2H2O}n (2), (mprd = 4-methylpyrimidine), have been synthesized and characterized by FT-IR spectroscopy, Raman spectroscopy, thermal
analyses (TG, DTG and DTA) and elemental analyses. The crystal structure of the 1 was determined by X-ray single crystal diffraction. The complex crystallizes in the monoclinic, space group C2/c. The crystal
structure of 1 consists of a corrugated 2D network in which the Zn(II) and Ni(II) atoms are linked by cyanide groups. The Ni(II) atom is
four coordinate with four carbon atoms in a square-planar geometry; and, the Zn(II) atom is six coordinate with four cyanide-nitrogen
and two mprd-nitrogen atoms with a distorted octahedral geometry. The shifts of the cyano stretching vibration are evidence
for the formation of cyano bridges. Vibration assignments are given for all the observed bands and the spectral features support
the structure of the polymeric complexes. 相似文献
85.
Ontology-enabled pervasive computing applications 总被引:1,自引:0,他引:1
Information technology's rapid evolution has made tremendous amounts of information and services available at our fingertips. However, we still face the frustration of trying to do simple things in the device- and application-rich environments where we live and work. Task computing is defined as computation to fill the gap between the tasks that users want to perform and the services that constitute available actionable functionality. To support task computing, we have implemented a Task Computing Environment including client environment, service discovery mechanism, and Semantic Web services and tools. TCE is composed of several components including STEER (Semantic Task Execution EditoR), White Hole, and PIPE (Pervasive Instance Provision Environment). 相似文献
86.
Enis Arik Hakan Altan Okan Esenturk 《Journal of Infrared, Millimeter and Terahertz Waves》2014,35(9):759-769
In this study we have investigated the dielectric properties of diesel and gasoline in the Terahertz (THz) spectral region. We present frequency dependent absorption coefficients, refractive indices, and dielectric constants calculated from the transient measurements of the fuel oils between 0.1 and 1.1 THz. Observed weak absorption coefficient of fuel oils is explained by transient dipole moments induced by collisions between individual molecules. Fuel oils were modeled successfully with Debye model to investigate the relaxation dynamics after interaction with the electric field. Significant differences in relaxation times of molecules in diesel and gasoline are attributed to the differences in their intermolecular forces. Dispersion forces are much greater in diesel due to the longer hydrocarbon chains (C8-C40) compared to that (C4-C12) of the gasoline. This leads to a comparably faster relaxation right after THz electric field is applied. Clear differences in optical properties offer a simple yet effective way to discriminate fuel oils from each other by using THz spectroscopy without any danger of combustion or decomposition of the samples. Such an approach may also be used for the quality determination of either fuels. The study presents the great potential of THz spectroscopy to study very complex mixtures like fuel oils by the use of instantaneous THz wave/matter interactions and relaxation dynamics of the constituent molecules. 相似文献
87.
Broccoli (Brassica oleracea L. var. Italica) florets were packaged in low‐density polyethylene (LDPE) bags with or without ethylene adsorber under passive modified atmosphere and then stored at 4°C for 20 days. LDPE films with (8% Tazetut® masterbatch, M2) or without ethylene adsorber (M1) were tested. The effects of modified atmosphere packaging treatments on gas concentrations (O2, CO2 and ethylene) in the headspace, the mass loss, colour, texture, pH, total soluble solids, chlorophyll content, total phenolic content and sensory quality of packaged broccoli were determined by comparing with unpackaged (control) florets. Results revealed that deterioration occurred quickly in control broccoli, manifested mainly by mass loss, chlorophyll degradation and stem hardening. Also, it was found unacceptable by sensory panel after 5 days. Conversely, in those florets packaged under modified atmosphere packaging, especially for LDPE with ethylene adsorber (M2), all changes related with loss of quality were significantly reduced and delayed with time. Additionally, total soluble solids and total phenolic content remained almost unchanged during the whole period. Ethylene concentration was determined as 61.8 ppm in M1 and 0.33 ppm in M2, respectively, at the end of the storage. Thus, broccoli packaged with M2 films had prolonged storability up to 20 days with high quality attributes, this period being only 5 days in unpackaged control broccoli. Oxygen concentration decreased below 1% after 5 days of storage in M1, and the shelf life of broccoli in these bags was limited to 5 days because of risk for anaerobic fermentation. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
88.
A. V. Sirin T. I. Krasnenko V. G. Mizin T. P. Sirina M. V. Rotermel’ O. S. Pozdnyakova 《Metallurgist》2006,50(11-12):565-570
A study of model systems that include sodium vanadate, sulfates of nickel, iron, and calcium, and a soda solution made it possible to determine the optimum parameters for desulfurizing high-sulfur wastes formed in the operation of heating and power plants. It is shown that when Ni/V = 0.15–0.33 and Fe/V = 0.5–0.75, 98% of the vanadium and 99.8% of the nickel are precipitated and sulfur content is no greater than 0.2 mass%. This has made it possible to obtain concentrates suitable for the smelting of complex alloys. 相似文献
89.
Integration of GIS with USLE in Assessment of Soil Erosion 总被引:9,自引:1,他引:8
A Geographic Information System (GIS) has been integrated with the USLE (Universal Soil Loss Equation) model in identification of rainfall-based erosion and the transport of nonpoint source pollution loads to the Gediz River, which discharges into the Aegean Sea along the western coast of Turkey. The purpose of the study is to identify the gross erosion, sediment loads, and organic N loads within a small region of the Gediz River basin. Similar studies are available in literature, ranging from those that use a simple model such as USLE to others of a more sophisticated nature. The study presented here reflects the difficulties in applying the methodology when the required data on soil properties, land use and vegetation are deficient in both quantity and quality, as the case is with most developing countries. 相似文献
90.
A model for flow sheet calculations of solvent extraction processes in reprocessing of Th-based spent fuels is proposed and two computer programs, one for extraction section and the other for scrubbing section calculations, are developed. Recoveries and decontamination factors are calculated for a standard Thorex method used for reprocessing Th-based spent fuels. Results compare well with those in literature and the model provides a simple means to study the Thorex method. 相似文献