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Structural,electronic and elastic properties of YCu from first principles

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Journal of rare Earths 2009年第4期27卷 661-663页

作者： G.Ugur M.ivi S.Ugur F.Soyalp r.ellialt1oglu Department of Physics Gazi University Teknikokullar Ankara 06500 Turkey Department of Physics Yüzüncü Yll University Zeve Kampüsü Van 65080 Turkey Department of Physics Engineering Hacettepe University Beytepe Ankara 06800 Turkey

The structural, electronic and elastic properties of YCu compound in the B2 （CsCl） phase were investigated using the density functional theory （DFT） within the generalized gradient approximation （GGA）. The electronic density of states （DOS） obtained in this way accorded weU with the results of a recent study utilizing the full-potential linearized augmented plane wave （FLAPW） method. We also found that the density of d-states at the Fermi energy was low. The calculated equilibrium properties such as lattice constant, bulk modulus and its first derivative, and the elastic constants were in good agreement with experimental and theoretical results.

关键词： YCu, electronic band structure, density of states, elastic constants, bulk modulus, ab initio rare earths

Seasonal variations of PM10 -- Trace elements, PAHs and Levoglucosan: rural sugarcane growing area versus coastal urban area in Southeastern Florida, USA. Part II: Elemental concentrations

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Particuology 2019年第5期17卷 99-108页

作者： Orhan Sevim oglu Wolfgang F. rogge Department of Environmental Engineering Cebze Technical University Cebze Kocaeli 41400 Turkey School of Engineering and Sierra Nevada research Institute University of California Merced. 5200 North Lake Road Merced CA 95343 USA

The largest sugarcane-growing area in the United States is in South Florida. An estimated 7 million tons of dry sugarcane leafy biomass is removed from the fields before harvest by burning the leaves off the sugarcane stalks. Preharvest sugarcane leaf foliage burning is a major source of airborne particulate matter (PM), polycyclic aromatic hydrocarbons (PAHs), biogenic trace elements such as K, volatile hydrocarbons and other pollutants. In one harvesting period, approximately 22 million tons of C02, a greenhouse gas, is released, 7 million tons from leaf foliage preharvest burning alone and 15 million tons from burning sugarcane bagasse in the sugar mills for power generation. In this study, PMio was collected from Belle Glade, close to the sugarcane-growing area, and from Delray Beach, an urbanized area along the East Coast of Florida. The PM samples were analyzed for trace elements and close to organic compounds. To elucidate the importance of preharvest sugarcane biomass smoke emissions on air quality, 39 trace elements, 18 PAHs, and levoglucosan were selected to apportion ambient PM constituents. Al, Ca and to a great extend also Mg are the major soil-related trace elements and key markers for fugitive soil dust emissions. Similarly, sea salt aerosol blown from the Atlantic Ocean into Florida added appreciably to PMio trace elements concentration, especially Na and Cl. Approximately half of the sea salt aerosol (PMjo -portion) by mass is removed from the atmosphere during the transport of ocean air from Delray Beach to Belle Glade. Ambient acid displacement reactions caused a substantial portion of the Cl (30%) to be liberated from the sea salt aerosol to the atmosphere during transport as gaseous HC1. The PAH concentrations at Belle Glade were high when the biomass combustion markers levoglucosan and Irations. This indicates that during the sugarcane harvest season, when leaf foliage is burned off just before harvest, most of

关键词： Urban versus rural Trace elements Sugarcane burning rare earth elements Sea salt aerosol Potassium Levoglucosan PAHs

Comparative Effect of an Addition of a Surface Term to Woods-Saxon Potential on Thermodynamics of a Nucleon

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Communications in Theoretical Physics 2018年第1期69卷 23-27页

作者： B.C.Lütfüoglu Department of Physics Akdeniz University

In this study, we reveal the difference between Woods-Saxon(WS) and Generalized Symmetric WoodsSaxon(GSWS) potentials in order to describe the physical properties of a nucleon, by means of solving Schr¨odinger equation for the two potentials. The additional term squeezes the WS potential well, which leads an upward shift in the spectrum, resulting in a more realistic picture. The resulting GSWS potential does not merely accommodate extra quasi bound states, but also has modified bound state spectrum. As an application, we apply the formalism to a real problem,an α particle confined in Bohrium-270 nucleus. The thermodynamic functions Helmholtz energy, entropy, internal energy,specific heat of the system are calculated and compared for both wells. The internal energy and the specific heat capacity increase as a result of upward shift in the spectrum. The shift of the Helmholtz free energy is a direct consequence of the shift of the spectrum. The entropy decreases because of a decrement in the number of available states.

关键词： Woods-Saxon potential generalized symmetric Woods-Saxon potential bound states analytical solutions partition function thermodynamic functions

Characterization of Microstructural and Morphological Properties in As-deposited Ta/NiFe/IrMn/CoFe/Ta Multilayer System

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Journal of Materials Science & Technology 2014年第4期30卷 359-364页

作者： ramis Mustafa ksoglu Umut Sarac Mustafa Yildirm Hakan inar Department of Materials Sciences and Engineering University of Anadolu Department of Elementary Education University of Bartin

Surface morphology and its relationship with microstructure in Ta/NiFe/IrMn/CoFe/Ta multilayer system deposited by pulsed DC magnetron sputtering have been investigated in dependence of Ta buffer and NiFe seed layer thicknesses using atomic force microscopy. The structural parameters such as grain size, dislocation density, texture and strain were calculated. For each surface, a self-affinity behavior with mean fractal dimensions in the range of 2.03-2.18 was found. Additionally, it was also observed that the surface of all samples has locally smooth textured surface structure in the short range. The texture aspect parameter and texture direction index have been obtained for isotropy/anisotropy surface texture. A significant relationship between the surface texture and the strength of the 〈111〉 texture in IrMn layer has been found. The analysis indicated that the surface roughness is strongly affected by the thicknesses of the NiFe seed and Ta buffer layers.

关键词： Pulsed DC magnetron sputtering Surface roughness Strain and texture

Laser Stimulation of the Chloroplast/Endoplasmic reticulum Nexus in Tobacco Transiently Produces Protein Aggregates （Boluses） within the Endoplasmic reticulum and Stimulates Local Er remodeling

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Molecular Plant 2011年第5期4卷 886-895页

作者： Lawrence r. Griffing1 3258 TAMU Biology Department Texas A＆M University College Station Texas 77843 USA

Does the Er subdomain that associates with the chloroplast in vivo, hereafter referred to as the chloroplast/Er nexus, play a role in protein flow within the Er？ In studies of tobacco cells either constitutively or transiently expressing Er-retained luminal, GFP-HDEL, or trans-membrane, YFP-rHD3, fluorescent fusion proteins, brief 405-nm （3-6-mW） laser stimulation of the nexus causes a qualitative difference in the movement and behavior of proteins in the Er. Photostimulating the nexus produces fluorescent protein punctate aggregates （boluses） within the lumen and membrane of the Er. The aggregation propagates through the membrane network throughout the cell, but within minutes can revert to normal, with disaggregation propagating back toward the originally photostimulated nexus. In the meantime, the Er grows and anastomoses around the chloroplast, forming a dense cisternal and tubular network. If this network is again photostimulated, bolus formation does not recur and, if the photostimulation results in photobleaching, fluorescence recovery after photobleaching occurs as it would typically in areas away from the nexus. Bolus propagation is not mediated by the actin cytoskeleton, but can be reversed by pre-conditioning the cells for 30 min with high, 40-45℃, temperature （heat stress）. Because it is not reversed with heat stress, the reorganization of the Er at the nexus following photostimulation is a separate event.

关键词： Er-chloroplast transport Er movement actin heat stress fluorescence recovery after photobleaching blue light reception.

Occurrence mechanism of silicate and aluminosilicate minerals in Sarcheshmeh copper flotation concentrate

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International Journal of Minerals,Metallurgy and Materials 2009年第5期16卷 494-499页

作者： H.r.Barkhordari1 E.Jorjani1 A.Eslami M.Noaparast Mining Engineering Department Science and Research BranchIslamic Azad UniversityPoonakHesarakTehranIran r&D Division-Sarcheshmeh Copper Complex RafsanjanIran School of Mining Engineering University College of EngineeringUniversity of TehranTehranIran

The Sarcheshmeh copper flotation circuit is producing 5× 10^4 t copper concentrate per month with an averaging grade of 28% Cu in rougher, cleaner and recleaner stages. In recent years, with the increase in the open pit depth, the content of aluminosilicate minerals increased in plant feed and subsequently in flotation concentrate. It can motivate some problems, such as unwanted consumption of reagents, decreasing of the copper concentrate grade, increasing of Al2O3 and SiO2 in the copper concentrate, and needing a higher temperature in the smelting process. The evaluation of the composite samples related to the most critical working period of the plant shows that quartz, illite, biotite, chlorite, orthoclase, albeit, muscovite, and kaolinite are the major Al2O3 and SiO2 beating minerals that accompany chalcopyrite, chalcocite, and covellite minerals in the plant feed. The severe alteration to clay minerals was a general rule in all thin sections that were prepared from the plant feed. Sieve analysis of the flotation concentrate shows that Al2O3 and SiO2 bearing minerals in the flotation concentrate can be decreased by promoting the size reduction from 53 to 38 μm. Interlocking of the Al2O3 and SiO2 bearing minerals with chalcopyrite and chalcocite is the occurrence mechanism of silicate and aluminosilicate minerals in the flotation concentrate. The dispersed form of interlocking is predominant.

关键词： copper aluminosilicate silicate flotation

Modified strip saturated models for two equal collinear cracks with coalesced zones in piezoelectric media

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Applied Mathematics and Mechanics(English Edition) 2019年第8期40卷 1097-1118页

作者： S.SINGH1 K.SHArMA r.r.BHArGAVA Department of Sciences and Humanities National Institute of Technology Uttarakhand Srinagar 246174India Department of Mathematics Indian Institute of Technology Roorkee Roorkee 247667India

Two equal collinear cracks with coalesced interior electric saturation zones are analytically studied for two-dimensional (2D) arbitrary polarized semipermeable piezo- electric media based on a modified strip saturated model. The strip saturated model is modified here by varying the strip saturated constant electric displacement condition to the polynomially varying electric displacement conditions. Based on the linear, quadratic, and cubic electric displacement conditions on the inner and outer saturated zones, dif- ferent modified strip saturated models are proposed and studied for two equal collinear cracks. With the Stroh formalism and the complex variable technique, these fracture problems are reduced into different types of non-homogeneous riemann Hilbert problems in unknown generalized complex potential functions. These mathematical problems are then solved with the riemann-Hilbert approach to obtain the stress and electric displace- ment components at any point of the domain. The explicit expressions for the outer saturated zone length, the crack opening potential (COP), the crack opening displace- ment (COD), and the local intensity factors (LIFs) are derived. A numerical study is presented for the modified strip saturated model in 2D arbitrary polarized semiperme- able PZT-4 material. The obtained results are compared with those of the strip saturated model, and the effects of the polynomially varying saturation condition on the saturated zones and the applied electrical loadings are presented.

关键词： complex variable coalesced zone piezoelectric riemann-Hilbert problem strip saturated model

A Preliminary Study of the Noninvasive remote Control System for rat Bio-robot

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Journal of Bionic Engineering 2010年第4期7卷 375-381页

作者： Xitian Pi~(1,2),Shuangshuang Li~1,Lin Xu~1,Hongying Liu~1,Shenshan Zhou~1,Kang Wei~1,Zhenyu Wang~1,Ziru Jia,Xiaolin Zheng~(1,2),Zhiyu Wen~2 1.Bioengineering College,Chongqing University,Chongqing 400030,P.r.China 2.Key Laboratories for National Defense Science and Technology of Innovative Micro-Nano Devices and System Technology,Chongqing University,Chongqing 400030,P.r.China [a] Bioengineering College Chongqing University Chongqing 400030 P. R. China [b] Key Laboratories for National Defense Science Technology of Innovative Micro-Nano Devices System Technology Chongqing University Chongqing 400030 P. R. China

A system is described here that can noninvasively control the navigation of freely behaving rat via ultrasonic,epidermaland LED photic stimulators on the *** system receives commands from a remote host computer to deliver specifiedelectrical stimulations to the hearing,pain and visual senses of the rat *** results demonstrate that the three stimuliwork in groups for the rat *** can control the rat to proceed and make right and left turns with great *** verified that the rat was able to reach a setting destination in the way of cable with the help of a person through theappropriate coordination of the three *** telemetry video camera mounted on the head of the rat also achieveddistant image acquisition and helped to adjust its navigation path over a distance of 300 *** a word,the non-invasive motioncontrol navigation system is a good,stable and reliable bio-robot.

关键词： rat navigation bio-robot ultrasonic stimulator epidermal stimulator LED photic stimulator

GPS short-delay multipath estimation and mitigation based on least square method

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Journal of Systems Engineering and Electronics 2009年第5期20卷 954-961页

作者： Zhang Shengkang~(1,2),Wang Hongbo~(1,2),Yang Jun~(1,2) & He Leiming~(1,2) 1.Beijing Inst.of radio Metrology and Measurement,Beijing 100854,P.r.China 2.National Key Laboratory of Metrology and Calibration Technology,Beijing 100854,P.r.China Beijing Inst. of radio Metrology and Measurement Beijing 100854 P. R. China National Key Laboratory of Metrology and Calibration Technology Beijing 100854 P. R. China

The GPS multipath signal model is presented, which indicates that the coherent DLL outputs in multipath environment are the convolution between the ideal DLL outputs and the channel responses. So the channel responses can be estimated by a least square method using the observed curve of the DLL discriminator. In terms of the estimated multipath channels, two multipath mitigation methods are discussed, which are equalization filtering and multipath subtracting, respectively. It is shown, by computer simulation, that the least square method has a good performance in channels estimation and the multipath errors can be mitigated almost completely by either of the methods. However, the multipath subtracting method has relative small remnant errors than equalization filtering.

关键词： global positioning system short-delay least square method multipath mitigation.