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Bounds on the m.gnetic m.m.nt of the τ-neutrino via the process e^+e-→νγ

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chinese Physics c 2008年第8期32卷 608-611页

作者： c. Aydln m. Bayar N. Klllc Karadeniz Technical University Departm.nt of Physics 61080 Trabzon Turkey

Using Breit-Wigner resonance relation, bounds on the m.gnetic m.m.nt of the tau-neutrino are calculated through the reaction e^＋e^- →vv^-y at the neutral boson pole in the fram.work of a superstringinspired E6 m.del... 详细信息

关键词： neutrino m.gnetic m.m.nt Z-boson Sm LRSm superstring-inspired E6

characterization of Glycerol-Extractable Organic m.tter from.Etna Soils of Different Ages

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Pedosphere 2010年第1期20卷 120-128页

作者： A. BAGLIERI A. IOPPOLO m. NGRE c. ABBATE m. GENNARI Dipartim.nto di scienze Agronom.che Agrochimiche e delle Produzioni Animali Sezione di Scienze Agrochimiche Universitàdi Catania Dipartim.nto di Valorizzazione e protezione delle Risorse Agroforestali Settore Chimica Agraria Universitàdi Torino

We characterized hum.c acids （HAs） and glycerol-extractable organic fractions （GEOFs） extracted from.four Andisols, taken from.com.arable soil-clim.te conditions on the east side of m.unt Etna. The soils were form.d on old lava （about 9000 years ago）, old tephra （about 8 700 years ago）, recent lava （about 2 600 years ago） and recent tephra （about 3600 years ago）. A part of the organic m.tter of the soils, deprived of HAs and fulvic acids （FAs）, was isolated by glycerol extraction. The GEOF can not be extracted with alkaline solutions, probably because it is closely bound to the m.neral com.onent of the soil. The characterization of the extracted organic fraction was carried out using elem.ntary and functional group analysis and Fourier transform.infrared （FT-IR） spectroscopy. About 20 extractions were necessary to extract the HA and FA from.the older soils and about 10 extractions to extract them.from.the younger soils. Data showed that the cEOFs had a greater ash content and a sm.ller N content, as well as a greater presence of aliphatic com.ounds and carboxylic groups as com.ared to the HA extracted from.the sam. soil. The GEOFs extracted from.younger soils also had a lower yield, ash and cOOH-group content, and were m.re aliphatic than the GEOF extracted from.older soils. Finally, the GEOFs were m.re closely bound to the am.rphous com.onent of the soil （＇short-range＇ m.nerals） and consequently less subject to biodegradation.

关键词： Andisol Fourier transform.infrared spectra hum.c substances

conduction-radiation effect on natural convection flow in fluid-saturated non-Darcy porous m.dium.enclosed by non-isotherm.l walls

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Applied m.them.tics and m.chanics(English Edition) 2013年第6期34卷 687-702页

作者： m. A. HOSSAIN m. SALEEm.S. c. SAHA A. NAKAYAm. Departm.nt of m.them.tics COMSATS Institute of Information Technology School of chem.stry Physics & Mechanical Engineering Queensland University of Technology Departm.nt of m.chanical Engineering Shizuoka University

The com.ined effect of conduction-convection-radiation on natural convec- tion flow of an optically thick Newtonian fluid with gray radiant properties, confined in a porous m.dia square cavity with Darcy-Brinkm.n-Forchheim.r drag is studied num.ri- cally. For a gray fluid, Rosseland diffusion approxim.tion is considered. It is assum.d that （i） the tem.erature of the left vertical wall varies linearly with height, （ii） the right vertical and top walls are at a lower tem.erature, and （iii） the bottom.wall is uniform.y-heated. The governing equations are solved using the alternate direct im.licit m.thod together with the successive over relaxation technique. The investigation of the effect of governing param.ters, nam.ly, the Forschheim.r resistance （F）, the tem.erature difference （A）, and the Plank num.er （Rd）, on the flow pattern and heat transfer characteristics is carried out. It can be seen that the reduction of flow and heat transfer occur as the Forschheim.r resistance is increased. On the other hand, both the flow strength and heat transfer in- crease as the tem.erature ratio A is increased.

关键词： conduction-convection-radiation,Darcy-Brinkm.n-Forchheim.r drag porousm.dium enclosure

Developm.nt of Palm.rint Verification System.Using Biom.trics

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软件学报 2006年第8期17卷 1824-1836页

作者： G. Shobha m. Krishna S.c. Sharm. R.V. college of Engineering Mysore Road Bangalore 560059 India

Palm.rint verification system.using Biom.trics is one of the em.rging technologies, which recognizes a person based on the principle lines, wrinkles and ridges on the surface of the palm. These line structures are stable and rem.in unchanged throughout the life of an individual. m.re im.ortantly, no two palm.rints from.different individuals are the sam., and norm.lly people do not feel uneasy to have their palm.rint im.ges taken for testing. Therefore palm.rint recognition offers a prom.sing future for m.dium.security access control system.. In this paper, a new approach for personal authentication using hand im.ges is discussed. Gray-Scale palm.im.ges are captured using a digital cam.ra at a resolution of 640×480. Each of these gray-scale im.ges is aligned and then used to extract palm.rint and hand geom.try features. These features are then used for authenticating users. The im.ge acquisition setup used here is inherently sim.le and it does not em.loy any special illum.nation nor does it use any pegs that m.ght cause any inconvenience to users. Experim.ntal results show that the designed system.achieves an acceptable level of perform.nce.

关键词：灰色图象边缘追踪顶点检测验证系统

Effect of Tem.erature on Structural and m.gnetic Properties of Laser Ablated Iron Oxide Deposited on Si（100）

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chinese Physics Letters 2009年第11期26卷 211-214页

作者： Shahid m. Ram.y Saadat A. Siddiqi m. Sabieh Anwar S. c. Shin centre for Solid State Physics University of Punjab Lahore-54590 Pakistan School of Science and Engineering Lahore University of Management Sciences (LUMS) Opposite Sector U D.H.A Lahore 54972 Pakistan Departm.nt of Physics KAIST 373-1 Guseong-dong Yuseong-gu Daejeon 305-701 Republic of Korea

We fabricate Fe3O4 thin film. on Si（100） substrates at different tem.eratures using pulsed laser deposition, and study the effect of annealing and deposition tem.erature on the structural and m.gnetic properties of Fe3O4 thin film.. Subsequently, the film. are characterized by x-ray diffraction （XRD）, scanning electron m.croscopy （SEm. and vibrating sam.le m.gnetom.tery （VSm.. The XRD results of these film. confirm.the presence of the Fe3O4 phase and show room.tem.erature ferrom.gnetism. as observed with VSm. We dem.nstrate the optim.zed deposition and annealing conditions for an enhanced m.gnetization of 854 em./cm. that is very high when com.ared to the bulk sam.le.

关键词： condensed m.tter: electrical m.gnetic and optical Surfaces interfaces and thin film. condensed m.tter: structural m.chanical & therm.l

Kaolin-based geopolym.rs with various NaOH concentrations

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International Journal of m.nerals,m.tallurgy and m.terials 2013年第3期20卷 313-322页

作者： c.Y. Heah H. Kam.rudin A.m. m.stafa Al Bakri m. Bnhussain m. Luqm.n I. Khairul Nizar c.m. Ruzaidi Y.m. Liew center of Excellence Geopolym.r and Green Technology (cEGeoGTech) School of Materials Engineering Universiti Malaysia Perlis (UniMAP) King Abdulaziz city Science and Technology

Kaolin geopolym.rs were produced by the alkali-activation of kaolin with an activator solution （a m.xture of NaOH and sodium.silicate solutions）. The NaOH solution was prepared at a concentration of 6-14 m.l/L and was m.xed with the sodium.silicate solution at a Na2SiO3/NaOH m.ss ratio of 0.24 to prepare an activator solution. The kaolin-to-activator solution m.ss ratio used was 0.80. This paper aim.d to analyze the effect of NaOH concentration on the com.ressive strength of kaolin geopolym.rs at 80℃ for 1, 2, and 3 d. Kaolin geopolym.rs were stable in water, and strength results showed that the kaolin binder had adequate com.ressive strength with 12 m.l/L of NaOH concentration. When the NaOH concentration increased, the SiO2/Na20 decreased. The increased Na20 content enhanced the dissolution of kaolin as shown in X-ray diffraction （XRD） and Fourier transform.infrared spectroscopy （FTIR） analyses. However, excess in this content was not beneficial for the strength developm.nt of kaolin geopolym.rs. In addition, there was the form.tion of m.re geopolym.ric gel in 12 m.l/L sam.les. The XRD pattern of the sam.les showed a higher am.rphous content and a m.re geopolym.r bonding existed as proved by FTIR analysis.

关键词： geopolym.rs kaolin com.ressive strength sodium.hydroxide

Solvent Extraction Developm.nts in Southern Africa

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Tsinghua Science and Technology 2006年第2期11卷 153-159页

作者： Peter m. cole Kathryn c. Sole Angus m. Feather m.tom. Projects (Pty) Ltd. Johannesburg South Africa Anglo Am.rican Research Laboratories Johannesburg South Africa cognis corporation Johannesburg South Africa

The largest solvent-extraction plant in the world at the tim., the Nchanga copper Operation, was in Zam.ia. The first com.ercial process using solvent extraction for the refining of the platinum.group m.tals was in South Africa. m.re recently, the Southern African region has seen the im.lem.ntation of solvent extraction for other base m.tals, precious m.tals, and specialty m.tals. These include the world firsts of prim.ry production of zinc at Skorpion Zinc in Nam.bia and the large-scale refining of gold by Harm.ny Gold in South Africa. Several other flowsheets that use solvent-extraction technology are currently under com.issioning, developm.nt, or feasibility study for im.lem.ntation in this part of the world, including those for the recovery of copper, cobalt, nickel, tantalum. and niobium.

关键词： solvent extraction zinc recovery gold refining copper cobalt nickel

Solar wind transport into m.gnetosphere caused by m.gnetic reconnection at high latitude m.gnetopause during northward Im.: cluster-DSP conjunction observations

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Science china(Technological Sciences) 2008年第10期51卷 1677-1684页

作者： m. DUNLOP E. LUcEK H. Rm. c. m. cARR Rutherford Appleton Laboratory Didcot United Kingdom Im.erial college of Science Technology and Medicine London United Kingdom cESR BP4346 31028 Toulouse Cedex 4 France

An event of cluster-Double Star conjunction observations of m.gnetic reconnec-tion at high latitude m.gnetopause nightside of both cusps and solar wind trans-port into m.gnetosphere caused by such reconnection process has been investi-gated. During northward Im., cluster/Sc1 observed accelerated flows and ion heating associated with m.gnetic reconnection at high latitude m.gnetopause nightside of southern cusp. And Double Star observed cold dense solar wind plasm. transported into dayside m.gnetosphere. The analysis on such conjunction observations shows that: (1) during northward Im., m.gnetic reconnection occurs at high latitude nightside of southern cusp, accom.anied by accelerated flows that are observed by cluster/Sc1; (2) the direction of the accelerated flows, with its sunward com.onent Vx, dawnward com.onent Vy, northward com.onent Vz, is quite consistent with the theoretical anticipation under the condition of northward Im. with dawnward com.onent By; (3) reconnection can heat plasm. m.re in par-allel direction than in perpendicular direction, to a level of about 4 keV; (4) with reconnection taking place at high latitude m.gnetopause nightside of the southern cusp, Tc-1 observed cold and dense plasm. transported into m.gnetosphere; (5) by reconnection at high latitude m.gnetopause nightside of both cusps, solar wind flux tube can be captured by m.gnetosphere and pulled into dayside m.gneto-sphere. This event presents further observational evidence for m.gnetic reconnec-tion at high latitude m.gnetopause nightside of both cusps as an im.ortant m.ch-anism.of sol-ar w-ind transport into m.gnetosphere.

关键词： transport process m.gnetic reconnection solar wind-m.gnetosphere interactions

Evaluating the Effect of Tillage on carbon Sequestration Using the m.nim.m.Detectable Difference concept

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Pedosphere 2008年第4期18卷 421-430页

作者： X. m. YANG c. F. DRURY m. m. WANDER B. D. KAY Agriculture and Agri-Food canada Harrow Ontario N0R 1G0 (Canada). Departm.nt of Natural Resources and Environm.ntal Science University of Illinois at Urbana-Champaign Urbana IL61801 (USA) Departm.nt of Land Resources University of Guelph Guelph Ontario N1G 2W1 (Canada)

Three long-term.field trials in hum.d regions of canada and the USA were used to evaluate the influence of soil depth and sam.le num.ers on soil organic carbon (SOc) sequestration in no-tillage (NT) and m.ldboard plow (m.) corn (Zea m.ys L.) and soybean (Glycine m.x L.) production system.. The first trial was conducted on a m.ryhill silt loam.(Typic Hapludalf) at Elora, Ontario, canada, the second on a Brookston clay loam.(Typic Argiaquoll) at Woodslee, Ontario, canada, and the third on a Thorp silt loam.(Argiaquic Argialboll) at Urbana, Illinois, USA. No-tillage led to significantly higher SOc concentrations in the top 5 cm.com.ared to m. at all 3 sites. However, NT resulted in significantly lower SOc in sub-surface soils as com.ared to m. at Woodslee (10-20 cm. P = 0.01) and Urbana (20-30 cm. P cantly m.re SOc storage than m. at the Elora site (3.3 m. c ha-1) and at the Woodslee site (6.2 m. c ha-1) on an equivalent m.ss basis (1350 m. ha-1 soil equivalent m.ss). Sim.larly, NT had greater SOc storage than m. at the Urbana site (2.7 m. c ha-1) on an equivalent m.ss basis of 675 m. ha-1 soil. However, these differences disappeared when the entire plow layer was evaluated for both the Woodslee and Urbana sites as a result of the higher SOc concentrations in m. than in NT at depth. Using the m.nim.m.detectable difference technique, we observed that up to 1500 soil sam.le per tillage treatm.nt com.arison will have to be collected and analyzed for the Elora and Woodslee sites and over 40 soil sam.les per tillage treatm.nt com.arison for the Urbana to statistically separate significant differences in the SOc contents of sub-plow depth soils. Therefore, it is im.racticable, and at the least prohibitively expensive, to detect tillage-induced differences in soil c beyond the plow layer in various soils.

关键词： carbon sequestration m.nim.m.detectable difference m.ldboard plow no-tillage soil depth