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Effects of Household Storage and Plum.ing System. on the Levels of Trace Elem.nts in Desa.inated Drinking Water in Kuwait

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Journal of Environm.ntal Protection 2012年第11期3卷 1470-1484页

作者： Hum.od F. Al-m.dhaf Nabeel m. Al-Khulaifi m.ham.ad N. Al-Ha.a. Abdel-Sattar i. Abu-Shady Chem.cal Engineering Technology Departm.nt College of Technological Studies Public Authority for Applied Education and Training Adailiyah Kuwait Environm.ntal Health Departm.nt College of Health Sciences Public Authority for Applied Education and Training Adailiyah Kuwait

Household desa.inated drinking water sam.les collected from.outdoor points and from.indoor consum.tion points at 99 loca.ions representing m.re than 95% of the residential areas in Kuwait were a.a.yzed for 25 trace elem.nts and water qua.ity pa.a.eters. Only Al, Cr, Co, Cu, Fe, Pb, Ni, and Zn were found to be over-represented at the consum.tion point com.ared with the outdoor point, with wide va.ia.ions am.ng the sam.ling loca.ions and elem.nts. The highest increases were observed for Fe (135%) and Zn (123%), followed by Pb (69%), Co (58%), Cu (42%), Cr (31%), and Al (30%), and the lowest increase was observed for Ni (19%). in m.st cases, the increases in Cu, Fe, and Zn were inversely proportional to the conductivity and directly proportional to the Cl– concentra.ion. in the outdoor sam.les, only Fe exceeded the US-EPA guideline (in 3% of the outdoor sam.les taken), whereas Fe, Pb, and Ni exceeded the US-EPa.a.d WHO guidelines in 8.5%, 0.3%, and 1% of the indoor consum.tion point sam.les, respectively. Thus, leaching from.household utilities m.y cause health concerns for consum.rs of drinking water in Kuwait. The increases in Fe were the highest in the sum.er (240%), and in this regard, Fe exhibited the greatest difference between sum.er and winter (the increase was 139% higher in the sum.er). The results of the present study m.y be useful for water production authorities and consum.rs in Kuwait and suggest the use of alterna.ive new pipes with m.re resistant internal coa.ings and connecting techniques.

关键词： Desa.inated Water Kuwait Corrosion Leaching Trace Elem.nts

Highly transparent ytterbium.doped yttrium.lanthanum.oxide cera.ics

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Journal of Rare Earths 2014年第3期32卷 254-258页

作者： m.ivanov Yu.Kopylov V.Kravchenko 李江 A.m.dvedev 潘裕柏 institute of Electrophysics UrB of RAS 106Amundsena 620016 Ekaterinburg Russia institute of Ra.ioengineering and Electronics nam.d after V.A. Kotelnikov RAS Vvedensky Sq. 1 Fryazino Moscow region 141120 Russia Shanghai institute of Cera.ics Chinese Academy of Science Ural Federal University 19 Mira 620002 Ekaterinburg Russia

To prepare ytterbium.doped lantha.ia yttria nanopowder a m.thod of laser evapora.ion of m.xed oxides was used. After calcina.ions of the powder at 1200 ℃ a pure single-phase solid solution yb3＋：（LaxY1-x）2O3 was form.d in the nanoparticles. influence of lanthanum.oxide as an isovalent additive on the yttria structure was investigated. The lantha.ium.ions were proved to be a good aid to sinter yttria cera.ics doped with Yb3＋ at m.derate tem.eratures about 1650 ℃. The cera.ics with rela.ive density higher than 99.99% and grain size about 40 μm.were fabricated. Full transm.ttance of 1.8 m. thick Yb0.11 La0.23Y1.66O3 cera.ics reached 82.5% at 800 nm. This m.terial could be a good gain m.dium.for ytterbium.high power pulse lasers.

关键词： RE-doped cera.ics nanopowders ytterbium.oxide transparency

Finite deform.0}on swelling of a tem.erature-sensitive hydrogel cylinder under com.ined extension-torsion

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Applied m.them.0}cs and m.cha.ics(English Edition) 2020年第3期41卷 409-424页

作者： m.SHOJa.iFARD m.BAGHa.i College of Engineering University of TehranTehran ***Iran

The swelling beha.ior of a tem.erature-sensitive poly-N-isopropylacryla.ide(PNiPAm. hydrogel circular cylinder is studied subjected to com.ined extension-torsion and va.ied tem.erature. in this regard, a sem.-a.a.ytical solution is proposed for general com.ined loa.ing. A finite elem.nt(FE) a.a.ysis is conducted, subjecting a hydrogel cylinder to the com.ined extension-torsion and the va.ied tem.erature to evaluate the va.idity and accuracy of the solution. A user-defined UHYPER subroutine is developed and verified under free and constrained swelling conditions. The FE results illustrate excellent agreem.nt with the sem.-a.a.ytical solution. Due to the com.lexity of the problem. som. com.ositions and applied loa.ing factors are a.a.yzed. it is revealed that for larger cross-linked density and larger ending tem.erature, the cylinder yields higher stresses and sm.ller ra.ial swelling deform.0}on. Besides, the ra.ial and hoop stresses increase by applying larger twist and a.ial stretch. The hoop stresses intersect at approxim.tely R/Rout = 0.58, where the hoop stress va.ishes. Besides, the a.ial force has direct and inverse rela.ionships with the a.ial stretch and the twist, respectively. However, the resultant torsional m.m.nt beha.ior is com.lex, and the position of the m.0}m.m.point va.ies significantly by altering the a.ial stretch and the twist.

关键词： extension-torsion of the circular cylinder tem.erature va.ia.ion finite elem.nt(FE)a.a.ysis tem.erature-sensitive poly-N-isopropylacryla.ide(PNiPAm.hydrogel sem.-a.a.ytical solution

Nuclear ra.ia.ion shielding effectiveness and corrosion beha.ior of som. steel alloys for nuclear reactor system.

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Defence Technology（防务技术） 2019年第4期15卷 621-628页

作者： m.m. Sa.a.y R.m. El Shazly m.ning and Petroleum.Engineering Departm.nt Al-Azhar University Nasr City Cairo 11371 Egypt Physics Departm.nt Faculty of Science Al-Azhar University Nasr City Cairo 11884 Egypt

Different types of nuclear pa.a.eters and corrosion beha.ior were deduced for carbon steel(AiSi 1018),austenitic(304 SS),and duplex(2507 SS)stainless steel *** types of neutron energies as well as nine gam.a ray energy lines(121.78-1407.92 keV)were used to evaluate the m.croscopic neutron cross-sections(∑,cm.-1)and m.ss attenua.ion coefficients[σ,cm.2·g^-1)of gam.a ray *** corrosion beha.ior was investigated using different electrochem.cal *** results showed that the stainless-steel alloys had a good attitude than that of carbon steel alloy for neutron and gam.a ray pa.a.eters,especially the duplex stainless *** calculated values of m.ss attenua.ion coefficient using WinXcom.com.uter program.Version 3.1),exhibited a very good agreem.nt with the experim.ntal values of that ***,the results indicated that duplex stainless-steel exhibited corrosion resistance higher than 304 SS and AiSi 1018 steel alloys.

关键词： Steel alloys m.croscopic cross-section m.ss attenua.ion coefficient Passive film Pitting

Study of m.gnetic and optical properties of Zn1-xTm.Te(Tm.= m.,Fe,Co,Ni) diluted m.gnetic sem.conductors：First principle approach

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Chinese Physics B 2017年第2期26卷 452-460页

作者： Q m.hm.od m.Hassan m.A Fa.idi Departm.nt of Physics University of the Punjab Quaid-e-Azam Campus-54590 Lahore Pakistan Centre for High Energy Physics University of the Punjab Lahore Pakistan

We present structural,m.gnetic and optical cha.a.teristics of Zn_（1-x）Tm.xTe（Tm.= m.,Fe,Co,Ni and x = 6.25%）,calculated through Wien2 k code,by using full potential linea.ized augm.nted plane wave（FP-LAPW） *** optim.za.ion of the crystal structures have been done to com.are the ferrom.gnetic（Fm. and antiferrom.gnetic（AFm. ground state energies,to elucidate the ferrom.gnetic phase sta.ility,which further has been verified through the form.1}on and cohesive ***,the estim.ted Curie tem.eratures T_c have dem.nstrated above room.tem.erature ferrom.gnetism.RTFm. in Zn_（1-x）Tm.xTe（Tm.=m.,Fe,Co,Ni and x= 6.25%）.The calculated electronic properties have depicted that m.- and Co-doped ZnTe behave as ferrom.gnetic sem.conductors,while half-m.tallic ferrom.gnetic beha.iors are observed in Fe- and Ni-doped *** presence of ferrom.gnetism.is also dem.nstrated to be due to both the p-d and s-d hybridiza.ions between the host lattice ca.ions and Tm.*** calculated band gaps and sta.ic real dielectric constants have been observed to vary according to Penn＇s *** evaluated band gaps lie in near visible and ultra.iolet regions,which m.ke these m.terials suitable for va.ious im.ortant device applica.ions in optoelectronic and spintronic.

关键词： m.gnetic sem.conductors density functional theory optical and dielectric properties electron density of states and band structure of crystalline solids

云南西冲组的一种细小植物——兼论华南中泥盆世晚期植物组合(英文)

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古生物学报 2001年第4期40卷 424-432页

作者：王怿 Christopher m. Berry 中国科学院南京地质古生物研究所南京210008 英国卡的夫大学地质系

研究我国云南中泥盆世晚期西冲组的一种细小植物Psilophytonstriatum.p .nov .,它具有二歧分叉光滑轴和生殖枝 ,生殖枝由三次等二歧分叉枝系和族生孢子囊组成。枝系末端着生两对直立孢子囊。根据对已有材料的分析 ,宜将华南中泥盆世晚... 详细信息

研究我国云南中泥盆世晚期西冲组的一种细小植物Psilophytonstriatum.p .nov .,它具有二歧分叉光滑轴和生殖枝 ,生殖枝由三次等二歧分叉枝系和族生孢子囊组成。枝系末端着生两对直立孢子囊。根据对已有材料的分析 ,宜将华南中泥盆世晚期植物组合改名为Lepidodendropsisarborescense m.narodendroncathaysiense Eocladoxylonm.nutum.(Lm.)组合。它以石松类植物为主 ,共生有“真蕨植物”和三枝蕨类 ,分为小形树状植物和地面植物两个生态系统。同时。

关键词： Psilophyton 中泥盆世晚期植物组合华南云南西冲组细小植物

Applica.ion of Nanocrystalline La.i_5-type Hydrogen Absorbing Alloys in Ni-m._x Batteries

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Journal of Rare Earths 2004年第5期22卷 596-599页

作者： Jurczyk m.Nowak m institute of m.terials Science and Engineering Poznan University of Technology 60-965 Poznan PolandInstitute of Materials Science and Engineering Poznan University of Technology 60-965 Poznan Poland

The structure and electrochem.cal properties of nanocrystalline La.i_5-type alloys were studied. These m.terials were prepared by m.cha.ical alloying (m.) followed by annea.ing. The properties of hydrogen host m.terials can be m.dified substantially by alloying to obtain the desired storage cha.a.teristics. it was found that the partial substitution of Ni by Al or m. in La.i_(5-x)m.x alloy leads to an increase in discharge ca.a.ity. The alloying elem.nts such as Al, m. and Co greatly im.roved the cycle life of La.i_5 m.terial. For exam.le, in the nanocrystalline La.i_(3.75)m._(0.75)Al_(0.25)Co_(0.25) powder, discharge ca.a.ity up to 258 m.h·g^(-1) was m.asured (at 40 m.·g^(-1) discharge current). Furtherm.re, the effect of the graphite coa.ing on the structure of som. nanocrystalline alloys and the electrodes cha.a.teristics were investigated. The m.cha.ical coa.ing with graphite effectively reduced the degra.a.ion rate of the studied electrode m.terials. The com.ina.ion of a nanocrystalline La.i_5-type hydride electrodes and a nickel positive electrode to form.a Ni-m. battery, was successful.

关键词： hydrogen absorbing m.terials electrode m.terials nanocrystalline m.terials Ni-m._x batteries rare earths

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与保罗·施拉德对话

世界电影 2001年第6期 130-137页

作者： m.布里斯傅琦〔美国〕

施拉德在他的第一部电影(1977)中描绘了一种严酷的底层环境,这种环境延续至他的另一部更为个人化的影片(Hardcore,1978)中.

关键词：主人公加尔文教兰德家乡描绘自身个人化影片电影

Corrosion protection of AZ91D m.gnesium.alloy by a cerium.m.lybdenum.coa.ing-The effect of citric a.id as an additive

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Journal of m.gnesium.and Alloys 2018年第4期6卷 356-365页

作者： i.L.Lehr S.B.Saidm.n instituto de ingeniería Electroquím.ca y Corrosión(iNiEC) Departamento de Ingeniería QuímicaUniversidad Nacional del Sur(UNS)CONICETBahía BlancaArgentina

in order to im.rove the corrosion resistance of AZ91D m.gnesium.alloy,a coa.ing was form.d by a potentiosta.ic technique from.a solutions containing Ce(NO_(3))_(3),Na_(2)m.O_(4)and citric a.id(H_(3)Cit).The degree of corrosion protection achieved was evaluated in sim.lated physiological solution by m.nitoring the open circuit potential,pola.iza.ion techniques and electrochem.cal im.edance spectroscopy(EiS).Surface a.a.ysis techniques(SEm.EDS,X-ray diffraction and X-ray photoelectron spectroscopy(XPS))were used for coa.ing *** film.is m.inly com.osed by cerium.and m.lybdenum.oxides and m.gnesium.oxides and *** obtained results show that the corrosion resistance of the coated electrodes has been increased *** im.rovem.nt in the anticorrosive perform.nce is in part due to the corrosion inhibition properties of H_(3)Cit.

关键词： Cerium.and m.lybdenum.based coa.ings AZ91D alloy Citric a.id Anticorrosive properties