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Plasma Science and Tech.ology 2008年第3期10卷 278-283页

作者： kh.h.EL-Sh.RBAGY Plasma Ph.sics and Nuclear Fusion Department Nuclear Research Center Atomic Energy Authority Cairo Egypt

Th. effect of a h.gh.frequency （h.） electric field on th. propagation of electrostatic wave in a 2D non-uniform relativistic plasma waveguide is investigated. A variable separation meth.d is applied to th. two-fluid plasma model. An analytical study of th. reflection of electrostatic wave propagation along a magnetized non-uniform relativistic plasma slab subjected to an intense h. electric field is presented and compared with.th. case of a non relativistic plasma. It is found th.t, wh.n th. frequency of th. incident wave is close to th. relativistic electron plasma frequency, th. plasma is less reflective due to th. presence of both.an h. field and th. effect of relativistic electrons. On th. oth.r h.nd, for a low-frequency incident wave th. reflection coefficient is directly proportional to th. amplitude of th. h. field. Also, it is sh.wn th.t th. relativistic electron plasma leads to a decrease in th. value of reflection coefficient in comparison with.th. case of th. non relativistic plasma.

关键词： electrostatic wave relativistic plasma waveguide reflection coefficient separation meth.d

Electrical Ch.racteristics of A1/CNT/NiPc/PEPC/Ag Surface-Type Cell

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Ch.nese Ph.sics Letters 2010年第10期27卷 164-167页

作者： Mutabar Sh.h.kh. S. Karimov Zubair Ah.ad M. h. Sayyad Gh.lam Ish.q khan Institute of Engineering Sciences and Tech.ology Topi-23640 Swabi N.W.F.P Pakistan Ph.sical Tech.ical Institute of Academy of Sciences Rudaki Ave.33 Dushanbe 734025 Tajikistan Department of Mech.nical Engineering University of Auckland 20 Symonds Street Auckland New Zealand

Th. blend of nickel ph.h.locyanine （NiPc）（2 wt. %） poly-N-epoxypropylcarbazole （PEPC）, （1 wt. %） and carbon nano-tube （CNT） powder （2 wt. %） in benzole is deposited by drop-casting on glass substrates with.pre-deposited metallic electrodes to fabricate Ag/CNT/NiPc/PEPC/A1 surface type cell. It is assumed th.t th. h.gh.nonlinearity of th. I — V ch.racteristics is related to deep traps in th. nano-scale depletion region in NiPc th.t is observed experimentally. Th. values of ideality factor and barrier h.igh. are determined from th. I — V curve and th.y are found to be 8.4 and 1.05eV, respectively. Th. values of mobility and conductivity are calculated to be 7.94 × 10？8 cm/Vs and 3.5 × 10？6 Ω？1 cm？1. Th. values of ideality factor and series resistance are also calculated by using Ch.ung＇s functions, wh.ch.are in good agreement with.th. values calculated from th. I — V curve.

关键词： CARBON nanotubes Ph.h.LOCYANINES ELECTRODES SURFACES (Tech.ology) MICROFABRICATION EXPERIMENTAL design

Priming th. seed:h.licobacter pylori alters epith.lial cell invasiveness in early gastric carcinogenesis

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World Journal of Gastrointestinal Oncology 2018年第9期10卷 231-243页

作者： Silvia Molina-Castro Vanessa Ramírez-Mayorga Warner Alpízar-Alpízar Cancer Epidemiology Research.Program Health Research InstituteUniversity of Costa RicaSan José2060Costa Rica Clinical Department School of MedicineUniversity of Costa RicaSan José2060Costa Rica Public Nutrition Section School of NutritionUniversity of Costa RicaSan José2060Costa Rica Center for Research.in Microscopic Structures University of Costa RicaSan José2060Costa Rica Department of Bioch.mistry School of MedicineUniversity of Costa RicaSan José2060Costa Rica

h.licobacter pylori(h. pylori) infection is a wellestablish.d risk factor for th. development of gastric cancer(GC), one of th. most common and deadliest neoplasms worldwide. h. pylori infection induces ch.onic inflammation in th. gastric mucosa th.t, in th. absence of treatment, may progress th.ough.a series of steps to GC. GC is only one of several clinical outcomes associated with.th.s bacterial infection, wh.ch.may be at least partially attributed to th. h.gh.genetic variability of h. pylori. Th. biological mech.nisms underlying h.w and under wh.t circumstances h. pylori alters normal ph.siological processes remain enigmatic. A key aspect of carcinogenesis is th. acquisition of traits th.t equip preneoplastic cells with.th. ability to invade. Accumulating evidence implicates h. pylori in th. manipulation of cellular and molecular programs th.t are crucial for conferring cells with.invasive capabilities. We present h.re an overview of th. main findings about th. involvement of h. pylori in th. acquisition of cell invasive beh.vior, specifically focusing on th. epith.lial-to-mesench.mal transition, ch.nges in cell polarity, and deregulation of molecules th.t control extracellular matrix remodeling.

关键词： h.licobacter pylori Plasminogen activation system Invasion Epith.lial-to-mesench.mal transition

Electrical ch.racterization of th. organic semiconductor Ag/CuPc/Au Sch.ttky diode

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Journal of Semiconductors 2011年第4期32卷 52-56页

作者： Mutabar Sh.h.M.h.Sayyad kh.S.Karimov Gh.lam Ish.q khan Institute of Engineering Sciences and Tech.ology ph.sical Tech.ical Institute of Academy of Sciences

Th.s paper reports on th. fabrication and investigation of a surface-type organic semiconductor copper ph.h.locyanine（CuPc） based diode.A th.n film of CuPc of th.ckness 100 nm was th.rmally sublimed onto a glass substrate with.preliminary deposited metallic electrodes to form a surface-type Ag/CuPc/Au Sch.ttky *** current-voltage ch.racteristics were measured at room temperature under dark *** barrier h.igh. was calculated as 1.05 *** values of mobility and conductivity was found to be 1.74×10;cm;/（V·s） and 5.5×10;Ω;·cm;,*** low voltages th. device sh.wed oh.ic conduction and th. space ch.rge limited current conduction mech.nisms were dominated at h.gh.r voltages.

关键词： Sch.ttky diode copper ph.h.locyanine th.n film organic semiconductor mobility

CuPc based organic-inorganic h.tero-junction with.Au electrodes

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Journal of Semiconductors 2010年第7期31卷 22-25页

作者： Zubair Ah.ad Muh.mmad h.Sayyad kh.S.Karimov Gh.lam Ish.q khan Institute of Engineering Sciences and Tech.ology TopiNWFP23460Pakistan Department of Mech.nical Engineering 20 Symond Street AucklandUniversity of AucklandNew Zealand

A h.tero-junction of n-silicon（n-Si） and copper ph.h.locyanine（CuPc） h.s been *** current -voltage ch.racteristics were investigated to explain th. rectification and conduction *** effect of temperature and h.midity on th. electrical properties of n-Si/CuPc h.tero-junction h.s also been *** ch.racteristics of th. junction h.ve been observed to be temperature and h.midity dependent,so it is suggested th.t th.s junction can be used as a temperature and h.midity sensor.

关键词： inorganic-organic h.tero-junction n-Si CuPc

Effects of magnetic field,porosity,and wall properties for anisotropically elastic multi-stenosis arteries on blood flow ch.racteristics

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Applied Math.matics and Mech.nics(English.Edition) 2011年第8期32卷 1047-1064页

作者： kh.S.MEkhEIMER M.h.h.ROUN M.A.ELKOT Department of Math.matics Faculty of Science Al-Azh.r University Department of Math.matics Faculty of Education Ain Sh.ms University Department of Math.matics Faculty of Science Suez Canal University

A math.matical model for blood flow th.ough.an elastic artery with.multistenosis under th. effect of a magnetic field in a porous medium is presented. Th. considered arterial segment is simulated by an anisotropically elastic cylindrical tube filled with.a viscous incompressible electrically conducting fluid representing blood. An artery with.mild local narrowing in its lumen forming a stenosis is analyzed. Th. effects of arterial wall parameters represent viscoelastic stresses along th. longitudinal and circumferential directions T t and T θ , respectively. Th. degree of anisotropy of th. vessel wall γ, total mass of th. vessel, and surrounding tissues M and contributions of th. viscous and elastic constraints to th. total teth.ring C and K respectively on resistance impedance, wall sh.ar stress distribution, and radial and axial velocities are illustrated. Also, th. effects of th. stenosis sh.pe m, th. constant of permeability κ, th. h.rtmann number h. and th. maximum h.igh. of th. stenosis size δ on th. fluid flow ch.racteristics are investigated. Th. results sh.w th.t th. flow is appreciably influenced by surrounding connective tissues of th. arterial wall motion, and th. degree of anisotropy of th. vessel wall plays an important role in determining th. material of th. artery. Furth.r, th. wall sh.ar stress distribution increases with.increasing T t and γ wh.le decreases with.increasing T θ , M, C, and K. Transmission of th. wall sh.ar stress distribution and resistance impedance at th. wall surface th.ough.a teth.red tube are substantially lower th.n th.se th.ough.a free tube, wh.le th. sh.aring stress distribution at th. stenosis th.oat h.s inverse ch.racteristic th.ough.totally teth.red and free tubes. Th. trapping bolus increases in size toward th. line center of th. tube as th. permeability constant κ increases and decreases with.th. h.rtmann number h. increased. Finally, th. trapping bolus appears, gradually in th. case of non-symmetric stenosis, and disap

关键词： stenosis degree of anisotropy free tube teth.red tube trapping bolus

A Study on th. Wear Beh.viour of Dual Ph.se Steels

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Journal of Materials Science & Tech.ology 2007年第1期23卷 107-110页

作者： V.Abouei h.Sagh.fian Sh.kheirandish.kh.Ranjbar Department of Metallurgy and Materials Engineering Iran University of Science and TechnologyIran Sh.h.d Ch.mran University Iran

Dual ph.se （DP） steels containing four different amounts of martensite ranging from 43 vol. pct to 81 vol. pct h.ve been developed from 0.2 wt pct carbon steel by intercritical h.at treatment at a fixed temperature of 780℃ with.varying h.lding times followed by water quench.ng. Dry sliding wear tests h.ve been conducted on DP steels using a pin- on-disk mach.ne under different normal loads of 61.3, 68.5, 75.7 and 82.6 N and at a constant sliding speed of 1.20 m/s. At th.se loads, th. mech.nism of wear is primarily delamination, wh.ch.h.s been confirmed by SEM micrograph. of subsurface and wear debris of samples. Wear properties h.ve been found to improve with.th. increase in martensite volume fraction in dual ph.se steels.

关键词： Wear Dual ph.se steel Microstructure

Synth.sis of Antipyrine Derivatives Derived from Dimedone

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Ch.nese Journal of Ch.mistry 2007年第4期25卷 570-573页

作者： EIASh.Y E. S. h. AWAD L. F. IBRAh.M E. I. BDEEWY O. kh. Ch.mistry Department Faculty of Science Alexandria University Alexandria Egypt Suez Cannel University lsmailia Egypt

Coupling of dimedone with.th. diazonium salt of 4-aminoantipyrine afforded 2,3-dimeth.l-4-[2-（5,5-dimeth.l- 2,6-dioxocycloh.x-2-ylidend）-h.drazino]-5-oxo-1-ph.nylpyrazoline （3）. Reaction of 3 with.excess ph.nylh.drazine gave th. mixed trish.drazone derivative 4. Treatment of 3 with.h.droxylamine produced th. bisoxime 5 wh.ch.upon deh.drative cyclization with.acetic anh.dride gave th. corrsponding tetrah.drobenzo[d][1,2,3]triazole derivative 7. A one-pot synth.sis of 7 was done by reacting 3 with.h.droxylamine h.droch.oride in pyridine, followed by h.atment with.acetic anh.dride.

关键词： dimedone antipyrine 1,2,3-triazole ph.nylh.drazone

Influence of monovalent cations and CuO nanoparticles on X-nanozeolite in uranium anionic species separation from contaminated drinking water

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Ch.nese Journal of Ch.mical Engineering 2017年第6期25卷 782-792页

作者： h.R. Sh.kur kh. Rezaee Ebrah.m Saraee M.R. Abdi G. Azimi Department of Nuclear Engineering Faculty of Advance Sciences and Technologies University of lsfahan Isfahan 81746-73441 lran Department of Ph.sics Faculty of science University of lsfahan lsfahan 81747-73441 Iran Department of Ch.mistry University of lsfahan lsfahan 81747-73441 Iran

Th. main purpose of th.s work was th. modification of NaX nanozeolite using copper oxide nanoparticles and various monovalent cations such.as K^+, Cs^+, and Ag^+in order to make th. negatively ch.rged zeolite surface accessible for anionic forms of uranium wh.ch.are th. most dominant species of uranium in th. contaminated radioactive waters at natural p h. Various meth.ds such.as th. X-ray fluorescence(XRF), X-ray powder diffraction(XRD), field emission scanning electron microscopy(FE-SEM), transmission electron microscopy(TEM), Fourier transform infrared spectroscopy(FT-IR), and atomic absorption spectroscopy(AAS) were used to ch.racterize th. final synth.sized absorbents. Batch.tech.ique was used to study th. adsorption beh.vior of uranium ions from polluted drinking water by Na X nanozeolite and its modified forms. In order to better understand th. performance of th.m, th. results were compared with.th.se th.t were obtained for synth.sizing bulk NaX zeolite and Na-form of clinoptilolite natural zeolite. Preliminary results indicated th.t uranium sorption increased as th. loading level of CuO nanoparticles on NaX nanozeolite increased from 2.1 wt% to 11.2 wt%. In addition,from th. obtained data, an increase in uranium removal efficiency resulted as ch.rge/ionic radius ratio of exch.nged cation decreased. Also, th. effect of contact time, solid–liquid ratio, initial concentration and temperature on th. adsorption process was studied. It is worth.mentioning th.t, in th.s study, th. sorption of uranium was performed under natural conditions of ph.and th. presence of competing cations and anions wh.ch.are available in drinking waters.

关键词： Zeolite Monovalent cation NaX/CuO nanocomposite Uranium anions Separation Waste water

Removing contaminants from tannery wastewater by ch.mical precipitation using CaO and Ca(Oh.2

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Ch.nese Journal of Ch.mical Engineering 2020年第4期28卷 1107-1111页

作者： Adriana Reyes-Serrano Joel ELópez-Alejo Manuel Ah.rnández-Cortázar Ignacio Elizalde Instituto Politécnico Nacional Centro Mexicano para la Producción más LimpiaCiudad de México 07340Mexico

Th. removal of Cr,sulfates and Ch.mical Oxygen Demand(COD)from industrial tannery wastewater by ch.mical precipitation was carried out using Calcium oxide(CaO)and Calcium h.droxide(Ca(Oh.2).Different doses of alkalis,ranging from deficiency to excess h.droxyl species over th. stoich.ometric necessary,were used to remove th.oretically th. 100%of Cr[0.3-3.2 g alkali·(g Cr^3+)^-1].Th. precipitation was carried out at room temperature,10 min of vigorous stirring,200 r·min^-1 and a settling time of 24 h.followed by separation and ch.racterization of liquid *** result of addition of alkalis,ph.underwent increase as did th. alkali *** removal of Cr,and sulfates also increased as alkali concentration did,alth.ugh.for first species th. ch.nges at h.gh.r alkali contents were less *** removal on th. oth.r h.nd,did not follow a unique trend,instead exh.bited a *** on our results,selection of a specific dose of alkali was carried out taking as reference th. efficiency on total ch.omium removal,keeping th. ph.in th. range 7 to 9 to ensure Cr precipitation as ch.omium *** th.se conditions,jar test was used to produce enough.liquid product in order to determine th. removal percent of several oth.r *** removal percent of th. species was as follows:Cr,SO4^2-,ZnSO4,FeSO4,CN^-1,NiSO4,Fe2[Fe(CN)6]at 99.8%,66.9%,99.6%,21.4%,70.9%,52.8%and 76.4%with.CaO,and 99.8%,61.6%,99.9%,7.1%,84.0%,54.4%and 90.5%with.Ca(Oh.2,respectively.

关键词： Tannery wastewater Alkali Removal Ch.omium Sulfates Synergistic effect