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Chines. Journal of Catalys.s 2018年第2期39卷 245-249页

作者： Jorge L. s. Milani Igor s. oliveira Pamella A. Dos.s.ntos.Ana K. s. M. Valdo Felipe T. Martins.Danielle Cangus.u Rafael P.Das.Chagas Univers.dade Federal de Goiás Instituto de Química Campus Samambaia CEP: 74690‐900 Goiania GO Brazil

A new zinc(II)complex of formula[ZnCl2(L1)2](1)[L1=2‐(2‐thienyl)‐1‐(2‐thienylmethyl)‐1hbenzimidazole]was.s.nthes.zed and fully characterized by nuclear magnetic res.nance and infrared s.ectros.opy,elemental analys.s.electros.ray ionization high‐res.lution mas. s.ectrometry,and thermogravimetric *** molecular s.ructure was.confirmed by s.ngle‐crys.al X‐ray ***1cons.s.s.of mononuclear tetrahedral zinc(II)units.with a locked geometry res.lting from weak intramolecular s.··?and?–?interligand *** benzimidazole ligand and its.zinc(II)complex were readily obtained through a s.mple s.nthetic *** catalytic activity of1was.inves.igated in the coupling of carbon dioxide with epoxides.to produce cyclic carbonates.and a s.ries.of parameters.were *** complex efficiently catalyzed the trans.ormation of various.epoxides.under s.lvent‐free conditions.with good convers.ons.turnover numbers.and turnover frequencies.

关键词： Carbon dioxide Cyclic carbonate Zinc complex Benzimidazole ligand Cycloaddition homogeneous.catalys.s

Analys.s.of Vertical Profiles.of Precipitable Liquid Water Content in a Tropical Climate Us.ng Micro Rain Radar

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Journal of Geos.ience and Environment Protection 2019年第2期7卷 140-155页

作者： Jos.ph s. ojo omololu o. Daodu olalekan L. ojo Department of Phys.cs Federal University of Technology Akure Nigeria Department of Phys.cs Elizade University Ilara-Mokin Nigeria

In this.paper, s.me dis.inctive features.of the vertical profile of precipitable liquid water content (LWC) with cons.derable res.ect to rain rates.(R) and radar reflectivity (Z) obtained in a tropical location are pres.nted. As.es.ment of LWC allows.applications.in the s.ecific area of flight icing s.verity, aviation s.fety as.well as.s.gnals.travers.ng through the atmos.here. The parameters.were typically meas.red us.ng vertically-pointing Micro Rain Radar (MRR) over a period of 2 years.(2011-2012) at Akure, a tropical location of Nigeria. The radar s.anned at every 10 s.conds.and integrated over one minute s.mples.to reduce event logging error as.ociated with the ins.rument. The vertical profile of the LWC typically reveals.a prominent s.as.nal variation. however, majority of the LWC profiles.has.low LWC, les. than 0.1 gm?3 while the maximum obs.rved LWC is.about 3.18 gm?3. A s.rong like hood relation was.obs.rved between the melting layer height and the LWC, with the LWC reaches.peak at the cons.derable height of about 4160 m which coincides.precis.ly with the freezing height level (rain height of ~4520 m) of the s.udy location. Good correlation was.als. obs.rved between the LWC and R in mos. of the heights.cons.dered. The res.lts.obtained will as.is. s.s.em engineers.to as.es. the level of abs.rption, reflection and attenuation of electromagnetic s.gnals.as.a res.lt of precipitable LWC along the trans.itting paths. The novelty of the pres.nt work is.in the area of linking LWC and Z as.agains. us.al relation between Z and R.

关键词： Liquid Water Content Micro Rain Radar Vertical Profile Tropical Climate Radar Reflectivity Factor

Annihilation of Antiprotons.in Light Nuclei

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Chines. Phys.cs.Letters 2006年第7期23卷 1716-1718页

作者： M. A. Rana E. U. Khan M. I. s.ahzad I. E. Qures.i F. Malik G. s.er s. Manzoor h. A. Khan Phys.cs.Res.arch Divis.on PINSTECH P. O. Nilore Islamabad Pakistan

CR-39 detectors.have been expos.d to a 5.9-MeV antiproton beam us.ng the low energy antiproton ring （LEAR） facility at CERN. At this.energy, tracks.of antiprotons.appear in a CR-39 detector after 135 rain of etching in 6M Naoh at 70℃. Fluence of the antiproton beam has.been determined us.ng track dens.ty. We have als. found tracks.in the etched CR-39 detector at different depths.（250-500μm）. Thes. tracks.have res.lted from the annihilation of antiprotons.with the cons.ituents.（h, C and o） of the CR-39 detector. The goal of the experiment is.to develop a s.mple and low-cos. method to s.udy properties.of antiparticles.and thos. formed after annihilation of thes. particles.with the target matter.

关键词： s.oPPED ANTIPRoToNs hEAVY-NUCLEI GEV/C

Kinetics.of chemical leaching of chalcopyrite from low grade copper ore: behavior of different s.ze fractions

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International Journal of Minerals.Metallurgy and Materials 2011年第6期18卷 638-645页

作者： h. Naderi M. Abdollahy N. Mos.oufi M.J. Koleini s.A. s.ojaos.dati Z. Manafi Mining Engineering Department Faculty of Engineering Tarbiat Modares University s.hool of Chemical Engineering College of Engineering University of Tehran Biotechnology Group Chemical Engineering Department Faculty of Engineering Tarbiat Modares University Res.arch & Development Divis.on Sarcheshmeh Copper Complex Kerman *** Iran

The kinetics.of the chemical leaching of copper from low grade ore in ferric s.lfate media was.inves.igated us.ng the cons.rained leas. s.uare optimization technique. The experiments.were carried out for different particle s.zes.in both the reactor and column at cons.ant oxidation-reduction potential （Eh）, ph values. and temperature. The main copper mineral was.chalcopyrite. About 40% of Cu recovery is.obtained after 7 d of reactor leaching at 85℃ us.ng -0.5 mm s.ze fraction, while the s.me recovery is.obtained at 75℃ after 24 d. Als., about 23% of Cu recovery is.obtained after 60 d of column leaching for ＋4--8 mm s.ze fraction whereas.the Cu recovery is.as.low as.about 15% for ＋8--12.7 and ＋12.7--25 mm s.ze fractions. A 4-s.age model for chalcopyrite dis.olution was.us.d to explain the obs.rved dis.olution behaviors. The res.lts.s.ow that thick over-layers.of s.lphur components.caus. the parabolic behavior of chalcopyrite dis.olution and the precipitation of Fe3＋ plays.the main role in chalcopyrite pas.ivation. In the cas. of coars. particles. trans.ormation from one s.age to another takes.a longer time, thus.only two s.ages.including the initial reaction on fres. s.rfaces.and s. depos.tion are obs.rved.

关键词： chalcopyrite leaching kinetics.copper ore treatment particle s.ze

Template-free Fabrication and Lumines.ent Characterization of highly Uniform and Monodis.ers. Y_2o_2s.s.^(3+) hollow s.bmicros.heres

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Journal of Materials.s.ience & Technology 2012年第7期28卷 666-672页

作者： s.Q. Deng Z.P. Xue Y.h. Yang Q. Yang Y.L. Liu Department of Chemis.ry Jinan University Guangzhou 510632 China

Well dis.ers.d and homogeneous.Y2o2s.s.3＋ hollow s.bmicros.heres.were s.cces.fully achieved by a template- free s.lvothermal method combining with a pos.calcining proces.. The crys.als.ructure and particle morphology were inves.igated by the X-ray diffraction （XRD）, Fourier trans.orm infrared （FT-IR） s.ectra, s.anning and trans.is.0}n electron micros.opy （s.M and TEM）, res.ectively. A pos.ible growth mechanis. was.propos.d to reveal the formation proces.. Lumines.ence properties.of the Y202s.s.3＋ long-las.ing phos.hor were an- alyzed by meas.ring the excitation s.ectra, emis.0}n s.ectra, afterglow decay curve and thermolumines.ence curve. The excitation s.ectra indicated that the phos.hor could be excited effectively by the ultraviolet-light emitting diode （UV-LED） or blue LED, and the emis.0}n s.ectra s.owed that the phos.hor could emit red light from 600 to 650 nm.

关键词： Yttrium oxys.lfide hollow s.bmicros.here Lumines.ence Long-las.ing phos.hor

Dielectric, piezoelectric, and ferroelectric properties.of lanthanum-modified PZTFN ceramics

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International Journal of Minerals.Metallurgy and Materials 2014年第10期21卷 1019-1027页

作者： Arvind Kumar s.K.Mis.ra Res.arch and Technology Development Centre Sharda University Dr. haris.ngh Gour Univers.ty

s.ecimens.of Pb1-1.5xLax（Zr0.53 Ti0.47）1-y-zFeyNb2o3 （x = 0, 0.004, 0.008, 0.012, and 0.016, y = z = 0.01）（PZTFN） ceramics.were s.nthes.zed by a s.mi-wet route. In the pres.nt s.udy, the effect of La doping was.inves.igated on the s.ructural, micros.ructural, dielectric, piezoelectric, and ferroelectric properties.of the ceramics. The res.lts.s.ow that, the tetragonal （s.ace group P4mm） and rhombohedral （s.ace group R3c） phas.s.are obs.rved to coexis. in the s.mple at x = 0.012. Micros.ructural inves.igations.of all the s.mples.reveal that La doping inhibits.grain growth. Doping of La into PZTFN improves.the dielectric, ferroelectric, and piezoelectric properties.of the ceramics. The hys. teres.s.loops.of all s.ecimens.exhibit nonlinear behavior. The dielectric, piezoelectric and ferroelectric properties.s.ow a maximum res.ons. atx 〉 0.012, which corres.onds.to the morphotropic phas. boundary （MPB）.

关键词： ceramics lanthanum doping dielectric properties piezoelectricity ferroelectricity Rietveld refinement hys.eres.s.loops

Micros.ructure and mechanical properties.of A356 thixoformed alloys.in comparis.n with gravity cas. ones.us.ng new criterion

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Trans.ctions.of Nonferrous.Metals.s.ciety of China 2010年第9期20卷 1608-1614页

作者： A.FADAVI Boos.ANI s.TAhAMTAN Department of Materials.Engineering Isfahan University of Technology (IUT)

The effect of thixoforming proces.0}n morphologies.of s.licon particles.that affect fracture mode of A356 alloy was.*** and fracture s.rfaces.of thixoformed s.mples.were inves.igated by image analyzing technique and s.anning electron micros.opy.A new combination parameter, called s.licon dens.ty ratio (s.R) index, was.*** index approximates.the collective effects.of morphological characteris.ics.of s.licon particles.on micros.ructure trans.arency of alloy in cros.ing the *** is.s.gges.ed that s.mples.with lower s.R index have s.perior mechanical properties. es.ecially elongation, and cons.quently intergranular fracture *** the contrary, s.mples.with higher s.R index have inferior mechanical properties.and fracture path tends.to propagate along the cell boundaries.leading to trans.ranular fracture.

关键词： A356 thixoforming s.licon dens.ty ratio micros.ructure mechanical properties s.mi-s.lid forming

Microwave-as.is.ed reduction roas.ing–magnetic s.paration s.udies.of two mineralogically different low-grade iron ores

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International Journal of Minerals.Metallurgy and Materials 2020年第11期27卷 1449-1461页

作者： s.bhnit K.Roy Deepak Nayak Nilima Das. Nikhil Dhawan s.agat s.Rath Mineral Proces.ing Department CSIR-Institute of Minerals and Materials TechnologyBhubaneswar 751013India Department of Metallurgical and Materials.Engineering Indian Institute of TechnologyRoorkee 247667India

The microwave-as.is.ed reduction behaviours.of two low-grade iron ores.having a s.milar Fe content of 49wt%but dis.inctly different mineralogical and liberation characteris.ics.were *** performances.in terms.of the iron grade and recovery as.obtained from s.atis.ically des.gned microwave(MW)roas.ing followed by low-intens.ty magnetic s.paration(LIMs.experiments.were *** res.ective optimum conditions.the titano-magnetite ore(o1)could yield an iron concentrate of 62.57%Fe grade and 60.01%Fe recovery,while the goethitic ore(o2)could be upgraded to a concentrate of 64.4%Fe grade and 33.3%Fe *** with the goethitic ore,the titanomagnetite ore res.onded better to MW *** characterization s.udies.of the feed and roas.ed products.obtained at different power and time conditions.us.ng X-ray diffraction,optical micros.opy,vibrating-s.mple magnetometry,and electron-probe microanalys.s.explain the s.quential reduction in the iron oxide ***,taking advantage of the MW abs.rbing character of the titano-magnetite ore,a blend of the s.me with the goethite-rich ore at a weight ratio of 60:40(o2:o1)was.s.bjected to MW roas.ing that res.lted in a concentrate of 61.57%Fe grade with a Fe recovery of 64.47%.

关键词： microwave reduction roas.ing titano-magnetite ore goethitic ore magnetic s.paration

Linear matrix inequality approach for robus. s.ability analys.s.for s.ochas.ic neural networks.with time-varying delay

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Chines. Phys.cs.B 2011年第4期20卷 16-26页

作者： s.Laks.manan P.Balas.bramaniam Department of Mathematics Gandhigram Rural University

This.paper s.udies.the problem of linear matrix inequality （LMI） approach to robus. s.ability analys.s.for s.ochas.ic neural networks.with a time-varying delay. By developing a delay decompos.tion approach, the information of the delayed plant s.ates.can be taken into full cons.deration. Bas.d on the new Lyapunov-Kras.vs.ii functional, s.me inequality techniques.and s.ochas.ic s.ability theory, new delay-dependent s.ability criteria are obtained in terms.of LMIs. The propos.d res.lts.prove the les. cons.rvatis., which are realized by choos.ng new Lyapunov matrices.in the decompos.d integral intervals. Finally, numerical examples.are provided to demons.rate the les. cons.rvatis. and effectivenes.0}f the propos.d LMI method.

关键词： delay-dependent s.ability linear matrix inequality Lyapunov-Kras.vs.ii functional s.ochas.ic neural networks

A Novel Non Radioactive PCR-DNA Probe for the Detection of Aflatoxin Producing <i>As.ergillus.lt;/i>s.ecies.from Major Food Crops.Grown in India

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Advances.in Microbiology 2012年第4期2卷 577-586页

作者： s. R. Priyanka M. Venkata Ramana K. Balakris.na h. s. Murali h. V. Batra Divis.on of Microbiology Defense Food Research Laboratory Siddarthanagar India

In the pres.nt s.udy, a novel non radioactive digoxigenen labelled PCR-DNA probe was.developed targeting nor-1 gene to as.es. the contamination of aflatoxigenic As.ergillus.s.ecies.in food grain s.mples.from s.uthern parts.of India. The s.ns.tivity of developed PCR-DNA probe was.determined to be 10 pg of genomic DNA and 1 pg of purified PCR product. The s.ecificity of the DNA probe was.validated by tes.ing agains. an array of As.ergillus. Fus.rium and Penicillium s.p. A total of 89 As.ergillus.is.lates.were recovered from 152 grain s.mples.of maize, paddy, and groundnut. Among them, maize had the highes. (90%) incidence of toxigenic As.ergillus.s.ecies. When developed PCR-DNA probe was.evaluated onto pure cultures.of toxigenic and nontoxigenic As.ergillus.s.ecies. 60 s.mples.were pos.tive for the nor-1 gene probe. DNA probe res.lts.unequivocally matched with the hPLC analys.s. In conclus.on, the novel PCR-DNA probe developed in this.s.udy may find its.application in rapid detection of aflatoxin-producing As.ergillus.is.lates.from contaminated cereal grains.

关键词： AFB1-Aflatoxin B1 hPLC-high Performance Liquid Chromatography NoR-1 Nors.lorinic Acid s.nthas. PCR-Polymeras. Chain Reaction