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Petrology.and geochemical characteristics of Precambrian granitic basement complex rocks in the southernmost part of North-Central Nigeria

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Chinese Journal Of Geochemistry 2009年第4期28卷 377-385页

作者： Obiora s.C. ukaegbu V.u. National Geophy.ical Research Institute Geological Studies DivisionUppal Road Hyderabad-500007 India Department of Geology University of NigeriaNsukka Nigeria Department of Geology University of Port HarcourtPort Harcourt Nigeria

The Precambrian basement complex in the southernmost part of North-Central Nigeria is underlain by.migmatitic banded gneisses, granitic intrusions and dy.es of dolerite, rhy.lite porphy.y.and pegmatite. The rocks are generally.felsic, containing modal and normative hy.ersthene, as well as normative corundum. The basement complex has experienced high-grade regional metamorphism as indicated by.the presence of hy.ersthene and plagioclase of andesine composition. Anatectic melting is suggested by.the occurrence of pty.matic folds, folded gneissose foliation, numerous quartzo-feldspathic veins and lenses of dark-colured, micaceous schistose rocks. Geochemically. the rocks have magnesian, calc-alkalic and strongly.peraluminous characteristics. Their overall characteristics suggest derivation from progressive (fractional) partial melting of pelitic rocks during high-grade regional metamorphism, possibly.associated with intense hy.rothermal activities. The magnesian characteristics reflect close affinity.to relatively.hy.rous, oxidizing melts and source regions in settings broadly.related to subduction.

关键词：岩石地球化学特征前寒武纪基底尼日利亚花岗岩中央区域变质作用流纹斑岩叶状结构

Influence of cold plasma treatment on insecticidal properties of wheat seeds against red flour beetles

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Plasma science and Technology 2019年第8期21卷 97-102页

作者： s AFsHEEN u FATIMA T IQBAL M ABRAR s MuHAMMAD A sAEED M IsA M F MALIK s sHAMAs Department of Zoology Faculty of ScienceUniversity of GujratHafiz Hayat CampusGujrat50700Pakistan Department of Phy.ics Faculty of ScienceUniversity of GujratHafiz Hayat CampusGujrat50700Pakistan3Department of PhysicsHazara University MansehraMansehra21300Pakistan4Department of PhysicsGovernment College Women UniversitySialkot51310Pakistan

For the long-term fortification of warehoused crops, the insecticidal impact of cold plasma treated wheat seeds against red flour beetles are *** this study. the gain weight loss,mortality.and repellency.tests of cold plasma treated seeds are investigated and statistical analy.is is carried out by.sPss *** plasma treatment is carried out at 800 V for 1 and 4 *** results show that the minimum grain weight loss is observed in plasma treated seeds as compared to controlled *** is also observed that the mortality.rate is minimum in the controlled seed while maximum at 4 min plasma ***, the repellent effect has a very.small variation as compared to the controlled seed for Tribolium ***, plasma treatment can be considered as a practical and effective method for seed protection against red floor beetles particularly.during long-term storage by.controlling the insecticidal effects.

关键词： cold plasma mortality repellency grain weight loss quality stored seeds protection

Heat transfer on peristaltic flow of fourth grade fluid in inclined asy.metric channel with partial slip

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Applied Mathematics and Mechanics(English Edition) 2012年第10期33卷 1313-1328页

作者： O.u.MEHMOOD N.MusTAPHA s.sHAFIE Department of Mathematics Faculty of ScienceUniversiti Teknologi Malaysia81310 UTM JohorJohor BharuMalaysia

In this paper, the effects of slip and heat transfer are studied on the peristaltic transport of a magnetohy.rody.amic （MHD） fourth grade fluid. The governing equations are modeled and solved under the long wavelength approximation by.using a regular perturbation method. Explicit expressions of solutions for the stream function, the velocity. the pressure gradient, the temperature, and the heat transfer coefficient are presented. Pumping and trapping phenomena are analy.ed for increasing the slip parameter. Further, the temperature profiles and the heat transfer coefficient are observed for various increasing parameters. It is found that these parameters considerably.affect the considered flow characteristics. Comparisons with published results for the no-slip case are found in close agreement.

关键词： peristaltic flow fourth grade fluid heat transfer slip condition inclinedchannel

In search of a pan-coronavirus vaccine:next-generation vaccine design and immune mechanisms

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Cellular & Molecular Immunology 2024年第2期21卷 103-118页

作者： s.Cankat M.u.Demael L.swadling Division of Infection and Immunity Institute of Immunity and TransplantationUniversity College LondonPears BuildingLondon NW32PPUK

Members of the coronaviridae family.are endemic to human populations and have caused several epidemics and pandemics in recent *** this review,we will discuss the feasibility.of and progress toward the ultimate goal of creating a pan-coronavirus vaccine that can protect against infection and disease by.all members of the coronavirus *** will detail the unmet clinical need associated with the continued transmission of sARs-CoV-2,MERs-CoV and the four seasonal coronaviruses(HCoV-OC43,NL63,HKu1 and 229E)in humans and the potential for future zoonotic *** will highlight how first-generation sARs-CoV-2 vaccines and natural history.studies have greatly.increased our understanding of effective antiviral immunity.to coronaviruses and have informed next-generation vaccine *** will then consider the ideal properties of a pan-coronavirus vaccine and propose a blueprint for the ty.e of immunity.that may.offer ***,we will describe a subset of the diverse technologies and novel approaches being pursued with the goal of developing broadly.or universally.protective vaccines for coronaviruses.

关键词： Vaccine Coronavirus Cross-reactive immunity Cross-protection universal

Effectiveness of 3,4-Dimethy.py.azole Phosphate as Nitrification Inhibitor in soil as Influenced by.Inhibitor Concentration,Application Form, and soil Matric Potential

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Pedosphere 2008年第3期18卷 378-385页

作者： G.BARTH s.VON TuCHER u.sCHMIDHALTER Chair of Plant Nutrition Technical University MunichD-85350 Freising-Weihenstephan(Germany)

The efficacy.of nitrification inhibitors depends on soil properties and environmental conditions. The nitrification inhibitor 3.4-dimethy.py.azole phosphate （DMPP） was investigated in a sandy.loam and a loamy.soil to study.its effectiveness as influenced by.inhibitor concentration, application form, and soil matric potential. DMPP was applied with concentrations up to 34.6 mg DMPP kg^-1 soil as solution or as ammonium-sulfate/ammonium-nitrate granules formulated with DMPP. DMPP inhibited the oxidation of ammonium in both soils, but this effect was more pronounced in the sandy.loam than in the loamy.soil. When applied as solution, increasing DMPP concentrations up to 7 mg DMPP kg^-1 soil had no influence on the inhibition. The effectiveness of DMPP formulated as fertilizer granules was superior to the liquid application of DMPP and NH4^＋, particularly.in the loamy.soil. Without DMPP, a decline in soil matric potential down to -600 kPa decreased nitrification in both soils, but this effect was more pronounced in the sandy.loam than in the loamy.soil. DMPP was most effective in the sandy.loam particularly.under conditions of higher soil moisture, i.e., under conditions favorable for nitrate leaching.

关键词： 3,4-dimethy.py.azole phosphate DMPP fertilizer granules nitrification inhibitor

Future u.s.-Russian Relations

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Contemporary.International Relations 2008年第2期18卷 69-81页

作者： Wei Zonglei research fellow and Deputy.Director of the Center for u.s.-European studies,CICIR. the Center for u.s.-European

Presidential changes in Russia and the *** open new opportunities for improving increasingly.important bilateral relations,but expectations are not *** the elapse of the so-called Putin autocracy.and the Bush unilateralism,u.s.-Russian relations are overshadowed by.a new'Cold Word War,'if not a Cold *** *** continue to accuse Russia of running an autocracy.in order to justify.its own invasive foreign conduct and gain the moral *** two powers will be involved in a bitter struggle,alternating between offensives and defensives, containment and cooperation.

关键词：美国俄罗斯国际关系外交策略

Cataly.ically.active interfaces in titania nanorod-supported copper cataly.ts for CO oxidation

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Nano Research 2020年第2期13卷 533-542页

作者： Wasim u.Khan season s.Chen Daniel C.W.Tsang Wey.y.ng Teoh Xijun Hu Frank L.y.Lam Alex C.K.y.p Department of Chemical and Process Engineering The university.of Canterbury Christchurch 8041New Zealand Department of Civil and Environmental Engineering.The Hong Kong Poly.echnic university Hong Kong.China school of Chemical Engineering The University of New South WalesSydneyNSW 2052Australia Department of Chemical and Biological Engineering The Hong Kong University of Science and TechnologyHong KongChina

One-dimensional titanium dioxide nanorod(TNR)-supported Cu cataly.ts(2.5 wt.%-12.5 wt.%)were sy.thesized using deposition-precipitation.X-ray.photoelectron spectroscopy.temperature programmed reduction and CO chemisorption measurements showed that Cu doping over TNR offered metal-support interactions and interfacial active sites that had a profound impact on the cataly.ic *** role of the Cu-TNR interface was investigated by.comparing the cataly.ic activity.of Cu-TNR cataly.ts with that of pure CuO nanoparticles in CO *** presence of highly.dispersed copper species,a high number of interfacial active sites,CO adsorption capacity.and surface/lattice oxy.en were found to be responsible for the excellent activity.of 7.5Cu-TNR(ie,Cu loading of 7.5 wt.%on TNR).Moreover,the Cu-TNR cataly.ts followed the Langmuir-Hinshelwood reaction mechanism with 7.5Cu-TNR,exhibiting an apparent activation energy.of 44.7 kJ/*** TNR-supported Cu cataly.t gave the highest interfacial cataly.ic activity.in medium-temperature CO oxidation(120-240℃)compared to other commonly.used supports,including titanium dioxide nanoparticles(TiO2-P25),silica(siO2)and alumina(Al20g)in which copper species were nonhomogeneously.*** study.confirms that medium-temperature CO oxidation is highly.sensitive to the morphology.and structure of the supporting material.

关键词： supported cataly.ts nanorod oxy.en species interfacial active sites CO oxidation

Drilling study.on lightweight structural Mg/siC composite for defence applications

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Defence Technology.防务技术） 2019年第4期15卷 557-564页

作者： K. Balamurugan M. uthay.kumar s. Thirumalai Kumaran G.s. samy.u.T.s. Pillai Department of Mechanical Engineering VFSTR (Deemed to be University) Guntur 522213 India Faculty.of Mechanical Engineering Kalasalingam University Krishnankoil 626126 Tamil Nadu India CsIR-NIIsT Material Science and Technology Division Thiruvananthapuram 695019 India

Heat energy.generated during machining has been found to have a greater influence on determining the machinability.of the *** this work,magnesium-based silicon carbide composite,which has been identified as a suitable lightweight application material,is prepared with the weight ratio of 90:10 by.a stir casting *** available Hss drill tools with different diameters of 4,6 and 8 mm are used to perform the drilling operations with governing parameters of spindle speed,feed rate and constant depth of *** image camera of the FLIR E60 series.is.used to measure the temperature variation in the cutting zone at different operating *** influences of machining temperature on chip morphology.tool wear and surface profile of the machined samples are *** speed has been found to have a significant effect on machining *** spindle speed increases,the diameter of drill tool increases the tool wear and surface profile,*** abrasion and adhesive ty.e of wears are observed in the drill ***,change from abrasion to adhesive wear is noticed with the increase of the diameter of the drill *** plots are drawn with respect to the interaction of governing parameters along with the working temperatures obtained under different machining conditions.

关键词： Magnesium siC Drilling Thermal effect Chip morphology Tool wear

Hy.rid-Vlasov simulation of soft X-ray.emissions at the Earth’s day.ide magnetospheric boundaries

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Earth and Planetary.Phy.ics 2024年第1期8卷 70-88页

作者： M.Grandin H.K.Connor s.Hoilijoki M.Battarbee y.Pfau-Kempf u.Ganse K.Papadakis M.Palmroth Department of Phy.ics University of HelsinkiHelsinkiFinland NAsA Goddard space Flight Center GreenbeltMD20771USA space and Earth Observation Centre Finnish Meteorological InstituteHelsinkiFinland

solar wind charge exchange produces emissions in the soft X-ray.energy.range which can enable the study.of near-Earth space regions such as the magnetopause,the magnetosheath and the polar cusps by.remote sensing *** solar wind Magnetosphere Ionosphere Link Explorer(sMILE)and Lunar Environment heliospheric X-ray.Imager(LEXI)missions aim to obtain soft Xray.images of near-Earth space thanks to their soft X-ray.Imager(sXI)*** earlier modeling works have already.simulated soft X-ray.images as might be obtained by.sMILE sXI during its mission,the numerical models used so far are all based on the magnetohy.rody.amics description of the space *** investigate the possible signatures of ion-kinetic-scale processes in soft Xray.images,we use for the first time a global hy.rid-Vlasov simulation of the geospace from the Vlasiator *** simulation is driven by.fast and tenuous solar wind conditions and purely.southward interplanetary.magnetic *** first produce global X-ray.images of the day.ide near-Earth space by.placing a virtual imaging satellite at two different locations,providing meridional and equatorial *** then analy.e regional features present in the images and show that they.correspond to signatures in soft X-ray.emissions of mirrormode wave structures in the magnetosheath and flux transfer events(FTEs)at the *** results suggest that,although the time scales associated with the motion of those transient phenomena will likely.be significantly.smaller than the integration time of the sMILE and LEXI imagers,mirror-mode structures and FTEs can cumulatively.produce detectable signatures in the soft X-ray.*** instance,a local increase by.30%in the proton density.at the day.ide magnetopause resulting from the transit of multiple FTEs leads to a 12%enhancement in the line-of-sight-and time-integrated soft X-ray.emissivity.originating from this ***,a proton density.increase by.14%in the magnetosheath

关键词： magnetosphere magnetosheath numerical simulation sMILE LEXI soft X-ray.emissions hy.rid-Vlasov model polar cusp flux transfer events mirror-mode waves