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major,trace element and Sr-Nd isotope evidence for a sublithospheric mantle source for the Umkondo large igneous province

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Geoscience Frontiers 2024年第1期15卷 263-285页

作者： Ben Hayes Lewis D.Ashwal Khulekani B.Khumalo Linda m.Iaccheri School of Geosciences University of the WitwatersrandJohannesburg2050South Africa

the mesoproterozoic(1.11 Ga)Umkondo large igneous province(LIP)in southern Africa and Antarctica was emplaced in<5 myr and is dominated by low-Ti tholeiitic doleritic-gabbroic *** is of particular interest because it ... 详细信息

the mesoproterozoic(1.11 Ga)Umkondo large igneous province(LIP)in southern Africa and Antarctica was emplaced inmyr and is dominated by low-Ti tholeiitic doleritic-gabbroic *** is of particular interest because it is the least studied LIP in southern Africa with both sublithospheric and lithospheric mantle sources proposed and it coincides with the early assembly of Rodinia,so it has importance in understanding the nature of magmatism and tectonics in and around the Kalahari craton during the *** this study,we compiled a large database of existing(~750)and new(~100)major and trace element data for the Umkondo province,as well as 42 new Sr-Nd isotopic measurements,to provide constraints on its magma sources and geochemical *** element compositional variations in the low-Ti tholeiites are explained by low-pressure(1 kbar)three-phase fractional crystallisation(olivine,clinopyroxene and plagioclase)of a parent magma with~10 wt.%mgO in oxidising conditions(QFm+1).Inverse models show that the low-Ti tholeiitic magmas were derived as residual melts after the crystallization of 12%-33%olivine from primary komatiitic-basaltic magmas(up to~20 wt.%mgO)in equilibrium with mantle olivine(Fo90).Low sm/Yb and TiO2/Yb-Nb/Yb indicate that the primary magmas were derived by 2%-20%shallow(40-50 km)partial melting of spinel *** sm/Yb is restricted to dyke swarms and may imply limited magma production from deeper(up to~70 km)garnet lherzolite-like *** low-Ti tholeiites of the Umkondo province are enriched in large ion lithophile elements(Rb-Sr-Cs-K)and depleted in high-field strength elements(Zr-Hf-Nb-Ta),indicating the involvement of crustal material and/or the subcontinental lithospheric *** is supported by covariations in th/Nb,Nb/Yb,Nb/La and Ce/sm with generally negativeΔ***-Nd isotopes lend support to the notion that the Umkondo magmas were derived from depleted and/or enriched sublithospheric mantle sources and subs

关键词： Umkondo large igneous province Low-Ti magma Continental tholeiites Sublithospheric mantle sources Kalahari craton Rodinia

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Anthrax:an update

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Asian Pacific Journal of Tropical Biomedicine 2011年第6期1卷 496-501页

作者： Kamal sm Rashid AKm m Bakar mA Aliad mA Department of medicine Khulna Medical College Department of Paediatrics Khulna Medical College Department of Gastroenterology khulna Medical College

Anthrax is a zoonotic disease caused by Bacillus *** is potentially fatal and highly contagious *** arc the natural *** acquire the disease incidentally by contact with infected animal or animal *** the 18th century an epidemic destroyed approximately half of the sheep in *** 1900 human inhalational anthrax occured sporadically in the United *** 1979 an outbreak of human anthrax occured in Sverdlovsk of Soviet *** continued to represent a world wide *** incidence of the disease has decreased in developed countries as a result of vaccination and improved industrial *** anthrax clinically presents in three forms,***,gastrointestinal and *** 95%of human anthrax is cutaneous and 5%is *** anthrax is very rare(less than 1%).Inhalational form is used as a biological warefare agent. Penicillin,ciprofloxacin(and other quinolones),doxicyclin,ampicillin,***, clarithromycin,vancomycin,chloramphenicol,rifampicin are effective antimicrobials. Antimicrobial therapy for 60 days is *** anthrax vaccine is available. Administration of anti-protective antigen(PA) antibody in combination with ciprofloxacin produced 90%-100%*** combination of CPG-adjuvanted anthrax vaccine adsorbed(AVA) plus dalbavancin significantly improved survival.

关键词： Anthrax Bacillus anthracis Zoonotic disease Contagious disease Cutaneous anthrax Inhalational anthrax Gastrointestinal anthrax Human anthrax

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一步浸渍合成具有多重孔隙的铸型炭体(英文)

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新型炭材料 2003年第4期18卷 265-270页

作者：陆安慧 Jan-Henrik smtt mika Lindn Ferdi Schüth max-Planck-Institut für Kohlenforschung Kaiser-Wilhelm-Platz 1D-45470 Mülheim an der Ruhr max-Planck-Institut für Kohlenforschung Kaiser-Wilhelm-Platz 1 D-45470 Mülheim an der Ruhr

　以多孔块状硅体为模板,通过一步浸渍、炭化、酸处理工艺,制备出结构可控、孔隙联通且具有多重孔隙的铸型炭体。分别采用氮吸附技术、高分辨透射电镜和扫描电镜对模板硅、硅碳复合物及相应炭体进行了结构表征。从微米尺度分析,该炭体... 详细信息

　以多孔块状硅体为模板,通过一步浸渍、炭化、酸处理工艺,制备出结构可控、孔隙联通且具有多重孔隙的铸型炭体。分别采用氮吸附技术、高分辨透射电镜和扫描电镜对模板硅、硅碳复合物及相应炭体进行了结构表征。从微米尺度分析,该炭体是由高度联接的枝状结构单元为骨架构筑而成。与模板硅相比较,此炭体是硅体的正复本。从纳米尺度分析,这种炭体枝状骨架是由分布均匀且相互连接的中孔构成,此中孔及其孔壁对应于模板硅的孔壁及中孔,是多孔硅的负复本。此外构成中孔的炭骨架本体又含有大量炭化过程产生的微孔。因此该法合成的铸型炭具有孔隙高度发达和结构层层嵌套的特点。

关键词：铸型炭体一步浸渍法合成多重孔隙结构表征

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Coexistence and fluctuations phenomena with Davidson-like potentials in quadrupoleoctupole deformed nuclei

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Communications in theoretical Physics 2021年第3期73卷 105-118页

作者： m m Hammad W H mansour E m El-maghraby H A motaweh Ayman A Aly Faculty of Science Mathematics DepartmentDamanhour UniversityEgypt Faculty of Science Physics DepartmentDamanhour UniversityEgypt

the energy spectra of three types of two-dimensional potentials(we will call them‘Davidson-like potentials’(DLPs)),characterized by four minima separated by barriers,are *** predictions for spectra and wave functions are obtained by using the nine-point finite-difference *** these potentials,with the existence of a single configuration,a transition of spectra,as a function of barrier height,is covered from tunneling splitting modes to fluctuations phenomena,with equal peaks wave functions,crossing to the spectra of purely anharmonic oscillator potentials(AOPs).A different type of phase transition occurs when two(or more)configurations *** the change of the parameters,a transition of spectra is covered from coexistence phenomena of two distinct quantum tunneling modes to fluctuations phenomena,with unequal peaks wave functions,crossing to the spectra of purely *** DLPs,a particular application of the coherent quadropole-octupole model to describe energy bands with alternating parity of the nuclei^(100)mo,^(146,148)Nd,^(148,150)sm,^(220)Ra,^(220,222)Rn,and^(220,222)th is *** global parametrization of the model for the selected nuclei is achieved.

关键词： quantum phase transitions fluctuations phenomena coherent quadrupole-octupole motion model coexistence phenomena

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Geotectonic significance of the Neoproterozoic ophiolitic metagabbros of muiswirab area,South Eastern Desert,Egypt:constraints from their mineralogical and geochemical characteristics

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Acta Geochimica 2020年第6期39卷 887-910页

作者： moustafa m.mogahed Wlaa mahmoud Saad Geology Department Faculty of ScienceBenha University-EgyptP.O.Box 13518BenhaEgypt

Petrological and geochemical studies of Neo-proterozoic metagabbros were carried out in the muiswirab area,South Eastern Desert of *** muiswirab area comprises of ophiolitic metagabbroic rocks(mOm),which are tectonically thrusted over a thick pile of metavolcanic rocks and intruded by syn-and post-tectonic granitoid *** whole-rock geochemical variations coupled with chemical compositions of mineral constituents are used to attain the genesis and tectonic evolution of the studied *** geothermobarometric investiga-tion of the analyzed amphiboles from(mOm)revealed that these metagabbros underwent regional metamorphism under lower to upper greenschist facies(biotite zone)conditions(at a temperature of 450 to 500℃and pressure of 1-3 kbar).Geochemically,the metagabbros(mOm)show tholeiitic affinity and cxhibiting both arc-and mORB-like characters as evidenced by their clinopyrox-ene compositions and the Ti/V ratios(11.84-31.65),which considered as prominent features of forearc tectonic *** geochemical features suggest a probable fractionation of olivine±clinopyroxene±plagioclase as well as insignificant crustal *** parental magma of the investigated mOm rocks seems to be developed in a sub-arc mantle wedge setting due to the enrichments of LILE(e.g..Rb,Ba,Sr,Pb)over HFSE(e.g,Ti,Nb,Y,Zr,Hf,Ta).the studied mOm rocks have lower values of Nb/U relative to mORB and OIB indicating that their geochemical variation produced due to the enrichment of a lithosphere mantle by OIB like *** ratios of Zn/Fet,La/sm,sm/Yb,th/Yb and Nb/Yb indicate that the mOm rocks represent a fragment of oceanic crust originated at a supra-subduction zone environment and their parental magma developed by 5-30%partial melting of a spinel lherzolite mantle rather than pyroxenite in an island arc setting and conformable with most of the Egyptian ophiolitic metagabbros.

关键词： Egypt Eastern Desert muiswirab area Ophiolitic metagabbros N-mORB Arc tholeiites Foreare tectonic regime Volcanic-arc setting

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Hylocomium splendens (Hedw.) *** Pleurozium schreberi (Brid.) *** trace element bioindicators:Statistical comparison of bioaccumulative properties

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Journal of Environmental Sciences 2013年第2期25卷 340-347页

作者： Sabina Doegowska Zdzisaw m.migaszewski Artur michalik Geochemistry and the Environment Division Institute of ChemistryJan Kochanowski University15GSwietokrzyska St25-406 KielcePoland

the principal objective of this study was to compare bioaccumulative properties of two terrestrial moss species Hylocomium splendens and Pleurozium schreberi from the Kielce area （south-central Poland）, using various statistical techniques. Forty-six moss samples from 23 sampling sites located within the city limits were analyzed for 33 trace elements. the results indicated that 17 elements （Ba, Ce, Co, Cu, Eu, Fe, Gd, Hg, La, mo, Nd, Ni, Pb, Pr, sm, V, Y） dominated in H. splendens, whereas only three elements （mn, Sr, Zn） occurred in excessive amounts in P. schreberi. No differences in the distribution pattern of Dy, Er, Ho, Sn, Tb, th and Yb were observed. the element concentration ratio （PI/Hy） varied from 0.50 to 1.19. For 14 elements （Ce, Co, Cu, Fe, Gd, Hg, La, mo, Nd, Ni, Pb, sm, th, V）, PI/Hy 〈 1; for 4 elements （Cd, mn, Sr, Zn）, PI/Hy 〉 1; for 7 elements （Ba, Dy, Er, Eu, Pr, Y, Yb）, PI/Hy = equalled 1. Czekanowski＇s method showed similarities in rare earth element concentrations for both moss species. the cluster analysis exhibited three significant clusters at D link /D max × 100 〈 50 for both moss species. Strong positive Spearman correlations between both moss species were recorded for the following pairs：Ba-Ba, Co-Co, Er-Er, Eu-Eu, Gd Gd, mn-mn, Ni-Ni, Pb-Pb, Pr-Pr, sm-sm, th-th, Y-Y, and Yb-Yb. Nonparametric tests （Sign test, Wilcoxon tests） showed statistically significant differences only for Cd, Ce, Co, Cu, Hg, mo, Ni, Pb and Sr. the scanning electron microscope study of H. splendens and P. schreberi revealed a different morphology of these species with no injuries.

关键词： biomonitoring trace elements moss species accumulative properties comparison

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Update on pythiosis immunobiology and immunotherapy

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World Journal of Immunology 2014年第2期4卷 88-97页

作者： érico S Loreto Juliana sm Tondolo Régis A Zanette Sydney H Alves Janio m Santurio Department of microbiology and Parasitology Universidade Federal de Santa Maria Programa de Pós-graduacao em Ciências Farmacêuticas Universidade Federal de Santa Maria

Pythiosis is an invasive, ulcerative, pyogranulomatous disease caused by Pythium insidiosum, a fungus-like oomycete that has been reported to affect humans, horses, dogs, and other mammals mainly in tropical and subtropical areas of the world. the disease is characterized by an eosinophilic granulomatous and a th2 immune response which in turn helps to protect the fungus from the host cells. Pythiosis can present clinically in subcutaneous, gastrointestinal, and vascular tissues or in a systemically disseminated form depending on the species and site of infection. Changes in iron metabolism and anemia are commonly observed. the diagnosis is accomplished through clinical and pathological features, laboratory characteristics of cultures, serological and molecular tests. Treatment includes radical surgery, antimicrobial drugs, immunotherapy or a combination of these treatments. Immunotherapy is a practical and non-invasive alternative for treating pythiosis which is believed to promote a switch from a th2 to th1 immune response, resulting in a favorableclinical response. this therapy has demonstrated cure rates above 70% and 55% in horses and humans but low cure rates in dogs and cats. Despite the curative properties of this type of immunotherapy, the antibodies that are produced do not prevent host reinfection. thus, development of effective adjuvants and new diagnostic techniques for early disease diagnosis are of utmost importance. the aim of this review was to promote pythiosis awareness and to provide an update about the immunotherapy and immunobiology of this disease.

关键词： Pythium insidiosum Treatment Pythiosis Immunotherapy Pathogenesis

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Late Neoarchean crustal growth under paired continental arc-back arc system in the North China Craton

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Geoscience Frontiers 2021年第3期12卷 437-457页

作者： Xin He Wei Wang m.Santosh Jiachen Yao Kangting Gao Yuhan Zhang Denggang Lu Lishuang Guo the State Key Laboratory of Geological Processes and mineral Resources School of Earth Sciences and ResourcesChina University of GeosciencesBeijing 100083PR China Department of Earth Sciences University of AdelaideSA 5005Australia National Institute of Natural Hazards MEMCBeijing 100085PR China

the late Archean(~3.0-2.5 Ga)was a key period of continental growth globally,which is widely considered to reflect the onset of vigorous plate tectonic activity,although related continental growth modes remain *** we investigate a suite of late Neoarchean metavolcanic rocks from the southwest Qixia area of the Jiaobei terrane in the North China *** rocks in this suite include amphibolites,clinopyroxene amphibolites,and hornblende plagioclase *** present zircon U-Pb isotopic data which indicate that the protoliths of these rocks formed during~2549-2511 ***(clinopyroxene)amphibolites correspond to meta-basaltic rocks,with some containing high modal content of *** rocks show moderate to high FeO_(T)(8.96-13.62 wt.%)and TiO_(2)(0.59-1.59 wt.%),flat to less fractionated REE patterns,and mildly negative th,Nb,and Ta anomalies,resembling those of *** addition,they display positive zirconε_(Hf)(t)values(+2.6 to+8.7),and are devoid of crustal contamination or fractional *** with the low Nb/Yb(mostlysm)_N(mostlymoderate th/Yb(0.08-0.54),and low V/Sc(5.53-9.19)ratios,these basaltic rocks are interpreted to have been derived from a relatively reduced and depleted mantle source that was mildly metasomatized by hydrous *** hornblende plagioclase gneisses are meta-andesitic rocks,and occur interlayered with the basaltic *** are transitional between tholeiitic and calc-alkaline rock series,and show fractionated REE patterns with evidently negative th,Nb,and Ta *** depleted zirconε_(Hf)(t)values(+2.4 to+8.4)and quantitative chemical modeling suggest that the andesitic rocks were most likely generated by injection and mixing of juvenile felsic magmas with the tholeiitic basaltic *** general,the chemical features and genesis of late Neoarchean meta-basaltic rocks in our study area resemble those of mariana back-arc basin *** with regional ge

关键词： Late Neoarchean metavolcanic rocks Continental growth Paired continental arc-back arc Jiaobei terrane North China Craton

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Neutron Activation Analyses Used to Study Elemental Accumulation in Some marine macrophytes (mediterranean Sea Coast of Egypt)

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American Journal of Analytical Chemistry 2017年第6期8卷 395-405页

作者： N. Nassar A. Kravtsova m. Frontasyeva m. m. Sherif Department of Physics Faculty of Science Cairo University Giza Egypt FLNP JINR Dubna Russia the A.O. Kovalevsky Institute of marine Biological Research of RAS Sevastopol Russia

the concentrations of Na, mg, Al, S, Cl, K, Ca, Sc, Ti, V, Cr, mn, Fe, Co, Ni, Zn, As, Se Br, Rb, Sr, Zr, mo, Ag, Sb, I, Cs, Ba, La, sm, Eu, Tb, Yb, Hf, Ta, W, Au, th and U in 6 types of marine macrophytes (algae and seagrass): Gelidium pusillum (Stackhouse) Le Jolis, Ulva intestinalis Linnaeus, Amphiroa rigida J.V. Lamouroux, Hypnea sp., Cystoseira sp. and Posidonia oceanica (L.) Delile (seagrass) collected from 3 stations along the mediterranean Sea coast of Egypt were determined using instrumental neutron activation analysis. the contents of elements in marine macrophytes indicated that they accumulated elements at different levels depending on their type of species (brown, red, green and seagrass) and the ambient water conditions. However, the concentrations of Cr, Co, Ni, Se, Zr, mo, Ag, Cs, La, sm, Eu, Yb, Hf, Ta, Au and U were very similar in all samples. In general the levels of classically investigated elements, particularly mn, Fe, Co, Ni and Zn determined in the macrophytes in the present study are lower or within the wide range of values previously reported for species of these genera sampled along the Egyptian mediterranean coast.

关键词： Algae and Seagrass Elemental Analysis mediterranean Sea Neutron Activation Analysis

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Synthesis,structure and magnetic properties of sm_(1.2)Ho_(0.8)Fe_(17)Hx(X=0;4.4)

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Journal of Rare Earths 2021年第9期39卷 1089-1094页

作者： S.V.Veselova m.A.Paukov I.S.Tereshina V.N.Verbetsky K.V.Zakharov D.I.Gorbunov A.N.VasiPev Faculty of Physics M.V.Lomonosov Moscow State UniversityMoscow 119991Russia Nuclear Fuel Cycle Department.Centrum Vyzkumu Rez Hlavni 130Husinec-Rez 25068.Czech Republic Immanuel Kant Baltic Federal University Kaliningrad 236004Russia Faculty of mathematics and Physics Charles UniversityPrague 12116Czech Republic Hochfeld-magnetlabor Dresden(HLD-EmFL) Helmholtz-Zentrum Dresden-RossendorfDresden 07328Germany f National Research South Ural State UniversityChelyabinsk 454080Russia

Intermetallic compounds based on rare-earth metals and iron are by far the most promising materials for permanent mag *** this work,the multicomponent compound sm_(1.2)Ho_(0.8)Fe_(17)was prepared by in duction *** hydride sm_(1.2)Ho_(0.8)Fe_(17)H_(4.4)with a high hydrogen content was obtained by direct hydrogenation of the intermetallic *** rhombohedral th2Zn17-type of structure(space group R3^(-)m)is inhere nt to parent compound and hydride as *** effect of hydrogenation on the magneric properties of sm_(1.2)Ho_(0.8)Fe_(17)was *** temperature of the hydride sm_(1.2)Ho_(0.8)-Fe_(17)H_(4.4)is higher than that of parent compound by△Tc=138 *** hydrogen embedded in sm_(1.2)Ho_(0.8)Fe_(17)crystal lattice in creases the saturation magnetization(σs)at T=300 K,but does not significantly affect%at T=4.2 *** ferrimagnetic structure is retained in magnetic fields up to 58 T in the parent compound,while,in the hydride,there is a spin-reorie ntatio n phase transitio n observed at 55 *** is found that the parameter of the in tersublattice exchange interaction decreases significantly in the hydride sm_(1.2)Ho_(0.8)Fe_(17)Hg_(4.4)(and in the nitride sm_(1.2)Ho_(0.8)Fe_(17)N_(2.4))which is associated with boosting of the unit-cell volume and distances between magnetic ions.

关键词： Intermetallic compound Hydride Crystal structure magnetization magnetic phase transition Exchange interaction

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