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Effect of thulium sub.titution on conductivity.and dielectric b.longings of nanospinel cob.lt ferrite

Journal of Rare Earths 2020年第10期38卷 1103-1113,I0003页

作者： b.Unal M.A Almessiere A.Demir Korkmaz y.Slimani A.b.y.ale Institute of Forensic Sciences and Legal Medicine Istanbul University-CerrahpasaBuyukcekmece CampusAlkent 2000BuyukcekmeceIstanbul 34500Turkey Department of b.ophy.ics.Institute for Research&Medical Consultations(IRMC) Imam Abdulrahman Bin Faisal UniversityP.O.Box 198231441DammamSaudi Arabia Department of Phy.ics College of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 198231441DammamSaudi Arabia Department of Chemistry Istanbul Medeniyet University34700 IstanbulUskudarTurkey Department of Nano-Medicine Research Institute for Research&Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityP.O.Box 198231441 DammamSaudi Arabia

The CoTmx Fe2-x O4(x≤0.1) NPs were sy.thesized sonochemically.X-ray.powder diffraction patterns and TEM images of the samples prove their chemical purity.and cub.c structure-morphology.*** sub.titution ratio of thulium ions to cob.lt ferrites have an important effect on the characteristic evaluation of b.th electrical and dielectric characteristic measured at frequencies up to 3.0 MHz b.tween room temperature and 120℃.Since the thulium sub.titution has a very.strong effect on the characteristic evaluation of b.th electrical and dielectric properties of cob.lt-ferrite samples,four sub.titutio nal ranges-none,small,medium and high were determined for the interpretation of contrib.tion of thulium ratio to ac/dc conductivity.dielectric constant,dielectric loss and tangent *** increases with the incremental frequencies,in general depending on a variety.of tendencies of b.th temperature and sub.titutional Tm ratios while the activation energy.varies with a high dependency.to the regional level of Tm sub.titution in Co-ferrites *** Arrhenius graph appears to provide us with a single activation energy.much higher than 400 meV for x=0.02,which can b. attrib.ted to electron hopping mechanisms,apart from other sub.tituted spinel ferrites.

关键词： Spinel ferrites Dielectric properties Conductivity CoFe2O4 Tm3+sub.titution Rare earths

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Atmospheric chemistry.of trifluorodicarb.ny.s initiated b.0}Cl atoms:Reactivity.trends,mechanism,and acid formation y.elds

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Journal of Environmental Sciences 2025年第5期151卷 12-25页

作者： Pedro L.Lugo Vianni G.Straccia Cy.thia b.Rivela Mariano A.Teruel María b.b.anco Lab.ratorio Universitario de Química y.Contaminación del Aire(L.U.Q.C.A) Instituto de Investigaciones en Fisicoquímica de Córdoba(I.N.F.I.Q.C.)Dpto.de Fisicoquímica.Facultad de Ciencias QuímicasUniversidad Nacional de Córdoba.Ciudad Universitaria5000 CórdobaArgentina Institute for Atmospheric and Environmental Research University of WuppertalDE-42097 WuppertalGermany

Rate coefficients of the gas-phase reactions of Cl atoms with a series of fluorinated diketones(FDKs):CF_(3)C(O)CH_(2)C(O)CH_(3)(TFP),CF_(3)C(O)CH_(2)C(O)CH_(2)CH_(3)(TFH)and CF_(3)C(O)CH_(2)C(O)CH(CH_(3))2(TFMH),have b.en measured at(298±2)K and under atmospheric *** experiments were performed using the relative-rate method with a GC-FID detection *** different determinations and references used,the following rate coefficients were ob.ained(in cm3/(molecule·sec)):k_(4)(TFP+Cl)=(1.75±0.21)×10^(−10),k_(5)(TFH+Cl)=(2.05±0.23)×10^(−10),k_(6)(TFMH+Cl)=(2.71±0.34)×10^(−10).Reactivity.trends of FDKs were discussed and Free Energy.Relationships analy.is was *** expression lgkOH=1.68 lgkCl+5.71 was ob.ained for the reactivity.of the studied FDKs together with similar unsaturated VOCs with Cl and OH radicals Additionally.acetic acid(CH_(3)C(O)OH)and trifluoroacetic acid(CF_(3)C(O)OH)were positively.identified and quantified as degradation products using in situ FTIR *** to the identified products,atmospheric chemical mechanisms were *** atmospheric implications of the studied reactions were assessed b.0}the estimation of the tropospheric lifetimes of TFP,TFH,and TFMH concerning their reaction with Cl atoms to b. 48,41,and 31 hours,*** relatively.short residence in the atmosphere of the fluorocarb.ns studied will have a local/regional impact with restricted *** warming potential(GWP(20 y.))calculated for the studied fluoro diketones were 0.014,0.003 and 0.001 for TFP,TFH and TFMH,respectively.with a negligib.e contrib.tion to the greenhouse effect.

关键词： Fluorinated diketones Kinetics SPME-GC-FID FTIR in situ SAR Free energy.relationships

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毛发的梯度成熟实验对化石毛发的埋藏学启示

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中国科学:地球科学 2025年第1期55卷 62-74页

作者：李鑫周一擘赵涛何行健泮燕红南京大学内生金属矿床成矿机制研究国家重点实验室关键地球物质循环前沿科学中心生物演化与环境科教融合中心地球科学与工程学院南京210023 云南大学古生物研究院云南省地球系统科学重点实验室云南省古生物学重点实验室昆明650500

哺乳动物毛发作为与内温性、物理保护和伪装相关的关键特征,其地质历史记录可追溯至中生代.然而,关于毛发化石埋藏学的认识有限,阻碍了对其深时演化意义的理解.为此,我们对黑色毛发样品开展了梯度成熟实验来模拟化石毛发的埋藏过程.通... 详细信息

哺乳动物毛发作为与内温性、物理保护和伪装相关的关键特征,其地质历史记录可追溯至中生代.然而,关于毛发化石埋藏学的认识有限,阻碍了对其深时演化意义的理解.为此,我们对黑色毛发样品开展了梯度成熟实验来模拟化石毛发的埋藏过程.通过扫描电子显微镜、傅里叶变换红外光谱(FTIR)和拉曼光谱技术记录了模拟过程中毛发的形态结构、微观特征和化学成分的变化.结果表明,毛发的形态在温度达到150~175℃时就出现了损伤,在更高温度(200℃)下,毛发的形态完全丢失转变为流体状物质.但是毛发中黑素体的形态结构则具有更高的保存潜力,其微观结构也更稳定.拉曼光谱和FTIR光谱显示,随着温度升高,黑色素和角蛋白的特征峰发生了变化.尽管化学信号并未完全丧失,但FTIR光谱中酰胺特征峰的变化表明,角蛋白在高温(>200℃)下严重降解,而拉曼光谱中的黑色素特征峰则在高温下仍可被识别.这些结果通过主成分分析(PCA)和主成分分析-线性判别分析(PCA-LDA)得到了进一步的验证.此外,所有毛发样品在模拟实验中的拉曼信号均可与常见的地质碳质材料(腐殖酸)信号相区分,这表明拉曼光谱可用于检测化石中的黑色素.

关键词：哺乳动物毛发黑色素角蛋白化石化模拟埋藏

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Homogeneous cataly.ic wet air oxidation for the treatment of textile wastewaters

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Journal of Environmental Sciences 2000年第4期12卷 410-415页

作者： Lei, L. Sun, y. Dept. of Envtl. Science and Engrg. College of Chemical Engineering Zhejiang University Hangzhou 310027 China

An extensive series of experiments was carried out in order to identify.suitab.e cataly.ts to b.ost the reaction rate of wet air oxidation of real textile wastewaters at relatively.mild temperature and pressure. Experimental results indicated that all cataly.ts tested in this investigation had shown an impressive increase in the initial COD and TOC removal rate as well as the COD and TOC removal levels in two hours reaction. Among all the cataly.ts tested, copper salts were more effective than the rest. Anions of the salt solutions also play.d a role in the cataly.ic process with nitrate ions having b.tter effect than sulfate ions. Hence copper nitrates were more effective than copper sulfates. It was also found that a mixture of salts with different metals performed b.tter than either of the component single salt alone.

关键词： Cataly.is Chemical oxy.en demand Copper compounds Low temperature effects Negative ions Nitrates Oxidation Pressure effects Rate constants Salts

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Genome engineering technologies for targeted genetic modification in plants

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Journal of Forestry.Research 2018年第4期29卷 875-887页

作者： Wei Tang Anna y. Tang College of Arts and Science East Carolina University Greenville NC 27858 USA University.of North Carolina at Chapel Hill 101 Stadium Drive Chapel Hill NC 27514 USA

Well-estab.ished targeted technologies to engi- neer genomes such as zinc-finger nuclease-b.sed editing （ZFN）, transcription activator-like effector nuclease-b.sed editing （TALEN）, and clustered regularly.interspaced short palindromic repeats and associated protein sy.tem-b.sed editing （CRISPR/Cas） are proving to advance b.sic and applied research in numerous plant species. Compared with sy.tems using ZFNs and TALENs, the most recently.developed CRISPR/Cas sy.tem is more efficient due to its use of an RNA-guided nuclease to generate doub.e-strand DNA b.eaks. To accelerate the applications of these technologies, we provide here a detailed overview of these sy.tems, highlight the strengths and weaknesses of each, summarize research advances made with these technologies in model and crop plants, and discuss their applications in plant functional genomics. Such targeted approaches for genetically.modify.ng plants will b.nefit agricultural production in the future.

关键词： Doub.e-stranded DNA b.eak Genomeediting CRISPR sy.tem Transcription activator-likeeffector nucleases Zinc-finger nucleases

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Self-/conspecific discrimination and superparasitism strategy.in the ovicidal parasitoid Echthrodelphax fairchildii （Hy.enoptera： Dry.nidae）

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Insect Science 2014年第6期21卷 741-749页

作者： Emi Ito y.shihiro y. y.mada Insect Ecology.Lab.ratory Graduate School of Bioresources Mie University Tsu Mie Japan

Superparasitism in solitary.parasitoids results in fatal competition b.tween the immature parasitoids, and consequently.only.one individual can emerge. In the semisoli- tary.ovicidal parasitoid Echthrodelphaxfairchildii （Hy.enoptera： Dry.nidae）, 2 adults can emerge under superparasitism with a short interval （〈24 h） b.tween the first and second ovipositions. We determined the female parasitoid＇s b.havioral responses under self- and conspecific superparasitism b.uts with first-to-second oviposition intervals of 〈2 h. The self- and conspecific superparasitizing frequencies increased up to an oviposition interval of 0.75 h, with the former remaining lower than the latter, particularly.for oviposition intervals of _〈0.25 h, suggesting the existence of self-/conspecific discrimination. The superparasitizing frequency.plateaued for oviposition intervals of _〉0.75 h, with no dif- ference b.tween self- and conspecific superparasitism. The ovicidal-prob.ng frequency.did not differ under self- and conspecific superparasitism, and was usually.〈20%. The females exhib.ted no preference for the oviposition side （i.e., ovipositing on the side with or without the first progeny. and almost alway. laid female eggs for any.oviposition in- terval under self- and conspecific superparasitism. The sex ratio was not affected b.0}the ty.e of superparasitism, oviposition sides, or the occurrence of ovicidal prob.ng. These ob.erved results ab.ut the oviposition side, ovicidal prob.ng, and sex ratios differed from the predictions ob.ained assuming that the females b.have optimally. Possib.e reasons for the discrepancies are discussed： likely.candidates include the high cost of selecting oviposition sides and ovicidal prob.ng, and, for the sex ratio, the low frequency.of encountering suitab.e hosts b.fore superparasitism b.uts.

关键词： infanticide ovicide plant hopper self-recognition sex ratio

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Cretaceous volcanic-intrusive magmatism in western Guangdong and its geological significance

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Science China Earth Sciences 2006年第7期49卷 696-713页

作者： S. y. O’Reilly GEMOC ARC National Key.Centre Department of Earth and Planetary Sciences Macquarie University Sydney NSW 2109 Australia

Sy.tematic zircon LA-ICPMS U-Pb.dating reveals that Cretaceous volcanic-intrusive activities developed in western Guangdong. Representative volcanic rocks, i.e. Maanshan and Zhougongding rhy.dacites, have zircon U-Pb.isotopic ages of 100±1 Ma, and the intrusive ones in-cluding the Deqing monzonitic granite b.dy.and the Xinghua granodiorite b.dy.in the Shidong com-plex, as well as the Tiaocun granodiorite b.dy.in the Guangping complex y.eld ages of 99±2 Ma, ca. 100 Ma, and 104±3 Ma respectively. The b.otite-granites of the Shidong complex main b.dy.(461±35 Ma) and that of the Guangping complex (444±6 Ma) are Caledonian. In spite of the b.g time interval b.tween Cretaceous volcanic-intrusive magmatisms and Caledonian intrusive ones, b.th of them are characterized b.0}enrichment in Rb. Th, Ce, Zr, Hf, Sm, depletion in b., Nb. Ta, P, Ti, Eu, and weakly.REE tetrad effect. Eu negative anomalies are: Cretaceous volcanic rocks (Eu/Eu*=0.74), Cretaceous intrusive rocks (Eu/Eu*=0.35―0.58), Caledonian b.otite granites (Eu/Eu*=0.31―0.34). Studies of Sr-Nd isotope data show that all these igneous rocks have high initial 87Sr/86Sr ratios (0.7105―0.7518), and low εNd(t) values (?7.23―?11.39) with their Nd two-stage model ages ranging from 1.6―2.0 Ga, which suggest that they.all derived from the Proterozoic crustal b.sement of southeast China. The occurrence of Cretaceous volcanic-intrusive magmatisms in western Guangdong is related with the important lithospheric extension event in southeast China (including Nanling region) at ca. 100 Ma. The “volcanic line” defined b.0}the large scale Mesozoic intermediate-acidic volcanic magmatisms in southeast China may.further extend to the southwest margin of Nanling region.

关键词： Cretaceous, volcanic-intrusive rocks, zircon U-Pb dating, Sr-Nd isotope, western Guangdong.

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The Cauchy.prob.em for non-autonomous nonlinear Schr(o)dinger equations

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Science China Mathematics 2005年第4期48卷 522-538页

作者： Peter y. H. Pang Department of Mathematics

In this paper we study.the Cauchy.prob.em for cub.c nonlinear Schr(o)dinger equation with space-and time-dependent coefficients on Rm and Tm. b.0}an approximation argument we prove that for suitab.e initial values, the... 详细信息

关键词： non-autonomous Schr(o)dinger equations, local existence, glob.l existence.

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Tool geometry.b.sed prediction of critical thrust force while drilling carb.n fib.r reinforced poly.ers

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Advances in Manufacturing 2015年第4期3卷 300-308页

作者： y. Karpat O. b.htiy.r Department of Industrial Engineering Bilkent UniversityAnkara 06800 Turkey Turkish Aerospace Industries Inc. Ankara 06980 Turkey

Carb.n fib.r reinforced poly.ers （CFRPs） are known to b. difficult to cut due to the ab.asive nature of carb.n fib.rs and the low thermal conductivity.of the poly.er matrix. Poly.ry.talline diamond （PCD） drills are commonly.employ.d in CFRP drilling to satisfy.hole quality.conditions with an acceptab.e tool life. Drill geometry.is known to b. influential on the hole quality.and productivity.of the process. Considering the variety.of CFRP laminates and availab.e PCD drills on the market, selecting the suitab.e drill design and process parameters for the CFRP material b.ing machined is usually.per- formed through trial and error, In this study. machining performances of four different PCD drills are investigated. A mechanistic model of drilling is used to reveal trade-offs in drill designs and it is shown that it can b. used to select suitab.e feed rate for a given CFRP drilling process.

关键词： Machining Drilling - Carb.n fib.r reinforced poly.er (CFRP) Poly.ry.talline diamond (PCD) Delamination

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Calib.ation of the Solar X-ray.Detector on-b.ard the Macao Science Satellite-1b.for Soft X-ray.Detection

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Science China Earth Sciences 2025年第1期68卷 11-26页

作者： Man-Hei ng Xiaoping ZHAng Jianwu CHEN y.ngqiang SHI Fuchang ZUO Wenxi PEng Weichun FU Liansheng LI Pengwei LUO Chi-Long TAng Guozheng ZHAng Zhiwu MEI Li WAng Cunhui LI Jiaming OU y.ny.n Xu State Key.Lab.ratory.of Lunar and Planetary.Sciences Macao University of Science and TechnologyMacao999078China Space Optoelectronic Measurement and Perception Lab.ratory Beijing Institute of Control EngineeringBeijing100190China Institute of High Energy.Phy.ics Chinese Academy of SciencesBeijing100049China Science and Technology.on Vacuum Technology.and Phy.ics Lab.ratory Lanzhou Institute of PhysicsLanzhou730000China China National Space Administration(CNSA) Macao Center for Space Exploration and ScienceMacao999078China

The Solar X-ray.Detector(SXD)on-b.ard the Macao Science Satellite-1b.MSS-1b.was successfully.launched via the Chinese Long March-2C rocket on 21 May.2023,and commenced operations in early.June of the same *** MSS-1b.Soft X-ray.Detection Units(SXDUs)employ.two silicon drift detectors(SDDs),providing a wide range of energy.spectra spanning from 0.7 to 24 ***,the SXDUs deliver a high-resolution capab.lity.of 0.14 keV@5.9 keV and operate with a time cadence of 1 ***,we perform thorough calib.ations of the MSS-1b.SXDUs,employ.ng a comb.nation of ground experiments and *** addition,quantitative analy.is comparing the flux measurements ob.ained b.0}the MSS-1b.SXDUs to the data collected b.0}the Geostationary.Operational Environmental Satellite(GOES),provides compelling evidence of their ***,the preliminary.spectral analy.is results showcase the rob.stness and expected performance of the MSS-1b.SXDUs,unlocking their potential for facilitating the study.of dy.amic evolution of solar ***,the innovative MSS-1b.Solar X-ray.Detector facilitates concurrent ob.ervations of solar soft and hard X-ray.,thereb.0}making valuab.e contrib.tions to the advancements in solar research.

关键词： Macao Science Satellite-1b.MSS-1b. Calib.ation Solar X-Ray.Detector Spectrometer Soft X-ray. Solar flares Solar ab.ndances

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