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核科学与工程 1991年第4期11卷 380-384页

作者：毛家骏 ch. Keiling G.Marx 同济大学分析测试中心柏林自由大学放化研究室

一、引言被长期贮存或处置的放射性物质能回到人类环境中来的最可能途径是通过地下水的流动,这种核素迁移的过程可能会因放射性核素和地质介质以及其他物质间相互作用而被阻滞.

关键词：铀铯硒岩盐吸附放射性

Ph.toph.sical Beh.viors of Azobenzene in Solvent-Swollen Nafion Membranes

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ch.nese ch.mical Letters 1996年第10期7卷 944-947页

作者： Guan, JQ Tung, ch ACAD SINICA INST PHOTOG CHEMBEIJING 100101PEOPLES R CHINA

Th. fluorescence from azobenzene (AB) molecule incorporated into water-swollen Nafion in acid form was observed at room temperature for th. first time. Th. incorporation process was investigated by UV absorption. Th. plot of th. concentration of AB in Nafion vs. th. soaking time sh.ws th.t th. adsorption process is diffusion-controlled, and th. apparent diffusion coefficient (D) was determined to be 7.6x10(-10) cm(2)s(-1). Th.se results are attributed to th. fact th.t AB molecules are located in th. fluorocarbon/water interface of th. Nafion membranes and are protonated. In meth.nol-swollen Nafion membranes, AB fails to fluoresce because it is located at th. meth.nol pool enclosed by th. cluster networks.

关键词： Ph.toph.sical Beh.viors of Azobenzene in Solvent-Swollen Nafion Membranes

Semiconductor ph.toinduced cycloreversion of th. dimer of meth.l 2-naph.h.ate

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ch.nese Journal of ch.mistry 1997年第3期15卷 260-264页

作者： Tung, ch.Ying, YM Institute of Ph.tograph.c ch.mistry Chinese Academy of Sciences Beijing 100101 China [*]Institute of Ph.tograph.c ch.mistry Chinese Academy of Sciences Beijing 100101 China

Th. dimer of meth.l 2-naph.h.ate (I) h.s been found to undergo efficient cycloreversion to its monomer, meth.l naph.h.lene-2-carboxylate (2) on illuminated ZnO and TiO2 but not on CdS. An electron transfer and cation radical ch.in mech.nism is proposed. Quantum yields, solvent effect. th. role of oxygen, and th. quench.ng of th. reaction were investigated, and were consistent with.th. proposed mech.nism.

关键词： semiconductor ph.toinduced cycloreversion electron transfer

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绵绵银幕情

Ph.tosensitized Cycloreversion of Cage Compound via Triplet Energy Transfer

作者： ch.·海曼(ch. h.gh.am)

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ch.nese ch.mical Letters 1996年第9期7卷 794-796页

作者： Tung, ch.Ying, YM ch.NESE ACAD SCI INST PHOTOG CHEMBEIJING 100101PEOPLES R CHINA

Several triplet sensitizers were found to be able to ph.tosensitize cycloreversion of th. ph.todimer (1) of meth.l naph.h.lene-2-carboxylate. With.th. increase of th. donor's triplet energy, th. quantum yield of th. i... 详细信息

关键词： Ph.tosensitized Cycloreversion of Cage Compound via Triplet Energy Transfer

Can a dam type of an alpine lake be derived from lake geometry?A negative result

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Journal of Mountain Science 2021年第3期18卷 614-621页

作者： Adam EMMER Vojtěch.CURIN University of Graz Institute of Geography and Regional ScienceCascade|The Mountain Processes and Mountain Hazards GroupGraz 8010Austria Czech.Academy of Sciences Prague 16500Czechia Global ch.nge Research.Institute Czech University of Life Sciences PragueFaculty of Environmental SciencesBrno 60300Czechia

Glacial lake outburst floods(GLOFs)represent one of th. most serious h.zard and risk in deglaciating h.gh.mountain regions worldwide and th. need for GLOF h.zard and risk assessment is *** a consequence,numerous region-and nation-wide GLOF assessment studies h.ve been publish.d *** studies cover large areas and consider h.ndreds to th.usands of lakes,prioritizing th. h.zard posed by ***,certain simplification is required for executing such.studies,often resulting in neglecting qualitative ch.racteristics wh.ch.would need manual *** lake dam types(e.g.,bedrock-dammed,moraine-dammed)are often not distinguish.d,despite th.y control GLOF mech.nism(dam overtopping/dam breach.and th.s GLOF *** th.s study,we explore th. potential of easily measurable quantitative ch.racteristics and four ratios to approximate th. lake dam *** dataset of 851 lakes of th. Cordillera Blanca suggests th.t wh.le variances and means of th.se ch.racteristics of individual lake types differ significantly(F-test,t-test),value distribution of different geometrical properties can’t be used for th. originally proposed purpose along th. *** only promising results are obtained for extreme values(selected bins)of th. *** instance,th. low width.to length.ratio indicates likely morainedammed lake wh.le th. h.gh.value of ratio indicating round-sh.pe of th. lake indicates increased likelih.od of bedrock-dammed ***,we report a negative result of our experiment since th.re are negligible differences of relative frequencies in most of th. bins along th. spectra.

关键词： Alpine lake h.gh.mountain lake GLOFs Glacial lake Moraine-dammed Bedrock-dammed Negative result Cordillera Blanca

Extracts of Melia azedarach.Increases Mulberry Wh.tefly Mortality with.ut Affecting Silkworm Survivorsh.p

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Advances in Entomology 2016年第5期4卷 293-298页

作者： Antonios E. Tsagkarakis Rodanth. Babili Pasch.lis h.rizanis Dionyssios ch. Perdikis Laboratory of Agricultural Zoology and Entomology Agricultural University of Athens Athens Greece Laboratory of Sericulture and Apiculture Agricultural University of Athens Athens Greece

Melia azedarach.L. extracts were studied in comparison with.selected synth.tic in-secticides against th. mulberry wh.teflies Pealiusma ch.li and P. mori under labora-tory conditions. Morus alba (cv. “Early Spring”) leaves infested by mulberry wh.te-flies were exposed to Melia extracts of green fruits, l-cyh.loth.in (10% a.i.) and con-trol. Also, wh.te mulberry leaves after treatment with.th. same insecticides were provided to silkworms for consumption. Results h.ve sh.wn th.t th.re were signif-icant differences in th. nymph.l mortality of th. wh.teflies among treatments. Melia extracts and l-cyh.loth.in were effective in increasing wh.tefly mortality 24 h.after application. Furth.rmore, Melia extracts didn’t affect silkworm survivorsh.p, wh.ch.was severely affected by l-cyh.loth.in treatment, since all th. silkworms fed on treated leaves were found dead. Th.s, th.se extracts migh. be considered a potential alternative in management of th. mulberry wh.teflies.

关键词： Mulberry Wh.teflies Control Melia azedarach Extract Silkworm

Geoch.mistry and mineral ch.mistry of th. armoor granitoids,eastern dh.rwar craton: implications for th. redox conditions and tectono-magmatic environment

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Acta Geoch.mica 2024年第1期43卷 110-133页

作者： A.Ajay Kumar ch.Ash.k Department of Geology Osmania UniversityHyderabad 500007India CSIR-National Geoph.sical Research.Institute UppalHyderabad 500007India

Th. mineralogical and geoch.mical ch.racteristics of th. K-rich.granites from th. Armoor granitic rocks in th. north.astern portion of th. Eastern Dh.rwar Craton(EDC) are *** order to understand its ph.sicoch.mical conditions,th. petrogenesis of th. granitoid was explained from biotite ch.mistry and geoch.mical *** of mineral ch.mistry expose th.t compositionally,K-feldspar and plagioclase in Armoor granite rocks range from An0,Ab_(3-5.9),Or_(94-96.9) and An_(5-29,-Ab71.9-94.9),Or_(0-1.5),*** mineral ch.mistry of biotite crystals exh.bits composition th.t varies from primary to re-equilibrated primary *** biotites from th. Armoor granites generally exh.bit an I-type trend,with.calc-alkaline parental magma in a subduction *** ch.mistry of granites displays magnetite(oxidized)series nature,wh.ch.h.s oxygen fugacity(fO_(2))=-15.1 to-16.7(log_(10) bar),under h.gh.oxidizing *** and pressure estimates for th. crystallization of Armoor granites based on biotite composition are T=612-716 ℃ and 1.0-0.4 kbar,***,th.se rocks are metaluminous to sligh.ly peraluminous and magnesian,with.calc-alkaline potassiumrich.*** th. ch.ndrite normalized REE diagram,th. granites h.ve positive europium anomalies;rich.Sr/Y,(Dy/Yb)_(N) ratios and reduced Mg#,Rb/Sr,Rb,Sr indicate th.t th. melting of earlier rocks,crystal accumulation and residual garnet source formed at h.gh.*** examined granites sh.w th.t th.y are produced from th. melting of crustal ***,th. extensive analyses of th. described Armoor granite suggest th.t th.y were produced by crust sources and developed under oxidizing conditions in subduction setting.

关键词： Armoor granites Oxygen fugacity Crystal accumulation Remelting Subduction

Multirange Fractal Analysis on th. Negative Correlation between Fractal Dimension of Fractured Surface and Tough.ess of Materials

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Journal of Materials Science & Tech.ology 1996年第4期12卷 318-320页

作者： Lung, CW Jiang, JA Zh.ng, ch International Centre for Materials Ph.sics Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

Applying th. concept of multirange fractals, a new explanation to th. Williford's multifractal curve on th. relationsh.p of fractal dimension with.fracture properties in materials h.s been given. It sh.ws th. importance of factorizing out th. effect of fractal structure from oth.r ph.sical causes and separating th. appropriate range of scale from multirange fractals.

关键词： Fracture

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车胎概述

名车志 2000年第2期 88-89页

作者： ch.,L.h.