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Geochemica. discrimina.ions of sa.dstones from the Mohe Forela.d ba.in,northea.tern China.Tectonic setting a.d provena.ce

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Science China.Ea.th Sciences 2005年第5期48卷 613-621页

作者： a.drey a. Sorokin Fa. Ea.t Bra.ch of Russia. a.a.emy of Sciences Blagoveshchensk 675000 Russia

Discrimina.ion of sa.dstone geochemistry to tectonic settings a.d provena.ce ha. become a. effective method in the studies of complex geologica. circumsta.ces beca.se of its higher sensitivity for the sta.ility of tectonic settings in the period of ba.in deposition. Results of geochemica. a.a.yses in this pa.er show tha. sa.dstone sa.ples of the Mesozoic Mohe ba.in fa.l in a.tive continenta. ma.gin settings on severa. kinds of tectonic discrimina.ory dia.ra.s (Bha.ia.et a.. 1983, 1986; Roser et a.. 1986,1988,1999). The sa.ples a.e a.so cha.a.terized by bina.y-system provena.ces, whose terrigenous cla.tic ma.eria.s ma.nly derived from the oro- genic belt nea. the ba.in to the north a.d seconda.ily from the continenta. region in the south of the ba.in a. the sa.e time. The resea.ch results of rock geochemistry, combined with tectonic a.a.ysis, reflect tha. tectonic type of the ba.in is a.forela.d ba.in with na.ure of depositiona. a.- cumula.ion of mola.s, but not continenta. rift ba.in considered in the pa.t. This finding provides importa.t evidence of rock geochemistry for the origina. structura. linka.e between the Mohe Forela.d Ba.in a.d Mongol-Okhotsk Orogen in Mesozoic.

关键词： Mohe Forela.d Ba.in, sa.dstone geochemistry, tectonic setting, provena.ce, Jura.sic.

Recent progress on ULF wa.e a.d its intera.tions with energetic pa.ticles in the inner ma.netosphere

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Science China.Technologica. Sciences) 2008年第10期51卷 1620-1625页

作者： Theodore a. FRITZ Center for Spa.e Physics Boston University Boston MA 02215 USA

The globa. distribution properties of Ultra.Low Frequency wa.e (ULF) in the inner ma.netospgere a.d its intera.tions with energetic pa.ticles, such a. the wa.e-pa.ticle resona.ce, modula.ion, a.d pa.ticle a.celera.ion, a.e a.tive topics in spa.e physics resea.ch. These problems a.e funda.enta.ly importa.t issues to understa.d the energy tra.sport from the sola. wind into the ma.netosphere. In this pa.er we briefly reviewed the recent resea.ch progress on ULF wa.e a.d its intera.tions with energetic pa.ticles in the inner ma.netosphere; furthermore, we suggested some open questions for future study.

关键词： ra.ia.ion belt pa.ticle pa.ticle a.celera.ion ULF wa.e compressiona. mode ca.ity mode poloida. mode toroida. mode Field Line Resona.ce (FLR) energetic pa.ticles modula.ion

Ea.ly Pa.eogene a.ctic terrestria. ecosystems a.fected by the cha.ge of pola. hydrology under globa. wa.ming:Implica.ions for modern clima.e cha.ge a. high la.itudes

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Science China.Ea.th Sciences 2010年第7期53卷 933-944页

作者： Ga.tha.a. La.GLOIS Depa.tment of Science a.d Technology College of Arts and Sciences Bryant University

Our understa.ding of both the role a.d impa.t of a.ctic environmenta. cha.ges under the current globa. wa.ming clima.e is ra.her limited despite efforts of improved monitoring a.d wider a.sessment through remote sensing technology. Cha.ges of a.ctic ecosystems under ea.ly Pa.eogene wa.ming clima.e provide a. a.a.ogue to eva.ua.e long-term responses of a.ctic environmenta. a.tera.ion to globa. wa.ming. This study reviews a.ctic terrestria. ecosystems a.d their tra.sforma.ion under ma.ked cha.ge of hydrologica. conditions during the wa.mest period in ea.ly Cenozoic, the Pa.eocene a.d Eocene. We describe a.new a.proa.h to qua.tita.ively reconstruct high la.itudina. pa.eohydrology using compound-specific hydrogen isotope a.a.ysis which a.plies empirica.ly derived genus-specific hydrogen isotope fra.tiona.ions to in situ biomolecules from fossil pla.ts. We propose a.moisture recycling model a. the a.ctic to expla.n the reconstructed hydrogen isotope signa.s of a.cient high la.itude precipita.ion during ea.ly Pa.eogene, which bea.s implica.ions to the likely cha.ge of modern a.ctic ecosystems under the projected a.celera.ed globa. wa.ming.

关键词： Pa.eogene clima.e a.ctic ecosystems globa. wa.ming globa. hydrology vegeta.ion cha.ge

Rota.ing pola.izer, compensa.or, a.d a.a.yzer ellipsometry

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Chinese Physics B 2013年第12期22卷 182-193页

作者： Sofya. a. Ta.a.Ta.er M. El-a.ez a.a. a. a.ka.oo Physics Depa.tment Islamic University of Gaza

In this pa.er we propose theoretica.ly a.set of ellipsometric configura.ions using a.rota.ing pola.izer, compensa.or, a.d a.a.yzer a. a.speed ra.io of N1ω：N2ω：N3ω. Different ellipsometric configura.ions ca. be obta.ned by giving different integra. va.ues to N1, N2, a.d N3. a.l configura.ions a.e a.plied to bulk c-Si a.d Ga.s to ca.cula.e the rea. a.d ima.ina.y pa.ts of the refra.tive index of the sa.ples. The a.cura.ies of a.l ellipsometric configura.ions a.e investiga.ed in the presence of a.hypothetica. noise a.d with sma.l misa.ignments of the optica. elements. Moreover, the uncerta.nties in the ellipsometric pa.a.eters a. functions of the uncerta.nties of the Fourier coefficients a.e studied. The compa.ison a.ong different configura.ions revea.s tha. the rota.ing compensa.or–a.a.yzer configura.ion corresponds to the minimum error in the ca.cula.ed optica. pa.a.eters.

关键词： ellipsometry pola.izer a.a.yzer compensa.or

Role of socia. a.d individua. experience in intera.tion of the mea.ow a.t Formica.pra.ensis （Hymenoptera. Formicida.） with la.ybird ima.ines a.d hoverfly la.va.

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Insect Science 2015年第3期22卷 440-450页

作者： Ta.ia.a.a. Novgorodova Institute of Systema.ics a.d Ecology of a.ima.s Siberian Branch of the Russian Academy of Sciences Frunze str. 11 Novosibirsk 630091 Russia

The a.ility to recognize a.hidopha.es is one of the key points in the protection a.ts provide a.hids a.a.nst their na.ura. enemies. Beha.ior of honeydew collectors from na.ure （＂field,＂ control） a.d la.ora.ory rea.ed ＂na.ve＂ a.ts of Formica.pra.ensis Retzius, which ha. never met either ＂ma.ure＂ workers or a.hids a.d a.hidopha.es, wa. observed during their pa.rwise intera.tions with la.ybird ima.ines a.d hoverfly la.va.. The ma.ority of the ＂na.ve＂ a.ts perceived la.ybirds a. a. enemy a. their first encounter a.ta.king them immedia.ely without a.y prior a.tenna.ion. a.ts seem to ha.e a.certa.n inna.e ＂enemy ima.e＂ tha. lets them rea.t very quickly to protect a.hids. Hoverfly la.va. were ra.ely a.ta.ked by both ＂field＂ a.d ＂na.ve＂ a.ts （〉 15%）. During tests with la.ybirds a.ts from na.ure a.ta.ked them a.d a.so demonstra.ed the most a.gressive rea.tions （series of bites a.d ＂dea.h grip＂） less frequently tha. the ＂na.ve＂ a.ts. The percenta.e of a.ts a.oiding a.hidopha.es a.ter a.conta.t with their chemica. defense （reflex bleeding a.d glue-like sa.iva. wa. significa.tly higher in the control group. Wherea. the ＂na.ve＂ a.ts did not lea.n to a.oid da.ger, fora.ers from na.ure usua.ly tried to a.oid nega.ive experience a.d used ta.tics of ＂short bites.＂ Overa.l, experience ha. been proved to be unimporta.t for displa.ing key beha.iora. rea.tions underlying a.t-la.ybird intera.tion. However, a.cumula.ion of experience ha. been a.sumed to pla. a. importa.t role in the forma.ion of beha.iora. stra.egy tha. a.lows honeydew collectors to drive a.hidopha.es a.a. with lower energy costs a.d a.oid or minimize nega.ive consequences of a.hidopha.es＇ chemica. defense.

关键词： a.ts a.hidopha.es defense enemy recognition Ha.monia.a.yridis Meligra.ma.tria.gulifera

Structure a.d dendroecology of Thuja.occidenta.is in disjunct sta.ds south of its contiguous ra.ge in the centra. a.pa.a.hia. Mounta.ns, USA

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Forest Ecosystems 2017年第1期4卷 55-65页

作者： Joshua.a. Kinca.d Shena.doa. University 1460 University Drive Winchester VA 22601 USA

Ba.kground： Informa.ion on forest structure, growth, a.d disturba.ce history is essentia. for effective forest ma.a.ement in a.dyna.ic la.dsca.e. Beca.se most of our resea.ch concerning the ecology a.d growth of Thujo ocddenra.is comes from sites in northern portions of its ra.ge, highly contextua. biotic a.d a.iotic fa.tors tha. a.fect the species in more southern loca.es ma. not be fully a.counted for. This resea.ch cha.a.terized the structura. a.tributes a.d growth dyna.ics of Thuja.occidentolis in disjunct forest sta.ds south of its contiguous ra.ge ma.gin. Methods： The Thujo occidenta.is forests exa.ined in this resea.ch were loca.ed in the centra. a.pa.a.hia. Mounta.ns, USa. a.proxima.ely 440 km south of the contiguous ra.ge ma.gin of the species. Forest structura. a.tributes were cha.a.terized in two Thujo occidenta.is forest sta.ds, which a.e ra.e in the region. Tree-ring chronologies were used to exa.ine the influences of disturba.ce a.d clima.e on the growth of Thuja.occidentolis. Results： The forests conta.ned a.tota. of 13 tree species with Thuja.occidenta.is contributing substa.tia.ly to the ba.a. a.ea.of the sites. Thujo occidenta.is stems were a.sent in the sma.lest size cla.s, while ha.dwood species were a.unda.t in the sma.lest cla.ses. Thuja.occidenta.is stems a.so were a.sent from the 〈 70 yea.s a.e cla.s. By contra.t, Thuja.occidenta.is sna.s were a.unda.t within sta.ds. Growth-relea.e events were distributed a.ross the disturba.ce chronology a.d genera.ly a.fected a.sma.l number of trees. The Thujo occidentolis tree-ring chronology possessed a. interseries correla.ion of 0.62 a.d mea. sensitivity of 0.25. The correla.ion between mea. tempera.ure a.d Thuja.occidenta.is growth wa. wea. a.d va.ia.le. Growth a.d moisture va.ia.les were more strongly correla.ed, a.d this rela.ionship wa. predomina.tly positive. Conclusions： Structura. a.tributes indica.e the forests a.e in the understory reinitia.ion sta.e of forest development. Silvicultura. ma.ipul

关键词： Northern white ceda. Disturba.ce Clima.e Ra.ge Disjunct Ra.ia. growth Regenera.ion

UNIFORM DECa. IN WEa.LY DISSIPa.IVE TIMOSHENKO SYSTEM WITH INTERNa. DISTRIBUTED DELa. FEEDBa.KS

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a.ta.Ma.hema.ica.Scientia 2016年第3期36卷 815-830页

作者： Tija.i a. a.a.a.A Depa.tment of Ma.hema.ics University of Hafr AI-Batin (UoHB) Hafr AI-Batin 31991 Saudi Arabia

In this pa.er we consider one-dimensiona. Timoshenko system with linea. fric- tiona. da.ping a.d a.distributed dela. a.ting on the displa.ement equa.ion. Under suita.le a.sumptions on the weight of the dela. a.d the wa.e speeds, we esta.lish the well-posedness of the system a.d show tha. the dissipa.ion through the frictiona. da.ping is strong enough to uniformly sta.ilize the system even in the presence of dela..

关键词： Timoshenko system well-posedness uniform sta.ility distributed dela.

Pa.a.oenvironmenta. Reconstruction of the Ea.ly to Middle Miocene Sequence in West Centra. Sina., Egypt, a. Revea.ed from Fossil Dia.oms

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a.ta.Geologica.Sinica.English Edition) 2018年第1期92卷 354-366页

作者： a.delfa.ta. a. Za.a. Depa.tment of Geology Faculty of Science Tanta University Tanta 31527 Egypt

a.deta.led a.a.ysis of the dia.oms from the sedimenta.y sequence exposed in a.u Qa.a.ba.in, west centra. Sina., wa. used to determine the pa.a.oenvironmenta. cha.ges during the Lower to Middle Miocene. a.tota. of 85 dia.om species a.d va.ieties belonging to 37 genera.were identified from 154 sa.ples collected throughout the stra.igra.hic succession. The lithologica. cha.a.ters of the studied sa.ples va.ied between sa.dstone, silty interbeds, sa.dy sha.es, sha.es, a.d termina.ed with a.hydrite a.d limestones. These rock units a.e included in two lithostra.igra.hic forma.ions （Rudies a.d Ka.eem）, which a.e sepa.a.ed by a.ma.ked unconformity. The distribution a.d preserva.ion of fossil dia.oms in the sedimenta.y record a.e exa.ined with the a.m of outlining the tempora. a.d spa.ia. va.ia.ion in the composition of the dia.om a.sembla.es, in order to estima.e the cha.ges in depositiona. environments during the Lower to Middle Miocene. The distributiona. pa.tern of the recorded dia.om ta.a.distinguished four dia.om eco-zones. The environment of ea.h eco-zone is deduced a.d a.proposed pa.eoba.hymetric cha.ge a.d depositiona. history of the Miocene sediments in the studied a.ea.a.e given.

关键词： pa.a.oenvironment Miocene sequence dia.oms west centra. Sina. Egypt

Unusua. rea.tion of a.tungsten a.kylidyne complex with ***,cha.a.teriza.ion,a.d crysta. structures of oxo trimers

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Science China.Chemistry 2011年第12期54卷 1903-1908页

作者： DOUGa. Brenda.a. Depa.tment of Chemistry University of Tennessee

The rea.tion of the a.kyl a.kylidyne W（CH2CMe3）3（=CSiMe3）（1） with H20 in THF a.d with D20 in benzene-d6 ga.e two new trimeric oxo complexes： W3O3（μ=O）3（CH2CMe3）6（THF）3 （2） a.d [W303（μ=O）3（Ch2CMe3）6（D2O）3] 2benzene-d6 （3.2benzened6）, respectively, ea.h conta.ning two a.kyl liga.ds per W a.om. This is in contra.t to the dimer W2o（β-O）（CH2CMe3）6, conta.ning three a.kyl liga.ds per W a.om, from the previously reported rea.tion of the a.kyl a.kylidyne a.a.og W（CH2CMe3）3- （=-CCMe3） with H2O. In the rea.tion of 1 with D20 in THF, a. unsta.le intermedia.e W2O2（μ-O）（CD2SiMe3）2（CH2CMe3）4 （4-d4） wa. identified. Kinetic studies of the rea.tions of 1 with excess H2O a.d D2O in THF-ds, yielding 4 a.d 4-d4, respectively, give a.kinetic isotope effect （KIE） of 3.46（3） a. 298（1） K, suggesting tha. the disa.pea.a.ce of 1 is a.ra.e-determining step.

关键词： a.kylidyne wa.er oxo complexes kinetic isotope effect