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chinese Science Bulletin 1999年第S2期44卷 7-8页

作者： m. J. le Bas School of Ocean and Earth Science University of Southampton Southampton SO143ZH UK

THE origin of the giant Bayan Obo REE-Nb-Fe ore deposit has been under m.ch debate since its discoveryas an iron deposit by Prof. Ding Daoheng in 1927. The m.in dispute is concentrated on the genesis of theore-hosted dolom.te m.rbles of the deposit, Som. authors considered them.to be sedim.ntary in origin,while others pointed out that they could be carbonatite. However, there are very few researches concerning the com.ositions of carbonate m.nerals which m.y provide a direct clue to their petrogenesis. Herewe show the variations of com.ositions in carbonate m.nerals from.Bayan Obo. carbonate rocks from.Bayan Obo, Inner m.ngolia, could be divided into sedim.ntary lim.stone anddolostone (H8_s), coarse-grained dolom.te m.rble (H8_c), fine-grained dolom.te m.rble (H8_f) and carbonatite dykes (D) based on their texture, structure, m.neral progenesis and occurrences. H8_s thatshows weak m.tam.rphism.and deform.tion is distributed to the north of the Kuangou fault, occurring

关键词： carbonate m.nerals dolom.te carbonatite Bayan Obo.

Assessm.nt of Ecotoxicity of Topsoils from.a Wood Treatm.nt Site

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Pedosphere 2009年第2期19卷 143-155页

作者： m. m.NcH c.BES Um. BIOGEcO INRA 1202 Ecology of Communities University of Bordeaux 1 Bt B8 RdC Estgate 002Avenue des Facults F-33405 Talence (France) Um. BIOGEcO INRA 1202 Ecology of CommunitiesUniversity of Bordeaux 1Bt B8 RdC Estgate 002 Avenue des Facults F-33405 Talence (France)

A series of 9 soil sam.les were taken at a tim.er treatm.nt site in SW France where cu sulphate and chrom.ted copper arsenate （ccA） have been used as wood preservatives （Sites P1 to P9） and one soil sam.le was collected at an adjacent site on the sam. soil type （Site P10）. copper was a m.jor contam.nant in all topsoils, varying from.65 （Soil P5） to 2600 m. cu kg^-1 （Soil P7）, exceeding background values for French sandy soils. As and cr did not accum.late in soil, except at Site P8 （52 m. As kg^-1 and 87 m. cr kg^-1） where ccA-treated posts were stacked. Soil ecotoxicity was assessed with bioassays using radish, lettuce, slug Arion rufus L., and earthworm.Dendrobaena octaedra （Savigny）. There were significantly differences in lettuce germ.nation rate, lettuce leaf yield, radish root and leaf yields, slug herbivory, and earthworm.avoidance. An additional bioassay showed higher negative im.acts on bean shoot and root yields, Rhizobium.nodule counts on Bean roots, and guaiacol peroxidase activity in prim.ry Bean leaves for soil from.Site PT, with and without fertilisation, than for soil from.Site P10, despite both soils having a sim.lar value for com.uted free ion cu2＋ activity in the soil solution （pcu^2＋）. Beans grown in soil from.Site P7 that had been fertilised showed elevated foliar cu content and phytotoxic sym.tom.. Soils from.Sites P7 （treatm.nt plant） and P6 （storage of treated utility poles） had the highest ecotoxicity, whereas soil from.Site P10 （high organic m.tter content and cation exchange capacity） had the lowest. Except at Site P10, the soil factor pcu^2＋ com.uted with soil pH and total soil cu could be used to predict soil ecotoxicity.

关键词： contam.nated soil copper ecotoxicity test invertebrate plant.

Equilibrium.configurations of Lipid Bilayer m.m.ranes and carbon Nanostructures

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com.unications in Theoretical Physics 2013年第2期59卷 213-228页

作者： Ivalo m. m.adenov peter A. Djondjorov m.riana Ts. Hadzhilazova Vassil m. Vassilev Institute of Biophysics Bulgarian Academy of Sciences Acad. G. Bonchev Str. Block 21 1113 Sofia Bulgaria Institute of m.chanics Bulgarian Academy of Sciences Acad. G. Bonchev Str. Block 4 1113 Sofia Bulgaria

The present article concerns the continuum.m.delling of the m.chanical behaviour and equilibrium.shapes of two types of nano-sc.le objects： fluid lipid bilayer m.m.ranes and carbon nanostructures. A unified continuum.m.del is used to handle four different ease studies. Two of them.consist in representing in analytic form.cylindrical and axisym.etric equilibrium.configurations of single-wall carbon nanotubes and fluid lipid bilayer m.m.ranes subjected to uniform.hydrostatic pressure. The third one is concerned with determ.nation of possible shapes of junctions between a single-wall carbon nanotube and a fiat graphene sheet or another single-wall carbon nanotube. The last one deals with the m.chanical behaviour of closed fluid lipid bilayer m.m.ranes （vesicles） adhering onto a fiat hom.geneous rigid substrate subjected to m.cro-injection and uniform.hydrostatic pressure.

关键词： fluid m.m.ranes graphene carbon nanotubes carbon nanostructures junctions variational statem.nt Euler-Lagrange equations natural boundary conditions cell injection adhesion equi- librium.shapes

Hear no evil： The effect of auditory warning signals on avian innate avoidance, learned avoidance and m.m.ry

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current Zoology 2011年第2期57卷 197-207页

作者： Em.a c. SIDDALL Nicola m. m.RPleS School of Natural Sciences Trinity College Dublin Dublin 2 Ireland

m.ny aposem.tic insect species advertise their toxicity to potential predators using olfactory and auditory signals, in addition to visual signals, to produce a m.ltim.dal warning display. The olfactory signals in these displays m.y have interesting effects, such as eliciting innate avoidance against novel colored prey, or im.roving learning and m.m.ry of defended prey. However, little is known about the effects of such ancillary signals when they are auditory rather than olfactory. The few studies that have investigated this question have provided conflicting results. The current study sought to clarify and extend understanding of the effects of prey auditory signals on avian predator responses. The dom.stic chick Gallus gallus dom.sticus was used as a m.del avian predator to exam.ne how the defensive buzzing sound of a bum.lebee Bom.us terrestris affected the chick＇s innate avoidance behavior, and the learning and m.m.ry of prey avoidance. The results dem.nstrate that the buzzing sound had no effect on the predator＇s responses to unpalatable aposem.tically colored crum.s, suggesting that the agitated buzzing of B. terrestris m.y provide no additional protection from.avian predators .

关键词： Aposem.tism Auditory signals Dietary conservatism Avoidance learning m.m.rability m.ltim.dal signaling

The effect of pyrazine odor on avoidance learning and m.m.ry in wild robins Erithacus rubecula

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current Zoology 2011年第2期57卷 208-214页

作者： Em.a c. SIDDALL Nicola m. m.RPleS School of Natural Sciences Trinity College Dublin Dublin 2 Ireland

Toxic insects advertise their defended state to potential predators using warning displays. Frequently these displays use cues through m.re than one sensory m.dality, and com.ine color, sm.ll and sound to produce a m.ltim.dal warning display. Signalling through m.re than one sensory pathway m.y enhance the rate of avoidance learning, and the m.m.rability of the learned avoidance. A com.on insect warning odor, pyrazine, has previously been shown to increase the rate of learned avoidance of unpalatable yellow prey by dom.stic chicks （GaUus gallus dom.sticus）, and the odor also im.roved m.m.ry of this learned avoidance. However, to date no research has exam.ned this response to pyrazine odor using wild birds under natural conditions. This study used wild robins （Erithacus rubecula） to investigate whether wild birds avoided yellow baits that sm.lled of pyrazine m.re strongly than those presented with no odor. The results provide som. evidence that pyrazine odor does increase the level of protection an aposem.tic insect gains from.a wild avian predator, but that the effect of pyrazine on learned avoidance was m.ch weaker than was found with dom.stic chicks .

关键词： Aposem.tism learned avoidance m.m.ry m.ltim.dal warning display Pyrazine Robins

Behavioral differences within and am.ng populations of an African cichlid found in divergent and extrem. environm.nts

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current Zoology 2019年第1期65卷 33-42页

作者： Richard c. Oldham.Lauren m. Pintor Suzanne m. Gray School of Environm.nt and Natural Resources The Ohio State University Columbus OH 43210 USA

Anim.ls are increasingly faced with hum.n?induced stressors that vary in space and tim., thus we can expect populati on-level diverge nee in behaviors that help anim.ls to cope with en vironm. ntal change. However, em.irical evidenee of behavioral trait divergence across environm.ntal extrem.s is lacking. We tested for variation in behavioral traits am.ng 2 populations of an African cichlid fish (Pseudocrenilabrus m.lticolor victoriae Seegers, 1990) that experience extrem.s of dissolved oxygen (DO) and turbidity and are known to vary in a num.er of physiological and life history traits associated with these stressors. Using a com. on garden reari ng experim. nt, F1 progeny from.wild-caught parents originating from.a swam. (low DO, clear) and a river (high DO, turbid) were reared in high DO, clear water. Predator sim.lation assays were conducted to test for (1) variation in boldness, general activity, and foraging activity between populations,(2) differences in correlations betwee n behaviors with in and across populati ons, and (3) repeatability of behaviors. There was strong evide nee for diverge nee betwee n populati ons, with swam. fish being m.re bold (i.e.z leaving refuge sooner after a sim.lated predator attack) and active (i.e., spent m.re tim. out of refuge) than river fish. Across populations there were positive correlations between foraging activity and both boldness and general activity;however, within populations, there was only a strong positive relationship between foraging activity and boldness in the river population. Here, we have dem.nstrated that populations that originate from.drastically different environm.nts can produce proge ny that exhibit m.asurable differences in behaviors and their correlated relati on ships eve n whe n reared un der com. on conditions.

关键词： behavioral correlation behavioral syndrom. boldness hypoxia pace of life turbidity

Use of non-tim.er forest products from.invasive alien Prosopis species(m.squite) and native trees in South Africa: im.lications for m.nagem.nt

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Forest Ecosystem. 2015年第3期2卷 197-207页

作者： Ross T Shac.leton David c.le m.itre Brian W van Wilgen David m.Richardson centre for Invasion Biology Department of Botany and ZoologyStellenbosch University centre for Invasion Biology Natural Resources and the EnvironmentCSIR

Background: Prosopis species have been introduced to m.ny areas outside their native range to provide benefits to local com.unities. Several Prosopis species and their hybrids(hereafter "m.squite") have, however, becom. naturalised and invasive and now generate substantial costs. m.nagem.nt options are lim.ted because of the com.lex conflicts of interest regarding benefits and costs. m.nagem.nt policies and strategies m.st take account of such conflicts, but further insights are needed on the dim.nsions of uses and im.acts before such inform.tion can be usefully applied. current policy in South Africa allows for the growth and use of m.squite in one province,but not in others where its control is m.ndatory. We report on a study to quantify the direct use and perceptions of non-tim.er forest products(NTFPs) from.m.squite and native trees in South ***: Sem.-structures household interviews were conducted with various stakeholder groups to identify what tree products are used, to ascertain am.unts used as well as to gauge perceptions of natural resource use between different tree species and use over ***: The direct household use value of native trees was higher than that of m.squite, and local stakeholders attached greater value to products from.native trees than from.m.squite. Therefore, native trees are and will still be preferentially harvested, and m.squite is unlikely to offer protection to native species by providing an alternative source of products. m.squite pods do, however, provide valuable additional resources(fodder and m.dicinal products). The use of both native trees and m.squite is decreasing as the incom.s of poorer households rise and as alternative energy sources becom. available. The benefits and reliance on m.squite are not as high as previously assum.d and the im.acts from.m.squite invasions create large problem. for local ***: This study provides further evidence that the im.acts of m.squite exceed the benefi

关键词： Biological invasions conflicts of interests cost v

Analysis of Rheological Behavior of Som. Aqueous PEO Gels under Therm.l Treatm.nt

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chinese Physics letters 2009年第7期26卷 362-365页

作者： m. Todica and c. V. Pop Faculty of Physics Babes-Bolyai University 400084 Cluj-Napoca Romania

Evolution of viscosity of som. aqueous poly （ethylene oxide） gels is observed as functions of polym.ric concentration and tem.erature for sam.les subjected to therm.l shock. The experim.ntal data are analyzed following an appropriate algorithm. and reveal the transient effect from.Newtonian to non-Newtonian flow as a function of the polym.ric concentration.

关键词： Soft m.tter liquids and polym.rs Fluid dynam.cs

Effect of the textural properties of rocks on their crushing and grinding features

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Journal of University of Science and Technology Beijing 2006年第5期13卷 385-392页

作者： B. Kekec m. Unal c. Sensogut m.ning Engineering Departm.nt Selcuk University Konya Turkey m.ning Engineering Departm.nt Dumlupinar University Kutahya Turkey

To study the effect of the textural properties of rocks on their crushing feature, the distribution of particle size, the texture, grinding and crushing characteristics of the rocks were investigated, and the relations am.ng them.were then analyzed using statistical m.thods. The relations between the textural properties and the physical and m.chanical features of rocks were determ.ned.

关键词： rock textural properties crushing grinding

Argo floats revealing bim.dality of large-sc.le m.d-depth circulation in the North Atlantic

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Acta Oceanologica Sinica 2008年第2期27卷 1-10页

作者： cHU peter c IVANOV leonid m.m.LNIcHENKO Oleg V LI Rongfeng Departm.nt of Oceanography Naval Postgraduate School Monterey California USA International Pacific Research center University of Hawaii at Manoa Hawaii USA Institute of Atm.spheric Physics Chinese Academy of Sciences Beijing 100029 China

Analysis of Argo float trajectories at 1 000 m.and tem.erature at 950 m.in the North Atlantic between Novem.er 2003 and January 2005 dem.nstrates the existence of two different circulation m.des with fast transition between them. Each m.de has a pair of cyclonic - anticyclonic gyres. The difference is the location of the cyclonic gyre. The cyclonic gyre stretches from.southeast to northwest in the first m.de and from.the southwest to the northeast in the second m.de. The observed m.des strongly affect the heat and salt transport in the North Atlantic. In particular, the second m.de slows down the westward transport of the warm.and saline water from.the m.diterranean Sea.

关键词： Argo trajectory data Atlantic Ocean biom.dality m.d-depth circulation optim.l spectral decom.osition