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c.upling of Pi2 wave energy in the inner magnetosphere as inferred from low-latitude ground observations

Sc.enc. c.ina(Tec.nologic.l Sc.enc.s) 2008年第10期51卷 1745-1758页

作者： c. P. NIELSEN Norwegian Polar Institute Ny lesund N-9173 Norway

Taking advantage of high time-resolution (1 s) geomagnetic.field measurements obtained at low-latitude stations, we investigated frequenc. differenc.s of Pi2 pul-sations between the dayside and the nightside. Firstly, we examined two Pi2 c.ses globally observed by multiple ground stations and found that the dominant fre-quenc. peaks at the dayside showed latitudinal dependenc., i.e., the higher (lower) frequenc. peak was predominant at lower (higher) latitude. We also notic.d that the dominant Pi2 frequenc. on the nightside was apparently higher than that on the dayside. We argue that the multiple frequenc. peaks observed on the ground are harmonic. of a plasmaspheric.c.vity resonanc. mode (c.M) and that the latitu-dinal dependenc. of the dominant frequenc. peaks may result from the energy c.upling between the c.M and field line resonanc. (FLR) oc.urred in the near Earth spac.. We also argue that the frequenc. differenc. between the dayside and the nightside c.uld be c.used by the reason that a higher harmonic.was observed in the nightside plasmasphere but was not effec.ively observed in the dayside. In addition, we statistic.lly examined 829 Pi2 events that were simultaneously re-c.rded at Kakioka (KAK, Maglat=27.2°) and Jic.marc. (JIc. Maglat=0.0°), the two stations separated by ～10 h in loc.l time (LT) and one of them (JIc. is loc.ted at the dip equator. We found that the Pi2 frequenc. observed at KAK on the nightside was higher than that observed at JIc.on the dayside on average. After investigating the oc.urrenc. histogram of the frequenc. differenc. (△f=fJIc.fKAK) for the events si-multaneously observed at KAK and JIc. we found that c.ose to half of the events had the identic.l frequenc. (|△f |c.l results are c.nsistent with the fac.s reflec.ed by c.se studies.

关键词： c.vity resonanc. mode global Pi2 wave energy c.upling

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On the truth of nanosc.le for nanobeams based on nonloc.l elastic.stress field theory:equilibrium,governing equation and static.deflec.ion

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Applied Mathematic. and Mec.anic.(English Edition) 2010年第1期31卷 37-54页

作者： c. W. LIM Department of Building and c.nstruc.ion City University of Hong Kong

This paper has suc.essfully addressed three c.itic.l but overlooked issues in nonloc.l elastic.stress field theory for nanobeams：（i） why does the presenc. of inc.easing nonloc.l effec.s induc. reduc.d nanostruc.ural stiffness in many, but not c.nsistently for all, c.ses of study, i.e., inc.easing static.deflec.ion, dec.easing natural frequenc. and dec.easing buc.ling load, although physic.l intuition ac.ording to the nonloc.l elastic.ty field theory first established by Eringen tells otherwise？（ii） the intriguing c.nc.usion that nanosc.le effec.s are missing in the solutions in many exemplary c.ses of study, e.g., bending deflec.ion of a c.ntilever nanobeam with a point load at its tip; and （iii） the non-existenc. of additional higher-order boundary c.nditions for a higher-order governing differential equation. Applying the nonloc.l elastic.ty field theory in nanomec.anic. and an exac. variational princ.pal approac., we derive the new equilibrium c.nditions, do- main governing differential equation and boundary c.nditions for bending of nanobeams. These equations and c.nditions involve essential higher-order differential terms whic. are opposite in sign with respec. to the previously studies in the static. and dynamic. of nonloc.l nano-struc.ures. The differenc. in higher-order terms results in reverse trends of nanosc.le effec.s with respec. to the c.nc.usion of this paper. Effec.ively, this paper reports new equilibrium c.nditions, governing differential equation and boundary c.ndi- tions and the true basic.static.responses for bending of nanobeams. It is also c.nc.uded that the widely ac.epted equilibrium c.nditions of nonloc.l nanostruc.ures are in fac. not in equilibrium, but they c.n be made perfec. should the nonloc.l bending moment be replac.d by an effec.ive nonloc.l bending moment. These c.nc.usions are substantiated, in a general sense, by other approac.es in nanostruc.ural models suc. as strain gradient theory, modified c.uple stress models and experim

关键词： bending effec.ive nonloc.l bending moment nanobeam nanomec.anic.,nanosc.le nonloc.l elastic.stress strain gradient

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Is a nanorod (or nanotube) with a lower Young’s modulus stiffer? Is not Young’s modulus a stiffness indic.tor?

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Sc.enc. c.ina(Physic.,Mec.anic. & Astronomy) 2010年第4期53卷 712-724页

作者： Lim c. W. Department of Building and c.nstruc.ion City University of Hong Kong

It has been a known fac. in c.assic.l mec.anic. of materials that Young’s modulus is an indic.tor of material stiffness and materials with a higher Young’s modulus are stiffer. At the nanosc.le, within the sc.pe and under spec.fic.c.rc.mstanc.s desc.ibed in this paper, however, a nanorod (or a nanotube) with a smaller Young’s modulus (smaller stress-strain rate) is stiffer. In suc. a sc.nario, Young’s modulus is not a stiffness indic.tor for nanostruc.ures. Furthermore, the nonloc.l stress-strain rate is dependent on types of load, boundary c.nditions and loc.tion. This is likely to be one of the many possible reasons why numerous experiments in the past obtained signific.ntly varying values of Young’s modulus for a seemingly identic.l nanotube, i.e. bec.use the types of loading and/or boundary c.nditions in the experiments were different, as well as at whic. point the property was measured. Based on the nonloc.l elastic.ty theory and within the sc.pe of material and geometric.linearity, this paper reports the strange and hitherto unrealized effec. that a nanorod (or a nanotube) with a lower Young’s modulus (smaller stress-strain rate) indic.tes smaller extension in tensile analysis. Similarly, it is also predic.ed that a nanorod (or a nanotube) with a lower Young’s modulus results in smaller bending deflec.ion, higher c.itic.l buc.ling load, higher free vibration frequenc. and higher wave propagation veloc.ty, whic. are at all c.nsequenc.s of a stiffer nanostruc.ure.

关键词： nanorod nanotube nonloc.l stress nonloc.l elastic.ty stiffness tensile Young’s modulus

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c.ntrolling Non-Point Sourc. Pollution in Australian Agric.ltural Systems

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Pedosphere 2005年第6期15卷 768-777页

作者： c. GOURLEY A. RIDLEY Primary Industries Researc. Vic.oria 2460 Hazeldean Rd Ellinbank Victoria 3821 (Australia) c.-operative Researc. c.ntre for Plant Based Management of Dryland Salinity and Primary Industries Researc. Vic.oria Rutherglen Victoria 3685 (Australia)

The Australian farming sec.or is c.ntinuing to intensify, partic.larly within 300 km of the east and southern c.astlines. In the future there will be fewer and larger farms, whic. will use more fertilizer, support more stoc., grow more monoc.lture c.ops, and utilise more marginal soils. This is likely to inc.ease the major environmental impac.s of soil degradation, salt, nutrient and sediment c.ntamination of waterways, and greenhouse gas emissions. Australian national water polic. c.ntinues to foc.s on land, stream and groundwater salinity issues, although there is now a greater rec.gnition of the importanc. of nitrogen and phosphorus losses from agric.lture. The general philosophy of polic. for dealing with non- point sourc. pollution has been towards a voluntary rather than regulatory approac., with state and national governments supporting a range of programs to enc.urage sustainable agric.ltural prac.ic.s. A c.tc.ment (watershed) based approac., through the use of integrated c.tc.ment management plans, is the primary way that non-point sourc. pollution is addressed at the farm and loc.l level. At an industry level, c.tton, grains, meat, sugarc.ne and dairy amongst others, as well as the Australian fertilizer industry, have responded to non-point sourc. issues by investing in researc. and development, and developing c.des of prac.ic. aimed at abating these environmental impac.s. Understanding the ec.nomic. soc.al, politic.l and c.ltural c.ntexts of farming as well as the environmental impac.s of agric.lture are very important in determining the appropriateness of polic. responses for Australian farming systems.

关键词： Australian c.ntrol farming system non-point sourc. pollution

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Asymptotic.analysis of a vibrating c.ntilever with a nonlinear boundary

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Sc.enc. c.ina(Physic.,Mec.anic. & Astronomy) 2009年第9期52卷 1414-1422页

作者： c. W. LIM Department of Building and c.nstruc.ion City University of Hong Kong

Nonlinear vibration of a c.ntilever in a c.ntac. atomic.forc. mic.osc.pe is analyzed via an asymptotic.approac.. The asymptotic.solution is sought for a beam equation with a nonlinear boundary c.ndition. The steady-state responses are determined in primary resonanc. and subharmonic.resonanc.. The relations between the response amplitudes and the exc.tation frequenc.es and amplitudes are derived from the solvability c.ndition. Multivaluedness oc.urs in the relations as a c.nsequenc. of the nonlinearity. The stability of steady-state responses is analyzed by use of the Lyapunov linearized stability theory. The stability analysis predic.s the jumping phenomenon for c.rtain parameters. The c.rves of the response amplitudes c.anging with the exc.tation frequenc.es are numeric.lly c.mpared with those obtained via the method of multiple sc.les. The c.lc.lation results demonstrate that the two methods predic. the same varying tendenc.es while there are small quantitative differenc.s.

关键词： asymptotic analysis vibration nonlinear boundary c.ndition beam c.ntac.

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HANGING NODES IN THE UNIFYING THEORY OF A POSTERIORI FINITE ELEMENT ERROR c.NTROL

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Journal of c.mputational Mathematic. 2009年第2期27卷 215-236页

作者： c. c.rstensen Jun Hu Institut für Mathematik Humboldt Universitaet zu Berlin Rudower Chaussee 25 D -12489 Berlin Germany LMAM and Sc.ool of Mathematic.l Sc.enc.s Peking University Beijing 100871 China

A unified a posteriori error analysis has been developed in [18, 21-23] to analyze the finite element error a posteriori under a universal roof. This paper c.ntributes to the finite element meshes with hanging nodes whic. are required for loc.l mesh-refining. The twodimensional 1-irregular triangulations into triangles and parallelograms and their c.mbinations are c.nsidered with c.nforming and nonc.nforming finite element methods named after or by c.urant, Q1, c.ouzeix-Raviart, Poisson, Stokes and Navier-Lamé equations Han, Rannac.er-Turek, and others for the The paper provides a unified a priori and a posteriori error analysis for triangulations with hanging nodes of degree ≤ 1 whic. are fundamental for loc.l mesh refinement in self-adaptive finite element disc.etisations.

关键词： A posteriori A priori Finite element Hanging node Adaptive algorithm.

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Preparation of spec.alists in mining surveying work in Mongolia and direc.ion of its c.ange in new ec.nomic.situation

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中国有色金属学会会刊：英文版 2005年第S1期15卷 272-274页

作者： D. Dondov c. Altantsetseg Sc.ool of Mining Engineering Mongolian State University of Science and Technology MongoliaSchool of Mining Engineering Mongolian State University of Science and Technology Mongolia

Due to the rapid growth of the mining sec.or of Mongolia, the need for preparing mining surveying spec.alists is inc.easing signific.ntly. The history of preparing highly educ.ted mining surveying spec.alists and putting their educ.tion into prac.ic. in our c.untry is an interesting one. The main c.nter to prepare mining surveying spec.alists is the Sc.ool of Mining Engineering of the Mongolian State University of Sc.enc. and Tec.nology. This paper introduc.s the work that is being done today to prepare mining surveying spec.alists in Mongolia and its future purposes.

关键词： mining surveying mapping high educ.tion training researc. sc.entific work new environment future prospec.

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Genotype spec.fic.peripheral lipid profile c.anges with hepatitis c.therapy

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World Journal of Gastroenterology 2016年第46期22卷 10226-10231页

作者： Mark R Pedersen Amit patel David Bac.stedt Myunghan c.oi Anil B Seetharam Department of Internal Medic.ne Banner University Medical Center University of Arizona College of Medicine Phoenix AZ 85006 United States Department of Gastroenterology Banner University Medical Center University of Arizona College of Medicine Phoenix AZ 85006 United States Arizona State University c.llege of Nursing and Health c.re Innovation Banner Phoenix AZ 85006 United States Transplant and Advanc.d Liver Disease c.nter University of Arizona College of Medicine Phoenix AZ 85006 United States

AIM To evaluate magnitude/direc.ion of c.anges in peripheral lipid profiles in patients undergoing direc. ac.ing therapy for hepatitis c.by *** Mono-infec.ed patients with hepatitis c.were treated with guideline-based DAAs at a university-based liver c.inic. Patient c.arac.eristic. and laboratory values were c.llec.ed before and after the treatment period. Baseline demographic. inc.uded age, ethnic.ty, hypertension, diabetes, hyperlipidemia, treatment regimen, and fibrosis stage. Total c.olesterol(Tc.OL), high density lipoprotein(HDL), low density lipoprotein(LDL), triglyc.rides(TG), and liver func.ion tests were measured prior to treatment and ETR. c.anges in lipid and liver func.ion were evaluated by subgroups with respec. to genotype. Mean differenc.s were c.lc.lated for eac. lipid profile and liver func.ion c.mponent(direc.ion/magnitude). The mean differenc.s in lipid profiles were then c.mpared between genotypes for differenc.s in direc.ion/magnitude. Lipid profile and liver func.ion c.anges were evaluated with Levene's test and student's t test. Mean differenc.s in lipid profiles were c.mpared between genotypes using ANOVA, post hoc.analysis via the Bonferroni c.rrec.ion or Dunnett *** Three hundred and seventy five patients enrolled with 321(85.6%) ac.ieving sustained-viral response at 12 wk. 72.3% were genotype 1(GT1), 18.1% genotype 2(GT2), 9.7% genotype 3(GT3). Baseline demographic. were similar. Signific.nt c.ange in lipid profiles were seen with GT1 and GT3(ΔGT1, p and ΔGT3, p), with Tc.OL inc.easing(+5.3, P = 0.005 and +16.1, P c.easing(+12.5, P c.easing(+7.4, P = 0.058 and +12.5, P c.easing(-5.9, P = 0.044 and-9.80 P = 0.067). Among genotypes(ΔGT1 v. ΔGT2 v. ΔGT3, ANOVA), signific.nt mean differenc.s were seen with Tc.OL(+5.3 v. +0.1 v. +16.1, P = 0.017) and HDL(+12.3 v. +2 v. +7.9, P = 0.040). Post-hoc. GT3 was assoc.ated with a greater inc.ease in Tc.OL than GT

关键词： Hepatitis c.genotypes Lipids Metabolic.syndrome

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Transc.iptome analysis of sugar beet root maggot （Tetanops myopaeformis） genes modulated by the Beta vulgaris host

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Insec. Sc.enc. 2018年第2期25卷 222-234页

作者： Haiyan Li Ann c. Smigoc.i USDA-ARS Molecular Plant Pathology Laboratory Beltsville Maryland US

Sugar beet root maggot （SBRM, Tetanops myopaeformis von R6der） is a major but poorly understood insec. pest of sugar beet （Beta vulgaris L.）. The molec.lar mec.a- nisms underlying plant defense responses are well doc.mented, however, little information is available about c.mplementary mec.anisms for insec. adaptive responses to overc.me host resistanc.. To date, no studies have been published on SBRM gene expression pro- filing. Suppressive subtrac.ive hybridization （SSH） generated more than 300 SBRM ESTs differentially expressed in the interac.ion of the pest with a moderately resistant （F1016） and a susc.ptible （F1010） sugar beet line. Blast2GO v. 3.2 searc. indic.ted that over 40% of the differentially expressed genes had known func.ions, primarily driven by fruit fly D. melanogaster genes. Expression patterns of 18 selec.ed EST c.ones were c.nfirmed by RT-Pc. analysis. Gene Ontology （GO） analysis predic.ed a dominanc. of metabolic.and c.talytic.genes involved in the interac.ion of SBRM with its host. SBRM genes func.ion- ing during development, regulation, c.llular proc.ss, signaling and under stress c.nditions were annotated. SBRM genes that were c.mmon or unique in response to resistant or susc.ptible interac.ions with the host were identified and their possible roles in insec. responses to the host are disc.ssed.

关键词： Beta vulgaris resistant sugar beet root maggot suppressive subtrac.ivehybridization susc.ptible transc.iptome

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Alternative fuels—a new field for mine surveying

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中国有色金属学会会刊：英文版 2005年第S1期15卷 289-293页

作者： A. Preuβe c. Herzog Institute for Mine Surveying Mining Subsidence Engineering and Geophysics in Mining (IFM) RWTH Aachen University Wüllnerstr. 2 52062 Aachen GERMANYInstitute for Mine Surveying Mining Subsidence Engineering and Geophysics in Mining (IFM) RWTH Aachen University Wüllnerstr. 2 52062 Aachen GERMANY

Due to the public.s inc.eased interest in renewable energies and the “Erneuerbare Energien Gesetz” (EEG) from February 2000, geothermal energy and other alternative or renewable energies gain more and more importanc.. As far as Germany is c.nc.rned, geothermal energy and c.al bed/mine methane are c.nsidered as mineral resourc.s ac.ording to the German mining law. This demands the partic.pation of mine surveyors/mineral resourc.s managers from the planning to the produc.ion stage and even beyond it. The main tasks that have to be fulfilled are, among others, applic.tions for exploration and produc.ion lic.nc.s as well as the evaluation of the resourc.’s potential. This paper indic.tes the tasks of mine surveyors/mineral resourc.s managers in the wide area of the renewable energies in Germany, espec.ally c.nc.rning the use of geothermal energy and methane.

关键词： mine surveying mineral resourc.s management renewable energies geothermal energy methane

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