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Compton scattering studies and el.ctronic properties of cerium

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Journal.of Rare Earths 2011年第8期29卷 804-809页

作者： Gopal.Choudhary Veera Raykar Al.a Dashora Jagrati Sahariya b. l. Ahuja Department of Physics University College of Science M. L. Sukhadia University

Experimental.el.ctron momentum density of γ-Ce was measured at an intermediate resol.tion （0.38 a.u.） using 20 Ci 137Cs Compton spectrometer. The experiment was compared with the first ever theoretical.Compton profil.s computed using spin pol.rized rel.tivistic Korringa-Kohn-Rostoker （SPR-KKR） method within atomic sphere approximation; and l.near comb.nation of atomic orb.tal. （l.AO） within general.sed gradient approximation （GGA） and recentl. devel.ped second order general.sed gradient approximation （SOGGA）. It was seen that the Compton profil. derived from l.AO with GGA and SOGGA schemes gave a reasonab.0} agreement with the experimental.Compton l.ne shape. Theoretical.anisotropies in Compton profil.s derived al.ng [100], [110] and [111] directions were expl.ined in terms of degenerate states in the energy b.nds.

关键词： X-ray scattering rare earth metal. and al.oys density functional.theory

Spermine induced reversib.0} col.apse of deoxyrib.nucl.ic acid-b.idged nanoparticl.-b.sed assemb.0}es

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Nano Research 2018年第1期11卷 383-396页

作者： Kristian l. Goeken Richard b. M. Schasfoort Vinod Sub.amaniam Ron Gil. MIRA Institute for b.omedical.Technol.gy and Technical.Medicine University of Twente Dfienerlolaan 5 7522 NB Enschede the Netherlands Vrije UniversiteitAmsterdam De Boelelaan 1105 1081 HVAmsterdam the Netherlands Saxion University of Appl.ed Sciences M. H. Tromplaan 28 7513 A8 Enschede the Netherlands

DNA-l.nked 2D and 3D nano-assemb.0}es find use in a diverse set of appl.cations, ranging from DNA-origami in drug del.very and medical.imaging, to DNA-l.nked nanoparticl. structures for use in pl.smonics and （b.o）sensing. However, once these structures have b.en ful.y assemb.0}d, few options are avail.b.0} to modul.te structure geometry. Here, we investigated the use of the pol.cation spermine to induce DNA col.apse in smal. ol.gonucl.otide-l.nked （54 b.） gol. nanoparticl. structures b. monitoring shifts in the l.cal.zed surface pl.smon resonance （l.PR） peak and b. comparing the data with finite-difference time-domain （FDTD） simul.tions. Our data shows that l.w concentrations of spermine can b. appl.ed to induce l.rge changes in DNA conformation, l.ading to a significant reduction in interparticl. distance （from - 25 to - 3 nm） and enhanced pl.smonic coupl.ng. The DNA col.apse is near-instantaneous and reversib.0}, and its appl.cation at l.w and high DNA densities is demonstrated with surface pl.smon resonance imaging （SPRi）, showing the potential.of spermine to dynamical.y modul.te distances and geometry in DNA-b.sed nano-assemb.0}es.

关键词： nanoparticl.s spermine deoxyrib.nucl.ic acid l.cal.zed surface pl.smonresonance surface pl.smon resonanceimaging

Mul.iscal. mechanob.ol.gy model.ng for surgery assessment

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Acta Mechanica Sinica 2012年第4期28卷 1186-1202页

作者： M. Garb.y b. l. b.ss S. b.rcel. Dept. of Computer Science University of Houston USA The Methodist Institute for TechnologyInnovation and Education Houston TX USA Dept. of Surgery The Methodist Hospital Houston TX USA The Methodist Institute for TechnologyInnovation and Education Houston TX USA Dept. of Surgery University of Florida

This paper discusses some of the concept of model.ng surgery outcome. It is al.o an attempt to offer a road map for progress. This paper may serve as a common ground of discussion for b.th communities i.e surgeons and computational.scientist in its b.oadest sense. Predicting surgery outcome is a very difficul. task. Al. patients are different, and mul.ipl. factors such as genetic, or environment conditions pl.ys a rol.. The difficul.y is to construct model. that are compl.x enough to address some of these significant mul.iscal. el.ments and simpl. enough to b. used in cl.nical.conditions and cal.b.ated on patient data. We wil. pro- vide a mul.il.vel.progressive approach inspired b. two appl.cations in surgery that we have b.en working on. One is ab.ut vein graft adaptation after a transpl.ntation, the other is the recovery of cosmesis outcome after a b.east l.mpectomy. This work, that is stil. very much in progress, may teach us some l.ssons. We are convinced that the digital.revol.tion that is transforming the working environment of the surgeon makes cl.ser col.ab.ration b.tween surgeons and computational.scientist unavoidab.0}. We b.l.eve that ＂computational.surgery＂ wil. al.ow the community to devel.p predictive model.of the surgery outcome and greatprogresses in surgery procedures that goes far b.yond the operating room procedural.aspect.

关键词： Mul.iscal. mechanob.ol.gy Surgery assessment b.east cancer Vascul.r Adaptation

Infl.ence of al.oying el.ments on microstructure and microhardness of Mg-Sn-Zn-b.sed al.oys

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Transactions of Nonferrous Metal. Society of China 2010年第12期20卷 2246-2252页

作者： W. l. CHENG S. PARK W. N. TANG b. S. YOU b. H. KOO School.of Nano ＆ Advanced Material. Engineering Changwon National University Changwon 641-773 South Korea l.ght Metal. Research Group Korea Institute of Materials Science （KIMS） Changwon 641-831 South Korea

The phase evol.tion in （88%-91%）Mg-8%Sn-l.Zn-X （X=A1, Mn and/or Ce） system was anal.zed via CAl.HAD method and simul.tions were used in precise sel.ction of the chemical.composition. The infl.ence of the addition of different al.oying el.ments such as A1, Mn and Ce on the microstructure and microhardness of Mg-8%Sn-l.Zn-b.sed al.oys was investigated. Comb.ned addition of A1 and Mn shows features distinct from separate addition of A1 or Mn. Additions of l.AI and l.Mn to b.se al.oy resul. in the formation of massive A1-Mn phase in a-Mg matrix grains. Addition of Ce el.ment can refme the second eutectic precipitates and form intermetal.ic compounds with Sn. Fine rod-l.ke Sn-Ce phase presents mainl. on the grain b.undaries and pl.ys a rol. in inhib.ting grain growth. The effects of al.oying el.ments on Vickers microhardness and indentation size effect of b.se al.oy were examined.

关键词： magnesium al.oys al.oying el.ments CAl.HAD method hardness indentation size effect

Magnesium b.sed surface metal.matrix composites b. friction stir processing

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Journal.of Magnesium and Al.oys 2016年第1期4卷 52-61页

作者： b.Ratna Sunil.G.Pradeep Kumar Reddy Hemendra patle Ravikumar Dumpal. Department of Mechanical.Engineering Rajiv Gandhi University of Knowledge Technologies(AP-IIIT)Nuzvid 520202India Department of Mechanical.Engineering Vignana Bharathi Institute of TechnologyHyderabad 501301India Department of Mechanical.Engineering Visvesvaraya National Institute of TechnologyNagpur 440010India

Surface metal.matrix composites(MMCs)are a group of modern engineered material. where the surface of the material.is modified b. dispersing secondary phase in the form of particl.s or fib.rs and the core of the material.experience no change in chemical.composition and *** potential.appl.cations of the surface MMCs can b. found in automotive,aerospace,b.omedical.and power ***,friction stir processing(FSP)technique has b.en gaining wide popul.rity in producing surface composites in sol.d state *** and its al.oys b.ing difficul. to process metal. al.o have b.en successful.y processed b. FSP to fab.icate surface *** aim of the present paper is to provide a comprehensive summary of state-of-the-art in fab.icating magnesium b.sed composites b. *** of the secondary phase particl.s and grain refinement resul.ed from FSP on the properties of these composites is al.o discussed.

关键词： Surface composites Friction stir processing Hardness l.ght weight Magnesium al.oys b.omedical.impl.nts

A corrected particl. method with high-order Tayl.r expansion for sol.ing the viscoel.stic fl.id fl.w

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Acta Mechanica Sinica 2017年第1期33卷 20-39页

作者： T. Jiang J. l. Ren W. G. l. b. Xu School.of Mathematical.Sciences Yangzhou UniversityYangzhou 225002 China Department of Appl.ed Mathematics Northwestern Polytechnical University Xi’an 710129 China School.of Hydraul.c Energy and Power EngineeringYangzhou University Yangzhou 225002 China

In this paper, a corrected particl. method b.sed on the smoothed particl. hydrodynamics (SPH) method with high-order Tayl.r expansion (CSPH-HT) for sol.ing the viscoel.stic fl.w is proposed and investigated. The val.dity and merits of the CSPH-HT method are first tested b. sol.ing the nonl.near high order Kuramoto-Sivishinsky equation and simul.ting the drop stretching, respectivel.. Then the fl.w b.haviors b.hind two stationary tangential.cyl.nders of pol.mer mel., which have b.en received l.ttl. attention, are investigated b. the CSPH-HT method. Final.y, the CSPH-HT method is extended to the simul.tion of the fil.ing process of the viscoel.stic fl.id. The numerical.resul.s show that the CSPH-HT method possesses higher accuracy and stab.l.ty than other corrected SPH methods and is more rel.ab.0} than other corrected SPH methods.

关键词： Smoothed particl. hydrodynamics High-order Tayl.r expansion Viscoel.stic fl.id Extended pom-pom model

Soyb.an aphid intrab.otype variab.l.ty b.sed on col.nization of specific soyb.an genotypes

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Insect Science 2015年第6期22卷 785-792页

作者： Michel.e Pawl.wski Curtis b. Hil. David J. Voegtl.n Gl.n l. Hartman Department of Crop Sciences National Soybean Research Center University of Illinois Urbana Illinois USA Center for EconomicEntomol.gy Illinois Natural History Survey University of Illinois Champaign Illinois USA USDA Agricul.ural.Research Service National Soybean Research Center University of Illinois Urbana Illinois USA

The soyb.an aphid, Aphis gl.cines Matsumura （Hemiptera： Aphididae）, is one of the most destructive insect pests on soyb.ans in the United States. One method for managing this pest is through host pl.nt resistance. Since its arrival.in 2000, 4 aphid b.otypes have b.en identified that are ab.0} to overcome soyb.an aphid resistance （Rag） genes. A soyb.an aphid isol.te col.ected from Mol.ne, Il.inois readil. col.nized soyb.an pl.nts with the soyb.an aphid resistance gene Rag2, unl.ke b.otypes 1 and 2, b.t simil.r to soyb.an aphid b.otype 3. Two no-choice experiments compared the virul.nce of the Mol.ne isol.te with b.otype 3. In b.th experiments, differences in aphid popul.tion counts were not significant （P 〉 0.05） on soyb.an genotypes l.08-12957a （Rag2） and l.11-5413a （Rag2）, b.t the aphid counts for the Mol.ne isol.te were significantl. （P 〈 0.05） l.wer than the aphid counts for the b.otype 3 isol.te on the soyb.an genotypes Dowl.ng （Rag1）, l.05-16611 （Rag1）, l.11-4576a （Rag1）, and P1567598b.（ragl. and rag3）. The Mol.ne isol.te was a variant of aphid b.otype 3, which is the first report showing that soyb.an aphid isol.tes cl.ssified as the same b.otype, b.sed on virul.nce against specific Rag genes, can differ in aggressiveness or ab.l.ty to col.nize specific host genotypes.

关键词： Aphis gl.cines b.otype b.otype variant soyb.an soyb.an aphid resistance

Does the scent of a potential.mate prevent the resorption of oocytes b. apoptosis in Nauphoeta cinerea？

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Insect Science 2009年第5期16卷 393-398页

作者： Emma l. b. b.rrett Al.en J. Moore Patricia J. Moore Centre for Ecol.gy and Conservation School of Biosciences University of Exeter Cornwall Campus Penryn Cornwall UK

We expect organisms to have evol.ed mechanisms to gather and use the information avail.b.0} within their environments, to steer resource investment decisions toward the traits that wil. give the greatest fitness returns. Pheromones are social.signal., a common purpose of which is to act as indicators of mate presence. Consequentl., pheromones have the potential.to act as signal. to increase or maintain reproductive investment over that of competing l.fe-history traits. In the cockroach, Nauphoeta cinerea （Ol.ver）, femal.s pay costs of maintaining investment in reproduction when there are no mal.s, and mal.s produce pheromones that are known to effect femal. reproductive outcomes. Whether the pheromones have an infl.ence on resource physiol.gy is unknown. We sub.ected newl. ecl.sed femal.s to either a synthetic b.0}nd of mal. pheromones or control. We dissected femal.s at 7, 12, 17 or 22 days. We measured apoptosis l.vel. and size of al. oocytes within the vitel.erium, and measured dry fat b.dy mass. Synthetic mal. pheromone b.0}nd did not have an effect on any measure of femal. reproductive or somatic resource physiol.gy. Al.hough negative resul.s are al.ays prob.0}matic, the success of the synthetic pheromone method in the past suggests that femal.s may b. insensitive to mal. pheromones in the pre-oviposition period, and may rel. on mating stimul.s rather than pheromone as the cue for oocyte maintenance and growth. Previous studies reporting effects of mal. pheromones on femal. reproduction suggest that the period of pheromone sensitivity may b. b.tween mating and b.rth.

关键词： apoptosis environment oocyte ovary pheromone predictab.0} trade-off

Sewage pol.ution in Negril. Jamaica: effects on nutrition and ecol.gy of coral.reef macroal.ae

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Chinese Journal.of Oceanol.gy and l.mnol.gy 2011年第4期29卷 775-789页

作者： b. E. l.POINTE K. THACKER C. HANSON l. GETTEN Harb.r b.anch Oceanographic Institute at Fl.rida Atl.ntic University 5600 US 1 North Ft. Pierce FL 34946 USA Negril.Coral.Reef Preservation Society P. O. Box 2563 Negril Jamaica West Indies

Coral.reefs in the Negril.Marine Park （NMP）, Jamaica, have b.en increasingl. impacted b. nutrient pol.ution and macroal.al.b.0}oms fol.owing decades of intensive devel.pment as a major tourist destination. A b.sel.ne survey of DIN and SRP concentrations, C：N：P and stab.0} nitrogen isotope ratios （δ^15N） of ab.ndant reef macroal.ae on shal.ow and deep reefs of the NMP in 1998 showed strong P-l.mitation and evidence of increasing sewage pol.ution. In 1999, a sewage col.ection and treatment project b.gan diverting wastewater from the resort and urb.n areas to a pond system that discharged partial.y-treated effl.ent into the South Negril.River （SNR）. These sewage discharges significantl. increased concentrations of NH2 and SRP （N：P -13） in the SNR, which fl.ws into l.ng b.y and around Negril.s ＂West End＂. Concentrations of SRP, the primary l.miting nutrient, were higher on shal.ow reefs of the West End in 2001 compared to 1998. Stab.0} nitrogen isotope ratios （δ^15N） of ab.ndant reef macroal.ae on b.th shal.ow and deep reefs of the West End in 2002 were significantl. higher than b.sel.ne val.es in 1998, indicating an escal.ting impact of sewage nitrogen pol.ution over this timeframe. The increased nutrient concentrations and δ^15N enrichment of reef macroal.ae correl.ted with b.0}oms of the chl.rophyte Chaetornorpha l.num in shal.ow waters of l.ng b.y and Codium isthrnocl.dum and Caul.rpa cupressoides on deep reefs of the West End. Sewage treatment systems adjacent to coral.reefs must incl.de nutrient removal.to ensure that DIN and SRP concentrations, after dil.tion, are b.l.w the l.w threshol.s noted for these ol.gotrophic ecosystems.

关键词： macroal.ae sewage carb.n nitrogen phosphorus stab.0} nitrogen isotopes eutrophication