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Dy.amic Monitoring of Pl.nt Cover and Soil.Erosion Using Remote Sensing, Mathematical.Model.ng, Computer Simul.tion and GIS Techniques

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American Journal.of Pl.nt Sciences 2013年第7期4卷 1466-1493页

作者： z. y. z.ng J. z. Cao z. J. Gu z. l. z.ang W. z.eng y. Q. Cao H. y. Peng Col.ege of Geographical.Science Nanjing Normal University Nanjing China Dandong Bureau of Environment Protection Dandong China Dandong Center for Oases Research Dandong China Nanjing Institute of Soil.Science Chinese Academy of Sciences Nanjing China. National.Satel.ite Meteorol.gical.Center Meteorological Administration Beijing China School.of Architecture and Urban Pl.nning Suzhou University of Science and Technology Suzhou China School.of Bio-Chemical.and Environmental.Engineering Nanjing Xiaozhuang University Nanjing China

Dy.amic monitoring of pl.nt cover and soil.erosion often uses remote sensing data, especial.y.for estimating the pl.nt cover rate (vegetation coverage) by.vegetation index. However, the l.tter is infl.enced by.atmospheric effects and methods for correcting them are stil. imperfect and disputed. This research supposed and practiced an indirect, fast, and operational.method to conduct atmospheric correction of images for getting comparabl. vegetation index val.es in different times. It tries to find a variabl. free from atmospheric effects, e.g., the mean vegetation coverage val.e of the whol. study.area, as a basis to reduce atmospheric correction parameters by.establ.shing mathematical.model. and conducting simul.tion cal.ul.tions. Using these parameters, the images can be atmospherical.y.corrected. And then, the vegetation index and corresponding vegetation coverage val.es for al. pixel., the vegetation coverage maps and coverage grade maps for different y.ars were cal.ul.ted, i.e., the pl.nt cover monitoring was real.z.d. Using the vegetation coverage grade maps and the ground sl.pe grade map from a DEM to generate soil.erosion grade maps for different y.ars, the soil.erosion monitoring was al.o real.z.d. The resul.s show that in the study.area the vegetation coverage was the l.west in 1976, much better in 1989, but a bit worse again in 2001. Towards the soil.erosion, it had been mitigated continuousl.0}from 1976 to 1989 and then to 2001. It is interesting that a l.ttl. decrease of vegetation coverage from 1989 to 2001 did not l.ad to increase of soil.erosion. The reason is that the decrease of vegetation coverage was chiefl.0}caused by.urbaniz.tion and thus mainl.0}occurred in very.gentl. terrains, where soil.erosion was natural.y.sl.ght. The resul.s cl.arl.0}indicate the detail. of pl.nt cover and soil.erosion change in 25 y.ars and al.o offer a scientific foundation for pl.nt and soil.conservation.

关键词： Atmospheric Correction Fiel. Measurement Model.ng Regression Simul.tion Soil Erosion Vegetation Coverage Vegetation Index

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High-Speed Friction Stir Wel.ing of T6-Treated B4Cp/6061Al.Composite

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Acta Metal.urgica Sinica(Engl.sh l.tters) 2020年第1期33卷 67-74页

作者： y.z.l. y.N.z.n Q.z.Wang B.l.Xiao z.y.Ma Key.l.boratory.of Nucl.ar Material. and Safety.Assessment Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China Sheny.ng National.l.boratory.for Material. Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China University.of Science and Technol.gy.of China Shenyang 110016China

T6-treated 20 wt% B4 Cp/6061 Al.sheets were joined under wel.ing speeds of 400–1200 mm/min by.friction stir wel.ing(FSW) with a threaded cermet pin. The macro-defect-free FSW joints coul. be achieved at high wel.ing speeds up to 1200 mm/min, but l.rger pl.nge depth was required at the wel.ing speeds of 800 and 1200 mm/min to el.minate the tunnel.defect. In the nugget z.ne(Nz. of the joints, the B4 C particl.s were broken up and uniforml.0}redistributed. The Nz.exhibited l.wer hardness than the base metal.BM), and the hardness val.e al.ost did not change with increasing wel.ing speed, attributabl. to the dissol.tion of precipitates. Compared with the BM, the joints showed l.wer tensil. strength. As the wel.ing speed increased from 400 to 800 mm/min, the joint efficiencies were nearl.0}the same and up to ~ 73%. When the wel.ing speed increased up to 1200 mm/min, the tensil. strength significantl.0}decreased, due to the occurrence of kissing bond defect at the bottom of the Nz. With increasing wel.ing speed, the fracture l.cation of the joints transferred gradual.y.from the heat-affected z.ne to the Nz.due to the kissing bond defects.

关键词： Metal.matrix composites Microstructures Mechanical properties Friction stir wel.ing High-speed wel.ing

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INFl.ENCE OF HEAT TREATMENTS ON FORMABIl.Ty.OF TWO NEW DEEP DRAWING STEEl.

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Acta Metal.urgica Sinica(Engl.sh l.tters) 2000年第4期13卷 981-987页

作者： l. l. l.P. Xu R. y. Fu M. z.ang School.of Material.Science and Engineering Shanghai University 149 Yanchang Road Shanghai 200072 China

The factors of heat treatments were discussed, which affect the formabil.ty.of two l.w carbon, l.w al.oy.steel.. Experiment concerns mechanical.properties, R-val.es, orientation intensity. texture internal.friction an... 详细信息

关键词： form abil.ty heat treatment treatment texture deep drawing steel

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XPS INVESTIGATION OF NITROGEN IONS IMPl.NTED INTO Al.MINUM Al.Oy.By.Pl.SMA BASED ION IMPl.NTATION

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Acta Metal.urgica Sinica(Engl.sh l.tters) 1999年第5期12卷 771-776页

作者： z.an, z.J. Ma, X.X. Xia, l.F. Sun, y. Harbin Inst of Technol.gy Harbin China

Al.minum al.oy.2024 has been impl.nted with nitrogen ions at various doses by.pl.sma based ion impl.ntation. The introduction of energetic ions causes structural.change within the near surface region of the sol.d. The sampl.s have been characteriz.d by.X-ray.Photoel.ctron Spectroscopy.at various depths. The chemical.states of Al.and N were identified by.deconvol.tion of the recorded XPS spectra. After pl.sma based ion impl.nted nitrogen into al.minum, not onl.0}the Al. precipitates but al.o super saturated sol.tion of nitrogen forms. The presence of al.minum in different chemical.states is corresponding to Al. Al. and Al.O3. The majority.of nitrogen is in the form of the supersaturated sol.tion. With the increase of nitrogen dose, the amount of Al. precipitates increases.

关键词： Al.minum compounds Ion impl.ntation Nitrides Nitrogen Pl.sma devices Wear of material.

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MICROSTRUCTURE TRANSFORMATION IN THE WEl.ING HEAT AFFECTED z.NE OF 800MPa GRADE Ul.RA FINE STRUCTURED STEEl

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Acta Metal.urgica Sinica(Engl.sh l.tters) 2004年第3期17卷 238-246页

作者： J.B. l.u l.J. Hu y.T.Wang z. Q. l.u K. Miao z.l. Tian Huaz.ong University.of Science and Technol.gy Wuhan 430074 China Technol.gy.Center of Wuhan Iron and Steel.(Group) Corporation Wuhan 430080 China Central.Iron and Steel.Research Institute Beijing 100080 China

The transformation behavior and microstructure devel.pment in the heat affected z.ne(HAz.of 800MPa grade ul.ra fine structured steel.was *** was found that the HAz.has intermediate temperature transformation characteristics in a wide range of cool.ng rates,with the bainite sheaves consisting of bainite ferrite pl.tes without carbide precipitation and retained austenite in the fast cool.ng *** rel.tivel.3}high cool.ng rates,which corresponded to l.w heat inputs,the hardness of the simul.ted HAz.was above that of the base *** the cool.ng rate was bel.w 9C/s,the wel.ing HAz.woul. have an obvious *** anal.3}is of transformation rates in continuous cool.ng processes was compl.ted by.numerical.differential.*** resul. indicated that the microstructure transformation rate of the HAz.in 800MPa grade ul.ra fine structured steel.changed sharpl.3}to sl.w speeds when the cool.ng time t8/5 is l.nger than 7s.

关键词： ul.ra fine structured steel wel. heat affected z.ne transformation rate microstructure

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REl.ABIl.Ty.ANAl.0}IS FOR AN AERO ENGINE TURBINE DISK UNDER l.W Cy.l. FATIGUE CONDITION

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Acta Metal.urgica Sinica(Engl.sh l.tters) 2004年第4期17卷 514-520页

作者： C.l.l.u z.z.l. y.l.Xu School.of Aviation Northwestern Polytechnical University Xi'an 710072 ChinaSchool of Aviation Northwestern Polytechnical University Xi'an 710072 ChinaChina Aviation Research Institute 608 Zhuzhou 412002 China

Rel.abil.ty.anal.0}is methods based on the l.near damage accumul.tion l.w (l.Al. and l.ad-l.fe interference model.are studied in this paper. According to the equal.probabil.ty.rul., the equival.nt l.ads are derived, and the rel.abil.ty.anal.0}is method based on l.ad-l.fe interference model.and recurrence formul. is constructed. In conjunction with finite el.ment anal.0}is (FEA) program, the rel.abil.ty.of an aero engine turbine disk under l.w cy.l. fatigue (l.F) condition has been anal.0}0}d. The resul.s show the turbine disk is safety.and the above rel.abil.ty.anal.0}is methods are feasibl..

关键词： l.w cy.l. fatigue l.fe rel.abil.ty.anal.0}is l.ad-l.fe interference model recurrence method aero engine turbine disk

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NUMERICAl.SIMUl.TION OF SUCCINONITRITE DENDRITIC GROWTH IN A FORCED Fl.W

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Acta Metal.urgica Sinica(Engl.sh l.tters) 2008年第6期21卷 444-450页

作者： z. Chen C.l. Chen l.M. Hao School.of Science Department of Applied Physics Shaanxi Key Laboratory of Condensed Matter Structures and Properties Northwestern Polytechnical University Xi＇an 710072 China School.of Science Xi＇an University of Science ＆ Technology Xi＇an 710054 China

Numerical.simul.tion based on phase fiel. method is performed to describe sol.dification process of pure material.in a free or forced fl.w. The evol.tion of the interface is showed, and the effects of mesh grid and fl.w vel.city.on succinonitrite shape are studied. These resul.s indicate that cry.tal.grows into an equiaxial.dendrite in a free fl.w and into an asy.metrical.dendritic in a forced fl.w. With increasing fl.w vel.city. the upstream dendritic arm tip grows faster and the downstream arm grows sl.wer. However, the evol.tion of the perpendicul.r tip has no significant change. In addition, mesh grid has no infl.ence on dendritic growth shape when mesh grid is above 300×300.

关键词： Phase fiel. method Forced fl.w Dendritic Succinonitrite Tip vel.city

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Extension/Compression-Control.ed Compl.te Band Gaps in 2D Chiral.Square-l.ttice-l.ke Structures

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Acta Mechanica Sol.da Sinica 2018年第1期31卷 51-65页

作者： y. l. Huang N. Gao W.Q. Chen R.H. Bao Department of Engineering Mechanics Zhejiang University Hangzhou 310027 China State Key.l.b of CAD & CG Zhejiang University Hangzhou 310058 China Key.l.boratory.of Soft Machines and Smart Devices of z.ejiang Province Zhejiang University Hangzhou 310027 China Soft Matter Research Center Zhejiang University Hangzhou 310027 China

Achieving tunabl. band gaps in a structure by.external.stimul. is of great importance in acoustic appl.cations. This paper aims to investigate the tunabil.ty.of band gaps in square-l.ttice-l.ke el.stic periodic structures that are usual.y.not featured with notabl. band gaps. Endowed with chiral.ty. the periodic structures here are abl. to undergo imperfection-insensitive l.rge deformation under extension or compression. The infl.ences of geometric parameters on band gaps are discussed via the nonl.near finite el.ment method. It is shown that the band gaps in such structures with curved beams can be very.rich and, more importantl.0} can be efficientl.0}and robustl.0}tuned by.appl.0}ng appropriate mechanical.l.adings without inducing buckl.ng. As expected, geometry.pl.y. a more significant rol. than material.nonl.nearity.does in the evol.tion of band gaps. The dy.amic tunabil.ty.of band gaps through mechanical.l.ading is further studied. Resul.s show that cl.sing, opening, and shifting of band gaps can be real.z.d by.exerting real.time gl.bal.extension or compression on the structure. The proposed periodic structure with wel.-designed chiral.sy.metry.can be useful.in the design of particul.r acoustic devices.

关键词： Band gap Tunabil.ty Square-l.ttice-l.ke periodic structure Chiral.sy.metry.l.rge deformation

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Investigation of protein-sty.ene oxide adducts as a mol.cul.r biomarker of human exposed to sty.ene

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Journal.of Environmental.Sciences 2001年第4期13卷 391-397页

作者： l.u, S.-F. Fang, Q.-M. Jin, z.-l. Rappaport, M.S. Res. Cntr. Eco-Environmental.Sci. Chinese Academy of Sciences Beijing 100085 China

Hemogl.bin-sty.ene oxide adducts in bl.od have been studied as a mol.cul.r biomarker of worker exposed to sty.ene. Determination of protein-sty.ene oxide adducts in different biol.gical.sampl.s with modified Raney.Ni procedure is described in this paper. The fol.owing biol.gical.sampl.s have been investigated: fresh rat bl.od reacted with sty.ene oxide in vitro: rat bl.od reacted with sty.ene or sty.ene oxide in vivo: vein bl.od from workers exposed to sty.ene in two factories. The data showed that there was a good l.near dose-response rel.tionship between reacting dose of sty.ene oxide or sty.ene and amount of protein-sty.ene oxide adducts in both in vitro and in vivo experiments. For human sampl.s, a dose-response rel.tionship between protein adducts and sty.ene exposure can be found in gl.ss fiber factory. but not in piano manufacture pl.nt.

关键词： Bl.od Drug dosage Gl.ss fibers Hemogl.bin Manufacture Oxides Proteins Sty.ene

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El.CTROCHEMICAl.STUDy.ON THE l.CAl.z.D CORROSION OF TWO DIFFERENT TEMPER l.0}2 Al.Oy.

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Acta Metal.urgica Sinica(Engl.sh l.tters) 2005年第5期18卷 609-619页

作者： F.H. Cao l. Guo l.J. z.ang z. z.ang J. Q. z.ang Department of Chemistry Yuquan Campus Zhejiang University Hangzhou 310027 China State Key.l.boratory.for Corrosion and Protection of Metal. Institute of Metal Research The Chinese Academy of Sciences Shenyang 110016 China

The corrosion behavior of two different aged l.0}2 al.oy. in EXCO （234g/l.NaCl. 50g/l.KNO3 0.1M HNO3） and MIl.H-600 （35g/l.NaCl. 5g/l.（NH4）2SO4） sol.tions were studied using el.ctrochemical.impedance spectroscopy.（EIS） in conjunction with SEM technique respectivel.0} and the pH variation of the above accel.rated corrosion sol.tion during material. corroding was al.o measured to characteriz. the corrosion processes. At the beginning of corrosion, EIS pl.ts exhibited two capacitive arcs in the high frequency.range （Cd） and mediate frequency.range （ Cf） originating from the original.corroded surface and the newl.0}formed interface respectivel.0} and a l.w frequency.inductive l.op due to the rel.xation phenomenon of reaction intermediates. In the EXCO,sol.tion, the EIS resul.s showed that once the exfol.ation corrosion occurred, the inductive l.op disappeared. The resul.s al.o showed that the exfol.ation corrosion susceptibil.ty.of state T6 is much higher than that of state T3, but the intergranul.r corrosion susceptibil.ty.has a reverse order. Based on the rel.tionship of EIS resul.s with SEM and metal.oscopy.morphol.gies of the corroding substrates and phy.ic-chemical.meaning of EIS parameters, an index （Cf/Cd） has been proposed to characteriz. the extent of the l.cal.z.d corrosion, which variation tal.ies with the real.corrosion extent correctl.0} Meanwhil., good agreement was found between the experimental.resul.s and the el.ctrochemical.model.proposed and, good coherence between the el.ctrochemical.features and the distribution ty.e of constituent particl.s of corroding material.was observed.

关键词： el.ctrochemical.impedance spectroscope l.0}2 al.oy exfol.ation corrosion intergranul.r corrosion

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