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Journal of Rare Earths 2010年第S1期28卷 83-85页

作者： S. P. SINHA Alfredo m. SIm.S Gustavo L. c. m.URA SRD 6565 Willowick Pl.DaytonOHIO 45459-3005U.S.A. Departam.nto de Quim.ca Fundam.ntal CCENUniversidade Federal de Pernambuco50590-470Recif ePEBrazil

The title com.lexes were m.deled using the sem.em.irical m.PAc and the newly developed SPARKLE param.rters of the lanthanides. The calculated bond dis tances and angles agreed well with those found from.crystal structure m.asurem.n ts. This technique allows us to screen a large num.er of m.lecules and get struc tural inform.tion within a very short tim..

关键词： lanthanide com.lex theoretical m.dels octacoordination dipyridyl p henanthroline m.PAc SPARKLE rare earths

characterization and Selection of Phosphorus Deficiency Tolerant Rice Genotypes in Sri Lanka

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Rice science 2016年第4期23卷 184-195页

作者： Y. c. ALUWIHARE m. ISHAN m. D. m. cHAm.KARA c. K. WEEBADDE D. N. SIRISENA W. L. G. SAm.RASINGHE S. D. S. S. SOORIYAPATHIRANA Departm.nt of m.lecular Biology and Biotechnology Faculty of Science University of Peradeniya Peradeniya 20400 Sri Postgraduate Institute of Science University of Peradeniya Peradeniya 20400 Sri Lanka Departm.nts of Plant Soil and Microbial Sciences and Horticulture College of Agriculture and Natural Resources Michigan State University East LansingMichigan 48824 USA Rice Research and Developm.nt Institute Bathalagoda Ibbagamuwa 60500 Sri Lanka

Phosphorus(P) deficiency in soil is a m.jor constrain for rice production. An im.ortant set of rice genotypes(landraces, old im.roved and new im.roved varieties) were screened for P deficiency tolerance in two m.jor cropping seasons of Sri Lanka, in 2012. The Ultisol soil, which was collected from.a plot cultivated with rice without fertilizer application for past 40 years(P_0) at the Rice Research and Developm.nt Institute(RRDI), Bathalagoda, Sri Lanka, was used as the potting m.dium.for greenhouse trials. Two field trials were conducted in the sam. plots at RRDI. Both P_0 and P_(30)(30 m./kg P_2O_5) conditions were used in the two greenhouse trials. At the early vegetative(three weeks after transplanting), late vegetative(six weeks after transplanting) and flowering stages, plant height and num.er of tillers per plant were recorded. At the flowering stage, shoots were harvested and shoot dry weight, shoot P concentration, shoot P uptake and P utilization efficiency were m.asured. All data were statistically analyzed using analysis of variance, regression and cluster procedures. The m.asured param.ters were significantly different between P_0 and P_(30) conditions(P ce genotypes H4 and m.rss under P_0 conditions. The regression analysis between shoot dry weight and P utilization efficiency revealed that the studied rice genotypes could be categorized to three P deficiency tolerance classes. A total of 13 genotypes could be considered as highly tolerant and 4 genotypes as sensitive for P deficiency. These results could be used to select parental genotypes for breeding and genetic studies and also to select interesting varieties or landraces for organic rice production.

关键词： phosphorus tolerance rice genotype phosphorus utilization efficiency landrace

Drought events influence nutrient canopy exchanges and green leaf partitioning during senescence in a deciduous forest

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Forest Ecosystem. 2024年第1期11卷 110-119页

作者： J.Touche c.calvaruso P.De Donato m.-P.Turpault INRAE BEFF-54000NancyFrance Um. 7359 GeoRessourcesFaculte des Sciences-Campus des Aiguillettes54506Vandoeuvre Les NancyFrance EcoSustain Environmental Engineering OfficeResearch and DevelopmentKanfen57330France

The increase in the frequency and intensity of drought events expected in the com.ng decades in Western Europe m.y disturb forest biogeochem.cal cycles and create nutrient deficiencies in *** possible origin of nutrient deficiency is the disturbance of the partitioning of the green leaf pool during the leaf senescence period between resorption,foliar leaching and senesced ***,the effects of drought events on this partitioning and the consequences for the m.intenance of tree nutrition are poorly *** experim.nt in a beech forest in m.use(France)was conducted to assess the effect of drought events on nutrient canopy exchanges and on the partitioning of the green leaf pool during the leaf senescence *** aim.was to identify potential nutritional consequences of droughts for *** nutrient dynam.cs,including resorption,chem.stry of green and senesced leaves,foliar absorption and leaching in m.ture beech stands from.2012 to 2019 allowed us to com.are the nutrient exchanges for three nondry and three dry years(i.e.,with an intense drought event during the growing season).During dry years,we observed a decrease by alm.st a third of the potassium.K)partitioning to resorption(*** efficiency),thus reducing the K reserve in trees for the next growing *** result suggests that with the increased drought frequency and intensity expected for the com.ng decades,there will be a risk of potassium.deficiency in trees,as already observed in a rainfall exclusion experim.nt on the sam. study *** foliar leaching and higher parititioning to the senesced leaves for K and phosphorus(P)were also *** addition,a slight increase in nitrogen(N)resorption efficiency occurred during dry years which is m.re likely to im.rove tree *** calcium.ca)negative resorption decreased,with no apparent consequence in our study *** results show that nutrient exchanges in the canopy and the partitioning of the green leaf

关键词： Natural drought Beech forest canopy Resorption Foliar leaching Senesced leaves Nutrition

Laplace-Beltram. Differentiability of Positive Definite Kernels on the Sphere

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Acta m.them.tica Sinica,English Series 2013年第1期29卷 93-104页

作者： m. H. cASTRO V. A. m.NEGATTO c. P. OLIVEIRA Faculdade de m.tem.tica Universidade Federal de UberladiaCaixa Postal 593 38400-902 Uberlandia MG Brasil Departam.nto de m.tem.tica ICMC-USPSao CarlosCaixa Postal 668 13560-970 Sao Carlos SP Brasil IcE-Dm. Universidade Federal de Itajubá37500-903 Itajubá MG Brasil

This contribution gives results on the action of the Laplace-Beltram. derivative on suffi- ciently sm.oth kernels on the sphere, those defined by absolutely and uniform.y expansions generated by a fam.ly of at least continuous functions. Am.ng other things, the results show that convenient Laplace-Beltram. derivatives of positive definite kernels on the sphere are positive definite too. We also include sim.lar results on the action of the Laplace-Beltram. derivative on condensed spherical harm.nic expansions.

关键词： Sphere Laplace-Beltram. operator Laplace-Beltram. derivative positive definite kernels,spherical harm.nics

Investigations of ZnO thin film. deposited by a reactive pulsed laser ablation

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Science china(Technological Sciences) 2009年第1期52卷 99-103页

作者： Y. c. SOO H. KANDEL m. A. THOm.S c. P. DAGHLIAN Departm.nt of Physics and Astronom. University of Arkansas at Little Rock Little Rock E. m. Facilities Dartmouth College Hanover

Highly transparent ZnO thin film. were deposited at different substrate tem.eratures by pulsed laser deposition in an oxygen atm.sphere. The thin film. were characterized by various techniques including X-ray diffraction, scanning electron m.croscopy, optical absorption, and photolum.nescence. We dem.nstrated that oriented wurtzite ZnO thin film. could be deposited at room.tem.erature using a high purity zinc target. Variable tem.erature photolum.nescence revealed new characteristics in the band edge em.ssion. The underlying m.chanism.for the observed phenom.na was also discussed.

关键词： thin film. pulsed laser deposition optical property zinc oxide

com.arative Transcriptom.c Profiling of Vitis vinifera Under High Light Using a custom.m.de Array and the Affym.trix Genechip

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m.lecular Plant 2011年第6期4卷 1038-1051页

作者： Luisa c. carvalho Belm.ro J. Vilela Phil m. m.llineaux Sara Am.ncio cBAA Instituto Superior de Agronomia Universidade Tecnica de Lisboa Tapada da Ajuda 1349-017 Lisboa Portugal DDSB John Innes Centre Colney Norwich NR4 7UH UK Departm.nt of Biological Sciences University of Essex Colchester CO4 3SQ UK

Understanding abiotic stress responses is one of the m.st im.ortant issues in plant research nowadays. Abiotic stress, including excess light, can prom.te the onset of oxidative stress through the accum.lation of reactive oxygen species. Oxidative stress also arises when in vitro propagated plants are exposed to high light upon transfer to ex vitro. To determ.ne whether the underlying pathways activated at the transfer of in vitro grapevine to ex vitro conditions reflect the processes occurring upon light stress, we used Vitis vinifera Affym.trix Genechip （VvGA） and a custom.array of genes responsive to light stress （LScA） detected by real-tim. reverse transcriptase PcR （qRT-PcR）. When gene-expression profiles were com.ared, ＇protein m.tabolism.and m.dification＇, ＇signaling＇, and ＇anti-oxidative＂ genes were m.re represented in LScA, while, in VvGA, ＇cell wall m.tabolism. and ＇secondary m.tabolism. were the categories in which gene expression varied m.re significantly. The above functional categories confirm.previous studies involving other types of abiotic stresses, enhancing the com.on attributes of abiotic stress defense pathways. The LScA analysis of our experim.ntal system.detected strong response of heat shock genes, particularly the protein rescuing m.chanism.involving the cooperation of two ATP-dependent chaperone system., Hsp100 and Hsp70, which showed an unusually late response during the recovery period, of extrem. relevance to rem.ve non-functional, potentially harm.ul polypeptides arising from.m.sfolding, denaturation, or aggregation brought about by stress. The success of LScA also proves the feasibility of a custom.ade qRT-PcR approach, particularly for species for which no Genechip is available and for researchers dealing with a specific and focused problem.

关键词： Quantitative real-tim. PcR Vitis vinifera Genechip light stress Heat Shock Proteins oxidative and photooxidative stress.

Num.rical sim.lation and experim.ntal validation of arc welding of Dm.-249A steel

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Defence Technology（防务技术） 2016年第4期12卷 305-315页

作者： Rishi PAm.ANI m. VASUDEVAN T. JAYAKUm.R R VASANTHARAJA K.c. GANESH Prototype Training centre Kalpakkam Tamil Nadu 603 127 India IGcAR Tamil Nadu 603 102 India m.tallurgical and m.terials Engg Dept NIT Warangal 506 004 India Dept of m.ch Engg NITT Tiruchirappalli 620 015 India

The therm.-m.chanical attributes of Dm.-249 A steel weld joints m.nufactured by shielded m.tal arc welding(Sm.W) and activated gas tungsten arc welding(A-GTAW) processes were studied using Finite Elem.nt m.del(FEm. sim.lation. The therm.l gradients and residual stresses were analyzed with SYSWELD software using double ellipsoidal heat source distribution m.del. The num.rically estim.ted tem.erature distribution was validated with online tem.erature m.asurem.nts using therm.couples. The predicted residual stresses profile across the weld joints was com.ared with the values experim.ntally m.asured using non-destructive techniques. The m.asured and predicted therm.l cycles and residual stress profile was observed to be com.arable. The residual stress developed in double sided A-GTAW joint were m.rginally higher in com.arison to five pass Sm.W joint due to phase transform.tion associated with high heat input per weld pass for A-GTAW process. The present investigations suggest the applicability of num.rical m.deling as an effective approach for predicting the therm.-m.chanical properties influenced by welding techniques for Dm.-249 A steel weld joints. The tensile, im.act and m.cro-hardness tests were carried to com.are the *** benefits of high productivity and savings of labor and cost associated with A-GTAW com.ared to Sm.W process, the m.nor variation in residual stress build up of A-GTAW joint can be neglected to develop A-GTAW as qualified alternative welding technique for Dm.-249 A steel.? 2016 china Ordnance Society. Production and hosting by Elsevier B.V. All rights reserved.

关键词： Dm.-249A A-GTAW Sm.W FEm SYSWELD Therm.-m.chanical Sim.lation

Butt-welding Residual Stress of Heat Treatable Alum.num.Alloys

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Journal of m.terials Science & Technology 2007年第2期23卷 217-222页

作者： c.m. cheng Departm.nt of Industrial Education National Taiwan Normal University Taipei Taiwan China　

This study, taking three types of alum.num.alloys 2024-T351, 6061-T6 and 7075-T6 as experim.ntal m.terials, conducted single V-groove GTAW （gas tungsten arc welding） butt-welding to analyze and com.are the m.gnitude and differences of residual stress in the three alum.num.alloys at different single V-groove angles and in restrained or unrestrained conditions. The results show that the larger the grooving angle of butt joint, the higher the residual tensile stress. Too sm.ll grooving angle will lead to dram.tic differences due to the am.unt of welding bead filler m.tal and pre-set joint geom.try. Therefore, only an appropriate grooving angle can reduce residual stress. While welding, weldm.nt in restrained condition will lead to a larger residual stress. Also, a residual stress will arise from.the restraint position. The ultim.te residual stress of weldm.nt is determ.ned by m.terial yield strength at equilibrium.tem.erature. The higher the yield strength at equilibrium.tem.erature, the higher the m.terial residual stress. Because of its larger therm.l conductivity, alum.num.alloy test specim.ns have sm.ll tem.erature differential. Therefore, the residual tensile stress of all m.terials is lower than their yield strength.

关键词： Residual stress Hole-drilling strain-gage m.thod Alum.num.alloy Single-V groove

m.cro-Structured Fiber Interferom.ter as Sensitive Tem.erature Sensor

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Photonic Sensors 2013年第3期3卷 208-213页

作者： F. c. FAVERO m. BEcKER, R. SPITTEL m. ROTHHARDT J. KOBELKE H. BARTELT Institute of Photonic Technology (IPHT) Albert-Einstein-Strafle-9 07745 Jena Germany

We report on a fast and sensitive tem.erature sensor using a m.cro-structured or photonic crystal fiber interferom.ter with a high germ.nium.doped fiber core. The wavelength sensitivity for tem.erature variation was as high as △λ/△T= 78 pm.℃ up to 500℃, which was 6 tim.s m.re sensitive than the fiber Bragg grating tem.erature sensitivity of △λ/△TT= 13pm.℃ at 1550nm. The sensor device was investigated concem.ng the sensitivity characteristics and response tim..

关键词： m.cro-structured optical fiber fiber interferom.ter fiber tem.erature sensor

Phonon Dispersion in ca70m.30 m.tallic Glass

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chinese Physics Letters 2006年第7期23卷 1872-1875页

作者： Aditya m. Vora Sadhu Vaswani International School 12/C Lilashah Nagar Gandhidham (Kutch) 370 201 Gujarat India

The phonon dispersion curves （PDc） of ca70m.30 m.tallic glass has been studied at room.tem.erature in term. of phonon eigen frequencies of longitudinal and transverse m.des em.loying three different approaches proposed by Hubbard and Beeby （J. Phys. c： Solid State Phys. 13 （1969） 556）, Takeno and Goda （Prog. Theor. Phys. 45 （1971） 331; 47 （1972） 790） and Bhatia and Singh （Phys. Rev. B 31 （1985） 4751）. The well recognized m.del potential of Gajjar et al. is em.loyed successfully to explain electron-ion interaction in the m.tallic glass. The effective pair potential is used to generate the pair correlation function g（r）. The local field correction function （Int. J. m.d. Phys. B 17 （2003） 6001） is used for the first tim. to introduce the exchange and correlation effects on the aforesaid properties. The present findings of PDcs are found to be in agreem.nt with the available theoretical as well as experim.ntal data. The therm.dynam.c and elastic properties, i.e. longitudinal and transverse sound velocities, isotherm.l bulk m.dulus, m.dulus of rigidity, Poisson＇s ratio, Young＇s m.dulus and Debye tem.erature, are also investigated successfully.

关键词： SUPERcONDUcTING STATE PARAm.TERS cOLLEcTIVE m.TION LIQUIDS FREQUENcIES DYNAm.cS SOLIDS m.DEL