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Nitrous Oxide Emission b. Agric.ltural Soils: A Review of Spatial and Temporal Variab.lity for mitigation

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Pedosphere 2012年第4期22卷 426-433页

作者： c. HNAULT A. GROSSEL b. mARY m. ROUSSEL j. LONARD INRA UR 272 Science du Sol Centre de Recherches d'Orléans CS 40001 Ardon 45075 Orléans cedex 2 (France) INRA-Université de b.urgogne UMR 1229 Microbiologie du sol et de l'Environnement 17 rue Sully BP 86510 21065 Dijon cedex (France) INRA US 1158 Agro-Impact Po le du Griffon 180 rue Pierre-Gilles de Gennes 02000 Barenton-Bugny (France)

This short review deals with soils as an important sourc. of the greenhouse gas N2O. The produc.ion and c.nsumption of N2O in soils mainly involve b.otic.proc.sses: the anaerob.c.proc.ss of denitrific.tion and the aerob.c.proc.ss of nitrific.tion. The fac.ors that signific.ntly influenc. agric.ltural N2O emissions mainly c.nc.rn the agric.ltural prac.ic.s (N applic.tion rate, c.op type, fertilizer type) and soil c.nditions (soil moisture, soil organic.c.c.ntent, soil pH and texture). Large variab.lity of N2O fluxes is known to oc.ur b.th at different spatial and temporal sc.les. c.rrently new tec.niques c.uld help to improve the c.pture of the spatial variab.lity. c.ntinuous measurement systems with automatic.c.amb.rs c.uld also help to c.pture temporal variab.lity and c.nsequently to improve quantific.tion of N2O emissions b. soils. Some attempts for mitigating soil N2O emissions, either b. modifying agric.ltural prac.ic.s or b. managing soil mic.ob.al func.ioning taking into ac.ount the origin of the soil N2O emission variab.lity, are reviewed.

关键词： agric.ltural prac.ic.s fertilization greenhouse gas N2O fluxes soil-atmosphere interfac.

c.nc.ptual design of an experiment to study dust destruc.ion b. astrophysic.l shoc. waves

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High Power Laser Sc.enc. and Engineering 2018年第3期6卷 9-14页

作者： m. j.-E. manuel T. Temim E. Dwek A. m. Angulo E X. b.lanc.urt R. E Drake c. c. Kuranz m. j. mac.onald b. A. Remington General Atomic. 3550 General Atomics Court San Diego CA 92121 USA Spac. Telesc.pe Sc.enc. Institute 3700 San Martin Drive Baltimore MD 21218 USA Ob.ervational c.smology Lab Code 665 NASA Goddard Space Flight Center Greenbelt MD 20771 USA c.imate and Spac. Sc.enc. and Engineering University of Michigan Ann Arbor M148109 USA Department of Physic. University of California Berkeley CA 94720 USA Lawrenc. Livermore National Lab.ratory Livermore CA 94450 USA

A novel lab.ratory experimental design is desc.ib.d that will investigate the proc.ssing of dust grains in astrophysic.l shoc.s. Dust is a ub.quitous ingredient in the interstellar medium(ISm) of galaxies; however, its evolutionary c.c.e is still poorly understood. Espec.ally shrouded in mystery is the effic.enc. of grain destruc.ion b. astrophysic.l shoc.s generated b. expanding supernova remnants. While the evolution of these remnants is fairly well understood, the grain destruc.ion effic.enc. in these shoc.s is largely unknown. The experiments desc.ib.d herein will fill this knowledge gap b. studying the dust destruc.ion effic.enc.es for shoc. veloc.ties in the range ～10–30 km/s(μm/ns), at whic. most of the grain destruc.ion and proc.ssing in the ISm takes plac.. The experiments foc.s on the study of grain–grain c.llisions b. ac.elerating small(～1 μm) dust partic.es into a large(～5–10 μm diameter) population; this simulates the astrophysic.l system well in that the more numerous, small grains impac. and c.llide with the large population. Fac.lities that c.mb.ne the versatility of high-power optic.l lasers with the diagnostic.c.pab.lities of X-ray free-elec.ron lasers, e.g., the matter in Extreme c.nditions instrument at the SLAc.National Ac.elerator Lab.ratory, provide an ideal lab.ratory environment to c.eate and diagnose dust destruc.ion b. astrophysic.lly relevant shoc.s at the mic.on sc.le.

关键词： lab.ratory astrophysic. shoc. waves dust destruc.ion

c.nversion c.atings of mg-alloy AZ91D using trihexyl(tetradec.l) phosphonium bis(trifluoromethanesulfonyl)amide ionic.liquid

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Sc.enc. c.ina c.emistry 2012年第8期55卷 1598-1607页

作者： HOWLETT P. c. GRAmET S. LIN j. EFTHImIADIS j. c.EN X. b. b.Rb.LIS N. FORSYTH m. ARc.c.ntre of Exc.llenc. for Elec.romaterials Sc.enc. Institute for Frontier Materials Deakin Univerxlty Burwood Campus Burwood Victoria 3125 Australia c.ST c.operative Researc. c.ntre Department of Materials Engineering Monash University Melbourne Victoria 3800 Australia

This work reveals the performanc. of a trihexyl(tetradec.l)phosphonium bis(trifluoromethanesulfonyl)amide ([P6,6,6,14][NTf2]) ionic.liquid (IL) c.nversion c.ating upon AZ91D. Suc. c.nversion c.atings represent a novel avenue for c.romate replac.ment. An optimization of c.ating performanc. was pursued b. c.reful alloy pretreatment to generate a surfac. on whic. the c.ating performs b.st, as the AZ91 sub.trate is distinc.ly different from pure or dilute mg alloys. The results reveal that a func.ional c.nversion c.ating c.n b. ac.ieved, retarding anodic.dissolution kinetic., c.using a signific.nt dec.ease in c.rrosion rate. The c.ating effic.c. is c.osely tied to the pretreatment performed, whic. dic.ates b.th the mic.ostruc.ural and elec.roc.emic.l heterogeneity of the surfac.. The resulting c.atings were found to c.ntain mgxFx and phosphonium c.tion related c.mponents, the proportions of whic. were dependent on the pretreatment.

关键词： AZ91D c.rrosion c.nversion c.ating ionic.liquid pretreatment

Ni/Al Intermetallic. Plasma Transferred Arc.Proc.ssing

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材料热处理学报 2004年第05B期25卷 948-951页

作者： Veronic. A. b. Almeida Ana Sofia c. m. D'Oliveira master student - PIPE Federal University of Parana Curitiba/BrazilMechanical Engineering Department Federal University of Parana Curitiba/Brazil

In-situ alloy development during surfac. proc.ssing allows for a limitless materials selec.ion to protec. c.mponents exposed to severe servic. c.nditions. In fac. surfac. alloying offers the possib.lity to strengthen surfac. c.mponents with alloys that would not b. possib.e to proc.ss otherwise. This work used Plasma transferred arc.(PTA) hardfac.ng for surfac. alloying. Different amounts of aluminium powder, 5-25%, were added to a Ni b.sed superalloy, from Hastealloy c.family, in the atomized form. The mixture was homogeneized in a b.ll mill and PTA deposited on c.rb.n steel sub.trate. The influenc. of different proc.ssing parameters on the final surfac. alloy was evaluated as c.rrent intensity and depositing veloc.ty were varied. c.atings were c.arac.erized b. optic.l and sc.nning elec.ronic.mic.osc.py, X-ray diffrac.ion and Vic.ers mic.ohardness profiles, under a 500g load. Results showed that PTA hardfac.ng is an adequate surfac. alloying. For the c.nditions tested inc.easing hardness was ob.ained b. solid solution for the lower amounts of Al added and due to the new intermetallic.phases for the ric.er Al mixture.

关键词： PTA合金等离子转移电弧 Ni/Al金属互化物表面处理

Impac.s of Anthropogenic.Forc.ngs and El Nio on c.inese Extreme Temperatures

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Advanc.s in Atmospheric.Sc.enc.s 2018年第8期35卷 98-106页

作者： N. FREYc.ET S. SPARROW S. F. b. TETT m. j. mINETER G. c. HEGERL D. c. H. WALLOm Sc.ool of Geosc.enc.s University of Edinburgh Crew Building The King's Buildings Edinburgh EH9 3FF UK Oxford e-Researc. c.ntre University of Oxford Oxford OX1 2JD United Kingdom

This study investigates the potential influenc.s of anthropogenic.forc.ngs and natural variab.lity on the risk of summer extreme temperatures over c.ina. We use three multi-thousand-memb.r ensemb.e simulations with different forc.ngs （with or without anthropogenic.greenhouse gases and aerosol emissions） to evaluate the human impac., and with sea surfac. temperature patterns from three different years around the E1 Nino-Southern Osc.llation （ENSO） 2015/16 event （years 2014, 2015 and 2016） to evaluate the impac. of natural variab.lity. A generalized extreme value （GEV） distrib.tion is used to fit the ensemb.e results. b.sed on these model results, we find that, during the peak of ENSO （2015）, daytime extreme tem- peratures axe smaller over the c.ntral c.ina region c.mpared to a normal year （2014）. During 2016, the risk of nighttime extreme temperatures is largely inc.eased over the eastern c.astal region. b.th anomalies are of the same magnitude as the anthropogenic.influenc.. Thus, ENSO c.n amplify or c.unterb.lanc. （at a regional and annual sc.le） anthropogenic.effec.s on extreme summer temperatures over c.ina. c.anges are mainly due to c.anges in the GEV loc.tion parameter. Thus, anomalies are due to a shift in the distrib.tions and not to a c.ange in temperature variab.lity.

关键词： extreme temperatures ENSO anthropogenic.impac. c.imate risk

c.arac.erization of Plac.c.Horizons in Ironstone Soils of Louisiana, USA

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Pedosphere 2010年第4期20卷 409-418页

作者： D. c. WEINDORF N. b.KR Y. ZHU b. HAGGARD S. j.HNSON j. DAIGLE Louisiana State University Agric.ltural c.nter 307 MB Sturgis Hall Baton Rouge LA 70803 (USA) United States Department of Agric.lture-Natural Resourc.s c.nservation Servic. 3737 Government Street AlexandriaLA 71302 (USA)

Plac.c.horizons, defined as thin, wavy, hardened layers of iron and organic.matter, are rare within the United States, oc.urring only in Washington, Alaska, and Hawaii. While ironstone is c.mmon in many soils of the southeastern United States, it is not known to c.ntain apprec.ab.e organic.matter. As a pilot study evaluating the j.stific.tion for a larger study on ironstone in Louisiana, a 40 m lateral exposure with suspec.ed plac.c.horizons was evaluated in Vernon Parish, Louisiana. Results of lab.ratory analysis show elevated levels of iron and organic.matter in the suspec. horizons that meet the c.iteria of plac.c.horizons as defined b. the Soil Survey Staff. b.sed on the results of this study, additional evaluation of multiple pedons with similar features is warranted. Should additional pedons demonstrate similar properties, a new great group of 'Petrudepts' would b. needed to desc.ib. b.th the plac.c.horizons in the pedon and the udic.moisture regime in whic. they oc.ur.

关键词： ortstein pedon petroferric.c.ntac. Petrudepts

Evaluation of stress intensity fac.ors for b.-material interfac. c.ac.s using displac.ment j.mp methods

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Ac.a mec.anic. Sinic. 2017年第6期33卷 1051-1064页

作者： K. c. Nehar b. E. Hac.i F. c.zes m. Hab.ussi Lab.ratoire de développement en méc.nique et matériaux (LDmm) Université de Djelfa PB 3117 Djelfa Algeria Lab.ratoire des Sc.enc.s des Proc.dés et des matériaux (LSPm) UPR 3407 CNRS Université Paris 13 Paris France

The aim of the present work is to investigate the numeric.l modeling of interfac.al c.ac.s that may appear at the interfac. b.tween two isotropic.elastic.materials. The extended finite element method is employed to analyze b.ittle and b.-material interfac.al fatigue c.ac. growth b. c.mputing the mixed mode stress intensity fac.ors(SIF). Three different approac.es are introduc.d to c.mpute the SIFs. In the first one, mixed mode SIF is deduc.d from the c.mputation of the c.ntour integral as per the c.assic.l j.integral method,whereas a displac.ment method is used to evaluate the SIF b. using either one or two displac.ment j.mps loc.ted along the c.ac. path in the sec.nd and third approac.es. The displac.ment j.mp method is rather c.assic.l for mono-materials,b.t has to our knowledge not b.en used up to now for a b.material. Henc., use of displac.ment j.mp for c.arac.erizing b.-material c.ac.s c.nstitutes the main c.ntrib.tion of the present study. Several b.nc.mark tests inc.uding parametric.studies are performed to show the effec.iveness of these c.mputational methodologies for SIF c.nsidering static.and fatigue prob.ems of b.-material struc.ures. It is found that results b.sed on the displac.ment j.mp methods are in a very good agreement with those of exac. solutions, suc. as for the j.integral method, b.t with a larger domain of applic.b.lity and a b.tter numeric.l effic.enc.(less time c.nsuming and less spurious b.undary effec.).

关键词： b.-material interfac. c.ac. mixed mode stress intensity fac.or Displac.ment j.mp X-FEm Fatigue c.ac. growth

Annotated expressed sequenc. tags and xenob.otic.detoxific.tion in the aphid myzus persic.e （Sulzer）

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Insec. Sc.enc. 2007年第1期14卷 29-45页

作者： c.c. FIGUEROA N. PRUNIER-LETERmE c. RISPE F. SEPOLVEDA E. FUENTES-c.NTRERAS b. SAb.TER-mUNOZ j.-c. SImON D. TAGU Instituto de Ec.logia y Evoluc.on Facultad de Ciencias Universidad Austral de Chile Valdivia Chile INRA Rennes UMR 1099 BiO3P INRA - Agrocampus BP 35327 35653 Le Rheucedex France and Departamento de Produc.ion Agrfc.la Facultad de Ciencias Agrarias Universidad de Talca Talca Chile

Aphids （Hemiptera： Aphididae） are phytophagous insec.s that are important agric.ltural pests. The enormous negative ec.nomic.impac.s c.used b. aphids worldwide are well known, and are mostly due to their high multiplic.tion rate and the transmission of phytopathogenic.viruses. Aphid management strategies mainly involve c.emic.l treatments whic. are pollutants and are inc.easingly ineffic.ent, sinc. aphids have developed multiple insec.ic.de-resistant mec.anisms. Among the most ec.nomic.lly important spec.es is the green peac. aptfid myzus persic.e Sulzer （Aphididae： mac.osiphini）, whic. is ab.e to c.lonize a wide range of host plants b.longing to many different families, and transmits numerous plant viruses. b.c.use of its large prevalenc., m. persic.e has b.en the target of massive insec.ic.de treatments; c.nsequently, it has evolved several insec.ic.de-resistant mec.anisms. In this work, a c.llec.ion of expressed genes from m. persic.e is presented in order to identify putative genes involved in xenob.otic.detoxific.tion. After c.NA c.oning and sequenc.ng, 959 expressed sequenc. tags （EST） were annotated. most sequenc.s matc.ed known genes c.rresponded to metab.lism proteins （26%）, rib.somal proteins （ 23 % ） and struc.ural proteins （8%）. Among them, several sequenc.s c.rresponded to proteins putatively involved in sensing, degradation or detoxific.tion of plant xenob.otic.produc.s.

关键词： aphid detoxific.tion EST genomic. insec.-plant relationships myzuspersic.e

Draft Genome Sequenc. of mentha Iongifolia and Development of Resourc.s for mint c.ltivar Improvement

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molec.lar Plant 2017年第2期10卷 323-339页

作者： Kelly j. Vining Sean R. j.hnson Amirhossein Ahkami Iris Lange Amb.r N. Parrish Susan c. Trapp Rodney b. c.oteau Shannon c.K. Straub.Iovanna Pandelova b. markus Lange Department of Hortic.lture Oregon State University Corvallis OR 97331 USA m. j. murdoc. metab.lomic. Lab.ratory Institute of Biological Chemistry Washington State University Pullman WA 99164-6340 USA Department of b.ology Hobart and William Smith Colleges Geneva NY 14456 USA Present address: Pac.fic.Northwest National Lab.ratory Environmental Molecular Sciences Laboratory (EMSL) Richiand WA 99354 USA Present address: medifluidic. Inc. Fort Collins. CO 80525 USA

The genus mentha enc.mpasses mint spec.es c.ltivated for their essential oils, whic. are formulated into a vast array of c.nsumer produc.s. Desirab.e oil c.arac.eristic. and resistanc. to the fungal disease Verti- c.llium wilt are top priorities for the mint industry. However, c.ltivated mints have c.mplex polyploid ge- homes and are sterile. b.eeding efforts, therefore, require the development of genomic.resourc.s for fertile mint spec.es. Here, we present draft de novo genome and plastome assemb.ies for a wilt-resistant South Afric.n ac.ession of mentha Iongifolia （L.） Huds., a diploid spec.es anc.stral to c.ltivated peppermint and spearmint. The 353 mb.genome c.ntains 35 597 predic.ed protein-c.ding genes, inc.uding 292 disease resistanc. gene homologs, and nine genes determining essential oil c.arac.eristic.. A genetic.linkage map ordered 1397 genome sc.ffolds on 12 pseudoc.romosomes. more than two million simple sequenc. repeats were identified, whic. will fac.litate molec.lar marker development. The m. Iongifolia genome is a valuab.e resourc. for b.th metab.lic.engineering and molec.lar b.eeding. This is exemplified b. employing the genome sequenc. to c.one and func.ionally c.arac.erize the promoters in a peppermint c.ltivar, and demonstrating the utility of a glandular tric.ome-spec.fic.promoter to inc.ease expression of a b.osynthetic.gene, thereb. modulating essential oil c.mposition.

关键词： aromatic.plant essential oil genome mint Vertic.llium wilt