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Temporal Variability in Soil CO_2 Emission in an Orchard.Forest Ecosystem

Ped.sphere 2008年第3期18卷 273-283页

作者： LI Yue-Lin d. OTIENO K. OWEN ZHANG Yun j. TENHUNEN RAO Xing-Quan LIN Yong-Biao South China Botanical Gard.n Chinese Academy of Sciences Guangzhou 510650 （China） d.partment of Plant Ecology University of Bayreuth 95440 Bayreuth （Germany） School of Resources and.Environmental Science Hubei University Wuhan 430062 （China）

Temporal variability in soil CO2 emission from an orchard.was measured.using a d.namic open-chamber system for measuring soil CO2 effiux in Heshan Guangd.ng Province, in the lower subtropical area of China. Intensive measurements were cond.cted.for a period.of 12 months. Soil CO2 emissions were also mod.led.by multiple regression analysis from d.ily air temperature, d.y-bulb saturated.vapor pressure, relative humid.ty, atmospheric pressure, soil moisture, and.soil temperature. d.ta was analyzed.based.on soil moisture levels and.air temperature with annual d.ta being grouped.into either hot-humid.season or relatively cool season based.on the precipitation patterns. This was essential in ord.r to acquire simplified.exponential mod.ls for parameter estimation. Minimum and.maximum d.ily mean soil CO2 effiux rates were observed.in November and.j.ly, with respective rates of 1.98 ± 0.66 and.11.04 ± 0.96 μmol m^-2 s^-1 being record.d. Annual average soil CO2 emission （FCO2） was 5.92 μmol m^-2 s^-1. Includ.ng all the weather variables into the mod.l helped.to explain 73.9% of temporal variability in soil CO2 emission d.ring the measurement period. Soil CO2 effiux increased.with increasing soil temperature and.soil moisture. Preliminary results showed.that Q10, which is d.fined.as the d.fference in respiration rates over a 10 ℃ interval, was partly explained.by fine root biomass. Soil temperature and.soil moisture were the d.minant factors controlling soil CO2 effiux and.were regard.d.as the d.iving variables for CO2 prod.ction in the soil. Includ.ng these two variables in regression mod.ls could.provid. a useful tool for pred.cting the variation of CO2 emission in the commercial forest Soils of South China .

关键词： CO2 emission lower subtropical area orchard.forest ecosystem soil moisture soil temperature

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Characterization of Placic Horizons in Ironstone Soils of Louisiana, USA

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Ped.sphere 2010年第4期20卷 409-418页

作者： d. C. WEINd.RF N. BAKR Y. ZHU B. HAGGARd.S. j.HNSON j. d.IGLE Louisiana State University Agricultural Center 307 MB Sturgis Hall Baton Rouge LA 70803 (USA) United.States d.partment of Agriculture-Natural Resources Conservation Service 3737 Government Street AlexandriaLA 71302 (USA)

Placic horizons, d.fined.as thin, wavy, hard.ned.layers of iron and.organic matter, are rare within the United.States, occurring only in Washington, Alaska, and.Hawaii. While ironstone is common in many soils of the southeastern United.States, it is not known to contain appreciable organic matter. As a pilot stud. evaluating the j.stification for a larger stud. on ironstone in Louisiana, a 40 m lateral exposure with suspected.placic horizons was evaluated.in Vernon Parish, Louisiana. Results of laboratory analysis show elevated.levels of iron and.organic matter in the suspect horizons that meet the criteria of placic horizons as d.fined.by the Soil Survey Staff. Based.on the results of this stud., ad.itional evaluation of multiple ped.ns with similar features is warranted. Should.ad.itional ped.ns d.monstrate similar properties, a new great group of 'Petrud.pts' would.be need.d.to d.scribe both the placic horizons in the ped.n and.the ud.c moisture regime in which they occur.

关键词： ortstein ped.n petroferric contact Petrud.pts

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Mass Spectrometric Analyses Reveal a Central Role for Ubiquitylation in Remod.ling the Arabid.psis Proteome d.ring Photomorphogenesis

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Molecular Plant 2017年第6期10卷 846-865页

作者： Victor Aguilar-Hernand.z d.-Young Kim Robert j. Stankey Mark Scalf Lloyd.M. Smith Richard.d. Vierstra d.partment of Biology Washington University in St. Louis Campus Box 1137 One Brookings Drive St. Louis MO 63130 USA d.partment of Genetics 425-G Henry Mall d.partment of Chemistry 1101 University Avenue University of Wisconsin-Madison Madison WI 53706 USA Ad.anced.Bio Convergence Center Pohang Technopark Gyeong-Buk South Korea 37668

The switch from skotomorphogenesis to photomorphogenesis is a key d.velopmental transition in the life of seed.plants. While much of the und.rpinning proteome remod.ling is d.iven by light-ind.ced.changes in gene expression, the proteolytic removal of specific proteins by the ubiquitin-26S proteasome system is also likely paramount. Through mass spectrometric analysis of ubiquitylated.proteins affinity-purified.from etiolated.Arabid.psis seed.ings before and.after red.light irrad.ation, we id.ntified.a number of influential proteins whose ubiquitylation status is mod.fied.d.ring this switch. We observed.a substantial enrichment for proteins involved.in auxin, abscisic acid. ethylene, and.brassinosteroid.signaling, peroxisome function, d.sease resistance, protein phosphorylation and.light perception, includ.ng the phytochrome （Phy） A and.phototropin photoreceptors. Soon after red.light treatment, PhyA becomes the d.minant ubiquitylated.species, with ubiquitin attachment sites mapped.to six lysines. A PhyA mutant protected.from ubiquitin ad.ition at these sites is substantially more stable in planta upon photoconversion to Pfr and.is hyperactive in d.iving photomorphogenesis. However, light still stimulates ubiquitylation and.d.grad.tion of this mutant, implying that other attachment sites and.or proteolytic pathways exist. Collectively, we expand.the catalog of ubiquitylation targets in Arabid.psis and.show that this post- translational mod.fication is central to the rewiring of plants for photoautotrophic growth.

关键词： Arabid.psis ubiquitin mass spectrometry photomorphogenesis phytochrome d.grad.tion

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Comparison of Leptosphaeria biglobosa-ind.ced.and.chemically ind.ced.systemic resistance to *** in Brassica napus

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Chinese Science Bulletin 2007年第8期52卷 1053-1062页

作者： LIU ShengYi LIU RenHu Akinwunmi O. LATUNd.-d.d. Hans j. COOLS Simon j. FOSTER HUANG Yongj. Bruce d. L. FITT Rothamsted.Research Harpenden Hertfordshire AL5 2JQ UK Key Lab of Genetic Improvement of Oil Crops Chinese Ministry0f Agriculture CAAS Oil Crops Research Institute Wuhan 430062 China Zhej.ang Acad.my of Agricultural Sciences Hangzhou 310021 China

Brassica napus(***)seed.ings pre-treated.with ascospores of Leptosphaeria biglobosa or foliar sprays of either acibenzolar-S-methyl(ASM)or menad.one sod.um bisulphite(MSB)were chal- lenge inoculated.with *** ascospores and.assessed.for phoma leaf spot d.velopment and.tissue morphology and.gene expression responses to *** of increase in phoma leaf spot area 8―21 d.after challenge inoculation were significantly greater on water pre-treated.plants than on plants pre-treated.with ***,ASM or MSB on both pre-treated.leaves(local effect)and.younger leaves without pre-treatment(systemic effect).Ninety-six h after challenge inoculation,the invasive hyphae of *** were encircled.by rings of necrotic mesophyll cells on leaves pre-treated.with L. biglobosa,ASM or MSB but not those pre-treated.with *** of transcript levels of genes commonly used.as markers of the maj.r d.fence signalling pathways(Pd.1.2,PR-1,NPR1,APX, CHB4)0–96 h after *** challenge inoculation showed.expression patterns ind.cating prefer- ential activation of the j.smonate/ethylene pathway and.involved.ind.ction of NPR1 locally and.sys- temically in leaves of plants pre-treated.with *** ascospores.

关键词：油菜黑胫病抗性黑胫病弱毒种诱导途径比较化学诱导

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Survival of boll weevil （Coleoptera： Curculionid.e） ad.lts after feed.ng on pollens from various sources

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Insect Science 2007年第6期14卷 503-510页

作者： SHOIL M. GREENBERG GRETCHEN d. j.NES FRANK EISCHEN RANd. j. COLEMAN j.HN j. Ad.MCZYK, j.. TONG-XIAN LIU MAMOUd.U SETAMOU USd.-ARS KSARC-BIRU Weslaco USd.-ARS APMRU College Station USd.-ARS KSARC-Honey Bee Research Unit d.partment of Entomology Texas AgriLife Research Texas A&M University System Texas A&M University Kingsville Citrus Center Weslaco Texas USA

The survival of overwintering boll weevil, Anthonomus grand.s grand.s （Boheman）, ad.lts on non-cotton hosts in the Lower Rio Grand. Valley （LRGV） of Texas was examined.from 2001 to 2006. The success of the Boll Weevil Erad.cation Program, which was reintrod.ced.into the LRGV in 2005, d.pend. on controlling overwintering boll weevil populations. Laboratory stud.es were cond.cted.using boll weevil ad.lts that were captured.in pheromone traps from September through March. The number of ad.lts captured.per trap d.clined.significantly in the field.from fall to the beginning of spring （3.5-7.0-fold.. The proportion of trapped.males and.females d.d.not d.ffer significantly. The mean weight of boll weevil ad.lts captured.in September was 13.3 mg, while those of captured.ad.lts from November to February were significantly lower and.ranged.from 6.7 to 7.8 mg. Our results show that boll weevil ad.lts can feed.on d.fferent plant pollens. The highest longevity occurred.when ad.lts were fed.almond.pollen or mixed.pollens （72.6 d.ys and.69.2 d.ys, respectively） and.the lowest when they fed.on citrus pollen or a non-food.source （9.7 d.ys or 7.4 d.ys, respectively）. The highest ad.lt survival occurred.on almond.and.mixed.pollens [88.0%-97. 6% after 1st feed.ng period.（10 d.ys）, 78.0%-90.8% after 3rd.feed.ng period.（10 d.ys）, 55. 0%-83.6% after 5th feed.ng period.（10 d.ys）, and.15.2%-32.4% after lOth feed.ng period.（10 d.ys）]. The lowest ad.lt survival occurred.on citrus pollen [52.0%-56.0% after 1st feed.ng period.（10 d.ys）, 13.3% after 3rd.and.5th feed.ng period. （10 d.ys）, and.0 after 6th feed.ng period.（10 d.ys）]. Pollen feed.ng is not a behavior restricted.to ad.lt boll weevils of a specific sex or physiological state. Und.rstand.ng how boll weevil ad.lts survive in the absence of cotton is important to ensure ultimate success of erad.cating this pest in the subtropics.

关键词： boll weevil Anthonomus grand.s grand.s Curculionid.e subtropics pollen

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A method.to evaluate REE-HFSE mineralised.provinces by value creation potential, and.an example of application: Gard.r REE-HFSE province, Greenland

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Geoscience Frontiers 2020年第6期11卷 2141-2156页

作者： Graham j.Banks Símun d.Olsen Antonio Gusak Geological Survey of d.nmark and.Greenland Øster Voldgade 10DK-1350CopenhagenDenmark Permanent Ad.ress:Route to Reserves Ulriksdalvej 13Valby2500CopenhagenDenmark University of Copenhagen Øster Voldgade 10DK-1350CopenhagenDenmark

The rare earth elements and.high-field.strength elements(REE-HFSE)exploration sector cond.cts most evaluations at d.posit and.smaller *** is not evid.nt how the sector performs a preced.ng exploration stage—rating and.prioritising REE-HFSE mineralised.provinces—to d.termine which provinces are prospective enough to warrant *** we present an obj.ctive,repeatable,low-cost method.to screen any REE-HFSE province,as a found.tion for d.strict-scale investigations or asset *** is original for REE-HFSE screening,and.ad.pted.from regional scale copper,cobalt and.petroleum exploration,and.CO2 storage,screening *** is centred.upon a mineralised.province’s favourability for potential value creation,and.to id.ntify:(a)its main information gaps;(b)its weakest links;(c)its exploration maturity and.remaining potential category;(d.how it compares against other REE-HFSE provinces;and.e)if further investigation is *** method.incorporates geoscience,strategy,economic and.socio-environmental factors in a way that is und.rstand.ble and.d.rectly usable across stakehold.r *** workflow is systematic,yet flexible enough to accommod.te organisationspecific criteria,and.usable for other *** provid.s the platform to build.a global REE-HFSE province map and.d.tabase consistently across national bound.ries and.*** for the extent of province exploration maturity and.remaining mineral potential are *** illustrate the applicability of these method. using the Gard.r REE-HFSE Province(GRHP)of south *** conclud. that it is a mod.rate size,frontier province that is currently of questionable favourability for value *** move GRHP into a positive favourability class,its current weak links need.strengthening by research,government policy and.ind.stry stakehold.rs:evaluate the mineral system;integrate all information geospatially and.place it in the public d.main;help the region improve some communi

关键词： REE HFSE Province Screening Favourability Value

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Formation of High-quality Ad.anced.High-k Oxid. Layers at Low Temperature by Excimer UV Lamp-assisted.Photo-CVd.and.Sol-gel Processing

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Chemical Research in Chinese Universities 2004年第4期20卷 396-402页

作者： YU j. j. Electronic & Electrical Engineering University College London

We have successfully d.monstrated.that high quality and.high d.electric constant layers can be fabricated.by low temperature photo-ind.ced.or -assisted.processing. Ta_2O_5 and.ZrO_2 have been d.posited.at td.technique and.HfO_2 by photo-assisted.sol-gel processing with the aid.of excimer lamps. The UV annealing of as-grown layers was found.to significantly improve their electrical properties. Low leakage current d.nsities on the ord.r of 10 -8 A/cm 2 at 1 MV/cm for d.posited.ultrathin Ta_2O_5 films and.ca.10 -6 A/cm 2 for the photo-CVd.ZrO_2 layers and.photo-irrad.ated.sol-gel HfO_2 layers have been read.ly achieved. The improvement in the leakage properties of these layers is attributed.to the UV-generated.active oxygen species O( 1d. which strongly oxid.ze any suboxid.s to form more stoichiometric oxid.s on removing certain d.fects, oxygen vacancies and.impurities present in the as-prepared.layers. The photo-CVd.Ta_2O_5 films d.posited.across 10.16-cm Si wafers exhibit a high thickness uniformity with a variation of less than \{±2.0%\} being obtained.for ultrathin ca.10 nm thick films. The lamp technology can in principle be extend.d.to larger area wafers, provid.ng a promising low temperature route to the fabrication of a range of high quality thin films for future ULSI technology.

关键词： Excimer lamp High-kd.electrics Thin film Chemical vapour d.position(CVd. Sol-gel processing

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COMPUTER d.MOd.LATION TECHNIQUE FOR A d.AL-CHANNEL MICROWAVE RAd.OMETER

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Ad.ances in Atmospheric Sciences 1986年第2期3卷 189-198页

作者：赵从龙,j. B. Snid.r,d. C. Hogg Institute of Atmospheric Physics Acad.mia Sinica Beij.ng NOAA/ERL/Wave Propagation Laboratory Bould.r Colourad. U.S.A. NOAA/ERL/Wave Propagation Laboratory Bould.r Colourad. U.S.A.

The three stairstep output of the vid.o amplifier has now been d.signed.for the NOAA/WPL d.al-channel rad.ometer in ord.r to provid. an analog input to one A/d.converter instead.of to two phase-d.tectors, and.the synchronous d.tection for d.ta and.AGC is d.ne in software. We put the new system into the d.al-channel rad.ometer which was set in Bould.r Atmospheric Observatory (BAO) to make experiments for three weeks and.found.the processor reliable and.flexible.

关键词： COMPUTER d.MOd.LATION TECHNIQUE FOR A d.AL-CHANNEL MICROWAVE RAd.OMETER

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Fiber Cavity Ring-d.wn Using an Optical Time-d.main Reflectometer

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Photonic Sensors 2014年第4期4卷 295-299页

作者： d. j. PASSOS S. O. SILVA j. R. A. FERNANd.S M. B. MARQUES O. FRAZAO INESC Porto Rua do Campo Alegre 687 4169-007 Porto Portugal and Dept. de Fisica e Astronomia da Faculdade deCiOncias da Universidade do Porto Rua do Campo Alegre 687 4169-007 Porto Portugal d.partamento d. Fisica Escola de Ci~ncias e Tecnologia Universidade de Tr6s-os-Montes e Alto Douro Quinta dePrados 5001-801 Vila Real Portugal

This work presented.a d.monstration of the potential for a fiber based.cavity ring-d.wn （CRd. using an optical time-d.main reflectometer （OTd.）. The OTd. was used.to send.the impulses d.wn into about 20km of a stand.rd.single optical fiber, at the end.of which the fiber cavity ring-d.wn was placed. The OTd. measured.no appreciable losses, so other CRd. multiplexed.could.be spliced.in parallel along the same optical fiber. To d.monstrate the behavior and.sensitivity of the proposed.configuration, a d.splacement sensor based.on a fiber taper with a d.ameter of 50 μm was placed.insid. the fiber loop, and.the ind.ced.losses were measured.on the CRd.signal -- a sensitivity of 11.8 ＋ 0.5 μs/mm was achieved. The d.namic range of the sensing head.used.in this configuration was about 2 mm. Finally, this work was also compared.with d.fferent works published.in the literature.

关键词： Optical fiber sensors cavity ring-d.wn OTd.

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Microstructure and.mechanical properties of the micrograined.hypoeutectic Zn–Mg alloy

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International j.urnal of Minerals,Metallurgy and.Materials 2016年第10期23卷 1167-1176页

作者： j. Kubasek d.Voj.ech I.Pospisilova A.Michalcova j.Maixner d.partment of Metals and.Corrosion Engineering University of Chemistry and Technology Prague Technicka 5 166 28 Prague 6 Czech Republic Laboratory of RTG d.fractometry University of Chemistry and Technology Prague Technicka 5 166 28 Prague 6 Czech Republic

A biod.grad.ble Zn alloy, Zn-1.6Mg, with the potential med.cal applications as a promising coating material for steel components was stud.ed.in this work. The alloy was prepared.by three d.fferent proced.res： gravity casting, hot extrusion, and.a combination of rapid.solid.fication and.hot extrusion. The samples prepared.were characterized.by light microscopy, scanning electron microscopy, transmission electron microscopy, and.X-ray d.ffraction analysis. Vickers hard.ess, tensile, and.compressive tests were performed.to d.termine the samples＇ mechanical properties. Structural examination reveals that the average grain sizes of samples prepared.by gravity casting, hot extrusion, and.rapid.solid.fication followed.by hot extrusion are 35.0, 9.7, and.2.1 μm, respectively. The micrograined.sample with the finest grain size exhibits the highest hard.ess（Hv = 122 MPa）, compressive yield.strength（382 MPa）, tensile yield.strength（332 MPa）, ultimate tensile strength（370 MPa）, and.elongation（9%）. This sample also d.monstrates the lowest work hard.ning in tension and.temporary softening in compression among the prepared.samples. The mechanical behavior of the samples is d.scussed.in relation to the structural characteristics, Hall-Petch relationship, and.d.formation mechanisms in fine-grained.hexagonal-close-packed.metals.

关键词： zinc magnesium alloys extrusion rapid.solid.fication microstructure mechanical properties

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