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Seasonal variations of.PM10 -- Trace elements, PAHs and Levoglucosan: Rural sugarcane growing area versus coastal urban area in Southeastern f.orida, USA. Part II: Elemental concentrations

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Particuology 2019年第5期17卷 99-108页

作者： Orhan Sevim oglu Wolf.ang f. Rogge Department of.Environmental Engineering Cebze Technical University Cebze Kocaeli 41400 Turkey School of.Engineering and Sierra Nevada Research Institute University of California Merced. 5200 North Lake Road Merced CA 95343 USA

The largest sugarcane-growing area in the United States is in South f.orida. An estimated 7 million tons of.dry sugarcane leaf. biomass is removed f.om the f.elds bef.re harvest by burning the leaves of. the sugarcane stalks. Preharvest sugarcane leaf.f.liage burning is a major source of.airborne particulate matter (PM), polycyclic aromatic hydrocarbons (PAHs), biogenic trace elements such as K, volatile hydrocarbons and other pollutants. In one harvesting period, approximately 22 million tons of.C02, a greenhouse gas, is released, 7 million tons f.om leaf.f.liage preharvest burning alone and 15 million tons f.om burning sugarcane bagasse in the sugar mills f.r power generation. In this study, PMio was collected f.om Belle Glade, close to the sugarcane-growing area, and f.om Delray Beach, an urbanized area along the East Coast of.f.orida. The PM samples were analyzed f.r trace elements and close to organic compounds. To elucidate the importance of.preharvest sugarcane biomass smoke emissions on air quality, 39 trace elements, 18 PAHs, and levoglucosan were selected to apportion ambient PM constituents. Al, Ca and to a great extend also Mg are the major soil-related trace elements and key markers f.r f.gitive soil dust emissions. Similarly, sea salt aerosol blown f.om the Atlantic Ocean into f.orida added appreciably to PMio trace elements concentration, especially Na and Cl. Approximately half.of.the sea salt aerosol (PMjo -portion) by mass is removed f.om the atmosphere during the transport of.ocean air f.om Delray Beach to Belle Glade. Ambient acid displacement reactions caused a substantial portion of.the Cl (30%) to be liberated f.om the sea salt aerosol to the atmosphere during transport as gaseous HC1. The PAH concentrations at Belle Glade were high when the biomass combustion markers levoglucosan and Incentrations. This indicates that during the sugarcane harvest season, when leaf.f.liage is burned of. just bef.re harvest, most of

关键词： Urban versus rural Trace elements Sugarcane burning Rare earth elements Sea salt aerosol Potassium Levoglucosan PAHs

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Three-dimensional simulation of.long-wavelength f.ee-electron lasers with helical wiggler and ion-channel guiding

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Chinese Physics B 2013年第7期22卷 183-191页

作者： f. Jaf.ri Bahman B. Maraghechi Department of.Physics Amirkabir University of Technology

A three-dimensional simulation of.a steady-state amplif.er model of.a long-wavelength f.ee-electron laser （f.L） with realizable helical wiggler and ion-channel guiding is presented. The set of.coupled nonlinear dif.erential equations f.r electron orbits and f.elds of.TE 11 mode in a cylindrical waveguide are solved numerically by the Runge–Kutta algorithm with averages calculated by the Gaussian quadrature technique. Self.f.elds and space-charge ef.ects are neglected, and the electron beam is assumed to be cold and slippage is ignored. The parameters correspond to the Compton regime. Evolution of.the radiation power and growth rate along the wiggler is studied. Ion-channel density is chosen to obtain optimum ef.iciency. Simulations are pref.rmed f.r the f.L operating in the neighborhood of.35 GHz and 16.5 GHz f.r the electron beam energies of.250 keV and 400 keV, respectively. The result of.the saturated ef.iciency was f.und to be in good agreement with the simple estimation based on the phase-trapping model.

关键词： f.ee-electron laser helical wiggler ion-channel guiding

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Approximate solutions of.Schrdinger equation f.r Eckart potential with centrif.gal term

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Chinese Physics B 2010年第9期19卷 155-160页

作者： f. Taskin G. Koak Department of.Physics Erciyes University

The approximate analytical solutions of.the Schrodinger equation f.r the Eckart potential are presented f.r the arbitrary angular momentum by using a new approximation of.the centrif.gal term. The energy eigenvalues and the corresponding wavef.nctions are obtained f.r dif.erent values of.screening parameter. The numerical examples are presented and the results are in good agreement with the values in the literature. Three special cases, i.e., s-wave, ξ= λ=1, and β=0, are investigated.

关键词： Schrodinger equation Eckart potential bound state

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A Model f.r Liquid-Dif.usion Catalytically Grown f.brous Carbon Material

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Journal of.Materials Science & Technology 1999年第1期15卷 1-4页

作者： Zhang, WG Cheng, HM Su, G f.n, YY Li, f.Shen, ZH Zhou, bl Chinese Acad Sci Met Res Inst Shenyang 110015 Peoples R China

A mechanism f.r the catalytically growth of.vapor grown f.brous carbon (VGf.) preparing f.om the f.oating catalyst method has been proposed, in which liquid dif.usion-determined dif.usion of.carbon atoms through catalyst particles is described mathematically, and the physical and chemical properties of.the catalyst particles during the growth process are taken into account. f.om the model the growth rate and grown length of.VGf. are calculated theoretically which coincides with the experimental data; and the necessity of.reducing gas such as hydrogen in preparing VGf. is explained as to reduce f.3C, which acts as intermediate catalyst shown by the model. f.3C f.rmed on the surf.ce of.gamma-f. will stop the growth of.carbon f.ber if.they can not be reduced at once. Additionally, the growth temperature and diameter of.VGf. are also discussed in the paper.

关键词： Li Cs A Model f.r Liquid-Dif.usion Catalytically Grown f.brous Carbon Material

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Stable non-synonymous substitutions on NS gene (NS1 and NS2 proteins) of.Qinghai lake H5N1 inf.uenza virus (Clade 2.2) af.er successive passages in Muscovy ducks

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Science China(Lif. Sciences) 2009年第9期52卷 847-853页

作者： GAO George f. Key Laboratory of.Pathogenic Microbiology and Immunology of.CAS (CASPMI) Institute of Microbiology Chinese Academy of Sciences (CAS) China-Japan Joint Laboratory of.Molecular Immunology and Molecular Microbiology Institute of Microbiology Chinese Academy of Sciences Graduate University of.Chinese Academy of.Sciences Beijing Institutes of.Lif. Science Chinese Academy of Sciences

Although worldwide concern has been raised since the large-scale outbreak of.highly pathogenic avian inf.uenza in wild birds at Qinghai Lake,China in 2005,the f.ctors responsible f.r the ability to kill waterf.wl remain unclear. The why and how questions of.the H5N1 virus species-jump into its reservoir host need to be answered. In this report we test the pathogenicity and adaptation of.Qinghai Lake (Clade 2.2) isolate to Muscovy ducks f.r f.rther understanding of.this virus. The isolate was highly pathogenic in ducks and retained its high pathogenicity even af.er 20 generations of.passage in ducks. During the process of.serial passages,only the NS gene developed non-synonymous substitutions,which caused two mutations in NS1 protein (Val23Ala and Leu207Pro) and one in NS2 (Phe55Leu). These mutations persisted immutably through all subsequent passages and the pathogenicity remained high,implying that highly pathogenic H5N1 virus remains stable in aquatic birds through oral transmission. Although the exact f.nctions of.these mutations are not known,our results provide an important f.undation f.r f.rther understanding the characteristics of.the Qinghai Lake isolates.

关键词： avian inf.uenza virus H5N1 mutation NS1/2 serial passages

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Predicting global landslide spatiotemporal distribution:Integrating landslide susceptibility zoning techniques and real-time satellite rainf.ll estimates

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International Journal of.Sediment Research 2008年第3期23卷 249-257页

作者： Robert f. ADLER Senior Research Scientist Code 613.1 Laboratory for Atmospheres NASA/Goddard Space Flight Center Greenbelt MD 20771 U. S. ADr.

Landslides triggered by rainf.ll can possibly be f.reseen in real time by jointly using rainf.ll intensity-duration thresholds and inf.rmation related to land surf.ce susceptibility. However, no system exists at either a national or a global scale to monitor or detect rainf.ll conditions that may trigger landslides due to the lack of.suf.icient ground-based observing network in many parts of.the world. Recent advances in satellite remote sensing technology and increasing availability of.high-resolution geospatial products around the globe have provided an unprecedented opportunity f.r such a study. In this paper, a f.amework f.r developing a preliminary real-time prediction system to identif. where rainf.ll-triggered landslides will occur is proposed by combining two necessary components: surf.ce landslide susceptibility and a real-time space-based rainf.ll analysis system (http://***). f.rst, a global landslide susceptibility map is derived f.om a combination of.semi-static global surf.ce characteristics (digital elevation topography, slope, soil types, soil texture, land cover classif.cation, etc.) using a GIS weighted linear combination approach. Second, an adjusted empirical relationship between rainf.ll intensity-duration and landslide occurrence is used to assess landslide hazards at areas with high susceptibility. A major outcome of.this work is the availability f.r the f.rst time of.a global assessment of.landslide hazards, which is only possible because of.the utilization of.global satellite remote sensing products. This preliminary system can be updated continuously using the new satellite remote sensing products. This proposed system, if.pursued through wide interdisciplinary ef.orts as recommended herein, bears the promise to grow many local landslide hazard analyses into a global decision-making support system f.r landslide disaster preparedness and mitigation activities across the world.

关键词： Landslide Natural disasters Satellite remote sensing Real-time precipitation analysis Landslide susceptibility

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Evaluation of.Metal f.tigue Problems Using Qualitative Reasoning Approach

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Tsinghua Science and Technology 2008年第S1期13卷 96-101页

作者： Siegf.ied f. Stiemer Civil Engineering Department University of British Columbia

f.tigue f.ilures are of.en encountered in steel structures under heavy cyclic loadings. This paper presents metal f.tigue problems in structural engineering using outcomes of.recent advancements in numerical qualitative reasoning. Qualitative reasoning provides an ef.ective and sound technique f.r solving complex and uncertain scenarios, regardless of.the uncertainty or linearity of.the design parameters and their constraints. This paper introduces the algorithms behind a sof.ware platf.rm, built upon numerical qualitative reasoning f.r engineering applications. The sof.ware expresses the results of.the analysis in variable ranges and diagrams showing a two-dimensional design space. The capability of.representing design parameters and outcomes in solution spaces provides a practical way f.r engineers to leverage their existing knowledge and experience. Case studies in metal f.tigue design are given to ref.ect on the capability of.qualitative reasoning in engineering applications.

关键词： computer applications conceptual design decision support system constraints qualitative reasoning f.tigue

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A case f.r mantle plumes

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Chinese Science Bulletin 2005年第15期50卷 1541-1554页

作者： Geof.rey f. Davies Research School of.Earth Sciences Australian National University Canberra ACT 0200 Australia

The existence of.at least several plumes in the Earth’s mantle can be inf.rred with f.w assumptions f.om well-established observations. As well, thermal mantle plumes can be predicted f.om well-established and quanti-f.ed f.uid dynamics and a plausible assumption about the Earth’s early thermal state. Some additional important ob-servations, especially of.f.ood basalts and rif.-related mag-matism, have been shown to be plausibly consistent with the physical theory. Recent claims to have detected plumes using seismic tomography may comprise the most direct evidence f.r plumes, but plume tails are likely to be dif.icult to resolve def.nitively and the claims need to be well tested. Although signif.cant questions remain about its viability, the plume hypothesis thus seems to be well worth continued investiga-tion. Nevertheless there are many non-plate-related mag-matic phenomena whose association with plumes is unclear or unlikely. Compositional buoyancy has recently been shown potentially to substantially complicate the dynamics of.plumes, and this may lead to explanations f.r a wider range of.phenomena, including “headless” hotspot tracks, than purely thermal plumes.

关键词：地球覆盖物羽毛流体动力学热量对流火山

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Variation in growth potential between hybrid clones of.Eucalyptus trees in eastern South Af.ica

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Journal of.f.restry Research 2017年第6期28卷 1154-1164页

作者： Sileshi f. Melesse Temesgen Zewotir School of.Mathematics Statistics and Computer ScienceUniversity of KwaZulu-Natal Pietermaritzburg South Africa

Growth of.commercial f.restry is highly dependent on the availability of.f.st-growing planting materials. Consequently, the ef.icient utilization of.f.stgrowing plantations can greatly impact productivity. The objectives of.this study were to evaluate variations in the growth potential of.two clones and to estimate the average stem radial growth advantage of.a f.st-growing clone using data obtained f.om Sappi landholdings in eastern South Af.ica and a mixed modelling approach that permits the incorporation of.covariance structure into the statistical model. During the f.rst 2 years of.growth, the stem radius of.nine trees each of.two clones was measured using dendrometer attached to the tree. A second-degree f.actional polynomial model was chosen to show the f.nctional relationship between stem radius and tree age. Growth of.the two hybrid clones dif.ered signif.cantly. The Eucalyptus grandis×Eucalyptus urophylla clone grew f.ster than the E. grandis×camaldulensis clone, indicating better genetic potential f.r rapid growth and yield. This study can be considered as starting point to f.rther compare the potential f.r rapid growth of.several hybrid clones using the longitudinal data modelling approach.

关键词： Covariance f.nction Dendrometer trial Growth rate Loess Longitudinal study Random slope

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Soil Properties in Conif.rous f.rest Stands Along a f.y Ash Deposition Gradient in Eastern Germany

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Pedosphere 2005年第6期15卷 681-694页

作者： S. KLOSE f. MAKESCHIN Institute of.Soil Science Faculty of Forest Geo and Hydro Sciences Dresden University of Technology P.O. 1117 D-01735 Tharandt (Germany)

Physical, chemical, and microbial properties of.f.rest soils subjected to long-term f.y ash depositions were analyzed in spruce (Picea abies (L.) Karst.) stands of.eastern Germany on three f.rest sites along an emission gradient of.3 (high input), 6, and 15 km (low input) downwind of.a coal-f.red power plant. Past emissions resulted in an atypical high mass of.mineral f.y ash constituents in the organic horizons at the high input site of.128 t ha-1 compared to 58 t ha-1 at the low input site. Magnetic susceptibility measurements proved that the high mineral content of.the f.rest f.oor was a result of.f.y ash accumulation in these f.rest stands. f.y ash deposition in the organic horizons at Site I versus III signif.cantly increased the pH values, ef.ective cation exchange capacity, base saturation and, with exception of.the L horizon, concentrations of.mobile heavy metals Cd, Cr, and Ni, while stocks of.organic C generally decreased. A principal component analysis showed that organic C content and base status mainly controlled soil microbial biomass and microbial respiration rates at these sites, while pH and mobile f.actions of.Cd, Cr, and Ni governed enzyme activities. Additionally, it was hypothesized that long-term f.y ash emissions would eventually destabilize f.rest ecosystems. Theref.re, the results of.this study could become a usef.l tool f.r risk assessment in f.rest ecosystems that were subjected to past emissions f.om coal-f.red power plants.

关键词： conif.rous f.rests f.y ash deposition magnetic susceptibility microbial biomass mobile heavy metal f.action

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