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Near earth Vortices Driving of Field Aligned Currents Based on Magnetosphere Multiscale and Swarm Observations

空间科学学报 2019年第1期39卷 9-17页

作者： ZHANG C SHeN C y.NG y.y.DUNLOP M W TI S RUSSeLL C T LüHR H BURCH j L LINDQVIST P A TORBeRT R B FRIIS-CHRISTeNSeN e State Key.Laboratory.of Space Weather National Space Science Center College of earth Science University of Chinese Academy of Sciences College of Science Harbin Institute of Technology Institute of China Seismological Bureau Crustal Stress Space Science Institute School of Astronautics Beihang University Rutherford Appleton Laboratory University.of California German Research Center For Geosciences German Research Center for Geosciences Southwest Research Institute Roy.l Institute of Technology University.of New Hampshire Danish National Space Center

A long-standing my.tery.in the study.of Field-Aligned Currents(FACs) has been that: how the currents are generated and why.they.appear to be much stronger at high altitudes than in the ionosphere. Here we present two events of magnetotail FACs observed by.the Magnetospheric Multiscale Spacecraft(MMS) on 1 st july.and 14 th july.2016, to show how the Substorm Current Wedges(SCW) were formed. The results show that particles were transferred heading towards the earth during the expansion phase of *** azimuthal flow formed clockwise(counter-clockwise) vortex-like motion, and then generated downward(upward) FACs on the tailward/poleward side of the distorted field with opposite vorticity.on their earthward/equatorward side. We also analy.ed the Region 1 FACs observed by.the earth explorer Swarm spacecraft on 1 st july.2016 and found that they.were associated with FACs observed by.MMS, although differing by.a factor of 10. This difference suggests that either there was the closure of the currents at altitudes above 500 km or the currents were not strictly.parallel to B and closed at longitudes away.from where they.were generated.

关键词： Substorm current wedge Magnetosphere Field-aligned currents Flow vorticity Multiple spacecraft measurements

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Modeling biomembranes and red blood cells by.coarse-grained particle methods

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Applied Mathematics and Mechanics(english edition) 2018年第1期39卷 3-20页

作者： H.LI H.y.CHANG j.y.NG L.LU y.H.TANG G.Ly.OTRAFITIS Division of Applied Mathematics Brown University Department of Materials Science and engineering Massachusetts Institute of Technology Department of Mechanical engineering University of Connecticut

In this work, the previously.developed coarse-grained （CG） particle models for biomembranes and red blood cells （RBCs） are reviewed, and the advantages of the CG particle methods over the continuum and atomistic simulations for modeling biological phenomena are discussed. CG particle models can largely.increase the length scale and time scale of atomistic simulations by.eliminating the fast degrees of freedom while preserving the mesoscopic structures and properties of the simulated sy.tem. Moreover, CG particle models can be used to capture the microstructural alternations in diseased RBCs and simulate the topological changes of biomembranes and RBCs, which are the major challenges to the ty.ical continuum representations of membranes and RBCs. The power and versatility.of CG particle methods are demonstrated：through simulating the dy.amical processes mvolving significant topological .changes e.g. lipid self-assembly.vesicle fusion and membrane budding.

关键词： coarse-grained molecular dy.amics,lipid bilay.r red blood cell membrane membrane fusion

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evaluation of Accuracy.and Precision of IRMS by.Using Standard Materials and Applications

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journal of Agricultural Chemistry.and environment 2016年第4期5卷 211-222页

作者： j. y. hwang B. K. Kim M. S. Kim j. W. Choi T. S. Kim W. S. Lee Soil and Groundwater Research Division National Institute of Environmental Research Environment Research Complex Incheon Republic of Korea environmental Measurement & Analy.is Center National Institute of Environmental Research Environment Research Complex Incheon Republic of Korea Integrated Pollution Prevention and Control Task Force National Institute of Environmental Research Environment Research Complex Incheon Republic of Korea

The isotope ratio mass spectrometer (IRMS) is an instrument that measures both of the elemental contents and isotope ratios of hy.rogen, oxy.en, carbon, nitrogen and sulfur in environmental samples at the same time. In this study. we want to try.to get two main goals;first, to make up for setting the analy.ical conditions such as accuracy.and precision, second, to apply.for comparing of the carbon and nitrogen isotope ratio of sediments in the abandoned mine located in middle province of Korea. For the first goal, a recently.introduced IRMS was used to analy.e CRM (certified reference materials), which helped to make up the analy.ical conditions of carbon and nitrogen isotope ratios. So, the accuracy.and precision of isotope ratios and elemental contents were also assessed simultaneously. and also the results were very.satisfactory. The analy.ical results of carbon reference materials (eMA-P2) showed an accuracy.of -2.801 × 10‰ ± 0.01‰ (2σ) and a precision of 0.009‰ in the mass range from 0.008 μg - 0.162 μg. For nitrogen reference materials (eMA-P2), an accuracy.of -1.632‰ ± 0.72‰ (2σ) was obtained in the mass range from 0.082 - 0.162 mg. These values of accuracy.and precision are higher than those reported by.other studies. For the second goal, carbon and nitrogen isotopes in river sediment near abandoned mines were analy.ed based on the established analy.ical conditions. The result suggested that carbon isotope ratios ranged from -22.5‰ - -7.5‰ and nitrogen isotope ratios from -1.9‰ - 7.9‰. By.comparing the isotope ratios and sampling sites of sediment, we know that the nitrogen isotope values in samples of entrance area of mine are greater than those of the farm house area, which is indicating the effects of organic materials. So, we could guess that the newly.accumulated organic materials were much more in the farm house area than mine entrance area. And a result of this study. the accuracy.and precision tests of IRMS using certified reference materials were ve

关键词： Stable Isotope Carbon Isotope Nitrogen Isotope Precision Accuracy

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Searching for Bacterial Biofilm in Recurrent Cholangitis in Primary.Sclerosing Cholangitis:A Case Presentation and Introduction of an Unexplored Disease Mechanism

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journal of Clinical and Translational Hepatology 2018年第1期6卷 114-118页

作者： Aly.sa y. Choi Florencia jalikis Maria Westerhoff Sarag Boukhar elinor Pulcini Chris Damman Lei y. Department of Internal Medicine University of WashingtonSeattleWashingtonUSA Department of Pathology University of WashingtonSeattleWashingtonUSA Department of Pathology University of IowaIowa CityIowaUSA Center for Biofilm engineering Montana State UniversityBozemanMontanaUSA Division of Gastroenterology University of WashingtonSeattleWashingtonUSA

Inflammation and fibrosis of the bile ducts are the defining pathological characteristics of primary.sclerosing cholangitis(PSC).A previously.unexplored mechanism for recurrent cholangitis,one of PSC's most common presentations,is bacterial colonization of the biliary.epithelium in the form of biofilm,which may.confer resistance to antibiotics and host phagocy.ic *** aim of the current study.was to assess whether bacteria could be seen on the liver explant and whether they.organized in the form of *** explanted PSC liver from a 60-y.ar-old male who suffered from recurrent cholangitis was formalin-fixed,paraffinembedded and Gram *** specimens were observed under light *** bacteria nor biofilm were *** did not detect bacteria or biofilm in the liver explant of a single PSC patient with recurrent cholangitis using standard light *** suspect this may.be in part due to techniques related to tissue preservation and microscopy.

关键词： Primary.sclerosing cholangitis Recurrent cholangitis Biofilm

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Producing Renewable Biodiesel Fuel Using the Transesterification Process

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World journal of engineering and Technology 2015年第3期3卷 105-110页

作者： T. W. Chung y. j. Chen Department of Chemical engineering Chung Yuan Christian University Taoyuan Taiwan

Biodiesel fuels are considered an alternative to fossil fuels. This is one of the effective means of transferring solar energy.to dy.amic energy.via photosy.thesis. It is also being considered in order to reduce the levels of carbon dioxide production worldwide. Biodiesel fuels are a renewable, biodegradable, and clean energy.source. Producing enough biofuels to replace fossil fuels will bring the advantages of reduced air pollution and reduced other environmental impacts of fossil fuels. In this study. the response surface methodology.(RSM) was used to design the experimental runs and to discuss the manufacturing variables on the transesterification of palm oil into fatty.acid methy. ester (i.e. biodiesel fuel). The variation of the degree of effect for each variable in the transesterification process was observed. A second-order model was obtained to predict the y.eld of biodiesel fuel and the viscosity.as a function of the reaction time, the mass fraction of cataly.t in methanol and the molar ratio of methanol to plant oil. The experimental data of the y.eld and the viscosity.of biodiesel fuels in different manufacturing variables are discussed in this study. Analy.is of variance (ANOVA) was also applied to discuss the main factor and interaction factor effects of the manufacturing variables on the responses of the y.eld of unrefined biodiesel fuels. The shortage of farmland in Taiwan is a problem that needs to be solved before mass propagation of biofuels can be accomplished. In southeastern Asia, there are many.farms and most energy.farm products are cultivated (e.g. palm oil or jatropha oil). In addition to sunflowers and soy.eans in Taiwan, those energy.farm products are possible choices for production of biodiesel fuel in Taiwan. The cooperation between Indonesia and Taiwan on the plantation of palm or jatropha trees in Indonesia has conducted and will be one of the possible way. to solve the problem of the shortage of energy.farm products in Taiwan.

关键词： Renewable Biodiesel Palm Oil Transesterification Response Surface Methodology (RSM)

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Diagrammatic Iteration Approach to electron Correlation effects

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journal of Modern Phy.ics 2014年第7期5卷 549-561页

作者： j. D. Fan y. M. Malozovsky Chongqing Center for Superconductive Science & Technology Chongqing Academy of Science and Technology Chongqing China jD Duz Institute for Superconductivity Baton Rouge USA

electron correlation is a measure of the errors that are inherent in the Hartree-Fock theory.or orbital models. When the electron density.is high, correlation is weak and the traditional electronic theory.works well. However, at a low density.of electrons correlation effects become strong and the traditional theory.fails to describe the electron sy.tem correctly. Therefore, the electron correlation play. a radical role in such materials as high-temperature superconductors and heavy.fermions, etc. To date, there is no agreement on how to deal with higher-order terms (correlation energy. in the series of electron’s ground state energy.although a method that is termed diagrammatic iteration approach (DIA) was developed more than one decade ago by.the authors of this article. That is why.no consensus on the origin and mechanism of superconductivity.has been engaged in superconductivity.community. From the viewpoint of methodology. the DIA is indeed an approach to higher-order terms from the lower-order ones, i.e. it is a new method to show how to go bey.nd the random phase approximation (RPA) step by.step by.iteration. Here, we are logically.presenting it to the community.of modern phy.ics with more analy.es and hope to attract more attention to it and promote its applications.

关键词： electron Correlation effect Diagrammatic Iteration Approach Superconductivity Condensed Matter Phy.ics

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Molecular Dy.amics Simulation of Porous Lay.r-enhanced Dislocation emission and Crack Propagation in Iron Cry.tal

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journal of Materials Science & Technology 2011年第11期27卷 1025-1028页

作者： D. Li F.y. Meng X.Q. Ma L.j. Qiao W.y. Chu Department of Phy.ics University of Science and Technology Beijing Beijing 100083 China Corrosion and Protection Center Key Lab of Environmental Fracture （Ministry of Education） University of Science and Technology Beijing Beijing 100083 China

The internal stress induced by.a porous lay.r or passive lay.r can assist the applied stress to promote dislocation emission and crack propagation, e.9. when the pipeline steel is buried in the soil containing water, resulting in stress corrosion cracking （SCC）. Molecular dy.amics （MD） simulation is performed to study.the process of dislocation emission and crack propagation in a slab of Fe cry.tal with and without a porous lay.r on the surface of the crack. The results show that when there is a porous lay.r on the surface of the crack, the tensile stress induced by.the porous lay.r can superimpose on the external applied stress and then assist the applied stress to initiate crack tip dislocation emission under lowered stress intensity.KI, or stress. To respond to the corrosion accelerated dislocation emission and motion, the crack begins to propagate under lowered stress intensity.KI, resulting in SCC.

关键词： Molecular dy.amics simulation Dislocation emission Crack propagation Porouslay.r Stress intensity

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The Sy.thesis and Structure of Adduct of a New Schiff Base Macrocy.le with Two THF: THIONe_2B_4[36]eNe-O_6N_8·2THF

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Chinese Chemical Letters 1996年第10期7卷 884-885页

作者： Lin Z.G. Chen H.y. Lin y.j. Huang F.H. Department of Chemistry Fujian Teachers' University Fuzhou 350007 State Key.Lab. of Struct. Chemistry Fujian Inst. Res. Struct. of Matter Fuzhou 350002

New Schiff base Macrocy.lic compound of 2,3: 11, 12:20, 21:29, 30-tetrabenzo-1,13,16,19,31,34-hexaoxa-5,6,8,9,23,24,26,27-octaaza-7,25-dithione-2,3:4,5:9,10:11,12:22, 23:27,28:29,30 cy.lo-[36]ene (thione2B4[36] ene-O6N8) containing THF has been prepared. It cry.tallizes in the monoclinic, space group P21/n. with parameters a=9.829(5) b=24.23(1), c=10.181(9), β=92.93(5)°, Z=2, V=2422(3)3, Dc=1.25gcm-3. Data collection: Rigaku AFC-5R diffractometer,(MoKα, λ=0.71069), ω /2θ scans. θmax=25°, empirical absorption correction, 4658 measured reflections, 4387 independent, 1743 observed reflections [I≥3σ(I)]. The final R=0.056. RW=0.069,S=1 .54, (Δ/σ)max=0.01,Δρmax=0.36e-3.

关键词： eNe and Macrocy.le New O6N8 Schiff Structure Sy.thesis THIONe2B4 The Adduct THF

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A new cache of eoarchaean detrital zircons from the Singhbhum craton,eastern India and constraints on early.earth geody.amics

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Geoscience Frontiers 2019年第4期10卷 1359-1370页

作者： Bulusu Sreenivas Sukanta Dey.y.j. Bhaskar Rao T. Vijay. Kumar e.V.S.S.K. Babu Ian S. Williams CSIR-National Geophy.ical Research Institute Hyderabad 500007India Department of earth Sciences Indian Institute of Science Education and ResearchKolkata 741246India Research School of earth Sciences The Australian National UniversityCanberra 2601Australia

The dominant geody.amic processes that underpin the formation and evolution of earth’s early.crust remain enigmatic calling for new information from less studied ancient cratonic ***,we present U-Pb ages and Hf isotopic compositions of detrital zircon grains from^2.9 Ga old quartzites and magmatic zircon from a 3.505 Ga old dacite from the Iron Ore Group of the Singhbhum craton,eastern *** detrital zircon grains range in age between 3.95 Ga and 2.91 *** with the recently.reported Hadean,eoarchean xenocry.tic(up to 4.24 Ga)and modem detritus zircon grains from the Singhbhum craton,our results suggest that the eoarchean detrital zircons represent crust generated by.recy.ling of Hadean felsic crust formed at^4.3-4.2 Ga and^3.95 *** observe a prominent shift in Hf isotope compositions at^3.6-3.5 Ga towards super-chondritic values,which signify.an increased role for depleted mantle and the relevance of plate *** Paleo-,Mesoarchean zircon Hf isotopic record in the craton indicates crust generation involving the role of both depleted and enriched mantle *** infer a short-lived suprasubduction setting around^3.6-3.5 Ga followed by.mantle plume activity.during the Paleo-,Mesoarchean crust formation in the Singhbhum *** Singhbhum craton provides an additional repository.for earth’s oldest materials.

关键词： U-Pb zircon ages Hf isotopes Singhbhum craton Hadean eoarchean Geody.amics

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Distribution of snow depth variability

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Frontiers of earth Science 2018年第4期12卷 683-692页

作者： S.R.FASSNACHT K.S.j.BROWN e.j.BLUMBeRG j.I.LOPeZ MOReNO T.P.COVINO M.KAPPAS y.HUANG V.LeONe A.H.KASHIPAZHA eSS-Watershed Science Colorado State UniversityFort CollinsCO 80523-1476USA Cooperative Institute for Research in the Atmosphere Fort CollinsCO 80523-1375USA Natural Resources ecology.Laboratory Fort CollinsCO 80523-1499USA Geographisches Institut Georg-August-Universitat Gottingen37077GottingenDeutschland Geosciences Colorado State UniversityFort CollinsCO 80523-1482USA Instituto Pirenaico de ecologia CSICCampus de Aula Dei50080ZaragozaEspana State Key.Laboratory.of Fly.roscience and engineering Tsinghua UniversityBeijing 100084China Seconda Universita degli Studi di Napoli Viale Abramo Lincoln581100Caserta CEItalia

Snow depth is the easiest snowpack property.to measure in the field and is used to estimate the distribution of snow for quantify.ng snow storage. Often the mean of three snow depth measurements is used to represent snow depth at a location. This location is used as a proxy.for an area, ty.ically.a digital elevation model (DeM) or remotely.sensed pixel. Here, 11, 17, or 21 snow depth measurements were used to represent the mean snow depth of a 30-m DeM pixel. Using the center snow depth measurement for each sampling set was not adequate to represent the pixel mean, and while the use of three snow depth measurements improved the estimate of mean, there is still large error for some pixels. These measurements were then used to determine the variability.of snow depth across a pixel. estimating variability.from few points rather than all in a measurement was not sufficient. The sampling size was increased from one to the total per pixel (11, 17, or 21) to determine how many.point samples were necessary.to approximate the mean snow depth per pixel within five percent. Binary.regression trees were constructed to determine which terrain and canopy.variables dictated the spatial distribution of the snow depth, the standard deviation of snow depth, and the sample size to within 5% of the mean per pixel. One location was measured in two y.ars just prior to peak accumulation, and it is shown that there was little to no inter-annual consistency.in the mean or standard deviation.

关键词： uncertainty sampling binary.regression trees snow telemetry

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