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The role of decomposition reactions in assessing first-principles predictions of solid stability

npj Computational materials 2019年第1期5卷 1120-1128页

作者： Christopher J.Bartel Alan W.Weimer Stephan Lany charles B.musgrave Aaron m.Holder Department of Chemical and Biological Engineering University of ColoradoBoulderCO 80309USA National Renewable Energy Laboratory GoldenCO 80401USA Department of Chemistry University of ColoradoBoulderCO 80309USA

The performance of density functional theory approximations for predicting materials thermodynamics is typically assessed by comparing calculated and experimentally determined enthalpies of formation from elemental phases,ΔH_(f).However,a compound competes thermodynamically with both other compounds and their constituent elemental forms,and thus,the enthalpies of the decomposition reactions to these competing phases,ΔH_(d),determine thermodynamic *** evaluated the phase diagrams for 56,791 compounds to classify decomposition reactions into three types:*** that produce elemental phases,*** that produce compounds,and *** that produce *** analysis shows that the decomposition into elemental forms is rarely the competing reaction that determines compound stability and that approximately two-thirds of decomposition reactions involve no elemental *** experimentally reported formation enthalpies for 1012 solid compounds,we assess the accuracy of the generalized gradient approximation(GGA)(PBE)and meta-GGA(SCAN)density functionals for predicting compound *** 646 decomposition reactions that are not trivially the formation reaction,PBE(mean absolute difference between theory and experiment(mAD)=70 meV/atom)and SCAN(mAD=59 meV/atom)perform similarly,and commonly employed correction schemes using fitted elemental reference energies make only a negligible improvement(~2 meV/atom).Furthermore,for 231 reactions involving only compounds(Type 2),the agreement between SCAN,PBE,and experiment is within~35 meV/atom and is thus comparable to the magnitude of experimental uncertainty.

关键词： stability stability solid

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mapping of groundwater potential zones in the drought-prone areas of south madagascar using geospatial techniques

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Geoscience Frontiers 2020年第4期11卷 1403-1413页

作者： charles Serele Ana Perez-Hoyos Francois Kayitakire UNICEF Madagascar European Commission Joint Research Centre(JRC)Via E.Fermi 2749I-21027IspraVAItaly

The southern regions of madagascar have the country’s lowest water supply coverage and are highly vulnerable to *** to potable drinking water is a major challenge for the local *** droughts lead to annual emergency appeals to save the lives of acute malnourished ***’s response consisting in providing potable drinking water through the drilling of boreholes has been challenged by the complex hydrogeology,the low yield of boreholes and high-level salinity of water,the lack of reliable groundwater data and the weak capacity of the drilling *** constraints result in a high rate of drilling *** improve drilling success and provide more potable drinking water to local communities,it is vital to undertake reliable groundwater *** madagascar and the European Union delegation in madagascar collaborated on the use of satellite imagery to improve sector knowledge and access to safe and clean water for local communities in southern *** methodology relies on produce thematic layers of groundwater potential ***,these thematic layers were overlaid with ground-based hydrogeological data to map the groundwater potential zones(GWP) and identify the most suitable sites for borehole siting and *** of this study are very encouraging,and the integrated approach used has proven its applicability in mapping groundwater potential areas in the eight drought-affected areas of south *** groundwater potential zone map is being used by UNICEF and partners to plan water supply projects and identify the best sites for positioning new boreholes and reduce the likelihood of drilling ***,the project developed a database of groundwater resources,which will improve knowledge of the regional hydrogeological context and strengthen the capacity of the water *** learnt from this study show that an integration of the groundwater potential zone map with demographics a

关键词： Groundwater potential zones(GWP) Overlay analysis Remote sensing Geographic information system(GIS) South madagascar

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measurement of Anomalous Radon Gas Emanation Across the Yammouneh Fault in Southern Lebanon: A Possible Approach to Earthquake Prediction

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International Journal of Disaster Risk Science 2015年第3期6卷 250-266页

作者： mohammed A.Kobeissi Francisco Gomez charles Tabet Lebanese Atomic Energy Commission Lebanese National Council for Scientific Research Department of Geological Sciences University of Missouri Lebanese National Council for Scientific Research BeirutLebanon

The eastern mediterranean region is an active tectonic setting that includes the Dead Sea Transform Fault, which forms the boundary between the African and the Arabian Plates and crosses Lebanon from south to north, striking in a restraining bend around 25–30°NE. The major structural feature in Lebanon is the Yammouneh Fault, which reaches to Syria and southern Turkey in a north–south direction. measurements of radon gas concentration and exhalation rates in two locations along the southern segment of the Yammouneh Fault in south Lebanon were performed. Two profiles in the El-Khiam basin and Blat pull-apart basin and perpendicular to the Yammouneh Fault trace were analyzed. An approximate fault width 25–30 m wide was determined in the El-Khiam study area. Temporal increase of radon concentration was measured and correlated with stress/strain tectonic activity and stress drops along the studied fault segment *** variable radon concentrations were detected during one of the measurements where an earthquake occurred in the region of Tiberias Lake in northern Palestine along the Yammouneh Fault in the study area. measurements of radon concentration along a station’s profile in Blat village did not show any radon anomalous variation due to the discontinuity along the fault(pull-apart), and possible absence of stress and energy accumulation along the Yammouneh Fault line in that location.

关键词： CR-39 Detector Earthquake prediction Exhalation rate Lebanon Radon Stress/strain

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Comparing carbon accumulation in restored and natural wetland soils of coastal Louisiana

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International Journal of Sediment Research 2019年第6期34卷 600-607页

作者： Glenn m.Suir charles E.Sasser Ronald D.DeLaune Elizabeth O.murray U.S.Army Engineer Research and Development Center Environmental LaboratoryWetlands and Environmental Technologies Research Facility Louisiana State University Department of Oceanography and Coastal ScienceCollege of the Coast and Environment U.S.Army Engineer Research and Development Center Environmental Laboratory

Louisiana’s chronic wetland deterioration has resulted in massive soil organic matter loss and subsequent carbon release through *** combat these losses,and reestablish ecosystem function,goods,and services,many restoration projects have been constructed or planned throughout coastal *** are significant data gaps and conflicting results regarding wetland contributions to global warming,especially related to carbon sequestration in restored *** exceptionally large data set was used to derive carbon accumulation rates from key soil characteristics and *** and comparisons of bulk density,organic matter,total carbon,vertical accretion(short-and longer-term),and carbon accumulation rates were made across time(chronosequence) and space(i.e.,coastwide,watershed basins,and vegetation zones).Carbon accumulation rates in the Louisiana coastal zone were generally correlated to hydrogeomorphology,with higher rates occurring in zones of high river connectivity or in swamp or higher salinity tolerant *** average,naturally occurring wetlands had higher carbon accumulation rates than restoration *** some restoration measures were higher,and most showed increasing carbon accumulation rates over *** demonstrate that although wetland restoration provides many ecosystem benefits,the associated carbon sequestration may also provide useful measures for climate change management.

关键词： Wetland productivity Chronosequence Carbon sequestration Wetland restoration Coastal Louisiana

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A Phase-Field model Coupled with Lattice Kinetics Solver for modeling Crystal Growth in Furnaces

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Communications in Computational Physics 2014年第1期15卷 76-92页

作者： Guang Lin Jie Bao Zhijie Xu Alexandre m.Tartakovsky charles H.Henager Jr. Computational mathematics Group Pacific Northwest National LaboratoryRichlandWA 99352 USA. Fluid and Computational Engineering Group Northwest National LaboratoryRichlandWA 99352 USA. Engineering mechanics and Structure materials Group Northwest National LaboratoryRichlandWA 99352 USA.

In this study,we present a new numerical model for crystal growth in a vertical solidification *** model takes into account the buoyancy induced convective flow and its effect on the crystal growth *** evolution of the crystal growth interface is simulated using the phase-field method.A semi-implicit lattice kinetics solver based on the Boltzmann equation is employed to model the unsteady incompressible *** model is used to investigate the effect of furnace operational conditions on crystal growth interface profiles and growth *** a simple case of macroscopic radial growth,the phase-field model is validated against an analytical *** numerical simulations reveal that for a certain set of temperature boundary conditions,the heat transport in the melt near the phase interface is diffusion dominant and advection is suppressed.

关键词： Phase-field crystal growth diffusion convection lattice kinetics modeling

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A framework for multi-robot motion planning from temporal logic specifications

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Science China(Information Sciences) 2012年第7期55卷 1675-1692页

作者： T.John KOO michael m.QUOTTRUP charles A.CLIFTON Roozbeh IZADI-ZAmANABADI Thomas BAK Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences

We propose a framework for the coordination of a network of robots with respect to formal requirement specifications expressed in temporal logics.A regular tessellation is used to partition the space of interest into a union of disjoint regular and equal cells with finite facets,and each cell can only be occupied by a robot or an *** robot is assumed to be equipped with a finite collection of continuous-time nonlinear closed-loop dynamics to be operated *** robot is then modeled as a hybrid automaton for capturing the finitely many modes of operation for either staying within the current cell or reaching an adjacent cell through the corresponding *** taking the motion capabilities into account,a bisimilar discrete abstraction of the hybrid automaton can be *** the two systems bisimilar,all properties that are expressible in temporal logics such as Linear-time Temporal Logic,Computation Tree Logic,and μ -calculus can be *** planning can then be performed at a discrete level by considering the parallel composition of discrete abstractions of the robots with a requirement specification given in a suitable temporal *** bisimilarity ensures that the discrete planning solutions are executable by the *** demonstration purpose,a finite automaton is used as the abstraction and the requirement specification is expressed in Computation Tree *** model checker Cadence SmV is used to generate coordinated verified motion planning *** autonomous aerial robots are used to demonstrate how the proposed framework may be applied to solve coordinated motion planning problems.

关键词： motion planning multi-robot systems temporal logic hybrid automata discrete abstraction

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Distinct edaphic habitats are occupied by discrete legume assemblages with unique indicator species in the Cape Peninsula of South Africa

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Journal of Plant Ecology 2018年第4期11卷 632-644页

作者： meshack N.Dludlu Samson B.m.Chimphango charles H.Stirton A.muthama muasya Department of Biological Sciences University of Cape TownPrivate Bag X3Rondebosch 7701Cape TownSouth Africa

Aims the Cape Peninsula is a small area(471 km2)situated on the south-westernmost tip of the Core Cape Subregion(CCR)of South *** the Cape Peninsula,Fabaceae are the third most species-rich plant family(162 species)and they have the second highest number of endemic species after the ***,legumes are not the dominant taxa in the *** tend to show patchy distributions within the landscape and different species assemblages usually occupy particular niches at any given *** present study undertook to establish if edaphic factors influence legume species distribution in the Cape Peninsula and to determine the key indicator species for the different *** Soils from 27 legume sites,spanning all major geological substrates of the Cape Peninsula,were analysed for 31 chemical and physi-cal *** species present at each site were recorded and a presence/absence matrix was *** analysis and discriminant function analysis(DFA)were run to group the sites based on overall similarity in edaphic characteristics and to identify the soil parameters contributing towards discriminating the *** correspondence analysis(CCA)was used to test for a cor-relation between legume species compositions and edaphic *** strength of the association between legume species and site groupings based on edaphic properties was assessed using indicator species *** findings Based on similarity in overall soil characteristics,the sites formed three clusters:one comprising sites of sandstone geology,one with dune sand sites and the third cluster comprising sites of both shale and granite geologies(hereafter referred to as soil types).the DFA confirmed the distinctness of these clusters and the CCA showed a significant correlation between legume species composition and edaphic *** key edaphic parameters were clay content,iron(Fe),potassium(K),sulphur(S)and zinc(Zn).these findings reveal

关键词： Fabaceae Core Cape Subregion Cape Peninsula edaphic factors biogeography

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Epidemiology of open fractures in sport: One centre's 15-year retrospective study

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World Journal of Orthopedics 2017年第7期8卷 545-552页

作者： Alexander m Wood Greg A J Robertson Kirsty mac Leod Anna Porter charles m Court-Brown Orthopaedic Department Leeds General Infirmary Edinburgh Orthopaedic Trauma Unit Royal Infirmary of Edinburgh Institute of Naval medicine Newcastle University medical School

AIm To describe the epidemiology of sport-related open fractures from one centre's adult patient population over a 15-year period. mETHODS A retrospective review of a prospectively-collected database was performed: The database contained information all sport-related open fractures, sustained from 1995 to 2009 in the Edinburgh, mid and East Lothian *** Over the 15-year period, there were 85 fractures recorded in 84 patients. The annual incidence of open sport-related fractures was 0.01 per 1000 population. The mean age at injury was 29.2 years(range 15-67). There were 70(83%) males and 14 females(17%).The 6 most common sports were soccer(n = 19, 22%), rugby(n = 9, 11%), cycling(n = 8, 9%), hockey(n = 8, 9%); horse riding(n = 6, 7%) and skiing(n = 6, 7%). The five most common anatomical locations were finger phalanges(n = 30, 35%); tibial diaphysis(n = 19, 23%); forearm(n = 12, 14%); ankle(n = 7, 8%) and metacarpals(n = 5, 6%). The mean injury severity score was 7.02. According to the Gustilo-Anderson classification system, 45(53%) fractures were grade 1; 28(33%) fractures were grade 2; 8(9%) fractures were grade 3a; and 4(5%) fractures were grade 3b. Out of the total number of fractures, 7(8%) required plastic surgical intervention as part of management. The types of flaps used were split skin graft(n = 4), fasciocutaneous flaps(n = 2); and adipofascial flap(n = 1). CONCLUSION We analysed the epidemiology of open fractures secondary to sport in one centre over a 15-year period. Soccer and rugby were the most common causative sports while fractures of the finger phalanx and of the tibial diaphysis were the most common sites. Open fractures are uncommon in sport; however, when they are sustained they usually occur on muddy sport fields or forest tracks and therefore must be treated appropriately. It is important that clinicians and sports therapists have knowledge of these injuries, in order to ensure they are managed optimally.

关键词： Open Fracture Sport Epidemiology Injury Trauma

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measurement of the Average molecular Weight of Cotton Cellulose Crosslinked by a Polycarboxylic Acid at Different pH Using multiple Angle Light Scattering Photometer in a DmAc/LiCl Solvent System

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Journal of Donghua University(English Edition) 2003年第4期20卷 5-7页

作者：毛志平 YANG charles Q College of Chemistry & Chemical Engineering Donghua University Shanghai 200051 Department of Textiles Merchandising and InteriorsUniversity of Georgia Georgiaurable press finishing of cotton fabrics with polycarboxylic acid increases fabric wrinkle-resistance at the expense of its mechanical strength. Severe tensile strength loss is the major disadvantage for wrinkle resistant cotton fabrics. Tensile strength loss of cotton fabric crosslinked by a polycarboxylic acid can be attributed to depolymerization and crosslink of cellulose molecules. Measurement of the molecular weight of cotton fabric before and after crosslinked by polycarboxylic acids can offer a possibility of direct understanding of the depolymerization. In this research a multiple angle laser light scattering photometer was used to determine the absolute molecular weight of cotton fabric treated with BTCA at different pH and then hydrolyzed with 0.5 M NaOH solution at 50℃for 144 h. The results indicate that average molecular weights of cotton fabric treated with polycarboxylic acids at different pH are almost the same.

Durable press finishing of cotton fabrics with polycarboxylic acid increases fabric wrinkle-resistance at the expense of its mechanical strength. Severe tensile strength loss is the major disadvantage for wrinkle resistant cotton *** strength loss of cotton fabric crosslinked by a polycarboxylic acid can be attributed to depolymerization and crosslink of cellulose molecules. measurement of the molecular weight of cotton fabric before and after crosslinked by polycarboxylic acids can offer a possibility of direct understanding of the depolymerization. In this research, amultiple angle laser light scattering photometer was used todetermine the absolute molecular weight of cotton fabric treated with BTCA at different pH and then hydrolyzed with 0. 5 m NaOH solution at 50℃ for 144 h. The results indicate that average molecular weights of cotton fabric treated with polycarboxylic acids at different pH are almost the same.

关键词： cotton cellulose depolymerization laser light scattering photometer molecular weight

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Impact of xylanases on gut microbiota of growing pigs fed corn-or wheat-based diets

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Animal Nutrition 2018年第4期4卷 339-350页

作者： Zhengxiao Zhang Hein m.Tun Ru Li Beatriz J.m.Gonzalez Hannah C.Keenes charles m.Nyachoti Elijah Kiarie Ehsan Khafipour Department of Animal Science University of Manitoba Department of medical microbiology and Infectious Diseases University of Manitoba Department of Animal Bioscience University of Guelph

This study investigated the effects of xylanase supplementations with cereal-based diets on nutrient digestibility and gut microbiota of growing pigs. A total of 96 individually penned pigs(initial BW = 22.7 ± 0.65 kg) were allotted to 12 treatments and subjected to a completely randomized block design experiment. Pigs in each treatment were fed an isocaloric wheat-based or corn-based diet with or without 1 of 5 types of xylanase supplements(XA, XB, XC, XD, XE). On d 42, all piglets were euthanized to obtain ileal and cecal digesta for microbial analysis, which involved high-throughput sequencing of the V1 - V3 regions of 16 S rRNA gene. Corn-and wheat-based diets differed(P ments affected the alpha-and beta-diversities of microbiota in the cecum but not in the ileum. The wheat-based diet increased(P mpared with the corn-based diet. Wheat-based diet also promoted the relative abundance of genus(g.) Succinivibrio while corn-based diet promoted the proportion of family(f.) Veillonellaceae in the community. Among xylanases, only XC within the wheat-based diet altered(P microbiota compared with control. For each cereal-based diet and compared with the controls, xylanase treatments affected(P m(f. Peptostreptococcaceae, order [o.]Streptophyta, f. Clostridiaceae, g. Clostridium and g. Streptococcus) and 8 in the cecum(g. Lactobacillus,g. Streptococcus, class [c.] Clostridia, f. Clostridiaceae, g. megasphaera, g. Prevotella, g. Roseburia and ***). Network analysis showed that across diets under control treatments, Bacteroidetes was the most influential phylum promoting cooperative relationships among members of the ileum and cecum microbiota. Xylanase treatment, however, reduced the influence of Bacteroidetes and promoted a large number of hub taxa majority

关键词： Piglets microbiota Xylanase Arabinoxylans Digestibility

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