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燃料化学学报 2018年第8期46卷 957-966页

作者： Abdulbaset M.Alayat Elena Echeverria David N.Mcllroy Armando G.mcdonald Environmental Science University of IdahoMoscowID83844-3006United States Renewable Materials Program Department of Forest Rangeland and Fire Sciences University of IdahoMoscow ID 83844-1133 United States Department of Physics Oklahoma S

The effect of ethylene diamine tetraacetic acid(EDTA) modification on the physico-chemical properties and catalytic performance of silica nanosprings(NS) supported cobalt(Co) catalyst was investigated in the conversion of syngas(H^(2+) CO) to hydrocarbons by Fischer-Tropsch synthesis(FTS). The unmodified Co/NS and modified Co/NS-EDTA catalysts were synthesized via an impregnation method. The prepared Co/NS and Co/NS-EDTA catalysts were characterized before the FTS reaction by BET surface area,X-ray diffraction(XRD),transmission electron microscopy(TEM),temperature programmed reduction(TPR),X-ray photoelectron spectroscopy(XPS),differential thermal analysis(DTA) and thermogravimetric analysis(TGA) in order to find correlations between physico-chemical properties of catalysts and catalytic performance. FTS was carried out in a quartz fixedbed microreactor(H_2/CO of 2 ∶1,230 ℃ and atmospheric pressure) and the products trapped and analyzed by GC-TCD and GC-MS to determine CO conversion and reaction selectivity. The experimental results indicated that the modified Co/NS-EDTA catalyst displayed a more-dispersed phase of Co_3O_4 nanoparticles(10.9%) and the Co_3O_4 average crystallite size was about 12.4 nm. The EDTA modified catalyst showed relatively higher CO conversion(70.3%) and selectivity toward C_(6-18)(jP-8,jet A and diesel) than the Co/NS catalyst(C_(6-14))(jP-4).

关键词：化学分析煤矿燃烧

The use of woods-run chips in filter socks to control erosion and sedimentation during petroleum development in the Appalachian Basin

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International journal of Sediment Research 2019年第6期34卷 608-615页

作者： Shawn T.Grushecky Louis M.mcdonald Lawrence Osborn West Virginia University Davis College of Agriculture Natural Resources and Design School of Natural Resources Appalachian Hardwood Center at West Virginia University School of Natural Resources Energy Land Management 3. Division of Plant and Soil SciencesEnvironmental Soil Chemistry and Soil Fertility

Filter socks frequently are used for erosion and sediment perimeter control during oil and gas development activities in the Appalachian Basin of the United *** specify the use of composted wood material for sock *** specification,as opposed to non-composted or fresh wood chips(woods-run),has created inefficiencies during well site *** than use fresh wood chips created during site construction,composted chips must be procured and used as filter sock media for erosion and sedimentation *** woods-run chips could be used as filter sock media instead of composted chips,there could be a significant reduction in energy/capital costs,truck traffic,and disposal *** primary objective of this research project was to compare the effectiveness of woodsrun material versus traditionally composted wood chips in controlling sediment transport as well as other chemical and physical parameters in a laboratory *** significant differences in pH(5.96 versus 6.02) or conductivity(0.029 dS/m versus 0.035 dS/m) were found in sediment laden water filtered through woods-run versus composted chips,***,chip particle sizes were outside the allowable limits for composted sock media,and moisture content also was outside the specified limits for woods-run ***(NO) concentrations were significantly higher in woods-run,while phosphorus(P) and potassium(K) concentrations were greater in composted chips;however none of the N,P,or K concentrations were above the regulatory ***,no difference in the filtering efficiency or time was found between woods-run and composted *** laboratory results indicate that current regulations allowing the use of woods-run chips in all but the highest quality watersheds is justified.

关键词： BMP Filter socks Petroleum exploration Marcellus shale Wood chips

Using discriminant analysis to detect intrusions in external communication for self-driving vehicles

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Digital Communications and Networks 2017年第3期3卷 180-187页

作者： Khattab M.Ali Alheeti Anna Gruebler Klaus mcdonald-Maier Embedded and fntelligent Systems Research Laboratory School of Computer Science and Electronic Engineering Universi~ of Essex Wivenhoe ParkColchester C04 3SQ UK University of Anbar College of Computer Science and Information Technology Anbar-Iraq Data Science atAltViz in London - Data Scientist UK School of Computer Science and Electronic Engineering University of Essex Colchester C04 3SQ UK

Security systems are a necessity for the deployment of smart vehicles in our society. Security in vehicular ad hoe networks is crucial to the reliable exchange of information and control data. In this paper, we propose an intelligent Intrusion Detection System （IDS） to protect the external communication of self-driving and semi self-driving vehicles. This technology has the ability to detect Denial of Service （DOS） and black hole attacks on vehicular ad hoe networks （VANETs）. The advantage of the proposed IDS over existing security systems is that it detects attacks before they causes significant damage. The intrusion prediction technique is based on Linear Discriminant Analysis （LDA） and Quadratic Diseriminant Analysis （QDA） which are used to predict attacks based on observed vehicle behavior. We perform simulations using Network Simulator 2 to demonstrate that the IDS achieves a low rate of false alarms and high accuracy in detection.

关键词： Secure communication Vehicle ad hoc networks IDS Self-driving vehicles Linear and quadratic discriminant analysis

Constraining the links between the Himalayan belt and the Central Myanmar Basins during the Cenozoic:An integrated multi-proxy detrital geochronology and trace-element geochemistry study

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Geoscience Frontiers 2021年第2期12卷 657-676页

作者： F.Arboit M.Min D.Chew A.mitchell K.Drost E.Badenszki j.S.Daly Department of Geology Trinity College DublinDublinIreland Department of Geology University of MandalayMandalayMyanmar Myanmar Precious Resources Group and 20 Dale Close OxfordOX11TUUK UCD School of Earth Sciences University College DublinDublinIreland iCRAG(Irish Centre for Research in Applied Geosciences) University College DublinDublinIreland Department of Earth Science Khalifa UniversityAbu DhabiUnited Arab Emirates

Geological and tectonic analysis of the Eastern Himalayan basins has given rise to a decade-long debate on the geodynamic evolution of the Burmese terrane and on the extent of reorganization of the main SE Asia drainage ***,the influence of the Himalayan belt on the Central Myanmar Basin(CMB)system remains poorly documented,although it is key to providing more accurate models for the evolution of the Himalayan-Burmese *** this contribution,we present geochronological,isotopic and geochemical analysis from 2500 zircon,1700 titanite,700 rutile and 850 apatite detrital grains from fifteen Cenozoic siliciclastic samples and one Cretaceous igneous *** samples were collected within the fore-and back-arc basins of the Central Myanmar Basin domain(CMB)to constrain the provenance,maximum depositional ages,and depositional environments of the west Burma *** key lithological units,the Sadwingyi,Ketpanda,Wabo Chaung,Gwegon,Minwun,Padaung,Okmintaung and Irrawaddy formations have detrital age spectra spanning from the Miocene to *** entire data set has common age peaks at ca.20,40,60,90,100 Ma,with about 80%of the U–Pb ages younger than ca.140 Ma and only ca.1%of the grains predating ca.3.0 *** results shed light on the current ambiguities on the transport pathways of Himalayan detritus in the *** show that the fore-arc basin was open to the trench and fed by the unroofing of both the Wuntho Popa volcanic arc to the east and possibly from the Burmese basement and/or from Himalayan-derived Bengal Fan detritus to the west during the Eocene,from at least ca.44 Ma to before ca.39 *** show that the west Burma Terrane was partitioned into pull-apart basins such as the Minwun Basin,which during the Oligocene recorded the first evidence of a new source contribution into the CMB at ca.27 *** new source is characterized by detritus highly compatible with the SE Asia basement rocks,which we suggest corresponds to the initiation of t

关键词： Geochronology Geochemistry Himalaya Indo Burma Range Myanmar Provenance

Monitoring real time polymorphic transformation of sulfanilamide by diffuse reflectance visible spectroscopy

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journal of Pharmaceutical Analysis 2016年第3期6卷 179-183页

作者： Tracy O.Ehiwe Bruce D.Alexander john C.mitchell Martin j.Snowden Laura j.Waters Medway Centre for Formulation Science Faculty of Engineering and Science University of Greenwich at Medway School of Applied Sciences University of Huddersfield

This study investigated the development of a novel approach to surface characterization of drug poly- morphism and the extension of the capabilities of this method to perform ＇real time＇ in situ measure- ments. This was achieved using diffuse reflectance visible （DRV） spectroscopy and dye deposition, using the pH sensitive dye, thymol blue （TB）. Two polymorphs, SFN-β and SFN-γ, of the drug substance sulfanilamide （SFN） were examined. The interaction of adsorbed dye with polymorphs showed different behavior, and thus reported different DRV spectra. Consideration of the acid/base properties of the morphological forms of the drug molecule provided a rationalization of the mechanism of differential coloration by indicator dyes. The kinetics of the polymorphic transformation of SFN polymorphs was monitored using treatment with TB dye and DRV spectroscopy. The thermally-induced transformation fitted a first-order solid-state kinetic model （R2=0.992）, giving a rate constant of 2.43 × 10^- 2 s 1.

关键词： Polymorphic transformation Sulfanilamide Diffuse reflectance visible spectroscopy Powder X-ray diffraction Differential scanning calorimetry

Adoption of Improved Rice Varieties in the Global South:A Review

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Rice science 2023年第3期30卷 186-206,I0021-I0034页

作者： julia CHECCO Fathin Ayuni AZIZAN jaquie mitchell Ammar Abdul AZIZ School of Agriculture and Food Sciences The University of QueenslandGatton 4343QueenslandAustralia Department of Agrotechnology Faculty of Mechanical Engineering and TechnologyUniversiti Malaysia PerlisArau 02600PerlisMalaysia

Improved rice varieties(IRVs)play a significant role in establishing food security and improving livelihood in the Global South since its introduction in the ***,the adoption of new IRVs has remained relatively *** low adoption poses a challenge to rice-producing and consuming countries as they are increasingly threatened by production shortages,malnutrition,and poor rice *** empirical studies have attempted to identify the determinants influencing the adoption of IRVs by distinguishing the characteristics between adopters and *** review showed a consensus on the important determinants influencing the adoption of IRVs in the Global *** synthesized from 99 studies suggested that variables(farm size,education,information access and farm location)examined extensively are not necessarily the most important determinants of adoption when undertaking a weighted ***,source of seed and technology-related attributes(perceived yield,maturity,ease of use,marketability and technical efficiency)are more important determinants of adoption,with determinants changing according to adoption type(probability or intensity of adoption),variety type and *** recommendations for future adoption studies include:incorporating more technology-specific variables,increasing research for overlooked regions and variety types,shifting away from predominant static analysis by capturing the dynamics of the adoption process,and considering the potential biases in *** review will facilitate the development of targeted interventions and policies that promote IRV adoption in the Global South.

关键词： technology adoption improved rice variety systematic literature review the Global South

Effects of far-off and close-up transition cow feeding on uterine health,postpartum anestrous interval,and reproductive outcomes in pasture-based dairy cows

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journal of Animal Science and Biotechnology 2020年第2期11卷 493-503页

作者： S.Meier j.K.Kay B.Kuhn-Sherlock A.Heiser M.D.mitchell M.A.Crookenden M.Vailati Riboni j.j.Loor j.R.Roche DairyNZ Limited Private Bag 3221Hamilton 3240New Zealand AgResearch Hopkirk Research InstituteGrasslands Research CentrePalmerston North 4442New Zealand Centre for Children’s Health Research Queensland University of TechnologyLevel 662 Graham StreetSouth BrisbaneQueensland 4101Australia DairyNZ Limited c/o University of Auckland3A Symonds StAuckland 1010New Zealand Department of Animal Sciences University of IllinoisUrbana 61801USA Ministry for Primary Industries-ManatūAhu Matua Charles Ferguson TowerPipiteaWellington 6140New Zealand School of Biological Sciences University of AucklandPrivate Bag 92019Auckland 1142New Zealand

Background:In seasonal,pasture-based,dairy production systems,cows must recover from calving and become pregnant within two to 3 *** achieve this,the uterus must involute and ovulation must occur and continue at regular *** these processes are affected by the cows’nutritional or metabolic status post-calving,the objective of this study was to evaluate the effect of cow feeding strategies on uterine health,the length of postpartum anestrous interval,and reproductive *** treatments consisted of two feeding strategies during late-lactation and early dry period(far-off period;starting 4-month pre-calving)and three close-up dry period feeding regimes(1-month pre-calving)in a 2×3 factorial *** randomly assigned 150 cows to one of two far-off *** late lactation,the herds(n=75 cows per herd)were either control-fed(Controlfed)or over-fed(Overfed)to achieve a low or high body condition score(4-month pre-calving;BCS;~4.25 and^4.75;10-point scale)at cessation of *** each of these treatments,three feeding levels were applied during the close-up period(1-month pre-calving):~65%(Feed65),~90%(Feed90),or^120%(Feed120)of metabolizable energy(ME)intakes relative to pre-calving ***:Uterine health improved(***(PMN)cells declined)with increased feeding during the close-up period for cows in the Overfed *** reverse was evident for the Controlfed group with the greatest PMN at the highest intakes during the close-up *** postpartum anoestrous interval(PPAI)was shorter in cows from the Overfed group when moderately fed(Feed90)during the close-up period;in comparison,the PPAI was shorter in the Controlfed group,when those cows were overfed in the close-up period(Feed120).The cows in the Overfed treatment had greater conception and pregnancy rates if cows had moderate dry matter intakes(Feed90)during the close-up period;these reproductive variables were less under excessive feed inta

关键词： Close-up Dairy cows Far-off Reproduction Transition period

How Can Commodity Quality Be Ensured and Relevant Disputes Be Settled?

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China's Foreign Trade 2016年第4期 36-37页

作者： j.mitchell

China,the big factory offering various commodities to companies and individuals all over the world,is attracting more and more merchants purchasing goods in various ways,through agents,on site,via modern communication,*** essential concern of these merchants is the quality of these *** can the commodity quality be ensured?If there are

关键词： more Be How Can Commodity Quality Be Ensured and Relevant Disputes Be Settled

Invasion reproductive numbers for periodic epidemic models

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Infectious Disease Modelling 2019年第1期4卷 124-141页

作者： Christopher mitchell Christopher Kribs Department of Mathematics Tarleton State UniversityStephenvilleTX 76402USA Department of Mathematics University of Texas at ArlingtonArlingtonTX 76019-0408USA

There are many cases within epidemiology where infections compete to persist within a *** studying models for such cases,one of the goals is to determine which infections can invade a population and persist when other infections are already resident within the *** reproductive numbers(IRN),which are tied to the stability of boundary endemic equilibria,can address this *** reinterpreting resident infections epidemiologically,this study extends methods for finding IRNs to periodic systems,and presents some examples which illustrate the often complex computations *** identify conditions under which a simple time-average can be used to derive IRNs,and apply the methods to examine how seasonal fluctuations in influenza incidence facilitate the year-round persistence of bacterial respiratory infections.

关键词： Mathematical epidemiology Periodic models Basic reproductive number

Taxonomic and metabolic shifts in the Coorong bacterial metagenome driven by salinity and external inputs

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journal of Oceanology and Limnology 2018年第6期36卷 2033-2049页

作者： Kelly NEWTON Thomas C.jEFFRIES Renee j.SMITH justin R.SEYMOUR Laurent SEURONT james G.mitchell School of Biological Sciences Flinders University School of Science and Health Western Sydney University Flinders Centre for Innovation in Cancer Flinders University Climate Change Cluster University of Technology Sydney Centre National de la Recherche Scientifi que Laboratoire d'Océanologie et de Géosciences

The Coorong estuary lies at the terminus of Australia's largest river system, the Murray-Darling; both are strongly influenced by human activities; including farming and extensive flow modification. Metagenomic approaches were used to determine the planktonic bacterial community composition and potential metabolic function at two extremes in the Coorong, the river mouth which exhibits marine-like salinity, and the hypersaline upper-reaches of the estuary. Significant shifts in taxa and metabolic function were seen between the two sites. The river mouth exhibited an increase in abundance of R hodobacteriaceae and Alteromonadaceae; families readily able to adapt to change in nutrient conditions; and the potentially pathogenic families B rucellaceae, Enterobacteriaceae and Vibrionaceae. Metabolisms over-represented include motility and chemotaxis, RNA metabolism and membrane transport, all of which are involved in actively searching for and obtaining nutrients. Also over-represented were metabolisms involved in population succession and stress response. An over-representation of taxa and metabolisms indicative of environmental change is reflective of anthropogenically af fected riverine input. In the hypersaline upper reaches of the estuary, the halophilic family Ectothiorhodospiraceae was over-represented, as were the families Flavobacteriaceae, Cytophagaceae and Nocardioidaceae, members of which are able to survive over a wide salinity range. Metabolisms over-represented here were reflective of increased bacterial growth, characteristic of hypersaline environments, and included DNA metabolism, nucleotide and nucleoside synthesis and cell cycle. Coorong metagenomes clustered taxonomically and metabolically with other planktonic metagenomes, but remained an outlier of this group with only 71% and 84% similarity, respectively. This indicates that the Coorong exhibits a unique planktonic bacterial community that is influenced by riverine input at the river mouth and sali

关键词： hypersaline estuary bacteria taxonomy metabolic potential