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Particuology 2016年第3期14卷 1-18页

作者： Cai y. Ma j.ng j. Liu Xue Z. Wang Institute of Particle Science and Engineering School of Chemical and Process Engineering University of Leeds Leeds 1.52 9JT United Kingdom School of Chemistry.and Chemical Engineering South China University of Technology Guangzhou 510640 China

Cry.tal morphology.is known to be of great importance to the end-use properties of cry.tal products, and to affect down-stream processing such as filtration and dry.ng. However, it has been previously.regarded as too challenging to achieve automatic closed-loop control. Previous work has focused on controlling the cry.tal size distribution, where the size of a cry.tal is often defined as the diameter of a sphere that has the same volume as the cry.tal. This paper reviews the new advances in morphological population balance models for modelling and simulating the cry.tal shape distribution （CShD）, measuring and estimating cry.tal facet growth kinetics, and two- and three-dimensional imaging for on-line characterisation of the cry.tal morphology.and CShD. A framework is presented that integrates the various components to achieve the ultimate obj.ctive of model-based closed-loop control of the CShD. The knowledge gaps and challenges that require further research are also identified.

关键词： Cry.tal morphology.Cry.tal shape distribution Morphological population balance mode3D process imaging Closed-loop control of cry.tal shapeCry.tal facet growth kinetics

Sy.thesis of coral-like structures of Pr-y. co-doped y.G: Structural,optical, magnetic and antimicrobial properties

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j.urnal of Rare Earths 2024年第3期42卷 543-554,I0004页

作者： A.Fernandez Francisca P.Arauj. y.Guerra S.Castro-Lopes j.Matilla-Arias Idglan S.de Lima Edson C.Silva-Filho j.sy.A.Osaj.ma F.Guerrero R.Pena-Garcia Federal University.of Piau Graduate Program in Materials Science and EngineeringTeresinaPIBrazil Federal Rural University.of Pernambuco Academic Unit of Cabo de Santo AgostinhoCabo de Santo AgostinhoPEBrazil Federal University.of Piaui Department of PhysicTeresinaPBrazil Federal University.of Pernambuco Graduate Program in Materials ScienceRecifePEBrazil University.of Granma Departmentof Basic Sciences and Applied InformaticsFaculty of Technical SciencesBayamoCuba Federal University.of Amazonas Department of PhysicManausAMBrazil Federal University.of Pernambuco Department of PhysicRecifePEBrazil

Coral-like structures of the y.(3-x)Pr_(x)Fe_(5-y.y._(y.O_(12),(0.00 ≤ x ≤ 0.04, 0.00 ≤ y.≤ 0.02) compound were sy.thesized using the sol-gel method. Structural investigation certified the y.G cubic cry.tal structure formation, without any.secondary.phase. It is shown that, the relatively.large ionic radius of the dopant cations results in an expansion of the lattice parameter, variations in the Iona-O-Iondangle, Iona-O,Iond-O and Ionc-O bond distances and decrease in the average cry.tallite size. Fourier transform infrared(FTIR) and Raman measurements are essential to testify.the single-phase formation of y.G cry.tal structure and are observed changes in the stretching and vibrational modes, respectively. The morphological study. energy.dispersive spectroscopy.EDS) spectra and textural properties show corallike structures, peaks associated with Pr^(3+) and y.^(3+) atoms and the effect of dopants on surface area,diameter, and pore volume, respectively. The optical analy.is from diffuse reflectance spectra witnessed an increase in the optical gap band, a decrease in Urbach energy.and blue shift in the charge transfer,correlated with the expansion of the unit cell due to the dopant's insertion in the y.G structure. A ty.ical ferrimagnetic behavior is exhibited by.the y.(3-x)Pr_(x)Fe_(5-y.y._(y.O_(12)compound. The saturation magnetization(M_(s)), cubic anisotropy.constant(K_(1)) and coercive field(H_(c)) increase with the Pr^(3+)cations content, as consequence of their magnetic nature and distribution around of Fe^(3+)ions due to the coexistence with the y.^(3+). Finally. for the first time, antibacterial tests by.mean of the direct contact method were performed for y.G co-doped with Pr^(3+)and y.^(3+)and it is shown that, relatively.high dosages of Pr^(3+) cations favored the activity.against S. aureus, therefore, a new biological property.for y.G doped with rare earths is presented.

关键词： y.trium iron garnet(y.G) Coral-like structures Rare earths Band gap energy Magnetic properties Antimicrobial properties

Machine Learning and Statistical Analy.is in Groundwater Monitoring for Total Dissolved Solids Assessment in Winkler County. Texas

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j.urnal of Geoscience and Environment Protection 2024年第6期12卷 1-29页

作者： Azuka I. Udeh Osay.men j. Imarhiagbe Erepamo j. Omietimi Abdulqudus O. Mohammed Oluwatomilola Andre-Obay.nj. Department of Geoscience University of Texas Permian Basin Odessa USA Department of Geology University of Pretoria Pretoria South Africa Department of Geology University of Benin Benin Nigeria

This research aims to develop reliable models using machine learning algorithms to precisely.predict Total Dissolved Solids (TDS) in wells of the Permian basin, Winkler County. Texas. The data for this contribution was obtained from the Texas Water Development Board website (TWDB). Five hundred and ninety.three samples were obtained from two hundred and ninety.eight wells in the study.area. The wells were drilled at different county.locations into five aquifers, including Pecos Valley. Dockum, Capitan Reef, Edward Trinity. and Rustler aquifers. A total of fourteen different water quality.parameters were used, and they.include Potential hy.rogen (pH), Sodium, Chloride, Magnesium, Fluoride, TDS, Specific Conductance, Nitrate, Total Hardness, Calcium, Temperature, Well Depth, Sulphate, and Bicarbonates. Four machine learning regression algorithms were developed to get a good model to help predict TDS in this area: Decision Tree regression, Linear regression, Support Vector Regression, and K-nearest neighbor. The study.showed that the Decision Tree produced the best model with attributes like the coefficient of determination R2 = 1.00 and 0.96 for the training and testing, respectively. It also produced the lowest score of mean absolute error MAE = 0.00 and 0.04 for training and testing, respectively. This study.will reduce the cost of obtaining different water quality.parameters in TDS determination by.leveraging machine learning to use only.the parameters contributing to TDS, thereby.helping researchers obtain only.the parameters necessary.for TDS prediction. It will also help the authorities enact policies that will improve the water quality.in areas where drinking water availability.is a challenge by.providing important information for monitoring and assessing groundwater quality.

关键词： Machine Learning Regression Aquifers Winkler County Sinkholes

Study.of neutron response for two hy.rid RPC setups using the GEANT4 MC simulation approach

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Chinese Phy.ics C 2009年第10期33卷 887-891页

作者： M. j.mil j. T. Rhee y. j. j.on Institute for Advanced Phy.ics Konkuk University Liquid Cry.tal Research Center Konkuk University

The present article describes a detailed neutron simulation study.in the energy.range 10^-10 MeV to 1.0 GeV for two different RPC configurations. The simulation studies were taken by.using the GEANT4 MC code. Aluminum was utilized on the GND and readout strips for the （a） Bakelite-based and （b） glass-based RPCs. For the former ty.e of RPC setup the neutron sensitivity.for the isotropic source was Sn = 2.702 × 10^-2 at En = 1.0 GeV, while for the latter ty.e of RPC, the neutron sensitivity.for the same source was evaluated as Sn = 4.049 × 10^-2 at En = 1.0 GeV. These results were further compared with the previous RPC configuration in which copper was used for ground and pickup pads. Additionally.A1 was employ.d at （GND＋strips） of the phosphate glass RPC setup and compared with the copper-based phosphate glass RPC. Good agreement with sensitivity.values was obtained with the current and previous simulation results.

关键词： resistive plate chambers neutron sensitivity GEANT4 Monte Carlo simulation

Habitat relationships of reptiles in pine beetle disturbed forests of Alabama,*** guidelines for a modified drift-fence sampling method

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Current Zoology 2010年第4期56卷 411-420页

作者： W. B. SUTTON y. WANG C. j. SCHWEITZER Department of Natural Resources and Environmental Sciences Alabama A＆M University Normal AL 35762 USA USDA Forest Service Southern Research Station PO Box 1568 Normal AL 35762 USA

Understanding vertebrate habitat relationships is important to promote management strategies for the longterm conservation of many.species. Using a modified drift fence method, we sampled reptiles and compared habitat variables within the William B. Bankhead National Forest （BNF） in Alabama, U.S.A from April 2005 to j.ne 2006. We captured 226 individual reptiles representing 19 species during 564 total trap nights. We used canonical correspondence analy.is to examine habitat associations for the reptiles sampled and we detected a distinct habitat gradient ranging from sites with greater litter depth and percent canopy.cover to more open sites with greater woody. herbaceous, and coarse woody.debris （CWD） coverage, and CWD volume. Little brown skinks Scincella lateralis and eastern worm snakes Carphophis a. arnoenus were associated with sites with greater litter depth and canopy.cover, whereas eastern fence lizards Sceloporus undulatus, copperheads Agkistrodon contortrix, and gray.ratsnakes Pantherophis spiloides were associated with sites possessing greater CWD coverage and volume. We found that disturbances due to the southern pine beetle Dendroctonus frontalis were likely.important for influencing reptile distributions through the creation of canopy.gaps and fallen coarse woody.debris. Compared to other studies, our modified drift-fence trap technique was successful for sampling larger snake species （66 snakes in 564 trap nights）. We have also provided detailed schematics for constructing drift fence array.and box traps used in this study

关键词： William B. Bankhead National Forest Canonical Correspondence Analy.is Dendroctonusfrontalis Drift-fence Array. Reptiles Southern Pine Beetle

Phosphorus export by.runoff from agricultural field plots with different crop cover in Lake Taihu watershed

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j.urnal of Environmental Sciences 2001年第4期13卷 502-507页

作者： y.n, W.-j. Huang, M.-x. Zhang, S. Tang, y.-j. Dept. of Envrn. Biogeochemistry Inst.Geographic Sci./Nat. Rsrc. Res. Chinese Academy of Sciences Beijing 100101 China

Runoff and soil losses from agricultural fields are investigated as maj.r nonpoint sources of phosphorus (P) entering lakes of Eastern China. There is relatively.little information on P transport from ricefield and cropland of Lake Taihu watershed in Eastern China. Soil and P in surface runoff from a series of plots in the watershed were evaluated under simulated rainfall conditions. The obj.ctives of this study.were to evaluate the effects of crop cover, slope, and fertilizer application on P concentrations in surface runoff and eroded soil. Accumulated sediment y.elds varied from 7.1 to 300 g/m2 for croplands, depending on management practices. For all experiment plots, weighted average concentrations of total-P (TP), dissolved P (DP) and particulate P (PP) are much higher than 0.02 mg/L, the limiting concentration for lake water. This result showed the potential contamination of lake water from agricultural surface runoff. Accumulated TP losses were 3.8 and 18.8 mg/m2 for ricefield and cropland, respectively. The estimated annual loss of TP was 0.74 kg/(hm2 · a) for cropland. Most of P loss is in the PP form, which accounts for more than 90% of TP loss for cropland.

关键词： Concentration (process) Crops Lakes Phosphorus Sediments Soils Watersheds

Vibration induced flow in hoppers:DEM 2D poly.on model

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Particuology 2008年第6期6卷 455-466页

作者： Feras y. Fraige Paul A. Langston Andrew j. Matchett j.hn Dodds Faculty.of Mining and Environmental Engineering Al-Hussein Bin Talal University Jordan Chemical and Environmental Engineering Nottingham University University Park Chemical Engineering University of Teesside Centre RAPSODEE Ecole Des Mines

A two-dimensional discrete element model （DEM） simulation of cohesive poly.onal particles has been developed to assess the benefit of point source vibration to induce flow in wedge-shaped hoppers. The particle-particle interaction model used is based on a multi-contact principle. The first part of the study.investigated particle discharge under gravity.without vibration to determine the critical orifice size （Bc） to j.st sustain flow as a function of particle shape. It is shown that poly.onal-shaped particles need a larger orifice than circular particles. It is also shown that Bc decreases as the number of particle vertices increases. Addition of circular particles promotes flow of poly.ons in a linear manner. The second part of the study.showed that vibration could enhance flow, effectively.reducing Bc. The model demonstrated the importance of vibrator location （height）, consistent with previous continuum model results, and vibration amplitude in enhancing flow.

关键词： Bulk solids Vibration DEM Hoppers Materials handling Poly.on

Metrology.for sub-Ray.eigh-length target positioning in~10^(22)W/cm^(2)laser-plasma experiments

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High Power Laser Science and Engineering 2024年第3期12卷 90-105页

作者： E.A.Vishny.kov A.Sagisaka K.Ogura T.Zh.Esirkepov B.Gonzalez-Izquierdo C.D.Armstrong T.A.Pikuz S.A.Pikuz W.y.n T.M.j.ong S.Singh P.Hadj.solomou O.Finke G.M.Grittani M.Nevrkla C.M.Lazzarini A.Vely.an T.Hay.kawa y.Fukuda j.K.Koga M.Ishino K.Kondo y.Miy.saka A.Kon M.Nishikino y.V.Nosach D.Khikhlukha I.P.Tsy.vintsev D.Kumar j.Nej.l D.Margarone P.V.Sasorov S.Weber M.Kando H.Kiriy.ma y.Kato G.Korn K.Kondo S.V.Bulanov T.Kawachi A.S.Pirozhkov ELI Beamlines Facility The Extreme Light Infrastructure ERICDolníBrežanyCzech Republic Kansai Institute for Photon Science(KPSI) QSTKyotoJapan Central Laser Facility Rutherford Appleton LaboratorySTFCHarwell OxfordDidcotUK Institute for Open and Transdisciplinary.Research Initiatives Osaka UniversityOsakaJapan HB11 Energy.Holdings FreshwaterAustralia Key.Laboratory.for Laser Plasmas(Ministry.of Education) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghaiChina Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghaiChina Institute of Plasma Phy.ics ASCR PragueCzech Republic FZU-Institute of Phy.ics ASCR PragueCzech Republic Czech Technical University.in Prague FNSPEPragueCzech Republic Institute of Laser Engineering Osaka UniversityOsakaJapan Institute of Phy.ics National Academy of Sciences of UkraineKyivUkraine ISTEQ AR YerevanArmenia

Tight focusing with very.small f-numbers is necessary.to achieve the highest at-focus ***,tight focusing imposes strong demands on precise target positioning in-focus to achieve the highest on-target irradiance We describe several near-infrared,visible,ultraviolet and soft and hard X-ray.diagnostics employ.d in a~10^(22)W/cm^(2)laser±plasma *** used nearly.10 j.total energy.femtosecond laser pulses focused into an approximately..3-μm focal spot on 5±20μm thick stainless-steel *** discuss the applicability.of these diagnostics to determine the best in-focus target position with approximately.5μm accuracy.i.e.,around half of the short Ray.eigh length)and show that several diagnostics(in particular,3ωreflection and on-axis hard X-ray.)can ensure this *** demonstrated target positioning within several micrometers from the focus,ensuring over 80%of the ideal peak laser intensity.*** approach is relatively.fast(it requires 10±20 laser shots)and does not rely.on the coincidence of low-power and high-power focal planes.

关键词： laser-plasma interaction precise target positioning spectroscopy ultra-high intensity X-ray.

Analy.is of ancient mass extinction recoveries in marine environments: generating strategies for managing outcomes of the current mass extinction

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National Science Review 2024年第1期11卷 8-10页

作者： David j.Bottj.r Department of Earth Sciences University of Southern California

The defining feature of a mass extinction and its associated recovery.is the global amount of extinction that occurred[1]. However, there is finer-scale detail to the story. as seen in the ongoing modern mass extinction(the sixth mass extinction), which exhibits variable effects among marine ecosy.tems and environments, and hence geographic areas [1].

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Global weirding at mass extinction horizons

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National Science Review 2024年第1期11卷 10-12页

作者： Gregory.j.Retallack Department of Earth Sciences University of Oregon

A strong motivation for study.ng mass extinctions is understanding how current climatic and biodiversity.crises will affect creatures living on land such as ourselves. Perhaps the question is: how bad can it get? In that case, terrestrial Permian-Triassic mass extinctions are an irresistible worst-case scenario [1].

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