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Two-Stream Approximation to the Radiative Transf.r Equation:A New Improvement and comparative Accuracy with Existing Methods

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Advances in Atmospheric Sciences 2024年第2期41卷 278-292页

作者： f.Momo TEMGOUA L.Akana NGUIMDO DNJOMO Environmental Energy Technologies Laboratory(EETL) Faculty of SciencesUniversity of YaoundéPO Box 812 YaoundéCameroon Department of.Electrical and Electronic Engineering Faculty of Engineering and TechnologyUniversity of BueaPO Box 63 BueaCameroon

Mathematical modeling of.the interaction between solar radiation and the Earth's atmosphere is f.rmalized by the radiative transf.r equation(RTE), whose resolution calls f.r two-stream approximations among other methods. This paper proposes a new two-stream approximation of.the RTE with the development of.the phase f.nction and the intensity into a third-order series of.Legendre polynomials. This new approach, which adds one more term in the expression of.the intensity and the phase f.nction, allows in the conditions of.a plane parallel atmosphere a new mathematical f.rmulation of.γparameters. It is then compared to the Eddington, Hemispheric constant, Quadrature, combined Delta f.nction and Modif.ed Eddington, and second-order approximation methods with ref.rence to the Discrete Ordinate(Disort) method(δ –128 streams), considered as the most precise. This work also determines the conversion f.nction of.the proposed New Method using the f.ndamental def.nition of.two-stream approximation(f.TSA) developed in a previous work. Notably,New Method has generally better precision compared to the second-order approximation and Hemispheric constant methods. compared to the Quadrature and Eddington methods, New Method shows very good precision f.r wide domains of.the zenith angle μ 0, but tends to deviate f.om the Disort method with the zenith angle, especially f.r high values of.optical thickness. In spite of.this divergence in ref.ectance f.r high values of.optical thickness, very strong correlation with the Disort method(R ≈ 1) was obtained f.r most cases of.optical thickness in this study. An analysis of.the Legendre polynomial series f.r simple f.nctions shows that the high precision is due to the f.ct that the approximated f.nctions ameliorate the accuracy when the order of.approximation increases, although it has been proven that there is a limit order depending on the f.nction f.om which the precision is lost. This observation indicates that increasing the order of.app

关键词： Radiative Transf.r Equation two-stream method Legendre polynomial optical thickness moments of.specif.c intensity conversion f.nction transmittance ref.ectance

Ef.ects of.dust controls on respirable coal mine dust composition and particle sizes:case studies on auxiliary scrubbers and canopy air curtain

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International Journal of.coal Science & Technology 2024年第3期11卷 86-101页

作者： f.Animah c.Keles W.R.Reed E.Sarver Department of.Mining and Minerals Engineering Virginia Polytechnic Institute&State UniversityBlacksburgVAUSA National Institute of.Occupational Saf.ty and Health(NIOSH) PittsburghPAUSA

control of.dust in underground coal mines is critical f.r mitigating both saf.ty and health *** decades,the National Institute of.Occupational Saf.ty and Health(NIOSH)has led research to evaluate the ef.ectiveness of.various dust control technologies in coal *** studies have included the evaluation of.auxiliary scrubbers to reduce respirable dust downstream of.active mining and the use of.canopy air curtains(cAcs)to reduce respirable dust in key operator *** detailed dust characterization was not a f.cus of.such studies,this is a growing area of.*** preserved f.lter samples f.om three previous NIOSH studies,the current work aims to explore the ef.ect of.two dif.erent scrubbers(one wet and one dry)and a roof.bolter cAc on respirable dust composition and particle size *** this,the preserved f.lter samples were analyzed by thermogravimetric analysis and/or scanning electron microscopy with energy dispersive *** indicate that dust composition was not appreciably af.ected by either scrubber or the ***,the wet scrubber and cAc appeared to decrease the overall particle size *** an ef.ect of.the dry scrubber was not consistently observed,but this is probably related to the particular sampling location downstream of.the scrubber which allowed f.r signif.cant mixing of.the scrubber exhaust and other return *** f.om the insights gained with respect to the three specif.c dust control case studies revisited here,this work demonstrates the value of.preserved dust samples f.r f.llow-up investigation more broadly.

关键词： Respirable dust Dust control SEM–EDX Scrubber canopy air curtain Silica

Mathematical modeling and simulations of.stress mitigation by coating polycrystalline particles in lithium-ion batteries

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 947-962页

作者： N.IQBAL J.cHOI S.f.SHAH c.LEE S.LEE Department of.Mechanical Roboticsand Energy EngineeringDongguk University-SeoulSeoul 04620Republic of Korea

A chemo-mechanical model is developed to investigate the ef.ects on the stress development of.the coating of.polycrystalline Ni-rich LiNixMnyco_(z)O_(2)(x≥0.8)(NMc)particles with poly(3,4-ethylenedioxythiophene)(PEDOT).The simulation results show that the coating of.primary NMc particles signif.cantly reduces the stress generation by ef.iciently accommodating the volume change associated with the lithium dif.usion,and the coating layer plays roles both as a cushion against the volume change and a channel f.r the lithium transport,promoting the lithium distribution across the secondary particles more ***,the lower stif.ness,higher ionic conductivity,and larger thickness of.the coating layer improve the stress *** paper provides a mathematical f.amework f.r calculating the chemo-mechanical responses of.anisotropic electrode materials and f.ndamental insights into how the coating of.NMc active particles mitigates stress levels.

关键词： lithium-ion battery(LIB) polycrystalline particle coating f.nite element simulation Ni-rich LiNixMnyco_(z)O_(2)(x>0.8)(NMc)

Adsorption of.pharmaceutical pollutants on Zncl_(2)-activated biochar f.om corn cob:Ef.iciency,selectivity and mechanism

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Journal of.Bioresources and Bioproducts 2024年第1期9卷 58-73页

作者： christian f.Varela L.c.Moreno-Aldana Yazmin Yaneth Agámez-Pertuz Department of.chemistry National University of ColombiaAv.Carrera 30 No.45-03BogotáD.C.Colombia Department of.Biology and chemistry University of the Llanoskm 12 road to Puerto LópezVillavicencioColombia

The occurrence of.pharmaceuticals in water bodies and drinking water poses risks f.r the envi-ronment and human health,thus it is necessary to study methodologies that allow the ef.icient removal of.these *** this work,corn cob-derived biochar was obtained by Zncl_(2)-activation,and subsequent carbonization at 700℃.The ef.ect of.contact time,temperature,pH,and initial concentration on the adsorption capacity of.acetaminophen(AcE)and amoxicillin(AMX)was determined through batch *** addition,the kinetics,isotherms,and ther-modynamics parameters were *** activated biochar exhibited a maximum adsorp-tion capacity of.332.08 mg/g f.r AcE and 175.86 mg/g f.r *** adsorption kinetics and adsorption isotherm of.AcE corresponded to the pseudo-second order and Langmuir model,***,pseudo-f.rst-order kinetics and the f.eundlich isotherm model were well-f.tted to AMX *** AcE and AMX co-adsorption had a synergistic ef.ect on AMX but an antagonistic ef.ect on AcE removal,achieving a maximum adsorption capacity of.193.51 and 184.58 mg/g,*** the other hand,f.xed-bed column experiments showed that the adsorption capacity depends on the inf.uent concentration,and the breakthrough curve f.ts the Thomas and Yoon-Nelson *** mechanism adsorption studies showed that surf.ce inter-actions(hydrogen bonding f.rmation and n-𝜋interactions)are the main driving f.rces f.r the adsorption process,and pore f.lling is the rate-limiting *** this way,the prepared biochar exhibits a high potential f.r the adsorption of.pharmaceutical compounds f.om water.

关键词： Biochar Adsorption Acetaminophen Amoxicillin Wastewater treatment

characterization of.conception drawing in architecture to f.ce technological mediations

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f.ontiers of.Architectural Research 2024年第3期13卷 425-438页

作者： Hugo c.Gomez-Tone Javier f.Raposo Grau Departamento de Ideación Gráf.ca Arquitectónica Universidad Politécnica de MadridMadrid 28040Spain Departamento de Arquitectura Universidad Nacional de San Agustín de ArequipaArequipa 04001Peru

The conception drawing in architecture is that allows to initiate the architectural thinking,visualizing,and discovering the f.rst *** drawing has traditionally been given as an act of.linking and collaboration between thought,sight,and the movement of.the hands with a *** and recognizing its characteristics will make it possible to deal with any mediation of.inf.rmation *** establish such characteristics,three case studies were carried *** analysis was made of.the conception drawings and interviews by the Pritzker Prize laureates:Ando,Hadid and *** condition and f.ur characteristics have been determined:drawing is a phenomenological action that produces haptic drawings;it is an undecided process that originates unf.rmed drawings;it is a f.st action that results in small and multiplied drawings;it is a perceptual act that generates redrawn and remarked drawings;and f.nally,it is an action that seeks to remember to resume the creative process at another moment,which produces rudimentary conventional *** these bef.re any technological mediation will be an important pedagogical contribution that will allow f.ture architects not to alter the cognitive processes that generate the f.rst ideas in the initial moments of.the architectural project.

关键词： conception drawing Architectural thinking Graphic ideation concept creativity

The Importance of.Posterior Tibial Slope in TKR: Pre and Post-Operative Measurements in United States Osteoarthritic Patients

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Open Journal of.Orthopedics 2024年第8期14卷 374-379页

作者： f.ederick f. Buechel Sr f.ederick f. Buechel Jr Rutgers New Jersey Medical School Department of Orthopaedic Surgery Newark USA Lenox Hill Hospital Department of Orthopaedic Surgery New York USA

Background: Sagittal plane placement of.the tibial component in total knee replacement (TKR) has important implications f.r maximizing the range of.f.exion motion, allowing collateral ligaments to f.nction more normally, as well as providing ideal compressive loading on the tibial bone-prosthesis interf.ce. This study attempts to quantif. the normal posterior tibial slope (PTS) angle pre-operatively and post-operatively in osteoarthritic patients af.er using a conventional extramedullary tibial resection guide to assess its ef.ectiveness. Methods: f.rty-nine primary cementless total knee replacements in 34 osteoarthritic patients were measured radiographically pre-operatively and one year post-operatively to determine the PTS and its ef.ect on range of.motion. Lateral X-rays, using the anterior cortical line of.the tibia, were employed f.r all measurements. Results: Pre-operative PTS measured 11.83˚ (range 5˚ - 18˚), while post-operative PTS of.implanted tibial components measured 11.30o (range 4˚ - 18˚). The pre-operative range of.motion of.112˚ (range 30˚ to 135˚) was improved to 119˚ (range 90˚ to 135˚) post-operatively af.er 1 year. conclusions: Anterior tibial shaf. ref.rencing using a conventional extramedullary tibial resection guide provides an easy and convenient method f.r reproducing the anatomical PTS during TKR. This methodology provided improvement in average range of.motion f.om 112˚ pre-operatively to 119˚ post-operatively at one year.

关键词： Posterior Tibial Slope Posterior Tibial Inclination Extramedullary Tibial Resection Guide Total Knee Alignment

comparisons of.oxbow lake f.sh assemblages in relation to bigheaded carp establishment in the lower White River, Arkansas

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Ecological Processes 2024年第1期13卷 188-205页

作者： Michael A.Eggleton cody J.Salzmann Joseph E.Kaiser Shannon c.f.Smith Department of.Aquaculture and f.sheries University of Arkansas at Pine Bluff Arkansas Game and f.sh commission Virginia Institute of.Marine Science

Background Since the late 1990s, bigheaded carps(largely silver carp [Hypophthalmichthys molitrix] but also bighead carp [H. nobilis]) have established throughout the lower Mississippi River basin. Using previously studied oxbow lakes in the lower White River basin, Arkansas, we compared current(2017, “post-carp” establishment) f.sh assemblages to historical(2002, “pre-carp” establishment) f.sh assemblages. f.sh assemblages were comprehensively assessed using multiple gears, including boat electrof.shing, mini-f.ke nets, and experimental small-mesh gill *** T-tests suggested that f.sh assemblage indices of.richness, diversity, evenness, and dominance were of.en greater(P carp period as ref.ected by boat electrof.shing and experimental gill nets. However, all indices were generally similar(P > 0.05) between the pre-carp and post-carp period with f.sh assemblages depicted using mini-f.ke nets. Nonmetric multidimensional scaling analyses indicated that f.sh assemblages dif.ered structurally between pre-carp and post-carp periods. Assemblage dif.erences were linked to both small and large abundance changes f.r more than 20 species. Abundances of.gizzard shad(Dorosoma cepedianum), emerald shiner(Notropis atherinoides), pugnose minnow(Opsopoeodus emiliae), crappies(Pomoxis spp.), bluegill(Lepomis macrochirus), orangespotted sunf.sh(L. humilis), and yellow bass(Morone mississippiensis) declined between the pre-carp and postcarp periods. conversely, abundances of.weed shiner(N. texanus), pallid shiner(Hybopsis amnis), longear sunf.sh(L. megalotis), buf.alof.shes(Ictiobus spp.), and gars(Lepisosteus spp.) generally increased during the same *** Although not possible to conclude assemblage shif.s were entirely related to bigheaded carps due to the absence of.an appropriate ref.rence system where carps did not establish, the wide establishment of.these carps is one of.the most pervasive changes to have occurred in the lower White

关键词： Bigheaded carp Silver carp Aquatic nuisance species f.sh assemblage Oxbow lake Large river

Thermoluminescence characterization of.natural and synthetic irradiated ce-monazites

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Journal of.Rare Earths 2024年第4期42卷 643-650页

作者： V.correcher c.Boronat J.Garcia-Guinea J.f.Benavente T.Rivera-Montalvo cIEMAT Av.Complutense 4028040MadridSpain MNcN-cSIc J.Gutierrez Abascal 228006MadridSpain Instituto Politécnico Nacional CICATA-IPNAv.Legaria 694Mexico City11500Mexico

The thermoluminescence(TL)emission of.synthetic and natural ce-monazites was characterized here to determine the potential application in the identif.cation of.microscopic def.cts f.om a qualitative point of.view trying to link each TL peak to a chemical-physical *** kinetic parameters that lead the luminescence processes were calculated by means of.variable heating rate and computing glow curve deconvolution methods and allow identif.ing three groups of.components at~90,130 and 290℃(f.r the mineral sample)and~90,170,220,270 and 320℃(f.r the synthetic cePO_(4):Nd_(0.20),La_(0.25)).The main dif.erences appreciated in these complex TL curves are mainly due to(i)the content of.impurities(natural sample contains lanthanides as well as U 0.60%and Th 5.22%)and(ii)the degree of.crystallinity of.the samples which is directly related to the type of.impurities(synthetic monazite relies only on Nd and La).The behavior of.the dose response in the range of.1-8 Gy is similar f.r both samples;the TL intensity increases linearly as the dose increases without changes in the position of.the maxima,denoting f.rst-order kinetic luminescence *** peak could be mostly associated with structural def.cts(i.e.,phase transitions),chemical reactions(i.e.,ce3+?ce4+redox reaction,dehydration or dehydroxylation processes)or intrinsic def.cts(i.e.,f.enkel def.cts,ODcs or NBOHcs).

关键词： Thermoluminescence Kineticparameters Phosphate ce-monazite Def.cts Rare earths

Evaluating transient behaviour of.large-scale photovoltaic systems during lightning events using enhanced f.nite dif.erence time domain method with variable cell size approach

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HIGH VOLTAGE 2024年第3期9卷 636-647页

作者： Hetita, Ibrahim Mansour, Diaa-Eldin A. Han, Yang Yang, Ping Wang, congling Darwish, Mohamed M. f. Lehtonen, Matti Zalhaf. Amr S. Univ Elect Sci & Technol china UESTc Sch Mech & Elect Engn Chengdu Peoples R China Helwan Univ Fac Engn Elect Power & Machines Engn Dept Cairo Egypt Tanta Univ Fac Engn Elect Power & Machines Engn Dept Tanta Egypt Egypt Japan Univ Sci & Technol Fac Engn Dept Elect Power Engn Alexandria Egypt Benha Univ Fac Engn Shoubra Dept Elect Engn Cairo Egypt Aalto Univ Sch Elect Engn Dept Elect Engn & Automation Espoo Finland GMc Dept Med Srinagar Jammu And Kashm India

Photovoltaic (PV) arrays are usually installed in open areas; hence, they are vulnerable to lightning strikes that can result in cell degradation, complete damage, service disruption, and increased maintenance costs. As a result, it is imperative to develop an ef.ective and ef.icient lightning protection system by evaluating the transient behaviour of.PV arrays during lightning events. The aim is to evaluate the transient analysis of.large-scale PV systems when subjected to lightning strikes using the f.nite dif.erence time domain (f.TD) technique. Transient overvoltages are calculated at various points within the mounting system. To optimise the f.TD method's execution time and make it more suitable f.r less powerf.l hardware, a variable cell size approach is employed. Specif.cally, larger cell dimensions are used in the earthing system and smaller cell dimensions are used in the mounting system. The f.TD method is utilised to calculate the temporal variation of.transient overvoltages f.r large-scale PV systems under dif.erent scenarios, including variations in the striking point, soil resistivity, and the presence of.a metal f.ame. Simulation results indicate that the highest transient overvoltages occur at the striking point, and these values increase with the presence of.a PV metal f.ame as well as with higher soil resistivity. f.rthermore, a comparison is perf.rmed between the overvoltage results obtained f.om the f.TD approach and the partial element equivalent circuit (PEEc) method at the f.ur corner points of.the mounting systems to demonstrate the superior accuracy of.the f.TD method. Besides, a laboratory experiment is conducted on a small-scale PV system to validate the simulation results. The calculated overvoltages obtained f.om the f.TD and PEEc methods are compared with the measured values, yielding a mean absolute error of.5% and 11% f.r the f.TD and PEEc methods, respectively, thereby conf.rming the accuracy of.the f.TD simulation model.

关键词： f.TD METHOD MODEL