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Effects 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 Safety and Health(NIOSH) PittsburghPAUSA

Control of dust in underground coal mines is critical for mitigating both safety and health *** decades,the National Institute of Occupational Safety and Health(NIOSH)has led research to evaluate the effectiveness 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 focus of such studies,this is a growing area of *** preserved filter samples from three previous NIOSH studies,the current work aims to explore the effect of two different scrubbers(one wet and one dry)and a roof bolter CAC on respirable dust composition and particle size *** this,the preserved filter samples were analyzed by thermogravimetric analysis and/or scanning electron microscopy with energy dispersive *** indicate that dust composition was not appreciably affected by either scrubber or the ***,the wet scrubber and CAC appeared to decrease the overall particle size *** an effect of the dry scrubber was not consistently observed,but this is probably related to the particular sampling location downstream of the scrubber which allowed for significant mixing of the scrubber exhaust and other return *** from the insights gained with respect to the three specific dust control case studies revisited here,this work demonstrates the value of preserved dust samples for follow-up investigation more broadly.

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

Converting TREx-RGB green-channel data to 557.7 nm auroral intensity:Methodology and initial results

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Earth and Planetary Physics 2024年第1期8卷 258-274页

作者： Jun Liang D.M.Gillies E.Spanswick E.f.Donovan University of Calgary CalgaryT2N 1N4Canada

The recently deployed Transition Region Explorer(TREx)-RGB(red-green-blue)all-sky imager(ASI)is designed to capture“true color”images of the aurora and *** the 557.7 nm green line is usually the brightest emission line in visible auroras,the green channel of a TREx-RGB camera is usually dominated by the 557.7 nm *** this rationale,the TREx mission does not include a specific 557.7 nm imager and is designed to use the RGB green-channel data as a proxy for the 557.7 nm *** this study,we present an initial effort to establish the conversion ratio or formula linking the RGB green-channel data to the absolute intensity of 557.7 nm auroras,which is crucial for quantitative uses of the RGB *** illustrate two approaches:(1)through a comparison with the collocated measurement of green-line auroras from the TREx spectrograph,and(2)through a comparison with the modeled green-line intensity according to realistic electron precipitation flux measurements from low-Earth-orbit satellites,with the aid of an auroral transport *** demonstrate the procedures and provide initial results for the TREx-RGB ASIs at the Rabbit Lake and Lucky Lake *** RGB response is found to be *** conversion ratios or formulas between RGB green-channel data and the green-line auroral intensity are given and can be applied immediately by TREx-RGB data *** methodology established in this study will also be applicable to the upcoming SMILE ASI mission,which will adopt a similar RGB camera system in its deployment.

关键词： TREx RGB green-line aurora auroral transport model

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 effects 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 significantly reduces the stress generation by efficiently accommodating the volume change associated with the lithium diffusion,and the coating layer plays roles both as a cushion against the volume change and a channel for the lithium transport,promoting the lithium distribution across the secondary particles more ***,the lower stiffness,higher ionic conductivity,and larger thickness of the coating layer improve the stress *** paper provides a mathematical framework for calculating the chemo-mechanical responses of anisotropic electrode materials and fundamental insights into how the coating of NMC active particles mitigates stress levels.

关键词： lithium-ion battery(LIB) polycrystalline particle coating finite element simulation Ni-rich LiNixMnyCo_(z)O_(2)(x>0.8)(NMC)

Asymmetric reversible structural switching of a diene coordination polymer promoted by UV-visible light

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Science China Chemistry 2024年第2期67卷 536-541页

作者： Yong Wang Qiaoqiao Zhang Yong-Yong Cao Qi Liu Brendan f.Abrahams Jian-Ping Lang College of Chemistry Chemical Engineering and MaterialsSoochow UniversitySuzhou215123China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032China College of Biological Chemical Science and EngineeringJiaxing UniversityJiaxing314001China School of Chemistry University of MelbourneVictoria3010Australia

In natural and artificial systems,reversible reactions are commonly asymmetric with respect to the time scale and nature of the stimuli which drive the forward and backward *** applications for which switching behavior is required,it is desirable that the reversible reaction goes as close to symmetric as possible;however,such systems are ***,we report an example of ultraviolet(UV)-visible light-regulated asymmetric reversible structural switching involving a diene-based coordination polymer,CP1 and its monocyclobutane product,*** is possible to cycle at least ten times through a forward [2+2] photocycloaddition reaction and the reverse,photocleavage reaction.A single cycle can be completed within a few *** transformation is accompanied by fast and distinct fluorescence changes,arising from optimisation of the reaction *** functional theory calculations allow rationalisation of the asymmetric reversible transformation between CP1 and CP1a rather than between CP1 and its dicyclobutane product *** work provides a clear illustration of reversible structural switching which approaches symmetric behaviour with respect to reaction rate and *** insights gained from this work also assist in the design of fast,reversible switching materials.

关键词： asymmetrical reversible structural switching coordination polymer photocycloaddition UV-visible light-controlled fluorescence switching

Omics-based biomarkers as useful tools in metabolic dysfunctionassociated steatotic liver disease clinical practice:How far are we?

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World Journal of Gastroenterology 2024年第14期30卷 1982-1989页

作者： Julieta Trinks María f Mascardi Adrián Gadano Sebastián Marciano Instituto de Medicina Traslacional e Ingeniería Biomédica-Consejo Nacional de Investigaciones Científicas y Técnicas-Instituto Universitario del Hospital Italiano-Hospital Italiano de Buenos Aires Ciudad Autónoma de Buenos Aires C1199ACLArgentina Consejo Nacional de Investigaciones Científicas y Técnicas Ciudad Autónoma de Buenos Aires C1425FQBArgentina Liver Unit Hospital Italiano de Buenos AiresCiudad Autónoma de Buenos Aires C1199DFArgentina Department of Research Hospital Italiano de Buenos AiresCiudad Autónoma de Buenos Aires C1199DFArgentina

Unmet needs exist in metabolic dysfunction-associated steatotic liver disease(MASLD)risk *** ability to identify patients with MASLD with advanced fibrosis and at higher risk for adverse outcomes is still *** novel biomarkers could represent a meaningful improvement to current risk *** this aim,omics technologies have revolutionized the process of MASLD biomarker discovery over the past *** the research in this field is thriving,much of the publication has been haphazard,often using single-omics data and specimen sets of convenience,with many identified candidate biomarkers but lacking clinical validation and *** we incorporate these biomarkers to direct patients’management,it should be considered that the roadmap for translating a newly discovered omics-based signature to an actual,analytically valid test useful in MASLD clinical practice is rigorous and,therefore,not easily *** article presents an overview of this area’s current state,the conceivable opportunities and challenges of omics-based laboratory diagnostics,and a roadmap for improving MASLD biomarker research.

关键词： Metabolic dysfunction-associated steatotic liver disease Non-alcoholic steatohepatitis Biomarker Risk stratification Omics

A New Method for Deriving High-Vertical-Resolution Wind Vector Data from the L-Band Radar Sounding System in China

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Advances in Atmospheric Sciences 2024年第11期41卷 2192-2202页

作者： Yuan f. Zhou Z. Liao J. National Meteorological Information Center China Meteorological Administration Beijing 100081 China

High-vertical-resolution radiosonde wind data are highly valuable for describing the dynamics of the meso- and microscale atmosphere. However, the current algorithm used in China’s L-band radar sounding system for calculating high-vertical-resolution wind vectors excessively smooths the data, resulting in significant underestimation of the calculated kinetic energy of gravity waves compared to similar products from other countries, which greatly limits the effective utilization of the data. To address this issue, this study proposes a novel method to calculate high-vertical-resolution wind vectors that utilizes the elevation angle, azimuth angle, and slant range from L-band radar. In order to obtain wind data with a stable quality, a two-step automatic quality control procedure, including the RMSE-f (root-mean-square error f) test and elemental consistency test are first applied to the slant range data, to eliminate continuous erroneous data caused by unstable signals or radar malfunctions. Then, a wind calculation scheme based on a sliding second-order polynomial fitting is utilized to derive the high-vertical-resolution radiosonde wind vectors. The evaluation results demonstrate that the wind data obtained through the proposed method show a high level of consistency with the high-resolution wind data observed using the Vaisala Global Positioning System and the data observed by the new Beidou Navigation Sounding System. The calculation of the kinetic energy of gravity waves in the recalculated wind data also reaches a level comparable to the Vaisala observations. © Institute of Atmospheric Physics/Chinese Academy of Sciences, and Science Press 2024.

关键词： high-vertical-resolution radiosonde wind vectors L-band radar sounding system polynomial fitting quality control upper air

Threshold-Based Software-Defined Networking(SDN)Solution for Healthcare Systems against Intrusion Attacks

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1469-1483页

作者： Laila M.Halman Mohammed J.f.Alenazi Department of Computer Engineering College of Computer ScienceKing Saud UniversityRiyadh11451Saudi Arabia

The healthcare sector holds valuable and sensitive *** amount of this data and the need to handle,exchange,and protect it,has been increasing at a fast *** to their nature,software-defined networks(SDNs)are widely used in healthcare systems,as they ensure effective resource utilization,safety,great network management,and *** this sector,due to the value of thedata,SDNs faceamajor challengeposed byawide range of attacks,such as distributed denial of service(DDoS)and probe *** attacks reduce network performance,causing the degradation of different key performance indicators(KPIs)or,in the worst cases,a network failure which can threaten human *** can be significant,especially with the current expansion of portable healthcare that supports mobile and wireless devices for what is called mobile health,or *** this study,we examine the effectiveness of using SDNs for defense against DDoS,as well as their effects on different network KPIs under various *** propose a threshold-based DDoS classifier(TBDC)technique to classify DDoS attacks in healthcare SDNs,aiming to block traffic considered a hazard in the form of a DDoS *** then evaluate the accuracy and performance of the proposed TBDC *** technique shows outstanding performance,increasing the mean throughput by 190.3%,reducing the mean delay by 95%,and reducing packet loss by 99.7%relative to normal,with DDoS attack traffic.

关键词： Network resilience network management attack prediction software defined networking(SDN) distributed denial of service(DDoS) healthcare

Adsorption of pharmaceutical pollutants on ZnCl_(2)-activated biochar from corn cob:Efficiency,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 for the envi-ronment and human health,thus it is necessary to study methodologies that allow the efficient removal of these *** this work,corn cob-derived biochar was obtained by ZnCl_(2)-activation,and subsequent carbonization at 700℃.The effect 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 for ACE and 175.86 mg/g for *** adsorption kinetics and adsorption isotherm of ACE corresponded to the pseudo-second order and Langmuir model,***,pseudo-first-order kinetics and the freundlich isotherm model were well-fitted to AMX *** ACE and AMX co-adsorption had a synergistic effect on AMX but an antagonistic effect on ACE removal,achieving a maximum adsorption capacity of 193.51 and 184.58 mg/g,*** the other hand,fixed-bed column experiments showed that the adsorption capacity depends on the influent concentration,and the breakthrough curve fits the Thomas and Yoon-Nelson *** mechanism adsorption studies showed that surface inter-actions(hydrogen bonding formation and n-𝜋interactions)are the main driving forces for the adsorption process,and pore filling is the rate-limiting *** this way,the prepared biochar exhibits a high potential for the adsorption of pharmaceutical compounds from water.

关键词： Biochar Adsorption Acetaminophen Amoxicillin Wastewater treatment

Effects of synthesis parameters on the performance of crosslinked Co-polymers with clays for conformance control

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Petroleum Research 2024年第1期9卷 98-108页

作者： A.A.Roslan N.A.A.Aziz N.f.A.Deraman I.Dzulkarnain Petroleum Engineering Department Centre of Research Enhanced Oil Recovery(COREOR)Universiti Teknologi PETRONASSeri IskandarPerakMalaysia Chemical Engineering Department Centre of Research Enhanced Oil Recovery(COREOR)Universiti Teknologi PETRONASSeri IskandarPerakMalaysia

Conformance control or water shut-off is a technique used to improve oil *** conformance control,polymers block high permeability water areas and redistribute water drive toward unswept oil *** this study,co-polymers(denoted ATP-PGV/AM-co-AMPS)were synthesized using acrylamide(AM)and 2-acrylamide-2-methylpropane sulfonic acid(AMPS)as the monomers,polyethylene glycol(PEG)-200 and methylenebisacrylamide(MBA)as the crosslinkers,attapulgite(ATP)and bentonite(PGV)as the clay types,and ammonium persulfate(APS)as the initiator,in addition to paraffin oil and *** were synthesized using inverse emulsion polymerization with different concentrations of monomers,crosslinkers,and clays,and they were characterized using fourier-transform infrared(fTIR)spectroscopy and scanning electron microscopy(SEM)with energy dispersive X-ray spectroscopy(EDX).fTIR spectra of the samples confirmed the existence of sulfonate and hydroxyl groups,which are important for polymer ***-EDX images indicated that the morphology and elemental composition were different before and after swelling,confirming the occurrence of ***,samples were placed in sodium chloride solution(20,000 ppm)for 7 days to evaluate swelling at both room temperature and 90°*** analysis(TGA)and differential scanning calorimetry(DSC)were used to determine the thermal characteristics of the ***,rheological measurements were used to assess the deformation and rheological behavior of the *** results showed that after 1 day,good swelling without loss of mechanical strength was achieved with the composite synthesized using 10%AM,15%AMPS,6%PGV,and 10%ATP.

关键词： Polymer Clay Water shut-off Conformance Swelling