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Friction 2024年第9期12卷 2126-2138页

作者： Ainhoa GUiNEA Andrea AGiNAGALDE Wilson TATO iñigo LLAVORi Pablo GARCiA Leire ARRAiAGO Alaitz ZABALA Mechanical and industrial Production Department Mondragon UnibertsitateaMondragon 20500Spain Orona EiC Orona IdeoHernani 20120Spain

The coefficient of friction(CoF)between the deflection pulley and rope in a lift strongly affects the life span of the *** surface roughness is a key factor affecting the metallic pulley–rope CoF,its effect on polymeric pulleys is *** present study analyses the effect of roughness and working conditions on cast polyamide 6(PA6G)deflection pulley–thermoplastic polyurethane(TPU)-coated rope *** statistical analysis revealed that the effect of surface roughness on the CoF for low-load tests was *** present study contributes significantly to parameter selection in deflection pulley machining to minimise friction between the pulley and rope.

关键词： polymer-on-polymer friction roughness dry sliding

A plant growth chamber system equipped with aerosol generators for studying aerosol-vegetation interactions

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Particuology 2024年第2期85卷 122-132页

作者： Masao Gen Seiji ikawa Masahiro Yamaguchi Fong Zyin Lim Takeshi izuta i.Wuled Lenggoro Graduate School of Bio-Applications and Systems Engineering Tokyo University of Agriculture and TechnologyKoganeiTokyo184-8588Japan institute of Multidisciplinary Research for Advanced Materials Tohoku UniversitySendai980-8577Japan Faculty of Agriculture Tokyo University of Agriculture and TechnologyFuchuTokyo183-8509Japan Graduate School of Fisheries and Environmental Sciences Nagasaki UniversityNagasaki852-8521Japan institute of Agriculture Tokyo University of Agriculture and TechnologyFuchuTokyo183-8509 Japan Department of Applied Physics and Chemical Engineering Tokyo University of Agriculture and TechnologyKoganeiTokyo184-8588Japan institute of Global innovation Research Tokyo University of Agriculture and TechnologyFuchuTokyo183-8509Japan

Understanding aerosol-vegetation interactions is vital in ***,the interactions remain elusive partly due to the lack of suitable plant growth chamber ***,deposition of submicron particles on leaf surfaces is challenging due to its low deposition velocities compared to larger *** this work,we present a plant-growth chamber that was used to study the effect of sub-micron black carbon(BC)particles on the growth and photosynthesis of *** chamber system simultaneously enables the growth of multiple plants in pots and the deposition of submicron particles onto *** spraying methods assisted by ultrasonic and electrostatic forces were employed as aerosol generators to realize the particle *** flow regime inside the chamber was numeri-cally calculated to predict the transportation of aerosol particles,suggesting the optimal operating conditions of the *** gas-phase particle size distribution measurements showed that gener-ated BC particles were suspended in submicron diameter *** aerosol generators were examined in the chamber using three conductor and insulator substrates as a model of plant *** observations and spectroscopic analysis ascertained that submicron BC particles generated from our generators were deposited on all substrate *** the developed chamber system,systematic studies can be performed to advance the fundamental understanding of aerosol-vegetation interactions.

关键词： Aerosol Exposure chamber Spray drying Black carbon

Design,simulation,and testing of a tunable MEMS multi-threshold inertial switch

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Microsystems & Nanoengineering 2024年第2期10卷 37-46页

作者： Qiu Xu Rodrigo T.Rocha Yousef Algoos Eric Feron Mohammad i.Younis Faculty of Electronic information Engineering Huaiyin Institute of TechnologyHuai’an223003PR China Computer Electrical and Mathematical Science and Engineering DivisionKing Abdullah University of Science and TechnologyThuwal23955-6900Saudi Arabia Piezoelectric Microsystem Technologies Silicon Austria LabsVillach9524Austria Physical Sciences and Engineering Division King Abdullah University of Science and TechnologyThuwal23955Saudi Arabia Mechanical Engineering Department State University of New YorkBinghamtonNY13902USA

This paper presents a tunable multi-threshold micro-electromechanical inertial switch with adjustable threshold *** demonstrated device combines the advantages of accelerometers in providing quantitative acceleration measurements and g-threshold switches in saving power when in the inactive state upon experiencing acceleration below the *** designed proof-of-concept device with two thresholds consists of a cantilever microbeam and two stationary electrodes placed at different positions in the sensing *** adjustable threshold capability and the effect of the shock duration on the threshold acceleration are analytically investigated using a nonlinear beam *** are shown for the relationships among the applied bias voltage,the duration of shock impact,and the tunable *** fabricated prototypes are tested using a shock-table *** analytical results agree with the experimental *** designed device concept is very promising for the classification of the shock and impact loads in transportation and healthcare applications.

关键词： tunable acceleration testing

improving antioxidant activities of water-soluble lignin-carbohydrate complex isolated from wheat stalk through prolonging ball-milling pretreatment and homogeneous extraction

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Journal of Bioresources and Bioproducts 2024年第1期9卷 113-125页

作者： Di Xie Zhulan Liu Yunfeng Cao Sheng-i Yang Chen Su Mi Li Jiangsu Co-innovation Center for Efficient Processing and Utilization of Forest Products Nanjing Forestry UniversityNanjing 210037China international innovation Center for Forest Chemicals and Materials Nanjing Forestry UniversityNanjing 210037China Center for Renewable Carbon School of Natural ResourcesUniversity of TennesseeKnoxvilleTN 37996USA Shandong Huatai Paper Co. Ltd.Dongying 257000China School of Natural Resources University of TennesseeKnoxvilleTN 37996USA Key Lab of Biomass Energy and Material Institute of Chemical Industry of Forest ProductsChinese Academy of ForestryJiangsu ProvinceNanjing 210042China

Water-soluble lignin-carbohydrate complex(LCC)rich in polysaccharides exhibits benign in vitro antioxidant activities and distinguishes high biocompatibility from lignin-rich LCC and ***,the antioxidant activity of water-soluble LCCs remains to be improved and its structure-antioxidant relationship is still ***,structurally diversified water-soluble LCCs were isolated under different ball-milling pretreatment durations(4,6,8 h),extraction pathways(ho-mogeneous and heterogeneous),and isolation routines(water extracts and residues after water extraction).Their structures were characterized by wet chemistry,chromatography and *** activities were evaluated by ferric reducing antioxidant power and 1,1-diphenyl-2-picrylhydrazyl radicals scavenging rate(RDPPH).Results show that altering ball-milling duration and isolation procedures cause varied structures and antioxidant activities of the water-soluble ***,prolonging ball-milling duration to 8 hours and homogeneous extrac-tion can enhance their antioxidant activity through releasing more phenolic structures and pro-moting the extraction of high-molecular-weight LCCs via reducing mass-transfer resistance,*** a result,the RDPPH of water-soluble LCCs reaches up to 97.35%,which is associated with the arabinan content with statistical significance(Pis study provides new insights into the structure-antioxidation relationship of herbaceous LCC as potential antioxidants.

关键词： LCC Homogeneous extraction Ball-milling Structure-antioxidation relationship Wheat straw

Selection of shaped charges parameters for producing aluminum particles with velocities in the range of 2.5-16 km/s

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Defence Technology（防务技术） 2024年第8期38卷 126-135页

作者： vladi.i. i.Kolpakov Sergey V.Fedorov Ekaterina P.Vinogradova irina A.Bolotina Bauman Moscow State Technical University Moscow 105005Russia

Testing rocket and space technology objects in ground conditions for resistance to the impact of meteoroids and fragments of space debris can be carried out using shaped charges. To substantiate the design parameters of shaped charges that ensure the formation of aluminum particles in a wide velocity range(from 2.5 to 16 km/s), numerical modeling of the formation process was carried out within the framework of a two-dimensional axisymmetric problem of continuum mechanics using three different computing codes to increase the reliability of the results. The calculations consider shaped charges with a diameter of 20-100 mm with aluminum liners of various shapes. it is shown that the formation of particles with velocities close to the lower limit of the considered range is ensured by gently sloping segmental liners of degressive thickness. To form higher-velocity particles with velocities over 5 km/s, it is proposed to use combined liners, the jet-forming part of which has the shape of a hemisphere of constant thickness or the shape of a semi-ellipsoid or semi-superellipsoid of rotation of degressive thickness.

关键词： Space debris Meteoric impact Explosion Shaped charge High-velocity aluminum element Segmental liner Combined liner Numerical simulation

Beneficial use of mussel shell as a bioadditive for TPU green composites by the valorization of an aqueous waste

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Waste Disposal and Sustainable Energy 2024年第1期6卷 123-137页

作者： SedefŞişmanoğlu Yasin Kanbur Carmen-Mihaela Popescu Diana Kindzera Ümit Tayfun Department of Chemistry Karabuk University78050KarabukTurkey Petru Poni institute of Macromolecular Chemistry of the Romanian Academy 700487IasiRomania Department of Chemical Engineering Lviv Polytechnic National UniversityLviv79013Ukraine Department of Basic Sciences Bartin University74110BartinTurkey

Scientific studies have focused on environmentally friendly solutions as effective as the reuse of crop products owing to plastic-waste problems in recent *** issue is the main driving force for upcoming academic research attempts in waste valorization-related ***,we integrated an aqua-waste,mussel shell(MS),as a bioadditive form into green thermoplastic polyurethane(TPU)green *** of the MS surface was performed to achieve strong adhesion between composite *** surface functionalities of MS powders were evaluated via infrared spectroscopy and scanning electron microscopy(SEM)*** samples were prepared by melt-compounding followed by injection molding *** was confirmed by morphological analysis that relatively better adhesion between the phases was achieved for composites involving surface-modified MS compared to unmodified *** strength and Young’s modulus of surface-modified MS-filled composites were found to be higher than those of unmodified MS,whereas the elongation at break shifted to lower values with MS *** shore hardness of TPU was remarkably improved after being incorporated with silane-treated MS(AS-MS).Stearic acid-treated MS(ST-MS)additions resulted in an enhancement in the thermal stability of the ***-mechanical analysis showed that the storage moduli of composites were higher than those of unfilled ***-MS additions led to an increase in the characteristic glass transition temperature of *** flow index(MFi)of neat TPU was highly improved after MS loading regardless of modification *** to the wear test,surface modification of MS displayed a positive effect on the wear resistance of *** the water absorption data of the composites were evaluated,the TPU/AS-MS composite yielded the lowest water *** silane layer on MS inclusion promoted water repellency of composites due to the hydrophobicity of *** results of the biodegradation

关键词： Aqua-waste Polyurethane Mussel shell Green composites Sustainability Waste valorization

Are school uniforms associated with gender inequalities in physical activity? A pooled analysis of population-level data from 135 countries/regions

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Journal of Sport and Health Science 2024年第4期13卷 590-598页

作者： Mairead Ryan Luiza i.C.Ricardo Nicole Nathan Riikka Hofmann Esther van Sluijs Medical Research Council Epidemiology Unit University of CambridgeCambridge CB20QQUK Faculty of Education University of CambridgeCambridge CB28PQUK Hunter New England Population Health WallsendNSW 2287Australia School of Medicine and Public Health College of HealthMedicine and WellbeingUniversity of NewcastleCallaghanNSW 2308Australia Hunter Medical Research institute New Lambton HeightsNSW 2305Australia National Centre of implementation Science University of NewcastleCallaghanNSW 2308Australia

Purpose:it is aimed to assess whether school uniforms are associated with population-level gender inequalities in physical activity,and whether associations differ by school level,country/region income,and assessment ***:An ecological study design was *** collected data about global uniform practices using an online *** searched for country/region-level estimates of school-aged youth meeting physical activity guidelines from international surveillance *** selection was conducted in duplicate using a systematic process,and a random sample of all data was checked to ensure extraction and pooling processes were *** calculated absolute and relative gender inequalities in physical activity for each *** regression examined associations between country/region-level uniform practices(binary yes/no exposure variable) and country/region-level gender inequalities in physical activity guideline compliance(absolute and relative inequalities).We investigated moderation by school level,stratified analyses by income group,and repeated primary analyses using device-measured ***:Pooling data from 135 countries/regions(n=1,089,852),we found no association between population-level uniform practices and gender inequalities in physical activity across all ages(absolute:β=-0.2;95% confidence interval(95%Ci):-1.7 to 1.3,p=0.74;relative:β=0.1;95%Ci:-0.1 to 0.2,p=0.51).Subgroup analysis suggested a positive association in primary school settings(absolute:β=4.3;95%Ci:-0.0 to 8.6,p=0.05).Among high-income countries,absolute inequalities were significantly greater in countries/regions with uniform practices(N=37) compared to those without(N=48)(9.1(SD=3.6) vs.7.8 percentage points(SD=4.3)).Repeating analyses using device-measured data(n=32,130;N=24) did not alter our primary *** initial descriptive statistics,we found that in countries/regions where a maj ority of schools(>50%) reportedly use uniforms,there was lower compli

关键词： School policy Clothing Child Adolescent Accelerometer

Slope stability of reclaimed coal mines through a new water filling index

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 828-839页

作者： Antonios Mikroutsikos Alexandros i.Theocharis Nikolaos C.Koukouzas ioannis E.Zevgolis Chemical Process&Energy Resources institute Centre for Research&Technology HellasAthensGreece School of Mining and Metallurgical Engineering National Technical University of AthensAthensGreece

A common reclamation practice for closed coal surface mines is filling them with water to form pit *** creation and sustainability of these lakes are significantly affected by the stability of the corresponding *** present study provides a general framework for analyzing the water filling’s effect on slope stability based on a new water filling index,which can indirectly consider the factors affecting the process and efficiently quantify the filling speed’s *** assumptions of the proposed approach are thoroughly discussed,and the range of the water filling index is ***,the safety factor is calculated using the finite element method with the shear strength reduction technique during the filling process for various conditions(soil properties,slope geometry,hydraulic conditions,and water filling speed).Results are presented as normalized stability charts for practical *** the water filling,the stability gradually decreases until the reservoir reaches a critical level of 10%e40%of the total height;it then increases to even more stable conditions than the initial ***,the present analysis allows for the preliminary stability evaluation of a coal mine during the formation of a pit lake and the appropriate quantification of the water filling’s effect.

关键词： Post-coal era Open-pit flooding Stability charts Critical level

Patient-centered care in diabetes care-concepts,relationships and practice

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World Journal of Diabetes 2024年第7期15卷 1417-1429页

作者： Tsung-Tai Chen Wei-Chih Su Mei-i Liu Department of Public Health College of MedicineFu Jen Catholic UniversityNew Taipei 24205Taiwan Department of Gastroenterology Taipei Tzu-Chi HospitalNew Taipei 23142Taiwan Department of Pediatric Endocrinology Mackay Children's HospitalTaipei 10449Taiwan

We still do not have comprehensive knowledge of which framework of patientcentered care(PCC)is appropriate for diabetes care,which elements of PCC are evidence-based,and the mechanism by which PCC elements are associated with outcomes through *** this review,we elaborate on these *** found that for diabetes care,PCC elements such as autonomy support(patient individuality),cooperation and collaboration(system-level approach),communication and education(behavior change techniques),emotional support(biopsychosocial approach),and family/other involvement and support are critically *** of these factors are directly associated with different patient outcomes and indirectly associated with outcomes through patient *** present the practical implications of these PCC elements.

关键词： Diabetes mellitus Patient-centered care Autonomy support Patient activation Patient adherence

Constrained re-calibration of two-equation Reynolds-averaged Navier–Stokes models

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Theoretical & Applied Mechanics Letters 2024年第2期14卷 82-89页

作者： Yuanwei Bin Xiaohan Hu Jiaqi Li Samuel J.Grauer Xiang i.A.Yang Department of Mechanical Engineering Pennsylvania State UniversityUniversity ParkPA 16802USA State Key Laboratory for Turbulence and Complex Systems Peking UniversityBeijing 100871China College of Engineering Peking UniversityBeijing 100871China

Machine-learned augmentations to turbulence models can be advantageous for flows within the training dataset but can often cause harm *** lack of generalizability arises because the constants(as well as the functions)in a Reynolds-averaged Navier–Stokes(RANS)model are coupled,and un-constrained re-calibration of these constants(and functions)can disrupt the calibrations of the baseline model,the preservation of which is critical to the model's *** safeguard the behaviors of the baseline model beyond the training dataset,machine learning must be constrained such that basic calibrations like the law of the wall are kept *** letter aims to identify such constraints in two-equation RANS models so that future machine learning work can be performed without violating these *** demonstrate that the identified constraints are not ***,they help preserve the generalizability of the baseline model.

关键词： Machine learning Turbulence modeling Reynolds-averaged Navier-Stokes