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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

Fault Location Method for Overhead Feeders with Distributed generation Units Based on Direct Load Flow Approach

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1135-1146页

作者： Charalampos g.Arsoniadis Vassilis C.Nikolaidis Department of Electrical and Computer Engineering Democritus University of ThraceXanthi 67100Greece

This paper proposes a novel fault location method for overhead feeders,which is based on the direct load flow *** method is developed in the phase domain to effec-tively deal with unbalanced network conditions,while it can al-so handle any type of distributed generation(Dg)units without requiring equivalent *** utilizing the line series parame-ters and synchronized or unsynchronized voltage and current phasor measurements taken from the sources,the method reli-ably identifies the most probable faulty *** the aid of an index,the exact faulty section among the multiple candi-dates is *** simulation studies for the iEEE 123-bus test feeder demonstrate that the proposed method accu-rately estimates the fault position under numerous short-circuit conditions with varying pre-fault system loading conditions,fault resistances,and measurement *** proposed meth-od is promising for practical applications due to the limited number of required measurement devices as well as the short computation time.

关键词： Fault location distribution system direct load flow distributed generation

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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

Comparative measurement of CO_(2),CH_(4)and CO at two traffic interjunctions having inflated vehicular flow in Delhi

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Journal of Environmental Sciences 2024年第7期141卷 314-329页

作者： Komal Daya Soni Khem Singh Shankar g.Aggarwal CSiR-National Physical Laboratory Dr.K.S.Krishnan MargNew Delhi 110012India Academy of Scientific&innovative Research(AcSiR) Ghaziabad 201002India

Vehicular emissions are considered one of the major anthropogenic sources of greenhouse gases and poor air quality in metropolitan *** study aims to see the correlation of CO_(2),CH_(4),and CO through monitoring over a period from December 2020 to October 2021 covering three seasons’winter,summer,and monsoon at two different traffic locations of Delhi having different traffic volumes,road patterns,and traffic *** annual average morning concentration of CO_(2),CH_(4)and CO was found(533±105),(7.3±3.1),(10.7±3.0)ppm at Najafgarh and(480±70),(5.2±1.8),(7.8±2.8)ppm at Rajendra Place,respectively.A relationship between concentration of all three gases and meteorological parameters such as temperature,humidity,wind speed and wind direction has also been investigated using Pearson correlation coefficient and pollution rose diagram.A comparable pattern in concentration was observed for all three gases in spatial(location)and temporal(diurnal)*** concentration trend of CO_(2)in different seasons is winter>summer>monsoon,while in the case of CH_(4)winter=summer>monsoon but not any seasonal trend was noted in CO *** is observed that CO_(2)has a good relation with CO(a tracer for vehicular emission)in terms of diurnal variation,whereas,CH_(4)does not represent a relation with CO and CO_(2)diurnally,suggesting that vehicles are the source of CO_(2)but not much contributing to other greenhouse gases like CH_(4).

关键词： Vehicular emission greenhouse gases Harmful pollutants Meteorological parameters

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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

Study of hybrid nanofluid flow in a stationary cone-disk system with temperature-dependent fluid properties

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 677-694页

作者： A.S.JOHN B.MAHANTHESH g.LORENZiNi Center for Mathematical Needs Department of MathematicsCHRIST(Deemed to be University)Karnataka 560029India School of Mathematical and Statistical Sciences The University of Texas Rio Grande ValleyTexas 78539U.S.A. Department of Engineering and Architecture University of ParmaParma 43124Italy

Cone-disk systems find frequent use such as conical diffusers,medi.al devices,various rheometric,and viscosimetry *** this study,we investigate the three-dimensional flow of a water-based Ag-Mg O hybrid nanofluid in a static cone-disk system while considering temperature-dependent fluid *** the variable fluid properties affect the dynamics and heat transfer features is studied by Reynolds's linearized model for variable viscosity and Chiam's model for variable thermal *** single-phase nanofluid model is utilized to describe convective heat transfer in hybrid nanofluids,incorporating the experimental *** model is developed as a coupled system of convective-diffusion equations,encompassing the conservation of momentum and the conservation of thermal energy,in conjunction with an incompressibility condition.A self-similar model is developed by the Lie-group scaling transformations,and the subsequent self-similar equations are then solved *** influence of variable fluid parameters on both swirling and non-swirling flow cases is ***,the Nusselt number for the disk surface is *** is found that an increase in the temperature-dependent viscosity parameter enhances heat transfer characteristics in the static cone-disk system,while the thermal conductivity parameter has the opposite effect.

关键词： hybrid nanofluid cone-disk system laminar flow variable fluid property Nusselt number

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Optimal Control of Service Rates of Discrete-Time(s,Q)Queueing-inventory Systems with Finite Buffer

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Journal of Systems Science and Systems Engineering 2024年第3期33卷 261-280页

作者： L.iniya B.Sivakumar g.Arivarignan School of Mathematics Madurai Kamaraj UniversityMaduraiTamilnaduIndia Department of Statistics Manonmaniam Sundaranar UniversityTirunelveliTamilnaduIndia

This article,we develop an optimal policy to control the service rate of a discrete time queueing-inventory system with finite *** customers arrive according to a Bernoulli process and the service time for the customers are *** the buffer size attains its maximum,any arriving new customers are considered to be *** customers are served one by one according to FCFS rule and each customers request random number of *** inventory is replenished according to a(s,Q)inventory policy with geometric lead *** main objectives of this article are to determine the service rates to be employed at each slot so that the long run expected cost rate is minimized for fixed inventory level and fixed buffer size and to minimize the expected waiting time for a fixed inventory level and fixed buffer *** problems are modelled as Markov decision *** establish the existence of a stationary policy and employ linear programming method to find the optimal service *** provide some numerical examples to illustrate the behaviour of the model.

关键词： Queueing-inventory system discrete time batch demand-Markov decision process

Microbial,immune and antioxidant responses of Nile tilapia with dietary nano-curcumin supplements under chronic low temperatures

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Aquaculture and Fisheries 2024年第1期9卷 57-65页

作者： Mohammed F.El Basuini Mohamed A.A.Zaki Abdelaziz M.El-Hais Mohamed g.Elhanafy Emad H.El-Bilawy Amr i.Zaineldin Mohamed F.A.Abdel-Aziz ibrahim A.Abouelsaad ibrahim TEl-Ratel Kumbukani Mzengereza Ronick S.Shadrack islam i.Teiba Faculty of Agriculture Tanta UniversityTanta31527Egypt King Salman international University South Sinai46618Egypt Faculty of Agriculture Alexandria UniversityAlexandria21526Egypt Animal Health Research institute(AHRi-DOKi) Agriculture Research CenterGiza12619Egypt Fish Rearing Lab. Aquaculture DivisionNational Institute of Oceanography and FisheriesAlexandria21556Egypt Horticulture Department Faculty of AgricultureDamanhour UniversityDamanhur22511Egypt Department of Poultry Production Faculty of AgricultureDamietta UniversityDamietta34517Egypt Laboratory of Aquatic Animal Nutrition Faculty of FisheriesKagoshima UniversityKagoshima890-0065Japan Department of Aquatic and Fisheries Science Mzuzu UniversityMzuzuPrivate Bag 201Malawi Faculty of Aquaculture and Marine Fisheries Arish UniversityArish45516Egypt

A 56-day feeding period was performed to investigate the possible impacts of dietary nano curcumin(0,50,100,150,and 200 ppm)on the growth,nutrient utilization,non-specific immune parameters,antioxidants in Nile tilapia under chronic low temperature(21.02±0.11◦C).Fishes(n=225;initial weight=4.39±0.08 g/fish)were randomly stocked at 15 fish/tank for five experimental groups in *** low-temperature circumstances,dietary curcumin in nano form showed no notable alteration in growth variable,nutrient efficiency,digestive enzymes efficiency,biometric indices,survival rates,and hematological ***,the serum of fishes with nano curcumin diets under low-temperature stress displayed higher total protein as well as lower glucose,cortisol,and total cholesterol compared with the control ***,fish fed nano curcumin diets displayed higher lysozyme and bactericidal activities compared to the control group and the best performance was found at dietary nano curcumin level of≥100 ***,groups fed the basal diet demonstrated the poorest antioxidant capacity,and the best superoxide dismutase(SOD)and glutathione peroxidase(gPx)existed in fish with nano curcumin diets while the best catalase(CAT)efficiency occurred at higher nano curcumin levels≥100 *** addition,higher counts of intestinal microbiota in terms of total bacterial count(TBC),total yeast and molds count(TYMC),and coliform were noticed in fish consumed the basal diet compared to groups fed on nano curcumin *** conclusion,incorporating nano curcumin at a level of≥100 mg/kg diet(particularly at 150 mg/kg)improved a non-specific immune response,antioxidant,and healthier gastrointestinal microbiota in Nile tilapia under chronic low-temperature stress.

关键词： Nano curcumin gastrointestinal microbiota Antioxidants Non-specific immune responses Temperature stress

The great catastrophe: causes of the Permo-Triassic marine mass extinction

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National Science Review 2024年第1期11卷 37-50页

作者： Paul B.Wignall David P.g.Bond School of Earth & Environment University of Leeds School of Environmental Sciences University of Hull

The marine losses during the Permo-Triassic mass extinction were the worst ever experienced. All groups were badly affected, especially amongst the benthos(e.g. brachiopods, corals, bryozoans, foraminifers,ostracods). Planktonic populations underwent a fundamental change with eukaryotic algae being replaced by nitrogen-fixing bacteria, green-sulphur bacteria, sulphate-reducing bacteria and prasinophytes. Detailed studies of boundary sections, especially those in South China, have resolved the crisis to a ～55 kyr interval straddling the Permo-Triassic boundary. Many of the losses occur at the beginning and end of this interval painting a picture of a two-phase extinction. improved knowledge of the extinction has been supported by numerous geochemical studies that allow diverse proposed extinction mechanisms to be studied. A transition from oxygenated to anoxic-euxinic conditions is seen in most sections globally, although the intensity and timing shows regional variability. Decreased ocean ventilation coincides with rapidly rising temperatures and many extinction scenarios attribute the losses to both anoxia and high *** kill mechanisms include ocean acidification for which there is conflicting support from geochemical proxies and, even less likely, siltation(burial under a massive influx of terrigenous sediment) which lacks substantive sedimentological evidence. The ultimate driver of the catastrophic changes at the end of the Permian was likely Siberian Trap eruptions and their associated carbon dioxide emissions with consequences such as warming, ocean stagnation and acidification. Volcanic winter episodes stemming from Siberian volcanism have also been linked to the crisis, but the short-term nature of these episodes(ing evidence for rapid warming during the crisis makes this an unlikely cause. Finally, whilst the extinction is well studied in equatorial latitudes, a different history is found in northern Boreal latitudes

关键词： ocean anoxia ocean acidification siltation productivity collapse volcanic winter

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