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An Experimental Study on Response and Control of a Flapping-Wing Aerial Robot Under Wind Gusts

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Journal of Bionic Engineering 2024年第1期21卷 209-223页

作者： Kazuki Shimura Hikaru Aono Chang-kwon Kang Graduate School of Science and Technology Shinshu University3-15-1 TokidaUedaNagano 3868567Japan Department of Mechanical Engineering and Robotics 3-15-1 TokidaUedaNagano 3868567Japan Department of Mechanical and Aerospace Engineering University of Alabama in HuntsvilleTechnology Hall N266HuntsvilleAL35899USA

Bioinspired flapping-wing micro-air-vehicles(FWMAVs)have the potential to be useful aerial tools for gathering information in various *** recent advancements in manufacturing technologies and better understanding of aerodynamic mechanisms behind of the flapping flight,outdoor flights have become a ***,to fully realize the potential of FWMAVs,further improvements are necessary,particularly in terms of stability and robustness under gusty *** this study,the response and control of a tailless two-winged FWMAV under the wind gusts are *** experiments are conducted with a one-degree-of-freedom gimbal to focus on effects of wind gusts on the rotational motion of the ***-derivative and sliding-mode controls are adopted for the attitude *** present that the body angles changed in time and reached approximately 50°at the maximum due to the wing *** sliding-mode controller can more effectively control the rotational angle in the presence of disturbances and both the wing speed and changes in wind speed have an impact on the effectiveness of attitude *** results contribute to the development of of tailless two-winged,single-motor driven FWMAVs in terms of the design of attitude controller and testing apparatus.

关键词： Flapping-wing micro-air vehicles Sliding-mode control Pitch and roll angle-Wind gus

Aulacaspis yasumatsui infestations accelerate Cycas leaf litter decomposition and nutrient release

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Pedosphere 2024年第3期34卷 681-684页

作者： Thomas E.MARLER Bagong Kaalaman Botanikal Institute 15 Rizal StreetBarangay MalabañasAngeles City 2009(Philippines)

Dear Editor,Numerous aspects of ecosystem ecology are influenced by insects(Prasad,2022).Herbivory of plant organs by insects may influence the biogeochemistry of forests by changing the speed of litter decomposition(Schowalter,2022).Cycas micronesica *** is the only native gymnosperm in the Mariana *** once-abundant tree experienced no known lethal threats prior to the 2003 invasion of Guam by the scale Aulacaspis yasumatsui Takagi(Marler,2012).This insular case study has been the subject of abundant research(Marler et al.,2021).Changes to leaf litter chemistry improved litter quality following *** infestations(Marler and Dongol,2016),but the prediction of increased decomposition speed has not been confirmed with experimental incubations.

关键词： litter fir release

Clinical-based phenotypes in children with pediatric post-COVID-19 condition

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World Journal of Pediatrics 2024年第7期20卷 682-691页

作者： Lieke C.E.Noij Jelle M.Blankestijn Coen R.Lap Marlies A.van Houten Giske Biesbroek Anke-Hilse Maitland-van der Zee Mahmoud I.Abdel-Aziz Johannes B.van Goudoever Mattijs W.Alsem Caroline L.H.Brackel Kim J.Oostrom Simone Hashimoto Suzanne W.J.Terheggen-Lagro Department of Pediatric Pulmonology and Allergy Amsterdam UMCLocation AMCEmma Children’s HospitalAmsterdam University Medical CenterRoom G2-222Meibergdreef 91105AZAmsterdamThe Netherlands Department of Pulmonary Medicine Amsterdam UMCAmsterdamThe Netherlands Department of Pediatrics Spaarne GasthuisHoofddorpThe Netherlands Department of Pediatrics Emma Children’s HospitalAmsterdam University Medical CenterAmsterdamThe Netherlands Department of Rehabilitation Medicine Amsterdam Movement SciencesMeibergdreef 9AmsterdamThe Netherlands Department of Paediatric Pulmonology Department of PaediatricsTergooi MCHilversumThe Netherlands Department of Child and Adolescent Psychiatry and Psychosocial Care Amsterdam UMCAmsterdam Reproduction and DevelopmentAmsterdamThe Netherlands

Background Pediatric post coronavirus disease 2019(COVID-19)condition(PPCC)is a heterogeneous syndrome,which can significantly affect the daily lives of *** study aimed to identify clinically meaningful phenotypes in children with PPCC,to better characterize and treat this *** Participants were children with physician-diagnosed PPCC,referred to the academic hospital Amsterdam UMC in the Netherlands between November 2021 and March *** factors and information on post-COVID symptoms,comorbidities,and impact on daily life were *** clusters were identified using an unsupervised and unbiased approach for mixed data *** Analysis of 111 patients(aged 3–18 years)revealed three distinct clusters within *** 1(n=62,median age=15 years)predominantly consisted of girls(74.2%).These patients suffered relatively more from exercise intolerance,dyspnea,and smell *** 2(n=33,median age=13 years)contained patients with an even gender distribution(51.5%girls).They suffered from relatively more sleep problems,memory loss,gastrointestinal symptoms,and *** 3(n=16,median age=11 years)had a higher proportion of boys(75.0%),suffered relatively more from fever,had significantly fewer symptoms(median of 5 symptoms compared to 8 and 10 for clusters 1 and 2 respectively),and experienced a lower impact on daily *** This study identified three distinct clinical PPCC phenotypes,with variations in sex,age,symptom patterns,and impact on daily *** findings highlight the need for further research to understand the potentially diverse underlying mechanisms contributing to post-COVID symptoms in children.

关键词： Adolescents Clusters Long COVID Pediatric Phenotypes Post-COVID syndrome

Influence of water evaporation on elastohydrodynamic lubrication with water-containing polyalkylene glycols

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Friction 2024年第10期12卷 2370-2388页

作者： Stefan HOFMANN Thomas LOHNER Karsten STAHL Technical University of Munich School of Engineering and DesignDepartment of Mechanical EngineeringGear Research Center(FZG)Boltzmannstraße 1585748 Garching near MunichGermany

The reduction of frictional power losses in power transmitting gears takes a crucial role in the design of energy-and resource-efficient ***-containing lubricants like glycerol and polyalkylene glycols have shown great potential in achieving friction within the superlubricity regime with coefficients of friction lower than 0.01 under elastohydrodynamic ***,a bio-based production of the base stocks can lead to the development of green ***,one challenge associated with the application of water-containing lubricants to gearboxes is the evaporation of water and its impact on the lubricant *** this study,the influence of water evaporation on elastohydrodynamic friction and film thickness was investigated for three water-containing polyalkylene *** nominal water contents of 20 wt%and 40 wt%and two viscosities were *** results show that the friction increases continuously with higher evaporated water content,while the overall friction level remains low in nearly water-free states.A similar trend is observed for film thickness,where the strong increase in viscosity results in a notable increase in film ***,the sensitivity of friction and film thickness to water evaporation is low for small amounts of evaporated *** allows generous thresholds for permissible variations in water content.

关键词： friction superlubricity aqueous lubrication elastohydrodynamic lubrication(EHL) evaporation polyalkylene glycol

Relating estimates of wood properties of birch to stem form, age and species

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Journal of Forestry Research 2024年第3期35卷 1-11页

作者： Grace Jones Maria Ulan Mateusz Liziniewicz Johan Lindeberg Stergios Adamopoulos Teagasc Forestry Development Department Ashtown Research CentreDublin 15 D15DY05Ireland Research Institutes of Sweden(RISE) GoteborgSweden The Forest Research Institute of Sweden(Skogforsk) Ekebo 225026890SvalovSweden Department of Forestry and Wood Technology Linnaeus University35195VaxjoSweden Department of Forest Biomaterials and Technology Swedish University of Agricultural SciencesBox 700875007 UppsalaSweden

Birch has long suffered from a lack of active forest management,leading many researchers to use mate-rial without a detailed management *** collected from three birch(Betula pendula Roth,*** Ehrh.)sites in southern Sweden were analyzed using regression analysis to detect any trends or differences in wood proper-ties that could be explained by stand history,tree age and stem *** sites were genetics trials established in the same *** of acoustic velocity(AV)from non-destructive testing(NDT)and predicted AV had a higher correlation if data was pooled across sites and other stem form factors were considered.A subsample of stems had radial profiles of X-ray wood density and ring width by year created,and wood density was related to ring number from the pith and ring *** seemed likely that wood density was negatively related to ring width for both birch *** models had slight improvements if site and species were included,but only the youngest site with trees at age 15 had both birch *** paper indicated that NDT values need to be considered separately,and any predictive models will likely be improved if they are specific to the site and birch species measured.

关键词： Acoustic velocity Non-destructive testing Predictive models Regression analysis Wood density

Vastly Synergistic Fe_(2)CuNiS_(4)-Nanoarchitectures Anchored 2D-Nano-Sandwich Derived from Flower-Like-CuFeS_(2)/N-Graphene and Cube-Like-NiFeS_(2)/N-CNTs for Water Oxidation and Nitrophenol Reduction

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Energy & Environmental Materials 2024年第6期7卷 274-289页

作者： Gopiraman Mayakrishnan Ramkumar Vanaraj Junpeng Xiong Muhammad Farooq Azeem Ullah Keqin Zhang Seong Cheol Kim Ick Soo Kim Nano Fusion Technology Research Group Division of Molecules and PolymersInstitute for Fiber Engineering(IFES)Interdisciplinary Cluster for Cutting Edge Research(ICCER)Shinshu UniversityTokida 3-15-1UedaNagano 386-8567Japan School of Chemical Engineering Yeungnam UniversityGyeongsan 38541Korea Graduate School of Medicine Scienceand TechnologyShinshu UniversityTokida 3-15-1UedaNagano 386-8567Japan National Engineering Laboratory for Modern Silk College of Textile and Clothing EngineeringSoochow UniversitySuzhou 215123China

Surface area,pore properties,synergistic behavior,homogenous dispersion,and interactions between carbon matrix and metal-nanostructures are the key factors for achieving the better performance of carbon-metal based(electro)***,the traditional hydro-or solvothermal preparation of(electro)catalysts,particularly,bi-or tri-metallic nanostructures anchored graphene(G)or carbon nanotubes(CNTs),often pose to poor metal–support interaction,low synergism,and patchy *** first,bimetallic flower-like-CuFeS_(2)/NG and cube-like-NiFeS_(2)/NCNTs nanocomposites were prepared by solvothermal *** resultant bimetallic nanocomposites were employed to derive the 2D-nano-sandwiched Fe_(2)CuNiS_(4)/NGCNTs-SW(electro)catalyst by a very simple and green urea-mediated“mix-heat”*** desired physicochemical properties of Fe_(2)CuNiS_(4)/NGCNTs-SW such as multiple active sites,strong metal-support interaction,homogenous dispersion and enhanced surface area were confirmed by various microscopic and spectroscopic *** the best of our knowledge,this is the first urea-mediated“mix-heat”method for preparing 2D-nano-sandwiched carbon-metal-based(electro)*** Fe_(2)CuNiS_(4)/NGCNTs-SW was found to be highly effective for alkaline-mediated oxygen evolution reaction at low onset potential of 284.24 mV,and the stable current density of 10 mA cm^(−2) in 1.0 m KOH for 10 ***,the Fe_(2)CuNiS_(4)/NGCNTs-SW demonstrated excellent catalytic activity in the reduction of 4-nitrophenol with good kapp value of 87.71×10^(−2)s^(-1)and excellent reusability over five ***,the developed urea-mediated“mix-heat”method is highly efficient for the preparation of metal-nanoarchitectures anchored 2D-nano-sandwiched(electro)catalysts with high synergism,uniform dispersion and excellent metal-support interaction.

关键词： (electro)catalyst metal-sulfide nanoarchitectures mix-heat N-graphene/NCNTs synergistic effect urea

Design of Biologically Active Macromolecular Ligands and Their Luminescent Complexes with Terbium Ions

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Chinese Journal of Polymer Science 2024年第5期42卷 604-611,I0007页

作者： Tatiana N.Nekrasova Andrei I.Fischer Natalia A.Nesterova Anatoliy V.Dobrodumov Anzhelika V.Garshinina Olga D.Shuvaeva Natalya V.Zakharova Evgenii F.Panarin Institute of Macromolecular Compounds Russian Academy of Sciences31 Bolshoy pr.St Petersburg199004Russia Smorodintsev Research Institute of Influenza Russian Ministry of Health15/17 ul.prof.PopovaSt Petersburg197376Russia

Water-soluble copolymers of p-methacrylamidobenzoic acid(MABA)with neutral comonomers(N-vinylpyrrolidone(VP),N-methyl-N-vinylacetamide(MVAA),N-methacryloyl glucosamine(MAG))and anionic comononer sodium styrene sulfonate(NaSS)were synthesized by radical *** interactions between the prepared copolymers and Tb^(3+)ions in aqueous solutions were studied;the significant influence of chemical structure of a comonomer on luminescence intensity of Tb^(3+)complexes with the copolymers was *** luminescence intensity of Tb^(3+)complexes with the copolymers containing N-vinylamide units(VP,MVAA)is three times more intense than that observed for the complexes between Tb^(3+)and MAG-containing *** the case of NaSS-containing copolymers,the luminescence intensity is controlled by the values of binding constants between Tb^(3+)and MABA and the content of MABA units in a *** studied copolymers and their complexes with Tb^(3+)have low cytotoxicity and a pronounced antiviral activity against human respiratory syncytial virus.

关键词： Luminescence Water-soluble copolymers Lanthanide complexes Antiviral activity Cytotoxicity

Continuous flow pyrolysis of virgin and waste polyolefins:a comparative study,process optimization and product characterization

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Frontiers of Chemical Science and Engineering 2024年第6期18卷 133-149页

作者： Ecrin Ekici Güray Yildiz Magdalena Joka Yildiz Monika Kalinowska ErolŞeker Jiawei Wang Karlsruhe Institute of Technology Institute of Catalysis Research and TechnologyEggenstein-Leopoldshafen 76344Germany Izmir Institute of Technology Faculty of EngineeringDepartment of Energy Systems EngineeringIzmir 35430Türkiye Department of Materials Engineering and Production Faculty of Mechanical EngineeringBialystok University of TechnologyBialystok 15-351Poland Department of Agricultural and Food Engineering and Environmental Development Institute of Civil Engineering and EnergeticsFaculty of Civil Engineering and Environmental SciencesBialystok University of Technology15-351 BialystokPoland Department of Chemistry Biology and BiotechnologyInstitute of Civil Engineering and EnergeticsFaculty of Civil Engineering and Environmental SciencesBialystok University of TechnologyBialystok 15-351Poland Izmir Institute of Technology Faculty of EngineeringDepartment of Chemical EngineeringIzmir 35430Türkiye Energy and Bioproducts Research Institute(EBRI) Aston UniversityBirmingham B47ETUnited Kingdom

Under optimal process conditions,pyrolysis of polyolefins can yield ca.90 wt%of liquid product,i.e.,combination of light oil fraction and heavier *** this work,the experimental findings reported in a selected group of publications concerning the non-catalytic pyrolysis of polyolefins were collected,reviewed,and compared with the ones obtained in a continuously operated bench-scale pyrolysis *** process parameters were used for the pyrolysis of waste and virgin counterparts of high-density polyethylene,low-density polyethylene,polypropylene and a defined mixture of those(i.e.,25:25:50 wt%,respectively).To mitigate temperature drops and enhance heat transfer,an increased feed intake is employed to create a hot melt plastic *** 1.5 g·min^(-1) feed intake,1.1 L·min^(-1) nitrogen flow rate,and a moderate pyrolysis temperature of 450℃,the formation of light hydrocarbons was favored,while wax formation was limited for polypropylene-rich *** of virgin plastics yielded more liquid(maximum 73.3 wt%)than that of waste plastics(maximum 66 wt%).Blending polyethylenes with polypropylene favored the production of liquids and increased the formation of gasoline-range *** products were mainly composed of C3 hydrocarbons,and no hydrogen production was detected due to moderate pyrolysis temperature.

关键词： waste plastics polyolefins chemical recycling pyrolysis alternative fuels waste-to-energy

Oil-in-water nanoemulsions loaded with lycopene extracts encapsulated by spray drying:Formulation,characterization and optimization

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Chinese Journal of Chemical Engineering 2024年第6期70卷 73-81页

作者： Junyang Li Roberta Campardelli Giuseppe Firpo Jingtao Zhang Patrizia Perego Department of Civil Chemical and Environmental Engineering(DICCA)University of GenoaVia Opera Pia 15Genova 16145Italy Department of Physics University of GenoaVia Dodecaneso 32Genova 16146Italy School of Food and Bioengineering Zhengzhou University of Light IndustryZhengzhou 450002China

Lycopene is very susceptible to degradation once released from the protective chromoplast *** this study,oil-in-water(O/W)nanoemulsions coupled with spray drying technology were applied for the encapsulation and stabilization of lycopene extracted from tomato *** extract was obtained by ultrasound-assisted *** were prepared by a high-speed rotor stator using isopropyl myristate as the oil phase and Pluronic F-127 as the emulsifier for the aqueous external *** effect of emulsification process parameters was *** drying of the produced emulsions was attempted to obtain a stabilized dry powder after the addition of a coating *** effect of different coating agents(maltodextrin,inulin,gum arabic,pectin,whey and polyvinylpyrrolidone),drying temperature(120-170℃),and feed flow rate(3-9 ml·min^(-1))on the obtained particles was *** revealed that the emulsion formulation of 20/80(O/W)with 1.5%(mass fraction)of Pluronic F-127 as stabilizer in the aqueous phase resulted in a stable nanoemulsion with droplet sizes in the range of 259-276 nm with a unimodal and sharp size *** extract in the nanoemulsion was well protected at room temperature with a degradation rate of lycopene of about 50%during a month of storage *** most stable emulsions were then processed by spray drying to obtain a dry *** drying was particularly successful when using maltodextrin as a coating agent,obtaining dried spherical particles with mean diameters of(4.87±0.17)μm with a smooth *** possibility of dissolving the spray dried powder in order to *** original emulsion was also successfully verified.

关键词： Emulsions Powders Stability Isopropyl myristate Lycopene Spray-drying