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Controlled flight of a self-powered micro blimp driven by insect-sized flapping-wing thrusters

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Chinese Journal of Aeronautics 2024年第6期37卷 127-136页

作者： Xian YU Zhiwei LIU Jiaming leng Mingjing QI Xiaojun YAN school of Energy and Power Engineering Beihang UniversityBeijing 100191China Collaborative Innovation Center of Advanced Aero-Engine Beijing 100191China National Key Laboratory of science and Technology on Aero-Engine Aero-thermodynamics Beihang UniversityBeijng 100191China Beijing Key Laboratory of Aero-Engine structure and strength Beihang UniversityBeijing 100191China

Micro aerial platforms face significant challenges in achieving long controlled endurance as most of the energy is consumed to overcome the weight of the *** this study,we present a controllable micro blimp that addresses this issue through the use of a helium-filled *** micro blimp has a long axis of 23 cm and is propelled by four insect-sized flapping-wing thrusters,each weighing 80 mg and with a wingspan of 3.5 *** distributed thrusters enable controlled motions and provide the micro blimp with an advantage in flight endurance compared to multirotors or flapping-wing micro aerial vehicles at the same size *** enhance the performance of the controlled flight,we propose a wireless control module that enables manipulation from a distance of up to 100 ***,a smartphone application is developed to send instructions to the circuit board,allowing the blimp to turn left and right,ascend and descend,and achieve a combination of these movements *** findings demonstrate that this micro blimp is one of the smallest controlled self-powered micro blimps to date.

关键词： Microairvehicle Aircraft control self-powered micro blimp Flapping-wing thruster Wireless flight

Combining permissioned blockchain and Bayesian best-worst method for transparent supplier selection in supply chain management

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science China Technological sciences 2024年第8期67卷 2579-2593页

作者： LIU JiaJun ZHANG Jie leng JieWu shanghai Engineering Research Center of Industrial Big Data and Intelligent system Institute of Artificial Intelligence Donghua University state Key Laboratory of Precision Electronic Manufacturing Technology and Equipment Guangdong University of Technology

supplier selection is an important business activity in order to realize the purchasing function in supply chain management. The supplier selection process includes four stages, i.e., bidding inviting, bidding, group decision-making, and results disclosure,involving the participation of manufacturing service demanders(MsDs), manufacturing service suppliers(Msss), and decisionmakers. Nowadays, all the participants have raised concerns about the increased transparency in supplier selection. Therefore,this study proposes a transparent supplier selection method by considering the engagement of suppliers. In this method, the Bayesian best-worst method(Bayesian BWM) is used to aggregate decision-makers' preferences into the overall optimal weights of the alternative Msss, and the Mss with the largest weight is considered the suitable Mss for MsDs. Furthermore,blockchain is introduced to record the decision-making process information about supplier selection through a customized smart contract, where Msss act as supervisors to supervise the decision-making process through the distributed consensus mechanism rather than directly participate in the decision-making process. Finally, a case study of supplier selection in purchasing vibration acceleration sensors is presented. The result shows that the proposed method can support MsDs in selecting suitable Mss from alternative Msss by aggregating decision-makers' preferences, and blockchain can provide credible information about the supplier selection process for Msss, MsDs, and decision-makers. In this way, the transparency of supplier selection is enhanced.

关键词： blockchain supplier selection supply chain transparency Bayesian BWM group decision-making

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Utilization of Basalt saw Mud as a spherical Porous Functional Aggregate for the Preparation of Ordinary structure Concrete

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Journal of Wuhan University of Technology(Materials science) 2024年第2期39卷 364-375页

作者：周永祥关青锋 leng Faguang WANG Jing LI Tianjun Faculty of Architecture Civil and Transportation EngineeringBeijing University of TechnologyBeijing 100124China Key Laboratory of Urban security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing 100012China school of Materials science and Engineering Southeast UniversityNanjing 211189China Institute of Building Materials China Academy of Building ResearchBeijing 100013China state Key Laboratory of Building safety and Built Environment Beijing 100013China Zhejiang Chinavigor E.P.Technology Co. Ltd.Zhejiang 315043China

To promote the production and application of artificial aggregates,save natural sand resources and protect the ecological environment,we evaluated the feasibility of using spherical porous functional aggregates(sPFAs) formed by basalt saw mud under autoclave curing in ordinary structural *** our work,two types of prewetted functional aggregates were taken as replacements for natural aggregates with different volume substitution rates(0%,5%,10%,15%,20%,25%,and 30%) in the preparation of ordinary structural concrete with water-to-binder ratios(W/B) of 0.48 and *** effects of the functional aggregate properties and content,W/B,and curing age on the fluidity,density,mechanical properties and autogenous shrinkage of ordinary concrete were *** experimental results showed that the density of concrete declined at a rate of not more than 5%,and the 28 d compressive strength could reach 31.0-68.2 *** W/B,long curing age and high-quality functional aggregates were conducive to enhancing the mechanical properties of sPFAs *** the rolling effects,sPFAs can optimize the particle gradation of aggregate systems and improve the fluidity of concrete,and the water stored inside sPFAs provides an internal curing effect,which prolongs the cement hydration process and considerably reduces the autogenous shrinkage of *** exhibits high strength and high density,as well as being more cost-effective and ecological,and is expected to be widely employed in ordinary structural concrete.

关键词： lightweight concrete civil concrete building basalt saw mud fly ash internal curing environmentally friendly

Characterization of blueberry exosome-like nanoparticles and miRNAs with potential cross-kingdom human gene targets

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Food science and Human Wellness 2024年第2期13卷 869-878页

作者： Yangfan leng Liubin Yang siyi Pan Leilei Zhan Fang Yuan College of Food science and Technology Huazhong Agricultural UniversityWuhan 430070China Hubei Key Laboratory of Fruit&Vegetable Processing&Quality Control Huazhong Agricultural UniversityWuhan 430070China Wuhan GeneCreate Biological Engineering Co. Ltd.Wuhan 430070China

Edible plant derived exosome-like nanoparticles(ELNs)have been shown to have multiple nutraceutical ***,the diversity of plant materials makes the plant derived ELN study *** efforts are still needed to explore the feasible isolation methods of edible plant derived ELNs and the possible roles of food-derived ELNs in improving human *** this study,a size exclusion chromatography based method was compared with the traditional ultracentrifugation method to isolate blueberry derived ELNs(B-ELNs),and the miRNA profile of B-ELNs was analyzed by high-throughput sequencing.A total of 36 miRNAs were found to be enriched in B-ELNs compared with berry tissue,and their potential cross-kingdom human gene targets were further *** showed that size exclusion chromatography was effective for B-ELN *** most abundant miRNAs in B-ELNs mainly belonged to the miR166 family and miR396 *** gene prediction indicated that B-ELNs could potentially regulate pathways related to the human digestive system,immune system and infectious diseases.

关键词： Edible plant derived exosomes-like nanoparticles size exclusion chromatography miRNA Target gene prediction Blueberry

A state-of-the-art review of the development of self-healing concrete for resilient infrastructure

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Frontiers of structural and Civil Engineering 2024年第2期18卷 151-169页

作者： Dong LU Xi JIANG Yao ZHANG shaowei ZHANG Guoyang LU Zhen leng Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong Kong 999077China Laboratory of Fire safety School of Safety Engineering and Emergency ManagementShijiazhuang Tiedao UniversityShijiazhuang 050043China Department of Architecture and Civil Engineering City University of Hong KongHong Kong 999077China

The brittleness of cement composites makes cracks almost inevitable,producing a serious limitation on the lifespan,resilience,and safety of concrete *** address this brittleness,self-healing concrete has been developed for regaining its mechanical and durability properties after becoming cracked,thereby promising sustainable development of concrete *** paper provides a comprehensive review of the latest developments in self-healing *** begins by summarizing the methods used to evaluate the self-healing efficiency of ***,it compares strategies for achieving healing *** then discusses the typical approaches for developing self-healing ***,critical insights are proposed to guide future studies on the development of novel self-healing *** review will be useful for researchers and practitioners interested in the field of self-healing concrete and its potential to improve the durability,resilience,and safety of concrete infrastructure.

关键词： resilient infrastructure sustainable concrete self-healing cracks

Generation,bonding and reactivity of transient zinc-substituted silylenes

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science China Chemistry 2024年第4期67卷 1256-1262页

作者： Cheng Xu Thayalan Rajeshkumar Laurent Maron Xuebing leng Yaofeng Chen state Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032China spin-X Institute School of Chemistry and Chemical EngineeringState Key Laboratory of Luminescent Materials and DevicesGuangdong-Hong Kong-Macao Joint Laboratory of Optoelectronic and Magnetic Functional MaterialsSouth China University of TechnologyGuangzhou 510641China LPCNO CNRS&INSAUniversitéPaul SabatierToulous 31077France

The metal-substituted silylenes are of high interest,as the theoretical studies indicated that the silylenes with electropositive substituents have a small ΔE_(s-T)(singlet-triplet energy gap)or even the ground-state ***,such compounds are highly unstable,and only two transient alkali metal-substituted silylenes M(^(t)Bu_(3)si)si:(M=Li,K)were generated by photoextrusion of the alkali metal-substituted silacyclopropenes and merely studied by spectroscopic method(EPR)at low temperature(14 to 50 K).Herein,we report the generation of transient zinc-substituted silylenes from zinc silacyclopropanyl complexes under very mild and convenient *** generated transient zinc-substituted silylenes are highly reactive and undergo intermolecular cycloaddition with alkenes for the synthesis of zinc-substituted si-heterocyclic *** there is no substrate,the zinc-substituted silylenes attack the C-C bonds of the β-diketiminato ligands and break the C-C *** studies further highlight the silylene nature of the zinc-substituted silylene and a very small ΔE_(s-T)(4.4 kcal/mol).

关键词： zinc complex silylene C-C bond cleavage cycloaddition DFT calculations

Access to Versatile Functionalized Cu(Ⅲ) Complexes Enabled by Direct Transmetalation to Well-Defined Copper(Ⅲ) Fluoride Complex Me_(4)N^(+)[Cu(CF_(3))_(3)F]^(-)

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Chinese Journal of Chemistry 2024年第10期42卷 1107-1113页

作者： Guangyu Wang Huaiyuan Li Xuebing leng Long Lu Qilong shen Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling LuShanghai 200032China

The invention of a well-defined Cu(Ⅲ)fluoride complex Me_(4)N^(+)[Cu(CF_(3))_(3)(F)]^(-)1 enabled to access a versatile of functionalized Cu(Ⅲ)complexes[Me_(4)N]^(+)[Cu(X)(CF_(3))_(3)]^(-)(X=C_(6)F_(5),C_(6)F_(5)C≡C,CN,Cl,N_(3),^(t)BuOO,sCN,OAc,sAr),many of them for the first *** availability of these complexes allowed us to evaluate the trans-influence order of ligand in Cu(Ⅲ)complexes:Bn>CF_(3)^(-)>C_(6)F_(5)^(-)>N_(3)^(-)>py~CH_(3)^(-)~C_(6)F_(5)C≡C>NO_(2)PhO^(-)~^(t)BuOO^(-)~CH_(3)COO^(-)>F^(-).

关键词： Fluorine Copper Cu(Ⅲ) Cu(Ⅲ)fluoride Trifluoromethyl

Bunch-length measurement at a bunch-by-bunch rate based on time–frequency-domain joint analysis techniques and its application

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Nuclear science and Techniques 2024年第4期35卷 165-175页

作者： Hong-shuang Wang Xing Yang Yong-Bin leng Yi-Mei Zhou Ji-Gang Wang shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of sciences Beijing 100049China National synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230026China shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China

This paper presents a new technique for measuring the bunch length of a high-energy electron beam at a bunch-by-bunch rate in storage *** technique uses the time–frequency-domain joint analysis of the bunch signal to obtain bunch-by-bunch and turn-by-turn longitudinal parameters,such as bunch length and synchronous *** bunch signal is obtained using a button electrode with a bandwidth of several *** data acquisition device was a high-speed digital oscilloscope with a sampling rate of more than 10 Gs/s,and the single-shot sampling data buffer covered thousands of *** bunch-length and synchronous phase information were extracted via offline calculations using Python *** calibration coefficient of the system was determined using a commercial streak ***,this technique was tested on two different storage rings and successfully captured various longitudinal transient processes during the harmonic cavity debugging process at the shanghai synchrotron Radiation Facility(ssRF),and longitudinal instabilities were observed during the single-bunch accumulation process at Hefei Light source(HLs).For Gaussian-distribution bunches,the uncertainty of the bunch phase obtained using this technique was better than 0.2 ps,and the bunch-length uncertainty was better than 1 *** dynamic range exceeded 10 *** technology is a powerful and versatile beam diagnostic tool that can be conveniently deployed in high-energy electron storage rings.

关键词： Bunch-by-bunch diagnostic Bunch-length measurement synchronous phase measurement Joint time–frequency-domain analysis Longitudinal instability

Mechanical Properties and Electronic structures of M(M=Ti,V,Cr,Mn and Fe)Dopedβ-si_(3)N_(4) from First-Principle

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Journal of Wuhan University of Technology(Materials science) 2024年第3期39卷 639-644页

作者：龙敏黄福祥 XU Liangyu LI Xuemei YANG Zhou leng Yue MEI shini school of Materials science and Engineering Chongqing University of TechnologyChongqing 400054China

The structures,mechanical properties and electronic structures of M metals(M=Ti,V,Cr,Mn and Fe)dopedβ-si_(3)N_(4) were investigated by First-principles calculations within *** calculated lattice parameters ofβ-si_(3)N_(4) were consistent with previous *** cohesive energy and formation enthalpy show that initialβ-si_(3)N_(4) has the highest structural *** calculated elastic constant and the Voigt-Reuss-Hill approximation indicate that elastic moduli ofβ-si_(3)N_(4) are slightly reduced by M *** on Poisson’s and Pugh’s ratio,β-si_(3)N_(4) is a ductile material and the toughness ofβ-si_(3)N_(4) increases with M doping,and Fe doping exhibited the best *** results of density of states,charge distributions and overlapping populations indicate thatβ-si_(3)N_(4) has the strong covalent and ionic bond strength between N and si.

关键词： first-principles β-si_(3)N_(4) mechanical properties electronic structure