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Evaluating Methods of Visual Assistance for Workers to Improve Quality and Usability in Individualized Kitchen Cabinet Assembly
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作者 Albert Eff Michael S. J. Walter 《Journal of Computer and Communications》 2024年第2期156-172,共17页
In times of digitalisation, visual assistance systems in assembly are increasingly important. The design of these assembly systems needs to be highly complex to meet the requirements. Due to the increasing number of v... In times of digitalisation, visual assistance systems in assembly are increasingly important. The design of these assembly systems needs to be highly complex to meet the requirements. Due to the increasing number of variants in production processes, as well as shorter innovation and product life cycles, assistance systems should improve quality and reduce complexity of assembly processes. However, many large kitchen manufacturers still assemble kitchen cabinets manually, due to the high variety of components, such as rails and fittings. This paper focuses on the analysis and evaluation of virtual assistance systems to improve quality and usability in individualised kitchen cabinet assembly processes at a large German manufacturer. A solution is identified and detailed. 展开更多
关键词 Digitalisation assembly Process Visual Assistance USABILITY Human-Centred assembly Design
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Gapless Genome Assembly of ZH8015 and Preliminary Multi-Omics Analysis to Investigate ZH8015's Responses Against Brown Planthopper Infestation
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作者 LI Dian DUAN Wenjing +5 位作者 LIU Qun’en WU Weixun ZHAN Xiaodeng SUN Lianping ZHANG Yingxin CHENG Shihua 《Rice science》 SCIE CSCD 2024年第3期317-327,I0042-I0045,共15页
Accurate genomic information is essential for advancing genetic breeding research in specific rice varieties.This study presented a gapless genome assembly of the indica rice cultivar Zhonghui 8015(ZH8015)using Pac Bi... Accurate genomic information is essential for advancing genetic breeding research in specific rice varieties.This study presented a gapless genome assembly of the indica rice cultivar Zhonghui 8015(ZH8015)using Pac Bio HiFi,Hi-C,and ONT(Oxford Nanopore Technologies)ultra-long sequencing technologies,annotating 43037 gene structures.Subsequently,utilizing this genome along with transcriptomic and metabolomic techniques,we explored ZH8015's response to brown planthopper(BPH)infestation.Continuous transcriptomic sampling indicated significant changes in gene expression levels around 48 h after BPH feeding.Enrichment analysis revealed particularly significant alterations in genes related to reactive oxygen species scavenging and cell wall formation.Metabolomic results demonstrated marked increases in levels of several monosaccharides,which are components of the cell wall and dramatic changes in flavonoid contents.Omics association analysis identified differentially expressed genes associated with key metabolites,shedding light on ZH8015's response to BPH infestation.In summary,this study constructed a reliable genome sequence resource for ZH8015,and the preliminary multi-omics results will guide future insect-resistant breeding research. 展开更多
关键词 brown planthopper gapless genome genome assembly multi-omics Nilaparvata lugens rice
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Ionic Liquid-Enhanced Assembly of Nanomaterials for Highly Stable Flexible Transparent Electrodes
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作者 Jianmin Yang Li Chang +2 位作者 Xiqi Zhang Ziquan Cao Lei Jiang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第7期441-455,共15页
The controlled assembly of nanomaterials has demon-strated significant potential in advancing technological devices.However,achieving highly efficient and low-loss assembly technique for nanomate-rials,enabling the cr... The controlled assembly of nanomaterials has demon-strated significant potential in advancing technological devices.However,achieving highly efficient and low-loss assembly technique for nanomate-rials,enabling the creation of hierarchical structures with distinctive func-tionalities,remains a formidable challenge.Here,we present a method for nanomaterial assembly enhanced by ionic liquids,which enables the fabrication of highly stable,flexible,and transparent electrodes featuring an organized layered structure.The utilization of hydrophobic and non-volatile ionic liquids facilitates the production of stable interfaces with water,effectively preventing the sedimentation of 1D/2D nanomaterials assembled at the interface.Furthermore,the interfacially assembled nanomaterial monolayer exhibits an alternate self-climbing behavior,enabling layer-by-layer transfer and the formation of a well-ordered MXene-wrapped silver nanowire network film.The resulting composite film not only demonstrates exceptional photoelectric performance with a sheet resistance of 9.4Ωsq^(-1) and 93%transmittance,but also showcases remarkable environmental stability and mechanical flexibility.Particularly noteworthy is its application in transparent electromagnetic interference shielding materials and triboelectric nanogenerator devices.This research introduces an innovative approach to manufacture and tailor functional devices based on ordered nanomaterials. 展开更多
关键词 Ionic liquids assembly Silver nanowires MXene nanosheets Flexible transparent electrodes
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A telomere-to-telomere genome assembly of Zhonghuang 13,a widely-grown soybean variety from the original center of Glycine max
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作者 Anqi Zhang Tangchao Kong +21 位作者 Baiquan Sun Shizheng Qiu Jiahe Guo Shuyong Ruan Yu Guo Jirui Guo Zhishuai Zhang Yue Liu Zheng Hu Tao Jiang Yadong Liu Shuqi Cao Shi Sun Tingting Wu Huilong Hong Bingjun Jiang Maoxiang Yang Xiangyu Yao Yang Hu Bo Liu Tianfu Han Yadong Wang 《The Crop Journal》 SCIE CSCD 2024年第1期142-153,共12页
Soybean(Glycine max)stands as a globally significant agricultural crop,and the comprehensive assembly of its genome is of paramount importance for unraveling its biological characteristics and evolutionary history.Nev... Soybean(Glycine max)stands as a globally significant agricultural crop,and the comprehensive assembly of its genome is of paramount importance for unraveling its biological characteristics and evolutionary history.Nevertheless,previous soybean genome assemblies have harbored gaps and incompleteness,which have constrained in-depth investigations into soybean.Here,we present Telomere-to-Telomere(T2T)assembly of the Chinese soybean cultivar Zhonghuang 13(ZH13)genome,termed ZH13-T2T,utilizing PacBio Hifi and ONT ultralong reads.We employed a multi-assembler approach,integrating Hifiasm,NextDenovo,and Canu,to minimize biases and enhance assembly accuracy.The assembly spans 1,015,024,879 bp,effectively resolving all 393 gaps that previously plagued the reference genome.Our annotation efforts identified 50,564 high-confidence protein-coding genes,707 of which are novel.ZH13-T2T revealed longer chromosomes,421 not-aligned regions(NARs),112 structure variations(SVs),and a substantial expansion of repetitive element compared to earlier assemblies.Specifically,we identified 25.67 Mb of tandem repeats,an enrichment of 5S and 48S rDNAs,and characterized their genotypic diversity.In summary,we deliver the first complete Chinese soybean cultivar T2T genome.The comprehensive annotation,along with precise centromere and telomere characterization,as well as insights into structural variations,further enhance our understanding of soybean genetics and evolution. 展开更多
关键词 SOYBEAN Telomere-to-Telomere assembly Zhonghuang 13 Structure variations
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Self-assembly of tau fragments as a key pathologic event in tauopathies
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作者 Ly Thi Huong Luu Le Jung Hoon Lee Min Jae Lee 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第12期2565-2566,共2页
Tau protein is encoded by the microtubuleassociated protein tau(MAPT)gene and stabilizes microtubules in the neurons.Tau has unique biophysical properties that make it both highly water-soluble and positively charged.... Tau protein is encoded by the microtubuleassociated protein tau(MAPT)gene and stabilizes microtubules in the neurons.Tau has unique biophysical properties that make it both highly water-soluble and positively charged.Although tau is an intrinsically disordered protein lacking defined secondary structures,it can acquire highly organized-sheet structures and stack into a filamentous inclusion such as a paired helical filament(PHF). 展开更多
关键词 TAU PATHOLOGIC assembly
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A telomere-to-telomere genome assembly of Hongyingzi,a sorghum cultivar used for Chinese Baijiu production
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作者 Yanqing Ding Yilin Wang +12 位作者 Jianxia Xu Feng Jiang Wenzhen Li Qiaoling Zhang Longping Yang Zhenyu Zhao Bin Cheng Ning Cao Xu Gao Xin Zhang Guihua Zou Fan Yang Liyi Zhang 《The Crop Journal》 SCIE CSCD 2024年第2期635-640,共6页
Sorghum(Sorghum bicolor(L.)Moench)is a world cereal crop used in China for producing Baijiu,a distilled spirit.We report a telomere-to-telomere genome assembly of the Baijiu cultivar Hongyingzi,HYZ-T2T,using ultralong... Sorghum(Sorghum bicolor(L.)Moench)is a world cereal crop used in China for producing Baijiu,a distilled spirit.We report a telomere-to-telomere genome assembly of the Baijiu cultivar Hongyingzi,HYZ-T2T,using ultralong reads.The 10 chromosome pairs contained 33,462 genes,of which 93%were functionally annotated.The 20 telomeres and 10 centromeric regions on the HYZ-T2T chromosomes were predicted and two consecutive large inversions on chromosome 2 were characterized.A 65-gene reconstruction of the metabolic pathway of tannins,the flavor substances in Baijiu,was performed and may advance the breeding of sorghum cultivars for Baijiu production. 展开更多
关键词 SORGHUM Telomere-to-telomere assembly Hongyingzi(HYZ) Chinese Baijiu-making cultivar
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Digital Twin Modeling and Simulation Optimization of Transmission Front and Middle Case Assembly Line
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作者 Xianfeng Cao Meihua Yao +2 位作者 Yahui Zhang Xiaofeng Hu Chuanxun Wu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期3233-3253,共21页
As the take-off of China’s macro economy,as well as the rapid development of infrastructure construction,real estate industry,and highway logistics transportation industry,the demand for heavy vehicles is increasing ... As the take-off of China’s macro economy,as well as the rapid development of infrastructure construction,real estate industry,and highway logistics transportation industry,the demand for heavy vehicles is increasing rapidly,the competition is becoming increasingly fierce,and the digital transformation of the production line is imminent.As one of themost important components of heavy vehicles,the transmission front andmiddle case assembly lines have a high degree of automation,which can be used as a pilot for the digital transformation of production.To ensure the visualization of digital twins(DT),consistent control logic,and real-time data interaction,this paper proposes an experimental digital twin modeling method for the transmission front and middle case assembly line.Firstly,theDT-based systemarchitecture is designed,and theDT model is created by constructing the visualization model,logic model,and data model of the assembly line.Then,a simulation experiment is carried out in a virtual space to analyze the existing problems in the current assembly line.Eventually,some improvement strategies are proposed and the effectiveness is verified by a new simulation experiment. 展开更多
关键词 Transmission front and middle case assembly line digital twin(DT) simulating optimization intelligent manufacturing
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Response and assembly of abundant and rare taxa in Zaopei under different combination patterns of Daqu and pit mud:from microbial ecology to Baijiu brewing microecosystem
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作者 Yu Mu Jun Huang +5 位作者 Rongqing Zhou Suyi Zhang Hui Qin Hanlan Tang Qianglin Pan Huifang Tang 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1439-1452,共14页
The quality and aroma of strong-flavor Baijiu are mainly dependent on Daqu,pit mud(PM),and the interaction of both.However,little is known about how their combination patterns affect the microbiome and metabolome of Z... The quality and aroma of strong-flavor Baijiu are mainly dependent on Daqu,pit mud(PM),and the interaction of both.However,little is known about how their combination patterns affect the microbiome and metabolome of Zaopei,especially the metabolic function of rare taxa.Here,an experiment on industrial size was designed to assess the effects of 6 combinations(3 kinds of Daqu×2 kinds of PM)on the composition and assembly of different taxa,as well as the flavor profile.The results showed that Zaopei's microbiota was composed of a few abundant taxa and enormous rare taxa,and rare bacterial and abundant fungal subcommunities were significantly affected by combination patterns.The assembly processes of abundant/rare taxa and bacterial/fungal communities were distinct,and environmental changes mediated the balance between stochastic and deterministic processes in rare bacteria assembly.Furthermore,specific combination patterns improved the flavor quality of Zaopei by enhancing the interspecies interaction,which was closely related to rare taxa,especially rare bacteria.These findings highlighted that rare bacteria might be the keystone in involving community interaction and maintaining metabolic function,which provided a scientific foundation for better understanding and regulating the brewing microbiota from the viewpoint of microbial ecology. 展开更多
关键词 Bioaugmented Daqu Artificial pit mud Abundant and rare taxa Community assembly Metabolic function
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Designing Membrane Electrode Assembly for Electrochemical CO_(2)Reduction:a Review
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作者 Xuerong Wang Shulin Zhao +4 位作者 Tao Guo Luyao Yang Qianqian Zhao Yuping Wu Yuhui Chen 《Transactions of Tianjin University》 EI CAS 2024年第2期117-129,共13页
Currently, the electrochemical CO_(2) reduction reaction (CO_(2) RR) can realize the resource conversion of CO_(2) , which is a promising approach to carbon resource use. Important advancements have been made in explo... Currently, the electrochemical CO_(2) reduction reaction (CO_(2) RR) can realize the resource conversion of CO_(2) , which is a promising approach to carbon resource use. Important advancements have been made in exploring the CO_(2) RR performance and mechanism because of the rational design of electrolyzer systems, such as H-cells, flow cells, and catalysts. Considering the future development direction of this technology and large-scale application needs, membrane electrode assembly (MEA) systems can improve energy use efficiency and achieve large-scale CO_(2) conversion, which is considered the most promising technology for industrial applications. This review will concentrate on the research progress and present situation of the MEA component structure. This paper begins with the composition and construction of a gas diff usion electrode. Then, the application of ion-exchange membranes in MEA is introduced. Furthermore, the eff ects of pH and the anion and cation of the anolyte on MEA performance are explored. Additionally, we present the anode reaction type in MEA. Finally, the challenges in this field are summarized, and upcoming trends are projected. This review should offer researchers a clearer picture of MEA systems and provide important, timely, and valuable insights into rational electrolyzer design to facilitate further development of CO_(2) electrochemical reduction. 展开更多
关键词 CO_(2)reduction ELECTROCATALYSIS Membrane electrode assembly
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Target-induced Trivalent G-quadruplex/hemin DNAzyme for Colorimetric Detection of Hg^(2+) Based on an Exonuclease III Assisted Catalytic Hairpin Assembly
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作者 Zhenghua LIU Zhonghai LI 《Agricultural Biotechnology》 2024年第1期51-57,共7页
Mercury ion(Hg^(2+)),a highly noxious of heavy metalion,has detrimental effects on the ecological environment and human health.Herein,we have developed an exonuclease III(Exo III)assisted catalytic hairpin assembly fo... Mercury ion(Hg^(2+)),a highly noxious of heavy metalion,has detrimental effects on the ecological environment and human health.Herein,we have developed an exonuclease III(Exo III)assisted catalytic hairpin assembly formation of a trivalent G-quadruplex/hemin DNAzyme for colorimetric detection of Hg^(2+).A hairpin DNA(Hr)was designed with thymine-Hg^(2+)-thymine pairs that catalyzed by Exo III is prompted to happen upon binding Hg^(2+).A released DNA fragment triggers the catalytic assembly of other three hairpins(H1,H2,and H3)to form many trivalent G-quadruplex/hemin DNA enzymes for signal output.The developed sensor shows a dynamic range from 2 pM to 2μM,with an impressively low detection limit of 0.32 pM for Hg^(2+)detection.Such a sensor also has good selectivity toward Hg^(2+)detection in the presence of other common metal ions.This strategy shows the great potential for visual detection with portable type. 展开更多
关键词 G-quadruplex/hemin DNAzyme Multivalence Catalytic hairpin assembly Exonuclease III Signal amplification Colorimetric detection
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Telomere-to-telomere and gap-free reference genome assembly of the kiwifruit Actinidia chinensis 被引量:8
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作者 Junyang Yue Qinyao Chen +14 位作者 Yingzhen Wang Lei Zhang Chen Ye Xu Wang Shuo Cao Yunzhi Lin Wei Huang He Xian Hongyan Qin Yanli Wang Sijia Zhang Ying Wu Songhu Wang Yi Yue Yongsheng Liu 《Horticulture Research》 SCIE CSCD 2023年第2期134-146,共13页
Kiwifruit is an economically and nutritionally important fruit crop with extremely high contents of vitamin C.However,the previously released versions of kiwifruit genomes all have a mass of unanchored or missing regi... Kiwifruit is an economically and nutritionally important fruit crop with extremely high contents of vitamin C.However,the previously released versions of kiwifruit genomes all have a mass of unanchored or missing regions.Here,we report a highly continuous and completely gap-free reference genome of Actinidia chinensis cv.‘Hongyang’,named Hongyang v4.0,which is the first to achieve two de novo haploid-resolved haplotypes,HY4P and HY4A.HY4P and HY4A have a total length of 606.1 and 599.6 Mb,respectively,with almost the entire telomeres and centromeres assembled in each haplotype.In comparison with Hongyang v3.0,the integrity and contiguity of Hongyang v4.0 is markedly improved by filling all unclosed gaps and correcting some misoriented regions,resulting in∼38.6–39.5 Mb extra sequences,which might affect 4263 and 4244 protein-coding genes in HY4P and HY4A,respectively.Furthermore,our gap-free genome assembly provides the first clue for inspecting the structure and function of centromeres.Globally,centromeric regions are characterized by higher-order repeats that mainly consist of a 153-bp conserved centromere-specific monomer(Ach-CEN153)with different copy numbers among chromosomes.Functional enrichment analysis of the genes located within centromeric regions demonstrates that chromosome centromeres may not only play physical roles for linking a pair of sister chromatids,but also have genetic features for participation in the regulation of cell division.The availability of the telomere-to-telomere and gap-free Hongyang v4.0 reference genome lays a solid foundation not only for illustrating genome structure and functional genomics studies but also for facilitating kiwifruit breeding and improvement. 展开更多
关键词 BREEDING LINKING assembly
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quarTeT: a telomere-to-telomere toolkit for gap-free genome assembly and centromeric repeat identification 被引量:2
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作者 Yunzhi Lin Chen Ye +12 位作者 Xingzhu Li Qinyao Chen Ying Wu Feng Zhang Rui Pan Sijia Zhang Shuxia Chen Xu Wang Shuo Cao Yingzhen Wang Yi Yue Yongsheng Liu Junyang Yue 《Horticulture Research》 SCIE CSCD 2023年第8期122-128,共7页
A high-quality genome is the basis for studies on functional,evolutionary,and comparative genomics.The majority of attention has been paid to the solution of complex chromosome structures and highly repetitive sequenc... A high-quality genome is the basis for studies on functional,evolutionary,and comparative genomics.The majority of attention has been paid to the solution of complex chromosome structures and highly repetitive sequences,along with the emergence of a new‘telomere-to-telomere(T2T)assembly’era.However,the bioinformatic tools for the automatic construction and/or characterization of T2T genome are limited.Here,we developed a user-friendly web toolkit,quarTeT,which currently includes four modules:AssemblyMapper,GapFiller,TeloExplorer,and CentroMiner.First,AssemblyMapper is designed to assemble phased contigs into the chromosome-level genome by referring to a closely related genome.Then,GapFiller would endeavor to fill all unclosed gaps in a given genome with the aid of additional ultra-long sequences.Finally,TeloExplorer and CentroMiner are applied to identify candidate telomere and centromere as well as their localizations on each chromosome.These four modules can be used alone or in combination with each other for T2T genome assembly and characterization.As a case study,by adopting the entire modular functions of quarTeT,we have achieved the Actinidia chinensis genome assembly that is of a quality comparable to the reported genome Hongyang v4.0,which was assembled with the addition of manual handling.Further evaluation of CentroMiner by searching centromeres in Arabidopsis thaliana and Oryza sativa genomes showed that quarTeT is capable of identifying all the centromeric regions that have been previously detected by experimental methods.Collectively,quarTeT is an efficient toolkit for studies of large-scale T2T genomes and can be accessed at http://www.atcgn.com:8080/quarTeT/home.html without registration. 展开更多
关键词 SEARCHING assembly ALONE
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Modular flexible“Tetris”microsatellite platform based on sandwich assembly mode 被引量:1
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作者 ZHOU Jun ZHANG Hao +2 位作者 LIU Guanghui CHENG Cheng ZHANG Jiaolong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第4期924-938,共15页
In this paper,a flexible modular“Tetris”microsatellite platform is studied to implement the rapid integration and assembly of microsatellites.The proposed microsatellite platform is fulfilled based on a sandwich ass... In this paper,a flexible modular“Tetris”microsatellite platform is studied to implement the rapid integration and assembly of microsatellites.The proposed microsatellite platform is fulfilled based on a sandwich assembly mode which consists of the isomorphic module structure and the standard mechanical-electric-data-thermal interfaces.The advantages of the sandwich assembly mode include flexible reconfiguration and efficient assembly.The prototype of the sandwich assembly mode is built for verifying the performance and the feasibility of the proposed mechanical-electric-data-thermal interfaces.Finally,an assembly case is accomplished to demonstrate the validity and advantages of the proposed“Tetris”microsatellite platform. 展开更多
关键词 modular microsatellite design flexible platform sandwich assembly mode isomorphic module structure standard mechanical-electric-data-thermal interface
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Progress and perspective of single-atom catalysts for membrane electrode assembly of fuel cells 被引量:1
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作者 Zhongxin Song Junjie Li +4 位作者 Qianling Zhang Yongliang Li Xiangzhong Ren Lei Zhang Xueliang Sun 《Carbon Energy》 SCIE CSCD 2023年第7期38-56,共19页
A fuel cell is an energy conversion device that can continuously input fuel and oxidant into the device through an electrochemical reaction to release electrical energy.Although noble metals show good activity in fuel... A fuel cell is an energy conversion device that can continuously input fuel and oxidant into the device through an electrochemical reaction to release electrical energy.Although noble metals show good activity in fuel cell-related electrochemical reactions,their ever-increasing price considerably hinders their industrial application.Improvement of atom utilization efficiency is considered one of the most effective strategies to improve the mass activity of catalysts,and this allows for the use of fewer catalysts,saving greatly on the cost.Thus,single-atom catalysts(SACs)with an atom utilization efficiency of 100%have been widely developed,which show remarkable performance in fuel cells.In this review,we will describe recent progress on the development of SACs for membrane electrode assembly of fuel cell applications.First,we will introduce several effective routes for the synthesis of SACs.The reaction mechanism of the involved reactions will also be introduced as it is highly determinant of the final activity.Then,we will systematically summarize the application of Pt group metal(PGM)and nonprecious group metal(non-PGM)catalysts in membrane electrode assembly of fuel cells.This review will offer numerous experiences for developing potential industrialized fuel cell catalysts in the future. 展开更多
关键词 fuel cells membrane electrode assembly oxygen reduction reaction reaction mechanism single-atom catalysts
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Coin-structured tunable beam shaping assembly design for accelerator-based boron neutron capture therapy for tumors at different depths and sizes 被引量:1
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作者 Zhao‑Peng Qiao Yao‑Cheng Hu +5 位作者 Quan‑Xu Jiang Jing‑Jing Fan Isao Murata Rui‑Rui Liu Bo Wang Sheng Wang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第12期66-76,共11页
In the past decade,boron neutron capture therapy utilizing an accelerator-based neutron source(ABNS)designed primarily for producing epithermal neutrons has been implemented in the treatment of brain tumors and other ... In the past decade,boron neutron capture therapy utilizing an accelerator-based neutron source(ABNS)designed primarily for producing epithermal neutrons has been implemented in the treatment of brain tumors and other cancers.The specifications for designing an epithermal beam are primarily based on the IAEA-TECODC-1223 report,issued in 2001 for reactor neutron sources.Based on this report,the latest perspectives and clinical requirements,we designed an ABNS capable of adjusting the average neutron beam energy.The design was based on a 2.8 MeV,20 mA proton beam bombarding a lithium target to produce neutrons that were subsequently moderated and tuned through a tunable beam shaping assembly(BSA)which can modify the thicknesses and materials of the coin-shaped moderators,back reflectors,filters,and collimators.The simulation results demonstrated that epithermal neutron beams for deep seated tumor treatment,which were generated by utilizing magnesium fluoride with lengths ranging between 28 and 36 cm as the moderator,possessed a treatment depth of 5.6 cm although the neutron flux peak shifts from 4.5 to 1.0 keV.When utilizing a thinner moderator,a less accelerated beam power can meet the treatment requirements.However,higher powers reduced the treatment time.In contrast,employing a thick moderator can reduce the skin dose.In scenarios that required relatively low energy neutron beams,the removal of the thermal neutron filter can raise the thermal neutron flux at the beam port.And the depth of the dose rate peak could be adjusted between 0.25 and 2.20 cm by combining magnesium fluoride and polyethylene coins of different thicknesses.Hence,this device has a better adaptability for the treatment of superficial tumors.Overall,the tunable BSA provides greater flexibility for clinical treatment than common BSA designs that can only adjust the port size. 展开更多
关键词 Boron neutron capture therapy(BNCT) Accelerator-based neutron source(ABNS) Beam shaping assembly(BSA) Treatment depth
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Integrated Virtual Assembly Process Planning System 被引量:5
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作者 LIU Jianhua HOU Weiwei SHANG Wei NING Ruxin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第5期717-728,共12页
Assembly process planning(APP) for complicated products is a time-consuming and difficult work with conventional method. Virtual assembly process planning(VAPP) provides engineers a new and efficiency way. Previou... Assembly process planning(APP) for complicated products is a time-consuming and difficult work with conventional method. Virtual assembly process planning(VAPP) provides engineers a new and efficiency way. Previous studies in VAPP are almost isolated and dispersive, and have not established a whole understanding and discussed key realization techniques of VAPP from a systemic and integrated view. The integrated virtual assembly process planning(IVAPP) system is a new virtual reality based engineering application, which offers engineers an efficient, intuitive, immersive and integrated method for assembly process planning in a virtual environment. Based on analysis the information integration requirement of VAPP, the architecture of IVAPP is proposed. Through the integrated structure, IVAPP system can realize information integration and workflow controlling. In order to mode/the assembly process in IVAPP, a hierarchical assembly task list(HATL) is presented, in which different assembly tasks for assembling different components are organized into a hierarchical list. A process-oriented automatic geometrical constraint recognition algorithm(AGCR) is proposed, so that geometrical constraints between components can be automatically recognized during the process of interactive assembling. At the same time, a progressive hierarchical reasoning(PHR) model is discussed. AGCR and PHR will greatly reduce the interactive workload. A discrete control node model(DCNM) for cable harness assembly planning in IVAPP is detailed. DCNM converts a cable harness into continuous flexed line segments connected by a series of section center points, and designs can realize cable harness planning through controlling those control nodes. Mechanical assemblies (such as transmission case and engine of automobile) are used to illustrate the feasibility of the proposed method and algorithms. The application of IVAPP system reveals advantages over the traditional assembly process planning method in shortening the time-consumed in assembly planning and in minimizing the handling difficulty, excessive reorientation and dissimilarity of assembly operations. 展开更多
关键词 virtual assembly assembly model assembly task collision detection automatic constraint recognition cable harness assembly process planning
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Application of Assembly Modeling and Simulation Technology to a Large Size Wind-drive Generator
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作者 WU Mei-ping ZHANG Qiu-ju 《International Journal of Plant Engineering and Management》 2009年第4期212-218,共7页
Challenges still remain in carrying out assembly modeling efficiently in virtual assembly (VA) fields. One of the root causes is the apparent weakness in effective description of assembly knowledge and information. ... Challenges still remain in carrying out assembly modeling efficiently in virtual assembly (VA) fields. One of the root causes is the apparent weakness in effective description of assembly knowledge and information. The assembly modeling, disassembly modeling, assembly interference inspection, assembly sequence planning and optimization, and assembly simulation display for key techniques is studied theoretically in this paper. An example of product assembly modeling is provided to illustrate the effectiveness of the proposed approach. On the basis of re- search, using assembly simulation techniques and multimedia techniques to finish structure design in linkage design of a large size wind-drive generator. The application of the modeling method has shortened the lead time dramatically. 展开更多
关键词 assembly simulation DMU (Digital Mock-Up) assembly modeling disassembly modeling assembly path optimization assembly sequence planning
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Assembly-oriented reliability analysis method for the top-connection structure of a nuclear fuel assembly
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作者 Ying-Dong Liu Wen-Qiang Li +2 位作者 Jia-Hao Chen Si-Tong Ling Chang-Fu Wan 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第6期155-170,共16页
The nuclear fuel assembly is the core component of a nuclear reactor.In a pressurized water reactor fuel assembly,the top-connection structure connects the top nozzle to the guide thimble.Its performance reliability i... The nuclear fuel assembly is the core component of a nuclear reactor.In a pressurized water reactor fuel assembly,the top-connection structure connects the top nozzle to the guide thimble.Its performance reliability is essential for the stability of the nuclear fuel assembly.In this study,an assembly-oriented reliability analysis method for top-connection structures is presented by establishing an assembly-oriented top-connection structure parameter modeling method and a nonlinear contact gap and penetration correction method.A reliability model of the top-connection assembly structure,including multiple stochastic design variables,was constructed,and the overall reliability of the top-connection assembly structure was obtained via a Kriging model and Monte Carlo simulation.The acquired experimental data were consistent with real-world failure conditions,which verified the practicability and feasibility of the reliability analysis method proposed in this study. 展开更多
关键词 assembly Top-connection structure Parametric model Approximation model Structural reliability
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Environmental and spatial contributions to tree community assembly across life stages and scales in evergreen-deciduous broadleaf karst forests,southwest China
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作者 Liang Su Hu Du +5 位作者 Fuping Zeng Wanxia Peng Hua Wang Kelin Wang Menzhen Lu Tongqing Song 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第5期1323-1331,共9页
Spatial and environmental processes are two ecological processes that have attracted considerable attention in plant community assembly,depending on sampling scale and life history.However,the processes that determine... Spatial and environmental processes are two ecological processes that have attracted considerable attention in plant community assembly,depending on sampling scale and life history.However,the processes that determine community assembly have not been studied in the karst region of southwest China.In this study,a 25-ha(500 m×500 m)monitoring plot within the subtropical climax forest in the karst region was established and canonical correspondence analysis was used to reveal the effects of topography and soil on the spatial patterns of tree community assembly.Our study suggests that spatial processes dominate species composition and the combined effects of spatial and environmental processes play an important role.Overall interpretation rate increases with enlarging the sampling scale.However,the pattern of variation partitioning was similar in different life stages.Environmental variables significantly affected species composition at different sampling sizes and life histories and had a higher interpretation rate of species composition on larger s ampling sizes.Topographic wetness index was the most important variable to explain species composition of the environmental variables.These results suggest that it is necessary to consider the relative importance of environmental and spatial factors on community assembly to better understand,conserve,and manage subtropical karst forests. 展开更多
关键词 Species composition Spatial distribution Variation partitioning Community assembly Karst ecosystems
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Temporal characteristics of algae-denitrifying bacteria co-occurrence patterns and denitrifier assembly in epiphytic biofilms on submerged macrophytes in Caohai Lake,SW China
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作者 Pinhua XIA Guoqing LI +3 位作者 Xianfei HUANG Lei SHI Xin DU Tao LIN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第6期2276-2291,共16页
Denitrifying bacteria in epiphytic biofilms play a crucial role in nitrogen cycle in aquatic habitats.However,little is known about the connection between algae and denitrifying bacteria and their assembly processes i... Denitrifying bacteria in epiphytic biofilms play a crucial role in nitrogen cycle in aquatic habitats.However,little is known about the connection between algae and denitrifying bacteria and their assembly processes in epiphytic biofilms.Epiphytic biofilms were collected from submerged macrophytes(Patamogeton lucens and Najas marina L.)in the Caohai Lake,Guizhou,SW China,from July to November 2020 to:(1)investigate the impact of abiotic and biotic variables on denitrifying bacterial communities;(2)investigate the temporal variation of the algae-denitrifying bacteria co-occurrence networks;and(3)determine the contribution of deterministic and stochastic processes to the formation of denitrifying bacterial communities.Abiotic and biotic factors influenced the variation in the denitrifying bacterial community,as shown in the Mantel test.The co-occurrence network analysis unveiled intricate interactions among algae to denitrifying bacteria.Denitrifying bacterial community co-occurrence network complexity(larger average degrees representing stronger network complexity)increased continuously from July to September and decreased in October before increasing in November.The co-occurrence network complexity of the algae and nirS-encoding denitrifying bacteria tended to increase from July to November.The co-occurrence network complexity of the algal and denitrifying bacterial communities was modified by ammonia nitrogen(NH_(4)^(+)-N)and total phosphorus(TP),pH,and water temperature(WT),according to the ordinary least-squares(OLS)model.The modified stochasticity ratio(MST)results reveal that deterministic selection dominated the assembly of denitrifying bacterial communities.The influence of environmental variables to denitrifying bacterial communities,as well as characteristics of algal-bacterial co-occurrence networks and the assembly process of denitrifying bacterial communities,were discovered in epiphytic biofilms in this study.The findings could aid in the appropriate understanding and use of epiphytic biofilms denitrification function,as well as the enhancement of water quality. 展开更多
关键词 denitrifying bacteria epiphytic biofilms co-occurrence networks submerged macrophytes community assembly
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