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Application of surfactant for improving leaching process of weathered crust elution-deposited rare earth ores

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Journal of Rare Earths 2024年第1期42卷 181-190,I0007页

作者： Fang Zhou Lisen Zhang Zhiwei Wang Yixin Zhang Ru'an chi Xiaoyan wu Key Laboratory for Green Chemical Process of Ministry of Education Wuhan Institute of TechnologyWuhan430073China

Weathered crust elution-deposited rare earth ores(WREOs)in china are the main source of medium and heavy rare earths in the *** order to improve the seepage and the mass transfer of traditional ammonium salt leaching process of WREOs,surfactants were added in the ammonium sulfate leaching solution and the ammonium chloride leaching *** leaching kinetics,the mass transfer process,and the adhesion work reduction factor calculated from the interfacial properties were studied to reveal the strengthening mechanism of *** the presence of the tested five surfactants,cetyl trimethyl ammonium bromide(CTAB),dodecyl trimethyl ammonium bromide(DTAB),sodium dodecyl sulfate(SDS),sodium oleate and oleic acid,the permeability of WREOs is improved,the rare earth(RE)leaching efficiency increase and the impurity aluminum(Al)leaching efficiency decrease,indicating its promotional effect on the leaching process of ***,CTAB shows a better leaching enhancement,and the optimal addition dosage is 0.4 g/L for the two ammonium salt leaching agent *** kinetics analysis shows the internal diffusion controls model of RE and Al leaching process,and the leaching kinetics equations of RE and Al related to CTAB concentration were obtained for the two ammonium salt leaching *** to the chromatographic plate theory,the mass transfer efficiency of RE increases with the CTAB concentration increasing until 0.4 g/L,which confirms that the optimal CTAB addition is 0.4 g/*** adhesion work and adhesion work reduction factor indicate more favorable permeation as well as the leaching process.

关键词： Weathered crust elution-deposited rare earth ores Surfactant Kinetics Mass transfer

An Underwater Biomimetic Robot that can Swim,Bipedal Walk and Grasp

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Journal of Bionic Engineering 2024年第3期21卷 1223-1237页

作者： Qiuxuan wu Liwei Pan FuLin Du ZhaoSheng wu XiaoNi chi FaRong Gao Jian Wang Anton A.Zhilenkov School of Automation Hangzhou Dianzi UniversityHangzhou310018China International Joint Research Laboratory for Autonomous Robotic Systems Hangzhou310018China GEELY Automotive Institute Hangzhou Vocational and Technical CollegeHangzhou310018China Institute of Hydrodynamics and Control Processes Sankt-Petersburg Saint Petersburg State Marine Technical UniversitySankt-PetersburgRussia

In developing and exploring extreme and harsh underwater environments,underwater robots can effectively replace humans to complete *** meet the requirements of underwater flexible motion and comprehensive subsea operation,a novel octopus-inspired robot with eight soft limbs was designed and *** robot possesses the capabilities of underwater bipedal walking,multi-arm swimming,and grasping *** closely interact with the underwater seabed environment and minimize disturbance,the robot employs a cable-driven flexible arm for its walking in underwater floor through a bipedal walking *** multi-arm swimming offers a means of three-dimensional spatial movement,allowing the robot to swiftly explore and navigate over large areas,thereby enhancing its ***,the robot’s walking arm enables it to grasp and transport objects underwater,thereby enhancing its practicality in underwater environments.A simplified motion models and gait generation strategies were proposed for two modes of robot locomotion:swimming and walking,inspired by the movement characteristics of octopus-inspired multi-arm swimming and bipedal *** experimental verification,the robot’s average speed of underwater bipedal walking reaches 7.26 cm/s,while the horizontal movement speed for multi-arm swimming is 8.6 cm/s.

关键词： Underwater soft robots Underwater bipedal walking Multi-arm swimming Cable drive

A stable one-point quadrature rule for three-dimensional numerical manifold method

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Science china(Technological Sciences) 2024年第5期67卷 1401-1416页

作者： ZHANG Ning ZHENG Hong YANG Liang wu WenAn YUAN chi School of Civil Engineering Qinghai UniversityQinghai810016China Key Laboratory of Urban Security and Disaster Engineering Ministry of EducationBeijing University of TechnologyBeijing100124China Faculty of Engineering China University of GeoscienceWuhan430074China

We present a numerically stable one-point quadrature rule for the stiffness matrix and mass matrix of the three-dimensional numerical manifold method(3D NMM).The rule simplifies the integration over irregularly shaped manifold elements and overcomes locking issues,and it does not cause spurious modes in modal *** essential idea is to transfer the integral over a manifold element to a few moments to the element center,thereby deriving a one-point integration rule by the moments and making modifications to avoid locking *** the stiffness matrix,after the virtual work is decomposed into moments,higher-order moments are modified to overcome locking issues in nearly incompressible and bending-dominated *** the mass matrix,the consistent and lumped types are derived by *** particular,the lumped type has the clear advantage of *** proposed method is naturally suitable for 3D NMM meshes automatically generated from a regular *** tests justify the accuracy improvements and the stability of the proposed procedure.

关键词： three-dimensional numerical manifold method quadrature rule locking mass lumping

Regulating the crystal phase of bismuth-based semiconductors for promoted photocatalytic performance

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Science china Chemistry 2024年第6期67卷 1839-1864页

作者： Zhaohui wu Mei-chi Chong Shiying Zhang Junshan Li Yongfa Zhu Hunan Key Laboratory of Applied Environmental Photocatalysis Changsha UniversityChangsha410022China Department of Chemistry Tsinghua UniversityBeijing100084China Institute for Advanced Study Chengdu UniversityChengdu610106China

Numerous bismuth-based semiconductors(BBSs)with sophisticated and desirable structures used as photocatalysts for efficient photocatalytic degradation of water organic contaminants have attracted considerable ***,regulating the crystal phases and phase transition of BBSs for promoted photocatalytic performance is ***,the unique crystal structure and band structure features of each typical BBSs,and the vital roles on phase controlling of each phase were systematically presented based on the classification of ***,the critical factors for the phase transition of BBSs and intrinsic driving forces endowed by phases of BBSs for enhanced photocatalytic performance of organic contaminants removal were also *** review will provide systematical guidelines and horizons for regulating the crystal phase and phase transition of BBSs,promoting photocatalytic degradation and mineralization of organic contaminants.

关键词： bismuth-based semiconductors phase regulation photocatalytic performances organic contaminants

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Electrical discharge and arc milling with automatic tracking of optimal flushing direction:A novel high-efficiency compound machining method

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chinese Journal of Aeronautics 2024年第3期37卷 351-364页

作者： Xinlei wu Yonghong LIU Pengxin ZHANG Liang QI Dege LI chi MA Renjie JI College of Mechanical and Electronic Engineering China University of Petroleum(East China)Qingdao 266580China School of Mechanical and Power Engineering Nanjing Tech UniversityNanjing 211816China

The arc milling method has the advantages of high machining efficiency and low cost and is independent of the strength and hardness of machined ***,frequent electrode back-offs and the risk of workpiece burning may occur if erosion products are not removed *** this study,it was found that the flushing method of the working medium had a significant impact on the machining performance of arc *** on this,a novel highefficiency compound machining method of electrical discharge and arc milling with automatic tracking of the optimal flushing direction was *** automatic tracking optimizer for external working medium injection was designed to determine the optimal external flushing direction according to the feed *** influence of flushing methods,working mediums,and machining parameters on the machining efficiency,tool electrode wear rate,machining error,and surface integrity of titanium alloys were *** results indicated that better machining performance and environmental friendliness were achieved using the compound flushing method of outer compressed air and inner deionized ***,the automatic tracking flushing method in the opposite direction of the feed direction showed superior results compared to other *** material removal rate with the opposite direction injection could be increased up to 1.62 times that of the same direction,and the relative electrode wear rate could be reduced by 14.76%.This novel method has broad application prospects for machining parts with difficult-to-cut materials in aerospace and military industries.

关键词： Arc milling Dielectric Difficult-to-cut materials Electric discharge machining Erosion Material removal rate

A data-driven approach to RUL prediction of tools

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Advances in Manufacturing 2024年第1期12卷 6-18页

作者： Wei Li Liang-chi Zhang Chu-Han wu Yan Wang Zhen-Xiang Cui Chao Niu Department of Mechanical Engineering University College LondonLondonWC1E 7JEUK Shenzhen Key Laboratory of Cross-Scale Manufacturing Mechanics Southern University of Science and TechnologyShenzhen518055GuangdongPeople’s Republic of China SUSTech Institute for Manufacturing Innovation Southern University of Science and TechnologyShenzhen518055GuangdongPeople’s Republic of China Department of Mechanics and Aerospace Engineering Southern University of Science and TechnologyShenzhen518055GuangdongPeople’s Republic of China School of Mechanical and Manufacturing Engineering The University of New South WalesKensingtonNSW2052Australia Baoshan Iron&Steel Co. Ltd.Shanghai200941People’s Republic of China

An effective and reliable prediction of the remaining useful life(RUL)of a tool is important to a metal forming process because it can significantly reduce unexpected maintenance,avoid machine shutdowns and increase system *** study proposes a new data-driven approach to the RUL prediction for metal forming processes under multiple contact sliding *** data-driven approach took advantage of bidirectional long short-term memory(BLSTM)and convolutional neural networks(CNN).A pre-trained lightweight CNN-based network,WearNet,was re-trained to classify the wear states of workpiece surfaces with a high accuracy,then the classification results were passed into a BLSTM-based regression model as inputs for RUL *** experimental results demonstrated that this approach was able to predict the RUL values with a small error(below 5%)and a low root mean square error(RMSE)(around 1.5),which was more superior and robust than the other state-of-the-art methods.

关键词： Remaining useful life(RUL) Bidirectional long short-term memory(BLSTM) Data-driven approach Metal forming

SGT-Net: A Transformer-Based Stratified Graph Convolutional Network for 3D Point Cloud Semantic Segmentation

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Computers, Materials & Continua 2024年第6期79卷 4471-4489页

作者： Suyi Liu Jianning chi Chengdong wu Fang Xu Xiaosheng Yu Faculty of Robot Science and Engineering Northeastern UniversityShenyang110167China State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang110016China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang110169China SIASUN Robot&Automation Co. Ltd.Shenyang110169China

In recent years,semantic segmentation on 3D point cloud data has attracted much *** 2D images where pixels distribute regularly in the image domain,3D point clouds in non-Euclidean space are irregular and inherently ***,it is very difficult to extract long-range contexts and effectively aggregate local features for semantic segmentation in 3D point cloud *** current methods either focus on local feature aggregation or long-range context dependency,but fail to directly establish a global-local feature extractor to complete the point cloud semantic segmentation *** this paper,we propose a Transformer-based stratified graph convolutional network(SGT-Net),which enlarges the effective receptive field and builds direct long-range ***,we first propose a novel dense-sparse sampling strategy that provides dense local vertices and sparse long-distance vertices for subsequent graph convolutional network(GCN).Secondly,we propose a multi-key self-attention mechanism based on the Transformer to further weight augmentation for crucial neighboring relationships and enlarge the effective receptive *** addition,to further improve the efficiency of the network,we propose a similarity measurement module to determine whether the neighborhood near the center point is *** demonstrate the validity and superiority of our method on the S3DIS and ShapeNet *** ablation experiments and segmentation visualization,we verify that the SGT model can improve the performance of the point cloud semantic segmentation.

关键词： 3D point cloud semantic segmentation long-range contexts global-local feature graph convolutional network dense-sparse sampling strategy

The modulatory effect of oolong tea polyphenols on intestinal flora and hypothalamus gene expression in a circadian rhythm disturbance mouse model

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Food Science and Human Wellness 2024年第2期13卷 748-764页

作者： Ruonan Yan chi-Tang Ho Yanan Liu Shengnan Zhan Zufang wu Xin Zhang Department of Food Science and Engineering Ningbo UniversityNingbo 315211China Department of Food Science Rutgers UniversityNew BrunswickNew Jersey 08901USA

The interaction between host circadian rhythm and gut microbes through the gut-brain axis provides new clues for tea polyphenols to improve host *** present research showed that oolong tea polyphenols(OTP)improved the structural disorder of the intestinal flora caused by continuous darkness,thereby modulating the production of metabolites related to pyruvate metabolism,glycolysis/gluconeogenesis,and tryptophan metabolism to alleviate the steady-state *** fecal microbiota transplantation from the OTP group,the single-cell transcriptomic analysis revealed that OTP significantly increased the number of hypothalamus cell clusters,up-regulated the number of astrocytes and fibroblasts,and enhanced the expression of circadian rhythm genes Cry2,Per3,Bhlhe41,Nr1d1,Nr1d2,Dbp and Rorb in hypothalamic *** results confirmed that OTP can actively improve the intestinal environmental state as well as internal/peripheral circadian rhythm disorders and cognitive impairment,with potential prebiotic functional characteristics to notably contribute to host health.

关键词： Gut microbiota Circadian rhythm Oolong tea polyphenols Single-cell sequencing Metabolism

High-performance Bi_(2)S_(3)/ZnO photoanode enabled by interfacial engineering with oxyanion for efficient photoelectrochemical water oxidation

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Nano Research 2024年第7期17卷 5996-6005页

作者： Ying-Chu Chen hsiang-Yu Jui Yichen Feng Yun-hsiang Lu Yu-Kuei Hsu Department of Chemical Engineering&Biotechnology "National Taipei University of Technology"No.1Sec.3Zhong-Xiao E.Rd.Da'an Dist.Taipei City 10608TaiwanChina Department of Opto-Electronic Engineering "National Dong Hwa University"No.1Sec.2Da Hsueh RoadShoufengHualien 97401TaiwanChina china-UK Low Carbon College Shanghai Jiao Tong UniversityNo.3Yinlian RoadLingangShanghai 201306China

In the present contribution,we demonstrate that the sluggish kinetics of oxygen evolution reaction(OER)over the bismuth sulfide(Bi_(2)S_(3))photoanode,which severely restricts its photoelectrochemical activity,is markedly accelerated by employing a sulfatecontaining ***-principle calculation points to the spontaneous adsorption of sulfate(SO_(4)^(2−))on Bi_(2)S_(3)and its capacity of stabilizing the OER intermediates through hydrogen bonding,which is further reinforced by increasing the local density of states near the Fermi level of Bi_(2)S_(3).Meanwhile,the electron transfer is also promoted to synergistically render the ratedetermining step(from O*to OOH*)of OER over Bi_(2)S_(3)kinetically *** but not least,benefitting from such enhanced OER activity and efficient charge separation resulted from depositing Bi_(2)S_(3)on the zinc oxide nanorods(ZnO NRs),forming a core–shell heterojunction,its photocurrent density achieves 8.61 mA·cm^(−2)at 1.23 VRHE,far surpassing those reported for additional Bi_(2)S_(3)-based and several state-of-the-art photoanodes in the literature and further exceeding their theoretical *** great promise of the Bi_(2)S_(3)/ZnO NRs is in view of such outperformance,the superior Faradaic yield of oxygen of more than~80%and the outstanding half-cell applied bias photon-to-current efficiency of~1%well corroborated.

关键词： photoelectrochemical water oxidation oxyanion adsorption electronic structure regulation oxygen evolution reaction(OER)intermediates stabilization Bi_(2)S_(3)