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Chinese Journal of Mechanical Engineering 2024年第4期37卷 290-305页

作者： Chao wang Tao Zhu bing Yang Shoune Xiao Guangwu Yang State Key Laboratory of Rail Transit Vehicle System Southwest Jiao tong UniversityChengdu 610031China

The current research on the integrity of critical structures of rail vehicles mainly focuses on the design stage,which needs an effective method for assessing the service *** paper proposes a framework for predicting the remaining useful life(RUL)of in-service structures with and without visible *** hypothetical distribution and delay time models were used to apply the equivalent crack growth life data of heavy-duty railway cast steel knuckles,which revealed the evolution characteristics of the crack length and life scores of the knuckle under different fracture failure *** results indicate that the method effectively predicts the RUL of service knuckles in different failure modes based on the cumulative failure probability curves for different locations and surface crack *** study proposes an RUL prediction framework that supports the dynamic overhaul and state maintenance of knuckle fatigue cracks.

关键词： Heavy-duty railway Cast steel knuckle Remaining useful life Fatigue crack growth Hypothetical distribution

Microplastics may reduce the fish bioaccumulation of organic pollutants

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Science China Technological Sciences 2024年第10期67卷 3079-3090页

作者： YANG bing ZHOU Xian HU XiaoJie QIN Chao wang Jian GAO YanZheng Institute of Organic Contaminant Control and Soil Remediation College of Resource and Environmental SciencesNanjing Agricultural University

Microplastics have frequently been regarded as a threat to aquatic organisms due to their potential to enhance the accessibility of organic pollutants. However, studies of microplastics as “carriers” in the process of bioaccumulation have only been conducted on a few organic contaminants. In this study, we employed machine learning algorithms to predict the sorption capacity of 83 exogenous organic pollutants(in CCL4) on microplastics, the prediction model exhibits exceptional predictive performance,achieving R2values of 0.8651 and 0.6962, RMSE values of 0.4625 and 0.1841 for the sorption coefficients Kfand n, respectively,and quantitatively estimated the contribution of microplastics to the bioaccumulation levels of organic pollutants in Gadus morhua. By considering both natural and microplastic-ingesting pathways, we demonstrated that the ingestion of microplastics containing organic pollutants facilitates the entry of organic pollutants into Gadus morhua. However, due to their robust sorption capacity, microplastics transport the organic pollutants accumulated through the natural pathway out of the fish, thereby preventing bioaccumulation. These findings elucidate the “cleaning” mechanism of microplastics concerning various organic pollutants in aquatic organisms, providing valuable insights for accurately assessing the risk of microplastics in aquatic environments.

关键词： microplastics aquatic organisms organic pollutants machine learning risks

Characteristics of proppant transport and placement within rough hydraulic fractures

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Petroleum Exploration and Development 2024年第2期51卷 453-463页

作者： HUANG Hai ZHENG Yong wang Yi wang Haizhu NI Jun wang Bin YANG bing ZHANG Wentong School of Petroleum Engineering Xi’an Shiyou UniversityXi’an 710065China Shaanxi Key Laboratory of Carbon Dioxide Sequestration and Enhanced Oil Recovery Xi’an 710075China Shaanxi Provincial Key Laboratory of Oil and Gas Well and Reservoir Seepage and Rock Mechanics Xi’an 710065China Oil&Gas Field Production Construction Division PetroChina Tarim Oilfield CompanyKorla 841000China National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing 102249China Shaanxi Yanchang Petroleum(Group)Co. Ltd.Xi’an 710075China

A three-dimensional reconstruction of rough fracture surfaces of hydraulically fractured rock outcrops is carried out by casting process,a large-scale experimental setup for visualizing rough fractures is built to perform proppant transport *** typical characteristics of proppant transport and placement in rough fractures and its intrinsic mechanisms are investigated,and the influences of fracture inclination,fracture width and fracturing fluid viscosity on proppant transport and placement in rough fractures are *** results show that the rough fractures cause variations in the shape of the flow channel and the fluid flow pattern,resulting in the bridging buildup during proppant transport to form unfilled zone,the emergence of multiple complex flow patterns such as channeling,reverse flow and bypassing of sand-carrying fluid,and the influence on the stability of the sand *** proppant has a higher placement rate in inclined rough fractures,with a maximum increase of 22.16 percentage points in the experiments compared to vertical fractures,but exhibits poor stability of the sand *** fracture width aggravates the bridging of proppant and induces higher pumping *** the viscosity of the fracturing fluid can weaken the proppant bridging phenomenon caused by the rough fractures.

关键词： reservoir fracturing rough fracture proppant transport and placement characteristics bridging buildup

Research progress on the effect of pyroptosis on the occurrence,development,invasion and metastasis of colorectal cancer

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3410-3427页

作者： Xu wang Qi-Hang Yin Lin-Lu Wan ruo-Lan Sun Gang wang Jun-Fei Gu De-Cai Tang School of Traditional Chinese Medicine Nanjing University of Chinese MedicineNanjing 210023Jiangsu ProvinceChina Department of Ana and Intestine Surgery The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina

Pyroptosis is a type of programmed cell death mediated by gasdermines(GSDMs).The N-terminal domain of GSDMs forms pores in the plasma membrane,causing cell membrane rupture and the release of cell contents,leading to an inflammatory response and mediating *** plays an important role in inflammatory diseases and malignant *** the further study of pyroptosis,an increasing number of studies have shown that the pyroptosis pathway can regulate the tumor microenvironment and antitumor immunity of colorectal cancer and is closely related to the occurrence,development,treatment and prognosis of colorectal *** review aimed to explore the molecular mechanism of pyroptosis and the role of pyroptosis in the occurrence,development,treatment and prognosis of colorectal cancer(CRC)and to provide ideas for the clinical diagnosis and treatment of CRC.

关键词： Cell pyroptosis Tumor metastasis Colorectal cancer Clinical diagnosis Review

A Hybrid Approach for Predicting the Remaining Useful Life of Bearings Based on the RReliefF Algorithm and Extreme Learning Machine

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1405-1427页

作者： Sen-Hui wang Xi Kang Cheng wang Tian-bing Ma Xiang He Ke Yang School of Mechatronics Engineering Anhui University of Science and TechnologyHuainan232001China Institute of Energy Hefei Comprehensive National Science CenterHefei230031China

Accurately predicting the remaining useful life(RUL)of bearings in mining rotating equipment is vital for mining *** research aims to distinguish the features associated with the RUL of bearings and propose a prediction model based on these selected *** study proposes a hybrid predictive model to assess the RUL of rolling element *** proposed model begins with the pre-processing of bearing vibration signals to reconstruct sixty time-domain *** hybrid model selects relevant features from the sixty time-domain features of the vibration signal by adopting the RReliefF feature selection ***,the extreme learning machine(ELM)approach is applied to develop a predictive model of RUL based on the optimal *** model is trained by optimizing its parameters via the grid search *** training datasets are adjusted to make them most suitable for the regression model using the cross-validation *** proposed hybrid model is analyzed and validated using the vibration data taken from the public XJTU-SY rolling element-bearing *** comparison is constructed with other traditional *** experimental test results demonstrated that the proposed approach can predict the RUL of bearings with a reliable degree of accuracy.

关键词： Bearing degradation remaining useful life estimation RReliefF feature selection extreme learning machine

Flexible,efficient,and accurate tests for epidemics

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Science China Mathematics 2024年第8期67卷 1881-1898页

作者： Linjiajie Fang bing-Yi Jing Shen Ling Qiyue wang Qing Yang Data Science and Analytics Thrust The Hong Kong University of Science and TechnologyHong KongChina Department of Statistics and Data Science Southern University of Science and TechnologyShenzhen 518055China Department of Mathematics and Statistics Dalhousie UniversityHalifaxNS B 3H 4R 2Canada Department of Mathematics The Hong Kong University of Science and TechnologyHong KongChina

Group testing involves discovering a small subset of distinguished subjects from a large population while efficiently reducing the total number of *** has been widely used for industrial testing,information technology,and biology,especially epidemic ***,in reality,are noisy for the presence of false *** tests are accurate but time-consuming,while others are cheaper but less *** which test to use is constrained by various considerations,such as availability,cost,accuracy,and *** this paper,we propose flexible,efficient,and accurate tests(FEATs).FEATs are based on group testing with simple but careful designs by incorporating ideas such as close contact cliques and repeated *** could dramatically improve the efficiency or accuracy of existing *** example,for accurate but slow tests,the FEAT can improve efficiency multiple times without compromising *** the other hand,for fast but inaccurate tests,the FEAT can sharply reduce the false-negative rate(FNR)and significantly increase *** justifications are *** point out some scenarios where the FEAT can be effectively employed.

关键词： epidemiology control blood testing testing efficiency testing accuracy

Polymer-on-HOF:a new strategy for fabricating“armour-plated”HOFs to sequester radioactive anions

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Science China Chemistry 2024年第9期67卷 2958-2967页

作者： Hai-ruo Li Shitao Wu Xuezhuo Jing Zhengyi Di Kun Liu Lu wang Cheng-Peng Li Zhong Liu Miao Du College of Chemistry Tianjin Key Laboratory of Structure and Performance for Functional MoleculesTianjin Normal UniversityTianjin 300387China Shanghai Key Laboratory of High-Resolution Electron Microscopy School of Physical Science and TechnologyShanghaiTech UniversityShanghai 201210China Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources Qinghai Provincial Key Laboratory of Resources and Chemistry of Salt LakesQinghai Institute of Salt LakesChinese Academy of SciencesXining 810008China College of Material and Chemical Engineering Institute of New Energy Science and TechnologySchool of Future Hydrogen Energy TechnologyZhengzhou University of Light IndustryZhengzhou 450001China

The development of hydrogen-bonded organic frameworks(HOFs)faces significant constraints,primarily attributed to their fragile architectures and limited functionalization *** overcome these limitations,this work presents a new polymeron-HOF strategy by covalently tethering armor-like polymers onto the surface of *** application of this approach not only bolsters the stability of HOFs,but also facilitates the customization of their functional expansion in radionuclide *** optimized HOF-polymer materials display extraordinary ability in radionuclide sequestration,achieving uptake of I^(-)(0.699 g g^(-1)),IO_(3)^(-)(0.285 g g^(-1))and ReO_(4)^(-)(1.616 g g^(-1),setting a world record),fast adsorption kinetics(~100% removal within 45 s),and exceptional regeneration capability(>30 cycles)under continuous flow *** outstanding performances benefit from the internal porous channels and surface imidazolium polymer coatings of HOFs,as proved by density functional theory calculation and molecular dynamics *** work paves the way for the rational design of HOF-based hybrid materials tailored to versatile applications.

关键词： hydrogen-bonded organic frameworks(HOFs) post-synthetic modification radionuclide sequestration

Tunable Phase Structure of Side-chain Liquid Crystalline Polymers Enabled by Molecular Engineering of Dual Mesogenic Cores

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Chinese Journal of Polymer Science 2024年第10期42卷 1459-1469,I0009页

作者： Wen-Huan Yao Lan-Sheng Liu Jie Zhao Yan-Xia wang An-Zhi Ma Zheng-Rui Ma Lan-Ying Zhang ruo-Chen Lan College of Chemistry and Chemical Engineering Hunan UniversityChangsha410082China Key Laboratory of Eco-Functional Polymer Materials of the Ministry of Education Key Laboratory of Eco-Environmental Polymer Materials of Gansu ProvinceCollege of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhou730070China Department of Materials Science and Engineering College of EngineeringPeking UniversityBeijing100871China Institute of Advanced Materials&Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education College of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchang330022China

A series of novel side-chain liquid crystalline(SCLC)copolymers were synthesized by attaching two distinct mesogenic units,namely a chiral cholesteryl-based monomer(M1)and an achiral biphenyl-based monomer(M2),to a poly(3-mercaptopropylmethylsiloxane)(PMMS)backbone via thiol-ene click *** influence of side chain composition on the self-assembly behavior and phase structures of these SCLC copolymers was systematically investigated using different *** indicate that three distinct liquid crystalline phases and four unique molecular configurations were identified within the polymer series,with the emergence of the liquid crystalline phase being a synergistic outcome of the two distinct side *** study underscores the critical influence of side chain dimensions,rigidity,and spatial volume on the self-assembly structures and phase characteristics of liquid crystalline polymers,providing valuable insights for the rational design and development of advanced functional materials with tailored properties.

关键词： Liquid crystalline copolymers Self-assembly Phase structure Chiral molar ratio

Bionic lightweight design of limb leg units for hydraulic quadruped robots by additive manufacturing and topology optimization

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Bio-Design and Manufacturing 2024年第1期7卷 1-13页

作者： Huaizhi Zong Junhui Zhang Lei Jiang Kun Zhang Jun Shen Zhenyu Lu Ke wang Yanli wang bing Xu The State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310058China Unmanned Vehicle Research and Development Center China North Vehicle Research InstituteBeijing 100072China School of Mechatronic Engineering Nanchang UniversityNanchang 330031China Auclean High-Tech Ltd. Wuxi 214108China

Galloping cheetahs,climbing mountain goats,and load hauling horses all show desirable locomotion capability,which motivates the development of quadruped *** various quadruped robots,hydraulically driven quadruped robots show great potential in unstructured environments due to their discrete landing positions and large *** the most critical movement unit of a quadruped robot,the limb leg unit(LLU)directly affects movement speed and reliability,and requires a compact and lightweight *** by the dexterous skeleton–muscle systems of cheetahs and humans,this paper proposes a highly integrated bionic actuator system for a better dynamic performance of an *** propose that a cylinder barrel with multiple element interfaces and internal smooth channels is realized using metal additive manufacturing,and hybrid lattice structures are introduced into the lightweight design of the piston *** addition,additive manufacturing and topology optimization are incorporated to reduce the redundant material of the structural parts of the *** mechanical properties of the actuator system are verified by numerical simulation and experiments,and the power density of the actuators is far greater than that of cheetah *** mass of the optimized LLU is reduced by 24.5%,and the optimized LLU shows better response time performance when given a step signal,and presents a good trajectory tracking ability with the increase in motion frequency.

关键词： Additive manufacturing Bionic lightweight design Limb leg unit Quadruped robot Trajectory tracking

Ultra reliability and massive connectivity provision in integrated internet of military things(IoMT)based on tactical datalink

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Defence Technology（防务技术） 2024年第3期33卷 386-398页

作者： Li bing Yating Gu Lanke Hu Li Bowen Yang Lihua Jue wang Yue Yin Northwestern Polytechnical University Xi'an 710072China China Academy of Information and Communications Technology Beijing 100191China China Intelligent and Connected Vehicles(Beijing)Research Institute Co. LtdBeijing 100176China The 20th Research Institute of China Electronic Technology Group Corporation Xi’an 710068China Xidian University Xi'an 710071China

One of the major challenges arising in internet of military things(IoMT)is accommodating massive connectivity while providing guaranteed quality of service(QoS)in terms of ultra-high *** this regard,this paper presents a class of code-domain nonorthogonal multiple accesses(NOMAs)for uplink ultra reliable networking of massive IoMT based on tactical datalink such as Link-16 and joint tactical information distribution system(JTIDS).In the considered scenario,a satellite equipped with Nr antennas servers K devices including vehicles,drones,ships,sensors,handset radios,*** coded modulation,a special form of multiple input multiple output(MIMO)-NOMA is *** discussion starts with evaluating the output signal to interference-plus-noise(SINR)of receiver filter,leading to the unveiling of a closed-form expression for overloading systems as the number of users is significantly larger than the number of devices admitted such that massive connectivity is *** expression allows for the development of simple yet successful interference suppression based on power allocation and phase shaping techniques that maximizes the sum rate since it is equivalent to fixed-point programming as can be *** proposed design is exemplified by nonlinear modulation schemes such as minimum shift keying(MSK)and Gaussian MSK(GMSK),two pivotal modulation formats in IoMT standards such as Link-16 and *** results show that near capacity performance is ***,the performance is obtained using simple forward error corrections(FECs)of higher coding rate than existing schemes do,while the transmit power is reduced by 6 *** proposed design finds wide applications not only in IoMT but also in deep space communications,where ultra reliability and massive connectivity is a keen concern.

关键词： Satellite network Deep space communications Internet of military things Non-orthogonal multiple access MIMO Link-16 JITDS