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Geometric Error Identification of Gantry-Type CNC Machine Tool Based on Multi-Station Synchronization Laser Tracers

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 150-162页

作者： Jun zha.Huijie zha.g School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China Xi’an Jiaotong University Suzhou Academy Suzhou 215123China

Laser tracers are a three-dimensional coordinate measurement system that are widely used in industrial *** propose a geometric error identification method based on multi-station synchronization laser tracers to enable the rapid and high-precision measurement of geometric errors for gantry-type computer numerical control(CNC)machine *** method also improves on the existing measurement efficiency issues in the single-base station measurement method and multi-base station time-sharing measurement *** consider a three-axis gantry-type CNC machine tool,and the geometric error mathematical model is derived and established based on the combination of screw theory and a topological analysis of the machine kinematic *** four-station laser tracers position and measurement points are realized based on the multi-point positioning principle.A self-calibration algorithm is proposed for the coordinate calibration process of a laser tracer using the Levenberg-Marquardt nonlinear least squares method,and the geometric error is solved using Taylor’s first-order linearization *** experimental results show that the geometric error calculated based on this modeling method is comparable to the results from the Etalon laser *** a volume of 800 mm×1000 mm×350 mm,the maximum differences of the linear,angular,and spatial position errors were 2.0μm,2.7μrad,and 12.0μm,respectively,which verifies the accuracy of the proposed *** research proposes a modeling method for the precise measurement of errors in machine tools,and the applied nature of this study also makes it relevant both to researchers and those in the industrial sector.

关键词： Multi-point positioning Multi-station synchronization CNC machine tool Geometric error Error separation

Polydopamine-modified metal-organic frameworks nanoparticles enhance the corrosion resistance and bioactivity of polycaprolactone coating on high-purity magnesium

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Journal of Magnesium and Alloys 2024年第5期12卷 2070-2089页

作者： Qingyun Fu Shaojie He Junjie Yang Ziyu Su ping Li Xincheng Yu Weihong Jin Shulan Xu Zhentao Yu Dingsheng zha Center of Oral Implantology Stomatological HospitalSouthern Medical UniversityGuangzhouChina Panyu Hospital of Chinese Medicine Guangzhou 511400China Institute of Advanced Wear&Corrosion Resistant and Functional Materials Jinan UniversityGuangzhou 510632China First Affiliated Hospital of Jinan University Guangzhou 510630China

Biodegradable magnesium(Mg)and its alloys exhibit excellent biocompatibility and mechanical compatibility,demonstrating tremendous potential for applications in ***,the rapid degradation rate has limited their clinical ***(PCL)is commonly employed as a polymer coating to impede the rapid degradation of ***,its long-term anti-corrosion capability and bioactivity are *** address these issues,polydopamine(PDA)-modified zeolitic imidazolate framework-8(PZIF-8)bioactive nanoparticles are fabricated and incorporated into the PCL *** PZIF-8 particles,featuring catechol motifs,can enhance the compactness of the PCL coating,reduce its defects,and possess biomineralization ability,thereby effectively improving its anti-corrosive and bioactive ***,the active substances released from the degradation of the PZIF-8 particles such as Zn^(2+)and PDA are beneficial for *** corrosion tests indicate that the corrosion current density of PCL-treated sample decreases by more than one order of magnitude and the amount of H_(2)released decreases from 0.23±0.12 to 0.08±0.08 ml cm^(-2)after doping with the ***,the improved corrosion resistance and released PDA and Zn^(2+)from the coating can promote osteogenic differentiation by up-regulating the expression of alkaline phosphatase activity,related osteogenic genes,and *** addition,in vivo implantation experiments in rabbit femur defects further offer strong evidence that the doping of PZIF-8 nanoparticles accelerates bone reconstruction of the PCL *** summary,this work implies a new strategy to fabricate a PCL-based coating on Mg-based implants by introducing the PZIF-8 particles for orthopedic applications.

关键词： Polydopamine ZIF-8 High-purity magnesium Polycaprolactone coating Anticorrosion Bone regeneration

A solubility limited pyrene-4,5,9,10-tetraone-based covalent organic framework for high-performance aqueous zinc-organic batteries

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Nano Research 2024年第6期17卷 5095-5103页

作者： min Cheng Shibing Zheng Tianjiang Sun Diantao Li Weijia zha.g Zhengtai zha.Qiong Sun Jing Tian Kai zha.g zha.liang Tao Frontiers Science Center for New Organic Matter State Key Laboratory of Advanced Chemical Power SourcesKey Laboratory of Advanced Energy Materials Chemistry(Ministry of Education)Collaborative Innovation Center of Chemical Science and Engineering(Tianjin)Renewable Energy Conversion and Storage CentreNankai UniversityTianjin 300071China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

Pyrene-4,5,9,10-tetraone(PTO),with a high theoretical capacity of 408 mAh·g^(−1),is a promising candidate for rechargeable aqueous zinc-ion batteries(RAZIBs),but its zincated products during discharge process suffer from high solubility in ***,aβ-ketoenamine-linked two-dimensional(2D)covalent organic framework(COF)based on a 2,7-diaminopyrene-4,5,9,10-tetraone(4KT-BD)monomer and a 2,4,6-trihydroxy-benzene-1,3,5-tricarbaldehyde(Tp)node(4KT-Tp-COF)is synthesized to address the above *** well-designed 4KT-Tp-COF displays low solubility in 3 M Zn(CF3SO3)2 owing to the favorableπ-πstacking as well as extended ***,the ingenious structural design of the active molecule and the long-range ordered nano-channels alter the intramolecular electron distribution,which facilitates the ionic ***,the 4KT-Tp-COF cathode exhibits a stable capacity of 181 mAh·g^(−1)at 0.2 A·g^(−1),superior rate capability of 139 mAh·g^(−1)at 20 A·g^(−1),and a long lifetime of 1000 cycles without capacity loss at 30 A·g^(−1).Even at a low temperature of−20°C,the electrode also performs an ultralong cycling life of 9000 cycles with a capacity of 106 mAh·g^(−1)at 5 A·g^(−1).The comprehensive characterizations of ex-situ analyses together with the theoretical calculations validate that the groups of C=O can contribute highly accessible redox-active sites for Zn^(2+)*** ultra-stable 4KT-Tp-COF cathode provides important insights for designing robust organic electrodes for sustainable and large-scale electrochemical energy storage.

关键词： pyrene-4,5,9,10-tetraone solubility limited covalent organic framework zinc batteries

Molecular Dynamics-Based Simulation of Polyethylene Pipe Degradation in High Temperature and High Pressure Conditions

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Fluid Dynamics & Materials Processing 2024年第9期20卷 2139-2161页

作者： Guowei Feng Qing Li Yang Wang Nan Lin Sixi zha.Hang Dong ping Chen minjun Zheng School of Mechanical Engineering Xinjiang UniversityUrumqi830046China Xinjiang Yian Special Inspection Engineering Company Limited Urumqi830063China Xinjiang Uygur Autonomous Region Inspection Institute of Special Equipment Urumqi830000China Pressure Pipe Department China Special Equipment Inspection and Research InstituteBeijing100013China Tarim Oilfield Branch Company Korla841000China Yimai Cai Oil and Gas Management Area Tarim Oilfield Branch OfficeKorla841000China

High-density polyethylene(HDPE)pipes have gradually become the first choice for gas networks because of their excellent *** the use of pipes increases,there will unavoidably be a significant amount of waste generated when the pipes cease their operation life,which,if improperly handled,might result in major environmental contamination *** this study,the thermal degradation of polyethylene materials is simulated for different pressures(10,50,100,and 150 MPa)and temperatures(2300,2500,2700,and 2900 K)in the framework of Reactive Force Field(ReaxFF)molecular dynamics *** main gas products,density,energy,and the mean square displacement with temperature and pressure are also *** findings indicate that raising the temperature leads to an increase in the production of gas products,while changing the pressure has an impact on the direction in which the products are generated;the faster the temperature drops,the less dense the air;both temperature and pressure increase impact the system’s energy conversion or distribution mechanism,changing the system’s potential energy as well as its total energy;the rate at which molecules diffuse increases with temperature,and decreases with *** results of this investigation provide a theoretical basis for the development of the pyrolytic treatment of polyethylene waste materials.

关键词： ReaxFF MD high-density polyethylene degradation temperature pressure

Identification of the Hammerstein nonlinear system with noisy output measurements

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Control Theory and Technology 2024年第2期22卷 203-212页

作者： Qiming zha.Feng Li Ranran Liu School of Electrical and Information Engineering Jiangsu University of TechnologyChangzhou213001JiangsuChina School of Automobile and Traffic Engineering Jiangsu University of TechnologyChangzhou213001JiangsuChina

In this research, we present a methodology to identify the Hammerstein nonlinear system with noisy output measurements. The Hammerstein system presented is comprised of neural fuzzy model (NFM) as its static nonlinear block and auto-regressive with extra input (ARX) model as its dynamic linear block, and a two-step procedure is accomplished using signal combination. In the first step, in the case of input–output of Gaussian signals, the correlation function-based least squares (CF-LS) technique is utilized to identify the linear block, solving the problem that the intermediate variable connecting nonlinear and linear blocks cannot be measured. In the second step, to improve the identification accuracy of the nonlinear block parameters, an improved particle swarm optimization technique is developed under input–output of random signals. The validity and accuracy of the presented scheme are verified by a numerical simulation and a practical nonlinear process, and the results illustrate that the proposed methodology can identify well the Hammerstein nonlinear system with noisy output measurements.

关键词： Hammerstein nonlinear system Signal combination Auto-regressive with extra input Improved particle swarm optimization

Geology and mineralization of the Dongping supergiant alkalic-hosted Au-Te deposit(>100 t Au)in Northern Hebei Province,China:A review

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China Geology 2024年第3期7卷 533-550页

作者： Shi-min Zhen Da-zha. Wang Zhong-jian zha.Hai-jun Bai Jiang Wang Development and Research Center of China Geological Survey Ministry of Natural ResourcesBeijing 100037China Technical Guidance Center for mineral Resources Exploration Ministry of Natural ResourcesBeijing 100037China State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China Institute of Geological Surveying and Mapping Technology of Anhui Province Hefei 230022China Third Geological Brigade of Hebei Bureau of Geology and mineral Resources Zhangjiakou 075000China Ulanqab Real Estate Registration Center Ulanqab 012099China

The Dongping deposit is the largest alkalic-hosted gold deposit in China containing>100 t of *** paper presents a new understanding for Dongping ore system,based on the previous *** mineralization originally occurred at 400-380 Ma,simultaneous with emplacement of the Shuiquangou alkaline complex,and was overprinted by the hydrothermal activity in the *** compositions of ores indicate metals of the deposit are mainly provided by the Shuiquangou ***-forming fluids are characterized by increasing oxygen fugacity and decreasing sulfur fugacity,while tellurium fugacity increased in the Stage II-2 and decreased in Stage *** systematic changes are closely related to the processes of mineral precipitation and fluid *** precipitation from Stage Ⅰ to Stage Ⅱ was triggered by fluid boiling,which leads to the precipitation of Pb-Bi-Te,due to decrement of sulfur *** of gas phase containing high concentration of H_2Te leads to precipitation of Te-Au-Ag minerals and native *** on these hypotheses,this paper present a polyphase metallogenic model as *** the Devonian,fluids were released from alkaline magmas,which carried ore-forming materials form the surrounding rocks and precipitate the early *** the Jurassic-Cretaceous,fluorine-rich fluids exsolved from highly factionated Shangshuiquan granite,which extracted and concentrated Au from the Shuiquangou complex and the Sanggan Group metamorphic rocks,and finally formed the Dongping gold deposit.

关键词： mineralization and alteration Alkaline intrusion Au deposit Physicochemical conditions Metallogenic model Oxygen fugacity Sulfur fugacity Mechanisms of mineral precipitation Fluid boiling Fluorine-enriched fluid Dongping gold deposit North China Craton mineral exploration engineering

Human pluripotent stem cell-derived kidney organoids:Current progress and challenges

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World Journal of Stem Cells 2024年第2期16卷 114-125页

作者： Hong-Yan Long Zu-ping Qian Qin Lan Yong-Jie Xu Jing-Jing Da Fu-Xun Yu Yan zha Graduate School Zunyi Medical UniversityZunyi 563000Guizhou ProvinceChina Department of Laboratory Medicine Guizhou Provincial People’s HospitalGuiyang 550002Guizhou ProvinceChina Department of Nephrology Guizhou Provincial People’s HospitalGuiyang 550002Guizhou ProvinceChina Key Laboratory of Diagnosis and Treatment of Pulmonary Immune Diseases National Health CommissionGuizhou Provincial People’s HospitalGuiyang 550002Guizhou ProvinceChina

Human pluripotent stem cell(hPSC)-derived kidney organoids share similarities with the fetal ***,the current hPSC-derived kidney organoids have some limitations,including the inability to perform nephrogenesis and lack of a corticomedullary definition,uniform vascular system,and coordinated exit path-way for urinary ***,further studies are required to produce hPSC-derived kidney organoids that accurately mimic human kidneys to facilitate research on kidney development,regeneration,disease modeling,and drug *** this review,we discussed recent advances in the generation of hPSC-derived kidney organoids,how these organoids contribute to the understanding of human kidney development and research in disease ***,the limitations,future research focus,and applications of hPSC-derived kidney organoids were highlighted.

关键词： Kidney Organoids Human pluripotent stem cell Development Vascular system Disease modeling

Preparing cyclic polymers at high concentrations via self-folding cyclization technique by adjusting the contents of hydrophilic units in linear precursors

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Chinese Chemical Letters 2024年第2期35卷 283-288页

作者： Hao zha.Zuowei Wang Chao Liu Chunyan Hong Department of Polymer Science and Engineering University of Science and Technology of ChinaHefei 230026China Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China

Cyclic polymers are a class of polymers that feature endless topology,and the synthesis of cyclic polymers has attracted the attention of many ***,cyclic polymers were efficiently constructed by self-folding cyclization technique at high *** poly((oligo(ethylene glycol)acrylate)-co-(dodecyl acrylate))(P(OEGA-co-DDA))precursors with different ratios of hydrophilic and hydrophobic moieties were synthesized by reversible addition-fragmentation chain transfer(RAFT)polymerization using a bifunctional chain transfer agent with two anthryl end *** amphiphilic linear precursors underwent the self-folding process to generate polymeric nanoparticles in *** irradiating the aqueous solution of the nanoparticles with 365 nm UV light,cyclic polymers were synthesized successfully via coupling of anthryl *** effects of the ratios of hydrophilic and hydrophobic moieties in linear P(OEGA-co-DDA)copolymers and polymer concentration on the purity of the obtained cyclic polymers were explored in detail via ^(1)H nuclear magnetic resonance(^(1)H NMR),dynamic light scattering(DLS),UV‒visible(vis)analysis,three-detection size exclusion chromatography(TD-SEC)and transmission electron microscopy(TEM).It was found that by adjusting the content of the hydrophilic segments in linear precursors,single chain polymeric nanoparticles(SCPNs)can be generated at high polymer ***,cyclic polymers with high purity can be constructed *** method overcomes the limitation of traditional ring-closure method,which is typically conducted in highly dilute conditions,providing an efficient method for the scalable preparation of cyclic polymers.

关键词： Cyclic polymers Self-folding cyclization technique Single chain polymeric nanoparticles RAFT polymerization Direct visualization

Underwater four-quadrant dual-beam circumferential scanning laser fuze using nonlinear adaptive backscatter filter based on pauseable SAF-LMS algorithm

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Defence Technology（防务技术） 2024年第7期37卷 1-13页

作者： Guangbo Xu Bingting zha.Hailu Yuan Zhen Zheng He zha.g ministerial Key Laboratory of ZNDY Nanjing University of Science and TechnologyNanjing 210094China Science and Technology on Electromechanical Dynamic Control Laboratory Beijing 100081China Shanghai Radio Equipment Research Institute Shanghai 201109China

The phenomenon of a target echo peak overlapping with the backscattered echo peak significantly undermines the detection range and precision of underwater laser *** overcome this issue,we propose a four-quadrant dual-beam circumferential scanning laser fuze to distinguish various interference signals and provide more real-time data for the backscatter filtering *** enhances the algorithm loading capability of the *** order to address the problem of insufficient filtering capacity in existing linear backscatter filtering algorithms,we develop a nonlinear backscattering adaptive filter based on the spline adaptive filter least mean square(SAF-LMS)*** also designed an algorithm pause module to retain the original trend of the target echo peak,improving the time discrimination accuracy and anti-interference capability of the ***,experiments are conducted with varying signal-to-noise ratios of the original underwater target echo *** experimental results show that the average signal-to-noise ratio before and after filtering can be improved by more than31 d B,with an increase of up to 76%in extreme detection distance.

关键词： Laser fuze Underwater laser detection Backscatter adaptive filter Spline least mean square algorithm Nonlinear filtering algorithm