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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 zhang 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

Effect of nucleating agents on the electrical properties of cross-linked polyethylene under tensile stress

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High Voltage 2024年第2期9卷 429-439页

作者： Yunqi Xing Jiahao Liu Jingang Su Junwei zha guochang Li Ze guo Xiaozhen zhao Mengjia feng State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of TechnologyTianjinChina Electric Power Research Institute of State grid Hebei Electric Power Supply Co. Ltd.ShijiazhuangChina Beijing Advanced Innovation Center for Materials genome Engineering School of Chemistry and Biological EngineeringUniversity of Science&Technology BeijingBeijingChina Institute of Advanced Electrical Materials Qingdao University of Science and TechnologyQingdaoChina

During the operation of high-voltage cables,external stress and residual stress can affect the aggregated structure of insulating materials and lead to significant deterioration in their electrical *** investigate the evolution characteristics of the electrical properties of cross-linked polyethylene(XLPE)under mechanical stress,this paper ex-plains the relationship between the aggregated structure of XLPE and its electrical properties and proposes a method for improving insulation performance under me-chanical *** results show that metallocene polyethylene used as a nucleating agent can promote crystallisation through heterogeneous nucleation and increase Young's modulus by non-uniform nucleation,increasing crystallinity and reducing interplanar spacing,resulting in more complete crystal forms and reduced damage to the aggregated structure during the tensile *** nucleating agent modification,the XLPE crystallisation becomes more uniform,and interfacial adhesion forces *** weakened interface damage process between the amorphous and crystalline regions under tensile stress effectively inhibits the process of molecular chain polarisation turning and reduces trap *** modified XLPE crystal structure shows a tendency towards densification and enhanced molecular chain interactions,which can reduce the damage to the aggregated structure under tensile stress,while the reduced free volume inside the material and the shortened average free path of carriers can weaken the damage of high-energy electrons to molecular chains,thereby inhibiting the process of electrical tree *** results show that nucleating agents have great potential for maintaining the stable operation of XLPE cables under mechanical stress.

关键词： stress electrical damage

A breathable, designable and flexible leather–heater used in wearable thermotherapy

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Science China(Technological Sciences) 2024年第7期67卷 2125-2132页

作者： ZHU JingYu LIU Yado.g XIE RuiJie zhaO YuHan WANg feng LIU YunQing zha BaoLi WU JianSheng HUO fengWei Key Laboratory of Flexible Electronics(KLOFE) School of Flexible Electronics(Future Technologies)Institute of Advanced Materials(IAM)Nanjing Tech UniversityNanjing 211816China The Institute of Flexible Electronics(IFE Future Technologies)Xiamen UniversityXiamen 361005China Tan Kah Kee Innovation Laboratory Xiamen 361102China

Flexible heaters with personal thermal management capabilities have great potential in thermal therapy applications due to their excellent flexibility, low power consumption, and portability. However, manufacturing wearable heating devices that are breathable, wear resistant and conformal for long-term use is still challenging. To address these issues, we designed a leather heater using breathable, biocompatible, and tailorable leather as the substrate through a simple in-situ polymerization polypyrrole strategy. This heater exhibits excellent heating and mechanical properties(reaching 64℃ at a voltage of 5 V with efficient Joule heat generation of 2286 W/m^(2)and uniform temperature distribution, and functioning properly after 1000 cycles of bendability tests). In addition, this heater displays better wear resistance and water vapor permeability rate(38.04 g/(m^(2)h)). The cuttable and sewable of leather gives the strategy ability to be flexibly designed to mold the heater to the specific requirements of different body parts, providing a new approach to wearable thermal therapy.

关键词： flexible electronics leather thermotherapy

Predictive visual field outcomes after optic chiasm decompressive surgery by retinal vessels parameters using optical coherence tomography angiography

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International Journal of Ophthalmology(English edition) 2024年第2期17卷 365-373页

作者： Wen-Juan Yu Jin Xiao guang-Xin Wang Chang Jiang Wei zha Rong-feng Liao Department of Ophthalmology the First Affiliated Hospital of Anhui Medical UniversityHefei 230022Anhui ProvinceChina Department of Neurosurgery the First Affiliated Hospital of Anhui Medical UniversityHefei 230022Anhui ProvinceChina Department of Ophthalmology the First People’s Hospital of HefeiHefei 230061Anhui ProvinceChina

AIM:To evaluate the predictive value of superficial retinal capillary plexus(SRCP)and radial peripapillary capillary(RPC)for visual field recovery after optic cross decompression and compare them with peripapillary nerve fiber layer(pRNFL)and ganglion cell complex(gCC).METHODS:This prospective longitudinal observational study included patients with chiasmal compression due to sellar region mass scheduled for decompressive *** estimating equations were used to compare retinal vessel density and retinal layer thickness preand post-operatively and with healthy *** regression models were used to assess the relationship between preoperative gCC,pRNFL,SRCP,and RPC parameters and visual field recovery after ***:The study included 43 eyes of 24 patients and 48 eyes of 24 healthy *** RPC and SRCP vessel density and pRNFL and gCC thickness were lower than healthy controls and higher than postoperative *** best predictive gCC and pRNFL models were based on the superior gCC[area under the curve(AUC)=0.866]and the tempo-inferior pRNFL(AUC=0.824),and the best predictive SRCP and RPC models were based on the nasal SRCP(AUC=0.718)and tempo-inferior RPC(AUC=0.825).There was no statistical difference in the predictive value of the superior gCC,tempo-inferior pRNFL,and tempo-inferior RPC(all P>0.05).CONCLUSION:Compression of the optic chiasm by tumors in the saddle area can reduce retinal thickness and blood *** reduction persists despite the recovery of the visual field after decompression ***,pRNFL,and RPC can be used as sensitive predictors of visual field recovery after decompression surgery.

关键词： sellar region mass retinal vessels optic chiasm optical coherence tomography angiography visual field decompressive surgery

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 do.g 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

Clonal hematopoiesis:a shared risk factor for cardiovascular diseases and tumors

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Oncology and Translational Medicine 2024年第1期10卷 35-41页

作者： Ling-feng zha Xiang Cheng Department of Cardiology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina Hubei Key Laboratory of Biological Targeted Therapy Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina Hubei Provincial Engineering Research Center of Immunological Diagnosis and Therapy for Cardiovascular Diseases Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina

Clonal hematopoiesis(CH)is a clonally expanded population of hematopoietic stem cells carrying somatic mutations that differentiate through multilineage hematopoiesis to form terminally differentiated mature hematopoietic cells carrying markers of the clonal *** integral to critical cellular processes such as epigenetic regulation,DNA damage response,and inflammation frequently carry these *** hematopoiesis becomes increasingly prevalent with age and is associated with an increased risk of hematological tumors and some nonhematological *** insights have revealed that the mutations driving CH are not only implicated in hematologic neoplasms but also possess the potential to influence cardiovascular ***,we reviewed up-to-date findings about the roles of CH in cardiovascular diseases and tumors and explored the clinical significance of CH,as well as look forward to future related studies,so as to provide valuable references for future research and clinical practice.

关键词： Cardiovascular diseases Clonal hematopoiesis Tumors

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 zhang 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

Novel PIKfyve/Tubulin Dual-target Inhibitor as a Promising Therapeutic Strategy for B-cell Acute Lymphoblastic Leukemia

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Current Medical Science 2024年第2期44卷 298-308页

作者： Zhen LU Qian LAI Zhi-feng LI Meng-ya ZHONg Yue-long JIANg Li-ying feng Jie zha Jing-wei YAO Yin LI Xian-ming DENg Bing XU Department of Hematology The First Affiliated Hospital of Xiamen University and Institute of HematologySchool of MedicineXiamen UniversityXiamen361005China Key Laboratory of Xiamen for Diagnosis and Treatment of Hematological Malignancy Xiamen361005China Department of Oncology The First Affiliated Hospital of Jinan UniversityJinan UniversityGuangzhou510630China State Key Laboratory of Cellular Stress Biology Innovation Center for Cell Signaling NetworkSchool of Life SciencesXiamen UniversityXiamen361003China

Objective:In B-cell acute lymphoblastic leukemia(B-ALL),current intensive chemotherapies for adult patients fail to achieve durable responses in more than 50%of cases,underscoring the urgent need for new therapeutic regimens for this patient *** present study aimed to determine whether HZX-02-059,a novel dual-target inhibitor targeting both phosphatidylinositol-3-phosphate 5-kinase(PIKfyve)and tubulin,is lethal to B-ALL cells and is a potential therapeutic for B-ALL ***:Cell proliferation,vacuolization,apoptosis,cell cycle,and in-vivo tumor growth were *** addition,genome-wide RNA-sequencing studies were conducted to elucidate the mechanisms of action underlying the anti-leukemia activity of HZX-02-059 in ***:HZX-02-059 was found to inhibit cell proliferation,induce vacuolization,promote apoptosis,block the cell cycle,and reduce in-vivo tumor *** of the p53 pathway and suppression of the phosphoinositide 3-kinase(PI3K)/AKT pathway and the downstream transcription factors c-Myc and NF-κB were responsible for these ***:Overall,these findings suggest that HZX-02-059 is a promising agent for the treatment of B-ALL patients resistant to conventional therapies.

关键词： B-cell acute lymphoblastic leukemia dual-target inhibitor NF-kB c-Myc PI3K/AKT p53