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geometric Error Identification of gantry-Type CNC Machine Tool Based on Multi-station synchronization Laser Tracers

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

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Risk factors for postpartum posttraumatic stress disorder after emergency admission

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World Journal of Emergency Medicine 2024年第2期15卷 121-125页

作者： Fengxia Du Jun zha Yan Li Lichao Fang shuyu Xia Youjia Yu Department of Obstetrics Suzhou Xiangcheng People’s HospitalSuzhou 215131China Department of Anesthesiology the Second Affiliated Hospital of Wannan Medical CollegeWuhu 241000China Department of Anesthesiology Suzhou Xiangcheng People’s HospitalSuzhou 215131China Department of Emergency and Intensive Care Unit Suzhou Xiangcheng People’s HospitalSuzhou 215131China

BACKgROUND:Postpartum posttraumatic stress disorder(PTsD)can occur in women who give birth after emergency *** identification of risk factors for this condition is crucial for developing effective preventive *** retrospective study aimed to explore the incidence and risk factors for postpartum PTsD in women who give birth after emergency ***:Medical records of women who gave birth after emergency admission were collected between March 2021 and April *** patients’general conditions and perinatal clinical indicators were *** puerperae were divided into PTsD group and control group based on symptom occurrence at six weeks *** logistic regression analysis was performed to identify risk ***:A total of 276 puerperae were included,with a PTsD incidence of 20.3% at six weeks *** logistic regression analysis identified emergency cesarean section(odds ratio[OR]=2.102;95%confidence interval[CI]:1.114-3.966,P=0.022),admission to the emergency department after midnight(12:00 AM)(OR=2.245;95%CI:1.170-4.305,Ps independent risk factors for postpartum *** pump use(OR=0.500;95%CI:0.259–0.966,P=0.015)was found to be a protective factor against postpartum ***:Emergency cesarean section,admission to the emergency department after midnight,and cervical dilation were identified as independent risk factors for postpartum PTsD,while analgesic pump use was a protective *** findings provide insights for developing more effective preventive measures for women who give birth after emergency admission.

关键词： Risk factors Posttraumatic stress disorder Emergency Delivery

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Intramolecular Hydrogen Bond Improved Durability and Kinetics for Zinc‑Organic Batteries

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Nano-Micro Letters 2024年第3期16卷 138-148页

作者： Tianjiang sun Jun Pan Weijia zha.g Xiaodi Jiang Min Cheng Zhengtai zha Hong Jin Fan zhanliang Tao Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Renewable Energy Conversion and Storage CenterCollege of ChemistryNankai UniversityHaihe Laboratory of Sustainable Chemical TransformationsTianjin 300071People’s Republic of China school of Physical and Mathematical sciences Nanyang Technological UniversitySingapore 637371Singapore shanghai Key Laboratory of special Artificial Microstructure Materials and Technology School of Physics Science and EngineeringTongji UniversityShanghai 200092People’s Republic of China

Organic compounds have the advantages of green sustainability and high designability,but their high solubility leads to poor durability of zinc-organic ***,a high-performance quinone-based polymer(H-PNADBQ)material is designed by introducing an intramolecular hydrogen bonding(HB)*** intramolecular HB(C=O⋯N-H)is formed in the reaction of 1,4-benzoquinone and 1,5-naphthalene diamine,which efficiently reduces the H-PNADBQ solubility and enhances its charge transfer in *** situ ultraviolet-visible analysis further reveals the insolubility of H-PNADBQ during the electrochemical cycles,enabling high durability at different current ***,the H-PNADBQ electrode with high loading(10 mg cm^(-2))performs a long cycling life at 125 mA g^(-1)(>290 cycles).The H-PNADBQ also shows high rate capability(137.1 mAh g^(−1)at 25 A g^(−1))due to significantly improved kinetics inducted by intramolecular *** work provides an efficient approach toward insoluble organic electrode materials.

关键词： Zn-organic batteries H-PNADBQ polymer Intramolecular hydrogen bond Reduced solubility Improvedπ-conjugated level

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Defect Engineering and Carbon supporting to Achieve Ni‑Doped CoP_(3) with High Catalytic Activities for Overall Water splitting

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Nano-Micro Letters 2024年第11期16卷 569-584页

作者： Daowei zha Ruoxing Wang shijun Tian Zhong‑Jie Jiang Zejun Xu Chu Qin Xiaoning Tian Zhongqing Jiang Department of Physics Zhejiang Sci-Tech UniversityHangzhou 310018People’s Republic of China Department of Materials and Chemical Engineering Ningbo University of TechnologyNingbo 315211People’s Republic of China guangzhou Key Laboratory for surface Chemistry of Energy Materials Guangdong Engineering and Technology Research Center for Surface Chemistry of Energy MaterialsCollege of Environment and EnergySouth China University of TechnologyGuangzhou 510006People’s Republic of China

This work reports the use of defect engineering and carbon supporting to achieve metal-doped phosphides with high activities and stabilities for the hydrogen evolution reaction(HER)and the oxygen evolution reaction(OER)in alkaline ***,the nitrogen-doped carbon nanofiber-supported Ni-doped CoP_(3) with rich P defects(Pv·)on the carbon cloth(p-NiCoP/NCFs@CC)is synthesized through a plasma-assisted phosphorization *** p-NiCoP/NCFs@CC is an efficient and stable catalyst for the HER and the *** only needs overpotentials of 107 and 306 mV to drive 100 mA cm^(-2) for the HER and the OER,*** catalytic activities are higher than those of other catalysts reported *** high activities of the p-NiCoP/NCFs@CC mainly arise from its peculiar structural *** density functional theory calculation indicates that the Pv·richness,the Ni doping,and the carbon supporting can optimize the adsorption of the H atoms at the catalyst surface and promote the strong electronic couplings between the carbon nanofiber-supported p-NiCoP with the surface oxide layer formed during the OER *** gives the p-NiCoP/NCFs@CC with the high activities for the HER and the *** used in alkaline water electrolyzers,the p-NiCoP/NCFs@CC shows the superior activity and excellent stability for overall water splitting.

关键词： Plasma Electrocatalysis Hydrogen evolution reaction Oxygen evolution reaction Water splitting

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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

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Mechanisms underlying the role of endoplasmic reticulum stress in the placental injury and fetal growth restriction in an ovine gestation model

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Journal of Animal science and Biotechnology 2024年第1期15卷 201-217页

作者： Hao zha.g Xia zha Yi Zheng Xiaoyun Liu Mabrouk Elsabagh Hongrong Wang Honghua Jiang Mengzhi Wang Laboratory of Metabolic Manipulation of Herbivorous Animal Nutrition College of Animal Science and TechnologyYangzhou UniversityYangzhou 225009P.R.China Joint International Research Laboratory of Agriculture and Agri‑Product safety Ministry of Education of ChinaYangzhou UniversityYangzhou 225009P.R.China Department of Animal Production and Technology Faculty of Agricultural Sciences and TechnologiesNiğde Omer Halisdemir UniversityNigde 51240Turkey Department of Nutrition and Clinical Nutrition Faculty of Veterinary MedicineKafrelsheikh UniversityKafrelSheikhEgypt Department of Pediatrics Northern Jiangsu People’s HospitalClinical Medical CollegeYangzhou UniversityYangzhou 225001China state Key Laboratory of sheep genetic Improvement and Healthy Production Xinjiang Academy of Agricultural Reclamation ScienceShihezi 832000China

Background Exposure to bisphenol A(BPA),an environmental pollutant known for its endocrine-disrupting properties,during gestation has been reported to increase the risk of fetal growth restriction(FgR)in an ovine model of *** hypothesized that the FgR results from the BPA-induced insufficiency and barrier dysfunction of the placenta,oxidative stress,inflammatory responses,autophagy and endoplasmic reticulum stress(ERs).However,precise mechanisms underlying the BPA-induced placental dysfunction,and subsequently,FgR,as well as the potential involvement of placental ERs in these complications,remain to be *** In vivo experiment,16 twin-pregnant(from d 40 to 130 of gestation)Hu ewes were randomly distributed into two groups(8 ewes each).One group served as a control and received corn oil once a day,whereas the other group received BPA(5 mg/kg/d as a subcutaneous injection).In vitro study,ovine trophoblast cells(OTCs)were exposed to 4 treatments,6 replicates *** OTCs were treated with 400μmol/L BPA,400μmol/L BPA+0.5μg/m L tunicamycin(Tm;ERs activator),400μmol/L BPA+1μmol/L 4-phenyl butyric acid(4-PBA;ERs antagonist)and DMEM/F12 complete medium(control),for 24 *** In vivo experiments,pregnant Hu ewes receiving the BPA from 40 to 130 days of pregnancy experienced a decrease in placental efficiency,progesterone(P4)level and fetal weight,and an increase in placental estrogen(E2)level,together with barrier dysfunctions,Os,inflammatory responses,autophagy and ERs in type A *** vitro experiment,the OTCs exposed to BPA for 24 h showed an increase in the E2 level and related protein and gene expressions of autophagy,ERs,pro-apoptosis and inflammatory response,and a decrease in the P4 level and the related protein and gene expressions of antioxidant,anti-apoptosis and barrier ***,treating the OTCs with Tm aggravated BPA-induced dysfunction of barrier and endocrine(the increased E2 level and decreased P4 level),Os,inflamm

关键词： Autophagy Bisphenol A Endoplasmic reticulum stress Fetal growth restriction Inflammatory responses sheep

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The coupling control of biological precursors and environmental factors onβ-carotane enrichment in alkaline lacustrine source rocks:A case study from the Fengcheng formation in the western Junggar Basin,NW China

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Petroleum science 2024年第2期21卷 836-854页

作者： Mao-guo Hou Ming zha Hua Liu Hai-Lei Liu Jiang-Xiu Qu Ablimit Imin Xiu-Jian Ding Zhong-Fa Jiang school of geosciences China University of PetroleumQingdaoShandong266580China Research Institute of Exploration and Development Xinjiang Petroleum Administration BureauKaramayXinjiang834000China

The organic-rich mudstones and dolostones of the Permian Fengcheng Formation(Fm.)are typically alkaline lacustrine source rocks,which are typified by impressively abundantβ-*** β-carotane has been well acknowledged as an effective indicator of biological sources or depositional ***,the specific biological sources of β-carotane and the coupling control of biological sources and environmental factors on the enrichment of β-carotane in the Fengcheng *** *** on a comprehensive investigation of the bulk,molecular geochemistry,and organic petrology of sedimentary rocks and the biochemistry of phytoplankton in modern alkaline lakes,we proposed a new understanding of the biological precursors of β-carotane and elucidated the enrichment mechanism of β-carotane in the Fengcheng *** results show that the biological precursors crucially control the enrichment of β-carotane in the Fengcheng *** haloalkaliphilic cyanobacteria are the primary biological sources of β-carotane,which is suggested by a good positive correlation between the 2-methylhopane index,7-+8-methyl heptadecanes/C_(max),C_(29%),and β-carotane/C_(max)in sedimentary rocks and the predominance of cyanobacteria with abundantβ-carotene in modern alkaline *** enrichment of β-carotane requires the reducing condition,and the paleoredox state that affects the enrichment of β-carotane appears to have a *** paleoclimate conditions do not considerably impact the enrichment of β-carotane,but they have some influence on the water's paleosalinity by affecting evaporation and *** it does not directly affect the enrichment of β-carotane in the Fengcheng Fm.,paleosalinity does have an impact on the cyanobacterial precursor supply and the preservation conditions.

关键词： β-carotane enrichment Cyanobacterial input Environmental impact Alkaline lacustrine source rocks The Fengcheng formation

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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

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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

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Oxygen‑Coordinated single Mn sites for Efficient Electrocatalytic Nitrate Reduction to Ammonia

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Nano-Micro Letters 2024年第1期16卷 147-159页

作者： shengbo zha.g Yuankang zha Yixing Ye Ke Li Yue Lin Lirong Zheng guozhong Wang Yunxia zha.g Huajie Yin Tongfei shi Haimin zha.g Laboratory of Materials Physics Centre for Environmental and Energy NanomaterialsAnhui Key Laboratory of Nanomaterials and NanotechnologyCAS Center for Excellence in NanoscienceInstitute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031People’s Republic of China University of science and Technology of China Hefei 230026People’s Republic of China Key Laboratory of Agricultural sensors Ministry of AgricultureSchool of Information and ComputerAnhui Agricultural UniversityHefei 230026People’s Republic of China Hefei National Research Center for Physical sciences at the Microscale University of Science and Technology of ChinaHefei 230026People’s Republic of China Beijing synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of Sciences19B Yuquan RoadBeijing 100049People’s Republic of China

Electrocatalytic nitrate reduction reaction has attracted increasing attention due to its goal of low carbon emission and environmental ***,we report an efficient NitRR catalyst composed of single Mn sites with atomically dispersed oxygen(O)coordination on bacterial cellulose-converted graphitic carbon(Mn-O-C).Evidence of the atomically dispersed Mn-(O-C_(2))_(4)moieties embedding in the exposed basal plane of carbon surface is confirmed by X-ray absorption *** a result,the as-synthesized Mn-O-C catalyst exhibits superior NitRR activity with an NH_(3)yield rate(RNH_(3))of 1476.9±62.6μg h^(−1)cm^(−2)at−0.7 V(*** hydrogen electrode,RHE)and a faradaic efficiency(FE)of 89.0±3.8%at−0.5 V(***)under ambient ***,when evaluated with a practical flow cell,Mn-O-C shows a high RNH_(3)of 3706.7±552.0μg h^(−1)cm^(−2)at a current density of 100 mA cm−2,2.5 times of that in the H *** in situ FT-IR and Raman spectroscopic studies combined with theoretical calculations indicate that the Mn-(O-C_(2))_(4)sites not only effectively inhibit the competitive hydrogen evolution reaction,but also greatly promote the adsorption and activation of nitrate(NO_(3)^(−)),thus boosting both the FE and selectivity of NH_(3)over Mn-(O-C_(2))_(4)sites.

关键词： Atomically dispersed Oxygen coordination Nitrate reduction reaction In situ spectroscopic studies Hydrogen evolution reaction

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