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Accuracy Analysis and Design of A3 Parallel Spindle Head

Chinese Journal of Mechanical Engineering 2016年第2期29卷 239-249页

作者： NI Yanbing ZHANG Biao sun yupeng ZHANG Yuan School of Mechanical Engineering Tianjin University Tianjin 300072 China China Faw Group Corporation R&D Center Changchun 130000 China

As functional components of machine tools, parallel mechanisms are widely used in high efficiency machining of aviation components, and accuracy is one of the critical technical indexes. Lots of researchers have focused on the accuracy problem of parallel mechanisms, but in terms of controlling the errors and improving the accuracy in the stage of design and manufacturing, further efforts are required. Aiming at the accuracy design of a 3-DOF parallel spindle head（A3 head）, its error model, sensitivity analysis and tolerance allocation are investigated. Based on the inverse kinematic analysis, the error model of A3 head is established by using the first-order perturbation theory and vector chain method. According to the mapping property of motion and constraint Jacobian matrix, the compensatable and uncompensatable error sources which affect the accuracy in the end-effector are separated. Furthermore, sensitivity analysis is performed on the uncompensatable error sources. The sensitivity probabilistic model is established and the global sensitivity index is proposed to analyze the influence of the uncompensatable error sources on the accuracy in the end-effector of the mechanism. The results show that orientation error sources have bigger effect on the accuracy in the end-effector. Based upon the sensitivity analysis results, the tolerance design is converted into the issue of nonlinearly constrained optimization with the manufacturing cost minimum being the optimization objective. By utilizing the genetic algorithm, the allocation of the tolerances on each component is finally determined. According to the tolerance allocation results, the tolerance ranges of ten kinds of geometric error sources are obtained. These research achievements can provide fundamental guidelines for component manufacturing and assembly of this kind of parallel mechanisms.

关键词： A3 head error model sensitivity analysis tolerance allocation

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A self-adaptive correction method for perspective distortions of image

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Frontiers of Computer Science 2019年第3期13卷 588-598页

作者： Lihua WU Qinghua SHANG yupeng sun Xu BAI School of Measurement and Communication Harbin University of Science and Technology Harbin 150080 China

Frequently, the shooting angles available to photograph an object are limited, and the resultant images contain perspective distortions. These distortions make more difficult to perform subsequent tasks like feature extraction and information identification. This paper suggested a perspective correction method that extracts automatically distortion features through edge detection. Results showed that this method is powerful in correcting images with perspective distortions. The corrected image has virtually little information missing, clear features and high recovery rate.

关键词： perspective correction perspective transformation Hough transform edge detection

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Effects of Aerobic and Anoxic Conditions on the Corrosion Behavior of NiCu Low Alloy Steel in the Simulated Groundwater Solutions

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Acta Metallurgica Sinica(English Letters) 2023年第5期36卷 745-757页

作者： Xin Wei yupeng sun Junhua Dong Nan Chen Qiying Ren Wei Ke Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei230026China Environmental Corrosion Centre of Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

The present work focused on investigating the corrosion behavior of NiCu low alloy steel in 0.05 M NaHCO_(3) solutions with different Cl−concentrations under the aerobic–anoxic *** results showed that NiCu steel tended to be pseudo-passivated in the solutions of 0.05 M NaHCO_(3) and 0.05 M NaHCO_(3)+0.01 M NaCl exposed to *** cathodic process transformed from oxygen reduction to the common reduction of oxygen andα-FeOOH,while the anodic process was the iron *** Cl^(−)increased to 0.1 M,the steel tended to be activity *** to the blocking effect of rust layer on the oxygen,the cathodic process transformed to the reduction ofα-*** the solutions were deoxidized,the cathodic process was controlled by only rust ***,both the cathodic process and anodic process of NiCu steel corrosion were significantly *** the whole aerobic–anoxic immersion,the corrosion rate of NiCu steel increased with Cl^(−)*** was not only related to the promotion of Cl^(−)on the anodic dissolution of steel,but also related to the cathodic reduction of moreα-FeOOH generated,which could accelerate the cathodic process.

关键词： Low alloy steel Aerobic-anoxic condition Corrosion behavior Corrosion products Electrochemical measurements

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Understanding the role of alloyed Ni and Cu on improving corrosion resistance of low alloy steel in the simulated Beishan groundwater

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Journal of Materials Science & Technology 2022年第35期130卷 124-135页

作者： yupeng sun Xin Wei Junhua Dong Nan Chen Hanyu Zhao Qiying Ren Wei Ke School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Environmental Corrosion Centre of Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

The corrosion behavior of NiCu low alloy steel and Q235 low carbon steel as the candidate materials for geological disposal containers of high-level radioactive waste in the simulated Beishan groundwater was comparatively studied by weight loss test,electrochemical measurements,scanning electron microscope(SEM),electron probe microanalysis(EPMA),X-ray diffraction(XRD),Raman spectrum and X-ray photoelectron spectroscopy(XPS).The electrochemical results showed that the corrosion potential of NiCu steel and Q235 steel gradually increased with the immersion ***,the cathodic process transited from hydrogen evolution reaction(HER) control to the rust reduction control,while the anodic process was always dominated by the active dissolution of *** comparison,both the cathodic resistance and the anodic dissolution resistance of NiCu steel corrosion were apparently higher than that of Q235 *** results of rust layer characterization indicated that Ni and Cu elements could be enriched in the inner rust layer of NiCu steel and the rust layer was more *** the main corrosion products,the content of α-FeOOH in the rust layer of NiCu steel was obviously increased more than that of Q235 ***_(6)(OH)_(12)SO_(4)stably existed in the corrosion products of NiCu steel because Ni(Ⅱ) or Cu(Ⅱ)could substitute Fe(Ⅱ) of Fe_(6)(OH)_(12)SO_(4)and increased its oxidation resistance,Moreover,Ni and Cu could also make Fe3O4ionic selective by *** the long-term immersion,the corrosion mass loss of NiCu steel was significantly lower than Q235 steel,which further confirmed the benefits of Ni and Cu alloying on improving the steel corrosion resistance.

关键词： Deep geological disposal Container material Groundwater Corrosion behavior Electrochemical measurement

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Metallic and ferromagnetic MoS2 nanobelts with vertically aligned edges

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Nano Research 2015年第9期8卷 2946-2953页

作者： Guanchen Xu Xinsheng Wang yupeng sun Xiao Chen Jingying Zheng Lifei sun Liying Jiao Jinghong Li Department of Chemistry Tsinghua University Beijing 100084 China Key Laboratory of Colloid and Interface Chemistry Shandong University Jinan 250100 China

Edge effects are predicted to significantly impact the properties of low dimensional materials with layered structures. The synthesis of low dimensional materials with copious edges is desired for exploring the effects of edges on the band structure and properties of these materials. Here we developed an approach for synthesizing MoS2 nanobelts terminated with vertically aligned edges by sulfurizing hydrothermally synthesized MoO3 nanobelts in the gas phase through a kinetically driven process; we then investigated the electrical and magnetic properties of these metastable materials. These edge-terminated MoS2 nanobelts were found to be metallic and ferromagnetic, and thus dramatically different from the semiconducting and nonmagnetic two-dimensional （2D） and three-dimensional （3D） 2H-MoS2 materials. The transitions in electrical and magnetic properties elucidate the fact that edges can tune the properties of low dimensional materials. The unique structure and properties of this one-dimensional （1D） MoS2 material will enable its applications in electronics, spintronics, and catalysis.

关键词： MoS2 two-dimensional (2D)atomic crystal,nanobelt,edge effect,metallic,ferromagnetic

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Influence of Deteriorated Bentonite Sediments on the Corrosion Behavior of NiCu Low Alloy Steel

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Acta Metallurgica Sinica(English Letters) 2022年第6期35卷 1011-1022页

作者： Xin Wei Junhua Dong yupeng sun Nan Chen Qiying Ren Madhusudan Dhakal Xiaofang Li Wei Ke Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Environmental Corrosion Centre of Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China

The corrosion evolution of steel disposal container largely depends on the evolution of surrounding bentonite environment in the long-term geological disposal of high-level radioactive wastes. This study focused on the influence of the deteriorated bentonite sediments on the corrosion behavior of NiCu low alloy steel in the top supernatant and bottom slurry formed by Gaomiaozi bentonite and 0.05 M NaHCO_(3) + 0.1 M NaCl + 0.1 M Na_(2)SO_(4) solution. In the top supernatant, the cathodic process of the steel corrosion was transformed from the reduction in oxygen to the reduction in ferric corrosion products with time as same as that in the blank solution. While in the bottom bentonite slurry, the cathodic process always maintained as the hydrogen evolution reaction due to the coverage of more bentonite sediments. Meanwhile, the corrosion rate of NiCu steel was obviously decreased. In addition, the localized corrosion tendency of the steel could also be reduced by the large amount of deteriorated bentonite sediments.

关键词： Low alloy steel Bentonite Corrosion behavior Corrosion products Electrochemical impedance spectroscopy(EIS)

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Improved corrosion resistance and biofilm inhibition ability of copper-bearing 304 stainless steel against oral microaerobic Streptococcus mutans

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Journal of Materials Science & Technology 2021年第7期66卷 112-120页

作者： Hanyu Zhao yupeng sun Lu Yin Zhao Yuan Yiliang Lan Dake Xu Chunguang Yang Ke Yang School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China Institute of Metal Research Chinese Academy of SciencesShenyang110016China Shenyang National Laboratory for Materials Science Northeastern UniversityShenyang110819China

304 stainless steel(SS) used as orthodontic wire during orthodontics faces the risk of microbiologically influenced corrosion(MIC) due to diverse flora environment. Hereinto, Streptococcus mutans(S. mutans)is the most important cariogenic bacteria. In this work, MIC behavior of a new 304-Cu SS in presence of S. mutans was studied by the observations using scanning electron microscopy(SEM) and confocal laser scanning microscopy(CLSM) including live/dead staining, extracellular polymeric substance(EPS)staining and pitting corrosion, electrochemical test, and X-ray photoelectron spectroscopy(XPS). Above results showed that 304-Cu SS possessed excellent biofilm inhibition ability and presented lower corrosion current density(icorr), larger polarization resistance(Rp) and charge transfer resistance(Rct) in the presence of S. mutans, indicating that 304-Cu SS had a better MIC resistance against S. mutans. It was further affirmed by XPS results that the presence of Cu-oxide in passive film of 304-Cu SS inhibited the formation of biofilm.

关键词： 304-Cu stainless steel Microbiologically influenced corrosion Streptococcus mutans Biofilm

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Spraying Arginine at 5 Days before Harvest Delays Postharvest Broccoli Senescence via Nutrient Accumulation

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食品科学 2025年第1期46卷 131-141页

作者： sun yupeng CHEN Ying SHANG Qingwen GUO Yanyin ZHANG Yuxiao WANG Yunqiao XUE Qingyue College of Agricultural Engineering and Food Science Shandong University of TechnologyZibo 255049China Zichuan District Agricultural and Rural Affairs Service Center Zibo 255049China

To determine the effects of preharvest arginine spraying on the nutritional level of broccoli and the mechanism of action of arginine in improving the storage quality of broccoli,arginine spraying(5 mmol/L)was conducted at 0,1,3,and 5 days before *** appearance,respiration rate,mass-loss rate,electrolyte leakage,glucosinolate,ascorbic acid,total phenol,total flavonoid,total sugar and sucrose contents,and sucrose phosphate synthase(SPS),invertase(INV),sucrose synthase synthesis(SSS)and cleavage(SSC)activities of broccoli samples were observed after 0,2,4,6,8,and 10 days of *** results showed that spraying arginine at 5 days preharvest(5-ARG)helped to inhibit broccoli respiration during storage,delay electrolyte leakage,and maintain broccoli ***,during the growth stage,total sugar accumulation was higher in the 5-ARG *** addition,during the storage period,sucrose synthesis was accelerated,while sucrose cleavage was inhibited,resulting in more sucrose retention in postharvest *** conclusion,5-ARG resulted in the accumulation of more nutrients during the growth process and effectively delayed the quality decline during storage,thereby prolonging the shelf life of ***,this study provides a theoretical basis for improving postharvest storage characteristics of broccoli through preharvest treatments.

关键词： arginine broccoli preharvest spraying nutrient accumulation storage quality postharvest senescence

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Simultaneous quantification of ginsenoside Rg1 and its metabolites by HPLC–MS/MS:Rg1 excretion in rat bile, urine and feces

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Acta Pharmaceutica Sinica B 2016年第6期6卷 593-599页

作者： Chiyu He Ru Feng yupeng sun Shifeng Chu Ji Chen Chao Ma Jie Fu Zhenxiong Zhao Min Huang Jiawen Shou Xiaoyang Li Yuzhu Wang Jinfeng Hu Yan Wang Juntian Zhang State Key Laboratory of Bioactive Substances and Functions of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences Beijing Analytical Application Center Shimadzu (China) Co. Ltd.

Ginsenoside Rg1(Rg1), the major effective component of ginseng, has been shown to have multiple bioactivities, but low oral bioavailability. The aim of this study was to develop a simple, sensitive and rapid high performance liquid chromatography–tandem mass spectrometry(LC–MS/MS) method, which could be used to validate and quantify the concentrations of Rg1 and its metabolites in Sprague-Dawley rat bile,urine, and feces after oral administration(25 mg/kg). Calibration curves offered satisfactory linearity(r40.995)within the determined ranges. Both intra-day and inter-day variances were less than 15%, and the accuracy was within 80–120%. The excretion recoveries of Rg1, ginsenoside Rh1(Rh1), and protopanaxatriol(Ppt) in bile,urine, and feces combined were all greater than 70%. The fecal excretion recoveries of Rg1, Rh1, and Ppt were40.11%, 22.19%, and 22.88%, respectively, whereas 6.88% of Rg1 and 0.09% of Rh1 were excreted in *** excretion accounted for only 0.04% of Rg1. In conclusion, the observed excretion profiles for Rg1 and its metabolites after oral administration are helpful for understanding the poor oral bioavailability of Rg1 and will aid further investigations of Rg1 as a pharmacologically active component.

关键词： Ginsenoside Rg1 Ginsenoside Rh1 Protopanaxatriol Excretion LC–MS/MS

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Diagnosis and Treatment and Infection Protection Strategy of Osteoporotic Vertebral Compression Fractures Minimally Invasive Percutaneous Kyphoplasty Surgery during the Prevention and Control of COVID-19

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Surgical Science 2022年第12期13卷 541-550页

作者： Xinming Yang Chaowei Yang Lixing Chen Yao Yao Ye Tian yupeng sun The First Affiliated Hospital of Hebei North University Zhangjiakou China Graduate School of Hebei North University Zhangjiakou China

Background: As the global novel coronavirus pneumonia (NCP) remains severe, elderly people are at high risk for NCP and osteoporotic vertebral compression fractures, with high complications and mortality. How to treat patients and protect medical staff from infection, and at the same time strictly prevent the occurrence of clustered transmission events in the hospital, the establishment of perfect pre-hospital emergency measures and infection prevention and control strategy is the first element to ensure success. Objective: To establish the diagnosis and treatment and infection protection strategy for Osteoporotic vertebral compression fractures (OVCF) patients undergoing minimally invasive percutaneous kyphoplasty (PKP) surgery during the prevention and control of COVID-19, so as to ensure the stable, orderly and safe medical treatment. Methods: A total of 583 OVCF patients were admitted to the First Affiliated Hospital of Hebei North University during the epidemic prevention and control period from January 2020 to July 2022. After urgent and outpatient strict standardized screening, 382 patients met the inclusion criteria, including 112 males and 270 females, aged (70.50 ± 5.49) years. The preoperative visual analogue scale (VAS) score was 6.92 ± 1.86. Preoperative Oswestry disability index (ODI) was 74.67 ± 4.84. The satisfaction rate was (45.89 ± 3.67) %. According to the clinical diagnostic criteria and classification, 367 patients were diagnosed as ordinary OVCF, including 156 cases of mild compression and 226 cases of moderate compression. The clinical classification of 15 patients with OVCF diagnosed as COVID-19 was type I, including 10 cases of mild COVID-19 and 5 cases of common COVID-19. All patients were treated with PKP. Results: All patients were followed up at 1 day, 1 month and 3 months after operation, VAS (2.01 ± 0.56, 0.45 ± 0.11, 0 ± 0), ODI (45.41 ± 4.15, 10.22 ± 2.73, 4.03 ± 1.57) and satisfaction (90.12%, 95.57%, 99.23%) were significantly imp

关键词： COVID-19 Osteoporotic Vertebral Compression Fractures Diagnosis and Treatment Percutaneous Kyphoplasty Operating Room Management Infection Protection

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