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A multi-objective optimization based on machine learning for dimension precision of wax pattern in turbine blade manufacturing

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Advances in Manufacturing 2024年第3期12卷 428-446页

作者： Jing Dai Song-zhe Xu Chao-Yue Chen Tao Hu San-San Shuai Wei-Dong Xuan Jiang Wang Zhong-Ming ren State Key Laboratory of Advanced Special Steels School of Materials Science and EngineeringShanghai UniversityShanghai200444People’s Republic of China

Wax pattern fabrication in the investment casting of hollow turbine blades directly determines the dimension accuracy of subsequent casting,and therefore significantly affects the quality of final *** this work,we develop a machine learning-based multi-objective optimization framework for improving dimension accuracy of wax pattern by optimizing its process *** consider two optimization objectives on the dimension of wax pattern,i.e.,the surface warpage and core *** active learning of Bayesian optimization is employed in data sampling to determine process parameters,and a validated numerical model of injection molding is used to compute objective results of dimension under varied process *** collected dataset is then leveraged to train different machine learning models,and it turns out that the Gaussian process regression model performs best in prediction accuracy,which is then used as the surrogate model in the optimization framework.A genetic algorithm is employed to produce a non-dominated Pareto front using the surrogate model in searching,followed by an entropy weight method to select the most optimal solution from the Pareto *** optimized set of process parameters is then compared to empirical parameters obtained from previous trial-and-error experiments,and it turns out that the maximum and average warpage results of the optimized solution decrease 26.0%and 20.2%,and the maximum and average errors of wall thickness compared to standard part decrease from 0.22 mm and 0.0517 mm using empirical parameters to 0.10 mm and 0.0356 mm using optimized parameters,*** framework is demonstrated capable of addressing the challenge of dimension control arising in the wax pattern production,and it can be reliably deployed in varied types of turbine blades to significantly reduce the manufacturing cost of turbine blades.

关键词： Hollow turbine blade Wax pattern fabrication Dimension control Multi-objective optimization Machine learning Numerical simulation

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Formation and evolution of Emeishan basalt saprolite in vadose zones of Touzhai landslide source rockmass

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Journal of Mountain Science 2017年第6期14卷 1174-1184页

作者： YANG Ji-qing XU Ze-min ZHANG Rui CHEN Ji-pu ren zhe LUO Rong-zhang ZHANG Xiu-shuo Faculty of Civil Engineering and Mechanics Kunming University of Science and Technology College of Architectural Engineering Yunnan Agricultural University

In order to explain the formation process of slope hazards, and to identify the key factors leading to instability of a slope, Emeishan basalt saprolite in vadose zones of the Touzhai landslide in Zhaotong, Yunnan, was studied. The formation and evolution of Emeishan basalt saprolite was examined using, amongst other techniques, field investigations,thin section analysis, scanning electron microscopy(SEM) observations, chemical analysis, physical and water-physical property tests of rock masses. Field observations revealed that the majority of the weathered rock blocks were presented as a concentric layer structure in which an internal corestone was enveloped with several layers of external saprolized crust. Chemical and mineralogical analysis identified that iron was the most sensitive element and that the weathering progress usually started with the oxidation of Fe2+ to Fe3+ in rock blocks. Alkaline elements such as Si, Ca, Mg, Na and K were also dissolved and Fe and Al were concentrated in saprolized crusts. Results indicated that loss on ignition(LOI) also increased significantly. SEM results showed that the weathering intensity of thebasalt blocks decreased gradually from the outside to the inside, and the mineral morphology significantly differed on both sides of the weathering front. The saprolized crusts presented cellular microstructure features due to the generation of micropore and clay minerals. Thin section analysis showed that plagioclase was relatively more stable than pyroxene and chlorite during weathering. With a centripetal propagation of the weathering front, saprolized crusts became thicker and corestones became smaller; fresh Emeishan basalt blocks gradually turned into saprolized blocks. Due to the loose structure and low strength of saprolite, the quality of the Emeishan basalt mass significantly deteriorated, this being a potentially important factor which caused the Touzhai landslide to occur.

关键词： Vadose zone Emeishan basalt Scanning electron microscopy Saprolite Corestone Touzhai landslide

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Efficient and selective removal of Pb(Ⅱ) from landfill leachate using L-serine-modified polyethylene/polypropylene nonwoven fabric synthesized via radiation grafting technique

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Nuclear Science and Techniques 2024年第4期35卷 144-155页

作者： Xin-Xin Feng Cheng Li Xuan-Zhi Mao Wan-Ning ren Yang Gao Yu-Long He zhe Xing Rong Li Guo-Zhong Wu Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China

In this study,to efficiently remove Pb(Ⅱ) from aqueous environments,a novel L-serine-modified polyethylene/polypropylene nonwoven fabric sorbent(NWF-serine)was fabricated through the radiation grafting of glycidyl methacrylate and subsequent L-serine *** effect of the absorbed dose was investigated in the range of 5–50 ***-serine was characterized by Fourier transform infrared spectroscopy,thermogravimetric analysis,and scanning electron *** adsorption tests were conducted to investigate the influences of pH,adsorption time,temperature,initial concentration,and sorbent dosage on the Pb(Ⅱ) adsorption performance of *** results indicated that Pb(Ⅱ) adsorption onto NWF-serine was an endothermic process,following the pseudo-second-order kinetic model and Langmuir isotherm *** saturated adsorption capacity was 198.1 mg/***-serine exhibited Pb(Ⅱ) removal rates of 99.8% for aqueous solutions with initial concentrations of 100 mg/L and 82.1% for landfill leachate containing competitive metal ions such as Cd,Cu,Ni,Mn,and ***,NWF-serine maintained 86% of its Pb(Ⅱ) uptake after five use *** coordination of the carboxyl and amino groups with Pb(Ⅱ) was confirmed using X-ray photoelectron spectroscopy and extended X-ray absorption fine structure analysis.

关键词： Landfill leachate Radiation grafting Polyethylene/polypropylene nonwoven fabric Pb(Ⅱ)removal

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煤矿智能化掘进关键技术研究与应用

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机械管理开发 2025年第1期40卷 292-293页

作者：霍国存闫哲霍丽萍任凌杰贾建强山煤国际能源集团股份有限公司物资采购分公司山西太原030000 山西同文职业技术学院山西介休032000

对悬臂式掘进机进行智能化掘进关键技术研究,将掘锚探系统融合,集成创新出一种新型悬臂式掘、护、锚、探一体机,具备高精度导航、自动截割等功能,提升掘进工作面的智能化水平,促进企业高质量发展。

关键词：悬臂式掘进机智能化导航定位截割

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Hyaluronic acid-curcumin conjugate suppresses the fibrotic functions of myofibroblasts from contractive joint by the PTGER2 demethylation

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Regenerative Biomaterials 2019年第5期6卷 269-277页

作者： Dongjie Yu Ze Zhuang Jianhua ren Xuefeng Hu zhe Wang Jieyu Zhang Yuansen Luo Kun Wang Ronghan He Yunbing Wang Department of Orthopedic Surgery The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhou 510000China National Engineering Research Center for Biomaterials Sichuan UniversityChengdu 610000China

Joint contracture is a fibrotic complication induced by joint immobilization and trauma,which is characterized as excessive myofibroblast proliferation in joint *** treatments of joint contracture are unsatisfied and patients are suffered from joint *** previous study has shown that curcumin can inhibit myofibroblast proliferation in vitro,but the major challenge is the low aqueous solubility and biological activity of *** this study,hyaluronic acid-curcumin(HA-Cur)conjugate was synthesized to suppress myofibroblasts in joint *** were isolated from the joint capsules of joint contracture patients and induced to active myofibroblasts by transforming growth factor-b(TGF-b).The anti-fibrotic function and mechanisms of HA-Cur were investigated by immunohistochemistry,reverse transcription-quantitative polymerase chain reaction(PCR),methylation-specific PCR,western blot,transwell migration assay and proliferation *** showed that 30 lM HA-Cur significantly attenuated the fibrotic functions of myofibroblast in joint contracture in vitro by regulating the methylation of prostaglandin E receptor 2(PTGER2)and inhibiting TGF-b *** may provide a mechanism for the treatment of joint contracture,and provide a molecular target PTGER2 for therapy during the pathogenesis of joint contracture.

关键词： curcumin PTGER2 methylation joint contracture

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Mechanisms of fracture propagation from multi-cluster using a phase field based HMD coupling model in fractured reservoir

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Petroleum Science 2024年第3期21卷 1829-1851页

作者： Yun-Jin Wang Bo Wang Hang Su Tu Chang ren-Cheng Dong Li-zhe Li Wei-Yu Tang Ting-Xue Jiang Fu-Jian Zhou State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum-BeijingBejing2249China China University of Petroleum-Beijing at Karamay Karamay834000XinjiangChina China National Oil and Gas Exploration and Development Corporation Ltd. Beijing100034China University of Texas at Austin United States SINOPEC Research Institute of Petroleum Engineering Beijing100101China

Natural fractures(NFs)are common in shale and tight reservoirs,where staged multi-cluster fracturing of horizontal wells is a prevalent technique for reservoir *** NFs and stress interference are recognized as significant factors affecting hydraulic fracture(HF)propagation,the combined influence of these factors remains poorly *** address this knowledge gap,a novel coupled hydromechanical-damage(HMD)model based on the phase field method is developed to investigate the propagation of multi-cluster HFs in fractured *** comprehensive energy functional and control functions are established,while incorporating dynamic fluid distribution between multiple perforation clusters and refined changes in rock mechanical parameters during hydraulic *** HMD coupled multi-cluster HF propagation model investigates various scenarios,including single HF and single NF,reservoir heterogeneity,single HF and NF clusters,and multi-cluster HFs with NF *** results show that the HMD coupling model can accurately capture the impact of approach angle(θ),stress difference and cementation strength on the interaction of HF and *** criterion of the open and cross zones is not *** NF angle(a)is not a decisive parameter to discriminate the *** to the relationship between approach angle(θ)and NF angle(a),the contact relationship of HF can be divided into three categories(θ=a,θa).The connected NF can increase the complexity of HF by inducing it to form branch fracture,resulting in a fractal dimension of HF as high as2.1280 at angles of±45°.Inter-fracture interference from the heel to the toe of HF shows the phenomenon of no,strong and weak ***,under the influence of NFs,distant HFs from the injection can become dominant ***,as a gradually increases,inter-fracture stress interference becomes the primary factor influencing HF propagation,gradually superseding the dominance of NF

关键词： HMD coupling Phase field Natural fracture Flow distribution Hydraulic fracturing Inter-fracture interference

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Protective performance of shear stiffening gel-modified foam against ballistic impact:Experimental and numerical study

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Defence Technology（防务技术） 2024年第2期32卷 510-520页

作者： Huan Tu Haowei Yang Pengzhao Xu zhe Yang Fan Tang Cheng Dong Yuchao Chen Lei ren Wenjian Cao Chenguang Huang Yacong Guo Yanpeng Wei Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Mechanical Engineering Northwestern Polytechnical UniversityXi'an 710072China Xi'an Institute of Electromechanical Information Technology Xi'an 710065China Science and Technology on Transient Impact Laboratory Beijing 102202China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China

As one of the most widely used personal protective equipment(PPE),body armors play an important role in protecting the human body from the high-velocity impact of bullets or *** body torso and critical organs of the wear may suffer severe behind-armor blunt trauma(BABT)even though the impactor is stopped by the body armor.A type of novel composite material through incorporating shear stiffening gel(STG)into ethylene-vinyl acetate(EVA)foam is developed and used as buffer layers to reduce *** this paper,the protective performance of body armors composed of fabric bulletproof layers and a buffer layer made of foam material is investigated both experimentally and *** effectiveness of STG-modified EVA in damage relief is verified by ballistic *** parallel with the experimental study,numerical simulations are conducted by LS-DYNA®to investigate the dynamic response of each component and capture the key mechanical parameters,which are hardly obtained from field *** fully describe the material behavior under the transient impact,the selected constitutive models take the failure and strain rate effect into consideration.A good agreement between the experimental observations and numerical results is achieved to prove the validity of the modelling *** tests and simulations show that the impact-induced deformation on the human body is significantly reduced by using STG-modified EVA as the buffering *** improvement of protective performance is attributed to better dynamic properties and more outstanding energy absorption capability of the composite foam.

关键词： Ballistic behavior Composite foam Shear stiffening gel Finite element analysis Protective mechanism

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Alleviating effects and mechanisms of action of large-leaf yellow tea drinking on diabetes and diabetic nephropathy in mice

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Food Science and Human Wellness 2023年第5期12卷 1660-1673页

作者： Guangshan Zhao Jianyuan Teng Ruixia Dong Qiuyan Ban Lian Yang Kang Du Yifei Wang Hanlin Pu Chung S.Yang zhe ren Innovation Team of Food Nutrition and Safety Control College of Food Science&TechnologyHenan Agricultural UniversityZhengzhou 450002China Biology Postdoctoral Research Station Department of Cell BiologyCollege of Life Science and TechnologyJinan UniversityGuangzhou 510632China College of Horticulture Jinling Institute of TechnologyNanjing 211169China Department of Forestry and Technology Lishui Vocational and Technical CollegeLishui 323000China Department of Tea Science College of HorticultureHenan Agricultural UniversityZhengzhou 450002China Guangdong Provincial Engineering Center of Topical Precise Drug Delivery System School of PharmacyGuangdong Pharmaceutical UniversityGuangzhou 510006China Department of Chemical Biology Ernest Mario School of PharmacyRutgersThe State University of New JerseyPiscataway 08901USA International Joint Research Laboratory of Tea Chemistry and Health Effects Anhui Agricultural UniversityHefei 230036China

Our previous study found that large-leaf yellow tea(LYT)had interesting hypoglycemic activity in high-fat diet-induced obese mice and highly safety in healthy mice. To study the anti-diabetic potential of LYT, the present study further investigated the preventive effects and mechanisms of action of LYT administration on diabetes and diabetic nephropathy in high-fat diet plus streptozotocin-induced diabetic mice. Results showed that LYT infusions(1/100 and 1/50, m/V)as drinking fluid for 4 weeks reduced diabetic polydipsia and polyuria, enhanced glucose tolerance and insulin sensitivity, and lowered fasting blood glucose level. The underlying mechanisms involve downregulation of gluconeogenesis(lower protein levels of TXNIP and FBP and enzyme activity of FBP), upregulation of lipid catabolism(higher protein levels of CPT-1α and PPARα), downregulation of lipogenesis(lower protein level of SREBP-1), and modification of the structure and abundance of gut microbiota to modulate metabolic homeostasis. Moreover, LYT administration prevented diabetic nephropathy, possibly due to reduced glucose-caused osmotic diuresis and lowered levels of renal PKC-β2, NLRP3 as well as membrane PKC-α, AQP2 and glycosylated AQP2 proteins. Taken together, LYT exhibits the activities in alleviating diabetic symptoms, ameliorating glucose and lipid dysmetabolism and fatty liver, and preventing diabetic nephropathy in diabetic mice. These activities may be explored for the prevention and treatment of diabetes in humans.

关键词： Diabetes Glucose and lipid metabolism Gut microbiota Diabetic nephropathy Large-leaf yellow tea

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预合金化工艺对铝脱氧钢洁净度的影响

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钢铁 2025年第1期60卷 51-65页

作者：程林王哲胡志远任强张立峰燕山大学材料工程学院河北秦皇岛066044 燕山大学机械工程学院河北秦皇岛066044 首钢智新电磁材料(迁安)股份有限公司河北迁安064404 北方工业大学机械与材料工程学院北京100144

低碳铝镇静钢的脱氧方式主要为铝脱氧,而钢液中不同异质成核位点的出现会对后续脱氧产物的形核生长产生影响。通过实验室试验对铝镇静钢的预合金化工艺进行了研究,使用酸溶法和电解法对钢中夹杂物的三维形貌及数量进行了表征。热力学计... 详细信息

低碳铝镇静钢的脱氧方式主要为铝脱氧,而钢液中不同异质成核位点的出现会对后续脱氧产物的形核生长产生影响。通过实验室试验对铝镇静钢的预合金化工艺进行了研究,使用酸溶法和电解法对钢中夹杂物的三维形貌及数量进行了表征。热力学计算以及试验表明,添加1.0%A(l质量分数)时钢液进行的复合脱氧处理中热力学稳定相为Al_(2)O_(3)相,不同脱氧工艺之间的差异体现在钢液成分和夹杂物形貌上。通过铝氧反应试验讨论了不同预合金化工艺对铝脱氧形成Al_(2)O_(3)夹杂物的形核、生长、形貌、尺寸及数量的影响,发现在实验室试验条件下,钢液中Al_(2)O_(3)夹杂物主要有球状、树枝状、多边形块状和团簇状4大类形貌。预先存在FeO的铝氧反应主要涉及Al_(2)O_(3)夹杂物形核析出阶段、形貌演化阶段和团聚烧结阶段。其余铝氧反应在反应初期涉及不同夹杂物改性过程。粗糙界面局部过饱和度较高时容易形成球状形貌且不易成簇。界面局部过饱和度较低时容易形成刻面形貌,局部氧过饱和度较高时容易形成树枝状形貌,随着氧过饱和度的降低会逐渐向花瓣状、片层状和板条状演变。预先存在SiO2夹杂物的铝氧反应中夹杂物的数密度最高,其平均三维尺寸最低。钢液中Al_(2)O_(3)夹杂物的形貌会受到预先存在的夹杂物、过饱和度、脱氧剂和溶解氧、过冷度、结构的影响。

关键词：预合金化工艺铝镇静钢夹杂物形貌演变过饱和度铝氧反应低碳钢液脱氧剂

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Reliability study of custom designed ADC for the Jiangmen underground neutrino observatory

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Radiation Detection Technology and Methods 2020年第2期4卷 203-207页

作者： Ru-yi Jin Jun Hu Jia-yi ren zhe Ning Xiao-shan Jiang State Key Laboratory of Particle Detection and Electronics Institute of High Energy PhysicsChinese Academy of Sciences(CAS)Beijing 100049China University of Chinese Academy of Sciences(UCAS) Beijing 100049China

Objective The Jiangmen underground neutrino observatory(JUNO)is the largest and most precise liquid scintillator detector under construction in the south of *** front-end readout electronics system will be installed very close to the photomultiplier tubes under ***,the system’s absolute reliability is *** an important piece,the failure rate of the custom designed analog-to-digital convertor(ADC)must be *** The Arrhenius High Temperature Operating Life(HTOL)model is usually used to calculate the standard reliability value failure rate(λ).A temperature acceleration test of the ADC is performed with a 115℃ambient temperature based on a custom aging *** performance of ADC is compared before and after aging,and the most significant bit(MSB)of the digital output is monitored during the *** The result of a 2400-hour-long test shows that there were no *** upper limit of the failure rate is calculated as 5.8FIT,which can be added to the failure rate of other components to meet the overall failure rate requirements(84FIT).Conclusion With the test system,we established a method based on the HTOL model to obtain the upper limit of the ADC reliability for overall failure rate calculation in *** method can be applied to the reliability measurement for any other custom designed *** experiment can be repeated with a new set of parameters to get a satisfactory failure rate according to other overall system requirements.

关键词： ADC Reliability HTOL Failure rate

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