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Research,application and development of inorganic binder for casting process

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China Foundry 2024年第5期21卷 461-475页

作者： Xiao-long Gong sheng-li Hu Zi-tian Fan State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

Inorganic binder used in casting process has the advantages of low odor,labor-friendly conditions,and relatively low cost,which is one of the main development directions for casting molding materials in the ***,compared to organic binders(such as resin binders),inorganic binders exhibit lower bonding strength and are more sensitive to environmental *** sensitivity poses challenges,particularly in the reclamation of used sand,thus limiting their broader *** this paper,the research and application status of inorganic binders(mainly silicate inorganic binders)and their curing methods are *** addition,the research and application of phosphate inorganic binders and 3D printing inorganic binders that are being developed are ***,a detailed comparative analysis is conducted on the challenging issue of“reclamation for used sand”in the application of inorganic ***,the development direction of inorganic binders is clarified.

关键词： inorganic binder silicate system phosphate system 3D printing used sand reclamation development trend

Snowpack variations and their hazardous effects under climate warming in the central Tianshan Mountains

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Advances in Climate Change Research 2024年第3期15卷 442-451页

作者： Jian-sheng HAO Yan WANG Lan-Hai li Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences(CAS)Beijing 100101China Xinjiang Key Laboratory of Water Cycle and Utilization in Arid Zone Urumqi 830011China State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Tianshan Snowcover and Avalanche Observation and Research Station of Xinjiang Xinyuan 835800China CAS Research Center for Ecology and Environment of Central Asia Urumqi 830011China

Climate change alters snowpack evolution,which in turn influences the likelihood of snow avalanches and flood *** lack of systemic observational data on key snow characteristics in high mountains remains a scientific challenge in terms of systematically elucidating the dynamic chain of variations in climate-snowpack-snow *** restricts our understanding and poses challenges in the prediction of snow-related disaster *** such,this study analysed the variations of temperature and snowfall and the physical characteristics of snowpacks based on ground-based observations from the Kunse River Valley situated in the Tianshan Mountains from 1967 to *** results reveal that the temperature increased significantly by 0.32°C per decade(plier ***,average and maximum snow depths increased along with an increase in peak snow water equivalent,thus indicating a higher frequency of extremely scarce or abundant snow *** low snowpack temperature gradient and earlier snowmelt dates in spring lead to earlier occurrences of snowmelt floods and wet *** the risks of these events increase,they pose greater threats to farmlands,road transportation,water-electricity infrastructure and several other human ***,these insights are critical for providing vital information that can deepen our understanding of the impact of climate change on snowpack characteristics and improve management strategies for snow-related disaster prevention and mitigation.

关键词： Climate change Snowpack variations Snow-related disaster Tianshan Mountains

一种用于重力测量信号畸变校正的盲反卷积算法(英文)

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中国惯性技术学报 2015年第2期23卷 196-200页

作者：赵立业李宏生微惯性仪表与先进导航技术教育部重点实验室南京210096 东南大学仪器科学与工程学院南京210096

强阻尼和大时间常数是海洋重力仪的共同特性,它们在抑制垂直方向上干扰加速度的同时也造成了重力仪测量信号的幅值衰减和相位滞后。为了校正重力测量信号的畸变,获得高精度的重力异常信号,在分析重力仪和重力测量信号畸变原理的基础上,... 详细信息

强阻尼和大时间常数是海洋重力仪的共同特性,它们在抑制垂直方向上干扰加速度的同时也造成了重力仪测量信号的幅值衰减和相位滞后。为了校正重力测量信号的畸变,获得高精度的重力异常信号,在分析重力仪和重力测量信号畸变原理的基础上,提出了一种单通道Bussgang算法,并应用于重力测量信号的畸变校正。该方法首先将盲反卷积滤波器近似简化为FIR模型,然后采用常数恒模算法对Bussgang均衡器权系数进行更新,并在此基础上对反卷积滤波器进行了估计,最后基于实测重力信号将该方法与Kalman逆滤波进行了试验对比。理论分析和试验结果表明,该重力信号畸变校正方法能有效地消除重力测量信号的畸变,且校正效果明显优于Kalman逆滤波,其校正后信号相对于原始信号的标准差为0.328×10-5 m/s2,而Kalman逆滤波校正标准差为1.838×10-5 m/s2。

关键词：重力仪重力异常 Bussgang反卷积算法 Kalman逆滤波畸变校正

Solvent-free carbon sphere nanofluids towards intelligent lubrication regulation

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Friction 2024年第1期12卷 95-109页

作者： sheng ZHANG Wen li Xiaoliang MA Xiaoqiang FAN Minhao ZHU Tribology Research Institute School of Mechanical EngineeringSouthwest Jiaotong UniversityChengdu 610031China Key Laboratory of Advanced Technologies of Materials Ministry of EducationSchool of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China

By simply switching the electrical circuit installed on steel/steel contact,the tribological behaviors of nanofluids(NFs)can be regulated in real time,thereby achieving the desired performance of friction reduction and wear ***,solvent-free carbon spherical nanofluids(C-NFs)were successfully prepared for intelligent lubrication regulation.C-NFs with excellent lubrication performance can immediately reduce the coefficient of friction(COF)despite applying a weak electric potential(1.5 V).Moreover,polyethylene glycol 400(PEG400)containing 5.0 wt%C-NFs remained responsive to electrical stimulation under the intermittent voltage application with an average coefficient of friction(ACOF)reduction of 20.8%over *** intelligent lubrication regulation of C-NFs under an external electric field(EEF)mainly depends on the orderly arranged double-electric adsorption film of ion canopy-adsorbed carbon spheres(CSs).The intermittent electrical application can continuously reinforce the adsorption film and its durability for real-time controlling the sliding ***-stimulation-responsive intelligent lubricants provide a new technical support for realizing intelligent stepless control of devices.

关键词： solvent-free carbon spherical nanofluids(C-NFs) intelligent lubrication regulation lubrication performance adsorption film

A CSMA/CA based MAC protocol for hybrid Power-line/Visible-light communication networks:Design and analysis

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Digital Communications and Networks 2024年第2期10卷 481-497页

作者： sheng Hao Huyin Zhang Fei Yang Chenghao li Jing Wang School of Computer Science Central China Normal UniversityWuhan430079PR China Hubei Key Laboratory of intelligent Robot(Wuhan Institute of Technology) Wuhan430079PR China School of Computer Science Wuhan UniversityWuhan430079China School of Information Science and Engineering Shandong Normal UniversityJinan250000China School of Computer Science Hubei University of TechnologyWuhan430079China

Hybrid Power-line/Visible-light Communication(HPVC)network has been one of the most promising Cooperative Communication(CC)technologies for constructing Smart Home due to its superior communication reliability and hardware *** research on HPVC networks focuses on the performance analysis and optimization of the Physical(PHY)layer,where the Power line Communication(PLC)component only serves as the backbone to provide power to light Emitting Diode(LED)*** designing a Media Access Control(MAC)protocol remains a great challenge because it allows both PLC and Visible light Communication(VLC)components to operate data transmission,i.e.,to achieve a true HPVC network *** solve this problem,we propose a new HPC network MAC protocol(HPVC MAC)based on Carrier Sense Multiple Access/Collision Avoidance(CSMA/CA)by combining IEEE 802.15.7 and IEEE 1901 ***,we add an Additional Assistance(AA)layer to provide the channel selection strategies for sensor stations,so that they can complete data transmission on the selected channel via the specified CSMA/CA mechanism,*** on this,we give a detailed working principle of the HPVC MAC,followed by the construction of a joint analytical model for mathematicalmathematical validation of the HPVC *** the modeling process,the impacts of PHY layer settings(including channel fading types and additive noise feature),CSMA/CA mechanisms of 802.15.7 and 1901,and practical configurations(such as traffic rate,transit buffer size)are comprehensively taken into ***,we prove the proposed analytical model has the ***,through extensive simulations,we characterize the HPVC MAC performance under different system parameters and verify the correctness of the corresponding analytical model with an average error rate of 4.62%between the simulation and analytical results.

关键词： Hybrid power-line/Visible light communication (HPVC)networks MAC protocol CSMA/CA IEEE 802.15.7 IEEE 1901 Performance analysis

Stochastic uncertain lubrication in gear transmission subjected to tribodynamic loading

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Friction 2024年第8期12卷 1741-1756页

作者： Zhou CHEN Haiming SHA sheng li Zheming TONG Shuiguang TONG State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China School of Mechanical Engineering Zhejiang UniversityHangzhou 310027China Wright State University 3640 Colonel Glenn HighwayDaytonOH 45435USA

A stochastic uncertain tribodynamic model is established for a spur gear pair for the first *** stochastic uncertainty of pinion rotation speed propagated to lubrication performance is *** probability density function of the minimum lubricant film thickness hmin evolves over time periodically at interval of an engagement *** between abrupt increase in meshing force and amplification of hmin uncertainty is *** and reliable lubrication performance can be achieved by suppressing the hmin uncertainty and decreasing the lubrication failure *** can be done by increasing lubricant viscosity,and decreasing input torque and uncertainty level of input rotation *** work lays a solid foundation for robust and reliability based optimization for tribodynamic gear system.

关键词： stochastic uncertainty gears elastohydrodynamic lubrication(EHL) tribodynamics

Enhanced hydrogen evolution reaction in FePt film with remanence due to decrease in domain walls

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Rare Metals 2024年第3期43卷 1108-1115页

作者： hong hong Dong-Xue liu Jun li Jun-Ming li li-Qian Wu Bo Yang Qing-Qi Cao Dun-Hui Wang National Laboratory of Solid State Microstructures Collaborative Innovation Center of Advanced MicrostructuresJiangsu Provincial Key Laboratory for NanotechnologySchool of PhysicsNanjing UniversityNanjing210093China Hangzhou Dianzi University Hangzhou310018China Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Material Science and EngineeringNortheastern UniversityShenyang110819China

As an effective strategy to improve the properties of electrocatalysts,magnetic field-assisted electrocatalytic water splitting has attracted increasing attention ***,the corresponding enhancements mostly depend on the exertion of an external magnetic field during electrochemical reactions,which results in a high cost of industrial production,and makes the magnetic field manipulation of electrocatalysis become a challenging *** this work,instead of the external magnetic field,a bias magnetic field is self-supplied by the remanence state of a ferromagnetic electrocatalyst of *** to the assistance of this bias magnetic field,the FePt film in the remanence state shows the overpotential of 229 mV during hydrogen evolution reaction,which is much lower than that in its demagnetization state(283 mV).Our findings demonstrate that the remanence in ferromagnetic electrocatalysts can improve the catalytic performance,which is attributed to the decrease in domain walls.

关键词： Remanence Magnetic domains Electrocatalysis Hydrogen evolution reaction(HER)

Diagnosis and surgical treatment of pancreatic endocrine tumors in 36 patients:a single-center report

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Chinese Medical Journal 2007年第17期120卷 1487-1490页

作者： liU hong ZHANG Su-zhan WU Yu-lian FANG He-qing li Jiang-tao sheng hong-wei WANG Yong Department of Surgery Second Affiliated Hospital ZhejiangUniversity School of Medicine Hangzhou 310006 China

Background Pancreatic endocrine tumors （PETs） are rare and their surgical treatment is often debated. The purpose of this retrospective study was to analyze the diagnosis and surgical strategy of functioning and non-functioning PETs. Methods From May 1980 to March 2006, 36 patients with pancreatic endocrine tumors at the Second Affiliated Hospital of Zhejiang University were retrospectively studied. Results Among the 36 patients, 29 （81%） had functioning tumors, and 7 （19%） had nonfunctioning tumors. Ninety-two percent of insulinomas were benign, whereas 4 （57%） of nonfunctioning PETs were malignant. The size of functioning tumors was （2.3i-0.3） cm, that of nonfunctioning tumors was less than （5.1^-0.5） cm. The combination CT and transabdominal ultrasonography resulted in a diagnostic sensitivity of 84%. Thirty-three primary lesions were precisely located in 32 patients （89%）. Atypical tumor resection was performed for 73% of functioning tumors, while typical pancreatectomy was performed for 6 （85%） of nonfunctioning tumors. Moreover, 5 liver resections and 1 lymph node dissection were performed. During the follow-up, fifteen complications occurred in 12 （36%） patients after operation. The 5-year survival rate for patients with benign tumors was 92% compared to 50% for those with malignant tumors. Surgical cure was achieved in 95% of patients with benign insulinomas. Conclusions Surgical strategy for PETs depends on the size and location of the tumor and the risk of malignancy. The optimal surgical procedure is key to prevent postoperative complication. Radical resection including initial and metastatic lesion may benefit patients with maliqnant PETs.

关键词： pancreatic endocrine tumor, insulinoma diagnosis surgery

Pathological diagnosis and immunohistochemical analysis of giant retrosternal goiter in the elderly: A case report

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World Journal of Clinical Cases 2024年第3期12卷 643-649页

作者： Yong-Chang Meng liu-sheng Wu Ning li hong-Wei li Jing Zhao Jun Yan Xiao-Qiang li Peng li Jiang-Qi Wei Department of Cardiothoracic Surgery Xinxiang First People's HospitalXinxiang 453000Henan ProvinceChina School of Clinical Medicine Tsinghua UniversityBeijing 100084China Graduate School Qinghai UniversityXining 810016Qinghai ProvinceChina Department of Pathology Xinxiang First People's HospitalXinxiang 453000Henan ProvinceChina Department of Thoracic Surgery Peking University Shenzhen HospitalShenzhen 518036Guangdong ProvinceChina

BACKGROUND Elderly giant retrosternal thyroid goiter is a rare yet significant medical condition,often presenting clinical symptoms that can be confused with other diseases,posing diagnostic and therapeutic *** study aims to delve into the characteristics and potential mechanisms of this ailment through pathological diagnosis and immunohistochemical analysis,providing clinicians with more precise diagnostic and treatment strategies.A 77-year-old male,was admitted to hospital with the chief complaint of finding a goiter in the semilunar month during physical examination,accompanied by *** protruding into the superior mediastinum,the adjacent structure was compressed,the trachea was compressed to the right,and the local lumen was slightly *** patient was diagnosed with giant retrosternal *** dyspnea caused by trachea compression,our department planned to perform giant retrosternal *** results:Tg(+),TTF-1(+),Calcitonin(CT)(I),Ki-67(+,about 20%),CD34(-).Retrosternal goiter means that more than 50%of the volume of the thyroid gland is below the upper margin of the *** retrosternal goiter disease is a relatively rare disease,once the disease is diagnosed,it should be timely surgical treatment,and the treatment is more difficult,the need for professional medical team for comprehensive *** The imaging manifestations of giant retrosternal goiter are atypical,histomorphology and immunohistochemistry can assist in its *** article reviews the relevant literature of giant retrosternal goiter immunohisto-chemistry and shows that giant retrosternal goiter is positive for Tg,TTF-1,and Ki-67.

关键词： Giant retrosternal goiter Pathology Immunohistochemistry Case report