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Effect of yttrium substitution on magnetic properties and service performances of Nd-Fe-B sintered magnets

Journal of Rare Earths 2023年第1期41卷 116-121页

作者： Xiaodong Fan shuai guo Guangfei Ding Sining Fan Zhehuan Jin Renjie Chen Shukai Zhang Aru Yan CAS Key Laboratory of Magnetic Materials and Devices Ningbo Institute of Material Technology and EngineeringChinese Academy of SciencesNingbo 315201China Chinalco Shandong Yinuowei Strong Magnetic Material Co. LtdTaian 271600China

We successfully fabricated partial Y substituted NdY-Fe-B magnets with nominal compositions of(Nd_(1-x)Y_(x))_(13.80)Fe_(ba1)Al_(0.24)Cu_(0.1)B_(6.04)(at%,x=0,0.1,0.2,0.3,0.4) by powder metallurgy process and the magnetic properties as well as service performances of the magnets were also systematically *** phase constituents of the magnets have no obvious variation within the whole range of Y content,while the main phase grains form in-situ core-shell structure where Y gathers in the core and Nd mainly distributes in the *** with pure Nd-Fe-B magnets,the magnetic performances of Y substituted magnets slightly decrease on account of the poor intrinsic magnetic properties of Y_(2)Fe_(14)***,the μ_(O)M_(r),μ_(O)H_(cj) and(BH)_(max) of the 20 at% Y magnet still remain at a high level of 1.325 kG,1.173 kOe and 342.884 kj/m^(3),which approaches the performances of commercial N45-grade *** service performances of Y substituted magnets indicate that though the surface corrosion products and Vickers hardness of the NdY-Fe-B magnets increase to a certain extent compared to Nd-Fe-B,the magnets with Y substitution still display relatively good service ***,on the basis of sacrificing little partial magnetic and service performances,Y substituted Nd can still prepare NdY-Fe-B medium-grade *** this way,we achieve the balanced utilization of rare earth resources,which has significant meanings for the industry and scientific research.

关键词： Y substitution Magnetic properties Service performances Nd-Fe-B sintered Magnets Rare earths

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Effects of Nd-Ga intergranular addition on microstructure and magnetic properties of heavy-rare-earth-free Nd-Fe-B sintered magnets

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Journal of Rare Earths 2022年第6期40卷 924-929,I0003页

作者： Jinhao Zhu Guangfei Ding Lei Jin Zhehuan Jin Bo Zheng shuai guo Renjie Chen Aru Yan CAS Key Laboratory of Magnetic Materials and Devices and Zhejiang Province Key Laboratory of Magnetic Materials and Application TechnologyNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China University of Chinese Academy of Sciences Beijing 100049China

In this study,we propose an approach of grain boundary modification that can significantly increase the coercivity of the B-lean Nd-Fe-B sintered magnets by intergranular addition of *** coercivity is substantially enhanced from 1.51 to 2.04 T through optimizing the microstructure and adjusting the phase composition for the grain boundary phase in the annealed *** matrix grains are covered by a continuous thin grain boundary phase accompanying the formation of intermetallic Nd_(6)Fe_(13)Ga *** analysis of magnetic behaviors above Curie temperature confirms that the grain boundary phase of annealed Nd-Ga doped magnets appears to be non-ferromagnetic,facilitating the intergrain exchange *** observation in grain boundary area indicates that some surface of the matrix grain is dissolved in the formation process of the Nd_(6)Fe_(13)Ga *** gives rise to a decrease in the proportion of matrix grains and saturation magnetization of the *** detailed relationship between magnetic properties and microstructure is discussed based on these results.

关键词： Nd-Fe-B sintered Magnet Magnetic properties Grain boundary Microstructures Rare earths

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Settlement prediction model of slurry suspension based on sedimentation rate attenuation

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Water Science and Engineering 2012年第1期5卷 79-92页

作者： shuai-jie guo Fu-hai ZHANG Bao-tian WANG Chao ZHANG Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing 210098P.R.China Institute of Geotechnical Engineering Hohai UniversityNanjing 210098P.R.China Bureau of Hydrology Changjiang Water Resources CommissionWuhan 430012P.R.China

This paper introduces a slurry suspension settlement prediction model for cohesive sediment in a still water environment. With no sediment input and a still water environment condition, control forces between settling particles are significantly different in the process of sedimentation rate attenuation, and the settlement process includes the free sedimentation stage, the log-linear attenuation stage, and the stable consolidation stage according to sedimentation rate attenuation. Settlement equations for sedimentation height and time were established based on sedimentation rate attenuation properties of different sedimentation stages. Finally, a slurry suspension settlement prediction model based on slurry parameters was set up with a foundation being that the model parameters were determined by the basic parameters of slurry. The results of the settlement prediction model show good agreement with those of the settlement column experiment and reflect the main characteristics of cohesive sediment. The model can be applied to the prediction of cohesive soil settlement in still water environments.

关键词： cohesive sediment sedimentation rate attenuation slurry suspension settlement prediction model settlement column experiment

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A comparative study of NdY-Fe-B magnet and NdCe-Fe-B magnet

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Journal of Rare Earths 2022年第9期40卷 1480-1487,I0006页

Low cost and high abundance rare earth elements Y and Ce have attracted tremendous interests of the industrial and scientific societies for fabricating the highly cost-performance efficient rare earth permanent ***,the effect of separate replacement of Nd by Y or Ce on the performances of NdFeB-type magnet under the same atomic ratio and preparation conditions is still *** this work,we systematically investigated the magnetic properties,thermal stabilities and service performances of(Nd_(0.8)Y_(0.2))_(13.80)Fe_(bal)Al_(0.24)Cu_(0.1)B_(6.04)(atomic fraction,denoted as 20 Y)and(Nd_(0.8)Ce_(0.2))_(13.80)Fe_(bal)Al_(0.24)Cu_(0.1)B_(6.04)(atomic fraction,denoted as 20 Ce)*** results demonstrate that theμ_(0)M_(r),μ_(0)H_(c)and(BH)_(max)of 20 Y magnet are respectively 1.325 T,1.173 T and 343.467 kJ/m^(3),which are comprehensively higher than those of 20 Ce magnet(μ_(0)M_(r)=1.310 T,μ_(0)H_(c)=0.948 T,(BH)_(max)=321.105 kJ/m^(3)).Moreover,the 20 Y magnet has higher thermal stability compared with 20 Ce magnet which is favorable for the magnetic performances at elevated *** investigation of micro structure and elemental distribution indicates that the excellent magnetic performance s of NdY-Fe-B magnet can be attributed not only to the preferable intrinsic properties4πM_(s),H_(s)and T_(c)of Y_(2)Fe_(14)B,but also to the in-situ co re-shell structure of the 2:14:1 matrix phase grain with Yrich core and Nd-rich shell,along with the thicker grain boundary layer between the adjacent matrix phase grains in NdY-Fe-B ***,the 20 Y magnet exhibits better mechanical property and higher corrosion resistance than 20 Ce magnet,which are helpful for prolonging the service life of the magnet in practical application.

关键词： NdY-Fe-B NdCe-Fe-B Magnetic properties Thermal stabilities Service performances Rare earths

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High-throughput genotyping of single-nucleotide polymorphisms in ace-1 gene of mosquitoes using MALDI-TOF mass spectrometry

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Insect Science 2013年第2期20卷 167-174页

作者： Yun Mao Feng Tan shuai-guo Yan guo-Xing Wu Chuan-Ling Qiao Wen-Xue Zhang Feng Cui College of Life Sciences Henan Normal University Xinxiang Henan Province State Key Laboratory of Integrated Management of Pest Insects & Rodents Institute of Zoology Chinese Academy of Sciences Beijing College of Plant Protection Yunnan Agricultural University Kunming China

Acetylcholinesterase （ACHE） plays a vital role in the nervous system of insects and other animal species and serves as the target for many chemical agents such as organophosphate and carbamate insecticides. The mosquito, Culex pipiens complex, a vector of human disease, has evolved to be resistant to insecticides by a limited number of amino acid substitutions in ACHE1, which is encoded by the ace-1 gene. The aims of this study are to identify single nucleotide polymorphism （SNP） sites in the ace-1 gene of the C. pipiens complex and explore an economical high-throughput method to differentiate the genotypes of these sites in mosquitoes collected in the field. We identified 22 SNP sites in exon regions of the ace-1 gene. Four of them led to non-synonymous mutations, that is, Y163C, G247S, C677S and T682A. We used matrix-assisted laser desorption ionization - time-of-flight mass spectrometry for genotyping at these four sites and another site F416V, which was relevant to insecticide resistance, in 150 mosquitoes collected from 15 field populations. We were able to synchronize analysis of the five SNP sites in each well of a 384-well plate for each individual mosquito, thus decreasing the cost to one-fifth of the routine analysis. Heterozygous genotypes at Y163C and G247S sites were observed in one mosquito. The possible influence of the five SNP sites on the activity or function of the enzyme is discussed based on the predicted tertiary structure of the enzyme.

关键词： acetylcholinesterase genotype insecticide resistance MassArray SNP

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Single-atom catalysis for advanced oxidation and reduction systems in water decontamination

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Rare Metals 2024年第8期43卷 3576-3606页

作者： Jie Teng Jin-Hui Xu Wen-Xin Sun Xue-Feng Liu Xia Xu guo-shuai Liu School of Urban Construction Changzhou UniversityChangzhou 213164China School of Environmental and Civil Engineering Jiangnan UniversityWuxi 214122China

Water scarcity is an escalating global crisis,posing a severe threat to populations ***,exploring various materials to remove emerging contaminants from freshwater sources has garnered significant *** this regard,single-atom catalysis(SACs) has emerged as a catalyst of scientific progress in water purification and treatment methodologies during recent *** exhibit exceptional catalytic activity,selectivity and stability,due to their near-perfect atom utilization,highly unsaturated coordination environment and uniform reaction ***,a comprehensive and critical review encompassing the successful integration of SACs into water purification processes needs to be *** review aims to accentuate recent trends by presenting the synthesis,structure,and environment and energy application-relevant properties of *** results show that a comprehensive and multi-perspective summary of the advantages of SACs in environmental remediation can have significant benefits,such as fast kinetics,costeffectiveness,*** oxidation and reduction processes of SACs and functional SACs materials in water purification were ***,the last section is devoted to the current research gaps and further perspectives on the application of SACs in water treatment,which are summarized and analyzed.

关键词： Single-atom catalysis Water treatment Oxidation Reduction

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The Development Characteristics and Distribution Predictions of the Paleogene Coal-measure Source Rock in the Qiongdongnan Basin,Northern South China Sea

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Acta Geologica Sinica(English Edition) 2021年第1期95卷 105-120页

作者： WANG Dongdong ZHANG Gongcheng LI Zengxue DONG guoqi SUN Rui guo shuai WU Yue College of Earth Science and Engineering Shandong University of Science and TechnologyQingdaoShandong 266590China CNOOC Research Institute Co. Ltd.Beijing 100028China College of Geoscience and Surveying Engineering China University of Mining and Technology(Beijing)Beijing 100083China

There are known to be enormous Cenozoic coal-type oil and gas resources located in the basins of the South China Sea,among which the Paleogene coal-measure source rock are one of the main source *** order to more effectively analyze the distribution laws of coal-measure source rock in marginal sea basins and guide coal-type oil and gas explorations,the Oligocene coal-measure source rock in the Qiongdongnan Basin were selected as examples in order to systematically analyze the types,development characteristics,control factors,and distribution prediction methods of coalmeasure source rock in marginal sea *** Qiongdongnan Basin is located in the northern region of the South China *** explorations of the area have determined that the Oligocene coal-measure source rock in the Qiongdongnan Basin have typical"binary structures",which include coal seams and terrigenous marine *** those,the terrigenous marine mudstone has been found to greatly expand the scope of the coal-measure source *** addition,the coal seams which have been exposed by drilling have been observed to have the characteristics of thin single layer thickness,many layers,and poor ***,the terrigenous marine mudstone has the characteristics of large thickness and wide *** development of coal-measure source rock is known to be controlled by many factors,such as paleoclimate and paleobotany condition,paleo-structure and topography,paleo-geography,rise and fall of base level,and so *** accordance with the comprehensive analyses of various control factors of coal-measure source rock,and the changes in water body energy in sedimentary environments,a genetic model of the"energy belt"for the development and distribution of coal-measure source rock was ***,the development and distribution characteristics of coalmeasure source rock in different types of energy belts were ***,based on the development and distribution characteristics o

关键词： coal-measure source rock "energy belt"mode Paleogene marginal sea basins Qiongdongnan Basin

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Injection Quantity Control for GDI Engines

Injection Quantity Control for GDI Engines

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第25届中国控制与决策会议

作者： guo shuai XIN Baiyu HU Yunfen CHEN Hong State Key Laboratory of Automotive Simulation and Control Jilin University Department of Control Science and Engineering Jilin University

ISBN: (纸本)9781467355339

To improve fuel economy and reduce emissions, direct injection technology with precise fuel injections is widely used for gasoline engines, because quantitative precise fuel injection, as well as multi injection during one combustion revolution, is fit for the whole engine speed range. This paper designs a PID controller of fuel injection quantity for gasoline direct injection （GDI）. Firstly, a mathematical model of an injector, which is used for controller validation, is established mainly based on fluid dynamic;Secondly, a map of fuel injection quantity corresponding with engine demands （according to engine speed and rail pressure） is calibrated by using the high-fidelity engine software enDYNA through experiments. Then, a PID controller is aimed to track the given value of fuel injection quantity. Tuning controller parameters are chosen by randomized algorithm according to the criteria of performance. Simulation results show that the designed control scheme is effective.

关键词： GDI engine map calibration injection quantity PID controller

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Reservoir forming conditions and key exploration technologies of Lingshui 17-2 giant gas field in deepwater area of Qiongdongnan Basin

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Petroleum Research 2019年第1期4卷 1-18页

作者： Yuhong Xie Gongcheng Zhang Zhipeng Sun Qingbo Zeng Zhao Zhao shuai guo China National Offshore Oil Co. Ltd.Beijing100028China Research Institue Co.Ltd China National Offshore Oil Co.Ltd.Beijing100028China Research Institute of Zhanjiang Branch China National Offshore Oil Co.Ltd.Zhanjiang524057China

On September 15,2014,China National Offshore Oil Co.,Ltd announced that a high production of oil and gas flow of 1.6106 m3/d was obtained in Well LS17-2-1 in deepwater area in northern South China Sea,which is the first great oil and gas discovery for self-run deepwater exploration in China sea areas,and a strategic breakthrough was made in natural gas exploration in deepwater area of Lingshui sag in Qiongdongnan *** the combined action of climax of international deepwater exploration,high oil prices,national demands of China,practical needs of exploration,breakthroughs in seismic exploration and testing technologies,innovations in geological cognition and breakthroughs in deepwater operation equipment,Lingshui 17-2 gas field is *** these factors,the innovation in reservoir forming geological cognition directly promotes the *** quality of seismic data in the early time is poor,so key reservoir forming conditions such as effective source rocks,high quality reservoirs and oil-gas migration pathways are unable to be ascertained;with support of new seismic acquisition and processing technology,some researches show that Lingshui sag is a successive large and deep sag with an area of 5000 km2 and the maximum thickness of Cenozoic stratum of 13 *** the Early Oligocene,the Lingshui sag was a semi-closed delta-estuarine environment,where the coalmeasure and marine mudstones in Lower Oligocene Yacheng Formation were *** Lingshui sag is a sag with high temperature,and the bottom temperature of source rocks in Yacheng Formation can exceed 250C,but the simulation experiment of hydrocarbon generation at high temperature indicates that the main part of this set of source rock is still in the gas-generation window,with resources of nearly 1 trillion cubic meters,so the Lingshui sag is a hydrocarbon-rich generation *** the Neogene,the axial canyon channel from the Thu Bon River in Vietnam passed through the Lingshui sag,and five stages

关键词： Deepwater oil and gas Source rocks Lower limit of gas generation The central canyon Diapiric zone Migration pathway Lingshui sag Lingshui 17-2 giant gas field Qiongdongnan basin

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Age-Period-Cohort Analysis on Long-Term Mortality Trend of Genitourinary Diseases—China,1987–2021

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China CDC weekly 2023年第51期5卷 1135-1139页

作者： Panliang Zhong Chen Chen Yunduo Liu Xinyue Wei Feipeng Cui shuai guo Yaohua Tian School of Population Medicine and Public Health Chinese Academy of Medical Sciences/Peking Union Medical CollegeBeijingChina Department of Aging and Health School of Population Medicine and Public HealthChinese Academy of Medical Sciences/Peking Union Medical CollegeBeijingChina APEC Health Science Academy(HeSAY) Peking University/Institute of Population ResearchPeking UniversityBeijingChina School of Public Health Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan CityHubei ProvinceChina Ministry of Education Key Laboratory of Environment and Health and State Key Laboratory of Environmental Health(Incubating)School of Public HealthTongji Medical CollegeHuazhong University of Science and TechnologyWuhan CityHubei ProvinceChina.

What is already known about this topic?There has been a lack of attention to genitourinary diseases for an extended period,resulting in limited research on the mortality trends of genitourinary diseases in *** is added by this report?This study examines the long-term trend of genitourinary diseases'mortality across Chinese individuals of all genders and in various urban and rural ***,it investigates the impact of age-period-cohort effects on this *** are the implications for public health practice?It is imperative to address genitourinary diseases,particularly among vulnerable populations such as rural older *** should prioritize these individuals by providing necessary policy interventions and healthcare support.

关键词： urinary mortality diseases

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