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Promoting the La solution in 2:14:1-type compound:resultant chemical deviation and microstructural nanoheterogeneity

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Journal of materials Science & Technology 2021年第3期62卷 195-202页

作者： Yongsheng Liu Jiaying Jin Tianyu ma Baixing Peng Xinhua Wang Mi Yan School of materials Science and Engineering State Key Laboratory of Silicon materialsKey Laboratory of Novel Materials for Information Technology of Zhejiang ProvinceZhejiang UniversityHangzhou310027China

rE_(2)Fe_(14)B-based(rE,rare earth)permanent magnets containing abundant and cheap La/Ce have attracted intense attention *** comparison with Ce that can fully replace nd in the 2:14:1 lattice,La substitution for nd has long been limited at a low *** we present that through doping La35 Ce65 alloy with the La/Ce ratio in natural mineral,stable 2:14:1 phase can be maintained at 1273 K within the entire substitution range of[(La_(35)Ce_(65))、(Pr_(20)nd_(80))_(1-x)]_(2.14)Fe_(14)B(0.6≤x≤1.0,at.%),as verified by composition analysis,microstructural characterization and magnetic ***,the promoted La solution in 2:14:1 phase induces two unique findings upon coexisting La-Ce-Pr-nd:i)Compared to Ce that fits well with the nominal concentration,La deviates noticeably from the nominal one;ii)nanoscale spinodal-decomposition-like phase separation is observed due to different solubilities of La-Ce-Pr-nd elements in 2:14:1 *** joint effects induce higher Curie temperature than estimation based on the rule of mixture,which delights the prospect of La_(35)Ce_(65)alloy in developing low-cost permanent materials.

关键词： La-Ce Permanent magnets nd-Fe-B Microstructure

Laboratory acoustic emission study for earthquake generation process

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Earthquake Science 2014年第6期27卷 627-646页

作者： Xinglin Lei Shengli ma Geological Survey of Japan National Institute of Advanced Industrial Science and Technology (AIST) State Key Laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration

Since the similarity in size distribution of earthquakes and acoustic emissions （AE） was found in the 1960s, many laboratory studies have been motivated by the need to provide tools for the prediction of mining failures and natural earthquakes. This paper aims, on the one hand, to draw an outline of laboratory AE studies in the last 50 years, which have addressed seismological problems. Topics include the power laws in which the similarity between AEs and earthquakes is involved and progress that has been made in AE technology and laboratory AE study. On the other hand, this study will highlight some key issues intensively discussed, especially in the last three decades, such as aspects related to the pre-failure damage evolution, fault nucleation and growth in brittle rocks and discuss factors governing these processes.

关键词： Acoustic emission (AE) Pre-failure damage rock fracture Earthquake Fault nucleation Process zone

notes for a History of Gas Geochemistry

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Journal of Earth Science 2022年第6期33卷 1614-1623页

作者： Guodong Zheng Giovanni martinelli Yanxin Wang Shun Li Xiangxian ma School of Environmental Studies China University of GeosciencesWuhan430078China northwest Institute of Eco-Environment and resources Chinese Academy of SciencesLanzhou730000China InGV national Institute of Geophysics and Volcanology Palermo90146Italy College of Information Engineering Shenyang Open UniversityShenyang110003China

During ancient times,human interest in naturally-occurring gases was religious,while it was scientific in the historical age and industrial in modern *** were also utilized for practical purposes and more than 3000 years before present day,Chinese populations made use of methane for salt extraction while in the 17th century it was observed that native Americans ignited methane *** development of human thinking on gases followed the fundamental steps that characterized the natural sciences during the 18th century scientific revolution that was based on significant improvements in analytical *** improvements are still ongoing while present-day scientific publications evidence the spread of the field of interest and more cooperation with geophysical sciences to solve common interest *** existence of proper meetings and dedicated scientific journals confirms that gas geochemistry has ended this pioneering phase to enter a more mature condition.

关键词： history of earth sciences gas geochemistry isotopic analysis carbon dioxide noble gases earthquakes hydrocarbons

Stage separation of recoverable liquid launch vehicle by using moving pulsating ball analogue for propellant sloshing

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Chinese Journal of Aeronautics 2024年第2期37卷 360-370页

作者： Yu LU Baozeng YUE Bailong HAO Bole ma Feng LIU Yuanyuan CHAnG School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Astronautical Systems Engineering Beijing 100076China

In the process of stage separation of recoverable liquid launch vehicles,because of the large amount of residual fuel in the storage tanks,the influence of liquid sloshing on separation safety must be *** calculation simplicity and operation practicability,the Moving Pulsating Ball Model(MPBM)of large amplitude liquid sloshing is introduced into the calculation of launch vehicle stage *** the dynamic equation of the model with the energy relationship during"breathing movement",the formula calculating the force of liquid on the rigid body is *** with the calculations of commercial CFD calculation software,the accuracy of MPBM model is ***,all the external forces and moments are applied to the rigid body of the stages,so that the translational and rotational dynamic equations of the stages are obtained *** to the relative position of the two stages,the geometric shape of the interstage section and the engine of the second stage,the minimum clearance in the separation process can be decided to guarantee that the separation process is safe.

关键词： Moving Pulsating Ball Model(MPBM) Dynamics of stage separation Large amplitude sloshing recoverable liquid launch vehicle Flight dynamics

Ash removal from inferior coal via ammonium fluoride roasting and simultaneous yield of white carbon black

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International Journal of Mining Science and Technology 2024年第2期34卷 261-279页

作者： Xuqin Duan Shuaiyu Lu Yuxiao Fu Jiazhe Zhang Tong Liu Jian ma School of Civil and resource Engineering University of Science&Technology BeijingBeijing 100083China State Key Laboratory for Efficient Mining of Metal Mines University of Science&Technology BeijingBeijing 100083China China Coal Processing and Utilizaiton Association Beijing 100013China

The quality upgrading and deashing of inferior coal by chemical method still faces great *** dangers of strong acid,strong alkali,waste water and exhaust gas as well as high cost limit its industrial *** paper systematically investigates the ash reduction and desilicification of two typical inferior coal utilizing ammonium fluoride roasting *** the optimal conditions,for fat coal and gas coal,the deashing rates are 69.02%and 54.13%,and the desilicification rates are 92.64%and 90.27%,*** molar dosage of ammonium fluoride remains consistent for both coals;however,the gas coal,characterized by a lower ash and silica content(less than half that of the fat coal),achieves optimum deashing effect at a reduced time and *** majority of silicon in coal transforms into gaseous ammonium fluorosilicate,subsequently preparing nanoscale amorphous silica with a purity of 99.90%through ammonia *** of the fluorine in deashed coal are assigned in inorganic minerals,suggesting the possibility of further fluorine and ash removal via *** research provides a green and facile route to deash inferior coal and produce nano-scale white carbon black simultaneously.

关键词： Inferior coal Deashing treatment Silicon recycling Ammonium fluoride roasting White carbon black

reduced Bone Mineral Density and Bone Metabolism in Aquaporin-1 Knockout Mice

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Chemical research in Chinese Universities 2007年第3期23卷 297-299页

作者： WU Qing-tian ma Qing-jie HE Cheng-yan WAnG cai-xia GAO Shi HOU Xia.ma.Tong-hui Membrane Channel research Laboratory Northeast Normal University Changchun 130024 P. R. China China-Japan Union Hospital Jilin University Changchun 130033 P. R. China School of Basic Medicine Jamasi University Jamasi 154002 P. R. China

An overt phenotype of aquaporin-1 knockout（AQP1 ko） mice is growth retardation, suggesting possible defects in bone development and metabolism. In the present study, we analyzed the bone mineral density（ BMD）, bone calcium and phosphorus contents, and bone metabolism in an AQP1 ko mouse model. The BMD of femurs in AQP1 ko mice was significantly lower than that of litter-matched wildtype mice as measured by dual energy X-ray absorptiometry. Consistently, the contents of bone total calcium and phosphorus were also significantly lower in AQP1 ko mice. The reduced BMD caused by AQP1 deficiency mainly affect male mice. Bone metabolic activity, as indicated by 99m^Tc-MDP absorption measurements, was remarkably reduced in AQP1 ko mice. These results provide the first evidence that AQP1 play an important role in bone structure and metabolism.

关键词： Aquaporin Gene knockout Bone mineral density Bone metabolism

Intraseasonal variability of the Kuroshio observed via mooring at 18°n

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Journal of Oceanology and Limnology 2024年第2期42卷 468-483页

作者： Xin YUAn Qingye WAnG Jie ma Shijian HU Dunxin HU Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China Laoshan Laboratory Qingdao 266237China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China

Insufficient observations near the origin of the Kuroshio have led to incomplete understanding of the intraseasonal variability(ISV)of the *** measurements of the Kuroshio velocity were performed with an array of three profiler moorings(122.7°E,123°E,and 123.3°E)along 18°n from January 2018 to February *** ISV of the Kuroshio at 18°n was investigated based on a combination of mooring observations and global high-resolution HYbrid Coordinate Ocean Model reanalysis *** estimated time-averaged transport in the upper 350 m across the observation transect was 6.5±2.6 Sv(1.0 Sv=10^(6)m^(3)/s).Two significant ISV peaks at 50-60 and~100 d were recognized in the power spectra of the meridional velocity and *** analysis indicated that the ISV at 50-60 d was caused by westward-propagating eddies at average propagation speed of~13 cm/s and wavelength of~635 *** ISV peak at~100 d was mainly caused by northward-propagating eddies generated in the north Equatorial Current *** investigation indicated that the ISV of the Kuroshio at 18°n is dominated by meridional transport,rather than by the zonal migration of the Kuroshio main *** findings provide a better understanding of the ISV of the Kuroshio east of Luzon Island.

关键词： intraseasonal variability(ISV) Kuroshio mooring observation eddy

Modulation of neuronal Activity and Saccades at Theta rhythm During Visual Search in non-human Primates

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neuroscience Bulletin 2022年第10期38卷 1183-1198页

作者： Jin Xie Ting Yan Jie Zhang Zhengyu ma Huihui Zhou The Brain Cognition and Brain Disease Institute Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research InstitutionsShenzhen518055China University of Chinese Academy of Sciences Beijing100049China The research Center for Artificial Intelligence Peng Cheng LaboratoryShenzhen518000China

Active exploratory behaviors have often been associated with theta oscillations in rodents,while theta oscillations during active exploration in non-human primates are still not well *** recorded neural activities in the frontal eye field(FEF)and V4 simultaneously when monkeys performed a free-gaze visual search *** were strongly phase-locked to theta oscillations of V4 and FEF local field potentials,and the phase-locking was dependent on saccade *** spiking probability of V4 and FEF units was significantly modulated by the theta phase in addition to the time-locked modulation associated with the evoked response.V4 and FEF units showed significantly stronger responses following saccades initiated at their preferred *** causality and ridge regression analysis showed modulatory effects of theta oscillations on saccade ***,our study suggests phase-locking of saccades to the theta modulation of neural activity in visual and oculomotor cortical areas,in addition to the theta phase locking caused by saccade-triggered responses.

关键词： Visual search Saccade Theta rhythm FEF V4 non-human primate

LiOH: A "double-edged" effect toward electrochemical oxidation of Li_(2)O_(2)

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Journal of Energy Chemistry 2021年第6期30卷 401-405,I0010页

作者： Qinghua Cui Lipo ma Peng Zhang Yuliang cao Jiawei Wang Laboratory of Advanced Spectro-electrochemistry and Lithium-ion Batteries Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022JilinChina Department of materials Science&Engineering Academy for Advanced Interdisciplinary StudiesShenzhen Key Laboratory of Solid State BatteriesGuangdong Provincial Key Laboratory of Energy Materials for Electric PowerSouthern University of Science and TechnologyShenzhen 518055GuangdongChina College of Chemistry and Molecular Sciences Engineering Research Center of Organosilicon Compounds&Materials of Ministry of EducationWuhan UniversityWuhan 430072HubeiChina Institute of materials Engineering Beijing Institute of Collaborative InnovationBeijing 100094China

The aprotic lithium-oxygen battery(Li-O_(2) battery) has attracted much attraction for the future advanced battery technologies due to its ultra-high theoretical energy density that can well meet the ever-growing ener... 详细信息

关键词： Lithium-oxygen batteries LiOH-doped Li_(2)O_(2) Li_(2)O_(2)oxidation Differential electrochemical mass spectrometer Isotope-labelling