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Integrated purification of gadolinium and preparation of Gd2O_(3) nanoparticles by DC arc plasma

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Journal of Rare Earths 2021年第12期39卷 1574-1578,I0005页

作者： Zhenggang Tang Minjie Hou Xin He Kai ye Da Zhang Zhipeng Xie Yongnian Dai Feng Liang The National Engineering Laboratory for Vacuum Metallurgy Kunming University of Science and TechnologyKunming 650093China Key Laboratory for Nonferrous Vacuum Metallurgy of Yunnan Province Kunming University of Science and TechnologyKunming 650201China Institute of Physical Education Yunnan Agriculture University State Key Laboratory of Complex Nonferrous Metal Resources Clear Utilization Kunming University of Science and TechnologyKunming 650093.China

The rare-earth metal Gd plays an important role in the energy,information,and national defence fields due to its special optical,electrical,magnetic,and catalytic *** this study,Gd was purified by direct current(DC)arc plasma,and Gd2O_(3) nanoparticles were prepared via an integration method using purified *** effects of arc current,melting time,gas pressure,and atmosphere on the purification of Gd by DC arc plasma were *** an increase in the arc current and melting time,the rate of removal of impurities from Gd ***,Gd melting was conducted by H_(2)-Ar arc plasma,which improves the impurity removal rate by increasing the H_(2) *** thermal conductivity and chemical activity of the activated H atoms generated by the dissociation of H_(2) are the main reasons for the significant improvement in the impurity removal *** mechanism of Gd purification was analysed based on the above-mentioned experimental *** as-synthesised Gd2 O_(3) nanoparticles have a uniform spherical structure(average diameter of 32.7 nm),appropriate dispersibility,and high *** study provides a new strategy for the integrated purification of metals and preparation of metal/metal-based nanomaterials by DC arc plasma.

关键词： Gd DC arc plasma Purification Preparation Nanomaterial Integration

Distribution characteristics of wave energy in the Zhe-Min coastal area

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Acta Oceanologica Sinica 2022年第5期41卷 163-172页

作者： Qin ye Zhongliang Yang Min Bao Weiyong Shi Hongyuan Shi Zaijin You Wenyan Zhang Second Institute of Oceanography Ministry of Natural ResourcesHangzhou310012China State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou310012China Ludong University Yantai264025China Dalian Maritime University Dalian116026China Institute of Coastal System Helmholtz-Zentrum HereonGeesthacht21502Germany

A 10-year(2003–2012)hindcast was conducted to study the wave field in the Zhe-Min coastal area(Key Area OE-W2)located off Zhejiang and Fujian provinces of *** by the wind field from a weather research and forecasting model(WRF),high-resolution wave modelling using the SWAN was carried out in the study *** simulated wave fields show a good agreement with *** the simulation results,we conducted statistical analysis of wave power density in terms of spatial distribution and temporal *** effective duration of wave energy in the sea area was discussed,and the stability of wave energy was evaluated using the coefficient of variation of wave power *** indicate that the wave energy resource in the study area was about 4.11×10^(6) *** distribution of wave energy tends to increase from the north(off Zhejiang coast)to the south(off Fujian coast),and from near-shore area to the open *** sea areas with wave power density greater than 2 kW/m are mostly distributed seaward of the 10-m isobath,and the contours of the wave power density are almost parallel to the *** sea areas around the islands that are far from the mainland are rich in wave energy,usually more than 6 kW/m,and therefore are of obvious advantages in planning wave energy development and *** effective duration of wave energy in the offshore area shows an increasing trend from north(off Zhejiang coast)to south(off Fujian coast),with values of∼3500 h in the north and∼4450 h in the *** coefficient of variation of wave energy in this region is mostly in the range of 1.5–3.0,and gradually decreases from the north to the south,suggesting that the wave energy in the south is more stable than that in the north.

关键词： SWAN model wave energy wave power density effective duration Zhe-Min coastal area

Progress in Research on Materials Under Microgravity in China

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空间科学学报 2004年第Z1期24卷 138-149页

作者： CHEN Nuofu CHEN Wanchun LUO Xinghong ye Yude Key Laboratory of Semiconductor Materials Sciences Institute of Semiconductors The Chinese Academy of Sciences Beijing 100083 China National Laboratory of Microgravity Institute of Mechanics The Chinese Academy of Sciences Beijing 100080 China Institute of Physics The Chinese Academy of Sciences Beijing 100080 China National Laboratory of Microgravity Institute of Mechanics The Chinese Academy of Sciences Beijing 100080 China Institute of Metal Research The Chinese Academy of Sciences Shenyang 110016 China Key Laboratory of Semiconductor Materials Sciences Institute of Semiconductors The Chinese Academy of Sciences Beijing 100083 China

Research on materials under microgravity in China began in the 1980s, sparked by Prof. Lanying Lin (academician of CAS), Prof. Xiji Wang (academician of CAS), Prof. Guirong Min (academician of CAS), and Prof. Huabao Lin (academician of CAS), and others. The first semiconductor crystal, first optical crystal, and first alloys were grown in space on board a recoverable satellite in 1987. Since then, microgravity materials science became a new scientific branch in *** and technical activities on space crystal growth and solidification are carried out through two major programs: ground-based studies and orbital experiments. The main results obtained during 2001-2003 are reported below.

关键词： Microgravity, Semiconductor, Metal, Crystal

Ultra-lightweight ceramic scaffolds with simultaneous improvement of pore interconnectivity and mechanical strength

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Journal of Materials Science & Technology 2023年第6期137卷 247-258页

作者： ye Dong Annan Chen Ting Yang Shuai Gao Shuning Liu Hongyi Jiang Yusheng Shi Chenglong Hu School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China Engineering Research Center of Ceramic Materials for Additive Manufacturing Ministry of EducationWuhan 430074China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

The high porosity and interconnectivity of scaffolds are critical for nutrient transmission in bone tis-sue engineering but usually lead to poor mechanical ***,a novel method that combines acid etching(AE)with selective laser sintering(SLS)and reaction bonding(RB)of Al particles is pro-posed to realize highly improved porosity,interconnectivity,mechanical strength,and in vitro bioactivity in 3D Al_(2)O_(3) *** controlling the oxidation and etching behaviors of Al particles,a tunable hol-low spherical feature can be obtained,which brings about the distinction in compressive response and fracture *** prevention of microcrack propagation on the in situ formed hollow spheres results in unique near elastic buckling rather than traditional brittle fracture,allowing an unparalleled compressive strength of 3.72±0.17 MPa at a high porosity of 87.7%±0.4%and pore interconnectivity of 94.7%±0.4%.Furthermore,scaffolds with an optimized pore structure and superhydrophilic surface show excellent cell proliferation and adhesion *** findings offer a promising strategy for the coexistence of out-standing mechanical and biological properties,with great potential for tissue engineering applications.

关键词： Ceramic scaffolds Selective laser sintering Acid etching Hollow spherical feature Mechanical strength In vitro bioactivity

Advanced heterostructure of Pd nanosheets@Pt nanoparticles boosts methanol electrooxidation

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Journal of Energy Chemistry 2023年第10期85卷 430-438,I0012页

作者： Jie Li Cheng Wang Yuefan Zhang Shinichi Hata Kewang Zhang Changqing ye Yukihide Shiraishi Yukou Du College of Chemistry Chemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123JiangsuChina Jiangsu Key Laboratory for Environment Functional Materials School of Materials Science and EngineeringSuzhou University of Science and TechnologySuzhou 215009JiangsuChina Department of Applied Chemistry Faculty of EngineeringSanyo-Onoda City UniversitySanyo-OnodaYamaguchi 756-0884Japan School of Optical and Electronic Information Suzhou City UniversitySuzhou 215104JiangsuChina

Heterostructures have emerged as elaborate structures to improve catalytic activity owing to their combined surface and distinct inverse ***,fabricating advanced nanocatalysts with facetdependent interface remains an unexploited and promising ***,we render the controlled growth of Pt nanoparticles(NPs)on Pd nanosheets(NSs)by regulating the reduction kinetics of Pt^(2+)with ***,the fast reduction kinetic makes the Pt NPs uniformly deposited on the Pd NSs(U-Pd@Pt HS),while the slow reduction kinetic leads to the preferential growth of Pt NPs on the edge of the Pd NSs(E-Pd@Pt HS).Density functional theory calculations demonstrate that Pd(111)-Pt interface in U-Pd@Pt HS induces the electron-deficient status of Pd substrates,triggering the d-band center downshift and amplifying the Pd-Pt intermetallic *** synergy between the electronic effect and interfacial effect facilitates the removal of poisonous intermediates on U-Pd@Pt *** virtue of the Pd NSs@Pt NPs interface,the heterostructure achieves exceptional methanol oxidation reaction activity as well as improved *** study innovatively proposes heterostructure engineering with facetdependent interfacial modulation,offering instructive guidelines for the rational design of versatile heterocatalysts.

关键词： Heterostructure engineering Facet-dependent interfacial modulation Methanol oxidation reaction

Variation Characteristics of Hydrothermal Resources Effectiveness Under the Background of Climate Change in Southern Rice Production Area of China

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Journal of Integrative Agriculture 2013年第12期12卷 2260-2279页

作者： ye Qing YANG Xiao-guang DAI Shu-wei LI Yong GUO Jian-ping College of Resources and Environmental Science China Agricultural University Forestry Institute Jiangxi Agricultural University School of Natural Resources University of Nebraska-Lincoln Guizhou Key Laboratory of Mountainous Climate and Resources Chinese Academy of Meteorological Sciences

The spatiotemporal characteristics of hydrothermal resources in southern rice production area of China have changed under the background of climate change,and this change would affect the effectiveness of hydrothermal resources during local rice growing *** to the cropping system subdivision in southern rice production area of China during 1980s,this study used climate data from 254 meteorological stations and phonological data from 168 agricultural observation stations in the south of China,and adopted 6 international evaluation indices about the effectiveness of hydrothermal resources to analyze the temporal and spatial characteristics of hydrothermal resources during the growing period of single cropping rice system and double cropping rice system for 16 planting zones in the whole study *** results showed that：in southern rice production area of China,the effectiveness of thermal resources of single cropping rice area（SCRA） was less than that of double cropping rice area（DCRA）,whereas the effectiveness of thermal resources of both SARA and DCRA showed a decreasing *** index value of effective precipitation satisfaction of SCRA was higher than that of DCRA,nevertheless the index value of effective precipitation satisfaction of both SCRA and DCRA showed a decreasing *** was a significant linear relationship between effective thermal resource and water demand,likely water demand increased by 18 mm with every 100°C d increase of effective *** precipitation satisfaction index（EPSI） showed a negative correlation with effective heat,yet showed a positive correlation with effective *** reduced by 1% when effective heat resource increased by 125°C *** study could provide insights for policy makers,land managers or farmers to improve water and heat resource uses and rationally arrange rice production activities under global climate change condition.

关键词： climate change rice production area effectiveness of hydrothermal resources spatiotemporal characteristics

Prognostic effect of excessive chemotherapy cycles for stage Ⅱ and Ⅲ gastric cancer patients after D2 + gastrectomy

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World Journal of Gastrointestinal Surgery 2023年第1期15卷 32-48页

作者： Yi-Fan Li Wen-Bing Zhang Yu-ye Gao Department of General Surgery Shanxi Province Cancer HospitalTaiyuan 030013Shanxi ProvinceChina Endoscopy Center Shanxi Province Cancer HospitalTaiyuan 030013Shanxi ProvinceChina Department of Gastrointestinal Surgery Peking University Cancer Hospital and InstituteBeijing 00010China

BACKGROUND According to relevant investigation and analysis,there are few research studies on the effect of excessive chemotherapy cycles after D2 gastrectomy on the survival of patients with gastric *** To determine whether excessive chemotherapy cycles provide extra survival benefits,reduce recurrence rate,and improve survival rate in patients with stage Ⅱ or Ⅲ gastric *** We analyzed and summarized 412 patients with stage Ⅱ gastric cancer and 902 patients with stage Ⅲ gastric cancer who received D2 gastrectomy plus adjuvant chemotherapy or neoadjuvant *** and comparison at a ratio of 1:1 is aimed at reducing realistic baseline differences(n=97 in each group of stage Ⅱ,n=242 in each group of stage Ⅲ).Progression-free survival,overall survival and recurrence were the main outcome *** When the propensity score was matched,the baseline features of stage Ⅱ and Ⅲ gastric cancer patients were similar between the two *** a series of investigations,Kaplan-Meier found that the progression-free survival and overall survival of stage Ⅱ and Ⅲ gastric cancer patients were consistent between the two *** local metastasis rate(P=0.002),total recurrence rate(P<0.001)and distant metastasis rate(P=0.001)in the≥9 cycle group of stage Ⅲ gastric cancer were statistically lower than those in the<9 cycle *** interaction analysis by Cox proportional hazard regression model showed that intestinal type,proximal gastrectomy,and≥6 cm maximum diameter of tumor had a higher risk of total mortality in the<9 cycles *** Overall,≥9 chemotherapy cycles is not recommended for patients with stage Ⅱ and stage Ⅲ gastric cancer because it has an insignificant role in the prognosis of gastric ***,for patients with stage Ⅲ gastric cancer,≥9 cycles of chemotherapy was shown to significantly decrease recurrence.

关键词： Gastric cancer Propensity score matching Chemotherapy cycles Overall survival Progressionfree survival Recurrence

Parity-time symmetric acoustic system constructed by piezoelectric composite plates with active external circuits

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Chinese Physics B 2022年第6期31卷 91-98页

作者： Yang Zhou Zhang-Zhao Yang Yao-Yin Peng Xin-ye Zou Key Laboratory of Modern Acoustics MOEInstitute of AcousticsDepartment of PhysicsCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China State Key Laboratory of Acoustics Chinese Academy of SciencesBeijing 100190China

Researches on parity-time(PT)symmetry in acoustic field can provide an efficient platform for controlling the travelling acoustic waves with balanced loss and ***,we report a feasible design of PT-symmetric system constructed by piezoelectric composite plates with two different active external *** judiciously adjusting the resistances and inductances in the external circuits,we obtain the exceptional point due to the spontaneous breaking of PT symmetry at the desired frequencies and can observe the unidirectional ***,the system can be at PT exact phase or broken phase at the same frequency in the same structure by merely adjusting the external circuits,which represents the active control that makes the acoustic manipulation more *** study may provide a feasible way for manipulating acoustic waves and inspire the application of piezoelectric composite materials in acoustic structures.

关键词： parity-time symmetry acoustic gain material piezoelectric composite plate exceptional point

Transport of phosphorus in runoff and sediment with surface runoff from bare purple soil during indoor simulated rainfall

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Journal of Mountain Science 2022年第8期19卷 2333-2345页

作者： MA Xiao YANG Jie ZHOU Xiang-jun WU Hong-tao XIONG Qiao LI ye College of Urban and Environmental Sciences Hubei Normal UniversityHuangshi 435002China Hubei Key Laboratory of Pollutant Analysis&Reuse Technology Hubei Key Research Institute of Humanities&Social ScienceHuangshi 435002China School of Resource and Environmental Engineering Wuhan University of TechnologyWuhan 430070China

Phosphorus(P)in surface runoff from purple soil is a critical element of agricultural nonpoint source pollution,leading to eutrophication of surface waters in the Three Gorges Reservoir Area(TGRA)of *** work aimed to understand the processes and mechanisms of P losses from bare purple *** on an indoor rainfall simulation experiment,we focused on the processes of surface runoff and P losses via different hydrological *** treatments included three simulated rainfall intensities,four slope gradients,and three fertilizer treatments.P loss from sediment was the main pathway in the purple soil,and bioavailable P was mainly transferred in dissolved P(DP)of runoff *** P loss loads tend to grow with the increase of the slope until 25°for the maximum load of runoff water and 20°for the maximum load of *** of DP in the surface runoff after fertilizer application can exceed the estimates of those required for accelerated *** P control might be an essential way for reducing P loss in purple soil for the local government and farmers of TGRA.

关键词： Surface runoff Sediment yield Phosphorus loss Purple soil Simulated rainfall