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The role ofβ,γ,δ-substituent of dialkylphosphinic acids in HREE extraction and separation behaviors

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Journal of Rare Earths 2023年第11期41卷 1789-1795,I0005页

作者： Junlian Wang Wen Xu Jianguo Cui Guodong Xu Yufu Chen Peilong Wang Ziyong Chang School of Civil and Resource Engineering University of Science and Technology BeijingBeijing100083China State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou Research Institute of Rare EarthsBaotou014030China Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines Beijing100083China

Heavy rare earth element(HREE)separation has always been a great *** kind of dialkylphosphinic acids is recognized as the third generation of organophosphorous acid ***,detailed relationship betweenβ-substituent(especially when it changes from H to methyl,and further to ethyl)and their extraction behaviors and selectivity for HREEs have rarely been ***,there are also few reports on effect ofγ,δ-substituent on HREE extraction and *** this paper,we synthesized five and collected two dialkylphosphinic acids with differentβ,γ,δ-substituents(from H to ethyl).These extractants were divided into two groups to discuss their extraction behaviors and selectivity for HREEs:β-substituent group(P208,INET-1,P218,USTB-1 and P227)andγ,δ-substituent group(P218,P2132 and Cyanex 272).To evaluate and compare their extractabilities,P507 was used as a reference and Tm,Yb,Lu were extracted with 0.01 mol/L of these extractants from single Tm,Yb and Lu solutions(~4×10^(-4)mol/L)at different initial ***,pH_(0.5)(Tm),pH_(0.5)^(Yb)and pH_(0.5)^(Lu)values and their differences(ΔpH_(0.5)^(Tm-Yb),ΔpH_(0.5)^(Yb-Lu),ΔpH_(0.5)^(Tm-Lu))for each extractant were given to roughly evaluate their separation performance for Tm,Yb and *** further investigate the selectivity of these extractants for HREEs,Tb,Dy,Ho,Er,Tm,Yb and Lu were extracted from their mixed solution with initial pH of 4.00 at phase ratio A/O of 2:1,1:1 or 1:*** HREE separation performance is mainly discussed based on the adjacent HREE separation factors(β_(N+1/N))and their average value(β_(Tb-Lu)).

关键词： Heavy rare earth element Extraction Separation Dialkylphosphinic acid Substituent effect

Phase field modeling of grain stability of nanocrystalline alloys by explicitly incorporating mismatch strain

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Rare Metals 2024年第7期43卷 3370-3382页

作者： Min Zhou Hong-Hui Wu Yuan Wu Hui Wang Xiong-Jun Liu Sui-He Jiang Xiao-Bin Zhang Zhao-Ping Lu Beijing Advanced Innovation Center for Materials Genome Engineering State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083Cnina Institute for Carbon Neutrality University of Science and TechnologyBeijing 100083China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China

Ab st ra ct Nanocrystalline materials exhibit unique properties due to their extremely high grain boundary(GB) ***,this high-density characteristic induces grain coarsening at elevated temperatures,thereby limiting the widespread application of nanocrystalline *** experimental observations revealed that GB segregation and second-phase pinning effectively hinder GB migration,thereby improving the stability of nanocry stalline *** this study,a mouified phase-field model that integrates mismatch strain,solute segregation and precipitation was developed to evaluate the influence of lattice misfit on the thermal stability of nanocrystalline *** simulation results indicated that introducing a suitable mismatch strain can effectively enhance the microstructural stability of nanocrystalline *** synergizing precipitation with an appropriate lattice misfit,the formation of second-phase particles in the bulk grains can be suppressed,thereby facilitating solute segregation/precipitation at the *** concentrated solute segregation and precipitation at the GBs effectively hinders grain migration,thereby preventing grain *** findings provide a new perspective on the design and regulation of nanocrystalline alloys with enhanced thermal stability.

关键词： Phase field model Mismatch strain Second-phase precipitation Grain boundary segregation Nanocrystalline alloys

Non-physiological shear stress-induced blood damage in ventricular assist device

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Medicine in Novel Technology and Devices 2019年第3期3卷 9-15页

作者： Zengsheng Chen Anqiang Sun Hongyu Wang Yubo Fan Xiaoyan Deng Beijing Advanced Innovation Center for Biomedical Engineering Beihang UniversityBeijing100083China School of Biological Science and Medical Engineering Beihang UniversityBeijing100083China

Ventricular assist devices(VADs)have been used for treating the end-stage heart failure(HF)patients in the past few decades,which had improved survival *** parallel,clinical applications of VADs are accompanied with endangered complications,such as thrombosis,bleeding and infection,which hamper the patient *** shear stress(NPSS)is inevitably created during VAD *** HF patients implanted with VADs,this high level NPSS can induce damage on blood components including blood cells(red blood cells,platelets,leukocytes et al.)and protein(von Willebrand Factor(VWF)).The damage of these blood cells and proteins may lead to the dysfunction of coagulation and immune systems,contributing to complications in VAD *** understand how VADs-created NPSS induces blood damage,and find the link between NPSS-induced blood damage and VAD related complications would potentially help to guide the VAD optimization and to find the effect way for treating VAD associated *** we provide a review to investigate what is currently known about NPSS-induced blood damage within VADs and how the NPSS-induced blood damage links to complications(thrombosis,bleeding and infection)in VAD patients.

关键词： Ventricular assist device Non-physiological shear stress Blood damage Thrombosis Bleeding

The anatomical structure of woody plants in arid habitats is closely related to nonstructural carbohydrates storage

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Forest Ecosystems 2022年第6期9卷 764-774页

作者： Zedong Li Xinxiao Yu Guodong Jia Key Laboratory of State Forestry and Grassland Administration on Soil and Water Conservation Beijing Forestry UniversityBeijing100083China

Background:The high temperatures and drought conditions associated with global climate change have led to the widespread death of trees and forests,which has generated research interest in the impact of non-structural carbohydrates(NSC)reserves on woody plant survival in changing *** anatomical characteristics of plants can affect the scale and variability of NSC reserves,and linking the anatomical characteristics of trees to NSC concentration can help answer questions about the potential role of NSC in the repair of xylem embolism during ***:The anatomical characteristics,NSC concentrations and gas exchange parameters were determined in 16 common afforestation tree species in typical arid limestone habitats in rocky mountain *** found that the anatomical structures varied greatly among the tree species studied,and a branch xylem hydraulic efficiency-safety tradeoff was not *** concentration was significantly and positively correlated with variables including mean vessel diameter(MVD),maximum vessel diameter(XVD),potential hydraulic conductivity(Kp),vessel wall thickness(VWT),ratio of palisade tissue thickness to sponge tissue thickness(PT/ST),net photosynthetic rate(Pn),water use efficiency(WUE)and axial parenchyma cell area,and negatively with sponge tissue thickness(ST)and lower epidermis thickness(LET)of *** the four latent variables,mechanical strength was inversely related to NSC concentration,whilst hydraulic efficiency,leaf carbon fixation,and the embolism repair and storage capacity all had a positive ***:Our study revealed that tree species with larger vessel diameters,thicker vessel walls,more abundant axial parenchyma,and higher PT/ST have higher NSC storage in arid habitats in northern *** xylem anatomical characteristics and leaf anatomical characteristics among different tree species lead to differentiated water transport and photosynthetic processes,thereby regulating the NSC

关键词： Drought Embolism Leaf anatomy NSC concentration Xylem

Heterogeneity in predisposition of hepatic cells to be induced into pancreatic endocrine cells by PDX-1

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World Journal of Gastroenterology 2005年第15期11卷 2277-2282页

作者： ShunLu Wei-PingWang Xiao-FeiWang Zong-MeiZheng PingChen Kang-TaoMa Chun-YanZhou DepartmentofBiochemistryandMolecularBiology SchoolofBasicMedicalSciencesPekingUniversityBeijing100083China PekingUniversityStemCellResearchCenter Beijing100083China

AIM: The role of Pancreatic and Duodenal Homeobox-1(PDX-1) as a major regulator of pancreatic development determines the function and phenotype of β cell. In this study, potential plasticity of liver cells into pancreatic endocrine cells induced by PDX-1 was ***: Human hepatoma cell line HepG2 was stably transfected with mammalian expression plasmid pcDNA3-PDX encoding human PDX-1 gene. Ectopic expression of PDX-1 and insulin were detected by RT-PCR,Western blot and/or immunostaining. PDX-1+ HepG2 cells were transplanted under renal capsule of STZ-induced diabetic nude mice (n = 16) to examine the inducing effect in ***: Exogenous PDX-1 transgene was proved to express effectively in HepG2 cell at both mRNA and protein levels. The expression of endogenous insulin and some βcell-specific differentiation markers and transcription factors were not induced in PDX-1+ HepG2 cells. When transplanted under renal capsule of STZ-induced diabetic nude mice, PDX-1+ HepG2 cells did not generate insulinproducing cells. These data indicated that stable transfected PDX-1 could not convert hepatoma cell line HepG2 to pancreatic cells in vitro or in vivo. Mature hepatocytes might need much more complicated or rigorous conditions to be shifted to insulin-producing ***: The expression of exogenous PDX-1 is not sufficient to induce relatively mature hepatocytes differentiating into insulin-producing cells.

关键词： PDX-1 HepG2, Insulin Transgene Diabetes

Indeterminacy Causal Inductive Automatic Reasoning Mechanism Based on Fuzzy State Description

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Journal of Systems Engineering and Electronics 2002年第2期13卷 64-70页

作者： Yang Bingru & Tang JingDept. of Computer Science and Engineering, University of Science and Technology, Beijing 100083, P.R.China(Received May 23, 2001) Dept. of Computer Science and Engineering University of Science and Technology Beijing 100083 P. R. China

A framework of knowledge representation of fuzzy language field and fuzzy language value structure is shown. Then the generalized cell automation that can synthetically process fuzzy indeterminacy and random indeterminacy and generalized inductive logic causal model are put forward. On this basis, the logic indeterminacy causal inductive automatic reasoning mechanism which is based on fuzzy state description is presented. At the end of this paper its application in the development of intelligent controller is discussed.

关键词： Control systems Fuzzy sets

Investigation on environment monitoring system for a combination of hydroponics and aquaculture in greenhouse

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Information Processing in Agriculture 2022年第1期9卷 123-134页

作者： Shanhong Zhang Yu Guo Shuai Li Zhixin Ke Huajian Zhao Jinqi Yang Yang Wang Daoliang Li Liang Wang Wenhua Yang Zhili Zhang National Innovation Center for Digital Fishery China Agricultural UniversityBeijing 100083China College of Information and Electrical Engineering China Agricultural UniversityBeijing 100083China Beijing Zhong Nong Tianlu Micro-nano Bubble Water Science and Technology Co. LtdChina

This work develops a distributed environmental monitoring system for the combination of hydroponics and aquaculture based on the internet of things technology,which mainly includes the information perception layer,the information transmission layer and the sys-tem *** system has employed multiple sensors terminal to real-time acqui-sition,including air and water temperatures,dissolved oxygen *** protocol is suitable for sending small data and the 4G was employed to collect data and send to the cloud *** is used to develop background applications,to access cloud platforms and local data *** on the collection and processing of environmental data and cloud service platform,the mobile application program client and remote login desktop have been *** has been implemented and tested in Tongzhou,Beijing for 3 months in *** results showed the proposed monitoring system stability for overall operation and accuracy data transmission,which can support the actual hydroponics and aquacul-ture production *** analysis of monitoring data collected from the devel-oped monitoring system,indoor air and water temperature have the obvious correlation with atmospheric pressure(0.7 and 0.9)and outdoor temperature(1.0 and 0.9),respectively.

关键词： Monitoring system Hydroponics Aquaculture Greenhouse Internet of things Greenhouse environment

Organic-Inorganic Interaction Recorded by Polycyclic Aromatic Steranes in Continental Epithermal Ore Deposits

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Acta Geologica Sinica(English Edition) 2023年第1期97卷 327-336页

作者： XU Huiyuan LIU Quanyou JIN Zhijun ZHU Dongya MENG Qingqiang LI Pengpeng ZHU Biqing State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development Beijing 100083China Petroleum Exploration&Production Research Institute SINOPECBeijing 100083China Institute of Energy School of Earth cand Space SciencesPeking UniversityBeijing 100871China

Continental epithermal ore deposits are commonly associated with sedimentary organic matter,oils or solid *** organics embedded in mineral deposits can convey valuable information of the ore ***,the extent to which the formation of ore minerals was recorded by organic compounds remains largely unknown,as also is how metal-rich ores interfere with the molecular proxies in the temperature regime envisaged for hydrothermal *** molecular compositional changes of various polycyclic aromatic steranes and polycyclic aromatic hydrocarbons and compounds derived from the Jinding Pb/Zn deposit,SW China provide new *** regular steranes are present as *** transformation from polycyclic aromatic steranes to unsubstituted polycyclic aromatic hydrocarbons is observed to show an increased trend with increasing hydrothermal alteration levels;this is consistent with the transformation from unsubstituted polycyclic aromatic hydrocarbons to heterocyclic ***(aromatization)of polycyclic biological compounds and hydrodecyclization(dearomatization)of polycyclic aromatic compounds are two important reaction pathways in hydrothermal systems with moderate *** detailed investigation of organicinorganic interactions of two groups of polycyclic compounds with metal-rich ores provides insights into the questions on how and to what extent the formation of Pb/Zn deposits can be recorded by *** work will improve our understanding of carbon reduction,oxidation or condensation in the deep Earth and the carbon exchange between the Earth's crust and mantle,and may shed light on the processes for ultra-deep hydrocarbon exploration.

关键词： petroleum resources organic-inorganic interaction biomarker polycyclic compounds hydrothermal environment

Strain Distributions in Non-Polar a-Plane In_(x)Ga_(1−x)N Epitaxial Layers on r-Plane Sapphire Extracted from X-Ray Diffraction

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Chinese Physics Letters 2013年第9期30卷 169-172页

作者： ZHAO Gui-Juan YANG Shao-Yan LIU Gui-Peng LIU Chang-Bo SANG Ling GU Cheng-Yan LIU Xiang-Lin WEI Hong-Yuan ZHU Qin-Sheng WANG Zhan-Guo Key Laboratory of Semiconductor Materials Science Institute of SemiconductorsChinese Academy of SciencesP.O.Box 912Beijing 100083 Beijing Key Laboratory of Low Dimensional Semiconductor Materials and Devices Institute of SemiconductorsChinese Academy of SciencesP.O.Box 912Beijing 100083

By using x-ray diffraction analysis,we investigate the major structural parameters such as strain state and crystal quality of non-polar a-plane In_(x)𝑦Ga_(1−x)𝑦N thin films grown on r-sapphire substrates by metalorganic chemical vapour *** results of the inplane grazing incidence diffraction technique are analyzed and compared with a complementary out-of-plane high resolution x-ray diffraction *** the indium composition is low,the a-plane In_(x)𝑦Ga_(1−x)𝑦N layer is tensile strain in the growth direction(𝑏a-axis)and compressive strain in the two in-plane directions(𝑛a-axis and𝑑a-axis).The strain status becomes contrary when the indium composition is *** stress in the𝑛a-axis direction𝜏σyy is larger than that in the a-axis directionσ***,strain in the two in-plane directions decrease and the crystal quality becomes better with the growing of the In_(x)Ga_(1−z)N film.

关键词： technique deposition. plane