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Effect of Soda Ash on Properties of Mold Flux and Mineralogical Structures of Flux Film

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Journal of Iron and Steel Research International 2016年第3期23卷 197-202页

作者： xiu-li han Yi-fei ZhanG Lei liU li-na liU han ZhanG College of Mining Engineering North China University of Science and Technology

During continuous casting,properties of mold flux and mineralogical structures of flux film play important roles in controlling steel *** effect of soda ash on the physical properties and crystallization characteristics of mold flux was investigated using process mineralogy,including polarizing microscopy,X-ray diffraction,and electron microprobe,*** flux was mainly prepared using cement clinker and industrial mineral materials under laboratory conditions,and the mineralogical structures of the flux film were systematically identified and quantitatively *** results showed that,by increasing the soda ash content from 10mass% to 18mass%,the crystallization temperature,critical cooling rate and crystallization ratio of the flux film decreased,but the crystallization ratio still reached 75% after adding soda ash,and the mineral compositions and microstructures of the flux film changed *** the soda ash content exceeded 14mass%,the critical cooling rate and the crystallization ratio decreased slightly,whereas the mineral content of the flux film changed evidently,with a large amount of cuspidine precipitation and a significant decrease in the wollastonite content until it reached zero,which resulted in deterioration of the lubrication of the flux film.

关键词： soda ash mold flux flux film crystallization property mineralogical structure

数据驱动教育数字化转型的信任机制——教育大数据全生命周期隐私增强模型的构建与典型应用场景分析

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现代教育技术 2024年第3期34卷 28-38页

作者：王涛张玉平李秀晗刘清堂张思华中师范大学人工智能教育学部湖北武汉430079

教育大数据正在成为驱动国家教育数字化转型战略行动的核心资源,带来了巨大的教育价值,但教育大数据的采集和分析产生了隐私侵害风险、信任危机等严峻问题,阻碍了数据的共享、开发和利用。如何增强教育大数据在开放共享、共建共用中的... 详细信息

教育大数据正在成为驱动国家教育数字化转型战略行动的核心资源,带来了巨大的教育价值,但教育大数据的采集和分析产生了隐私侵害风险、信任危机等严峻问题,阻碍了数据的共享、开发和利用。如何增强教育大数据在开放共享、共建共用中的隐私保护和信任关系,成为制约数据驱动教育数字化转型的关键难题。对此,文章首先采用文献分析法,剖析了教育大数据隐私保护的研究现状与关键问题。随后,文章从应用场景角度设计了教育大数据全生命周期隐私增强框架,并基于此框架从技术实现角度构建了满足不同实体、不同阶段隐私需求的教育大数据全生命周期隐私增强模型及其应用流程。最后,文章介绍了该模型的典型应用场景,涉及学分与资质认证、教育协同与治理、可信评教、个性化学习服务等多个方面。文章的研究能够厘清教育大数据开放共享时的隐私保护关键问题和技术思路,可为实现教育数据要素化全生命周期的隐私保护、建立健全数据驱动教育数字化转型的信任机制提供参考。

关键词：教育大数据隐私增强全生命周期开放共享

Cytotoxic Diarylheptanoids from Pericarps of Juglans Cathayensis Dode

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Chemical Research in Chinese Universities 2008年第4期24卷 427-429页

作者： li Yi-xiu RUAN han-li ZHOU Xue-feng ZhanG Yong-hui PI Hui-fang WU Ji-zhou Faculty of Pharmaceutical Sciences Tongji Medical College of Huazhong University of Science and Technology Wuhan 430030 P R. China

A novel diarylheptanoid, named Jugcathanin（1）, along with two known diarylheptanoids（2,3）, were isolated from the fresh pericarps ofduglans Cathayensis Dode. A known triterpene（4） and a known aphthaoquinone（5） were also isolated from the plant. Their structures were elucidated on the basis of spectroscopic studies. All the compounds exhibited moderate cytotoxicities against human Hela, HepG2, and HL-60 cell lines.

关键词： duglans Cathayensis Dode Jugcathanin Antitumor activity

A homopolymolybdate-supported plate-like 2D cobalt network constructed from a new pyrazole-amide-pyridyl ligand: highly electrochemical activity in both capacitive performance and the detection of Cr(Ⅵ)

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Tungsten 2024年第2期6卷 422-427页

作者： xiu-li Wang Yong-Zhen Chen Zhi-han Chang Yu-Chun lin Jing-Yi Ma College of Chemistry and Materials Engineering Bohai UniversityJinzhou 121013China Professional Technology Innovation Center of liaoning Province for Conversion Materials of Solar Cell Jinzhou 121013China

By employing a new semi-rigid pyrazole-amide-derived bis(pyridyl)ligand[N,N'-bis(4-picolylamine)-1-hydropyrazole(4-dpap)],a new homopolymolybdate-based two-dimensional(2D)plate-like complex[Co(4-dpap)(H_(2)O)(β-Mo_(8)O_(2)6)1/2](1)has been prepared under solvothermal condition and structurally ***β-Mo_(8)anions are fi xed between the 2D metal–organic networks[Co(4-dpap)(H_(2)O)]n 2n+via hydrogen-bonding *** 1 possesses satisfactory specifi c capacitance of 1512.4 F·g^(−1)(current density:1 A·g^(−1))and good cycling stability(90.8%after 1000 cycles).Moreover,1 represents a promising amperometric sensor for measurement of Cr(Ⅵ)with low detection limit(0.042μmol·L^(−1))and high *** insertion ofβ-Mo_(8)anions between the unique 2D metal−organic networks improves the active area of polyoxometalates,which further promotes electrochemical performance.

关键词： Homopolymolybdate Metal–organic network Pyrazole-amide-derived bis(pyridyl)ligand Supercapacitor Electrochemical sensor

Rapid analysis of metal ions and organic compounds in strong acidic solutions by nano-ESI mass spectrometry

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Chinese Chemical Letters 2024年第2期35卷 516-520页

作者： Jiaquan Xu Ting li Zhendong Yu lili Song xiu-xiu Xu Hui li Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation East China University of TechnologyNanchang 330013China Department of Rehabilitation Medicine The First Affiliated Hospital of Nanchang UniversityNanchang 330006China

Rapid analysis of metal ions and organic compounds in strong acidic solutions is of sustainable interest in multiple ***,complicated and time-consuming pretreatments are always required for MS analysis of the compounds in strong acidic ***,it will result in a weak signal and cause serious damage to the mass ***,a simple method inherited from nano-ESI MS was developed for rapid analysis of strong acidic ***(nL)strong acidic solution was first loaded in the nano-ESI emitter,followed by evaporation to remove the H+and leave the analytes on the wall of the nano-ESI *** evaporation process can be completed within 1 min because of the extremely tiny volume(≤1 nL)of the loaded ***,the dried analytes on the wall of the nano-ESI emitter were redissolved by loading a new solvent,followed by nano-ESI MS *** using this method,metal ions and organic compounds in the strong acidic solution can be detected with low sample consumption(1 nL),high speed(limit of detection=0.2µg/L),and high accuracy(>90%).Proof-of-concept applications of the present method have been successfully achieved for the analysis of gastric juice(pH of the sample=1),monitoring reaction catalyzed by strong acid(pH of the system=0),and micro-area analysis of ores(pH of the extraction solvent=0),showing great application potential in multiple fields.

关键词： Strong acidic solutions Nano-ESI MS Rapid analysis Reaction monitoring Micro-area analysis Gastric juice analysis

ATP6AP2,a regulator of LRP6/β-catenin protein trafficking,promotes Wnt/β-catenin signaling and bone formation in a cell type dependent manner

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Bone Research 2024年第2期12卷 453-468页

作者： Lei Xiong Hao-han Guo Jin-xiu Pan Xiao Ren Daehoon Lee li Chen lin Mei Wen-Cheng Xiong Department of Neurosciences School of MedicineCase Western Reserve UniversityClevelandOH 44106USA Louis Stoke VA Medical Center ClevelandOH 44106USA

Wnt/β-catenin signaling is critical for various cellular processes in multiple cell types,including osteoblast(OB)differentiation and *** how Wnt/β-catenin signaling is regulated in OBs remain ***6AP2,an accessory subunit of V-ATPase,plays important roles in multiple cell types/organs and multiple signaling ***,little is known whether and how ATP6AP2 in OBs regulates Wnt/β-catenin signaling and bone *** we provide evidence for ATP6AP2 in the OB-lineage cells to promote OB-mediated bone formation and bone homeostasis selectively in the trabecular bone *** knocking out(CKO)ATP6AP2 in the OB-lineage cells(Atp6ap2^(Ocn-Cre))reduced trabecular,but not cortical,bone formation and bone *** and cellular biochemical studies revealed that LRP6 and N-cadherin were reduced in ATP6AP2-KO BMSCs and OBs,but not *** in vitro and in vivo studies revealed impairedβ-catenin signaling in ATP6AP2-KO BMSCs and OBs,but not osteocytes,under both basal and Wnt stimulated conditions,although LRP5 was decreased in ATP6AP2-KO osteocytes,but not *** cell biological studies uncovered that osteoblastic ATP6AP2 is not required for Wnt3a suppression ofβ-catenin phosphorylation,but necessary for LRP6/β-catenin and N-cadherin/β-catenin protein complex distribution at the cell membrane,thus preventing their *** of activeβ-catenin diminished the OB differentiation deficit in ATP6AP2-KO *** together,these results support the view for ATP6AP2 as a critical regulator of both LRP6 and N-cadherin protein trafficking and stability,and thus regulatingβ-catenin levels,demonstrating an un-recognized function of osteoblastic ATP6AP2 in promoting Wnt/LRP6/β-catenin signaling and trabecular bone formation.

关键词： LRP6 impaired organs

A bifunctional POM-based Cu-viologen complex with mixed octamolybdate clusters for rapid oxidation desulfurization and effective photogeneration of hydrogen

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Rare Metals 2024年第1期43卷 236-246页

作者： lin Yang Zhong Zhang Chao-Nan Zhang xiu-li Wang College of Chemistry and Materials Engineering Bohai UniversityJinzhou 121013China Professional Technology Innovation Center of liaoning Province for Conversion Materials of Solar Cell Bohai UniversityJinzhou 121013China

The design and synthesis of catalysts for the oxidation desulfurization and production of hydrogen are extremely important for solving environmental pollution and energy ***,a novel bifunctional [α-Mo_(8)O_(26)]^(4-)/[β-Mo_(8)O_(26)]^(4-)-based Cu-viologen complex H_(4)[Cu_(2)~ⅠCl_(2)(Hbcbpy)_(4)] [α-Mo_(8)O_(26)] [β-Mo8O_(26)]·H_(2)O(BHU-2,Hbcbpy=1-(4-carboxybenzyl)-4,4'-bipyridinium) was synthesized and characterized by single-crystal X-ray diffraction(XRD),infrared radiation spectra,powder X-ray diffraction(PXRD) and X-ray photoelectron spectroscopy(XPS) *** structural characteristic of BHU-2 is the presence of two types of octamolybdate clusters [α-Mo_(8)O_(26)]^(4-)/[β-Mo_(8)O_(26)]^(4-)and a new binuclear Cu~Ⅰ-Hbcbpy complex linked by Cl-bridges[Cu_(2)ⅠCl_(2)(Hbcbpy)_(4)]^(4+).BHU-2 as a heterogeneous catalyst exhibits excellent activities to the oxidation desulfurization and photocatalytic hydrogen *** room temperature,BHU-2 can catalyze 96% conversion of methyl phenyl sulfide with 98% selectivity,and the process obeys the pseudo-first-order reaction kinetic with the half-life of9.6 *** notorious 2-chloroethyl ethyl sulfide can achieve 99% conversion with 98% selectivity within only1 min at the presence of BHU-2,and the turnover frequency(TOF) is up to 7400 h^(-1).BHU-2 also exhibits high catalytic activity for the oxidation of other aromatic and aliphatic thioethers within short time at room ***,BHU-2 shows a high catalytic activity for visible-light-driven hydrogen evolution with an H_(2) evolution rate of 1677.85 μmol·g^(-1)·h^(-1) within 10 ***,the catalytic activities do not decrease evidently after three cycles,revealing the prominent structural stability and recyclability.

关键词： Polyoxometalate Metal-organic complex Viologen Oxidation desulfurization Photocatalytic hydrogen production

Experimental Investigation on Vertical Hydraulic Transport of Ores in Deepsea Mining

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China Ocean Engineering 2024年第1期38卷 42-53页

作者： liU Lei liU Jian-cheng li Xin XU li-xin ZhanG xiu-zhan State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Sanya Yazhou Bay Institution of Deep-sea Sci-Tech Shanghai Jiao Tong UniversitySanya 572000China China Merchants Marine And Offshore Research Institute Co. Ltd.Shenzhen 518067China China Merchants Deepsea Research Institute(Sanya)Co. Ltd.Sanya 572000China School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

Deepsea mining has been proposed since the 1960s to alleviate the lack of resources on *** hydraulic transport of collected ores from the seabed to the sea surface is considered the most promising method for industrial *** the present study,an indoor model test of the vertical hydraulic transport of particles was conducted.A noncontact optical method has been proposed to measure the local characteristics of the particles inside a vertical pipe,including the local concentration and particle *** hydraulic gradient of ore transport was evaluated with various particle size distributions,particle densities,feeding concentrations and mixture flow *** transport,the local concentration is larger than the feeding concentration,whereas the particle velocity is less than the mixture *** qualitative effects of the local concentration and local fluid velocity on the particle velocity and slip velocity were *** local fluid velocity contributes significantly to particle velocity and slip velocity,whereas the effect of the local concentration is marginal.A higher feeding concentration and mixture flow velocity result in an increased hydraulic *** effect of the particle size gradation is slight,whereas the particle density plays a crucial role in the transport.

关键词： deepsea mining vertical hydraulic transport experiment flow characteristics

Numerical Study on the Aerodynamic and Fluid−Structure Interaction of An NREL-5MW Wind Turbine

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China Ocean Engineering 2024年第3期38卷 363-378页

作者： ZHAO Mi YU Wan-li WANG Pi-guang QU Yang DU xiu-li Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing 100124China State Key Laboratory of Bridge Engineering Safety and Resilience Beijing University of TechnologyBeijing 100124China

A 5-MW wind turbine has been modeled and analyzed for fluid-structure interaction and aerodynamic *** this study, a full-scale model of a 5-MW wind turbine is first developed based on a computational fluid dynamics(CFD) approach, in which the unsteady, noncompressible Reynolds Averaged Navier-Stokes(RANS) method is used. The main focus of the study is to analyze the tower shadow effect on the aerodynamic performance of the wind turbine under different inlet flow conditions. Subsequently, the finite element model is established by considering fluid/structure interactions to study the structural stress, displacement, strain distributions and flow field information of the structure under the uniform wind speed. Finally, the fluid-structure interaction model is established by considering turbulent wind and the tower shadow effect. The variation rules of the dynamic response of the one-way and two-way fluid-structure interaction(FSI) models under different wind speeds are analyzed, and the numerical calculation results are compared with those of the centralized mass model. The results show that the tower shadow effect and structural deformation are the main factors affecting the aerodynamic load fluctuation of the wind turbine, which in turn affects the aerodynamic performance and structural stability of the blades. The structural dynamic response of the coupled model shows significant similarity, while the structural displacement response of the former exhibits less fluctuation compared with the conventional centralized mass model. The one-way fluid-structure interaction(FSI)model shows a higher frequency of stress-strain and displacement oscillations on the blade compared with the two-way FSI model.

关键词： computational fluid dynamics methods(CFD) tower shadow effect aerodynamic performance fluidstructure interaction space flow field