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Arsenic uptake, accumulation and phytofiltration by duckweed (Spirodela polyrhiza L.)

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Journal of Environmental Sciences 2011年第4期23卷 601-606页

作者： Xin zhang Ying hu Yunxia Liu Baodong Chen State key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

This study investigates arsenic （As） accumulation and tolerance of duckweed Spirodela polyrhiza L. and its potential for As phytofiltration. S. polyrhiza was able to survive in high concentration of As（V） solution. The EC 50 values （± SE） based on the external As（V） were （181.66 ± 20.12） μmol/L. It accumulated （999 ± 95） mg As/kg dw when exposed in 320 μmol/L As（V） solution for one week, and was able to take up appropriately 400 mg As/kg dw in tissues without a significant biomass loss. The EC 50 values （the effective concentration of As（V） in the nutrient solution that caused a 50% inhibition on biomass production） was （866 ± 68） mg/kg dw for the tissues, indicating that S. polyrhiza had a high capability of As accumulation and tolerance. The uptake kinetic parameters V max was （55.33 ± 2.24） nmol/（g dw·min） and K m was （0.144 ± 0.011） mmol/L. Within 72 hr, S. polyrhiza decreased As concentration in the solution from 190 to 113 ng/mL with a removal rate of 41%. The study suggested that this floating aquatic plant has some potential for As phytofiltration in contaminated water bodies or paddy soils.

关键词： arsenic duckweed phytofiltration Spirodela polyrhiza L.

In situ measured growth rates of bainite plates in an Fe-C-Mn-Si superbainitic steel

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International Journal of Minerals,Metallurgy and Materials 2014年第4期21卷 371-378页

作者： zhang-wei hu Guang Xu Hai-jiang hu Li Wang Zheng-liang Xue Key Laboratory for Ferrous Metallurgy and Resources Utilization of the Ministry of Education Wuhan University of Science and Technology State Key Laboratory of Development and Application Technology of Automotive Steels (Baosteel Group)

The growth rates of bainite plates in an Fe-C-Mn-Si superbainitie steel were investigated by in situ observation. The lengthening rates of ferrite bainite during both cooling and isothermal holding processes were observed and the growth rates of bainite plates nucleating at grain boundaries, within grains and on preformed bainite were measured. It is indicated that the lengthening rates of bainite plates during the cooling and isothermal processes were different, and that the growth rates of bainite plates nucleating at different types of sites also demon- strated diversity. The bainite plates initiating at [vain boundaries during cooling grew the fastest, while the plates nucleating on preformed bainite did the slowest. However, the growth rate of the bainite plates nucleating at grain boundaries during isothermal transformation de- creased the most, whereas the bainite plates initiating within grains grew the fastest. In addition, the growth rate of ferrite bainite in the study supported the diffusion transformation mechanism of bainite from the viewooint of ~rowth rate.

关键词： bainitic steel bainite growth rate cooling isothermal treatment phase transitions

Structure optimization of gas-liquid combined loop reactor using a CFD-PBE coupled model

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Petroleum Science 2012年第3期9卷 379-388页

作者： Qi Nana zhang Kai Xu Gang Yang Yongping zhang hu School of Energy Power and Mechanical Engineering North China Electric Power UniversityBeijing 102206China School of Chemical Engineering University of AdelaideSouth AustraliaSA 5005Australia

Flow characteristics, such as flow pattern, gas holdup, and bubble size distribution, in an internal loop reactor with external liquid circulation, are simulated to investigate the influence of reactor internals by using the computational fluid dynamics （CFD）-population balance equations （PBE） coupled model. Numerical results reveal that introducing a downcomer tube and a draft tube can help to improve the mass and heat transfer of the reactor through enhanced liquid circulation, increased gas holdup and reduced bubble diameter. The hydrodynamic behavior in the internal loop reactor with external liquid circulation can be managed effectively by adjusting the diameter and axial position of the draft tube.

关键词： Loop reactor Structure optimization Hydrodynamics CFD-PBE coupled model

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高黏度苯-环己烯体系的萃取精馏分离研究

聚酯工业 2024年第5期37卷 27-30页

作者：张虎飞何伟孙超天津大港油田圣达科技有限公司天津300280 中国石油天然气集团公司青海油田分公司测试公司青海海西蒙古族藏族自治州茫崖816499

探索高黏度体系中物质分离的高效方法对化工领域具有重要意义。采用萃取精馏分离技术对苯与环己烯的混合物进行处理,旨在克服传统蒸馏技术在处理此类高黏度体系时的能耗高和分离效率低等问题。研究中引入低共熔溶剂(DES)作为萃取剂,通... 详细信息

探索高黏度体系中物质分离的高效方法对化工领域具有重要意义。采用萃取精馏分离技术对苯与环己烯的混合物进行处理,旨在克服传统蒸馏技术在处理此类高黏度体系时的能耗高和分离效率低等问题。研究中引入低共熔溶剂(DES)作为萃取剂,通过实验和模拟优化分离过程,确立最佳操作条件。实验结果显示,ChCl:Ur、ChCl:LA的相对挥发度分别为2.18、1.96,表明这两种DES在提高苯与环己烯的分离效率方面表现出色。综合可以看出,高黏度苯-环己烯体系的萃取精馏分离研究,成功提高了高黏度苯-环己烯体系的分离效率。这为化工领域处理类似高黏度混合物提供了一种有效的解决方案。

关键词：苯环己烯萃取精馏低共熔溶剂气液相平衡

中老年轻度认知功能障碍患者中医证候要素与MMSE及MoCA量表评分相关性研究

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中华中医药杂志 2024年第4期39卷 2021-2026页

作者：张虎第五永长杨谦王登坤刘奇周源陕西中医药大学第一临床学院咸阳712046 陕西中医药大学基础医学院咸阳712046

目的:探讨中老年轻度认知功能障碍(MCI)患者的中医证候要素与简易精神状态检查量表(MMSE)及蒙特利尔认知评估量表(MoCA)评分的相关性。方法:采取整群随机抽样方法,随机选取西咸主城区7个社区,以50~89岁中老年人群作为筛查对象,通过受筛... 详细信息

目的:探讨中老年轻度认知功能障碍(MCI)患者的中医证候要素与简易精神状态检查量表(MMSE)及蒙特利尔认知评估量表(MoCA)评分的相关性。方法:采取整群随机抽样方法,随机选取西咸主城区7个社区,以50~89岁中老年人群作为筛查对象,通过受筛人群的一般资料和病史,结合认知能力检测与规范的诊断标准,筛查出MCI患者。分析MCI患者的中医证候要素与MMSE及MoCA量表评分之间的相关性。结果:女性MCI患病人数多于男性;MCI的虚证病性证素分布频次为肾虚>髓减>阴虚>气虚>脾虚>阳虚>血虚。实证病性证素分布频次为痰浊>内热>血瘀>阳亢;MCI的中医证素以2种证素兼见(70/206,33.98%)及3种证素兼见(49/206,23.79%)为主;认知功能损害在MMSE量表中主要集中在注意力和计算力、结构能力、书写能力、延迟回忆等领域,在MoCA量表中主要集中在注意力、语言能力、视空间与执行功能及延迟回忆等领域;MMSE总分与阳亢呈负相关(P<0.05);即刻记忆得分与痰浊呈负相关(P<0.05);延迟回忆得分与髓减呈负相关(P<0.05);书写能力得分与髓减呈正相关(P<0.01);复述能力得分与内热呈正相关(P<0.05);阅读能力得分与血瘀呈负相关(P<0.05);结构能力得分与肾虚呈负相关(P<0.01)。MoCA总分与内热呈正相关(P<0.01);视空间与执行功能与内热呈正相关(P<0.01),与血瘀呈负相关(P<0.05);命名得分与髓减呈负相关(P<0.05);注意力得分与内热呈正相关(P<0.05),与血瘀呈负相关(P<0.05);语言能力得分与髓减呈负相关(P<0.05),与内热呈正相关(P<0.01)。结论:中老年MCI患者的中医证素主要集中在肾虚、髓减、内热、痰浊等,是多种病理因素相互作用的结果,MCI与中医证候要素之间存在一定的相关关系,但研究结论尚未统一,还需要进一步研究。

关键词：轻度认知功能障碍阿尔茨海默病中医证素认知域相关性分析神经心理学量表

Effect of Trace O Element on High-temperature Wettability Between Ni_3Al Melt and Y_2O_3 Ceramic

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Acta Metallurgica Sinica(English Letters) 2018年第5期31卷 552-560页

作者： Peng Bai hua-Rui zhang Bei-Bei Wan Chao Ran hu zhang School of Materials Science and Engineering Beihang University Beijing Key Laboratory for Advanced Functional Material and Thin Film Technology Beihang University

Effect of trace O element on the high-temperature wettability between Ni3Al scrap melt and Y2O3 ceramic at 1873 K is investigated. With the increase in O content in Ni3Al scrap melt from 6 to 21 ppm, the equilibrium contact angle decreases from 93.3° to 88.9°. The initial surface tension and adhesive work of molten Ni3Al scrap drop from 3153.5 to 807.4 mN m^-1 and from 2974.6 to 882.2 mN m^-1, respectively. The average spreading rate increases from 0.03° s^-1 to 0.17° s^-1. The whole wetting processes are divided into four periods. The main driving force for spreading in period（1） is the adsorption and diffusion of active atoms around the interface. Trace O content in Ni3Al scrap has a significant impact on interfacial reactions which mostly take place in the second stage, and can accelerate the spreading process on Y2O3 substrate. The reaction products during wetting process are Y3Al5O12, YAlO3 and Al2O3.

关键词： Ni3Al scrap Wetting Interaction Yttria Oxygen content

烧结NdFeB磁体表面Zn-Al/T8超疏水复合涂层的显微组织及耐蚀性

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Transactions of Nonferrous Metals Society of China 2024年第5期34卷 1606-1617页

作者：张晓虎罗军明徐吉林陈金黄俊马永存薛名山南昌航空大学材料科学与工程学院南昌330063

为提升烧结NdFeB磁体的耐蚀性,采用旋涂法和等离子体增强化学气相沉积技术在其表面制备Zn-Al/T8(2-全氟辛基乙基丙烯酸酯)超疏水复合涂层。结果表明,Zn-Al涂层主要由片层状的Zn和Al相组成,厚度大约为28μm。Zn-Al/T8复合涂层的接触角达... 详细信息

为提升烧结NdFeB磁体的耐蚀性,采用旋涂法和等离子体增强化学气相沉积技术在其表面制备Zn-Al/T8(2-全氟辛基乙基丙烯酸酯)超疏水复合涂层。结果表明,Zn-Al涂层主要由片层状的Zn和Al相组成,厚度大约为28μm。Zn-Al/T8复合涂层的接触角达到151.78°,而滚动角仅为5.13°,说明Zn-Al/T8复合涂层可提供一个超疏水表面。Zn-Al涂层和Zn-Al/T8复合涂层对烧结NdFeB的磁性能均无显著影响。Zn-Al涂层通过牺牲阳极来提高NdFeB磁体的耐蚀性,而Zn-Al/T8复合涂层通过超疏水表面进一步提升耐蚀性。Zn-Al/T8复合涂层较Zn-Al涂层具有更好的耐盐雾性能。Zn-Al/T8超疏水复合涂层是一种非常有前途的烧结NdFeB磁体保护涂层。

关键词：显微组织耐蚀性烧结NdFeB磁体 Zn-Al涂层超疏水表面旋涂法等离子体增强化学气相沉积

Effect of Open Porosity of Y2O3 Ceramic on the Apparent Contact Angles and Interactions Between Ti47Al Alloys and Y2O3 Ceramic

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Acta Metallurgica Sinica(English Letters) 2017年第5期30卷 456-463页

作者： Chao Ran hua-rui zhang hu zhang Bei-bei Wan Peng Bai School of Materials Science and Engineering BeihangUniversityBeijing 100191China Beijing Key Laboratory for Advanced Functional Materialand Thin Film Technology Beihang UniversityNo.37 Xueyuan RoadBeijing 100191China

The effect of open porosity of Y2O3ceramic on the apparent contact angle and interaction between molten Ti47 Al alloy and Y2O3ceramic substrates under pure Ar was investigated by using a sessile drop method at 1600 °C. As the open porosity increased from 9.6% to 30.3%, the spreading rate of molten Ti47 Al alloys on Y2O3ceramic substrates reduced from 2.3 to 1.1°/s; meanwhile, the final equilibrium contact angles increased from 55.8° to 63.6°. The microstructure observations revealed that with increasing the open porosity of the Y2O3substrates, the thickness of sand adhesion at the interfaces of the alloy droplets increased from 5.4 to 15.7 lm, and ceramic particles in the alloy matrix increased as well. The increasing contact area between the molten alloy and the substrate played a dominant role in determining the interaction on Ti Al/Y2O3interface.

关键词： Contact angle Yttria Titanium aluminides Interaction Open porosity

Elastic scattering of ^(13)C and ^(14)C isotopes on a ^(208)Pb target at energies of approximately five times the Coulomb barriers

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Chinese Physics C 2024年第3期48卷 65-71页

作者：杨过段芳芳王康杨彦云孙志宇 Valdir Guimarães 庞丹阳陈文棣金磊许世伟马军兵马朋白真汪凌昊刘泉王惠仁吕冰锋郭松 Mukhi Kumar Raju 王秀华李荣华张玉虎周小红胡正国徐瑚珊 CAS Key Laboratory of High Precision Nuclear Spectroscopy Institute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100080China Instituto de Física Universidade de São PauloRua do Matão1371São Paulo 05508-090SPBrazil School of Physics and Beijing Key Laboratory of Advanced Nuclear Materials and Physics Beihang UniversityBeijing 100191China School of Physics Science and Engineering Tongji UniversityShanghai 200092China School of physics and Optoelectronic Engineering Anhui UniversityHefei 230601China Department of Physics GITAM School of ScienceGITAM UniversityVisakhapatnam 530045India

The elastic scattering angular distributions of ^(13)C at 340 MeV and ^(14)C at 294 MeV and 342 MeV on a ^(208)Pb target,which correspond to approximately five times the Coulomb barriers,were measured at the Radioactive Ion Beam Line in *** data were analyzed within the optical model and continuum-discretized coupled-channels(CDCC)framework,and the results of both calculations could effectively account for the experimental *** differential cross sections of elastic scattering revealed no particular suppression at the Coulomb nuclear interference peak angles,suggesting that the breakup coupling effects on the elastic scattering angular distributions were negligibly small in this incident energy *** contributions from the couplings with inelastic states to the elastic cross sections were of minor importance within the angular range covered by these experiments.

关键词： elastic scattering radioactive ion beam angular distribution optical model coupling effects