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Tribological Performance of Different Concentrations of Al_(2)O_(3)Nanofluids on Minimum Quantity Lubrication Milling

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Chinese Journal of Mechanical Engineering 2023年第4期36卷 67-78页

作者： xiufang Bai Juan Jiang Changhe Li Lan dong Hafiz Muhammad Ali Shubham Sharma School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao 266520China School of Mechanical and Electrical Engineering Qingdao Binhai UniversityQingdao 266555China Mechanical Engineering Department King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia Department of Mechanical Engineering IK Gujral Punjab Technical UniversityMain Campus-KapurthalaJalandhar 144603India

Nanofluid minimum quantity lubrication(NMQL)is a green processing technology.Cottonseed oil is suitable as base oil because of excellent lubrication performance,low freezing temperature,and high yield.Al_(2)O_(3)nanoparticles improve not only the heat transfer capacity but also the lubrication performance.The physical and chemical proper-ties of nanofluid change when Al_(2)O_(3)nanoparticles are added.However,the effects of the concentration of nanofluid on lubrication performance remain unknown.Furthermore,the mechanisms of interaction between Al_(2)O_(3)nanoparti-cles and cottonseed oil are unclear.In this research,nanofluid is prepared by adding different mass concentrations of Al_(2)O_(3)nanoparticles(0,0.2%,0.5%,1%,1.5%,and 2%wt)to cottonseed oil during minimum quantity lubrication(MQL)milling 45 steel.The tribological properties of nanofluid with different concentrations at the tool/workpiece interface are studied through macro-evaluation parameters(milling force,specific energy)and micro-evaluation parameters(surface roughness,micro morphology,contact angle).The result show that the specific energy is at the minimum(114 J/mm^(3)),and the roughness value is the lowest(1.63μm)when the concentration is 0.5 wt%.The surfaces of the chip and workpiece are the smoothest,and the contact angle is the lowest,indicating that the tribological proper-ties are the best under 0.5 wt%.This research investigates the intercoupling mechanisms of Al_(2)O_(3)nanoparticles and cottonseed base oil,and acquires the optimal Al_(2)O_(3)nanofluid concentration to receive satisfactory tribological properties.

关键词： Milling Al_(2)O_(3)nanofluid Minimum quantity lubrication(MQL) Surface micromorphology

Research on multi-parametric sensors based on multi-mode microfiber

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Optoelectronics Letters 2024年第1期20卷 18-22页

作者： dong Taiji LIU Xu WANG Yunkai GAO Bingkun JIANG Chunlei WANG xiufang College of Electrical and Information Engineering Northeast Petroleum UniversityDaqing 163318China

A multi-parametric sensor based on multi-mode microfiber(MMF)is proposed,utilizing the modal interference between HE11mode and HE12mode in the elongated multi-mode fiber to achieve the temperature and pressure measurement.In this paper,the simulation model of modal interference based on MMF is established and the mechanism of modal interference is analyzed.Using the different mechanisms of modal response in the fiber at different wavelengths,the temperature was inverted using the offset of wavelengths in the spectrum,and the pressure was measured using the change of light intensity.The independent measurement of temperature and pressure was achieved.The experimental results show that the sensor has a temperature sensitivity of 1.305 nm/℃.In the case of pressure sensing,the sensor shows a sensitivity of-0.163 d Bm/g.

关键词： measurement mode modal

Synthesis and Characterization of Hollow Strontium Carbonate Pompons by Composite Soft Template Method

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Journal of Wuhan University of Technology(Materials Science) 2023年第6期38卷 1434-1439页

作者： LI Bibo dong xiufang LI Yu SONG Jian XIE Wuxi ZHANG Wei LIU Yunfei School of Environment and Safety Engineering North University of ChinaTaiyuan 030051China School of Chemical Engineering and Technology North University of ChinaTaiyuan 030051China Xi'an Modern Chemistry Research Institute Xi'an 710065China

The hollow strontium carbonate pompons was synthesized for the first time by a controlled reaction precipitation method with sodium dodecyl benzene sulfonate(SDBS)and polyvinyl pyrrolidone(PVP)work together as template.The sampled particles were characterized by scanning electron microscopy(SEM),transmission electron microscopy(TEM),nitrogen adsorption-desorption measurement,X-ray diffraction(XRD),Energy dispersive X-Ray spectroscopy(EDX),Fourier transform infrared spectroscopy(FTIR),Thermogravimetric analysis and differential scanning calorimetry(TGA-DSC),etc.It is shown that the assynthesized hollow strontium carbonate pompons with the size of about 2μm consist of flake-like particles under the optimal reaction conditions.The formation mechanism of hollow strontium carbonate pompons was preliminarily explored.

关键词： strontium carbonate hollow structure pompons composite soft template method

从引入事件到引入评价:汉语中承接性副词或连词的主观化

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汉语学报 2023年第4期 76-85页

作者：董秀芳北京大学中国语言文学系/北京大学中国语言学研究中心 100871

承接副词“就”可以连接两个相继发生的事件,构成“VP_1就VP_2”的形式,由此还可以发展出条件关系。经过主观化,“就”后可以引入说话人的主观评价性成分,经常出现的评价性成分是“好”。“VP就好”原来是复句,但由于作为第二个小句的... 详细信息

承接副词“就”可以连接两个相继发生的事件,构成“VP_1就VP_2”的形式,由此还可以发展出条件关系。经过主观化,“就”后可以引入说话人的主观评价性成分,经常出现的评价性成分是“好”。“VP就好”原来是复句,但由于作为第二个小句的“好”在形式上比较短小,复句经过小句整合有可能被重新分析为单句。其中的“就好”由于高频连用有了词汇化倾向,向表示祈愿的语气词演变。汉语史上其他一些承接性副词或连词也发生了类似的演变,比如“即”“便”“才”“则”等。这表明联接性成分从引入客观的事件到引入主观评价在汉语中是一种比较常见的演变路径,进而又可能引发评价性成分与联结性成分的词汇化和语法化。

关键词：主观化承接副词连词小句整合词汇化

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汉语方式存在句的性质、特点与历史来源

中国语文 2022年第5期 560-572,639页

作者：董秀芳北京大学中文系/中国语言学研究中心/计算语言学教育部重点实验室北京

汉语中“处所+V着+NP”这一类句式在表达某处所存在某事物的同时也表示出了存在的方式,可以称为“方式存在句”。“有”字存在句是单纯的表示存在,而方式存在句体现了汉语存在表达的特点,在英语中没有严格的对应句式。方式存在句中的动... 详细信息

汉语中“处所+V着+NP”这一类句式在表达某处所存在某事物的同时也表示出了存在的方式,可以称为“方式存在句”。“有”字存在句是单纯的表示存在,而方式存在句体现了汉语存在表达的特点,在英语中没有严格的对应句式。方式存在句中的动词没有明确的施事,由以处所为话题、表示动作行为的操作说明句演变而来,通过转喻机制,由指动作行为变为指动作行为所造成的结果状态。在这一演变过程中,施事的不出现起了关键作用。施事不出现会导致动词从表示动作行为变为表示状态或方式。方式存在句的特点和形成过程反映了话题结构和方式要素在汉语语法表达中的重要性。

关键词：存在句方式话题结构施事句法演变

Synthesis and characterization of super paramagnetic composite photocatalyst-Titania/silica/nickel ferrite

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Particuology 2011年第5期9卷 475-479页

作者： Yu Li Xiufang Dong Junping Li School of Chemical Engineering and Environment North University of China Taiyuan 030051 Shanxi China

Composite photocatalysts with TiO2 porous shell and magnetic core were synthesized by using NiFe2O4 as a magnetic core, SiO2 as an intermediate layer and polyethylene glycol with molecular weight of 1000 （PEG 1000） as a template direction agent. The samples were characterized with N2 adsorption-desorption, X-ray diffraction （XRD）, transmission electron microscopy （TEM）, scanning electron microscopy （SEM）, vibrating sample magnetometry （VSM） and ultraviolet-visible （UV-vis） spectroscopy. The results showed that the obtained composites are spherical particles about 50 nm in diameter. The mesoporous TiO2 with magnetic core calcined at 350 ℃, 450 ℃, and 550 ℃ was found to have, respectively, different specific surface areas （94, 86, and 68 m^2/g） and average pore sizes （1.4, 2.2, and 2.8 nm）. The photocatalytic activity was investigated for degradation of nitrobenzene under UV irradiation. Nitrobenzene was decomposed in 300 min under irradiation of an 8 W UV lamp with a peak wavelength of 253.7 nm. The composite nanoparticles exhibited high photocatalytic efficiency and super paramagnetic nature for cleaning polluted water by magnetic separation.

关键词： Titania Mesoporous Photocatalyst Core-shell

Co-Ni Electromagnetic Coupling in Hollow Mo_(2)C/NC Sphere for Enhancing Electromagnetic Wave Absorbing Performance

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Chinese Journal of Chemistry 2023年第1期41卷 64-74页

作者： xiufang Yang Wenming Gao Jiamin Chen Xing Lu dong Yang Yifan Kang Qi Liu Yuchang Qing Wenhuan Huang Key Laboratory of Chemical Additives for China National Light Industry College of Chemistry and Chemical EngineeringShaanxi University of Science and TechnologyXi'anShaanxi 710021China Northwest Institute of Mechanical and Electrical Engineering XianyangShaanxi 712099China State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi'anShaanxi 710072China

For enhancing the electromagnetic wave(EW)attenuation and adsorption,rational constructing and homogeneously distributing bimetallic electromagnetic coupling units in hollow structure is an effective way,but hard to achieve.Herein,a CoNi-doped hybrid zeolite imidazole framework was synthesized as precursor,which was further converted into a hollow CoNi-bimetallic doped molyb-denum carbide sphere(H-CoNi@MoC/NC)through a two-step etching and calcination strategy.At the loading amount of 15 wt%,a strong absorption of minimum reflection loss(RL_(min))of-60.05 dB at 7.2 GHz with the thickness of 3.1 mm and a wide effective ad-sorption bandwidth(EAB)of 3.52 GHz at the thickness of 2.5 mm were achieved,which was far beyond the reported MoC-based metallic hybrids.The crucial synergistic Co-Ni electromagnetic coupling effect in the composite was characterized,not only enhanc-ing the dipolar/interfacial polarization,but also promoting the impedance matching,displaying the optimized EW absorbing perfor-mance.

关键词： Electromagnetic wave absorbing materials Hollow structure Hybrid zeolite imidazolate frameworks Microwave absorption Electromagnetic coupling

维普期刊数据库评论

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汉藏语系语言的评价性形态

民族语文 2021年第2期 3-14页

作者：董秀芳北京大学中文系北京100871 北京大学中国语言学研究中心北京100871 北京大学计算语言学教育部重点实验室北京100871

评价性形态包括指小、增量、贬化、褒化、表敬等,主要功能在于表达说话人对于事物、性质或行为等的主观评价和态度。本文考察了汉藏语系语言评价性形态的表现形式和功能,指出评价性形态具有多种表达手段,在词类上有比较广泛的分布,功能... 详细信息

评价性形态包括指小、增量、贬化、褒化、表敬等,主要功能在于表达说话人对于事物、性质或行为等的主观评价和态度。本文考察了汉藏语系语言评价性形态的表现形式和功能,指出评价性形态具有多种表达手段,在词类上有比较广泛的分布,功能上也发展得比较成熟,因此得出汉藏语系语言评价性形态比较凸显的结论,这也表明汉藏语系语言的主观性凸显。建议今后对汉藏语系的研究中加强对评价性形态的描写和分析。

关键词：汉藏语系语言词法评价性形态类型学主观性

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汉语语篇中的插叙标记及其演变

汉语学报 2020年第1期 33-42页

作者：董秀芳北京大学中文系北京大学中国语言学研究中心 100871

本文考察了不同历史时期汉语语篇中的插叙标记及其演变。上古时期,语篇中的插叙标记是"初",近代汉语中的插叙标记主要是"原来"(最初写作"元来")。这两个插叙标记原本都是指示过去时间的,而且指示的是起始时间。"原来"从插叙标记用法中... 详细信息

本文考察了不同历史时期汉语语篇中的插叙标记及其演变。上古时期,语篇中的插叙标记是"初",近代汉语中的插叙标记主要是"原来"(最初写作"元来")。这两个插叙标记原本都是指示过去时间的,而且指示的是起始时间。"原来"从插叙标记用法中获得了解释功能,并逐渐句法化,变为一个句子层面的副词。本文还讨论了"初"与"昔"的差异,指出词汇语义相近的成分可能发展出不同的篇章功能。

关键词：话语标记插叙叙事语篇句法化副词