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指向“三会”发展的数学形类表征教学实践探究 被引量:1
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作者 李坚 孙红英 《教学与管理》 2023年第32期36-41,共6页
数学核心素养主要集中在“三会”上,即“会用数学的眼光观察现实世界、会用数学的思维思考现实世界、会用数学的语言表达现实世界。”然而,怎样让“三会”落地生根,当前广大教师还缺少有效的实践策略。运用数学表征特别是“形类表征”... 数学核心素养主要集中在“三会”上,即“会用数学的眼光观察现实世界、会用数学的思维思考现实世界、会用数学的语言表达现实世界。”然而,怎样让“三会”落地生根,当前广大教师还缺少有效的实践策略。运用数学表征特别是“形类表征”可以让学生数学核心素养的发展找到“抓手”,获得“媒介”。基于相关理论和实践,在指向“三会”发展的数学形类表征教学实践中,应遵循如下理念与策略:引导学生善于从表征观察中发现问题、揭示本质、形成结构,以培养敏锐、深邃与长远的数学眼光;引导学生善于从表征思考中严密逻辑、协同创新,以培养高阶数学思维;引导学生善于从表征表达中迁移经验、类比联想、关联拓展,以培养严谨缜密、清晰准确与系统逻辑的数学语言。 展开更多
关键词 核心素养 “三会” 形类表征 表征观察 表征思考 表征表达
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增强职业教育适应性的逻辑内涵、观察表征及实践路径 被引量:5
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作者 李春鹏 陈正振 《教育与职业》 北大核心 2022年第22期34-38,共5页
增强职业教育适应性是构建高质量职业教育体系的本质要求,也是一个系统复杂的工程。增强职业教育适应性需要从本源上理解其逻辑内涵,从主客体、时间、空间、结构等多方面予以评价,构建宏观、中观、微观三个层面的观察表征,通过进一步落... 增强职业教育适应性是构建高质量职业教育体系的本质要求,也是一个系统复杂的工程。增强职业教育适应性需要从本源上理解其逻辑内涵,从主客体、时间、空间、结构等多方面予以评价,构建宏观、中观、微观三个层面的观察表征,通过进一步落实新职教法,提升现代职业教育体系的适应性;强化省级政府的主体责任,提升职业教育与区域经济社会发展的适应性;凸显企业在职业教育人才培养决策中的地位,提升职业教育人才培养与产业发展的适应性;创新职业教育发展模式,提升职业教育人才培养的适应性。 展开更多
关键词 职业教育适应性 逻辑内涵 观察表征 实践路径
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Fluoride Removal by Lanthanum Alginate Bead: Adsorbent Characterization and Adsorption Mechanism 被引量:2
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作者 霍亚坤 丁文明 +2 位作者 黄霞 徐静年 赵梦华 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第3期365-370,共6页
Lanthanum alginate bead is a new, highly active adsorbent. In the present study, we investigated its ad- sorption performance and its adsorption mechanism. The adsorption isotherm for fluoride onto lanthanum alginate ... Lanthanum alginate bead is a new, highly active adsorbent. In the present study, we investigated its ad- sorption performance and its adsorption mechanism. The adsorption isotherm for fluoride onto lanthanum alginate b ead fits the Langmuir model well, and the maximum adsorption capacity is 197.2 mg·g-1. X-ray diffraction shows the amorphous nature of lanthanum alginate bead, which allows for better accessibility to fluoride and thus better activity. Infrared spectra of lanthanum alginate bead before and after adsorption confirm its stable skeletal structure. Scanning electron microscopy shows that the dense surface structure of the adsorbent appear cracks after adsorption. T he adsorption mechanism of lanthanum alginate bead is considered as an ion exchange between F- and Cl- or OH-, as verified from the adsorbent and the solution by pH effect, energy dispersive X-ray, and ion chromatography. 展开更多
关键词 lanthanum alginate fluoride removal adsorbent characterization adsorption mechanism ion exchange
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OBSERVATION AND ANALYSIS OF SEA SURFACE WIND OVER THE QIONGZHOU STRAIT
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作者 许向春 辛吉武 +3 位作者 梁国锋 邢绪煌 陈有龙 谢寒生 《Journal of Tropical Meteorology》 SCIE 2010年第4期402-408,共7页
The spatial variation and diurnal fluctuation of sea surface wind over the Qiongzhou Strait were described using verified datasets from automatic weather stations on board a ferry, buoys, and on the coast. Results are... The spatial variation and diurnal fluctuation of sea surface wind over the Qiongzhou Strait were described using verified datasets from automatic weather stations on board a ferry, buoys, and on the coast. Results are as follows: (1) On average, sea surface wind speed is 34 m/s larger over the Qiongzhou Strait than in the coastal area. Sea surface wind speeds of 8.0 rrds or above (on Beaufort scale five) in the coastal area are associated with speeds 5-6 m/s greater over the surface of the Qiongzhou Strait. (2) Gust coefficients for the Qiongzhou Strait decrease along with increasing wind speeds. When coastal wind speed is less than scale five, the average gust coefficient over the sea surface is between 1.4 and 1.5; when wind speed is equal to scale five or above, the average gust coefficient is about 1.35. (3) In autumn and winter, the diurnal differences of average wind speed and wind consistency over the strait are less than those in the coastal area; when wind speed is 10.8 m/s (scale six) or above, the diurnal difference of average wind speed decreases while wind consistency increases for both the strait and the coast. 展开更多
关键词 Qiongzhou Strait sea surface wind observational analysis statistical characteristics
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Atomic-scale observation of the deformation and failure of diamonds by in-situ double-tilt mechanical testing transmission electron microscope holder 被引量:2
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作者 Yizhi Zhang Yeqiang Bu +4 位作者 Junquan Huang Tianye Jin Anmin Nie Hongtao Wang Yongjun Tian 《Science China Materials》 SCIE EI CSCD 2020年第11期2335-2343,共9页
In-situ transmission electron microscopy(TEM)has been demonstrated to be a powerful method in resolving challenging problems such as interactions among various defects.To take advantage of the atomic resolution of adv... In-situ transmission electron microscopy(TEM)has been demonstrated to be a powerful method in resolving challenging problems such as interactions among various defects.To take advantage of the atomic resolution of advanced TEMs,a compact five-degree-of-freedom nanomanipulator was integrated with an indenter that was made of nanotwinned diamonds,for both the in-situ mechanical testing and double tilting of TEM samples.As a demonstration,in-situ bending tests were performed on the?111?,?110?and?100?single-crystal diamond needles.The tests revealed the{111}cleavage to be the dominant failure mode.The in-situ indentation on a diamond nanoplate led to curved cracks consisting of nanometer-scale steps,which were identified to be atomic flat{111}facets.The atomic-scale observation of the deformation and failure of diamonds demonstrated the stability of the entire system and the durability of the indenter.We expect that more delicate research can be carried out by means of this holder in the near future,including in-situ stimulation,atomic characterization,and tomography. 展开更多
关键词 mechanical testing holder double tilt DIAMOND in situ TEM TOMOGRAPHY
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Synthesis and TEM structural characterization of C60-flattened carbon nanotube nanopeapods
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作者 Qing Wang Ryo Kitaura +2 位作者 Yuta Yamamoto Shigeo Arai Hisanori Shinohara 《Nano Research》 SCIE EI CAS CSCD 2014年第12期1843-1848,共6页
A fully flattened carbon nanotube (FNT), a graphene nanoribbon (GNR) analogue, provides a hollow space at edges for endohedral doping. Due to the unique shape of the hollow space of FNTs, novel types of low-dimens... A fully flattened carbon nanotube (FNT), a graphene nanoribbon (GNR) analogue, provides a hollow space at edges for endohedral doping. Due to the unique shape of the hollow space of FNTs, novel types of low-dimensional arrangements of atoms and molecules can be obtained through endohedral doping into FNTs, which provides a new type of nanopeapods. FNT-based nanopeapods have been synthesized through endohedral doping of C60, and their structural characterization with transmission electron microscopy (TEM) performed. The doping of C60 into the inner hollow space of FNTs has been carried out via the gas-phase filling method, where open-ended FNTs are sealed in a glass ampoule and heated at 723-773 K for two days. TEM observations show that most of the encapsulated C60 molecules align as single molecular chains along the edges of FNTs and that some of the C60 forms two-dimensional close-packed structures inside FNTs. 展开更多
关键词 carbon nanotubes nanopeapods endohedral doping electron microscopy
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