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活动理论视角下TPACK发展过程的动态分析——以美国grits教育实习生研究项目为例

中国信息技术教育 2016年第12期 90-93页

作者：王云雪杨絮张海白晶东北师范大学计算机科学与信息技术学院东北师范大学留日预备校东北师范大学传媒科学学院东北师范大学附属中学净月实验幼儿园

TPACK理论作为一项革新性教育技术理论,已经获得了广泛的认可,但在实践中缺点也很明显,即对真实的复杂教育现场而言,还缺乏较为实用和动态的解释框架。很多学者已经对此问题进行了大量有益的探索,这其中的努力主要包括TPACK实践框架和TP... 详细信息

TPACK理论作为一项革新性教育技术理论,已经获得了广泛的认可,但在实践中缺点也很明显,即对真实的复杂教育现场而言,还缺乏较为实用和动态的解释框架。很多学者已经对此问题进行了大量有益的探索,这其中的努力主要包括TPACK实践框架和TPACK活动分析法等。TPACK活动分析法是基于活动理论视角,对TPACK发展过程的动态分析。

关键词：活动理论 grits TPACK 动态分析教育技术理论活动分析革新性理论分析法实践框架实证性研究

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Polycrystalline diamond mini-cubes for sawing applications

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金刚石与磨料磨具工程 2008年第S1期28卷 83-87页

作者： Sung James C. Chang Kuen-liang Tso Pei-lum Hsu Kai-hung Sung Michael KINIK Company 64Chung-San Rd.Ying-Kuo National Taiwan University National Taipei University of Technology PME Dept.National Tsing Hua University Advanced Diamond Solutions Inc.351 King Street Suite 813San FranciscoCA 94158U.S.A.

Diamond grits are indispensable for sawing granite or *** year about 1 000 tons of diamond grits are consumed for such *** all cases,mono crystalline diamond is ***, polycrystalline grits(polygrits) are generally better performed than mono grits as *** example,poly grits of cubic boron nitride(***(?) CBN-550 of Diamond Innovations) can cut faster and they last longer than mono grits(***(?) CBN-500). Polygrits of alumina(***(?) of 3M) also out perform by far glassy grits(*** alumina).For diamond superabrasives,micron polygrits formed by shock waves may polish as fast as mono grits of the same size,but without causing as much scratches due to the presence of smaller sintered *** improved performance of poly grits is attributed to their ability to micro chipping that renews the sharp cutting corners from time to *** contrast,mono grits tend to round off at low cutting force or macro fracture at high cutting force,so they may lose the cutting ability rapidly. For sawing granite with mesh sizes 40/50 or coarser,poly grits of diamond have not been available until *** this research,we have made polygrits in mini cube with sizes of 18/20,20/25,and 30/*** grinders and wire saws were made by brazing both mono grits and polygrits on steel *** performance on granite demonstrated that grinding speed was faster with turbo grinder,and the surface finish was smoother with wire saw for poly grits than mono ones. Polygrits and mono grits of diamond were mixed for comparison(upper left).Polygrits of mini cubes were brazed on the pearl of a wire saw(upper right).Mono diamond grits were brazed on a turbo grinder(bottom diagrams ).

关键词： granite sawing diamond grits polygrits turbo grinder wire saw

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Ultrahigh pressure sintering of polycrystalline diamond cubes

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金刚石与磨料磨具工程 2008年第S1期28卷 70-76,79页

作者： Hu Shao-Chung Chang Kuen-Liang Sung James C. Tso Pei-Lum Hsu Kai-Hung Sung Michael KINIK Company 64Chung-San Rd.Ying-Kuo National Taipei University of Technology National Taiwan University PME Dept.National Tsing Hua University Advanced Diamond Solutions Inc.351 King Street Suite 813San FranciscoCA 94158U.S.A.

Polycrystalline grits(polygrits) have been used widely in industry as *** to their higher impact strength and the friable nature,polygrits are more endurable and more efficient than monocrystal grits (monogrits) in material removal *** example,polygrits of alumina may last longer and cut faster than ***,polygrits of cubic boron nitride is a superior superabrasive than monogrits of the same. Although diamond superabrasives have been indispensable for constructional sawing applications and industrial grinding applications,there has no polygrits of diamond that are commercially *** this research,we used a novel technology to sinter micron diamond fines to form polygrits of *** characterization demonstrated that polygrits of diamond can be tough to withstand *** due to the presence of micro grains,the grit can sharpen itself without dulling by shedding the worn *** paper revealed many examples of using diamond polygrits.

关键词： PCD superabrasives diamond grits CMP pad conditioners

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Assessment of Microbial Changes and Nutritional Qualities of Extruded White Yam (<i>Dioscorea rotundata</i>) and Bambara Groundnut (<i>Vigna subterranean</i>) Blends

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Food and Nutrition Sciences 2013年第1期4卷 100-107页

作者： O. B. Oluwole S. O. Awonorin F. Henshaw G. N. Elemo O. A. T. Ebuehi Department of Biochemistry University of Lagos Lagos Nigeria. Department of Food Science and Technology Federal University of Agriculture Abeokuta Nigeria Food and Analytical Services Department Federal Institute of Industrial Research Oshodi Nigeria

Two flavoured extruded products were developed by co-extruding yam grits (750 μm) obtained from white yam (Dioscorea rotundata) and bambara groundnut flour (250 μm) in 160:40 respectively obtained from white bambara groundnut with added flavouring agents of salt (1% - 3%) and sugar (4% - 6%) in the feed blends at screw speed of 70 rpm, 17.5%, feed moisture and at the barrel temperature of 145℃. The extruded products were packaged in low density polyethylene bag (0.02 μm gauge size) and stored at room temperature (28℃ ± 2℃) and at refrigeration temperature (9℃ ± 2℃) for a period of twenty weeks. The microbiological changes in the extruded products as determined by the total plate under both storage conditions showed that maximum total plate counts were 0.5 × 104 and 5.4 × 104 cfu/g at 9℃ ± 2℃ and 28℃ ± 2℃ respectively. Nutritional evaluation studies of extrudates were comparable (p ≥ 0.05) with standard casein diet with minimum crude protein content of 13.51% providing 1707.2 KJ energy per 100gof diet and supported weight gain and growth of laboratory animals.

关键词： Co-Extrude Yam grits Bambara Flour Total Plate Count Nutritional Evaluation Weight Gain Growth

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Effect of Seed Size, Suspension Recycling and Substrate Pre-Treatment on the CVD Growth of Diamond Coatings

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Open Journal of Applied Sciences 2015年第12期5卷 747-763页

作者： Awadesh Kumar Mallik Sandip Bysakh Radhaballabh Bhar Shlomo Z. Rotter Joana Catarina Mendes CSIR-Central Glass & Ceramic Research Institute Kolkata India Department of Instrumentation Science Jadavpur University Kolkata India Instituto de Telecomunicaç õ es Campus Universitário de Santiago Aveiro Portugal

CVD growth of uniform conformal polycrystalline diamond (PCD) coatings over complex three dimensional structures is very important material processing technique. It has been found that the nucleation and subsequent growth period is very critical for successful development of CVD diamond based technologies. There are many methods of enhancing diamond nucleation on foreign substrates-ultrasonic treatment with diamond seed suspension being the best among them. A combination of ultrasonic seeding (US) technique with prior treatment (PT) of the substrate under CVD diamond growth conditions for brief period of time, has found to be very effective in enhancing the diamond nucleation during CVD growth—together they are known as NNP. But successive usage of the same seeding suspension up to ten cycles deteriorates the seeding efficiency. 6th seeding cycle onwards the silicon substrates are barely get covered by diamond crystallites. Five different diamond micron grits were used for seeding the silicon substrates and it is observed that US with the sub-micron particles (0.25 μm) is very effective in efficient nucleation of PCD on Si substrates. PT of the substrate somewhat negates the effect of successive use of the same seeding slurry but it is best to avoid recycling of the same seeding suspension using micron size diamond grits.

关键词： Microwave Plasma CVD Seeding Diamond Micron grits Novel Nucleation Process (NNP) Polycrystalline Diamond

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