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五小活动进阶课程的融合式校本探索 被引量:2
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作者 姜栋强 《中学物理》 2022年第24期28-33,共6页
“小发现、小制作、小发明、小实验、小创客”是东洲中学在“情智物理”研究过程中形成的特色活动,并开发为可进阶的融合式校本课程.“小发现”为初阶活动,“小发明”为中阶活动,“小创客”为高阶活动.“小制作”为初阶向中阶进阶做技... “小发现、小制作、小发明、小实验、小创客”是东洲中学在“情智物理”研究过程中形成的特色活动,并开发为可进阶的融合式校本课程.“小发现”为初阶活动,“小发明”为中阶活动,“小创客”为高阶活动.“小制作”为初阶向中阶进阶做技术准备,“小实验”为中阶向高阶进阶做方法准备.初阶活动要求学生人人参与,中阶活动要求爱好者参与,高阶活动要求有创新成果者参与,在整个活动参与过程中,学生实现了融物理于生活实践、融物理于技术实践、融物理于跨学科实践、融物理于社会实践等融合式学习和实践,让一大批科技创新型学生从进阶活动中脱颖而出. 展开更多
关键词 五小活动 进阶课程 校本探索 融物理
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冻融循环条件下重塑黄土水分迁移及其对力学性质影响 被引量:8
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作者 陈静茹 李宝平 +1 位作者 杨帆 王元戎 《科学技术与工程》 北大核心 2018年第34期226-230,共5页
以西安地区黄土为研究对象,通过常规三轴剪切试验,研究了冻融循环对重塑黄土物理力学性质的影响。结果表明:试样冻融过程中水分不断向冰晶冰冻锋面迁移;即试样冻结过程中水分向试样表面迁移,融化之后水分向试样内部迁移;在此过程中试样... 以西安地区黄土为研究对象,通过常规三轴剪切试验,研究了冻融循环对重塑黄土物理力学性质的影响。结果表明:试样冻融过程中水分不断向冰晶冰冻锋面迁移;即试样冻结过程中水分向试样表面迁移,融化之后水分向试样内部迁移;在此过程中试样结构性破坏,内部空隙增大,其剪切强度逐渐减小;故而试样含水率越大,冻融过程中水分迁移量越大,试样破坏越明显,其剪切强度降低越明显。 展开更多
关键词 循环 常规三轴试验 黄土物理性质 抗剪强度
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Vapor pressure measurement of lead and lead chlorides in FeO_T-CaO-SiO_2-Al_2O_3 system 被引量:1
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作者 张延玲 Eiki KASAI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第8期2772-2780,共9页
Vapor pressure of lead and lead chlorides from FeOT?CaO?SiO2?Al2O3 slag system was measured by using Knudsen effusion method. The results suggest that the vapor pressures of lead and lead chlorides increase with in... Vapor pressure of lead and lead chlorides from FeOT?CaO?SiO2?Al2O3 slag system was measured by using Knudsen effusion method. The results suggest that the vapor pressures of lead and lead chlorides increase with increasing temperature. For the slag systems without chlorine, the logarithm of vapor pressure (lnp) shows highly linear dependency on the reciprocal of temperature (1/T), and higher vapor pressure is observed in the condition where more metallic lead vapor is formed. In this case, the vapor pressure of lead increases with increasing slag basicity (w(CaO)/w(SiO2)), increasing FeO content andw(Fe2+)/w(Fe3+) ratio. For the case of slag system with chlorine addition, the total pressures of PbCl2 and PbCl increase with decreasing basicity and FeO content of slag. 展开更多
关键词 金属Pb vapor pressure Knudsen effusion method metallic Pb lead chlorides smelting process
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Frictional ignition of Ti40 fireproof titanium alloys for aero-engine in oxygen-containing media 被引量:7
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作者 弭光宝 黄旭 +2 位作者 曹京霞 曹春晓 黄秀松 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第8期2270-2275,共6页
The effect of friction pressure p and oxygen concentration xo on the fireproof performance of Ti40 titanium alloy was studied by frictional ignition test, the U--Xo relationship quantitatively describing the fireproof... The effect of friction pressure p and oxygen concentration xo on the fireproof performance of Ti40 titanium alloy was studied by frictional ignition test, the U--Xo relationship quantitatively describing the fireproof performance of Ti40 was established and the fireproof mechanism of Ti40 was analyzed by SEM, XRD and EDS. The results show that the p--xo relationship of Ti40 obeys parabolic rule. The varying range of xo is about 25% while p varies within 0.1-0.25 MPa. When Xo is 〉70%, Ti40 is ignited immediately at room temperature and develops into continual and steady burning, and the duration of burning is more than 10 s. The fireproof performance of Ti40 is better than TC4 while xo of Ti40 is at least 40% higher than TC4. When Xo is low, the fireproof performance of Ti40 is more sensitive to p; when Xo increases, it is more sensitive to Xo. The forming of fused oxides of V205, TiO2 and Cr203 with strong inner interaction during friction is the basic reason of high fireproof performance of Ti40. 展开更多
关键词 Ti40 fireproof titanium alloys fireproof performance fused oxides fireproof mechanism titanium fire
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三种方法构建去细胞肌肉生物支架:组织学和生物力学比较
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作者 魏祥科 文益民 +1 位作者 张涛 李含 《中国组织工程研究》 CAS CSCD 2013年第3期465-471,共7页
背景:目前构建去细胞肌肉生物支架的方法有化学方法、物理冻融法和冷冻法。目的:比较化学方法、物理冻融法和改良化学方法构建去细胞肌肉生物支架组织学和生物力学差异。方法:将6只SD大鼠竖脊肌截成36段,随机分3组(n=12),分别采用化学... 背景:目前构建去细胞肌肉生物支架的方法有化学方法、物理冻融法和冷冻法。目的:比较化学方法、物理冻融法和改良化学方法构建去细胞肌肉生物支架组织学和生物力学差异。方法:将6只SD大鼠竖脊肌截成36段,随机分3组(n=12),分别采用化学方法、物理冻融方法、改良化学方法构建去细胞肌肉生物支架。将荧光标记的骨髓间充质干细胞接种于3组支架上进行组织学与生物力学检测。结果与结论:苏木精-伊红染色显示3组支架均可见平行排列结构,化学方法组连续性较物理冻融组、改良化学组差;Masson染色显示3组支架结构主要为胶原纤维,物理冻融组残留一些肌纤维,间隙不均。物理冻融组第7天荧光标记种子细胞计数明显少于化学方法组、改良化学组(P<0.01),第14天物理冻融组少于改良化学组(P<0.05);扫描电镜可见细胞贴附各组支架生长、大量存活;物理冻融组最大载荷高于化学方法组(P<0.05),与改良化学组无明显差别,各组弹性模量无差异;物理冻融组孔隙率低于化学方法组、改良化学组(P<0.05)。表明改良化学方法可以兼顾支架的组织学和生物力学特性,彻底清除肌细胞,较多保留更完整的细胞外基质。 展开更多
关键词 生物材料 材料力学及表面改性 去细胞肌肉生物支架 骨髓间充质干细胞 化学方法 支架构建 组织学 生物力学 物理 其他基金 生物材料图片文章
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物理-化学综合融雪除冰沥青混合料研究 被引量:8
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作者 肖劲松 邹孟秋 《公路》 北大核心 2017年第8期248-252,共5页
为将橡胶颗粒沥青混合料除冰技术与盐化物融雪沥青混合料除冰技术相结合,旨在研究一种新型的环保型物理-化学融雪除冰沥青混合料。本文分别就盐化物融雪剂的选择、橡胶颗粒的掺入方法、物理-化学融雪除冰沥青混合料配合比设计、物理-化... 为将橡胶颗粒沥青混合料除冰技术与盐化物融雪沥青混合料除冰技术相结合,旨在研究一种新型的环保型物理-化学融雪除冰沥青混合料。本文分别就盐化物融雪剂的选择、橡胶颗粒的掺入方法、物理-化学融雪除冰沥青混合料配合比设计、物理-化学融雪除冰沥青混合料的成型工艺等4个方面进行了深入研究,评价了PCAM-13的融雪除冰性能,为解决冬季道路冰雪问题提供了新的思路和途径。 展开更多
关键词 雪剂 物理-化学雪除冰 橡胶颗粒 沥青混合料
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Effects of Freeze–thaw Cycles on Soil Mechanical and Physical Properties in the Qinghai–Tibet Plateau 被引量:34
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作者 XIE Sheng-bo QU Jian-jun +2 位作者 LAI Yuan-ming ZHOU Zhi-wei XU Xiang-tian 《Journal of Mountain Science》 SCIE CSCD 2015年第4期999-1009,共11页
Extreme freeze-thaw action occurs on the Qinghai-Tibet Plateau due to its unique climate resulting from high elevation and cold temperature.This action causes damage to the surface soil structure, as soil erosion in t... Extreme freeze-thaw action occurs on the Qinghai-Tibet Plateau due to its unique climate resulting from high elevation and cold temperature.This action causes damage to the surface soil structure, as soil erosion in the Qinghai-Tibet Plateau is dominated by freeze-thaw erosion.In this research,freezing–thawing process of the soil samples collected from the Qinghai–Tibet Plateau was carried out by laboratory experiments to determinate the volume variation of soil as well as physical and mechanical properties, such as porosity, granularity and uniaxial compressive strength, after the soil experiences various freeze–thaw cycles.Results show that cohesion and uniaxial compressive strength decreased as the volume and porosity of the soil increased after experiencing various freeze–thaw cycles, especially in the first six freeze–thaw cycles.Consequently, the physical and mechanical properties of the soil were altered.However, granularity and internal friction angle did not vary significantly with an increase in the freeze–thaw cycle.The structural damage among soil particles due to frozen water expansion was the major cause of changes in soil mechanical behavior in the Qinghai–Tibet Plateau. 展开更多
关键词 Qinghai Tibet Plateau Soil erosion Freeze thaw action Mechanical behavior
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Temporal consistency maintenance on multiprocessor platforms with instance skipping
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作者 BAI Tian LI Zhi-jie FAN Bo 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第11期3364-3374,共11页
Maintaining temporal consistency of real-time data is important for cyber-physical systems.Most of the previous studies focus on uniprocessor systems.In this paper,the problem of temporal consistency maintenance on mu... Maintaining temporal consistency of real-time data is important for cyber-physical systems.Most of the previous studies focus on uniprocessor systems.In this paper,the problem of temporal consistency maintenance on multiprocessor platforms with instance skipping was formulated based on the(m,k)-constrained model.A partitioned scheduling method SC-AD was proposed to solve the problem.SC-AD uses a derived sufficient schedulability condition to calculate the initial value of m for each sensor transaction.It then partitions the transactions among the processors in a balanced way.To further reduce the average relative invalid time of real-time data,SC-AD judiciously increases the values of m for transactions assigned to each processor.Experiment results show that SC-AD outperforms the baseline methods in terms of the average relative invalid time and the average valid ratio under different system workloads. 展开更多
关键词 cyber-physical systems sensor transactions multiprocessor scheduling temporal consistency
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The development trend of paper-based media under the media convergence trend
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作者 XinYu LI 《International Journal of Technology Management》 2015年第4期82-84,共3页
The emergence of media convergence have so huge impact on paper-based media that paper-based media no longer has a monopoly. Some people assert that paper-based media will come to an end. However, the author believes ... The emergence of media convergence have so huge impact on paper-based media that paper-based media no longer has a monopoly. Some people assert that paper-based media will come to an end. However, the author believes that the paper media will not come to an end under the media convergence trend. It will develop parallel with media integration. The reason why the author has this view is that, on one hand, paper-based media has its unique physical characteristics. In the real world, paper media brought us the aesthetic experience by "five senses" . It cannot be replaced by the media convergence. The paper media will also make survival steering dimension; on the other hand, cultural heritage of the paper media make itself a unique appreciation of the value and not transcendent. Therefore, the paper media in the media convergence trend will continue to exist and turned to be "concept book" that admiring is the main part and reading supplemented. 展开更多
关键词 media integration paper media five senses dimension aesthetic experience
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