Classroom     

Praveen Pathak  Vijay A. Singh  Homi Bhabha  Himanshu Asnani 《Resonance》2007,12(6):58-66

In this section of Resonance, we invite readers to pose questions likely to be raised in a classroom situation. Wemay suggest strategies for dealingwith them, or invite responses, or both. “Classroom” is equally a forum for raising broader issues and sharing personal experiences and viewpoints on matters related to teaching and learning science.  相似文献   

University physics students’ ideas of thermal radiation expressed in open laboratory activities using infrared cameras     

Jesper Haglund  Emil Melander  Matthias Weiszflog  Staffan Andersson 《Research in Science & Technological Education》2017,35(3):349-367

Background: University physics students were engaged in open-ended thermodynamics laboratory activities with a focus on understanding a chosen phenomenon or the principle of laboratory apparatus, such as thermal radiation and a heat pump. Students had access to handheld infrared (IR) cameras for their investigations.

Purpose: The purpose of the research was to explore students’ interactions with reformed thermodynamics laboratory activities. It was guided by the research question: How do university physics students make use of IR cameras in open-ended investigation of thermal radiation as a phenomenon?

Sample: The study was conducted with a class of first-year university physics students in Sweden. The interaction with the activities of four of the students was selected for analysis. The four students are males.

Design and methods: We used a qualitative, interpretive approach to the study of students’ interaction. The primary means of data collection was video recording of students’ work with the laboratory activities and their subsequent presentations. The analysis focused on how IR cameras helped students notice phenomena relating to thermal radiation, with comparison to previous research on students’ conceptions of thermal radiation.

Results: When using the IR camera, students attended to the reflection of thermal radiation on shiny surfaces, such as polished metals, windows or a whiteboard and emissive properties of surfaces of different types. In this way, they went beyond using the technology as a temperature probe. Students were able to discuss merits and shortcomings of IR cameras in comparison with digital thermometers.

Conclusions: With the help of IR cameras, university physics students attend to thermal phenomena that would otherwise easily go unnoticed.  相似文献   

Effect of Air Velocity on Thermal Comfort under Thermal Environment Ramp Changing   总被引：1，自引：0，他引：1  

嵇赟喆  涂光备  孙琳 《天津大学学报(英文版)》2004,10(4):291-296

Set points of the indoor air temperature and relative humidity in short-term staying location were studied. In this condition, the thermal reaction of human body varied with the ramp changes of the environmental thermal parameters. The change rules of about 60 subjects‘ thermal reaction to the ramp change of environment were surveyed, and the effect of air movement on the thermal reaction during transient condition was considered by using a questionnaire. With the experimental results and research findings under stable condition, a way to set environmental parameters of short-time staying location was recommended.  相似文献   

抗冻蛋白的抗冻活性及其测定方法   总被引：1，自引：0，他引：1  

邵强  李海峰  刘国生  闫清华 《平原大学学报》2005,22(4):111-113

抗冻蛋白是一类能够保护生物体免受结冰引起伤害的蛋白质，其抗冻活性表现为热滞性和重结晶抑制效应。本文讨论了影响抗冻蛋白活性的因素，介绍了抗冻蛋白热滞活性和重结晶抑制效应的定量测定方法。  相似文献   

羟基磷灰石的微波快速烧结研究   总被引：5，自引：0，他引：5  

蔡杰  徐耕夫  李文兰  庄汉锐  郭景坤 《中国科学院研究生院学报》1996,(2)

羟基磷灰石与脊椎动物的牙齿和骨骼组织的组成极为相似，研究表明它与这些生理组织具有良好的亲合性．羟基磷灰石作为牙齿和骨骼移植材料的研究越来越受到重视．利用自行研制的微波烧结系统对羟基磷灰石进行烧结研究．经过１０００～１０５０℃保温２分钟的微波烧结可以获得超微结构（平均晶粒尺寸为３００纳米），密度大于９８％ＴＤ（理论密度）的羟基磷灰石．同时还对微波烧结过程中的加热特征及热失控的作用展开了讨论．  相似文献   

实验室快速制作印制电路板后处理工艺研究     

石万里 《实验技术与管理》2011,28(6):47-48,56

印制电路板(printed circuit board,PCB)是电子设备内部电子元件的主要载体。PCB设计和加工工艺是高校电子类专业学生必须掌握的专业技能,但是专业工厂批量加工PCB的工艺并不适合在高校实验室使用。给出了一种适合在校学生快速制作PCB的工艺路线,重点解决了"一图一板"加工中绿油阻焊膜和元器件标志快速印制的难题。  相似文献   

常用冷库结构性能分析     

薛梅  王爱芹  李树林  晁风芹 《山东商业职业技术学院学报》2011,11(3):89-93

针对常用的冷库结构,从维护结构的传热量、蒸汽渗透率以及冷库投资运行费用等方面进行分析比较,从而找出低造价、高性能、低能耗的库体结构。  相似文献   

EPS外墙外保温系统抗裂研究     

陈翠琼 《武汉职业技术学院学报》2011,10(3):86-89

对EPS外墙外保温系统的面层开裂原因进行分析,主要从构造设计、材料及施工三方面研究裂缝预防方法。  相似文献   

山西省温泉旅游资源研究   总被引：1，自引：0，他引：1  

程远曲 《晋城职业技术学院学报》2011,4(1):58-60

山西独特的地理位置形成了丰富的温泉资源,借助温泉资源大力发展温泉休闲度假旅游,是山西旅游业发展的需要。本文对山西各地温泉资源的分布、地质、分类、旅游价值、开发历史及现状等问题进行了调查,提出了一些建议,以期对山西温泉资源开发利用有所借鉴。  相似文献   

基于ANSYS的Au-Al引线键合热可靠性研究     

成磊 《晋城职业技术学院学报》2011,4(2):39-43

采用ANSYS有限元分析软件建立Au-Al引线键合模型考察键合区在热循环加载下的应力应变情况;并采用Coffin-Manson方程计算了在热循环加载下焊点的疲劳寿命。结果表明：随着热加载循环次数的增加,模型的应力应变将增大;施加约束后,模型的应力将减小,引线键合的寿命延长。此方法可以比较各种不同情形下Au-Al引线键合热可靠性。  相似文献