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41.
采用磁控溅射方法在Si片沉积了Ti-50.9at%Ni形状记忆合金薄膜,并将薄膜分别在不同温度下进行退火.利用示差扫描量热方法(DSC)、X射线衍射仪(XRD)、透射电镜(TEM)研究了薄膜退火前后形貌、相变特征及应力随退火温度的变化.实验结果表明:溅射态薄膜为非晶态,其晶化温度范围为430℃-535℃,晶化同时伴随着Ti3Ni4相的析出;退火后的薄膜随着退火温度的升高,Rs、Af、Ms均呈上升趋势.薄膜的残余应力随着退火温度的增加而逐渐减少. 相似文献
42.
研究了不同浓度的钠盐(Na2SO4和Na2CO3)胁迫对红麻种子萌发和幼苗生长的影响.结果表明:不同浓度盐胁迫对红麻种子的发芽指标和活力指数均有一定抑制作用,随浓度的增加抑制作用越强.浓度10~50 mmol/L的Na2SO4胁迫下,红麻种子的发芽势、发芽指数与对照没有显著差异,但活力指数显著低于对照,而当Na2SO4浓度为100 mmol/L时种子的发芽势、发芽指数与对照存在显著差异,Na2SO4浓度为200 mmol/L时种子不能萌发;Na2CO3浓度≥50 mmol/L时,红麻种子不能萌发.相同浓度下,Na2CO3比Na2SO4对红麻种子萌发的抑制作用更明显. 相似文献
43.
研究了NaCl胁迫对5个不同番茄品种的幼苗生长、果实可溶性糖含量及产量的影响.结果表明,盐胁迫抑制了番茄幼苗植株的生长,降低了幼苗的单株鲜重,减少了果实产量,但可以提高果实可溶性糖含量.同一盐胁迫条件下,不同番茄品种性状存在显著差异. 相似文献
44.
本文介绍了精神创伤的EMDR(眼动脱敏与再加工)治疗过程中的八个步骤,以及每个步骤中值得注意的问题。 相似文献
45.
Michelle Rowbotham Monica Cuskelly 《International Journal of Disability, Development & Education》2011,58(3):223-240
To date, there have been few studies of mothers’ and fathers’ roles in caring for their adult children with intellectual disabilities. The present study investigated the care-giving roles of mother and father couples caring for their adult offspring with an intellectual disability, their psychological health, and the demands and satisfaction of their care-giving roles. Twelve Anglo-Australian middle-aged mother and father couples with an adult child with intellectual disability (mean age?=?24 years) participated in semi-structured interviews about their care-giving roles and completed a series of questionnaires pertaining to care-giving difficulties and satisfaction, hassles and uplifts, and general health. Findings indicated that an extremely high proportion of both mothers and fathers were in the clinical range for social dysfunction, anxiety/insomnia, and somatic complaints, although levels of depression were relatively low. The present study found that mothers undertake more daily care-giving tasks than fathers, but that the range of tasks is similar. Mothers also reported significantly more care-giving difficulties and satisfaction than fathers. Associations between measures differed somewhat for the two parent groups, indicating the need for further exploration of both mothers’ and fathers’ experiences. 相似文献
46.
Simkin P 《The Journal of perinatal education》2011,20(3):166-176
In this column, Kimmelin Hull, community manager of Science & Sensibility, Lamaze International's research blog, reprints and discusses a recent blog post series by acclaimed writer, lecturer, doula, and normal birth advocate Penny Simkin. Examined here is the fruitful dialog that ensued-including testimonies from blog readers about their own experiences with traumatic birth and subsequent posttraumatic stress disorder. Hull further highlights the impact traumatic birth has not only on the birthing woman but also on the labor team-including doulas and childbirth educators-and the implied need for debriefing processes for birth workers. Succinct tools for assessing a laboring woman's experience of pain versus suffering are offered by Simkin, along with Hull's added suggestions for application during the labor and birth process. 相似文献
47.
林火生 《柳州职业技术学院学报》2011,11(4):66-70
在分析户式中央空调系统热稳定性影响因素的基础上,给出了改善系统稳定性的设计措施,并结合一个别墅户式中央空调系统设计实例,从系统热稳定性的角度进行了设计分析,还指出了改善户式中央空调变频机组系统热稳定性的其他措施,为设计舒适、节能的户式中央空调系统提供参考。 相似文献
48.
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
49.
中学教师职业压力调查分析 总被引:5,自引:0,他引:5
教育学、心理学、工效学、医学等多学科的研究均发现职业压力已成为一种严重影响人的身心健康和工作、生活质量的社会流行病。教师,尤其是中学教师,由于其职业的特殊性,压力过大或过于持久,不仅会严重损害他们的身心健康,还会影响到他们的学生——青少年的健康成长。这里运用自编的中学教师职业压力问卷,对428名城市普通中学教师的职业压力现状进行了调查研究和分析。 相似文献
50.
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