苯乙烯/甲基丙烯酸3-氯-2-羟基丙酯共聚物的合成与表征   总被引：1，自引：0，他引：1  

袁焜  李志锋  吕玲玲 《天水师范学院学报》2006,26(5):10-12

制备了甲基丙烯酸-3-氯-2-羟基丙酯(CHPMA),采用自由基悬浮聚合的方法,使其与苯乙烯进行共聚合,首次合成了苯乙烯/-а甲基丙烯酸-3-氯-2-羟基丙酯线型无规共聚物,并用FT-IR和GPC对共聚产物进行了表征,讨论了聚合条件对产物收率的影响。结果显示该共聚物的数均分子量达到10万以上,其分子量多分散系数为1.72,有望用于极性橡胶(如氯丁橡胶等)与亲水性树脂(如聚丙烯酸、聚丙烯酰胺等)共混的增容剂以制备稳定性良好的特种功能材料——吸水膨胀橡胶。  相似文献   

21世纪初我国高校体育师资队伍建设分析   总被引：35，自引：0，他引：35  

廖祥龙  高加良 《体育学刊》2002,9(1):95-96,99

分析我国高校体育教师队伍现状和存在问题，并结合知识经济的理论和本人从事10多年高校体育教学工作的实际，探讨新世纪初提高我国高校体育师资队伍整体素质的基本思路和主要措施。  相似文献   

N,N-双(2-羟基-3-磺酸基丙基)氨基乙酸(BHSPA)的合成研究   总被引：2，自引：0，他引：2  

曹展梅 《扬州教育学院学报》2004,22(3):45-47

以甘氨酸、环氧氯丙烷、饱和NaHSO3溶液为主要原料,合成了分子中含有羟基、羧基、磺酸基等多个官能团的产物BHSPA。其水溶性好,阻垢、缓蚀性能强,系一种低氮、无磷的新型水处理剂。用元素分析,红外光谱,核磁共振等手段对产物进行结构鉴定,证明与预期的结果一致。  相似文献   

Facile and efficient one-pot synthesis of 2-arylbenzoxazoles using hydrogen tetrachloroaurate as catalyst under oxygen atmosphere     

Yun-kui Liu  Da-jie Mao  Shao-jie Lou  Jian-qiang Qian  Zhen-yuan Xu 《Journal of Zhejiang University. Science. B》2009,10(6):472-478

In this paper, we presented a novel method for the facile and efficient one-pot synthesis of 2-arylbenzoxazoles, which oxygen atmosphere with anhydrous tetrahydrofuran (THF) as solvent or in solvent-free condition. The results show that this method could bring excellent yields as high as 96%. THF was proven to be the best choice among several solvents screened and the reaction was tolerated with a variety of aromatic aldehydes possessing electron-donating or withdrawing groups. The advantages of the present method lie in catalytic process using economic and environmentally benign dioxygen as oxidant.  相似文献   

运用模糊综合评价法评价体育新课标下学生的学习   总被引：1，自引：0，他引：1  

丁曙 《安徽体育科技》2008,29(1):76-79

通过对学生学习评价指标体系的建立，确定评价的等级和隶属度，采用专家评判平均法确立各项指标的权重。运用模糊综合评价法对学生的学习进行评价，旨在找到一种能体现新课标理念的、科学的、易探作的评价方法，更好地为素质教育服务。  相似文献   

有氧运动条件下一氧化氮合成与肝脏尿素循环之间关系初探   总被引：2，自引：0，他引：2  

王冰梅  徐朝晖 《体育科学》2005,25(5):47-49

以方差分析和线性相关分析方法，探讨补充精氨酸和游泳训练对小鼠血NO(bNO)、血尿素氮(bBUN)和骨骼肌一氧化氮合酶(sNOS)的影响，篮球训练对大学生bNO、bBUN的影响以及小鼠／人肝脏尿素生成与NO合成之间的关系。结果表明：1)补充精氨酸对安静和训练小鼠NO和尿素生成均无显著影响；2)有氧训练使人／小鼠的NO和尿素生成均显著增加，且两者呈高度相关。结论：机体通过有效的自身调节机制，能够满足有氧运动下NO和尿素合成对Arg的需求，不需额外补充；肝脏尿素循环与外周NO合成是相互促进的，这也许是机体在有氧运动条件下对Arg、Cit需求与供应的自身调节机制，即：同肝脏与骨骼肌之间的葡萄糖—丙氨酸循环一样，肝脏与外周NO合成组织间可能存在着高效的“Cit—Arg cycle”。该结论需进一步实验证实。  相似文献   

High school boys’ and girls’ writing conceptions and writing self-efficacy beliefs: what is their role in writing performance?     

Ruth Villalón  Mar Mateos  Isabel Cuevas 《教育心理学》2015,35(6):653-674

This study investigated the conceptions about writing and writing self-efficacy beliefs held by high school students in relation to the students’ gender as well as their associations with writing achievement. The results show that female students have more sophisticated writing conceptions than their male counterparts but no gender differences were found in writing self-efficacy beliefs. In addition, results reveal that writing self-efficacy beliefs and gender play an important role in predicting writing performance and that writing performance is moderated by students’ writing conceptions. Educational implications and further research are discussed.  相似文献   

溴硝基丙二醇的合成和防腐活性研究     

肖剑国 《邵阳学院学报(社会科学版)》2001,23(2):49-50

合成了防腐剂2-溴-2-硝基-1,3-丙二醇,通过IR波谱和元素分析对其进行表征,并对其防腐性能和毒性研究.  相似文献   

Mobile APP for motivation to learning: an engineering case     

Min Jou  Yen-Ting Lin  Hsieh-Chih Tsai 《Interactive Learning Environments》2016,24(8):2048-2057

Synthesis of Materials is regarded as an important core subject in engineering education. However, many concepts and knowledge in the material synthesis can be rather abstract and difficult to understand by the student learners. Experiments are limited in scope due to lack of equipment, control of toxic materials, and risks of chemical reactions, which often restricts student imagination and student involvement in practical training. These reasons often led to poor learning attitude and learning performance among the students. Rapid developments in Cloud technology and mobile devices have provided new opportunities for developing novel learning tools for material synthesis. This study aims to introduce interest factors as a strategy for promoting learning interest and practical skills among the students. Chemical symbols, experimental themes, texts, and interactive elements were utilized to develop a theme-based Mobile Learning APP for teaching the practical techniques of material synthesis. The Mobile Learning APP was then integrated into a problem-based learning activity. A quasi-experimental design was used to investigate the resulting learning effectiveness from using the developed Mobile Learning APP. Results show that the Mobile Learning APP provided a significant positive effect on learning performance and that most students showed favorable attitudes toward the usage of the mobile learning system.  相似文献   

中国传统思维方式的特征及形成原因   总被引：2，自引：0，他引：2  

代杰 《哈尔滨学院学报》2004,25(8):42-46

中国传统思维方式是指那些在中华民族发展过程中 ,“长久地、稳定地起作用的思维习惯、思维方法” ,以及“对待事物的审视趋向和公认的观点”。它是一种东方的智慧 ,意蕴相当丰富 ,既有历史的智慧积淀 ,又有现实的智慧映像 ,还有未来智慧的闪光。中国传统思维方式正是在其特定条件下形成的 ,它的特征在世界上更是独一无二的。因此 ,只有对中国传统思维方式重新加以认识 ,我们才能真正成为东方智慧的发扬者。  相似文献