对苯二酚在玻碳电极上的电化学行为及其动力学研究

研究了对苯二酚（HQ）在玻碳电极上于磷酸盐缓冲液（PBS）中的电化学行为及其电化学动力学性质。结果表明：HQ在该电极上有一对可逆的氧化还原峰,峰电流与扫描速度的平方根（v1/2）呈良好的线性关系。这说明HQ在该电极上的伏安行为是一受扩散控制的可逆电化学过程。在pH为6.08的PBS缓冲液中氧化峰电流与HQ的浓度在5.0×10^-6-2.5×10^-5 mol/L范围内呈良好的线性关系,Ipa（μA）=-1.444-0.077 8 c（μmol/L）,相关系数r=0.996 5,检测限为4.75×10^-6 mol/L。同时利用电化学方法确定了该电极反应过程是双电子转移,并测得传递系数α为0.626,扩散系数D为7.4×10-7 cm^2/s,电极反应速率常数kf为6.8×10^-4 cm/s。     

广义Ramsey数R(K_3,K_(21)-e)和(K_3,K_(22)-e)的新下界

研究了完全图的循环着色,得到了广义Ramsey数R(K3,Kq-e)的两个新下界:R(K3,K21-e)≥111、R(K3,K22-e)≥122.     

对乙酰氨基酚在铁氰化铜修饰电极上的电化学行为研究

用循环伏安法制备了铁氰化铜修饰玻碳电极,并研究了对乙酰氨基酚在该修饰电极上的电化学行为。结果表明,在pH=6.86的磷酸缓冲溶液中,对乙酰氨基酚在铁氰化铜修饰电极上0.437V处出现一氧化峰,与裸玻碳电极相比氧化峰电位负移了81mV。对乙酰氨基酚浓度在4×10-5-1×10-3mol/L范围内,其氧化峰电流与浓度呈现很好的线性关系,其相关系数是0.9993,检出限为1×10-5mol/L。     

Enhancing student teachers’ epistemological beliefs about models and conceptual understanding through a model-based inquiry process

In this study we present the structure and implementation of a model-based inquiry teaching–learning sequence (TLS) integrating expressive, experimental and exploratory modelling pedagogies in a cyclic manner, with the aim of enhancing primary education student teachers’ epistemological beliefs about the aspects, nature, purpose and change of models as well as their conceptual understanding of light phenomena related to properties of optical fibres. The subjects were 16 prospective primary teachers involved in modelling activities, employing both hands-on experiments and computer modelling activities, based on the application of the ray model. Student teachers were tested before and after the implementation of the TLS by semi-structured interviews and a written questionnaire. Results show that before the TLS most students adopted epistemologically naïve realistic beliefs about models, whereas after the TLS there was an overall significant transition from naïve to more sophisticated epistemological beliefs, as well as significant improvements in their conceptual knowledge about light phenomena. Nevertheless, the relation between epistemological beliefs and conceptual understanding seems to be aspect-dependent, so our evidence suggests that more educational effort is required in order to establish a coherent relationship between them.     

非比例循环载荷下的随动强化律

对于４２ＣｒＭｏＡ钢的非比例循环实验，讨论了几个随动强化律的适用性，其中包括Ｐｒａｇｅｒ、Ｚｉｇｌｅｒ、Ｃｈａｂｏｃｈｅ、Ｍｒｏｚ和Ｔｓｅｎｇ－Ｌｅｅ强化律。分析表明与双曲面本构模型相关的Ｍｒｏｚ和Ｔｓｅｎｇ－Ｌｅｅ强化律能给出较好的预测。文中还给出了一个简化的双曲面本构模型     

The Sacred Circle: A process pedagogy of healing

This paper proposes a process pedagogy based on an aboriginal approach to healing. It is founded on the Sacred Circle teachings of Canadian Plains Indians and on the educational practices undertaken at a school for aboriginal youth, the Joe Duquette High School in Saskatoon, Saskatchewan, Canada. Healing, is viewed here as transition toward meaning, wholeness, connectedness, and balance (Katz & St. Denis, 1991, p. 24). As aboriginal pedagogy, this approach to the practice and theory of teaching is selfconsciously founded on process symbolized in the Sacred Circle. It is presented here as part of a critical theory of education committed to human emancipation that recognizes that the appropriation of an aboriginal world view as a foundation for teaching is undertaken within the context of modern political and cultural systems and institutions that have excluded, denied, or rejected aboriginal world views. The Sacred Circle is a traditional symbolic circle that incorporates the spiritual beliefs of many Indian tribes of North America, including Dakota Nations, Blackfoot Confederacy, Cree, Saulteaux, and Assiniboine nations in Canada. It symbolizes harmony and the belief that life occurs within a series of circular movements that govern their relationship with the environment. Although the Sacred Circle has symbolized aboriginal world views for thousands of years, some schools are beginning only now to use it as a self-conscious foundation for education as healing.The paper begins with Whitehead's criticism of Western metaphysics and his notion of reality as process. These ideas and some of his views about education and teaching provide an introduction to and framework for developing the notion of healing as a process pedagogy based upon the Sacred Circle concept. The Sacred Circle is examined as the expression of an aboriginal metaphysics in which reality is conceptualized as process, the movement of life through wholeness, connectedness, and balance. Healing and teaching are viewed as the transition to meaning in that movement. Finally, process pedagogy as healing is interpreted as having the three phases of belonging, understanding, and critical reflection through an examination of practices at the Joe Duquette High School.     

LZ50车轴钢低周疲劳性能研究

研究了LZ50车轴钢的循环相关特性,循环疲劳特性及循环应力-应变关系。试验结果表明:LZ50车轴钢的循环疲劳特性曲线及循环应力-应变曲线很好地符合双对数线性关系;其循环相关特性表现为先循环软化,稳定后又发生循环硬化,而且循环软化和循环硬化的程度随控制应变的不同而不同。     

聚二茂铁硅烷膜在水溶液中的循环伏安研究

采用循环伏安法研究了聚二茂铁二甲基硅烷膜(PFDMS)和聚二茂铁甲基苯基硅烷膜(PFMPS)在8种常规电解质水溶液中的电化学行为，在一些电解质水溶液中，循环伏安峰迅速衰减，而在一些电解质水溶液中可得到稳定、重复的循环伏安谱．测定了两种膜在LiClO4水溶液中循环伏安过程的表面传递系数(ana)、表观扩散系数(Dapp)和表面电荷传递速率常数(K^0)，讨论了膜的电极过程机理．     

超微双环银电极的制作及其性能测试

章介绍了通过在玻璃毛细管内外壁化学镀银制作超微双环银电极的方法，并检测了该电极的特性。     

GIS-Based Simulation of Engineering Construction Schedule

For its complexity, engineering construction schedule design is limited by various factors. Simulation-based engineering construction schedule takes critical path method （ CPM ） network as frame and calls complex cyclic operation network （CYCLONE） simulation model enclosed in advance for its simulation nodes. CYCLONE simulation model takes charge of simulating stochastic duration of activity and efficiency of resources, while CPM model performs project scheduling. This combination avoids the shortcomings of both models. Furthermore. geographic information system （ GIS ） technique is utilized to visualize the construction processes which are otherwise difficult to be understood by static results described. Application in practical project verifies the feasibility and advantage of the technique.