The LPS concept, a new way to look at anionic conductors

A new approach to anionic conduction is presented, and illustrated using already well-known anion conductors, as well as the recently discovered fast oxide-ion conductor La₂Mo₂O₉. The so-called LPS (lone-pair substitution) concept could be used to seek for novel families of anion conductors, issued from already known compounds with lone-pair elements. It is based on the similarity in volume between an electronic lone pair and oxide or fluoride anions, and on the vacancy created by the replacement of a lone-pair by a non-lone-pair cation. A tentative list of the most appropriate substituting elements for given lone-pair cations is presented.     

GPS中的时空测量

本文从ＧＰＳ全球卫星定位系统中的时空测量及相对论效应的应用说明物理学理论在当代科学技术中起着重要的作用。     

The Gibbs' phenomenon and harmonic oscillators with periodic forcing

We present an interesting nonlinear equation originating from a geometrical problem. We show how it can be solved numerically, how algorithmic differentiation is useful, and how the problem can also be solved analytically using the computer algebra system Maple.     

结构化学课程教学中融入思政元素的探索

转变教学理念是提升教学水平的重要手段,是促进教学改革的有力途径。结合近些年来社区和学校对垃圾分类的宣传,将生态文明的理念和垃圾分类知识点有机嵌入到课程教学中。采取教师授课引导、学生自学探究、课下实践分组讨论、总结汇报等教学方式,形成以生态文明教育理念为核心思想,电化学课程知识内容为中心轴线,垃圾分类知识点为"羽翼"的课程结构设计。主要从生态文明的重要性、教学理念转变、课程实例、考核评价等方面来论述。     

基于模型建构的论证教学在化学概念学习中的应用*——以“原电池”概念学习为例

基于呈现批判反思提炼(PCRR)模式,提出了假设呈现批判反思提炼(HPCRR)模式,并以“原电池”概念学习为例,进行教学设计与教学实施。研究对象为广东省佛山市某校高二年级2个平行班的92名学生,其中实验组和对照组均为46人。从概念理解和学生对该教学模式的态度等2个方面调查了实施效果。结果显示,教学干预后,实验组学生的概念理解明显优于对照组,表明该教学模式能有效促进学生的概念理解,实现概念转变。实验组学生对该教学模式的接受度较高,持积极态度。     

GENERALIZED Ⅰ-NONEXPANSIVE MAPS AND INVARIANT APPROXIMATION RESULTS IN p-NORMED SPACES

We extend the concept of R-subcommuting maps due to Shahzad[17,18] to the case of non-starshaped domain and obtain a common fixed point result for this class of maps on non-starshaped domain in the setup of p-normed spaces. As applications, we establish noncommutative versions of various best approximation results for generalized I-nonexpansive maps on non-starshaped domain. Our results unify and extend that of Al-Thagafi, Dotson, Habiniak, Jungck and Sessa, Latif, Sahab, Khan and Sessa and Shahzad.     

Inclusion Size Distribution and Endurance Limit of a Hard Steel

High cycle fatigue failure of hard steels is dominated by a long crack initiation phase and a short crack propagation phase. The crack initiation sites are inclusions or surface defects. Due to this, the endurace probability of a hard steel part depends on its crack initiating inclusion size or surface defect size distribution. These consideration lead to the weakest-link concept which allows to calculate local and total endurance probabilities of the cycled parts. From these probabilities, the endurance limit and the probable crack initiation sites can be predicted. Base of the prediction is the knowledge of the endurance limits under three different load conditions. From these data and fracture-mechanic relations for the different inclusion types, the distributions of the crack initiating inclusion sizes can be predicted.     

电负性研究(Ⅱ)—氢的电负性

氢的电负性值是氢元素性质的重要参数，１９３２年Pauling犤１～３犦定量确定氢的相对电负性值等于２．１，１９６１年Allred犤４，５犦用更准确的实验数据对Paul－ing电负性标度进行了修正，氢的电负性值被确定为２．２，目前这两个数值都在采用。元素的电负性值是与元素的性质紧密相关的，一个合适的电负性标度应该至少反映所有重要元素的电负性值，氢的化合物比任何其它元素都多，理应有一个基本的准确电负性值，然而一些电负性标度中却缺乏这样的数据。在Murphy等四人犤６犦最近发表的论文中，对Pauling电负性标度又进行了深入考查与…     

Partially nanowire-structured TiO2 electrode for dye-sensitized solar cells

Partially nanowire-structured TiO₂ was prepared by a hydrothermal processing followed by calcination in air. The hydrogen titanate powder as-synthesized was calcined at 300 °C for 4 h to obtain the partially nanowire-structured TiO₂. A dye-sensitized solar cell (DSC) with a film thickness of 5.6 μm, fabricated using the partially nanowire-structured TiO₂ showed better performance than using a fully nanowire-structured TiO₂ or a conventional equi-axed TiO₂ nanopowder. The short-circuit current density (J_SC), the open-circuit voltage (V_OC), the fill factor (FF) and the overall efficiency (η) are 11.9 mA/cm², 0.754 V, 0.673 and 6.01 %, respectively. The effects of one-dimensional nanostructure and electron expressway concept are discussed.     

The LDC detector concept

In preparation of the experimental program at the international linear collider (ILC), the large detector concept (LDC) is being developed. The main points of the LDC are a large volume gaseous tracking system, combined with high precision vertex detector and an extremely granular calorimeter. The main design force behind the LDC is the particle flow concept. for the LDC Concept Group