Achieving ultrahigh electrochemical performance by surface design and nanoconfined water manipulation

The effects of nanoconfined water and the charge storage mechanism are crucial to achieving the ultrahigh electrochemical performance of two-dimensional transition metal carbides (MXenes). We propose a facile method to manipulate nanoconfined water through surface chemistry modification. By introducing oxygen and nitrogen surface groups, more active sites were created for Ti₃C₂ MXene, and the interlayer spacing was significantly increased by accommodating three-layer nanoconfined water. Exceptionally high capacitance of 550 F g^–1 (2000 F cm^–3) was obtained with outstanding high-rate performance. The atomic scale elucidation of the layer-dependent properties of nanoconfined water and pseudocapacitive charge storage was deeply probed through a combination of ‘computational and experimental microscopy’. We believe that an understanding of, and a manipulation strategy for, nanoconfined water will shed light on ways to improve the electrochemical performance of MXene and other two-dimensional materials.     

学习、知识能量、核心能力如何提升绩效——华南地区企业的实证研究

探讨学习、知识能量及核心能力如何提升组织的绩效,并以华南地区的157家企业为对象进行实证研究.结果表明,以学习为导向的组织必须通过知识能量的积累才能促进核心能力的提升并最终提高组织的绩效;知识能量的积累并不能直接带来组织绩效的改善,而需通过核心能力的提升才能对组织绩效产生间接的正向影响.     

《中国美术史》教学改革的实践和思考

文章分析了当前高校《中国美术史》教学现状和改革的迫切性 ,总结教学改革的实践经验 ,提出改革传统教学模式 ,把美术历史教育、文化教育和爱国主义教育结合起来 ,充分利用现代教育技术 ,激发学生创新精神 ,提高学生全面素质的改革思路     

生命需要的是什么

淡泊：人间有味是清欢 美国巨星罗斯顿陨落前的警语：“你的生命需要的仅仅是一颗心脏!”时时在我耳畔回荡。然而,叹大千世界,悲恨相续,无数人依然竞相为生命背囊增重。或许,我们真的需要一个安静的夜晚,思考,生命需要的是什么？我听到一个声音传来：生命的需要,是一颗清净淡泊的心。     

师生教学信息不对称问题浅析

教师在品德、知识和能力等信息方面与学生存在不对称现象,是教师成为合格教师的基本条件。建立学习型组织、实施知识管理工程,克服信息经济环境中教师与学生正在缩小的不对称差距程度,给学校教育注入持续活力。     

密度均匀球壳的引力与引力势能

计算了密度均匀球壳内、中、外的引力场分布和引力势能,并与均匀带电球壳的电场分布和电势能作了比较.     

Investigation on wind energy-compressed air power system

Wind energy is a pollution free and renewable resource widely distributed over China. Aimed at protecting the environment and enlarging application of wind energy, a new approach to application of wind energy by using compressed air power to some extent instead of electricity put forward. This includes: explaining the working principles and characteristics of the wind energy-compressed air power system; discussing the compatibility of wind energy and compressor capacity; presenting the theoretical model and computational simulation of the system. The obtained compressor capacity vs wind power relationship in certain wind velocity range can be helpful in the designing of the wind power-compressed air system. Results of investigations on the application of high-pressure compressed air for pressure reduction led to conclusion that pressure reduction with expander is better than the throttle regulator in energy saving.     

Taking active learning into the primary school: a matter of new practices?

This paper examines the extension of active learning pedagogical practices familiar in preschool settings to the first class of primary school. Policy and practice guidance in the UK is advocating the benefits of experiential learning as a way of engaging young children as they move into primary school but for teachers this means a move to new practices which can be in tension with other expectations. In this paper, the rationale for active learning is considered along with an account of the classroom activities of teachers and children in five primary schools that were implementing the policy shift to active learning. The children in these classes spent varying amounts of time in whole class activities led by the teacher or in small groups directed to engage with specific activities. They had opportunities to engage and respond verbally, through manipulating objects and with physical actions but the emphasis was on planned, teacher-directed learning activities. The characteristics of active learning as introduced in these innovative classes are compared with the expectations of practice guidance and theorising about early learning.     

太阳能二次聚集器聚光性能研究

采用蒙特卡洛射线踪迹法,ProE和TracePro软件技术,模拟分析了多棱台与一次抛物面、复合抛物面二次聚集器与一次抛物面两级聚集器的太阳光聚集传输特性。通过对比,发现多棱台二次聚集器的几何聚光比为1.4左右(约为复合抛物面聚集器的70%)。多棱台与一次抛物面、复合抛物面二次聚集器与一次抛物面两级聚集器圆筒侧壁和底面的太阳能流密度分布图像相当(沿圆周方向,复合抛物面两级聚集器相对比较平滑)。结论为反射二次聚集器技术发展提供理论依据。     

对太阳能建筑一体化技术的思考

整合技术体现的是一种美,太阳能建筑一体化技术是基于生态建筑这一理论的.太阳能建筑一体化技术更是站在节能和环保的高度来实现对建筑技术和太阳能技术的结合,并实现整体外观和设备功能的统一,以及与周围环境的和谐一致.