手持技术数字化实验支持下的“盖斯定律”认知*

在“多重转化、比较建构”认知模型指导下,利用手持技术数字化实验和改进装置,在中学化学教材中“中和热的测定”实验的基础上进行拓展设计,用温度传感器测量3个变化过程的反应热:强碱固体溶解于水、强碱固体与稀盐酸反应以及强碱溶液与稀盐酸反应,并基于“四重表征”理论进行分析,实现对“盖斯定律”的验证,促进对“盖斯定律”的内涵认知。克服了操作烦琐、可视性不佳、实验误差大等问题,有助于在教学中渗透化学核心素养。本研究是对教材内容的补充和拓展,为教师进行“盖斯定律”教学实践提供一定参考。     

发展生物安全材料学,筑牢中国国家安全城墙

生物安全问题已经成为全世界面临的重大生存和发展威胁之一。 在当前我国常态化抗击新型冠状病毒肺炎(COVID-19)疫情的背景下,生物安全的战略地位不断提升,它不仅是对国家安全体系组成元素的不断丰富,而且也将增强我国应对突发公共卫生事件的能力,更是保障国家生物安全的必然选择。 然而,骤然爆发的COVID-19疫情,揭示了世界各国生物安全还存在漏洞。 我国疫情初期,抗疫一线防护装备严重缺乏,检测、监控手段薄弱等,其部分原因是我国生物安全相关的材料研发有所欠缺。 利用新材料来防范生物安全威胁和应对生物安全风险因子,发展生物安全材料学,加强生物安全材料学科建设及人才培养,促进生物安全材料学的发展,具有重大意义。 生物安全材料学的发展,必将满足人民健康、国家战略和国防需求,为我国国家安全提供保障。     

An Adjacency Criterion for the Prime Graph of a Finite Simple Group

For every finite non-Abelian simple group, we give an exhaustive arithmetic criterion for adjacency of vertices in a prime graph of the group. For the prime graph of every finite simple group, this criterion is used to determine an independent set with a maximal number of vertices and an independent set with a maximal number of vertices containing 2, and to define orders on these sets; the information obtained is collected in tables. We consider several applications of these results to various problems in finite group theory, in particular, to the recognition-by-spectra problem for finite groups. Supported by RFBR grant No. 05-01-00797; by the Council for Grants (under RF President) and State Aid of Fundamental Science Schools, project NSh-2069.2003.1; by the RF Ministry of Education Developmental Program for Scientific Potential of the Higher School of Learning, project No. 8294; by FP “Universities of Russia,” grant No. UR.04.01.202; and by Presidium SB RAS grant No. 86-197. __________ Translated from Algebra i Logika, Vol. 44, No. 6, pp. 682–725, November–December, 2005.     

Almost simple groups with socle ~3D_4(q) act on finite linear spaces

After the classification of flag-transitive linear spaces, attention has now turned to line-transitive linear spaces. Such spaces are first divided into the point-imprimitive and the point-primitive, the first class is usually easy by the theorem of Delandtsheer and Doyen. The primitive ones are now subdivided, according to the O'Nan-Scotte theorem and some further work by Camina, into the socles which are an elementary abelian or non-abelian simple. In this paper, we consider the latter. Namely, T≤G≤Aut(T) and G acts line-transitively on finite linear spaces, where T is a non-abelian simple. We obtain some useful lemmas. In particular, we prove that when T is isomorphic to 3D4(q), then T is line-transitive, where q is a power of the prime p.     

用调频正弦波形和示波器同步原理模拟纵波

基于示波器同步原理,用固定周期的调制电信号模拟机械简谐振动源,用调频波形模拟质点的稠密区和稀疏区,用不同步的左右移动波形模拟质点作简谐振动,实现了在示波器上模拟纵波.     

市政给水排水管道工程的工程报验

通过乌鲁木齐市外环路给水排水管道工程实例，谈谈给水排水管道工程在施工过程中工程报验应有的内容、采用的形式和控制指标。     

有限Diophantine逼近与Fibonacci多项式

设x为一无理数具简单的连分式展开x = [a0, a1, a2,…, an].若对无穷多个是标k有ak> n则至少有m个解p/q(p与q互素)使不等式 x - p/q 相似文献   

基于遗传算法的同步优化算法

提出一种基于遗传算法的同步优化算法,该算法吸取了遗传算法和模拟退火算法的各自优点,将二进制编码和实数编码有机地结合起来,既能够快速收敛到全局最优解,又能够在优化神经网络结构的同时,得到较好的权值分布.     

《线性代数》内容的关联性研究

《线性代数》学科知识点关联性强、相互交叉相互引证的情况比较多.清晰把握知识点之间的关系成为有效教学的重要前提.本文通过建构知识点关联层次图,试图理顺知识点关系、把握好内容格局,并结合教学经验提出一种教学时序.