国际核机制在冷战后的发展状况研究

国际核机制的建立旨在规范利用核技术行为,保障整个人类的安全。冷战结束以来,国际环境发生了重大变化。一方面国际核机制面临着种种挑战,但另一方面冷战后的国际形势也为其提供了良好的发展机遇。各国要抓住机遇,应对挑战,继续为完善国际核机制而努力。     

Experimental study and numerical simulation of the sludge concentration in a sedimentation tank

Sedimentation tanks and clarifiers play a significant role in an active sludge system, and the efficiency of the whole system is closely related with the design and operation of the sedimentation tanks. This paper focuses on the sludge concentration in each cross-section of the sedimentation tank. We measured the sludge concentration to explore its distribution inside the tank, carried in-situ tests to research the fluid pattern and real operational rules of the sedimentation tank. We also used the computational fluid dynamics (CFD) software, PHOENICS 3.5, to simulate the solid-liquid two-phase fluid inside the tank and describe the sludge concentration distribution. The numerical results indicate obviously a sludge-water interface and a compression interface inside the sedimentation tank, a stratified sedimentary region with uniform concentration and a compression region with high concentration at the bottom of the tank. Although the simulated concentrations deviated slightly from those of in-situ tests, they were still acceptable for identifying the sludge interfaces and fluid pattern inside a sedimentation tank, which are important parameters for optimizing the tank size and improving the settling efficiency.     

用于被动力/力矩再现的新型磁流变液阻尼器

研制了一种用于被动力/力矩再现的新型磁流变液阻尼器,该阻尼器能够在磁场的作用下产生连续变化的阻尼力/力矩.阻尼器的结构包括一个上盖和一个下盖,一个转子设置于上盖和下盖之间,转子与上下盖之间的间隙充满磁流变液,在磁场作用下其粘度变大时,转子相对于壳体将受阻尼力作用.阻尼力矩的模型主要由以下几部分组成:一是由磁场作用于磁流变液产生的力矩,二是由磁流变液的动力粘度产生的力矩,最后是由装置的摩擦产生的力矩.由动力粘度产生的力矩可以通过简单的方法进行计算,由摩擦产生的力矩可以通过实验测得,而由磁场产生的力矩则要通过电磁场的有限元分析得到.最后,对研制的阻尼器原型进行了性能实验,检验了设计方法的有效性.     

基于电阻层析成像技术的弹状流实验研究

在气液两相流研究中,相分布、相速度等流场特征信息对深入了解流动机理、提高模型计算精度有重要意义,但由于气液流动的复杂性与随机性,使得它们的准确测量较为困难。该研究基于快速电阻层析成像技术,首先对垂直向上气液管流中弹状流流型下多种工况的流动结构进行图像数据采集与重建;然后通过互相关算法得到轴向速度场分布,并与漂移流模型进行对比;再对按时序排列的横截面图像序列进行调整得到正确比例的空间三维图像;最后获得段塞长度、频率等特征信息。结果表明,快速电阻层析成像技术可以测得速度场分布、段塞长度、频率等特征信息,可用于优化与这些参数相关的理论模型和经验关系式,有助于提高气液两相流的模型计算精度。     

福建省中考命题改革的实践探索与展望

福建省根据近些年中考改革实践经验,提出“一核三层三翼”的中考评价体系,作为中考命题改革的指导理念“。一核”指中考的核心功能,包括立德树人、遵循课标、有利发展“;三层”指考查内容,包括核心价值、学科基础和行为习惯;“三翼”指考查要求,命题应遵循基础性、应用性、发展性原则。福建中考命题重点从3个方面推进改革：将落实立德树人根本任务融入评价改革,推进以课程标准为核心的“教—学—评”一体化改革,落实“双减”要求、注重教考衔接。未来福建中考命题改革应继续探索“学科+生活”的命题方向,强化核心素养考查,加强考试内容改革,引导培育创新人才。     

农垦58A花粉败育过程花药吲哚乙酸氧化酶活性

光敏感核不育水稻,在长日诱导的不育花药中,可溶性蛋白质含量,比短日诱导的可育花药为低;在花粉母细胞发育期和单核早期,不育花药中吲哚乙酸氧化酶总活性和比活性,均较可育花药高得多;单核晚期以后,酶活性仍以不育花药较高。     

Vapor-liquid equilibrium simulation of binary and ternary mixtures of CH4, C2H4 and iso-C4H10

The vapor-liquid equilibrium（VLE） properties for the binary and ternary mixtures of CH4,C2H4 and isoC4H10 are of great importance in the recovery of ethylene from mixture containing CH4 and C2H4 with iso-C4H10 as solvent.Hence,Gibbs ensemble Monte Carlo（GEMC） simulations were used to estimate vapor-liquid equilibrium for the binary and ternary mixtures of CH4,C2H4 and iso-C4H10 with the united atom potential NERD model.The selected simulation conditions are based on the experiment in the literature.The results of this work were shown to be in satisfactory agreement with available experimental data and predictions of Peng-Robinson equation of state.The structure of simulated liquid phase is also characterized by radial distribution function（RDF）,which contributes to further understanding of the VLE curve of these systems.RDF is not sensitive to the pressure and temperature range.With the increase of pressure or the decrease of temperature,the molecules tend to gather together.     

也说“课核”的选定

语文阅读教学应善于寻找文本中可聚合又可辐射的"课核"。需要注意的是,其一,课之"核",自然不是指整堂课本身,而是整堂课的一个核心"点";其二,凭着耐心、毅力与执着的专业追求,准确解读文本,深入把握文本精髓,在此基础上才能形成好的"课核";其三,选定"课核"的途径或日基本方法在于,依据备教中教师自身的疑难点确立"课核"以及依据文本的核心价值确立"课核"。     

影响醛和酮与亚硫酸氢钠加成反应的因素

本文从电子效应和空间效应，亲核试剂三个方面论述了醛和酮发生亲核加成的难易，从结构上说明了用亚硫酸氢钠可鉴别醛和酮的范围，其结果与实验事实完全一致。