教材教法知识在多媒体电子课件中的应用

本文根据多媒体电子课件的特点、教材教法知识，特别是化学教学原则在多媒体电子课件中的应用作了一些探讨。     

BRISOL放射性核束鉴别装置的研制北大核心CSCD

中国原子能科学研究院已经建成一台"在线同位素分离器"(BRISOL),在线产生并分离出需要的放射性离子束用于天体物理、核结构和材料科学等研究。其中研制的放射性核束鉴别装置,用来测量并鉴别能量30～300 ke V、束流强度在10~4～10^(11)Particle/s放射性离子束(RIB)的种类。介绍了该装置的原理、组成及调试结果。该装置结构紧凑,可在有限空间内完成核素的积累、转运和能谱测量。该装置已经用于"在线同位素分离器"的在线调试,通过在线获取的射线能谱确认了产生的38K+放射性同位素并给出放射性束流的强度。     

Effect of chloride introduction on the optical properties in Eu~(3+)-doped fluorozirconate glasses

Fluorozirconate glass containing Eu~(3+) ions and chloride ions are prepared by a meltquenching method. The luminescence behavior of Eu~(3+) affected by Cl ions is investigated. With increasing Cl ion concentration, the luminous intensity of Eu~(3+) is significantly enhanced and the quantum efficiency of fluorozirconate glass is improved. Meanwhile, the intensity parameter ?_2 increases according to the Judd–Ofelt calculation, which indicates the decrease of local symmetry. The average lifetime of Eu~(3+) increases by introducing the Cl ions. Moreover, we find two kinds of sites for Eu~(3+)ions in a glass network by analyzing the fluorescence decay. The distribution of Eu~(3+) ions changes with increasing Cl ion concentration.In addition, the excessive Cl ions lead to the separation of the glass phase and the formation of the crystal phase, thus reducing the transmittance dramatically.     

Temperature-dependent photoluminescence of size-tunable ZnAgInSe quaternary quantum dots

Colloidal ZnAgInSe (ZAISe) quantum dots (QDs) with different particle sizes were obtained by accommodating the reaction time. In the previous research, photoluminescence (PL) of ZAISe QDs only could be tuned by changing the composition. In this work the size-tunable photoluminescence was observed successfully. The red shift in the photoluminescence spectra was caused by the quantum confinement effect. The time-resolved photoluminescence indicated that the luminescence mechanisms of the ZAISe QDs were contributed by three recombination processes. Furthermore, the temperature-dependent PL spectra were investigated. We verified the regular change of temperature-dependent PL intensity, peak energy, and the emission linewidth of broadening for ZAISe QDs. According to these fitting data, the activation energy (ΔE) of ZAISe QDs with different nanocrystal sizes was obtained and the stability of luminescence was discussed.     

类星体中Balmer线的Cerenkov红移

利用Cerenkov线发射理论,本文估算了Balmer线的Cerenkov红移,较好地解释了类星体中高价离子宽发射线相对于氢宽Balmer线及低价离子宽发射线有蓝移这一观测事实。     

类星体的极软X过剩

在强软X类星体样品中,我们根据用Einsten天文台IPC决定的N_H与银河21cm线决定的N_H值的关系,构成极软X过剩类星体样品,并导出在0.3keV和0.5keV之间的X谱指数α_E。α_E明显大于0.5—3.5keV间的谱指数α_E。这表明0.3—0.5keV正是类星体紫外到X段大包右侧的急剧下降部分。这些结果将有助于导出这类类星体紫外到软X大包的组合模型。     

对高师开设多媒体技术与现代化学教育课程的探讨

以在高师怎样开设多媒体技术与现代化学教育课程为主题 ,结合应用和需求进行分析 ,围绕教学目标与内容 ,教学中的要点与难点及教学效果进行了讨论     

化学积件思想的形成、实现与展望

本文就积件思想的形成、积件的实现及展望做了探讨。着重介绍了化学积件开发应具备的多媒体基础知识、化学积件编制内容的选择及一些特殊素材的收集方法。