利用智能手机测定补铁药物中的铁含量*

为进一步提升图像比色法测定补铁药物中铁含量的准确性及普适性,考察了拍摄环境对结果的影响,确定了适用于图像比色分析的定量参数,比较使用不同容器来盛装溶液所获得的比色结果,在最优条件下测定了实际样品中铁的含量及加标回收率。结果显示,获得可靠数据的关键是将标准溶液、待测液以及空白溶液拍摄在同一张图片上;由溶液图像R值换算的吸光度值与浓度具有最佳的线性关系;分析以比色皿、试管、点滴板为容器获得的溶液图片,都能得到适合于定量比色分析的数据;测定的加标回收率大于95%。该方法操作简便,测定结果准确,可在各种条件下的高中化学实验室中开展。     

Synthesis,Structure and Property of a Novel Coordination Polymer [Tb(C_7H_3NO_4)(C_6H_4NO_2)(H_2O)]

A novel terbium(III) coordination polymer [Tb(C7H3NO4)(C6H4NO2)(H2O)] was successfully synthesized hydrothermally and characterized by single-crystal X-ray diffraction. The complex is of monoclinic, space group P21/c with a = 9.2252(11), b = 14.1477(16), c = 10.5134(12) A, β = 95.770(2)°, V = 1365.2(3) A3, Z = 4, Dc = 2.248 g·cm-3, F(000) = 880, the final R = 0.0176 and w R = 0.0411 for 2149 observed reflections with I 2σ(I). The complex is extended into a three-dimensional network structure with 24-atom rings which are composed of Tb, C and O atoms. The complex displays green fluorescence emission in the solid state at room temperature, which corresponds to 5D4 → 7F5 transition of the Tb(III) ion.     

有机-无机复合物[H2(PW12O40){Zn(C10H8N2)2(H2O)}]·1.5[Zn(C10H8N2)3]·1.75H2O的合成、结构及性能

An organic-inorganic hybrid complex, [H₂(PW₁₂O₄₀){Zn(C₁₀H₈N₂)₂(H₂O)}]·1.5[Zn(C₁₀H₈N₂)₃]·1.75H₂O has been synthesized hydrothermally and structurally characterized by X-ray crystallography. The crystal belongs to monoclinic, space grounp C2/c, with a=4.709 4(2) nm, b=1.431 77(7) nm, c=2.621 07(1) nm, β=90.125(4)°, V=17.673 4(2) nm³, Z=8, D_c=3.087 Mg·m^-3, F(000)=14 884, μ(Mo Kα)=16.327 mm^-1. The structure was refined to R₁=0.068 7 and wR₂=0.158 0 for 20 128 observed reflections with I>2σ(I). Single crystal structure shows that the title compound is constructed from [PW₁₂O₄₀]^3- cluster anion and [Zn(C₁₀H₈N₂)₂(H₂O)]²⁺ metal-organic complex cation, in which metal Zn(Ⅱ) cation are coordinately bonded to the terminal oxygen of Keggin polyanions. The title compound exhibits good catalytic activity for oxidation of benzaldehyde to benzoic acid. CCDC: 624772.     

一种有机-无机电荷转移配合物的合成、结构及性能研究

A charge-transfer complex, [(C₂H₄OH)₃NH]₂·[HPMo₁₂O₄₀]·3H₂O, has been synthesized and characterized.The crystal structure of the complex was determined by X-ray diffraction. It belongs to orthorhombic, space grounp Pnna, with a=1.541 30(5) nm, b=1.884 23 (7) nm, c=2.049 06(7) nm, α=β=γ=90.00°, V=5.950 8(4) nm³, Z=4, D_c=2.427 Mg·m^-3 , F(000)=4 132, μ(Mo Kα)=2.568 mm^-1. The structure was refined to R₁=0.043 5 and wR₂=0.122 4 by full-matrix least-squares method. The O atoms of the polyoxometalate, the C atoms of the organic substrates and the O atoms of water molecules are involved in hydrogen bonding. Spectral data support the presence of an electronic interaction between the organic substrate and the inorganic anion in the solid state. It is strongly photochromic under ultraviolet light resulting from charge-transfer. The electrochemical behavior of the compound shows that the redox peak currents are proportional to the scan rate in pH=4.0 NaAc-HAc buffer solution, which indicates that the electrode reaction are surface controlled processes.     

氢气燃烧火焰颜色影响因素的研究及演示方案再设计

基于对氢气燃烧火焰颜色的不同解释,从焰色反应、火焰温度、气体流速等3方面影响因素设计方案进行实验研究,得出影响氢气火焰颜色的主要因素是气流速度、火焰温度及药品的焰色反应。巧用球形干燥管既控制气流速度、又控制火焰温度的特点,设计出可以观察到氢气燃烧火焰呈明显蓝色的演示装置。用可现取的仪器药品、可执行的实验方案、可重现的实验现象、可检验的实验结果,验证了教材中关于氢气燃烧火焰颜色的论述,突破了实际操作中氢气燃烧颜色不易观察的局限。     

Synthesis,Structure and Luminescent Property of an Europium(Ⅲ) Coordination Polymer

A novel europium(Ⅲ) coordination polymer, [Eu3(pydc)3(SO4)(H2O)5(ox)0.5]·3H2O(1, H2 ox = oxalic acid, H2 pydc = pyridine-2,6-dicarboxylic acid), has been synthesized hydrothermally from the self-assembly of lanthanide ions(Eu3+) with the flexible oxalic acid and the rigid pyridine-2,6-dicarboxylic acid ligands, respectively. It crystallizes in the triclinic system, space group P1 with a = 11.225(4), b = 12.390(5), c = 13.752(5)A, α = 89.228(7), β = 71.142(6), γ = 75.552(6)°, Dc = 2.317 g/cm3, μ = 5.480 mm-1, F(000) = 1150, Z = 2, the final R = 0.0351 and w R = 0.0949 for 8782 observed reflections with I 2σ(I). Structural analysis reveals that complex 1 exhibits a three-dimensional metal-organic framework via π-π stacking interactions. In addition, complex 1 displays a red fluorescence emission in the solid state at room temperature, which corresponds to the 5D0 → 7F2 transition of Eu3+ ions.     

基础科学教育应把握好范畴及边界——以中学化学中结晶(重结晶)问题的教学为例

分析和阐述了结晶（重结晶）的基本原理，以课程标准为依据对结晶（重结晶）问题进行了教学要求的解析。认为，中学化学中的结晶（重结晶）问题的教学目标，不是结晶学的学科知识教学，也不是单纯的实验技能和方法培养，而应是围绕“溶解度及其应用”这一核心概念展开的辅助教学；认知边界应是溶解度概念在分离和提纯应用上的理解；把握基础科学教育内容的认知边界，是科学研究与科学教育、科学研究成果与科学教育素材的区别所在。     

基于化学学科核心素养发展的试题测量目标分析及启示*——以2019年全国高考Ⅰ卷部分化学试题为例

从2019年全国高考Ⅰ卷理综化学试题中,选择物质性质及应用、化学实验和化学反应原理等3个典型内容领域的3道选择题,基于化学学科核心素养发展进行试题测量目标分析。淡化具体知识的识记要求、强化基于核心主干知识支撑下的有效认识、分析和解决问题的综合能力,是高考的价值取向和素养导向。教师对试题的分析应从“知识为本”走向“素养为本”,素养立意的高考试题呼唤课堂教学转型,教师需加强对课堂转型内涵及其要求的认识。     

回归“精准施训”的逻辑原点*——《中小学幼儿园教师培训课程指导标准》应用解读

“精准施训”是破解中小学教师培训针对性、实效性和可持续性问题的关键。通过对“精准施训”逻辑原点的思辨,解读了《中小学幼儿园教师培训课程指导标准(初中化学学科)》是什么、做什么,并以“2019年‘国培计划'--示范性综合改革项目福建教育学院培训课标(初中化学)班”的实践,探索了该指导标准怎么做和怎么做得更好。认为“精准培训”应回归学科教育和学科育人的本质;基于“学科整体理解”的研修,可以强化学习者对“学科育人”问题的真思考;融入“教师能力层级自我诊断”的课堂实践研修,可以破解需求调研和分层施训的难题;强化“听课观摩”实践性课程的研修目标,可以提升学习者对教学能力的自我诊断水平。     

组合法在化学仪器创新中的运用*——以工业制备盐酸演示装置的设计为例

创新科学仪器具有重要意义,组合法是创新的常见方法。采用主体附加法为主、其他组合法为辅的创新手法,以教材中的电解饱和食盐水的装置、习题中的氯气与氢气燃烧的装置为主体,将简易启普发生器装置、氯化氢尾气防倒吸装置、氢气肥皂泡燃烧验纯法等作为附加部分进行有机组合,设计出工业制备盐酸的新演示装置。总结出组合法在化学仪器创新中的应用步骤,有利于推广运用。