大学无机化学与高中化学知识衔接——以原子结构与元素周期表为例

原子结构理论是高中化学和大学无机化学的重要组成部分和学习难点,教学过程中如何较好地衔接高中阶段知识与大学无机化学课程尤为重要。本文以原子结构和元素周期表知识点为例,以2019版高中人教版教材和北师大版的无机化学教材内容讨论高中化学知识与大学化学知识的衔接问题,依据作者的教学实践提出若干建议,为大学无机化学原子结构与元素周期表知识点的教学提供参考,同时帮助大一学生顺利完成知识的衔接过渡和培养学生独立思考、自主学习的能力。     

高中化学与大学无机化学教材知识点的衔接研究*

作为化学教育专业的必修课程,无机化学起到了奠定师范生化学理论基础的重要作用。在衔接高中化学知识的前提下,开展大学无机化学教学有助于构建完整的化学知识教学体系、调动师范生学习的积极性,实现高中到大学无机化学课程学习的顺利过渡。笔者在教学实践、教育实习指导及调研的基础上,以人教版高中化学、北师大版《无机化学》教材内容为例,从教与学的角度探讨了高中化学和大学无机化学教材知识点的衔接情况,形成了部分经验积累和教学建议,为师范类专业认证背景下的无机化学课程教学提供借鉴和参考。     

以学生为中心探讨大学化学与高中化学教育的衔接——无机化学主题

基于阶段教育理论，通过调研大学一年级学生高中化学以及大学无机化学的学习情况，归纳高中化学和大学无机化学的联系与差别，了解学生学习的难点，把握教与学的关系，以学生发展为中心，结合实际教学情况探讨大学无机化学与高中化学的有效衔接问题，为大学无机化学课程教师开展教学工作提供依据和建议。     

深圳市初高中化学衔接教学的抽样调查与研究

深圳市在课改推进中关于化学课程的开设呈现多元局面。全市的初高中化学衔接教学抽样调查结果表明,学生进入高中学习,在化学知识准备、学习方法调试、人际关系重建和学习兴趣与动机激发等方面存在比较复杂的适应性问题,并且学生基础相对薄弱一些的学校总体上存在的适应性问题更多。提高化学教学质量、促进课改深入,需要加强教学研究与资源开发,从学生心理发展水平、知识结构、学法指导与学习兴趣与动机激发等方面做好专门性或渗透性的衔接教学。     

基于合作学习的化学课堂导学

阐述了基于合作学习的化学课堂导学,应适时地在学习目标处、概念关键处、认知冲突处、知识衔接处、实验失败处、思维障碍处和课堂生成处给学生引导和帮助。     

初高中化学知识衔接教学方法初探

学生刚刚由初中升入高中学习时,心中充满了兴奋和新奇感,因此引导学生在原有的知识层次上稳步迈上一个新的台阶,使学生在原有的基础上逐步接受新知识而不感到“力不从心”。就必须搞好初高中知识的衔接。     

高中化学新课程必修与选修的衔接教学

做好必修与选修课程的衔接教学,需准确把握2者之间的连接,处理好3种关系,整合好3类知识,做好3个衔接要点,切实帮助学生尽快适应选修课程的学习,实现新课程的目标,提高学生素养,促进学生的个性发展.     

高中与大学有机化学教学衔接的实证研究——以烃的含氧衍生物为例

针对各大高校有机化学教学中出现“教师教学难进行,学生学习学不会”的现象,从教学衔接的角度出发,在对比高中《有机化学基础》与大学《有机化学》中“烃的含氧衍生物”知识点的基础上,通过问卷调查来了解有机化学课程实施现状,并从教学目标、教材内容、教与学的方法、教学衔接意识与行动等角度提出了教学衔接的参考建议。     

高一化学教学一体化衔接模式初探

在新课程改革背景下,从尚未启动高中化学课改的学校的视角出发,将高中化学与初中化学对学生学习知识的难度和能力的要求、教师的教和学生的学等方面进行了对比分析,结合教育教学实际,对高一化学教学一体化衔接模式进行了初步探究。     

初高中化学教学衔接教师应做好3件事

高一学生不适应高中化学学习,与教师对初中内容的淡化和对学生的学法指导不到位有直接的关系。做好初高中化学教学衔接,教师要做好课程内容、考点和学习方法3方面的衔接。     

充满生机和科学机遇的磷化学研究所

简要地综述了第十五届国际磷化学会议的报告内容，介绍了目前磷化学的主要 研究领域，包括不对称合成、配合化学，生物碱化学，药物化学，农业化学等相关 领域的研究动态及新进展。     

Novel arylpyridine‐based 1,3,4‐oxadiazoles: Synthesis,antibacterial, and anti‐inflammatory evaluation

In view of developing novel bioactive compounds, a series of 2‐(5‐[2‐methyl‐6‐arylpyridin‐3‐yl]‐1,3,4‐oxadiazol‐2‐ylthio)‐1‐arylethanones (6a–n) were designed and synthesized in good yield. Novel compounds were evaluated for their antibacterial and anti‐inflammatory activities. All synthesized compounds were screened for their antibacterial activity against Staphylococcus aureus, Bascillus subtilis, Eschericia coli, and Pseudomonas aeruginosa strains. Compounds 6a , 6b , 6c , 6h , and 6i displayed the highest antibacterial activity with minimal inhibitory concentration (MIC) values ranging from 6.25–12.5 μg/mL in comparison with the standard Ciprofloxacin. The results of anti‐inflammatory activity of carrageenan‐induced footpad edema assay indicated that tested compounds exhibited remarkable anti‐inflammatory activity with percentage of inhibition of 63.9–70.1% (potency 96.8–106.20% of indomethacin activity) after 3 hr. Particularly, 6c – e and 6j – l were found to be excellent inhibitors of inflammation, with potential higher than that of the standard, Indomethacin.     

Biologically inspired 3Fe4S cluster as structural mimics of FeMoco M-cluster

A 3Fe4S cluster related to M-cluster of Mo-nitrogenase is reported. [K(THF)₅][Fe₃(μ-bdt)₂(μ-PPh₂)(CO)₅] ( 1 ) is synthesized from photo-assisted structural rearrangement of [K(THF)₂][(μ,κ²-bdt)Fe₂(μ-PPh₂)(CO)₅] under visible light irradiation. The molecular structure of 1 consists of a Fe₃ core bearing one dithiolate bridge and the second dithiolate group capping onto the metallic plane. The structural motif of 1 is analogous to that of Mo-participated 3Fe4S unit in M-cluster of Mo-nitrogenase, with the similar Fe-Fe and Fe-S bond distances. Upon protonation in 193 K, a Fe-hydride species ( 1H ) is generated and characterized to possess the bridging hydride group (δ = −12.57 ppm) by ¹H-NMR spectroscopy and DFT calculation. In CH₃CN solution, complex 1 exhibits a reversible reduction and oxidation process at $E_{1/2}^{\mathrm{red}}$ = −1.94 V and $E_{1/2}^{\mathrm{ox}}$ = −0.18 V, respectively, at 273 K. The reduction behavior of 1 in CH₂Cl₂ solution at 243 K displays a slight modification in the presence of trifluoroacetic acid, revealing a moderate anodic potential shift (~50 mV). The current amplitude of the reduction wave is linearly increased with the increasement of acid added, indicative of the catalytic event.     

Novel [1,2,4]triazolo[3,4-b][1,3,4]thiadiazine derivatives embedded with benzimidazole moiety as potent antioxidants

Fourteen novel [1,2,4]triazolo[3,4-b][1,3,4]thiadiazine derivatives bearing benzimidazole moiety ( 7a-n ) have been synthesized using the one-pot nitro reductive cyclization method. All the synthesized compounds were confirmed by ¹H nuclear magnetic resonance (¹H NMR), ¹³C NMR, fourier-transform infrared (FT-IR), mass spectrum, and elemental analyses. All the title compounds were subjected to in vitro antioxidant activity. The free radical scavenging activity of the compounds was examined using DPPH, nitric oxide, and superoxide radical scavenging methods. The results demonstrated that compound 3-(2-(3,4-dimethoxyphenyl)-1-propyl-1H-benzo[d]imidazol-5-yl)-6-4-tolyl-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazine ( 7c ) was potent in scavenging both DPPH and nitric oxide radical with IC₅₀ values of 13.57 and 18.55 μg/ml when compared to the standard with IC₅₀ values of 23.75 and 23.14 μg/ml, respectively, which was due to the presence of electron-donating groups. The activity was found to decline when electron-donating groups were replaced by electron-withdrawing groups. Moderate scavenging activity was observed for the superoxide radical. Structure activity relationship and physiochemical properties were studied for all the derivatives.     

Exploring recent developments on 1,2,4-triazole: Synthesis and biological applications

Triazoles are nitrogen-bearing heterocycles. In the last few decades, researchers have focused on fused heterocycles, as they have better pharmacological effect compared to triazoles alone. Among the two isomers of triazole, this article aims to explore the work carried out on 1,2,4-triazole and N-bridged heterocycles derived from 1,2,4-triazole in last 18 years, highlight different synthetic pathways, and present a brief summary of the different biological activities possessed by 1,2,4-triazole derivatives. The information collected in this article is expected to help researchers to discover novel therapeutic agents for better applications in the field of pharmaceutical science.     

Dual zinc catalysts for L‐lactide polymerization and reaction of CO2 with cyclohexene oxide

A series of zinc complexes, [ L ^X ZnEt] ( 1–5 ) and [ L ^X Zn ₂ (OAc) ₃ ] (6–9) , associated with NNO‐tridentate Schiff base ligands (2‐(((2‐((cyclohexyl[methyl]amino)methyl)phenyl)imino)methyl)phenolate (CAP) derivatives), were synthesized, and their activity toward ring‐opening polymerization (ROP) of L‐lactide (LA) and the reaction of CO₂ with cyclohexene oxide were also investigated. All of [ L ^X ZnEt] revealed excellent catalytic activity to ring‐opening polymerization (ROP) of LA in the presence of benzyl alcohol. Among them, [ L ^H ZnEt] (1) showed the highest activity with 82% conversation within 45 s. In contrast, [L ^X Zn ₂ (OAc) ₃ ] (6–9) were inactive in ROP of L‐lactide. In addition, all of these Zn complexes demonstrated moderate activity in the reaction of CO₂ with cyclohexene oxide in the presence of Bu₄NCl.     

环戊二烯类有机金属含硫族化学的新进展

本文系统地综述了环戊二烯类有机过渡金属含硫族(S, Se, Te) 化学领域的研究现状和进展。参考文献136 篇。     

化学学科的新视角及其在化学教育中的反映

传统化学以研究变化,关注变化前后的结果而著称。化学与其他学科,特别是生命科学的相互渗透使得化学的动态特征更加突出,化学学科格局也因之发生了变化。因此,化学需要新认识。     

Meeting the sustainable development goals in a tropical climate

This article reflects on the Federation of Asian Chemical Societies (FACS) Citation Award Lecture delivered in the Industrial Technology Research Institute Symposium on CO₂ Utilization and Green Technology during the 18th Asian Chemical Congress held in Taipei, December 12, 2019. Malaysia produces sizable amounts of palm oil and palm kernel oil, with palm fronds and tree trunks as the main waste. At the Malaysia Japan International Institute of Technology, the biomass was decomposed to produce fine chemicals, used as substrate for mushroom growth, and converted to bio-coke for heat energy. A notable difference has been found regarding the emission of greenhouse gases from a natural peat forest and those from the oil palm plantation converted from peatlands, where in the palm plantation, water table is lowered and aerobic processes occurs, resulting in more CO₂ being released compared to CH₄. The introduction of fertilizers to the plantation resulted in more N₂O being released. The team has also pioneered a project to plant temperate vegetables. Cooling pipes (16–18°C with circulating water cooled by chiller) were embedded within each thermal conditioning soil plot. Lettuce and radish, the experimental plants, showed good growth in the thermal conditioning soil due to nitrogen-fixing bacteria, which were destroyed at a higher temperature.     

The Chemistry of Protactinium

Protactinium exhibits an ambivalent chemical behavior. In non-aqueous solutions and in the solid state, both quadrivalent and quinquevalent protactinium has properties which characterize it as a typical actinide element. On the other hand, investigations in aqueous solution show quinquevalent protactinium to be a homologue of niobium and tantalum. It exhibits – except in hydrofluoric acid solutions – a marked tendency to undergo irreversible hydrolysis and condensation reactions, which leads to the situation that tracer amounts (ca. 10^?12 mole/l) and macroscopic amounts (10^?3–10^?6 mole/l) of protactinium often behave differently. Reduction with strong reducing agents gives aqueous solutions of Pa(IV), the properties of which again correspond in general to those of Th(IV) and show no relation to Nb(IV). Our knowledge of the chemical behavior of this rare radioelement has been advanced, in particular, by the production in 1958–1960 of 100 g of pure protactinium – the largest amount so far – from residues of the British production of uranium.