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1.
何鹏 《化学教育》2022,43(13):13-22
“教、学、评”一体化是确保化学学科核心素养课程顺利实施的重要举措。如何基于课程标准进行“教、学、评”一体化目标设计是当前化学教育理论与实践研究所共同关注的课题。引进国际科学教育领域中学习表现性目标理念,基于整合式化学学科核心素养视角,采用结构中心设计原则和证据中心设计原则作为设计方法论,构建了基于课程标准的化学学习表现性目标设计框架。并以“2.2 氧化还原反应”专题为例,阐述该专题下化学学习表现性目标的设计过程以及基于该目标的“教、学、评”一体化的活动设计,以期对基于化学学科核心素养的课堂教学与评价研究和实践提供新视角和思路。  相似文献   

2.
胡晶  李佳  吴鑫德 《化学教育》2020,41(4):44-51
化学教师化学建模能力水平的高低直接影响着所培养学生建模能力的强弱。基于Rasch模型从模型表征能力、模型建构能力、模型应用能力3个维度开发四水平测查的《职前化学教师化学建模能力问卷调查》,对83名职前化学教师的化学建模能力进行测评,研究发现:被调查的职前化学教师化学建模能力总体较差,参照《普通高中化学课程标准(2017年版)》对化学建模能力的具体要求,分别仅有88%、42%、54%的职前化学教师的模型表征能力、模型建构能力、模型应用能力达标。因此,建议高等师范院校加强对职前化学教师化学建模能力的培养。  相似文献   

3.
吴曼 《化学教育》2023,(23):14-20
科学探究是化学学科核心素养之一,而探究性试题是检验学生探究能力及思维品质的重要方式。按照科学探究的过程,结合现有的纸笔考试形式,可将探究性试题中的探究要素分为提出问题、猜想与假设、制定计划、进行验证、获取证据、解释与结论、反思与评价、迁移与应用等几个方面。命制化学探究性试题时,要根据化学学科核心素养的培养目标,科学、灵活地设计探究环节中的各要素,有效提升探究性试题的考查功效。  相似文献   

4.
汪峰 《化学教育》2009,30(8):34-36
2009年安徽省实施普通高中新课程实验后的第一年高考.试题以<普通高中化学课程标准(实验)>和<2009年普通高等学校招生全国统一考试安徽卷化学科考试说明(理科·课程标准实验版)>为依据,结合全省化学新课程的教学实际,以测试化学科学素养和综合能力为主导,考查了考生对化学基础知识、基本技能及基本方法的掌握程度以及分析和解决具体问题的能力、自主学习的能力.  相似文献   

5.
杨水华  王丹  王秋 《化学教育》2019,40(11):18-23
以近4次TIMSS科学测评为研究对象,分析其测评框架及发展趋势,从试题结构、知识与能力、信息呈现和情境设计等方面分析TIMSS测评已公开的化学相关试题特点,对我国中学化学教学和教学评价提出可行性建议。  相似文献   

6.
美国加州CSTs标准化测试是基于课程标准下对学生的学业成就进行评价并生成报告的一种评价方式。本文主要介绍了CSTs标准化测试的形式及其化学试题,并分析了试题特点,以期为我国学生的化学学业评价提供一些有益的参考。  相似文献   

7.
吴明好  李银秀 《化学教育》2021,42(21):34-40
在新课程标准和高考评价体系的背景下,如何提高化学学科的命题质量?通过以学术探索情境为载体命制选择题和以实验探究情境为载体命制非选择题的2例,展示了在双向细目表的指引下,检索文献、初拟试题、打磨试题和要素分析的过程,剖析了精炼试题语言表述、核实信息来源、优化信息呈现方式和调整测试任务的各环节,总结了依靠团队合作精心筛选命题素材、创设真实问题情境、科学设计测试任务、反复推敲打磨试题的命题经验。  相似文献   

8.
朱国富 《化学教育》1996,17(6):23-25
作为一门中心科学,化学在其发展过程中大量地吸收、借鉴、融合了许多相关学科的科学原理.因而测试学生综合运用相关学科的科学原理(结合化学原理)解决化学间题的能力自然成了近几年高考(竞赛)化学试题的一大特色,也是今后高考(竞赛)试题发展的趋势之一.  相似文献   

9.
汤小梅 《化学教育》2022,43(1):76-79
设计受控实验是科学实验实证的重要手段,这种科学探究的核心能力,也是教育部在《普通高中化学课程标准(2017年版2020年修订)》中对学生能力的评价之一.在分析学生能力现状、教材内容后,经过教学实施,充分利用教材,帮助学生认识变量控制要素,达成能系统地综合应用变量控制解决实际问题的教学目标.  相似文献   

10.
李川  刘敬华 《化学教育》2021,42(13):14-20
《普通高中化学课程标准(2017年版)》的颁布,开启了我国化学学科核心素养导向的教学实践的新时代。美国高中阶段实施的2019版AP化学课程凸显科学实践的课程目标,以4个化学大概念为依据选择、组织课程内容,倡导教、学、评一体化的教学策略,开展以学生为中心的引导性探究实验,设计多样化的评价任务。对比我国现行化学教学实践中缺少大规模教、学、评一体化平台,科学解释和论证能力目标外显不足,教师难以建立化学知识与学科观念素养间联系的现状,提出聚焦课程目标建设过程性评价体系,深度挖掘教学内容背后的科学解释和科学论证能力要求,深入理解知识承载的认识功能和价值等思考。  相似文献   

11.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

12.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

13.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

14.
The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.  相似文献   

15.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

16.
KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.  相似文献   

17.
The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.  相似文献   

18.
A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.  相似文献   

19.
Zhanhui Yang  Shiyi Yang  Jiaxi Xu 《Tetrahedron》2017,73(23):3240-3248
Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.  相似文献   

20.
A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.  相似文献   

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