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按照高等职业技术教育的教学规律,说明了学科交叉型教学的必要性,并进行了高职精细化工专业学科交叉型教学的构建实践,探讨了学科交叉型教学经验. 相似文献
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学科交叉融合是前沿重大科学研究的重要特征,是学科原始创新及新学科产生的重要路径,更是拔尖创新人才培养的重要模式。学科交叉融合的根本目的在于打破传统学科之间的壁垒,运用知识的融通培养拔尖创新人才、开展跨学科研究创造新知识、解决前沿重大现实问题等。吉林大学未来科学国际合作联合实验室充分利用学科交叉培养人才的优势,整合化学学科和校内外、国内外优质资源,搭建多学科交叉科研平台,构建“大师-大平台-大学科”育人机制,产出原创性成果,促进化学学科原始创新。 相似文献
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完善评审机制是国家自然科学基金委新时代基金改革的重要任务之一。为切实落实该项改革任务,建立符合新时代科学基金资助导向的科学、公正、高效的评审机制,基金委化学部努力探索新的学科基金管理模式,尝试了在通信评审阶段由科学家与学科管理人员共同参与项目的分组、指派,共同完成同行评议专家遴选工作的新模式。本文分析了科学家参与同行评议专家遴选工作的利弊,探讨了如何更好的发挥科学家在同行评议专家遴选工作中的作用,建立学术共同体互信的基金评审机制。 相似文献
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以美国高中主流理科教科书Chemistry:Concepts and Application作为研究对象,选取了几则涉及“学科交叉”内容的典型案例进行介绍和分析,从当前基础教育课程改革的角度得出若干启示,为我国进行课改实践探索的高中化学教师提供教学中有关该内容选取和应用的认识参考。 相似文献
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自从20世纪20年代“高分子”概念建立之后,高分子学科和工业蓬勃发展,人类进入了高分子材料的新纪元。高分子材料在民生、安全和尖端科技等各个领域发挥着关键作用。作为全球制造业最大的国家,我国未来要在全球高分子材料领域处于引领地位,关键在于当前的大学基础教育要能培养出德才兼备的顶尖专业人才。浙江大学高分子科学与工程学系的高分子材料与工程专业具有典型的理工学科交叉性特征。本文结合该专业的核心必修课程《高分子化学》教学改革的例子,总结专业建设的探索和实践经验,探讨学科交叉背景下专业人才培养的两个基本问题:一是以培养理工结合型专业人才为目标的课程体系设置与建设,另一个是厚植正确价值观作为人才培养基石的课程教学实践。希望本文作者的教学实践经验和思考能为我国高分子材料与工程专业人才培养起到“抛砖引玉”的作用。 相似文献
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《化学教育》2010,31(Z2):341-347
一直以来元素化合物的单元教学是以知识的系统性和完备性为教学目标的,然而实际的教学效果并不理想。为此本研究提出了基于学科观念建构的元素化合物单元教学设计,目的在于通过观念建构实现知识的结构化和功能化,进而提高学生解决问题的能力。以山东科技版《化学1必修》教材中"硫的转化"单元为例,本研究提出以建构"转化观"为核心的单元教学目标,研究了"转化观"有效建构的2个重要标志,即学生能够自主建构以价态和类别为横纵坐标的二维物质转化关系图,能够利用转化关系及规律解决实际问题,实现观念的工具化。研究了有效建构"转化观"的教学策略:(1)由整体到局部的策略,即先建构转化关系再利用整体结构指导学生认识重要代表物的性质,实现思维的系统化、有序化和结构化;(2)从自然现象→实验室→工业生产→环境等多角度建构和应用转化关系,以实现知识的工具化;(3)依据各课时教学内容的特点,选择开放程度适当的教学方式,保证教学的实效性。以山东科技版《化学1必修》教材中"材料家族的元素"单元为例,提出了建构"材料观"的单元核心教学目标。具体而言,就是要帮助学生建立从化学的视角认识材料的思路和角度,即认识材料的性能、加工、制备、用途等与物质性质的关系。研究确立了教学的基本思路是:以铝为载体建构基本认识框架,以铝的重要化合物为载体深化认识思路和方法,最后应用该思路和方法认识硅及其化合物的性质与相关材料问题。在教学实践的基础之上,本研究对单元教学的实效性进行了分析,提出了基于学科观念及方法建构的元素化合物单元教学设计的一般思路和方法:明确单元核心基本观念及思想方法→选择与核心观念相匹配的知识载体→合理分配各部分知识载体的功能→合理设计单元中每一课时的教学情境、问题和学生活动→精心设计课时之间的衔接。 相似文献
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On the Ambiphilic Reactivity of Geometrically Constrained Phosphorus(III) and Arsenic(III) Compounds: Insights into Their Interaction with Ionic Substrates 下载免费PDF全文
Thomas P. Robinson Siu‐Kwan Lo Daniel De Rosa Simon Aldridge Jose M. Goicoechea 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(44):15712-15724
The ambiphilic nature of geometrically constrained Group 15 complexes bearing the N,N‐bis(3,5‐di‐tert‐butyl‐2‐phenolate)amide pincer ligand (ONO3?) is explored. Despite their differing reactivity towards nucleophilic substrates with polarised element–hydrogen bonds (e.g., NH3), both the phosphorus(III), P(ONO) ( 1 a ), and arsenic(III), As(ONO) ( 1 b ), compounds exhibit similar reactivity towards charged nucleophiles and electrophiles. Reactions of 1 a and 1 b with KOtBu or KNPh2 afford anionic complexes in which the nucleophilic anion associates with the pnictogen centre ([(tBuO)Pn(ONO)]? (Pn=P ( 2 a ), As ( 2 b )) and [(Ph2N)Pn(ONO)]? (Pn=P ( 3 a ), As ( 3 b )). Compound 2 a can subsequently be reacted with a proton source or benzylbromide to afford the phosphorus(V) compounds (tBuO)HP(ONO) ( 4 a ) and (tBuO)BzP(ONO) ( 5 a ), respectively, whereas analogous arsenic(V) compounds are inaccessible. Electrophilic substrates, such as HOTf and MeOTf, preferentially associate with the nitrogen atom of the ligand backbone of both 1 a and 1 b , giving rise to cationic species that can be rationalised as either ammonium salts or as amine‐stabilised phosphenium or arsenium complexes ([Pn{ON(H)O}]+ (Pn=P ( 6 a ), As ( 6 b )) and [Pn{ON(Me)O}]+ (Pn=P ( 7 a ), As ( 7 b )). Reaction of 1 a with an acid bearing a nucleophilic counteranion (such as HCl) gives rise to a phosphorus(V) compound HPCl(ONO) ( 8 a ), whereas the analogous reaction with 1 b results in the addition of HCl across one of the As?O bonds to afford ClAs{(H)ONO} ( 8 b ). Functionalisation at both the pnictogen centre and the ligand backbone is also possible by reaction of 7 a / 7 b with KOtBu, which affords the neutral species (tBuO)Pn{ON(Me)O} (Pn=P ( 9 a ), As ( 9 b )). The ambiphilic reactivity of these geometrically constrained complexes allows some insight into the mechanism of reactivity of 1 a towards small molecules, such as ammonia and water. 相似文献
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采用密度泛函理论B3LYP方法, 对两类金(I)配合物AuX (X=F, Cl, Br, I)和AuPR3+(R=F, Cl, Br, I, H, Me,Ph)催化C2H4加氢反应的机理进行了理论研究. 计算显示Au(I)配合物对C2H4氢化具有较好的催化效果, 其作用下的加氢反应存在“活化H―H键后再与C2H4反应”和“活化C=C键后再与H2反应”两种途径, 前者的活化能较后者低90-120 kJ·mol-1, 因而具有明显的能量优势. 研究表明AuPR3+ 的催化能力明显强于AuX. 此外, X/PR3基团供、吸电子能力的变化对配合物的催化能力也具有较为显著的影响. 电子结构分析显示Au(I)配合物在C2H4 加氢反应中不仅能够削弱H―H、C=C 键的强度, 还使H2 σH―H*、C2H4 πC=C* 轨道能级下降, 从而缩小了πC=C-σH―H*或σH―H-πC=C*轨道间的能级差, 促进了C2H4-H2反应中的电子离域, 从而降低禁阻反应发生的难度.σH―H*、πC=C*轨道能级改变量与加氢反应活化能Ea的降低值之间存在较好的一致性关系, 因此使上述轨道能级下降幅度越大的Au(I)配合物可以获得较好的催化效果. 相似文献
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SynthesesandCharacterizationsof(η~5-C_5H_5)MoFeCo(CO)_8(μ_3-S)and(η~5-C_5H_5)_2Mo_2Fe(CO)_7(μ_3-S):X-rayCrystalStructureof(η~5-C_5H_... 相似文献
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主要介绍了聚偏氟乙烯(PVDF)膜在近年来改性方法的最新研究进展,从辐照改性、等离子体改性、共混改性和化学改性等几方面进行了详细介绍,简要介绍了PVDF膜作为离子交换膜的一些最新应用. 相似文献
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本文用量子化学密度泛函方法对C3H2 (环丙烯基自由基)与O(3P)反应的机理进行了理论研究。在B3LYP/6-311++G**计算水平上优化了各驻点(过渡态,中间体,产物)的几何结构,在QCISD(T)/6-311++G**水平下计算了各物质的单点能量,在两种水平下计算了298K和600K时的能量。计算结果表明:C3H2 + O(3P) 反应可以生成P1 (C2H +HCO),P2 (C2H2 + CO) 和P3 (HC3O+H)三种产物。生成P1反应通道的能垒最低,即P1为主要产物,与实验的结果一致。产物P1可以通过路径:R→ IM1→ IM2→ P1获得。本文详细地讨论了C3H2 + O(3P) 的反应机理,并从理论上对实验结果进行了验证。研究结果有助于深入理解C3H2 + O(3P)反应机理以及C3H2在大气中的燃烧过程。 相似文献
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Prof. Attila K. Horváth 《Chemphyschem》2020,21(15):1703-1710
One of our most appealing challenge is to unravel the role of a presumably autocatalytic system in controlling the origin and spreading of Life on our entire planet. Here we show that in the simplest autocatalytic loop involving reactions capable of self-replication and obeying law of mass action kinetics, concentration growth of the autocatalyst may be characterized by parametrization of direct and autocatalytic pathways rather than by kinetic orders of the autocatalyst. Extending this model by feasible elementary steps allows us to outline super-exponential growth where kinetic order of the autocatalyst is higher than unity. Furthermore, it is shown in case of the simplest hypercycle that such a situation might appear where the otherwise more sluggish autocatalytic route receives a decisive support from the crosscatalytic pathway to become an apparently stronger autocatalytic loop even if the other route contains a more efficient autocatalysis. If the hypercycle is performed under flow conditions selection of autocatalyst depends on kinetic and flow parameters influenced by external factors mimicking that the most adaptive loop of hypercycle eventually finds its wining way in the evolutionary race. 相似文献
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Pablo Ortega Dr. Alexandre Zanchet Dr. Cristina Sanz-Sanz Dr. Susana Gómez-Carrasco Dr. Lola González-Sánchez Dr. Pablo G. Jambrina 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(5):1700-1712
Despite being a very strong oxidizing agent, most organic molecules are not oxidized in the presence of O2 at room temperature because O2 is a diradical whereas most organic molecules are closed-shell. Oxidation then requires a change in the spin state of the system, which is forbidden according to non-relativistic quantum theory. To overcome this limitation, oxygenases usually rely on metal or redox cofactors to catalyze the incorporation of, at least, one oxygen atom into an organic substrate. However, some oxygenases do not require any cofactor, and the detailed mechanism followed by these enzymes remains elusive. To fill this gap, here the mechanism for the enzymatic cofactor-independent oxidation of 3,5-dihydroxyphenylacetyl-CoA (DPA-CoA) is studied by combining multireference calculations on a model system with QM/MM calculations. Our results reveal that intersystem crossing takes place without requiring the previous protonation of molecular oxygen. The characterization of the electronic states reveals that electron transfer is concomitant with the triplet–singlet transition. The enzyme plays a passive role in promoting the intersystem crossing, although spontaneous reorganization of the water wire connecting the active site with the bulk presets the substrate for subsequent chemical transformations. The results show that the stabilization of the singlet radical-pair between dioxygen and enolate is enough to promote spin-forbidden reaction without the need for neither metal cofactors nor basic residues in the active site. 相似文献