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高水平大学研究生课堂教学质量评价的理论创新及应用研究
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作者 韩青松 钱晓田 +3 位作者 刘元 郭啸 朱锦松 刘伟诚 《前卫》 2022年第34期196-198,共3页
在我国有序推进教育评价改革的环境下,我国高水平大学尤其是普通高校的研究生课堂教学质量评价工作中还存在着一些问题,因此,有必要加强对研究生课堂教学质量评价的理论创新研究,以指导评价实践.本文在全面分析和总结以往两个主要教学... 在我国有序推进教育评价改革的环境下,我国高水平大学尤其是普通高校的研究生课堂教学质量评价工作中还存在着一些问题,因此,有必要加强对研究生课堂教学质量评价的理论创新研究,以指导评价实践.本文在全面分析和总结以往两个主要教学质量评价理论(第四代评价理论和全面质量管理理论)优缺点的基础上,基于教育评价改革视角,提出创新的教学质量评价理论,即多维度高精度评价理论,作为相关高校研究生课堂教学质量评价路径探索的指导和依据,助力推动教育评价改革和高校建设发展. 展开更多
关键词 研究生 课堂教学质量评价 理论创新 “双度”理论 高水平大学
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Interzeolite transformation from FAU to CHA and MFI zeolites monitored by UV Raman spectroscopy 被引量:4
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作者 Juan Zhang Yueying Chu +4 位作者 Xiaolong Liu Hao Xu Xiangju Meng Zhaochi Feng Feng-Shou Xiao 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第12期1854-1859,共6页
As a powerful and sensitive tool for the characterization of zeolite building units,UV Raman spectroscopy has been used to monitor interzeolite transformation from FAU to CHA and MFI zeolites.The results show that the... As a powerful and sensitive tool for the characterization of zeolite building units,UV Raman spectroscopy has been used to monitor interzeolite transformation from FAU to CHA and MFI zeolites.The results show that the behavior of double 6-membered rings(D6Rs)in the FAU zeolite framework plays an important role during the formation of the target product in the interzeolite transformation.For the transformation of FAU to CHA,because both zeolites contain the same D6R units,direct transformation occurs,in which the D6Rs were largely unchanged.In contrast,for the transformation of FAU to MFI,the D6Rs can be divided into two single 6-membered rings(S6Rs),which further assembled into the MFI structure.In this crystallization,5-membered rings(5Rs)are only observed in the MFI framework formation,suggesting that the basic building units in the transformation of FAU to MFI are S6Rs rather than 5Rs.These insights will be helpful for further understanding of the interzeolite transformation. 展开更多
关键词 Interzeolite transformation UV Raman spectroscopy DFT calculation Double 6-memberred rings Decomposition and re-assembly
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Designer Mg-Mg and Zn-Zn Single Bonds Facilitated by Double Aromaticity in the M2B7^-(M=Mg,Zn)Clusters
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作者 Wei Wang Jie Wang +3 位作者 Chu Gong Chaonan Mu Dongmei Zhang Xinxing Zhang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2020年第5期578-582,I0011-I0013,I0078,共9页
The simple homodinuclear M-M single bonds for group II and XII elements are difficult to obtain as a result of the fulfilled s2electronic configurations,consequently,a dicationic prototype is often utilized to design ... The simple homodinuclear M-M single bonds for group II and XII elements are difficult to obtain as a result of the fulfilled s2electronic configurations,consequently,a dicationic prototype is often utilized to design the M^+-M^+single bond.Existing studies generally use sterically bulky organic ligands L^-to synthesize the compounds in the L^--M^+-M^+-L-manner.However,here we report the design of Mg-Mg and Zn-Zn single bonds in two ligandless clusters,Mg2B7-and Zn2B7-,using density functional theory methods.The global minima of both of the clusters are in the form of M2^2+(B7^3-),where the M-M single bonds are positioned above a quasi-planar hexagonal B7 moiety.Chemical bonding analyses further confirm the existence of Mg-Mg and Zn-Zn single bonds in these clusters,which are driven by the unusually stable B7^3-moiety that is bothσandπaromatic.Vertical detachment energies of Mg2B7-and Zn2B7-are calculated to be 2.79 e V and 2.94 e V,respectively,for the future comparisons with experimental data. 展开更多
关键词 Mg-Mg single bond Zn-Zn single bond Density functional theory Double aromaticity Cluster
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Theoretical Study of Hydrogen-Bond Interactions of CO_(2) in Organic Absorbent 1,3-Diphenylguanidine
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作者 Yiqiu Wang Han Gao +2 位作者 Yajing Li Igor Ying Zhang Fei Xia 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2022年第3期471-480,I0002,共11页
Carbon capture and storage technology have been rapidly developed to reduce the carbon dioxide(CO2)emission into the environment.It has been found that the amine-based organic molecules could absorb CO_(2) efficiently... Carbon capture and storage technology have been rapidly developed to reduce the carbon dioxide(CO2)emission into the environment.It has been found that the amine-based organic molecules could absorb CO_(2) efficiently and form the bicarbonate salts through hydrogen-bond(H-bond)interactions.Recently,the aqueous 1,3-diphenylguanidine(DPG)solution was developed to trap and convert CO_(2) to valuable chemicals under ambient conditions.However,how the DPG molecules interact with CO_(2) in an aqueous solution remains unclear.In this work,we perform molecular dynamics simulations to explore the atomistic details of CO_(2) in the aqueous DPG.The simulated results reveal that the protonated DPGH+and the bicarbonate anions prefer to form complexes through different H-bond patterns.These double H-bonds are quite stable in thermodynamics,as indicated from the accurate density functional theory calculations.This study is helpful to understand the catalytic mechanism of CO_(2) conversion in the aqueous DPG. 展开更多
关键词 CO2 conversion Molecular dynamics simulation Density functional theory calculation Double H-bond 1 3-diphenylguanidine
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First-principles study of lithium intercalated bilayer graphene 被引量:4
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作者 ZHOU JingJing ZHOU WeiWei +5 位作者 GUAN ChunMei SHEN JingQin OUYANG ChuYing LEI MinSheng SHI SiQi TANG WeiHua 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第8期1376-1382,共7页
Litbium intercalated bilayer graphene has been investigated using first-principles density functional theory calculations. Re- sults show that there exist AB and AA stacking sequences for bilayer graphene in which the... Litbium intercalated bilayer graphene has been investigated using first-principles density functional theory calculations. Re- sults show that there exist AB and AA stacking sequences for bilayer graphene in which the latter is more favorable for the Li storage and the former will evolve into the latter with the intercalation of Li ions. The relationship between the interlayer dis- tance of two graphene sheets and the intercalated capacity of Li ions is discussed, It is found that structural defect is identified to store Li ions more favorably than pristine bilayer graphene and an isolated C atom vacancy in bilayer graphene can capture three Li ions between two graphene sheets. 展开更多
关键词 bilayer grapheme lithium ion battery DEFECT first-principles calculation
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Oxygenolysis reaction mechanism of copper-dependent quercetin 2,3-dioxygenase:A density functional theory study
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作者 XIE HuJun LEI QunFang FANG WenJun 《Science China Chemistry》 SCIE EI CAS 2012年第9期1832-1841,共10页
The mechanism of the action of copper-dependent quercetin 2,3-dioxygenase (2,3QD) has been investigated by means of hy- brid density functional theory. The 2,3QD enzyme cleaves the O-heterocycle of a quercetin by in... The mechanism of the action of copper-dependent quercetin 2,3-dioxygenase (2,3QD) has been investigated by means of hy- brid density functional theory. The 2,3QD enzyme cleaves the O-heterocycle of a quercetin by incorporation of both oxygen atoms into the substrate and releases carbon monoxide. The calculations show that dioxygen attack on the copper complex is energetically favorable. The adduct has a possible near-degeneracy of states between [Cu2+-(substrate H+)] and [Cu+-(sub- strate-H). ], and in addition the pyramidalized C2 atom is ideally suited for forming a dioxygembridged structure. In the next step, the C3-C4 bond is cleaved and intermediate lnt5 is formed via transition state TS4. Finally, the Oa-Ob and C2-C3 bonds are cleaved, and CO is released in one concerted transition state (TS5) with the barrier of 63.25 and 61.91 k J/tool in the gas phase and protein environments, respectively. On the basis of our proposed reaction mechanism, this is the rate-limiting step of the whole catalytic cycle and is strongly driven by a relatively large exothermicity of 100.86 kJ/mol. Our work provides some valuable fundamental insights into the behavior of this enzyme. 展开更多
关键词 quercetin 2 3-dioxygenase DFT calculations catalytic mechanism METALLOENZYMES oxygenolysis
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Structural and Interaction Properties of Porphyrin Layers — A Quantum Chemical Study
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作者 G.Praveena A.Abiram 《Communications in Theoretical Physics》 SCIE CAS CSCD 2015年第5期625-634,共10页
This paper is proposed to understand the interaction of porphyrin layers with diatomic molecules interacting at their interior regions by applying ab initio and density functional theory (DFT) methods. We have used ... This paper is proposed to understand the interaction of porphyrin layers with diatomic molecules interacting at their interior regions by applying ab initio and density functional theory (DFT) methods. We have used NO, GO, and O2 diatomic molecules to interact with the porphyrin layers. The most common Fe-centered metalloporphyrin structure with tetra-pyrrlic rings having N4 core is chosen for the study. The optimization of Porphyrin-Porphyrin (PI-PII) and Porphyrin-Diatomic molecule-Porphyrin (P1-AB-P11) (AB = NO, CO, and 02) complexes are performed using HF method. In order to understand the planarity and appropriate stacking size of porphyrins and also to infer the separation of diatomic molecules between porphyrin layers the behavior of PI-AB-PH complexes (where AB = NO, CO, and 02) are analyzed using structural properties and molecular electrostatic potentials (MEP). The MEPs are caiculated using hybrid exchange correlation functional B3PW91 of DFT Mong with 6-31+G basis set for the PI-PH and PI-AB-Pzz complexes obtained from HF method. 展开更多
关键词 PORPHYRIN ab initio density functional theory diatomic molecules molecular storage
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