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Theoretical Study on the Dissociation of Ligands in the Rhodium and Iridium Complexes Containing 1,1,1,5,5,5-Hexafl uo roacetylaceto nato

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Chinese Journal of Chemistry 2013年第3期31卷 421-429页

作者： xiufang ma Yanhua Lei Zhaoxu Chen Institute of Theoretical and Computational Chemistry Key Laboratory of Mesoscopic Chemistry of MOE School of Chemistry and Chemical Engineering Nanjing University Nanjing Jiangsu 210093 China Institute of Molecular Engineering and Applied Chemistry Anhui University of Technology Ma' anshan Anhui 243002 China

Functionalization of the inert C-H bonds of unsaturated molecules by transition metal complex is an important means to form new C-C bonds. The functionalization is usually initiated by the ligand dissociation of a complex. In this paper we employ both ab initio and density functional methods to explore the influence of central metals, conformation, solvent and protonation on the ligand dissociation of the （hfac-O,O）2M（L）（py） complexes [M=Rh（Ⅲ） or Ir（Ⅲ）, hfac-O,O=k^2-O,O-1,1,1,5,5,5-hexafluoroacetylacetonato, L = CH3, CH3CO2, （CH3CO）2CH, CH30 or OH, py=pyridine]. We demonstrate that ligand pyridine dissociates more easily than the ＂L＂ ligands un-der study in aprotic solvent and gas phase and the dissociation of pyridine is more facile in the trans-conformation than in the cis-isomer. These phenomena are rationalized based on electronic structure and molecular orbital inter-actions. We show that solvation only slightly stabilizes the complexes and does not change the ligand dissociation ordering. In particular, we show that pyridine is no longer the labile ligand in protic media. Instead, the oxy-gen-containing ligands （apart from those like hfac that form a cyclic structure with the central metal） that coordinate to the central metal via oxygen atom become the labile ones. Finally our calculations indicate that hfac is a stable ligand, even in protic media.

关键词： C-H activation protonation conformatiom bond dissociation energy

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教育强国的数字化特征、关键指标与发展路向

电化教育研究 2024年第2期45卷 5-12页

作者：柯清超鲍婷婷马秀芳房静仪华南师范大学教育信息技术学院广东广州510631

国家将教育数字化作为教育强国建设的重要内容进行专门部署,强调教育数字化是开辟教育发展新赛道和塑造教育发展新优势的重要突破口。为了明晰教育数字化对我国教育强国建设的深远意义和影响,以及推进教育数字化转型与创新的现实路径,... 详细信息

国家将教育数字化作为教育强国建设的重要内容进行专门部署,强调教育数字化是开辟教育发展新赛道和塑造教育发展新优势的重要突破口。为了明晰教育数字化对我国教育强国建设的深远意义和影响,以及推进教育数字化转型与创新的现实路径,文章首先通过文献研究梳理了世界教育强国教育数字化发展的共同特征,总结了我国教育数字化转型面临的问题与挑战。其次,通过引入“教育硬实力”和“教育软实力”的理论分析框架,从过程与状态的双重视角构建了衡量数字化发展的表现性关键指标,为教育数字化助力实现教育强国目标锚定了重点方向。最后,立足当前我国教育强国建设背景下数字化的发展进程与现实挑战,提出发展对策:打造世界一流的教育数字基座、形成中国特色的数字教育思想、构建影响世界的数字教育生态、完善数字教育公共服务体系、加强数字化全民终身学习体系与推动数字教育产业集群纵深发展。

关键词：教育强国教育数字化数字教育教育新基建教育数字基座

国家中小学智慧教育平台教师持续使用意愿影响因素研究

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中国电化教育 2024年第10期 68-75,93页

作者：马秀芳黄正华米桥伟柯清超华南师范大学教育信息技术学院广东广州510631 中国教育科学研究院荔湾实验学校广东广州510145

国家中小学智慧教育平台的可持续发展依赖于教师的持续使用。探究影响中小学教师持续使用该平台意愿的因素,有助于优化和改进平台,推动其深度应用。该文基于信息系统持续理论、信息系统成功理论、自我效能感理论和社会影响理论,构建了... 详细信息

国家中小学智慧教育平台的可持续发展依赖于教师的持续使用。探究影响中小学教师持续使用该平台意愿的因素,有助于优化和改进平台,推动其深度应用。该文基于信息系统持续理论、信息系统成功理论、自我效能感理论和社会影响理论,构建了影响教师持续使用国家智慧教育平台意愿的整合模型。通过结构方程模型(SEM)和人工神经网络(ANN)对35934份中小学教师问卷数据进行分析,挖掘出影响教师持续使用平台的关键因素及其结构关系,并揭示各因素的相对重要性。研究结果表明,教师对平台的持续使用意愿在地域、年龄和任教学段上存在差异;满意度是影响教师持续使用意愿的关键因素,社会影响因素的作用略高于教师的数字素养水平;资源优质、功能易用和教学适切是维持教师持续使用意愿的重要基础;感知有用性和期望确认度在满意度形成机制中占核心地位,资源质量是影响期望确认度的关键因素。基于研究发现该文给出了提升教师使用平台意愿、促进平台可持续发展的实践建议。

关键词：国家中小学智慧教育平台数字教育资源持续使用意愿感知有用性教师数字素养

First-principles calculation of core-level binding energy shift in surface chemical processes

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Science China Chemistry 2010年第2期53卷 402-410页

作者： ZENG ZhenHua ma xiufang DING WuChen LI WeiXue State Key Laboratory of Catalysis and Center for Theoretical and Computational Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Combined with third generation synchrotron radiation light sources, X-ray photoelectron spectroscopy (XPS) with higher energy resolution, brilliance, enhanced surface sensitivity and photoemission cross section in real time found extensive applications in solid-gas interface chemistry. This paper reports the calculation of the core-level binding energy shifts (CLS) using the first-principles density functional theory. The interplay between the CLS calculations and XPS measurements to uncover the structures, adsorption sites and chemical reactions in complex surface chemical processes are highlight. Its application on clean low index (111) and vicinal transition metal surfaces, molecular adsorption in terms of sites and configuration, and reaction kinetics are domonstrated.

关键词： first principles core-level binding energy shift surface chemical processes

Construction Direction and Development Path of Digital Educational Resources in the Era of New Educational Infrastructure Construction

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Frontiers of Education in China 2022年第4期17卷 510-531页

作者： KE Qingchao LIN Jian ma xiufang BAO Tingting School of Information Technology in Education South China Normal UniversityGuangzhou 510631China

Digital educational resources have become essential elements of modern educational public ***’s national program on new educational infrastructure construction has proposed to take new infrastructure construction of digital educational resources as one of the critical *** paper aims to provide a theoretical basis for advancing the reform and development of digital educational resources in the new *** classifies the current development and realistic challenges of China’s digital educational resources,and summaries and interprets the directions of the three construction projects of new type resources and tools,the resource supply system,and the resource supervisory *** depicts the prospect of digital educational resource construction in the intelligent era in the combination of the strategic layout of the policies on new educational infrastructure *** also discusses such key technologies supporting new infrastructure construction of digital educational resources as multimodal learning analytics,disciplinary knowledge graphs,machine learning,and *** finally proposes a specific development path for new infrastructure construction of digital educational resources.

关键词： new educational infrastructure construction digital educational resources disciplinary knowledge graph resource supply system

The First-principles Study on the Occupation Behavior and the Ductility Mechanism of Zr in Ni-Ni_3Al System with Lattice Misfit

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Journal of materials Science & Technology 2014年第5期30卷 517-522页

作者： Yuxi Wu Wanglin Zhang Jia Guo Jieshan Hou Xiuyan Li Renzhong Huang xiufang ma Qianfeng Zhang Institute of Molecular Engineering and Applied Chemistry Anhui University of Technology Shenyang National Laboratory for materials Science Institute of Metal ResearchChinese Academy of Sciences College of Physics Science and Technology Shenyang Normal University

The influence of lattice misfit on the occupation behavior and the ductility effect of Zr in Ni-Ni3Al alloys were explored. It is found in energy analysis that the preferable site of Zr between Ni sublattice and Al sublattice will change under different lattice misfit, however, the Zr prefers to segregate Ni phase rather than Ni3Al phase in all lattice misfit range, which makes it impossible for Zr to go into Ni3Al phase to occupy Al sublattice in Ni-Ni3Al system. Bond order （BO） analysis shows that the localized ductility effect of Zr differs in different region, and the comparison between Zr-free and Zr-doped BO analysis successfully explain the mechanism of the embrittlement of Ni-Ni3Al alloys and the ductility effect of Zr.

关键词： Zirconium Lattice misfit Occupation behavior Ductility Embrittlement

High-Performance Energetic Characteristics and magnetic Properties of a Bifunctional Azido-Cobalt(Ⅱ) Compound

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High-Performance Energetic Characteristics and Magnetic Prop...

中国化学会第十九届全国化学热力学和热分析学术会议

作者： Xiaohui ma xiufang ma Fengqin An Weiming Song Xiangyu Liu College of Chemistry and Chemical Engineering Ningxia University

A novel one-dimensional azido-cobalt(Ⅱ) compound,[Co(1-mbt)(N)](1)(where 1-mbt is the 1-((2-propyl-imidazol-1-yl)methyl)-benzo[1,2,3]triazole),has been hydrothermally synthesized.X-ray crystal structure analysis demonstrates that two crystallographically independent Co(Ⅱ) atoms in the asymmetrical unit of compound 1 exhibit rectangular pyramid *** 3 D supermolecular network of 1 consists of well-isolated 1 D metal chains in which the azido bridging ligands take on an unusual new type of combination with the Co(Ⅱ) center as the sign of [-EO-EO-EO-EE-].The different coordination modes of azido anion have resulted different magnetic-exchanges between adjacent Co(Ⅱ) ***-to-end(EE) mode mediates antiferromagnetic(AF) coupling,whereas the end-on(EO) mode contributes to ferromagnetic(F) *** magnetic susceptibility measurements reveal that 1 displays typical slow relaxation of single-chain magnet(SCM).Density functional theory(DFT) calculations are performed to offer a qualitative theoretical explanation of the magnetic *** studies show that the resulting compound acts out superior detonation properties,insensitiveness,and thermostability due to the high nitrogen content(N = 40.10%) and coherent intrachain *** thermal decomposition kinetics of 1 is studied by Kissinger’s method and Ozawa’s *** that 1 provides with potential application prospect as a new generation of environmentally friendly explosive owning to the oxygen-poor *** addition,the compound is explored as additives to promote the thermal decomposition of ammonium perchlorate(AP) and hexahydro-1,3,5-trinitro-1,3,5-triazine(RDX).

关键词： azido-Co(Ⅱ) single-chain magnet high-energy materials

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社会化网络环境下的MOOC课程设计

中国电化教育 2015年第12期 59-64页

作者：马秀芳华南师范大学教育信息技术学院广东广州510631

随着社会化网络的发展和普及,社会化网络环境以其社会性、开放性、聚合性、互动性等特点,为MOOC的设计和开发提供了新途径。该文分析了社会化网络环境下MOOC设计的要素和基本模式,并通过个案研究,从课程设计流程、课程目标、课程环境、... 详细信息

随着社会化网络的发展和普及,社会化网络环境以其社会性、开放性、聚合性、互动性等特点,为MOOC的设计和开发提供了新途径。该文分析了社会化网络环境下MOOC设计的要素和基本模式,并通过个案研究,从课程设计流程、课程目标、课程环境、课程内容、教学活动、课程评价、课程实施等多个角度探索社会化网络环境与MOOC整合的途径与方法,为MOOC设计提供新的视角。

关键词：社会化网络环境 MOOC 课程设计

Impact of copy number of distinct SV40PolyA segments on expression of a GFP reporter gene

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Science China(Life Sciences) 2010年第5期53卷 606-612页

作者： YIN Kang,WANG xiufang,ma Huan,XIE Ying,FENG JingJing,YANG QinQing & Lü ZhanJun Hebei Key Lab of Laboratory Animal,Department of Genetics,Hebei Medical University,Shijiazhuang 050017,China Hebei Key Lab of Laboratory Animal Department of Genetics Hebei Medical University Shijiazhuang China

The presence of Alu repeats downregulates the expression of the green fluorescent protein(GFP) *** found that SV40PolyA(PolyA,240 bp),in either orientation,eliminated the inhibition of GFP gene expression induced by Alu repeats when it was placed between the GFP gene and the Alu *** this study,4 different segments(each 60 bp) were amplified from antisense PolyA(PolyAas) by PCR,and inserted upstream of Alu14 in pAlu14 plasmid(14 Alu repeats inserted downstream of the GFP gene in vector pEGFP-C1 in a head-tail tandem manner).Segments 1F1R(the first 60 bp segment at the 5' end of PolyAas) and 4F4R(the fourth 60 bp segment from the 5' end of PolyAas) did not activate GFP gene expression,whereas 2F2R and 3F3R(the middle two segments) did(as detected by Northern blot analysis and fluorescent microscopy).Different copy numbers of 2F2R and 3F3R segments,in a head and tail tandem manner,were inserted downstream of the GFP gene in pAlu14.p2F2R*4-Alu28,p3F3R*4-Alu18 and p3F3R*4-Alu28 were used as length controls to verify that the decrease in the expression of GFP was not due to the increased length of the inserted segment in the expression *** found that 2 and 4 copies of 2F2R or 3F3R activated the GFP gene more strongly than one copy of ***,more than 8 copies of 2F2R or 3F3R reduced the activation of the GFP *** concluded that SV40PolyAas contained at least two gene-activating elements(2F2R and 3F3R) and 2-4 copies of 2F2R or 3F3R were optimal for the expression of the GFP gene.

关键词： copy number SV40PolyA repeat sequence GFP Alu