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Thiolsulfonate functionalized polystyrene resin:Preparation and application in the isolation and identification of electrophilic mutagens 被引量:1
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作者 Wu El Robert M. Carlson 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第12期1520-1527,共8页
A new approach for isolation and identification of elecrtophilic mutagens from complex matrix was developed. Thiosulforfic anion was immobilized onto polystyrene beads and used as separation media. Potassium polystyry... A new approach for isolation and identification of elecrtophilic mutagens from complex matrix was developed. Thiosulforfic anion was immobilized onto polystyrene beads and used as separation media. Potassium polystyryl-thiosulfonate, prepared from polystyryl- sulfonyl chloride and KHS, was observed to selectively react with model electrophilic mutagens such as alkyl halides, ct-chloroketones and α-chloroesters to produce polystyryl-thiosulfonlc esters. After separation from other nonreactive organic compounds, the beads then reacted with ethanethiol to produce unsymmetrical ethyl disulfides which are easily detected by GC/MS. For one mutagenic compound, only one unsymmetrical disulfide was found to contain its structure part. Thus, the structure of the parent mutagens could be deduced from that of the unsymmetrical disulfides. The degree of functionalization of the potassium polystyryl-thiosulfonate resin was 1.11 mmol/g. Its reactivity was discussed and its recycling method was reported here. 展开更多
关键词 functionalized polystyrene potassium polystyryl-thiosulfonate unsymmetrical ethyl disulfides electrophilic mutagens
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Quantitative Electrophilicity Measures
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作者 GONZáLEZ Marco Martínez CáRDENAS Carlos +4 位作者 RODRíGUEZ Juan I. LIU Shubin HEIDAR-ZADEH Farnaz MIRANDA-QUINTANA Ramón Alain AYERS Paul W. 《物理化学学报》 SCIE CAS CSCD 北大核心 2018年第6期662-674,共13页
Quantitative correlation of several theoretical electrophilicity measures over different families of organic compounds are examined relative to the experimental values of Mayr et al.Notably,the ability to predict thes... Quantitative correlation of several theoretical electrophilicity measures over different families of organic compounds are examined relative to the experimental values of Mayr et al.Notably,the ability to predict these values accurately will help to elucidate the reactivity and selectivity trends observed in charge-transfer reactions.A crucial advantage of this theoretical approach is that itprovides this information without the need of experiments,which are often demanding and time-consuming.Here,two different types of electrophilicity measures were analyzed.First,models derived from conceptual density functional theory(c-DFT),including Parr's original proposal and further generalizations of this index,are investigated.For instance,the approaches of Gázquez et al.and Chamorro et al.are considered,whereby it is possible to distinguish between processes in which a molecule gains or loses electrons.Further,we also explored two novel electrophilicity definitions.On one hand,the potential of environmental perturbations to affect electron incorporation into a system is analyzed in terms of recent developments in c-DFT.These studies highlight the importance of considering the molecular surroundings when a consistent description of chemical reactivity is needed.On the other hand,we test a new definition of electrophilicity that is free from inconsistencies(so-called thermodynamic electrophilicity).This approach is based on Parr's pioneering insights,though it corrects issues present in the standard working expression for the calculation of electrophilicity.Additionally,we use machine-learning tools(i.e.,symbolic regression) to identify the models that best fit the experimental values.In this way,the best possible description of the electrophilicity values in terms of different electronic structure quantities is obtained.Overall,this straightforward approach enables one to obtain good correlations between the theoretical and experimental quantities by using the simple,yet powerful,interpretative advantage of c-DFT methods.In general,we observed that the correlations found at the HF/6-31 G(d) level of theory are of semi-quantitative value.To obtain more accurate results,we showed that working with families of compounds with similar functional groups is indispensable. 展开更多
关键词 electrophilicITY CONCEPTUAL density functional theory SYMBOLIC regression GENETIC PROGRAMMING GRAMMATICAL evolution
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Polymer-support Selenium-induced Electrophilic Cyclization:Solid-phase Synthesis of Flavonoids
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作者 Jian CAO E TANG +2 位作者 Xuan HUANG Lu Ling WU Xian HUANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第7期857-858,共2页
The Lewis acid mediated polystyrene supported selenium cyclization of chalcones and oxidative cleavage of selenium resins flavonoids in good yields and purities have been reported. induced intramolecular gave the cor... The Lewis acid mediated polystyrene supported selenium cyclization of chalcones and oxidative cleavage of selenium resins flavonoids in good yields and purities have been reported. induced intramolecular gave the corresponding 展开更多
关键词 FLAVONOIDS selenenyl bromide resin solid-phase synthesis electrophilic cyclization.
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Studies on Electrophilic Substitution of Quasi-Aromatic Metal Ion Complexes
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作者 XIA Xiao-ping, HE Hai-ying and LI Ming (Department of Chemistry, Huazhong University of Science and Technology, Wuhan, 430074)ZHAO Cheng-xue (National Laborotory of Applied Organic Chemistry, Lanzhou University, Lanzhou, 730000) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1993年第4期282-287,共6页
The electrophilic substitution reaction occurring to the chelate ring of the complexes could be regarded as an indication of quasi-aromaticity of the ring systems, no catalyst was used and only triethylamine was emplo... The electrophilic substitution reaction occurring to the chelate ring of the complexes could be regarded as an indication of quasi-aromaticity of the ring systems, no catalyst was used and only triethylamine was employed, implying that the aroylating agents with different p-substituents are polarized enough to be effective electrophiles to attack the methine carbon of the electron-rich substrate 1. This property is probably the clue to polarization of the ligand electrons by the nickel( Ⅱ ) ion and to the participation of the nickel( Ⅱ ) in the π-bond systems of the two coordinated conjugated rings. The linearity relationship between vd-d maxima, E1/2OX(1) and σp are obtained, respectively. The electronic environment of central metal ion as well as the aromaticity of the ring system are affected by the electronic properties of the p-substituents. A comparison of the electrochemical results with each other showed .that when the electronegativity of the substituent was higher, the oxidation(Ni2+/Ni3+) becomes more difficult. 展开更多
关键词 electrophilic substitution Quasi-aromatic metal ions Complex
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Addition of Diphenyldiselenide to Methylenecyclopropanes under Different Conditions: A Good Example for Students to Understand the Differences between Free Radical and Electrophilic Addition Reactions 被引量:2
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作者 Lei Yu Jun Wang Tian Chen Xu Zhang 《教育研究前沿(中英文版)》 2013年第4期134-138,共5页
关键词 硒键 化学键 化学教育 教学方法
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Density Functional Theory Study of Exohedral Carbon Atoms Effect on Electrophilicity of Nicotine: Comparative Analysis
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作者 S. Dheivamalar L. Sugi K. Ambigai 《Computational Chemistry》 2016年第1期17-31,共15页
In recent years, many studies have been done on the structure of fullerene as medicine nano carrier compounds. On this basis, Quantum mechanical calculations have been done and the effect of the nicotine compound in s... In recent years, many studies have been done on the structure of fullerene as medicine nano carrier compounds. On this basis, Quantum mechanical calculations have been done and the effect of the nicotine compound in structure of Nanofullerene C<sub>12</sub> was studied. Density Functional Theory (DFT) can be used to calculate an accurate electronic structure, HOMO and LUMO energies, Mulliken charge of atoms, energetic orbital levels, global hardness, chemical potential and electrophilicity of systems, and finally chemical, physical properties of fullerene and fullerene derivatives. Theoretical calculations such as Natural Bond Orbital (NBO) are very important to understand the pathways of electron transfer in assemblies. Consequently, the obtained results showed that energy orbital levels decreased considerably by linking structure of Nanofullerene to the structure of Nicotine. The intramolecular interaction is formed by the orbital overlap between C-C, C-N, C-H anti bonding orbital which results an intermolecular charge transfer (ICT) from a Lewis valence orbital (donor), with a decreasing of its occupancy, to a non-Lewis orbital (acceptor). The interacting effect is also discussed in terms of the change in the C-C bond lengths, net atomic charge distribution, total dipole moment. The obtained results indicate that the C-C distances are enlarged interaction. Furthermore, there is a complete change in the net atomic charge distribution, as well as a corresponding increase in the value of the total dipole moment. On the basis of fully optimized ground-state structure, TDDFT//B3LYP/3-21G* calculations have been performed to determine the low-lying excited states of nanofullerene interacting with nicotine (NFN). 展开更多
关键词 DFT electrophilicITY Chemical Hardness Chemical Potential Nano Fullerene NICOTINE
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THE PSEUDO ORBITAL STUDIES ON ELECTROPHILIC AROMATIC SUBSTITUTION
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作者 Fu Jiang DING Liang Fu ZHANG Guang Nian LI Chengdu Institute of Organic Chemistry,Academia Sinica,Chengdu 610015 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第1期39-42,共4页
The electrophilic aromatic substitution reactions have been studied by using the con- cept of pseudo orbital proposed by authors,Because the unoccupied orbitals of electrophilic reagents have been.taken into account,t... The electrophilic aromatic substitution reactions have been studied by using the con- cept of pseudo orbital proposed by authors,Because the unoccupied orbitals of electrophilic reagents have been.taken into account,the present results are better than ones given by superdelocalizability,S,. 展开更多
关键词 EHMO THE PSEUDO ORBITAL STUDIES ON electrophilic AROMATIC SUBSTITUTION
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THE ELECTRIC PROPERTY OF SINGLET CARBENE AND ITS ISOELECTRONIC SYSTEM^1——Electrophilic and Nucleophilic Directions of an Atom in the Molecule
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作者 Jing Jiang LIU Lian De LU Department of Chemistry,Nankai University,Tianjin,300071 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第1期9-12,共4页
The electrostatic potential of carbene and nitrene,have been calculated by AB INITIO method with 6-31G** basis set,there are positive potential regions in the directions of vacant P orbitals,and negative regions in th... The electrostatic potential of carbene and nitrene,have been calculated by AB INITIO method with 6-31G** basis set,there are positive potential regions in the directions of vacant P orbitals,and negative regions in the directions of lone-pair electrons. Therefore,atoms in these molecules have different electric properties in different directions.The idea of electrophilic and nucleophilic directions of an atom in molecules should be introduced. 展开更多
关键词 ATOM electrophilic and Nucleophilic Directions of an Atom in the Molecule THE ELECTRIC PROPERTY OF SINGLET CARBENE AND ITS ISOELECTRONIC SYSTEM~1 ITS
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THE RELATIONSHIPS BETWEEN THE POLARIZING FORCE OF CATIONS AND THE ELECTROPHILIC CHARACTER AND CATALYTIC PERFORMANCES OF PROMOTED Pt-Al_2O_3 CATALYST
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作者 Jia LIU Xi Yao YANG Li PANG Department of Chemistry,Peking University,Beijing,100871 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第3期261-262,共2页
The electronic modification effect of various metal oxides over Pt-Al;O;catalyst andthe relationships between the polarizing force of cations(PFC)and the electrophiliccharacter(EC)and catalytic performances(CP)o... The electronic modification effect of various metal oxides over Pt-Al;O;catalyst andthe relationships between the polarizing force of cations(PFC)and the electrophiliccharacter(EC)and catalytic performances(CP)of promoted Pt catalyst have been studiecby competitive hydrogenation reaction method(CHRM)and test reaction,i.e.hydrogena-tion of benzene and hydrogenolysis of cyclopentane. 展开更多
关键词 Pt EC THE RELATIONSHIPS BETWEEN THE POLARIZING FORCE OF CATIONS AND THE electrophilic CHARACTER AND CATALYTIC PERFORMANCES OF PROMOTED Pt-Al2O3 CATALYST Al
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不同取代基对传统烯烃亲电加成反应机制的挑战 被引量:1
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作者 刘永东 王露红 钟儒刚 《山东化工》 CAS 2024年第2期168-170,共3页
氯鎓离子是经典的烯烃与次氯酸亲电加成反应中的重要中间体,经过此中间体的分步反应机制是教学烯烃亲电加成反应中介绍的唯一反应机制。然而,量子化学计算结果表明,烯烃的不同取代基会导致反应机制发生变化。被一般供电基团和弱吸电基... 氯鎓离子是经典的烯烃与次氯酸亲电加成反应中的重要中间体,经过此中间体的分步反应机制是教学烯烃亲电加成反应中介绍的唯一反应机制。然而,量子化学计算结果表明,烯烃的不同取代基会导致反应机制发生变化。被一般供电基团和弱吸电基团取代的烯烃与次氯酸先形成氯鎓离子中间体,再生成马氏产物;而当取代基具有与C=C双键形成p-π或π-π共轭的供电基团时,反应生成的是碳正离子中间体。中和强吸电基团取代的烯烃分别通过协同和亲核加成反应机制与次氯酸反应,生成反马氏产物。由此可见,教学烯烃亲电加成反应机制时,不能局限在传统的氯鎓离子中间体机制,关注机制的适用体系是非常必要的。 展开更多
关键词 亲电加成反应 反应机制 氯鎓离子
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实验室研究等离子体鞘套测量方法和干预技术
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作者 余鹏程 刘宇 +1 位作者 雷久侯 曹金祥 《电波科学学报》 CSCD 北大核心 2024年第1期12-17,共6页
航天飞行器再入大气层时,由于激波加热和热化学防护材料的烧蚀等原因,会在飞行器表面形成致密的等离子体鞘套,从而造成无线电通信信号中断。因此,减轻和消除黑障对飞行器测控安全至关重要。为了解决该难题,本文针对性地发展了适用于等... 航天飞行器再入大气层时,由于激波加热和热化学防护材料的烧蚀等原因,会在飞行器表面形成致密的等离子体鞘套,从而造成无线电通信信号中断。因此,减轻和消除黑障对飞行器测控安全至关重要。为了解决该难题,本文针对性地发展了适用于等离子体鞘套测量的探针设备和主动干预的技术,并利用实验室等离子体进行了验证。首先,提出了一种静电-微波复合探针,基于探针和飞行器表面曲面共形的优势,可以实时、有效地探测黑障高温流场中的电子密度;进一步,发展了亲电子物质释放实验主动干预方法,地面模拟实验表明该方法可以有效地降低流场等离子体中的电子密度。 展开更多
关键词 等离子体 电子密度 流场 亲电子物质 探针
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有机催化3-氨基氧化吲哚与偶氮二羧酸酯的不对称加成反应
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作者 张健 田芳 王立新 《合成化学》 CAS 2024年第2期116-123,共8页
手性3,3-双取代氧化吲哚结构单元广泛存在于具有生物活性的天然产物和具有药物活性的化合物中,尤其存在于具有光学活性的3-氨基氧化吲哚中。此外,手性3,3-双取代氧化吲哚结构单元作为有效抗疟药(NITD609)、高效焦虑和抑郁抑制剂(SSR1494... 手性3,3-双取代氧化吲哚结构单元广泛存在于具有生物活性的天然产物和具有药物活性的化合物中,尤其存在于具有光学活性的3-氨基氧化吲哚中。此外,手性3,3-双取代氧化吲哚结构单元作为有效抗疟药(NITD609)、高效焦虑和抑郁抑制剂(SSR149415)以及HIV蛋白酶抑制剂而备受关注。因此,发展合成手性3-氨基氧化吲哚的新方法具有重要意义。为了实现反应的敏感性产物N,N′-缩靛红衍生物的不对称合成,使用金鸡纳碱衍生的方酰胺作催化剂,3-氨基氧化吲哚席夫碱与偶氮二羧酸酯作模板底物,最终以70%~85%的产率和45%~88%的对映选择性获得相应产物。该反应的实验条件温和,原子经济性高。 展开更多
关键词 N N′-缩靛红 不对称催化 3-氨基氧化吲哚席夫碱 偶氮二羧酸酯 亲电加成
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自组装协同催化高选择性合成卤代芳烃
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作者 史时辉 李皓瑜 +2 位作者 韩少杰 姚一凡 刘思齐 《大学化学》 CAS 2024年第5期336-344,共9页
卤代芳烃是非常重要的合成砌块,广泛应用于农用化学品、材料和药物等的合成。芳烃的亲电取代卤化反应是制备芳基卤化物最简单的方法,但是富电子芳烃的卤化反应存在区域选择性差的挑战。本实验采用自组装协同催化策略,以环己基苯溴化反... 卤代芳烃是非常重要的合成砌块,广泛应用于农用化学品、材料和药物等的合成。芳烃的亲电取代卤化反应是制备芳基卤化物最简单的方法,但是富电子芳烃的卤化反应存在区域选择性差的挑战。本实验采用自组装协同催化策略,以环己基苯溴化反应为模型反应,高选择性合成溴代芳烃,进而应用于卤代芳烃的高选择性合成。在加深学生芳烃亲电取代卤化反应的同时,也向学生传授自组装、协同催化和路易斯酸碱催化等重要知识,加深学生对亲电取代反应机理和离子型中间体的了解。实验主要由卤代芳烃的合成、机理探究及实验普适性三部分组成,包含多种有机实验基本操作,涉及反应监测、分离纯化、产物表征等多个重要环节,实验整体时长7小时,安全性高,可操作性强,适合本科实验教学开设。本实验秉持科研反哺教学的理念,将新的科研成果转化为人才培养内容,有助于提高学生的科研创新与实践能力。 展开更多
关键词 卤代芳烃 区域选择性 亲电取代卤化反应 协同催化
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芘并硼氮杂菲的合成、结构及光物理性质研究
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作者 郝玉银 蒋震 刘志强 《合成化学》 CAS 2024年第11期992-999,共8页
近年来,硼氮杂稠环芳烃在有机光电功能材料领域展现出巨大潜力,但是对于具有大共轭结构的硼氮杂稠环芳烃的合成与性质研究仍然有待深入。本文报道了基于胺基前体硼化反应路线合成2个芘并硼氮杂菲化合物并开展的光物理性质研究,合成路线... 近年来,硼氮杂稠环芳烃在有机光电功能材料领域展现出巨大潜力,但是对于具有大共轭结构的硼氮杂稠环芳烃的合成与性质研究仍然有待深入。本文报道了基于胺基前体硼化反应路线合成2个芘并硼氮杂菲化合物并开展的光物理性质研究,合成路线简单,一锅反应最多同时新形成4个化学键。研究表明:1-BN-2-Na-Py和2-BN-1-Na-Py具有高荧光量子产率(0.46,0.70)和双光子吸收截面(230 GM以上)。X-射线单晶衍射解析了2-BN-1-Na-Py的单晶结构,表明2-BN-1-Na-Py分子优良的平面性,确证了B—N键具有部分双键特征。通过密度泛函理论(DFT)计算表明:硼嗪单元(BNC4环)具有一定的芳香性(NICS(1)值为-4.923,-1.935),解释了B—N键的引入对化合物电子结构的影响。 展开更多
关键词 硼嗪 硼氮杂菲 多环芳烃 单晶结构 亲电硼化
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S-(1,3-Dioxoisoindolin-2-yl)O,O-diethyl phosphorothioate (SDDP): A practical electrophilic reagent for the phosphorothiolation of electron-rich compounds
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作者 Ze-Yuan Ma Mei Xiao +2 位作者 Cheng-Kun Li Adedamola Shoberu Jian-Ping Zou 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第5期151-154,共4页
An efficient synthesis of the electrophilic reagent,S-(1,3-dioxoisoindolin-2-yl)O,O-diethyl phosphorothioate(SDDP)is described.Moreover,the synthetic applications of SDDP wherein the transfer of the SP(O)(OEt)_(2) moi... An efficient synthesis of the electrophilic reagent,S-(1,3-dioxoisoindolin-2-yl)O,O-diethyl phosphorothioate(SDDP)is described.Moreover,the synthetic applications of SDDP wherein the transfer of the SP(O)(OEt)_(2) moiety occurs were investigated.In this manner,SDDP underwent facile SP(O)(OEt)_(2) transfer with electron-rich substrates such as ketones,indoles,and thiols to formα-phosphorothiolated ketones,3-phosphorothiolated indoles and S-phosphorothiolated thioethers,respectively. 展开更多
关键词 electrophilic reagent Phosphorothiolation electrophilic substitution
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Enriched electrophilic oxygen species facilitate acidic oxygen evolution on Ru-Mo binary oxide catalysts
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作者 Yaya Wang Yunzhou Wen +10 位作者 Yumeng Cheng Xinhong Chen Mengjiao Zhuansun Tongbao Wang Jun Li Debora Meira Huarui Sun Jun Wei Jia Zhou Yuhang Wang Sisi He 《Nano Research》 SCIE EI CSCD 2024年第3期1165-1172,共8页
The polymer electrolyte membrane(PEM)electrolyzers are burdened with costly iridium(Ir)-based catalysts and high operation overpotentials for the oxygen evolution reaction(OER).The development of earth-abundant,highly... The polymer electrolyte membrane(PEM)electrolyzers are burdened with costly iridium(Ir)-based catalysts and high operation overpotentials for the oxygen evolution reaction(OER).The development of earth-abundant,highly active,and durable electrocatalysts to replace Ir is a critical step in reducing the cost of green hydrogen production.Here we develop a Ru5Mo4Ox binary oxide catalyst that exhibits high activity and stability in acidic OER.The electron-withdrawing property of Mo enriches the electrophilic surface oxygen species,which promotes acidic OER to proceed via the adsorbate evolution pathway.As a result,we achieve a 189 mV overpotential at 10 mA·cm^(-2) and a Tafel slope of 48.8 mV·dec^(-1).Our catalyst demonstrates a substantial 18-fold increase in intrinsic activity,as evaluated by turnover frequency,compared to commercially available RuO_(2) and IrO_(2) catalysts.Moreover,we report a stable OER operation at 10 mA·cm^(-2) for 100 h with a low degradation rate of 2.05 mV·h^(-1). 展开更多
关键词 ELECTROCATALYSIS oxygen evolution reaction(OER) ruthenium(Ru)-based oxide molybdenum electrophilic oxygen
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Prediction of the Photofading of Selected Derivatives of 5-(4-X-Phenylazo)-3-Cyano-1-(H or Ethyl)-6-Hydroxy-4-Methyl-2-Pyridone: Theoretical Studies, Comparison of AM1 and PM3 Methods
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作者 Krzysztof Wojciechowski Lucjan Szuster 《Computational Chemistry》 CAS 2024年第2期25-56,共32页
We analysed the photooxidation reaction in the electro-(1O2) and nucleophilic (O2•−) reaction of 2-pyridone azo derivatives. First, we calculated the energy (enthalpies) of tautomers formation, which is a measure of d... We analysed the photooxidation reaction in the electro-(1O2) and nucleophilic (O2•−) reaction of 2-pyridone azo derivatives. First, we calculated the energy (enthalpies) of tautomers formation, which is a measure of durability and the probability of their formation. We performed the light fastness calculations of the monoazopyridone dyes. Using the semi-empirical methods of quantum chemistry AM1 and PM3, the reactivity indicators of superdelocalisability (SrE(N)) and the electron density distribution in ground state on the highest occupied HOMO orbital and the lowest unoccupied excited state LUMO in 2-pyridone phenylazo derivatives were calculated. Superdelocalisability coefficients enable the stability to oxidising agents of various chemical molecules depending on the tautomeric forms in which they may occur. The results of the electron density calculations at the HOMO and LUMO boundary orbitals allow to determine the tendency to electrophilic attack with singlet oxygen 1O2 or nucleophilic attack of the superoxide anion O2•−on a specific atom in the molecule. The structure of the dyes was optimised with MM+, MD and AM1 or PM3 until a constant energy value was achieved with a convergence criterion of 0.01 kcal/mol. 展开更多
关键词 Photochemical Degradation AM1 and PM3 Methods Boundary Orbitals Electron Densities electrophilic and Nucleophilic Reaction HOMO and LUMO Orbitals
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基于亲电/亲核反应描述符的气体介质绝缘强度预测
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作者 夏涵怡 杨帅 +3 位作者 汪雪逸 张闹闹 刘关平 肖集雄 《原子与分子物理学报》 CAS 北大核心 2024年第2期45-54,共10页
研究分子微观参数与气体介质绝缘强度的关联,可为SF_(6)替代气体筛选提供方向.本文基于密度泛函理论,采用M06-2X泛函与def2系列基组,计算了73种气体分子的亲电/亲核反应描述符,包括轨道能量参数、概念密度泛函理论的参数、不同电子概率... 研究分子微观参数与气体介质绝缘强度的关联,可为SF_(6)替代气体筛选提供方向.本文基于密度泛函理论,采用M06-2X泛函与def2系列基组,计算了73种气体分子的亲电/亲核反应描述符,包括轨道能量参数、概念密度泛函理论的参数、不同电子概率密度等值面的静电势参数等;分析了各描述符与气体介质绝缘强度的相关性,以及描述符的独立性,最终提出了绝缘强度预测模型.最低空轨道能量、正负静电势表面积、静电势平均偏差、简缩局部亲电指数最小值与绝缘强度相关性较强,且彼此间相关性较低.预测模型在电子概率密度0.0002 a.u.时精度最优,其可决系数R^(2)为0.809,均方误差MSE为0.096. 展开更多
关键词 绝缘强度 亲电反应 亲核反应 构效关系
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金属羰基化合物参与催化反应的研究进展
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作者 林庭志 徐欣阳 +3 位作者 沈旭涛 张东钊 徐云东 胡蔚然 《南京工业大学学报(自然科学版)》 CAS 北大核心 2024年第2期119-130,共12页
在有机化学中,同时具备亲电中心和亲核中心的化合物一直是科研工作者的重点研究对象,而金属羰基化合物M-homoenolate(M为金属)在这类化合物中最具代表性,它可以作为一种碳亲核试剂与亲电试剂发生作用,实现羰基β位的碳碳键/碳杂键的偶... 在有机化学中,同时具备亲电中心和亲核中心的化合物一直是科研工作者的重点研究对象,而金属羰基化合物M-homoenolate(M为金属)在这类化合物中最具代表性,它可以作为一种碳亲核试剂与亲电试剂发生作用,实现羰基β位的碳碳键/碳杂键的偶联反应。由于羰基官能团广泛存在于醛类、酮类、酯类、酸酐类等化合物中,因此,对M-homoenolate的探索极具科学研究价值与市场应用价值;同时,它更是一类广泛应用于药物化学和天然分子合成中的中间体。 展开更多
关键词 Homoenolate化学 金属羰基化合物 碳亲核试剂与亲电试剂
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新型生物膜载体在污水处理中的研究现状
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作者 刘亚雯 贾方旭 +3 位作者 贾非睿 刘晨雨 赵星程 姚宏 《化工进展》 EI CAS CSCD 北大核心 2024年第10期5805-5819,共15页
生物处理法是污水处理领域的核心技术,其中的生物膜法因具有耐冲击负荷、污泥产量少、运行管理方便等优势,已在全球范围内得到广泛关注。生物膜载体作为微生物附着生长材料,在生物膜处理工艺中起到关键作用,直接影响工艺的处理效果。然... 生物处理法是污水处理领域的核心技术,其中的生物膜法因具有耐冲击负荷、污泥产量少、运行管理方便等优势,已在全球范围内得到广泛关注。生物膜载体作为微生物附着生长材料,在生物膜处理工艺中起到关键作用,直接影响工艺的处理效果。然而,目前所开发的生物膜载体大多只能为微生物提供适宜稳定的生态位,并不具有强化污水处理效果的能力。为此,本文围绕五种能够提高污染物降解效率的新型生物膜载体(缓释生物膜载体、氧化还原介体生物膜载体、磁性生物膜载体、亲水改性生物膜载体、亲电改性生物膜载体)进行讨论,详细阐述了其具体分类与作用机理,并针对其今后研究方向与未来发展提出建设性建议,以期为未来大范围提标改造污水处理厂提供理论参考。 展开更多
关键词 新型生物膜载体 缓释生物膜载体 氧化还原介体生物膜载体 磁性生物膜载体 亲水改性生物膜载体 亲电改性生物膜载体
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