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中国化学:英文版 2015年第4期33卷 418-424页

作者： Junhua Li daming du School of Chemical Engineering and Environment Beijing Institute of TechnologyBeijing 100081China

Enantioselective synthesis of biologically active dihydropyrano[2,3-c]pyrazoles has been achieved through a squaramide-catalysed Michael addition/Thorpe-Ziegler type cyclization cascade reaction between arylidenepyra-zolones and malononitrile.A series of optically active dihydropyano[2,3-c]pyrazoles were obtained in excellent yields(up to 99%)and moderate to good enantioselectivities(up to 79%ee)under mild reaction conditions.

关键词： organocatalysis squaramide heterocycles Michael addition cyclization

Enantioselective Construction of Functionalized Thiochromans via Squaramide-Catalyzed Asymmetric Cascade Sulfa-Michael/Michael Addition

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Chinese Journal of Chemistry 2014年第9期32卷 853-858页

作者： Yi Yang daming du School of Chemical Engineering and Environment Beijing Institute of TechnologyBeijing 100081China

An efficient enantioselective cascade sulfa-Michael/Michael addition reaction of trans-3-(2-mercaptophenyl)-2-propenoic acid ethyl ester with nitroalkenes catalyzed by a chiral squaramide catalyst was *** cascade reaction afforded thiochroman derivatives with three contiguous stereocenters in high yields(up to 94%),excellent diastereoselectivities(up to>25∶1 dr)and enantioselectivities(up to 99% ee).

关键词： organocatalysis squaramide Michael addition thiochromans cascade

Modification of diphenylamine-linked bis(oxazoline) ligands: Tuning of electronic effect and rigidity of ligand skeleton

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Science China Chemistry 2009年第9期52卷 1321-1330页

作者： LIU Han LI Wei du daming Beijing National Laboratory for Molecular Sciences(BNLMS) and Key Laboratory of Bioorganic Chemistry and Molecular EngineeringCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China School of Chemical Engineering and Environment Beijing Institute of TechnologyBeijing 100081China

The electronic effect of diphenylamine-linked bis(oxazoline) ligands was tuned through introduction of electron-withdrawing bromo and nitro substituents onto the 4 and 4′ position. The variation of the NH bond acidity was determined by the different chemical shifts of NH. The catalytic activity and enantioselectivity of the modified ligands were tested in the asymmetric Friedel-Crafts alkylation of indole with β-nitrostyrene. The effect of ligand skeleton rigidity was also investigated through the synthesis of iminodibenzyl-linked bis(oxazoline) ligands and evaluation of their catalytic activity in Friedel-Crafts alkylation.

关键词： asymmetric catalysis electronic effect bis(oxazoline) Friedel-Crafts alkylation

方酰胺催化的不对称串联反应合成螺环氧吲哚衍生物研究进展

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有机化学 2020年第10期40卷 3214-3236页

作者：林晔杜大明北京理工大学化学与化工学院北京100081

手性螺环氧吲哚广泛存在于各种生物碱天然产物和药理活性剂中,因此越来越多的有机化学和药物化学研究者投身于构建螺环氧吲哚的优良合成方法.近年来,手性双功能方酰胺催化氧吲哚或者氧吲哚衍生物的不对称串联反应已经成为构建手性螺环... 详细信息

手性螺环氧吲哚广泛存在于各种生物碱天然产物和药理活性剂中,因此越来越多的有机化学和药物化学研究者投身于构建螺环氧吲哚的优良合成方法.近年来,手性双功能方酰胺催化氧吲哚或者氧吲哚衍生物的不对称串联反应已经成为构建手性螺环氧吲哚的有效合成方法.综述了自2015年以来手性双功能方酰胺催化的不对称串联反应合成螺环氧吲哚衍生物的研究进展,并根据不同的催化反应类型进行分类讨论.

关键词：螺环氧吲哚不对称有机催化方酰胺串联反应

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催化不对称Michael加成反应的新进展

有机化学 2002年第3期22卷 164-173页

作者：杜大明花文廷北京大学化学与分子工程学院生命有机与分子工程教育部重点实验室北京100871

总结了近年催化不对称Michael加成反应的新方法 ,包括手性金属络合物催化的反应 ,呈手性Lewis酸性的手性金属络合物促进的不对称加成。

关键词： Michael加成不对称合成催化反应对映选择性手性金属络合物共轭加成手性冠醚络合物

Enhancing ionic conductivity of garnet-type Nb-doped Li_(7)La_(3)Zr_(2)O_(12)by cerium doping

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Journal of Rare Earths 2024年第9期42卷 1740-1746,I0004页

作者： daming Liu Yuan Hou Chaoke Bulin Ruichao Zhao Bangwen Zhang Analytical and Testing Center Inner Mongolia University of Science and TechnologyBaotou014010China School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou014010China School of Metallurgy and Materials Engineering Chongqing University of Science and TechnologyChongqing401331China

We investigated the effect of additional doping with Ce on the ionic conductivity of the Nb-doped Li_(7)La_(3)Zr_(2)O_(12)(LLZO)garnet ceramics using a combination of experimental and modeling *** results indicate that Ce doping can alter lattice parameters of the LLZNO,leading to the enhanced lithium ionic *** Ce,Nb co-doped LLZO(LLZNCO)structure with composition Li_(6.5)La_(3)Zr_(1.5-x)Nb_(0.5)Ce_(x)O_(12)(x=0.125)exhibits a lower activation energy(E_(a)=0.39 eV)than Li_(6.5)La_(3)Zr_(1.5)Nb_(0.5)O_(12)(LLZNO)(E_(a)=0.41 eV).Furthermore,Ce doping leads to an increase in Li~+conductivity from 6.4×10^(-4)to 7×10^(-4)S/cm at room *** addition,we discuss the diffusivity and conductivity of our samples using ab initio molecular dynamics simulations and propose possible mechanisms to explain the enhanced Li-ion conductivity caused by co-doping with Ce and *** results demonstrate that the LLZNCO ceramics are promising candidates for potential solid-state electrolytes for Li-ion batteries.

关键词： Rare earths Solid state electrolyte Ionic conductivity Doping

Effect of Grinding and Polishing on the Residual Stress and Bending Strength of a Silicon Nitride Ceramic

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Journal of Wuhan University of Technology(Materials Science) 2005年第1期20卷 46-48页

作者：高玲 State Key Lab of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

The residual stresses on the surface of the d ifferently ground and polished silicon nitride ceramics were measured using X-r ay diffraction and identified by *** effect of the residual stress on the be nding strength was *** investigations show that the grinding proces s can introduce subatantial tensile residual stresses up to 290MPa on the surfac e of silicon nitride ceramics,which has a significant effect on reducing the ben ding strength of the ceramics after ***,in comparison with the ceramic s with a rough surface,the ceramics with a mirror image surface may have a lower *** can smooth the residual *** we evaluate the qualit y of the ceramic components after grinding,we must take residual stress into con sideration. The grinding methods and grinding conditions must be carefully selec ted in order to get the favorite residual stress as well as the surface smoothne ss.

关键词： residual stress grinding bending strengt h ceramics

Hydrologic Response to Future Climate Change in the dulong-Irra-waddy River Basin Based on Coupled Model Intercomparison Project 6

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Chinese Geographical Science 2024年第2期34卷 294-310页

作者： XU Ziyue MA Kai YUAN Xu HE daming Institute of International Rivers and Eco-security Yunnan UniversityKunming 650500China Yunnan Key Laboratory of International Rivers and Transboundary Eco-security Kunming 650500China

Within the context of the Belt and Road Initiative(BRI)and the China-Myanmar Economic Corridor(CMEC),the dulong-Ir-rawaddy(Ayeyarwady)River,an international river among China,India and Myanmar,plays a significant role as both a valuable hydro-power resource and an essential ecological ***,the water resources and security exhibit a high degree of vulnerabil-ity to climate change *** research evaluates climate impacts on the hydrology of the dulong-Irrawaddy River Basin(DIRB)by using a physical-based hydrologic *** crafted future climate scenarios using the three latest global climate models(GCMs)from Coupled Model Intercomparison Project 6(CMIP6)under two shared socioeconomic pathways(SSP2-4.5 and SSP5-8.5)for the near(2025-2049),mid(2050-2074),and far future(2075-2099).The regional model using MIKE SHE based on historical hydrologic processes was developed to further project future streamflow,demonstrating reliable performance in streamflow simulations with a val-idation Nash-Sutcliffe Efficiency(NSE)of *** showed that climate change projections showed increases in the annual precip-itation and potential evapotranspiration(PET),with precipitation increasing by 11.3%and 26.1%,and PET increasing by 3.2%and 4.9%,respectively,by the end of the century under SSP2-4.5 and *** changes are projected to result in increased annual streamflow at all stations,notably at the basin’s outlet(Pyay station)compared to the baseline period(with an increase of 16.1%and 37.0%at the end of the 21st century under SSP2-4.5 and SSP5-8.5,respectively).Seasonal analysis for Pyay station forecasts an in-crease in dry-season streamflow by 31.3%-48.9%and 22.5%-76.3%under SSP2-4.5 and SSP5-8.5,respectively,and an increase in wet-season streamflow by 5.8%-12.6%and 2.8%-33.3%,***,the magnitude and frequency of flood events are pre-dicted to escalate,potentially impacting hydropower production and food security *** res

关键词： climate change hydrologic response Coupled Model Intercomparison Project 6(CMIP6) MIKE SHE(Système Hydrologique Europeén) dulong-Irrawaddy River Basin

离子液体介质中有机合成及不对称催化反应研究新进展

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有机化学 2003年第4期23卷 331-343页

作者：杜大明陈晓花文廷北京大学化学与分子工程学院

总结了近年离子液体中有机合成反应及不对称催化反应研究新进展 ,包括还原反应、氧化反应、Friedel Crafts反应、Diels Alder反应、交叉偶联反应、加成反应、环缩合反应、自由基反应、Witting反应、重排反应。

关键词：离子液体介质有机合成不对称催化还原反应氧化反应交叉偶联反应加成反应环缩合反应

温和条件下[2-氨基-3-(苯并噻唑-2-基)-4H-色烯-4-基]膦酸酯衍生物的简便合成

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有机化学 2016年第7期36卷 1643-1652页

作者：颜浩浩赵博良高钰杜大明北京理工大学化工与环境学院北京100081

含有不同取代基的(E)-2-(苯并噻唑-2-基)-3-(2-羟基苯基)丙烯腈与亚磷酸二苯酯在水中,无催化剂催化即可发生Michael加环/环化串联反应,可以高产率地生成相应的[2-氨基-3-(苯并噻唑-2-基)-4H-色烯-4-基]膦酸酯衍生物.同时,也尝试了水杨醛... 详细信息

含有不同取代基的(E)-2-(苯并噻唑-2-基)-3-(2-羟基苯基)丙烯腈与亚磷酸二苯酯在水中,无催化剂催化即可发生Michael加环/环化串联反应,可以高产率地生成相应的[2-氨基-3-(苯并噻唑-2-基)-4H-色烯-4-基]膦酸酯衍生物.同时,也尝试了水杨醛、2-(苯并噻唑-2-基)乙腈和亚磷酸二苯酯在Et_3N催化下的三组分一锅法反应合成相应的膦酸酯衍生物.

关键词： Michael加成环化反应膦酸酯色烯杂环化合物