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Chinese Chemical Letters 2015年第5期26卷 539-542页

作者： Xue-Dong Li Ran ma Liang-Nian he State Key Laboratory of Elemento-Organic Chemistry Collaborative Innovation Center of Chemical Science and Engineering(Tianjin)Nankai University

Selective oxidation of sulfides to sulfoxides was successfully performed by employing readily available Fe（NO3）3-9h2O as the active catalyst with oxygen as the oxidant in 2,2,2-trifluoroethanol （TFE） without the formation of sulfones. Nitrate anion could play a crucial role in promoting the reaction due to the oxidation capacity under acidic media. high yields of sulfoxides were exclusively obtained from the corresponding sulfides. Furthermore, both.aromatic and aliphatic sulfides gave moderate to high yields of sulfoxides with this protocol.

关键词： FeiNO3)3.9h2O TFE Oxidation Sulfox[des

hⅠVertical Structure of Nearby Edge-on Galaxies from ChANG-ES

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Research in Astronomy and Astrophysics 2022年第8期22卷 49-62页

作者： Yun Zheng Jing Wang Judith Irwin QDaniel Wang Jiangtao Li Jayanne English Qingch.an ma Ran Wang Ke Wang marita Krause Toky h.Randriamampandry Rainer Beck Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Department of Physics Engineering Physics&AstronomyQueen’s UniversityKingstonONK7L 3N6Canada Astronomy Department University of MassachusettsAmherstMA 01003USA Department of Astronomy University of MichiganAnn ArborMI48109-1107USA Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China Department of Physics and Astronomy University of ManitobaWinnipegManitobaR3T 2N2Canada max-Planck-Institut für Radioastronomie Auf dem Hügel D-6953121 BonnGermany

We study the vertical distribution of the highly inclined galaxies from the Continuum halos in Nearby Galaxies—an EVLA Survey(ChANG-ES).We explore the feasibility of photometrically deriving the hⅠdisk scale heights from the moment-0 images of the relatively edge-on galaxies with inclination>80°,by quantifying the systematic broadening effects and thus deriving correction equations for direct *** corrected hⅠdisk scale heights of the relatively edge-on galaxies from the ChANG-ES sample show trends consistent with the quasiequilibrium model of the vertical structure of gas *** procedure provides a convenient way to derive the scale heights and can easily be applied to statistical samples in the future.

关键词： galaxies:ISM galaxies:spiral galaxies:structure

Photoluminescence and ratiometric thermo-response of Eu^(2+)and Eu^(3+)in BaAl_(2)B_(2)O_(7):Eu^(2+),Eu^(3+)phosphor materials

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Journal of Rare Earths 2024年第7期42卷 1240-1249,I0002页

作者： Ziyao Wang haitao Fu Xiufeng Zhan Bo Tong Guofeng ma h.T.(Bert)hintzen Institute of Innovative Science and Technology Shenyang UniversityShenyang110044China College of Mechanical Engineering Shenyang UniversityShenyang110044China Faculty of Applied Sciences Delft University of Technology2629 JBDelftthe Netherlands

A novel Eu^(2+)-Eu^(3+)co-activated ratiometric thermo-sensitive phosphor was developed and synthesized by solid-state *** valence state of Eu,photoluminescence and thermo-sensitive performance of the phosphor prepared either in ambient air or carbothermally were investigated and *** phosphor shows high sensitivity(Sa=0.0173 K^(-1),S_(r)=0.461%/K)and superior signal discriminability(Δν∼10380 cm^(−1)).The thermo-sensitive performance is subject to the dual effects of different thermo-responses by Eu^(2+)versus Eu^(3+)combined with energy transfer from Eu^(2+)to Eu^(3+),so that the sensitivity of the phosphor in the temperature range presents a non-monotonic *** development of the BaAl_(2)B_(2)O_(7):Eu^(2+),Eu^(3+)phosphor is not only expected to be relevant for application in the field of temperature sensing,but also of reference significance for improving the sensitivity by means of energy transfer between co-activator ions over a wider temperature range of Eu^(2+)-Eu^(3+)co-activated ratiometric thermo-sensitive phosphors.

关键词： Photoluminescence Ratiometric thermo-response Phosphor Eu^(2+)/Eu^(3+) Rare earths

A Study of the Influence of Solid Particles on Boiling hysteresis

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Journal of Thermal Science 1992年第1期1卷 41-45页

作者： M.h.Shi J.ma South.ast University Nanjing 210018China

Experiments have been performed to determine the effects on boiling hysteresis of locally fluidized particles contained in a liquid that serves as coolant for electronic *** results show that locally fluidized particl... 详细信息

关键词： boiling hysteresis effects of locally fluidized particles.

Design and testing of a global climate prediction system based on a coupled climate model

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Science China Earth Sciences 2014年第8期57卷 2417-2427页

作者： ma Jieh.a WANG huiJun Climate Change Research Center Chinese Academy of Sciences Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences

A global climate prediction system （PCCSM4） was developed based on the Community Climate System Model, version 4.0, developed by the National Center for Atmospheric Research （NCAR）, and an initialization scheme was designed by our group. Thirty-year （1981-2010） one-month-lead retrospective summer climate ensemble predictions were carded out and analyzed. The results showed that PCCSM4 can efficiently capture the main characteristics of JJA mean sea surface temperature （SST）, sea level pressure （SLP）, and precipitation. The prediction skill for SST is high, especially over the central and eastern Pacific where the influence of E1 Nino-Southem Oscillation （ENSO） is dominant. Temporal correlation coefficients between the pre- dicted Nino3.4 index and observed Nino3.4 index over the 30 years reach 0.7, exceeding the 99% statistical significance level. The prediction of 500-h.a geopotential height, 850-h.a zonal wind and SLP shows greater skill than for precipitation. Overall, the predictability in PCCSM4 is much higher in the tropics than in global terms, or over East Asia. Furthermore, PCCSM4 can simulate the summer climate in typical ENSO years and the interannual variability of the Asian summer monsoon well. These preliminary results suggest that PCCSM4 can be applied to real-time prediction after further testing and improvement.

关键词： climate model climate prediction ENSO monsoon

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Design, Synthesis and Biological Activities of Novel N-Aryl-1h-pyrazole-5-carboxylate Derivatives

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Chemical Research in Chinese Universities 2020年第5期36卷 853-858页

作者： ZhANG Xiulan ZhANG h.an ma Jinlong YU Shujing LI Zhcngming College of Science Tianjin University of Science&TechnologyTianjin 300457P.R.China State Key Laboratory of Elemento-Organic Chemistry Institute of Elemento-Organic ChemistryNankai UniversityTianjin 300071P.R.China

In an attempt to search for potent fungicide,a series of novel N-ary 1-1h-pyrazole-5-carboxylate derivatives was designed and *** chemical structures were characterized by 1h NMR spectra and high reso・lution mass spectrometry(hRMS).The preliminary bioassay results indicated that some target compounds displayed better fungicidal activities against certain fungi at 50μg/mL or favorable antitumor activities at 5 μg/mL compared with chlorothalonil and 5-fluorouracil,*** structure-activity relationship demonstrated that the introduction of ester group and amide bond was favorable to the improvement of activities against Physalospora pin cola and Phytophthora capsici.

关键词： N-Aryl-1h-pyTazole-5-carboxylate Fungicidal activity Antitumor activity

Transition-metal-catalyzed remote meta-C-h.alkylation and alkynylation of aryl sulfonic acids enabled by an indolyl template

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Chinese Chemical Letters 2024年第8期35卷 254-259页

作者： Pengfei Zhang Qingxue ma Zhiwei Jiang Xiaoh.a Xu Zhong Jin College of Chemistry State Key Laboratory of Elemento-organic ChemistryNankai UniversityTianjin 300071China Key Laboratory of Xinjiang Native Medicinal and Edible Plant Resource Chemistry College of Chemistry and Environmental SciencesKashi UniversityKashgar 844007China

Transition-metal-catalyzed remote sp^(2)C-h functionalization of aryl sulfonic acids was hardly ever real-ized owing to competitive ortho-C-h functionalization of aryl sulfonates and electron-deficient nature of phenyl ***,with the assistance of a practical biaryl indolyl directing template,palladium-catalyzed remote sp^(2)C-h.alkylation of aryl sulfonic acids have been achieved in moderate to good yields with exclusive meta ***,remote meta-selective C-h.alkynylation of aryl sulfonic acids was also accomplished with.a rhodium *** meta-C-h functionalized products proved to be the superior synthetic precursors,which.are difficult to access using the conventional strategy.

关键词： C-h functionalization Aryl sulfonic acid Site-selectivity Transition-metal catalysis Alkylation Alkynylation

Importance of metal location in M-h zeolite for synergistically catalyzing dimethyl ether carbonylation

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Chinese Journal of Chemical Engineering 2022年第1期35卷 350-357页

作者： Shiyue Li Shouying h.ang Kai Cai Ying Li Jing Lv Xinbin ma Key Laboratory for Green Chemical Technology of Ministry of Education Collaborative Innovation Center of Chemical Science and EngineeringSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China

Mordenite(MOR)has shown great potential to catalyze dimethyl ether(DME)carbonylation to methyl acetate(ma)in *** synergy between metal species and Brønsted acid sites accelerates DME *** we designed and prepared two catalysts with different Ag locations by seed-directed growth method and two-step impregnation method(named as Ag@hMOR and Ag/hMOR-out,respectively),to explain the effect of Ag location on catalytic *** results of TEM,XPS,CO-IR and UV–Vis showed that Ag species mainly presented as Ag^(0) species over both.ag@hMOR and Ag/***,Ag^(0) species mainly located in the micropores of Ag@hMOR,while as for Ag/hMOR-out,Ag^(0) mainly existed on external *** comparing the performance of the catalysts with different Ag positions,we confirmed that the Ag^(0) species encapsulated in the channels of hMOR promoted the DME carbonylation,which revealed the importance of spatial adjacency on the acid-metal catalysts.

关键词： Dimethyl ether Carbonylation Silver modification Metal location

Gain-scheduled h_(2)/h_(∞)filtering for linear discrete-time systems with polytopic uncertainties

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Frontiers of Electrical and Electronic Engineering in China 2008年第2期3卷 208-213页

作者： Qingliang ma Changh.a hU Department of Automation Xi’an Research Institute of High-TechXi’an 710025China

The design of the gain-scheduled h_(2)/h_(∞)filter for polytopic discrete-time systems is *** introducing additional slack variables,a new mixed h_(2)/h_(∞)performance criterion is proposed,which provides a decoupling between the Lyapunov matrix and system *** on the new performance criterion,a sufficient condition for the existence of the gain-scheduled h_(2)/h_(∞)filter is ***,the filter design problem is converted into a convex optimization problem with linear matrix inequality(LMI)*** results show the effectiveness of the proposed approach.

关键词： mixed h_(2)/h_(∞)filtering gain-scheduled filtering convex optimization linear matrix inequality(LMI)

Identifying the active photocatalytic h2-production sites on TiO2-supported Pt nanoparticles by the in-situ infrared spectrum of CO

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Science China Chemistry 2020年第3期63卷 354-360页

作者： Peng Zhou hongna Zhang hongwei Ji Wanhong ma Chuncheng Chen Jincai Zhao Key Laboratory of Photochemistry Beijing National Laboratory for Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Identifying the active catalytic centers on catalyst surface is significant for exploring the catalytic reaction mechanism and further guiding the synthesis of high-performance ***,it remains a challange in developing the site-specific technology for the identification of the active catalytic ***,in-situ infrared spectroscopy of adsorbed CO,photocatalytic hydrogen evolution reaction(hER)test and theoretical simulation were used to distinguish.and quantify the different surface sites and their h2-production catalytic activity on TiO2-supported Pt nanoparticles(Pt NPs).Two different types of surface Pt sites,tip Pt(Pttip)and edge/terrace Ptedge/terrace,on TiO2-supported Pt nanoparticles(Pt NPs)were *** photocatalytic h2-production activity of TiO2-supported Pt NPs shows a linear functional relationship with the number of Pttip ***,the number of Ptedge/terracesites produced little effect on the activity of TiO2-supported Pt ***-principle simulations confirmed that h2-evolution at the Pttipsites owns a lower energy barrier than that at Ptedge/*** findings would be helpful for the fabrication of high-performance Pt catalysts.

关键词： Pt nanocatalyst h2 production photocatalyst active site in-situ IR