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Visible-light-driven thio-carboxylation of alkynes with CO_(2):facile synthesis of thiochromones

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Science China Chemistry 2023年第5期66卷 1457-1466页

作者： Meng Miao lei zhu Hong Zhao lei Song Si-Shun Yan Li-Li Liao Jian-heng Ye Yu Lan da-Gang Yu Key Laboratory of Green Chemistry&Technology of Ministry of Education College of ChemistrySichuan UniversityChengdu 610064China College of Pharmacy Third Military Medical UniversityChongqing 400038China School of Chemistry and Chemical Engineering Chongqing Key Laboratory of Theoretical and Computational ChemistryChongqing UniversityChongqing 400030China College of Chemistry and Institute of Green Catalysis Zhengzhou UniversityZhengzhou 450001China

Difunctionalizing carboxylation of alkynes with CO_(2)is a sustainable and important strategy to generate valuable acrylate derivatives from both readily available starting *** protocols,however,always suffer from the use of excess metallic reagents and transition metal ***,we report the first thio-carboxylation of alkynes with thiophenols and CO_(2),which is a visible-light-driven and transition metal-free *** contrast to previous carboxylations of alkynes via two-electron activation of CO_(2),mechanistic and computational investigations suggest that the single-electron activation of CO_(2)is involved in the thio-carboxylation,rendering uniqueβ-*** following cyclizing acylation affords important thiochromones ***,the one-pot method features mild reaction conditions(room temperature,1 atmosphere of CO_(2)),high chemo-and regio-selectivity,easy scalability and facile derivatization of products to bioactive compounds.

关键词： carbon dioxide visible light carboxylation thiochromones

Dual-Mode Resonant Sectorial Monopole Antenna with Stable Backfire Gain

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Chinese Journal of Electronics 2024年第6期33卷 1478-1486页

作者： Feiyan JI heng ZHANG Xiuqiong XING Wenjun LU lei zhu Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and Telecommunications Key Laboratory of Wireless Sensor Network & Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Department of Electrical and Computer Engineering Faculty of Science and Technology University of Macau

A novel design approach to wideband, dual-mode resonant monopole antenna with stable, enhanced backfire gain is advanced. The sectorial monopole evolves from a linear, 0.75-wavelength electric prototype monopole under wideband dual-mode resonant operation. As theoretically predicted by the two resonant modes TE3/5,1and TE9/5,1within a 150° radiator, the operation principle is revealed at first. As have been numerically demonstrated and experimentally validated at 2.4-GHz band, the designed antenna exhibits a wide impedance bandwidth over 90.1%（i.e., 2.06–5.44 GHz）, in which the stable gain bandwidth in the backfire,-x-direction（θ = 90°, φ = 180°） with peak value of 3.2 dBi and fluctuation less than 3 dB is up to 45.3%（i.e., 3.74–5.44 GHz）. It is concluded that the stable wideband backfire gain frequency response should be owing to the high-order resonant mode in the unique sectorial monopole antennas.

关键词： Fluctuations Azimuth Prototypes Metals Resonance Frequency measurement Broadband antennas Impedance Gain Wideband

Accurate Analytic Potential Energy Function and Spectroscopic Study for G^1Ⅱg State of Dimer ^7Li2

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Communications in Theoretical Physics 2007年第6期47卷 1114-1120页

作者： SHI De-heng ma heng SUN Jin-Feng zhu Zun-Lue College of Physics ＆ Electronic Engineering Xinyang Normal University Xinyang 464000 China College of Physics ＆ Information Engineering Henan Normal University Xinxiang 453007 China

The reasonable dissociation limit for the G^1Ⅱg, state of dimer ^7Li2 is determined. The equilibrium internuclear distance, dissociation energy, harmonic frequency, vibrational zero energy, and adiabatic excitation energy are calculated using a symmetry-adapted-cluster configuration-interactlon method in complete active space in Gaussian03 program package at such numerous basis sets as 6-311 ＋＋G, 6-311 ＋＋G（2df,2pd）, 6-311 ＋＋G（2df, p）, cc-PVTZ, 6- 311＋＋G（3df,3pd）, CEP-121G, 6-311＋＋G（2df, pd）, 6-311＋＋G（d,p）,6-311G（3df,3pd）, D95（3df,3pd）, 6-311＋＋G（3df,2p）, 6-311＋＋G（2df）, 6-311＋＋G（df, pd） D95V＋＋, and DGDZVP. The complete potential energy curves are obtained at these sets over a wide internuclear distance range and have least squares fitted to Murrell-Sorbie function. The conclnsion shows that the basis set 6-311＋＋G（2df, p） is a most suitable one for the G^1Ⅱg state. At this basis set, the calculated spectroscopic constants Te, De, Eo, Re, ωe, ωeXe, ae, and Be are of 3.9523 eV, 0.813 06 eV, 113.56 cm^-1, 0.320 15 nm, 227.96 cm^-1, 1.6928 cm^-1, 0.004 436 cm^-1, and 0.4689 cm^-1, respectively, which are in good agreement with measurements whenever available. The total 50 vibrational levels and corresponding inertial rotation constants are for the first time calculated and compared with available RKR data. And good agreement with measurements is obtained.

关键词： vibrational frequency dissociation energy Li2 ab initio calculations

Hydrothermal synthesis of pure-phase hierarchical porous hexagonal WO3microspheres as highly efficient support for Pd catalyst for hydrogenation

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Particuology 2018年第6期16卷 126-132页

作者： heng Zhang Jiajia Wang Xu Liu Xinxin ma Wancheng zhu School of Chemistry and Chemical Engineering Qufu Normal UniversityShandong 273165China

Hexagonal tungsten trioxide (h-WO3)microspheres were synthesized by a hydrothermal method,with ammonium paratungstate and hydrochloric acid as the raw *** effects of the process parameters on the phase compositions and morphologies of the products were *** results showed that the hydrothermal temperature and molar ratio of the raw materials were important for avoiding the formation of impurity phases,namely WO3.0.33H2Oand *** pure-phase h-WO3microspheres had a specific surface area of 40.0m^2/g,and were assembled from *** microspheres were used to support Pd,and the obtained Pd/h-WO3catalyst showed excellent catalytic activity in the hydrogenation of styrene under mild conditions,with a turnover frequency 0f 3050h^-*** catalyst was recycled five times without loss of activity,i.e.,the supported catalyst had good recyclability.

关键词： Tungsten trioxide Hydrothermal synthesis Supported catalyst Hydrogenation

A Survey of Newtonian Core-Shell Systems with Pseudo High Order Symplectic Integrator and Fast Lyapunov Indicator

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Chinese Journal of Astronomy and Astrophysics 2007年第4期7卷 601-610页

作者： Jun-Fang zhu Xin Wu da-zhu ma Department of Physics Nanchang University Nanchang 330031

Newtonian core-shell systems, as limiting cases of relativistic core-shell models under the two conditions of weak field and slow motion, could account for massive circumstellar dust shells and rings around certain types of star remnants. Because this kind of systems have Hamiltonians that can be split into a main part and a small perturbing part, a good choice of the numerical tool is the pseudo 8th order symplectic integrator of Laskar ＆ Robutel, and, to match the symplectic calculations, a good choice of chaos indicator is the fast Lyapunov indicator （FLI） with two nearby trajectories proposed by Wu, Huang ＆ Zhang. Numerical results show that the FLI is very powerful when describing not only the transition from regular motion to chaos but also the global structure of the phase space of the system.

关键词： celestial mechanics - chaos - methods: numerical

A new correction method for quasi-Keplerian orbits

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Research in Astronomy and Astrophysics 2020年第11期20卷 191-204页

作者： Yue Chen da-zhu ma Fang Xia Purple Mountain Observatory Chinese Academy of SciencesNanjing 210033China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China School of Information and Engineering Hubei Minzu UniversityEnshi 445000China

A pure two-body problem has seven integrals including the Kepler energy,the Laplace vector and the angular momentum ***,only five of them are *** the five independent integrals are preserved,the two other dependent integrals are naturally preserved from a theoretical viewpoint;but they may not necessarily be from a numerical computational *** of this,we use seven scale factors to adjust the integrated positions and velocities so that the adjusted solutions strictly satisfy the seven *** the existence of the two dependent integrals,we adopt the Newton iterative method combined with singular value decomposition to calculate these *** correction scheme can be applied to perturbed two-body and N-body problems in the solar *** this case,the seven quantities associated with each planet slowly vary with *** accurate values can be given to the seven slowly-varying quantities by integrating the integral invariant relations of these quantities and the equations of *** should be satisfied with the adjusted *** tests show that the new method can significantly reduce the rapid growth of numerical errors for all orbital elements.

关键词： Computational methods Computational astronomy planets and satellites dynamical

Porous hybrid scaffold strategy for the realization of lightweight,highly efficient microwave absorbing materials

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Journal of materials Science & Technology 2022年第34期129卷 215-222页

作者： Meng zhu Yuting lei heng Wu Luo Kong Hailong Xu Xuanxuan Yan Yongjian Xu lei dai Shaanxi Provincial Key Laboratory of Papermaking Technology and Specialty Paper Development Key Laboratory of Paper Based Functional MaterialsChina National Light IndustryNational Demonstration Center for Experimental Light Chemistry Engineering EducationShaanxi University of Science and TechnologyXi’an 710021China School of Engineering Computer and Mathematics SciencesAuckland University of Technology55 Wellesley Street EastAucklandNew Zealand School of materials Science and Engineering Shaanxi University of Science and TechnologyXi’an 710021China Laboratory for Advanced Interfacial materials and Devices Research Center for Smart Wearable TechnologyInstitute of Textiles and Clothingthe Hong Kong Polytechnic UniversityHong Kong SAR 999077China

Exploring an advanced and efficient electromagnetic(EM) wave absorbing material by improving dielectric loss capacity and adjusting impendence matching is crucial yet challenging. Herein, the bacterial cellulose(BC) derived carbon aerogel(CA) with a robust nanofibrous network was used as a conductive loss scaffold to dissipate EM waves effectively, and the Zn O microparticles with excellent dielectric properties and low electrical conductivity were decorated on the scaffold to adjust dielectric parameters and impedance matching adequately. By using different zinc precursors, the tunable size and morphologies of Zn O crystals were obtained due to the growth rate of different crystallographic, including flowerlike, nanorod like, and cauliflower-like morphologies, which is beneficial to strong multiple reflections,intensive interfacial polarization, better impendence matching, as well as excellent maintenance of the hierarchical structure. Owing to the appropriate impendence matching and the considerable EM wave dissipation, the CA@ZnO composites achieve a superior EM absorbing performance with a broad effective absorbing bandwidth(whole X band) and a minimum reflection coefficient(-53.3 d B). This work paves a new way for developing lightweight and highly efficient EM absorbing materials comprising the carbon scaffold and semiconductor microparticles.

关键词： Carbon scaffold ZnO microparticles Morphologies Impedance matching Microwave absorption

Ground fissure development regularity and formation mechanism of shallow buried coal seam mining with Karst landform in Jiaozi coal mine: a case study

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Journal of Mountain Science 2023年第10期20卷 3101-3120页

作者： zhu heng-zhong School of Energy and Mining Engineering Shandong University of Science and TechnologyQingdao 26659oChina State Key Laboratory of Strata Intelligent Control and Green Mining Co-Founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and TechnologyQingdao 266590China State Key Laboratory of Water Resource Protection and Utilization in Coal Mining Beijing 102209China

A comprehensive study was undertaken at Jiaozi coal mine to investigate the development regularity of ground fissures in shallow buried coal seam mining with Karst landform,shedding light on the development type,geographical distribution,dynamic development process,and failure mechanism of these ground fissures by employing field monitoring,numerical simulation,and theoretical *** findings demonstrate that ground fissure development has an obvious feature of subregion,and its geographical distribution is significantly affected by *** type,open type,and stepped type are three different categories of ground *** fissures emerge dynamically as the panel advances,and they typically develop with a distance of less than periodic weighting step distance in advance of panel advancing *** fissures present the dynamic development feature,temporary fissure has the ability of *** dynamic development process of ground fissure with closed-distance coal seam repeated mining is expounded,and the development scale is a dynamic development stage of“closure→expansion→stabilized”on the basis of the original development *** the perspective of topsoil deformation,the computation model considering two points movement vectors towards two directions of the gob and the ground surface is established,the development criterion considering the critical deformation value of topsoil is *** mechanical model of hinged structure of inclined body is proposed to clarify the ground fissure development,and the interaction between slope activity and ground fissure development is *** research results fulfill the gap of ground fissures about development regularity and formation mechanism,and can contribute to ground fissure prevention and treatment with Karst landform.

关键词： Karst landform Shallow buried coal seam Development regularity Formation mechanism Ground fissure Repeated mining

A numerical study of hydrodynamic characteristics and hydrological processes in the coastal wetlands during extreme events

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Journal of Hydrodynamics 2023年第5期35卷 963-979页

作者： Ming-liang Zhang Xiao-sen zhu Yu-jia Wang heng-zhi Jiang lei Cui College of Ocean Science and Environment Dalian Ocean UniversityDalian116023China Technology Innovation Center for Coastal Ecological Environment and Disaster Protection Liaoning ProvinceDalian116023China National marine Environmental Monitoring Center Dalian116023China

Providing accurate predictions of extreme water levels through numerical simulation has become essential for disaster prevention and damage mitigation in coastal wetland *** study applies the FVCOM model to simulate storm surges caused by several typhoons in the Bohai Sea and the North Huanghai *** vegetation drag force caused by salt marsh plants is inserted into the FVCOM model for model improvement with vegetation effect by integrating RS and GIS technologies.A parametric typhoon model is coupled with background wind fields derived to acquire the spatio-temporal variations of wind and pressure fields in the computational *** simulation results reproduce the extreme storm surges induced by typhoon events very *** modeling results are compared by validating with literature results to examine the effect of vegetation on tidal waves in tidal mud ***,the coupled model is also applied to explore storm surge attenuation and land intrusion during Typhoon Winnie in the wetlands of the Liao River *** simulation results indicate that salt marsh plants can reduce the flow current with little impact on tide flooding/ebbing in vegetated ***,the results show that typhoon presence increases the inundation depth and extendes the flood time in the tidal wetlands of the study *** FVCOM model incorporating the method with vegetation drag force can provide new insights to understand the comprehensive impact of tidal wetland plants on hydrodynamic characteristics in the Bohai Sea and other waters,hence presents a more accurate quantification of the hydrological process of storm surge in the tidal wetlands.

关键词： FVCOM circulation model Parametric typhoon model coastal wetlands storm surge hydrological process