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Oxidation of 3,4-dihydropyrimidin-2(1H)-ones with nitrosonium(NO^+)

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Chinese Chemical Letters 2009年第10期20卷 1183-1186页

作者： Rui Rui liang Guai li wu Wen Tao wu Long Min wu State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000 China

3,4-Dihydropyrimidin-2（1H）-ones （DHPMs） were oxidized with 1.2 equiv, of nitrosonium tetrafluoroborate （NO^＋BF4^-） to pyrimidin-2（1H）-ones in acetonitrile at room temperature in high yields.

关键词： Dihydropyrimidinone Nitrosonium Oxidation

Estimations of Three Characteristic Stress Ratios for Rockfill Material Considering Particle Breakage

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Acta Mechanica Solida Sinica 2019年第2期32卷 215-229页

作者： Wan-li Guo Zheng-Yin Cai Ying-li wu Zhi-Zhou Geng Geotechnical Engineering Department Nanjing Hydraulic Research Institute Nanjing 210024 China

The particle breakage during specimen shearing has a significant influence on the critical-state line (CSL) of the rockfill material. A series of large-scale triaxial compression tests on the rockfill material from Henan Province (HPR) were conducted in a wide range of initial void ratios and confining pressures. The influences of the particle breakage on the critical-state stress ratio Mc, the peak stress ratio Mp and dilatancy stress ratio Md were investigated. The deviatoric stress and particle breakage of the HPR at the critical state increase with the increase in confining pressure, while the influences of the initial void ratio on these behaviors are too little to be considered. The gradient of the CSL in the q-p space of the rockfilL Mc, was found to be passively correlated with the particle breakage index rather than being a constant. Additionally, the observed values of Mc at low confining pressures (low particle breakage occur) will be substantially undervalued if Mc is estimated as a constant. In the critical-state-theorybased constitutive models, Mp and Md are estimated as the combinations of Mc and state parameter 0. It is believed that the simulations of Mp and Md when Mc is correlated with Br are obviously more favorable than those when Mc is constant.

关键词： Rockfill. Particle breakage Critical-state line Stress ratio

li^(+)doping induced zero-thermal quenching in Cs_(3)Zn_(6-x-y)B_(9)O_(21):xEu^(3+),yli^(+)(0≤x≤0.10,0.06≤y≤0.16)

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Journal of Rare Earths 2023年第10期41卷 1478-1486,I0001页

作者： Yuxing Bai liwei wu Qilin Cheng li wu Yongfa Kong Yi Zhang Jingjun Xu Key Laboratory of Weak-light Nonlinear Photonics Ministry of EducationSchool of PhysicsNankai UniversityTianjin300071China College of Science Civil Aviation University of ChinaTianjin300300China Institute of Photo-electronic Thin Film Devices and Technology Nankai UniversityTianjin300071China

Thermal stability is a crucial index to assess application value of high-power LEDs,which is related to lattice ***,an effective structure-engineering strategy is proposed to achieve excellent *** the 394 nm excitation,Cs_3Zn_(5.94)B_9O_(21):0.06Eu^(3+)possesses two characteristic emissions peaked at 591 and 612 nm with limited thermal *** introducing li^(+)ions into the lattice,the sample exhibits high color purity and excellent zero-thermal quenching because the defect contents of the phosphor can be effectively modulated via charge-compensation ***,under the stimulus of high temperature,the corresponding trap levels with a suitable depth(E=1.27 eV)will release electrons to recombine with the luminescent centers,compensating for the energy *** study provides a meaningful guide for optimizing and designing novel functional photoluminescent materials.

关键词： Photoluminescence Charge compensation Lattice defects Thermal stability Rare earths

Thermal,Mechanical and Rheological Properties of Biodegradable Poly(propylene carbonate) and Poly(butylene carbonate) Blends

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Chinese Journal of Polymer Science 2015年第3期33卷 444-455页

作者： Dan-dan wu wu li Yan Zhao Yun-jiao Deng 张会良 Hui-xuan Zhang li-song Dong Changchun University of Technology Laboratory of Polymer Ecomaterials Chinese Academy of SciencesChangchun Institute of Applied Chemistry

Poly（propylene carbonate）（PPC） was melt blended in a batch mixer with poly（butylene carbonate）（PBC） in an effort to improve the toughness of the PPC without compromising its biodegradability and biocompatibility. DMA results showed that the PPC/PBC blends were an immiscible two-phase system. With the increase in PBC content, the PPC/PBC blends showed decreased tensile strength, however, the elongation at break was increased to 230% for the 50/50 PPC/PBC blend. From the tensile strength experiments, the Pukanszky model gave credit to the modest interfacial adhesion between PPC and PBC, although PPC/PBC was immscible. The impact strength increased significantly which indicated the toughening effects of the PBC on PPC. SEM examination showed that cavitation and shear yielding were the major toughening mechanisms in the blends subjected the impact tests. TGA measurements showed that the thermal stability of PPC decreased with the incorporation of PBC. Rheological investigation demonstrated that the addition of PBC reduced the value of storage modulus, loss modulus and complex viscosity of the PPC/PBC blends to some extent. Moreover, the addition of PBC was found to increase the processability of PPC in extrusion. The introduction of PBC provided an efficient and novel toughened method to extend the application area of PPC.

关键词： Biodegradable Poly(propylene carbonate) Poly(butylene carbonate) Blends,

Magnetic properties and crystallization kinetics of Zn_(0.5) Ni_(0.5) Fe_2O_4

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Rare Metals 2011年第6期30卷 621-626页

作者： wu Wenwei CAI Jinchao wu Xuehang li Yongni liAO Sen School of Chemistry and Chemical Engineering Guangxi University Nanning 530004 P.R. China

Precursor of nanocrystalline ***2O4 was obtained by grinding mixture of ZnSO4.7H2O, NiSO4.6H2O, FeSO4.7H2O, and Na2CO3.10H2O under the condition of suffactant polyethylene glycol （PEG）-400 being present at room temperature, washing the mixture with water to remove soluble inorganic salts and drying it at 373 K. The spinel Zn0.5Ni0.5Fe2O4 was obtained via calcining precursor above 773 K. The precursor and its calcined products were characterized by differential scanning calorimetry （DSC）, Fourier transform infrared （FF-IR）, X-ray diffraction （XRD）, and vibrating sample magnetometer （VSM）. The result showed that ***204 obtained at 1073 K had a saturation magnetization of 74 ***-1. Kinetics of the crystallization process of Zn0.5Ni0.5Fe2O4 was studied using DSC technique, and kinetic parameters were determined by Kissinger equation and Moynihan et al. equation. The value of the activation energy associated with the crystallization process of Zr0.5Ni0.5Fe2O4 is 220.89 kJ-mol-1. The average value of the Avrami exponent, n, is equal to 1.59±0.13, which suggests that crystallization process of Zn0.5Ni0.5Fe2O4 is the random nucleation and growth of nuclei reaction.

关键词： magnetic material Zn0.5Ni0.5Fe2O4 non-isothermal kinetics crystallization process solid-state reaction at low heat

INFLUENCE OF NOISE AND DELAY ON REACTION-DIFFUSION RECURRENT NEURAL NETWORKS

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Analysis in Theory and Applications 2006年第3期22卷 283-300页

作者： li wu Nanjing Institute of Technology China

In this paper, the influence of the noise and delay upon the stability property of reaction-diffusion recurrent neural networks （RNNs） with the time-varying delay is discussed. The new and easily verifiable conditions to guarantee the mean value exponential stability of an equilibrium solution are derived. The rate of exponential convergence can be estimated by means of a simple computation based on these criteria.

关键词： Recurrent neural networks reaction-diffusion variable delay white noise mean valueexponential stability method of variation parameter M-matrix properties stochastic analysis

Pyrrol-2-yl-methanone Modified Silica as Electron Acceptor for the Oxidation of Water Catalyzed by Cobalt（II） Complexes

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Chemical Research in Chinese Universities 2015年第5期31卷 797-800页

作者： wu Yi WANG li CHEN Qiuyun School of Chemistry and Chemical Engineering Jiangsu University Zhenjiang 212013 P. R. China

To develop a new type of non-oxidant electron acceptors for water oxidation, 3-（methyl）phenyl-（3,5- dimethyl-1H-pyrrol-2-yl）methanone modified silica（SiO2@py） was synthesized and used as host to Co4O4 cubane forming nanoparticles（SiO2@pyCo4）. In the presence of Ru（bpy）3^2＋ and under the irradiation of white LED（light emitting diode） light（10 W）, SiO2@pyCo4 can catalyze water oxidation without extra electron acceptor（e.g., Na2S2O8） Moreover, the turnover frequency（TOF） value of SiO2@pyCo4 is larger than that of Co4O4 cubane under the same conditions, and the longer lasting time of SiO2@pyCo4 indicates that SiO2@py can enhance the stability of Co4O4 in water. Our results provide an economic route to develop dioxygen evolution systems based on the assembly of organic electron acceptor modified silica with active cobalt complexes.

关键词： Silica Water oxidation Electron acceptor

Surface modification of 316L stainless steeldiamond-like carbon films

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Journal of Iron and Steel Research International 2020年第7期27卷 867-874页

作者： Rui-wu li Zheng Zhang Jian-wei li Ke-xin Ma Yuan-yuan Guo Yan-wen Zhou Fa-yu wu School of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051LiaoningChina liaoning Censcience Industrial Co. Ltd.Research and Design InstituteLiaoyang 111200LiaoningChina

The diamond-like carbon(DLC)film on 316L stainless steel substrate was preparedpulsed plasma-enhanced chemical vapor deposition,and the performance of the films was optimizedregulating the pulse *** and properties of DLC film on 316L stainless steel were characterizedatomic force microscopy,field-emission scanning electron microscopy,Raman spectra,nano-indenter and electrochemical *** results showed that DLC films with smooth and dense morphology have a low friction coefficient and high nano-indentation hardness,and the surface hardness of 316L stainless steel substrate was enhancedmore than 3 *** mechanical properties of DLC films and their bond with 316L stainless steel could be further optimizedincreasing pulse *** films on 316L stainless steel substrate increased the self-corrosion potential0.173 V and decreased self-corrosion current99%,which significantly improved the anti-corrosive properties of 316L substrate.

关键词： 316L stainless steel Diamond-like carbon film Plasma enhanced chemical vapor deposition Frictional wear Nano-indentation Corrosion resistance

Effects of argon blowing at tundish upper nozzle on multiphase flow behavior in nozzle

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Journal of Iron and Steel Research International 2022年第4期29卷 588-600页

作者： Xu-feng Qin Chang-gui Cheng Yang li Wei-li wu Yan Jin The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan 430081HubeiChina

In continuous casting,the argon blowing at the tundish upper nozzle is usually used to prevent nozzle clogging,whose effect is closely related to the migration of argon bubbles and the flow behavior of the liquid steel in the ***,to investigate the effects of argon blowing at the tundish upper nozzle on multiphase flow behavior in nozzle,a threedimensional model of the tundish–nozzle–mold was established for numerical *** results indicate that the argon bubbles injected from the inner wall of the tundish upper nozzle first move downward along the nozzle wall under the action of the liquid *** the distance from the tundish upper nozzle increases,the argon bubbles gradually diffuse to the center of the *** with no argon blowing,the liquid steel velocity increases in the center of the nozzle and decreases near the wall with argon *** increasing the argon flow rate,the concentration of bubbles in the nozzle increases,and the process of bubble group diffusion to the center region of the nozzle speeds *** in turn increases the liquid steel velocity at the center of the nozzle but reduces near the *** increasing the casting speed,the concentration of bubbles in the nozzle decreases,the length of the bubble group near the nozzle wall is extended,and the liquid steel velocity at the center region and near-wall region of the nozzle *** mechanism of argon blowing at the tundish upper nozzle to prevent nozzle clogging is mainly realized by the isolation effect of the argon bubble group on the inner wall of the nozzle.

关键词： Argon blowing Tundish upper nozzle Nozzle clogging Numerical simulation