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Chemical Research in Chinese Universities 2000年第2期16卷 131-135页

作者： wang yulan WU Yangjie Chinese Acad Sci Inst Chem Met Natl Key Lab Biochem Engn Beijing 100080 Peoples R China Zhengzhou Univ Dept Chem Zhengzhou 450052 Peoples R China

A series of symmetrical biaryls was synthesized from arylmercuric chlorides and biarylmercurials in the presence of [ClRh(CO) 2] 2 in hexamethylphosphoramide(HMPA). The mechanism of the [ClRh(CO) 2] 2 catalyzed d... 详细信息

关键词： Symmetrical biaryls Synthesis Arylmercurials Intermolecular reaction

Immediate regularization of measure-type population densities in a two-dimensional chemotaxis systemwith signal consumption

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Science China Mathematics 2021年第4期64卷 725-746页

作者： yulan wang Michael Winkler Zhaoyin Xiang School of Science Xihua UniversityChengdu 610039China Institut für Mathematik Universität PaderbornPaderbom 33098Germany School of Mathematical Sciences University of Electronic Science and Technology of ChinaChengdu 611731China

This paper deals with the Neumann initial-boundary value problem for a classical chemotaxis system with signal consumption in a *** contrast to previous studies which have established a comprehensive theory of global classical solutions for suitably regular nonnegative initial data,the focus in the present work is on the question to which extent initially prescribed singularities can be regularized despite the presence of the nonlinear cross-diffusive *** main result in this paper asserts that at least in the framework of radial solutions immediate regularization occurs under an essentially optimal condition on the initial distribution of the population *** precisely,it will turn out that for any radially symmetric initial data belonging to the space of regular signed Borel measures for the population density and to L^(2) for the signal density,there exists a classical solution to the Neumann initial-boundary value problem,which is smooth and approaches the given initial data in an appropriate trace sense.

关键词： chemotaxis measure valued initial data instantaneous smoothing global existence

Challenges in Analysis of Hydrophilic Metabolites Using Chromatography Coupled with Mass Spectrometry

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Journal of Analysis and Testing 2020年第3期4卷 140-162页

作者： Qingyu Hu Huiru Tang yulan wang CAS Key Laboratory of Magnetic Resonance in Biological Systems State Key Laboratory of Magnetic Resonance and Atomic and Molecular PhysicsNational Centre for Magnetic Resonance in WuhanWuhan Institute of Physics and MathematicsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of Sciences(CAS)Wuhan 430071People’s Republic of China University of Chinese Academy of Sciences Beijing 10049People’s Republic of China State Key Laboratory of Genetic Engineering Zhongshan Hospital and School of Life SciencesLaboratory of Metabonomics and Systems BiologyHuman Phenome InstituteFudan UniversityShanghai 200433People’s Republic of China Singapore Phenome Center Lee Kong Chian School of MedicineNanyang Technological UniversitySingapore 639798Singapore

Hydrophilic metabolites play important roles in cellular energy metabolism,signal transduction,***,there are challenges in both identification and quantification of the hydrophilic metabolites due to their weak interactions with C18-reversed-phase liquid chromatography(RPLC),leading to poor retention of hydrophilic metabolites on the *** strategies have been put forward to increase the retention behavior of hydrophilic metabolites in the RPLC ***-derivatization methods are mainly focused on the development of new chromatographic techniques with different separation mechanisms,such as capillary electrophoresis,ion-pairing RPLC *** methods improve the hydrophobicity of metabolites and can enhance the MS *** review mainly focused on the illustration of challenges of LCMS in the analysis of hydrophilic metabolomics field,and summarized the non-derivatization and derivatization strategies,with the intention of providing multiple choices for analysis of hydrophilic metabolites.

关键词： Hydrophilic metabolites Hydrophilic interaction chromatography Ion-pairing reversed-phase liquid chromatography Ion chromatography Capillary electrophoresis Derivatization

Premixed Gas Mixing Performance of Lobe-Forced Mixer at Different Configurations

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Journal of Thermal Science 2022年第3期31卷 895-906页

作者： wang yulan MU Yong LU Haitao FAN Xiongjie XU Gang Key Laboratory of Light-Duty Gas-Turbine Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China

The mixing process of pre-evaporated afterburner fuel at different positions upstream of the mixers and airflow was numerically simulated in a straight channel,with semicircular mixer,rectangular mixer,triangular mixer and chevron mixer *** effects of vortices generated by mixers on fuel distribution and mixing characteristics were *** results show that:(1)The scale,strength and breaking speed of the streamwise vortex and the development speed of normal vortex are different downstream of the four mixers,which accelerate the mixing process of fuel and airflow.(2)The fuel distribution at the outlet of mixers,downstream of straight section and downstream of the crest and trough is mainly affected by secondary flow,the streamwise vortex and the normal vortex respectively.(3)The fuel mixing uniformity downstream of the four mixers is increased by about 80%compared with no *** the limited distance,the mixing performance of chevron mixer is the best,while the triangular mixer is the worst Rectangular mixer has the fastest mixing speed and superior comprehensive *** addition,the effect of the channel wall on the mixing process downstream of mixers cannot be ignored.

关键词： afterburner mixing performance lobe-forced mixer fuel vortex

On the Application of a Mobile Grid Technology to Computational Fluid Dynamics

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Fluid Dynamics & Materials Processing 2019年第4期15卷 357-366页

作者： Zhiyuan Cheng yulan wang Yingang wang Qiong Nie School of Architecture and Materials Engineering Hubei University of EducationWuhan430205China BIM Technology Application Engineering Center Hubei University of EducationWuhan430205China

On the basis of harmonic mapping theory,a mobile grid technology is applied to computational fluid dynamics(CFD).Starting from the observation that standard fixed-grid techniques often fail in addressing problems with large deformations,we elaborate a new algorithm relying on the software COMSOL Multiphysics 5.3a to solve the coupling of the mobile grid equation and the governing differential equations for fluid *** motion of water in a water tank when the tank waggles is *** demonstrate that this technology can be implemented without a significant increase in the computational cost with respect to standard numerical methods.

关键词： Harmonic mapping mobile grid computational fluid dynamics large deformation

Development and validation of an improved probabilistic quotient normalization method for LC/MS-and NMR-based metabonomic analysis

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Chinese Chemical Letters 2020年第7期31卷 1827-1830页

作者： Yanpeng An Si Liu Fuhua Hao yulan wang Huiru Tang State Key Laboratory of Genetic Engineering Zhongshan Hospital and School of Life SciencesHuman Phenome InstituteMetabonomics and Systems Biology Laboratory at Shanghai International Centre for Molecular PhenomicsFudan UniversityShanghai 200438China C4S Key Laboratory of Magnetic Resonance in Biological Systems Stare Key Laboratory of Magnetic Resonance and Atomic and Molecular PhysicsWuhan Institute of Physics and MathematicsUniversity of Chinese Academy of SciencesWuhan 430071China Singapore Phenome Center Lee Kong Chian School of MedicineSchool of Biological SciencesNanyang Technological UniversitySingapore 636921Singapore

Robust normalization is a prerequisite for reliable metabonomic analysis especially when intervention treatments cause drastic metabolomic changes or when spot urinary samples are employed without knowing the drinking water *** the simulated and real datasets,here,we report a probabilistic quotient normalization method based on the mode-of-quotients(mPQN)which is suitable for metabonomic analysis of both NMR and LC-MS data with little and/or drastic metabolite *** applied to metabonomic analysis of both animal plasma samples and human urinary samples,this newly proposed method has clearly shown better robustness than all classical normalization methods especially when drastic changes of some metabolites occur.

关键词： Metabonomics Normalization Probabilistic quotient normalization NMR LC-MS

The Effect of Different Reaction Mechanisms on Combustion Simulation of a Reverse-Flow Combustor

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Journal of Thermal Science 2020年第3期29卷 793-812页

作者： LU Haitao LIU Fuqiang wang yulan FAN Xiongjie LIU Cunxi XU Gang Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Three different reaction mechanisms of kerosene and flamelet models were used to simulate combustion in a reverse-flow *** comparing the effects of different mechanisms on the flow field characteristics,components and temperature distribution of the combustion chamber,the results showed that:Under different reaction mechanisms,there was a strong similarity between flow filed and temperature field,but the penetration depth and temperature distribution of local jets were affected by the *** to the different reaction paths and reaction rates,the distribution of major components had a great degree of similarity,but the concentration of intermediate components varied *** analysis,the 16 species and 17 species reaction mechanisms can simulate the flow field and outlet temperature distribution of the combustor well.

关键词： reaction mechanisms reverse-flow combustor flamelet models combustion simulation

Production of Bio-hydrogen Using Bio-oil as a Potential Biomass-derived Renewable Feedstock

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Chemical Research in Chinese Universities 2019年第2期35卷 285-291页

作者： LIU Junxu ZHU Lijuan wang Shengfei wang yulan HE Yuting LI Quanxin Key Laboratory of Urban Pollutant Conversion of Chinese Academy of Sciences Anhui Key Laboratory of Biomass Clean EnergyDepartment of Chemical PhysicsUniversity of Science & Technology of ChinaHefei 230026P.R.China

The bio-oil derived from pyrolysis of straw can be selectively converted into high-purity hydrogen by coupling three steps:(i)steam refonning(SR)of di tierent bio-oils,(ii)water-gas shift(WGS),and(iii)the removal of *** catalytic SR reaction over the NiLaTiAl catalyst,coupled with a low-temperature WGS reaction with the CuZnAl catalyst,promoted the conversion of various oxygen-contaming organic compounds in the bio-oil into hydrogen and carbon *** the optimized condition,light bio-oil achieved the highest conversion(99.8%,molar fraction),with a high hydrogen yield of 16.4%(mass traction)and a H2 purity of 99.94%(volume fraction).The carbon deposition on the NiLaTiAl catalyst was the main factor caused catalyst *** of hydrogen from different bio-oil model compounds was also investigated in detail.

关键词： Bio-oil Higli-purity hydrogen Integrated catalytic process Oxygenated organic compound

Enhancement of Bio-based para-Xylene Selectivity in Catalytic Fast Pyrolysis of Cellulose Using a Surface-modified Mg/P/HZSM-5 Catalyst

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Chemical Research in Chinese Universities 2019年第3期35卷 449-456页

作者： wang yulan FAN Minghui ZHU Lijuan wang Shengfei HE Yuting LI Quanxin Department of Chemical Physics CAS Key Laboratory of Urban Pollutant ConversionChinese Academy of SciencesAnhui Key Laboratory of Biomass Clean EnergyUniversity of Science & Technology of ChinaHefei 230026P.R.China

With the growing consumption of oil, the production of /?-xylene(PX) from renewable biomass has gained significant attention recently. This work demonstrated that cellulose, a main component in lignocellulosic biomass, was directly converted into PX over the Mg/P surface-modified zeolites. The catalysts modified by the incorporation of P2O5 and MgO into HZSM-5(HZ) promoted the isomerization of zw-/o-xylenes to p-xylene. The PX selectivity was greatly enhanced using the modified zeolites due to the deactivation of external surface and the adjustment of pore entrance. In addition, the addition of methanol to cellulose was beneficial to increase the selectivity of xylenes due to the alkylation reactions and the Diels-Alder reactions between cellulose-derived furans and methanol-derived olefins. The highest PX yield of 10.7%(molar fraction) with a high PX selectivity in xylenes(97.1%) was obtained over the 10%Mg/5%P/HZ catalyst. The reaction pathway for the formation ofp-xylene was addressed according to the study of the key reactions and the characterization of catalysts.

关键词： Cellulose p-Xylene Diels-Alder reaction Isomerization Alkylation

Numerical Simulation of the Fractional-Order Lorenz Chaotic Systems with Caputo Fractional Derivative

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Computer Modeling in Engineering & Sciences 2023年第5期135卷 1371-1392页

作者： Dandan Dai Xiaoyu Li Zhiyuan Li Wei Zhang yulan wang School of Physics and Electronic Information Engineering Jining Normal UniversityJining012000China Department of Mathematics Inner Mongolia University of TechnologyHohhot010051China Institute of Economics and Management Jining Normal UniversityJining012000China

Although some numerical methods of the fractional-order chaotic systems have been announced,high-precision numerical methods have always been the direction that researchers strive to *** on this problem,this paper introduces a high-precision numerical *** complex dynamic behavior of fractional-order Lorenz chaotic systems are shown by using the present *** observe some novel dynamic behavior in numerical experiments which are unlike any that have been previously discovered in numerical experiments or theoretical *** investigate the influence of α_(1),α_(2),α_(3) on the numerical solution of fractional-order Lorenz chaotic *** simulation results of integer order are in good agreement with those of *** simulation results of numerical experiments demonstrate the effectiveness of the present method.

关键词： Novel complex dynamic behavior numerical simulation fractional-order lorenz chaotic systems high-precision