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Fast Determination of Phenanthrene in Soil by Gas Chroma- tography-Mass Spectrometry Using Chemometric Resolution and Standard Addition Method

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Chinese Journal of Chemistry 2013年第4期31卷 545-550页

作者： Weiwei yu Wensheng Cai Xueguang shao State Key Laboratory of Medicinal Chemical Biology Research Center for Analytical Sciences College of Chemistry Nankai University Tianjin 300071 China

A method for fast determination of the component in complex samples by using gas chromatography-mass spectrometry （GC-MS） was developed and used for quantitative analysis of phenanthrene in soils. In the method, window independent component analysis （WICA） was used for resolving the mass spectrum and non-negative im- mune algorithm （NNIA） was employed for obtaining the chromatographic profile. Therefore, spectral and chroma- tographic information of a specific component can be obtained from the measured GC-MS data of overlapping and high background. Six soil samples collected from different places were analyzed. The tedious pretreatments in pre- paring the samples and the elution in the separation were simplified for speeding up the analysis. Due to the com- plexity of the matrix, standard addition method was adopted for the final quantification. The applicability of the method was validated with a spiked sample and the results of the six samples are reasonable.

关键词： phenanthrene gas chromatography-mass spectrometry standard addition method chemoinformatics immune algorithm

Low-temperature synthesis of sp^2 carbon nanomaterials

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Science Bulletin 2019年第24期64卷 1817-1829页

作者： yu Ding Mengqi Zeng Lei fu College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China The Institute for Advanced Studies Wuhan UniversityWuhan 430072China

sp^2 carbon nanomaterials are mainly composed of sp^2-hybridized carbon atoms in the form of a hexagonal network. Due to the p bonds formed by unpaired electrons, sp^2 carbon nanomaterials possess excellent electronic, mechanical, and optical properties, which have attracted great attention in recent *** the advanced sp^2 carbon nanomaterials, graphene and carbon nanotubes(CNTs) have great potential in electronics, sensors, energy storage and conversion devices, etc. The low-temperature synthesis of graphene and CNTs are indispensable to promote the practical industrial application. furthermore, graphene and CNTs can even be expected to directly grow on the flexible plastic that cannot bear high temperature,expanding bright prospects for applications in emerging flexible nanotechnology. An in-depth understanding of the formation mechanism of sp^2 carbon nanomaterials is beneficial for reducing the growth temperature and satisfying the demands of industrial production in an economical and low-cost way. In this review, we discuss the main strategies and the related mechanisms in low-temperature synthesis of graphene and CNTs, including the selection of precursors with high reactivity, the design of catalyst, and the introduction of additional energy for the pre-decomposition of precursors. furthermore, challenges and outlooks are highlighted for further progress in the practical industrial application.

关键词： Low-temperature synthesis sp^2 carbon nanomaterials Graphene Carbon nanotubes

A Complex Network Model for Analyzing Railway Accidents Based on the Maximal Information Coefficient

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Communications in Theoretical Physics 2016年第10期65卷 459-466页

作者： fu-Bo shao Ke-Ping Li State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University

It is an important issue to identify important influencing factors in railway accident *** this paper,employing the good measure of dependence for two-variable relationships,the maximal information coefficient(MIC),which can capture a wide range of associations,a complex network model for railway accident analysis is designed in which nodes denote factors of railway accidents and edges are generated between two factors of which MIC values are larger than or equal to the dependent *** variety of network structure is *** the increasing of the dependent criterion,the network becomes to an approximate scale-free ***,employing the proposed network,important influencing factors are *** we find that the annual track density-gross tonnage factor is an important factor which is a cut vertex when the dependent criterion is equal to *** the network,it is found that the railway development is unbalanced for different states which is consistent with the fact.

关键词： railway accidents complex network the maximal information coefficient

STABILITY ANALYSIS OF RUNGE-KUTTA METHODS FOR NONLINEAR SYSTEMS OF PANTOGRAPH EQUATIONS

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Journal of Computational Mathematics 2005年第4期23卷 351-356页

作者： yue-xin yu Shou-fu Li Department of Mathematics Xiangtan University Xiangtan 411105 China

This paper is concerned with numerical stability of nonlinear systems of pantograph equations. Numerical methods based on （k, l）-algebraically stable Runge-Kutta methods are suggested. Global and asymptotic stabilit... 详细信息

关键词： Nonlinear pantograph equations Runge-Kutta methods Numerical stability Asymptotic stability

Simulation of underexpanded supersonic jet flows with chemical reactions

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Chinese Journal of Aeronautics 2014年第3期27卷 505-513页

作者： fu Debin yu Yong Niu Qinglin School of Aerospace Engineering Beijing Institute of Technology

To achieve a detailed understanding of underexpanded supersonic jet structures influenced by afterburning and other flow conditions, the underexpanded turbulent supersonic jet with and without combustions are investigated by computational fluid dynamics （CFD） method. A program based on a total variation diminishing （TVD） methodology capable of predicting complex shocks is created to solve the axisymmetric expanded Navie^Stokes equations containing transport equations of species. The finite-rate ratio model is employed to handle species sources in chemical reactions. CFD solutions indicate that the structure of underexpanded jet is typically influenced by the pressure ratio and afterburning. The shock reflection distance and maximum value of Mach number in the first shock cell increase with pressure ratio. Chemical reactions for the rocket exhaust mostly exist in the mixing layer of supersonic jet flows. This tends to reduce the intensity of shocks existing in the jet, responding to the variation of thermal parameters.

关键词： Combustion Finite-rate model Numerical simulation TVD method Underexpanded jet

Integrated lifting line/surface panel method for optimal propeller design with consideration of hub effect

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Journal of Hydrodynamics 2019年第6期31卷 1218-1230页

作者： Wen-yu Sun Guo-fu Huang China Ship Scientific Research Center Wuxi 214082China

An optimal marine propeller design method is proposed,which integrates the lifting line and surface panel method and is characterized by the use of the surface panel method to take the hub effect into *** developing an integrated approach instead of an iterative method for the calculation of the interaction between the hub and the designed blades,the hub effects on the optimal circulation can be accounted for throughout the theoretical design *** new integrated method provides a fast and accurate enough method to model the straight forward hub surface,in the optimal propeller design.A systematic design procedure from the basic design inputs to the blade geometry determination is performed and the designed propellers are validated by the surface panel method and the RANS *** design and analysis cases are considered by different approaches with comparison and *** a comparative study including different hub geometries is also performed to reveal the mechanism of the hub effect on the distributions of the propeller optimal loads.

关键词： Optimal circulation design lifting line method surface panel method hub effect

The Silk Textile Embedded in Silk Fibroin Composite: Preparation and Properties

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Chinese Journal of Polymer Science 2018年第9期36卷 1043-1046页

作者： yu Duan Xin Chen Zheng-Zhong shao State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular Science Laboratory of Advanced Materials Fudan University

Silk reinforced silk-fibroin-based composites were prepared by embedding of silk textile into regenerated silk fibroin （RSF） matrix. The breaking stress and breaking strain of the composites were found 37.7 MPa and 71.1% respectively at （95 ：t： 5）% RH. Morphological analysis was carried out to observe fracture behavior of the samples. The in vitro biodegradation test showed that the composite degraded slowly and lost 70% weight at the end of 168 h. Moreover, compared with RSF pure film, the composite kept strength and toughness much longer time. In conclusion, this composite has the potential for more accurate cytology research and biomedical tests in the future.

关键词： Silk protein Biomaterials Composite Mechanical properties Natural product

Photoinduced palladium-catalyzed 1,3-diene-selective fluoroalkylamination compounds as potential bactericidal agent against Xanthomonas oryzae ***

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Chinese Chemical Letters 2024年第1期35卷 401-405页

作者： yu Shi Zhao-Sheng Zhang Jiang shao Chen fu Lan-Tu Xiong Zhao-Dong Li Zi-Ning Cui National Key Laboratory of Green Pesticide Integrative Microbiology Research CentreGuangdong Province Key Laboratory of Microbial Signals and Disease ControlCollege of Plant ProtectionSouth China Agricultural UniversityGuangzhou 510642China Henry Fok School of Biology and Agriculture Shaoguan UniversityShaoguan 512005China College of Materials and Energy South China Agricultural UniversityGuangzhou 510642China

A series of photoinduced palladium-catalyzed 1,3-diene-selective fluoroalkylamination derivatives was rationally synthesized based on diversity-oriented synthesis via cross coupling of 1,3-dienes,amines and fluoroalkyl *** reaction featured good function group tolerance and a broad substrate scope,which could be extended to the late-stage modification of bioactive *** activity of all the compounds against Xanthomonas oryzae ***(Xoo)was *** them,compound E14 showed significant activity against Xanthomonas oryzae ***(Xoo)with half maximal effective concentration(EC50)value of 6.61μmol/*** pot experiments,the results showed that E14 could control rice bacterial blight with protective and curative efficiencies of 37.5%and 63.2%at 200μg/mL,***,a plausible mechanism for antibacterial behavior of E14 was proposed by electron microscopy,flow cytometry,reactive oxygen species detection,and biofilm *** current work,it can promote the development of photoinduced palladium-catalyzed 1,3-diene-selective fluoroalkyl amination compounds as prospective antibacterial agent bearing an intriguing mode of action.

关键词： 1,3-Diene-selective fluoroalkylamination derivatives Xanthomonas oryzae pv.oryzae Antibacterial activity Electron microscopy Reactive oxygen Flow cytometry

Long-term thermal-aging stability of oxide-dispersion-strengthened ferritic steels at 753 K

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Journal of Iron and Steel Research International 2018年第7期25卷 776-784页

作者： Shuai Xu Zhang-jian Zhou shao-fu Li Hao-dong Jia School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Oxide-dispersion-strengthened （ODS） ferritic steels are promising candidates for structural applications in the future nuclear reactors. The higher chromium contents of ODS ferritic steels, the better the corrosion resistance, which can meet the harsh corrosion environment of the advanced reactors. However, increasing the Cr content may also lead to the brittleness of the ODS steels when serving at high temperatures. The ODS ferritic steels with different Cr contents （12, 16 and 18 wt% Cr, respectively） were fabricated by mechanical alloying, hot isostatic pressing and forging. Mechanical properties and microstructure evolution of the ODS ferritic steels after aging at 753 K for 2000 h were investigated. It is found that both Vickers hardness and yield strength of 18%Cr ODS ferritic steel were strongly increased and the impact energy was decreased after aging at 753 K. In order to explore the reasons for changes in the mechanical properties, the fracture surfaces were characterized by scanning electron microscopy, and microstructures after aging were observed by transmission electron microscopy. The impact fracture of 18%Cr ODS ferritic steel belongs to quasi-cleavage facture, which is consistent with its very low impact energy. The grain size and dispersed oxide particles of different ODS steels are very stable. M23C6 carbide and M2C carbide were found in 12%Cr ODS steel and 16%Cr ODS steels, respectively.

关键词： Oxide-dispersion-strengthened ferritic steel Aging stability - Mechanical property Microstructure