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Correlation Between Energy Transfer Rate and Atomization Energy of Some Trinitro Aromatic Explosive Molecules

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Chinese Journal of Chemical Physics 2008年第3期21卷 250-254页

作者： Su-hong Ge Xin-lu Cheng Zheng-lai Liu Xiang-dong Yang fang-fang dong Department of Physics Hexi University Zhangye 734000 China Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China

An assumptive theoretical relationship is suggested to describe the property of molecular atomization energy and energy transfer rate in the initiation of explosions. To investigate the relationship between atomization energy and energy transfer rate, the number of doorway modes of explosives is estimated by the theory of Dlott and Fayer in which the rate is proportional to the number of normal mode vibrations. It was evaluated frequencies of normal mode vibrations of eight molecules by means of density functional theory （DFT） at the b3p86/6-31G（d,p） level. It is found that the number of doorway modes shows a linear correlation to the atomization energies of the molecules, which were also calculated by means of the same method. A mechanism of this correlation is discussed. It is also noted that in those explosives with similar molecular structure and molecular weight, the correlation between the atomization energy and the number of doorway modes is higher.

关键词： Secondary explosive Atomization energy Normal mode vibration Doorway region

Microstructure and phase transformation of Ni_(56)Fe_(x)Ga_(44-x)(15≤x≤20)alloys

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Rare Metals 2024年第11期43卷 6048-6053页

作者： Cui-fang dong Jing-Min Wang Laboratory of Aerospace Materials and Performance(Ministry of Education) School of Materials Science and EngineeringBeihang UniversityBeijing 100191China

Ni_(56)Fe_(x)Ga_(44-x)(15≤x≤20)alloys were studied with the phase structure and magnetic *** martensitic transformation was observed over the whole composition *** martensitic transformation starting temperature(M_(s))increases from 256 K for x=15 to 350 K for x=18 and then decreases from 350 K for x=18 to333 K for x=20 by increasing substitution of Fe for *** austenitic Curie temperature((?))is observed for15≤x≤16 and 18≤x≤20,*** the martensitic Curie temperature(T^(A)_(X))is observed for x=*** 18

关键词： Ni-Fe-Ga Dual-phase Martensitic transformation Magnetic transition

Performance Analysis of Hybrid Distribution in Human-Centric Multimedia Networking

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Chinese Journal of Electronics 2016年第4期25卷 761-767页

作者： HU Yuxiang dong fang LAN Julong National Digital Switching System Engineering and Technological Research Center

With the booming of Human-centric multimedia networking(HMN),there are rising amount of human-made multimedia that needs to distribute to consumers with higher speed and *** distribution of Client/Server(C/S) and Peer-to-Peer(P2P) have been successfully deployed on the Internet and the practical benefits have been widely reported,while its theoretical performance remains unknown for mass data delivery *** paper presents an analytical and experimental study on the performance of accelerating large-scale hybrid distribution over the *** particular,this paper focuses on the user behavior in HMN and establishes a user behavior model based on the Kermack-McK endrick model in *** expressions of average delay in HMN are then derived based on C/S,P2 P and hybrid distribution,*** simulation shows how to design and deploy a hybrid distribution system of HMN that helps to bridge the gap between system ultilization and quality of service,which provides direct guidance for practical system design.

关键词： Hybrid distribution Peer-to-peer Client/server Behaviour model Performance analysis

Udwadia–Kalaba Equation for Constrained Mechanical Systems:Formulation and Applications

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Chinese Journal of Mechanical Engineering 2018年第6期31卷 11-24页

作者： Xiao-Min Zhao Ye-Hwa Chen Han Zhao fang-fang dong School of Automotive and Transportation Engineering Hefei University of TechnologyHefei 230009China The George W.Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlanta 30332USA School of Mechanical Engineering Hefei University of TechnologyHefei 230009China

There are many achievements in the field of analytical mechanics, such as Lagrange Equation, Hamilton’s Principle, Kane’s Equation. Compared to Newton–Euler mechanics, analytical mechanics have a wider range of applications and the formulation procedures are more mathematical. However, all existing methods of analytical mechanics were proposed based on some auxiliary variables. In this review, a novel analytical mechanics approach without the aid of Lagrange’s multiplier, projection, or any quasi or auxiliary variables is introduced for the central problem of mechanical systems. Since this approach was firstly proposed by Udwadia and Kalaba, it was called Udwadia–Kalaba Equation. It is a representation for the explicit expression of the equations of motion for constrained mechanical systems. It can be derived via the Gauss’ s principle, d’Alembert’s principle or extended d’Alembert’s principle. It is applicable to both holonomic and nonholonomic equality constraints, as long as they are linear with respect to the accelerations or reducible to be that form. As a result, the Udwadia–Kalaba Equation can be applied to a very broad class of mechani?cal systems. This review starts with introducing the background by a brief review of the history of mechanics. After that, the formulation procedure of Udwadia–Kalaba Equation is given. Furthermore, the comparisons of Udwadia–Kalaba Equation with Newton–Euler Equation, Lagrange Equation and Kane’s Equation are made, respectively. At last, three di erent types of examples are given for demonstrations.

关键词： Udwadia–Kalaba Equation Mechanical system Constraint Moore–Penrose inverse

A Hybrid Unsupervised Clustering-Based Anomaly Detection Method

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Tsinghua Science and Technology 2021年第2期26卷 146-153页

作者： Guo Pu Lijuan Wang Jun Shen fang dong School of Cyber Engineering Xidian UniversityXi'an 710126China School of Computing and Information Technology University of WollongongNSW 2522Australia School of Computer Science and Engineering Southeast UniversityNanjing 211189China

In recent years,machine learning-based cyber intrusion detection methods have gained increasing *** number and complexity of new attacks continue to rise;therefore,effective and intelligent solutions are *** machine learning techniques are particularly appealing to intrusion detection systems since they can detect known and unknown types of attacks as well as zero-day *** the current paper,we present an unsupervised anomaly detection method,which combines Sub-Space Clustering(SSC)and One Class Support Vector Machine(OCSVM)to detect attacks without any prior *** proposed approach is evaluated using the well-known NSL-KDD *** experimental results demonstrate that our method performs better than some of the existing techniques.

关键词： unsupervised learning clustering intrusion detection feature selection

Recent advances of variational model in medical imaging and applications to computer aided surgery

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Applied Mathematics(A Journal of Chinese Universities) 2012年第4期27卷 379-411页

作者： PENG Jia-lin dong fang-fang KONG De-Xing Center of Mathematical Sciences Zhejiang UniversityHangzhou 310027China School of Statistics and Mathematics Zhejiang Gongshang UniversityHangzhou 310027China Department of Mathematics Zhejiang UniversityHangzhou 310027China

In this paper, we review some mathematical models in medical image processing. Due to the superiority in modeling and computation, variational methods have been proven to be powerful techniques, which have been extremely popular and dramatically improved in the past two decades. On one hand, many models have been proposed for nearly all kinds of applications. On the other hand, a lot of models can be globally optimized and also many computation tools have been introduced. Under the variational framework, we focus on two basic problems in medical imaging： image restoration and segmentation, which are core components for kinds of specific tasks. For image restoration, we discuss some models on both additive and multiplicative noises. For image segmentation, we review some models on both whole image segmentation and specific target delineation, with the later being a key step in computer aided surgery. Additionally, we present some models on liver delineation and give their applications to living donor liver transplantation.

关键词： segmentation restoration variational model computer aided surgery.

Construction,Expression and Purification of SUMO1-GST Fusion Protein

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Chemical Research in Chinese Universities 2011年第2期27卷 245-248页

作者： QIAO Xiao-fang fang Xue-dong LIU Jun The Second Hospital of Jilin University Changchun 130041 P. R.China

Sumoylation is an important protein modification discovered recently. SUMO（small ubiquitin-related modifier） pathway regulates the protein stability and transcriptional activity with a 12-kDa small molecular protein, SUMO, ligated to the target protein. The purification of SUMO proteins is a key step to reveal their function. The purpose of this study was to construct the recombinant SUMO1 gene cloned to a pGEX-4T-1 vector to express and purify the SUMO1-GST fusion protein in Escherichia coli. First, the full length DNA sequence of SUMO1 gene was amplified by PCR and was ligated to pMD18-T vector. Then the SUMO1 gene was subcloned to pGEX-4T-1 prokaryotic expression vector between BamHI and XhoI sites, and transformed in Escherichia coli DH5α cells. The right colonies were identified by restrictive enzyme digestion and sequencing. The correct rebombinant plasmid of pGEX-4T-1-SUMO1 was transformed in Escherichia coli BL21 cells and then induced by IPTG（isopropyl- β-D-1- thiogalacto-pyranoside） to express the SUMO1-GST fusion protein. The highly purified SUMO1-GST（glutathione S-transferase） fusion protein was obtained by affinity chromatography. Finally, the properties of SUMO1-GST fusion protein were confirmed by Coomassie brilliant blue strain and Western blot analysis. The recombinant plasmid of pGEX-4T-1-SUMO1 was successfully constructed, and SUMO1-GST fusion proteins were successfully expressed.

关键词： Small ubiquitin-related modifier 1 (SUMO1) Gutathione S-transferase(GST) fusion protein Affinity chromatography

Synergistic Action between Jasmonic Acid and Nitric Oxide in Inducing Matrine Accumulation of Sophora flavescens Suspension Cells

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Journal of Integrative Plant Biology 2008年第1期50卷 92-101页

作者： Mao-Jun Xu Ju-fang dong Department of Biotechnology Zhejiang Gongshang University Hangzhou 310035 China

Secondary metabolites not only play important ecological roles in plants but also are important pharmaceutical and source compounds for derivative synthesis. Production of plant secondary metabolites is believed to be controlled by the endogenous signal network of plants. However, the molecular basis is still largely unknown. Here we show that matrine production of Sophora flavescens Ait. cells treated with low levels of jasmonic acid （JA） and nitric oxide （NO） is significantly increased although treatment with low concentrations of JA or NO alone has no effects on matrine production, showing that JA and NO may act synergistically in triggering matrine production. Moreover, treatment with NO triggers lipoxygenase （LOX） activity and enhances JA levels of the cells, showing that NO may activate the endogenous JA biosynthesis of S. flavescens cells. External application of JA induces nitric oxide synthase-like activities and stimulates NO generation of S. flavescens cells, which suggests that JA may trigger NO generation of the cells. Thus, the results reveal a mutually amplifying reaction between JA and NO in S. flavescens cells. Furthermore, JA and NO inhibitors suppress not only the mutually amplifying reaction between JA and NO but also the synergistic effects of NO and JA on matrine production. Therefore, the data demonstrate that the synergistic action of JA and NO in inducing matrine production might be due to the mutually amplifying reaction between JA and NO in the cells.

关键词： jasmonic acid nitric oxide matrine Sophora flavescens cells.

A Comparison of Conventional and Shear-Rate Dependent Mohr-Coulomb Models for Simulating Landslides

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Journal of Mountain Science 2014年第6期11卷 1478-1490页

作者： LIANG dong-fang HE Xu-zhen MOE Key Laboratory of Hydrodynamics Shanghai Jiao Tong University Department of Engineering University of Cambridge Trumpington StreetCambridge CB2 1PZ UK

Landslides may cause many fatalities and heavy economic losses,so it is vital to understand their mechanics so as to take appropriate measures to mitigate their ***,the loose soil behaves like frictional material in most circumstances,so Mohr-Coulomb type equations are often used to describe their ***,these models generally do not consider the influence of the shearrate on the Mohr-Coulomb friction angle,so the shear-rate dependence effect on the soil flow and landslide runout is not well *** paper reports on an application of the incompressible Smoothed Particle Hydrodynamics(SPH) method to the dynamics of dry granular *** traditional model with a constant friction angle is compared with the modified Mohr-Coulomb model with a variable friction angle related to the *** is found that the shear-rate dependence effect is negligible for shallow granular flows along mild *** steeper slopes of the ground and larger aspect ratios of the initial soil column,the rate-dependence effect becomes more important.

关键词： Landslides Granular flows MohrCoulomb model Smoothed Particle Hydrodynamics