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CONTINUOUS STIFFNESS MODE NANOINDENTATION RESPONSE OF POLY(METHYL METHACRYLATE) SURFACES

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Chinese journal of Polymer Science 2013年第8期31卷 1096-1107页

作者： T. Iqbal B.j. Briscoe S. Yasin P.F. Luckham Chemical Engineering Department University of Engineering & Technology Chemical Engineering Department Imperial College

Indentation is a comparatively simple and virtually nondestructive method of determining mechanical properties of material surfaces by means of an indenter inducing a localized deformation. The paper present experimental results of the load-displacement curves, the hardness and the elastic modulus data, and associated analysis for poly（methyl methacrylate）（PMMA） surfaces as a function of contact displacement. The experimental results include continuous stiffness indentations performed using constant loading rate and constant displacement rate experiments. The continuous stiffness indentation involves continuous calculation of a material stiffness, and hence hardness and elastic modulus of surfaces, during discrete loading-unloading cycles, as in a conventional indentation routine, and in a comparatively smaller time constant, The dependence of the compliance curves, the hardness, the elastic modulus and the plasticity index upon the imposed penetration depth, the applied normal load and the deformation rate are described. Tip area and load frame calibrations for the continuous stiffness indentation are also reported. The paper includes practical considerations encountered during indentation of polymers specifically at low penetration depths. The experimental results show a peculiarly harder response of PMMA surfaces at the submicron （near to surface） layers.

关键词： Nanoindentation PMMA Hardness Modulus Continuous stiffness.

Inductively coupled plasma emission spectroscopic and flame photometric analysis of goat epididymal fluid

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Asian journal of Andrology 2000年第4期2卷 288-292页

作者： Meenakshi Gaur Vikas Pruthi Ramasare Prasad Ben M.j.Pereira Reproductive Biology Laboratory Dept. of Bioscience and Biotechnology University of Roorkee Roorkee-247 667 U. P. IndiaReproductive Biology Laboratory Dept. of Bioscience and Biotechnology University of Roorkee Roorkee-247 667 U. P. IndiaReproductive Biology Laboratory Dept. of Bioscience and Biotechnology University of Roorkee Roorkee-247 667 U. P. IndiaReproductive Biology Laboratory Dept. of Bioscience and Biotechnology University of Roorkee Roorkee-247 667 U. P. India

Aim: The elemental composition of the epididymal luminal fluid (ELF) in adult goat ( Capra indica) was investigat-ed. Methods: ELF was collected by micropuncture from twelve sites along the epididymal duct. The elementalcontents was analyzed with inductively coupled plasma (ICP) emission spectroscopy, a microanalytical technique thatcan simultaneously measure many elements in minute volumes of sample. The Na and K concentrations were determinedby flame photometry. Results: ICP spectroscopy showed the presence of copper, calcium, nickel, iron, magne-sium, chromium, titanium and zinc in ELF, with fluctuating levels at different sites along the length of the ***, cobalt, lead and manganese were not fotmd. The Na^+ / K^+ ratio was seen to be higher at the initial seg-ments of the epididymis and lower at the distal. Conclusion: It is proposed that the observed characteristic distribu-tion of elements in ELF may have far reaching implications in sperm maturation and storage known to occur in the epi-didymis. (Asian j Androl 2000 Dec; 2: 288-292)

关键词： goat epididymis epididymal luminal fluid elements spectroscopy flame photometry

Spin and pseudospin symmetries of the Dirac equation with shifted Hulthe′n potential using supersymmetric quantum mechanics

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Chinese Physics B 2013年第12期22卷 74-81页

作者： Akpan N. Ikot Elham Maghsoodi Eno j. Ibanga Saber Zarrinkamar Hassan Hassanabadi Theoretical Physics Group Department of Physics University of Uyo-Nigeria Department of Basic Sciences Shahrood Branch Islamic Azad University Department of Basic Sciences Garmsar Branch Islamic Azad University

In this paper, we obtain approximate analytical solutions of the Dirac equation for the shifted Hulthén potential within the framework of spin and pseudospin symmetry limits for arbitrary spin–orbit quantum number κ using the supersymmetry quantum mechanics. The energy eigenvalues and the corresponding Dirac wave functions are obtained in closed forms.

关键词： Dirac equation supersymmetry method spin and pseudospin symmetries shifted Hulthén potential

Deductive way of reasoning about the internet AS level topology

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Chinese Physics B 2015年第11期24卷 633-642页

作者： Dávid Szabó Attila Korsi józsef Bíró András Gulyás High Speed Networks Laboratory Budapest University of Technology and Economics MTA-BME Information Systems Research Group Budapest University of Technology and Economics MTA-BME Future Internet Research Group Budapest University of Technology and Economics

Our current understanding about the AS level topology of the Internet is based on measurements and inductive-type models which set up rules describing the behavior （node and edge dynamics） of the individual ASes and generalize the consequences of these individual actions for the complete AS ecosystem using induction. In this paper we suggest a third, deductive approach in which we have premises for the whole AS system and the consequences of these premises are determined through deductive reasoning. We show that such a deductive approach can give complementary insights into the topological properties of the AS graph. While inductive models can mostly reflect high level statistics （e.g., degree distribution, clustering, diameter）, deductive reasoning can identify omnipresent subgraphs and peering likelihood. We also propose a model, called YEAS, incorporating our deductive analytical findings that produces topologies contain both traditional and novel metrics for the AS level Internet.

关键词： internet topology complex network analysis model

Two-component modeling for non-Newtonian nanofluid slip flow and heat transfer over sheet: Lie group approach

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Applied Mathematics and Mechanics(English Edition) 2016年第10期37卷 1325-1340页

作者： P.RANA M.j.UDDIN Y.GUPTA A.I.M.ISMAIL Department of Mathematics Jaypee Institute of Information Technology School of Mathematical Sciences Universiti Sains Malaysia Department of Mathematics American International University-Bangladesh

The present paper deals with the multiple solutions and their stability analy- sis of non-Newtonian micropolar nanofluid slip flow past a shrinking sheet in the presence of a passively controlled nanoparticle boundary condition. The Lie group transformation is used to find the similarity transformations which transform the governing transport equations to a system of coupled ordinary differential equations with boundary condi- tions. These coupled set of ordinary differential equation is then solved using the Runge- Kutta-Fehlberg fourth-fifth order （RKF45） method and the ode15s solver in MATLAB. For stability analysis, the eigenvalue problem is solved to check the physically realizable solution. The upper branch is found to be stable, whereas the lower branch is unsta- ble. The critical values （turning points） for suction （0 〈 sc 〈 s） and the shrinking parameter （Xc 〈 X 〈 0） are also shown graphically for both no-slip and multiple-slip conditions. Multiple regression analysis for the stable solution is carried out to inves- tigate the impact of various pertinent parameters on heat transfer rates, The Nusselt number is found to be a decreasing function of the thermophoresis and Brownian motion parameters.

关键词： micropolar nanofluid stability multiple-slip Lie group MATLAB

PARALLEL ANALYSIS OF COMBINED FINITE/DISCRETE ELEMENT SYSTEMS ON PC CLUSTER

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Acta Mechanica Sinica 2004年第5期20卷 534-540页

作者：王福军 Y.T.FENG D.R.j.OWEN 张静刘洋 College of Water Conservancy & Civil Eng. China Agricultural UniversityBeijing 100083China Civil & Computational Engineering Centre University of Wales SwanseaSwanseaSA2 8PPU.K.

A computational strategy is presented for the nonlinear dynamic analysis of large- scale combined finite/discrete element systems on a PC *** this strategy,a dual-level domain decomposition scheme is adopted to implement the dynamic domain *** domain decomposition approach perfectly matches the requirement of reducing the memory size per processor of the *** treat the contact between boundary elements in neighbouring subdomains,the elements in a subdomain are classified into internal,interfacial and external *** this way,all the contact detect algorithms developed for a sequential computation could be adopted directly in the parallel *** examples show that this implementation is suitable for simulating large-scale *** typical numerical examples are given to demonstrate the parallel efficiency and scalability on a PC cluster.

关键词： parallel computation finite element discrete element PC cluster

Two-Factor Cancelable Biometrics Authenticator

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journal of Computer Science & Technology 2007年第1期22卷 54-59页

作者：彭颖涵 Andrew T. B. j David N. C. L Faculty of Information Science and Technology Multimedia University dalan Ayev Keroh Lama 75450 Melaka Malaysia

Biometrics-based authentication system offers advantages of providing high reliability and accuracy. However the contemporary authentication system is impuissance to compromise. If a biometrics data is compromised, it cannot be replaced and rendered unusable. In this paper, a cancelable biometrics-based authenticator is proposed to solve this irrevocability issue. The proposed approach is a two-factor authentication system, which requires both of the random data and facial feature in order to access the system. In this system, tokenized pseudo-random data is coupled with momentbased facial feature via inner product algorithm. The output of the product is then discretized to generate a set of private binary code, coined as 2factor-Hashing code, which is acted as verification key. If this biometrics-based verification key is compromised, a new one can be issued by replacing a different set of random number via token replacement. Then, the compromised one is rendered completely useless. This feature offers an extra protection layer against biometrics fabrication since the verification code is replaceable. Experimental results demonstrate that the proposed system provides zero Equal Error Rate in which there is a clear separation in between the genuine and the imposter distribution populations.

关键词： cancelable biometrics face recognition Geometric moments,pseudo Zernike moment

APPLICATION OF HIGH PRESSURE LIQUID CHROMATOGRAPHY AND MICROSEQUENCING METHODOLOGY IN THE STRUCTURAL ANALYSIS OF HUMAN HEMOGLOBIN VARIANTS

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Science China Chemistry 1983年第08期26卷 836-849页

作者：曾溢滔,黄淑帧,A.REYNOLDS,H.LAM,B.B.WEBBER,j.B.WILSON,T.H.j.HUISMAN Laboratory of Medical Genetics Shanghai Children's Hospital Shanghai People's Republic of China Laboratory of Medical Genetics Shanghai Children's Hospital Shanghai People's Republic of China Laboratory of Protein Chemistry Comprehensive Sickle Cell Center Department of Cell and Molecular Biology Medical Collge of Georgia Augusta Ga 30912 U. S. A. Laboratory of Protein Chemistry Comprehensive Sickle Cell Center Department of Cell and Molecular Biology Medical Collge of Georgia Augusta Ga 30912 U. S. A. Laboratory of Protein Chemistry Comprehensive Sickle Cell Center Department of Cell and Molecular Biology Medical Collge of Georgia Augusta Ga 30912 U. S. A. Laboratory of Protein Chemistry Comprehensive Sickle Cell Center Department of Cell and Molecular Biology Medical Collge of Georgia Augusta Ga 30912 U. S. A. Laboratory of Protein Chemistry Comprehensive Sickle Cell Center Department of Cell and Molecular Biology Medical Collge of Georgia Augusta Ga 30912 U. S. A.

This paper reports the results of the analyses of 17 different Hb variants which were observed in 37 families. High pressure liquid chromatography (HPLC) was used to separate tryptic and thermolytic peptides of globin chains. The double coupling microsequencing technique can successfully be used for sequencing small or larger peptides.

关键词： APPLICATION OF HIGH PRESSURE LIQUID CHROMATOGRAPHY AND MICROSEQUENCING METHODOLOGY IN THE STRUCTURAL ANALYSIS OF HUMAN HEMOGLOBIN VARIANTS HPLC

Study of engine performance, emission and combustion characteristics fueled with diesel-like fuel produced from waste engine oil and waste plastics

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Frontiers of Environmental Science & Engineering 2018年第4期12卷 77-85页

作者： V. Edwin Geo Ankit Sonthalia Fethi AIoui Femilda josephin j. S. Department of Automobile Engineering SRM Institute of Science and Technology Kattankulathur-603203 India Department of Mechanical and Automobile Engineering SRM Institute of Science and Technology NCR Campus~ Modinagar-201204 India Campus Mont Houy F-5931 LAMIH UMR CNRS 8201 Department of Mechanical Engineering University of Valenciennes (UVHC) Campus Mont-Houy F-59313 Valenciennes Cedex 9 France Department of Software Engineering SRM Institute of Science and Technology Kattankulathur-603203 India

Utilizing oil extracted from waste engine oil and waste plastics, by pyrolysis, as a filel for internal combustion engines has been demonstrated to be one of the best available waste management methods. Separate blends of fuel from waste engine oil and waste plastic oil was prepared by mixing with diesel and experimental investigation is conducted to study engine performance, combustion and exhaust emissions. It is observed that carbon monoxide （CO） emission increases by 50% for 50% waste plastic oil （50WPO：50D） and by 58% for 50% waste engine oil （50WEO：50D） at full load as compared to diesel. Unburnt hydrocarbon （HC） emission increases by 16% for 50WPO：50D and by 32% for 50WEO：50D as compared to diesel at maximum load. Smoke is fotmd to decrease at all loading conditions for 50WPO：50D operation, but it is comparatively higher for 50WEO：50D operation. 50WPO：50D operation shows higher brake thermal efficiency for all loads as compared to 50WEO：50D and diesel fuel operation. Exhaust gas temperature is higher at all loads tbr 50WPO：50D and 50WEO：50D as compared to diesel fuel operation.

关键词： Waste engine Oil Waste plasti Oil Diesel fuelPyrolysis Compression engine