WorldWideScience

Sample records for non-metallic semi-flexible low-modulus

  1. Semi-flexible sockets for amputation below the knee.

    Science.gov (United States)

    Symington, D C; Lowe, P J; Mackay, S

    1975-09-01

    A semi-flexible socket fitted to a series of 47 consecutive below-knee amputees is evaluated, and the problems in assessing prosthetic components and appropriate methodology are discussed. The results suggest that this type of socket deserves wider use and further evaluation in active amputees, where comfort, perspiration control or the condition of the skin is interfering with the patient's function.

  2. Bending dynamics of semi-flexible macromolecules in isotropic turbulence

    CERN Document Server

    Ali, Aamir; Vincenzi, Dario

    2014-01-01

    We study the Lagrangian dynamics of semi-flexible macromolecules in laminar as well as in homogeneous and isotropic turbulent flows by means of analytically solvable stochastic models and direct numerical simulations. The statistics of the bending angle is qualitatively different in laminar and turbulent flows and exhibits a strong dependence on the topology of the velocity field. In particular, in two-dimensional turbulence, particles are either found in a fully extended or in a fully folded configuration; in three dimensions, the predominant configuration is the fully extended one.

  3. Semi-flexible bimetal-based thermal energy harvesters

    CERN Document Server

    Boisseau, S; Monfray, S; Puscasu, O; Skotnicki, T; 10.1088/0964-1726/22/2/025021

    2013-01-01

    This paper introduces a new semi-flexible device able to turn thermal gradients into electricity by using a curved bimetal coupled to an electret-based converter. In fact, a two-steps conversion is carried out: (i) a curved bimetal turns the thermal gradient into a mechanical oscillation that is then (ii) converted into electricity thanks to an electrostatic converter using electrets in Teflon (r). The semi-flexible and low cost design of these new energy converters pave the way to mass production over large areas of thermal energy harvesters. Raw output powers up to 13.46uW per device were reached on a hot source at 60{\\deg}C and forced convection. Then, a DC-to-DC flyback converter has been sized to turn the energy harvesters' raw output powers into a viable supply source for an electronic circuit (DC-3V). At the end, 10uW of directly usable output power were reached with 3 devices, which is compatible with Wireless Sensor Networks powering applications. Please cite as : S Boisseau et al 2013 Smart Mater. S...

  4. Non-equilibrium fluctuations of a semi-flexible filament driven by active cross-linkers

    CERN Document Server

    Weber, Ines; Schehr, Grégory; Santen, Ludger

    2016-01-01

    The cytoskeleton is an inhomogeneous network of semi-flexible filaments, which are involved in a wide variety of active biological processes. Although the cytoskeletal filaments can be very stiff and embedded in a dense and cross-linked network, it has been shown that, in cells, they typically exhibit significant bending on all length scales. In this work we propose a model of a semi-flexible filament deformed by different types of cross-linkers for which one can compute and investigate the bending spectrum. Our model allows to couple the evolution of the deformation of the semi-flexible polymer with the stochastic dynamics of linkers which exert transversal forces onto the filament. We observe a $q^{-2}$ dependence of the bending spectrum for some biologically relevant parameters and in a certain range of wavenumbers $q$. However, generically, the spatially localized forcing and the non-thermal dynamics both introduce deviations from the thermal-like $q^{-2}$ spectrum.

  5. Mechanistic modelling of weak interlayers in flexible and semi-flexible road pavements: Part 2

    CSIR Research Space (South Africa)

    De Beer, Morris

    2012-04-01

    Full Text Available This paper (Part 2 of a two-part set of papers) discusses models and illustrates the adverse effects of weak layers, interlayers, laminations and/or weak interfaces in flexible and semi-flexible pavements, also incorporating lightly cemented layers...

  6. Miscibility of Semi-flexible Thermotropic Liquid Crystalline Copolyesteramide with Polyamide 66

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Liquid crystalline polymer-polyamide 66 (LCP/PA66) blends were compounded by usingaBrabender mixing followed by compression moulding. The LCP employed was a semi-flexible liquid crystalline copolyesteramide based on 30% (molar fraction) of p-amino benzoic acid (ABA)and 70% (molar fraction) of poly (ethylene terephthalate)(PET). The LCP/PA66 blends wereinvestigated in terms of the thermal and dynamic mechanical properties. It was found that PA66and LCP components of the blends are miscible in the molten state, but are partially miscible inthe solid state. The inclusion of the semi-flexible LCP into PA66 retards the crystallization rateof PA66. Furthermore, the melting temperature and the degree of crystallinity of PA66 are reduced considerably due to the LCP addition.

  7. A new bead-spring model for simulation of semi-flexible macromolecules

    Science.gov (United States)

    Saadat, Amir; Khomami, Bamin

    2016-11-01

    A bead-spring model for semi-flexible macromolecules is developed to overcome the deficiencies of the current coarse-grained bead-spring models. Specifically, model improvements are achieved through incorporation of a bending potential. The new model is designed to accurately describe the correlation along the backbone of the chain, segmental length, and force-extension behavior of the macromolecule even at the limit of 1 Kuhn step per spring. The relaxation time of different Rouse modes is used to demonstrate the capabilities of the new model in predicting chain dynamics.

  8. In vitro evaluation of a low-modulus mesh canine prosthetic hip stem.

    Science.gov (United States)

    Marcellin-Little, Denis J; Cansizoglu, Omer; Harrysson, Ola L A; Roe, Simon C

    2010-09-01

    To compare an electron beam melting-processed (EBMP) low-modulus titanium alloy mesh stem with a commercial cobalt-chromium (CC) stem in a canine cadaver model. 9 pairs of cadaver femora. EBMP stems of 3 sizes were placed in randomly chosen sides of femora (left or right) and CC stems in opposite sides. Stem impaction distances were recorded. Five strain gauges were attached to the femoral surface to record transverse tensile (hoop) strains in the femur during axial loading. Constructs were axially loaded 4 times to 800 N and 4 times to 1,600 N in a materials testing machine. Axial stiffness of constructs and bone surface strains were compared between EBMP and CC constructs. Stems were impacted without creating femoral fissures or fractures. Stem impaction distances were larger for EBMP stems than for CC stems. Mean axial stiffness of EBMP constructs was lower than mean axial stiffness of CC constructs. Subsidence did not differ between groups. Bone strains varied among strain gauge positions and were largest at the distal aspect of the stems. At a load of 1,600 N, bones strains were higher in CC constructs than in EBMP constructs for 2 of 4 medial strain gauges. EBMP stems were successfully impacted and stable and led to a focal decrease in bone strain; this may represent an acceptable option for conventional or custom joint replacement.

  9. Integration of colloids into a semi-flexible network of fibrin.

    Science.gov (United States)

    Bharadwaj, N Ashwin K; Kang, Jin Gu; Hatzell, Marta C; Schweizer, Kenneth S; Braun, Paul V; Ewoldt, Randy H

    2017-02-15

    Typical colloid-polymer composites have particle diameters much larger than the polymer mesh size, but successful integration of smaller colloids into a large-mesh network could allow for the realization of new colloidal states of spatial organization and faster colloid motion which can allow the possibility of switchable re-configuration of colloids or more dramatic stimuli-responsive property changes. Experimental realization of such composites requires solving non-trivial materials selection and fabrication challenges; key questions include composition regime maps of successful composites, the resulting structure and colloidal contact network, and the mechanical properties, in particular the ability to form a network and retain strain stiffening in the presence of colloids. Here, we study these fundamental questions by formulating composites with fluorescent (though not stimuli-responsive) carboxylate modified polystyrene/latex (CML) colloidal particles (diameters 200 nm and 1000 nm) in bovine fibrin networks (a semi-flexible biopolymer network with mesh size 1-5 μm). We describe and characterize two methods of composite preparation: adding colloids before fibrinogen polymerization (Method I), and electrophoretically driving colloids into a network already formed by fibrinogen polymerization (Method II). We directly image the morphology of colloidal and fibrous components with two-color fluorescent confocal microscopy under wet conditions and SEM of fixed dry samples. Mechanical properties are studied with shear and extensional rheology. Both fabrication methods are successful, though with trade-offs. Method I retains the nonlinear strain-stiffening and extensibility of the native fibrin network, but some colloid clustering is observed and fibrin network integrity is lost above a critical colloid concentration that depends on fibrinogen and thrombin concentration. Larger colloids can be included at higher volume fractions before massive aggregation occurs

  10. A fast platform for simulating semi-flexible fiber suspensions applied to cell mechanics

    Science.gov (United States)

    Nazockdast, Ehssan; Rahimian, Abtin; Zorin, Denis; Shelley, Michael

    2017-01-01

    semi-flexible fibers.

  11. A fast platform for simulating semi-flexible fiber suspensions applied to cell mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Nazockdast, Ehssan, E-mail: ehssan@cims.nyu.edu [Courant Institute of Mathematical Sciences, New York University, New York, NY 10012 (United States); Center for Computational Biology, Simons Foundation, New York, NY 10010 (United States); Rahimian, Abtin, E-mail: arahimian@acm.org [Courant Institute of Mathematical Sciences, New York University, New York, NY 10012 (United States); Zorin, Denis, E-mail: dzorin@cs.nyu.edu [Courant Institute of Mathematical Sciences, New York University, New York, NY 10012 (United States); Shelley, Michael, E-mail: shelley@cims.nyu.edu [Courant Institute of Mathematical Sciences, New York University, New York, NY 10012 (United States); Center for Computational Biology, Simons Foundation, New York, NY 10010 (United States)

    2017-01-15

    cloud of semi-flexible fibers.

  12. 半柔同轴电缆专用高速浸锡机研究%High-speed semi-flexible coaxial cable Soldering Machine Research

    Institute of Scientific and Technical Information of China (English)

    简裕利

    2014-01-01

    This paper introduces what is semi flexible coaxial cable,domestic production situation of semi flexible coaxial cable,tin dipping process focus on semi flexible coaxial cable is analyzed,and studied the design method of high speed tin dipping machine.%本文介绍了何为半柔同轴电缆,国内半柔同轴电缆的生产现状,重点对半柔同轴电缆的浸锡工艺进行了分析,并研究了高速浸锡机设计方法。

  13. Pavement structure mechanics response of flexible on semi-flexible overlay that based on the old cement concrete pavement damage

    Directory of Open Access Journals (Sweden)

    Jiang Ruinan

    2015-01-01

    Full Text Available The old cement pavement damage status directly affect the design of the paving renovation. Based on the state of the old road investigation, combined with the research data at home and abroad, use the control index that average deflection, deflection value and CBR value to determine the reasonable time to overlay. Draw up the typical pavement structure according to the principle of combination of old cement pavement overlay structure design, and calculated that the tensile stress and shear stress in asphalt layer ,semi-flexible layer and the tensile in the old cement pavement adopting BISA3.0 statics finite element analysis model when modulus in the old road was diminishing. Use the computed result to analyses the influence of old road damage condition the influence of pavement structure.

  14. Mechanical and microstructural characterization of new nickel-free low modulus β-type titanium wires during thermomechanical treatments

    Energy Technology Data Exchange (ETDEWEB)

    Guillem-Martí, J. [Biomaterials, Biomechanics and Tissue Engineering Group, Department of Materials Science and Metallurgy, Technical University of Catalonia (UPC), ETSEIB, Av. Diagonal 647, 08028 Barcelona (Spain); Biomedical Research Networking Centre in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Campus Río Ebro, Edificio I+D Bloque 5, 1a planta, C/ Poeta Mariano Esquillor s/n, 50018 Zaragoza (Spain); Centre for Research in NanoEngineering (CRNE) – UPC, C/Pascual i Vila 15, 08028 Barcelona (Spain); Herranz-Díez, C. [Biomaterials, Biomechanics and Tissue Engineering Group, Department of Materials Science and Metallurgy, Technical University of Catalonia (UPC), ETSEIB, Av. Diagonal 647, 08028 Barcelona (Spain); Biomedical Research Networking Centre in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Campus Río Ebro, Edificio I+D Bloque 5, 1a planta, C/ Poeta Mariano Esquillor s/n, 50018 Zaragoza (Spain); Shaffer, J.E. [Fort Wayne Metals Research Products Corporation, 9609 Ardmore Avenue, 46809 Fort Wayne (United States); Gil, F.J. [Biomaterials, Biomechanics and Tissue Engineering Group, Department of Materials Science and Metallurgy, Technical University of Catalonia (UPC), ETSEIB, Av. Diagonal 647, 08028 Barcelona (Spain); Biomedical Research Networking Centre in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Campus Río Ebro, Edificio I+D Bloque 5, 1a planta, C/ Poeta Mariano Esquillor s/n, 50018 Zaragoza (Spain); Centre for Research in NanoEngineering (CRNE) – UPC, C/Pascual i Vila 15, 08028 Barcelona (Spain); and others

    2015-06-11

    NiTi alloy is the only practical shape memory alloy (SMA) in biomedical use because of its excellent mechanical stability and functionality. However, it is estimated that between 4.5% and 28.5% of the population are hypersensitive to nickel metal, with a higher prevalence in females. Therefore, developing nickel-free low modulus β-type titanium alloys showing shape memory or super elastic behavior would have a great interest in the biomaterials field. Homogeneous 127 μm diameter Ti25Hf21Nb wires were produced and compared to straight annealed Ti–50.8 at% Ni (Nitinol) and 90% cold-drawn 316L wires. Microstructural changes taking place during the heat treatment of cold-worked Ti25Hf21Nb wires were investigated. Large plastic deformation during wire drawing and subsequent annealing led to nano-crystallization and amorphization which may contribute to the observed superelasticity. Mechanical properties were characterized using cyclic uniaxial tension and rotary beam fatigue test modes. A modulus of elasticity of less than 60 GPa and axial recoverable strain of greater than 3% were observed with stress hysteresis resembling a reversible stress-induced martensitic transformation at higher temperatures. The new Ti25Hf21Nb alloy is an important candidate for developing Ni-free SMAs in the future.

  15. How tension propagates for a driven semi-flexible chain while translocating through a nano-pore

    Science.gov (United States)

    Adhikari, Ramesh; Bhattacharya, Aniket

    2013-03-01

    Driven translocation of a stiff chain through a nano-pore is studied using Langevin dynamics in two dimension (2D). We observe that for a given chain length N the mean first passage time (MFPT) increases for a stiffer chain and the translocation exponent α ( ~Nα) satisfies the inequality 2 ν exponent for a given chain stiffness. We calculate the residence time of the individual monomers and observe that the peak position of the residence time W (m) as a function of the monomer index m shifts at a lower m-value with increasing chain stiffness κb. Finally, we provide qualitative physical explanation for dependence of various quantities on chain stiffness κb by using ideas from Sakaue's tension propagation(TP) theory [Phys. Rev. E 76, 021803 (2007)] and its recent implementation into a Brownian dynamics tension propagation (BDTP) scheme for a finite chain by Ikonen et al. [J. Chem. Phys. 137, 085101 (2012); Phys. Rev. E 85, 051803 (2012)]for a semi-flexible chain. Partially supported by UCF Office of Research and Commercialization & College of Science SEED grant.

  16. A combined stretching-tilting mechanism produces negative, zero and positive linear thermal expansion in a semi-flexible Cd(II)-MOF.

    Science.gov (United States)

    Lama, Prem; Das, Raj Kumar; Smith, Vincent J; Barbour, Leonard J

    2014-06-21

    A novel semi-flexible Cd(II)-MOF has been synthesized and characterized by variable temperature powder and single-crystal X-ray diffraction. The material displays an unusual combination of thermal expansion (TE) i.e. negative, zero and positive, which is an extremely rare finding, especially for metal-organic frameworks as a result of a combined stretching-tilting mechanism.

  17. Sustainable Non-Metallic Building Materials

    Directory of Open Access Journals (Sweden)

    Svetlana Tretsiakova-McNally

    2010-01-01

    Full Text Available Buildings are the largest energy consumers and greenhouse gases emitters, both in the developed and developing countries. In continental Europe, the energy use in buildings alone is responsible for up to 50% of carbon dioxide emission. Urgent changes are, therefore, required relating to energy saving, emissions control, production and application of materials, use of renewable resources, and to recycling and reuse of building materials. In addition, the development of new eco-friendly building materials and practices is of prime importance owing to the growing environmental concerns. This review reflects the key tendencies in the sector of sustainable building materials of a non-metallic nature that have occurred over the past decade or so.

  18. A semi-flexible model prediction for the polymerization force exerted by a living F-actin filament on a fixed wall

    CERN Document Server

    Pierleoni, Carlo; Ryckaert, Jean-Paul

    2015-01-01

    We consider a single living semi-flexible filament with persistence length l_p in chemical equilibrium with an ideal solution of free monomers at fixed monomer chemical potential mu_1 and fixed temperature T. While one end of the filament is chemically active with single monomer (de)polymerization steps, the other end is grafted normally to a rigid wall to mimick a rigid network from which the filament under consideration emerges. A second rigid wall, parallel to the grafting wall, is fixed at distance L<semi-flexible, living, discrete Wormlike chain (d-WLC) model with step size d and...

  19. Vibration in metal and non-metal incubators.

    Science.gov (United States)

    Youngblut, J M; Lewandowski, W; Casper, G R; Youngblut, W R

    1994-01-01

    The purpose of this study was to determine the amount of vibration transmitted to the surface of an incubator mattress. Empty incubators with metal (n = 12) and non-metal (n = 12) bases were monitored for vibration levels when the incubators were turned "off" and when they were turned "on." High levels of low-frequency vibration were detected in both types of incubators in both conditions. The metal incubators transmitted significantly less vibration to the mattress than did the non-metal incubators at several frequencies in the "off," the "on," and the "adjusted" conditions. These results suggest that infants experience significant whole-body vibration while lying in incubators.

  20. Non-metallic inclusions in high manganese austenitic alloys

    OpenAIRE

    A. Grajcar; L. Bulkowski; U. Galisz

    2011-01-01

    Purpose: The aim of the paper is to identify the type, fraction and chemical composition of non-metallic inclusions modified by rare-earth elements in an advanced group of high-manganese austenitic C-Mn-Si-Al-type steels with Nb and Ti microadditions.Design/methodology/approach: The heats of 3 high-Mn steels of a various content of Si, Al and Ti were melted in a vacuum induction furnace and a modification of non-metallic inclusions was carried out by the mischmetal in the amount of 0.87 g or ...

  1. Interaction mechanism of non-metallic particles with crystallization front

    Directory of Open Access Journals (Sweden)

    Żak P. L.

    2017-03-01

    Full Text Available The process of steel solidification in the CCS mould is accompanied by a number of phenomena relating to the formation of non-metallic phase, as well as the mechanism of its interaction with the existing precipitations and the advancing crystallization front. In the solidification process the non-metallic inclusions may be absorbed or repelled by the moving front. As a result a specific distribution of non-metallic inclusions is obtained in the solidified ingot, and their distribution is a consequence of these processes. The interaction of a non-metallic inclusion with the solidification front was analyzed for alumina, for different values of the particle radius. The simulation was performed with the use of own computer program. Each time a balance of forces acting on a particle in its specific position was calculated. On this basis the change of position of alumina particle in relation to the front was defined for a specific radius and original location of the particle with respect to the front.

  2. A study on non-metallic structure of heliostat

    Energy Technology Data Exchange (ETDEWEB)

    Liu Xiaobin; Zang Chuncheng; Zhang Xiliang; Wang Yangzhong; Du Fengli [Himin Solar Energy Group Co., Ltd, Dezhou City (China); Wang Zhifeng [Inst. of Electrical Engineering, CAS, BJ (China)

    2008-07-01

    Heliostat constitutes a very important component in the solar power tower system. Its importance derives from three aspects: one is the large proportion in the total cost, accounting for about 50% of the whole, the other is its concentration efficiency and reflectivity heavily determining the power conversion from solar thermal energy to electrical energy, another is itself power consumption amount highly expressing failure or success of the power plant. Therefore, serious efforts and considerations from the structure, motion and control mode to material selection have to be given in the design and optimization of heliostat. In the present paper, the mechanical and aging performance of non-metallic materials is investigated and compared. The possibility of these non-metallic materials in the application of heliostat structure is discussed. (orig.)

  3. Non-metallic Inclusions in Continuously Cast Aluminum Killed Steels

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In aluminum killed steels, the size, shape, quantity and formation of non-metallic inclusions in ladle steel (before and after RH vacuum treatment) and in tundish as well as in slabs were studied by EPMA (Electron Probe Microanalysis) and by analyzing the total oxygen. The results showed that in the slabs the total oxygen was quite low and the inclusions discovered were mainly small-sized angular alumina inclusions. This indicates that most inclusions have been removed by floating out during the continuous casting process. In addition, the countermeasures were discussed to decrease the alumina inclusions in the slabs further.

  4. Testing theOdour Quality of Non-Metallic Materials

    Directory of Open Access Journals (Sweden)

    AVIJIT SINGH GANGWAR

    2014-10-01

    Full Text Available This report has been compiled on the completion of 3 week summer training at ICAT. It discusses about a very necessary and least popular part of the Automotive Industry i.e. Testing and Certification. It discusses about one of the government notified Testing body ICAT which is one of just 6 such organisations in India.This report deals with the odour quality testing of non-metallic materials that are used for automobile compartment and parts associated with the compartment.

  5. Shaking table experiment of semi-flexible suspended-floor structures%半柔性悬挂减振结构振动台试验研究

    Institute of Scientific and Technical Information of China (English)

    王春林; 吕志涛

    2012-01-01

    通过对设置黏滞流体阻尼器的半柔性悬挂结构进行地震模拟振动台试验,分析了主结构与悬挂楼面的质量比、连接方式、阻尼器的分布和层间斜撑对悬挂结构动力特性和响应的影响。试验结果表明:采用阻尼器连接主结构和悬挂楼面,可改变结构频率和振型阻尼比;当悬挂楼层侧向刚度较小时,结构振型表现为柔性层与悬挂楼面的耦合剪切变形;当增设斜撑后,结构第一振型为柔性层的层间变形;阻尼器连接时模型的主结构地震响应小于刚性连接的普通悬挂结构,通过增设斜撑可进一步提高减振效果;与自由悬挂结构相比,采用阻尼器连接的悬挂减振结构能够较好地抑制悬挂楼面相对于主结构的位移和悬挂楼面的层间位移;设置斜撑后,能够进一步减小悬挂楼面的层间位移,同时弱化了阻尼器不均匀对减振效果的影响。%A Shaking table experiment of a semi-flexible suspended-floor structure(SFSS) equipped with fluid viscous dampers had been conducted.The effects of link types and mass ratios between the primary structure and suspended floors,distribution patterns of dampers and diagonal braces on the dynamic characteristics and responses of suspended-floor structures were verified.Test results showed that the frequencies and mode damping ratios of the SFSS installed with dampers were adjusted and its first three modes were mainly governed by the coupling shear drift of suspended floors and the flexible layer when the shear stiffness of suspended floors was relatively small.After diagonal braces were installed,the first mode was governed by the story drift of the flexible layer.The maximum top floor displacement of the SFSS with dampers was smaller than traditional suspended-floor structure and installing diagonal braces can improve the vibration-controlling effect.Moreover,the SFSS with the dampers can effectively decrease the displacements of suspended floors

  6. Interaction of silicene and germanene with non-metallic substrates

    Science.gov (United States)

    Houssa, M.; Scalise, E.; van den Broek, B.; Lu, A.; Pourtois, G.; Afanas'ev, V. V.; Stesmans, A.

    2015-01-01

    By using first-principles simulations, we investigate the interaction of silicene and germanene with various non-metallic substrates. We first consider weak van der Waals interactions between the 2D layers and dichalcogenide substrates, like MoX2 (X=S, Se, Te). The buckling of the silicene or germanene layer is correlated to the lattice mismatch between the 2D material and the MoX2 template. The electronic properties of silicene or germanene on these different templates then largely depend on the buckling of the 2D material layer: highly buckled silicene or germanene on MoS2 are predicted to be metallic, while low buckled silicene on MoTe2 is predicted to be semi-metallic, with preserved Dirac cones at the K points. We next study the covalent bonding of silicene and germanene on (0001) ZnS and ZnSe surfaces. On these substrates, silicene or germanene are found to be semiconducting. Remarkably, the nature and magnitude of their energy band gap can be controlled by an out-of-plane electric field.

  7. A RISK MANAGEMENT METHODOLOGY FOR NON-METALLIC PROCESS EQUIPMENT

    Directory of Open Access Journals (Sweden)

    J.J. Viviers

    2012-01-01

    Full Text Available

    ENGLISH ABSTRACT: Many companies in South Africa have implemented the risk-based inspection (RBI methodology as a maintenance strategy. The risk involved in operating a piece of equipment, past history, non-destructive examination techniques, failure modes, and many other aspects determine the frequency of inspections required to meet legislation. The main purpose of the RBI methodology is to prevent failures of process equipment. The methodology for risk-based inspection for metal equipment is well-established and has been proven in industry, becoming the norm nationally and internationally. However, it is not possible to apply all the techniques to nonmetallic equipment owing to vast differences between the two types of materials. This paper discusses the results of data gathered on the RBI methodology for nonmetallic equipment, and proposes a risk-based model that can be used to perform a risk assessment for non-metallic equipment in a process plant. The risk assessment can be used to formulate the next inspection interval for the asset.

    AFRIKAANSE OPSOMMING: Verskeie maatskappye in Suid-Afrika het reeds die metodologie van risikogebaseeerde inspeksie (RBI geïmplementeer as deel van ‘n omvattende instandhoudingstrategie. Die risiko betrokke by ‘n fisiese item, bedryfsgeskiedenis, nie-vernietigende toetstegnieke, falingsmodusse, en vele ander aspekte bepaal die frekwensie van inspeksies wat benodig word om aan wetlike vereistes te voldoen. Die hoofdoel van die risiko-gebaseerde metodologie is om faling van prosestoerusting te verhinder. Die metodologie vir risiko-gebaseerde inspeksie van metaaltoerusting is goed bekend en word suksesvol toegepas in die industrie. Dis is egter nie moontlik om al die tegnieke toe te pas op nie-metaaltoerusting nie weens die groot verskeidenheid van materiaaltipes. Hierdie artikel bespreek die data wat ingewin is op die risiko-gebaseerde metodologie vir nie-metaaltipeprosestoerusting, en stel

  8. 拉萨地区不同空隙率的半柔性路面材料冻融试验研究%Freezing-Thawing Test Research of Semi-Flexible Pavement Materials with Different Void Fraction in Lhasa

    Institute of Scientific and Technical Information of China (English)

    李成洋; 张鹏; 王文奇; 田荣燕

    2016-01-01

    为解决现有水泥混凝土和沥青混凝土路面材料在拉萨地区推广应用中受冻融作用破坏的问题,对不同空隙率的半柔性路面材料在拉萨的应用进行研究。采用灌注式的方式将水泥胶浆灌入不同空隙率的开级配沥青混合料母体中制成试件,并根据拉萨独特的气候特征设定冻融试验的时间和温度;再进行高温稳定试验和低温抗裂试验,得出趋近于真实冻融环境的试验数据。分析试验数据可得,半柔性路面材料在受到冻融作用破坏时,低温抗裂强度随着空隙率的增大呈逐渐上升趋势,劈裂位移量随着空隙率的增大呈逐渐减小趋势;而表征高温稳定性能的动稳定度随着空隙率的增大呈先上升后下降的趋势,变形速率随着空隙率的增大呈先下降后上升的趋势。研究结果表明,半柔性路面材料采用27%的空隙率并添加塑弹性材料有利于抵抗冻融破坏,从而能够在高原地区推广和应用。%In order to solve the problem that the cement concrete and asphalt concrete pavement materi⁃al were damaged by freezing-thawing action during their popularization and application in Lhasa, a re⁃search about the application of semi-flexible pavement materials with different void fraction in Lhasa was carried out. Test specimens were made by the way of pouring cement mortar into open-graded as⁃phalt mixture matrix with different void fraction. The time and temperature of freezing-thawing test were set based on the special environment of Lhasa. Then the high-temperature stability test and low-temper⁃ature crack resistance test were carried out to obtain the test data closing to the real environment. By ana⁃lyzing the test data, it was educed that:when semi-flexible pavement material was destroyed by freezing-thawing action, with the increasing of void fraction, the low-temperature crack resistance increased grad⁃ually, and the split displacement

  9. Size of Non-Metallic Inclusions in High-Grade Medium Carbon Steel

    OpenAIRE

    Lipiński T.; Wach A.

    2014-01-01

    Non-metallic inclusions found in steel can affect its performance characteristics. Their impact depends not only on their quality, but also, among others, on their size and distribution in the steel volume. The literature mainly describes the results of tests on hard steels, particularly bearing steels. The amount of non-metallic inclusions found in steel with a medium carbon content melted under industrial conditions is rarely presented in the literature. The tested steel was melted in an el...

  10. The Effect of Different Non-Metallic Inclusions on the Machinability of Steel

    OpenAIRE

    Niclas Ånmark; Andrey Karasev; Pär Göran Jönsson

    2015-01-01

    Considerable research has been conducted over recent decades on the role of non-metallic inclusions and their link to the machinability of different steels. The present work reviews the mechanisms of steel fractures during different mechanical machining operations and the behavior of various non-metallic inclusions in a cutting zone. More specifically, the effects of composition, size, number and morphology of inclusions on machinability factors (such as cutting tool wear, power consumption, ...

  11. Modification of Non-Metallic Inclusions by Rare-Earth Elements in Microalloyed Steels

    Directory of Open Access Journals (Sweden)

    M. Opiela

    2012-04-01

    Full Text Available The modification of the chemical composition of non-metallic inclusions by rare-earth elements in the new-developed microalloyed steels was discussed in the paper. The investigated steels are assigned to production of forged elements by thermo- mechanical treatment. The steels were melted in a vaccum induction furnace and modification of non-metallic inclusions was carried out by the michmetal in the amount of 2.0 g per 1 kg of steel. It was found that using material charge of high purity and a realization of metallurgical process in vacuous conditions result in a low concentration of sulfur (0.004%, phosphorus (from 0.006 to 0.008% and oxygen (6 ppm. The high metallurgical purity is confirmed by a small fraction of non-metallic inclusions averaging 0.075%. A large majority of non-metallic inclusions are fine, globular oxide-sulfide or sulfide particles with a mean size 17m2. The chemical composition and morphology of non-metallic inclusions was modified by Ce, La and Nd, what results a small deformability of non- metallic inclusions during hot-working.

  12. 半柔性路面大空隙基体沥青混合料设计与性能研究%Study on the Design and Performance of Large Void Basic Asphalt Mixture for Semi-flexible Pavement

    Institute of Scientific and Technical Information of China (English)

    王凤华; 王伟明; 吴旷怀

    2015-01-01

    In this paper,three kinds of large void basic asphalt mixture with different voidages for semi-flexible pavement are designed based on the coarse aggregate voids-filling method (CAVF).The Marshall Test,permeability test,determination of voidage and other performance tests are presented.The results show that the designed voidge and measured voidge are close in the three kinds of basic-asphalt-mixture with different viodages designed by CAVF,and have the appropriate strength,good drainage per-formance,the mortar can be poured strong.%基于矿料主骨料空隙体积填充法(CAVF)设计了3种不同空隙率的半柔性路面大空隙基体沥青混合料,采用马歇尔试验、透水试验与空隙率测定等试验评价其性能。结果表明,采用 CAVF 法设计的3种不同空隙率的基体沥青混合料,设计空隙率与实测空隙率较为接近,且具有适当的强度,较好的排水性能,砂浆的可灌入性强。

  13. Synthesis and Catalytic Applications of Non-Metal Doped Mesoporous Titania

    Directory of Open Access Journals (Sweden)

    Syed Z. Islam

    2017-03-01

    Full Text Available Mesoporous titania (mp-TiO2 has drawn tremendous attention for a diverse set of applications due to its high surface area, interfacial structure, and tunable combination of pore size, pore orientation, wall thickness, and pore connectivity. Its pore structure facilitates rapid diffusion of reactants and charge carriers to the photocatalytically active interface of TiO2. However, because the large band gap of TiO2 limits its ability to utilize visible light, non-metal doping has been extensively studied to tune the energy levels of TiO2. While first-principles calculations support the efficacy of this approach, it is challenging to efficiently introduce active non-metal dopants into the lattice of TiO2. This review surveys recent advances in the preparation of mp-TiO2 and their doping with non-metal atoms. Different doping strategies and dopant sources are discussed. Further, co-doping with combinations of non-metal dopants are discussed as strategies to reduce the band gap, improve photogenerated charge separation, and enhance visible light absorption. The improvements resulting from each doping strategy are discussed in light of potential changes in mesoporous architecture, dopant composition and chemical state, extent of band gap reduction, and improvement in photocatalytic activities. Finally, potential applications of non-metal-doped mp-TiO2 are explored in water splitting, CO2 reduction, and environmental remediation with visible light.

  14. Fabrication of Biomedical Titanium Alloys with High Strength and Low Modulus by Means of Powder Metallurgy%粉末冶金法合成高强低模超细晶医用钛合金

    Institute of Scientific and Technical Information of China (English)

    李元元; 邹黎明; 杨超

    2012-01-01

    为探寻有效的高强低模医用钛合金制备方法,采用机械合金化方法制备了不同Fe含量的(Ti69.7Nb23.7Zr4.9Ta1.7)100-xFex非晶/纳米晶合金粉末,随后采用放电等离子烧结-非晶晶化法得到了高强低模的超细晶钛基复合材料.结果表明:(1)机械合金化过程中,Fe含量对合金的非晶形成能力影响显著,文中实验条件下,只有当x增大至10时才能形成全非晶相的非晶粉末;(2)Fe含量也明显影响合成的块体钛合金的力学性能,合成的不同Fe含量合金中,只有(Ti69.7Nb23.7Zr4.9Ta1.7)94 Fe6合金具有高强度和显著塑性,其压缩屈服强度为2425 MPa,断裂强度为2650 MPa,断裂应变为0.0691,平均弹性模量仅为52 GPa,接近第三代生物医用钛合金的最低值.将所合成的超细晶钛合金与常用的两种生物钛合金(Ti-6Al-4V和Ti-13Nb-13Zr)进行抗摩擦磨损性能对比,发现所合成的钛合金具有最佳的耐磨性.%In order to explore an effective method to fabricate biomedical Ti alloy with high strength and low modulus, amorphous/nanocrystallized (Ti69.7Nb23.7Zr4.9Ta1.7) 100_x.Fe;c alloy powders with different Fe contents were synthesized via mechanical alloying, and, subsequently, ultrafine-grained Ti-based composites with high strength and low modulus were fabricated via the spark plasma sintering-amorphous crystallization. The results show that, during the performed mechanical alloying, Fe content significantly affects the glass-forming ability of the alloy system, concretely, fully amorphous structure forms only when x reaches 10; and that Fe content also has an obvious effect on the mechanical properties of the bulk composites, only the bulk composite at a x value of 6 possesses high strength and distinct plasticity, with the corresponding compressive yield stress, fracture stress and fracture strain respectively being 2425 MPa, 2650 MPa and 0. 069 1, and with an average elastic modulus of 52 GPa that is close to the minimum

  15. Fatigue Strength Prediction of Drilling Materials Based on the Maximum Non-metallic Inclusion Size

    Science.gov (United States)

    Zeng, Dezhi; Tian, Gang; Liu, Fei; Shi, Taihe; Zhang, Zhi; Hu, Junying; Liu, Wanying; Ouyang, Zhiying

    2015-12-01

    In this paper, the statistics of the size distribution of non-metallic inclusions in five drilling materials were performed. Based on the maximum non-metallic inclusion size, the fatigue strength of the drilling material was predicted. The sizes of non-metallic inclusions in drilling materials were observed to follow the inclusion size distribution rule. Then the maximum inclusion size in the fatigue specimens was deduced. According to the prediction equation of the maximum inclusion size and fatigue strength proposed by Murakami, fatigue strength of drilling materials was obtained. Moreover, fatigue strength was also measured through rotating bending tests. The predicted fatigue strength was significantly lower than the measured one. Therefore, according to the comparison results, the coefficients in the prediction equation were revised. The revised equation allowed the satisfactory prediction results of fatigue strength of drilling materials at the fatigue life of 107 rotations and could be used in the fast prediction of fatigue strength of drilling materials.

  16. Modelling of non-metallic particles motion process in foundry alloys

    Directory of Open Access Journals (Sweden)

    P. L. Żak

    2015-04-01

    Full Text Available The behaviour of non-metallic particles in the selected composites was analysed, in the current study. The calculations of particles floating in liquids differing in viscosity were performed. Simulations based on the Stokes equation were made for spherical SiC particles and additionally the particle size influence on Reynolds number was analysed.The movement of the particles in the liquid metal matrix is strictly connected with the agglomerate formation problem.Some of collisions between non-metallic particles lead to a permanent connection between them. Creation of the two spherical particles and a metallic phase system generates the adhesion force. It was found that the adhesion force mainly depends on the surface tension of the liquid alloy and radius of non-metallic particles.

  17. The Effect of Different Non-Metallic Inclusions on the Machinability of Steels.

    Science.gov (United States)

    Ånmark, Niclas; Karasev, Andrey; Jönsson, Pär Göran

    2015-02-16

    Considerable research has been conducted over recent decades on the role of non‑metallic inclusions and their link to the machinability of different steels. The present work reviews the mechanisms of steel fractures during different mechanical machining operations and the behavior of various non-metallic inclusions in a cutting zone. More specifically, the effects of composition, size, number and morphology of inclusions on machinability factors (such as cutting tool wear, power consumption, etc.) are discussed and summarized. Finally, some methods for modification of non-metallic inclusions in the liquid steel are considered to obtain a desired balance between mechanical properties and machinability of various steel grades.

  18. Modification of Non-Metallic Inclusions by Rare-Earth Elements in Microalloyed Steels

    OpenAIRE

    Opiela M.; Grajcar A.

    2012-01-01

    The modification of the chemical composition of non-metallic inclusions by rare-earth elements in the new-developed microalloyed steels was discussed in the paper. The investigated steels are assigned to production of forged elements by thermo- mechanical treatment. The steels were melted in a vaccum induction furnace and modification of non-metallic inclusions was carried out by the michmetal in the amount of 2.0 g per 1 kg of steel. It was found that using material charge of high purity and...

  19. The Effect of Different Non-Metallic Inclusions on the Machinability of Steels

    Directory of Open Access Journals (Sweden)

    Niclas Ånmark

    2015-02-01

    Full Text Available Considerable research has been conducted over recent decades on the role of non‑metallic inclusions and their link to the machinability of different steels. The present work reviews the mechanisms of steel fractures during different mechanical machining operations and the behavior of various non-metallic inclusions in a cutting zone. More specifically, the effects of composition, size, number and morphology of inclusions on machinability factors (such as cutting tool wear, power consumption, etc. are discussed and summarized. Finally, some methods for modification of non-metallic inclusions in the liquid steel are considered to obtain a desired balance between mechanical properties and machinability of various steel grades.

  20. Stepped-Frequency Ground-Penetrating Radar for Detection of Small Non-metallic Buried Objects

    DEFF Research Database (Denmark)

    Jakobsen, Kaj Bjarne; Sørensen, Helge Bjarup Dissing; Nymann, Ole

    1997-01-01

    A monostatic amplitude and phase stepped-frequency radar approach have been proposed to detect small non-metallic buried anti-personnel (AP) mines. An M-56 AP-mine with a diameter of 54 mm and height of 40 mm, only, has been successfully detected and located in addition to small metallic mine...

  1. Soil effects on GPR detection of buried non-metallic mines

    NARCIS (Netherlands)

    Hendrickx, J.M.H.; Hong, S.H.; Miller, T.; Borchers, B.; Rhebergen, J.B.

    2003-01-01

    Landmines are a major problem in many areas of the world. In spite of the fact that many different types of landmine sensors have been developed, the detection of non-metallic landmines remains very difficult. The objective of this contribution is to synthesize our work related to the effects of soi

  2. The Measurement of Hardness and Elastic Modulus of non-Metallic Inclusions in Steely Welding Joints

    Directory of Open Access Journals (Sweden)

    Ignatova Anna

    2015-08-01

    Full Text Available Trunk pipelines work under a cyclic dynamical mechanical load because when oil or gas is pumped, the pressure constantly changes - pulsates. Therefore, the fatigue phenomenon is a common reason of accidents. The fatigue phenomenon more often happens in the zone of non-metallic inclusions concentration. To know how the characteristics of nonmetallic inclusions influence the probability of an accident the most modern research methods should be used. It is determined with the help of the modern research methods that the accident rate of welded joints of pipelines is mostly influenced by their morphological type, composition and size of nonmetallic inclusions, this effect is more important than the common level of pollution by non-metallic inclusions. The article presents the results of the investigations of welded joints, obtained after the use of different common welding materials. We used the methods, described in the state standards: scanning electronic microscopy, spectral microprobe analysis and nano-indentation. We found out that non-metallic inclusions act like stress concentrators because they shrink, forming a blank space between metal and nonmetallic inclusions; it strengthens the differential properties on this boundary. Nonmetallic inclusion is not fixed, it can move. The data that we have received mean that during welded joints’ contamination (with non-metallic inclusions monitoring process, more attention should be paid to the content of definite inclusions, but not to total contamination.

  3. Size of Non-Metallic Inclusions in High-Grade Medium Carbon Steel

    Directory of Open Access Journals (Sweden)

    Lipiński T.

    2014-12-01

    Full Text Available Non-metallic inclusions found in steel can affect its performance characteristics. Their impact depends not only on their quality, but also, among others, on their size and distribution in the steel volume. The literature mainly describes the results of tests on hard steels, particularly bearing steels. The amount of non-metallic inclusions found in steel with a medium carbon content melted under industrial conditions is rarely presented in the literature. The tested steel was melted in an electric arc furnace and then desulfurized and argonrefined. Seven typical industrial melts were analyzed, in which ca. 75% secondary raw materials were used. The amount of non-metallic inclusions was determined by optical and extraction methods. The test results are presented using stereometric indices. Inclusions are characterized by measuring ranges. The chemical composition of steel and contents of inclusions in every melts are presented. The results are shown in graphical form. The presented analysis of the tests results on the amount and size of non-metallic inclusions can be used to assess them operational strength and durability of steel melted and refined in the desulfurization and argon refining processes.

  4. The mineral base and productive capacities of metals and non-metals of Kosovo

    Energy Technology Data Exchange (ETDEWEB)

    Rizaj, M.; Beqiri, E.; McBow, I.; O' Brien, E.Z.; Kongoli, F. [University of Prishtina, Prishtina (Kosovo)

    2008-08-15

    All historical periods of Kosovo - Ilirik, Roman, Medieval, Turkish, and former Yugoslavian - are linked with the intensive development of mining and metallurgy. This activity influenced and still is influencing the overall position of Kosovo as a country. For example, according to a 2006 World Bank report as well as other studies, Kosovo has potential lignite resources (geological reserves) of about 1.5 billion tonnes, which are ranked fifth in the world in importance. Other significant Kosovan mineral resources include lead, zinc, gold, silver, bauxite, and uranium, and rare metals accompanying those minerals, including indium, cadmium, thallium, gallium, and bismuth. These rare metals are of particular importance in developing advanced industrial technologies. Kosovo also has reserves of high-quality non-metals, including magnesite, quartz grit, bentonite, argil, talc, and asbestos. No database exists for these non-metal reserves, and further research and studies are needed.

  5. The mineral base and productive capacities of metals and non-metals of Kosovo

    Science.gov (United States)

    Rizaj, M.; Beqiri, E.; McBow, I.; O'Brien, E. Z.; Kongoli, F.

    2008-08-01

    All historical periods of Kosovo—Ilirik, Roman, Medieval, Turkish, and former Yugoslavian—are linked with the intensive development of mining and metallurgy. This activity influenced and still is influencing the overall position of Kosovo as a country. For example, according to a 2006 World Bank report as well as other studies, Kosovo has potential lignite resources (geological reserves) of about 1.5 billion tonnes, which are ranked fifth in the world in importance. Other significant Kosovan mineral resources include lead, zinc, gold, silver, bauxite, and uranium, and rare metals accompanying those minerals, including indium, cadmium, thallium, gallium, and bismuth. These rare metals are of particular importance in developing advanced industrial technologies. Kosovo also has reserves of high-quality non-metals, including magnesite, quartz grit, bentonite, argil, talc, and asbestos. No database exists for these non-metal reserves, and further research and studies are needed.

  6. Computer Simulation of the Formation of Non-Metallic Precipitates During a Continuous Casting of Steel

    Directory of Open Access Journals (Sweden)

    Kalisz D.

    2016-03-01

    Full Text Available The authors own computer software, based on the Ueshima mathematical model with taking into account the back diffusion, determined from the Wołczyński equation, was developed for simulation calculations. The applied calculation procedure allowed to determine the chemical composition of the non-metallic phase in steel deoxidised by means of Mn, Si and Al, at the given cooling rate. The calculation results were confirmed by the analysis of samples taken from the determined areas of the cast ingot. This indicates that the developed computer software can be applied for designing the steel casting process of the strictly determined chemical composition and for obtaining the required non-metallic precipitates.

  7. Non-metallic catalysts for diamond synthesis under high pressure and high temperature

    Institute of Scientific and Technical Information of China (English)

    孙力玲; 吴奇; 戴道扬; 张君; 秦志成; 王文魁

    1999-01-01

    Recent results on conversion from graphite to diamond by aid of non-metallic catalysts are reviewed. The current status of experimental advances is presented and typical examples from relevant literature are provided for understanding the mechanism of the graphite-diamond conversion by aid of these non-metallic catalysts. Furthermore, a tendency of graphite-diamond transformation assisted by carbonates, sulfates or phosphorus under high pressure and high temperature has been investigated by calculating the activation energy and transformation probability of the carbon atoms over a potential barrier. It was found that the activation energy is highly sensitive to the catalyst chosen. The probability sequence of graphite-diamond transformation with these catalysts was put forward.

  8. Motion behavior of non-metallic particles under high frequency magnetic field

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhong-tao; GUO Qing-tao; YU Feng-yun; LI Jie; ZHANG Jian; LI Ting-ju

    2009-01-01

    Non-metallic particles, especially alumina, are the main inclusions in aluminum and its alloys. Numerical simulation and the corresponding experiments were carried out to study the motion behavior of alumina particles in commercial pure aluminum under high frequency magnetic field. At the meantime, multi-pipe experiment was also done to discuss the prospect of continuous elimination of non-metallic particles under high frequency magnetic field. It is shown that: 1) results of numerical simulation are in good agreement with the experimental results, which certificates the rationality of the simulation model; 2) when the intensity of high frequency magnetic field is 0.06 T, the 30 μm alumina particles in melt inner could migrate to the edge and be removed within 2 s; 3) multi-pipe elimination of alumina particles under high frequency magnetic field is also effective and has a good prospect in industrial application.

  9. Color stability, water sorption and cytotoxicity of thermoplastic acrylic resin for non metal clasp denture

    OpenAIRE

    Jang, Dae-Eun; Lee, Ji-Young; Jang, Hyun-Seon; Lee, Jang-Jae; Son, Mee-Kyoung

    2015-01-01

    PURPOSE The aim of this study was to compare the color stability, water sorption and cytotoxicity of thermoplastic acrylic resin for the non-metal clasp dentures to those of thermoplastic polyamide and conventional heat-polymerized denture base resins. MATERIALS AND METHODS Three types of denture base resin, which are conventional heat-polymerized acrylic resin (Paladent 20), thermoplastic polyamide resin (Bio Tone), thermoplastic acrylic resin (Acrytone) were used as materials for this study...

  10. NON-METALLIC IMPURITIES AND FORMING OF THE STRUCTURE OF THE MODIFIED HIGH-MANGANESE STEEL

    Directory of Open Access Journals (Sweden)

    A. I. Garost

    2006-01-01

    Full Text Available The composition and morphology of chemical associations (non-metallic impurities and other ‘‘secondary” phases at modification of high-manganese steel by nitrogen and nitrideforming elements (vanadium are investigated. The optimal compositions of steel for production of castings are offered. The technology of the steel wear-resistance modification by vanadium of waste of industrial enterprises is worked out.

  11. Behavior of Non-metallic Inclusions in Centrifugal Induction Electroslag Castings

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    (para)In order to know the behavior of non-metallic inclusions in centrifugal induction electroslag castings (CIESC), non-metallic inclusions in 5CrMnMo and 4Cr5MoSiV1 were qualitatively and quantitatively analyzed. The largest size of inclusions in the casting and the thermodynamic possibility of TiN precipitation in steel were also calculated. The results show that sulfide inclusions are evenly distributed and the content is low. The amount of oxide inclusions in CIESC 4Cr5MoSiV1 steel is close to the ESR steel and lower than that in the EAF steel, and there are some differences along radial direction. Nitride inclusions are fine and the diameter of the largest one is 3~4um. With the increase of the centrifugal machine's rotational speed, the ratio of round inclusions increases and the ratio of sharp inclusions decreases. According to the experiment and the calculation results, it is pointed out that the largest diameter of non-metallic inclusions in the CIESC 4Cr5MoSiV1 casting is only 6.6mu, and [N%][Ti%] in 4Cr5MoSiV1 steel should be controlled less than 4.4~#U00d7tex010^{-5} in order to further reduce the amount and size of TiN inclusions.

  12. Evaluation of Characteristics of Non-Metallic Inclusions in P/M Ni-Base Superalloy by Automatic Image Analysis

    Institute of Scientific and Technical Information of China (English)

    Li; Xinggang; Ge; Changchun; Shen; Weiping

    2007-01-01

    Non-metallic inclusions,especially the large ones,within P/M Ni-base superalloy have a major influence on fatigue characteristics,but are not directly measurable by routine inspection.In this paper,a method,automatic image analysis,is proposed for estimation of the content,size and amount of non-metallic inclusions in superalloy.The methodology for the practical application of this method is described and the factors affecting the precision of the estimation are discussed.In the experiment,the characteristics of the non-metallic inclusions in Ni-base P/M superalloy are analyzed.

  13. Non-metallic, non-Fermi-liquid resistivity of FeCrAs from 0 to 17 GPa.

    Science.gov (United States)

    Tafti, F F; Wu, W; Julian, S R

    2013-09-25

    An unusual, non-metallic resistivity of the 111 iron-pnictide compound FeCrAs is shown to be relatively unchanged under pressures of up to 17 GPa. Combined with our previous finding that this non-metallic behaviour persists from at least 80 mK to 800 K, this shows that the non-metallic phase is exceptionally robust. Antiferromagnetic order, with a Néel temperature TN ∼ 125 K at ambient pressure, is suppressed by pressure at a rate of 7.0 ± 0.4 K GPa(-1), falling to ∼50 K at 10 GPa. We conclude that the formation of a spin-density-wave gap at TN does not play an important role in the non-metallic resistivity of FeCrAs at low temperatures.

  14. Non-metallic inclusions structure dimension in high quality steel with medium carbon contents

    Directory of Open Access Journals (Sweden)

    T. Lipiński

    2009-07-01

    Full Text Available The experimental material consisted of semi-finished products of high-grade, medium-carbon structural steel. The production process involved two melting technologies: steel melting in a 140-ton basic arc furnace with desulfurization and argon refining variants, and in a 100-ton oxygen converter. Billet samples were collected to analyze the content of non-metallic inclusions with the use of an optical microscope and a video inspection microscope. The results were processed and presented in graphic form.

  15. The Effect of Fine Non-Metallic Inclusions on the Fatigue Strength of Structural Steel

    Directory of Open Access Journals (Sweden)

    Lipiński T.

    2015-04-01

    Full Text Available The article discusses the results of a study investigating the effect of the number of fine non-metallic inclusions (up to 2 µm in size on the fatigue strength of structural steel during rotary bending. The study was performed on 21 heats produced in an industrial plant. Fourteen heats were produced in 140 ton electric furnaces, and 7 heats were performed in a 100 ton oxygen converter. All heats were desulfurized. Seven heats from electrical furnaces were refined with argon, and heats from the converter were subjected to vacuum circulation degassing.

  16. Separation of the metallic and non-metallic fraction from printed circuit boards employing green technology.

    Science.gov (United States)

    Estrada-Ruiz, R H; Flores-Campos, R; Gámez-Altamirano, H A; Velarde-Sánchez, E J

    2016-07-05

    The generation of electrical and electronic waste is increasing day by day; recycling is attractive because of the metallic fraction containing these. Nevertheless, conventional techniques are highly polluting. The comminution of the printed circuit boards followed by an inverse flotation process is a clean technique that allows one to separate the metallic fraction from the non-metallic fraction. It was found that particle size and superficial air velocity are the main variables in the separation of the different fractions. In this way an efficient separation is achieved by avoiding the environmental contamination coupled with the possible utilization of the different fractions obtained. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. A Review of Post and Core Application with Emphasize on Non Metallic Posts

    Directory of Open Access Journals (Sweden)

    Shahroodi MH

    2001-05-01

    Full Text Available Many different methods are suggested to restore endodontically treated teeth. Prefabricated posts can not be indicated for all teeth and cast posts require extra time and cost. In addition, with the introduction of full ceramic restorations, achieving the ideal esthetic with metal post underneath them may be problematic or impossible because the darkness of the metallic posts may show through the highly translucent all ceramic restorations. In this article the review of litature and describiton of applied methods of different procedure in restoring the root canal therapied teeth and few techniques of non metallic posts fabrication such as fiber reinforced composite and zirconium oxide posts have been described.

  18. [An optical-fiber-sensor-based spectrophotometer for soil non-metallic nutrient determination].

    Science.gov (United States)

    He, Dong-xian; Hu, Juan-xiu; Lu, Shao-kun; He, Hou-yong

    2012-01-01

    In order to achieve rapid, convenient and efficient soil nutrient determination in soil testing and fertilizer recommendation, a portable optical-fiber-sensor-based spectrophotometer including immersed fiber sensor, flat field holographic concave grating, and diode array detector was developed for soil non-metallic nutrient determination. According to national standard of ultraviolet and visible spectrophotometer with JJG 178-2007, the wavelength accuracy and repeatability, baseline stability, transmittance accuracy and repeatability measured by the prototype instrument were satisfied with the national standard of III level; minimum spectral bandwidth, noise and excursion, and stray light were satisfied with the national standard of IV level. Significant linear relationships with slope of closing to 1 were found between the soil available nutrient contents including soil nitrate nitrogen, ammonia nitrogen, available phosphorus, available sulfur, available boron, and organic matter measured by the prototype instrument compared with that measured by two commercial single-beam-based and dual-beam-based spectrophotometers. No significant differences were revealed from the above comparison data. Therefore, the optical-fiber-sensor-based spectrophotometer can be used for rapid soil non-metallic nutrient determination with a high accuracy.

  19. Solution behavior of hydrogen isotopes and other non-metallic elements in liquid lithium

    Energy Technology Data Exchange (ETDEWEB)

    Maroni, V.A.; Calaway, W.F.; Veleckis, E.; Yonco, R.M.

    1976-01-01

    Results of experimental studies to measure selected thermodynamic properties for systems of lithium with non-metallic elements are reported. Investigations of the Li-H, Li-D, and Li-T systems have led to the elucidation of the dilute solution behavior and the H/D/T isotope effects. In the case of the Li-H and Li-D systems, the principal features of the respective phase diagrams have been delineated. The solubility of Li-D in liquid lithium has been measured down to 200/sup 0/C. The solubility of Li/sub 3/N in liquid lithium and the thermal decomposition of Li/sub 3/N have also been studied. From these data, the free energy of formation of Li/sub 3/N and the Sieverts' constant for dissolution of nitrogen in lithium have been determined. Based on studies of the distribution of non-metallic elements between liquid lithium and selected molten salts, it appears that molten salt extraction offers promise as a means of removing these impurity elements (e.g., H, D, T, O, N, C) from liquid lithium.

  20. Bacterial assimilation reduction of iron in the treatment of non-metallics

    Directory of Open Access Journals (Sweden)

    Peter Malachovský

    2005-11-01

    Full Text Available Natural non-metallics, including granitoide and quartz sands, often contain iron which decreases the whiteness of these raw materials. Insoluble Fe3+ in these samples could be reduced to soluble Fe2+ by bacteria of Bacillus spp. and Saccharomyces spp. The leaching effect, observed by the measurement of Fe2+concentration in a solution, showed higher activities of a bacterial kind isolated from the Bajkal lake and also by using of yeast Saccharomyces sp. during bioleaching of quartz sands. However, allkinds of Bacillus spp. isolated from the Slovak deposit and from Bajkal lake were very active in the iron reduction during bioleaching of the feldspar raw material. This metal was efficiently removed from quartz sands as documented by the Fe2O3 decrease (from 0,317 % to 0,126 % and from feldpars raw materials by the Fe2O3 decrease (from 0,288 % to 0,115 % after bioleaching. The whiteness of these non-metallics was increased during a visual comparison of samples before and after bioleaching but samples contain selected magnetic particles. A removal of iron as well as a release of iron minerals from silicate matrix should increase the effect of the magnetic separation and should give a product which is suitable for industrial applications.

  1. PVC-based composite material containing recycled non-metallic printed circuit board (PCB) powders.

    Science.gov (United States)

    Wang, Xinjie; Guo, Yuwen; Liu, Jingyang; Qiao, Qi; Liang, Jijun

    2010-12-01

    The study is directed to the use of non-metallic powders obtained from comminuted recycled paper-based printed circuit boards (PCBs) as an additive to polyvinyl chloride (PVC) substrate. The physical properties of the non-metallic PCB (NMPCB) powders were measured, and the morphological, mechanical and thermal properties of the NMPCB/PVC composite material were investigated. The results show that recycled NMPCB powders, when added below a threshold, tended to increase the tensile strength and bending strength of PVC. When 20 wt% NMPCB powders (relative to the substrate PVC) of an average diameter of 0.08 mm were added, the composite tensile strength and bending strength reached 22.6 MPa and 39.83 MPa, respectively, representing 107.2% and 123.1% improvement over pure PVC. The elongation at break of the composite material reached 151.94% of that of pure PVC, while the Vicat softening temperature of the composite material did not increase significantly compared to the pure PVC. The above results suggest that paper-based NMPCB powders, when used at appropriate amounts, can be effective for toughening PVC. Thus, this study suggests a new route for reusing paper-based NMPCB, which may have a significant beneficial environmental impact.

  2. A Fully Non-Metallic Gas Turbine Engine Enabled by Additive Manufacturing

    Science.gov (United States)

    Grady, Joseph E.; Halbig, Michael C.; Singh, Mrityunjay

    2015-01-01

    In a NASA Aeronautics Research Institute (NARI) sponsored program entitled "A Fully Non-Metallic Gas Turbine Engine Enabled by Additive Manufacturing", evaluation of emerging materials and additive manufacturing technologies was carried out. These technologies may enable fully non-metallic gas turbine engines in the future. This paper highlights the results of engine system trade studies which were carried out to estimate reduction in engine emissions and fuel burn enabled due to advanced materials and manufacturing processes. A number of key engine components were identified in which advanced materials and additive manufacturing processes would provide the most significant benefits to engine operation. In addition, feasibility of using additive manufacturing technologies to fabricate gas turbine engine components from polymer and ceramic matrix composite were demonstrated. A wide variety of prototype components (inlet guide vanes (IGV), acoustic liners, engine access door) were additively manufactured using high temperature polymer materials. Ceramic matrix composite components included first stage nozzle segments and high pressure turbine nozzle segments for a cooled doublet vane. In addition, IGVs and acoustic liners were tested in simulated engine conditions in test rigs. The test results are reported and discussed in detail.

  3. X-ray detection of ingested non-metallic foreign bodies.

    Science.gov (United States)

    Saps, Miguel; Rosen, John M; Ecanow, Jacob

    2014-05-08

    To determine the utility of X-ray in identifying non-metallic foreign body (FB) and assess inter-radiologist agreement in identifying non-metal FB. Focus groups of nurses, fellows, and attending physicians were conducted to determine commonly ingested objects suitable for inclusion. Twelve potentially ingested objects (clay, plastic bead, crayon, plastic ring, plastic army figure, glass bead, paperclip, drywall anchor, eraser, Lego™, plastic triangle toy, and barrette) were embedded in a gelatin slab placed on top of a water-equivalent phantom to simulate density of a child's abdomen. The items were selected due to wide availability and appropriate size for accidental pediatric ingestion. Plain radiography of the embedded FBs was obtained. Five experienced radiologists blinded to number and types of objects were asked to identify the FBs. The radiologist was first asked to count the number of items that were visible then to identify the shape of each item and describe it to a study investigator who recorded all responses. Overall inter-rater reliability was analyzed using percent agreement and κ coefficient. We calculated P value to assess the probability of error involved in accepting the κ value. Fourteen objects were radiographed including 12 original objects and 2 duplicates. The model's validity was supported by clear identification of a radiolucent paperclip as a positive control, and lack of identification of plastic beads (negative control) despite repeated inclusion. Each radiologist identified 7-9 of the 14 objects (mean 8, 67%). Six unique objects (50%) were identified by all radiologists and four unique objects (33%) were not identified by any radiologist (plastic bead, Lego™, plastic triangle toy, and barrette). Identification of objects that were not present, false-positives, occurred 1-2 times per radiologist (mean 1.4). An additional 17% of unique objects were identified by less than half of the radiologists. Agreement between radiologists was

  4. Calculating the Carrying Capacity of Flexural Prestressed Concrete Beams with Non-Metallic Reinforcement

    Directory of Open Access Journals (Sweden)

    Mantas Atutis

    2011-04-01

    Full Text Available The article reviews moment resistance design methods of prestressed concrete beams with fibre-reinforced polymer (FRP reinforcement. FRP tendons exhibit linear elastic response to rupture without yielding and thus failure is expected to be brittle. The structural behaviour of beams prestressed with FRP tendons is different from beams with traditional steel reinforcement. Depending on the reinforcement ratio, the flexural behaviour of the beam can be divided into several groups. The numerical results show that depending on the nature of the element failure, moment resistance calculation results are different by using reviewed methods. It was found, that the use of non-metallic reinforcement in prestressed concrete structures is effective: moment capacity is about 5% higher than that of the beams with conventional steel reinforcement.Article in Lithuanian

  5. The share of non-metallic inclusions in high-grade steel for machine parts

    Directory of Open Access Journals (Sweden)

    T. Lipiński

    2010-10-01

    Full Text Available The aim of this work was to compare the differences in the purity steel in the dimensions of inclusion particles as dependent on various steel production processes. The experimental material consisted of semi-finished products of high-grade, medium-carbon constructional steel with: manganese, chromium, nickel, molybdenum and boron. The impurity content of steel was low as phosphorus and sulphur levels did not exceed 0.025%. The experimental material consisted of steel products obtained in three metallurgical processes: electric, electric with argon refining and oxygen converter with vacuum degassing of steel. Billet samples were collected to determine: chemical composition, relative volume of non-metallic inclusions, dimensions of impurities. The results were processed and presented in graphic form.

  6. Morphology and Orientation Selection of Non-metallic Inclusions in Electrified Molten Metal

    Science.gov (United States)

    Zhao, Z. C.; Qin, R. S.

    2017-10-01

    The effect of electric current on morphology and orientation selection of non-metallic inclusions in molten metal has been investigated using theoretical modeling and numerical calculation. Two geometric factors, namely the circularity ( fc ) and alignment ratio ( fe ) were introduced to describe the inclusions shape and configuration. Electric current free energy was calculated and the values were used to determine the thermodynamic preference between different microstructures. Electric current promotes the development of inclusion along the current direction by either expatiating directional growth or enhancing directional agglomeration. Reconfiguration of the inclusions to reduce the system electric resistance drives the phenomena. The morphology and orientation selection follow the routine to reduce electric free energy. The numerical results are in agreement with our experimental observations.

  7. Nuclide, metal and non metal levels in percolated water from soils fertilized with phosphogypsum

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Camilla Bof; Knupp, Eliana Aparecida Nonato; Palmieri, Helena E.L.; Jacomino, Vanusa Maria Feliciano, E-mail: cgbs@cdtn.b [Nuclear Technology Development Center (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Taddei, Maria Helena; Ciqueira, Maria Celia [Pocos de Caldas Lab., (LAPOC/CNEN), Pocos de Caldas, MG (Brazil)

    2009-07-01

    Systematic generation of residues is more and more worrying in today.s world; adequate storage and reutilization are of great importance. Since generation of residues has become impossible to avoid, the possibility of reuse must be studied and researched. An example of these residues is phosphogypsum, which is generated in phosphoric acid production at the rate of around 4.8 tons for each ton of phosphoric acid produced. Many studies seek to reuse phosphogypsum in agriculture as a source of calcium and sulfur, potassium or aluminum, especially in soils from Brazil's cerrado regions. Though phosphogypsum is mainly composed of dehydrated calcium sulfate, it can have high levels of heavy metals, non metals (As and Se), fluorides and natural radionuclides. Thus, its uncontrolled use as a soil conditioner can lead to contamination of underground water. (author)

  8. Analysis and simulation of non-metallic inclusions in spheroidal graphite iron

    Science.gov (United States)

    Pustal, B.; Schelnberger, B.; Bührig-Polaczek, A.

    2016-03-01

    Non-metallic inclusions in spheroidal cast iron (SGI) reduce fatigue strength and yield strength. This type of inclusion usually accumulates at grain boundaries. Papers addressing this topic show the overall impact of both the fraction of so-called white (carbides) and black (non-metallic) inclusions on mechanical properties. In the present work we focus on the origin and the formation conditions of black Mg-bearing inclusions, further distinguishing between Si-bearing and non-Si-bearing Mg inclusions. The formation was simulated applying thermodynamic approaches. Moreover, appropriate experiments have been carried out and a large number of particles have been studied applying innovative feature analysis with regard to shape, size, and composition. Magnesium silicates are predicted at elevated oxygen concentrations, whereas at low levels of oxygen sulphides and carbides appear at a late stage of solidification. Experiments with three consecutive flow obstacles show that the amount of magnesium silicates decrease after each of the three obstacles, whereas the fraction of non-Si-bearing inclusions remains approximately constant. The size of inclusions divides in halves over the flow path and the number of particles increases accordingly. We point out that based on feature analysis Mg-O-C bearing inclusion show disadvantageous form factors for which reason this kind of inclusions may be extremely harmful in terms of crack initiation. All results obtained indicate that magnesium silicates are entrapped on mould filling, whereas Mg-(O, C, S, P, N) bearing particles are precipitates at late stages of solidification. Consequently, the only avoidance strategy is setting up optimum retained magnesium content.

  9. Influence of non-metallic inclusions on the strength properties of screws made of 35B2+Cr steel after softening

    OpenAIRE

    Krawczyk, J.; Pawłowski, B

    2012-01-01

    Purpose: This paper presents the results of the research on the influence of non-metallic inclusions on strength properties of 35B2+Cr steel screws.Design/methodology/approach: The investigations were carried out on screws after softening. The investigated steels with different fraction of non-metallic inclusions were delivered by three different suppliers.Findings: It was proved, that in spite of the level of fraction of non-metallic inclusions compatible with the corresponding standards, th...

  10. The diesel exhaust in miners study: IV. Estimating historical exposures to diesel exhaust in underground non-metal mining facilities.

    NARCIS (Netherlands)

    Vermeulen, R.; Coble, J.B.; Lubin, J.H.; Portengen, L.; Blair, A.; Attfield, M.D.; Silverman, D.T.; Stewart, P.A.

    2010-01-01

    We developed quantitative estimates of historical exposures to respirable elemental carbon (REC) for an epidemiologic study of mortality, including lung cancer, among diesel-exposed miners at eight non-metal mining facilities [the Diesel Exhaust in Miners Study (DEMS)]. Because there were no histori

  11. Lipophilic super-absorbent polymer gels as surface cleaners for oil and grease from metal and non-metal surfaces

    Science.gov (United States)

    The objective of this research is to develop a new cleaning technology based on lipophilic super-absorbent swelling gels for the removal of oil, grease and particulate matters from metal and non-metal surfaces. It is desired that the cleaner is in solid form and is VOC-exempt, HAP-free, non-toxic, n...

  12. Super-Absorbent polymer gels for oil and grease removal from metal and non-metal surfaces

    Science.gov (United States)

    The objective of this research is to develop a new surface cleaning technology for removal of oil, grease and particulate matters from metal and non-metal surfaces. It is desired that the cleaner is in solid form and is VOC-exempt, HAP-free, non-toxic, non-corrosive, non-ozone depleting, recyclable...

  13. Metals, non-metals and PCB in electrical and electronic waste--actual levels in Switzerland.

    Science.gov (United States)

    Morf, Leo S; Tremp, Josef; Gloor, Rolf; Schuppisser, Felix; Stengele, Markus; Taverna, Ruedi

    2007-01-01

    The chemical composition of waste of small electrical and electronic equipment (s-WEEE), a rapidly growing waste stream, was determined for selected metals (Cu, Sb, Hg etc.) and non-metals (Cl, Br, P) and PCBs. During a 3-day experiment, all output products and the s-WEEE input mass flows in a WEEE recycling plant were measured. Only output products were sampled and analyzed. Material balances were established, applying substance flow analysis (SFA). Transfer coefficients for the selected substances were also determined. The results demonstrate the capability of SFA to determine the composition of the highly heterogeneous WEEE for most substances with rather low uncertainty (2 sigma +/- 30%). The results confirm the growing importance of s-WEEE regarding secondary resource metals and potential toxic substances. Nowadays, the thirty times smaller s-WEEE turns over larger flows for many substances, compared to municipal solid waste. Transfer coefficient results serve to evaluate the separation efficiency of the recycling process and confirm--with the exception of PCB and Hg--the limitation of hand-sorting and mechanical processing to separate pollutants (Cd, Pb, etc.) out of reusable fractions. Regularly applied SFA would serve to assess the efficacy of legislative, organizational and technical measures on the WEEE.

  14. Absorption of non-metallic inclusions by steelmaking slags—a review

    Directory of Open Access Journals (Sweden)

    Bruno Henrique Reis

    2014-04-01

    Full Text Available The formation of non-metallic inclusions during steelmaking is inevitable and, when not properly controlled, can cause performance and production problems. Slag is one of the resources available to carry out this control. In steelmaking, it is generally understood that inclusions are naturally absorbed by slag when flotation is sufficient. However, separation and dissolution may define the inclusion absorption capacity of slag. The discussion in this review explains the relationship between separation and the contact angle at the steel/inclusion interface, which differentiates the mechanism from liquid and solid inclusions. Whereas liquid particles show more predictable behavior in experimental observations, thermodynamic analysis is necessary in order to describe the removal of solid particles. Among other findings, it is evident that slag viscosity and the formation of compounds at the inclusion/slag interface strongly influence inclusion dissolution capacity. Following a detailed description of findings in the literature, this review considers the most influential factors to aid in optimizing slags for inclusion absorption.

  15. Strength and deformability of concrete beams reinforced by non-metallic fiber and composite rebar

    Science.gov (United States)

    Kudyakov, K. L.; Plevkov, V. S.; Nevskii, A. V.

    2015-01-01

    Production of durable and high-strength concrete structures with unique properties has always been crucial. Therefore special attention has been paid to non-metallic composite and fiber reinforcement. This article describes the experimental research of strength and deformability of concrete beams with dispersed and core fiber-based reinforcement. As composite reinforcement fiberglass reinforced plastic rods with diameters 6 mm and 10 mm are used. Carbon and basalt fibers are used as dispersed reinforcement. The developed experimental program includes designing and production of flexural structures with different parameters of dispersed fiber and composite rebar reinforcement. The preliminary testing of mechanical properties of these materials has shown their effectiveness. Structures underwent bending testing on a special bench by applying flexural static load up to complete destruction. During the tests vertical displacements were recorded, as well as value of actual load, slippage of rebars in concrete, crack formation. As a result of research were obtained structural failure and crack formation graphs, value of fracture load and maximum displacements of the beams at midspan. Analysis of experimental data showed the effectiveness of using dispersed reinforcement of concrete and the need for prestressing of fiberglass composite rebar.

  16. Stepped-Frequency Ground-Penetrating Radar for Detection of Small Non-metallic Buried Objects

    DEFF Research Database (Denmark)

    Jakobsen, Kaj Bjarne; Sørensen, Helge Bjarup Dissing; Nymann, Ole

    1997-01-01

    to an HP8753C Network Analyzer through a 5 m long Sucoflex coaxial cable. The data are collected automatically using an HPIB interface. The collected data contains both the amplitude and phase information of the reflection coefficient. Data are measured at up to a maximum of 401 different frequencies...... at each measurement point using a mesh-grid with a resolution down to 1 mm by 1 mm. The size of the scan area is 1410 mm by 210 mm. Measurements have been performed on loamy soil containing a buried M-56, a non-metallic AP-mine, and various other mine-like objects made of solid plastic, brass, aluminum......, steel, and wood. The presented results are based on probe-data measured at 100 different frequencies at each measurement point and a coarser mesh-grid of 10 mm by 10 mm, since it is found that less probe-data is needed. Our experiments show that even less amount of probe-data may be necessary....

  17. A Fully Non-Metallic Gas Turbine Engine Enabled by Additive Manufacturing

    Science.gov (United States)

    Grady, Joseph E.

    2015-01-01

    The Non-Metallic Gas Turbine Engine project, funded by NASA Aeronautics Research Institute, represents the first comprehensive evaluation of emerging materials and manufacturing technologies that will enable fully nonmetallic gas turbine engines. This will be achieved by assessing the feasibility of using additive manufacturing technologies to fabricate polymer matrix composite and ceramic matrix composite turbine engine components. The benefits include: 50 weight reduction compared to metallic parts, reduced manufacturing costs, reduced part count and rapid design iterations. Two high payoff metallic components have been identified for replacement with PMCs and will be fabricated using fused deposition modeling (FDM) with high temperature polymer filaments. The CMC effort uses a binder jet process to fabricate silicon carbide test coupons and demonstration articles. Microstructural analysis and mechanical testing will be conducted on the PMC and CMC materials. System studies will assess the benefits of fully nonmetallic gas turbine engine in terms of fuel burn, emissions, reduction of part count, and cost. The research project includes a multidisciplinary, multiorganization NASA - industry team that includes experts in ceramic materials and CMCs, polymers and PMCs, structural engineering, additive manufacturing, engine design and analysis, and system analysis.

  18. 半柔性路面负载纳米TiO2降解汽车尾气技术%The Technology of Degradation Car Tail Gas Through the Method of Nano-TiO2 Immobilized on the Semi-flexible Pavement

    Institute of Scientific and Technical Information of China (English)

    张龙; 葛折圣

    2014-01-01

    It is one of the most important contents of the energy conservation and emission reduction in transportation to deal with the automobile exhaust pollutants. In this essay the practical method of nano-TiO2 immobilized on the semi-flexible pavement was put forward through the study of structural characteristics of the semi-flexible pavement and principles of the nanometer Ti02 photo-catalysis. Sustainable use of the catalyst can be achieved through indirect load of glass beads. The performance of antiskid and wear resistance can be also achieved. And the durability of nano-TiO2 catalysis will be improved too. The inorganic acid of the ultimate product of the reaction can be removed from the surface of catalysis after neutralization reaction of alkaline cement mud of the semi-flexible pavement. This is good for the recycling of catalysis. This technology can be widely used in urban roads, highways and some special pavements. Great contributions will be made in the traffic construction mode of resource saving, environmental friendly and sustainable development. Therefore, there is a wide popularized significance.%汽车尾气污染物的治理是交通运输“节能减排”工作的重要内容之一。纳米TiO2可降解汽车尾气,但如何使纳米TiO2与路面结合?通过对半柔性路面的结构特点与纳米TiO2光催化原理的研究,提出半柔性路面负载纳米TiO2的实用方法,通过玻璃微珠的间接负载以达到催化剂能够可持续利用的目的。同时解决了路面的抗滑,抗磨等性能。提高了纳米TiO2催化剂的耐久性能,通过半柔性路面的碱性水泥浆的中和反应,去除了催化剂表面附着的反应的终级产物无机酸,有利于催化剂的循环使用。可广泛应用于城市道路,高速公路道路与一些特殊路段中。为实践“资源节约,环境友好”和可持续发展的交通建设模式做出贡献,具有广阔的推广意义。

  19. A Fully Non-metallic Gas Turbine Engine Enabled by Additive Manufacturing

    Science.gov (United States)

    Grady, Joseph E.

    2014-01-01

    The Non-Metallic Gas Turbine Engine project, funded by NASA Aeronautics Research Institute (NARI), represents the first comprehensive evaluation of emerging materials and manufacturing technologies that will enable fully nonmetallic gas turbine engines. This will be achieved by assessing the feasibility of using additive manufacturing technologies for fabricating polymer matrix composite (PMC) and ceramic matrix composite (CMC) gas turbine engine components. The benefits of the proposed effort include: 50 weight reduction compared to metallic parts, reduced manufacturing costs due to less machining and no tooling requirements, reduced part count due to net shape single component fabrication, and rapid design change and production iterations. Two high payoff metallic components have been identified for replacement with PMCs and will be fabricated using fused deposition modeling (FDM) with high temperature capable polymer filaments. The first component is an acoustic panel treatment with a honeycomb structure with an integrated back sheet and perforated front sheet. The second component is a compressor inlet guide vane. The CMC effort, which is starting at a lower technology readiness level, will use a binder jet process to fabricate silicon carbide test coupons and demonstration articles. The polymer and ceramic additive manufacturing efforts will advance from monolithic materials toward silicon carbide and carbon fiber reinforced composites for improved properties. Microstructural analysis and mechanical testing will be conducted on the PMC and CMC materials. System studies will assess the benefits of fully nonmetallic gas turbine engine in terms of fuel burn, emissions, reduction of part count, and cost. The proposed effort will be focused on a small 7000 lbf gas turbine engine. However, the concepts are equally applicable to large gas turbine engines. The proposed effort includes a multidisciplinary, multiorganization NASA - industry team that includes experts in

  20. Detection of Non-metallic Inclusions in Centrifugal Continuous Casting Steel Billets

    Science.gov (United States)

    Wang, Qiangqiang; Zhang, Lifeng; Seetharaman, Sridhar; Yang, Shufeng; Yang, Wen; Wang, Yi

    2016-06-01

    In the current study, automated particle analysis was employed to detect non-metallic inclusions in steel during a centrifugal continuous casting process of a high-strength low alloy steel. The morphology, composition, size, area fraction, amount, and spatial distribution of inclusions in steel were obtained. Etching experiment was performed to reveal the dendrite structure of the billet and to discuss the effect of centrifugal force on the distribution of oxide inclusions in the final solidified steel by comparing the solidification velocity with the critical velocity reported in literature. It was found that the amount of inclusions was highest in samples from the tundish (~250 per mm2), followed by samples from the mold (~200 per mm2), and lowest in billet samples (~86 per mm2). In all samples, over 90 pct of the inclusions were smaller than 2μm. In steel billets, the content of oxides, dual-phase oxide-sulfides, and sulfides in inclusions were found to be 10, 30, and 60 pct, respectively. The dual-phase inclusions were oxides with sulfides precipitated on the outer surface. Oxide inclusions consisted of high Al2O3 and high MnO which were solid at the molten steel temperature, implying that the calcium treatment was insufficient. Small oxide inclusions very uniformly distributed on the cross section of the billet, while there were more sulfide inclusions showing a banded structure at the outside 25 mm layer of the billet. The calculated solidification velocity was higher than the upper limit at which inclusions were entrapped by the solidifying front, revealing that for oxide inclusions smaller than 8μm in this study, the centrifugal force had little influence on its final distribution in billets. Instead, oxide inclusions were rapidly entrapped by solidifying front.

  1. Recycling of non-metallic fractions from waste electrical and electronic equipment (WEEE): a review.

    Science.gov (United States)

    Wang, Ruixue; Xu, Zhenming

    2014-08-01

    The world's waste electrical and electronic equipment (WEEE) consumption has increased incredibly in recent decades, which have drawn much attention from the public. However, the major economic driving force for recycling of WEEE is the value of the metallic fractions (MFs). The non-metallic fractions (NMFs), which take up a large proportion of E-wastes, were treated by incineration or landfill in the past. NMFs from WEEE contain heavy metals, brominated flame retardant (BFRs) and other toxic and hazardous substances. Combustion as well as landfill may cause serious environmental problems. Therefore, research on resource reutilization and safe disposal of the NMFs from WEEE has a great significance from the viewpoint of environmental protection. Among the enormous variety of NMFs from WEEE, some of them are quite easy to recycle while others are difficult, such as plastics, glass and NMFs from waste printed circuit boards (WPCBs). In this paper, we mainly focus on the intractable NMFs from WEEE. Methods and technologies of recycling the two types of NMFs from WEEE, plastics, glass are reviewed in this paper. For WEEE plastics, the pyrolysis technology has the lowest energy consumption and the pyrolysis oil could be obtained, but the containing of BFRs makes the pyrolysis recycling process problematic. Supercritical fluids (SCF) and gasification technology have a potentially smaller environmental impact than pyrolysis process, but the energy consumption is higher. With regard to WEEE glass, lead removing is requisite before the reutilization of the cathode ray tube (CRT) funnel glass, and the recycling of liquid crystal display (LCD) glass is economically viable for the containing of precious metals (indium and tin). However, the environmental assessment of the recycling process is essential and important before the industrialized production stage. For example, noise and dust should be evaluated during the glass cutting process. This study could contribute

  2. Low modulus Ti-Nb-Hf alloy for biomedical applications.

    Science.gov (United States)

    González, M; Peña, J; Gil, F J; Manero, J M

    2014-09-01

    β-Type titanium alloys with a low elastic modulus are a potential strategy to reduce stress shielding effect and to enhance bone remodeling in implants used to substitute failed hard tissue. For biomaterial application, investigation on the mechanical behavior, the corrosion resistance and the cell response is required. The new Ti25Nb16Hf alloy was studied before and after 95% cold rolling (95% C.R.). The mechanical properties were determined by tensile testing and its corrosion behavior was analyzed by potentiostatic equipment in Hank's solution at 37°C. The cell response was studied by means of cytotoxicity evaluation, cell adhesion and proliferation measurements. The stress-strain curves showed the lowest elastic modulus (42GPa) in the cold worked alloy and high tensile strength, similar to that of Ti6Al4V. The new alloy exhibited better corrosion resistance in terms of open circuit potential (EOCP), but was similar in terms of corrosion current density (iCORR) compared to Ti grade II. Cytotoxicity studies revealed that the chemical composition of the alloy does not induce cytotoxic activity. Cell studies in the new alloy showed a lower adhesion and a higher proliferation compared to Ti grade II presenting, therefore, mechanical features similar to those of human cortical bone and, simultaneously, a good cell response.

  3. Low modulus Ti–Nb–Hf alloy for biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    González, M., E-mail: Marta.Gonzalez.Colominas@upc.edu [Department of Materials Science and Metallurgy, Universitat Politècnica de Catalunya (UPC), Avda. Diagonal 647, 08028 Barcelona (Spain); Materials Science, Elisava Escola Superior de Disseny i Enginyeria de Barcelona, La Rambla 30-32, 08002 Barcelona (Spain); Peña, J. [Department of Materials Science and Metallurgy, Universitat Politècnica de Catalunya (UPC), Avda. Diagonal 647, 08028 Barcelona (Spain); Materials Science, Elisava Escola Superior de Disseny i Enginyeria de Barcelona, La Rambla 30-32, 08002 Barcelona (Spain); Gil, F.J.; Manero, J.M. [Department of Materials Science and Metallurgy, Universitat Politècnica de Catalunya (UPC), Avda. Diagonal 647, 08028 Barcelona (Spain); Ciber-BBN (Spain)

    2014-09-01

    β-Type titanium alloys with a low elastic modulus are a potential strategy to reduce stress shielding effect and to enhance bone remodeling in implants used to substitute failed hard tissue. For biomaterial application, investigation on the mechanical behavior, the corrosion resistance and the cell response is required. The new Ti25Nb16Hf alloy was studied before and after 95% cold rolling (95% C.R.). The mechanical properties were determined by tensile testing and its corrosion behavior was analyzed by potentiostatic equipment in Hank's solution at 37 °C. The cell response was studied by means of cytotoxicity evaluation, cell adhesion and proliferation measurements. The stress–strain curves showed the lowest elastic modulus (42 GPa) in the cold worked alloy and high tensile strength, similar to that of Ti6Al4V. The new alloy exhibited better corrosion resistance in terms of open circuit potential (E{sub OCP}), but was similar in terms of corrosion current density (i{sub CORR}) compared to Ti grade II. Cytotoxicity studies revealed that the chemical composition of the alloy does not induce cytotoxic activity. Cell studies in the new alloy showed a lower adhesion and a higher proliferation compared to Ti grade II presenting, therefore, mechanical features similar to those of human cortical bone and, simultaneously, a good cell response. - Highlights: • Presents low elastic modulus and high strength and elastic deformability. • Exhibits good biocompatibility in terms of cytotoxicity and cell response. • Corrosion resistance of this alloy is good, similar to that of Ti grade II. • Potential candidate for implants used to substitute failed hard tissue.

  4. Low-modulus PMMA bone cement modified with castor oil.

    Science.gov (United States)

    López, Alejandro; Hoess, Andreas; Thersleff, Thomas; Ott, Marjam; Engqvist, Håkan; Persson, Cecilia

    2011-01-01

    Some of the current clinical and biomechanical data suggest that vertebroplasty causes the development of adjacent vertebral fractures shortly after augmentation. These findings have been attributed to high injection volumes as well as high Young's moduli of PMMA bone cements compared to that of the osteoporotic cancellous bone. The aim of this study was to evaluate the use of castor oil as a plasticizer for PMMA bone cements. The Young's modulus, yield strength, maximum polymerization temperature, doughing time, setting time and the complex viscosity curves during curing, were determined. The cytotoxicity of the materials extracts was assessed on cells of an osteoblast-like cell line. The addition of up to 12 wt% castor oil decreased yield strength from 88 to 15 MPa, Young's modulus from 1500 to 446 MPa and maximum polymerization temperature from 41.3 to 25.6°C, without affecting the setting time. However, castor oil seemed to interfere with the polymerization reaction, giving a negative effect on cell viability in a worst-case scenario.

  5. Numerical analysis of the non-metallic inclusions distribution and separation in a two-strand tundish

    Directory of Open Access Journals (Sweden)

    T. Merder

    2013-04-01

    Full Text Available The tundish plays an important role in the challenging task of a “clean steel” production process. The flow of the liquid steel in tundish has a crucial influence on non-metallic inclusions distribution and separation. The article presents computational studies of non-metallic inclusions separation in a two-strand industrial tundish during steady-state casting. Tundish capacity is 7,5 t. First, flow structure in the tundish was investigated using water model of the industrial tundish in a 1:2 scale. The experimental results, regarding RTD characteristics were used to validate numerical model. With validated model, particle distribution and separation in the two-strand tundish were investigated numerically. For modelling the separation of particles at the fluid surface, a modified boundary condition has been implemented.

  6. An aviation security (AVSEC) screening demonstrator for the detection of non-metallic threats at 28-33 GHz

    Science.gov (United States)

    Salmon, Neil A.; Bowring, Nick; Hutchinson, Simon; Southgate, Matthew; O'Reilly, Dean

    2013-10-01

    The unique selling proposition of millimetre wave technology for security screening is that it provides a stand-off or portal scenario sensing capability for non-metallic threats. The capabilities to detect some non-metallic threats are investigated in this paper, whilst recommissioning the AVSEC portal screening system at the Manchester Metropolitan University. The AVSEC system is a large aperture (1.6 m) portal screening imager which uses spatially incoherent illumination at 28-33 GHz from mode scrambling cavities to illuminate the subject. The imaging capability is critically analysed in terms of this illumination. A novel technique for the measurement of reflectance, refractive index and extinction coefficient is investigated and this then use to characterise the signatures of nitromethane, hexane, methanol, bees wax and baking flour. Millimetre wave images are shown how these liquids in polycarbonate bottles and the other materials appear against the human body.

  7. Cleavage of hydrogen by activation at a single non-metal centre - towards new hydrogen storage materials.

    Science.gov (United States)

    Grabowski, Sławomir J

    2015-05-28

    Molecular surfaces of non-metal species are often characterized by both positive and negative regions of electrostatic potential (EP) at a non-metal centre. This centre may activate molecular hydrogen which further leads to the addition reaction. The positive EP regions at the non-metal centres correspond to σ-holes; the latter sites are enhanced by electronegative substituents. This is why the following simple moieties; PFH2, SFH, AsFH2, SeFH, BrF3, PF(CH3)2 and AsF(CH3)2, were chosen here to analyze the H2 activation and its subsequent splitting at the P, As, S, Se and Br centres. Also the reverse H-H bond reforming process is analyzed. MP2/aug-cc-pVTZ calculations were performed for systems corresponding to different stages of these processes. The sulphur centre in the SFH moiety is analyzed in detail since the potential barrier height for the addition reaction for this species is the lowest of the moieties analyzed here. The results of calculations show that the SFH + H2 → SFH3 reaction in the gas phase is endothermic but it is exothermic in polar solvents.

  8. Recycling of non-metallic fractions from waste electrical and electronic equipment (WEEE): A review

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ruixue; Xu, Zhenming, E-mail: zmxu@sjtu.edu.cn

    2014-08-15

    Highlights: • NMFs from WEEE were treated by incineration or land filling in the past. • Environmental risks such as heavy metals and BFRs will be the major problems during the NMFs recycling processes. • Methods and technologies of recycling the two types of NMFs from WEEE, plastics, glasses are reviewed. • More environmental impact assessment should be carried out to evaluate the environmental risks of the recycling products. - Abstract: The world’s waste electrical and electronic equipment (WEEE) consumption has increased incredibly in recent decades, which have drawn much attention from the public. However, the major economic driving force for recycling of WEEE is the value of the metallic fractions (MFs). The non-metallic fractions (NMFs), which take up a large proportion of E-wastes, were treated by incineration or landfill in the past. NMFs from WEEE contain heavy metals, brominated flame retardant (BFRs) and other toxic and hazardous substances. Combustion as well as landfill may cause serious environmental problems. Therefore, research on resource reutilization and safe disposal of the NMFs from WEEE has a great significance from the viewpoint of environmental protection. Among the enormous variety of NMFs from WEEE, some of them are quite easy to recycle while others are difficult, such as plastics, glass and NMFs from waste printed circuit boards (WPCBs). In this paper, we mainly focus on the intractable NMFs from WEEE. Methods and technologies of recycling the two types of NMFs from WEEE, plastics, glass are reviewed in this paper. For WEEE plastics, the pyrolysis technology has the lowest energy consumption and the pyrolysis oil could be obtained, but the containing of BFRs makes the pyrolysis recycling process problematic. Supercritical fluids (SCF) and gasification technology have a potentially smaller environmental impact than pyrolysis process, but the energy consumption is higher. With regard to WEEE glass, lead removing is requisite

  9. Numerical 2D and 3D Investigation of Non-Metallic (Glass, Carbon) Fiber Pull-Out Micromechanics 9in Concrete Matrix)

    OpenAIRE

    Khabaz, A; Krasņikovs, A; Kononova, O; Mačanovskis, A

    2010-01-01

    Short non-metallic (glass, carbon) fibre use for concrete disperse reinforcment is of particular interest, because of much higher fibre/matrix interface area value comparing to industrially produced steel fibres.

  10. Experimental and numerical investigation of concrete structures with metal and non-metal reinforcement at impulse loadings

    Science.gov (United States)

    Radchenko, P. A.; Batuev, S. P.; Radchenko, A. V.; Plevkov, V. S.; Kudyakov, K. L.

    2016-11-01

    Manufacturing durable and high-strength concrete structures has always been a relevant objective. Therefore special attention has been paid to non-metallic composite reinforcement. This paper considers experimental and numerical studies of nature of fracture and crack formation in concrete beams with rod composite reinforcement. Fiber glass rods, 6 mm in diameter, have been used as composite reinforcement. Concrete elements have been tested under dynamic load using special pile driver. The obtained results include patterns of fracture and crack formation, maximum load value and maximum element deflection. Comparative analysis of numerical and experimental studies has been held.

  11. Influence of Low-Alloy Cast Steel Modification on Primary Structure Refinement, Type and Shape of Non-Metallic Inclusions

    Directory of Open Access Journals (Sweden)

    Bartocha D.

    2015-04-01

    Full Text Available In the article there are presented methods and results of investigation which main aim were determination of influence of melting technology (gas extraction, vacuum refining, slag refining and extraction, deoxidation and degassing and type of used modifiers on the type and shape of non-metallic inclusions and the primary structure refining. Low alloy cast steel melted in laboratory conditions, in an inductive furnace was investigated. Additions of FeNb, FeV, FeTi and FeZr modifiers were applied. The contents of oxygen and nitrogen in obtained cast steel were determined.

  12. 非金属矿物在医药行业的应用与前景%Medicinal Application and Prospect of Non-metallic Mineral

    Institute of Scientific and Technical Information of China (English)

    鲍康德; 周春晖

    2012-01-01

    Deep procession of non-metallic mineral and application on bio-/medicinal area is a new high-technical industry. This paper summarizes the appl ication history and status in quo of non-metallic minerals in pharmaceutical industry; identification, classification and development tendency of non-metallic minerals for pharmaceutical use. The focus is to introduce the development history of non-metallic minerals for pharmaceutical use, and explore the application prospect of non-metallic minerals in pharmaceutical industry, so as to provide theory basis for sufficiently exploring the potential of non-metallic minerals.%非金属矿物深加工并被用于生物医药领域系高新技术产业.本文综述了非金属矿物的医药应用历史、现状;药用非金属矿物的鉴别、分类和发展趋势.重点介绍了非金属矿物的药用开发历程,并展望了非金属矿物在医药行业的应用前景,以期为充分发掘非金属矿物的潜能提供理论指导.

  13. Study on Non-Metallic Inclusions in Laser-Welded TRIP-Aided Nb-Microalloyed Steel

    Directory of Open Access Journals (Sweden)

    Grajcar A.

    2014-10-01

    Full Text Available The work concerns the studies on non-metallic inclusions occuring in laser-welded Si-Al TRIP steel containing Nb and Ti microadditions. Laser welding tests of 2 mm thick thermomechanically rolled sheets were carried out using keyhole welding and a solid-state laser. The results of laser welding in the air atmosphere for the heat input value of 0.048 kJ/mm are included. The distribution, type and chemical composition of non-metallic inclusions formed in the base metal, heat-affected zone, and fusion zone are analysed in detail. It was found that the base metal contains rare, fine oxysulphides. Their chemical composition was modified by rare earth elements. Numerous oxide inclusions of a various size and a chemical composition occur in the fusion zone. The dependence between a size of particles and their chemical composition was observed. A microstructure of steel was assessed using light microscopy and scanning electron microscopy techniques.

  14. Non-Metallic Inclusions and Hot-Working Behaviour of Advanced High-Strength Medium-Mn Steels

    Directory of Open Access Journals (Sweden)

    Grajcar A.

    2016-06-01

    Full Text Available The work addresses the production of medium-Mn steels with an increased Al content. The special attention is focused on the identification of non-metallic inclusions and their modification using rare earth elements. The conditions of the thermomechanical treatment using the metallurgical Gleeble simulator and the semi-industrial hot rolling line were designed for steels containing 3 and 5% Mn. Hot-working conditions and controlled cooling strategies with the isothermal holding of steel at 400°C were selected. The effect of Mn content on the hot-working behaviour and microstructure of steel was addressed. The force-energetic parameters of hot rolling were determined. The identification of structural constituents was performed using light microscopy and scanning electron microscopy methods. The addition of rare earth elements led to the total modification of non-metallic inclusions, i.e., they replaced Mn and Al forming complex oxysulphides. The Mn content in a range between 3 and 5% does not affect the inclusion type and the hot-working behaviour. In contrast, it was found that Mn has a significant effect on a microstructure.

  15. AES and SIMS analysis of non-metallic inclusions in a low-carbon chromium-steel.

    Science.gov (United States)

    Gammer, Katharina; Rosner, M; Poeckl, G; Hutter, H

    2003-05-01

    In the final step of secondary metallurgical steel processing, calcium is added. Besides Mg, Ca is the most powerful deoxidiser and desulfurisation agent. It reacts with dissolved oxygen and sulfur and reduces oxides and sulfides thereby forming non-metallic inclusions. Within this paper we present the analysis of such inclusions in a low-carbon chromium-steel. Depending on the time of quenching of the steel sample, different structures were revealed by REM, Auger and SIMS: If the steel was quenched immediately after Ca-addition, non-metallic inclusions that appeared to have "cavities" could be detected with SEM. SIMS investigations of these particles showed ring-shaped structures and revealed that the ring is made up of Al, Ca, Mg, O and S. No secondary ions however could be retrieved from the core inside the ring, thus leaving the nature of the "cavities" unclear. If the steel sample was quenched 3 min after Ca addition, inclusions did not have a ring-shaped structure but a compact one.

  16. Non-metal doped TiO2 nanotube arrays for high efficiency photocatalytic decomposition of organic species in water

    Science.gov (United States)

    Szkoda, Mariusz; Siuzdak, Katarzyna; Lisowska-Oleksiak, Anna

    2016-10-01

    Titanium dioxide is a well-known photoactive semiconductor with a variety of possible applications. The procedure of pollutant degradation is mainly performed using TiO2 powder suspension. It can also be exploited an immobilized catalyst on a solid support. Morphology and chemical doping have a great influence on TiO2 activity under illumination. Here we compare photoactivity of titania nanotube arrays doped with non-metal atoms: nitrogen, iodine and boron applied for photodegradation of organic dye - methylene blue and terephtalic acid. The doped samples act as a much better photocatalyst in the degradation process of methylene blue and lead to the formation of much higher amount of hydroxyl radicals (•OH) than undoped TiO2 nanotube arrays. The use of a catalyst active under solar light illumination in the form of thin films on a stable substrate can be scaled up for an industrial application.

  17. Effect of Non-metallic Inclusions in Fe-Al-Ti-O-N-S Alloy on Grain Size

    Science.gov (United States)

    Choi, Wonjin; Matsuura, Hiroyuki; Tsukihashi, Fumitaka

    2016-06-01

    The effect of characteristics of non-metallic inclusions in Fe-Al-Ti-O-N-S alloys with various compositions at 1473 K (1200 °C) on the microstructure was studied. The ASTM grain size number was determined in as-cast and heated samples by the optical microscopy, and the inclusion types in each sample were determined from composition analysis by field-emission scanning electron microscope with energy-dispersive spectroscopy. The TiN-based inclusions certainly had a positive effect on the grain refinement. On the other hand, TiS-based inclusions exhibited no influence on the decrease of grain size. In addition, the formation and evolution behavior of inclusions by heating solid-state Fe-Al-Ti-O-N-S alloys with those locations were clarified. A different change of inclusions in alloys was observed depending on the distribution and composition of inclusions.

  18. Characteristics and Modification of Non-metallic Inclusions in Titanium-Stabilized AISI 409 Ferritic Stainless Steel

    Science.gov (United States)

    Kruger, Dirk; Garbers-Craig, Andrie

    2017-06-01

    This study describes an investigation into the improvement of castability, final surface quality and formability of titanium-stabilized AISI 409 ferritic stainless steel on an industrial scale. Non-metallic inclusions found in this industrially produced stainless steel were first characterized using SEM-EDS analyses through the INCA-Steel software platform. Inclusions were found to consist of a MgO·Al2O3 spinel core, which acted as heterogeneous nucleation site for titanium solubility products. Plant-scale experiments were conducted to either prevent the formation of spinel, or to modify it by calcium treatment. Modification to spherical dual-phase spinel-liquid matrix inclusions was achieved with calcium addition, which eliminated submerged entry nozzle clogging for this grade. Complete modification to homogeneous liquid calcium aluminates was achieved at high levels of dissolved aluminum. A mechanism was suggested to explain the extent of modification achieved.

  19. Detection of Surface and Subsurface Cracks in Metallic and Non-Metallic Materials Using a Complementary Split-Ring Resonator

    Directory of Open Access Journals (Sweden)

    Ali Albishi

    2014-10-01

    Full Text Available Available microwave techniques for crack detection have some challenges, such as design complexity and working at a high frequency. These challenges make the sensing apparatus design complex and relatively very expensive. This paper presents a simple method for surface and subsurface crack detection in metallic and non-metallic materials based on complementary split-ring resonators (CSRRs. A CSRR sensor can be patterned on the ground plane of a microstrip line and fabricated using printed circuit board technology. Compared to available microwave techniques for sub-millimeter crack detection, the methods presented here show distinct advantages, such as high spatial resolution, high sensitivity and design simplicity. The response of the CSRR as a sensor for crack detection is studied and analysed numerically. Experimental validations are also presented.

  20. Characteristics and Modification of Non-metallic Inclusions in Titanium-Stabilized AISI 409 Ferritic Stainless Steel

    Science.gov (United States)

    Kruger, Dirk; Garbers-Craig, Andrie

    2017-02-01

    This study describes an investigation into the improvement of castability, final surface quality and formability of titanium-stabilized AISI 409 ferritic stainless steel on an industrial scale. Non-metallic inclusions found in this industrially produced stainless steel were first characterized using SEM-EDS analyses through the INCA-Steel software platform. Inclusions were found to consist of a MgO·Al2O3 spinel core, which acted as heterogeneous nucleation site for titanium solubility products. Plant-scale experiments were conducted to either prevent the formation of spinel, or to modify it by calcium treatment. Modification to spherical dual-phase spinel-liquid matrix inclusions was achieved with calcium addition, which eliminated submerged entry nozzle clogging for this grade. Complete modification to homogeneous liquid calcium aluminates was achieved at high levels of dissolved aluminum. A mechanism was suggested to explain the extent of modification achieved.

  1. Standard practice for process compensated resonance testing via swept sine input for metallic and Non-Metallic parts

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This practice describes a general procedure for using the process compensated resonance testing (PCRT) via swept sine input method to identify metallic and non-metallic parts’ resonant pattern differences that can be used to indentify parts with anomalies causing deficiencies in the expected performance of the part in service. This practice is intended for use with instruments capable of exciting, measuring, recording, and analyzing multiple whole body mechanical vibration resonant frequencies within parts exhibiting acoustical ringing in the audio, or ultrasonic, resonant frequency ranges, or both. PCRT is used in the presence of manufacturing process variance to distinguish acceptable parts from those containing significant anomalies in physical characteristics expected to significantly alter the performance. Such physical characteristics include, but are not limited to, cracks, voids, porosity, shrink, inclusions, discontinuities, grain and crystalline structure differences, density related anomalies...

  2. The uncertainties calculation of acoustic method for measurement of dissipative properties of heterogeneous non-metallic materials

    Directory of Open Access Journals (Sweden)

    Мaryna O. Golofeyeva

    2015-12-01

    Full Text Available The effective use of heterogeneous non-metallic materials and structures needs measurement of reliable values of dissipation characteristics, as well as common factors of their change during the loading process. Aim: The aim of this study is to prepare the budget for measurement uncertainty of dissipative properties of composite materials. Materials and Methods: The method used to study the vibrational energy dissipation characteristics based on coupling of vibrations damping decrement and acoustic velocity in a non-metallic heterogeneous material is reviewed. The proposed method allows finding the dependence of damping on vibrations amplitude and frequency of strain-stress state of material. Results: Research of the accuracy of measurement method during the definition of decrement attenuation of fluctuations in synthegran was performed. The international approach for evaluation of measurements quality is used. It includes the common practice international rules for uncertainty expression and their summation. These rules are used as internationally acknowledged confidence measure to the measurement results, which includes testing. The uncertainties budgeting of acoustic method for measurement of dissipative properties of materials were compiled. Conclusions: It was defined that there are two groups of reasons resulting in errors during measurement of materials dissipative properties. The first group of errors contains of parameters changing of calibrated bump in tolerance limits, displacement of sensor in repeated placement to measurement point, layer thickness variation of contact agent because of irregular hold-down of resolvers to control surface, inaccuracy in reading and etc. The second group of errors is linked with density and Poisson’s ratio measurement errors, distance between sensors, time difference between signals of vibroacoustic sensors.

  3. Effect of Acid-Soluble Aluminum on the Evolution of Non-metallic Inclusions in Spring Steel

    Science.gov (United States)

    Wang, Yong; Tang, Haiyan; Wu, Tuo; Wu, Guanghui; Li, Jingshe

    2017-04-01

    The content of acidic soluble aluminum in molten steel ([Al]s) is of significance to the control of total oxygen (TO), the formation of non-metallic inclusions, and the improvement of the surface quality of billets. Industrial trials and thermodynamic calculations were performed to study the effects of [Al]s content on the TO and the evolution of non-metallic inclusions in 60Si2Mn-Cr spring steel that was deoxidized by Si-Mn ((low aluminum process (LAP)) and Si-Mn-Al (high aluminum process (HAP)). The results show that the [Al]s contents in billets are within 0.0060 to 0.0069 mass pct in the LAP and 0.016 to 0.055 mass pct in the HAP. The TO content at each station of the LAP is higher than that in the HAP; the inclusions of billets were mainly of the CaO-Al2O3-SiO2 type in the former, and of the CaO-Al2O3-MgO and CaS-Al2O3-MgO types in the latter. A tendency is found that the higher the [Al]s, the easier it is to deviate from the low melting point region of the inclusion distribution and the larger the size of the inclusions. The relationships between [Al]s and the melting point of the oxide inclusions and the Al2O3 content in the oxide inclusions are also discussed in terms of experiment and calculation.

  4. Enhanced hydrogen desorption properties of magnesium hydride by coupling non-metal doping and nano-confinement

    Science.gov (United States)

    He, Daliang; Wang, Yulong; Wu, Chengzhang; Li, Qian; Ding, Weizhong; Sun, Chenghua

    2015-12-01

    Magnesium hydride (MgH2) offers excellent capacity to store hydrogen, but it suffers from the high desorption temperature (>283 °C for starting release hydrogen). In this work, we calculated the hydrogen desorption energy of Mg76H152 clusters with/without non-metal dopants by density functional theory method. Phosphorus (P), as identified as the best dopant, can reduce the reaction energy for releasing one hydrogen molecule from 0.75 eV (bulk MgH2) to 0.20 eV. Inspired by the calculation, P-doped ordered mesoporous carbon (CMK-3) was synthesized by one-step method and employed as the scaffold for loading MgH2 nanoparticles, forming MgH2@P/CMK-3. Element analysis shows that phosphorus dopants have been incorporated into the CMK-3 scaffold and magnesium and phosphorus elements are well-distributed in carbon scaffold hosts. Tests of hydrogen desorption confirmed that P-doping can remarkably enhance the hydrogen release properties of nanoconfined MgH2 at low temperature, specifically ˜1.5 wt. % H2 released from MgH2@P/CMK-3 below 200 °C. This work, based on the combination of computational calculations and experimental studies, demonstrated that the combined approach of non-metal doping and nano-confinement is promising for enhancing the hydrogen desorption properties of MgH2, which provides a strategy to address the challenge of hydrogen desorption from MgH2 at mild operational conditions.

  5. Energy Consumption and Carbon Dioxide Emissions of China’s Non-Metallic Mineral Products Industry: Present State, Prospects and Policy Analysis

    Directory of Open Access Journals (Sweden)

    Hui Hu

    2014-11-01

    Full Text Available China is the largest non-metallic mineral producer in the world and one of the key consumers of four major non-metallic mineral products, including cement, refractories, plate glass and ceramics. The non-metallic mineral products industry’s rapid growth has brought about a large demand for energy. The present study provides an overview of China’s non-metallic mineral products industry in terms of production, energy consumption and carbon dioxide emissions. In this industry, the energy efficiency is relatively low and the level of carbon dioxide emission is much higher than developed countries’ average. This study interprets the effects of some newly issued policies and analyses the influential factors in achieving energy conservation and emission reduction goals. It also discusses the prospects for saving energy and emission reduction in the industry. Retrofitting facilities and using new production technologies is imperative. Additionally, implementing market-based policies, promoting industrial transformation and effective international cooperation would help decrease carbon dioxide emissions and energy consumption.

  6. Effect of Calcium Treatment on Non-Metallic Inclusions in Ultra-Low Oxygen Steel Refined by High Basicity High Al2O3 Sla

    Institute of Scientific and Technical Information of China (English)

    YANG Jun; WANG Xin-hua; JIANG Min; WANG Wan-jun

    2011-01-01

    The influence of calcium treatment on non-metallic inclusions had been studied when control technology of refining top slag in ladle furnace was used in ultra-low oxygen steelmaking. A sufficient amount aluminium was added to experimental heats for final

  7. Effect of the structural parameters changes in the multi-strand tundish on the non-metallic inclusions distribution and separation

    Directory of Open Access Journals (Sweden)

    M. Warzecha

    2014-10-01

    Full Text Available The aim of presented studies was to investigate the fluid flow change and non-metallic inclusions removal changes due to tundish construction modifications. In presented study, numerical simulations were used. Numerical simulations are carried out with the finite-volume commercial code ANSYS Fluent. Steady-state casting conditions for the flow structure and the inclusions removal process are analysed.

  8. Deformation and fracture properties of metals with non-metallic inclusions; Verformung und Bruch von Metallen mit nichtmetallischen Einschluessen

    Energy Technology Data Exchange (ETDEWEB)

    Schmauder, S.; Soppa, E. [Stuttgart Univ. (Germany). Staatliche Materialpruefungsanstalt

    1998-12-31

    Microstructural effects due to formation of non-uniform lines of non-metallic inclusions in the matrix are examined with respect to their macro-, meso-, and micromechanical effects in the alloy Al(6061) reinforced by SiC inclusions. A comparative analysis of results obtained with various microstructures reveals essential differences in the formation of shear bands, stress peaks, and strain concentrations in the material structure. The maxima and the distribution of those field variables are determined not only by the arrangement of inclusions clusters in the stringers but also depend on the presence and number of single-particle inclusions in pure matrix material. The banding of the microstructure causes a strongly anisotropic behaviour in terms of stress and strain distributions. (orig./CB) [Deutsch] In diesem Beitrag werden Gefuegeeinfluesse aufgrund unterschiedlich starker zeiliger Anordnungen der Teilchen in der Matrix im Hinblick auf ihre makro-, meso- und mikromechanischen Auswirkungen am Beispiel einer SiC-teilchenverstaerkten Aluminiumlegierung Al(6061) untersucht. Ein Vergleich der Ergebnisse verschiedener Gefuege zeigt wesentliche Unterschiede hinsichtlich der Ausbildung von Scherbaendern, Spannungsspitzen und von Dehnungskonzentrationen im Werkstoffgefuege. Die Maxima und die Verteilung dieser Feldgroessen sind nicht nur abhaengig davon, wie die Teilchen in den Zeilen angeordnet sind, sondern auch davon, ob einzelne Teilchen in reinen Matrixbereichen vorhanden sind. Die Zeiligkeit des Gefueges fuehrt zu einem stark anisotropen Verhalten hinsichtlich Spannungs- und Dehnungsverteilungen. (orig.)

  9. Assessment of Different Turbulence Models for the Motion of Non-metallic Inclusion in Induction Crucible Furnace

    Science.gov (United States)

    Barati, H.; Wu, M.; Kharicha, A.; Ludwig, A.

    2016-07-01

    Turbulent fluid flow due to the electromagnetic forces in induction crucible furnace (ICF) is modeled using k-ɛ, k-ω SST and Large Eddy Simulation (LES) turbulence models. Fluid flow patterns calculated by different turbulence models and their effects on the motion of non-metallic inclusions (NMI) in the bulk melt have been investigated. Results show that the conventional k-ɛ model cannot solve the transient flow in ICF properly. With k-ω model transient flow and oscillation behavior of the flow pattern can be solved, and the motion of NMI can be tracked fairly well. LES model delivers the best modeling result on both details of the transient flow pattern and motion trajectories of NMI without the limitation of NMI size. The drawback of LES model is the long calculation time. Therefore, for general purpose to estimate the dynamic behavior of NMI in ICF both k-ω SST and LES are recommended. For the precise calculation of the motion of NMI smaller than 10 μm only LES model is appropriate.

  10. Effectiveness of Shot Peening In Suppressing Fatigue Cracking At Non-Metallic Inclusions In Udimet(Registered Trademark)720

    Science.gov (United States)

    Barrie, Robert L.; Gabb, Timothy P.; Telesman, Jack; Kantzos, Peter T.; Prescenzi, Anthony; Biles, T.; Bonacuse, P. J.

    2006-01-01

    The fatigue lives of modern powder metallurgy disk alloys can be reduced over an order of magnitude by cracking at inherent non-metallic inclusions. The objective of this work was to study the effectiveness of shot peening in suppressing LCF crack initiation and growth at surface nonmetallic inclusions. Inclusions were carefully introduced at elevated levels during powder metallurgy processing of the nickel-base disk superalloy Udimet 720. Multiple strain-controlled fatigue tests were then performed on machined specimens with and without shot peened test sections at 427 C and 650 C. The low cycle fatigue lives and failure initiation sites varied as functions of inclusion content, shot peening, and fatigue conditions. A large majority of the failures in as-machined specimens with the introduced inclusions occurred at cracks initiating from inclusions intersecting the specimen surface. These inclusions reduced fatigue life by up to 100X, when compared to lives of material without inclusions residing at specimen surface. Large inclusions produced the greatest reductions in life for tests at low strain ranges and high strain ratios. Shot peening improved life in many cases by reducing the most severe effects of inclusions.

  11. Effectiveness of Shot Peening in Suppressing Fatigue Cracking at Non-Metallic Inclusions in Udimet(trademark) 720

    Science.gov (United States)

    Barrie, Robert L.; Gabb, Timothy P.; Telesman, Jack; Kantzos, Peter T.; Prescenzi, Anthony; Biles, Tiffany; Bonacuse, Peter J.

    2005-01-01

    The fatigue lives of modern powder metallurgy disk alloys can be reduced by over an order of magnitude by surface cracking at inherent non-metallic inclusions. The objective of this work was to study the effectiveness of shot peening in suppressing LCF crack initiation and growth at surface nonmetallic inclusions. Inclusions were carefully introduced at elevated levels during powder metallurgy processing of the nickel-base disk superalloy Udimet 720. Multiple strain-controlled fatigue tests were then performed on machined specimens at 427 and 650 C in peened and unpeened conditions. Analyses were performed to compare the low cycle fatigue lives and failure initiation sites as a function of inclusion content, shot peening, and fatigue conditions. A large majority of the failures in as-machined specimens with introduced inclusions occurred at cracks initiating from inclusions intersecting the specimen surface. The inclusions could reduce fatigue life by up to 100X. Large inclusions had the greatest effect on life in tests at low strain ranges and high strain ratios. Shot peening can be used to improve life in these conditions by reducing the most severe effects of inclusions.

  12. The effect of non-metallic inclusions on the fracture toughness master curve in high copper reactor pressure vessel welds

    Science.gov (United States)

    Oh, Yong-Jun; Lee, Bong-Sang; Hong, Jun-Hwa

    2002-03-01

    The fracture toughness of two high copper reactor pressure vessel welds having low upper shelf energy was evaluated in accordance with the master curve method of ASTM E1921. The resultant data were correlated to the metallurgical factors involved in the brittle fracture initiation to provide a metallurgical-based understanding of the master curve. The tests were performed using pre-cracked Charpy V-notched specimens and the master curve was made with an average of T0 values determined at different temperatures. In all specimens, the cleavage fracture initiated at non-metallic inclusion ranging from 0.7 to 3.5 μm in diameter showing a scatter with the specimens and testing temperatures. Temperature dependency of the triggering particle size was not found. The fracture toughness ( KJC) was inversely proportional to the square root of the triggering inclusion diameter ( di) at respective temperatures. From this relationship, we determined median KJC values which correspond to the average value of triggering inclusion diameter of all tested specimens and defined them as a modified median KJC ( K'JC(med) ). The obtained K'JC(med) values showed quite smaller deviation from the master curve at different temperatures than the experimental median KJC values. This suggests that the master curve is on the premise of a constant dimension of key microstructural factor in a material regardless of the testing temperature. But the inclusion size at trigger point played an important role in the absolute position of the master curve with temperature and the consequent T0 value.

  13. The effect of non-metallic inclusions on the fracture toughness master curve in high copper reactor pressure vessel welds

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Yong-Jun E-mail: yjoh@kaeri.re.kr; Lee, Bong-Sang; Hong, Jun-Hwa

    2002-03-01

    The fracture toughness of two high copper reactor pressure vessel welds having low upper shelf energy was evaluated in accordance with the master curve method of ASTM E1921. The resultant data were correlated to the metallurgical factors involved in the brittle fracture initiation to provide a metallurgical-based understanding of the master curve. The tests were performed using pre-cracked Charpy V-notched specimens and the master curve was made with an average of T{sub 0} values determined at different temperatures. In all specimens, the cleavage fracture initiated at non-metallic inclusion ranging from 0.7 to 3.5 {mu}m in diameter showing a scatter with the specimens and testing temperatures. Temperature dependency of the triggering particle size was not found. The fracture toughness (K{sub J{sub C}}) was inversely proportional to the square root of the triggering inclusion diameter (d{sub i}) at respective temperatures. From this relationship, we determined median K{sub J{sub C}} values which correspond to the average value of triggering inclusion diameter of all tested specimens and defined them as a modified median K{sub J{sub C}} (K{sup '}{sub J{sub C}}{sub (med)}). The obtained K{sup '}{sub J{sub C}}{sub (med)} values showed quite smaller deviation from the master curve at different temperatures than the experimental median K{sub J{sub C}} values. This suggests that the master curve is on the premise of a constant dimension of key microstructural factor in a material regardless of the testing temperature. But the inclusion size at trigger point played an important role in the absolute position of the master curve with temperature and the consequent T{sub 0} value.

  14. Tunable electronic structures of germanium monochalcogenide nanosheets via light non-metallic atom functionalization: a first-principles study.

    Science.gov (United States)

    Ding, Yi; Wang, Yanli

    2016-08-17

    Germanium monochalcogenides, i.e. GeS and GeSe sheets, are isoelectronic analogues of phosphorene, which have been synthesized in recent experiments (P. Ramasamy et al., J. Mater. Chem. C, 2016, 4, 479). Utilizing first-principles calculations, we have investigated their tunable electronic and magnetic properties via light non-metallic atom (B, C, N, O, Si, P, S) functionalization. We find that on these GeS and GeSe sheets O and S adatoms prefer to locate at the top site above the Ge atom, while the other ones like to occupy the anion site, which push the original S/Se atom to the hollow site instead. O and S adatoms slightly affect the semiconducting behaviour of the doped systems, while B, C, N, Si, P ones will drastically modify their band structures and induce versatile spintronic properties. Through the supercell calculations, B and C adatoms are found to induce a bipolar semiconducting behaviour in the decorated systems, while the N/P adatom will cause a spin-gapless-semiconducting/nearly-half-metallic feature in them. The B/C/N/Si/P-substituted GeS/GeSe sheet can be formed by removing the hollow-site S/Se atom from the adatom-decorated structures, which exhibit an opposite semiconducting/metallic behaviour to their phosphorene counterparts. A general odd-even rule is proposed for this phenomenon, which shows that an odd (even) number of valence electron difference between the substitution and host atoms would cause a metallic (semiconducting) feature in the substituted systems. Our study demonstrates that atom functionalization is an efficient way to tailor the properties of GeS and GeSe nanosheets, which have adaptable electronic properties for potential applications in nanoelectronics and spintronics.

  15. Hydrothermal Preparation of Antibacterial Ag-containing TiO2 Film on a Low-modulus Titanium Alloy%低模量钛合金表面水热法制备含银二氧化钛抗菌薄膜

    Institute of Scientific and Technical Information of China (English)

    李红伟; 李雯; 付涛; 杨水云

    2015-01-01

    Objective To improve the antimicrobial properties of nearβ-type biomedical titanium alloy TLM (Ti-25Nb-3Zr-2Sn-3Mo) with low modulus. Methods TLM alloy was hydrothermally treated in silver nitrate solution at 200℃ with AgNO3 solution for 12 h and 24 h respectively to prepare antibacterial Ag-containing TiO2 film on its surface. The microstructure and status of the film were characterized by SEM, XRD and XPS. Using the TLM alloy hydrothermally treated in deionized water as the control, the hy-drophilicity of the film was compared, and the antimicrobial properties were studied using the inhibition zone method. Results SEM, XRD and XPS analyses showed that the film consisting of TiO2 nanocrystals was formed on the surface of TLM alloy after the hydrothermal treatment. X-ray photoelectron spectroscopy analysis illustrated that Ti and Nb on sample surface existed as TiO2 and Nb2 O5 respectively, and Ag was in the metallic form. Contact angle measurement indicated that the treated sample had good photo-induced hydrophilicity, and the contact angle decreased from 108. to below 10. after 30 min of UV irradiation. In the antibacterial test, obvious inhibition zones against E. coli and S. aureus were observed for the treated sample after 24 h culture, and the inhibi-tion zone was wider against S. aureus. Conclusion Through hydrothermal treatment at 200 ℃ with 10 mmol/L of AgNO3 solution, Ag-containing TiO2 film with antimicrobial properties could be synthesized. The hydrothermal method to prepare Ag-containing TiO2 film in medical titanium alloy has the merits of easy operation, low processing temperature, evident antibacterial effect, etc.%目的:提高医用低模量近β型TLM(Ti-25Nb-3Zr-2Sn-3Mo)钛合金的抗菌性能。方法在200℃条件下,在硝酸银溶液中对TLM合金分别进行12,24 h水热处理,在其表面制备含银TiO2抗菌薄膜。通过SEM,XRD,XPS等表征薄膜的微观结构及状态。以去离子水水热处理TLM合金作为参照,比

  16. 废弃电路板中非金属组分的回收利用%Recycling of non-metallic fractions from waste printed circuit boards

    Institute of Scientific and Technical Information of China (English)

    刘旸; 刘静欣; 江晓健; 郭学益

    2016-01-01

    废弃电路板是电子废弃物的重要组成部分。目前工业生产及工艺开发多针对极具经济回收价值的电路板金属组分。然而,占电路板质量分数70%的非金属组分却关注较少。文章分析了废弃电路板非金属组分的组成及其有害组分,其含有树脂及玻璃纤维等有价成分和溴、夹杂重金属等污染环境的物质,其回收利用对于资源循环利用及环境保护均有重要意义。非金属组分回收利用主要有物理处理和化学处理2种技术:物理处理技术主要将非金属组分用作结构材料填料、塑料改性剂和建筑材料改性剂;化学处理技术通过焚烧将非金属组分用作燃料和熔剂或通过热解回收或溶剂分解回收可将非金属组分转化为化工产品。这2种技术在非金属组分资源化利用上各有优势,都已有部分工业化应用。%Waste printed circuit boards (WPCBs) are important parts in the electronic waste. Nowadays, recov-ering metals from WPCBs are developed but non-metallic fractions which accounts for 70% of waste printed circuit boards have not been effectively utilized. The non-metallic fractions and hazards in waste printed cir-cuit boards were analyzed in this paper. The results show that resins and glass fiber in non-metallic fractions can be recycled and bromine and heavy metals could pollute environment. Recovering non-metallic fractions are important to recycling and environment, which can be divided into physical recycling technology and chemical recycling technology, with the formal using non-metallic fractions as the filler materials, plastic modifier or building material modifiers, and the latter using non-metallic fractions as the fuel and smelting flux through incineration or convert non-metallic fractions into chemical products through pyrolysis or solvent decomposition. Both technologies have their own advantages in resource utilization of non-metallic fractions, and partly

  17. The Influence of Technological Parameters of X70 Stainless Steel Ladle Refining on the Residual Content of Non-Metallic Inclusions

    Directory of Open Access Journals (Sweden)

    Babanin A.

    2015-09-01

    Full Text Available It is demonstrated that during secondary refining at the ladle furnace the carbon content of steel and the residence time of the metal in the ladle exert a significant impact on the residual content of non-metallic inclusions (NMI in steel. Mathematical calculations showed that the dynamic forces have minor effect on the motion of small sized NMI, making it difficult to penetrate deep into the slag.

  18. Study of the physicochemical effects on the separation of the non-metallic fraction from printed circuit boards by inverse flotation.

    Science.gov (United States)

    Flores-Campos, R; Estrada-Ruiz, R H; Velarde-Sánchez, E J

    2017-09-06

    Recycling printed circuit boards using green technology is increasingly important due to the metals these contain and the environmental care that must be taken when separating the different materials. Inverse flotation is a process that can be considered a Green Technology, which separates metallic from non-metallic fractions. The degree of separation depends on how much material is adhered to air bubbles. The contact angle measurement allows to determine, in an easy way, whether the flotation process will occur or not and thus establish a material as hydrophobic or not. With the material directly obtained from the milling process, it was found that the contact angle of the non-metallic fraction-liquid-air system increases as temperature increases. In the same way, the increments in concentration of frother in the liquid increase the contact angle of the non-metallic fraction-liquid-air system. 10ppm of Methyl Isobutyl Carbinol provides the highest contact angle as well as the highest material charging in the bubble. Copyright © 2017. Published by Elsevier Ltd.

  19. The Diesel Exhaust in Miners Study: IV. Estimating historical exposures to diesel exhaust in underground non-metal mining facilities.

    Science.gov (United States)

    Vermeulen, Roel; Coble, Joseph B; Lubin, Jay H; Portengen, Lützen; Blair, Aaron; Attfield, Michael D; Silverman, Debra T; Stewart, Patricia A

    2010-10-01

    We developed quantitative estimates of historical exposures to respirable elemental carbon (REC) for an epidemiologic study of mortality, including lung cancer, among diesel-exposed miners at eight non-metal mining facilities [the Diesel Exhaust in Miners Study (DEMS)]. Because there were no historical measurements of diesel exhaust (DE), historical REC (a component of DE) levels were estimated based on REC data from monitoring surveys conducted in 1998-2001 as part of the DEMS investigation. These values were adjusted for underground workers by carbon monoxide (CO) concentration trends in the mines derived from models of historical CO (another DE component) measurements and DE determinants such as engine horsepower (HP; 1 HP = 0.746 kW) and mine ventilation. CO was chosen to estimate historical changes because it was the most frequently measured DE component in our study facilities and it was found to correlate with REC exposure. Databases were constructed by facility and year with air sampling data and with information on the total rate of airflow exhausted from the underground operations in cubic feet per minute (CFM) (1 CFM = 0.0283 m³ min⁻¹), HP of the diesel equipment in use (ADJ HP), and other possible determinants. The ADJ HP purchased after 1990 (ADJ HP₁₉₉₀(+)) was also included to account for lower emissions from newer, cleaner engines. Facility-specific CO levels, relative to those in the DEMS survey year for each year back to the start of dieselization (1947-1967 depending on facility), were predicted based on models of observed CO concentrations and log-transformed (Ln) ADJ HP/CFM and Ln(ADJ HP₁₉₉₀(+)). The resulting temporal trends in relative CO levels were then multiplied by facility/department/job-specific REC estimates derived from the DEMS surveys personal measurements to obtain historical facility/department/job/year-specific REC exposure estimates. The facility-specific temporal trends of CO levels (and thus the REC

  20. Effect of inhomogeneous distribution of non-metallic inclusions on crack path deflection in G42CrMo4 steel at different loading rates

    Directory of Open Access Journals (Sweden)

    S. Henschel

    2015-10-01

    Full Text Available An inhomogeneous distribution of non-metallic inclusions can result from the steel casting process. The aim of the present study was to investigate the damaging effect of an inhomogeneous distribution of nonmetallic inclusions on the crack extension behavior. To this end, the fracture toughness behavior in terms of quasi-static J-a curves was determined at room temperature. Additionally, dynamic fracture mechanics tests in an instrumented Charpy impact-testing machine were performed. The fracture surface of fracture mechanics specimens was analyzed by means of scanning electron microscopy. It was shown that an inhomogeneous distribution significantly affected the path and, therefore, the plane of crack growth. Especially clusters of non-metallic inclusions with a size of up to 200 μm exhibited a very low crack growth resistance. Due to the damaging effect of the clusters, the growing crack was strongly deflected towards the cluster. Furthermore, crack tip blunting was completely inhibited when inclusions were located at the fatigue precrack tip. Due to the large size of the non-metallic inclusion clusters, the height difference introduced by crack path deflection was significantly larger than the stretch zone height due to the crack tip blunting. However, the crack path deflection introduced by a cluster was not associated with a toughness increasing mechanism. The e dynamic loading ( 1 0.5 5 s MPam 10   K did not result in a transition from ductile fracture to brittle fracture. However, the crack growth resistance decreased with increased loading rate. This was attributed to the higher portion of relatively flat regions where the dimples were less distinct.

  1. Effect Of Non-metal Elements (C, N, S) As Anionic Dopants On Electronic Structure Of Tio2-Anatase By Density-Functional Theory Approach

    OpenAIRE

    Hari Sutrisno

    2016-01-01

    This article is a theoritical approach to calculate the electronic structure of undoped- and non-metal anions doped-TiO2-anatase. The objective of the research is to calculate abinitio the band structure and the density of states (DOS) of undoped-, C-, N-, and S-doped TiO2-anatase. Kohn-Sham equations are performed with the density functional theory (DFT) using the local density approximation (LDA) for exchange-correlation functional. The first-principle calculations were done using supercell...

  2. Study of the nature of non-metallic inclusions in samples of aluminum and silicon killed low carbon steels, collected in the refining treatment and continuous casting stages

    Directory of Open Access Journals (Sweden)

    José Carlos Santos Pires

    2004-12-01

    Full Text Available The amount, distribution, size and chemical composition of non-metallic inclusions have a direct influence on steel properties. By controlling size and chemical composition of these inclusions, it is possible to get a product with good quality. The identification of the nature and the control of inclusion formation are very important for steel cleanness. The behavior of these inclusions is predictable, in some extent, by the determination of the chemical composition of non-metallic phases that form such inclusions. With the objective of studying the chemical composition, the size and the distribution of such inclusions, samples of aluminum and silicon killed low carbon steels were collected in a national steel industry in the secondary refining and continuous casting stages. These samples were analyzed in the scanning electron microscope (SEM coupled to an energy dispersive analysis system (EDS. From the results, it was possible to evaluate the nature of inclusions and to analyze the effectiveness of the refining process in the reduction of the number and area fraction of the inclusions. It was also possible to verify that the inclusions that remained after treatment, are less damage both to the steel properties as to the continuous casting process (clogging of the submerged valve.

  3. Strength and deformability of compressed concrete elements with various types of non-metallic fiber and rods reinforcement under static loading

    Science.gov (United States)

    Nevskii, A. V.; Baldin, I. V.; Kudyakov, K. L.

    2015-01-01

    Adoption of modern building materials based on non-metallic fibers and their application in concrete structures represent one of the important issues in construction industry. This paper presents results of investigation of several types of raw materials selected: basalt fiber, carbon fiber and composite fiber rods based on glass and carbon. Preliminary testing has shown the possibility of raw materials to be effectively used in compressed concrete elements. Experimental program to define strength and deformability of compressed concrete elements with non-metallic fiber reinforcement and rod composite reinforcement included design, manufacture and testing of several types of concrete samples with different types of fiber and longitudinal rod reinforcement. The samples were tested under compressive static load. The results demonstrated that fiber reinforcement of concrete allows increasing carrying capacity of compressed concrete elements and reducing their deformability. Using composite longitudinal reinforcement instead of steel longitudinal reinforcement in compressed concrete elements insignificantly influences bearing capacity. Combined use of composite rod reinforcement and fiber reinforcement in compressed concrete elements enables to achieve maximum strength and minimum deformability.

  4. Imaging of metals, metalloids, and non-metals by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) in biological tissues.

    Science.gov (United States)

    Becker, J Sabine; Becker, J Susanne

    2010-01-01

    The determination of the localization and distribution of essential and beneficial metals (e.g., Cu, Fe, Zn, Mn, Co, Ti, Al, Ca, K, Na, Cr and others), toxic metals (like Cd, Pb, Hg, U), metalloids (e.g., As, Se, Sb), and non-metals (such as C, S, P, Cl, I) in biological tissues is a challenging task for life science studies. Over the past few years, the development and application of mass spectrometric imaging (MSI) techniques for elements has been rapidly growing in the life sciences in order to investigate the uptake and the transport of both essential and toxic metals in plant and animal sections. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is a very sensitive and efficient trace, surface, and isotopic analytical technique for biological samples. LA-ICP-MS is increasingly utilized as an elemental mass spectrometric technique using double-focusing sector field (LA-ICP-SFMS) or quadrupole mass spectrometers (LA-ICP-QMS) to produce images of detailed regionally specific element distributions in thin biological tissue sections. Nowadays, MSI studies focus on brain research for studying neurodegenerative diseases such as Alzheimer's or Parkinson's, stroke, or tumor growth, or for the imaging of cancer biomarkers in tissue sections.The combination of the mass spectrometry imaging of metals by LA-ICP-MS with proteomics using biomolecular mass spectrometry (such as MALDI-MS or ESI-MS) to identify metal-containing proteins has become an important strategy in the life sciences. Besides the quantitative imaging of metals, non-metals and metalloids in biological tissues, LA-ICP-MS has been utilized for imaging metal-containing proteins in a 2D gel after electrophoretic separation of proteins. Recent progress in applying LA-ICP-MS in life science studies will be reviewed including the imaging of thin slices of biological tissue and applications in proteome analysis in combination with MALDI/ESI-MS to analyze metal-containing proteins.

  5. Analysis of industry development of building materials and ore mining and dressing of non-metallic minerals%2011年建材及非金属矿采选业行业发展分析

    Institute of Scientific and Technical Information of China (English)

    何军生

    2012-01-01

    In 2011, the growth of building materials production remained stable, industrial structure contiuned to optimise, economic porfits improved. In this paper, the author firstly discusses economic operation of building materials and ore mining and dressing of non-metallic minerals in 2011, to adjust the industrial structure of building materials and ore mining and dressing of non-metallic minerals to impove the quality of the economic operation, predicts the development trend of industry of building materials and ore mining and dressing of non-metallic minerals in 2012. At last, the author puts forward to policy suggestions which accelerate industry deleopment of the building materials and ore mining and dressing of non-metallic minerals%2011年建材工业生产增长速度保持平稳,产业结构继续优化,经济效益提高.本文首先讨论了2011年建材工业经济及非金属矿采选行业经济运行情况,做到调整建材及非金属矿选行业产业结构,提高经济运行质量,预测了2012年建材及非金属矿选行业未来发展趋势,最后提出促进建材及非金属矿选行业发展的政策建议.

  6. Mechanical properties of low modulus beta titanium alloys designed from the electronic approach.

    Science.gov (United States)

    Laheurte, P; Prima, F; Eberhardt, A; Gloriant, T; Wary, M; Patoor, E

    2010-11-01

    Titanium alloys dedicated to biomedical applications may display both clinical and mechanical biocompatibility. Based on nontoxic elements such as Ti, Zr, Nb, Ta, they should combine high mechanical resistance with a low elastic modulus close to the bone elasticity (E=20 GPa) to significantly improve bone remodelling and osseointegration processes. These elastic properties can be reached using both lowering of the intrinsic modulus by specific chemical alloying and superelasticity effects associated with a stress-induced phase transformation from the BCC metastable beta phase to the orthorhombic alpha(″) martensite. It is shown that the stability of the beta phase can be triggered using a chemical formulation strategy based on the electronic design method initially developed by Morinaga. This method is based on the calculation of two electronic parameters respectively called the bond order (B(o)) and the d orbital level (M(d)) for each alloy. By this method, two titanium alloys with various tantalum contents, Ti-29Nb-11Ta-5Zr and Ti-29Nb-6Ta-5Zr (wt%) were prepared. In this paper, the effect of the tantalum content on the elastic modulus/yield strength balance has been investigated and discussed regarding the deformation modes. The martensitic transformation beta-->alpha(″) has been observed on Ti-29Nb-6Ta-5Zr in contrast to Ti-29Nb-11Ta-5Zr highlighting the chemical influence of the Ta element on the initial beta phase stability. A formulation strategy is discussed regarding the as-mentioned electronic parameters. Respective influence of cold rolling and flash thermal treatments (in the isothermal omega phase precipitation domain) on the tensile properties has been investigated.

  7. Origin of high strength, low modulus superelasticity in nanowire-shape memory alloy composites

    Science.gov (United States)

    Zhang, Xudong; Zong, Hongxiang; Cui, Lishan; Fan, Xueling; Ding, Xiangdong; Sun, Jun

    2017-04-01

    An open question is the underlying mechanisms for a recent discovered nanocomposite, which composed of shape memory alloy (SMA) matrix with embedded metallic nanowires (NWs), demonstrating novel mechanical properties, such as large quasi-linear elastic strain, low Young’s modulus and high yield strength. We use finite element simulations to investigate the interplay between the superelasticity of SMA matrix and the elastic-plastic deformation of embedded NWs. Our results show that stress transfer plays a dominated role in determining the quasi-linear behavior of the nanocomposite. The corresponding microstructure evolution indicate that the transfer is due to the coupling between plastic deformation within the NWs and martensitic transformation in the matrix, i.e., the martensitic transformation of the SMA matrix promotes local plastic deformation nearby, and the high plastic strain region of NWs retains considerable martensite in the surrounding SMA matrix, thus facilitating continues martensitic transformation in subsequent loading. Based on these findings, we propose a general criterion for achieving quasi-linear elasticity.

  8. Triboelectric separation technology for removing inorganics from non-metallic fraction of waste printed circuit boards: Influence of size fraction and process optimization.

    Science.gov (United States)

    Zhang, Guangwen; Wang, Haifeng; He, Yaqun; Yang, Xing; Peng, Zhen; Zhang, Tao; Wang, Shuai

    2017-02-01

    Removing inorganics from non-metallic fraction (NMF) of waste printed circuit boards (WPCBs) is an effective mean to improve its usability. The effect of size fraction on the triboelectric separation of NMF of WPCBs was investigated in a lab triboelectric separation system and the separation process was optimized in this paper. The elements distribution in raw NMF collected from typical WPCBs recycling plant and each size fraction obtained by sieving were analyzed by X-ray fluorescence (XRF). The results show that the main inorganic elements in NMF are P, Ba, Mn, Sb, Ti, Pb, Zn, Sn, Mg, Fe, Ca, Cu, Al and Si. The inorganic content of each size fraction increased with the size decreasing. The metal elements are mainly distributed in -0.2mm size fraction, and concentrated in middle product of triboelectric separation. The loss on ignition (LOI) of positive product and negative product is higher than that of the middle product for the -0.355mm size fraction, while the LOI presents gradually increasing trend from negative to positive plate for the +0.355mm size fraction. Based on the separation results and mineralogical characterizations of each size fraction of NMF, the pretreatment process including several mineral processing operations was added before triboelectric separation and better separation result was obtained. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Construction of stable Ta3N5/g-C3N4 metal/non-metal nitride hybrids with enhanced visible-light photocatalysis

    Science.gov (United States)

    Jiang, Yinhua; Liu, Peipei; Chen, YeCheng; Zhou, Zhengzhong; Yang, Haijian; Hong, Yuanzhi; Li, Fan; Ni, Liang; Yan, Yongsheng; Gregory, Duncan H.

    2017-01-01

    In this paper, a novel Ta3N5/g-C3N4 metal/non-metal nitride hybrid was successfully synthesized by a facile impregnation method. The photocatalytic activity of Ta3N5/g-C3N4 hybrid nitrides was evaluated by the degradation of organic dye rhodamine B (RhB) under visible light irradiation, and the result indicated that all Ta3N5/g-C3N4 samples exhibited distinctly enhanced photocatalytic activities for the degradation of RhB than pure g-C3N4. The optimal Ta3N5/g-C3N4 composite sample, with Ta3N5 mass ratio of 2%, demonstrated the highest photocatalytic activity, and its degradation rate constant was 2.71 times as high as that of pure g-C3N4. The enhanced photocatalytic activity of this Ta3N5/g-C3N4 metal/metal-free nitride was predominantly attributed to the synergistic effect which increased visible-light absorption and facilitated the efficient separation of photoinduced electrons and holes. The Ta3N5/g-C3N4 hybrid nitride exhibited excellent photostability and reusability. The possible mechanism for improved photocatalytic performance was proposed. Overall, this work may provide a facile way to synthesize the highly efficient metal/metal-free hybrid nitride photocatalysts with promising applications in environmental purification and energy conversion.

  10. Free-energy calculations for semi-flexible macromolecules: Applications to DNA knotting and looping

    Energy Technology Data Exchange (ETDEWEB)

    Giovan, Stefan M. [Department of Molecular and Cell Biology, University of Texas at Dallas, Richardson, Texas 75083 (United States); Scharein, Robert G. [Hypnagogic Software, Vancouver, British Columbia V6K 1V6 (Canada); Hanke, Andreas [Department of Physics and Astronomy, University of Texas at Brownsville, Brownsville, Texas 78520 (United States); Levene, Stephen D., E-mail: sdlevene@utdallas.edu [Department of Molecular and Cell Biology, University of Texas at Dallas, Richardson, Texas 75083 (United States); Department of Bioengineering, University of Texas at Dallas, Richardson, Texas 75083 (United States); Department of Physics, University of Texas at Dallas, Richardson, Texas 75083 (United States)

    2014-11-07

    We present a method to obtain numerically accurate values of configurational free energies of semiflexible macromolecular systems, based on the technique of thermodynamic integration combined with normal-mode analysis of a reference system subject to harmonic constraints. Compared with previous free-energy calculations that depend on a reference state, our approach introduces two innovations, namely, the use of internal coordinates to constrain the reference states and the ability to freely select these reference states. As a consequence, it is possible to explore systems that undergo substantially larger fluctuations than those considered in previous calculations, including semiflexible biopolymers having arbitrary ratios of contour length L to persistence length P. To validate the method, high accuracy is demonstrated for free energies of prime DNA knots with L/P = 20 and L/P = 40, corresponding to DNA lengths of 3000 and 6000 base pairs, respectively. We then apply the method to study the free-energy landscape for a model of a synaptic nucleoprotein complex containing a pair of looped domains, revealing a bifurcation in the location of optimal synapse (crossover) sites. This transition is relevant to target-site selection by DNA-binding proteins that occupy multiple DNA sites separated by large linear distances along the genome, a problem that arises naturally in gene regulation, DNA recombination, and the action of type-II topoisomerases.

  11. Semi-flexible gas-insulated transmission line using sandwiched discs for intermittent flexing joints

    Energy Technology Data Exchange (ETDEWEB)

    Kommineni, Prasad R. (Westboro, MA)

    1983-02-15

    A gas-insulated transmission line includes an outer sheath, an inner conductor, an insulating gas electrically insulating the inner conductor from the outer sheath, and insulating supports insulatably supporting the inner conductor within the outer sheath. The inner conductor is provided with flexibility by the use of main conductor sections which are joined together through a conductor hub section and flexible flexing elements. Stress shields are provided to control the electric field at the locations of the conductor hub sections where the insulating supports are contacting the inner conductor. The flexing elements are formed by sandwiching together, by fusing, a pair of thin hollow discs which are fixedly secured to both the main conductor sections and the conductor hub section.

  12. Semi-flexible gas-insulated transmission line using sandwiched discs for intermittent flexing joints

    Energy Technology Data Exchange (ETDEWEB)

    Kommineni, P.R.

    1983-02-15

    A gas-insulated transmission line includes an outer sheath, an inner conductor, an insulating gas electrically insulating the inner conductor from the outer sheath, and insulating supports insulatably supporting the inner conductor within the outer sheath. The inner conductor is provided with flexibility by the use of main conductor sections which are joined together through a conductor hub section and flexible flexing elements. Stress shields are provided to control the electric field at the locations of the conductor hub sections where the insulating supports are contacting the inner conductor. The flexing elements are formed by sandwiching together, by fusing, a pair of thin hollow discs which are fixedly secured to both the main conductor sections and the conductor hub section. 4 figs.

  13. Weak interlayers in flexible and semi-flexible road pavements: Part 1

    CSIR Research Space (South Africa)

    Netterberg, F

    2012-04-01

    Full Text Available African Institution of Civil Engineering ? Volume 54 Number 1 April 201232 Photo 1 Pumping loose material from a cemented base/subbase pavement at Hornsnek, West of Pretoria during 1985 TECHNICAL PAPER JOURNAL OF THE SOUTH AFRICAN INSTITUTION...@csir.co.za Note The 27 photos and 12 ?gures are numbered continuously throughout Part?1 and Part 2 of this two-part set of papers. However, the references and equation numbers are speci?c to each part. Key words: weak layers, interlayers, detection, pavement...

  14. Conformations, Transverse Fluctuations and Crossover Dynamics of a Semi-Flexible Chain in Two Dimensions

    CERN Document Server

    Huang, Aiqun; Binder, Kurt

    2014-01-01

    We present a unified scaling theory for the dynamics of monomers of a semiflexible chain under good solvent condition in the free draining limit. We consider both the cases where the contour length $L$ is comparable to the persistence length $\\ell_p$ and the case $L\\gg \\ell_p$. Our theory captures the early time monomer dynamics of a stiff chain characterized by $t^{3/4}$ dependence for the mean square displacement(MSD) of the monomers, but predicts a first crossover to the Rouse regime of $t^{2\

  15. Non-Metallic Biomaterials for Tooth Repair and Replacement. By Pekka Vallittu, Woodhead Publishing, 2013; 406 pages. Price £145.00/US$245.00/€175.00 ISBN 978-0-85709-244-1

    Directory of Open Access Journals (Sweden)

    Shu-Kun Lin

    2013-01-01

    Full Text Available 1. Discusses the properties of enamel and dentin and their role in adhesive dental restoration;2. Chapters also examine the wear properties of dental ceramics, glasses and bioactive glass ceramics for tooth repair and replacement;3. Dental composites and antibacterial restorative materials are also considered;4. Provides a concise overview of non-metallic biomaterials for dental clinicians, materials scientists and academic researchers alike.As the demand for healthy, attractive teeth increases, the methods and materials employed in restorative dentistry have become progressively more advanced. Non-metallic biomaterials for tooth repair and replacement focuses on the use of biomaterials for a range of applications in tooth repair and, in particular, dental restoration.

  16. 钢中非金属夹杂物的形成及评判浅析%ANALYSIS OF FORMATION AND EVALUATION OF NON-METALLIC INCLUSIONS IN STEEL

    Institute of Scientific and Technical Information of China (English)

    瞿国鸿; 何开文; 张全新

    2014-01-01

    本文阐述了钢中非金属夹杂物的形成、分类及来源,以及非金属夹杂物数量、尺寸对钢材性能的影响,对评判非金属夹杂物的国家标准GB/T 10561新旧两个版本即2005版和1989版进行比较,分析了氮化物等沉淀相的特性及其对钢材的强化作用,阐明了2005版标准中关于将氮化物、碳化物、碳氮化合物、硼化物定性描述为沉淀相而不作为非金属夹杂物的评判是适宜的。%This paper describes the formation , classification and source of non -metallic inclusions in steel , and the influence of their quantity and size on the performance of steels .It compares the commons and differences between the new National Standard GB /T10561 2005 version with the old 1989 version for evaluating non-metallic inclusions , and analyzes the characteristics of the precipitated phase such as the nitride and the strengthening effect to the steel , and explains that it is appropriate to evaluate ni-trides, carbides, hydrocarbons and boride as precipitated phase not as non -metallic inclusions.

  17. Review on Insensitive Non-metallic Energetic Ionic Compounds of Tetrazolate Anions%不敏感四唑非金属含能离子化合物的研究进展

    Institute of Scientific and Technical Information of China (English)

    毕福强; 樊学忠; 许诚; 王伯周; 郑亚峰; 葛忠学; 刘庆

    2012-01-01

    四唑非金属含能离子化合物是近年来逐渐发展起来的一类新型不敏感含能材料.综述了以氨基四唑、硝基四唑、硝氨基四唑、偶氮四唑和呋咱取代四唑为阴离子的不敏感非金属含能离子化合物的研究进展,结果表明,5位连有硝基和硝氨基等传统含能基团的四唑离子化合物的感度普遍较高,而以氨基四唑、偶氮四唑和4-氨基-3-(四唑基)呋咱为阴离子的含能化合物有望在不敏感含能材料领域得到广泛应用,并进而提出了不敏感四唑非金属含能离子化合物研究的发展方向.%Non-metallic energetic ionic compounds of tetrazolate anion are a kind of insensitive energetic materials. The progresses in the insensitive non-metallic energetic salts of aminotetrazolate, nitrotetrazolate, nitraminotetrazolate, azotetrazolate and furazan fuctionalized tetrazolate anions were reviewed in detail. It is found that most of ionic compounds based on tetrazolate anions which contain traditional energetic functionalities upon the carbon of positon 5 such as nitro and nitrimino functionalities, show high sensitivities, while the sensitivities of ionic compounds based on 5-aminotetrazolate, 5, 5'-azotetrazolate and 5-(4-aminofurazan-3-yl)tetrazolate are so low that they can be used as insensitive energetic materials. Furthermore, new trends in research of insensitive non-metallic energetic ionic compounds of tetrazolate anion were proposed.

  18. An innovate method to recycle non-metallic materials from waste printed circuit board.%废线路板非金属物料再生利用新型工艺研究

    Institute of Scientific and Technical Information of China (English)

    段华波; 李金惠; 王斯婷

    2012-01-01

    The reuse of non-metallic material separated from PWBs residues before and after thermo-shocked pretreatment was investigated. With the blending of various additives from silane coupling agents, lubricant agents, anti-oxidizing agents to processing modifier, the non-metallic material could be filled to produce polymeric composite materials subjected to the injection and molding processes. Said method was also appropriate to thermo-shocked non-metallic material. The mechanical property was qualified by compared with the standard limit of related composite materials. The maximum amount of recyclate that could be added to a composite board was 30% of weight, with the additive agents of: silane coupling agents (1%), lubricant agents (1%), anti-oxidizing agents (1%) and processing modifier (5%).%以加热改性处理前后的废线路板非金属物料为对象,对其再生利用工艺进行了研究.通过添加硅烷偶联剂、润滑剂、抗氧化剂和改性剂等助剂改性共混,基于挤出注塑成型工艺过程,可制备废线路板非金属物料填充增强聚丙烯复合板材,该工艺同时可适合一定温度条件下加热改性处理后的非金属物料,其主要力学性能符合相关制品产品质量标准.确定的优化参数为:非金属物料添加质量分数30%,添加助剂包括硅烷偶联剂(1%)、润滑剂(1%)、抗氧化剂(1%)和改性剂(5%).

  19. Development of Non-metal Material Query System for Satellite-borne Radar Based on .NET Framework%基于.NET框架的星载雷达非金属材料查询系统开发

    Institute of Scientific and Technical Information of China (English)

    程丹; 欧屹

    2011-01-01

    Based on .NET framework,the non-metal material query system for satellite-borne radar was developed in the environment of Visual Studio 2005.The web pages were written by ASP.NET while the database was developed using Oracle9i.This system realizes query of non-metal material data for satellite-borne radar in enterprise LAN.It can also carry out data maintenance via administrator account.This system effectively realizes knowledge sharing,and also provides a good cooperative working environment for the enterprise.%基于.NET框架,在Visual Studio 2005环境中开发了星载雷达非金属材料查询系统,前台Web页面和后台数据库分别采用ASP.NET和Oracle9i进行开发。该系统能够在企业局域网范围内实现对星载雷达非金属材料相关信息的查询,且通过登录管理员帐户,可以实现对材料信息的数据维护。该系统有效实现了知识共享,为企业提供了理想的协同工作环境。

  20. Rare earth metals influence on morphology of non-metallic inclusions and mechanism of GP240GH and G17CrMo5-5cast steel cracking

    Directory of Open Access Journals (Sweden)

    M. Gajewski

    2009-10-01

    Full Text Available This paper presents results of research carried out in order to specify the influence of the rare earth metals on the morphology of the occuring non-metallic inclusions as well as on the cracking mechanism of GP240GH cast carbon steel and G17CrMo5-5 (0.18%C, 1.2%Cr, 0.53%Mo high temperature cast steel. The tests have been performed on successive industrial melts adding rare earth metals to the ladle during tapping of heat melt from the furnace. It was found that ball-shaped non-metalic inclusions occuring as a result of the rare earth metals influence are heterogenic and they significantly influence the cracking mechanism of Charpy specimens and the impact strength. The morphology of the specimens fracture surface has been substantially changed as a result of the rare earth metals modification. The impact strength of the tested cast carbon steel increased from 100 J/cm2 to ca 155 J/cm2, and the high-temperature cast steel from 30 J/cm2 to ca 100 J/cm2.

  1. 超低氧齿轮钢非金属夹杂物控制热力学计算及应用%Thermodynamic Calculation and Application of Non-Metallic Inclusions for Ultra-Low-Oxygen Gear Steel

    Institute of Scientific and Technical Information of China (English)

    陈天明

    2011-01-01

    利用热力学软件计算了齿轮钢氧含量与夹杂物成分的关系、夹杂物转变条件.结果表明,超低氧20CrMoH钢中具有较高塑性的非金属夹杂物成分(质量分数)为:SiO2 0~10%,Al2O3 22%~55%,CaO 42%~60%,MgO 5%~10%,与之平衡的时钢液中铝质量分数在0.020%左右,钙质量分数大于0.7×10-6,氧质量分数在0.000 5%左右.选择组成:w(CaO)>40%,w(Al2O3)≤37%,w(MgO)为10%,(w(CaO)+w(MgO))/w(SiO2)为10,SiO2含量尽量低的渣系,钢中Al2O3、MgO·Al2O3夹杂物可转变为低熔点的钙铝酸盐.%Interrelations between oxygen content of gear steel and non-metallic inclusions, and transformations conditions for non-metallic inclusions were calculated using the thermodynamic calculation software Factsage. It is found that the components of non-metallic inclusions with higher plasticity in ultra-low-oxygen gear steel should be composed by SiO2 0-10%, Al2O3 22%-55%, CaO 42%-60%, and MgO 5%-10%, aluminum content would be about 0.020%, calcium content would be more than 0.7 × 10-6 , and oxygen content would be about 0.0005 % in molten steel when the reaction between the inclusion and liquid steel arrived in equilibrium. If the compositions of fining slag with w(CaO)>40%, w(Al2O3 )≤37% ,w(MgO) = 10% ,(w(CaO) +w(MgO))/w(SiO2 ) = 10, and SiO2 content as low as possible were selected, Al2O3 and MgO · Al2O3 in molten steel can transform into calcium aluminates with low melting point.

  2. Analysis of the treatment of plastic from electrical and electronic waste in the Republic of Serbia and the testing of the recycling potential of non-metallic fractions of printed circuit boards

    Directory of Open Access Journals (Sweden)

    Vučinić Aleksandra S.

    2017-01-01

    Full Text Available This paper presents the analysis of the quantity of plastic and waste printed circuit boards obtained after the mechanical treatment of electrical and electronic waste (E-waste in the Republic of Serbia, as well as the recycling of non-metallic fractions of waste printed circuit boards. The aim is to analyze the obtained recycled material and recommendation for possible application of recyclables. The data on the quantities and treatment of plastics and printed circuit boards obtained after the mechanical treatment of WEEE, were gained through questionnaires sent to the operators who treat this type of waste. The results of the questionnaire analysis showed that in 2014 the dismantling of E-waste isolated 1,870.95 t of plastic and 499.85 t of printed circuit boards. In the Republic of Serbia, E-waste recycling is performed exclusively by using mechanical methods. Mechanical methods consist of primary crushing and separation of the materials which have a utility value as secondary raw materials, from the components and materials that have hazardous properties. Respect to that, the recycling of printed circuit boards using some of the metallurgical processes with the aim of extracting copper, precious metals and non-metallic fraction is completely absent, and the circuit boards are exported as a whole. Given the number of printed circuit boards obtained by E-waste dismantling, and the fact that from an economic point of view, hydrometallurgical methods are very suitable technological solutions in the case of a smaller capacity, there is a possibility for establishing the facilities in the Republic of Serbia for the hydrometallurgical treatment that could be used for metals extraction, and non-metallic fractions, which also have their own value. Printed circuit boards granulate obtained after the mechanical pretreatment and the selective removal of metals by hydrometallurgical processes was used for the testing of the recycling potential

  3. A β-type TiNbZr alloy with low modulus and high strength for biomedical applications

    Directory of Open Access Journals (Sweden)

    Qingkun Meng

    2014-04-01

    Full Text Available The effect of thermo-mechanical treatment on the mechanical properties of a novel β-type Ti–36Nb–5Zr (wt% alloy has been investigated. The solution treated alloy consists of β and α″ phases and exhibits a two-stage yielding with a low yield stress (around 100 MPa. After cold rolling at a reduction of 87.5% and subsequent annealing treatment at 698 K for 25 min, a fine microstructure with nanosized α precipitates distributed in small β grains as well as high density of dislocations was obtained to achieve a yield strength of 720 MPa and a ultimate tensile strength of 860 MPa. In spite of the formation of α precipitates, the β-stabilizers are not enriched in the parent β matrix due to the short duration and low temperature of the thermal treatment, resulting in a low chemical stability of β phase. The low stability of β phase and the small volume fraction of α precipitates produce a low Young׳s modulus of 48 GPa. Such an excellent combination of low elastic modulus and high strength in mechanical properties indicates great potential for biomedical applications.

  4. A β-type TiNbZr alloy with low modulus and high strength for biomedical applications

    OpenAIRE

    Qingkun Meng; Shun Guo; Qing Liu; Liang Hu; Xinqing Zhao

    2014-01-01

    The effect of thermo-mechanical treatment on the mechanical properties of a novel β-type Ti–36Nb–5Zr (wt%) alloy has been investigated. The solution treated alloy consists of β and α″ phases and exhibits a two-stage yielding with a low yield stress (around 100 MPa). After cold rolling at a reduction of 87.5% and subsequent annealing treatment at 698 K for 25 min, a fine microstructure with nanosized α precipitates distributed in small β grains as well as high density of dislocations was obtai...

  5. Aβ-type TiNbZr alloy with low modulus and high strength for biomedical applications

    Institute of Scientific and Technical Information of China (English)

    Qingkun Meng; Shun Guo; Qing Liu; Liang Hu; Xinqing Zhao

    2014-01-01

    The effect of thermo-mechanical treatment on the mechanical properties of a novelβ-type Ti-36Nb-5Zr (wt%) alloy has been investigated. The solution treated alloy consists of β and α″phases and exhibits a two-stage yielding with a low yield stress (around 100 MPa). After cold rolling at a reduction of 87.5% and subsequent annealing treatment at 698 K for 25 min, a fine microstructure with nanosized α precipitates distributed in smallβgrains as well as high density of dislocations was obtained to achieve a yield strength of 720 MPa and a ultimate tensile strength of 860 MPa. In spite of the formation ofαprecipitates, theβ-stabilizers are not enriched in the parentβmatrix due to the short duration and low temperature of the thermal treatment, resulting in a low chemical stability ofβphase. The low stability ofβphase and the small volume fraction ofαprecipitates produce a low Young's modulus of 48 GPa. Such an excellent combination of low elastic modulus and high strength in mechanical properties indicates great potential for biomedical applications.

  6. Crack nucleation using combined crystal plasticity modelling, high-resolution digital image correlation and high-resolution electron backscatter diffraction in a superalloy containing non-metallic inclusions under fatigue.

    Science.gov (United States)

    Zhang, Tiantian; Jiang, Jun; Britton, Ben; Shollock, Barbara; Dunne, Fionn

    2016-05-01

    A crystal plasticity finite-element model, which explicitly and directly represents the complex microstructures of a non-metallic agglomerate inclusion within polycrystal nickel alloy, has been developed to study the mechanistic basis of fatigue crack nucleation. The methodology is to use the crystal plasticity model in conjunction with direct measurement at the microscale using high (angular) resolution-electron backscatter diffraction (HR-EBSD) and high (spatial) resolution-digital image correlation (HR-DIC) strain measurement techniques. Experimentally, this sample has been subjected to heat treatment leading to the establishment of residual (elastic) strains local to the agglomerate and subsequently loaded under conditions of low cyclic fatigue. The full thermal and mechanical loading history was reproduced within the model. HR-EBSD and HR-DIC elastic and total strain measurements demonstrate qualitative and quantitative agreement with crystal plasticity results. Crack nucleation by interfacial decohesion at the nickel matrix/agglomerate inclusion boundaries is observed experimentally, and systematic modelling studies enable the mechanistic basis of the nucleation to be established. A number of fatigue crack nucleation indicators are also assessed against the experimental results. Decohesion was found to be driven by interface tensile normal stress alone, and the interfacial strength was determined to be in the range of 1270-1480 MPa.

  7. The Process Design of Heavy Trucks Non-metallic Parts Coating Shop%重型卡车非金属件涂装车间工艺设计

    Institute of Scientific and Technical Information of China (English)

    张亚伦

    2012-01-01

    本文以新建重型卡车非金属件涂装线为例,详细介绍了非金属件面漆涂装的工艺流程、涂装工艺设备、辅助设备及物流方向,以及在线体空间极其有限的情况下需要考虑的主要因素,通过对主要因素的优化组合,得出了最佳工艺设计方案。%Nonmetal paint painting process, coating process equipment and auxiliary equipment, logistics direction and the main factors need to consider at the space extremely limited conditions were introduced in detail in this paper by using the new heavy trucks non-metal parts coating line as an example, the best process design was got by optimum combination of main factors.

  8. Formation Reason and Countermeasures of Non-Metal Inclusions of Cast Irons%铸铁非金属夹杂物的形成原因与应对措施

    Institute of Scientific and Technical Information of China (English)

    张文和; 王峰; 赵鲁生

    2011-01-01

    The composition and source of slag of cast irons melted in cupola and medium frequency furnace was introduced. The measures to reduce non-metal inclusions in cast irons were proposed as follows: ( 1 )improving metallurgical quality of the cast irons; (2 )improving the morphology and distribution of the nonmetal inclusions. The formation reason of the secondary slag was described. It's considered that, by adopting proper measures and iron melt treating technique, the secondary oxidation of the iron melt and its harmful effect can be reduced.%介绍了冲天炉和中频炉熔炼铸铁的炉渣成分及来源,提出减少铸铁内部非金属夹杂物的措施:(1)提高铸铁的冶金质量;(2)改善铸铁中非金属夹杂物的形态及分布.描述了铁液二次渣的形成原因,认为采取适宜的措施及铁液处理技术,可以减轻铁液二次氧化及其不利影响.

  9. Research on the Non-metallic Inclusion in X70 Pipeline Cast Slab%X70管线钢铸坯中非金属夹杂物的研究

    Institute of Scientific and Technical Information of China (English)

    吴雨晨; 李俊国; 闫小林; 李守章; 曾亚南

    2009-01-01

    利用大样电解、金相观测、扫描电镜(SEM)和电子探针(EPMA)等手段,对X70管线钢铸坯中夹杂物的数量、粒径、形貌及组分进行了研究.结果表明:X70管线钢铸坯中夹杂物数量较多,粒径较大,且多为复合夹杂.针对大型夹杂物中硫化物、氧化物、硅铝酸盐和钙铝酸盐复合夹杂的特点,分析了铸坯中夹杂物的主要来源.%Utilizing the methods of sample-electrolysing, metallographic observation, SEM and EPMA, the quantity, dimension, morphologies and composition of non-metallic inclusions in X70 pipeline steel cast slab were investigated. It was suggested that there were larger amount of inclusions with larger diam-eter in the cast slab. Most of these inclusions were complex, such as sulfide, oxide, silicon aluminates and calcium aluminates inclusions. According to the characteristics of inclusions in the east slab, the ma-jor sources of different inclusions were analyzed and explored.

  10. Determinación de la vida útil de las herramientas utilizadas en el barrenado de materiales no metálicos. // Determination of tools life in non-metallic materials drilling.

    Directory of Open Access Journals (Sweden)

    J. A. Cabrera Rodríguez

    2002-05-01

    Full Text Available En el barrenado de Placas de Circuito Impreso (PCI las barrenas de carburo de tungsteno son responsables de más de lamitad de los costos de la operación, siendo de vital importancia la búsqueda de vías para aumentar la eficiencia sin afectarla calidad del agujero.El siguiente artículo explica la implementación de una metodología para la determinación de la máxima cantidad deagujeros posibles de barrenar con una herramienta sin afectar los parámetros de calidad de los mismos en las condiciones ycon los medios disponibles en nuestro país. Esta metodología permitió elevar la vida útil de las herramientas en un 66%.Palabras claves: Barrenado, materiales no metálicos, circuitos impresos.________________________________________________________________________________AbstractIn the Printed Circuit Board (PCB drilling, the tools of tungsten carbide are responsible of more than half of the drillingcost. Due to is necessary look for ways to elevate the drilling efficiency without affect hole quality a methodology forseveral drilling in a PCB is given in the present paper.Key words: Drilling, non metalic materials, printe3d circuit board.

  11. An anionic two-dimensional indium carboxylate framework derived from a pseudo 3-symmetric semi-flexible tricarboxylic acid

    Indian Academy of Sciences (India)

    Pratap Vishnoi; Alok Ch Kalita; Ramaswamy Murugavel

    2014-09-01

    Hydrothermal treatment of indium(III) nitrate with a flexible pseudo 3-symmetric tricarboxylic acid at 115°C for 5 days in DMF yields a new layered anionic indium carboxylate framework, [(CH3)2 NH2)][In(L)(HCOO)(DMF)] (1) (L = 2,4,6-tris[(4′-carboxyphenoxy)methyl]-1,3,5-trimethylbenzene), existing as two-dimensional sheets. The framework solid has been characterized by elemental analysis, FT-IR spectroscopy, TGA, PXRD and single crystal X-ray diffraction studies. DMF undergoes cleavage to dimethyl ammonium and formate ions, which are incorporated in the framework. A slipped stacking of the two dimensional sheets along -axis in 1 results in a drastic decrease in the anticipated large porosity of the framework.

  12. 一种用于土壤非金属养分测试的光纤探头式分光光度计%An Optical-Fiber-Sensor-Based Spectrophotometer for Soil Non-Metallic Nutrient Determination

    Institute of Scientific and Technical Information of China (English)

    贺冬仙; 胡娟秀; 鲁绍坤; 何厚勇

    2012-01-01

    针对测土配方施肥技术中要求快速、便捷、高效地进行土壤养分测试的需求,文章基于浸入式光纤探头、平场凹面全息光栅、二极管线阵检测器开发了一种光纤探头式分光光度计用于土壤养分中非金属元素的快速、准确测试.基于国家计量检定规程JJG 178-2007对紫外、可见、近红外分光光度计的性能检测方法测试的该仪器的波长最大允许误差与波长重复性、基线平直度、透射比最大允许误差与透射比重复性均达到了国标第Ⅲ级别标准,其最小光谱带宽、噪声与漂移、杂散光基本达到了国标第Ⅳ级别标准.基于该仪器测试的土壤硝态氮、铵态氮、有效磷、有效硫、有效硼、和有机质含量与基于商用的国产单光束和进口双光束分光光度计测试的结果呈极显著的线性相关关系,其回归方程的斜率接近于1,且对比数据之间无显著性差异.因此,该光纤探头式分光光度计可用于土壤非金属养分的快速、准确测试.%In order to achieve rapid, convenient and efficient soil nutrient determination in soil testing and fertilizer recommendation, a portable optical-fiber-sensor-based spectrophotometer including immersed fiber sensor, flat field holographic concave grating, and diode array detector was developed for soil non-metallic nutrient determination. According to national standard of ultraviolet and visible spectrophotometer with JJG 178-2007, the wavelength accuracy and repeatability, baseline stability, transmittance accuracy and repeatability measured by the prototype instrument were satisfied with the national standard of III level; minimum spectral bandwidth, noise and excursion, and stray light were satisfied with the national standard of IV level. Significant linear relationships with slope of closing to 1 were found between the soil available nutrient contents including soil nitrate nitrogen, ammonia nitrogen, available phosphorus

  13. Mixed chloride/phosphine complexes of the dirhenium core. 10. Redox reactions of an edge-sharing dirhenium(III) non-metal-metal-bonded complex, Re(2)(mu-Cl)(2)Cl(4)(PMe(3))(4).

    Science.gov (United States)

    Cotton, F A; Dikarev, E V; Petrukhina, M A

    2001-12-17

    Reduction and oxidation reactions of the dirhenium(III) non-metal-metal-bonded edge-sharing complex, Re(2)(mu-Cl)(2)Cl(4)(PMe(3))(4) (1), have been studied. Several new mono- and dinuclear rhenium compounds have been isolated and structurally characterized in the course of this study. Reductions of 1 with 1 and 2 equiv of KC(8) result in an unusual face-sharing complex having an Re(2)(5+) core, Re(2)(mu-Cl)(3)Cl(2)(PMe(3))(4) (2), and a triply bonded Re(II) compound, 1,2,7,8-Re(2)Cl(4)(PMe(3))(4) (3), respectively. Two-electron reduction of 1 in the presence of tetrabutylammonium chloride affords a new triply bonded complex of the Re(2)(4+) core, [Bu(n)()(4)N][1,2,7-Re(2)Cl(5)(PMe(3))(3)] (4). Oxidation of 1 with NOBF(4) yields a Re(IV) mononuclear compound, trans-ReCl(4)(PMe(3))(2) (5). Two isomers of the monomeric Re(III) anion, [ReCl(4)(PMe(3))(2)](-) (6, 7), have been isolated as side products. The crystal structures of compounds 2 and 4-7 have been determined by X-ray crystallography. The Re-Re distance in the face-sharing complex 2 of 2.686(1) A is relatively short. The metal-metal bond length in anion 4 of 2.2354(7) A is consistent with the usual values for the triply bonded Re(2)(4+) core compounds. In addition, a cis arrangement of trimethylphosphine ligands in the starting material 1 is retained upon reduction in the dinuclear products 2-4.

  14. Fractal Dimension Study of Non-metallic Inclusion Images in Steel%钢中非金属夹杂物图像分形维数的研究

    Institute of Scientific and Technical Information of China (English)

    岳强; 张雅丽; 孔辉; 周俐; 王建军; 汪诚

    2012-01-01

    Binary images of non-metallic inclusions boundary were obtained by processing images of rolling material of 304/304L stainless steel with large inclusions and ingots with micro inclusions. Box-counting method was employed to compute fractal dimension of inclusion contour. Algorithm was implemented with MATLAB programming. Results show that the fractal dimension of inclusion is closely related to its composition and melting point. Morphologies of low melting point Al2O3-SiO2-CaO compound inclusion are sphere or similar sphere, their fractal dimensions are small, morphologies of high melting point Al2O3 inclusions and SiO2 inclusions are irregular, their fractal dimensions are large.%通过对304/304L不锈钢轧材中大型夹杂物和铸锭中显微夹杂物的图像进行处理,得到夹杂物边界的二值图像.采用计盒维数法对夹杂物轮廓的分形维数进行计算与分析,算法利用MATLAB编程实现.结果表明,夹杂物的分形维数与其组成和熔点密切相关,低熔点的Al2O3-SiO2-CaO系复合夹杂的形貌多为球形或类球形,其分形维数较小;高熔点的Al2O3夹杂物与SiQ2夹杂物的形貌多为不规则形,其分形维数较大.

  15. 304奥氏体不锈钢铸锭中非金属夹杂物研究%Research on Non-metallic Inclusions in 304 Austenitic Stainless Steel Ingot

    Institute of Scientific and Technical Information of China (English)

    张雅丽; 王建军; 罗林根; 郭上型; 孔辉; 周俐

    2011-01-01

    The type and the amount of the non-metallic inclusions in 304 stainless steel ingot were investigated, with a tracer used to find out the origin of inclusion. The results show that most of the micro inclusions are Al2Or-SiO2-CaO system inclusions, the micro inclusions (<5 urn) coexit amount of MgO-Al2O3 spinel inclusions;the macro inclusion is main to have two types of compound admixture, respectively is the type of Al2O3-SiOr-CaO.the type of Al2O3-SiO2; one of the main source of the non-matallic inclusions is the slag for the refractory corrosion in the molten steel during tapping; ladle lining affects slightly.%研究304不锈钢铸锭中非金属夹杂物的类型和数量,通过示踪剂分析不锈钢中夹杂物的来源.结果表明:不锈钢铸锭中显微夹杂物主要是以Al2O3-SiO2-CaO系硅酸盐夹杂为主,粒度<5μm的显微夹杂物中同时存在大量的镁铝尖晶石夹杂;大型夹杂物主要有两类复合夹杂物Al2O3-SiO2-CaO系夹杂、Al2O3-SiO2系夹杂;汤道耐火材料的侵蚀是夹杂物主要来源之一,钢包耐火材料对夹杂生成的影响微弱.

  16. Implementation and application of a method for quantifying metals and non-metals in drainage water from soils fertilized with phosphogypsum; Implementacao e aplicacao de metodologia para dosagem de metais e nao metais em aguas de drenagem de solos adubados com fosfogesso

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Camila Goncalves Bof

    2010-07-01

    Phosphogypsum is a waste generated in phosphoric acid production by the 'wet process'. The immense amount of phosphogypsum yearly produced (around 150 million tons) is receiving attention from environmental protection agencies all over the word, given its potential of contamination. In Brazil, this material has been used for many decades, especially for agricultural application on cropland. Although the phosphogypsum is mainly composed of dehydrated calcium sulfate, it can have high levels of impurities, such as metals (Cd, Cr, Cu, Pb), non-metals (As and Se) and radioactive elements from natural series of {sup 232}Th and {sup 238}U. Therefore, its continuous application as an agricultural agent can result not just in soil contamination, but also contamination of the surface and groundwater due to the runoff and infiltration process. The concern associated with the contamination of aquatic environments increases; when water is used for human consumption, requiring progressive adoption of more restrictive limits. However, some of the conventional analytical techniques used to determine the maximum limit of contaminants in water have detection limits above the maximum limits established by the environmental legislation. This work was aimed to evaluate the mobility of metals and non-metals in soils and, consequently, the contamination of drainage water through greenhouse-scale leaching and transport of toxic elements from soils fertilized with phosphogypsum. Hence, methods were studied and implemented for determination of metals (Cd, Cr, Cu and Pb) using Furnace Graphite Atomic Absorption Spectrometry (GF AAS), as well as for non-metals (As and Se) using Inductively Coupled Plasma Mass Spectrometry (lCP-MS). Effects of different chemical modifiers on the determination of Cd, Cr, Cu and Pb concentration by GF AAS were also investigated. In general, it was observed that the metal and non-metal concentration were below than the actual detection limit of the

  17. Research on Behavior of Non-metallic Inclusions in GCr15 Bearing Steel%GCr15轴承钢中非金属夹杂物行为的研究

    Institute of Scientific and Technical Information of China (English)

    张仰东; 吴晓东; 谈盛康

    2011-01-01

    Based on the productive process of BOF→LF→RH→CC for GCr15 bearing steel produced in Huaigang steel, using metallography and SEM-EDS analysis, the non-metallic inclusions in molten steel were studied in the size, composition and morphology. The changing about the inclusions in the bearing steel were investigated at different refining slag basicity. The main inclusions in rolling were mixed oxides and sulfide. The component diagram of inclusions were analyzed and calculated. The results show that micro-inclusions reduce from 23.34 number/mm2 into 14.02 number /mm2 after LF refining. Inclusions decrease slightly after RH treatment. The quantity of inclusions decrease slightly in rolling process. With the smelting process carrying out, the large inclusions are effectively removed by the steel flowing in ladle movement. The main inclusions in the steel are oxides, sulfide and CaO(CaS)-Al2O3-MgO complex inclusions.%针对淮钢80t转炉-90tLF- 100tRH-CC工艺生产的GCr15轴承钢,采用金相、SEM和EDS等方法,研究了精炼过程中夹杂物的尺寸、成分和形貌等的变化情况.经分析计算,得出了各工序夹杂物的成分图,并分析了夹杂物在冶炼过程中的变化规律.结果表明,在LF炉精炼后,微观夹杂物由23.34个/mm2下降到14.02个/mm2;经RH循环脱气处理后,夹杂物有所减少,成材中,夹杂物数量略有减少;随着冶炼过程的进行,大颗粒夹杂在钢包中随着钢流的运动得到了有效去除,细微夹杂物所占比例逐步升高;钢中存在的夹杂物主要有氧化物、硫化物以及CaO(CaS)-Al2O3-MgO类复合夹杂物.

  18. Increased Mortality in Metal-on-Metal versus Non-Metal-on-Metal Primary Total Hip Arthroplasty at 10 Years and Longer Follow-Up: A Systematic Review and Meta-Analysis

    Science.gov (United States)

    Meessen, J. M. T. A.; Fiocco, M.; van der Heide, H. J. L.; Sedrakyan, A.; Nelissen, R. G. H. H.

    2016-01-01

    Importance There are concerns about increased mortality in patients with metal-on-metal bearings in total hip arthroplasty (THA). Objective To determine the mortality and the morbidity in patients with metal-on-metal articulations (MOM THA) compared to patients with non-metal-on-metal articulations (non-MOM THA) after primary total hip arthroplasty. Data Sources Search of PubMed, MEDLINE, EMBASE, Web of Science, Cochrane, CINAHL, AcademicSearchPremier, ScienceDirect, Wiley and clinical trial registers through March 2015, augmented by a hand search of references from the included articles. No language restrictions were applied. Study Selection Two reviewers screened and identified randomised controlled trials and observational studies of primary total hip arthroplasty comparing MOM THA with non-MOM THA. Data Extraction and Synthesis Two reviewers independently extracted study data and assessed risk of bias. Risk differences (RD) were calculated with random effect models. Meta-regression was used to explore modifying factors. Main Outcomes and Measures Difference in mortality and difference in morbidity expressed as revisions and medical complications between patients with MOM THA and non-MOM THA. Results Forty-seven studies were included, comprising 4,000 THA in randomised trials and over 500,000 THA in observational studies. For mortality, random effects analysis revealed a higher pooled RD of 0.7%, 95%, confidence interval (CI) [0.0%, 2.3%], I-square 42%; the heterogeneity was explained by differences in follow-up. When restricted to studies with long term follow-up (i.e. 10 years or more), the RD for mortality was 8.5%, 95%, CI [5.8%, 11.2%]; number needed to treat was 12. Further subgroup analyses and meta-regression random effects models revealed no evidence for other moderator variables (study level covariates, e.g. resurfacing vs. non-resurfacing MOM) than follow-up duration. The quality of the evidence presented in this meta-analysis was characterized as

  19. Increased Mortality in Metal-on-Metal versus Non-Metal-on-Metal Primary Total Hip Arthroplasty at 10 Years and Longer Follow-Up: A Systematic Review and Meta-Analysis.

    Directory of Open Access Journals (Sweden)

    B G Pijls

    Full Text Available There are concerns about increased mortality in patients with metal-on-metal bearings in total hip arthroplasty (THA.To determine the mortality and the morbidity in patients with metal-on-metal articulations (MOM THA compared to patients with non-metal-on-metal articulations (non-MOM THA after primary total hip arthroplasty.Search of PubMed, MEDLINE, EMBASE, Web of Science, Cochrane, CINAHL, AcademicSearchPremier, ScienceDirect, Wiley and clinical trial registers through March 2015, augmented by a hand search of references from the included articles. No language restrictions were applied.Two reviewers screened and identified randomised controlled trials and observational studies of primary total hip arthroplasty comparing MOM THA with non-MOM THA.Two reviewers independently extracted study data and assessed risk of bias. Risk differences (RD were calculated with random effect models. Meta-regression was used to explore modifying factors.Difference in mortality and difference in morbidity expressed as revisions and medical complications between patients with MOM THA and non-MOM THA.Forty-seven studies were included, comprising 4,000 THA in randomised trials and over 500,000 THA in observational studies. For mortality, random effects analysis revealed a higher pooled RD of 0.7%, 95%, confidence interval (CI [0.0%, 2.3%], I-square 42%; the heterogeneity was explained by differences in follow-up. When restricted to studies with long term follow-up (i.e. 10 years or more, the RD for mortality was 8.5%, 95%, CI [5.8%, 11.2%]; number needed to treat was 12. Further subgroup analyses and meta-regression random effects models revealed no evidence for other moderator variables (study level covariates, e.g. resurfacing vs. non-resurfacing MOM than follow-up duration. The quality of the evidence presented in this meta-analysis was characterized as moderate according to the CLEAR-NPT (for non-pharmacological trials and Cochrane risk of bias Table

  20. Analysis of non-metallic inclusions in steel by SEM/EDS experiences with the technique as applied to the plain carbon steel Cf53 (1.1213); Analyse nichtmetallischer Einschluesse in Stahl mittels REM/EDS und Anwendung auf den unlegierten Kohlenstoffstahl Cf53 (1.1213)

    Energy Technology Data Exchange (ETDEWEB)

    Lietzau, Jens [GKN Driveline International GmbH, Lohmar (Germany). Research and Product Development Centre

    2010-12-15

    The SEM/EDS provides detailed information on the chemical nature of the non-metallic inclusions present in a steel. However, this information cannot be accepted uncritically. There can be positive and negative preparation artefacts and inclusions might be mis-classified because some elements are not or wrongly identified. Also, this detailed information comes at the cost of considerably longer measurement times than automated LM inclusion analyses require, since LM image acquisition is faster and no time is spent on EDS. (orig.)

  1. Electrophoretic mobility of semi-flexible double-stranded DNA in defect-controlled polymer networks: Mechanism investigation and role of structural parameters.

    Science.gov (United States)

    Khairulina, Kateryna; Li, Xiang; Nishi, Kengo; Shibayama, Mitsuhiro; Chung, Ung-il; Sakai, Takamasa

    2015-06-21

    Our previous studies have reported an empirical model, which explains the electrophoretic mobility (μ) of double-stranded DNA (dsDNA) as a combination of a basic migration term (Rouse-like or reptation) and entropy loss term in polymer gels with ideal network structure. However, this case is of exception, considering a large amount of heterogeneity in the conventional polymer gels. In this study, we systematically tune the heterogeneity in the polymer gels and study the migration of dsDNA in these gels. Our experimental data well agree with the model found for ideal networks. The basic migration mechanism (Rouse-like or reptation) persists perfectly in the conventional heterogeneous polymer gel system, while the entropy loss term continuously changes with increase in the heterogeneity. Furthermore, we found that in the limit where dsDNA is shorter than dsDNA persistence length, the entropy loss term may be related to the collisional motions between DNA fragments and the cross-links.

  2. Sodium dimercaptopropane sulfonate as antidote against non-metallic pesticides

    Institute of Scientific and Technical Information of China (English)

    Zhi-kang CHEN; Zhong-qiu LU

    2004-01-01

    @@ INTRODUCTION With the advent of World War II, dimercaptol was first developed in England as an effective antidote against arsenical agents. In 1950' s, scientists from the Soviet Union developed a water-soluble compound, sodium dimercaptopropane sulfonate (Na-DMPS) named as Unithiol (or Unitiol), which was able to chelate heavy metals and metalloids.

  3. System definition study of deployable, non-metallic space structures

    Science.gov (United States)

    Stimler, F. J.

    1984-01-01

    The state of the art for nonmetallic materials and fabrication techniques suitable for future space structures are summarized. Typical subsystems and systems of interest to the space community that are reviewed include: (1) inflatable/rigidized space hangar; (2) flexible/storable acoustic barrier; (3) deployable fabric bulkhead in a space habitat; (4) extendible tunnel for soft docking; (5) deployable space recovery/re-entry systems for personnel or materials; (6) a manned habitat for a space station; (7) storage enclosures external to the space station habitat; (8) attachable work stations; and (9) safe haven structures. Performance parameters examined include micrometeoroid protection; leakage rate prediction and control; rigidization of flexible structures in the space environment; flammability and offgassing; lifetime for nonmetallic materials; crack propagation prevention; and the effects of atomic oxygen and space debris. An expandable airlock for shuttle flight experiments and potential tethered experiments from shuttle are discussed.

  4. Non-metals in metals `98; Nichtmetalle in Metallen `98

    Energy Technology Data Exchange (ETDEWEB)

    Hirschfeld, D. [ed.

    1998-12-31

    The major topics discussed at the symposium are: (1) Thermodynamics and cinetics, (2) chemical, physical and physico-chemical examination methodology, (3) materials properties. 13 of the 25 papers presented at the symposium have been analysed and indexed for separate retrieval from the database. (orig./CB) [Deutsch] Themenschwerpunkte des diesjaehrigen Symposiums `Nichtmetalle in Metallen` sind: 1. Thermodynamik und Kinetik, 2. Chemische, physikalische und physikalisch-chemische Untersuchungsmethoden, und 3. Werkstoffeigenschaften. Von den insgesamt 25 Vortraegen wurden 13 Beitraege separat aufgenommen. (orig./MM)

  5. Laser -Based Joining of Metallic and Non-metallic Materials

    Science.gov (United States)

    Padmanabham, G.; Shanmugarajan, B.

    Laser as a high intensity heat source can be effectively used for joining of materials by fusion welding and brazing in autogenous or in hybrid modes. In autogenous mode, welding is done in conduction , deep penetration , and keyhole mode. However, due to inherently high energy density available from a laser source, autogenous keyhole welding is the most popular laser welding mode. But, it has certain limitations like need for extremely good joint fit-up, formation of very hard welds in steel , keyhole instability, loss of alloying elements, etc. To overcome these limitations, innovative variants such as laser-arc hybrid welding , induction-assisted welding , dual beam welding , etc., have been developed. Using laser heat, brazing can be performed by melting a filler to fill the joints, without melting the base materials. Accomplishing laser-based joining as mentioned above requires appropriate choice of laser source, beam delivery system, processing head with appropriate optics and accessories. Basic principles of various laser-based joining processes, laser system technology, process parameters, metallurgical effects on different base materials, joint performance, and applications are explained in this chapter.

  6. Doped Graphene as Non-Metallic Catalyst for Fuel Cells

    Directory of Open Access Journals (Sweden)

    Adriana MARINOIU

    2017-05-01

    Full Text Available Aiming a commercial development of proton exchange membrane fuel cells (PEMFC, a low cost, sustainable and high performance electrocatalyst for oxygen reduction reaction (ORR with capability to replace/reduce rare metals, are high desirable. In this paper, we present a class of doped graphene, namely iodinated graphene with highly ORR electrochemical performances, synthesized by using the electrophilic substitution method. The prepared samples were characterized by different techniques, including Scanning Electron Microscopy SEM, X-ray photoelectron spectroscopy XPS, Raman spectroscopy, surface area measurement by BET method, that revealed the structure and morphology. The most highly iodinated graphene was tested in a single cell by measuring the cyclic voltammetry. The electrochemical performances were evaluated and compared with a typical PEMFC configuration, when a single cathodic peak at 0.2 V with a current density of – 3.67 mA cm-2 for the Pt/C electrode was obtained. The best electrochemical performances in terms of electrochemical active area, was obtained for a new concept of cathode composed from Pt/C – iodine doped graphene, when a well-defined peak centred at 0.23 V with a current density of approx. – 9.1 mA cm-2 was obtained, indicating a high catalytic activity for ORR.DOI: http://dx.doi.org/10.5755/j01.ms.23.2.16216

  7. Nucleate boiling incipience over metallic/non-metallic surfaces

    Science.gov (United States)

    Petralanda, Naiara

    Incipience wall superheats over super-smooth Si, Al and Ti surfaces were collected at 1atm saturation conditions with FC-72 as the working fluid. Before experimentation, the fluid was put through a 2 hour degassing process to remove vapor. In addition a novel micro-heater was designed and fabricated that provided a constant temperature surface condition with slow heating rates. The average incipience wall superheats were 23.5K for Si, 26.4K for Al and 27.7K for Ti with a variance of less than 0.8K for all three cases. Contact angles were also measured; however, due to the highly wettability of the fluid, the resulting measurements showed large variability. For all cases, incipience occurred at approximately 30% of the homogeneous superheat limit predicted from classical theory. The observed differences in the wall superheat for the three surfaces was small. The primary surface heating element has a surface area of 250 mu m x 250mum which resulted in a very small Grashof number for the system. Consequently, the temperature profile over the heating element was evaluated from the steady Laplace equation using the Fourier integral method. Based on the critical radius at the time of incipience, it was determined that the temperature gradient over the vapor embryo is very small, and thus it can be assumed that the embryo is approximately equal to the wall temperature. Finally, since the measured surface roughness is an order of magnitude less than the critical radius for incipience it is concluded that nucleation could not have been initiated due to any vapor trapped within asperities on the surface. A theoretical framework based on homogeneous-like nucleation and the macroscopic contact angle is proposed. By analyzing the free energy barrier in terms of the vapor cluster, the liquid/vapor interface and the solid/vapor interface, the chemical potential at incipience for FC-72 and water can be determined from experimental measurements of wall superheat and liquid/vapor contact angle. Based on measured values of the chemical potential at incipience, the wall superheat at incipience for heterogeneous boiling on smooth surfaces can be determined.

  8. Study of irradiation effects in non-metallic conductors

    Energy Technology Data Exchange (ETDEWEB)

    Atobe, Kozo; Fukuoka, Noboru; Honda, Makoto; Kondo, Tadashi; Morishima, Kouichi [Naruto Univ. of Education, Naruto, Tokushima (Japan). Faculty of Science; Okada, Moritami; Nakagawa, Masuo

    1998-01-01

    The production of point defects induced by reactor and the thermal behavior of defects in sintered AlN and c-BN have been investigated using the optical absorption and electron spin resonance (ESR) methods. The absorption band at 370 nm (AlN) and the structureless absorption over the visible region are observed. These specimens also show ESR signals with g-value 2.007 (AlN), 2.006 (BN), which are probably caused by N vacancies with a trapped electron. In addition to these experiments, the difference of the photoluminescence(PL) lines on neutron irradiated CZ-Si and FZ-Si has been also studied. The models of the defect associated with neutron irradiation are discussed. (author)

  9. Effect of carbon fiber content on explosion-proof performance of spherical non-metallic separation explosion-proof material%碳纤维含量对球形非金属阻隔防爆材料防爆性能的影响

    Institute of Scientific and Technical Information of China (English)

    薄雪峰; 鲁长波; 杨真理; 朱祥东; 安高军; 解立峰

    2016-01-01

    在临界起爆能和高起爆能条件下,对装填碳纤维含量分别为6.5%、8.0%、9.5%和11.0%球形非金属阻隔防爆材料的油箱进行等效静爆试验,探究球形非金属阻隔防爆材料中碳纤维含量对其防爆性能的影响.利用红外热成像仪、高速摄像机分别记录油箱爆炸火球的温度场参数及爆炸过程,并与未填装阻隔防爆材料的油箱进行对比.试验结果表明:在临界起爆能条件下,装填4种材料的油箱均有一定阻燃防爆效果,油箱爆炸产生的燃料云团面积有依次减小的趋势;在高起爆能量条件下,4种材料的外场防爆性能分数分别为16.93、22.04、32.51、94.18,材料的防爆能力随着碳纤维含量的增加而增强.%Under the conditions of critical initiation energy and high initiation energy , the equivalent static explosion tests were carried out on the fuel tank which was filled by spherical non-metallic separation explosion-proof materials with the car-bon fiber content of 6.5%, 8%, 9.5%and 11%respectively, and the effect of carbon fiber content on explosion-proof per-formance of spherical non-metallic separation explosion-proof material was studied .The temperature field parameters and ex-plosion process of the explosive ball in the tank were recorded by the infrared thermal imaging system and high speed camera separately , and compared with those of the tank without filling separation explosion -proof material .The results showed that under the condition of critical initiation energy , all the tanks filled by four kinds of materials had a certain flame retardant and explosion-proof effect , and the area of fuel cloud produced by explosion of tank presented the trend of decrease in turn . Under the condition of high initiation energy , the scores of explosion-proof performance in external field for four kinds of ma-terials were 16.93, 22.04, 32.51 and 94.18 respectively, and the explosion-proof performance of the materials enhanced with

  10. Preparation and photocatalytic properties of La3+,Nd3+and non-metallic N doped TiO2%La3+、Nd3+与非金属氮共掺杂TiO2光催化剂的制备及其性能研究∗

    Institute of Scientific and Technical Information of China (English)

    赵斯琴; 长山; 张海玲; 杨杰

    2015-01-01

    采用溶胶-凝胶法制备了 TiO2、1% La/TiO2、1% Nd/TiO2和系列稀土 La3+和 Nd3+共掺杂TiO2光催化剂,进而结合水热法制备了双稀土 La3+、Nd3+和非金属氮共掺杂多元体系 TiO2光催化剂,并采用 XRD、UV-Vis、SEM 和 XPS 等测试手段对制备样品的微观结构、光谱学性能和离子掺杂形式进行了表征。研究表明,实验所制备样品均为锐钛矿型 TiO2光催化剂,稀土离子 La3+或 Nd3+的掺杂能有效抑制TiO2颗粒尺寸的生长,而且双稀土离子的共掺杂更有效抑制TiO2光催化剂颗粒尺寸的生长;非金属离子 N的掺杂,能有效拓宽 TiO2光催化剂的光响应范围;多元体系 TiO2光催化剂中,稀土钕以+3形式掺杂,非金属氮以-3形式掺杂。实验以甲基橙为目标污染物研究其光催化性能,研究表明,所制备的光催化剂均有较高的紫外光光催化性能,其中样品1%(La∶Nd,1∶7),N/TiO2的紫外光光催化性能最高,而且有较强的可见光光催化活性。%TiO2 ,1%-La/TiO2 ,1%-Nd/TiO2 and a series of La3+and Nd3+doped TiO2 photocatalysts were pre-pared by sol-gel method.Then,sol-gel method combined with hydrothermal method synthesized multi system of rare earth La,Nd,and nitrogen-doped TiO2 photocatalysts.Their microstructure,spectroscopic properties and ion doped form were characterized by X-ray powder diffraction (XRD),UV-Vis diffuse reflectance spectros-copy techniques,scanning electron microscopy (SEM),X-ray photoelectron spectroscopy (XPS).The catalytic activity was tested for the degradation of methyl orange solution.The results showed that,all the samples which prepared in paper were Anatase TiO2 photocatalysts,the doping of La3+ or Nd3+ could hinder the growth of TiO2 particle,even,the doping of La3+ with Nd3+ together could more effective hinder the growth of TiO2 particle;Non-metallic nitrogen-doped would broaden the Light response range of TiO2 photocatalyst.At the same time

  11. Non-Metallic Transducer Mounting Brackets (AN/BQQ-5/6 Spherical Array Transducers)

    Science.gov (United States)

    1992-06-15

    susceptible to moisture permeation into the bulk polymer phase, while moisture penetration into the glass-resin interface may be the predominant mechanism...material. These surface cracks appear to be present only in the hard liquid crystal polymer skin that forms during the molding of the Vectra material...Portsmouth Connector," NRL-USRD Letter Report No. 9464 to NAVSEA, 25 Apr 1988. 7. J.S. Thornton, R.E. Montgomery, and J.F. Cartier , "Failure Rate Model for

  12. Converting non-metallic printed circuit boards waste into a value added product.

    Science.gov (United States)

    Muniyandi, Shantha Kumari; Sohaili, Johan; Hassan, Azman; Mohamad, Siti Suhaila

    2013-01-01

    The aim of this study was to investigate the feasibility of using nonmetallic printed circuit board (PCB) waste as filler in recycled HDPE (rHDPE) in production of rHDPE/PCB composites. Maleic anhydride modified linear low-density polyethylene (MAPE) was used as compatibilizer. In particular, the effects of nonmetallic PCB and MAPE on mechanical properties of the composites were assessed through tensile, flexural and impact testing. Scanning electron microscope (SEM) was used to study the dispersion of nonmetallic PCB and MAPE in the matrix. Nonmetallic PCB was blended with rHDPE from 0-30 wt% and prepared by counter-rotating twin screw extruder followed by molding into test samples via hot press for analysis. A good balance between stiffness, strength and toughness was achieved for the system containing 30 wt% PCB. Thus, this system was chosen in order to investigate the effect of the compatibilizer on the mechanical properties of the composites. The results indicate that MAPE as a compatiblizer can effectively promote the interfacial adhesion between nonmetallic PCB and rHDPE. The addition of 6 phr MAPE increased the flexural strength, tensile strength and impact strength by 71%, 98% and 44% respectively compared to the uncompatibilized composites.

  13. Converting non-metallic printed circuit boards waste into a value added product

    OpenAIRE

    Shantha Kumari Muniyandi; Johan Sohaili; Azman Hassan; Siti Suhaila Mohamad

    2013-01-01

    The aim of this study was to investigate the feasibility of using nonmetallic printed circuit board (PCB) waste as filler in recycled HDPE (rHDPE) in production of rHDPE/PCB composites. Maleic anhydride modified linear low-density polyethylene (MAPE) was used as compatibilizer. In particular, the effects of nonmetallic PCB and MAPE on mechanical properties of the composites were assessed through tensile, flexural and impact testing. Scanning electron microscope (SEM) was used to study the dis...

  14. NATURE AND CHARACTER OF NON-METALLIC IMPURITIES IN HIGH-MANGANESE STEEL

    Directory of Open Access Journals (Sweden)

    A. I. Garost

    2006-01-01

    Full Text Available The nature of поп-metallic impurities of high-manganese wear-resistant steel is investigated by means of scanning electronic microscopy. The optimal compounds of complex additives (titan, vanadium, chromium, molybdenum, nitrogen, providing the highest operational characteristics of details, are determined.

  15. CHARACTERIZATION OF EMISSIONS FROM THE SIMULATED OPEN-BURNING OF NON-METALLIC AUTOMOBILE SHREDDER RESIDUE

    Science.gov (United States)

    The report gives results of a study in which the open combustion of a nonmetallic waste product called "fluff" was simulated and the resulting emissions collected and characterized to gain insight into the types and quantities of these air pollutants. (NOTE: The reclamation proce...

  16. Metallic and Non-Metallic Materials for the Primary Support Structure

    Energy Technology Data Exchange (ETDEWEB)

    RA Wolf; RP Corson

    2006-02-21

    The primary support structure (PSS) is required for mechanical support of reactor module (RM) components and mounting of the RM to the spacecraft. The PSS would provide support and accept all loads associated with dynamic (e. g., launch and maneuvering) or thermally induced loading. Prior to termination of NRPCT involvement in Project Prometheus, the NRPCT Mechanical Systems team developed preliminary finite element models to gain a basic understanding of the behavior of the structure, but optimization of the models, specification of the final design, and materials selection were not completed. The Space Plant Materials team had evaluated several materials for potential use in the primary support structure, namely titanium alloys, beryllium, aluminum alloys and carbon-carbon composites. The feasibility of application of each material system was compared based on mass, stiffness, thermal expansion, and ease of fabrication. Due to insufficient data on environmental factors, such as temperatures and radiation, and limited modeling support, a final materials selection was not made.

  17. Bonding, aromaticity and reactivity patterns in some all-metal and non-metal clusters

    Indian Academy of Sciences (India)

    S Duley; S Giri; A Chakraborty; P K Chattaraj

    2009-09-01

    Several sandwich-like metal clusters have been studied at the B3LYP/6-311 + G∗ level of theory. Bonding and reactivity have been analysed through various geometrical parameters and conceptual density functional theory based global reactivity descriptors. Aromaticity patterns have been understood in terms of the associated nucleus independent chemical shift values. Possibility of bond-stretch isomerism in some doped clusters is explored. Preferable sites for electrophilic and nucleophilic attacks have been identified using different local reactivity descriptors.

  18. Considerations for Storage of High Test Hydrogen Peroxide (HTP) Utilizing Non-Metal Containers

    Science.gov (United States)

    Moore, Robin E.; Scott, Joseph P.; Wise, Harry

    2005-01-01

    When working with high concentrations of hydrogen peroxide, it is critical that the storage container be constructed of the proper materials, those which will not degrade to the extent that container breakdown or dangerous decomposition occurs. It has been suggested that the only materials that will safely contain the peroxide for a significant period of time are metals of stainless steel construction or aluminum use as High Test Hydrogen Peroxide (HTP) Containers. The stability and decomposition of HTP will be also discussed as well as various means suggested in the literature to minimize these problems. The dangers of excess oxygen generation are also touched upon.

  19. Capacitance probe for detection of anomalies in non-metallic plastic pipe

    Science.gov (United States)

    Mathur, Mahendra P.; Spenik, James L.; Condon, Christopher M.; Anderson, Rodney; Driscoll, Daniel J.; Fincham, Jr., William L.; Monazam, Esmail R.

    2010-11-23

    The disclosure relates to analysis of materials using a capacitive sensor to detect anomalies through comparison of measured capacitances. The capacitive sensor is used in conjunction with a capacitance measurement device, a location device, and a processor in order to generate a capacitance versus location output which may be inspected for the detection and localization of anomalies within the material under test. The components may be carried as payload on an inspection vehicle which may traverse through a pipe interior, allowing evaluation of nonmetallic or plastic pipes when the piping exterior is not accessible. In an embodiment, supporting components are solid-state devices powered by a low voltage on-board power supply, providing for use in environments where voltage levels may be restricted.

  20. Realistic tunnelling states for the magnetic effects in non-metallic real glasses

    Science.gov (United States)

    Jug, Giancarlo; Bonfanti, Silvia; Kob, Walter

    2016-03-01

    The discovery of magnetic and compositional effects in the low-temperature properties of multi-component glasses has prompted the need to extend the standard two-level systems (2LSs) tunnelling model. A possible extension assumes that a subset of tunnelling quasi-particles is moving in a three-welled potential (TWP) associated with the ubiquitous inhomogeneities of the disordered atomic structure of the glass. We show that within an alternative, cellular description of the intermediate-range atomic structure of glasses the tunnelling TWP can be fully justified. We then review how the experimentally discovered magnetic effects can be explained within the approach where only localized atomistic tunnelling 2LSs and quasi-particles tunnelling in TWPs are allowed. We discuss the origin of the magnetic effects in the heat capacity, dielectric constant (real and imaginary parts), polarization echo and SQUID magnetization in several glassy systems. We conclude by commenting on a strategy to reveal the mentioned tunnelling states (2LSs and TWPs) by means of atomistic computer simulations and discuss the microscopic nature of the tunnelling states in the context of the potential energy landscape of glass-forming systems

  1. Synthesis of high molecular weight PEO using non-metal initiators

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jin; Sivanandan, Kulandaivelu; Pistorino, Jonathan; Eitouni, Hany Basam

    2015-05-19

    A new synthetic method to prepare high molecular weight poly(ethylene oxide) with a very narrow molecular weight distribution (PDI<1.5) is described. The method involves a metal free initiator system, thus avoiding dangerous, flammable organometallic compounds.

  2. Economic and ecologic importance of the non - metalic deposits in basalt maars of Southern Slovakia

    Directory of Open Access Journals (Sweden)

    Vass Dionýz

    1998-03-01

    Full Text Available By investigation of the basalt maars infill in Luèenská kotlina Depression the diatomite and alginite deposits have been found. Both maars belong to Podreèany basalt formation, Pontian (Late Miocene in age. By technological investigation it was proved the diatomite can be used in the building trade as raw materil for light tiles convenient especially for the construction of the saddle roof with attic appatments. The alginite can be used in the agriculture and horticulture, as a fertiliser becouse of humus, nutritive end same trace elements, a desodorant in livestoc feedlots, a water and nutritive elements trap to distribute them for the growing plants. The alginite can be used as well as in pharmacy and in different industrial branches. Both deposits are of high significance for the ecology and the nature protection.

  3. Nuclear Polarization of Molecular Hydrogen Recombined on a Non-metallic Surface

    CERN Document Server

    Airapetian, A; Akopov, Z; Amarian, M; Ammosov, V V; Andrus, A; Aschenauer, E C; Augustyniak, W; Avakian, R; Avetisian, A; Avetissian, E; Bailey, P; Baturin, V; Baumgarten, C; Beckmann, M; Belostotskii, S; Bernreuther, S; Bianchi, N; Blok, H P; Böttcher, Helmut B; Borisov, A; Bouwhuis, M; Brack, J; Brüll, A; Bryzgalov, V V; Capitani, G P; Chiang, H C; Ciullo, G; Contalbrigo, M; Dalpiaz, P F; De Leo, R; De Nardo, L; De Sanctis, E; Devitsin, E G; Di Nezza, P; Düren, M; Ehrenfried, M; Elalaoui-Moulay, A; Elbakian, G M; Ellinghaus, F; Elschenbroich, U; Ely, J; Fabbri, R; Fantoni, A; Feshchenko, A; Felawka, L; Fox, B; Franz, J; Frullani, S; Gärber, Y; Gapienko, G; Gapienko, V; Garibaldi, F; Garrow, K; Garutti, E; Gaskell, D; Gavrilov, G E; Karibian, V; Graw, G; Grebenyuk, O; Greeniaus, L G; Hafidi, K; Hartig, M; Hasch, D; Heesbeen, D; Henoch, M; Hertenberger, R; Hesselink, W H A; Hillenbrand, A; Hoek, M; Holler, Y; Hommez, B; Iarygin, G; Ivanilov, A; Izotov, A; Jackson, H E; Jgoun, A; Kaiser, R; Kinney, E; Kiselev, A; Königsmann, K C; Kopytin, M; Korotkov, V A; Kozlov, V; Krauss, B; Krivokhizhin, V G; Lagamba, L; Lapikas, L; Laziev, A; Lenisa, P; Liebing, P; Lindemann, T; Lipka, K; Lorenzon, W; Lü, J; Maiheu, B; Makins, N C R; Marianski, B; Marukyan, H O; Masoli, F; Mexner, V; Meyners, N; Miklukho, O; Miller, C A; Miyachi, Y; Muccifora, V; Nagaitsev, A; Nappi, E; Naryshkin, Yu; Nass, A; Negodaev, M A; Nowak, Wolf-Dieter; Oganessyan, K; Ohsuga, H; Orlandi, G; Pickert, N; Potashov, S Yu; Potterveld, D H; Raithel, M; Reggiani, D; Reimer, P E; Reischl, A; Reolon, A R; Riedl, C; Rith, K; Rosner, G; Rostomyan, A; Rubacek, L; Ryckbosch, D; Salomatin, Yu I; Sanjiev, I; Savin, I; Scarlett, C; Schäfer, A; Schill, C; Schnell, G; Schüler, K P; Schwind, A; Seele, J; Seidl, R; Seitz, B; Shanidze, R G; Shearer, C; Shibata, T A; Shutov, V B; Simani, M C; Sinram, K; Stancari, M D; Statera, M; Steffens, E; Steijger, J J M; Stewart, J; Stösslein, U; Tait, P; Tanaka, H; Taroian, S P; Tchuiko, B; Terkulov, A R; Tkabladze, A V; Trzcinski, A; Tytgat, M; Vandenbroucke, A; Van der Nat, P B; van der Steenhoven, G; Vetterli, Martin C; Vikhrov, V; Vincter, M G; Visser, J; Vogel, C; Vogt, M; Volmer, J; Weiskopf, C; Wendland, J; Wilbert, J; Ybeles-Smit, G V; Yen, S; Zihlmann, B; Zohrabyan, H G; Zupranski, P

    2004-01-01

    The nuclear polarization of $\\mathrm{H}_2$ molecules formed by recombination of nuclear polarized H atoms on the surface of a storage cell initially coated with a silicon-based polymer has been measured by using the longitudinal double-spin asymmetry in deep-inelastic positron-proton scattering. The molecules are found to have a substantial nuclear polarization, which is evidence that initially polarized atoms retain their nuclear polarization when absorbed on this type of surface

  4. Interaction of Non-Metallic Inclusion Particles with Advancing Solidification Front

    Directory of Open Access Journals (Sweden)

    Kalisz D.

    2014-06-01

    Full Text Available Praca zajmuje się zjawiskiem oddziały wania przemieszczającego frontu krystalizacji na cząstki wydzieleń niemetalicznych. Analizowano zachowanie pojedynczej cząstki wydzielenia w pobliżu poziomego i pionowego frontu. Scharakteryzowano siły działające na cząstkę w pobliżu frontu i sformułowano warunek równowagi, z którego wynika szybkość krytyczna frontu. Wyniki obliczeń zilustrowano w postaci wykresów.

  5. Agglomeration of Non-metallic Inclusions at the Steel/Ar Interface: Model Application

    Science.gov (United States)

    Mu, Wangzhong; Dogan, Neslihan; Coley, Kenneth S.

    2017-08-01

    Inclusion agglomeration is an important element in several industrial problems during steelmaking, such as nozzle clogging. In parallel work by the authors, a revised Kralchevsky-Paunov model has been established and the performance of this model has been validated against the experimental data from in-situ observations using confocal laser scanning microscopy. In this work, the revised model has been applied to quantitatively evaluate the attractive capillary force for the agglomeration of various inclusions at the interface between Ar and liquid iron/steel. A parametric study of the effects on the capillary force of the inclusion density, contact angle between the inclusion and liquid steel, and the surface tension of the liquid metal are quantitatively investigated. The results show that inclusion density and contact angle have a more marked effect on the capillary force than surface tension of liquid metal. Moreover, the inclusion agglomeration behavior in the liquid iron/steel matrix is discussed. The coagulation coefficient of various inclusions is calculated. Both the calculation results of the attractive capillary force of inclusions at the interface between Ar and liquid iron/steel and coagulation coefficient of inclusions in the liquid iron/steel matrix can offer a close agreement; moreover, the order of magnitude of inclusion agglomeration tendency is suggested. By using the coagulation coefficient, the inclusion collision volume and collision rate are calculated and the effects of inclusion composition, size, and number density are investigated. The evaluation results show that the tendency for affecting inclusion collision is inclusion number density > inclusion size > inclusion composition.

  6. Crack barriers improve the mechanical and thermal properties of non-metallic sinter materials

    Science.gov (United States)

    Gruenthaler, K. H.; Heinrich, W.; Janes, S.; Nixdorf, J.

    1979-01-01

    Means of improving the tensile strength of ceramic composites by introducing ductile intermediate layers capable of absorbing the elastic energy at the rupture front are studied. Tests with an Al203 laminate with niobium inclusions showed that crack propagation could be successfully precluded by dissipation of the energy by deformation and/or delamination at the inclusion/matrix interface.

  7. Converting Non-Metallic Printed Circuit Boards Waste Into A Value Added Product

    Directory of Open Access Journals (Sweden)

    Shantha Kumari Muniyandi

    2013-05-01

    Full Text Available The aim of this study was to investigate the feasibility of using nonmetallic printed circuit board (PCB waste as filler in recycled HDPE (rHDPE in production of rHDPE/PCB composites. Maleic anhydride modified linear low-density polyethylene (MAPE was used as compatibilizer. In particular, the effects of nonmetallic PCB and MAPE on mechanical properties of the composites were assessed through tensile, flexural and impact testing. Scanning electron microscope (SEM was used to study the dispersion of nonmetallic PCB and MAPE in the matrix. Nonmetallic PCB was blended with rHDPE from 0--30 wt% and prepared by counter-rotating twin screw extruder followed by molding into test samples via hot press for analysis. A good balance between stiffness, strength and toughness was achieved for the system containing 30 wt% PCB. Thus, this system was chosen in order to investigate the effect of the compatibilizer on the mechanical properties of the composites. The results indicate that MAPE as a compatiblizer can effectively promote the interfacial adhesion between nonmetallic PCB and rHDPE. The addition of 6 phr MAPE increased the flexural strength, tensile strength and impact strength by 71%, 98% and 44% respectively compared to the uncompatibilized composites.

  8. General problems of technical diagnosis of non-metal building structures in explotable buildings and erections

    Directory of Open Access Journals (Sweden)

    V.G. Shtengel

    2010-11-01

    Full Text Available For successful realization of survey it is necessary to solve varioius technical and organizational problems. Each of them influence on completeness and reliability of information and thus, objectivity of conclusions about real state of structures and building as a whole, and also forecasting of its further exploitation. In the article the classification and brief analysis of these problems is given.

  9. Quantum-chemical approach to defect formation processes in non-metallic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Kotomin, E.A.; Shluger, A.L. (Latvijskij Gosudarstvennyj Univ., Riga (USSR))

    1989-01-01

    Results of the quantum-chemical simulation of the formation of structural and radiation defects are reviewed, using ice, silicon, and silicon dioxide as examples. The relationship between the structural elements of these crystals and the structural defects is analysed. Models of the main defects, their optical characteristics, and the activation energy of their migration are discussed. The relationship between the characteristics obtained by quantum-chemical calculations and the parameters of the macroscopic kinetics of the processes induced by defects in dielectric crystals is considered. (author).

  10. Inductive sensor to detect metal impurities in non-metallic medium

    Science.gov (United States)

    Bykovsky, N. A.; Puchkova, L. N.; Fanakova, N. N.

    2017-02-01

    The mathematical model for an induction detector intended for detection of metal impurities is examined. The detector consists of three coils. The centre coil serves to induct a magnetic moment in the metal sample, and side coils are used to record this moment during the sample propulsion through the detector. It is shown that at an identical value of the magnetic field induction, created by the induction coil in the unit volume of the sample, the induced magnetic moment is defined by magnetic susceptibility for ferromagnetics, and for nonmagnetic materials – by their electric conductivity.

  11. Impact of defectiveness on the parameters of the acoustoelectric transformations in heterogeneous non-metallic materials

    Science.gov (United States)

    Fursa, T. V.; Lyukshin, B. A.; Utsyn, G. E.; Dann, D. D.

    2015-04-01

    The article studies acoustoelectric transformations of concrete with a crack. The research presents three-dimensional modeling and 3D visualization of wave processes in a concrete sample with a surface crack. The parameters of the electrical response are found to reflect the processes of interaction between the acoustic wave front and the defect and boundaries of the sample.

  12. FORMULATION OF EXPANSIVE MORTAR TO TILL THE STONES USING NON-METALLIC MINERALS OF NORTHEAST OF COUNTRY

    Directory of Open Access Journals (Sweden)

    Danielly Vieira de Lucena

    2015-03-01

    Full Text Available One of the most significant methods of advanced technology for mining, the rock massif is employing expansive mortar for cutting of Rock. Furthermore, the entire expansive mortar commercialized in the Brazilian domestic market are imported, as well as those in industrialized country. Both have components from the external market. The aim of this work is to develop expansive mortar with raw materials that have regional and pressure sufficient to remove the rocks of granite and marble type expansion. For this, expansive grout formulations using calcium oxide, calcium carbonate, carboxymethylcellulose are used - CMC (Portland cement, and from the chemical analysis by means of thermal analysis, X-ray diffraction and laser granulometry compared the results with a commercial mortar. The results indicated that the formulations showed characteristics similar to the commercial mortar.

  13. Inkjet printing of Chitlac-nanosilver--a method to create functional coatings for non-metallic bone implants.

    Science.gov (United States)

    Nganga, Sara; Moritz, Niko; Kolakovic, Ruzica; Jakobsson, Kristina; Nyman, Johan O; Borgogna, Massimiliano; Travan, Andrea; Crosera, Matteo; Donati, Ivan; Vallittu, Pekka K; Sandler, Niklas

    2014-12-01

    Biostable fiber-reinforced composites, based on bisphenol-A-dimethacrylate and triethyleneglycoldimethacrylate thermoset polymer matrix reinforced with E-glass fibers have been successfully used in cranial reconstructions and the material has been approved for clinical use. As a further refinement of these implants, antimicrobial, non-cytotoxic coatings on the composites were created by an immersion procedure driven by strong electrostatic interactions. Silver nanoparticles (nAg) were immobilized in lactose-modified chitosan (Chitlac) to prepare the bacteriostatic coatings. Herein, we report the use of inkjet technology (a drop-on-demand inkjet printer) to deposit functional Chitlac-nAg coatings on the thermoset substrates. Characterization methods included scanning electron microscopy, scanning white light interferometry and electro-thermal atomic absorption spectroscopy. Inkjet printing enabled the fast and flexible functionalization of the thermoset surfaces with controlled coating patterns. The coatings were not impaired by the printing process: the kinetics of silver release from the coatings created by inkjet printing and conventional immersion technique was similar. Further research is foreseen to optimize printing parameters and to tailor the characteristics of the coatings for specific clinical applications.

  14. One-Sided 3D Imaging of Non-Uniformities in Non-Metallic Space Flight Materials Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In this Phase II project, we propose to develop, construct, and deliver to NASA a prototype single-sided computed tomography time-domain terahertz (single-sided CT...

  15. A computer controlled mass spectrometer system for investigating the decomposition of non-metallic materials under atmospheric conditions

    Science.gov (United States)

    Thompson, J. M.

    1985-01-01

    A PDP 11/23 quadrupole mass spectrometer system was coupled to a nondiscriminating gas inlet system permitting gases at atmospheric pressure to be admitted into a high vacuum chamber containing the ion source of the mass spectrometer without separation of the gaseous components. The resolution of related software problems has resulted in a convenient computer-mass spectrometer system capable of generating masses, relative intensities and related data on the gaseous products resulting from the atmospheric thermal decomposition of nonmetallic materials.

  16. A General Qualitative Study of Point and Extended Defects and Their Interactions in Non-Metallic Systems.

    Science.gov (United States)

    1987-12-31

    Dickron Mergerlan, Ph.D. in physics at the Illinois Institute of Technology. 1965, Raymond R. Serway , Ph.D. in physics N at the Illinois Institute of...Temperature Dependence of the Hyperfine Structure Splittings of Some Trioxide Molecule Ions in Single Crystal Calcite. R. A. Serway , S. L. Chan and S...of Tetragonally Distorted Trivalent Chromium Ions in Magnesium Oxide. R. A. Serway , R. B. Robinson and S. A. Marshall, Phy. Stat. Sol. (b)56, 319

  17. Design and Development of Expanded Graphite-Based Non-metallic and Flexible Metamaterial Absorber for X-band Applications

    Science.gov (United States)

    Borah, Dipangkar; Bhattacharyya, Nidhi S.

    2016-09-01

    The possibility of using expanded graphite instead of a metallic layer as unit cells and ground planes for metamaterial absorbers in X-band is investigated. A metamaterial absorber was fabricated on a flexible linear low-density polyethylene substrate using an expanded graphite-based circular ring as the unit cell structure. The unit cell was simulated and optimized for which the metamaterial absorber exhibited 98.9% absorption at 11.22 GHz. The fabricated expanded graphite-based absorber showed a reflection loss of -24.51 dB at 11.56 GHz with -10 dB bandwidth of 0.39 GHz (3.37%). The performance of the same structure with copper was also measured. The expanded graphite-based metamaterial absorber showed enhanced performance as compared to the copper-based metamaterial absorber. The width of the ring was varied to tune the reflection loss. The proposed expanded graphite-based metamaterial absorber possesses the advantages of being ultra-thin, flexible and non-corrosive.

  18. Polarisation transform analysis for detection of shallow buried non-metallic landmines in microwave X-band region

    Science.gov (United States)

    Tiwari, K. C.; Singh, D.; Arora, M.

    2011-06-01

    Alternative approaches and models continue to be investigated and evolved to correctly locate and identify a buried mine with minimum risk. Though microwave remote sensing based detection of shallow buried landmines provides such a risk free alternative, it is a highly complex and computationally intensive task involving several parameters. The present paper deals with the use of data obtained in multiple polarizations and their transforms approximating rough surface conditions in sand for landmine detection. Data in both HH and VV polarizations in microwave X-band frequency (10 GHz, 3cm) was generated using a live landmine (with explosives less fuze) for the present study under field conditions. Various transforms such as image differencing, image ratioing and polarization discriminant ratio (PDR) were studied for its effect on landmine detection. However, it was found that most of the clutter and noise gets suppressed on using a transform obtained by subtracting the difference of data in two polarizations from its sum. The surface roughness conditions have been approximated as available in western parts of India and which are suitable for application of microwave radar remote sensing for detection of minefields. With the advent of satellites providing data in various polarizations, it has now become relevant to investigate methods which can be used for landmine detection using polarization techniques. The proposed analysis is expected to be useful in future in detection of landmines using multi-polarization satellite data in microwave X-band in deserts such as those existing in the western borders of India.

  19. Estimation of the ionic charge of non-metallic species into an electrical discharge through a web application

    Science.gov (United States)

    Pérez Gutiérrez, B. R.; Vera-Rivera, F. H.; Niño, E. D. V.

    2016-08-01

    Estimate the ionic charge generated in electrical discharges will allow us to know more accurately the concentration of ions implanted on the surfaces of nonmetallic solids. For this reason, in this research a web application was developed to allow us to calculate the ionic charge generated in an electrical discharge from the experimental parameters established in an ion implantation process performed in the JUPITER (Joint Universal Plasma and Ion Technologies Experimental Reactor) reactor. The estimated value of the ionic charge will be determined from data acquired on an oscilloscope, during startup and shutdown of electrical discharge, which will then be analyzed and processed. The study will provide best developments with regard to the application of ion implantation in various industrial sectors.

  20. Investigation of Fatigue Crack Initiation from a Non Metallic Inclusion via High Energy X Ray Diffraction Microscopy (Postprint)

    Science.gov (United States)

    2017-07-14

    heat treated coarse grain variant of RR1000, a polycrystalline Ni-based super- alloy with a face centered cubic (FCC) crystal structure elease (PA...directly used as input into the simulations. The perimeter of the volume in the directions perpendicular to loading had a buffer of a dummy/gas phase (all

  1. On the dissolution of non-metallic solid elements (sulfur, selenium, tellurium and phosphorus) in ionic liquids.

    Science.gov (United States)

    Boros, Eva; Earle, Martyn J; Gîlea, Manuela A; Metlen, Andreas; Mudring, Anja-Verena; Rieger, Franziska; Robertson, Allan J; Seddon, Kenneth R; Tomaszowska, Alina A; Trusov, Lev; Vyle, Joseph S

    2010-02-07

    Ionic liquids are shown to be good solvents for elemental sulfur, selenium, phosphorus and tellurium, and can be designed to maximise the solubility of these elements. The presence of the [S(3)](*-) radical anion in diluted solutions of sulfur in some ionic liquids has been confirmed, and is the origin of their intense blue colour (cf. lapis lazuli).

  2. A computer controlled mass spectrometer system for investigating the decomposition of non-metallic materials under atmospheric conditions

    Science.gov (United States)

    Thompson, J. M.

    1985-01-01

    A PDP 11/23 quadrupole mass spectrometer system was coupled to a nondiscriminating gas inlet system permitting gases at atmospheric pressure to be admitted into a high vacuum chamber containing the ion source of the mass spectrometer without separation of the gaseous components. The resolution of related software problems has resulted in a convenient computer-mass spectrometer system capable of generating masses, relative intensities and related data on the gaseous products resulting from the atmospheric thermal decomposition of nonmetallic materials.

  3. Determination for the Entrapment Criterion of Non-metallic Inclusions by the Solidification Front During Steel Centrifugal Continuous Casting

    Science.gov (United States)

    Wang, Qiangqiang; Zhang, Lifeng

    2016-06-01

    In the current study, the three-dimensional fluid flow, heat transfer, and solidification in steel centrifugal continuous casting strands were simulated. The volume of fluid model was used to solve the multiphase phenomena between the molten steel and the air. The entrapment and final distribution of inclusions in the solidified shell were studied with the discussion on the effect of rotation behavior of the caster system. Main results indicate that after applying the rotation of the shell, the fluid flow transformed from a recirculation flow to a rotation flow in the mold region and was driven to flow around in the casting direction. As the distance below the meniscus increased, the distribution of the tangential speed of the flow and the centrifugal force along one diameter of the strand became symmetrical gradually. The jet flow from the nozzle hardly impinged on the same location on the shell due to the rotation of the shell during solidification. Thus, the shell thickness on the same height was uniform around, and the thinning shell and a hot spot on the surface of shell were avoided. Both of the measurement and the calculation about the distribution of oxide inclusions along the radial direction indicated the number of inclusions at the side and the center was more than that at the quarter on the cross section of billet. With a larger diameter, inclusions tended to be entrapped toward the center area of the billet.

  4. Degradation of organic pollutants by Ag, Cu and Sn doped waste non-metallic printed circuit boards.

    Science.gov (United States)

    Ramaswamy, Kadari; Radha, Velchuri; Malathi, M; Vithal, Muga; Munirathnam, Nagegownivari R

    2017-02-01

    The disposal and reuse of waste printed circuit boards have been the major global concerns. Printed circuit boards, a form of Electronic waste (hereafter e-waste), have been chemically processed, doped with Ag(+), Cu(2+) and Sn(2+), and used as visible light photocatalysts against the degradation of methylene blue and methyl violet. The elemental analyses of pristine and metal doped printed circuit board were obtained using energy dispersive X-ray fluorescence (EDXRF) spectra and inductively coupled plasma optical emission spectroscopy (ICP-OES). The morphology of parent and doped printed circuit board was obtained from scanning electron microscopy (SEM) measurements. The photocatalytic activity of parent and metal doped samples was carried out for the decomposition of organic pollutants, methylene blue and methyl violet, under visible light irradiation. Metal doped waste printed circuit boards (WPCBs) have shown higher photocatalytic activity against the degradation of methyl violet and methylene blue under visible light irradiation. Scavenger experiments were performed to identify the reactive intermediates responsible for the degradation of methylene blue and methyl violet. The reactive species responsible for the degradation of MV and MB were found to be holes and hydroxyl radicals. A possible mechanism of degradation of methylene blue and methyl violet is given. The stability and reusability of the catalysts are also investigated.

  5. Monte Carlo simulations as a feasibility tool for non-metallic land-mine detection by thermal-neutron backscattering

    NARCIS (Netherlands)

    Maucec, M; de Meijer, RJ

    2002-01-01

    The use of Monte Carlo simulations is presented for modelling a simplified land-mine detector system with thermal neutron backscattering (TNB) analysis based on a Cf-252-neutron source. Different aspects and a variety of external conditions, related to localisation and identification of a buried obj

  6. Photocatalytic properties of metal and non-metal doped novel sub 10nm titanium dioxide nanoparticles on methyl orange.

    Science.gov (United States)

    McManamon, Colm; Delaney, Paul; Morris, Michael A

    2013-12-01

    This study examines the addition of various dopants to TiO2 nanoparticles for the enhancement of photocatalytic activity. The materials were tested for efficiency on the degradation of methyl orange under UV light. The dopants were added at different molar ratios to find the ideal amount required for optimum results. BET analysis was used to determine surface areas while X-ray diffraction (XRD) analysis was used to study the effect of the dopant on the transformation of the TiO2 structure. The dopants used were Ag, S and Zr and displayed high levels of activity and show some ability to be reused. Decomposition of methyl orange was carried out using a 40 W UV bulb at 365 nm and results were measured by UV-vis spectrometry. It was determined that, overall, Ag doping displayed the best photocatalytic properties but was poor upon reuse.

  7. Significance of bioleaching method in dissolution of iron and in the quality improvement of non-metallics

    Directory of Open Access Journals (Sweden)

    Iveta Štyriaková

    2006-12-01

    Full Text Available Simple laboratory bioleaching experiments for the iron removal with heterotrophic bacteria on natural raw materials were conducted to explore a simple cyclic operation for a potential use at the industrial scale. Heterotrophic bacteria of Bacillus spp. growing in the presence of feldspar raw materials are able to dissolve iron. Anaerobic conditions Quickly formed by bacteria enable a simple manipulation with the sample solution. Insoluble Fe(III in the feldspars sample could be enzymatically dissolved as Fe3+ and also reduced to soluble Fe2+ by silicate bacteria of Bacillus spp. This metal was efficiently removed from the feldspars sample as documented by a Fe2O3 decrease (from 0.29 % to 0.12 % after bioleaching in the conical flask and by a Fe2O3 decrease (from 0.29 % to 0.19 % after bioleaching in the percolate column. Bioleaching of Fe was more effective in the conical flask. Iron-bearing minerals can be easily removed by magnetic separation, but ultra fine iron particles are difficult to treat by conventional mineral processing methods. Thus bioleaching is an attractive alternative for effective removal of iron minerals. The removal of iron with the whiteness increase should give a product, which is fit for industrial ceramic applications.

  8. SIMULATION PROCESS OF REMOVING NON-METALLIC INCLUSIONS IN ALUMINUM ALLOYS USING THE PROGRAM FLOW-3D

    Directory of Open Access Journals (Sweden)

    N. V. Sletova

    2013-01-01

    Full Text Available The perspective materials for making fining preparations for the silumins are the calcium and strontium carbonates from the environmental safety point of view are shown. Principle possibility of using dispersed carbonates in the fining mixtures is confirmed by late inoculation process research using simulation FLOW-3D.The high efficiency of the fining mixture with the inoculants effect is confirmed by the industrial tests

  9. Agglomeration of Non-metallic Inclusions at Steel/Ar Interface: In- Situ Observation Experiments and Model Validation

    Science.gov (United States)

    Mu, Wangzhong; Dogan, Neslihan; Coley, Kenneth S.

    2017-10-01

    Better understanding of agglomeration behavior of nonmetallic inclusions in the steelmaking process is important to control the cleanliness of the steel. In this work, a revision on the Paunov simplified model has been made according to the original Kralchevsky-Paunov model. Thus, this model has been applied to quantitatively calculate the attractive capillary force on inclusions agglomerating at the liquid steel/gas interface. Moreover, the agglomeration behavior of Al2O3 inclusions at a low carbon steel/Ar interface has been observed in situ by high-temperature confocal laser scanning microscopy (CLSM). The velocity and acceleration of inclusions and attractive forces between Al2O3 inclusions of various sizes were calculated based on the CLSM video. The results calculated using the revised model offered a reasonable fit with the present experimental data for different inclusion sizes. Moreover, a quantitative comparison was made between calculations using the equivalent radius of a circle and those using the effective radius. It was found that the calculated capillary force using equivalent radius offered a better fit with the present experimental data because of the inclusion characteristics. Comparing these results with other studies in the literature allowed the authors to conclude that when applied in capillary force calculations, the equivalent radius is more suitable for inclusions with large size and irregular shape, and the effective radius is more appropriate for inclusions with small size or a large shape factor. Using this model, the effect of inclusion size on attractive capillary force has been investigated, demonstrating that larger inclusions are more strongly attracted.

  10. Non-metallic coating thickness prediction using artificial neural network and support vector machine with time resolved thermography

    Science.gov (United States)

    Wang, Hongjin; Hsieh, Sheng-Jen; Peng, Bo; Zhou, Xunfei

    2016-07-01

    A method without requirements on knowledge about thermal properties of coatings or those of substrates will be interested in the industrial application. Supervised machine learning regressions may provide possible solution to the problem. This paper compares the performances of two regression models (artificial neural networks (ANN) and support vector machines for regression (SVM)) with respect to coating thickness estimations made based on surface temperature increments collected via time resolved thermography. We describe SVM roles in coating thickness prediction. Non-dimensional analyses are conducted to illustrate the effects of coating thicknesses and various factors on surface temperature increments. It's theoretically possible to correlate coating thickness with surface increment. Based on the analyses, the laser power is selected in such a way: during the heating, the temperature increment is high enough to determine the coating thickness variance but low enough to avoid surface melting. Sixty-one pain-coated samples with coating thicknesses varying from 63.5 μm to 571 μm are used to train models. Hyper-parameters of the models are optimized by 10-folder cross validation. Another 28 sets of data are then collected to test the performance of the three methods. The study shows that SVM can provide reliable predictions of unknown data, due to its deterministic characteristics, and it works well when used for a small input data group. The SVM model generates more accurate coating thickness estimates than the ANN model.

  11. Thermal conductivity measurements of non-metals via combined time- and frequency-domain thermoreflectance without a metal film transducer

    Science.gov (United States)

    Wang, L.; Cheaito, R.; Braun, J. L.; Giri, A.; Hopkins, P. E.

    2016-09-01

    The thermoreflectance-based techniques time- and frequency-domain thermoreflectance (TDTR and FDTR, respectively) have emerged as robust platforms to measure the thermophysical properties of a wide array of systems on varying length scales. Routine in the implementation of these techniques is the application of a thin metal film on the surface of the sample of interest to serve as an opto-thermal transducer ensuring the measured modulated reflectivity is dominated by the change in thermoreflectance of the sample. Here, we outline a method to directly measure the thermal conductivities of bulk materials without using a metal transducer layer using a standard TDTR/FDTR experiment. A major key in this approach is the use of a thermal model with z-dependent heat source when the optical penetration depth is comparable to the beam sizes and measuring the FDTR response at a long delay time to minimize non-thermoreflectivity contributions to the modulated reflectance signals (such as free carrier excitations). Using this approach, we demonstrate the ability to measure the thermal conductivity on three semiconductors, intrinsic Si (100), GaAs (100), and InSb (100), the results of which are validated with FDTR measurements on the same wafers with aluminum transducers. We outline the major sources of uncertainty in this approach, including frequency dependent heating and precise knowledge of the pump and probe spot sizes. As a result, we discuss appropriate pump-frequency ranges in which to implement this TDTR/FDTR approach and present a procedure to measure the effective spot sizes by fitting the FDTR data of an 80 nm Al/SiO2 sample at a time delay in which the spot size sensitivity dominates an FDTR measurement over the substrate thermal properties. Our method provides a more convenient way to directly measure the thermal conductivities of semiconductors.

  12. Effective thermal conductivity of metal and non-metal particulate composites with interfacial thermal resistance at high volume fraction of nano to macro-sized spheres

    Energy Technology Data Exchange (ETDEWEB)

    Faroughi, Salah Aldin, E-mail: salah-faroughi@gatech.edu [School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta 30332-0340 (United States); Huber, Christian [School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta 30332-0340 (United States)

    2015-02-07

    In this study, we propose a theoretical model to compute the effective thermal conductivity of metal and dielectric spherical particle reinforced composites with interfacial thermal resistance. We consider a wide range of filler volume fraction with sizes ranging from nano- to macro-scale. The model, based on the differential effective medium theory, accounts for particle interactions through two sets of volume fraction corrections. The first correction accounts for a finite volume of composite and the second correction introduces a self-crowding factor that allows us to develop an accurate model for particle interaction even for high volume fraction of fillers. The model is examined to other published models, experiments, and numerical simulations for different types of composites. We observe an excellent agreement between the model and published datasets over a wide range of particle volume fractions and material properties of the composite constituents.

  13. Mines, Non-Coal (Abandoned), Non_metalic_mines_closed, Published in 2007, 1:600 (1in=50ft) scale, Buffalo County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Mines, Non-Coal (Abandoned) dataset, published at 1:600 (1in=50ft) scale, was produced all or in part from Orthoimagery information as of 2007. It is described...

  14. Mines, Non-Coal (Active), Non_metalic_mines_open, Published in 2007, 1:600 (1in=50ft) scale, Buffalo County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Mines, Non-Coal (Active) dataset, published at 1:600 (1in=50ft) scale, was produced all or in part from Orthoimagery information as of 2007. It is described as...

  15. X60钢非金属夹杂的控制措施%Control Measures for Non Metal Inclusions of Steel X60

    Institute of Scientific and Technical Information of China (English)

    孙作迎; 李强刚

    2016-01-01

    综合日钢X60钢生产现状,对A类、B类夹杂变性进行分析.认为,钢液内ACR应>1.8的条件,可满足A类夹杂完全变性;通过钢液内T[O]变化,预知B类夹杂相对数量,以达到[Ca]/[Al] >0.14,可达到B类夹杂完全变性.如何有效降低C类夹杂,需进一步探讨论证.

  16. Measurement of the half-life of 198Au in a non-metal: High-precision measurement shows no host-material dependence

    CERN Document Server

    Goodwin, J R; Iacob, V E; Dibidad, A; Hardy, J C

    2010-01-01

    We have measured the half-life of the beta decay of 198Au to be 2.6948(9) d, with the nuclide sited in an insulating environment. Comparing this result with the half-life we measured previously with a metallic environment, we find the half-lives in both environments to be the same within 0.04%, thus contradicting a prediction that screening from a "plasma" of quasi-free electrons in a metal increases the half-life by as much as 7%.

  17. 非金属矿物聚合材料的制备及性能研究%Preparation and Properties of Non-metallic Geopolymer

    Institute of Scientific and Technical Information of China (English)

    井强山; 王进双; 杨润桦

    2014-01-01

    以偏高岭土、粉煤灰为主要原料,沸石、黏土为辅料,生石灰和钠水玻璃为碱激发剂制备矿物聚合材料.通过正交试验研究了养护温度、养护时间、蒸养时间对抗压强度影响,通过单因素实验研究了生石灰用量、水固比及水玻璃模数对抗压强度影响;并通过红外光谱、X-射线衍射和扫描电镜分析了样品的化学键变化、物相组成及微观形貌.结果表明,最佳的养护条件为养护温度80℃、湿度95%,养护时间72 h,0.8 MPa蒸养8 h;生石灰用量、水固比、水玻璃模数的最佳值分别为3%(wt)、0.37、2.3,样品的最大抗压强度为60.8 MPa.%Geopolymer was prepared with fly ash and metakaolin as the main raw materials , natural zeolite and clay as the auxiliary materials , activated with sodium silicate and quicklime .Influence of curing temperature , curing time and autoclave curing time on compression strength were investigated by orthogonal experiments .Effects of quick-lime amount, water-solid ratio and sodium silicate modulus on compression strength were also studied by single factor experiment .Chemical bounding , phase composition and microstructure of geopolymer were characterized by FT-IR, XRD and SEM techniques .Results show that the optimized conditions are curing temperature of 80 ℃, humidity of 95%, curing time of 72 h, autoclaved curing at 0.8 Mpa for 8 h.Quicklime dosage, water solid ratio and the modulus of sodium silicate is 3%(wt), 0.37 and 2.3, respectively.The compression strength of the optimal sample is 60.8 MPa.

  18. Environmental Monitoring, Other, Non-Metallic Mine Site polygons, Published in 2013, 1:2400 (1in=200ft) scale, Vernon County Wisconsin.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Environmental Monitoring, Other dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Other information as of 2013. It is described...

  19. Mathematical Modeling on the Growth and Removal of Non-metallic Inclusions in the Molten Steel in a Two-Strand Continuous Casting Tundish

    Science.gov (United States)

    Ling, Haitao; Zhang, Lifeng; Li, Hong

    2016-10-01

    In the current study, mathematical models were developed to predict the transient concentration and size distribution of inclusions in a two-strand continuous casting tundish. The collision and growth of inclusions were considered. The contribution of turbulent collision and Stokes collision was evaluated. The removal of inclusions from the top surface was modeled by considering the properties of inclusions and the molten steel, such as the wettability, density, size, and interfacial tension. The effect of composition of inclusions on the collision of inclusions was included through the Hamaker constant. Meanwhile, the effect of the turbulent fluctuation velocity on the removal of inclusions at the top surface was also studied. Inclusions in steel samples were detected using automatic SEM Scanning so that the amount, morphology, size, and composition of inclusions were achieved. In the simulation, the size distribution of inclusions at the end steel refining was used as the initial size distribution of inclusions at tundish inlet. The equilibrium time when the collision and coalescence of inclusions reached the steady state was equal to 3.9 times of the mean residence time. When Stokes collision, turbulent collision, and removal by floating were included, the removal fraction of inclusions was 16.4 pct. Finally, the removal of solid and liquid inclusions, such as Al2O3, SiO2, and 12CaO·7Al2O3, at the interface between the molten steel and slag was studied. Compared with 12CaO·7Al2O3 inclusions, the silica and alumina inclusions were much easier to be removed from the molten steel and their removal fractions were 36.5 and 39.2 pct, respectively.

  20. A Fully Non-Metallic Gas Turbine Engine Enabled by Additive Manufacturing Part I: System Analysis, Component Identification, Additive Manufacturing, and Testing of Polymer Composites

    Science.gov (United States)

    Grady, Joseph E.; Haller, William J.; Poinsatte, Philip E.; Halbig, Michael C.; Schnulo, Sydney L.; Singh, Mrityunjay; Weir, Don; Wali, Natalie; Vinup, Michael; Jones, Michael G.; Patterson, Clark; Santelle, Tom; Mehl, Jeremy

    2015-01-01

    The research and development activities reported in this publication were carried out under NASA Aeronautics Research Institute (NARI) funded project entitled "A Fully Nonmetallic Gas Turbine Engine Enabled by Additive Manufacturing." The objective of the project was to conduct evaluation of emerging materials and manufacturing technologies that will enable fully nonmetallic gas turbine engines. The results of the activities are described in three part report. The first part of the report contains the data and analysis of engine system trade studies, which were carried out to estimate reduction in engine emissions and fuel burn enabled due to advanced materials and manufacturing processes. A number of key engine components were identified in which advanced materials and additive manufacturing processes would provide the most significant benefits to engine operation. The technical scope of activities included an assessment of the feasibility of using additive manufacturing technologies to fabricate gas turbine engine components from polymer and ceramic matrix composites, which were accomplished by fabricating prototype engine components and testing them in simulated engine operating conditions. The manufacturing process parameters were developed and optimized for polymer and ceramic composites (described in detail in the second and third part of the report). A number of prototype components (inlet guide vane (IGV), acoustic liners, engine access door) were additively manufactured using high temperature polymer materials. Ceramic matrix composite components included turbine nozzle components. In addition, IGVs and acoustic liners were tested in simulated engine conditions in test rigs. The test results are reported and discussed in detail.

  1. Quarries, Non-Metallic Mines, Published in 2008, 1:2400 (1in=200ft) scale, Jefferson County Land Information Office.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Quarries dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Published Reports/Deeds information as of 2008. It is described as...

  2. Surface rheological properties of liquid-liquid interfaces stabilized by protein fibrillar aggregates and protein-polysaccharide complexes

    NARCIS (Netherlands)

    Humblet-Hua, K.N.P.; Linden, van der E.; Sagis, L.M.C.

    2013-01-01

    In this study we have investigated the surface rheological properties of oil-water interfaces stabilized by fibrils from lysozyme (long and semi-flexible and short and rigid ones), fibrils from ovalbumin (short and semi-flexible), lysozyme-pectin complexes, or ovalbumin-pectin complexes. We have

  3. 非金属管道在煤层气气田工程中的应用%Application of Non-metallic Pipes in Coalbed Methane Gas Fields Project

    Institute of Scientific and Technical Information of China (English)

    王红霞; 陶永

    2009-01-01

    随着我国煤层气资源的开发,各个煤层气气田的建设也将陆续启动.适用于煤层气采气管网的聚乙烯(PE)管和柔性复合管以其经济性、耐腐蚀性、安全性等将得以推广应用.

  4. Influence of non-metallic second phases on fatigue behaviour of high strength steel components; Efecto de segundas fases no metalicas sobre el comportamiento a fatiga de componentes de acero con elevadas solicitaciones

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, L.; Elvira, R.; Garcia de Andoin, A.; Pizarro, R.; Bertrand, C.

    2005-07-01

    To assess the real effect of the inclusion type on fatigue life of ultra clean high strength steels mechanical components made of 100Cr6 steel were fatigue tested and fracture surfaces analysed to determine the origin of fatigue cracks.Two heats proceedings from different steelmaking routes were taken for the tests. The material were forged into ring shape components which were fatigue tested under compression-compression loads. Failures were analysed by SFEM (Scanning field Emission Microscopy), proving that most of failures at high loads were originated by manganese sulphides of small size (10-70 micros), while less than 40% of all fatigue cracks due to inclusions were caused by titanium carbonitrides and hard oxides. It has been demonstrated that once number and size of hard inclusions have been reduced, the hazardous effect of oxides and carbonitrides on the fatigue life decreases also. However, softer inclusions as manganese sulphides, currently considered as less hazardous, play a more relevant role as direct cause of fatigue failure and they should be taken into account in a deeper way in order to balance both machinability and fatigue life requirements in high strength steel components. (Author) 11 refs.

  5. 浅析国际非金属探雷器材发展现状与趋势%The Development of International Equipments for Non-Metal Landmine Detection

    Institute of Scientific and Technical Information of China (English)

    郭涛; 季茂荣; 沈蔚; 李德林

    2010-01-01

    本文概述了国际上非金属地雷探测技术的发展现状,分析对比了各种技术存在的优势以及局限,介绍了国外目前已经装备的几种先进的非金属探测器材,最后总结了未来非金属探测器材发展的主要趋势.

  6. GYM系列亿丰磨在非金属矿物超微粉碎中的应用%Application of GYM Series Yifeng Mill in Micronizing of Non-metal Mineral

    Institute of Scientific and Technical Information of China (English)

    孙成林; 王清发; 连钦明

    2004-01-01

    干法生产超细粉是我国非金属粉体的重要加工工艺之一,传统的粉磨设备难以达到大量生产d97=2~10μm超细粉的要求,且生产效率低.阐述了采用多磨轮、多磨道原理设计的GYM-83型亿丰磨在生产粒径为11μm的碳酸钙干粉时,其累积分布达98%,粒径为2 μm的占总质量44.96%,产量达到了1 250 kg/h,且基建投资少,性价比好.

  7. Effects of enhanced electronic correlation on magnetic properties of light non-metallic element (B, C, N, and O)-doped CuCl: A first-principles study

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Baozeng [Department of Applied Physics, Institute of Advanced Materials Physics, Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology, Faculty of Science, Tianjin University, Tianjin 300072 (China); Dong, Shengjie [Department of Physics, Tianjin Normal University, Tianjin 300387 (China); Wang, Jianchun [Department of Applied Physics, Institute of Advanced Materials Physics, Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology, Faculty of Science, Tianjin University, Tianjin 300072 (China); Zhao, Hui [Department of Physics, Tianjin Normal University, Tianjin 300387 (China); Wu, Ping, E-mail: pingwu@tju.edu.cn [Department of Applied Physics, Institute of Advanced Materials Physics, Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology, Faculty of Science, Tianjin University, Tianjin 300072 (China)

    2014-08-14

    Based on density functional calculations within both standard generalized gradient approximation and plus on-site Coulomb interactions approaches, we have investigated the electronic structure and magnetic properties of the first-row element-doped CuCl semiconductors. The electronic correlations in both 2p and 3d orbitals are enhanced by adding the on-site Coulomb repulsion (Hubbard U and Hund exchange J). After a comparative study, we find that, for both standard and beyond approaches, B-doped CuCl is a half-metallic magnet with majority-spin impurity bands touching the Fermi level, C-doped CuCl is a magnetic semiconductor, and N-doped CuCl is a half-metallic magnet with minority-spin impurity bands crossing the Fermi level. Nevertheless, for O-doped CuCl, it transforms from a nonmagnetic semiconductor to a half-metallic magnet with metallic up-spins by considering the correlation effects. The calculation shows that the enhanced electronic correlation not only corrects the error of band-gap, but also influences the magnetic ground state and the distribution of local magnetic moments. The location of impurity bands with different dopants was understood based on the elements' electronegativity and interaction between dopant and host atoms. Strong hybridization between the dopant's 2p states and the filled 3d orbitals of adjacent Cu yields the main contribution to magnetization. - Highlights: • The magnetic properties of the first-row element-doped CuCl are investigated. • The electronic correlations in both 2p and 3d orbitals are taken into account. • Strong p–d hybridization yields the main contributions to magnetization. • The enhanced electronic correlation may influence the magnetic ground state.

  8. ICP-AES法测定水中金属和非金属元素%Determination of Metals and Non-metals in Water by Inductively Coupl ed Plasma-Atomic Emission Spectrometry

    Institute of Scientific and Technical Information of China (English)

    刘桂华; 谢建滨

    2002-01-01

    目的为满足生活饮用水卫生规范中多元素分析的需要,建立准确快捷测定水中23种金属和非金属元素的方法. 方法用电感耦合等离子体发射光谱ICP-AES法,同时测定Ag、Al 、B、Ba、Be、Ca、Cd、Co、Cr、Cu、Fe、K、Li、Mg、Mn、Mo、Na、Ni、Si、Sr、Ti、V、Z n.结果方法快速、灵敏,各元素的检出限分别在0.000 02mg/L~0 .06mg/L之间;线性良好,线性相关系数均≥0.998;重现性好,不同浓度的变异系数为0. 37%~2.8%;准确度高,回收率在91%~116%之间,对标样GBW08607、GSBZ50009-88、C W82、GSBE50019-90测定,数值均在允许范围内,与原子吸收分光光度法对比,P均>0.0 5,表明两种方法检测结果之间无显著性差异. 结论本法实现多元素同时测定,准确可靠,极大地提高了工作效率,适用于水质分析.

  9. Inquire Into Tariff Analysis and Trade Problems of Non-metallic Mineral Products in China%我国非金属矿产品关税分析及其贸易问题探讨

    Institute of Scientific and Technical Information of China (English)

    陈甲斌; 殷俐娟

    2004-01-01

    我国非金属矿产品的进口关税历年总体上是下调的,然而在贸易上分析它的进出口价格却发现存在着很多隐含的贸易问题.为了解决这些问题和促进我国非金属矿产业的健康发展,本文就我国非金属矿产品贸易及其他相关方面的问题提出了一些建议.

  10. 切割丝用盘条非金属夹杂物对比分析%Contrast on non-metallic inclusions control in wire rods for saw wire

    Institute of Scientific and Technical Information of China (English)

    王昆鹏; 姜敏; 赵昊乾; 王新华; 王郢

    2016-01-01

    Inclusions in wire rods for saw wire produced in Kobe steel and a steel works of China were investigated by means of automatic analysis technology using Aspex Explorer. Inclusion size,number density,composition and morphol-ogy were studied systematically. The results show that the inclusions of wire rods from Kobe steel are in a low amount and the size is less than 5μm on cross section. There are two type inclusions in Kobe wire rods,namely,the SiO2 rich SiO2-MnO-Al2O3-(R2O,R=Na、K) type and the low melting point CaO-SiO2-Al2O3-MnO-(MgO) type,both of them are elongat-ed during rolling and are nearly harmless. Inclusions of wire rods from China are also classified into two types:SiO2-MnO-Al2O3 and CaO-SiO2-Al2O3-MnO-(MgO). The inclusions in wire rods from China are not only in lager amount but al-so in worse deformability. The inclusions more than 5μm in size were observed on cross section of wire rods from China. Chemical analysis shows w([Al]s) is 0.000 4%-0.000 6% and w(T[O]) is 0.001 2%-0.001 3% in Kobe wire rod while w([Al]s) is 0.000 4%-0.000 6%and w(T[O]) is 0.001 2%-0.001 3%in domestic ones.%借助Aspex Explorer全自动分析技术对日本神户制钢和国内某钢铁厂所产切割丝用盘条的夹杂物分析检测,详细讨论氧化物夹杂的尺寸、数量密度、成分以及形态.结果表明:神户所产盘条中夹杂物数量少、横截面尺寸均在5μm以下,存在两类夹杂物,即富SiO2的SiO2-MnO-Al2O3-(R2O,R=Na、K)系和低熔点的CaO-SiO2-Al2O3-MnO-(MgO)系夹杂物,两类夹杂物沿轧向均能很好变形,国内某厂所产盘条中夹杂物也分为两类:SiO2-MnO-Al2O3以及CaO-SiO2-Al2O3-MnO-(MgO),夹杂物数量多,变形差且检测到横截面尺寸5μm以上的夹杂物.盘条化学成分分析表明,神户盘条中w([Al]s)为0.000 4%~0.000 6%,w(T[O])为0.001 2%~0.001 3%,国内盘条w([Al]s)为0.000 5%~0.000 6%,w(T[O])为0.001 5%~0.001 6%.

  11. Aggregate and Mineral Resources, (Quarry Name) GPS locations of Non-Metallic Mining Sites and their stockpiles, Published in 2002, 1:24000 (1in=2000ft) scale, Lafayette County Land Records.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Aggregate and Mineral Resources dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Field Survey/GPS information as of 2002. It...

  12. Flexible Conformal Metal Rubber Sensors for Entry/Landing Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NanoSonic proposes to design and develop light-weight, low-modulus, and durable Metal Rubber sensors for aeroelastic analysis of inflatable/flexible entry, descent,...

  13. Advanced Metal Rubber Sensors for Hypersonic Decelerator Entry Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NanoSonic proposes to design and develop light-weight, low-modulus, and durable Metal Rubber™ sensors for aeroelastic analysis of Hypersonic Decelerator Entry...

  14. 非金属矿物材料在低碳经济进程中的定位与持续发展%The Orientation and Sustainable Development of Non-metallic Mineral Material During the Processing of a Low Carbon Economy(LCE)

    Institute of Scientific and Technical Information of China (English)

    万朴

    2010-01-01

    本文从低碳经济和低碳技术的全球发展形势,着重阐述低碳经济需要多轨并行互补发展--重视非金属矿与矿物材料产业节能属性的优势和贡献;矿物材料及非金属矿工业产业体系在发展广域低碳经济中具有衍生与辐射效应两个层面,以非金属矿工业发展理念和丰富的实例进行了论述,提出了应对低碳经济挑战的建议.

  15. Dynamic Study of the Electron Transfer Reaction for Non-metal Redox Couples of 0/1-Type%非金属氧化-还原对MO2/MO-2(M=N, S, Cl)的电子转移反应动力学

    Institute of Scientific and Technical Information of China (English)

    张冬菊; 庄炳游; 刘永军; 胡海泉; 刘成卜

    2001-01-01

    以Marcus-Hush电子转移理论为基础, 提出了用量子化学密度泛函方法研究自交换和异交换电子转移反应的理论方案. 在DFT B3LYP/6-311+G(2D)水平上研究了溶液中NO2/NO-2, SO2/SO-2和ClO2/ClO-2等3个氧化-还原对的自交换以及它们之间的6个交叉电子转移反应的动力学性质, 获得了与实验较为一致的结果.%A theoretical scheme is presented to study the dynamics of the self-exchange reactions and cross-reactions for the several bent triatomic species of 0/1-type (NO2/NO-2, SO2/SO-2, ClO2/ClO-2). The values of the inner-sphere reorganization energy and activation energy are calculated by using Nelson′s reoganization model with the results of density functional calculations. The values of the solvent reorganization energy are obtained by the dielectric continuum model of the Marcus Thery and by requesting a gas-phase molecular volume calculation in Gaussian 94 program package. The rate constants of the three self-exchange reactions (NO2/NO-2, SO2/SO-2, ClO2/ClO-2) and six cross-reactions (NO2/SO-2, NO-2/SO2, SO-2/ClO-2, SO2/ClO-2, NO2/ClO-2, NO-2/ClO2) are obtained by the relative and absolute Marcus-Hush theories. The theoretical results are compared with the experimental findings or the values from literature and better agreements are fornd.

  16. Tangible Asset Management In Real Sector Companies: A Parallel Between Industry Of Crude Oil Refining And Industry Of Refining Of Non Metallic Mineral In Colombia Gerenciamiento de activos tangibles en empresas del sector real: un paralelo entre industria de refinación de crudos e industria de refinación de minerales no metálicos en Colombia

    Directory of Open Access Journals (Sweden)

    John Jairo Forero Romero

    2012-08-01

    Full Text Available Enterprises around of the world are striving to understand and ensure that risks in utilities they govern are effectively managed while they must satisfy all expectations of their stakeholders. For this purpose there are now organisms and standardized management systems to manage financial risks, environmental hazards, industrial safety and occupational health risk. However, operational and reliability risks in the business lack an equivalent oversight body or an organizing framework through which enterprises can asses such risks , or define standards to which can be held accountable.The emergent understanding of asset management across all industry sectors has triggered a subsequent need for a standardized approach. This article identifies the key elements of asset management process and explains the benefits of the application of its elements with reference to two specific cases: the Barrancabermeja Refinery of Ecopetrol S.A. and  Sumicol S.A.Las empresas de todo el mundo se esfuerzan por comprender y asegurar que los riesgosen sus activos tangibles estén regidos bajo una administración eficaz y, a su vez, debenencargarse de cumplir con todas las expectativas de sus grupos de interés. Con estepropósito hoy en día existen organismos y sistemas de gestión estandarizados paraadministrar los riesgos financieros, ambientales, de seguridad de industrial y saludocupacional. Sin embargo, los riesgos operativos y de confiabilidad en el negocio hasta elmomento carecen de un órgano de supervisión equivalente, o un marco de organización através del cual las empresas pueden evaluar estos riesgos o definir las normas a las quepueden ser considerados responsables.El entendimiento emergente de la gestión efectiva de activos en todos los sectoresde la industria ha provocado una necesidad de un enfoque estandarizado. Este artículoidentifica los elementos clave del proceso de gestión de activos y explica los beneficiosde la aplicación de sus elementos tomando como referencia dos casos específicos: laRefinería de Barrancabermeja de Ecopetrol S.A. y Sumicol S.A.

  17. First Principles Calculations on Electronic Structures and Optical Absorption Properties of Non-metal Doped BiOCl%采用第一性原理研究非金属掺杂BiOCl的电子结构和光吸收性质

    Institute of Scientific and Technical Information of China (English)

    王艳; 张小超; 赵丽军; 赵晓霞; 史宝萍; 樊彩梅

    2014-01-01

    基于密度泛函理论的第一性原理分别研究了不同浓度Br和I掺杂BiOCl体系的能带结构、态密度、形成能和光学性质。研究结果表明,由于Br的4p和I的5p轨道作用, Br和I掺杂可在一定程度上降低BiOCl的禁带宽度,拓宽BiOCl的光吸收范围。 Br和I掺杂BiOCl的形成能计算结果表明, Br掺杂BiOCl的稳定性高于I掺杂体系。对于B, C, N, Si, P和S掺杂BiOCl体系,掺杂能级的形成主要由掺杂元素的np轨道贡献,使BiOCl吸收带边红移至可见光区。而S掺杂则位于价带顶位置,有效地降低了BiOCl禁带宽度,使BiOCl响应波长出现红移,且未形成中间能级,不易成为俘获陷阱,因此S掺杂将是一种提高BiOCl可见光光催化活性的改性方法。%The band structures, density of states, formation energies and optical properties of different con-centration Br and I doped BiOCl systems were investigated via first principles based on the density functional theory. The results show that the incorporation of Br 4p and I 5p orbitals can reduce the energy gap of BiOCl, and then broaden the photo-absorption range. The calculated formation energy indicates that Br-doped BiOCl system has higher stability than I-doped BiOCl at the same doping concentration. For B, C, N, Si, P, S doped BiOCl systems, the impurity energy levels are mainly contributed to the np states of doping elements, which can make the red-shift of photo-absorption band edge into visible light region. Especially, the impurity levels of S-doped BiOCl system located in the top of valence band are difficult to become recombination center of photon-generated carriers, which can result in the reduction of BiOCl band-gap and the red-shift of light-responding scope. The S-doped BiOCl system will be a preferable modification method to improve the photo-catalytic activity of BiOCl.

  18. Materials damaging and rupture - Volumes 1-2. General remarks, metallic materials. Non-metallic materials and biomaterials, assemblies and industrial problems;Endommagement et rupture des materiaux - Volumes 1-2. Generalites, materiaux metalliques. Materiaux non metalliques et biomateriaux, assemblages et problemes industriels

    Energy Technology Data Exchange (ETDEWEB)

    Clavel, M.; Bompard, P.

    2009-07-01

    The rupture and damaging of materials and structures is almost always and unwanted events which may have catastrophic consequences. Even if the mechanical failure causes can often be analyzed using a thorough knowledge of materials behaviour, the forecasting and prevention of failures remain difficult. While the macroscopic mechanical behaviour is often the result of average effects at the structure or microstructure scale, the damage is very often the result of the combination of load peaks, of localization effects and of microstructure defects. This book, presented in two volumes, takes stock of the state-of-the-art of the knowledge gained in the understanding and modelling of rupture and damaging phenomena of materials and structure, mostly of metallic type. It gives an outline of the available knowledge for other classes of materials (ceramics, biomaterials, geo-materials..) and for different types of applications (aeronautics, nuclear industry). Finally, it examines the delicate problem, but very important in practice, of the behaviour of assemblies. Content: Vol.1 - physical mechanisms of materials damaging and rupture; rupture mechanics; cyclic plasticity and fatigue crack growth; fatigue crack propagation; environment-induced cracking; contacts and surfaces. Vol.2 - glasses and ceramics; natural environments: soils and rocks; mechanical behaviour of biological solid materials: the human bone; contribution of simulation to the understanding of rupture mechanisms; assemblies damaging and rupture; industrial cases (behaviour of PWR pressure vessel steels, and thermal and mechanical stresses in turbojet engines). (J.S.)

  19. 废钢+铁水-50 t EAF-LF-VD流程GCr15轴承钢中的非金属夹杂物行为%Behavior of Non-Metallic Inclusions in GCr15 Bearing Steel Steelmaking by Scrap + Hot Metal-50 t EAF-LF-VD Flow Sheet

    Institute of Scientific and Technical Information of China (English)

    杨密平; 吴兵; 林腾昌; 安杰; 马传庆

    2014-01-01

    通过50 t EAF配加30 ~40 t铁水和12~16 t优质废钢,EBT无渣出钢,加150 ~ 200 kg钢芯铝预脱氧,LF用SiC扩散脱氧,控制精炼渣碱度4.0~5.9,VD前后软吹氩、连铸保护浇铸和电磁搅拌等工艺措施,GCr15轴承钢轧材中的氧含量为8×10-6 ~9×10-6.分析结果表明,LF前至VD后钢中夹杂物尺寸一般≤10 μm,最大尺寸40μm,大部分夹杂物尺寸为3~6 μm;LF前主要夹杂物为Al2O3,镁铝尖晶石,硫化物,Cr2O3,TiO2;VD前后为镁铝尖晶石,CaS和MgO.

  20. Determination of Accumulated Carbon on Non-Metallic Catalysts by Direct Combustion with Arc Induction Combustion Furnace and Gas Volumetry%电弧炉气体容量法测定非金属催化剂上的积碳

    Institute of Scientific and Technical Information of China (English)

    白正伟; 白炯; 常晓军

    2006-01-01

    在钢铁工业中,碳含量是区分钢种类的重要指标;在石油化工领域,催化剂上的积碳含量是影响催化剂活性的重要因素。常用的测定碳含量的方法有管式炉气体容量法、电弧炉气体容量法和高频炉红外光谱检测器法等,其原理都是将被测样品在高温下通氧燃烧,样品中的碳被转化成二氧化碳,然后用不同的方法进行检测。管式炉气体容量法比较便宜,

  1. On the Structure and Dissolution Properties of Poly(p-phenylene terephthalamide): Effect of Solvent Composition

    NARCIS (Netherlands)

    Westerhof, H.P.

    2009-01-01

    Poly-p-phenylenetherephthalamide (PpPTA) is a high performance, semi flexible polymer. Commercially it is mainly sold in the form of fibres under the trade names Twaron and Kevlar. The polymerization is performed in an amide(NMP)-salt(CaCl2) solution and afterwards spun into fibres from a sulphuric

  2. Carbon nanotube/biocompatible bola-amphiphile supramolecular biohybrid materials: preparation and their application in bacterial cell agglutination.

    Science.gov (United States)

    Yu, Guocan; Li, Jinying; Yu, Wei; Han, Chengyou; Mao, Zhengwei; Gao, Changyou; Huang, Feihe

    2013-11-26

    Supramolecular biohybrid materials were successfully constructed driven by non-covalent interactions between three biocompatible bolaform amphiphiles and single walled carbon nanotubes (SWNTs). The existence of galactoses in these supramolecular systems endowed the hybrid materials with interesting bio-function. By introducing the SWNTs as semi-flexible platforms, these supramolecular biohybrid materials display excellent agglutination ability for E. coli.

  3. Cd(II)-coordination polymers based on tetracarboxylic acid and diverse bis(imidazole) ligands: Synthesis, structural diversity and photoluminescence properties

    Science.gov (United States)

    Arıcı, Mürsel; Yeşilel, Okan Zafer; Taş, Murat

    2017-01-01

    Three new Cd(II)-coordination polymers, namely, {[Cd2(μ6-ao2btc)(μ-1,5-bipe)2]·2H2O}n (1), {[Cd2(μ6-ao2btc)(μ-1,4-bix)2]n·2DMF} (2) and {[Cd2(μ8-abtc)(μ-1,4-betix)]·DMF·H2O}n (3) (ao2btc=di-oxygenated form of 3,3‧,5,5‧-azobenzenetetracarboxylate, 1,5-bipe: 1,5-bis(imidazol-1yl)pentane, 1,4-bix=1,4-bis(imidazol-1ylmethyl)benzene, 1,4-betix=1,4-bis(2-ethylimidazol-1ylmethyl)benzene) were synthesized with 3,3‧,5,5‧-azobenzenetetracarboxylic acid and flexible, semi-flexible and semi-flexible substituted bis(imidazole) linkers. They were characterized by IR spectroscopy, elemental analysis, single-crystal X-ray diffraction, powder X-ray diffractions (PXRD) and thermal analyses (TG/DTA). Complexes 1-3 exhibited structural diversities depending on flexible, semi-flexible and semi-flexible substituted bis(imidazole) ligands. Complex 1 was 2D structure with 3,6L18 topology. Complex 2 had a 3D pillar-layered framework with the rare sqc27 topology. When semi-flexible substituted bis(imidazole) linker was used, 3D framework of complex 3 was obtained with the paddlewheel Cd2(CO2)4-type binuclear SBU. Moreover, thermal and photoluminescence properties of the complexes were determined in detailed.

  4. GROWTH AND MORPHOLOGY OF POLYMER-ACTIN COMPLEXES

    Institute of Scientific and Technical Information of China (English)

    Hyuck Joon Kwon; Kazuhiro Shikinaka; Akira Kakugo; Hidemitsu Furukawa; Yoshihito Osada; Jian Ping Gong

    2007-01-01

    F-actins are semi-flexible polyelectrolytes and can be assembled into large polymer-actin complex with polymorphism through electrostatic interaction with polycations. This study investigates the structural phase behavior and the growth of polymer-actin complexes in terms of its longitudinal and lateral sizes. Our results show that formation of polymer-actin complexes is cooperative, and morphology and growth of polymer-actin complexes depend on polycation species and concentrations of polycation and salt in a constant actin concentration. We found that the longitudinal growth and lateral growth of polymer-actin complexes are dominated by different factors. This induces the structural polymorphism of polymer-actin complexes. Major factors to influence the polymorphism of polymer-actin complexes in polyelectrolyte system have been discussed. Our results indicate that the semi-flexible polyelectrolyte nature of F-actins is important for controlling the morphology and growth of actin architectures in cell.

  5. Provide a Vessel to Conduct Observations and Deploy Sound Source for a Behavioral Response Study of Cetaceans off Southern California

    Science.gov (United States)

    2010-09-30

    offshore to include waters west of San Clemente and around San Nicolas and Catalina Islands • Cruising speed of at least 10 knots and range of 400 nmi of...place both regionally and from other BRS • Conduct semi-flexible field operations where RHIBs may base on ship, island , or coast in response to...just north of Santa Cruz Island RESULTS This was the first year of an anticipated 5-year study with this grant representing just one component

  6. Tumbling of a Brownian particle in an extensional flow

    CERN Document Server

    Plan, Emmanuel Lance Christopher VI Medillo

    2016-01-01

    The phenomenon of tumbling of microscopic objects is commonly associated with shear flows. We address the question of whether tumbling can also occur in stretching-dominated flows. To answer this, we study the dynamics of a semi-flexible trumbbell in a planar extensional velocity field. We show that the trumbbell undergoes a random tumbling-through-folding motion. The probability distribution of long tumbling times is exponential with a time scale exponentially increasing with the Weissenberg number.

  7. Models for twistable elastic polymers in Brownian dynamics, and their implementation for LAMMPS

    CERN Document Server

    Brackley, C A; Marenduzzo, D

    2014-01-01

    An elastic rod model for semi-flexible polymers is presented. Theory for a continuum rod is reviewed, and it is shown that a popular discretised model used in numerical simulations gives the correct continuum limit. Correlation functions relating to both bending and twisting of the rod are derived for both continuous and discrete cases, and results are compared with numerical simulations. Finally, two possible implementations of the discretised model in the multi-purpose molecular dynamics software package LAMMPS are described.

  8. Development of Multi-Scale Modeling Software for Entangled Soft Matter in Advanced Soldier Protection

    Science.gov (United States)

    2011-12-06

    entanglement theory to cross-linked systems 2.1.1 Bidisperse blends of linear polymers 2.1.2 Cross-linked polymer rheology predictions A progressive...Research Laboratory (ARL) has been developing cross-linked polymer gels as candidate materials to mimic human tissue. Such a mimetic is necessary to...including semi-flexibility) as input to the structure. In order to apply this theory to the problem at hand—predicting the rheology of cross- linked

  9. Method for Designing an Acoustic Array

    Science.gov (United States)

    2014-05-01

    30 and 32. Transduction material can be a continuous type of transducer material such as piezoelectric polymers. These include PVDF, 0-3 piezo ...rubber, and 1-3 piezo -composites, which are semi-flexible continuous sheets. As can be seen in the sectional view, foil electrodes 30 and 32 are...transduction technologies: PVDF piezoelectric polymer sheets, 0-3 piezo -rubber sheet, 1-3 piezo - composite n x m matrix, or Tonpilz transducer n x m elements

  10. Wrapping transition and wrapping-mediated interactions for discrete binding along an elastic filament: An exact solution

    Science.gov (United States)

    Dean, David S.; Hammant, Thomas C.; Horgan, Ronald R.; Naji, Ali; Podgornik, Rudolf

    2012-10-01

    The wrapping equilibria of one and two adsorbing cylinders are studied along a semi-flexible filament (polymer) due to the interplay between elastic rigidity and short-range adhesive energy between the cylinder and the filament. We show that statistical mechanics of the system can be solved exactly using a path integral formalism which gives access to the full effect of thermal fluctuations, going thus beyond the usual Gaussian approximations which take into account only the contributions from the minimal energy configuration and small fluctuations about this minimal energy solution. We obtain the free energy of the wrapping-unwrapping transition of the filament around the cylinders as well as the effective interaction between two wrapped cylinders due to thermal fluctuations of the elastic filament. A change of entropy due to wrapping of the filament around the adsorbing cylinders as they move closer together is identified as an additional source of interactions between them. Such entropic wrapping effects should be distinguished from the usual entropic configuration effects in semi-flexible polymers. Our results may be relevant to the problem of adsorption of oriented nano-rods on semi-flexible polymers.

  11. Epidermal electronics with advanced capabilities in near-field communication.

    Science.gov (United States)

    Kim, Jeonghyun; Banks, Anthony; Cheng, Huanyu; Xie, Zhaoqian; Xu, Sheng; Jang, Kyung-In; Lee, Jung Woo; Liu, Zhuangjian; Gutruf, Philipp; Huang, Xian; Wei, Pinghung; Liu, Fei; Li, Kan; Dalal, Mitul; Ghaffari, Roozbeh; Feng, Xue; Huang, Yonggang; Gupta, Sanjay; Paik, Ungyu; Rogers, John A

    2015-02-25

    Epidermal electronics with advanced capabilities in near field communications (NFC) are presented. The systems include stretchable coils and thinned NFC chips on thin, low modulus stretchable adhesives, to allow seamless, conformal contact with the skin and simultaneous capabilities for wireless interfaces to any standard, NFC-enabled smartphone, even under extreme deformation and after/during normal daily activities.

  12. Mesh词表词汇实用例句:“牙修复体-Dental Prosthesis”

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    例句 : Titanium and titanium alloys have biocompatibility, corrosion resistance, low cost and desirable physical and mechanical properties, such as low modulus, low thermal conductivity, high ductility, low density, and favorable microhardness, which make titanium and titanium alloys more attractive for dental prosthesis.

  13. Resistance of core materials against torsional forces on differently conditioned titanium posts

    NARCIS (Netherlands)

    Akisli, [No Value; Ozcan, M; Nergiz, [No Value

    2002-01-01

    Statement of problem. The separation of core materials from titanium posts, which have a low modulus of elasticity, has been identified as a problem in restorative dentistry. Purpose. This study evaluated the resistance to torsional forces of various core materials adapted to differently conditioned

  14. Hydrogels for an accommodating intraocular lens. An explorative study

    NARCIS (Netherlands)

    de Groot, JH; Spaans, CJ; van Calck, RV; van Beijma, FJ; Norrby, S; Pennings, AJ

    2003-01-01

    In this study it was investigated whether hydrogels could be used for an accommodating lens. The requirements of such a hydrogels are a low modulus, high refractive index, transparency, and strength. Since conventional hydrogels do not possess this combination of properties, a novel preparation meth

  15. INCREASE STRUCTURAL STRENGTH OF MARGANESE STEEL

    Directory of Open Access Journals (Sweden)

    L. N. Bunina

    2011-04-01

    Full Text Available The manganese steels are widely used in machinery construction. The influence of chemical composition and form of non-metallic inclusions on constructive strength of manganese steels is studied. The dependences between the nature of non-metallic inclusions and properties of steels are given.

  16. Evaluation of the Impact of Fatty Acid Methyl Ester (FAME) Contamination on the Thermal Stability of Jet A

    Science.gov (United States)

    2013-11-01

    Carbon-Type Amorphous Material with Metalic and Non-Metalic Constituents Analysis of “Brown Goo” HP Pump Filter Elt . Line Intensity (c/s) Error...Pump Filter FINDING Carbon-containing amorphous material with metals and non-metals contamination Elt . Line Intensity (c/s) Error 2-sig Conc Units...6 4.1 Materials

  17. Update on the management of dentoalveolar trauma.

    Science.gov (United States)

    MacLeod, Stephen P R; Rudd, Travis C

    2012-08-01

    Dentoalveolar injuries are the most common type of facial injury and are often associated with concomitant facial fractures. These injuries may initially be seen by surgeons who do not have formal dental training. This article reviews the assessment and management of dentoalveolar fractures. Semi-flexible splinting of traumatized teeth for shorter periods of time than previously suggested is associated with better long-term outcomes. The use of dental implants to replace teeth lost to trauma is a predictable restorative option. Surgeons need to be aware that dentoalveolar injuries may be a marker for other injuries. Prompt relocation and splinting of displaced teeth is associated with better outcomes.

  18. Development of high temperature silicone adhesive formulations for thermal protection system applications

    Science.gov (United States)

    Hockridge, R. R.

    1973-01-01

    Trade-off studies and screening evaluations were made of commercial polymers and silicone foam sheet stock. A low modulus, low density 0.26 gm/cc modification was developed of the GE-RESD PD-200 system based upon GE RTV-560 silicone polymer. The bond system modification was initially characterized for mechanical and thermal properties, evaluated for application methods, and its capability demonstrated as a strain arrestor bond system.

  19. Polyurethane elastomers as maxillofacial prosthetic materials.

    Science.gov (United States)

    Goldberg, A J; Craig, R G; Filisko, F E

    1978-04-01

    A series of polyurethane elastomers based on an aliphatic diisocyanate and a polyether macroglycol was polymerized with various cross-link densities and OH/NCO ratios. Stoichiometries yielding between 8,600 and 12,900 gm/mole/crosslink and an OH/NCO ratio of 1.1 resulted in polymers with the low modulus, yet high strength and elongation necessary for maxillofacial applications.

  20. Design optimization of a radial functionally graded dental implant.

    Science.gov (United States)

    Ichim, Paul I; Hu, Xiaozhi; Bazen, Jennifer J; Yi, Wei

    2016-01-01

    In this work, we use FEA to test the hypothesis that a low-modulus coating of a cylindrical zirconia dental implant would reduce the stresses in the peri-implant bone and we use design optimization and the rule of mixture to estimate the elastic modulus and the porosity of the coating that provides optimal stress shielding. We show that a low-modulus coating of a dental implant significantly reduces the maximum stresses in the peri-implant bone without affecting the average stresses thus creating a potentially favorable biomechanical environment. Our results suggest that a resilient coating is capable of reducing the maximum compressive and tensile stresses in the peri-implant bone by up to 50% and the average stresses in the peri-implant bone by up to 15%. We further show that a transitional gradient between the high-modulus core and the low-modulus coating is not necessary and for a considered zirconia/HA composite the optimal thickness of the coating is 100 µ with its optimal elastic at the lowest value considered of 45 GPa. © 2015 Wiley Periodicals, Inc.

  1. Development of new metallic alloys for biomedical applications.

    Science.gov (United States)

    Niinomi, Mitsuo; Nakai, Masaaki; Hieda, Junko

    2012-11-01

    New low modulus β-type titanium alloys for biomedical applications are still currently being developed. Strong and enduring β-type titanium alloy with a low Young's modulus are being investigated. A low modulus has been proved to be effective in inhibiting bone atrophy, leading to good bone remodeling in a bone fracture model in the rabbit tibia. Very recently β-type titanium alloys with a self-tunable modulus have been proposed for the construction of removable implants. Nickel-free low modulus β-type titanium alloys showing shape memory and super elastic behavior are also currently being developed. Nickel-free stainless steel and cobalt-chromium alloys for biomedical applications are receiving attention as well. Newly developed zirconium-based alloys for biomedical applications are proving very interesting. Magnesium-based or iron-based biodegradable biomaterials are under development. Further, tantalum, and niobium and its alloys are being investigated for biomedical applications. The development of new metallic alloys for biomedical applications is described in this paper.

  2. Effect of thermo-mechanical treatment on mechanical and elastic properties of Ti–36Nb–5Zr alloy

    Directory of Open Access Journals (Sweden)

    Qingkun Meng

    2015-06-01

    Full Text Available The evolutions of phase constitutions and mechanical properties of a β-phaseTi–36Nb–5Zr (wt% alloy during thermo-mechanical treatment were investigated. The alloy consisted of dual (β+α″ phase and exhibited a double yielding phenomenon in solution treated state. After cold rolling and subsequent annealing at 698 K for 20 min, an excellent combination of high strength (833 MPa and low modulus (46 GPa was obtained. The high strength can be attributed to high density of dislocations, nanosized α phase and grain refinement. On the other hand, the low Young׳s modulus originates from the suppression of chemical stabilization of β phase during annealing, which guarantees the low β-phase stability. Furthermore, the single-crystal elastic constants of the annealed Ti–36Nb–5Zr alloy were extracted from polycrystalline alloy using an in-situ synchrotron X-ray technique. The results indicated that the low shear modulus C44 contributes to the low Young׳s modulus for the Ti–36Nb–5Zr alloy, suggesting that reducing C44 through thermo-mechanical treatment might be an efficient approach to realize low Young׳s modulus in β-phase Ti alloys. The results achieved in this study could be helpful to elucidate the origin of low modulus and sheds light on developing novel biomedical Ti alloys with both low modulus and high strength.

  3. Effect of thermo-mechanical treatment on mechanical and elastic properties of Ti-36Nb-5Zr alloy

    Institute of Scientific and Technical Information of China (English)

    Qingkun Meng; Qing Liu; Shun Guo; Yongqi Zhu; Xinqing Zhao

    2015-01-01

    The evolutions of phase constitutions and mechanical properties of aβ-phaseTi–36Nb–5Zr (wt%) alloy during thermo-mechanical treatment were investigated. The alloy consisted of dual (βþα″) phase and exhibited a double yielding phenomenon in solution treated state. After cold rolling and subsequent annealing at 698 K for 20 min, an excellent combination of high strength (833 MPa) and low modulus (46 GPa) was obtained. The high strength can be attributed to high density of dislocations, nanosizedαphase and grain refinement. On the other hand, the low Young's modulus originates from the suppression of chemical stabilization of β phase during annealing, which guarantees the low β-phase stability. Furthermore, the single-crystal elastic constants of the annealed Ti–36Nb–5Zr alloy were extracted from polycrystalline alloy using an in-situ synchrotron X-ray technique. The results indicated that the low shear modulus C44 contributes to the low Young's modulus for the Ti–36Nb–5Zr alloy, suggesting that reducing C44 through thermo-mechanical treatment might be an efficient approach to realize low Young's modulus in β-phase Ti alloys. The results achieved in this study could be helpful to elucidate the origin of low modulus and sheds light on developing novel biomedical Ti alloys with both low modulus and high strength.

  4. Practical Efficiency of Photovoltaic Panel Used for Solar Vehicles

    Science.gov (United States)

    Koyuncu, T.

    2017-08-01

    In this experimental investigation, practical efficiency of semi-flexible monocrystalline silicon solar panel used for a solar powered car called “Firat Force” and a solar powered minibus called “Commagene” was determined. Firat Force has 6 solar PV modules, a maintenance free long life gel battery pack, a regenerative brushless DC electric motor and Commagene has 12 solar PV modules, a maintenance free long life gel battery pack, a regenerative brushless DC electric motor. In addition, both solar vehicles have MPPT (Maximum power point tracker), ECU (Electronic control unit), differential, instrument panel, steering system, brake system, brake and gas pedals, mechanical equipments, chassis and frame. These two solar vehicles were used for people transportation in Adiyaman city, Turkey, during one year (June 2010-May 2011) of test. As a result, the practical efficiency of semi-flexible monocrystalline silicon solar panel used for Firat Force and Commagene was determined as 13 % in despite of efficiency value of 18% (at 1000 W/m2 and 25 °C ) given by the producer company. Besides, the total efficiency (from PV panels to vehicle wheel) of the system was also defined as 9%.

  5. Effect of artificial insemination protocol and dose of frozen/thawed stallion semen on pregnancy results in mares.

    Science.gov (United States)

    Govaere, J L J; Hoogewijs, M K; De Schauwer, C; De Vliegher, S; Van Soom, A; Duchateau, L; de Kruif, A

    2014-06-01

    Deep intra-uterine insemination is commonly accepted as a routine procedure for artificial insemination in horses. The motives and principles of deep insemination are well described, but the equipment used may differ. In this trial, the efficiency of two different insemination pipettes for deep intra-uterine insemination in the mare was compared with insemination into the uterine body using commercially available frozen-thawed semen of two stallions of proven fertility. These inseminations were performed using two different doses. The semi-flexible Minitube pipette was compared with a newly designed insemination device with a more flexible telescopic insemination catheter (Ghent device). The semi-flexible Minitube pipette performed better than the newly designed insemination device with respect to pregnancy outcome (p = 0.008). The superiority of deep horn insemination over uterine body insemination was reflected by the better pregnancy rates obtained after deep insemination using the same low doses (30.6% better pregnancy rates) (p = 0.0123).

  6. Tuning the Mechanical Properties of Polymer Nanocomposites Filled with Grafted Nanoparticles by Varying the Grafted Chain Length and Flexibility

    Directory of Open Access Journals (Sweden)

    Zixuan Wang

    2016-08-01

    Full Text Available By employing coarse-grained molecular dynamics simulation, we simulate the spatial organization of the polymer-grafted nanoparticles (NPs in homopolymer matrix and the resulting mechanical performance, by particularly regulating the grafted chain length and flexibility. The morphologies ranging from the agglomerate, cylinder, sheet, and string to full dispersion are observed, by gradually increasing the grafted chain length. The radial distribution function and the total interaction energy between NPs are calculated. Meanwhile, the stress–strain behavior of each morphology and the morphological evolution during the uniaxial tension are simulated. In particular, the sheet structure exhibits the best mechanical reinforcement compared to other morphologies. In addition, the change of the grafted chain flexibility to semi-flexibility leads to the variation of the morphology. We also find that at long grafted chain length, the stress–strain behavior of the system with the semi-flexible grafted chain begins to exceed that of the system with the flexible grafted chain, attributed to the physical inter-locking interaction between the matrix and grafted polymer chains. A similar transition trend is as well found in the presence of the interfacial chemical couplings between grafted and matrix polymer chains. In general, this work is expected to help to design and fabricate high performance polymer nanocomposites filled with grafted NPs with excellent and controllable mechanical properties.

  7. [Penetrating head and brain injuries with nonmetal foreign bodies].

    Science.gov (United States)

    Potapov, A A; Okhlopkov, V A; Latyshev, Ya A; Serova, N K; Eolchiyan, S A

    2014-01-01

    Penetrating brain injuries (PBI) are common in neurosurgical practice. Most of them are civil or war-time missile and blast injuries. This type of trauma is widely presented in neurosurgical publication, textbooks and clinical evidence-based guidelines. At the same time, PBI by non-metallic foreign bodies are very rare. All the data are limited to case reports and small series of cases. Moreover, there are no clinical consideration on diagnosis, treatment, complication, outcome and prognosis of PBI by non-metallic penetrating brain injuries. In this review all the data are summarized to provide recommendations on the diagnosis and treatment of PBI by non-metallic foreign bodies.

  8. An energy-dispersive X-ray analysis and SEM study of debris remaining on endodontic instruments after ultrasonic cleaning and autoclave sterilization.

    Science.gov (United States)

    Parirokh, Masoud; Asgary, Saeed; Eghbal, Mohammad Jafar

    2005-08-01

    This study was carried out to investigate metallic and non-metallic debris remaining on endodontic files after ultrasonic cleaning and autoclave processing. Forty-eight unused rotary and hand endodontic files, including eight different brands, were tested. Instruments were cleaned with ultrasound, autoclaved and before and after each step were observed by scanning electron microscopy (SEM). Adherent debris was analysed by energy-dispersive X-ray analysis (EDXA). All of the instruments before ultrasound cleaning were contaminated with metallic and non-metallic debris. Although most non-metallic debris was removed by ultrasonic cleaning, most of the metallic debris remained even after the final step of sterilization.

  9. A finite element thermal analysis of various dowel and core materials

    Directory of Open Access Journals (Sweden)

    Shanti Varghese

    2012-01-01

    Conclusion: Non-metallic dowel and core materials such as fibre reinforced composite dowels (FRC generate greater stress than metallic dowel and core materials. This emphasized the preferable use of the metallic dowel and core materials in the oral environment.

  10. 75 FR 65453 - Certain Hot-Rolled Flat-Rolled Carbon Quality Steel Flat Products From Brazil: Notice of...

    Science.gov (United States)

    2010-10-25

    ..., varnished, or coated with plastics or other non-metallic substances, in coils (whether or not in..., SAE grade 1050, in coils, with an inclusion rating of 1.0 maximum per ASTM E 45, Method A, with...

  11. Geothermal systems materials: a workshop/symposium

    Energy Technology Data Exchange (ETDEWEB)

    1978-01-01

    Sixteen papers are included. A separate abstract was prepared for each. Summaries of workshops on the following topics are also included in the report: non-metallic materials, corrosion, materials selection, fluid chemistry, and failure analysis. (MHR)

  12. Benzidine Dyes Action Plan

    Science.gov (United States)

    This Action Plan addresses the use of benzidine-based dyes and benzidine congener-based dyes, both metalized and non-metalized, in products that would result in consumer exposure, such as for use to color textiles.

  13. The I-Xe System in the IVA Iron Meteorite Steinbach

    Science.gov (United States)

    Pravdivtseva, O.; Meshik, A.; Hohenberg, C. M.

    2013-09-01

    Non-metallic phases from IVA Steinbach were separated and identified to be troilite, chromite, tridymite, and clino- and orthopyroxene. Xenon isotopic compositions are measured to identify possible iodine carrier phases suitable for the I-Xe dating.

  14. Antenna Pattern Range (APR)

    Data.gov (United States)

    Federal Laboratory Consortium — TheAntenna Pattern Range (APR)features a non-metallic arch with a trolley to move the transmit antenna from the horizon to zenith. At the center of the ground plane,...

  15. Terahertz Quantum Cascade Laser Based 3D Imaging Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The NASA Constellation program has a need to non-destructively test (NDT) non-metallic materials (foams, Shuttle Tile, Avcoat, etc) for defects such as delaminations...

  16. Three-Dimensional Backscatter X-Ray Imaging System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The NASA application requires a system that can generate 3D images of non-metallic material when access is limited to one side of the material. The objective of this...

  17. The Use of Barium and Calcium Alloys in the Ladle Furnace Treatment of Selected Grades of Continuously Cast Steels

    Directory of Open Access Journals (Sweden)

    Derda W.

    2015-04-01

    Full Text Available The subject of the paper are the results of laboratory and industrial investigations into the use of Si - Ca - Ba alloys for modifying non-metallic inclusions. Based on laboratory tests, the morphology and chemical composition of non-metallic inclusions in carbon steel were examined before and after refining with the use of the above-mentioned alloy as a refining addition. In particular tests, variable additions of the alloy were used at a constant refining time and temperature.

  18. Toughness of Bulk Metallic Glasses

    Directory of Open Access Journals (Sweden)

    Shantanu V. Madge

    2015-07-01

    Full Text Available Bulk metallic glasses (BMGs have desirable properties like high strength and low modulus, but their toughness can show much variation, depending on the kind of test as well as alloy chemistry. This article reviews the type of toughness tests commonly performed and the factors influencing the data obtained. It appears that even the less-tough metallic glasses are tougher than oxide glasses. The current theories describing the links between toughness and material parameters, including elastic constants and alloy chemistry (ordering in the glass, are discussed. Based on the current literature, a few important issues for further work are identified.

  19. Surface modification of titanium and titanium alloys by ion implantation.

    Science.gov (United States)

    Rautray, Tapash R; Narayanan, R; Kwon, Tae-Yub; Kim, Kyo-Han

    2010-05-01

    Titanium and titanium alloys are widely used in biomedical devices and components, especially as hard tissue replacements as well as in cardiac and cardiovascular applications, because of their desirable properties, such as relatively low modulus, good fatigue strength, formability, machinability, corrosion resistance, and biocompatibility. However, titanium and its alloys cannot meet all of the clinical requirements. Therefore, to improve the biological, chemical, and mechanical properties, surface modification is often performed. In view of this, the current review casts new light on surface modification of titanium and titanium alloys by ion beam implantation.

  20. Corrosion-resistant coating development

    Energy Technology Data Exchange (ETDEWEB)

    Stinton, D.P.; Kupp, D.M.; Martin, R.L. [Oak Ridge National Lab., TN (United States)

    1997-12-01

    SiC-based heat exchangers have been identified as the prime candidate material for use as heat exchangers in advanced combined cycle power plants. Unfortunately, hot corrosion of the SiC-based materials created by alkali metal salts present in the combustion gases dictates the need for corrosion-resistant coatings. The well-documented corrosion resistance of CS-50 combined with its low (and tailorable) coefficient of thermal expansion and low modulus makes CS-50 an ideal candidate for this application. Coatings produced by gelcasting and traditional particulate processing have been evaluated.

  1. Investigation of Test Methods, Material Properties, and Processes for Solar Cell Encapsulants

    Science.gov (United States)

    Willis, P. B.; Baum, B.

    1979-01-01

    The reformulation of a commercial grade of ethylene/vinyl acetate copolymer for use as a pottant in solar cell module manufacture was investigated. Potentially successful formulations were prepared by compounding the raw polymer with antioxidants, ultraviolet absorbers and crosslinking agents to yield stabilized and curable compositions. The resulting elastomer was found to offer low cost (approximately $0.80/lb.), low temperature processability, high transparency (91% transmission), and low modulus. Cured specimens of the final formulation endured 4000 hours of fluorescent sunlamp radiation without change which indicates excellent stability.

  2. Preparation of A New Type of Stress-absorbed Material

    Institute of Scientific and Technical Information of China (English)

    WU Shao-peng; YANG Tao; YUAN Hai-qing

    2004-01-01

    Neoprene latex modified emulsified bitumen and fine aggregate are used to prepare a new type of stress-absorbed material, which has strong ability of anti-reflective cracking on asphalt concrete over layer-constructed upon a semi-rigid type base course or cement concrete pavement block. Experimental results demonstrate the stress-absorbed material have excellent mechanical properties including a low modulus of elasticity, high ultimate tensile stress and strain, and a strong distortion ability. Stress concentration in asphalt over layer originated by temperature changes and traffic loads can be alleviated.

  3. Solid propellant motor

    Science.gov (United States)

    Shafer, J. I.; Marsh, H. E., Jr. (Inventor)

    1978-01-01

    A case bonded end burning solid propellant rocket motor is described. A propellant with sufficiently low modulus to avoid chamber buckling on cooling from cure and sufficiently high elongation to sustain the stresses induced without cracking is used. The propellant is zone cured within the motor case at high pressures equal to or approaching the pressure at which the motor will operate during combustion. A solid propellant motor with a burning time long enough that its spacecraft would be limited to a maximum acceleration of less than 1 g is provided by one version of the case bonded end burning solid propellant motor of the invention.

  4. Oxide coating development

    Energy Technology Data Exchange (ETDEWEB)

    Stinton, D.P.

    1995-06-01

    Monolithic SiC heat exchangers and fiber-reinforced SiC-matrix composite heat exchangers and filters are susceptible to corrosion by alkali metals at elevated temperatures. Protective coatings are currently being developed to isolate the SiC materials from the corrodants. Unfortunately, these coatings typically crack and spall when applied to SiC substrates. The purpose of this task is to determine the feasibility of using a compliant material between the protective coating and the substrate. The low-modulus compliant layer could absorb stresses and eliminate cracking and spalling of the protective coatings.

  5. Modeling the behavior of an earthquake base-isolated building.

    Energy Technology Data Exchange (ETDEWEB)

    Coveney, V. A.; Jamil, S.; Johnson, D. E.; Kulak, R. F.; Uras, R. A.

    1997-11-26

    Protecting a structure against earthquake excitation by supporting it on laminated elastomeric bearings has become a widely accepted practice. The ability to perform accurate simulation of the system, including FEA of the bearings, would be desirable--especially for key installations. In this paper attempts to model the behavior of elastomeric earthquake bearings are outlined. Attention is focused on modeling highly-filled, low-modulus, high-damping elastomeric isolator systems; comparisons are made between standard triboelastic solid model predictions and test results.

  6. Oxidation-resistant interfacial coatings for continuous fiber ceramic composites

    Energy Technology Data Exchange (ETDEWEB)

    Stinton, D.P.; Besmann, T.M.; Bleier, A. [Oak Ridge National Lab., TN (United States); Shanmugham, S.; Liaw, P.K. [Univ. of Tennessee, Knoxville, TN (United States)

    1995-08-01

    Continuous fiber ceramic composites mechanical behavior are influenced by the bonding characteristics between the fiber and the matrix. Finite modeling studies suggest that a low-modulus interfacial coating material will be effective in reducing the residual thermal stresses that are generated upon cooling from processing temperatures. Nicalon{trademark}/SiC composites with carbon, alumina and mullite interfacial coatings were fabricated with the SiC matrix deposited using a forced-flow, thermal gradient chemical vapor infiltration process. Composites with mullite interfacial coatings exhibited considerable fiber pull-out even after oxidation and have potential as a composite system.

  7. On the occurrence of metallic character in the periodic table of the chemical elements.

    Science.gov (United States)

    Hensel, Friedrich; Slocombe, Daniel R; Edwards, Peter P

    2015-03-13

    The classification of a chemical element as either 'metal' or 'non-metal' continues to form the basis of an instantly recognizable, universal representation of the periodic table (Mendeleeff D. 1905 The principles of chemistry, vol. II, p. 23; Poliakoff M. & Tang S. 2015 Phil. Trans. R. Soc. A 373: , 20140211). Here, we review major, pre-quantum-mechanical innovations (Goldhammer DA. 1913 Dispersion und Absorption des Lichtes; Herzfeld KF. 1927 Phys. Rev. 29: , 701-705) that allow an understanding of the metallic or non-metallic status of the chemical elements under both ambient and extreme conditions. A special emphasis will be placed on recent experimental advances that investigate how the electronic properties of chemical elements vary with temperature and density, and how this invariably relates to a changing status of the chemical elements. Thus, the prototypical non-metals, hydrogen and helium, becomes metallic at high densities; and the acknowledged metals, mercury, rubidium and caesium, transform into their non-metallic forms at low elemental densities. This reflects the fundamental fact that, at temperatures above the absolute zero of temperature, there is therefore no clear dividing line between metals and non-metals. Our conventional demarcation of chemical elements as metals or non-metals within the periodic table is of course governed by our experience of the nature of the elements under ambient conditions. Examination of these other situations helps us to examine the exact divisions of the chemical elements into metals and non-metals (Mendeleeff D. 1905 The principles of chemistry, vol. II, p. 23). © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  8. Persistence of strain in motor-filament assemblies

    CERN Document Server

    Gopinath, Arvind; Mahadevan, L

    2015-01-01

    Crosslinked semi-flexible and flexible filaments that are actively deformed by molecular motors occur in various natural settings, such as the ordered eukaryotic flagellum, and the disordered cytoskeleton. The deformation of these composite systems is driven by active motor forces and resisted by passive filament elasticity, and structural constraints due to permanent cross-links. Using a mean field theory for a one-dimensional ordered system, we show that the combination of motor activity and finite filament extensibility yields a characteristic persistence length scale over which active strain decays. This decay length is set by the ability of motors to respond to combination of the weak extensional elasticity, passive shear resistance and the viscoelastic properties of the motor assembly, and generalizes the notion of persistence in purely thermal filaments to active systems.

  9. In silico modeling of the rheological properties of covalently crosslinked collagen triple helices

    CERN Document Server

    Head, David A; Russell, Stephen J; Wood, David J

    2016-01-01

    Biomimetic hydrogels based on natural polymers are a promising class of biomaterial, mimicking the natural extra-cellular matrix of biological tissues and providing cues for cell attachment, proliferation and differentiation. With a view to providing an upstream method to guide subsequent experimental design, the aim of this study was to introduce a mathematical model that described the rheological properties of a hydrogel system based on covalently crosslinked collagen triple helices. In light of their organization, such gels exhibit limited collagen bundling that cannot be described by existing fibril network models. The model presented here treats collagen triple helices as discrete semi-flexible polymers, permits full access to metrics for network microstructure, and should provide a comprehensive understanding of the parameter space associated with the development of such multi-functional materials. Triple helical hydrogel networks were experimentally obtained via reaction of type I collagen with both ar...

  10. Stretchable silicon nanoribbon electronics for skin prosthesis.

    Science.gov (United States)

    Kim, Jaemin; Lee, Mincheol; Shim, Hyung Joon; Ghaffari, Roozbeh; Cho, Hye Rim; Son, Donghee; Jung, Yei Hwan; Soh, Min; Choi, Changsoon; Jung, Sungmook; Chu, Kon; Jeon, Daejong; Lee, Soon-Tae; Kim, Ji Hoon; Choi, Seung Hong; Hyeon, Taeghwan; Kim, Dae-Hyeong

    2014-12-09

    Sensory receptors in human skin transmit a wealth of tactile and thermal signals from external environments to the brain. Despite advances in our understanding of mechano- and thermosensation, replication of these unique sensory characteristics in artificial skin and prosthetics remains challenging. Recent efforts to develop smart prosthetics, which exploit rigid and/or semi-flexible pressure, strain and temperature sensors, provide promising routes for sensor-laden bionic systems, but with limited stretchability, detection range and spatio-temporal resolution. Here we demonstrate smart prosthetic skin instrumented with ultrathin, single crystalline silicon nanoribbon strain, pressure and temperature sensor arrays as well as associated humidity sensors, electroresistive heaters and stretchable multi-electrode arrays for nerve stimulation. This collection of stretchable sensors and actuators facilitate highly localized mechanical and thermal skin-like perception in response to external stimuli, thus providing unique opportunities for emerging classes of prostheses and peripheral nervous system interface technologies.

  11. How a single stretched polymer responds coherently to a minute oscillation in fluctuating environments: An entropic stochastic resonance

    CERN Document Server

    Kim, Won Kyu; 10.1063/1.4746118

    2012-01-01

    Within the cell, biopolymers are often situated in constrained, fluid environments, e.g., cytoskeletal networks, stretched DNAs in chromatin. It is of paramount importance to understand quantitatively how they, utilizing their flexibility, optimally respond to a minute signal, which is, in general, temporally fluctuating far away from equilibrium. To this end, we analytically study viscoelastic response and associated stochastic resonance in a stretched single semi-flexible chain to an oscillatory force or electric field. Including hydrodynamic interactions between chain segments, we evaluate dynamics of the polymer extension in coherent response to the force or field. We find power amplification factor of the response at a noise-strength (temperature) can attain the maximum that grows as the chain length increases, indicative of an entropic stochastic resonance (ESR). In particular for a charged chain under an electric field, we find that the maximum also occurs at an optimal chain length, a new feature of E...

  12. Dynamic analysis of polymeric fluid in shear flow for dumbbell model with internal viscosity

    Institute of Scientific and Technical Information of China (English)

    杨晓东; R.V.N.MELNIK

    2008-01-01

    The dynamic analysis of semi-flexible polymers,such as DNA molecules,is an important multiscale problem with a wide range of applications in science and bioengineering.In this contribution,a dumbbell model with internal viscosity was studied in steady shear flows of polymeric fluid.The tensors with moments other than second moment were approximated in the terms of second moment tensor.Then,the nonlinear algebraic equation of the second moment conformation tensor was calculated in closed form.Finally,substituting the resulting conformation tensor into the Kramers equation of Hookean spring force,the constitutive equations were obtained.The shear material properties were discussed for different internal viscosities and compared with the results of Brownian dynamics simulation.

  13. Effects of Using Silica Fume and Polycarboxylate-Type Superplasticizer on Physical Properties of Cementitious Grout Mixtures for Semiflexible Pavement Surfacing

    Science.gov (United States)

    Karim, Mohamed Rehan; Mahmud, Hilmi; Mashaan, Nuha S.; Katman, Herdayati; Husain, Nadiah Md

    2014-01-01

    Semi-flexible pavement surfacing is a composite pavement that utilizes the porous pavement structure of the flexible bituminous pavement, which is subsequently grouted with appropriate cementitious materials. This study aims to investigate the compressive strength, flexural strength, and workability performance of cementitious grout. The grout mixtures are designed to achieve high strength and maintain flow properties in order to allow the cement slurries to infiltrate easily through unfilled compacted skeletons. A paired-sample t-test was carried out to find out whether water/cement ratio, SP percentages, and use of silica fume influence the cementitious grout performance. The findings showed that the replacement of 5% silica fume with an adequate amount of superplasticizer and water/cement ratio was beneficial in improving the properties of the cementitious grout. PMID:24526911

  14. Facilitated diffusion on mobile DNA: configurational traps and sequence heterogeneity

    CERN Document Server

    Brackley, C A; Marenduzzo, D; 10.1103/PhysRevLett.109.168103

    2012-01-01

    We present Brownian dynamics simulations of the facilitated diffusion of a protein, modelled as a sphere with a binding site on its surface, along DNA, modelled as a semi-flexible polymer. We consider both the effect of DNA organisation in 3D, and of sequence heterogeneity. We find that in a network of DNA loops, as are thought to be present in bacterial DNA, the search process is very sensitive to the spatial location of the target within such loops. Therefore, specific genes might be repressed or promoted by changing the local topology of the genome. On the other hand, sequence heterogeneity creates traps which normally slow down facilitated diffusion. When suitably positioned, though, these traps can, surprisingly, render the search process much more efficient.

  15. Stretchable silicon nanoribbon electronics for skin prosthesis

    Science.gov (United States)

    Kim, Jaemin; Lee, Mincheol; Shim, Hyung Joon; Ghaffari, Roozbeh; Cho, Hye Rim; Son, Donghee; Jung, Yei Hwan; Soh, Min; Choi, Changsoon; Jung, Sungmook; Chu, Kon; Jeon, Daejong; Lee, Soon-Tae; Kim, Ji Hoon; Choi, Seung Hong; Hyeon, Taeghwan; Kim, Dae-Hyeong

    2014-12-01

    Sensory receptors in human skin transmit a wealth of tactile and thermal signals from external environments to the brain. Despite advances in our understanding of mechano- and thermosensation, replication of these unique sensory characteristics in artificial skin and prosthetics remains challenging. Recent efforts to develop smart prosthetics, which exploit rigid and/or semi-flexible pressure, strain and temperature sensors, provide promising routes for sensor-laden bionic systems, but with limited stretchability, detection range and spatio-temporal resolution. Here we demonstrate smart prosthetic skin instrumented with ultrathin, single crystalline silicon nanoribbon strain, pressure and temperature sensor arrays as well as associated humidity sensors, electroresistive heaters and stretchable multi-electrode arrays for nerve stimulation. This collection of stretchable sensors and actuators facilitate highly localized mechanical and thermal skin-like perception in response to external stimuli, thus providing unique opportunities for emerging classes of prostheses and peripheral nervous system interface technologies.

  16. Operation Pillar of Defence and the 2013 Israeli Elections: Defensive or Provocative Intervention?

    Directory of Open Access Journals (Sweden)

    Philippe Orenes

    2014-06-01

    Full Text Available 'Based on the research on the psychological and political effects of terrorism, this paper focuses on the possible use of provocative counter-terrorism operations in order to influence the outcome of elections. Exploring the case of the Israeli Operation Pillar of Defence, that occurred from 14 November, 2012 to 21 November, the study resorts to qualitative and quantitative methods in a semi-flexible design with a view to exploring whether this operation, and the major escalation it took part in, was necessary and proportionate. The findings are that, in light of the broader context and Israeli experience with counter-terrorism responses, the political exploitation of the psychological effects of this crisis may have been a major motive in the decision to launch this operation.' ' '

  17. Generalized elastic model yields a fractional Langevin equation description.

    Science.gov (United States)

    Taloni, Alessandro; Chechkin, Aleksei; Klafter, Joseph

    2010-04-23

    Starting from a generalized elastic model which accounts for the stochastic motion of several physical systems such as membranes, (semi)flexible polymers, and fluctuating interfaces among others, we derive the fractional Langevin equation (FLE) for a probe particle in such systems, in the case of thermal initial conditions. We show that this FLE is the only one fulfilling the fluctuation-dissipation relation within a new family of fractional Brownian motion equations. The FLE for the time-dependent fluctuations of the donor-acceptor distance in a protein is shown to be recovered. When the system starts from nonthermal conditions, the corresponding FLE, which does not fulfill the fluctuation-dissipation relation, is derived.

  18. Rigidity of transmembrane proteins determines their cluster shape

    CERN Document Server

    Jafarinia, Hamidreza; Jalali, Mir Abbas

    2015-01-01

    Protein aggregation in cell membrane is vital for majority of biological functions. Recent experimental results suggest that transmembrane domains of proteins such as $\\alpha$-helices and $\\beta$-sheets have different structural rigidity. We use molecular dynamics simulation of a coarse-grained model of protein-embedded lipid membranes to investigate the mechanisms of protein clustering. For a variety of protein concentrations, our simulations in thermal equilibrium conditions reveal that the structural rigidity of transmembrane domains dramatically affects interactions and changes the shape of the cluster. We have observed stable large aggregates even in the absence of hydrophobic mismatch which has been previously proposed as the mechanism of protein aggregation. According to our results, semi-flexible proteins aggregate to form two-dimensional clusters while rigid proteins, by contrast, form one-dimensional string-like structures. By assuming two probable scenarios for the formation of a two-dimensional tr...

  19. Direct visualization of flow-induced conformational transitions of single actin filaments in entangled solutions

    CERN Document Server

    Kirchenbuechler, Inka; Kurniawan, Nicholas A; Koenderink, Gijsje H; Lettinga, M Paul

    2015-01-01

    While semi-flexible polymers and fibers are an important class of material due to their rich mechanical properties, it remains unclear how these properties relate to the microscopic conformation of the polymers. Actin filaments constitute an ideal model polymer system due to their micron-sized length and relatively high stiffness that allow imaging at the single filament level. Here we study the effect of entanglements on the conformational dynamics of actin filaments in shear flow. We directly measure the full three-dimensional conformation of single actin filaments, using confocal microscopy in combination with a counter-rotating cone-plate shear cell. We show that initially entangled filaments form disentangled orientationally ordered hairpins, confined in the flow-vorticity plane. In addition, shear flow causes stretching and shear alignment of the hairpin tails, while the filament length distribution remains unchanged. These observations explain the strain-softening and shear-thinning behavior of entangl...

  20. Peptide Suboptimal Conformation Sampling for the Prediction of Protein-Peptide Interactions.

    Science.gov (United States)

    Lamiable, Alexis; Thévenet, Pierre; Eustache, Stephanie; Saladin, Adrien; Moroy, Gautier; Tuffery, Pierre

    2017-01-01

    The blind identification of candidate patches of interaction on the protein surface is a difficult task that can hardly be accomplished without a heuristic or the use of simplified representations to speed up the search. The PEP-SiteFinder protocol performs a systematic blind search on the protein surface using a rigid docking procedure applied to a limited set of peptide suboptimal conformations expected to approximate satisfactorily the conformation of the peptide in interaction. All steps rely on a coarse-grained representation of the protein and the peptide. While simple, such a protocol can help to infer useful information, assuming a critical analysis of the results. Moreover, such a protocol can be extended to a semi-flexible protocol where the suboptimal conformations are directly folded in the vicinity of the receptor.

  1. Mechanical Behavior and Failure Mechanism of Recycled Semi-lfexible Pavement Material

    Institute of Scientific and Technical Information of China (English)

    DING Qingjun; ZHAO Mingyu; SHEN Fan; ZHANG Xiaoqiang

    2015-01-01

    The mechanical behavior and failure mechanism of recycled semi-lfexible pavement material were investigated by different scales method. The macroscopic mechanical behavior of samples was studied by static and dynamic splitting tensile tests on mechanics testing system (MTS). The mechanical analysis in micro scale was carried out by material image analysis method and ifnite element analysis system. The strains of recycled semi-lfexible pavement material on samples surface and in each phase materials were obtained. The test results reveal that the performance of recovered asphalt binder was the major determinant on the structural stability of recycled semi-lfexible pavement material. The asphalt binder with high viscoelasticity could delay the initial cracking time and reduce the residual strain under cyclic loading conditions. The failure possibility order of each phase in recycled semi-flexible pavement material was asphalt binder, reclaimed aggregate, cement paste and virgin aggregate.

  2. Nonlinear mechanics of hybrid polymer networks that mimic the complex mechanical environment of cells

    Science.gov (United States)

    Jaspers, Maarten; Vaessen, Sarah L.; van Schayik, Pim; Voerman, Dion; Rowan, Alan E.; Kouwer, Paul H. J.

    2017-05-01

    The mechanical properties of cells and the extracellular environment they reside in are governed by a complex interplay of biopolymers. These biopolymers, which possess a wide range of stiffnesses, self-assemble into fibrous composite networks such as the cytoskeleton and extracellular matrix. They interact with each other both physically and chemically to create a highly responsive and adaptive mechanical environment that stiffens when stressed or strained. Here we show that hybrid networks of a synthetic mimic of biological networks and either stiff, flexible and semi-flexible components, even very low concentrations of these added components, strongly affect the network stiffness and/or its strain-responsive character. The stiffness (persistence length) of the second network, its concentration and the interaction between the components are all parameters that can be used to tune the mechanics of the hybrids. The equivalence of these hybrids with biological composites is striking.

  3. Virtual screening studies reveal linarin as a potential natural inhibitor targeting CDK4 in retinoblastoma.

    Science.gov (United States)

    Sivashanmugam, Muthukumaran; Raghunath, Chandana; Vetrivel, Umashankar

    2013-10-01

    To find out whether linarin can be used as a potential natural inhibitor to target CDK4 in retinoblastoma using virtual screening studies. In this study, molecular modeling and protein structure optimization was performed for crystal structure of CDK4 (PDB id: 3G33), and was subjected to Molecular Dynamics (MD) simulation for 10 nanoseconds, as a preparatory process for docking. Furthermore, the stable conformation obtained in the MD simulation was utilized for virtual screening against the library of natural compounds in Indian Plant Anticancer Compounds Database (InPACdb) using AutoDock Vina. Finally, best docked ligands were revalidated individually through semi-flexible docking by AutoDock 4.0. The CDK4 structure was stereochemically optimized to fix clashes and bad angles, which placed 96.4% residues in the core region of Ramachandran plot. The final structure of CDK4 that emerged after MD simulation was proven to be highly stable as per different validation tools. Virtual screening and docking was carried out for CDK4 against optimized ligands from InPACdb through AutoDock Vina. This inferred Linarin (Inpacdb AC.NO. acd0073) as a potential therapeutic agent with binding energy of -8.9 kJ/mol. Furthermore, it was also found to be valid as per AutoDock 4.0 semi-flexible docking procedure, with the binding energy of -8.18 kJ/mol and Ki value of 1.01 μM. The docking results indicate linarin, a flavonoid plant compound, as a potential inhibitor of CDK4 compared to some of the currently practiced anticancer drugs for retinoblastoma. This finding can be extended to experimental validation to assess the in vivo efficacy of the identified compound.

  4. Detection of metallic and plastic landmines using the GPR and 2-D resistivity techniques

    Directory of Open Access Journals (Sweden)

    M. Metwaly

    2007-12-01

    Full Text Available Low and non-metallic landmines are one of the most difficult subsurface targets to be detected using several geophysical techniques. Ground penetrating radar (GPR performance at different field sites shows great success in detecting metallic landmines. However significant limitations are taking place in the case of low and non-metallic landmines. Electrical resistivity imaging (ERI technique is tested to be an alternative or confirmation technique for detecting the metallic and non-metallic landmines in suspicious cleared areas. The electrical resistivity responses using forward modeling for metallic and non-metallic landmines buried in dry and wet environments utilizing the common electrode configurations have been achieved. Roughly all the utilized electrode arrays can establish the buried metallic and plastic mines correctly in dry and wet soil. The accuracy differs from one array to the other based on the relative resistivity contrast to the host soil and the subsurface distribution of current and potential lines as well as the amplitude of the noises in the data. The ERI technique proved to be fast and effective tool for detecting the non-metallic mines especially in the conductive environment whereas the performances of the other metal detector (MD and GPR techniques show great limitation.

  5. Petrography, diagenesis and geotechnical properties of the El-Rufuf Formation (Thebes Group), El-Kharga Oasis, Egypt

    Science.gov (United States)

    Bashed, M. A.; Sediek, K. N.

    1997-10-01

    The El-Rufuf Formation (Thebes Group) outcrops widely in Egypt. It is quarried as an ornamental building stone and used as slabs in walls and floors. It is also important in foundation construction. The geotechnical behaviour of these rocks is commonly related to stratigraphical position, controlled by their petrography and textural and diagenetic features. The El-Rufuf Formation of Naqb Assiut, El-Kharga Oasis, consists of 63 m of micritic and neomorphosed limestones which are marly at the base. Microfacies analysis of these limestones indicates an inner to middle shelf open marine environment. The most common diagenetic features are neomorphism, silicification, dissolution and stylolites. There are clear relationships between the measured compressive strength of rocks and the facies and diagenetic features. Neomorphic sparry limestone has the lowest compressive strength, while cherty biomicritic limestone shows the highest values. Micritic and biomicritic limestones show intermediate values. Some anisotropism of compressive strength values is recorded in the stylolitic limestones and in the foliated marly part of the formation. The present study reveals that the El-Rufuf limestones, according to Deere's (1968) classification, are low to medium strength rocks with low modulus ratios (DL-CL), while the marly parts of the formation are low strength rocks with low modulus ratios (EL). The rocks of the marly part of the El-Rufuf Formation are unstable with regard to water and therefore have a zero softness coefficient.

  6. Self-assembled three dimensional network designs for soft electronics

    Science.gov (United States)

    Jang, Kyung-In; Li, Kan; Chung, Ha Uk; Xu, Sheng; Jung, Han Na; Yang, Yiyuan; Kwak, Jean Won; Jung, Han Hee; Song, Juwon; Yang, Ce; Wang, Ao; Liu, Zhuangjian; Lee, Jong Yoon; Kim, Bong Hoon; Kim, Jae-Hwan; Lee, Jungyup; Yu, Yongjoon; Kim, Bum Jun; Jang, Hokyung; Yu, Ki Jun; Kim, Jeonghyun; Lee, Jung Woo; Jeong, Jae-Woong; Song, Young Min; Huang, Yonggang; Zhang, Yihui; Rogers, John A.

    2017-06-01

    Low modulus, compliant systems of sensors, circuits and radios designed to intimately interface with the soft tissues of the human body are of growing interest, due to their emerging applications in continuous, clinical-quality health monitors and advanced, bioelectronic therapeutics. Although recent research establishes various materials and mechanics concepts for such technologies, all existing approaches involve simple, two-dimensional (2D) layouts in the constituent micro-components and interconnects. Here we introduce concepts in three-dimensional (3D) architectures that bypass important engineering constraints and performance limitations set by traditional, 2D designs. Specifically, open-mesh, 3D interconnect networks of helical microcoils formed by deterministic compressive buckling establish the basis for systems that can offer exceptional low modulus, elastic mechanics, in compact geometries, with active components and sophisticated levels of functionality. Coupled mechanical and electrical design approaches enable layout optimization, assembly processes and encapsulation schemes to yield 3D configurations that satisfy requirements in demanding, complex systems, such as wireless, skin-compatible electronic sensors.

  7. New Developments of Ti-Based Alloys for Biomedical Applications

    Directory of Open Access Journals (Sweden)

    Yuhua Li

    2014-03-01

    Full Text Available Ti-based alloys are finding ever-increasing applications in biomaterials due to their excellent mechanical, physical and biological performance. Nowdays, low modulus β-type Ti-based alloys are still being developed. Meanwhile, porous Ti-based alloys are being developed as an alternative orthopedic implant material, as they can provide good biological fixation through bone tissue ingrowth into the porous network. This paper focuses on recent developments of biomedical Ti-based alloys. It can be divided into four main sections. The first section focuses on the fundamental requirements titanium biomaterial should fulfill and its market and application prospects. This section is followed by discussing basic phases, alloying elements and mechanical properties of low modulus β-type Ti-based alloys. Thermal treatment, grain size, texture and properties in Ti-based alloys and their limitations are dicussed in the third section. Finally, the fourth section reviews the influence of microstructural configurations on mechanical properties of porous Ti-based alloys and all known methods for fabricating porous Ti-based alloys. This section also reviews prospects and challenges of porous Ti-based alloys, emphasizing their current status, future opportunities and obstacles for expanded applications. Overall, efforts have been made to reveal the latest scenario of bulk and porous Ti-based materials for biomedical applications.

  8. Laser-deposited Ti-Nb-Zr-Ta orthopedic alloys.

    Science.gov (United States)

    Banerjee, R; Nag, S; Samuel, S; Fraser, H L

    2006-08-01

    The complex quaternary Ti-35Nb-7Zr-5Ta orthopedic alloy has been successfully deposited from a powder feedstock consisting of a blend of elemental titanium, niobium, zirconium, and tantalum powders, using the laser engineered net-shaping (LENStrade mark) process. In the as laser-deposited form, these alloys exhibit a substantially higher tensile strength as compared with more conventionally processed counterparts of similar composition, while maintaining excellent ductility and a low modulus. Furthermore, the as-deposited alloys appear to exhibit a texture, with a substantially large number of grains of the beta phase aligning one of their axes nearly normal to the substrate or parallel to the growth direction. The microstructure of the as-deposited as well as tensile-tested alloys have been characterized in detail using scanning electron microscopy (SEM), orientation microscopy (OM), and transmission electron microscopy (TEM). Formation of a high density of shear bands, possibly arising from slip localization due to precipitates of the omega phase in the beta matrix, is clearly evident in the tensile-tested sample. The enhanced tensile strength and low modulus in these laser-deposited alloys coupled with the ability to form near-net shape components makes LENS an attractive processing technology for orthopedic implants.

  9. The Sinuous Target

    Energy Technology Data Exchange (ETDEWEB)

    Zwaska, R. [Fermilab

    2015-06-01

    We report on the concept for a target material comprised of a multitude of interlaced wires of small dimension. This target material concept is primarily directed at high-power neutrino targets where the thermal shock is large due to small beam sizes and short durations; it also has applications to other high-power targets, particularly where the energy deposition is great or a high surface area is preferred. This approach ameliorates the problem of thermal shock by engineering a material with high strength on the micro-scale, but a very low modulus of elasticity on the meso-scale. The low modulus of elasticity is achieved by constructing the material of spring-like wire segments much smaller than the beam dimension. The intrinsic bends of the wires will allow them to absorb the strain of thermal shock with minimal stress. Furthermore, the interlaced nature of the wires provides containment of any segment that might become loose. We will discuss the progress on studies of analogue materials and fabrication techniques for sinuous target materials.

  10. Subsidence characterization and modeling for engineered facilities in Arizona, USA

    Science.gov (United States)

    Rucker, M. L.; Fergason, K. C.; Panda, B. B.

    2015-11-01

    Several engineered facilities located on deep alluvial basins in southern Arizona, including flood retention structures (FRS) and a coal ash disposal facility, have been impacted by up to as much as 1.8 m of differential land subsidence and associated earth fissuring. Compressible basin alluvium depths are as deep as about 300 m, and historic groundwater level declines due to pumping range from 60 to more than 100 m at these facilities. Addressing earth fissure-inducing ground strain has required alluvium modulus characterization to support finite element modeling. The authors have developed Percolation Theory-based methodologies to use effective stress and generalized geo-material types to estimate alluvium modulus as a function of alluvium lithology, depth and groundwater level. Alluvial material modulus behavior may be characterized as high modulus gravel-dominated, low modulus sand-dominated, or very low modulus fines-dominated (silts and clays) alluvium. Applied at specific aquifer stress points, such as significant pumping wells, this parameter characterization and quantification facilitates subsidence magnitude modeling at its' sources. Modeled subsidence is then propagated over time across the basin from the source(s) using a time delay exponential decay function similar to the soil mechanics consolidation coefficient, only applied laterally. This approach has expanded subsidence modeling capabilities on scales of engineered facilities of less than 2 to more than 15 km.

  11. Self-assembled three dimensional network designs for soft electronics

    Science.gov (United States)

    Jang, Kyung-In; Li, Kan; Chung, Ha Uk; Xu, Sheng; Jung, Han Na; Yang, Yiyuan; Kwak, Jean Won; Jung, Han Hee; Song, Juwon; Yang, Ce; Wang, Ao; Liu, Zhuangjian; Lee, Jong Yoon; Kim, Bong Hoon; Kim, Jae-Hwan; Lee, Jungyup; Yu, Yongjoon; Kim, Bum Jun; Jang, Hokyung; Yu, Ki Jun; Kim, Jeonghyun; Lee, Jung Woo; Jeong, Jae-Woong; Song, Young Min; Huang, Yonggang; Zhang, Yihui; Rogers, John A.

    2017-01-01

    Low modulus, compliant systems of sensors, circuits and radios designed to intimately interface with the soft tissues of the human body are of growing interest, due to their emerging applications in continuous, clinical-quality health monitors and advanced, bioelectronic therapeutics. Although recent research establishes various materials and mechanics concepts for such technologies, all existing approaches involve simple, two-dimensional (2D) layouts in the constituent micro-components and interconnects. Here we introduce concepts in three-dimensional (3D) architectures that bypass important engineering constraints and performance limitations set by traditional, 2D designs. Specifically, open-mesh, 3D interconnect networks of helical microcoils formed by deterministic compressive buckling establish the basis for systems that can offer exceptional low modulus, elastic mechanics, in compact geometries, with active components and sophisticated levels of functionality. Coupled mechanical and electrical design approaches enable layout optimization, assembly processes and encapsulation schemes to yield 3D configurations that satisfy requirements in demanding, complex systems, such as wireless, skin-compatible electronic sensors. PMID:28635956

  12. Design and Construction of Large Amyloid Fibers

    Directory of Open Access Journals (Sweden)

    Devin M. Ridgley

    2015-04-01

    Full Text Available Mixtures of “template” and “adder” proteins self-assemble into large amyloid fibers of varying morphology and modulus. Fibers range from low modulus, rectangular cross-sectioned tapes to high modulus, circular cross-sectioned cylinders. Varying the proteins in the mixture can elicit “in-between” morphologies, such as elliptical cross-sectioned fibers and twisted tapes, both of which have moduli in-between rectangular tapes and cylindrical fibers. Experiments on mixtures of proteins of known amino acid sequence show that control of the large amyloid fiber morphology is dependent on the amount of glutamine repeats or “Q-blocks” relative to hydrophobic side chained amino acids such as alanine, isoleucine, leucine, and valine in the adder protein. Adder proteins with only hydrophobic groups form low modulus rectangular cross-sections and increasing the Q-block content allows excess hydrogen bonding on amide groups that results in twist and higher modulus. The experimental results show that large amyloid fibers of specific shape and modulus can be designed and controlled at the molecular level.

  13. Mechanical properties of a Gum-type Ti-Nb-Zr-Fe-O alloy

    Science.gov (United States)

    Nocivin, Anna; Cinca, Ion; Raducanu, Doina; Cojocaru, Vasile Danut; Popovici, Ion Alexandru

    2017-08-01

    A new Gum-type alloy (Ti-Nb-Zr-Fe-O) in which Fe is used instead of Ta was subjected to a particular thermomechanical processing scheme to assess whether its mechanical characteristics (fine β-grains with high strength and low modulus) render it suitable as a biomedical implant material. After a homogenization treatment followed by cold-rolling with 50% reduction, the specimens were subjected to one of three different recrystallization treatments at 1073, 1173, and 1273 K. The structural and mechanical properties of all of the treated specimens were analyzed. The mechanical characterization included tensile tests, microhardness determinations, and fractography by scanning electron microscopy. The possible deformation mechanisms were discussed using the \\overline {Bo} - \\overline {Md} diagram. By correlating all of the experimental results, we concluded that the most promising processing variant corresponds to recrystallization at 1073 K, which can provide suitable mechanical characteristics for this type of alloys: high yield and ultimate tensile strengths (1038 and 1083 MPa, respectively), a low modulus of elasticity (62 GPa), and fine crystalline grain size (approximately 50 μm).

  14. New Developments of Ti-Based Alloys for Biomedical Applications

    Science.gov (United States)

    Li, Yuhua; Yang, Chao; Zhao, Haidong; Qu, Shengguan; Li, Xiaoqiang; Li, Yuanyuan

    2014-01-01

    Ti-based alloys are finding ever-increasing applications in biomaterials due to their excellent mechanical, physical and biological performance. Nowdays, low modulus β-type Ti-based alloys are still being developed. Meanwhile, porous Ti-based alloys are being developed as an alternative orthopedic implant material, as they can provide good biological fixation through bone tissue ingrowth into the porous network. This paper focuses on recent developments of biomedical Ti-based alloys. It can be divided into four main sections. The first section focuses on the fundamental requirements titanium biomaterial should fulfill and its market and application prospects. This section is followed by discussing basic phases, alloying elements and mechanical properties of low modulus β-type Ti-based alloys. Thermal treatment, grain size, texture and properties in Ti-based alloys and their limitations are dicussed in the third section. Finally, the fourth section reviews the influence of microstructural configurations on mechanical properties of porous Ti-based alloys and all known methods for fabricating porous Ti-based alloys. This section also reviews prospects and challenges of porous Ti-based alloys, emphasizing their current status, future opportunities and obstacles for expanded applications. Overall, efforts have been made to reveal the latest scenario of bulk and porous Ti-based materials for biomedical applications. PMID:28788539

  15. Research on Selective Shredding of Wasted Printed Circuit Boards

    Institute of Scientific and Technical Information of China (English)

    曹亦俊; 文学峰; 赵跃民

    2002-01-01

    Electronic scrap, especially wasted printed circuit boards (PCBs), is regarded as an environmental challenge. At present, the physical separation is thought to be the environmental friendly and economical method of treating and reutilizing electronic waste. An effective liberation of metals from non-metallic components is a crucial step towards mechanical separation and recycling of wasted PCBs. In this paper, the selective shredding theory and mechanics characteristics of wasted PCBs were analyzed, and the shredded experiments of wasted PCBs by hammer mill were investigated. The result shows that the selective shredding exists in the wasted PCBs shredded process by hammer mill. The shredding velocity of non-metallic components is far greater than that of metals in the wasted PCBs shredding, which makes the metals concentrate in the coarser fraction. And the impact force of hammer mill is superior to metal liberation from non-metallic components, a satisfied metal liberation degree can be achieved in the wasted PCBs shredding by hammer mill.

  16. Fast steel-cleanness characterization by means of laser-assisted plasma spectrometric methods.

    Science.gov (United States)

    Müller, Gregor; Stahnke, Frank; Bleiner, Davide

    2006-12-15

    Laser-assisted plasma spectrometry is a palette of analytical techniques (L-OES, LA-ICP-MS) capable of fast spatially-resolved elemental analysis in the micrometer range. For fast estimation of the occurrence in steel samples of non-metallic inclusions, which degrade the material's technical properties, simultaneous OES detection and sequential ICP-MS detection were compared. Histograms were obtained for the intensity distribution of the acquired signals (laser pulse statistics). The skewness coefficient of the histograms for Al (indicator of non-metallic inclusions) was found to be clearly dependent on the fraction of non-metallic inclusions in the case of scanning L-OES. For LA-ICP-MS less clear dependence was observed, which was influenced by the acquisition characteristics. In fact, less measurement throughput limited for LA-ICP-MS the counting statistics to an extent that overrides the benefit of higher detection power as compared to L-OES.

  17. Effects of CeF3 on properties of self-shielded flux cored wire

    Institute of Scientific and Technical Information of China (English)

    Yu Ping; Tian Zhiling; Pan Chuan; Xue Jin

    2006-01-01

    Effects of CeF3 on properties of self-shielded flux cored wire including welding process, inclusions in weld metal and mechanical properties are systematically studied. Welding smoke and spatter are reduced with the addition of CeF3. The main non-metallic inclusions in weld metal are AlN and Al2 O3. CeF3 can refine non-metallic inclusions and reduce the amount of large size inclusions, which is attributed to the inclusion floating behavior during the solidification of weld metal. The low temperature impact toughness is improved by adding suitable amount of CeF3 in the flux.

  18. COMPUTATIONAL FLUID DYNAMICS APPLIED TO THE STUDY OF INCLUSIONS FLOTATION IN STEELS FOR AUTOMOTIVE INDUSTRY

    Directory of Open Access Journals (Sweden)

    Ângelo Máximo Fernandes Marins

    2013-03-01

    Full Text Available The practice of inert gas bubbling in steel refining ladle aims the removal of non-metallic inclusions, in addition to thermal and compositional homogenization. Through physical and mathematical models of a secondary ladle refining, the effects of bubbling flow of inert gas and the number of porous plugs located at the bottom of the ladle are investigated. The velocity fields and flotation of non-metallic inclusions are analyzed by physical and mathematical modeling. The results are validated by analysis of images (PIV and the macroscopic model is compared by industrial results for inclusions analysis for steels used in the automotive sector

  19. Wide – ranging influence of mischmetal on properties of G17CrMo5-5 cast steel

    Directory of Open Access Journals (Sweden)

    J. Kasińska

    2015-01-01

    Full Text Available This paper presents influence of rare earth metals (REM on the mechanical properties, microstructure and morphology of non metallic inclusions as well as the cracking mechanism of G17CrMo5-5 high temperature cast steel. The research has been performed on successive industrial melts. It was found that non metallic inclusions the cracking mechanism of Charpy specimens and the impact strength were all changed. The following properties were tested: mechanical properties (Rm, Re, plastic properties (A, Z, impact strength (SCI and the KJC stress intensity factor.

  20. ULTRASONIC SEPARATION OF MICRO-SIZED INCLUSIONSIN MOLTEN METAL

    Institute of Scientific and Technical Information of China (English)

    X.Q. Bai; J.C. He

    2001-01-01

    The coagulation time and position of micro-sized non-metallic inclusions in molten metal during ultrasonic separation process were investigated, and the motion course of micro-sized non-metallic inclusions in an ultrasonic standing wave field was numerically simulated. The results of theoretical analysis and numerical simulation show that the movement of inclusions depends on the balance between the acoustic radiation force, effective buoyancy force and viscous drag force. It is presented that micro-sized inclusions, agglomerated at antinode-planes may be removed further with horizon tal ultrasound.``

  1. Studying microstructure of heat resistant steel deoxidized by barium ferrosilicon

    Directory of Open Access Journals (Sweden)

    A. Z. Issagulov

    2016-07-01

    Full Text Available The paper examined the nature and distribution of non-metallic inclusions in the heat-resistant steel 12H1MF (0,12 % С, 1 % Сr, 0,5 - 0,6 Mo, 0,5 % V, ferrosilicobarim. As a reference, used by steel, deoxidized silicon. Melting was carried out in a laboratory, research-metallic inclusions, their shape and distribution, pollution index were studied according to conventional methods. Studies have shown that ferrosilicobarim deoxidation in an amount of 0,1 - 0,2 %, reduce the overall pollution index of non-metallic inclusions and change the nature of their distribution.

  2. [The clinical application of zirconium-dioxide-ceramics. Case report].

    Science.gov (United States)

    Somfai, Dóra; Zsigmond, Ágnes; Károlyházy, Katalin; Kispély, Barbara; Hermann, Péter

    2015-12-01

    Due to its outstanding physical, mechanical and esthetic properties, zirconium-dioxide is one of the most popular non-metal denture, capable of surpassing PFM in most cases. The recent advances of CAD/CAM technology makes it a good alternitve. Here we show the usefulness of zirconium-dioxide in everyday dental practice through three case reports.

  3. Time reversal communication system

    Science.gov (United States)

    Candy, James V.; Meyer, Alan W.

    2008-12-02

    A system of transmitting a signal through a channel medium comprises digitizing the signal, time-reversing the digitized signal, and transmitting the signal through the channel medium. The channel medium may be air, earth, water, tissue, metal, and/or non-metal.

  4. Worldwide distribution of soil dielectric and thermal properties

    NARCIS (Netherlands)

    Hendrickx, J.M.H.; Dam, R.L. van; Borchers, B.; Curtis, J.; Lensen, H.A.; Harmon, R.

    2003-01-01

    Ground penetrating radar and thermal sensors hold much promise for the detection of non-metallic land mines. In previous work we have shown that the performance of ground penetrating radar strongly depends on field soil conditions such as texture, water content, and soil-water salinity since these s

  5. Frustrated Lewis pairs-assisted reduction of carbonyl compounds

    DEFF Research Database (Denmark)

    Marek, Ales; Pedersen, Martin Holst Friborg

    2015-01-01

    An alternative and robust method for the reduction of carbonyl groups by frustrated Lewis pairs (FLPs) is reported in this paper. With its very mild reaction conditions, good to excellent yields, absolute regioselectivity and the non-metallic character of the reagent, it provides an excellent too...

  6. Sound wave and laser excitation for acousto-optical landmine detection

    NARCIS (Netherlands)

    Lutzmann, P.; Heuvel, J.C. van den; Klien, V.; Schleijpen, H.M.A.; Hebel, M.; Putten, F.J.M. van

    2003-01-01

    Acoustic landmine detection (ALD) is a technique for the detection of buried landmines including non-metal mines. An important issue in ALD is the acoustic excitation of the soil. Laser excitation is promising for complete standoff detection using lasers for excitation and monitoring. Acoustic excit

  7. Henan Plans to Shut Down Over 475 mines by 2015

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    <正>Recently, the General Office of Henan Provin-cial Government printed and distributed "He-nan Province Metal and Non-metal Mine Recti-fication Shutdown Work Plan (2012-2015)" (The Plan). By carrying out rectification and

  8. Microstructural Features Controlling the Variability in Low-Cycle Fatigue Properties of Alloy Inconel 718DA at Intermediate Temperature

    Science.gov (United States)

    Texier, Damien; Gómez, Ana Casanova; Pierret, Stéphane; Franchet, Jean-Michel; Pollock, Tresa M.; Villechaise, Patrick; Cormier, Jonathan

    2016-03-01

    The low-cycle fatigue behavior of two direct-aged versions of the nickel-based superalloy Inconel 718 (IN718DA) was examined in the low-strain amplitude regime at intermediate temperature. High variability in fatigue life was observed, and abnormally short lifetimes were systematically observed to be due to crack initiation at (sub)-surface non-metallic inclusions. However, crack initiation within (sub)-surface non-metallic inclusions did not necessarily lead to short fatigue life. The macro- to micro-mechanical mechanisms of deformation and damage have been examined by means of detailed microstructural characterization, tensile and fatigue mechanical tests, and in situ tensile testing. The initial stages of crack micro-propagation from cracked non-metallic particles into the surrounding metallic matrix occupies a large fraction of the fatigue life and requires extensive local plastic straining in the matrix adjacent to the cracked inclusions. Differences in microstructure that influence local plastic straining, i.e., the δ-phase content and the grain size, coupled with the presence of non-metallic inclusions at the high end of the size distribution contribute strongly to the fatigue life variability.

  9. LDEF- 69 Months in Space. Second Post-Retrieval Symposium, Part 2

    Science.gov (United States)

    1992-06-01

    projectile (Gault and Wedekind , 1978). Impacts in solid non- metallic targets (Mandeville and Vedder, 1971) show central craters and spallation regions but...Chicago. Gault, D.E. and Wedekind , J.A.: (1978). "Experimental Studies of Oblique Impact." Proc. 9th Lunar Planet Sci. Conf., 3843-3875. 422 GrUn, E., Zook

  10. Laser-induced acoustic landmine detection with experimental results on buried landmines

    NARCIS (Netherlands)

    Heuvel, J.C. van den; Putten, F.J.M. van; Koersel, A.C. van; Schleijpen, H.M.A.

    2004-01-01

    Acoustic landmine detection (ALD) is a technique for the detection of buried landmines including non-metal mines. Since it gives complementary results with GPR or metal detection, sensor fusion of these techniques with acoustic detection would give promising results. Two methods are used for the aco

  11. A new integrated approach for characterizing the soil electromagnetic properties and detecting landmines using a hand-held vector network analyzer

    NARCIS (Netherlands)

    Lopra, O.; Lambot, S.; Slob, E.; Vanclooster, M.; Macq, B.; Milisavljevic, N.

    2006-01-01

    The application of ground-penetrating radar (GPR) in humanitarian demining labors presents two major challenges: (1) the development of affordable and practical systems to detect metallic and non-metallic antipersonnel (AP) landmines under different conditions, and (2) the development of accurate so

  12. 40 CFR 761.357 - Reporting the results of the procedure used to simulate leachate generation.

    Science.gov (United States)

    2010-07-01

    ... simulate leachate generation as micrograms PCBs per liter of extract from a 100 gram sample of dry bulk... used to simulate leachate generation. 761.357 Section 761.357 Protection of Environment ENVIRONMENTAL..., PROCESSING, DISTRIBUTION IN COMMERCE, AND USE PROHIBITIONS Sampling Non-Liquid, Non-Metal PCB Bulk...

  13. Exposure to diesel exhaust linked to lung cancer in miners

    Science.gov (United States)

    In a study of non-metal miners in the United States, federal government scientists reported that heavy exposure to diesel exhaust increased risk of death from lung cancer. The research, all part of the Diesel Exhaust in Miners Study, was designed to evalu

  14. 77 FR 40836 - Pennsylvania Regulatory Program

    Science.gov (United States)

    2012-07-11

    ... hearing until 4 p.m., EST on July 26, 2012. ADDRESSES: You may submit comments, identified by SATS No. PA... of the coal ash prior to placement and properly identify the sources of the coal ash. When coal ash... non-metals and anions (other than sulfate and fluoride) the waste classification standard for...

  15. Environmental Tax Reforms and Mitigation for Energy-intensive Industries: Some Lessons from European Experience

    DEFF Research Database (Denmark)

    Andersen, Mikael Skou

    2009-01-01

    The purpose of this paper is to analyse in more detail the international experiences in applying carbon-energy taxation in two important energy-intensive sectors; iron and steel, as well as non-metallic mineral products (where cement is the most significant subsector)....

  16. The Mean vs Life-Limiting Fatigue Response of a Ni-Base Superalloy, Part 1: Mechanisms (Preprint)

    Science.gov (United States)

    2008-09-01

    34 lifetime distribution [3, 4]. A more significant impact on the uncertainty in life-prediction may, however, be realized by a paradigm shift in the...failures, and (b) non-metallic particle vs. pore related failures. Since the free surface and the region close to it experience a higher microplasticity

  17. environmental impact of aggregate mining by crush rock industries ...

    African Journals Online (AJOL)

    2012-07-02

    Jul 2, 2012 ... method concerned with the extraction of non-fuel and non-metal minerals from .... pacity, problems in human relations, and a number of ... sons [19], sleep disturbance on the other hand is con- ..... season. This is expected as the dominant wind system .... Chrysanthus, C. Evaluating Baseline Data for Trace.

  18. Development and Implementation of the National Test Facility (NaTeF) for Fuels and Propulsion

    Science.gov (United States)

    2013-10-01

    Vinyl chloride Methane toluene Nitrous oxide Methyl ethyl ketone The TSI Scanning Mobility Particle Sizer (SMPS) consists of the...Fischer-Tropsch Derived (Iso Parafinnic Kerosene ) and Blended FT-Petroleum- Derived Fuels with Non-metallic Materials. 10th International Conference on

  19. Purifying effect of new flux on magnesium alloy

    Institute of Scientific and Technical Information of China (English)

    高洪涛; 吴国华; 丁文江; 朱燕萍

    2004-01-01

    A new flux which can remove both Fe and non-metallic inclusions in magnesium alloy was introduced.The Fe content of the magnesium alloy can be decreased greatly from 0. 062% to lower than 0. 005% (degree of AZ91D) after being purified by this new flux. The optimum addition of B2O3 in the flux is 0. 58 % by Gaussian Curve Fitting. Corrosion rate was measured after the specimen being immersed in 5 % NaCl solution for 3 d. The resuits show that the corrosion rate of the magnesium alloy after purification by the new flux is only 0.3 mg · cm-2 ·d-1. On the other hand, non-metallic inclusions in the magnesium alloy decrease with increasing addition of JDMJ in the new flux. Average volume fraction of the non-metallic inclusions in the magnesium alloy decreases from 1.52 % to 1.08%, which leads to improvement in the mechanical properties of the magnesium alloy by 30%. The mechanisms of Fe reduction and non-metallic inclusion-removing in magnesium melt by purification with the new flux were also revealed.

  20. 40 CFR 761.359 - Reporting the PCB concentrations in samples.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Reporting the PCB concentrations in... COMMERCE, AND USE PROHIBITIONS Sampling Non-Liquid, Non-Metal PCB Bulk Product Waste for Purposes of Characterization for PCB Disposal in Accordance With § 761.62, and Sampling PCB Remediation Waste Destined for...

  1. In situ performance and potential applications of a thermal bed-load measurement method

    CSIR Research Space (South Africa)

    Ilgner, HJ

    2010-09-01

    Full Text Available Methods to detect the flow condition at the pipeline invert are reviewed. New results of a small heated plate inserted into a non-metallic pipe are presented. This thermal method is based on mini-heaters and can detect erratic flow behaviour near...

  2. The Ministry of Land and Resources Supports the Western Region to Intensify Efforts in Prospecting and Developing Advantageous Mineral Resources

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    <正>The Ministry of Land and Resources supports the western region to intensify efforts in prospecting, developing and utilizing advantageous mineral resources including petrol, natural gas, and coal resources, build advantageous mineral economy, speed up the development of nonferrous metals, key building materials, and non metal mineral resources with obvious

  3. Polarization-stable dual-color DFB fibre laser system for CW terahertz generation

    DEFF Research Database (Denmark)

    Eichhorn, Finn; Petersen, Jens Engholm; Jepsen, Peter Uhd

    ” the walls of non-metallic containers as well as clothing to identify hidden objects. For this reason, large efforts are currently being put into the exploitation of the “THz gap” to investigate new applications in the safety and security sector as well as industrial environments. We have developed...

  4. Demonstration Report for Visual Sample Plan (VSP) Verification Sampling Methods at the Navy/DRI Site

    Science.gov (United States)

    2011-08-01

    time kinematic ( RTK ) global positioning system ( GPS ) performed anomaly reacquisition. The procedure for reacquiring the location of the anomalies was...load the target anomalies onto the RTK GPS positioning system in the correct format, and 3. place a non-metallic pin flag marked with the unique...Demonstrate the utility of the PRV sampling modules and gain regulator acceptance

  5. China Report, Science and Technology.

    Science.gov (United States)

    2007-11-02

    organizations to improve people’s living and working conditions and dissuade them from smoking, drinking excessively and eating too many pickled and...the use of titanium alloys, molybdenum alloys, as well as graphite composite materials, fiber glass and other non-metallic materials; in the area of

  6. Worldwide distribution of soil dielectric and thermal properties

    NARCIS (Netherlands)

    Hendrickx, J.M.H.; Dam, R.L. van; Borchers, B.; Curtis, J.; Lensen, H.A.; Harmon, R.

    2003-01-01

    Ground penetrating radar and thermal sensors hold much promise for the detection of non-metallic land mines. In previous work we have shown that the performance of ground penetrating radar strongly depends on field soil conditions such as texture, water content, and soil-water salinity since these

  7. Impact of soil water content on landmine detection using radar and thermal infared sensors

    NARCIS (Netherlands)

    Hong, S.-H.; Miller, T.W.; Tobin, H.; Borchers, B.; Hendrickx, J.M.H.; Lensen, H.A.; Schwering, P.B.W.

    2001-01-01

    Land mines are a major problem in many areas of the world. In spite of the fact that many different types of land mines sensors have been developed, the detection of non-metallic land mines remains very difficult. Most landmine detection sensors are affected by soil properties such as water content,

  8. 40 CFR 761.346 - Three levels of sampling.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Three levels of sampling. 761.346... PROHIBITIONS Sampling Non-Liquid, Non-Metal PCB Bulk Product Waste for Purposes of Characterization for PCB Disposal in Accordance With § 761.62, and Sampling PCB Remediation Waste Destined for Off-Site...

  9. 40 CFR 761.348 - Contemporaneous sampling.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Contemporaneous sampling. 761.348... PROHIBITIONS Sampling Non-Liquid, Non-Metal PCB Bulk Product Waste for Purposes of Characterization for PCB Disposal in Accordance With § 761.62, and Sampling PCB Remediation Waste Destined for Off-Site...

  10. Development of Solar Grade Silicon (SoG-Si) Feedstock by Recycling SoG-Si Wastes

    Energy Technology Data Exchange (ETDEWEB)

    Lifeng Zhang; Anping Dong; Lucas Nana Wiredu Damoah

    2013-01-24

    Experiment results of EM separation show that the non-metallic inclusions were successfully pushed to the boundary layer of the crucible under EM force. Larger frequency and smaller current generate smaller thickness of accumulated inclusions. More detailed EM separation experiments are undergoing to investigate the factors that affect the removal efficient of inclusions from SoG-Si

  11. Investigation of wear mechanism of tread during operation of railway wheels

    Directory of Open Access Journals (Sweden)

    Svetlana GUBENKO

    2012-01-01

    Full Text Available Causes of wear particles formation on railway wheels tread were investigated. Structural factors connecting with plastic deformation, formation of “white layer”, and also with non-metallic inclusions and corrosive products of wheel steel, defining wear of railway wheels tread during operation were fixed.

  12. 75 FR 49467 - Stainless Steel Sheet and Strip in Coils From Taiwan: Preliminary Results and Rescission in Part...

    Science.gov (United States)

    2010-08-13

    ...: grade, hot- or cold-rolled, gauge, surface finish, metallic coating, non-metallic coating, width, temper.... The product is manufactured by means of vacuum arc remelting, with inclusion controls for sulphide of... and 110 microns used to produce a metallic substrate with a honeycomb structure for use in automotive...

  13. Impact of soil water content on landmine detection using radar and thermal infared sensors

    NARCIS (Netherlands)

    Hong, S.-H.; Miller, T.W.; Tobin, H.; Borchers, B.; Hendrickx, J.M.H.; Lensen, H.A.; Schwering, P.B.W.

    2001-01-01

    Land mines are a major problem in many areas of the world. In spite of the fact that many different types of land mines sensors have been developed, the detection of non-metallic land mines remains very difficult. Most landmine detection sensors are affected by soil properties such as water content,

  14. Hydrolysis of epoxides and aziridines catalyzed by polymer-supported quarternary ammonium bisulfate

    Institute of Scientific and Technical Information of China (English)

    Wan Xuan Zhang; Kang Ye

    2008-01-01

    Macroporous resin (D201)-supported quartemary ammonium bisulfate (D201-HSO4)was prepared and effectively used in catalyzing the hydrolysis of epoxides or aziridines under mild and non-metal conditions to give the corresponding 1,2-diols and β-amino alcohols in high yields.The catalyst was facilely prepared and recyclable.

  15. 75 FR 816 - Identification of Additional Classes of Facilities for Development of Financial Responsibility...

    Science.gov (United States)

    2010-01-06

    ... defined as the extraction, beneficiation, or processing of metals (e.g., copper, gold, iron, lead, magnesium, molybdenum, silver, uranium, and zinc) and non-metallic, non-fuel minerals (e.g., asbestos... Materials Containing CERCLA Recycled oil/reclaimed copper; solvent 138 9.1 Hazardous Substances....

  16. Fusion materials semiannual progress report for period ending December 31, 1999

    Energy Technology Data Exchange (ETDEWEB)

    Burn, G.

    2000-03-01

    This is the twenty-seventh in a series of semiannual technical progress reports on fusion materials. This report combines the full spectrum of research and development activities on both metallic and non-metallic materials with primary emphasis on the effects of the neutronic and chemical environment on the properties and performance of materials for in-vessel components.

  17. Tapping the earth's geothermal resources: Hydrothermal today, magma tomorrow

    Energy Technology Data Exchange (ETDEWEB)

    Kukacka, L.E.

    1986-12-17

    The paper discusses geothermal resources, what it is, where it is, and how to extract energy from it. The materials research activities at Brookhaven National Laboratory related to geothermal energy extraction are discussed. These include high-temperature, light-weight polymer cements, elastomers, biochemical waste processing techniques, and non-metallic heat exchanger tubing. The economics of geothermal energy is also discussed. (ACR)

  18. Structure and Mechanical Properties of Ethylene-butene Copolymers

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The crystallinity of ethylene-butene copolymers prepared by copolymerization of ethylene and butene in the presence of a new highly active catalyst was studied by means of DSC, WAXD and DMA. The results show that the melting temperature, the crystallinity and the crystallite size decreased with increasing the content of butene in the copolymers. The copolymers have a high degree of branching, the butene segments are mainly in the amorphous regions of the copolymers, while the polyethylene sequence forms crystal phase acting as crosslinking bondage between the molecules at room temperature. The ethylene-butene copolymers have a low modulus, a low stress and a high strain analogous to the stress-strain behavior of non-cross thermoplastic elastomer.

  19. Mechanical properties and network structure of wheat gluten foams.

    Science.gov (United States)

    Blomfeldt, Thomas O J; Kuktaite, Ramune; Johansson, Eva; Hedenqvist, Mikael S

    2011-05-09

    This Article reports the influence of the protein network structure on the mechanical properties of foams produced from commercial wheat gluten using freeze-drying. Foams were produced from alkaline aqueous solutions at various gluten concentrations with or without glycerol, modified with bacterial cellulose nanosized fibers, or both. The results showed that 20 wt % glycerol was sufficient for plasticization, yielding foams with low modulus and high strain recovery. It was found that when fibers were mixed into the foams, a small but insignificant increase in elastic modulus was achieved, and the foam structure became more homogeneous. SEM indicated that the compatibility between the fibers and the matrix was good, with fibers acting as bridges in the cell walls. IR spectroscopy and SE-HPLC revealed a relatively low degree of aggregation, which was highest in the presence of glycerol. Confocal laser scanning microscopy revealed distinct differences in HMW-glutenin subunits and gliadin distributions for all of the different samples.

  20. Tensile properties and water absorption of zein sheets plasticized with oleic and linoleic acids.

    Science.gov (United States)

    Budi Santosa, F X; Padua, G W

    1999-05-01

    Corn zein has been investigated for fabrication of biodegradable packaging materials. Our objective was to investigate the effect of added plasticizers, oleic and linoleic acids, on tensile properties and water absorption of zein sheets. Moldable resins were precipitated from aqueous ethanol dispersions of zein and fatty acids and rolled into sheets of approximately 0.5 mm in thickness. To increase plasticization effects, zein-oleic acid sheets were replasticized by heating them in fatty acid baths. Plasticization resulted in flexible sheets of high clarity, low modulus, and high elongation and toughness, although low tensile strength. Water absorption of zein sheets was lowered by plasticization, attributed in part to reduced mass fraction of zein. Polymerization of linoleic acid may have sealed off pores on sheet surfaces, thus slowing water absorption.

  1. Reaction hot-pressing and property-composition relationships of modified sialon - boron nitride hetero-modulus ceramics

    Science.gov (United States)

    Wang, Y.; Shabalin, I. L.; Zhang, L.; Zhdanov, V. B.

    2011-10-01

    Hetero-modulus ceramics (HMC) present the combination of a ceramic matrix with inclusions of a dispersed phase with considerably lower values of Young's modulus, resulting in a material with significantly advanced properties. Densified '-Si6-xAlxOxN8-x based HMC materials, with various volume contents of low-modulus α-BN phase and modifiers such as TiN or ZrO2 in sialon matrix, were prepared by high-temperature reaction hot-pressing in nitrogen atmosphere. The pristine blend composition for reaction hot-pressing consisted of mixed fine powders of Si, Al, B, Ti nitrides and Al, Zr oxides. Statistical design of 25-2 fractional factorial and third-order simplex-grid types was used for the experimental studies to estimate the effects of some technological factors on the densification of hot-pressed products and the property-composition relationships of modified HMC materials.

  2. Influence of growth stresses and material properties on distortion of sawn timber - numerical investigation

    DEFF Research Database (Denmark)

    Johansson, Marie; Ormarsson, Sigurdur

    2009-01-01

    The board distortion that occurs during the sawing and the drying process causes major problems in the utilisation of sawn timber. The distortion is highly influenced by parameters such as spiral grain angle, modulus of elasticity, shrinkage, growth stresses and sawing pattern. In this study...... a finite element simulation of log sawing and timber drying was performed to study how these parameters interact to affect board distortion. A total of 81 logs with different material combinations were simulated. From each simulated log four boards with different annual ring orientation were studied....... The results showed that the elastic modulus, shrinkage coefficient and growth stresses had a large influence on the final bow and spring deformation. After sawing of the log into boards, the release of growth stresses was the main contributor to the bow and spring deformation. For boards with low modulus...

  3. A review of polymerization contraction: the influence of stress development versus stress relief.

    Science.gov (United States)

    Carvalho, R M; Pereira, J C; Yoshiyama, M; Pashley, D H

    1996-01-01

    The insertion of bonded resin composites into cavity preparations leads to a competition between polymerization contraction forces and the strength of bonds to tooth structure. The degree of stress development can be controlled, to some extent, by the cavity design (C-factor), the use of bases, the size, shape, and position of increments of composite resins placed in the cavity, and whether the resin is light- or chemically cured. Stress relief can be accomplished by maintaining the C-factor as low as possible, using chemical-curing resins, low modulus liners, and, over time, by water sorption. A thorough understanding of these principles permits clinicians to exercise more control over these variables, thereby improving the quality of their bonded restorations.

  4. Signal transduction of the physical environment in the neural differentiation of stem cells

    Science.gov (United States)

    Thompson, Ryan; Chan, Christina

    2016-01-01

    Neural differentiation is largely dependent on extracellular signals within the cell microenvironment. These extracellular signals are mainly in the form of soluble factors that activate intracellular signaling cascades that drive changes in the cell nucleus. However, it is becoming increasingly apparent that the physical microenvironment provides signals that can also influence lineage commitment and very low modulus surfaces has been repeatedly demonstrated to promote neurogenesis. The molecular mechanisms governing mechano-induced neural differentiation are still largely uncharacterized; however, a growing body of evidence indicates that physical stimuli can regulate known signaling cascades and transcription factors involved in neural differentiation. Understanding how the physical environment affects neural differentiation at the molecular level will enable research and design of materials that will eventually enhance neural stem cell (NSC) differentiation, homogeneity and specificity.

  5. Mechanics of finger-tip electronics.

    Science.gov (United States)

    Su, Yewang; Li, Rui; Cheng, Huanyu; Ying, Ming; Bonifas, Andrew P; Hwang, Keh-Chih; Rogers, John A; Huang, Yonggang

    2013-10-28

    Tactile sensors and electrotactile stimulators can provide important links between humans and virtual environments, through the sensation of touch. Soft materials, such as low modulus silicones, are attractive as platforms and support matrices for arrays sensors and actuators that laminate directly onto the fingertips. Analytic models for the mechanics of three dimensional, form-fitting finger cuffs based on such designs are presented here, along with quantitative validation using the finite element method. The results indicate that the maximum strains in the silicone and the embedded devices are inversely proportional to the square root of radius of curvature of the cuff. These and other findings can be useful in formulating designs for these and related classes of body-worn, three dimensional devices.

  6. Soft Gels with Ordered Iron Particles

    Science.gov (United States)

    An, Yuxian; Liu, Bo; Shaw, Montgomery T.

    For a number of years we and others have investigated electrorheological (ER) gel systems comprising low-modulus elastomers mixed with various particles. Unlike ER fluids, the particles in gels do not change relative positions, thus creating model systems that can be used to check equilibrium theories of ER response. To make such materials, a magnetic field was used to align iron particles during the cure of a liquid silicone prepolymer in a sheet mold. Particle chains were made with as little as 0.5% particles, and aligned at angles from 0 to 45° to the normal. The gap between the particles was controlled by swelling the crosslinked material with additional prepolymer. The dependence of the ER effect on particle structuring in these materials was investigated experimentally using rheometry and dielectrometry. Also investigated were the properties of these materials as transducers and actuators.

  7. Hard and Soft Multilayered SiCN Nanocoatings with High Hardness and Toughness

    Directory of Open Access Journals (Sweden)

    S. K. Mishra

    2013-01-01

    Full Text Available Alternate hard and soft layers increase deformation accommodation as thin hard layers slide relative to each other due to shear deformation of low modulus layers. However, the processing of such multilayers is challenging. In the present paper the alternating soft and hard multilayered SiCN coating deposited by magnetron sputtering has been studied and presented. A hardness and modulus of 37 GPa and 317 GPa with elastic recovery of 62% are achieved by alternate hard and soft layer of Si–C–N by magnetron sputtering. The trilayer films sustained even 2000 gf under indentation without failure though substrate plastically deformed. The fracture toughness value KIC was measured to be 9.5–10 MPa m1/2, significantly higher than many reported hard coatings.

  8. A New Self-Loading Locomotion Mechanism for Wall Climbing Robots Employing Biomimetic Adhesives

    Institute of Scientific and Technical Information of China (English)

    Amirpasha Peyvandi; Parviz Soroushian; Jue Lu

    2013-01-01

    A versatile locomotion mechanism is introduced and experimentally verified.This mechanism comprises four rectangular wheels (legs) with rotational phase difference which enables the application of pressure to each contacting surface for securing it to the surface using bio-inspired or pressure-sensitive adhesives.In this mechanism,the adhesives are applied to two rigid plates attached to each wheel via hinges incorporating torsional springs.The springs force the plates back to their original position after the contact with the surface is lost in the course of locomotion.The wheels are made of low-modulus elastomers,and the pressure applied during contact is controlled by the elastic modulus,geometry and phase difference of wheels.This reliable adhesion system does not rely upon gravity for adhering to surfaces,and provides the locomotion mechanism with the ability to climb walls and transition from horizontal to vertical surfaces.

  9. Mg amorphous alloys for biodegradable implants; Ligas amorfas de magnesio utilizadas em implantes consumiveis

    Energy Technology Data Exchange (ETDEWEB)

    Danez, G.P., E-mail: gabidanez@hotmail.co [Universidade Federal de Sao Carlos (PPG-CEMUFSCar), SP (Brazil). Programa de Pos-Graduacao em Ciencia e Engenharia de Materiais; Koga, G.Y.; Tonucci, S.; Bolfarini, C.; Kiminami, C.S.; Botta Filho, W.J. [Universidade Federal de Sao Carlos (DEMa/UFSCar), SP (Brazil). Dept. de Engenharia de Materiais

    2010-07-01

    The use of implants made from amorphous alloys magnesium-based with additions of zinc and calcium are promising. Properties such as biocompatibility, low density, high mechanical strength, low modulus (as compared to alloys such as stainless steel and titanium), corrosion resistance and wear resistance make it attractive for use in implants. Moreover, the by-products of corrosion and wear are not toxic and may contribute to fixation. Aiming to understand the tendency of this amorphous ternary (Mg-Zn-Ca) and expand the information about this system, this work involved the use of the topological criterion of instability ({lambda}) and the criterion of electronegativity ({Delta}e) to the choice of compositions. The alloys were processed into wedge-shaped and analyzed structurally and in X-ray diffraction and scanning electron microscopy. (author)

  10. Growth and surface characterization of TiNbZr thin films deposited by magnetron sputtering for biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Tallarico, D.A. [Federal University of Sao Carlos, Materials Science and Engineering Graduation Program, Via Washington Luis km 235, CEP 13565-905 Sao Carlos, SP (Brazil); Gobbi, A.L. [Brazilian Nanotechnology National Laboratory, Rua Giuseppe Máximo Scolfaro 10.000, CEP 13083-100 Campinas, SP (Brazil); Paulin Filho, P.I. [Federal University of Sao Carlos, Department of Materials Engineering, Via Washington Luis km 235, CEP 13565-905 Sao Carlos, SP (Brazil); Maia da Costa, M.E.H. [Pontifical Catholic University of Rio de Janeiro, Department of Physics, CEP 22451-900 Rio de Janeiro, RJ (Brazil); Nascente, P.A.P., E-mail: nascente@ufscar.br [Federal University of Sao Carlos, Department of Materials Engineering, Via Washington Luis km 235, CEP 13565-905 Sao Carlos, SP (Brazil)

    2014-10-01

    Low modulus of elasticity and the presence of non-toxic elements are important criteria for the development of materials for implant applications. Low modulus Ti alloys can be developed by designing β-Ti alloys containing non-toxic alloying elements such as Nb and Zr. Actually, most of the metallic implants are produced with stainless steel (SS) because it has adequate bulk properties to be used as biomaterials for orthopedic or dental implants and is less expensive than Ti and its alloys, but it is less biocompatible than them. The coating of this SS implants with Ti alloy thin films may be one alternative to improve the biomaterial properties at a relatively low cost. Sputtering is a physical deposition technique that allows the formation of nanostructured thin films. Nanostructured surfaces are interesting when it comes to the bone/implant interface due to the fact that both the surface and the bone have nanoscale particle sizes and similar mechanical properties. TiNbZr thin films were deposited on both Si(111) and stainless steel (SS) substrates. The TiNbZr/Si(111) film was used as a model system, while the TiNbZr/SS film might improve the biocompatibility and extend the life time of stainless steel implants. The morphology, chemical composition, Young's modulus, and hardness of the films were analyzed by atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray spectroscopy (EDS), and nanoindentation. - Highlights: • TiNbZr thin films were deposited on Si(111) and stainless steel (SS). • Their Young's modulus differences are within 5.3% and hardness 1.7%. • TiNbZr/SS film chemical composition remained almost constant with depth. • TiNbZr films presented nanostructured grains and low roughness for substrates. • TiNbZr/SS film hardness was about 100% greater than the SS substrate hardness.

  11. Deconvoluting chain heterogeneities from driven translocation through a nano-pore

    CERN Document Server

    Adhikari, Ramesh

    2014-01-01

    We study translocation dynamics of a driven compressible semi-flexible chain consisting of alternate blocks of stiff ($S$) and flexible ($F$) segments of size $m$ and $n$ respectively for different chain length $N$. The free parameters in the model are the bending rigidity $\\kappa_b$ which controls the three body interaction term, the elastic constant $k_F$ in the FENE (bond) potential between successive monomers, as well as the block lengths $m$ and $n$ and the repeat unit $p$ ($N=m_pn_p$). We demonstrate that the due to change in the entropic barrier and the inhomogeneous friction on the chain a variety of scenario are possible amply manifested in the incremental mean first passage time (IMFPT) or in the waiting time distribution of the translocating chain. These informations can be deconvoluted to extract information about the mechanical properties of the chain at various length scales and thus can be used to nanopore based methods to probe biomolecules, such as DNA, RNA and proteins.

  12. Advances in the microrheology of complex fluids.

    Science.gov (United States)

    Waigh, Thomas Andrew

    2016-07-01

    New developments in the microrheology of complex fluids are considered. Firstly the requirements for a simple modern particle tracking microrheology experiment are introduced, the error analysis methods associated with it and the mathematical techniques required to calculate the linear viscoelasticity. Progress in microrheology instrumentation is then described with respect to detectors, light sources, colloidal probes, magnetic tweezers, optical tweezers, diffusing wave spectroscopy, optical coherence tomography, fluorescence correlation spectroscopy, elastic- and quasi-elastic scattering techniques, 3D tracking, single molecule methods, modern microscopy methods and microfluidics. New theoretical techniques are also reviewed such as Bayesian analysis, oversampling, inversion techniques, alternative statistical tools for tracks (angular correlations, first passage probabilities, the kurtosis, motor protein step segmentation etc), issues in micro/macro rheological agreement and two particle methodologies. Applications where microrheology has begun to make some impact are also considered including semi-flexible polymers, gels, microorganism biofilms, intracellular methods, high frequency viscoelasticity, comb polymers, active motile fluids, blood clots, colloids, granular materials, polymers, liquid crystals and foods. Two large emergent areas of microrheology, non-linear microrheology and surface microrheology are also discussed.

  13. Wing Warping and Its Impact on Aerodynamic Efficiency

    Science.gov (United States)

    Loh, Ben; Jacob, Jamey

    2007-11-01

    Inflatable wings have been demonstrated in many applications such as UAVs, airships, and missile stabilization surfaces. A major concern presented by the use of an inflatable wing has been the lack of traditional roll control surfaces. This leaves the designer with several options in order to have control about the roll axis. Since inflatable wings have a semi-flexible structure, wing warping is the obvious solution to this problem. The current method is to attach servos and control linkages to external surface of the wing that results in variation of profile chamber and angle of attack from leading edge or trailing edge deflection. Designs using internal muscles will also be discussed. This creates a lift differential between the half-spans, resulting in a roll moment. The trailing edge on the other half-span can also be deflected in the opposite direction to increase the roll moment as well as to reduce roll-yaw coupling. Comparisons show that higher L/D ratios are possible than using traditional control surfaces. An additional benefit is the ability to perform symmetric warping to achieve optimum aerodynamic performance. Via warping alone, an arbitrary span can be warped such that it has the same aerodynamic characteristics as an elliptical planform. Comparisons between lifting line theory and test results will be presented.

  14. Unfolding DNA condensates produced by DNA-like charged depletants: A force spectroscopy study

    Science.gov (United States)

    Lima, C. H. M.; Rocha, M. S.; Ramos, E. B.

    2017-02-01

    In this work, we have measured, by means of optical tweezers, forces acting on depletion-induced DNA condensates due to the presence of the DNA-like charged protein bovine serum albumin (BSA). The stretching and unfolding measurements performed on the semi-flexible DNA chain reveal (1) the softening of the uncondensed DNA contour length and (2) a mechanical behavior strikingly different from those previously observed: the force-extension curves of BSA-induced DNA condensates lack the "saw-tooth" pattern and applied external forces as high as ≈80 pN are unable to fully unfold the condensed DNA contour length. This last mechanical experimental finding is in agreement with force-induced "unpacking" detailed Langevin dynamics simulations recently performed by Cortini et al. on model rod-like shaped condensates. Furthermore, a simple thermodynamics analysis of the unfolding process has enabled us to estimate the free energy involved in the DNA condensation: the estimated depletion-induced interactions vary linearly with both the condensed DNA contour length and the BSA concentration, in agreement with the analytical and numerical analysis performed on model DNA condensates. We hope that future additional experiments can decide whether the rod-like morphology is the actual one we are dealing with (e.g. pulling experiments coupled with super-resolution fluorescence microscopy).

  15. Innovative phased array ultrasonic inspection solution for large rotor shafts

    Energy Technology Data Exchange (ETDEWEB)

    Maes, G.; Devos, D.; Tremblay, P., E-mail: gmaes@zetec.com [Zetec, Ville de Quebec, Quebec (Canada)

    2016-05-15

    The increasing needs of energy production led to new rotor shaft designs with larger dimensions. A new generation of nuclear power plants is already being deployed worldwide with such heavy components. Their implementation requires new inspection tools in order to guarantee the public safety and to ensure the quality of these critical parts. Due to the long sound path, conventional ultrasonic (UT) techniques cannot provide adequate detectability of the reference reflectors required by the existing codes. Also, some standards require multiple angle beams to be applied in addition to the straight beam inspection, and this leads to long inspection times. This paper will address the implementation and validation of phased array (PA) UT techniques, using a semi-flexible 2D array probe, for the inspection of large mono-block rotor shaft forgings. It will show how the beam focusing and steering capabilities of phased array UT probes can be used to overcome the issues occurring with conventional UT probes. Results of acoustic beam simulation, as well as detectability measurements and data acquisitions on representative test specimens will be presented and compared with conventional UT performance. Various aspects of the hardware and software specification will be addressed, as well as the potential reduction of the total inspection time. (author)

  16. A Coarse-Grained DNA Model Parameterized from Atomistic Simulations by Inverse Monte Carlo

    Directory of Open Access Journals (Sweden)

    Nikolay Korolev

    2014-05-01

    Full Text Available Computer modeling of very large biomolecular systems, such as long DNA polyelectrolytes or protein-DNA complex-like chromatin cannot reach all-atom resolution in a foreseeable future and this necessitates the development of coarse-grained (CG approximations. DNA is both highly charged and mechanically rigid semi-flexible polymer and adequate DNA modeling requires a correct description of both its structural stiffness and salt-dependent electrostatic forces. Here, we present a novel CG model of DNA that approximates the DNA polymer as a chain of 5-bead units. Each unit represents two DNA base pairs with one central bead for bases and pentose moieties and four others for phosphate groups. Charges, intra- and inter-molecular force field potentials for the CG DNA model were calculated using the inverse Monte Carlo method from all atom molecular dynamic (MD simulations of 22 bp DNA oligonucleotides. The CG model was tested by performing dielectric continuum Langevin MD simulations of a 200 bp double helix DNA in solutions of monovalent salt with explicit ions. Excellent agreement with experimental data was obtained for the dependence of the DNA persistent length on salt concentration in the range 0.1–100 mM. The new CG DNA model is suitable for modeling various biomolecular systems with adequate description of electrostatic and mechanical properties.

  17. A Numerical Study on Wave Evolution in Interaction with Flexible Vegetation

    Science.gov (United States)

    Tahvildari, N.; Zeller, R. B.; Kaihatu, J. M.

    2016-02-01

    Coastal wetlands are among the natural features with capability to reduce storm damage. Previous numerical studies on wave dissipation effects of aquatic vegetation typically apply some simplifications to vegetation behavior and mostly ignore spectral wave evolution. For instance, vegetation elements are usually assumed rigid or semi-flexible. Similarly, despite laboratory experiments that confirm the evolution of wave spectra over vegetation fields, nonlinear wave-wave interactions are generally ignored and a bulk dissipative measure such as reduction in root-mean-square waveheight is examined. Inadequate representation of wave and vegetation characteristics in numerical models reduce their capability in accurate prediction of coastal processes. To address these shortcomings, a time-domain nonlinear numerical model based on the Boussinesq formulation is developed and coupled with an enhanced vegetation representation that accounts for arbitrary rigidity. The model is validated with laboratory experiments and a frequency-dependent vegetative drag coefficient is obtained. The coefficient is then incorporated in a frequency-domain model to investigate the combined effect of vegetative wave dissipation and nonlinear wave-wave interactions in modulating the surface wave spectra. The effect of vegetation parameters such as rigidity, stem density, and state of submergence on wave characteristics is examined and implications in vegetation benefits in wave energy dissipation are discussed.

  18. [Study on molecular chain morphology and chain parameters of konjac glucomannan].

    Science.gov (United States)

    Li, Bin; Xie, Bi-jun

    2003-11-01

    To study the molecular chain morphology and chain parameters of konjac glucomannan (KGM). Solution behavior was studied by using light scattering(LS), gel permeation chromatograph (GPC) and method of viscosity. The molecular morphology was observed directly by atom force microscope (AFM) and transmission electron microscope (TEM). The average molecular weight (Mw), root-mean-square ratio of gyration(1/2), second Viral coefficients (A2) and multi-disperse coefficients (Mw/Mn) are 1.04 x 10(6), 105.0 +/- 0.9 nm, (-1.59 +/- 0.28) x 10(-3) mol.mL.g-2 and (1.020 +/- 0.003) respectively; Mark-Houwink equation was established as [eta] = 5.96 x 10(-2) Mw0.73, the molecular chain parameters were as follows: ML = 982.82 nm-1, q = 27.93 nm, d = 0.74 nm, h = 0.26 nm, L = 1,054.11 nm. Both the result showed by direct observation and the deduction drawn by solution behavior confirmed that the KGM molecular is stentering semi-flexible linear chain without branch.

  19. Dynamics of membrane nanotubes coated with I-BAR

    Science.gov (United States)

    Barooji, Younes F.; Rørvig-Lund, Andreas; Semsey, Szabolcs; Reihani, S. Nader S.; Bendix, Poul M.

    2016-07-01

    Membrane deformation is a necessary step in a number of cellular processes such as filopodia and invadopodia formation and has been shown to involve membrane shaping proteins containing membrane binding domains from the IRSp53-MIM protein family. In reconstituted membranes the membrane shaping domains can efficiently deform negatively charged membranes into tubules without any other proteins present. Here, we show that the IM domain (also called I-BAR domain) from the protein ABBA, forms semi-flexible nanotubes protruding into Giant Unilamellar lipid Vesicles (GUVs). By simultaneous quantification of tube intensity and tubular shape we find both the diameter and stiffness of the nanotubes. I-BAR decorated tubes were quantified to have a diameter of ~50 nm and exhibit no stiffening relative to protein free tubes of the same diameter. At high protein density the tubes are immobile whereas at lower density the tubes diffuse freely on the surface of the GUV. Bleaching experiments of the fluorescently tagged I-BAR confirmed that the mobility of the tubes correlates with the mobility of the I-BAR on the GUV membrane. Finally, at low density of I-BAR the protein upconcentrates within tubes protruding into the GUVs. This implies that I-BAR exhibits strong preference for negatively curved membranes.

  20. Microrheology of active actin networks

    Science.gov (United States)

    Larsen, Travis H.; Furst, Eric M.

    2006-03-01

    To provide insight into the viscoelastic response of non-equilibrium, entangled semi-flexible polymeric networks, we study the model system of F-actin networks in the presence of active fragments of skeletal myosin. To characterize the microrheological response of this system, polystyrene microspheres of 1μm in diameter are suspended into the three-dimensional, entangled F-actin network and diffusing wave spectroscopy is used to measure the mean-squared displacement of the particles on timescales from 100ns to 10ms. Particle motion is a result of both random thermal forces and the dissipation of actin filament fluctuations caused by the interactions of the suspended motor proteins with the network. Upon addition of myosin, we observe an increase in the MSD of the tracer particles and a shift in the scaling--dependence with respect to lag time from t^3/4 to t^x, where 3/4 motor proteins cause the filaments to develop an apparent decreased persistence length at length scales longer than the crossover length. Finally, we demonstrate that the addition of the cross-linking protein, α-actinin, suppresses this ``active'' scaling behavior, while maintaining elevated probe particle diffusivity relative to the control.

  1. Visualization of pulsatile flow for magnetic nanoparticle based therapies

    Science.gov (United States)

    Wentzel, Andrew; Yecko, Philip

    2015-11-01

    Pulsatile flow of blood through branched, curved, stenosed, dilated or otherwise perturbed vessels is more complex than flow through a straight, uniform and rigid tube. In some magnetic hyperthermia and magnetic chemo-therapies, localized regions of magnetic nanoparticle laden fluid are deliberately formed in blood vessels and held in place by magnetic fields. The effect of localized magnetic fluid regions on blood flow and the effect of the pulsatile blood flow on such magnetic fluid regions are poorly understood and difficult to examine in vivo or by numerical simulation. We present a laboratory model that facilitates both dye tracer and particle imaging velocimetry (PIV) studies of pulsatile flow of water through semi-flexible tubes in the presence of localized magnetic fluid regions. Results on the visualization of flows over a range of Reynolds and Womersley numbers and for several different (water-based) ferrofluids are compared for straight and curved vessels and for different magnetic localization strategies. These results can guide the design of improved magnetic cancer therapies. Support from the William H. Sandholm Program of Cooper Union's Kanbar Center for Biomedical Engineering is gratefully acknowledged.

  2. ITINERARIOS DE LA BUENA ENSEÑANZA A PARTIR DE LOS RELATOS BIOGRÁFICOS DOCENTES

    Directory of Open Access Journals (Sweden)

    Zelmira Álvarez

    2010-01-01

    Full Text Available En la investigación cualitativa en educación, el enfoque biográfico y narrativo ha logrado su identidad propia. Siguiendo esta línea, se indaga aquí, por medio de entrevistas semi-flexibles, en las biografías de una selección de buenos docentes de la Facultad de Humanidades de la Universidad Nacional de Mar del Plata, Argentina. Éstos fueron identificados a través de cuestionarios semi-abiertos administrados a estudiantes avanzados de los Profesorados de esta Facultad. Del análisis de las conversaciones, se han seleccionado seis casos que confieren a sus recorridos de vida públicos y privados la acepción de itinerarios físicos o intelectuales. La interpretación de los datos transforma a estos relatos en historias de vida y sugiere el entretejido de las buenas prácticas con las trayectorias. Se construye así en la educación superior -donde la enseñanza en el aula es privada- un conocimiento local pero colegiado.

  3. Exploring large-scale phenomena in composite membranes through an efficient implicit-solvent model

    Science.gov (United States)

    Laradji, Mohamed; Kumar, P. B. Sunil; Spangler, Eric J.

    2016-07-01

    Several microscopic and mesoscale models have been introduced in the past to investigate various phenomena in lipid membranes. Most of these models account for the solvent explicitly. Since in a typical molecular dynamics simulation, the majority of particles belong to the solvent, much of the computational effort in these simulations is devoted for calculating forces between solvent particles. To overcome this problem, several implicit-solvent mesoscale models for lipid membranes have been proposed during the last few years. In the present article, we review an efficient coarse-grained implicit-solvent model we introduced earlier for studies of lipid membranes. In this model, lipid molecules are coarse-grained into short semi-flexible chains of beads with soft interactions. Through molecular dynamics simulations, the model is used to investigate the thermal, structural and elastic properties of lipid membranes. We will also review here few studies, based on this model, of the phase behavior of nanoscale liposomes, cytoskeleton-induced blebbing in lipid membranes, as well as nanoparticles wrapping and endocytosis by tensionless lipid membranes. Topical Review article submitted to the Journal of Physics D: Applied Physics, May 9, 2016

  4. DNA exit ramps are revealed in the binding landscapes obtained from simulations in helical coordinates.

    Directory of Open Access Journals (Sweden)

    Ignacia Echeverria

    2015-02-01

    Full Text Available DNA molecules are highly charged semi-flexible polymers that are involved in a wide variety of dynamical processes such as transcription and replication. Characterizing the binding landscapes around DNA molecules is essential to understanding the energetics and kinetics of various biological processes. We present a curvilinear coordinate system that fully takes into account the helical symmetry of a DNA segment. The latter naturally allows to characterize the spatial organization and motions of ligands tracking the minor or major grooves, in a motion reminiscent of sliding. Using this approach, we performed umbrella sampling (US molecular dynamics (MD simulations to calculate the three-dimensional potentials of mean force (3D-PMFs for a Na+ cation and for methyl guanidinium, an arginine analog. The computed PMFs show that, even for small ligands, the free energy landscapes are complex. In general, energy barriers of up to ~5 kcal/mol were measured for removing the ligands from the minor groove, and of ~1.5 kcal/mol for sliding along the minor groove. We shed light on the way the minor groove geometry, defined mainly by the DNA sequence, shapes the binding landscape around DNA, providing heterogeneous environments for recognition by various ligands. For example, we identified the presence of dissociation points or "exit ramps" that naturally would terminate sliding. We discuss how our findings have important implications for understanding how proteins and ligands associate and slide along DNA.

  5. DNA exit ramps are revealed in the binding landscapes obtained from simulations in helical coordinates.

    Science.gov (United States)

    Echeverria, Ignacia; Papoian, Garegin A

    2015-02-01

    DNA molecules are highly charged semi-flexible polymers that are involved in a wide variety of dynamical processes such as transcription and replication. Characterizing the binding landscapes around DNA molecules is essential to understanding the energetics and kinetics of various biological processes. We present a curvilinear coordinate system that fully takes into account the helical symmetry of a DNA segment. The latter naturally allows to characterize the spatial organization and motions of ligands tracking the minor or major grooves, in a motion reminiscent of sliding. Using this approach, we performed umbrella sampling (US) molecular dynamics (MD) simulations to calculate the three-dimensional potentials of mean force (3D-PMFs) for a Na+ cation and for methyl guanidinium, an arginine analog. The computed PMFs show that, even for small ligands, the free energy landscapes are complex. In general, energy barriers of up to ~5 kcal/mol were measured for removing the ligands from the minor groove, and of ~1.5 kcal/mol for sliding along the minor groove. We shed light on the way the minor groove geometry, defined mainly by the DNA sequence, shapes the binding landscape around DNA, providing heterogeneous environments for recognition by various ligands. For example, we identified the presence of dissociation points or "exit ramps" that naturally would terminate sliding. We discuss how our findings have important implications for understanding how proteins and ligands associate and slide along DNA.

  6. First Electrical Characterization of Prototype 600 A HTS Twisted-pair Cables at Different Temperatures

    CERN Document Server

    Yang, Y; Bailey, W; Beduza, C; Ballarino, A

    2012-01-01

    Following the development of twisted-pair cables prepared with High Temperature Superconducting (HTS) tapes and their initial tests at 4.2 K in liquid helium at CERN, the cable samples of 2 m lengths were subsequently tested in flowing helium gas at temperatures between 10 K and 77 K at University of Southampton. A cryostat with optimized hybrid HTS current leads was purposely built for the tests up to 2.5 kA. The cryostat has two separate helium flow conduits, each accommodating a twisted pair and allowing independent temperature control. With the completion of the tests on the twisted-pair cables, a 5 m long semi-flexible Nexans cryostat was also set up for the testing of prototype HTS links assembled at CERN. The link, which is optimized for application to the remote powering of LHC 600 A electrical circuits, consists of a compact multi-cable assembly with up to 25 twisted-pair 600 A HTS tapes. The cables are cooled by a forced-flow of helium gas the inlet temperature of which can be changed in order to co...

  7. Shape optimization of self-avoiding curves

    Science.gov (United States)

    Walker, Shawn W.

    2016-04-01

    This paper presents a softened notion of proximity (or self-avoidance) for curves. We then derive a sensitivity result, based on shape differential calculus, for the proximity. This is combined with a gradient-based optimization approach to compute three-dimensional, parameterized curves that minimize the sum of an elastic (bending) energy and a proximity energy that maintains self-avoidance by a penalization technique. Minimizers are computed by a sequential-quadratic-programming (SQP) method where the bending energy and proximity energy are approximated by a finite element method. We then apply this method to two problems. First, we simulate adsorbed polymer strands that are constrained to be bound to a surface and be (locally) inextensible. This is a basic model of semi-flexible polymers adsorbed onto a surface (a current topic in material science). Several examples of minimizing curve shapes on a variety of surfaces are shown. An advantage of the method is that it can be much faster than using molecular dynamics for simulating polymer strands on surfaces. Second, we apply our proximity penalization to the computation of ideal knots. We present a heuristic scheme, utilizing the SQP method above, for minimizing rope-length and apply it in the case of the trefoil knot. Applications of this method could be for generating good initial guesses to a more accurate (but expensive) knot-tightening algorithm.

  8. Hydrodynamic characterisation of chitosan and its interaction with two polyanions: DNA and xanthan.

    Science.gov (United States)

    Almutairi, Fahad M; Erten, Tayyibe; Adams, Gary G; Hayes, Maria; McLoughlin, Pádraig; Kök, M Şamil; Mackie, Alan R; Rowe, Arthur J; Harding, Stephen E

    2015-05-20

    Chitosan, a soluble polycationic derivative of insoluble chitin, has been widely considered for use in the food, cosmetic and pharmaceutical industries. Commercial ("C") and in-house laboratory ("L") prepared chitosan samples extracted from crustaceous shells with different molecular weight and degrees of acetylation (25% and 15%) were compared with regards to (i) weight-average molecular weight (Mw); (ii) sedimentation coefficient (s(o)(20,w)) distribution, and (iii) intrinsic viscosity ([η]). These parameters were estimated using a combination of analytical ultracentrifugation (AUC), size exclusion chromatography coupled to multi-angle laser light scattering (SEC-MALS) and differential pressure viscometry. Polydisperse distributions were seen from sedimentation coefficient distributions and elution profiles from SEC-MALS. Mw values obtained for each sample by sedimentation equilibrium measurements were in excellent agreement with those obtained from SEC-MALS. Mark-Houwink-Kuhn-Sakurada (MHKS) and Wales van Holde analyses of the data all suggest a semi-flexible conformation. The principle of co-sedimentation was then used to monitor the interactions of the two different molecular weights of L chitosans with two polyanions, DNA and xanthan (another double helical high molecular weight molecule). Interactions were clearly observed and then quantified from the changes in the sedimentation coefficient distribution of the mixture compared to unmixed controls using sedimentation velocity. The interactions appeared to show a strong dependence on molecular weight. The relevance of this for DNA condensation applications is indicated. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Polyamide as a Denture Base Material: A Literature Review

    Directory of Open Access Journals (Sweden)

    Mahroo Vojdani

    2015-03-01

    Full Text Available The purpose of this article was to review the biocompatibility, physical, and mechanical properties of the polyamide denture base materials. An electronic search of scientific papers from 1990-2014 was carried out using PubMed, Scopus and Wiley Inter Science engines using the search terms “nylon denture base” and “polyamide denture base”. Searching the key words yielded a total of 82 articles. By application of inclusion criteria, the obtained results were further reduced to 24 citations recruited in this review. Several studies have evaluated various properties of polyamide (nylon denture base materials. According to the results of the studies, currently, thermo-injectable, high impact, flexible or semi-flexible polyamide is thought to be an alternative to the conventional acrylic resins due to its esthetic and functional characteristics and physicochemical qualities. It would be justifiable to use this material for denture fabrication in some cases such as severe soft/ hard tissue undercuts, unexplained repeated fracture of denture, in aesthetic-concerned patients, those who have allergy to other denture base materials, and in patients with microstomia. Although polyamide has some attractive advantages, they require modifications to produce consistently better properties than the current polymethyl methacrylate (PMMA materials. Moreover, since there is a very limited knowledge about their clinical performance, strict and careful follow-up evaluation of the patients rehabilitated with polyamide prosthesis is recommended.

  10. A unified approach to computation of solid and liquid free energy to revisit the solid-fluid equilibrium of Lennard-Jones chains.

    Science.gov (United States)

    Vorselaars, Bart

    2015-03-21

    Liquid free energies are computed by integration along a path from a reference system of known free energy, using a strong localization potential. A particular choice of localization pathway is introduced, convenient for use in molecular dynamics codes, and which achieves accurate results without the need to include the identity-swap or relocation Monte Carlo moves used in previous studies. Moreover, an adaptive timestep is introduced to attain the reference system. Furthermore, a center-of-mass correction that is different from previous studies and phase-independent is incorporated. The resulting scheme allows computation of both solid and liquid free energies with only minor differences in simulation protocol. This is used to re-visit solid-liquid equilibrium in a system of short semi-flexible Lennard-Jones chain molecules. The computed melting curve is demonstrated to be consistent with direct co-existence simulations and computed hysteresis loops, provided that an entropic term arising from unsampled solid states is included.

  11. Polyamide as a Denture Base Material: A Literature Review

    Science.gov (United States)

    Vojdani, Mahroo; Giti, Rashin

    2015-01-01

    The purpose of this article was to review the biocompatibility, physical, and mechanical properties of the polyamide denture base materials. An electronic search of scientific papers from 1990-2014 was carried out using PubMed, Scopus and Wiley Inter Science engines using the search terms “nylon denture base” and “polyamide denture base”. Searching the key words yielded a total of 82 articles. By application of inclusion criteria, the obtained results were further reduced to 24 citations recruited in this review. Several studies have evaluated various properties of polyamide (nylon) denture base materials. According to the results of the studies, currently, thermo-injectable, high impact, flexible or semi-flexible polyamide is thought to be an alternative to the conventional acrylic resins due to its esthetic and functional characteristics and physicochemical qualities. It would be justifiable to use this material for denture fabrication in some cases such as severe soft/ hard tissue undercuts, unexplained repeated fracture of denture, in aesthetic-concerned patients, those who have allergy to other denture base materials, and in patients with microstomia.  Although polyamide has some attractive advantages, they require modifications to produce consistently better properties than the current polymethyl methacrylate (PMMA) materials. Moreover, since there is a very limited knowledge about their clinical performance, strict and careful follow-up evaluation of the patients rehabilitated with polyamide prosthesis is recommended. PMID:26106628

  12. Design, fabrication, test, and qualification and price analysis of third generation design solar cell modules

    Science.gov (United States)

    Shepard, N. F.

    1980-03-01

    The Block 4 shingle type module makes it possible to apply a photovoltaic array to the sloping roof of a residential building by simply nailing the overlapping hexagon shaped shingles to the plywood roof sheathing. This third-generation shingle module design consists of nineteen series connected 100 mm diameter solar cells which are arranged in a closely packed hexagon configuration to provide in excess of 75 watts/sq m of exposed module area under standard operating conditions. The solar cells are individually bonded to the embossed underside of a 4.4 mm thick thermally tempered piece of glass. An experimental silicone pottant was used as the transparent bonding adhesive between the cells and glass. The semi-flexible portion of each shingle module is a composite laminate construction consisting of an outer layer of FLEXSEAL bonded to an inner core of closed cell polyethylene foam. Silaprene is used as the substrate laminating adhesive. The module design has satisfactorily survived qualification testing program which includes 50 thermal cycles between -40 and +90 C, a seven day temperature-humidity exposure test, and a wind resistance test.

  13. Physical deposition behavior of stiff amphiphilic polyelectrolytes in an external electric field

    Science.gov (United States)

    Hu, Dongmei; Zuo, Chuncheng; Cao, Qianqian; Chen, Hongli

    2017-08-01

    Coarse-grained molecular dynamics simulations are conducted to study the physical deposition behavior of stiff amphiphilic polyelectrolytes (APEs) in an external electric field. The effects of chain stiffness, the charge distribution of a hydrophilic block, and electric field strength are investigated. Amphiphilic multilayers, which consist of a monolayer of adsorbed hydrophilic monomers (HLMs), a hydrophobic layer, and another hydrophilic layer, are formed in a selective solvent. All cases exhibit locally ordered hydrophilic monolayers. Two kinds of hydrophobic micelles are distinguished based on local structures. Stripe and network hydrophobic patterns are formed in individual cases. Increasing the chain stiffness decreases the thickness of the deposited layer, the lateral size of the hydrophobic micelles, and the amount of deposition. Increasing the number of positively charged HLMs in a single chain has the same effect as increasing chain stiffness. Moreover, when applied normally to the substrate, the electric field compresses the deposited structures and increases the amount of deposition by pulling more PEs toward the substrate. A stronger electric field also facilitates the formation of a thinner and more ordered hydrophilic adsorption layer. These estimates help us explore how to tailor patterned nano-surfaces, nano-interfaces, or amphiphilic nanostructures by physically depositing semi-flexible APEs which is of crucial importance in physical sciences, life sciences and nanotechnology.

  14. Recent advances with generalized entropy theory of glass-formation in polymers

    Science.gov (United States)

    Freed, Karl

    The generalized entropy theory (GET) of glass-formation in polymers is a combination of the lattice cluster theory (LCT) for the configurational entropy density with the Adam-Gibbs (AG) theory for the structural relaxation time. A greatly simplified form of the GET (whose expression for the free energy is roughly double that of Flory-Huggins theory) accurately reproduces the four characteristic temperatures of glass-formation (the onset, crossover, glass transition, and Kauzmann temperatures) of the full GET to within 4K for a series of models of polymers composed of semi-flexible chains having the structure of poly(n-alpha olefins). The theory is now simple enough to be used in courses in polymer physics. Although the successes of the GET provide a strong validation of the final form of the AG theory provided the configurational entropy is used, the physical basis of the AG theory has remained an enigma. Hence, we have developed a new, more general, statistical mechanical derivation of AG theory that explains the previously perplexing observations that the string-like elementary excitations have the mass and temperature dependence of systems undergoing equilibrium self-assembly. This work is supported by the (U.S.) Department of Energy (DOE), Office of Basic Energy Sciences, Division of Materials Sciences and Engineering under Award No. DE- SC0008631.

  15. Mechanical models of the cellular cytoskeletal network for the analysis of intracellular mechanical properties and force distributions: a review.

    Science.gov (United States)

    Chen, Ting-Jung; Wu, Chia-Ching; Su, Fong-Chin

    2012-12-01

    The cytoskeleton, which is the major mechanical component of cells, supports the cell body and regulates the cellular motility to assist the cell in performing its biological functions. Several cytoskeletal network models have been proposed to investigate the mechanical properties of cells. This review paper summarizes these models with a focus on the prestressed cable network, the semi-flexible chain network, the open-cell foam, the tensegrity, and the granular models. The components, material parameters, types of connection joints, tension conditions, and the advantages and disadvantages of each model are evaluated from a structural and biological point of view. The underlying mechanisms that are associated with the morphological changes of spreading cells are expected to be simulated using a cytoskeletal model; however, it is still paid less attention most likely due to the lack of a suitable cytoskeletal model that can accurately model the spreading process. In this review article, the established cytoskeletal models are hoped to provide useful information for the development of future cytoskeletal models with different degrees of cell attachment for the study of the mechanical mechanisms underlying the cellular behaviors in response to external stimulations.

  16. Development and testing of shingle-type solar cell modules. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Shepard, N.F.

    1979-02-28

    The design, development, fabrication and testing of a shingle-type terrestrial solar cell module which produces 98 watts/m/sup 2/ of exposed module area at 1 kW/m/sup 2/ insolation and 61/sup 0/C are reported. These modules make it possible to easily incorporate photovoltaic power generation into the sloping roofs of residential or commercial buildings by simply nailing the modules to the plywood roof sheathing. This design consists of nineteen series-connected 53 mm diameter solar cells arranged in a closely packaged hexagon configuration. These cells are individually bonded to the embossed surface of a 3 mm thick thermally tempered hexagon-shaped piece of ASG SUNADEX glass. Monsanto SAFLEX polyvinyl butyral is used as the laminating adhesive. RTVII functions as the encapsulant between the underside of the glass superstrate and a rear protective sheet of 0.8 mm thick TEXTOLITE. The semi-flexible portion of each shingle module is a composite laminate construction consisting of outer layers of B.F. Goodrich FLEXSEAL and an epichlorohydrin closed cell foam core. The module design has satisfactorily survived the JPL-defined qualification testing program which includes 50 thermal cycles between -40 and +90/sup 0/C, a seven-day temperature-humidity exposure test and a mechanical integrity test consisting of a bidirectional cyclic loading at 2390 Pa (50 lb/ft/sup 2/) which is intended to simulate loads due to a 45 m/s (100 mph) wind.

  17. Computer aided design of free-machinability prehardened mold steel for plastic

    Institute of Scientific and Technical Information of China (English)

    HE Yan-lin; LI Lin; GAO Wen; WANG Qing-liang; WU Xiao-chun

    2005-01-01

    In order to improve the machinability but not to impair other properties of the prehardened mold steel for plastic, the composition was designed by application of Thermo-Calc software package to regulate the type of nonmetallic inclusion formed in the steel. The regulated non-metallic inclusion type was also observed by SEM and EDX. Then the maehinability assessment of the steel with designed composition under different conditions was studied by the measurement of tool wear amount and cutting force. The results show that the composition of free cutting elements adding to mold steel for plastic can be optimized to obtain proper type of non-metallic inclusion in the aid of Thermo-Calc, compared with the large volume fraction of soft inclusion which is needed for promoting ductile fracture at low cutting speeds, the proper type of inclusion at high cutting speeds is glassy oxide inclusion. All those can be obtained in the present work.

  18. Natural Radioactivity in Building Materials and Its Harm%建筑材料的天然放射性及其危害

    Institute of Scientific and Technical Information of China (English)

    赵琼慧

    2015-01-01

    建筑材料分为无机非金属建筑主体材料和无机非金属装修材料,通过检测结果,证明建筑材料中所含的长寿命天然放射性核素会放射α、γ射线,直接对室内构成内、外照射危害,从而对人体造成健康危害,因此不容忽视。%Building materials are divided into inorganic non-metallic building main body materials and inorganic non-metallic decoration materials,building materials in the long life of radioactive nuclide radiation alpha and gamma rays,directly to indoor constitute the internal and external exposure hazards,to cause a health hazard to human body,therefore,it should not be ignored.

  19. Evaluating the effectiveness of heat-resistant cast steel filtration from the results of structure examinations

    Directory of Open Access Journals (Sweden)

    Asłanowicz M.

    2007-01-01

    Full Text Available Filtration guarantees castings characterised by high quality and free from any non-metallic inclusions, which are formed at the stage of melting and pouring of liquid metal. This article discusses the problem of the effectiveness of filtration process taking as an example heat-resistant cast steel poured into ceramic moulds. In investigations, foamed zircon filters made by FerroTerm Sp. z o.o. The effectiveness of filtration was described and examined using the results of metallographic examinations, including macro- and micro-structure examinations of metal and of cast metal/ceramic filter interface, and measurements of the content of non-metallic inclusions. The methods of investigations were presented, the obtained results were described, and relevant conclusions were drawn, all of them unmistakably indicating a very beneficial effect that filtration has on molten metal quality. Łódź, Poland, were used.

  20. Wide – Ranging Influence of Mischmetal on Properties of GP240GH Cast Steel

    Directory of Open Access Journals (Sweden)

    J. Kasińska

    2012-12-01

    Full Text Available This paper presents influence of rare earth metals (REM on the properties of GP240GH cast carbon steel. The research has beenperformed on successive industrial melts. Each time ca 2000 kg of liquid metal was modified. The rare earth metals were put into the ladle during tapping of heat melt from the furnace. Because of this the amount of sulphur in the cast steel was decreased and the non-metallic inclusion morphology was significantly changed. It was found that non metallic inclusions the cracking mechanism of Charpy specimens and the impact strength were all changed. The following properties were tested: mechanical properties (y, UTS, plastic properties (necking, elongation and impact strength (SCI. In the three-point bend test the KJC stress intensity factor was evaluated.

  1. Wide – Ranging Influence of Mischmetal on Properties of GP240GH Cast Steel

    Directory of Open Access Journals (Sweden)

    Kasińska J.

    2012-12-01

    Full Text Available This paper presents influence of rare earth metals (REM on the properties of GP240GH cast carbon steel. The research has been performed on successive industrial melts. Each time ca 2000 kg of liquid metal was modified. The rare earth metals were put into the ladle during tapping of heat melt from the furnace. Because of this the amount of sulphur in the cast steel was decreased and the non-metallic inclusion morphology was significantly changed. It was found that non metallic inclusions the cracking mechanism of Charpy specimens and the impact strength were all changed. The following properties were tested: mechanical properties (σy, σUTS, plastic properties (necking, elongation and impact strength (SCI. In the three-point bend test the KJC stress intensity factor was evaluated.

  2. Analysis of oxide inclusions in steel by fast laser-induced breakdown spectroscopy scanning: an approach to quantification.

    Science.gov (United States)

    Boué-Bigne, F

    2007-03-01

    Laser-induced breakdown spectroscopy (LIBS) measurements were performed on a steel sample to investigate the feasibility of obtaining fast information on cleanness. A calibration approach was considered to enable the quantification of the elemental composition of non-metallic inclusions; the same data was also used to estimate the size of the inclusions. For the first time, the quantified chemical composition data obtained by LIBS for non-metallic inclusions was compared to the corresponding results obtained from scanning electron microscopy-energy dispersive X-ray (SEM-EDX) analysis, the conventional method used for steel cleanness assessment, and proved successful. Due to the speed of analysis and the systematic recording of the signal from the scanned area, LIBS enables the analysis of larger areas of sample and in significantly shorter time than with automated SEM-EDX. This paper summarizes the hitherto obtained results for the fast analysis of inclusions in steel by LIBS.

  3. Advanced Doppler radar physiological sensing technique for drone detection

    Science.gov (United States)

    Yoon, Ji Hwan; Xu, Hao; Garcia Carrillo, Luis R.

    2017-05-01

    A 24 GHz medium-range human detecting sensor, using the Doppler Radar Physiological Sensing (DRPS) technique, which can also detect unmanned aerial vehicles (UAVs or drones), is currently under development for potential rescue and anti-drone applications. DRPS systems are specifically designed to remotely monitor small movements of non-metallic human tissues such as cardiopulmonary activity and respiration. Once optimized, the unique capabilities of DRPS could be used to detect UAVs. Initial measurements have shown that DRPS technology is able to detect moving and stationary humans, as well as largely non-metallic multi-rotor drone helicopters. Further data processing will incorporate pattern recognition to detect multiple signatures (motor vibration and hovering patterns) of UAVs.

  4. Design of the Shell Nosing Fixture for Self-locking Nuts%自锁螺母收口夹具的设计

    Institute of Scientific and Technical Information of China (English)

    王国平

    2012-01-01

    针对非金属嵌件自锁螺母收口时容易产生裂纹、非金属嵌件滑动等质量问题,基于多年加工实践经验,设计了自锁螺母收口夹具,有效地解决了自锁螺母的加工问题.该设计有很强的实用价值.%Because the self-locking nuts with non-metallic insert were easy to produce crack in the process of shell nosing and the slide of non-metallic insert quality problems, the shell nosing fixture of self-locking nuts was designed based on man-y years of machining practical experiences. The machining problems of the self-locking nuts were solved effectively.

  5. Working group 3: upstream pipelines: inspection, corrosion and integrity management

    Energy Technology Data Exchange (ETDEWEB)

    Paez, Jorge; Stephenson, Mark [Talisman Energy, (Canada)

    2011-07-01

    The third topic investigated the latest challenges to upstream pipeline operation and the areas for improvement in upstream integrity in the pipeline industry. The first session of talks reported on the pipeline incident analysis conducted by the CAPP on several companies from 2006 to 2010 in order to identify best management practises and to drive improvement in pipeline integrity management. Reviews of primary failure statistics and failure frequency were conducted with respect to the various materials of pipes. A summary of changes to the CSA standard related to non-metallic pipes was also presented to complete this background overview of the upstream industry. The second session provided more information about these non-metallic pipes, focusing on construction and quality issues with large diameter HDPE pipelines. The third session discussed the ERW pipeline in relation to upstream industry. An integrity management panel discussion was carried out to close this third working group.

  6. A Study on contact drying with flexible screen

    Institute of Scientific and Technical Information of China (English)

    陆仁书; 王伟宏; 花军

    2000-01-01

    Three types of material as platen in contact drying process were tested in Composition Board Laboratory of Northeast Forestry University in 1998. Poplar veneers were dried under 0.3 MPa at 160℃ or 180℃. Through comparison a non-metal flexible material was chosen as screen for designing contact dryer and replacing curved metal plate. The new type contact dryer solved the problem of long auxiliary time by loading wet veneers into press and unloading dried veneers out of press at the same time. This increased productivity. Veneer’s moisture content (MC) varied with drying time in index law. The process of contact drying with non-metal flexible screen was analyzed by stages of preheating, high-speed drying, retarded drying and extremely slow drying.

  7. Advances in atomic spectroscopy

    CERN Document Server

    Sneddon, J

    1997-01-01

    This series describes selected advances in the area of atomic spectroscopy. It is primarily intended for the reader who has a background in atmoic spectroscopy; suitable to the novice and expert. Although a widely used and accepted method for metal and non-metal analysis in a variety of complex samples, Advances in Atomic Spectroscopy covers a wide range of materials. Each Chapter will completely cover an area of atomic spectroscopy where rapid development has occurred.

  8. NASA-STD-6016 Standard Materials and Processes Requirements for Spacecraft

    Science.gov (United States)

    Hirsch, David B.

    2009-01-01

    The standards for materials and processes surrounding spacecraft are discussed. Presentation focused on minimum requirements for Materials and Processes (M&P) used in design, fabrication, and testing of flight components for NASA manned, unmanned, robotic, launch vehicle, lander, in-space and surface systems, and spacecraft program/project hardware elements.Included is information on flammability, offgassing, compatibility requirements, and processes; both metallic and non-metallic materials are mentioned.

  9. Gibbs free energy and conditions of spinel (MgO-Al{sub 2}O{sub 3}) formation in liquid steel

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, H. [Kuzuu Works, Yoshizawa Lime Industry, Kuzuu-machi (Japan); Fujii, K. [Aishin AW Co. Ltd., Anjo (Japan); Nagasaka, T.; Hino, M. [Dept. of Metallurgy, Graduate School of Engineering, Tohoku Univ., Sendai (Japan)

    2003-02-01

    The formation conditions of spinel non-metallic inclusion during deoxidation with aluminum in secondary refining furnace with MgO lining were discussed in the present work. The thermodynamic data of deoxidation equilibrium with magnesium, calcium and aluminum in liquid iron were determined by the authors. The activities of oxygen and dissolved deoxidizer were evaluated in the thermodynamic description by the first and second order interaction parameters including the cross product terms. (orig.)

  10. Revised Safety Instruction 41 (IS41 REV.)

    CERN Multimedia

    SC Secretariat

    2005-01-01

    Please note that the Revised Safety Instruction No. 41 (IS41 REV.), entitled 'The use of plastic and other non-metallic materials at CERN with respect to fire safety and radiation resistance' is available on the web at the following url: https://edms.cern.ch/document/335806/LAST_RELEASED Paper copies can also be obtained from the SC Unit Secretariat, e-mail: sc.secretariat@cern.ch SC Secretariat

  11. MINING INDUSTRY IN CROATIA

    Directory of Open Access Journals (Sweden)

    Slavko Vujec

    1996-12-01

    Full Text Available The trends of World and European mine industry is presented with introductory short review. The mining industry is very important in economy of Croatia, because of cover most of needed petroleum and natural gas quantity, total construction raw materials and industrial non-metallic raw minerals. Detail quantitative presentation of mineral raw material production is compared with pre-war situation. The value of annual production is represented for each raw mineral (the paper is published in Croatian.

  12. Development of Diamond-Coated Drills

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Compared with the sintered polycrystalline diamond, the deposited thin film diamond has the great advantage on the fabrication of cutting tools with complex geometries such as drills. Because of their low costs for fabrication equipment and high performance on high speed machining non-ferrous metals and alloys, metal-compound materials, and hard brittle non-metals, diamond-coated drills find great potentialities in the commercial application. However, the poor adhesion of the diamond film on the substrate...

  13. Defense Small Business Innovation Research Program (SBIR). Volume 1. Army Abstracts of Phase 1 Awards 1991

    Science.gov (United States)

    1991-01-01

    CURRENTLY IS DEVELOPING SEVERAL NOVEL ENZYMES FOR INDUSTRIAL MARKETS USING NEWLY ISOLATED BACTERIA , INCLUDING ONE PROCESS IN PILOT SCALE PRODUCTION...THE PROPOSED EFFORT WILL EXTEND UPON THIS PREVIOUS WORK iN NON-METALLIC MINE DETECTION. PERCEPTUAL IMAGES Topic#: 91-139 wD. 91tED 15951 LOS GATOS ...BLVD, SUITE 7 Office: ETDL LOS GATOS , CA 95032 Contract #: Phone: (408) 356-4562 PI: JOHN L. MILLER Title: ANALYSIS OF A FLAT PANEL AUTOSTEREOSCOPIC

  14. Using Isothermal Microcalorimetry to Determine Compatibility of Structural Materials with High Test Hydrogen Peroxide (HTP) Propellant

    Science.gov (United States)

    Gostowski, Rudy; Villegas, Yvonne; Nwosisi, Genne

    2003-01-01

    High-Test Hydrogen Peroxide (HTP) propellant (greater than or equal to 70%) offers many advantages in space launch applications; however, materials used in construction of propulsion systems must be shown to be compatible with HTP. Isothermal Microcalorimetry (IMC) was used to determine the compatibility of several metallic and non-metallic materials with 90% HTP. The results of these experiments agreed with those from immersion bath tests when the values were converted to %Active Oxygen Loss per week (%AOL/wk).

  15. Using Isothermal Microcalorimetry to Determine Compatibility of Structural Materials with High-Test Hydrogen Peroxide (HTP) Propellant

    Science.gov (United States)

    Gostowski, Rudy; Villegas, Yvonne; Nwosisi, Genne; Rodgers, Stephen L. (Technical Monitor)

    2002-01-01

    High-Test Hydrogen Peroxide (HTP) propellant (equal to or greater than 70%) offers many advantages in space launch applications. However, materials used in construction of propulsion systems must be shown to be compatible with HTP. Isothermal Microcalorimetry (IMC) was used to determine the compatibility of several metallic and non-metallic materials with 90% HTP. The results of these experiments agreed with those from immersion bath tests when the values were converted to % Active Oxygen Loss per week (%AOL/wk).

  16. Thermodynamic study and modelling of iron-based melts for adequate prediction of modern ladle metallurgy processes

    Science.gov (United States)

    Zaitsev, A. I.; Rodionova, I. G.; Shaposhnikov, N. G.; Zemlyanko, O. A.; Karamisheva, N. A.

    2008-02-01

    The representation of iron-based melts as associated liquids have been developed basing on the detail experimental investigation and analysis of available data on their thermodynamic properties and phase equilibria. It has allowed, for the first time, to interpret adequately the reactivity of the earth metals in the iron-based melts and to predict with high precision the reactions of metal refinement and non-metallic inclusions modifying in modern ladle metallurgy.

  17. The Utilization of Advanced Composites in Military Aircraft Held in San Diego, California on 7-11 October 1991 (L’Emploi des Materiaux Composites de Pointe pour les Avions Militaires)

    Science.gov (United States)

    1992-04-01

    performed with: P = C.05 Tes!: Frequency x 2.5 Fz. rLL r Design Limit LA U S Fiq.l0 LOAD S1KIR[CIRM F’OR IATIGU[ TESI I.2-II COMPRESSION :1I:T:AL Bt,’C...Aerospace Series, Fluids for Assessment of Non-Metallic Materials. :3. ISO 1817 Rubber, Vulcanized -Effect of Liquids. 13-4 FLUID INTERACTIONS a7 0 6

  18. The status of the Delft University Neutron Backscatter Landmine Detector (DUNBLAD).

    Science.gov (United States)

    Bom, V R; Datema, C P; van Eijk, C W E

    2004-07-01

    The neutron backscattering technique may be applied to search for non-metallic landmines in relatively dry soils. A detector system using this technique has been constructed. Tests showed that anti-tank mines can reliably be found, but that, depending on the circumstances, anti-personnel mines may escape detection. A first test with a pulsed neutron generator shows that further improvements can be achieved by applying a window on the neutron transit time.

  19. The status of the Delft University Neutron Backscatter Landmine Detector (DUNBLAD)

    Energy Technology Data Exchange (ETDEWEB)

    Bom, V.R. E-mail: vb@iri.tudelft.nl; Datema, C.P. E-mail: cor.datema@philips.com; Eijk, C.W.E. van E-mail: vaneijk@iri.tudelft.nl

    2004-07-01

    The neutron backscattering technique may be applied to search for non-metallic landmines in relatively dry soils. A detector system using this technique has been constructed. Tests showed that anti-tank mines can reliably be found, but that, depending on the circumstances, anti-personnel mines may escape detection. A first test with a pulsed neutron generator shows that further improvements can be achieved by applying a window on the neutron transit time.

  20. Impact of soil water content on landmine detection using radar and thermal infared sensors

    OpenAIRE

    Hong, S.-H.; Miller, T.W.; H. Tobin; Borchers, B.; Hendrickx, J.M.H.; Lensen, H.A.; Schwering, P.B.W.

    2001-01-01

    Land mines are a major problem in many areas of the world. In spite of the fact that many different types of land mines sensors have been developed, the detection of non-metallic land mines remains very difficult. Most landmine detection sensors are affected by soil properties such as water content, temperature, electrical conductivity and dielectric constant. The most important of these is water content since it directly influences the three other properties. In this study, the ground penetr...

  1. Metalcasting competitiveness research. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Piwonka, T.S.

    1994-08-01

    This report comprises eleven separate reports: prediction of non- metallic particle distribution, electromagnetic separation of inclusions from molten Al alloy, clean steel castings, waste stream identification and treatment, elastic wave lithotripsy for removal of ceramic from investment castings, metal penetration in sand molds, mold-metal interface gas composition, improved Alloy 718, specifications for iron oxide additions to no-bake sands, criteria functions for defect prediction, and computer-aided cooling curve analysis.

  2. Environmental impact of geopressure - geothermal cogeneration facility on wetland resources and socioeconomic characteristics in Louisiana Gulf Coast region. Final report, October 10, 1983-September 31, 1984

    Energy Technology Data Exchange (ETDEWEB)

    Smalley, A.M.; Saleh, F.M.S.; Fontenot, M.

    1984-08-01

    Baseline data relevant to air quality are presented. The following are also included: geology and resource assessment, design well prospects in southwestern Louisiana, water quality monitoring, chemical analysis subsidence, microseismicity, geopressure-geothermal subsidence modeling, models of compaction and subsidence, sampling handling and preparation, brine chemistry, wetland resources, socioeconomic characteristics, impacts on wetlands, salinity, toxic metals, non-metal toxicants, temperature, subsidence, and socioeconomic impacts. (MHR)

  3. Chemical industrial production and applied chemistry of metals and nonmetals in educational program of chemistry in elementary school

    OpenAIRE

    Cvjetićanin Stanko M.; Segedinac Mirjana; Letić Ljubinka B.

    2009-01-01

    In this paper a part of the model of the curriculum, which should improve chemical education in primary schools is presented. The implemented module refers to metals and non-metals in the fields of applied chemistry and chemical industry. Contents of the curriculum from 1974 to 2004 are considered. The quantity and quality of the pupils' knowledge are analyzed. The research showed that the pupils' knowledge is low. The module is implemented for the sake of overcoming the observed drawbacks in...

  4. The Shilu Iron Ore Deposit in Hainan Province, South China: A Structurally and Hydrothermally Reworked and Re-Enriched Lake-Superior-Type BIF Iron Deposit%The Shilu Iron Ore Deposit in Hainan Province,South China: A Structurally and Hydrothermally Reworked and Re-Enriched Lake-Superior-Type BIF Iron Deposit

    Institute of Scientific and Technical Information of China (English)

    XU De-ru; WANG Zhi-lin; XIAO Yong; Bakun-Czubarow Nonna; LIU Zhao-lu; WANG Li; FU Qi-ji; WU Jun; Kusiak Monika Agnieszka

    2009-01-01

    @@ The Shilu iron ore deposit, located in the western Hainan Province, South China, is one of the most important iron-ore mining districts in China not only for its huge reserves of hematite- rich ores, but also for its potentially economic significance of associated metals of copper, cobalt, nickel, silver, lead and zinc, and of non-metals of dolomite, quartzite,barite,gypsum and sulfur.

  5. Environmental and Chemical Aging of Fatty-Acid-Based Vinyl Ester Composites

    Science.gov (United States)

    2011-04-01

    Reactive diluents in vinyl ester and unsaturated polyester resins, such as styrene and methyl methacrylate, are used to reduce the resin viscosity to...Contamination by Fluids [11]) that were selected as a hydrocarbon fuel (JP-8), a solvent ( methyl ethyl ketone [MEK]), and saltwater exposure...Exposure of Non-Metallic Materials. Annu. Book ASTM Stand. 2005. 20 14. MIL-DTL-83133F. Detail Specification: Turbine Fuel, Aviation, Kerosene

  6. A Brief Review of General Patterns of MIC of Carbon Steel and Biodegradation of Concrete

    OpenAIRE

    Javaherdashti, Reza

    2010-01-01

    MIC (Microbiologically influenced corrosion) is an electrochemical type of corrosion enhanced by some types of micro-/ macro-organisms. However, in this paper, MIC will be used to address the corrosion enhanced by micro-organisms. In order for MIC to occur, two minimum requirements are (i) vulnerability of the material and (ii) existence of environmental factors that are favoring MIC. This type of corrosion is known to affect both metals and non-metals. On the other hand, the factors that ren...

  7. Thermodynamics of Organic Compounds

    Science.gov (United States)

    1979-01-01

    General Techniques for Combustion of Liquid/Soli. Organic Compounds by Oxygen Bomb Calorimetry by Arthur J. Head, William D. Good, and Ccrnelius...Mosselman, Chap. 8; Combustion of Liquid/Solid Organic Compounds with Non-Metallic Hetero-Atoms by Arthur J. Head and William D. Good, Chap. 9; in...0 Box 95085 Washington, DC 20234 Los Angeles, CA 90045 National Bureau of Standards CINDAS Chemical Thermodynamics Division Purdue University

  8. MINING IN ECONOMY OF REPUBLIC OF CROATIA

    OpenAIRE

    Željko Matiša

    1996-01-01

    Croatia is not especially rich in mineral ore resources, and therefore it cannot be included into "mining countries". Nevertheless since exploitation of mineral resources is a primary activity in economy of any country, mining in Croatia is given a great significance. In Croatia, research and exploitation of oil and gas is considered to be the most significant. Exploitation of mineral resources for production of metals is negligable, while esploitation of non-metals satisfies the majority ...

  9. Ionic liquids in the synthesis of nanoobjects

    Energy Technology Data Exchange (ETDEWEB)

    Tarasova, Natalia P; Smetannikov, Yurii V; Zanin, A A [Institute of Chemistry and Problems of Sustainable Development D.I.Mendeleev University of Chemical Technology of Russia (Russian Federation)

    2010-08-12

    Data on the usage of the novel green solvents, ionic liquids, in the synthesis of nanoobjects and their stabilization are considered. The information is structured according to the resulting products of the synthetic processes: nanoparticles of noble metals, nanoparticles of non-metals, nanoparticles of metal oxides and chalcogenides, nanocomposites, and highly dispersed polymers. The conclusion is made that the ionic liquids might determine the structure and the properties of the nanoobjects, thus opening new fundamental and technological horizons in nanochemistry.

  10. Ionic liquids in the synthesis of nanoobjects

    Science.gov (United States)

    Tarasova, Natalia P.; Smetannikov, Yurii V.; Zanin, A. A.

    2010-08-01

    Data on the usage of the novel green solvents, ionic liquids, in the synthesis of nanoobjects and their stabilization are considered. The information is structured according to the resulting products of the synthetic processes: nanoparticles of noble metals, nanoparticles of non-metals, nanoparticles of metal oxides and chalcogenides, nanocomposites, and highly dispersed polymers. The conclusion is made that the ionic liquids might determine the structure and the properties of the nanoobjects, thus opening new fundamental and technological horizons in nanochemistry.

  11. Cost Effectiveness of Composite Materials on the F-15 and F-16 Aircrafts

    Science.gov (United States)

    1989-09-01

    reinforcement are REINFORCEMENTS COMPOSITE THE MATRIX AND FILLERS FORMING STRUCTURES AND PROCESSING LAMINATES, FILMS + WHISKERS, FIBERS, . AND FOILS, HONEY ...303, 327, and 353 respectively. For the F-15 honey comb assembly, horizontal stabilator assembly, the data range for flight hours, sorties, and...added to a cementing agent to make concrete. 2. Boron Essentially a non-metal occurring naturally as in borax or boric acid. 3. Carbon An element that

  12. Identification of an operon involved in fluoride resistance in Enterobacter cloacae FRM

    OpenAIRE

    Xiaoqing LIU; Tian, Jian; Liu, Lihui; Zhu, Tao; Yu, Xiaoxia; Chu, Xiaoyu; Yao, Bin; Wu, Ningfeng; Fan, Yunliu

    2017-01-01

    Fluorine is ubiquitous and the most active non-metal element in nature. While many microorganisms have developed fluoride resistance as a result of the widespread and prolonged application of oral hygiene products, the mechanisms used by these organisms to overcome fluoride toxicity are incompletely understood. In this study, a fluoride-resistant strain, Enterobacter cloacae FRM, was identified which could grow well at a fluoride concentration of 4,000?mg/L. According to comparative genomics,...

  13. Strong Exchange Anisotropy in Heavy Atom Radical Ferromagnets

    Science.gov (United States)

    Winter, Stephen

    2012-02-01

    The discovery twenty years ago of ferromagnetic ordering in ``light atom'' p-block (N, O based) radicals appeared to provide a major conceptual advance, suggesting the possibility of a new era in non-metal molecular magnetism. However, the weak through-space magnetic exchange interactions present in these early radical-based ferromagnets afforded very low Curie temperatures TC (JACS 130, 8414-8425 (2008), JACS 133, 8126-8129 (2011).

  14. Non-Catalytic Reforming with Applications to Portable Power

    Science.gov (United States)

    2013-10-01

    and J.J. Beaman, Jr., “Freeform Fabrication of Non-Metallic Objects by Selective Laser Sintering and Infiltration”, Materials Science Forum, 561-565...eventually either blows off or flashes back. This has prompted the design and development of reactors with stationary reaction zones [9, 70]. In contrast...the flame will propagate into the porous flow straighteners and flash back. Figure B.3 shows the stable operating conditions for premixed heptane

  15. Microstructurally sensitive crack nucleation around inclusions in powder metallurgy nickel based superalloys

    OpenAIRE

    Jiang, J; Yang, J; Zhang, T.; J Zou; Wang,Y.,; Dunne, F.P.E.; Britton, T. B.

    2016-01-01

    ? 2016 Acta Materialia Inc.Nickel-based superalloys are used in high strength, high-value applications, such as gas turbine discs in aero engines. In these applications the integrity of the disc is critical and therefore understanding crack initiation mechanisms is of high importance. With an increasing trend towards powder metallurgy routes for discs, sometimes unwanted non-metallic inclusions are introduced during manufacture. These inclusions vary in size from ?10??m to 200??m which is com...

  16. Test Operations Procedure (TOP) 01-1-065 Accelerated Corrosion Durability

    Science.gov (United States)

    2013-10-15

    as a general guide. This procedure is focused on metallic corrosion and does not accelerate Microbial Induced Corrosion (MIC) or degradation of non...metallic materials such as plastics or rubbers due to solar exposure or other causes of degradation besides what is identified in this procedure... concentration salt solutions that are present on roadways, typically from road deicing salts. The application includes exposure to fine mists from elevated

  17. Technological Aspects of Low-Alloyed Cast Steel Massive Casting Manufacturing

    Directory of Open Access Journals (Sweden)

    Szajnara J.

    2013-12-01

    Full Text Available In the paper authors have undertaken the attempt of explaining the causes of cracks net occurrence on a massive 3-ton cast steel casting with complex geometry. Material used for casting manufacturing was the low-alloyed cast steel with increased wear resistance modified with vanadium and titanium. The studies included the primary and secondary crystallization analysis with use of TDA and the qualitative and quantitative analysis of non-metallic inclusions.

  18. Characterization of Particles Created By Laser-Driven Hydrothermal Processing

    Science.gov (United States)

    2016-06-01

    the 30 MW/cm2 and 500 MW/cm2 intensity range using 15-ns, 351-nm laser pulses with an energy range of 1 J to 0.35 J to strike impure, non - metallic ... inclusions and particles rich in several transition elements, most notably iron and titanium. Analysis of liquid media collected after laser processing...The bulk and crushed obsidian and tektite samples contained inclusions and particles rich in several transition elements, most notably iron and

  19. Stabilization of the spark-discharge point on a sample surface by laser irradiation for steel analysis.

    Science.gov (United States)

    Matsuta, Hideyuki; Kitagawa, Kuniyuki; Wagatsuma, Kazuaki

    2006-10-01

    A combined technique with laser irradiation is suggested to control spark discharge for analytical use, having a unique feature that firing points of the spark discharge can be fixed by laser irradiation. Because the spark discharge easily initiates at particular surface sites, such as non-metallic inclusions, called selective discharge, the concentration of some elements sometimes deviates from their average one in spark discharge optical emission spectrometry. Therefore, stabilization of firing points on a sample surface could improve the analytical precision.

  20. Quantitative characterization of mns inclusions in S355 steel regarding to solidification rate

    Directory of Open Access Journals (Sweden)

    Mahmutović Aida

    2013-01-01

    Full Text Available A practice of special interest for metallurgical steelmaking is the relationship between redistribution of solute elements and dendrite microsegregation that occurs during solidification. These phenomena have a significant impact on the final properties of cast and forged products. In this paper, a calculation of the characteristic chemical phases in S355 steel using a software program Thermo-Calc is presented. Also, the paper presents experimental measurements of the dendrites size and non-metallic inclusions using optical and electron probe microanalyzer, as well as the calculation of the local solidification rate on the particular example. These phenomena are of special interest when it comes to thin castings and higher cooling rates. Thin castings require higher quality of casting surface, corresponding distribution, and character than those of non-metallic inclusions. Thermo-calc software was used for calculation of equilibrium phases, temperature ranges of solidification of tested material, and temperature range for developing characteristic equilibrium phase. It was found that during solidification and cooling processes manganese sulphide inclusions were formed. Additionally, accurate values for solidus and liquidus temperatures, which coincide with the values of solidus and liquidus temperatures obtained by the Thermo Calc, were calculated. Using optical and electron probe microanalyzer, the type of inclusions were confirmed, whereas chemical composition and size measurement of dendrites, and formed non-metallic inclusions were determined. Mapping and Linescan methods were used to examine the size and exact chemical composition of sulphides in atomic percents. Using secondary dendrites local solidification rate was calculated (for casting surface area solidification rate was 5 K/s. This paper gives contribution to better understanding the influence of cooling rate on casting microstructure formation and dendrites, which essentially

  1. Experience with ferrosilicoaluminum alloy during deoxidation of steel

    Directory of Open Access Journals (Sweden)

    A. Mekhtiyev

    2015-10-01

    Full Text Available The article describes the process of deoxidation quiet and low-alloyed steel alloy ferrosilicoaluminum complex in comparison the existing, and with steel deoxidation technology with conventional alloys - ferrosilicon and secondary aluminum. A comparative analysis of quality steel, non-metallic inclusions metallographic studies and studies of the mechanical properties of the resulting steel was done. On a large array of experimental steel proved cost-effectiveness and feasibility of ferrosilicoaluminum during deoxidation quiet and low-alloyed steel.

  2. Demonstration/Validation of the Snap Sampler Passive Ground Water Sampling Device

    Science.gov (United States)

    2011-06-01

    direction, although the direction of groundwater movement locally is influenced by water -supply wells and by groundwater extraction and treatment systems...Validation of the Snap Sampler Passive Ground Water Sampling Device June 2011 i COST & PERFORMANCE REPORT Project: ER-200630 TABLE OF CONTENTS...range of analyte types. These included dissolved and total inorganics (including non-metal anions, metalloids , and metals) and four volatile organic

  3. Crack initiation and propagation induced by inclusions in a nickel-base P/M superalloy under fatigue load

    Institute of Scientific and Technical Information of China (English)

    ZENG Yanping; ZHANG Maicang; DONG Jianxin; ZHANG Lina; XIE Xishan

    2005-01-01

    In situ fatigue tests in special designed SEM were conducted to trace the whole process of crack initiation and propagation till to fracture in nickel-base P/M superalloy seeded inclusions. The experimental results show that non-metallic inclusions can induce crack initiation. When the inclusion size is larger than the critical one, the crack can propagate as the main crack that induces the specimen to fracture. As a result, the LCF life of the specimen decreases.

  4. Design, manufacturing and testing of Controllable Rubber Trailing Edge Flaps

    DEFF Research Database (Denmark)

    Løgstrup Andersen, Tom; Aagaard Madsen, Helge; Barlas, Thanasis K

    The overall goal for the INDUFLAP project was realization of a test facility for development and test of Controllable Rubber Trailing Edge Flaps (CRTEF) for wind turbines. This report covers experimental work at DTU Wind Energy including design, manufacture and test of different configurations...... of flaps with voids in chord- or spanwise direction. Development of rubber flaps has involved further design improvements. Non-metallic spring elements and solutions for sealing of continuous extruded rubber profiles have been investigated....

  5. Innovative Navigation Systems to Support Digital Geophysical Mapping

    Science.gov (United States)

    2006-02-17

    Treated No intrusive activities were undertaken nor any material handled. 3.6.4. Residuals Handling This section is not applicable. 3.6.5...The four Cs- vapour sensors were equally separated by 40cm and supported on a non-metallic frame, as shown on the right side of the photograph in Figure...acquisition system showing the four Cs vapour magnetometer sensors at the front of the array (right of photo) and the reflective prism (red cube

  6. Recikliranje gnetnih aluminijevih zlitin iz nizkocenovnih vrst metalurško čistega odpadnega aluminija

    OpenAIRE

    Kevorkijan, Varužan

    2015-01-01

    In the recycling of wrought aluminium alloys from lower grades of scrap (metallurgically clean but highly contaminated with non-metallic impurities) the following two tasks were identified as the most demanding: (i) achieving the required final chemical composition of an alloy with a minimal addition of primary aluminium and alloying elements; and (ii) keeping the level of impurities (inclusions, hydrogen, trace elements and alkali metals) in the molten metal below the critical level. Because...

  7. Advances in atomic spectroscopy

    CERN Document Server

    Sneddon, J

    1995-01-01

    This series describes selected advances in the area of atomic spectroscopy. It is promarily intended for the reader who has a background in atmoic spectroscopy; suitable to the novice and expert. Although a widely used and accepted method for metal and non-metal analysis in a variety of complex samples, Advances in Atomic Spectroscopy covers a wide range of materials. Each Chapter will completely cover an area of atomic spectroscopy where rapid development has occurred.

  8. Ultraviolet (UV)-Curable Coatings for Aerospace Applications

    Science.gov (United States)

    2012-08-31

    unlimited. PA Release #: 88ABW-2014-5955 Aircraft substrates may be made of aluminum, steel, other metallic alloys , or non-metallic composite...Nonmagnetic Coatings Applied to Ferrous Metals and Nonmagnetic, Nonconductive Coatings Applied to Non- Ferrous Metals. Three or more thickness readings, per...Dry Film Thickness of Nonmagnetic Coatings Applied to Ferrous Metals and Nonmagnetic, Nonconductive Coatings Applied to Non- Ferrous Metals All

  9. Comparative Strategy: An International Journal. Volume 13. Number 1. January-March 1994

    Science.gov (United States)

    1994-03-01

    of economy. Production of combat aircraft in the USSR has actually created a variety of branches of industry, such as non- ferrous light- alloy ...by the East to overcome its economic lag through certain military " trumps ." In this context, it seems to me that the litmus test of the partnership...materials and Russia Military and Technical Policy 75 alloys with enhanced mechanical properties, including non-metallic composites, are also coming

  10. A Summary of the Naval Postgraduate School Research Programs and Recent Publications.

    Science.gov (United States)

    1991-09-01

    the U.S. Navy has been replacing the HY80 -100 series of high strength Fox, A.G., Mattes, V.R., Mikalac, S. and Vassilaros, alloy steels with their high...Crystallographic and Chemical 161 Characterization of Microstructures and Non-Metallic Inclusions in High- Strength, Low-Alloy (HSLA) Steels and their...with acoustic emission (AE) in the detection of matrix cracking in graphite-epoxy materials and debonding in adhesives. He is also assessing the

  11. Selective etching of silicon carbide films

    Science.gov (United States)

    Gao, Di; Howe, Roger T.; Maboudian, Roya

    2006-12-19

    A method of etching silicon carbide using a nonmetallic mask layer. The method includes providing a silicon carbide substrate; forming a non-metallic mask layer by applying a layer of material on the substrate; patterning the mask layer to expose underlying areas of the substrate; and etching the underlying areas of the substrate with a plasma at a first rate, while etching the mask layer at a rate lower than the first rate.

  12. Determinants of Electricity Demand in Nonmetallic Mineral Products Industry: Evidence from a Comparative Study of Japan and China

    Directory of Open Access Journals (Sweden)

    Gang Du

    2015-06-01

    Full Text Available Electricity intensity is an important indicator for measuring production efficiency. A comparative study could offer a new perspective on investigating determinants of electricity demand. The Japanese non-metallic mineral products industry is chosen as the object for comparison considering its representative position in production efficiency. By adopting the cointegration model, this paper examines influencing factors of electricity demand in Japanese and Chinese non-metallic mineral products industries under the same framework. Results indicate that although economic growth and industrial development stages are different between the two countries, major factors that affect the sectoral energy consumption are the same. Specifically, economic growth and industrial activity contribute to the growth of sectoral electricity consumption, while R&D intensity, per capita productivity and electricity price are contributors to the decline of sectoral electricity consumption. Finally, in order to further investigate the development trend of sectoral electricity demand, future electricity consumption and conservation potential are predicted under different scenarios. Electricity demand of the Chinese non-metallic mineral products industry is predicted to be 680.53 TWh (terawatt-hours in 2020 and the sectoral electricity conservation potentials are estimated to be 118.26 TWh and 216.25 TWh under the moderate and advanced electricity-saving scenarios, respectively.

  13. NanoPCR observation: different levels of DNA replication fidelity in nanoparticle-enhanced polymerase chain reactions

    Science.gov (United States)

    Shen, Cenchao; Yang, Wenjuan; Ji, Qiaoli; Maki, Hisaji; Dong, Anjie; Zhang, Zhizhou

    2009-11-01

    Nanoparticle-assisted PCR (polymerase chain reaction) technology is getting more and more attention recently. It is believed that some of the DNA recombinant technologies will be upgraded by nanotechnology in the near future, among which DNA replication is one of the core manipulation techniques. So whether or not the DNA replication fidelity is compromised in nanoparticle-assisted PCR is a question. In this study, a total of 16 different metallic and non-metallic nanoparticles (NPs) were tested for their effects on DNA replication fidelity in vitro and in vivo. Sixteen types of nanomaterials were distinctly different in enhancing the PCR efficiency, and their relative capacity to retain DNA replication fidelity was largely different from each other based on rpsL gene mutation assay. Generally speaking, metallic nanoparticles induced larger error rates in DNA replication fidelity than non-metallic nanoparticles, and non-metallic nanomaterials such as carbon nanopowder or nanotubes were still safe as PCR enhancers because they did not compromise the DNA replication fidelity in the Taq DNA polymerase-based PCR system.

  14. Use of large pieces of printed circuit boards for bioleaching to avoid 'precipitate contamination problem' and to simplify overall metal recovery.

    Science.gov (United States)

    Adhapure, N N; Dhakephalkar, P K; Dhakephalkar, A P; Tembhurkar, V R; Rajgure, A V; Deshmukh, A M

    2014-01-01

    Very recently bioleaching has been used for removing metals from electronic waste. Most of the research has been targeted to using pulverized PCBs for bioleaching where precipitate formed during bioleaching contaminates the pulverized PCB sample and making the overall metal recovery process more complicated. In addition to that, such mixing of pulverized sample with precipitate also creates problems for the final separation of non metallic fraction of PCB sample. In the present investigation we attempted the use of large pieces of printed circuit boards instead of pulverized sample for removal of metals. Use of large pieces of PCBs for bioleaching was restricted due to the chemical coating present on PCBs, the problem has been solved by chemical treatment of PCBs prior to bioleaching. In short,•Large pieces of PCB can be used for bioleaching instead of pulverized PCB sample.•Metallic portion on PCBs can be made accessible to bacteria with prior chemical treatment of PCBs.•Complete metal removal obtained on PCB pieces of size 4 cm × 2.5 cm with the exception of solder traces. The final metal free PCBs (non metallic) can be easily recycled and in this way the overall recycling process (metallic and non metallic part) of PCBs becomes simple.

  15. Microbially-mediated method for synthesis of non-oxide semiconductor nanoparticles

    Science.gov (United States)

    Phelps, Tommy J.; Lauf, Robert J.; Moon, Ji Won; Rondinone, Adam J.; Love, Lonnie J.; Duty, Chad Edward; Madden, Andrew Stephen; Li, Yiliang; Ivanov, Ilia N.; Rawn, Claudia Jeanette

    2014-06-24

    The invention is directed to a method for producing non-oxide semiconductor nanoparticles, the method comprising: (a) subjecting a combination of reaction components to conditions conducive to microbially-mediated formation of non-oxide semiconductor nanoparticles, wherein said combination of reaction components comprises i) anaerobic microbes, ii) a culture medium suitable for sustaining said anaerobic microbes, iii) a metal component comprising at least one type of metal ion, iv) a non-metal component containing at least one non-metal selected from the group consisting of S, Se, Te, and As, and v) one or more electron donors that provide donatable electrons to said anaerobic microbes during consumption of the electron donor by said anaerobic microbes; and (b) isolating said non-oxide semiconductor nanoparticles, which contain at least one of said metal ions and at least one of said non-metals. The invention is also directed to non-oxide semiconductor nanoparticle compositions produced as above and having distinctive properties.

  16. Microbially-mediated method for synthesis of non-oxide semiconductor nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Phelps, Tommy J.; Lauf, Robert J.; Moon, Ji-Won; Rondinone, Adam Justin; Love, Lonnie J.; Duty, Chad Edward; Madden, Andrew Stephen; Li, Yiliang; Ivanov, Ilia N.; Rawn, Claudia Jeanette

    2017-09-19

    The invention is directed to a method for producing non-oxide semiconductor nanoparticles, the method comprising: (a) subjecting a combination of reaction components to conditions conducive to microbially-mediated formation of non-oxide semiconductor nanoparticles, wherein said combination of reaction components comprises i) anaerobic microbes, ii) a culture medium suitable for sustaining said anaerobic microbes, iii) a metal component comprising at least one type of metal ion, iv) a non-metal component comprising at least one non-metal selected from the group consisting of S, Se, Te, and As, and v) one or more electron donors that provide donatable electrons to said anaerobic microbes during consumption of the electron donor by said anaerobic microbes; and (b) isolating said non-oxide semiconductor nanoparticles, which contain at least one of said metal ions and at least one of said non-metals. The invention is also directed to non-oxide semiconductor nanoparticle compositions produced as above and having distinctive properties.

  17. Study of Random Wire Type Regenerators for Stirling Cryocoolers

    Science.gov (United States)

    Jeong, Sangkwon; Nam, Kwanwoo; Choi, Sungryel

    2004-06-01

    This paper describes the performance evaluation for the random wire type regenerator used in Stirling cryocoolers. Metallic and non-metallic regenerators are tested and analyzed. Non-metallic regenerator we test is made of high-temperature resistant polymer. First, the ineffectiveness is determined by measuring the instantaneous pressure, the flow rate and the gas temperature at both ends of the regenerator. The cold-end temperature is maintained around 100 K and the operating frequency is fixed at 60 Hz. It is found that the non-metallic regenerator with high heat transfer area has a low ineffectiveness even though its volumetric heat capacity is lower than the metallic regenerator. Second, dynamic analysis is performed for the displacer of Stirling cryocooler containing the above regenerators. Oscillating flow model is proposed to accurately predict the pressure drop through the regenerator. Amplitude and phase angle of the displacer are calculated both from the oscillating flow model and the steady flow model. Superiority of the proposed oscillating flow model is demonstrated by the comparison between the analysis result and the experimental measurements.

  18. Intelligent Sensor for Non-destructive Tests Applications

    Directory of Open Access Journals (Sweden)

    Irinela CHILIBON

    2011-02-01

    Full Text Available This paper presents theoretical and experimental research concerning the manufacture of an intelligent piezoceramic sensor for non-destructive tests (NDT applications in non-metallic materials. The impact-echo method is suitable for determination of flaw in the material structure, based on stress wave propagation. This method could be applied for non-metallic materials with rugged and non-homogeneous structures. The active element of the intelligent piezoceramic sensor for NDT applications is a piezoceramic disc which converts the vibrations into electrical signal, amplified by an amplifier electronic circuit. The radial resonant frequency of the piezoceramic disc is 40.5 kHz, optimum for the ultrasound and low frequency sound vibration propagation into non-metallic materials. The intelligent sensor with piezoceramic disc is composed by: PZT piezoceramic disc, mechanical elements, acoustic attenuation element and amplifier electronic circuit, all together fixed into a cylindrical aluminium case. The advantage of this sensor is the possibility to be controlled by microcontroller.

  19. Use of large pieces of printed circuit boards for bioleaching to avoid ‘precipitate contamination problem’ and to simplify overall metal recovery

    Science.gov (United States)

    Adhapure, N.N.; Dhakephalkar, P.K.; Dhakephalkar, A.P.; Tembhurkar, V.R.; Rajgure, A.V.; Deshmukh, A.M.

    2014-01-01

    Very recently bioleaching has been used for removing metals from electronic waste. Most of the research has been targeted to using pulverized PCBs for bioleaching where precipitate formed during bioleaching contaminates the pulverized PCB sample and making the overall metal recovery process more complicated. In addition to that, such mixing of pulverized sample with precipitate also creates problems for the final separation of non metallic fraction of PCB sample. In the present investigation we attempted the use of large pieces of printed circuit boards instead of pulverized sample for removal of metals. Use of large pieces of PCBs for bioleaching was restricted due to the chemical coating present on PCBs, the problem has been solved by chemical treatment of PCBs prior to bioleaching. In short,•Large pieces of PCB can be used for bioleaching instead of pulverized PCB sample.•Metallic portion on PCBs can be made accessible to bacteria with prior chemical treatment of PCBs.•Complete metal removal obtained on PCB pieces of size 4 cm × 2.5 cm with the exception of solder traces. The final metal free PCBs (non metallic) can be easily recycled and in this way the overall recycling process (metallic and non metallic part) of PCBs becomes simple. PMID:26150951

  20. Thermal stress in a bi-material assembly with a 'piecewise-continuous' bonding layer: theorem of three axial forces

    Science.gov (United States)

    Suhir, E.

    2009-02-01

    We consider a bi-material assembly with a 'piecewise-continuous' bonding layer. The layer is characterized by different elastic constants of its 'pieces' (segments) and is assumed to be thin. Young's moduli of all the 'pieces' of the bonding layer are significantly lower than the moduli of the adherend materials. In such a situation the coefficient of thermal expansion (CTE) of the bonding material need not be accounted for. Only the interfacial compliance of the bonding layer is important. This is indeed the case for the majority of electronic, opto-electronic or photonic assemblies. We consider the situation when the assembly is manufactured at an elevated temperature and is subsequently cooled down to a low (say, room) temperature. The objective of the analysis is to develop a simple, easy-to-use and physically meaningful analytical ('mathematical') predictive model for the evaluation of the interfacial shearing stresses that arise at the boundaries of the 'pieces' (segments) of the bonding layer and at the assembly edge. The basic equation is obtained for the thermally induced forces acting in the adherends' cross-sections that correspond to the boundaries between the dissimilar portions of the bonding layer. This equation has the form of the theorem of three (bending) moments in the theory of multi-span beams lying on separate simple supports and could therefore be called the 'theorem of three axial forces'. We show, as an illustration, how this equation could be employed to design a bi-material assembly with an inhomogeneous bonding layer and with low interfacial shearing stresses. Low shearing stresses will certainly result in lower peeling stresses as well. The numerical example is carried out for an assembly with a relatively high-modulus bonding material in its mid-portion (aimed primarily at providing good adhesion and, if necessary, good heat transfer as well) and a low-modulus material in its peripheral portions (aimed primarily at bringing down the

  1. Integrity of disposable nitrile exam gloves exposed to simulated movement.

    Science.gov (United States)

    Phalen, Robert N; Wong, Weng Kee

    2011-05-01

    Every year, millions of health care, first responder, and industry workers are exposed to chemical and biological hazards. Disposable nitrile gloves are a common choice as both a chemical and physical barrier to these hazards, especially as an alternative to natural latex gloves. However, glove selection is complicated by the availability of several types or formulations of nitrile gloves, such as low-modulus, medical grade, low filler, and cleanroom products. This study evaluated the influence of simulated movement on the physical integrity (i.e., holes) of different nitrile exam glove brands and types. Thirty glove products were evaluated out-of-box and after exposure to simulated whole-glove movement for 2 hr. In lieu of the traditional 1 L water-leak test, a modified water-leak test, standardized to detect a 0.15 ± 0.05 mm hole in different regions of the glove, was developed. A specialized air inflation method simulated bidirectional stretching and whole-glove movement. A worst-case scenario with maximum stretching was evaluated. On average, movement did not have a significant effect on glove integrity (chi-square; p=0.068). The average effect was less than 1% between no movement (1.5%) and movement (2.1%) exposures. However, there was significant variability in glove integrity between different glove types (p≤0.05). Cleanroom gloves, on average, had the highest percentage of leaks, and 50% failed the water-leak test. Low-modulus and medical grade gloves had the lowest percentages of leaks, and no products failed the water-leak test. Variability in polymer formulation was suspected to account for the observed discrepancies, as well as the inability of the traditional 1 L water-leak test to detect holes in finger/thumb regions. Unexpectedly, greater than 80% of the glove defects were observed in the finger and thumb regions. It is recommended that existing water-leak tests be re-evaluated and standardized to account for product variability.

  2. Fast Horizontal Contraction without Vertical Strain: Puzzling Interseismic Geodetic Measurements in the Ventura Basin, CA

    Science.gov (United States)

    Marshall, S. T.; Phillips, J. R., III; Funning, G.; Owen, S. E.

    2014-12-01

    Ongoing contraction related to the regional-scale left step in the San Andreas fault, (i.e. the Big Bend) has resulted in a complex network of oblique-reverse slip faults that now accommodate shortening across the Ventura basin. Continuous GPS sites from the Plate Boundary Observatory measure horizontal contraction rates across the Ventura basin of approximately 7 mm/yr oriented north-northwest with rates decreasing to the west and east. Inversion of horizontal GPS velocities highlights a zone of localized fast horizontal contraction rates that roughly follow the Ventura basin where seismic velocity models show low modulus sediments. This pattern of localized horizontal contraction can be explained with simple models creeping reverse faults (edge dislocations) at depth; however, such models predict significant uplift gradients that are not observed in the GPS or InSAR data. In fact, the GPS and InSAR show almost no vertical strains in the regions that exhibit fast horizontal strains. Thus, the outstanding unanswered question in the region is: how can interseismic deformation in a contractional setting produce localized horizontal contraction with little to no uplift gradients? To assess whether the simple models are inadequate in their fault geometry, we use a complex interseismic mechanical model incorporating three-dimensional, nonplanar, and geologically constrained fault surfaces from the Southern California Earthquake Center's Community Fault Model (CFM). This model produces very little vertical strains, but cannot match the magnitudes and localization of fast horizontal strains, likely due to the modeled homogeneous rock stiffness. In the end, we suggest that it is possible that a significant portion of the horizontal strains are due to strain localization in the low modulus sediments of the Ventura basin, which may not be released in a future earthquake and potentially mask the interseismic deformation due to faulting. Additionally, the CFM-based model

  3. Toward Molecular Engineering of Polymer Glasses

    Energy Technology Data Exchange (ETDEWEB)

    Freed, Karl F [Univ. of Chicago, IL (United States); Xu, Wen-Sheng [Univ. of Chicago, IL (United States); Dudowicz, Jacek B [Univ. of Chicago, IL (United States); Douglas, Jack F [National Inst. of Standards and Technology (NIST), Boulder, CO (United States)

    2017-04-05

    to test the theory by directly comparing between the predictions of our generalized entropy theory with experiment and with simulations and to expand the vistas of the theory to describe a wider range of important systems (e.g. glass formation in binary blends and systems with specific interactions) and phenomena that are describable by the generalized entropy theory. In addition, we have addressed longstanding fundamental problems associated with the validity of the Adam-Gibbs theory, one of the underpinnings of the general entropy theory. Theoretical advances to enable describing the properties of glass-formation over a wider class of important polymeric systems, included semi-flexible systems, the more general situation of specific interactions, and more. Our recent work removes the simplest approximation uses the simplest model in which the interaction is approximated by a single, monomer average. Thus, the theory has been extended to allow some variations of the energy parameters between the atoms within the monomers. The theory has also been extended to include all the contributions from chain semi-flexibility. Both projects are extremely difficult, but the payback is that the process of solving the problems developed strong theoretical skills in Dr. Xu, who has recently begun a postdoc position at ORNL. The theory has also been extended to describe glass formation in partially miscible blends, with good general agreement with experiment. Again, the development of the theory presented an extremely difficult problem, but the payback is the development of a theory for a very important class of systems. Another project provides an extremely simple approximation for certain properties of glass formation in polymer melts and should make the theory more accessible to everyone.

  4. k-space image correlation to probe the intracellular dynamics of gold nanoparticles

    Science.gov (United States)

    Bouzin, M.; Sironi, L.; Chirico, G.; D'Alfonso, L.; Inverso, D.; Pallavicini, P.; Collini, M.

    2016-04-01

    The collective action of dynein, kinesin and myosin molecular motors is responsible for the intracellular active transport of cargoes, vesicles and organelles along the semi-flexible oriented filaments of the cytoskeleton. The overall mobility of the cargoes upon binding and unbinding to motor proteins can be modeled as an intermittency between Brownian diffusion in the cell cytoplasm and active ballistic excursions along actin filaments or microtubules. Such an intermittent intracellular active transport, exhibited by star-shaped gold nanoparticles (GNSs, Gold Nanostars) upon internalization in HeLa cancer cells, is investigated here by combining live-cell time-lapse confocal reflectance microscopy and the spatio-temporal correlation, in the reciprocal Fourier space, of the acquired image sequences. At first, the analytical theoretical framework for the investigation of a two-state intermittent dynamics is presented for Fourier-space Image Correlation Spectroscopy (kICS). Then simulated kICS correlation functions are employed to evaluate the influence of, and sensitivity to, all the kinetic and dynamic parameters the model involves (the transition rates between the diffusive and the active transport states, the diffusion coefficient and drift velocity of the imaged particles). The optimal procedure for the analysis of the experimental data is outlined and finally exploited to derive whole-cell maps for the parameters underlying the GNSs super-diffusive dynamics. Applied here to the GNSs subcellular trafficking, the proposed kICS analysis can be adopted for the characterization of the intracellular (super-) diffusive dynamics of any fluorescent or scattering biological macromolecule.

  5. Viscoelastic Properties of Hyaluronan in Physiological Conditions [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Mary K. Cowman

    2015-08-01

    Full Text Available Hyaluronan (HA is a high molecular weight glycosaminoglycan of the extracellular matrix (ECM, which is particularly abundant in soft connective tissues. Solutions of HA can be highly viscous with non-Newtonian flow properties. These properties affect the movement of HA-containing fluid layers within and underlying the deep fascia. Changes in the concentration, molecular weight, or even covalent modification of HA in inflammatory conditions, as well as changes in binding interactions with other macromolecules, can have dramatic effects on the sliding movement of fascia. The high molecular weight and the semi-flexible chain of HA are key factors leading to the high viscosity of dilute solutions, and real HA solutions show additional nonideality and greatly increased viscosity due to mutual macromolecular crowding. The shear rate dependence of the viscosity, and the viscoelasticity of HA solutions, depend on the relaxation time of the molecule, which in turn depends on the HA concentration and molecular weight. Temperature can also have an effect on these properties. High viscosity can additionally affect the lubricating function of HA solutions. Immobility can increase the concentration of HA, increase the viscosity, and reduce lubrication and gliding of the layers of connective tissue and muscle. Over time, these changes can alter both muscle structure and function. Inflammation can further increase the viscosity of HA-containing fluids if the HA is modified via covalent attachment of heavy chains derived from Inter-α-Inhibitor. Hyaluronidase hydrolyzes HA, thus reducing its molecular weight, lowering the viscosity of the extracellular matrix fluid and making outflow easier. It can also disrupt any aggregates or gel-like structures that result from HA being modified. Hyaluronidase is used medically primarily as a dispersion agent, but may also be useful in conditions where altered viscosity of the fascia is desired, such as in the treatment of

  6. Layered Thermal Insulation Systems for Industrial and Commercial Applications

    Science.gov (United States)

    Fesmire, James E.

    2015-01-01

    From the high performance arena of cryogenic equipment, several different layered thermal insulation systems have been developed for industrial and commercial applications. In addition to the proven areas in cold-work applications for piping and tanks, the new Layered Composite Insulation for Extreme Environments (LCX) has potential for broader industrial use as well as for commercial applications. The LCX technology provides a unique combination of thermal, mechanical, and weathering performance capability that is both cost-effective and enabling. Industry applications may include, for example, liquid nitrogen (LN2) systems for food processing, liquefied natural gas (LNG) systems for transportation or power, and chilled water cooling facilities. Example commercial applications may include commercial residential building construction, hot water piping, HVAC systems, refrigerated trucks, cold chain shipping containers, and a various consumer products. The LCX system is highly tailorable to the end-use application and can be pre-fabricated or field assembled as needed. Product forms of LCX include rigid sheets, semi-flexible sheets, cylindrical clam-shells, removable covers, or flexible strips for wrapping. With increasing system control and reliability requirements as well as demands for higher energy efficiencies, thermal insulation in harsh environments is a growing challenge. The LCX technology grew out of solving problems in the insulation of mechanically complex cryogenic systems that must operate in outdoor, humid conditions. Insulation for cold work includes equipment for everything from liquid helium to chilled water. And in the middle are systems for LNG, LN2, liquid oxygen (LO2), liquid hydrogen (LH2) that must operate in the ambient environment. Different LCX systems have been demonstrated for sub-ambient conditions but are capable of moderately high temperature applications as well.

  7. Self-attracting polymers in two dimensions with three low-temperature phases

    Science.gov (United States)

    Bedini, A.; Owczarek, A. L.; Prellberg, T.

    2017-03-01

    We study via Monte Carlo simulation a generalisation of the so-called vertex interacting self-avoiding walk (VISAW) model on the square lattice. The configurations are actually not self-avoiding walks but rather restricted self-avoiding trails (bond avoiding paths) which may visit a site of the lattice twice provided the path does not cross itself: to distinguish this subset of trails we shall call these configurations grooves. Three distinct interactions are added to the configurations: firstly the VISAW interaction, which is associated with doubly visited sites, secondly a nearest neighbour interaction in the same fashion as the canonical interacting self-avoiding walk (ISAW) and thirdly, a stiffness energy to enhance or decrease the probability of bends in the configuration. In addition to the normal high temperature phase we find three low temperature phases: (i) the usual amorphous liquid drop-like ‘globular’ phase, (ii) an anisotropic ‘β-sheet’ phase with dominant configurations consisting of aligned long straight segments, which has been found in semi-flexible nearest neighbour ISAW models, and (iii) a maximally dense phase, where the all sites of the path are associated with doubly visited sites (except those of the boundary of the configuration), previously observed in interacting self-avoiding trails. We construct a phase diagram using the fluctuations of the energy parameters and three order parameters. The β-sheet and maximally dense phases do not seem to meet in the phase space and are always separated by either the extended or globular phases. We focus attention on the transition between the extended and maximally dense phases, as that is the transition in the original VISAW model. We find that for the path lengths considered there is a range of parameters where the transition is first order and it is otherwise continuous.

  8. Which axial and bending stiffnesses of posterior implants are required to design a flexible lumbar stabilization system?

    Science.gov (United States)

    Schmidt, Hendrik; Heuer, Frank; Wilke, Hans-Joachim

    2009-01-01

    Dynamic stabilization devices have been introduced to clinics as an alternative to rigid fixation. The stiffness of these devices varies widely, whereas the optimal stiffness, achieving a predefined stabilization of the spine, is unknown. This study was focused on the determination of stiffness values for posterior stabilization devices achieving a flexible, semi-flexible or rigid connection between two vertebrae. An extensively validated finite element model of a lumbar spinal segment L4-5 with an implanted posterior fixation device was used in this study. The model was exposed to pure moments of 7.5 and 20Nm around the three principal anatomical directions, simulating flexion, extension, lateral bending and axial rotation. In parametrical studies, the influence of the axial and bending fixator stiffness on the spinal range of motion was investigated. In order to examine the validity of the computed results, an in-vitro study was carried out. In this, the influence of two posterior stabilization devices (DSS and rigidly internal fixator) on the segmental stabilization was investigated. The finite element (FE)-model predicted that each load direction caused a pairing of stiffness relations between axial and bending stiffness. In flexion and extension, however, the bending stiffness had a neglectable effect on the segmental stabilization, compared to the axial stiffness. In contrast, lateral bending and axial rotation were influenced by both stiffness parameters. Except in axial rotation, the model predictions were in a good agreement with the determined in-vitro data. In axial rotation, the FE-model predicted a stiffer segmental behavior than it was determined in the in-vitro study. It is usually expected that high stiffness values are required for a posterior stabilization device to stiffen a spinal segment. We found that already small stiffness values were sufficient to cause a stiffening. Using these data, it may possible to develop implants for certain clinical

  9. Attractive interactions among intermediate filaments determine network mechanics in vitro.

    Directory of Open Access Journals (Sweden)

    Paul Pawelzyk

    Full Text Available Mechanical and structural properties of K8/K18 and vimentin intermediate filament (IF networks have been investigated using bulk mechanical rheometry and optical microrheology including diffusing wave spectroscopy and multiple particle tracking. A high elastic modulus G0 at low protein concentration c, a weak concentration dependency of G0 (G0 ∼ c(0.5 ± 0.1 and pronounced strain stiffening are found for these systems even without external crossbridgers. Strong attractive interactions among filaments are required to maintain these characteristic mechanical features, which have also been reported for various other IF networks. Filament assembly, the persistence length of the filaments and the network mesh size remain essentially unaffected when a nonionic surfactant is added, but strain stiffening is completely suppressed, G0 drops by orders of magnitude and exhibits a scaling G0 ∼ c(1.9 ± 0.2 in agreement with microrheological measurements and as expected for entangled networks of semi-flexible polymers. Tailless K8Δ/K18ΔT and various other tailless filament networks do not exhibit strain stiffening, but still show high G0 values. Therefore, two binding sites are proposed to exist in IF networks. A weaker one mediated by hydrophobic amino acid clusters in the central rod prevents stretched filaments between adjacent cross-links from thermal equilibration and thus provides the high G0 values. Another strong one facilitating strain stiffening is located in the tail domain with its high fraction of hydrophobic amino acid sequences. Strain stiffening is less pronounced for vimentin than for K8/K18 due to electrostatic repulsion forces partly compensating the strong attraction at filament contact points.

  10. Septoglomus fuscum and S. furcatum, two new species of arbuscular mycorrhizal fungi (Glomeromycota).

    Science.gov (United States)

    Blaszkowski, Janusz; Chwat, Gerard; Kovács, Gábor M; Gáspár, Bence K; Ryszka, Przemyslaw; Orlowska, Elzbieta; Pagano, Marcela C; Araújo, Francisca S; Wubet, Tesfaye; Buscot, François

    2013-01-01

    Two new arbuscular mycorrhizal fungal species, (Glomeromycota) Septoglomus fuscum and S. furcatum, are described and illustrated. Spores of S. fuscum usually occur in loose hypogeous clusters, rarely singly in soil or inside roots, and S. furcatum forms only single spores in soil. Spores of S. fuscum are brownish orange to dark brown, globose to subglobose, (20-)47(-90) μm diam, rarely ovoid, 21-50 × 23-60 μm. Their spore wall consists of a semi-persistent, semi-flexible, orange white to golden yellow, rarely hyaline, outer layer, easily separating from a laminate, smooth, brownish orange to dark brown inner layer. Spores of S. furcatum are reddish brown to dark brown, globose to subglobose, (106-) 138(-167) μm diam, rarely ovoid, 108-127 × 135-160 μm, usually with one subtending hypha that is frequently branched below the spore base, or occasionally with two subtending hyphae located close together. Spore walls consists of a semipermanent, hyaline to light orange outermost layer, a semipermanent, hyaline to golden yellow middle layer, and a laminate, smooth, reddish brown to dark brown innermost layer. None of the spore-wall layers of S. fuscum and S. furcatum stain in Melzer's reagent. In the field, S. fuscum was associated with roots of Arctotheca populifolia colonizing maritime dunes located near Strand in South Africa and S. furcatum was associated with Cordia oncocalyx growing in a dry forest in the Ceará State, Brazil. In single-species cultures with Plantago lanceolata as host plant, S. fuscum and S. furcatum formed arbuscular mycorrhizae. Phylogenetic analyses of the SSU, ITS and LSU nrDNA sequences placed the two new species in genus Septoglomus and both new taxa were separated from described Septoglomus species.

  11. Elasticity and inelasticity of silicon nitride/boron nitride fibrous monoliths.

    Energy Technology Data Exchange (ETDEWEB)

    Smirnov, B. I.; Burenkov, Yu. A.; Kardashev, B. K.; Singh, D.; Goretta, K. C.; de Arellano-Lopez, A. R.; Energy Technology; Russian Academy of Sciences; Univer. de Sevilla

    2001-01-01

    A study is reported on the effect of temperature and elastic vibration amplitude on Young's modulus E and internal friction in Si{sub 3}N{sub 4} and BN ceramic samples and Si{sub 3}N{sub 4}/BN monoliths obtained by hot pressing of BN-coated Si{sub 3}N{sub 4} fibers. The fibers were arranged along, across, or both along and across the specimen axis. The E measurements were carried out under thermal cycling within the 20-600 C range. It was found that high-modulus silicon-nitride specimens possess a high thermal stability; the E(T) dependences obtained under heating and cooling coincide well with one another. The low-modulus BN ceramic exhibits a considerable hysteresis, thus indicating evolution of the defect structure under the action of thermoelastic (internal) stresses. Monoliths demonstrate a qualitatively similar behavior (with hysteresis). This behavior of the elastic modulus is possible under microplastic deformation initiated by internal stresses. The presence of microplastic shear in all the materials studied is supported by the character of the amplitude dependences of internal friction and the Young's modulus. The experimental data obtained are discussed in terms of a model in which the temperature dependences of the elastic modulus and their features are accounted for by both microplastic deformation and nonlinear lattice-atom vibrations, which depend on internal stresses.

  12. Investigating the performance and properties of dielectric elastomer actuators as a potential means to actuate origami structures

    Science.gov (United States)

    Ahmed, S.; Ounaies, Z.; Frecker, M.

    2014-09-01

    Origami engineering aims to combine origami principles with advanced materials to yield active origami shapes, which fold and unfold in response to external stimuli. This paper explores the potential and limitations of dielectric elastomers (DEs) as the enabling material in active origami engineering. DEs are compliant materials in which the coupled electro-mechanical actuation takes advantage of their low modulus and high breakdown strength. Until recently, prestraining of relatively thick DE materials was necessary in order to achieve the high electric fields needed to trigger electrostatic actuation without inducing a dielectric breakdown. Although prestrain improves the breakdown strength of the DE films and reduces the voltage required for actuation, the need for a solid frame to retain the prestrain state is a limitation for the practical implementation of DEs, especially for active origami structures. However, the recent availability of thinner DE materials (50 μm, 130 μm, 260 μm) has made DEs a likely medium for active origami. In this work, the folding and unfolding of DE multilayered structures, along with the realization of origami-inspired 3D shapes, are explored. In addition, an exhaustive study on the fundamentals of DE actuation is done by directly investigating the thickness actuation mechanism and comparing their performance using different electrode types. Finally, changes in dielectric permittivity as a function of strain, electrode type and applied electric field are assessed and analyzed. These fundamental studies are key to obtaining more dramatic folding and to realizing active origami structures using DE materials.

  13. Reaction hot-pressing and property-composition relationships of modified sialon - boron nitride hetero-modulus ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Y; Shabalin, I L [Materials and Physics Research Centre, University of Salford, Salford, Greater Manchester, M5 4WT (United Kingdom); Zhang, L [Department of Ceramic and Glass Engineering, CICECO, University of Aveiro, Aveiro 3810-193 (Portugal); Zhdanov, V B, E-mail: i.shabalin@salford.ac.uk [Department of Less-Common Metals, Ural State Technical University, Yekaterinburg 620002 (Russian Federation)

    2011-10-29

    Hetero-modulus ceramics (HMC) present the combination of a ceramic matrix with inclusions of a dispersed phase with considerably lower values of Young's modulus, resulting in a material with significantly advanced properties. Densified '-Si{sub 6-x}Al{sub x}O{sub x}N{sub 8-x} based HMC materials, with various volume contents of low-modulus {alpha}-BN phase and modifiers such as TiN or ZrO{sub 2} in sialon matrix, were prepared by high-temperature reaction hot-pressing in nitrogen atmosphere. The pristine blend composition for reaction hot-pressing consisted of mixed fine powders of Si, Al, B, Ti nitrides and Al, Zr oxides. Statistical design of 2{sup 5-2} fractional factorial and third-order simplex-grid types was used for the experimental studies to estimate the effects of some technological factors on the densification of hot-pressed products and the property-composition relationships of modified HMC materials.

  14. Microhardness of Bone Tissue After Different Alloy Implantation

    Directory of Open Access Journals (Sweden)

    Nataliia Zaitseva

    2015-09-01

    Full Text Available Integral indicator of bone quality is microhardness, which depends both on the condition of the inorganic component and the quality of the extracellular organic matrix. There are a lot of researches indicated microhardness changes around the metal implants, but it is not clear how it change distant from injured place. The aim of our research was to determine the microhardness of the femoral bone at different terms after the implantation of metal alloys with different composition. 65 rabbits were random in 5 groups – intact, control (bone defect and 3 experimental. We used TiVT6 alloy with high elasticity module and β- (Ti-Zr alloy with low Young module for the experimental groups. All alloys were implanted in distal epiphysis of femur. Bone microhardness was detected in periimplanted zone as well as in middle of diaphysis and proximal epiphysis. Injury of bone leads to a decrease in the hardness in the zone of the defec as well as in distal zones, followed by recovery up to 6 month. Use the classic high-modulus alloy TiVT6 leads to a significant decrease in the microhardness of all sections of bone in the early and late postoperative period. Implantation of low modulus alloy β (Ti-Zr leads to a reduction of hardness just after 1 and 3 months after the injury, and the use of hydroxyapatite coating significantly reduces the loss of bone quality at all times after implantation.

  15. Characterisation of some experimental silicones.

    Science.gov (United States)

    Parker, S; Meththananda, I; Braden, M; Pearson, G J

    2006-12-01

    Release of antimicrobials/antibacterials like chlorhexidine diacetate (CHD) has proved successful in inhibiting Candidal colonisation of silicone-based biomaterials. However, their addition will increase water uptake and may compromise the mechanical integrity. Two experimental silicones (S1 and S2) differing only in the surface treatment of the filler, were investigated. Ultimate tensile strength (UTS), % elongation at break (Eb), Shore A hardness and, when doped with 1% CHD, water uptake and CHD release were measured. Elastic modulus (E) was calculated from the hardness measurements. There was no significant difference in UTS and Eb between the two materials. However S1 had a higher hardness (30.6 +/- 0.97) and thus E (0.76 MPa) than S2 (hardness = 23.8 +/- 0.48, E = 0.45 MPa). Water uptake for S2 (0.6%) was higher than for S2 (0.1) and addition of CHD dramatically increased the uptake of both (S1 = 3.1%, S2 = 4.0%). Release of CHD was higher for S2 (30%) than S1 (27%). Equating osmotic pressure within the droplets with elastic restraining force gave an extension ratio of 1.95 for S1 and 5.39 for S2. Thus, addition of a hydrophilic agent can compromise the mechanical integrity of low modulus silicones.

  16. Fiber/matrix interfaces for SiC/SiC composites: Multilayer SiC coatings

    Energy Technology Data Exchange (ETDEWEB)

    Halverson, H.; Curtin, W.A. [Virginia Polytechnic Institute and State Univ., Blacksburg, VA (United States)

    1996-08-01

    Tensile tests have been performed on composites of CVI SiC matrix reinforced with 2-d Nicalon fiber cloth, with either pyrolitic carbon or multilayer CVD SiC coatings [Hypertherm High-Temperature Composites Inc., Huntington Beach, CA.] on the fibers. To investigate the role played by the different interfaces, several types of measurements are made on each sample: (i) unload-reload hysteresis loops, and (ii) acoustic emission. The pyrolitic carbon and multilayer SiC coated materials are remarkably similar in overall mechanical responses. These results demonstrate that low-modulus, or compliant, interface coatings are not necessary for good composite performance, and that complex, hierarchical coating structures may possibly yield enhanced high-temperature performance. Analysis of the unload/reload hysteresis loops also indicates that the usual {open_quotes}proportional limit{close_quotes} stress is actually slightly below the stress at which the 0{degrees} load-bearing fibers/matrix interfaces slide and are exposed to atmosphere.

  17. Microstructure, mechanical property, corrosion behavior, and in vitro biocompatibility of Zr-Mo alloys.

    Science.gov (United States)

    Zhou, F Y; Wang, B L; Qiu, K J; Li, L; Lin, J P; Li, H F; Zheng, Y F

    2013-02-01

    In this study, the microstructure, mechanical properties, corrosion behaviors, and in vitro biocompatibility of Zr-Mo alloys as a function of Mo content after solution treatment were systemically investigated to assess their potential use in biomedical application. The experimental results indicated that Zr-1Mo alloy mainly consisted of an acicular structure of α' phase, while ω phase formed in Zr-3Mo alloy. In Zr-5Mo alloy, retained β phase and a small amount of precipitated α phase were observed. Only the retained β phase was obtained in Zr-10Mo alloy. Zr-1Mo alloy exhibited the greatest hardness, bending strength, and modulus among all experimental Zr-Mo alloys, while β phase Zr-10Mo alloy had a low modulus. The results of electrochemical corrosion indicated that adding Mo into Zr improved its corrosion resistance which resulted in increasing the thermodynamic stability and passivity of zirconium. The cytotoxicity test suggested that the extracts of the studied Zr-Mo alloys produced no significant deleterious effect to fibroblast cells (L-929) and osteoblast cells (MG 63), indicating an excellent in vitro biocompatibility. Based on these facts, certain Zr-Mo alloys potentially suitable for different biomedical applications were proposed. Copyright © 2012 Wiley Periodicals, Inc.

  18. Cement-base bearing pads mortar for connections in the precast concrete: study of surface roughness

    Directory of Open Access Journals (Sweden)

    M. K. El Debs

    Full Text Available Bearing pads are used in precast concrete connections to avoid concentrated stresses in the contact area between the precast elements. In the present research, the bearing pads are Portland cement mortar with styrene-butadiene latex (SB, lightweight aggregate (expanded vermiculite-term and short fibers (polypropylene, glass and PVA, in order to obtain a material with low modulus of elasticity and high tenacity, compared with normal Portland cement mortar. The objective of this paper is to analyze the influence of surface roughness on the pads and test other types of polypropylene fibers. Tests were carried out to characterize the composite and test on bearing pads. Characterization tests show compressive strength of 41MPa and modulus of elasticity of 12.8GPa. The bearing pads tests present 30% reduction of stiffness in relation to a reference mortar. The bearing pads with roughness on both sides present a reduction up to 30% in stiffness and an increase in accumulated deformation of more than 120%, regarding bearing pads with both sides smooth.

  19. Effect of Elastic Modulus on Biomechanical Properties of Lumbar Interbody Fusion Cage

    Institute of Scientific and Technical Information of China (English)

    Yue Zhu; Fusheng Li; Shujun Li; Yulin Hao; Rui Yang

    2009-01-01

    This work focuses on the influence of elastic modulus on biomechanical properties of lumbar interbody fusion cages by selecting two titanium alloys with different elastic modulus.They were made by a new β type alloy with chemical composition of Ti-24Nb-4Zr-7.6Sn having low Young's modulus ~50 GPa and by a conventional biomedical alloy Ti-6Al-4V having Young's modulus ~110 GPa.The results showed that the designed cages with low modulus (LMC) and high modulus (HMC) can keep identical compression load ~9.8 kN and endure fatigue cycles higher than 5× 106 without functional or mechanical failure under 2.0 kN axial compression.The anti-subsidence ability of both group cages were examined by axial compression of thoracic spine specimens (T9~T10) dissected freshly from the calf with averaged age of 6 months.The results showed that the LMC has better anti-subsidence ability than the HMC (p<0.05).The above results suggest that the cage with low elastic modulus has great potential for clinical applications.

  20. Fibroblast Adhesion and Proliferation on a New β Type Ti-39Nb-13Ta-4.6Zr Alloy for Biomedical Application

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Cell attachment and spreading on Ti-based alloy surfaces is a major parameter in implant technology. Ti39Nb-13Ta-4.6Zr alloy is a new β type Ti alloy developed for biomedical application. This alloy has low modulus and high strength, which indicates that it can be used for medical purposes such as surgical implants.To evaluate the biocompatibility and effects of the surface morphology of Ti-39Nb-13Ta-4.6Zr on the cellular behaviour, the adhesion and proliferation of rat gingival fibroblasts were studied with substrates having different surface roughness and the results were also compared with commercial pure titanium and Ti-6Al-4V. The results indicate that fibroblast shows similar adhesion and proliferation on the smooth surfaces of commercial pure titanium (Cp Ti), Ti-39Nb-13Ta-4.6Zr, and Ti-6Al-4V, suggesting that Ti-39Nb-13Ta-4.6Zr has similar biocompatibility to Cp Ti and Ti-6Al-4V. The fibroblast adhesion and spreading was lower on rough surfaces of Cp Ti, Ti-39Nb-13Ta-4.6Zr and Ti-6Al-4V than on smooth ones. Surface roughness appeared to be a dominant factor that determines the fibroblast adhesion and proliferation.

  1. Tensile Properties and Microstructure of Inconel 718 Fabricated with Electron Beam Freeform Fabrication (EBF(sup 3))

    Science.gov (United States)

    Bird, R. Keith; Hibberd, Joshua

    2009-01-01

    Electron beam freeform fabrication (EBF3) direct metal deposition processing was used to fabricate two Inconel 718 single-bead-width wall builds and one multiple-bead-width block build. Specimens were machined to evaluate microstructure and room temperature tensile properties. The tensile strength and yield strength of the as-deposited material from the wall and block builds were greater than those for conventional Inconel 718 castings but were less than those for conventional cold-rolled sheet. Ductility levels for the EBF3 material were similar to those for conventionally-processed sheet and castings. An unexpected result was that the modulus of the EBF3-deposited Inconel 718 was significantly lower than that of the conventional material. This low modulus may be associated with a preferred crystallographic orientation resultant from the deposition and rapid solidification process. A heat treatment with a high solution treatment temperature resulted in a recrystallized microstructure and an increased modulus. However, the modulus was not increased to the level that is expected for Inconel 718.

  2. Recent Advancements in Flexible and Stretchable Electrodes for Electromechanical Sensors: Strategies, Materials, and Features.

    Science.gov (United States)

    Zhao, Songfang; Li, Jinhui; Cao, Duxia; Zhang, Guoping; Li, Jia; Li, Kui; Yang, Yang; Wang, Wei; Jin, Yufeng; Sun, Rong; Wong, Ching-Ping

    2017-03-30

    Stretchable and flexible sensors attached onto the surface of the human body can perceive external stimuli, thus attracting extensive attention due to their lightweight, low modulus, low cost, high flexibility, and stretchability. Recently, a myriad of efforts have been devoted to improving the performance and functionality of wearable sensors. Herein, this review focuses on recent remarkable advancements in the development of flexible and stretchable sensors. Multifunction of these wearable sensors is realized by incorporating some desired features (e.g., self-healing, self-powering, linearity, and printing). Next, focusing on the characteristics of carbon nanomaterials, nanostructured metal, conductive polymer, or their hybrid composites, two major strategies (e.g., materials that stretch and structures that stretch) and diverse design approaches have been developed to achieve highly flexible and stretchable electrodes. Strain sensing performances of recently reported sensors indicate that the appropriate choice of geometric engineering as well as intrinsically stretchable materials is essential for high-performance strain sensing. Finally, some important directions and challenges of a fully sensor-integrated wearable platform are proposed to realize their potential applications for human motion monitoring and human-machine interfaces.

  3. Stretchable array of metal nanodisks on a 3D sinusoidal wavy elastomeric substrate for frequency tunable plasmonics

    Science.gov (United States)

    Feng, Di; Zhang, Hui; Xu, Siyi; Tian, Limei; Song, Ningfang

    2017-03-01

    Metal nanostructures integrated with soft, elastomeric substrates provide an unusual platform with capabilities in plasmonic frequency tuning of mechanical strain. In this paper, we have prepared a tunable optical device, dense arrays of plasmonic nanodisks on a low-modulus, and high-elongation elastomeric substrate with a three-dimensional (3D) sinusoidal wavy, and their optical characteristics have been measured and analyzed in detail. Since surface plasmon is located and propagates along metal surfaces with sub-wavelength structures, and those dispersive properties are determined by the coupling strength between the individual structures, in this study, a 3D sinusoidal curve elastomeric substrate is used to mechanically control the inter-nanodisk spacing by applying straining and creating a frequency tunable plasmonic device. Here we study the optical resonance peak shifting generated by stretching this type of flexible device, and the role that 3D sinusoidal curve surface configuration plays in determining the tunable properties. Since only the hybrid dipolar mode has been observed in experiments, the coupled dipole approximation (CDA) method is employed to simulate the optical response of these devices, and the experimental and simulation results show that these devices have high tunability to shift optical resonance peaks at near-infrared wavelengths, which will provide strong potential for new soft optical sensors and wearable plasmonic sensors.

  4. Tribological and thermal stability study of nanoporous amorphous boron carbide films prepared by pulsed plasma chemical vapor deposition

    Science.gov (United States)

    Liza, Shahira; Ohtake, Naoto; Akasaka, Hiroki; Munoz-Guijosa, Juan M.

    2015-06-01

    In this work, the thermal stability and the oxidation and tribological behavior of nanoporous a-BC:H films are studied and compared with those in conventional diamond-like carbon (DLC) films. a-BC:H films were deposited by pulsed plasma chemical vapor deposition using B(CH3)3 gas as the boron source. A DLC interlayer was used to prevent the a-BC:H film delamination produced by oxidation. Thermal stability of a-BC:H films, with no delamination signs after annealing at 500 °C for 1 h, is better than that of the DLC films, which completely disappeared under the same conditions. Tribological test results indicate that the a-BC:H films, even with lower nanoindentation hardness than the DLC films, show an excellent boundary oil lubricated behavior, with lower friction coefficient and reduce the wear rate of counter materials than those on the DLC film. The good materials properties such as low modulus of elasticity and the formation of micropores from the original nanopores during boundary regimes explain this better performance. Results show that porous a-BC:H films may be an alternative for segmented DLC films in applications where severe tribological conditions and complex shapes exist, so surface patterning is unfeasible.

  5. Mutual capacitance of liquid conductors in deformable tactile sensing arrays

    Energy Technology Data Exchange (ETDEWEB)

    Li, Bin [Electrical and Computer Engineering Department, Drexel University, Philadelphia, Pennsylvania 19104 (United States); Fontecchio, Adam K. [Electrical and Computer Engineering and Materials Science and Engineering Departments, Drexel University, Philadelphia, Pennsylvania 19104 (United States); Visell, Yon [Electrical and Computer Engineering Department, Media Arts and Technology, California NanoSystems Institute, University of California, Santa Barbara, California 93106 (United States)

    2016-01-04

    Advances in highly deformable electronics are needed in order to enable emerging categories of soft computing devices ranging from wearable electronics, to medical devices, and soft robotic components. The combination of highly elastic substrates with intrinsically stretchable conductors holds the promise of enabling electronic sensors that can conform to curved objects, reconfigurable displays, or soft biological tissues, including the skin. Here, we contribute sensing principles for tactile (mechanical image) sensors based on very low modulus polymer substrates with embedded liquid metal microfluidic arrays. The sensors are fabricated using a single-step casting method that utilizes fine nylon filaments to produce arrays of cylindrical channels on two layers. The liquid metal (gallium indium alloy) conductors that fill these channels readily adopt the shape of the embedding membrane, yielding levels of deformability greater than 400%, due to the use of soft polymer substrates. We modeled the sensor performance using electrostatic theory and continuum mechanics, yielding excellent agreement with experiments. Using a matrix-addressed capacitance measurement technique, we are able to resolve strain distributions with millimeter resolution over areas of several square centimeters.

  6. The cryogenic bonding evaluation at the metallic-composite interface of a composite overwrapped pressure vessel with additional impact investigation

    Science.gov (United States)

    Clark, Eric A.

    A bonding evaluation that investigated the cryogenic tensile strength of several different adhesives/resins was performed. The test materials consisted of 606 aluminum test pieces adhered to a wet-wound graphite laminate in order to simulate the bond created at the liner-composite interface of an aluminum-lined composite overwrapped pressure vessel. It was found that for cryogenic applications, a flexible, low modulus resin system must be used. Additionally, the samples prepared with a thin layer of cured resin -- or prebond -- performed significantly better than those without. It was found that it is critical that the prebond surface must have sufficient surface roughness prior to the bonding application. Also, the aluminum test pieces that were prepared using a surface etchant slightly outperformed those that were prepared with a grit blast surface finish and performed significantly better than those that had been scored using sand paper to achieve the desired surface finish. An additional impact investigation studied the post impact tensile strength of composite rings in a cryogenic environment. The composite rings were filament wound with several combinations of graphite and aramid fibers and were prepared with different resin systems. The rings were subjected to varying levels of Charpy impact damage and then pulled to failure in tension. It was found that the addition of elastic aramid fibers with the carbon fibers mitigates the overall impact damage and drastically improves the post-impact strength of the structure in a cryogenic environment.

  7. Regression Analysis of the Effect of Bias Voltage on Nano- and Macrotribological Properties of Diamond-Like Carbon Films Deposited by a Filtered Cathodic Vacuum Arc Ion-Plating Method

    Directory of Open Access Journals (Sweden)

    Shojiro Miyake

    2014-01-01

    Full Text Available Diamond-like carbon (DLC films are deposited by bend filtered cathodic vacuum arc (FCVA technique with DC and pulsed bias voltage. The effects of varying bias voltage on nanoindentation and nanowear properties were evaluated by atomic force microscopy. DLC films deposited with DC bias voltage of −50 V exhibited the greatest hardness at approximately 50 GPa, a low modulus of dissipation, low elastic modulus to nanoindentation hardness ratio, and high nanowear resistance. Nanoindentation hardness was positively correlated with the Raman peak ratio Id/Ig, whereas wear depth was negatively correlated with this ratio. These nanotribological properties highly depend on the films’ nanostructures. The tribological properties of the FCVA-DLC films were also investigated using a ball-on-disk test. The average friction coefficient of DLC films deposited with DC bias voltage was lower than that of DLC films deposited with pulse bias voltage. The friction coefficient calculated from the ball-on-disk test was correlated with the nanoindentation hardness in dry conditions. However, under boundary lubrication conditions, the friction coefficient and specific wear rate had little correlation with nanoindentation hardness, and wear behavior seemed to be influenced by other factors such as adhesion strength between the film and substrate.

  8. Designing functionally graded materials with superior load-bearing properties.

    Science.gov (United States)

    Zhang, Yu; Sun, Ming-Jie; Zhang, Denzil

    2012-03-01

    Ceramic prostheses often fail from fracture and wear. We hypothesize that these failures may be substantially mitigated by an appropriate grading of elastic modulus at the ceramic surface. In this study, we elucidate the effect of elastic modulus profile on the flexural damage resistance of functionally graded materials (FGMs), providing theoretical guidelines for designing FGMs with superior load-bearing property. The Young's modulus of the graded structure is assumed to vary in a power-law relation with a scaling exponent n; this is in accordance with experimental observations from our laboratory and elsewhere. Based on the theory for bending of graded beams, we examine the effect of n value and bulk-to-surface modulus ratio (E(b)/E(s)) on stress distribution through the graded layer. Theory predicts that a low exponent (0.15graded materials with various n values and E(b)/E(s) ratios can be fabricated by infiltrating alumina and zirconia with a low-modulus glass. Flexural tests show that graded alumina and zirconia with suitable values of these parameters exhibit superior load-bearing capacity, 20-50% higher than their homogeneous counterparts. Improving load-bearing capacity of ceramic materials could have broad impacts on biomedical, civil, structural, and an array of other engineering applications.

  9. Analytical design model for a piezo-composite unimorph actuator and its verification using lightweight piezo-composite curved actuators

    Science.gov (United States)

    Yoon, K. J.; Park, K. H.; Lee, S. K.; Goo, N. S.; Park, H. C.

    2004-06-01

    This paper describes an analytical design model for a layered piezo-composite unimorph actuator and its numerical and experimental verification using a LIPCA (lightweight piezo-composite curved actuator) that is lighter than other conventional piezo-composite type actuators. The LIPCA is composed of top fiber composite layers with high modulus and low CTE (coefficient of thermal expansion), a middle PZT ceramic wafer, and base layers with low modulus and high CTE. The advantages of the LIPCA design are to replace the heavy metal layer of THUNDER by lightweight fiber-reinforced plastic layers without compromising the generation of high force and large displacement and to have design flexibility by selecting the fiber direction and the number of prepreg layers. In addition to the lightweight advantage and design flexibility, the proposed device can be manufactured without adhesive layers when we use a resin prepreg system. A piezo-actuation model for a laminate with piezo-electric material layers and fiber composite layers is proposed to predict the curvature and residual stress of the LIPCA. To predict the actuation displacement of the LIPCA with curvature, a finite element analysis method using the proposed piezo-actuation model is introduced. The predicted deformations are in good agreement with the experimental ones.

  10. Melt compounding with graphene to develop functional, high-performance elastomers

    Science.gov (United States)

    Araby, Sherif; Zaman, Izzuddin; Meng, Qingshi; Kawashima, Nobuyuki; Michelmore, Andrew; Kuan, Hsu-Chiang; Majewski, Peter; Ma, Jun; Zhang, Liqun

    2013-04-01

    Rather than using graphene oxide, which is limited by a high defect concentration and cost due to oxidation and reduction, we adopted cost-effective, 3.56 nm thick graphene platelets (GnPs) of high structural integrity to melt compound with an elastomer—ethylene-propylene-diene monomer rubber (EPDM)—using an industrial facility. An elastomer is an amorphous, chemically crosslinked polymer generally having rather low modulus and fracture strength but high fracture strain in comparison with other materials; and upon removal of loading, it is able to return to its original geometry, immediately and completely. It was found that most GnPs dispersed uniformly in the elastomer matrix, although some did form clusters. A percolation threshold of electrical conductivity at 18 vol% GnPs was observed and the elastomer thermal conductivity increased by 417% at 45 vol% GnPs. The modulus and tensile strength increased by 710% and 404% at 26.7 vol% GnPs, respectively. The modulus improvement agrees well with the Guth and Halpin-Tsai models. The reinforcing effect of GnPs was compared with silicate layers and carbon nanotube. Our simple fabrication would prolong the service life of elastomeric products used in dynamic loading, thus reducing thermosetting waste in the environment.

  11. ENHANCED MECHANICAL PROPERTIES OF POLYPROPYLENE/SILICA NANOCOMPOSITES WITH SURFACE MODIFICATION OF NANO-SILICA VIA IN SITU COPOLYMERIZATION OF METHYL METHACRYLATE AND BUTYL ACRYLATE

    Institute of Scientific and Technical Information of China (English)

    Jing-zhi Zheng; Xing-ping Zhou; Ji-ru Ying; Xiao-lin Xie

    2009-01-01

    Nano-sized silica particles were modified with methacryloxy-propyltrimethoxysilane(MPS)followed by in situ copolymerization of methyl methacrylate(MMA)and butyl acrylate(BA).These modified nanoparticles were compounded with polypropylene(PP)to prepare PP/silica nanocomposites.PMMA grafted on nano-silica enhances the dispersion of the nanoparticles and interfacial adhesion,decreases the size of PP spherulites in nanocomposites and leads to increasing the Young's modulus and toughness of PP/silica nanocomposites at the same time.PBA grafted on nano-silica further improves the dispersion and the interfacial interaction,decreases the size of PP spherulites in PP/silica nanocomposite and leads to further toughening the PP/silica nanocomposite.But,its low modulus decreases the modulus of the PP/silica nanocomposite.The nanocomposites with PP and nano-silica particles modified by P(MMA-co-BA)have balanced stiffness and toughness due to the moderate modulus and solubility parameter of P(MMA-co-BA).

  12. Development of a Thermoplastic Magnesia Carbon Brick——"A Cold Process Flexible System"

    Institute of Scientific and Technical Information of China (English)

    R.Mishra; S.Mukhopadhyay

    2006-01-01

    Conventional resin bonded MgO-C bricks, which are manufactured via cold mixing process, harden and attain brittleness during carbonization of resin due to the formation of isotropic glassy carbon. They do not exhibit thermo-plasticity, which can facilitate the release of huge amount of stresses generated during preheating or in operation. On the contrary, pitch bonded MgO-C bricks, show better pyro-plasticity due to formation of an anisotropic and graphitized coke structure during carbonization of pitch. Hence, pitch bonded bricks show a superior structural spalling resistance in comparison to resin-bonded bricks. One of the drawbacks of pitch-bonded bricks is that the manufacturing requires a hot mixing process and hot pressing facility. This paper describes how a combination of above two processes was optimized to make a MgO-C brick via cold process. These bricks exhibit a low Modulus of Elasticity and thereby facilitate release of stresses during operation. Normal coal tar pitch is considered as an environmental hazard due to the presence of polyaromatic hydrocarbons like benzopyrene B [ a ] P. So, a special binder with a low B [ a ] P was selected, which is eco-friendly in nature. Such bricks were made in our plant in China and supplied to an integrated steel plant in Europe for their ladle. The bricks supplied have given encouraging life.

  13. Interfacial stability and electrochemical behavior of Li/LiFePO4 batteries using novel soft and weakly adhesive photo-ionogel electrolytes

    Science.gov (United States)

    Aidoud, D.; Etiemble, A.; Guy-Bouyssou, D.; Maire, E.; Le Bideau, J.; Guyomard, D.; Lestriez, B.

    2016-10-01

    We have developed flexible polymer-gel electrolytes based on a polyacrylate cross-linked matrix that confines an ionic liquid doped with a lithium salt. Free-standing solid electrolyte membrane is obtained after UV photo-polymerization of acrylic monomers dissolved inside the ionic liquid/lithium salt mixture. The liquid precursor of the photo-ionogel may also be directly deposited onto porous composite electrode, which results in all-solid state electrode/electrolyte stacking after UV illumination. Minor variations in the polymer component of the electrolyte formulation significantly affect the electrochemical behavior in LiFePO4/lithium and lithium/lithium cells. The rate performance increases with an increase of the ionic conductivity, which decreases with the polymer content and decreases with increasing oxygen content in the polyacrylate matrix. Their fairly low modulus endow them weak and beneficial pressure-sensitive-adhesive character. X-Rays Tomography shows that the solid-state photo-ionogel electrolytes keep their integrity upon cycling and that their surface remains smooth. The coulombic efficiency of LiFePO4/lithium cells increases with an increase of the adhesive strength of the photo-ionogel, suggesting a relationship between the contact intimacy at the lithium/photo-ionogel interface and the efficiency of the lithium striping/plating. In lithium/lithium cells, only the photo-ionogels with the higher adhesion strength are able to allow the reversible striping/plating of lithium.

  14. Composite flywheel material design for high-speed energy storage

    Directory of Open Access Journals (Sweden)

    Michael A. Conteh

    2016-06-01

    Full Text Available Lamina and laminate mechanical properties of materials suitable for flywheel high-speed energy storage were investigated. Low density, low modulus and high strength composite material properties were implemented for the constant stress portion of the flywheel while higher density, higher modulus and strength were implemented for the constant thickness portion of the flywheel. Design and stress analysis were used to determine the maximum energy densities and shape factors for the flywheel. Analytical studies along with the use of the CADEC-online software were used to evaluate the lamina and laminate properties. This study found that a hybrid composite of M46J/epoxy–T1000G/epoxy for the flywheel exhibits a higher energy density when compared to known existing flywheel hybrid composite materials such as boron/epoxy–graphite/epoxy. Results from this study will contribute to further development of the flywheel that has recently re-emerged as a promising application for energy storage due to significant improvements in composite materials and technology.

  15. Influence of cell shape on mechanical properties of Ti-6Al-4V meshes fabricated by electron beam melting method.

    Science.gov (United States)

    Li, S J; Xu, Q S; Wang, Z; Hou, W T; Hao, Y L; Yang, R; Murr, L E

    2014-10-01

    Ti-6Al-4V reticulated meshes with different elements (cubic, G7 and rhombic dodecahedron) in Materialise software were fabricated by additive manufacturing using the electron beam melting (EBM) method, and the effects of cell shape on the mechanical properties of these samples were studied. The results showed that these cellular structures with porosities of 88-58% had compressive strength and elastic modulus in the range 10-300MPa and 0.5-15GPa, respectively. The compressive strength and deformation behavior of these meshes were determined by the coupling of the buckling and bending deformation of struts. Meshes that were dominated by buckling deformation showed relatively high collapse strength and were prone to exhibit brittle characteristics in their stress-strain curves. For meshes dominated by bending deformation, the elastic deformation corresponded well to the Gibson-Ashby model. By enhancing the effect of bending deformation, the stress-strain curve characteristics can change from brittle to ductile (the smooth plateau area). Therefore, Ti-6Al-4V cellular solids with high strength, low modulus and desirable deformation behavior could be fabricated through the cell shape design using the EBM technique. Copyright © 2014 Acta Materialia Inc. All rights reserved.

  16. The influence of cell morphology on the compressive fatigue behavior of Ti-6Al-4V meshes fabricated by electron beam melting.

    Science.gov (United States)

    Zhao, S; Li, S J; Hou, W T; Hao, Y L; Yang, R; Misra, R D K

    2016-06-01

    Additive manufacturing technique is a promising approach for fabricating cellular bone substitutes such as trabecular and cortical bones because of the ability to adjust process parameters to fabricate different shapes and inner structures. Considering the long term safe application in human body, the metallic cellular implants are expected to exhibit superior fatigue property. The objective of the study was to study the influence of cell shape on the compressive fatigue behavior of Ti-6Al-4V mesh arrays fabricated by electron beam melting. The results indicated that the underlying fatigue mechanism for the three kinds of meshes (cubic, G7 and rhombic dodecahedron) is the interaction of cyclic ratcheting and fatigue crack growth on the struts, which is closely related to cumulative effect of buckling and bending deformation of the strut. By increasing the buckling deformation on the struts through cell shape design, the cyclic ratcheting rate of the meshes during cyclic deformation was decreased and accordingly, the compressive fatigue strength was increased. With increasing bending deformation of struts, fatigue crack growth in struts contributed more to the fatigue damage of meshes. Rough surface and pores contained in the struts significantly deteriorated the compressive fatigue strength of the struts. By optimizing the buckling and bending deformation through cell shape design, Ti-6Al-4V alloy cellular solids with high fatigue strength and low modulus can be fabricated by the EBM technique. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. [A preliminary study on the mechanical characteristics of the titanium scaffolds with three-dimensional mesh structure fabricated by electron beam melting].

    Science.gov (United States)

    Yan, R Z; Li, Y F; Wang, C; Li, R X; Liu, Z W; Hu, M

    2016-11-09

    Objective: To examine the biomechanical properties of three-dimensional(3D) printed electron beam melting(EBM) Ti-6Al-4V mesh as scaffold for mandibular repairment. Methods: We fabricated Ti-6Al-4V samples of different structures with strut, sheet and 3D mesh scaffolds(a controllable diameter 0.35, 0.50, 0.70 mm, distribution density: intensive sparse) by EBM process. The mechanical properties of these structures were examined by X-ray energy dispersive spectrum(EDS), uniaxial tensile test, three-point bending test, under compression load and compared with their different microstructure and mechanical properties. Results: Compressive deformation behavior of these cellular structures exhibited brittle character that had a typical irregular plateau region in the stress-strain curves. The mesh of larger diameter(d=0.70 mm) showed higher specific strength than the meshs of small diameter(d=0.35 mm) did, and the other 3D mesh under the same condition showed identical specific stiffness. Conclusions: EBM was successfully used to fabricate novel 3D mesh Ti-6Al-4V structures for applications. By optimizing the buckling and bending deformation, Ti-6Al-4V cellular solids with high strength, low modulus. Furthermore, the results of mechanical property and chemistry composition showed that the scaffold could completely satisfy the requirement of hard tissue repairment.

  18. Peculiar aging response of near b Ti-25 Nb-2Mo-4Sn alloy for biomedical applications

    Institute of Scientific and Technical Information of China (English)

    Shun Guo; Bin Chen; Qingkun Meng; Ruiwen Zhao; Xinqing Zhao

    2013-01-01

    In this paper, aging response of a recently developed near b Ti-25Nb-2Mo-4Sn (wt%) alloy with high strength and low modulus was investigated intensively. The experimental results from X-ray diffraction and transmission electron microscopy showed that the aging production of the Ti-2524 alloy was (bþo) or (bþa) even under the same aging treatment condition, depending on the pre-treatments prior to the aging. Solid evidence confirmed the competition between stable a phase and metastable o phase during the decomposition of b phase on aging. Different aging response of Ti-2524 alloy can be attributed to high-density dislocations and grain boundaries which suppress the formation of o, and alternatively promote a phase formation. This provides a thermo-mechanical approach to inhibit deleterious o phase formation and assist fine a phase precipitation. Upon an appropriate aging treatment, superior mechanical properties of high ultimate tensile strength (1233 MPa) and low elastic modulus (77 GPa) were achieved in Ti-2524 alloy.

  19. Mechanical behavior of carbon-carbon composites

    Science.gov (United States)

    Rozak, G. A.

    1984-01-01

    A general background, test plan, and some results of preliminary examinations of a carbon-carbon composite material are presented with emphasis on mechanical testing and inspection techniques. Experience with testing and evaluation was gained through tests of a low modulus carbon-carbon material, K-Karb C. The properties examined are the density - 1.55 g/cc; four point flexure strength in the warp - 137 MPa (19,800 psi) and the fill - 95.1 MPa (13,800 psi,) directions; and the warp interlaminar shear strength - 14.5 MPa (2100 psi). Radiographic evaluation revealed thickness variations and the thinner areas of the composite were scrapped. The ultrasonic C-scan showed attenuation variations, but these did not correspond to any of the physical and mechanical properties measured. Based on these initial tests and a survey of the literature, a plan has been devised to examine the effect of stress on the oxidation behavior, and the strength degradation of coated carbon-carbon composites. This plan will focus on static fatigue tests in the four point flexure mode in an elevated temperature, oxidizing environment.

  20. Stretchable, multiplexed pH sensors with demonstrations on rabbit and human hearts undergoing ischemia.

    Science.gov (United States)

    Chung, Hyun-Joong; Sulkin, Matthew S; Kim, Jong-Seon; Goudeseune, Camille; Chao, Hsin-Yun; Song, Joseph W; Yang, Sang Yoon; Hsu, Yung-Yu; Ghaffari, Roozbeh; Efimov, Igor R; Rogers, John A

    2014-01-01

    Stable pH is an established biomarker of health, relevant to all tissues of the body, including the heart. Clinical monitoring of pH in a practical manner, with high spatiotemporal resolution, is particularly difficult in organs such as the heart due to its soft mechanics, curvilinear geometry, heterogeneous surfaces, and continuous, complex rhythmic motion. The results presented here illustrate that advanced strategies in materials assembly and electrochemical growth can yield interconnected arrays of miniaturized IrOx pH sensors encapsulated in thin, low-modulus elastomers to yield conformal monitoring systems capable of noninvasive measurements on the surface of the beating heart. A thirty channel custom data acquisition system enables spatiotemporal pH mapping with a single potentiostat. In vitro testing reveals super-Nernstian sensitivity with excellent uniformity (69.9 ± 2.2 mV/pH), linear response to temperature (-1.6 mV °C(-1) ), and minimal influence of extracellular ions (sensor arrays on balloon catheters and on skin-like stretchable membranes. Real-time measurement of pH on the surfaces of explanted rabbit hearts and a donated human heart during protocols of ischemia-reperfusion illustrate some of the capabilities. Envisioned applications range from devices for biological research, to surgical tools and long-term implants.