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Sample records for hot wire method

  1. Application of Hot-wire Method for Measuring Thermal Conductivity of Fine Ceramics

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    Shangxi WANG

    2016-11-01

    Full Text Available Ceramic substrate is preferred in high density packaging due to its high electrical resistivity and moderate expansion coefficient. The thermal conductivity is a key parameter for packaging substrates. There are two common methods to measure the thermal conductivity, which are the hot-wire method and the laser-flash method. Usually, the thermal conductivities of porcelain is low and meet the measurement range of hot-wire method, and the measured value by hot-wire method has little difference with that by laser-flash method. In recent years, with the requirement of high-powered LED lighting, some kinds of ceramic substrates with good thermal conductivity have been developed and their thermal conductivity always measured by the means of laser flash method, which needs expensive instrument. In this paper, in order to detect the thermal conductivity of fine ceramic with convenience and low cost, the feasibility of replacing the laser flash method with hot wire method to measure thermal conductivity of ceramic composites was studied. The experiment results showed that the thermal conductivity value of fine ceramics measured by the hot-wire method is severely lower than that by the laser-flash method. However, there is a positive relationship between them. It is possible to measure the thermal conductivity of fine ceramic workpiece instantly by hot-wire method via a correction formula.DOI: http://dx.doi.org/10.5755/j01.ms.22.4.12543

  2. Novel Gas Barrier SiOC Coating to PET Bottles through a Hot Wire CVD Method

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    Masaki Nakaya

    2016-01-01

    Full Text Available In an attempt to enhance the gas barrier enhancement of plastic containers such as poly(ethylene terephthalate bottles, a novel method was found using a hot wire CVD technique, where tantalum wire is heated and exposed to a gas flow of vinyl silane. The resultant SiOC thin film was confirmed to characteristically contain Si-Si bonds in its surface and demonstrate a remarkably and highly practical decrease of the permeation of various gas through poly(ethylene terephthalate bottles.

  3. Further elucidation of nanofluid thermal conductivity measurement using a transient hot-wire method apparatus

    Science.gov (United States)

    Yoo, Donghoon; Lee, Joohyun; Lee, Byeongchan; Kwon, Suyong; Koo, Junemo

    2017-08-01

    The Transient Hot-Wire Method (THWM) was developed to measure the absolute thermal conductivity of gases, liquids, melts, and solids with low uncertainty. The majority of nanofluid researchers used THWM to measure the thermal conductivity of test fluids. Several reasons have been suggested for the discrepancies in these types of measurements, including nanofluid generation, nanofluid stability, and measurement challenges. The details of the transient hot-wire method such as the test cell size, the temperature coefficient of resistance (TCR) and the sampling number are further investigated to improve the accuracy and consistency of the measurements of different researchers. It was observed that smaller test apparatuses were better because they can delay the onset of natural convection. TCR values of a coated platinum wire were measured and statistically analyzed to reduce the uncertainty in thermal conductivity measurements. For validation, ethylene glycol (EG) and water thermal conductivity were measured and analyzed in the temperature range between 280 and 310 K. Furthermore, a detailed statistical analysis was conducted for such measurements, and the results confirmed the minimum number of samples required to achieve the desired resolution and precision of the measurements. It is further proposed that researchers fully report the information related to their measurements to validate the measurements and to avoid future inconsistent nanofluid data.

  4. Further elucidation of nanofluid thermal conductivity measurement using a transient hot-wire method apparatus

    Science.gov (United States)

    Yoo, Donghoon; Lee, Joohyun; Lee, Byeongchan; Kwon, Suyong; Koo, Junemo

    2018-02-01

    The Transient Hot-Wire Method (THWM) was developed to measure the absolute thermal conductivity of gases, liquids, melts, and solids with low uncertainty. The majority of nanofluid researchers used THWM to measure the thermal conductivity of test fluids. Several reasons have been suggested for the discrepancies in these types of measurements, including nanofluid generation, nanofluid stability, and measurement challenges. The details of the transient hot-wire method such as the test cell size, the temperature coefficient of resistance (TCR) and the sampling number are further investigated to improve the accuracy and consistency of the measurements of different researchers. It was observed that smaller test apparatuses were better because they can delay the onset of natural convection. TCR values of a coated platinum wire were measured and statistically analyzed to reduce the uncertainty in thermal conductivity measurements. For validation, ethylene glycol (EG) and water thermal conductivity were measured and analyzed in the temperature range between 280 and 310 K. Furthermore, a detailed statistical analysis was conducted for such measurements, and the results confirmed the minimum number of samples required to achieve the desired resolution and precision of the measurements. It is further proposed that researchers fully report the information related to their measurements to validate the measurements and to avoid future inconsistent nanofluid data.

  5. Hot-Wire Calibration at Low Velocities: Revisiting the Vortex Shedding Method

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    Sohrab S. Sattarzadeh

    2013-01-01

    Full Text Available The necessity to calibrate hot-wire probes against a known velocity causes problems at low velocities, due to the inherent inaccuracy of pressure transducers at low differential pressures. The vortex shedding calibration method is in this respect a recommended technique to obtain calibration data at low velocities, due to its simplicity and accuracy. However, it has mainly been applied in a low and narrow Reynolds number range known as the laminar vortex shedding regime. Here, on the other hand, we propose to utilize the irregular vortex shedding regime and show where the probe needs to be placed with respect to the cylinder in order to obtain unambiguous calibration data.

  6. Measurements of thermal conductivity and thermal diffusivity of hen egg-white lysozyme crystals using a short hot wire method

    Science.gov (United States)

    Fujiwara, Seiji; Maki, Syou; Tanaka, Seiichi; Maekawa, Ryunosuke; Masuda, Tomoki; Hagiwara, Masayuki

    2017-07-01

    Thermal conductivity and thermal diffusivity of hen egg-white lysozyme (HEWL) crystals were examined by using the transient short hot wire method. This method is based on the conventional hot wire method, but improved by using a wire that is much shorter than conventional ones. The magneto-Archimedes levitation technique was utilized to attach the HEWL crystals onto the wire. Owing to the upward magnetic force, the HEWL crystals were deposited at the air-liquid interface of the protein buffer solution where the short hot wire was preliminarily fixed. In situ observation clarified that the wire was completely buried into the HEWL crystals. By means of these techniques, the measurement of thermal conductivity and thermal diffusivity of HEWL crystals was realized for the first time. Gadolinium chloride (a paramagnetic subject) was used as a precipitant agent of crystallization. Crystal growth was carried out over 20 h at 17.2 °C. The applied magnetic field was 4 T. Measurements were conducted during the crystal growth at two different times. The thermal conductivity and diffusivity of the HEWL crystals were determined to be 0.410 W/(m.K) and 3.77×10-8 m2/s at 14 h after, and 0.438 W/(m.K) and 5.18×10-8 m2/s at 20 h after, respectively. We emphasize that this method is versatile and applicable for other protein crystals.

  7. A Hot-Wire Method Based Thermal Conductivity Measurement Apparatus for Teaching Purposes

    Science.gov (United States)

    Alvarado, S.; Marin, E.; Juarez, A. G.; Calderon, A.; Ivanov, R.

    2012-01-01

    The implementation of an automated system based on the hot-wire technique is described for the measurement of the thermal conductivity of liquids using equipment easily available in modern physics laboratories at high schools and universities (basically a precision current source and a voltage meter, a data acquisition card, a personal computer…

  8. A hot-wire method based thermal conductivity measurement apparatus for teaching purposes

    Science.gov (United States)

    Alvarado, S.; Marín, E.; Juárez, A. G.; Calderón, A.; Ivanov, R.

    2012-07-01

    The implementation of an automated system based on the hot-wire technique is described for the measurement of the thermal conductivity of liquids using equipment easily available in modern physics laboratories at high schools and universities (basically a precision current source and a voltage meter, a data acquisition card, a personal computer and a high purity platinum wire). The wire, which is immersed in the investigated sample, is heated by passing a constant electrical current through it, and its temperature evolution, ΔT, is measured as a function of time, t, for several values of the current. A straightforward methodology is then used for data processing in order to obtain the liquid thermal conductivity. The start point is the well known linear relationship between ΔT and ln(t) predicted for long heating times by a model based on a solution of the heat conduction equation for an infinite lineal heat source embedded in an infinite medium into which heat is conducted without convective and radiative heat losses. A criterion is used to verify that the selected linear region is the one that matches the conditions imposed by the theoretical model. As a consequence the method involves least-squares fits in linear, semi-logarithmic (semi-log) and log-log graphs, so that it becomes attractive not only to teach about heat transfer and thermal properties measurement techniques, but also as a good exercise for students of undergraduate courses of physics and engineering learning about these kinds of mathematical functional relationships between variables. The functionality of the experiment was demonstrated by measuring the thermal conductivity in samples of liquids with well known thermal properties.

  9. Note: effect of the tilting angle of the wire on the onset of natural convection in the transient hot wire method.

    Science.gov (United States)

    Lee, Seung-Hyun; Jang, Seok Pil

    2012-07-01

    In this paper, numerical and experimental investigations are systematically performed to identify the effect of the tilting angle of the wire on the onset of natural convection in the transient hot wire method (THWM), a widely accepted technique for measuring the thermal conductivity of various media, especially nanofluids. To validate our numerical simulation code, the numerical results are compared with theoretical solutions as well as with experimental results. Based on the results, we show that the onset time of natural convection in THWM decreases rapidly with the increase of the wire's tilting angle from vertical position. Also, we systematically show the effect of the wire's tilting angle on the linear region, which is a suitable measurement interval, and on the measurement error of THWM.

  10. Measurement of the Arithmetic Mean Velocity of a Pulsating Flow of High Velocity by the Hot-Wire Method

    Science.gov (United States)

    1946-04-01

    8217 . . those resulting from the heat $ ransfer chara?-- a" teristics .of the hot..wire ar,eedesired andltiakes it possible, in combination.trith the basid...Wires at Constant-Resistance Operation If constant resistance of the hot- wire, or zero rate of increase of heat energy -in the wire,- dH/dt = 0, is...assumed, the balance of energies supplied to, and dissipated by, the hot wire may be expressed by King’s equation (references 1 and 2). NACA TX

  11. Design and Development of Embedded System for the Measurement of Thermal Conductivity of Liquids by Transient Hot Wire Method

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    Nagamani GOSALA

    2011-06-01

    Full Text Available Thermal conductivity of polymers is an important property for both polymer applications and processing industry. The successful application of thermal insulating fluids in the last several years has demonstrated that such fluids can effectively control the heat loss. Understanding and controlling the thermal environment for oilfield operations has been a concern and research topic. As a consequence of this trend, there is huge demand for new methods of instrumentation to evaluate the performance of material properties and characterization. The main aim of the present study is the development of hardware and software for measuring the thermal conductivity of liquids using transient hot wire method. Because of the relatively short experimental times and large amounts of parametric data involved in the measurement process, embedded control of the measurement is essential. The experimental implementation requires a suitable temperature sensing, automatic control, data acquisition, and data analysis systems accomplished using an embedded system that has been built around the ARM LPC 2103 mixed signal controller.

  12. Hot-wire calibration in subsonic/transonic flow regimes

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    Nagabushana, K. A.; Ash, Robert L.

    1995-01-01

    A different approach for calibrating hot-wires, which simplifies the calibration procedure and reduces the tunnel run-time by an order of magnitude was sought. In general, it is accepted that the directly measurable quantities in any flow are velocity, density, and total temperature. Very few facilities have the capability of varying the total temperature over an adequate range. However, if the overheat temperature parameter, a(sub w), is used to calibrate the hot-wire then the directly measurable quantity, voltage, will be a function of the flow variables and the overheat parameter i.e., E = f(u,p,a(sub w), T(sub w)) where a(sub w) will contain the needed total temperature information. In this report, various methods of evaluating sensitivities with different dependent and independent variables to calibrate a 3-Wire hot-wire probe using a constant temperature anemometer (CTA) in subsonic/transonic flow regimes is presented. The advantage of using a(sub w) as the independent variable instead of total temperature, t(sub o), or overheat temperature parameter, tau, is that while running a calibration test it is not necessary to know the recovery factor, the coefficients in a wire resistance to temperature relationship for a given probe. It was deduced that the method employing the relationship E = f (u,p,a(sub w)) should result in the most accurate calibration of hot wire probes. Any other method would require additional measurements. Also this method will allow calibration and determination of accurate temperature fluctuation information even in atmospheric wind tunnels where there is no ability to obtain any temperature sensitivity information at present. This technique greatly simplifies the calibration process for hot-wires, provides the required calibration information needed in obtaining temperature fluctuations, and reduces both the tunnel run-time and the test matrix required to calibrate hotwires. Some of the results using the above techniques are presented

  13. Simplified Transient Hot-Wire Method for Effective Thermal Conductivity Measurement in Geo Materials: Microstructure and Saturation Effect

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    B. Merckx

    2012-01-01

    Full Text Available The thermal conductivity measurement by a simplified transient hot-wire technique is applied to geomaterials in order to show the relationships which can exist between effective thermal conductivity, texture, and moisture of the materials. After a validation of the used “one hot-wire” technique in water, toluene, and glass-bead assemblages, the investigations were performed (1 in glass-bead assemblages of different diameters in dried, water, and acetone-saturated states in order to observe the role of grain sizes and saturation on the effective thermal conductivity, (2 in a compacted earth brick at different moisture states, and (3 in a lime-hemp concrete during 110 days following its manufacture. The lime-hemp concrete allows the measurements during the setting, desiccation and carbonation steps. The recorded Δ/ln( diagrams allow the calculation of one effective thermal conductivity in the continuous and homogeneous fluids and two effective thermal conductivities in the heterogeneous solids. The first one measured in the short time acquisitions (<1 s mainly depends on the contact between the wire and grains and thus microtexture and hydrated state of the material. The second one, measured for longer time acquisitions, characterizes the mean effective thermal conductivity of the material.

  14. Application of hot-wire technique at unconventional conditions

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    Lebiga, V. A.; Pak, A. Yu.; Zinoviev, V. N.; Mironov, D. S.

    2017-10-01

    The problems of using the hot-wire method for studying fluctuations in flows are considered when standard approaches and conventional modes cannot be used due to constraints caused either by the flow parameters or by the characteristics and conditions of the experiments. Examples of measurements under conditions of extremely low pressures and beyond the limits of the continuity of the medium in the CO2-laser are given; The use of data of hot-wire measurements for the determination of sources of disturbances in test sections of high-speed wind tunnels is shown; the design of a probe for measurement of concentration of components of the binary gas mixture is described, etc.

  15. Measurements of Thermal Conductivity and Thermal Diffusivity of Hen Egg-White Lysozyme Crystals and Its Solution Using the Transient Short Hot Wire Method

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    Fujiwara, Seiji; Maki, Syou; Maekawa, Ryunosuke; Tanaka, Seiichi; Hagiwara, Masayuki

    2017-08-01

    Protein crystals are an essentially important biological sample to advance the analysis of X-ray structure, but their thermophysical properties, especially thermal conductivity and thermal diffusivity, have not been studied sufficiently. This current situation can be attributed to various kinds of technical problems; e.g., the fragility of protein crystals and the difficulty of nucleation control. Ideally speaking, protein crystallization should be carried out under a " containerless condition" to eliminate any mechanical distortion of the crystals from the walls. To realize the condition, we have developed an original crystallization method by means of the magneto-Archimedes effect. In this paper, a transient short hot wire method was combined with the technique of magneto-Archimedes effect to realize simultaneous measurement of thermal conductivity and thermal diffusivity of hen egg-white lysozyme (HEWL) crystals. As the results, thermal conductivity and thermal diffusivity of HEWL crystals were found to be 0.410-0.438 \\hbox {W}\\cdot \\hbox {m}^{-1}\\cdot \\hbox {K}^{-1} and 3.77-5.18× 10^{-8} \\hbox {m}2\\cdot \\hbox {s}^{-1}, respectively. We clarified by the crystallizing process of HEWL that the crystals were magnetically levitated at the air-liquid interface and the short hot wire was completely buried into them as the crystals grew. We also measured the HEWL solution by the same methods. The thermal conductivity of the solution had almost the same value as that of water and had little dependency on the concentration of HEWL, but the thermal diffusivity was unclear.

  16. Hot-Film and Hot-Wire Anemometry for a Boundary Layer Active Flow Control Test

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    Lenahan, Keven C.; Schatzman, David M.; Wilson, Jacob Samuel

    2013-01-01

    Unsteady active flow control (AFC) has been used experimentally for many years to minimize bluff-body drag. This technology could significantly improve performance of rotorcraft by cleaning up flow separation. It is important, then, that new actuator technologies be studied for application to future vehicles. A boundary layer wind tunnel was constructed with a 1ft-x-3ft test section and unsteady measurement instrumentation to study how AFC manipulates the boundary layer to overcome adverse pressure gradients and flow separation. This unsteady flow control research requires unsteady measurement methods. In order to measure the boundary layer characteristics, both hot-wire and hot-film Constant Temperature Anemometry is used. A hot-wire probe is mounted in the flow to measure velocity while a hot-film array lays on the test surface to measure skin friction. Hot-film sensors are connected to an anemometer, a Wheatstone bridge circuit with an output that corresponds to the dynamic flow response. From this output, the time varying flow field, turbulence, and flow reversal can be characterized. Tuning the anemometers requires a fan test on the hot-film sensors to adjust each output. This is a delicate process as several variables drastically affect the data, including control resistance, signal input, trim, and gain settings.

  17. Uncertainties in hot-wire measurements of compressible turbulent flows implied by comparisons with laser-induced fluorescence

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    Mckenzie, R. L.; Logan, P.

    1986-01-01

    A hot-wire anemometer and a new nonintrusive laser-induced fluorescence (LIF) technique are used to survey a Mach 2 turbulent boundary layer. The hot-wire anemometer's ability to accurately measure mass flux, temperature, and density fluctuations in a compressible flow is examined by comparing its results with those obtained using LIF. Several methods of hot-wire calibration are used, and the uncertainties in their measurements of various fluctuating flow parameters are determined. The results show that although a hot-wire operated at high overheat can measure mass flux fluctuations, temperature and density fluctuations are not determined accurately from such measurements. However, a hot-wire operated at multiple overheats can be used to measure static and total temperature fluctuations. The presence of pressure fluctuations and their correlation with density can prevent the use of hot-wire data to determine density fluctuations.

  18. Basic ideas and concepts in hot wire anemometry: an experimental approach for introductory physics students

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    El Abed, Mohamed

    2016-01-01

    The purpose of hot wire anemometry is to measure the speed of an air stream. The classical method is based on the measure of the value of a temperature dependant resistor inserted in a Wheatstone bridge (Lomas 1986 Fundamentals of Hot Wire Anemometry (Cambridge: Cambridge University Press)). In this paper we exhibit the physics behind this method and show that by using a wire whose resistance does not vary on the field of temperature explored (from 20 °C to 200 °C), it is however possible to make accurate measurements. Finally, limitations of the method are discussed.

  19. Hot-wire accuracy in supersonic turbulence from comparisons with laser-induced fluorescence

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    Logan, Pamela; Bershader, Daniel; Mckenzie, Robert L.

    1988-01-01

    A hot-wire anemometer and a new, nonintrusive, laser-induced fluorescence (LIF) technique are used to survey a turbulent boundary layer in a supersonic channel flow at Mach no. 2.06. The purpose is to test the accuracy of using the hot wire to measure the fluctuation amplitudes of static temperature and density in a compressible turbulent flow by comparing the results with independent and direct LIF measurements. Several methods of hot-wire calibration and analysis are applied. With each method, the hot-wire response can be related primarily to fluctuations of mass flux and total temperature, from which fluctuations of static temperature and density are calculated. However, these calculations are shown to be valid only if the fluctuations in static pressure are negligible. The acquisition and the analysis of the hot-wire data are often simplified further by neglecting the effects of fluctuations in total temperature. Comparisons of the fluctuation amplitudes of temperature and density obtained by hot-wire and LIF measurements demonstrate that such assumptions might not always be warranted, even in apparently simple flows.

  20. Modelling and operation of sub-miniature constant temperature hot-wire anemometry

    Science.gov (United States)

    Samie, M.; Watmuff, J. H.; Van Buren, T.; Hutchins, N.; Marusic, I.; Hultmark, M.; Smits, A. J.

    2016-12-01

    High-Reynolds number flows are very common in technological applications and in nature, and hot-wire anemometry is the preferred method for measuring the time-series of fluctuating velocity in such flows. However, measurement of very high-Reynolds number flows requires hot-wires with higher temporal and spatial resolution than is available with conventional probes. Much effort has therefore been devoted to decreasing the size of the hot-wire probes and this has led to associated challenges with operation. It is this latter operation problem which is the focus of this paper. To this end, an existing theoretical model of constant-temperature hot-wire anemometers (Perry 1982 Hot-Wire Anemometry (New York: Oxford University Press), Watmuff 1995 Exp. Therm. Fluid Sci. 11 117-34) is applied, and its accuracy is tested for the first time by comparison to measurements using an in-house constant temperature anemometer (CTA) for both conventional 5~μ m-diameter wires and sub-miniature hot-wires. With the aid of this model, we propose modifications to the CTA design and demonstrate successful operation of the CTA with the Princeton nano-scale thermal anemometry probe (NSTAP) (Bailey et al 2010 J. Fluid Mech. 663 160-79). It is also shown that the transfer function obtained from the model can be utilized to estimate the true frequency response and cut-off frequency of a hot-wire-CTA system to the velocity fluctuations, which is essential in accurate measurements of energy spectrum and higher order statistics of turbulent flows.

  1. Investigation on Characterizing Heated Pulsating Flows with Hot Wire Anemometers - A Hands-On Approach

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    Marius Alexandru PANAIT

    2014-06-01

    Full Text Available The pulsating heated flows are traditionally a difficult subject to treat with conventional hot wire or film methods. Special factors that complicate matters are flow reversal and non linear flow effects of vortices and wire probe wake disturbances on the heat transfer to the hot film or wire sensor in heated pulsating flows. The presence of these strongly nonlinear and unknown terms leads to great difficulties in calibration of hot film probes in this particular regime. The paper analyses the current state of matters in the field and reports a series of solutions that have been practically tested in a case of a high speed pulsated heated flow. Normally such measurements are made in a non-contact fashion using a LDV system or various visualization techniques but there have been recent attempts to use a constant temperature hot wire anemometer system (CTA.To obtain meaningful calibration for hot wire films in hot pulsating flows, a comparison system on other principles (LDV was used, as well as a specially designed nozzle to replace the calibrator unit that could not be operated with heated fluid due to structural integrity reasons. The method as described below works well for the expected speed range that could be generated using the special nozzle.

  2. An in-situ calibration technique for four-wire hot-wire probe in conjunction for atmospheric studies

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    Sadr, Reza; Singha, Arindam

    2011-11-01

    There is an increasing need to resolve the small-scales of atmospheric turbulence in order to estimate the higher order statistics of the turbulent flow. Sonic anemometers are commonly used in atmospheric research; however their application can only provide data with low special and temporal resolution. Hot-wire (HW) probes are still the best tool to obtain turbulent statistics with high temporal and spatial resolution. But HW probes are rarely used for atmospheric measurement due to the intricacy and logistical difficulties associated with the calibration and applications of the required probes for this flow field. In the present study, an in-situ method of calibration of a four-wire hot-wire anemometer is proposed, which bypasses the need for prior calibration. A proper data reduction algorithm has been developed to be used in conjunction with the four-wire probe. The proposed methodology enables one to use the hot-wire anemometer for atmospheric measurement to obtain three dimensional velocity information, at high spatial and temporal resolution, without the necessity of going through extensive calibration procedure. The feasibility of this method has been tested in laboratory and Monte Carlo simulation has been used to establish the stability and sensitivity of the data reduction algorithm.

  3. On the Humidity Sensitivity of Hot-Wire Measurements

    DEFF Research Database (Denmark)

    Larsen, Søren Ejling; Busch, N. E.

    1980-01-01

    The influence of humidity changes on hot-wire measurements is discussed. Indications are that the humidity sensitivity parameters obtained by the authors in an earlier paper should be changed. This means, however, that the agreement between predicted and measured sensitivities ceases to exist...

  4. Dual wire welding torch and method

    Science.gov (United States)

    Diez, Fernando Martinez; Stump, Kevin S.; Ludewig, Howard W.; Kilty, Alan L.; Robinson, Matthew M.; Egland, Keith M.

    2009-04-28

    A welding torch includes a nozzle with a first welding wire guide configured to orient a first welding wire in a first welding wire orientation, and a second welding wire guide configured to orient a second welding wire in a second welding wire orientation that is non-coplanar and divergent with respect to the first welding wire orientation. A method of welding includes moving a welding torch with respect to a workpiece joint to be welded. During moving the welding torch, a first welding wire is fed through a first welding wire guide defining a first welding wire orientation and a second welding wire is fed through a second welding wire guide defining a second welding wire orientation that is divergent and non-coplanar with respect to the first welding wire orientation.

  5. Turbulence measurements in a swirling confined jet flowfield using a triple hot-wire probe

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    Janjua, S. I.; Mclaughlin, D. K.

    1982-01-01

    An axisymmetric swirling confined jet flowfield, similar to that encountered in gas turbine combustors was investigated using a triple hot-wire probe. The raw data from the three sensors were digitized using ADC's and stored on a Tektronix 4051 computer. The data were further reduced on the computer to obtain time-series for the three instantaneous velocity components in the flowfield. The time-mean velocities and the turbulence quantities were deduced. Qualification experiments were performed and where possible results compared with independent measurements. The major qualification experiments involved measurements performed in a non-swirling flow compared with conventional X-wire measurements. In the swirling flowfield, advantages of the triple wire technique over the previously used multi-position single hot-wire method are noted. The measurements obtained provide a data base with which the predictions of turbulence models in a recirculating swirling flowfield can be evaluated.

  6. Hot-wire assisted ALD of tungsten films: In-situ study of the interplay between CVD, etching, and ALD modes

    NARCIS (Netherlands)

    Yang, Mengdi; Aarnink, Antonius A.I.; Kovalgin, Alexeij Y.; Wolters, Robertus A.M.; Schmitz, Jurriaan

    2015-01-01

    In this work, we investigated an approach of hot-wire assisted ALD (HWALD), utilizing a hot (up to 2000 8C) tungsten (W) wire. Tungsten films were deposited by this method using alternating pulses of WF6 gas and atomic hydrogen (at-H). The latter was generated by catalytic dissociation of molecular

  7. A strategy to eliminate all nonlinear effects in constant-voltage hot-wire anemometry

    Science.gov (United States)

    Berson, Arganthaël; Blanc-Benon, Philippe; Comte-Bellot, Geneviève

    2009-04-01

    A constant-voltage anemometer is subject to nonlinear effects when the operating hot wire is exposed to large velocity fluctuations in the incident flow. This results in the generation of undesirable higher harmonics, just as in the two classic systems, constant-current and constant-temperature anemometers, for which no attempts are normally made to correct the nonlinearities. The present investigation shows that these undesirable higher harmonics can be suppressed in the case of a constant-voltage anemometer. A new approach to process experimental data is proposed. It is based on three explicit equations established and solved with all terms included, i.e., without linearization. These are (1) the first-order differential equation that describes the electronic circuit of a constant-voltage anemometer—this equation permits to deduce the instantaneous resistance of the hot wire from the output voltage of the anemometer; (2) the first-order differential equation that expresses the thermal lag behavior of the hot wire when used in a constant-voltage mode—this equation permits to restore the instantaneous resistance that an ideal wire would have without thermal inertia in the same flow conditions; and (3) the algebraic relation that expresses the heat-transfer law of an ideal wire, according to King's law, a look-up table, or a polynomial fit—this relation permits to deduce the instantaneous flow velocity from the instantaneous resistance of the ideal wire. The proposed method is easily implemented on a personal computer and permits odd turbulence moments, such as skewness factors, to be obtained satisfactorily.

  8. High Reynolds Number Effects on Multi-Hole Probes and Hot Wire Anemometers

    Science.gov (United States)

    Ramachandran, N.; Smith, A.; Gerry, G.; Kauffman, W.

    1995-01-01

    The paper reports on the results from an experimental investigation of the response of multi-hole and hot wire probes at high flow Reynolds numbers (Re approx. 10(exp 6)). The limited results available in literature for 5-hole probes are restricted to Re approx. 10(exp 4). The experiment aims to investigate the probe response (in terms of dimensionless pressure ratios, characterizing pitch, and yaw angles and the total and static pressures) at high Re values and to gauge their effect on the calculated velocity vector. Hot wire calibrations were also undertaken with a parametric variation of the flow pressure, velocity and temperature. Different correction and calibration schemes are sought to be tested against the acquired data set. The data is in the analysis stage at the present time. The test provided good benchmark quality data that can be used to test future calibration and testing methods.

  9. A new tubular hot-wire CVD for diamond coating

    Science.gov (United States)

    Motahari, Hamid; Bellah, Samad Moemen; Malekfar, Rasoul

    2017-06-01

    A new tubular hot-wire chemical vapor deposition (HWCVD) system using a tubular quartz vacuum chamber has been fabricated. The filaments in this system can heat the substrate and act as a gas activator and thermally activator for gas species at the same time. The nano- and microcrystalline diamond coatings on the surface of steel AISI 316 substrates have been grown. To assess the results, SEM and FESEM images and Raman spectroscopy investigations have been applied. The results reveal that micro- and nanocrystalline diamond structures have been formed in the coatings, but the disordered diamond and some non-diamond phases, such as graphitic carbons, are also present in the coating layers. The analytical measurements show the growth of diamond films with well-faceted crystals in (111) direction. However, intrinsic stress, secondary nucleation, and poor adhesion are the main issues of future research for this new designed HWCVD.

  10. Determination of the heat transfer for a hot-wire with the use of the Couette flow

    Science.gov (United States)

    Lebiga, V. A.; Zinoviev, V. N.; Pak, A. Yu.; Zharov, I. R.

    2017-10-01

    The modeling of the Couette flow in a circular gap between coaxial cylinders is considered, including rarefied gas conditions at large Knudsen numbers. When developing the experimental facility for this purpose, the geometric sizes were determined taking into account minimum deviation of the velocity profile in the gap from the linear one in the case of laminar flow regime, and also to prevent the formation of Taylor-Görtler vortices with the chosen flow parameters. A series of tests was performed using the hot-wire at atmospheric pressure. It was cofirmed the operability of the facility itself and satisfactory matching of the hot-wire calibration data using the proposed method in the Couette flow and standard data obtained in the DISA calibration wind tunnel. Preliminary data for influence the Knudsen number on the heat transfer between the hot-wire probe and flow.

  11. Hot wire deposited hydrogenated amorphous silicon solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Mahan, A.H.; Iwaniczko, E.; Nelson, B.P.; Reedy, R.C. Jr.; Crandall, R.S. [National Renewable Energy Lab., Golden, CO (United States)

    1996-05-01

    This paper details the results of a study in which low H content, high deposition rate hot wire (HW) deposited amorphous silicon (a-Si:H) has been incorporated into a substrate solar cell. The authors find that the treatment of the top surface of the HW i layer while it is being cooled from its high deposition temperature is crucial to device performance. They present data concerning these surface treatments, and correlate these treatments with Schottky device performance. The authors also present first generation HW n-i-p solar cell efficiency data, where a glow discharge (GD) {mu}c-Si(p) layer was added to complete the partial devices. No light trapping layer was used to increase the device Jsc. Their preliminary investigations have yielded efficiencies of up to 6.8% for a cell with a 4000 {Angstrom} thick HW i-layer, which degrade less than 10% after a 900 hour light soak. The authors suggest avenues for further improvement of their devices.

  12. Hot wire and spark pyrolysis as simple new routes to silicon nanoparticle synthesis

    CSIR Research Space (South Africa)

    Scriba, MR

    2012-11-01

    Full Text Available gases, silane and diborane or silane and phosphine were used. While hot wire pyrolysis always results in multifaceted particles, those produced by spark pyrolysis are spherical. Electrical resistance measurements of compressed powders showed that boron...

  13. A thermo-electro-mechanical simulation model for hot wire cutting of EPS foam

    DEFF Research Database (Denmark)

    Petkov, Kiril; Hattel, Jesper Henri

    2016-01-01

    A one-dimensional thermo-electro-mechanical mathematical model describing the effects taking place within a Ni-Cr20% wire used in a hot-wire cutting process for free forming and rapid prototyping of expanded polystyrene (EPS) is investigated and simulated. The model implements and solves three se...

  14. Rethinking the participatory web : A history of HotWired's 'new publishing paradigm,' 1994-1997

    NARCIS (Netherlands)

    Stevenson, Michael

    2014-01-01

    This article critically interrogates key assumptions in popular web discourse by revisiting an early example of web “participation.” Against the claim that Web 2.0 technologies ushered in a new paradigm of participatory media, I turn to the history of HotWired, Wired magazine’s ambitious web-only

  15. PERSPECTIVES OF MODERNIZATION OF WIRE MILL OF HOT ROLLING 150 AT RUP “BMZ”

    Directory of Open Access Journals (Sweden)

    A. V. Gontarj

    2004-01-01

    Full Text Available The offered modernization of the mill presumes the increase of capacity of the small-sort wire mill of hot milling 150 approximately till 40% at reduction of cost of the produced on it rolled wire by 15%, that will allow in future as well to grow the volumes of hardware production.

  16. Experimental investigation of near-wall effects on hot-wire measurements

    Energy Technology Data Exchange (ETDEWEB)

    Durst, F.; Zanoun, E.S. [Institute of Fluid Mechanics, Friedrich-Alexander-University, Erlangen-Nuernberg Cauerstr. 4, 91058 Erlangen (Germany)

    2002-07-01

    Hot-wire anemometry is a well-established measuring technique in modern fluid mechanics and is widely used to study laminar and turbulent flows. However, unsolved problems still exist when measurements are carried out close to heat-conducting or heat-insulating walls. Additional heat losses occur because of the presence of the wall that are usually not accounted for in the calibration of the wire. Because of this, erroneous fluid velocity measurements result with hot wires if the presence of the wall is not taken into account. The present paper investigates the effect that the wall material has on these additional heat losses from hot wires for walls of different heat conductivities. Similarity analysis of various aspects of the problem, verified by experimental and numerical results, is presented for wall materials of different heat conductivities, and the results are compared with available data in the literature. The data confirm the expected increase in heat losses with increasing wall heat conductivity. For heat-insulating materials the authors' results show that a wall-thickness influence exists. Additional data are provided to show that the heat loss from hot wires increases with increasing wire overheating, and the influence of the wire diameter is also clarified. (orig.)

  17. Tandem solar cells deposited using hot-wire chemical vapor deposition

    NARCIS (Netherlands)

    Veen, M.K. van

    2003-01-01

    In this thesis, the application of the hot-wire chemical vapor deposition (HWCVD) technique for the deposition of silicon thin films is described. The HWCVD technique is based on the dissociation of silicon-containing gasses at the catalytic surface of a hot filament. Advantages of this technique

  18. USING HOT WIRE TECHNIQUE FOR MEASURING THERMAL CONDUCTIVITY OF INFUSIONS OF ORGANIC AND CONVENTIONAL COFFEE

    Directory of Open Access Journals (Sweden)

    Fernando Gordillo-Delgado

    2016-07-01

    Full Text Available The technique of hot wire, a versatile method of low cost and high accuracy for measuring the thermal conductivity of fluids through the increasing temperature of a wire that is immersed into the liquid and between its ends a potential difference is abruptly applied. Using well-known conductivity liquids: water, ethylene glycol and glycerine, the system was tested and calibrated. In this work, this procedure was used to measure the thermal conductivity of the infusion samples of organic and conventional coffee. The same roast degree of the beans was verified with a colorimeter and the preparation was made by pressing 22g of coffee powder in 110mL of water. The obtained data were subjected to Analysis of Variance (ANOVA and this confirmed that the differences in the thermophysical parameter in the two samples are significant with a confidence level of 95\\%. On this way, it was proved that the thermal conductivity value of the coffee infusion allows differentiate between organic and conventional coffee.

  19. Growth Process Conditions of Tungsten Oxide Thin Films Using Hot-Wire Chemical Vapor Deposition

    NARCIS (Netherlands)

    Houweling, Z.S.|info:eu-repo/dai/nl/251874486; Geus, J.W.; de Jong, M.; Harks, P.P.R.M.L.; van der Werf, C.H.M.; Schropp, R.E.I.|info:eu-repo/dai/nl/072502584

    2011-01-01

    We report the growth conditions of nanostructured tungsten oxide (WO3−x) thin films using hot-wire chemical vapor deposition (HWCVD). Two tungsten filaments were resistively heated to various temperatures and exposed to an air flow at various subatmospheric pressures. The oxygen partial pressure was

  20. Optoelectronic properties of hot-wire silicon layers deposited at 100 °C

    NARCIS (Netherlands)

    Brinza, M.|info:eu-repo/dai/nl/304823325; van der Werf, C.H.M.; Rath, J.K.|info:eu-repo/dai/nl/304830585; Schropp, R.E.I.|info:eu-repo/dai/nl/072502584

    2008-01-01

    Hot-wire chemical vapor deposition is employed for the deposition of amorphous and microcrystalline silicon layers at substrate temperature kept below 100 °C with the aid of active cooling of the substrate holder. The hydrogen dilution is varied in order to investigate films at the

  1. Electrically active, doped monocrystalline silicon nanoparticles produced by hot wire thermal catalytic pyrolysis

    CSIR Research Space (South Africa)

    Scriba, MR

    2011-05-01

    Full Text Available Doped silicon nanoparticles have successfully been produced by hot wire thermal catalytic pyrolysis at 40 mbar and a filament temperature of 1800 °C, using a mixture of silane and diborane or phosphine. All particles are monocrystalline with shapes...

  2. Composition and crystallinity of silicon nanoparticles synthesised by hot wire thermal catalytic pyrolysis at different pressures

    CSIR Research Space (South Africa)

    Scriba, MR

    2009-04-01

    Full Text Available The effect of pressure on the structure and composition of silicon nanoparticles synthesized by hot wire thermal catalytic pyrolysis (HW-TCP) of pure silane has been investigated. Light brown powders were produced at silane pressures of 10 and 50...

  3. Ultrafast deposition of silicon nitride and semiconductor silicon thin films by Hot Wire Chemical Vapor Deposition

    NARCIS (Netherlands)

    Schropp, R.E.I.; van der Werf, C.H.M.; Verlaan, V.; Rath, J.K.; Li, H. B. T.

    2009-01-01

    The technology of Hot Wire Chemical Vapor Deposition (HWCVD) or Catalytic Chemical Vapor Deposition (Cat-CVD) has made great progress during the last couple of years. This review discusses examples of significant progress. Specifically, silicon nitride deposition by HWCVD (HW-SiNx) is highlighted,

  4. Hot wire chemical vapor deposition: recent progress, present state of the art and competitive opportunities

    NARCIS (Netherlands)

    Schropp, R.E.I.|info:eu-repo/dai/nl/072502584

    2009-01-01

    Hot Wire CVD (also called Catalytic CVD or initiated CVD) is an elegant low pressure deposition technique for the deposition of functional films, both inorganic and organic, based on the decomposition of precursor sources at a heated metallic surface. The conformal deposition of thin films on rigid

  5. Silicon nitride at high growth rate using hot wire chemical vapor deposition

    NARCIS (Netherlands)

    Verlaan, V.

    2008-01-01

    Amorphous silicon nitride (SiNx) is a widely studied alloy with many commercial applications. This thesis describes the application of SiNx deposited at high deposition rate using hot wire chemical vapor deposition (HWCVD) for solar cells and thin film transistors (TFTs). The deposition process of

  6. Hot wire needle probe for thermal conductivity detection

    Science.gov (United States)

    Condie, Keith Glenn; Rempe, Joy Lynn; Knudson, Darrell lee; Daw, Joshua Earl; Wilkins, Steven Curtis; Fox, Brandon S.; Heng, Ban

    2015-11-10

    An apparatus comprising a needle probe comprising a sheath, a heating element, a temperature sensor, and electrical insulation that allows thermal conductivity to be measured in extreme environments, such as in high-temperature irradiation testing. The heating element is contained within the sheath and is electrically conductive. In an embodiment, the heating element is a wire capable of being joule heated when an electrical current is applied. The temperature sensor is contained within the sheath, electrically insulated from the heating element and the sheath. The electrical insulation electrically insulates the sheath, heating element and temperature sensor. The electrical insulation fills the sheath having electrical resistance capable of preventing electrical conduction between the sheath, heating element, and temperature sensor. The control system is connected to the heating element and the temperature sensor.

  7. Employing Hot Wire Anemometry to Directly Measure the Water Balance in a Proton Exchange membrane Fuel Cell

    DEFF Research Database (Denmark)

    Shakhshir, Saher Al; Hussain, Nabeel; Berning, Torsten

    2015-01-01

    Water management in proton exchange membrane fuel cells (PEMFC’s) remains a critical problem for their durability, cost, and performance. Because the anode side of this fuel cell has the tendency to become dehydrated, measuring the water balance can be an important diagnosis tool during fuel cell...... operation. The water balance indicates how much of the product water leaves at the anode side versus the cathode side. Previous methods of determining the fuel cell water balance often relied on condensing the water in the exhaust gas streams and weighing the accumulated mass which is a time consuming...... process that has limited accuracy. Currently, our group is developing a novel method to accurately determine the water balance in a PEMFC in real time by employing hot-wire anemometry. The amount of heat transferred from the wire to the anode exhaust stream can be translated into a voltage signal which...

  8. Study of Flow Deformation around Wind-Vane Mounted Three-Dimensional Hot-Wire Probes

    DEFF Research Database (Denmark)

    Rømer Rasmussen, K.; Larsen, Søren Ejling; Jørgensen, F. E.

    1981-01-01

    Open wind tunnel tests on several different sensor systems consisting of triaxial hot-wire probes mounted on wind vanes (DISA and Riso vanes) have shown that flow deformation around the hot-wire sensor introduces errors in the measured velocity components. Though changes in the horizontal...... components proved to be negligible, flow deformation resulted in an overestimation of the vertical component from 1.1 to 1.5, depending on the direction of the vertical component. Turbulence and mean value data were adjusted by use of a linear correction derived from the wind tunnel tests. Wind vane...... construction must strike a compromise between minor flow disturbance and sufficient probe support. The final version of the DISA vane resulted in an acceptable vertical correction of about 10%....

  9. Influence of hot-pressing on MgB{sub 2}/Nb/Monel wires

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J.H., E-mail: KIM.Jungho@nims.go.j [Superconducting Materials Center, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan); Institute for Superconducting and Electronic Materials, University of Wollongong, Northfields Avenue, Wollongong, NSW 2522 (Australia); Matsumoto, A. [Superconducting Materials Center, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan); Maeda, M. [Institute for Superconducting and Electronic Materials, University of Wollongong, Northfields Avenue, Wollongong, NSW 2522 (Australia); Yamada, Y.; Wada, K.; Tachikawa, K. [School of Engineering, Tokai University, 1117 Kitakaname, Hiratsuka, Kanagawa 259-1292 (Japan); Rindfleisch, M.; Tomsic, M. [Hyper Tech Research, Incorporated, 1275 Kinnear Road, Columbus, OH 43212 (United States); Kumakura, H. [Superconducting Materials Center, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan)

    2010-11-01

    Uniaxial hot-pressing was applied as an alternative way to further improve the grain connectivity of both un-doped and carbon doped MgB{sub 2}/Nb/Monel wires. In this study, hot-pressing of 100 MPa resulted in the improvement of the mass density, the critical current density, and the grain connectivity of the wires. However, this also caused additional critical current density anisotropy, which is associated with the texture of a- and b-axes oriented grains. In particular, the anisotropy factors of critical current density for the un-doped and the carbon doped conductors were estimated to be 2.6 and 1.7, respectively, under an external magnetic field of 14 T.

  10. EBSD analysis of tungsten-filament carburization during the hot-wire CVD of multi-walled carbon nanotubes

    CSIR Research Space (South Africa)

    Oliphant, CJ

    2014-02-01

    Full Text Available Filament condition during hot-wire chemical vapor deposition conditions of multi-walled carbon nanotubes is a major concern for a stable deposition process. We report on the novel application of electron backscatter diffraction to characterize...

  11. The influence of precursor gas pressure on structure and properties of fluoropolymer coatings by hot wire CVD

    Directory of Open Access Journals (Sweden)

    Safonov Alexey

    2017-01-01

    Full Text Available In this paper we investigated the deposition process of the fluoropolymer coatings by the method of Hot Wire Chemical Vapor Deposition. The dependence of precursor gas pressure on deposition rate, structure and properties of the formed film was investigated. The study has shown that the increasing of precursor gas pressure leads to change of the film structure from porous to continuous with globules and further to solid that have different wettability. Depending on the mode of deposition was obtained the fluoropolymer coating with different structure: the wetting angle changed from 60 to 170°. A mechanism of the formation of fluoropolymer coating was discussed.

  12. The influence of precursor gas pressure on structure and properties of fluoropolymer coatings by hot wire CVD

    Science.gov (United States)

    Safonov, Alexey; Sulyaeva, Veronica; Kubrak, Konstantin; Starinsky, Sergey; Timoshenko, Nikolay

    2017-10-01

    In this paper we investigated the deposition process of the fluoropolymer coatings by the method of Hot Wire Chemical Vapor Deposition. The dependence of precursor gas pressure on deposition rate, structure and properties of the formed film was investigated. The study has shown that the increasing of precursor gas pressure leads to change of the film structure from porous to continuous with globules and further to solid that have different wettability. Depending on the mode of deposition was obtained the fluoropolymer coating with different structure: the wetting angle changed from 60 to 170°. A mechanism of the formation of fluoropolymer coating was discussed.

  13. A Thermal Analysis of a Hot-Wire Probe for Icing Applications

    Science.gov (United States)

    Struk, Peter M.; Rigby, David L.; Venkataraman, Krishna

    2014-01-01

    This paper presents a steady-state thermal model of a hot-wire instrument applicable to atmospheric measurement of water content in clouds. In this application, the power required to maintain the wire at a given temperature is used to deduce the water content of the cloud. The model considers electrical resistive heating, axial conduction, convection to the flow, radiation to the surroundings, as well as energy loss due to the heating, melting, and evaporation of impinging liquid and or ice. All of these parameters can be varied axially along the wire. The model further introduces a parameter called the evaporation potential which locally gauges the maximum fraction of incoming water that evaporates. The primary outputs of the model are the steady-state power required to maintain a spatially-average constant temperature as well as the variation of that temperature and other parameters along the wire. The model is used to understand the sensitivity of the hot-wire performance to various flow and boundary conditions including a detailed comparison of dry air and wet (i.e. cloud-on) conditions. The steady-state power values are compared to experimental results from a Science Engineering Associates (SEA) Multi-Element probe, a commonly used water-content measurement instrument. The model results show good agreement with experiment for both dry and cloud-on conditions with liquid water content. For ice, the experimental measurements under read the actual water content due to incomplete evaporation and splashing. Model results, which account for incomplete evaporation, are still higher than experimental results where the discrepancy is attributed to splashing mass-loss which is not accounted in the model.

  14. Applying hot-wire anemometry to directly measure the water balance in a proton exchange membrane fuel cell

    DEFF Research Database (Denmark)

    Al Shakhshir, Saher; Andreasen, Søren Juhl; Berning, Torsten

    2016-01-01

    In order to better understand and more accurately measure the water balance in a proton exchange membrane fuel cell, our group has recently proposed to apply hot wire anemometry in the fuel cell's anode outlet. It was theoretically shown that the electrical signal obtained from the hot wire sensor...... can be directly converted into the fuel cell water balance. In this work an ex-situ experimental investigation is performed to examine the effect of the wire diameter and the outlet pipe diameter on the voltage signal. For a laboratory fuel cell where the mass flow rate the anode outlet is small......, it is found important to use a small output pipe diameter to obtain a sufficiently strong convection effect and hence clear voltage readings. Depending on the hot wire diameter and the inner pipe diameter, the resulting values for the exponent of the Reynolds number Re in the determination of the Nusselt...

  15. Doped zinc oxide films grown by hot-wire chemical vapour deposition

    Energy Technology Data Exchange (ETDEWEB)

    Abrutis, A., E-mail: adulfas.abrutis@chf.vu.lt; Silimavicius, L.; Kubilius, V.; Murauskas, T.; Saltyte, Z.; Plausinaitiene, V.

    2015-02-02

    Hot-wire chemical vapour deposition (CVD) was applied to grow zinc oxide (ZnO)-based transparent conducting oxide films. Indium (In)-, gallium (Ga)-, and aluminium (Al)-doped ZnO films were deposited at 400 °C on sapphire-R, Si (100) and glass substrates using a cold wall pulsed liquid injection CVD system containing nichrome wires installed in front of the substrate holder. Zn, In, Al 2,2,6,6-tetramethyl-3,5-heptanedionates, and Ga 3,5-pentanedionate dissolved in 1,2-dimethoxyethane were used as precursors. Hall measurements were performed to evaluate the resistivity, carrier concentration, and carrier mobility in doped ZnO films grown on sapphire substrates at wire currents of 6 A and 9 A. The influence of the dopant type, doping level, substrate, and wire heating current on crystallinity and the electrical and optical properties of the films was investigated and discussed. The best electrical properties were obtained for Al- and Ga-doped films grown at 9 A wire current (resistivity ≈ 1 × 10{sup −3} Ωcm, carrier mobility ≈ 50 cm{sup 2} V{sup −1} s{sup −1} and carrier concentration ≈ 1 × 10{sup 20} cm{sup −3}). The films exhibited a high transmittance in the mid-infrared region (≈ 90% at 2.5 μm). Additional annealing of the films at 400 °C in a mixture of Ar and hydrogen (10%) resulted in the increase in carrier concentration and mobility and in the reduction of film resistivity. - Highlights: • Hot-wire CVD process was applied for the growth of In-, Ga-, and Al-doped ZnO films. • Electrical and optical properties of as-deposited and annealed films were investigated. • Significant influence of film orientation on electrical properties was observed. • Films exhibited high carrier mobility (50–60 cm{sup 2} V{sup −1} s{sup −1}) and low resistivity (≤ 10{sup −3} Ωcm). • Films had high transmittance (~ 90%) in the mid-IR spectral range (at 2.5 μm)

  16. Creation of subsonic macro-and microjets facilities and automated measuring system (AMS-2) for the spatial - temporal hot - wire anemometric visualization of jet flow field

    Science.gov (United States)

    Sorokin, A. M.; Grek, G. R.; Gilev, V. M.; Zverkov, I. D.

    2017-10-01

    Macro-and microjets facilities for generation of the round and plane subsonic jets are designed and fabricated. Automated measuring system (AMS - 2) for the spatial - temporal hot - wire anemometric visualization of jet flow field is designed and fabricated. Coordinate device and unit of the measurement, collecting, storage and processing of hot - wire anemometric information were integrated in the AMS. Coordinate device is intended for precision movement of the hot - wire probe in jet flow field according to the computer program. At the same time accuracy of the hot - wire probe movement is 5 microns on all three coordinates (x, y, z). Unit of measurement, collecting, storage and processing of hot - wire anemometric information is intended for the hot - wire anemometric measurement of the jet flow field parameters (registration of the mean - U and fluctuation - u' characteristics of jet flow velocity), their accumulation and preservation in the computer memory, and also carries out their processing according to certain programms.

  17. Airflow Measurement of the Car HVAC Unit Using Hot-wire Anemometry

    Directory of Open Access Journals (Sweden)

    Fojtlín Miloš

    2016-01-01

    Full Text Available Thermal environment in a vehicular cabin significantly influence drivers’ fatigue and passengers’ thermal comfort. This environment is traditionally managed by HVAC cabin system that distributes air and modifies its properties. In order to simulate cabin thermal behaviour, amount of the air led through car vents must be determined. The aim of this study was to develop methodology to measure airflow from the vents, and consequently calculate corresponding air distribution coefficients. Three climatic cases were selected to match European winter, summer, and spring / fall conditions. Experiments were conducted on a test vehicle in a climatic chamber. The car HVAC system was set to automatic control mode, and the measurements were executed after the system stabilisation—each case was independently measured three times. To be able to evaluate precision of the method, the airflow was determined at the system inlet (HVAC suction and outlet (each vent, and the total airflow values were compared. The airflow was calculated by determining a mean value of the air velocity multiplied by an area of inlet / outlet cross-section. Hot-wire anemometry was involved to measure the air velocity. Regarding the summer case, total airflow entering the cabin was around 57 l s-1 with 60 % of the air entering the cabin through dashboard vents; no air was supplied to the feet compartment. The remaining cases had the same total airflow of around 42 l s-1, and the air distribution was focused mainly on feet and windows. The inlet and outlet airflow values show a good match with a maximum mass differential of 8.3 %.

  18. Airflow Measurement of the Car HVAC Unit Using Hot-wire Anemometry

    Science.gov (United States)

    Fojtlín, Miloš; Planka, Michal; Fišer, Jan; Pokorný, Jan; Jícha, Miroslav

    2016-03-01

    Thermal environment in a vehicular cabin significantly influence drivers' fatigue and passengers' thermal comfort. This environment is traditionally managed by HVAC cabin system that distributes air and modifies its properties. In order to simulate cabin thermal behaviour, amount of the air led through car vents must be determined. The aim of this study was to develop methodology to measure airflow from the vents, and consequently calculate corresponding air distribution coefficients. Three climatic cases were selected to match European winter, summer, and spring / fall conditions. Experiments were conducted on a test vehicle in a climatic chamber. The car HVAC system was set to automatic control mode, and the measurements were executed after the system stabilisation—each case was independently measured three times. To be able to evaluate precision of the method, the airflow was determined at the system inlet (HVAC suction) and outlet (each vent), and the total airflow values were compared. The airflow was calculated by determining a mean value of the air velocity multiplied by an area of inlet / outlet cross-section. Hot-wire anemometry was involved to measure the air velocity. Regarding the summer case, total airflow entering the cabin was around 57 l s-1 with 60 % of the air entering the cabin through dashboard vents; no air was supplied to the feet compartment. The remaining cases had the same total airflow of around 42 l s-1, and the air distribution was focused mainly on feet and windows. The inlet and outlet airflow values show a good match with a maximum mass differential of 8.3 %.

  19. Interchip link system using an optical wiring method.

    Science.gov (United States)

    Cho, In-Kui; Ryu, Jin-Hwa; Jeong, Myung-Yung

    2008-08-15

    A chip-scale optical link system is presented with a transmitter/receiver and optical wire link. The interchip link system consists of a metal optical bench, a printed circuit board module, a driver/receiver integrated circuit, a vertical cavity surface-emitting laser/photodiode array, and an optical wire link composed of plastic optical fibers (POFs). We have developed a downsized POF and an optical wiring method that allows on-site installation with a simple annealing as optical wiring technologies for achieving high-density optical interchip interconnection within such devices. Successful data transfer measurements are presented.

  20. Hot wire anemometer measurements in the unheated air flow tests of the SRB nozzle-to-case joint

    Science.gov (United States)

    Ramachandran, N.

    1988-01-01

    Hot-Wire Anemometer measurements made in the Solid Rocket Booster (SRB) nozzle-to-case joint are discussed. The study was undertaken to glean additional information on the circumferential flow induced in the SRB nozzle joint and the effect of this flow on the insulation bonding flaws. The tests were conducted on a full-scale, 2-D representation of a 65-in long segment of the SRB nozzle joint, with unheated air as the working fluid. Both the flight Mach number and Reynolds number were matched simultaneously and different pressure gradients imposed along the joint face were investigated. Hot-wire anemometers were used to obtain velocity data for different joint gaps and debond configurations. The procedure adopted for hot-wire calibration and use is outlined and the results from the tests summarized.

  1. Hot Wire CVD for thin film triple junction cells and for ultrafast deposition of the SiN passivation layer on polycrystalline Si solar cells

    NARCIS (Netherlands)

    Schropp, R.E.I.; Franken, R.H.; Goldbach, H.D.; Houweling, Z.S.; Li, H. B. T.; Rath, J.K.; Schuttauf, J.A.; Stolk, R.L.; Verlaan, V.; van der Werf, C.H.M.

    2008-01-01

    We present recent progress on hot-wire deposited thin film solar cells and applications of silicon nitride. The cell efficiency reached for μc-Si:H n–i–p solar cells on textured Ag/ZnO presently is 8.5%, in line with the state-of-the-art level for μc-Si:H n–i–p's for any method of deposition. Such

  2. Hot-Wire Chemical Vapor Deposition Of Polycrystalline Silicon : From Gas Molecule To Solar Cell

    Science.gov (United States)

    van Veenendaal, P. A. T. T.

    2002-10-01

    Although the effort to investigate the use of renewable energy sources, such as wind and solar energy, has increased, their contribution to the total energy consumption remains insignificant. The conversion of solar energy into electricity through solar cells is one of the most promising techniques, but the use of these cells is limited by the high cost of electricity. The major contributions to these costs are the material and manufacturing costs. Over the past decades, the development of silicon based thin film solar cells has received much attention, because the fabrication costs are low. A promising material for use in thin film solar cells is polycrystalline silicon (poly-Si:H). A relatively new technique to deposit poly-Si:H is Hot-Wire Chemical Vapor Deposition (Hot-Wire CVD), in which the reactant gases are catalytically decomposed at the surface of a hot filament, mainly tungsten and tantalum. The main advantages of Hot-Wire CVD over PE-CVD are absence of ion bombardment, high deposition rate, low equipment cost and high gas utilization. This thesis deals with the full spectrum of deposition, characterization and application of poly-Si:H thin films, i.e. from gas molecule to solar cell. Studies on the decomposition of silane on the filament showed that the process is catalytic of nature and that silane is decomposed into Si and 4H. The dominant gas phase reaction is the reaction of Si and H with silane, resulting in SiH3, Si2H6, Si3H6 and H2SiSiH2. The film growth precursors are Si, SiH3 and Si2H4. Also, XPS results on used tantalum and tungsten filaments are discussed. The position dependent measurements show larger silicon contents at the ends of the tungsten filament, as compared to the middle, due to a lower filament temperature. This effect is insignificant for a tantalum filament. Deposition time dependent measurements show an increase in silicon content of the tungsten filament with time, while the silicon content on the tantalum filament saturates

  3. Heat transfer monitoring by means of the hot wire technique and finite element analysis software.

    Science.gov (United States)

    Hernández Wong, J; Suarez, V; Guarachi, J; Calderón, A; Rojas-Trigos, J B; Juárez, A G; Marín, E

    2014-01-01

    It is reported the study of the radial heat transfer in a homogeneous and isotropic substance with a heat linear source in its axial axis. For this purpose, the hot wire characterization technique has been used, in order to obtain the temperature distribution as a function of radial distance from the axial axis and time exposure. Also, the solution of the transient heat transport equation for this problem was obtained under appropriate boundary conditions, by means of finite element technique. A comparison between experimental, conventional theoretical model and numerical simulated results is done to demonstrate the utility of the finite element analysis simulation methodology in the investigation of the thermal response of substances. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Landing Gear Components Noise Study - PIV and Hot-Wire Measurements

    Science.gov (United States)

    Hutcheson, Florence V.; Burley, Casey L.; Stead, Daniel J.; Becker, Lawrence E.; Price, Jennifer L.

    2010-01-01

    PIV and hot-wire measurements of the wake flow from rods and bars are presented. The test models include rods of different diameters and cross sections and a rod juxtaposed to a plate. The latter is representative of the latch door that is attached to an aircraft landing gear when the gear is deployed, while the single and multiple rod configurations tested are representative of some of the various struts and cables configuration present on an aircraft landing gear. The test set up is described and the flow measurements are presented. The effect of model surface treatment and freestream turbulence on the spanwise coherence of the vortex shedding is studied for several rod and bar configurations.

  5. Distributed image processing system for the monitoring of hot steel wire

    Science.gov (United States)

    O'Leary, Paul; Weiss, Michael; Schiller, Arnulf

    2003-05-01

    In a prototype for monitoring hot steel wire different technologies are integrated to achieve a robust, flexibly configurable and scalable imaging system. It is designed as a distributed system with private network and Tuplespace communication implementable on a LINUX Server. Intelligent cameras grab and process the image data. For real time communication between the cameras and standard industrial I/O-modules (IEC-61131) MODBUS/TCP messaging is applied. A switch with integrated firewall makes services available to the supervisory control system. Results are available as XML-logfiles. The image processing defines the upper and lower edges of the material by minimum/maximum filtering of the y-gradient. Dual Grassmanian coordinates are used to fit two parallel lines to the edge points by singular value decomposition. This gives the distance between the lines and the confidence interval of each measurement simultaneously, whereas latter is used to reject poor data. Changes of the distance are analysed computing local central moments. Presently, 12 images per second are acquired. The application is able to detect spontaneous rotation of the wire around the axis of rolling directly at the rolling stands and treats also poor images (due to steam of cooling water). It indicates resulting defects, which may go undetected otherwise.

  6. Extension of the lifetime of tantalum filaments in the hot-wire (Cat) 3 Chemical Vapor Deposition process

    CSIR Research Space (South Africa)

    Knoesen, D

    2008-01-01

    Full Text Available One of the prime components of a hot-wire (Cat) Chemical Vapor Deposition system is the filament used to pyro-catalytically crack the gases like silane. Burnt out tantalum filaments were studied to determine the possible improvement of lifetime...

  7. Design and implementation of a hot-wire probe for simultaneous velocity and vorticity vector measurements in boundary layers

    Science.gov (United States)

    Zimmerman, S.; Morrill-Winter, C.; Klewicki, J.

    2017-10-01

    A multi-sensor hot-wire probe for simultaneously measuring all three components of velocity and vorticity in boundary layers has been designed, fabricated and implemented in experiments up to large Reynolds numbers. The probe consists of eight hot-wires, compactly arranged in two pairs of orthogonal ×-wire arrays. The ×-wire sub-arrays are symmetrically configured such that the full velocity and vorticity vectors are resolved about a single central location. During its design phase, the capacity of this sensor to accurately measure each component of velocity and vorticity was first evaluated via a synthetic experiment in a set of well-resolved DNS fields. The synthetic experiments clarified probe geometry effects, allowed assessment of various processing schemes, and predicted the effects of finite wire length and wire separation on turbulence statistics. The probe was subsequently fabricated and employed in large Reynolds number experiments in the Flow Physics Facility wind tunnel at the University of New Hampshire. Comparisons of statistics from the actual probe with those from the simulated sensor exhibit very good agreement in trend, but with some differences in magnitude. These comparisons also reveal that the use of gradient information in processing the probe data can significantly improve the accuracy of the spanwise velocity measurement near the wall. To the authors' knowledge, the present are the largest Reynolds number laboratory-based measurements of all three vorticity components in boundary layers.

  8. Laser Hot Wire Process: A Novel Process for Near-Net Shape Fabrication for High-Throughput Applications

    Science.gov (United States)

    Kottman, Michael; Zhang, Shenjia; McGuffin-Cawley, James; Denney, Paul; Narayanan, Badri K.

    2015-03-01

    The laser hot wire process has gained considerable interest for additive manufacturing applications, leveraging its high deposition rate, low dilution, thermal stability, and general metallurgical control including the ability to introduce and preserve desired meta-stable phases. Recent advancements in closed-loop process control and laser technology have increased productivity, process stability, and control of deposit metallurgy. The laser hot wire process has shown success in several applications: repairing and rejuvenating casting dies, depositing a variety of alloys including abrasion wear-resistant overlays with solid and tubular wires, and producing low-dilution (<5%) nickel alloy overlays for corrosion applications. The feasibility of fabricating titanium buildups is being assessed for aerospace applications.

  9. On the possibility to grow zinc oxide-based transparent conducting oxide films by hot-wire chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Abrutis, Adulfas, E-mail: adulfas.abrutis@chf.vu.lt; Silimavicus, Laimis; Kubilius, Virgaudas; Murauskas, Tomas; Saltyte, Zita; Kuprenaite, Sabina; Plausinaitiene, Valentina [Faculty of Chemistry, Vilnius University, Naugarduko 24, LT-03225 Vilnius (Lithuania)

    2014-03-15

    Hot-wire chemical vapor deposition (HW-CVD) was applied to grow zinc oxide (ZnO)-based transparent conducting oxide (TCO) films. Indium (In)-doped ZnO films were deposited using a cold wall pulsed liquid injection CVD system with three nichrome wires installed at a distance of 2 cm from the substrate holder. The wires were heated by an AC current in the range of 0–10 A. Zn and In 2,2,6,6-tetramethyl-3,5-heptanedionates dissolved in 1,2-dimethoxyethane were used as precursors. The hot wires had a marked effect on the growth rates of ZnO, In-doped ZnO, and In{sub 2}O{sub 3} films; at a current of 6–10 A, growth rates were increased by a factor of ≈10–20 compared with those of traditional CVD at the same substrate temperature (400 °C). In-doped ZnO films with thickness of ≈150 nm deposited on sapphire-R grown at a wire current of 9 A exhibited a resistivity of ≈2 × 10{sup −3} Ωcm and transparency of >90% in the visible spectral range. These initial results reveal the potential of HW-CVD for the growth of TCOs.

  10. Developing a reliable signal wire attachment method for rail.

    Science.gov (United States)

    2014-11-01

    The goal of this project was to develop a better attachment method for rail signal wires to improve the reliability of signaling : systems. EWI conducted basic research into the failure mode of current attachment methods and developed and tested a ne...

  11. Effect of wall-mounted cylinders on a turbulent boundary layer: hot wire measurements

    Science.gov (United States)

    Ortiz-Dueñas, Cecilia; Ryan, Mitchell; Longmire, Ellen

    2010-11-01

    Wall-mounted cylinders with height-to-diameter ratio H/D = 2 and large enough to protrude into the logarithmic region, H^+= 200, are used to alter a turbulent boundary layer with Reτ=1150 in an attempt to affect the organization of the coherent vortical structures. Hot-wire measurements, including velocity profiles and frequency spectra, were acquired downstream of a single cylinder and spanwise arrays of cylinders. The single cylinder yielded a momentum deficit that extended from z^+=20 to 200, and a redistribution of the streamwise rms velocity towards the half cylinder height with a corresponding increase in the power spectral density over a broad frequency range. Cylinder arrays with 3D spanwise spacing yielded significant wake interactions. The largest mean streamwise velocity deficits and rms values occurred in the log region at mid-span between cylinders. More detail on the effect of cylinder spacing will be provided in the talk. The results suggest that turbulence within the boundary layer leads to broader spanwise interactions than those occurring in wakes of cylinder arrays in uniform cross flow.

  12. Low temperature deposition of crystalline silicon on glass by hot wire chemical vapor deposition

    Science.gov (United States)

    Chung, Yung-Bin; Park, Hyung-Ki; Lee, Dong-Kwon; Jo, Wook; Song, Jean-Ho; Lee, Sang-Hoon; Hwang, Nong-Moon

    2011-07-01

    Although the deposition of crystalline silicon on a glass substrate has been pursued using hot wire chemical vapor deposition or plasma enhanced chemical vapor deposition for applications in flat panel displays and solar cells, the process has been only partly successful because of the inevitable formation of an amorphous incubation layer on a glass substrate. Currently, the crystalline silicon films are prepared by depositing an amorphous silicon film on a glass substrate and then crystallizing it by excimer laser annealing (ELA), metal induced crystallization or rapid thermal annealing (RTA). Here we report a new process, which can remove the amorphous incubation layer and thereby deposit crystalline silicon directly on glass using HCl. The intrinsic crystalline silicon film has a conductivity of 3.7×10 -5 Scm -1 and the n-type doped crystalline silicon film has the Hall mobility of 15.8 cm 2V -1 s -1, whose values are comparable to those prepared by ELA and RTA, respectively.

  13. Employing Hot Wire Anemometry to Directly Measure the Water Balance of a Commercial Proton Exchange Membrane Fuel Cell Stack

    DEFF Research Database (Denmark)

    Shakhshir, Saher Al; Berning, Torsten

    2016-01-01

    and increased degradation rates. Clearly, a fundamental understanding of all aspects of water management in PEMFC is imperative. This includes the fuel cell water balance, i.e. which fraction of the product water leaves the fuel cell via the anode channels versus the cathode channel. Our research group...... is currently developing a novel technique to obtain an ad-hoc and real time electrical signal of the fuel cell water balance by employing hot wire anemometry. In this work, the hot wire sensor is placed in the anode outlet of a commercial air-cooled fuel cell stack by Ballard Power Systems, and the voltage......Proton exchange membrane fuel cells (PEMFC’s) are currently being commercialized for various applications ranging from automotive (e.g. the Toyota Mirai) to stationary such as powering telecom backup units. In PEMFC’s, oxygen from air is internally combined with hydrogen to form water and produce...

  14. Structural evolution of a Ta-filament during hot-wire chemical vapour deposition of Silicon investigated by electron backscatter diffraction

    CSIR Research Space (South Africa)

    Oliphant, CJ

    2012-03-01

    Full Text Available In this study we investigate the structural changes of a burnt-out tantalum filament that was operated at typical hydrogenated nanocrystalline silicon synthesis conditions in our hot-wire chemical vapour deposition chamber. Scanning electron...

  15. Analysis of pulsed wire method for field integral measurements in ...

    Indian Academy of Sciences (India)

    of the acoustic wave in the wire could be significant and our analysis provides a method for the evaluation of the magnetic field profile even in such cases taking the effect due to dispersion into account in an exact way. Keywords. Undulator; free-electron laser; synchrotron radiation source; magnetic char- acterization.

  16. Analysis of pulsed wire method for field integral measurements in ...

    Indian Academy of Sciences (India)

    In this paper, we present a theoretical analysis of this technique by finding out the analytic solution of the differential equation for the forced vibration of the wire taking dispersion due to stiffness into account. Method of images is used to extend these solutions to include reflections at the ends. For long undulators, the effect of ...

  17. Tandem solar cells deposited using hot-wire chemical vapor deposition

    Science.gov (United States)

    van Veen, M. K.

    2003-05-01

    In this thesis, the application of the hot-wire chemical vapor deposition (HWCVD) technique for the deposition of silicon thin films is described. The HWCVD technique is based on the dissociation of silicon-containing gasses at the catalytic surface of a hot filament. Advantages of this technique are the high deposition rate, the low equipment costs, and the scalability. The main goal of this thesis is the optimization of the material properties of both hydrogenated amorphous silicon and microcrystalline silicon, so that these materials can be incorporated as the absorbing layers in tandem solar cells. Firstly, the influence of specific deposition parameters on the material quality of hydrogenated amorphous silicon was investigated. With the use of tantalum filaments, the deposition temperature could be decreased to moderate temperatures, while the (electronic) properties of the amorphous silicon were improved. However, at these low filament temperatures the silicide formation at the filaments was enhanced, resulting in a decrease in the deposition rate and a deterioration of the material quality over time. For extensive silicide formation, even epitaxial growth on crystalline wafers was observed. By preheating the filaments at elevated temperature before deposition, the influence of silicide formation could be minimized, which resulted in an improvement in the reproducibility of the material quality. Solar cells, in which the absorbing layer was made at moderate temperature, had high open-circuit voltages and high fill factors. The best n-i-p structured cell on plain stainless steel had an initial efficiency of 7.2 %. The incorporation of amorphous silicon in p-i-n structured cells with a textured front contact resulted in a higher short-circuit current density and a higher efficiency. Occasionally, many n-i-p structured cells showed shunting problems. The number of working cells was directly correlated to the age of the filaments. The presence of silicides on the

  18. ROBUST hot wire probe efficiency for total water content measurements in glaciated conditions

    Science.gov (United States)

    Leroy, Delphine; Lilie, Lyle; Weber, Marc; Schwarzenboeck, Alfons; Strapp, J. Walter

    2017-04-01

    During the two High Altitude Ice Crystals (HAIC, Dezitter et al. 2013)/High Ice Water Content (HIWC, Strapp et al., 2016a) international flight campaigns that investigated deep convection in the tropics, the French Falcon 20 research aircraft was equipped with two different devices measuring the Total Water Content (TWC): - the IKP-2 (Isokinetic Probe, Davison et al. 2008, 2016), - and the hot wire ROBUST probe (Strapp et al. 2008; Grandin et al. 2014). The IKP-2 probe is an evaporator that has been specifically designed to measure high ice water content (Strapp et al. 2016b) with a collection efficiency near unity. It has undergone extensive performance assessment in liquid and glaciated conditions in several wind tunnels. The Robust probe was initially developed by Science Engineering Associates to estimate high ice water content in a high speed wind tunnel, in harsh conditions where other hot-wires had been observed to suffer failures. It was known at the outset that, like other hot-wire TWC probes, it would measure only a quasi-constant fraction of the true ice water content. Early wind tunnel and flight experience with the ROBUST probe revealed that this fraction was the order of 40% for ice crystals. During the HAIC/HIWC campaigns (Leroy et al. 2016, 2017), supercooled liquid water conditions were documented according to a detailed analysis of a Rosemount Ice detector (RICE) and a Cloud Droplet Probe (CDP) measurements, and were found to be rare. Thus, the HAIC/HIWC dataset represents a unique opportunity to study in more detail the ROBUST efficiency in glaciated conditions, using the IKP-2 values as a comparative reference. Comparison of IKP-2 and ROBUST measurements will show that the ROBUST behavior differs between low (below 1.5 g/m3) and high (above 2 g/m3) ice content conditions and is also sensitive to temperature. The sensitivity of the ROBUST collection efficiency to ice particles size could also be explored as optical imaging probes were part of the

  19. Laser brazing of a steel/aluminium assembly with hot filler wire (88% Al, 12% Si)

    Energy Technology Data Exchange (ETDEWEB)

    Mathieu, Alexandre [Laboratoire Laser et Traitement des Materiaux (LTm), IUT Le Creusot, 12 rue de la Fonderie, 71200 Le Creusot (France)]. E-mail: a.mathieu@iutlecreusot.u-bourgogne.fr; Pontevicci, Sebastien [Laboratoire Multi-materiaux et Interfaces (LMI), Universite Claude Bernard, Lyon 1, 69622 Villeurbanne (France); Viala, Jean-claude [Laboratoire Multi-materiaux et Interfaces (LMI), Universite Claude Bernard, Lyon 1, 69622 Villeurbanne (France); Cicala, Eugen [Laboratoire Laser et Traitement des Materiaux (LTm), IUT Le Creusot, 12 rue de la Fonderie, 71200 Le Creusot (France); Universitatea ' Politehnica' din Timisoara, P-ta Victoriei, nr.2, 300222 Timisoara (Romania); Mattei, Simone [Laboratoire Laser et Traitement des Materiaux (LTm), IUT Le Creusot, 12 rue de la Fonderie, 71200 Le Creusot (France); Grevey, Dominique [Laboratoire Laser et Traitement des Materiaux (LTm), IUT Le Creusot, 12 rue de la Fonderie, 71200 Le Creusot (France)

    2006-11-05

    The main problem in joining steel to aluminium by a thermal process (e.g. TIG, MIG) is the formation of brittle intermetallic phases, that causes the mechanical performance of the assembly to be poor. A laser beam, however, can localize the fusion and inhibit the formation of these phases. This article presents a feasibility study for steel/aluminium assemblies with filler wire of 88% Al and 12% Si. Analysis of the resultant joints may show the causes of fracture. An experimental design study is conducted, to see how the mechanical performance of such joints could be improved. This method establishes what the best operational limits are and shows how different operational conditions influence the various ways in which fractures occur.

  20. A hot-wire probe for thermal measurements of nanowires and nanotubes inside a transmission electron microscope.

    Science.gov (United States)

    Dames, C; Chen, S; Harris, C T; Huang, J Y; Ren, Z F; Dresselhaus, M S; Chen, G

    2007-10-01

    A hot wire probe has been developed for use inside a transmission electron microscope to measure the thermal resistance of individual nanowires, nanotubes, and their contacts. No microfabrication is involved. The probe is made from a platinum Wollaston wire and is pretensioned to minimize the effects of thermal expansion, intrinsic thermal vibrations, and Lorentz forces. An in situ nanomanipulator is used to select a particular nanowire or nanotube for measurement, and contacts are made with liquid metal droplets or by electron-beam induced deposition. Detailed thermal analysis shows that for best sensitivity, the thermal resistance of the hot-wire probe should be four times that of the sample, but a mismatch of more than two orders of magnitude may be acceptable. Data analysis using the ratio of two ac signals reduces the experimental uncertainty. The range of detectable sample thermal resistances spans from approximately 10(3) to 10(9) KW. The probe can also be adapted for measurements of the electrical conductance and Seebeck coefficient of the same sample. The probe was used to study a multiwalled carbon nanotube with liquid Ga contacts. The measured thermal resistance of 3.3 x 10(7) KW had a noise level of approximately +/-3% and was repeatable to within +/-10% upon breaking and re-making the contact.

  1. Hot wire chemical vapor deposition chemistry in the gas phase and on the catalyst surface with organosilicon compounds.

    Science.gov (United States)

    Shi, Yujun

    2015-02-17

    CONSPECTUS: Hot wire chemical vapor deposition (HWCVD), also referred to as catalytic CVD (Cat-CVD), has been used to produce Si-containing thin films, nanomaterials, and functional polymer coatings that have found wide applications in microelectronic and photovoltaic devices, in automobiles, and in biotechnology. The success of HWCVD is largely due to its various advantages, including high deposition rate, low substrate temperatures, lack of plasma-induced damage, and large-area uniformity. Film growth in HWCVD is induced by reactive species generated from primary decomposition on the metal wire or from secondary reactions in the gas phase. In order to achieve a rational and efficient optimization of the process, it is essential to identify the reactive species and to understand the chemical kinetics that govern the production of these precursor species for film growth. In this Account, we report recent progress in unraveling the complex gas-phase reaction chemistry in the HWCVD growth of silicon carbide thin films using organosilicon compounds as single-source precursors. We have demonstrated that laser ionization mass spectrometry is a powerful diagnostic tool for studying the gas-phase reaction chemistry when combined with the methods of isotope labeling and chemical trapping. The four methyl-substituted silane molecules, belonging to open-chain alkylsilanes, dissociatively adsorb on W and Ta filaments to produce methyl radical and H2 molecule. Under the typical deposition pressures, with increasing number of methyl substitution, the dominant chemistry occurring in the gas phase switches from silylene/silene reactions to free-radical short chain reactions. This change in dominant reaction intermediates from silylene/silene to methyl radicals explains the observation from thin film deposition that silicon carbide films become more C-rich with a decreasing number of Si-H bonds in the four precursor molecules. In the case of cyclic monosilacyclobutanes, we have

  2. Mechanical properties and aesthetics of FRP orthodontic wire fabricated by hot drawing.

    Science.gov (United States)

    Imai, T; Watari, F; Yamagata, S; Kobayashi, M; Nagayama, K; Toyoizumi, Y; Nakamura, S

    1998-12-01

    The FRP wires 0.5 mm in diameter with a multiple fiber structure were fabricated by drawing the fiber polymer complex at 250 degrees C for an esthetic, transparent orthodontic wire. Biocompatible CaO-P2O5-SiO2-Al2O3 (CPSA) glass fibers of 8-20 microm in diameter were oriented unidirectionally in the longitudinal direction in PMMA matrix. The mechanical properties were investigated by 3-point flexural test. The FRP wire showed sufficient strength and a very good elastic recovery after deformation. Young's modulus and the flexural load at deflection 1 mm were nearly independent of the fiber diameter and linearly increased with the fiber fraction. The dependence on fiber fraction obeys well the rule of mixture. This FRP wire could cover the range of strength corresponding to the conventional metal orthodontic wires from Ni-Ti used in the initial stage of orthodontic treatments to Co-Cr used in the final stage by changing the volume ratio of glass fibers with the same external diameter. The estheticity in external appearance was excellent. Thus the new FRP wire can satisfy both mechanical properties necessary for an orthodontic wire and enough estheticity, which was not possible for the conventional metal wire.

  3. Acquisition of Turbulence Data Using the DST Group Constant-Temperature Hot-Wire Anemometer System

    Science.gov (United States)

    2015-10-01

    leads form one arm of a Wheatstone bridge . The wire, which is heated by passing an electric current through it, has a high frequency response and is...to keep the Wheatstone bridge balanced, so that the wire has a constant resistance and hence constant temperature. An offset voltage is applied to...when the wire is operating will be (6 x 2) + 0.7, i.e. 12.7 Ω. To balance the Wheatstone bridge , it is necessary to adjust balance resistors in

  4. Employing Hot Wire Anemometry to Directly Measure the Water Balance of a Proton Exchange Membrane Fuel Cell

    DEFF Research Database (Denmark)

    Shakhshir, Saher Al; Berning, Torsten

    Proton exchange membrane fuel cells (PEMFC’s) are currently being commercialized for various applications ranging from automotive to stationary such as powering telecom back-up units. In PEMFC’s, oxygen from air is internally combined with hydrogen to form water and produce electricity and waste...... in hot wire anemometry is the description of the Nusselt number as function of the Reynolds number and the Prandtl number, and in the current application it can be shown it is essential to employ a power-law equation instead of the commonly employed Churchill Bernstein equation. It will be shown...

  5. Sliding bubbles on a hot horizontal wire in a subcooled bath

    Science.gov (United States)

    Duchesne, Alexis; Dubois, Charles; Caps, Hervé

    2015-11-01

    When a wire is heated up to the boiling point in a liquid bath some bubbles will nucleate on the wire surface. Traditional nucleate boiling theory predicts that bubbles generate from active nucleate site, grow up and depart from the heating surface due to buoyancy and inertia. However, an alternative scenario is presented in the literature for a subcooled bath: bubbles slide along the horizontal wire before departing. New experiments were performed by using a constantan wire and different liquids, varying the injected power. Silicone oil, water and even liquid nitrogen were tested in order to vary wetting conditions, liquid viscosities and surface tensions. We explored the influence of the wire diameter and of the subcooled bath temperature. We observed, of course, sliding motion, but also a wide range of behaviors from bubbles clustering to film boiling. We noticed that bubbles could change moving sense, especially when encountering with another bubble. The bubble speed is carefully measured and can reach more than 100 mm/s for a millimetric bubble. We investigated the dependence of the speed on the different parameters and found that this speed is, for a given configuration, quite independent of the injected power. We understand these phenomena in terms of Marangoni effects. This project has been financially supported by ARC SuperCool contract of the University of Liège.

  6. Numerical and experimental determination of the minimum and maximum measuring times for the hot wire parallel technique

    Directory of Open Access Journals (Sweden)

    Santos W. N. dos

    2003-01-01

    Full Text Available The hot wire technique is considered to be an effective and accurate means of determining the thermal conductivity of ceramic materials. However, specifically for materials of high thermal diffusivity, the appropriate time interval to be considered in calculations is a decisive factor for getting accurate and consistent results. In this work, a numerical simulation model is proposed with the aim of determining the minimum and maximum measuring time for the hot wire parallel technique. The temperature profile generated by this model is in excellent agreement with that one experimentally obtained by this technique, where thermal conductivity, thermal diffusivity and specific heat are simultaneously determined from the same experimental temperature transient. Eighteen different specimens of refractory materials and polymers, with thermal diffusivities ranging from 1x10-7 to 70x10-7 m²/s, in shape of rectangular parallelepipeds, and with different dimensions were employed in the experimental programme. An empirical equation relating minimum and maximum measuring times and the thermal diffusivity of the sample is also obtained.

  7. Hot-wire air flow meter for gasoline fuel-injection system. Calculation of air mass in cylinder during transient condition; Gasoline funsha system yo no netsusenshiki kuki ryuryokei. Kato untenji no cylinder juten kukiryo no keisan

    Energy Technology Data Exchange (ETDEWEB)

    Oyama, Y. [Hitachi Car Engineering, Ltd., Tokyo (Japan); Nishimura, Y.; Osuga, M.; Yamauchi, T. [Hitachi, Ltd., Tokyo (Japan)

    1997-10-01

    Air flow characteristics of hot-wire air flow meters for gasoline fuel-injection systems with supercharging and exhaust gas recycle during transient conditions were investigated to analyze a simple method for calculating air mass in cylinder. It was clarified that the air mass in cylinder could be calculated by compensating for the change of air mass in intake system by using aerodynamic models of intake system. 3 refs., 6 figs., 1 tab.

  8. Highly Sensitive Hot-Wire Anemometry Based on Macro-Sized Double-Walled Carbon Nanotube Strands.

    Science.gov (United States)

    Wang, Dingqu; Xiong, Wei; Zhou, Zhaoying; Zhu, Rong; Yang, Xing; Li, Weihua; Jiang, Yueyuan; Zhang, Yajun

    2017-08-01

    This paper presents a highly sensitive flow-rate sensor with carbon nanotubes (CNTs) as sensing elements. The sensor uses micro-size centimeters long double-walled CNT (DWCNT) strands as hot-wires to sense fluid velocity. In the theoretical analysis, the sensitivity of the sensor is demonstrated to be positively related to the ratio of its surface. We assemble the flow sensor by suspending the DWCNT strand directly on two tungsten prongs and dripping a small amount of silver glue onto each contact between the DWCNT and the prongs. The DWCNT exhibits a positive TCR of 1980 ppm/K. The self-heating effect on the DWCNT was observed while constant current was applied between the two prongs. This sensor can evidently respond to flow rate, and requires only several milliwatts to operate. We have, thus far, demonstrated that the CNT-based flow sensor has better sensitivity than the Pt-coated DWCNT sensor.

  9. Filler wire for aluminum alloys and method of welding

    Science.gov (United States)

    Bjorkman, Jr., Gerald W. O. (Inventor); Cho, Alex (Inventor); Russell, Carolyn K. (Inventor)

    2003-01-01

    A weld filler wire chemistry has been developed for fusion welding 2195 aluminum-lithium. The weld filler wire chemistry is an aluminum-copper based alloy containing high additions of titanium and zirconium. The additions of titanium and zirconium reduce the crack susceptibility of aluminum alloy welds while producing good weld mechanical properties. The addition of silver further improves the weld properties of the weld filler wire. The reduced weld crack susceptibility enhances the repair weldability, including when planishing is required.

  10. The anchors of steel wire ropes, testing methods and their results

    Directory of Open Access Journals (Sweden)

    J. Krešák

    2012-10-01

    Full Text Available The present paper introduces an application of the acoustic and thermographic method in the defectoscopic testing of immobile steel wire ropes at the most critical point, the anchor. First measurements and their results by these new defectoscopic methods are shown. In defectoscopic tests at the anchor, the widely used magnetic method gives unreliable results, and therefore presents a problem for steel wire defectoscopy. Application of the two new methods in the steel wire defectoscopy at the anchor point will enable increased safety measures at the anchor of steel wire ropes in bridge, roof, tower and aerial cable lift constructions.

  11. Bubble reconstruction method for wire-mesh sensors measurements

    Science.gov (United States)

    Mukin, Roman V.

    2016-08-01

    A new algorithm is presented for post-processing of void fraction measurements with wire-mesh sensors, particularly for identifying and reconstructing bubble surfaces in a two-phase flow. This method is a combination of the bubble recognition algorithm presented in Prasser (Nuclear Eng Des 237(15):1608, 2007) and Poisson surface reconstruction algorithm developed in Kazhdan et al. (Poisson surface reconstruction. In: Proceedings of the fourth eurographics symposium on geometry processing 7, 2006). To verify the proposed technique, a comparison was done of the reconstructed individual bubble shapes with those obtained numerically in Sato and Ničeno (Int J Numer Methods Fluids 70(4):441, 2012). Using the difference between reconstructed and referenced bubble shapes, the accuracy of the proposed algorithm was estimated. At the next step, the algorithm was applied to void fraction measurements performed in Ylönen (High-resolution flow structure measurements in a rod bundle (Diss., Eidgenössische Technische Hochschule ETH Zürich, Nr. 20961, 2013) by means of wire-mesh sensors in a rod bundle geometry. The reconstructed bubble shape yields bubble surface area and volume, hence its Sauter diameter d_{32} as well. Sauter diameter is proved to be more suitable for bubbles size characterization compared to volumetric diameter d_{30}, proved capable to capture the bi-disperse bubble size distribution in the flow. The effect of a spacer grid was studied as well: For the given spacer grid and considered flow rates, bubble size frequency distribution is obtained almost at the same position for all cases, approximately at d_{32} = 3.5 mm. This finding can be related to the specific geometry of the spacer grid or the air injection device applied in the experiments, or even to more fundamental properties of the bubble breakup and coagulation processes. In addition, an application of the new algorithm for reconstruction of a large air-water interface in a tube bundle is

  12. Applying hot wire anemometry to directly measure the water balance in a proton exchange membrane fuel cell - Part 1

    DEFF Research Database (Denmark)

    Berning, Torsten; Al Shakhshir, Saher

    2015-01-01

    In order to accurately determine the water balance of a proton exchange membrane fuel cell it has recently been suggested to employ constant temperature anemometry (CTA), a frequently used method to measure the velocity of a fluid stream. CTA relies on convective heat transfer around a heated wire...... the equations required to calculate the heat transfer coefficient and the resulting voltage signal as function of the fuel cell water balance. The most critical and least understood part is the determination of the Nusselt number to calculate the heat transfer between the wire and the gas stream. Different...... for all current densities. Therefore, only one curve-fit equation will be required. The voltage curve E0 is an arbitrary calibration curve, and this can be conveniently chosen to be the voltage signal for a dry hydrogen stream at a given temperature and various flow rates which can be easily measured....

  13. Evaluation of mechanical properties of steel wire ropes by statistical methods

    Directory of Open Access Journals (Sweden)

    Boroška Ján

    1999-12-01

    Full Text Available The contribution deals with the evaluation of mechanical properties of steel wire ropes using statistical methods from the viewpoint of the quality of single wires as well as the internal construction of the wire ropes. The evaluation is based on the loading capacity calculated from the strength, number of folds and torsions. For the better ilustration, a box plot has been constructed.

  14. Microwave Wire Interrogation Method Mapping Pressure under High Temperatures

    Directory of Open Access Journals (Sweden)

    Xiaoyong Chen

    2017-12-01

    Full Text Available It is widely accepted that wireless reading for in-situ mapping of pressure under high-temperature environments is the most feasible method, because it is not subject to frequent heterogeneous jointing failures and electrical conduction deteriorating, or even disappearing, under heat load. However, in this article, we successfully demonstrate an in-situ pressure sensor with wire interrogation for high-temperature applications. In this proof-of-concept study of the pressure sensor, we used a microwave resonator as a pressure-sensing component and a microwave transmission line as a pressure characteristic interrogation tunnel. In the sensor, the line and resonator are processed into a monolith, avoiding a heterogeneous jointing failure; further, microwave signal transmission does not depend on electrical conduction, and consequently, the sensor does not suffer from the heat load. We achieve pressure monitoring under 400 °C when employing the sensor simultaneously. Our sensor avoids restrictions that exist in wireless pressure interrogations, such as environmental noise and interference, signal leakage and security, low transfer efficiency, and so on.

  15. The Laser Welding with Hot Wire of 316LN Thick Plate Applied on ITER Correction Coil Case

    CERN Document Server

    Fang, Chao; Wu, Weiyue; Wei, Jing; Zhang, Shuquan; Li, Hongwei; Dolgetta, N; Libeyre, P; Cormany, C; Sgobba, S

    2014-01-01

    ITER correction coil (CC) cases have characteristics of small cross section, large dimensions, and complex structure. The cases are made of heavy thick (20 mm), high strength and high toughness austenitic stainless steel 316LN. The multi-pass laser welding with hot wire technology is used for the case closure welding, due to its low heat input and deformation. In order to evaluate the reliability of this welding technology, 20 mm welding samples with the same groove structure and welding depth as the cases were welded. High purity argon was used as the shielding gas to prevent oxidation because of the narrowness and depth of the weld. In this paper investigation of, microstructure characteristics and mechanical properties of welded joints using optimized welding parameters are presented. The results show that the base metal, fusion metal, and heat affected zone (HAZ) are all have fully austenitic microstructure, and that the grain size of fusion metal was finer than that of the base metal. The welding resulte...

  16. Thermal conductivity of amorphous and nanocrystalline silicon films prepared by hot-wire chemical-vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Jugdersuren, B.; Kearney, B. T.; Queen, D. R.; Metcalf, T. H.; Culbertson, J. C.; Chervin, C. N.; Stroud, R. M.; Nemeth, W.; Wang, Q.; Liu, Xiao

    2017-07-01

    We report 3..omega.. thermal conductivity measurements of amorphous and nanocrystalline silicon thin films from 85 to 300 K prepared by hot-wire chemical-vapor deposition, where the crystallinity of the films is controlled by the hydrogen dilution during growth. The thermal conductivity of the amorphous silicon film is in agreement with several previous reports of amorphous silicon prepared by a variety of deposition techniques. The thermal conductivity of the as-grown nanocrystalline silicon film is 70% higher and increases 35% more after an anneal at 600 degrees C. They all have similarly weak temperature dependence. Structural analysis shows that the as-grown nanocrystalline silicon is approximately 60% crystalline, nanograins and grain boundaries included. The nanograins, averaging 9.1 nm in diameter in the as-grown film, are embedded in an amorphous matrix. The grain size increases to 9.7 nm upon annealing, accompanied by the disappearance of the amorphous phase. We extend the models of grain boundary scattering of phonons with two different non-Debye dispersion relations to explain our result of nanocrystalline silicon, confirming the strong grain size dependence of heat transport for nanocrystalline materials. However, the similarity in thermal conductivity between amorphous and nanocrystalline silicon suggests the heat transport mechanisms in both structures may not be as dissimilar as we currently understand.

  17. Applying hot-wire anemometry to directly measure the water balance in a proton exchange membrane fuel cell for a pre-humidified hydrogen stream

    DEFF Research Database (Denmark)

    Berning, Torsten; Shakhshir, Saher Al

    2016-01-01

    In a recent publication it has been shown how the water balance in a proton exchange membrane fuel cell can be determined employing hot wire anemometry. The hot wire sensor has to be placed into the anode outlet pipe of the operating fuel cell, and the voltage signal E that is read from the sensor....... Finally, it will be shown how previously developed dew point diagrams for the anode side in a fuel cell can be corrected for a humidified hydrogen inlet stream....... has to be divided by a pre-determined voltage signal E0 that has been obtained for a stream of dry hydrogen where the molar flow rate corresponds to a total current I of the fuel cell stack and a stoichiometric flow ratio, ξ. Because the last two properties are usually continuously known in fuel cell...

  18. Improvement of the efficiency of triple junction n–i–p solar cells with hot-wire CVD proto- and microcrystalline silicon absorber layers

    NARCIS (Netherlands)

    Stolk, R.L.; Li, H. B. T.; Franken, R.H.; Schuttauf, J.A.; van der Werf, C.H.M.; Rath, J.K.; Schropp, R.E.I.

    2008-01-01

    Hot-wire chemical vapour deposition (HWCVD) was applied for the deposition of intrinsic protocrystalline (proto-Si:H) and microcrystalline silicon (μc-Si:H) absorber layers in thin film solar cells. For a single junction μc-Si:H n–i–p cell on a Ag/ZnO textured back reflector (TBR) with a 2.0 μm

  19. Transient Analysis of Lumped Circuit Networks Loaded Thin Wires By DGTD Method

    KAUST Repository

    Li, Ping

    2016-03-31

    With the purpose of avoiding very fine mesh cells in the proximity of a thin wire, the modified telegrapher’s equations (MTEs) are employed to describe the thin wire voltage and current distributions, which consequently results in reduced number of unknowns and augmented Courant-Friedrichs-Lewy (CFL) number. As hyperbolic systems, both the MTEs and the Maxwell’s equations are solved by the discontinuous Galerkin time-domain (DGTD) method. In realistic situations, the thin wires could be either driven or loaded by circuit networks. The thin wire-circuit interface performs as a boundary condition for the thin wire solver, where the thin wire voltage and current used for the incoming flux evaluation involved in the DGTD analyzed MTEs are not available. To obtain this voltage and current, an auxiliary current flowing through the thin wire-circuit interface is introduced at each interface. Corresponding auxiliary equations derived from the invariable property of characteristic variable for hyperbolic systems are developed and solved together with the circuit equations established by the modified nodal analysis (MNA) modality. Furthermore, in order to characterize the field and thin wire interactions, a weighted electric field and a volume current density are added into the MTEs and Maxwell-Ampere’s law equation, respectively. To validate the proposed algorithm, three representative examples are presented.

  20. Impact of microcrystalline silicon carbide growth using hot-wire chemical vapor deposition on crystalline silicon surface passivation

    Energy Technology Data Exchange (ETDEWEB)

    Pomaska, M., E-mail: m.pomaksa@fz-juelich.de [Forschungszentrum Jülich, IEK5-Photovoltaics, Wilhelm-Johnen-Strasse, 52425 Jülich (Germany); Beyer, W. [Helmholtz-Zentrum Berlin für Materialien und Energie, Silicon Photovoltaics, Kekuléstrasse 5, 12489 Berlin (Germany); Neumann, E. [Forschungszentrum Jülich, PGI-8-PT, Wilhelm-Johnen-Strasse, 52425 Jülich (Germany); Finger, F.; Ding, K. [Forschungszentrum Jülich, IEK5-Photovoltaics, Wilhelm-Johnen-Strasse, 52425 Jülich (Germany)

    2015-11-30

    Highly crystalline microcrystalline silicon carbide (μc-SiC:H) with excellent optoelectronic material properties is a promising candidate as highly transparent doped layer in silicon heterojunction (SHJ) solar cells. These high quality materials are usually produced using hot wire chemical vapor deposition under aggressive growth conditions giving rise to the removal of the underlying passivation layer and thus the deterioration of the crystalline silicon (c-Si) surface passivation. In this work, we introduced the n-type μc-SiC:H/n-type μc-SiO{sub x}:H/intrinsic a-SiO{sub x}:H stack as a front layer configuration for p-type SHJ solar cells with the μc-SiO{sub x}:H layer acting as an etch-resistant layer against the reactive deposition conditions during the μc-SiC:H growth. We observed that the unfavorable expansion of micro-voids at the c-Si interface due to the in-diffusion of hydrogen atoms through the layer stack might be responsible for the deterioration of surface passivation. Excellent lifetime values were achieved under deposition conditions which are needed to grow high quality μc-SiC:H layers for SHJ solar cells. - Highlights: • High surface passivation quality was preserved after μc-SiC:H deposition. • μc-SiC:H/μc-SiO{sub x}:H/a-SiO{sub x}:H stack a promising front layer configuration • Void expansion at a-SiO{sub x}:H/c-Si interface for deteriorated surface passivation • μc-SiC:H provides a high transparency and electrical conductivity.

  1. Method for wiring allocation and switch configuration in a multiprocessor environment

    Science.gov (United States)

    Aridor, Yariv [Zichron Ya'akov, IL; Domany, Tamar [Kiryat Tivon, IL; Frachtenberg, Eitan [Jerusalem, IL; Gal, Yoav [Haifa, IL; Shmueli, Edi [Haifa, IL; Stockmeyer, legal representative, Robert E.; Stockmeyer, Larry Joseph [San Jose, CA

    2008-07-15

    A method for wiring allocation and switch configuration in a multiprocessor computer, the method including employing depth-first tree traversal to determine a plurality of paths among a plurality of processing elements allocated to a job along a plurality of switches and wires in a plurality of D-lines, and selecting one of the paths in accordance with at least one selection criterion.

  2. Models and methods for hot spot safety work

    DEFF Research Database (Denmark)

    Vistisen, Dorte

    2002-01-01

    is the task of improving road safety through alterations of the geometrical and environmental characteristics of the existing road network. The presently applied models and methods in hot spot safety work on the Danish road network were developed about two decades ago, when data was more limited and software...... and statistical methods less developed. The purpose of this thesis is to contribute to improving "State of the art" in Denmark. Basis for the systematic hot spot safety work are the models describing the variation in accident counts on the road network. In the thesis hierarchical models disaggregated on time......Despite the fact that millions DKK each year are spent on improving roadsafety in Denmark, funds for traffic safety are limited. It is therefore vital to spend the resources as effectively as possible. This thesis is concerned with the area of traffic safety denoted "hot spot safety work", which...

  3. New devices for flow measurements: Hot film and burial wire sensors, infrared imagery, liquid crystal, and piezo-electric model

    Science.gov (United States)

    Mcree, Griffith J., Jr.; Roberts, A. Sidney, Jr.

    1991-01-01

    An experimental program aimed at identifying areas in low speed aerodynamic research where infrared imaging systems can make significant contributions is discussed. Implementing a new technique, a long electrically heated wire was placed across a laminar flow. By measuring the temperature distribution along the wire with the IR imaging camera, the flow behavior was identified.

  4. Fiducialization of the small-aperture quadrupoles based on the vibrating wire method

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Baichuan, E-mail: wangbaichuan@nint.ac.cn [State Key Laboratory of Intense Pulsed Radiation Simulation and Effect (Northwest Institute of Nuclear Technology), Xi' an 710024 (China); Tsinghua University, Beijing 100084 (China); Zheng, Shuxin, E-mail: zhengsx@tsinghua.edu.cn [Tsinghua University, Beijing 100084 (China); Wu, Lin; Du, Changtong; Xing, Qingzi [Tsinghua University, Beijing 100084 (China); Wang, Zhongming; Qiu, Mengtong [State Key Laboratory of Intense Pulsed Radiation Simulation and Effect (Northwest Institute of Nuclear Technology), Xi' an 710024 (China); Wang, Xuewu [Tsinghua University, Beijing 100084 (China)

    2016-03-11

    A fiducialization method based on vibrating wire is described dedicated to the problem of locating the magnetic center relative to external fiducials for the small-aperture quadrupoles. The advantage of this method is that the measurement of the wire position, which may be the main error source, is no longer needed. The position of the magnetic center can be directly obtained by measuring the position shift of the magnet fiducials. This method has been validated on small Permanent Magnet Quadrupoles (PMQs). Experiments have confirmed its feasibility of measuring PMQs with good repeatability of about 10 μm, and shown its high sensitivity as well as convenience.

  5. An Interactive Method Based on the Live Wire for Segmentation of the Breast in Mammography Images

    Directory of Open Access Journals (Sweden)

    Zhang Zewei

    2014-01-01

    Full Text Available In order to improve accuracy of computer-aided diagnosis of breast lumps, the authors introduce an improved interactive segmentation method based on Live Wire. This paper presents the Gabor filters and FCM clustering algorithm is introduced to the Live Wire cost function definition. According to the image FCM analysis for image edge enhancement, we eliminate the interference of weak edge and access external features clear segmentation results of breast lumps through improving Live Wire on two cases of breast segmentation data. Compared with the traditional method of image segmentation, experimental results show that the method achieves more accurate segmentation of breast lumps and provides more accurate objective basis on quantitative and qualitative analysis of breast lumps.

  6. A micro-scale hot wire anemometer based on low stress (Ni/W) multi-layers deposited on nano-crystalline diamond for air flow sensing

    Science.gov (United States)

    Talbi, A.; Gimeno, L.; Gerbedoen, J.-C.; Viard, R.; Soltani, A.; Mortet, V.; Preobrazhensky, V.; Merlen, A.; Pernod, P.

    2015-12-01

    A linear array of microscale thermal anemometers has been designed, fabricated and characterized. The sensitive element consists of a self-compensated-stress multilayer (Ni/W) patterned to form a wire with length, width, and thickness close to 200 μm, 5 μm and 2 μm respectively. The wire is deposited and supported by prongs made of nano-crystalline diamond (NCD) of about 2 μm in thickness. Due to its high Young’s modulus, NCD allows a very high mechanical toughness without the need for thicker support for the hot wire. Also, depending on grain size, the NCD is able to present thermal conductivity smaller than 10 W mK-1, providing good thermal insulation from the substrate and less conductive end losses to the prongs. The sensor was characterized experimentally. Its electrical and thermal properties were obtained first in the absence of fluid flow. The results confirm the effectiveness of thermal insulation and the mechanical robustness of the structure. The fluidic characterizations were performed and analysed in the case of an airflow with velocities of up to 30 m s-1.

  7. Hard X-ray nanoimaging method using local diffraction from metal wire

    Energy Technology Data Exchange (ETDEWEB)

    Takano, Hidekazu, E-mail: htakano@sci.u-hyogo.ac.jp; Konishi, Shigeki; Shimomura, Sho; Azuma, Hiroaki; Tsusaka, Yoshiyuki; Kagoshima, Yasushi [Center for Novel Material Science under Multi-Extreme Conditions, Graduate School of Material Science, University of Hyogo, Kamigori, Hyogo 678-1297 (Japan)

    2014-01-13

    A simple hard X-ray imaging method achieving a high spatial resolution is proposed. Images are obtained by scanning a metal wire through the wave field to be measured and rotating the sample to collect data for back projection calculations; the local diffraction occurring at the edges of the metal wire operates as a narrow line probe. In-line holograms of a test sample were obtained with a spatial resolution of better than 100 nm. The potential high spatial resolution of this method is shown by calculations using diffraction theory.

  8. A portable borehole temperature logging system using the four-wire resistance method

    Science.gov (United States)

    Erkan, Kamil; Akkoyunlu, Bülent; Balkan, Elif; Tayanç, Mete

    2017-12-01

    High-quality temperature–depth information from boreholes with a depth of 100 m or more is used in geothermal studies and in studies of climate change. Electrical wireline tools with thermistor sensors are capable of measuring borehole temperatures with millikelvin resolution. The use of a surface readout mode allows analysis of the thermally conductive state of a borehole, which is especially important for climatic and regional heat flow studies. In this study we describe the design of a portable temperature logging tool that uses the four-wire resistance measurement method. The four-wire method enables the elimination of cable resistance effects, thus allowing millikelvin resolution of temperature data at depth. A preliminary two-wire model of the system is also described. The portability of the tool enables one to collect data from boreholes down to 300 m, even in locations with limited accessibility.

  9. Static and free vibration analysis of carbon nano wires based on Timoshenko beam theory using differential quadrature method

    Directory of Open Access Journals (Sweden)

    Maziar Janghorban

    Full Text Available Static and free vibration analysis of carbon nano wires with rectangular cross section based on Timoshenko beam theory is studied in this research. Differential quadrature method (DQM is employed to solve the governing equations. From the knowledge of author, it is the first time that free vibration of nano wires is investigated. It is also the first time that differential quadrature method is used for bending analysis of nano wires.

  10. Hot-spot detection and calibration of a scanning thermal probe with a noise thermometry gold wire sample

    NARCIS (Netherlands)

    Gaitas, A.; Wolgast, S.; Covington, E.; Kurdak, C.

    2013-01-01

    Measuring the temperature profile of a nanoscale sample using scanning thermal microscopy is challenging due to a scanning probe's non-uniform heating. In order to address this challenge, we have developed a calibration sample consisting of a 1-?m wide gold wire, which can be heated electrically by

  11. Inductive method to measure very small joint resistances of superconducting wires

    CERN Document Server

    Herzog, R

    1998-01-01

    In the Large Hadron Collider (LHC), which is currently being developed at CERN, about 50,000 connections of superconducting wire will be necessary to implement all circuits for powering 6000 corrector magnets with a maximum current of 600 A. To minimise the generation of ohmic heat in the cryogenic system, it is necessary to reduce the contact resistance of these connections as much as possible. This paper describes a method to measure contact resistances of splices of superconducting wires, which has been used to optimise such connections. Additionally we present results of a number of measurements on different types of connections. (2 refs).

  12. A controller design method for 3 phase 4 wire grid connected VSI ...

    Indian Academy of Sciences (India)

    Home; Journals; Sadhana; Volume 40; Issue 5. A controller design method for 3 phase 4 wire grid connected VSI with LCL filter. Anirban Ghoshal Vinod ... Asymptotic frequency response plot and gain bandwidth requirements of the system have been used for current control and voltage controller design. A simplified lower ...

  13. 24 CFR 3280.808 - Wiring methods and materials.

    Science.gov (United States)

    2010-04-01

    ... methods and materials specified in the National Electrical Code, NFPA No. 70-2005, must be used in....16(A) of the National Electrical Code, NFPA No. 70-2005, are permitted provided the box has been... Electrical Code, NFPA 70-2005, Article 314.23(B), or the brace, including the fastening mechanism to attach...

  14. Application of statistical methods at copper wire manufacturing

    Directory of Open Access Journals (Sweden)

    Z. Hajduová

    2009-01-01

    Full Text Available Six Sigma is a method of management that strives for near perfection. The Six Sigma methodology uses data and rigorous statistical analysis to identify defects in a process or product, reduce variability and achieve as close to zero defects as possible. The paper presents the basic information on this methodology.

  15. Study of structural and electronic environments of hydrogenated amorphous silicon carbonitride (a-SiCN:H) films deposited by hot wire chemical vapor deposition

    Science.gov (United States)

    Swain, Bibhu P.; Hwang, Nong M.

    2008-06-01

    Hydrogenated amorphous silicon carbon nitride (a-SiCN:H) thin films were deposited by hot wire chemical vapor deposition (HWCVD) using SiH 4, CH 4, NH 3 and H 2 as precursors. The effects of the H 2 dilution on structural and chemical bonding of a-SiCN:H has been investigated by Raman and X-ray photoelectron spectroscopy (XPS). Increasing the H 2 flow rate in the precursor gas more carbon is introduced into the a-SiCN:H network resulting in decrease of silicon content in the film from 41 at.% to 28.8 at.% and sp 2 carbon cluster increases when H 2 flow rate is increased from 0 to 20 sccm.

  16. Study of structural and electronic environments of hydrogenated amorphous silicon carbonitride (a-SiCN:H) films deposited by hot wire chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Swain, Bibhu P. [National Research Laboratory of Charged Nanoparticles, School of Materials Science and Engineering, Seoul National University, Seoul (Korea, Republic of)], E-mail: swain@snu.ac.kr; Hwang, Nong M. [National Research Laboratory of Charged Nanoparticles, School of Materials Science and Engineering, Seoul National University, Seoul (Korea, Republic of)

    2008-06-30

    Hydrogenated amorphous silicon carbon nitride (a-SiCN:H) thin films were deposited by hot wire chemical vapor deposition (HWCVD) using SiH{sub 4}, CH{sub 4}, NH{sub 3} and H{sub 2} as precursors. The effects of the H{sub 2} dilution on structural and chemical bonding of a-SiCN:H has been investigated by Raman and X-ray photoelectron spectroscopy (XPS). Increasing the H{sub 2} flow rate in the precursor gas more carbon is introduced into the a-SiCN:H network resulting in decrease of silicon content in the film from 41 at.% to 28.8 at.% and sp{sup 2} carbon cluster increases when H{sub 2} flow rate is increased from 0 to 20 sccm.

  17. Gas doping ratio effects on p-type hydrogenated nanocrystalline silicon thin films grown by hot-wire chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Luo, P.Q. [Solar Energy Institute, Department of Physics, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China)], E-mail: robt@sjtu.edu.cn; Zhou, Z.B. [Solar Energy Institute, Department of Physics, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China)], E-mail: zbzhou@sjtu.edu.cn; Chan, K.Y. [Thin Film Laboratory, Faculty of Engineering, Multimedia University, Jalan Multimedia, Cyberjaya 63100, Selangor (Malaysia); Tang, D.Y.; Cui, R.Q.; Dou, X.M. [Solar Energy Institute, Department of Physics, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China)

    2008-12-30

    Hydrogenated nanocrystalline silicon (nc-Si:H) grown by hot-wire chemical vapor deposition (HWCVD) has recently drawn significant attention in the area of thin-film large area optoelectronics due to possibility of high deposition rate. We report on the effects of diborane (B{sub 2}H{sub 6}) doping ratio on the microstructural and optoelectrical properties of the p-type nc-Si:H thin films grown by HWCVD at low substrate temperature of 200 deg. C and with high hydrogen dilution ratio of 98.8%. An attempt has been made to elucidate the boron doping mechanism of the p-type nc-Si:H thin films deposited by HWCVD and the correlation between the B{sub 2}H{sub 6} doping ratio, crystalline volume fraction, optical band gap and dark conductivity.

  18. Thermal stability of the optical band gap and structural order in hot-wire-deposited amorphous silicon

    CSIR Research Space (South Africa)

    Arendse, CJ

    2009-01-01

    Full Text Available The material properties of hydrogenated amorphous silicon (a-Si:H) have been known to change when exposed to elevated temperatures. In this work researchers report on the thermal stability of the optical band gap and structural disorder in hot...

  19. Time Reversal Method for Guided Waves with Multimode and Multipath on Corrosion Defect Detection in Wire

    Directory of Open Access Journals (Sweden)

    Yaoye Zhang

    2017-04-01

    Full Text Available This study identified depths of artificial pitting corrosion on the galvanized steel wires, frequently used in bridge cables, based on the time reversal method (TRM. Specifically, the multimode longitudinal ultrasonic guided waves are excited in terms of characteristics of radical distribution of the normalized average energy flow density (NAPFD in a wire. Furthermore, the complex defect scattered signals are difficult to interpret, which are attributed to multimode, multipath and dispersion, but are considered to enhance the focused energy through the TRM while the different depths of defect are explicitly identified by the normalized amplitudes of reconstructed wave packets. Finally, in contrast to the traditional monitoring approach relying on the amplitude of defect echo, the proposed method in this study is demonstrated to have a higher sensitivity to recognize the progressive increase of corrosion depth.

  20. Effect of wire shape on wire array discharge

    Energy Technology Data Exchange (ETDEWEB)

    Shimomura, N.; Tanaka, Y.; Yushita, Y.; Nagata, M. [University of Tokushima, Department of Electrical and Electronic Engineering, Tokushima (Japan); Teramoto, Y.; Katsuki, S.; Akiyama, H. [Kumamoto University, Department of Electrical and Computer Engineering, Kumamoto (Japan)

    2001-09-01

    Although considerable investigations have been reported on z-pinches to achieve nuclear fusion, little attention has been given from the point of view of how a wire array consisting of many parallel wires explodes. Instability existing in the wire array discharge has been shown. In this paper, the effect of wire shape in the wire array on unstable behavior of the wire array discharge is represented by numerical analysis. The claws on the wire formed in installation of wire may cause uniform current distribution on wire array. The effect of error of wire diameter in production is computed by Monte Carlo Method. (author)

  1. Transient Response of Thin Wire above a Layered Half-Space Using TDIE/FDTD Hybrid Method

    Directory of Open Access Journals (Sweden)

    Bing Wei

    2012-01-01

    Full Text Available The TDIE/FDTD hybrid method is applied to calculate the transient responses of thin wire above a lossy layered half-space. The time-domain reflection of the layered half space is computed by one-dimensional modified FDTD method. Then, transient response of thin wire induced by two excitation sources (the incident wave and reflected wave is calculated by TDIE method. Finally numerical results are given to illustrate the feasibility and high efficiency of the presented scheme.

  2. New low cost sensing head and taut wire method for automated straightness measurement of machine tool axes

    OpenAIRE

    Borisov, Oleg; Fletcher, Simon; Longstaff, Andrew P.; Myers, Alan

    2013-01-01

    This paper describes a novel method to measure straightness error of an axis of motion with a system utilizing taut wire, optical sensor and reference error cancellation technique. In contrast to commonly used taut wire, straightedge or laser-based methods it combines simplicity of setup and low cost with high levels of automation, accuracy and repeatability. An error cancellation technique based on two-point method is applied for the first time to a versatile reference object which can be mo...

  3. A New Method of Defects Identification for Wire Rope Based on Three-Dimensional Magnetic Flux Leakage

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, D L [Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen (China); Cao, Y N [Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen (China); Wang, C [Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen (China); Xu, D G [Electrical Engineering and Automation School, Harbin Institute of Technology, Harbin (China)

    2006-10-15

    Most traditional wire rope sensors produce the integrated volume of magnetic leakage around the whole circumference of wire rope, which is insensitive to the circumferential distribution of wire rope defects. In this paper the three-dimensional magnetic flux leakage of rope surface is obtained by the aid of Hall sensors array distributed around the wire rope. Then a spatial notch filter is designed to eliminate the strand-waveform signal, and the real defect signal is emphasized. The signal of any defect is transformed to the corresponding gray-scale map. Then an algorithm of two-dimensional image recognition is introduced to extract features from these gray-scale maps and identify defects. The experiment results show the degree and the width of defects, the circumferential distribution of localized flaw such as concentrated or dispersive broken wire can be well distinguished. The discrimination of this method for several typical defects under the condition of laboratory can reach 90%.

  4. Uniformity study of amorphous and microcrystalline silicon thin films deposited on 10cm x 10 cm glass substrate using hot wire CVD technique

    Energy Technology Data Exchange (ETDEWEB)

    Frigeri, P.A.; Nos, O.; Carreras, P.; Roldan, R.; Asensi, J.M.; Bertomeu, J. [Dept. de Fisica Aplicada i Optica, Universitat de Barcelona (Spain); Calvo, J.D. [Dept. de Fisica, Universidad Autonoma de Chiriqui, Chiriqui (Panama)

    2010-04-15

    The scaling up of the Hot Wire Chemical Vapor Deposition (HW-CVD) technique to large deposition area can be done using a catalytic net of equal spaced parallel filaments. The large area deposition limit is defined as the limit whenever a further increment of the catalytic net area does not affect the properties of the deposited film. This is the case when a dense catalytic net is spread on a surface considerably larger than that of the film substrate. To study this limit, a system able to hold a net of twelve wires covering a surface of about 20 cm x 20 cm was used to deposit amorphous (a-Si:H) and microcrystalline ({mu} c-Si:H) silicon over a substrate of 10 cm x 10 cm placed at a filament-substrate distance ranging from 1 to 2 cm. The uniformity of the film thickness d and optical constants, n (x, {lambda}) and {alpha} (x, {Dirac_h}{omega}), was studied via transmission measurements. The thin film uniformity as a function of the filament-substrate distance was studied. The experimental thickness profile was compared with the theoretical result obtained solving the diffusion equations. The optimization of the filament-substrate distance allowed obtaining films with inhomogeneities lower than {+-}2.5% and deposition rates higher than 1 nm/s and 4.5 nm/s for ({mu} c-Si:H) and (a-Si:H), respectively. (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  5. Evaluation of a countermeasure against wake galloping using wire connection method; Wake galloping ni taisuru seishin wire no yukosei ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, T.; Mukai, H.; Sano, N. [Kajima Corp., Tokyo (Japan)

    1994-10-31

    A plurality of parallel cables have been recently employed for long-span cable-stayed bridges. Use of such parallel cables thereupon leads to a special type of wind-induced vibration called wake galloping (simply referred to as WG.) owing to air turbulence caused by upstream cables. This paper attempts to evaluate measures against the WG using a wire connecting method, and identifies the most important influencing factor and the validity of the measures through wind tunnel tests. The following results are hereby clarified. Even if the deformation rigidity of the cables is increased, it is impossible to raise the wind velocity of the WG. The wind velocity of the WG can not be reduced from a wind tunnel wind velocity using non-dimensional wind velocity. The wire connecting method proves to be more effective for reducing the amplitude of the vibration. Provided cables are coupled into a multi-stage using the wire connection method, overall vibration with a greater amplitude can be restricted. To the factor of the restriction additional deformation rigidity of the cables more contributes compared with additional weight of the cables. 9 refs., 13 figs., 2 tabs.

  6. Parametric Optimization of Wire Electrical Discharge Machining of Powder Metallurgical Cold Worked Tool Steel using Taguchi Method

    Science.gov (United States)

    Sudhakara, Dara; Prasanthi, Guvvala

    2017-04-01

    Wire Cut EDM is an unconventional machining process used to build components of complex shape. The current work mainly deals with optimization of surface roughness while machining P/M CW TOOL STEEL by Wire cut EDM using Taguchi method. The process parameters of the Wire Cut EDM is ON, OFF, IP, SV, WT, and WP. L27 OA is used for to design of the experiments for conducting experimentation. In order to find out the effecting parameters on the surface roughness, ANOVA analysis is engaged. The optimum levels for getting minimum surface roughness is ON = 108 µs, OFF = 63 µs, IP = 11 A, SV = 68 V and WT = 8 g.

  7. Study of Electromagnetic Scattering From Material Object Doped Randomly With Thin Metallic Wires Using Finite Element Method

    Science.gov (United States)

    Deshpande, Manohar D.

    2005-01-01

    A new numerical simulation method using the finite element methodology (FEM) is presented to study electromagnetic scattering due to an arbitrarily shaped material body doped randomly with thin and short metallic wires. The FEM approach described in many standard text books is appropriately modified to account for the presence of thin and short metallic wires distributed randomly inside an arbitrarily shaped material body. Using this modified FEM approach, the electromagnetic scattering due to cylindrical, spherical material body doped randomly with thin metallic wires is studied.

  8. Searching for Hot Subdwarf Stars from the LAMOST Spectra. I. Method

    Science.gov (United States)

    Bu, Yude; Lei, Zhenxin; Zhao, Gang; Bu, Jingde; Pan, Jingchang

    2017-11-01

    Hot subdwarf stars are core He burning stars located at the blue end of the horizontal branch, which is also known as the extreme horizontal branch. The study of hot subdwarf stars is important for understanding stellar astrophysics, globular clusters, and galaxies. Presently, some problems associated with hot subdwarf stars are still unclear. To better study the properties of these stars, we should find more hot subdwarf stars to enlarge the sample size. The traditional method of searching for hot subdwarfs from the large data sets is based on the color cuts followed by visual inspection. This method is not suitable for the data set without homogeneous colors, such as the spectra obtained by the Large Sky Area Multi-object Fiber Spectroscopic Telescope (LAMOST). In this paper, we present a new method of searching for hot subdwarf stars in large spectroscopic surveys using a machine learning algorithm, the hierarchical extreme learning machine (HELM) algorithm. We have applied the HELM algorithm to the spectra from the LAMOST survey, and classification errors are considerably small: for the single hot subdwarf stars, accuracy = 0.92 and efficiency - 0.96; and for the hot subdwarf binaries, accuracy = 0.80 and efficiency = 0.71. A comparison of the HELM and other popular algorithms shows that HELM is accurate and efficient in classifying hot subdwarf stars. This method provides a new tool for searching for hot subdwarf stars in large spectroscopic surveys.

  9. Improved method for detection of “hot spots” in microelectronic devices

    Directory of Open Access Journals (Sweden)

    Popov V. M.

    2008-06-01

    Full Text Available New method of liquid crystal thermography of “hot spots” in crystals of microelectronic products have been developed. The method is based on the use of local cholesteric phase image of “hot spot” in transparent smectic phase of cholesteric liquid crystal against a background of clearly visible topological elements on the surface of microelectronic device crystal. Examples of “hot spot” images in crystals of different types of integrated circuits are shown.

  10. Nanocrystalline Si/SiO{sub 2} core-shell network with intense white light emission fabricated by hot-wire chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, Y., E-mail: ymatsumo@cinvestav.mx; Dutt, A. [SEES, Electrical Engineering Department, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Cinvestav-IPN, Mexico, D.F. 07360 (Mexico); Santana-Rodríguez, G. [Institute of Material Research, Universidad Nacional Autónoma de México, Coyoacán 04510 (Mexico); Santoyo-Salazar, J. [Department of Physics, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Cinvestav-IPN, Mexico, D.F. 07360 (Mexico); Aceves-Mijares, M. [Departament of Electronics, Instituto Nacional de Astrofísica Óptica y Electrónica, Tonantzintla, Puebla 72000 (Mexico)

    2015-04-27

    We report the fabrication of a stable Si/SiO{sub 2} core-shell network using hot-wire chemical vapor deposition on a silicon substrate at a relatively low substrate temperature of 200 °C. Structural investigations using transmission electron microscopy and X-ray diffraction confirm the presence of nanocrystalline silicon and silicon dioxide quantum dots in the form of a core-shell network embedded in the amorphous SiO{sub x} matrix, while selected area electron diffraction confirms the formation of a core-shell structure. The core-shell structure exhibits a bright white emission that can be seen with the unaided eye at room temperature without any post-annealing treatments, and the observed photoemission does not alter in color or intensity after prolonged laser exposure. Additional measurements are performed while varying the laser power and optical gain is found in the as-deposited material. Intense stable white luminescence is observed and shows the prospective for various optical and biological applications in the future.

  11. The influence of charge effect on the growth of hydrogenated amorphous silicon by the hot-wire chemical vapor deposition technique

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Q.; Nelson, B.P.; Iwaniczko, E.; Mahan, A.H.; Crandall, R.S.; Benner, J. [National Renewable Energy Lab., Golden, CO (United States)

    1998-09-01

    The authors observe at lower substrate temperatures that the scatter in the dark conductivity on hydrogenated amorphous silicon (a-Si:H) films grown on insulating substrates (e.g., Corning 7059 glass) by the hot-wire chemical vapor deposition technique (HWCVD) can be five orders of magnitude or more. This is especially true at deposition temperatures below 350 C. However, when the authors grow the same materials on substrates with a conductive grid, virtually all of their films have acceptable dark conductivity (< 5 {times} 10{sup {minus}10} S/cm) at all deposition temperatures below 425 C. This is in contrast to only about 20% of the materials grown in this same temperature range on insulating substrates having an acceptable dark conductivity. The authors estimated an average energy of 5 eV electrons reaching the growing surface in vacuum, and did additional experiments to see the influence of both the electron flux and the energy of the electrons on the film growth. Although these effects do not seem to be important for growing a-Si:H by HWCVD on conductive substrates, they help better understand the important parameters for a-Si:H growth, and thus, to optimize these parameters in other applications of HWCVD technology.

  12. From amorphous to nanocrystalline: the effect of nanograins in an amorphous matrix on the thermal conductivity of hot-wire chemical-vapor deposited silicon films

    Science.gov (United States)

    Kearney, B. T.; Jugdersuren, B.; Queen, D. R.; Metcalf, T. H.; Culbertson, J. C.; Desario, P. A.; Stroud, R. M.; Nemeth, W.; Wang, Q.; Liu, Xiao

    2018-02-01

    We have measured the thermal conductivity of amorphous and nanocrystalline silicon films with varying crystalline content from 85 K to room temperature. The films were prepared by the hot-wire chemical-vapor deposition, where the crystalline volume fraction is determined by the hydrogen (H2) dilution ratio to the processing silane gas (SiH4), R  =  H2/SiH4. We varied R from 1 to 10, where the films transform from amorphous for R  conductivities of the two amorphous silicon films are similar and consistent with the most previous reports with thicknesses no larger than a few μm deposited by a variety of techniques. The thermal conductivities of the three nanocrystalline silicon films are also similar, but are about 50–70% higher than those of their amorphous counterparts. The heat conduction in nanocrystalline silicon films can be understood as the combined contribution in both amorphous and nanocrystalline phases, where increased conduction through improved nanocrystalline percolation path outweighs increased interface scattering between silicon nanocrystals and the amorphous matrix.

  13. From Amorphous to Nanocrystalline: The Effect of Nanograins in Amorphous Matrix on the Thermal Conductivity of Hot-Wire Chemical-Vapor Deposited Silicon Films

    Energy Technology Data Exchange (ETDEWEB)

    Nemeth, William M [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kearney, B. T. [Naval Research Laboratory; Jugdersuren, B. [Sotera Defense Solutions Inc.; Queen, D. R. [Naval Research Laboratory; Metcalf, Thomas H. [Naval Research Laboratory; Culbertson, J. C. [Naval Research Laboratory; Desario, P. A. [Naval Research Laboratory; Stroud, R. M. [Naval Research Laboratory; Wang, Q. [Formerly NREL; Liu, Xiao [Naval Research Laboratory

    2017-12-28

    We have measured the thermal conductivity of amorphous and nanocrystalline silicon films with varying crystalline content from 85K to room temperature. The films were prepared by the hot-wire chemical-vapor deposition, where the crystalline volume fraction is determined by the hydrogen (H2) dilution ratio to the processing silane gas (SiH4), R=H2/SiH4. We varied R from 1 to 10, where the films transform from amorphous for R < 3 to mostly nanocrystalline for larger R. Structural analyses show that the nanograins, averaging from 2 to 9nm in sizes with increasing R, are dispersed in the amorphous matrix. The crystalline volume fraction increases from 0 to 65% as R increases from 1 to 10. The thermal conductivities of the two amorphous silicon films are similar and consistent with the most previous reports with thicknesses no larger than a few um deposited by a variety of techniques. The thermal conductivities of the three nanocrystalline silicon films are also similar, but are about 50-70% higher than those of their amorphous counterparts. The heat conduction in nanocrystalline silicon films can be understood as the combined contribution in both amorphous and nanocrystalline phases, where increased conduction through improved nanocrystalline percolation path outweighs increased interface scattering between silicon nanocrystals and the amorphous matrix.

  14. Testing of a hot- and cold-wire probe to measure simultaneously the speed and temperature in supercritical CO{sub 2} flow

    Energy Technology Data Exchange (ETDEWEB)

    Vukoslavcevic, Petar V.; Radulovic, Ivana M. [University of Montenegro, Podgorica (Czechoslovakia); Wallace, James M. [University of Maryland, MD (United States)

    2005-10-01

    The use of hot-wire anemometry in carbon dioxide flow under supercritical conditions has been analyzed and implemented for the first time. A two-sensor probe to simultaneously measure streamwise velocity and temperature in this flow has been designed and constructed. A calibration and test flow loop that can provide supercritical state conditions above the critical point has been also designed, fabricated and tested. The temperature and velocity flow fields of the flow loop can be varied at constant pressure. It has been found that, above the pseudo-critical temperature, the velocity sensor response fits King's cooling law with a high correlation coefficient. The dependence of the King's law parameters on temperature can be accurately presented with second or higher order polynomial or exponential fits, depending on the extent of the temperature range. Below the pseudocritical temperature the data is scattered, and the variation with temperature of the King's law parameters, determined from calibration, is irregular. The influence on this data scatter of the strong variation of the fluid properties near the critical point is analyzed, and a possibility to reduce it is proposed. The temperature sensor response both above and below the pseudocritical temperature is similar to the response under normal conditions. It is linear with a very high correlation coefficient between the calibration data and the fitted curve. It is also shown that the temperature response is not affected by variation of the flow's speed. (orig.)

  15. Feasibility of an electromagnetic compatibility method for MRgFUS using a wire mesh screen.

    Science.gov (United States)

    Wu, Hao; Shen, Guofeng; Chen, Yazhu

    2016-12-01

    This study evaluated an electromagnetic compatibility method for high-intensity focused ultrasound (HIFU) and magnetic resonance (MR) imaging in an MR-guided focused ultrasound surgery using a conductive wire mesh screen. This screen has a good ultrasound transmission and shielding effectiveness. A hybrid acoustic simulation method was developed to analyze the effects of mesh parameters and the HIFU working frequency on the acoustic field. Experiments were performed to measure both acoustic pressure profile and radiated electromagnetic noise. With the proposed mesh screen, the electromagnetic radiation emission was reduced by 14dB at 128MHz while the acoustic focal intensity was reduced by less than 11% using one screen. This shielding method is easy to implement and requires no additional phase correction method. This method also improves the quality of MR images. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Thermo-Electrical Mathematical Model for Prediction of Ni-Cr Hot-Wire Temperature in Free Air and Inside Small Circular Cavities

    DEFF Research Database (Denmark)

    Petkov, Kiril; Hattel, Jesper Henri

    2017-01-01

    A one-dimensional thermo-electrical mathematical model describing the heating and cooling of thin Ni-Cr20% wires is presented. The model is applied for wires in a free air environment and to wires placed in small circular cavities formed by expanded polystyrene material. The basis of the model...

  17. Investigation of the beryllia ceramics molding process by the hot casting method

    Science.gov (United States)

    Zhapbasbaev, U. K.; Ramazanova, G. I.; Sattinova, Z. K.

    2013-03-01

    Results of mathematical simulation of the ceramics molding process by the hot casting method are presented. The mathematical model describes the motion of beryllia liquid thermoplastic slurry in a form-building cavity subject to solidification. Velocity and temperature profiles providing homogeneous properties of the beryllia ceramics in the process of molding by the hot casting method are obtained.

  18. Fixation of patella fractures with a minimally invasive tensioned wire method: compressive external fixation.

    Science.gov (United States)

    Wardak, Mohammed Ismail; Siawash, Abdul Razaqu; Hayda, Roman

    2012-05-01

    Current fixation methods of patella fractures are associated with hardware prominence, infection, and failure of fixation. These complications necessitate repeat surgical treatment, increase costs, and limit function. We investigated whether a novel device can effectively treat patella fractures with few complications. A consecutive series of patients with displaced patella fractures with transverse and select other patterns were treated with the technique of compressive external fixation (CEF), a device based on an external tensioned wire construct. Patients were allowed unrestricted motion and weight bearing postoperatively. Patient outcomes were evaluated retrospectively. Eighty-four fractures (26 open) were treated with CEF with 23 performed percutaneously. All of the fractures attained union. The device was removed in the office at 6 weeks. Sixty-one patients regained excellent motion with a mean Insall knee score of 97 points, at an average follow-up of 4 years. Minor complications presented in 11% of patients but did not affect the overall outcome. Complications included minor wire irritation in 14 patients and one case of poor knee motion in a patient presenting with fibroankylosis of the joint. Treatment using the CEF technique is a safe and effective method of treatment of patella fractures with advantages over traditional forms of fixation particularly in cases with a poor soft tissue envelope, salvage situations, and in locations with limited resources. It allows for rapid recovery with minimal complications and no secondary surgery. Its use should be considered in the treatment of these injuries. V, therapeutic study.

  19. Measurement method of magnetic field for the wire suspended micro-pendulum accelerometer.

    Science.gov (United States)

    Lu, Yongle; Li, Leilei; Hu, Ning; Pan, Yingjun; Ren, Chunhua

    2015-04-13

    Force producer is one of the core components of a Wire Suspended Micro-Pendulum Accelerometer; and the stability of permanent magnet in the force producer determines the consistency of the acceleration sensor's scale factor. For an assembled accelerometer; direct measurement of magnetic field strength is not a feasible option; as the magnetometer probe cannot be laid inside the micro-space of the sensor. This paper proposed an indirect measurement method of the remnant magnetization of Micro-Pendulum Accelerometer. The measurement is based on the working principle of the accelerometer; using the current output at several different scenarios to resolve the remnant magnetization of the permanent magnet. Iterative Least Squares algorithm was used for the adjustment of the data due to nonlinearity of this problem. The calculated remnant magnetization was 1.035 T. Compared to the true value; the error was less than 0.001 T. The proposed method provides an effective theoretical guidance for measuring the magnetic field of the Wire Suspended Micro-Pendulum Accelerometer; correcting the scale factor and temperature influence coefficients; etc.

  20. Measurement Method of Magnetic Field for the Wire Suspended Micro-Pendulum Accelerometer

    Directory of Open Access Journals (Sweden)

    Yongle Lu

    2015-04-01

    Full Text Available Force producer is one of the core components of a Wire Suspended Micro-Pendulum Accelerometer; and the stability of permanent magnet in the force producer determines the consistency of the acceleration sensor’s scale factor. For an assembled accelerometer; direct measurement of magnetic field strength is not a feasible option; as the magnetometer probe cannot be laid inside the micro-space of the sensor. This paper proposed an indirect measurement method of the remnant magnetization of Micro-Pendulum Accelerometer. The measurement is based on the working principle of the accelerometer; using the current output at several different scenarios to resolve the remnant magnetization of the permanent magnet. Iterative Least Squares algorithm was used for the adjustment of the data due to nonlinearity of this problem. The calculated remnant magnetization was 1.035 T. Compared to the true value; the error was less than 0.001 T. The proposed method provides an effective theoretical guidance for measuring the magnetic field of the Wire Suspended Micro-Pendulum Accelerometer; correcting the scale factor and temperature influence coefficients; etc.

  1. Research on the Statistical Characteristics of Crosstalk in Naval Ships Wiring Harness Based on Polynomial Chaos Expansion Method

    Directory of Open Access Journals (Sweden)

    Chi Yaodan

    2017-08-01

    Full Text Available Crosstalk in wiring harness has been studied extensively for its importance in the naval ships electromagnetic compatibility field. An effective and high-efficiency method is proposed in this paper for analyzing Statistical Characteristics of crosstalk in wiring harness with random variation of position based on Polynomial Chaos Expansion (PCE. A typical 14-cable wiring harness was simulated as the object of research. Distance among interfering cable, affected cable and GND is synthesized and analyzed in both frequency domain and time domain. The model of naval ships wiring harness distribution parameter was established by utilizing Legendre orthogonal polynomials as basis functions along with prediction model of statistical characters. Detailed mean value, mean square error, probability density function and reasonable varying range of crosstalk in naval ships wiring harness are described in both time domain and frequency domain. Numerical experiment proves that the method proposed in this paper, not only has good consistency with the MC method can be applied in the naval ships EMC research field to provide theoretical support for guaranteeing safety, but also has better time-efficiency than the MC method. Therefore, the Polynomial Chaos Expansion method.

  2. Deformation Behavior of Powder Metallurgy Connecting Rod Preform During Hot Forging Based on Hot Compression and Finite Element Method Simulation

    Science.gov (United States)

    Li, Fengxian; Yi, Jianhong; Eckert, Jürgen

    2017-06-01

    Powder-forged connecting rod with a complex geometry shape always has a problem with nonuniform density distribution. Moreover, the physical property of preform plays a critical role for optimizing the connecting rod quality. The flow behavior of a Fe-3Cu-0.5C (wt pct) alloy with a relative density of 0.8 manufactured by powder metallurgy (P/M, Fe-Cu-C) was studied using isothermal compression tests. The material constitutive equation, power dissipation ( η) maps, and hot processing maps of the P/M Fe-Cu-C alloy were established. Then, the hot forging process of the connecting rod preforms was simulated using the material constitutive model based on finite element method simulation. The calculated results agree well with the experimental ones. The results show that the flow stress increases with decreasing temperature and increasing strain rate. The activation energy of the P/M Fe-Cu-C alloy with a relative density of 0.8 is 188.42 kJ/mol. The optimum temperature at the strain of 0.4 for good hot workability of sintered Fe-Cu-C alloy ranges from 1333 K to 1380 K (1060 °C to 1107 °C). The relative density of the hot-forged connecting rod at the central part changed significantly compared with that at the big end and that at the small end. These present theoretical and experimental investigations can provide a methodology for accurately predicting the densification behavior of the P/M connecting rod preform during hot forging, and they help to optimize the processing parameters.

  3. Developing Light Collection Enhancements and Wire Tensioning Methods for LArTPC Neutrino Detectors

    Energy Technology Data Exchange (ETDEWEB)

    Spagliardi, Fabio [Univ. of Manchester (United Kingdom)

    2017-01-01

    Liquid argon Time Projection Chambers (LArTPCs) are becoming widely used as neutrino detectors because of their image-like event reconstruction which enables precision neutrino measurements. They primarily use ionisation charge to reconstruct neutrino events. It has been shown, however, that the scintillation light emitted by liquid argon could be exploited to improve their performance. As the neutrino measurements planned in the near future require large-scale experiments, their construction presents challenges in terms of both charge and light collection. In this dissertation we present solutions developed to improve the performance in both aspects of these detectors. We present a new wire tensioning measurement method that allows a remote measurement of the tension of the large number wires that constitute the TPC anode. We also discuss the development and installation of WLS-compound covered foils for the SBND neutrino detector at Fermilab, which is a technique proposed t o augment light collection in LArTPCs. This included preparing a SBND-like mesh cathode and testing it in the Run III of LArIAT, a test beam detector also located at Fermilab. Finally, we present a study aimed at understanding late scintillation light emitted by recombining positive argon ions using LArIAT data, which could affect large scale surface detectors.

  4. Wire bonding in microelectronics

    CERN Document Server

    Harman, George G

    2010-01-01

    Wire Bonding in Microelectronics, Third Edition, has been thoroughly revised to help you meet the challenges of today's small-scale and fine-pitch microelectronics. This authoritative guide covers every aspect of designing, manufacturing, and evaluating wire bonds engineered with cutting-edge techniques. In addition to gaining a full grasp of bonding technology, you'll learn how to create reliable bonds at exceedingly high yields, test wire bonds, solve common bonding problems, implement molecular cleaning methods, and much more. Coverage includes: Ultrasonic bonding systems and technologies, including high-frequency systems Bonding wire metallurgy and characteristics, including copper wire Wire bond testing Gold-aluminum intermetallic compounds and other interface reactions Gold and nickel-based bond pad plating materials and problems Cleaning to improve bondability and reliability Mechanical problems in wire bonding High-yield, fine-pitch, specialized-looping, soft-substrate, and extreme-temperature wire bo...

  5. Theories, Methods and Numerical Technology of Sheet Metal Cold and Hot Forming Analysis, Simulation and Engineering Applications

    CERN Document Server

    Hu, Ping; Liu, Li-zhong; Zhu, Yi-guo

    2013-01-01

    Over the last 15 years, the application of innovative steel concepts in the automotive industry has increased steadily. Numerical simulation technology of hot forming of high-strength steel allows engineers to modify the formability of hot forming steel metals and to optimize die design schemes. Theories, Methods and Numerical Technology of Sheet Metal Cold and Hot Forming focuses on hot and cold forming theories, numerical methods, relative simulation and experiment techniques for high-strength steel forming and die design in the automobile industry. Theories, Methods and Numerical Technology of Sheet Metal Cold and Hot Forming introduces the general theories of cold forming, then expands upon advanced hot forming theories and simulation methods, including: • the forming process, • constitutive equations, • hot boundary constraint treatment, and • hot forming equipment and experiments. Various calculation methods of cold and hot forming, based on the authors’ experience in commercial CAE software f...

  6. Magnetic field measurements of the CEBAF (NIST) wiggler using the pulsed wire method

    Science.gov (United States)

    Wallace, Stephen M.

    1992-09-01

    The Free Electron Laser (FEL) has proven to be a versatile photon source for many applications in science, industry, and defense. It is capable of providing wide tunability and high efficiency, but has yet to yield high average power required as a weapon system. The proposed infrared and ultraviolet FELs at the Continuous Electron Beam Accelerator Facility (CEBAF) have been projected to provide high average power. The first section of this thesis will study the necessity of a FEL for shipboard defense, and state the advantages over other defense systems. The remainder will focus on use of the pulsed wire method for measuring the magnetic field errors of the CEBAF/National Institute of Science and Technology (NIST) wiggler. Data analysis indicates the wiggler will have a net electron beam deflection of x = 5.2 mm, which is much greater than the electron beam radius of re = 0.4 mm and the optical mode waist of wo = 1 mm.

  7. Biomechanical Comparison of 2 Methods of Intramedullary K-Wire Fixation of Transverse Metacarpal Shaft Fractures.

    Science.gov (United States)

    Hiatt, Stephen V; Begonia, Mark T; Thiagarajan, Ganesh; Hutchison, Richard L

    2015-08-01

    To determine the relative importance of intramedullary wire (IMW) diameter and IMW number in conferring stability to a metacarpal fracture fixation construct. Our research hypothesis was that the stiffness of IMW fixation for metacarpal shaft fractures using a single 1.6-mm-diameter (0.062-in) wire would be greater than three 0.8-mm-diameter (0.031-in) wires. Our study compared the biomechanical stiffness between one 1.6-mm K-wire and three 0.8-mm K-wires in a composite, fourth-generation, biomechanical metacarpal construct under cantilever testing to treat transverse metacarpal shaft fractures. Six composite bone-wire constructs were tested in each group using constant-rate, nondestructive testing. Stiffness (load/displacement) was measured for each construct. All constructs demonstrated a linear load-displacement relationship. Wires were all tested in their elastic zone. The mean stiffness of the 1-wire construct was 3.20 N/mm and the mean stiffness of the 3-wire construct was 0.76 N/mm. These differences were statistically significant with a large effect size. The stiffness of IMW fixation for metacarpal shaft fractures using a single 1.6-mm-diameter wire was significantly greater than using three 0.8-mm-diameter wires. When IMW fixation is clinically indicated for the treatment of metacarpal fractures, the increased stiffness of a single large-diameter construct provides more stability in the plane of finger flexion-extension. Copyright © 2015 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  8. Cable Crosstalk Suppression in Resistive Sensor Array with 2-Wire S-NSDE-EP Method

    Directory of Open Access Journals (Sweden)

    JianFeng Wu

    2016-01-01

    Full Text Available With long flexible cables connected to the 1-wire setting non-scanned-driving-electrode equipotential (S-NSDE-EP circuit, the resistive sensor array modules got flexibility in robotic operations but suffered from the crosstalk problem caused by wire resistances and contacted resistances of the cables. Firstly, we designed a new S-NSDE-EP circuit using two wires for every driving-electrode and every sampling-electrode to reduce the crosstalk caused by the connected cables in the 2D networked resistive sensor array. Then, an equivalent resistance expression of the element being tested (EBT for this circuit was analytically derived. Then, the 1-wire S-NSDE-EP circuit and the 2-wire S-NSDE-EP circuit were evaluated by simulations. The simulation results show that the 2-wire S-NSDE-EP circuit, though it requires a large number of wires, can greatly reduce the crosstalk error caused by wire resistances and contacted resistances of the cables in the 2D networked resistive sensor array.

  9. Measurement of proton capture reactions in the hot cycles: an evaluation of experimental methods

    Energy Technology Data Exchange (ETDEWEB)

    Leleux, P. [Inst. de Physique Nucleaire, Univ. Catholique de Louvain, Louvain-la-Neuve (Belgium)

    1998-06-01

    In the hot cycles, most of the proton capture reactions involve radioactive nuclei in the entrance and exit channels. This paper evaluates the specific methods that were designed to measure such reactions. (orig.)

  10. A High-Fidelity Haze Removal Method Based on HOT for Visible Remote Sensing Images

    Directory of Open Access Journals (Sweden)

    Hou Jiang

    2016-10-01

    Full Text Available Spatially varying haze is a common feature of most satellite images currently used for land cover classification and mapping and can significantly affect image quality. In this paper, we present a high-fidelity haze removal method based on Haze Optimized Transformation (HOT, comprising of three steps: semi-automatic HOT transform, HOT perfection and percentile based dark object subtraction (DOS. Since digital numbers (DNs of band red and blue are highly correlated in clear sky, the R-squared criterion is utilized to search the relative clearest regions of the whole scene automatically. After HOT transform, spurious HOT responses are first masked out and filled by means of four-direction scan and dynamic interpolation, and then homomorphic filter is performed to compensate for loss of HOT of masked-out regions with large areas. To avoid patches and halo artifacts, a procedure called percentile DOS is implemented to eliminate the influence of haze. Scenes including various land cover types are selected to validate the proposed method, and a comparison analysis with HOT and Background Suppressed Haze Thickness Index (BSHTI is performed. Three quality assessment indicators are selected to evaluate the haze removed effect on image quality from different perspective and band profiles are utilized to analyze the spectral consistency. Experiment results verify the effectiveness of the proposed method for haze removal and the superiority of it in preserving the natural color of object itself, enhancing local contrast, and maintaining structural information of original image.

  11. Method for Hot Real-Time Sampling of Pyrolysis Vapors

    Energy Technology Data Exchange (ETDEWEB)

    Pomeroy, Marc D [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-09-29

    Biomass Pyrolysis has been an increasing topic of research, in particular as a replacement for crude oil. This process utilizes moderate temperatures to thermally deconstruct the biomass which is then condensed into a mixture of liquid oxygenates to be used as fuel precursors. Pyrolysis oils contain more than 400 compounds, up to 60 percent of which do not re-volatilize for subsequent chemical analysis. Vapor chemical composition is also complicated as additional condensation reactions occur during the condensation and collection of the product. Due to the complexity of the pyrolysis oil, and a desire to catalytically upgrade the vapor composition before condensation, online real-time analytical techniques such as Molecular Beam Mass Spectrometry (MBMS) are of great use. However, in order to properly sample hot pyrolysis vapors, many challenges must be overcome. Sampling must occur within a narrow range of temperatures to reduce product composition changes from overheating or partial condensation or plugging of lines from condensed products. Residence times must be kept at a minimum to reduce further reaction chemistries. Pyrolysis vapors also form aerosols that are carried far downstream and can pass through filters resulting in build-up in downstream locations. The co-produced bio-char and ash from the pyrolysis process can lead to plugging of the sample lines, and must be filtered out at temperature, even with the use of cyclonic separators. A practical approach for considerations and sampling system design, as well as lessons learned are integrated into the hot analytical sampling system of the National Renewable Energy Laboratory's (NREL) Thermochemical Process Development Unit (TCPDU) to provide industrially relevant demonstrations of thermochemical transformations of biomass feedstocks at the pilot scale.

  12. Method of Obtaining High Resolution Intrinsic Wire Boom Damping Parameters for Multi-Body Dynamics Simulations

    Science.gov (United States)

    Yew, Alvin G.; Chai, Dean J.; Olney, David J.

    2010-01-01

    The goal of NASA's Magnetospheric MultiScale (MMS) mission is to understand magnetic reconnection with sensor measurements from four spinning satellites flown in a tight tetrahedron formation. Four of the six electric field sensors on each satellite are located at the end of 60- meter wire booms to increase measurement sensitivity in the spin plane and to minimize motion coupling from perturbations on the main body. A propulsion burn however, might induce boom oscillations that could impact science measurements if oscillations do not damp to values on the order of 0.1 degree in a timely fashion. Large damping time constants could also adversely affect flight dynamics and attitude control performance. In this paper, we will discuss the implementation of a high resolution method for calculating the boom's intrinsic damping, which was used in multi-body dynamics simulations. In summary, experimental data was obtained with a scaled-down boom, which was suspended as a pendulum in vacuum. Optical techniques were designed to accurately measure the natural decay of angular position and subsequently, data processing algorithms resulted in excellent spatial and temporal resolutions. This method was repeated in a parametric study for various lengths, root tensions and vacuum levels. For all data sets, regression models for damping were applied, including: nonlinear viscous, frequency-independent hysteretic, coulomb and some combination of them. Our data analysis and dynamics models have shown that the intrinsic damping for the baseline boom is insufficient, thereby forcing project management to explore mitigation strategies.

  13. Method for Hot Real-Time Sampling of Gasification Products

    Energy Technology Data Exchange (ETDEWEB)

    Pomeroy, Marc D [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-09-29

    The Thermochemical Process Development Unit (TCPDU) at the National Renewable Energy Laboratory (NREL) is a highly instrumented half-ton/day pilot scale plant capable of demonstrating industrially relevant thermochemical technologies from lignocellulosic biomass conversion, including gasification. Gasification creates primarily Syngas (a mixture of Hydrogen and Carbon Monoxide) that can be utilized with synthesis catalysts to form transportation fuels and other valuable chemicals. Biomass derived gasification products are a very complex mixture of chemical components that typically contain Sulfur and Nitrogen species that can act as catalysis poisons for tar reforming and synthesis catalysts. Real-time hot online sampling techniques, such as Molecular Beam Mass Spectrometry (MBMS), and Gas Chromatographs with Sulfur and Nitrogen specific detectors can provide real-time analysis providing operational indicators for performance. Sampling typically requires coated sampling lines to minimize trace sulfur interactions with steel surfaces. Other materials used inline have also shown conversion of sulfur species into new components and must be minimized. Sample line Residence time within the sampling lines must also be kept to a minimum to reduce further reaction chemistries. Solids from ash and char contribute to plugging and must be filtered at temperature. Experience at NREL has shown several key factors to consider when designing and installing an analytical sampling system for biomass gasification products. They include minimizing sampling distance, effective filtering as close to source as possible, proper line sizing, proper line materials or coatings, even heating of all components, minimizing pressure drops, and additional filtering or traps after pressure drops.

  14. Assessment of the hardness of different orthodontic wires and brackets produced by metal injection molding and conventional methods.

    Science.gov (United States)

    Alavi, Shiva; Kachuie, Marzie

    2017-01-01

    This study was conducted to assess the hardness of orthodontic brackets produced by metal injection molding (MIM) and conventional methods and different orthodontic wires (stainless steel, nickel-titanium [Ni-Ti], and beta-titanium alloys) for better clinical results. A total of 15 specimens from each brand of orthodontic brackets and wires were examined. The brackets (Elite Opti-Mim which is produced by MIM process and Ultratrimm which is produced by conventional brazing method) and the wires (stainless steel, Ni-Ti, and beta-titanium) were embedded in epoxy resin, followed by grinding, polishing, and coating. Then, X-ray energy dispersive spectroscopy (EDS) microanalysis was applied to assess their elemental composition. The same specimen surfaces were repolished and used for Vickers microhardness assessment. Hardness was statistically analyzed with Kruskal-Wallis test, followed by Mann-Whitney test at the 0.05 level of significance. The X-ray EDS analysis revealed different ferrous or co-based alloys in each bracket. The maximum mean hardness values of the wires were achieved for stainless steel (SS) (529.85 Vickers hardness [VHN]) versus the minimum values for beta-titanium (334.65 VHN). Among the brackets, Elite Opti-Mim exhibited significantly higher VHN values (262.66 VHN) compared to Ultratrimm (206.59 VHN). VHN values of wire alloys were significantly higher than those of the brackets. MIM orthodontic brackets exhibited hardness values much lower than those of SS orthodontic archwires and were more compatible with NiTi and beta-titanium archwires. A wide range of microhardness values has been reported for conventional orthodontic brackets and it should be considered that the manufacturing method might be only one of the factors affecting the mechanical properties of orthodontic brackets including hardness.

  15. Wire + Arc Additive Manufacturing

    OpenAIRE

    Williams, Stewart W.; Martina, Filomeno; Addison, Adrian C.; Ding, Jialuo; Pardal, Goncalo; Colegrove, Paul A.

    2016-01-01

    Depositing large components (>10 kg) in titanium, aluminium, steel and other metals is possible using Wire + Arc Additive Manufacturing. This technology adopts arc welding tools and wire as feedstock for additive manufacturing purposes. High deposition rates, low material and equipment costs, and good structural integrity make Wire+Arc Additive Manufacturing a suitable candidate for replacing the current method of manufacturing from solid billets or large forgings, especially with regards to ...

  16. Calculation methods study on hot spot stress of new girder structure detail

    Science.gov (United States)

    Liao, Ping; Zhao, Renda; Jia, Yi; Wei, Xing

    2017-10-01

    To study modeling calculation methods of new girder structure detail's hot spot stress, based on surface extrapolation method among hot spot stress method, a few finite element analysis models of this welded detail were established by finite element software ANSYS. The influence of element type, mesh density, different local modeling methods of the weld toe and extrapolation methods was analyzed on hot spot stress calculation results at the toe of welds. The results show that the difference of the normal stress in the thickness direction and the surface direction among different models is larger when the distance from the weld toe is smaller. When the distance from the toe is greater than 0.5t, the normal stress of solid models, shell models with welds and non-weld shell models tends to be consistent along the surface direction. Therefore, it is recommended that the extrapolated point should be selected outside the 0.5t for new girder welded detail. According to the results of the calculation and analysis, shell models have good grid stability, and extrapolated hot spot stress of solid models is smaller than that of shell models. So it is suggested that formula 2 and solid45 should be carried out during the hot spot stress extrapolation calculation of this welded detail. For each finite element model under different shell modeling methods, the results calculated by formula 2 are smaller than those of the other two methods, and the results of shell models with welds are the largest. Under the same local mesh density, the extrapolated hot spot stress decreases gradually with the increase of the number of layers in the thickness direction of the main plate, and the variation range is within 7.5%.

  17. Efficacy of brown sugar flotation and hot water methods for detecting Rhagoletis indifferens (Dipt., Tephritidae) larvae

    Science.gov (United States)

    The brown sugar flotation and hot water methods are accepted procedures for detecting larval western cherry fruit fly, Rhagoletis indifferens Curran, in sweet cherry [Prunus avium (L.) L.] and could be included in a systems approach for showing the absence of larvae in fruit. The methods require cr...

  18. Non-parametric method for separating domestic hot water heating spikes and space heating

    DEFF Research Database (Denmark)

    Bacher, Peder; de Saint-Aubain, Philip Anton; Christiansen, Lasse Engbo

    2016-01-01

    In this paper a method for separating spikes from a noisy data series, where the data change and evolve over time, is presented. The method is applied on measurements of the total heat load for a single family house. It relies on the fact that the domestic hot water heating is a process generatin...

  19. Estimation of the Level of Residual Stress in Wires with a Magnetic Method

    Directory of Open Access Journals (Sweden)

    Suliga M.

    2015-04-01

    Full Text Available Residual stress present in wires after drawing process affects their magnetic properties. The paper presents a concept to estimate the level of residual stress on the basis of measurements of hysteresis loops. In order to describe the effect qualitatively the Jiles-Atherton-Sablik description is adapted. On the basis of variations in hysteresis loop shapes the average values of residual stress in wires for different single draft values are determined. It was found that the estimated average values by magnetic stresses are comparable with the results of numerical modeling and experimental studies.

  20. New low cost sensing head and taut wire method for automated straightness measurement of machine tool axes

    Science.gov (United States)

    Borisov, Oleg; Fletcher, Simon; Longstaff, Andrew; Myers, Alan

    2013-08-01

    This paper describes a novel method to measure straightness error of an axis of motion with a system utilising taut wire, optical sensor and reference error cancellation technique. In contrast to commonly used taut wire, straightedge or laser-based methods it combines simplicity of setup and low cost with high levels of automation, accuracy and repeatability. An error cancellation technique based on two-point method is applied for the first time to a versatile reference object which can be mounted at any place of machine's working volume allowing direct measurement of motion straightness of a tool point. Experimental results on a typical machine tool validate performance of the proposed taut wire system with a commercial laser interferometer operating in the same conditions is used as a reference. The proposed method shows highly repeatable results of better than ±0.25 μm over the range of 0.48 m and measurement accuracy comparable to the interferometer of ±0.5 μm.

  1. Protein binding hot spots prediction from sequence only by a new ensemble learning method.

    Science.gov (United States)

    Hu, Shan-Shan; Chen, Peng; Wang, Bing; Li, Jinyan

    2017-10-01

    Hot spots are interfacial core areas of binding proteins, which have been applied as targets in drug design. Experimental methods are costly in both time and expense to locate hot spot areas. Recently, in-silicon computational methods have been widely used for hot spot prediction through sequence or structure characterization. As the structural information of proteins is not always solved, and thus hot spot identification from amino acid sequences only is more useful for real-life applications. This work proposes a new sequence-based model that combines physicochemical features with the relative accessible surface area of amino acid sequences for hot spot prediction. The model consists of 83 classifiers involving the IBk (Instance-based k means) algorithm, where instances are encoded by important properties extracted from a total of 544 properties in the AAindex1 (Amino Acid Index) database. Then top-performance classifiers are selected to form an ensemble by a majority voting technique. The ensemble classifier outperforms the state-of-the-art computational methods, yielding an F1 score of 0.80 on the benchmark binding interface database (BID) test set. http://www2.ahu.edu.cn/pchen/web/HotspotEC.htm .

  2. Measurement of the thermal conductivity of thin insulating anisotropic material with a stationary hot strip method

    Science.gov (United States)

    Jannot, Yves; Degiovanni, Alain; Félix, Vincent; Bal, Harouna

    2011-03-01

    This paper presents a method dedicated to the thermal conductivity measurement of thin insulating anisotropic materials. The method is based on three hot-strip-type experiments in which the stationary temperature is measured at the center of the hot strip. A 3D model of the heat transfer in the system is established and simulated to determine the validity of a 2D transfer hypothesis at the center of the hot strip. A simplified 2D model is then developed leading to the definition of a geometrical factor calculable from a polynomial expression. A very simple calculation method enabling the estimation of the directional thermal conductivities from the three stationary temperature measurements and from the geometrical factor is presented. The uncertainties on each conductivity are estimated. The method is then validated by measurements on polyethylene foam and Ayous (anistropic low-density tropical wood); the estimated values of the thermal conductivities are in good agreement with the values estimated using the hot plate and the flash method. The method is finally applied on a thin super-insulating fibrous material for which no other method is able to measure the in-plane conductivity.

  3. Comparing Rotary Bend Wire Fatigue Test Methods at Different Test Speeds

    Science.gov (United States)

    Weaver, Jason D.; Gutierrez, Erick J.

    2015-12-01

    Given its relatively simple setup and ability to produce results quickly, rotary bend fatigue testing is becoming commonplace in the medical device industry and is the subject of a new standard test method ASTM E2948-14. Although some research has been conducted to determine if results differ for different rotary bend fatigue test setups or test speeds, these parameters have not been extensively studied together. In this work, we investigate the effects of these two parameters on the fatigue life of three commonly used medical device alloys (ASTM F2063 nitinol, ASTM F138 stainless steel, and ASTM F1058 cobalt chromium). Results with three different rotary bend fatigue test setups revealed no difference in fatigue life among those setups. Increasing test speed, however, between 100 and 35,000 RPM led to an increased fatigue life for all three alloys studied (average number of cycles to fracture increased between 2.0 and 5.1 times between slowest and fastest test speed). Supplemental uniaxial tension tests of stainless steel wire at varying strain rates showed a strain rate dependence in the mechanical response which could in part explain the increased fatigue life at faster test speeds. How exactly strain rate dependence might affect the fatigue properties of different alloys at different alternating strain values requires further study. Given the difference in loading rates between benchtop fatigue tests and in vivo deformations, the potential for strain rate dependence should be considered when designing durability tests for medical devices and in extrapolating results of those tests to in vivo performance.

  4. Modeling Material Flow Behavior during Hot Deformation Based on Metamodeling Methods

    Directory of Open Access Journals (Sweden)

    Gang Xiao

    2015-01-01

    Full Text Available Modeling material flow behavior is an essential step to design and optimize the forming process. In this context, four popular metamodel types Kriging, radial basis function, multivariate polynomial, and artificial neural network are investigated as potential methods for modeling the flow behavior of 6013 aluminum alloy. Based on the experimental data from hot compression tests, the modeling performance of these four methods was tested and subsequently compared from different aspects. It is found that all the methods are capable of constructing models for describing the hot deformation behavior. The merits of Kriging method over other three methods are highlighted when the sample size for modeling is decreased. Furthermore, the applicability of Kriging method is validated while decreasing the sample uniformity with respect to temperature or strain rate. It is proved that Kriging method is competent in modeling the material flow behavior and is the most effective one among the four popular types of metamodeling method.

  5. Implementation and Applications of the Method of Auxiliary Sources for Analysis of Smooth Scatterers and Wires

    DEFF Research Database (Denmark)

    Larsen, Niels Vesterdal

    2007-01-01

    to investigate finite ground planes, dielectric resonator antennas and arrays, and arrays of wire antennas. The described techniques are compared with reference results with good resulting agreement. In addition some representative examples of application are given which, for the most part, are of similar nature...

  6. A Method For The Verification Of Wire Crimp Compression Using Ultrasonic Inspection

    Science.gov (United States)

    Cramer, K. E.; Perey, Daniel F.; Yost, William t.

    2010-01-01

    The development of a new ultrasonic measurement technique to assess quantitatively wire crimp terminations is discussed. The amplitude change of a compressional ultrasonic wave propagating at right angles to the wire axis and through the junction of a crimp termination is shown to correlate with the results of a destructive pull test, which is a standard for assessing crimp wire junction quality. To demonstrate the technique, the case of incomplete compression of crimped connections is ultrasonically tested, and the results are correlated with pull tests. Results show that the nondestructive ultrasonic measurement technique consistently predicts good crimps when the ultrasonic transmission is above a certain threshold amplitude level. A quantitative measure of the quality of the crimped connection based on the ultrasonic energy transmitted is shown to respond accurately to crimp quality. A wave propagation model, solved by finite element analysis, describes the compressional ultrasonic wave propagation through the junction during the crimping process. This model is in agreement within 6% of the ultrasonic measurements. A prototype instrument for applying this technique while wire crimps are installed is also presented. The instrument is based on a two-jaw type crimp tool suitable for butt-splice type connections. A comparison of the results of two different instruments is presented and shows reproducibility between instruments within a 95% confidence bound.

  7. Survey of Processing Methods for High Strength High Conductivity Wires for High Field Magnet Applications

    Energy Technology Data Exchange (ETDEWEB)

    Han, K.; Embury, J.D.

    1998-10-01

    This paper will deal with the basic concepts of attaining combination of high strength and high conductivity in pure materials, in-situ composites and macrocomposites. It will survey current attainments, and outline where some future developments may lie in developing wire products that are close to the theoretical strength of future magnet applications.

  8. Test methods and response surface models for hot, humid air decontamination of materials contaminated with dirty spores of Bacillus anthracis ∆Sterne and Bacillus thuringiensis Al Hakam.

    Science.gov (United States)

    Buhr, T L; Young, A A; Barnette, H K; Minter, Z A; Kennihan, N L; Johnson, C A; Bohmke, M D; DePaola, M; Cora-Laó, M; Page, M A

    2015-11-01

    To develop test methods and evaluate survival of Bacillus anthracis ∆Sterne or Bacillus thuringiensis Al Hakam on materials contaminated with dirty spore preparations after exposure to hot, humid air using response surface modelling. Spores (>7 log10 ) were mixed with humic acid + spent sporulation medium (organic debris) or kaolin (dirt debris). Spore samples were then dried on five different test materials (wiring insulation, aircraft performance coating, anti-skid, polypropylene, and nylon). Inoculated materials were tested with 19 test combinations of temperature (55, 65, 75°C), relative humidity (70, 80, 90%) and time (1, 2, 3 days). The slowest spore inactivation kinetics was on nylon webbing and/or after addition of organic debris. Hot, humid air effectively decontaminates materials contaminated with dirty Bacillus spore preparations; debris and material interactions create complex decontamination kinetic patterns; and B. thuringiensis Al Hakam is a realistic surrogate for B. anthracis. Response surface models of hot, humid air decontamination were developed which may be used to select decontamination parameters for contamination scenarios including aircraft. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

  9. Wire EDM for Refractory Materials

    Science.gov (United States)

    Zellars, G. R.; Harris, F. E.; Lowell, C. E.; Pollman, W. M.; Rys, V. J.; Wills, R. J.

    1982-01-01

    In an attempt to reduce fabrication time and costs, Wire Electrical Discharge Machine (Wire EDM) method was investigated as tool for fabricating matched blade roots and disk slots. Eight high-strength nickel-base superalloys were used. Computer-controlled Wire EDM technique provided high quality surfaces with excellent dimensional tolerances. Wire EDM method offers potential for substantial reductions in fabrication costs for "hard to machine" alloys and electrically conductive materials in specific high-precision applications.

  10. Wire chamber

    CERN Multimedia

    1967-01-01

    Magnetoscriptive readout wire chamber.Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

  11. Wire Chamber

    CERN Multimedia

    Magnetoscriptive readout wire chamber. Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

  12. Hot-mix asphalt testing for the South African pavement design method

    CSIR Research Space (South Africa)

    Anochie-Boateng, Joseph

    2010-08-01

    Full Text Available of local and international hot-mix asphalt (HMA) test methods and modify or adapt them to suit South African road pavement conditions. This paper presents various laboratory HMA test protocols developed as part of the project to revise SAPDM. Large scale...

  13. Hot-stage microscopy for determination of API fragmentation: comparison with other methods.

    Science.gov (United States)

    Šimek, Michal; Grünwaldová, Veronika; Kratochvíl, Bohumil

    2016-08-01

    Although the fragmentation of the active pharmaceutical ingredient (API) is a phenomenon that is mentioned in many literature sources, no well-suited analytical tools for its investigation are currently known. We used the hot-stage microscopy method, already presented in our previous work, and studied the real fragmentation of the tadalafil particles in model tablets which were prepared under different compaction pressures. The morphology, spectral imaging and evaluation of plastic and elastic energies were also analyzed to support the hot-stage method. The prepared blend of tadalafil and excipients was compacted under a several forces from 5 to 35 kN to reveal the trend of fragmentation. The exact fragmentation of tadalafil with increased compaction pressure was revealed by the hot-stage microscopic method and it was in good agreement with plastic and elastic energies. Conversely, spectral imaging, which is being used for this analysis, was considered to be inaccurate methodology as mainly agglomerates, not individual particles, were measured. The availability of the hot-stage microscopic method equips pharmaceutical scientists with an in vitro assessment technique that will more reliably determine the fragmentation of the API in finished tablets and the behavior of the particles when compacted.

  14. MRT letter: In situ observation method for microstructural changes of steel during hot deformation.

    Science.gov (United States)

    Yogo, Yasuhiro; Takeuchi, Hirohisa; Tanaka, Kouji; Iwata, Noritoshi; Nakanishi, Koukichi; Ishikawa, Takashi

    2009-12-01

    We report on the result of an in situ method for observing microstructural changes during hot deformation. The observation of microstructural changes of steel at 1,473 K under tensile strain is demonstrated using the reported method. The development of deformed structures and the formation of a new grain boundary, which subsequently moved with increased strain, were clearly observed. The effectiveness of this method was confirmed by the results of several examples.

  15. wire chamber

    CERN Multimedia

    Proportional multi-wire chamber. Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle. Proportional wire chambers allow a much quicker reading than the optical or magnetoscriptive readout wire chambers.

  16. An assumed mode method and finite element method investigation of the coupled vibration in a flexible-disk rotor system with lacing wires

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Shui-Ting; Huang, Hong-Wu [Hunan University, Changsha (China); Chiu, Yi-Jui; Yu, Guo-Fei [Xiamen University of Technology, Xiamen (China); Yang, Chia-Hao [Taipei Chengshih University of Science and Technology, Taipei (China); Jian, Sheng-Rui [I-Shou University, Kaohsiung (China)

    2017-02-15

    The Assumed mode method (AMM) and Finite element method (FEM) were used. Their results were compared to investigate the coupled shaft-torsion, disk-transverse, and blade-bending vibrations in a flexible-disk rotor system. The blades were grouped with a spring. The flexible-disk rotor system was divided into three modes of coupled vibrations: Shaft-disk-blade, disk-blade, and blade-blade. Two new modes of coupled vibrations were introduced, namely, lacing wires-blade and lacing wires-disk-blade. The patterns of change of the natural frequencies and mode shapes of the system were discussed. The results showed the following: first, mode shapes and natural frequencies varied, and the results of the AMM and FEM differed; second, numerical calculation results showed three influencing factors on natural frequencies, namely, the lacing wire constant, the lacing wire location, and the flexible disk; lastly, the flexible disk could affect the stability of the system as reflected in the effect of the rotational speed.

  17. Optimization of Wire Electrical Discharge Machining Process Using Taguchi Method and Back Propagation Neural Network

    OpenAIRE

    SAĞBAŞ, Aysun; KAHRAMAN, Funda; Esme, Uğur

    2017-01-01

    In this study, it isattempted to model and optimize the wire electrical discharge machining (WEDM)process using Taguchi design of experiment and artificial neural network. Aneural network with back propagation algorithm was developed to predict theperformance characteristic, namely surface roughness. An approach to determineoptimal machining parameters setting was proposed based on the Taguchi designmethod. In addition, analysis of variance (ANOVA) was performed to identify thesignificant par...

  18. Percutaneous Kirschner wire (K-wire) fixation for humerus shaft ...

    African Journals Online (AJOL)

    In the present study, Kirschner wires (K-wire) were used to achieve a closed intramedullary fixation of humeral shaft fractures. The objective of this study was to evaluate the efficacy of intramedullary K-wires for the treatment of humeral shaft fracture in children. Patients and Methods: This prospective study was conducted in ...

  19. Application of ZnO single-crystal wire grown by the thermal evaporation method as a chemical gas sensor for hydrogen sulfide.

    Science.gov (United States)

    Park, N K; Lee, S Y; Lee, T J

    2011-01-01

    A zinc oxide single-crystal wire was synthesized for application as a gas-sensing material for hydrogen sulfide, and its gas-sensing properties were investigated in this study. The gas sensor consisted of a ZnO thin film as the buffer layer and a ZnO single-crystal wire. The ZnO thin film was deposited over a patterning silicon substrate with a gold electrode by the CFR method. The ZnO single-crystal wire was synthesized over the ZnO thin film using zinc and activated carbon as the precursor for the thermal evaporation method at 800 degrees C. The electrical properties of the gas sensors that were prepared for the growth of ZnO single-crystal wire varied with the amount of zinc contained in the precursor. The charged current on the gas sensors increased with the increasing amount of zinc in the precursor. It was concluded that the charged current on the gas sensors was related to ZnO single-crystal wire growth on the silicon substrate area between the two electrodes. The charged current on the gas sensor was enhanced when the ZnO single-crystal wire was exposed to a H2S stream. The experimental results obtained in this study confirmed that a ZnO single-crystal wire can be used as a gas sensor for H2S.

  20. Modeling of radio-frequency induced currents on lead wires during MR imaging using a modified transmission line method.

    Science.gov (United States)

    Acikel, Volkan; Atalar, Ergin

    2011-12-01

    Metallic implants may cause serious tissue heating during magnetic resonance (MR) imaging. This heating occurs due to the induced currents caused by the radio-frequency (RF) field. Much work has been done to date to understand the relationship between the RF field and the induced currents. Most of these studies, however, were based purely on experimental or numerical methods. This study has three main purposes: (1) to define the RF heating properties of an implant lead using two parameters; (2) to develop an analytical formulation that directly explains the relationship between RF fields and induced currents; and (3) to form a basis for analysis of complex cases. In this study, a lumped element model of the transmission line was modified to model leads of implants inside the body. Using this model, leads are defined using two parameters: impedance per unit length, Z, and effective wavenumber along the lead, k(t). These two parameters were obtained by using methods that are similar to the transmission line theory. As long as these parameters are known for a lead, currents induced in the lead can be obtained no matter how complex the lead geometry is. The currents induced in bare wire, lossy wire, and insulated wire were calculated using this new method which is called the modified transmission line method or MoTLiM. First, the calculated induced currents under uniform electric field distribution were solved and compared with method-of-moments (MoM) calculations. In addition, MoTLiM results were compared with those of phantom experiments. For experimental verification, the flip angle distortion due to the induced currents was used. The flip angle distribution around a wire was both measured by using flip angle imaging methods and calculated using current distribution obtained from the MoTLiM. Finally, these results were compared and an error analysis was carried out. Bare perfect electric, bare lossy, and insulated perfect electric conductor wires under uniform and

  1. Safe trapping of cesium into pollucite structure by hot-pressing method

    Energy Technology Data Exchange (ETDEWEB)

    Omerašević, Mia, E-mail: mia@vinca.rs [University of Belgrade, Institute of Nuclear Sciences “Vinča”, Materials Department, PO Box 522, 11001 Belgrade (Serbia); Matović, Ljiljana; Ružić, Jovana [University of Belgrade, Institute of Nuclear Sciences “Vinča”, Materials Department, PO Box 522, 11001 Belgrade (Serbia); Golubović, Željko [First Quantum Minerals Ltd., 543 Granville Street, Vancouver, British Colombia, V6C 1X8 (Canada); Jovanović, Uroš [University of Belgrade, Institute of Nuclear Sciences “Vinča”, Chemical Dynamics Laboratory, P.O. Box 522, 11001 Belgrade (Serbia); Mentus, Slavko; Dondur, Vera [University of Belgrade, Faculty of Physical Chemistry, Studentski trg 12-16, 11000 Belgrade (Serbia)

    2016-06-15

    A simple one-step method with direct thermal conversion at lower temperatures for preparing a stabile Cs-aluminsilicate phase, known as pollucite, is presented. Cs-exchanged form of Na, Ca-LTA type of zeolite (Cs-LTA) was pressureless sintered and hot pressed at certain temperatures in order to obtain pollucite. XRD and FTIR analysis were used to study structural changes of Cs-LTA before and after thermal treatments. Pressureless sintered sample recrystallized into pollucite phase after heat treatment at 1000 °C (3 h) (PLS1000) and hot pressed sample at 750 °C (3 h) using pressure of 35 MPa (HP750), indicating reduced temperature of 250°. SEM micrographs confirmed that HP750 has higher density than PLS1000 which leads to higher value of compressive strength. The HP750 showed better resistance to Cs leaching than the PLS1000. Base on these results one can conclude that hot pressing is the promising method for the permanent disposal of Cs radionuclides. - Highlights: • Na, Ca-LTA zeolite showed high affinity for Cs ions. • Pollucite phase was obtained using hot pressing at temperature as low as ​750 °C. • HP750 shows better mechanical and morphological properties than PLS1000. • HP750 has lower leaching rate of Cs ions than PLS1000.

  2. Damage detection methods on wind turbine blade testing with wired and wireless accelerometer sensors

    DEFF Research Database (Denmark)

    Mollineaux, Mark; Balafas, Konstantinos; Branner, Kim

    2014-01-01

    Testing   was   performed   on   a   34   meter   blade   at   a   facility   in   DTU   Risø   Campus, featuring   both   wired   accelerometers   and   low­power   MEMs­based   wireless accelerometers. Testing was focused on an induced delamination area on the trailing edge of the blade, which ...

  3. wire chamber

    CERN Multimedia

    Was used in ISR (Intersecting Storage Ring) split field magnet experiment. Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

  4. wire chamber

    CERN Multimedia

    1985-01-01

    Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

  5. wire chamber

    CERN Multimedia

    Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

  6. Wire chamber

    CERN Multimedia

    Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

  7. Electrochemical properties of Sn-based nanopowders synthesized by a pulsed wire evaporation method and effect of binder coating

    Energy Technology Data Exchange (ETDEWEB)

    Ha, Jong-Keun [School of Materials Science and Engineering & RIGET, Gyeongsang National University, 501, Jinju-daero, Jinju-si, Gyeongsangnam-do (Korea, Republic of); Song, Ju-Seok; Cho, Gyu-Bong; Ahn, Jou-Hyeon [Dept. of Materials Engineering and Convergence Technology & RIGET, Gyeongsang National University, 501, Jinju-daero, Jinju-si, Gyeongsangnam-do (Korea, Republic of); Ahn, Hyo-Jun, E-mail: ahj@gnu.ac.kr [School of Materials Science and Engineering & RIGET, Gyeongsang National University, 501, Jinju-daero, Jinju-si, Gyeongsangnam-do (Korea, Republic of); Dept. of Materials Engineering and Convergence Technology & RIGET, Gyeongsang National University, 501, Jinju-daero, Jinju-si, Gyeongsangnam-do (Korea, Republic of); Cho, Kwon-Koo, E-mail: kkcho66@gnu.ac.kr [School of Materials Science and Engineering & RIGET, Gyeongsang National University, 501, Jinju-daero, Jinju-si, Gyeongsangnam-do (Korea, Republic of); Dept. of Materials Engineering and Convergence Technology & RIGET, Gyeongsang National University, 501, Jinju-daero, Jinju-si, Gyeongsangnam-do (Korea, Republic of)

    2016-10-15

    Highlights: • Sn-based nanoparticles are fabricated by using the pulsed wire evaporation method. • The electrodes are prepared by mixing the graphene and coating the surface. • Coating the surface of electrode is used with brushing of simple and facile method. • The electrochemical measurements are performed with galvanostatic experiments. • The coating electrode maintains capacity nearly of 501 mAh g{sup −1} up to 100 cycles. - Abstract: Sn-based nanoparticles are prepared with the O{sub 2} concentrations in chamber of Ar atmosphere (by v/v) by using the pulsed wire evaporation (PWE) method. The prepared electrodes are only Sn-based powder electrode, its binder coating electrode and Sn-based powder/graphene nanocomposite electrode. Morphology and structure of the synthesized powders and electrodes are investigated with a field emission scanning electron microscope (FE-SEM) and an X-ray diffraction (XRD) analysis. The electrochemical measurements were performed with galvanostatic cycling experiments using a coin type cell of CR2032 (Ø20, T3.2 mm). The binder coating electrode is superior to others and maintains delithiation capacity nearly of 501 mAh g{sup −1} as 58.3% of first delithiation capacity at 0.2 C-rate up to 100 cycles.

  8. Experimental verification of a method for estimating energy for domestic hot water production in a 2-stage district heating substation

    Energy Technology Data Exchange (ETDEWEB)

    Yliniemi, Kimmo; Delsing, Jerker; van Deventer, Jan [Luleaa University of Technology, Department of Computer Science and Electrical Engineering, Division EISLAB, 971 87 Luleaa (Sweden)

    2009-02-15

    In this paper we compare our estimate of energy consumption for domestic hot water production in a building with the measured value. The energy consumption for hot water production is estimated from the measured total power consumption. The estimation method was developed using computer simulations, and it is based on the assumption that hot water production causes rapid and detectable changes in power consumption. A comparison of our estimates with measurements indicates that the uncertainty in estimation of hot water energy consumption is {+-}10%. Thus, the estimate is comparable to class 3 energy meter measurements, which have an uncertainty of {+-}2-10%. (author)

  9. Development of scientific and technological basis for the fabrication of thin film solar cells on the basis of a-Si:H and {mu}c-Si:H using the 'hot-wire' deposition technique. Final report; Entwicklung wissenschaftlicher und technischer Grundlagen fuer die Herstellung von Duennschichtsolarzellen auf der Basis des a-Si:H und {mu}c-Si:H mit der 'Hot-Wire'-Depositionstechnik. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, B.

    2002-01-22

    Two new deposition systems were realized enabling the entire and respectively, large area deposition of a-Si:H based solar cells using the so called 'hot-wire' (HW) CVD. The deposition conditions for appropriate n- and p-doped a-Si:H and {mu}c-Si:H layers have been developed. For the first time in the world a-Si:H based pin solar cells were entirely deposited by the HWCVD method. A maximum initial conversion efficiency of {eta}{sub initial}=8.9% was obtained. After the development of a suitable p/n-tunnel/recombination junction pin-pin tandem structures with a-Si:H absorbers could be entirely fabricated by the HWCVD for the first time in the world, too. A conversion efficiency of {eta}=7% was measured for the tandem cell, after some structural degradation took place. In general, the stability of the HWCVD solar cells is not satisfactory, what could be attributed to a structural instability of the HWCVD-p-layers. For the first time we have deposited nip solar cells on stainless steel substrates entirely by HWCVD ({eta}{sub initial}>6%). The incorporation of {mu}c-Si:H absorber layers by HWCVD or ECWR-PECVD into pin solar cells was not successfull until now. Large area deposition of a-Si:H films has been performed in a simple vacuum vessel. Under consideration of appropriate filament and gas supply geometry as well as simulation calculations a good electronic quality and a film thickness uniformity of {delta}d={+-}2.5% of the material was obtained. i-layers for small area solar cells on an area of 20 x 20 cm{sup 2} have been deposited which could be completed to solar cells with very uniform conversion efficiencies of {eta}{sub initial} = 6,1{+-}0.2%. This result represents a proof of concept for the large area deposition of a-Si:H based solar cells using the HWCVD. Also for the first time the HWCVD was used for the deposition of emitter layers on c-Si-wafers to realize hetero solar cells. Hetero solar cells with amorphous, microcrystalline and epitaxial n

  10. A hybrid surface modification method on copper wire braids for enhancing thermal performance of ultra-thin heat pipes

    Science.gov (United States)

    Sheng, W. K.; Lin, H. T.; Wu, C. H.; Kuo, L. S.; Chen, P. H.

    2017-02-01

    Copper is the most widely used material in heat pipe manufacturing. Since the capability of wick structures inside a heat pipe will dominate its thermal performance, in this study, we introduce a hybrid surface modification method on the copper wire braids being inserted as wick structure into an ultra-thin heat pipe. The hybrid method is the combination of a chemical-oxidation-based method and a sol-gel method with nanoparticles being dip-coated onto the braid. The experimental data show that braids under hybrid treatment perform higher water rising speed than the oxidized braids while owning higher water net weight than those braids being only dip-coated with nanoparticle.

  11. Quantification of Residual Stresses in Hot Rolled Steel Sheets by the Hole Drilling Method

    Directory of Open Access Journals (Sweden)

    Trebuňa, F.

    2007-01-01

    Full Text Available The paper deals with the problems of quantification of residual stresses in hot rolled sheets produced under various regimes. On the base of stress distribution along width and thickness of the belt is pointed out on possibilities of belt deformation from the plane as a result of action of torsional moment as an integral internal quantity in cross-section. For the non-uniformly distributed stresses along the thickness of the sheet the new method for residual stresses determination was developed. Application of the method is described in the paper.

  12. Extended First-Principles Molecular Dynamics Method From Cold Materials to Hot Dense Plasmas

    CERN Document Server

    Zhang, Shen; Kang, Wei; Zhang, Ping; He, Xian-Tu

    2016-01-01

    An extended first-principles molecular dynamics (FPMD) method based on Kohn-Sham scheme is proposed to elevate the temperature limit of the FPMD method in the calculation of dense plasmas. The extended method treats the wave functions of high energy electrons as plane waves analytically, and thus expands the application of the FPMD method to the region of hot dense plasmas without suffering from the formidable computational costs. In addition, the extended method inherits the high accuracy of the Kohn-Sham scheme and keeps the information of elec- tronic structures. This gives an edge to the extended method in the calculation of the lowering of ionization potential, X-ray absorption/emission spectra, opacity, and high-Z dense plasmas, which are of particular interest to astrophysics, inertial confinement fusion engineering, and laboratory astrophysics.

  13. The Terminal Responses of the Two-Wire Line in Multiaperture Cavities Based on Electromagnetic Topology and Method of Moments

    Directory of Open Access Journals (Sweden)

    Ying Li

    2011-01-01

    Full Text Available A simulation technique based on electromagnetic topology (EMT theory is proposed for analyzing electromagnetic interference (EMI coupling through apertures onto the two-transmission line enclosed within metallic structures. The electromagnetic interactions between apertures and the external-internal interactions were treated through the topological decomposition and the multistep iterative method. Then, the load responses of the two-wire transmission line are resolved by the the Baum-Liu-Tesche (BLT equation. The simulation results both without and with the electromagnetic interaction are presented for the frequency range from 100 MHz to 3 GHz. These numerical results obtained by two methods imply that the electromagnetic interaction cannot be simply ignored, especially for the frequency range up to 1 GHz.

  14. Virtual method for the determination of an optimum thermal design of hot stamping tools

    Science.gov (United States)

    Weiß, W.; Koplenig, M.; Alb, M.; Graf, J.

    2016-11-01

    This work presents a new virtual method for the optimised thermal design of hot stamping tools. It provides optimal positions of the tool's tempering ducts with respect to the average working temperature and its homogeneous distribution on the surface of a tool. It consists of a specific procedure for hot stamping tool design and a software framework in order to interconnect three domains: (I) a parametrised CAD tool model, (II) a linear thermal solver using a fast boundary element method and (III) an optimisation algorithm. This enables the automated set-up, simulation and optimisation of a duct topology. The boundary conditions for the simulations are derived from a reduced model of the thermal loading of the tool. The virtual method proposed is demonstrated on simplified tool segment geometries. The results are transferred to complex tool designs used in industry. For a selected use case, the number of ducts could be reduced by 50% through the application of the proposed method. These results are validated virtually based on an existing design. Hence, the new virtual method contributes to a CAE-driven tool design and a more efficient tool manufacturing.

  15. Electrochemical properties of Sn/C nanoparticles fabricated by redox treatment and pulsed wire evaporation method

    Science.gov (United States)

    Song, Ju-Seok; Cho, Gyu-Bong; Ahn, Jou-Hyeon; Cho, Kwon-Koo

    2017-09-01

    Tin (Sn) based anode materials are the most promising anode materials for lithium-ion batteries due to their high theoretical capacity corresponding to the formation of Li4.4Sn composition (Li4.4Sn, 994 mAh/g). However, the applications of tin based anodes to lithium-ion battery system are generally limited by a large volume change (>260%) during lithiation and delithiation cycle, which causes pulverize and poor cycling stability. In order to overcome this shortcoming, we fabricate a Sn/C nanoparticle with a yolk-shell structure (Sn/void/C) by using pulsed wire evaporation process and oxidation/reduction heat treatment. Sn nanoparticles are encapsulated by a conductive carbon layer with structural buffer that leaves enough room for expansion and contraction during lithium insertion/desertion. We expect that the yolk-shell structure has the ability to accommodate the volume changes of tin and leading to an improved cycle performance. The Sn/Void/C anode with yolk-shell structure shows a high specific capacity of 760 mAh/g after 50 cycles.

  16. Synthesis and characterization of diamond microcrystals and nanorods deposited by hot cathode direct current plasma chemical vapor deposition method

    NARCIS (Netherlands)

    Zeng, L.; Peng, H.; Wang, W.; Chen, Y.; Lei, D.; Qi, W.; Liang, J.; Zhao, J.; Kong, X.; Zhang, H.

    2008-01-01

    (111) diamond microcrystals and (100) diamond microcrystals and nanorods were synthesized on Si substrate by hot cathode direct current plasma chemical vapor deposition method. The morphology, structure, and optical properties of the diamond films were characterized by scanning electron microscopy,

  17. Standard Test Method for Hot Spot Protection Testing of Photovoltaic Modules

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 This test method provides a procedure to determine the ability of a photovoltaic (PV) module to endure the long-term effects of periodic “hot spot” heating associated with common fault conditions such as severely cracked or mismatched cells, single-point open circuit failures (for example, interconnect failures), partial (or non-uniform) shadowing or soiling. Such effects typically include solder melting or deterioration of the encapsulation, but in severe cases could progress to combustion of the PV module and surrounding materials. 1.2 There are two ways that cells can cause a hot spot problem; either by having a high resistance so that there is a large resistance in the circuit, or by having a low resistance area (shunt) such that there is a high-current flow in a localized region. This test method selects cells of both types to be stressed. 1.3 This test method does not establish pass or fail levels. The determination of acceptable or unacceptable results is beyond the scope of this test method....

  18. Método de fio quente na determinação das propriedades térmicas de polímeros Hot wire technique in the determination of thermal properties of polymers

    Directory of Open Access Journals (Sweden)

    Wilson N. dos Santos

    2004-12-01

    Full Text Available A técnica de fio quente paralelo normalizada para a determinação da condutividade térmica de materiais cerâmicos foi empregada na determinação das propriedades térmicas de polímeros. As amostras foram preparadas em forma de paralelepípedos retangulares, com dimensões de (230x80x30mm. Neste trabalho, a condutividade térmica e o calor específico foram simultaneamente determinados a partir do mesmo transiente térmico experimental e a difusividade térmica foi calculada a partir dessas duas propriedades. Cinco diferentes polímeros com diferentes estruturas a temperatura ambiente foram selecionados neste trabalho. Os cálculos foram feitos utilizando-se um método de ajuste por regressão não linear, de tal maneira que todos os pontos experimentais obtidos são considerados nos cálculos dessas propriedades térmicas. O equipamento utilizado neste trabalho é totalmente automatizado. A reprodutibilidade dos resultados foi muito boa com respeito à condutividade térmica, obtendo-se um desvio máximo de apenas 0,5% entre os valores máximo e mínimo para todas as amostras ensaiadas, mesmo introduzindo propositadamente alguns defeitos no arranjo experimental, em relação ao modelo teórico. Todavia, pequenos desvios do modelo teórico podem causar drásticas influências nos valores de calor específico, obtendo-se desvios de até 32% em relação ao arranjo experimental correto. Os resultados experimentais foram então comparados com aqueles encontrados na literatura. As discrepâncias observadas entre alguns desses valores podem estar associadas ao grau de cristalinidade ou à história térmica da amostra, ficando assim mostrada a aplicabilidade desta técnica na determinação das propriedades térmicas de polímeros.The hot wire parallel technique standardized for determining thermal conductivity of ceramic materials was employed in the determination of thermal properties of polymers. Samples were prepared in shape of rectangular

  19. Insulation effect on thermal stability of Coated Conductors wires in liquid nitrogen

    Science.gov (United States)

    Rubeli, Thomas; Dutoit, Bertrand; Martynova, Irina; Makarevich, Artem; Molodyk, Alexander; Samoilenkov, Sergey

    2017-02-01

    Superconducting wires are not perfectly homogeneous in term of critical current as well as stabilization. In resistive fault current limiter applications this could lead to hot spots if the fault current is only slightly above the nominal current of the device. Increasing stabilization by using thicker silver coating for example may prevent this problem but this method implies longer wire length to maintain the same impedance during a fault. Very efficient cooling in another way to prevent hot spots, this can be achieved in nucleate boiling regime. Optimal insulation can be used to prevent film boiling regime, staying in nucleate boiling regime in a much broader temperature range. In this work a novel technique is used to monitor in real time the temperature of the wire during the quench. Using this method several increasing insulation thicknesses are tested, measuring for each the heat exchange rate to the nitrogen bath. Exchange rate measurements are made in quasistatic regime and during the re-cooling of the wire. SuperOx wires provided with different insulation thicknesses exhibit an excellent stability, far above a bare wire. On the other side, for very thick insulations the stability gain is lost. Re-cooling speeds dependency on insulation thicknesses is measured too.

  20. Dry hot air: is it a reliable method of disinfection for urological endoscopes? Preliminary study.

    Science.gov (United States)

    Abdel-Kader, Mohammad S; Abdel-Maguid, Ali M

    2009-09-01

    To evaluate dry hot air effect as a reliable method of disinfection of urological endoscopes. Two groups of urological endoscopic instruments (2 cystoscopic sheaths, 2 bridges, and 2 working elements of resectoscope and urethrotome for each group), after being sterilized by full immersion in 2% glutaraldehyde solution for 10 hours, were contaminated by immersion in suspensions of Staphylococcus saprophyticus (3 x 10(3) CFU/mL), Escherichia coli (28 x 10(2) CFU/mL), and Candida albicans (27 x 10(2) CFU/mL). Group I was exposed to disinfection by full immersion in 2% glutaraldehyde solution for 20 minutes. Group II was exposed to dry hot air obtained by using a hair dryer for 3 minutes. The surfaces and lumens of the instruments of both groups were washed with specific volumes of saline. The surface and luminal specimens were collected separately and used for culture on different media specific for these organisms. Colony-forming units were estimated. In group I, the cultures isolated from the instrument surface washes were negative but those isolated from the luminal injected saline were all positive for S. saprophyticus (60 CFU/mL), E. coli (50 CFU/mL), and C. albicans (50 CFU/mL). In group II, the cultures isolated from both the instrument surface and luminal saline washes were negative for all 3 above-mentioned microorganisms. Hot dry air by using a hair dryer is an inexpensive, rapid, easy, easily available, and effective method of disinfection compared with glutaraldehyde solution.

  1. Time resolved investigations on flow field and quasi wall shear stress of an impingement configuration with pulsating jets by means of high speed PIV and a surface hot wire array

    Energy Technology Data Exchange (ETDEWEB)

    Janetzke, Timm [Berlin Institute of Technology, Department of Aeronautics and Astronautics, Chair of Aerodynamics, Marchstr. 12, 10587 Berlin (Germany)], E-mail: Timm.Janetzke@ILR.TU-Berlin.de; Nitsche, Wolfgang [Berlin Institute of Technology, Department of Aeronautics and Astronautics, Chair of Aerodynamics, Marchstr. 12, 10587 Berlin (Germany)

    2009-10-15

    The effects of jet pulsation on flow field and quasi wall shear stress of an impingement configuration were investigated experimentally. The excitation Strouhal number and amplitude were varied as the most influential parameters. A line-array with three submerged air jets, and a confining plate were used. The flow field analysis by means of time resolved particle image velocimetry shows that the controlled excitation can considerably affect the near-field flow of an impinging jet array. These effects are visualized as organization of the coherent flow structures. Augmentation of the Kelvin-Helmholtz vortices in the jet shear layer depends on the Strouhal number and pulsation magnitude and can be associated with pairing of small scale vortices in the jet. A total maximum of vortex strength was observed when exciting with Sr = 0.82 and coincident high amplitudes. Time resolved interaction between impinging vortices and impingement plate boundary layer due to jet excitation was verified by using an array of 5 {mu}m surface hot wires. Corresponding to the global flow field modification due to periodic jet pulsation, the impact of the vortex rings on the wall boundary layer is highly influenced by the above mentioned excitation parameters and reaches a maximum at Sr = 0.82.

  2. Automated nondestructive evaluation method for characterizing ceramic and metallic hot gas filters.

    Energy Technology Data Exchange (ETDEWEB)

    Ellingson, W. A.; Koehl, E. R.; Deemer, C.; Pastilla, P.; Wheeler, B.; Forster, G. A.

    2002-06-03

    In advanced coal-fired power generation, one technology under development to clean up hot gases before their use as fuel for gas turbines is rigid ceramic candle filters. These porous filters are typically 1.5 m long and 60 mm in diameter and are made of various ceramic materials, including clay-bonded SiC. The high costs of downtime in a large utility demands that nondestructive evaluation/characterization (NDE/C) methods be available. At shutdowns, data from such analysis are needed to decide which filters are still usable and which need to be replaced, and if possible, to estimate the remaining lifetimes. Thus our objective was to develop reliable low-cost NDE technology for these filters. Our approach was to develop NDE/C technology, referred to as acousto-ultrasonics (AU), for application to hot gas filters. Lamb waves generated by the AU method were analyzed to derive a stress wave factor (SWF). This technology was tested by comparing SWF data with the measured strength for a variety of rigid ceramic filters and was shown to work on iron-aluminide filters as well but no strength data have been obtained on the iron-aluminides at this time.

  3. Measuring convective heat transfer coefficients of nanofluids over a circular fine wire maintaining a constant temperature

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Shinpyo [Kyonggi Univ., Suwon (Korea, Republic of)

    2012-01-15

    This paper describes a measuring apparatus that can be used to appraise the effectiveness of nanofluids as new heat transfer enhancing fluids. A couple of apparatuses using fine hot wires as sensors have been proposed for this purpose; however, they have a technical weakness related to the uncertain working conditions of the sensor. The present method used the convective heat transfer coefficient from a hot wire as an indication of the heat transfer effectiveness of the nanofluid, where the temperature of the wire remains constant during the experiment. The operating principle and experimental procedure are explained in detail, and the validity of the system is tested with pure base fluids. The effects of particle concentration, velocity, and temperature on the heat transfer coefficients of the nanofluids are discussed comprehensively using the experimental data for graphite nanolubrication oil.

  4. Method of locating ground faults

    Science.gov (United States)

    Patterson, Richard L. (Inventor); Rose, Allen H. (Inventor); Cull, Ronald C. (Inventor)

    1994-01-01

    The present invention discloses a method of detecting and locating current imbalances such as ground faults in multiwire systems using the Faraday effect. As an example, for 2-wire or 3-wire (1 ground wire) electrical systems, light is transmitted along an optical path which is exposed to magnetic fields produced by currents flowing in the hot and neutral wires. The rotations produced by these two magnetic fields cancel each other, therefore light on the optical path does not read the effect of either. However, when a ground fault occurs, the optical path is exposed to a net Faraday effect rotation due to the current imbalance thereby exposing the ground fault.

  5. KFC2: a knowledge-based hot spot prediction method based on interface solvation, atomic density, and plasticity features.

    Science.gov (United States)

    Zhu, Xiaolei; Mitchell, Julie C

    2011-09-01

    Hot spots constitute a small fraction of protein-protein interface residues, yet they account for a large fraction of the binding affinity. Based on our previous method (KFC), we present two new methods (KFC2a and KFC2b) that outperform other methods at hot spot prediction. A number of improvements were made in developing these new methods. First, we created a training data set that contained a similar number of hot spot and non-hot spot residues. In addition, we generated 47 different features, and different numbers of features were used to train the models to avoid over-fitting. Finally, two feature combinations were selected: One (used in KFC2a) is composed of eight features that are mainly related to solvent accessible surface area and local plasticity; the other (KFC2b) is composed of seven features, only two of which are identical to those used in KFC2a. The two models were built using support vector machines (SVM). The two KFC2 models were then tested on a mixed independent test set, and compared with other methods such as Robetta, FOLDEF, HotPoint, MINERVA, and KFC. KFC2a showed the highest predictive accuracy for hot spot residues (True Positive Rate: TPR = 0.85); however, the false positive rate was somewhat higher than for other models. KFC2b showed the best predictive accuracy for hot spot residues (True Positive Rate: TPR = 0.62) among all methods other than KFC2a, and the False Positive Rate (FPR = 0.15) was comparable with other highly predictive methods. Copyright © 2011 Wiley-Liss, Inc.

  6. STATISTIC MODELING OF DRYING KINETHIC OF SPINACH LEAVES USING MICROWAVE AND HOT AIR METHODS

    Directory of Open Access Journals (Sweden)

    Mojtaba Nouri

    2015-06-01

    Full Text Available The target of this study was to model of spinach leaves drying using microwave and hot air dryer. This test performed in combination treatment of temperatures (50°C, 60°C, and 70°C and microwave (90, 180, 360, 600 and 900w in 3 replications. Sample moisture measured within drying. All the results were fitted and analyzed with 8 mathematical models base on 3 parameters including determination (R2, Chi square(X2, root mean square errors(RSME. Results also revealed that temperature and microwave power effectively reduce the drying time when increase. Drying occurs in degrading stage; moreover the comparison of results exhibited that Page and Two sentences models were fitted appropriately to estimate moisture changing and drying description. Regarding all the results, it is cleared that microwave method is an appropriate method in spinach drying as a result of reducing drying temperature and its high efficiency.

  7. Static Hot Air and Infrared Rays Roasting are Efficient Methods for Aflatoxin Decontamination on Hazelnuts.

    Science.gov (United States)

    Siciliano, Ilenia; Dal Bello, Barbara; Zeppa, Giuseppe; Spadaro, Davide; Gullino, Maria Lodovica

    2017-02-21

    Aflatoxins are a group of secondary metabolites produced by members of Aspergillus Section Flavi that are dangerous to humans and animals. Nuts can be potentially contaminated with aflatoxins, often over the legal threshold. Food processes, including roasting, may have different effects on mycotoxins, and high temperatures have proven to be very effective in the reduction of mycotoxins. In this work, two different roasting methods-traditional static hot air roasting and infra-red rays roasting-were applied and compared for the detoxification of hazelnuts from Italy and Turkey. At the temperature of 140 °C for 40 min of exposure, detoxification was effective for both roasting techniques. Residual aflatoxins after infra-red rays treatments were lower compared to static hot air roasting. On Italian hazelnuts, residual aflatoxins were lower than 5%, while for Turkish hazelnuts they were lower than 15% after 40 min of exposure to an infra-red rays roaster. After roasting, the perisperm was detached from the nuts and analyzed for aflatoxin contents. Residual aflatoxins in the perisperm ranged from 80% up to 100%. After roasting, the lipid profile and the nutritional quality of hazelnuts were not affected. Fatty acid methyl esters analyses showed a similar composition for Italian and Turkish hazelnuts.

  8. A controller design method for 3 phase 4 wire grid connected VSI ...

    Indian Academy of Sciences (India)

    The design method for LCL filter with passive damping by split capacitor configuration has been followed from (Channegowda & John 2010). In the absence of a damping resistor active damping method can also be employed to damp LCL filter resonance (Gabe et al. 2009). The parameters of the power converter and LCL ...

  9. Scalable Nernst thermoelectric power using a coiled galfenol wire

    Directory of Open Access Journals (Sweden)

    Zihao Yang

    2017-09-01

    Full Text Available The Nernst thermopower usually is considered far too weak in most metals for waste heat recovery. However, its transverse orientation gives it an advantage over the Seebeck effect on non-flat surfaces. Here, we experimentally demonstrate the scalable generation of a Nernst voltage in an air-cooled metal wire coiled around a hot cylinder. In this geometry, a radial temperature gradient generates an azimuthal electric field in the coil. A Galfenol (Fe0.85Ga0.15 wire is wrapped around a cartridge heater, and the voltage drop across the wire is measured as a function of axial magnetic field. As expected, the Nernst voltage scales linearly with the length of the wire. Based on heat conduction and fluid dynamic equations, finite-element method is used to calculate the temperature gradient across the Galfenol wire and determine the Nernst coefficient. A giant Nernst coefficient of -2.6 μV/KT at room temperature is estimated, in agreement with measurements on bulk Galfenol. We expect that the giant Nernst effect in Galfenol arises from its magnetostriction, presumably through enhanced magnon-phonon coupling. Our results demonstrate the feasibility of a transverse thermoelectric generator capable of scalable output power from non-flat heat sources.

  10. Scalable Nernst thermoelectric power using a coiled galfenol wire

    Science.gov (United States)

    Yang, Zihao; Codecido, Emilio A.; Marquez, Jason; Zheng, Yuanhua; Heremans, Joseph P.; Myers, Roberto C.

    2017-09-01

    The Nernst thermopower usually is considered far too weak in most metals for waste heat recovery. However, its transverse orientation gives it an advantage over the Seebeck effect on non-flat surfaces. Here, we experimentally demonstrate the scalable generation of a Nernst voltage in an air-cooled metal wire coiled around a hot cylinder. In this geometry, a radial temperature gradient generates an azimuthal electric field in the coil. A Galfenol (Fe0.85Ga0.15) wire is wrapped around a cartridge heater, and the voltage drop across the wire is measured as a function of axial magnetic field. As expected, the Nernst voltage scales linearly with the length of the wire. Based on heat conduction and fluid dynamic equations, finite-element method is used to calculate the temperature gradient across the Galfenol wire and determine the Nernst coefficient. A giant Nernst coefficient of -2.6 μV/KT at room temperature is estimated, in agreement with measurements on bulk Galfenol. We expect that the giant Nernst effect in Galfenol arises from its magnetostriction, presumably through enhanced magnon-phonon coupling. Our results demonstrate the feasibility of a transverse thermoelectric generator capable of scalable output power from non-flat heat sources.

  11. Investigation of lateral-directional aerodynamic parameters identification method for fly-by-wire passenger airliners

    National Research Council Canada - National Science Library

    Wu Zhao Wang Lixin Lin Jiaming Ai Junqiang

    2014-01-01

    ... of its signal energy distribution and airframe frequency response, a new method is proposed for signal type selection, signal parameters design, and the appropriate frequency relationship between the aileron and rudder excitation signals...

  12. Hot Spots Detection of Operating PV Arrays through IR Thermal Image Using Method Based on Curve Fitting of Gray Histogram

    Directory of Open Access Journals (Sweden)

    Jiang Lin

    2016-01-01

    Full Text Available The overall efficiency of PV arrays is affected by hot spots which should be detected and diagnosed by applying responsible monitoring techniques. The method using the IR thermal image to detect hot spots has been studied as a direct, noncontact, nondestructive technique. However, IR thermal images suffer from relatively high stochastic noise and non-uniformity clutter, so the conventional methods of image processing are not effective. The paper proposes a method to detect hotspots based on curve fitting of gray histogram. The result of MATLAB simulation proves the method proposed in the paper is effective to detect the hot spots suppressing the noise generated during the process of image acquisition.

  13. Analysis of Different Positions of Fiber-Reinforced Composite Retainers versus Multistrand Wire Retainers Using the Finite Element Method

    Directory of Open Access Journals (Sweden)

    Arezoo Jahanbin

    2014-01-01

    Full Text Available Background. The aim of this study was to evaluate root displacement of the lower incisors fixed with FRC in different positions versus FSW retainers using the finite element method. Materials and Methods. 3D finite element models were designed for a mandibular anterior segment: Model 1: flexible spiral wire bonded to the lingual teeth surfaces, Model 2: FRC bonded to the upper third of lingual teeth surfaces, and Model 3: FRC bonded to the middle third. FE analysis was performed for three models and then tooth displacements were evaluated. Results. In contrast to lateral incisors and canines, the FSW retainer caused the central teeth to move more than the teeth bonded with FRC in both loadings. Comparison between Models 2 and 3 (in vertical loading showed that FRC retainers that bonded at the upper third of lingual teeth surfaces made central and canine teeth move less than FRC retainers bonded at the middle third; however, for lateral teeth it was the opposite. Conclusion. FRC retainers bonded at the upper third of lingual teeth surfaces make central and canine teeth move less than FRC retainers bonded at the middle third in vertical loading; however, for lateral teeth it was the opposite.

  14. Influence of different brazing and welding methods on tensile strength and microhardness of orthodontic stainless steel wire.

    Science.gov (United States)

    Bock, Jens Johannes; Fraenzel, Wolfgang; Bailly, Jacqueline; Gernhardt, Christian Ralf; Fuhrmann, Robert Andreas Werner

    2008-08-01

    The aim of this study was to compare the mechanical strength and microhardness of joints made by conventional brazing and tungsten inert gas (TIG) and laser welding. A standardized end-to-end joint configuration of the orthodontic wire material in spring hard quality was used. The joints were made using five different methods: brazing (soldering > 450 degrees C) with universal silver solder, two TIG, and two laser welders. Laser parameters and welding conditions were used according to the manufacturers' guidance. The tensile strengths were measured with a universal testing machine (Zwick 005). The microhardness measurements were carried out with a hardness tester (Zwick 3202). Data were analysed using one-way analysis of variance and Bonferroni's post hoc correction (P TIG or laser welding were found. The highest means were observed for TIG welding (699-754 MPa). Laser welding showed a significantly lower mean tensile strength (369-520 MPa) compared with TIG welding. Significant differences (P welded area. The mean microhardness differed significantly between brazing (1.99 GPa), TIG (2.22-2.39 GPa) and laser welding (2.21-2.68 GPa). For orthodontic purposes, laser and TIG welding are solder-free alternatives to joining metal. TIG welding with a lower investment cost is comparable with laser welding. However, while expensive, the laser technique is a sophisticated and simple method.

  15. Use of quality planning methods in optimizing welding wire quality characteristics

    Directory of Open Access Journals (Sweden)

    D. Vykydal

    2013-10-01

    Full Text Available The quality of a product is given by the extent, to which the product meets customer requirements. It is generally accepted that the extent, to which the product meets such customer requirements, and, consequently, the resulting quality of the product itself, substantially depend on the early stages of the product lifecycle, i.e. on the design and development stages. Appropriate means for effective product quality planning can be found among quality management methods and tools. These methods are typically employed in engineering production and automotive industry. This paper focuses on exploring the potential of Quality Function Deployment (QFD and Failure Mode and Effect Analysis (FMEA methods for use in metallurgical production, an industrial branch where they have not been commonly employed as yet.

  16. Fabrication and application of mesoporous TiO{sub 2} film coated on Al wire by sol-gel method with EISA

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Linkang; Lu, Jianjun, E-mail: lujianjunktz@tyut.edu.cn

    2017-04-30

    Highlights: • Successfully fabricated mesoporous TiO{sub 2} thin film on Al wire by sol-gel method with EISA. • Ni supported on this film and exhibits good methanation performance. • Investigate the decomposition temperature of template agent F127 in TiO{sub 2} precursor system. - Abstract: Mesoporous TiO{sub 2} film on Al wire was fabricated by sol-gel method with evaporation induced self assembly (EISA) process using F127 as templating agent in the mixed solution of ethanol and Tetra-n-butyl Titanate. The Ni/TiO{sub 2} film catalyst supported on Al wire was prepared by impregnation and the catalytic performance on methanation was carried out in a titanium alloy micro-reactor tube. It was shown that anatase mesoporous TiO{sub 2} film was prepared in this conditions (1 g F127,calcined at 400 °C and aged for 24 h), which has specific surface area of 127 m{sup 2} g{sup −1} and narrow pore size distribution of 5.3 nm. Low calcined temperature (300 °C) cannot transfer film to anatase and decompose F127 completely. Ni/TiO{sub 2} film on Al wire catalyst was proved to be active in CO methanation reaction. And the CO conversion reaches 99% and CH{sub 4} selectivity close is to 80% when the reaction temperature is higher 360 °C.

  17. Synthesis of γ-WO{sub 3} thin films by hot wire-CVD and investigation of its humidity sensing properties

    Energy Technology Data Exchange (ETDEWEB)

    Jadkar, Vijaya; Waykar, Ravindra; Jadhavar, Ashok [School of Energy Studies, Savitribai Phule Pune University, Pune 411 007 (India); Pawbake, Amit [School of Energy Studies, Savitribai Phule Pune University, Pune 411 007 (India); Physical and Material Chemistry Division, National Chemical Laboratory, Pune 411 008 (India); Date, Abhijit [School of Aerospace, Mechanical and Manufacturing Engineering, RMIT University, Plenty Road, Bundoora, Melbourne VIC 3083 (Australia); Late, Dattatray [Physical and Material Chemistry Division, National Chemical Laboratory, Pune 411 008 (India); Pathan, Habib; Gosavi, Suresh; Jadkar, Sandesh [Department of Physics, Savitribai Phule Pune University, Pune 411 007 (India)

    2017-05-15

    In this study, monoclinic tungsten oxide (γ-WO{sub 3}) have been grown in a single step using HW-CVD method by resistively heating W filaments in a constant O{sub 2} pressure. The formation of γ-WO{sub 3} was confirmed using low angle-XRD and Raman spectroscopy analysis. Low angle-XRD analysis revealed that as-deposited WO{sub 3} film are highly crystalline and the crystallites have preferred orientation along the (002) direction. HRTEM analysis and SAED pattern also show the highly crystalline nature of WO{sub 3} with d spacing of ∝ 0.38 nm, having an orientation along the (002) direction. Surface topography investigated by SEM analysis shows the formation of a uniform and homogeneous cauliflower like morphology throughout the substrate surface without flaws and cracks. A humidity sensing device incorporating WO{sub 3} is also fabricated, which shows a maximum humidity sensitivity factor of ∝ 3954% along with a response time of ∝14 s and a recovery time of ∝25 s. The obtained results demonstrate that it is possible to synthesize WO{sub 3} in a single step by HW-CVD method and to fabricate a humidity sensor by using it. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  18. Prediction of solubilities for ginger bioactive compounds in hot water by the COSMO-RS method

    Science.gov (United States)

    Zaimah Syed Jaapar, Syaripah; Azian Morad, Noor; Iwai, Yoshio

    2013-04-01

    The solubilities in water of four main ginger bioactives, 6-gingerol, 6-shogaol, 8-gingerol and 10-gingerol, were predicted using a conductor-like screening model for real solvent (COSMO-RS) calculations. This study was conducted since no experimental data are available for ginger bioactive solubilities in hot water. The σ-profiles of these selected molecules were calculated using Gaussian software and the solubilities were calculated using the COSMO-RS method. The solubilities of these ginger bioactives were calculated at 50 to 200 °C. In order to validate the accuracy of the COSMO-RS method, the solubilities of five hydrocarbon molecules were calculated using the COSMO-RS method and compared with the experimental data in the literature. The selected hydrocarbon molecules were 3-pentanone, 1-hexanol, benzene, 3-methylphenol and 2-hydroxy-5-methylbenzaldehyde. The calculated results of the hydrocarbon molecules are in good agreement with the data in the literature. These results confirm that the solubilities of ginger bioactives can be predicted using the COSMO-RS method. The solubilities of the ginger bioactives are lower than 0.0001 at temperatures lower than 130 °C. At 130 to 200 °C, the solubilities increase dramatically with the highest being 6-shogaol, which is 0.00037 mole fraction, and the lowest is 10-gingerol, which is 0.000039 mole fraction at 200 °C.

  19. Hot Plate Method with Two Simultaneous Temperature Measurements for Thermal Characterization of Building Materials

    Science.gov (United States)

    Osséni, Sibiath O. G.; Ahouannou, Clément; Sanya, Emile A.; Jannot, Yves

    2017-07-01

    This paper presents a study of the hot plate method with two simultaneous temperature measurements, on the heated and unheated faces of a sample to characterize. The thermal properties of polyvinyl chloride, plaster and laterite were considered to be a representative range of building materials. A 1D quadrupolar model was developed to represent the temperature evolution on the two faces over time. Three-dimensional numerical modeling of a quarter of the testing device with COMSOL software allowed defining the domain of the 1D hypothesis validity. The analysis of estimation possibilities of materials' thermal characteristics, with the developed method, revealed that thermal effusivity can be accurately estimated by using the temperature of the heated face at the beginning of heating. We showed that the simultaneous use of two temperatures enables the estimation of the thermal conductivity with a greater accuracy and over a shorter time interval than using the temperature of the heated face alone. We also demonstrated that under certain conditions (samples with a high ratio of thickness to width) the method with two temperature measurements enabled the estimation of the thermal effusivity and conductivity, while the method with one temperature allowed only the thermal effusivity to be estimated, because of 3D effects. This conclusion was confirmed by experimental results obtained with a mortar sample.

  20. Silicon ingot casting: Heat exchanger method. Multi-wire slicing: Fixed abrasive slicing technique, phase 3

    Science.gov (United States)

    Schmid, F.; Khattak, C. P.

    1979-01-01

    In the area of ingot casting the proof of concept of heat exchanger method (HEM) was established. It was also established that HEM cast silicon yielded solar cell performance comparable to Czochralski grown material. Solar cells with conversion efficiencies of up to 15% were fabricated. It was shown that square cross-section ingots can be cast. In the area of crystal slicing, it was established that silicon can be sliced efficiently with the fixed abrasive slicing technique approach. This concept was carried forward to 10 cm diameter workpiece.

  1. Electric wiring domestic

    CERN Document Server

    Coker, A J

    1992-01-01

    Electric Wiring: Domestic, Tenth Edition, is a clear and reliable guide to the practical aspects of domestic electric wiring. Intended for electrical contractors, installation engineers, wiremen and students, its aim is to provide essential up to date information on modern methods and materials in a simple, clear, and concise manner. The main changes in this edition are those necessary to bring the work into line with the 16th Edition of the Regulations for Electrical Installations issued by the Institution of Electrical Engineers. The book begins by introducing the basic features of domestic

  2. High-order standing spin wave modes in Fe{sub 19}Ni{sub 81} micron wire observed by homodyne method

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, A; Motoi, K; Miyajima, H [Department of Physics, Keio University, Hiyoshi, Yokohama 223-8522 (Japan); Uchiyama, T [Department of Electrical Engineering and Computer, Nagoya University, Chikusaku, Nagoya 464-8603 (Japan); Utsumi, Y, E-mail: yamaguch@phys.keio.ac.jp [Laboratory of Advanced Science and Technology fro Industry, University of Hyogo, Koto, Ako, Hyogo 678-1205 (Japan)

    2011-01-01

    The broadband spin dynamics of patterned ferromagnetic Fe{sub 19}Ni{sub 81} microwire with thickness of 80 nm has been investigated experimentally using broadband rectifying method. The rectifying effect provides a highly sensitive method to detect the high-order perpendicular standing spin wave (PSSW) mode. Present analytical calculation reproduces the observed relation between resonance frequency and applied magnetic field. The effective thickness is explained by the pinning condition of magnetic moment at the surface of the wire.

  3. Technical developments: use of targeting guide wire in left subclavian puncture during percutaneous implantation of port-catheter systems using the catheter tip fixation method

    Energy Technology Data Exchange (ETDEWEB)

    Yamagami, Takuji; Kato, Takeharu; Nakamura, Toshiyuki; Iida, Shigeharu; Tanaka, Osamu; Nishimura, Tsunehiko [Department of Radiology, Kyoto Prefectural University of Medicine, 465 Kajii, Kawaramachi-Hirokoji, Kamigyo, Kyoto 602-8566 (Japan)

    2003-04-01

    Our objective was to evaluate the feasibility and safety of a new method in approaching the access route percutaneously for the implantable port-catheter system for repeated hepatic arterial infusion chemotherapy. Fifteen patients underwent port-catheter system placement via the left subclavian artery with the catheter tip fixed within the gastroduodenal artery with embolic materials and a catheter side hole opening to the common hepatic artery. Before port-catheter placement, the right gastric artery was embolized via the femoral catheter access. Then a 0.035-in. guide wire was inserted from the right femoral artery to the left subclavian artery. The guide wire was left in place during puncture by the needle as an access route for catheter placement. At the time of puncture, the tip of the puncture needle was aimed at the guide wire placed in the subclavian artery beforehand. In all 15 patients the procedure was successfully completed in a reasonable time (mean time 95.0 min, range 50-240 min). Complications occurred in two patients: a transient numbness of the arm in 1 patient and a mild hematoma detected in the subcutaneous pocket in another patient. This experience indicates the possibility of using a targeting guide wire in puncture of the subclavian artery as an access route for catheter placement. (orig.)

  4. Invaders in hot water: a simple decontamination method to prevent the accidental spread of aquatic invasive non-native species.

    Science.gov (United States)

    Anderson, Lucy G; Dunn, Alison M; Rosewarne, Paula J; Stebbing, Paul D

    Watersports equipment can act as a vector for the introduction and spread of invasive non native species (INNS) in freshwater environments. To support advice given to recreational water users under the UK Government's Check Clean Dry biosecurity campaign and ensure its effectiveness at killing a range of aquatic INNS, we conducted a survival experiment on seven INNS which pose a high risk to UK freshwaters. The efficacy of exposure to hot water (45 °C, 15 min) was tested as a method by which waters users could 'clean' their equipment and was compared to drying and a control group (no treatment). Hot water had caused 99 % mortality across all species 1 h after treatment and was more effective than drying at all time points (1 h: χ2 = 117.24, p hot water or drying, 6/7 of these species survived for 16 days, highlighting the importance of good biosecurity practice to reduce the risk of accidental spread. In an additional experiment the minimum lethal temperature and exposure time in hot water to cause 100 % mortality in American signal crayfish (Pacifastacus leniusculus), was determined to be 5 min at 40 °C. Hot water provides a simple, rapid and effective method to clean equipment. We recommend that it is advocated in future biosecurity awareness campaigns.

  5. Hot-wire synthesis of Si nanoparticles

    CSIR Research Space (South Africa)

    Scriba, MR

    2008-01-01

    Full Text Available sccm and with a tungsten filament maintained at 1650ºC. The as-prepared powder varies in colour from yellowish to dark brown and is deposited on all surfaces inside the reaction chamber. The material is a highly porous agglomeration of nanoparticles...

  6. Method to determine full work of fracture from disk shaped compact tension tests on hot-mix asphalt

    CSIR Research Space (South Africa)

    Denneman, E

    2010-08-01

    Full Text Available Fatigue cracking is an important mode of failure in hot-mix asphalt (HMA). As part of the revision of the South African pavement design method (SAPDM) a need was identified to assess the fracture toughness of HMA in terms of fracture energy...

  7. Method of making a continuous ceramic fiber composite hot gas filter

    Science.gov (United States)

    Hill, Charles A.; Wagner, Richard A.; Komoroski, Ronald G.; Gunter, Greg A.; Barringer, Eric A.; Goettler, Richard W.

    1999-01-01

    A ceramic fiber composite structure particularly suitable for use as a hot gas cleanup ceramic fiber composite filter and method of making same from ceramic composite material has a structure which provides for increased strength and toughness in high temperature environments. The ceramic fiber composite structure or filter is made by a process in which a continuous ceramic fiber is intimately surrounded by discontinuous chopped ceramic fibers during manufacture to produce a ceramic fiber composite preform which is then bonded using various ceramic binders. The ceramic fiber composite preform is then fired to create a bond phase at the fiber contact points. Parameters such as fiber tension, spacing, and the relative proportions of the continuous ceramic fiber and chopped ceramic fibers can be varied as the continuous ceramic fiber and chopped ceramic fiber are simultaneously formed on the porous vacuum mandrel to obtain a desired distribution of the continuous ceramic fiber and the chopped ceramic fiber in the ceramic fiber composite structure or filter.

  8. Magneto-plasmonic Au-Coated Co nanoparticles synthesized via hot-injection method

    Science.gov (United States)

    Souza, João B., Jr.; Varanda, Laudemir C.

    2018-02-01

    A synthetic procedure is described for the obtaining of superparamagnetic Co nanoparticles (NPs) via hot-injection method in the presence of sodium borohydride. The Co NPs obtained have an average diameter of 5.3 nm and saturation magnetization of 115 emu g‑1. A modified Langevin equation is fitted to the magnetization curves using a log-normal distribution for the particle diameter and an effective field to account for dipolar interactions. The calculated magnetic diameter of the Co NPs is 0.6 nm smaller than TEM-derived values, implying a magnetic dead layer of 0.3 nm. The magnetic core is coated with Au to prevent oxidation, resulting in water-stable magneto-plasmonic Co/Au core/shell NPs with saturation of 71.6 emu g‑1. The coating adds a localized surface plasmon resonance property with absorbance in the so-called ‘therapeutic window’ (690–900 nm), suitable for biomedical applications. It is suggested that these multifunctional NPs are distinguished as a potential platform for applied and fundamental research.

  9. Effect of the Ignition Method on the Extinction Limit for a Flame Spreading over Electric Wire Insulation

    DEFF Research Database (Denmark)

    Mitsui, Fumiya; Nagachi, Masashi; Citerne, Jean-Marie

    Flame spread experiments with wire insulation were conducted in microgravity (parabolic flights) and in normal gravity to understand the effect of the ignition condition on the Limiting Oxygen Concentration (LOC) for an opposed air flow condition of 100 mm/s (typical flow velocity on ISS). Both t...

  10. A Review on Hot-IP Finding Methods and Its Application in Early DDoS Target Detection

    Directory of Open Access Journals (Sweden)

    Xuan Dau Hoang

    2016-10-01

    Full Text Available On the high-speed connections of the Internet or computer networks, the IP (Internet Protocol packet traffic passing through the network is extremely high, and that makes it difficult for network monitoring and attack detection applications. This paper reviews methods to find the high-occurrence-frequency elements in the data stream and applies the most efficient methods to find Hot-IPs that are high-frequency IP addresses of IP packets passing through the network. Fast finding of Hot-IPs in the IP packet stream can be effectively used in early detection of DDoS (Distributed Denial of Service attack targets and spreading sources of network worms. Research results show that the Count-Min method gives the best overall performance for Hot-IP detection thanks to its low computational complexity, low space requirement and fast processing speed. We also propose an early detection model of DDoS attack targets based on Hot-IP finding, which can be deployed on the target network routers.

  11. Ga N nano wires and nano tubes growth by chemical vapor deposition method at different NH{sub 3} flow rate

    Energy Technology Data Exchange (ETDEWEB)

    Li, P.; Liu, Y.; Meng, X. [Wuhan University, School of Physics and Technology, Key Laboratory of Artificial Micro and Nanostructures of Ministry of Education, Wuhan 430072 (China)

    2016-11-01

    Ga N nano wires and nano tubes have been successfully synthesized via the simple chemical vapor deposition method. NH{sub 3} flow rate was found to be a crucial factor in the synthesis of different type of Ga N which affects the shape and the diameter of generated Ga N nano structures. X-ray diffraction confirms that Ga N nano wires grown on Si(111) substrate under 900 degrees Celsius and with NH{sub 3} flow rate of 50 sc cm presents the preferred orientation growth in the (002) direction. It is beneficial to the growth of nano structure through catalyst annealing. Transmission electron microscopy and scanning electron microscopy were used to measure the size and structures of the samples. (Author)

  12. Correction on the influence of thermal contact resistance in thermal conductivity measurements using the guarded hot plate method

    Directory of Open Access Journals (Sweden)

    Stepanić Nenad

    2009-01-01

    Full Text Available This work considers the influence of finite thermal contact resistances which exist in thermal conductivity measurements of homogeneous and poor thermal conductive materials using the guarded hot plate method. As an example of correction method proposed in this work, different experimental results obtained from a standard reference material sample (with the conductivity of about 1 W/mK have been presented.

  13. The technology of testing the safety of steel wire ropes

    Science.gov (United States)

    Zhang, Xiaochun; Hu, Caiwen

    2005-12-01

    To estimate the security of steel wire rope, the broken wire condition, the capability of the rope to bear weight and the state of stress balance of each wire in the steel wire rope were investigated. The wavelet translation method was applied to analyze the signals of magnetic field leakage from the steel wire rope. The result of the time-frequency analysis of the signals can be used to make certain of he position and the amount of the broken wire. Using the static surveillance method as a basis, a dynamic surveillance method was designed to detect the stress balance of the steel wire rope. This technology makes it possible to check the stress condition of each wire on line. It can be concluded that a wavelet translation analysis and the dynamic surveillance technique are effective methods to detect on line and real-time the broken wire and the stress balance of multistrand wire ropes.

  14. Prediction of hot spot residues at protein-protein interfaces by combining machine learning and energy-based methods

    Directory of Open Access Journals (Sweden)

    Pontil Massimiliano

    2009-10-01

    Full Text Available Abstract Background Alanine scanning mutagenesis is a powerful experimental methodology for investigating the structural and energetic characteristics of protein complexes. Individual amino-acids are systematically mutated to alanine and changes in free energy of binding (ΔΔG measured. Several experiments have shown that protein-protein interactions are critically dependent on just a few residues ("hot spots" at the interface. Hot spots make a dominant contribution to the free energy of binding and if mutated they can disrupt the interaction. As mutagenesis studies require significant experimental efforts, there is a need for accurate and reliable computational methods. Such methods would also add to our understanding of the determinants of affinity and specificity in protein-protein recognition. Results We present a novel computational strategy to identify hot spot residues, given the structure of a complex. We consider the basic energetic terms that contribute to hot spot interactions, i.e. van der Waals potentials, solvation energy, hydrogen bonds and Coulomb electrostatics. We treat them as input features and use machine learning algorithms such as Support Vector Machines and Gaussian Processes to optimally combine and integrate them, based on a set of training examples of alanine mutations. We show that our approach is effective in predicting hot spots and it compares favourably to other available methods. In particular we find the best performances using Transductive Support Vector Machines, a semi-supervised learning scheme. When hot spots are defined as those residues for which ΔΔG ≥ 2 kcal/mol, our method achieves a precision and a recall respectively of 56% and 65%. Conclusion We have developed an hybrid scheme in which energy terms are used as input features of machine learning models. This strategy combines the strengths of machine learning and energy-based methods. Although so far these two types of approaches have mainly been

  15. Aplicação da técnica de fio quente na determinação das propriedades térmicas de polímeros fundidos Hot wire technique in the determination of thermal properties of melt polymers

    Directory of Open Access Journals (Sweden)

    Wilson N. dos Santos

    2005-11-01

    properties of a material that are needed for heat transfer calculations. Reliable thermal properties values are essential for polymers, both in steady and non-steady state situations. Nowadays, several different techniques for the determination of the thermal diffusivity and thermal conductivity may be found in the literature. In this work, the hot wire parallel technique is employed in the experimental determination of the thermal properties of polymers. Three semi-crystalline polymers (HDPE, LDPE and PP, and two amorphous polymers (PS and HIPS were selected for this work. Samples are prepared through the extrusion process starting from the powder or pellets of the solid polymer. A special mould of stainless steel in the shape of a rectangular parallelepiped provided with ceramic insulators between the hot wire, thermocouple and the mould is employed to store the melt extruded polymer whose thermal properties will be measured. Measurements are carried out from room temperature up to approximately 50 ºC above the melting point. Experimental results obtained are checked against data found in literature and those ones furnished by the manufacturers. A critical analysis of this method shows the advantages and disadvantages of this technique when compared with the laser flash technique.

  16. Estudo do Processo TIG Hot-Wire com Material de Adição AISI-316L Analisando o Efeito do Sopro Magnético do Arco sobre a Diluição do Cordão de Solda

    Directory of Open Access Journals (Sweden)

    Erick Alejandro González Olivares

    Full Text Available Resumo: O processo TIG com adição de arame quente (HotWire é considerado um processo altamente produtivo em comparação ao processo TIG convencional com arame frio (ColdWire, sendo possível alcançar grandes taxas de deposição e baixas porcentagens de diluição, características essas que permitem ao processo ser uma ótima alternativa para aplicações de revestimentos. Existem variadas opções em configurações de circuitos elétricos para aquecer o arame de adição no processo TIG Hot-Wire, entre elas podemos destacar a utilização da corrente contínua pulsada e a corrente alternada. No presente trabalho foi utilizada a corrente contínua constante e foram estudadas duas configurações do circuito elétrico para aquecer o material de adição, as quais em teoria provocam diferentes comportamentos no arco voltaico e, portanto, nas propriedades geométricas do cordão de solda. Uma primeira análise realizada sobre o arco voltaico demonstra que se forma um sopro mágnetico constante ao se aquecer o arame com corrente contínua constante. Segundo os ensaios realizados, a direção do sopro magnético depende da polaridade da corrente para aquecer o arame. Uma análise macrográfica dos cordões de solda obtidos demonstraram que os melhores resultados foram para os ensaios feitos com Hot-Wire, conseguindo diluições de até um 2% aproximadamente para uma velocidade de arame de 7,5 m/min, 1 kW de potência de aquecimento do arame e usando uma velocidade de soldagem de 30 cm/min.

  17. Automatic wire twister.

    Science.gov (United States)

    Smith, J F; Rodeheaver, G T; Thacker, J G; Morgan, R F; Chang, D E; Fariss, B L; Edlich, R F

    1988-06-01

    This automatic wire twister used in surgery consists of a 6-inch needle holder attached to a twisting mechanism. The major advantage of this device is that it twists wires significantly more rapidly than the conventional manual techniques. Testing has found that the ultimate force required to disrupt the wires twisted by either the automatic wire twister or manual techniques did not differ significantly and was directly related to the number of twists. The automatic wire twister reduces the time needed for wire twisting without altering the security of the twisted wire.

  18. The heterogeneous electrochemical characteristics of mild steel in the presence of local glucose oxidase-A study by the wire beam electrode method

    Energy Technology Data Exchange (ETDEWEB)

    Wang Wei [Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, College of Chemistry and Chemical Engineering, Qingdao 266100 (China)], E-mail: wwei@ouc.edu.cn; Lu Yonghong; Zou Yan; Zhang Xia [Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, College of Chemistry and Chemical Engineering, Qingdao 266100 (China); Wang Jia [Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, College of Chemistry and Chemical Engineering, Qingdao 266100 (China); State Key Laboratory for Corrosion and Protection, Shenyang 110016 (China)

    2010-03-15

    The influence of glucose oxidase (GOD) activity on the heterogeneous electrochemistry at artificial biofilm/mild steel interface was first characterized by the wire beam electrode (WBE) method. Potential/current distribution maps show that a cathodic zone can be formed at the GOD capsule site. The cathodic zone is gradually weakened due to the gluconic acid production in seawater. When GOD capsule is confined on rusted WBE surfaces, the formerly formed anodic zone is gradually changed into cathodic zone, in the presence of glucose. The novel device developed in our laboratory demonstrates powerful applications in heterogeneous electrochemistry measurements at the biofilm/mild steel interfaces.

  19. The Simulation and Analysis of the Closed Die Hot Forging Process by A Computer Simulation Method

    Directory of Open Access Journals (Sweden)

    Dipakkumar Gohil

    2012-06-01

    Full Text Available The objective of this research work is to study the variation of various parameters such as stress, strain, temperature, force, etc. during the closed die hot forging process. A computer simulation modeling approach has been adopted to transform the theoretical aspects in to a computer algorithm which would be used to simulate and analyze the closed die hot forging process. For the purpose of process study, the entire deformation process has been divided in to finite number of steps appropriately and then the output values have been computed at each deformation step. The results of simulation have been graphically represented and suitable corrective measures are also recommended, if the simulation results do not agree with the theoretical values. This computer simulation approach would significantly improve the productivity and reduce the energy consumption of the overall process for the components which are manufactured by the closed die forging process and contribute towards the efforts in reducing the global warming.

  20. Stretched Wire Mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Bowden, Gordon; /SLAC

    2005-09-06

    Stretched wires are beginning to play an important role in the alignment of accelerators and synchrotron light sources. Stretched wires are proposed for the alignment of the 130 meter long LCLS undulator. Wire position technology has reached sub-micron resolution yet analyses of perturbations to wire straightness are hard to find. This paper considers possible deviations of stretched wire from the simple 2-dimensional catenary form.

  1. Hot Blade Cuttings for the Building Industries

    DEFF Research Database (Denmark)

    Brander, David; Bærentzen, Jakob Andreas; Evgrafov, Anton

    2016-01-01

    . The project aims to reduce the amount of manual labour as well as production time by applying robots to cut expanded polystyrene (EPS) moulds for the concrete to form doubly curved surfaces. The scheme is based upon the so-called Hot Wire or Hot Blade technology where the surfaces are essentially swept out...

  2. Seasonal performance calculation for residential heat pumps with combined space heating and hot water production (FHBB method)

    Energy Technology Data Exchange (ETDEWEB)

    Wemhoener, C.; Afjei, Th

    2003-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) presents the results of work done at the University of Applied Sciences Basel, in Muttenz, Switzerland, on the development of a simple method of calculating the seasonal performance of residential heat pumps that are used to simultaneously provide heat for both space heating and hot water preparation. The report reviews the 'state of the art' concerning calculation methods and existing standards and discusses the shortcomings of some of these methods as a basis for the further development. The principles of the method proposed are explained and the calculation steps involved are described. Sources for base-data for the individual calculation steps are described, such as meteorological data, heat-source temperature, heating and hot water demand and the coefficient of performance of the heat pumps used. Also, heat losses due to cyclic operation, test procedures and factors for simultaneous operation are discussed, whereby both theoretical values and results from simulations are presented. Finally, the method is applied to two sample systems.

  3. Solution of boundary heat transfer coefficients between hot stamping die and cooling water based on FEM and optimization method

    Science.gov (United States)

    Li, Huiping; He, Lianfang; Zhang, Chunzhi; Cui, Hongzhi

    2016-04-01

    The thermal physical parameters have significant effects on the calculation accuracy of physical fields, and the boundary heat transfer coefficient between the die and water is one of the most important thermal physical parameters in the hot stamping. In order to attain the boundary heat transfer coefficient, the testing devices and test procedures are designed according to the characteristic of heat transfer in the hot stamping die. A method of estimating the temperature-dependent boundary heat transfer coefficient is presented, and an inverse heat conduction software is developed based on finite element method, advance-retreat method and golden section method. The software is used to calculate the boundary heat transfer coefficient according to the temperatures measured by NiCr-NiSi thermocouples in the experiment. The research results show that, the convergence of the method given in the paper is well, the surface temperature of sample has a significant effect on the boundary heat transfer coefficient between the die and water. The boundary heat transfer coefficient increases as the surface temperature of sample reduces, and the variation is nonlinear.

  4. Double Fillet Welding of Carbon Steel T-Joint by Double Channel Shielding Gas Metal Arc Welding Method Using Metal Cored Wire

    Directory of Open Access Journals (Sweden)

    Mert T.

    2017-06-01

    Full Text Available Low carbon steel material and T-joints are frequently used in ship building and steel constructions. Advantages such as high deposition rates, high quality and smooth weld metals and easy automation make cored wires preferable in these industries. In this study, low carbon steel materials with web and flange thicknesses of 6 mm, 8 mm and 10 mm were welded with conventional GMAW and double channel shielding gas metal arc welding (DMAG method to form double fillet T-joints using metal cored wire. The difference between these two methods were characterized by measurements of mean welding parameters, Vickers hardness profiles, weld bead and HAZ geometry of the joints and thermal camera temperature measurements. When weld bead and HAZ geometries are focused, it was seen filler metal molten area increased and base metal molten area decreased in DMAG of low carbon steel. When compared with traditional GMAW, finer and acicular structures in weld metal and more homogenous and smaller grains in HAZ are obtained with double channel shielding gas metal arc welding.

  5. Evaluations of different domestic hot water preparing methods with ultra-low-temperature district heating

    DEFF Research Database (Denmark)

    Yang, Xiaochen; Li, Hongwei; Svendsen, Svend

    2016-01-01

    of Legionella in the DHW (domestic hot water) and assure the comfortable temperature, all substations were installed with supplementary heating devices. Detailed measurements were taken in the substations, including the electricity demand of the supplementary heating devices. To compare the energy and economic...... performance of the substations, separate models were built based on standard assumptions. The relative heat and electricity delivered for preparing DHW were calculated. The results showed that substations with storage tanks and heat pumps have high relative electricity demand, which leads to higher integrated...

  6. Method for Hot Real-Time Analysis of Pyrolysis Vapors at Pilot Scale

    Energy Technology Data Exchange (ETDEWEB)

    Pomeroy, Marc D [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-09-29

    Pyrolysis oils contain more than 400 compounds, up to 60% of which do not re-volatilize for subsequent chemical analysis. Vapor chemical composition is also complicated as additional condensation reactions occur during quenching and collection of the product. Due to the complexity of the pyrolysis oil, and a desire to catalytically upgrade the vapor composition before condensation, online real-time analytical techniques such as Molecular Beam Mass Spectrometry (MBMS) are of great use. However, in order to properly sample hot pyrolysis vapors at the pilot scale, many challenges must be overcome.

  7. Controlled rolling process for dual phase steels and application to rod, wire, sheet and other shapes

    Science.gov (United States)

    Thomas, Gareth; Ahn, Jae-Hwan; Kim, Nack-Joon

    1986-01-01

    An improved, energy efficient, hot rolling method for direct production of cold formable dual-phase steel is provided. The steel is heated to completely austenitize it and then continuously hot rolled and cooled down into the ferrite-austenite two phase region to a temperature which is just below the effective Ar.sub.3 temperature. The hot rolled steel is then rapidly quenched to provide an alloy containing strong, tough lath martensite (fibers) in a ductile soft ferrite matrix. The method is particularly useful for providing rods in which form the alloy is capable of being drawn into high strength wire or the like in a cold drawing operation without any intermediate annealing or patenting, and has excellent strength, ductility and fatigue characteristics.

  8. Controlled rolling process for dual phase steels and application to rod, wire, sheet and other shapes

    Science.gov (United States)

    Thomas, G.; Ahn, J.H.; Kim, N.J.

    1986-10-28

    An improved, energy efficient, hot rolling method for direct production of cold formable dual-phase steel is provided. The steel is heated to completely austenitize it and then continuously hot rolled and cooled down into the ferrite-austenite two phase region to a temperature which is just below the effective Ar[sub 3] temperature. The hot rolled steel is then rapidly quenched to provide an alloy containing strong, tough lath martensite (fibers) in a ductile soft ferrite matrix. The method is particularly useful for providing rods in which form the alloy is capable of being drawn into high strength wire or the like in a cold drawing operation without any intermediate annealing or patenting, and has excellent strength, ductility and fatigue characteristics. 3 figs.

  9. Validation of a non-uniform meshing algorithm for the 3D-FDTD method by means of a two-wire crosstalk experimental set-up

    Directory of Open Access Journals (Sweden)

    Raúl Esteban Jiménez-Mejía

    2015-06-01

    Full Text Available This paper presents an algorithm used to automatically mesh a 3D computational domain in order to solve electromagnetic interaction scenarios by means of the Finite-Difference Time-Domain -FDTD-  Method. The proposed algorithm has been formulated in a general mathematical form, where convenient spacing functions can be defined for the problem space discretization, allowing the inclusion of small sized objects in the FDTD method and the calculation of detailed variations of the electromagnetic field at specified regions of the computation domain. The results obtained by using the FDTD method with the proposed algorithm have been contrasted not only with a typical uniform mesh algorithm, but also with experimental measurements for a two-wire crosstalk set-up, leading to excellent agreement between theoretical and experimental waveforms. A discussion about the advantages of the non-uniform mesh over the uniform one is also presented.

  10. Static Hot Air and Infrared Rays Roasting are Efficient Methods for Aflatoxin Decontamination on Hazelnuts

    Directory of Open Access Journals (Sweden)

    Ilenia Siciliano

    2017-02-01

    Full Text Available Aflatoxins are a group of secondary metabolites produced by members of Aspergillus Section Flavi that are dangerous to humans and animals. Nuts can be potentially contaminated with aflatoxins, often over the legal threshold. Food processes, including roasting, may have different effects on mycotoxins, and high temperatures have proven to be very effective in the reduction of mycotoxins. In this work, two different roasting methods—traditional static hot air roasting and infra-red rays roasting—were applied and compared for the detoxification of hazelnuts from Italy and Turkey. At the temperature of 140 °C for 40 min of exposure, detoxification was effective for both roasting techniques. Residual aflatoxins after infra-red rays treatments were lower compared to static hot air roasting. On Italian hazelnuts, residual aflatoxins were lower than 5%, while for Turkish hazelnuts they were lower than 15% after 40 min of exposure to an infra-red rays roaster. After roasting, the perisperm was detached from the nuts and analyzed for aflatoxin contents. Residual aflatoxins in the perisperm ranged from 80% up to 100%. After roasting, the lipid profile and the nutritional quality of hazelnuts were not affected. Fatty acid methyl esters analyses showed a similar composition for Italian and Turkish hazelnuts.

  11. Methods and sorbents for utilizing a hot-side electrostatic precipitator for removal of mercury from combustion gases

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, Sidney [Hudson, OH

    2011-02-15

    Methods are provided for reducing emission of mercury from a gas stream by treating the gas with carbonaceous mercury sorbent particles to reduce the mercury content of the gas; collecting the carbonaceous mercury sorbent particles on collection plates of a hot-side ESP; periodically rapping the collection plates to release a substantial portion of the collected carbonaceous mercury sorbent particles into hoppers; and periodically emptying the hoppers, wherein such rapping and emptying are done at rates such that less than 70% of mercury adsorbed onto the mercury sorbent desorbs from the collected mercury sorbent into the gas stream.

  12. Phosphorus in antique iron music wire.

    Science.gov (United States)

    Goodway, M

    1987-05-22

    Harpsichords and other wire-strung musical instruments were made with longer strings about the beginning of the 17th century. This change required stronger music wire. Although these changes coincided with the introduction of the first mass-produced steel (iron alloyed with carbon), carbon was not found in samples of antique iron harpsichord wire. The wire contained an amount of phosphorus sufficient to have impeded its conversion to steel, and may have been drawn from iron rejected for this purpose. The method used to select pig iron for wire drawing ensured the highest possible phosphorus content at a time when its presence in iron was unsuspected. Phosphorus as an alloying element has had the reputation for making steel brittle when worked cold. Nevertheless, in replicating the antique wire, it was found that lowcarbon iron that contained 0.16 percent phosphorus was easily drawn to appropriate gauges and strengths for restringing antique harpsichords.

  13. Estimation of whole lemon mass transfer parameters during hot air drying using different modelling methods

    Science.gov (United States)

    Torki-Harchegani, Mehdi; Ghanbarian, Davoud; Sadeghi, Morteza

    2015-08-01

    To design new dryers or improve existing drying equipments, accurate values of mass transfer parameters is of great importance. In this study, an experimental and theoretical investigation of drying whole lemons was carried out. The whole lemons were dried in a convective hot air dryer at different air temperatures (50, 60 and 75 °C) and a constant air velocity (1 m s-1). In theoretical consideration, three moisture transfer models including Dincer and Dost model, Bi- G correlation approach and conventional solution of Fick's second law of diffusion were used to determine moisture transfer parameters and predict dimensionless moisture content curves. The predicted results were then compared with the experimental data and the higher degree of prediction accuracy was achieved by the Dincer and Dost model.

  14. New investigation of distribution imaging and content uniformity of very low dose drugs using hot-melt extrusion method.

    Science.gov (United States)

    Park, Jun-Bom; Kang, Chin-Yang; Kang, Wie-Soo; Choi, Han-Gon; Han, Hyo-Kyung; Lee, Beom-Jin

    2013-12-31

    The content uniformity of low dose drugs in dosage forms is very important for quality assurance. The aim of this study was to prepare uniformly and homogeneously distributed dosage forms of very low-dose drugs using twin screw hot-melt extrusion (HME) and to investigate the distribution of drugs using instrumental analyses. For the feasibility of HME method, a very low amount of coumarin-6, a fluorescent dye, was used to visualize distribution images using confocal laser scanning microscope (CLSM). Limaprost, tamsulosin and glimepiride were then used as low-dose model drugs to study the applicability of HME for content uniformity and distribution behaviors. Hydrophilic thermosensitive polymers with low melting point, such as Poloxamer188 and polyethylene glycol (PEG) 6000, were chosen as carriers. The melt extrusion was carried out around 50°C, at which both carriers were easily dissolved but model drugs remained in solid form. The physicochemical properties of the hot-melt extrudates, including differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD) and Fourier transform infrared spectroscopy (FT-IR), were measured. Content uniformity of the drugs was also checked by HPLC. CLSM imaging showed that model drugs were well distributed throughout the hot-melt extrudate, giving better content uniformity with low batch-to-batch variations compared with simple physical mixtures. DSC, PXRD and FT-IR data showed that there was no interaction or interference between model drugs and thermosensitive polymers. The current HME methods could be used to prepare uniformly distributed and reproducible solid dosage forms containing very low dose drugs for further pharmaceutical applications. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Laser Wire Stripper

    Science.gov (United States)

    1983-01-01

    NASA-developed space shuttle technology is used in a laser wire stripper designed by Raytheon Company. Laser beams cut through insulation on a wire without damaging conductive metal, because laser radiation that melts plastic insulation is reflected by the metal. The laser process is fast, clean, precise and repeatable. It eliminates quality control problems and the expense of rejected wiring.

  16. A Vibrating Wire System For Quadrupole Fiducialization

    Energy Technology Data Exchange (ETDEWEB)

    Wolf, Zachary

    2010-12-13

    A vibrating wire system is being developed to fiducialize the quadrupoles between undulator segments in the LCLS. This note provides a detailed analysis of the system. The LCLS will have quadrupoles between the undulator segments to keep the electron beam focused. If the quadrupoles are not centered on the beam axis, the beam will receive transverse kicks, causing it to deviate from the undulator axis. Beam based alignment will be used to move the quadrupoles onto a straight line, but an initial, conventional alignment must place the quadrupole centers on a straight line to 100 {micro}m. In the fiducialization step of the initial alignment, the position of the center of the quadrupole is measured relative to tooling balls on the outside of the quadrupole. The alignment crews then use the tooling balls to place the magnet in the tunnel. The required error on the location of the quadrupole center relative to the tooling balls must be less than 25 {micro}m. In this note, we analyze a system under construction for the quadrupole fiducialization. The system uses the vibrating wire technique to position a wire onto the quadrupole magnetic axis. The wire position is then related to tooling balls using wire position detectors. The tooling balls on the wire position detectors are finally related to tooling balls on the quadrupole to perform the fiducialization. The total 25 {micro}m fiducialization error must be divided between these three steps. The wire must be positioned onto the quadrupole magnetic axis to within 10 {micro}m, the wire position must be measured relative to tooling balls on the wire position detectors to within 15 {micro}m, and tooling balls on the wire position detectors must be related to tooling balls on the quadrupole to within 10 {micro}m. The techniques used in these three steps will be discussed. The note begins by discussing various quadrupole fiducialization techniques used in the past and discusses why the vibrating wire technique is our method

  17. Correlated atomic wires on substrates. II. Application to Hubbard wires

    Science.gov (United States)

    Abdelwahab, Anas; Jeckelmann, Eric; Hohenadler, Martin

    2017-07-01

    In the first part of our theoretical study of correlated atomic wires on substrates, we introduced lattice models for a one-dimensional quantum wire on a three-dimensional substrate and their approximation by quasi-one-dimensional effective ladder models [Abdelwahab et al., preceding paper, Phys. Rev. B 96, 035445 (2017), 10.1103/PhysRevB.96.035445]. In this second part, we apply this approach to the case of a correlated wire with a Hubbard-type electron-electron repulsion deposited on an insulating substrate. The ground-state and spectral properties are investigated numerically using the density-matrix renormalization group method and quantum Monte Carlo simulations. As a function of the model parameters, we observe various phases with quasi-one-dimensional low-energy excitations localized in the wire, namely, paramagnetic Mott insulators, Luttinger liquids, and spin-1 /2 Heisenberg chains. The validity of the effective ladder models is assessed for selected parameters by studying the dependence of results on the number of legs and comparing to the full three-dimensional model. We find that narrow ladder models accurately reproduce the quasi-one-dimensional excitations of the full three-dimensional model but predict only qualitatively whether excitations are localized around the wire or delocalized in the three-dimensional substrate.

  18. Surface hardening of St41 low carbon steel by using the hot-pressing powder-pack boriding method

    Science.gov (United States)

    Sutrisno, Soegijono, Bambang

    2014-03-01

    This research describes a powder-pack boriding process by using hot-pressing technic for St41 low carbon steel which will improve the hardness on the substrate by forming boride layer solid solution. Those method can reduce the operational cost of the research if it is compared by the conventional method with the asmospheric condition both vacuum system and gas inert condition. The concept of boriding by hot-pressing technic was verified in a laboratory scale. Welldefined and reusedable technic was achieved by using the stainless steel 304 as the container and sealed with a 5 ton pressure. This container was filled boronizing powder consisting of 5%B4C, 90%SiC, and 5%KBF4 to close the St41 low carbon steel specimen inside the container. The St41 boriding specimen was treated at the temperature of 900°C for 8 hours. The boride layer on the substrate was found as FeB and Fe2B phase with the hardness about 1800 HV. This value was more than ten times if compared with the untreated specimen that only had the hardness of 123 HV. Depend on heat treatment temperature, heat treatment time, and powder-pack boriding pressure, the depth of boride layer range from 127 to 165 μm, leading to a diffusion controlled process.

  19. Flicking-wire drag tensioner

    Science.gov (United States)

    Dassele, M. A.; Fairall, H.

    1978-01-01

    Wire-drag system improves wire profile and applies consistent drag to wire. Wire drag is continuously adjustable from zero drag to tensile strength of wire. No-sag wire drag is easier to thread than former system and requires minimal downtime for cleaning and maintenance.

  20. Method for the calculation of the annual energy consumption of hot water installations; Methode zur Berechnung des Jahresenergieverbrauchs von Warmwasseranlagen. Entwicklung einer Handrechenmethode mit einfachem EXCEL-Tool

    Energy Technology Data Exchange (ETDEWEB)

    Weber, A.; Poretti, M. [Amstein und Walthert AG, Zuerich (Switzerland); Tschui, A. [Hochschule fuer Technik und Architektur (HTA) Luzern, Horw (Switzerland); Nipkow, J. [Arena, Zuerich (Switzerland)

    2005-12-15

    This comprehensive report for the Swiss Federal Office of Energy (SFOE) presents a simple method for the calculation of the annual energy consumption of installations for the preparation of domestic hot water. A simple EXCEL-based tool is introduced. Three variants are presented for domestic, school and office applications. Various piping configurations and usage types are considered, as are storage and distribution losses. The simulation methods used and various consumption profiles are described and formulas for the calculation of energy supply, storage and consumption are presented.

  1. The 2d-LCA as an alternative to x-wires

    Science.gov (United States)

    Puczylowski, Jaroslaw; Hölling, Michael; Peinke, Joachim

    2015-11-01

    The 2d-Laser Cantilever Anemometer (2d-LCA) is an innovative sensor for two-dimensional velocity measurements in fluids. It uses a micostructured cantilever made of silicon and SU-8 as a sensing element and is capable of performing mesurements with extremly high temporal resolutions up to 150kHz. The size of the cantilever defines its spatial resolution, which is in the order of 150 μm only. Another big feature is a large angular range of 180° in total. The 2d-LCA has been developed as an alternative measurement method to x-wires with the motivation to create a sensor that can operate in areas where the use of hot-wire anemometry is difficult. These areas include measurements in liquids and in near-wall or particle-laden flows. Unlike hot-wires, the resolution power of the 2d-LCA does not decrease with increasing flow velocity, making it particularly suitable for measurements in high speed flows. Comparative measurements with the 2d-LCA and hot-wires have been carried out in order to assess the performance of the new anemometer. The data of both measurement techniques were analyzed using the same stochastic methods including a spectral analysis as well as an inspection of increment statistics and structure functions. Furthermore, key parameters, such as mean values of both velocity components, angles of attack and the characteristic length scales were determined from both data sets. The analysis reveals a great agreement between both anemometers and thus confirms the new approach.

  2. On grouping individual wire segments into equivalent wires or chains, and introduction of multiple domain basis functions

    CSIR Research Space (South Africa)

    Lysko, AA

    2009-06-01

    Full Text Available The paper introduces a method to cover several wire segments with a single basis function, describes related practical algorithms, and gives some results. The process involves three steps: identifying chains of wire segments, splitting the chains...

  3. PS wire chamber

    CERN Multimedia

    1970-01-01

    A wire chamber used at CERN's Proton Synchrotron accelerator in the 1970s. Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

  4. Evaluation of tensile strength and surface topography of orthodontic wires after infection control procedures: An in vitro study

    Directory of Open Access Journals (Sweden)

    M Brindha

    2014-01-01

    Full Text Available Aim: The aim of this study is to evaluate, the influence of four types of sterilization/disinfection procedures (autoclave, hot air oven, glutaraldehyde, and ultraviolet [UV] light on the tensile strength and surface topography of three orthodontic wires (stainless steel (SS, titanium - molybdenum alloy [TMA], and cobalt chromium (CoCr. Materials and Methods: Sample comprised of three types of 8 inches straight length segments of orthodontic wires. They were divided into three groups according to wire composition comprising of 50 samples each. Totally 50 samples of each group were then equally divided into five subgroups according to sterilization method. After sterilization and disinfection of the experimental group, surface topography was examined with scanning electron microscope (SEM and tensile strength was tested using universal testing machine. Result: The results of this study show that the mean ultimate tensile strength (UTS of SS wire after four sterilization procedures were similar to the control group (1845.815 ± 142.29 MPa.The mean UTS of TMA wire increases after four sterilization procedures when compared with the control group (874.107 ± 275.939 MPa. The mean UTS of CoCr wire remains same after UV light disinfection, but increases after other three sterilization procedures when compared with the control group (1449.759 ± 156.586 MPa. SEM photographs of the present study shows gross increase in pitting roughness of the surface topography of all the three types of wires after four types of sterilization. Conclusion: Orthodontists who want to offer maximum safety for their patients can sterilize orthodontic wires before placement, as it does not deteriorate the tensile strength and surface roughness of the alloys.

  5. Injection deep level transient spectroscopy: An improved method for measuring capture rates of hot carriers in semiconductors

    Science.gov (United States)

    Fleming, R. M.; Seager, C. H.; Lang, D. V.; Campbell, J. M.

    2015-07-01

    An improved method for measuring the cross sections for carrier trapping at defects in semiconductors is described. This method, a variation of deep level transient spectroscopy (DLTS) used with bipolar transistors, is applied to hot carrier trapping at vacancy-oxygen, carbon-oxygen, and three charge states of divacancy centers (V2) in n- and p-type silicon. Unlike standard DLTS, we fill traps by injecting carriers into the depletion region of a bipolar transistor diode using a pulse of forward bias current applied to the adjacent diode. We show that this technique is capable of accurately measuring a wide range of capture cross sections at varying electric fields due to the control of the carrier density it provides. Because this technique can be applied to a variety of carrier energy distributions, it should be valuable in modeling the effect of radiation-induced generation-recombination currents in bipolar devices.

  6. An Experimental Study Of Aluminum Alloy Matrix Composite Reinforced SiC Made By Hot Pressing Method

    Directory of Open Access Journals (Sweden)

    Suśniak M.

    2015-06-01

    Full Text Available The present work investigates the possibility of using powder metallurgy processing for producing a metal matrix composite. Materials were prepared from AlSi5Cu2 chips with reinforcement of 10, 15, 20 wt. % silicon carbide. Aluminum alloy chips were milled with SiC powder in a high-energy ball mill by 40 hours. Mechanical alloying process lead to obtain an uniform distribution of hard SiC particles in the metallic matrix and refine the grain size. The consolidation of composite powders was performed by vacuum hot pressing at 450°C, under pressure of 600 MPa by 10 min. The results shows that the addition of SiC particles has a substantial influence on the microstructure and mechanical properties of composite powder as well as consolidated material. Hot pressing is an effective consolidation method which leads to obtain dense AlSi5Cu2/SiC composite with homogeneous structure and advanced mechanical properties.

  7. The effect of self-administered superficial local hot and cold application methods on pain, functional status and quality of life in primary knee osteoarthritis patients.

    Science.gov (United States)

    Aciksoz, Semra; Akyuz, Aygul; Tunay, Servet

    2017-12-01

    To investigate the effect of the self-administered superficial local hot and cold applications on pain, and the functional status and the quality of life in primary knee osteoarthritis patients. Superficial local hot and cold application is used as a nonpharmacological method for the treatment of knee osteoarthritis. However, various guidelines for the management of knee osteoarthritis have conflicting recommendation for hot and cold therapy. A randomised clinical trial design. The sample consisted of patients (n = 96) who were diagnosed with primary knee osteoarthritis. During the application stage, patients were designated to the hot and cold application groups and administered hot and cold application twice a day for 3 weeks together with standard osteoarthritis treatment. The control group only used standard osteoarthritis treatment. The data were collected with a Descriptive Information Form, a Pain Scale, the WOMAC Osteoarthritis Index, the Nottingham Health Profile (NHP) and a Patient Satisfaction Evaluation Form. Outcome measures included pain intensity, functional status and quality of life. We found decreased primary measurement pain scores and improved functional status scores and quality of life scores after the application programme compared to the pre-application stage in both the hot and cold application groups. Once the application was completed, the pain scores, functional status scores and quality-of-life scores on the second measurements were found to be still statistically lower than the pre-application scores but higher than the first measurement ([p  .05). It was found that both hot and cold application resulted in a mild improvement in pain, functional status and quality of life, but this improvement was not sufficient to create a significant difference between the groups. This study contributes to the literature on hot and cold application methods as self-management strategies for patients with knee osteoarthritis. © 2017 John Wiley

  8. A notch-wire composite antenna for polarization diversity reception

    OpenAIRE

    Kuga, Nobuhiro; Arai, H; Goto, N

    1998-01-01

    This paper presents a notch-wire composite antenna for polarization diversity reception in an indoor base-station system, A three-notched disk antenna and a wire antenna are proposed as component antennas for the horizontal and the vertical polarization, respectively. These component antennas are unified as a single composite diversity antenna by mounting the wire antenna on the notched disk. Antenna characteristics are calculated using the method of moments (MoM) with wire grid models and ex...

  9. Mechanochemical Effects on the Synthesis of Copper Orthophosphate and cyclo-Tetraphosphate Bulks by the Hydrothermal Hot Pressing Method

    Directory of Open Access Journals (Sweden)

    Isao Tanaka

    2009-01-01

    Full Text Available Copper orthophosphate, Cu3(PO42, and cyclo-tetraphosphates, Cu2P4O12, were synthesized using phosphoric acid and basic copper carbonate, and then treated with a planetary mill for up to 360 minutes. The un-milled and milled samples were characterized by X-ray diffraction (XRD and Fourier transform infrared (FT-IR spectroscopy. SEM images, particle size distribution, specific surface area, UV-Vis reflectance spectra were also used to evaluate the materials. The un-milled and milled materials were used to fabricate copper phosphate bulks by a hydrothermal hot pressing method. The influence of powder condition on the sintering behavior of the copper phosphates was studied.

  10. The Eulerian buckling test for orthodontic wires.

    Science.gov (United States)

    De Santis, R; Dolci, F; Laino, A; Martina, R; Ambrosio, L; Nicolais, L

    2008-04-01

    Orthodontic treatment is mainly dependent on the loads developed by metal wires. The load developed by a buckled orthodontic wire is of great concern for molar distalization and cannot be simply derived from mechanical properties measured through classical tests (i.e. tensile, torsion, and bending). A novel testing method, based on the Eulerian approach of a simple supported beam, has been developed in order to measure the load due to buckling of orthodontic wires. Elastic titanium molybdenum alloy (TMA; SDS Ormco) and superelastic Nitinol (3M Unitek) and copper nickel-titanium (NiTi; SDS Ormco) wires, each having a rectangular cross section of 0.016 x 0.022 square inches (0.41 x 0.56 mm(2)), were used. The wires were activated and deactivated by loading and unloading. In order to analyse thermo-mechanical properties in buckling, mechanical tests were assisted by calorimetric measurements through differential scanning calorimetry (DSC). Statistical analysis to determine differences between the samples was undertaken using two-way analysis of variance (ANOVA) and Tukey's post hoc test, and one-way ANOVA to assess differences between the tested wires under similar conditions and different materials. The results suggest that the load due to buckling depends on material composition, wire length, the amount of activation, temperature, and deformation rate. The results can be considered as the lower bound for the loads experienced by teeth as far as a buckled wire is concerned. At a temperature higher than the austenite finish transition temperature, superelastic wires were strongly dependent on temperature and deformation rate. The effect due to an increase of deformation rate was similar to that of a decrease of temperature. Load variations due to temperature of a superelastic wire with a length of 20 mm were estimated to be approximately 4 g/degrees C. The high performance of an applied superelastic wire may be related to the high dynamics of the load in relation to

  11. Peripheral nerve repair: a hot spot analysis on treatment methods from 2010 to 2014

    Directory of Open Access Journals (Sweden)

    Guang-yao Liu

    2015-01-01

    Full Text Available Therapeutic strategies for neurological deficits and for promoting nerve regeneration after peripheral nerve injuries have received much focus in clinical research. Advances in basic research in recent years have increased our understanding of the anatomy of peripheral nerves and the importance of the microenvironment. Various new intervention methods have been developed, but with varying effectiveness. In the present study, we selected 911 papers on different repair methods for peripheral nerve injury from the Web of Science and indexed in the Science Citation Index from 2010 to 2014. We quantitatively examine new repair methods and strategies using bibliometrics, and we discuss the present state of knowledge and the problems and prospects of various repair methods, including nerve transfer, neural transplantation, tissue engineering and genetic engineering. Our findings should help in the study and development of repair methods for peripheral nerve injury.

  12. Transport current density at temperatures up to 25 K of Cu/Ag composite sheathed 122-type tapes and wires

    Science.gov (United States)

    Liu, Shifa; Lin, Kaili; Yao, Chao; Zhang, Xianping; Dong, Chiheng; Wang, Dongliang; Awaji, Satoshi; Kumakura, Hiroaki; Ma, Yanwei

    2017-11-01

    The fabrication of iron-based superconductors with high transport critical current density (J c) and low cost is a crucial determinant of whether they can be used for practical applications. In this paper, Cu/Ag composite sheathed Sr0.6K0.4Fe2As2 (Sr122) tapes and Ba0.6K0.4Fe2As2 (Ba122) round wires were fabricated via an ex situ powder-in-tube method and heat-treated by the hot pressing and hot isostatic pressing process respectively. In order to thoroughly reveal the application potential of Cu/Ag composite sheathed ‘122’ iron pnictide superconductors, transport J c of tapes and wires in high fields at temperatures up to 25 K was measured. High transport J c of 4.4 × 104 A cm-2 at 4.2 K and 3.6 × 103 A cm-2 at 20 K in 10 T was achieved in Cu/Ag composite sheathed Sr122 tapes. Transport J c of Ba122 wires is 9.4 × 103 A cm-2 at 4.2 K and 1.9 × 103 A cm-2 at 20 K in 10 T. These results demonstrate the great potential of Cu/Ag composite sheathed ‘122’ iron pnictide superconducting tapes and wires for high-field applications at intermediate temperatures around 20 K, which can be easily obtained by using cryocoolers.

  13. Comparison of brown sugar, hot water, and salt methods for detecting western cherry fruit fly (Diptera: Tephritidae) larvae in sweet cherry

    Science.gov (United States)

    Brown sugar or hot water methods have been developed to detect larvae of tephritid fruit flies in post-harvest fruit in order to maintain quarantine security. It would be useful to determine if variations of these methods can yield better results and if less expensive alternatives exist. This stud...

  14. Transparency in nanophotonic quantum wires

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Mahi R [Department of Physics and Astronomy, University of Western Ontario, London N6A 3K7 (Canada)

    2009-03-28

    We have studied the quantum optics of a photonic quantum nanowire doped with an ensemble of three-level nanoparticles. The wire is made from two photonic crystals A and B. Crystal A is embedded within crystal B and acts as a photonic nanowire. It is considered that the conduction band of crystal A lies below that of crystal B. As a result, photons are confined in crystal A and are reflected from crystal B. The bound states of the confined photons are calculated using the transfer matrix method. It is found that the number of bound states in the wire depends on the size of the wire and the energy difference between the conduction band extrema of crystals A and B. The absorption coefficient of the system has also been calculated using the Schroedinger equation method. It is considered that the nanoparticles interact with the photonic bound states. Numerical simulations show that when one of the resonance energies lies near the bound state, the system becomes transparent. However, when the resonance energy lies away from the bound state the crystal reverts to an absorbing state. Similarly, when the radius of the dielectric spheres is changed the location of the transparency peak is shifted. This means that the present system can be switched between two states by changing the size of the wire and the transition energy. These findings can be used to make new types of optical devices.

  15. Kirschner Wire Breakage during Removal Requiring Retrieval

    Directory of Open Access Journals (Sweden)

    Kai Yuen Wong

    2016-01-01

    Full Text Available Kirschner wires (K-wires are widely used for fixation of fractures and dislocations in the hand as they are readily available, reliable, and cost-effective. Complication rates of up to 18% have been reported. However, K-wire breakage during removal is rare. We present one such case illustrating a simple technique for retrieval. A 35-year-old male presented with a distal phalanx fracture of his right middle finger. This open fracture was treated with K-wire fixation. Postoperatively, he developed a pin site infection with associated finger swelling. The K-wire broke during removal with the proximal piece completely retained in his middle phalanx. To minimise risk of osteomyelitis, the K-wire was removed with a novel surgical technique. He had full return of hand function. Intraoperative K-wire breakage has a reported rate of 0.1%. In our case, there was no obvious cause of breakage and the patient denied postoperative trauma. On the other hand, pin site infections are much more common with reported rates of up to 7% in the hand or wrist. K-wire fixation is a simple method for bony stabilisation but can be a demanding procedure with complications often overlooked. It is important to be aware of the potential sequelae.

  16. Charpak hemispherical wire chamber

    CERN Multimedia

    1970-01-01

    pieces. Mesures are of the largest one. Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

  17. Photovoltaic Wire Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This Small Business Innovation Research Phase I project will investigate a new architecture for photovoltaic devices based on nanotechnology: photovoltaic wire. The...

  18. Development of a method for determination of metallic iron content within hot briquette iron (HBI for steelmaking

    Directory of Open Access Journals (Sweden)

    Morcali M.H.

    2016-01-01

    Full Text Available The growing use of metallic iron in metallurgy and industrial chemical applications requires a fast, easy and cheap method for the determination of metallic iron, not merely in recyclable materials, such as iron pellets, reduced iron mill scale dust, electric arc furnace dust and pig iron, but from hot briquette iron (HBI as well. This study investigates a new method for determination of metallic iron within HBI used for steel-making materials. The effects of reaction time, temperature, and stirring rate were studied. The concentration of iron was determined via Atomic Absorption Spectroscopy (AAS. After the optimization study, high-purity metallic iron powder (Sigma-Aldrich, PubChem Substance ID 24855469 was used to compare efficiencies and identify the optimum conditions; The present study was matched with international standard methods (BS ISO 5416:2006, IS 15774:2007. Results were consistent with certified values and metallic iron content could be determined within the 95% confidence level. The purposed method is easy, straightforward, and cheap.

  19. A suggestion of a new method for the calculation of the coating thickness in continuous hot-dip galvanizing

    Energy Technology Data Exchange (ETDEWEB)

    Jo, C. M.; Kwon, Y. D.; Kwon, S. B. [Kyungpook National University, Daegu (Korea, Republic of); Kim, G. Y. [POSCO Technical Research laboratories, Gumgo-dong (Korea, Republic of)

    2011-11-15

    It is known that the distributions of the impinging pressure gradient and the shear stress at the strip surface play a decisive key role in the decision of the coating thickness in hot-dip galvanizing. So, to predict the exact coating thickness, it is essential that the distributions of the impinging wall jet pressure and the shear stress acting between the liquid film and jet stream are measured (or calculated) exactly for each specific coating condition. So far, to obtain the impinging wall jet pressure, it was assumed that the jet issuing from an air-knife is similar to the Hiemenz plane stagnation flow, and the wall shear stress could be predicted by an equation using the assumption of a non-negative Gaussian profile in impinging wall jet pressure in general, so that it cannot be reliable for some impinging wall jet regions and nozzle systems intrinsically. Nevertheless, one cannot find a suitable method to cope with the difficulties in measuring/calculating of the shear stress and the impinging wall jet pressure. Such a difficulty which will cause an inaccuracy in the coating thickness prediction. With these connections, in the present study, we suggest a new method named as a two-step calculation method to calculate the final coating thickness, which consists of the air jet analysis and coating thickness calculation. And, from the comparison of the results one may confirm the validation of the new suggested method.

  20. New technique of skin embedded wire double-sided laser beam welding

    Science.gov (United States)

    Han, Bing; Tao, Wang; Chen, Yanbin

    2017-06-01

    In the aircraft industry, double-sided laser beam welding is an approved method for producing skin-stringer T-joints on aircraft fuselage panels. As for the welding of new generation aluminum-lithium alloys, however, this technique is limited because of high hot cracking susceptibility and strengthening elements' uneven distributions within weld. In the present study, a new technique of skin embedded wire double-sided laser beam welding (LBW) has been developed to fabricate T-joints consisting of 2.0 mm thick 2060-T8/2099-T83 aluminum-lithium alloys using eutectic alloy AA4047 filler wire. Necessary dimension parameters of the novel groove were reasonably designed for achieving crack-free welds. Comparisons were made between the new technique welded T-joint and conventional T-joint mainly on microstructure, hot crack, elements distribution features and mechanical properties within weld. Excellent crack-free microstructure, uniform distribution of silicon and superior tensile properties within weld were found in the new skin embedded wire double-sided LBW T-joints.

  1. A new method for designing floor slabs on grade due to the difficulty of applying simplified design methods, amongst them being the Portland Cement Association (PCA and Wire Reinforcement Institute (WRI methods

    Directory of Open Access Journals (Sweden)

    Hugo Ernesto Camero Sanabrial

    2007-01-01

    Full Text Available This article presents a methodology for designing slabs on grade for industrial floors where there is an eccentricity between the slab centroid and the gravity centre loads of the loaded axle of forklift trucks travelling over the floor. An example was used for analysing how Portland Cement Association (PCA and the Wire Reinforcement Institute (WRI methods are inadequate for designing floors sublected to this condition. The new proposal for designing slabs on grade for industrial floors has been called the Camero method. An example of an industrial floor designed to be capable of sustaining an infinite number of load applications (or 50-year life was compared to the results of the Camero method and PCA and WRI’s simplified methods. Industrial floors should be capable of sustaining an infinite number of load applications (50-year life if designed with the Camero method; on the other hand, if designed using PCA and WRI methods they will only last one year (in this example the number of axle load applications in a 1-year period was equal to the number of allowable repetitions because they will not be able to sustain an infinite number of load applications. It was concluded that designing plain concrete slabs (without reinforcement on grade according to PCA and the WRI methods leads to slab fatigue, even though extreme fibre stress should not exceed 50 percent (50% of static modulus of concrete rupture and slabs should sustain an infinite number of load repetitions (infinite amount of forklift truck traffic were considered parameters in their design.

  2. 1998 wire development workshop proceedings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-04-01

    This report consists of vugraphs of the presentations at the conference. The conference was divided into the following sessions: (1) First Generation Wire Development: Status and Issues; (2) First Generation Wire in Pre-Commercial Prototypes; (3) Second Generation Wire Development: Private Sector Progress and Issues; (4) Second Generation Wire Development: Federal Laboratories; and (5) Fundamental Research Issues for HTS Wire Development.

  3. TECHNOLOGY FOR OBTAINING BIMETALLIC SHAPING PARTS OF DIE TOOLING USING METHOD OF HIGH-SPEED HOT EXTRUSION

    Directory of Open Access Journals (Sweden)

    I. V. Kachanov

    2014-01-01

    Full Text Available Processes of high-speed shaping changes and especially high-speed hot extrusion create efficient conditions for treatment of weakly plastic and poorly deformable materials which are widely used in tool making facilities. Due to the fact that high-speed stamping provides accurate billets with increased mechanical properties, it can be used as a technological process for manufacturing shaping parts of die tooling parts operating which are subjected to increased loads and wear.The purpose of the paper is to carry out experimental investigations on the possibility to obtain a bimetallic tool where structural steel is considered as a basis of the tool and a working cavity is made of high-alloyed tool steel with its saving up to 90 %. A scheme of loading and geometry of conjugated surfaces of the composite billet have been developed in the paper. Technology for obtaining bimetallic shaping parts of die tooling with deformation at speed of vR = 40-50 m/s and composite billet temperature of T = 1150 °C has been experimentally tested with formation of a compound due to plastic flow of two billet parts on contact surface with removal of surface oxide films.Microstructures of the bimetallic compounds obtained with the help of high-speed hot extrusion method for compositions of structural and high-alloy steels have been investigated and their high quality has been proved during the investigations. Dependences of micro-hardness distribution have been established outbound two- steel contact plane in the zone of connection that are characterized by a minimum micro-hardness value in the connection joint. Availability of more plastic zone in the contact plane contributes to reduction of residual stresses due to their relaxation in this zone and higher joint strength.

  4. Synthesis of large CZTSe nanoparticles through a two-step hot-injection method

    DEFF Research Database (Denmark)

    Engberg, Sara Lena Josefin; Li, Zhenggang; Lek, Jun Yan

    2015-01-01

    Grain boundaries in Cu2ZnSn(SxSe1x)4 (CZTSSe) thin films act as a defect that reduces the mobility of the charges. Hence one way to improve the performance of these thin film solar cells is to increase the grain size in the films. Most of the synthesis methods published so far for CZTSSe colloida...

  5. A mini-scale hot borate method for the isolation of total RNA from a ...

    African Journals Online (AJOL)

    Genetic genomics in cotton requires isolating RNA from a large number of plant tissue samples, in a mapping population. However, traditional methods for the extraction of RNA from cotton tissues is time consuming and not suitable for processing many samples at the same time. Here, we present a miniscale protocol for ...

  6. Infared beak treatment method compared with conventional hot blade amputation in laying hens

    Science.gov (United States)

    Infrared lasers have been widely used for noninvasive surgical applications in human medicine and their results are reliable, predictable and reproducible. Infrared lasers have recently been designed with the expressed purpose of providing a less painful, more precise beak trimming method compared w...

  7. Genetic Optimization of Wire Antennas

    Directory of Open Access Journals (Sweden)

    Z. Raida

    1998-09-01

    Full Text Available The presented submission describes how genetic algorithms can be applied to the optimization and design of wire antennas. The proposed optimization method is easily programmable and well understandable on one hand, but relatively slowly converging and depending on the parameters of the genetic algorithms on the other hand. The disadvantages of the method are deeply discussed and their elimination is discussed in the paper.

  8. Hot-alkaline DNA extraction method for deep-subseafloor archaeal communities.

    Science.gov (United States)

    Morono, Yuki; Terada, Takeshi; Hoshino, Tatsuhiko; Inagaki, Fumio

    2014-03-01

    A prerequisite for DNA-based microbial community analysis is even and effective cell disruption for DNA extraction. With a commonly used DNA extraction kit, roughly two-thirds of subseafloor sediment microbial cells remain intact on average (i.e., the cells are not disrupted), indicating that microbial community analyses may be biased at the DNA extraction step, prior to subsequent molecular analyses. To address this issue, we standardized a new DNA extraction method using alkaline treatment and heating. Upon treatment with 1 M NaOH at 98°C for 20 min, over 98% of microbial cells in subseafloor sediment samples collected at different depths were disrupted. However, DNA integrity tests showed that such strong alkaline and heat treatment also cleaved DNA molecules into short fragments that could not be amplified by PCR. Subsequently, we optimized the alkaline and temperature conditions to minimize DNA fragmentation and retain high cell disruption efficiency. The best conditions produced a cell disruption rate of 50 to 80% in subseafloor sediment samples from various depths and retained sufficient DNA integrity for amplification of the complete 16S rRNA gene (i.e., ∼1,500 bp). The optimized method also yielded higher DNA concentrations in all samples tested compared with extractions using a conventional kit-based approach. Comparative molecular analysis using real-time PCR and pyrosequencing of bacterial and archaeal 16S rRNA genes showed that the new method produced an increase in archaeal DNA and its diversity, suggesting that it provides better analytical coverage of subseafloor microbial communities than conventional methods.

  9. Evaluation of the interfacial shear strength between pseudoplastic NiTi shape memory alloy wires and epoxy by the pull-out method

    Science.gov (United States)

    Spārniņš, E.; Andersons, J.; Michaud, V.; Leterrier, Y.

    2015-12-01

    The interfacial shear strength (IFSS) between nickel-titanium (NiTi) shape memory alloy wires, characterized by a nonlinear stress-strain behavior, and epoxy matrix was determined by pull-out tests. Tests were carried out at several temperatures and levels of pre-strain in the wires, to evaluate the effects of embedded wire length and of crystalline state of the alloy. The IFSS between the twinned NiTi and epoxy was estimated at 24 MPa, and found to increase to 47 MPa for completely detwinned and preloaded martensitic NiTi. This increase in IFSS values was attributed to microcracking of the superficial TiO2 layer and the resulting roughening of the NiTi wire surface.

  10. Separation Test Method for Investigation of Current Density Effects on Bond Wires of SiC Power MOSFET Modules

    DEFF Research Database (Denmark)

    Luo, Haoze; Iannuzzo, Francesco; Blaabjerg, Frede

    2017-01-01

    and average temperature during the test. By analyzing the output characteristics of the linear region of MOSFET, the constraint relations among the gate voltage, on-state voltage drop and junction temperature are revealed in this paper. The one-to-one correspondence between gate voltage and conduction power...... loss can be used to adjust the current density under fixed temperature swing and average temperature. The commercial Silicon Carbide (SiC) MOSFET modules are tested to experimentally verify the proposed method. Finally, the effectiveness of proposed test method is validated by the experimental results....

  11. An on-line method for pressurized hot water extraction and enzymatic hydrolysis of quercetin glucosides from onions.

    Science.gov (United States)

    Lindahl, Sofia; Liu, Jiayin; Khan, Samiullah; Karlsson, Eva Nordberg; Turner, Charlotta

    2013-06-27

    A novel environmentally sound continuous-flow hot water extraction and enzymatic hydrolysis method for determination of quercetin in onion raw materials was successfully constructed using a stepwise optimization approach. In the first step, enzymatic hydrolysis of quercetin-3,4'-diglucoside to quercetin was optimized using a three level central composite design considering temperature (75-95°C), pH (3-6) and volume concentration of ethanol (5-15%). The enzyme used was a thermostable β-glucosidase variant (termed TnBgl1A_N221S/P342L) covalently immobilized on either of two acrylic support-materials (Eupergit(®) C 250L or monolithic cryogel). Optimal reaction conditions were irrespective of support 84°C, 5% ethanol and pH 5.5, and at these conditions, no significant loss of enzyme activity was observed during 72 h of use. In a second step, hot water extractions from chopped yellow onions, run at the optimal temperature for hydrolysis, were optimized in a two level design with respect to pH (2.6 and 5.5), ethanol concentration (0 and 5%) and flow rate (1 and 3 mL min(-1)) Obtained results showed that the total quercetin extraction yield was 1.7 times higher using a flow rate of 3 mL min(-1) (extraction time 90 min), compared to a flow rate of 1 mL min(-1) (extraction time 240 min). Presence of 5% ethanol was favorable for the extraction yield, while a further decrease in pH was not, not even for the extraction step alone. Finally, the complete continuous flow method (84°C, 5% ethanol, pH 5.5, 3 mL min(-1)) was used to extract quercetin from yellow, red and shallot onions and resulted in higher or similar yield (e.g. 8.4±0.7 μmol g(-1) fresh weight yellow onion) compared to a conventional batch extraction method using methanol as extraction solvent. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Transport in quantum wires

    Indian Academy of Sciences (India)

    This motivated us to study the LL model of a quantum wire, with Fermi liquid leads and the unusual feature of ... of quantized conductance even in clean quantum wires and a novel odd–even effect in the presence of a .... But in one dimension, it is well-known that the FL theory breaks down, and the ground state is a ...

  13. Commercial and Industrial Wiring.

    Science.gov (United States)

    Kaltwasser, Stan; Flowers, Gary

    This module is the third in a series of three wiring publications, includes additional technical knowledge and applications required for job entry in the commercial and industrial wiring trade. The module contains 15 instructional units that cover the following topics: blueprint reading and load calculations; tools and equipment; service;…

  14. Traveling Wire Electrical Discharge Machining as an Alternative Method of Manufacturing M1 Main Battle Tank Rotary Shock Absorber Components

    Science.gov (United States)

    1986-09-01

    stamp/ diecast other materials. When tool and die shops use EDM or WEDM to shape tool materials, the slow cutting rate is not a disadvantage because these...materials would take even longer to process by any other method. Furthermore, a die, for example, once processed, can forge/stamp/ diecast a number of

  15. Conjugation of Hot-Melt Extrusion with High-Pressure Homogenization: a Novel Method of Continuously Preparing Nanocrystal Solid Dispersions.

    Science.gov (United States)

    Ye, Xingyou; Patil, Hemlata; Feng, Xin; Tiwari, Roshan V; Lu, Jiannan; Gryczke, Andreas; Kolter, Karl; Langley, Nigel; Majumdar, Soumyajit; Neupane, Dipesh; Mishra, Sanjay R; Repka, Michael A

    2016-02-01

    Over the past few decades, nanocrystal formulations have evolved as promising drug delivery systems owing to their ability to enhance the bioavailability and maintain the stability of poorly water-soluble drugs. However, conventional methods of preparing nanocrystal formulations, such as spray drying and freeze drying, have some drawbacks including high cost, time and energy inefficiency, traces of residual solvent, and difficulties in continuous operation. Therefore, new techniques for the production of nanocrystal formulations are necessary. The main objective of this study was to introduce a new technique for the production of nanocrystal solid dispersions (NCSDs) by combining high-pressure homogenization (HPH) and hot-melt extrusion (HME). Efavirenz (EFZ), a Biopharmaceutics Classification System class II drug, which is used for the treatment of human immunodeficiency virus (HIV) type I, was selected as the model drug for this study. A nanosuspension (NS) was first prepared by HPH using sodium lauryl sulfate (SLS) and Kollidon® 30 as a stabilizer system. The NS was then mixed with Soluplus® in the extruder barrel, and the water was removed by evaporation. The decreased particle size and crystalline state of EFZ were confirmed by scanning electron microscopy, zeta particle size analysis, and differential scanning calorimetry. The increased dissolution rate was also determined. EFZ NCSD was found to be highly stable after storage for 6 months. In summary, the conjugation of HPH with HME technology was demonstrated to be a promising novel method for the production of NCSDs.

  16. Assessment of the hardness of different orthodontic wires and brackets produced by metal injection molding and conventional methods

    Directory of Open Access Journals (Sweden)

    Shiva Alavi

    2017-01-01

    Conclusion: MIM orthodontic brackets exhibited hardness values much lower than those of SS orthodontic archwires and were more compatible with NiTi and beta-titanium archwires. A wide range of microhardness values has been reported for conventional orthodontic brackets and it should be considered that the manufacturing method might be only one of the factors affecting the mechanical properties of orthodontic brackets including hardness.

  17. Impact behaviors of poly-lactic acid based biocomposite reinforced with unidirectional high-strength magnesium alloy wires

    Directory of Open Access Journals (Sweden)

    Xuan Li

    2014-10-01

    Full Text Available A novel poly-lactic acid (PLA based biocomposite reinforced with unidirectional high-strength magnesium alloy (Mg-alloy wires for bone fracture fixation was fabricated by hot-compressing process. The macroscopical and microscopical impact behaviors of the biocomposite were investigated using impact experiments and finite element method (FEM, respectively. The results indicated that the biocomposite had favorable impact properties due to the plastic deformation behavior of Mg-alloy wires during impact process. While the content of Mg-alloy wires reached 20 vol%, the impact strength of the composite could achieve 93.4 kJ/m2, which is approximate 16 times larger than that of pure PLA fabricated by the same process. According to FEM simulation results, the complete destruction life of the composites during impact process increased with increasing volume fraction of Mg-alloy wires, indicating a high impact-bearing ability of the composite for bone fracture fixation. Simultaneously, the energy absorbed by Mg-alloy wires in the composites had a corresponding increase. In addition, it denoted that the impact properties of the composites are sensitive to the initial properties of the matrix material.

  18. Hot Flashes

    Science.gov (United States)

    ... Risk factors Not all women who go through menopause have hot flashes, and it's not clear why some women do have them. Factors that may increase your risk include: Smoking. Women who smoke are more likely to get hot flashes. Obesity. A high body mass index (BMI) is associated ...

  19. Hot flushes

    African Journals Online (AJOL)

    without thermoregulatory homeostatic mechanisms, such as sweating, being triggered. Small fluctuations in core body. Abstract. Vasomotor symptoms, such as hot flushes and night sweats, are considered to be the cardinal symptoms of menopause, and are experienced by most women. The physiology of hot flushes is not ...

  20. Synthesis and characterization of magnetic of Ni/ABS nanocomposites by electrical explosion of wire in liquid and solution blending methods

    Science.gov (United States)

    Thuyet-Nguyen, Minh; Hai-Nguyen, Hong; Kim, Won Joo; Kim, Ho Yoon; Kim, Jin-Chun

    2017-03-01

    Nanomaterials have attracted great attention from chemists, physicists and materials scientists because of their application benefits and special properties. Thermoplastics have been used in many applications such as molding of non-electrical components, conducting, magnetic field and 3D printing. Nanocomposites are known as a material which blends the best properties of components, a high performance material exhibits unusual property combinations and unique design possibilities. In this research, we focused to investigate and report primary results in the synthesis of magnetic nanocomposites based on acrylonitrile butadiene styrene (ABS), which are useful and important thermoplastics. Nickel nanopowder was prepared by electrical explosion of wire in a liquid were used as magnetic component. The composites were prepared by following steps, first the obtained Ni nanopowders were incorporated into the ABS matrix via a solution blending method (drop-casting), and then the solvent was evaporated. The characterizations of obtaining composites were analyzed by field emission scanning electron microscopy, X-Ray Diffraction analysis and vibrating sample magnetometer.

  1. A Laser Based Instrument for MWPC Wire Tension Measurement

    CERN Document Server

    Baldini, W; Evangelisti, F; Germani, S; Landi, L; Savrié, M; Graziani, G; Lenti, M; Lenzi, M; Passaleva, G; Carboni, G; De Capua, S; Kachtchouk, A

    2007-01-01

    A fast and simple method for the measurement of the mechanical tension of wires of Multi Wires Proportional Chambers (MWPCs) is described. The system is based on commercial components and does not require any electrical connection to the wires or electric or magnetic field. It has been developed for the quality control of MWPCs of the Muon Detector of the LHCb experiment in construction at CERN. The system allows a measurement of the wire tension with a precision better than 0.5% within 3-4 seconds per wire

  2. Highly enhanced photoluminescence of AgInS2/ZnS quantum dots by hot-injection method

    Science.gov (United States)

    Liao, Shenghua; Huang, Yu; Zhang, Ying; Shan, Xiaohui; Yan, Zhengyu; Shen, Weiyang

    2015-01-01

    Highly photoluminescent and air-stable AgInS2 quantum dots (AIS QDs) were synthesized by a hot-injection route in N2 atmosphere and dark environment. The as-synthesized AIS QDs were further capped with ZnS shell by one-pot method in order to enhance the photoluminescence (PL) intensity. The photo-electronic property and the morphology of AIS QDs and AIS/ZnS QDs were characterized by ultraviolet-visible spectroscopy (UV), PL spectroscopy and transmission electronic microscopy (TEM). The results indicated that the narrow and symmetrical PL spectra of AIS QDs was time-dependent, and the emission wavelength of AIS QDs could be tunable within 436-610 nm by altering the initial Ag/In ratios. After being capped with ZnS shell, the AIS QDs showed excellent optical characteristics, including PL QYs up to 15%. The TEM results indicated that the spherical AIS/ZnS QDs were nearly monodispersed and homogeneous with an average particle size of 8 nm. The heavy metal free and high luminous AIS/ZnS QDs have great potential in biological application.

  3. Growth and characterization of Mn-doped AgInS{sub 2} grown by a hot-press method

    Energy Technology Data Exchange (ETDEWEB)

    Akaki, Yoji [Department of Electrical and Computer Engineering, Miyakonojo National College of Technology, 473-1 Yoshio, Miyakonojo, Miyazaki (Japan); Shirahata, Yasuhiro; Yoshino, Kenji [Department of Electrical and Electronics Engineering, Miyazaki University, 1-1 Gakuen Kibanadai-nishi, Miyazaki (Japan); Ohno, Yutaka; Yonenaga, Ichiro [Institute for Materials Research, Tohoku University, Aoba-ku, Sendai (Japan)

    2009-05-15

    Mn-doped AgInS{sub 2} crystals are grown by a hot-press method at 700 C for 1 hour under high pressure of 25 MPa from stoichiometric Ag{sub 2}S and In{sub 2}S{sub 3} powders with the Mn atoms with a concentration between 5 and 20 mol.%. Mn-doped crystals showed diffraction lines of orthorhombic AgInS{sub 2} and AgIn{sub 5}S{sub 8} in addition to the dominant lines of chalcopyrite AgInS{sub 2}. The S composition in the crystals is slightly deficient independent of the Mn concentration. Electron states of Mn are studied by an electron spin resonance (ESR) at room temperature. The ESR intensity of the Mn-doped crystals increases with an increase in the Mn concentration. The g-factors at room temperature of the Mn-doped crystals are in the range 1.980-1.982 with the peak-to-peak linewidth in the range 4.5-8.9 mT. (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  4. Multi-Scale Multi-physics Methods Development for the Calculation of Hot-Spots in the NGNP

    Energy Technology Data Exchange (ETDEWEB)

    Downar, Thomas [Univ. of Michigan, Ann Arbor, MI (United States); Seker, Volkan [Univ. of Michigan, Ann Arbor, MI (United States)

    2013-04-30

    Radioactive gaseous fission products are released out of the fuel element at a significantly higher rate when the fuel temperature exceeds 1600°C in high-temperature gas-cooled reactors (HTGRs). Therefore, it is of paramount importance to accurately predict the peak fuel temperature during all operational and design-basis accident conditions. The current methods used to predict the peak fuel temperature in HTGRs, such as the Next-Generation Nuclear Plant (NGNP), estimate the average fuel temperature in a computational mesh modeling hundreds of fuel pebbles or a fuel assembly in a pebble-bed reactor (PBR) or prismatic block type reactor (PMR), respectively. Experiments conducted in operating HTGRs indicate considerable uncertainty in the current methods and correlations used to predict actual temperatures. The objective of this project is to improve the accuracy in the prediction of local "hot" spots by developing multi-scale, multi-physics methods and implementing them within the framework of established codes used for NGNP analysis.The multi-scale approach which this project will implement begins with defining suitable scales for a physical and mathematical model and then deriving and applying the appropriate boundary conditions between scales. The macro scale is the greatest length that describes the entire reactor, whereas the meso scale models only a fuel block in a prismatic reactor and ten to hundreds of pebbles in a pebble bed reactor. The smallest scale is the micro scale--the level of a fuel kernel of the pebble in a PBR and fuel compact in a PMR--which needs to be resolved in order to calculate the peak temperature in a fuel kernel.

  5. Optoelectrical properties for CuAlSe{sub 2} epilayers grown by using a hot wall epitaxy method

    Energy Technology Data Exchange (ETDEWEB)

    Baek, Seoungnam; Hong, Kwangjoon [Chosun University, Kwangju (Korea, Republic of)

    2006-06-15

    CuAlSe{sub 2}(112)/GaAs(100) heteroepitaxial layers were grown by using a hot wall epitaxy (HWE) method. From the measurements of the Laue patterns and the double crystal X-ray diffraction, the CuAlSe{sub 2} epilayer was confirmed to have been epitaxially grown along the <112> direction on the GaAs (100) substrate. The Hall mobility and the carrier density of the CuAlSe{sub 2} epilayer at 293 K were estimated to be 295 cm{sup 2}/V{center_dot}sec and 9.24 x 10{sup 16} cm{sup -3}, respectively. This mobility is about one order higher than the reported value. From the temperature dependence of the Hall mobility, the scattering at high temperatures was mainly due to the acoustic mode of the lattice vibration, and the scattering at low temperatures was predominantly due to the impurity effect. From the low-temperature PL experiment, we observed a sharp and intensive free-exciton peak at 2.7918 eV. That peak is usually not detected because of the difficulty in growing single crystals of high quality. Also, this peak existed at a much shorter wavelength than the 2.739 eV of the free exciton measured from an epilayer grown by using the metalorganic chemical-vapor deposition (MOCVD). These facts indicate that the CuAlSe{sub 2} epilayers grown by using the HWE method are higher quality crystals than those grown by using MOCVD or other methods.

  6. A NOVEL METHOD FOR ANALYZING ELECTRIC FIELD DISTRIBUTION OF ELECTRO CAPACITIVE CANCER TREATMENT (ECCT USING WIRE MESH ELECTRODES: A CASE STUDY OF BRAIN CANCER THERAPY.

    Directory of Open Access Journals (Sweden)

    Linahtadiya Andiani

    2017-12-01

    Full Text Available Electric field distribution analysis generated by ECCT in a human head model with or without brain cancer using wire mesh electrode has been conductedsuccessfully. The analysis of electric field distribution was done using simulation in a human head model with ECCT Apparel Helmet system type A which is three dimensional model. The electric field distribution was measured with and without a wire mesh electrode which was either passive or active using COMSOL Multiphysics 5.2 software and was then processed using MATLAB R2010a. The aim of the research was to assess the performance of wire mesh electrode in detecting electric field distribution. ECCT which is utilized in brain cancer therapy with input 10 V is able to produce an electric field with an average of 178.8 V/m. The input voltage influences electric field distribution whereas the signal frequency does not affect the electric field distribution. Wire mesh electrode which is either active or passive can measure the electric field distribution generated by ECCT that neither the active nor the passive wire mesh electrode changed the pattern of the electric field distribution and the change in the measured electric field value is not significant.

  7. Graphene wire medium: Homogenization and application

    DEFF Research Database (Denmark)

    Andryieuski, Andrei; Chigrin, Dmitry N.; Lavrinenko, Andrei

    2012-01-01

    In this contribution we analyze numerically the optical properties of the graphene wire medium, which unit cell consists of a stripe of graphene embedded into dielectric. We propose a simple method for retrieval of the isofrequency contour and effective permittivity tensor. As an example...... of the graphene wire medium application we demonstrate a reconfigurable hyperlens for the terahertz subwavelength imaging capable of resolving two sources with separation λ0/5 in the far-field....

  8. Ultrathin Nanocrystalline Magnetic Wires

    Directory of Open Access Journals (Sweden)

    Horia Chiriac

    2017-02-01

    Full Text Available The magnetic characteristics of FINEMET type glass-coated nanowires and submicron wires are investigated by taking into account the structural evolution induced by specific annealing all the way from a fully amorphous state to a nanocrystalline structure. The differences between the magnetic properties of these ultrathin wires and those of the thicker glass-coated microwires and “conventional” wires with similar structures have been emphasized and explained phenomenologically. The domain wall propagation in these novel nanowires and submicron wires, featuring a combination between an amorphous and a crystalline structure, has also been studied, given the recent interest in the preparation and investigation of new materials suitable for the development of domain wall logic applications.

  9. Progress in American Superconductor’s HTS wire and optimization for fault current limiting systems

    Energy Technology Data Exchange (ETDEWEB)

    Malozemoff, Alexis P., E-mail: amalozemoff@amsc.com

    2016-11-15

    Highlights: • AMSC HTS wire critical current needed for rotating machinery is doubled by 16 MeV Au irradiation. • Nonuniformity of HTS wires in power devices causes hot spot formation during power system faults. • Lower normal-state resistivity and critical current lower HTS wire hot spot heating during faults. • HTS wire hot spot heating in HTS cables during faults must stay below lN{sub 2} bubble nucleation point. • HTS wire can be designed to meet hot spot heating limits in fault current limiting cables. - Abstract: American Superconductor has developed composite coated conductor tape-shaped wires using high temperature superconductor (HTS) on a flexible substrate with laminated metal stabilizer. Such wires enable many applications, each requiring specific optimization. For example, coils for HTS rotating machinery require increased current density J at 25–50 K. A collaboration with Argonne, Brookhaven and Los Alamos National Laboratories and several universities has increased J using an optimized combination of precipitates and ion irradiation defects in the HTS. Major commercial opportunities also exist to enhance electric power grid resiliency by linking substations with distribution-voltage HTS power cables [10]. Such links provide alternative power sources if one substation's transmission-voltage power is compromised. But they must also limit fault currents which would otherwise be increased by such distribution-level links. This can be done in an HTS cable, exploiting the superconductor-to-resistive transition when current exceeds the wires’ critical J. A key insight is that such transitions are usually nonuniform; so the wire must be designed to prevent localized hot spots from damaging the wire or even generating gas bubbles in the cable causing dielectric breakdown. Analysis shows that local heating can be minimized by increasing the composite tape's total thickness, decreasing its total resistance in the normal state and

  10. Dual wire weld feed proportioner

    Science.gov (United States)

    Nugent, R. E.

    1968-01-01

    Dual feed mechanism enables proportioning of two different weld feed wires during automated TIG welding to produce a weld alloy deposit of the desired composition. The wires are fed into the weld simultaneously. The relative feed rates of the wires and the wire diameters determine the weld deposit composition.

  11. Hot Soak

    OpenAIRE

    Goldwater, H.

    2005-01-01

    The DVD is documentation of Hot Soak, as performed at the Queen’s Hotel, Penzance, Cornwall in an en suite bathroom, for Tract: Live Art Festival, 2006, curated by Art Surgery/ Newlyn Art Gallery. Hot Soak was originally made for home, London, 2005. This piece marries an everyday environment (bathroom) with extraordinary materials (ice cubes/ dress bleeding red into water) creating the surreal. Sontag’s understanding of camp as a love of the unnatural, artifice and exaggeration, can be ci...

  12. Measurement of heat transfer coefficient using termoanemometry methods

    Directory of Open Access Journals (Sweden)

    Dančová P.

    2014-03-01

    Full Text Available This work deals with a measurement of heat transfer from a heated flat plate on which a synthetic jet impacts perpendicularly. Measurement of a heat transfer coefficient (HTC is carried out using the hot wire anemometry method with glue film probe Dantec 55M47. The paper brings also results of velocity profiles measurements and turbulence intensity calculations.

  13. Copper wire bonding

    CERN Document Server

    Chauhan, Preeti S; Zhong, ZhaoWei; Pecht, Michael G

    2014-01-01

    This critical volume provides an in-depth presentation of copper wire bonding technologies, processes and equipment, along with the economic benefits and risks.  Due to the increasing cost of materials used to make electronic components, the electronics industry has been rapidly moving from high cost gold to significantly lower cost copper as a wire bonding material.  However, copper wire bonding has several process and reliability concerns due to its material properties.  Copper Wire Bonding book lays out the challenges involved in replacing gold with copper as a wire bond material, and includes the bonding process changes—bond force, electric flame off, current and ultrasonic energy optimization, and bonding tools and equipment changes for first and second bond formation.  In addition, the bond–pad metallurgies and the use of bare and palladium-coated copper wires on aluminum are presented, and gold, nickel and palladium surface finishes are discussed.  The book also discusses best practices and re...

  14. A new general and rapid method for investigating hot corrosion: preliminary tests on electrodes for molten carbonate fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Griffiths, T.R. [Dept. of Chemistry, Univ. of Leeds, Leeds (United Kingdom); Volkovich, V.A. [Dept. of Rare Metals, Ural State Technical Univ. - UPI, Ekaterinburg (Russian Federation)

    2004-07-01

    With the increase and improvement in corrosion resistant alloys, coatings and surface treatments, the ability to test and predict their long-term behaviour to oxidation under hot corrosion conditions, within a reasonable time period, becomes diminished. Peroxide and superoxide ions are the most active oxidisers and we have established a means for generating them in significant concentrations in molten carbonates. This thus has the potential for enabling accelerated hot corrosion studies and we here describe the technique and report preliminary studies on the nickel and nickel oxide electrodes used in molten carbonate fuel cells. Further applications are expected to follow. (orig.)

  15. Research regarding stiffness optimization of wires used for joints actuation from an elephant's trunk robotic arm

    Science.gov (United States)

    Ciofu, C.; Stan, G.

    2016-11-01

    Elephant's trunk robotic arms driven by wires and pulley mechanisms have issues with wires stiffness because of the entailed elastic deformations that is causing errors of positioning. Static and dynamic loads from each joint of the robotic arm affect the stiffness of driving wires and precision positioning. The influence of wires elastic deformation on precision positioning decreases with the increasing of wires stiffness by using different pre-tensioning devices. In this paper, we analyze the variation of driving wires stiffness particularly to each wire driven joint. We obtain optimum wires stiffness variation by using an analytical method that highlights the efficiency of pre-tensioning mechanism. The analysis of driving wires stiffness is necessary for taking appropriate optimization measures of robotic arm dynamic behavior and, thus, for decreasing positioning errors of the elephant's trunk robotic arm with inner actuation through wires/cables.

  16. 10 CFR 431.106 - Uniform test method for the measurement of energy efficiency of commercial water heaters and hot...

    Science.gov (United States)

    2010-01-01

    ... heaters). 431.106 Section 431.106 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY... of energy efficiency of commercial water heaters and hot water supply boilers (other than commercial...) Testing and Calculations. Determine the energy efficiency of each covered product by conducting the test...

  17. A method for manufacturing a tool part for an injection molding process, a hot embossing process, a nano-imprint process, or an extrusion process

    DEFF Research Database (Denmark)

    2013-01-01

    The present invention relates to a method for manufacturing a tool part for an injection molding process, a hot embossing process, nano-imprint process or an extrusion process. First, there is provided a master structure (10) with a surface area comprising nanometre-sized protrusions (11) with a ......The present invention relates to a method for manufacturing a tool part for an injection molding process, a hot embossing process, nano-imprint process or an extrusion process. First, there is provided a master structure (10) with a surface area comprising nanometre-sized protrusions (11...... of manufacturing the master structure, e.g. a black silicon wafer. It is a further advantage of the present invention that it provides an advantageous way of making tools capable of producing self-cleaning surfaces without the need for chemical coating....

  18. A comparison of a 'J' wire and a straight wire in successful antegrade cannulation of the superficial femoral artery

    Energy Technology Data Exchange (ETDEWEB)

    Gay, D.A.T. [Department of Radiology, Derriford Hospital, Plymouth (United Kingdom); Edwards, A.J. [Department of Radiology, Derriford Hospital, Plymouth (United Kingdom); Puckett, M.A. [Department of Radiology, Derriford Hospital, Plymouth (United Kingdom); Roobottom, C.A. [Department of Radiology, Derriford Hospital, Plymouth (United Kingdom)

    2005-01-01

    AIMS: To evaluate the success of two different types of wire in common use in their ability to successfully cannulate the superficial femoral artery (SFA) using antegrade puncture. METHODS: 50 consecutive patients in whom antegrade infra-inguinal intervention was planned, underwent common femoral arterial puncture and then cannulation with either a standard 3 mm 'J' wire or a floppy tipped straight wire (William Cook--Europe). The frequency with which each type of wire entered the SFA or profunda femoris artery without image guidance was recorded. Further analysis was also made of the success of manipulation of the wire into the SFA following profunda cannulation and the use of alternative guide wires. RESULTS: In 19 out of 25 (76%) patients the 'J' wire correctly entered the SFA without image guidance. Only 5 out of 25 (25%) of straight wires entered the SFA with the initial pass (p<0.0001). Following further manipulation with the same wire all except 1 'J' wire was successfully negotiated into the SFA. The same was true for only 9 of the remaining straight wires with 11 patients requiring an alternative guide wire. CONCLUSIONS: When performing antegrade cannulation of the SFA a 'J' wire is more likely to be successful than a straight guide wire.

  19. Wire core reactor for NTP

    Science.gov (United States)

    Harty, R. B.

    1991-01-01

    The development of the wire core system for Nuclear Thermal Propulsion (NTP) that took place from 1963 to 1965 is discussed. A wire core consists of a fuel wire with spacer wires. It's an annular flow core having a central control rod. There are actually four of these, with beryllium solid reflectors on both ends and all the way around. Much of the information on the concept is given in viewgraph form. Viewgraphs are presented on design details of the wire core, the engine design, engine weight vs. thrust, a technique used to fabricate the wire fuel element, and axial temperature distribution.

  20. Modern wiring practice

    CERN Document Server

    Steward, W E

    2012-01-01

    Continuously in print since 1952, Modern Wiring Practice has now been fully revised to provide an up-to-date source of reference to building services design and installation in the 21st century. This compact and practical guide addresses wiring systems design and electrical installation together in one volume, creating a comprehensive overview of the whole process for contractors and architects, as well as electricians and other installation engineers. Best practice is incorporated throughout, combining theory and practice with clear and accessible explanation, all

  1. Wiring and lighting

    CERN Document Server

    Kitcher, Chris

    2013-01-01

    Wiring and Lighting provides a comprehensive guide to DIY wiring around the home. It sets out the regulations and legal requirements surrounding electrical installation work, giving clear guidelines that will enable the reader to understand what electrical work they are able to carry out, and what the testing and certification requirements are once the work is completed. Topics covered include: Different types of circuits; Types of cables and cable installation under floors and through joists; Isolating, earthing and bonding; Accessory boxes and fixings; Voltage bands; Detailed advice on safe

  2. Method of the steel aluminum wires protection of air transmission lines from fast vibration damage at the output from the support clamp

    Science.gov (United States)

    Sabitov, L. S.; Kashapov, N. F.; Strelkov, Yu M.; Kuznetsov, I. L.

    2017-09-01

    Conducted theoretical research of the stress-strain state of flexible mechanical connections, the varieties of which are wires of overhead transmission lines, cable cable mounting structures, strings frequency sensors of force and small displacements at the nodes of a rigid fixing. Chosen form of nodules, a flexible mechanical connection at the nodes of the rigid fixing of the conditions of increasing resource durability, and also reduce the maximum total stresses from stretching and bending at the nodes of a rigid fixing.

  3. Hot spots

    National Research Council Canada - National Science Library

    Nia, Amir M; Gassanov, Natig; Er, Fikret

    2014-01-01

    ..., several reddened skin lesions were observed. The obvious ''hot spots'' were located on both sides in the groin and above the bladder, with extension to the genital region, compli- cating the ability to catheterize the patient (Figure 1). The rest of the body surface was not affected, and no infectious source for the skin lesions was evident. After suc...

  4. Kirschner Wire Fixation for the Treatment of Comminuted Zygomatic Fractures

    Science.gov (United States)

    Kang, Dai-Hun; Jung, Dong-Woo; Kim, Yong-Ha; Kim, Tae-Gon; Lee, JunHo

    2015-01-01

    Background The Kirschner wire (K-wire) technique allows stable fixation of bone fragments without periosteal dissection, which often lead to bone segment scattering and loss. The authors used the K-wire fixation to simplify the treatment of laborious comminuted zygomatic bone fracture and report outcomes following the operation. Methods A single-institution retrospective review was performed for all patients with comminuted zygomatic bone fractures between January 2010 and December 2013. In each patient, the zygoma was reduced and fixed with K-wire, which was drilled from the cheek bone and into the contralateral nasal cavity. For severely displaced fractures, the zygomaticofrontal suture was first fixated with a microplate and the K-wire was used to increase the stability of fixation. Each wire was removed approximately 4 weeks after surgery. Surgical outcomes were evaluated for malar eminence, cheek symmetry, Kwire site scar, and complications (based on a 4-point scale from 0 to 3, where 0 point is 'poor' and 3 points is 'excellent'). Results The review identified 25 patients meeting inclusion criteria (21 men and 4 women). The mean age was 52 years (range, 15-73 years). The mean follow up duration was 6.2 months. The mean operation time was 21 minutes for K-wire alone (n=7) and 52 minutes for K-wire and plate fixation (n=18). Patients who had received K-wire only fixation had severe underlying diseases or accompanying injuries. The mean postoperative evaluation scores were 2.8 for malar contour and 2.7 for K-wire site scars. The mean patient satisfaction was 2.7. There was one case of inflammation due to the K-wire. Conclusion The use of K-wire technique was associated with high patient satisfaction in our review. K-wire fixation technique is useful in patient who require reduction of zygomatic bone fractures in a short operating time. PMID:28913236

  5. Thermal Adaptation Methods of Urban Plaza Users in Asia's Hot-Humid Regions: A Taiwan Case Study.

    Science.gov (United States)

    Wu, Chen-Fa; Hsieh, Yen-Fen; Ou, Sheng-Jung

    2015-10-27

    Thermal adaptation studies provide researchers great insight to help understand how people respond to thermal discomfort. This research aims to assess outdoor urban plaza conditions in hot and humid regions of Asia by conducting an evaluation of thermal adaptation. We also propose that questionnaire items are appropriate for determining thermal adaptation strategies adopted by urban plaza users. A literature review was conducted and first hand data collected by field observations and interviews used to collect information on thermal adaptation strategies. Item analysis--Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA)--were applied to refine the questionnaire items and determine the reliability of the questionnaire evaluation procedure. The reliability and validity of items and constructing process were also analyzed. Then, researchers facilitated an evaluation procedure for assessing the thermal adaptation strategies of urban plaza users in hot and humid regions of Asia and formulated a questionnaire survey that was distributed in Taichung's Municipal Plaza in Taiwan. Results showed that most users responded with behavioral adaptation when experiencing thermal discomfort. However, if the thermal discomfort could not be alleviated, they then adopted psychological strategies. In conclusion, the evaluation procedure for assessing thermal adaptation strategies and the questionnaire developed in this study can be applied to future research on thermal adaptation strategies adopted by urban plaza users in hot and humid regions of Asia.

  6. Thermal Adaptation Methods of Urban Plaza Users in Asia’s Hot-Humid Regions: A Taiwan Case Study

    Science.gov (United States)

    Wu, Chen-Fa; Hsieh, Yen-Fen; Ou, Sheng-Jung

    2015-01-01

    Thermal adaptation studies provide researchers great insight to help understand how people respond to thermal discomfort. This research aims to assess outdoor urban plaza conditions in hot and humid regions of Asia by conducting an evaluation of thermal adaptation. We also propose that questionnaire items are appropriate for determining thermal adaptation strategies adopted by urban plaza users. A literature review was conducted and first hand data collected by field observations and interviews used to collect information on thermal adaptation strategies. Item analysis—Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA)—were applied to refine the questionnaire items and determine the reliability of the questionnaire evaluation procedure. The reliability and validity of items and constructing process were also analyzed. Then, researchers facilitated an evaluation procedure for assessing the thermal adaptation strategies of urban plaza users in hot and humid regions of Asia and formulated a questionnaire survey that was distributed in Taichung’s Municipal Plaza in Taiwan. Results showed that most users responded with behavioral adaptation when experiencing thermal discomfort. However, if the thermal discomfort could not be alleviated, they then adopted psychological strategies. In conclusion, the evaluation procedure for assessing thermal adaptation strategies and the questionnaire developed in this study can be applied to future research on thermal adaptation strategies adopted by urban plaza users in hot and humid regions of Asia. PMID:26516881

  7. Thermal Adaptation Methods of Urban Plaza Users in Asia’s Hot-Humid Regions: A Taiwan Case Study

    Directory of Open Access Journals (Sweden)

    Chen-Fa Wu

    2015-10-01

    Full Text Available Thermal adaptation studies provide researchers great insight to help understand how people respond to thermal discomfort. This research aims to assess outdoor urban plaza conditions in hot and humid regions of Asia by conducting an evaluation of thermal adaptation. We also propose that questionnaire items are appropriate for determining thermal adaptation strategies adopted by urban plaza users. A literature review was conducted and first hand data collected by field observations and interviews used to collect information on thermal adaptation strategies. Item analysis—Exploratory Factor Analysis (EFA and Confirmatory Factor Analysis (CFA—were applied to refine the questionnaire items and determine the reliability of the questionnaire evaluation procedure. The reliability and validity of items and constructing process were also analyzed. Then, researchers facilitated an evaluation procedure for assessing the thermal adaptation strategies of urban plaza users in hot and humid regions of Asia and formulated a questionnaire survey that was distributed in Taichung’s Municipal Plaza in Taiwan. Results showed that most users responded with behavioral adaptation when experiencing thermal discomfort. However, if the thermal discomfort could not be alleviated, they then adopted psychological strategies. In conclusion, the evaluation procedure for assessing thermal adaptation strategies and the questionnaire developed in this study can be applied to future research on thermal adaptation strategies adopted by urban plaza users in hot and humid regions of Asia.

  8. Wiring for space applications program

    Science.gov (United States)

    Hammoud, Ahmad

    1994-01-01

    The insulation testing and analysis consists of: identifying and prioritizing NASA wiring requirements; selecting candidate wiring constructions; developing test matrix and formulating test program; managing, coordinating, and conducting tests; and analyzing and documenting data, establishing guidelines and recommendations.

  9. Debate: Wired versus Wireless.

    Science.gov (United States)

    Meeks, Glenn; Nair, Prakash

    2000-01-01

    Debates the issue of investing in wiring schools for desktop computer networks versus using laptops and wireless networks. Included are cost considerations and the value of technology for learning. Suggestions include using wireless networks for existing schools, hardwiring computers for new construction, and not using computers for elementary…

  10. Wired vs. Wireless.

    Science.gov (United States)

    Fielding, Randall

    2000-01-01

    Presents a debate on which technology will be in tomorrow's classrooms and the pros and cons of wiring classrooms and using a wireless network. Concluding comments address the likelihood, and desirability, of placing computers throughout the entire educational process and what types of computers and capabilities are needed. (GR)

  11. Wired to freedom

    DEFF Research Database (Denmark)

    Jepsen, Kim Sune Karrasch; Bertilsson, Margareta

    2017-01-01

    dimension of life science through a notion of public politics adopted from the political theory of John Dewey. We show how cochlear implantation engages different social imaginaries on the collective and individual levels and we suggest that users share an imaginary of being “wired to freedom” that involves...

  12. Gaseous wire detectors

    Energy Technology Data Exchange (ETDEWEB)

    Va' vra, J.

    1997-08-01

    This article represents a series of three lectures describing topics needed to understand the design of typical gaseous wire detectors used in large high energy physics experiments; including the electrostatic design, drift of electrons in the electric and magnetic field, the avalanche, signal creation, limits on the position accuracy as well as some problems one encounters in practical operations.

  13. 3D Wire 2015

    DEFF Research Database (Denmark)

    Jordi, Moréton; F, Escribano; J. L., Farias

    This document is a general report on the implementation of gamification in 3D Wire 2015 event. As the second gamification experience in this event, we have delved deeply in the previous objectives (attracting public areas less frequented exhibition in previous years and enhance networking) and have...

  14. Practical wiring in SI units

    CERN Document Server

    Miller, Henry A

    2013-01-01

    Practical Wiring, Volume 1 is a 13-chapter book that first describes some of the common hand tools used in connection with sheathed wiring. Subsequent chapters discuss the safety in wiring, cables, conductor terminations, insulating sheathed wiring, conductor sizes, and consumer's control equipments. Other chapters center on socket outlets, plugs, lighting subcircuits, lighting accessories, bells, and primary and secondary cells. This book will be very valuable to students involved in this field of interest.

  15. Comparison of techniques for the measurement of skin temperature during exercise in a hot, humid environment

    Directory of Open Access Journals (Sweden)

    Brian K McFarlin

    2014-10-01

    Full Text Available Exercising or working in a hot, humid environment can results in the onset of heat-related illness when an individual’s temperature is not carefully monitored. The purpose of the present study was to compare three techniques (data loggers, thermal imaging, and wired electrodes for the measurement of peripheral (bicep and central (abdominal skin temperature. Young men and women (N=30 were recruited to complete the present study. The three skin temperature measurements were made at 0 and every 10-min during 40-min (60% VO 2 max of cycling in a hot (39±2°C, humid (45±5% RH environment. Data was statistically analyzed using the Bland-Altman method and correlation analysis. For abdominal skin temperature, the Bland-Altman limits of agreement indicated that data loggers (1.5 were a better index of wired than was thermal imaging (3.5, For the bicep skin temperature the limits of agreement was similar between data loggers (1.9 and thermal (1.9, suggesting the both were suitable measurements. We also found that when skin temperature exceeded 35ºC, we observed progressively better prediction between data loggers, thermal imaging, and wired skin sensors. This report describes the potential for the use of data loggers and thermal imaging to be used as alternative measures of skin temperature in exercising, human subjects

  16. Temperature Dependent Wire Delay Estimation in Floorplanning

    DEFF Research Database (Denmark)

    Winther, Andreas Thor; Liu, Wei; Nannarelli, Alberto

    2011-01-01

    Due to large variations in temperature in VLSI circuits and the linear relationship between metal resistance and temperature, the delay through wires of the same length can be different. Traditional thermal aware floorplanning algorithms use wirelength to estimate delay and routability....... In this work, we show that using wirelength as the evaluation metric does not always produce a floorplan with the shortest delay. We propose a temperature dependent wire delay estimation method for thermal aware floorplanning algorithms, which takes into account the thermal effect on wire delay. The experiment...... results show that a shorter delay can be achieved using the proposed method. In addition, we also discuss the congestion and reliability issues as they are closely related to routing and temperature....

  17. HOT 2017

    DEFF Research Database (Denmark)

    Hannibal, Sara Stefansen

    HOT er en kvalitativ undersøgelse, der hvert år diskuterer og undersøger en lille udvalgt skare af danskkyndige fagpersoners bud på, hvad de er optagede af på literacyområdet her og nu – altså hvilke emner, de vil vurdere som aktuelle at forholde sig til i deres nuværende praksis....

  18. Study of Hot Salt Stress Corrosion Crack Initiation of Alloy IMI 834 by using DC Potential Drop Method

    Energy Technology Data Exchange (ETDEWEB)

    Pustode, Mangesh D. [Bharat Forge Ltd., Pune (India); Dewangan, Bhupendra [Tata Steel, Jamshedpur (India); Raja, V. S. [Indian Institute of Technology Bombay, Mumbai (India); Paulose, Neeta; Babu, Narendra [Gas Turbine Research Establishment (GTRE), Bangalore (India)

    2016-10-15

    DC potential drop technique was employed during the slow strain rate tests to study the hot salt stress corrosion crack (HSSCC) initiation at 300 and 400 ℃. Threshold stresses for HSSCC initiation were found to about 88 % of the yield strength at both temperatures, but the time from crack initiation to final failure (Δtscc) decreased significantly with temperature, which reflects larger tendency for brittle fracture and secondary cracking. The brittle fracture features consisted of transgranular cracking through the primary α grain and discontinuous faceted cracking through the transformed β grains.

  19. Iinvestigation by electrocontact method of interaction of water with hot surface in film and transition boiling regimes

    Science.gov (United States)

    Ivochkin, Y. P.; Kubrikov, K. G.; Sinkevich, O. A.; Zeigarnik, Y. A.

    2017-11-01

    Using the conductometric technique, the process of contact of subcooled distilled water with a hot surface was studied. The results of measurements of the parameters of the contact made in the range of the temperature change of the heated surface 170 ± 620 ° C are given. An experimental fact has been revealed, which indicates that a transition from film to bubble boiling is preceded by a short (several millisecond) hydrodynamic process that is characterized by intense interaction of waves at the vapour - liquid interface with the heated surface. With the help of wavelet analysis, the amplitude-frequency characteristics of this process are investigated and a qualitative physical model of its flow

  20. [Design and experiment of guide wire tele-manipulation system based on laser mouse sensor].

    Science.gov (United States)

    Shen, Jie; Li, Shenglin; Chen, Daguo; Yan, Yonghua

    2012-01-01

    In order to realize the guide wire tele-manipulation in intervention operation, a method for guide wire motion detection with laser mouse sensor is proposed and experiments are carried out. On that basis, a guide wire tele-manipulation system which consists of guide wire detection appliance, guide wire manipulation appliance, and master slave type software is designed. Experiments are conducted on the system and acquired needed data, so that relationships between operating time and the distance from guide wire tip to destination and the angle are analyzed. The results validate the feasibility of the system and provide good foundation for future research.

  1. Evaluation of the accuracy of a veterinary dynamometric wire tensioner.

    Science.gov (United States)

    Gauthier, C M; McGilvray, K; Myrick, S; Duerr, F; Palmer, R

    2015-01-01

    The purpose of this study was to determine the accuracy of a commonly used veterinary wire tensioner. Wire tension was measured using a load cell after each of five tensioners were used to tension each of six wires to the 66, 84, and 118 mm ring settings in an adjustable custom testing fixture. Each tensioner then experienced simulated aging and testing was repeated. Percentage error was calculated for each ring size, before and after tensioner aging. Measured tension values were compared to manufacturer reported tension values for each ring size using a one-sample two-way t-test; p tension values were significantly lower for 66 mm and 84 mm rings and significantly higher for 118 mm rings, before and after simulated aging. Mean wire tension values did not significantly differ between individual wire tensioners. The tensioners tested achieved significantly different wire tension values than those reported by the manufacturer. This discrepancy could lead to under-tensioning and allowing excessive movement at a fracture site or over-tensioning, leading to wire breakage. We recommend tensioning wires at least to the recommended line on the device for 66 mm and 84 mm rings and at most to the recommended line for 118 mm rings. Further studies are needed to evaluate other veterinary wire tensioners and to develop a calibration method for these devices in practice.

  2. Integrated Electrical Wire Insulation Repair System

    Science.gov (United States)

    Williams, Martha; Jolley, Scott; Gibson, Tracy; Parks, Steven

    2013-01-01

    An integrated system tool will allow a technician to easily and quickly repair damaged high-performance electrical wire insulation in the field. Low-melt polyimides have been developed that can be processed into thin films that work well in the repair of damaged polyimide or fluoropolymer insulated electrical wiring. Such thin films can be used in wire insulation repairs by affixing a film of this low-melt polyimide to the damaged wire, and heating the film to effect melting, flow, and cure of the film. The resulting repair is robust, lightweight, and small in volume. The heating of this repair film is accomplished with the use of a common electrical soldering tool that has been modified with a special head or tip that can accommodate the size of wire being repaired. This repair method can furthermore be simplified for the repair technician by providing replaceable or disposable soldering tool heads that have repair film already "loaded" and ready for use. The soldering tool heating device can also be equipped with a battery power supply that will allow its use in areas where plug-in current is not available

  3. Thermal stability of hot-wire deposited amorphous silicon

    CSIR Research Space (South Africa)

    Arendse, CJ

    2006-04-01

    Full Text Available of vacancy clustering at 400 -C, caused by the alignment of unterminated Si dangling-bonds that consequently results in an increase in the defect size, concentration or both. Raman scattering shows evidence that no crystallization is induced at 400 -C...

  4. Hot-wire chemical vapour deposition of carbon nanotubes

    CSIR Research Space (South Africa)

    Cummings, FR

    2006-07-01

    Full Text Available Owing entirely to their structure, carbon nanotubes (CNTs) possess some of the most remarkable chemical and physical properties. More specifically, they exhibit exceptional strength and toughness, chemical inertness, magnetism, and electrical...

  5. Obelix Wire Chamber

    CERN Multimedia

    1986-01-01

    Two wire chambers made originally for the R807 Experiment at CERN's Intersecting Storage Rings. In 1986 they were used for the PS 201 experiment (Obelix Experiment) at LEAR, the Low Energy Antiproton Ring. The group of researchers from Turin, using the chambers at that time, changed the acquisition system using for the first time 8 bit (10 bit non linear) analog to digital conversion for incoming signals from the chambers. The acquisition system was controlled by 54 CPU and 80 digital signal processors. The power required for all the electronics was 40 kW. For the period, this system was one of the most powerful on-line apparatus in the world. The Obelix Experiment was closed in 1996. To find more about how a wire chamber works, see the description for object CERN-OBJ-DE-038.

  6. Study on unified fatigue strength assessment method for welded structure. Hot spot stress evaluating method for various combinations of plate thickness and weld leg length; Yosetsu kozo no toitsutekina hiro kyodo hyokaho ni kansuru kenkyu. Itaatsu to yosetsu ashinaga no kumiawase ni taisuru hot spot oryoku sanshutsu ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Nihei, K.; Inamura, F.; Koe, S. [Kawasaki Heavy Industries, Ltd., Kobe (Japan)

    1996-12-31

    There has been tried to apply unified assessment method using hot spot stress, which is effective to evaluate fatigue strength of fillet welded structures for ships and marine structures. This method can be applied to complicated structures and is independent of welding processes. In this study, first, stress analysis has been conducted for two-dimensional fillet welded joint models with various combinations of plate thickness and weld leg length of general fillet structures by means of boundary element method. Then, critical position, which is not affected by local stress concentration due to bead, was determined from the detailed stress distribution in the vicinity of weld toe. As a result, a general equation has been proposed to estimate the hot spot stress by one-point representative method. Second, the fatigue tests of typical fillet welded joints have been conducted by applying this method. Consequently, it was demonstrated that the unified fatigue strength can be evaluated by the S-N data based on hot spot stress range determined from the proposed equation, independent of structural stress concentration. 22 refs., 14 figs.

  7. Command Wire Sensor Measurements

    Science.gov (United States)

    2012-09-01

    NPS anechoic chamber is located in Spanagel Hall, Room 604. Although the chamber was built for instruction purposes only, it can be used for research...thesis is to investigate the wire scattering behavior and clutter characteristics through measurements performed in the NPS anechoic chamber. The...research has successfully resolved the various multipath components within the anechoic chamber. The transmit-receive coupling between the antennas was

  8. Forecasting of Corrosion Properties of Steel Wires for Production of Guide Wires for Cardiological Treatment

    Directory of Open Access Journals (Sweden)

    J. Przondziono

    2013-01-01

    Full Text Available The study presents evaluation of the influence of strain in drawing process and of surface modification on resistance to electrochemical corrosion of wires made of stainless steel for production of guide wires used in invasive cardiology. The results of static tensile test enabled us to determine the course of flow curve of wires made of X10CrNi 18-8 steel as well as mathematical form of flow stress function. Resistance to electrochemical corrosion was evaluated on the ground of registered anodic polarisation curves by means of potentiodynamic method. The tests were performed in solution simulating human blood on samples that were electrolytically polished and samples that were polished and then chemically passivated. Exemplary anodic polarisation curves were given. It was proved that with the applied strain, corrosion properties decrease. It was found that chemical passivation improves wire corrosion characteristics. Statistical analysis showed that there is a significant dependence between corrosion properties (polarisation resistance Rp and strain ε applied in drawing process. Functions that present the change Rp=f(ε were selected. The issue is of importance to guide wire manufacturers because application of the suggested methodology will enable us to forecast corrosion characteristics of wire with the required strength drawn with the applied strain.

  9. Wire grid polarizers for visible wavelengths

    Science.gov (United States)

    Johnson, Joshua Hans

    Detailed analysis of wire-grid (WG) polarizers for visible wavelengths is presented. Rigorous coupled-wave analysis (RCWA) is used to model their performance. The optimum choice of metal for the wires is identified, and the effects of different substrate indices of refraction are considered. The polarization properties are considered with changes in the physical parameters, including period, duty cycle, and wire thickness. It is shown that the performance of WG polarizers improves with increasing angle of incidence. The effect of non-square wire profiles is considered, as is the effect of adding additional dielectric layers between the wires and the substrate. The effect of metal oxide layers forming on the wires is also modeled. While most of this work concerns WG polarizers used in transmission, the performance in reflection is also discussed. Several visible-wavelength WG polarizers were fabricated at the Cornell Nanofabrication Facility (CNF) in Ithaca, NY. Electron-beam lithography was used to write the patterns for these devices, and two different methods of pattern transfer were compared. These were the lift-off method and reactive-ion etching (RIE). We found that lift-off could not produce wires thick enough for good polarization properties. RIE could produce much thicker wires with good profiles and was used for all of the experimental work presented here. Two different methods for metal film deposition, evaporation and sputtering were also compared. Films deposited by sputtering were found to have much lower indices of refraction and to not respond to etching as well. Thermally evaporated films performed much better in WG polarizers. Alternative methods for the mass-production of visible-wavelength WG polarizers are also discussed. The performance of the fabricated WG polarizers is compared to theory. When the measured physical parameters are used in RCWA to predict the performance, the measured extinction ratio is found to be much lower than the

  10. Evaluation of a new method for chemical coating of aluminum wire with molecularly imprinted polymer layer. Application for the fabrication of triazines selective solid-phase microextraction fiber

    Energy Technology Data Exchange (ETDEWEB)

    Djozan, Djavanshir, E-mail: djozan@tabrizu.ac.ir [Department of Analytical Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of); Ebrahimi, Bahram [Department of Analytical Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of); Mahkam, Mehrdad [Chemistry Department, Azarbaijan University of Tarbiat Moallem, Tabriz (Iran, Islamic Republic of); Farajzadeh, Mir Ali [Department of Analytical Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of)

    2010-07-26

    A new solid-phase microextraction (SPME) fiber is fabricated through ultra violet irradiation polymerization of ametryn-molecularly imprinted polymer on the surface of anodized-silylated aluminum wire. The prepared fiber is durable with very good chemical and thermal stability which can be coupled to GC and GC/MS. The effective parameters on the fabrication and application procedures such as spraying mode, ultra violet irradiation (polymerization) time, number of sprayings and polymerizations, pH and ionic strength of sample and extraction time were optimized. This fiber shows high selectivity with great extraction capacity toward triazines. SPME and GC analysis of ametryn, prometryn, terbutryn, atrazine, simazine, propazine and cyanazine using the fabricated fiber result in the detection limits of 9, 32, 27, 43, 51, 74 and 85 ng mL{sup -1}, respectively. The reliability of the prepared fiber in real samples has been investigated and proved by using spiked tap water, rice, maize and onion samples.

  11. Lignin Content in Xylan-Rich Lignocellulosic Species (Angiosperms) Before and After Hot-Water Extraction: Klason Lignin and Acetyl Bromide Methods

    Science.gov (United States)

    Jing, Chengyan

    Klason lignin is the most commonly used method of lignin content determination. However, it is time-consuming and consists of acid-insoluble and acid-soluble lignin fractions, resulting in potential errors during handling and calculations. This study investigated the use of a one-step UV-spectroscopy-based acetyl bromide method as a possible alternative. Four Angiosperms; sugar maple, willow, Miscanthus and wheat straw, suggested for use in biorefineries, were analyzed before and after hot-water extraction; autohydrolytic pretreatment. Different organic solvents were evaluated for removal of extractives prior to lignin analyses. Milled wood lignin (MWL) was prepared for each species to calibrate absorptivity used in the acetyl bromide lignin calculations. These studies demonstrated that the acetyl bromide method is reliable and may serve as an alternative to Klason lignin. The acetyl bromide lignin results corroborate well the Klason lignin results and the correlation is improved if the absorptivity determined on respective MWLs is used in calculations.

  12. Metering Wheel-Wire Track Wire Boom Deployment Mechanism

    Science.gov (United States)

    Granoff, Mark S.

    2014-01-01

    The NASA MMS Spin Plane Double Probe (SDP) Deployer utilizes a helical path, rotating Metering Wheel and a spring loaded Wire "Holding" Track to pay out a "fixed end" 57 meter x 1.5 mm diameter Wire Boom stored between concentric storage cylinders. Unlike rotating spool type storage devices, the storage cylinders remain stationary, and the boom wire is uncoiled along the length of the cylinder via the rotation of the Metering Wheel. This uncoiling action avoids the need for slip-ring contacts since the ends of the wire can remain stationary. Conventional fixed electrical connectors (Micro-D type) are used to terminate to operational electronics.

  13. The critical spot eraser-a method to interactively control the correction of local hot and cold spots in IMRT planning.

    Science.gov (United States)

    Süss, Philipp; Bortz, Michael; Küfer, Karl-Heinz; Thieke, Christian

    2013-03-21

    Common problems in inverse radiotherapy planning are localized dose insufficiencies like hot spots in organs at risk or cold spots inside targets. These are hard to correct since the optimization is based on global evaluations like maximum/minimum doses, equivalent uniform doses or dose-volume constraints for whole structures. In this work, we present a new approach to locally correct the dose of any given treatment plan. Once a treatment plan has been found that is acceptable in general but requires local corrections, these areas are marked by the planner. Then the system generates new plans that fulfil the local dose goals. Consequently, it is possible to interactively explore all plans between the locally corrected plans and the original treatment plan, allowing one to exactly adjust the degree of local correction and how the plan changes overall. Both the amount (in Gy) and the size of the local dose change can be navigated. The method is introduced formally as a new mathematical optimization setting, and is evaluated using a clinical example of a meningioma at the base of the skull. It was possible to eliminate a hot spot outside the target volume while controlling the dose changes to all other parts of the treatment plan. The proposed method has the potential to become the final standard step of inverse treatment planning.

  14. Randomized study of tolerance and efficacy of a home-use intense pulsed light (IPL) source compared to the hot-wax method.

    Science.gov (United States)

    Adhoute, Hertsel; Hamidou, Zohra; Humbert, Philippe; Lyonnet, Cindy; Peuchot, Marie-Anne; Reygagne, Pascal; Reynier, Chantal; Rivoire, Stéphanie; Simoneau, Guy; Toubel, Gerard

    2010-12-01

    More and more we are seeing depilatory mechanisms based on IPL technology and used at home. As far as we know, these appliance have not undergone either safety or efficacy testing. The aim of the study was to compare tolerance and efficacy of two depilation methods a medical device in-home-use IPL (E-One) and hot wax. Axillae of 63 persons were treated by either IPL (intense pulsed light) or hot wax for 49 weeks. Tolerance was assessed clinically by a dermatologist and efficacy by an independent blinded photographic assessment. Tolerance of the two methods is reasonably good with better results for the IPL treatment. IPL treatment is also much more efficient. This study confirmed good tolerance and excellent efficacy of this first one medical device used at home. Taking into consideration the mechanical action of the IPL and our experience, other cutaneous appliances (against wrinkles (or aging), hyperpigmentation. etc.) could be considered after optimization of the technical parameters. © 2010 Wiley Periodicals, Inc.

  15. Reduction in wire tension caused by wire clamping and wire tensioner removal: an experimental Ilizarov frame study.

    Science.gov (United States)

    La Russa, Valentina; Skallerud, Bjørn; Klaksvik, Jomar; Foss, Olav A

    2011-03-01

    The stability of an external ring fixator mainly depends on wire tension. Wire fixators should maintain the tension during both wire clamping to the ring and removal of the tensioner device. In the present study the loss in wire tension related to fixator clamping and wire tensioner removal using three different wire fixator designs was studied. The fixators were based on two different cannulated bolts and a washer. Effects from two different pretension levels in combination with three different bolt torque levels upon loss in wire tension were described. Emitted wire vibration frequency was used to assess the corresponding wire tension. Wire tension was determined after each wire fixator tightening and after the removal of the wire tensioner. Increased bolt torque led to a small decrease in tension for both pretension levels. A considerable higher tension loss was measured when removing the wire tensioner. In all cases, the combination of a new cannulated bolt and a washer maintained the highest tension.

  16. Review of wire chamber aging

    Energy Technology Data Exchange (ETDEWEB)

    Va' Vra, J.

    1986-02-01

    This paper makes an overview of the wire chamber aging problems as a function of various chamber design parameters. It emphasizes the chemistry point of view and many examples are drawn from the plasma chemistry field as a guidance for a possible effort in the wire chamber field. The paper emphasizes the necessity of variable tuning, the importance of purity of the wire chamber environment, as well as it provides a practical list of presently known recommendations. In addition, several models of the wire chamber aging are qualitatively discussed. The paper is based on a summary talk given at the Wire Chamber Aging Workshop held at LBL, Berkeley on January 16-17, 1986. Presented also at Wire Chamber Conference, Vienna, February 25-28, 1986. 74 refs., 18 figs., 11 tabs.

  17. Mixed and dynamic response of hot wires and cold wires and measurements of turbulence statistics

    DEFF Research Database (Denmark)

    Larsen, Søren Ejling; Højstrup, Jørgen; Fairall, C. W.

    1986-01-01

    . The influence of the transfer characteristics on measurements of turbulence statistics is discussed; it is shown that the nonideal response behavior influences, most strongly, statistics involving the correlation between velocity and temperature and, most seriously, parameters involving small-scale turbulence...

  18. Wiring regulations in brief

    CERN Document Server

    Tricker, Ray

    2012-01-01

    Tired of trawling through the Wiring Regs?Perplexed by Part P?Confused by cables, conductors and circuits?Then look no further! This handy guide provides an on-the-job reference source for Electricians, Designers, Service Engineers, Inspectors, Builders, Students, DIY enthusiastsTopic-based chapters link areas of working practice - such as cables, installations, testing and inspection, special locations - with the specifics of the Regulations themselves. This allows quick and easy identification of the official requirements relating to the situati

  19. Effect of Microstructure on the Hot Deformation Behavior of TiAl-Based Alloys Prepared by Powder Metallurgy Method

    Science.gov (United States)

    Wang, DongJun; Zhang, Rui; Yuan, Hao; Qiang, JianMing

    2017-10-01

    To investigate microstructural influence on deformation behavior, TiAl-based alloys were prepared by spark plasma sintering and heat treatment was conducted to optimize the microstructures of as-sintered samples. The near-γ microstructure of the sintered alloy transformed into a duplex microstructure after heat treatment. Furthermore, isothermal compression tests were carried out at different temperatures in the range 1100-1200°C with a strain rate of 0.01 s-1. The resistances to deformation of the heat-treated samples were smaller than those of the as-sintered samples under the same deformation conditions. In particular, the heat-treated sample had fewer and smaller α2 phases than did the sintered alloy, and it exhibited a well-deformed appearance and homogeneous microstructure after deformation at a temperature 100°C lower than the sintered alloy. The results revealed that TiAl-based alloys with an optimal microstructure fabricated by powder metallurgy had good formability and a homogeneous deformed microstructure, which was preferable for hot-working and further secondary processing.

  20. A comparative simple method for human bioclimatic conditions applied to seasonally hot/warm cities of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Tejeda Martinez, A. [Universidad Veracruzana, Xalapa, Veracruz (Mexico); Garcia Cueto, O.R. [Universidad Autonoma de Baja California, Mexicali, B.C. (Mexico)

    2002-01-01

    The climate of a region is an environmental resource with important implications for things such as thermal comfort, health and productivity of the population. In this work, the bioclimatic comfort was evaluated for seven seasonally warm/hot cities of Mexico by means of the following current indexes: Discomfort Index, Enthalpy Index and Heat Strain Index. Also, the periods during which it is necessary to use air conditioning in the studied cities were calculated from estimated global radiation and hourly data of temperature and relative humidity which made it possible to establish them with high precision. Finally, the useful of the Heat Strain Index is shown. It is a simple index needing available meteorological data to compare bioclimatic conditions of similar sites. [Spanish] El clima regional tiene implicaciones en el confort, la salud y la productividad de la poblacion. En este articulo se presentan las evaluaciones bioclimaticas comparativas de siete ciudades calidas de Mexico. Se aplicaron los indices bioclimaticos de disconfort, entalpia y esfuerzo frente al calor. Se calcularon los periodos para los cuales es necesario el uso de aire acondicionado, a partir de estimaciones de radiacion solar global y de temperatura y humedad horarias medias mensuales. Finalmente se muestra la utilidad y calidad del Indice de esfuerzo frente al calor, el cual requiere solo de datos climatologicos comunes para poder comparar condiciones bioclimaticas de sitios similares.

  1. A novel method of utilization of hot dip galvanizing slag using the heat waste from itself for protection from radiation.

    Science.gov (United States)

    Dong, Mengge; Xue, Xiangxin; Kumar, Ashok; Yang, He; Sayyed, M I; Liu, Shan; Bu, Erjun

    2018-02-15

    A novel, unconventional, low cost, eco-friendly and effective shielding materials have been made utilizing the hot dip galvanizing slag using the heat waste from itself, thereby saving the natural resources and preventing the environmental pollution. SEM-EDS of shielding materials indicates that the other elements are distributed in Zn element. The mass attenuation properties of shielding materials were measured using a narrow beam geometrical setup at 0.662MeV, 1.17MeV and 1.33MeV. The half value thickness layer, effective atomic number, and electron density were used to analyze the shielding performance of the materials. The EBFs and EABFs for the prepared shielding materials were also studied with incident photon energy for penetration depths upto 40mfp. The shielding effectiveness has been compared with lead, iron, zinc, some standard shielding concretes, different glasses and some alloys. The shielding effectiveness of the prepared samples is almost found comparable to iron, zinc, selected alloys and glasses while better than some standard shielding concretes. In addition, it is also found that the bending strength of all shielding materials is more than 110MPa. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Torque resistance of different stainless steel wires commonly used for fixed retainers in orthodontics

    DEFF Research Database (Denmark)

    Arnold, Dario; Dalstra, Michel; Verna, Carlalberta

    2016-01-01

    retainers in orthodontics. Materials and Methods: Torquing moments acting on a retainer wire were measured in a mechanical force testing system by applying buccal crown torque to an upper lateral incisor in both a 3-teeth and in a 2-teeth setup. Seven stainless steel wires with different shape, type (plain......Objective: Movements of teeth splinted by fixed retention wires after orthodontic treatment have been observed. The aetiological factors for these movements are unknown. The aim of this in vitro study was to compare the resistance to torque of different stainless steel wires commonly used for fixed...... or a braided 0.016 × 0.022-inch stainless steel wire. A tooth attached by a retainer wire to only one neighbouring tooth is less resistant to torque than a tooth connected to two neighbouring teeth. Annealing a retainer wire with a flame reduces the stiffness of the wire markedly and can lead to a non...

  3. Effects of hot air and freeze drying methods on antioxidant activity, colour and some nutritional characteristics of strawberry tree (Arbutus unedo L) fruit.

    Science.gov (United States)

    Orak, H H; Aktas, T; Yagar, H; İsbilir, S Selen; Ekinci, N; Sahin, F Hasturk

    2012-08-01

    Antioxidant activity, colour and some nutritional properties of hot air and freeze-dried strawberry tree (Arbutus unedo L.) fruits were investigated. Additionally, the effects of two pre-treatments, namely ethyl oleate and water blanching, were compared in terms of drying characteristics. For determination of antioxidant activities in ethanol extracts, two different analytical methods were used: 1,1-diphenyl-2-picrylhydrazyl scavenging activity and β-carotene bleaching activity. As a result, the ethyl oleate pre-treatment shortened the drying time by hot air method and gave a higher 1,1-diphenyl-2-picrylhydrazyl scavenging activity (82.16 ± 0.34%), total phenolic content (7.62 ± 1.09 µg GAE/g extract), ascorbic acid content (236.93 ± 20.14 mg/100 g), besides hydromethylfurfural was not observed. Freeze-dried fruits exhibited higher ascorbic acid content (368.63 ± 17.16 mg/100 g) than those fresh fruits (231.33 ± 19.51 mg/100 g) and nearly 1,1-diphenyl-2-picrylhydrazyl activity (93.52 ± 0.41 %) to fresh fruits (94.03 ± 1.18%). Colour characteristics, sugar content and mineral contents of fruits were significantly affected by pre-treatments and drying methods (p drying of strawberry tree fruits should bring a valuable and attractive foodstuff to food industry due to the rich nutritional components, antioxidant activity and colour. Another conclusion from this study is that the freeze-drying is the best drying method to keep the nutritional value, antioxidant activity and sensory properties of fruits.

  4. Low-Cost and Rapid Fabrication of Metallic Nanostructures for Sensitive Biosensors Using Hot-Embossing and Dielectric-Heating Nanoimprint Methods

    Directory of Open Access Journals (Sweden)

    Kuang-Li Lee

    2017-07-01

    Full Text Available We propose two approaches—hot-embossing and dielectric-heating nanoimprinting methods—for low-cost and rapid fabrication of periodic nanostructures. Each nanofabrication process for the imprinted plastic nanostructures is completed within several seconds without the use of release agents and epoxy. Low-cost, large-area, and highly sensitive aluminum nanostructures on A4 size plastic films are fabricated by evaporating aluminum film on hot-embossing nanostructures. The narrowest bandwidth of the Fano resonance is only 2.7 nm in the visible light region. The periodic aluminum nanostructure achieves a figure of merit of 150, and an intensity sensitivity of 29,345%/RIU (refractive index unit. The rapid fabrication is also achieved by using radio-frequency (RF sensitive plastic films and a commercial RF welding machine. The dielectric-heating, using RF power, takes advantage of the rapid heating/cooling process and lower electric power consumption. The fabricated capped aluminum nanoslit array has a 5 nm Fano linewidth and 490.46 nm/RIU wavelength sensitivity. The biosensing capabilities of the metallic nanostructures are further verified by measuring antigen–antibody interactions using bovine serum albumin (BSA and anti-BSA. These rapid and high-throughput fabrication methods can benefit low-cost, highly sensitive biosensors and other sensing applications.

  5. Corrosion of Wires on Wooden Wire-Bound Packaging Crates

    Science.gov (United States)

    Samuel L. Zelinka; Stan Lebow

    2015-01-01

    Wire-bound packaging crates are used by the US Army to transport materials. Because these crates may be exposed to harsh environments, they are dip-treated with a wood preservative (biocide treatment). For many years, zinc-naphthenate was the most commonly used preservative for these packaging crates and few corrosion problems with the wires were observed. Recently,...

  6. Development and testing of a photometric method to identify non-operating solar hot water systems in field settings.

    Energy Technology Data Exchange (ETDEWEB)

    He, Hongbo (University of New Mexico, Albuquerque, NM); Vorobieff, Peter V. (University of New Mexico, Albuquerque, NM); Menicucci, David (University of New Mexico, Albuquerque, NM); Mammoli, Andrea A. (University of New Mexico, Albuquerque, NM); Carlson, Jeffrey J.

    2012-06-01

    This report presents the results of experimental tests of a concept for using infrared (IR) photos to identify non-operational systems based on their glazing temperatures; operating systems have lower glazing temperatures than those in stagnation. In recent years thousands of new solar hot water (SHW) systems have been installed in some utility districts. As these numbers increase, concern is growing about the systems dependability because installation rebates are often based on the assumption that all of the SHW systems will perform flawlessly for a 20-year period. If SHW systems routinely fail prematurely, then the utilities will have overpaid for grid-energy reduction performance that is unrealized. Moreover, utilities are responsible for replacing energy for loads that failed SHW system were supplying. Thus, utilities are seeking data to quantify the reliability of SHW systems. The work described herein is intended to help meet this need. The details of the experiment are presented, including a description of the SHW collectors that were examined, the testbed that was used to control the system and record data, the IR camera that was employed, and the conditions in which testing was completed. The details of the associated analysis are presented, including direct examination of the video records of operational and stagnant collectors, as well as the development of a model to predict glazing temperatures and an analysis of temporal intermittency of the images, both of which are critical to properly adjusting the IR camera for optimal performance. Many IR images and a video are presented to show the contrast between operating and stagnant collectors. The major conclusion is that the technique has potential to be applied by using an aircraft fitted with an IR camera that can fly over an area with installed SHW systems, thus recording the images. Subsequent analysis of the images can determine the operational condition of the fielded collectors. Specific

  7. Researching on Control Device of Prestressing Wire Reinforcement

    Science.gov (United States)

    Si, Jianhui; Guo, Yangbo; Liu, Maoshe

    2017-06-01

    This paper mainly introduces a device for controlling prestress and its related research methods, the advantage of this method is that the reinforcement process is easy to operate and control the prestress of wire rope accurately. The relationship between the stress and strain of the steel wire rope is monitored during the experiment, and the one - to - one relationship between the controllable position and the pretightening force of the steel wire rope is confirmed by the 5mm steel wire rope, and the results are analyzed theoretically by the measured elastic modulus. The results show that the method can effectively control the prestressing force, and the result provides a reference method for strengthening the concrete column with prestressed steel strand.

  8. Σχεδιασμός, ανάπτυξη και κατασκευή διάταξης ανεμομέτρου θερμαινόμενου σύρματος (Hot wire anemometry)

    OpenAIRE

    Κωνσταντίνου, Κωνσταντίνος

    2014-01-01

    Η παρούσα εργασία πραγματεύεται τη μελέτη και κατασκευή μιας μονάδας ανεμομέτρου θερμού σύρματος (Hot wire anemometer). Η εργασία αυτή εκπονήθηκε στο Εργαστήριο Θερμοκινητήρων του Τμήματος Μηχανολόγων και Αεροναυπηγών Μηχανικών της Πολυτεχνικής Σχολής του Πανεπιστημίου Πατρών. Σκοπός είναι η μελέτη, σχεδιασμός, κατασκευή και δοκιμή μιας μονοκάναλης μονάδας θερμού σύρματος σταθερής θερμοκρασίας (constant temperature anemometer CTA). Η μέθοδος του Hot wire anemometer χρησιμοποιείται για την...

  9. Synthesis of chemical vapor deposition graphene on tantalum wire for supercapacitor applications

    Energy Technology Data Exchange (ETDEWEB)

    Li, Mingji, E-mail: limingji@163.com [Tianjin Key Laboratory of Film Electronic and Communicate Devices, School of Electronics Information Engineering, Tianjin University of Technology, Tianjin 300384 (China); Guo, Wenlong [Tianjin Key Laboratory of Film Electronic and Communicate Devices, School of Electronics Information Engineering, Tianjin University of Technology, Tianjin 300384 (China); Li, Hongji, E-mail: hongjili@yeah.net [Tianjin Key Laboratory of Organic Solar Cells and Photochemical Conversion, School of Chemistry and Chemical Engineering, Tianjin University of Technology, Tianjin 300384 (China); Xu, Sheng [School of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072 (China); Qu, Changqing; Yang, Baohe [Tianjin Key Laboratory of Film Electronic and Communicate Devices, School of Electronics Information Engineering, Tianjin University of Technology, Tianjin 300384 (China)

    2014-10-30

    Highlights: • The capacitance of graphene/tantalum (Ta) wire electrodes is firstly reported. • Graphene was grown on the Ta surface by hot-filament chemical vapor deposition. • Graphene/Ta wire structure is favorable for fast ion and electron transfer. • The graphene/Ta wire electrode shows high capacitive properties. - Abstract: This paper studies the synthesis and electrochemical characterization of graphene/tantalum (Ta) wires as high-performance electrode material for supercapacitors. Graphene on Ta wires is prepared by the thermal decomposition of methane under various conditions. The graphene nanosheets on the Ta wire surface have an average thickness of 1.3–3.4 nm and consist typically of a few graphene monolayers, and TaC buffer layers form between the graphene and Ta wire. A capacitor structure is fabricated using graphene/Ta wire with a length of 10 mm and a diameter of 0.6 mm as the anode and Pt wire of the same size as the cathode. The electrochemical behavior of the graphene/Ta wires as supercapacitor electrodes is characterized by cyclic voltammetry, galvanostatic charge/discharge, and electrochemical impedance spectroscopy in 1 M Na{sub 2}SO{sub 4} aqueous electrolyte. The as-prepared graphene/Ta electrode has highest capacitance of 345.5 F g{sup −1} at current density of 0.5 A g{sup −1}. The capacitance remains at about 84% after 1000 cycles at 10 A g{sup −1}. The good electrochemical performance of the graphene/Ta wire electrode is attributed to the unique nanostructural configuration, high electrical conductivity, and large specific surface area of the graphene layer. This suggests that graphene/Ta wire electrode materials have potential applications in high-performance energy storage devices.

  10. Sample of superconducting wiring from the LHC

    CERN Document Server

    The high magnetic fields needed for guiding particles around the Large Hadron Collider (LHC) ring are created by passing 12’500 amps of current through coils of superconducting wiring. At very low temperatures, superconductors have no electrical resistance and therefore no power loss. The LHC is the largest superconducting installation ever built. The magnetic field must also be extremely uniform. This means the current flowing in the coils has to be very precisely controlled. Indeed, nowhere before has such precision been achieved at such high currents. Magnet coils are made of copper-clad niobium–titanium cables — each wire in the cable consists of 9’000 niobium–titanium filaments ten times finer than a hair. The cables carry up to 12’500 amps and must withstand enormous electromagnetic forces. At full field, the force on one metre of magnet is comparable to the weight of a jumbo jet. Coil winding requires great care to prevent movements as the field changes. Friction can create hot spots wh...

  11. Non-LTE line-blanketed model atmospheres of hot stars. 1: Hybrid complete linearization/accelerated lambda iteration method

    Science.gov (United States)

    Hubeny, I.; Lanz, T.

    1995-01-01

    A new munerical method for computing non-Local Thermodynamic Equilibrium (non-LTE) model stellar atmospheres is presented. The method, called the hybird complete linearization/accelerated lambda iretation (CL/ALI) method, combines advantages of both its constituents. Its rate of convergence is virtually as high as for the standard CL method, while the computer time per iteration is almost as low as for the standard ALI method. The method is formulated as the standard complete lineariation, the only difference being that the radiation intensity at selected frequency points is not explicity linearized; instead, it is treated by means of the ALI approach. The scheme offers a wide spectrum of options, ranging from the full CL to the full ALI method. We deonstrate that the method works optimally if the majority of frequency points are treated in the ALI mode, while the radiation intensity at a few (typically two to 30) frequency points is explicity linearized. We show how this method can be applied to calculate metal line-blanketed non-LTE model atmospheres, by using the idea of 'superlevels' and 'superlines' introduced originally by Anderson (1989). We calculate several illustrative models taking into accont several tens of thosands of lines of Fe III to Fe IV and show that the hybrid CL/ALI method provides a robust method for calculating non-LTE line-blanketed model atmospheres for a wide range of stellar parameters. The results for individual stellar types will be presented in subsequent papers in this series.

  12. Modification of the BAX Salmonella test kit to include a hot start functionality (modification of AOAC Official Method 2003.09).

    Science.gov (United States)

    Wallace, F Morgan; DiCosimo, Deana; Farnum, Andrew; Tice, George; Andaloro, Bridget; Davis, Eugene; Burns, Frank R

    2011-01-01

    In 2010, the BAX System PCR assay for Salmonella was modified to include a hot start functionality designed to keep the reaction enzyme inactive until PCR begins. To validate the assay's Official Methods of Analysis status to include this procedure modification, an evaluation was conducted on four food types that were simultaneously analyzed with the BAX System and either the U.S. Food and Drug Administration's Bacteriological Analytical Manual or the U.S. Department of Agriculture-Food Safety and Inspection Service Microbiology Laboratory Guidebook reference method for detecting Salmonella. Identical performance between the BAX System method and the reference methods was observed. Additionally, lysates were analyzed using both the BAX System Classic and BAX System Q7 instruments with identical results using both platforms for all samples tested. Of the 100 samples analyzed, 34 samples were positive for both the BAX System and reference methods, and 66 samples were negative by both the BAX System and reference methods, demonstrating 100% correlation. No instrument platform variation was observed. Additional inclusivity and exclusivity testing using the modified test kit demonstrated the test kit to be 100% accurate in evaluation of test panels of 352 Salmonella strains and 46 non-Salmonella strains.

  13. Most Wired 2006: measuring value.

    Science.gov (United States)

    Solovy, Alden

    2006-07-01

    As the Most Wired hospitals incorporate information technology into their strategic plans, they combine a"balanced scorecard"approach with classic business analytics to measure how well IT delivers on their goals. To find out which organizations made this year's 100 Most Wired list, as well as those named in other survey categories, go to the foldout section.

  14. A review on hot tearing of magnesium alloys

    Directory of Open Access Journals (Sweden)

    Jiangfeng Song

    2016-09-01

    Full Text Available Hot tearing is often a major casting defect in magnesium alloys and has a significant impact on the quality of their casting products. Hot tearing of magnesium alloys is a complex solidification phenomenon which is still not fully understood, it is of great importance to investigate the hot tearing behaviour of magnesium alloys. This review attempts to summarize the investigations on hot tearing of magnesium alloys over the past decades. The hot tearing criteria including recently developed Kou's criterion are summarized and compared. The numeric simulation and assessing methods of hot tearing, factors influencing hot tearing, and hot tearing susceptibility (HTS of magnesium alloys are discussed.

  15. An improved method of high-precision determination of Δ(17)O of CO2 by catalyzed exchange with O2 using hot platinum.

    Science.gov (United States)

    Mahata, Sasadhar; Bhattacharya, S K; Liang, Mao-Chang

    2016-01-15

    CO2 and O2 can exchange their oxygen isotopes rapidly in the presence of hot (~670 °C) platinum and this has led to a method for determining the δ(17)O value of a CO2 sample. We have improved the method to achieve a precision of 0.008 ‰ (1-σ standard deviation) in the determination of δ(17)O values. Such high precision is essential to identify the stratospheric component in tropospheric CO2 and use it for global carbon flux studies. The crucial issue in the accurate determination of the δ(17)O value is estimation of a correction factor, which depends on the amount ratio CO2/O2. An attempt was also made to investigate the mechanism of exchange with their controlling parameters. The oxygen isotopes of a CO2 sample gas are exchanged with those of an appropriate amount of tank O2 in the presence of hot platinum. The pre-exchange CO2 and O2 gas samples as well as the post-exchange O2 sample are analyzed by isotope ratio mass spectrometry. A mixing model was developed involving the δ(18)O value of the CO2 and δ(17)O and δ(18)O values of pre- and post-exchange O2 to obtain the δ(17)O value of the CO2 sample. A correction to the measured value was determined to obtain the actual value with high accuracy and precision. To obtain a precision better than 0.01 ‰ requires the amount ratio CO2/O2 to be controlled to better than ~15 %. We also find that the oxygen isotopes are nearly homogeneously distributed between the O2 and the CO2 molecules. In addition, determination of the (16) O(13)C(18)O/(16)O(12)C(16)O isotopologue ratio in the CO2 shows that the abundance of (16)O(13)C(18)O is close to that expected for random partitioning of the isotopes among the CO2 isotopologues. The isotopic scrambling between O2 and CO2 that occurs on hot platinum allows one to accurately determine the δ(17)O values of CO2 through isotopic analysis of O2. Copyright © 2015 John Wiley & Sons, Ltd.

  16. Prediction of grain deformation in drawn copper wire

    Directory of Open Access Journals (Sweden)

    Chang Chao-Cheng

    2015-01-01

    Full Text Available Most copper wire is produced using a drawing process. The crystallographic texture of copper wire, which is strongly associated with grain deformation, can have a profound effect on the formability and mechanical and electrical properties. Thus, the ability to predict grain deformation in drawn copper wire could help to elucidate the evolution of microstructure, which could be highly valuable in product design. This study developed a novel method for predicting grain deformation in drawn copper wire based on finite element simulation with flow net analysis. Simple upsetting tests were conducted to obtain flow stress curves for the simulation of the drawing process. Predictions related to grain deformation were compared with those on the micrographs of the drawn copper wire obtained in experiments. In longitudinal and transverse cross-sections of the drawn wire, the predicted and experiment results presented similar trends involving considerable deformation within the grains. This preliminary study demonstrates the efficacy of the proposed method in providing information useful to the prediction of the grain deformation in drawn copper wire.

  17. Synthesis of Highly Bright Oil-Soluble Carbon Quantum Dots by Hot-Injection Method with N and B Co-Doping.

    Science.gov (United States)

    Tan, Longfei; Huang, Guanbao; Liu, Tianlong; Fu, Changhui; Zhou, Yuan; Zhu, Zhiguo; Meng, Xianwei

    2016-03-01

    Oil-soluble BN-doped carbon quantum dots (CQDs) were successfully prepared in a novel hot-injection method by using 1,2-Hexadecanediol as carbon precursor and surface passivation agent. The reaction time, temperature, and surface passivation agent were investigated by fluorescence measurements to understand the underlying evolution of CQDs. The doping of N and B were carried out by choosing suitable N and B source, evaluated by their fluorescence properties. The size, morphology and surface properties were observed by TEM, AFM and FTIR measurements. The quantum yields of CQDs were also calculated to investigate the enhanced fluorescence properties. The prepared oil-soluble BN-doped CQDs were easily dispersed into organic solvent, showing great potential to produce optical and sensing devices.

  18. Formulation and Implementation of Energy Efficient Ultraviolet Curing for Photosensitive Resin-Bound Diamond Wire Saws

    Directory of Open Access Journals (Sweden)

    Chunyan Yao

    2013-01-01

    Full Text Available It is a currently dominant method to use wire saws for cutting silicon material because of its production efficiency and energy efficiency. Diamond wire saws, or fixed abrasive wire saws, have attracted much attention to researchers and engineers due to many advantages, including high cutting efficiency and low environmental pollution. This paper develops a novel diamond wire saw using ultraviolet curing technology. High-strength piano wires and polyethylene wires are selected as wire cores, and photosensitive resin is used as the binder. The problem of wire saw strength is mathematically formulated, and the effective parameters are analyzed. The surface morphology is analyzed for the developed diamond wire saw. A series of cutting experiments with different saws of varying manufacturing parameters are carried out. The slicing performance of such diamond wire saws is evaluated and compared. The experimental results show that the developed saw using the photosensitive resin has a very good performance in slicing silicon ingots. By the comparison between the developed diamond wire saw and the electroplated diamond wire saw, the surface smoothness of the workpiece is better than that by the latter.

  19. Determining the refractive index dispersion and thickness of hot-pressed chalcogenide thin films from an improved Swanepoel method

    DEFF Research Database (Denmark)

    Fang, Y. Z.; Jayasuriya, D.; Furniss, David

    2017-01-01

    The well-known method presented by Swanepoel can be used to determine the refractive index dispersion of thin films in the near-infrared region from wavelength values at maxima and minima, only, of the transmission interference fringes. In order to extend this method into the mid-infrared spectral...

  20. [Separate vertical wiring combined with tension band and Kirschner-wire plus cerclage wire in the treatment of displaced inferior pole fractures of the patella].

    Science.gov (United States)

    Zhang, J; Jiang, X Y; Huang, X W

    2016-06-18

    To investigate the clinical efficacy and outcomes of two separate vertical wiring combined with tension band and Kirschner-wire plus cerclage wire in the treatment of displaced inferior pole fractures of the patella. From January 2013 to January 2015, 15 consecutive patients (mean age 54.5 years) with inferior pole fractures of the patella were retrospectively included in this study. All the patients underwent open reduction and internal fixation by separate vertical wiring combined with tension band and Kirschner-wire plus cerclage wire through longitudinal incision, 4.5 d (range: 3.1-5.9 d) after initial injury. A safety check for early knee range of motion was performed before wound closure. The complications including infection, nonunion, loss of fixation and any wire breakage or irritation from implant were recorded. Anteroposterior and lateral views of the knee joint obtained during the follow-up were used to assess bony union based on the time when the fracture line disappeared. At the time of the final outpatient follow up, functional evaluation of the knee joint was conducted by Bostman system. The follow-up time was 13.1 months (range: 12-19 months) after surgery on average, immediate motion without immobilization in all the cases was allowed and there was no case of reduction loss of the fracture and wire breakage. There was no case of irritation from the implant. At the final follow-up, the average range of motion (ROM) arc was 126.7° (range: 115°-140°), the average ROM lag versus contralateral healthy leg was 10.3° (range: 0°-35°). The mean Bostman score at the last follow-up was 28.9 (range: 27-30), and graded excellent in most cases. Two separate vertical wiring is an easy and effective method to reduce the displaced inferior pole fracture of patella. Augmentation of separate vertical wiring with tension band and Kirschner-wire plus cerclage wire in these patients provides enough strength to protected the early exercise of the knee joint and

  1. Métodos transientes de troca de calor na determinação das propriedades térmicas de materiais cerâmicos: II - o método do fio quente Thermal properties of ceramic materials by the non-steady techniques: II - the hot wire technique

    Directory of Open Access Journals (Sweden)

    W. N. dos Santos

    2005-12-01

    diffusivity is important in non-steady heat transfer calculations. The specific heat is also a decisive property of ceramic materials in high temperature applications, and it is associated with heat consumption during the heating process. Normally these properties are determined separately by individual techniques and apparatus. Nowadays, several different techniques for the determination of the thermal diffusivity and thermal conductivity may be found in the literature. Recently, transient techniques have become the preferable way for measuring thermal properties of materials. In this work it is presented a description as well as a critical analysis of one experimental technique employed worldwide for thermal properties measurements of ceramic materials: the hot wire technique. With this technique it is possible to determine simultaneously from the same temperature transient the three thermal properties. Numerical results are also presented.

  2. Antibacterial Modification of Kirschner Wires with Polyluteolin toward Methicillin-Resistant Staphylococcus aureus (MRSA

    Directory of Open Access Journals (Sweden)

    Jialiang Zhu

    2015-07-01

    Full Text Available In this study we report antibacterial modification of Kirschner wires (K-wires with polyluteolin (PL toward methicillin-resistant Staphylococcus aureus (MRSA. K-wires were modified by immersing them in the luteolin-containing aqueous solution for 24 h. Characterizations using scanning electron microscopy and electrochemical methods confirmed the presence of the PL coatings on the K-wires. The PL-coated K-wires were further found to show antibacterial activity toward MRSA and remained unimpaired antibacterial activity even after the steam sterilization treatment.

  3. Spectrum of localized states in graphene quantum dots and wires

    Energy Technology Data Exchange (ETDEWEB)

    Zalipaev, V.V. [Department of Mathematical Sciences, Loughborough University, Leicestershire, LE11 3TU (United Kingdom); Maksimov, D.N. [LV Kirensky Institute of Physics, Krasnoyarsk 660036 (Russian Federation); Linton, C.M. [Department of Mathematical Sciences, Loughborough University, Leicestershire, LE11 3TU (United Kingdom); Kusmartsev, F.V., E-mail: F.Kusmartsev@lboro.ac.uk [Department of Physics, Loughborough University, Leicestershire, LE11 3TU (United Kingdom)

    2013-01-03

    We developed semiclassical method and show that any smooth potential in graphene describing elongated a quantum dot or wire may behave as a barrier or as a trapping well or as a double barrier potential, Fabry–Perot structure, for 1D Schrödinger equation. The energy spectrum of quantum wires has been found and compared with numerical simulations. We found that there are two types of localized states, stable and metastable, having finite life time. These life times are calculated, as is the form of the localized wave functions which are exponentially decaying away from the wire in the perpendicular direction.

  4. Measurement of Capsaicinoids in Chiltepin Hot Pepper: A Comparison Study between Spectrophotometric Method and High Performance Liquid Chromatography Analysis

    OpenAIRE

    Alberto González-Zamora; Erick Sierra-Campos; Rebeca Pérez-Morales; Cirilo Vázquez-Vázquez; Miguel A. Gallegos-Robles; López-Martínez, José D.; García-Hernández, José L.

    2015-01-01

    Direct spectrophotometric determination of capsaicinoids content in Chiltepin pepper was investigated as a possible alternative to HPLC analysis. Capsaicinoids were extracted from Chiltepin in red ripe and green fruit with acetonitrile and evaluated quantitatively using the HPLC method with capsaicin and dihydrocapsaicin standards. Three samples of different treatment were analyzed for their capsaicinoids content successfully by these methods. HPLC-DAD revealed that capsaicin, dihydrocapsaici...

  5. Thermal-Hydraulic Effect of Pattern of Wire-wrap Spacer in 19-pin Rod Bundle for SFR Fuel Assembly

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Yeong Shin; Bang, In Cheol [UNIST, Ulsan (Korea, Republic of); Park, Seong Dae [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    As sodium-cooled fast reactor (SFR) has been considered the most promising reactor type for future and prototype gen-IV SFR has been developed actively in Korea, thermal-hydraulic aspects of the SFR fuel assembly have the important role for the reactor safety analysis. In PGSFR fuel assembly, 271 pins of fuel rods are tightly packed in triangular array inside hexagonal duct, and wire is wound helically per each fuel rod with regular pattern to assure the gap between rods and prevent the collision, which is called wire-wrapped spacer. Due to helical shape of the wire-wrapped spacer, flow inside duct can have stronger turbulent characteristics and thermal mixing effect. However, many studies showed the possible wake from swirl flow inside subchannel, which cause local hot spot. To prevent the wake flow and improve thermal mixing, new pattern of wire wrap spacer was suggested. To evaluate the effect of wire wrap spacer pattern, CFD analysis was performed for 19-pin rod bundle with comparison of conventional and U-pattern wire wrap spacer. To prevent the wake due to same direction of swirl flow, 7-rod unit pattern of wire spacer, which are arranged to have different rotational direction of wire with adjacent rods and center rod without wire wrap was proposed. From simulation results, swirl flow across gap conflicts its rotation direction causing wake flow from the regular pattern of the conventional one, which generates local hot spot near cladding. With U-pattern of wire wrap spacer, heat transfer in subchannel can be enhanced with evenly distributed cross flow without compensating pressure loss. From the results, the pattern of wire wrap spacer can influence the both heat transfer characteristics and pressure drop, with flow structures generated by wire wrap spacer.

  6. Capacitance Control on the Wire Production Line

    Directory of Open Access Journals (Sweden)

    Goldshtein Alexander

    2016-01-01

    Full Text Available The paper presents technical implementation of the electricalcapacitive method to perform in-process measurement of the capacitance per unit length of a single-core electric wire. The design of the electrocapacitive measuring transducer is proposed. The block diagram of the device CAP-10 developed to implement the proposed method is presented. The appearance of the device CAP-10 is showed, and its operating principle is described. It is shown that the change in water conductivity has a significant impact of the measurement result of the wire capacitance per unit length. The techniques to offset from the impact of water conductivity variation on measurement results are proposed. The technique of the device CAP-10 initial adjustment is proposed. It provides the desired function of the output signal transformation. The technique of the ‘operating’ adjustment to correct measurement results through systematic measurement error elimination is offered.

  7. Measurement of Capsaicinoids in Chiltepin Hot Pepper: A Comparison Study between Spectrophotometric Method and High Performance Liquid Chromatography Analysis

    Directory of Open Access Journals (Sweden)

    Alberto González-Zamora

    2015-01-01

    Full Text Available Direct spectrophotometric determination of capsaicinoids content in Chiltepin pepper was investigated as a possible alternative to HPLC analysis. Capsaicinoids were extracted from Chiltepin in red ripe and green fruit with acetonitrile and evaluated quantitatively using the HPLC method with capsaicin and dihydrocapsaicin standards. Three samples of different treatment were analyzed for their capsaicinoids content successfully by these methods. HPLC-DAD revealed that capsaicin, dihydrocapsaicin, and nordihydrocapsaicin comprised up to 98% of total capsaicinoids detected. The absorbance of the diluted samples was read on a spectrophotometer at 215–300 nm and monitored at 280 nm. We report herein the comparison between traditional UV assays and HPLC-DAD methods for the determination of the molar absorptivity coefficient of capsaicin (ε280=3,410 and ε280=3,720 M−1 cm−1 and dihydrocapsaicin (ε280=4,175 and ε280=4,350 M−1 cm−1, respectively. Statistical comparisons were performed using the regression analyses (ordinary linear regression and Deming regression and Bland-Altman analysis. Comparative data for pungency was determined spectrophotometrically and by HPLC on samples ranging from 29.55 to 129 mg/g with a correlation of 0.91. These results indicate that the two methods significantly agree. The described spectrophotometric method can be routinely used for total capsaicinoids analysis and quality control in agricultural and pharmaceutical analysis.

  8. Plasma chemistry in wire chambers

    Energy Technology Data Exchange (ETDEWEB)

    Wise, J.

    1990-05-01

    The phenomenology of wire chamber aging is discussed and fundamentals of proportional counters are presented. Free-radical polymerization and plasma polymerization are discussed. The chemistry of wire aging is reviewed. Similarities between wire chamber plasma (>1 atm dc-discharge) and low-pressure rf-discharge plasmas, which have been more widely studied, are suggested. Construction and use of a system to allow study of the plasma reactions occurring in wire chambers is reported. A proportional tube irradiated by an {sup 55}Fe source is used as a model wire chamber. Condensable species in the proportional tube effluent are concentrated in a cryotrap and analyzed by gas chromatography/mass spectrometry. Several different wire chamber gases (methane, argon/methane, ethane, argon/ethane, propane, argon/isobutane) are tested and their reaction products qualitatively identified. For all gases tested except those containing methane, use of hygroscopic filters to remove trace water and oxygen contaminants from the gas resulted in an increase in the average molecular weight of the products, consistent with results from low-pressure rf-discharge plasmas. It is suggested that because water and oxygen inhibit polymer growth in the gas phase that they may also reduce polymer deposition in proportional tubes and therefore retard wire aging processes. Mechanistic implications of the plasma reactions of hydrocarbons with oxygen are suggested. Unresolved issues in this work and proposals for further study are discussed.

  9. Buoyant Helical Twin-Axial Wire Antenna

    Science.gov (United States)

    2016-11-15

    Wire Antenna” by the inventor, David A. Tonn. STATEMENT OF GOVERNMENT INTEREST [0002] The invention described herein may be manufactured and used by...BACKGROUND OF THE INVENTION (1) Field of the Invention [0003] The present invention is directed to a linear antenna for dual frequencies and a method for...curves and hinders the submarine’s operations when using the antenna. SUMMARY OF THE INVENTION [0006] It is a first object of the present

  10. Computer simulation of metal wire explosion under high rate heating

    Science.gov (United States)

    Zolnikov, K. P.; Kryzhevich, D. S.; Korchuganov, A. V.

    2017-05-01

    Synchronous electric explosion of metal wires and synthesis of bicomponent nanoparticles were investigated on the base of molecular dynamics method. Copper and nickel nanosized crystallites of cylindrical shape were chosen as conductors for explosion. The embedded atom approximation was used for calculation of the interatomic interactions. The agglomeration process after explosion metal wires was the main mechanism for particle synthesis. The distribution of chemical elements was non-uniform over the cross section of the bicomponent particles. The copper concentration in the surface region was higher than in the bulk of the synthesized particle. By varying the loading parameters (heating temperature, the distance between the wires) one can control the size and internal structure of the synthesized bicomponent nanoparticles. The obtained results showed that the method of molecular dynamics can be effectively used to determine the optimal technological mode of nanoparticle synthesis on the base of electric explosion of metal wires.

  11. Resilient response characterisation of hot-mix asphalt mixes for a new South African pavement design method

    CSIR Research Space (South Africa)

    Anochie-Boateng, Joseph

    2011-09-01

    Full Text Available The South Africa National Road Agency Ltd (SANRAL) is in the process of revising the South African Pavement Design Method (SAPDM). A necessary part of this programme is to develop resilient response models. Dynamic (complex) modulus has been used...

  12. ‘Chrysanthemum petal’ arrangements of silver nano wires

    Science.gov (United States)

    Cui, Hui-Wang; Jiu, Jin-Ting; Sugahara, Tohru; Nagao, Shijo; Suganuma, Katsuaki; Uchida, Hiroshi

    2014-12-01

    Highly ordered ‘Chrysanthemum petal’ arrangements of silver nano wires were fabricated in a biodegradable polymer of polyvinyl alcohol using a simple one-step blending method without any template. The degree of the arrangement increased with the decreasing content of polyvinyl alcohol. The mechanism for the formation of these ‘Chrysanthemum petal’ arrangements was discussed specifically. These ‘Chrysanthemum petal’ arrangements will be helpful to increase the electrical conductivity of silver nano wires films.

  13. Hot-filament metal oxide deposition (HFMOD: a novel method for depositing thin films of metallic oxides

    Directory of Open Access Journals (Sweden)

    Rouxinol F. Paulo

    2004-01-01

    Full Text Available This short report describes a novel method for the synthesis of metal oxide thin films. The experimental setup consists of a metal filament installed inside a vacuum chamber. The filament can be heated by an ac power supply while oxygen is admitted into the chamber using a mass flowmeter. From reactions between oxygen and the heated metal filament, volatile oxide species, Me xOy, where Me is the metal, can be formed, condensing on a nearby substrate. We have observed that thin films of WxOy and Mo xOy can be satisfactorily deposited by this novel method. Although several techniques were used to characterize the oxides, this note emphasizes the results obtained by X-ray Photoelectron Spectroscopy (XPS.

  14. 7 CFR 1755.860 - RUS specification for filled buried wires.

    Science.gov (United States)

    2010-01-01

    ... conductors which are used within the RUS program are provided in the following table: American Wire Gauge... American National Standards Institute/Electronic Industries Association (ANSI/EIA) 359-A-84, EIA Standard... Materials specifications (ASTM) A 505-87, Standard Specification for Steel, Sheet and Strip, Alloy, Hot...

  15. Use of beam deflection to control an electron beam wire deposition process

    Science.gov (United States)

    Taminger, Karen M. (Inventor); Hofmeister, William H. (Inventor); Hafley, Robert A. (Inventor)

    2013-01-01

    A method for controlling an electron beam process wherein a wire is melted and deposited on a substrate as a molten pool comprises generating the electron beam with a complex raster pattern, and directing the beam onto an outer surface of the wire to thereby control a location of the wire with respect to the molten pool. Directing the beam selectively heats the outer surface of the wire and maintains the position of the wire with respect to the molten pool. An apparatus for controlling an electron beam process includes a beam gun adapted for generating the electron beam, and a controller adapted for providing the electron beam with a complex raster pattern and for directing the electron beam onto an outer surface of the wire to control a location of the wire with respect to the molten pool.

  16. Cavity Mode Related Wire Breaking of the SPS Wire Scanners and Loss Measurements of Wire Materials

    CERN Document Server

    Caspers, Friedhelm; Jensen, E; Koopman, J; Malo, J F; Roncarolo, F

    2003-01-01

    During the SPS high intensity run 2002 with LHC type beam, the breaking of several of the carbon wires in the wire scanners has been observed in their parking position. The observation of large changes in the wire resistivity and thermionic electron emission clearly indicated strong RF heating that was depending on the bunch length. A subsequent analysis in the laboratory, simulating the beam by two probe antennas or by a powered stretched wire, showed two main problems: i) the housing of the wire scanner acts as a cavity with a mode spectrum starting around 350 MHz and high impedance values around 700 MHz; ii) the carbon wire used so far appears to be an excellent RF absorber and thus dissipates a significant part of the beam-induced power. Different wire materials are compared with the classical cavity mode technique for the determination of the complex permittivity in the range of 2-4 GHz. As a resonator a rectangular TE_01n type device is utilized.

  17. Cavity mode related wire breaking of the SPS Wire Scanners and loss measurements of wire materials

    CERN Document Server

    Roncarolo, Federico

    2003-01-01

    During the SPS high intensity run 2002 with LHC type beam, the breaking of several of the carbon wires in the wire scanners has been observed in their parking position. The observation of large changes in the wire resistivity and thermionic electron emission clearly indicated strong RF heating that was depending on the bunch length. A subsequent analysis in the laboratory, simulating the beam by two probe antennas or by a powered stretched wire, showed two main problems: i) the housing of the wire scanner acts as a cavity with a mode spectrum starting around 350MHz and high impedance values around 700 MHz; ii) the carbon wire used so far appears to be an excellent RF absorber and thus dissipates a significant part of the beam-induced power. Different wire materials are compared with the classical cavity mode technique for the determination of the complex permittivity in the range of 2-4 GHz. As a resonator a rectangular TE01n type device is utilized.

  18. Modeling birds on wires.

    Science.gov (United States)

    Aydoğdu, A; Frasca, P; D'Apice, C; Manzo, R; Thornton, J M; Gachomo, B; Wilson, T; Cheung, B; Tariq, U; Saidel, W; Piccoli, B

    2017-02-21

    In this paper we introduce a mathematical model to study the group dynamics of birds resting on wires. The model is agent-based and postulates attraction-repulsion forces between the interacting birds: the interactions are "topological", in the sense that they involve a given number of neighbors irrespective of their distance. The model is first mathematically analyzed and then simulated to study its main properties: we observe that the model predicts birds to be more widely spaced near the borders of each group. We compare the results from the model with experimental data, derived from the analysis of pictures of pigeons and starlings taken in New Jersey: two different image elaboration protocols allow us to establish a good agreement with the model and to quantify its main parameters. We also discuss the potential handedness of the birds, by analyzing the group organization features and the group dynamics at the arrival of new birds. Finally, we propose a more refined mathematical model that describes landing and departing birds by suitable stochastic processes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Topology Optimized Photonic Wire Splitters

    DEFF Research Database (Denmark)

    Frandsen, Lars Hagedorn; Borel, Peter Ingo; Jensen, Jakob Søndergaard

    2006-01-01

    Photonic wire splitters have been designed using topology optimization. The splitters have been fabricated in silicon-on-insulator material and display broadband low-loss 3dB splitting in a bandwidth larger than 100 nm.......Photonic wire splitters have been designed using topology optimization. The splitters have been fabricated in silicon-on-insulator material and display broadband low-loss 3dB splitting in a bandwidth larger than 100 nm....

  20. Spatial characterization of hot melt extruded dispersion systems using thermal atomic force microscopy methods: the effects of processing parameters on phase separation.

    Science.gov (United States)

    Moffat, Jonathan G; Qi, Sheng; Craig, Duncan Q M

    2014-07-01

    In this study we explore the use of nano-scale localized thermal analysis (LTA) and transition temperature microcopy (TTM) as a novel combined approach to studying phase separation in HME dispersions of cyclosporine A in Eudragit EPO. Modulated temperature differential scanning calorimetry (MTDSC), attenuated total reflectance FTIR spectroscopy, nano-LTA and TTM were performed on raw materials and dispersions prepared by hot melt extrusion (HME) and spin coating. For samples prepared by HME, two mixing temperatures (110°C and 150°C) and residence times (5 and 15 min) were investigated. Spin coated samples showed an intermediate T g for the mixed systems consistent with molecular dispersion formation. The HME samples prepared at 110°C showed evidence of inhomogeneity using MTDSC and FTIR, while those produced at 150°C h showed evidence for the formation of a single phase system using MTDSC. The nanothermal methods, however, indicated the presence of phase separated cyclosporine A at the higher preparation temperature while the TTM was able to map regions of differing penetration temperatures, indicating the presence of compositionally inhomogeneous regions in all but the high processing temperature/high residence time samples. TTM is a potentially important new method for studying phase separation and that such separation may remain undetected or poorly understood using conventional bulk analytical techniques.

  1. HTS Wire Development Workshop: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    1994-07-01

    The 1994 High-Temperature Superconducting Wire Development Workshop was held on February 16--17 at the St. Petersburg Hilton and Towers in St. Petersburg, Florida. The meeting was hosted by Florida Power Corporation and sponsored by the US Department of Energy`s Superconductivity Program for Electric Power Systems. The meeting focused on recent high-temperature superconducting wire development activities in the Department of Energy`s Superconductivity Systems program. The meeting opened with a general discussion on the needs and benefits of superconductivity from a utility perspective, the US global competitiveness position, and an outlook on the overall prospects of wire development. The meeting then focused on four important technology areas: Wire characterization: issues and needs; technology for overcoming barriers: weak links and flux pinning; manufacturing issues for long wire lengths; and physical properties of HTS coils. Following in-depth presentations, working groups were formed in each technology area to discuss the most important current research and development issues. The working groups identified research areas that have the potential for greatly enhancing the wire development effort. These areas are discussed in the summary reports from each of the working groups. This document is a compilation of the workshop proceedings including all general session presentations and summary reports from the working groups.

  2. Wire Array Solar Cells: Fabrication and Photoelectrochemical Studies

    Science.gov (United States)

    Spurgeon, Joshua Michael

    Despite demand for clean energy to reduce our addiction to fossil fuels, the price of these technologies relative to oil and coal has prevented their widespread implementation. Solar energy has enormous potential as a carbon-free resource but is several times the cost of coal-produced electricity, largely because photovoltaics of practical efficiency require high-quality, pure semiconductor materials. To produce current in a planar junction solar cell, an electron or hole generated deep within the material must travel all the way to the junction without recombining. Radial junction, wire array solar cells, however, have the potential to decouple the directions of light absorption and charge-carrier collection so that a semiconductor with a minority-carrier diffusion length shorter than its absorption depth (i.e., a lower quality, potentially cheaper material) can effectively produce current. The axial dimension of the wires is long enough for sufficient optical absorption while the charge-carriers are collected along the shorter radial dimension in a massively parallel array. This thesis explores the wire array solar cell design by developing potentially low-cost fabrication methods and investigating the energy-conversion properties of the arrays in photoelectrochemical cells. The concept was initially investigated with Cd(Se, Te) rod arrays; however, Si was the primary focus of wire array research because its semiconductor properties make low-quality Si an ideal candidate for improvement in a radial geometry. Fabrication routes for Si wire arrays were explored, including the vapor-liquid-solid growth of wires using SiCl4. Uniform, vertically aligned Si wires were demonstrated in a process that permits control of the wire radius, length, and spacing. A technique was developed to transfer these wire arrays into a low-cost, flexible polymer film, and grow multiple subsequent arrays using a single Si(111) substrate. Photoelectrochemical measurements on Si wire array

  3. 30 CFR 75.701-4 - Grounding wires; capacity of wires.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Grounding wires; capacity of wires. 75.701-4... SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Grounding § 75.701-4 Grounding wires; capacity of wires. Where grounding wires are used to ground metallic sheaths, armors, conduits, frames...

  4. 1 mil gold bond wire study.

    Energy Technology Data Exchange (ETDEWEB)

    Huff, Johnathon; McLean, Michael B.; Jenkins, Mark W.; Rutherford, Brian Milne

    2013-05-01

    In microcircuit fabrication, the diameter and length of a bond wire have been shown to both affect the current versus fusing time ratio of a bond wire as well as the gap length of the fused wire. This study investigated the impact of current level on the time-to-open and gap length of 1 mil by 60 mil gold bond wires. During the experiments, constant current was provided for a control set of bond wires for 250ms, 410ms and until the wire fused; non-destructively pull-tested wires for 250ms; and notched wires. The key findings were that as the current increases, the gap length increases and 73% of the bond wires will fuse at 1.8A, and 100% of the wires fuse at 1.9A within 60ms. Due to the limited scope of experiments and limited data analyzed, further investigation is encouraged to confirm these observations.

  5. ONLINE TECHNOLOGICAL MONITORING OF INSULATION DEFECTS IN ENAMELED WIRES

    Directory of Open Access Journals (Sweden)

    V. M. Zolotaryov

    2017-08-01

    Full Text Available In this paper the authors used non-destructive technological monitoring of defects insulation enameled wire with poliimid polymer. The paper is devoted to the statistical method for processing, comparison and analysis of results of measurements of parameters of insulation of enameled wire because of mathematical model of trend for application in active technological monitoring is developed; the recommendations for parameters of such monitoring are used. It is theoretically justified and the possibility of determination of dependence of the error on the velocity of movement of a wire for want of quantifying of defects in enameled insulation by non-destructive tests by high voltage. The dependence of average value of amount of defects for enameled wire with two-sheeted poliimid insulation in a range of nominal diameter 0.56 mm is experimentally determined. The technological monitoring purpose is to reduce the quantifying defects of enameled insulation.

  6. Corrosion resistance of premodeled wires made of stainless steel used for heart electrotherapy leaders

    Science.gov (United States)

    Przondziono, J.; Walke, W.; Młynarski, R.; Szatka, W.

    2012-05-01

    The purpose of the study is to evaluate resistance to electrochemical corrosion of wire made of X10CrNi18-8 stainless steel designed for use in cardiology treatment. The influence of strain formed in the premodeling process and methods of wire surface preparation to corrosive resistance in artificial plasma solution were analysed. Wire corrosion tests were carried out in the solution of artificial plasma. Resistance to electrochemical corrosion was evaluated on the ground of recorded curves of anodic polarization by means of potentiodynamic method. Potentiodynamic tests carried out enabled to determine how the resistance to pitting corrosion of wire changes, depending on strain formed in the premodeling process as well as on the method of wire surface preparation. For evaluation of phenomena occurring on the surface of tested steel, electrochemical impedance spectroscopy (EIS) was applied. Deterioration of corrosive properties of wire along with the increase in the formed strain hardening was observed.

  7. Study of micro-pinches in wire-array Z pinches

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, V. V.; Papp, D.; Anderson, A. A.; Talbot, B. R.; Astanovitskiy, A. L.; Nalajala, V.; Dmitriev, O. [Department of Physics, University of Nevada, Reno, Nevada 89557 (United States); Chittenden, J. P.; Niasse, N. [Blackett Laboratory, Imperial College, London SW7 2BZ (United Kingdom); Pikuz, S. A.; Shelkovenko, T. A. [P.N. Lebedev Physical Institute, Moscow 119991 (Russian Federation)

    2013-11-15

    Bright and hot areas with a high plasma density and temperature are observed in all kinds of Z pinches. We studied bright radiating spots produced by micro-pinches in cylindrical and planar wire-arrays at the 1 MA Zebra pulsed power generator using an x-ray streak camera synchronized with laser diagnostics, x-ray time-gated pinhole camera, and spectroscopy. Hot spots with extremely dense and relatively hot plasma arise during the collapse of the micro-pinches. These hot spots radiate a continuum spectrum with energy >2.5 keV. Typical micro-pinches in Al wire arrays generate x-ray bursts with durations of 0.4–1 ns in the soft x-ray range and 0.1–0.4 ns in the keV range. UV two-frame shadowgraphy shows spatial correlation of hot spots with the collapse and explosion of micro-pinches. Micro-pinches typically occur at the necks of the Z pinch, but can demonstrate a variety of parameters and different dynamics. An analysis of x-ray streak images shows that micro-pinches can generate >20% of the x-ray energy in some types of wire-array Z pinches.

  8. Humidity effects on wire insulation breakdown strength.

    Energy Technology Data Exchange (ETDEWEB)

    Appelhans, Leah

    2013-08-01

    Methods for the testing of the dielectric breakdown strength of insulation on metal wires under variable humidity conditions were developed. Two methods, an ASTM method and the twisted pair method, were compared to determine if the twisted pair method could be used for determination of breakdown strength under variable humidity conditions. It was concluded that, although there were small differences in outcomes between the two testing methods, the non-standard method (twisted pair) would be appropriate to use for further testing of the effects of humidity on breakdown performance. The dielectric breakdown strength of 34G copper wire insulated with double layer Poly-Thermaleze/Polyamide-imide insulation was measured using the twisted pair method under a variety of relative humidity (RH) conditions and exposure times. Humidity at 50% RH and below was not found to affect the dielectric breakdown strength. At 80% RH the dielectric breakdown strength was significantly diminished. No effect for exposure time up to 140 hours was observed at 50 or 80%RH.

  9. Direct synthesis of nitrogen-doped graphene on platinum wire as a new fiber coating method for the solid-phase microextraction of BXes in water samples: Comparison of headspace and cold-fiber headspace modes.

    Science.gov (United States)

    Memarian, Elham; Hosseiny Davarani, Saied Saeed; Nojavan, Saeed; Movahed, Siyavash Kazemi

    2016-09-07

    In this work, a new solid-phase microextraction fiber was prepared based on nitrogen-doped graphene (N-doped G). Moreover, a new strategy was proposed to solve problems dealt in direct coating of N-doped G. For this purpose, first, Graphene oxide (GO) was coated on Pt wire by electrophoretic deposition method. Then, chemical reduction of coated GO to N-doped G was accomplished by hydrazine and NH3. The prepared fiber showed good mechanical and thermal stabilities. The obtained fiber was used in two different modes (conventional headspace solid-phase microextraction and cold-fiber headspace solid-phase microextraction (CF-HS-SPME)). Both modes were optimized and applied for the extraction of benzene and xylenes from different aqueous samples. All effective parameters including extraction time, salt content, stirring rate, and desorption time were optimized. The optimized CF-HS-SPME combined with GC-FID showed good limit of detections (LODs) (0.3-2.3 μg/L), limit of quantifications (LOQs) (1.0-7.0 μg/L) and linear ranges (1.0-5000 μg/L). The developed method was applied for the analysis of benzene and xylenes in rainwater and some wastewater samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Development of an analytical method for crystalline content determination in amorphous solid dispersions produced by hot-melt extrusion using transmission Raman spectroscopy: A feasibility study.

    Science.gov (United States)

    Netchacovitch, L; Dumont, E; Cailletaud, J; Thiry, J; De Bleye, C; Sacré, P-Y; Boiret, M; Evrard, B; Hubert, Ph; Ziemons, E

    2017-09-15

    The development of a quantitative method determining the crystalline percentage in an amorphous solid dispersion is of great interest in the pharmaceutical field. Indeed, the crystalline Active Pharmaceutical Ingredient transformation into its amorphous state is increasingly used as it enhances the solubility and bioavailability of Biopharmaceutical Classification System class II drugs. One way to produce amorphous solid dispersions is the Hot-Melt Extrusion (HME) process. This study reported the development and the comparison of the analytical performances of two techniques, based on backscattering and transmission Raman spectroscopy, determining the crystalline remaining content in amorphous solid dispersions produced by HME. Principal Component Analysis (PCA) and Partial Least Squares (PLS) regression were performed on preprocessed data and tended towards the same conclusions: for the backscattering Raman results, the use of the DuoScan™ mode improved the PCA and PLS results, due to a larger analyzed sampling volume. For the transmission Raman results, the determination of low crystalline percentages was possible and the best regression model was obtained using this technique. Indeed, the latter acquired spectra through the whole sample volume, in contrast with the previous surface analyses performed using the backscattering mode. This study consequently highlighted the importance of the analyzed sampling volume. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Micro-scale prediction method for API-solubility in polymeric matrices and process model for forming amorphous solid dispersion by hot-melt extrusion.

    Science.gov (United States)

    Bochmann, Esther S; Neumann, Dirk; Gryczke, Andreas; Wagner, Karl G

    2016-10-01

    A new predictive micro-scale solubility and process model for amorphous solid dispersions (ASDs) by hot-melt extrusion (HME) is presented. It is based on DSC measurements consisting of an annealing step and a subsequent analysis of the glass transition temperature (Tg). The application of a complex mathematical model (BCKV-equation) to describe the dependency of Tg on the active pharmaceutical ingredient (API)/polymer ratio, enables the prediction of API solubility at ambient conditions (25°C). Furthermore, estimation of the minimal processing temperature for forming ASDs during HME trials could be defined and was additionally confirmed by X-ray powder diffraction data. The suitability of the DSC method was confirmed with melt rheological trials (small amplitude oscillatory system). As an example, ball milled physical mixtures of dipyridamole, indomethacin, itraconazole and nifedipine in poly(vinylpyrrolidone-co-vinylacetate) (copovidone) and polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer (Soluplus®) were used. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Fabrication of a Nano-ZnO/Polyethylene/Wood-Fiber Composite with Enhanced Microwave Absorption and Photocatalytic Activity via a Facile Hot-Press Method

    Directory of Open Access Journals (Sweden)

    Baokang Dang

    2017-11-01

    Full Text Available A polyethylene/wood-fiber composite loaded with nano-ZnO was prepared by a facile hot-press method and was used for the photocatalytic degradation of organic compounds as well as for microwave absorption. ZnO nanoparticles with an average size of 29 nm and polyethylene (PE powders were dispersed on the wood fibers’ surface through a viscous cationic polyacrylamide (CPAM solution. The reflection loss (RL value of the resulting composite was −21 dB, with a thickness of 3.5 mm in the frequency of 17.17 GHz. The PE/ZnO/wood-fiber (PZW composite exhibited superior photocatalytic activity (84% methyl orange degradation within 300 min under UV light irradiation. ZnO nanoparticels (NPs increased the storage modulus of the PZW composite, and the damping factor was transferred to the higher temperature region. The PZW composite exhibited the maximum flexural strength of 58 MPa and a modulus of elasticity (MOE of 9625 MPa. Meanwhile, it also displayed dimensional stability (thickness swelling value of 9%.

  13. Thermal Modeling of the Injection of Standard and Thermally Insulated Cored Wire

    Science.gov (United States)

    Castro-Cedeno, E.-I.; Jardy, A.; Carré, A.; Gerardin, S.; Bellot, J. P.

    2017-09-01

    Cored wire injection is a widespread method used to perform alloying additions during ferrous and non-ferrous liquid metal treatment. The wire consists of a metal casing that is tightly wrapped around a core of material; the casing delays the release of the material as the wire is immersed into the melt. This method of addition presents advantages such as higher repeatability and yield of cored material with respect to bulk additions. Experimental and numerical work has been performed by several authors on the subject of alloy additions, spherical and cylindrical geometries being mainly considered. Surprisingly this has not been the case for cored wire, where the reported experimental or numerical studies are scarce. This work presents a 1-D finite volume numerical model aimed for the simulation of the thermal phenomena which occurs when the wire is injected into a liquid metal bath. It is currently being used as a design tool for the conception of new types of cored wire. A parametric study on the effect of injection velocity and steel casing thickness for an Al cored wire immersed into a steel melt at 1863 K (1590 °C) is presented. The standard single casing wire is further compared against a wire with multiple casings. Numerical results show that over a certain range of injection velocities, the core contents' release is delayed in the multiple casing when compared to a single casing wire.

  14. Thermal Modeling of the Injection of Standard and Thermally Insulated Cored Wire

    Science.gov (United States)

    Castro-Cedeno, E.-I.; Jardy, A.; Carré, A.; Gerardin, S.; Bellot, J. P.

    2017-12-01

    Cored wire injection is a widespread method used to perform alloying additions during ferrous and non-ferrous liquid metal treatment. The wire consists of a metal casing that is tightly wrapped around a core of material; the casing delays the release of the material as the wire is immersed into the melt. This method of addition presents advantages such as higher repeatability and yield of cored material with respect to bulk additions. Experimental and numerical work has been performed by several authors on the subject of alloy additions, spherical and cylindrical geometries being mainly considered. Surprisingly this has not been the case for cored wire, where the reported experimental or numerical studies are scarce. This work presents a 1-D finite volume numerical model aimed for the simulation of the thermal phenomena which occurs when the wire is injected into a liquid metal bath. It is currently being used as a design tool for the conception of new types of cored wire. A parametric study on the effect of injection velocity and steel casing thickness for an Al cored wire immersed into a steel melt at 1863 K (1590 °C) is presented. The standard single casing wire is further compared against a wire with multiple casings. Numerical results show that over a certain range of injection velocities, the core contents' release is delayed in the multiple casing when compared to a single casing wire.

  15. Experimental and numeric study of aluminum wire explosion in vacuum

    Energy Technology Data Exchange (ETDEWEB)

    Tkachenko, S.I.; Khattatov, T.A.; Tilikin, I.N. [MIPT, Dolgoprudny, Moscow Region (Russian Federation); Romanova, V.M.; Mingaleev, A.R.; Ter-Oganesyan, A.E.; Shelkovenko, T.A.; Pikuz, S.A. [P.N. Lebedev Physical Institute RAS, Moscow (Russian Federation); Olhovskaya, O.G.; Krukovskij, A.Y.; Gasilov, V.A.; Novikov, V.G. [IMM RAS, Moscow (Russian Federation)

    2011-07-01

    .F. Nikiforov, V.G. Novikov, V.B. Uvarov, Quantum-Statistical Models of Hot Dense Matter and Methods for Computation Opacity and Equation of State. Fismatlit, Moscow, 2000. (authors)

  16. Wire chambers revisited.

    Science.gov (United States)

    Ott, R J

    1993-04-01

    Detectors used for radioisotope imaging have, historically, been based on scintillating crystal/photomultiplier combinations in various forms. From the rectilinear scanner through to modern gamma cameras and positron cameras, the basic technology has remained much the same. Efforts to overcome the limitations of this form of technology have foundered on the inability to reproduce the required sensitivity, spatial resolution and sensitive area at acceptable cost. Multiwire proportional chambers (MWPCs) have long been used as position-sensitive charged particle detectors in nuclear and high-energy physics. MWPCs are large-area gas-filled ionisation chambers in which large arrays of fine wires are used to measure the position of ionisation produced in the gas by the passage of charged particles. The important properties of MWPCs are high-spatial-resolution, large-area, high-count-rate performance at low cost. For research applications, detectors several metres square have been built and small-area detectors have a charged particle resolution of 0.4 mm at a count rate of several million per second. Modification is required to MWPCs for nuclear medicine imaging. As gamma rays or X-rays cannot be detected directly, they must be converted into photo- or Compton scatter electrons. Photon-electron conversion requires the use of high atomic number materials in the body of the chamber. Pressurised xenon is the most useful form of "gas only" photon-electron convertor and has been used successfully in a gamma camera for the detection of gamma rays at energies below 100 keV. This camera has been developed specifically for high-count-rate first-pass cardiac imaging. This high-pressure xenon gas MWPC is the key to a highly competitive system which can outperform scintillator-based systems. The count rate performance is close to a million counts per second and the intrinsic spatial resolution is better than the best scintillator-based camera. The MWPC camera produces quantitative

  17. Special wettable nanostructured copper mesh achieved by a facile hot water treatment process

    Science.gov (United States)

    Saadi, Nawzat S.; Hassan, Laylan B.; Brozak, Matt; Karabacak, Tansel

    2017-09-01

    In this research, a special wettable copper mesh with superhydrophobicity and superoleophilicity properties is reported using a low-cost, eco-friendly, rapid, and scalable synthesis method. Hot water treatment (HWT) method is used to integrate the micro-textured copper mesh surface with a nanoscale roughness to achieve a hierarchical micro-nano structured surface. The surface energy of the nanoscale roughened copper mesh reduced by coating the hot water treated mesh with polymer ligands containing thiol or fluorine functional groups of low energy. Surface morphology characterization showed the formation of copper oxide nanostructures on the mesh surface by hot water process performed at 95 °C and under a low dissolved oxygen condition. X-ray diffraction patterns reveal the development of stable, uniformly distributed, and compactly arranged, cubic and plate-like nanostructures of cuprous oxide (Cu2O) on the copper mesh surface. The surface wettability of the as-prepared copper mesh was assessed by contact angle (CA) measurement for water and several oils and organic solvents. CA values showed the formation of special wettable copper mesh surface with superhydrophobic property with water contact angle of about 157° and superoleophilic property with oil contact angle as low as 0°. In addition, the effect of the mesh’s geometry on the wetting property was examined through correlations between wire diameter, pore size, and optimal values for the highest water CA.

  18. Smokin` hot

    DEFF Research Database (Denmark)

    Mustonen, A; Ahokas, T; Nordström, T

    2018-01-01

    OBJECTIVE: Daily smoking has been associated with a greater risk of psychosis. However, we are still lacking studies to adjust for baseline psychotic experiences and other substance use. We examined associations between daily smoking and psychosis risk in a 15-year follow-up while accounting for ...... cigarettes increased psychosis risk in a dose-response manner (adjusted OR = 1.05; 1.01-1.08). CONCLUSION: Heavy tobacco smoking in adolescence was associated with a greater risk for psychosis even after adjustment for confounders.......OBJECTIVE: Daily smoking has been associated with a greater risk of psychosis. However, we are still lacking studies to adjust for baseline psychotic experiences and other substance use. We examined associations between daily smoking and psychosis risk in a 15-year follow-up while accounting...... for these covariates in a prospective sample (N = 6081) from the Northern Finland Birth Cohort 1986. METHODS: Self-report questionnaires on psychotic experiences (PROD-screen), tobacco smoking and other substance use were completed when the cohort members were 15-16 years old. Tobacco smoking was categorized...

  19. Aging analyses of aircraft wire insulation

    Energy Technology Data Exchange (ETDEWEB)

    GILLEN,KENNETH T.; CLOUGH,ROGER LEE; CELINA,MATHIAS C.; AUBERT,JAMES H.; MALONE,G. MICHAEL

    2000-05-08

    Over the past two decades, Sandia has developed a variety of specialized analytical techniques for evaluating the long-term aging and stability of cable insulation and other related materials. These techniques have been applied to cable reliability studies involving numerous insulation types and environmental factors. This work has allowed the monitoring of the occurrence and progression of cable material deterioration in application environments, and has provided insights into material degradation mechanisms. It has also allowed development of more reliable lifetime prediction methodologies. As a part of the FAA program for intrusive inspection of aircraft wiring, they are beginning to apply a battery of techniques to assessing the condition of cable specimens removed from retired aircraft. It is anticipated that in a future part of this program, they may employ these techniques in conjunction with accelerated aging methodologies and models that the authros have developed and employed in the past to predict cable lifetimes. The types of materials to be assessed include 5 different wire types: polyimide, PVC/Glass/Nylon, extruded XL-polyalkene/PVDF, Poly-X, and XL-ETFE. This presentation provides a brief overview of the main techniques that will be employed in assessing the state of health of aircraft wire insulation. The discussion will be illustrated with data from their prior cable aging studies, highlighting the methods used and their important conclusions. A few of the techniques that they employ are widely used in aging studies on polymers, but others are unique to Sandia. All of their techniques are non-proprietary, and maybe of interest for use by others in terms of application to aircraft wiring analysis. At the end of this report is a list showing some leading references to papers that have been published in the open literature which provide more detailed information on the analytical techniques for elastomer aging studies. The first step in the

  20. Laser Indirect Shock Welding of Fine Wire to Metal Sheet

    Science.gov (United States)

    Wang, Xiao; Huang, Tao; Luo, Yapeng; Liu, Huixia

    2017-01-01

    The purpose of this paper is to present an advanced method for welding fine wire to metal sheet, namely laser indirect shock welding (LISW). This process uses silica gel as driver sheet to accelerate the metal sheet toward the wire to obtain metallurgical bonding. A series of experiments were implemented to validate the welding ability of Al sheet/Cu wire and Al sheet/Ag wire. It was found that the use of a driver sheet can maintain high surface quality of the metal sheet. With the increase of laser pulse energy, the bonding area of the sheet/wire increased and the welding interfaces were nearly flat. Energy dispersive spectroscopy (EDS) results show that the intermetallic phases were absent and a short element diffusion layer which would limit the formation of the intermetallic phases emerging at the welding interface. A tensile shear test was used to measure the mechanical strength of the welding joints. The influence of laser pulse energy on the tensile failure modes was investigated, and two failure modes, including interfacial failure and failure through the wire, were observed. The nanoindentation test results indicate that as the distance to the welding interface decreased, the microhardness increased due to the plastic deformation becoming more violent. PMID:28895900

  1. Plasma arc torch with coaxial wire feed

    Science.gov (United States)

    Hooper, Frederick M

    2002-01-01

    A plasma arc welding apparatus having a coaxial wire feed. The apparatus includes a plasma arc welding torch, a wire guide disposed coaxially inside of the plasma arc welding torch, and a hollow non-consumable electrode. The coaxial wire guide feeds non-electrified filler wire through the tip of the hollow non-consumable electrode during plasma arc welding. Non-electrified filler wires as small as 0.010 inches can be used. This invention allows precision control of the positioning and feeding of the filler wire during plasma arc welding. Since the non-electrified filler wire is fed coaxially through the center of the plasma arc torch's electrode and nozzle, the wire is automatically aimed at the optimum point in the weld zone. Therefore, there is no need for additional equipment to position and feed the filler wire from the side before or during welding.

  2. Ocular dangers of fencing wire.

    Science.gov (United States)

    McAllum, P; Barnes, R; Dickson, J

    2001-07-27

    To invesitgate the incidence and severity of penetrating eye injuries caused by fencing wire in the Waikato region. We reviewed the case notes for all penetrating eye injuries treated at Waikato Hospital during the past six years. Parameters recorded were patient age and sex, mechanism of injury, initial visual acuity, characteristics of injury, surgery performed and final visual outcome. The incidence of penetrating eye injuries in the Waikato region was 3.8 per 100,000 per year, based on an estimated catchment population of 350,000. We found fencing wire to be the third most common cause of penetrating eye injury, accounting for 8.8% of injuries, behind motor vehicle accidents and hammering which accounted for 26.3% and 20.0% of injuries, respectively. The fencing wire injuries involved men exclusively, with an average age of 41.7 years. Fencing wire injuries had worse presenting visual acuity than other injuries, involved the posterior segment of the eye more frequently and were more likely to develop bacterial endophthalmitis. They also underwent more surgical procedures and were more commonly associated with a poor visual outcome. Fencing wire is an important cause of visual loss in the Waikato region. We hope to raise awareness of its potential ocular dangers and to promote the use of appropriate eye protection.

  3. Hot Blade Cuttings for the Building Industries

    DEFF Research Database (Denmark)

    Brander, David; Bærentzen, Jakob Andreas; Evgrafov, Anton

    2016-01-01

    variability in the (economically allowed) designs - i.e., to allow them to think out of the box. To address this challenge The Danish National Advanced Technology Foundation (now InnovationsFonden) is currently supporting the BladeRunner project that involves several Danish companies and public institutions....... The project aims to reduce the amount of manual labour as well as production time by applying robots to cut expanded polystyrene (EPS) moulds for the concrete to form doubly curved surfaces. The scheme is based upon the so-called Hot Wire or Hot Blade technology where the surfaces are essentially swept out...... are mainly concerned with the rationalization of the architects’ CAD drawings into surfaces that can be created via this particular sweeping and cutting technology....

  4. A debugging method of the Quadrotor UAV based on infrared thermal imaging

    Science.gov (United States)

    Cui, Guangjie; Hao, Qian; Yang, Jianguo; Chen, Lizhi; Hu, Hongkang; Zhang, Lijun

    2018-01-01

    High-performance UAV has been popular and in great need in recent years. The paper introduces a new method in debugging Quadrotor UAVs. Based on the infrared thermal technology and heat transfer theory, a UAV is under debugging above a hot-wire grid which is composed of 14 heated nichrome wires. And the air flow propelled by the rotating rotors has an influence on the temperature distribution of the hot-wire grid. An infrared thermal imager below observes the distribution and gets thermal images of the hot-wire grid. With the assistance of mathematic model and some experiments, the paper discusses the relationship between thermal images and the speed of rotors. By means of getting debugged UAVs into test, the standard information and thermal images can be acquired. The paper demonstrates that comparing to the standard thermal images, a UAV being debugging in the same test can draw some critical data directly or after interpolation. The results are shown in the paper and the advantages are discussed.

  5. Silicon Sheet Growth Development for the Large Area Sheet Task of the Low Cost Solar Array Project. Heat Exchanger Method - Ingot Casting Fixed Abrasive Method - Multi-Wire Slicing

    Science.gov (United States)

    Schmid, F.; Khattak, C. P.

    1978-01-01

    Solar cells fabricated from HEM cast silicon yielded up to 15% conversion efficiencies. This was achieved in spite of using unpurified graphite parts in the HEM furnace and without optimization of material or cell processing parameters. Molybdenum retainers prevented SiC formation and reduced carbon content by 50%. The oxygen content of vacuum cast HEM silicon is lower than typical Czochralski grown silicon. Impregnation of 45 micrometers diamonds into 7.5 micrometers copper sheath showed distortion of the copper layer. However, 12.5 micrometers and 15 micrometers copper sheath can be impregnated with 45 micrometers diamonds to a high concentration. Electroless nickel plating of wires impregnated only in the cutting edge showed nickel concentration around the diamonds. This has the possibility of reducing kerf. The high speed slicer fabricated can achieve higher speed and longer stroke with vibration isolation.

  6. Migration of a Kirschner wire to the dorsolateral side of the foot following osteosynthesis of a patella fracture with tension band wiring: a case report.

    Science.gov (United States)

    Aydın, Ekrem; Dülgeroğlu, Turan Cihan; Metineren, Hasan

    2016-02-24

    Patella fractures represent 1 % of all musculoskeletal system fractures. Fixation of patellar fractures using open reduction and tension band wiring is a commonly used and successful surgical fixation method. A 28-year-old male patient from Turkey presented to our clinic with complaints of palpable foreign bodies under the skin on the dorsolateral side of his right foot. Except for the palpable and moving body of about 6 cm length under the skin in his foot, he had no functional complaints. On X-ray, a Kirschner wire was visible in front of the lateral malleolus on the dorsolateral side of his right foot. In addition, there was a cerclage wire from the tension band fixation of his patella in the ipsilateral knee. The Kirschner wire was removed surgically. Despite the use of different fixation materials for the surgical treatment of patellar fractures, tension band wiring is still a commonly used technique. We recommend that after fixation of a patellar fracture using the tension band wiring technique, the ends of the Kirschner wires be bent and the wires then removed in the early phase after patellar union to prevent Kirschner wire migration.

  7. Weyl fermions in cylindrical wires

    Science.gov (United States)

    Erementchouk, Mikhail; Mazumder, Pinaki

    2018-01-01

    The key feature of Weyl semimetals (WSMs) is the presence of topologically protected Dirac cones in a three-dimensional material. We consider the effect of restricting geometry on the spectrum of excitations in WSMs using as a model a cylindrical WSM wire. For the full manifold of hard boundary conditions, we derive the general form of the dispersion equation relating the energy of the excitations and their momentum along the wire. We show that only the special class of boundary conditions, corresponding to decoupled helicities or, equivalently, to pinned directions of the electron spin on the surface, support massless excitations. For a general boundary condition, these excitations acquire mass inversely proportional to the radius of the wire. This demonstrates that boundary phenomena may play a crucial role in formation of excitations in WSM based structures.

  8. Experimental study on manufacturing of grits-spiral- distribution electroplated wire saw

    Directory of Open Access Journals (Sweden)

    Yufei GAO

    2016-12-01

    Full Text Available In order to obtain high performance electroplating diamond wire saw, experimental studies are conducted for development of grits-spiral-distribution electroplated diamond wire saw using sand-suspend electroplating method. The influences of pre-plating cathode current density, grits electro-embedding cathode current density and time on composite deposite coating appearance and grits distribution of wire saw are analyzed, and the sawing experiment is carried out by using the trial wire saw. The results show that good bonding strength between the coating and the steel wire can be obtained when the adopted cathode current density is 5.0 A/dm2 at pre-plating stage; good coating and girts distribution can be obtained when the adopted cathode current density is 5.0 A/dm2 and the electroplating time is 7~8 min at grits electro-embedding stage. By winding insulation wire on the surface of steel wire and reasonably selecting technological parameters before pre-plating can make the diamond wire saw with grits-spiral-distribution on surface, and the new type of wire saw has a better crumbs-clearing effect in wire sawing process.

  9. Review of effects of dielectric coatings on electrical exploding wires and Z pinches

    Science.gov (United States)

    Wu, Jian; Li, Xingwen; Li, Mo; Li, Yang; Qiu, Aici

    2017-10-01

    As the most powerful x-ray source in the laboratories, the wire array Z pinches have been of great relevance to inertial confinement fusions, laboratory astrophysics, and other high-energy density applications. In order to produce x-ray with greater power and higher efficiency, the dynamics of wire array has been investigated extensively, and various methods have been proposed to improve the implosion quality of the wire array. This review focuses on the experimental and theoretical investigations regarding the effects of the dielectric coatings on electrical exploding wires and Z pinches. Since the early 2000, the electrical wire explosion related to the first stage of the wire array Z pinches has been studied extensively, and the results indicated that the dielectric coatings can significantly increase the joule energy deposition into a wire in the initial stage, and even the corona free explosion of tungsten wires can be achieved. Recently, there is an increasing interest in the dynamics of insulated wire array Z pinches. By applying dielectric coatings, the ablation process is suppressed, the x-ray start time is delayed, and the possibility of multi-peak radiation is decreased. This review is organized by the evolution dynamics of wire array Z pinches, and a broad introduction to relevant scientific concepts and various other applications are presented. According to the current research status, the challenges, opportunities and further developments of Z pinch loads using dielectric coatings are proposed to further promote the researches and their applications.

  10. Thermal conductivity measurements of high and low thermal conductivity films using a scanning hot probe method in the 3ω mode and novel calibration strategies.

    Science.gov (United States)

    Wilson, Adam A; Muñoz Rojo, Miguel; Abad, Begoña; Perez, Jaime Andrés; Maiz, Jon; Schomacker, Jason; Martín-Gonzalez, Marisol; Borca-Tasciuc, Diana-Andra; Borca-Tasciuc, Theodorian

    2015-10-07

    This work discusses measurement of thermal conductivity (k) of films using a scanning hot probe method in the 3ω mode and investigates the calibration of thermal contact parameters, specifically the thermal contact resistance (R(th)C) and thermal exchange radius (b) using reference samples with different thermal conductivities. R(th)C and b were found to have constant values (with b = 2.8 ± 0.3 μm and R(th)C = 44,927 ± 7820 K W(-1)) for samples with thermal conductivity values ranging from 0.36 W K(-1) m(-1) to 1.1 W K(-1) m(-1). An independent strategy for the calibration of contact parameters was developed and validated for samples in this range of thermal conductivity, using a reference sample with a previously measured Seebeck coefficient and thermal conductivity. The results were found to agree with the calibration performed using multiple samples of known thermal conductivity between 0.36 and 1.1 W K(-1) m(-1). However, for samples in the range between 16.2 W K(-1) m(-1) and 53.7 W K(-1) m(-1), calibration experiments showed the contact parameters to have considerably different values: R(th)C = 40,191 ± 1532 K W(-1) and b = 428 ± 24 nm. Finally, this work demonstrates that using these calibration procedures, measurements of both highly conductive and thermally insulating films on substrates can be performed, as the measured values obtained were within 1-20% (for low k) and 5-31% (for high k) of independent measurements and/or literature reports. Thermal conductivity results are presented for a SiGe film on a glass substrate, Te film on a glass substrate, polymer films (doped with Fe nano-particles and undoped) on a glass substrate, and Au film on a Si substrate.

  11. Adhesion strength study of IBAD-MOCVD-based 2G HTS wire using a peel test

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Y., E-mail: yzhang@superpower-inc.com [SuperPower Inc., 450 Duane Avenue, Schenectady, NY 12304 (United States); Hazelton, D.W.; Knoll, A.R.; Duval, J.M.; Brownsey, P.; Repnoy, S.; Soloveichik, S.; Sundaram, A.; McClure, R.B. [SuperPower Inc., 450 Duane Avenue, Schenectady, NY 12304 (United States); Majkic, G.; Selvamanickam, V. [University of Houston, 4800 Calhoun Road, Houston, TX 77204 (United States)

    2012-02-15

    A peel test was used to study the adhesion strength of a commercial grade 2G HTS wire which features a characteristic multilayer structure with the rare earth-based MOCVD superconducting film deposited on an IBAD-MgO template. The peel test could be carried out at various peeling angles (from 90 Degree-Sign to 180 Degree-Sign) and the peel strength of a wire was defined as the steady-state peeling load determined from a load-displacement curve. The test results had good reproducibility and accuracy, making the test a reliable and useful method for studying the adhesion strength of the wire. By characterizing the peeled surfaces the weakest interface in a wire could be identified. The peel strength data of the wire was analyzed together with the performance of the experimental magnet coils fabricated using the wire. The effect of the silver contact layer annealing on the peel strength is discussed.

  12. Fulleropyrrolidine end-capped molecular wires for molecular electronics--synthesis, spectroscopic, electrochemical, and theoretical characterization

    DEFF Research Database (Denmark)

    Sørensen, Jakob Kryger; Fock, Jeppe; Pedersen, Anders Holmen

    2011-01-01

    In continuation of previous studies showing promising metal-molecule contact properties a variety of C(60) end-capped "molecular wires" for molecular electronics were prepared by variants of the Prato 1,3-dipolar cycloaddition reaction. Either benzene or fluorene was chosen as the central wire......-withdrawing ester group present. The effect of extending the p-system of the central wire from 1,4-phenylenediamine to 2,7-fluorenediamine was investigated by absorption, fluorescence, and electrochemical methods. The central wire and the C(60) end-groups were found not to electronically communicate in the ground...... state. However, the fluorescence of C(60) was quenched by charge transfer from the wire to C(60). Quantum chemical calculations predict and explain the collapse of coherent electronic transmission through one of the fulleropyrrolidine-terminated molecular wires....

  13. Prediction of multi performance characteristics of wire EDM process using grey ANFIS

    Science.gov (United States)

    Kumanan, Somasundaram; Nair, Anish

    2017-09-01

    Super alloys are used to fabricate components in ultra-supercritical power plants. These hard to machine materials are processed using non-traditional machining methods like Wire cut electrical discharge machining and needs attention. This paper details about multi performance optimization of wire EDM process using Grey ANFIS. Experiments are designed to establish the performance characteristics of wire EDM such as surface roughness, material removal rate, wire wear rate and geometric tolerances. The control parameters are pulse on time, pulse off time, current, voltage, flushing pressure, wire tension, table feed and wire speed. Grey relational analysis is employed to optimise the multi objectives. Analysis of variance of the grey grades is used to identify the critical parameters. A regression model is developed and used to generate datasets for the training of proposed adaptive neuro fuzzy inference system. The developed prediction model is tested for its prediction ability.

  14. Effect of Sintering Time on Superconducting Wire Bi-Pb-Sr-Ca-Cu-O With Dopant MgO Sheated Ag Using Powder in Tube Method

    Directory of Open Access Journals (Sweden)

    Hariyati Lubis

    2018-01-01

      DAFTAR PUSTAKA Abbas M.M., Abass L.K and Salman U., (2012, Influences of Sintering Time on the Tc of Bi2-xCuxPb0.3Sr2Ca2Cu3010+ High Temperature Superconductors, Energy Procedia 18, 215-224  Abbas, M.M., Abbas, L.K., Bahedh, H.S. 2015. Superconducting Properties of Bi2-SbxPb0,3Sr1,9Ba0,1Ca2Cu3O10+δ Compounds. Journal of Applied Science Research. 11. 22: 164-172 Darsono, N., Imaduddin, A., Raju, K., Yoon, D.H., (2015, Synthesis and Characterization of Bi1.6Pb0.4Sr2Ca2Cu3O7 Superconducting Oxide by High-Energy Milling, J Supercond Nov Magn. E. Chew,. (2010, Superconducting Transformer Design And Construction, University of Canterbury, Christchurch, New Zealand. March Hamadneh, I., Halim, S. A., dan Lee, C. K., (2006,  Characterization of Bi1.6Pb0.4Sr2Ca2Cu3Oy Ceramic Superconductor Prepared Via Coprecipitation Method at Different Sintering Time, J. Mater. Sci, 41: 5526-5530. Hermiz G.Y., Aljurani B.A., Beayaty M.A., (2014, Effect of Mn Substitution on the Superconducting Properties of Bi1.7Pb0,3Sr2Ca2-xMnxCu3O10+, International Journal Of Engineering and Advanced Technology (IJEAT. 3. 4: 213-217 John R Hull, (2003, Applications of high-temperature superconductors in power technology, Reports on Progress in Physics, Volume 66, Number 11 Lu, X.Y., Yi, D., Chen, H., Nagata, A. 2016. Effect of Sn, MgO and Ag2O mix-doping on the formation and superconducting properties of Bi-2223 Ag/tapes. Physics Procedia. 81: 129-132 Meretliev Sh., Sadykov K.B., Berkeliev A., (2000, Doping of High Temperature Superconductors, Turk J Phy.24: 39-48 Mohammed, N. H., Ramadhan A., Ali I. A., Ibrahim, I. H., dan Hassan, M. S, (2012, Optimizing the Preparation Conditions of Bi-2223 Superconducting Phase Using PbO and PbO2, Materials Sciences and Applications, 3: 224-233. Roumie, M., Marhaba, S., Awad R., Kork M., Hassan I., Mawassi R., (2014, Effect of Fe2O3 Nano-Oxide Addition on the Superconducting Properties of the (Bi,Pb-2223 Phase, Journal of Supercond Nov Magn, 27: 143-153 Serkan

  15. Magnetic measurement with coils and wires

    CERN Document Server

    Walckiers, L

    2010-01-01

    Accelerator magnets steer particle beams according to the field integrated along the trajectory over the magnet length. Purpose-wound coils measure these relevant parameters with high precision and complement efficiently point-like measurements performed with Hall plates or NMR probes. The rotating coil method gives a complete two-dimensional description of the magnetic field in a series of normal and skew multipoles. The more recent single stretched wire is a reference instrument to measure field integrals and to find the magnetic axis.

  16. Subchannel Analysis of Wire Wrapped SCWR Assembly

    National Research Council Canada - National Science Library

    Shan, Jianqiang; Wang, Henan; Liu, Wei; Song, Linxing; Chen, Xuanxiang; Jiang, Yang

    2014-01-01

    .... The HPLWR wire wrapped assembly was analyzed. The results show that: (1) the assembly with wire wrap can obtain a more uniform coolant temperature profile than the grid spaced assembly, which will result in a lower peak cladding temperature; (2...

  17. Guide to the IET wiring regulations BS 7671:2008 incorporating amendment no 1:2011)

    CERN Document Server

    2012-01-01

    This authoritative, best-selling guide has been extensively updated with the new technical requirements of the IET Wiring Regulations (BS 7671: 2008) Amendment No. 1:2011, also known as the IET Wiring Regulations 17th Edition. With clear description, it provides a practical interpretation of the amended regulations - effective January 2012 - offers real solutions to the problems that can occur in practice. This revised edition features:new material on hot topics such as electromagnetic compatibility (EMC), harmonics, surge protective devices, and new special locations incl

  18. Signal shapes in a TPC wire chamber

    Science.gov (United States)

    Rossegger, S.; Riegler, W.

    2010-11-01

    We study signal shapes in Multi Wire Proportional Chambers (MWPCs) and the influence of the electron distribution around the wire on the ion tail characteristics. Simulations of the ion tail for two different geometries, different voltages and therefore gas gains were performed. These simulations are compared to measurements carried out with the ALICE TPC wire chambers for a Ne/CO 2/N 2 gas mixture, which allows to extract the avalanche spread around the anode wires of the MWPC.

  19. Towards Unconventional Applications of Wire Bonding

    OpenAIRE

    Schröder, Stephan

    2018-01-01

    This thesis presents novel heterogeneous integration approaches of wire materials to fabricated and package MEMS devices by exploring unconventional applications of wire bonding technology. Wire bonding, traditionally endemic in the realm of device packaging to establish electrical die-to-package interconnections, is an attractive back-end technology, offering promising features, such as high throughput, flexibility and placement accuracy. Exploiting the advantages of state-of-the-art wire bo...

  20. Novel Wiring Technologies for Aerospace Applications

    Science.gov (United States)

    Gibson, Tracy L.; Parrish, Lewis M.

    2014-01-01

    Because wire failure in aerospace vehicles could be catastrophic, smart wiring capabilities have been critical for NASA. Through the years, researchers at Kennedy Space Center (KSC) have developed technologies, expertise, and research facilities to meet this need. In addition to aerospace applications, NASA has applied its knowledge of smart wiring, including self-healing materials, to serve the aviation industry. This webinar will discuss the development efforts of several wiring technologies at KSC and provide insight into both current and future research objectives.

  1. Electron transport in stretched monoatomic gold wires.

    Science.gov (United States)

    Grigoriev, A; Skorodumova, N V; Simak, S I; Wendin, G; Johansson, B; Ahuja, R

    2006-12-08

    The conductance of monoatomic gold wires containing 3-7 gold atoms has been obtained from ab initio calculations. The transmission is found to vary significantly depending on the wire stretching and the number of incorporated atoms. Such oscillations are determined by the electronic structure of the one-dimensional (1D) part of the wire between the contacts. Our results indicate that the conductivity of 1D wires can be suppressed without breaking the contact.

  2. Detection of a buried wire with two resistively loaded wire antennas

    NARCIS (Netherlands)

    Vossen, S.H.J.A.; Tijhuis, A.G.; Lepelaars, E.S.A.M.; Zwamborn, A.P.M.

    2002-01-01

    The use of two identical straight thin-wire antennas for the detection of a buried wire is analyzed with the aid of numerical calculations. The buried wire is located below an interface between two homogeneous half-spaces. The detection setup, which is formed by a transmitting and a receiving wire,

  3. One century of Kirschner wires and Kirschner wire insertion techniques : A historical review

    NARCIS (Netherlands)

    Franssen, Bas B. G. M.; Schuurman, Arnold H.; Van der Molen, Aebele Mink; Kon, Moshe

    A century ago, in 1909, Martin Kirschner (1879-942) introduced a smooth pin, presently known as the Kirschner wire (K-wire). The K-wire was initiallly used for skeletal traction and is now currently used for many different goals. The development of the K-wire and its insertion devices were mainly

  4. Real-time logic modelling on SpaceWire

    Science.gov (United States)

    Zhou, Qiang; Ma, Yunpeng; Fei, Haidong; Wang, Xingyou

    2017-04-01

    A SpaceWire is a standard for on-board satellite networks as the basis for future data-handling architectures. However, it cannot meet the deterministic requirement for safety/time critical application in spacecraft, where the delay of real-time (RT) message streams must be guaranteed. Therefore, SpaceWire-D is developed that provides deterministic delivery over a SpaceWire network. Formal analysis and verification of real-time systems is critical to their development and safe implementation, and is a prerequisite for obtaining their safety certification. Failure to meet specified timing constraints such as deadlines in hard real-time systems may lead to catastrophic results. In this paper, a formal verification method, Real-Time Logic (RTL), has been proposed to specify and verify timing properties of SpaceWire-D network. Based on the principal of SpaceWire-D protocol, we firstly analyze the timing properties of fundamental transactions, such as RMAP WRITE, and RMAP READ. After that, the RMAP WRITE transaction structure is modeled in Real-Time Logic (RTL) and Presburger Arithmetic representations. And then, the associated constraint graph and safety analysis is provided. Finally, it is suggested that RTL method can be useful for the protocol evaluation and provision of recommendation for further protocol evolutions.

  5. Home and School Technology: Wired versus Wireless.

    Science.gov (United States)

    Van Horn, Royal

    2001-01-01

    Presents results of informal research on smart homes and appliances, structured home wiring, whole-house audio/video distribution, hybrid cable, and wireless networks. Computer network wiring is tricky to install unless all-in-one jacketed cable is used. Wireless phones help installers avoid pre-wiring problems in homes and schools. (MLH)

  6. Electrochemistry of surface wired cytochrome c and ...

    Indian Academy of Sciences (India)

    Pyrazine unit in the mixed self-assembly promotes the electron transfer in the redox reaction of surface wired Cyt-c. Cyt-c wired on the mixed self-assembly has been used for the amperometric sensing of superoxide. The enzymatically generated superoxide has been successfully detected using the Cyt-c wired electrode.

  7. 49 CFR 393.28 - Wiring systems.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false Wiring systems. 393.28 Section 393.28 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL MOTOR CARRIER SAFETY... NECESSARY FOR SAFE OPERATION Lamps, Reflective Devices, and Electrical Wiring § 393.28 Wiring systems...

  8. Customised 2G HTS wire for applications

    Science.gov (United States)

    Samoilenkov, S.; Molodyk, A.; Lee, S.; Petrykin, V.; Kalitka, V.; Martynova, I.; Makarevich, A.; Markelov, A.; Moyzykh, M.; Blednov, A.

    2016-02-01

    Reproducibility of superconducting properties and suitability for specific applications by means of customised finish are two important attributes required from commercial 2G HTS wire. This paper reviews the consistent performance of SuperOx production 2G HTS wire and describes two novel customisation options: surround polyimide varnish insulation and composite bulk materials assembled with 2G HTS wires soldered together.

  9. Thermal imaging of hot spots in nanostructured microstripes

    Energy Technology Data Exchange (ETDEWEB)

    Saidi, E; Lesueur, J; Aigouy, L [LPEM, CNRS UPR5, ESPCI, 10 rue Vauquelin, 75231 Paris Cedex 5 (France); Labeguerie-Egea, J; Mortier, M, E-mail: lionel.aigouy@espci.f [LCMCP, CNRS UMR 7574, ENSCP, 11 rue P. et M. Curie, 75005 Paris (France)

    2010-03-01

    By scanning thermal microscopy, we study the behavior of nanostructured metallic microstripes heated by Joule effect. Regularly spaced indentations have been made along the thin film stripe in order to create hot spots. For the designed stripe geometry, we observe that heat remains confined in the wire and in particular at shrinkage points within {approx}1{mu}m{sup 2}. Thermal maps have been obtained with a good lateral resolution (< 300nm) and a good temperature sensitivity ({approx}1K).

  10. Gold Wire-networks: Particle Array Guided Evaporation Lithograpy

    KAUST Repository

    Lone, Saifullah

    2015-06-29

    We exploited the combination of dry deposition of monolayer of 2D (two dimensional) templates, lift-up transfer of 2D template onto flat surfaces and evaporation lithography [1] to fabricate gold micro- and submicron size wire networks. The approach relies upon the defect free dry deposition of 2D monolayer of latex particles [2] on patterned silicon template and flat PDMS-substrate to create square centered and honey-comb wire networks respectively. The process is followed by lift-up transfer of 2D latex crystal on glass substrate. Subsequently, a small amount of AuNP-suspension is doped on top of the transferred crystal; the suspension is allowed to spread instantaneously and dried at low temperature. The liquid evaporates uniformly to the direction perpendicular to glass substrate. During evaporation, AuNPs are de-wetted along with the movement of liquid to self-assemble in-between the inter-particle spaces and therefore, giving rise to liquid-bridge networks which upon delayed evaporation, transforms into wire networks. The approach is used to fabricate both micro- and submicron wire-networks by simply changing the template dimensions. One of the prime motives behind this study is to down-scale the existing particle array template-based evaporation lithography process to fabricate connected gold wire networks at both micro- and submicron scale. Secondly, the idea of combining the patterned silicon wafer with lifted latex particle template creates an opportunity to clean and res-use the patterned wafer more often and thereby, saving fabrication time and resources. Finally, we illustrated the validity of this approach by creating an easy and high-speed approach to develop gold wire networks on a flexible substrate with a thin deposited adhesive. These advances will not only serve as a platform to scale up the production, but also demonstrated that the fabrication method can produce metallic wire networks of different scale and onto a variety of substrates.

  11. Hot, Dry and Cloudy

    Science.gov (United States)

    2007-01-01

    [figure removed for brevity, see original site] Click on the image for movie of Hot, Dry and Cloudy This artist's concept shows a cloudy Jupiter-like planet that orbits very close to its fiery hot star. NASA's Spitzer Space Telescope was recently used to capture spectra, or molecular fingerprints, of two 'hot Jupiter' worlds like the one depicted here. This is the first time a spectrum has ever been obtained for an exoplanet, or a planet beyond our solar system. The ground-breaking observations were made with Spitzer's spectrograph, which pries apart infrared light into its basic wavelengths, revealing the 'fingerprints' of molecules imprinted inside. Spitzer studied two planets, HD 209458b and HD 189733b, both of which were found, surprisingly, to have no water in the tops of their atmospheres. The results suggest that the hot planets are socked in with dry, high clouds, which are obscuring water that lies underneath. In addition, HD209458b showed hints of silicates, suggesting that the high clouds on that planet contain very fine sand-like particles. Capturing the spectra from the two hot-Jupiter planets was no easy feat. The planets cannot be distinguished from their stars and instead appear to telescopes as single blurs of light. One way to get around this is through what is known as the secondary eclipse technique. In this method, changes in the total light from a so-called transiting planet system are measured as a planet is eclipsed by its star, vanishing from our Earthly point of view. The dip in observed light can then be attributed to the planet alone. This technique, first used by Spitzer in 2005 to directly detect the light from an exoplanet, currently only works at infrared wavelengths, where the differences in brightness between the planet and star are less, and the planet's light is easier to pick out. For example, if the experiment had been done in visible light, the total light from the system would appear to be unchanged, even as the planet

  12. 3D modeling of thin wires interacting with thin plates: Extracting the singularity due to the loop wire self inductance

    Science.gov (United States)

    Abakar, A.; Meunier, G.; Coulomb, J.-L.; Zgainski, F.-X.

    2001-04-01

    The 3D modeling of thin structures by the finite element method leads to a high number of elements or elements of bad quality, which yields to badly conditioned problems. For the thin plates, shell formulations have been used by several authors. In the case of thin wires, we use a model of unmeshed conductor in which the current is unknown. Physics characteristics: resistance, inductance are integrated in the circuit equation. This article presents a method that extracts the inductance computation which introduced a singularity in the case of thin wires.

  13. Determination of the initial exothermic reaction of shredded tyres with wire content.

    Science.gov (United States)

    Sellasie, Kassahun G; Moo-Young, Horace K; Lloyd, Thomas

    2004-10-01

    This paper presents the cause of exothermic reactions in shredded tyre with exposed wire content in shredded tyre piles. Data indicate that the oxidation of exposed steel wires is the exothermic reaction in shredded tyre embankments. This would lead to spontaneous combustion. Reaction of the steel with the sulphur or the carbon black appears not to be the source of the exothermic. Laboratory tests have been conducted to determine the heat transfer properties of the materials that compose tyres (i.e., tyre rubber and wires) by using a hot-plate apparatus. In addition, one-dimensional heat conduction experiments were conducted to compare the flow of heat through the materials while varying the physical and environmental conditions. The physical conditions were the size of tyre shred, water content, and wire contents. An exothermic reaction occurred when exposed wire was present but not when it was absent. A one-dimensional heat transfer equation was developed, and parametric studies were conducted to verify the laboratory model. Exothermic reaction was found to increase linearly with temperature, size and shape of the shredded tyres, density, amount of wire in shredded tyres, and water content.

  14. Technology of producing fibrous structure wire from chips of aluminum–magnesium–silicon alloys

    OpenAIRE

    Zagirov, N.; Kovalyova, A.; Ivanov, E.

    2010-01-01

    A technological scheme for processing the scrap of aluminum–magnesium–silicon alloy in the form of friable chips into rods and wire is introduced. This scheme is based on the powder metallurgy methods. The characteristic structure and the level of mechanical properties of the produced wire are denoted.

  15. Single- and multi-filamentary Fe-sheathed MgB{sub 2} wires

    Energy Technology Data Exchange (ETDEWEB)

    Zhou Sihai; Pan, Alexey V.; Liu Huakun; Dou Shixue

    2002-11-15

    A novel method is proposed to increase the MgB{sub 2} core density and, as a consequence, the critical current density of Fe-sheathed MgB{sub 2} wires. This method involves two additional stages compared to the usual wire fabrication: post-annealing mechanical deformation and a consecutive heat-treatment. Using this method we obtained denser core structures in 7-filament wire having J{sub c} values larger by a factor of about 4.3 than that found in the initial 'in situ' prepared mono-core wire. Independent of the manufacturing procedure, the wires showed a transport property degradation effect after being exposed to the air for 4 months.

  16. Emittance growth due to Tevatron flying wires

    Energy Technology Data Exchange (ETDEWEB)

    Syphers, M; Eddy, Nathan

    2004-06-01

    During Tevatron injection, Flying Wires have been used to measure the transverse beam size after each transfer from the Main Injector in order to deduce the transverse emittances of the proton and antiproton beams. This amounts to 36 + 9 = 45 flies of each of 3 wire systems, with an individual wire passing through each beam bunch twice during a single ''fly''. below they estimate the emittance growth induced by the interaction of the wires with the particles during these measurements. Changes of emittance from Flying Wire measurements conducted during three recent stores are compared with the estimations.

  17. The Lightning Electromagnetic Pulse Coupling Effect Inside the Shielding Enclosure With Penetrating Wire

    Science.gov (United States)

    Jiao, Xue; Yang, Bo

    2017-10-01

    To study the lightning electromagnetic pulse (LEMP) coupling and protection problems of shielding enclosure with penetrating wire, we adopt the model with proper size which is close to the practical engineering and the two-step finite-difference time-domain (FDTD) method is used for calculation in this paper. It is shown that the coupling voltage on the circuit lead inside the enclosure increases about 34 dB, when add 1.0 m long penetrating wire at the aperture, comparing with the case without penetrating wire. Meanwhile, the waveform, has the same wave outline as the lightning current source, shows that the penetrating wire brings a large number of low frequency component into the enclosure. The coupling effect in the enclosure will reduce greatly when penetrating wire has electrical connection with the enclosure at the aperture and the coupling voltage increase only about 12 dB than the case without penetrating wire. Moreover, the results show that though the waveguide pipe can reduce the coupling effect brought by the penetrating wire, the exposing part of penetrating wire can increase the coupling when the penetrating wire outside the enclosure is longer than the waveguide pipe and the longer the exposing part is, the stronger the coupling is.

  18. Plasma formation in metallic wire Z pinches

    Science.gov (United States)

    Chittenden; Lebedev; Ruiz-Camacho; Beg; Bland; Jennings; Bell; Haines; Pikuz; Shelkovenko; Hammer

    2000-04-01

    Plasma formation in metallic wire Z pinches is modeled using a two-dimensional resistive magnetohydrodynamics code. Modified Thomas-Fermi equations of state and dense plasma transport coefficients allow the phase transitions from solid to plasma to be approximated. Results indicate the persistence of a two-component structure with a cold, dense core embedded within a much hotter, low density, m=0 unstable corona. Extensive benchmark testing against data from a number of single-wire experiments is presented. Artificial laser schlieren and x-ray back-lighting images generated from the code data are compared directly to experimental results. The results were found to be insensitive to inaccuracies in the equations of state and transport coefficients. Simulations of individual wires in a wire array show different behavior to that observed experimentally due to the absence of three-dimensional effects. Simulations with similar conditions to wires in an array show a general trend in the plasma structure at start of implosion from discrete wires with large m=0 perturbation amplitudes to partially merged wires with smaller perturbation amplitudes as the number of wires is increased. Results for a wire number scan with aluminum wire arrays on the SATURN generator suggest that the observed sharp transition to high x-ray power at around 40 wires corresponds to a sharp decrease in m=0 perturbation amplitude and hence a sharp decrease in the seed perturbation for the Rayleigh-Taylor instability.

  19. Design and implementation of wire tension measurement system for MWPCs used in the STAR iTPC upgrade

    Science.gov (United States)

    Wang, Xu; Shen, Fuwang; Wang, Shuai; Feng, Cunfeng; Li, Changyu; Lu, Peng; Thomas, Jim; Xu, Qinghua; Zhu, Chengguang

    2017-07-01

    The STAR experiment at RHIC is planning to upgrade the Time Projection Chamber which lies at the heart of the detector. We have designed an instrument to measure the tension of the wires in the multi-wire proportional chambers (MWPCs) which will be used in the TPC upgrade. The wire tension measurement system causes the wires to vibrate and then it measures the fundamental frequency of the oscillation via a laser based optical platform. The platform can scan the entire wire plane, automatically, in a single run and obtain the wire tension on each wire with high precision. In this paper, the details about the measurement method and the system setup will be described. In addition, the test results for a prototype MWPC to be used in the STAR-iTPC upgrade will be presented.

  20. From wired to wireless: a miniature robot for intestinal inspection.

    Science.gov (United States)

    Chi, Dongxiang; Yan, Guozheng

    2003-01-01

    Increasingly more robots are used for various medical purposes, one of which is for intestinal inspection. A prototype robotic endoscope is presented along with a locomotion mechanism and relative experiment. Image, pH, pressure and temperature, etc. can be measured by the robot, which is very helpful in diagnoses. A wired robot will be replaced by a wireless robot because it is not comfortable for subjects and the wired robot cannot advance further into the small intestine because of too many folds and projections in the intestine. Key obstacles of the future wireless robot for intestinal inspection are discussed in detail and a reversed tracking method is provided.

  1. Synthesis of Commercial Products from Copper Wire-Drawing Waste

    Science.gov (United States)

    Ayala, J.; Fernández, B.

    2014-06-01

    Copper powder and copper sulfate pentahydrate were obtained from copper wire-drawing scale. The hydrometallurgical recycling process proposed in this article yields a high-purity copper powder and analytical grade copper sulfate pentahydrate. In the first stage of this process, the copper is dissolved in sulfuric acid media via dismutation of the scale. In the second stage, copper sulfate pentahydrate is precipitated using ethanol. Effects such as pH, reaction times, stirring speed, initial copper concentration, and ethanol/solution volume ratio were studied during the precipitation from solution reaction. The proposed method is technically straightforward and provides efficient recovery of Cu from wire-drawing scale.

  2. Slice of LHC dipole wiring

    CERN Multimedia

    Dipole model slice made in 1994 by Ansaldo. The high magnetic fields needed for guiding particles around the Large Hadron Collider (LHC) ring are created by passing 12’500 amps of current through coils of superconducting wiring. At very low temperatures, superconductors have no electrical resistance and therefore no power loss. The LHC is the largest superconducting installation ever built. The magnetic field must also be extremely uniform. This means the current flowing in the coils has to be very precisely controlled. Indeed, nowhere before has such precision been achieved at such high currents. 50’000 tonnes of steel sheets are used to make the magnet yokes that keep the wiring firmly in place. The yokes constitute approximately 80% of the accelerator's weight and, placed side by side, stretch over 20 km!

  3. Sintered wire cesium dispenser photocathode

    Science.gov (United States)

    Montgomery, Eric J; Ives, R. Lawrence; Falce, Louis R

    2014-03-04

    A photoelectric cathode has a work function lowering material such as cesium placed into an enclosure which couples a thermal energy from a heater to the work function lowering material. The enclosure directs the work function lowering material in vapor form through a low diffusion layer, through a free space layer, and through a uniform porosity layer, one side of which also forms a photoelectric cathode surface. The low diffusion layer may be formed from sintered powdered metal, such as tungsten, and the uniform porosity layer may be formed from wires which are sintered together to form pores between the wires which are continuous from the a back surface to a front surface which is also the photoelectric surface.

  4. CCD Photometry of bright stars using objective wire mesh

    Energy Technology Data Exchange (ETDEWEB)

    Kamiński, Krzysztof; Zgórz, Marika [Astronomical Observatory Institute, Faculty of Physics, A. Mickiewicz University, Słoneczna 36, 60-286 Poznań (Poland); Schwarzenberg-Czerny, Aleksander, E-mail: chrisk@amu.edu.pl [Copernicus Astronomical Centre, ul. Bartycka 18, PL 00-716 Warsaw (Poland)

    2014-06-01

    Obtaining accurate photometry of bright stars from the ground remains problematic due to the danger of overexposing the target and/or the lack of suitable nearby comparison stars. The century-old method of using objective wire mesh to produce multiple stellar images seems promising for the precise CCD photometry of such stars. Furthermore, our tests on β Cep and its comparison star, differing by 5 mag, are very encouraging. Using a CCD camera and a 20 cm telescope with the objective covered by a plastic wire mesh, in poor weather conditions, we obtained differential photometry with a precision of 4.5 mmag per two minute exposure. Our technique is flexible and may be tuned to cover a range as big as 6-8 mag. We discuss the possibility of installing a wire mesh directly in the filter wheel.

  5. A development of the method of the control signal formation for the hot plate mill automation systems to improve the flatness of the finish plate

    Directory of Open Access Journals (Sweden)

    Voronin Stanislav S.

    2016-01-01

    Full Text Available This article describes how to control of the hot plate mill automation system to improve the quality metrics if the final strip. Based on the data of the modern hot rolling mills the classification of the cage equipment was designed. Depending on the degree of influence on the magnitude of reduction, the equipment was divided into categories. The functioning of every system including the main and the vertical cages was described. The conditions of electrical and hydraulic mechanisms was marked. The developed algorithm allows to improve defects based on the finite number of the thickness measurements given by special non-contact sensors. The example of regulators signals calculating was shown. The result of the algorithm operating was illustrated.

  6. Ureteroscopy during pregnancy with follow-the-wire technique ...

    African Journals Online (AJOL)

    Purpose: To present our experience with ureteroscopy during pregnancy using the technique of following the wire ureteroscopically with no need for fluoroscopy. Patients and Methods: The study included 26 pregnant patients suffering from renal colic not responding to medication between March 2002 and January 2009.

  7. Inelastic scattering and local heating in atomic gold wires

    DEFF Research Database (Denmark)

    Frederiksen, Thomas; Brandbyge, Mads; Lorente, N.

    2004-01-01

    We present a method for including inelastic scattering in a first-principles density-functional computational scheme for molecular electronics. As an application, we study two geometries of four-atom gold wires corresponding to two different values of strain and present results for nonlinear...

  8. First Experimental Results And Improvements On Profile Measurements With The Vibrating Wire Scanner

    CERN Document Server

    Arutunian, S G; Dobrovolski, N M; Mailian, M R; Soghoyan, H E; Vasiniuk, I E

    2003-01-01

    The paper presents the first experimental results of transverse profile scans using a wire scanner based on a vibrating wire (vibrating wire scanner - VWS). The measurements were performed at the injector electron beam (6 nA) of the Yerevan synchrotron. The beam profile information is obtained by measuring the wire natural oscillations that depend on the wire temperature. This first experiments on weak electron beam proved this new method as a very sensitive tool, even suitable for tail measurements. Additional, improvements were tested to overcome some problems connected with signal conditioning and signal transfer in the presence of electromagnetic noise. As a result the noises were neatly separated and reduced. A mathematical method for rejection of distorted data was developed. Experiments with the scanner at the PETRA accelerator at DESY are planned for measurements of beam tails.

  9. Proportional counters aged anode wire recovering using an 80%CF4 + 20%CO2 gas mixture

    CERN Document Server

    Gavrilov, Gennady; Conti, Richard; Fetisov, Andrey; Maysuzenko, Dmitry; Shvecova, Natalia; Vakhtel, Victor

    2011-01-01

    A technique to recover a gas proportional counter having an aged anode wire using a glow discharge in an 80%CF4 + 20%CO2 gas mixture has been developed and tested. Studies of aging effects were carried out under sustained irradiation by an intense 90Sr -source of the straw proportional counters operated with a 60%Ar + 30%CO2 + 10%CF4 gas mixture. Special attention was paid to the aging mechanism of the anode wires. Our experience showed that using a given gas mixture the swelling of the anode wires is a typical mode of aging that leads to degradation of the gas gain. The proposed method of recovery provided a complete restoration of the gas gain and the signal amplitude in the damaged zone of the wire. SEM/XEM analysis confirmed successful cleaning WOx deposits from the wire surface. The application of this method to recover the aged gaseous detectors in real experimental conditions is discussed.

  10. Radiation and scattering by thin-wire structures in the complex frequency domain. [electromagnetic theory for thin-wire antennas

    Science.gov (United States)

    Richmond, J. H.

    1974-01-01

    Piecewise-sinusoidal expansion functions and Galerkin's method are employed to formulate a solution for an arbitrary thin-wire configuration in a homogeneous conducting medium. The analysis is performed in the real or complex frequency domain. In antenna problems, the solution determines the current distribution, impedance, radiation efficiency, gain and far-field patterns. In scattering problems, the solution determines the absorption cross section, scattering cross section and the polarization scattering matrix. The electromagnetic theory is presented for thin wires and the forward-scattering theorem is developed for an arbitrary target in a homogeneous conducting medium.

  11. A simple technique to retrieve broken guide wire transfixing hip joint

    Directory of Open Access Journals (Sweden)

    Daya Krishna

    2015-01-01

    Full Text Available While operating on the hip joint, breaking of guide wire became a challenge for treating orthopedic surgeon. Here we report a simple method of removal, which requires limited resources and does not need sophisticated instrumentation. By using this method, we remove broken guide wire in a patient of sub-trochantric fracture of femur managed by close reduction and internal fixation by proximal femoral nail. During the removal of the guide wire, after placing distal screw in the neck the guide wire comes out with some difficulty in the final view on image intensifier - the guide wire broken and transfixes the hip joint but does not enter the pelvis. After removal of the distal screw, its cannulated drill bit was connected to a T-handle and introduced into the track of distal screw up to the broken distal end of guide wire and slow manual reaming done under C-arm image intensifier to prevent damage to the articular cartilage. This process was repeated three times after cleaning drill bit each time to clear the base of guide wire for grasping its distal end. With the help of Kerryson rounger/grasper, the distal end of the guide wire was grasped and easily removed. The distal screw was placed in its original track and the procedure was completed.

  12. A Comparative Study of Bio Degradation of Various Orthodontic Arch Wires: An In Vitro Study

    Science.gov (United States)

    Gopikrishnan, S; Melath, Anil; Ajith, V V; Mathews, N Binoy

    2015-01-01

    Background: Orthodontic wires are the corner stones of the science and art of orthodontics and they remain in the patient’s mouth for a prolonged period of 18-24 months. It is but natural to expect that they will undergo some biodegradation when in the oral environment during that period. This study aims to compare the biodegradation characteristics of four different orthodontic wires, stainless steel, nickel titanium (NiTi), titanium molybdenum alloy (TMA), and copper NiTi and to assess whether these biodegradation products, are within acceptable limits. Materials and Methods: This study involved the incubation of four different wires in artificial saliva and analyzing the amount of metal released from them at the end of a 28 days study period. The metals analyzed for where nickel, chromium, copper, cobalt, manganese, iron, molybdenum, and titanium. The artificial saliva was changed on days 7, 14, and 21 to prevent the saturation of metals in the artificial saliva. At the end of 28 days, these four samples of artificial saliva of each wire were mixed together and analyzed for the eight metals using an inductively coupled plasma spectroscope. Results: The results showed only the release of nickel, chromium, and iron from stainless steel wire, nickel from NiTi wire, nickel, and chromium from copper NiTi and none from TMA wire. Conclusion: The metals released from arch wires are of such minute quantities to be of any biologic hazard. The amount of metals released is well within acceptable biocompatible limits. Though this study has analyzed the biodegradation of various orthodontic wires, orthodontic wires are never used alone in mechanotherapy. Orthodontic wires along with multiband appliance system with which it is always used and in combination with accessories like face bows may release more metals. PMID:25709360

  13. Release of metal ions from round and rectangular NiTi wires

    Directory of Open Access Journals (Sweden)

    Arash Azizi

    2016-04-01

    Full Text Available Abstract Background The aim of this study was to evaluate the amount of nickel and titanium ions released from two wires with different shapes and a similar surface area. Methods Forty round nickel-titanium (NiTi arch wires with the diameter of 0.020 in. and 40 rectangular NiTi arch wires with the diameter of 0.016 × 0.016 in. were immersed in artificial saliva during a 21-day period. The surface area of both wires was 0.44 in.2. Wires were separately dipped into polypropylene tubes containing 50 ml of buffer solution and were incubated and maintained at 37 °C. Inductively coupled plasma atomic emission spectrometry (ICP-AES was used to measure the amount of ions released after exposure lengths of 1 h, 24 h, 1 week, and 3 weeks. Repeated measures ANOVA and Tukey tests were used to evaluate the data. Results The results indicated that the amount of nickel and titanium concentrations was significantly higher in the rectangular wire group. The most significant release of all metals was measured after the first hour of immersion. In the rectangular wire group, 243 ± 4.2 ng/ml of nickel was released after 1 h, while 221.4 ± 1.7 ng/ml of nickel was released in the round wire group. Similarly, 243.3 ± 2.8 ng/ml of titanium was released in the rectangular wire group and a significantly lower amount of 211.9 ± 2.3 ng/ml of titanium was released in the round wire group. Conclusions Release of metal ions was influenced by the shape of the wire and increase of time.

  14. "Cut wires grating – single longitudinal wire" planar metastructure to achieve microwave magnetic resonance in a single wire

    Directory of Open Access Journals (Sweden)

    G. Kraftmakher

    2012-09-01

    Full Text Available Here we present metastructures containing cut-wire grating and a single longitudinal cut-wire orthogonal to grating’s wires. Experimental investigations at microwaves show these structures can provide strong magnetic resonant response of a single nonmagnetic cut-wire in dependence on configuration and sizes in the case when metastructures are oriented along the direction of wave propagation and cut-wires of grating are parallel to the electric field of a plane electromagnetic wave. It is suggested a concept of magnetic response based on antiparallel resonant currents excited by magnetic field of surface polaritons in many spatial LC-circuits created from cut-wire pairs of a grating and section of longitudinal cut-wire. Three separately observed resonant effects connected with grating, LC-circuits and with longitudinal cut-wire have been identified applying measurements in waveguides, cutoff waveguides and free space. To tune and mark resonance split cut-wires are loaded with varactor diodes.

  15. Electromagnetic Behaviour of Metallic Wire Structures

    CERN Document Server

    Chui, S T

    2013-01-01

    Despite the recent development and interest in the photonics of metallic wire structures, the relatively simple concepts and physics often remain obscured or poorly explained to those who do not specialize in the field. Electromagnetic Behaviour of Metallic Wire Structures provides a clear and coherent guide to understanding these phenomena without excessive numerical calculations.   Including both background material and detailed derivations of the various different formulae applied, Electromagnetic Behaviour of Metallic Wire Structures describes how to extend basic circuit theory relating to voltages, currents, and resistances of metallic wire networks to include situations where the currents are no longer spatially uniform along the wire. This lays a foundation for a deeper understanding of the many new phenomena observed in meta-electromagnetic materials.   Examples of applications are included to support this new approach making Electromagnetic Behaviour of Metallic Wire Structures a comprehensive and ...

  16. Hot-pressed geopolymer

    DEFF Research Database (Denmark)

    Ranjbar, Navid; Mehrali, Mohammad; Maheri, Mahmoud R.

    2017-01-01

    /FA, duration of hot-pressing and sodium concentration are studied. Together with detailed experimental studies, our results reveal that the most dominant factor is the induced pressure. The main results indicated that the highest compressive strength of the geopolymer (134 MPa) could be obtained by employing...... the hot pressing, temperature and duration of 41.4 MPa, 350 °C and 20 min, respectively. The microstructure of the hot-pressed specimens showed more developed geopolymer matrix compared with conventional ones leading to higher compressive strength in much shortest time. The improved mechanical properties...

  17. IEE wiring regulations explained and illustrated

    CERN Document Server

    Scaddan, Brian

    2013-01-01

    The IEE Wiring Regulations Explained and Illustrated, Second Edition discusses the recommendations of the IEE Regulations for the Electrical Equipment of Buildings for the safe selection or erection of wiring installations. The book emphasizes earthing, bonding, protection, and circuit design of electrical wirings. The text reviews the fundamental requirements for safety, earthing systems, the earth fault loop impedance, and supplementary bonding. The book also describes the different types of protection, such as protection against mechanical damage, overcurrent, under voltage (which prevents

  18. Radiofrequency Wire Recanalization of Chronically Thrombosed TIPS

    Energy Technology Data Exchange (ETDEWEB)

    Majdalany, Bill S., E-mail: bmajdala@med.umich.edu [University of Michigan Health System, Division of Interventional Radiology, Department of Radiology (United States); Elliott, Eric D., E-mail: eric.elliott@osumc.edu [The Ohio State University Wexner Medical Center, Division of Interventional Radiology, Department of Radiology (United States); Michaels, Anthony J., E-mail: Anthony.michaels@osumc.edu; Hanje, A. James, E-mail: James.Hanje@osumc.edu [The Ohio State University Wexner Medical Center, Division of Gastroenterology and Hepatology, Department of Medicine (United States); Saad, Wael E. A., E-mail: wsaad@med.umich.edu [University of Michigan Health System, Division of Interventional Radiology, Department of Radiology (United States)

    2016-07-15

    Radiofrequency (RF) guide wires have been applied to cardiac interventions, recanalization of central venous thromboses, and to cross biliary occlusions. Herein, the use of a RF wire technique to revise chronically occluded transjugular intrahepatic portosystemic shunts (TIPS) is described. In both cases, conventional TIPS revision techniques failed to revise the chronically thrombosed TIPS. RF wire recanalization was successfully performed through each of the chronically thrombosed TIPS, demonstrating initial safety and feasibility in this application.

  19. NEW DIRECTIONS IN THE ROLLED WIRE DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    A. V. Vedeneev

    2004-01-01

    Full Text Available Analysis of the world practice and comparison with the competitors data shows, that for keeping up of RUP “BMZ'' competitiveness it is necessary to carry out works in directions of perfection of the steel wire cord production technology, development of steel wire cord, development of the breaker constructions with the high infiltration of rubber of wire with superstandard diameter and etc.

  20. Experimental setup to detect superconducting wire motion

    OpenAIRE

    K. Ruwali; A. Yamanaka; Y. Teramoto; K. Nakanishi; K. Hosoyama

    2009-01-01

    An experimental setup was designed and fabricated to study superconducting wire motion under the influence of electromagnetic force. Experiments were conducted at 4.2 K by varying the experimental conditions such as the tension to the superconducting wire and different insulating materials at the interface of the superconducting wire and head part. The insulating materials used in the experiments were polyimide film and a high strength polyethylene fiber cloth, Dyneema. Details of the experim...

  1. Minimisation of the wire position uncertainties of the new CERN vacuum wire scanner

    CERN Document Server

    AUTHOR|(CDS)2069346; Barjau Condomines, A

    In the next years the luminosity of the LHC will be significantly increased. This will require a much higher accuracy of beam profile measurement than actually achievable by the current wire scanner. The new fast wire scanner is foreseen to measure small emittance beams throughout the LHC injector chain, which demands a wire travelling speed up to 20 ms-1 and position measurement accuracy of the order of a few microns. The vibrations of the mechanical parts of the system, and particularly the vibrations of the thin carbon wire, were identified as the major error sources of wire position uncertainty. Therefore the understanding of the wire vibrations is a high priority for the design and operation of the new device. This document presents the work performed to understand the main causes of the wire vibrations observed in one of the existing wire scanner and the new proposed design.

  2. Controlled motion of domain walls in submicron amorphous wires

    Directory of Open Access Journals (Sweden)

    Mihai Ţibu

    2016-05-01

    Full Text Available Results on the control of the domain wall displacement in cylindrical Fe77.5Si7.5B15 amorphous glass-coated submicron wires prepared by rapid quenching from the melt are reported. The control methods have relied on conical notches with various depths, up to a few tens of nm, made in the glass coating and in the metallic nucleus using a focused ion beam (FIB system, and on the use of small nucleation coils at one of the sample ends in order to apply magnetic field pulses aimed to enhance the nucleation of reverse domains. The notch-based method is used for the first time in the case of cylindrical ultrathin wires. The results show that the most efficient technique of controlling the domain wall motion in this type of samples is the simultaneous use of notches and nucleation coils. Their effect depends on wire diameter, notch depth, its position on the wire length, and characteristics of the applied pulse.

  3. Controlled motion of domain walls in submicron amorphous wires

    Energy Technology Data Exchange (ETDEWEB)

    Ţibu, Mihai; Lostun, Mihaela; Rotărescu, Cristian; Atiţoaie, Alexandru; Lupu, Nicoleta; Óvári, Tibor-Adrian, E-mail: taovari@phys-iasi.ro; Chiriac, Horia [Department of Magnetic Materials and Devices, National Institute of Research and Development for Technical Physics, Iaşi, 700050 (Romania); Allwood, Dan A. [Department of Materials Science and Engineering, University of Sheffield, Sheffield, S1 3JD (United Kingdom)

    2016-05-15

    Results on the control of the domain wall displacement in cylindrical Fe{sub 77.5}Si{sub 7.5}B{sub 15} amorphous glass-coated submicron wires prepared by rapid quenching from the melt are reported. The control methods have relied on conical notches with various depths, up to a few tens of nm, made in the glass coating and in the metallic nucleus using a focused ion beam (FIB) system, and on the use of small nucleation coils at one of the sample ends in order to apply magnetic field pulses aimed to enhance the nucleation of reverse domains. The notch-based method is used for the first time in the case of cylindrical ultrathin wires. The results show that the most efficient technique of controlling the domain wall motion in this type of samples is the simultaneous use of notches and nucleation coils. Their effect depends on wire diameter, notch depth, its position on the wire length, and characteristics of the applied pulse.

  4. Wire system aging assessment and condition monitoring (WASCO)

    Energy Technology Data Exchange (ETDEWEB)

    Fantoni, P.F. [Institutt for energiteknikk (Norway); Nordlund, A. [Chalmers Univ. of Technology (Sweden)

    2006-04-15

    Nuclear facilities rely on electrical wire systems to perform a variety of functions for successful operation. Many of these functions directly support the safe operation of the facility; therefore, the continued reliability of wire systems, even as they age, is critical. Condition Monitoring (CM) of installed wire systems is an important part of any aging program, both during the first 40 years of the qualified life and even more in anticipation of the license renewal for a nuclear power plant. This report describes a method for wire system condition monitoring, developed at the Halden Reactor Project, which is based on Frequency Domain Reflectometry. This method resulted in the development of a system called LIRA (LIne Resonance Analysis), which can be used on-line to detect any local or global changes in the cable electrical parameters as a consequence of insulation faults or degradation. LIRA is composed of a signal generator, a signal analyser and a simulator that can be used to simulate several failure/degradation scenarios and assess the accuracy and sensitivity of the LIRA system. Chapter 5 of this report describes an complementary approach based on positron measurement techniques, used widely in defect physics due to the high sensitivity to micro defects, in particular open volume defects. This report describes in details these methodologies, the results of field experiments and the proposed future work. (au)

  5. Friction between different wire bracket combinations in artificial saliva – an in vitro evaluation

    Science.gov (United States)

    FIDALGO, Tatiana Kelly da Silva; PITHON, Matheus Melo; MACIEL, José Vinicius Bolognesi; BOLOGNESE, Ana Maria

    2011-01-01

    Objective The objective this work was to assess the friction coefficient between brackets and wires of different materials under conditions simulating the oral environment. Material and Methods Stainless steel (SS) and titanium-molybdenum alloy (TMA) wires of 0.019x0.025-in diameter (American Orthodontics) and polycarbonate bracket (American Orthodontics), ceramic bracket (American Orthodontics), and metal bracket (3M Unitek) with slots of 0.022x0.030-in were used. The friction coefficient was assessed by means of mechanical traction with the system immersed in artificial saliva. The mean roughness of both wire surface and bracket slots was evaluated by using a surface profilometer. Results The system using TMA wire and polycarbonate bracket had the highest roughness (p<0.05). SS wire with ceramic bracket had the highest friction coefficient, whereas the use of metallic bracket yielded the lowest (p<0.05). However, it was observed a statistically significant difference in the system using TMA wire and ceramic bracket compared to that using TMA wire and polycarbonate bracket (p=0.038). Conclusion Ceramic brackets in association with SS wire should be judiciously used, since this system showed a high friction coefficient. PMID:21437471

  6. Repair of olecranon fractures using fiberWire without metallic implants: report of two cases

    Directory of Open Access Journals (Sweden)

    Okawa Atsushi

    2010-10-01

    Full Text Available Abstract Olecranon fractures are a common injury in fractures. The tension band technique for olecranon fractures yields good clinical outcomes; however, it is associated with significant complications. In many patients, implants irritate overlying soft tissues and cause pain. This is mostly due to protrusion of the proximal ends of the K-wires or by the twisted knots of the metal wire tension band. Below we described 2 cases of olecranon fractures treated with a unique technique using FiberWire without any metallic implants. Technically, the fragment was reduced, and two K-wires were inserted from the dorsal cortex of the distal segment to the tip of the olecranon. K-wire was exchanged for a suture retriever, and 2 strands of FiberWire were retrieved twice. Each of the two FiberWires was manually tensioned and knotted on the posterior surface of the olecranon. Bony unions could be achieved, and patients had no complaint of pain and skin irritation. There was only a small loss of flexion and extension in comparison with that of the contralateral side, and the patient did not feel inconvenienced in his daily life. Using the method described, difficulty due to K-wire or other metallic implants was avoided.

  7. Application of the Wire Bonding Technology to a Flexible Neural Probe

    Science.gov (United States)

    Shimizu, Koichi; Nakanishi, Motofumi; Makikawa, Masaaki; Asajima, Syuzo; Konishi, Satoshi

    This paper proposes a novel neural probe using flexible metal wire for wire bonding on LSI chip. Wire bonding technology can provide a number of flexible wire arrays. The proposed neural probe is used for a nerve interface for functional electric stimulation (FES) technology which assists the paralysis of living body function by a spinal cord injury. The flexibility of probe will provide low invasive and safe neural interfaces for the nerve tissue from a long term view. We employ a combination of wire bonding and laser machining for the fabrication of aligned flexible probes. Aligned bonded flexible metal wires on electrodes are converted to probe arrays by cutting the bridge between electrodes. Typical dimension of a bonding wire is several tens μm in diameter and is suitable for neural probe to be inserted into nerve bundles. Needle shape is formed by electro-polishing of cut edge. Proposed method can be benefited by advantages of wire bonding as the widespread technology in electronics industry. Developed flexible neural probe based on the proposed technology is estimated as a nerve interface by inserting to a sciatic nerve of a rat.

  8. Relationship between friction force and orthodontic force at the leveling stage using a coated wire

    Directory of Open Access Journals (Sweden)

    Masaki MURAYAMA

    2013-12-01

    Full Text Available The relationship between orthodontic force and friction produced from an archwire and brackets affects the sliding of the wire in the leveling stage. Objective: The purpose of this study was to evaluate the relationship between force and friction in a small esthetic nickel-titanium (Ni-Ti wire. Material and Methods: Five esthetic wires (three coated and two plated and two small, plain Ni-Ti wires (0.012 and 0.014 inches were used. We performed a three-point bending test according to ISO 15841 and the drawing test with a dental arch model designed with upper linguoversion of the lateral incisor in the arch (displacements of 0.5, 1.0, 2.0 and 3.0 mm, and evaluated the relationship between them. Results: Unloading bending forces of all wires at displacements of less than 1.0 mm were larger than friction forces, but all friction forces at displacements exceeding 2.0 mm were larger than unloading bending forces. The arch likely expands when displacement from the proximal brackets exceeds 1.0 mm. The friction force of a martensite 0.014-inch Ni-Ti wire was significantly greater than those of the other esthetic and austenitic wires. Conclusions: A wire with the smallest possible friction force should be used in cases with more than 1.0 mm displacement.

  9. Development of (Nb,Ta3Sn multifilamentary superconductor wire for high current applications

    Directory of Open Access Journals (Sweden)

    Durval Rodrigues Jr.

    2000-10-01

    Full Text Available The optimization of the energy generated by a MagnetoHydroDynamic (MHD channel using a superconducting magnet demands the optimization of the magnetic field of the system and of the critical points on the magnet winding. This work must include the development of a high performance superconductor wire suitable for this system. Aiming to the construction of improved performance MHD channel, it was developed a low cost superconductor wire, with the required characteristics. The wire was made using a technology compatible with the assembling steps and heat treatment conditions of the MHD superconducting magnets fabrication. It was used the internal Sn method in Nb-7.5wt%Ta tube to fabricate a 271-filament wire with a diameter of 0.81 mm and a Cu/nonCu ratio of 2.3. The wire was heat treated at 200 °C to diffuse the Sn into the Cu shell, producing bronze, followed by the final reaction at temperatures ranging from 670 °C to 730 °C during 25 to 150 h, to produce (Nb,Ta3Sn. The superconducting wire characterization was made measuring the critical current Ic versus the applied magnetic field in the range of 5 to 20 T, the critical temperature Tc and the residual resistivity ratio (RRR. The wire transported critical currents above those available in commercial superconducting wires. These values of Ic are higher than the expected values for the optimization of the MHD channel.

  10. Aircraft Wiring Support Equipment Integration Laboratory (AWSEIL)

    Data.gov (United States)

    Federal Laboratory Consortium — Purpose:The Aircraft Wiring Support Equipment Integration Laboratory (AWSEIL) provides a variety of research, design engineering and prototype fabrication services...

  11. submitter Dynamical Models of a Wire Scanner

    CERN Document Server

    Barjau, Ana; Dehning, Bernd

    2016-01-01

    The accuracy of the beam profile measurements achievable by the current wire scanners at CERN is limited by the vibrations of their mechanical parts. In particular, the vibrations of the carbon wire represent the major source of wire position uncertainty which limits the beam profile measurement accuracy. In the coming years, due to the Large Hadron Collider (LHC) luminosity upgrade, a wire traveling speed up to 20 $m s^{−1}$ and a position measurement accuracy of the order of 1 μm will be required. A new wire scanner design based on the understanding of the wire vibration origin is therefore needed. We present the models developed to understand the main causes of the wire vibrations observed in an existing wire scanner. The development and tuning of those models are based on measurements and tests performed on that CERN proton synchrotron (PS) scanner. The final model for the (wire + fork) system has six degrees-of-freedom (DOF). The wire equations contain three different excitation terms: inertia...

  12. Preparation, microstructure and degradation performance of biomedical magnesium alloy fine wires

    Directory of Open Access Journals (Sweden)

    Jing Bai

    2014-10-01

    Full Text Available With the development of new biodegradable Mg alloy implant devices, the potential applications of biomedical Mg alloy fine wires are realized and explored gradually. In this study, we prepared three kinds of Mg alloy fine wires containing 4 wt% RE(Gd/Y/Nd and 0.4 wt% Zn with the diameter less than 0.4 μm through casting, hot extruding and multi-pass cold drawing combined with intermediated annealing process. Their microstructures, mechanical and degradation properties were investigated. In comparison with the corresponding as-extruded alloy, the final fine wire has significantly refined grain with an average size of 3–4 μm, and meanwhile shows higher yield strength but lower ductility at room temperature. The degradation tests results and surface morphologies observations indicate that Mg–4Gd–0.4Zn and Mg–4Nd–0.4Zn fine wires have similar good corrosion resistance and the uniform corrosion behavior in SBF solution. By contrast, Mg–4Y–0.4Zn fine wire shows a poor corrosion resistance and the pitting corrosion behavior.

  13. China's 'Hot Money' Problems

    National Research Council Canada - National Science Library

    Martin, Michael F; Morrison, Wayne M

    2008-01-01

    .... The recent large inflow of financial capital into China, commonly referred to as "hot money," has led some economists to warn that such flows may have a destabilizing effect on China's economy...

  14. Hot Weather Tips

    Science.gov (United States)

    ... hot, heavy meals and don’t use the oven. Monitor medications: Find out if the person’s medications ... nia.nih.gov Photo: By High Contrast (Own work) [CC BY 3.0 de ( http://creativecommons.org/ ...

  15. FE modeling of Cu wire bond process and reliability

    NARCIS (Netherlands)

    Yuan, C.A.; Weltevreden, E.R.; Akker, P. van den; Kregting, R.; Vreugd, J. de; Zhang, G.Q.

    2011-01-01

    Copper based wire bonding technology is widely accepted by electronic packaging industry due to the world-wide cost reduction actions (compared to gold wire bond). However, the mechanical characterization of copper wire differs from the gold wire; hence the new wire bond process setting and new bond

  16. Hot Spot Cosmic Accelerators

    Science.gov (United States)

    2002-11-01

    The Universe is a violent place - as astronomers use increasingly sensitive means and methods to study the diverse processes out there, they become aware of the extraordinary forces acting in the space that surrounds us. With larger telescopes and ever-more sophisticated instruments, new information is gained about remote celestial objects and their behaviour. Among the most intriguing ones are the radio galaxies which emit prodiguous amounts of energy, in the form of fast-moving particles and intense electromagnetic radiation. One of these is known as 3C 445 ; it is located near the celestial equator within the zodiacal constellation Aquarius (The Waterman), at a distance of about 1 billion light-years. It most probably harbours a black hole at its centre, more massive than the one at the centre of our own galaxy, the Milky Way ( ESO PR 19/02 ). This galaxy was first observed from Cambridge (United Kingdom) in the 1950's and was listed as radio source no. 445 in the Third Cambridge Catalogue (1959), hence the name. Later observations revealed a strong outflow from this galaxy's active centre, visible on radio maps as two opposite plasma jets with strong synchrotron radiation ( [2]) originating from rapidly moving electrons in the associated magnetic field (image "a" in PR Photo 26/02 ). Now, a trio of European astronomers [1] have used two advanced instruments, ISAAC and FORS1 on the 8.2-m VLT ANTU telescope at the ESO Paranal Observatory (Chile) to obtain near-infrared images of these jets (images "b" and "c" in PR Photo 26/02 ). As can be clearly seen on the radio picture of 3C 445 obtained with the NRAO Very Large Array (VLA) radio facility ("a"), the plasma jets of fast particles emanating from the galaxy ram into the surrounding intergalactic medium (mostly primordial hydrogen), thereby producing two "shocks" , both at a distance of approximately 1.5 million light-years from the central galaxy and with particularly strong synchrotron emission. With a total

  17. Measurements of Flow Mixing at Subchannels in a Wire-Wrapped 61-Rod Bundle for a Sodium Cooled Fast Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dong Won; Kim, Hyungmo; Ko, Yung Joo; Choi, Hae Seob; Euh, Dong-Jin; Jeong, Ji-Young; Lee, Hyeong-Yeon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    For a safety analysis in a core thermal design of a sodium-cooled fast reactor (SFR), flow mixing characteristics at subchannels in a wire-wrapped rod bundle are crucial factor for the design code verification and validation. Wrapped wires make a cross flow in a circumference of the fuel rod, and this effect lets flow be mixed. Therefore the sub-channel analysis method is commonly used for thermal hydraulic analysis of a SFR, a wire wrapped sub-channel type. To measure flow mixing characteristics, a wire mesh sensing technique can be useful method. A wire mesh sensor has been traditionally used to measure the void fraction of a two-phase flow field, i.e. gas and liquid. However, the recent reports that the wire mesh sensor can be used successfully to recognize the flow field in liquid phase by injecting a tracing liquid with a different level of electric conductivity. The subchannel flow characteristics analysis method is commonly used for the thermal hydraulic analysis of a SFR, a wire wrapped subchannel type. In this study, mixing experiments were conducted successfully at a hexagonally arrayed 61-pin wire-wrapped fuel rod bundle test section. Wire mesh sensor was used to measure flow mixing characteristics. The developed post-processing method has its own merits, and flow mixing results were reasonable.

  18. THERMO-MECHANICALLY PROCESSED ROLLED WIRE FOR HIGH-STRENGTH ON-BOARD WIRE

    Directory of Open Access Journals (Sweden)

    V. A. Lutsenko

    2011-01-01

    Full Text Available It is shown that at twisting of wire of diameter 1,83 mm, produced by direct wire drawing of thermomechanically processed rolled wire of diameter 5,5 mm of steel 90, metal stratification is completely eliminated at decrease of carbon, manganese and an additional alloying of chrome.

  19. Finite element analysis on the wire breaking rule of 1×7IWS steel wire rope

    Directory of Open Access Journals (Sweden)

    Wenzheng Du

    2017-01-01

    Full Text Available Taking the wire rope of 1×7+IWS structure as the research object, the influences of the number of broken wires on the stress distribution under the same axial load were simulated and analysed, and it also explored the rule of wire breaking of steel wire ropes. Based on the SolidWorks software, the three-dimensional model of the wire rope was established. Importing the model into the ABAQUS, the finite element model of the steel wire rope was established. Firstly 5000 N axial tension was placed on the rope, the stress distribution was simulated and analysed, and the steel wire with the largest stress distribution was found out. Then one steel wire was truncated with the load unchanged, and the finite element simulation was carried out again, and repeated the steps several times. The results show that, with the increase of the number of broken wires, the Von-Mises stress of the wire rope increases sharply, and the stress distribution is concentrated on the rest of the unbroken wires, which brings great challenges to the safety of the wire rope.

  20. APPLICATION OF THE X-RAY STRUCTURE ANALYSIS FOR IMPROVEMENT OF TECHNOLOGICAL PROCES- SES OF WIRE PRODUCTION AT BMZ

    Directory of Open Access Journals (Sweden)

    D. V. Kuznetsov

    2012-01-01

    Full Text Available The X-ray diffraction methods of qualitative and quantative analysis of phase composition of the brass coating, scale on the surface of brass wire, rod, patented wire, methods of determining the characteristics of the microstrains the lattice ferritic matrix pearlitic high-carbon steel, are explored.