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Sample records for based hot plate

  1. Expression of the difference between the Cold (Han) and Hot (Re) natures of traditional Chinese medicines (Strobal and Rhubarb) based on the cold/hot plate differentiating assay.

    PubMed

    Zhao, HaiPing; Zhao, YanLing; Wang, JiaBo; Li, HanBing; Ren, YongShen; Zhou, CanPing; Yan, Dan; Xiao, XiaoHe

    2009-12-01

    In this study, objective differences between the Cold (Han) and Hot (Re) nature of traditional Chinese medicines, e.g. Strobal and Rhubarb, are determined by using a cold/hot plate differentiation technology. A novel, self-designed cold/hot plate differentiating instrument, with methodological study, was used to investigate the intervention of Strobal and Rhubarb on the temperature tropism of mice. Compared with the ICR and BALB/c mice, it was found that KM mice on the cold/hot plate were more sensitive to the change of temperature, within the tolerant temperature range of 15-40 degrees C. The temperature tropism behavior of mice is influenced by treatment with Rhubarb and Strobal, as is the activity of ATPase in liver tissue. These trends are consistent with the definition of the Cold/Hot nature of Chinese medicines based on traditional Chinese medicinal theory. This study showed that the differences of the Cold/Hot nature of traditional Chinese medicines. might be objectively represented by the temperature tropism of animal by means of cold/hot differentiating assay.

  2. High thermal capacity cold plate/hot plate

    NASA Technical Reports Server (NTRS)

    Hwangbo, H.; Mcever, W. S.

    1985-01-01

    The results of an analytical study to determine the feasibility of a novel two-phase cold plate/hot plate (CPHP) are presented. A key feature of the CPHP is the use of capillary forces to separate the liquid and vapor phases and distribute the liquid over the evaporating/condensing surface. The liquid phase is held by capillary forces in a reservoir and is carried to the evaporating surface by a wick. The reservoir is replenished at intervals from a valved external liquid supply line. In the hot plate mode, liquid accumulates in the reservoir and is removed by an external condensate line. Performance requirements for the device were capability of handling a power density of 4 watts/sq cm, an outlet quality (percentage of vapor flow to total flow) greater than 90 percent, and operation in a 0-g environment. An analytical model of CPHP operation was developed which concentrated on the liquid and vapor flows. It was found that the liquid carrying capillary grooves of rectangular cross-section gave significantly better predicted performance than V-shaped grooves. Using the analytical model, capillary groove width and length, vapor channel dimensions, and other parameters were selected to meet the performance requirements with a 100-percent margin.

  3. Effect of a hot spot on the strain response of an acoustically-loaded flat plate

    SciTech Connect

    Koval, L.R.; Jong, C.P.

    1989-01-01

    Previous studies of the acoustic fatigue of heated plates have treated uniformly-heated plates. The current study examines the effect of a 'hot spot' on the acoustic fatigue of a simply-supported flat plate. The hot spot is provided by a concentration of hot gas and is 'applied' to the plate through a convection boundary condition on the upper surface of the plate. For simplicity, the hot spot is assumed to be rectangular with its sides parallel to the sides of the plate. The size of the hot spot, the location of the hot spot, and the temperature of the hot spot were all varied to see their effects. 18 references.

  4. Graphene-Based "Hot Plate" for the Capture and Destruction of the Herpes Simplex Virus Type 1.

    PubMed

    Deokar, Archana R; Nagvenkar, Anjani P; Kalt, Inna; Shani, Lior; Yeshurun, Yosef; Gedanken, Aharon; Sarid, Ronit

    2017-02-16

    The study of graphene-based antivirals is still at a nascent stage and the photothermal antiviral properties of graphene have yet to be studied. Here, we design and synthesize sulfonated magnetic nanoparticles functionalized with reduced graphene oxide (SMRGO) to capture and photothermally destroy herpes simplex virus type 1 (HSV-1). Graphene sheets were uniformly anchored with spherical magnetic nanoparticles (MNPs) of varying size between ∼5 and 25 nm. Fourier-transform infrared spectroscopy (FT-IR) confirmed the sulfonation and anchoring of MNPs on the graphene sheets. Upon irradiation of the composite with near-infrared light (NIR, 808 nm, 7 min), SMRGO (100 ppm) demonstrated superior (∼99.99%) photothermal antiviral activity. This was probably due to the capture efficiency, unique sheet-like structure, high surface area, and excellent photothermal properties of graphene. In addition, electrostatic interactions of MNPs with viral particles appear to play a vital role in the inhibition of viral infection. These results suggest that graphene composites may help to combat viral infections including, but not only, HSV-1.

  5. Development of ion-plated aluminide diffusion coatings for thermal cyclic oxidation and hot corrosion protection of a nickel-based superalloy and a stainless steel

    NASA Astrophysics Data System (ADS)

    Elsawy, Abdel Raouf

    This project was carried out at the University of Toronto and Cametoid Ltd of Whitby, Ontario. Ohno continuous casting; a novel net shape casting technique, was used to generate, Al-Y, Al-Ce, Al-La, and Al-Si-Y, in form of 1.6 to 1.7 mm diameter alloy wires. These alloy wires exhibited suitable properties for use as feed materials to an Ion Vapor Deposition facility. The deposition parameters were optimized to provide coatings with a compact and cohesive columnar structure with reduced porosity and diffusion barriers that were essential to ensure the success of the diffusion process in the subsequent stage. Solid-state diffusion heat treatment processes were developed in order to form the stable aluminide phases, AlNi and FeAl, on IN738 and S310 substrates, respectively. Experiments simulating the coating service conditions and environments encountered during the prospective aerospace and fuel cell applications were conducted to evaluate the performance of each aluminide coating developed during this study. Thermal cyclic oxidation and molten sulfate corrosion studies were performed on coated IN738 pins at 1050°C and 900°C, respectively, simulating the service environment of turbine engine blades and other hot section components. Molten carbonate corrosion behavior was investigated for coated S310 coupons that were immersed in, or covered with a thin film of molten carbonate, at 650°C, in air plus 30%CO2, to simulate the operating conditions of the cathode-side separator plates of molten carbonate fuel cells. The behavior of the reactive elements, yttrium, cerium, lanthanum, and silicon in enhancing the adhesion of the protective aluminum oxide scale was determined by weight variation experiments, structural examination and compositional analysis. The influence of the base material elements, nickel, chromium, and iron, on the formation of protective oxides was investigated. All coatings were found to provide significant improvement for thermal cyclic oxidation

  6. Parallel-Plate Acoustic Absorbers For Hot Environments

    NASA Technical Reports Server (NTRS)

    Doychak, Joseph; Parrot, Tony L.

    1995-01-01

    Stacking patterns and materials chosen to suppress noise. Acoustic liners incorporating parallel-plate absorbing elements proposed for use in suppressing broadband aerodynamic noise originating in flows of hot gases in ducts. One potential application lies in suppressing noise generated in exhaust-jet mixer/ejectors in propulsion system of proposed High-Speed Civil Transport. In addition, such absorbers useful in any situation in which high temperature limits use of such conventional resonant acoustic-liner materials as perforated face sheets bonded to honey-comb-core panels.

  7. A passive guard for low thermal conductivity measurement of small samples by the hot plate method

    NASA Astrophysics Data System (ADS)

    Jannot, Yves; Degiovanni, Alain; Grigorova-Moutiers, Veneta; Godefroy, Justine

    2017-01-01

    Hot plate methods under steady state conditions are based on a 1D model to estimate the thermal conductivity, using measurements of the temperatures T 0 and T 1 of the two sides of the sample and of the heat flux crossing it. To be consistent with the hypothesis of the 1D heat flux, either a hot plate guarded apparatus is used, or the temperature is measured at the centre of the sample. On one hand the latter method can be used only if the ratio thickness/width of the sample is sufficiently low and on the other hand the guarded hot plate method requires large width samples (typical cross section of 0.6  ×  0.6 m2). That is why both methods cannot be used for low width samples. The method presented in this paper is based on an optimal choice of the temperatures T 0 and T 1 compared to the ambient temperature T a, enabling the estimation of the thermal conductivity with a centered hot plate method, by applying the 1D heat flux model. It will be shown that these optimal values do not depend on the size or on the thermal conductivity of samples (in the range 0.015-0.2 W m-1 K-1), but only on T a. The experimental results obtained validate the method for several reference samples for values of the ratio thickness/width up to 0.3, thus enabling the measurement of the thermal conductivity of samples having a small cross-section, down to 0.045  ×  0.045 m2.

  8. Low-Cost Magnetic Stirrer from Recycled Computer Parts with Optional Hot Plate

    ERIC Educational Resources Information Center

    Guidote, Armando M., Jr.; Pacot, Giselle Mae M.; Cabacungan, Paul M.

    2015-01-01

    Magnetic stirrers and hot plates are key components of science laboratories. However, these are not readily available in many developing countries due to their high cost. This article describes the design of a low-cost magnetic stirrer with hot plate from recycled materials. Some of the materials used are neodymium magnets and CPU fans from…

  9. Experimental comparison and validation of hot-ball method with guarded hot plate method on polyurethane foams

    NASA Astrophysics Data System (ADS)

    Hudec, Ján; Glorieux, Christ; Dieška, Peter; Kubičár, Ľudovít

    2016-07-01

    The Hot-ball method is an innovative transient method for measuring thermophysical properties. The principle is based on heating of a small ball, incorporated in measured medium, by constant heating power and simultaneous measuring of the ball's temperature response since the heating was initiated. The shape of the temperature response depends on thermophysical properties of the medium, where the sensor is placed. This method is patented by Institute of Physics, SAS, where the method and sensors based on this method are being developed. At the beginning of the development of sensors for this method we were oriented on monitoring applications, where relative precision is much more important than accuracy. Meanwhile, the quality of sensors was improved good enough to be used for a new application - absolute measuring of thermophysical parameters of low thermally conductive materials. This paper describes experimental verification and validation of measurement by hot-ball method. Thanks to cooperation with Laboratory of Soft Matter and Biophysics of Catholic University of Leuven in Belgium, established Guarded Hot Plate method was used as a reference. Details about measuring setups, description of the experiments and results of the comparison are presented.

  10. Thermal response simulation for tuning PID controllers in a 1016 mm guarded hot plate apparatus.

    PubMed

    Thomas, William C; Zarr, Robert R

    2011-07-01

    A mathematical model has been developed and used to simulate the controlled thermal performance of a large guarded hot-plate apparatus. This highly specialized apparatus comprises three interdependent components whose temperatures are closely controlled in order to measure the thermal conductivity of insulation materials. The simulation model was used to investigate control strategies and derive controller gain parameters that are directly transferable to the actual instrument. The simulations take orders-of-magnitude less time to carry out when compared to traditional tuning methods based on operating the actual apparatus. The control system consists primarily of a PC-based PID control algorithm that regulates the output voltage of programmable power amplifiers. Feedback parameters in the form of controller gains are required for the three heating circuits. An objective is to determine an improved set of gains that meet temperature control criteria for testing insulation materials of interest. The analytical model is based on aggregated thermal capacity representations of the primary components and includes the same control algorithm as used in the actual hot-plate apparatus. The model, accounting for both thermal characteristics and temperature control, was validated by comparisons with test data. The tuning methodology used with the simulation model is described and results are presented. The resulting control algorithm and gain parameters have been used in the actual apparatus without modification during several years of testing materials over wide ranges of thermal conductivity, thickness, and insulation resistance values.

  11. Effects of the microstructure of twin roll cast and hot rolled plates on the surface quality of presensitized plates

    NASA Astrophysics Data System (ADS)

    Zhu, Yuan-Zhi; Zhang, Ya-Feng; Zhao, Chao-Qi; Zhou, Feng

    2014-09-01

    The effect of the microstructure of plates fabricated both in the traditional process, involving casting, hot rolling and cold rolling (HR), and in the novel twin roll casting + cold rolling (TRC) process on the surface quality of presensitized (PS) plates was analyzed by optical microscopy (OM), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDXS). The formation of pores on the surface of the electrolyzed HR plate could be attributed to the presence of approximately 1-μm-sized large Al-Fe precipitates in the HR plate compared to the smaller precipitates in the TRC plate. Moreover, residual graphite lubricants used during the TRC process were entrapped on the surface of the TRC plate during the subsequent rolling process. The entrapped pollutants tended to further deteriorate the formation of pores on the surface of the TRC plate, and no residual carbon was detected on the surface of the HR plate. Furthermore, the surface quality of the TRC plate can be improved by surface cleaning before the cold rolling process, which could dramatically lower the residual graphite on the surface.

  12. A New Guarded Hot Plate Designed for Thermal-Conductivity Measurements at High Temperature

    NASA Astrophysics Data System (ADS)

    Scoarnec, V.; Hameury, J.; Hay, B.

    2015-03-01

    The Laboratoire National de Métrologie et d'Essais has developed a new guarded hot-plate apparatus operating from to in the thermal-conductivity range from to . This facility has been specifically designed for measuring medium thermal-conductivity materials at high temperature on square specimens (100 mm side), which are easier to machine than circular ones. The hot plate and cold plates are similar with a metering section independent from the guard ring. The specimens are laterally isolated by an air gap of 4 mm width and can be instrumented by temperature sensors in order to reduce effects of thermal contact resistances between the specimens and the heating plates. Measurements have been performed on certified reference materials and on "calibrated" materials. Relative deviations between thermal conductivities measured and reference values are less than 5 % in the operating range.

  13. Hot-air flat-plate solar collector-design package

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Report contains design data, performance specifications, and drawings for hot-air flat-plate solar-energy collector. Evaluation consists of tests on thermal performance time constance, and incidence angle modifier test. Results are presented in table and graph form and are analyzed in detail.

  14. The stability of buoyancy-driven gaseous boundary layers over inclined semi-infinite hot plates

    NASA Astrophysics Data System (ADS)

    Rajamanickam, Prabakaran; Coenen, Wilfried; Sanchez, Antonio L.

    2016-11-01

    The free-convective boundary-layer flow that develops over a semi-infinite inclined hot plate is known to become unstable at a finite distance from the leading edge, characterized by a critical value of the Grashof number Grδ based on the local boundary-layer thickness δ. The character of the instability depends on the inclination angle ϕ, measured from the vertical direction. For values of ϕ below a critical value ϕc the instability is characterized by the appearance of spanwise vortices, whereas for ϕ >ϕc the bifurcated flow displays Görtler-like streamwise vortices. The Boussinesq approximation, employed in previous linear stability analyses, ceases to be valid for gaseous flow when the wall-to-ambient temperature ratio θw =Tw /T∞ is not close to unity. The corresponding non-Boussinesq analysis is presented here, accounting also for the variation with temperature of the different transport properties. The base-flow profiles are used in a parallel-flow temporal stability analysis to delineate the dependence of the critical Grashof numbers Grδ on the inclination angles ϕ and on the temperature ratio θw. The analysis provides in particular the values of the crossover inclination angles ϕc (θw) .

  15. Hot Isostatic Press Manufacturing Process Development for Fabrication of RERTR Monolithic Fuel Plates

    SciTech Connect

    Crapps, Justin M.; Clarke, Kester D.; Katz, Joel D.; Alexander, David J.; Aikin, Beverly; Vargas, Victor D.; Montalvo, Joel D.; Dombrowski, David E.; Mihaila, Bogdan

    2012-06-06

    We use experimentation and finite element modeling to study a Hot Isostatic Press (HIP) manufacturing process for U-10Mo Monolithic Fuel Plates. Finite element simulations are used to identify the material properties affecting the process and improve the process geometry. Accounting for the high temperature material properties and plasticity is important to obtain qualitative agreement between model and experimental results. The model allows us to improve the process geometry and provide guidance on selection of material and finish conditions for the process strongbacks. We conclude that the HIP can must be fully filled to provide uniform normal stress across the bonding interface.

  16. Effect of nanostructure on rapid boiling of water on a hot copper plate: a molecular dynamics study

    NASA Astrophysics Data System (ADS)

    Fu, Ting; Mao, Yijin; Tang, Yong; Zhang, Yuwen; Yuan, Wei

    2016-08-01

    Molecular dynamic simulations are performed to study the effects of nanostructure on rapid boiling of water that is suddenly heated by a hot copper plate. The results show that the nanostructure has significant effects on energy transfer from solid copper plate to liquid water and phase change process from liquid water to vapor. The liquid water on the solid surface rapidly boil after contacting with an extremely hot copper plate and consequently a cluster of liquid water moves upward during phase change. The temperature of the water film when it separates from solid surface and its final temperature when the system is at equilibrium strongly depend on the size of the nanostructure. These temperatures increase with increasing size of nanostructure. Furthermore, a non-vaporized molecular layer is formed on the surface of the copper plate even continuous heat flux is passing into water domain through the plate.

  17. Differential effects of weekly and daily exposure to the hot plate on the rat's behavior.

    PubMed

    Espejo, E F; Mir, D

    1994-06-01

    Animals were assigned to two groups: weekly stimulated (WS, n = 30) and daily stimulated (DS, n = 30). Three hot plate tests (55.0 +/- 0.5 degree C, 45 s exposure time) were carried out for each rat. Behavior was videotaped and analyzed by a 14-pattern ethogram and a software package. A cluster analysis revealed that naive rats mainly displayed: i) exploratory patterns (walk-sniff, immobile-sniff), ii) primary noxious-evoked elements (forepaw licking, hindpaw licking, stamping), iii) escape responses (learning posture, jumping), and iv) hindleg withdrawal, an independent noxious-evoked element. The main behavioral changes over time were: i) exploratory behavior was habituated in both groups, ii) sensitization of primary noxious-evoked elements was observed only in the WS group, iii) escape elements were enhanced in both groups, although to less extent in the DS group, and iv) hindleg withdrawal was enhanced in both groups. Furthermore, in the WS group, the nociceptive threshold was significantly decreased, and cluster analysis indicated reliable changes over time. Results suggest that a sensitization phenomenon came about when rats were tested weekly, but was minimized by using the daily testing schedule. This study indicated that an ethological analysis is useful to categorize the rat's patterns in the hot plate test, as well as to follow the gradual changes in responses when repeated measures are used.

  18. Ejaculation induced changes in escape latency in the hot plate test: pharmacological analysis of anxiolytic versus analgesic effect.

    PubMed

    Saldívar-González, A; Fernández-Guasti, A

    1994-02-28

    The possible changes in nociception at various stages of male sexual behaviour were explored in the hot plate test. Although other authors have reported an antinociceptive effect of mating, we failed to find this effect on the hot plate test after several sexual behaviour events. To further explore the possible antinociceptive action of copulation we administered a suboptimal analgesic dose of morphine (0.3 mg/kg i.p.). No change in nociception were observed in animals treated with a subthreshold dose of morphine and tested in the nociception test after ejaculation were observed. Since previous reports have refered that ejaculation produces hypoalgesia when measured in the hot plate test, we attempted to replicate these findings. We found that one ejaculation produces an increase in the latency to escape in male rats previously habituated to the hot plate test. These results suggest a hypoalgesic effect. However, such changes could also be interpreted as alterations in the animals' emotionality. Thus, a group of habituated animals was tested on the switched off plate. An important increase in the escape latency behaviour after ejaculation was observed, while no differences between control animals, without sexual behaviour display, tested on switched on and switched off plate were observed. The participation of the benzodiazepine and opiod systems in the ejaculation effect on the switched off plate was explored. A similar increase in escape latency to that induced by ejaculation was caused by diazepam (1.0 and 2.0 mg/kg). The increase in escape latency induced by ejaculation was prevented by the benzodiazepine antagonist, flumazenil (20.0 mg/kg).(ABSTRACT TRUNCATED AT 250 WORDS)

  19. A neutron detector based on microchannel plates

    SciTech Connect

    MacArthur, D.W.

    1987-06-01

    We propose a large-area neutron detector design based on microchannel plates (MCPs). Two characteristics of the MCP make it ideal as a high-rate neutron detector: (1) its signals can have a very fast rise time, and (2) it can count at a high rate. The MCP-based detector could use both the high-voltage power supplies and the readout electronics designed for a neutron detector based on the multiwire proportional chamber (MWPC).

  20. Aluminum-based hot carrier plasmonics

    NASA Astrophysics Data System (ADS)

    Gong, Tao; Munday, Jeremy N.

    2017-01-01

    Aluminum has recently arisen as an excellent alternative plasmonic material due to its tunability, low optical loss, and CMOS compatibility. However, its use in optoelectronic applications has been limited due to Al oxidation. Herein, we report a semiconductor-free aluminum hot carrier device that exploits the self-terminating oxidation to create an interface barrier for high performance metal-insulator-transparent conducting oxide devices. We find a 300% enhancement of the responsivity compared to similarly reported Au-based devices, resulting in a responsivity up to ˜240 nA/W, and a clear dependence of the open-circuit voltage on incident photon energy. We show that further improvement can be obtained by coupling to plasmonic modes of a metal-insulator-metal structure composed of a nanowire array adjacent to a thin aluminum film, increasing light absorption by a factor of three and enabling tunability of the hot carrier response for improved device performance.

  1. Hot Corrosion of Cobalt-Base Alloys

    DTIC Science & Technology

    1975-06-01

    Cast Alloys : NASA VIA, B-1900, 713C and 738X", Report NASA TN D-7682, Lewis Research Center, Cleveland, Ohio, August 1974. 36. Giggins, C.S. and...resistance of cobalt-base and nickel-base alloys . The contract was accomplished under the technical direction of Dr. H. C. Graham of the Aerospace Research...Interpretation of Results 3. SODIUM SULFATE INDUCED HOT CORROSION OF Co-25Al AND Co-35Cr ALLOYS a. Introduction b. Experimental Co-25Al c. Experimental

  2. Antinociceptive effects of voluntarily ingested buprenorphine in the hot-plate test in laboratory rats.

    PubMed

    Hestehave, Sara; Munro, Gordon; Pedersen, Tina Brønnum; Abelson, Klas S P

    2016-09-27

    Researchers performing experiments on animals should always strive towards the refinement of experiments, minimization of stress and provision of better animal welfare. An adequate analgesic strategy is important to improve post-operative recovery and welfare in laboratory rats and mice. In addition, it is desirable to provide post-operative analgesia using methods that are minimally invasive and stressful. This study investigated the antinociceptive effects of orally administered buprenorphine ingested in Nutella® in comparison with subcutaneous buprenorphine administration. By exposing the animal to a thermal stimulus using a hot plate, significant antinociceptive effects of voluntarily ingested buprenorphine administered in Nutella® were demonstrated. This was evident at doses of 1.0 mg/kg 60 and 120 min post administration (P < 0.01), although antinociceptive effects were not as marked as with subcutaneous administration, and had a later onset. It is advised to administer the oral formulation of buprenorphine in Nutella® in a 10-fold higher dose, as well as approximately 60 min earlier, than with the more commonly employed subcutaneous route of administration.

  3. Analgesic properties of Epilobium angustifolium, evaluated by the hot plate test and the writhing test.

    PubMed

    Tita, B; Abdel-Haq, H; Vitalone, A; Mazzanti, G; Saso, L

    2001-01-01

    The analgesic properties of Epilobium angustifolium (Ea), a plant containing flavonoids with anti-inflammatory activity, have not been sufficiently studied so far. Thus, we decided to evaluate, by the classical hot plate test and the writhing test, the analgesic effect of a dry extract of Ea obtained by evaporating a commercially available mother tincture. In the former assay, the effect of Ea (380 mg/kg) was slightly lower than that of morphine (10 mg/kg s.c.). In the writhing test, which is more sensitive for non-steroidal analgesics, the effect of Ea was already significant (P < 0.05) at 95 mg/kg while at doses > or = 190 mg/kg, its activity was similar to that of lysine acetylsalicylate (300 mg/kg). The LD50 of this dry extract of Ea was 1.4+/-0.1 g/kg. Further studies are necessary for the identification of the active principles and the elucidation of their mechanism of action.

  4. Thermal conductivity of a wide range of alternative refrigerants measured with an improved guarded hot-plate apparatus

    SciTech Connect

    Hammerschmidt, U.

    1995-09-01

    The thermal conductivity of the refrigerants R22, R123, R134a, R142b, R143a, and R152a has been determined as a function of temperature in the range from 300 to 460 K. Measurements were carried out at atmospheric pressure with an improved guarded hot-plate apparatus. The width of the instrument`s gas layer and the temperature difference across the metering section were varied to detect any stray heat transfer. Radiation correction factors were derived from IR absorption spectra. The uncertainty of the measurements is estimated to be 2% at a standard deviation of less than 0.1%. Our data sets are compared with corresponding hot wire results. In contrast to the generally preferred hot wire technique, with its possible electrical and chemical interactions between the wire and the polar refrigerant, there are no such difficulties using a guarded hot-plate apparatus. Our data sets may thus contribute to the discussions on discrepancies in thermal conductivity values from various authors using hot wire as one particular method.

  5. Evaluation of the antinociceptive activities of enaminone compounds on the formalin and hot plate tests in mice

    NASA Astrophysics Data System (ADS)

    Masocha, Willias; Kombian, Samuel B.; Edafiogho, Ivan O.

    2016-02-01

    Recently, we found that methyl 4-(4‧-bromophenyl)aminocyclohex-3-en-6-methyl-2-oxo-1-oate (E139), an anticonvulsant enaminone, has antinociceptive activity in the hot plate test. In this study we evaluated the antinociceptive activity of five anilino enaminones E139, ethyl 4-(4‧-chlorophenyl)amino-6-methyl-2-oxocyclohex-3-en-1-oate (E121), ethyl 4-(4‧-bromophenyl)amino-6-methyl-2-oxocyclohex-3-en-1-oate (E122), methyl 4-(4‧-chlorophenyl)amino-6-methyl-2-oxocyclohex-3-en-1-oate (E138) and ethyl 4-(4‧-fluorophenyl)amino-6-methyl-2-oxocyclohex-3-en-1-oate (BRG 19) using the formalin and hot plate tests. E139 has been reported to exert its effects via enhancement of extracellular GABA levels, thus tiagabine, a GABA transporter inhibitor, was evaluated as a control together with indomethacin. Tiagabine had antinociceptive activity in both phase 1 (neurogenic pain) and phase 2 (inflammatory pain) of the formalin test, whereas indomethacin had activity only in phase 2. E139 and E138 had antinociceptive activity in both phases of the formalin test, whereas E121 had activity only in phase 1 and BRG 19 had activity only in phase 2. E122 had no significant activity in either phase. In the hot plate test only E139 had antinociceptive activity. Administration of either bicuculline, a GABAA receptor antagonist, or CGP 35348, a GABAB receptor antagonist, blocked the antinociceptive activity of E139. In conclusion our results indicate that E139 has antinociceptive activity in the formalin and hot plate tests that are dependent on GABA receptors.

  6. Learning influence on the behavioral structure of rat response to pain in hot-plate.

    PubMed

    Casarrubea, Maurizio; Sorbera, Filippina; Santangelo, Andrea; Crescimanno, Giuseppe

    2011-11-20

    Aim of the research was to study, by means of descriptive and multivariate analyses, whether, and how, learning influences the behavioral structure of rat response to pain. To this purpose, a hot-plate test daily repetition procedure was carried out on male Wistar rats for five days. A 6-day interval without stimulation elapsed before last test was carried out on day 12. After composition of an ethogram, descriptive (number, latency, per cent distribution) and multivariate analyses (cluster, stochastic) were carried out for each scheduled test day. One-way ANOVA and Newman-Keuls post-hoc test for multiple comparisons revealed significant changes for climbing, jumping, front-paw licking and stamping mean latencies. Student's t-test, carried out between days 1 and 12, showed that significant modifications persisted over time only for climbing and jumping. Cluster analysis evidenced three different clusters: exploratory (sniffing, walking), primary noxious evoked elements (front-paw licking, hind-paw licking, stamping), and escape (climbing and jumping), each showing modifications during test repetition. Comparison between days 1 and 12 revealed substantial differences in similarity values of escape patterns whereas, for the response to pain ones, a conservative structure of dendrograms was maintained. Stochastic analysis revealed a progressive increase of transitions toward jumping and a significant reduction of the ones between sniffing and walking. Such modifications persisted also after 6 days without any stimulation. Present study shows that learning provokes a complex and fine temporal evolution of the innermost behavioral structure of rat response to pain aiming at a more efficient escape strategy.

  7. Magma production rate along the Ninetyeast Ridge and its relationship to Indian plate motion and Kerguelen hot spot activity

    NASA Astrophysics Data System (ADS)

    Sreejith, K. M.; Krishna, K. S.

    2015-02-01

    The Ninetyeast Ridge, a linear trace of the Kerguelen hot spot in the Indian Ocean, was emplaced on a rapidly drifting Indian plate. Magma production rates along the ridge track are computed using gravity-derived excess crustal thickness data. The production rates change between 2 and 15 m3/s over timescales of 3-16 Myr. Major variations in magma production rates are primarily associated with significant changes in the Indian plate velocity with low-production phases linked to high plate velocity periods. The lowest magma production rate (2 m3/s) at 62 Ma is associated with the rapid northward drift of Indian plate under the influence of the Reunion mantle plume. The contemporaneous slowing of the African plate coincides with increase in magma production rate along the Walvis Ridge in the Atlantic Ocean. The present study suggests that variations in the Indian plate motion and frequent ridge jumps have a major role in controlling the magma production, particularly on long-period cycles (~16 Myr). Short-period variations (~5 Myr) in magma productions may be associated with intrinsic changes in the plume, possibly due to the presence of solitary waves in the plume conduit.

  8. Laser-Based Characterization of Nuclear Fuel Plates

    SciTech Connect

    James A. Smith; David L. Cottle; Barry H. Rabin

    2013-07-01

    Ensuring the integrity of fuel-clad and clad-clad bonding in nuclear fuels is important for safe reactor operation and assessment of fuel performance, yet the measurement of bond strengths in actual fuels has proved challenging. The laser shockwave technique (LST) originally developed to characterize structural adhesion in composites is being employed to characterize interface strength in a new type of plate fuel being developed at Idaho National Laboratory (INL). LST is a non-contact method that uses lasers for the generation and detection of large-amplitude acoustic waves and is well suited for application to both fresh and irradiated nuclear-fuel plates. This paper will report on initial characterization results obtained from fresh fuel plates manufactured by different processes, including hot isostatic pressing, friction stir welding, and hot rolling.

  9. Laser-based characterization of nuclear fuel plates

    SciTech Connect

    Smith, James A.; Cottle, Dave L.; Rabin, Barry H.

    2014-02-18

    Ensuring the integrity of fuel-clad and clad-clad bonding in nuclear fuels is important for safe reactor operation and assessment of fuel performance, yet the measurement of bond strengths in actual fuels has proved challenging. The laser shockwave technique (LST) originally developed to characterize structural adhesion in composites is being employed to characterize interface strength in a new type of plate fuel being developed at Idaho National Laboratory (INL). LST is a non-contact method that uses lasers for the generation and detection of large-amplitude acoustic waves and is well suited for application to both fresh and irradiated nuclear-fuel plates. This paper will report on initial characterization results obtained from fresh fuel plates manufactured by different processes, including hot isostatic pressing, friction stir welding, and hot rolling.

  10. Site-based data curation based on hot spring geobiology

    PubMed Central

    Palmer, Carole L.; Thomer, Andrea K.; Baker, Karen S.; Wickett, Karen M.; Hendrix, Christie L.; Rodman, Ann; Sigler, Stacey; Fouke, Bruce W.

    2017-01-01

    Site-Based Data Curation (SBDC) is an approach to managing research data that prioritizes sharing and reuse of data collected at scientifically significant sites. The SBDC framework is based on geobiology research at natural hot spring sites in Yellowstone National Park as an exemplar case of high value field data in contemporary, cross-disciplinary earth systems science. Through stakeholder analysis and investigation of data artifacts, we determined that meaningful and valid reuse of digital hot spring data requires systematic documentation of sampling processes and particular contextual information about the site of data collection. We propose a Minimum Information Framework for recording the necessary metadata on sampling locations, with anchor measurements and description of the hot spring vent distinct from the outflow system, and multi-scale field photography to capture vital information about hot spring structures. The SBDC framework can serve as a global model for the collection and description of hot spring systems field data that can be readily adapted for application to the curation of data from other kinds scientifically significant sites. PMID:28253269

  11. Site-based data curation based on hot spring geobiology.

    PubMed

    Palmer, Carole L; Thomer, Andrea K; Baker, Karen S; Wickett, Karen M; Hendrix, Christie L; Rodman, Ann; Sigler, Stacey; Fouke, Bruce W

    2017-01-01

    Site-Based Data Curation (SBDC) is an approach to managing research data that prioritizes sharing and reuse of data collected at scientifically significant sites. The SBDC framework is based on geobiology research at natural hot spring sites in Yellowstone National Park as an exemplar case of high value field data in contemporary, cross-disciplinary earth systems science. Through stakeholder analysis and investigation of data artifacts, we determined that meaningful and valid reuse of digital hot spring data requires systematic documentation of sampling processes and particular contextual information about the site of data collection. We propose a Minimum Information Framework for recording the necessary metadata on sampling locations, with anchor measurements and description of the hot spring vent distinct from the outflow system, and multi-scale field photography to capture vital information about hot spring structures. The SBDC framework can serve as a global model for the collection and description of hot spring systems field data that can be readily adapted for application to the curation of data from other kinds scientifically significant sites.

  12. The transference of heat from a hot plate to an air stream

    NASA Technical Reports Server (NTRS)

    Elias, Franz

    1931-01-01

    The object of the present study was to define experimentally the field of temperature and velocity in a heated flat plate when exposed to an air stream whose direction is parallel to it, then calculate therefrom the heat transference and the friction past the flat plate, and lastly, compare the test data with the mathematical theory. To ensure comparable results, we were to actually obtain or else approximate: a) two-dimensional flow; b) constant plate temperature in the direction of the stream. To approximate the flow in two dimensions, we chose a relatively wide plate and measured the velocity and temperature in the median plane.

  13. Structural Behavior of Monolithic Fuel Plates During Hot Isostatic Pressing and Annealing

    SciTech Connect

    Pavel G. Medvedev; Hakan Ozaltun

    2010-03-01

    This paper presents results of the stress analysis in the monolithic fuel plates during thermal transients performed using COMSOL finite element analysis software. Large difference in the thermal expansion between the U-Mo foil and Al cladding is the main load origin during heating and cooling of the fuel plates. In addition, the mechanical behavior of the plate is affected by the difference in yield points between the foil and the cladding. This is manifested by the plastic deformation and permanent strains in the cladding, and elastic deformation of the foil. The results show existence of the critical temperature points at which the stresses change from compressive to tensile. The paper highlights principal differences in mechanical behavior between monolithic and dispersion fuel plates, underlines the need for mechanical property data, especially for the U-Mo alloys, and discusses the methodology for mechanical analysis of the monolithic plates.

  14. Zero Pressure Gradient Flat Plate Boundary Layer Experiments Using Synchronized PIV and a Hot Wire Anemometry Rake

    NASA Astrophysics Data System (ADS)

    Tutkun, M.; Johansson, P. B. V.; George, W. K.; Stanislas, M.; Foucaut, J. M.; Kostas, J.; Coudert, S.; Delville, J.

    2006-11-01

    Zero pressure gradient flat plate boundary layer experiments have been performed in the 20 meter long test section of the Laboratoire de M'ecanique de Lille, LML, wind tunnel. Measurements were carried out at Reθ=10 000 and Reθ=20 000 using synchronized PIV and a hot wire anemometry rake. The boundary layer thickness at the measurement location was about 30 cm. A hot wire rake of 143 probes was placed in the test section of the wind tunnel to provide the time history of the boundary layer. 2 stereo PIV systems in the wallnormal-spanwise (YZ) plane, and 1 stereo PIV system to record in the streamwise-wallnormal (XY) were used. One high repetition PIV system was used in streamwise-spanwise (XZ) plane. The sampling frequency of the XZ PIV system was 3000 VF/s at Reθ=20 000 and 1500 VF/s at Reθ=10 000.

  15. Microstructure and Mechanical Properties in Hot-Rolled Extra High-Yield-Strength Steel Plates for Offshore Structure and Shipbuilding

    NASA Astrophysics Data System (ADS)

    Liu, Dongsheng; Li, Qingliang; Emi, Toshihiko

    2011-05-01

    Key parameters for a thermomechanically controlled processing and accelerated cooling process (TMCP-AcC) were determined for integrated mass production to produce extra high-yield-strength microalloyed low carbon SiMnCrNiCu steel plates for offshore structure and bulk shipbuilding. Confocal scanning microscopy was used to make in-situ observations on the austenite grain growth during reheating. A Gleeble 3800 thermomechanical simulator was employed to investigate the flow stress behavior, static recrystallization (SRX) of austenite, and decomposition behavior of the TMCP conditioned austenite during continuous cooling. The Kocks-Mecking model was employed to describe the constitutive behavior, while the Johnson-Mehl-Avrami-Kolmogorov (JMAK) approach was used to predict the SRX kinetics. The effects of hot rolling schedule and AcC on microstructure and properties were investigated by test-scale rolling trials. The bridging between the laboratory observations and the process parameter determination to optimize the mass production was made by integrated industrial production trials on a set of a 5-m heavy plate mill equipped with an accelerated cooling system. Successful production of 60- and 50-mm-thick plates with yield strength in excess of 460 MPa and excellent toughness at low temperature (213 K (-60 °C)) in the parent metal and the simulated coarse-grained heat affected zone (CGHAZ) provides a useful integrated database for developing advanced high-strength steel plates via TMCP-AcC.

  16. 21 CFR 872.6200 - Base plate shellac.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Base plate shellac. 872.6200 Section 872.6200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6200 Base plate shellac. (a) Identification. Base...

  17. 21 CFR 872.6200 - Base plate shellac.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Base plate shellac. 872.6200 Section 872.6200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6200 Base plate shellac. (a) Identification. Base...

  18. 21 CFR 872.6200 - Base plate shellac.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Base plate shellac. 872.6200 Section 872.6200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6200 Base plate shellac. (a) Identification. Base...

  19. 21 CFR 872.6200 - Base plate shellac.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Base plate shellac. 872.6200 Section 872.6200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6200 Base plate shellac. (a) Identification. Base...

  20. Harvesting the loss: surface plasmon-based hot electron photodetection

    NASA Astrophysics Data System (ADS)

    Li, Wei; Valentine, Jason G.

    2016-11-01

    Although the nonradiative decay of surface plasmons was once thought to be only a parasitic process within the plasmonic and metamaterial communities, hot carriers generated from nonradiative plasmon decay offer new opportunities for harnessing absorption loss. Hot carriers can be harnessed for applications ranging from chemical catalysis, photothermal heating, photovoltaics, and photodetection. Here, we present a review on the recent developments concerning photodetection based on hot electrons. The basic principles and recent progress on hot electron photodetectors are summarized. The challenges and potential future directions are also discussed.

  1. Harvesting the loss: surface plasmon-based hot electron photodetection

    NASA Astrophysics Data System (ADS)

    Li, Wei; Valentine, Jason G.

    2017-01-01

    Although the nonradiative decay of surface plasmons was once thought to be only a parasitic process within the plasmonic and metamaterial communities, hot carriers generated from nonradiative plasmon decay offer new opportunities for harnessing absorption loss. Hot carriers can be harnessed for applications ranging from chemical catalysis, photothermal heating, photovoltaics, and photodetection. Here, we present a review on the recent developments concerning photodetection based on hot electrons. The basic principles and recent progress on hot electron photodetectors are summarized. The challenges and potential future directions are also discussed.

  2. [COLD or HOT natural attribute of Zuojinwan and Fanzuojinwan based on temperature tropism of mice].

    PubMed

    Yang, Hong-Bo; Zhao, Yan-Ling; Li, Bao-Cai; Wang, Jia-Bo; Li, Rui-Sheng; Jia, Lei; Cheng, Dan-Hong; Xiao, Xiao-He

    2010-06-01

    This study is to investigate the authenticity between COLD and HOT natural attribute in the famous Chinese medicine formulas--Zuojinwan (Coptis-Evodia 6 : 1) and Fanzuojinwan (Coptis-Evodia 1 : 6) based on mice temperature tropism, and establish an objective method to estimate the difference of two natural attribute by using a cold/hot plate differentiating technology. The results indicated that the COLD nature Zuojinwan could decrease significantly the remaining rate of HOT-symptom rat on warm pad (P < 0.05). That was not notable to COLD-symptom rat. The interference result of COLD-HOT temperature tropism to COLD/HOT symptom rat in Fanzuojinwan was the reverse with the COLD nature Zuojinwan. Meanwhile, biochemical indicators which are relative to energy metabolism such as ATPase enzyme activity and total anti-oxidant capability (T-AOC), had corresponding change in the organism. In the study, the COLD and HOT natural tendency in Zuojinwan and Fanzuojinwan which were composed by the same herbs with different proportion could be expressed qualitatively, quantitatively, objectively and directly with applying animal temperature tropism, and be verified to philosophical idea of treating disease theory with "expelling heat with cold herbs and cryopathy requiring warm prescription", not "expelling heat with heat herbs and cryopathy requiring cold prescription" in ancient traditional Chinese medicine, which brings a new approach in investigation of the nature theory of traditional Chinese medicine.

  3. Application of MMC model on simulation of shearing process of thick hot-rolled high strength steel plate

    NASA Astrophysics Data System (ADS)

    Dong, Liang; Li, Shuhui; Yang, Bing; Gao, Yongsheng

    2013-12-01

    Shear operation is widely used as the first step in sheet metal forming to cut the sheet or plate into the required size. The shear of thick hot-rolled High Strength Steel (HSS) requires large shearing force and the sheared edge quality is relatively poor because of the large thickness and high strength compared with the traditional low carbon steel. Bad sheared edge quality will easily lead to edge cracking during the post-forming process. This study investigates the shearing process of thick hot-rolled HSS plate metal, which is generally exploited as the beam of heavy trucks. The Modified Mohr-Coulomb fracture criterion (MMC) is employed in numerical simulation to calculate the initiation and propagation of cracks during the process evolution. Tensile specimens are designed to obtain various stress states in tension. Equivalent fracture strains are measured with Digital Image Correlation (DIC) equipment to constitute the fracture locus. Simulation of the tension test is carried out to check the fracture model. Then the MMC model is applied to the simulation of the shearing process, and the simulation results show that the MMC model predicts the ductile fracture successfully.

  4. Base plate mechanics of the barnacle Balanus amphitrite (=Amphibalanus amphitrite).

    PubMed

    Ramsay, David B; Dickinson, Gary H; Orihuela, Beatriz; Rittschof, Daniel; Wahl, Kathryn J

    2008-01-01

    The mechanical properties of barnacle base plates were measured using a punch test apparatus, with the purpose of examining the effect that the base plate flexural rigidity may have on adhesion mechanics. Base plate compliance was measured for 43 Balanus amphitrite (=Amphibalanus amphitrite) barnacles. Compliance measurements were used to determine flexural rigidity (assuming a fixed-edge circular plate approximation) and composite modulus of the base plates. The barnacles were categorized by age and cement type (hard or gummy) for statistical analyses. Barnacles that were 'hard' (> or =70% of the base plate thin, rigid cement) and 'gummy' (>30% of the base plate covered in compliant, tacky cement) showed statistically different composite moduli but did not show a difference in base plate flexural rigidity. The average flexural rigidity for all barnacles was 0.0020 Nm (SEM +/- 0.0003). Flexural rigidity and composite modulus did not differ significantly between 3-month and 14-month-old barnacles. The relatively low flexural rigidity measured for barnacles suggests that a rigid punch approximation is not sufficient to account for the contributions to adhesion mechanics due to flexing of real barnacles during release.

  5. Fractal zone plate beam based optical tweezers

    PubMed Central

    Cheng, Shubo; Zhang, Xinyu; Ma, Wenzhuo; Tao, Shaohua

    2016-01-01

    We demonstrate optical manipulation with an optical beam generated by a fractral zone plate (FZP). The experimental results show that the FZP beam can simultaneously trap multiple particles positioned in different focal planes of the FZP beam, owing to the multiple foci and self-reconstruction property of the FZP beam. The FZP beam can also be used to construct three-dimensional optical tweezers for potential applications. PMID:27678305

  6. High-Pressure, High-Temperature Equations of State Using Fabricated Controlled-Geometry Ni/SiO2 Double Hot-Plate Samples

    NASA Astrophysics Data System (ADS)

    Pigott, J. S.; Ditmer, D. A.; Fischer, R. A.; Reaman, D. M.; Davis, R. J.; Panero, W. R.

    2014-12-01

    To model and predict the structure, dynamics, and composition of Earth's deep interior, accurate and precise measurements of thermal expansion and compressibility are required. The laser-heated diamond-anvil cell (LHDAC) coupled with synchrotron-based x-ray diffraction (XRD) is a powerful tool to determine pressure-volume-temperature (P-V-T) relationships. However, LHDAC experiments may be hampered by non-uniform heating caused by the mixing of transparent materials with opaque laser absorbers. Additionally, radial temperature gradients are exacerbated by small misalignments (1-3 µm) of the x-ray beam with respect to the center of the laser-heated hotspot. We have fabricated three-dimensional, controlled-geometry, double hot-plate samples. In this double hot-plate arrangement, a transparent oxide layer (SiO2) is sandwiched between two laser absorbing layers (Ni) in a single, cohesive sample. These samples were mass manufactured (>105 samples) using a combination of physical vapor deposition, photolithography, wet etching, and plasma etching. The double hot-plate arrangement coupled with the chemical and spatial homogeneity of the laser absorbing layers addresses problems caused by mixtures of transparent and opaque samples. The controlled-geometry samples have dimensions of 50 μm x 50 μm x 1.4 μm. The dimensions of the samples are much larger than the synchrotron x-ray beam. With a heating laser FWHM of ~50 μm, the radial temperature gradients within the volume probed by the x-ray are reduced. We conducted XRD experiments to P > 50 GPa and T > 2200 K at beamline 16-ID-B (HPCAT) of the Advanced Photon Source. Here we present relevant thermal modeling of the LHDAC environment along with Ni and SiO2 P-V-T equations of state. Our photolithography method of sample fabrication can be extended to different materials including but not limited to Fe and MgO.

  7. Detection system for inclusion defects in hot-rolled steel plates using MFLT with two different magnetizing strengths

    NASA Astrophysics Data System (ADS)

    Yotsuji, Junichi; Koshihara, Takahiro

    2014-02-01

    Recently, steel can manufacturing requires higher quality because otherwise minute non-metallic inclusions in thin sheets cause cracks and result in a burst during pressurization after the pressing process. Quality testing systems have already been installed in the final process in steel plants, but if there were another inspection in an earlier step, for example, at the hot strip mill, the mass manufacture of nonconforming products could be avoided and maintaining quality control would be more efficient. In order to detect inclusion defects in hot-rolled steel plates, the authors developed a new technique for MFLT (Magnetic Flux Leakage Testing) using different magnetizing forces. According to an analysis of the noise factors in MFLT, it was found that the signals generated from the scale layer on a steel surface are dominant. A different magnetizing force method is the used to decrease this overpowering noise level in MFLT. In this paper, it was confirmed that inclusions larger than 160μm in diameter and less than 0.45mm in depth can be detected utilizing this method.

  8. MANTLE CONVECTION, PLATE TECTONICS, AND VOLCANISM ON HOT EXO-EARTHS

    SciTech Connect

    Van Summeren, Joost; Conrad, Clinton P.; Gaidos, Eric

    2011-07-20

    Recently discovered exoplanets on close-in orbits should have surface temperatures of hundreds to thousands of Kelvin. They are likely tidally locked and synchronously rotating around their parent stars and, if an atmosphere is absent, have surface temperature contrasts of many hundreds to thousands of Kelvin between permanent day and night sides. We investigated the effect of elevated surface temperature and strong surface temperature contrasts for Earth-mass planets on the (1) pattern of mantle convection, (2) tectonic regime, and (3) rate and distribution of partial melting, using numerical simulations of mantle convection with a composite viscous/pseudo-plastic rheology. Our simulations indicate that if a close-in rocky exoplanet lacks an atmosphere to redistribute heat, a {approx}>400 K surface temperature contrast can maintain an asymmetric degree 1 pattern of mantle convection in which the surface of the planet moves preferentially toward subduction zones on the cold night side. The planetary surface features a hemispheric dichotomy, with plate-like tectonics on the night side and a continuously evolving mobile lid on the day side with diffuse surface deformation and vigorous volcanism. If volcanic outgassing establishes an atmosphere and redistributes heat, plate tectonics is globally replaced by diffuse surface deformation and volcanism accelerates and becomes distributed more uniformly across the planetary surface.

  9. Ultrasonic plate waves in wood-based composite panels

    NASA Astrophysics Data System (ADS)

    Tucker, Brian James

    Two key shortcomings of current ultrasonic nondestructive evaluation (NDE) techniques for plywood, medium density fiberboard (MDF), and oriented strandboard are the reliance on empirical correlations and the neglect of valuable waveform information. The research reported herein examined the feasibility of using fundamental physical relationships along with advanced signal analysis to evaluate material properties and locate defects in wood-based composite panels. Dispersion curves were constructed exhibiting the variation of ultrasonic flexural plate wave phase velocity with frequency. Based on shear deformation plate wave theory, flexural and transverse shear rigidity values for a variety of wood-based composite panels were obtained from the dispersion curves. Axial rigidity values were obtained directly from extensional plate wave phase velocity. Excellent agreement (within 5%) of flexural rigidity values was obtained between NDE and mechanical testing for thin panels (less than or equal to 6.4 mm). Transverse shear rigidity values were obtained from NDE, but no reliable mechanical results were obtained for comparison. Tensile and compressive axial rigidity values obtained from NDE were from 12% to 31% and from 22% to 41% higher than mechanical tension and compression test results, respectively. These differences between NDE and axial mechanical testing results are likely due to load-rate effects. Nondestructive rigidity results for thicker panels using the setup described herein were either unreliable or not interpretable due to highly attenuated signals and/or violation of plate wave assumptions. Shear deformation laminated plate theory was used to predict flexural and axial laminate rigidity values of wood-based laminates from NDE measurements to within 3% and 25%, respectively. Plate wave NDE was also used to successfully locate a 60-mm square delaminated area within a 6.4-mm thick MDF laminate. This fundamental research advances the state-of-the-art of wood-based

  10. Predictive Capability for Hot Spot Ignition of Double Base Propellants

    DTIC Science & Technology

    2009-08-01

    propellants are composed of nitrocellulose and stirred with a reactive plasticizer liquid nitrate ester such as nitroglycerine which also affects the oxygen...Predictive Capability for Hot Spot Ignition of Double Base Propellants by Stephan R. Bilyk ARL-RP-261 August 2009...Ignition of Double Base Propellants Stephan R. Bilyk Weapons and Materials Research Directorate, ARL A reprint from the 2006

  11. Stochastic and hybrid-stress plate/shell finite elements for hot-section components

    NASA Technical Reports Server (NTRS)

    Atluri, S. N.

    1987-01-01

    The research effort in the Center for the Advancement of Computational Mechanics at Georgia Tech has two main thrusts. The first of these is the development of special approaches for the numerical stress analysis of solids and structures whose material and geometric properties are uncertain. The second seeks to develop and implement high-efficiency plate and shell elements. The stochastic element method, currently being implemented, will be able to more accurately portray the probabilistic nature of stress, strain, and displacement in actual structures. Current research has provided a hybrid-stress shell element whose behavior is acceptable for aspect ratios as high as 30 to 1. Thus, substantially more complex analyses will be practicable as soon as this element is fully implemented. An additional advantage of the hybrid approach is that it permits more accurate stress-recovery at the upper and lower surfaces of the shell, an important consideration in high thickness-gradient applications. The software associated with the above research is being implemented in the form of extensions to the Nessus code. The hybrid shell element has been successfully tested in several small-deformation elastic analyses. The theoretical formulation of the stochastic elements is essentially complete; its implementation is just beginning.

  12. Juan Fernández Ridge (Nazca Plate): petrology and thermochronology of a rejuvenated hot spot trail

    NASA Astrophysics Data System (ADS)

    Reyes, J.; Lara, L. E.

    2012-04-01

    The Juan Fernández Ridge on the oceanic Nazca plate is thought to be a classic hot spot trail because of the apparent westward rejuvenation of the eruptive ages. However, geochronological data is still scarce and there are a few constrains to support this hypothesis like the ca. 9 Ma Ar-Ar age of the O'Higgins seamount (115 km from the Chile-Perú trench), some published K-Ar ages of ca. 3-4 Ma in Robinson Crusoe island (580 km from the trench) and ca. 1 Ma in Alejandro Selkirk (180 km further west). New reconnaissance K-Ar ages and specially the ongoing Ar-Ar dating effort in Robinson Crusoe define a ca. 1-4 Ma time span, which partially overlap with the age of Alejandro Selkirk, breaking the expected age progression given that the Nazca plate moves eastwards at ca. 6-8 cm/yr. In addition, new geological mapping shows a sharp unconformity between the older (ca. 4 Ma), strongly altered sequences and the more recent (ca. 1 Ma), post-erosional volcanic piles, where the proximal facies are still preserved. Petrological evidence also supports this evolution pattern. In fact, the partially altered older sequence is tholeiitic (Ba/Yb=12.70; La/Yb=8.12; Ba/Y=6.51; Ba/Zr=0.89). The shield stage (ca. 1-3 Ma) is transicional from tholeiitic to alkaline (Ba/Yb=18.07-8.32; La/Yb=4.59-9.84; Ba/Y=4.24-8.18; Ba/Zr=0.73-1.09) and the younger (ca. 1 Ma) is mostly alkaline (Ba/Yb=38.15; La/Yb=15.66; Ba/Y=20.27; Ba/Zr=2.31). A fixed deep-mantle plume origin for Pacific hot spots has been widely debated and concurrent phenomena arose as a possible explanation for non-linear age progressions and/or long-lived volcanic activity. In fact, intraplate regional tectonics, plume displacement, and mantle heterogeneities could be the main factor of the ridge architecture or the mask for a first-order linear trend. An ongoing mapping and dating effort is aimed to understand the evolution of the Juan Fernández Ridge, testing the main hypothesis. This research is supported by FONDECYT Project

  13. Hierarchic plate and shell models based on p-extension

    NASA Technical Reports Server (NTRS)

    Szabo, Barna A.; Sahrmann, Glenn J.

    1988-01-01

    Formulations of finite element models for beams, arches, plates and shells based on the principle of virtual work was studied. The focus is on computer implementation of hierarchic sequences of finite element models suitable for numerical solution of a large variety of practical problems which may concurrently contain thin and thick plates and shells, stiffeners, and regions where three dimensional representation is required. The approximate solutions corresponding to the hierarchic sequence of models converge to the exact solution of the fully three dimensional model. The stopping criterion is based on: (1) estimation of the relative error in energy norm; (2) equilibrium tests, and (3) observation of the convergence of quantities of interest.

  14. Cancer incidence among population utilizing geothermal hot water: a census-based cohort study.

    PubMed

    Kristbjornsdottir, Adalbjorg; Rafnsson, Vilhjalmur

    2013-12-15

    The aim of the study was to assess whether utilization of geothermal hot-water is associated with risk of cancer. The cohort from census was followed from 1981 to 2010 in nation-wide death and cancer registries. The moving apart of American-Eurasian tectonic plates, observed in Iceland, results in high volcanic activity. The definition of the study populations was based on geological information. The target population was inhabitants of communities located on bedrock younger than 3.3 million years, utilizing hot-water supply generated from geothermal wells since 1972. The two reference populations were inhabitants of communities without this hot-water supply located on areas with less volcanic/geothermal activity, and bedrock older than 3.3 million years. Hazard ratio (HR), and 95% confidence intervals (CI) were adjusted for age, gender, education, housing, reproductive factors and smoking. HR in the geothermal hot-water supply areas for all cancer was 1.15 (95% CI 1.05-1.25) as compared with nongeothermal areas. The HR for breast cancer was 1.40 (1.12-1.75), prostate cancer 1.61 (1.29-2.00), kidney cancer 1.64 (1.11-2.41), lymphatic and haematopoietic tissue cancers 1.45 (1.08-1.95), and for basal cell carcinoma (BCC) of the skin 1.46 (1.16-1.82). Positive exposure-response relations were observed between the risk of these cancers and the degree of volcanic/geothermal activity in the reference areas. Increased incidence of all cancers, breast, prostate, kidney cancer and BCC of the skin was found among the population utilizing geothermal hot-water for decades. More precise information on exposure is needed in future studies.

  15. Microtiter plate-based antibody microarrays for bacteria and toxins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Research has focused on the development of rapid biosensor-based, high-throughput, and multiplexed detection of pathogenic bacteria in foods. Specifically, antibody microarrays in 96-well microtiter plates have been generated for the purpose of selective detection of Shiga toxin-producing E. coli (...

  16. Gasoline identifier based on SH0 plate acoustic waves.

    PubMed

    Kuznetsova, Iren E; Zaitsev, Boris D; Seleznev, Eugenii P; Verona, Enrico

    2016-08-01

    The present paper is devoted to the development of gasoline identifier based on zero order shear-horizontal (SH0) acoustic wave propagating in piezoelectric plate. It has been found that the permittivity of gasoline is increased when its octane number rises. The development of such identifier is experimentally demonstrated to be possible.

  17. Fabrication of tunable plasmonic substrates using a table-top gold coater and a hot plate, their optical characterization, and surface enhanced Raman activity

    NASA Astrophysics Data System (ADS)

    Arora, A.; Krishnan, A.

    2015-10-01

    We present a simple scalable technique for repeatable fabrication of large area (cm2) electromagnetic hot spots using tunable Localized Surface Plasmon Resonance (LSPR) substrates and their k-space microscopic imaging characterization. The substrates were fabricated simply using a low vacuum air plasma scanning electron microscope gold coater and annealing using a hot plate. The measured permittivity profile and optical transmission characteristics of such substrates showed large changes before and after annealing, with clear changes in the occurrence and position of the LSPR in the visible spectrum. Furthermore, the LSPR wavelength of these substrates was tuned from 537 nm to 630 nm using cyclic deposition and annealing. It was observed that every anneal step could be used to blue shift the resonance, while a deposition step could be used to red shift the resonance, thus giving rise to a wide tunability. We also present the k-space images of the substrates using narrowband fluorescence leakage radiation microscopy and broadband polarization microscopy. The enhanced scattering in these substrates was clearly imaged in the k-space, and the color content in the broadband k-space images correlates well with the spectral characteristics of these substrates that can be used in commercial quality testing without a spectrometer. The optical characteristics of the substrates were attributed to the morphology evolution verified using scanning probe microscopy. A single particle model based simulation was used to evaluate the optical response. The substrates were then tested for surface enhanced Raman spectroscopy (SERS) activity using control experiments involving Rhodamine 6G dye in PMMA matrix of different concentrations with analyte volumes of approximately 200 pl and analytical enhancements of >3 ×104 (net enhancement >1.8 ×107 ) were obtained. The limit of detection was ≈ 10-8 M in low volume (≈200 pl) analyte, reaching the regime of few molecule detection. To

  18. Hot Carrier-Based Near-Field Thermophotovoltaic Energy Conversion.

    PubMed

    St-Gelais, Raphael; Bhatt, Gaurang Ravindra; Zhu, Linxiao; Fan, Shanhui; Lipson, Michal

    2017-03-28

    Near-field thermophotovoltaics (NFTPV) is a promising approach for direct conversion of heat to electrical power. This technology relies on the drastic enhancement of radiative heat transfer (compared to conventional blackbody radiation) that occurs when objects at different temperatures are brought to deep subwavelength distances (typically <100 nm) from each other. Achieving such radiative heat transfer between a hot object and a photovoltaic (PV) cell could allow direct conversion of heat to electricity with a greater efficiency than using current solid-state technologies (e.g., thermoelectric generators). One of the main challenges in the development of this technology, however, is its incompatibility with conventional silicon PV cells. Thermal radiation is weak at frequencies larger than the ∼1.1 eV bandgap of silicon, such that PV cells with lower excitation energies (typically 0.4-0.6 eV) are required for NFTPV. Using low bandgap III-V semiconductors to circumvent this limitation, as proposed in most theoretical works, is challenging and therefore has never been achieved experimentally. In this work, we show that hot carrier PV cells based on Schottky junctions between silicon and metallic films could provide an attractive solution for achieving high efficiency NFTPV electricity generation. Hot carrier science is currently an important field of research and several approaches are investigated for increasing the quantum efficiency (QE) of hot carrier generation beyond conventional Fowler model predictions. If the Fowler limit can indeed be overcome, we show that hot carrier-based NFTPV systems-after optimization of their thermal radiation spectrum-could allow electricity generation with up to 10-30% conversion efficiencies and 10-500 W/cm(2) generated power densities (at 900-1500 K temperatures). We also discuss how the unique properties of thermal radiation in the extreme near-field are especially well suited for investigating recently proposed approaches

  19. Development of a System to Measure Austenite Grain Size of Plate Steel Using Laser-Based Ultrasonics

    SciTech Connect

    Lim, C. S.; Hong, S. T.; Yi, J. K.; Choi, S. G.; Oh, K. J.; Nagata, Y.; Yamada, H.; Hamada, N.

    2007-03-21

    A measurement system for austenite grain size of plate steel using laser-based ultrasonics has been developed. At first, the relationship between the ultrasonic attenuation coefficients using longitudinal waves and austenite grain size of samples was investigated in the laboratory experiments. According to the experimental results, the ultrasonic attenuation coefficients showed a good correlation with actual austenite grain sizes. For the next step, the system was installed in a hot rolling pilot plant of plate steel, and it was verified that the austenite grain size could be measured even in the environment of a hot rolling pilot plant. In the experiments, it was also confirmed that the fiber delivery system could deliver Nd:YAG laser beam of 810 mJ/pulse and ultrasonic signals could be obtained successfully.

  20. Leak Location in Plates Using Spatial Fourier Transform Based Analysis

    NASA Astrophysics Data System (ADS)

    Roberts, R.; Holland, S.; Strei, M.; Song, J.; Chimenti, D. E.

    2005-04-01

    The location of air leaks in plate-like structures is examined using a spatial Fourier transform based analysis. Noise data is collected over 2-D spatial arrays at sensor locations, from which mean cross-correlations are compiled. Propagation properties, transit times, and energy distribution among modes are extracted through spatial Fourier transformation of these data. A simple algorithm to determine source location using a reduced set of transform data is demonstrated experimentally, based upon extraction of energy propagation direction.

  1. Phase decomposition of γ-U (bcc) in U-10 wt% Mo fuel alloy during hot isostatic pressing of monolithic fuel plate

    NASA Astrophysics Data System (ADS)

    Park, Y.; Eriksson, N.; Newell, R.; Keiser, D. D.; Sohn, Y. H.

    2016-11-01

    Eutectoid decomposition of γ-phase (cI2) into α-phase (oC4) and γ‧-phase (tI6) during the hot isostatic pressing (HIP) of the U-10 wt% Mo (U10Mo) alloy was investigated using monolithic fuel plate samples consisting of U10Mo fuel alloy, Zr diffusion barrier and AA6061 cladding. The decomposition of the γ-phase was observed because the HIP process is carried out near the eutectoid temperature, 555 °C. Initially, a cellular structure, consisting of γ‧-phase surrounded by α-phase, developed from the destabilization of the γ-phase. The cellular structure further developed into an alternating lamellar structure of α- and γ‧-phases. Using scanning electron microscopy and transmission electron microscopy, qualitative and quantitative microstructural analyses were carried out to identify the phase constituents, and elucidate the microstructural development based on time-temperature-transformation diagram of the U10Mo alloy. The destabilization of γ -phase into α- and γ‧-phases would be minimized when HIP process was carried out with rapid ramping/cooling rate and dwell temperature higher than 560 °C.

  2. Hot spot management through design based metrology: measurement and filtering

    NASA Astrophysics Data System (ADS)

    Lee, Taehyeong; Yang, Hyunjo; Kim, Jungchan; Jung, Areum; Yoo, Gyun; Yim, Donggyu; Park, Sungki; Ishikawa, Akio; Yamamoto, Masahiro; Vikram, Abhishek

    2009-12-01

    Recently several Design Based Metrologies (DBMs) are introduced and being in use for wafer verification. The major applications of DBM are OPC accuracy improvement, DFM feed-back through Process Window Qualification (PWQ) and advanced process control. In general, however, the amount of output data from DBM is normally so large that it is very hard to handle the data for valuable feed-back. In case of PWQ, more than thousands of hot spots are detected on a single chip at the edge of process window. So, it takes much time and labor to review and analyze all the hot spots detected at PWQ. Design-related systematic defects, however, will be found repeatedly and if they can be classified into groups, it would be possible to save a lot of time for the analysis. We have demonstrated an EDA tool which can handle the large amount of output data from DBM by classifying pattern defects into groups. It can classify millions of patterns into less than thousands of pattern groups. It has been evaluated on the analysis of PWQ of metal layer in NAND Flash memory device and random contact hole patterns in a DRAM device. Also, verification was tuned to specific needs of the designer as well as defect analysis engineers by use of EDA tool's 'Pattern Matching Function'. The verification result was well within the required specification of the designer as well as the analysis engineer. The procedures of Hot Spot Management through Design Based Metrology are presented in detail.

  3. Plate-Based Fuel Processing System Final Report

    SciTech Connect

    Carlos Faz; Helen Liu; Jacques Nicole; David Yee

    2005-12-22

    took the initial steam reforming plate-reactor concept and advanced it towards an integrated fuel processing system. A substantial amount of modeling was performed to guide the catalyst development and prototype hardware design and fabrication efforts. The plate-reactor mechanical design was studied in detail to establish design guidelines which would help the plate reactor survive the stresses of repeated thermal cycles (from start-ups and shut-downs). Integrated system performance modeling was performed to predict system efficiencies and determine the parameters with the most significant impact on efficiency. In conjunction with the modeling effort, a significant effort was directed towards catalyst development. CESI developed a highly active, sulfur tolerant, coke resistant, precious metal based reforming catalyst. CESI also developed its own non-precious metal based water-gas shift catalyst and demonstrated the catalysts durability over several thousands of hours of testing. CESI also developed a unique preferential oxidation catalyst capable of reducing 1% CO to < 10 ppm CO over a 35 C operating window through a single pass plate-based reactor. Finally, CESI combined the modeling results and steam reforming catalyst development efforts into prototype hardware. The first generation 3kW(e) prototype was fabricated from existing heat-exchanger plates to expedite the fabrication process. This prototype demonstrated steady state operation ranging from 5 to 100% load conditions. The prototype also demonstrated a 20:1 turndown ratio, 10:1 load transient operation and rapid start-up capability.

  4. Hot corrosion of S-57, 1 cobalt-base alloy

    NASA Technical Reports Server (NTRS)

    Santoro, G. J.

    1977-01-01

    A cobalt base alloy, S-57, was hot corrosion tested in Mach 0.3 burner rig combustion gases at maximum alloy temperatures of 900 and 1000 C. Various salt concentrations were injected into the burner: 0.5, 2, 5, and 10 ppm synthetic sea salt and 4 ppm sodium sulfate (Na2SO4). S-57 underwent accelerated corrosion only under the most severe test conditions, for example, 4 ppm Na2SO4 at 900 C. The process of the accelerated corrosion was primarily sulfidation.

  5. Time Dependent Antinociceptive Effects of Morphine and Tramadol in the Hot Plate Test: Using Different Methods of Drug Administration in Female Rats

    PubMed Central

    Gholami, Morteza; Saboory, Ehsan; Mehraban, Sogol; Niakani, Afsaneh; Banihabib, Nafiseh; Azad, Mohamad-Reza; Fereidoni, Javid

    2015-01-01

    Morphine and tramadol which have analgesic effects can be administered acutely or chronically. This study tried to investigate the effect of these drugs at various times by using different methods of administration (intraperitoneal, oral, acute and chronic). Sixty adult female rats were divided into six groups. They received saline, morphine or tramadol (20 to 125 mg/Kg) daily for 15 days. A hot plate test was performed for the rats at the 1st, 8th and 15th days. After drug withdrawal, the hot plate test was repeated at the 17th, 19th, and 22nd days. There was a significant correlation between the day, drug, group, and their interaction (P<0.001). At 1st day (d1), both morphine, and tramadol caused an increase in the hot plate time comparing to the saline groups (P<0.001), while there was no correlation between drug administration methods of morphine and/or tramadol. At the 8th day (d8), morphine and tramadol led to the most powerful analgesic effect comparing to the other experimental days (P<0.001). At the 15th day (d15), their effects diminished comparing to the d8. After drug withdrawal, analgesic effect of morphine, and tramadol disappeared. It can be concluded that the analgesic effect of morphine and tramadol increases with the repeated use of them. Thereafter, it may gradually decrease and reach to a level compatible to d1. The present data also indicated that although the analgesic effect of morphine and tramadol is dose-and-time dependent, but chronic exposure to them may not lead to altered nociceptive responses later in life. PMID:25561936

  6. Hot Isostatic Press Can Optimization for Aluminum Cladding of U-10Mo Reactor Fuel Plates: FY12 Final Report and FY13 Update

    SciTech Connect

    Clarke, Kester D.; Crapps, Justin M.; Scott, Jeffrey E.; Aikin, Beverly; Vargas, Victor D.; Dvornak, Matthew J.; Duffield, Andrew N.; Weinberg, Richard Y.; Alexander, David J.; Montalvo, Joel D.; Hudson, Richard W.; Mihaila, Bogdan; Liu, Cheng; Lovato, Manuel L.; Dombrowski, David E.

    2013-08-26

    Currently, the proposed processing path for low enriched uranium – 10 wt. pct. molybdenum alloy (LEU-10Mo) monolithic fuel plates for high power research and test reactors includes hot isostatic pressing (HIP) to bond the aluminum cladding that encapsulates the fuel foil. Initial HIP experiments were performed at Idaho National Laboratory (INL) on approximately ¼ scale “mini” fuel plate samples using a HIP can design intended for these smaller experimental trials. These experiments showed that, with the addition of a co-rolled zirconium diffusion barrier on the LEU-10Mo alloy fuel foil, the HIP bonding process is a viable method for producing monolithic fuel plates. Further experimental trials at Los Alamos National Laboratory (LANL) effectively scaled-up the “mini” can design to produce full-size fuel prototypic plates. This report summarizes current efforts at LANL to produce a HIP can design that is further optimized for higher volume production runs. The production-optimized HIP can design goals were determined by LANL and Babcock & Wilcox (B&W) to include maintaining or improving the quality of the fuel plates produced with the baseline scaled-up mini can design, while minimizing material usage, improving dimensional stability, easing assembly and disassembly, eliminating machining, and significantly reducing welding. The initial small-scale experiments described in this report show that a formed-can approach can achieve the goals described above. Future work includes scaling the formed-can approach to full-size fuel plates, and current progress toward this goal is also summarized here.

  7. Irradiation Performance of U-Mo Alloy Based ‘Monolithic’ Plate-Type Fuel – Design Selection

    SciTech Connect

    A. B. Robinson; G. S. Chang; D. D. Keiser, Jr.; D. M. Wachs; D. L. Porter

    2009-08-01

    A down-selection process has been applied to the U-Mo fuel alloy based monolithic plate fuel design, supported by irradiation testing of small fuel plates containing various design parameters. The irradiation testing provided data on fuel performance issues such as swelling, fuel-cladding interaction (interdiffusion), blister formation at elevated temperatures, and fuel/cladding bond quality and effectiveness. U-10Mo (wt%) was selected as the fuel alloy of choice, accepting a somewhat lower uranium density for the benefits of phase stability. U-7Mo could be used, with a barrier, where the trade-off for uranium density is critical to nuclear performance. A zirconium foil barrier between fuel and cladding was chosen to provide a predictable, well-bonded, fuel-cladding interface, allowing little or no fuel-cladding interaction. The fuel plate testing conducted to inform this selection was based on the use of U-10Mo foils fabricated by hot co-rolling with a Zr foil. The foils were subsequently bonded to Al-6061 cladding by hot isostatic pressing or friction stir bonding.

  8. Acoustic Plate Mode sensing in liquids based on free and electrically shorted plate surfaces.

    PubMed

    Anisimkin, V I; Caliendo, C; Verona, E

    2016-05-01

    The sensing behavior to liquids for Acoustic Plate Modes (APMs) propagating along 64°Y, 90°X LiNbO3 plate was investigated vs. two electric boundary conditions. The changes in the APMs phase velocity and attenuation were measured upon exposure to different liquids wetting one of the surfaces of the plate, either free or electrically shorted by a thin conductive Al layer. The experimental data confirm that the presence of a metallic layer covering one of the plate surfaces affects the viscosity and temperature sensitivity of the device. The differences between the sensor response for various liquids, with free or metalized faces, are interpreted in terms of the APM polarization.

  9. Assessment of Uncertainties for the NIST 1016 mm Guarded-Hot-Plate Apparatus: Extended Analysis for Low-Density Fibrous-Glass Thermal Insulation

    PubMed Central

    Zarr, Robert R.

    2010-01-01

    An assessment of uncertainties for the National Institute of Standards and Technology (NIST) 1016 mm Guarded-Hot-Plate apparatus is presented. The uncertainties are reported in a format consistent with current NIST policy on the expression of measurement uncertainty. The report describes a procedure for determination of component uncertainties for thermal conductivity and thermal resistance for the apparatus under operation in either the double-sided or single-sided mode of operation. An extensive example for computation of uncertainties for the single-sided mode of operation is provided for a low-density fibrous-glass blanket thermal insulation. For this material, the relative expanded uncertainty for thermal resistance increases from 1 % for a thickness of 25.4 mm to 3 % for a thickness of 228.6 mm. Although these uncertainties have been developed for a particular insulation material, the procedure and, to a lesser extent, the results are applicable to other insulation materials measured at a mean temperature close to 297 K (23.9 °C, 75 °F). The analysis identifies dominant components of uncertainty and, thus, potential areas for future improvement in the measurement process. For the NIST 1016 mm Guarded-Hot-Plate apparatus, considerable improvement, especially at higher values of thermal resistance, may be realized by developing better control strategies for guarding that include better measurement techniques for the guard gap thermopile voltage and the temperature sensors. PMID:27134779

  10. The effects of oxotremorine, epibatidine, atropine, mecamylamine and naloxone in the tail-flick, hot-plate, and formalin tests in the naked mole-rat (Heterocephalus glaber).

    PubMed

    Dulu, Thomas D; Kanui, Titus I; Towett, Philemon K; Maloiy, Geoffrey M; Abelson, Klas S P

    2014-01-01

    The naked mole-rat (Heterocephalus glaber) is a promising animal model for the study of pain mechanisms, therefore a thorough characterization of this species is essential. The aim of the present study was to establish the naked mole-rat as a model for studying the cholinergic receptor system in antinociception by investigating the involvement of muscarinic, nicotinic and opioid receptors in nociceptive tests in this species. The effects of systemic administration of the muscarinic receptor agonist oxotremorine and the nicotinic receptor agonist epibatidine were investigated in the tail-flick, the hot-plate, and the formalin tests. The effects of co-administration of the muscarinic receptor antagonist atropine, the nicotinic receptor antagonist mecamylamine, and the opioid receptor antagonist naloxone were also investigated. Oxotremorine and epibatidine induced a significant, dose-dependent antinociceptive effect in the tail-flick, hot-plate, and formalin tests, respectively. The effects of oxotremorine and epibatidine were blocked by atropine and mecamylamine, respectively. In all three nociceptive tests, naloxone in combination with oxotremorine or epibatidine enhanced the antinociceptive effects of the drugs. The present study demonstrated that stimulation of muscarinic and nicotinic receptors produces antinociceptive effects in the naked-mole rat. The reversal effect of atropine and mecamylamine suggests that this effect is mediated by cholinergic receptors. As naloxone increases the antinociceptive effects of cholinergic agonists, it is suggested that the cholinergic antinociception acts via a gateway facilitated by opioid receptor blockage; however, the precise interaction between these receptor systems needs further investigation.

  11. Assessment of Uncertainties for the NIST 1016 mm Guarded-Hot-Plate Apparatus: Extended Analysis for Low-Density Fibrous-Glass Thermal Insulation.

    PubMed

    Zarr, Robert R

    2010-01-01

    An assessment of uncertainties for the National Institute of Standards and Technology (NIST) 1016 mm Guarded-Hot-Plate apparatus is presented. The uncertainties are reported in a format consistent with current NIST policy on the expression of measurement uncertainty. The report describes a procedure for determination of component uncertainties for thermal conductivity and thermal resistance for the apparatus under operation in either the double-sided or single-sided mode of operation. An extensive example for computation of uncertainties for the single-sided mode of operation is provided for a low-density fibrous-glass blanket thermal insulation. For this material, the relative expanded uncertainty for thermal resistance increases from 1 % for a thickness of 25.4 mm to 3 % for a thickness of 228.6 mm. Although these uncertainties have been developed for a particular insulation material, the procedure and, to a lesser extent, the results are applicable to other insulation materials measured at a mean temperature close to 297 K (23.9 °C, 75 °F). The analysis identifies dominant components of uncertainty and, thus, potential areas for future improvement in the measurement process. For the NIST 1016 mm Guarded-Hot-Plate apparatus, considerable improvement, especially at higher values of thermal resistance, may be realized by developing better control strategies for guarding that include better measurement techniques for the guard gap thermopile voltage and the temperature sensors.

  12. TPSLVM: a dimensionality reduction algorithm based on thin plate splines.

    PubMed

    Jiang, Xinwei; Gao, Junbin; Wang, Tianjiang; Shi, Daming

    2014-10-01

    Dimensionality reduction (DR) has been considered as one of the most significant tools for data analysis. One type of DR algorithms is based on latent variable models (LVM). LVM-based models can handle the preimage problem easily. In this paper we propose a new LVM-based DR model, named thin plate spline latent variable model (TPSLVM). Compared to the well-known Gaussian process latent variable model (GPLVM), our proposed TPSLVM is more powerful especially when the dimensionality of the latent space is low. Also, TPSLVM is robust to shift and rotation. This paper investigates two extensions of TPSLVM, i.e., the back-constrained TPSLVM (BC-TPSLVM) and TPSLVM with dynamics (TPSLVM-DM) as well as their combination BC-TPSLVM-DM. Experimental results show that TPSLVM and its extensions provide better data visualization and more efficient dimensionality reduction compared to PCA, GPLVM, ISOMAP, etc.

  13. The ERESE Project: Modeling Inquiry-Based Plate Tectonic Lessons

    NASA Astrophysics Data System (ADS)

    Symons, C. M.; Helly, M.; Helly, J.; Miller, S. P.; Staudigel, H.; Koppers, A.

    2004-12-01

    The Enduring Resources for Earth Science Education (ERESE) project is a collaborative effort between earth scientists, educators, librarians and data archive managers. Its goal is to develop and maintain a persistent online research and education archive in a digital library environment that supports earth science education in plate tectonics. A key to the library's effectiveness as an educational tool is the efficiency with which educators can access, use and contribute to the library. We have created a master template that educators use to develop inquiry-based curriculum. The central components of the master template include a teacher log, a student log and resource matrices. The teacher's log is divided into stages that reflect our approach to inquiry. This approach was used during a workshop as scientists worked with the teachers to model a reasonable pedagogical analog to scientific inquiry. The student log is similar in structure to a scientific method lab report. There are currently 17 resource matrices that directly access canonical education objects in the digital library, 3 of which relate to expedition planning and 14 to plate tectonics. The structure of the resource matrices allows teachers and students to traverse manageable packets of information relating to a specific topic by expert level (rows) and information type (columns). Teachers download and customize the master template using any web composer and are then invited to upload their lessons through a simple interface at Earthref.org. Once uploaded the lessons become part of the ERESE digital library collection. The upload process allows teachers to define keywords and metadata to allow useful searches by topic, concept or educational standard. The use of a single master template for inquiry lesson design means library contributions will share a common format as well as exploit identical plate tectonic resources.

  14. Development Of Hot Surface Polysilicon-Based Chemical Sensor And Actuator With Integrated Catalytic Micropatterns For Gas Sensing Applications

    NASA Astrophysics Data System (ADS)

    Vereshchagina, E.; Gardeniers, J. G. E.

    2009-05-01

    Over the last twenty years, we have followed a rapid expansion in the development of chemical sensors and microreactors for detection and analysis of volatile organic compounds. However, for many of the developed gas sensors poor sensitivity and selectivity, and high-power consumption remain among one of the main drawbacks. One promising approach to increase selectivity at lower power consumption is calorimetric sensing, performed in a pulsed regime and using specific catalytic materials. In this work, we study kinetics of various catalytic oxidation reactions using micromachined hot surface polysilicon-based sensor containing sensitive and selective catalysts. The sensor acts as both thermal actuator of chemical and biochemical reactions on hot-surfaces and detector of heats (enthalpies) associated with these reactions. Using novel deposition techniques we integrated selective catalysts in an array of hot plates such that they can be thermally actuated and sensed individually. This allows selective detection and analysis of dangerous gas compounds in a mixture, specifically hydrocarbons at concentrations down to low ppm level. In this contribution we compare various techniques for the local immobilization of catalytic material on hot spots of the sensor in terms of process compatibility, mechanical stress, stability and cost.

  15. High precision refractometry based on Fresnel diffraction from phase plates.

    PubMed

    Tavassoly, M Taghi; Naraghi, Roxana Rezvani; Nahal, Arashmid; Hassani, Khosrow

    2012-05-01

    When a transparent plane-parallel plate is illuminated at a boundary region by a monochromatic parallel beam of light, Fresnel diffraction occurs because of the abrupt change in phase imposed by the finite change in refractive index at the plate boundary. The visibility of the diffraction fringes varies periodically with changes in incident angle. The visibility period depends on the plate thickness and the refractive indices of the plate and the surrounding medium. Plotting the phase change versus incident angle or counting the visibility repetition in an incident-angle interval provides, for a given plate thickness, the refractive index of the plate very accurately. It is shown here that the refractive index of a plate can be determined without knowing the plate thickness. Therefore, the technique can be utilized for measuring plate thickness with high precision. In addition, by installing a plate with known refractive index in a rectangular cell filled with a liquid and following the described procedures, the refractive index of the liquid is obtained. The technique is applied to measure the refractive indices of a glass slide, distilled water, and ethanol. The potential and merits of the technique are also discussed.

  16. Sensor network based vehicle classification and license plate identification system

    SciTech Connect

    Frigo, Janette Rose; Brennan, Sean M; Rosten, Edward J; Raby, Eric Y; Kulathumani, Vinod K

    2009-01-01

    Typically, for energy efficiency and scalability purposes, sensor networks have been used in the context of environmental and traffic monitoring applications in which operations at the sensor level are not computationally intensive. But increasingly, sensor network applications require data and compute intensive sensors such video cameras and microphones. In this paper, we describe the design and implementation of two such systems: a vehicle classifier based on acoustic signals and a license plate identification system using a camera. The systems are implemented in an energy-efficient manner to the extent possible using commercially available hardware, the Mica motes and the Stargate platform. Our experience in designing these systems leads us to consider an alternate more flexible, modular, low-power mote architecture that uses a combination of FPGAs, specialized embedded processing units and sensor data acquisition systems.

  17. CEMS using hot wet extractive method based on DOAS

    NASA Astrophysics Data System (ADS)

    Sun, Bo; Zhang, Chi; Sun, Changku

    2011-11-01

    A continuous emission monitoring system (CEMS) using hot wet extractive method based on differential optical absorption spectroscopy (DOAS) is designed. The developed system is applied to retrieving the concentration of SO2 and NOx in flue gas on-site. The flue gas is carried along a heated sample line into the sample pool at a constant temperature above the dew point. In this case, the adverse impact of water vapor on measurement accuracy is reduced greatly, and the on-line calibration is implemented. And then the flue gas is discharged from the sample pool after the measuring process is complete. The on-site applicability of the system is enhanced by using Programmable Logic Controller (PLC) to control each valve in the system during the measuring and on-line calibration process. The concentration retrieving method used in the system is based on the partial least squares (PLS) regression nonlinear method. The relationship between the known concentration and the differential absorption feature gathered by the PLS nonlinear method can be figured out after the on-line calibration process. Then the concentration measurement of SO2 and NOx can be easily implemented according to the definite relationship. The concentration retrieving method can identify the information and noise effectively, which improves the measuring accuracy of the system. SO2 with four different concentrations are measured by the system under laboratory conditions. The results proved that the full-scale error of this system is less than 2%FS.

  18. "Hot-wire" microfluidic flowmeter based on a microfiber coupler.

    PubMed

    Yan, Shao-Cheng; Liu, Zeng-Yong; Li, Cheng; Ge, Shi-Jun; Xu, Fei; Lu, Yan-Qing

    2016-12-15

    Using an optical microfiber coupler (MC), we present a microfluidic platform for strong direct or indirect light-liquid interaction by wrapping a MC around a functionalized capillary. The light propagating in the MC and the liquid flowing in the capillary can be combined and divorced smoothly, keeping a long-distance interaction without the conflict of input and output coupling. Using this approach, we experimentally demonstrate a "hot-wire" microfluidic flowmeter based on a gold-integrated helical MC device. The microfluid inside the glass channel takes away the heat, then cools the MC and shifts the resonant wavelength. Due to the long-distance interaction and high temperature sensitivity, the proposed microfluidic flowmeter shows an ultrahigh flow rate sensitivity of 2.183 nm/(μl/s) at a flow rate of 1 μl/s. The minimum detectable change of the flow rate is around 9 nl/s at 1 μl/s.

  19. Validation of the DIFFAL, HPAC and HotSpot Dispersion Models Using the Full-Scale Radiological Dispersal Device (FSRDD) Field Trials Witness Plate Deposition Dataset.

    PubMed

    Purves, Murray; Parkes, David

    2016-05-01

    Three atmospheric dispersion models--DIFFAL, HPAC, and HotSpot--of differing complexities have been validated against the witness plate deposition dataset taken during the Full-Scale Radiological Dispersal Device (FSRDD) Field Trials. The small-scale nature of these trials in comparison to many other historical radiological dispersion trials provides a unique opportunity to evaluate the near-field performance of the models considered. This paper performs validation of these models using two graphical methods of comparison: deposition contour plots and hotline profile graphs. All of the models tested are assessed to perform well, especially considering that previous model developments and validations have been focused on larger-scale scenarios. Of the models, HPAC generally produced the most accurate results, especially at locations within ∼100 m of GZ. Features present within the observed data, such as hot spots, were not well modeled by any of the codes considered. Additionally, it was found that an increase in the complexity of the meteorological data input to the models did not necessarily lead to an improvement in model accuracy; this is potentially due to the small-scale nature of the trials.

  20. Methods for testing Zernike phase plates and a report on silicon-based phase plates with reduced charging and improved ageing characteristics.

    PubMed

    Marko, Michael; Meng, Xing; Hsieh, Chyongere; Roussie, James; Striemer, Christopher

    2013-11-01

    Imaging with Zernike phase plates is increasingly being used in cryo-TEM tomography and cryo-EM single-particle applications. However, rapid ageing of the phase plates, together with the cost and effort in producing them, present serious obstacles to widespread adoption. We are experimenting with phase plates based on silicon chips that have thin windows; such phase plates could be mass-produced and made available at moderate cost. The windows are coated with conductive layers to reduce charging, and this considerably extends the useful life of the phase plates compared to traditional pure-carbon phase plates. However, a compromise must be reached between robustness and transmission through the phase-plate film. Details are given on testing phase-plate performance by means of imaging an amorphous thin film and evaluating the power spectra of the images.

  1. Methods for testing Zernike phase plates and a report on silicon-based phase plates with reduced charging and improved ageing characteristics

    PubMed Central

    Marko, Michael; Meng, Xing; Hsieh, Chyongere; Roussie, James; Striemer, Christopher

    2013-01-01

    Imaging with Zernike phase plates is increasingly being used in cryo-TEM tomography and cryo-EM single-particle applications. However, rapid ageing of the phase plates, together with the cost and effort in producing them, present serious obstacles to widespread adoption. We are experimenting with phase plates based on silicon chips that have thin windows; such phase plates could be mass-produced and made available at moderate cost. The windows are coated with conductive layers to reduce charging, and this considerably extends the useful life of the phase plates compared to traditional pure-carbon phase plates. However, a compromise must be reached between robustness and transmission through the phase-plate film. Details are given on testing phase-plate performance by means of imaging an amorphous thin film and evaluating the power spectra of the images. PMID:23994351

  2. The parameterization of microchannel-plate-based detection systems

    NASA Astrophysics Data System (ADS)

    Gershman, Daniel J.; Gliese, Ulrik; Dorelli, John C.; Avanov, Levon A.; Barrie, Alexander C.; Chornay, Dennis J.; MacDonald, Elizabeth A.; Holland, Matthew P.; Giles, Barbara L.; Pollock, Craig J.

    2016-10-01

    The most common instrument for low-energy plasmas consists of a top-hat electrostatic analyzer (ESA) geometry coupled with a microchannel-plate-based (MCP-based) detection system. While the electrostatic optics for such sensors are readily simulated and parameterized during the laboratory calibration process, the detection system is often less well characterized. Here we develop a comprehensive mathematical description of particle detection systems. As a function of instrument azimuthal angle, we parameterize (1) particle scattering within the ESA and at the surface of the MCP, (2) the probability distribution of MCP gain for an incident particle, (3) electron charge cloud spreading between the MCP and anode board, and (4) capacitive coupling between adjacent discrete anodes. Using the Dual Electron Spectrometers on the Fast Plasma Investigation on NASA's Magnetospheric Multiscale mission as an example, we demonstrate a method for extracting these fundamental detection system parameters from laboratory calibration. We further show that parameters that will evolve in flight, namely, MCP gain, can be determined through application of this model to specifically tailored in-flight calibration activities. This methodology provides a robust characterization of sensor suite performance throughout mission lifetime. The model developed in this work is not only applicable to existing sensors but also can be used as an analytical design tool for future particle instrumentation.

  3. The Earth's Hot Spots.

    ERIC Educational Resources Information Center

    Vink, Gregory E.; And Others

    1985-01-01

    Hot spots are isolated areas of geologic activity where volcanic eruptions, earthquakes, and upwelling currents occur far from plate boundaries. These mantle plumes are relatively stable and crustal plates drift over them. The nature and location of hot spots (with particular attention to the Hawaiian Islands and Iceland) are discussed. (DH)

  4. Dual-mode operation of 2D material-base hot electron transistors.

    PubMed

    Lan, Yann-Wen; Torres, Carlos M; Zhu, Xiaodan; Qasem, Hussam; Adleman, James R; Lerner, Mitchell B; Tsai, Shin-Hung; Shi, Yumeng; Li, Lain-Jong; Yeh, Wen-Kuan; Wang, Kang L

    2016-09-01

    Vertical hot electron transistors incorporating atomically-thin 2D materials, such as graphene or MoS2, in the base region have been proposed and demonstrated in the development of electronic and optoelectronic applications. To the best of our knowledge, all previous 2D material-base hot electron transistors only considered applying a positive collector-base potential (VCB > 0) as is necessary for the typical unipolar hot-electron transistor behavior. Here we demonstrate a novel functionality, specifically a dual-mode operation, in our 2D material-base hot electron transistors (e.g. with either graphene or MoS2 in the base region) with the application of a negative collector-base potential (VCB < 0). That is, our 2D material-base hot electron transistors can operate in either a hot-electron or a reverse-current dominating mode depending upon the particular polarity of VCB. Furthermore, these devices operate at room temperature and their current gains can be dynamically tuned by varying VCB. We anticipate our multi-functional dual-mode transistors will pave the way towards the realization of novel flexible 2D material-based high-density and low-energy hot-carrier electronic applications.

  5. Dual-mode operation of 2D material-base hot electron transistors

    PubMed Central

    Lan, Yann-Wen; Torres, Jr., Carlos M.; Zhu, Xiaodan; Qasem, Hussam; Adleman, James R.; Lerner, Mitchell B.; Tsai, Shin-Hung; Shi, Yumeng; Li, Lain-Jong; Yeh, Wen-Kuan; Wang, Kang L.

    2016-01-01

    Vertical hot electron transistors incorporating atomically-thin 2D materials, such as graphene or MoS2, in the base region have been proposed and demonstrated in the development of electronic and optoelectronic applications. To the best of our knowledge, all previous 2D material-base hot electron transistors only considered applying a positive collector-base potential (VCB > 0) as is necessary for the typical unipolar hot-electron transistor behavior. Here we demonstrate a novel functionality, specifically a dual-mode operation, in our 2D material-base hot electron transistors (e.g. with either graphene or MoS2 in the base region) with the application of a negative collector-base potential (VCB < 0). That is, our 2D material-base hot electron transistors can operate in either a hot-electron or a reverse-current dominating mode depending upon the particular polarity of VCB. Furthermore, these devices operate at room temperature and their current gains can be dynamically tuned by varying VCB. We anticipate our multi-functional dual-mode transistors will pave the way towards the realization of novel flexible 2D material-based high-density and low-energy hot-carrier electronic applications. PMID:27581550

  6. Dual-mode operation of 2D material-base hot electron transistors

    NASA Astrophysics Data System (ADS)

    Lan, Yann-Wen; Torres, Carlos M., Jr.; Zhu, Xiaodan; Qasem, Hussam; Adleman, James R.; Lerner, Mitchell B.; Tsai, Shin-Hung; Shi, Yumeng; Li, Lain-Jong; Yeh, Wen-Kuan; Wang, Kang L.

    2016-09-01

    Vertical hot electron transistors incorporating atomically-thin 2D materials, such as graphene or MoS2, in the base region have been proposed and demonstrated in the development of electronic and optoelectronic applications. To the best of our knowledge, all previous 2D material-base hot electron transistors only considered applying a positive collector-base potential (VCB > 0) as is necessary for the typical unipolar hot-electron transistor behavior. Here we demonstrate a novel functionality, specifically a dual-mode operation, in our 2D material-base hot electron transistors (e.g. with either graphene or MoS2 in the base region) with the application of a negative collector-base potential (VCB < 0). That is, our 2D material-base hot electron transistors can operate in either a hot-electron or a reverse-current dominating mode depending upon the particular polarity of VCB. Furthermore, these devices operate at room temperature and their current gains can be dynamically tuned by varying VCB. We anticipate our multi-functional dual-mode transistors will pave the way towards the realization of novel flexible 2D material-based high-density and low-energy hot-carrier electronic applications.

  7. TYPICAL HOT WATER DRAW PATTERNS BASED ON FIELD DATA

    SciTech Connect

    Lutz, Jim; Melody, Moya

    2012-11-08

    There is significant variation in hot water use and draw patterns among households. This report describes typical hot water use patterns in single-family residences in North America. We found that daily hot water use is highly variable both among residences and within the same residence. We compared the results of our analysis of the field data to the conditions and draw patterns established in the current U.S. Department of Energy (DOE) test procedure for residential water heaters. The results show a higher number of smaller draws at lower flow rates than used in the test procedure. The data from which the draw patterns were developed were obtained from 12 separate field studies. This report describes the ways in which we managed, cleaned, and analyzed the data and the results of our data analysis. After preparing the data, we used the complete data set to analyze inlet and outlet water temperatures. Then we divided the data into three clusters reflecting house configurations that demonstrated small, medium, or large median daily hot water use. We developed the three clusters partly to reflect efforts of the ASHRAE standard project committee (SPC) 118.2 to revise the test procedure for residential water heaters to incorporate a range of draw patterns. ASHRAE SPC 118.2 has identified the need to separately evaluate at least three, and perhaps as many as five, different water heater capacities. We analyzed the daily hot water use data within each cluster in terms of volume and number of hot water draws. The daily draw patterns in each cluster were characterized using distributions for volume of draws, duration of draws, time since previous draw, and flow rates.

  8. Optical waveguide spectrometer based on thin-film glass plates.

    PubMed

    Qi, Zhi-Mei; Matsuda, Naoki; Yoshida, Takamitsu; Asano, Hajime; Takatsu, Akiko; Kato, Kenji

    2002-11-15

    Commercially available thin-film glass plates have been successfully used for optical waveguide spectroscopy of chemical and biological films adsorbed upon the plates' surfaces. A 50-mum -thick glass plate was placed in contact with two parallel strips of silicone rubber supported on a slide glass. The plate area between the rubber strips served as the waveguiding region, eliminating the negative effect of the substrate on absorbance sensitivity. We coupled white light into the waveguide by focusing the light from a xenon lamp onto one end of a glass fiber and then inserting the other end into a glycerol drop overlaid upon the plate's surface. With a CCD detector, light at wavelengths as short as 360 nm was found to transmit out of the plate's end face. The propagation loss of the waveguide was measured to be

  9. Rigorous assessment and integration of the sequence and structure based features to predict hot spots

    PubMed Central

    2011-01-01

    Background Systematic mutagenesis studies have shown that only a few interface residues termed hot spots contribute significantly to the binding free energy of protein-protein interactions. Therefore, hot spots prediction becomes increasingly important for well understanding the essence of proteins interactions and helping narrow down the search space for drug design. Currently many computational methods have been developed by proposing different features. However comparative assessment of these features and furthermore effective and accurate methods are still in pressing need. Results In this study, we first comprehensively collect the features to discriminate hot spots and non-hot spots and analyze their distributions. We find that hot spots have lower relASA and larger relative change in ASA, suggesting hot spots tend to be protected from bulk solvent. In addition, hot spots have more contacts including hydrogen bonds, salt bridges, and atomic contacts, which favor complexes formation. Interestingly, we find that conservation score and sequence entropy are not significantly different between hot spots and non-hot spots in Ab+ dataset (all complexes). While in Ab- dataset (antigen-antibody complexes are excluded), there are significant differences in two features between hot pots and non-hot spots. Secondly, we explore the predictive ability for each feature and the combinations of features by support vector machines (SVMs). The results indicate that sequence-based feature outperforms other combinations of features with reasonable accuracy, with a precision of 0.69, a recall of 0.68, an F1 score of 0.68, and an AUC of 0.68 on independent test set. Compared with other machine learning methods and two energy-based approaches, our approach achieves the best performance. Moreover, we demonstrate the applicability of our method to predict hot spots of two protein complexes. Conclusion Experimental results show that support vector machine classifiers are quite

  10. Recognition of blurred license plate of vehicle based on natural image matting

    NASA Astrophysics Data System (ADS)

    Liang, Fangfang; Liu, Yong; Yao, Gang

    2009-10-01

    Car's license plate identification system based on image processing is one of the key technologies of intelligent transportation system. In most cases, license plate numbers can be accurately recognized by the generic identification systems while the image is clear. However, sometime the license plate are seriously blurred by some dunghill such as mud or water smoke before camera lens, which is hard to be identified. In order to get higher recognition rate of blurred license plate, an approach based on natural image matting is proposed in this paper.

  11. Hot film anemometry. Citations from the NTIS data base

    NASA Astrophysics Data System (ADS)

    Habercom, G. E., Jr.

    1980-08-01

    The principles of hot film anemometer operation are summarized; wind tunnel and laboratory tests are described; flow field dynamics are discussed involving turbulence, boundary layers, separation, shock waves, and stresses; mathematical models and analysis are presented; computer techniques are outlined; and a number of applications are given. This updated bibliography contains 58 citations, 3 of which are new entries to the previous edition.

  12. Dynamic programming-based hot spot identification approach for pedestrian crashes.

    PubMed

    Medury, Aditya; Grembek, Offer

    2016-08-01

    Network screening techniques are widely used by state agencies to identify locations with high collision concentration, also referred to as hot spots. However, most of the research in this regard has focused on identifying highway segments that are of concern to automobile collisions. In comparison, pedestrian hot spot detection has typically focused on analyzing pedestrian crashes in specific locations, such as at/near intersections, mid-blocks, and/or other crossings, as opposed to long stretches of roadway. In this context, the efficiency of the some of the widely used network screening methods has not been tested. Hence, in order to address this issue, a dynamic programming-based hot spot identification approach is proposed which provides efficient hot spot definitions for pedestrian crashes. The proposed approach is compared with the sliding window method and an intersection buffer-based approach. The results reveal that the dynamic programming method generates more hot spots with a higher number of crashes, while providing small hot spot segment lengths. In comparison, the sliding window method is shown to suffer from shortcomings due to a first-come-first-serve approach vis-à-vis hot spot identification and a fixed hot spot window length assumption.

  13. Effects of selected cooking procedures on the survival of Escherichia coli O157:H7 in inoculated steaks cooked on a hot plate or gas barbecue grill.

    PubMed

    Gill, C O; Devos, J; Youssef, M K; Yang, X

    2014-06-01

    Beef steaks (2 cm thick) were each inoculated at three sites in the central plane with Escherichia coli O157:H7 at 5.9 ± 0.3 log CFU per site. Temperatures at steak centers were monitored during cooking on a hot plate or the grill of a gas barbeque. Steaks were cooked in groups of five using the same procedures and cooking each steak to the same temperature, and surviving E. coli O157:H7 at each site was enumerated. When steaks cooked on the hot plate were turned over every 2 or 4 min during cooking to between 56 and 62°C, no E. coli O157:H7 was recovered from steaks cooked to ≥58 or 62°C, respectively. When steaks were cooked to ≤71°C and turned over once during cooking, E. coli O157:H7 was recovered from steaks in groups turned over after ≤8 min but not from steaks turned over after 10 or 12 min. E. coli O157:H7 was recovered in similar numbers from steaks that were not held or were held for 3 min after cooking when steaks were turned over once after 4 or 6 min during cooking. When steaks were cooked on the grill with the barbeque lid open and turned over every 2 or 4 min during cooking to 63 or 56°C, E. coli O157:H7 was recovered from only those steaks turned over at 4-min intervals and cooked to 56°C. E. coli O157:H7 was recovered from some steaks turned over once during cooking on the grill and held or not held after cooking to 63°C. E. coli O157:H7 was not recovered from steaks turned over after 4 min during cooking to 60°C on the grill with the barbeque lid closed or when the lid was closed after 6 min. Apparently, the microbiological safety of mechanically tenderized steaks can be assured by turning steaks over at intervals of about 2 min during cooking to ≥60°C in an open skillet or on a barbecue grill. When steaks are turned over only once during cooking to ≥60°C, microbiological safety may be assured by covering the skillet or grill with a lid during at least the final minutes of cooking.

  14. Tectonic Plate Parameters Estimated in the International Terrestrial Reference Frame ITRF2008 Based on SLR Stations

    NASA Astrophysics Data System (ADS)

    Kraszewska, Katarzyna; Jagoda, Marcin; Rutkowska, Miłosława

    2016-10-01

    This paper concerns an analysis of the accuracy of estimated parameters Ω (Φ, Λ, ω) which define the tectonic plate motions. The study is based on the velocities of station positions published by ITRF2008 for Satellite Laser Ranging (SLR) technique. The Eurasian, African, North American and Australian plates were used in the analysis. Influence of the number and location of stations on the plate surface on estimation accuracy of the tectonic plate motion parameters was discussed. The results were compared with the APKIM 2005 IGN model. In general, a remarkable concurrence agreement between our solutions and the APKIM 2005 model was found.

  15. Microstructural anomalies in hot-isostatic pressed U–10wt.% Mo fuel plates with Zr diffusion barrier

    SciTech Connect

    Park, Y.; Eriksson, N.; Keiser, D. D.; Jue, J.; Rabin, B.; Moore, G.; Sohn, Y. H.

    2015-05-01

    Microstructural anomalies in the co-rolled-and-HIP'ed U–10 wt.% Mo (U10Mo) metallic fuel plate with Zr diffusion barrier assembly were examined as a function of HIP temperature (from 520 to 580 °C) and duration (45, 60, 90, 180 and 345 min) by scanning and transmission electron microscopy. The anomalies observed in this study are carbide/oxide inclusions within the U10Mo fuel alloy, and regions of limited interaction between the U10Mo alloy and Zr barrier, frequently associated with carbide/oxide inclusions. In the U10Mo alloy, the cF8, Fm3m (225) UC phase (a=4.955 Å) and cF12, Fm3m (225) UO2 phase (a=5.467 Å) were observed throughout the U10Mo alloy with an approximate volume percent of 0.5 to 1.8. The volume percent of the UC–UO2 inclusions within the U10Mo alloy did not change as functions of HIP temperature and time. These inclusion phases, located near the surface of the U10Mo alloy, were frequently observed to impede the development of interdiffusion and reaction between the U10Mo alloy and Zr diffusion barrier. The regions of limited interaction between the U10Mo and Zr barrier decreased with an increase in HIP temperature, however no noticeable trend was observed with an increase in HIP duration at constant temperature of 560 °C.

  16. Growth kinetics and microstructural evolution during hot isostatic pressing of U-10 wt.% Mo monolithic fuel plate in AA6061 cladding with Zr diffusion barrier

    SciTech Connect

    Y. Park; J. Yoo; K. Huang; D. D. Keiser, Jr.; J. F. Jue; B. Rabin; G. Moore; Y. H. Sohn

    2014-04-01

    Phase constituents and microstructure changes in RERTR fuel plate assemblies as functions of temperature and duration of hot-isostatic pressing (HIP) during fabrication were examined. The HIP process was carried out as functions of temperature (520, 540, 560 and 580 °C for 90 min) and time (45–345 min at 560 °C) to bond 6061 Al-alloy to the Zr diffusion barrier that had been co-rolled with U-10 wt.% Mo (U10Mo) fuel monolith prior to the HIP process. Scanning and transmission electron microscopies were employed to examine the phase constituents, microstructure and layer thickness of interaction products from interdiffusion. At the interface between the U10Mo and Zr, following the co-rolling, the UZr2 phase was observed to develop adjacent to Zr, and the a-U phase was found between the UZr2 and U10Mo, while the Mo2Zr was found as precipitates mostly within the a-U phase. The phase constituents and thickness of the interaction layer at the U10Mo-Zr interface remained unchanged regardless of HIP processing variation. Observable growth due to HIP was only observed for the (Al,Si)3Zr phase found at the Zr/AA6061 interface, however, with a large activation energy of 457 ± 28 kJ/mole. Thus, HIP can be carried to improve the adhesion quality of fuel plate without concern for the excessive growth of the interaction layer, particularly at the U10Mo-Zr interface with the a-U, Mo2Zr, and UZr2 phases.

  17. A seismic reflection image for the base of a tectonic plate.

    PubMed

    Stern, T A; Henrys, S A; Okaya, D; Louie, J N; Savage, M K; Lamb, S; Sato, H; Sutherland, R; Iwasaki, T

    2015-02-05

    Plate tectonics successfully describes the surface of Earth as a mosaic of moving lithospheric plates. But it is not clear what happens at the base of the plates, the lithosphere-asthenosphere boundary (LAB). The LAB has been well imaged with converted teleseismic waves, whose 10-40-kilometre wavelength controls the structural resolution. Here we use explosion-generated seismic waves (of about 0.5-kilometre wavelength) to form a high-resolution image for the base of an oceanic plate that is subducting beneath North Island, New Zealand. Our 80-kilometre-wide image is based on P-wave reflections and shows an approximately 15° dipping, abrupt, seismic wave-speed transition (less than 1 kilometre thick) at a depth of about 100 kilometres. The boundary is parallel to the top of the plate and seismic attributes indicate a P-wave speed decrease of at least 8 ± 3 per cent across it. A parallel reflection event approximately 10 kilometres deeper shows that the decrease in P-wave speed is confined to a channel at the base of the plate, which we interpret as a sheared zone of ponded partial melts or volatiles. This is independent, high-resolution evidence for a low-viscosity channel at the LAB that decouples plates from mantle flow beneath, and allows plate tectonics to work.

  18. A Study of Fatigue Crack Propagation in Powder Metallurgy Hot Isotatically Pressed Nickel-Base Alloy.

    DTIC Science & Technology

    1984-01-31

    GR. Fatigue crack propagation, nickel-based superalloys, powder metallurgy, HIP , grain size influence t3ABSRACT (Continue on everse if neceaaary and...AD-A13L9290 ’A STUDY OF FATIGUE CRACK PROPAGATION IN POWDER METALLURGY HOT SOTATCAL.U) LEHIGHUNIVBETHEHEM PA DEPT 0F METALLURGY AND MATERIALS ENG...ClaaaficatioA Study of Fatigue Crack Propagation in Powder Metallurgy Hot Iso tatically Pressed Nickel-Base Alloy 12. PERSONAL AUTHOR(S) (Unclassified

  19. Plate Tectonics Constrained by Evidence-Based Magmatic Temperatures and Phase Relations of Fertile Lherzolite (Invited)

    NASA Astrophysics Data System (ADS)

    Green, D. H.; Falloon, T.

    2010-12-01

    In order to understand Earth’s plate tectonics we must interpret the most direct probes for mantle composition and temperature distribution i.e. the primitive basaltic magmas and peridotites representing partial melts and mantle residues. An evidence-based approach to identification of parental magmas and determination of their temperatures requires glass and phenocryst compositions and experimentally calibrated Fe/Mg partitioning between olivine and melt. We have compared magmatic crystallization temperatures between ‘hot-spot’(proposed to be plume-related) and normal mid-ocean ridge basalt (MORB) parental liquids, by examining three representative magmatic suites from both ocean island (Hawaii, Iceland, and Réunion) and mid-ocean ridge settings (Cocos-Nazca, East Pacific Rise, and Mid-Atlantic Ridge). We have glass and olivine phenocryst compositions, including volatile (H2O) contents, and have calculated parental liquid compositions at 0.2GPa by incrementally adding olivine back into the glass compositions until a liquid in equilibrium with the most-magnesian olivine phenocryst composition is obtained. The results of these calculations demonstrate that there is very little difference (maximum of ~20°C) between the ranges of crystallization temperatures of the parental liquids (MORB:1243-1351°C versus OIB:1286-1372°C) when volatile contents are taken into account. However while lacking temperature contrast, the source regions for ‘hot-spot’ parental magmas contain geochemical signatures of old subducted crust/lithosphere. The mantle depths of origin determined for both the MORB and OIB suites are similar (MORB:1-2 GPa; OIB:1-2.5 GPa). Calculations of mantle potential temperatures (Tp) are model dependent, particularly to melt fraction from an inferred source. Assuming similar fertile lherzolite sources, the differences in Tp values between the hottest MORB and the hottest ocean island tholeiite sources are ~80°C. These differences disappear if the

  20. Developing a Basal Texture with Two Peaks Tilting Towards the Transverse Direction in Hot Rolled Mg-5.7Zn-0.5Zr Plates

    NASA Astrophysics Data System (ADS)

    Wang, Yannan; Xin, Yunchang; Chapuis, Adrien; Yu, Huihui; Liu, Qing

    2016-08-01

    Rolled Mg alloys often present a basal texture with the (0002) poles slightly tilting from the normal direction (ND) towards the rolling direction. The current work systematically studies the formation of a double-peaked basal texture tilting from the ND towards the transverse direction (TD) of Mg-5.7Zn-0.5Zr (ZK60) plates hot rolled from the as-cast condition. Our results show that a basal texture forms with the two peaks obviously tilting from the ND towards the TD after rolling to reductions over 19 pct at 673 K (400 °C), but does not appear after rolling at 293 K (20 °C). The TD-tilted double peaks of basal poles disappear after annealing, developing a stronger peak of basal poles around the ND. The microstructural examination indicates that this TD-tilted basal texture mainly results from rolling deformation rather than dynamic recrystallization. Crystal plasticity simulation using the VPSC model was used to understand the effect of slips and twinning on the formation of this TD-tilted basal texture. Simulation demonstrates that, compared to prismatic slip, pyramidal slip is more efficient to generate the basal texture tilting towards the TD. The possible mechanisms affecting the activity of non-basal slips are discussed.

  1. Hot plate annealing at a low temperature of a thin ferroelectric P(VDF-TrFE) film with an improved crystalline structure for sensors and actuators.

    PubMed

    Mahdi, Rahman Ismael; Gan, W C; Abd Majid, W H

    2014-10-14

    Ferroelectric poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) copolymer 70/30 thin films are prepared by spin coating. The crystalline structure of these films is investigated by varying the annealing temperature from the ferroelectric phase to the paraelectric phase. A hot plate was used to produce a direct and an efficient annealing effect on the thin film. The dielectric, ferroelectric and pyroelectric properties of the P(VDF-TrFE) thin films are measured as a function of different annealing temperatures (80 to 140 °C). It was found that an annealing temperature of 100 °C (slightly above the Curie temperature, Tc) has induced a highly crystalline β phase with a rod-like crystal structure, as examined by X-ray. Such a crystal structure yields a high remanent polarization, Pr = 94 mC/m2, and pyroelectric constant, p = 24 μC/m2K. A higher annealing temperature exhibits an elongated needle-like crystal domain, resulting in a decrease in the crystalline structure and the functional electrical properties. This study revealed that highly crystalline P(VDF-TrFE) thin films could be induced at 100 °C by annealing the thin film with a simple and cheap method.

  2. Prediction of protein interaction hot spots using rough set-based multiple criteria linear programming.

    PubMed

    Chen, Ruoying; Zhang, Zhiwang; Wu, Di; Zhang, Peng; Zhang, Xinyang; Wang, Yong; Shi, Yong

    2011-01-21

    Protein-protein interactions are fundamentally important in many biological processes and it is in pressing need to understand the principles of protein-protein interactions. Mutagenesis studies have found that only a small fraction of surface residues, known as hot spots, are responsible for the physical binding in protein complexes. However, revealing hot spots by mutagenesis experiments are usually time consuming and expensive. In order to complement the experimental efforts, we propose a new computational approach in this paper to predict hot spots. Our method, Rough Set-based Multiple Criteria Linear Programming (RS-MCLP), integrates rough sets theory and multiple criteria linear programming to choose dominant features and computationally predict hot spots. Our approach is benchmarked by a dataset of 904 alanine-mutated residues and the results show that our RS-MCLP method performs better than other methods, e.g., MCLP, Decision Tree, Bayes Net, and the existing HotSprint database. In addition, we reveal several biological insights based on our analysis. We find that four features (the change of accessible surface area, percentage of the change of accessible surface area, size of a residue, and atomic contacts) are critical in predicting hot spots. Furthermore, we find that three residues (Tyr, Trp, and Phe) are abundant in hot spots through analyzing the distribution of amino acids.

  3. Theoretical analysis based on fundamental functions of thin plate and experimental measurement for vibration characteristics of a plate coupled with liquid

    NASA Astrophysics Data System (ADS)

    Liao, Chan-Yi; Wu, Yi-Chuang; Chang, Ching-Yuan; Ma, Chien-Ching

    2017-04-01

    This study combined theoretical, experimental, and numerical analysis to investigate the vibration characteristics of a thin rectangular plate positioned horizontally at the bottom of a rectangular container filled with liquid. Flow field pressure was derived using an equation governing the behavior of incompressible fluids. Analytic solutions to vibrations in a thin plate in air served as the fundamental function of the thin plate coupled with liquid. We then used liquid pressure, and the out-of-plane deflection of the thin plate for the construction of frequency response functions for the analysis of vibration characteristics in the liquid-plate coupling system. Two experimental methods were employed to measure the vibration characteristics of the thin plate immersed in water. The first involved using sensors of polyvinylidene difluoride (PVDF) to measure transient signals of fluid-plate system subjected an impact at the thin plate. These were then converted to the frequency domain in order to obtain the resonant frequencies of the fluid-plate coupling system. The second method was amplitude-fluctuation electronic speckle pattern interferometry (AF-ESPI), which was used to measure the dynamic characteristics of the thin plate in the flow field. This method was paired with the image processing techniques, temporal speckle pattern interferometry (TSPI) and temporal standard deviation (TSTD), to obtain clear mode shapes of the thin plate and resonant frequencies. Comparison of the results from theoretical analysis, finite element method, and experimental measurements confirmed the accuracy of our theoretical analysis, which was superior to the conventional approach based on beam mode shape functions. The experimental methods proposed in this study can be used to measure the resonant frequencies of underwater thin plates, and clear mode shapes can be obtained using AF-ESPI. Our results indicate that the resonant frequencies of thin plates underwater are lower than

  4. Numerical calculation of the operation wavelength range of a polarization controller based on rotatable wave plates

    NASA Astrophysics Data System (ADS)

    Park, Hee Su; Sharma, Aditya

    2016-12-01

    We calculate the operation wavelength range of polarization controllers based on rotating wave plates such as paddle-type optical fiber devices. The coverages over arbitrary polarization conversion or arbitrary birefringence compensation are numerically estimated. The results present the acceptable phase retardation range of polarization controllers composed of two quarter-wave plates or a quarter-half-quarter-wave plate combination, and thereby determines the operation wavelength range of a given design. We further prove that a quarter-quarter-half-wave-plate combination is also an arbitrary birefringence compensator as well as a conventional quarter-half-quarter-wave-plate combination, and show that the two configurations have the identical range of acceptable phase retardance within the uncertainty of our numerical method.

  5. Multifrequency multi-qubit entanglement based on plasmonic hot spots

    PubMed Central

    Ren, Jun; Wu, Tong; Zhang, Xiangdong

    2015-01-01

    The theoretical method to study strong coupling between an ensemble of quantum emitters (QEs) and surface plasmons excited by the nanoparticle cluster has been presented by using a rigorous first-principles electromagnetic Green’s tensor technique. We have demonstrated that multi-qubit entanglements for two-level QEs can be produced at different coupling resonance frequencies, when they locate in the hot spots of the metallic nanoparticle cluster. The duration of quantum beats for such an entanglement can reach two orders longer than that for the entanglement in a photonic cavity. The phenomenon originates from collective coupling resonance excitation of the cluster. At the frequency of single scattering resonance, the entanglement cannot be produced although the single QE spontaneous decay rate is very big. PMID:26350051

  6. Multifrequency multi-qubit entanglement based on plasmonic hot spots

    NASA Astrophysics Data System (ADS)

    Ren, Jun; Wu, Tong; Zhang, Xiangdong

    2015-09-01

    The theoretical method to study strong coupling between an ensemble of quantum emitters (QEs) and surface plasmons excited by the nanoparticle cluster has been presented by using a rigorous first-principles electromagnetic Green’s tensor technique. We have demonstrated that multi-qubit entanglements for two-level QEs can be produced at different coupling resonance frequencies, when they locate in the hot spots of the metallic nanoparticle cluster. The duration of quantum beats for such an entanglement can reach two orders longer than that for the entanglement in a photonic cavity. The phenomenon originates from collective coupling resonance excitation of the cluster. At the frequency of single scattering resonance, the entanglement cannot be produced although the single QE spontaneous decay rate is very big.

  7. Plate Tectonics and Taiwan Orogeny based on TAIGER Experiments

    NASA Astrophysics Data System (ADS)

    Wu, F. T.; Kuochen, H.; McIntosh, K. D.

    2014-12-01

    Plate tectonics framework is usually complex in a collision zone, where continental lithosphere is involved. In the young Taiwan orogeny, with geologic understanding and large new geodetic and subsurface datasets now available an environment has been created for testing tectonic hypotheses regarding collision and orogeny. Against the background of the commonly accepted view of Taiwan as a southward propagating, self-similar 2-D orogen, a fully 3-D structure is envisaged. Along the whole length of the island the convergence of the Eurasian plate (EUP) the Philippine Sea plate (PSP) takes shape with different plate configurations. In northern Taiwan the convergence occurs with simultaneous collision of the oceanic PSP with continental EUP and the northward subduction of the PSP; in the south, EUP, in the guise of the South China Sea rifted Eurasian continent, subducts toward the east; in central Taiwan collision of oceanic PSP with continental EUP dominates. When relocated seismicity and focal mechanisms are superposed on subsurface P and Vp/Vs velocity images the configurations and the kinematics of the PSP and EUP collision and subduction become clear. While in northern Taiwan the subduction/collision explains well the high peaks and their dwindling (accompanied by crustal thinning) toward the north. In the south, mountains rise above the east-dipping EUP subduction zone as the Eurasian continental shelf veers toward the southwest, divergent from the trend of the Luzon Arc - calling into question the frequently cited arc-continent collision model of Taiwan orogeny. High velocity anomaly and Benioff seismicity coexist in the south. Going north toward Central Taiwan the high velocity anomaly persists for another 150 km or so, but it becomes seismically quiescent. Above the quiescent section the PSP and EUP collide to build the main part of the Central Range and its parallel neighbor the eastern Coastal Range. Key implications regarding orogeny include: 1) Significant

  8. Enzymic and molecular properties of base-plate parts of bacteriophage P22.

    PubMed

    Iwashita, S; Kanegasaki, S

    1976-05-17

    Using 14C-labeled Salmonella bacterial cells as the substrate, the enzymic and molecular properties of the base-plate parts of phage P22 were studied. The base-plate part consisted of a single protein species which cleaved extensively the O-antigen of Salmonella typhimurium, Salmonelly schottmuellerie and with somewhat slower rate that of Salmonella typhi, releasing oligo-saccharide products with rhamnose at the reducing end. Much less cleavage was observed with a strain of S. typhimurium lysogenic for P22, and no significant reaction with Salmonella anatum, Salmonella newington and Salmonella minneapolis. The base-plate part enzyme was a very heat-stable protein and only 10-20% loss was observed after treatment at 85 degrees C for 5 min. The pH optimum of the enzyme was around 7.5, and the glycosidase activity was not influenced by the ionic strength (25-250 mM( of the medium or the presence of Mg2+. The molecular weight of the base-plate part was 320,000 by sedimentation equilibrium. Dodecylsulphate-acrylamide gel electrophoresis revealed a single band of molecular weight 77,000, indicating that a single base-plate part corresponds to a tetramer of identical subunits. Circular dichroism spectra of P22 base-plate parts showed a major contribution of beta structure. The protein was rich in acidic amino acids, glycine and serine.

  9. Hot Electron-Based Near-Infrared Photodetection Using Bilayer MoS2.

    PubMed

    Wang, Wenyi; Klots, Andrey; Prasai, Dhiraj; Yang, Yuanmu; Bolotin, Kirill I; Valentine, Jason

    2015-11-11

    Recently, there has been much interest in the extraction of hot electrons generated from surface plasmon decay, as this process can be used to achieve additional bandwidth for both photodetectors and photovoltaics. Hot electrons are typically injected into semiconductors over a Schottky barrier between the metal and semiconductor, enabling generation of photocurrent with below bandgap photon illumination. As a two-dimensional semiconductor single and few layer molybdenum disulfide (MoS2) has been demonstrated to exhibit internal photogain and therefore becomes an attractive hot electron acceptor. Here, we investigate hot electron-based photodetection in a device consisting of bilayer MoS2 integrated with a plasmonic antenna array. We demonstrate sub-bandgap photocurrent originating from the injection of hot electrons into MoS2 as well as photoamplification that yields a photogain of 10(5). The large photogain results in a photoresponsivity of 5.2 A/W at 1070 nm, which is far above similar silicon-based hot electron photodetectors in which no photoamplification is present. This technique is expected to have potential use in future ultracompact near-infrared photodetection and optical memory devices.

  10. Hot corrosion testing of Ni-based alloys and coatings in a modified Dean rig

    NASA Astrophysics Data System (ADS)

    Steward, Jason Reid

    Gas turbine blades are designed to withstand a variety of harsh operating conditions. Although material and coating improvements are constantly administered to increase the mean time before turbine refurbishment or replacement, hot corrosion is still considered as the major life-limiting factor in many industrial and marine gas turbines. A modified Dean rig was designed and manufactured at Tennessee Technological University to simulate the accelerated hot corrosion conditions and to conduct screening tests on the new coatings on Ni-based superalloys. Uncoated Ni-based superalloys, Rene 142 and Rene 80, were tested in the modified Dean rig to establish a testing procedure for Type I hot corrosion. The influence of surface treatments on the hot corrosion resistance was then investigated. It was found that grit-blasted specimens showed inferior hot corrosion resistance than that of the polished counterpart. The Dean rig was also used to test model MCrAlY alloys, pack cementation NiAl coatings, and electro-codeposited MCrAlY coatings. Furthermore, the hot corrosion attack on the coated-specimens were also assessed using a statistical analysis approach.

  11. Design and Development of ZigBee Based Instantaneous Flat-plate Collector Efficiency Measurement System

    NASA Astrophysics Data System (ADS)

    Vairamani, K.; Venkatesh, K. Arun; Mathivanan, N.

    2011-01-01

    Computing the efficiency of flat-plate collector is vital in solar thermal system testing. This paper presents the design of ZigBee enabled data acquisition system for instantaneous flat-plate collector efficiency calculation. It involves measurement of parameters like inlet and outlet fluid temperatures, ambient temperature and solar radiation intensity. The designed system has a base station and a sensor node. ZigBee wireless communication protocol is used for communication between the base station and the sensor node for wireless data acquisition. The wireless sensor node which is mounted over the collector plate includes the necessary sensors and associated signal-conditioners. An application program has been developed on LabVIEW platform for data acquisition, processing and analysis and is executed in base station PC. Instantaneous flat-plate collector efficiency is computed and reported.

  12. Computer animation of Phanerozoic plate motions

    SciTech Connect

    Scotese, C.R. . Dept. of Geology)

    1992-01-01

    Since 1985, the PALEOMAP Project, in collaboration with research groups both in the US and abroad, has assembled a digital model that describes global plate motions during the last 600 million years. In this paper the authors present a series of computer animations that dynamically illustrates the movement of continents and terranes, and the evolution of the ocean basins since the breakup of the late Precambrian supercontinent. These animations depict the motion of the plates from both equatorial and polar perspectives. Mesozoic and Cenozoic plate tectonic reconstructions are based on a synthesis of linear magnetic anomalies, fracture zone locations, intracontinental rifts, collision and thrust belts, and zones of strike-slip. Paleozoic plate reconstructions, though more speculative, are based on evidence of past subduction, continental collision, and inferred sea floor spreading. The relative longitudinal positions of the continents during the Paleozoic and the width of intervening oceans have been adjusted to best explain changing biogeographic and paleoclimatic patterns. A new paleomagnetic/hot spot reference frame has been constructed that combines paleomagnetic data compiled by Rob Van der Voo (1992) with inferred motion relative to a fixed frame of hot spots. Using probable Early Mesozoic and Paleozoic hot spot tracks on the major continents, the authors have extended plate motions relative to the hot spot reference frame back to 400 million years.

  13. Collaborative guarded-hot-plate tests between the Laboratoire national de métrologie et d’essais and the National Institute of Standards and Technology

    NASA Astrophysics Data System (ADS)

    Zarr, Robert R.; Guthrie, William F.; Hay, Bruno; Koenen, Alain

    2017-02-01

    A collaborative study to compare the long-term measurement performance between guarded-hot-plate facilities at the Laboratoire national de métrologie et d’essais (LNE) in France and the National Institute of Standards and Technology (NIST) in the United States is presented. Thermal conductivity data were compiled from three international comparisons organized from 1997 to 2014. Measurements were conducted in accordance with standardized test methods (ISO 8302 or ASTM C 177) over a temperature range from 280 K to 320 K. Nine thermal insulating materials (either mineral fiber or expanded polystyrene) were examined covering broad ranges of bulk densities (13 kg · m‑3–200 kg · m‑3) and thicknesses (13 mm–70 mm). A different set of specimens was utilized for each comparison. Results of this study indicate that, over a 17 year interval, the majority of test data from LNE and NIST agreed to within  ±1.0%, or less, for mineral fiber materials and to within  ±0.5%, or less, for expanded polystyrene. The long-term variability limit of 1% between the two laboratories is in good agreement with their current measurement uncertainties. Regression coefficients and their standard uncertainties for a straight-line model relating thermal conductivity to temperature from 280 K to 320 K were computed by material and laboratory. Graphical analysis of the data and corresponding fits exhibit consistent behavior by material type between the two laboratories. Sources of measurement variability are addressed.

  14. Demonstration of 12 nm resolution Fresnel zone plate lens based soft x-ray microscopy

    SciTech Connect

    Chao, W.; Kim, J.; Rekawa, S.; Fischer, P.; Anderson, E. H.

    2009-06-05

    To extend soft x-ray microscopy to a resolution of order 10 nm or better, we developed a new nanofabrication process for Fresnel zone plate lenses. The new process, based on the double patterning technique, has enabled us to fabricate high quality gold zone plates with 12 nm outer zones. Testing of the zone plate with the full-field transmission x-ray microscope, XM-1, in Berkeley, showed that the lens clearly resolved 12 nm lines and spaces. This result represents a significant step towards 10 nm resolution and beyond.

  15. Constitutive Description of 7075 Aluminum Alloy During Hot Deformation by Apparent and Physically-Based Approaches

    NASA Astrophysics Data System (ADS)

    Mirzadeh, Hamed

    2015-03-01

    Hot flow stress of 7075 aluminum alloy during compressive hot deformation was correlated to the Zener-Hollomon parameter through constitutive analyses based on the apparent approach and the proposed physically-based approach which accounts for the dependence of the Young's modulus and the self-diffusion coefficient of aluminum on temperature. It was shown that the latter approach not only results in a more reliable constitutive equation, but also significantly simplifies the constitutive analysis, which in turn makes it possible to conduct comparative hot working studies. It was also demonstrated that the theoretical exponent of 5 and the lattice self-diffusion activation energy of aluminum (142 kJ/mol) can be set in the hyperbolic sine law to describe the peak flow stresses and the resulting constitutive equation was found to be consistent with that resulted from the proposed physically-based approach.

  16. Distributed hot-wire anemometry based on Brillouin optical time-domain analysis.

    PubMed

    Wylie, Michael T V; Brown, Anthony W; Colpitts, Bruce G

    2012-07-02

    A distributed hot-wire anemometer based on Brillouin optical time-domain analysis is presented. The anemometer is created by passing a current through a stainless steel tube fibre bundle and monitoring Brillouin frequency changes in the presence of airflow. A wind tunnel is used to provide laminar airflow while the device response is calibrated against theoretical models. The sensitivity equation for this anemometer is derived and discussed. Airspeeds from 0 m/s to 10 m/s are examined, and the results show that a Brillouin scattering based distributed hot-wire anemometer is feasible.

  17. Tandem-structured, hot electron based photovoltaic cell with double Schottky barriers

    PubMed Central

    Lee, Young Keun; Lee, Hyosun; Park, Jeong Young

    2014-01-01

    We demonstrate a tandem-structured, hot electron based photovoltaic cell with double Schottky barriers. The tandem-structured, hot electron based photovoltaic cell is composed of two metal/semiconductor interfaces. Two types of tandem cells were fabricated using TiO2/Au/Si and TiO2/Au/TiO2, and photocurrent enhancement was detected. The double Schottky barriers lead to an additional pathway for harvesting hot electrons, which is enhanced through multiple reflections between the two barriers with different energy ranges. In addition, light absorption is improved by the band-to-band excitation of both semiconductors with different band gaps. Short-circuit current and energy conversion efficiency of the tandem-structured TiO2/Au/Si increased by 86% and 70%, respectively, compared with Au/Si metal/semiconductor nanodiodes, showing an overall solar energy conversion efficiency of 5.3%. PMID:24694838

  18. An infrared achromatic quarter-wave plate designed based on simulated annealing algorithm

    NASA Astrophysics Data System (ADS)

    Pang, Yajun; Zhang, Yinxin; Huang, Zhanhua; Yang, Huaidong

    2017-03-01

    Quarter-wave plates are primarily used to change the polarization state of light. Their retardation usually varies depending on the wavelength of the incident light. In this paper, the design and characteristics of an achromatic quarter-wave plate, which is formed by a cascaded system of birefringent plates, are studied. For the analysis of the combination, we use Jones matrix method to derivate the general expressions of the equivalent retardation and the equivalent azimuth. The infrared achromatic quarter-wave plate is designed based on the simulated annealing (SA) algorithm. The maximum retardation variation and the maximum azimuth variation of this achromatic waveplate are only about 1.8 ° and 0.5 ° , respectively, over the entire wavelength range of 1250-1650 nm. This waveplate can change the linear polarized light into circular polarized light with a less than 3.2% degree of linear polarization (DOLP) over that wide wavelength range.

  19. Plasma-based surface modification of polystyrene microtiter plates for covalent immobilization of biomolecules.

    PubMed

    North, Stella H; Lock, Evgeniya H; Cooper, Candace J; Franek, James B; Taitt, Chris R; Walton, Scott G

    2010-10-01

    In recent years, polymer surfaces have become increasingly popular for biomolecule attachment because of their relatively low cost and desirable bulk physicochemical characteristics. However, the chemical inertness of some polymer surfaces poses an obstacle to more expansive implementation of polymer materials in bioanalytical applications. We describe use of argon plasma to generate reactive hydroxyl moieties at the surface of polystyrene microtiter plates. The plates are then selectively functionalized with silanes and cross-linkers suitable for the covalent immobilization of biomolecules. This plasma-based method for microtiter plate functionalization was evaluated after each step by X-ray photoelectron spectroscopy, water contact angle analysis, atomic force microscopy, and bioimmobilization efficacy. We further demonstrate that the plasma treatment followed by silane derivatization supports direct, covalent immobilization of biomolecules on microtiter plates and thus overcomes challenging issues typically associated with simple physisorption. Importantly, biomolecules covalently immobilized onto microtiter plates using this plasma-based method retained functionality and demonstrated attachment efficiency comparable to commercial preactivated microtiter plates.

  20. Magnetic Fe-Co films electroplated in a deep-eutectic-solvent-based plating bath

    NASA Astrophysics Data System (ADS)

    Yanai, T.; Shiraishi, K.; Watanabe, Y.; Ohgai, T.; Nakano, M.; Suzuki, K.; Fukunaga, H.

    2015-05-01

    We fabricated Fe-Co films from a deep eutectic solvent (DES)-based plating bath and investigated magnetic properties of the plated films. The plating baths were obtained by stirring the mixture of choline chloride, ethylene glycol, FeCl2.4H2O, and CoCl2.6H2O. The composition of the plated films depended on the amount of FeCl2.4H2O in the plating bath, and Fe content of the films was varied from 0 to 100 at. %. Depending on the Fe content, the saturation magnetization and the coercivity of the films varied. The Fe76Co24 film shows high saturation magnetization and smooth surface, and the change in the saturation magnetization shows good agreement with the expected change by the Slater-Pauling curve. High current efficiency (>90%) could be obtained in the wide film composition. From these results, we concluded that the DES-based plating bath is one of effective baths for the Fe-Co films with high current efficiency.

  1. A feasibility study on laser rapid forming of a complete titanium denture base plate.

    PubMed

    Wu, Jiang; Gao, Bo; Tan, Hua; Chen, Jing; Tang, Chak-Yin; Tsui, Chi-Pong

    2010-05-01

    This work attempted to integrate the technologies of computer-aided design and computer-aided manufacture (CAD/CAM) and laser rapid forming (LRF) for the fabrication of the titanium plate of a complete denture. By the combination of laser scan and reverse engineering software, the standard triangulation language (STL)-formatted denture base plate was finally designed and sliced into a sequence of numerical controlled codes. The titanium (Ti) complete denture plate was finally built, layer-by-layer, on the LRF system. To evaluate the quality of fit, a virtual adaptation test that measured and compared the profiles of the laser free formed denture plate and those of the edentulous plaster cast had been conducted, and the mean deviation was found to be 0.34 mm. After traditional dental finishing techniques, a complete denture with a Ti base plate was then made and judged to be acceptable. The CAD/CAM/LRF system is a potential candidate and a new platform for the design and manufacture of custom-made Ti denture plates and restorations.

  2. Electroplated Fe-Co-Ni films prepared from deep-eutectic-solvent-based plating baths

    NASA Astrophysics Data System (ADS)

    Yanai, Takeshi; Shiraishi, Kotaro; Akiyoshi, Toshiki; Azuma, Keita; Watanabe, Yoshimasa; Ohgai, Takeshi; Morimura, Takao; Nakano, Masaki; Fukunaga, Hirotoshi

    2016-05-01

    We fabricated soft magnetic films from DES-based plating baths, and investigated magnetic properties of the plated films. The plating baths were obtained by stirring the mixture of choline chloride, ethylene glycol, FeCl2 ṡ 4H2O, NiCl2 ṡ 6H2O and CoCl2 ṡ 6H2O. The composition of the electroplated film depended on the amount of the reagent in the plating bath, and we consequently obtained the films with various composition. The current efficiency of the plating process shows high values (> 88 %) in the wide composition range. The soft magnetic films with low coercivity were obtained at the Fe compositions of ≈ 30 at.% and > 80 at.%, and we found that low coercivity could be realized by the control of the film composition. We also found that the Fe-rich films prepared from DES-based plating bath have some advantages as a soft magnetic phase for a nanocomposite magnet due to their high saturation magnetization and very fine crystal structure.

  3. Frequency domain active vibration control of a flexible plate based on neural networks

    NASA Astrophysics Data System (ADS)

    Liu, Jinxin; Chen, Xuefeng; He, Zhengjia

    2013-06-01

    A neural-network (NN)-based active control system was proposed to reduce the low frequency noise radiation of the simply supported flexible plate. Feedback control system was built, in which neural network controller (NNC) and neural network identifier (NNI) were applied. Multi-frequency control in frequency domain was achieved by simulation through the NN-based control systems. A pre-testing experiment of the control system on a real simply supported plate was conducted. The NN-based control algorithm was shown to perform effectively. These works lay a solid foundation for the active vibration control of mechanical structures.

  4. Hot-tearing of multicomponent Al-Cu alloys based on casting load measurements in a constrained permanent mold

    SciTech Connect

    Sabau, Adrian S; Mirmiran, Seyed; Glaspie, Christopher; Li, Shimin; Apelian, Diran; Shyam, Amit; Haynes, James A; Rodriguez, Andres

    2017-01-01

    Hot-tearing is a major casting defect that is often difficult to characterize, especially for multicomponent Al alloys used for cylinder head castings. The susceptibility of multicomponent Al-Cu alloys to hot-tearing during permanent mold casting was investigated using a constrained permanent mold in which the load and displacement was measured. The experimental results for hot tearing susceptibility are compared with those obtained from a hot-tearing criterion based temperature range evaluated at fraction solids of 0.87 and 0.94. The Cu composition was varied from approximately 5 to 8 pct. (weight). Casting experiments were conducted without grain refining. The measured load during casting can be used to indicate the severity of hot tearing. However, when small hot-tears are present, the load variation cannot be used to detect and assess hot-tearing susceptibility.

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

    ERIC Educational Resources Information Center

    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…

  6. Automated methodology for selecting hot and cold pixel for remote sensing based evapotranspiration mapping

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Surface energy fluxes, especially the latent heat flux from evapotranspiration (ET), determine exchanges of energy and mass between the hydrosphere, atmosphere, and biosphere. There are numerous remote sensing-based energy balance approaches such as METRIC and SEBAL that use hot and cold pixels from...

  7. An investigation of the initiation stage of hot corrosion in Ni-base alloys

    NASA Technical Reports Server (NTRS)

    Huang, T. T.; Meier, G. H.

    1979-01-01

    The commercial nickel base alloy, IN-738, and high purity laboratory alloys were prepared to simulate the effects of the major elements in IN-738. Results indicate that the initiation of hot corrosion attack of IN-738 and other similar alloys is the result of local penetration of molten salt through the protective oxide scale.

  8. Seismic and Geodynamic Constraints on Compositional Heterogeneity in the Lower Mantle: Implications for Deeply-Rooted Hot Upwellings Under the African and Pacific Plates

    NASA Astrophysics Data System (ADS)

    Forte, A. M.; Glisovic, P.; Rowley, D. B.; Simmons, N. A.; Grand, S. P.; Lu, C.

    2014-12-01

    We present the results of a series of tests that probe the possible existence of compositionally distinct material in the central core of the LLSVPs under the African and Pacific plates using tomography-based mantle flow models that employ several independently-derived viscosity profiles (Mitrovica & Forte 2004, Behn et al. 2004, Steinberger & Calderwood 2006, Forte et al. 2010). We also consider four global tomography models derived from seismic shear velocity data alone (Grand 2002, Panning & Romanowicz 2006, Kustowski et al. 2008, Ritsema et al. 2011). The possible combinations of viscosity and tomography models yield 16 different tests for compositional heterogeneity inside the LLSVPs. In all tests we begin with a mineral physical scaling between lower-mantle shear velocity and density anomalies that assumes thermal effects are dominant everywhere, including within the LLSVPs. We find it is not possible, in any of the tests, to obtain a satisfactory fit to surface geodynamic data, especially the global, long-wavelength gravity anomalies and space-geodetic inferences of excess CMB flattening with a purely thermal interpretation of lower-mantle heterogeneity. If we introduce compositionally-distinct material in the central portions of the LLSVPs, all tests show a notable improvement in the fit to the gravity anomaly and CMB ellipticity data. An optimal reconciliation of the gravity and CMB data is obtained by extending compositional heterogeneity upwards, with maximum-amplitude in the seismic D"-layer and tapering off to negligible values in the mid-mantle. A robust assessment of the dynamical impact of this deeply-rooted compositional heterogeneity is obtained with maps of "mean" convective flow, by averaging the results of all 16 test cases. We find (see map below) dominant lower-mantle upwellings below the axis of the East Pacific Rise (EPR), and under the Caroline Islands in the Western Pacific. Under the African plate we find large-scale upwellings under the

  9. Robust and fast license plate detection based on the fusion of color and edge feature

    NASA Astrophysics Data System (ADS)

    Cai, De; Shi, Zhonghan; Liu, Jin; Hu, Chuanping; Mei, Lin; Qi, Li

    2014-11-01

    Extracting a license plate is an important stage in automatic vehicle identification. The degradation of images and the computation intense make this task difficult. In this paper, a robust and fast license plate detection based on the fusion of color and edge feature is proposed. Based on the dichromatic reflection model, two new color ratios computed from the RGB color model are introduced and proved to be two color invariants. The global color feature extracted by the new color invariants improves the method's robustness. The local Sobel edge feature guarantees the method's accuracy. In the experiment, the detection performance is good. The detection results show that this paper's method is robust to the illumination, object geometry and the disturbance around the license plates. The method can also detect license plates when the color of the car body is the same as the color of the plates. The processing time for image size of 1000x1000 by pixels is nearly 0.2s. Based on the comparison, the performance of the new ratios is comparable to the common used HSI color model.

  10. Developing Model-Based Control Strategies for Hot Isostatic Pressing.

    DTIC Science & Technology

    1994-08-31

    feedback. It was found that density feedback based on PI control . (proportional plus integral) has better performance than proporational control alone. The...controller in linear system is the well- known proportional-integration ( PI ) controller . We will see that the unpredictable variations in HIP plant could be...effectively eliminated through PI feedback control. However, it should be noticed that, when introducing a PI control , the proportion gain and the

  11. Assessment of coal gasification/hot gas cleanup based advanced gas turbine systems

    SciTech Connect

    Not Available

    1990-12-01

    The major objectives of the joint SCS/DOE study of air-blown gasification power plants with hot gas cleanup are to: (1) Evaluate various power plant configurations to determine if an air-blown gasification-based power plant with hot gas cleanup can compete against pulverized coal with flue gas desulfurization for baseload expansion at Georgia Power Company's Plant Wansley; (2) determine if air-blown gasification with hot gas cleanup is more cost effective than oxygen-blown IGCC with cold gas cleanup; (3) perform Second-Law/Thermoeconomic Analysis of air-blown IGCC with hot gas cleanup and oxygen-blown IGCC with cold gas cleanup; (4) compare cost, performance, and reliability of IGCC based on industrial gas turbines and ISTIG power island configurations based on aeroderivative gas turbines; (5) compare cost, performance, and reliability of large (400 MW) and small (100 to 200 MW) gasification power plants; and (6) compare cost, performance, and reliability of air-blown gasification power plants using fluidized-bed gasifiers to air-blown IGCC using transport gasification and pressurized combustion.

  12. Processing Map and Mechanism of Hot Deformation of a Corrosion-Resistant Nickel-Based Alloy

    NASA Astrophysics Data System (ADS)

    Wang, L.; Liu, F.; Zuo, Q.; Cheng, J. J.; Chen, C. F.

    2017-01-01

    Hot deformation behavior of a corrosion-resistant nickel-based alloy was studied in temperature range of 1050-1200 °C and strain rate range of 0.001-10 s-1 by employing hot compression tests. An approach of processing map was used to reveal the hot workability and microstructural evolution during the hot deformation. The results show that different stable domains in the processing map associated with the microstructure evolution can be ascribed to different dynamic recrystallization (DRX) mechanisms. The discontinuous dynamic recrystallization (DDRX) grains evolved by the necklace mechanism are finer than those evolved by the ordinary mechanism, respectively, arising from the strong nucleation process and the growth process. If subjected to low temperature and high strain rate, the flow instability domain occurs, due to the continuous dynamic recrystallization (CDRX) based on the evolution of deformation micro-bands within the deformed grains. Based on the processing map, a DRX mechanism map is established, which can provide an idea for designing desired microstructure.

  13. High-Current Gain Two-Dimensional MoS₂-Base Hot-Electron Transistors.

    PubMed

    Torres, Carlos M; Lan, Yann-Wen; Zeng, Caifu; Chen, Jyun-Hong; Kou, Xufeng; Navabi, Aryan; Tang, Jianshi; Montazeri, Mohammad; Adleman, James R; Lerner, Mitchell B; Zhong, Yuan-Liang; Li, Lain-Jong; Chen, Chii-Dong; Wang, Kang L

    2015-12-09

    The vertical transport of nonequilibrium charge carriers through semiconductor heterostructures has led to milestones in electronics with the development of the hot-electron transistor. Recently, significant advances have been made with atomically sharp heterostructures implementing various two-dimensional materials. Although graphene-base hot-electron transistors show great promise for electronic switching at high frequencies, they are limited by their low current gain. Here we show that, by choosing MoS2 and HfO2 for the filter barrier interface and using a noncrystalline semiconductor such as ITO for the collector, we can achieve an unprecedentedly high-current gain (α ∼ 0.95) in our hot-electron transistors operating at room temperature. Furthermore, the current gain can be tuned over 2 orders of magnitude with the collector-base voltage albeit this feature currently presents a drawback in the transistor performance metrics such as poor output resistance and poor intrinsic voltage gain. We anticipate our transistors will pave the way toward the realization of novel flexible 2D material-based high-density, low-energy, and high-frequency hot-carrier electronic applications.

  14. Multi-scaled license plate detection based on the label-moveable maximal MSER clique

    NASA Astrophysics Data System (ADS)

    Gu, Qin; Yang, Jianyu; Kong, Lingjiang; Cui, Guolong

    2015-08-01

    In this paper, we consider a robust vehicle license plate detection problem for intelligent transportation systems in the presence of various illumination situations. We propose a robust and fast multi-scaled license plate detection and location algorithm, which exploits a Label-Moveable Maximal MSER clique. Specifically, first, we extract the candidate character regions using the Maximally Stable Extremal Region (MSER) features. Second, we divide each candidate character region into four types and extract the suspected initial node (the top-left character) based on its neighbor MSER distribution characteristic. Third, we label each candidate character region to accomplish license detection and location based on the detected suspected initial node and the corresponding label-moveable maximal MSER clique. The robust of license plate detection, the accuracy of character labeling for license location, and the improvement of calculation efficiency are evaluated via the real data.

  15. Preclinical Studies on Mesenchymal Stem Cell-Based Therapy for Growth Plate Cartilage Injury Repair

    PubMed Central

    Chung, Rosa; Foster, Bruce K.; Xian, Cory J.

    2011-01-01

    In the last two decades, there has been a strong interest in searching for biological treatments for regeneration of injured growth plate cartilage and prevention of its bony repair. Various means have been tried, including implantation of chondrocytes, mesenchymal stem cell (MSC), together with exogenous growth factor and scaffolds, and gene therapy. However, with the lack of success with chondrocytes, more research has focussed on MSC-based treatments. In addition to circumvent limitations with MSC-based treatments (including cell harvest-associated morbidity, difficulties/time/cost involved in MSC isolation and ex vivo expansion, and potential disease transmission), mobilising endogenous MSCs to the growth plate injury site and enhancing in situ regeneration mechanisms would represent an alternative attractive approach. Further studies are required to investigate the potential particularly in large animal models or clinical setting of the ex vivo MSC approach and the feasibility of the endogenous MSC in situ approach in growth plate regeneration. PMID:21808649

  16. Hydrocarbon Seepage during the Boreal Base Cretaceous Hot Shale Event

    NASA Astrophysics Data System (ADS)

    Hammer, Ø.; Hryniewicz, K.; Nakrem, H. A.; Little, C.

    2014-12-01

    We have identified a number of carbonate bodies interpreted as seep-related from near the Jurassic-Cretaceous boundary in Svalbard, arctic Norway. The paleoseeps discovered so far occur over 50 km along strike, representing a seepage field of considerable extent. Ammonites indicate a base Cretaceous (Late Volgian to Late Ryazanian) age. The carbonate bodies are highly fossiliferous, with a very diverse fauna consisting mainly of normal-marine species but also seep-restricted taxa. Carbonate d13C isotopes reach -46‰, which, considering mixture with seawater-derived carbon, is interpreted as indicating a biogenic methane source. It is of interest to note the correlation of this paleoseepage with an episode of extremely high burial of organic matter near the Jurassic-Cretaceous boundary, noted both in Svalbard (top Slottsmøya Member of the Agardhfjellet Formation), in the Barents Sea (Hekkingen Formation) and in the North Sea (Mandal Formation), possibly providing a shallow source for biogenic gas. Together with near contemporaneous events in the Boreal Realm such as ongoing rifting, the base Cretaceous unconformity, the Mjølnir meteorite impact and a possible minor extinction event, these finds contribute to the impression of the Jurassic-Cretaceous boundary as a highly dynamic and interesting time in the North Atlantic area.

  17. LQR-based optimization of multiple tuned resonators for plate sound radiation reduction

    NASA Astrophysics Data System (ADS)

    Michielsen, J.; Arteaga, I. Lopez; Nijmeijer, H.

    2016-02-01

    A linear quadratic regulator based optimization problem is formulated in order to minimize the broad-band low-frequency domain vibration and acoustic response of a baffled simply supported plate by means of multiple optimally tuned mass-spring-damper systems. To this end, we propose a robust method to obtain a (stable) state-space model describing the far-field radiated sound power, also known as the radiation filter. The Kirchhoff plate equation, which describes the plate vibrations, is discretized based on the Rayleigh-Ritz method. The resulting state-space models of the plate and the mass-springdamper systems are coupled to the radiation filter. Finally, the optimal spring stiffness and damping values of each mass-spring-damper system are successfully obtained by minimizing the kinetic energy or the far-field radiated sound power of the plate for low computational cost. In general, the results indicate that tuned mass-spring-damper systems have great potential to reduce the broadband low frequency vibration and acoustic response of vibro-acoustic systems. From the results, it can be concluded that there are fundamental differences between the optimal TMD systems if one minimizes the kinetic energy or the far-field radiated sound power.

  18. Hot news recommendation system from heterogeneous websites based on bayesian model.

    PubMed

    Xia, Zhengyou; Xu, Shengwu; Liu, Ningzhong; Zhao, Zhengkang

    2014-01-01

    The most current news recommendations are suitable for news which comes from a single news website, not for news from different heterogeneous news websites. Previous researches about news recommender systems based on different strategies have been proposed to provide news personalization services for online news readers. However, little research work has been reported on utilizing hundreds of heterogeneous news websites to provide top hot news services for group customers (e.g., government staffs). In this paper, we propose a hot news recommendation model based on Bayesian model, which is from hundreds of different news websites. In the model, we determine whether the news is hot news by calculating the joint probability of the news. We evaluate and compare our proposed recommendation model with the results of human experts on the real data sets. Experimental results demonstrate the reliability and effectiveness of our method. We also implement this model in hot news recommendation system of Hangzhou city government in year 2013, which achieves very good results.

  19. The Biological Sensor for Detection of Bacterial Cells in Liquid Phase Based on Plate Acoustic Wave

    NASA Astrophysics Data System (ADS)

    Borodina, Irina; Zaitsev, Boris; Shikhabudinov, Alexander; Guliy, Olga; Ignatov, Oleg; Teplykh, Andrey

    The interactions "bacterial cells - bacteriophages", "bacterial cells - antibodies" and "bacterial cells - mini- antibodies" directly in liquid phase were experimentally investigated with a help of acoustic sensor. The acoustic sensor under study represents two-channel delay line based on the plate of Y-X lithium niobate. One channel of delay line was electrically shorted, the second channel was electrically open. The liquid container was glued on plate surface between transducers of delay line. The dependencies of the change in phase and insertion loss on concentration of bacteriophages, antibodies, and mini- antibodies were obtained for both channels of delay line.

  20. Deformation behavior of SS400 Thick plate by high-frequency-induction-heating-based line heating

    NASA Astrophysics Data System (ADS)

    Lee, Kwang Seok; Eom, Deuk Ha; Lee, Jung-Hwan

    2013-03-01

    In this study, the line heating-induced permanent deformation behavior of an SS400 thick plate was investigated through both numerical analysis and experimental testing by applying high-frequency induction heating after generating dual-curvature by secondary line heating. First, an approach based on electromagnetic-thermal-structural coupling numerical analysis was adopted for predicting the temperature distribution and subsequent permanent deformation over the SS400 carbon steel plate. Experimental line heating was also carried out to validate the feasibility of the numerical analysis by applying newly designed laboratory-scale high-frequency (HF) induction-heating (IH) equipment. It was found that the shape of the heat-affected zone (HAZ) generated by HF IH and the subsequent microstructure of the SS400 carbon steel plate within the HAZ were strongly dependent on the input power. Permanent vertical deformation increased with an increase in the input power, regardless of the shape of the doubly curved plates (concave- or saddle-type plates). Transverse curvature determined in both the simulation and the experiment were investigated and compared.

  1. A millimeter-wave integrated-circuit antenna based on the Fresnel zone plate

    NASA Astrophysics Data System (ADS)

    Gouker, Mark A.; Smith, Glenn S.

    1992-05-01

    A moderate-gain, easily constructed, millimeter-wave IC antenna based on the Fresnel zone plate has been developed. The gain and beamwidth of the antenna can be varied by adjusting the diameter and focal length of the zone plate. A theory is developed which accurately predicts the on-axis gain, beamwidth, and sidelobe levels of antennas with zone-plate focal lengths greater than 8-9 lambda. Graphs are presented to aid in the design of other IC zone-plate antennas. The performance of the antenna without the reflector and lambda/4 spacer was investigated. The gain of the antenna with nothing behind the zone plate is found to approach that of the fully configured antenna with the lambda/4 spacer and reflector. The reflection from the open rings which is responsible for this phenomenon is enhanced as the dielectric constant of the substrate is increased. Thus, on substrates with high permittivity the reflector and lambda/4 spacer may not be necessary.

  2. Design of Stress-Strain Measuring System for Bulldozing Plate Based on Virtual Instrument Technology

    NASA Astrophysics Data System (ADS)

    Xu, S. C.; Li, J. Q.; Zhang, R.

    2006-10-01

    Soil is a kind of discrete, multiphase compound that is composed of soil particles, liquid and air. When soil is disturbed by bulldozing plate, the mechanical behavior of the soil will become very complex. Based on the law of action and reaction, the dynamic mechanical behavior of disturbed soil was indirectly analyzed by measuring and studying the forces on the bulldozing plate by soil currently, so a stress-strain virtual measuring system for bulldozing plate, which was designed by the graphical programming language DASYLab, was used to measure the horizontal force Fz acting on the bulldozing plate. In addition, during the course of design, the experimental complexities and the interferential factors influencing on signal logging were analyzed when bulldozing plate worked, so the anti-jamming methods of hardware and software technology were adopted correlatively. In the end, the horizontal force Fz was analyzed with Error Theory, the result shown that the quantificational analysis of Fz were identical to the qualitative results of soil well, and the error of the whole test system is under 5 percent, so the tress-strain virtual measuring system was stable and credible.

  3. A variable-order laminated plate theory based on the variational-asymptotical method

    NASA Technical Reports Server (NTRS)

    Lee, Bok W.; Sutyrin, Vladislav G.; Hodges, Dewey H.

    1993-01-01

    The variational-asymptotical method is a mathematical technique by which the three-dimensional analysis of laminated plate deformation can be split into a linear, one-dimensional, through-the-thickness analysis and a nonlinear, two-dimensional, plate analysis. The elastic constants used in the plate analysis are obtained from the through-the-thickness analysis, along with approximate, closed-form three-dimensional distributions of displacement, strain, and stress. In this paper, a theory based on this technique is developed which is capable of approximating three-dimensional elasticity to any accuracy desired. The asymptotical method allows for the approximation of the through-the-thickness behavior in terms of the eigenfunctions of a certain Sturm-Liouville problem associated with the thickness coordinate. These eigenfunctions contain all the necessary information about the nonhomogeneities along the thickness coordinate of the plate and thus possess the appropriate discontinuities in the derivatives of displacement. The theory is presented in this paper along with numerical results for the eigenfunctions of various laminated plates.

  4. Mechanism of beneficial effect of tantalum in hot corrosion of nickel-base superalloys

    NASA Technical Reports Server (NTRS)

    Fryburg, G. C.; Stearns, C. A.; Kohl, F. J.

    1977-01-01

    X-ray diffraction and electron microprobe analyses were used to examine a prominent NaTaO3 pattern formed in a number of nickel-base superalloys. It is found that a beneficial effect of tantalum with respect to hot corrosion attack arises from the ability of Ta2O5 to tie up Na2O and prevent the formation of a molten Na2MoO4 phase.

  5. Laser-printing of toner-based 96-microzone plates for immunoassays.

    PubMed

    Oliveira, Karoliny Almeida; Rodrigues de Oliveira, Cristina; Antonelli da Silveira, Lucimeire; Coltro, Wendell Karlos Tomazelli

    2013-02-21

    This work describes the quick and simple fabrication of toner-based 96-microzone plates by a direct-printing technology. The printer deposits a toner layer (ca. 5 μm thick) on the polyester surface which acts as a hydrophobic barrier to confine small volumes of sample on test zones (wells). A 96-microzone toner plate was explored to demonstrate its capability of performing enzyme-linked immunosorbent assay (ELISA). The detection of anti-immunoglobulin G (anti-IgG) and immunoglobulin M (IgM) antibodies has been successfully achieved in cell culture and serum samples, respectively. The use of a conventional microplate reader has allowed obtaining a limit of detection of 13 fmol of mouse IgG per zone on printed microplates. The IgM antibody has been detected in a serum sample collected from a patient infected with dengue virus. The detection of a primary infection has been provided by a microplate reader and also by a cell phone camera. Besides the bioanalytical feasibility, toner-based zones have shown good repeatability for inter-zone and intra-plate comparisons. The relative standard deviation (RSD) values for inter-zone (n = 12) and intra-plate (n = 3) comparisons were lower than 6% and 11%, respectively. Furthermore, it was found that the lifetime of each printed microplate depends on the storage temperature. The shelf life for devices stored at 10 °C has been estimated to be ca. four weeks.

  6. Extended Kalman Filter Based Neural Networks Controller For Hot Strip Rolling mill

    SciTech Connect

    Moussaoui, A. K.; Abbassi, H. A.; Bouazza, S.

    2008-06-12

    The present paper deals with the application of an Extended Kalman filter based adaptive Neural-Network control scheme to improve the performance of a hot strip rolling mill. The suggested Neural Network model was implemented using Bayesian Evidence based training algorithm. The control input was estimated iteratively by an on-line extended Kalman filter updating scheme basing on the inversion of the learned neural networks model. The performance of the controller is evaluated using an accurate model estimated from real rolling mill input/output data, and the usefulness of the suggested method is proved.

  7. A reconstructed edge-based smoothed DSG element based on global coordinates for analysis of Reissner-Mindlin plates

    NASA Astrophysics Data System (ADS)

    Yang, Gang; Hu, De'an; Long, Shuyao

    2017-02-01

    A reconstructed edge-based smoothed triangular element, which is incorporated with the discrete shear gap (DSG) method, is formulated based on the global coordinate for analysis of Reissner-Mindlin plates. A symbolic integration combined with the smoothing technique is implemented to calculate the smoothed finite element matrices, which is integrated along the boundaries of each smoothing cell. Numerical results show that the proposed element is free from shear locking, and its results are in good agreement with the exact solutions, even for very thin plates with extremely distorted elements. The proposed element gives more accurate results than the original DSG element without smoothing, and it can be taken as an alternative element for analysis of Reissner-Mindlin plates. The prominent feature of the present element is that the integration scheme is unified in the smoothed form for all of the finite element matrices.

  8. Component-Based Model for Single-Plate Shear Connections with Pretension and Pinched Hysteresis.

    PubMed

    Weigand, Jonathan M

    2017-02-01

    Component-based connection models provide a natural framework for modeling the complex behaviors of connections under extreme loads by capturing both the individual behaviors of the connection components, such as the bolt, shear plate, and beam web, and the complex interactions between those components. Component-based models also provide automatic coupling between the in-plane flexural and axial connection behaviors, a feature that is essential for modeling the behavior of connections under column removal. This paper presents a new component-based model for single-plate shear connections that includes the effects of pre-tension in the bolts and provides the capability to model standard and slotted holes. The component-based models are exercised under component-level deformations calculated from the connection demands via a practical rigid-body displacement model, so that the results of the presented modeling approach remains hand-calculable. Validation cases are presented for connections subjected to both seismic and column removal loading. These validation cases show that the component-based model is capable of predicting the response of single-plate shear connections for both seismic and column removal loads.

  9. Component-Based Model for Single-Plate Shear Connections with Pretension and Pinched Hysteresis

    PubMed Central

    Weigand, Jonathan M.

    2016-01-01

    Component-based connection models provide a natural framework for modeling the complex behaviors of connections under extreme loads by capturing both the individual behaviors of the connection components, such as the bolt, shear plate, and beam web, and the complex interactions between those components. Component-based models also provide automatic coupling between the in-plane flexural and axial connection behaviors, a feature that is essential for modeling the behavior of connections under column removal. This paper presents a new component-based model for single-plate shear connections that includes the effects of pre-tension in the bolts and provides the capability to model standard and slotted holes. The component-based models are exercised under component-level deformations calculated from the connection demands via a practical rigid-body displacement model, so that the results of the presented modeling approach remains hand-calculable. Validation cases are presented for connections subjected to both seismic and column removal loading. These validation cases show that the component-based model is capable of predicting the response of single-plate shear connections for both seismic and column removal loads. PMID:28133413

  10. Hot Workability of CuZr-Based Shape Memory Alloys for Potential High-Temperature Applications

    NASA Astrophysics Data System (ADS)

    Biffi, Carlo Alberto; Tuissi, Ausonio

    2014-07-01

    The research on high-temperature shape memory alloys has been growing because of the interest of several potential industrial fields, such as automotive, aerospace, mechanical, and control systems. One suitable candidate is given by the CuZr system, because of its relative low price in comparison with others, like the NiTi-based one. In this context, the goal of this work is the study of hot workability of some CuZr-based shape memory alloys. In particular, this study addresses on the effect of hot rolling process on the metallurgical and calorimetric properties of the CuZr system. The addition of some alloying elements (Cr, Co, Ni, and Ti) is taken into account and their effect is also put in comparison with each other. The alloys were produced by means of an arc melting furnace in inert atmosphere under the shape of cigars. Due to the high reactivity of these alloys at high temperature, the cigars were sealed in a stainless steel can before the processing and two different procedures of hot rolling were tested. The characterization of the rolled alloys is performed using discrete scanning calorimetry in terms of evolution of the martensitic transformation and scanning electron microscopy for the microstructural investigations. Additionally, preliminary tests of laser interaction has been also proposed on the alloy more interesting for potential applications, characterized by high transformation temperatures and its good thermal stability.

  11. Hot corrosion behavior of the spray-formed nickel-based superalloy

    NASA Astrophysics Data System (ADS)

    Xia, Min; Gu, Tian-Fu; Jia, Chong-Lin; Ge, Chang-Chun

    2016-12-01

    An investigation of low temperature hot corrosion is carried out on a spray-formed nickel-based superalloy FGH100 pre-coated with Na2SO4-NaCl at 700 °C for 100 h. Mass gain measurement, x-ray diffraction, scanning electron microscopy, and energy dispersive x-ray spectroscopy are used to study the corrosion behavior. Results reveal that corrosion behavior follows a sequence, that is, first rapidly proceeding, then gradually slowing down, and finally forming an outer layer composed of different types of oxides and an inner layer mainly comprised of sulfides. In-depth analysis reveals that the hot corrosion of FGH100 is a combined effect of oxidation-sulfidation and transfer of oxides.

  12. Are 'hot spots' hot spots?

    NASA Astrophysics Data System (ADS)

    Foulger, Gillian R.

    2012-07-01

    The term 'hot spot' emerged in the 1960s from speculations that Hawaii might have its origins in an unusually hot source region in the mantle. It subsequently became widely used to refer to volcanic regions considered to be anomalous in the then-new plate tectonic paradigm. It carried with it the implication that volcanism (a) is emplaced by a single, spatially restricted, mongenetic melt-delivery system, assumed to be a mantle plume, and (b) that the source is unusually hot. This model has tended to be assumed a priori to be correct. Nevertheless, there are many geological ways of testing it, and a great deal of work has recently been done to do so. Two fundamental problems challenge this work. First is the difficulty of deciding a 'normal' mantle temperature against which to compare estimates. This is usually taken to be the source temperature of mid-ocean ridge basalts (MORBs). However, Earth's surface conduction layer is ˜200 km thick, and such a norm is not appropriate if the lavas under investigation formed deeper than the 40-50 km source depth of MORB. Second, methods for estimating temperature suffer from ambiguity of interpretation with composition and partial melt, controversy regarding how they should be applied, lack of repeatability between studies using the same data, and insufficient precision to detect the 200-300 °C temperature variations postulated. Available methods include multiple seismological and petrological approaches, modelling bathymetry and topography, and measuring heat flow. Investigations have been carried out in many areas postulated to represent either (hot) plume heads or (hotter) tails. These include sections of the mid-ocean spreading ridge postulated to include ridge-centred plumes, the North Atlantic Igneous Province, Iceland, Hawaii, oceanic plateaus, and high-standing continental areas such as the Hoggar swell. Most volcanic regions that may reasonably be considered anomalous in the simple plate-tectonic paradigm have been

  13. Fabrication of a glucose biosensor based on inserted barrel plating gold electrodes.

    PubMed

    Hsu, Cheng-Teng; Chung, Hsieh-Hsun; Tsai, Dong-Mung; Fang, Mei-Yen; Hsiao, Hung-Chan; Zen, Jyh-Myng

    2009-01-01

    We demonstrate here the application of barrel plating gold electrodes for fabricating a new type of disposable amperometric glucose biosensor. It is prepared by inserting two barrel plating gold electrodes onto an injection molding plastic base followed by immobilizing with a bioreagent layer and membrane on the electrode surface. The primary function of barrel plating is to provide an economical way to electroplate manufactured parts. The manufacture procedure is simple and can increase the fabrication precision for automation in mass production. At the two-electrode system, the detection of glucose is linear up to 800 mg/dL (i.e., 44.5 mM, r(2) > 0.99) in pH 7.4 PBS with a sensitivity of 0.71 microA/mM. Excellent sensor-to-sensor reproducibility shows coefficients of variation of only 0.8-1.4% for the detection of 56.5-561.0 mg/dL glucose. In laboratory trials 176 capillary blood samples with a range of 30-572 mg/dL glucose are used to evaluate the clinical application of the biosensor. A good linear correlation is observed between the measured values of the proposed biosensor and laboratory reference. Error grid analysis verifies that the proposed technique is promising in fabricating biosensor strips on a mass scale. As successfully demonstrated by using whole blood glucose as a model analyte, the fabrication technique can extend into other barrel plating noble metal electrodes for various applications.

  14. Superior long-term stability of a glucose biosensor based on inserted barrel plating gold electrodes.

    PubMed

    Hsu, Cheng-Teng; Hsiao, Hung-Chan; Fang, Mei-Yen; Zen, Jyh-Myng

    2009-10-15

    Disposable one shot usage blood glucose strips are routinely used in the diagnosis and management of diabetes mellitus and their performance can vary greatly. In this paper we critically evaluated the long-term stability of glucose strips made of barrel plating gold electrodes. Compared to other glucose biosensing platforms of vapor deposited palladium and screen printed carbon electrodes, the proposed glucose biosensor was found to show the best stability among the three biosensing platforms in thermal acceleration experiments at 40 degrees C for 6 months with an average bias of 3.4% at glucose concentrations of 5-20 mM. The precision test of this barrel plating gold glucose biosensor also showed the best performance (coefficients of variation in the range of 1.4-2.4%) in thermal acceleration experiments at 40 degrees C, 50 degrees C and 70 degrees C for 27 days. Error grid analysis revealed that all measurements fell in zone A and zone B. Regression analysis showed no significant difference between the proposed biosensor and the reference method at 99% confidence level. The amperometric glucose biosensor fabricated by inserting two barrel plating gold electrodes onto an injection-molding plastic base followed by immobilizing with a bio-reagent layer and membrane was very impressive with a long-term stability up to 2.5 years at 25 degrees C. Overall, these results indicated that the glucose oxidase/barrel plating gold biosensing platform is ideal for long-term accurate glycemic control.

  15. Discovering Plate Boundaries Update: Builds Content Knowledge and Models Inquiry-based Learning

    NASA Astrophysics Data System (ADS)

    Sawyer, D. S.; Pringle, M. S.; Henning, A. T.

    2009-12-01

    Discovering Plate Boundaries (DPB) is a jigsaw-structured classroom exercise in which students explore the fundamental datasets from which plate boundary processes were discovered. The exercise has been widely used in the past ten years as a classroom activity for students in fifth grade through high school, and for Earth Science major and general education courses in college. Perhaps more importantly, the exercise has been used extensively for professional development of in-service and pre-service K-12 science teachers, where it simultaneously builds content knowledge in plate boundary processes (including natural hazards), models an effective data-rich, inquiry-based pedagogy, and provides a set of lesson plans and materials which teachers can port directly into their own classroom (see Pringle, et al, this session for a specific example). DPB is based on 4 “specialty” data maps, 1) earthquake locations, 2) modern volcanic activity, 3) seafloor age, and 4) topography and bathymetry, plus a fifth map of (undifferentiated) plate boundary locations. The jigsaw is structured so that students are first split into one of the four “specialties,” then re-arranged into groups with each of the four specialties to describe the boundaries of a particular plate. We have taken the original DPB materials, used the latest digital data sets to update all the basic maps, and expanded the opportunities for further student and teacher learning. The earthquake maps now cover the recent period including the deadly Banda Aceh event. The topography/bathymetry map now has global coverage and uses ice-free elevations, which can, for example, extend to further inquiry about mantle viscosity and loading processes (why are significant portions of the bedrock surface of Greenland and Antarctica below sea level?). The volcanic activity map now differentiates volcano type and primary volcanic lithology, allowing a more elaborate understanding of volcanism at different plate boundaries

  16. Hot coal gas desulfurization with manganese-based sorbents. Final report, September 1992--December 1994

    SciTech Connect

    Hepworth, M.T.; Slimane, R.B.

    1994-11-01

    The focus of much current work being performed by the Morgantown Energy Technology Center (METC) of the Department of Energy on hot coal-derived fuel gas desulfurization is in the use of zinc-based sorbents. METC has shown interest in formulating and testing manganese-based pellets as alternative effective sulfur sorbents in the 700 to 1200{degree}C temperature range. To substantiate the potential superiority of Mn-based pellets, a systematic approach toward the evaluation of the desulfurizing power of single-metal sorbents is developed based on thermodynamic considerations. This novel procedure considered several metal-based sorbents and singled out manganese oxide as a prime candidate sorbent capable of being utilized under a wide temperature range, irrespective of the reducing power (determined by CO{sub 2}/CO ratio) of the fuel gas. Then, the thermodynamic feasibility of using Mn-based pellets for the removal of H{sub 2}S from hot-coal derived fuel gases, and the subsequent oxidative regeneration of loaded (sulfided) pellets was established. It was concluded that MnO is the stable form of manganese for virtually all commercially available coal-derived fuel gases. In addition, the objective of reducing the H{sub 2}S concentration below 150 ppMv to satisfy the integrated gasification combined cycle system requirement was shown to be thermodynamically feasible. A novel process is developed for the manufacture of Mn-based spherical pellets which have the desired physical and chemical characteristics required.

  17. Imaging-based optical caliper for objects in hot manufacturing processes

    SciTech Connect

    Huang, Howard

    2013-04-03

    OG Technologies, Inc. (OGT), in conjunction with its industrial and academic partners, proposes to develop an Imaging-Based Optical Caliper (hereafter referred to as OC) for Objects in Hot Manufacturing Processes. The goal is to develop and demonstrate the OC with the synergy of OGT's current technological pool and other innovations to provide a light weight, robust, safe and accurate portable dimensional measurement device for hot objects with integrated wireless communication capacity to enable real time process control. The technical areas of interest in this project are the combination of advanced imaging, Sensor Fusion, and process control. OGT believes that the synergistic interactions between its current set of technologies and other innovations could deliver products that are viable and have high impact in the hot manufacture processes, such as steel making, steel rolling, open die forging, and glass industries, resulting in a new energy efficient control paradigm in the operations through improved yield, prolonged tool life and improved quality. In-line dimension measurement and control is of interest to the steel makers, yet current industry focus is on the final product dimension only instead of whole process due to the limit of man power, system cost and operator safety concerns. As sensor technologies advances, the industry started to see the need to enforce better dimensional control throughout the process, but lack the proper tools to do so. OGT along with its industrial partners represent the indigenous effort of technological development to serve the US steel industry. The immediate market that can use and get benefited from the proposed OC is the Steel Industry. The deployment of the OC has the potential to provide benefits in reduction of energy waste, CO2 emission, waste water amount, toxic waste, and so forth. The potential market after further expended function includes Hot Forging and Freight Industries. The OC prototypes were fabricated, and

  18. OUT Success Stories: Solar Hot Water Technology

    DOE R&D Accomplishments Database

    Clyne, R.

    2000-08-01

    Solar hot water technology was made great strides in the past two decades. Every home, commercial building, and industrial facility requires hot water. DOE has helped to develop reliable and durable solar hot water systems. For industrial applications, the growth potential lies in large-scale systems, using flat-plate and trough-type collectors. Flat-plate collectors are commonly used in residential hot water systems and can be integrated into the architectural design of the building.

  19. Combination of the Flow Disturbance Observer and Base Plate Jerk Feedback in a Pneumatic Positioning Stage

    NASA Astrophysics Data System (ADS)

    Wali, Mohebullah; Wakui, Shinji

    Pneumatic actuation systems are commonly used to drive the positioning stage due to several merits. However, one of the critical demerits of the pneumatic systems is the problem of the compressibility, which results in the flow disturbance. Another problem of the positioning stage can be addressed to the vibration which occurs due to the active condition of the base plate. This paper concerns the mentioned two issues in a pneumatic positioning stage. In order to suppress the flow disturbance and to reduce the horizontal vibration of the stage due to the reaction force, a combined control scheme is proposed. This scheme is composed of the fusion of flow disturbance observer (FDOB) and base plate jerk feedback (BPJFB) scheme. An enhanced experimental methodology is provided to successfully implement the fusion of the mentioned feedback controllers. The results show the effectiveness of the proposed method.

  20. Measurements of strain at plate boundaries using space based geodetic techniques

    NASA Technical Reports Server (NTRS)

    Robaudo, Stefano; Harrison, Christopher G. A.

    1993-01-01

    We have used the space based geodetic techniques of Satellite Laser Ranging (SLR) and VLBI to study strain along subduction and transform plate boundaries and have interpreted the results using a simple elastic dislocation model. Six stations located behind island arcs were analyzed as representative of subduction zones while 13 sites located on either side of the San Andreas fault were used for the transcurrent zones. The length deformation scale was then calculated for both tectonic margins by fitting the relative strain to an exponentially decreasing function of distance from the plate boundary. Results show that space-based data for the transcurrent boundary along the San Andreas fault help to define better the deformation length scale in the area while fitting nicely the elastic half-space earth model. For subduction type bonndaries the analysis indicates that there is no single scale length which uniquely describes the deformation. This is mainly due to the difference in subduction characteristics for the different areas.

  1. Effects of cobalt on the hot workability of nickel-base superalloys

    NASA Technical Reports Server (NTRS)

    Jarrett, R. N.; Collier, J. P.; Tien, J. K.

    1984-01-01

    The effect of cobalt on the workability of nickel-base superalloys is examined with reference to experimental results for four heats of alloys based on the Nimonic 115 composition with varying amounts of nickel substituted for the nominal 14 percent cobalt. It is shown that Co lowers the gamma-prime solvus, which in turn lowers the Cr23C6 carbide solvus. It is further shown that these solvus temperatures bracket the hot working range for the alloys. However, thermomechanical processing modifications reflecting the effect of Co on the gamma-prime and carbide solvi are shown to restore the workability and the properties of alloys with little or no cobalt.

  2. Validation of the Hot Strip Mill Model

    SciTech Connect

    Richard Shulkosky; David Rosberg; Jerrud Chapman

    2005-03-30

    The Hot Strip Mill Model (HSMM) is an off-line, PC based software originally developed by the University of British Columbia (UBC) and the National Institute of Standards and Technology (NIST) under the AISI/DOE Advanced Process Control Program. The HSMM was developed to predict the temperatures, deformations, microstructure evolution and mechanical properties of steel strip or plate rolled in a hot mill. INTEG process group inc. undertook the current task of enhancing and validating the technology. With the support of 5 North American steel producers, INTEG process group tested and validated the model using actual operating data from the steel plants and enhanced the model to improve prediction results.

  3. Investigation on the effect of MR elastomer based adaptive vibration absorbers on the radiated sound from circular elastic plates

    NASA Astrophysics Data System (ADS)

    Hemmatian, M.; Sedaghati, R.

    2016-04-01

    This study aims to investigate the effect of using magnetorheological elastomer (MRE)-based adaptive tuned vibration absorbers (ATVA) on the sound transmission in an elastic plate. Sound transmission loss (STL) of an elastic circular thin plate is analytically studied. The plate is excited by a plane acoustic wave as an incident sound and the displacement of the plate is calculated using corresponding mode shapes of the system for clamped boundary condition. Rayleigh integral approach is used to express the transmitted sound pressure in terms of the plate's displacement modal amplitude. In order to increase sound transmission loss of the plate, the MRE-based ATVA is considered. The basic idea is to be able to change the stiffness of the ATVA by varying magnetic field in order to reduce the transmitted acoustic energy of the host structure in a wide frequency range. Here, a MRE-based ATVA under the shear mode consisting of an oscillator mass, magnetic conductor, coils and MRE is investigated. In order to predict the viscoelastic characteristics of the field-dependent MRE based on the applied magnetic field, the double pole model is used. Finally, MRE-based ATVAs are integrated with the plate to absorb the plate energy with the aim of decreasing the transmitted sound power. Results show that plate with integrated MRE-based ATVAs suppresses the axisymmetric vibration of the plate and thus considerably improves the STL. Parametric studies on the influence of the position of MRE-based ATVAs and the effects of applied current on their performance are also presented.

  4. Analytical model development of an eddy-current-based non-contacting steel plate conveyance system

    NASA Astrophysics Data System (ADS)

    Liu, Cheng-Tsung; Lin, Sheng-Yang; Yang, Yung-Yi; Hwang, Chang-Chou

    A concise model for analyzing and predicting the quasi-static electromagnetic characteristics of an eddy-current-based non-contacting steel plate conveyance system has been developed. Confirmed by three-dimensional (3-D) finite element analysis (FEA), adequacy of the analytical model can be demonstrated. Such an effective approach, which can be conveniently used by the potential industries for preliminary system operational performance evaluations, will be essential for designers and on-site engineers.

  5. Burner Rig Hot Corrosion of Five Ni-Base Alloys Including Mar-M247

    NASA Technical Reports Server (NTRS)

    Nesbitt, James A.; Helmink, R.; Harris, K.; Erickson, G.

    2000-01-01

    The hot corrosion resistance of four new Ni-base superalloys was compared to that of Mar-M247 by testing in a Mach 0.3 burner rig at 900 C for 300 1-hr cycles. While the Al content was held the same as in the Mar-M247, the Cr and Co levels in the four new alloys were decreased while other strengthening elements (Re, Ta) were increased. Surprisingly, despite their lower Cr and Co contents, the hot corrosion behavior of all four new alloys was superior to that of the Mar-M247 alloy. The Mar-M247 alloy began to lose weight almost immediately whereas the other four alloys appeared to undergo an incubation period of 50-150 1-hr cycles. Examination of the cross-sectional microstructures showed regions of rampant corrosion attack (propagation stage) in all five alloys after 300 1-hr cycles . This rampant corrosion morphology was similar for each of the alloys with Ni and Cr sulfides located in an inner subscale region. The morphology of the attack suggests a classic "Type I", or high temperature, hot corrosion attack.

  6. DEVELOPMENT OF A CALCIUM-BASED SORBENT FOR HOT GAS CLEANUP

    SciTech Connect

    T.D. Wheelock; L.K. Doraiswamy; K. Constant

    1999-10-01

    The development and testing of potential calcium-based sorbents for hot gas cleanup continued. One of the most promising materials combines powdered limestone and a calcium aluminate cement by two step pelletization followed by steam curing. Reasonably strong pellets are produced with good adsorption characteristics by incorporating 20 wt.% cement in the core and 40 wt.% cement in the shell. The resulting 4.76 mm diameter pellets are capable of withstanding a crushing force approaching 11.5 N/mm before breaking and are also capable of removing H{sub 2}S from dilute, hot gas streams. The pellets are also regenerable and reusable. Another promising material combines calcium carbonate powder and finely ground calcined alumina in tablet form. The small tablets are prepared by mixing the materials with water to form a thick paste which is then molded and dried. The tablets are hardened by calcining at either 1000 to 1100 C. The resulting tablets are strong and capable of removing H{sub 2}S from a dilute, hot gas stream.

  7. Reevaluation of plate motion models based on hotspot tracks in the Atlantic and Indian Oceans

    SciTech Connect

    Baksi, A.K.

    1999-01-01

    Plate motion models based on hotspot tracks in the Atlantic and Indian Oceans predict minimal movement (less than a few millimeters per year) between these hotspots and their counterparts in the Pacific Ocean for the past {approximately}100 m.yr., whereas plate circuit exercises indicate relative motions of {approximately}20 mm/yr. Hotspot-based models also suggest that the Rajmahal Traps, India, were located {approximately}1,000 km away from the Kerguelen hotspot at {approximately}115 Ma, and the Deccan Traps, India, were located a similar distance from the Reunion hotspot at {approximately}65 Ma; this is at odds with conclusions derived from paleomagnetism, plate circuits, and geochemical parameters that suggest a genetic link between flood basalt provinces in India and hotspots in the Indian Ocean. These divergent views may be explained by plume action {approximately}1,000 km from its center or errors in the hotspot motion models. The latter hypothesis is scrutinized in this article by examination of the radiometric ages for hotspot tracks in the Atlantic and Indian Oceans. The {sup 40}/{sup 39}Ar step-heating data for rocks defining the tracks of the Reunion and Kerguelen hotspots in the Indian Ocean and the Great Metero and Tristan da Cunha hotspots in the Atlantic Ocean are critically reexamined. Of {approximately}35 such ages utilized for deriving plate motion models for the past 130 m.yr., at best, only three ({approximately}32, {approximately}50, and {approximately}52 Ma) in the Indian Ocean and one ({approximately}65 Ma) for the Atlantic Ocean may be treated as crystallization ages. Conclusions based on hotspot track modeling for Late Cretaceous to Eocene time are suspect, and those for the Early to Late Cretaceous period are untenable. In the absence of precise age data for the tracks of hotspots in the Atlantic and Indian Oceans, and inconsistent age progressions noted within a single volcanic chain, plate circuit models serve as the superior technique

  8. Fabrication and characterization of monolithically integrated microchannel plates based on amorphous silicon.

    PubMed

    Franco, Andrea; Geissbühler, Jonas; Wyrsch, Nicolas; Ballif, Christophe

    2014-04-04

    Microchannel plates are vacuum-based electron multipliers for particle--in particular, photon--detection, with applications ranging from image intensifiers to single-photon detectors. Their key strengths are large signal amplification, large active area, micrometric spatial resolution and picosecond temporal resolution. Here, we present the first microchannel plate made of hydrogenated amorphous silicon (a-Si:H) instead of lead glass. The breakthrough lies in the possibility of realizing amorphous silicon-based microchannel plates (AMCPs) on any kind of substrate. This achievement is based on mastering the deposition of an ultra-thick (80-120 μm) stress-controlled a-Si:H layer from the gas phase at temperatures of about 200 °C and micromachining the channels by dry etching. We fabricated AMCPs that are vertically integrated on metallic anodes of test structures, proving the feasibility of monolithic integration of, for instance, AMCPs on application-specific integrated circuits for signal processing. We show an electron multiplication factor exceeding 30 for an aspect ratio, namely channel length over aperture, of 12.5:1. This result was achieved for input photoelectron currents up to 100 pA, in the continuous illumination regime, which provides a first evidence of the a-Si:H effectiveness in replenishing the electrons dispensed in the multiplication process.

  9. Fabrication and characterization of monolithically integrated microchannel plates based on amorphous silicon

    PubMed Central

    Franco, Andrea; Geissbühler, Jonas; Wyrsch, Nicolas; Ballif, Christophe

    2014-01-01

    Microchannel plates are vacuum-based electron multipliers for particle—in particular, photon— detection, with applications ranging from image intensifiers to single-photon detectors. Their key strengths are large signal amplification, large active area, micrometric spatial resolution and picosecond temporal resolution. Here, we present the first microchannel plate made of hydrogenated amorphous silicon (a-Si:H) instead of lead glass. The breakthrough lies in the possibility of realizing amorphous silicon-based microchannel plates (AMCPs) on any kind of substrate. This achievement is based on mastering the deposition of an ultra-thick (80–120 μm) stress-controlled a-Si:H layer from the gas phase at temperatures of about 200°C and micromachining the channels by dry etching. We fabricated AMCPs that are vertically integrated on metallic anodes of test structures, proving the feasibility of monolithic integration of, for instance, AMCPs on application-specific integrated circuits for signal processing. We show an electron multiplication factor exceeding 30 for an aspect ratio, namely channel length over aperture, of 12.5:1. This result was achieved for input photoelectron currents up to 100 pA, in the continuous illumination regime, which provides a first evidence of the a-Si:H effectiveness in replenishing the electrons dispensed in the multiplication process. PMID:24698955

  10. Vibration-based damage detection in plates by using time series analysis

    NASA Astrophysics Data System (ADS)

    Trendafilova, Irina; Manoach, Emil

    2008-07-01

    This paper deals with the problem of vibration health monitoring (VHM) in structures with nonlinear dynamic behaviour. It aims to introduce two viable VHM methods that use large amplitude vibrations and are based on nonlinear time series analysis. The methods suggested explore some changes in the state space geometry/distribution of the structural dynamic response with damage and their use for damage detection purposes. One of the methods uses the statistical distribution of state space points on the attractor of a vibrating structure, while the other one is based on the Poincaré map of the state space projected dynamic response. In this paper both methods are developed and demonstrated for a thin vibrating plate. The investigation is based on finite element modelling of the plate vibration response. The results obtained demonstrate the influence of damage on the local dynamic attractor of the plate state space and the applicability of the proposed strategies for damage assessment. The approach taken in this study and the suggested VHM methods are rather generic and permit development and applications for other more complex nonlinear structures.

  11. Antinociception versus serum concentration relationships following acute administration of intravenous morphine in male and female Sprague-Dawley rats: differences between the tail flick and hot plate nociceptive tests.

    PubMed

    South, Samantha M; Edwards, Stephen R; Smith, Maree T

    2009-01-01

    1. Antinociception versus serum morphine concentration relationships were defined in male and female Sprague-Dawley rats administered single intravenous (i.v.) bolus doses of morphine, using the hot plate (2.1-14 mg/kg) and tail flick tests (1-8 mg/kg). 2. Serum concentrations of morphine and morphine-3-glucuronide (M3G), its major metabolite in the rat, were assayed using high-performance liquid chromatography (HPLC) with electrochemical detection. 3. Significantly higher (P < 0.05) values of peak antinociception (approximately 1.7-fold), as well as the extent and duration of antinociception (approximately fourfold), were observed in male compared with female rats administered 10 mg/kg morphine in the hot plate test. Although there were no significant sex-related differences in the area under the serum morphine concentration versus time curve (AUC) at this dose, systemic exposure to M3G (M3G AUC) was significantly higher (approximately twofold; P < 0.05) in female than male rats. 4. In contrast with most previous studies investigating sex differences in morphine antinociception in rats, the antinociceptive effects of single i.v. doses of morphine (1-8 mg/kg) in the tail flick test did not differ significantly between male and female rats. 5. Morphine ED(50) and EC(50) values (95% confidence intervals) for antinociception in the hot plate test were significantly lower (P < 0.05) in male rats (ED(50) 8.4 mg/kg (7.6-9.2); EC(50) 1.8 nmol/L (1.5-2.1)) compared with female rats (ED(50) 10.6 mg/kg (9.1-12.0); EC(50) 3.7 nmol/L (3.4-4.1)). However, in the tail flick test, there was no significant difference between male and female rats in ED(50) (1.8 (0.4-3.3) and 1.4 mg/kg (0.4-2.5), respectively) or EC(50) (0.5 (0.3-0.6) and 0.4 nmol/L (0.2-0.5), respectively) values. 6. Supraspinal attenuation of morphine antinociception by M3G may account for these differences.

  12. A Prerecognition Model for Hot Topic Discovery Based on Microblogging Data

    PubMed Central

    Zhu, Tongyu

    2014-01-01

    The microblogging is prevailing since its easy and anonymous information sharing at Internet, which also brings the issue of dispersing negative topics, or even rumors. Many researchers have focused on how to find and trace emerging topics for analysis. When adopting topic detection and tracking techniques to find hot topics with streamed microblogging data, it will meet obstacles like streamed microblogging data clustering, topic hotness definition, and emerging hot topic discovery. This paper schemes a novel prerecognition model for hot topic discovery. In this model, the concepts of the topic life cycle, the hot velocity, and the hot acceleration are promoted to calculate the change of topic hotness, which aims to discover those emerging hot topics before they boost and break out. Our experiments show that this new model would help to discover potential hot topics efficiently and achieve considerable performance. PMID:25254235

  13. McClellan Air Force Base plating shop rinse water recycle system

    SciTech Connect

    Miyasaki, D.H.; LaRue, D.M.

    1988-01-01

    The Idaho National Engineering Laboratory performed an assessment on the technical and economic viability of a total recycle of the rinse water generated by the Sacramento Air Logistics Center Plating Shop, located in Building 243-G of McClellan Air Force Base. A proposed conceptual design using ion exchange beds for the recycle of plating shop rinse water is presented and evaluated. Laboratory studies indicated that the proposed recycle system meets all functional and operational requirements that were identified. But concern over the amount of waste generated during the process of regenerating the ion exchange columns prompted an evaluation of a reverse osmosis unit, which would function as pretreatment before the ion exchange process. Further studies indicated that the addition of this pretreatment process would improve the performance of the recycle system, but that the cost of construction and operation would be significantly higher. Based on technical and economic evaluations, the ion exchange system is the recommended recycle system for the plating shop. 9 figs.

  14. Miniaturization of mitotic index cell-based assay using "wall-less" plate technology.

    PubMed

    Le Guezennec, Xavier; Phong, Mark; Nor, Liyana; Kim, Namyong

    2014-03-01

    The use of microscopic imaging for the accurate assessment of cells in mitosis is hampered by the round morphology of mitotic cells, which renders them poorly adherent and highly susceptible to loss during the washing stage of cell-based assays. Here, to circumvent these limitations, we make use of DropArray, a recent technology that allows high retention of weakly adherent cells and suspension cells. DropArray offers the competitive advantage of maintaining the classic high throughput format of microtiter plates while reducing classic microwell volume by up to 90% by using a drop format. Here, we present a mitotic index cell-based assay using the mitosis marker phospho histone H3 at serine 10 on a DropArray 384-well plate format. Dose-response curve analysis of the mitotic index assay with an antimitotic drug (docetaxel) on DropArray is presented that shows an effective dosage compared to previous established results similar to those obtained with conventional microtiter plates. The mitotic index assay with DropArray showed a Z-factor >0.6. Our results validate DropArray as a suitable platform for high throughput screening for compounds affecting mitosis or the cell cycle.

  15. Calibration of a microchannel plate based extreme ultraviolet grazing incident spectrometer at the Advanced Light Source.

    PubMed

    Bakeman, M S; van Tilborg, J; Sokollik, T; Baum, D; Ybarrolaza, N; Duarte, R; Toth, C; Leemans, W P

    2010-10-01

    We present the design and calibration of a microchannel plate based extreme ultraviolet spectrometer. Calibration was performed at the Advance Light Source (ALS) at the Lawrence Berkeley National Laboratory (LBNL). This spectrometer will be used to record the single shot spectrum of radiation emitted by the tapered hybrid undulator (THUNDER) undulator installed at the LOASIS GeV-class laser-plasma-accelerator. The spectrometer uses an aberration-corrected concave grating with 1200 lines/mm covering 11-62 nm and a microchannel plate detector with a CsI coated photocathode for increased quantum efficiency in the extreme ultraviolet. A touch screen interface controls the grating angle, aperture size, and placement of the detector in vacuum, allowing for high-resolution measurements over the entire spectral range.

  16. Calibration of a microchannel plate based extreme ultraviolet grazing incident spectrometer at the Advanced Light Source

    SciTech Connect

    Bakeman, M. S.; Tilborg, J. van; Sokollik, T.; Baum, D.; Ybarrolaza, N.; Duarte, R.; Toth, C.; Leemans, W. P.

    2010-10-15

    We present the design and calibration of a microchannel plate based extreme ultraviolet spectrometer. Calibration was performed at the Advance Light Source (ALS) at the Lawrence Berkeley National Laboratory (LBNL). This spectrometer will be used to record the single shot spectrum of radiation emitted by the tapered hybrid undulator (THUNDER) undulator installed at the LOASIS GeV-class laser-plasma-accelerator. The spectrometer uses an aberration-corrected concave grating with 1200 lines/mm covering 11-62 nm and a microchannel plate detector with a CsI coated photocathode for increased quantum efficiency in the extreme ultraviolet. A touch screen interface controls the grating angle, aperture size, and placement of the detector in vacuum, allowing for high-resolution measurements over the entire spectral range.

  17. Chip-based optical microscopy for imaging membrane sieve plates of liver scavenger cells

    NASA Astrophysics Data System (ADS)

    Helle, Øystein I.; Øie, Cristina I.; McCourt, Peter; Ahluwalia, Balpreet S.

    2015-08-01

    The evanescent field on top of optical waveguides is used to image membrane network and sieve-plates of liver endothelial cells. In waveguide excitation, the evanescent field is dominant only near the surface (~100-150 nm) providing a default optical sectioning by illuminating fluorophores in close proximity to the surface and thus benefiting higher signal-to-noise ratio. The sieve plates of liver sinusoidal endothelial cells are present on the cell membrane, thus near-field waveguide chip-based microscopy configuration is preferred over epi-fluorescence. The waveguide chip is compatible with optical fiber components allowing easy multiplexing to different wavelengths. In this paper, we will discuss the challenges and opportunities provided by integrated optical microscopy for imaging cell membranes.

  18. A novel disturbance-observer based friction compensation scheme for ball and plate system.

    PubMed

    Wang, Yongkun; Sun, Mingwei; Wang, Zenghui; Liu, Zhongxin; Chen, Zengqiang

    2014-03-01

    Friction is often ignored when designing a controller for the ball and plate system, which can lead to steady-error and stick-slip phenomena, especially for the small amplitude command. It is difficult to achieve high-precision control performance for the ball and plate system because of its friction. A novel reference compensation strategy is presented to attenuate the aftereffects caused by the friction. To realize this strategy, a linear control law is proposed based on a reduced-order observer. Neither the accurate friction model nor the estimation of specific characteristic parameters is needed in this design. Moreover, the describing function method illustrates that the limit cycle can be avoided. Finally, the comparative mathematical simulations and the practical experiments are used to validate the effectiveness of the proposed method.

  19. Recent progress in LWIR HOT photoconductors based on MOCVD grown (100) HgCdTe

    NASA Astrophysics Data System (ADS)

    Gawron, W.; Kębłowski, A.; Kopytko, M.; Madejczyk, P.; Martyniuk, P.; Pędzińska, M.; Piotrowski, A.; Piotrowski, J.; Rogalski, A.; Romanis, M.; Sosna, A.

    2016-10-01

    Hg1-x Cd x Te photoconductors grown in (100) crystallographic orientation are prone to demonstrating high crystalline quality, which results in a lower number of generation-recombination centers, lower noise and high responsivity. This work presents the optimum growth conditions and results of the characterization both of layers and high operating temperature (HOT) long wavelength infrared (LWIR) photoconductive devices based on them. The (100) HgCdTe photoconductor attains D*(13 μm) equal to 6.5 × 109 cmHz1/2W-1 at 200 K and therefore outperforms its (111)B counterpart.

  20. High Q-factor colloidal nanocrystal-based vertical microcavity by hot embossing technology

    NASA Astrophysics Data System (ADS)

    Martiradonna, Luigi; Carbone, Luigi; De Giorgi, Milena; Manna, Liberato; Gigli, Giuseppe; Cingolani, Roberto; De Vittorio, Massimo

    2006-05-01

    We report on the fabrication and optical characterization of vertical hybrid microcavities in which a layer of colloidal nanocrystals dispersed in an organic matrix is embedded between two inorganic mirrors. The devices are fabricated by a technique based on the unconventional use of the hot embossing technology, which allows a very fine control of the cavity length. The technique exploits a λ-thick microstructured dielectric top mirror pressed onto the bottom one, previously coated with the active layer, to sandwich the cavity and precisely control its thickness. Room-temperature photoluminescence measurements show a Q factor as high as 146 for our devices.

  1. Boattail Plates With Non-Rectangular Geometries For Reducing Aerodynamic Base Drag Of A Bluff Body In Ground Effect

    DOEpatents

    Ortega, Jason M.; Sabari, Kambiz

    2006-03-07

    An apparatus for reducing the aerodynamic base drag of a bluff body having a leading end, a trailing end, a top surface, opposing left and right side surfaces, and a base surface at the trailing end substantially normal to a longitudinal centerline of the bluff body, with the base surface joined (1) to the left side surface at a left trailing edge, (2) to the right side surface at a right trailing edge, and (3) to the top surface at a top trailing edge. The apparatus includes left and right vertical boattail plates which are orthogonally attached to the base surface of the bluff body and inwardly offset from the left and right trailing edges, respectively. This produces left and right vertical channels which generate, in a flowstream substantially parallel to the longitudinal centerline, respective left and right vertically-aligned vortical structures, with the left and right vertical boattail plates each having a plate width defined by a rear edge of the plate spaced from the base surface. Each plate also has a peak plate width at a location between top and bottom ends of the plate corresponding to a peak vortex of the respective vertically-aligned vortical structures.

  2. Hybrid Semiloof elements for plates and shells based upon a modified Hu-Washizu principle

    NASA Technical Reports Server (NTRS)

    Pian, T. H. H.; Sumihara, K.

    1984-01-01

    Hybrid SemiLoof elements for plates and shells are developed based upon modified Hu-Washizu principle. In the new version of the assumed stress hybrid formulation the equilibrium equations are satisfied through the introduction of internal displacement parameters as Lagrange multipliers. The inversion of the resulting H-matrices is simplified particularly when the stresses are expressed in terms of natural coordinates. A 24-DOF triangular element and a 32-DOF quadrilateral element based on shallow shell theory are derived and evaluated.

  3. MICROSCOPY CHARACTERIZATION OF U-MO BEARING MINI-PLATES FABRICATED BY HOT ISOSTATIC PRESSING (HIPPING) WITH A LONG THERMAL CYCLE

    SciTech Connect

    Jan-Fong Jue

    2007-07-01

    The RERTR Program has formed the Production Development Team to coordinate fabrication efforts to produce the fuel elements for the qualifying irradiation tests. These fuel elements will be fabricated in production facilities. Fabrication development data will be shared with all participants on the development team. The INL has been developing a method of cladding using a Hot Isostatic Press (HIP). The operating parameters were varied to understand the impact of time, pressure and temperature on the reaction between the fuel and the cladding. This report details some of the data produced to date.

  4. Extrapolation of Calibration Curve of Hot-wire Spirometer Using a Novel Neural Network Based Approach.

    PubMed

    Ardekani, Mohammad Ali; Nafisi, Vahid Reza; Farhani, Foad

    2012-10-01

    Hot-wire spirometer is a kind of constant temperature anemometer (CTA). The working principle of CTA, used for the measurement of fluid velocity and flow turbulence, is based on convective heat transfer from a hot-wire sensor to a fluid being measured. The calibration curve of a CTA is nonlinear and cannot be easily extrapolated beyond its calibration range. Therefore, a method for extrapolation of CTA calibration curve will be of great practical application. In this paper, a novel approach based on the conventional neural network and self-organizing map (SOM) method has been proposed to extrapolate CTA calibration curve for measurement of velocity in the range 0.7-30 m/seconds. Results show that, using this approach for the extrapolation of the CTA calibration curve beyond its upper limit, the standard deviation is about -0.5%, which is acceptable in most cases. Moreover, this approach for the extrapolation of the CTA calibration curve below its lower limit produces standard deviation of about 4.5%, which is acceptable in spirometry applications. Finally, the standard deviation on the whole measurement range (0.7-30 m/s) is about 1.5%.

  5. Extrapolation of Calibration Curve of Hot-wire Spirometer Using a Novel Neural Network Based Approach

    PubMed Central

    Ardekani, Mohammad Ali; Nafisi, Vahid Reza; Farhani, Foad

    2012-01-01

    Hot-wire spirometer is a kind of constant temperature anemometer (CTA). The working principle of CTA, used for the measurement of fluid velocity and flow turbulence, is based on convective heat transfer from a hot-wire sensor to a fluid being measured. The calibration curve of a CTA is nonlinear and cannot be easily extrapolated beyond its calibration range. Therefore, a method for extrapolation of CTA calibration curve will be of great practical application. In this paper, a novel approach based on the conventional neural network and self-organizing map (SOM) method has been proposed to extrapolate CTA calibration curve for measurement of velocity in the range 0.7-30 m/seconds. Results show that, using this approach for the extrapolation of the CTA calibration curve beyond its upper limit, the standard deviation is about –0.5%, which is acceptable in most cases. Moreover, this approach for the extrapolation of the CTA calibration curve below its lower limit produces standard deviation of about 4.5%, which is acceptable in spirometry applications. Finally, the standard deviation on the whole measurement range (0.7-30 m/s) is about 1.5%. PMID:23724368

  6. A Catalog of 1.5273 um Diffuse Interstellar Bands Based on APOGEE Hot Telluric Calibrators

    NASA Astrophysics Data System (ADS)

    Elyajouri, M.; Monreal-Ibero, A.; Remy, Q.; Lallement, R.

    2016-08-01

    High resolution stellar spectroscopic surveys provide massive amounts of diffuse interstellar bands (DIBs) measurements. Data can be used to study the distribution of the DIB carriers and those environmental conditions that favor their formation. In parallel, recent studies have also proved that DIBs extracted from stellar spectra constitute new tools for building the 3D structure of the Galactic interstellar medium (ISM). The amount of details on the structure depends directly on the quantity of available lines of sight. Therefore there is a need to construct databases of high-quality DIB measurements as large as possible. We aim at providing the community with a catalog of high-quality measurements of the 1.5273 μm DIB toward a large fraction of the Apache Point Observatory Galactic Evolution Experiment (APOGEE) hot stars observed to correct for the telluric absorption and not used for ISM studies so far. This catalog would complement the extensive database recently extracted from the APOGEE observations and used for 3D ISM mapping. We devised a method to fit the stellar continuum of the hot calibration stars and extracted the DIB from the normalized spectrum. Severe selection criteria based on the absorption characteristics are applied to the results. In particular limiting constraints on the DIB widths and Doppler shifts are deduced from the H i 21 cm measurements, following a new technique of decomposition of the emission spectra. From ˜16,000 available hot telluric spectra we have extracted ˜6700 DIB measurements and their associated uncertainties. The statistical properties of the extracted absorptions are examined and our selection criteria are shown to provide a robust dataset. The resulting catalog contains the DIB total equivalent widths, central wavelengths and widths. We briefly illustrate its potential use for the stellar and interstellar communities.

  7. Hot hollow cathode gun assembly

    DOEpatents

    Zeren, J.D.

    1983-11-22

    A hot hollow cathode deposition gun assembly includes a hollow body having a cylindrical outer surface and an end plate for holding an adjustable heat sink, the hot hollow cathode gun, two magnets for steering the plasma from the gun into a crucible on the heat sink, and a shutter for selectively covering and uncovering the crucible.

  8. Hot corrosion studies of four nickel-base superalloys - B-1900, NASA-TRW VIA, 713C and IN738

    NASA Technical Reports Server (NTRS)

    Fryburg, G. C.; Kohl, F. J.; Stearns, C. A.

    1976-01-01

    The susceptibility to hot corrosion of four nickel-base superalloys has been studied at 900 and 1000 C in one atmosphere of slowly flowing oxygen. Hot corrosion was induced by coating the samples with known doses of Na2SO4 and oxidizing the coated samples isothermally on a sensitive microbalance. In order of decending susceptibility to hot corrosion, these alloys were ranked: B-1900, 713C, NASA-TRW VIA, IN738. This order corresponds to the order of decreasing molybdenum content of the alloys. Chemical evidence for B-1900 indicates that hot corrosion is instigated by acid fluxing of the protective Al2O3 coating by MoO3.

  9. Model-based auralizations of violin sound trends accompanying plate-bridge tuning or holding.

    PubMed

    Bissinger, George; Mores, Robert

    2015-04-01

    To expose systematic trends in violin sound accompanying "tuning" only the plates or only the bridge, the first structural acoustics-based model auralizations of violin sound were created by passing a bowed-string driving force measured at the bridge of a solid body violin through the dynamic filter (DF) model radiativity profile "filter" RDF(f) (frequency-dependent pressure per unit driving force, free-free suspension, anechoic chamber). DF model auralizations for the more realistic case of a violin held/played in a reverberant auditorium reveal that holding the violin greatly diminishes its low frequency response, an effect only weakly compensated for by auditorium reverberation.

  10. Architectural Blueprint for Plate Boundary Observatories based on interoperable Data Management Platforms

    NASA Astrophysics Data System (ADS)

    Kerschke, D. I.; Häner, R.; Schurr, B.; Oncken, O.; Wächter, J.

    2014-12-01

    Interoperable data management platforms play an increasing role in the advancement of knowledge and technology in many scientific disciplines. Through high quality services they support the establishment of efficient and innovative research environments. Well-designed research environments can facilitate the sustainable utilization, exchange, and re-use of scientific data and functionality by using standardized community models. Together with innovative 3D/4D visualization, these concepts provide added value in improving scientific knowledge-gain, even across the boundaries of disciplines. A project benefiting from the added value is the Integrated Plate boundary Observatory in Chile (IPOC). IPOC is a European-South American network to study earthquakes and deformation at the Chilean continental margin and to monitor the plate boundary system for capturing an anticipated great earthquake in a seismic gap. In contrast to conventional observatories that monitor individual signals only, IPOC captures a large range of different processes through various observation methods (e.g., seismographs, GPS, magneto-telluric sensors, creep-meter, accelerometer, InSAR). For IPOC a conceptual design has been devised that comprises an architectural blueprint for a data management platform based on common and standardized data models, protocols, and encodings as well as on an exclusive use of Free and Open Source Software (FOSS) including visualization components. Following the principles of event-driven service-oriented architectures, the design enables novel processes by sharing and re-using functionality and information on the basis of innovative data mining and data fusion technologies. This platform can help to improve the understanding of the physical processes underlying plate deformations as well as the natural hazards induced by them. Through the use of standards, this blueprint can not only be facilitated for other plate observing systems (e.g., the European Plate

  11. Construction and biomechanical properties of polyaxial self-locking anatomical plate based on the geometry of distal tibia.

    PubMed

    Liang, Weiguo; Ye, Weixiong; Ye, Dongping; Zhou, Ziqiang; Chen, Zhiguang; Li, Aiguo; Xie, Zong-Han; Zhang, Lihai; Xu, Jiake

    2014-01-01

    In order to provide scientific and empirical evidence for the clinical application of the polyaxial self-locking anatomical plate, 80 human tibias from healthy adults were scanned by spiral CT and their three-dimensional images were reconstructed using the surface shaded display (SSD) method. Firstly, based on the geometric data of distal tibia, a polyaxial self-locking anatomical plate for distal tibia was designed and constructed. Biomechanical tests were then performed by applying axial loading, 4-point bending, and axial torsion loading on the fracture fixation models of fresh cadaver tibias. Our results showed that variation in twisting angles of lateral tibia surface was found in various segments of the distal tibia. The polyaxial self-locking anatomical plate was constructed based on the geometry of the distal tibia. Compared to the conventional anatomical locking plate, the polyaxial self-locking anatomical plate of the distal tibia provides a better fit to the geometry of the distal tibia of the domestic population, and the insertion angle of locking screws can be regulated up to 30°. Collectively, this study assesses the geometry of the distal tibia and provides variable locking screw trajectory to improve screw-plate stability through the design of a polyaxial self-locking anatomical plate.

  12. Hot roller embossing system equipped with a temperature margin-based controller

    SciTech Connect

    Kim, Seyoung Son, Youngsu; Lee, Sunghee; Ham, Sangyong; Kim, Byungin

    2014-08-15

    A temperature control system was proposed for hot roller embossing. The roll surface was heated using induction coils and cooled with a circulating chilled water system. The temperature of the roll surface was precisely controlled by a temperature margin-based control algorithm that we developed. Implementation of the control system reduced deviations in the roll surface temperature to less than ±2 °C. The tight temperature control and the ability to rapidly increase and decrease the roll temperature will allow optimum operating parameters to be developed quickly. The temperature margin-based controller could also be used to optimize the time course of electrical power and shorten the cooling time by choosing an appropriate temperature margin, possibly for limited power consumption. The chiller-equipped heating roll with the proposed control algorithm is expected to decrease the time needed to determine the optimal embossing process.

  13. Sentiment Diffusion of Public Opinions about Hot Events: Based on Complex Network

    PubMed Central

    Hao, Xiaoqing; An, Haizhong; Zhang, Lijia; Li, Huajiao; Wei, Guannan

    2015-01-01

    To study the sentiment diffusion of online public opinions about hot events, we collected people’s posts through web data mining techniques. We calculated the sentiment value of each post based on a sentiment dictionary. Next, we divided those posts into five different orientations of sentiments: strongly positive (P), weakly positive (p), neutral (o), weakly negative (n), and strongly negative (N). These sentiments are combined into modes through coarse graining. We constructed sentiment mode complex network of online public opinions (SMCOP) with modes as nodes and the conversion relation in chronological order between different types of modes as edges. We calculated the strength, k-plex clique, clustering coefficient and betweenness centrality of the SMCOP. The results show that the strength distribution obeys power law. Most posts’ sentiments are weakly positive and neutral, whereas few are strongly negative. There are weakly positive subgroups and neutral subgroups with ppppp and ooooo as the core mode, respectively. Few modes have larger betweenness centrality values and most modes convert to each other with these higher betweenness centrality modes as mediums. Therefore, the relevant person or institutes can take measures to lead people’s sentiments regarding online hot events according to the sentiment diffusion mechanism. PMID:26462230

  14. Hot Deformation Processing Map and Microstructural Evaluation of the Ni-Based Superalloy IN-738LC

    NASA Astrophysics Data System (ADS)

    Sajjadi, S. A.; Chaichi, A.; Ezatpour, H. R.; Maghsoudlou, A.; Kalaie, M. A.

    2016-04-01

    Hot deformation behavior of the Ni-based superalloy IN-738LC was investigated by means of hot compression tests over the temperature range of 1000-1200 °C and strain rate range of 0.01-1 s-1. The obtained peak flow stresses were related to strain rate and temperature through the hyperbolic sine equation with activation energy of 950 kJ/mol. Dynamic material model was used to obtain the processing map of IN-738LC. Analysis of the microstructure was carried out in order to study each domain's characteristic represented by the processing map. The results showed that dynamic recrystallization occurs in the temperature range of 1150-1200 °C and strain rate of 0.1 s-1 with the maximum power dissipation efficiency of 35%. The unstable domain was exhibited in the temperature range of 1000-1200 °C and strain rate of 1 s-1 on the occurrence of severe deformation bands and grain boundary cracking.

  15. FEA Based Tool Life Quantity Estimation of Hot Forging Dies Under Cyclic Thermo-Mechanical Loads

    NASA Astrophysics Data System (ADS)

    Behrens, B.-A.; Bouguecha, A.; Schäfer, F.; Hadifi, T.

    2011-01-01

    Hot forging dies are exposed during service to a combination of cyclic thermo-mechanical, tribological and chemical loads. Besides abrasive and adhesive wear on the die surface, fatigue crack initiation with subsequent fracture is one of the most frequent causes of failure. In order to extend the tool life, the finite element analysis (FEA) may serve as a means for process design and process optimisation. So far the FEA based estimation of the production cycles until initial cracking is limited as tool material behaviour due to repeated loading is not captured with the required accuracy. Material models which are able to account for cyclic effects are not verified for the fatigue life predictions of forging dies. Furthermore fatigue properties from strain controlled fatigue tests of relevant hot work steels are to date not available to allow for a close-to-reality fatigue life prediction. Two industrial forging processes, where clear fatigue crack initiation has been observed are considered for a fatigue analysis. For this purpose the relevant tool components are modelled with elasto-plastic material behaviour. The predicted sites, where crack initiation occurs, agree with the ones observed on the real die component.

  16. Microfluidic flowmeter based on micro "hot-wire" sandwiched Fabry-Perot interferometer.

    PubMed

    Li, Ying; Yan, Guofeng; Zhang, Liang; He, Sailing

    2015-04-06

    We present a compact microfluidic flowmeter based on Fabry-Perot interferometer (FPI). The FPI was composed by a pair of fiber Bragg grating reflectors and a micro Co(2+)-doped optical fiber cavity, acting as a "hot-wire" sensor. Microfluidic channels made from commercial silica capillaries were integrated with the FPIs on a chip to realize flow-rate sensing system. By utilizing a tunable pump laser with wavelength of 1480 nm, the proposed flowmeter was experimentally demonstrated. The flow rate of the liquid sample is determined by the induced resonance wavelength shift of the FPI. The effect of the pump power, microfluidic channel scale and temperature on the performance of our flowmeter was investigated. The dynamic response was also measured under different flow-rate conditions. The experimental results achieve a sensitivity of 70 pm/(μL/s), a dynamic range up to 1.1 μL/s and response time in the level of seconds, with a spatial resolution ~200 μm. Such good performance renders the sensor a promising supplementary component in microfluidic biochemical sensing system. Furthermore, simulation modal was built up to analyze the heat distribution of the "hot-wire" cavity and optimize the FPI structure as well.

  17. The use of polyolefins-based hot melts for wood bonding

    NASA Astrophysics Data System (ADS)

    Kajaks, J. A.; Bakradze, G. G.; Viksne, A. V.; Reihmane, S. A.; Kalnins, M. M.; Krutohvostov, R.

    2009-11-01

    The shear strength of three-layer birch veneer/polyolefin/birch veneer lap joints has been investigated. It was found that the optimum technological parameters for producing three-layer laminated systems (plywood) at 180°C were a pressure time of 1-3 min (plus 3-min preheating) and pressure of 5-10 MPa. All the systems investigated exhibited relatively high values of shear strength, which were higher than those of the industrially produced plywood based on phenol-formaldehyde glues (3.5-5 MPa). It is shown that the use of interfacial modifiers can increase the shear strength by 50% compared with its initial values. The high shear resistance is explained by the high mechanical adhesion between the hot melts and the wood substrate. After a prolonged moisture influence (70 days at relative air humidity of 80%), all the systems investigated showed a considerable (up to 25%) increase in the shear strength. This can be explained by swelling of birch veneer, which gives rise to additional resistance forces between the hot melt and the substrate.

  18. Case-based reasoning(CBR) model for ultra-fast cooling in plate mill

    NASA Astrophysics Data System (ADS)

    Hu, Xiao; Wang, Zhaodong; Wang, Guodong

    2014-11-01

    New generation thermo-mechanical control process(TMCP) based on ultra-fast cooling is being widely adopted in plate mill to product high-performance steel material at low cost. Ultra-fast cooling system is complex because of optimizing the temperature control error generated by heat transfer mathematical model and process parameters. In order to simplify the system and improve the temperature control precision in ultra-fast cooling process, several existing models of case-based reasoning(CBR) model are reviewed. Combining with ultra-fast cooling process, a developed R5 CBR model is proposed, which mainly improves the case representation, similarity relation and retrieval module. Certainty factor is defined in semantics memory unit of plate case which provides not only internal data reliability but also product performance reliability. Similarity relation is improved by defined power index similarity membership function. Retrieval process is simplified and retrieval efficiency is improved apparently by windmill retrieval algorithm. The proposed CBR model is used for predicting the case of cooling strategy and its capability is superior to traditional process model. In order to perform comprehensive investigations on ultra-fast cooling process, different steel plates are considered for the experiment. The validation experiment and industrial production of proposed CBR model are carried out, which demonstrated that finish cooling temperature(FCT) error is controlled within ±25°C and quality rate of product is more than 97%. The proposed CBR model can simplify ultra-fast cooling system and give quality performance for steel product.

  19. INL HIP Plate Fabrication

    SciTech Connect

    B. H. Park; C. R. Clark; J. F. Jue

    2010-02-01

    This document outlines the process used to bond monolithic fuel plates by Hot Isostatic Pressing (HIP). This method was developed at Idaho National Laboratory (INL) for the Reduced Enrichment for Research and Test Reactors (RERTR) program. These foils have been used in a number of irradiation experiments in support of the United States Global Threat Reduction Initiative (GTRI) program.

  20. Factors Affecting the Morphology of Pb-Based Glass Frit Coated with Ag Material Prepared by Electroless Silver Plating

    NASA Astrophysics Data System (ADS)

    Huang, Bei; Gan, Weiping; Zhou, Jian; Li, Yingfen; Lin, Tao; Liu, Xiaogang

    2014-05-01

    Pb-based glass frit coated with nanosilver material for Si solar cell applications has been directly prepared by electroless silver plating. Activation of the glass frit was accomplished by using glycol, with the aim of reducing the silver ions to elemental silver on the surface of the glass frit. Electroless silver plating onto the glass frit was successfully realized using two kinds of electroless plating bath. However, the morphology of the composite powder greatly affected the modality, sheet resistance, series resistance, and photoelectric conversion efficiency of the conducting silver films. We found that the activation temperature affected the number and distribution of silver nanoparticles. Meanwhile, the average grain size of the silver particles and the silver content in the Pb-based glass frit coated with Ag material could be controlled by adjusting the pH value and loading capacity, respectively, during plating.

  1. A location method for vehicle license plate based on color image and black-white texture

    NASA Astrophysics Data System (ADS)

    Li, Gang; Liu, Chang; He, Mingquan; Huang, Xiyue

    2007-12-01

    This paper presents an effective location algorithm employing color features and black-white texture analysis of the image to extract a vehicle license plate from a complicated background image. According to the background color of the license plate in RGB spaces, we transform the RGB image into a grayscale image as strengthening the color of the license plate, and partition the intensity image to obtain a binary image which can outstand the license plate part. We leach away the color which is similar to the license plate by analyzing the texture characteristic. The test shows that this location method can hardly be influenced by all of the factors including illumination, license plate position, license plate size, license plate angle, car position, image background and so on. Meanwhile, it can gain a high speed, better effects and a wide application area.

  2. Bead Based Proteome Enrichment Enhances Features of the Protein Elution Plate (PEP) for Functional Proteomic Profiling

    PubMed Central

    Wang, Xing; Davies, Michael; Roy, Swapan; Kuruc, Matthew

    2015-01-01

    A novel functional proteomics technology called PEP(Protein Elution Plate) was developed to separate complex proteomes from natural sources and analyze protein functions systematically. The technology takes advantage of the powerful resolution of two-dimensional gel electrophoresis (2-D Gels). The modification of electrophoretic conditions in combination with a high-resolution protein elution plate supports the recovery of functionally active proteins. As 2DE(2-Dimensional Electrophoresis) resolution can be limited by protein load, we investigated the use of bead based enrichment technologies, called AlbuVoid™ and KinaSorb™ to determine their effect on the proteomic features which can be generated from the PEP platform. Using a variety of substrates and enzyme activity assays, we report on the benefits of combining bead based enrichment to improve the signal report and the features generated for Hexokinase, Protein Kinase, Protease, and Alkaline Phosphatase activities. As a result, the PEP technology allows systematic analysis of large enzyme families and can build a comprehensive picture of protein function from a complex proteome, providing biological insights that could otherwise not be observed if only protein abundances were analyzed. PMID:28248280

  3. Crack Identification of Cantilever Plates Based on a Kriging Surrogate Model.

    PubMed

    Gao, Haiyang; Guo, Xinglin; Ouyang, Huajiang; Han, Fang

    2013-10-01

    This work presents an effective method to identify the tip locations of an internal crack in cantilever plates based on a Kriging surrogate model. Samples of varying crack parameters (tip locations) and their corresponding root mean square (RMS) of random responses are used to construct the initial Kriging surrogate model. Moreover, the pseudo excitation method (PEM) is employed to speed up the spectral analysis. For identifying crack parameters based on the constructed Kriging model, a robust stochastic particle swarm optimization (SPSO) algorithm is adopted for enhancing the global searching ability. To improve the accuracy of the surrogate model without using extensive samples, a small number of samples are first used. Then an optimal point-adding process is carried out to reduce computational cost. Numerical studies of a cantilever plate with an internal crack are performed. The effectiveness and efficiency of this method are demonstrated by the identified results. The effect of initial sampling size on the precision of the identified results is also investigated.

  4. Metallurgical evaluation of SRAM II/SRAM A programmer base plates

    SciTech Connect

    Damkroger, B.K.; Maguire, M.C.; Robino, C.V.

    1993-05-01

    Ten MC4073/4369 programmer base plates were analyzed. This component, a programmer base plate for the SRAM II (and later the SRAM A), is specified as a Grade C quality casting made of aluminum Alloy A356, heat treated to the T6 condition. A concern was expressed regarding the choice of an A356 casting for this application, given the complexity and severity of the loading environment. Preliminary tests and analyses suggested that the design was adequate, but noted the uncertainty involved in a number of their underlying assumptions. The uncertainty was compounded by the discovery that the casting used in the original series of mechanical tests failed. In this investigation, several production castings were examined and found to be of a quality superior to that required under current specifications. Their defect content and microstructure were studied and compared with published data to establish a mechanical property data base. The data base was supplemented with a series of X-direction static tests, which characterized the loading environment and measured the overall casting performance. It was found that the mechanical properties of the supplied castings were adequate for the anticipated X-direction loading environment, but the component is not over-designed. The established data base further indicates that a reduction in casting quality to the allowable level could result in failure of the component. Recommendations were made including (1) change the component specification to require higher casting quality in highly stressed areas, (2) supplement the inspection procedures to ensure adequate quality in critical regions, (3) alter the component design to reduce the stress levels in the mounting feet, (4) substitute a modified A356 alloy to improve the mechanical properties and their consistency, and (5) more thoroughly establish a data base for the mechanical property consequences of levels and configurations of casting defects.

  5. Microstructural Stability and Hot Deformation of γ- γ'- δ Ni-Base Superalloys

    NASA Astrophysics Data System (ADS)

    Detrois, Martin; Helmink, Randolph C.; Tin, Sammy

    2014-11-01

    Nickel-base superalloys exhibit excellent high-temperature mechanical and physical properties and remain the first choice for structural components in advanced gas turbine engines for the aerospace propulsion and power generation applications. In response to the increasing demand for more efficient solutions and tighter requirements linked to gas turbine technologies, the properties of nickel-base superalloys can be improved by modification of their thermo-mechanical and/or compositional attributes. Recent investigations have revealed the potential use of ternary eutectic γ- γ'- δ Ni-base superalloys in advanced gas turbines due to high temperature mechanical properties that are comparable to state-of-the-art polycrystalline Ni-base superalloys. With properties largely dependent on microstructural strengthening mechanisms, both the composition and thermo-mechanical processing parameters of this novel class of alloys need to be optimized concurrently. The hot deformation characteristics of four γ- γ'- δ Ni-base superalloys with varying levels of Nb were evaluated at temperatures and strain rates between 1353 K and 1433 K (1080 °C and 1160 °C) and 0.01 to 0.001/s, respectively. Evidence of dislocation-based plasticity was observed following deformation at low temperatures and high strain rates, while high temperatures and low strain rates promoted superplasticity in these alloys. The extent of the microstructural changes and the magnitude of the cavitation damage which occurred during deformation was found to vary as a function of the alloy composition.

  6. Process improvement in laser hot wire cladding for martensitic stainless steel based on the Taguchi method

    NASA Astrophysics Data System (ADS)

    Huang, Zilin; Wang, Gang; Wei, Shaopeng; Li, Changhong; Rong, Yiming

    2016-09-01

    Laser hot wire cladding, with the prominent features of low heat input, high energy efficiency, and high precision, is widely used for remanufacturing metal parts. The cladding process, however, needs to be improved by using a quantitative method. In this work, volumetric defect ratio was proposed as the criterion to describe the integrity of forming quality for cladding layers. Laser deposition experiments with FV520B, one of martensitic stainless steels, were designed by using the Taguchi method. Four process variables, namely, laser power ( P), scanning speed ( V s), wire feed rate ( V f), and wire current ( I), were optimized based on the analysis of signal-to-noise (S/N) ratio. Metallurgic observation of cladding layer was conducted to compare the forming quality and to validate the analysis method. A stable and continuous process with the optimum parameter combination produced uniform microstructure with minimal defects and cracks, which resulted in a good metallurgical bonding interface.

  7. Hot, cold, and annual reference atmospheres for Edwards Air Force Base, California (1975 version)

    NASA Technical Reports Server (NTRS)

    Johnson, D. L.

    1975-01-01

    Reference atmospheres pertaining to summer (hot), winter (cold), and mean annual conditions for Edwards Air Force Base, California, are presented from surface to 90 km altitude (700 km for the annual model). Computed values of pressure, kinetic temperature, virtual temperature, and density and relative differences percentage departure from the Edwards reference atmospheres, 1975 (ERA-75) of the atmospheric parameters versus altitude are tabulated in 250 m increments. Hydrostatic and gas law equations were used in conjunction with radiosonde and rocketsonde thermodynamic data in determining the vertical structure of these atmospheric models. The thermodynamic parameters were all subjected to a fifth degree least-squares curve-fit procedure, and the resulting coefficients were incorporated into Univac 1108 computer subroutines so that any quantity may be recomputed at any desired altitude using these subroutines.

  8. High-strength zirconium diboride-based ceramic composites consolidated by low-temperature hot pressing

    NASA Astrophysics Data System (ADS)

    Guo, Shuqi; Kagawa, Yutaka

    2012-08-01

    Two compositions of ZrB2-based ceramic composites containing Si3N4, Al2O3 and Y2O3 have been hot-pressed at different temperatures between 1673 and 1773 K for 60 min in vacuum. The densification behavior of the composites was examined during the sintering process. The microstructures of the composites were characterized by scanning electron microscopy, and the crystalline phases were identified by x-ray diffraction. The effects of Al2O3 and Y2O3 additives on the densification behavior and flexural strength were assessed. A relative density of ˜95% was obtained after sintering at 1723 K or higher temperatures. The microstructures of the composites consisted of (Zr,Y)B2, α-Si3N4 and Y3(Al,Si)5O12 phases. The room-temperature flexural strength increased with the amount of additives and approached 1 GPa.

  9. Long rod penetration test of hot isostatically pressed Ti-based targets

    NASA Astrophysics Data System (ADS)

    Nesterenko, Vitali F.; Indrakanti, Sastry S.; Brar, Singh; Gu, YaBei

    2000-04-01

    Hot Isostatic Pressing (HIP) is one of the most efficient techniques to produce high quality materials from powders. Nevertheless there is a shortage of data on high-strain-rate behavior and penetration resistance of such materials. In this paper the results of penetration test with tungsten (93%) heavy alloy penetrators of solid and porous composite samples of Ti-6Al-4V alloy with different microstructures (Widmanstatten pattern and equiaxed) are presented. Penetration depth for HIPed materials is smaller than in baseline samples of Ti-6Al-4V alloy (forged rod MIL-T-9047G). Composite materials with alumina rods and tubes filled with B4C powders demonstrated a new features of penetration: projectile deflection with self sealing of hole and forced shear localization caused by tubes fracture. The results demonstrate the applicability of HIPing for Ti-based armor materials.

  10. Wind-Based Navigation of a Hot-air Balloon on Titan: A Feasibility Study

    NASA Technical Reports Server (NTRS)

    Furfaro, Roberto; Lunine, Jonathan I.; Elfes, Alberto; Reh, Kim

    2008-01-01

    Current analysis of data streamed back to Earth by the Cassini spacecraft features Titan as one of the most exciting places in the solar system. NASA centers and universities around the US, as well as the European Space Agency, are studying the possibility of sending, as part of the next mission to this giant moon of Saturn, a hot-air balloon (Montgolfier-type) for further and more in-depth exploration. The basic idea would be to design a reliable, semi-autonomous, and yet cheap Montgolfier capable of using continuous flow of waste heat from a power source to lift the balloon and sustain its altitude in the Titan environment. In this paper we study the problem of locally navigating a hot-air balloon in the nitrogen-based Titan atmosphere. The basic idea is to define a strategy (i.e. design of a suitable guidance system) that allows autonomous and semi-autonomous navigation of the balloon using the available (and partial) knowledge of the wind structure blowing on the saturnian satellite surface. Starting from first principles we determined the appropriate thermal and dynamical models describing (a) the vertical dynamics of the balloon and (b) the dynamics of the balloon moving on a vertical plane (2-D motion). Next, various non-linear fuzzy-based control strategies have been evaluated, analyzed and implemented in MATLAB to numerically simulate the capability of the system to simultaneously maintain altitude, as well as a scientifically desirable trajectory. We also looked at the ability of the balloon to perform station keeping. The results of the simulation are encouraging and show the effectiveness of such a system to cheaply and effectively perform semiautonomous exploration of Titan.

  11. Design of plate directional heat transmission structure based on layered thermal metamaterials

    SciTech Connect

    Sun, L. K.; Yu, Z. F.; Huang, J.

    2016-02-15

    Invisibility cloaks based on transformation optics are often closed structures; however, such a structure limits the kinds of objects that can be placed in the cloak. In this work, we adopt a transformation thermodynamics approach to design an “open cloak”, called a plate directional heat transmission structure, which is capable of guiding heat fluxes to the flank region of the metamaterial device. The most fascinating and unique feature of the device is that the lower surface can remain at a lower temperature compared with the SiO{sub 2} aerogel thermal insulation material. Our results are expected to markedly enhance capabilities in thermal protection, thermal-energy utilization, and domains beyond. In addition to the theoretical analysis, the present design is demonstrated in numerical simulations based on finite element calculations.

  12. Iron-based alloy and nitridation treatment for PEM fuel cell bipolar plates

    DOEpatents

    Brady, Michael P [Oak Ridge, TN; Yang, Bing [Oak Ridge, TN; Maziasz, Philip J [Oak Ridge, TN

    2010-11-09

    A corrosion resistant electrically conductive component that can be used as a bipolar plate in a PEM fuel cell application is composed of an alloy substrate which has 10-30 wt. % Cr, 0.5 to 7 wt. % V, and base metal being Fe, and a continuous surface layer of chromium nitride and vanadium nitride essentially free of base metal. A oxide layer of chromium vanadium oxide can be disposed between the alloy substrate and the continuous surface nitride layer. A method to prepare the corrosion resistant electrically conductive component involves a two-step nitridization sequence by exposing the alloy to a oxygen containing gas at an elevated temperature, and subsequently exposing the alloy to an oxygen free nitrogen containing gas at an elevated temperature to yield a component where a continuous chromium nitride layer free of iron has formed at the surface.

  13. ASP (AntiSubmarine Penetrator) base plate redesign and explosive bolt test

    SciTech Connect

    Cole, J.K.; Wolfe, W.P.

    1988-10-01

    This report presents the results of a post-flight investigation of the Rocket Antisubmarine Penetrator (RAP) tests of the AntiSubmarine Penetrator (ASP). It focuses on the cause for the premature deployment of the on-board recovery system and the failure of the base pressure transducers. As a result of the investigation, the base plate of the ASP vehicle was modified to increase its structural stiffness. Also, an instrumented test was conducted to assess the environment that is created when the three explosive bolts are activated to separate the vehicle from the interstage adapter and the rocket booster. The results of this test are presented and discussed. 5 refs., 15 figs.

  14. Adjustable low frequency and broadband metamaterial absorber based on magnetic rubber plate and cross resonator

    NASA Astrophysics Data System (ADS)

    Cheng, Yongzhi; Nie, Yan; Wang, Xian; Gong, Rongzhou

    2014-02-01

    In this paper, the magnetic rubber plate absorber (MRPA) and metamaterial absorber (MA) based on MRP substrate were proposed and studied numerically and experimentally. Based on the characteristic of L-C resonances, experimental results show that the MA composed of cross resonator (CR) embedded single layer MRP could be adjustable easily by changing the wire length and width of CR structure and MRP thickness. Finally, experimental results show that the MA composed of CR-embedded two layers MRP with the total thickness of 2.42 mm exhibit a -10 dB absorption bandwidth from 1.65 GHz to 3.7 GHz, which is 1.86 times wider than the same thickness MRPA.

  15. Nanofocusing of hard X-ray free electron laser pulses using diamond based Fresnel zone plates.

    PubMed

    David, C; Gorelick, S; Rutishauser, S; Krzywinski, J; Vila-Comamala, J; Guzenko, V A; Bunk, O; Färm, E; Ritala, M; Cammarata, M; Fritz, D M; Barrett, R; Samoylova, L; Grünert, J; Sinn, H

    2011-01-01

    A growing number of X-ray sources based on the free-electron laser (XFEL) principle are presently under construction or have recently started operation. The intense, ultrashort pulses of these sources will enable new insights in many different fields of science. A key problem is to provide x-ray optical elements capable of collecting the largest possible fraction of the radiation and to focus into the smallest possible focus. As a key step towards this goal, we demonstrate here the first nanofocusing of hard XFEL pulses. We developed diamond based Fresnel zone plates capable of withstanding the full beam of the world's most powerful x-ray laser. Using an imprint technique, we measured the focal spot size, which was limited to 320 nm FWHM by the spectral band width of the source. A peak power density in the focal spot of 4×10(17)W/cm(2) was obtained at 70 fs pulse length.

  16. Eco-friendly gas mixtures for Resistive Plate Chambers based on tetrafluoropropene and Helium

    NASA Astrophysics Data System (ADS)

    Abbrescia, M.; Benussi, L.; Piccolo, D.; Bianco, S.; Ferrini, M.; Muhammad, S.; Passamonti, L.; Pierluigi, D.; Piccolo, D.; Primavera, F.; Russo, A.; Saviano, G.

    2016-08-01

    Due to the recent restrictions deriving from the application of the Kyoto protocol, the main components of the gas mixtures presently used in the Resistive Plate Chambers systems of the LHC experiments will be most probably phased out of production in the coming years. Identifying possible replacements with the adequate characteristics requires an intense R&D activity, which was recently started, in collaborations with various experiments. Possible new gases have been proposed and are thoroughly investigated. Some tests on one of the most promising candidate—HFO-1234ze, an allotropic form of tetrafluoropropane—have already been reported. Here an innovative approach, based on the use of Helium, to solve the problem related to the high operating voltage needed to operate the chambers with HFO-1234ze based gas mixtures, is discussed and the first results are shown.

  17. Vibrations of Base Plates in Annular Cylindrical Tanks: Theory and Experiments

    NASA Astrophysics Data System (ADS)

    Amabili, M.; Dalpiaz, G.

    1998-02-01

    In this paper, the bulging modes (i.e., modes where the walls oscillate moving the liquid) of the flexible bottom annular plate of an otherwise rigid annular cylindrical container are studied. The tank has a vertical axis and is partially filled with liquid, so that the free surface of the liquid is orthogonal to the tank axis. The volume occupied by the liquid is delimited by two coaxial rigid cylinders and the liquid deformation potential is obtained by using variables separation. First, by using the simplifying hypothesis that the mode shapes of the plates in contact with the liquid (wet modes) are the samein vacuo, the approach based on the non-dimensionalized added virtual mass incremental (NAVMI) factor is applied, so that all numerical computations can be made non-dimensional. Second, the accuracy of this method is checked by using the Rayleigh-Ritz method, which removes the restrictive hypothesis on the wet mode shapes. Finally, several experimental modal analyses were performed on two different test tanks filled with different water levels in order to verify the accuracy of the theoretical results.

  18. Focal length measurement based on Fresnel diffraction from a phase plate.

    PubMed

    Dashtdar, Masoomeh; Mohammad-Ali Hosseini-Saber, S

    2016-09-10

    A method based on the Fresnel diffraction of light from the phase step is introduced for measuring effective focal length (EFL) and back focal length (BFL) of optical imaging systems. It is shown that, as a transparent plane-parallel plate is illuminated at a boundary region by a monochromatic beam of light, Fresnel diffraction occurs because of the abrupt change in phase imposed by the finite change in refractive index at the plate boundary. Variation of the incident angle in a convergent (or divergent) beam of light causes the periodic intensity along the central fringe of the diffraction pattern. The measurement of the extrema position of the intensity distribution accurately provides the EFL and BFL. The technique is easy to apply and can measure a wide range of both positive and negative focal lengths. The measuring setup can be very compact with low mechanical and optical noises. As examples of this technique, the EFLs of five different lenses are experimentally obtained. The results are quite consistent with the values indicated by the lens manufacturer.

  19. Hyaluronan is essential for the expansion of the cranial base growth plates.

    PubMed

    Gakunga, P T; Kuboki, Y; Opperman, L A

    2000-01-01

    Exquisite control of chondrocyte function in the zone of hypertrophy results in expansive growth of cartilaginous growth plates, and is a prerequisite for normal skeletal lengthening. We hypothesize that hyaluronan-mediated hydrostatic pressure causes lacunae expansion in the zone of hypertrophy; an important mechanism in cartilaginous growth plate and associated skeletal expansion. The role of hyaluronan and CD44 in this mechanism was studied using organ culture of the bipolar cranial base synchondroses. Hyaluronan was present in the hypertrophic zones, pericellular to the hypertrophic chondrocytes, while no hyaluronan was detected in the resting, proliferating and maturing zones. This localization of hyaluronan was associated with increased lacunae size, suggesting that chondrocytes deposit and retain pericellular hyaluronan as they mature. In comparison, Toluidine Blue staining was associated with the territorial matrix. Hyaluronidase, the hyaluronan-degrading enzyme, and CD44, the receptor for hyaluronan which also participates in the uptake and degradation of hyaluronan, were co-localized within the zone of ossification. This pattern of expression suggests that cells in the early zone of ossification internalize and degrade hyaluronan through a CD44-mediated mechanism. Treatment of the cultured segments with either Streptomyces hyaluronidase or hyaluronan hexasaccharides inhibited lacunae expansion. These observations demonstrate that hyaluronan-mediated mechanisms play an important role in controlling normal skeletal lengthening.

  20. Canadian Arctic Plate Reconstructions based on revised geological and geophysical data

    NASA Astrophysics Data System (ADS)

    Torsvik, Trond H.; Gaina, Carmen

    2015-04-01

    We present a revised rifting and seafloor spreading history around Greenland based on geological and geophysical constraints. Palaeomagnetic data from (i) Neoproterozoic dykes and sills in North America, NW Greenland, Devon and SW Ellesmere (Franklin and Clarence Head), (ii) Early Permian volcanism (Esayoo unit) in Ellesmere and (iii) Cretaceous volcanism and intrusive activity (Isachsen and Strandfjord Formations) in Axel Heiberg and Ellesmere have also been re-evaluated and used to develop a new Canadian Arctic plate model from Silurian to Paleogene times. We have tentatively divided the Canadian Arctic into seven tectonic units, including Pearya, which accreted to the northern sectors of Ellesmere and Axel Heiberg islands as part of the mid-Silurian Caledonide Orogeny. The Canadian Arctic was variable deformed during the Late Devonian Ellesmere and the Tertiary Eurekean events, the latter including c. 250 km of shortening and ultimately amalgamating all the Canadian Arctic units in the Late Eocene. Two of the units, Devon and SW Ellesmere must have been closely tied to NW Greenland (the 'Greenland Plate') in order to minimize Palaeocene-Eocene deformation across the Nares Strait during Labrador Sea and Baffin Bay seafloor spreading. We model 100 and 60 km of Late Cretaceous-Eocene transtension/extension in the Lancaster and Jones Sounds but in order to avoid too much continental overlap between Devon and North America (Lancaster Sound) we must include 150 km of pure strike-slip faulting along the Nares Strait.

  1. An assessment of four-noded plate finite elements based on a generalized third-order theory

    NASA Astrophysics Data System (ADS)

    Averill, R. C.; Reddy, J. N.

    1992-06-01

    Plate finite elements based on the generalized third-order theory of Reddy and the first-order shear deformation theory are analyzed and compared on the basis of thick and thin plate modeling behavior, distortion sensitivity, overall accuracy, reliability, and efficiency. In particular, several four-noded Reddy-type elements and the nine-noded Lagrangian and heterosis (Mindlin-type) plate elements are analyzed to assess their behavior in bending, vibration, and stability of isotropic and laminated composite plates. A four-noded Reddy-type element is identified which is free of all spurious stiffness and zero energy modes, computationally efficient, and suitable for use in any general-purpose finite element program.

  2. An assessment of four-noded plate finite elements based on a generalized third-order theory

    NASA Technical Reports Server (NTRS)

    Averill, R. C.; Reddy, J. N.

    1992-01-01

    Plate finite elements based on the generalized third-order theory of Reddy and the first-order shear deformation theory are analyzed and compared on the basis of thick and thin plate modeling behavior, distortion sensitivity, overall accuracy, reliability, and efficiency. In particular, several four-noded Reddy-type elements and the nine-noded Lagrangian and heterosis (Mindlin-type) plate elements are analyzed to assess their behavior in bending, vibration, and stability of isotropic and laminated composite plates. A four-noded Reddy-type element is identified which is free of all spurious stiffness and zero energy modes, computationally efficient, and suitable for use in any general-purpose finite element program.

  3. A reactive burn model for shock initiation in a PBX: scaling and separability based on the hot spot concept

    SciTech Connect

    Show, Milton S; Menikoff, Ralph

    2010-01-01

    In the formulation of a reactive burn model for shock initiation, we endeavor to incorporate a number of effects based on the underlying physical concept of hot spot ignition followed by the growth of reaction due to diverging deflagration fronts. The passage of a shock front sets the initial condition for reaction, leading to a fraction of the hot spots that completely burn while others will quench. The form of the rate model is chosen to incorporate approximations based on the physical picture. In particular, the approximations imply scaling relations that are then used to mathematically separate various contributions. That is, the model is modular and refinements can be applied separately without changing the other contributions. For example, the effect of initial temperature, porosity, etc. predominantly enter the characterization of the non-quenching hot spot distribution. A large collection of velocity gauge data is shown to be well represented by the model with a very small number of parameters.

  4. Detection of ligand binding hot spots on protein surfaces via fragment-based methods: application to DJ-1 and glucocerebrosidase

    SciTech Connect

    Landon, Melissa R.; Lieberman, Raquel L.; Hoang, Quyen Q.; Ju, Shulin; Caaveiro, Jose M.M.; Orwig, Susan D.; Kozakov, Dima; Brenke, Ryan; Chuang, Gwo-Yu; Beglov, Dmitry; Vajda, Sandor; Petsko, Gregory A.; Ringe, Dagmar

    2010-08-04

    The identification of hot spots, i.e., binding regions that contribute substantially to the free energy of ligand binding, is a critical step for structure-based drug design. Here we present the application of two fragment-based methods to the detection of hot spots for DJ-1 and glucocerebrosidase (GCase), targets for the development of therapeutics for Parkinson's and Gaucher's diseases, respectively. While the structures of these two proteins are known, binding information is lacking. In this study we employ the experimental multiple solvent crystal structures (MSCS) method and computational fragment mapping (FTMap) to identify regions suitable for the development of pharmacological chaperones for DJ-1 and GCase. Comparison of data derived via MSCS and FTMap also shows that FTMap, a computational method for the identification of fragment binding hot spots, is an accurate and robust alternative to the performance of expensive and difficult crystallographic experiments.

  5. Fabrication of lotus-leaf-like superhydrophobic surfaces via Ni-based nano-composite electro-brush plating

    NASA Astrophysics Data System (ADS)

    Liu, Hongtao; Wang, Xuemei; Ji, Hongmin

    2014-01-01

    Superhydrophobic surface has become a research hot topic in recent years due to its excellent performance and wide application prospect. This paper investigates the method to fabricate superhydrophobic surface on carbon steel substrate via two-layer nano-composite electro-brush plating and subsequent surface modification with low free energy materials. The hydrophobic properties of as-prepared coatings were characterized by a water sliding angle (SA) and a water contact angle (CA) measured by the Surface tension instrument. A Scanning electron microscope was used to analyze the surface structure of plating coatings. Anti-corrosion performance of the superhydrophobic coating was characterized by a potentiodynamic polarization curve measured by the Electrochemical workstation. The research result shows that: the superhydrophobic structure can be successfully prepared by plating nano-C/Ni and nano-Cu/Ni two-layer coating on carbon steel substrate under appropriate technology and has similarity with lotus-leaf-like micro/nano composite structure; the contact angle of the as-prepared superhydrophobic coating can be up to 155.5°, the sliding angle is 5°; the coating has better anti-corrosion performance compared with substrate.

  6. High-k dielectrics based field plate edge termination engineering in 4H-SiC Schottky diode

    NASA Astrophysics Data System (ADS)

    Shankar, Bhawani; Gupta, Sanjeev K.; Taube, William R.; Akhtar, J.

    2016-12-01

    This paper develops a deep insight into the behaviour of high-k dielectric-based field plate on Ni/4H-SiC Schottky diode. It tries to explain the mechanism by which high-k materials outperform silicon dioxide, when used under the field plate. Phenomena like modulation of field enhancement factor, reshaping of equipotential contours and expansion of depletion region while maintaining fixed depletion ratio (length/width = 2.3) helps to understand the electrical behaviour of high-k dielectric-based field plate. High-k materials relaxed the equipotential contours under the field plate edge which resulted in electric field reduction up to 88% and significant drop from 6.6 to 2.2 in field enhancement factor at device edges. The study considers the field plate of different dielectrics (SiO2, Si3N4, Al203, HfO2) and in each case, analytically explores the optimisation of field plate parameters (overlap length and dielectric thickness, dielectric constant). All the investigations have been done using numerical simulations on calibrated setup.

  7. Structural insights of microbial community of Deulajhari (India) hot spring using 16s-rRNA based metagenomic sequencing.

    PubMed

    Singh, Archana; Subudhi, Enketeswara

    2016-03-01

    Insights about the distribution of the microbial community prove to be the major goal of understanding microbial ecology which remains to be fully deciphered. Hot springs being hub for the thermophilic microbiota attract the attention of the microbiologists. Deulajhari hot spring cluster is located in the Angul district of Odisha. Covered within a wooded area, Deulajhari hot spring is also fed by the plant litter resulting in a relatively high amount of total organic content (TOC). For the first time, Illumina sequencing based biodiversity analysis of microbial composition is studied through amplicon metagenome sequencing of 16s rRNA targeting V3-V4 region using metagenomic DNA from the hot spring sediment. Over 28 phyla were detected through the amplicon metagenome sequencing of which the most dominating phyla at the existing physiochemical parameters like; temperature 69 °C, pH 8.09, electroconductivity 0.025 dSm(- 1) and total organic carbon 0.356%, were Proteobacteria (88.12%), Bacteriodetes (10.76%), Firmicutes (0.35%), Spirochetes (0.18%) and chloroflexi (0.11%). Approximately 713 species were observed at the above physiochemical parameters. The analysis of the metagenome provides the quantitative insights into microbial populations based on the sequence data in Deulajhari hot spring. Metagenome sequence is deposited to SRA database which is available at NCBI with accession no. SRX1459736.

  8. Microbial community analysis of a coastal hot spring in Kagoshima, Japan, using molecular- and culture-based approaches.

    PubMed

    Nishiyama, Minako; Yamamoto, Shuichi; Kurosawa, Norio

    2013-08-01

    Ibusuki hot spring is located on the coastline of Kagoshima Bay, Japan. The hot spring water is characterized by high salinity, high temperature, and neutral pH. The hot spring is covered by the sea during high tide, which leads to severe fluctuations in several environmental variables. A combination of molecular- and culture-based techniques was used to determine the bacterial and archaeal diversity of the hot spring. A total of 48 thermophilic bacterial strains were isolated from two sites (Site 1: 55.6°C; Site 2: 83.1°C) and they were categorized into six groups based on their 16S rRNA gene sequence similarity. Two groups (including 32 isolates) demonstrated low sequence similarity with published species, suggesting that they might represent novel taxa. The 148 clones from the Site 1 bacterial library included 76 operational taxonomy units (OTUs; 97% threshold), while 132 clones from the Site 2 bacterial library included 31 OTUs. Proteobacteria, Bacteroidetes, and Firmicutes were frequently detected in both clone libraries. The clones were related to thermophilic, mesophilic and psychrophilic bacteria. Approximately half of the sequences in bacterial clone libraries shared <92% sequence similarity with their closest sequences in a public database, suggesting that the Ibusuki hot spring may harbor a unique and novel bacterial community. By contrast, 77 clones from the Site 2 archaeal library contained only three OTUs, most of which were affiliated with Thaumarchaeota.

  9. Kinetics of MN based sorbents for hot coal gas. Quarterly report, September--December 1996

    SciTech Connect

    1996-12-31

    Manganese-based sorbents have been investigated for the removal of hydrogen sulfide (the primary sulfur bearing compound) from hot coal gases prior to its use in combined cycle turbines. Four formulations of Mn-based sorbents were tested in an ambient-pressure fixed-bed reactor to determine steady state H{sub 2}S concentrations, breakthrough times and effectiveness of the sorbent when subjected to cyclic sulfidation and regeneration testing. In a previous report, the sulfidation results were presented. Manganese-based sorbents with molar ratios > 1:1 Mn:Substrate were effective in reducing the H{sub 2}S concentration in simulated coal gases to less than 100 ppmv over five cycles. Actual breakthrough time for formulation C6-2-1100 was as high as 73% of breakthrough time based on wt% Mn in sorbent. In this report, the regeneration results will be presented. Regeneration tests determined that loaded pellets can be fully regenerated in air/steam mixture at 750{degrees}C with minimal sulfate formation. 16 refs., 9 figs., 5 tabs.

  10. The Association of Hot Red Chili Pepper Consumption and Mortality: A Large Population-Based Cohort Study.

    PubMed

    Chopan, Mustafa; Littenberg, Benjamin

    2017-01-01

    The evidence base for the health effects of spice consumption is insufficient, with only one large population-based study and no reports from Europe or North America. Our objective was to analyze the association between consumption of hot red chili peppers and mortality, using a population-based prospective cohort from the National Health and Nutritional Examination Survey (NHANES) III, a representative sample of US noninstitutionalized adults, in which participants were surveyed from 1988 to 1994. The frequency of hot red chili pepper consumption was measured in 16,179 participants at least 18 years of age. Total and cause-specific mortality were the main outcome measures. During 273,877 person-years of follow-up (median 18.9 years), a total of 4,946 deaths were observed. Total mortality for participants who consumed hot red chili peppers was 21.6% compared to 33.6% for those who did not (absolute risk reduction of 12%; relative risk of 0.64). Adjusted for demographic, lifestyle, and clinical characteristics, the hazard ratio was 0.87 (P = 0.01; 95% Confidence Interval 0.77, 0.97). Consumption of hot red chili peppers was associated with a 13% reduction in the instantaneous hazard of death. Similar, but statistically nonsignificant trends were seen for deaths from vascular disease, but not from other causes. In this large population-based prospective study, the consumption of hot red chili pepper was associated with reduced mortality. Hot red chili peppers may be a beneficial component of the diet.

  11. The Association of Hot Red Chili Pepper Consumption and Mortality: A Large Population-Based Cohort Study

    PubMed Central

    Chopan, Mustafa

    2017-01-01

    The evidence base for the health effects of spice consumption is insufficient, with only one large population-based study and no reports from Europe or North America. Our objective was to analyze the association between consumption of hot red chili peppers and mortality, using a population-based prospective cohort from the National Health and Nutritional Examination Survey (NHANES) III, a representative sample of US noninstitutionalized adults, in which participants were surveyed from 1988 to 1994. The frequency of hot red chili pepper consumption was measured in 16,179 participants at least 18 years of age. Total and cause-specific mortality were the main outcome measures. During 273,877 person-years of follow-up (median 18.9 years), a total of 4,946 deaths were observed. Total mortality for participants who consumed hot red chili peppers was 21.6% compared to 33.6% for those who did not (absolute risk reduction of 12%; relative risk of 0.64). Adjusted for demographic, lifestyle, and clinical characteristics, the hazard ratio was 0.87 (P = 0.01; 95% Confidence Interval 0.77, 0.97). Consumption of hot red chili peppers was associated with a 13% reduction in the instantaneous hazard of death. Similar, but statistically nonsignificant trends were seen for deaths from vascular disease, but not from other causes. In this large population-based prospective study, the consumption of hot red chili pepper was associated with reduced mortality. Hot red chili peppers may be a beneficial component of the diet. PMID:28068423

  12. Hot Corrosion of Nickel-Base Alloys in Biomass-Derived Fuel Simulated Atmosphere

    SciTech Connect

    Leyens, C.; Pint, B.A.; Wright, I.G.

    1999-02-28

    Biomass fuels are considered to be a promising renewable source of energy. However, impurities present in the fuel may cause corrosion problems with the materials used in the hot sections of gas turbines and only limited data are available so far. As part of the Advanced Turbine Systems Program initiated by the U.S. Department of Energy, the present study provides initial data on the hot corrosion resistance of different nickel-base alloys against sodium sulfate-induced corrosion as a baseline, and against salt compositions simulating biomass-derived fuel deposits. Single crystal nickel-superalloy Rene N5, a cast NiCrAlY alloy, a NiCoCrAlY alloy representing industrially used overlay compositions, and a model {beta}NiAl+Hf alloy were tested in 1h thermal cycles at 950 C with different salt coatings deposited onto the surfaces. Whereas the NiCoCrAlY alloy exhibited reasonable resistance against pure sodium sulfate deposits, the NiCrAiY alloy and Rene N5 were attacked severely. Although considered to be an ideal alumina former in air and oxygen at higher temperatures, {beta}NiAl+Hf also suffered from rapid corrosion attack at 950 C when coated with sodium sulfate. The higher level of potassium present in biomass fuels compared with conventional fuels was addressed by testing a NiCoCrAlY alloy coated with salts of different K/Na atomic ratios. Starting at zero Na, the corrosion rate increased considerably when sodium was added to potassium sulfate. In an intermediate region the corrosion rate was initially insensitive to the K/Na ratio but accelerated when very Na-rich compositions were deposited. The key driver for corrosion of the NiCoCrAlY alloy was sodium sulfate rather than potassium sulfate, and no simple additive or synergistic effect of combining sodium and potassium was found.

  13. A novel silver-coated solid-phase microextraction metal fiber based on electroless plating technique.

    PubMed

    Feng, Juanjuan; Sun, Min; Li, Jubai; Liu, Xia; Jiang, Shengxiang

    2011-09-09

    A novel silver-coated solid-phase microextraction fiber was prepared based on electroless plating technique. Good extraction performance of the fiber for model compounds including phthalate esters (dibutyl phthalate, dioctyl phthalate, dicyclohexyl phthalate and diallyl phthalate) and polycyclic aromatic hydrocarbons (naphthalene, fluorene, phenanthrene, fluoranthene) in aqueous solution was obtained. Under the optimized conditions (extraction temperature, extraction time, ionic strength and desorption temperature), the proposed SPME-GC method showed wide linear ranges with correlation coefficients (R(2)) ranging from 0.9745 to 0.9984. The limits of detection were at the range of 0.02 to 0.1 μg L(-1). Single fiber repeatability and fiber-to-fiber reproducibility as well as stability to acid, alkali and high temperature were studied and the results were all satisfactory. The method was applied successfully to the aqueous extracts of disposable paper cup and instant noodle barrel. Several kinds of analytes were detected and quantified.

  14. FBG sensor array-based-low speed impact localization system on composite plate

    NASA Astrophysics Data System (ADS)

    Sai, Yaozhang; Jiang, Mingshun; Sui, Qingmei; Lu, Shizeng; Jia, Lei

    2016-03-01

    A fiber Bragg grating (FBG) sensors-based impact localization system on composite structure and a novel localization algorithm independent of wave velocity were proposed. Six FBG sensors constitute two isosceles right triangle FBG arrays. Impact signals were detected by a high-speed FBG interrogation system. Morlet wavelet transform was employed to extract time differences of impact signals. The straight lines equations, which are through impact source and FBG sensors of right-angled vertices of FBG arrays, can be obtained by the time differences. The coordinate of impact source is the intersection of straight lines. Testing experiments were carried out on composite plate within 400 mm × 400 mm monitor area. The experimental results showed that the maximum and average errors were 20.92 and 8.67 mm, respectively. This article provides a simple and stable impact source localization system independent of wave velocity.

  15. Ultra lightweight PMMA-based composite plates with robust super-hydrophobic surfaces.

    PubMed

    Pareo, Paola; De Gregorio, Gian Luca; Manca, Michele; Pianesi, Maria Savina; De Marco, Luisa; Cavallaro, Francesco; Mari, Margherita; Pappadà, Silvio; Ciccarella, Giuseppe; Gigli, Giuseppe

    2011-11-15

    Extremely lightweight plates made of an engineered PMMA-based composite material loaded with hollow glass micro-sized spheres, nano-sized silica particles and aluminum hydroxide prismatic micro-flakes were realized by cast molding. Their interesting bulk mechanical properties were combined to properly tailored surface topography compatible with the achievement of a superhydrophobic behavior after the deposition of a specifically designed hydrophobic coating. With this aim, we synthesized two different species of fluoromethacrylic polymers functionalized with methoxysilane anchoring groups to be covalently grafted onto the surface protruding inorganic fillers. By modulating the feed composition of the reacting monomers, it was possible to combine the hydrophobic character of the polymer with an high adhesion strength to the substrate and hence to maximize both the water contact angle (up to 157°) and the durability of the easy-to-clean effect (up to 2000 h long outdoor exposure).

  16. Evaluation of Ground Bearing Capacity Estimation Methods Based On Plate Loading Tests

    NASA Astrophysics Data System (ADS)

    Gül, Yavuz; Ceylanoğlu, Atilla

    2016-10-01

    Within the scope of this study, bearing capacities were calculated based on eleven different estimation methods in literature, using some mass and material properties for different rock units (magnetite, syenite, serpentinite, limestone, clayey limestone and gypsum) encountered in three different open-pit mines (Sivas-Ulaş Open-Pit Celestite Mine, Divriği Open-Pit Iron Mine and Kangal Open-Pit Coal Mine) around Sivas in Turkey. Through regression analyses between estimated bearing capacity values and those that had been determined as a result of plate loading tests, bearing capacity estimation methods specified in the literature were assessed. Moreover, four different equations to be used in bearing capacity estimation were proposed.

  17. Exergy efficiency analysis of a flat plate solar collector using graphene based nanofluid

    NASA Astrophysics Data System (ADS)

    Said, Z.; Alim, M. A.; Janajreh, Isam

    2015-10-01

    The thermal efficiency of a flat plate solar thermal collector is largely affected by the thermal conductivity of the fluid used. In this paper, we theoretically analyzed the heat transfer performance, the entropy generation rate, and the exergy efficiency of the two different graphene based nanofluids (graphene/Acetone and graphene/water). From the analyses, it is revealed that by inserting a small amount of graphene nanoparticles in water, exergy efficiency could be enhanced by 21%, comparing to conventional fluids and entropy generation is decreased by 4%. However, the graphene/water nanofluid shows a lower entropy generation. This characteristic suggests that graphene/water nanofluid is a better candidate for flat solar thermal application.

  18. Novel type of neutron image plates based on KCl:Eu2+-LiF

    NASA Astrophysics Data System (ADS)

    Schlapp, M.; Hoelzel, M.; Gilles, R.; Ioffe, A.; Brueckel, T.; Fuess, H.; Seggern, H. Von

    2004-07-01

    Neutron image plates (NIP) provide a mean for the two-dimensional, position-sensitive detection of neutrons. They combine the advantages of a large dynamic range (up to 5 orders of magnitude), good spatial resolution (<=300μm) and large detection areas. NIPs are used at various instruments for powder or single-crystal diffraction in numerous radiation facilities. They have also found an application in neutron radiography and can be used for small-angle neutron scattering (SANS) such as at the Structure Powder DIffractometer (SPODI) at the FRM-II. In this study, the resolution of a novel type of ceramic NIPs based on KCl:Eu2+-LiF is presented and simulations on the applicability of NIPs for neutron detection at the SANS apparatus of SPODI are reported.

  19. A model of convergent plate margins based on the recent tectonics of Shikoku, Japan

    NASA Technical Reports Server (NTRS)

    Bischke, R. E.

    1974-01-01

    A viscoelastic finite element plate tectonic model is applied to displacement data for the island of Shikoku, Japan. The flow properties and geometry of the upper portions of the earth are assumed known from geophysical evidence, and the loading characteristics are determined from the model. The nature of the forces acting on the Philippine Sea plate, particularly in the vicinity of the Nankai trough, is determined. Seismic displacement data related to the 1946 Nankaido earthquake are modeled in terms of a thick elastic plate overlying a fluidlike substratum. The sequence of preseismic and seismic displacements can be explained in terms of two independent processes operating on elastic lithospheric plates: a strain accumulation process caused by vertical downward forces acting on or within the lithosphere in the vicinity of the trench, and a strain release process caused by plate failure along a preexisting zone on weakness. This is a restatement of Reid's elastic rebound theory in terms of elastic lithospheric plates.

  20. A 1.5 THz hot-electron bolometer mixer operated by a planar diode based local oscillator

    NASA Technical Reports Server (NTRS)

    Tong, C. Y. E.; Meledin, D.; Blundell, R.; Erickson, N.; Mehdi, I.; Goltsman, G.

    2003-01-01

    We have developed a 1.5 THz superconducting NbN Hot-Electron Bolometer mixer. It is oprated by an all-solid-state Local Oscillator comprising of a cascade of 4 planar doublers following an MMIC based W-band power amplifier.

  1. Hot corrosion studies of four nickel-base superalloys: B-1900, NASA-TRW VIA, 713C and IN738

    NASA Technical Reports Server (NTRS)

    Fryburg, G. C.; Kohl, F. J.; Stearns, C. A.

    1976-01-01

    The susceptibility to hot corrosion of four nickel base superalloys has been studied at 900 deg and 1000 deg C in one atmosphere of slowly flowing oxygen. Hot corrosion was induced by coating the samples with known doses of NaSO4 and oxidizing the coated samples isothermally on a sensitive microbalance. In general, the order of susceptibility found was: B-1900 is greater than 713C is greater than NASA-TRW VIA and is greater than IN738. This order corresponds to the order of decreasing molybdenum content of the alloys. Chemical evidence for B-1900 indicates that hot corrosion is instigated by acid fluxing of the protective Al2O3 coating by MoO3.

  2. Well Plate-Based Perfusion Culture Device for Tissue and Tumor Microenvironment Replication

    PubMed Central

    Zhang, W.; Gu, Y.; Hao, Y.; Sun, Q.; Konior, K.; Wang, H.

    2015-01-01

    There are significant challenges in developing in vitro human tissue and tumor models that can be used to support new drug development and evaluate personalized therapeutics. The challenges include: (1) working with primary cells which are often difficult to maintain ex vivo, (2) mimicking native microenvironments from which primary cells are harvested, and (3) lack of culture devices that can support these microenvironments to evaluate drug responses in a high-throughput manner. Here we report a versatile well plate-based perfusion culture device that was designed, fabricated and used to: (1) ascertain the role of perfusion in facilitating the expansion of human multiple myeloma cells and evaluate drug response of the cells, (2) preserve the physiological phenotype of primary murine osteocytes by reconstructing the 3D cellular network of osteocytes, and (3) circulate primary murine T cells through a layer of primary murine intestine epithelial cells to recapitulate the interaction of the immune cells with the epithelial cells. Through these diverse case studies, we demonstrate the device’s design features to support: (1) the convenient and spatiotemporal placement of cells and biomaterials into the culture wells of the device; (2) the replication of tissues and tumor microenvironments using perfusion, stromal cells, and/or biomaterials; (3) the circulation of non-adherent cells through the culture chambers; and (4) conventional tissue and cell characterization by plate reading, histology, and flow cytometry. Future challenges are identified and discussed from the perspective of manufacturing the device and making its operation for routine and wide use. PMID:26021852

  3. Investigation of the microbial community in the Odisha hot spring cluster based on the cultivation independent approach.

    PubMed

    Singh, Archana; Subudhi, Enketeswara; Sahoo, Rajesh Kumar; Gaur, Mahendra

    2016-03-01

    Deulajhari hot spring is located in the Angul district of Odisha. The significance of this hot spring is the presence of the hot spring cluster adjacent to the cold spring which attracts the attention of microbiologists to understand the role of physio-chemical factors of these springs on bacterial community structure. Next-generation sequencing technology helps us to depict the pioneering microflora of any ecological niche based on metagenomic approach. Our study represents the first Illumina based metagenomic study of Deulajhari hot spring DH1, and DH2 of the cluster with temperature 65 °C to 55 °C respectively establishing a difference of 10 °C. Comprehensive study of microbiota of these two hot springs was done using the metagenomic sequencing of 16S rRNA of V3-V4 region extracting metagenomic DNA from the two hot spring sediments. Sequencing community DNA reported about 28 phyla in spring DH1 of which the majority were Chloroflexi (22.98%), Proteobacteria (15.51%), Acidobacteria (14.51%), Chlorobi (9.52%), Nitrospirae (8.54%), and Armatimonadetes (7.07%), at the existing physiochemical conditions like; temperature 65 °C, pH 8.06, electro conductivity 0.020 dSm(- 1), and total organic carbon (TOC) 3.76%. About 40 phyla were detected in cluster DH2 at the existing physiochemical parameters like temperature 55 °C, pH 8.10, electro conductivity 0.019 dSm(- 1), and total organic carbon (TOC) 0.58% predominated with Chloroflexi (41.98%), Proteobacteria (10.74%), Nitrospirae (10.01%), Chlorobi (8.73%), Acidobacteria (6.73%) and Planctomycetes (3.73%). Approximately 68 class, 107 order, 171 genus and 184 species were reported in cluster DH1 but 102 class, 180 order, 375 genus and 411 species in cluster DH2. The comparative metagenomics study of the Deulajhari hot spring clusters DH1, and DH2 depicts the differential profile of the microbiota. Metagenome sequences of these two hot spring clusters are deposited to the SRA database and are available in

  4. Error Propagation dynamics of PIV-based pressure calculation 2: from Poisson equations to Kirchhoff plates

    NASA Astrophysics Data System (ADS)

    Pan, Zhao; Whitehead, Jared; Truscott, Tadd

    2016-11-01

    Little research has been done to investigate the dynamics of error propagation from PIV-based velocity measurements to the pressure calculation. Rather than measure experimental error, we analytically investigate error propagation by examining the properties of the Poisson equation directly. Our results provide two contributions to the PIV community. First, we quantify the error bound in the pressure field by illustrating the mathematical roots of why and how PIV-based pressure calculations propagate. Second, we design the "worst case error" for a pressure Poisson solver. In other words, we provide a systematic example where the relatively small errors in the experimental data can lead to maximum error in the corresponding pressure calculations. The 2D calculation of the worst case error surprisingly leads to the classic Kirchhoff plates problem, and connects the PIV-based pressure calculation, which is a typical fluid problem, to elastic dynamics. The results can be used for optimizing experimental error minimization by avoiding worst case scenarios. More importantly, they can be used to design synthetic velocity error for future PIV-pressure challenges, which can be the hardest test case in the examinations.

  5. Hot corrosion of Ni-base turbine alloys in atmospheres in coal-conversion systems

    NASA Technical Reports Server (NTRS)

    Huang, T.; Gulbransen, E. A.; Meier, G. H.

    1979-01-01

    Alkali-metal contaminants in coal may form low-melting sulfate salts during coal gasification or subsequent combustion which can have very deleterious effects on turbine components. The mechanisms for the hot-corrosion phenomena are not completely understood.

  6. A Study on the Recrystallization Behavior of Ni-Based Alloy G3 During Hot Deformation

    NASA Astrophysics Data System (ADS)

    Jiang, He; Dong, Jianxin; Zhang, Maicang; Yao, Zhihao; Jue, Wang

    2016-12-01

    An integrated microstructure evolution model of thermomechanical processing was developed in terms of dynamic recrystallization (DRX), post-dynamic recrystallization (PDRX) and grain growth. Hot compression tests were carried out on a Gleeble-1500 thermal simulator under different conditions to model DRX, PDRX and short-time grain growth during the post-deformation and cooling process. Furthermore, in combination with the established microstructure evolution models, an elastic-plastic finite element model was built using DEFORM-2D software to simulate the microstructure evolution during the hot extrusion process. The simulation result was compared with the microstructure of a hot-extruded pipe of alloy G3 manufactured in a factory. The simulation results agree well with the experimental ones, validating the accuracy of the established microstructure evolution model. Furthermore, the finite element simulation is an effective method for hot deformation analysis, which can provide theoretical guidance for the optimization manufacturing parameters.

  7. Glued Joint Behavior of Ribs for Wood-Based Composite Plates

    NASA Astrophysics Data System (ADS)

    Frolovs, G.; Rocens, K.; Sliseris, J.

    2015-11-01

    This article presents experimental investigations of composite sandwich plywood plates with cell type core and their connections between skin layers of birch plywood and a core of straight and curved plywood honeycomb-type ribs. This shape of core ribs provides several improvements for these plates in the manufacturing process as well as improves the mechanical properties of plywood plates. This specific form of ribs allows simplifying the manufacturing of these plates although it should be detailed and improved. The most typical cases (series of specimens) were compared to the results obtained from FEM (ANSYS) simulations. All thicknesses of elements are chosen according to plywood supplier assortment. Standard birch plywood (Riga Ply) plates were used - three layer plywood was chosen for skin elements (Surfaces) and three or five layer plywood was chosen for edge elements. Different bond pressures were taken to compare their influence on joint strength and stiffness.

  8. Ground-based Observational Characterization of Transiting Hot-Jupiter Atmosphere

    NASA Astrophysics Data System (ADS)

    Chen, G.

    2016-09-01

    Transiting exoplanets are currently among the most favorable targets for atmospheric studies of exoplanets. Such special orbital geometry enables transits and secondary eclipses to be observable, which refer to the events when planets move in front of or behind host stars. Corresponding observations would result in transmission spectroscopy or emission spectroscopy, which are extremely powerful in the investigation of atmospheric compositions and temperature structures. Based on these two techniques, this thesis presents photometric observations on the secondary eclipses of three hot Jupiters using GROND (Gamma-Ray Burst Optical and Near-infrared Detector) mounted on the MPG 2.2 m telescope, and spectroscopic observations on the transits of another two hot Jupiters using DBSP (Double Spectrograph), TSpec (Triple Spectrograph), and COSMIC (Carnegie Observatories Spectroscopic Multislit and Imaging Camera) mounted on the Palomar 5.1 Hale telescope. The primary goal is to search for any detectable signals of atmospheric origin, and to study potential atmospheric diversity among hot Jupiters with various physical properties. The photometric observations on the secondary eclipses of WASP-5 b, WASP-46 b, and WASP-43 b are detailed in Chapter 3, 4, and 5, respectively. The dips of secondary eclipse have been significantly detected for all three hot Jupiters in the K band, along with some possible detection or 3σ upper limit in the J or H band. These near-infrared eclipse detection measures the thermal emission from the deep dayside atmosphere. It is the first time to detect any thermal emission in the near infrared for WASP-5 b and WASP-46 b. Our GROND measurements indicate a roughly isothermal temperature profile of around 2700 K in the deep layers of WASP-5 b's dayside atmosphere. Together with Spitzer observations, which probe higher layers with a temperature of around 1900 K, a temperature inversion is ruled out in the probed pressure range. While an oxygen

  9. Thermal conductivity calibration for hot wire based dc scanning thermal microscopy

    NASA Astrophysics Data System (ADS)

    Lefèvre, Stéphane; Volz, Sebastian; Saulnier, Jean-Bernard; Fuentes, Catherine; Trannoy, Nathalie

    2003-04-01

    Thermal conductivity characterization with nanoscale spatial resolution can be performed by contact probe techniques only. The technique based on a hot anemometer wire probe mounted in an atomic force microscope is now a standard setup. However, no rigorous calibration procedure is provided so far in basic dc mode. While in contact with the sample surface, the electrical current I injected into the probe is controlled so that electrical resistance or the wire temperature is maintained by the Joule effect. The variation in current is assumed to be linearly related to the heat flux lost towards the sample and traditional calibration is carried out by relating the thermal conductivity of a set of samples to the measured current I. We provide analytical and numerical thermal modeling of the tip and sample to estimate the key heat transfer in a conductivity calibration procedure. A simple calibration expression is established that provides thermal conductivity as a function of the probe current or voltage measured. Finally, experimental data allow us to determine the unknown quantities of the parametric form obtained, i.e., the mean tip-sample contact radius and conductance.

  10. Studies on the hot corrosion of a nickel-base superalloy, Udimet 700

    NASA Technical Reports Server (NTRS)

    Misra, A. K.

    1984-01-01

    The hot corrosion of a nickel-base superalloy, Udimet 700, was studied in the temperature range of 884 to 965 C and with different amounts of Na2SO4. Two different modes of degradation were identified: (1) formation of Na2MoO4 - MoO3 melt and fluxing by this melt, and (2) formation of large interconnected sulfides. The dissolution of Cr2O3, TiO2 in the Na2SO4 melt does not play a significant role in the overall corrosion process. The conditions for the formation of massive interconnected sulfides were identified and a mechanism of degradation due to sulfide formation is described. The formation of Ns2MoO4 - MoO3 melt requires an induction period and various physiochemical processes during the induction period were identified. The factors affecting the length of the induction period were also examined. The melt penetration through the oxide appears to be the prime mode of degradation whether the degradation is due to the formation of sulfides or the formation of the Na2MoO4 - MoO3 melt.

  11. Resonant plasmonic terahertz detection in vertical graphene-base hot-electron transistors

    SciTech Connect

    Ryzhii, V.; Otsuji, T.; Ryzhii, M.; Mitin, V.; Shur, M. S.

    2015-11-28

    We analyze dynamic properties of vertical graphene-base hot-electron transistors (GB-HETs) and consider their operation as detectors of terahertz (THz) radiation using the developed device model. The GB-HET model accounts for the tunneling electron injection from the emitter, electron propagation across the barrier layers with the partial capture into the GB, and the self-consistent oscillations of the electric potential and the hole density in the GB (plasma oscillations), as well as the quantum capacitance and the electron transit-time effects. Using the proposed device model, we calculate the responsivity of GB-HETs operating as THz detectors as a function of the signal frequency, applied bias voltages, and the structural parameters. The inclusion of the plasmonic effect leads to the possibility of the GB-HET operation at the frequencies significantly exceeding those limited by the characteristic RC-time. It is found that the responsivity of GB-HETs with a sufficiently perfect GB exhibits sharp resonant maxima in the THz range of frequencies associated with the excitation of plasma oscillations. The positions of these maxima are controlled by the applied bias voltages. The GB-HETs can compete with and even surpass other plasmonic THz detectors.

  12. Development of a Calicum-Based Sorbent for Hot Gas Cleanup.

    SciTech Connect

    Wheelock, T.W.; Constant, K.; Doraiswamy, L.K.; Akiti, T.; Zhu, J.; Amanda, A.; Roe, R.

    1997-09-01

    Further review of the technical literature has provided additional information which will support the development of a superior calcium-based sorbent for hot gas cleanup in IGCC systems. Two general methods of sorbent preparation are being investigated. One method involves impregnating a porous refractory substrate with calcium while another method involves pelletizing lime or other calcium containing materials with a suitable binder. Several potential substrates, which are made of alumina and are commercially available, have been characterized by various methods. The surface area and apparent density of the materials have been measured, and it has been shown that some of the high surface area materials (i.e., 200-400 m{sub 2}/g) undergo a large decrease in surface area when heated to higher temperatures. Some of the lower surface area materials (i.e., 1-30 m{sub 2}/g) have been successfully impregnated with calcium by soaking them in a calcium nitrate solution and then heat treating them to decompose the nitrate. Potentially useful sorbents have also been prepared by pelletizing type I Portland cement and mixtures of cement and lime.

  13. High cycle fatigue and fracture behaviour of a hot isostatically pressed nickel-based superalloy

    NASA Astrophysics Data System (ADS)

    Qiu, Chunlei; Wu, Xinhua

    2014-01-01

    Powder of a nickel-based superalloy, RR1000, has been hot isostatically pressed (HIPped) at a supersolvus temperature and post-HIP heat treated to produce different microstructures. Microstructures were investigated using a scanning electron microscope together with an energy dispersive X-ray spectrometer and a wave-length dispersive X-ray spectrometer. High cycle four-point bending fatigue and tension-tension fatigue tests have been performed on the fabricated samples. It was found that HIPped and aged samples showed the best four-point bending fatigue limit while HIPped and solution-treated and aged samples had the lowest fatigue limit. The four-point bending fatigue crack initiations all occurred from the sample surfaces either at the sites of inclusion clusters or by cleavage through large grains on the surfaces. The tension-tension fatigue crack initiation occurred mainly due to large hafnia inclusion clusters, with lower fatigue lives for samples where inclusions were closer to the surface. Crack initiation at the compact Al2O3 inclusion cluster led to a much higher fatigue life than found when cracks were initiated by large hafnia inclusion clusters. The tension-tension fatigue limits were shown to decrease with increased testing temperature (from room temperature to 700 °C).

  14. SHARK: Flight Results of an UHTC-Based Nose Related to USV Hot Structures

    NASA Astrophysics Data System (ADS)

    Gardi, R.; Del Vecchio, A.; Russo, G.; Marino, G.

    2011-05-01

    In the frame of USV program, CIRA is developing different projects aimed to develop new technologies for the future hypersonic vehicles. One of these technological projects is Sharp Hot Structures (SHS) and it is aimed to the realization of innovative thermo- structures, based on innovative material solution, able to sustain the heat loads generated during the hypersonic flight. Because the slender configuration of the USV program vehicles, SHS is focused on sharp geometries, like sharp leading edges and sharp nose cones. CIRA, for many years, is investigating the effectiveness of ultra high temperature ceramic materials (UHTC) by means of numerical simulations, ground testing in plasma torch and in SCIROCCO, the 70MW plasma wind tunnel (PWT) facility at CIRA. More recently CIRA is moving the experimentation in real flight environment, boarding UHTC components on the re-entering space capsules EXPERT and SHARK. The former is a European experimental test bed boarding a couple of UHTC fins, already qualified and integrated on the vehicle. SHARK is a 20kg capsule launched on March the 26th 2010 from Kiruna with the European sounding rocker Maxus-8. During the ascent parabola, the capsule was released and successfully executed its 15 minutes ballistic flight and then re-entered in the atmosphere from a 700km altitude. The capsule has been recovered on July the 1st and all data have been acquired. All the instrumentation worked nicely and the data acquisition continued even after the landing, confirming the robustness of the design.

  15. Hot coal gas desulfurization with manganese based sorbents. Quarterly report, June--September 1994

    SciTech Connect

    Hepworth, M.T.; Slimane, R.B.

    1994-11-01

    The focus of work being performed on hot coal gas desulfurization at the Morgantown Energy Technology Center is primarily in the use of zinc titanate sorbents; however, prior studies indicated that an alternate sorbent, manganese dioxide-containing ore in mixture with alumina (75 wt% ore + 25 wt% Al{sub 2}O{sub 3}) appears to be a strong contender to zinc-based sorbents. Manganese, for example, has a lower vapor pressure in the elemental state than zinc; hence, it is not as likely to undergo zinc-depletion from the sorbent surface upon loading and regeneration cycles. Also manganese oxide is less readily reduced to the elemental state than iron; hence, the range of reduction potentials for oxygen is somewhat greater than for zinc ferrite. In addition, thermodynamic analysis of the manganese-oxygen-sulfur system shows it to be less amenable to sulfation than zinc ferrite. Also manganese chlorides are much less stable and volatile than zinc chlorides. Potential also exists for utilization of manganese at higher temperatures than zinc ferrite or zinc titanate. This Eighth Quarterly Report documents progress in pelletizing and testing via thermo-gravimetric analysis of individual pellet formulations of manganese ore/alumina combinations and also manganese carbonate/alumina with two binders, dextrin and bentonite.

  16. Plate motion

    SciTech Connect

    Gordon, R.G. )

    1991-01-01

    The motion of tectonic plates on the earth is characterized in a critical review of U.S. research from the period 1987-1990. Topics addressed include the NUVEL-1 global model of current plate motions, diffuse plate boundaries and the oceanic lithosphere, the relation between plate motions and distributed deformations, accelerations and the steadiness of plate motions, the distribution of current Pacific-North America motion across western North America and its margin, plate reconstructions and their uncertainties, hotspots, and plate dynamics. A comprehensive bibliography is provided. 126 refs.

  17. Investigation of the differences between the "Cold" and "Hot" nature of Coptis chinensis Franch and its processed materials based on animal's temperature tropism.

    PubMed

    Zhou, CanPing; Wang, JiaBo; Zhang, XueRu; Zhao, YanLing; Xia, XinHua; Zhao, HaiPing; Ren, YongShen; Xiao, XiaoHe

    2009-11-01

    The description and differentiation of the so-called "Cold" and "Hot" natures, the primary "Drug Naure" of Chinese medicine, is the focus of theoretical research. In this study, the divergency between the "Cold" and the "Hot" natures was investigated through examining the temperature tropism of mice affected by Coptis chinensis Franch and its processed materials by using a cold/hot plate differentiating technology. After exposure to C. chinensis Franch, the macroscopic behavioral index of the remaining rate (RR) on a warm pad (40 degrees C) significantly increased (P<0.05), suggesting the enhancement of Hot tropism. The internal indexes of adenosine triphosphatase (ATPase) activity and oxygen consuming volume decreased significantly (P<0.05), suggesting the decapability of energy metabolism. This external behavior of Hot tropism might reflect the internal Cold nature of C. chinensis Franch. However, the processed materials of C. chinensis Franch exhibited a different Cold nature in temperature tropism compared with crude C. chinensis Franch (CC): the Cold nature of bile-processed C. chinensis Franch (BC) enhanced while the ginger-processed C. chinensis Franch (GC) changed inversely. The changing sequence was consistent with the theoretical prognostication. It is indicated that the external Cold & Hot natures of Chinese medicine may possibly reflect in an ethological way for the changes of animal's temperature tropism which might be internally regulated by the body's energy metabolism.

  18. Hot Flashes

    MedlinePlus

    Diseases and Conditions Hot flashes By Mayo Clinic Staff Hot flashes are sudden feelings of warmth, which are usually most intense over the ... skin may redden, as if you're blushing. Hot flashes can also cause profuse sweating and may ...

  19. Hot microswimmers

    NASA Astrophysics Data System (ADS)

    Kroy, Klaus; Chakraborty, Dipanjan; Cichos, Frank

    2016-11-01

    Hot microswimmers are self-propelled Brownian particles that exploit local heating for their directed self-thermophoretic motion. We provide a pedagogical overview of the key physical mechanisms underlying this promising new technology. It covers the hydrodynamics of swimming, thermophoresis and -osmosis, hot Brownian motion, force-free steering, and dedicated experimental and simulation tools to analyze hot Brownian swimmers.

  20. Development and testing of a hot-air solar collector

    NASA Technical Reports Server (NTRS)

    Caudle, J. M.

    1979-01-01

    Summarized report on development and testing of hot-air flat-plate solar collector includes structural details, coating selection, and spacing between coating and glass plate. Report gives complete performance specifications and extensive certifications test report.

  1. Ultrathin Terahertz Quarter-wave plate based on Split Ring Resonator and Wire Grating hybrid Metasurface

    PubMed Central

    Nouman, Muhammad Tayyab; Hwang, Ji Hyun; Jang, Jae-Hyung

    2016-01-01

    Planar metasurface based quarter-wave plates offer various advantages over conventional waveplates in terms of compactness, flexibility and simple fabrication; however they offer very narrow bandwidth of operation. Here, we demonstrate a planar terahertz (THz) metasurface capable of linear to circular polarization conversion and vice versa in a wide frequency range. The proposed metasurface is based on horizontally connected split ring resonators and is realized on an ultrathin (0.05λ) zeonor substrate. The fabricated quarter waveplate realizes linear to circular polarization conversion in two broad frequency bands comprising 0.64–0.82 THz and 0.96–1.3 THz with an insertion loss ranging from −3.9 to −10 dB. By virtue of ultrathin sub wavelength thickness, the proposed waveplate design is well suited for application in near field THz optical systems. Additionally, the proposed metasurface design offers novel transmission phase characteristics that present further opportunities to realize dynamic polarization control of incident waves. PMID:27958358

  2. Saturation and Dynamic Range of Microchannel Plate-Based X-Ray Imagers

    SciTech Connect

    ,

    2012-05-04

    This paper describes recent advances in Monte Carlo simulations of microchannel plate (MCP)–based x-ray detectors, a continuation of ongoing work in this area. A Monte Carlo simulation model has been developed over the past several years by National Security Technologies, LLC (NSTec). The model simulates the secondary electron emission process in an MCP pore and includes the effects of gain saturation. In this work we focus on MCP gain saturation and dynamic range. We have performed modeling and experimental characterizations of L/D = 46, 10-micron diameter, MCP-based detectors. The detectors are typically operated by applying a subnanosecond voltage pulse, which gates the detector on. Agreement between the simulations and experiment is very good for a variety of voltage pulse waveforms ranging in width from 150 to 300 ps. The results indicate that such an MCP begins to show nonlinear gain around 5 × 10^4 electrons per pore and hard saturation around 105 electrons per pore. The simulations show a difference in MCP sensitivity vs voltage for high flux of photons producing large numbers of photoelectrons on a subpicosecond timescale. Simulations and experiments both indicate an MCP dynamic range of 1 to 10,000, and the dynamic range depends on how the voltage is applied.

  3. Ultrathin Terahertz Quarter-wave plate based on Split Ring Resonator and Wire Grating hybrid Metasurface

    NASA Astrophysics Data System (ADS)

    Nouman, Muhammad Tayyab; Hwang, Ji Hyun; Jang, Jae-Hyung

    2016-12-01

    Planar metasurface based quarter-wave plates offer various advantages over conventional waveplates in terms of compactness, flexibility and simple fabrication; however they offer very narrow bandwidth of operation. Here, we demonstrate a planar terahertz (THz) metasurface capable of linear to circular polarization conversion and vice versa in a wide frequency range. The proposed metasurface is based on horizontally connected split ring resonators and is realized on an ultrathin (0.05λ) zeonor substrate. The fabricated quarter waveplate realizes linear to circular polarization conversion in two broad frequency bands comprising 0.64–0.82 THz and 0.96–1.3 THz with an insertion loss ranging from ‑3.9 to ‑10 dB. By virtue of ultrathin sub wavelength thickness, the proposed waveplate design is well suited for application in near field THz optical systems. Additionally, the proposed metasurface design offers novel transmission phase characteristics that present further opportunities to realize dynamic polarization control of incident waves.

  4. A Cell-based PDE4 Assay in 1536-well Plate format for High Throughput Screening

    PubMed Central

    Titus, Steven A.; Li, Xiao; Southall, Noel; Lu, Jianming; Inglese, James; Brasch, Michael; Austin, Christopher P.; Zheng, Wei

    2009-01-01

    The cyclic nucleotide phosphodiesterases (PDEs) are intracellular enzymes that catalyze the hydrolysis of 3', 5'-cyclic nucleotides, such as cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP), to their corresponding 5'-nucleotide monophosphates. These enzymes play an important role in controlling cellular concentrations of cyclic nucleotides and thus regulate a variety of cellular signaling events. PDEs are emerging as drug targets for several diseases including asthma, cardiovascular disease, ADHD, Parkinson’s disease, and Alzheimer’s disease. Though biochemical assays with purified recombinant PDE enzymes and cAMP or cGMP substrate are commonly used for compound screening, cell-based assays would provide a better assessment of compound activity in a more physiological context. Here we report the development and validation of a new cell-based PDE4 assay using a constitutively active GPCR as a driving force for cAMP production and a cyclic nucleotide gated (CNG) cation channel as a biosensor in 1536-well plates. PMID:18591513

  5. Numerical determination of statistical energy analysis parameters of directly coupled composite plates using a modal-based approach

    NASA Astrophysics Data System (ADS)

    Seçgin, Abdullah

    2013-01-01

    Statistical energy analysis (SEA) parameters such as average modal spacing, coupling loss factor and input power are numerically determined for point connected, directly coupled symmetrically laminated composite plates using a modal-based approach. The approach is an enhancement of classical wave transmission formula. Unlike most of the existing numerical or experimental techniques, the approach uses uncoupled plate modal information and treats substructure by means of averaged modal impedances. The procedure introduced here is verified using analytical definitions of infinite orthotropic plates which physically resemble to laminated plates for (under) specific conditions, and is tested by performing experimental power injection method (PIM) for an actual, right-angled composite structure. In the development process, force and moment transmissions are individually considered in order to be consistent with analytical formulations. Modal information of composite plates is statistically evaluated by the discrete singular convolution method with random boundary conditions. Proposed methodology not only provides an efficient use of SEA method in high frequency vibration analysis of composite structures, but also enhances SEA accuracy in mid frequency region in which conventional SEA fails. Furthermore, the effect of orientation angles of laminations on SEA parameters are also discussed in mid and high frequency regions.

  6. Plate-based diversity subset screening generation 2: an improved paradigm for high-throughput screening of large compound files.

    PubMed

    Bell, Andrew S; Bradley, Joseph; Everett, Jeremy R; Loesel, Jens; McLoughlin, David; Mills, James; Peakman, Marie-Claire; Sharp, Robert E; Williams, Christine; Zhu, Hongyao

    2016-11-01

    High-throughput screening (HTS) is an effective method for lead and probe discovery that is widely used in industry and academia to identify novel chemical matter and to initiate the drug discovery process. However, HTS can be time consuming and costly and the use of subsets as an efficient alternative to screening entire compound collections has been investigated. Subsets may be selected on the basis of chemical diversity, molecular properties, biological activity diversity or biological target focus. Previously, we described a novel form of subset screening: plate-based diversity subset (PBDS) screening, in which the screening subset is constructed by plate selection (rather than individual compound cherry-picking), using algorithms that select for compound quality and chemical diversity on a plate basis. In this paper, we describe a second-generation approach to the construction of an updated subset: PBDS2, using both plate and individual compound selection, that has an improved coverage of the chemical space of the screening file, whilst only selecting the same number of plates for screening. We describe the validation of PBDS2 and its successful use in hit and lead discovery. PBDS2 screening became the default mode of singleton (one compound per well) HTS for lead discovery in Pfizer.

  7. 96-Well Polycarbonate-Based Microfluidic Titer Plate for High-Throughput Purification of DNA and RNA

    PubMed Central

    Witek, Małgorzata A.; Hupert, Mateusz L.; Park, Daniel S.-W.; Fears, Kirby; Murphy, Michael C.; Soper, Steven A.

    2008-01-01

    We report a simple and effective method for the high-throughput purification of a variety of nucleic acids (NAs) from whole cell lysates or whole blood using a photactivated polycarbonate solid-phase reversible immobilization (PPC-SPRI) microfluidic chip. High-throughput operation was achieved by placing 96 purification beds, each containing an array of 3800 20 µm diameter posts, on a single 3″ × 5″ polycarbonate (PC) wafer fabricated by hot embossing. All beds were interconnected through a common microfluidic network that permitted parallel access through the use of a vacuum and syringe pump for delivery of immobilization buffer (IB) and effluent. The PPC-SPRI purification was accomplished by condensation of NAs onto a UV-modified PC surface in the presence of the IB comprised of polyethylene glycol, NaCl, and ethanol with a composition dependent on the length of the NAs to be isolated and the identity of the sample matrix. The performance of the device was validated by quantification of the recovered material following PCR (for DNA) or RT-PCR (for RNA). The extraction bed load capacity of NAs was 206 ± 93 ng for gDNA and 165 ± 81 ng for TRNA from Escherichia coli. Plate-to-plate variability was found to be 35 ± 10%. The purification process was fast (>30 min) and easy to automate, and the low cost of wafer fabrication makes it appropriate for single-use applications. PMID:18355091

  8. Control of supersonic axisymmetric base flows using passive splitter plates and pulsed plasma actuators

    NASA Astrophysics Data System (ADS)

    Reedy, Todd Mitchell

    An experimental investigation evaluating the effects of flow control on the near-wake downstream of a blunt-based axisymmetric body in supersonic flow has been conducted. To better understand and control the physical phenomena that govern these massively separated high-speed flows, this research examined both passive and active flow-control methodologies designed to alter the stability characteristics and structure of the near-wake. The passive control investigation consisted of inserting splitter plates into the recirculation region. The active control technique utilized energy deposition from multiple electric-arc plasma discharges placed around the base. The flow-control authority of both methodologies was evaluated with experimental diagnostics including particle image velocimetry, schlieren photography, surface flow visualization, pressure-sensitive paint, and discrete surface pressure measurements. Using a blowdown-type wind tunnel reconstructed specifically for these studies, baseline axisymmetric experiments without control were conducted for a nominal approach Mach number of 2.5. In addition to traditional base pressure measurements, mean velocity and turbulence quantities were acquired using two-component, planar particle image velocimetry. As a result, substantial insight was gained regarding the time-averaged and instantaneous near-wake flow fields. This dataset will supplement the previous benchmark point-wise laser Doppler velocimetry data of Herrin and Dutton (1994) for comparison with new computational predictive techniques. Next, experiments were conducted to study the effects of passive triangular splitter plates placed in the recirculation region behind a blunt-based axisymmetric body. By dividing the near-wake into 1/2, 1/3, and 1/4 cylindrical regions, the time-averaged base pressure distribution, time-series pressure fluctuations, and presumably the stability characteristics were altered. While the spatial base pressure distribution was

  9. Sustained release from hot-melt extruded matrices based on ethylene vinyl acetate and polyethylene oxide.

    PubMed

    Almeida, A; Brabant, L; Siepmann, F; De Beer, T; Bouquet, W; Van Hoorebeke, L; Siepmann, J; Remon, J P; Vervaet, C

    2012-11-01

    The aim of the present study was to evaluate the importance of matrix flexibility of hot-melt extruded (HME) ethylene vinyl acetate (EVA) matrices (with vinyl acetate (VA) contents of 9%, 15%, 28% and 40%), through the addition of hydrophilic polymers with distinct swelling capacity. Polyethylene oxide (PEO 100K, 1M and 7M) was used as swelling agent and metoprolol tartrate (MPT) as model drug. The processability via HME and drug release profiles of EVA/MPT/PEO formulations were assessed. Solid state characteristics, porosity and polymer miscibility of EVA/PEO matrices were evaluated by means of DSC, X-ray tomography and Raman spectroscopy. The processability via HME varied according to the VA content: EVA 40 and 28 were extruded at 90°C, whereas higher viscosity EVA grades (EVA 15 and 9) required a minimum extrusion temperature of 110°C to obtain high-quality extrudates. Drug release from EVA matrices depended on the VA content, PEO molecular weight and PEO content, matrix porosity as well as pore size distribution. Interestingly, the interplay of PEO leaching, matrix swelling, water influx and changes in matrix porosity influenced drug release: EVA 40- and 28-based matrices extruded with PEO of higher MW accelerated drug release, whereas for EVA 15- and 9-based matrices, drug release slowed down. These differences were related to the distinct polymer flexibility imposed by the VA content (lower VA content presents higher crystallinity and less free movement of the amorphous segments resulting in a higher rigidity). In all cases, diffusional mass transport seems to play a major role, as demonstrated by mathematical modeling using an analytical solution of Fick's second law. The bioavailability of EVA 40 and 28 matrices in dogs was not significantly different, independent of PEO 7M concentration.

  10. Fabrication of an Aluminum Based Hot Electron Mixer for Terahertz Applications

    NASA Technical Reports Server (NTRS)

    Echternach, P. M.; LeDuc, H. G.; Skalare, A.; McGrath, W. R.

    2000-01-01

    Aluminum based diffusion cooled hot electron bolometers (HEB) mixers, predicted to have better noise, bandwidth and to require less LO power than Nb based diffusion cooled HEBs, have been fabricated. Preliminary DC tests were performed. The bolometer elements consisted of short (0.1 to 0.3 micron), narrow (0.08 to 0. 15 micron) and thin (11 nm) aluminum wires connected to large contact pads consisting of a novel trilayer Al/Ti/Au. The patterns were defined by electron beam lithography and the metal deposition involved a double angle process, the Aluminum wires being deposited straight on and the pads being deposited at a 45 degree angle without breaking vacuum. The Al/Ti/Au trilayer was developed to provide a way of making contact between the aluminum wire and the gold antenna. The Titanium layer acts as a diffusion barrier to avoid damage of the Aluminum contact and bolometer wire and to lower the transition temperature of the pads to below that of the bolometer wire. The Au layer avoids the formation of an oxide on the Ti layer and provides good electrical contact to the IF/antenna structure. The resistance of the bolometers as a function of temperature was measured. It is clear that below the transition temperature of the wire (1.8K) but above the transition temperature of the contact pads (0.6K), the proximity effect drives most of the bolometer wire normal, causing a very broad transition. This effect should not affect the performance of the bolometers since they will be operated at a temperature below the TC of the pads. This is evident from the IV characteristics measured at 0.3K. RF characterization tests will begin shortly.

  11. Hot N Sour Mantle Soup on Indian Plate During Cretaceous- Evidence from Clumped Isotope and Geochemical Studies of Sung Valley Carbonatite, India

    NASA Astrophysics Data System (ADS)

    Ghosh, P.; Banerjee, Y.; Tiwari, A.; Srivastava, R. K.

    2015-12-01

    Geological processes involved in the formation of Carbonatite rocks are complex and so is the understanding about its formational temperature. Fluid inclusion studies (1) on Carbonatite and their associated Ijolites showed a homogenization temperature of 1000-1100°C for Ijoltes and a temperature (T) range of 200-600°C was assigned to the carbonatite melts. Liquid immiscibility process is held responsible for the origin of parental carbonated (ijolititic/ nephelinitic) magma. The homogenization T signifies about a time interval during which there must be a considerable amount of T dropdown soon after the formation of Ijolite and subsequent crystallization of the residual carbonatite magma. However the lack of information about the T of the primary carbonated melt remains as an important area of petrological research. Experimental studies suggest a T range of 950-1400°C for the primary carbonate melt (2). Advent of Clumped isotope thermometry (3) allowed independent method for estimation of the formational T and provide avenues to derive composition of CO2 in equilibrium with carbonate melt. Earlier attempt involving carbonatites from several locations (4) captured range of T between 83°-416°C . Here we present our observation on calcite growth T in the carbonatites from the Cretaceous Sung valley ultramafic-alkaline-carbonatite complex. Based on stable C,O isotope study and Sr, Nd isotopic composition a mantle origin- genetically linked with the Kerguelen plume was proposed (5). Clumped isotope study on the same samples revealed consistent C and O isotope compositions, providing Δ47 values ranging from 0.32 to 0.48. δ13C and δ18O (in VPDB) values of the present study falls within the "Primary Igneous Carbonatite Field" (6). Using high T thermometry equation (7) we obtained a T range of 137-474 °C for the calcite present in the samples. The T recorded in our study is lower than that deduced experimental values of 960-625°C at 0.1 GPa (8) and fluid inclusion

  12. [Determination of optical axis of quartz wave plate based on spectroscopic ellipsometer].

    PubMed

    Zhang, Bei-Bei; Han, Pei-Gao; Fu, Shi-Rong; Zhu, Jiu-Kai; Yan, Ke-Zhu

    2013-01-01

    The optical axis is one of the most important parameters in the application of wave plates. In the transmission mode of spectroscopic ellipsometer, taking the advantage of Jones matrix to analyse the phase difference of P and S directions in the process of spinning wave plate, a new method for the determination of optical axis of quartz wave plate was designed. The method has characteristics of simple light path structure and high efficiency in the judging of the optical axis, and this method thus got a good practicability.

  13. Hot-compress: A new postdeposition treatment for ZnO-based flexible dye-sensitized solar cells

    SciTech Connect

    Haque Choudhury, Mohammad Shamimul

    2016-08-15

    Highlights: • A new postdeposition treatment named hot-compress is introduced. • Hot-compression gives homogeneous compact layer ZnO photoanode. • I-V and EIS analysis data confirms the efficacy of this method. • Charge transport resistance was reduced by the application of hot-compression. - Abstract: This article introduces a new postdeposition treatment named hot-compress for flexible zinc oxide–base dye-sensitized solar cells. This postdeposition treatment includes the application of compression pressure at an elevated temperature. The optimum compression pressure of 130 Ma at an optimum compression temperature of 70 °C heating gives better photovoltaic performance compared to the conventional cells. The aptness of this method was confirmed by investigating scanning electron microscopy image, X-ray diffraction, current-voltage and electrochemical impedance spectroscopy analysis of the prepared cells. Proper heating during compression lowers the charge transport resistance, longer the electron lifetime of the device. As a result, the overall power conversion efficiency of the device was improved about 45% compared to the conventional room temperature compressed cell.

  14. KINETICS OF Mn-BASED SORBENTS FOR HOT COAL GAS DESULFURIZATION

    SciTech Connect

    K.A. SADECKI; M.T. HEPWORTH

    1997-06-15

    Manganese-based sorbents have been investigated for the removal of hydrogen sulfide (the primary sulfur bearing compound) from hot coal gases. Four formulations of Mn-based sorbents were tested in an ambient-pressure fixed-bed reactor to determine steady state H2S concentrations, breakthrough times and effectiveness of the sorbent when subjected to cyclic sulfidation and regeneration testing. In previous reports, the sulfidation and regeneration results from cyclic testing done at 550 and 600 °C were presented. Manganese-based sorbents with molar ratios > 1:1 Mn:Substrate were effective in reducing the H2S concentration in simulated coal gases to less than 100 ppmv over five cycles. Actual breakthrough time for formulation C6-2-1100 was as high as 73% of breakthrough time based on wt% Mn in sorbent at 600 °C. Regeneration tests determined that loaded pellets can be essentially completely regenerated in air/steam mixture at 750 °C with minimal sulfate formation. In this report, the performance of the leading formulation (designated C6-2) was investigated for high temperature removal of H2S from simulated coal-derived fuel gas under varying sorbent induration temperature, reaction temperature, and superficial gas velocity. Sulfidation experiments were performed in an ambient pressure fixed-bed reactor between 500 °C and 600 °C. Four tests were conducted with each test consisting of four cycles of sulfidation and regeneration. Results showed that the induration temperature of the sorbent and the reaction temperature greatly affected the H2S removal capacity of the sorbent while the superficial gas velocity between 1090 and 1635 cm/min had minimal affect on the sorbent's breakthrough capacity. Sorbent also showed 30 to 53% loss of its strength over four cycles of sulfidation and regeneration. The former being sorbent indurated at 1115 °C and the prior being sorbent indurated at 1100 °C.

  15. Simple plate-based, parallel synthesis of disulfide fragments using the CuAAC click reaction.

    PubMed

    Turner, David M; Tom, Christopher T M B; Renslo, Adam R

    2014-12-08

    Disulfide exchange screening is a site-directed approach to fragment-based lead discovery that requires a bespoke library of disulfide-containing fragments. Previously, we described a simple one-pot, two-step synthesis of disulfide fragments from amine- or acid-bearing starting materials. Here, we describe the synthesis of disulfide fragments that bear a 1,4-substituted-1,2,3-triazole linkage between disulfide and molecular diversity element. This work establishes the compatibility of copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) chemistry with a one-pot, two-step reaction sequence that can be readily parallelized. We performed 96 reactions in a single deep-well microtiter plate, employing 48 alkynes and two different azide linker reagents. From this effort, a total of 81 triazole-containing disulfide fragments were obtained in useful isolated yields. Thus, CuAAC chemistry offers an experimentally convenient method to rapidly prepare disulfide fragments that are structurally distinct from fragments accessed via amide, sulfonamide, or isocyanate chemistries.

  16. Experimental study of a vortex ring impacting a smart material-based cantilevered plate

    NASA Astrophysics Data System (ADS)

    Peterson, Sean; Porfiri, Maurizio

    2011-11-01

    Recent developments in lightweight smart materials have generated scientific and technological advancements in small scale energy harvesting for powering low-consumption electronic devices. Often, energy is harvested from base excitation of a cantilevered smart material strip. In this case, the encompassing fluid acts as a passive damper, reducing the vibration amplitude and frequency, which reduces the harvesting capacity. By comparison, relatively few research efforts to date have explored the feasibility of using smart materials for harvesting energy directly from fluid motion. In this paper we employ vortex rings as the source from which to extract energy and use an ionic polymer metal composite (IPMC) strip in a cantilevered configuration as the harvesting device. Vortex rings, generated using a piston/cylinder arrangement submersed in water, are fired at the IPMC harvester and the resulting impact is recorded using a high speed video camera. The vortex ring propagation and circulation are estimated using flow visualization and particle image velocimetry. The plate deflection and electrical output are recorded as functions of time and correlated to the vortex strength and geometry.

  17. Flat plate solar collector design and performance. Citations from the Engineering Index data base

    NASA Astrophysics Data System (ADS)

    Hundemann, A. S.

    1980-09-01

    Citations on the design, thermal performance, and optimization of air and liquid type flat plate collectors are covered. Topic areas include heat loss and heat transfer, effect of orientation, corrosion protection, optical coatings, enhancement of performance through the use of planar reflectors, and the effect of honeycomb layers on collector performance. A few studies pertain to grooved, corrugated, or V-trough collectors. Methods of measuring the performance of flat plate collectors and computer optimization studies are included.

  18. GIS-based Reconstruction of Pangaea with Recent Progresses in Plate Tectonics

    NASA Astrophysics Data System (ADS)

    Kwon, O.-H.; Cheong, H.-B.; Lee, Y.-W.

    2012-04-01

    It is now widely accepted that the continents or land masses are constantly, slowly moving, or drifting over the asthenosphere as the sea floors spread in response to the mantle convection. These continents were joined together at one time, some 250 million years ago, in a single giant landmass called Pangaea. Alfred Wegener, who proposed originally the hypothesis of continental drift, succeeded in reconstructing the Pangaea in early 20th century, by gathering evidences such as land features, fossils, and climate change. The shape of Pangaea shown by Wegener is a huge landmass which is in rounded shape close to an oval. The Pangaea of Wegener was found to be in good agreement with the supercontinent which was reconstructed by modern scientists in late 1960s based on concrete and sophisticated sciences such as the plate tectonics. There are a couple of shapes describing the Pangaea by now, other than the Wegener's, that are recognized by the geological community. In spite of profound geological data and development of related-area sciences, uncertainties still remains on the precise shape of Pangaea before the stage of breaking up and drifting apart. In this study, the Pangaea is reconstructed taking the recent progresses of plate tectonics into full consideration with the use of an elaborate Geographical Information System (GIS) mapping technique. For a better visualization of the shape of the supercontinent the equidistant map projection is incorporated to display the Pangaea, where the central point of Pangaea is placed on the center of the map. The Pangaea reconstructed in this way appears in an almost circular shape, which has never been seen in previous studies (Fig. 1). The radius of the circle which circumscribes the Pangaea is about 9 000 km, giving the total area slightly above that of continents and lands of present day, because some of the continental margins were considered as a part of continents. This result suggests us that the Pangaea might have

  19. An Agar-Based Method for Plating Marine Protozoan Parasites of the Genus Perkinsus

    PubMed Central

    Cold, Emma R.; Freyria, Nastasia J.; Martínez Martínez, Joaquín; Fernández Robledo, José A.

    2016-01-01

    The genus Perkinsus includes protozoan parasites of mollusks responsible for losses in the aquaculture industry and hampering the recovery of natural shellfish beds worldwide, and they are a key taxon for understanding intracellular parasitism adaptations. The ability to propagate the parasite in liquid media, in the absence of the host, has been crucial for improving understanding of its biology; however, alternative techniques to grow the parasite are needed to explore other basic aspects of the Perkinsus spp. biology. We optimized a DME: Ham’s F12–5% FBS- containing solid agar medium for plating Perkinsus marinus. This solid medium supported trophozoite propagation both by binary fission and schizogony. Colonies were visible to the naked eye 17 days after plating. We tested the suitability of this method for several applications, including the following: 1) Subcloning P. marinus isolates: single discrete P. marinus colonies were obtained from DME: Ham’s F12–5% FBS– 0.75% agar plates, which could be further propagated in liquid medium; 2) Subcloning engineered Perkinsus mediterraneus MOE[MOE]: GFP by streaking cultures on plates; 3) Chemical susceptibility: Infusing the DME: Ham’s F12–5% FBS– 0.75% agar plates with triclosan resulted in inhibition of the parasite propagation in a dose-dependent manner. Altogether, our plating method has the potential for becoming a key tool for investigating diverse aspects of Perkinsus spp. biology, developing new molecular tools, and for biotechnological applications. PMID:27149378

  20. An Agar-Based Method for Plating Marine Protozoan Parasites of the Genus Perkinsus.

    PubMed

    Cold, Emma R; Freyria, Nastasia J; Martínez Martínez, Joaquín; Fernández Robledo, José A

    2016-01-01

    The genus Perkinsus includes protozoan parasites of mollusks responsible for losses in the aquaculture industry and hampering the recovery of natural shellfish beds worldwide, and they are a key taxon for understanding intracellular parasitism adaptations. The ability to propagate the parasite in liquid media, in the absence of the host, has been crucial for improving understanding of its biology; however, alternative techniques to grow the parasite are needed to explore other basic aspects of the Perkinsus spp. biology. We optimized a DME: Ham's F12-5% FBS- containing solid agar medium for plating Perkinsus marinus. This solid medium supported trophozoite propagation both by binary fission and schizogony. Colonies were visible to the naked eye 17 days after plating. We tested the suitability of this method for several applications, including the following: 1) Subcloning P. marinus isolates: single discrete P. marinus colonies were obtained from DME: Ham's F12-5% FBS- 0.75% agar plates, which could be further propagated in liquid medium; 2) Subcloning engineered Perkinsus mediterraneus MOE[MOE]: GFP by streaking cultures on plates; 3) Chemical susceptibility: Infusing the DME: Ham's F12-5% FBS- 0.75% agar plates with triclosan resulted in inhibition of the parasite propagation in a dose-dependent manner. Altogether, our plating method has the potential for becoming a key tool for investigating diverse aspects of Perkinsus spp. biology, developing new molecular tools, and for biotechnological applications.

  1. Hot coal gas desulfurization with manganese-based sorbents. Annual report, September 1992--September 1993

    SciTech Connect

    Hepworth, M.T.

    1993-12-01

    The focus of work being performed on Hot Coal Gas Desulfurization at the Morgantown Energy Technology Center is primarily in the use of zinc ferrite and zinc titanate sorbents; however, prior studies at the US Steel Fundamental Research Laboratories in Monroeville, PA, by E. T. Turkdogan indicated that an alternate sorbent, manganese dioxide-containing ore in mixture with alumina (75 wt % ore + 25 wt % Al{sub 2}O{sub 3}) may be a viable alternative to zinc-based sorbents. Manganese, for example, has a lower vapor pressure in the elemental state than zinc hence it is not as likely to undergo depletion from the sorbent surface upon loading and regeneration cycles. Also manganese oxide is less readily reduced to the elemental state than iron hence the range of reduction potentials for oxygen is somewhat greater than for zinc ferrite. In addition, thermodynamic analysis of the manganese-oxygen-sulfur system shows it to be less amenable to sulfation than zinc ferrite. Potential also exists for utilization of manganese at higher temperatures than zinc ferrite or zinc titanate. This Annual Topical Report documents progress in pelletizing and testing via thermo-gravimetric analysis of individual pellet formulations of manganese ore/ alumina combinations and also manganese carbonate/alumina with two binders, dextrin and bentonite. It includes the prior Quarterly Technical Reports which indicate that the manganese carbonate material, being of higher purity than the manganese ore, has a higher degree of sulfur capacity and more rapid absorption kinetics. A 2-inch fixed-bed reactor has been fabricated and is now ready for subjecting pellets to cyclic loading and regeneration.

  2. Hot Coal Gas Desulfurization with manganese based sorbents. Quarterly report, August 1, 1993--September 30, 1993

    SciTech Connect

    Hepworth, M.T.

    1993-10-01

    The focus of work being performed on Hot Coal Gas Desulfurization at the Morgantown Energy Technology Center is primarily in the use of zinc ferrite and zinc titanate sorbents; however, prior studies at the US Steel Fundamental Research Laboratories in Monroeville, PA, by E. T. Turkdogan indicated that an alternate sorbent, manganese dioxide-containing ore in mixture with alumina (75 wt % ore + 25 wt % Al{sub 2}O{sub 3}) may be a viable alternative to zinc-based sorbents. Manganese, for example, has a lower vapor pressure in the elemental state than zinc hence it is not as likely to undergo depletion from the sorbent surface upon loading and regeneration cycles. Also manganese oxide is less readily reduced to the elemental state than iron hence the range of reduction potentials for oxygen is somewhat greater than for zinc ferrite. In addition, thermodynamic analysis of the manganese-oxygen-sulfur system shows it to be less amenable to sulfation than zinc ferrite. Potential also exists for utilization of manganese at higher temperatures than zinc ferrite or zinc titanate. This report documents progress in pelletizing and testing via thermogravimetric analysis of individual pellet formulations of manganese ore/alumina combinations and also manganese carbonate/alumina with two binders, dextrin and bentonite. Preliminary results indicate that the manganese carbonate material, being of higher purity than the manganese ore, has a higher degree of sulfur capacity and more rapid absorption kinetics. A 2-inch fixed-bed reactor has been fabricated and is now ready for subjecting pellets to cyclic loading and regeneration.

  3. Hot Corrosion Behavior of Arc-Sprayed Highly Dense NiCr-Based Coatings in Chloride Salt Deposit

    NASA Astrophysics Data System (ADS)

    Qin, Enwei; Yin, Song; Ji, Hua; Huang, Qian; Liu, Zekun; Wu, Shuhui

    2017-03-01

    To make cities more environmentally friendly, combustible wastes tend to be incinerated in waste-to-energy power plant boilers. However, release of chlorine gas (Cl2) during incineration causes serious problems related to hot corrosion of boiler tubes and poses a safety threat for such plants. In this study, a pseudo-de Laval nozzle was employed in a twin-wire arc spray system to enhance the velocity of in-flight particles. Highly dense NiCr-based coatings were obtained using the modified nozzle gun. The coating morphology was characterized by optical microscopy and scanning electron microscopy, and hot corrosion testing was carried out in a synthetic molten chloride salt environment. Results showed that the dense NiCr-based coatings exhibited high resistance against corrosion by chlorine, which can be related to the typical splat lamellar microstructure and chemical composition as well as minor alloying elements such as Ti and Mo.

  4. Microstructure and mechanical properties of hip-consolidated Rene 95 powders. [hot-isostatic pressed nickel-based powder metal

    NASA Technical Reports Server (NTRS)

    Shimanuki, Y.; Nishino, Y.; Masui, M.; Doi, H.

    1980-01-01

    The effects of heat-treatments on the microstructure of P/M Rene 95 (a nickel-based powder metal), consolidated by the hot-isostatic pressing (HIP), were examined. The microstructure of as-HIP'd specimen was characterized by highly serrated grain boundaries. Mechanical tests and microstructural observations reveal that the serrated grain boundaries improved ductility at both room and elevated temperatures by retarding crack propagation along grain boundaries.

  5. Convenient microtiter plate-based, oxygen-independent activity assays for flavin-dependent oxidoreductases based on different redox dyes

    PubMed Central

    Brugger, Dagmar; Krondorfer, Iris; Zahma, Kawah; Stoisser, Thomas; Bolivar, Juan M; Nidetzky, Bernd; Peterbauer, Clemens K; Haltrich, Dietmar

    2014-01-01

    Flavin-dependent oxidoreductases are increasingly recognized as important biocatalysts for various industrial applications. In order to identify novel activities and to improve these enzymes in engineering approaches, suitable screening methods are necessary. We developed novel microtiter-plate-based assays for flavin-dependent oxidases and dehydrogenases using redox dyes as electron acceptors for these enzymes. 2,6-dichlorophenol-indophenol, methylene green, and thionine show absorption changes between their oxidized and reduced forms in the visible range, making it easy to judge visually changes in activity. A sample set of enzymes containing both flavoprotein oxidases and dehydrogenases – pyranose 2-oxidase, pyranose dehydrogenase, cellobiose dehydrogenase, d-amino acid oxidase, and l-lactate oxidase – was selected. Assays for these enzymes are based on a direct enzymatic reduction of the redox dyes and not on the coupled detection of a reaction product as in the frequently used assays based on hydrogen peroxide formation. The different flavoproteins show low Michaelis constants with these electron acceptor substrates, and therefore these dyes need to be added in only low concentrations to assure substrate saturation. In conclusion, these electron acceptors are useful in selective, reliable and cheap MTP-based screening assays for a range of flavin-dependent oxidoreductases, and offer a robust method for library screening, which could find applications in enzyme engineering programs. PMID:24376171

  6. Kiln for hot-pressing compacts in a continuous manner

    DOEpatents

    Reynolds, C.D Jr.

    1983-08-08

    The invention is directed to a hot pressing furnace or kiln which is capable of preheating, hot pressing, and cooling a plurality of articles in a sequential and continuous manner. The hot pressing furnace of the present invention comprises an elongated, horizontally disposed furnace capable of holding a plurality of displaceable pusher plates each supporting a die body loaded with refractory or ceramic material to be hot pressed. Each of these plates and the die body supported thereby is sequentially pushed through the preheating zone, a temperature stabilizing and a hot pressing zone, and a cooling zone so as to provide a continuous hot-pressing operation of a plurality of articles.

  7. Kiln for hot-pressing compacts in a continuous manner

    DOEpatents

    Reynolds, Jr., Carl D.

    1985-01-01

    The present invention is directed to a hot pressing furnace or kiln which is capable of preheating, hot pressing, and cooling a plurality of articles in a sequential and continuous manner. The hot pressing furnace of the present invention comprises an elongated, horizontally disposed furnace capable of holding a plurality of displaceable pusher plates each supporting a die body loaded with refractory or ceramic material to be hot pressed. Each of these plates and the die body supported thereby is sequentially pushed through the preheating zone, a temperature stabilizing and a hot pressing zone, and a cooling zone so as to provide a continuous hot-pressing operation of a plurality of articles.

  8. The Effect of Stress and Hot Corrosion on Nickel-Base Superalloys

    DTIC Science & Technology

    1985-03-01

    Inconel 718 round bar tensile specimen. 19 ’I.. FIC. . Experimental test apparatus. 20 The creep ...the corrosion attack. 3 33 77. -. IV. EXPERIMENTAL RESULTS AND DISCUSSION A. INCONEL 718 1. CREEP BEHAVIOR Sustained-load creep tests were conducted at...of Inconel 718 were prepared for metrllographic examination after creep testing . Figure 18 shows dramatically the hot corrosion attack by a

  9. Hot embossed polyethylene through-hole chips for bead-based microfluidic devices

    PubMed Central

    Chou, Jie; Du, Nan; Ou, Tina; Floriano, Pierre N.; Christodoulides, Nicolaos; McDevitt, John T.

    2013-01-01

    Over the past decade, there has been a growth of interest in the translation of microfluidic systems into real-world clinical practice, especially for use in point-of-care or near patient settings. While initial fabrication advances in microfluidics involved mainly the etching of silicon and glass, the economics of scaling of these materials is not amendable for point-of-care usage where single-test applications forces cost considerations to be kept low and throughput high. As such, a materials base more consistent with point-of-care needs is required. In this manuscript, the fabrication of a hot embossed, through-hole low-density polyethylene ensembles derived from an anisotropically etched silicon wafer is discussed. This semi-opaque polymer that can be easily sterilized and recycled provides low background noise for fluorescence measurements and yields more affordable cost than other thermoplastics commonly used for microfluidic applications such as cyclic olefin copolymer (COC). To fabrication through-hole microchips from this alternative material for microfluidics, a fabrication technique that uses a high-temperature, high-pressure resistant mold is described. This aluminum-based epoxy mold, serving as the positive master mold for embossing, is casted over etched arrays of pyramidal pits in a silicon wafer. Methods of surface treatment of the wafer prior to casting and PDMS casting of the epoxy are discussed to preserve the silicon wafer for future use. Changes in the thickness of polyethylene are observed for varying embossing temperatures. The methodology described herein can quickly fabricate 20 disposable, single use chips in less than 30 minutes with the ability to scale up 4x by using multiple molds simultaneously. When coupled as a platform supporting porous bead sensors, as in the recently developed Programmable Bio-Nano-Chip, this bead chip system can achieve limits of detection, for the cardiac biomarker C-reactive protein, of 0.3 ng/mL, thereby

  10. KINETICS OF Mn-BASED SORBENTS FOR HOT COAL GAS DESULFURIZATION

    SciTech Connect

    J.J. BERNS; K.A. SADECKI; M.T. HEPWORTH

    1997-09-15

    Mixed manganese oxide sorbents have been investigated for high-temperature removal of hydrogen sulfide (the primary sulfur bearing compound) from hot coal gases. The sorbents were screened by thermodynamic equilibrium considerations for sulfidation. Preliminary experimental work using thermogravimetric analysis (TGA) indicated titania to be a superior substrate than alumina. Four formulations showing superior reactivity in a TGA were then tested in an ambient pressure fixed-bed reactor to determine steady state H 2 S concentrations, breakthrough times and effectiveness of the sorbent when subjected to cyclic sulfidation and regeneration testing. Eight tests were conducted with each test consisting of five cycles of sulfidation and regeneration. Sulfidation occurred at 600 o C using a simulated coal gas at an empty-bed space velocity of approximately 12,000 per hour. Manganese-based sorbents with molar ratios > 1:1 Mn:Substrate were effective in reducing the H 2 S concentration in simulated coal gases to less than 100 ppmv over five cycles. Actual breakthrough time for formulation C6-2-1100 was as high as 73% of breakthrough time based on wt% Mn in sorbent at 600 o C. Regeneration tests determined that loaded pellets can be essentially completely regenerated in an air/steam mixture at 750 o C with minimal sulfate formation. The leading formulation (designated C6-2) from the fixed-bed tests was then further tested under varying sorbent induration temperature, sulfidation temperature and superficial gas velocity. Four tests were conducted with each test consisting of four cycles of sulfidation and regeneration. Results showed that the induration temperature of the sorbent and the reaction temperature greatly affected the H 2 S removal capacity of the sorbent while the superficial gas velocity between 1090 and 1635 cm/min had minimal affect on the sorbent's breakthrough capacity. Testing showed that the sorbent's strength was a strong function of the sorbent induration

  11. Hot embossed polyethylene through-hole chips for bead-based microfluidic devices.

    PubMed

    Chou, Jie; Du, Nan; Ou, Tina; Floriano, Pierre N; Christodoulides, Nicolaos; McDevitt, John T

    2013-04-15

    Over the past decade, there has been a growth of interest in the translation of microfluidic systems into real-world clinical practice, especially for use in point-of-care or near patient settings. While initial fabrication advances in microfluidics involved mainly the etching of silicon and glass, the economics of scaling of these materials is not amendable for point-of-care usage where single-test applications force cost considerations to be kept low and throughput high. As such, materials base more consistent with point-of-care needs is required. In this manuscript, the fabrication of a hot embossed, through-hole low-density polyethylene ensembles derived from an anisotropically etched silicon wafer is discussed. This semi-opaque polymer that can be easily sterilized and recycled provides low background noise for fluorescence measurements and yields more affordable cost than other thermoplastics commonly used for microfluidic applications such as cyclic olefin copolymer (COC). To fabrication through-hole microchips from this alternative material for microfluidics, a fabrication technique that uses a high-temperature, high-pressure resistant mold is described. This aluminum-based epoxy mold, serving as the positive master mold for embossing, is casted over etched arrays of pyramidal pits in a silicon wafer. Methods of surface treatment of the wafer prior to casting and PDMS casting of the epoxy are discussed to preserve the silicon wafer for future use. Changes in the thickness of polyethylene are observed for varying embossing temperatures. The methodology described herein can quickly fabricate 20 disposable, single use chips in less than 30 min with the ability to scale up 4 times by using multiple molds simultaneously. When coupled as a platform supporting porous bead sensors, as in the recently developed Programmable Bio-Nano-Chip, this bead chip system can achieve limits of detection, for the cardiac biomarker C-reactive protein, of 0.3 ng/mL, thereby

  12. Development of a plate-based optical biosensor fragment screening methodology to identify phosphodiesterase 10A inhibitors.

    PubMed

    Geschwindner, Stefan; Dekker, Niek; Horsefield, Rob; Tigerström, Anna; Johansson, Patrik; Scott, Clay W; Albert, Jeffrey S

    2013-04-25

    We describe the development of a novel fragment screening methodology employing a plate-based optical biosensor system that can operate in a 384-well format. The method is based on the "inhibition in solution assay" (ISA) approach using an immobilized target definition compound (TDC) that has been specifically designed for this purpose by making use of available structural information. We demonstrate that this method is robust and is sufficiently sensitive to detect fragment hits as weak as KD 500 μM when confirmed in a conventional surface plasmon resonance approach. The application of the plate-based screen, the identification of fragment inhibitors of PDE10A, and their structural characterization are all discussed in a forthcoming paper.

  13. A high-throughput microtiter plate based method for the determination of peracetic acid and hydrogen peroxide.

    PubMed

    Putt, Karson S; Pugh, Randall B

    2013-01-01

    Peracetic acid is gaining usage in numerous industries who have found a myriad of uses for its antimicrobial activity. However, rapid high throughput quantitation methods for peracetic acid and hydrogen peroxide are lacking. Herein, we describe the development of a high-throughput microtiter plate based assay based upon the well known and trusted titration chemical reactions. The adaptation of these titration chemistries to rapid plate based absorbance methods for the sequential determination of hydrogen peroxide specifically and the total amount of peroxides present in solution are described. The results of these methods were compared to those of a standard titration and found to be in good agreement. Additionally, the utility of the developed method is demonstrated through the generation of degradation curves of both peracetic acid and hydrogen peroxide in a mixed solution.

  14. A cost-effective plate-based sample preparation for antibody N-glycan analysis.

    PubMed

    Burnina, Irina; Hoyt, Erik; Lynaugh, Heather; Li, Huijuan; Gong, Bing

    2013-09-13

    During early cell line and process development of therapeutic antibodies, a cost-effective high-throughput approach to characterize the N-linked glycans is highly desired given that a large number of samples need to be analyzed. Using commercially available, low cost 96-well plates, we developed a practical procedure to prepare fluorescently labeled N-linked glycans for both qualitative and quantitative analysis by mass spectrometry (MS) and ultrahigh performance liquid chromatography (UPLC). Antibody samples were continuously denatured, reduced, and deglycosylated in a single 96-well hydrophobic membrane filter plate. Subsequently, released glycans were fluorescently labeled in a collection plate, and cleaned-up using a hydrophilic membrane filter plate. Carried out entirely in ready-to-use 96-well plates with simple buffer systems, this procedure requires less than 90min to finish. We applied the optimized procedure to examine the N-linked glycosylation of trastuzumab and were able to quantify ten major N-linked glycans. The results from different amounts of starting materials (10-200μg) were highly similar and showed the robustness of this procedure. Compared to other methods, this new procedure is simple to implement, economically more affordable, and could be very valuable for early screenings of antibody development.

  15. Development of a novel bead-based 96-well filtration plate competitive immunoassay for the detection of Gentamycin.

    PubMed

    Ho, Tien Yu Jessica; Chan, Chia-Chung; Chan, KinGho; Wang, Yu Chieh; Lin, Jing-Tang; Chang, Cheng-Ming; Chen, Chien-Sheng

    2013-11-15

    We developed a sensitive, simple, inexpensive and rapid bead-based immunoassay platform, composed of liposomal nanovesicle amplification system, Gentamycin sulfate beads and 96-well filtration plates. In the beginning of the assay, Gentamycin sulfate beads, Gentamycin sulfate and Gentamycin specific antibody were incubated in a bottom-sealed 96-well filtration plate. After incubation, washing was done by running washing buffer through the unsealed filtration plate with only gravity and the antibody-Gentamycin bead complexes were retained in the plate. Fluorescent dye-loaded protein G-liposomal nanovesicles were then added to specifically bind to antibodies on the retained beads. After washing unbound nanovesicles, millions of fluorescent dye molecules were released by adding a detergent solution to lyse liposomal nanovesicles. The limit of detection (LOD) of this novel detection platform in TBS and in skim milk were 52.65 ng/mL and 14.16 ng/mL, which are both sufficient for detecting the 200 ng/mL Codex maximum residual level (MRL). The dynamic ranges were both from each of their LODs to 100 μg/mL. The 50% inhibition concentrations (IC50) in TBS and skim milk were 199.66 ng/mL and 360.81 ng/mL, respectively. We also demonstrated the good specificity of this platform by comparing detection results between pure Gentamycin solution and a mixture solution of 6 different antibiotics including Gentamycin in skim milk. The entire assay with 60 samples was conducted within 2h. In sum, this novel biosensing platform not only fulfilled most benefits of magnetic bead-based assays, but also was inexpensive and convenient by replacing the magnetic separation with filtration plate separation.

  16. Hot Coal Gas Desulfurization with manganese-based sorbents. Second [quarterly] technical report, December 1, 1992--March 1, 1993

    SciTech Connect

    Hepworth, M.T.

    1993-03-01

    At present, the focus of work being performed on Hot Coal Gas Desulfurization is primarily in the use of zinc ferrite and zinc titanate sorbents; however studies at the US Steel Fundamental Research Laboratories in Monroeville, PA, by E. T. Turkdogan indicate that an alternate sorbent, manganese dioxide-containing ore in mixture with alumina (75 wt % ore + 25 wt % Al{sub 2}O{sub 3}) may be a preferable alternative to zinc-based sorbents. A significant domestic source of manganese in Minnesota is being explored for an in situ leach process which has potential for producing large tonnages of solutions which may be ideal for precipitation and recovery of pure manganese as a carbonate in a reactive form. In the current program the following studies will be addressed: Preparation of manganese sorbent pellets and characterization tests on pellets for strength and surface area; analysis of the thermodynamics and kinetics of sulfur removal from hot fuel gases by individual sorbent pellets (loading tests) by thermogravimetric testing; regeneration tests via TGA on individual sorbent pellets by oxidation; and bench-scale testing on sorbent beds in a two-inch diameter reactor. The developed information will be of value to METC in its determination of whether or not a manganese-based regenerable sorbent holds real promise for sulfur cleanup of hot fuel gases. This information is necessary prior to pilot-scale testing leading to commercial development is undertaken.

  17. Fiber optic hot-wire flowmeter based on a metallic coated hybrid long period grating/fiber Bragg grating structure.

    PubMed

    Caldas, Paulo; Jorge, Pedro A S; Rego, Gaspar; Frazão, Orlando; Santos, José Luís; Ferreira, Luís Alberto; Araújo, Francisco

    2011-06-10

    In this work an all-optical hot-wire flowmeter based on a silver coated fiber combining a long period grating and a fiber Bragg grating (FBG) structure is proposed. Light from a pump laser at 1480  nm propagating down the fiber is coupled by the long period grating into the fiber cladding and is absorbed by the silver coating deposited on the fiber surface over the Bragg grating structure. This absorption acts like a hot wire raising the fiber temperature locally, which is effectively detected by the FBG resonance shift. The temperature increase depends on the flow speed of the surrounding air, which has the effect of cooling the fiber. It is demonstrated that the Bragg wavelength shift can be related to the flow speed. A flow speed resolution of 0.08  m/s is achieved using this new configuration.

  18. High gas velocity oxidation and hot corrosion testing of oxide dispersion-strengthened nickel-base alloys

    NASA Technical Reports Server (NTRS)

    Deadmore, D. L.; Lowell, C. E.

    1975-01-01

    Several oxide dispersion strengthened (ODS) nickel-base alloys were tested in high velocity gases for cyclic oxidation resistance at temperatures to 1200 C and times to 500 hours and for hot corrosion resistance at 900 C for 200 hours. Nickel-chromium-aluminum ODS alloys were found to have superior resistance to oxidation and hot corrosion when compared to bare and coated nickel-chromium ODS alloys. The best of the alloys tested had compositions of nickel - 15.5 to 16 weight percent chromium with aluminum weight percents between 4.5 and 5.0. All of the nickel-chromium-aluminum ODS materials experienced small weight losses (less than 16 mg/sq cm).

  19. A multiple linear regression analysis of hot corrosion attack on a series of nickel base turbine alloys

    NASA Technical Reports Server (NTRS)

    Barrett, C. A.

    1985-01-01

    Multiple linear regression analysis was used to determine an equation for estimating hot corrosion attack for a series of Ni base cast turbine alloys. The U transform (i.e., 1/sin (% A/100) to the 1/2) was shown to give the best estimate of the dependent variable, y. A complete second degree equation is described for the centered" weight chemistries for the elements Cr, Al, Ti, Mo, W, Cb, Ta, and Co. In addition linear terms for the minor elements C, B, and Zr were added for a basic 47 term equation. The best reduced equation was determined by the stepwise selection method with essentially 13 terms. The Cr term was found to be the most important accounting for 60 percent of the explained variability hot corrosion attack.

  20. Wetting reaction of Sn-Ag based solder systems on Cu substrates plated with Au and/or Pd layer

    NASA Astrophysics Data System (ADS)

    Liu, C. Y.; Li, Jian; Vandentop, G. J.; Choi, W. J.; Tu, K. N.

    2001-05-01

    The wetting behavior of SnAg based Pb-free solders on Cu and Cu substrates plated with Au, Pd, and Au/Pd thin films have been studied. The wetting angle and kinetics of interfacial reaction were measured. The Au-plated substrates exhibit better wetting than the Pd-plated substrates. In the case of SnAg on Pd-plated Cu, SEM observation revealed that the solder cap was surrounded by an innerring of Cu-Sn compound and an outer ring of Pd-Sn compound. This implies that the molten SnAg solder had removed the Pd and wetted the Cu directly in the equilibrium state. The effects of pre-doping Cu in the SnAg solder on wetting behavior were also investigated. We found that wettability decreases with increasing Cu content in the solder. We also observed that the SnAgCu solders have a lower Cu consumption rate than the SnAg solder.

  1. Homogeneous plate based antibody internalization assay using pH sensor fluorescent dye.

    PubMed

    Nath, Nidhi; Godat, Becky; Zimprich, Chad; Dwight, Stephen J; Corona, Cesear; McDougall, Mark; Urh, Marjeta

    2016-04-01

    Receptor-mediated antibody internalization is a key mechanism underlying several anti-cancer antibody therapeutics. Delivering highly toxic drugs to cancer cells, as in the case of antibody drug conjugates (ADCs), efficient removal of surface receptors from cancer cells and changing the pharmacokinetics profile of the antibody drugs are some of key ways that internalization impacts the therapeutic efficacy of the antibodies. Over the years, several techniques have been used to study antibody internalization including radiolabels, fluorescent microscopy, flow cytometry and cellular toxicity assays. While these methods allow analysis of internalization, they have limitations including a multistep process and limited throughput and are generally endpoint assays. Here, we present a new homogeneous method that enables time and concentration dependent measurements of antibody internalization. The method uses a new hydrophilic and bright pH sensor dye (pHAb dye), which is not fluorescent at neutral pH but becomes highly fluorescent at acidic pH. For receptor mediated antibody internalization studies, antibodies against receptors are conjugated with the pHAb dye and incubated with the cells expressing the receptors. Upon binding to the receptor, the dyes conjugated to the antibody are not fluorescent because of the neutral pH of the media, but upon internalization and trafficking into endosomal and lysosomal vesicles the pH drops and dyes become fluorescent. The enabling attributes of the pHAb dyes are the hydrophilic nature to minimize antibody aggregation and bright fluorescence at acidic pH which allows development of simple plate based assays using a fluorescent reader. Using two different therapeutic antibodies--Trastuzumab (anti-HER2) and Cetuximab (anti-EGFR)--we show labeling with pHAb dye using amine and thiol chemistries and impact of chemistry and dye to antibody ration on internalization. We finally present two new approaches using the pHAb dye, which will be

  2. Early state damage detection of aluminum 7075-T6 plate based on acoustic emission

    NASA Astrophysics Data System (ADS)

    Ozevin, Didem; Li, Zhong; Heidary, Zahra

    2011-04-01

    Aluminum alloy 7075-T6 is a commonly used material in aircraft industry. A crack usually initiates at the edge of a fastener hole, and it can affect the maintenance schedule and reduce the life of an aircraft structure significantly. The fatigue property of the material has been researched widely to develop methods and models for predicting fatigue crack growth under random loading. From the point of damage tolerance design, the inspection technique of a crack for an aircraft structure is very important because it can be used to determine the inspection period of the aircraft structure. The acoustic emission (AE) technique is a nondestructive testing (NDT) method that is able to monitor damage initiation and progression in real time. Understanding the early stage of AE signature due to the damage progression using small scale laboratory samples requires non-traditional data analysis approaches. In this study, 1mm thick Al-7075-T6 plates were tested under monotonic and fatigue loading. The initiation of damage progression using AE data was identified based on improved linear location algorithm and the result was verified using elasto-plastic finite element model. The improved location algorithm integrates dispersive characteristics of flexural waves and threshold independent approach to pick up the wave arrival time. In this paper, AE results in comparison with FE model under monotonic and fatigue loading will be presented. The comparison of traditional and improved location approaches will be shown. The approach for implementing the laboratory scale results in the large scale field testing will be discussed.

  3. The estimation of material and patch parameters in a PDE-based circular plate model

    NASA Technical Reports Server (NTRS)

    Banks, H. T.; Smith, Ralph C.; Brown, D. E.; Metcalf, Vern L.; Silcox, R. J.

    1995-01-01

    The estimation of material and patch parameters for a system involving a circular plate, to which piezoceramic patches are bonded, is considered. A partial differential equation (PDE) model for the thin circular plate is used with the passive and active contributions form the patches included in the internal and external bending moments. This model contains piecewise constant parameters describing the density, flexural rigidity, Poisson ratio, and Kelvin-Voigt damping for the system as well as patch constants and a coefficient for viscous air damping. Examples demonstrating the estimation of these parameters with experimental acceleration data and a variety of inputs to the experimental plate are presented. By using a physically-derived PDE model to describe the system, parameter sets consistent across experiments are obtained, even when phenomena such as damping due to electric circuits affect the system dynamics.

  4. An automatic system for measurement of retardation of wave plates based on phase-shifted method

    NASA Astrophysics Data System (ADS)

    Gao, Zhishan; Yan, Ming

    2005-02-01

    A practical system is described to measure the retardation of wave plates with phase-shifted method. The tested wave plate is put in and the original angle between the axis of it and the analyzer is random, not 45 degree. For the measurement is made rapidly and automatically, a standard wave plate act as a compensator, the stepping motor is used to drive the analyzer to realize phase shifting and a grating encoder is used to measure its rotating angle. At the same time, while the beam comes out from the analyzer, the photoelectric detector gets its intensity, and then the signals is magnified, filtered and sent to computer through its serial port. The results show the system has the advantages of costing little time and high accuracy.

  5. A comparison of field-dependent rheological properties between spherical and plate-like carbonyl iron particles-based magneto-rheological fluids

    NASA Astrophysics Data System (ADS)

    Tan Shilan, Salihah; Amri Mazlan, Saiful; Ido, Yasushi; Hajalilou, Abdollah; Jeyadevan, Balachandran; Choi, Seung-Bok; Azhani Yunus, Nurul

    2016-09-01

    This work proposes different sizes of the plate-like particles from conventional spherical carbonyl iron (CI) particles by adjusting milling time in the ball mill process. The ball mill process to make the plate-like particles is called a solid-state powder processing technique which involves repeated welding, fracturing and re-welding of powder particles in a high-energy ball mill. The effect of ball milling process on the magnetic behavior of CI particles is firstly investigated by vibrating sample magnetometer. It is found form this investigation that the plate-like particles have higher saturation magnetization (about 8%) than that of the spherical particles. Subsequently, for the investigation on the sedimentation behavior the cylindrical measurement technique is used. It is observed from this measurement that the plate-like particles show slower sedimentation rate compared to the spherical particles indicating higher stability of the MR fluid. The field-dependent rheological properties of MR fluids based on the plate-like particles are then investigated with respect to the milling time which is directly connected to the size of the plate-like particles. In addition, the field-dependent rheological properties such as the yield stress are evaluated and compared between the plate-like particles based MR fluids and the spherical particles based MR fluid. It is found that the yield shear stress of the plate-like particles based MR fluid is increased up to 270% compared to the spherical particles based MR fluid.

  6. Terahertz microfluidic sensor based on a parallel-plate waveguide resonant cavity

    NASA Astrophysics Data System (ADS)

    Mendis, Rajind; Astley, Victoria; Liu, Jingbo; Mittleman, Daniel M.

    2009-10-01

    We describe a terahertz optical resonator that is ideally suited for highly sensitive and noninvasive refractive-index monitoring. The resonator is formed by machining a rectangular groove into one plate of a parallel-plate waveguide, and is excited using the lowest-order transverse-electric (TE1) waveguide mode. Since the resonator can act as a channel for fluid flow, it can be easily integrated into a microfluidics platform for real-time monitoring. Using this resonator with only a few microliters of liquid, we demonstrate a refractive-index sensitivity of 3.7×105 nm/refractive-index-unit, the highest ever reported in any frequency range.

  7. Characterization and fixed-bed testing of a nickel-based hot gas desulfurization sorbent

    SciTech Connect

    Gasper-Galvin, L.D.; Swisher, J.H.; Hammerbeck, K.

    1994-10-01

    The objective of this project was to (1) extend a preliminary investigation completed earlier on dispersed nickel sorbents by developing new processing methods, characterizing sorbent materials more extensively, and evaluating the materials in fixed bed reactor tests, and (2) to determine the feasibility of using dispersed nickel sorbents with reductive regeneration for hot gas desulfurization. One of the properties of nickel that is somewhat unique is that it forms a liquid sulfide at sufficiently high temperatures with high sulfur potentials or H{sub 2}S levels. A eutectic exists in the Ni-S phase diagram at 637 C and a composition of 33.4 wt% or 21.5 wt% S. Under controlled conditions, the formation of a liquid phase can be used to advantage in hot gas desulfurization. Sorbent preparation, the experimental unit, and experimental procedure are described. Results from the sorbent, 24Ni-7Cu-Al{sub 2}O{sub 3}, are given.

  8. Development of a fluorometric microtiter plate based enzyme assay for MPS IVA (Morquio type A) using dried blood spots.

    PubMed

    Ullal, Anirudh J; Millington, David S; Bali, Deeksha S

    2014-01-01

    Mucopolysaccharidosis type IVA or Morquio type-A disease is a hereditary lysosomal storage disorder caused by deficient activity of the lysosomal enzyme N-acetylgalactosamine-6-sulfate sulfatase (GALNS). The disease is caused by lysosomal accumulation of unprocessed glycosaminoglycans (GAGs) that manifests with severe to mild skeletal and cardiopulmonary abnormalities. We have developed a modified microtiter plate-based enzyme activity assay using dried blood spots and a fluorescent substrate for measuring specific GALNS activity to identify patients with MPS IVA.

  9. Solar Hot Water Heater

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The solar panels pictured below, mounted on a Moscow, Idaho home, are part of a domestic hot water heating system capable of providing up to 100 percent of home or small business hot water needs. Produced by Lennox Industries Inc., Marshalltown, Iowa, the panels are commercial versions of a collector co-developed by NASA. In an effort to conserve energy, NASA has installed solar collectors at a number of its own facilities and is conducting research to develop the most efficient systems. Lewis Research Center teamed with Honeywell Inc., Minneapolis, Minnesota to develop the flat plate collector shown. Key to the collector's efficiency is black chrome coating on the plate developed for use on spacecraft solar cells, the coating prevents sun heat from "reradiating," or escaping outward. The design proved the most effective heat absorber among 23 different types of collectors evaluated in a Lewis test program. The Lennox solar domestic hot water heating system has three main components: the array of collectors, a "solar module" (blue unit pictured) and a conventional water heater. A fluid-ethylene glycol and water-is circulated through the collectors to absorb solar heat. The fluid is then piped to a double-walled jacket around a water tank within the solar module.

  10. Saturn's Hot Plasma Explosions

    NASA Video Gallery

    This animation based on data obtained by NASA's Cassini Spacecraft shows how the "explosions" of hot plasma on the night side (orange and white) periodically inflate Saturn's magnetic field (white ...

  11. Surface-plasmon enhanced photodetection at communication band based on hot electrons

    SciTech Connect

    Wu, Kai; Zhan, Yaohui E-mail: xfli@suda.edu.cn; Wu, Shaolong; Deng, Jiajia; Li, Xiaofeng E-mail: xfli@suda.edu.cn

    2015-08-14

    Surface plasmons can squeeze light into a deep-subwavelength space and generate abundant hot electrons in the nearby metallic regions, enabling a new paradigm of photoconversion by the way of hot electron collection. Unlike the visible spectral range concerned in previous literatures, we focus on the communication band and design the infrared hot-electron photodetectors with plasmonic metal-insulator-metal configuration by using full-wave finite-element method. Titanium dioxide-silver Schottky interface is employed to boost the low-energy infrared photodetection. The photodetection sensitivity is strongly improved by enhancing the plasmonic excitation from a rationally engineered metallic grating, which enables a strong unidirectional photocurrent. With a five-step electrical simulation, the optimized device exhibits an unbiased responsivity of ∼0.1 mA/W and an ultra-narrow response band (FWHM = 4.66 meV), which promises to be a candidate as the compact photodetector operating in communication band.

  12. Exploring the hot Neptune / super-Earth transition via ground-based transmission spectroscopy

    NASA Astrophysics Data System (ADS)

    Rackham, B.; Espinoza, N.; Apai, D.; Jordán, A.; López-Morales, M.; Fraine, J.; Lewis, N.; Rodler, F.; Fortney, J.; Osip, D.

    2014-03-01

    One of the most surprising results of the Kepler mission has been the abundance of super-Earths (1.25-2 R⊕) and Neptune-sized planets (2-6 R⊕), including the close-in “hot” Neptunes. Understanding the characteristics of these common exoplanets and the transition between them has important implications for astrobiology, as super-Earths may be suitable hosts for life, but Neptune-sized ice and gas giants are not. Distinguishing between the diversity of worlds that may exist at this transition requires measurements of the transmission spectra of their atmospheres. The recently launched Arizona-CfA-Católica Exoplanet Spectroscopy Survey (ACCESS) is addressing this need by compiling a uniform sample of exoplanet optical transmission spectra from hot Jupiters through hot Neptunes to super-Earths, enabling comparative studies of exoplanets over a wide range of masses, radii, and irradiation conditions. Here we present our first results from a planet at the hot Neptune / super-Earth transition: an optical transmission spectrum of GJ 1214b obtained during two transits with Magellan/IMACS. We discuss the experimental techniques used to collect the spectrum, the statistical methods employed in the data analysis, and the application of the optical spectrum to proposed models of GJ 1214b’s atmosphere.

  13. High loading uranium fuel plate

    DOEpatents

    Wiencek, Thomas C.; Domagala, Robert F.; Thresh, Henry R.

    1990-01-01

    Two embodiments of a high uranium fuel plate are disclosed which contain a meat comprising structured uranium compound confined between a pair of diffusion bonded ductile metal cladding plates uniformly covering the meat, the meat having a uniform high fuel loading comprising a content of uranium compound greater than about 45 Vol. % at a porosity not greater than about 10 Vol. %. In a first embodiment, the meat is a plurality of parallel wires of uranium compound. In a second embodiment, the meat is a dispersion compact containing uranium compound. The fuel plates are fabricated by a hot isostatic pressing process.

  14. Flat plate solar collector design and performance. Citations from the NTIS data base

    NASA Astrophysics Data System (ADS)

    Hundemann, A. S.

    1980-09-01

    Federally funded research on the design and thermal efficiency of air and liquid type flat plate collectors is discussed. Topic areas cover convection characteristics, methods to reduce heat loss, optical coatings, and corrosion control. Emphasis of the bibliography is on basic research studies. This updated bibliography contains 196 citations, 36 of which are new entries to the previous edition.

  15. Detailed measurements and shaping of gate profiles for microchannel-plate-based X-ray framing cameras

    SciTech Connect

    Landen, O.L.; Hammel, B.A.; Bell, P.M.; Abare, A. |; Bradley, D.K. |

    1994-10-03

    Gated, microchannel-plate-based (MCP) framing cameras are increasingly used worldwide for x-ray imaging of subnanosecond laser-plasma phenomena. Large dynamic range (> 1,000) measurements of gain profiles for gated microchannel plates (MCP) are presented. Temporal profiles are reconstructed for any point on the microstrip transmission line from data acquired over many shots with variable delay. No evidence for significant pulse distortion by voltage reflections at the ends of the microstrip is observed. The measured profiles compare well to predictions by a time-dependent discrete dynode model down to the 1% level. The calculations do overestimate the contrast further into the temporal wings. The role of electron transit time dispersion in limiting the minimum achievable gate duration is then investigated by using variable duration flattop gating pulses. A minimum gate duration of 50 ps is achieved with flattop gating, consistent with a fractional transit time spread of {approx} 15%.

  16. Acoustic emission source localization in thin metallic plates: A single-sensor approach based on multimodal edge reflections.

    PubMed

    Ebrahimkhanlou, A; Salamone, S

    2017-03-14

    This paper presents a new acoustic emission (AE) source localization for isotropic plates with reflecting boundaries. This approach that has no blind spot leverages multimodal edge reflections to identify AE sources with only a single sensor. The implementation of the proposed approach involves three main steps. First, the continuous wavelet transform (CWT) and the dispersion curves of the fundamental Lamb wave modes are utilized to estimate the distance between an AE source and a sensor. This step uses a modal acoustic emission approach. Then, an analytical model is proposed that uses the estimated distances to simulate the edge-reflected waves. Finally, the correlation between the experimental and the simulated waveforms is used to estimate the location of AE sources. Hsu-Nielsen pencil lead break (PLB) tests were performed on an aluminum plate to validate this algorithm and promising results were achieved. Based on these results, the paper reports the statistics of the localization errors.

  17. Wheelspace windage cover plate for turbine

    DOEpatents

    Lathrop, Norman Douglas

    2002-01-01

    Windage cover plates are secured between the wheels and spacer of a turbine rotor to prevent hot flow path gas ingestion into the wheelspace cavities. Each cover plate includes a linear, axially extending body curved circumferentially with a radially outwardly directed wall at one axial end. The wall defines a axially opening recess for receiving a dovetail lug. The cover plate includes an axially extending tongue received in a circumferential groove of the spacer. The cover plate is secured with the tongue in the groove and dovetail lug in the recess. Lap joints between circumferentially adjacent cover plates are provided.

  18. On 3-D inelastic analysis methods for hot section components (base program)

    NASA Technical Reports Server (NTRS)

    Wilson, R. B.; Bak, M. J.; Nakazawa, S.; Banerjee, P. K.

    1986-01-01

    A 3-D Inelastic Analysis Method program is described. This program consists of a series of new computer codes embodying a progression of mathematical models (mechanics of materials, special finite element, boundary element) for streamlined analysis of: (1) combustor liners, (2) turbine blades, and (3) turbine vanes. These models address the effects of high temperatures and thermal/mechanical loadings on the local (stress/strain)and global (dynamics, buckling) structural behavior of the three selected components. Three computer codes, referred to as MOMM (Mechanics of Materials Model), MHOST (Marc-Hot Section Technology), and BEST (Boundary Element Stress Technology), have been developed and are briefly described in this report.

  19. Parallel double-plate capacitive proximity sensor modelling based on effective theory

    NASA Astrophysics Data System (ADS)

    Li, Nan; Zhu, Haiye; Wang, Wenyu; Gong, Yu

    2014-02-01

    A semi-analytical model for a double-plate capacitive proximity sensor is presented according to the effective theory. Three physical models are established to derive the final equation of the sensor. Measured data are used to determine the coefficients. The final equation is verified by using measured data. The average relative error of the calculated and the measured sensor capacitance is less than 7.5%. The equation can be used to provide guidance to engineering design of the proximity sensors.

  20. Solar Sail - Fresnel Zone Plate Lens for a Large Space Based Telescope

    SciTech Connect

    Early, J T

    2002-02-13

    A Fresnel zone plate lens made with solar sail material could be used as the primary optic for a very large aperture telescope on deep space probes propelled by solar sails. The large aperture telescope capability could enable significant science on fly-by missions to the asteroids, Pluto, Kuiper belt or the tort cloud and could also enable meaningful interstellar fly-by missions for laser propelled sails. This type of lens may also have some potential for laser communications and as a solar concentrator. The techniques for fabrication of meter size and larger Fresnel phase plate optics are under development at LLNL, and we are extending this technology to amplitude zone plates made from sail materials. Corrector optics to greatly extend the bandwidth of these Fresnel optics will be demonstrated in the future. This novel telescope concept will require new understanding of the fabrication, deployment and control of gossamer space structures. It will also require new materials technology for fabricating these optics and understanding their long term stability in a space environment.

  1. Simulation of Bacillus subtilis biofilm growth on agar plate by diffusion-reaction based continuum model

    NASA Astrophysics Data System (ADS)

    Zhang, Xianlong; Wang, Xiaoling; Nie, Kai; Li, Mingpeng; Sun, Qingping

    2016-08-01

    Various species of bacteria form highly organized spatially-structured aggregates known as biofilms. To understand how microenvironments impact biofilm growth dynamics, we propose a diffusion-reaction continuum model to simulate the formation of Bacillus subtilis biofilm on an agar plate. The extended finite element method combined with level set method are employed to perform the simulation, numerical results show the quantitative relationship between colony morphologies and nutrient depletion over time. Considering that the production of polysaccharide in wild-type cells may enhance biofilm spreading on the agar plate, we inoculate mutant colony incapable of producing polysaccharide to verify our results. Predictions of the glutamate source biofilm’s shape parameters agree with the experimental mutant colony better than that of glycerol source biofilm, suggesting that glutamate is rate limiting nutrient for Bacillus subtilis biofilm growth on agar plate, and the diffusion-limited is a better description to the experiment. In addition, we find that the diffusion time scale is of the same magnitude as growth process, and the common-employed quasi-steady approximation is not applicable here.

  2. A quantitative damage imaging technique based on enhanced CCRTM for composite plates using 2D scan

    NASA Astrophysics Data System (ADS)

    He, Jiaze; Yuan, Fuh-Gwo

    2016-10-01

    A two-dimensional (2D) non-contact areal scan system was developed to image and quantify impact damage in a composite plate using an enhanced zero-lag cross-correlation reverse-time migration (E-CCRTM) technique. The system comprises a single piezoelectric wafer mounted on the composite plate and a laser Doppler vibrometer (LDV) for scanning a region in the vicinity of the PZT to capture the scattered wavefield. The proposed damage imaging technique takes into account the amplitude, phase, geometric spreading, and all of the frequency content of the Lamb waves propagating in the plate; thus, a reflectivity coefficients of the delamination is calculated and potentially related to damage severity. Comparisons are made in terms of damage imaging quality between 2D areal scans and 1D line scans as well as between the proposed and existing imaging conditions. The experimental results show that the 2D E-CCRTM performs robustly when imaging and quantifying impact damage in large-scale composites using a single PZT actuator with a nearby areal scan using LDV.

  3. Charge coupled devices vs. microchannel plates in the extreme and far ultraviolet - A comparison based on the latest laboratory measurements

    NASA Technical Reports Server (NTRS)

    Vallerga, J.; Lampton, M.

    1988-01-01

    While microchannel plates (MCPs) have been established as imaging photon counters in the EUV and FUV for some years, CCDs are associated with low light level sensing at visible and near-IR wavelengths. Attention is presently given to recent proposals for CCDs' use as EUV and FUV detectors with quantum efficiencies sometimes exceeding those of MCPs; quantum resolution, format size, dynamic range, and long-term stability are also used as bases of comparison, for the cases of both space-based astronomical and spectroscopic applications.

  4. Gap-plasmon based broadband absorbers for enhanced hot-electron and photocurrent generation

    NASA Astrophysics Data System (ADS)

    Lu, Yuhua; Dong, Wen; Chen, Zhuo; Pors, Anders; Wang, Zhenlin; Bozhevolnyi, Sergey I.

    2016-07-01

    Plasmonic hot-electron generation has recently come into focus as a new scheme for solar energy conversion. So far, however, due to the relatively narrow bandwidth of the surface plasmon resonances and the insufficient resonant light absorption, most of plasmonic photocatalysts show narrow-band spectral responsivities and small solar energy conversion efficiencies. Here we experimentally demonstrate that a three-layered nanostructure, consisting of a monolayer gold-nanoparticles and a gold film separated by a TiO2 gap layer (Au-NPs/TiO2/Au-film), is capable of near-completely absorbing light within the whole visible region. We show that the Au-NPs/TiO2/Au-film device can take advantage of such strong and broadband light absorption to enhance the generation of hot electrons and thus the photocurrent under visible irradiation. As compared to conventional plasmonic photocatalysts such as Au-NPs/TiO2 nanostructures, a 5-fold-enhanced incident photon-to-current conversion efficiency is achieved within the entire wavelength range 450–850 nm in the Au-NPs/TiO2/Au-film device. Simulations show good agreements with the experimental results, demonstrating that only the plasmon-induced losses contribute to the enhanced photocurrent generation of the Au-NPs/TiO2/Au-film device.

  5. Highly stable and regenerable Mn-based/SBA-15 sorbents for desulfurization of hot coal gas.

    PubMed

    Zhang, F M; Liu, B S; Zhang, Y; Guo, Y H; Wan, Z Y; Subhan, Fazle

    2012-09-30

    A series of mesoporous xCuyMn/SBA-15 sorbents with different Cu/Mn atomic ratios were prepared by wet impregnation method and their desulfurization performance in hot coal gas was investigated in a fixed-bed quartz reactor in the range of 700-850°C. The successive nine desulfurization-regeneration cycles at 800°C revealed that 1Cu9Mn/SBA-15 presented high performance with durable regeneration ability due to the high dispersion of Mn(2)O(3) particles incorporated with a certain amount of copper oxides. The breakthrough sulfur capacity of 1Cu9Mn/SBA-15 observed 800°C is 13.8 g S/100g sorbents, which is remarkably higher than these of 40 wt%LaFeO(3)/SBA-15 (4.8 g S/100g sorbents) and 50 wt%LaFe(2)O(x)/MCM-41 (5.58 g S/100g sorbents) used only at 500-550°C. This suggested that the loading of Mn(2)O(3) active species with high thermal stability to SBA-15 support significantly increased sulfur capacity at relatively higher sulfidation temperature. The fresh and used xCuyMn/SBA-15 sorbents were characterized by means of BET, XRD, XPS, XAES, TG/DSC and HRTEM techniques, confirmed that the structure of the sorbents remained intact before and after hot coal gas desulfurization.

  6. Gap-plasmon based broadband absorbers for enhanced hot-electron and photocurrent generation

    PubMed Central

    Lu, Yuhua; Dong, Wen; Chen, Zhuo; Pors, Anders; Wang, Zhenlin; Bozhevolnyi, Sergey I.

    2016-01-01

    Plasmonic hot-electron generation has recently come into focus as a new scheme for solar energy conversion. So far, however, due to the relatively narrow bandwidth of the surface plasmon resonances and the insufficient resonant light absorption, most of plasmonic photocatalysts show narrow-band spectral responsivities and small solar energy conversion efficiencies. Here we experimentally demonstrate that a three-layered nanostructure, consisting of a monolayer gold-nanoparticles and a gold film separated by a TiO2 gap layer (Au-NPs/TiO2/Au-film), is capable of near-completely absorbing light within the whole visible region. We show that the Au-NPs/TiO2/Au-film device can take advantage of such strong and broadband light absorption to enhance the generation of hot electrons and thus the photocurrent under visible irradiation. As compared to conventional plasmonic photocatalysts such as Au-NPs/TiO2 nanostructures, a 5-fold-enhanced incident photon-to-current conversion efficiency is achieved within the entire wavelength range 450–850 nm in the Au-NPs/TiO2/Au-film device. Simulations show good agreements with the experimental results, demonstrating that only the plasmon-induced losses contribute to the enhanced photocurrent generation of the Au-NPs/TiO2/Au-film device. PMID:27470207

  7. Plate-like structure health monitoring based on ultrasonic guided wave technology by using bonded piezoelectric ceramic wafers

    NASA Astrophysics Data System (ADS)

    Liu, Zenghua; Zhao, Jichen; He, Cunfu; Wu, Bin

    2008-11-01

    Piezoelectric ceramic wafers are applied for the excitation and detection of ultrasonic guided waves to determine the health state of plate-like structures. Two PZT wafers, whose diameter is 11mm and thickness is 0.4mm respectively, are bonded permanently on the surface of a 1mm thick aluminum plate. One of these wafers is actuated by sinusoidal tone burst at various frequencies ranging from 100kHz to 500kHz, the other one is used as a receiver for acquiring ultrasonic guided wave signals. According to the amplitudes and shapes of these received signals, guided wave modes and their proper frequency range by using these wafers are determined. For the improvement of the signal-to-noise ratio, the Daubechies wavelet of order 40 is used for signal denoising as the mother wavelet. Furthermore, the detection of an artificial cylindrical through-hole defect is achieved by using S0 at 300kHz. Experimental results show that it is feasible and effective to detect defects in plate-like structures based on ultrasonic guided wave technology by using bonded piezoelectric ceramic wafers.

  8. Development of carbon nanotube and graphite filled polyphenylene sulfide based bipolar plates for all-vanadium redox flow batteries

    NASA Astrophysics Data System (ADS)

    Caglar, Burak; Fischer, Peter; Kauranen, Pertti; Karttunen, Mikko; Elsner, Peter

    2014-06-01

    In this study, synthetic graphite and carbon nanotube (CNT) filled polyphenylene sulfide (PPS) based bipolar plates are produced by using co-rotating twin-screw extruder and injection molding. Graphite is the main conductive filler and CNTs are used as bridging filler between graphite particles. To improve the dispersion of the fillers and the flow behavior of the composite, titanate coupling agent (KR-TTS) is used. The concentration effect of CNTs and coupling agent on the properties of bipolar plates are examined. At 72.5 wt.% total conductive filler concentration, by addition of 2.5 wt.% CNT and 3 wt.% KR-TTS; through-plane and in-plane electrical conductivities increase from 1.42 S cm-1 to 20 S cm-1 and 6.4 S cm-1 to 57.3 S cm-1 respectively compared to sample without CNTs and additive. Extruder torque value and apparent viscosity of samples decrease significantly with coupling agent and as a result; the flow behavior is positively affected. Flexural strength is improved 15% by addition of 1.25 wt.% CNT. Differential scanning calorimeter (DSC) analysis shows nucleating effect of conductive fillers on PPS matrix. Corrosion measurements, cyclic voltammetry and galvanostatic charge-discharge tests are performed to examine the electrochemical stability and the performance of produced bipolar plates in all-vanadium redox flow battery.

  9. Neural Action Fields for Optic Flow Based Navigation: A Simulation Study of the Fly Lobula Plate Network

    PubMed Central

    Borst, Alexander; Weber, Franz

    2011-01-01

    Optic flow based navigation is a fundamental way of visual course control described in many different species including man. In the fly, an essential part of optic flow analysis is performed in the lobula plate, a retinotopic map of motion in the environment. There, the so-called lobula plate tangential cells possess large receptive fields with different preferred directions in different parts of the visual field. Previous studies demonstrated an extensive connectivity between different tangential cells, providing, in principle, the structural basis for their large and complex receptive fields. We present a network simulation of the tangential cells, comprising most of the neurons studied so far (22 on each hemisphere) with all the known connectivity between them. On their dendrite, model neurons receive input from a retinotopic array of Reichardt-type motion detectors. Model neurons exhibit receptive fields much like their natural counterparts, demonstrating that the connectivity between the lobula plate tangential cells indeed can account for their complex receptive field structure. We describe the tuning of a model neuron to particular types of ego-motion (rotation as well as translation around/along a given body axis) by its ‘action field’. As we show for model neurons of the vertical system (VS-cells), each of them displays a different type of action field, i.e., responds maximally when the fly is rotating around a particular body axis. However, the tuning width of the rotational action fields is relatively broad, comparable to the one with dendritic input only. The additional intra-lobula-plate connectivity mainly reduces their translational action field amplitude, i.e., their sensitivity to translational movements along any body axis of the fly. PMID:21305019

  10. Susceptibility to hot corrosion of four nickel-base superalloys, NASA-TRW VIA, B-1900, 713C and IN-738

    NASA Technical Reports Server (NTRS)

    Stearns, C. A.; Kohl, F. J.; Fryburg, G. C.

    1977-01-01

    The susceptibility to hot corrosion of four nickel-base, cast superalloys has been studied at 900 and 1000 C. The test consisted of coating alloy samples with known amounts of Na2SO4 and oxidizing the coated samples isothermally in 1 atmosphere of slowly flowing oxygen, the weight-gain being monitored on a sensitive recording microbalance. Susceptibility to hot corrosion decreased in the order of decreasing molybdenum content of the alloys. Preoxidation of samples before hot-corrosion testing markedly increased the induction period observed prior to the inception of hot corrosion for all alloys tested. X-ray diffraction analyses of the oxide scales were made. All samples that underwent hot corrosion showed the presence of a (Ni,Co)MoO4 layer near the alloy-oxide interface. Several specimens displayed resistance to hot corrosion and these showed NaTaO3 as a prominent feature in their oxide scale. Our results may be interpreted as indicating that molybdenum in an alloy is detrimental, with respect to hot corrosion, while tantalum is beneficial.

  11. A Thermodynamic Model for Predicting Phosphorus Partition between CaO-based Slags and Hot Metal during Hot Metal Dephosphorization Pretreatment Process Based on the Ion and Molecule Coexistence Theory

    NASA Astrophysics Data System (ADS)

    Yang, Xue-min; Li, Jin-yan; Chai, Guo-ming; Duan, Dong-ping; Zhang, Jian

    2016-08-01

    A thermodynamic model for predicting phosphorus partition L P between a CaO-based slags and hot metal during hot metal dephosphorization pretreatment process has been developed based on the ion and molecule coexistence theory (IMCT), i.e., the IMCT- L P model. The reaction abilities of structural units or ion couples in the CaO-based slags have been represented by the calculated mass action concentrations N i through the developed IMCT- N i model based on the IMCT. The developed IMCT- L P model has been verified to be valid through comparing with the measured L P as well as the predicted L P by two reported L P models from the literature. Besides the total phosphorus partition L P between the CaO-based slag and hot metal, the respective phosphorus partitions L P, i of nine dephosphorization products as P2O5, 3FeO·P2O5, 4FeO·P2O5, 2CaO·P2O5, 3CaO·P2O5, 4CaO·P2O5, 2MgO·P2O5, 3MgO·P2O5, and 3MnO·P2O5 can also be accurately predicted by the developed IMCT- L P model. The formed 3CaO·P2O5 accounts for 99.20 pct of dephosphorization products comparing with the generated 4CaO·P2O5 for 0.08 pct. The comprehensive effect of CaO+Fe t O, which can be described by the mass percentage ratio (pct Fe t O)/(pct CaO) or the mass action concentration ratio N_{Fe}t O/N_{Fe}t O N_{CaO}. N_{CaO}} as well as the mass percentage product (pct Fe t O) × (pct CaO) or the mass action concentration product N_{{{{Fe}}t {{O}}}}5 × N_{{CaO}}3 , controls dephosphorization ability of the CaO-based slags. A linear relationship of L P against (pct Fe t O)/(pct CaO) can be correlated compared with a parabolic relationship of L P against N_{Fe}t O/N_{Fe}t O N_{CaO}. N_{CaO}, while the linear relationship of L P against (pct Fe t O) × (pct CaO) or N_{Fe}t O5 × N_{CaO}3 can be established. Thus, the mass percentage product (pct Fe t O) × (pct CaO) and the mass action concentration product N_{Fe}t O5 × N_{CaO}3 are recommended to represent the comprehensive effect of CaO+Fe t O on

  12. Plate-mantle coupling from post-Pangea plate kinematics

    NASA Astrophysics Data System (ADS)

    Zahirovic, Sabin; Dietmar Müller, R.; Seton, Maria; Flament, Nicolas

    2015-04-01

    keels impinge on asthenospheric flow to increase shear traction, thus anchoring the plate in the more viscous mantle transition zone. However, plates with significant cratonic fragments exhibit short-lived (~10 Myr) accelerations, such as the rapid motion of the Indian plate that is correlated with plume head arrivals as recorded by large igneous province (LIPs) emplacement, highlighting the necessity to analyse plate velocities over long geological timeframes. By evaluating factors controlling plate velocities in the post-Pangea timeframe, simple principles can be applied to highlight potential plate velocity artefacts for Paleozoic and earlier times for which no hotspot tracks, nor in-situ seafloor spreading histories, are preserved. Based on the post-Pangea timeframe, a principle that can be applied to pre-Pangea times is that plates with less than ~50% continental area can reach RMS velocities of ~20 cm/yr, while plates with more than 50% continental fraction do not exceed RMS velocities of ~10 cm/yr. Similarly, plates with large portions of continental or cratonic area with RMS velocities exceeding ~15 cm/yr for more than ~10 Myr should be flagged as potential artefacts requiring further justification of plate driving forces in such scenarios.

  13. Graphene-based supercapacitors in the parallel-plate electrode configuration: ionic liquids versus organic electrolytes.

    PubMed

    Shim, Youngseon; Kim, Hyung J; Jung, Younjoon

    2012-01-01

    Supercapacitors with two single-sheet graphene electrodes in the parallel plate geometry are studied via molecular dynamics (MD) computer simulations. Pure 1-ethyl-3-methylimidazolium tetrafluoroborate (EMI+BF4-) and a 1.1 M solution of EMI+BF4- in acetonitrile are considered as prototypes of room-temperature ionic liquids (RTILs) and organic electrolytes. Electrolyte structure, charge density and associated electric potential are investigated by varying the charges and separation of the two electrodes. Multiple charge layers formed in the electrolytes in the vicinity of the electrodes are found to screen the electrode surface charge almost completely. As a result, the supercapacitors show nearly an ideal electric double layer behavior, i.e., the electric potential exhibits essentially a plateau behavior in the entire electrolyte region except for sharp changes in screening zones very close to the electrodes. Due to its small size and large charge separation, BF4- is considerably more efficient in shielding electrode charges than EMI+. In the case of the acetonitrile solution, acetonitrile also plays an important role by aligning its dipoles near the electrodes; however, the overall screening mainly arises from ions. Because of the disparity of shielding efficiency between cations and anions, the capacitance of the positively-charged anode is significantly larger than that of the negatively-charged cathode. Therefore, the total cell capacitance in the parallel plate configuration is primarily governed by the cathode. Ion conductivity obtained via the Green-Kubo (GK) method is found to be largely independent of the electrode surface charge. Interestingly, EMI+BF4- shows higher GK ion conductivity than the 1.1 M acetonitrile solution between two parallel plate electrodes.

  14. Preliminary design of a zone plate based hard X-ray monochromatic diffraction nanoprobe for materials studies at APS

    NASA Astrophysics Data System (ADS)

    Cai, Zhonghou; Liu, Wenjun; Tischler, Jonathan Z.; Shu, Deming; Xu, Ruqing; Schmidt, Oliver

    2013-09-01

    Aiming at studies of the micro/nano-structures of a broad range materials and electronic devices, Advance Photon Source (APS) is developing a dedicated diffraction nanoprobe (DNP) beamline for the needs arising from a multidiscipline research community. As a part of the APS Upgrade Project, the planed facility, named Sub-micron 3-D Diffraction (S3DD) beamline1, integrates the K-B mirror based polychromatic Laue diffraction and the Fresnel zone-plate based monochromatic diffraction techniques that currently support 3D/2D microdiffraction programs at the 34-ID-E and 2-ID-D of the APS, respectively. Both diffraction nanoprobes are designed to have a 50-nm or better special resolution. The zone-plate based monochromatic DNP has been preliminarily designed and will be constructed at the sector 34-ID. It uses an APS-3.0-cm period or APS-3.3-cm period undulator, a liquid-nitrogen cooled mirror as its first optics, and a water cooled small gap silicon double-crystal monochromator with an energy range of 5-30 keV. A set of zone plates have been designed to optimize for focusing efficiency and the working distance based on the attainable beamline length and the beam coherence. To ensure the nanoprobe performance, high stiffness and high precision flexure stage systems have been designed or demonstrated for optics mounting and sample scanning, and high precision temperature control of the experimental station will be implemented to reduce thermal instability. Designed nanoprobe beamline has a good management on thermal power loading on optical components and allows high degree of the preservation of beam brilliance for high focal flux and coherence. Integrated with variety of X-ray techniques, planed facility provides nano-XRD capability with the maximum reciprocal space accessibility and allows micro/nano-spectroscopy studies with K-edge electron binding energies of most elements down to Vanadium in the periodic table. We will discuss the preliminary design of the zone-plate

  15. Mechanism of hot electron electroluminescence in GaN-based transistors

    NASA Astrophysics Data System (ADS)

    Brazzini, Tommaso; Sun, Huarui; Sarti, Francesco; Pomeroy, James W.; Hodges, Chris; Gurioli, Massimo; Vinattieri, Anna; Uren, Michael J.; Kuball, Martin

    2016-11-01

    The nature of hot electron electroluminescence (EL) in AlGaN/GaN high electron mobility transistors is studied and attributed to Bremsstrahlung. The spectral distribution has been corrected, for the first time, for interference effects due to the multilayered device structure, and this was shown to be crucial for the correct interpretation of the data, avoiding artefacts in the spectrum and misinterpretation of the results. An analytical expression for the spectral distribution of emitted light is derived assuming Bremsstrahlung as the only origin and compared to the simplified exponential model for the high energy tail commonly used for electron temperature extraction: the electron temperature obtained results about 20% lower compared to the approximated exponential model. Comparison of EL intensity for devices from different wafers illustrated the dependence of EL intensity on the material quality. The polarization of electroluminescence also confirms Bremsstrahlung as the dominant origin of the light emitted, ruling out other possible main mechanisms.

  16. Simple but Strong: A Mussel-Inspired Hot Curing Adhesive Based on Polyvinyl Alcohol Backbone.

    PubMed

    Mu, Youbing; Wan, Xiaobo

    2016-03-01

    The strong adhesion ability of mussel foot-byssal proteins (Mfps) has inspired scientists to develop novel materials for strong and reversible adhesion, coating, antifouling, and many other applications. However, in many cases, the high costs and the tedious preparation steps of such bioinspired materials hamper the process to push them into practical application. Here a simple but effective way (one step) is presented to synthesize a mussel-inspired glue from two cheap commercially available materials: polyvinyl alcohol (PVA) and 3,4-dihydroxybenzaldehyde (DBA). This bioinspired hot curing adhesive exhibits a strong bonding ability as high as 17.3 MPa on stainless steel surfaces, which surpasses most of the commercially available adhesives.

  17. Ground-based Infrared Spectroscopy of the Extremely Hot Jupiter WASP-12b

    NASA Astrophysics Data System (ADS)

    Crossfield, Ian J. M.; Hansen, B.; Barman, T.

    2012-01-01

    Photometric characterization of transiting extrasolar planets leaves substantial degeneracies in atmospheric composition and structure, but properly calibrated spectroscopy can resolve these uncertainties and provide tighter constraints on atmospheric structure and abundances. Our team is observing transits and eclipses in the near-infrared to obtain spectra of a subset of transiting planets. I will present our tentative detection of the thermal emission spectrum of Hot Jupiter WASP-12b. We seem to confirm the 3,000 K near-infrared brightness temperature but our results are not precise enough to constrain individual molecular features. I will also present results from four transits of the low-mass planet GJ 1214b, which has been claimed to host a cloud-covered or non-H-dominated atmosphere.

  18. DEVELOPMENT OF A CALCIUM-BASED SORBENT FOR HOT GAS CLEANUP

    SciTech Connect

    T.D. Wheelock; L.K. Doraiswamy; K. Constant

    1999-03-31

    The preparation and testing of potential sorbents for removing H{sub 2}S and COS from hot coal gas continued. Two preparation methods received the most consideration. Both methods involve pelletizing powders in a revolving drum under moist conditions followed either by heat treatment or steam curing to harden the pellets, depending on the particle bonding mechanism. One method was used to pelletize mixtures of calcium carbonate and either alumina or a calcium aluminate cement in a single step. Another method was used to pelletize powdered limestone in an initial step followed by the application of a coating consisting of both limestone and a hydraulic cement in a second step. By employing this method, an especially promising material was produced consisting of a limestone core surrounded by a shell consisting initially of 80 wt.% limestone and 20% wt.% calcium aluminate cement. The best material exhibited both an acceptable crushing strength and adsorption capacity for H{sub 2}S.

  19. Thermoelectric Properties of Hot-Pressed Materials Based on Mg2Si n Sn1- n

    NASA Astrophysics Data System (ADS)

    Samunin, A. Yu.; Zaitsev, V. K.; Konstantinov, P. P.; Fedorov, M. I.; Isachenko, G. N.; Burkov, A. T.; Novikov, S. V.; Gurieva, E. A.

    2013-07-01

    Mg2Si n Sn1- n solid solutions consist of nontoxic widespread elements. In this work a number of samples of Mg2Si n Sn1- n solid solutions, where 1 ≥ n ≥ 0.7 with various carrier concentrations, were obtained using microcrystalline powder by hot pressing in vacuum. The Seebeck coefficient and the thermal and electrical conductivity were measured in the temperature range from 300 K to 800 K. It is shown that the specific thermoelectric figure of merit (the ratio of the thermoelectric figure of merit to the material density) of these samples weakly depends on the composition of the solid solution. Hence, whether a solid solution or pure Mg2Si is used depends on the application temperature of the material.

  20. Superplasticity and hot rolling of two-phase intermetallic alloy based on TiAl

    SciTech Connect

    Imayev, R.; Shagiev, M.; Salishchev, G.; Imayev, V.; Valitov, V.

    1996-03-15

    The recent investigations of superplasticity (SP) in intermetallic alloys indicate that these materials exhibit lower indices of SP (the relative elongation to rupture) at high enough homologous temperatures and low strain rates compared to conventional alloys. This behavior inhibits application of SP effects in intermetallics. The results of two-phase titanium alloys indicate that the combination of a high stable microstructure with a submicron grain size is necessary to realize the effect of SP at relatively high strain rates. The aim of the present work is to examine the SP behavior of a Ti-46at.%Al intermetallic alloy (TiAl + Ti{sub 3}Al) with micro- and submicron grain sizes and to apply obtained results in hot rolling.

  1. Attojoule energy resolution of direct detector based on hot electron bolometer

    NASA Astrophysics Data System (ADS)

    Seliverstov, S. V.; Rusova, A. A.; Kaurova, N. S.; Voronov, B. M.; Goltsman, G. N.

    2016-08-01

    We characterize superconducting antenna-coupled NbN hot-electron bolometer (HEB) for direct detection of THz radiation operating at a temperature of 9.0 K. At signal frequency of 2.5 THz, the measured value of the optical noise equivalent power is 2.0×10-13 W-Hz-0.5. The estimated value of the energy resolution is about 1.5 aJ. This value was confirmed in the experiment with pulsed 1.55-μm laser employed as a radiation source. The directly measured detector energy resolution is 2 aJ. The obtained risetime of pulses from the detector is 130 ps. This value was determined by the properties of the RF line. These characteristics make our detector a device-of-choice for a number of practical applications associated with detection of short THz pulses.

  2. Sub-wavelength quarter-wave plate based on plasmonic patch antennas

    NASA Astrophysics Data System (ADS)

    Zhao, Hang; Yang, Yuanqing; Li, Qiang; Qiu, Min

    2013-12-01

    A quarter-wave plate using plasmonic patch antennas has been investigated. The nanostructures can convert linear polarized light into circular polarized light in the visible range (633 nm). By further exploiting the dimer patch antenna structure composed of different metals, directional emission (with a directivity of 4.8) of circular polarized light (with a conversion efficiency of 27.8%) in an oblique direction with respect to the incident light is enabled. Compared with previous designs, the proposed structures are ultra-thin, and are more suitable for integration applications.

  3. Flat-plate solar-collector performance data base and user's manual

    NASA Astrophysics Data System (ADS)

    Kirkpatrick, D. L.; Kolar, W. A.

    1983-07-01

    The reader is provided with a thorough understanding on the type of collector thermal performance information which is required in active system design and analysis. Thermal performance test data on 109 commercially available solar collectors which were evaluated in a single, uniform test program, the Interim Solar Collector Test (ISCT) Program are given. In addition to recounting the ISCT program and its results, the an introduction is given on the engineering and physics of a flat-plate solar collector operation. A step-by-step analysis of heat gains and losses is provided to help the reader understand both the source and applicability of the parameters used to describe collector thermal performance. A brief description of the engineering basis for the ASHRAE Standard 93-77 test procedure and the method are included. To demonstrate the sensitivity to variations of collector performance parameters of the annual output of representative solar heating systems, three sets of F-Chart (4.0) system performance predictions are given. Finally, a sensitivity analysis study is presented which considers the heat loss and optical gain parameters of flat-plate collectors, in terms of how they affect the overall solar heating system solar fraction.

  4. Comparison of GD2 Binding Capture ELISA Assays for Anti-GD2-Antibodies Using GD2-Coated Plates and a GD2-Expressing Cell-Based ELISA

    PubMed Central

    Soman, Gopalan; Yang, Xiaoyi; Jiang, Hengguang; Giardina, Steve; Mitra, Gautam

    2011-01-01

    Two assay methods for quantification of the disialoganglioside (GD2)-specific binding activities of anti-GD2 monoclonal antibodies and antibody immunofusion proteins, such as ch14.18 and hu14.18-IL2, were developed. The methods differed in the use of either microtiter plates coated with purified GD2 or plates seeded with GD2-expressing cell lines to bind the anti-GD2 molecules. The bound antibodies were subsequently detected using the reactivity of the antibodies to an HRP-labeled anti-IgG Fc or antibodies recognizing the conjugate IL-2 part of the Hu 14.18IL-2 fusion protein. The bound HRP was detected using reagents such as orthophenylene diamine, 2, 2’-azinobis [3-ethylbenzothiazoline-6-sulfonic acid] or tetramethylbenzidine. The capture ELISA using GD2-coated plates was developed earlier in assay development and used to demonstrate assay specificity and to compare lot-to-lot consistency and stability of ch14.18, and Hu14.18 IL-2 in clinical development. During this study, we found a number of issues related to plate-to-plate variability, GD2 lot variability, and variations due to GD2 storage stability, etc., that frequently lead to assay failure in plates coated with purified GD2. The cell-based ELISA (CbELISA) using the GD2 expressing melanoma cell line, M21/P6, was developed as an alternative to the GD2-coated plate ELISA. The results on the comparability of the capture ELISA on GD2-coated plates and the cell-based assay show that both assays give comparable results. However, the cell-based assay is more consistent and reproducible. Subsequently, the anti-GD2 capture ELISA using the GD2-coated plate was replaced with the CbELISA for product lot release testing and stability assessment. PMID:21893062

  5. Hot compression deformation behavior and a modified physically-based constitutive model of Cu-6 %Ag alloy

    NASA Astrophysics Data System (ADS)

    Meng, Lie; Wang, Menghan; Liu, Xiao; Wang, Fenglin

    2016-04-01

    In order to reveal the flow characteristics of Cu-6 %Ag alloy on the condition of hot deformation, the isothermal compression experiments are carried out at the temperatures of 973-1123 K under strain rates of 0.01-10 s-1. The effects of deformation condition on the hot compression deformation behavior are investigated. The low instability strain (ɛ i) behavior at high strain rate (10 s-1) is discussed in this paper. According to the experiment results and analyses, the deformation twinning and inhomogeneous grains are thought to be the possible reasons for low strain cracking. Then, a modified physically based constitutive model is established. The strain for maximum softening rate (\\varepsilon_{ *} ) is quoted in the constitutive equation which is proved that there is a nearly linear relationship between { ln }\\varepsilon_{ *} and { ln }Z . What's more, the correlation coefficient (R) and the average absolute relative error (AARE) are used to evaluate the accuracy of the established constitutive model. The values of R and AARE are 0.99612 and 3.47 %, respectively, which show that the modified constitutive model can exactly reveal the flow stress of Cu-6 %Ag alloy.

  6. Photoproduct frequency is not the major determinant of UV base substitution hot spots or cold spots in human cells

    SciTech Connect

    Brash, D.E.; Seetharam, S.; Kraemer, K.H.; Seidman, M.M.; Bredberg, A.

    1987-06-01

    The role of UV radiation-induced photoproducts in initiating base substitution mutations in human cells was examined by measuring photoproduct frequency distributions and mutations in a supF tRNA gene on a shuttle vector plasmid transfected into DNA repair-deficient cells (xeroderma pigmentosum, complementation group A) and into normal cells. Frequencies of cyclobutane dimers and pyrimidine-pyrimidone (6-4) photoproducts varied by as much as 80-fold at different dipyrimidine sites within the gene. All transition mutations occurred at dipyrimidine sites, predominantly at cytosine, with a 17-fold variation in mutation frequency between different sites. Removal of greater than 99% of the cyclobutane dimers by in vitro photoreactivation before transfection reduced the mutation frequency while preserving the mutation distribution, indicating that (i) cytosine-containing cyclobutane dimers were the major mutagenic lesions at these sites and (ii) cytosine-containing non-cyclobutane dimer photoproducts were also mutagenic lesions. However, at individual dipyrimidine sites neither the frequency of cyclobutane dimers nor the frequency of pyrimidine-pyrimidone (6-4) photoproducts correlated with the mutation frequency, even in the absence of excision repair. Mutation hot spots occurred at sites with low or high frequency of photoproduct formation and mutation cold spots occurred at sites with many photoproducts. These results suggest that although photoproducts are required for UV mutagenesis, the prominence of most mutation hot spots and cold spots is primarily determined by DNA structural features rather than by the frequency of DNA photoproducts.

  7. Tidally distorted exoplanets: Density corrections for short-period hot-Jupiters based solely on observable parameters

    SciTech Connect

    Burton, J. R.; Watson, C. A.; Fitzsimmons, A.; Moulds, V.; Pollacco, D.; Wheatley, P. J.; Littlefair, S. P.

    2014-07-10

    The close proximity of short-period hot-Jupiters to their parent star means they are subject to extreme tidal forces. This has a profound effect on their structure and, as a result, density measurements that assume that the planet is spherical can be incorrect. We have simulated the tidally distorted surface for 34 known short-period hot-Jupiters, assuming surfaces of constant gravitational equipotential for the planet, and the resulting densities have been calculated based only on observed parameters of the exoplanet systems. Comparing these results to the density values, assuming the planets are spherical, shows that there is an appreciable change in the measured density for planets with very short periods (typically less than two days). For one of the shortest-period systems, WASP-19b, we determine a decrease in bulk density of 12% from the spherical case and, for the majority of systems in this study, this value is in the range of 1%-5%. On the other hand, we also find cases where the distortion is negligible (relative to the measurement errors on the planetary parameters) even in the cases of some very short period systems, depending on the mass ratio and planetary radius. For high-density gas planets requiring apparently anomalously large core masses, density corrections due to tidal deformation could become important for the shortest-period systems.

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

    SciTech Connect

    Abrutis, Adulfas Silimavicus, Laimis; Kubilius, Virgaudas; Murauskas, Tomas; Saltyte, Zita; Kuprenaite, Sabina; Plausinaitiene, Valentina

    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.

  9. Defect Prediction and Control for Ultra-high-strength Steel Complex Structure in Hot Forming Based on FEM

    NASA Astrophysics Data System (ADS)

    Shang, Xin; Zhou, Jie; Zhuo, Fang; Luo, Yan; Li, Yang

    2015-06-01

    Cracking is the main defect in ultra-high-strength steel (UHSS) forming products. In order to avoid cracking, either adjusting process parameters or changing die's design is usually applied. However, under the condition of forming parts with unreasonable structure design, it makes little difference through the traditional methods of modifying process parameters. In this paper, true stress-strain curves under different strain rates and temperatures are obtained via the hot tensile tests. Then, the material constitutive model of UHSS is introduced into software CAE; this step is used to analyze and predict defects of UHSS hot forming complex structural parts based on FEM. In addition, simulation results of changed structure (open end) are compared with original structure (closed end). The results have shown that both maximum reduction ratio and stress in all directions are sharply reduced, i.e., the forming quality is improved significantly after changing the end structure. Finally, the prediction and control methods of forming defects are verified to be feasible in actual production.

  10. Liquid extraction surface analysis (LESA) of hydrophobic TLC plates coupled to chip-based nanoelectrospray high-resolution mass spectrometry.

    PubMed

    Himmelsbach, Markus; Varesio, Emmanuel; Hopfgartner, Gérard

    2014-01-01

    Direct identification and structural characterization of analyte spots on TLC plates have always been of great interest and the development of interfaces that allow TLC to be combined with MS is making steady progress. The recently introduced liquid extraction surface analysis (LESA) approach has the potential to hyphenate TLC with MS. A mixture of lipid standards was separated on HPTLC RP-18 glass plates using chloroform:methanol :acetonitrile 2:1:1 (v:v:v) as mobile phase. After visualization with primuline dye (0.02% in acetone:water 8:2 (v:v)), LESA was performed, followed by a chip-based nanoflow infusion in combination with FTICRMS. The optimized extraction solvent composition was methanol:chloroform:water:formic acid 52:24:24:0.2 (v:v:v:v). A nanoelectrospray voltage of 1.6 kV and a gas pressure of 0.2 psi were applied in all experiments. All phospholipids were extracted successfully and detected unambiguously using the optimized TLC-LESA-FTICRMS procedure. Sampling the tricaprylin spot gave the most intense signals and also tricaprin was detected. Three other triacylglycerols of higher molecular mass have logP values between 15.5 and 21.6, which are the highest among all investigated compounds and are not detected from their corresponding spots, due to the fact that the solubility of very apolar lipids is not high enough in the extraction solvent. It was demonstrated that TLC can be elegantly combined with mass spectrometry based on the LESA approach. In general, apart from the analysis of lipids, TLC-LESA-MS has a high potential for medium-polar compounds separated on reversed-phase TLC plates, but limitations are present when very apolar compounds have to be extracted.

  11. Peen plating

    NASA Technical Reports Server (NTRS)

    Babecki, A. J. (Inventor); Haehner, C. L.

    1973-01-01

    A process for metal plating which comprises spraying a mixture of metallic powder and small peening particles at high velocity against a surface is described. The velocity must be sufficient to impact and bond metallic powder onto the surface. In the case of metal surfaces, the process has as one of its advantages providing mechanical working (hardening) of the surface simultaneously with the metal plating.

  12. Fluorescence microscopy imaging with a Fresnel zone plate array based optofluidic microscope

    PubMed Central

    Han, Chao; Lee, Lap Man; Yang, Changhuei

    2013-01-01

    We report the implementation of an on-chip microscope system, termed fluorescence optofluidic microscope (FOFM), which is capable of fluorescence microscopy imaging of samples in fluid media. The FOFM employs an array of Fresnel zone plates (FZP) to generate an array of focused light spots within a microfluidic channel. As a sample flows through the channel and across the array of focused light spots, the fluorescence emissions are collected by a filter-coated CMOS sensor, which serves as the channel's floor. The collected data can then be processed to render fluorescence microscopy images at a resolution determined by the focused light spot size (experimentally measured as 0.65 μm FWHM). In our experiments, our established resolution was 1.0 μm due to Nyquist criterion consideration. As a demonstration, we show that such a system can be used to image the cell nuclei stained by Acridine Orange and cytoplasm labeled by Qtracker®. PMID:21935556

  13. Development of TOF-PET detectors based on the Multi-Gap Resistive Plate Chambers

    NASA Astrophysics Data System (ADS)

    Amaldi, U.; Borghi, G.; Bucciantonio, M.; Kieffer, R.; Samarati, J.; Sauli, F.; Watts, D.

    2015-04-01

    We describe the development, construction and preliminary results obtained with medium-size Multi-Gap Resistive Plate Chambers prototypes designed to detect and localize 511 keV photons for Positron Emission Tomography imaging applications. The devices are intended for in-beam monitoring of the treatment plans throughout deep tumor therapy with hadron beams; emphasis is put on achieving coincidence time resolutions of few hundred ps, in order to exploit optimized reconstruction algorithm and reduce the heavy non-correlated background contributions distinctive of this operation. Using technologies developed for high energy physics experiments, the detectors can be built for covering large areas, thus leading the way to the conception of full-body PET systems at low cost.

  14. Generation of cylindrical vector beams based on common-path interferometer with a vortex phase plate

    NASA Astrophysics Data System (ADS)

    Liang, Yansheng; Yan, Shaohui; Yao, Baoli; Lei, Ming; Min, Junwei; Yu, Xianghua

    2016-04-01

    Cylindrical vector (CV) beams have found increasing applications in physics, biology, and chemistry. To generate CV beams, interferometric technique is popularly adopted due to its flexibility. However, most interferometric configurations for the generation of CV beams are faced with system instability arising from external disturbance, limiting their practical applications. A common-path interferometer for the generation of radially and azimuthally polarized beams is proposed to improve the system stability. The optical configuration consists of a vortex phase plate acting to tailor the phase profile and a cube nonpolarizing beamsplitter to split the input beam into two components with mirror-like spiral phase distribution. The generated CV beams show a high quality in polarization and exhibit a better stability of beam profile than those obtained by noncommon-path interferometric configurations.

  15. Common-path on-axis Fresnel holography based on a pinhole array plate.

    PubMed

    Zhang, Xin-Ting; Guo, Cheng-Shan

    2015-01-01

    A common-path and on-axis configuration for improving the resolution power of a lensless Fresnel holographic imaging system is proposed. In this configuration, a pinhole array plate (PAP) is inserted between the object and the recording plane. We demonstrated that the complex amplitude of the object wave can be directly extracted from a single Fresnel hologram of the object wave sampled by the PAP, and the numerical aperture of the effective imaging system can be increased because of the diffraction effect of the pinhole array. It may provide one approach for improving the capabilities of digital holography available for a wide range of wavelengths from far-infrared to x-ray and electron beams.

  16. Matrix based system of isotretinoin as nail lacquer to enhance transungal delivery across human nail plate.

    PubMed

    Joshi, Monika; Sharma, Vijay; Pathak, Kamla

    2015-01-15

    The project was aimed at development of isotretinoin nail lacquer and assessment of its penetration efficiency across human nail plate. Preliminary studies (hydration enhancement factor and SEM) aided the selection of thioglycolic acid as permeation and eugenol was selected as local anesthetic in the formulation. The nail lacquer was optimized by 3(2) factorial design and a total of nine formulations were prepared and screened. In vitro adhesion and ex vivo permeation (cumulative drug permeation per unit area (CDP/A) = 6.61 ± 0.57 mg/cm(2)) across bovine hoof guided the selection of F3 as optimized formulation that was improvised. Viscosity adjustments to improve handling characteristics were affected by incorporation of ethyl cellulose (6%; F3M1) that scaled the viscosity to 312.681 cp and insignificantly (p > 0.05) affected CDP/A (6.32 ± 0.45 mg/cm(2)). In comparison to marketed preparation (Retino-A cream) F3M1 afforded two fold increase in CDP/A. The permeation characteristics were defined by Higuchi model (r(2) = 0.964) and flux value of 176 μg/cm(2)/h. Confocal laser scanning microscopy, after 72 h of nail lacquer application, revealed extensive distribution of the fluorescent tracer across the human nail plate in comparison to control that was confined to the top layer. Conclusively, an efficacious and stable nail lacquer of isotretinoin was developed for potential clinical topical use to target the drug to nail bed in treatment of nail psoriasis.

  17. Astrometry of the h and χ Persei clusters based on the processing of digitized photographic plates

    NASA Astrophysics Data System (ADS)

    Muminov, Muydin; Yuldoshev, Qudrat; Ehgamberdiev, Shukhrat; Kahharov, Bakhtiyor; Relke, Helena; Protsyuk, Yury; Pakuliak, Ludmila; Andruk, Vitaly

    2017-01-01

    The work was carried out to ascertain the possibility of using the scanner Epson Expression 10000XL of Astronomical Institute Academy of Sciences of Uzbekistan for any astrometric and photometric works. Photographic plates were obtained with the normal astrograph of Astronomical Institute (D/F = 330mm/3467mm, M = 59.56 "/mm). The digitizing of photographic plates with linear dimensions 16 x 16 cm was made with a spatial resolution of 1200 dpi (1px = 1.25"). For this study the images of the first (1935.0) and second (1976.9 ) epochs were used in the sky area of 4 sq. degrees with the χ and h Persei open clusters. Positions and B-magnitudes of the stars were obtained in the system of the TYCHO2 reference catalogue. The errors of differences in the positions and proper motions for the 655 reference stars used for the astrometric reduction are σ_{αδ} = ± 0.0.074" and σ_{μαδ} = ± 0.0018"/year respectively. The internal photometric errors σ_m are ±0.065^m. The comparison of the determined B-magnitudes with the B-magnitudes of the TYCHO2 gave the error values of σ_B = ±0.208^m. The comparison of 8123 common stars down to B ≤ 17.5^m with UCAC4 gave the error values of σ_{αδ} = ±0.28", σ_{μαδ} = ±0.0075"/year and σ_m = ±0.139^m for positions, proper motions and stellar magnitudes respectively.

  18. Hot corrosion behavior of Ni based Inconel 617 and Inconel 738 superalloys

    NASA Astrophysics Data System (ADS)

    El-Awadi, G. A.; Abdel-Samad, S.; Elshazly, Ezzat S.

    2016-08-01

    Superalloys are extensively used at high temperature applications due to their good oxidation and corrosion resistance properties in addition to their high stability were made at high temperature. Experimental measurements of hot corrosion at high temperature of Inconel 617 and Inconel 738 superalloys. The experiments were carried out at temperatures 700 °C, 800 °C and 900 °C for different exposure times to up to 100 h. The corrosive media was NaCl and Na2SO4 sprayed on the specimens. Seven different specimens were used at each temperature. The corrosion process is endothermic and the spontaneity increased by increasing temperature. The activation energy was found to be Ea = 23.54 and Ea = 25.18 KJ/mol for Inconel 738 and Inconel 617 respectively. X-ray diffraction technique (XRD) was used to analyze the formed scale. The morphology of the specimen and scale were examined by scanning electron microscopy (SEM). The results show that the major corrosion products formed were NiCr2O4, and Co Cr2O4 spinles, in addition to Cr2O3.

  19. Study of timing response and charge spectra of glass based Resistive Plate Chamber detectors for INO-ICAL experiment

    NASA Astrophysics Data System (ADS)

    Gaur, A.; Kumar, A.; Naimuddin, Md.

    2017-03-01

    Resistive Plate chambers (RPCs) are robust and affordable gaseous detectors that combine low cost with excellent timing, good spatial resolution and fast response to the incoming particles. The India Based Neutrino Observatory is an approved project aimed at building a magnetised Iron Calorimeter (ICAL) detector to study Neutrino physics and related issues. The ICAL experiment will utilize about 29000 RPC's as active detector elements, sandwiched between alternate plates of thick iron. The RPC detectors will be used to detect muons produced from the atmospheric neutrinos interaction with an iron target. The spatial information of the muons will be extracted from the two dimensional readout and the hit position in the respective layers. The up going and down going directionality will be obtained using the time stamp of hits in the active detectors. The charge induced by the particle and its behaviour with respect to the applied voltage play a significant role in designing the readout electronics for the detector. In this paper, we present the timing and charge measurement of single gap glass based RPC detectors. We will also report about studies on the dependence of the timing and charge response of these RPC detectors as a function of the gas composition.

  20. Scalable 96-well Plate Based iPSC Culture and Production Using a Robotic Liquid Handling System.

    PubMed

    Conway, Michael K; Gerger, Michael J; Balay, Erin E; O'Connell, Rachel; Hanson, Seth; Daily, Neil J; Wakatsuki, Tetsuro

    2015-05-14

    Continued advancement in pluripotent stem cell culture is closing the gap between bench and bedside for using these cells in regenerative medicine, drug discovery and safety testing. In order to produce stem cell derived biopharmaceutics and cells for tissue engineering and transplantation, a cost-effective cell-manufacturing technology is essential. Maintenance of pluripotency and stable performance of cells in downstream applications (e.g., cell differentiation) over time is paramount to large scale cell production. Yet that can be difficult to achieve especially if cells are cultured manually where the operator can introduce significant variability as well as be prohibitively expensive to scale-up. To enable high-throughput, large-scale stem cell production and remove operator influence novel stem cell culture protocols using a bench-top multi-channel liquid handling robot were developed that require minimal technician involvement or experience. With these protocols human induced pluripotent stem cells (iPSCs) were cultured in feeder-free conditions directly from a frozen stock and maintained in 96-well plates. Depending on cell line and desired scale-up rate, the operator can easily determine when to passage based on a series of images showing the optimal colony densities for splitting. Then the necessary reagents are prepared to perform a colony split to new plates without a centrifugation step. After 20 passages (~3 months), two iPSC lines maintained stable karyotypes, expressed stem cell markers, and differentiated into cardiomyocytes with high efficiency. The system can perform subsequent high-throughput screening of new differentiation protocols or genetic manipulation designed for 96-well plates. This technology will reduce the labor and technical burden to produce large numbers of identical stem cells for a myriad of applications.

  1. Scalable 96-well Plate Based iPSC Culture and Production Using a Robotic Liquid Handling System

    PubMed Central

    Conway, Michael K.; Gerger, Michael J.; Balay, Erin E.; O'Connell, Rachel; Hanson, Seth; Daily, Neil J.; Wakatsuki, Tetsuro

    2015-01-01

    Continued advancement in pluripotent stem cell culture is closing the gap between bench and bedside for using these cells in regenerative medicine, drug discovery and safety testing. In order to produce stem cell derived biopharmaceutics and cells for tissue engineering and transplantation, a cost-effective cell-manufacturing technology is essential. Maintenance of pluripotency and stable performance of cells in downstream applications (e.g., cell differentiation) over time is paramount to large scale cell production. Yet that can be difficult to achieve especially if cells are cultured manually where the operator can introduce significant variability as well as be prohibitively expensive to scale-up. To enable high-throughput, large-scale stem cell production and remove operator influence novel stem cell culture protocols using a bench-top multi-channel liquid handling robot were developed that require minimal technician involvement or experience. With these protocols human induced pluripotent stem cells (iPSCs) were cultured in feeder-free conditions directly from a frozen stock and maintained in 96-well plates. Depending on cell line and desired scale-up rate, the operator can easily determine when to passage based on a series of images showing the optimal colony densities for splitting. Then the necessary reagents are prepared to perform a colony split to new plates without a centrifugation step. After 20 passages (~3 months), two iPSC lines maintained stable karyotypes, expressed stem cell markers, and differentiated into cardiomyocytes with high efficiency. The system can perform subsequent high-throughput screening of new differentiation protocols or genetic manipulation designed for 96-well plates. This technology will reduce the labor and technical burden to produce large numbers of identical stem cells for a myriad of applications. PMID:26068617

  2. Hot Tickets

    ERIC Educational Resources Information Center

    Fox, Bette-Lee; Hoffert, Barbara; Kuzyk, Raya; McCormack, Heather; Williams, Wilda

    2008-01-01

    This article describes the highlights of this year's BookExpo America (BEA) held at the Los Angeles Convention Center. The attendees at BEA had not minded that the air was recycled, the lighting was fluorescent, and the food was bad. The first hot book sighting came courtesy of Anne Rice. Michelle Moran, author of newly published novel, "The…

  3. Hot Canyon

    ScienceCinema

    None

    2016-07-12

    This historical film footage, originally produced in the early 1950s as part of a series by WOI-TV, shows atomic research at Ames Laboratory. The work was conducted in a special area of the Laboratory known as the "Hot Canyon."

  4. Hot Canyon

    SciTech Connect

    2012-01-01

    This historical film footage, originally produced in the early 1950s as part of a series by WOI-TV, shows atomic research at Ames Laboratory. The work was conducted in a special area of the Laboratory known as the "Hot Canyon."

  5. Configurable hot spot fixing system

    NASA Astrophysics Data System (ADS)

    Kajiwara, Masanari; Kobayashi, Sachiko; Mashita, Hiromitsu; Aburada, Ryota; Furuta, Nozomu; Kotani, Toshiya

    2014-03-01

    Hot spot fixing (HSF) method has been used to fix many hot spots automatically. However, conventional HSF based on a biasing based modification is difficult to fix many hot spots under a low-k1 lithography condition. In this paper we proposed a new HSF, called configurable hotspot fixing system. The HSF has two major concepts. One is a new function to utilize vacant space around a hot spot by adding new patterns or extending line end edges around the hot spot. The other is to evaluate many candidates at a time generated by the new functions. We confirmed the proposed HSF improves 73% on the number of fixing hot spots and reduces total fixing time by 50% on a device layout equivalent to 28nm-node. The result shows the proposed HSF is effective for layouts under the low-k1 lithography condition.

  6. Ultrasensitive SERS detection of trinitrotoluene through capillarity-constructed reversible hot spots based on ZnO-Ag nanorod hybrids

    NASA Astrophysics Data System (ADS)

    He, Xuan; Wang, Hui; Li, Zhongbo; Chen, Dong; Liu, Jiahui; Zhang, Qi

    2015-04-01

    A simple and efficient self-approach strategy was used to apply ultrasensitivity and self-revive ZnO-Ag hybrid surface-enhanced Raman scattering (SERS) sensors for the highly sensitive and selective detection of explosive TNT in both solution and vapour conditions. The good ultrasensitive sensing performance is a result of the abundant Raman hot spots, which were spontaneously formed in a reversible way by the self-approaching of flexible ZnO-Ag hybrid nanorods driven by the capillary force of solvent evaporation. Moreover, the enhancement effect was repeatedly renewed by the reconstruction of molecular bridges, which could selectively detect TNT with a lower limit of 4 × 10-14 M. In addition, TNT vapor was also tested under this sensor, whereby once the ZnO-Ag NRs hybrid substrate was dipped in TNT, this substrate could detect the existence of TNT even in 5 detection cycles via a capillarity-constructed reversible hot spots approach. Compared with other pure Ag-based SERS sensors, this ZnO-Ag hybrid SERS sensor could rapidly self-revive SERS-activity by simple UV light irradiation and could retain stable SERS sensitivity for one month when used for TNT detection. This stable and ultrasensitive SERS substrate demonstrates a new route to eliminate the oxidized inactive problem of traditional Ag-based SERS substrates and suggests promising use in the applications of such hybrids as real-time online sensors for explosives detection.A simple and efficient self-approach strategy was used to apply ultrasensitivity and self-revive ZnO-Ag hybrid surface-enhanced Raman scattering (SERS) sensors for the highly sensitive and selective detection of explosive TNT in both solution and vapour conditions. The good ultrasensitive sensing performance is a result of the abundant Raman hot spots, which were spontaneously formed in a reversible way by the self-approaching of flexible ZnO-Ag hybrid nanorods driven by the capillary force of solvent evaporation. Moreover, the enhancement

  7. Effects of silicon on the oxidation, hot-corrosion, and mechanical behavior of two cast nickel-base superalloys

    NASA Technical Reports Server (NTRS)

    Miner, R. V., Jr.

    1977-01-01

    Cast specimens of nickel-base superalloys 713C and Mar-M200 with nominal additions of 0, 0.5, and 1 wt% Si were evaluated for oxidation and corrosion resistance, tensile and stress-rupture properties, microstructure, and phase relations. Results are compared with those of an earlier study of the effects of Si in B-1900. Si had similar effects on all three superalloys. It improves oxidation resistance but the improvement in 713C and Mar-M200 was considerably less than in B-1900. Hot-corrosion resistance is also improved somewhat. Si is, however, detrimental to mechanical properties, in particular, rupture strength and tensile ductility. Si has two obvious microstructural effects. It increases the amount of gamma-prime precipitated in eutectic nodules and promotes a Mo(Ni,Si)2 Laves phase in the alloys containing Mo. These microstructural effects do not appear responsible for the degradation of mechanical properties, however.

  8. NEAR-INFRARED THERMAL EMISSION DETECTIONS OF A NUMBER OF HOT JUPITERS AND THE SYSTEMATICS OF GROUND-BASED NEAR-INFRARED PHOTOMETRY

    SciTech Connect

    Croll, Bryce; Albert, Loic; Lafreniere, David; Jayawardhana, Ray; Cushing, Michael; Moutou, Claire; Johnson, John Asher; Bonomo, Aldo S.; Deleuil, Magali; Fortney, Jonathan

    2015-03-20

    We present detections of the near-infrared thermal emission of three hot Jupiters and one brown dwarf using the Wide-field Infrared Camera (WIRCam) on the Canada-France-Hawaii Telescope (CFHT). These include Ks-band secondary eclipse detections of the hot Jupiters WASP-3b and Qatar-1b and the brown dwarf KELT-1b. We also report Y-band, K {sub CONT}-band, and two new and one reanalyzed Ks-band detections of the thermal emission of the hot Jupiter WASP-12b. We present a new reduction pipeline for CFHT/WIRCam data, which is optimized for high precision photometry. We also describe novel techniques for constraining systematic errors in ground-based near-infrared photometry, so as to return reliable secondary eclipse depths and uncertainties. We discuss the noise properties of our ground-based photometry for wavelengths spanning the near-infrared (the YJHK bands), for faint and bright stars, and for the same object on several occasions. For the hot Jupiters WASP-3b and WASP-12b we demonstrate the repeatability of our eclipse depth measurements in the Ks band; we therefore place stringent limits on the systematics of ground-based, near-infrared photometry, and also rule out violent weather changes in the deep, high pressure atmospheres of these two hot Jupiters at the epochs of our observations.

  9. Elastomer based composite materials for bipolar plates in polymer electrolyte membrane fuel cells

    NASA Astrophysics Data System (ADS)

    Petrach, Elaine M.

    2011-07-01

    In most investigations, polymer conductive composite bipolar plates have failed to achieve the low resistivity required for PEMFCs. The goal of this dissertation is to investigate whether a composite of conductive fillers and a two-phase polymeric matrix will achieve low resistivity through preferred distribution of the fillers at the interface of the two phases. The use of an elastomer as one component of the blend will impart fracture resistance. Three types of matrices were investigated, a single phase polyvinyl ester plastic matrix, a compatible one-phase blend of polyvinyl ester (VER) and polyurethane (PU) elastomer, and a two-phase system of polyvinyl ester and ethylene propylene diene monomer (EPDM) elastomer. The different phases were determined by the theory of mixing. When solubility parameters are closer together it is likely that the system will be one phase. The one and two-phase systems were analyzed within the composition containing natural Cytec DKD graphite fibers, Asbury synthetic graphite 4012 flakes and ultra high surface area synthetic graphite TC 307. Phase systems affect the mechanical, electrical, and thermal properties. The percolation theory analysis was applied to determine the optimal percentage of conductive fillers and polymer blends. The optimal composition for composite materials consisted of 35vo1% of conductive fillers and 65vo1% of a two-phase blend matrix. The conductive filler included 3vol% of synthetic graphite TC307, 25.5vol% of Cytec DKD graphite fibers and 6.5vol% of Asbury synthetic graphite 4012 flakes. The two-phase blend matrix included 40vol% of EPDM to 60vol% of VER. This resulted in an electrical resistivity of 0.009O-cm and a thermal conductivity of 11.6W/m-K. The two-phase blend matrix added more ductility to the composition with the ability to withstand a stress of 10MPa with over 1% strain applied to the overall composite bipolar plates. The composition also absorbed 60% more mechanical energy than that

  10. Development of Microelectrode Arrays Using Electroless Plating for CMOS-Based Direct Counting of Bacterial and HeLa Cells.

    PubMed

    Niitsu, Kiichi; Ota, Shoko; Gamo, Kohei; Kondo, Hiroki; Hori, Masaru; Nakazato, Kazuo

    2015-10-01

    The development of two new types of high-density, electroless plated microelectrode arrays for CMOS-based high-sensitivity direct bacteria and HeLa cell counting are presented. For emerging high-sensitivity direct pathogen counting, two technical challenges must be addressed. One is the formation of a bacteria-sized microelectrode, and the other is the development of a high-sensitivity and high-speed amperometry circuit. The requirement for microelectrode formation is that the gold microelectrodes are required to be as small as the target cell. By improving a self-aligned electroless plating technique, the dimensions of the microelectrodes on a CMOS sensor chip in this work were successfully reduced to 1.2 μm × 2.05 μm. This is 1/20th of the smallest size reported in the literature. Since a bacteria-sized microelectrode has a severe limitation on the current flow, the amperometry circuit has to have a high sensitivity and high speed with low noise. In this work, a current buffer was inserted to mitigate the potential fluctuation. Three test chips were fabricated using a 0.6- μm CMOS process: two with 1.2 μm × 2.05 μm (1024 × 1024 and 4 × 4) sensor arrays and one with 6- μm square (16 × 16) sensor arrays; and the microelectrodes were formed on them using electroless plating. The uniformity among the 1024 × 1024 electrodes arranged with a pitch of 3.6 μm × 4.45 μm was optically verified. For improving sensitivity, the trenches on each microelectrode were developed and verified optically and electrochemically for the first time. Higher sensitivity can be achieved by introducing a trench structure than by using a conventional microelectrode formed by contact photolithography. Cyclic voltammetry (CV) measurements obtained using the 1.2 μm × 2.05 μm 4 × 4 and 6- μm square 16 × 16 sensor array with electroless-plated microelectrodes successfully demonstrated direct counting of the bacteria-sized microbeads and HeLa cells.

  11. Development of a New Fast Shower Maximum Detector Based on Microchannel Plates Photomultipliers (MCP-PMT) as an Active Element

    SciTech Connect

    Ronzhin, A.; Los, S.; Ramberg, E.; Spiropulu, M.; Apresyan, A.; Xie, S.; Kim, H.; Zatserklyaniy, A.

    2014-09-21

    One possibility to make a fast and radiation resistant shower maximum (SM) detector is to use a secondary emitter as an active element. We present below test beam results, obtained with different types of photodetectors based on microchannel plates (MCPs) as the secondary emitter. We performed the measurements at the Fermilab Test Beam Facility with 120GeV proton beam and 12GeV and 32GeV secondary beams. The goal of the measurement with 120GeV protons was to determine time resolution for minimum ionizing particles (MIPs). The SM time resolution we obtained for this new type of detector is at the level of 20-30ps. We estimate that a significant contribution to the detector response originates from secondary emission of the MCP. This work can be considered as the first step in building a new type of calorimeter based on this principle.

  12. Fatigue strength of Al7075 notched plates based on the local SED averaged over a control volume

    NASA Astrophysics Data System (ADS)

    Berto, Filippo; Lazzarin, Paolo

    2014-01-01

    When pointed V-notches weaken structural components, local stresses are singular and their intensities are expressed in terms of the notch stress intensity factors (NSIFs). These parameters have been widely used for fatigue assessments of welded structures under high cycle fatigue and sharp notches in plates made of brittle materials subjected to static loading. Fine meshes are required to capture the asymptotic stress distributions ahead of the notch tip and evaluate the relevant NSIFs. On the other hand, when the aim is to determine the local Strain Energy Density (SED) averaged in a control volume embracing the point of stress singularity, refined meshes are, not at all, necessary. The SED can be evaluated from nodal displacements and regular coarse meshes provide accurate values for the averaged local SED. In the present contribution, the link between the SED and the NSIFs is discussed by considering some typical welded joints and sharp V-notches. The procedure based on the SED has been also proofed to be useful for determining theoretical stress concentration factors of blunt notches and holes. In the second part of this work an application of the strain energy density to the fatigue assessment of Al7075 notched plates is presented. The experimental data are taken from the recent literature and refer to notched specimens subjected to different shot peening treatments aimed to increase the notch fatigue strength with respect to the parent material.

  13. Rapid determination of trace copper in animal feed based on micro-plate colorimetric reaction and statistical partitioning correction.

    PubMed

    Niu, Yiming; Wang, Jiayi; Zhang, Chi; Chen, Yiqiang

    2017-04-15

    The objective of this study was to develop a micro-plate based colorimetric assay for rapid and high-throughput detection of copper in animal feed. Copper ion in animal feed was extracted by trichloroacetic acid solution and reduced to cuprous ion by hydroxylamine. The cuprous ion can chelate with 2,2'-bicinchoninic acid to form a Cu-BCA complex which was detected with high sensitivity by micro-plate reader at 354nm. The whole assay procedure can be completed within 20min. To eliminate matrix interference, a statistical partitioning correction approach was proposed, which makes the detection of copper in complex samples possible. The limit of detection was 0.035μg/mL and the detection range was 0.1-10μg/mL of copper in buffer solution. Actual sample analysis indicated that this colorimetric assay produced results consistent with atomic absorption spectrometry analysis. These results demonstrated that the developed assay can be used for rapid determination of copper in animal feed.

  14. Behaviour of plate elements based on the first-order shear deformation theory

    NASA Technical Reports Server (NTRS)

    Averill, R. C.; Reddy, J. N.

    1990-01-01

    A new analytical technique to assess the performance of shear deformable elements is presented, which makes it possible to determine a priori whether a given element will lock when used to model thin structures. The role that shear constraints play in determining the behavior of thin elements was established by comparing the results of key numerical tests with the predictions of element behavior made by studying the form of the shear constraints. Conclusions regarding locking behavior and the effects of reduced integration in thin shear deformable elements are presented, including the findings (1) that singularity of the shear stiffness matrix is not sufficient to avoid locking; (2) that the effect of mesh refinement on an element that contains spurious constraints is two-fold; and (3) that reduced integration does not remove spurious constraints but rather relaxes them. The results of the study are in agreement with previous studies of Mindlin plate elements in regarding Lagrangian elements as superior to serendipity elements when either full or reduced integration is employed.

  15. Image-based fluidic sorting system for automated Zebrafish egg sorting into multiwell plates.

    PubMed

    Graf, Siegfried F; Hötzel, Sebastian; Liebel, Urban; Stemmer, Andreas; Knapp, Helmut F

    2011-04-01

    The global demand for the reduction of animal testing has led to the emergence of Zebrafish eggs/larvae as model organisms to replace current adult animal testing in, for example, toxicity testing. Because of the egg size (diameter 1.6mm) and the relatively easy maintenance of Zebrafish farms the eggs also offer high-throughput screening (HTS). However, the current bottleneck for HTS is the cost-efficient placing of individual organisms into single wells of a multiwell plate (MWP). The system presented here is capable of storing, sorting, and placing individual organisms in a highly reproducible manner. In about 11 min a complete 96-MWP is filled, which corresponds to about 8 sec per egg. The survival rate of fertilized transgenic and wild-type eggs was comparable to the one of the control (control 6.7%, system 7.6%). Furthermore, it was also possible to place dechorionated eggs into individual wells. The results demonstrate that the cost efficient system works gentle and reliable enough to disburden scientists from the exhausting and monotonous job of placing single eggs into single wells, such that they can concentrate on the scientific aspects of their experiments and create results with a higher statistical relevance.

  16. Optically switchable and axially symmetric half-wave plate based on photoaligned liquid crystal films

    NASA Astrophysics Data System (ADS)

    Lin, C.-C.; Huang, T.-C.; Chu, C.-C.; Hsiao, Vincent K. S.

    2016-07-01

    We demonstrate an optically switchable half-wave plate (HWP) composed of a photoaligned and axially symmetric liquid crystal (ASLC) film containing two azobenzene derivatives, methyl red (MR) and 4-butyl-4‧-methoxyazobenzene (BMAB). MR is responsible for photoalignment, and BMAB is used for optical tuning and switching the state of polarization (SOP) of probe beam (633 nm He-Ne laser) passing through the MR/BMAB doped ASLC film. The photoaligned ASLC film is first fabricated using a line-shaped laser beam (532 nm) exposure applied on a rotating LC sample. The fabricated ASLC film can passively change the linearly polarized light. Under UV light exposure, the formation of cis-BMAB (bend-like shape) within the film disrupts the LC molecules, switches the LC orientation, and further changes the SOP of the probe beam. Under laser irradiation (532 nm), the formation of trans-BMAB (rod-like shape) reverts the LC orientation back and simultaneously generates cis-MR, helping anchor the LC in the previously photoaligned orientation. The photoaligned MR/BMAB-doped LC HWP can change the linear SOP under alternating UV and visible light exposure.

  17. Deformation and fracture of explosion-welded Ti/Al plates: A synchrotron-based study

    DOE PAGES

    E, J. C.; Huang, J. Y.; Bie, B. X.; ...

    2016-08-02

    Here, explosion-welded Ti/Al plates are characterized with energy dispersive spectroscopy and x-ray computed tomography, and exhibit smooth, well-jointed, interface. We perform dynamic and quasi-static uniaxial tension experiments on Ti/Al with the loading direction either perpendicular or parallel to the Ti/Al interface, using a mini split Hopkinson tension bar and a material testing system in conjunction with time-resolved synchrotron x-ray imaging. X-ray imaging and strain-field mapping reveal different deformation mechanisms responsible for anisotropic bulk-scale responses, including yield strength, ductility and rate sensitivity. Deformation and fracture are achieved predominantly in Al layer for perpendicular loading, but both Ti and Al layers asmore » well as the interface play a role for parallel loading. The rate sensitivity of Ti/Al follows those of the constituent metals. For perpendicular loading, single deformation band develops in Al layer under quasi-static loading, while multiple deformation bands nucleate simultaneously under dynamic loading, leading to a higher dynamic fracture strain. For parallel loading, the interface impedes the growth of deformation and results in increased ductility of Ti/Al under quasi-static loading, while interface fracture occurs under dynamic loading due to the disparity in Poisson's contraction.« less

  18. Deformation and fracture of explosion-welded Ti/Al plates: A synchrotron-based study

    SciTech Connect

    E, J. C.; Huang, J. Y.; Bie, B. X.; Sun, T.; Fezzaa, K.; Xiao, X. H.; Sun, W.; Luo, S. N.

    2016-08-02

    Here, explosion-welded Ti/Al plates are characterized with energy dispersive spectroscopy and x-ray computed tomography, and exhibit smooth, well-jointed, interface. We perform dynamic and quasi-static uniaxial tension experiments on Ti/Al with the loading direction either perpendicular or parallel to the Ti/Al interface, using a mini split Hopkinson tension bar and a material testing system in conjunction with time-resolved synchrotron x-ray imaging. X-ray imaging and strain-field mapping reveal different deformation mechanisms responsible for anisotropic bulk-scale responses, including yield strength, ductility and rate sensitivity. Deformation and fracture are achieved predominantly in Al layer for perpendicular loading, but both Ti and Al layers as well as the interface play a role for parallel loading. The rate sensitivity of Ti/Al follows those of the constituent metals. For perpendicular loading, single deformation band develops in Al layer under quasi-static loading, while multiple deformation bands nucleate simultaneously under dynamic loading, leading to a higher dynamic fracture strain. For parallel loading, the interface impedes the growth of deformation and results in increased ductility of Ti/Al under quasi-static loading, while interface fracture occurs under dynamic loading due to the disparity in Poisson's contraction.

  19. Effect of hot implantation on ON-current enhancement utilizing isoelectronic trap in Si-based tunnel field-effect transistors

    NASA Astrophysics Data System (ADS)

    Mori, Takahiro; Mizubayashi, Wataru; Morita, Yukinori; Migita, Shinji; Fukuda, Koichi; Miyata, Noriyuki; Yasuda, Tetsuji; Masahara, Meishoku; Ota, Hiroyuki

    2015-03-01

    A tunneling-current enhancement technology for Si-based tunnel field-effect transistors (TFETs) utilizing an Al-N isoelectronic trap (IET) has been proposed recently. In this study, we investigate hot implantation as a doping technique for Al-N isoelectronic impurity. Hot implantation reduces the damage induced by Al and N implantation processes, resulting in performance improvement of IET-assisted TFETs, e.g., a 12-fold enhancement in the driving current at an operation voltage of 0.5 V and an approximately one-third reduction in the subthreshold slope. By hot implantation, we can achieve a higher driving current in Si-based TFETs using the IET technology.

  20. Feynman's wobbling plate

    NASA Astrophysics Data System (ADS)

    Tuleja, Slavomir; Gazovic, Boris; Tomori, Alexander; Hanc, Jozef

    2007-03-01

    In the book Surely You Are Joking, Mr. Feynman! Richard Feynman tells a story of a Cornell cafeteria plate being tossed into the air. As the plate spun, it wobbled. Feynman noticed a relation between the two motions. He solved the motion of the plate by using the Lagrangian approach. This solution didn't satisfy him. He wanted to understand the motion of the plate by analyzing the motion of its individual particles and the forces acting on them. He was successful, but he didn't tell us how he did it. We provide an elementary explanation for the two-to-one ratio of wobble to spin frequencies, based on an analysis of the motion of the particles and the forces acting on them. We also demonstrate the power of numerical simulation and computer animation to provide insight into a physical phenomenon and guidance on how to do the analysis.

  1. Kinetics of MN-based sorbents for hot coal gas desulfurization. Semiannual report, December 15, 1996--March 15, 1997

    SciTech Connect

    Hepworth, M.T.

    1997-03-01

    Manganese-based sorbents have been investigated for the removal of hydrogen sulfide (the primary sulfur bearing compound) from hot coal gases prior to its use in combined cycle turbines. Four formulations of Mn-based sorbents were tested in an ambient-pressure fixed-bed reactor to determine steady state H{sub 2}S concentrations, breakthrough times and effectiveness of the sorbent when subjected to cyclic sulfidation and regeneration testing. In previous reports, the sulfidation and regeneration results from cyclic testing done at 600{degrees}C were presented. Manganese-based sorbents with molar ratios >1:1 Mn:substrate were effective in reducing the H{sub 2}S concentration in simulated coal gases to less than 100 ppmv over five cycles. Actual breakthrough time for formulation C6-2-1100 was as high as 73% of breakthrough time based on wt% Mn in sorbent. Regeneration tests determined that loaded pellets can be fully regenerated in air/steam mixture at 750{degrees}C with minimal sulfate formation. In this report, the results from the cyclic crush strength tests, sulfur profile test, and cyclic testing done after 5 cycles showed decreases in strength from 12.6% to 57.9%. Cyclic testing at 550{degrees}C showed pre-breakthrough concentrations as low as 10 ppmv. Cyclic testing done at 2 L/min and 3 L/min did not show any significant difference in pre-breakthrough concentrations or capacity.

  2. An improved thermal network model of the IGBT module for wind power converters considering the effects of base plate solder fatigue

    NASA Astrophysics Data System (ADS)

    Li, H.; Hu, Y. G.; Liu, S. Q.; Li, Y.; Liao, X. L.; Liu, Z. X.

    2016-08-01

    This study presents an improved thermal network model of the IGBT module that considers the effects of base plate solder fatigue on the junction temperature of the said module used in wind power converters. First, the coupling thermal structure 3D finite element model of the IGBT module is established based on the structure and material parameters of the module used in the wind power converters of a doubly fed induction generator. The junction temperature of the module is also investigated at different thermal desquamating degrees of the base plate solder. Second, the thermal resistance parameters are determined at different desquamating degrees, and the improved thermal network model that considers the effects of base plate solder fatigue is established. Finally, the two results of the calculation of the junction temperature are compared in different fatigue stages through the improved thermal network model and the 3D finite element model, which testify to the effectiveness of the improved thermal network model.

  3. Determination of Iron Ion in the Water of a Natural Hot Spring Using Microfluidic Paper-based Analytical Devices.

    PubMed

    Ogawa, Kazuma; Kaneta, Takashi

    2016-01-01

    Microfluidic paper-based analytical devices (μPADs) were used to detect the iron ion content in the water of a natural hot spring in order to assess the applicability of this process to the environmental analysis of natural water. The μPADs were fabricated using a wax printer after the addition of hydroxylamine into the detection reservoirs to reduce Fe(3+) to Fe(2+), 1,10-phenanthroline for the forming of a complex, and poly(acrylic acid) for ion-pair formation with an acetate buffer (pH 4.7). The calibration curve of Fe(3+) showed a linearity that ranged from 100 to 1000 ppm in the semi-log plot whereas the color intensity was proportional to the concentration of Fe(3+) and ranged from 40 to 350 ppm. The calibration curve represented the daily fluctuation in successive experiments during four days, which indicated that a calibration curve must be constructed for each day. When freshly prepared μPADs were compared with stored ones, no significant difference was found. The μPADs were applied to the determination of Fe(3+) in a sample of water from a natural hot spring. Both the accuracy and the precision of the μPAD method were evaluated by comparisons with the results obtained via conventional spectrophotometry. The results of the μPADs were in good agreement with, but less precise than, those obtained via conventional spectrophotometry. Consequently, the μPADs offer advantages that include rapid and miniaturized operation, although the precision was poorer than that of conventional spectrophotometry.

  4. Field-based evaluations of horizontal flat-plate fish screens

    USGS Publications Warehouse

    Rose, B.P.; Mesa, M.G.; Barbin-Zydlewski, G.

    2008-01-01

    Diversions from streams are often screened to prevent the loss of or injury to fish. Hydraulic criteria meant to protect fish that encounter screens have been developed, but primarily for screens that are vertical to the water flow rather than horizontal. For this reason, we measured selected hydraulic variables and released wild rainbow trout Oncorhynchus mykiss over two types of horizontal flat-plate fish screens in the field. Our goal was to assess the efficacy of these screens under a variety of conditions in the field and provide information that could be used to develop criteria for safe fish passage. We evaluated three different invertedweir screens over a range of stream (0.24-1.77 m3/s) and diversion flows (0.10-0.31 m3/s). Approach velocities (AVs) ranged from 3 to 8 cm/s and sweeping velocities (SVs) from 69 to 143 cm/s. We also evaluated a simple backwatered screen over stream flows of 0.23-0.79 m3/s and diversion flows of 0.08-0.32 m3/s. The mean SVs for this screen ranged from 15 to 66 cm/s and the mean AVs from 1 to 5 cm/s. The survival rates of fish held for 24 h after passage over these screens exceeded 98%. Overall, the number of fish-screen contacts was low and the injuries related to passage were infrequent and consisted primarily of minor fin injuries. Our results indicate that screens of this type have great potential as safe and effective fish screens for small diversions. Care must be taken, however, to avoid operating conditions that produce shallow or no water over the screen surface, situations of high AVs and low SVs at backwatered screens, and situations producing a localized high AV with spiraling flow. ?? Copyright by the American Fisheries Society 2008.

  5. Hypervelocity impact on shielded plates

    NASA Technical Reports Server (NTRS)

    Smith, James P.

    1993-01-01

    A ballistic limit equation for hypervelocity impact on thin plates is derived analytically. This equation applies to cases of impulsive impact on a plate that is protected by a multi-shock shield, and it is valid in the range of velocity above 6 km/s. Experimental tests were conducted at the NASA Johnson Space Center on square aluminum plates. Comparing the center deflections of these plates with the theoretical deflections of a rigid-plastic plate subjected to a blast load, one determines the dynamic yield strength of the plate material. The analysis is based on a theory for the expansion of the fragmented projectile and on a simple failure criterion. Curves are presented for the critical projectile radius versus the projectile velocity, and for the critical plate thickness versus the velocity. These curves are in good agreement with curves that have been generated empirically.

  6. Kinetics of Mn-based sorbents for hot coal gas desulfurization. Quarterly progress report, July 15, 1995--September 15, 1995

    SciTech Connect

    Hepworth, M.T.

    1995-09-15

    The Morgantown Energy Technology Center (METC) of the U.S. Department of Energy (DOE) is actively pursuing the development of reliable and cost-effective processes to clean coal gasifier gases for application to integrated gasification combined cycle (IGCC) and molten carbonate fuel cell (MCFC) power plants. A large portion of gas cleanup research has been directed towards hot gas desulfurization using Zn-based sorbents. However, zinc titinate sorbents undergo reduction to the metal at temperatures approaching 700{degrees}C. In addition, sulfate formation during regeneration leads to spalling of reactive 293 surfaces. Due to zinc-based sorbent performance, METC has shown interest in formulating and testing manganese-based sorbents. Westmoreland and Harrison evaluated numerous candidate sulfur sorbents and identified Mn as a good candidate. Later, Turkdogan and Olsson tested manganese-based sorbents which demonstrated superior desulfurization capacity under high temperatures, and reducing conditions. Recently, Ben-Slimane and Hepworth conducted several studies on formulating Mn-sorbents and desulfurizing a simulated fuel gas. Although thermodynamics predicts higher over-pressures with Mn verses Zn, under certain operating conditions Mn-based sorbents may obtain < 20 ppmv. In addition, the manganese-sulfur-oxygen (Mn-S-O) system does not reduce to the metal under even highly reducing gases at high temperatures (550-900{degrees}C). Currently, many proposed IGCC processes include a water quench prior to desulfurization. This is for two reasons; limitations in the process hardware (1000{degrees}C), and excessive Zn-based sorbent loss (about 700{degrees}C). With manganese the water quench is obviated due to sorbent loss, as Mn-based sorbents have been shown to retain reactivity under cycling testing at 900{degrees}C. This reduces system hardware, and increases thermal efficiency while decreasing the equilibrium H{sub 2}S over-pressure obtainable with a manganese sorbent.

  7. How mantle slabs drive plate tectonics.

    PubMed

    Conrad, Clinton P; Lithgow-Bertelloni, Carolina

    2002-10-04

    The gravitational pull of subducted slabs is thought to drive the motions of Earth's tectonic plates, but the coupling between slabs and plates is not well established. If a slab is mechanically attached to a subducting plate, it can exert a direct pull on the plate. Alternatively, a detached slab may drive a plate by exciting flow in the mantle that exerts a shear traction on the base of the plate. From the geologic history of subduction, we estimated the relative importance of "pull" versus "suction" for the present-day plates. Observed plate motions are best predicted if slabs in the upper mantle are attached to plates and generate slab pull forces that account for about half of the total driving force on plates. Slabs in the lower mantle are supported by viscous mantle forces and drive plates through slab suction.

  8. WormAssay: a novel computer application for whole-plate motion-based screening of macroscopic parasites.

    PubMed

    Marcellino, Chris; Gut, Jiri; Lim, K C; Singh, Rahul; McKerrow, James; Sakanari, Judy

    2012-01-01

    Lymphatic filariasis is caused by filarial nematode parasites, including Brugia malayi. Adult worms live in the lymphatic system and cause a strong immune reaction that leads to the obstruction of lymph vessels and swelling of the extremities. Chronic disease leads to the painful and disfiguring condition known as elephantiasis. Current drug therapy is effective against the microfilariae (larval stage) of the parasite, but no drugs are effective against the adult worms. One of the major stumbling blocks toward developing effective macrofilaricides to kill the adult worms is the lack of a high throughput screening method for candidate drugs. Current methods utilize systems that measure one well at a time and are time consuming and often expensive. We have developed a low-cost and simple visual imaging system to automate and quantify screening entire plates based on parasite movement. This system can be applied to the study of many macroparasites as well as other macroscopic organisms.

  9. WormAssay: A Novel Computer Application for Whole-Plate Motion-based Screening of Macroscopic Parasites

    PubMed Central

    Marcellino, Chris; Gut, Jiri; Lim, K. C.; Singh, Rahul; McKerrow, James; Sakanari, Judy

    2012-01-01

    Lymphatic filariasis is caused by filarial nematode parasites, including Brugia malayi. Adult worms live in the lymphatic system and cause a strong immune reaction that leads to the obstruction of lymph vessels and swelling of the extremities. Chronic disease leads to the painful and disfiguring condition known as elephantiasis. Current drug therapy is effective against the microfilariae (larval stage) of the parasite, but no drugs are effective against the adult worms. One of the major stumbling blocks toward developing effective macrofilaricides to kill the adult worms is the lack of a high throughput screening method for candidate drugs. Current methods utilize systems that measure one well at a time and are time consuming and often expensive. We have developed a low-cost and simple visual imaging system to automate and quantify screening entire plates based on parasite movement. This system can be applied to the study of many macroparasites as well as other macroscopic organisms. PMID:22303493

  10. Single beam grating coupled interferometry: high resolution miniaturized label-free sensor for plate based parallel screening.

    PubMed

    Patko, Daniel; Cottier, Kaspar; Hamori, Andras; Horvath, Robert

    2012-10-08

    Grating Coupled Interferometry (GCI) using high quality waveguides with two incoupling and one outcoupling grating areas is introduced to increase and precisely control the sensing length of the device; and to make the sensor design suitable for plate-based multiplexing. In contrast to other interferometric arrangements, the sensor chips are interrogated with a single expanded laser beam illuminating both incoupling gratings simultaneously. In order to obtain the interference signal, only half of the beam is phase modulated using a laterally divided two-cell liquid crystal modulator. The developed highly symmetrical arrangement of the interferometric arms increases the stability and at the same time offers straightforward integration of parallel sensing channels. The device characteristics are demonstrated for both TE and TM polarized modes.

  11. Long-term high-velocity oxidation and hot corrosion testing of several NiCrAl and FeCrAl base oxide dispersion strengthened alloys

    NASA Technical Reports Server (NTRS)

    Lowell, C. E.; Deadmore, D. L.; Whittenberger, J. D.

    1982-01-01

    Several oxide dispersion strengthened (ODS) alloys have been tested for cyclic, long-term, high gas-velocity resistance to oxidation at 1100 C and hot corrosion at 900 C. Both nominally Ni-16Cr-4Al and Fe-20Cr-4.5Al ODS alloys were subjected up to about 2500 cycles, where each cycle consisted of 1 hr in a hot, Mach 0.3 combusted gas stream followed by a 3-min quench in an ambient temperature, Mach 0.3 air blast. For comparison to existing technology, a coated superalloy was simultaneously tested. The ODS iron alloy exhibited clearly superior behavior, surviving 3800 oxidation and 2300 hot corrosion cycles essentially unscathed. While the ODS nickel alloys exhibited adequate oxidation resistance, the long-term hot corrosion resistance could be marginal, since the best life for such alloys under these conditions was only about 1100 cycles. However, the hot corrosion resistance of the ODS Ni-base alloys is excellent in comparison to that of traditional superalloys.

  12. Development of a calcium-based sorbent for hot gas cleanup. Semi-annual technical progress report, October 1, 1996--March 31, 1997

    SciTech Connect

    Wheelock, T.D.; Doraiswamy, L.K.; Constant, K.

    1997-03-01

    Work has started on the development of a superior calcium-based sorbent for use in hot gas cleanup in IGCC systems. The aim is to develop a sorbent which will remove H{sub 2}S and COS from hot coal gas and be capable of repeated loading and regeneration. Porous alumina pellets and other porous refractory materials will be impregnated with calcium to prepare sorbents for testing. A preliminary review of the literature suggests that such materials have not been investigated extensively for cleaning coal gas.

  13. Physics-Based Constitutive Model to Predict Dynamic Recovery Behavior of BFe10-1-2 Cupronickel Alloy during Hot Working

    NASA Astrophysics Data System (ADS)

    Cai, Jun; Zhang, Xiaolu; Wang, Kuaishe; Miao, Chengpeng

    2016-11-01

    The hot deformation behavior of BFe10-1-2 cupronickel alloy was investigated over wide ranges of deformation temperature and strain rate. The physics-based constitutive model was developed to predict the dynamic recovery (DRV) behavior of BFe10-1-2 cupronickel alloy at elevated temperatures. In order to verify the validity of the developed constitutive equation, the correlation coefficient (R) and average absolute relative error (AARE) were introduced to make statistics. The results indicated that the developed constitutive equation lead a good agreement between the calculated and experimental data and can accurately characterize the hot DRV behaviors for the BFe10-1-2 cupronickel alloy.

  14. Machinability of hastelloy C-276 using Hot-pressed sintered Ti(C7N3)-based cermet cutting tools

    NASA Astrophysics Data System (ADS)

    Xu, Kaitao; Zou, Bin; Huang, Chuanzhen; Yao, Yang; Zhou, Huijun; Liu, Zhanqiang

    2015-05-01

    C-276 nickel-based alloy is a difficult-to-cut material. In high-speed machining of Hastelloy C-276, notching is a prominent failure mode due to high mechanical properties of work piece, which results in the short tool life and low productivity. In this paper, a newly developed Ti(C7N3)-based cermet insert manufactured by a hot-pressing method is used to machine the C-276 nickel-based alloy, and its cutting performances are studied. Based on orthogonal experiment method, the influence of cutting parameters on tool life, material removal rates and surface roughness are investigated. Experimental research results indicate that the optimal cutting condition is a cutting speed of 50 m/min, depth of cut of 0.4 mm and feed rate of 0.15 mm/r if the tool life and material removal rates are considered comprehensively. In this case, the tool life is 32 min and material removal rates are 3000 mm3/min, which is appropriate to the rough machining. If the tool life and surface roughness are considered, the better cutting condition is a cutting speed of 75 m/min, depth of cut of 0.6 mm and feed rate of 0.1 mm/r. In this case, the surface roughness is 0.59μm. Notch wear, flank wear, chipping at the tool nose, built-up edge(BUE) and micro-cracks are found when Ti(C7N3)-based cermet insert turned Hastelloy C-276. Oxidation, adhesive, abrasive and diffusion are the wear mechanisms, which can be investigated by the observations of scanning electron microscope and energy-dispersive spectroscopy. This research will help to guide studies on the evaluation of machining parameters to further advance the productivity of nickel based alloy Hastelloy C-276 machining.

  15. Theoretical study on the cooperative exciton dissociation process based on dimensional and hot charge-transfer state effects in an organic photocell

    NASA Astrophysics Data System (ADS)

    Shimazaki, Tomomi; Nakajima, Takahito

    2016-06-01

    This paper discusses the exciton dissociation process at the donor-acceptor interface in organic photocells. In our previous study, we introduced a local temperature to handle the hot charge-transfer (CT) state and calculated the exciton dissociation probability based on the 1D organic semiconductor model [T. Shimazaki and T. Nakajima, Phys. Chem. Chem. Phys. 17, 12538 (2015)]. Although the hot CT state plays an essential role in exciton dissociations, the probabilities calculated are not high enough to efficiently separate bound electron-hole pairs. This paper focuses on the dimensional (entropy) effect together with the hot CT state effect and shows that cooperative behavior between both effects can improve the exciton dissociation process. In addition, we discuss cooperative effects with site-disorders and external-electric-fields.

  16. Hot-Spots and Holiness: Faith-Based Topics in Freshman Composition.

    ERIC Educational Resources Information Center

    Worth, Jan

    For an instructor of freshman composition at the University of Michigan at Flint, faith-based writing topics offer particular challenges and sometimes intersect in troubling ways with her own prejudices and personal history as a teacher and as a person. But if handled correctly, she believes that a teacher's interaction with students about…

  17. HOT ELUENT CAPILLARY LIQUID CHROMATOGRAPHY USING ZIRCONIA AND TITANIA BASED STATIONARY PHASES. (R825344)

    EPA Science Inventory

    Abstract

    High speed capillary liquid chromatographic separations using a simple home made system constructed from readily available inexpensive components have been studied. Using thermally stable zirconia and titania based packing, the separation of eight alkylbenzene...

  18. Defect inspection in hot slab surface: multi-source CCD imaging based fuzzy-rough sets method

    NASA Astrophysics Data System (ADS)

    Zhao, Liming; Zhang, Yi; Xu, Xiaodong; Xiao, Hong; Huang, Chao

    2016-09-01

    To provide an accurate surface defects inspection method and make the automation of robust image region of interests(ROI) delineation strategy a reality in production line, a multi-source CCD imaging based fuzzy-rough sets method is proposed for hot slab surface quality assessment. The applicability of the presented method and the devised system are mainly tied to the surface quality inspection for strip, billet and slab surface etcetera. In this work we take into account the complementary advantages in two common machine vision (MV) systems(line array CCD traditional scanning imaging (LS-imaging) and area array CCD laser three-dimensional (3D) scanning imaging (AL-imaging)), and through establishing the model of fuzzy-rough sets in the detection system the seeds for relative fuzzy connectedness(RFC) delineation for ROI can placed adaptively, which introduces the upper and lower approximation sets for RIO definition, and by which the boundary region can be delineated by RFC region competitive classification mechanism. For the first time, a Multi-source CCD imaging based fuzzy-rough sets strategy is attempted for CC-slab surface defects inspection that allows an automatic way of AI algorithms and powerful ROI delineation strategies to be applied to the MV inspection field.

  19. Hot-melt extruded filaments based on pharmaceutical grade polymers for 3D printing by fused deposition modeling.

    PubMed

    Melocchi, Alice; Parietti, Federico; Maroni, Alessandra; Foppoli, Anastasia; Gazzaniga, Andrea; Zema, Lucia

    2016-07-25

    Fused deposition modeling (FDM) is a 3D printing technique based on the deposition of successive layers of thermoplastic materials following their softening/melting. Such a technique holds huge potential for the manufacturing of pharmaceutical products and is currently under extensive investigation. Challenges in this field are mainly related to the paucity of adequate filaments composed of pharmaceutical grade materials, which are needed for feeding the FDM equipment. Accordingly, a number of polymers of common use in pharmaceutical formulation were evaluated as starting materials for fabrication via hot melt extrusion of filaments suitable for FDM processes. By using a twin-screw extruder, filaments based on insoluble (ethylcellulose, Eudragit(®) RL), promptly soluble (polyethylene oxide, Kollicoat(®) IR), enteric soluble (Eudragit(®) L, hydroxypropyl methylcellulose acetate succinate) and swellable/erodible (hydrophilic cellulose derivatives, polyvinyl alcohol, Soluplus(®)) polymers were successfully produced, and the possibility of employing them for printing 600μm thick disks was demonstrated. The behavior of disks as barriers when in contact with aqueous fluids was shown consistent with the functional application of the relevant polymeric components. The produced filaments were thus considered potentially suitable for printing capsules and coating layers for immediate or modified release, and, when loaded with active ingredients, any type of dosage forms.

  20. Trapping in GaN-based metal-insulator-semiconductor transistors: Role of high drain bias and hot electrons

    SciTech Connect

    Meneghini, M. Bisi, D.; Meneghesso, G.; Zanoni, E.

    2014-04-07

    This paper describes an extensive analysis of the role of off-state and semi-on state bias in inducing the trapping in GaN-based power High Electron Mobility Transistors. The study is based on combined pulsed characterization and on-resistance transient measurements. We demonstrate that—by changing the quiescent bias point from the off-state to the semi-on state—it is possible to separately analyze two relevant trapping mechanisms: (i) the trapping of electrons in the gate-drain access region, activated by the exposure to high drain bias in the off-state; (ii) the trapping of hot-electrons within the AlGaN barrier or the gate insulator, which occurs when the devices are operated in the semi-on state. The dependence of these two mechanisms on the bias conditions and on temperature, and the properties (activation energy and cross section) of the related traps are described in the text.

  1. Hot melt extrusion based solid solution approach: Exploring polymer comparison, physicochemical characterization and in-vivo evaluation.

    PubMed

    Fule, Ritesh; Paithankar, Vivek; Amin, Purnima

    2016-02-29

    The objective of this study was to develop solid solution (SSL) using hot-melt extrusion as a continuous manufacturing method. Powder blends of artesunate (ARS) a water insoluble drug with either Soluplus (SOL) or Kollidon VA64 (VA64) and additives in the form of surfactants or plasticizers were extruded to manufacture extrudes. The incorporation of surfactant or plasticizers facilitates smooth extrusion processing of the drug-excipient blend which directly reduced the residence time to form extrudes and works as parameter to control flow of the drug-excipients melt inside the extruder barrel. Differential scanning calorimetry (DSC) and X-ray diffraction (TXRD) analysis revealed the existence of the drug within the extrudes in amorphous state. Scanning electron microscopy (SEM), Raman spectroscopy (RS), Raman imaging (RI) and Atomic force microscopy (AFM) analytical characterization were carry out on the SSL formulations showed a homogeneous drug distribution within the extrudes. (2)D NMR and (1)H NMR studies were undertaken to reveal the possible drug-excipient interactions. The SSL produced via continuous HME processing showed significantly faster release of ARS compared to the pure drug substance. It is observed that F1 SSL (soluplus based) have 66.44 times higher AUC(0-72) and 16.60 times higher Cmax than pure ARS. Also K1 SSL (Kollidon VA64 based) have 62.20 times higher AUC(0-72) and 13.40 times higher Cmax than pure ARS.

  2. GROUND-BASED TRANSIT SPECTROSCOPY OF THE HOT-JUPITER WASP-19b IN THE NEAR-INFRARED

    SciTech Connect

    Bean, Jacob L.; Seifahrt, Andreas; Desert, Jean-Michel; Madhusudhan, Nikku; Chilingarian, Igor; Szentgyorgyi, Andrew; Homeier, Derek

    2013-07-10

    We present ground-based measurements of the transmission and emission spectra of the hot-Jupiter WASP-19b in nine spectroscopic channels from 1.25 to 2.35 {mu}m. The measurements are based on the combined analysis of time-series spectroscopy obtained during two complete transits and two complete secondary eclipses of the planet. The observations were performed with the MMIRS instrument on the Magellan II telescope using the technique of multi-object spectroscopy with wide slits. We compare the transmission and emission data to theoretical models to constrain the composition and thermal structure of the planet's atmosphere. Our measured transmission spectrum exhibits a scatter that corresponds to 1.3 scale heights of the planet's atmosphere, which is consistent with the size of spectral features predicted by theoretical models for a clear atmosphere. We detect the secondary eclipses of the planet at significances ranging from 2.2{sigma} to 14.4{sigma}. The secondary eclipse depths, and the significances of the detections increase toward longer wavelengths. Our measured emission spectrum is consistent with a 2250 K effectively isothermal one-dimensional model for the planet's dayside atmosphere. This model also matches previously published photometric measurements from the Spitzer Space Telescope and ground-based telescopes. These results demonstrate the important role that ground-based observations using multi-object spectroscopy can play in constraining the properties of exoplanet atmospheres, and they also emphasize the need for high-precision measurements based on observations of multiple transits and eclipses.

  3. Solitary wave-based delamination detection in composite plates using a combined granular crystal sensor and actuator

    NASA Astrophysics Data System (ADS)

    Kim, Eunho; Restuccia, Francesco; Yang, Jinkyu; Daraio, Chiara

    2015-12-01

    We experimentally and numerically investigate a diagnostic method for detecting hidden delamination in composite panels, using highly nonlinear solitary waves. Solitary waves are a type of nonlinear waves with strong energy intensity and non-distortive nature, which can be controllably generated in one-dimensional granular crystals. In this study, we use granular crystals as a combined sensor and actuator to detect hidden delamination in carbon fiber reinforced polymer (CFRP) composite panels. Specifically, we locally excite a CFRP composite specimen using the granular crystal as an actuator and measure the reflected waves that carry the specimen’s diagnostic information using the same device as a sensor. We first investigate the effect of the panel’s boundary conditions on the response of the reflected solitary waves. We then investigate the interactions of a solitary wave with delamination hidden in the CFRP composite specimen. Lastly, we define a damage index based on the solitary waves’ responses to identify the location of the hidden delamination in the CFRP composite panel. The solitary wave-based diagnostic method can provide unique merits, such as portable and fast sensing of composites’ hidden damage, thereby with the potential of being used for hot spot monitoring of composite-based structures.

  4. Field monitoring of solar domestic hot water systems based on simple tank temperature measurement

    SciTech Connect

    Burch, J.; Xie, Yuantao; Murley, C.S.

    1995-05-01

    By dynamically measuring solar storage tank temperature(s), the solar storage tank effectively becomes a dynamic calorimeter to measure the energy flows in a solar system. The energy flows include solar loop gain, tank losses, and potentially draw extraction. With one-channel temperature loggers storing data over several days to several weeks, this approach provides low-cost, modest-accuracy performance assessment, useful for determination of savings persistence and diagnostics. Analysis is based upon the tank energy balance, identifying solar gain during the day and tank losses at night. These gains and losses can be compared to expectations based upon prior knowledge, and estimated weather conditions. Diagnostics include controller and pump operation, and excessive nighttime losses. With one point temperature logger, solar gain accuracy is expected to be 20 to 50%, depending on draw frequency and volume. Two examples are shown, a properly operating system and a system with excessive nighttime losses.

  5. Development of a microtiter plate-based glycosaminoglycan array for the investigation of glycosaminoglycan-protein interactions.

    PubMed

    Marson, Andrew; Robinson, David E; Brookes, Patrick N; Mulloy, Barbara; Wiles, Michelle; Clark, Simon J; Fielder, Helen L; Collinson, Lisa J; Cain, Stuart A; Kielty, Catherine M; McArthur, Sally; Buttle, David J; Short, Robert D; Whittle, Jason D; Day, Anthony J

    2009-12-01

    The interactions of glycosaminoglycans (GAGs) with proteins underlie a wide range of important biological processes. However, the study of such binding reactions has been hampered by the lack of a simple frontline analysis technique. Previously, we have reported that cold plasma polymerization can be used to coat microtiter plate surfaces with allyl amine to which GAGs (e.g., heparin) can be noncovalently immobilized retaining their ability to interact with proteins. Here, we have assessed the capabilities of surface coats derived from different ratios of allyl amine and octadiene (100:0 to 0:100) to support the binding of diverse GAGs (e.g., chondroitin-4-sulfate, dermatan sulfate, heparin preparations, and hyaluronan) in a functionally active state. The Link module from TSG-6 was used as a probe to determine the level of functional binding because of its broad (and unique) specificity for both sulfated and nonsulfated GAGs. All of the GAGs tested could bind this domain following their immobilization, although there were clear differences in their protein-binding activities depending on the surface chemistry to which they were adsorbed. On the basis of these experiments, 100% allyl amine was chosen for the generation of a microtiter plate-based "sugar array"; X-ray photoelectron spectroscopy revealed that similar relative amounts of chondroitin-4-sulfate, dermatan sulfate, and heparin (including two selectively de-sulfated derivatives) were immobilized onto this surface. Analysis of four unrelated proteins (i.e., TSG-6, complement factor H, fibrillin-1, and versican) illustrated the utility of this array to determine the GAG-binding profile and specificity for a particular target protein.

  6. Static stability analysis of smart magneto-electro-elastic heterogeneous nanoplates embedded in an elastic medium based on a four-variable refined plate theory

    NASA Astrophysics Data System (ADS)

    Ebrahimi, Farzad; Barati, Mohammad Reza

    2016-10-01

    In this article, a nonlocal four-variable refined plate theory is developed to examine the buckling behavior of nanoplates made of magneto-electro-elastic functionally graded (MEE-FG) materials resting on Winkler-Pasternak foundation. Material properties of nanoplate change in spatial coordinate based on power-law distribution. The nonlocal governing equations are deduced by employing the Hamilton principle. For various boundary conditions, the analytical solutions of nonlocal MEE-FG plates for buckling problem will be obtained based on an exact solution approach. Finally, dependency of buckling response of MEE-FG nanoplate on elastic foundation parameters, magnetic potential, external electric voltage, various boundary conditions, small scale parameter, power-law index, plate side-to-thickness ratio and aspect ratio will be figure out. These results can be advantageous for the mechanical analysis and design of intelligent nanoscale structures constructed from magneto-electro-thermo-elastic functionally graded materials.

  7. Evaluation of resistive-plate-chamber-based TOF-PET applied to in-beam particle therapy monitoring.

    PubMed

    Torres-Espallardo, I; Diblen, F; Rohling, H; Solevi, P; Gillam, J; Watts, D; España, S; Vandenberghe, S; Fiedler, F; Rafecas, M

    2015-05-07

    Particle therapy is a highly conformal radiotherapy technique which reduces the dose deposited to the surrounding normal tissues. In order to fully exploit its advantages, treatment monitoring is necessary to minimize uncertainties related to the dose delivery. Up to now, the only clinically feasible technique for the monitoring of therapeutic irradiation with particle beams is Positron Emission Tomography (PET). In this work we have compared a Resistive Plate Chamber (RPC)-based PET scanner with a scintillation-crystal-based PET scanner for this application. In general, the main advantages of the RPC-PET system are its excellent timing resolution, low cost, and the possibility of building large area systems. We simulated a partial-ring scanner based on an RPC prototype under construction within the Fondazione per Adroterapia Oncologica (TERA). For comparison with the crystal-based PET scanner we have chosen the geometry of a commercially available PET scanner, the Philips Gemini TF. The coincidence time resolution used in the simulations takes into account the current achievable values as well as expected improvements of both technologies. Several scenarios (including patient data) have been simulated to evaluate the performance of different scanners. Initial results have shown that the low sensitivity of the RPC hampers its application to hadron-beam monitoring, which has an intrinsically low positron yield compared to diagnostic PET. In addition, for in-beam PET there is a further data loss due to the partial ring configuration. In order to improve the performance of the RPC-based scanner, an improved version of the RPC detector (modifying the thickness of the gas and glass layers), providing a larger sensitivity, has been simulated and compared with an axially extended version of the crystal-based device. The improved version of the RPC shows better performance than the prototype, but the extended version of the crystal-based PET outperforms all other options.

  8. Evaluation of resistive-plate-chamber-based TOF-PET applied to in-beam particle therapy monitoring

    NASA Astrophysics Data System (ADS)

    Torres-Espallardo, I.; Diblen, F.; Rohling, H.; Solevi, P.; Gillam, J.; Watts, D.; España, S.; Vandenberghe, S.; Fiedler, F.; Rafecas, M.

    2015-05-01

    Particle therapy is a highly conformal radiotherapy technique which reduces the dose deposited to the surrounding normal tissues. In order to fully exploit its advantages, treatment monitoring is necessary to minimize uncertainties related to the dose delivery. Up to now, the only clinically feasible technique for the monitoring of therapeutic irradiation with particle beams is Positron Emission Tomography (PET). In this work we have compared a Resistive Plate Chamber (RPC)-based PET scanner with a scintillation-crystal-based PET scanner for this application. In general, the main advantages of the RPC-PET system are its excellent timing resolution, low cost, and the possibility of building large area systems. We simulated a partial-ring scanner based on an RPC prototype under construction within the Fondazione per Adroterapia Oncologica (TERA). For comparison with the crystal-based PET scanner we have chosen the geometry of a commercially available PET scanner, the Philips Gemini TF. The coincidence time resolution used in the simulations takes into account the current achievable values as well as expected improvements of both technologies. Several scenarios (including patient data) have been simulated to evaluate the performance of different scanners. Initial results have shown that the low sensitivity of the RPC hampers its application to hadron-beam monitoring, which has an intrinsically low positron yield compared to diagnostic PET. In addition, for in-beam PET there is a further data loss due to the partial ring configuration. In order to improve the performance of the RPC-based scanner, an improved version of the RPC detector (modifying the thickness of the gas and glass layers), providing a larger sensitivity, has been simulated and compared with an axially extended version of the crystal-based device. The improved version of the RPC shows better performance than the prototype, but the extended version of the crystal-based PET outperforms all other options.

  9. Strength and corrosion behavior of SiC - based ceramics in hot coal combustion environments

    SciTech Connect

    Breder, K.; Parten, R.J.

    1996-08-01

    As part of an effort to evaluate the use of advanced ceramics in a new generation of coal-fired power plants, four SiC-based ceramics have been exposed to corrosive coal slag in a laboratory furnace and two pilot scale combustors. Initial results indicate that the laboratory experiments are valuable additions to more expensive pilot plant experiments. The results show increased corrosive attack with increased temperature, and that only slight changes in temperature may significantly alter the degree of strength degradation due to corrosive attack. The present results are part of a larger experimental matrix evaluating the behavior of ceramics in the coal combustion environment.

  10. Plate/shell structure topology optimization of orthotropic material for buckling problem based on independent continuous topological variables

    NASA Astrophysics Data System (ADS)

    Ye, Hong-Ling; Wang, Wei-Wei; Chen, Ning; Sui, Yun-Kang

    2017-03-01

    The purpose of the present work is to study the buckling problem with plate/shell topology optimization of orthotropic material. A model of buckling topology optimization is established based on the independent, continuous, and mapping method, which considers structural mass as objective and buckling critical loads as constraints. Firstly, composite exponential function (CEF) and power function (PF) as filter functions are introduced to recognize the element mass, the element stiffness matrix, and the element geometric stiffness matrix. The filter functions of the orthotropic material stiffness are deduced. Then these filter functions are put into buckling topology optimization of a differential equation to analyze the design sensitivity. Furthermore, the buckling constraints are approximately expressed as explicit functions with respect to the design variables based on the first-order Taylor expansion. The objective function is standardized based on the second-order Taylor expansion. Therefore, the optimization model is translated into a quadratic program. Finally, the dual sequence quadratic programming (DSQP) algorithm and the global convergence method of moving asymptotes algorithm with two different filter functions (CEF and PF) are applied to solve the optimal model. Three numerical results show that DSQP&CEF has the best performance in the view of structural mass and discretion.

  11. Plate electronics

    NASA Astrophysics Data System (ADS)

    Carlowicz, Michael

    Using a Cray T3D supercomputer and a simple assumption about the physical character of Earth's mantle, a pair of researchers from the University of California at Berkeley have built a computer model that may help explain why the planet's tectonic plates look the way they do.In creating a three-dimensional numerical simulation of convection in the Earth's interior, UC researchers Hans-Peter Bunge and Mark Richards simplified their model to account for just one major physical effect: that the viscosity of the mantle increases with depth. Reviewing some recent—but not yet widely accepted—seismic data, Bunge and Richards assumed for the sake of the model that the viscosity of the mantle increases by a factor of 30 from the lithosphere to the core-mantle boundary. Relying on that assumption, the pair ran the model for nearly three weeks on a supercomputer at Los Alamos National Laboratory and found that the simulation produced an effect similar to what we see on the surface of Earth. The model produced a surface paralleling the actual width of plates and the geometry of the plate boundaries.

  12. Screening of zinc-based sorbents for hot-gas desulfurization

    SciTech Connect

    Joong B. Lee; Chong K. Ryu; Chang K. Yi; Sung H. Jo; Sung H. Kim

    2008-03-15

    Highly reactive and attrition-resistant ZnO-based sorbents that are suitable for bubbling fluidized-bed reactors can be produced using the spray-drying method. Most of the ZnO-based sorbents prepared here (ZAC-X, X = 18N-25N) satisfy the physical and chemical criteria for bubbling fluidized-bed application (spherical shape, average particle size, 90-110 {mu}m; size distribution, 40-230 {mu}m; bulk density, 0.9-1.0 g/mL; attrition index (AI), 40-80%; sulfur sorption capacity, 14-17 wt %; sorbent use, 70-80%). The performance test of the ZAC-C sorbent at Korea Institute of Energy Research (KIER) with a bubbling fluidized-bed for 70 h also demonstrated that it had good sulfidation and regeneration performance (11 wt % sorption capacity and 52% sorbent use) as well as reasonable attrition resistance (1.1% attrition loss for 70 h). 14 refs., 7 figs., 6 tabs.

  13. Hot Meetings

    NASA Technical Reports Server (NTRS)

    Chiu, Mary

    2002-01-01

    A colleague walked by my office one time as I was conducting a meeting. There were about five or six members of my team present. The colleague, a man who had been with our institution (The Johns Hopkins Applied Physics Lab, a.k.a. APL) for many years, could not help eavesdropping. He said later it sounded like we we re having a raucous argument, and he wondered whether he should stand by the door in case things got out of hand and someone threw a punch. Our Advanced Composition Explorer (ACE) team was a hot group, to invoke the language that is fashionable today, although we never thought of ourselves in those terms. It was just our modus operandi. The tenor of the discussion got loud and volatile at times, but I prefer to think of it as animated, robust, or just plain collaborative. Mary Chiu and her "hot" team from the Johns Hopkins Applied Physics Laboratory built the Advanced Composition Explorer spacecraft for NASA. Instruments on the spacecraft continue to collect data that inform us about what's happening on our most important star, the Sun.

  14. 9. Bronze slide expansion plate at Pier 3, on right, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. Bronze slide expansion plate at Pier 3, on right, fixed end left. - Monongahela Connecting Railroad Company, Hot Metal Bridge, Spanning Monongahela River at mile post 3.1, Pittsburgh, Allegheny County, PA

  15. The polarization modulation and fabrication method of two dimensional silica photonic crystals based on UV nanoimprint lithography and hot imprint

    NASA Astrophysics Data System (ADS)

    Guo, Shuai; Niu, Chunhui; Liang, Liang; Chai, Ke; Jia, Yaqing; Zhao, Fangyin; Li, Ya; Zou, Bingsuo; Liu, Ruibin

    2016-10-01

    Based on a silica sol-gel technique, highly-structurally ordered silica photonic structures were fabricated by UV lithography and hot manual nanoimprint efforts, which makes large-scale fabrication of silica photonic crystals easy and results in low-cost. These photonic structures show perfect periodicity, smooth and flat surfaces and consistent aspect ratios, which are checked by scanning electron microscopy (SEM) and atomic force microscopy (AFM). In addition, glass substrates with imprinted photonic nanostructures show good diffraction performance in both transmission and reflection mode. Furthermore, the reflection efficiency can be enhanced by 5 nm Au nanoparticle coating, which does not affect the original imprint structure. Also the refractive index and dielectric constant of the imprinted silica is close to that of the dielectric layer in nanodevices. In addition, the polarization characteristics of the reflected light can be modulated by stripe nanostructures through changing the incident light angle. The experimental findings match with theoretical results, making silica photonic nanostructures functional integration layers in many optical or optoelectronic devices, such as LED and microlasers to enhance the optical performance and modulate polarization properties in an economical and large-scale way.

  16. The polarization modulation and fabrication method of two dimensional silica photonic crystals based on UV nanoimprint lithography and hot imprint.

    PubMed

    Guo, Shuai; Niu, Chunhui; Liang, Liang; Chai, Ke; Jia, Yaqing; Zhao, Fangyin; Li, Ya; Zou, Bingsuo; Liu, Ruibin

    2016-10-04

    Based on a silica sol-gel technique, highly-structurally ordered silica photonic structures were fabricated by UV lithography and hot manual nanoimprint efforts, which makes large-scale fabrication of silica photonic crystals easy and results in low-cost. These photonic structures show perfect periodicity, smooth and flat surfaces and consistent aspect ratios, which are checked by scanning electron microscopy (SEM) and atomic force microscopy (AFM). In addition, glass substrates with imprinted photonic nanostructures show good diffraction performance in both transmission and reflection mode. Furthermore, the reflection efficiency can be enhanced by 5 nm Au nanoparticle coating, which does not affect the original imprint structure. Also the refractive index and dielectric constant of the imprinted silica is close to that of the dielectric layer in nanodevices. In addition, the polarization characteristics of the reflected light can be modulated by stripe nanostructures through changing the incident light angle. The experimental findings match with theoretical results, making silica photonic nanostructures functional integration layers in many optical or optoelectronic devices, such as LED and microlasers to enhance the optical performance and modulate polarization properties in an economical and large-scale way.

  17. Calculation of the Combined Heat Transfer Coefficient of Hot-face on Cast Iron Cooling Stave Based on Thermal Test

    NASA Astrophysics Data System (ADS)

    Li, Feng-guang; Zhang, Jian-liang; Zuo, Hai-bin; Qin, Xuan; Qi, Cheng-lin

    2017-03-01

    Cooling effects of the cast iron cooling stave were tested with a specially designed experimental furnace under the conditions of different temperatures of 800 °C, 900 °C, 1,000 °C and 1,100 °C as well as different cooling water velocities of 0.5 m·s-1, 1.0 m·s-1, 1.5 m·s-1 and 2.0 m·s-1. Furthermore, the combined heat transfer coefficient of hot-face on cast iron cooling stave (αh-i) was calculated by heat transfer theory based on the thermal test. The calculated αh-i was then applied in temperature field simulation of cooling stave and the simulation results were compared with the experimental data. The calculation of αh-i indicates that αh-i increases rapidly as the furnace temperature increases while it increases a little as the water velocity increases. The comparison of the simulation results with the experimental data shows that the simulation results fit well with the experiment data under different furnace temperatures.

  18. Design of all-optical, hot-electron current-direction-switching device based on geometrical asymmetry.

    PubMed

    Kumarasinghe, Chathurangi S; Premaratne, Malin; Gunapala, Sarath D; Agrawal, Govind P

    2016-02-18

    We propose a nano-scale current-direction-switching device(CDSD) that operates based on the novel phenomenon of geometrical asymmetry between two hot-electron generating plasmonic nanostructures. The proposed device is easy to fabricate and economical to develop compared to most other existing designs. It also has the ability to function without external wiring in nano or molecular circuitry since it is powered and controlled optically. We consider a such CDSD made of two dissimilar nanorods separated by a thin but finite potential barrier and theoretically derive the frequency-dependent electron/current flow rate. Our analysis takes in to account the quantum dynamics of electrons inside the nanorods under a periodic optical perturbation that are confined by nanorod boundaries, modelled as finite cylindrical potential wells. The influence of design parameters, such as geometric difference between the two nanorods, their volumes and the barrier width on quality parameters such as frequency-sensitivity of the current flow direction, magnitude of the current flow, positive to negative current ratio, and the energy conversion efficiency is discussed by considering a device made of Ag/TiO2/Ag. Theoretical insight and design guidelines presented here are useful for customizing our proposed CDSD for applications such as self-powered logic gates, power supplies, and sensors.

  19. Design of all-optical, hot-electron current-direction-switching device based on geometrical asymmetry

    PubMed Central

    Kumarasinghe, Chathurangi S.; Premaratne, Malin; Gunapala, Sarath D.; Agrawal, Govind P.

    2016-01-01

    We propose a nano-scale current-direction-switching device(CDSD) that operates based on the novel phenomenon of geometrical asymmetry between two hot-electron generating plasmonic nanostructures. The proposed device is easy to fabricate and economical to develop compared to most other existing designs. It also has the ability to function without external wiring in nano or molecular circuitry since it is powered and controlled optically. We consider a such CDSD made of two dissimilar nanorods separated by a thin but finite potential barrier and theoretically derive the frequency-dependent electron/current flow rate. Our analysis takes in to account the quantum dynamics of electrons inside the nanorods under a periodic optical perturbation that are confined by nanorod boundaries, modelled as finite cylindrical potential wells. The influence of design parameters, such as geometric difference between the two nanorods, their volumes and the barrier width on quality parameters such as frequency-sensitivity of the current flow direction, magnitude of the current flow, positive to negative current ratio, and the energy conversion efficiency is discussed by considering a device made of Ag/TiO2/Ag. Theoretical insight and design guidelines presented here are useful for customizing our proposed CDSD for applications such as self-powered logic gates, power supplies, and sensors. PMID:26887286

  20. The polarization modulation and fabrication method of two dimensional silica photonic crystals based on UV nanoimprint lithography and hot imprint

    PubMed Central

    Guo, Shuai; Niu, Chunhui; Liang, Liang; Chai, Ke; Jia, Yaqing; Zhao, Fangyin; Li, Ya; Zou, Bingsuo; Liu, Ruibin

    2016-01-01

    Based on a silica sol-gel technique, highly-structurally ordered silica photonic structures were fabricated by UV lithography and hot manual nanoimprint efforts, which makes large-scale fabrication of silica photonic crystals easy and results in low-cost. These photonic structures show perfect periodicity, smooth and flat surfaces and consistent aspect ratios, which are checked by scanning electron microscopy (SEM) and atomic force microscopy (AFM). In addition, glass substrates with imprinted photonic nanostructures show good diffraction performance in both transmission and reflection mode. Furthermore, the reflection efficiency can be enhanced by 5 nm Au nanoparticle coating, which does not affect the original imprint structure. Also the refractive index and dielectric constant of the imprinted silica is close to that of the dielectric layer in nanodevices. In addition, the polarization characteristics of the reflected light can be modulated by stripe nanostructures through changing the incident light angle. The experimental findings match with theoretical results, making silica photonic nanostructures functional integration layers in many optical or optoelectronic devices, such as LED and microlasers to enhance the optical performance and modulate polarization properties in an economical and large-scale way. PMID:27698465

  1. Dynamical ejecta from precessing neutron star-black hole mergers with a hot, nuclear-theory based equation of state

    NASA Astrophysics Data System (ADS)

    Foucart, F.; Desai, D.; Brege, W.; Duez, M. D.; Kasen, D.; Hemberger, D. A.; Kidder, L. E.; Pfeiffer, H. P.; Scheel, M. A.

    2017-02-01

    Neutron star-black hole binaries are among the strongest sources of gravitational waves detectable by current observatories. They can also power bright electromagnetic signals (gamma-ray bursts, kilonovae), and may be a significant source of production of r-process nuclei. A misalignment of the black hole spin with respect to the orbital angular momentum leads to precession of that spin and of the orbital plane, and has a significant effect on the properties of the post-merger remnant and of the material ejected by the merger. We present a first set of simulations of precessing neutron star-black hole mergers using a hot, composition dependent, nuclear-theory based equation of state (DD2). We show that the mass of the remnant and of the dynamical ejecta are broadly consistent with the result of simulations using simpler equations of state, while differences arise when considering the dynamics of the merger and the velocity of the ejecta. We show that the latter can easily be understood from assumptions about the composition of low-density, cold material in the different equations of state, and propose an updated estimate for the ejecta velocity which takes those effects into account. We also present an updated mesh-refinement algorithm which allows us to improve the numerical resolution used to evolve neutron star-black hole mergers.

  2. Design of all-optical, hot-electron current-direction-switching device based on geometrical asymmetry

    NASA Astrophysics Data System (ADS)

    Kumarasinghe, Chathurangi S.; Premaratne, Malin; Gunapala, Sarath D.; Agrawal, Govind P.

    2016-02-01

    We propose a nano-scale current-direction-switching device(CDSD) that operates based on the novel phenomenon of geometrical asymmetry between two hot-electron generating plasmonic nanostructures. The proposed device is easy to fabricate and economical to develop compared to most other existing designs. It also has the ability to function without external wiring in nano or molecular circuitry since it is powered and controlled optically. We consider a such CDSD made of two dissimilar nanorods separated by a thin but finite potential barrier and theoretically derive the frequency-dependent electron/current flow rate. Our analysis takes in to account the quantum dynamics of electrons inside the nanorods under a periodic optical perturbation that are confined by nanorod boundaries, modelled as finite cylindrical potential wells. The influence of design parameters, such as geometric difference between the two nanorods, their volumes and the barrier width on quality parameters such as frequency-sensitivity of the current flow direction, magnitude of the current flow, positive to negative current ratio, and the energy conversion efficiency is discussed by considering a device made of Ag/TiO2/Ag. Theoretical insight and design guidelines presented here are useful for customizing our proposed CDSD for applications such as self-powered logic gates, power supplies, and sensors.

  3. Earth's Decelerating Tectonic Plates (Invited)

    NASA Astrophysics Data System (ADS)

    Forte, A. M.; Moucha, R.; Rowley, D. B.; Quere, S.; Mitrovica, J. X.; Simmons, N. A.; Grand, S. P.

    2009-12-01

    We employ a recently developed convection model constrained by seismic, geodynamic and mineral physics data (Simmons et al., GJI 2009) to explore the impact of time-dependent changes in mantle buoyancy forces on tectonic plate accelerations. This plate-coupled mantle convection model incorporates a viscosity structure that reconciles both glacial isostatic adjustment and global convection-related data sets (Mitrovica & Forte, EPSL 2004) and it successfully reproduces present-day plate velocities, global surface gravity and topography data. This convection model predicts the recent deceleration of several major plates in the Pacific and Indo-Atlantic hemispheres. Independent verification of these predictions is a fundamental test of the plausibility of the buoyancy forces and rheological structure in the convection model. To this end, we consider marine magnetic anomaly and space geodetic constraints on tectonic plate motions to determine a new global map of present-day rates of change of plate velocities. This map shows that several major plates, such as the Pacific, Africa and Nazca plates are presently decelerating and that they contribute to a globally-averaged slowdown in tectonic plate speeds. These joint geologic-geodetic inferences of plate decelerations are consistent with those predicted by our tomography-based convection model.

  4. Development of an Abuse- and Alcohol-Resistant Formulation Based on Hot-Melt Extrusion and Film Coating.

    PubMed

    Jedinger, Nicole; Schrank, Simone; Fischer, Johannes M; Breinhälter, Karlheinz; Khinast, Johannes; Roblegg, Eva

    2016-02-01

    This study focused on the development of flexible (i.e., deformable) multiple-unit pellets that feature (i) a prolonged drug release, (ii) drug abuse deterrence, and (iii) a minimal risk of alcohol-induced dose dumping (ADD). Deformable pellets were prepared via an advanced continuous one-step hot-melt extrusion (HME) technique, with the drug (i.e., antipyrine and codeine phosphate) fed as an aqueous solution into the molten matrix material (i.e., cornstarch, gum arabic, and xanthan). Formulations that had suitable mechanical characteristics (i.e., high compression strength) were coated with a flexible Aquacoat(®) ARC film to ensure prolonged release and to avoid ADD. The pellets were characterized in terms of their mechanical properties and in vitro drug release behavior in alcoholic media. All formulations were abuse deterrent: they had a high compression strength and grinding the pellets into powder was impossible. Since the pellets comprising gum arabic and xanthan as a matrix did not remain intact during dissolution testing, they had a very fast drug release rate. Cornstarch-based pellets that swelled but remained intact in the dissolution media had a slower drug release. Coated cornstarch-based pellets had a prolonged release over 8 h and resistance to dose dumping in 20 and 40% ethanol. Our results indicate that cornstarch-based pellets manufactured via the advanced HME process followed by coating are a promising formulation that makes tampering difficult due to a high compression strength combined with robustness in alcoholic media.

  5. Geolocating thermal binoculars based on a software defined camera core incorporating HOT MCT grown by MOVPE

    NASA Astrophysics Data System (ADS)

    Pillans, Luke; Harmer, Jack; Edwards, Tim; Richardson, Lee

    2016-05-01

    Geolocation is the process of calculating a target position based on bearing and range relative to the known location of the observer. A high performance thermal imager with integrated geolocation functions is a powerful long range targeting device. Firefly is a software defined camera core incorporating a system-on-a-chip processor running the AndroidTM operating system. The processor has a range of industry standard serial interfaces which were used to interface to peripheral devices including a laser rangefinder and a digital magnetic compass. The core has built in Global Positioning System (GPS) which provides the third variable required for geolocation. The graphical capability of Firefly allowed flexibility in the design of the man-machine interface (MMI), so the finished system can give access to extensive functionality without appearing cumbersome or over-complicated to the user. This paper covers both the hardware and software design of the system, including how the camera core influenced the selection of peripheral hardware, and the MMI design process which incorporated user feedback at various stages.

  6. Multichannel reconfigurable measurement system for hot plasma diagnostics based on GEM-2D detector

    NASA Astrophysics Data System (ADS)

    Wojenski, A. J.; Kasprowicz, G.; Pozniak, K. T.; Byszuk, A.; Chernyshova, M.; Czarski, T.; Jablonski, S.; Juszczyk, B.; Zienkiewicz, P.

    2015-12-01

    In the future magnetically confined fusion research reactors (e.g. ITER tokamak), precise determination of the level of the soft X-ray radiation of plasma with temperature above 30 keV (around 350 mln K) will be very important in plasma parameters optimization. This paper presents the first version of a designed spectrography measurement system. The system is already installed at JET tokamak. Based on the experience gained from the project, the new generation of hardware for spectrography measurements, was designed and also described in the paper. The GEM detector readout structure was changed to 2D in order to perform measurements of i.e. laser generated plasma. The hardware structure of the system was redesigned in order to provide large number of high speed input channels. Finally, this paper also covers the issue of new control software, necessary to set-up a complete system of certain complexity and perform data acquisition. The main goal of the project was to develop a new version of the system, which includes upgraded structure and data transmission infrastructure (i.e. handling large number of measurement channels, high sampling rate).

  7. Performance study of the fast timing Cherenkov detector based on a microchannel plate PMT

    NASA Astrophysics Data System (ADS)

    Finogeev, D. A.; Grigoriev, V. A.; Kaplin, V. A.; Karavichev, O. V.; Karavicheva, T. L.; Konevskikh, A. S.; Kurepin, A. B.; Kurepin, A. N.; Loginov, V. A.; Mayevskaya, A. I.; Melikyan, Yu A.; Morozov, I. V.; Serebryakov, D. V.; Shabanov, A. I.; Slupecki, M.; Tikhonov, A. A.; Trzaska, W. H.

    2017-01-01

    Prototype of the fast timing Cherenkov detector, applicable in high-energy collider experiments, has been developed basing on the modified Planacon XP85012 MCP-PMT and fused silica radiators. We present the reasons and description of the MCP-PMT modification, timing and amplitude characteristics of the prototype including the summary of the detector’s response on particle hits at oblique angles and MCP-PMT performance at high illumination rates.

  8. Partially light-controlled imager based on liquid crystal plate and image intensifier for aurora and airglow measurement.

    PubMed

    Tang, Yuanhe; Cao, Xiangang; Liu, Hanchen; Shepherd, G G; Liu, Shulin; Gao, Haiyang; Yang, Xusan; Wu, Yong; Wang, Shuiwei

    2012-04-20

    In order to obtain information both of aurora and airglow in one image by the same detector, a PLCI based on liquid crystal plate LCP and super second-generation image intensifier SSGII is proposed in this research. The detection thresholds of the CCD for aurora and airglow are calculated. For the detectable illumination range of 10(4)-10(-2) lx, the corresponding electron count is 1.57×10(5) - 0.2 for every pixel of CCD. The structure and work principle of the PLCI are described. An LC is introduced in the front of CCD to decrease the intensities of aurora in overexposure areas by means of controlling transmittances pixel by pixel, while an image intensifier is set between the LC and CCD to increase the intensity of the weak airglow. The modulation transfer function MTF of this system is calculated as 0.391 at a Nyquist frequency of 15 lp/mm. The curve of transmittance with regard to gray level for the LC is obtained by calibration experiment. Based on the design principle, the prototype is made and used to take photos of objects under strong light greater than 2×10(5) lx. The clear details of [symbols: see text] presented in the image indicate that the PLCI can greatly improve the imaging quality. The theoretical calculations and experiment results prove that this device can extend the dynamic range and it provides a more effective method for upper atmospheric wind measurement.

  9. Molecularly imprinted polymer grafted paper-based multi-disk micro-disk plate for chemiluminescence detection of pesticide.

    PubMed

    Wang, Shoumei; Ge, Lei; Li, Long; Yan, Mei; Ge, Shenguang; Yu, Jinghua

    2013-12-15

    The detection of pesticides has attracted considerable attention in numerous fields, such as environmental monitoring and food safety. Although traditional sensors for pesticides have been widely explored due to their high sensitivity and specificity, it is still challenging to develop a low-cost, portable, fast, and easy-to-use detection method for the public use at home or in the field. To address these challenges, herein, we report a novel paper-based molecular imprinted polymer (MIP)-grafted multi-disk micro-disk plate (P-MIP-MMP) for sensitive and specific chemiluminescence (CL) detection of pesticides through an indirect competitive assay using 2,4-dichlorophenoxyacetic acid (2,4-D) as a proof-of-concept analyte. The MIP-grafted paper disks were prepared by a simple in situ polymerization of MIP layer on the surface of cellulose fibers in paper. The quantification mechanism of this P-MIP-MMP is based on a competition between free 2,4-D and tobacco peroxidase (TOP) labeled 2,4-D and the enzyme catalyzed CL emission from the luminol-TOP-H2O2 CL system. At optimal conditions, this P-MIP-MMP can detect 2,4-D at the concentration of femtomolar level. This approach provided a powerful protocol for simple, low-cost, rapid, and high-throughput detection of pesticides in real samples with satisfactory results for use in areas such as food inspection and environmental monitoring.

  10. Neuroplasticity in dynamic neural networks comprised of neurons attached to adaptive base plate.

    PubMed

    Joghataie, Abdolreza; Shafiei Dizaji, Mehrdad

    2016-03-01

    In this paper, a learning algorithm is developed for Dynamic Plastic Continuous Neural Networks (DPCNNs) to improve their learning of highly nonlinear time dependent problems. A DPCNN is comprised of a base medium, which is nonlinear and plastic, and a number of neurons that are attached to the base by wire-like connections similar to perceptrons. The information is distributed within DPCNNs gradually and through wave propagation mechanism. While a DPCNN is adaptive due to its connection weights, the material properties of its base medium can also be adjusted to improve its learning. The material of the medium is plastic and can contribute to memorizing the history of input-response similar to neuroplasticity in natural brain. The results obtained from numerical simulation of DPCNNs have been encouraging. Nonlinear plastic finite element modeling has been used for numerical simulation of dynamic behavior and wave propagation in the medium. Two significant differences of DPCNNs with other types of neural networks are that: (1) there is a medium to which the neurons are attached where the medium can contribute to the learning, (2) the input layer is not made of nodes but it is an edge terminal which is capable of receiving a continuous function over the input edge, though it is discretized in the finite element model. A DPCNN is reduced to a perceptron if the medium is removed and the neurons are connected to each other only by wires. Continuity of the input lets the discretization of data take place intrinsically within the DPCNN instead of being applied by the user.

  11. An InDel-based linkage map of hot pepper (Capsicum annuum).

    PubMed

    Li, Weipeng; Cheng, Jiaowen; Wu, Zhiming; Qin, Cheng; Tan, Shu; Tang, Xin; Cui, Junjie; Zhang, Li; Hu, Kailin

    Two independent pepper (Capsicum annuum) genomes were published recently, opening a new era of molecular genetics research on pepper. However, pepper molecular marker technologies are still mainly focusing on the simple sequence repeats derived from public database or genomic library. The development and application of the third generation marker system such as single nucleotide polymorphisms, structure variations as well as insertion/deletion polymorphisms (InDels) is still in its infancy. In the present study, we developed InDel markers for pepper genetic mapping with the convenience of two whole-genome re-sequenced inbred lines BA3 (C. annuum) and B702 (C. annuum). A total of 154,519 and 149,755 InDel (1-5 bp) sites were identified for BA3 and B702, respectively, by the alignment of re-sequencing reads to Zunla-1 reference genome. Then, 14,498 InDel sites (only 4 and 5 bp) that are different between BA3 and B702 were predicted. Finally, within a random set of 1,000 primer pairs, 251 InDel markers were validated and mapped onto a linkage map using F2 population derived from the intraspecific cross BA3 × B702. The first InDel-based map, named as BB-InDel map, consisted of 12 linkage groups, covered a genetic distance of 1,178.01 cM and the average distance between bin markers was 5.01 cM. Compared to the Zunla-1 reference physical map, high consistency was observed on all 12 chromosomes, and the total length of scaffold anchored and physical distance covered by this map was 299.66 and 2,558.68 Mb, respectively, which accounted for 8.95 and 76.38 % of the Zunla-1 reference genome (3.35 Gb), respectively. Furthermore, 37 scaffolds (total length of 36.21 Mb) from the pseudo-chromosome (P0) of the current genome assembly were newly assigned to the corresponding chromosomes by 40 InDel markers. Thus, this map provided good genome coverage and would be useful for basic and applied research in pepper.

  12. A comparative assessment of different frequency based damage detection in unidirectional composite plates using MFC sensors

    NASA Astrophysics Data System (ADS)

    de Medeiros, Ricardo; Sartorato, Murilo; Vandepitte, Dirk; Tita, Volnei

    2016-11-01

    The basic concept of the vibration based damage identification methods is that the dynamic behaviour of a structure can change if damage occurs. Damage in a structure can alter the structural integrity, and therefore, the physical properties like stiffness, mass and/or damping may change. The dynamic behaviour of a structure is a function of these physical properties and will, therefore, directly be affected by the damage. The dynamic behaviour can be described in terms of time, frequency and modal domain parameters. The changes in these parameters (or properties derived from these parameters) are used as indicators of damage. Hence, this work has two main objectives. The first one is to provide an overview of the structural vibration based damage identification methods. For this purpose, a fundamental description of the structural vibration based damage identification problem is given, followed by a short literature overview of the damage features, which are commonly addressed. The second objective is to create a damage identification method for detection of the damage in composite structures. To aid in this process, two basic principles are discussed, namely the effect of the potential damage case on the dynamic behaviour, and the consequences involved with the information reduction in the signal processing. Modal properties from the structural dynamic output response are obtained. In addition, experimental and computational results are presented for the application of modal analysis techniques applied to composite specimens with and without damage. The excitation of the structures is performed using an impact hammer and, for measuring the output data, accelerometers as well as piezoelectric sensors. Finite element models are developed by shell elements, and numerical results are compared to experimental data, showing good correlation for the response of the specimens in some specific frequency range. Finally, FRFs are analysed using suitable metrics, including a

  13. An adaptive ARX model to estimate the RUL of aluminum plates based on its crack growth

    NASA Astrophysics Data System (ADS)

    Barraza-Barraza, Diana; Tercero-Gómez, Víctor G.; Beruvides, Mario G.; Limón-Robles, Jorge

    2017-01-01

    A wide variety of Condition-Based Maintenance (CBM) techniques deal with the problem of predicting the time for an asset fault. Most statistical approaches rely on historical failure data that might not be available in several practical situations. To address this issue, practitioners might require the use of self-starting approaches that consider only the available knowledge about the current degradation process and the asset operating context to update the prognostic model. Some authors use Autoregressive (AR) models for this purpose that are adequate when the asset operating context is constant, however, if it is variable, the accuracy of the models can be affected. In this paper, three autoregressive models with exogenous variables (ARX) were constructed, and their capability to estimate the remaining useful life (RUL) of a process was evaluated following the case of the aluminum crack growth problem. An existing stochastic model of aluminum crack growth was implemented and used to assess RUL estimation performance of the proposed ARX models through extensive Monte Carlo simulations. Point and interval estimations were made based only on individual history, behavior, operating conditions and failure thresholds. Both analytic and bootstrapping techniques were used in the estimation process. Finally, by including recursive parameter estimation and a forgetting factor, the ARX methodology adapts to changing operating conditions and maintain the focus on the current degradation level of an asset.

  14. Consistency of Field-Based Measures of Neuromuscular Control Using Force-Plate Diagnostics in Elite Male Youth Soccer Players.

    PubMed

    Read, Paul J; Oliver, Jon L; Croix, Mark Ba De Ste; Myer, Gregory D; Lloyd, Rhodri S

    2016-12-01

    Read, P, Oliver, JL, Croix, MD, Myer, GD, and Lloyd, RS. Consistency of field-based measures of neuromuscular control using force-plate diagnostics in elite male youth soccer players. J Strength Cond Res 30(12): 3304-3311, 2016-Deficits in neuromuscular control during movement patterns such as landing are suggested pathomechanics that underlie sport-related injury. A common mode of assessment is measurement of landing forces during jumping tasks; however, these measures have been used less frequently in male youth soccer players, and reliability data are sparse. The aim of this study was to examine the reliability of a field-based neuromuscular control screening battery using force-plate diagnostics in this cohort. Twenty-six pre-peak height velocity (PHV) and 25 post-PHV elite male youth soccer players completed a drop vertical jump (DVJ), single-leg 75% horizontal hop and stick (75%HOP), and single-leg countermovement jump (SLCMJ). Measures of peak landing vertical ground reaction force (pVGRF), time to stabilization, time to pVGRF, and pVGRF asymmetry were recorded. A test-retest design was used, and reliability statistics included change in mean, intraclass correlation coefficient, and coefficient of variation (CV). No significant differences in mean score were reported for any of the assessed variables between test sessions. In both groups, pVGRF and asymmetry during the 75%HOP and SLCMJ demonstrated largely acceptable reliability (CV ≤ 10%). Greater variability was evident in DVJ pVGRF and all other assessed variables, across the 3 protocols (CV range = 13.8-49.7%). Intraclass correlation coefficient values ranged from small to large and were generally higher in the post-PHV players. The results of this study suggest that pVGRF and asymmetry can be reliably assessed using a 75%HOP and SLCMJ in this cohort. These measures could be used to support a screening battery for elite male youth soccer players and for test-retest comparison.

  15. A physically-based continuum damage mechanics model for numerical prediction of damage growth in laminated composite plates

    NASA Astrophysics Data System (ADS)

    Williams, Kevin Vaughan

    Rapid growth in use of composite materials in structural applications drives the need for a more detailed understanding of damage tolerant and damage resistant design. Current analytical techniques provide sufficient understanding and predictive capabilities for application in preliminary design, but current numerical models applicable to composites are few and far between and their development into well tested, rigorous material models is currently one of the most challenging fields in composite materials. The present work focuses on the development, implementation, and verification of a plane-stress continuum damage mechanics based model for composite materials. A physical treatment of damage growth based on the extensive body of experimental literature on the subject is combined with the mathematical rigour of a continuum damage mechanics description to form the foundation of the model. The model has been implemented in the LS-DYNA3D commercial finite element hydrocode and the results of the application of the model are shown to be physically meaningful and accurate. Furthermore it is demonstrated that the material characterization parameters can be extracted from the results of standard test methodologies for which a large body of published data already exists for many materials. Two case studies are undertaken to verify the model by comparison with measured experimental data. The first series of analyses demonstrate the ability of the model to predict the extent and growth of damage in T800/3900-2 carbon fibre reinforced polymer (CFRP) plates subjected to normal impacts over a range of impact energy levels. The predicted force-time and force-displacement response of the panels compare well with experimental measurements. The damage growth and stiffness reduction properties of the T800/3900-2 CFRP are derived using published data from a variety of sources without the need for parametric studies. To further demonstrate the physical nature of the model, a IM6

  16. License plate detection algorithm

    NASA Astrophysics Data System (ADS)

    Broitman, Michael; Klopovsky, Yuri; Silinskis, Normunds

    2013-12-01

    A novel algorithm for vehicle license plates localization is proposed. The algorithm is based on pixel intensity transition gradient analysis. Near to 2500 natural-scene gray-level vehicle images of different backgrounds and ambient illumination was tested. The best set of algorithm's parameters produces detection rate up to 0.94. Taking into account abnormal camera location during our tests and therefore geometrical distortion and troubles from trees this result could be considered as passable. Correlation between source data, such as license Plate dimensions and texture, cameras location and others, and parameters of algorithm were also defined.

  17. The Plate Tectonics Project

    ERIC Educational Resources Information Center

    Hein, Annamae J.

    2011-01-01

    The Plate Tectonics Project is a multiday, inquiry-based unit that facilitates students as self-motivated learners. Reliable Web sites are offered to assist with lessons, and a summative rubric is used to facilitate the holistic nature of the project. After each topic (parts of the Earth, continental drift, etc.) is covered, the students will…

  18. A simple calibration approach based on film-casting for confocal Raman microscopy to support the development of a hot-melt extrusion process.

    PubMed

    Netchacovitch, L; Thiry, J; De Bleye, C; Dumont, E; Dispas, A; Hubert, C; Krier, F; Sacré, P-Y; Evrard, B; Hubert, Ph; Ziemons, E

    2016-07-01

    When developing a new formulation, the development, calibration and validation steps of analytical methods based on vibrational spectroscopy are time-consuming. For each new formulation, real samples must be produced and a "reference method" must be used in order to determine the Active Pharmaceutical Ingredient (API) content of each sample. To circumvent this issue, the paper presents a simple approach based on the film-casting technique used as a calibration tool in the framework of hot-melt extrusion process. Confocal Raman microscopic method was successfully validated for the determination of itraconazole content in film-casting samples. Then, hot-melt extrusion was carried out to produce real samples in order to confront the results obtained with confocal Raman microscopy and Ultra High Performance Liquid Chromatography (UHPLC). The agreement between both methods was demonstrated using a comparison study based on the Bland and Altman's plot.

  19. Cadmium plating replacements

    SciTech Connect

    Nelson, M.J.; Groshart, E.C.

    1995-03-01

    The Boeing Company has been searching for replacements to cadmium plate. Two alloy plating systems seem close to meeting the needs of a cadmium replacement. The two alloys, zinc-nickel and tin-zinc are from alloy plating baths; both baths are neutral pH. The alloys meet the requirements for salt fog corrosion resistance, and both alloys excel as a paint base. Currently, tests are being performed on standard fasteners to compare zinc-nickel and tin-zinc on threaded hardware where cadmium is heavily used. The Hydrogen embrittlement propensity of the zinc-nickel bath has been tested, and just beginning for the tin-zinc bath. Another area of interest is the electrical properties on aluminum for tin-zinc and will be discussed. The zinc-nickel alloy plating bath is in production in Boeing Commercial Airplane Group for non-critical low strength steels. The outlook is promising that these two coatings will help The Boeing Company significantly reduce its dependence on cadmium plating.

  20. Cadmium plating replacements

    NASA Technical Reports Server (NTRS)

    Nelson, Mary J.; Groshart, Earl C.

    1995-01-01

    The Boeing Company has been searching for replacements to cadmium plate. Two alloy plating systems seem close to meeting the needs of a cadmium replacement. The two alloys, zinc-nickel and tin-zinc are from alloy plating baths; both baths are neutral pH. The alloys meet the requirements for salt fog corrosion resistance, and both alloys excel as a paint base. Currently, tests are being performed on standard fasteners to compare zinc-nickel and tin-zinc on threaded hardware where cadmium is heavily used. The Hydrogen embrittlement propensity of the zinc-nickel bath has been tested, and just beginning for the tin-zinc bath. Another area of interest is the electrical properties on aluminum for tin-zinc and will be discussed. The zinc-nickel alloy plating bath is in production in Boeing Commercial Airplane Group for non-critical low strength steels. The outlook is promising that these two coatings will help The Boeing Company significantly reduce its dependence on cadmium plating.

  1. Analysis of saturated and aromatic hydrocarbons migrating from a polyolefin-based hot-melt adhesive into food.

    PubMed

    Lommatzsch, Martin; Biedermann, Maurus; Grob, Koni; Simat, Thomas J

    2016-01-01

    Hot-melt adhesives are widely utilised to glue cardboard boxes used as food packaging material. They have to comply with the requirements of Article 3 of the European Framework Regulation for food contact materials (1935/2004). The hot melt raw materials analysed mainly consisted of paraffinic waxes, hydrocarbon resins and polyolefins. The hydrocarbon resins, functioning as tackifiers, were the predominant source of hydrocarbons of sufficient volatility to migrate into dry foods: the 18 hydrocarbon resins analysed contained 8.2-118 g kg(-1) saturated and up to 59 g kg(-1) aromatic hydrocarbons eluted from GC between n-C16 and n-C24, substantially more than the paraffinic waxes and the polyolefins. These tackfier resins, especially the oligomers ≤ C24, have been characterised structurally by GC×GC-MS and (1)H-NMR spectroscopy. Migration into food was estimated using a simulating system with polenta as food simulant, which was verified by the analysis of a commercial risotto rice sample packed in a virgin fibre folding box sealed with a hot melt. About 0.5-1.5% of the potentially migrating substances (between n-C16 and n-C24) of a hot melt were found to be transferred into food under storage conditions, which can result in a food contamination in the order of 1 mg kg(-1) food (depending on the amount of potentially migrating substances from the hot melt, the hot melt surface, amount of food, contact time etc.). Migrates from hot melts are easily mistaken for mineral oil hydrocarbons from recycled cardboard.

  2. Chloride-based fast homoepitaxial growth of 4H-SiC films in a vertical hot-wall CVD

    NASA Astrophysics Data System (ADS)

    Guoguo, Yan; Feng, Zhang; Yingxi, Niu; Fei, Yang; Xingfang, Liu; Lei, Wang; Wanshun, Zhao; Guosheng, Sun; Yiping, Zeng

    2016-06-01

    Chloride-based fast homoepitaxial growth of 4H-SiC epilayers was performed on 4° off-axis 4H-SiC substrates in a home-made vertical hot-wall chemical vapor deposition (CVD) system using H2-SiH4-C2H4-HCl. The effect of the SiH4/H2 ratio and reactor pressure on the growth rate of 4H-SiC epilayers has been studied successively. The growth rate increase in proportion to the SiH4/H2 ratio and the influence mechanism of chlorine has been investigated. With the reactor pressure increasing from 40 to 100 Torr, the growth rate increased to 52 μm/hand then decreased to 47 μm/h, which is due to the joint effect of H2 and HCl etching as well as the formation of Si clusters at higher reactor pressure. The surface root mean square (RMS) roughness keeps around 1 nm with the growth rate increasing to 49 μm/h. The scanning electron microscope (SEM), Raman spectroscopy and X-ray diffraction (XRD) demonstrate that 96.7 μm thick 4H-SiC layers of good uniformity in thickness and doping with high crystal quality can be achieved. These results prove that chloride-based fast epitaxy is an advanced growth technique for 4H-SiC homoepitaxy. Project supported by the National High Technology R&D Program of China (No. 2014AA041402), the National Natural Science Foundation of China (Nos. 61474113, 61274007, 61574140), the Beijing Natural Science Foundation of China (Nos. 4132076, 4132074), the Program of State Grid Smart Grid Research Institute (No. SGRI-WD-71-14-004), and the Youth Innovation Promotion Association of CAS.

  3. 0.94-2.42 μm ground-based transmission spectra of the hot Jupiter HD-189733b

    SciTech Connect

    Danielski, C.; Waldmann, I. P.; Hollis, M. D. J.; Tinetti, G.; Deroo, P.; Swain, M. R.

    2014-04-10

    We present here new transmission spectra of the hot Jupiter HD-189733b using the SpeX instrument on the NASA Infrared Telescope Facility. We obtained two nights of observations where we recorded the primary transit of the planet in the J, H, and K bands simultaneously, covering a spectral range from 0.94 to 2.42 μm. We used Fourier analysis and other detrending techniques validated previously on other data sets to clean the data. We tested the statistical significance of our results by calculating the autocorrelation function, and we found that, after the detrending, autocorrelative noise is diminished at most frequencies. Additionally, we repeated our analysis on the out-of-transit data only, showing that the residual telluric contamination is well within the error bars. While these techniques are very efficient when multiple nights of observations are combined together, our results prove that even one good night of observations is enough to provide statistically meaningful data. Our observed spectra are consistent with space-based data recorded in the same wavelength interval by multiple instruments, indicating that ground-based facilities are becoming a viable and complementary option to spaceborne observatories. The best fit to the features in our data was obtained with water vapor. Our error bars are not small enough to address the presence of additional molecules; however, by combining the information contained in other data sets with our results, it is possible to explain all the available observations with a modeled atmospheric spectrum containing water vapor, methane, carbon monoxide, and hazes/clouds.

  4. Model-Based IN SITU Parameter Estimation of Ultrasonic Guided Waves in AN Isotropic Plate

    NASA Astrophysics Data System (ADS)

    Hall, James S.; Michaels, Jennifer E.

    2010-02-01

    Most ultrasonic systems employing guided waves for flaw detection require information such as dispersion curves, transducer locations, and expected propagation loss. Degraded system performance may result if assumed parameter values do not accurately reflect the actual environment. By characterizing the propagating environment in situ at the time of test, potentially erroneous a priori estimates are avoided and performance of ultrasonic guided wave systems can be improved. A four-part model-based algorithm is described in the context of previous work that estimates model parameters whereby an assumed propagation model is used to describe the received signals. This approach builds upon previous work by demonstrating the ability to estimate parameters for the case of single mode propagation. Performance is demonstrated on signals obtained from theoretical dispersion curves, finite element modeling, and experimental data.

  5. Holding fixture for a hot stamping press

    NASA Technical Reports Server (NTRS)

    Harris, R. P. (Inventor)

    1983-01-01

    A hand held guide for manually positioning a work piece between the anvil rib and tool of a hot die stamping press is described. A groove completed by interchangeable cover plates attached at one end of the guide conforms to a cross sectional dimension common to similar workpieces and, with a force fit, retentively holds each of the workpieces.

  6. Characterizing intra and inter annual variability of storm events based on very high frequency monitoring of hydrological and chemical variables: what can we learn about hot spots and hot moments from continuous hydro-chemical sensors ?

    NASA Astrophysics Data System (ADS)

    Fovet, O.; Thelusma, G.; Humbert, G.; Dupas, R.; Jaffrezic, A.; Grimaldi, C.; Faucheux, M.; Gilliet, N.; Hamon, Y.; Gruau, G.

    2015-12-01

    Storm events are hot moments of emission for several dissolved and particulate chemical species at major stake for water quality (e.g. dissolved organic carbon DOC, suspended sediments, phosphorus, NH4). During such events, the solutes or particles are exported from heterogeneous sources through various pathways to stream or are possibly stored in retention hot spots temporary. This leads to specific integrated signals at the outlet at the scale of storm events. The dynamics of such events are also very short especially in headwater catchments where their total duration ranges over 10h to 3 days, with very quick variations in stream flow and concentrations at the outlet occurring in a few hours. Thus for investigating properly event processes, high frequency monitoring of flow and water quality is required. We analysed 103 storm events in a 5 km2 agricultural headwater catchment, part of the AgrHys Observatory, on the basis of a 3-year-long data set which combined meterological (Rainfall), hydrological (flow and piezometry), and water quality (turbidity, conductivity, DOC and NO3 concentrations) data recorded at very high frequencies (from 1 to 20 min) thanks to dedicated sensors. We described the storm events using simple (1 variable) and combined (2 variables) descriptors for characterizing level and dynamics of flow (Q), groundwater levels, and concentrations (C) but also the C-Q relationships. Three intra annual periods have been previously defined for base flow dynamic according to shallow groundwater table variations so that they correspond to different connectivity status in the catchment. The seasonal and inter-annual variability of the storm events have been analysed using the descriptors and based on these predefined periods. Principal component analysis based on storm chemical descriptors led to discriminate these three seasons while storm hydrological descriptors are less variable between them. Finally we used a clustering method to build a typology of

  7. The hot plasma spectrometers on Freja

    NASA Astrophysics Data System (ADS)

    Norberg, O.; Eliasson, L.

    1991-11-01

    The hot plasma instrumentation F3H on the Swedish-German Freja satellite due for launch in 1992 will consist of electron and ion spectrometers. The spectrometer Magnetic imaging Two dimensional Electron (MATE) will measure the two dimensional electron distribution in the spin plane in the energy range 0.1 to 120 keV. The ion mass spectrometer Three dimensional Ion Composition Spectrometer (TICS) measures a full three dimensional distribution in the energy range 0.5 to 15000 eV/q with high mass resolution. The instruments use a particle 'imaging' detector technique based on a large diameter microchannel plate with position sensitive anode. The topics to be studied with the Freja hot plasma spectrometers include auroral particle acceleration, heating and acceleration of ionospheric ions, and the dynamics of auroral arc systems. Of special importance to the scientific objectives is the high data rate from the Freja instrumentation, the MATE and TICS spectrometers will be sampled every 10 ms, corresponding to a spatial resolution better than 70 m at ionospheric heights. The design, simulation, and calibration of the spectrometers are discussed.

  8. Distribution of sequence-based types of legionella pneumophila serogroup 1 strains isolated from cooling towers, hot springs, and potable water systems in China.

    PubMed

    Qin, Tian; Zhou, Haijian; Ren, Hongyu; Guan, Hong; Li, Machao; Zhu, Bingqing; Shao, Zhujun

    2014-04-01

    Legionella pneumophila serogroup 1 causes Legionnaires' disease. Water systems contaminated with Legionella are the implicated sources of Legionnaires' disease. This study analyzed L. pneumophila serogroup 1 strains in China using sequence-based typing. Strains were isolated from cooling towers (n = 96), hot springs (n = 42), and potable water systems (n = 26). Isolates from cooling towers, hot springs, and potable water systems were divided into 25 sequence types (STs; index of discrimination [IOD], 0.711), 19 STs (IOD, 0.934), and 3 STs (IOD, 0.151), respectively. The genetic variation among the potable water isolates was lower than that among cooling tower and hot spring isolates. ST1 was the predominant type, accounting for 49.4% of analyzed strains (n = 81), followed by ST154. With the exception of two strains, all potable water isolates (92.3%) belonged to ST1. In contrast, 53.1% (51/96) and only 14.3% (6/42) of cooling tower and hot spring, respectively, isolates belonged to ST1. There were differences in the distributions of clone groups among the water sources. The comparisons among L. pneumophila strains isolated in China, Japan, and South Korea revealed that similar clones (ST1 complex and ST154 complex) exist in these countries. In conclusion, in China, STs had several unique allelic profiles, and ST1 was the most prevalent sequence type of environmental L. pneumophila serogroup 1 isolates, similar to its prevalence in Japan and South Korea.

  9. Direct deposition of GaN-based photocathodes on microchannel plates

    NASA Astrophysics Data System (ADS)

    Dabiran, Amir M.; Wowchak, Andrew M.; Chow, Peter P.; Siegmund, Oswald H. W.; Hull, Jeffrey S.; Malloy, James; Tremsin, Anton S.

    2009-02-01

    Epitaxial growth of p-type GaN-based UV photocathode by RF plasma assisted molecular beam epitaxy (MBE) on sapphire, fused silica, and alumina substrates was investigated. The electrical measurements indicted the growth of highly p-type GaN films as thin as 0.1 μm on c-plane sapphire with a thin AlN nucleation layer. Polycrystalline p-type GaN was obtained for growth on fused silica and alumina. Negative electron affinity (NEA) photocathodes were fabricated by cesium activation of the p-type GaN films in vacuum. Quantum efficiency for UV detection on different substrates was then characterized. To study the integration of UV photocathodes with MCPs, direct deposition of p-type GaN films on glass MCPs were done at low growth temperatures by MBE. The detection efficiency of polycrystalline p- GaN photocathodes in reflection mode was much less than the high quality p-type GaN films on sapphire, however, it was comparable to the detection efficiency of the latter measured in the semitransparent mode. This indicates the potential for fabrication of improved photocathodes with higher gain and better spatial and temporal resolutions.

  10. Neutron Imager and Flux Monitor Based on Micro Channel Plates (MCP) in Electrostatic Mirror Configuration

    NASA Astrophysics Data System (ADS)

    Variale, V.

    In this paper, a new high transparency device based on MCP for the monitoring the flux and spatial profile of a neutron beam will be described. The assembly consists of a carbon foil with a 6Li deposit, placed in the beam, and a MCP equipped with a phosphor screen readout viewed by a CCD camera, placed outside the beam. Secondary emitted electrons (SEE) produced in the carbon foil by the alpha-particles and tritons from the 6Li+n reaction, are deflected to the MCP detector by means of an electrostatic mirror, suitably designed to preserve the spatial resolution. The conductive layer on the phosphor can be used for neutron counting, and to obtain time-of-flight information. A peculiar feature of this device is that the use of an electrostatic mirror minimizes the perturbation of the neutron beam, i.e. absorption and scattering. It can be used at existing time-of-flight (TOF) facilities, in particular at the n_TOF facility at CERN, for monitoring the flux and special profile of the neutron beam in the thermal and epithermal region. In this work, the device principle and design will be presented, together with the main features in terms of resolution and neutron detection efficiency.

  11. Damage detection in plates using the electromechanical impedance technique based on decoupled measurements of piezoelectric transducers

    NASA Astrophysics Data System (ADS)

    Tinoco, Hector A.; Robledo-Callejas, Leonardo; Marulanda, Dairon J.; Serpa, Alberto L.

    2016-12-01

    Electromechanical impedance (EMI) technique plays an important role in the monitoring of structures with piezoelectric transducers (PT). According to the EMI technique, diagnosis and prognosis can be carried out to detect structural modifications in an operative state. However, to develop an efficient methodology for damage detection; damage metrics and patterns should be defined using indices to quantify changes in the signals. In this study, a new approach is proposed considering the electrical impedance (EI) of PT as an array of coupled electrical impedances. It means that when a PT is bonded to a structure, the EI is governed by an electrical circuit that is assumed to be parallel and composed by electrical contributions of both, the structure and the PT. In our perspective, each free PT presents unique mechanical characteristics and those differences may influence the measured electrical signals, therefore the electrical contributions generated by each piezo-transducer are taken into account. To evaluate the electrical decoupling, two methodologies of damage detection are proposed to identify and locate an induced damage. In these methodologies, the damage metrics are based on ellipses of Gaussian confidence. Four experimental tests were performed to evaluate the methodologies, applying two damage intensities. The results show that the partial process of identification of a damage type is a feasible and applicable procedure, moreover the proposed method was able to evidence the damage location..

  12. Comparison of base of support size during gait initiation using force-plate and motion-capture system: A Bland and Altman analysis.

    PubMed

    Yiou, E; Teyssèdre, C; Artico, R; Fourcade, P

    2016-12-08

    This study aimed to estimate the error made by investigators when force-plate data are used to approximate base of support size during gait initiation. Step length and step width obtained with a method based on motion capture system (Kinematics method, considered the "gold standard") and with a method based on the centre of pressure traces obtained from a force-plate (Force-plate method) were purposely compared using descriptive statistics and the Bland and Altman (BA) method. Participants (N=19) performed series of gait initiation in Spontaneous and Maximal Velocity Conditions (SVC and MVC, respectively). BA analysis showed that 1) step length and width biases, corresponding to the difference between the two methods, were very small (<2.1%) in both velocity conditions and 2) the 95% limits of agreement of the BA plots ranged between 10% and 15% in absolute value. Repeated measures ANOVA showed that step length was significantly larger in MVC than in SVC, with no velocity X method interaction. There was no significant effect of the method on both step parameters. The present results suggest that the Force-plate method is sufficiently accurate to compare step parameters across conditions. However, researchers should be aware that non-negligible errors might occur when considering individual data.

  13. Three dimensional mathematical modeling of violin plate surfaces: An approach based on an ensemble of contour lines.

    PubMed

    Piantadosi, Steven

    2017-01-01

    This paper presents an approach to describing the three dimensional shape of a violin plate in mathematical form. The shape description begins with standard contour lines and ends with an equation for a surface in three dimensional space. The traditional specification of cross sectional arching is unnecessary. Advantages of this approach are that it employs simple and universal description of plate geometry and yields a complete, smoothed, precise mathematical equation of the plate that is suitable for modern three dimensional production. It is quite general and suitable for both exterior and interior plate surfaces, yielding the ability to control thicknesses along with shape. This method can produce mathematical descriptions with tolerances easily less than 0.001 millimeters suitable for modern computerized numerical control carving and hand finishing.

  14. Three dimensional mathematical modeling of violin plate surfaces: An approach based on an ensemble of contour lines

    PubMed Central

    2017-01-01

    This paper presents an approach to describing the three dimensional shape of a violin plate in mathematical form. The shape description begins with standard contour lines and ends with an equation for a surface in three dimensional space. The traditional specification of cross sectional arching is unnecessary. Advantages of this approach are that it employs simple and universal description of plate geometry and yields a complete, smoothed, precise mathematical equation of the plate that is suitable for modern three dimensional production. It is quite general and suitable for both exterior and interior plate surfaces, yielding the ability to control thicknesses along with shape. This method can produce mathematical descriptions with tolerances easily less than 0.001 millimeters suitable for modern computerized numerical control carving and hand finishing. PMID:28166230

  15. Numerical studies on sizing/ rating of plate fin heat exchangers for a modified Claude cycle based helium liquefier/ refrigerator

    NASA Astrophysics Data System (ADS)

    Goyal, M.; Chakravarty, A.; Atrey, M. D.

    2017-02-01

    Performance of modern helium refrigeration/ liquefaction systems depends significantly on the effectiveness of heat exchangers. Generally, compact plate fin heat exchangers (PFHE) having very high effectiveness (>0.95) are used in such systems. Apart from basic fluid film resistances, various secondary parameters influence the sizing/ rating of these heat exchangers. In the present paper, sizing calculations are performed, using in-house developed numerical models/ codes, for a set of high effectiveness PFHE for a modified Claude cycle based helium liquefier/ refrigerator operating in the refrigeration mode without liquid nitrogen (LN2) pre-cooling. The combined effects of secondary parameters like axial heat conduction through the heat exchanger metal matrix, parasitic heat in-leak from surroundings and variation in the fluid/ metal properties are taken care of in the sizing calculation. Numerical studies are carried out to predict the off-design performance of the PFHEs in the refrigeration mode with LN2 pre-cooling. Iterative process cycle calculations are also carried out to obtain the inlet/ exit state points of the heat exchangers.

  16. Measurements of hot-electron temperature in laser-irradiated plasmas

    SciTech Connect

    Solodov, A. A.; Yaakobi, B.; Edgell, D. H.; Follett, R. K.; Myatt, J. F.; Sorce, C.; Froula, D. H.

    2016-10-26

    In a recently published work1–3 we reported on measuring the total energy of hot electrons produced by the interaction of a nanosecond laser with planar CH-coated molybdenum targets, using the Mo Kα emission. The temperature of the hot electrons in that work was determined by the high-energy bremsstrahlung [hard x-ray (HXR)] spectrum measured by a three-channel fluorescence-photomultiplier detector (HXRD). In the present work, we replaced the HXRD with a nine-channel image-plate (IP)–based detector (HXIP). For the same conditions (irradiance of the order of 1014 W/cm2; 2-ns pulses) the measured temperatures are consistently lower than those measured by the HXRD (by a factor ~1.5 to 1.7). In addition, we supplemented this measurement with three experiments that measure the hot-electron temperature using Kα line-intensity ratios from high-Z target layers, independent of the HXR emission. These experiments yielded temperatures that were consistent with those measured by the HXIP. We showed that the thermal x-ray radiation must be included in the derivation of total energy in hot electrons (Ehot), and that this makes Ehot only weakly dependent on hot-electron temperature. For a given x-ray emission in inertial confinement fusion compression experiments, this result would lead to a higher total energy in hot electrons, but the preheat of the compressed fuel may be lower because of the reduced hot-electron range.

  17. Droplet-based magnetic bead immunoassay using microchannel-connected multiwell plates (μCHAMPs) for the detection of amyloid beta oligomers.

    PubMed

    Park, Min Cheol; Kim, Moojong; Lim, Gun Taek; Kang, Sung Min; An, Seong Soo A; Kim, Tae Song; Kang, Ji Yoon

    2016-06-21

    Multiwell plates are regularly used in analytical research and clinical diagnosis but often require laborious washing steps and large sample or reagent volumes (typically, 100 μL per well). To overcome such drawbacks in the conventional multiwell plate, we present a novel microchannel-connected multiwell plate (μCHAMP) that can be used for automated disease biomarker detection in a small sample volume by performing droplet-based magnetic bead immunoassay inside the plate. In this μCHAMP-based immunoassay platform, small volumes (30-50 μL) of aqueous-phase working droplets are stably confined within each well by the simple microchannel structure (200-300 μm in height and 0.5-1 mm in width), and magnetic beads are exclusively transported into an adjacent droplet through the oil-filled microchannels assisted by a magnet array aligned beneath and controlled by a XY-motorized stage. Using this μCHAMP-based platform, we were able to perform parallel detection of synthetic amyloid beta (Aβ) oligomers as a model analyte for the early diagnosis of Alzheimer's disease (AD). This platform easily simplified the laborious and consumptive immunoassay procedure by achieving automated parallel immunoassay (32 assays per operation in 3-well connected 96-well plate) within 1 hour and at low sample consumption (less than 10 μL per assay) with no cumbersome manual washing step. Moreover, it could detect synthetic Aβ oligomers even below 10 pg mL(-1) concentration with a calculated detection limit of ∼3 pg mL(-1). Therefore, the μCHAMP and droplet-based magnetic bead immunoassay, with the combination of XY-motorized magnet array, would be a useful platform in the diagnosis of human disease, including AD, which requires low consumption of the patient's body fluid sample and automation of the entire immunoassay procedure for high processing capacity.

  18. Oxidation Characterization of Hafnium-Based Ceramics Fabricated by Hot Pressing and Electric Field-Assisted Sintering

    NASA Technical Reports Server (NTRS)

    Gasch, Matt; Johnson, Sylvia; Marschall, Jochen

    2010-01-01

    Ceramic borides, such as hafnium diboride (HfB2) and zirconium diboride (ZrB2), are members of a family of materials with extremely high melting temperatures referred to as Ultra High Temperature Ceramics (UHTCs). UHTCs constitute a class of promising materials for use in high temperature applications, such as sharp leading edges on future-generation hypersonic flight vehicles, because of their high melting points. The controlled development of microstructure has become important to the processing of UHTCs, with the prospect of improving their mechanical and thermal properties. The improved oxidation resistance of HfB2 has also become important if this material is to be successfully used at temperatures above 2000 C. Furthermore, the use of UHTCs on the leading edges of vehicles traveling at hypersonic speeds will mean exposure to a mixed oxidation environment comprised of both molecular and atomic oxygen. The current study has investigated the high-temperature oxidation behavior of HfB2-based materials in a pure O2 environment, as well as in environments containing different levels of dissociated oxygen (O/O2). Materials were processed by two techniques: conventional hot pressing (HP) and electric field-assisted sintering (FAS). Their oxidation behavior was evaluated in both a tube furnace at 1250 C for 3 hours and in a simulated re-entry environment in the Advanced Heating Facility (AHF) arcjet at NASA Ames Research Center, during a 10-minute exposure to a cold wall heat flux of 250W/sq cm and stagnation pressure of 0.1-0.2 atm. The microstructure of the different materials was characterized before and after oxidation using scanning electron microscopy (SEM).

  19. Effects of the foil flatness on the stress-strain characteristics of U10Mo alloy based monolithic mini-plates

    SciTech Connect

    Hakan Ozaltun; Pavel Medvedev

    2014-11-01

    The effects of the foil flatness on stress-strain behavior of monolithic fuel mini-plates during fabrication and irradiation were studied. Monolithic plate-type fuels are a new fuel form being developed for research and test reactors to achieve higher uranium densities. This concept facilitates the use of low-enriched uranium fuel in the reactor. These fuel elements are comprised of a high density, low enrichment, U–Mo alloy based fuel foil encapsulated in a cladding material made of Aluminum. To evaluate the effects of the foil flatness on the stress-strain behavior of the plates during fabrication, irradiation and shutdown stages, a representative plate from RERTR-12 experiments (Plate L1P756) was considered. Both fabrication and irradiation processes of the plate were simulated by using actual irradiation parameters. The simulations were repeated for various foil curvatures to observe the effects of the foil flatness on the peak stress and strain magnitudes of the fuel elements. Results of fabrication simulations revealed that the flatness of the foil does not have a considerable impact on the post fabrication stress-strain fields. Furthermore, the irradiation simulations indicated that any post-fabrication stresses in the foil would be relieved relatively fast in the reactor. While, the perfectly flat foil provided the slightly better mechanical performance, overall difference between the flat-foil case and curved-foil case was not significant. Even though the peak stresses are less affected, the foil curvature has several implications on the strain magnitudes in the cladding. It was observed that with an increasing foil curvature, there is a slight increase in the cladding strains.

  20. Complete metagenome sequencing based bacterial diversity and functional insights from basaltic hot spring of Unkeshwar, Maharashtra, India

    PubMed Central

    Mehetre, Gajanan T.; Paranjpe, Aditi S.; Dastager, Syed G.; Dharne, Mahesh S.

    2015-01-01

    Unkeshwar hot springs are located at geographical South East Deccan Continental basalt of India. Here, we report the microbial community analysis of this hot spring using whole metagenome shotgun sequencing approach. The analysis revealed a total of 848,096 reads with 212.87 Mbps with 50.87% G + C content. Metagenomic sequences were deposited in SRA database with accession number (SUB1242219). Community analysis revealed 99.98% sequences belonging to bacteria and 0.01% to archaea and 0.01% to Viruses. The data obtained revealed 41 phyla including bacteria and Archaea and including 719 different species. In taxonomic analysis, the dominant phyla were found as, Actinobacteria (56%), Verrucomicrobia (24%), Bacteriodes (13%), Deinococcus-Thermus (3%) and firmicutes (2%) and Viruses (2%). Furthermore, functional annotation using pathway information revealed dynamic potential of hot spring community in terms of metabolism, environmental information processing, cellular processes and other important aspects. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of each contig sequence by assigning KEGG Orthology (KO) numbers revealed contig sequences that were assigned to metabolism, organismal system, Environmental Information Processing, cellular processes and human diseases with some unclassified sequences. The Unkeshwar hot springs offer rich phylogenetic diversity and metabolic potential for biotechnological applications. PMID:26981391

  1. Evaluation of the light scattering and the turbidity microtiter plate-based methods for the detection of the excipient-mediated drug precipitation inhibition.

    PubMed

    Petruševska, Marija; Urleb, Uroš; Peternel, Luka

    2013-11-01

    The excipient-mediated precipitation inhibition is classically determined by the quantification of the dissolved compound in the solution. In this study, two alternative approaches were evaluated, one is the light scattering (nephelometer) and other is the turbidity (plate reader) microtiter plate-based methods which are based on the quantification of the compound precipitate. Following the optimization of the nephelometer settings (beam focus, laser gain) and the experimental conditions, the screening of 23 excipients on the precipitation inhibition of poorly soluble fenofibrate and dipyridamole was performed. The light scattering method resulted in excellent correlation (r>0.91) between the calculated precipitation inhibitor parameters (PIPs) and the precipitation inhibition index (PI(classical)) obtained by the classical approach for fenofibrate and dipyridamole. Among the evaluated PIPs AUC100 (nephelometer) resulted in only four false positives and lack of false negatives. In the case of the turbidity-based method a good correlation of the PI(classical) was obtained for the PIP maximal optical density (OD(max), r=0.91), however, only for fenofibrate. In the case of the OD(max) (plate reader) five false positives and two false negatives were identified. In conclusion, the light scattering-based method outperformed the turbidity-based one and could be reliably used for identification of novel precipitation inhibitors.

  2. Probability-based classifications for spatially characterizing the water temperatures and discharge rates of hot springs in the Tatun Volcanic Region, Taiwan.

    PubMed

    Jang, Cheng-Shin

    2015-05-01

    Accurately classifying the spatial features of the water temperatures and discharge rates of hot springs is crucial for environmental resources use and management. This study spatially characterized classifications of the water temperatures and discharge rates of hot springs in the Tatun Volcanic Region of Northern Taiwan by using indicator kriging (IK). The water temperatures and discharge rates of the springs were first assigned to high, moderate, and low categories according to the two thresholds of the proposed spring classification criteria. IK was then used to model the occurrence probabilities of the water temperatures and discharge rates of the springs and probabilistically determine their categories. Finally, nine combinations were acquired from the probability-based classifications for the spatial features of the water temperatures and discharge rates of the springs. Moreover, various combinations of spring water features were examined according to seven subzones of spring use in the study region. The research results reveal that probability-based classifications using IK provide practicable insights related to propagating the uncertainty of classifications according to the spatial features of the water temperatures and discharge rates of the springs. The springs in the Beitou (BT), Xingyi Road (XYR), Zhongshanlou (ZSL), and Lengshuikeng (LSK) subzones are suitable for supplying tourism hotels with a sufficient quantity of spring water because they have high or moderate discharge rates. Furthermore, natural hot springs in riverbeds and valleys should be developed in the Dingbeitou (DBT), ZSL, Xiayoukeng (XYK), and Macao (MC) subzones because of low discharge rates and low or moderate water temperatures.

  3. Hot Spring Metagenomics

    PubMed Central

    López-López, Olalla; Cerdán, María Esperanza; González-Siso, María Isabel

    2013-01-01

    Hot springs have been investigated since the XIX century, but isolation and examination of their thermophilic microbial inhabitants did not start until the 1950s. Many thermophilic microorganisms and their viruses have since been discovered, although the real complexity of thermal communities was envisaged when research based on PCR amplification of the 16S rRNA genes arose. Thereafter, the possibility of cloning and sequencing the total environmental DNA, defined as metagenome, and the study of the genes rescued in the metagenomic libraries and assemblies made it possible to gain a more comprehensive understanding of microbial communities—their diversity, structure, the interactions existing between their components, and the factors shaping the nature of these communities. In the last decade, hot springs have been a source of thermophilic enzymes of industrial interest, encouraging further study of the poorly understood diversity of microbial life in these habitats. PMID:25369743

  4. 49 CFR 179.300-6 - Thickness of plates.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... psig; S = minimum tensile strength of plate material in p.s.i. as prescribed in § 179.300-7; t... stress in psig (c) If plates are clad with material having tensile strength at least equal to the base... cladding material does not have tensile strength at least equal to the base plate, the base plate...

  5. Novel large format sealed tube microchannel plate detectors for Cherenkov timing and imaging

    NASA Astrophysics Data System (ADS)

    Siegmund, O. H. W.; McPhate, J. B.; Vallerga, J. V.; Tremsin, A. S.; Jelinsky, S. R.; Frisch, H. J.; Lappd Collaboration

    2011-05-01

    Large area (20×20 cm 2) sealed tube detectors using novel borosilicate glass microchannel plates, with bialkali photocathodes and strip-line readouts are being developed for Cherenkov light detection. Designs based on conventional sealed tubes with alumina brazed body construction and hot indium seals have been developed. Borosilicate glass substrates with 20 and 40 μm holes have been processed using atomic layer deposition to produce functional microchannel plates. Initial results for these in a 33 mm format show gain, imaging performance, pulse shape and lifetime characteristics that are similar to standard glass microchannel plates. Large area (20×20 cm 2) borosilicate glass substrates with 20 μm pores have also been made.

  6. BEHAVIOR OF MODEL ASPHALT PAVEMENT CONTAINING A HYDRAULIC, GRADED IRON AND STEEL SLAG BASE-COURSE UNDER REPEATED PLATE-LOADING

    NASA Astrophysics Data System (ADS)

    Yoshida, Nobuyuki; Sugisako, Yasunari

    In this paper, the dynamic response of asphalt pave ment containing a hydraulic, graded iron and steel slag (hereafter called HMS) base-course under repeated plate-loading was investigated using a model asphalt pavement and the influence of hydraulicity on th e pavement behavior was discussed. The model pavement constructed was a 4-layer system consis ting of a dense-graded asphalt mix surface layer, a dense-graded asphalt mix binder-course, a HMS base-course and a Masado (heavily-weathered granitic sand) subgrade. A repeated plate-loading test was carri ed out so as to achieve a resilient state. It is shown that surface resilient deflection decreases as curing progresses and after 90 days, the deflection becomes almost half of the initial. Large horizontal tensile strains develop at the bottoms of binder- and base-course, which decrease significantly with curing. It is indicative that HMS base-course behaves like a stiffer plate resulting in a hard-to-deflect state due to the development of hydraulicity.

  7. Intermittent Plate Tectonics

    NASA Astrophysics Data System (ADS)

    Silver, P. G.; Behn, M. D.

    2006-12-01

    Intermittent Plate Tectonics A basic premise of Earth Science is that plate tectonics has been continuously operating since it began early in Earth's history. Yet, plate-tectonic theory itself, specifically the collisional phase of the Wilson Cycle, constitutes a process that is capable of stopping all plate motion. The plausibility of a plate-tectonic hiatus is most easily illustrated by considering the expected future of the present-day plate-tectonic configuration. Since the opening of the Atlantic at ~200 ma, the area of the Atlantic basin has been growing at the expense of the Pacific. If this trend continues, relative plate motion models predict that in ~350 my, the Pacific Ocean basin will effectively close leading to widespread continent-continent collisions. Since a continent-continent collision represents the termination of subduction locally, the accumulated effect of all collisions is to stop subduction globally. In this scenario, ridges would then stop spreading and young oceanic lithosphere would cool, reaching a steady-state thickness of 100 km in about 80 my, based on the properties of oceanic lithosphere today. This would constitute the stoppage of plate tectonics. The presumption that plate tectonics never stops in the face of continental collisions is equivalent to requiring that subduction flux is approximately constant through time, such that subduction initiation roughly balances subduction termination. Such a balance then raises several questions about the subduction initiation process. When and how does subduction initiate? Is there a detectible relationship between subduction cessation and subduction initiation? We can gain some guidance into these questions by examining the plate motion history over the last 200 my. Subduction initiation has occurred over the last 80 my in three intra- oceanic subduction zones: Aleutians, Marianas-Izu-Bonin and Tonga-Kermadec in the Pacific basin. In these cases, however, subduction initiation would not

  8. Using EarthScope Construction of the Plate Boundary Observatory to Provide Locally Based Experiential Education and Outreach

    NASA Astrophysics Data System (ADS)

    Jackson, M.; Eriksson, S.; Barbour, K.; Venator, S.; Mencin, D.; Prescott, W.

    2006-12-01

    EarthScope is an NSF-funded, national science initiative to explore the structure and evolution of the North American continent and to understand the physical processes controlling earthquakes and volcanoes. This large-scale experiment provides locally based opportunities for education and outreach which engage students at various levels and the public. UNAVCO is responsible for the Plate Boundary Observatory (PBO) component of EarthScope. PBO includes the installation and operations and maintenance of large networks of Global Positioning Satellite (GPS), strainmeter, seismometer, and tiltmeter instruments and the acquisition of satellite radar imagery, all of which will be used to measure and map the smallest movements across faults, the magma movement inside active volcanoes and the very wide areas of deformation associated with plate tectonic motion. UNAVCO, through its own education and outreach activities and in collaboration with the EarthScope E&O Program, uses the PBO construction activities to increase the understanding and public appreciation of geodynamics, earth deformation processes, and their relevance to society. These include programs for public outreach via various media, events associated with local installations, a program to employ students in the construction of PBO, and development of curricular materials by use in local schools associated with the EarthScope geographic areas of focus. PBO provides information to the media to serve the needs of various groups and localities, including interpretive centers at national parks and forests, such as Mt. St. Helens. UNAVCO staff contributed to a television special with the Spanish language network Univision Aquí y Ahora program focused on the San Andreas Fault and volcanoes in Alaska. PBO participated in an Education Day at the Pathfinder Ranch Science and Outdoor Education School in Mountain Center, California. Pathfinder Ranch hosts two of the eight EarthScope borehole strainmeters in the Anza

  9. Effects of the shape of the foil corners on the irradiation performance of U10Mo alloy based monolithic mini-plates

    SciTech Connect

    Ozaltun, Hakan; Medvedev, Pavel G

    2015-06-01

    Monolithic plate-type fuel is a fuel form being developed for high performance research and test reactors to minimize the use of enriched material. These fuel elements are comprised of a high density, low enrichment, U-Mo alloy based fuel foil, sandwiched between Zirconium liners and encapsulated in Aluminum cladding. The use of a high density fuel in a foil form presents a number of fabrication and operational concerns, such as: foil centering, flatness of the foil, fuel thickness variation, geometrical tilting, foil corner shape etc. To benchmark this new design, effects of various geometrical and operational variables on irradiation performance have been evaluated. As a part of these series of sensitivity studies, the shape of the foil corners were studied. To understand the effects of the corner shapes of the foil on thermo-mechanical performance of the plates, a behavioral model was developed for a selected plate from RERTR-12 experiments (Plate L1P785). Both fabrication and irradiation processes were simulated. Once the thermo-mechanical behavior the plate is understood for the nominal case, the simulations were repeated for two additional corner shapes to observe the changes in temperature, displacement and stress-strain fields. The results from the fabrication simulations indicated that the foil corners do not alter the post-fabrication stress-strain magnitudes. Furthermore, the irradiation simulations revealed that post-fabrication stresses of the foil would be relieved very quickly in operation. While, foils with chamfered and filleted corners yielded stresses with comparable magnitudes, they are slightly lower in magnitudes, and provided a more favorable mechanical response compared with the foil with sharp corners.

  10. Corrugated cover plate for flat plate collector

    DOEpatents

    Hollands, K. G. Terry; Sibbitt, Bruce

    1978-01-01

    A flat plate radiant energy collector is providing having a transparent cover. The cover has a V-corrugated shape which reduces the amount of energy reflected by the cover away from the flat plate absorber of the collector.

  11. Continuous production of itraconazole-based solid dispersions by hot melt extrusion: Preformulation, optimization and design space determination.

    PubMed

    Thiry, Justine; Lebrun, Pierre; Vinassa, Chloe; Adam, Marine; Netchacovitch, Lauranne; Ziemons, Eric; Hubert, Philippe; Krier, Fabrice; Evrard, Brigitte

    2016-12-30

    The purpose of this work was to increase the solubility and the dissolution rate of itraconazole, which was chosen as the model drug, by obtaining an amorphous solid dispersion by hot melt extrusion. Therefore, an initial preformulation study was conducted using differential scanning calorimetry, thermogravimetric analysis and Hansen's solubility parameters in order to find polymers which would have the ability to form amorphous solid dispersions with itraconazole. Afterwards, the four polymers namely Kollidon(®) VA64, Kollidon(®) 12PF, Affinisol(®) HPMC and Soluplus(®), that met the set criteria were used in hot melt extrusion along with 25wt.% of itraconazole. Differential scanning confirmed that all four polymers were able to amorphize itraconazole. A stability study was then conducted in order to see which polymer would keep itraconazole amorphous as long as possible. Soluplus(®) was chosen and, the formulation was fine-tuned by adding some excipients (AcDiSol(®), sodium bicarbonate and poloxamer) during the hot melt extrusion process in order to increase the release rate of itraconazole. In parallel, the range limits of the hot melt extrusion process parameters were determined. A design of experiment was performed within the previously defined ranges in order to optimize simultaneously the formulation and the process parameters. The optimal formulation was the one containing 2.5wt.% of AcDiSol(®) produced at 155°C and 100rpm. When tested with a biphasic dissolution test, more than 80% of itraconazole was released in the organic phase after 8h. Moreover, this formulation showed the desired thermoformability value. From these results, the design space around the optimum was determined. It corresponds to the limits within which the process would give the optimized product. It was observed that a temperature between 155 and 170°C allowed a high flexibility on the screw speed, from about 75 to 130rpm.

  12. An aptamer based on-plate microarray for high-throughput insulin detection by MALDI-TOF MS.

    PubMed

    Zhang, Xueyang; Zhu, Shaochun; Deng, Chunhui; Zhang, Xiangmin

    2012-03-11

    An aptamer microarray was directly fabricated on a MALDI target plate for high-throughput insulin detection. High sensitivities were observed both in standard solutions (5 ng mL(-1), 0.86 nM) and serum sample (20 ng mL(-1), 3.4 nM). This method shows great promise in the field of biomarker detection.

  13. A Quantitative High-Throughput 96-well plate Fluorescence Assay for Mechanism-Based Inactivators of Cytochromes P450 Exemplified using CYP2B6

    PubMed Central

    Kenaan, Cesar; Zhang, Haoming; Hollenberg, Paul F.

    2010-01-01

    Mechanism-based inactivators such as bergamottin are useful chemical tools for identifying the roles of specific active-site amino acid residues in the reactions catalyzed by the cytochromes P450 (CYPs or P450s) that are responsible for the metabolism of a wide variety of drugs and endogenous substrates. In clinical settings mechanism-based inactivation of P450s involved in xenobiotic metabolism has the potential to lead to adverse drug-drug interactions and assays to identify and characterize drug candidates as P450 inactivators are important in drug discovery and development. Here we present a quantitative high-throughput protocol for investigating cytochrome P450 mechanism-based inactivators using the example of CYP2B6 and bergamottin to illustrate the finer points of this protocol. This protocol details the adaptation of a 7-ethoxytrifluoromethyl coumarin (7-EFC) O-deethylation fluorescence activity assay to a 96-well microtiter plate format and uses a plate-reader to detect the fluorescence of the product. Compared to previous methods, this protocol requires less P450 and takes significantly less time while greatly increasing throughput. The protocol as written takes approximately two hours to complete. The principles and procedures outlined in this protocol can be easily adapted to other inactivators, P450 isoforms, substrates and plate-readers. PMID:20885377

  14. Growth Plate Fractures

    MedlinePlus

    .org Growth Plate Fractures Page ( 1 ) The bones of children and adults share many of the same risks for injury. But because they ... to a unique injury called a growth plate fracture. Growth plates are areas of cartilage located near ...

  15. FULL SIZE U-10MO MONOLITHIC FUEL FOIL AND FUEL PLATE FABRICATION-TECHNOLOGY DEVELOPMENT

    SciTech Connect

    G. A. Moore; J-F Jue; B. H. Rabin; M. J. Nilles

    2010-03-01

    Full-size U10Mo foils are being developed for use in high density LEU monolithic fuel plates. The application of a zirconium barrier layer too the foil is applied using a hot co-rolling process. Aluminum clad fuel plates are fabricated using Hot Isostatic Pressing (HIP) or a Friction Bonding (FB) process. An overview is provided of ongoing technology development activities, including: the co-rolling process, foil shearing/slitting and polishing, cladding bonding processes, plate forming, plate-assembly swaging, and fuel plate characterization. Characterization techniques being employed include, Ultrasonic Testing (UT), radiography, and microscopy.

  16. Peculiarities of high-pressure and hot-pressing manufacture of MgB2-based blocks with high critical currents for electrical machines

    NASA Astrophysics Data System (ADS)

    Prikhna, T. A.; Gawalek, W.; Savchuk, Ya M.; Sergienko, N. V.; Moshchil, V. E.; Wendt, M.; Habisreuther, T.; Dub, S. N.; Melnikov, V. S.; Kozyrev, A. V.; Schmidt, Ch; Dellith, J.; Litzkendorf, D.; Nagorny, P. A.; Dittrich, U.; Sverdun, V. B.; Kovalev, L. K.; Penkin, V. T.; Goldacker, W.; Rozenberg, O. A.; Noudem, J.

    2008-02-01

    Structure and properties of MgB2-based materials in the form of cylinders, rings, quadratic and rectangular blocks manufactured using high-pressure (2 GPa), hot-pressing (30 MPa), hot isostatic pressing (0.1 GPa), and atmospheric pressure (with predensification by broaching) from different types of B and MgB2 are considered. The blocks have been synthesized from Mg and B or sintered from MgB2 at 800 - 1100 °C (with and without additions of Ti or Ta). The inclusions of higher borides (with stoichiometry near MgB12 in the high pressure-manufactured magnesium diboride or near MgB7 in the hot-pressing-synthesized material) can effect critical current density: higher amount and finer dispersion of the above inclusions are observed in the materials with higher critical currents. Samples synthesized (at 4 GPa) from the MgB12 stoichiometric mixture of Mg and B that, according to the SEM microprobe analysis, contained MgB12 (more than 50 %) and MgO phases and, according to X-ray analysis, along with the above phases some amount of MgB2 demonstrated superconducting behavior. From high-pressure synthesized MgB2 blocks the first reluctance-type superconductive electromotor (1,3 kW) has been constructed and successfully tested.

  17. Cenozoic geological and plate tectonic evolution of SE Asia and the SW Pacific: computer-based reconstructions, model and animations

    NASA Astrophysics Data System (ADS)

    Hall, Robert

    2002-04-01

    A plate tectonic model for the Cenozoic development of the region of SE Asia and the SW Pacific is presented and its implications are discussed. The model is accompanied by computer animations in a variety of formats, which can be viewed on most desktop computers. GPS measurements and present seismicity illustrate the high rates of motions and tectonic complexity of the region, but provide little help in long-term reconstruction. Plate boundaries shifted rapidly in the Cenozoic. During convergence of the major plates, there were numerous important episodes of extension, forming ocean basins and causing subsidence within continental regions, probably driven by subduction. Within eastern Indonesia, New Guinea and the Melanesian arcs, there are multiple Cenozoic sutures, with very short histories compared to most well-known older orogenic belts. They preserve a record of major changes in tectonics, including subduction polarity reversals, elimination of volcanic arcs, changing plate boundaries and extension within an overall contractional setting. Rapid tectonic changes have occurred within periods of less than 5 Ma. Many events would be overlooked or ignored in older orogenic belts, even when evidence is preserved, because high resolution dating is required to identify them, and the inference of almost simultaneous contraction and extension seems contradictory. There were three important periods in regional development: at about 45, 25 and 5 Ma. At these times, plate boundaries and motions changed, probably because of major collision events. The 45 Ma plate reorganisation may be related to India-Asia collision, although some important intra-Pacific events, such as voluminous Eocene boninite magmatism, seem to be older and require other causes. Indentation of Asia by India modified the Asian continent, but there is little indication that India has been the driving force of tectonics in most of SE Asia. The most important Cenozoic plate boundary reorganisation was at

  18. Solar 'hot spots' are still hot

    NASA Technical Reports Server (NTRS)

    Bai, Taeil

    1990-01-01

    Longitude distributions of solar flares are not random but show evidence for active zones (or hot spots) where flares are concentrated. According to a previous study, two hot spots in the northern hemisphere, which rotate with a synodic period of about 26.72 days, produced the majority of major flares, during solar cycles 20 and 21. The more prominent of these two hot spots is found to be still active during the rising part of cycle 22, producing the majority of northern hemisphere major flares. The synodic rotation period of this hot spot is 26.727 + or - 0.007 days. There is also evidence for hot spots in the southern hemisphere. Two hot spots separated by 180 deg are found to rotate with a period of 29.407 days, with one of them having persisted in the same locations during cycles 19-22 and the other, during cycles 20-22.

  19. Peel-Off Characteristics at Interface between Base Film and Dielectrics with Spin-Coating Film Transfer and Hot-Pressing Technology

    NASA Astrophysics Data System (ADS)

    Kamei, Toshikazu; Sato, Norio; Kudou, Kazuhisa; Kawagoe, Masafumi; Adachi, Hideki; Machida, Katsuyuki

    2007-10-01

    This paper describes the peel-off characteristics of spin-coating film transfer and hot-pressing (STP) technology. STP technology is a new film-formation technology that enables the transfer of a dielectric on a base film onto a wafer by hot pressing. The base film is then peeled off at the interface between the base film and the dielectric. It is examined to control the peel force by the surface treatment of the base film of a fluoropolymer and STP process conditions. An apparatus for measuring peel force during peel off is also devised. The measurement results clarified that the magnitude of the normalized peel force ranges from about 2 to 3 N/cm for a 1-μm-thick dielectric, depending on the surface treatment and STP process conditions. The X-ray photoelectron spectroscopy spectrum of the surface of the base film after peel off indicated that peel off was carried out at the interface. Therefore, it is confirmed that STP technology enables the control of the characteristics of peel off.

  20. New 40Ar/39Ar age progression for the Louisville hot spot trail and implications for inter-hot spot motion

    NASA Astrophysics Data System (ADS)

    Koppers, Anthony A. P.; Gowen, Molly D.; Colwell, Lauren E.; Gee, Jeffrey S.; Lonsdale, Peter F.; Mahoney, John J.; Duncan, Robert A.

    2011-12-01

    hot spot motions, therefore provide a better fit to the new Louisville age data. The fit is particularly good for seamounts younger than 50 Ma, a period for which there is little predicted motion for the Louisville hot spot and little inter-hot spot motion with Hawaii. However, discrepancies in the Louisville age-distance record prior to 50 Ma indicate there is an extra source of inter-hot spot motion between Louisville and the other Pacific hot spots that was not corrected for in the global S04G model. Finally, based on six new 40Ar/39Ar age dates, the 169°W bend in the Louisville seamount trail seems to have formed at least 3 Myr before the formation of the Hawaiian-Emperor bend. The timing of the most acute parts of both bends thus appears to be asynchronous, which would require other processes (e.g., plume motions) than a global plate motion change between 50 and 47 Ma to explain these two observations.

  1. Comparison of two optical-density-based methods and a plate count method for estimation of growth parameters of Bacillus cereus.

    PubMed

    Biesta-Peters, Elisabeth G; Reij, Martine W; Joosten, Han; Gorris, Leon G M; Zwietering, Marcel H

    2010-03-01

    Quantitative microbiological models predicting proliferation of microorganisms relevant for food safety and/or food stability are useful tools to limit the need for generation of biological data through challenge testing and shelf-life testing. The use of these models requires quick and reliable methods for the generation of growth data and estimation of growth parameters. Growth parameter estimation can be achieved using methods based on plate counting and methods based on measuring the optical density. This research compares the plate count method with two optical density methods, namely, the 2-fold dilution (2FD) method and the relative rate to detection (RRD) method. For model organism Bacillus cereus F4810/72, the plate count method and both optical density methods gave comparable estimates for key growth parameters. Values for the maximum specific growth rate (mu(max)) derived by the 2FD method and by the RRD method were of the same order of magnitude, but some marked differences between the two approaches were apparent. Whereas the 2FD method allowed the derivation of values for lag time (lambda) from the data, this was not possible with the RRD method. However, the RRD method gave many more data points per experiment and also gave more data points close to the growth boundary. This research shows that all three proposed methods can be used for parameter estimation but that the choice of method depends on the objectives of the research.

  2. Freestanding GaN-based light-emitting diode membranes on Y3Al5O12:Ce3+ crystal phosphor plate for efficient white light emission

    NASA Astrophysics Data System (ADS)

    Feng, Lungang; Li, Yufeng; Xiong, Han; Wang, Shuai; Wang, Jiangteng; Ding, Wen; Zhang, Ye; Yun, Feng

    2016-08-01

    GaN-based light-emitting diode (LED) membranes were peeled from the substrate using electrochemical etching of the bottom sacrificial layer. The freestanding membranes were transferred onto a Y3Al5O12:Ce3+ (YAG:Ce3+) crystal phosphor plate to realize a compact white light source. Verified by the Raman test, the initial strain within the original GaN layers was greatly released after the exfoliation process, which induced alleviation of the quantum confined stark effect. The electroluminescence measurement of a blue LED membranes-on-YAG:Ce3+ plate-structured device was conducted exhibiting color coordinates and a correlated color temperature of (0.3367,0.4525) and 5450 K at 10 mA, respectively.

  3. An investigation of surface reconstruction from binocular disparity based on standard regularization theory: comparison between "membrane" and "thin-plate" potential energy models.

    PubMed

    Shiraiwa, Aya; Hayashi, Takefumi

    2011-08-01

    Visible surfaces of three-dimensional objects are reconstructed from two-dimensional retinal images in the early stages of human visual processing. In the computational model of surface reconstruction based on the standard regularization theory, an energy function is minimized. Two types of model have been proposed, called "membrane" and "thin-plate" after their function formulas, in which the first or the second derivative of depth information is used. In this study, the threshold of surface reconstruction from binocular disparity was investigated using a sparse random dot stereogram, and the predictive accuracy of these models was evaluated. It was found that the thin-plate model reconstructed surfaces more accurately than the membrane model and showed good agreement with experimental results. The likelihood that these models imitate human processing of visual information is discussed in terms of the size of receptive fields in the visual pathways of the human cortex.

  4. Practical automatic Arabic license plate recognition system

    NASA Astrophysics Data System (ADS)

    Mohammad, Khader; Agaian, Sos; Saleh, Hani

    2011-02-01

    Since 1970's, the need of an automatic license plate recognition system, sometimes referred as Automatic License Plate Recognition system, has been increasing. A license plate recognition system is an automatic system that is able to recognize a license plate number, extracted from image sensors. In specific, Automatic License Plate Recognition systems are being used in conjunction with various transportation systems in application areas such as law enforcement (e.g. speed limit enforcement) and commercial usages such as parking enforcement and automatic toll payment private and public entrances, border control, theft and vandalism control. Vehicle license plate recognition has been intensively studied in many countries. Due to the different types of license plates being used, the requirement of an automatic license plate recognition system is different for each country. [License plate detection using cluster run length smoothing algorithm ].Generally, an automatic license plate localization and recognition system is made up of three modules; license plate localization, character segmentation and optical character recognition modules. This paper presents an Arabic license plate recognition system that is insensitive to character size, font, shape and orientation with extremely high accuracy rate. The proposed system is based on a combination of enhancement, license plate localization, morphological processing, and feature vector extraction using the Haar transform. The performance of the system is fast due to classification of alphabet and numerals based on the license plate organization. Experimental results for license plates of two different Arab countries show an average of 99 % successful license plate localization and recognition in a total of more than 20 different images captured from a complex outdoor environment. The results run times takes less time compared to conventional and many states of art methods.

  5. Real-time thermal imaging of microwave accelerated metal-enhanced fluorescence (MAMEF) based assays on sapphire plates.

    PubMed

    Previte, Michael J R; Zhang, Yongxia; Aslan, Kadir; Geddes, Chris D

    2007-11-01

    In this paper, we describe an optical geometry that facilitates our further characterization of the temperature changes above silver island films (SiFs) on sapphire plates, when exposed to microwave radiation. Since sapphire transmits IR, we designed an optical scheme to capture real-time temperature images of a thin water film on sapphire plates with and without SiFs during the application of a short microwave pulse. Using this optical scheme, we can accurately determine the temperature profile of solvents in proximity to metal structures when exposed to microwave irradiation. We believe that this optical scheme will provide us with a basis for further studies in designing metal structures to further improve plasmonic-fluorescence clinical sensing applications, such as those used in microwave accelerated metal-enhanced fluorescence (MAMEF).

  6. A disposable, roll-to-roll hot-embossed inertial microfluidic device for size-based sorting of microbeads and cells.

    PubMed

    Wang, Xiao; Liedert, Christina; Liedert, Ralph; Papautsky, Ian

    2016-05-21

    Inertial microfluidics has been a highly active area of research in recent years for high-throughput focusing and sorting of synthetic and biological microparticles. However, existing inertial microfluidic devices always rely on microchannels with high-aspect-ratio geometries (channel width w < channel height h) and small cross-sections (w×h < 50 × 100 μm(2)). Such deep and small structures increase fabrication difficulty and can limit manufacturing by large-scale and high-throughput production approaches such as roll-to-roll (R2R) hot embossing. In this work, we present a novel inertial microfluidic device using only a simple and low-aspect-ratio (LAR) straight microchannel (w > h) to achieve size-based sorting of microparticles and cells. The simple LAR geometry of the device enables successful high-throughput fabrication using R2R hot embossing. With optimized flow conditions and channel dimensions, we demonstrate continuous sorting of a mixture of 15 μm and 10 μm diameter microbeads with >97% sorting efficiency using the low-cost and disposable R2R chip. We further demonstrate size-based sorting of bovine white blood cells, demonstrating the ability to process real cellular samples in our R2R chip. We envision that this R2R hot-embossed inertial microfluidic chip will serve as a powerful yet low-cost and disposable tool for size-based sorting of synthetic microparticles in industrial applications or cellular samples in cell biology research and clinical diagnostics.

  7. Ridge subduction sparked reorganization of the Pacific plate-mantle system 60-50 million years ago

    NASA Astrophysics Data System (ADS)

    Seton, Maria; Flament, Nicolas; Whittaker, Joanne; Müller, R. Dietmar; Gurnis, Michael; Bower, Dan J.

    2015-03-01

    A reorganization centered on the Pacific plate occurred ~53-47 million years ago. A "top-down" plate tectonic mechanism, complete subduction of the Izanagi plate, as opposed to a "bottom-up" mantle flow mechanism, has been proposed as the main driver. Verification based on marine geophysical observations is impossible as most ocean crust recording this event has been subducted. Using a forward modeling approach, which assimilates surface plate velocities and shallow thermal structure of slabs into mantle flow models, we show that complete Izanagi plate subduction and margin-wide slab detachment induced a major change in sub-Pacific mantle flow, from dominantly southward before 60 Ma to north-northeastward after 50 Ma. Our results agree with onshore geology, mantle tomography, and the inferred motion of the Hawaiian hot spot and are consistent with a plate tectonic process driving the rapid plate-mantle reorganization in the Pacific hemisphere between 60 and 50 Ma. This reorganization is reflected in tectonic changes in the Pacific and surrounding ocean basins.

  8. Plate motion and deformation

    SciTech Connect

    Minster, B.; Prescott, W.; Royden, L.

    1991-02-01

    Our goal is to understand the motions of the plates, the deformation along their boundaries and within their interiors, and the processes that control these tectonic phenomena. In the broadest terms, we must strive to understand the relationships of regional and local deformation to flow in the upper mantle and the rheological, thermal and density structure of the lithosphere. The essential data sets which we require to reach our goal consist of maps of current strain rates at the earth's surface and the distribution of integrated deformation through time as recorded in the geologic record. Our success will depend on the effective synthesis of crustal kinematics with a variety of other geological and geophysical data, within a quantitative theoretical framework describing processes in the earth's interior. Only in this way can we relate the snapshot of current motions and earth structure provided by geodetic and geophysical data with long-term processes operating on the time scales relevant to most geological processes. The wide-spread use of space-based techniques, coupled with traditional geological and geophysical data, promises a revolution in our understanding of the kinematics and dynamics of plate motions over a broad range of spatial and temporal scales and in a variety of geologic settings. The space-based techniques that best address problems in plate motion and deformation are precise space-geodetic positioning -- on land and on the seafloor -- and satellite acquisition of detailed altimetric and remote sensing data in oceanic and continental areas. The overall science objectives for the NASA Solid Earth Science plan for the 1990's, are to Understand the motion and deformation of the lithosphere within and across plate boundaries'', and to understand the dynamics of the mantle, the structure and evolution of the lithosphere, and the landforms that result from local and regional deformation. 57 refs., 7 figs., 2 tabs.

  9. Structural health monitoring method based on the entropy of an ultrasonic sensor network for a plate-like structure

    NASA Astrophysics Data System (ADS)

    Rojas, Erick; Baltazar, Arturo

    2015-03-01

    Piezoelectric ultrasonic sensors used to propagate guided waves can potentially be implemented to inspect large areas in engineering structures. However, the inherent dispersion and noise of the guided acoustic signals, multiple echoes in the plate as well as a lack of an approximate or exact model limits their use as a continuous structural health monitoring system. In this work, the implementation of a network of piezoelectric sensors randomly placed on a plate-like structure to detect and locate artificial damage is studied. A sensor network of randomly located 1MHz transducers working in a pitch-catch configuration was set on an aluminum thin plate 1.9 mm in thickness. Signals were analyzed in time-scale domain by the continuous wavelet transform. The objectives in this work were twofold, first to develop a damage index using the entropy of the ultrasonic waves generated by a sensor network; and second to implement time of arrival (TOA) and time-difference of arrival (TDOA) algorithms on the gathered signals for damage location of an artificial circular discontinuity. Our preliminary test results show that the proposed methodology provides sufficient information for damage detection which, once combined with the TOA and TDOA algorithms, allows localization of the damage.

  10. Solvent accessible surface area-based hot-spot detection methods for protein-protein and protein-nucleic acid interfaces.

    PubMed

    Munteanu, Cristian R; Pimenta, António C; Fernandez-Lozano, Carlos; Melo, André; Cordeiro, Maria N D S; Moreira, Irina S

    2015-05-26

    Due to the importance of hot-spots (HS) detection and the efficiency of computational methodologies, several HS detecting approaches have been developed. The current paper presents new models to predict HS for protein-protein and protein-nucleic acid interactions with better statistics compared with the ones currently reported in literature. These models are based on solvent accessible surface area (SASA) and genetic conservation features subjected to simple Bayes networks (protein-protein systems) and a more complex multi-objective genetic algorithm-support vector machine algorithms (protein-nucleic acid systems). The best models for these interactions have been implemented in two free Web tools.

  11. Reflection-Zone-Plate Antenna

    NASA Technical Reports Server (NTRS)

    Franke, John M.; Leighty, Bradley D.

    1989-01-01

    Microwave antenna, based on reflection holography, designed and tested. Modified to produce arbitrary beam patterns by controlling relief pattern. Antenna planar or contoured to supporting structure. Low off-axis radar cross section at frequencies removed from operational frequency. Interference pattern produced by spherical wave intersecting plane wave consists of concentric circles similar to Newton's rings. Pattern identical to Fresnel zone plate, which has lens properties. Plane wave incident on hologram, or zone plate, focused to point.

  12. Application of Wave Propagation and Vibration-based Structural Health Monitoring Techniques to Friction Stir Welded Plate and Sandwich Honeycomb Panel

    NASA Astrophysics Data System (ADS)

    Sundararaman, S.; White, J. R.; Adams, D. E.; Jata, K. V.

    2007-03-01

    Wave propagation and vibration-based structural health monitoring methodologies are presented to detect, locate and quantify dent/crack, thermal debond, and corrosion damage in a solid aluminum friction stir weld plate and a sandwich honeycomb thermal protection panel. A wave propagation based method can identify small defects because propagating waves typically consist of small wavelengths while a vibration-based scheme is better equipped to quantify damage over wide areas of large structures. Near-real time online diagnostics is achieved by using localized sensing (wave propagation) and distributed sensing (vibration-based) in an active measurement array. Sensor/actuator arrays have been developed to implement these techniques and portable health management systems have been developed based on the combination of damage detection algorithms, active sensing, and graphical user interfaces. Propagating waves are shown to have a heightened sensitivity to damage located at the anti-nodes of a friction stir wed plate forced by low frequency environmental vibrations. Measurement of the input forcing in the vibration-based method is shown to enable damage quantification.

  13. Hot deformation behaviour of alloys for applications at elevated temperatures

    NASA Astrophysics Data System (ADS)

    Voyzelle, Benoit

    The present study investigated the deformation behaviour, microstructure evolution and fracture behaviour under hot working conditions of alloys designed for elevated-temperature applications. For this purpose, iron-aluminum and titanium-aluminum alloys were selected and their compositions are: Fe-8.5wt%Al-5.5Cr-2.0Mo-0.2Zr-0.03C, Fe-16.5Al-5.5Cr-1.0Nb-0.05C and Ti-33.3Al-2.8Mn-4.8Nb. These alloys were tested in the as-cast condition and in the form of hot-rolled + annealed plate for the iron-aluminum alloys and in the HIP'ed condition for the titanium-aluminum alloy. Isothermal compression tests were carried out with a Gleeble 2000 over a range of temperatures from 800 to 1250°C and constant strain rates from 10-3 to 10 s-1. In general, the flow curves are marked by a peak stress and softening which decline as temperature rises, and a flow stress which diminishes with rise in temperature and decrease in strain rate. The flow behaviour at peak stress (sigmap) and 0.5 true strain of these materials was described well by the Zener-Hollomon parameter Z=3˙exp /RTQHW , where Z=K3sinha sn . A numerical curve-fitting method was used to yield values of the following parameters: (i) stress exponent, n and (ii) activation energy, QHW . The dynamic material modeling approach was performed to extract from hot compression data: (i) the strain rate sensitivity parameter, m, (ii) the efficiency of power dissipation, eta, and (iii) the instability parameter, xi. The microstructure evolution and fracture behaviour were assessed using optical and electron microscopy. The deformation processes occuring were determined by correlation of the sigma-epsilon curves, m and microstructural observations. The resulting deformation map indicates that at lower temperatures and higher strain rates, the dominant restoration occurs by dynamic recovery, while at lower strain rates and higher temperatures dynamic recrystallization is the operative mode. At the highest temperatures, dynamic

  14. Sputtering and ion plating

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The proceedings of a conference on sputtering and ion plating are presented. Subjects discussed are: (1) concepts and applications of ion plating, (2) sputtering for deposition of solid film lubricants, (3) commercial ion plating equipment, (4) industrial potential for ion plating and sputtering, and (5) fundamentals of RF and DC sputtering.

  15. Development of expert systems for the design of a hot-forging process based on material workability

    NASA Astrophysics Data System (ADS)

    Ravi, R.; Prasad, Y. V. R. K.; Sarma, V. V. S.

    2003-12-01

    Most of the time (and cost) involved in planning hot forging process is related to activities strongly dependent on human expertise, intuition, and creativity, and also to iterative procedure involving extensive experimental work. In this paper, the development of an expert system for forging process design, which emphasizes materials’ workability, is discussed. Details of the forging process design expert system, its basic modules, design and implementation details, and deliverables are explained. The system uses the vast database available on the hot workability of more than 200 technologically important materials and the knowledge acquired from a materials’ expert. The C Language Integrated Production System (CLIPS) has been adopted to develop this expert system. The expert system can address three types of functions, namely, forging process design, materials information system, and forging defect analysis. The expert system will aid and prompt a novice engineer in designing a forging process by providing accurate information of the process parameters, lubricants, type of machine, die material, and type of process (isothermal versus non-isothermal) for a given material with a known specification or code and prior history.

  16. Hot deformation behavior of uniform fine-grained GH4720Li alloy based on its processing map

    NASA Astrophysics Data System (ADS)

    Yu, Qiu-ying; Yao, Zhi-hao; Dong, Jian-xin

    2016-01-01

    The hot deformation behavior of uniform fine-grained GH4720Li alloy was studied in the temperature range from 1040 to 1130°C and the strain-rate range from 0.005 to 0.5 s-1 using hot compression testing. Processing maps were constructed on the basis of compression data and a dynamic materials model. Considerable flow softening associated with superplasticity was observed at strain rates of 0.01 s-1 or lower. According to the processing map and observations of the microstructure, the uniform fine-grained microstructure remains intact at 1100°C or lower because of easily activated dynamic recrystallization (DRX), whereas obvious grain growth is observed at 1130°C. Metallurgical instabilities in the form of non-uniform microstructures under higher and lower Zener-Hollomon parameters are induced by local plastic flow and primary γ' local faster dissolution, respectively. The optimum processing conditions at all of the investigated strains are proposed as 1090-1130°C with 0.08-0.5 s-1 and 0.005-0.008 s-1 and 1040-1085°C with 0.005-0.06 s-1.

  17. Size-dependent dynamic pull-in analysis of geometric non-linear micro-plates based on the modified couple stress theory

    NASA Astrophysics Data System (ADS)

    Askari, Amir R.; Tahani, Masoud

    2017-02-01

    This paper focuses on the size-dependent dynamic pull-in instability in rectangular micro-plates actuated by step-input DC voltage. The present model accounts for the effects of in-plane displacements and their non-classical higher-order boundary conditions, von Kármán geometric non-linearity, non-classical couple stress components and the inherent non-linearity of distributed electrostatic pressure on the micro-plate motion. The governing equations of motion, which are clearly derived using Hamilton's principle, are solved through a novel computationally very efficient Galerkin-based reduced order model (ROM) in which all higher-order non-classical boundary conditions are completely satisfied. The present findings are compared and successfully validated by available results in the literature as well as those obtained by three-dimensional finite element simulations carried out using COMSOL Multyphysics. A detailed parametric study is also conducted to illustrate the effects of in-plane displacements, plate aspect ratio, couple stress components and geometric non-linearity on the dynamic instability threshold of the system.

  18. Hot money

    NASA Astrophysics Data System (ADS)

    Bennett, Gordon; Sleeman, Richard

    1994-10-01

    British Aerospace has established an analysis service for UK Police and Customs authorities based on its CONDOR contraband detection system. The service has been successfully used to detect drug traces in cars, buildings and on bank notes. Recent legislation in the UK allows for the confiscation of the proceeds of drug related crime. The service has been used to assist in the confiscation of large sums of money, presumably drug related, being taken out of the country. A range of drugs has been detected on suspect money, whereas money in general circulation, obtained from the Bank of England, has been shown to be free from contamination. The way in which samples are collected and analyzed, and typical results are discussed.

  19. Establishment of a fully automated microtiter plate-based system for suspension cell culture and its application for enhanced process optimization.

    PubMed

    Markert, Sven; Joeris, Klaus

    2017-01-01

    We developed an automated microtiter plate (MTP)-based system for suspension cell culture to meet the increased demands for miniaturized high throughput applications in biopharmaceutical process development. The generic system is based on off-the-shelf commercial laboratory automation equipment and is able to utilize MTPs of different configurations (6-24 wells per plate) in orbital shaken mode. The shaking conditions were optimized by Computational Fluid Dynamics simulations. The fully automated system handles plate transport, seeding and feeding of cells, daily sampling, and preparation of analytical assays. The integration of all required analytical instrumentation into the system enables a hands-off operation which prevents bottlenecks in sample processing. The modular set-up makes the system flexible and adaptable for a continuous extension of analytical parameters and add-on components. The system proved suitable as screening tool for process development by verifying the comparability of results for the MTP-based system and bioreactors regarding profiles of viable cell density, lactate, and product concentration of CHO cell lines. These studies confirmed that 6 well MTPs as well as 24 deepwell MTPs were predictive for a scale up to a 1000 L stirred tank reactor (scale factor 1:200,000). Applying the established cell culture system for automated media blend screening in late stage development, a 22% increase in product yield was achieved in comparison to the reference process. The predicted product increase was subsequently confirmed in 2 L bioreactors. Thus, we demonstrated the feasibility of the automated MTP-based cell culture system for enhanced screening and optimization applications in process development and identified further application areas such as process robustness. The system offers a great potential to accelerate time-to-market for new biopharmaceuticals. Biotechnol. Bioeng. 2017;114: 113-121. © 2016 Wiley Periodicals, Inc.

  20. Three-dimensional model of plate geometry and velocity model for Nankai Trough seismogenic zone based on results from structural studies

    NASA Astrophysics Data System (ADS)

    Nakanishi, A.; Shimomura, N.; Kodaira, S.; Obana, K.; Takahashi, T.; Yamamoto, Y.; Yamashita, M.; Takahashi, N.; Kaneda, Y.

    2012-12-01

    In the Nankai Trough subduction seismogenic zone, the Nankai and Tonankai earthquakes had often occurred simultaneously, and caused a great event. In order to reduce a great deal of damage to coastal area from both strong ground motion and tsunami generation, it is necessary to understand rupture synchronization and segmentation of the Nankai megathrust earthquake. For a precise estimate of the rupture zone of the Nankai megathrust event based on the knowledge of realistic earthquake cycle and variation of magnitude, it is important to know the geometry and property of the plate boundary of the subduction seismogenic zone. To improve a physical model of the Nankai Trough seismogenic zone, the large-scale high-resolution wide-angle and reflection (MCS) seismic study, and long-term observation has been conducted since 2008. Marine active source seismic data have been acquired along grid two-dimensional profiles having the total length of ~800km every year. A three-dimensional seismic tomography using active and passive seismic data observed both land and ocean bottom stations have been also performed. From those data, we found that several strong lateral variations of the subducting Philippine Sea plate and overriding plate corresponding to margins of coseismic rupture zone of historical large event occurred along the Nankai Trough. Particularly a possible prominent reflector for the forearc Moho is recently imaged in the offshore side in the Kii channel at the depth of ~18km which is shallower than those of other area along the Nankai Trough. Such a drastic variation of the overriding plate might be related to the existence of the segmentation of the Nankai megathrust earthquake. Based on our results derived from seismic studies, we have tried to make a geometrical model of the Philippine Sea plate and a three-dimensional velocity structure model of the Nankai Trough seismogenic zone. In this presentation, we will summarize major results of out seismic studies, and