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Sample records for experimental parameter study

  1. An experimental study on effect of process parameters in deep ...

    African Journals Online (AJOL)

    The effects of various deep drawing process parameters were determined by experimental study with the use of Taguchi fractional factorial design and analysis of variance for AA6111 Aluminum alloy. The optimum process parameters were determined based on their influence on the thickness variation at different regions ...

  2. Experimental Studies of the Transport Parameters of Warm Dense Matter

    Energy Technology Data Exchange (ETDEWEB)

    Chouffani, Khalid [Idaho State Univ., Pocatello, ID (United States)

    2014-12-01

    There is a need to establish fundamental properties of matter and energy under extreme physical conditions. Although high energy density physics (HEDP) research spans a wide range of plasma conditions, there is one unifying regime that is of particular importance and complexity: that of warm dense matter, the transitional state between solid state condensed matter and energetic plasmas. Most laboratory experimental conditions, including inertial confinement implosion, fall into this regime. Because all aspects of laboratory-created high-energy-density plasmas transition through the warm dense matter regime, understanding the fundamental properties to determine how matter and energy interact in this regime is an important aspect of major research efforts in HEDP. Improved understanding of warm dense matter would have significant and wide-ranging impact on HEDP science, from helping to explain wire initiation studies on the Sandia Z machine to increasing the predictive power of inertial confinement fusion modeling. The central goal or objective of our proposed research is to experimentally determine the electrical resistivity, temperature, density, and average ionization state of a variety of materials in the warm dense matter regime, without the use of theoretical calculations. Since the lack of an accurate energy of state (EOS) model is primarily due to the lack of experimental data, we propose an experimental study of the transport coefficients of warm dense matter.

  3. Experimental constraints on transport from dimensionless parameter scaling studies

    International Nuclear Information System (INIS)

    Petty, C.C.; Luce, T.C.; Baker, D.R.

    1998-02-01

    The scalings of heat transport with safety factor (q), normalized collisionality (v), plasma beta (β), and relative gyroradius (ρ*) have been measured on the DIII-D tokamak. The measured ρ* β and v scalings of heat transport indicate that E x B transport from drive wave turbulence is a plausible basis for anomalous transport. For high confinement (H) mode plasmas where the safety factor was varied at fixed magnetic shear, the effective (or one-fluid) thermal diffusivity was found to scale like χ eff ∝ q 2.3±0.64 , with the ion and electron fluids having the same q scaling to within the experimental errors except near the plasma edge. The scaling of the thermal confinement time with safety factor was in good agreement with this local transport dependence, τ th ∝ q -2.42±0.31 ; however, when the magnetic shear was allowed to vary to keep q 0 fixed during the (edge) safety factor scan, a weaker global dependence was observed, τ th ∝ q 95 -1.43±0.23 . This weaker dependence was mainly due to the change in the local value of q between the two types of scans. The combined ρ*, β, v and q scalings of heat transport for H-mode plasmas on DIII-D reproduce the empirical confinement scaling using physical (dimensionless) parameters with the exception of weaker power degradation

  4. Experimental constraints on transport from dimensionless parameter scaling studies

    International Nuclear Information System (INIS)

    Petty, C.C.; Luce, T.C.; Baker, D.R.; Ballet, B.; Carlstrom, T.N.; Cordey, J.G.; DeBoo, J.C.; Gohil, P.; Groebner, R.J.; Rice, B.W.; Thomas, D.M.; Wade, M.R.; Waltz, R.E.

    1998-01-01

    The scalings of heat transport with safety factor (q), normalized collisionality (ν), plasma beta (β), and relative gyroradius (ρ * ) have been measured on the DIII-D tokamak [Fusion Technol. 8, 441 (1985)]. The measured ρ * , β and ν scalings of heat transport indicate that ExB transport from drift wave turbulence is a plausible basis for anomalous transport. For high confinement (H) mode plasmas where the safety factor was varied at fixed magnetic shear, the effective (or one-fluid) thermal diffusivity was found to scale like χ eff ∝q 2.3±0.64 , with the ion and electron fluids having the same q scaling to within the experimental errors except near the plasma edge. The scaling of the thermal confinement time with safety factor was in good agreement with this local transport dependence, τ th ∝q -2.42±0.31 ; however, when the magnetic shear was allowed to vary to keep q 0 fixed during the (edge) safety factor scan, a weaker global dependence was observed, τ th ∝q 95 -1.43±0.23 . This weaker dependence was mainly due to the change in the local value of q between the two types of scans. The combined ρ * , β , ν and q scalings of heat transport for H-mode plasmas on DIII-D reproduce the empirical confinement scaling using physical (dimensional) parameters with the exception of weaker power degradation. copyright 1998 American Institute of Physics

  5. A systematic study of distribution characters of infiltration parameters in an experimental basin by nuclear methods

    International Nuclear Information System (INIS)

    Gu Weizu; Lu Jieju; Lu Mingjiang; Chen Tingyang

    1988-01-01

    A case study of spatial variability of Philip's infiltration parameters was carried out in a small experimental catchment with an area of 0.8 ha by nuclear monitoring methods. Relationships between sorptivity S, parameter A and the average initial soil water content within 0.5 m depth of soil profiles over the catchment have been plotted. A watershed infiltration parameter distribution curve is set up and fitted approximately by f/F=1-(1-S/S M ) n . The parameters of composite infiltration response related to whole catchment are suggested. The author has studied it on an experimental basin by combined method of nuclear technology and micro-geomorphic analysis. The results are satisfactory. (author). 6 refs, 11 figs, 2 tabs

  6. The reaction between iodine and organic coatings under severe PWR accident conditions. An experimental parameter study

    Energy Technology Data Exchange (ETDEWEB)

    Hellmann, S; Funke, F; Greger, G U; Bleier, A; Morell, W [Siemens AG, Power Generation Group, Erlangen (Germany)

    1996-12-01

    An extensive experimental parameter study was performed on the deposition and on the resuspension kinetics in the reaction system iodine/organically coated surfaces. Both reactions in the gas phase and in the liquid phase were investigated and kinetic rate constants suitable for modelling were derived. Previous experimental studies on the reaction of iodine with organic coated surfaces were mostly limited to temperatures below 100{sup o}C. Thus, this parameter study aims at filling a gap and providing kinetic data on heterogeneous reactions with organic surfaces in the accident-relevant temperature range of 100-160{sup o}C. Two types of laboratory experiments carried out at Siemens/KWU using coatings representative for German power plants (epoxy-tape paint), namely gas phase tests and liquid phase tests. (author) 6 figs., 6 tabs., 5 refs.

  7. Impact parameter sensitive study of inner-shell atomic processes in the experimental storage ring

    Science.gov (United States)

    Gumberidze, A.; Kozhuharov, C.; Zhang, R. T.; Trotsenko, S.; Kozhedub, Y. S.; DuBois, R. D.; Beyer, H. F.; Blumenhagen, K.-H.; Brandau, C.; Bräuning-Demian, A.; Chen, W.; Forstner, O.; Gao, B.; Gassner, T.; Grisenti, R. E.; Hagmann, S.; Hillenbrand, P.-M.; Indelicato, P.; Kumar, A.; Lestinsky, M.; Litvinov, Yu. A.; Petridis, N.; Schury, D.; Spillmann, U.; Trageser, C.; Trassinelli, M.; Tu, X.; Stöhlker, Th.

    2017-10-01

    In this work, we present a pilot experiment in the experimental storage ring (ESR) at GSI devoted to impact parameter sensitive studies of inner shell atomic processes for low-energy (heavy-) ion-atom collisions. The experiment was performed with bare and He-like xenon ions (Xe54+, Xe52+) colliding with neutral xenon gas atoms, resulting in a symmetric collision system. This choice of the projectile charge states was made in order to compare the effect of a filled K-shell with the empty one. The projectile and target X-rays have been measured at different observation angles for all impact parameters as well as for the impact parameter range of ∼35-70 fm.

  8. An experimental study of symmetric and asymmetric peak-fitting parameters for alpha-particle spectrometry

    International Nuclear Information System (INIS)

    Martin Sanchez, A.; Vera Tome, F.; Caceres Marzal, D.; Bland, C.J.

    1994-01-01

    A pulse-height spectrum of alpha-particle emissions at discrete energies can be fitted by the peak-shape functions generated by combining asymmetric truncated exponential functions with a symmetric Gaussian distribution. These functions have been applied successfully by several workers. A correlation was previously found between the variance of the symmetric Gaussian portion of the fitting function, and the parameter characterising the principal exponential tailing function. The results of a more detailed experimental study are reported, which involve varying the angle and the distance between the source and the detector. This analysis shows that the parameters of the symmetric and asymmetric parts of the fitted functions seem to depend on either the detector or the source. These parameters are influenced by the energy loss suffered by the alpha-particles as well as by the efficiency of charge collection in the solid-state detector. (orig.)

  9. Experimental design for estimating parameters of rate-limited mass transfer: Analysis of stream tracer studies

    Science.gov (United States)

    Wagner, Brian J.; Harvey, Judson W.

    1997-01-01

    Tracer experiments are valuable tools for analyzing the transport characteristics of streams and their interactions with shallow groundwater. The focus of this work is the design of tracer studies in high-gradient stream systems subject to advection, dispersion, groundwater inflow, and exchange between the active channel and zones in surface or subsurface water where flow is stagnant or slow moving. We present a methodology for (1) evaluating and comparing alternative stream tracer experiment designs and (2) identifying those combinations of stream transport properties that pose limitations to parameter estimation and therefore a challenge to tracer test design. The methodology uses the concept of global parameter uncertainty analysis, which couples solute transport simulation with parameter uncertainty analysis in a Monte Carlo framework. Two general conclusions resulted from this work. First, the solute injection and sampling strategy has an important effect on the reliability of transport parameter estimates. We found that constant injection with sampling through concentration rise, plateau, and fall provided considerably more reliable parameter estimates than a pulse injection across the spectrum of transport scenarios likely encountered in high-gradient streams. Second, for a given tracer test design, the uncertainties in mass transfer and storage-zone parameter estimates are strongly dependent on the experimental Damkohler number, DaI, which is a dimensionless combination of the rates of exchange between the stream and storage zones, the stream-water velocity, and the stream reach length of the experiment. Parameter uncertainties are lowest at DaI values on the order of 1.0. When DaI values are much less than 1.0 (owing to high velocity, long exchange timescale, and/or short reach length), parameter uncertainties are high because only a small amount of tracer interacts with storage zones in the reach. For the opposite conditions (DaI ≫ 1.0), solute

  10. Experimental study on characteristics of interfacial parameter distribution for upward bubbly flow in inclined tube

    International Nuclear Information System (INIS)

    Xing Dianchuan; Yan Changqi; Sun Licheng; Liu Jingyu

    2013-01-01

    Experimental study on characteristics of interfacial parameter distribution for air-water bubbly flow in an inclined circular tube was performed by using the double sensor probe method. Parameters including radial distributions of local void fraction, bubble passing frequency, interfacial area concentration and bubble equivalent diameter were measured using the probe. The inner diameter of test section is 50 mm, and the liquid superficial velocity is 0.144 m/s, with the gas superficial velocity ranging from 0 to 0.054 m/is. The results show that bubbles obviously move toward the upper wall and congregate. The local interfacial area concentration, bubble passing frequency and void fraction have similar radial distribution profiles. Different from the vertical condition, for a cross-sectional area of the test section, the peak value near the upper side increases, while decreases or even disappears near the underside. The local parameter increases as the radial positions change from lower to upper location, and the increased slope becomes larger as the inclination angles increase. The equivalent bubble diameter doesn't vary with radial position, superficial gas velocity and inclination angle, and bubble aggregation and breaking up nearly doesn't occur. The mechanism of effects of inclination on local parameter distribution for bubbly flow is explained by analyzing the transverse force governing the bubble motion. (authors)

  11. An Experimental Study of the Local Parameters of a Damaged Cantilever

    DEFF Research Database (Denmark)

    Rytter, A.; Brincker, Rune; Kirkegaard, Poul Henning

    of results from experimental tests with six hollow section steel cantilevers containing a fatigue crack introduced from a narrow laser cut slot. The modal parameters have been identified for different size and location of a crack. The modal parameters have been estimated by mean of frequency domain and time...

  12. An Experimental Study of the Modal Parameters of a Damaged Cantilever

    DEFF Research Database (Denmark)

    Rytter, A.; Brincker, Rune; Kirkegaard, Poul Henning

    of results from experimental tests with six hollow section steel cantilevers containing a fatigue crack introduced from a narrow laser cut slot. The modal parameters have been identified for different size and location of a crack. The modal parameters have been estimated by mean of frequency domain and time...

  13. Experimental study of dual fuel engine performance using variable LPG composition and engine parameters

    International Nuclear Information System (INIS)

    Elnajjar, Emad; Selim, Mohamed Y.E.; Hamdan, Mohammad O.

    2013-01-01

    Highlights: • The effect of using variable LPG is studied. • Five fuels with propane to butane % volume ratio are: 100-70-55-25-0. • 100% Propane composition shows the highest noise levels with similar performance. • At 45° BTDC injection timing 55% Propane LPG the only fuel experience knocking. • LPG fuels gave similar engine performance, with differences in levels of noise. - Abstract: The present work investigates experimentally the effect of LPG fuel with different composition and engine parameters on the performance of a dual compression engine. Five different blends of LPG fuels are used with Propane to Butane volume ratio of 100:0, 70:30, 55:45, 25:75, and 0:100. A single cylinder, naturally aspirated, four strokes, indirectly injected, water cooled modified Ricardo E6 engine, is used in this study. The study is carried out by measuring the cylinder pressure, engine load, engine speed, crank angle, and the fuel’s flow rate. The engine performance under variable LPG fuel composition, engine load, pilot fuel injection timing, compression ratio, pilot fuel mass and engine speed, are estimated by comparing the following engine parameters: the cylinder maximum pressure, the indicated mean effective pressure, the maximum rate of pressure rise, and the thermal efficiency. The experimental data indicates that the engine parameters are playing a major role on the engine’s performance. Different LPG fuel composition did not show a major effect on the engine efficiency but directly impacted the levels of generated combustion noise

  14. A critical experimental study of integral physics parameters in simulated LMFBR meltdown cores

    International Nuclear Information System (INIS)

    Bhattacharyya, S.K.; Wade, D.C.; Bucher, R.G.; Smith, D.M.; McKnight, R.D.; Lesage, L.G.

    1978-01-01

    Integral physics parameters of several representative, idealized meltdown LMFBR configurations were measured in mockup critical assemblies on the ZPR-9 reactor at Argonne National Laboratory. The experiments were designed to provide data for the validation of analytical methods used in the neutronics part of LMFBR accident analysis. Large core distortions were introduced in these experiments (involving 18.5% core volume) and the reactivity worths of configuration changes were determined. The neutronics parameters measured in the various configurations showed large changes upon core distortion. Both diffusion theory and transport theory methods were shown to mispredict the experimental configuration eigenvalues. In addition, diffusion theory methods were shown to result in a non-conservative misprediction of the experimental configuration change worths. (author)

  15. Experimental studies of parameters affecting the heat generation in friction stir welding process

    Directory of Open Access Journals (Sweden)

    Mijajlović Miroslav M.

    2012-01-01

    Full Text Available Heat generation is a complex process of transformation of a specific type of energy into heat. During friction stir welding, one part of mechanical energy delivered to the welding tool is consumed in the welding process, another is used for deformational processes etc., and the rest of the energy is transformed into heat. The analytical procedure for the estimation of heat generated during friction stir welding is very complex because it includes a significant number of variables and parameters, and many of them cannot be fully mathematically explained. Because of that, the analytical model for the estimation of heat generated during friction stir welding defines variables and parameters that dominantly affect heat generation. These parameters are numerous and some of them, e. g. loads, friction coefficient, torque, temperature, are estimated experimentally. Due to the complex geometry of the friction stir welding process and requirements of the measuring equipment, adequate measuring configurations and specific constructional solutions that provide adequate measuring positions are necessary. This paper gives an overview of the process of heat generation during friction stir welding, the most influencing parameters on heat generation, constructional solutions for the measuring equipment needed for these experimental researches and examples of measured values.

  16. Design Parameters of Vortex Pumps: A Meta-Analysis of Experimental Studies

    Directory of Open Access Journals (Sweden)

    Angela Gerlach

    2017-01-01

    Full Text Available Vortex pumps can impel solid-containing fluids and are therefore widely applied, from wastewater transport to the food industry. Despite constant efforts to improve vortex pumps, however, they have remained relatively inefficient compared to conventional centrifugal pumps. To find an optimized design of vortex pumps, this paper provides a systematic analysis on experimental studies that investigated how variations in geometric parameters influence vortex pump characteristics, in particular the pump head, the pressure coefficient and the efficiency for best point operation. To this end, an extensive literature search was conducted, and eighteen articles with 53 primary investigations were identified and meta-integrated. This showed that it is not yet clarified how vortex pumps operate. Two different assumptions of the underlying operating principle of a vortex pump lead to diverging design principles. From the results of this meta-analysis, we deduce recommendations for a more efficient design of a vortex pump and emphasize further aspects on the underlying operating principle of a vortex pump.

  17. Arsenic mobilization in an oxidizing alkaline groundwater: Experimental studies, comparison and optimization of geochemical modeling parameters

    International Nuclear Information System (INIS)

    Hafeznezami, Saeedreza; Lam, Jacquelyn R.; Xiang, Yang; Reynolds, Matthew D.; Davis, James A.; Lin, Tiffany; Jay, Jennifer A.

    2016-01-01

    Arsenic (As) mobilization and contamination of groundwater affects millions of people worldwide. Progress in developing effective in-situ remediation schemes requires the incorporation of data from laboratory experiments and field samples into calibrated geochemical models. In an oxidizing aquifer where leaching of high pH industrial waste from unlined surface impoundments led to mobilization of naturally occurring As up to 2 mg L −1 , sequential extractions of solid phase As as well as, batch sediment microcosm experiments were conducted to understand As partitioning and solid-phase sorptive and buffering capacity. These data were combined with field data to create a series of geochemical models of the system with modeling programs PHREEQC and FITEQL. Different surface complexation modeling approaches, including component additivity (CA), generalized composite (GC), and a hybrid method were developed, compared and fitted to data from batch acidification experiments to simulate potential remediation scenarios. Several parameters strongly influence the concentration of dissolved As including pH, presence of competing ions (particularly phosphate) and the number of available sorption sites on the aquifer solids. Lowering the pH of groundwater to 7 was found to have a variable, but limited impact (<63%) on decreasing the concentration of dissolved As. The models indicate that in addition to lowering pH, decreasing the concentration of dissolved phosphate and/or increasing the number of available sorption sites could significantly decrease the As solubility to levels below 10 μg L −1 . The hybrid and GC modeling results fit the experimental data well (NRMSE<10%) with reasonable effort and can be implemented in further studies for validation. - Highlights: • Samples were collected from an oxidizing aquifer where high pH waste has led to mobilization of naturally occurring As. • Three surface complexation modeling approaches were used in modeling adsorption

  18. The reaction between iodine and silver under severe PWR accident conditions. An experimental parameter study

    Energy Technology Data Exchange (ETDEWEB)

    Funke, F; Greger, G U; Bleier, A; Hellmann, S; Morell, W [Siemens AG, Power Generation Group, Erlangen (Germany)

    1996-12-01

    An extensive experimental parameter study was performed on the kinetics in the reaction system I{sub 2}/Ag and I{sup -}/Ag in a laboratory-scale apparatus.Starting with I{sub 2} or I{sup -} solutions and silver powder suspensions, the decrease of soluted I{sub 2} or I{sup -}, respectively, due to fixation on the silver particles, was monitored as function of time using the radioactive tracer I-131. The measured data were analyzed using a model of first order kinetics with respect to the iodine concentration. However, the analysis using first order kinetics had to be performed separately in an early, fast reaction phase and in a late, slow reaction phase. The reason for this unexpected behaviour was not identified. Thus, rate constant, two for each test, were deduced from 14 I{sub 2}/Ag main tests and from 36 I{sup -}/Ag tests. No dependencies of the rate constants were found on the parameters temperature, initial iodine concentration, presence of boric acid, type of silver educt, and pretreatment of the silver educt prior to the tests. However, the stirring of the reaction solution generally enhanced the kinetics highlighting the importance of mass transfer. The I{sup -}/Ag reaction proceeded only if there was no inertization of the reaction solution by sparging with nitrogen. The temperature-independent rate constant for the early, fast I{sub 2}/Ag reaction phase is 2E-5 m/s. However, a smaller rate constant of 6E-6 m/s is recommended for use in source term calculations with IMPAIR, which already contains a first order model. Analogously, the temperature-independent I{sup -}/Ag reaction rate constant is 8E-6 m/s in an early, fast reaction phase. For use in source term calculations, a smaller rate constant of 2E-6 m/s is recommended. The lower bound of the I{sup -}/Ag rate constant was 3E-8 m/s which could be used in very conservative source term calculations. (author) 20 figs., 6 tabs., 15 refs.

  19. An Empirical Study of Parameter Estimation for Stated Preference Experimental Design

    Directory of Open Access Journals (Sweden)

    Fei Yang

    2014-01-01

    Full Text Available The stated preference experimental design can affect the reliability of the parameters estimation in discrete choice model. Some scholars have proposed some new experimental designs, such as D-efficient, Bayesian D-efficient. But insufficient empirical research has been conducted on the effectiveness of these new designs and there has been little comparative analysis of the new designs against the traditional designs. In this paper, a new metro connecting Chengdu and its satellite cities is taken as the research subject to demonstrate the validity of the D-efficient and Bayesian D-efficient design. Comparisons between these new designs and orthogonal design were made by the fit of model and standard deviation of parameters estimation; then the best model result is obtained to analyze the travel choice behavior. The results indicate that Bayesian D-efficient design works better than D-efficient design. Some of the variables can affect significantly the choice behavior of people, including the waiting time and arrival time. The D-efficient and Bayesian D-efficient design for MNL can acquire reliability result in ML model, but the ML model cannot develop the theory advantages of these two designs. Finally, the metro can handle over 40% passengers flow if the metro will be operated in the future.

  20. A Pre-normative study on the cyclic oxidation behaviour of PM chromium: the effect of experimental parameters

    Energy Technology Data Exchange (ETDEWEB)

    Jacob, Y.P.; Haanappel, V.A.C.; Stroosnijder, M.F. [Commission of the European Communities, Ispra (Italy). Joint Research Centre; Caudron, E.; Buscail, H. [Lab. Vellave sur l' Elaboration et l' Etude des Materiaux, Equipe locale Univ. Blaise-Pascal Clermont-Fd 2 (France)

    2001-07-01

    In this study the importance of experimental parameters for the cyclic oxidation behaviour of chromium is discussed. In particular, the effect of different batches, sample geometry, maximum temperature during cyclic oxidation tests, and the effect of isothermal hold-time in relation to the oxidation behaviour are investigated in more detail. It is shown that small differences in the experimental method or material properties could already significantly influence the oxidation kinetics of the material under investigation. Consequently, poorly chosen and/or characterised experimental conditions can cause misleading results and even wrong conclusions. (orig.)

  1. An optimal generic model for multi-parameters and big data optimizing: a laboratory experimental study

    Science.gov (United States)

    Utama, D. N.; Ani, N.; Iqbal, M. M.

    2018-03-01

    Optimization is a process for finding parameter (parameters) that is (are) able to deliver an optimal value for an objective function. Seeking an optimal generic model for optimizing is a computer science study that has been being practically conducted by numerous researchers. Generic model is a model that can be technically operated to solve any varieties of optimization problem. By using an object-oriented method, the generic model for optimizing was constructed. Moreover, two types of optimization method, simulated-annealing and hill-climbing, were functioned in constructing the model and compared to find the most optimal one then. The result said that both methods gave the same result for a value of objective function and the hill-climbing based model consumed the shortest running time.

  2. Experimental study on operating parameters of miniature loop heat pipe with flat evaporator

    International Nuclear Information System (INIS)

    Wang Shuangfeng; Huo Jiepeng; Zhang Xianfeng; Lin Zirong

    2012-01-01

    Miniature loop heat pipe (MLHP) with flat evaporator has been proved that it has the capability to fulfill the demand for the thermal management of high-power electronic system. To employ MLHP into practical application and obtain the best operating parameters, a copper-water MLHP with flat evaporator of 8 mm thick was fabricated and tested in the condition of different condenser locations and operating orientations. The results show that the condenser located close to the evaporator outlet and adverse orientation have positive impact on the operating temperature of the loop, but negative impact on the cooling capability of condenser. For better understanding of their effect on the heat transfer characteristics of MLHP, the start-up behaviors, thermal performance and the operating regimes are explored in detail. - Highlights: ► A copper-water MLHP with flat evaporator of only 8 mm thick was fabricated. ► The MLHP can be applied to electronic cooling. ► The effect of condenser locations was investigated for the first time. ► The experimental results were discussed and analyzed comprehensively. ► Some practical solutions for disadvantages of LHP operation were provided.

  3. Experimental studies on the effects of bolt parameters on the bearing characteristics of reinforced rock.

    Science.gov (United States)

    Cheng, Liang; Zhang, Yidong; Ji, Ming; Zhang, Kai; Zhang, Minglei

    2016-01-01

    Roadways supported by bolts contain support structures that are built into the rock surrounding the roadway, referred to as reinforced rocks in this paper. Using physical model simulation, the paper investigates the bearing characteristics of the reinforced rock under different bolt parameters with incrementally increased load. The experimental results show that the stress at the measurement point inside the structure varies with the kinetic pressure. The stress increases slowly as the load is initially applied, displays accelerated growth in the middle of the loading application, and decreases or remains constant in the later stage of the loading application. The change in displacement of the surrounding rock exhibits the following characteristics: a slow increase when the load is first applied, accelerated growth in the middle stage, and violent growth in the later stage. There is a good correlation between the change in the measured stress and the change in the surrounding rock displacement. Increasing the density of the bolt support and the length and diameter of the bolt improves the load-bearing performance of the reinforced rock, including its strength, internal peak stress, and residual stress. Bolting improves the internal structure of the surrounding rocks, and the deterioration of the surrounding rock decreases with the distance between the bolt supports.

  4. Study of Parameters Effect on Hydrodynamics of a Gas-Solid Chamber Experimentally and Numerically

    Directory of Open Access Journals (Sweden)

    Rahimzadeh Hassan

    2012-04-01

    Full Text Available In this research, gas velocity, initial static bed height and particle size effect on hydrodynamics of a non-reactive gas–solid fluidized bed chamber were studied experimentally and computationally. A multi fluid Eulerian model incorporating the kinetic theory for solid particles was applied to simulate the unsteady state behavior of this chamber and momentum exchange coefficients were calculated by using the Syamlal- O’Brien drag functions. Simulation results were compared with the experimental data in order to validate the CFD model. Pressure drops predicted by the simulations at different particle sizes and initial static bed height were in good agreement with experimental measurements at superficial gas velocity higher than the minimum fluidization velocity. Simulation results also indicated that small bubbles were produced at the bottom of the bed. These bubbles collided with each other as they moved upwards forming larger bubbles. Furthermore, this comparison showed that the model can predict hydrodynamic behavior of gas solid fluidized bed chambers reasonably well.

  5. A study of calculation methodology and experimental measurements of the kinetic parameters for source driven subcritical systems

    International Nuclear Information System (INIS)

    Lee, Seung Min

    2009-01-01

    This work presents a theoretical study of reactor kinetics focusing on the methodology of calculation and the experimental measurements of the so-called kinetic parameters. A comparison between the methodology based on the Dulla's formalism and the classical method is made. The objective is to exhibit the dependence of the parameters on subcriticality level and perturbation. Two different slab type systems were considered: thermal one and fast one, both with homogeneous media. One group diffusion model was used for the fast reactor, and for the thermal system, two groups diffusion model, considering, in both case, only one precursor's family. The solutions were obtained using the expansion method. Also, descriptions of the main experimental methods of measurements of the kinetic parameters are presented in order to put a question about the compatibility of these methods in subcritical region. (author)

  6. Effect of Small Intestine Strangulation Obstruction on Clinical and Histopathological Parameters An Experimental Study in Donkeys

    Directory of Open Access Journals (Sweden)

    Heba Mohamed M. Kuraa

    2011-06-01

    Full Text Available To study clinical and histopathological changes occur within the first 12 hours of strangulating obstruction of the small intestine in equine, twenty five adult donkeys were used in an experimental study. Strangulation obstruction of the small intestine was performed for 3, 6, 9 and 12 hours, respectively. Clinical examination was done before surgery and at 3 hours intervals postoperatively. After euthanasia, histopathological examination was made 10 cm, 1, 2 and 3 meters proximal to the strangulated part. Three hours postoperatively, the animals began to show signs of abdominal pain, they were looking around, stamping the hind feet, falling down suddenly. Nine hours postoperatively, animals showed signs of depression with intermittent nervous movements in the form of circle movement. After 12 hours, the animals were lying down; There were a significant reduction in the body temperature, respiratory rate, pulse rate, heart rate with significant increase in capillary refill time. Macroscopic changes of the strangulated part were congestion, edema, and dark red discoloration of the intestinal wall and mesentery. Distension of the intestine proximal to the strangulation extended more with increase the period of strangulation. Microscopic examination showed showed severe congestion, dark brown to blackish discoloration with fibrous shreds on the strangulated segment. Peticheal hemorrhages were observed in the intestinal wall and its mesentery for a distance up to 3 meters. The severity of signs varies according to the duration of obstruction which could give a remarkable justification of the prognosis of the patient and the availability of treatment.

  7. Experimentally verified inductance extraction and parameter study for superconductive integrated circuit wires crossing ground plane holes

    International Nuclear Information System (INIS)

    Fourie, Coenrad J; Wetzstein, Olaf; Kunert, Juergen; Meyer, Hans-Georg; Toepfer, Hannes

    2013-01-01

    As the complexity of rapid single flux quantum (RSFQ) circuits increases, both current and power consumption of the circuits become important design criteria. Various new concepts such as inductive biasing for energy efficient RSFQ circuits and inductively coupled RSFQ cells for current recycling have been proposed to overcome increasingly severe design problems. Both of these techniques use ground plane holes to increase the inductance or coupling factor of superconducting integrated circuit wires. New design tools are consequently required to handle the new topographies. One important issue in such circuit design is the accurate calculation of networks of inductances even in the presence of finite holes in the ground plane. We show how a fast network extraction method using InductEx, which is a pre- and post-processor for the magnetoquasistatic field solver FastHenry, is used to calculate the inductances of a set of SQUIDs (superconducting quantum interference devices) with ground plane holes of different sizes. The results are compared to measurements of physical structures fabricated with the IPHT Jena 1 kA cm −2 RSFQ niobium process to verify accuracy. We then do a parameter study and derive empirical equations for fast and useful estimation of the inductance of wires surrounded by ground plane holes. We also investigate practical circuits and show excellent accuracy. (paper)

  8. Experimental study on plasma parameters in the mushroom limiter shadow in the T-10 tokamak

    International Nuclear Information System (INIS)

    Alferov, A.A.; Vershkov, V.A.; Grashin, S.A.; Chankin, A.V.

    1988-01-01

    Plasma parameters in the shadow of mashroom limiter installed in the lower tokamak outlet are studied. Investigation into asymmetry of plasma fluxes to the ion and electrone limiter sides leads to a consumption concerning two meachanisms of its occurrance-toroidal plasma rotation and prevailing plasma departure to the wall through the external torus encirclement. Asymmetry of plasma drift potentials near the limiter observed during the experiment leads to current drift through the limiter close to Spitzer j s one. It is shown that with the increase of mean plasma density the plasma density in the limiter channels grows and its temperature is decreased so the charged particle losses for the limiter are weakly dependent on the mean density which is connected with plasma confinement degradation under the density reduction. A complete flux of charged particles to the limiter is comparable to their flux from plasma filament. Plasma flux into the channels is close to ambipolar one and the power fluxes to neutralization plates are of the order of 10 j s Te/e. Neutral gas pressure dependence in the volume under the limiter on the plasma fluxes to channels is nonlinear, the maximum pressure achieves 3x10 -2 T

  9. Experimental study and process parameters analysis on the vacuum cooling of iceberg lettuce

    International Nuclear Information System (INIS)

    He Suyan; Li Yunfei

    2008-01-01

    The vacuum cooling of iceberg lettuce was described in this paper. Based on the energy and mass balance, a mathematical model was developed to analyze the performance of the vacuum cooler and the evaporation-boiling phenomena during vacuum cooling of iceberg lettuce. The temporal trends of total system pressure, produce temperature such as surface temperature, center temperature, mass-average temperature, the weight loss of iceberg lettuce during vacuum cooling were predicted. Validation experimentation is achieved in the designed vacuum cooler. The experimental data were compared with the simulation results. It was found that the differences of the temperature between the simulation and the experiments were within 1 deg. C. The amount of water evaporated from the iceberg lettuce by simulation was 3.32% during the whole vacuum cooling, while the tested water loss rate was 2.97%, the maximal deviation of weight loss was within 0.59%. The simulation results agreed well with the experimental data

  10. Experimental study and process parameters analysis on the vacuum cooling of iceberg lettuce

    Energy Technology Data Exchange (ETDEWEB)

    He Suyan [School of Mechanical and Electrical Engineering, Qingdao University, Qingdao 266071 (China)], E-mail: hesuyan67829@sina.com; Li Yunfei [Department of Food Science and Engineering, School of Agriculture and Biology, Shanghai Jiao Tong University (China)

    2008-10-15

    The vacuum cooling of iceberg lettuce was described in this paper. Based on the energy and mass balance, a mathematical model was developed to analyze the performance of the vacuum cooler and the evaporation-boiling phenomena during vacuum cooling of iceberg lettuce. The temporal trends of total system pressure, produce temperature such as surface temperature, center temperature, mass-average temperature, the weight loss of iceberg lettuce during vacuum cooling were predicted. Validation experimentation is achieved in the designed vacuum cooler. The experimental data were compared with the simulation results. It was found that the differences of the temperature between the simulation and the experiments were within 1 deg. C. The amount of water evaporated from the iceberg lettuce by simulation was 3.32% during the whole vacuum cooling, while the tested water loss rate was 2.97%, the maximal deviation of weight loss was within 0.59%. The simulation results agreed well with the experimental data.

  11. Residual waters treatment by heterogeneous photocatalysis: a study of experimental parameters applied to the photoelectrocatalysis

    Directory of Open Access Journals (Sweden)

    Henrique de Santana

    2006-02-01

    Full Text Available In this paper, the use of electrochemically-assisted heterogeneous photo-catalysis will be discussed. Several operational parameters will also be discussed, in order to achieve optimum efficiency of this photo-degradation system, such as: the influence of variables as support electrolyte, applied potential, dye initial concentration, pH and choice of a UV source on dye degradation.

  12. Experimental study of some homeostatic parameters at late times after exposure to radiation

    International Nuclear Information System (INIS)

    Chertkov, K.S.; Andrianova, I.E.; Atamanova, O.M.; Filimonova, G.I.; Nesterova, T.A.; Sbitneva, M.F.; Glushkov, V.A.; Chotij, V.G.; Stejmatskaya, Z.A.

    1994-01-01

    Following radiation damage from LD 50 - LD 97 , changes in blood, immune and endocrine parameters were revealed and followed up in dogs at the time of late effects development, 3-18 months after exposure. The changes result from post-radiation immunodeficiency and resemble those observed in residents of radioactive contaminate areas or in men participated in Chernobyl accident amelioration

  13. Experimental parameter study for passive vortex generators on a 30% thick airfoil

    NARCIS (Netherlands)

    Baldacchino, D.; Simao Ferreira, C.; De Tavernier, D.A.M.; Timmer, W.A.; van Bussel, G.J.W.

    2018-01-01

    Passive vane-type vortex generators (VGs) are commonly used on wind turbine blades to mitigate the effects of flow separation. However, significant uncertainty surrounds VG design guidelines. Understanding the influence of VG parameters on airfoil performance requires a systematic approach

  14. Experimental study on two-phase flow parameters of subcooled boiling in inclined annulus

    International Nuclear Information System (INIS)

    Lee, Tae Ho; Kim, Moon Oh; Park, Goon Cherl

    1999-01-01

    Local two-phase flow parameters of subcooled flow boiling in inclined annulus were measured to investigate the effect of inclination on the internal flow structure. Two-conductivity probe technique was applied to measured local gas phasic parameters, including void by fraction, vapor bubble frequency, chord length, vapor bubble velocity and interfacial area concentration. Local liquid velocity was measured by Pitot tube. Experiments were conducted for three angles of inclination: 0 o (vertical), 30 o , 60 o . The system pressure was maintained at atmospheric pressure. The range of average void fraction was up to 10 percent and the average liquid superficial velocities were less than 1.3 m/sec. The results of experiments showed that the distributions of two-phase flow parameters were influenced by the angle of channel inclination. Especially, the void fraction and chord length distributions were strongly affected by the increase of inclination angle, and flow pattern transition to slug flow was observed depending on the flow conditions. The profiles of vapor velocity, liquid velocity and interfacial area concentration were found to be affected by the non-symmetric bubble size distribution in inclined channel. Using the measured distributions of local phasic parameters, an analysis for predicting average void fraction was performed based on the drift flux model and flowing volumetric concentration. And it was demonstrated that the average void fraction can be more appropriately presented in terms of flowing volumetric concentration. (Author). 18 refs., 2 tabs., 18 figs

  15. Study of experimentally undetermined neutrino parameters in the light of baryogenesis considering type I and type II Seesaw models

    International Nuclear Information System (INIS)

    Kalita, Rupam

    2017-01-01

    We study to connect all the experimentally undetermined neutrino parameters namely lightest neutrino mass, neutrino CP phases and baryon asymmetry of the Universe within the framework of a model where both type I and type II seesaw mechanisms can contribute to tiny neutrino masses. In this work we study the effects of Dirac and Majorana neutrino phases in the origin of matter-antimatter asymmetry through the mechanism of leptogenesis. Type I seesaw mass matrix considered to a tri-bimaximal (TBM) type neutrino mixing which always gives non zero reactor mixing angle. The type II seesaw mass matrix is then considered in such a way that the necessary deviation from TBM mixing and the best fit values of neutrino parameters can be obtained when both type I and type II seesaw contributions are taken into account. We consider different contribution from type I and type II seesaw mechanism to study the effects of neutrino CP phases in the baryon asymmetry of the universe. We further study to connect all these experimentally undetermined neutrino parameters by considering various contribution of type I and type II seesaw. (author)

  16. Parameter design and experimental study of a bifunctional isolator for optical payload protection and stabilization

    Science.gov (United States)

    Wang, Guang-yuan; Guan, Xin; Cao, Dong-jing; Tang, Shao-fan; Chen, Xiang; Liang, Lu; Zheng, Gang-tie

    2017-11-01

    With the raise of resolution, optical payloads are becoming increasingly sensitive to satellite jitter. An approach where the entire spacecraft is pointed with great accuracy requires sophisticated and expensive bus design. In an effort to lower the overall cost of space missions that require highly stable line-of-sight pointing, a method of separating the bus and the payload with low frequency isolators is proposed. This isolation system can block the transmission of disturbance and allow relatively large bus motion. However, if the isolator is linear then there is a trade-off between isolation and static deflection as the launch and the on-orbit stage have difference requirements on the isolation frequency. Otherwise, an extra locking system should be appended to protect the payload before getting into orbit, as the STABLE isolation system[1] and the MIM isolation system[2] did. To overcome this limitation, an alternative approach is to design a nonlinear isolator with high-static stiffness during launch and low dynamic stiffness on orbit. Several specially designed nonlinear isolators have achieved low dynamic stiffness with large static load capacity. Virgin[3] considered a structure made from a highly deformed elastic element to achieve a softening spring. Platus[4] exploited the buckling of beams under axial load in a specific configuration to achieve a negative stiffness in combination with a positive stiffness, and hence low-dynamic stiffness. Others have achieved the same by connecting linear springs with positive stiffness in parallel with elements of negative stiffness[5] [7]. In the present study, a bifunctional isolator has been developed for optical payloads. The isolator have good performance both during launch and on orbit because of its specially designed nonlinear stiffness and damping. The isolator works in a linear part with low stiffness and small damping ratio under the micro-vibration and microgravity on orbit. The transmissibility

  17. Experimental study and process parameters analysis on the vacuum cooling of iceberg lettuce

    Energy Technology Data Exchange (ETDEWEB)

    He, Su-Yan [School of Mechanical and Electrical Engineering, Qingdao University, Qingdao 266071 (China); Li, Yun-Fei [Department of Food Science and Engineering, School of Agriculture and Biology, Shanghai Jiao Tong University (China)

    2008-10-15

    The vacuum cooling of iceberg lettuce was described in this paper. Based on the energy and mass balance, a mathematical model was developed to analyze the performance of the vacuum cooler and the evaporation-boiling phenomena during vacuum cooling of iceberg lettuce. The temporal trends of total system pressure, produce temperature such as surface temperature, center temperature, mass-average temperature, the weight loss of iceberg lettuce during vacuum cooling were predicted. Validation experimentation is achieved in the designed vacuum cooler. The experimental data were compared with the simulation results. It was found that the differences of the temperature between the simulation and the experiments were within 1{sup o}C. The amount of water evaporated from the iceberg lettuce by simulation was 3.32% during the whole vacuum cooling, while the tested water loss rate was 2.97%, the maximal deviation of weight loss was within 0.59%. The simulation results agreed well with the experimental data. (author)

  18. Tire-road noise: an experimental study of tire and road design parameters

    OpenAIRE

    Bekke, Dirk; Wijnant, Ysbrand H.; Weegerink, Thijs; de Boer, Andries

    2013-01-01

    It is widely known that road traffic noise has negative influences on human health. Hence, as tire-road noise is considered to be the most dominant cause of road traffic noise above 30-50 km/h, a lot of research is performed by the two involving industries: road authorities/manufacturers and tire manufacturers. Usually, the parameters influencing exterior tire-road noise are often examined separately, whereas it is the tire-road interaction which obviously causes the actual noise. An integral...

  19. Experimental study on effects of drilling parameters on respirable dust production during roof bolting operations.

    Science.gov (United States)

    Jiang, Hua; Luo, Yi; McQuerrey, Joe

    2018-02-01

    Underground coalmine roof bolting operators exhibit a continued risk for overexposure to airborne levels of respirable coal and crystalline silica dust from the roof drilling operation. Inhaling these dusts can cause coal worker's pneumoconiosis and silicosis. This research explores the effect of drilling control parameters, specifically drilling bite depth, on the reduction of respirable dust generated during the drilling process. Laboratory drilling experiments were conducted and results demonstrated the feasibility of this dust control approach. Both the weight and size distribution of the dust particles collected from drilling tests with different bite depths were analyzed. The results showed that the amount of total inhalable and respirable dust was inversely proportional to the drilling bite depth. Therefore, control of the drilling process to achieve proper high-bite depth for the rock can be an important approach to reducing the generation of harmful dust. Different from conventional passive engineering controls, such as mist drilling and ventilation approaches, this approach is proactive and can cut down the generation of respirable dust from the source. These findings can be used to develop an integrated drilling control algorithm to achieve the best drilling efficiency as well as reducing respirable dust and noise.

  20. A comparative study of parameters used in design and operation of desalination experimental facility versus the process parameters in a commercial desalination plant

    International Nuclear Information System (INIS)

    Hanra, M.S.; Verma, R.K.; Ramani, M.P.S.

    1982-01-01

    Desalination Experimental Facility (DEF) based on multistage flash desalination process has been set up by the Desalination Division of the Bhabha Atomic Research Centre, Bombay. The design parameters of DEF and materials used for various equipment and parts of DEF are mentioned. DEF was operated for 2300 hours in six operational runs. The range of operational parameters maintained during operation and observations on the performance of the materials of construction are given. Detailed comparison has been made for the orocess parameters in DEF and those in a large size plant. (M.G.B.)

  1. Experimental study on the strength parameter of Quarry Dust mixed Coconut Shell Concrete adding Coconut Fibre

    Science.gov (United States)

    Matangulu Shrestha, Victor; Anandh, S.; Sindhu Nachiar, S.

    2017-07-01

    Concrete is a heterogeneous mixture constitute of cement as the main ingredient with a different mix of fine and coarse aggregate. The massive use of conventional concrete has a shortfall in its key ingredients, natural sand and coarse aggregate, due to increased industrialisation and globalisation. To overcome the shortage of material, an alternate material with similar mechanical properties and composition has to be studied, as replacement of conventional concrete. Coconut shell concrete is a prime option as replacement of key ingredients of conventional concrete as coconut is produced in massive quantity in south East Asia. Coconut shell concrete is lightweight concrete and different research is still ongoing concerning about its mix design and composition in the construction industry. Concrete is weak in tension as compared to compression, hence the fibre is used to refrain the crack in the concrete. Coconut fibre is one of many fibres which can be used in concrete. The main aim of this project is to analyse the use of natural by-products in the construction industry, make light weight concrete and eco-friendly construction. This project concerns with the comparison of the mechanical properties of coconut shell concrete and conventional concrete, replacing fine aggregate with quarry dust using coconut fibre. M25 grade of concrete was adopted and testing of concrete was done at the age of 3, 7 and 28 days. In this concrete mix, sand was replaced completely in volumetric measurement by quarry dust. The result was analysed and compared with addition of coconut fibre at varying percentage of 1%, 2%, 3%, 4% and 5%. From the test conducted, coconut shell concrete with quarry dust has the maximum value at 4% of coconut fibre while conventional concrete showed the maximum value at 2% of coconut fibre.

  2. Experimental Study of Direct Laser Deposition of Ti-6Al-4V and Inconel 718 by Using Pulsed Parameters

    Directory of Open Access Journals (Sweden)

    Kamran Shah

    2014-01-01

    Full Text Available Laser direct metal deposition (LDMD has developed from a prototyping to a single metal manufacturing tool. Its potential for creating multimaterial and functionally graded structures is now beginning to be explored. This work is a first part of a study in which a single layer of Inconel 718 is deposited on Ti-6Al-4V substrate. Single layer tracks were built at a range of powder mass flow rates using a coaxial nozzle and 1.5 kW diode laser operating in both continuous and pulsed beam modes. This part of the study focused on the experimental findings during the deposition of Inconel 718 powder on Ti-6Al-4V substrate. Scanning electron microscopy (SEM and X-ray diffraction analysis were performed for characterization and phase identification. Residual stress measurement had been carried out to ascertain the effects of laser pulse parameters on the crack development during the deposition process.

  3. Experimental determination of mechanical parameters in sensorless ...

    Indian Academy of Sciences (India)

    V S S PAVAN KUMAR HARI

    pulse width modulation (PWM) selected. The three-phase .... and the simulation and experimental results are presented. ... between 0 and Ts due to the process of PWM. Hence, the .... MATLAB SIMULINK with the machine parameters in.

  4. An experimental hut study to quantify the effect of DDT and airborne pyrethroids on entomological parameters of malaria transmission

    Science.gov (United States)

    2014-01-01

    Background Current malaria vector control programmes rely on insecticides with rapid contact toxicity. However, spatial repellents can also be applied to reduce man-vector contact, which might ultimately impact malaria transmission. The aim of this study was to quantify effects of airborne pyrethroids from coils and DDT used an indoor residual spray (IRS) on entomological parameters that influence malaria transmission. Methods The effect of Transfluthrin and Metofluthrin coils compared to DDT on house entry, exit and indoor feeding behaviour of Anopheles gambiae sensu lato were measured in experimental huts in the field and in the semi-field. Outcomes were deterrence - reduction in house entry of mosquitoes; irritancy or excito-repellency – induced premature exit of mosquitoes; blood feeding inhibition and effect on mosquito fecundity. Results Transfluthrin coils, Metofluthrin coils and DDT reduced human vector contact through deterrence by 38%, 30% and 8%, respectively and induced half of the mosquitoes to leave huts before feeding (56%, 55% and 48%, respectively). Almost all mosquitoes inside huts with Metofluthrin and Transfluthrin coils and more than three quarters of mosquitoes in the DDT hut did not feed, almost none laid eggs and 67%, 72% and 70% of all mosquitoes collected from Transfluthrin, Metofluthrin and DDT huts, respectively had died after 24 hours. Conclusion This study highlights that airborne pyrethroids and DDT affect a range of anopheline mosquito behaviours that are important parameters in malaria transmission, namely deterrence, irritancy/excito-repellency and blood-feeding inhibition. These effects are in addition to significant toxicity and reduced mosquito fecundity that affect mosquito densities and, therefore, provide community protection against diseases for both users and non-users. Airborne insecticides and freshly applied DDT had similar effects on deterrence, irritancy and feeding inhibition. Therefore, it is suggested that

  5. An experimental hut study to quantify the effect of DDT and airborne pyrethroids on entomological parameters of malaria transmission.

    Science.gov (United States)

    Ogoma, Sheila B; Lorenz, Lena M; Ngonyani, Hassan; Sangusangu, Robert; Kitumbukile, Mohammed; Kilalangongono, Masoudi; Simfukwe, Emmanuel T; Mseka, Anton; Mbeyela, Edgar; Roman, Deogratius; Moore, Jason; Kreppel, Katharina; Maia, Marta F; Moore, Sarah J

    2014-04-01

    Current malaria vector control programmes rely on insecticides with rapid contact toxicity. However, spatial repellents can also be applied to reduce man-vector contact, which might ultimately impact malaria transmission. The aim of this study was to quantify effects of airborne pyrethroids from coils and DDT used an indoor residual spray (IRS) on entomological parameters that influence malaria transmission. The effect of Transfluthrin and Metofluthrin coils compared to DDT on house entry, exit and indoor feeding behaviour of Anopheles gambiae sensu lato were measured in experimental huts in the field and in the semi-field. Outcomes were deterrence--reduction in house entry of mosquitoes; irritancy or excito-repellency--induced premature exit of mosquitoes; blood feeding inhibition and effect on mosquito fecundity. Transfluthrin coils, Metofluthrin coils and DDT reduced human vector contact through deterrence by 38%, 30% and 8%, respectively and induced half of the mosquitoes to leave huts before feeding (56%, 55% and 48%, respectively). Almost all mosquitoes inside huts with Metofluthrin and Transfluthrin coils and more than three quarters of mosquitoes in the DDT hut did not feed, almost none laid eggs and 67%, 72% and 70% of all mosquitoes collected from Transfluthrin, Metofluthrin and DDT huts, respectively had died after 24 hours. This study highlights that airborne pyrethroids and DDT affect a range of anopheline mosquito behaviours that are important parameters in malaria transmission, namely deterrence, irritancy/excito-repellency and blood-feeding inhibition. These effects are in addition to significant toxicity and reduced mosquito fecundity that affect mosquito densities and, therefore, provide community protection against diseases for both users and non-users. Airborne insecticides and freshly applied DDT had similar effects on deterrence, irritancy and feeding inhibition. Therefore, it is suggested that airborne pyrethroids, if delivered in suitable

  6. Gadolinium as a CT contrast agent: an experimental study for the effects of injection parameters in the rabbit brain model

    International Nuclear Information System (INIS)

    Kim, Hyun Jin; Choi, Hye Young; Lee, Sun Wha; Hwang, Ji Young

    2005-01-01

    We wanted to investigate the use of gadolinium based contrast agent (Gd-DTPA) for computed tomography (CT), and we also wanted to assess the effects of valuable injection parameters on enhancement in an experimental rabbit brain model. In vitro, attenuation measurements of serial dilutions of Gd-DTPA and iopromide were compared. In five rabbits, single level dynamic gadolinium-enhanced brain CT studies were obtained using different injection parameters. A comparision CT scan after iopromide administration was performed. The time-attenuation curves of the brain vessel and parenchyma were obtained and the magnitude of enhancement (Hmax) and the time to peak enhancement (Tmax) were analyzed. In vitro, the attenuation coefficient of undiluted Gd-DTPA (2,578 HU) was higher than that of iopromide (1,761 HU) at equimolar concentrations. In 5 rabbits, the time-attenuation curve demonstrated a distinct pattern with peak enhancement only in the brain vessel, but not in the brain parenchyma. There was increasing linear relationship between the injection rate of Gd-DTPA and Hmax, and a declining linear relationship with Tmax. The higher the concentration of Gd-DTPA, the higher Hmax was, but no significant difference was found for the Tmax. Higher volumes of Gd-DTPA revealed a higher Hmax and a delayed Tmax. Enhancement of the brain parenchyma on gadolinium-enhanced CT is minimal, while enhancement of the brain vessels is distinctive. The most important factor affecting Hmax of the vessel is the concentration of the contrast medium and the most important factor affecting Tmax of the vessel is volume of the contrast medium. The gadolinium-based contrast agent may be an reasonable alternative contrast agent for brain CT, and especially in cerebral vessels, and it may also be advantageous for brain parenchyma of those patients with BBB dysfunction

  7. Prediction of the time course of callus stiffness as a function of mechanical parameters in experimental rat fracture healing studies--a numerical study.

    Directory of Open Access Journals (Sweden)

    Tim Wehner

    Full Text Available Numerous experimental fracture healing studies are performed on rats, in which different experimental, mechanical parameters are applied, thereby prohibiting direct comparison between each other. Numerical fracture healing simulation models are able to predict courses of fracture healing and offer support for pre-planning animal experiments and for post-hoc comparison between outcomes of different in vivo studies. The aims of this study are to adapt a pre-existing fracture healing simulation algorithm for sheep and humans to the rat, to corroborate it using the data of numerous different rat experiments, and to provide healing predictions for future rat experiments. First, material properties of different tissue types involved were adjusted by comparing experimentally measured callus stiffness to respective simulated values obtained in three finite element (FE models. This yielded values for Young's moduli of cortical bone, woven bone, cartilage, and connective tissue of 15,750 MPa, 1,000 MPa, 5 MPa, and 1 MPa, respectively. Next, thresholds in the underlying mechanoregulatory tissue differentiation rules were calibrated by modifying model parameters so that predicted fracture callus stiffness matched experimental data from a study that used rigid and flexible fixators. This resulted in strain thresholds at higher magnitudes than in models for sheep and humans. The resulting numerical model was then used to simulate numerous fracture healing scenarios from literature, showing a considerable mismatch in only 6 of 21 cases. Based on this corroborated model, a fit curve function was derived which predicts the increase of callus stiffness dependent on bodyweight, fixation stiffness, and fracture gap size. By mathematically predicting the time course of the healing process prior to the animal studies, the data presented in this work provides support for planning new fracture healing experiments in rats. Furthermore, it allows one to transfer and

  8. An experimental study of dependence of hydro turbine vibration parameters on pressure pulsations in the flow path

    Science.gov (United States)

    Dekterev, D.; Maslennikova, A.; Abramov, A.

    2017-09-01

    The operation modes of the hydraulic power plant water turbine with the formation of a precessing vortex core were studied on the hydrodynamic set-up with the model of hydraulic unit. The dependence of low-frequency vibrations on flow pressure pulsations in the hydraulic unit was established. The results of the air injection effect on the vibrational parameters of the hydrodynamic set-up were presented.

  9. Experimental studies

    International Nuclear Information System (INIS)

    Cowser, K.E.; Stansbury, P.S.; Poston, J.W.; Deus, S.F.; Chen, W.L.; Roswell, R.L.; Goans, R.E.; Cantrell, J.H. Jr.

    1978-01-01

    Spectral fluence measurements in an adult phantom are reported. A NaI(Tl) probe was used in various locations within the phantom and pulse-height spectra were obtained for seven beam configurations and three generating potentials. Some typical spectra results are presented. A comparison of calculated dose to experimental measurements is presented

  10. A Comparative Experimental Study on the Use of Machine Learning Approaches for Automated Valve Monitoring Based on Acoustic Emission Parameters

    Science.gov (United States)

    Ali, Salah M.; Hui, K. H.; Hee, L. M.; Salman Leong, M.; Al-Obaidi, M. A.; Ali, Y. H.; Abdelrhman, Ahmed M.

    2018-03-01

    Acoustic emission (AE) analysis has become a vital tool for initiating the maintenance tasks in many industries. However, the analysis process and interpretation has been found to be highly dependent on the experts. Therefore, an automated monitoring method would be required to reduce the cost and time consumed in the interpretation of AE signal. This paper investigates the application of two of the most common machine learning approaches namely artificial neural network (ANN) and support vector machine (SVM) to automate the diagnosis of valve faults in reciprocating compressor based on AE signal parameters. Since the accuracy is an essential factor in any automated diagnostic system, this paper also provides a comparative study based on predictive performance of ANN and SVM. AE parameters data was acquired from single stage reciprocating air compressor with different operational and valve conditions. ANN and SVM diagnosis models were subsequently devised by combining AE parameters of different conditions. Results demonstrate that ANN and SVM models have the same results in term of prediction accuracy. However, SVM model is recommended to automate diagnose the valve condition in due to the ability of handling a high number of input features with low sampling data sets.

  11. Experimental study on Response Parameters of Ni-rich NiTi Shape Memory Alloy during Wire Electric Discharge Machining

    Science.gov (United States)

    Bisaria, Himanshu; Shandilya, Pragya

    2018-03-01

    Nowadays NiTi SMAs are gaining more prominence due to their unique properties such as superelasticity, shape memory effect, high fatigue strength and many other enriched physical and mechanical properties. The current studies explore the effect of machining parameters namely, peak current (Ip), pulse off time (TOFF), and pulse on time (TON) on wire wear ratio (WWR), and dimensional deviation (DD) in WEDM. It was found that high discharge energy was mainly ascribed to high WWR and DD. The WWR and DD increased with the increase in pulse on time and peak current whereas high pulse off time was favourable for low WWR and DD.

  12. DFT and experimental studies on structure and spectroscopic parameters of 3,6-diiodo-9-ethyl-9H-carbazole

    DEFF Research Database (Denmark)

    Radula-Janik, Klaudia; Kupka, Teobald; Ejsmont, Krzysztof

    2016-01-01

    The first report on crystal and molecular structure of 3,6-diiodo-9-ethyl-9H-carbazole is presented. Experimental room-temperature X-ray and 13C chemical shift studies were supported by advanced theoretical calculations using density functional theory (DFT). The 13C nuclear magnetic shieldings were...... predicted at the non-relativistic and relativistic level of theory using the zeroth-order regular approximation (ZORA). Theoretical relativistic calculations of chemical shifts of carbons C3 and C6, directly bonded to iodine atoms, produced a reasonable agreement with experiment (initial deviation from...

  13. Experimental study on effect of hydroalcoholic extract of Emblica officinalis fruits on glucose homeostasis and metabolic parameters

    Science.gov (United States)

    Patel, Snehal S.; Goyal, Ramesh K.; Shah, Rajendra S.; Tirgar, Pravin R.; Jadav, Pinakin D.

    2013-01-01

    Polyphenols from natural source are potential therapeutics that act alone or supplement anti-diabetic drugs in the prevention and treatment of diabetes. The present investigation was undertaken to study the effect of hydroalcoholic extract (HE) of fruits of Emblica officinalis on type 1 diabetic rats. Diabetes was induced by streptozotocin (STZ) (45 mg/kg i.v.). HE (100 mg/kg, p.o.) was administered for 4 weeks and at the end of treatment, blood samples were collected and analyzed for various biochemical parameters. STZ produced a diabetic state exhibiting all the cardinal symptoms such as loss of body weight, polydipsia, polyuria, glucosuria, polyphagia, hypoinsulinemia, and hyperglycemia associated with hypercholesterolemia and hypertriglyceridemia. Treatment with HE prevented cardinal symptoms and caused significant decrease in fasting serum glucose, AUCglucose, cholesterol, triglyceride, low-density lipoprotein (LDL) and very LDL in diabetic rats. However, insulin, AUCinsulin, and serum high-density lipoprotein level were not significantly altered by treatment. Treatment also reduced lipid peroxidation and increased anti-oxidant parameters in the liver homogenates of diabetic rats. Polyphenol enriched fraction of HE significantly improved disarranged carbohydrate and lipid metabolism of chemically induced diabetes in rats. The mechanism of its anti-diabetic activity appears to be either improvement in peripheral glucose utilization, increased insulin sensitivity, or anti-oxidant property. PMID:24696584

  14. Towards optimization of experimental parameters for studying Li-O2 battery discharge products in TEM using in situ EELS.

    Science.gov (United States)

    Basak, Shibabrata; Jansen, Jacob; Kabiri, Yoones; Zandbergen, Henny W

    2018-05-01

    The key to understanding the performance of Li-O 2 batteries is to study the chemical and structural properties of their discharge product(s) at the nanometer scale. Using TEM for this purpose poses challenges due to the sensitivity of samples to air and electron beams. This paper describes our use of in situ EELS to evaluate experimental procedures to reduce electron-beam degradation and presents methods to deal with air sensitivity. Our results show that Li 2 O 2 decomposition is dependent on the total dose and is approximately 4-5 times more pronounced at 80 than at 200 kV. We also demonstrate the benefits of using low-dose-rate STEM. We show further that a "graphene cell", which encapsulates the sample within graphene sheets, can protect the sample against air and e-beam damage. Copyright © 2018 Elsevier B.V. All rights reserved.

  15. Design, calculation and experimental studies for liquid metal system main parameters in support of the liquid lithium fusion reactor

    International Nuclear Information System (INIS)

    Evtikhin, V.A.; Lyublinski, I.E.; Vertkov, A.V.

    2001-01-01

    A new concept of a Liquid Lithium Fusion Reactor and the first experimental results were presented at the 16th IAEA Conference on Fusion Energy. During the past two years theoretical estimations have been made, and calculated and experimental results have been obtained in confirmation of this concept and supporting its progress. The main results of this work are given in the paper. (author)

  16. Design, calculation and experimental studies for liquid metal system main parameters in support of the liquid lithium fusion reactor

    International Nuclear Information System (INIS)

    Evtikhin, V.A.; Lyublinski, I.E.; Vertkov, A.V.

    1999-01-01

    A new concept of a Liquid Lithium Fusion Reactor and the first experimental results were presented at the 16th IAEA Conference on Fusion Energy. During the past two years theoretical estimations have been made, and calculated and experimental results have been obtained in confirmation of this concept and supporting its progress. The main results of this work are given in the paper. (author)

  17. The quality of reconstructed 3D images in multidetector-row helical CT: experimental study involving scan parameters

    International Nuclear Information System (INIS)

    Shin, Ji Hoon; Lee, Ho Kyu; Choi, Choong Gon; Suh, Dae Chul; Lim, Tae Hwan; Kang, Weechang

    2002-01-01

    To determine which multidetector-row helical CT scanning technique provides the best-quality reconstructed 3D images, and to assess differences in image quality according to the levels of the scanning parameters used. Four objects with different surfaces and contours were scanned using multidetector-row helical CT at three detector-row collimations (1.25, 2.50, 5.00 mm), two pitches (3.0, 6.0), and three different degrees of overlap between the reconstructed slices (0%, 25%, 50%). Reconstructed 3D images of the resulting 72 sets of data were produced using volumetric rendering. The 72 images were graded on a scale from 1 (worst) to 5 (best) for each of four rating criteria, giving a mean score for each criterion and an overall mean score. Statistical analysis was used to assess differences in image quality according to scanning parameter levels. The mean score for each rating criterion, and the overall mean score, varied significantly according to the scanning parameter levels used. With regard to detector-row collimation and pitch, all levels of scanning parameters gave rise to significant differences, while in the degree of overlap of reconstructed slices, there were significant differences between overlap of 0% and of 50% in all levels of scanning parameters, and between overlap of 25% and of 50% in overall accuracy and overall mean score. Among the 18 scanning sequences, the highest score (4.94) was achieved with 1.25 mm detector-row collimation, 3.0 pitch, and 50% overlap between reconstructed slices. Comparison of the quality of reconstructed 3D images obtained using multidetector-row helical CT and various scanning techniques indicated that the 1.25 mm, 3.0, 50% scanning sequence was best. Quality improved as detector-row collimation decreased; as pitch was reduced from 6.0 to 3.0; and as overlap between reconstructed slices increased

  18. Simultaneous estimation of experimental and material parameters

    CSIR Research Space (South Africa)

    Jansen van Rensburg, GJ

    2012-07-01

    Full Text Available to the experimental data. An inverse analysis is performed that determines material properties and boundary conditions simultaneously. This idea is investigated using virtual experimental data. The virtual experimental data is obtained by performing a finite element...

  19. Experimental Study of Three-body Cabibbo-suppressed D0 Decays and Extraction of Cp Violation Parameters

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Kalanand; /Nehru U.

    2008-02-22

    The authors present measurements of the relative branching ratios, Dalitz plot structures and CP-asymmetry values in the three-body singly Cabibbo-suppressed decays D{sup 0} {yields} {pi}{sup -}{pi}{sup +}{pi}{sup 0} and D{sup 0} {yields} K{sup -}K{sup +}{pi}{sup 0} using data collected by the BABAR detector at the PEP-II asymmetric-energy ring at SLAC. The author applies the results of the D{sup 0} {yields} {pi}{sup -}{pi}{sup +}{pi}{sup 0} analysis to extracting CP-violation parameters related to the CKM angle {gamma} (or {phi}{sub 3}) using the decay B{sup -} {yields} D{sub {pi}{sup +}{pi}{sup -}{pi}{sup 0}} K{sup -}.

  20. An experimental study of the effects of combined exposure to microwave and heat on gene expression and sperm parameters in mice

    Directory of Open Access Journals (Sweden)

    Faezeh A Gohari

    2017-01-01

    Full Text Available Objectives: Separate exposure to microwaves (MWs or heat had effects on expression levels of Bax and Bcl-2 and sperm parameters in studied group. Aims: The objectives of this research were to determine the effects of separate and combined exposure to 900-MHz MW (as representative of cell phone radiation and heat on gene expression and spermogram of male mice. Settings and Design: This experimental animal study was conducted in the school of public health. Materials and Methods: The study was done on 12 male mice randomly divided into four groups (21–23 g: control, test group 1 with separate exposure to 900-MHz MW, test group 2 with separate exposure to hot and sultry climate, and test group 3 with simultaneous whole body exposures to 900-MHz MW and hot and sultry climate. In all studied groups, gene expression and sperm parameters were measured. Results: Tissue samples in all test groups showed integrity of the seminiferous tubule followed by all types of germ line cells. Significant increases in the number of dead sperms in mice with separate exposure to heat were observed in comparison with the other studied groups (P < 0.05. The ratio of Bax expression was elevated to 0.015 ± 0.006 in mice after combined exposures to 900-MHz MW and heat. Conclusion: Separate and combined exposure to 900-MHz MW and heat may induce adverse effects on sperm parameters and gene expression of studied male mice.

  1. Experimental and ab initio study of the hyperfine parameters of ZnFe {sub 2}O{sub 4} with defects

    Energy Technology Data Exchange (ETDEWEB)

    Quintero, J. Melo; Salcedo Rodríguez, K. L.; Pasquevich, G. A.; Zélis, P. Mendoza; Stewart, S. J., E-mail: stewart@fisica.unlp.edu.ar; Rodríguez Torres, C. E.; Errico, L. A. [Universidad Nacional de La Plata, IFLP-CCT- La Plata-CONICET and Departamento de Física, Facultad de Ciencias Exactas, C. C. 67 (Argentina)

    2016-12-15

    We present a combined Mössbauer and ab initio study on the influence of oxygen-vacancies on the hyperfine and magnetic properties of the ZnFe {sub 2}O{sub 4} spinel ferrite. Samples with different degree of oxygen-vacancies were obtained from zinc ferrite powder that was thermally treated at different temperatures up to 650 {sup ∘}C under vacuum.Theoretical calculations of the hyperfine parameters, magnetic moments and magnetic alignment have been carried out considering different defects such as oxygen vacancies and cation inversion. We show how theoretical and experimental approaches are complementary to characterize the local structure around Fe atoms and interpret the observed changes in the hyperfine parameters as the level of defects increases.

  2. ATLAS parameter study

    International Nuclear Information System (INIS)

    Adler, R.J.

    1994-01-01

    The purpose of this study is to make an independent assessment on the parameters chosen for the ATLAS capacitor bank at LANL. The contractor will perform a study of the basic pulsed power parameters of the ATLAS device with baseline functional parameters of >25 MA implosion current and <2.5 microsecond current risetime. Nominal circuit parameters held fixed will be the 14 nH from the vacuum interface to the load, and the nominal load impedances of 1 milliohm for slow loads and 10 milliohms for fast loads. Single Ended designs, as opposed to bipolar designs, will be studied in detail. The ATLAS pulsed power design problem is about inductance. The reason that a 36 MJ bank is required is that such a bank has enough individual capacitors so that the parallel inductance is acceptably low. Since about half the inductance is in the bank, and the inductance and time constant of the submodules is fixed, the variation of output with a given parameter will generally be a weak one. In general, the dl/dt calculation demonstrates that for the real system inductances, 700 kV is the optimum voltage for the bank to drive X-ray loads. The optimum is broad, and there is little reduction in performance at voltages as low as 450 kV. The direct drive velocity analysis also shows that the optimum velocity is between 480 and 800 kV for a variety of assumptions, and that there is less than a 10% variation in velocity over this range. Voltages in the 120 kV--600 kV range are desirable for driving heavy liners. A compromise optimum operating point might be 480 kV, at which all X-ray operation scenarios are within 10% of their velocity optimum, and heavy liners can be configured to be near optimum if small enough. Based on very preliminary studies the author believes that the choice of a single operating voltage point (say, 480 kV) is unnecessary, and that a bank engineered for dual operation at 480 and 240 kV will be the best solution to the ATLAS problem

  3. Numerical and experimental investigation of geometric parameters in projection welding

    DEFF Research Database (Denmark)

    Kristensen, Lars; Zhang, Wenqi; Bay, Niels

    2000-01-01

    parameters by numerical modeling and experimental studies. SORPAS, an FEM program for numerical modeling of resistance welding, is developed as a tool to help in the phase of product design and process optimization in both spot and projection welding. A systematic experimental investigation of projection...... on the numerical and experimental investigations of the geometric parameters in projection welding, guidelines for selection of the geometry and material combinations in product design are proposed. These will be useful and applicable to industry.......Resistance projection welding is widely used for joining of workpieces with almost any geometric combination. This makes standardization of projection welding impossible. In order to facilitate industrial applications of projection welding, systematic investigations are carried out on the geometric...

  4. Experimental study of the vortex-induced vibration of drilling risers under the shear flow with the same shear parameter at the different Reynolds numbers.

    Science.gov (United States)

    Liangjie, Mao; Qingyou, Liu; Shouwei, Zhou

    2014-01-01

    A considerable number of studies for VIV under the uniform flow have been performed. However, research on VIV under shear flow is scarce. An experiment for VIV under the shear flow with the same shear parameter at the two different Reynolds numbers was conducted in a deep-water offshore basin. Various measurements were obtained by the fiber bragg grating strain sensors. Experimental data were analyzed by modal analysis method. Results show several valuable features. First, the corresponding maximum order mode of the natural frequency for shedding frequency is the maximum dominant vibration mode and multi-modal phenomenon is appeared in VIV under the shear flow, and multi-modal phenomenon is more apparent at the same shear parameter with an increasing Reynolds number under the shear flow effect. Secondly, the riser vibrates at the natural frequency and the dominant vibration frequency increases for the effect of the real-time tension amplitude under the shear flow and the IL vibration frequency is the similar with the CF vibration frequency at the Reynolds number of 1105 in our experimental condition and the IL dominant frequency is twice the CF dominant frequency with an increasing Reynolds number. In addition, the displacement trajectories at the different locations of the riser appear the same shape and the shape is changed at the same shear parameter with an increasing Reynolds number under the shear flow. The diagonal displacement trajectories are observed at the low Reynolds number and the crescent-shaped displacement trajectories appear with an increasing Reynolds number under shear flow in the experiment.

  5. Experimental study of the vortex-induced vibration of drilling risers under the shear flow with the same shear parameter at the different Reynolds numbers.

    Directory of Open Access Journals (Sweden)

    Mao Liangjie

    Full Text Available A considerable number of studies for VIV under the uniform flow have been performed. However, research on VIV under shear flow is scarce. An experiment for VIV under the shear flow with the same shear parameter at the two different Reynolds numbers was conducted in a deep-water offshore basin. Various measurements were obtained by the fiber bragg grating strain sensors. Experimental data were analyzed by modal analysis method. Results show several valuable features. First, the corresponding maximum order mode of the natural frequency for shedding frequency is the maximum dominant vibration mode and multi-modal phenomenon is appeared in VIV under the shear flow, and multi-modal phenomenon is more apparent at the same shear parameter with an increasing Reynolds number under the shear flow effect. Secondly, the riser vibrates at the natural frequency and the dominant vibration frequency increases for the effect of the real-time tension amplitude under the shear flow and the IL vibration frequency is the similar with the CF vibration frequency at the Reynolds number of 1105 in our experimental condition and the IL dominant frequency is twice the CF dominant frequency with an increasing Reynolds number. In addition, the displacement trajectories at the different locations of the riser appear the same shape and the shape is changed at the same shear parameter with an increasing Reynolds number under the shear flow. The diagonal displacement trajectories are observed at the low Reynolds number and the crescent-shaped displacement trajectories appear with an increasing Reynolds number under shear flow in the experiment.

  6. Experimental investigation of cutting parameters influence on ...

    Indian Academy of Sciences (India)

    429–445. c Indian Academy of Sciences ... This is employed for the manufacture of helicopter rotor blades and forging dies. ..... bij Xi X j +. ∑k i=1 bii X2 i ,. (2) where b0 is the free term of the regression equation, the .... Figure 1. Effect of cutting speed on surface roughness at various feed rates. ..... Experimental run order.

  7. Numerical Experimentation to Develop Design and Operational Parameters for Skimming Wells: A Case Study of the Chaj Doab of Punjab, Pakistan

    Directory of Open Access Journals (Sweden)

    Muhammad Aslam

    2015-07-01

    Full Text Available In the present study, MODFLOW-MT3D groundwater model was employed to perform numerical experimentation to develop design and operational parameters for SW (Skimming Wells based on hydrogeology and groundwater salinity conditions of Chaj Doab, Punjab, Pakistan. Numerical experimentation resulted in: (i a 1-strainer SW with discharge of 14 l/s (litres per second and penetration of 30% resulted in more saltwater upconing at 8 hours/day well operation compared to that occurred at 4 hours/day operation; (ii a 1-strainer well with penetration of 30% and operation of 8 hours/day caused higher saltwater upconing at 14 l/s discharge compared to that at 9 l/s discharge; (iii a 4-strainer well with penetration of 30% and operation of 8 hours/day also caused more saltwater upconing at 14 l/s well discharge compared to that at 9 l/s discharge. Similar trend was found for a 8- strainer well; and (iv 1- or 4- or 8-strainer well with 30-60% penetration, 9-14 l/s discharge and 4-8 hours/day operation could provide pumped groundwater of salinity less than 1000 ppm. Considering hydro-chemical performance and costs of wells, a 4-strainer well with 30% penetration, 9- 14 l/s discharge and 4-8 hours/day operation is recommended to skim groundwater of salinity less than 1000 ppm in Chaj Doab of Punjab, Pakistan

  8. Optimising imaging parameters in experimental spiral CT

    International Nuclear Information System (INIS)

    Tiitola, M.; Vehmas, T.; Kivisaari, R.P.; Kivisaari, L.

    1997-01-01

    Purpose: This in vitro study was conducted to analyse lesion detection and relative radiation exposure in different CT techniques. Material and Methods: We used a plastic phantom (12 x 8 x 2 cm) containing holes filled with air or fluid of varying densities to simulate lesions. This was imaged with Siemens Somatom Plus S and GE High Speed Advantage units. We varied table feeds (3 and 6 mm/s in Siemens and 3 and 4.5 mm/s in GE) and increments (2 mm and 4 mm) while keeping collimation at 3 mm. The SmartScan program of GE and the reformating algorithm of Siemens were also analysed. To evaluate the different methods, the phatnom lesions were counted by 3 observers. Radiation exposures associated with each technique were also measured. Results: The images reformatted to a coronal direction were significantly inferior (p<0.01) to those in other techniques. The use of SmartScan did not influence lesion detection, nor did changes in pitch or increment. Spiral and non-spiral techniques proved to be equal. Radiation exposure was lowest when a greater pitch or the SmartScan program was used. Conclusion: Radiation exposure in CT can be limited without significantly impairing the image quality by using low-dose techniques. Reformatting to a coronal direction should be used with care as it debases the image quality. (orig.)

  9. Parameter space of experimental chaotic circuits with high-precision control parameters

    Energy Technology Data Exchange (ETDEWEB)

    Sousa, Francisco F. G. de; Rubinger, Rero M. [Instituto de Física e Química, Universidade Federal de Itajubá, Itajubá, MG (Brazil); Sartorelli, José C., E-mail: sartorelli@if.usp.br [Universidade de São Paulo, São Paulo, SP (Brazil); Albuquerque, Holokx A. [Departamento de Física, Universidade do Estado de Santa Catarina, Joinville, SC (Brazil); Baptista, Murilo S. [Institute of Complex Systems and Mathematical Biology, SUPA, University of Aberdeen, Aberdeen (United Kingdom)

    2016-08-15

    We report high-resolution measurements that experimentally confirm a spiral cascade structure and a scaling relationship of shrimps in the Chua's circuit. Circuits constructed using this component allow for a comprehensive characterization of the circuit behaviors through high resolution parameter spaces. To illustrate the power of our technological development for the creation and the study of chaotic circuits, we constructed a Chua circuit and study its high resolution parameter space. The reliability and stability of the designed component allowed us to obtain data for long periods of time (∼21 weeks), a data set from which an accurate estimation of Lyapunov exponents for the circuit characterization was possible. Moreover, this data, rigorously characterized by the Lyapunov exponents, allows us to reassure experimentally that the shrimps, stable islands embedded in a domain of chaos in the parameter spaces, can be observed in the laboratory. Finally, we confirm that their sizes decay exponentially with the period of the attractor, a result expected to be found in maps of the quadratic family.

  10. [Experimental studies of micromotor headpieces].

    Science.gov (United States)

    Kanaev, V F; Repin, V A

    1982-01-01

    Experimental studies of handpieces for micromotors have been performed to make more precise their operating parameters. The special stand has been used for the measurements of the following data: head temperature, power losses in handpieces at no-load, and operating power required for machining by means of spherical burrs. The experimental results made it possible to specify more exactly the range of handpiece rotational speeds and to select optimum loads under reliability testing.

  11. EXPERIMENTAL STUDY IN NATURAL CONVECTION

    African Journals Online (AJOL)

    PROF. BARTH EKWEME

    The study of thermal and ventilation parameters, obtained in a transient, laminar solar chimney of reduced dimensions, (1 < m <3) m with a square collector (side = 2m) is presented. Experimental measurements has been made to determine the temperature of the absorber and the fluid in the collector, it is shown that at the ...

  12. Molecular modeling and experimental studies on structure and NMR parameters of 9-benzyl-3,6-diiodo-9H-carbazole

    DEFF Research Database (Denmark)

    Radula-Janik, Klaudia; Kupka, Teobald; Ejsmont, Krzysztof

    2015-01-01

    A combined experimental and theoretical study has been performed on 9-benzyl-3,6-diiodo-9H-carbazole. Experimental X-ray (100.0 K) and room-temperature 13C NMR studies were supported by advanced density functional theory (DFT) calculations. The non relativistic structure optimization was performed...... and the 13C nuclear magnetic shieldings were predicted at the relativistic level of theory using the Zeroth Order Regular Approximation (ZORA). The changes in the benzene and pyrrole rings compared to the unsubstituted carbazole or the parent molecules were discussed in terms of aromaticity changes using...... the harmonic oscillator model of aromaticity (HOMA) and the nucleus independent chemical shift (NICS) indexes. Theoretical relativistic calculations of chemical shifts of carbons C3 and C6, directly bonded to iodine atoms, produced a reasonable agreement with experiment (initial deviation from experiment of 41...

  13. Justification for parameters of a dynamic stabilizer of the experimental stand mobile unit in studying of active rotational working tools of tiller machines

    Directory of Open Access Journals (Sweden)

    Vladimir F. Kupryashkin

    2017-03-01

    Full Text Available Introduction: The article deals with design options and technological modes of the dynamic stabilizer of the experimental stand mobile unit for studying tillage machine active rotating work tools. Based on theoretical and experimental studies, the possibility the movable module instability was discovered. This negatively affects on implementing the experiment program trough the especific method. The need in engineering solutions for the defect correction is shown. In addition, the authors consider the structural features and characteristics of the used devices for providing the stabilization of the movable module in the study of active rotating work tools of tillage machines. An electromagnetic brake dynamic stabilizer in the structure of the existing rolling module was proposed as an engineering device. Materials and Methods: A theoretical study of rolling module stability, based on synthesis of basic regulations and laws of mechanics related to active rotating work tools was conducted. As a result of the theoretical research, a design scheme of movable module loading was created. This scheme includes the design features and structural power factors. Results: A database representing the settings of power specification in the motion stability determining the mobile unit was created. Further use of the database values allow supporting the most optimal location of the electromagnetic brake with its design options. Discussion and Conclusions: The research of the electromagnetic brake in a mobile unit promoted stabilizing the unit movement, increased the frequency of its use and provided data that are more precise during experiments.

  14. Experimental parameters research for oxides of synthesis by microwave

    Energy Technology Data Exchange (ETDEWEB)

    Ratmann, Ezequiel Cafumann; Moreira, Mário Lúcio; Ratmann, Cristiane Raubach; Cava, Sergio da Silva, E-mail: ezequiel.ratmann@gmail.com [Universidade Federal de Pelotas (UFPEL), RS (Brazil)

    2016-07-01

    Full text: The objective of this study is to investigate the influence of experimental parameter of zinc oxide (ZnO) in the structural and optical properties obtained by a microwave-assisted solvo thermal method. The method consists in obtaining ZnO at temperatures from 90 - 140 °C and subsequently characterized structurally and verify possible variations in optical characteristics through photoluminescence measurements. The characterizations were performed by X-ray diffraction, scanning electron microscopy and photoluminescence measurements. The results show that the change in temperature of synthesis does not affect the crystal structure of ZnO. The photoluminescence measurements show a shift only in the sample obtained at 120 °C temperature. A more detailed study on the 120°C system is necessary to be able to say that the effect observed in the optical property is due to the method of synthesis. References: [1] S. R. Pinnell, D. Fairhurst, R. Gillies, M. A. Mitchnick, and N. Kollias. Microfine zinc oxide is a superior sunscreen ingredient to microfine titanium dioxide, Dermatologic surgery, vol. 26, no. 4, pp. 309-314, 2000; [2] Efracio M. Flores. Influência do solvente nas propriedades estruturais e ópticas de sistema ZnO@ZnS core-shell, obtidos pelo método solvotérmico assistido por microondas. Dissertação de Mestrado. 2015. (author)

  15. Experimental evaluation of a modal parameter based system identification procedure

    Science.gov (United States)

    Yu, Minli; Feng, Ningsheng; Hahn, Eric J.

    2016-02-01

    Correct modelling of the foundation of a rotor bearing foundation system (RBFS) is an invaluable asset for the balancing and efficient running of turbomachinery. Numerical experiments have shown that a modal parameter based identification approach could be feasible for this purpose but there is a lack of experimental verification of the suitability of such a modal approach for even the simplest systems. In this paper the approach is tested on a simple experimental rig comprising a clamped horizontal bar with lumped masses. It is shown that apart from damping, the proposed approach can identify reasonably accurately the relevant modal parameters of the rig; and that the resulting equivalent system can predict reasonably well the frequency response of the rig. Hence, the proposed approach shows promise but further testing is required, since application to identifying the foundation of an RBFS involves the additional problem of accurately obtaining the force excitation from motion measurements.

  16. Study of the effect of some of the experimental parameters on the x-ray fluorescence determination of traces of hafnia in high purity zirconia

    International Nuclear Information System (INIS)

    Qurbani, J.M.; Khanna, P.P.; Agrawal, R.M.

    1974-01-01

    The effect of the following parameters : (i) analytical lines HfLsub(αsub(1)) or HfLsub(βsub(1,6)) or HfLsub(βsub(2)) (ii) detectors - scintillation or gas flow proportional (iii) collimators - fine or coarse (iv) x-ray tube voltage, current and power (v) order of diffraction : I or II of analysing crystal LiF (200), on the precision of the results and the sensitivity of the method in the x-ray fluorescence determination of traces of hafnia in high purity zirconia, has been studied. Philips semiautomatic x-ray spectrometer PW 1220 with associated equipment has been used. Synthetic standards containing HfO 2 in the range 20 ppm to 1 % in ZrO 2 , presented as double layer pellets have been used. LiF (200) analysing crystal, tungsten target x-ray tube, automatic pulse height selection and pulse height discrimination were used in all the cases. The set - 'HfLsub(βsub(1,6)) analytical line, fine collimator and gas flow proportional counter detector' - gave the best performance. (author)

  17. Statistical approach for uncertainty quantification of experimental modal model parameters

    DEFF Research Database (Denmark)

    Luczak, M.; Peeters, B.; Kahsin, M.

    2014-01-01

    Composite materials are widely used in manufacture of aerospace and wind energy structural components. These load carrying structures are subjected to dynamic time-varying loading conditions. Robust structural dynamics identification procedure impose tight constraints on the quality of modal models...... represent different complexity levels ranging from coupon, through sub-component up to fully assembled aerospace and wind energy structural components made of composite materials. The proposed method is demonstrated on two application cases of a small and large wind turbine blade........ This paper aims at a systematic approach for uncertainty quantification of the parameters of the modal models estimated from experimentally obtained data. Statistical analysis of modal parameters is implemented to derive an assessment of the entire modal model uncertainty measure. Investigated structures...

  18. Experimental study of a model and parameters calculating annual mean atmospheric dispersion factor for a nuclear power plant to be build in coastal site

    International Nuclear Information System (INIS)

    Hu Erbang; Chen Jiayi; Zhang Maoshuan; Gao Zhanrong; Yao Rentai; Jia Peirong; Qiao Qingdang

    1999-01-01

    The author tries to develop a new model calculating annual mean atmospheric dispersion factor for a nuclear power plant to be build in coastal site based on field experiments. This model considers not only the difference between shore ward and off-shore but also the comprehensive effect of following factors: mixed layer and thermal internal boundary layer, mixing release and variation of diffusion parameters due to the distance from coast and so on. The various parameters needed in the model are obtained from the field atmospheric experiments done on the NPP site during 1995∼1996. There dimension joint frequency is got from wind and temperature measurements at 4 heights of a tower of 100 m; diffusion parameters shore ward and off-shore from turbulent measurement and wind tunnel simulation test; the parameters relative to sea and land breeze and thermal internal boundary layer are obtained from tests with low altitude radiosonde and lost balloon at 3 sites during two periods of Summer and Winter. Finally a comparison of the results given by this model and commonly used model provided by relative guides is done. The comparison shows that about 1 times under estimation is found for the maximum of annual mean atmospheric dispersion factor in common model because the effect from thermal internal boundary layer and other factors are neglected

  19. ANOVA parameters influence in LCF experimental data and simulation results

    Directory of Open Access Journals (Sweden)

    Vercelli A.

    2010-06-01

    Full Text Available The virtual design of components undergoing thermo mechanical fatigue (TMF and plastic strains is usually run in many phases. The numerical finite element method gives a useful instrument which becomes increasingly effective as the geometrical and numerical modelling gets more accurate. The constitutive model definition plays an important role in the effectiveness of the numerical simulation [1, 2] as, for example, shown in Figure 1. In this picture it is shown how a good cyclic plasticity constitutive model can simulate a cyclic load experiment. The component life estimation is the subsequent phase and it needs complex damage and life estimation models [3-5] which take into account of several parameters and phenomena contributing to damage and life duration. The calibration of these constitutive and damage models requires an accurate testing activity. In the present paper the main topic of the research activity is to investigate whether the parameters, which result to be influent in the experimental activity, influence the numerical simulations, thus defining the effectiveness of the models in taking into account of all the phenomena actually influencing the life of the component. To obtain this aim a procedure to tune the parameters needed to estimate the life of mechanical components undergoing TMF and plastic strains is presented for commercial steel. This procedure aims to be easy and to allow calibrating both material constitutive model (for the numerical structural simulation and the damage and life model (for life assessment. The procedure has been applied to specimens. The experimental activity has been developed on three sets of tests run at several temperatures: static tests, high cycle fatigue (HCF tests, low cycle fatigue (LCF tests. The numerical structural FEM simulations have been run on a commercial non linear solver, ABAQUS®6.8. The simulations replied the experimental tests. The stress, strain, thermal results from the thermo

  20. Study of the experimental parameters associated to the determination of residual macro stresses in stainless steel tubes, through x-ray diffraction method

    International Nuclear Information System (INIS)

    Guimaraes, L.R.

    1990-01-01

    The basic principles related to the determination of residual macro stresses by X-rays diffractometry are present, whereas different techniques associated with the respective experimental errors are discussed. The residual stresses in two 304 L stainless steel tubes were measured using three models of diffractometers, Rigaku SG-8, Jeol JDX-11PA and Rigaku Strainflex. The measured values of stresses as well as the reproducibilities are examined. The suitability of peak location method, by fitting three data points to the parabolic function, is discussed through values of position and intensity obtained by two of the above diffractometers. (author)

  1. Study of the experimental parameters associated to the determination of residual macro stresses in stainless steel tubes through x-rays diffraction method

    International Nuclear Information System (INIS)

    Guimaraes, L.R.

    1990-01-01

    The basic principles related to the determination of residual macro stresses by X-rays diffractometry are present, whereas different techniques associated with the respective experimental errors are discussed. The residual stresses in two 304 L stainless steel tubes were measured using three models of diffractometers, Rigaku SG-8, Jeol JDX-11PA and Rigaku Strainflex. The measured values of stresses as well as the reproducibilities are examined. The suitability of peak location method, by fitting three data points to the parabolic function, is discussed through values of position and intensity obtained by two of the above diffractometers. (author)

  2. Impact parameter determination in experimental analysis using neural network

    International Nuclear Information System (INIS)

    Haddad, F.; David, C.; Freslier, M.; Aichelin, J.; Haddad, F.; Hagel, K.; Li, J.; Mdeiwayeh, N.; Natowitz, J.B.; Wada, R.; Xiao, B.

    1997-01-01

    A neural network is used to determine the impact parameter in 40 Ca + 40 Ca reactions. The effect of the detection efficiency as well as the model dependence of the training procedure have been studied carefully. An overall improvement of the impact parameter determination of 25 % is obtained using this technique. The analysis of Amphora 40 Ca+ 40 Ca data at 35 MeV per nucleon using a neural network shows two well separated classes of events among the selected 'complete' events. (authors)

  3. Study of castor oil polyurethane - poly(methyl methacrylate semi-interpenetrating polymer network (SIPN reaction parameters using a 2³ factorial experimental design

    Directory of Open Access Journals (Sweden)

    Fernanda Oliveira Vieira da Cunha

    2004-12-01

    Full Text Available In this work was employed a 2³ factorial experiment design to evaluate the castor oil polyurethane-poly(methyl methacrylate semi-IPN synthesis. The reaction parameters used as independent variables were NCO/OH molar ratio, polyurethane polymerization time and methyl methacrylate (MMA content. The semi-IPNs were cured over 28 h using two thermal treatments. The polymers were characterized by infrared and Raman spectroscopy, thermal analysis and swelling profiles in n-hexane. The glass transition temperature (Tg and the swelling were more affect by the NCO/OH molar ratio variation. The semi-IPNs showed Tg from - 27 to - 6 °C and the swelling range was from 3 to 22%, according to the crosslink density. The IPN mechanical properties were dependent on the cure temperature and MMA content in it. Lower elastic modulus values were observed in IPNs cured at room temperature.

  4. Study of the experimental parameters for the determination of Ca, Cr, Cu, Fe, Mn and Ni on nuclear grade UO2 by X-ray fluorescence technique

    International Nuclear Information System (INIS)

    Salvador, V.L.R.

    1982-01-01

    An analytical method for the simultaneous determinations of low concentrations of Ca, Cr, Cu, Fe, Mn and Ni on the nuclear grade UO 2 by X-ray fluorescence technique, without the use of chemical treatment, is described. The optimization of the experimental conditions was established on the X-ray fluorescence spectrometer and a low limit of detection (4 - 7 μg/gU) was achieved which satisfies the requirement in the nuclear fuel specification. The samples were prepared in the form of double layer pressed pellets using boric acid as a binding agent. The characteristic first order K sub(α) line intensity of each minor component was measured and the values of its concentrations were deduced using respective standard calibrations curves. The precision, accuracy and acceptability of the method were determined for all elements. The values of the precision are in the range of 2 - 10% and the accuracy are lower than 7%. (Author) [pt

  5. Optimization of Experimental Model Parameter Identification for Energy Storage Systems

    Directory of Open Access Journals (Sweden)

    Rosario Morello

    2013-09-01

    Full Text Available The smart grid approach is envisioned to take advantage of all available modern technologies in transforming the current power system to provide benefits to all stakeholders in the fields of efficient energy utilisation and of wide integration of renewable sources. Energy storage systems could help to solve some issues that stem from renewable energy usage in terms of stabilizing the intermittent energy production, power quality and power peak mitigation. With the integration of energy storage systems into the smart grids, their accurate modeling becomes a necessity, in order to gain robust real-time control on the network, in terms of stability and energy supply forecasting. In this framework, this paper proposes a procedure to identify the values of the battery model parameters in order to best fit experimental data and integrate it, along with models of energy sources and electrical loads, in a complete framework which represents a real time smart grid management system. The proposed method is based on a hybrid optimisation technique, which makes combined use of a stochastic and a deterministic algorithm, with low computational burden and can therefore be repeated over time in order to account for parameter variations due to the battery’s age and usage.

  6. Parameter and state estimation of experimental chaotic systems using synchronization

    Science.gov (United States)

    Quinn, John C.; Bryant, Paul H.; Creveling, Daniel R.; Klein, Sallee R.; Abarbanel, Henry D. I.

    2009-07-01

    We examine the use of synchronization as a mechanism for extracting parameter and state information from experimental systems. We focus on important aspects of this problem that have received little attention previously and we explore them using experiments and simulations with the chaotic Colpitts oscillator as an example system. We explore the impact of model imperfection on the ability to extract valid information from an experimental system. We compare two optimization methods: an initial value method and a constrained method. Each of these involves coupling the model equations to the experimental data in order to regularize the chaotic motions on the synchronization manifold. We explore both time-dependent and time-independent coupling and discuss the use of periodic impulse coupling. We also examine both optimized and fixed (or manually adjusted) coupling. For the case of an optimized time-dependent coupling function u(t) we find a robust structure which includes sharp peaks and intervals where it is zero. This structure shows a strong correlation with the location in phase space and appears to depend on noise, imperfections of the model, and the Lyapunov direction vectors. For time-independent coupling we find the counterintuitive result that often the optimal rms error in fitting the model to the data initially increases with coupling strength. Comparison of this result with that obtained using simulated data may provide one measure of model imperfection. The constrained method with time-dependent coupling appears to have benefits in synchronizing long data sets with minimal impact, while the initial value method with time-independent coupling tends to be substantially faster, more flexible, and easier to use. We also describe a method of coupling which is useful for sparse experimental data sets. Our use of the Colpitts oscillator allows us to explore in detail the case of a system with one positive Lyapunov exponent. The methods we explored are easily

  7. The Effect of Blood Loss in the Presence and Absence of Severe Soft Tissue Injury on Hemodynamic and Metabolic Parameters; an Experimental study

    Directory of Open Access Journals (Sweden)

    Ali Mohammad Moradi

    2014-09-01

    Full Text Available Introduction: The effect of severe soft tissue injury on the severity of hemorrhagic shock is still unknown. Therefore, the present study was aimed to determine hemodynamic and metabolic changes in traumatic/hemorrhagic shock in an animal model. Methods: Forty male rats were randomly divided into 4 equal groups including sham, hemorrhagic shock, soft tissue injury, and hemorrhagic shock + soft tissue injury groups. The changes in blood pressure, central venous pressure (CVP level, acidity (pH, and base excess were dynamically monitored and comparedsented. Results: Mean arterial blood pressure decreased significantly in hemorrhagic shock (df: 12; F=10.9; p<0.001 and severe soft tissue injury + hemorrhagic shock (df: 12; F=11.7; p<0.001 groups 15 minutes and 5 minutes after injury, respectively. A similar trend was observed in CVP in severe soft tissue injury + hemorrhagic shock group (df: 12; F=8.9; p<0.001. After 40 minutes, pH was significantly lower in hemorrhagic shock (df: 12; F=6.8; p=0.009 and severe soft tissue injury + hemorrhagic shock (df: 12; F=7.9; p=0.003 groups. Base excess changes during follow ups have a similar trend. (df: 12; F=11.3; p<0.001. Conclusion: The results of this study have shown that the effect of hemorrhage on the decrease of mean arterial blood pressure, CVP, pH, and base excess is the same in the presence or absence of soft tissue injury.

  8. Multivariate study of parameters in the determination of pesticide residues in apple by headspace solid phase microextraction coupled to gas chromatography-mass spectrometry using experimental factorial design.

    Science.gov (United States)

    Abdulra'uf, Lukman Bola; Tan, Guan Huat

    2013-12-15

    Solid-phase microextraction (SPME) is a solvent-less sample preparation method which combines sample preparation, isolation, concentration and enrichment into one step. In this study, multivariate strategy was used to determine the significance of the factors affecting the solid phase microextraction of pesticide residues (fenobucarb, diazinon, chlorothalonil and chlorpyrifos) using a randomised factorial design. The interactions and effects of temperature, time and salt addition on the efficiency of the extraction of the pesticide residues were evaluated using 2(3) factorial designs. The analytes were extracted with 100 μm PDMS fibres according to the factorial design matrix and desorbed into a gas chromatography-mass spectrometry detector. The developed method was applied for the analysis of apple samples and the limits of detection were between 0.01 and 0.2 μg kg(-)(1), which were lower than the MRLs for apples. The relative standard deviations (RSD) were between 0.1% and 13.37% with average recovery of 80-105%. The linearity ranges from 0.5-50 μg kg(-)(1) with correlation coefficient greater than 0.99. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Damping Factor as a Diagnostic Parameter for Assessment of Osseointegration during the Dental Implant Healing Process: An Experimental Study in Rabbits.

    Science.gov (United States)

    Feng, Sheng-Wei; Ho, Kuo-Ning; Chan, Ya-Hui; Chang, Kai-Jung; Lai, Wei-Yi; Huang, Haw-Ming

    2016-12-01

    The purpose of this study was to evaluate the possibility of using damping factor (DF) analysis to provide additional information on osseointegration of dental implants during the healing period. A total of 30 dental implants were installed in the bilateral femoral condyles of 15 rabbits. A DF analyzer detected with an impulse-forced vibration method and a commercialized dental implant stability analyzer based on resonance frequency (RF) analysis were used to measure the implant stability immediately after implant placement and 1, 2, 4, and 8 weeks post-surgically. Results of DF and RF analyses at different time points were compared with the corresponding osseointegration performance of dental implants via micro-computed tomography (micro-CT), histological and histomorphometrical analysis. The DF values revealed a decrease with time and reached 0.062 ± 0.007 at 8 weeks after implantation, which is almost 50% lower than the initial value. Moreover, highly significant correlations between DF values and bone volume densities (R 2  = 0.9797) and percentages of bone-to-implant contact measured at trabecular bone area (R 2  = 0.9773) were also observed. These results suggested that DF analysis combined with RF analysis results in a more sensitive assessment of changes in the dental implant/bone complex during the healing period than RF analysis alone.

  10. Influence of several experimental parameters on As and Se leaching from coal fly ash samples

    International Nuclear Information System (INIS)

    Otero-Rey, Jose R.; Mato-Fernandez, Maria J.; Moreda-Pineiro, Jorge; Alonso-Rodriguez, Elia; Muniategui-Lorenzo, Soledad; Lopez-Mahia, Purificacion; Prada-Rodriguez, Dario

    2005-01-01

    Coal fly ash leaching process for As and Se is studied. Environmental parameters such as pH, temperature, solid-liquid ratio, particle size and leaching time are taken into account in order to simulate As and Se leaching process for disposal coal fly ash. Analysis of reference materials was carried out by using of hydride generation coupled to atomic fluorescence spectrometry. Plackett-Burman experimental design is used to know the significative parameters, and Box-Behnken experimental design is used to refine the results obtained for these significative parameters. pH and temperature shown a hardly influence in leaching process. Furthermore, leaching time was also significative. According our results, it may be assumed that percentage of As and Se leaching in experimental conditions tested is relatively low for acidic fly ashes

  11. Investigation on gas medium parameters for an ArF excimer laser through orthogonal experimental design

    Science.gov (United States)

    Song, Xingliang; Sha, Pengfei; Fan, Yuanyuan; Jiang, R.; Zhao, Jiangshan; Zhou, Yi; Yang, Junhong; Xiong, Guangliang; Wang, Yu

    2018-02-01

    Due to complex kinetics of formation and loss mechanisms, such as ion-ion recombination reaction, neutral species harpoon reaction, excited state quenching and photon absorption, as well as their interactions, the performance behavior of different laser gas medium parameters for excimer laser varies greatly. Therefore, the effects of gas composition and total gas pressure on excimer laser performance attract continual research studies. In this work, orthogonal experimental design (OED) is used to investigate quantitative and qualitative correlations between output laser energy characteristics and gas medium parameters for an ArF excimer laser with plano-plano optical resonator operation. Optimized output laser energy with good pulse to pulse stability can be obtained effectively by proper selection of the gas medium parameters, which makes the most of the ArF excimer laser device. Simple and efficient method for gas medium optimization is proposed and demonstrated experimentally, which provides a global and systematic solution. By detailed statistical analysis, the significance sequence of relevant parameter factors and the optimized composition for gas medium parameters are obtained. Compared with conventional route of varying single gas parameter factor sequentially, this paper presents a more comprehensive way of considering multivariables simultaneously, which seems promising in striking an appropriate balance among various complicated parameters for power scaling study of an excimer laser.

  12. clinical and experimental study

    OpenAIRE

    Tornow, Christoph

    2011-01-01

    Posterior capsule opacity (PCO) is a frequent complication in extracapsular cataract extraction in conjunction with an intraocular lens implant. Different studies have shown that a reduction in PCO frequency can be achieved via a number of factors. Lens design is a significant criterion in this process. In this study, two multifocal intraocular lenses (MIOLs) were compared. The design of these lenses differed due to their varying optical principles. They are the refractive MIOL A...

  13. Comet Halley, parameter study I

    International Nuclear Information System (INIS)

    Huebner, W.F.; Fikani, M.M.

    1982-06-01

    To aid in defining a mission to comet P/Halley, its inner coma is simulated by a computer program that models time-dependent chemical reactions in a radially and isentropically expanding gas, taking into account attenuation of solar ultraviolet radiation in the subsolar direction. Column density predictions are based on intelligently selected combinations of poorly known values for nucleus parameters that include size, visual albedo, and infrared emissivity. Only one chemical composition and a minor modification of it are considered here; the dust-to-gas ratio in this model is zero. Although the somewhat optimistically volatile composition chosen here favors a smaller nucleus, a mean nuclear radius of only 0.5 km is unlikely. No significant increase of molecular column density is predicted by this model as a spacecraft approaches, once it is less than a few 10 4 km from the nucleus. Predictions are made for various heliocentric distances of interest for comet missions and for ground observations

  14. Experimental critical parameters of plutonium metal cylinders flooded with water

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-07-01

    Forty-nine critical configurations are reported for experiments involving arrays of 3 kg plutonium metal cylinders moderated and reflected by water. Thirty-four of these describe systems assembled in the laboratory, while 15 others are derived critical parameters inferred from 46 subcritical cases. The arrays included 2x2xN, N = 2, 3, 4, and 5, in one program and 3x3x3 configurations in a later study. All were three-dimensional, nearly square arrays with equal horizontal lattice spacings but a different vertical lattice spacing. Horizontal spacings ranged from units in contact to 180 mm center-to-center; and vertical spacings ranged from about 80 mm to almost 400 mm center-to-center. Several nearly-equilateral 3x3x3 arrays exhibit an extremely sensitive dependence upon horizontal separation for identical vertical spacings. A line array of unreflected and essentially unmoderated canned plutonium metal units appeared to be well subcritical based on measurements made to assure safety during the manual assembly operations. All experiments were performed at two widely separated times in the mid-1970s and early 1980s under two programs at the Rocky Flats Plant`s Critical Mass Laboratory.

  15. Experimental critical parameters of plutonium metal cylinders flooded with water

    International Nuclear Information System (INIS)

    1996-07-01

    Forty-nine critical configurations are reported for experiments involving arrays of 3 kg plutonium metal cylinders moderated and reflected by water. Thirty-four of these describe systems assembled in the laboratory, while 15 others are derived critical parameters inferred from 46 subcritical cases. The arrays included 2x2xN, N = 2, 3, 4, and 5, in one program and 3x3x3 configurations in a later study. All were three-dimensional, nearly square arrays with equal horizontal lattice spacings but a different vertical lattice spacing. Horizontal spacings ranged from units in contact to 180 mm center-to-center; and vertical spacings ranged from about 80 mm to almost 400 mm center-to-center. Several nearly-equilateral 3x3x3 arrays exhibit an extremely sensitive dependence upon horizontal separation for identical vertical spacings. A line array of unreflected and essentially unmoderated canned plutonium metal units appeared to be well subcritical based on measurements made to assure safety during the manual assembly operations. All experiments were performed at two widely separated times in the mid-1970s and early 1980s under two programs at the Rocky Flats Plant's Critical Mass Laboratory

  16. A sEMG model with experimentally based simulation parameters.

    Science.gov (United States)

    Wheeler, Katherine A; Shimada, Hiroshima; Kumar, Dinesh K; Arjunan, Sridhar P

    2010-01-01

    A differential, time-invariant, surface electromyogram (sEMG) model has been implemented. While it is based on existing EMG models, the novelty of this implementation is that it assigns more accurate distributions of variables to create realistic motor unit (MU) characteristics. Variables such as muscle fibre conduction velocity, jitter (the change in the interpulse interval between subsequent action potential firings) and motor unit size have been considered to follow normal distributions about an experimentally obtained mean. In addition, motor unit firing frequencies have been considered to have non-linear and type based distributions that are in accordance with experimental results. Motor unit recruitment thresholds have been considered to be related to the MU type. The model has been used to simulate single channel differential sEMG signals from voluntary, isometric contractions of the biceps brachii muscle. The model has been experimentally verified by conducting experiments on three subjects. Comparison between simulated signals and experimental recordings shows that the Root Mean Square (RMS) increases linearly with force in both cases. The simulated signals also show similar values and rates of change of RMS to the experimental signals.

  17. Experimental study of virtual impactors

    International Nuclear Information System (INIS)

    Yule, T.J.; Broniarck, C.G.

    1979-01-01

    Virtual impactors are currently being used in a number of instruments to separate an aerosol into different size ranges. The virtual impactor is a variation of the standard impactor in which the impaction surface is replaced by an orifice into which particles can pass and be collected or counted. We have made an experimental study of the collection characteristics of virtual impactors. The parameters varied included: acceleration nozzle-to-collection probe distance, the ratio of the collection probe-to-acceleration nozzle diameters, and the ratio of collection probe-to-inlet flows. Measurements were also made with different collection probe geometries. It was found that it is possible to parameterize much of the data by introduction of the Stokes number and an effective minor flow collection efficiency. One disadvantage of the virtual impactor is that in the transition region particles are collected on the inside walls of the collection probe near the probe tip. The amount that is collected is a sensitive function of the probe geometry

  18. Experimental Verification of Statistically Optimized Parameters for Low-Pressure Cold Spray Coating of Titanium

    Directory of Open Access Journals (Sweden)

    Damilola Isaac Adebiyi

    2016-06-01

    Full Text Available The cold spray coating process involves many process parameters which make the process very complex, and highly dependent and sensitive to small changes in these parameters. This results in a small operational window of the parameters. Consequently, mathematical optimization of the process parameters is key, not only to achieving deposition but also improving the coating quality. This study focuses on the mathematical identification and experimental justification of the optimum process parameters for cold spray coating of titanium alloy with silicon carbide (SiC. The continuity, momentum and the energy equations governing the flow through the low-pressure cold spray nozzle were solved by introducing a constitutive equation to close the system. This was used to calculate the critical velocity for the deposition of SiC. In order to determine the input temperature that yields the calculated velocity, the distribution of velocity, temperature, and pressure in the cold spray nozzle were analyzed, and the exit values were predicted using the meshing tool of Solidworks. Coatings fabricated using the optimized parameters and some non-optimized parameters are compared. The coating of the CFD-optimized parameters yielded lower porosity and higher hardness.

  19. Influence of experimental parameters on the microencapsulation of a photopolymerizable phase.

    Science.gov (United States)

    Pernot, J M; Brun, H; Pouyet, B; Sergent, M; Phan-Tan-Luu, R

    1993-01-01

    Conditions of microencapsulation by in situ polycondensation, using melamine-formaldehyde as wall material, are influenced by the chemical nature of the core to encapsulate. In our study concerning the encapsulation of a photopolymerizable phase containing an electrically charged compound, it was necessary to modify the experimental process to obtain capsules of good quality. We used the factorial design method of screening by utilization of an asymmetric matrix, according to the collapsing principle of Addleman. The advantage of this method is that it allows determination of the simultaneous influences of the 11 experimental parameters involved in this preparation. The calculation method can be applied to more than two levels for some of the factors. The continuously varying parameters were altered between two extreme levels, chosen to allow encapsulation. For discontinuous factors, such as the molecular weight of the modifying system or nature of the aminoplast, we used the commercially available compounds, respectively three and four kinds. The results of the obtained capsules were determined by comparing microphotographic pictures. With 16 experiments we found four more factors influencing quality of capsules. We also determined the most favourable levels for the other seven parameters. The results allowed us to find optimal conditions in the experimental field. We obtained capsules of a satisfactory quality for this purpose, using only minimum experimentation.

  20. Experimental and numerical investigation of plasma parameters in the magnetosheath

    Directory of Open Access Journals (Sweden)

    Dobreva Polya

    2018-01-01

    Full Text Available We investigate the behaviour of the plasma parameters in the magnetosheath in a case when Interball-1 satellite stayed in the magnetosheath, crossing the tail magnetopause. In our analysis we apply the numerical magnetosheath-magnetosphere model as a theoretical tool. The bow shock and the magnetopause are self-consistently determined in the process of the solution. The flow in the magnetosheath is governed by the Euler equations of compressible ideal gas. The magnetic field in the magnetosphere is calculated by a variant of the Tsyganenko model, modified to account for an asymmetric magnetopause. Also, the magnetopause currents in Tsyganenko model are replaced by numericaly calulated ones. Measurements from WIND spacecraft are used as a solar wind monitor. The results demonstrate a good agreement between the model-calculated and measured values of the parameters under investigation.

  1. A Parameter Study of Localization

    Directory of Open Access Journals (Sweden)

    Sandor Stephen Mester

    1996-01-01

    Full Text Available Extensive work has been done on the vibration characteristics of perfectly periodic structures. Disorder in the periodic pattern has been found to lead to localization in one-dimensional periodic structures. It is important to understand localization because it causes energy to be concentrated near the disorder and may cause an overestimation of structural damping. A numerical study is conducted to obtain a better understanding of localization. It is found that any mode, even the first, can localize due to the presence of small imperfections.

  2. Copper(II) complex with 6-methylpyridine-2-carboxyclic acid: Experimental and computational study on the XRD, FT-IR and UV-Vis spectra, refractive index, band gap and NLO parameters.

    Science.gov (United States)

    Altürk, Sümeyye; Avcı, Davut; Başoğlu, Adil; Tamer, Ömer; Atalay, Yusuf; Dege, Necmi

    2018-02-05

    Crystal structure of the synthesized copper(II) complex with 6-methylpyridine-2-carboxylic acid, [Cu(6-Mepic) 2 ·H 2 O]·H 2 O, was determined by XRD, FT-IR and UV-Vis spectroscopic techniques. Furthermore, the geometry optimization, harmonic vibration frequencies for the Cu(II) complex were carried out by using Density Functional Theory calculations with HSEh1PBE/6-311G(d,p)/LanL2DZ level. Electronic absorption wavelengths were obtained by using TD-DFT/HSEh1PBE/6-311G(d,p)/LanL2DZ level with CPCM model and major contributions were determined via Swizard/Chemissian program. Additionally, the refractive index, linear optical (LO) and non-nonlinear optical (NLO) parameters of the Cu(II) complex were calculated at HSEh1PBE/6-311G(d,p) level. The experimental and computed small energy gap shows the charge transfer in the Cu(II) complex. Finally, the hyperconjugative interactions and intramolecular charge transfer (ICT) were studied by performing of natural bond orbital (NBO) analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Experimental studies of electron capture

    International Nuclear Information System (INIS)

    Pedersen, E.H.

    1983-01-01

    This thesis discusses the main results of recent experimental studies of electron capture in asymmetric collisions. Most of the results have been published, but the thesis also contains yet unpublished data, or data presented only in unrefereed conference proceedings. The thesis aims at giving a coherent discussion of the understanding of the experimental results, based first on simple qualitative considerations and subsequently on quantitative comparisons with the best theoretical calculations currently available. (Auth.)

  4. Experimental setimeted of the some parameters of the conveyor belts

    Directory of Open Access Journals (Sweden)

    Marasová Daniela

    2001-12-01

    Full Text Available At present one of the most spread methods able to solve non-linear problems of the mechanics is theis the finite-element method. When solving problems of hyperelasticity by the finite-element method (FEM for introducing the input materials' constants of the body investigated, best - thought-out Money-Rivlin's theory is used. It is the method describing the behaviour of hyper-elastic materials with large elastic (reversible deformations. For the description of behaviour of the hyperelastic materials, can be used also the development from more members, comprising 5 or 9 materials' constants. The problem with the determining the hyperelastic materials' characteristics is one of the most important factors effecting the accuracy of the calculation result. The material's constants A and B are det-rmined experimentally from the practical tests, e.g.tensile, compressive or other and have to meet certain conditions. The paper shows the possibility how to determinate these matherials´ charakteris-tics and their verification by the mathematical model ANSYS.

  5. Qualitative Parameters of Practice during University Studies

    Science.gov (United States)

    Stasiunaitiene, Egle; Norkute, Odeta

    2011-01-01

    In this article, relevance of practice during university studies is highlighted, as well as the main stages of its organisation, qualitative parameters, as well as criteria and indicators that validate them are defined. Discussion on the idea that taking into consideration qualitative parameters of organising practice as a component of studies…

  6. EBTS: DESIGN AND EXPERIMENTAL STUDY

    International Nuclear Information System (INIS)

    PIKIN, A.; ALESSI, J.; BEEBE, E.; KPONOU, A.; PRELEC, K.; KUZNETSOV, G.; TIUNOV, M.

    2000-01-01

    Experimental study of the BNL Electron Beam Test Stand (EBTS), which is a prototype of the Relativistic Heavy Ion Collider (RHIC) Electron Beam Ion Source (EBIS), is currently underway. The basic physics and engineering aspects of a high current EBIS implemented in EBTS are outlined and construction of its main systems is presented. Efficient transmission of a 10 A electron beam through the ion trap has been achieved. Experimental results on generation of multiply charged ions with both continuous gas and external ion injection confirm stable operation of the ion trap

  7. Experimental studies of morphology development

    International Nuclear Information System (INIS)

    Whitton, J.L.

    1986-01-01

    This contribution is a resume of the approximately eight years of experimental investigation of ion beam-induced modification of metal surfaces. The aim, from the beginning, was to make a detailed series of experiments with well defined controllable parameters in an attempt to establish the mechanism responsible for the production of the topographical features observed so frequently on ion-bombarded surfaces of metals. Typically, for the initial system, 40 keV argon ions directed on to copper, the sputtering yield is fairly constant from normal angle of incidence to about 30 0 , rising fairly smoothly to a maximum at 80 0 , then dropping rapidly to zero at around 82 0 . A very strong grain orientation effect was observed in the early experiments. (Auth.)

  8. Experimental studies of nuclear astrophysics

    International Nuclear Information System (INIS)

    He Jianjun; Zhou Xiaohong; Zhang Yuhu

    2013-01-01

    Nuclear astrophysics is an interdisciplinary subject combining micro-scale nuclear physics and macro-scale astrophysics. Its main aims are to understand the origin and evolution of the elements in the universe, the time scale of stellar evolution, the stellar environment and sites, the energy generation of stars from thermonuclear processes and its impact on stellar evolution and the mechanisms driving astrophysical phenomena, and the structure and property of compact stars. This paper presents the significance and current research status of nuclear astrophysics; we introduce some fundamental concepts, the nuclear physics input parameters required by certain astrophysics models, and some widely-used experimental approaches in nuclear astrophysics research. The potential and feasibility of research in this field using China’s current and planned large-scale scientific facilities are analyzed briefly. Finally, the prospects of the establishing a deep underground science and engineering laboratory in China are envisaged. (authors)

  9. Propagation of a channelized debris-flow: experimental investigation and parameters identification for numerical modelling

    Science.gov (United States)

    Termini, Donatella

    2013-04-01

    Recent catastrophic events due to intense rainfalls have mobilized large amount of sediments causing extensive damages in vast areas. These events have highlighted how debris-flows runout estimations are of crucial importance to delineate the potentially hazardous areas and to make reliable assessment of the level of risk of the territory. Especially in recent years, several researches have been conducted in order to define predicitive models. But, existing runout estimation methods need input parameters that can be difficult to estimate. Recent experimental researches have also allowed the assessment of the physics of the debris flows. But, the major part of the experimental studies analyze the basic kinematic conditions which determine the phenomenon evolution. Experimental program has been recently conducted at the Hydraulic laboratory of the Department of Civil, Environmental, Aerospatial and of Materials (DICAM) - University of Palermo (Italy). The experiments, carried out in a laboratory flume appositely constructed, were planned in order to evaluate the influence of different geometrical parameters (such as the slope and the geometrical characteristics of the confluences to the main channel) on the propagation phenomenon of the debris flow and its deposition. Thus, the aim of the present work is to give a contribution to defining input parameters in runout estimation by numerical modeling. The propagation phenomenon is analyzed for different concentrations of solid materials. Particular attention is devoted to the identification of the stopping distance of the debris flow and of the involved parameters (volume, angle of depositions, type of material) in the empirical predictive equations available in literature (Rickenmanm, 1999; Bethurst et al. 1997). Bethurst J.C., Burton A., Ward T.J. 1997. Debris flow run-out and landslide sediment delivery model tests. Journal of hydraulic Engineering, ASCE, 123(5), 419-429 Rickenmann D. 1999. Empirical relationships

  10. Three-dimensional FEM model of FBGs in PANDA fibers with experimentally determined model parameters

    Science.gov (United States)

    Lindner, Markus; Hopf, Barbara; Koch, Alexander W.; Roths, Johannes

    2017-04-01

    A 3D-FEM model has been developed to improve the understanding of multi-parameter sensing with Bragg gratings in attached or embedded polarization maintaining fibers. The material properties of the fiber, especially Young's modulus and Poisson's ratio of the fiber's stress applying parts, are crucial for accurate simulations, but are usually not provided by the manufacturers. A methodology is presented to determine the unknown parameters by using experimental characterizations of the fiber and iterative FEM simulations. The resulting 3D-Model is capable of describing the change in birefringence of the free fiber when exposed to longitudinal strain. In future studies the 3D-FEM model will be employed to study the interaction of PANDA fibers with the surrounding materials in which they are embedded.

  11. Identification of nuclear plant temperatures. Feedback parameters using experimental data

    International Nuclear Information System (INIS)

    Abdel Hamid, Sayed.

    1981-09-01

    This work is concerned with the identification of the fuel and moderator reactivity feedback coefficients of a Pressurized Water Reactor (PWR) using actual measurements. The main aim of this study is to examine the possibility to use a simplified model representing the reactor dynamics, which can be simulated on minicomputer and to supply an identification algorithm to get the feedback coefficients of PWR. The theoretical model of a PWR is built from the space independent reactor kinetics equation associated with six delayed neutron groups equations, as well as twelve equations describe the heat balance for the fuel and the moderator inside the reactor core, assuming that the core is composed from six successive axial zones. The reactor is externally perturbed by moving its control rods, and the corresponding changes in power and temperatures are recorded. The mathematical model has been solved numerically using fifth order Runge-Kutta integration technique by special developed package using Solar 16-40 computer (64 K memory size). As an identification algorithm, the Nelder-Mead Simplex method has been used to minimize the sum of the squares of the differences between measured and calculated reactor power. Hence, the feedback coefficients have been identified from off-line calculations

  12. Vegetation growth parameters and leaf temperature: Experimental results from a six plots green roofs' system

    International Nuclear Information System (INIS)

    Ferrante, Patrizia; La Gennusa, Maria; Peri, Giorgia; Rizzo, Gianfranco; Scaccianoce, Gianluca

    2016-01-01

    The paper provides a contribution for populating database of three physical parameters needed to model energy performance of buildings with green roofs: “coverage ratio” (σ_f), leaf area index (LAI) and leaf temperature (T_f). On purpose, six plant species were investigated experimentally: Phyla nordiflora, Aptenia lancifolia, Mesembryanthenum barbatus, Gazania nivea, Gazania uniflora, and Sedum. Proper ranges of the cited parameters have been found for each species. The here indicated ranges of σ_f values refer to different growth levels of the species in the same lapse of time, that is four months. Single measured LAI values are also reported for the same plants. As for the T_f (upper and lower layer), ranges of revealed temperatures refer to those detected from 10:30 a.m. to 16:30 p.m. of a selected day. Additionally, the dependence of T_f on climatic parameters was investigated. A linear equation resulted the best fitting curve for all experimental T_f data and the corresponding solar radiation data (with autocorrelation coefficients between 0.80 and 0.98). Furthermore, the effect potentially produced on building energy consumption by these species was analyzed using a simulation tool. Estimated cooling energy savings range approximately between 8% and 20% depending on adopted plants. - Highlights: • Green roof modeling requires the knowledge of various physical parameters. • Coverage ratio, leaf area index and leaves temperatures were measured for six species. • A tentative correlation between leaf temperature and climatic parameters was shown. • A correlation between LAI and coverage ratio was checked and discussed. • Potential effects of studied species on building energy consumption were investigated.

  13. Calculation of kinetic parameters of Caliban metallic core experimental reactor from stochastic neutron measurements

    Energy Technology Data Exchange (ETDEWEB)

    Casoli, P.; Authier, N.; Baud, J. [Commissariat a l' energie Atomique, Centre de Valduc, 21120 Is-sur-Tille (France)

    2009-07-01

    Several experimental devices are operated by the Criticality and Neutron Science Research Department of the CEA Valduc Laboratory. One of these is the metallic core reactor Caliban. The knowledge of the fundamental kinetic parameters of the reactor is very useful, indeed necessary, to the operator. The purpose of this study was to develop and perform experiments allowing to determinate some of these parameters. The prompt neutron decay constant and particularly its value at criticality can be measured with reactor noise techniques such as the interval-distribution, the Feynman variance-to-mean, and the Rossi-{alpha} methods. By introducing the Nelson number, the effective delayed neutron fraction and the average neutron lifetime can also be calculated with the Rossi-{alpha} method. Subcritical, critical, and even supercritical experiments were performed. With the Rossi-{alpha} technique, it was found that the prompt neutron decay constant at criticality was (6.02*10{sup 5} {+-} 9%). Experiments also brought out the limitations of the used experimental parameters. (authors)

  14. A combined experimental and analytical approach for interface fracture parameters of dissimilar materials in electronic packages

    International Nuclear Information System (INIS)

    Kay, N.R.; Ghosh, S.; Guven, I.; Madenci, E.

    2006-01-01

    This study concerns the development of a combined experimental and analytical technique to determine the critical values of fracture parameters for interfaces between dissimilar materials in electronic packages. This technique utilizes specimens from post-production electronic packages. The mechanical testing is performed inside a scanning electron microscope while the measurements are achieved by means of digital image correlation. The measured displacements around the crack tip are used as the boundary conditions for the analytical model to compute the energy release rate. The critical energy release rate values obtained from post-production package specimens are obtained to be lower than those laboratory specimens

  15. An experimental analysis of illumination intensity and temperature dependency of photovoltaic cell parameters

    International Nuclear Information System (INIS)

    Cuce, Erdem; Cuce, Pinar Mert; Bali, Tulin

    2013-01-01

    Highlights: • R sh is rather sensitive to the variations in T c . • For higher G values, G ∗ is not affected from the variations in light intensity. • Ideality factor decreases linearly with increasing T c . • A linear decrease of R s and R sh has been observed with increasing T c . • Fill factor increases exponentially with G while it decreases linearly with T c . - Abstract: It is well known that accurate knowledge of photovoltaic cell parameters from the measured current–voltage characteristics is of vital importance for the quality control and the performance assessment of photovoltaic cells/modules. Although many attempts have been made so far for a thorough analysis of cell parameters, there are still significant discrepancies between the previously published results. In this regard, a detailed investigation of cell parameters through a comprehensive experimental and statistical work is important to elucidate the aforementioned contradictions. Therefore in the present work, effects of two main environmental factors on performance parameters of mono-crystalline and poly-crystalline silicon photovoltaic modules have been experimentally investigated. The experiments have been carried out under a calibrated solar simulator for various intensity levels and cell temperatures in the range 200–500 W/m 2 and 15–60 °C, respectively. The results indicated that light intensity has a dominant effect on current parameters. Photocurrent, short circuit current and maximum current increase linearly with increasing intensity level. A new term, solar intensity coefficient, has been defined first time to characterize the solar radiation dependency of current parameters. On the other hand, it has been observed that cell temperature has a dramatic effect on voltage parameters. Open circuit voltage and maximum voltage considerably decrease with increasing cell temperature. Temperature coefficients of voltage parameters have been calculated for each case. Shunt

  16. Changes in the basic experimental parameters of capillary gas chromatography in the 20th century.

    Science.gov (United States)

    Berezkin, V G; Viktorova, E N

    2003-01-24

    Studies of qualitative changes in capillary gas chromatography are of significant practical and scientific interest. This paper analyzes the evolution of the most important experimental chromatographic parameters over the last three decades and is based on the use of a new approach to scientometrical research that is referred to as applied scientometry. One essential feature of this approach is that it looks at the entire contents of each paper rather than only taking account its title, abstract. and references (as is typical for conventional scientometry). In this paper, we monitor how the most important chromatographic parameters, such as column length and diameter, layer thickness, stationary liquid phases, separation temperature mode. etc., have been evolving over the period 1970-2000. We used data from the following journals: Chromatographia, Journal of Chromatography, and Journal of High Resolution Chromatography and Chromatography Communications.

  17. Experimental studies of minienvironment types

    International Nuclear Information System (INIS)

    Eissler, W.; Schneider, H.

    1994-01-01

    Various minienvironment types are available offering different features at quite different costs. MEISSNER+WURST performed in its JESSI project experimental tests to examine the isolation capabilities and the recovery time of minienvironments and the influence of manual handling and maintenance on the minienvironment cleanliness. An isolation factor up to 1 million was measured in the experiments. The Custom Tailored Minienvironment has the best protection against external and internal particle sources. Critical points in the design and the installation of minienvironments were identified. The results of air flow visualization studies were confirmed by airflow simulations. The result of the studies allow a classification of minienvironment types according to their cleanliness achievements

  18. On the design of experimental separation processes for maximum accuracy in the estimation of their parameters

    International Nuclear Information System (INIS)

    Volkman, Y.

    1980-07-01

    The optimal design of experimental separation processes for maximum accuracy in the estimation of process parameters is discussed. The sensitivity factor correlates the inaccuracy of the analytical methods with the inaccuracy of the estimation of the enrichment ratio. It is minimized according to the design parameters of the experiment and the characteristics of the analytical method

  19. Optimizing experimental parameters for the projection requirement in HAADF-STEM tomography

    Energy Technology Data Exchange (ETDEWEB)

    Aveyard, R., E-mail: r.a.aveyard@tudelft.nl [Department of Imaging Physics, Delft University of Technology, 2628CJ Delft (Netherlands); Zhong, Z.; Batenburg, K.J. [Centrum Wiskunde and Informatica, Science Park 123, NL-1098 XG Amsterdam (Netherlands); Rieger, B., E-mail: b.rieger@tudelft.nl [Department of Imaging Physics, Delft University of Technology, 2628CJ Delft (Netherlands)

    2017-06-15

    Highlights: • The extent to which HAADF-STEM meets the projection requirement has been studied. • Multislice simulations used to model beam propagation and study signal linearity. • Propagation in crystalline and amorphous materials considered. • Optimal experimental set-up for the projection requirement is discussed. - Abstract: Tomographic reconstruction algorithms offer a means by which a tilt-series of transmission images can be combined to yield a three dimensional model of the specimen. Conventional reconstruction algorithms assume that the measured signal is a linear projection of some property, typically the density, of the material. Here we report the use of multislice simulations to investigate the extent to which this assumption is met in HAADF-STEM imaging. The use of simulations allows for a systematic survey of a range of materials and microscope parameters to inform optimal experimental design. Using this approach it is demonstrated that the imaging of amorphous materials is in good agreement with the projection assumption in most cases. Images of crystalline specimens taken along zone-axes are found to be poorly suited for conventional linear reconstruction algorithms due to channelling effects which produce enhanced intensities compared with off-axis images, and poor compliance with the projection requirement. Off-axis images are found to be suitable for reconstruction, though they do not strictly meet the linearity requirement in most cases. It is demonstrated that microscope parameters can be selected to yield improved compliance with the projection requirement.

  20. Optimizing experimental parameters for the projection requirement in HAADF-STEM tomography

    International Nuclear Information System (INIS)

    Aveyard, R.; Zhong, Z.; Batenburg, K.J.; Rieger, B.

    2017-01-01

    Highlights: • The extent to which HAADF-STEM meets the projection requirement has been studied. • Multislice simulations used to model beam propagation and study signal linearity. • Propagation in crystalline and amorphous materials considered. • Optimal experimental set-up for the projection requirement is discussed. - Abstract: Tomographic reconstruction algorithms offer a means by which a tilt-series of transmission images can be combined to yield a three dimensional model of the specimen. Conventional reconstruction algorithms assume that the measured signal is a linear projection of some property, typically the density, of the material. Here we report the use of multislice simulations to investigate the extent to which this assumption is met in HAADF-STEM imaging. The use of simulations allows for a systematic survey of a range of materials and microscope parameters to inform optimal experimental design. Using this approach it is demonstrated that the imaging of amorphous materials is in good agreement with the projection assumption in most cases. Images of crystalline specimens taken along zone-axes are found to be poorly suited for conventional linear reconstruction algorithms due to channelling effects which produce enhanced intensities compared with off-axis images, and poor compliance with the projection requirement. Off-axis images are found to be suitable for reconstruction, though they do not strictly meet the linearity requirement in most cases. It is demonstrated that microscope parameters can be selected to yield improved compliance with the projection requirement.

  1. Radiometric parameters in freshwater samples of Centro Experimental Aramar (CTMSP/Brazil)

    Energy Technology Data Exchange (ETDEWEB)

    Moraes, Marco Antonio P.V. [Laboratorio Radioecologico (LARE), Ipero, SP (Brazil). Dept. de Seguranca Nuclear; Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    Experimental results are described obtained with gamma spectrometry, alpha and beta gross counts, liquid scintillation and fluorometry techniques for the measurement of background radiation in surface water samples, collected in Centro Experimental Aramar and surroundings, from 1988 to 2009. The estimated average background radiation concentrations in water samples in this region are low, related to the low level detection limits of the techniques, and indicates good water quality parameters, and low interference in the environment in Centro Experimental Aramar and region. (author)

  2. Study and analysis of drift chamber parameters

    International Nuclear Information System (INIS)

    Martinez Laso, L.

    1988-01-01

    The present work deals mainly with drift chambers. In the first chapter a summary of drift chamber properties is presented. The information has been collected from the extensive bibliography available in this field. A very simple calculation procedure of drift chamber parameters has been developed and is presented in detail in the second chapter. Some prototypes have been made following two geometries (multidrift chamber and Z-chambers). Several installations have been used for test and calibration of these prototypes. A complete description of these installations is given in the third chapter. Cosmic rays, beta particles from a Ru106 radiactive source and a test beam in the WA (West Area) of SPS at CERN have been used for experimental purposes. The analysis and the results are described for the different setups. The experimental measurements have been used to produce a complete cell parametrization (position as function of drift time) and to obtain spatial resolution values (in the range of 200-250 um). Experimental results are in good agreement with numerical calculations. (Author)

  3. Theoretical and experimental determination of K - and L -shell x-ray relaxation parameters in Ni

    Science.gov (United States)

    Guerra, M.; Sampaio, J. M.; Parente, F.; Indelicato, P.; Hönicke, P.; Müller, M.; Beckhoff, B.; Marques, J. P.; Santos, J. P.

    2018-04-01

    Fluorescence yields (FY) for the Ni K and L shells were determined by a theoretical and an experimental group within the framework of the International Initiative on X-ray Fundamental Parameters (FPs) collaboration. Coster-Kronig (CK) parameters were also measured for the L shell of Ni. Theoretical calculations of the same parameters were performed using the Dirac-Fock method, including relativistic and QED corrections. The experimental values for the FY and CK were determined at the PTB laboratory in the synchrotron radiation facility BESSY II, Berlin, Germany, and are compared to the corresponding calculated values.

  4. Experimental and analytical determination of stability parameters for a balloon tethered in a wind

    Science.gov (United States)

    Redd, L. T.; Bennett, R. M.; Bland, S. R.

    1973-01-01

    Experimental and analytical techniques for determining stability parameters for a balloon tethered in a steady wind are described. These techniques are applied to a particular 7.64-meter-long balloon, and the results are presented. The stability parameters of interest appear as coefficients in linearized stability equations and are derived from the various forces and moments acting on the balloon. In several cases the results from the experimental and analytical techniques are compared and suggestions are given as to which techniques are the most practical means of determining values for the stability parameters.

  5. Characterization of an erbium doped fiber amplifier starting from its experimental parameters

    International Nuclear Information System (INIS)

    Bello J, M.; Kuzin, E.A.; Ibarra E, B.; Tellez G, R.

    2007-01-01

    In this paper we describe a method to characterize the gain of an erbium-doped fiber amplifier (EDFA) through the numerical simulation of the signal beam along the amplifier. The simulation is based on a model constituted by the propagation and rate equations for an erbium-doped fiber. The manipulation of these equations allows us to regroup the parameters present in an EDFA, which we have named the A, B, C, D parameters, and they can be obtained experimentally from an erbium-doped fiber. Experimental results show that the measurement of these parameters allow us to estimate with very good correspondence the amplifier gain. (Author)

  6. Experimental study of neoclassical currents

    International Nuclear Information System (INIS)

    Zarnstorff, M.C.; Prager, S.C.

    1985-05-01

    A detailed experimental study is presented of the bootstrap and Pfirsch-Schlueter currents that are predicted by neoclassical transport theory. In a toroidal octupole, on magnetic surfaces within the separatrix, the observed parallel plasma currents are in excellent quantitative agreement with neoclassical theory with regard to the spatial structure (along a magnetic surface), collisionality dependence and toroidal magnetic field dependence. On magnetic surfaces outside the separatrix, the ion portion of the parallel current is in agreement with neoclassical theory but the electron parallel current is observed to obtain a unidirectional component which deviates from and exceeds the theoretical prediction

  7. Electrodialytic desalination of brackish water: determination of optimal experimental parameters using full factorial design

    Science.gov (United States)

    Gmar, Soumaya; Helali, Nawel; Boubakri, Ali; Sayadi, Ilhem Ben Salah; Tlili, Mohamed; Amor, Mohamed Ben

    2017-12-01

    The aim of this work is to study the desalination of brackish water by electrodialysis (ED). A two level-three factor (23) full factorial design methodology was used to investigate the influence of different physicochemical parameters on the demineralization rate (DR) and the specific power consumption (SPC). Statistical design determines factors which have the important effects on ED performance and studies all interactions between the considered parameters. Three significant factors were used including applied potential, salt concentration and flow rate. The experimental results and statistical analysis show that applied potential and salt concentration are the main effect for DR as well as for SPC. The effect of interaction between applied potential and salt concentration was observed for SPC. A maximum value of 82.24% was obtained for DR under optimum conditions and the best value of SPC obtained was 5.64 Wh L-1. Empirical regression models were also obtained and used to predict the DR and the SPC profiles with satisfactory results. The process was applied for the treatment of real brackish water using the optimal parameters.

  8. Comparison of Instrumentation and Control Parameters Based on Simulation and Experimental Data for Reactor TRIGA PUSPATI

    International Nuclear Information System (INIS)

    Anith Khairunnisa Ghazali; Mohd Sabri Minhat

    2015-01-01

    Reactor TRIGA PUSPATI (RTP) undergoes safe operation for more than 30 years and the only research reactor in Malaysia. The main safety feature of Instrumentation and Control (I and C) system design is such that any failure in the electronic, or its associated components, does not lead to an uncontrolled rate of reactivity. There are no best models for RTP simulation was designed for study and research. Therefore, the comparison for I&C parameters are very essential, to design the best RTP model using MATLAB/ Simulink as close as the RTP. The simulation of TRIGA reactor type already develop using desktop reactor simulator such as Personal Computer Transient Analyzer (PCTRAN). The experimental data from RTP and simulation of PCTRAN shows some similarities and differences due to certain limitation. Currently, the structured RTP simulation was designed using MATLAB and Simulink tool that consist of ideal fission chamber, controller, control rod position, height to worth and RTP model. The study on this paper focus on comparison between real data from RTP and simulation result from PCTRAN on I&C parameters such as water level, fuel temperature, bulk temperature, power rated and rod position. The error analysis due to some similarities and differences of I&C parameters shall be obtained and analysed. The result will be used as reference for proposed new structured of RTP model. (author)

  9. Investigating dynamic parameters in HWZPR ased on the experimental and calculated results

    Energy Technology Data Exchange (ETDEWEB)

    Nasrazadani, Zahra; Behfamia, Manochehar; Khosandi, Jamshid; Mirvakili, Mohammad [Reactors Research School, Nuclear Science And Technology Research Institute, Atomic Energy Organization of Iran, Esfahan (Iran, Islamic Republic of)

    2016-10-15

    The neutron decay constant, α, and effective delayed neutron fraction, β{sub eff}, are important parameters for the control of the dynamic behavior of nuclear reactors. For the heavy water zero power reactor (HWZPR), this document describes the measurements of the neutron decay constant by noise analysis methods, including variance to mean (VTM) ratio and endogenous pulse source (EPS) methods. The measured α is successively used to determine the experimental value of the effective delayed neutron fraction as well. According to the experimental results, β{sub eff} of the HWZPR reactor under study is equal to 7.84e-3. This value is finally used to validate the calculation of the effective delayed neutron fraction by the Monte Carlo methods that are discussed in the document. Using the Monte Carlo N-Particle (MCNP)-4C code, a β{sub eff} value of 7.58e-3 was obtained for the reactor under study. Thus, the relative difference between the β{sub eff} values determined experimentally and by Monte Carlo methods was estimated to be < 4%.

  10. Experimental evaluation of a quasi-modal parameter based rotor foundation identification technique

    Science.gov (United States)

    Yu, Minli; Liu, Jike; Feng, Ningsheng; Hahn, Eric J.

    2017-12-01

    Correct modelling of the foundation of rotating machinery is an invaluable asset in model-based rotor dynamic study. One attractive approach for such purpose is to identify the relevant modal parameters of an equivalent foundation using the motion measurements of rotor and foundation at the bearing supports. Previous research showed that, a complex quasi-modal parameter based system identification technique could be feasible for this purpose; however, the technique was only validated by identifying simple structures under harmonic excitation. In this paper, such identification technique is further extended and evaluated by identifying the foundation of a numerical rotor-bearing-foundation system and an experimental rotor rig respectively. In the identification of rotor foundation with multiple bearing supports, all application points of excitation forces transmitted through bearings need to be included; however the assumed vibration modes far outside the rotor operating speed cannot or not necessary to be identified. The extended identification technique allows one to identify correctly an equivalent foundation with fewer modes than the assumed number of degrees of freedom, essentially by generalising the technique to be able to handle rectangular complex modal matrices. The extended technique is robust in numerical and experimental validation and is therefore likely to be applicable in the field.

  11. Program for parameter studies of steam generators

    International Nuclear Information System (INIS)

    Mathisen, R.P.

    1982-11-01

    R2-GEN is a computer code for stationary thermal parameter studies of steam generators. The geometry and data are valid for Ringhals-2 generators. Subroutines and relevant calculations are included. The program is based on a heterogeneous flow model and some applications on tubes with varying contamination are presented. (G.B.)

  12. Experimental and computational study of thaumasite structure

    Energy Technology Data Exchange (ETDEWEB)

    Scholtzová, Eva, E-mail: Eva.Scholtzova@savba.sk [Institute of Inorganic Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, 845 36 Bratislava (Slovakia); Kucková, Lenka; Kožíšek, Jozef [Department of Physical Chemistry, Institute of Physical Chemistry and Chemical Physics, Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, 812 37 Bratislava (Slovakia); Pálková, Helena [Institute of Inorganic Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, 845 36 Bratislava (Slovakia); Tunega, Daniel [Institute of Inorganic Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, 845 36 Bratislava (Slovakia); Institute for Soil Science, University of Natural Resources and Life Sciences, Peter-Jordanstrasse 82, A-1190 Wien (Austria)

    2014-05-01

    The structure of thaumasite has been studied experimentally by means of a single crystal X-ray diffraction and FTIR methods, and theoretically using density functional theory (DFT) method. Very good agreement was achieved between calculated and experimental structural parameters. In addition, calculations offered the refinement of the positions of the hydrogen atoms. The detailed analysis of the hydrogen bonds existing in the thaumasite structure has been performed. Several types of hydrogen bonds have been classified. The water molecules coordinating Ca{sup 2+} cation act as proton donors in moderate O-H···O hydrogen bonds formed with CO₃⁻²and SO₄⁻² anions. The multiple O-H···O hydrogen bonds exist among water molecules themselves. Finally, relatively weak hydrogen bonds form water molecules with the OH groups from the coordination sphere of the Si(OH)₆⁻² anion. Further, calculated vibrational spectrum allowed complete assignment of all vibrational modes which are not available from the experimental spectrum that has a complex structure with overlapped bands, especially below 1500 cm⁻¹. Highlights: • The thaumasite structure was studied experimentally and using DFT method. • We used DFT method for the refinement of the positions of hydrogen atoms. • A detailed analysis of the hydrogen bonds was done. • A complete assignment of all bands to particular types of vibrations was done.

  13. Experimental study of ozone synthesis

    International Nuclear Information System (INIS)

    Garamoon, A A; Elakshar, F F; Nossair, A M; Kotp, E F

    2002-01-01

    A silent discharge ozonizer has been constructed with a design that enables the study of ozone concentration behaviour as a function of different parameters when oxygen used as a working gas. The behaviour of ozone concentration as a function of discharge current density has four characteristic regions. The concentration is enhanced by more than threefold whenever gas pressure is reduced by a factor of two. The flow rate of the working gas is a more effective parameter on ozone concentration than the gas pressure. When the flow rate is kept constant, and the pressure is decreased by 100%, the ozone concentration increases by only 10%. On the other hand, when the flow rate is decreased by 13%, the ozone concentration increases by 200%, whenever the gas pressure is kept constant. The concentration is nearly doubled when the gap space is increased by four times under the same conditions. The length of the discharge region, the thickness and the dielectric constant of the insulating materials are found to have a considerable effect on the generated ozone concentration. Also, the ozone concentration is ten times less when air is used instead of oxygen as a working gas. A maximum efficiency of 185 g/kWh, is obtained for the present system

  14. Experimental Study on radiation myelopathy

    International Nuclear Information System (INIS)

    Kaneko, Itsuo; Matsushima, Hideno; Yamada, Teruyo

    1979-01-01

    Experimental radiation myelopathy was carried out useing rats. This studies were done refering the effect to skin, the body weight, the status of the paralysis and the capillary densities of the cervical cords. The quadriplegia was seen on the animals which were irradiated over 4000 rad. The vacuoal degeneration was observed on the cervical cords which were irradiated over 4000 rad. The capillary densities of gray matter and white matter decreased finally in proportions to the irradiation dose. The vacuoal degeneration was recognized on the cervical cord in which the capillary density decreased to under 70 per cent of normal density. Decrease of the capillary density is seemed to be the one of the cause of the paralysis. (author)

  15. Experimental study and optimization of a solar still

    Energy Technology Data Exchange (ETDEWEB)

    Menguy, G; Chassagne, G; Sfeir, A; Saab, J

    1976-01-01

    The aim of this investigation was to study the influence of different parameters on the operation of a solar still for production of distilled water. These parameters are essentially classified in two categories: external parameters such as solar radiation, ambient temperatures and wind speed; internal parameters such as thermal insulation, water film thickness and the color of the side walls. The experiments were carried out on two identical stills. The effects of the different parameters were investigated by comparing the output of the two stills under different experimental conditions. This study resulted in the development of a simple inexpensive still which can readily be put in practical use in the area.

  16. Procedure for statistical analysis of one-parameter discrepant experimental data

    International Nuclear Information System (INIS)

    Badikov, Sergey A.; Chechev, Valery P.

    2012-01-01

    A new, Mandel–Paule-type procedure for statistical processing of one-parameter discrepant experimental data is described. The procedure enables one to estimate a contribution of unrecognized experimental errors into the total experimental uncertainty as well as to include it in analysis. A definition of discrepant experimental data for an arbitrary number of measurements is introduced as an accompanying result. In the case of negligible unrecognized experimental errors, the procedure simply reduces to the calculation of the weighted average and its internal uncertainty. The procedure was applied to the statistical analysis of half-life experimental data; Mean half-lives for 20 actinides were calculated and results were compared to the ENSDF and DDEP evaluations. On the whole, the calculated half-lives are consistent with the ENSDF and DDEP evaluations. However, the uncertainties calculated in this work essentially exceed the ENSDF and DDEP evaluations for discrepant experimental data. This effect can be explained by adequately taking into account unrecognized experimental errors. - Highlights: ► A new statistical procedure for processing one-parametric discrepant experimental data has been presented. ► Procedure estimates a contribution of unrecognized errors in the total experimental uncertainty. ► Procedure was applied for processing half-life discrepant experimental data. ► Results of the calculations are compared to the ENSDF and DDEP evaluations.

  17. Methodology to estimate parameters of an excitation system based on experimental conditions

    Energy Technology Data Exchange (ETDEWEB)

    Saavedra-Montes, A.J. [Carrera 80 No 65-223, Bloque M8 oficina 113, Escuela de Mecatronica, Universidad Nacional de Colombia, Medellin (Colombia); Calle 13 No 100-00, Escuela de Ingenieria Electrica y Electronica, Universidad del Valle, Cali, Valle (Colombia); Ramirez-Scarpetta, J.M. [Calle 13 No 100-00, Escuela de Ingenieria Electrica y Electronica, Universidad del Valle, Cali, Valle (Colombia); Malik, O.P. [2500 University Drive N.W., Electrical and Computer Engineering Department, University of Calgary, Calgary, Alberta (Canada)

    2011-01-15

    A methodology to estimate the parameters of a potential-source controlled rectifier excitation system model is presented in this paper. The proposed parameter estimation methodology is based on the characteristics of the excitation system. A comparison of two pseudo random binary signals, two sampling periods for each one, and three estimation algorithms is also presented. Simulation results from an excitation control system model and experimental results from an excitation system of a power laboratory setup are obtained. To apply the proposed methodology, the excitation system parameters are identified at two different levels of the generator saturation curve. The results show that it is possible to estimate the parameters of the standard model of an excitation system, recording two signals and the system operating in closed loop with the generator. The normalized sum of squared error obtained with experimental data is below 10%, and with simulation data is below 5%. (author)

  18. Discussion of the experimental methods of the estimation of the reaction impact parameter

    International Nuclear Information System (INIS)

    Muryn, B.; Dziunikowska, K.; Eskreys, A.; Coghen, T.

    1978-01-01

    Two methods of determination of the reaction impact parameter, the one proposed by Webber and other by Henyey and Pumplin, are compared and discussed. It is shown that the lower limits of the impact parameter bsub(L) obtained by means of these methods are comparable and are always very low (approximately < 0.5 fm). On the example of the Henyey - Pumplin method it is argued that the experimentally obtained values bsub(L) may be very unreliable estimates of the reaction impact parameter and that any comparison of different reactions or reactions channels may be meaningless. (author)

  19. Impact of errors in experimental parameters on reconstructed breast images using diffuse optical tomography.

    Science.gov (United States)

    Deng, Bin; Lundqvist, Mats; Fang, Qianqian; Carp, Stefan A

    2018-03-01

    largest deterioration due to cross-talk between signal channels. However, errors in optical images could be effectively controlled when experimental parameters were properly estimated during data acquisition and accounted for in the image processing procedure. Finally, optical images recovered using structural priors were, in general, less susceptible to experimental errors; however, lesion contrasts were more sensitive to errors when tumor locations were used as a priori info. Findings in this simulation study can provide guidelines for system design and operation in optical breast imaging studies.

  20. Inverted annular flow experimental study

    International Nuclear Information System (INIS)

    De Jarlais, G.; Ishii, M.

    1985-04-01

    Steady-state inverted annular flow of Freon 113 in up flow was established in a transparent test section. Using a special inlet configuration consisting of long aspect-ratio liquid nozzles coaxially centered within a heated quartz tube, idealized inverted annular flow initial geometry (cylindrical liquid core surrounded by coaxial annulus of gas) could be established. Inlet liquid and gas flowrates, liquid subcooling, and gas density (using various gas species) were measured and varied systematically. The hydrodynamic behavior of the liquid core, and the subsequent downstream break-up of this core into slugs, ligaments and/or droplets of various sizes, was observed. In general, for low inlet liquid velocities it was observed that after the initial formation of roll waves on the liquid core surface, an agitated region of high surface area, with attendant high momentum and energy transfers, occurs. This agitated region appears to propagate downsteam in a quasi-periodic pattern. Increased inlet liquid flow rates, and high gas annulus flow rates tend to diminish the significance of this agitated region. Observed inverted annular flow (and subsequent downstream flow pattern) hydrodynamic behavior is reported, and comparisons are drawn to data generated by previous experimenters studying post-CHF flow

  1. Experimental Research on The Deformability of a Geological Material: Initial Characterisation and Identification of Parameters

    International Nuclear Information System (INIS)

    Villar, M.V.; Udias, A.; Canamon, I.; Robles, J.

    2006-01-01

    This document reflects the work performed at CIEMAT (Engineered and Geological Barriers Group) in the framework of the RTD Project BTE2002-04244-C02-02 (DEF-NOSAT). The first phase of the project consisted on the selection and characterisation of a geological material fitted for unsaturated triaxial testing. The result obtained during this phase gave place to the selection of a silty clay from Alcala de Henares (Madrid, Spain). Compaction and permeability tests were performed as well as studies on mixtures of this soil with sand. With the selected mixtures (70/30 and 50/50 percent sand/soil) isotropic compression tests were carried out in the saturated sample. The results of these tests have allowed the determination of some of the parameters needed to model the mechanical behaviour of the soil. The report includes also a brief description of a methodology developed in the Department of Applied Mathematics and Computer Methods of the Universidad Politecnica de Madrid for getting these parameters by optimisation of the experimental results, as well as the results obtained. (Author) 25 refs

  2. Experimental Active Vibration Control in Truss Structures Considering Uncertainties in System Parameters

    Directory of Open Access Journals (Sweden)

    Douglas Domingues Bueno

    2008-01-01

    Full Text Available This paper deals with the study of algorithms for robust active vibration control in flexible structures considering uncertainties in system parameters. It became an area of enormous interest, mainly due to the countless demands of optimal performance in mechanical systems as aircraft, aerospace, and automotive structures. An important and difficult problem for designing active vibration control is to get a representative dynamic model. Generally, this model can be obtained using finite element method (FEM or an identification method using experimental data. Actuators and sensors may affect the dynamics properties of the structure, for instance, electromechanical coupling of piezoelectric material must be considered in FEM formulation for flexible and lightly damping structure. The nonlinearities and uncertainties involved in these structures make it a difficult task, mainly for complex structures as spatial truss structures. On the other hand, by using an identification method, it is possible to obtain the dynamic model represented through a state space realization considering this coupling. This paper proposes an experimental methodology for vibration control in a 3D truss structure using PZT wafer stacks and a robust control algorithm solved by linear matrix inequalities.

  3. Experimental rigs for MHD studies

    International Nuclear Information System (INIS)

    Venkataramani, N.; Jayakumar, R.; Iyer, D.R.; Dixit, N.S.

    1976-01-01

    An MHD experimental rig is a miniature MHD installation consisting of basic equipments necessary for specific investigations. Some of the experimental rigs used in the investigations being carried out at the Bhabha Atomic Research Centre, Bombay (India) are dealt with. The experiments included diagnostics and evaluation of materials in seeded combustion plasmas and argon plasmas. The design specifications, schematics and some of the results of the investigations are also mentioned. (author)

  4. Experimental investigation on dependency of interparticle distance in Coulomb crystal on various parameters

    OpenAIRE

    Adachi, Satoshi; Takayanagi, Masahiro; 足立 聡; 高柳 昌弘

    2007-01-01

    Dependency of interparticle distance in Coulomb crystal on various parameters such as plasma density, electron temperature, plasma potential and the Debye length are experimentally investigated. From the investigation, it is found that the interparticle distance is proportional to the Debye length.

  5. Experimental determination of lattice parameters for 2% enriched uranium heavy water reactor cores

    Energy Technology Data Exchange (ETDEWEB)

    Raisic, N; Takac, S; Markovic, H; Bosevski, T [Boris Kidric Institute of Nuclear Sciences Vinca, Belgrade (Yugoslavia)

    1963-04-15

    Systematic measurements of the buckling, infinite multiplication factor and the thermal utilization factor were made on a series of lattices for 2% enriched uranium tubular fuel elements in heavy water. This work represents the first phase of experimental verification of standard theoretical methods used for the determination of reactor parameters.

  6. Experimental studies of the magnetized friction force

    International Nuclear Information System (INIS)

    Fedotov, A. V.; Litvinenko, V. N.; Gaalnander, B.; Lofnes, T.; Ziemann, V.; Sidorin, A.; Smirnov, A.

    2006-01-01

    High-energy electron cooling, presently considered as an essential tool for several applications in high-energy and nuclear physics, requires an accurate description of the friction force which ions experience by passing through an electron beam. Present low-energy electron coolers can be used for a detailed study of the friction force. In addition, parameters of a low-energy cooler can be chosen in a manner to reproduce regimes expected in future high-energy operation. Here, we report a set of dedicated experiments in CELSIUS aimed at a detailed study of the magnetized friction force. Some results of the accurate comparison of experimental data with the friction force formulas are presented

  7. Experimental study on the characteristics of semiconductor opening switch

    CERN Document Server

    Su Jian Cang; Ding Yong Zhong; Song Zhi Min; Ding Zhen Jie; Liu Guo Zhi

    2002-01-01

    An experimental set-up is developed to measure the characteristics of semiconductor opening switch (SOS). The parameters, such as interruption impedance, current int eruption time, voltage gain, pulse duration and energy transfer efficiency, are studied experimentally. The experimental results show that forward pumping time and reverse pumping time are important parameters for semiconductor opening switches. The influences of forward pumping time and reverse pumping time on interruption time, voltage gain, and energy transfer efficiency are obtained. In the interruption process, the impedance variation is divided into three phases: that is rapid increasing phase, slow change phase and completely interruption phase

  8. Technical Note: Using experimentally determined proton spot scanning timing parameters to accurately model beam delivery time.

    Science.gov (United States)

    Shen, Jiajian; Tryggestad, Erik; Younkin, James E; Keole, Sameer R; Furutani, Keith M; Kang, Yixiu; Herman, Michael G; Bues, Martin

    2017-10-01

    To accurately model the beam delivery time (BDT) for a synchrotron-based proton spot scanning system using experimentally determined beam parameters. A model to simulate the proton spot delivery sequences was constructed, and BDT was calculated by summing times for layer switch, spot switch, and spot delivery. Test plans were designed to isolate and quantify the relevant beam parameters in the operation cycle of the proton beam therapy delivery system. These parameters included the layer switch time, magnet preparation and verification time, average beam scanning speeds in x- and y-directions, proton spill rate, and maximum charge and maximum extraction time for each spill. The experimentally determined parameters, as well as the nominal values initially provided by the vendor, served as inputs to the model to predict BDTs for 602 clinical proton beam deliveries. The calculated BDTs (T BDT ) were compared with the BDTs recorded in the treatment delivery log files (T Log ): ∆t = T Log -T BDT . The experimentally determined average layer switch time for all 97 energies was 1.91 s (ranging from 1.9 to 2.0 s for beam energies from 71.3 to 228.8 MeV), average magnet preparation and verification time was 1.93 ms, the average scanning speeds were 5.9 m/s in x-direction and 19.3 m/s in y-direction, the proton spill rate was 8.7 MU/s, and the maximum proton charge available for one acceleration is 2.0 ± 0.4 nC. Some of the measured parameters differed from the nominal values provided by the vendor. The calculated BDTs using experimentally determined parameters matched the recorded BDTs of 602 beam deliveries (∆t = -0.49 ± 1.44 s), which were significantly more accurate than BDTs calculated using nominal timing parameters (∆t = -7.48 ± 6.97 s). An accurate model for BDT prediction was achieved by using the experimentally determined proton beam therapy delivery parameters, which may be useful in modeling the interplay effect and patient throughput. The model may

  9. Numerical and experimental study of the influence of the operational parameters on the formation mechanisms of oxides of nitrogen during the combustion of mixtures of cellulosic and plastic materials; Etude experimentale et numerique de l'influence des parametres operatoires sur les mecanismes de formation des oxydes d'azote lors de la combustion de melanges de materiaux cellulosiques et plastiques

    Energy Technology Data Exchange (ETDEWEB)

    Andzi Barhe, T.

    2004-10-15

    The current thesis was performed within a collaboration between the Laboratoire de Combustion et de Detonique (LCD of the University of Poitiers) and the Laboratoire de Physique et de Chimie d'Environnement (LPCE) of the University of Ouagadougou. It was financed by Agency for Environment and Energy Management (ADEME). The principle object of this study is the optimisation of the combustion process during the incineration of waste. This optimisation is aimed at the reduction of the polluting emissions, principally CO and NO, during the incineration of cellulosic and plastic materials. It involves the analysis of the influence of the operational parameters on the polluting emissions and the control of reaction mechanisms of formation and reduction of these pollutants during the combustion process. Consequently, the study was performed in two parts: an experimental part and a numerical part. The experimental part was realised using a fixed bed counterflow reactor. This setup simulates the combustion within an industrial waste incinerator. The reactor allows the combustion of a vertical layer of waste mixture (wood, cardboard, PET, polyamide) to be followed. Three model mixtures representative of the makeup of household waste were studied in order to determine the influence of the composition of the waste on the emission of pollutants (CO and NO). The obtained results show that this parameter has a practically negligible influence within the tested parameter range. Consequently the formation of pollutants depends on the operating parameters - the equivalence ratio and the temperature. A numerical study of the influence of these parameters in order to show their impact on the mechanisms of pollutant formation and to determine the chemical mechanisms involved in the formation of oxides of nitrogen. The numerical study was performed with software developed at the LCD. This programme based on a detailed chemical model coupled to a simple physical model. It uses the

  10. Study of electroweak parameters at LEP

    International Nuclear Information System (INIS)

    Blum, W.

    1991-10-01

    The measurement of the line shape and asymmetry parameters of the Z 0 in its leptonic and hadronic decays are reviewed. Progress is reported about a considerable increase in measurement accuracy. Several tests of the Standard Model confirm it to better than one per cent. New values for the effective mixing parameter are derived from the line shape parameters averaged over the four LEP experiments. The corresponding limits on the top mass are presented. (orig.)

  11. Experimental kinetic parameters in the thermo-fluid-dynamic modelling of coal combustion

    International Nuclear Information System (INIS)

    Migliavacca, G.; Perini, M.; Parodi, E.

    2001-01-01

    The designing and the optimisation of modern and efficient combustion systems are nowadays frequently based on calculation tools for mathematical modelling, which are able to predict the evolution of the process starting from the first principles of physics. Otherwise, in many cases, specific experimental parameters are needed to describe the specific nature of the materials considered in the calculations. It is especially true in the modelling of coal combustion, which is a complex process strongly dependent on the chemical and physical features of the fuel. This paper describes some experimental techniques used to estimate the fundamental kinetic parameters of coal combustion and shows how this data may be introduced in a model calculation to predict the pollutant emissions from a real scale combustion plant [it

  12. EXPERIMENTAL DETERMINATION OF DOUBLE VIBE FUNCTION PARAMETERS IN DIESEL ENGINES WITH BIODIESEL

    Directory of Open Access Journals (Sweden)

    Radivoje B Pešić

    2010-01-01

    Full Text Available A zero-dimensional, one zone model of engine cycle for steady-state regimes of engines and a simplified procedure for indicator diagrams analysis have been developed at the Laboratory for internal combustion engines, fuels and lubricants of the Faculty of Mechanical Engineering in Kragujevac. In addition to experimental research, thermodynamic modeling of working process of diesel engine with direct injection has been presented in this paper. The simplified procedure for indicator diagrams analysis has been applied, also. The basic problem, a selection of shape parameters of double Vibe function used for modeling the engine operation process, has been solved. The influence of biodiesel fuel and engine working regimes on the start of combustion, combustion duration and shape parameter of double Vibe was determined by a least square fit of experimental heat release curve.

  13. Experimental estimations of the kinetics parameters of the IBR-2M reactor by stochastic noises

    International Nuclear Information System (INIS)

    Pepelyshev, Yu.N.; Tajybov, L.A.; Garibov, A.A.; Mekhtieva, R.N.

    2012-01-01

    Experimental investigations of stochastic fluctuations of pulse energy of the IBR-2M reactor have been carried out which allowed us to obtain some of the parameters of the reactor kinetics. At different levels of average power a sequence of values of pulse energy was recorded with the calculation of the distribution parameters. An ionization chamber with boron installed near the active zone was used as a neutron detector. The research results allowed us to estimate the average lifetime of prompt neutrons τ = (6.53±0.2)·10 -8 s, absolute power of the reactor and intensity of the source of spontaneous neutrons S sp ≤(6.72±0.12)·10 6 s -1 . It was shown that the experimental results are close to the calculated ones

  14. Experimental Methodology for Determining Optimum Process Parameters for Production of Hydrous Metal Oxides by Internal Gelation

    Energy Technology Data Exchange (ETDEWEB)

    Collins, J.L.

    2005-10-28

    The objective of this report is to describe a simple but very useful experimental methodology that was used to determine optimum process parameters for preparing several hydrous metal-oxide gel spheres by the internal gelation process. The method is inexpensive and very effective in collection of key gel-forming data that are needed to prepare the hydrous metal-oxide microspheres of the best quality for a number of elements.

  15. Monte Carlo calculations and experimental measurements of dosimetric parameters of the IRA-103Pd source

    International Nuclear Information System (INIS)

    Sadeghi, Mahdi; Hosseini, Hamed; Raisali, Gholamreza

    2008-01-01

    Full text: The use of 103 Pd seed sources for permanent prostate implantation has become a popular brachytherapy application. As recommended by AAPM the dosimetric characteristics of the new source must be determined using experimental and Monte Carlo simulations, before its use in clinical applications thus The goal of this report is the experimental and theoretical determination of the dosimetric characteristics of this source following the recommendations in the AAPM TG-43U1 protocol. Figure 1 shows the geometry of the IRA- 103 Pd source. The source consists of a cylindrical silver core, 0.3 cm long x 0.05 cm in diameter, onto which 0.5 nm layer of 103 Pd has been uniformly adsorbed. The effective active length of source is 0.3 cm and the silver core encapsulated inside a hollow titanium tube with 0.45 cm long, 0.07 cm and 0.08 inner and outer diameters and two caps. The Monte Carlo N-Particle (MCNP) code, version 4C, was used to determine the relevant dosimetric parameters of the source. The geometry of the Monte Carlo simulation performed in this study consisted of a sphere with 30 cm diameter. Dose distributions around this source were measured in two Perspex phantom using enough TLD chips. For these measurements, slabs of Perspex material were machined to accommodate the source and TLD chips. A value of 0.67± 1% cGy.h -1 .U -1 for, Λ, was calculated as the ratio of d(r 0 ,θ 0 ) and s K , that may be compared with Λ values obtained for 103 Pd sources. Result of calculations and measurements values of dosimetric parameters of the source including radial dose function, g(r), and anisotropy function, F(r,θ), has been shown in separate figures. The radial dose function, g(r), for the IRA- 103 Pd source and other 103 Pd sources is included in Fig. 2. Comparison between measured and Monte Carlo simulated dose function, g(r), and anisotropy function, F(r,θ), of this source demonstrated that they are in good agreement with each other and The value of Λ is

  16. EXPERIMENTAL STUDY OF MAGNETIC FLUID SEAL

    Directory of Open Access Journals (Sweden)

    V. G. Bashtovoi

    2006-01-01

    Full Text Available Dependences of critical pressure drop, being held by magnetic fluid seal, on time in a static state and shaft rotation velocity in dynamics have been experimentally determined. The significant influence of particles’ redistribution in magnetic fluid on static parameters of magnetic fluid seal has been established.

  17. Experimental determination and verification of the parameters used in a proton pencil beam algorithm

    International Nuclear Information System (INIS)

    Szymanowski, H.; Mazal, A.; Nauraye, C.; Biensan, S.; Ferrand, R.; Murillo, M.C.; Caneva, S.; Gaboriaud, G.; Rosenwald, J.C.

    2001-01-01

    We present an experimental procedure for the determination and the verification under practical conditions of physical and computational parameters used in our proton pencil beam algorithm. The calculation of the dose delivered by a single pencil beam relies on a measured spread-out Bragg peak, and the description of its radial spread at depth features simple specific parameters accounting individually for the influence of the beam line as a whole, the beam energy modulation, the compensator, and the patient medium. For determining the experimental values of the physical parameters related to proton scattering, we utilized a simple relation between Gaussian radial spreads and the width of lateral penumbras. The contribution from the beam line has been extracted from lateral penumbra measurements in air: a linear variation with the distance collimator-point has been observed. Analytically predicted radial spreads within the patient were in good agreement with experimental values in water under various reference conditions. Results indicated no significant influence of the beam energy modulation. Using measurements in presence of Plexiglas slabs, a simple assumption on the effective source of scattering due to the compensator has been stated, leading to accurate radial spread calculations. Dose measurements in presence of complexly shaped compensators have been used to assess the performances of the algorithm supplied with the adequate physical parameters. One of these compensators has also been used, together with a reference configuration, for investigating a set of computational parameters decreasing the calculation time while maintaining a high level of accuracy. Faster dose computations have been performed for algorithm evaluation in the presence of geometrical and patient compensators, and have shown good agreement with the measured dose distributions

  18. Experimental determination of chosen document elements parameters from raster graphics sources

    Directory of Open Access Journals (Sweden)

    Jiří Rybička

    2010-01-01

    Full Text Available Visual appearance of documents and their formal quality is considered to be as important as the content quality. Formal and typographical quality of documents can be evaluated by an automated system that processes raster images of documents. A document is described by a formal model that treats a page as an object and also as a set of elements, whereas page elements include text and graphic object. All elements are described by their parameters depending on elements’ type. For future evaluation, mainly text objects are important. This paper describes the experimental determination of chosen document elements parameters from raster images. Techniques for image processing are used, where an image is represented as a matrix of dots and parameter values are extracted. Algorithms for parameter extraction from raster images were designed and were aimed mainly at typographical parameters like indentation, alignment, font size or spacing. Algorithms were tested on a set of 100 images of paragraphs or pages and provide very good results. Extracted parameters can be directly used for typographical quality evaluation.

  19. Inference of missing data and chemical model parameters using experimental statistics

    Science.gov (United States)

    Casey, Tiernan; Najm, Habib

    2017-11-01

    A method for determining the joint parameter density of Arrhenius rate expressions through the inference of missing experimental data is presented. This approach proposes noisy hypothetical data sets from target experiments and accepts those which agree with the reported statistics, in the form of nominal parameter values and their associated uncertainties. The data exploration procedure is formalized using Bayesian inference, employing maximum entropy and approximate Bayesian computation methods to arrive at a joint density on data and parameters. The method is demonstrated in the context of reactions in the H2-O2 system for predictive modeling of combustion systems of interest. Work supported by the US DOE BES CSGB. Sandia National Labs is a multimission lab managed and operated by Nat. Technology and Eng'g Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell Intl, for the US DOE NCSA under contract DE-NA-0003525.

  20. Experimental studies on cancer chemotherapy

    International Nuclear Information System (INIS)

    1976-08-01

    The further development of the chemotherapy of cancer in the experimental and clinical fields necessitates a profound knowledge of its chemical, biochemical and pharmacological fundamentals and the mechanism of physiological and pathological growth processes. The 'Arbeitsgemeinschaft Zytostatika' includes chemists, biochemists, pharmacologists, molecular biologists, physicians and immunologists of various scientific institutes and clinics in the Federal Republic of Germany and in West Berlin. It is their aim to carry out basic research as well as clinical-orientated research in the field of the chemotherapy of cancer. In the 15 years of cooperation, fundamental knowledge was gained, especially in the field of the cytotoxic specificity and cancerotoxic selectivity of alkylating cytostatics. New cytostatics with a greater oncostatic selectivity and an altered spectrum of activity were tested and greater knowledge was won on the molecular-biological prerequisites of a rational drug design. (orig.) [de

  1. Study on parameter identification and control of ground temperature

    International Nuclear Information System (INIS)

    Kojima, Keiichi; Suzuki, Seiichi; Kawahara, Mutsuto.

    1995-01-01

    A numerical thermal management system for ground structure is presented. The system consists of two parts, i.e. the identification analysis of the thermal conductivity and the thermal control analysis for the ground. The former is carried out by using the nonlinear least squares method and the latter is based on the optimal control theory. The formulations of these methods are presented and they are applied to an laboratory test. A reasonable thermal conductivity of the ground is identified by parameter estimation method and the ground temperature is actually controled as illustrated by numerical and experimental study. (author)

  2. Experimental and Numerical Investigation of Design Parameters for Hydronic Embedded Thermally Active Surfaces

    DEFF Research Database (Denmark)

    Marcos-Meson, Victor; Pomianowski, Michal Zbigniew; E. Poulsen, Søren

    2015-01-01

    This paper evaluates the principal design parameters affecting the thermal performance of embedded hydronic Thermally Active Surfaces (TAS), combining the Response Surface Method (RSM) with the Finite Elements Method (FEM). The study ranks the combined effects of the parameters on the heat flux i...

  3. Comparison of different morphological parameters with duration of obstruction created experimentally in unilateral upper ureters: an animal model.

    Science.gov (United States)

    Panda, Shasanka Shekhar; Bajpai, Minu; Mallick, Saumyaranjan; Sharma, Mehar C

    2014-01-01

    The objective of the following study is to determine and to compare the different morphological parameters with duration of obstruction created experimentally in unilateral upper ureters of rats. Unilateral upper ureteric obstruction was created in 60 adult Wistar rats that were reversed after predetermined intervals. Rats were sacrificed and ipsilateral kidneys were subjected for analysis of morphological parameters such as renal height, cranio-caudal diameter, antero-posterior diameter, lateral diameter, volume of the pelvis and average cortical thickness: Renal height. Renal height and cranio-caudal diameter of renal pelvis after ipsilateral upper ureteric obstruction started rising as early as 7 days of creating obstruction and were affected earlier than antero-posterior and lateral diameter and also were reversed earlier than other parameters after reversal of obstruction. Renal cortical thickness and volume of the pelvis were affected after prolonged obstruction (> 3 weeks) and were the late parameters to be reversed after reversal of obstruction. Cranio-caudal diameter and renal height were the early morphological parameters to be affected and reversed after reversal of obstruction in experimentally created ipsilateral upper ureteric obstruction.

  4. Comparison of different morphological parameters with duration of obstruction created experimentally in unilateral upper ureters: An animal model

    Directory of Open Access Journals (Sweden)

    Shasanka Shekhar Panda

    2014-01-01

    Full Text Available Background: The objective of the following study is to determine and to compare the different morphological parameters with duration of obstruction created experimentally in unilateral upper ureters of rats. Materials and Methods: Unilateral upper ureteric obstruction was created in 60 adult Wistar rats that were reversed after predetermined intervals. Rats were sacrificed and ipsilateral kidneys were subjected for analysis of morphological parameters such as renal height, cranio-caudal diameter, antero-posterior diameter, lateral diameter, volume of the pelvis and average cortical thickness: Renal height. Results: Renal height and cranio-caudal diameter of renal pelvis after ipsilateral upper ureteric obstruction started rising as early as 7 days of creating obstruction and were affected earlier than antero-posterior and lateral diameter and also were reversed earlier than other parameters after reversal of obstruction. Renal cortical thickness and volume of the pelvis were affected after prolonged obstruction (> 3 weeks and were the late parameters to be reversed after reversal of obstruction. Conclusions: Cranio-caudal diameter and renal height were the early morphological parameters to be affected and reversed after reversal of obstruction in experimentally created ipsilateral upper ureteric obstruction.

  5. Model of twelve properties of a set of organic solvents with graph-theoretical and/or experimental parameters.

    Science.gov (United States)

    Pogliani, Lionello

    2010-01-30

    Twelve properties of a highly heterogeneous class of organic solvents have been modeled with a graph-theoretical molecular connectivity modified (MC) method, which allows to encode the core electrons and the hydrogen atoms. The graph-theoretical method uses the concepts of simple, general, and complete graphs, where these last types of graphs are used to encode the core electrons. The hydrogen atoms have been encoded by the aid of a graph-theoretical perturbation parameter, which contributes to the definition of the valence delta, delta(v), a key parameter in molecular connectivity studies. The model of the twelve properties done with a stepwise search algorithm is always satisfactory, and it allows to check the influence of the hydrogen content of the solvent molecules on the choice of the type of descriptor. A similar argument holds for the influence of the halogen atoms on the type of core electron representation. In some cases the molar mass, and in a minor way, special "ad hoc" parameters have been used to improve the model. A very good model of the surface tension could be obtained by the aid of five experimental parameters. A mixed model method based on experimental parameters plus molecular connectivity indices achieved, instead, to consistently improve the model quality of five properties. To underline is the importance of the boiling point temperatures as descriptors in these last two model methodologies. Copyright 2009 Wiley Periodicals, Inc.

  6. Experimental and computational correlation of fracture parameters KIc, JIc, and GIc for unimodular and bimodular graphite components

    Science.gov (United States)

    Bhushan, Awani; Panda, S. K.

    2018-05-01

    The influence of bimodularity (different stress ∼ strain behaviour in tension and compression) on fracture behaviour of graphite specimens has been studied with fracture toughness (KIc), critical J-integral (JIc) and critical strain energy release rate (GIc) as the characterizing parameter. Bimodularity index (ratio of tensile Young's modulus to compression Young's modulus) of graphite specimens has been obtained from the normalized test data of tensile and compression experimentation. Single edge notch bend (SENB) testing of pre-cracked specimens from the same lot have been carried out as per ASTM standard D7779-11 to determine the peak load and critical fracture parameters KIc, GIc and JIc using digital image correlation technology of crack opening displacements. Weibull weakest link theory has been used to evaluate the mean peak load, Weibull modulus and goodness of fit employing two parameter least square method (LIN2), biased (MLE2-B) and unbiased (MLE2-U) maximum likelihood estimator. The stress dependent elasticity problem of three-dimensional crack progression behaviour for the bimodular graphite components has been solved as an iterative finite element procedure. The crack characterizing parameters critical stress intensity factor and critical strain energy release rate have been estimated with the help of Weibull distribution plot between peak loads versus cumulative probability of failure. Experimental and Computational fracture parameters have been compared qualitatively to describe the significance of bimodularity. The bimodular influence on fracture behaviour of SENB graphite has been reflected on the experimental evaluation of GIc values only, which has been found to be different from the calculated JIc values. Numerical evaluation of bimodular 3D J-integral value is found to be close to the GIc value whereas the unimodular 3D J-value is nearer to the JIc value. The significant difference between the unimodular JIc and bimodular GIc indicates that

  7. Study of photodissociation parameters of carboxyhemoglobin

    International Nuclear Information System (INIS)

    Kuz'min, V V; Salmin, V V; Provorov, A S; Salmina, A B

    2008-01-01

    The general properties of photodissociation of carboxyhemoglobin (HbCO) in buffer solutions of whole human blood are studied by the flash photolysis method on a setup with intersecting beams. It is shown that the efficiency of photoinduced dissociation of the HbCO complex virtually linearly depends on the photolytic irradiation intensity for the average power density not exceeding 45 mW cm -2 . The general dissociation of the HbCO complex in native conditions occurs in a narrower range of values of the saturation degree than in model experiments with the hemoglobin solution. The dependence of the pulse photolysis efficiency of HbCO on the photolytic radiation wavelength in the range from 550 to 585 nm has a broad bell shape. The efficiency maximum corresponds to the electronic Q transition (porphyrin π-π* absorption) in HbCO at a wavelength of 570 nm. No dissociation of the complex was observed under given experimental conditions upon irradiation of solutions by photolytic radiation at wavelengths above 585 nm. (laser applications and other topics in quantum electronics)

  8. Assessment of reduced-order unscented Kalman filter for parameter identification in 1-dimensional blood flow models using experimental data.

    Science.gov (United States)

    Caiazzo, A; Caforio, Federica; Montecinos, Gino; Muller, Lucas O; Blanco, Pablo J; Toro, Eluterio F

    2016-10-25

    This work presents a detailed investigation of a parameter estimation approach on the basis of the reduced-order unscented Kalman filter (ROUKF) in the context of 1-dimensional blood flow models. In particular, the main aims of this study are (1) to investigate the effects of using real measurements versus synthetic data for the estimation procedure (i.e., numerical results of the same in silico model, perturbed with noise) and (2) to identify potential difficulties and limitations of the approach in clinically realistic applications to assess the applicability of the filter to such setups. For these purposes, the present numerical study is based on a recently published in vitro model of the arterial network, for which experimental flow and pressure measurements are available at few selected locations. To mimic clinically relevant situations, we focus on the estimation of terminal resistances and arterial wall parameters related to vessel mechanics (Young's modulus and wall thickness) using few experimental observations (at most a single pressure or flow measurement per vessel). In all cases, we first perform a theoretical identifiability analysis on the basis of the generalized sensitivity function, comparing then the results owith the ROUKF, using either synthetic or experimental data, to results obtained using reference parameters and to available measurements. Copyright © 2016 John Wiley & Sons, Ltd.

  9. Hot forming of composite prepreg : Experimental study

    Science.gov (United States)

    Tardif, Xavier; Duthille, Bertrand; Bechtel, Stephane; le Pinru, Louis; Campagne, Benjamin; Destombes, Gautier; Deshors, Antoine; Marchand, Christophe; Azzouzi, Khalid El; Moro, Tanguy

    2017-10-01

    The hot forming of thermoset prepreg consists in bending an uncured composite part by applying a mechanical constrain on the hot laminate. Most of the time, the mold is inserted in a vacuum box and the mechanical constrain is applied on the composite laminate by a single membrane or a double-membrane. But the performance improvement products resulted in forming increasingly complex parts with advanced materials having a less formability. These new complex parts require a finer comprehension of the process and an optimization of the key parameters to get acceptable quality. In this work, an experimental study has been carried out to identify the process conditions that do not lead to unacceptable defaults: undulations of fibers. In the present study, downward-bending has been evaluated with an original light mechanical forming concept, for a given stacking sequence. The influence of the part's temperature and the part's bending speed are investigated. To carry this study out, a hot forming test bench has been designed and manufactured to have a precise supervision of the process conditions. It is able to bend parts of 1500 mm length x 600 mm width x 20 mm thick.

  10. Correlating neutron yield and reliability for selecting experimental parameters for a plasma focus machine

    International Nuclear Information System (INIS)

    Pross, G.

    Possibilities of optimizing focus machines with a given energy content in the sense of high neutron yield and high reliability of the discharges are investigated experimentally. For this purpose, a focus machine of the Mather type with an energy content of 12 kJ was constructed. The following experimental parameters were varied: the material of the insulator in the ignition zone, the structure of the outside electrode, the length of the inside electrode, the filling pressure and the amount and polarity of the battery voltage. An important part of the diagnostic program consists of measurements of the azimuthal and axial current distribution in the accelerator, correlated with short-term photographs of the luminous front as a function of time. The results are given. A functional schematic has been drafted for focus discharge as an aid in extensive optimization of focus machines, combining findings from theory and experiments. The schematic takes into account the multiparameter character of the discharge and clarifies relationships between the experimental parameters and the target variables neutron yield and reliability

  11. Evaluation of Experimental Parameters in the Accelerated Aging of Closed-Cell Foam Insulation

    Energy Technology Data Exchange (ETDEWEB)

    Stovall, Therese K [ORNL; Vanderlan, Michael [ORNL; Atchley, Jerald Allen [ORNL

    2012-12-01

    The thermal conductivity of many closed-cell foam insulation products changes over time as production gases diffuse out of the cell matrix and atmospheric gases diffuse into the cells. Thin slicing has been shown to be an effective means of accelerating this process in such a way as to produce meaningful results. Efforts to produce a more prescriptive version of the ASTM C1303 standard test method led to the ruggedness test described here. This test program included the aging of full size insulation specimens for time periods of five years for direct comparison to the predicted results. Experimental parameters under investigation include: slice thickness, slice origin (at the surface or from the core of the slab), thin slice stack composition, product facings, original product thickness, product density, and product type. The test protocol has been completed and this report provides a detailed evaluation of the impact of the test parameters on the accuracy of the 5-year thermal conductivity prediction.

  12. Experimental determination of solubility parameters of oils as a function of pressure

    DEFF Research Database (Denmark)

    Verdier, Sylvain Charles Roland; Duong, Diep; Andersen, Simon Ivar

    2005-01-01

    In this work, the solubility parameter of dead and live crude oils was measured at 303.15 K and up to 300 bar, using the internal pressure approach. An indirect technique was chosen, using thermal expansivities (determined from microcalorimetric measurements) and isothermal compressibilities (cal...... are measured and given as input. Therefore, a more appropriate characterization method should give better results....... (calculated from density measurements). This method was tested on seven pure compounds, and the deviation with literature data is method based on the refractive index was used to examine the validity of the results for the oils, and a deviation of ... parameter was also calculated from two cubic equations of state and compared to experimental results. In this case, the deviations are larger (up to 6.5 MPa1/2), whereas this approach gives accurate results for pure compounds. This might be due to the characterization procedure, because the volumes...

  13. On determination of microphone response and other parameters by a hybrid experimental and numerical method

    DEFF Research Database (Denmark)

    Barrera Figueroa, Salvador; Jacobsen, Finn; Rasmussen, Knud

    2008-01-01

    to this problem is to measure the velocity distribution of the membrane by means of a non-contact method, such as laser vibrometry. The measured velocity distributions can be used together with a numerical formulation such as the Boundary Element Method for estimating the microphone response and other parameters...... such as the acoustic centres. In this work, a hybrid method is presented. The velocity distributions of condenser Laboratory Standard microphones were measured using a laser vibrometer. This measured velocity distribution was used for estimating the microphone responses and parameters. The agreement with experimental......Typically, numerical calculations of the pressure, free-field and random-incidence response of a condenser microphone are carried out on the basis of an assumed displacement distribution of the diaphragm of the microphone; the conventional assumption is that the displacement follows a Bessel...

  14. Experimental Characterization of Ultra-Wideband Channel Parameter Measurements in an Underground Mine

    Directory of Open Access Journals (Sweden)

    B. Nkakanou

    2011-01-01

    Full Text Available Experimental results for an ultra-wideband (UWB channel parameters in an underground mining environment over a frequency range of 3 GHz to 10 GHz are reported. The measurements were taken both in LOS and NLOS cases in two different size mine galleries. In the NLOS case, results were acquired for different corridor obstruction angles. The results were obtained during an extensive measurement campaign in the UWB frequency, and the measurement procedure allows both the large- and small-scale parameters such as the path loss exponent, coherence bandwidth, and so forth, to be quantified. The capacity of the UWB channel as a function of the physical depth of the mine gallery has also been recorded for comparison purposes.

  15. 2000 CKM-triangle analysis a critical review with updated experimental inputs and theoretical parameters

    International Nuclear Information System (INIS)

    Roudeau, P.; Stocchi, A.; Ciuchini, M.; Lubicz, V.; D'Agostini, G.; Franco, E.; Martinelli, G.; Parodi, F.

    2000-12-01

    Within the Standard Model, a review of the current determination of the sides and angles of the CKM unitarity triangle is presented, using experimental constraints from the measurements of |ε K |, |V ub /V cb |, Δm d and from the limit on Δm s , available in September 2000. Results from the experimental search for B 0 s -B-bar 0 s oscillations are introduced in the present analysis using the likelihood. Special attention is devoted to the determination of the theoretical uncertainties. The purpose of the analysis is to infer regions where the parameters of interest lie with given probabilities. The BaBar '95% C.L. scanning' method is also commented. (authors)

  16. Experimental evaluation of local bubble parameters of subcooled boiling flow in a pressurized vertical annulus channel

    Energy Technology Data Exchange (ETDEWEB)

    Chu, In-Cheol, E-mail: chuic@kaeri.re.kr; Lee, Seung-Jun; Youn, Young Jung; Park, Jong Kuk; Choi, Hae Seob; Euh, Dong-Jin; Song, Chul-Hwa

    2017-02-15

    Experiments were performed to quantify the local bubble parameters such as void fraction, bubble velocity, interfacial area concentration, and Sauter mean diameter for the subcooled boiling flow of a refrigerant R-134a in a pressurized vertical annulus channel. Optical fiber void probe and double pressure boundary visualization windows were installed at four measurement stations with different elevations, thus enabling the quantification of local bubble parameters and observation of global boiling structure. Using high-resolution traverse systems for the optical fiber void probes and the heating tube, the radial profiles of the bubble parameters and their axial propagation can be evaluated at any elevation of the whole heating region. At this first phase of the experiments, three tests were conducted by varying the pressure, heat flux, mass flux, and local liquid subcooling. The radial profiles of the bubble parameters were obtained at seven elevations. The pressure condition of the present experiments covered the normal operating pressure of PWRs according to the similarity criteria. The present experimental data will be useful for thorough validation and improvement of the CMFD (Computation Multi-Fluid Dynamics) codes and constitutive relations.

  17. Experimental parameters for quantitative surface analysis by medium energy ion scattering, ch. 1

    International Nuclear Information System (INIS)

    Turkenburg, W.C.; Kersten, H.H.; Colenbrander, B.G.; Jongh, A.P. de; Saris, F.W.

    1976-01-01

    A new UHV chamber for surface and surface layer analysis by collision spectroscopy of backscattered ions at medium energies is described. Experimental parameters like energy, angular and depth resolution, crystal alignment and background pressure are discussed. Formulae based on the use of an electrostatic energy analyser show that the analysis can be quantitative. Effects of beam induced build-up of a hydro-carbon layer, sputter cleaning and creation of radiation damage have been investigated for Cu (110) and Ni (110). Detection sensitivity for Carbon, Oxygen and Sulfur on Cu and Ni has been found to be 0.2, 0.1 and 0.03 of a monolayer respectively

  18. Experimental study of the longitudinal instability for beam transport

    International Nuclear Information System (INIS)

    Reiser, M.; Wang, J.G.; Guo, W.M.; Wang, D.X.

    1990-01-01

    Theoretical model for beam longitudinal instability in a transport pipe with general wall impedance is considered. The result shows that a capacitive wall tends to stabilize the beam. The experimental study of the instability for a pure resistive-wall is presented, including the design parameters, setup and components for the experiment. 6 refs., 3 figs

  19. Experimental studies of neutrino oscillations

    CERN Document Server

    Kajita, Takaaki

    2016-01-01

    The 2015 Nobel Prize in physics has been awarded to Takaaki Kajita and Arthur McDonald "for the discovery of neutrino oscillations, which shows that neutrinos have mass". Takaaki Kajita of Tokyo University is a Japanese physicist, known for neutrino experiments at the Kamiokande and its successor, Super-Kamiokande. This volume of collected works of Kajita on neutrino oscillations provides a good glimpse into as well as a record of the rise and the role of Asian research in the frontiers of neutrino physics. Japan is now a major force in the study of the 3 families of neutrinos. Much remains to be done to clarify the Dirac vs. Majorana nature of the neutrino, and the cosmological implications of the neutrino. The collected works of Kajita and his Super-Kamiokande group will leave an indelible foot-print in the history of big and better science.

  20. Fuel cycle parameters for strategy studies

    International Nuclear Information System (INIS)

    Archinoff, G.H.

    1979-05-01

    This report summarizes seven fuel cycle parameters (efficiency, specific power, burnup, equilibrium net fissile feed, equilibrium net fissile surplus, first charge fissile content, and whether or not fuel reprocessing is required) to be used in long-term strategy analyses of fuel cycles based on natural UO 2 , low enriched uranium, mixed oxides, plutonium topped thorium, uranium topped thorium, and the fast breeder oxide cycle. (LL)

  1. The study of superconducting order parameter dynamics

    International Nuclear Information System (INIS)

    Goldman, A.M.

    1988-01-01

    Flux quantization experiments have demonstrated the importance of long range phase coherence in the description of the superconducting state, an idea originally proposed as an integral part of the phenomenological theory of the Meissner-Ochsenfeld effect. The most striking experimental demonstration of the phase coherence of the superconducting state is that the maximum dc Josephson current in a thin-film tunneling junction exhibits a Fraunhofer-like dependence on magnetic field

  2. Evaluation of the low-level laser therapy application parameters for skin burn treatment in experimental model: a systematic review.

    Science.gov (United States)

    Brassolatti, Patricia; de Andrade, Ana Laura Martins; Bossini, Paulo Sérgio; Otterço, Albaiza Nicoletti; Parizotto, Nivaldo Antônio

    2018-05-05

    Burn is defined as a traumatic injury of thermal origin, which affects the organic tissue. Low-level laser therapy (LLLT) has gained great prominence as a treatment in this type of injury; however, the application parameters are still controversial in the literature. The aims of this study were to review the literature studies that use LLLT as a treatment in burns conducted in an experimental model, discuss the main parameters used, and highlight the benefits found in order to choose an appropriate therapeutic window to be applied in this type of injury. The selection of the studies related to the theme was carried out in the main databases (PubMed, Cochrane Library, LILACS, Web of Science, and Scopus in the period from 2001 to 2017). Subsequently, the articles were then chosen that fell within the inclusion criteria previously established. In the end, 22 were evaluated, and the main parameters were presented. The analyzed studies presented both LLLT use in continuous and pulsed mode. Differences between the parameters used (power, fluence, and total energy) were observed. In addition, the protocols are distinct as to the type of injury and the number of treatment sessions. Among the results obtained by the authors are the improvements in the local microcirculation and cellular proliferation; however, a study reported no effects with LLLT as a treatment. LLLT is effective in accelerating the healing process. However, there is immense difficulty in establishing the most adequate protocol, due to the great discrepancy found in the applied dosimetry values.

  3. Combined Teaching Method: An Experimental Study

    Science.gov (United States)

    Kolesnikova, Iryna V.

    2016-01-01

    The search for the best approach to business education has led educators and researchers to seek many different teaching strategies, ranging from the traditional teaching methods to various experimental approaches such as active learning techniques. The aim of this experimental study was to compare the effects of the traditional and combined…

  4. Experimental studies of the quantum chromodynamics phase ...

    Indian Academy of Sciences (India)

    2015-05-06

    BES) ... Experimental studies of the QCD phase diagram at the STAR experiment .... However, the observed difference between v2 of particles and antiparticles could .... The grey band at the right corresponds to systematic.

  5. Experimental study on transient boiling heat transfer

    International Nuclear Information System (INIS)

    Visentini, R.

    2012-01-01

    well. A flexible power supply that can generate a free-shape signal, allows to get to a wall-temperature increase rate up to 2500 K/s but also to obtain lower rates, which permits to study weaker transients and steady state conditions. The thermal measurements are realised by means of an infra-red camera and a high-speed camera is employed in order to see the boiling phenomena at the same time. From the voltage and current measurements the heat flux that is passed to the fluid is known. It is possible to underline some of the main results of this work. We found that, even when the boiling onset occurs soon because of the high power, transient conduction is always coupled with transient convection. The boiling onset occurs when the wall superheat is between 10 K et 30 K. This value corresponds to the activation of the smallest nucleation sites at the wall. The literature correlations well fit the nucleate boiling data in steady-state conditions. When the wall-temperature increase rate leads to transient boiling, the heat flux is higher than in steady state. This is consistent with what was found in previous studies. The nucleate boiling phase may last only a few milliseconds when the power is really high and the wall temperature increases really rapidly (500-2000 K/s). The experiments in transient boiling also point out that the heat flux is larger than in steady state conditions for the other regimes: Critical heat flux and also film boiling. The experimental set-up allows to investigate a large range of parameters (wall-temperature increase rate, flow rate, fluid temperature) by means of accurate temperature measurements and visualisations. Some modeling of the heat transfer are also proposed. (author)

  6. Experimental parameters optimization of instrumental neutron activation analysis in order to determine selected elements in some industrial soils in Turkey

    International Nuclear Information System (INIS)

    Haciyakupoglu, Sevilay; Nur Esen, Ayse; Erenturk, Sema

    2014-01-01

    The purpose of this study is optimization of the experimental parameters for analysis of soil matrix by instrumental neutron activation analysis and quantitative determination of barium, cerium, lanthanum, rubidium, scandium and thorium in soil samples collected from industrialized urban areas near Istanbul. Samples were irradiated in TRIGA MARK II Research Reactor of Istanbul Technical University. Two types of reference materials were used to check the accuracy of the applied method. The achieved results were found to be in compliance with certified values of the reference materials. The calculated E n numbers for mentioned elements were found to be less than 1. The presented data of element concentrations in soil samples will help to trace the pollution as an impact of urbanization and industrialization, as well as providing database for future studies. - Highlights: • Optimization of experimental parameters is important for high sensitivity results by INAA. • Assessment of uncertainty sources is necessary to increase reliability of results. • The aim of this study is to determine a number of elements in industrial soil samples. • The higher concentrations of studied elements are due to rapid industrialization. • This baseline data can be used in future studies for other industrial areas

  7. Evaluation of the effect of conventionally prepared swarna makshika bhasma on different bio-chemical parameters in experimental animals

    Directory of Open Access Journals (Sweden)

    Sudhaldev Mohapatra

    2011-01-01

    Full Text Available Swarna makshika (chalcopyrite bhasma (SMB has been used for different therapeutic purposes since long in Ayurveda. The present study is conducted to evaluate the effect of conventionally prepared SMB on different bio-chemical parameters in experimental animals, for providing scientific data base for its logical use in clinical practice. The genuine SMB was prepared by following classical techniques of shodhana and marana most commonly used by different Ayurvedic drug manufacturers. Shodhana was done by roasting raw swarna makshika with lemon juice for three days and marana was performed by 11 putas . The experimental animals (rats were divided into two groups. SMB mixed with diluted honey was administered orally in therapeutic dose to Group SMB and diluted honey only was administered to vehicle control Group, for 30 days. The blood samples were collected twice, after 15 days and after 30 days of drug administration and different biochemical investigations were done. Biochemical parameters were chosen based on references from Ayurvedic classics and contemporary medicine. It was observed that Hb% was found significantly increased and LDL and VLDL were found significantly decreased in Group SMB when compared with vehicle control group. This experimental data will help the clinician for the logical use of SMB in different disease conditions with findings like low Hb% and high LDL, VLDL levels.

  8. Experimental study and modeling of a novel magnetorheological elastomer isolator

    International Nuclear Information System (INIS)

    Yang, Jian; Li, Weihua; Sun, Shuaishuai; Du, Haiping; Li, Yancheng; Li, Jianchun; Deng, H X

    2013-01-01

    This paper reports an experimental setup aiming at evaluating the performance of a newly designed magnetorheological elastomer (MRE) seismic isolator. As a further effort to explore the field-dependent stiffness/damping properties of the MRE isolator, a series of experimental testing were conducted. Based upon the analysis of the experimental responses and the characteristics of the MRE isolator, a new model that is capable of reproducing the unique MRE isolator dynamics behaviors is proposed. The validation results verify the model’s effectiveness to portray the MRE isolator. A study on the field-dependent parameters is then provided to make the model valid with fluctuating magnetic fields. To fully explore the mechanism of the proposed model, an investigation relating the dependence of the proposed model on every parameter is carried out. (technical note)

  9. Bridges Dynamic Parameters Identification Based On Experimental and Numerical Method Comparison in Regard with Traffic Seismicity

    Science.gov (United States)

    Krkošková, Katarína; Papán, Daniel; Papánová, Zuzana

    2017-10-01

    The technical seismicity negatively affects the environment, buildings and structures. Technical seismicity means seismic shakes caused by force impulse, random process and unnatural origin. The vibration influence on buildings is evaluated in the Eurocode 8 in Slovak Republic, however, the Slovak Technical Standard STN 73 0036 includes solution of the technical seismicity. This standard also classes bridges into the group of structures that are significant in light of the technical seismicity - the group “U”. Using the case studies analysis by FEM simulation and comparison is necessary because of brief norm evaluation of this issue. In this article, determinate dynamic parameters by experimental measuring and numerical method on two real bridges are compared. First bridge, (D201 - 00) is Scaffold Bridge on the road I/11 leading to the city of Čadca and is situated in the city of Žilina. It is eleven - span concrete road bridge. The railway is the obstacle, which this bridge spans. Second bridge (M5973 Brodno) is situated in the part of Žilina City on the road of I/11. It is concrete three - span road bridge built as box girder. The computing part includes 3D computational models of the bridges. First bridge (D201 - 00) was modelled in the software of IDA Nexis as the slab - wall model. The model outputs are natural frequencies and natural vibration modes. Second bridge (M5973 Brodno) was modelled in the software of VisualFEA. The technical seismicity corresponds with the force impulse, which was put into this model. The model outputs are vibration displacements, velocities and accelerations. The aim of the experiments was measuring of the vibration acceleration time record of bridges, and there was need to systematic placement of accelerometers. The vibration acceleration time record is important during the under - bridge train crossing, about the first bridge (D201 - 00) and the vibration acceleration time domain is important during deducing the force

  10. Experimental investigation of a draft tube spouted bed for effects of geometric parameters on operation

    DEFF Research Database (Denmark)

    Azizaddini, Seyednezamaddin; Lin, Weigang; Dam-Johansen, Kim

    2016-01-01

    Experiments are performed in a draft tube spouted bed (DTSB) to investigate effects of the operating conditions and the geometric parameters on the hydrodynamics. Geometry parameters, such as heights of the entrained zone, draft tube inner diameter, inner angle of the conical section were studied....... Increasing the draft tube inner diameter, sharper inner angle of the conical section and higher height of entrained zone increase the internal solid circulation rate and the pressure drop. Even though, for all different configurations, higher gas feeding rate leads to higher internal solid circulation rate...

  11. Experimental Studies of the Effects of Anode Composition and Process Parameters on Anode Slime Adhesion and Cathode Copper Purity by Performing Copper Electrorefining in a Pilot-Scale Cell

    Science.gov (United States)

    Zeng, Weizhi; Wang, Shijie; Free, Michael L.

    2016-10-01

    Copper electrorefining tests were conducted in a pilot-scale cell under commercial tankhouse environment to study the effects of anode compositions, current density, cathode blank width, and flow rate on anode slime behavior and cathode copper purity. Three different types of anodes (high, mid, and low impurity levels) were used in the tests and were analyzed under SEM/EDS. The harvested copper cathodes were weighed and analyzed for impurities concentrations using DC Arc. The adhered slimes and released slimes were collected, weighed, and analyzed for compositions using ICP. It was shown that the lead-to-arsenic ratio in the anodes affects the sintering and coalescence of slime particles. High current density condition can improve anode slime adhesion and cathode purity by intensifying slime particles' coalescence and dissolving part of the particles. Wide cathode blanks can raise the anodic current densities significantly and result in massive release of large slime particle aggregates, which are not likely to contaminate the cathode copper. Low flow rate can cause anode passivation and increase local temperatures in front of the anode, which leads to very intense sintering and coalescence of slime particles. The results and analyses of the tests present potential solutions for industrial copper electrorefining process.

  12. The impact of confinement scaling on ITER [International Thermonuclear Experimental Reactor] parameters

    International Nuclear Information System (INIS)

    Reid, R.L.; Galambos, J.D.; Peng, Y.K.M.

    1988-09-01

    Energy confinement scaling is a major concern in the design of the International Thermonuclear Experimental Reactor (ITER). The existing database for tokamaks can be fitted with a number of different confinement scaling expressions that have similar degrees of approximation. These scaling laws predict confinement times for ITER that vary by over an order of magnitude. The uncertainties in the form and magnitude of these scaling laws must be substantially reduced before the plasma performance of ITER can be predicted with adequate reliability. The TETRA systems code is used to calculate the dependence of major ITER parameters on the scaling laws currently in use. Design constraints of interest in the present phase of ITER consideration are used, and the minimum-cost devices arising from these constraints are reviewed. 9 refs., 13 figs., 4 tabs

  13. Experimental determination of the x-ray atomic fundamental parameters of nickel

    Science.gov (United States)

    Ménesguen, Y.; Lépy, M.-C.; Hönicke, P.; Müller, M.; Unterumsberger, R.; Beckhoff, B.; Hoszowska, J.; Dousse, J.-Cl; Błachucki, W.; Ito, Y.; Yamashita, M.; Fukushima, S.

    2018-02-01

    The x-ray atomic properties of nickel (Ni) were investigated in a unique approach combining different experimental techniques to obtain new, useful and reliable values of atomic fundamental parameters for x-ray spectrometric purposes and for comparison with theoretical predictions. We determined the mass attenuation coefficients in an energy range covering the L- and K-absorption edges, the K-shell fluorescence yield and the Kβ/Kα and Kβ1, 3/Kα1, 2 transition probability ratios. The obtained line profiles and linewidths of the Kα and Kβ transitions in Ni can be considered as the contribution of the satellite lines arising from the [KM] shake processes suggested by Deutsch et al (1995 Phys. Rev. A 51 283) and Ito et al (2016 Phys. Rev. A 94 042506). Comparison of the new data with several databases showed good agreement, but also discrepancies were found with existing tabulated values.

  14. Experimental research on dispersion parameters of ground water around the area of CIAE

    International Nuclear Information System (INIS)

    Yu Jun

    1993-01-01

    The dispersion are important parameters in modeling the migration of pollutant in the ground water. Due to the complexity of geological media, variant dispersion is expected according to the difference of the geological media. Three parts are included in physical simulation in the laboratory column, tracer experiment in the field and the prediction of dispersion using the stochastic model. Experimental results show that the dispersion obtained in the column are three orders of magnitude smaller than that obtained in the field. Using the field values of conductivity and stochastic theory, the calculated asymptotic longitudinal and lateral dispersion are 370 and 0.45 meters respectively and the correlation length is 400 meters approximately. Using the dispersion obtained from the formula in the paper can enhance the precision of the model prediction, the distance heeded to reach the Fick's dispersion is 6 km approximately

  15. [Experimental rationale for the parameters of a rapid method for oxidase activity determination].

    Science.gov (United States)

    Butorina, N N

    2010-01-01

    Experimental rationale is provided for the parameters of a rapid (1-2-min) test to concurrently determine the oxidase activity of all bacteria grown on the membrane filter after water filtration. Oxidase reagents that are the aqueous solutions of tetramethyl-p-phenylenediamine dihydrochloride and demethyl-p-phenylenediamine dihydrochloride have been first ascertained to exert no effect on the viability and enzymatic activity of bacteria after one-hour contact. An algorithm has been improved for the rapid oxidase activity test: the allowable time for bacteria to contact oxidase reagents and procedures for minimizing the effect on bacterial biochemical activity following the contact. An accelerated method based on lactose medium with tergitol 7 and Endo agar has been devised to determine coliform bacteria, by applying the rapid oxidase test: the time of a final response is 18-24 hours. The method has been included into GOST 52426-2005.

  16. Experimental design optimisation: theory and application to estimation of receptor model parameters using dynamic positron emission tomography

    International Nuclear Information System (INIS)

    Delforge, J.; Syrota, A.; Mazoyer, B.M.

    1989-01-01

    General framework and various criteria for experimental design optimisation are presented. The methodology is applied to estimation of receptor-ligand reaction model parameters with dynamic positron emission tomography data. The possibility of improving parameter estimation using a new experimental design combining an injection of the β + -labelled ligand and an injection of the cold ligand is investigated. Numerical simulations predict remarkable improvement in the accuracy of parameter estimates with this new experimental design and particularly the possibility of separate estimations of the association constant (k +1 ) and of receptor density (B' max ) in a single experiment. Simulation predictions are validated using experimental PET data in which parameter uncertainties are reduced by factors ranging from 17 to 1000. (author)

  17. Calculating the parameters of experimental data Gauss distribution using the least square fit method and evaluation of their accuracy

    International Nuclear Information System (INIS)

    Guseva, E.V.; Peregudov, V.N.

    1982-01-01

    The FITGAV program for calculation of parameters of the Gauss curve describing experimental data is considered. The calculations are based on the least square fit method. The estimations of errors in the parameter determination as a function of experimental data sample volume and their statistical significance are obtained. The curve fit using 100 points occupies less than 1 s at the SM-4 type computer

  18. Hepatic encephalopathy: experimental studies on the pathogenesis

    NARCIS (Netherlands)

    R.J. de Knegt (Robert)

    1993-01-01

    textabstractAims of this thesis: 1. To study, in rabbits, the suitability of experimental acute liver failure and acute hyperammonemia simulating acute liver failure for the study of hepatic encephalopathy and ammonia toxicity. 2. To study glutamate neurotransmission in rabbits with acute liver

  19. Influence of a productive solution of uranium on some biochemical parameters of blood of an organism at experimental animals

    International Nuclear Information System (INIS)

    Svambaev, Z.A.; Svambaev, E.A.; Sultanbekov, G.A; Tusupbekova, S.T.

    2010-01-01

    In the work authors inform results on studying influence of a productive solution of uranium on some biochemical parameters of blood of an organism at experimental animals. It is established that all samples of a productive solution of uranium possesses high toxicity and causes destruction of experimental animals with infringement of a picture of blood. Experiments on influence on biochemical and hematology defined parameters of blood on chickens - broilers and on which female quails from daily age raised on cellular batteries in communities on 50 heads in conditions adequate to the requirement. Fed in plenty with the dry forages prepared according to 'Recommendations on the normalized feeding an agricultural bird' (1996), recipes 5-2; 6-1. To chickens in plenty allowed water from auto drinking bowls. Conditions of a micro climate corresponded to hygienic requirements. At carrying out of experiences studied the following parameters: preservation of a livestock, the reason of a withdrawal, weight of a body - weekly up to the end of experience, consumption of a forage, an expense of a forage for 1 kg of a gain have established weight of a body the methods standard in poultry farming. After application of a productive solution took blood from under wings of a vein and in blood have established maintenance of hemoglobin, quantity of red cells, leukocytes and a leukocyte of the formula, the maintenance of calcium and phosphorus. An application of a productive solution for experimental birds for the fifth day has caused clinical symptoms of a poisoning and destruction in groups. At the survived birds in blood it has been established changes biochemical and hematology. Week age chickens of skilled group lagged behind in growth development in comparison with control group on 30 % and at the end of the skilled period skilled have lagged behind in growth and development on 62 %. Among a livestock of chickens of skilled group of a case was more on 53 % on comparisons with the

  20. An experimental study on effect of process parameters in deep ...

    African Journals Online (AJOL)

    DR OKE

    Indeed, deep drawing is one of the widely used sheet metal forming process ... and quality of business process by the use of statistical tools (Chen and Lyu, 2009). ... Selection of control factors and their levels are made on the basis of some.

  1. Multi-parameter study of gammas capture

    International Nuclear Information System (INIS)

    Samama, R.; Nifenecker, H.; Carlos, P.; Delaitre, B.

    1966-06-01

    This equipment is intended for analyzing, recording, and reading simultaneous information from several 'gamma' detectors. It allows multiparameter study of γ-γ cascades emitted after thermal neutrons capture. (authors) [fr

  2. Parameter motivated mutual correlation analysis: Application to the study of currency exchange rates based on intermittency parameter and Hurst exponent

    Science.gov (United States)

    Cristescu, Constantin P.; Stan, Cristina; Scarlat, Eugen I.; Minea, Teofil; Cristescu, Cristina M.

    2012-04-01

    We present a novel method for the parameter oriented analysis of mutual correlation between independent time series or between equivalent structures such as ordered data sets. The proposed method is based on the sliding window technique, defines a new type of correlation measure and can be applied to time series from all domains of science and technology, experimental or simulated. A specific parameter that can characterize the time series is computed for each window and a cross correlation analysis is carried out on the set of values obtained for the time series under investigation. We apply this method to the study of some currency daily exchange rates from the point of view of the Hurst exponent and the intermittency parameter. Interesting correlation relationships are revealed and a tentative crisis prediction is presented.

  3. Experimental design of a waste glass study

    International Nuclear Information System (INIS)

    Piepel, G.F.; Redgate, P.E.; Hrma, P.

    1995-04-01

    A Composition Variation Study (CVS) is being performed to support a future high-level waste glass plant at Hanford. A total of 147 glasses, covering a broad region of compositions melting at approximately 1150 degrees C, were tested in five statistically designed experimental phases. This paper focuses on the goals, strategies, and techniques used in designing the five phases. The overall strategy was to investigate glass compositions on the boundary and interior of an experimental region defined by single- component, multiple-component, and property constraints. Statistical optimal experimental design techniques were used to cover various subregions of the experimental region in each phase. Empirical mixture models for glass properties (as functions of glass composition) from previous phases wee used in designing subsequent CVS phases

  4. Experimental radiation carcinogenesis is studies at NIRS

    International Nuclear Information System (INIS)

    Sado, Toshihiko

    1992-01-01

    Experimental radiation carcinogenesis studies conducted during the past decade at NIRS are briefly reviewed. They include the following: 1) Age dependency of susceptibility to radiation carcinogenesis. 2) Radiation-induced myeloid leukemia. 3) Mechanism of fractionated X-irradiation (FX) induced thymic lymphomas. 4) Significance of radiation-induced immunosuppression in radiation carcinogenesis in vivo. 5) Other ongoing studies. (author)

  5. The Numerical Calculation and Experimental Measurement of the Inductance Parameters for Permanent Magnet Synchronous Motor in Electric Vehicle

    Science.gov (United States)

    Jiang, Chao; Qiao, Mingzhong; Zhu, Peng

    2017-12-01

    A permanent magnet synchronous motor with radial magnetic circuit and built-in permanent magnet is designed for the electric vehicle. Finite element numerical calculation and experimental measurement are adopted to obtain the direct axis and quadrature axis inductance parameters of the motor which are vital important for the motor control. The calculation method is simple, the measuring principle is clear, the results of numerical calculation and experimental measurement are mutual confirmation. A quick and effective method is provided to obtain the direct axis and quadrature axis inductance parameters of the motor, and then improve the design of motor or adjust the control parameters of the motor controller.

  6. Biomass thermochemical gasification: Experimental studies and modeling

    Science.gov (United States)

    Kumar, Ajay

    The overall goals of this research were to study the biomass thermochemical gasification using experimental and modeling techniques, and to evaluate the cost of industrial gas production and combined heat and power generation. This dissertation includes an extensive review of progresses in biomass thermochemical gasification. Product gases from biomass gasification can be converted to biopower, biofuels and chemicals. However, for its viable commercial applications, the study summarizes the technical challenges in the gasification and downstream processing of product gas. Corn stover and dried distillers grains with solubles (DDGS), a non-fermentable byproduct of ethanol production, were used as the biomass feedstocks. One of the objectives was to determine selected physical and chemical properties of corn stover related to thermochemical conversion. The parameters of the reaction kinetics for weight loss were obtained. The next objective was to investigate the effects of temperature, steam to biomass ratio and equivalence ratio on gas composition and efficiencies. DDGS gasification was performed on a lab-scale fluidized-bed gasifier with steam and air as fluidizing and oxidizing agents. Increasing the temperature resulted in increases in hydrogen and methane contents and efficiencies. A model was developed to simulate the performance of a lab-scale gasifier using Aspen Plus(TM) software. Mass balance, energy balance and minimization of Gibbs free energy were applied for the gasification to determine the product gas composition. The final objective was to optimize the process by maximizing the net energy efficiency, and to estimate the cost of industrial gas, and combined heat and power (CHP) at a biomass feedrate of 2000 kg/h. The selling price of gas was estimated to be 11.49/GJ for corn stover, and 13.08/GJ for DDGS. For CHP generation, the electrical and net efficiencies were 37 and 86%, respectively for corn stover, and 34 and 78%, respectively for DDGS. For

  7. Experimental study on rapid embankment construction methods

    International Nuclear Information System (INIS)

    Hirano, Hideaki; Egawa, Kikuji; Hyodo, Kazuya; Kannoto, Yasuo; Sekimoto, Tsuyoshi; Kobayashi, Kokichi.

    1982-01-01

    In the construction of a thermal or nuclear power plant in a coastal area, shorter embankment construction period has come to be called for recently. This tendency is remarkable where construction period is limited due to meteorological or sea conditions. To meet this requirement, the authors have been conducting basic experimental studies on two methods for the rapid execution of embankment construction, that is, Steel Plate Cellular Bulkhead Embedding Method and Ship Hull Caisson Method. This paper presents an outline of the results of the experimental study on these two methods. (author)

  8. A theoretical and experimental study of microshield circuits

    Science.gov (United States)

    Dib, Nihad I.; Drayton, Rhonda F.; Katehi, Linda P. B.

    1993-05-01

    The novel type of monolithic planar transmission line presently studied theoretically and experimentally operates without via-holes or ground-equalizing air bridges; it also radiates less than conventional coplanar waveguides and furnishes a wide range of impedances in virtue of its many design parameters. The space-domain integral equation method is used to analyze several discontinuities of the proposed line. It is shown that the proposed line discontinuities radiate less than the corresponding coplanar waveguide cases.

  9. Studies of the experimental technologies of radiative opacity

    International Nuclear Information System (INIS)

    Zhang Jiyan; Yang Guohong; Ding Yaonan; Yang Jiamin; Li Jun; Zhang Wenhai; He Yingling; Wang Yaomei; Huang Haodong

    2004-12-01

    On the SHENGUANG-II laser facility, integrated experiment for opacity measurement was performed and related physical items were studies. In the experiment, some new-typed diagnosing device were also tested. The experiment includes three contents: (1) Investigation of the measurement technique of absorption spectra in the keV region; (2) Investigation of the measurement technique of dual point projection spectroscopy; (3) Investigation of the temperature and density parameters of the experimental samples. (authors)

  10. The study of multiple PET reconstructed parameter

    International Nuclear Information System (INIS)

    Yin, D. Y.; Tian, J.

    2000-01-01

    PET, compared with SPECT, uses some similar techniques in image reconstruction, on the other hand, there are some difference on the techniques. A phantom experiment was conducted and the result was evaluated objectively through quantitative analysis in order to find ideal filter and cutoff frequency (Fc) for clinical application. The PET phantom have 6 solid inserts (cold) in the upper half and 6 hollow ones (hot) in the lower part. The middle insert is 1cm in diameter, the outer five have diameters of 1 to 3cm respectively. The phantom filled with 111 MBq 18 FDG and studied with segmentation acquisition. 25 set of images were reconstructed using HANN, HAMM, PARZEN, BUTTERWORTH, BUTTERWORTH2 filter and 0.1, 0.2, 0.3, 0.4, 0.5 Fe successively.A ROI of 4*4 pixels was drawn over middle 1 cm, outer 1cm, 3 cm cold column area and background area, the ratio between the ROI of cold column and background was calculated to evaluate the image contrast. A ROI of 15*15 pixels was drawn on the background area to get s.d as a judgement of image noise. A profile curve was drawn on the hollow column of middle 1 cm and outer 1 cm and their FWHM were compared with the real diameter to reflect linearity. With the same Fc, the contrast using HANN and HAMM filter was superior to other filter, The effect of the filter on image noise is listed in high to low order as HAMM, HANN, BUTTERWORTH, PARZEN and BUTTERWORTH2. The higher Fc, the higher image noise. The FWHM will increases as the Fc value decreases. With same Fc, the FWHM of different filter from small to big is HAMM, BUTTERWORTH, HANN, PARZEN, BUTTERWORTH2. The outer FWHM is larger than the middle one. For brain image, we suggest HAMM and HANN with Fc 0.3, 0.4 For image demanding lower resolution, we suggest BUTTERWORTH with Fc 0.4, 0.5, 2. For hot image, we can increase Fc to get high resolution. The FWHM value closed to the real value when HANN, HANN with Fc 0.3 and BUTTERWORTH with Fc 0.2. The 5% difference of FWHM between

  11. Experimental verification of different parameters influencing the fatigue S/N-curve

    International Nuclear Information System (INIS)

    Roos, E.; Maile, K.; Herter, K.-H.; Schuler, X.

    2005-01-01

    For the construction, design and operation of nuclear components the appropriate technical codes and standards provide detailed stress analysis procedures, material data and a design philosophy which guarantees a reliable behavior throughout the specified lifetime. Especially for cyclic stress evaluation the different codes and standards provide different fatigue analyses procedures to be performed considering the various (specified or measured) loading histories which are of mechanical and/or thermal origin and the geometric complexities of the components. In order to fully understand the background of the fatigue analysis included in the codes and standards as well as of the fatigue design curves used as a limiting criteria (to determine the fatigue life usage factor), it is important to understand the history, background as well as the methodologies which are important for the design engineers to get reliable results. The design rules according to the technical codes and standards provide for explicit consideration of cyclic operation, using design fatigue curves of allowable alternating loads (allowable stress or strain amplitudes) vs. number of loading cycles (S/N-curves), specific rules for assessing the cumulative fatigue damage (cumulative fatigue life usage factor) caused by different specified or monitored load cycles. The influence of different factors like welds, environment, surface finish, temperature, mean stress and size must be taken into consideration. In the paper parameters influencing the S/N-curves used within a fatigue analysis, like different type of material, the surface finish, the temperature, the difference between unwelded and welded areas, the strain rate as well as the influences of notches are verified on the basis of experimental results obtained by specimens testing in the LCF regime for high strain amplitudes. Thus safety margins relevant for the assessment of fatigue life depending on the different influencing parameters are

  12. Measurements of relevant parameters in the formation of clathrate hydrates by a novel experimental apparatus

    Energy Technology Data Exchange (ETDEWEB)

    Arca, S.; Di Profio, P.; Germani, R.; Savelli, G. [Perugia Univ., CEMIN, Perugia (Italy). Dept. of Chemistry

    2008-07-01

    There is a growing interest in understanding the thermodynamics and kinetics of clathrate hydrate formation. This paper presented a study that involved the design, construction, calibration, and testing of a new apparatus that could obtain as many parameters as possible in a single formation batch and that could measure unexplored clathrate hydrate parameters. The apparatus was capable of measuring equilibrium phases involving gaseous components. The paper described the conceptual design as well as the chamber, pressure line, temperature control, liquid addition line, and conductometric probe. The paper also discussed data acquisition, stirring, measurement examples, and internal illumination and video monitoring. It was concluded that refining measurements, particularly those concerning kinetic characterizations, is important in order to clarify several uncertain kinetic behaviors of clathrate hydrates. 6 refs., 16 figs.

  13. CFD and experimental investigation of sloshing parameters for the safety assessment of HLM reactors

    Energy Technology Data Exchange (ETDEWEB)

    Myrillas, Konstantinos, E-mail: myrillas@vki.ac.be [von Karman Institute for Fluid Dynamics, Chaussée de Waterloo 72, B-1640 Rhode-St-Genèse (Belgium); Planquart, Philippe, E-mail: philippe.planquart@vki.ac.be [von Karman Institute for Fluid Dynamics, Chaussée de Waterloo 72, B-1640 Rhode-St-Genèse (Belgium); Simonini, Alessia, E-mail: Simonini@vki.ac.be [von Karman Institute for Fluid Dynamics, Chaussée de Waterloo 72, B-1640 Rhode-St-Genèse (Belgium); Buchlin, Jean-Marie, E-mail: buchlin@vki.ac.be [von Karman Institute for Fluid Dynamics, Chaussée de Waterloo 72, B-1640 Rhode-St-Genèse (Belgium); Schyns, Marc, E-mail: mschyns@SCKCEN.BE [SCK-CEN, Boeretang 200, B-2400 Mol (Belgium)

    2017-02-15

    Highlights: • Comparison of sloshing behavior in cylindrical tank using mercury and water. • Flow visualization of liquid sloshing in resonance case. • CFD simulations of sloshing with OpenFOAM, using the VOF method. • Qualitative and quantitative comparison of experimental and numerical results. • Evaluation of sloshing forces on the tank walls from numerical simulations. - Abstract: For the safety assessment of Heavy Liquid Metal nuclear reactors under seismic excitation, sloshing phenomena can be of great concern. The earthquake motions are transferred to the liquid coolant which oscillates inside the vessel, exerting additional forces on the walls and internal structures. The present study examines the case of MYRRHA, a multi-purpose experimental reactor with LBE as coolant, developed by SCK·CEN. The sloshing behavior of liquid metals is studied through a comparison between mercury and water in a cylindrical tank. Experimental investigation of sloshing is carried out using optical techniques with the shaking table facility SHAKESPEARE at the von Karman Institute. Emphasis is given on the resonance case, where maximum forces occur on the tank walls. The experimental cases are reproduced numerically with the CFD software OpenFOAM, using the VOF method to track the liquid interface. The non-linear nature of sloshing is observed through visualization, where swirling is shown in the resonance case. The complex behavior is well reproduced by the CFD simulations, providing good qualitative validation of the numerical tools. A quantitative comparison of the maximum liquid elevation inside the tank shows higher values for the liquid metal than for water. Some discrepancies are revealed in CFD results and the differences are quantified. From simulations it is verified that the forces scale with the density ratio, following similar evolution in time. Overall, water is demonstrated to be a valid option as a working liquid in order to evaluate the sloshing

  14. CFD and experimental investigation of sloshing parameters for the safety assessment of HLM reactors

    International Nuclear Information System (INIS)

    Myrillas, Konstantinos; Planquart, Philippe; Simonini, Alessia; Buchlin, Jean-Marie; Schyns, Marc

    2017-01-01

    Highlights: • Comparison of sloshing behavior in cylindrical tank using mercury and water. • Flow visualization of liquid sloshing in resonance case. • CFD simulations of sloshing with OpenFOAM, using the VOF method. • Qualitative and quantitative comparison of experimental and numerical results. • Evaluation of sloshing forces on the tank walls from numerical simulations. - Abstract: For the safety assessment of Heavy Liquid Metal nuclear reactors under seismic excitation, sloshing phenomena can be of great concern. The earthquake motions are transferred to the liquid coolant which oscillates inside the vessel, exerting additional forces on the walls and internal structures. The present study examines the case of MYRRHA, a multi-purpose experimental reactor with LBE as coolant, developed by SCK·CEN. The sloshing behavior of liquid metals is studied through a comparison between mercury and water in a cylindrical tank. Experimental investigation of sloshing is carried out using optical techniques with the shaking table facility SHAKESPEARE at the von Karman Institute. Emphasis is given on the resonance case, where maximum forces occur on the tank walls. The experimental cases are reproduced numerically with the CFD software OpenFOAM, using the VOF method to track the liquid interface. The non-linear nature of sloshing is observed through visualization, where swirling is shown in the resonance case. The complex behavior is well reproduced by the CFD simulations, providing good qualitative validation of the numerical tools. A quantitative comparison of the maximum liquid elevation inside the tank shows higher values for the liquid metal than for water. Some discrepancies are revealed in CFD results and the differences are quantified. From simulations it is verified that the forces scale with the density ratio, following similar evolution in time. Overall, water is demonstrated to be a valid option as a working liquid in order to evaluate the sloshing

  15. A combined experimental and theoretical study

    Indian Academy of Sciences (India)

    A combined theoretical and experimental study was also performed, which demonstrated that the clus- ters 1–3 with ... silica gel TLC plates (MERCK TLC Plates). The NMR .... tronic μ3-Se and maintains the same number of clus- ter valance ...

  16. Experimental study of collective processes in REB

    Energy Technology Data Exchange (ETDEWEB)

    Bogdanov, L Yu; Sominskij, G G [St. Petersburg Technical University (Russian Federation)

    1997-12-31

    The role of collective processes at relativistic electron beam formation and transportation was studied experimentally by using new low-disturbing techniques. In particular, local mirror-like enhancements of the external magnetic field were introduced and their influence of the beam space charge oscillations was investigated. The amplitude-frequency characteristics of the space charge oscillations in different parts of the drift channel were measured by a set of high-frequency probes. On the base of the collected experimental data two possible mechanisms of development of the beam space charge oscillations are discussed: the two-stream instability and the diocotron instability. (J.U.). 2 figs., 4 refs.

  17. Experimental study of the natural circulation phenomena

    International Nuclear Information System (INIS)

    Sabundjian, Gaiane; Andrade, Delvonei Alves de; Umbehaun, Pedro E.; Torres, Walmir M.; Castro, Alfredo Jose Alvim de; Belchior Junior, Antonio; Rocha, Ricardo Takeshi Vieira da; Damy, Osvaldo Luiz de Almeida; Torres, Eduardo

    2006-01-01

    The objective of this paper is to study the natural circulation in experimental loops and extend the results to nuclear facilities. New generation of compact nuclear power plants use the natural circulation as cooling and residual heat removal systems in case of accidents or shutdown. Lately the interest in this phenomenon, by scientific community, has increased. The experimental loop, described in this paper, was assembled at Escola Politecnica - USP at the Chemical Engineering Department. It is the goal to generate information to help with the understanding of the one and two phase natural circulation phenomena. Some experiments were performed with different levels of heat power and different flow of the cooling water at the secondary circuit. The data generated from these experiments are going to be used to validate some computational thermal hydraulic codes. Experimental results for one and two phase regimes are presented as well as the proposed model to simulate the flow regimes with the RELAP5 code. (author)

  18. A Comparative Study of Distribution System Parameter Estimation Methods

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Yannan; Williams, Tess L.; Gourisetti, Sri Nikhil Gup

    2016-07-17

    In this paper, we compare two parameter estimation methods for distribution systems: residual sensitivity analysis and state-vector augmentation with a Kalman filter. These two methods were originally proposed for transmission systems, and are still the most commonly used methods for parameter estimation. Distribution systems have much lower measurement redundancy than transmission systems. Therefore, estimating parameters is much more difficult. To increase the robustness of parameter estimation, the two methods are applied with combined measurement snapshots (measurement sets taken at different points in time), so that the redundancy for computing the parameter values is increased. The advantages and disadvantages of both methods are discussed. The results of this paper show that state-vector augmentation is a better approach for parameter estimation in distribution systems. Simulation studies are done on a modified version of IEEE 13-Node Test Feeder with varying levels of measurement noise and non-zero error in the other system model parameters.

  19. Damping parameter study of a perforated plate with bias flow

    Science.gov (United States)

    Mazdeh, Alireza

    role of LES for research studies concerned with damping properties of liners is limited to validation of other empirical or theoretical approaches. This research has shown that LES can go beyond that and can be used for performing parametric studies to characterize the sensitivity of acoustic properties of multi--perforated liners to the changes in the geometry and flow conditions and be used as a tool to design acoustic liners. The conducted research provides an insightful understanding about the contribution of different flow and geometry parameters such as perforated plate thickness, aperture radius, porosity factors and bias flow velocity. While the study agrees with previous observations obtained by analytical or experimental methods, it also quantifies the impact from these parameters on the acoustic impedance of perforated plate, a key parameter to determine the acoustic performance of any system. The conducted study has also explored the limitations and capabilities of commercial tool when are applied for performing simulation studies on damping properties of liners. The overall agreement between LES results and previous studies proves that commercial tools can be effectively used for these applications under certain conditions.

  20. The piezo-magnetic parameters of Terfenol-D: An experimental viewpoint

    International Nuclear Information System (INIS)

    Davino, D.; Giustiniani, A.; Visone, C.

    2012-01-01

    Magnetostrictive and all multifunctional materials have experienced in the last decades a growing technological interest. Several contributions, in the literature, propose the above-mentioned materials in innovative sensors and actuators both for bulk and MEMS devices. More recently, magnetostrictive materials have been proposed for energy harvesting applications by exploiting the so-called Villari effect. In this case, the behavior and the amplitude of the piezo-magnetic coefficients are an important element to evaluate the conversion efficiency. Aim of this paper is to study the experimental behavior of the piezo-magnetic coefficients of a commercial Terfenol-D rod under controlled conditions.

  1. Experimental studies of generalized parton distributions

    International Nuclear Information System (INIS)

    Kabuss, E.M.

    2014-01-01

    Generalized parton distributions (GPD) provide a new way to study the nucleon structure. Experimentally they can be accessed using hard exclusive processes such as deeply virtual Compton scattering and meson production. First insights to GPDs were already obtained from measurements at DESY, JLAB and CERN, while new ambitious studies are planned at the upgraded JLAB at 12 GeV and at CERN. Here, some emphasis will be put onto the planned COMPASS II programme. (author)

  2. Experimental Study on Abrasive Waterjet Polishing of Hydraulic Turbine Blades

    International Nuclear Information System (INIS)

    Khakpour, H; Birglenl, L; Tahan, A; Paquet, F

    2014-01-01

    In this paper, an experimental investigation is implemented on the abrasive waterjet polishing technique to evaluate its capability in polishing of surfaces and edges of hydraulic turbine blades. For this, the properties of this method are studied and the main parameters affecting its performance are determined. Then, an experimental test-rig is designed, manufactured and tested to be used in this study. This test-rig can be used to polish linear and planar areas on the surface of the desired workpieces. Considering the number of parameters and their levels, the Taguchi method is used to design the preliminary experiments. All experiments are then implemented according to the Taguchi L 18 orthogonal array. The signal-to-noise ratios obtained from the results of these experiments are used to determine the importance of the controlled polishing parameters on the final quality of the polished surface. The evaluations on these ratios reveal that the nozzle angle and the nozzle diameter have the most important impact on the results. The outcomes of these experiments can be used as a basis to design a more precise set of experiments in which the optimal values of each parameter can be estimated

  3. Mechanical properties of jennite: A theoretical and experimental study

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Juhyuk, E-mail: juhyuk.moon@stonybrook.edu [Civil Engineering Program, Department of Mechanical Engineering, Stony Brook University, NY 11794 (United States); Yoon, Seyoon [School of Engineering, Kings College, University of Aberdeen, Aberdeen AB24 3UE (United Kingdom); Monteiro, Paulo J.M. [Department of Civil and Environmental Engineering, University of California, Berkeley, CA 94720 (United States)

    2015-05-15

    The objective of this study is to determine the mechanical properties of jennite. To date, several hypotheses have been proposed to predict the structural properties of jennite. For the first time as reported herein, the isothermal bulk modulus of jennite was measured experimentally. Synchrotron-based high-pressure x-ray diffraction experiments were performed to observe the variation of lattice parameters under pressure. First-principles calculations were applied to compare with the experimental results and predict additional structural properties. Accurately measured isothermal bulk modulus herein (K{sub 0} = 64(2) GPa) and the statistical assessment on experimental and theoretical results suggest reliable mechanical properties of shear and Young's modulus, Poisson's ratio, and elastic tensor coefficients. Determination of these fundamental structural properties is the first step toward greater understanding of calcium–silicate–hydrate, as well as provides a sound foundation for forthcoming atomic level simulations.

  4. Experimental study of ERT monitoring ability to measure solute dispersion.

    Science.gov (United States)

    Lekmine, Grégory; Pessel, Marc; Auradou, Harold

    2012-01-01

    This paper reports experimental measurements performed to test the ability of electrical resistivity tomography (ERT) imaging to provide quantitative information about transport parameters in porous media such as the dispersivity α, the mixing front velocity u, and the retardation factor R(f) associated with the sorption or trapping of the tracers in the pore structure. The flow experiments are performed in a homogeneous porous column placed between two vertical set of electrodes. Ionic and dyed tracers are injected from the bottom of the porous media over its full width. Under such condition, the mixing front is homogeneous in the transverse direction and shows an S-shape variation in the flow direction. The transport parameters are inferred from the variation of the concentration curves and are compared with data obtained from video analysis of the dyed tracer front. The variations of the transport parameters obtained from an inversion performed by the Gauss-Newton method applied on smoothness-constrained least-squares are studied in detail. While u and R(f) show a relatively small dependence on the inversion procedure, α is strongly dependent on the choice of the inversion parameters. Comparison with the video observations allows for the optimization of the parameters; these parameters are found to be robust with respect to changes in the flow condition and conductivity contrast. © 2011, The Author(s). Ground Water © 2011, National Ground Water Association.

  5. Experimental study of structural response to earthquakes

    International Nuclear Information System (INIS)

    Clough, R.W.; Bertero, V.V.; Bouwkamp, J.G.; Popov, E.P.

    1975-01-01

    The objectives, methods, and some of the principal results obtained from experimental studies of the behavior of structures subjected to earthquakes are described. Although such investigations are being conducted in many laboratories throughout the world, the information presented deals specifically with projects being carried out at the Earthquake Engineering Research Center (EERC) of the University of California, Berkeley. A primary purpose of these investigations is to obtain detailed information on the inelastic response mechanisms in typical structural systems so that the experimentally observed performance can be compared with computer generated analytical predictions. Only by such comparisons can the mathematical models used in dynamic nonlinear analyses be verified and improved. Two experimental procedures for investigating earthquake structural response are discussed: the earthquake simulator facility which subjects the base of the test structure to acceleration histories similar to those recorded in actual earthquakes, and systems of hydraulic rams which impose specified displacement histories on the test components, equivalent to motions developed in structures subjected to actual'quakes. The general concept and performance of the 20ft square EERC earthquake simulator is described, and the testing of a two story concrete frame building is outlined. Correlation of the experimental results with analytical predictions demonstrates that satisfactory agreement can be obtained only if the mathematical model incorporates a stiffness deterioration mechanism which simulates the cracking and other damage suffered by the structure

  6. Experimental study of highly viscous impinging jets

    Energy Technology Data Exchange (ETDEWEB)

    Gomon, M. [Univ. of Texas, Austin, TX (United States). Dept. of Mechanical Engineering

    1998-12-01

    The objective of this research is to study the behavior of highly viscous gravity-driven jets filling a container. Matters of interest are the formation of voids in the fluid pool during the filling process and the unstable behavior of the fluid in the landing region which manifests itself as an oscillating motion. The working fluids used in this research are intended to simulate the flow behavior of molten glass. Qualitative and quantitative results are obtained in a parametric study. The fraction of voids present in the fluid pool after the filling of the container is measured for different parameter values of viscosity and mass flow rate. Likewise, frequencies of the oscillating jet are measured. Results are inconclusive with regard to a correlation between parameter settings and void fractions. As for frequencies, power law correlations are established.

  7. Experimental study of highly viscous impinging jets

    International Nuclear Information System (INIS)

    Gomon, M.

    1998-12-01

    The objective of this research is to study the behavior of highly viscous gravity-driven jets filling a container. Matters of interest are the formation of voids in the fluid pool during the filling process and the unstable behavior of the fluid in the landing region which manifests itself as an oscillating motion. The working fluids used in this research are intended to simulate the flow behavior of molten glass. Qualitative and quantitative results are obtained in a parametric study. The fraction of voids present in the fluid pool after the filling of the container is measured for different parameter values of viscosity and mass flow rate. Likewise, frequencies of the oscillating jet are measured. Results are inconclusive with regard to a correlation between parameter settings and void fractions. As for frequencies, power law correlations are established

  8. Experimental determination of fuel element parameters; Eksperimentalno odredjivanje parametara gorivnog elementa

    Energy Technology Data Exchange (ETDEWEB)

    Takac, S; Zdravkoovic, Z; Ivkovic, N; Sotic, O; Krcevinac, S [Boris Kidric Institute of Nuclear Sciences Vinca, Beograd (Yugoslavia)

    1968-04-15

    The objective of the experiments described was to study the applicability of heterogeneous reactor theory. The properties of the following fuel elements were measured: natural uranium rod, 2% enriched uranium tube; natural uranium oxide fuel cluster. Thermal neutron flux density in and around a single fuel element, {gamma} thermal constant factor, and {eta} multiplication constant were analyzed for fuel cluster dependent on the lattice pitch of fuel pins in the cluster. Measurement {gamma} and {eta} values were compared to calculation results obtained by TER-3 code (Amoyal-Benoist method). Special attention was devoted to improvement of experimental technique and study of micro perturbation in simple and complex elementary cells with the aim to obtain exact thermal neutron flux distribution in reactor cell.

  9. Experimental investigation into effect of cutting parameters on surface integrity of hardened tool steel

    Science.gov (United States)

    Bashir, K.; Alkali, A. U.; Elmunafi, M. H. S.; Yusof, N. M.

    2018-04-01

    Recent trend in turning hardened materials have gained popularity because of its immense machinability benefits. However, several machining processes like thermal assisted machining and cryogenic machining have reveal superior machinability benefits over conventional dry turning of hardened materials. Various engineering materials have been studied. However, investigations on AISI O1 tool steel have not been widely reported. In this paper, surface finish and surface integrity dominant when hard turning AISI O1 tool steel is analysed. The study is focused on the performance of wiper coated ceramic tool with respect to surface roughness and surface integrity of hardened tool steel. Hard turned tool steel was machined at varying cutting speed of 100, 155 and 210 m/min and feed rate of 0.05, 0.125 and 0.20mm/rev. The depth of cut of 0.2mm was maintained constant throughout the machining trials. Machining was conducted using dry turning on 200E-axis CNC lathe. The experimental study revealed that the surface finish is relatively superior at higher cutting speed of 210m/min. The surface finish increases when cutting speed increases whereas surface finish is generally better at lower feed rate of 0.05mm/rev. The experimental study conducted have revealed that phenomena such as work piece vibration due to poor or improper mounting on the spindle also contributed to higher surface roughness value of 0.66Ra during turning at 0.2mm/rev. Traces of white layer was observed when viewed with optical microscope which shows evidence of cutting effects on the turned work material at feed rate of 0.2 rev/min

  10. Experimental fretting-wear studies of steam generator materials

    International Nuclear Information System (INIS)

    Fisher, N.J.; Chow, A.B.; Weckwerth, M.K.

    1994-01-01

    Flow-induced vibration of steam generator tubes results in fretting-wear damage due to impacting and rubbing of the tubes against their supports. This damage can be predicted by computing tube response to flow-induced excitation forces using analytical techniques, and then relating this response to resultant wear damage using experimentally-derived wear coefficients. Fretting-wear of steam generator materials has been studied experimentally at Chalk River Laboratories for two decades. Tests are conducted in machines that simulate steam generator environmental conditions and tube-to-support dynamic interactions. Different tube and support materials, tube-to-support clearances and tube support geometries have been studied. As well, the effect of environmental conditions, such as temperature, oxygen content, pH and chemistry control additive, have been investigated. Early studies showed that damage was related to contact force as long as other parameters, such as geometry and motion were held constant. Later studies have shown that damage is related to a parameter called work-rate, which combines both contact force and sliding distance. Results of short- and long-term fretting-wear tests for CANDU steam generator materials at realistic environmental conditions are presented. These results demonstrate that work-rate is appropriate correlating parameter for impact-sliding interaction

  11. Experimental Investigation and Optimization of TIG Welding Parameters on Aluminum 6061 Alloy Using Firefly Algorithm

    Science.gov (United States)

    Kumar, Rishi; Mevada, N. Ramesh; Rathore, Santosh; Agarwal, Nitin; Rajput, Vinod; Sinh Barad, AjayPal

    2017-08-01

    To improve Welding quality of aluminum (Al) plate, the TIG Welding system has been prepared, by which Welding current, Shielding gas flow rate and Current polarity can be controlled during Welding process. In the present work, an attempt has been made to study the effect of Welding current, current polarity, and shielding gas flow rate on the tensile strength of the weld joint. Based on the number of parameters and their levels, the Response Surface Methodology technique has been selected as the Design of Experiment. For understanding the influence of input parameters on Ultimate tensile strength of weldment, ANOVA analysis has been carried out. Also to describe and optimize TIG Welding using a new metaheuristic Nature - inspired algorithm which is called as Firefly algorithm which was developed by Dr. Xin-She Yang at Cambridge University in 2007. A general formulation of firefly algorithm is presented together with an analytical, mathematical modeling to optimize the TIG Welding process by a single equivalent objective function.

  12. Experimental studies of nonlinear beam dynamics

    International Nuclear Information System (INIS)

    Caussyn, D.D.; Ball, M.; Brabson, B.; Collins, J.; Curtis, S.A.; Derenchuck, V.; DuPlantis, D.; East, G.; Ellison, M.; Ellison, T.; Friesel, D.; Hamilton, B.; Jones, W.P.; Lamble, W.; Lee, S.Y.; Li, D.; Minty, M.G.; Sloan, T.; Xu, G.; Chao, A.W.; Ng, K.Y.; Tepikian, S.

    1992-01-01

    The nonlinear beam dynamics of transverse betatron oscillations were studied experimentally at the Indiana University Cyclotron Facility cooler ring. Motion in one dimension was measured for betatron tunes near the third, fourth, fifth, and seventh integer resonances. This motion is described by coupling between the transverse modes of motion and nonlinear field errors. The Hamiltonian for nonlinear particle motion near the third- and fourth-integer-resonance conditions has been deduced

  13. Magneto-Rheological Damper - An Experimental Study

    OpenAIRE

    Lozoya-Santos , Jorge De-Jesus; Morales-Menéndez , Rubén; Ramirez-Mendoza , Ricardo; Tudon-Martınez , Juan ,; Sename , Olivier; Dugard , Luc

    2012-01-01

    International audience; A Magneto-Rheological (MR) damper is evaluated under exhaustive experimental scenarios, generating a complete database. The obtained database includes classical tests and new proposals emphasizing the frequency contents. It also includes the impact of the electric current fluctuations. The variety of the performed experiments allows to study the MR damper force dynamics. A brief description of the damper behavior and a categorization of experiments based on driving con...

  14. Experimental Setups for Single Event Effect Studies

    OpenAIRE

    N. H. Medina; V. A. P. Aguiar; N. Added; F. Aguirre; E. L. A. Macchione; S. G. Alberton; M. A. G. Silveira; J. Benfica; F. Vargas; B. Porcher

    2016-01-01

    Experimental setups are being prepared to test and to qualify electronic devices regarding their tolerance to Single Event Effect (SEE). A multiple test setup and a new beam line developed especially for SEE studies at the São Paulo 8 UD Pelletron accelerator were prepared. This accelerator produces proton beams and heavy ion beams up to 107Ag. A Super conducting Linear accelerator, which is under construction, may fulfill all of the European Space Agency requirements to qualify electronic...

  15. Theoretical and experimental studies of elementary particles

    International Nuclear Information System (INIS)

    Bodek, A.; Ferbel, T.; Melissinos, A.C.; Olsen, S.L.; Slattery, P.; Tipton, P.; Das, A.; Hagen, C.R.; Rajeev, S.G.; Okubo, S.

    1991-01-01

    This report discusses: Fixed target experimentation at Fermilab; the D-zero collider experiment at Fermilab; deep inelastic lepton nucleon scattering; non-accelerator experiments and non-linear QED; the AMY experiment at TRISTAN and other activities at KEK; the collider detector at Fermilab; laser switched linac; preparations for experiments at the SSC; search for massive stable particles; and the Advanced Study Institute on techniques and concepts of high energy physics

  16. Determination of heat transfer parameters by use of finite integral transform and experimental data for regular geometric shapes

    Science.gov (United States)

    Talaghat, Mohammad Reza; Jokar, Seyyed Mohammad

    2017-12-01

    This article offers a study on estimation of heat transfer parameters (coefficient and thermal diffusivity) using analytical solutions and experimental data for regular geometric shapes (such as infinite slab, infinite cylinder, and sphere). Analytical solutions have a broad use in experimentally determining these parameters. Here, the method of Finite Integral Transform (FIT) was used for solutions of governing differential equations. The temperature change at centerline location of regular shapes was recorded to determine both the thermal diffusivity and heat transfer coefficient. Aluminum and brass were used for testing. Experiments were performed for different conditions such as in a highly agitated water medium ( T = 52 °C) and in air medium ( T = 25 °C). Then, with the known slope of the temperature ratio vs. time curve and thickness of slab or radius of the cylindrical or spherical materials, thermal diffusivity value and heat transfer coefficient may be determined. According to the method presented in this study, the estimated of thermal diffusivity of aluminum and brass is 8.395 × 10-5 and 3.42 × 10-5 for a slab, 8.367 × 10-5 and 3.41 × 10-5 for a cylindrical rod and 8.385 × 10-5 and 3.40 × 10-5 m2/s for a spherical shape, respectively. The results showed there is close agreement between the values estimated here and those already published in the literature. The TAAD% is 0.42 and 0.39 for thermal diffusivity of aluminum and brass, respectively.

  17. Experimental investigation and optimization of welding process parameters for various steel grades using NN tool and Taguchi method

    Science.gov (United States)

    Soni, Sourabh Kumar; Thomas, Benedict

    2018-04-01

    The term "weldability" has been used to describe a wide variety of characteristics when a material is subjected to welding. In our analysis we perform experimental investigation to estimate the tensile strength of welded joint strength and then optimization of welding process parameters by using taguchi method and Artificial Neural Network (ANN) tool in MINITAB and MATLAB software respectively. The study reveals the influence on weldability of steel by varying composition of steel by mechanical characterization. At first we prepare the samples of different grades of steel (EN8, EN 19, EN 24). The samples were welded together by metal inert gas welding process and then tensile testing on Universal testing machine (UTM) was conducted for the same to evaluate the tensile strength of the welded steel specimens. Further comparative study was performed to find the effects of welding parameter on quality of weld strength by employing Taguchi method and Neural Network tool. Finally we concluded that taguchi method and Neural Network Tool is much efficient technique for optimization.

  18. Determining experimentally the parameters of the unsteady thermal behaviour of homogeneously layered walls by the reference plates method

    International Nuclear Information System (INIS)

    Beron, Rodolphe

    1988-01-01

    In this work, we introduce an experimental determination method of parameters which are characteristics of the transfer functions of walls in buildings by the use of an easy equipment which use needs no significant constraint. This method called 'reference plates method' is based on the working out of the thermo-grams which result from any thermal perturbation. The first part of our work deals with the theoretical development of the methods of working out the measures used for both single-Iayered and multi-layered walls. The second part discusses the applying of the method on single-Iayered sample. The values of thermophysical characteristics of the wall is based on the working out of the heat equation written in terms an integral transformation which we take as Laplace's transformation. The case of multi-Iayered wall which we discuss in the third part, lead to the determination of 'z transforms coefficients' of the transfer functions of the studied wall. In addition to the theoretical study, we analyse the results of prospective experiments in the fourth part of our work and show the usefulness of such a measurement method. The last part is devoted to the presentation of the application of our work to the determination of thermal parameters of more general wall's configurations. (author) [fr

  19. Colloid facilitated transport in fractured rocks: parameter estimation and comparison with experimental data

    International Nuclear Information System (INIS)

    Viswanthan, H.S.; Wolfsberg, A.V.; Reimus, P.W.; Ware, D.; Lu, G.

    2003-01-01

    Colloid-facilitated migration of plutonium in fractured rock has been implicated in both field and laboratory studies. Other reactive radionuclides may also experience enhanced mobility due to groundwater colloids. Model prediction of this process is necessary for assessment of contaminant boundaries in systems for which radionuclides are already in the groundwater and for performance assessment of potential repositories for radioactive waste. Therefore, a reactive transport model is developed and parameterized using results from controlled laboratory fracture column experiments. Silica, montmorillonite and clinoptilolite colloids are used in the experiments along with plutonium and Tritium. The goal of the numerical model is to identify and parameterize the physical and chemical processes that affect the colloid-facilitated transport of plutonium in the fractures. The parameters used in this model are similar in form to those that might be used in a field-scale transport model

  20. Experimental investigations on steel-concrete composite columns for varying parameters

    Science.gov (United States)

    Aparna, V.; Vivek, D.; Neelima, Kancharla; Karthikeyan, B.

    2017-07-01

    In this study, the experimental investigations on steel tubes filled with different types of concrete are presented. Steel tubes filled with fibre reinforced concrete using lathe waste and steel tube with concerned confined with steel mesh were investigated. The combinations were compared with steel tubes with conventional concrete. A total of 4 concrete filled steel tube (CFST) combinations were made with tubes of diameter 100 mm with wall thickness 1.6 mm and a height of 300 mm. Axial compression test to examine the resisting capacity of the columns and push-out test for noting the bond strength were performed. Coupon tests were also conducted to determine the mechanical properties of steel. The structural behaviour of the composite columns was evaluated from on the test results. It was observed that steel tube filled fibre reinforced possessed better bond strength and resistance to axial load.

  1. Experimental studies of gravitation and feebler forces

    International Nuclear Information System (INIS)

    Cowsik, R.

    1993-01-01

    The theoretical motivations and the experimental context pertaining to the recent experimental studies of the Weak equivalence Principle and the open-quotes Fifth Forceclose quotes are reviewed briefly. With such a backdrop, the innovative design and the technical details of the several new experiments in this area are presented with a special emphasis on the experiments underway at Gauribidanur, situated on the Deccan Plateau. These experiments jointly rule out the existence of any new forces coupling to baryon or lepton number with a coupling greater than about 10 -4 of gravitation per a.m.u. at ranges of about 0.5m and longer. In a few years the author hopes to test the weak equivalence principle with sensitivity exceeding 10 -13

  2. Experimental study of natural circulation circuit

    Energy Technology Data Exchange (ETDEWEB)

    Lemos, Wanderley F.; Su, Jian, E-mail: wlemos@lasme.coppe.ufrj.br, E-mail: sujian@lasme.coppe.ufrj.br [Coordenacao dos Programas de Pos-Graduacao de Engenharia (LASME/COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Lab. de Simulacao e Metodos Numericos; Faccini, Jose L.H., E-mail: faccini@ien.gov.br [Instituto de Engenharia Nuclear (LTE/IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Lab. de Termo-Hidraulica Experimental

    2011-07-01

    This work presents an experimental study about fluid flows behavior in natural circulation, under conditions of single-phase flow. The experiment was performed through experimental thermal-hydraulic circuit built at IEN. This test equipment has performance similar to passive system of residual heat removal present in Advanced Pressurized Water Reactors (APWR). This experimental study aims to observing and analyzing the natural circulation phenomenon, using this experimental circuit that was dimensioned and built based on concepts of similarity and scale. This philosophy allows the analysis of natural circulation behavior in single-phase flow conditions proportionally to the functioning real conditions of a nuclear reactor. The experiment was performed through procedures to initialization of hydraulic feeding of primary and secondary circuits and electrical energizing of resistors installed inside heater. Power controller has availability to adjust values of electrical power to feeding resistors, in order to portray several conditions of energy decay of nuclear reactor in a steady state. Data acquisition system allows the measurement and monitoring of the evolution of the temperature in various points through thermocouples installed in strategic points along hydraulic circuit. The behavior of the natural circulation phenomenon was monitored by graphical interface on computer screen, showing the temperature evolutions of measuring points and results stored in digital spreadsheets. The results stored in digital spreadsheets allowed the getting of data to graphic construction and discussion about natural circulation phenomenon. Finally, the calculus of Reynolds number allowed the establishment for a correlation of friction in function of geometric scales of length, heights and cross section of tubing, considering a natural circulation flow throughout in the region of hot leg. (author)

  3. Experimental study of natural circulation circuit

    International Nuclear Information System (INIS)

    Lemos, Wanderley F.; Su, Jian; Faccini, Jose L.H.

    2011-01-01

    This work presents an experimental study about fluid flows behavior in natural circulation, under conditions of single-phase flow. The experiment was performed through experimental thermal-hydraulic circuit built at IEN. This test equipment has performance similar to passive system of residual heat removal present in Advanced Pressurized Water Reactors (APWR). This experimental study aims to observing and analyzing the natural circulation phenomenon, using this experimental circuit that was dimensioned and built based on concepts of similarity and scale. This philosophy allows the analysis of natural circulation behavior in single-phase flow conditions proportionally to the functioning real conditions of a nuclear reactor. The experiment was performed through procedures to initialization of hydraulic feeding of primary and secondary circuits and electrical energizing of resistors installed inside heater. Power controller has availability to adjust values of electrical power to feeding resistors, in order to portray several conditions of energy decay of nuclear reactor in a steady state. Data acquisition system allows the measurement and monitoring of the evolution of the temperature in various points through thermocouples installed in strategic points along hydraulic circuit. The behavior of the natural circulation phenomenon was monitored by graphical interface on computer screen, showing the temperature evolutions of measuring points and results stored in digital spreadsheets. The results stored in digital spreadsheets allowed the getting of data to graphic construction and discussion about natural circulation phenomenon. Finally, the calculus of Reynolds number allowed the establishment for a correlation of friction in function of geometric scales of length, heights and cross section of tubing, considering a natural circulation flow throughout in the region of hot leg. (author)

  4. Pulsed total dose damage effect experimental study on EPROM

    International Nuclear Information System (INIS)

    Luo Yinhong; Yao Zhibin; Zhang Fengqi; Guo Hongxia; Zhang Keying; Wang Yuanming; He Baoping

    2011-01-01

    Nowadays, memory radiation effect study mainly focus on functionality measurement. Measurable parameters is few in china. According to the present situation, threshold voltage testing method was presented on floating gate EPROM memory. Experimental study of pulsed total dose effect on EPROM threshold voltage was carried out. Damage mechanism was analysed The experiment results showed that memory cell threshold voltage negative shift was caused by pulsed total dose, memory cell threshold voltage shift is basically coincident under steady bias supply and no bias supply. (authors)

  5. Experimental and numerical investigations of oscillations in extracted material parameters for finite Bragg stacks using the NRW method

    DEFF Research Database (Denmark)

    Clausen, Niels Christian Jerichau; Arslanagic, Samel; Breinbjerg, Olav

    2012-01-01

    A 1D dielectric finite Bragg stack situated in a rectangular waveguide and illuminated by the fundamental TE10 mode is examined analytically, numerically, and experimentally. Calculated as well as measured scattering parameters are used to extract the effective/equivalent material parameters...... for three specific configurations of its constituent unit cell. Particular attention is devoted to the absence/presence of certain oscillations in the extracted material parameters, depending on the unit cell configuration. The results for the finite Bragg stack are further verified to agree with those...... of an infinite Bragg stack, for which the dispersion equation is used in conjunction with the Floquet-Bloch harmonics expansion to extract the material parameters. It is shown that the extracted material parameters for the finite and infinite Bragg stacks agree for the symmetric unit cell configuration....

  6. Gas migration in KBS-3 buffer bentonite. Sensitivity of test parameters to experimental boundary conditions

    International Nuclear Information System (INIS)

    Harrington, J.F.; Horseman, S.T.

    2003-01-01

    In the current Swedish repository design concept, hydrogen gas can be generated inside a waste canister by anaerobic corrosion of the ferrous metal liner. If the gas generation rate exceeds the diffusion rate of gas molecules in the buffer porewater, gas will accumulate in the void-space of a canister until its pressure becomes large enough for it to enter the bentonite as a discrete gaseous phase. Three long tenn gas injection tests have been performed on cylinders of pre-compacted MX80 bentonite. Two of these tests were undertaken using a custom-designed constant volume and radial flow (CVRF) apparatus. Gas was injected at a centrally located porous filter installed in the clay before hydration. Arrangements were made for gas to flow to three independently monitored sink-filter arrays mounted around the specimen. Axial and radial total stresses and internal porewater pressures were continuously monitored. Breakthrough and peak gas pressures were substantially larger than the sum of the swelling pressure and the external porewater. The third test was performed. using an apparatus which radially constrains the specimen during gas flow. Observed sensitivity of the breakthrough and peak gas pressures to the test boundary conditions suggests that gas entry must be accompanied by dilation of the bentonite fabric. In other words, there is a tendency for the volume of the specimen to increase during this process. The experimental evidence is consistent with the flow of gas along a relatively small number of crack-like pathways which propagate through the clay as gas pressure increases. Gas entry and breakthrough under constant volume boundary conditions causes a substantial increase in the total stress and the internal porewater pressure. It is possible to determine the point at which gas enters the clay by monitoring changes in these parameters. Localisation of gas flow within multiple pathways results, in nonuniform discharge rates at the sinks. When gas injection

  7. Gas migration in KBS-3 buffer bentonite. Sensitivity of test parameters to experimental boundary conditions

    Energy Technology Data Exchange (ETDEWEB)

    Harrington, J.F.; Horseman, S.T. [British Geological Survey, Nottingham (United Kingdom)

    2003-01-01

    In the current Swedish repository design concept, hydrogen gas can be generated inside a waste canister by anaerobic corrosion of the ferrous metal liner. If the gas generation rate exceeds the diffusion rate of gas molecules in the buffer porewater, gas will accumulate in the void-space of a canister until its pressure becomes large enough for it to enter the bentonite as a discrete gaseous phase. Three long tenn gas injection tests have been performed on cylinders of pre-compacted MX80 bentonite. Two of these tests were undertaken using a custom-designed constant volume and radial flow (CVRF) apparatus. Gas was injected at a centrally located porous filter installed in the clay before hydration. Arrangements were made for gas to flow to three independently monitored sink-filter arrays mounted around the specimen. Axial and radial total stresses and internal porewater pressures were continuously monitored. Breakthrough and peak gas pressures were substantially larger than the sum of the swelling pressure and the external porewater. The third test was performed. using an apparatus which radially constrains the specimen during gas flow. Observed sensitivity of the breakthrough and peak gas pressures to the test boundary conditions suggests that gas entry must be accompanied by dilation of the bentonite fabric. In other words, there is a tendency for the volume of the specimen to increase during this process. The experimental evidence is consistent with the flow of gas along a relatively small number of crack-like pathways which propagate through the clay as gas pressure increases. Gas entry and breakthrough under constant volume boundary conditions causes a substantial increase in the total stress and the internal porewater pressure. It is possible to determine the point at which gas enters the clay by monitoring changes in these parameters. Localisation of gas flow within multiple pathways results, in nonuniform discharge rates at the sinks. When gas injection

  8. DEM modeling of ball mills with experimental validation: influence of contact parameters on charge motion and power draw

    Science.gov (United States)

    Boemer, Dominik; Ponthot, Jean-Philippe

    2017-01-01

    Discrete element method simulations of a 1:5-scale laboratory ball mill are presented in this paper to study the influence of the contact parameters on the charge motion and the power draw. The position density limit is introduced as an efficient mathematical tool to describe and to compare the macroscopic charge motion in different scenarios, i.a. with different values of the contact parameters. While the charge motion and the power draw are relatively insensitive to the stiffness and the damping coefficient of the linear spring-slider-damper contact law, the coefficient of friction has a strong influence since it controls the sliding propensity of the charge. Based on the experimental calibration and validation by charge motion photographs and power draw measurements, the descriptive and predictive capabilities of the position density limit and the discrete element method are demonstrated, i.e. the real position of the charge is precisely delimited by the respective position density limit and the power draw can be predicted with an accuracy of about 5 %.

  9. Experimental Investigation on the Fatigue Mechanical Properties of Intermittently Jointed Rock Models Under Cyclic Uniaxial Compression with Different Loading Parameters

    Science.gov (United States)

    Liu, Yi; Dai, Feng; Dong, Lu; Xu, Nuwen; Feng, Peng

    2018-01-01

    Intermittently jointed rocks, widely existing in many mining and civil engineering structures, are quite susceptible to cyclic loading. Understanding the fatigue mechanism of jointed rocks is vital to the rational design and the long-term stability analysis of rock structures. In this study, the fatigue mechanical properties of synthetic jointed rock models under different cyclic conditions are systematically investigated in the laboratory, including four loading frequencies, four maximum stresses, and four amplitudes. Our experimental results reveal the influence of the three cyclic loading parameters on the mechanical properties of jointed rock models, regarding the fatigue deformation characteristics, the fatigue energy and damage evolution, and the fatigue failure and progressive failure behavior. Under lower loading frequency or higher maximum stress and amplitude, the jointed specimen is characterized by higher fatigue deformation moduli and higher dissipated hysteresis energy, resulting in higher cumulative damage and lower fatigue life. However, the fatigue failure modes of jointed specimens are independent of cyclic loading parameters; all tested jointed specimens exhibit a prominent tensile splitting failure mode. Three different crack coalescence patterns are classified between two adjacent joints. Furthermore, different from the progressive failure under static monotonic loading, the jointed rock specimens under cyclic compression fail more abruptly without evident preceding signs. The tensile cracks on the front surface of jointed specimens always initiate from the joint tips and then propagate at a certain angle with the joints toward the direction of maximum compression.

  10. Determination of low-energy parameters of neutron-proton scattering in the the shape-parameter approximation from present-day experimental data

    International Nuclear Information System (INIS)

    Babenko, V. A.; Petrov, N. M.

    2010-01-01

    On the basis of the total cross sections for neutron-proton scattering in the region of laboratory energies below 150 keV, the value of σ 0 = 20.4288(146) b was obtained for the total cross sections for neutron-proton scattering at zero energy. This value is in very good agreement with the experimental cross sections obtained by Houke and Hurst, but it is at odds with Dilg's experimental cross section. By using the value that we found for σ 0 and the experimental values of the neutron-proton coherent scattering length f, the deuteron binding energy ε t , the deuteron effective radius ρ t (-ε t , -ε t ), and the total cross section in the region of energies below 5 MeV, the following values were found in the shape-parameter approximation for the low-energy parameters of neutron-proton scattering in the spin-triplet and spin-singlet states: a t = 5.4114(27) fm, r 0t = 1.7606(35) fm, v 2t = 0.157 fm 3 , a s = -23.7154(80) fm, r 0s = 2.706(67) fm, and v 2s = 0.491 fm 3 .

  11. Study of excitation energy dependence of nuclear level density parameter

    International Nuclear Information System (INIS)

    Mohanto, G.; Nayak, B.K.; Saxena, A.

    2016-01-01

    In the present study, we have populated CN by fusion reaction and excitation energy of the intermediate nuclei is determined after first chance α-emission to investigate excitation energy dependence of the NLD parameter. Evaporated neutron spectra were measured following alpha evaporation for obtaining NLD parameter for the reaction 11 B + 197 Au, populating CN 208 Po. This CN after evaporating an α-particle populates intermediate nucleus 204 Pb. The 204 Pb has magic number of Z=82. Our aim is to study the excitation energy dependence of NLD parameter for closed shell nuclei

  12. Fluorene: An extended experimental thermodynamic study

    International Nuclear Information System (INIS)

    Monte, Manuel J.S.; Pinto, Sónia P.; Lobo Ferreira, Ana I.M.C.; Amaral, Luísa M.P.F.; Freitas, Vera L.S.; Ribeiro da Silva, Maria D.M.C.

    2012-01-01

    Highlights: ► Experimental results of an extended thermodynamic study on fluorene are presented. ► Enthalpy of combustion and vapor pressures of liquid and crystalline phase were measured. ► Enthalpy of sublimation was derived from three different experimental methods. ► New values of enthalpies of sublimation and of formation of fluorene are recommended. - Abstract: This work reports new experimental thermodynamic results on fluorene. Vapor pressures of both crystalline and liquid phases were measured using a pressure gauge (capacitance diaphragm manometer) and Knudsen effusion methods over a wide temperature range (292.20 to 412.16) K yielding accurate determination of enthalpy and entropy of sublimation and of vaporization. The enthalpy of sublimation was also determined using Calvet microcalorimetry. The enthalpy of fusion was derived from vapor pressure results and from d.s.c. experiments. Static bomb calorimetry was used to determine the enthalpy of combustion of fluorene from which the standard enthalpy of formation in the crystalline phase was calculated. The enthalpy of formation in the gaseous phase was calculated combining the result derived for the crystalline phase with the enthalpy of sublimation.

  13. Experimental percolation studies of random networks

    Science.gov (United States)

    Feinerman, A.; Weddell, J.

    2017-06-01

    This report establishes an experimental method of studying electrically percolating networks at a higher resolution than previously implemented. This method measures the current across a conductive sheet as a function of time as elliptical pores are cut into the sheet. This is done utilizing a Universal Laser System X2-600 100 W CO2 laser system with a 76 × 46 cm2 field and 394 dpc (dots/cm) resolution. This laser can cut a random system of elliptical pores into a conductive sheet with a potential voltage applied across it and measures the current versus time. This allows for experimental verification of a percolation threshold as a function of the ellipse's aspect ratio (minor/major diameter). We show that as an ellipse's aspect ratio approaches zero, the percolation threshold approaches one. The benefit of this method is that it can experimentally measure the effect of removing small pores, as well as pores with complex geometries, such as an asterisk from a conductive sheet.

  14. Experimental study of filter cake formation on different filter media

    International Nuclear Information System (INIS)

    Saleem, M.

    2009-01-01

    Removal of particulate matter from gases generated in the process industry is important for product recovery as well as emission control. Dynamics of filtration plant depend on operating conditions. The models, that predict filter plant behaviour, involve empirical resistance parameters which are usually derived from limited experimental data and are characteristics of the filter media and filter cake (dust deposited on filter medium). Filter cake characteristics are affected by the nature of filter media, process parameters and mode of filter regeneration. Removal of dust particles from air is studied in a pilot scale jet pulsed bag filter facility resembling closely to the industrial filters. Limestone dust and ambient air are used in this study with two widely different filter media. All important parameters like pressure drop, gas flow rate, dust settling, are recorded continuously at 1s interval. The data is processed for estimation of the resistance parameters. The pressure drop rise on test filter media is compared. Results reveal that the surface of filter media has an influence on pressure drop rise (concave pressure drop rise). Similar effect is produced by partially jet pulsed filter surface. Filter behaviour is also simulated using estimated parameters and a simplified model and compared with the experimental results. Distribution of cake area load is therefore an important aspect of jet pulse cleaned bag filter modeling. Mean specific cake resistance remains nearly constant on thoroughly jet pulse cleaned membrane coated filter bags. However, the trend can not be confirmed without independent cake height and density measurements. Thus the results reveal the importance of independent measurements of cake resistance. (author)

  15. Experimental Platform for measuring the parameters of magnetization of a transformer in a quasi-static transitional regime

    International Nuclear Information System (INIS)

    Milovanski, Vasil; , Blagoevgrad (Bulgaria))" data-affiliation=" (HMS “Acad. S. P. Corolov, Blagoevgrad (Bulgaria))" >Stoyanov, Krasimir; Milovanska, Stefani

    2013-01-01

    Some opportunities for development of an experimental module for magnetic research have been examined in the current paper. The goal is to attain a more accurate reading of the measured electrical signals which are directly related to the magnetic parameters and characteristics of the ferromagnetic material

  16. Technological parameter and experimental set-up influences on latch-up triggering level in bulk CMOS device

    International Nuclear Information System (INIS)

    Dubuc, J.P.; Azais, B.; Murcia, M. de

    1994-01-01

    This paper deals with experimental and simulation results on latch-up triggered by an electrical or X-rays pulse in CMOS/bulk devices. Test condition influences as well as the great importance of process parameters on latch-up immunity are emphasized. (author). 10 refs., 19 figs., 1 tab

  17. Wines: water inelastic neutron scattering experimental study

    International Nuclear Information System (INIS)

    Risch, P.; Ait Abderrahim, H.; D'hondt, P.; Malabu, E.

    1997-01-01

    An intercomparison of calculated fast neutron flux (E > 1 MeV) traverse through a very thick water zone obtained using both S N , (DORT) and Monte-Carlo (TRIPOLI and MCBEND) codes in combination with different cross-sections libraries (based on ENDF/B-III, IV, V and VI), showed small discrepancies either between S N , and Monte-Carlo results or even between S N , or Monte-Carlo results when we consider different cross-sections libraries except for S N , calculation when using P 0 , cross-sections. In order to validate our calculations we looked for experimental data. Unfortunately no experiment, dedicated for the fast neutron transport in large thickness of water, was found in the literature. Therefore SCK-CEN and EDF decided to launch the WINES experiment which is dedicated to study this phenomenon. WINES sands for Water Inelastic Neutron scattering Experimental Study. The aim of this experiment is to provide-experimental data for validation of neutron transport codes and nuclear cross-sections libraries used for LWR surveillance dosimetry analysis. The experimental device is made of 1 m 3 cubic plexiglass container filled with demineralized water. At one face of this cube, a 235 U neutron fission source system is screwed. The source device is made of a 235 U (93 % weight enriched) 18.55 x 16 cm 2 plate cladded with aluminium which is inserted in neutron beam emerging from the graphite gas-cooled BR1 reactor. Fission chambers ( 238 U(n,f), 232 Th(n,f), 237 Np(n,f) and 235 U(n,f)) are used to measure the flux traverses on the central axis of the water cube perpendicular to the fission sources. In this paper we will compare the experimental data to the calculated results using the S N , transport code DORT with the P 3 , ELXSIR library, based on ENDF/B-V, and the P 7 -BUGLE-93 library, based on ENDF/B-VI as well as the Monte-Carlo transport code TRIPOLI with a cross-section library based on ENDF/B IV and ENDF/B-VI. (authors)

  18. Experimental study of curved guide tubes for pellet injection

    International Nuclear Information System (INIS)

    Combs, S.K.; Baylor, L.R.; Foust, C.R.; Gouge, M.J.; Jernigan, T.C.; Milora, S.L.

    1997-01-01

    The use of curved guide tubes for transporting frozen hydrogen pellets offers great flexibility for pellet injection into plasma devices. While this technique has been previously employed, an increased interest in its applicability has been generated with the recent ASDEX Upgrade experimental data for magnetic high-field side (HFS) pellet injection. In these innovative experiments, the pellet penetration appeared to be significantly deeper than for the standard magnetic low-field side injection scheme, along with corresponding greater fueling efficiencies. Thus, some of the major experimental fusion devices are planning experiments with HFS pellet injection. Because of the complex geometries of experimental fusion devices, installations with multiple curved guide tube sections will be required for HFS pellet injection. To more thoroughly understand and document the capability of curved guide tubes, an experimental study is under way at the Oak Ridge National Laboratory (ORNL). In particular, configurations and pellet parameters applicable for the DIII-D tokamak and the International Thermonuclear Experimental Reactor (ITER) were simulated in laboratory experiments. Initial test results with nominal 2.7- and 10-mm-diam deuterium pellets are presented and discussed

  19. Experimental identification of a comb-shaped chaotic region in multiple parameter spaces simulated by the Hindmarsh—Rose neuron model

    Science.gov (United States)

    Jia, Bing

    2014-03-01

    A comb-shaped chaotic region has been simulated in multiple two-dimensional parameter spaces using the Hindmarsh—Rose (HR) neuron model in many recent studies, which can interpret almost all of the previously simulated bifurcation processes with chaos in neural firing patterns. In the present paper, a comb-shaped chaotic region in a two-dimensional parameter space was reproduced, which presented different processes of period-adding bifurcations with chaos with changing one parameter and fixed the other parameter at different levels. In the biological experiments, different period-adding bifurcation scenarios with chaos by decreasing the extra-cellular calcium concentration were observed from some neural pacemakers at different levels of extra-cellular 4-aminopyridine concentration and from other pacemakers at different levels of extra-cellular caesium concentration. By using the nonlinear time series analysis method, the deterministic dynamics of the experimental chaotic firings were investigated. The period-adding bifurcations with chaos observed in the experiments resembled those simulated in the comb-shaped chaotic region using the HR model. The experimental results show that period-adding bifurcations with chaos are preserved in different two-dimensional parameter spaces, which provides evidence of the existence of the comb-shaped chaotic region and a demonstration of the simulation results in different two-dimensional parameter spaces in the HR neuron model. The results also present relationships between different firing patterns in two-dimensional parameter spaces.

  20. Experimental identification of a comb-shaped chaotic region in multiple parameter spaces simulated by the Hindmarsh—Rose neuron model

    International Nuclear Information System (INIS)

    Jia Bing

    2014-01-01

    A comb-shaped chaotic region has been simulated in multiple two-dimensional parameter spaces using the Hindmarsh—Rose (HR) neuron model in many recent studies, which can interpret almost all of the previously simulated bifurcation processes with chaos in neural firing patterns. In the present paper, a comb-shaped chaotic region in a two-dimensional parameter space was reproduced, which presented different processes of period-adding bifurcations with chaos with changing one parameter and fixed the other parameter at different levels. In the biological experiments, different period-adding bifurcation scenarios with chaos by decreasing the extra-cellular calcium concentration were observed from some neural pacemakers at different levels of extra-cellular 4-aminopyridine concentration and from other pacemakers at different levels of extra-cellular caesium concentration. By using the nonlinear time series analysis method, the deterministic dynamics of the experimental chaotic firings were investigated. The period-adding bifurcations with chaos observed in the experiments resembled those simulated in the comb-shaped chaotic region using the HR model. The experimental results show that period-adding bifurcations with chaos are preserved in different two-dimensional parameter spaces, which provides evidence of the existence of the comb-shaped chaotic region and a demonstration of the simulation results in different two-dimensional parameter spaces in the HR neuron model. The results also present relationships between different firing patterns in two-dimensional parameter spaces

  1. Experimental study of radon and thoron diffusion through barriers

    Energy Technology Data Exchange (ETDEWEB)

    Durcik, M; Havlik, F [Inst. of Preventive and Clinical Medicine, 83301 Bratislava (Slovakia)

    1996-12-31

    The measurement results of diffusion parameters for radon (radon-222) and thoron (radon-220) through barriers, experimental equipment and theoretical background of diffusion are presented in this paper. The diffusion barriers are used for measuring radon and thoron by passive detectors in order to test the reduction techniques in houses. Six samples (filter paper, rubber, polyethylene, glass laminate, polypropylene) were studied for radon diffusion. The thickness barriers were from 0.012 mm to 2 mm, the diffusion area was 16 cm{sup 2} and the volume V{sub 2} was 30 dm{sup 3}. The diffusion constants D were obtained using given expressions and the data from measurements. The procedures used in experiments are useful for study of diffusion ability of radon and thoron in barriers and determination diffusion parameters from short term measurements. (J.K.). 2 figs., 1 tab., 3 refs.

  2. Experimental study of radon and thoron diffusion through barriers

    International Nuclear Information System (INIS)

    Durcik, M.; Havlik, F.

    1995-01-01

    The measurement results of diffusion parameters for radon (radon-222) and thoron (radon-220) through barriers, experimental equipment and theoretical background of diffusion are presented in this paper. The diffusion barriers are used for measuring radon and thoron by passive detectors in order to test the reduction techniques in houses. Six samples (filter paper, rubber, polyethylene, glass laminate, polypropylene) were studied for radon diffusion. The thickness barriers were from 0.012 mm to 2 mm, the diffusion area was 16 cm 2 and the volume V 2 was 30 dm 3 . The diffusion constants D were obtained using given expressions and the data from measurements. The procedures used in experiments are useful for study of diffusion ability of radon and thoron in barriers and determination diffusion parameters from short term measurements. (J.K.). 2 figs., 1 tab., 3 refs

  3. Correlation between muscle electrical impedance data and standard neurophysiologic parameters after experimental neurogenic injury

    International Nuclear Information System (INIS)

    Ahad, M; Rutkove, S B

    2010-01-01

    Previous work has shown that electrical impedance measurements of muscle can assist in quantifying the degree of muscle atrophy resulting from neuronal injury, with impedance values correlating strongly with standard clinical parameters. However, the relationship between such data and neurophysiologic measurements is unexplored. In this study, 24 Wistar rats underwent sciatic crush, with measurement of the 2–1000 kHz impedance spectrum, standard electrophysiological measures, including nerve conduction studies, needle electromyography, and motor unit number estimation (MUNE) before and after sciatic crush, with animals assessed weekly for 4 weeks post-injury. All electrical impedance values, including a group of 'collapsed' variables, in which the spectral characteristics were reduced to single values, showed reductions as high as 47.2% after sciatic crush, paralleling and correlating with changes in compound motor action potential amplitude, conduction velocity and most closely to MUNE, but not to the presence of fibrillation potentials observed on needle electromyography. These results support the concept that localized impedance measurements can serve as surrogate makers of nerve injury; these measurements may be especially useful in assessing nerve injury impacting proximal or axial muscles where standard quantitative neurophysiologic methods such as nerve conduction or MUNE cannot be readily performed

  4. Experimental Study of Dust Grain Charging

    Science.gov (United States)

    Spann, James F; Venturini, Catherine C.; Comfort, Richard H.; Mian, Abbas M.

    1999-01-01

    The results of an experimental study of the charging mechanisms of micron size dust grains are presented. Individual dust grains are electrodynamically suspended and exposed to an electron beam of known energy and flux, and to far ultraviolet radiation of known wavelength and intensity. Changes in the charge-to-mass ratio of the grain are directly measured as a function of incident beam (electron and/or photon), grain size and composition. Comparisons of our results to theoretical models that predict the grain response are presented.

  5. An experimental study of dislocation loop nucleation

    International Nuclear Information System (INIS)

    Bounaud, J.Y.; Leteurtre, J.

    1975-01-01

    The nucleation of dislocation loops is experimentally studied by observing the demixion of the Burgers vectors of dislocation loops nucleated in copper whiskers irradiated in flexion by fission fragments at room temperature. The demixion of Burgers vectors is observed by the dimensional effects of dislocation loops: after irradiation, the applied stress is removed; the whisker shows a residual strain that is due to loops because, after an annealing treatment to evaporate dislocation loops, each whisker recovers its initial straight shape. Everywhere along the whisker, the radius of curvature is measured and plotted vs the max. applied stress. Estimations of the interstitial and vacancy dislocation loop nuclei are derived [fr

  6. Clinical and experimental studies on radiation proctitis

    International Nuclear Information System (INIS)

    Honke, Yoshifumi

    1988-01-01

    Clinical and experimental studies were performed to clarify the mechanism of developing radiation proctitis. The results were as follows; (1) In the clinical study with 38 uterine cervix cancer patients, who received radiotherapy, diarrhea was observed in 44.7% at the acute stage, while rectal bleeding in 36.7% about 1 year after radiation. However, no clinical correlation was observed between diarrhea and rectal bleeding. (2) Colon fiberscopic examination revealed little change at the acute stage. However, erosion, ulcer and remarkable redness were found at the late stage. By the magnified fiberscope, unit degeneration was found in 72.8% at the acute stage. (3) Concerning the histopathological changes, edema and inflammatory change were observed immediately after irradiation. Fibrosis was observed in 83.3% at the late stage. (4) The number of the immunoglobulin containing cells decreased by radiation. However, its recovered as time passed after radiation. (5) In experimental study with rats by microangiography, there were ramarkable changes of the small vessels, such as bending, tortuosity and capillary hyperplasia at the acute stage. However, these changes returned to normal soon. At the late stage, decreased number of blood vessels were observed. The above results indicated that rectal bleeding after exposure to radiation are developed by secondary circulation abnormality caused by fibrosis of the perivascular tissues. (author) 52 refs

  7. Theoretical and experimental study of heat transfers and pressure drops along surfaces fitted with herring-bone fins: correlation between geometric and aero thermal parameters; Etudes theorique et experimentale du transfert de chaleur et des pertes de charge de surfaces munies d'ailettes disposees en chevron - correlation entre parametres geometriques et aerothermiques

    Energy Technology Data Exchange (ETDEWEB)

    Pelce, J; Malherbe, J; Pierre, B [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1965-07-01

    Principal results are given of experimental research which has been carried out on the flow of a fluid along a surface fitted with herringbone fins. Aero-thermal tests have been effected on a large number of these surfaces whose geometrical parameters have been made to vary systematically. In particular, work on a large scale model has made it possible to analyse the mechanisms of heat transfer and of pressure drops. On this basis a theoretical study has led to the establishment of a correlation between the geometric configuration and the aero-thermal performances of these surfaces. Experimental results are in good agreement with the theoretical relationships. An expression has thus been derived applicable to this type of herring-boned surface in a wide zone. (authors) [French] L'ecoulement d'un fluide au voisinage d'une surface munie d'ailettes disposees en chevron a fait l'objet de recherches experimentales dont on a rappele les principaux resultats. Des essais aerothermiques ont ete effectues sur un grand nombre de ces surfaces dont a fait varier les parametres geometriques de facon systematique. En particulier, des etudes sur une maquette a grande echelle ont permis d'analyser les mecanismes de transfert de chaleur et de perte de charge. Sur ces bases, une etude theorique a conduit a des correlations entre la geometrie et les performances aerothermiques de ces surfaces. Les resultats experimentaux sont en bon accord avec les relations theoriques. On possede ainsi une formulation pour ce type de surface ailettee valable dans un domaine etendu. (auteurs)

  8. Astrophysical parameters of ten poorly studied open star clusters

    International Nuclear Information System (INIS)

    Tadross, Ashraf Latif; El-Bendary, Reda; Osman, Anas; Ismail, Nader; Bakry, Abdel Aziz

    2012-01-01

    We present the fundamental parameters of ten open star clusters, nominated from Kronberger et al. who presented some newly discovered stellar groups on the basis of the Two Micron All Sky Survey photometry and Digitized Sky Survey visual images. Star counts and photometric parameters (radius, membership, distance, color excess, age, luminosity function, mass function, total mass, and dynamical relaxation time) have been determined for these ten clusters for the first time. In order to calibrate our procedures, the main parameters (distance, age, and color excess) have been re-estimated for another five clusters, which are also studied by Kronberger et al. (research papers)

  9. Experimental study of rf pulsed heating

    CERN Document Server

    Laurent, L; Nantista, C; Dolgashev, V; Higashi, Y; Aicheler, M; Tantawi, S; Wuensch, W

    2011-01-01

    Cyclic thermal stresses produced by rf pulsed heating can be the limiting factor on the attainable reliable gradients for room temperature linear accelerators. This is especially true for structures that have complicated features for wakefield damping. These limits could be pushed higher by using special types of copper, copper alloys, or other conducting metals in constructing partial or complete accelerator structures. Here we present an experimental study aimed at determining the potential of these materials for tolerating cyclic thermal fatigue due to rf magnetic fields. A special cavity that has no electric field on the surface was employed in these studies. The cavity shape concentrates the magnetic field on one flat surface where the test material is placed. The materials tested in this study have included oxygen free electronic grade copper, copper zirconium, copper chromium, hot isostatically pressed copper, single crystal copper, electroplated copper, Glidcop (R), copper silver, and silver plated co...

  10. Experimental and theoretical study of Co sorption in clay montmorillonites

    Science.gov (United States)

    Gil Rebaza, A. V.; Montes, M. L.; Taylor, M. A.; Errico, L. A.; Alonso, R. E.

    2018-03-01

    Montmorillonite (MMT) clays are 2:1 layered structures which in natural state may allocate different hydrated cations such as M-nH2O (M = Na, Ca, Fe, etc) in its interlayer space. Depending on the capability for ion sorption, these materials are interesting for environmental remediation. In this work we experimentally study the Co sorption in a natural Na-MMT using UV-visible spectrometry and XRD on semi-oriented samples, and then analyze the sorption ability of this clay by means of ab initio calculation performed on pristine MMT. The structural properties of Na-MMT and Co-adsorbed MMT, and the hyperfine parameters at different atomic sites were analyzed and compared with the experimental ones for the first, and for the case of the hyperfine parameters, presented for the first time for the last. The theoretical predictions based on total energy considerations confirm that Co incorporation replacing Na is energetically favorable. Also, the basal spacing d001 experimentally obtained is well reproduced.

  11. Experimental study of steam condensation regime map for simplified spargers

    International Nuclear Information System (INIS)

    Kim, Y. S.; Yoon, Y. J.; Song, C. H.; Park, C. K.; Kang, H. S.; Jun, H. K.

    2003-01-01

    An experimental study was conducted to produce a condensation regime map for single-hole and 4-hole steam spargers using GIRLS facility. The regime map for a single-hole sparger was derived using parameters such as the frequency and magnitude of the dynamic pressure. For 4-hole sparager, the regime map was derived using the trends of sound and dynamic pressure. Using the single-hole and 4-hole data, a steam jet condensation regime map was suggested with respect to pool temperature and steam mass flux

  12. Laparoscopic ureterocalicostomy in pigs - experimental study

    Directory of Open Access Journals (Sweden)

    Paulo Fernando de Oliveira Caldas

    2015-07-01

    Full Text Available This study aimed to evaluated laparoscopic ureterocalicostomy as treatment of experimental ureteropelvic junction (UPJ obstruction in pigs. Ten male Large White pigs weighting approximately 28.4 (±1.43 kg were used in the current study. The UPJ obstruction was created laparoscopically by double-clipping of the left ureter. After 14 days the animals underwent laparoscopic ureterocalicostomy f The animals were sacrificed for subsequent retrograde pyelography in order to assess the anastomotic patency on the 28th day. The laparoscopic procedure for experimental obstruction of UPJ was successfully performed in all animals, as well as the laparoscopic ureterocalicostomy. There was intestinal iatrogenic injury in one animal. Satisfactory UPJ patency was noted in 75% of the animals. There was no stenosis of the proximal anastomosis between the ureter and the lower pole of the kidney in 37.5%, mild stenosis in 37.5% and severe stenosis in 25% of the animals. The laparoscopic approach for reestablishment he urinary flow by ureterocalicostomy was feasible in the porcine model. The ascending pyelography revealed satisfactory results of the laparoscopic ureterocalicostomy

  13. Experimental study of unsteady thermally stratified flow

    International Nuclear Information System (INIS)

    Lee, Sang Jun; Chung, Myung Kyoon

    1985-01-01

    Unsteady thermally stratified flow caused by two-dimensional surface discharge of warm water into a oblong channel was investigated. Experimental study was focused on the rapidly developing thermal diffusion at small Richardson number. The basic objectives were to study the interfacial mixing between a flowing layer of warm water and an underlying body of cold water and to accumulate experimental data to test computational turbulence models. Mean velocity field measurements were carried out by using NMR-CT(Nuclear Magnetic Resonance-Computerized Tomography). It detects quantitative flow image of any desired section in any direction of flow in short time. Results show that at small Richardson number warm layer rapidly penetrates into the cold layer because of strong turbulent mixing and instability between the two layers. It is found that the transfer of heat across the interface is more vigorous than that of momentum. It is also proved that the NMR-CT technique is a very valuable tool to measure unsteady three dimensional flow field. (Author)

  14. Vascularized nerve grafts: an experimental study.

    Science.gov (United States)

    Donzelli, Renato; Capone, Crescenzo; Sgulò, Francesco Giovanni; Mariniello, Giuseppe; Maiuri, Francesco

    2016-08-01

    The aim of this study is to define an experimental model in order to promote the functional recovery of the nerves using grafts with vascular support (Vascular Nerve Grafts - VNG). The aim of this study is to define, on an experimental model in normal recipient bed, whether the functional recovery with VNG is superior to that obtained non-vascularized graft (NNG). Twenty male rabbits, which underwent dissection of sciatic nerve, were later treated by reinnervation through an autograft. In 10 animals the reconstruction of sciatic nerve was realized with VNG; in 10 control animals the reconstruction of sciatic nerve was realized with NNG. The VNG group showed a better axonal organization and a significantly higher number of regenerated axons in the early phases (after 30 days) than the NNG group, whereas the difference in the axonal number at day 90 was less significant; besides, the axon diameter and the myelin thickness were not significantly improved by VNG group. Our data suggests that the use of VNG leads to a faster regeneration process and a better functional recovery, although the final results are comparable to those of the NNG. VNG improve the quality of the axonal regeneration (axonal diameter and Schwann cells), although the increase in the axonal number is not significant and does not improve the long-term functional outcome.

  15. Study on Identification of Material Model Parameters from Compact Tension Test on Concrete Specimens

    Science.gov (United States)

    Hokes, Filip; Kral, Petr; Husek, Martin; Kala, Jiri

    2017-10-01

    Identification of a concrete material model parameters using optimization is based on a calculation of a difference between experimentally measured and numerically obtained data. Measure of the difference can be formulated via root mean squared error that is often used for determination of accuracy of a mathematical model in the field of meteorology or demography. The quality of the identified parameters is, however, determined not only by right choice of an objective function but also by the source experimental data. One of the possible way is to use load-displacement curves from three-point bending tests that were performed on concrete specimens. This option shows the significance of modulus of elasticity, tensile strength and specific fracture energy. Another possible option is to use experimental data from compact tension test. It is clear that the response in the second type of test is also dependent on the above mentioned material parameters. The question is whether the parameters identified within three-point bending test and within compact tension test will reach the same values. The presented article brings the numerical study of inverse identification of material model parameters from experimental data measured during compact tension tests. The article also presents utilization of the modified sensitivity analysis that calculates the sensitivity of the material model parameters for different parts of loading curve. The main goal of the article is to describe the process of inverse identification of parameters for plasticity-based material model of concrete and prepare data for future comparison with identified values of the material model parameters from different type of fracture tests.

  16. Ethanol Production from Kitchen Garbage Using Zymomonas mobilis: Optimization of Parameters through Statistical Experimental Designs

    OpenAIRE

    Ma, H.; Wang, Q.; Gong, L.; Wang, X.; Yin, W.

    2008-01-01

    Plackett-Burman design was employed to screen 8 parameters for ethanol production from kitchen garbage by Zymomonas mobilis in simultaneous saccharification and fermentation. The parameters were divided into two parts, four kinds of enzymes and supplementation nutrients. The result indicated that the nutrient inside kitchen garbage could meet the requirement of ethanol production without supplementation, only protease and glucoamylase were needed to accelerate the ethanol production. The opti...

  17. Delivery parameters, neonatal parameters and incidence of urinary incontinence six months postpartum: a cohort study.

    Science.gov (United States)

    Wesnes, Stian Langeland; Hannestad, Yngvild; Rortveit, Guri

    2017-10-01

    Contradictory results have been reported regarding most delivery parameters as risk factors for urinary incontinence. We investigated the association between the incidence of urinary incontinence six months postpartum and single obstetric risk factors as well as combinations of risk factors. This study was based on the Norwegian Mother and Child Cohort Study, conducted by the Norwegian Institute of Public Health during 1998-2008. This substudy was based on 7561 primiparous women who were continent before and during pregnancy. Data were obtained from questionnaires answered at weeks 15 and 30 of pregnancy and six months postpartum. Data were linked to the Medical Birth Registry of Norway. Single and combined delivery- and neonatal parameters were analyzed by logistic regression analyses. Birthweight was associated with significantly higher risk of urinary incontinence six months postpartum [3541-4180 g: odds ratio (OR) 1.4, 95% confidence interval (CI) 1.2-1.6; >4180 g: OR 1.6, 95% CI 1.2-2.0]. Fetal presentation, obstetric anal sphincter injuries, episiotomy and epidural analgesia were not significantly associated with increased risk of urinary incontinence. The following combinations of risk factors among women delivering by spontaneous vaginal delivery increased the risk of urinary incontinence six months postpartum; birthweight ≥3540 g and ≥36 cm head circumference; birthweight ≥3540 g and forceps, birthweight ≥3540 g and episiotomy; and ≥36 cm head circumference and episiotomy. Some combinations of delivery parameters and neonatal parameters seem to act together and may increase the risk of incidence of urinary incontinence six months postpartum in a synergetic way. © 2017 Nordic Federation of Societies of Obstetrics and Gynecology.

  18. Spillover effects in epidemiology: parameters, study designs and methodological considerations

    Science.gov (United States)

    Benjamin-Chung, Jade; Arnold, Benjamin F; Berger, David; Luby, Stephen P; Miguel, Edward; Colford Jr, John M; Hubbard, Alan E

    2018-01-01

    Abstract Many public health interventions provide benefits that extend beyond their direct recipients and impact people in close physical or social proximity who did not directly receive the intervention themselves. A classic example of this phenomenon is the herd protection provided by many vaccines. If these ‘spillover effects’ (i.e. ‘herd effects’) are present in the same direction as the effects on the intended recipients, studies that only estimate direct effects on recipients will likely underestimate the full public health benefits of the intervention. Causal inference assumptions for spillover parameters have been articulated in the vaccine literature, but many studies measuring spillovers of other types of public health interventions have not drawn upon that literature. In conjunction with a systematic review we conducted of spillovers of public health interventions delivered in low- and middle-income countries, we classified the most widely used spillover parameters reported in the empirical literature into a standard notation. General classes of spillover parameters include: cluster-level spillovers; spillovers conditional on treatment or outcome density, distance or the number of treated social network links; and vaccine efficacy parameters related to spillovers. We draw on high quality empirical examples to illustrate each of these parameters. We describe study designs to estimate spillovers and assumptions required to make causal inferences about spillovers. We aim to advance and encourage methods for spillover estimation and reporting by standardizing spillover parameter nomenclature and articulating the causal inference assumptions required to estimate spillovers. PMID:29106568

  19. Experimental Research and Mathematical Modeling of Parameters Effecting on Cutting Force and SurfaceRoughness in CNC Turning Process

    Science.gov (United States)

    Zeqiri, F.; Alkan, M.; Kaya, B.; Toros, S.

    2018-01-01

    In this paper, the effects of cutting parameters on cutting forces and surface roughness based on Taguchi experimental design method are determined. Taguchi L9 orthogonal array is used to investigate the effects of machining parameters. Optimal cutting conditions are determined using the signal/noise (S/N) ratio which is calculated by average surface roughness and cutting force. Using results of analysis, effects of parameters on both average surface roughness and cutting forces are calculated on Minitab 17 using ANOVA method. The material that was investigated is Inconel 625 steel for two cases with heat treatment and without heat treatment. The predicted and calculated values with measurement are very close to each other. Confirmation test of results showed that the Taguchi method was very successful in the optimization of machining parameters for maximum surface roughness and cutting forces in the CNC turning process.

  20. Experimental study of hydronic panels system and its environment

    Energy Technology Data Exchange (ETDEWEB)

    Diaz, Nestor Fonseca [University of Liege Belgium, Thermodynamics Laboratory, Campus du Sart Tilman, Bat: B49 - P33, B-4000 Liege (Belgium); Universidad Tecnologica de Pereira, Facultad de Ingenieria Mecanica (Colombia)

    2011-01-15

    An experimental analysis of hydronic cooling or heating ceiling panels coupled to the building is present in this investigation as a part of the commissioning study of this system. Two test chambers are adapted in a way to reproduce the interaction of the system to the building (windows, internal thermal loads distribution, building structure and ventilation). A series of experimental tests were performed in which the main objective is to observe the influence of parameters such as the water mass flow rate, supply water temperature, thermal load distribution, window and ventilation system effects on the hydronic ceiling capacity and comfort conditions. Test results show that the influence of asymmetric surfaces temperatures inside the room, especially the window effect is not negligible. Then, it is clear that the cooling hydronic ceiling must be evaluated coupled to the building systems and structure. (author)

  1. Experimental study of hydronic panels system and its environment

    Energy Technology Data Exchange (ETDEWEB)

    Fonseca Diaz, Nestor, E-mail: nestorfonseca5@hotmail.co [University of Liege Belgium, Thermodynamics Laboratory, Campus du Sart Tilman, Bat: B49 - P33, B-4000 Liege (Belgium); Universidad Tecnologica de Pereira, Facultad de Ingenieria Mecanica (Colombia)

    2011-01-15

    An experimental analysis of hydronic cooling or heating ceiling panels coupled to the building is present in this investigation as a part of the commissioning study of this system. Two test chambers are adapted in a way to reproduce the interaction of the system to the building (windows, internal thermal loads distribution, building structure and ventilation). A series of experimental tests were performed in which the main objective is to observe the influence of parameters such as the water mass flow rate, supply water temperature, thermal load distribution, window and ventilation system effects on the hydronic ceiling capacity and comfort conditions. Test results show that the influence of asymmetric surfaces temperatures inside the room, especially the window effect is not negligible. Then, it is clear that the cooling hydronic ceiling must be evaluated coupled to the building systems and structure.

  2. Experimental study on external condensation heat transfer characteristics of bellows

    International Nuclear Information System (INIS)

    Feng Dianyi; Hu Jiansheng

    2008-01-01

    Flow model and heat transfer of condensation flow outside of bellows have been theoretically and experimentally studied. The formula for calculation of condensation heat transfer coefficient was deduced, and corrected through experiment. The calculation results are accordant with the experimental ones, and the errors is less than 10%. The effect of bellows structure parameters and pipe diameter on the enhancement heat transfer has been investigated. It is found that in the steady flow region, the average condensation heat transfer coefficient in a bellows is 3 ∼ 5 times than that in a straight tube under the same conditions, and when considering the increasing in heat transfer area, the effectiveness of enhancement heat transfer is 5 ∼ 7 times than that in a straight tube. To facilitate the engineering design and application of bellows, the formula for the calculation of the average heat transfer coefficient of a fluid in a bellows was also given. (authors)

  3. Granular Silo collapse: an experimental study

    Science.gov (United States)

    Clement, Eric; Gutierriez, Gustavo; Boltenhagen, Philippe; Lanuza, Jose

    2008-03-01

    We present an experimental work that develop some basic insight into the pre-buckling behavior and the buckling transition toward plastic collapse of a granular silo. We study different patterns of deformation generated on thin paper cylindrical shells during granular discharge. We study the collapse threshold for different bed height, flow rates and grain sizes. We compare the patterns that appear during the discharge of spherical beads, with those obtained in the axially compressed cylindrical shells. When the height of the granular column is close to the collapse threshold, we describe a ladder like pattern that rises around the cylinder surface in a spiral path of diamond shaped localizations, and develops into a plastic collapsing fold that grows around the collapsing silo.

  4. Microwave generation for magnetic fusion energy applications: Task A -- Experimental and numerical study of microwave sources for ECRH incorporating depressed collectors and with ITER-relevant parameters, and Task B -- Theory and modeling of high frequency, high power gyrotron operation. Final report, July 15, 1994--July 14, 1995

    International Nuclear Information System (INIS)

    1995-01-01

    A proof-of-principle short pulse (∼ 100 ns) experiment has successfully demonstrated operation of a sheet-beam FEL amplifier with output power of 250 kW at 86 Ghz and with 24 dB saturated gain and ∼ 3% efficiency. Gain in the linear region was 30 dB. Measured performance parameters were in good agreement with predictions of a multi-mode, time dependence code. Also, a code has been developed to design depressed collectors which will enhance efficiency of ECRH sources (both FELs and gyrotrons). Extensive analytical and theoretical work in support of high power gyrotron development at Varian and MIT, and in support of ITER has been carried out. Specific studies are described. The effect of beam quality on the operation of the 145 GHz gyrotrons at MIT has been characterized using experimentally measured beam velocity distribution functions. The observed performance of these devices is consistent with a 10% RMS perpendicular velocity spread. An extensive study of mode competition in the 110 GHZ experiments at Varian and MIT has been carried out. Design criteria for the suppression of parasitic modes have been given for these experiments. The issues of mode competition and beam quality in the proposed 170 GHz megawatt gyrotrons for ITER have been investigated. Designs of cavities which eliminate unwanted modes have been made, and their sensitivity to beam quality studied. The constraints of lower power density and absence of mode competition coupled with the anticipated beam quality restrict efficiency. Efficiency can be improved by increasing the power density in the wall, improving beam quality, or perhaps by using a more advanced cavity. Studies of the causes of velocity spread in MIG guns have been initiated. Further, the effect of beam cavity misalignment on mode competition has been addressed

  5. Experimental study on low pressure flow instability

    International Nuclear Information System (INIS)

    Jiang Shengyao; Wu Xinxin; Wu Shaorong; Bo Jinhai; Zhang Youjie

    1997-05-01

    The experiment was performed on the test loop (HRTL-5), which simulates the geometry and system design of the 5 MW reactor. The flow behavior for a wide range of inlet subcooling, in which the flow undergoes from single phase to two phase, is described in a natural circulation system at low pressure (p = 0.1, 0.24 MPa). Several kinds of flow instability, e.g. subcooled boiling instability, subcooled boiling induced flashing instability, pure flashing instability as well as flashing coupled density wave instability and high frequency flow oscillation, are investigated. The mechanism of flashing and flashing concerned flow instability, which has never been studied well in this field, is especially interpreted. The experimental results show that, firstly, for a low pressure natural circulation system the two phase flow is unstable in most of inlet subcooling conditions, the two phase stable flow can only be reached at very low inlet subcooling; secondly, at high inlet subcooling the flow instability is dominated by subcooled boiling in the heated section, and at middle inlet subcooling is dominated by void flashing in the adiabatic long riser; thirdly, in two phase stable flow region the condition for boiling out of the core, namely, single phase flow in the heated section, two phase flow in the riser due to vapor flashing, can be realized. The experimental results are very important for the design and accident analysis of the vessel and swimming pool type natural circulation nuclear heating reactor. (7 refs., 10 figs., 1 tab.)

  6. Metabolic Desynchronization in Critical Conditions: Experimental Study

    Directory of Open Access Journals (Sweden)

    G. V. Livanov

    2006-01-01

    Full Text Available Objective. To conduct an experimental study of the impact of the time of administration of succinic acid preparations on central nervous system (CNS function and gas exchange while simulating metabolic therapy for severe poisoning by ethyl alcohol. The study was performed on 74 male albino rats weighing 140—180 g. Acute severe and very severe intoxication was simulated, by intraabdominally administering 30% ethanol to the rats. Cytoflavin was used to simulate experimental therapy. The rate of gas exchange was estimated by the oxygen uptake determined by the closed chamber method in a Regnault apparatus (Germany. Spontaneous bioelectrical activity was recorded in the frontooccipital lead by the routine procedure. External pain stimulation and rhythmical photostimulation were employed to evaluate cerebral responsiveness. Heterodirectional EEG changes in the «early» and «late» administration of succinate were not followed by the similar alterations of gas exchange: oxygen consumption in both the «early» and «late» administration of succinate remained significantly lower than in the control animals. With the late administration of succinate to the animals with mixed (toxic and hypoxic coma, the so-called discrepancy between the noticeably increased energy production and brutally diminished metabolism occurred. It may be just the pathological mechanism that was the basis for higher mortality in the late succinate administration group. The findings and their analysis make it possible to advance a hypothesis that succinate may cause metabolic desynchronization if activation of metabolic processes takes place under severe tissue respiratory tissue depression. In these cases, there is a severe damage to tissue and chiefly the brain. This manifests itself as EEG epileptiform activity splashes preceding the animals’ death. Therefore, resuscitation aimed at restoring the transport of oxygen and its involvement in tissue energy processes should

  7. Reactor parameters for European economic, safety and environmental studies

    International Nuclear Information System (INIS)

    Hancox, R.; Cooke, P.I.H.; Spears, W.R.

    1990-01-01

    Parameter sets for five 1200 MW e tokamak reactors were developed for the European Study Group on the Environmental, Safety-related and Economic Potential of Fusion Power, showing today's perception of the range of reactors likely to be available as a result of the Commission's fusion programme. On the basis of the cost of generating electricity, relative to a fission reactor, a reference set was chosen and endorsed by the Group for further studies including that on the environmental impact of fusion power. Key physics and technology parameters for the reference reactor are compared with values used in the ITER design, and with those from American studies. (author)

  8. Experimental design approach to the process parameter optimization for laser welding of martensitic stainless steels in a constrained overlap configuration

    Science.gov (United States)

    Khan, M. M. A.; Romoli, L.; Fiaschi, M.; Dini, G.; Sarri, F.

    2011-02-01

    This paper presents an experimental design approach to process parameter optimization for the laser welding of martensitic AISI 416 and AISI 440FSe stainless steels in a constrained overlap configuration in which outer shell was 0.55 mm thick. To determine the optimal laser-welding parameters, a set of mathematical models were developed relating welding parameters to each of the weld characteristics. These were validated both statistically and experimentally. The quality criteria set for the weld to determine optimal parameters were the minimization of weld width and the maximization of weld penetration depth, resistance length and shearing force. Laser power and welding speed in the range 855-930 W and 4.50-4.65 m/min, respectively, with a fiber diameter of 300 μm were identified as the optimal set of process parameters. However, the laser power and welding speed can be reduced to 800-840 W and increased to 4.75-5.37 m/min, respectively, to obtain stronger and better welds.

  9. The combined theoretical and experimental approach to arrive at optimum parameters in friction stir welding

    Science.gov (United States)

    Jagadeesha, C. B.

    2017-12-01

    Even though friction stir welding was invented long back (1991) by TWI England, till now there has no method or procedure or approach developed, which helps to obtain quickly optimum or exact parameters yielding good or sound weld. An approach has developed in which an equation has been derived, by which approximate rpm can be obtained and by setting range of rpm ±100 or 50 rpm over approximate rpm and by setting welding speed equal to 60 mm/min or 50 mm/min one can conduct FSW experiment to reach optimum parameters; one can reach quickly to optimum parameters, i.e. desired rpm, and welding speed, which yield sound weld by the approach. This approach can be effectively used to obtain sound welds for all similar and dissimilar combinations of materials such as Steel, Al, Mg, Ti, etc.

  10. Mortar alteration: experimental study and ancient analogues

    International Nuclear Information System (INIS)

    Rassineux, Francois

    1987-01-01

    As the durability of cemented matrices is a matter of great importance in numerous domains, notably for the long term reliability of surface storages of radioactive wastes, the objective of this research thesis is to define mechanisms of evolution of cemented matrices when in contact with diluted aqueous solutions. The author notably studied the influence of the lixiviation mode on the evolution of two mortars having different compositions (pH, CO 2 pressure, system containment, and cement mineralogical nature appear to be the main governing parameters), the alteration (dissolution is the prevailing process in the interaction between cemented matrices and a diluted solution such as rain water), and ancient binders (archaeological binders containing mineral phases such as hydrated calcium silicates or hydro-grossulars). The obtained results lead to the definition of alteration mechanisms in modern cements, and highlight factors governing the durability of these materials when submitted to meteoric alteration [fr

  11. Contribution to the experimental study of the hydraulic jump in ...

    African Journals Online (AJOL)

    The purpose of this study is to study experimentally the hydraulic jump evolving in a symmetric trapezoidal channel with a positive slope, requires the use of an experimental protocol, and to find experimental relations linking the characteristics of the formed projection. The experimental study investigated the variation of the ...

  12. Study on the Energetic Parameters in a Photothermic Sensor with ...

    African Journals Online (AJOL)

    Study on the Energetic Parameters in a Photothermic Sensor with Black Polymeric Film. ... The evolution of incidental solar illumination on the horizontal plan of sensor and the temperature distribution are studied. Results showed that the ... Keywords: film, solar energy, greenhouse effect, design, radiation, illumination.

  13. Pulmonary emphysema induced by methylphenidate: experimental study.

    Science.gov (United States)

    Rapello, Gabriel Victor Guimarães; Antoniolli, Andréia; Pereira, Daniel Martins; Facco, Gilberto; Pêgo-Fernandes, Paulo Manuel; Pazetti, Rogério

    2015-01-01

    Methylphenidate is the most widely used drug for treating attention deficit hyperactivity disorder. However, it has important side effects, such as abdominal pain, insomnia, anorexia and loss of appetite, and also some cases of early severe emphysema after drug abuse have been reported. Our aim was to investigate the development of pulmonary emphysema in rats that were subjected to different doses of methylphenidate. Experimental study carried out at the laboratory of a public university. Eighteen male Wistar rats were divided into three groups: control (0.9% saline solution); MP 0.8 (methylphenidate, 0.8 mg/kg); MP 1.2 (methylphenidate, 1.2 mg/kg). After 90 days of daily gavage, the animals were sacrificed and lung tissue samples were prepared for analysis on the mean alveolar diameter (Lm). The Lm was greater in MP 0.8 (47.91 ± 3.13; P pulmonary emphysema.

  14. Experimental Study of Factors Affecting Soil Erodibility

    Science.gov (United States)

    Larionov, G. A.; Bushueva, O. G.; Gorobets, A. V.; Dobrovolskaya, N. G.; Kiryukhina, Z. P.; Krasnov, S. F.; Litvin, L. F.; Maksimova, I. A.; Sudnitsyn, I. I.

    2018-03-01

    The effect of different factors and preparation conditions of monofraction samples from the arable horizon of leached chernozem on soil erodibility and its relationship with soil tensile strength (STS) has been studied. The exposure of samples at 38°C reduces their erodibility by two orders of magnitude. The drying of samples, on the contrary, increases their erodibility. It has been shown that erodibility decreases during the experiment. It has been found that the inoculation of soil with yeast cultures ( Naganishia albida, Lipomyces tetrasporus) reliably increases the STS value in 1.5-1.9 times. The sterile soil is eroded more intensively than the unsterile soil: at 4.9 and 0.3 g/(m2 s), respectively. The drying of soil followed by wetting to the initial water content (30%) has no significant effect on the STS value in almost all experimental treatments.

  15. Experimental study of crossing angle collision

    International Nuclear Information System (INIS)

    Chen, T.; Rice, D.; Rubin, D.; Sagan, D.; Tigner, M.

    1993-01-01

    The non-linear coupling due to the beam-beam interaction with crossing angle has been studied. The major effect of a small (∼12mrad) crossing angle is to excite 5Q x ±Q s =integer coupling resonance family on large amplitude particles, which results in bad lifetime. On the CESR, a small crossing angle (∼2.4mr) was created at the IP and a reasonable beam-beam tune-shift was achieved. The decay rate of the beam is measured as a function of horizontal tune with and without crossing angle. The theoretical analysis, simulation and experimental measurements have a good agreement. The resonance strength as a function of crossing angle is also measured

  16. Experimental and theoretical study of reflux condensation

    Energy Technology Data Exchange (ETDEWEB)

    Bakke, Knut

    1997-12-31

    This thesis studies the separation of gas mixtures in a reflux condenser. also called a dephlegmator. Reflux condensation is separation of a gas mixture, in reflux flow with condensing liquid, under continuous heat removal. A numerical model of a dephlegmator for binary mixtures was developed. The model may readily be extended to multi-component mixtures, as the solution method is based on a matrix solver. Separation of a binary mixture in a reflux condenser test rig is demonstrated. The test facility contains a single-tube test section that was designed and built as part of the project. Test mixtures of propane and n-butane were used, and a total of 15 experiments are reported. Limited degree of separation was achieved due to limited heat transfer area and narrow boiling point range of the test mixture. The numerical model reproduces the experimental data within reasonable accuracy. Deviation between calculated and measured properties is less than 6% of the measured temperature and less than 5% of the measured flow rate. The model is based on mechanistic models of physical processes and is not calibrated or tuned to fit the experimental data. The numerical model is applied to a number of separation processes. These case studies show that the required heat transfer area increases rapidly with increments in top product composition (light component). Flooding limits the amount of reflux liquid. The dephlegmator is suitable for separation of feed mixtures that are rich in light components. The gliding temperature in the dephlegmation process enables utilization of top product as refrigerant, with subsequent energy saving as a result. 61 refs., 50 figs., 34 tabs.

  17. An experimental study of mixed convection

    International Nuclear Information System (INIS)

    Saez, Manuel

    1998-01-01

    The aim of our study is to establish a reliable data base for improving thermal-hydraulic codes, in the field of turbulent flows with buoyancy forces. The flow considered is mixed convection in the Reynolds and Richardson number range: Re=10"3 to 6*10"4 and Ri=10"-"4 to 1. Experiments are carried out in an upward turbulent flow between vertical parallel plates at different wall temperatures. Part 1 gives a detailed data base of turbulent mixed flow of free and forced convection. Part II presents the installation and the calibration system intended for probes calibration. Part III describes the measurement technique (constant-temperature probe and cold-wire probe) and the method for measuring the position of the hot-wire anemometer from the wall surface. The measurement accuracy is within 0.001 mm in the present system. Part IV relates the development of a method for near wall measurements. This correction procedure for hot-wire anemometer close to wall has been derived on the basis of a two-dimensional numerical study. The method permits to obtain a quantitative correction of the wall influence on hot-wires and takes into account the velocity profile and the effects the wall material has on the heat loss. Part V presents the experimental data obtained in the channel in forced and mixed convection. Results obtained in the forced convection regime serve as a verification of the measurement technique close to the wall and give the conditions at the entrance of the test section. The effects of the buoyancy force on the mean velocity and temperature profiles are confirmed. The buoyancy strongly affects the flow structure and deforms the distribution of mean velocity. The velocity profiles are asymmetric. The second section of part V gives an approach of analytical wall functions with buoyancy forces, on the basis of the experimental data obtained in the test section. (author) [fr

  18. A numerical study of non-linear crack tip parameters

    Directory of Open Access Journals (Sweden)

    F.V. Antunes

    2015-07-01

    Full Text Available Crack closure concept has been widely used to explain different issues of fatigue crack propagation. However, different authors have questioned the relevance of crack closure and have proposed alternative concepts. The main objective here is to check the effectiveness of crack closure concept by linking the contact of crack flanks with non-linear crack tip parameters. Accordingly, 3D-FE numerical models with and without contact were developed for a wide range of loading scenarios and the crack tip parameters usually linked to fatigue crack growth, namely range of cyclic plastic strain, crack tip opening displacement, size of reversed plastic zone and total plastic dissipation per cycle, were investigated. It was demonstrated that: i LEFM concepts are applicable to the problem under study; ii the crack closure phenomenon has a great influence on crack tip parameters decreasing their values; iii the Keff concept is able to explain the variations of crack tip parameters produced by the contact of crack flanks; iv the analysis of remote compliance is the best numerical parameter to quantify the crack opening level; v without contact there is no effect of stress ratio on crack tip parameters. Therefore it is proved that the crack closure concept is valid.

  19. Experimental Study of Flow Through Carotid Aneurysms

    Science.gov (United States)

    Masoomi, Faezeh; Mejia-Alvarez, Ricardo

    2017-11-01

    There is evidence that traditional endovascular techniques like coiling are not effective for treatment of wide-neck cerebral aneurysms. Flow Diverter Stents (FDS) have emerged as promising devices for treating complex aneurysms since they enable treatment of aneurysms that were considered untreatable before. Recent studies suggest a number of associated risks with FDS, including in-stent thrombosis, perianeurysmal edema, delayed hemorrhage, and perforator occlusions. Chong et al. simulated hemodynamic behavior using patient-specific data. From their study, it is possible to infer that the standard deviation of energy loss could be a good predictor for intervention success. The aim of this study is to investigate the flow in models of cerebral aneurysms before and after FDS insertion using PIV. These models will be based on actual clinical studies and will be fabricated with advanced additive manufacturing techniques. These data will then be used to explore flow parameters that could inform the likelihood of post-intervention aneurysm rupture, and help determine FDS designs that better suit any particular patient before its procedure.

  20. Experimentally-based optimization of contact parameters in dynamics simulation of humanoid robots

    NARCIS (Netherlands)

    Vivian, Michele; Reggiani, Monica; Sartori, Massimo

    2013-01-01

    With this work we introduce a novel methodology for the simulation of walking of a humanoid robot. Motion capture technology is used to calibrate the dynamics engine internal parameters and validate the simulated motor task. Results showed the calibrated contact model allows predicting dynamically

  1. Determination of the physical parameters distribution in spin transition compounds using experimental FORC diagram

    International Nuclear Information System (INIS)

    Tanasa, Radu; Linares, Jorge; Enachescu, Cristian; Varret, Francois; Stancu, Alexandru

    2006-01-01

    Spin transitions materials are characterized with an innovative experimental method, i.e. first-order reversal curve (FORC) diagram. The interpretation of the results is performed in the framework of two different Ising-like models: a mean-field approach and the exact solution done by the Monte Carlo entropic sampling (MCES) method

  2. Construction of an experimental simplified model for determining of flow parameters in chemical reactors, using nuclear techniques

    International Nuclear Information System (INIS)

    Araujo Paiva, J.A. de.

    1981-03-01

    The development of a simplified experimental model for investigation of nuclear techniques to determine the solid phase parameters in gas-solid flows is presented. A method for the measurement of the solid phase residence time inside a chemical reactor of the type utilised in the cracking process of catalytic fluids is described. An appropriate radioactive labelling technique of the solid phase and the construction of an eletronic timing circuit were the principal stages in the definition of measurement technique. (Author) [pt

  3. Experimental design for parameter estimation of two time-scale model of photosynthesis and photoinhibition in microalgae

    Czech Academy of Sciences Publication Activity Database

    Papáček, Š.; Čelikovský, Sergej; Rehák, Branislav; Štys, D.

    2010-01-01

    Roč. 80, č. 6 (2010), s. 1302-1309 ISSN 0378-4754 R&D Projects: GA ČR(CZ) GA102/08/0186 Institutional research plan: CEZ:AV0Z10750506 Keywords : Photosynthetic factory * Experimental design * Parameter estimation * Two-scale modeling Subject RIV: BC - Control Systems Theory Impact factor: 0.812, year: 2010 http://library.utia.cas.cz/separaty/2010/TR/celikovsky-0341543.pdf

  4. Experimental study of rf pulsed heating

    Directory of Open Access Journals (Sweden)

    Lisa Laurent

    2011-04-01

    Full Text Available Cyclic thermal stresses produced by rf pulsed heating can be the limiting factor on the attainable reliable gradients for room temperature linear accelerators. This is especially true for structures that have complicated features for wakefield damping. These limits could be pushed higher by using special types of copper, copper alloys, or other conducting metals in constructing partial or complete accelerator structures. Here we present an experimental study aimed at determining the potential of these materials for tolerating cyclic thermal fatigue due to rf magnetic fields. A special cavity that has no electric field on the surface was employed in these studies. The cavity shape concentrates the magnetic field on one flat surface where the test material is placed. The materials tested in this study have included oxygen free electronic grade copper, copper zirconium, copper chromium, hot isostatically pressed copper, single crystal copper, electroplated copper, Glidcop®, copper silver, and silver plated copper. The samples were exposed to different machining and heat treatment processes prior to rf processing. Each sample was tested to a peak pulsed heating temperature of approximately 110°C and remained at this temperature for approximately 10×10^{6} rf pulses. In general, the results showed the possibility of pushing the gradient limits due to pulsed heating fatigue by the use of copper zirconium and copper chromium alloys.

  5. Theoretical and experimental studies of elementary physics

    International Nuclear Information System (INIS)

    Bodek, A.; Ferbel, T.; Melissinos, A.C.; Slattery, P.; Tipton, P.; Das, A.; Hagen, C.R.; Rajeev, S.G.; Okubo, S.; Orr, L.

    1993-01-01

    The various components of the high-energy physics research program at the University of Rochester are presented. (I)Fixed-target experimentation at FNAL includes studies of direct photon production by p and π on H, Be, and Cu, and hybrid mesons and other physics issues in Coulomb excitation at high energies. (II)The status of the GEM (Gammas, Electrons, and Muons) Experiment at the SSC is given. (III)The D-Zero experiment at FNAL is reviewed. (IV)Deep inelastic lepton--nucleon scattering experiments are summarized: electron scattering experiments at SLAC, FNAL neutrino quad triplet runs, FNAL neutrino sign selected experiments, and SDC cosmic ray test and test beam calibration. (V)Studies of nonlinear QED at SLAC concentrated on a study of QED at critical field strength in intense laser--high-energy electron collisions. (VI)Development work on the Collider Detector at Fermilab (CDF) emphasized the CDF silicon vertex detector, the end plug calorimeter, and the SDC tile/fiber calorimetry. (VII)The theoretical physics effort is sketched

  6. PRELIMINARY STUDY OF HEMATOLOGICAL PARAMETERS IN HERZEGOVINIAN DONKEY

    Directory of Open Access Journals (Sweden)

    Dunja Rukavina

    2016-02-01

    Full Text Available Herzegovinian donkey is a very important animal resource of Bosnia and Herzegovina. There have been no works attempted at determining the normal values of hematological parameters of Herzegovinian donkey. For this reason, the objective of the present study was to investigate some hematological parameters in Herzegovinian donkey. The research was performed on 30 apparently healthy donkeys (18 female and 12 male of ages from 1 to 20 years. Blood samples (3 ml were obtained by jugular vein puncture (vena jugularis externa in vacuum tubes with EDTA. The mean value of hematocrit was 29.19 %, hemoglobin concentration 10.6 g/dl, mean corpuscular hemoglobin concentration 36.33 g/dl, white blood cells 9.33 x109/L, granulocytes (109/L 5.45 x109/L, granulocytes (% 59.47%, lymphocyte/monocyte (109/L 3.89 x109/L, lymphocyte/monocyte (% 40.53% and platelet cells 148.97 x109/L. Parameters were determined using an automated analyzer IDEXX QBC VET AutoRead. Data were analyzed by SPSS V 15. All hematological parameters (except platelet cells were consistent with the recommended reference ranges for donkeys, and the values found in literature so far. Platelet cells values were much lower than in the literature for the other donkey breeds and the recommended reference ranges for donkeys. The slight differences found between our results and those reported in the previous works confirm the need for further studies to investigate the reference values of hematological parameters of Herzegovinian donkey. This work is a contribution to the study of hematological parameters of Herzegovinian donkey, and we expect these data to be applied to the further studies.

  7. Experimental investigation on local parameter measurement using optical probes in two-phase flow under rolling condition

    International Nuclear Information System (INIS)

    Tian Daogui; Sun Licheng; Yan Changqi; Liu Guoqiang

    2013-01-01

    In order to get more local interfacial information as well as to further comprehend the intrinsic mechanism of two-phase flow under rolling condition, a method was proposed to measure the local parameters by using optical probes under rolling condition in this paper. An experimental investigation of two-phase flow under rolling condition was conducted using the probe fabricated by the authors. It is verified that the probe method is feasible to measure the local parameters in two'-phase flow under rolling condition. The results show that the interfacial parameters distribution near wall region has a distinct periodicity due to the rolling motion. The averaged deviation of the void fraction measured by the probe from that obtained from measured pressure drop is about 8%. (authors)

  8. Experimental determination of the dimensionless scaling parameter of energy transport in tokamaks

    International Nuclear Information System (INIS)

    Luce, T.C.; Petty, C.C.

    1995-07-01

    Controlled fusion experiments have focused on the variation of the plasma characteristics as the engineering or control parameters are systematically changed. This has led to the development of extrapolation formulae for prediction of future device performance using these same variables as a basis. Recently, it was noticed that present-day tokamaks can operate with all of the dimensionless variables which appear in the Vlasov-Maxwell system of equations at values projected for a fusion powerplant with the exception of the parameter ρ * , the gyroradius normalized to the machine size. The scaling with this parameter is related to the benefit of increasing the size of the machine either directly or effectively by increasing the magnetic field. It is exactly this scaling which is subject to systematic error in the inter-machine databases and the cost driver for any future machine. If this scaling can be fixed by a series of single machine experiments, much as the current and power scalings have been, the confidence in the prediction of future device performance would be greatly enhanced. While carrying out experiments of this type, it was also found that the ρ * scaling can illuminate the underlying physics of energy transport. Conclusions drawn from experiments on the DIII-D tokamak in these two areas are the subject of this paper

  9. Studies of Some Parameters Affecting The Efficiency and Accuracy of The Neutron Activation Analysis Technique

    International Nuclear Information System (INIS)

    Abdel-Haleem, A.S.; Zaghloul, R.A.; Sroor, A.; Abdel Sabour, M.F.

    2000-01-01

    The present studies deal with the optimum physical conditions which seriously affect the neutron activation analysis technique efficiency. An experimental work for the efficiency calibration of hyper pure germanium detectors especially for environmental studies is presented. This work showed that the tested parameters, under consideration, distance, mass and measured time, reveal a significant effect on the obtained data. These results, intern, affect the accuracy of the measurements. Further work on the test of other parameters is planned in our laboratory using special treatments and applying special computer programs

  10. The normative study of acoustic parameters in normal Egyptian ...

    African Journals Online (AJOL)

    Yehia A. Abo-Ras

    2013-03-21

    Mar 21, 2013 ... all children were subjected to computerized acoustic analysis using Multidimensional voice program ... cal quality is important for social relations to happen effectively. ... lish comparative parameters with the normal values of the acoustic ... from lower age ranges in the normative studies since the child's.

  11. Developing the Parameters of Scholarship in Postgraduate Coursework Studies

    Science.gov (United States)

    McLay, Allan F.

    2013-01-01

    Scholarship parameters, in relation to postgraduate coursework studies, are developed against the expectations of the Boyer classifications of scholarship (Boyer, 1990) with particular emphasis on the role of minor thesis development. An example is presented in which postgraduate coursework students are required to undertake a three semester minor…

  12. An experimental study on the characteristics of electromagnetic filter

    International Nuclear Information System (INIS)

    Lee, Geum Yong; Lim, Seung Cheol; Lee, Kun Jai

    1993-01-01

    The electromagnetic filter has been recognized as a technological replacement for the conventional filtration systems of the nuclear power plant coolant. But, as of now there are neither clear understandings of the phenomena occurring in the electromagnetic filter nor the general theoretical analyses. These facts make the application of the electromagnetic filter to the real systems a little risky, and therfore it has not been commercialized although it shows excellent performances in such situations as the plant abnormality, where the conventional filters usually fail. This experimental study of the low power electromagnetic filter aims at the clarification of the general characteristics under varying operational parameters. Since the detailed characteristics may differ from one electromagnetic filter to another, they are considered secondary. The impurities applied are the highly magnetic magnetite (Fe 3 O 4 ) and the diamagnetic cuprous oxide (Cu 2 O). The empirical equations are derived from the experimental data by the regressional analyses. They are classified of three types : Efficiencies vs. Time, Efficiencies vs. Load, and Load vs. Time. The characteristics of the electromagnetic filter observed in this experiment agreed well with other related works in many aspects. Especially in this study, some assumptions and discussions including the physical deposition are combined for the explanations of the filter characteristics found in our and other experimental works. (Author)

  13. Parameters of importance to determine in geoscientific site studies

    International Nuclear Information System (INIS)

    Andersson, Johan; Almen, K.E.; Ericsson, L.O.; Karlsson, Fred; Stroem, A.; Fredriksson, Anders; Stanfors, R.

    1996-12-01

    This report identifies and describes parameters, that may be determined in a site characterization study, for performing functional and safety analyses of a deep rock repository for radioactive wastes. The report discusses data needs for rock engineering and for description of other environmental aspects. It is intended that the report be used as a basis for formulating the criteria of acceptance in evaluating a candidate site. The report describes how different parameters influence the safety function, and how they are evaluated in practice. The logical order of performing measurements, due to the need of in-data and influence on other measurements is also discussed. 65 refs

  14. Experimental Study on Critical Power in a Hemispherical Narrow Gap

    International Nuclear Information System (INIS)

    Park, Rae-Joon; Ha, Kwang-Soon; Kim, Sang-Baik; Kim, Hee-Dong; Jeong, Ji-Hwan

    2002-01-01

    An experimental study of critical heat flux in gap (CHFG) has been performed to investigate the inherent cooling mechanism in a hemispherical narrow gap. The objectives of the CHFG test are to measure critical power from a critical heat removal rate through the hemispherical narrow gap using distilled water with experimental parameters of system pressure and gap width. The CHFG test results have shown that a countercurrent flow limitation (CCFL) brings about local dryout at the small edge region of the upper part and finally global dryout in a hemispherical narrow gap. Increases in the gap width and pressure lead to an increase in critical power. The measured values of critical power are lower than the predictions made by other empirical CHF correlations applicable to flat plate, annuli, and small spherical gaps. The measured data on critical power in the hemispherical narrow gaps have been correlated using nondimensional parameters with a range of approximately ±20%. The developed correlation has been expanded to apply the spherical geometry using the Siemens/KWU correlation

  15. Laboratory testing of waste glass aqueous corrosion; effects of experimental parameters

    International Nuclear Information System (INIS)

    Ebert, W.L.; Mazer, J.J.

    1993-01-01

    A literature survey has been performed to assess the effects of the temperature, glass surface area/leachate volume ratio, leachant composition, leachant flow rate, and glass composition (actual radioactive vs. simulated glass) used in laboratory tests on the measured glass reaction rate. The effects of these parameters must be accounted for in mechanistic models used to project glass durability over long times. Test parameters can also be utilized to highlight particular processes in laboratory tests. Waste glass corrosion results as water diffusion, ion-exchange, and hydrolysis reactions occur simultaneously to devitrify the glass and release soluble glass components into solution. The rates of these processes are interrelated by the affects of the solution chemistry and glass alteration phases on each process, and the dominant (fastest) process may change as the reaction progresses. Transport of components from the release sites into solution may also affect the observed corrosion rate. The reaction temperature will affect the rate of each process, while other parameters will affect the solution chemistry and which processes are observed during the test. The early stages of corrosion will be observed under test conditions which maintain dilute leachates and the later stages will be observed under conditions that generate more concentrated leachate solutions. Typically, water diffusion and ion-exchange reactions dominate the observed glass corrosion in dilute solutions while hydrolysis reactions dominant in more concentrated solutions. Which process(es) controls the long-term glass corrosion is not fully understood, and the long-term corrosion rate may be either transport- or reaction-limited

  16. Experimental Measures of Bus Comfort Levels Using Kinematic Parameters Recorded by Smartphone

    Energy Technology Data Exchange (ETDEWEB)

    Aquila, S. dell' ; Eboli, L.; Futia, G.; Mazzulla, G.; Pungillo, G.

    2016-07-01

    Comfort on board plays an essential role in the levels of satisfaction of a bus service perceived by passengers. The aim of this paper is to propose a measure of comfort based on two kinds of data: perceptions of passengers (subjective data) and accelerations of bus (objective data). For the collection of subjective data a questionnaire was addressed to a sample of university students, while a smartphone, equipped with GPS device and 3-axis accelerometer, was used to record the accelerations. Based on the recorded parameters, we determined the thresholds of the acceleration values beyond which the level of comfort cannot be considered as good.. (Author)

  17. Experimental thermochemical study of two chlorodinitroaniline isomers

    International Nuclear Information System (INIS)

    Ribeiro da Silva, Manuel A.V.; Ribeiro da Silva, Maria D.M.C.; Santos, Ana Filipa L.O.M.; Ferreira, Ana I.M.C. Lobo; Galvao, Tiago L.P.

    2010-01-01

    The standard (p 0 =0.1MPa) molar enthalpies of formation of 2-chloro-4,6-dinitroaniline and 4-chloro-2,6-dinitroaniline, in the gaseous phase, at T = 298.15 K, were derived from the combination of the values of the standard molar enthalpies of formation, in the crystalline phase, and of the standard molar enthalpies of sublimation, at the same temperature. The standard molar enthalpies of formation, in the crystalline phase, were derived from the standard massic energies of combustion, in oxygen, measured by rotating-bomb combustion calorimetry. The standard molar enthalpies of sublimation were calculated, by the application of the Clausius-Clapeyron equation, to the vapour pressures at several temperatures, measured by Knudsen effusion technique. The values of the standard molar enthalpies of formation of 2-chloro-4,6-dinitroaniline and 4-chloro-2,6-dinitroaniline, in the gaseous phase, at T = 298.15 K, are discussed in terms of enthalpic increments, and the enthalpy of isomerization between the two compounds is compared with the same parameter for two isomers of chloronitroaniline, studied in previous works.

  18. Experimental Studies of Electrothermal Plasma Gun

    International Nuclear Information System (INIS)

    Diab, F.B.A.

    2013-01-01

    The aim of the present work is to study the capillary plasma discharge dynamics and characteristics. The capillary plasma device is a new technology for producing high density plasma after ablating the capillary wall using a pulsed electric power. An Electrothermal Plasma Gun (ETG) is composed of a capillary discharge tube made of Teflon operated with simple RLC circuit. The device called Electrothermal Gun (ETG) which is composed of 4 capacitors (70 μF, 10 kV, 1.28 μH) connected in parallel to a plasma source by means of one high power supply. The gun was operated in open air at discharge energies between 35 J - 3.5 kJ according to charging voltage. The work presented in this thesis covers the following items, 1- Measurements of the basic parameters and characterizations of the pretest results of the electrical circuits and capillary plasma discharge using Rogowski coil, voltage probe and Photomultiplier. 2- Material processing including (physics of the surface modifications, the morphology of the surface by using Scanning Electron Microscope (SEM) at different conditions, compositions of the materials by using X-ray Fluorescence (XRF), Micro hardness test and material particle deposition.

  19. Using numerical simulations to extract parameters of toroidal electron plasmas from experimental data

    DEFF Research Database (Denmark)

    Ha, B. N.; Stoneking,, M. R.; Marler, Joan

    2009-01-01

    Measurements of the image charge induced on electrodes provide the primary means of diagnosing plasmas in the Lawrence Non-neutral Torus II (LNT II) [Phys. Rev. Lett. 100, 155001 (2008)]. Therefore, it is necessary to develop techniques that determine characteristics of the electron plasma from......, as in the cylindrical case. In the toroidal case, additional information about the m=1 motion of the plasma can be obtained by analysis of the image charge signal amplitude and shape. Finally, results from the numerical simulations are compared to experimental data from the LNT II and plasma characteristics...

  20. Experimental study of chaos synchronization in the Belousov-Zhabotinsky chemical system

    International Nuclear Information System (INIS)

    Li Yanni; Chen Lan; Cai Zunsheng; Zhao Xuezhuang

    2004-01-01

    Employing self-adaptive parameter regulation scheme, chaos synchronization in the Belousov-Zhabotinsky-CSTR chemical system has been studied experimentally. By optimizing the combination of regulation parameters, the trend of chaos synchronization is observed and the prediction of chaos synchronization from numerical simulation is thus verified by the experiment. In addition, the difference of sensitivity to noise with the mass coupling scheme and the self-adaptive parameter regulation scheme in chaos synchronization has also been discussed

  1. Experimental study of finite Larmor radius effects

    International Nuclear Information System (INIS)

    Struve, K.W.

    1980-08-01

    Linear Z-pinches in Ar, Kr, Xe, N 2 , and He are experimentally studied in regimes where strong finite Larmor radius effects could provide a significant stabilizing effect. Scaling arguments show that for deuterium such a pinch has an electron line density of order 2 x 10 15 /cm. For higher Z plasmas a higher line density is allowed, the exact value of which depends on the average ion charge. The pinch is formed by puffing gas axially through the cathode towards the anode of an evacuated pinch chamber. When the gas reaches the anode, the pinch bank is fired. The pinch current rises in 2 to 3 μsec to a maximum of 100 to 200 kA. The pinch bank capacitance is 900 μF, and the external inductance is 100 nH. Additionally, the bank is fused to increase dI/dt. The primary diagnostics are a framing camera, a spatially resolved Mach-Zehnder interferometer, and X-ray absorption

  2. Experimental Study on Revetec Engine Cam Performance

    International Nuclear Information System (INIS)

    Gasim, Maisara Mohyeldin; Chui, Lee Giok; Anwar, Khirul Azhar bin

    2012-01-01

    In Revetec engine (three-lobed) cam replaces the crankshaft to convert the reciprocating motion of the engine piston, to a rotating motion in the drive line. Since the cam controls the piston movement, the cam profile has a great effect on engine performance. In this paper an experimental study was done to a (three- lobed) cam with Cycloidal motion profile but with different ratios between the base circle radius of the cam and the radius of the roller follower. DEWESoft was used to find the displacement and the vibration of the piston, and compare the actual results from the test with the theoretical results from the cam profile equation. The results showed that there is a periods of miss contact between the follower and the cam when the ratio between the base circle radius of the cam and the radius of the roller follower is less than a certain value, and also increasing of vibration. The suggested ratio between the cam and follower radius is to be more than 2:1.

  3. Experimental study of vapor bubble dynamics

    International Nuclear Information System (INIS)

    Pasquini, Maria-Elena

    2015-01-01

    The object of this thesis is an experimental study of vapor bubble dynamics in sub-cooled nucleate boiling. The test section is locally heated by focusing a laser beam: heat fluxes from 1 e4 to 1.5 e6 W/m 2 and water temperature between 100 and 88 C have been considered. Three boiling regimes have been observed. Under saturated conditions and with low heat fluxes a developed nucleate boiling regime has been observed. Under higher sub-cooling and still with low heat fluxes an equilibrium regime has been observed in which the liquid flowrate evaporating at the bubble base is compensated by the vapor condensing flowrate at bubble top. A third regime have been observed at high heat fluxes for all water conditions: it is characterized by the formation of a large dry spot on the heated surface that keeps the nucleation site dry after bubble detachment. The condensation phase starts after bubble detachment. Bubble equivalent radius at detachment varies between 1 and 2.5 mm. Bubble properties have been measured and non-dimensional groups have been used to characterize bubble dynamics. Capillary waves have been observed on the bubble surface thanks to high-speed images acquisition. Two main phenomena have been proposed to explain capillary waves effects on bubble condensation: increasing of the phases interface area and decreasing of vapor bubble translation velocity, because of the increased drag force on the deformed bubble. (author) [fr

  4. Experimental studies of fiber concrete creep

    Directory of Open Access Journals (Sweden)

    Korneeva Irina

    2017-01-01

    Full Text Available The results of two-stage experimental studies of the strength and deformation characteristics of fibrous concrete reinforced with steel fiber. In the experiments we used steel fiber with bent ends, which practically does not form "hedgehogs", which allows to achieve an even distribution of the fiber by volume. At the first stage, the cube and prismatic strength, deformability at central compression, a number of special characteristics are determined: water absorption, frost resistance, abrasion; the optimal percentage of fiber reinforcement and the maximum size of the coarse aggregate fraction were selected. Fiber reinforcement led to an increase in the strength of concrete at compression by 1,35 times and an increase in the tensile strength at bending by 3,4 times. At the second stage, the creep of fibrous concrete and plain concrete of similar composition at different stress levels was researched. Creep curves are plotted. It is shown that the use of fiber reinforcement leads to a decrease in creep strain by 21 to 30 percent, depending on the stress level.

  5. Experimental study of a spark-gap

    International Nuclear Information System (INIS)

    Bruzzone, H.; Moreno, C.; Vieytes, R.

    1990-01-01

    Some experimental results concerning to the resistance of an atmospheric pressure spark-gap, operating in the self breakdown regime are presented. The influence of the energy discharging through the gap on this resistance is discussed. (Author)

  6. Evapotranspiration studies for protective barriers: Experimental plans

    International Nuclear Information System (INIS)

    Link, S.O.; Waugh, W.J.

    1989-11-01

    This document describes a general theory and experimental plans for predicting evapotranspiration in support of the Protective Barrier Program. Evapotranspiration is the combined loss of water from plants and soil surfaces to the atmosphere. 45 refs., 1 fig., 4 tabs

  7. Experimental Analyses of the Major Parameters Affecting the Intensity of Outbursts of Coal and Gas

    Science.gov (United States)

    Nie, W.; Peng, S. J.; Xu, J.; Liu, L. R.; Wang, G.; Geng, J. B.

    2014-01-01

    With an increase in mining depth and production, the intensity and frequency of outburst of coal and gas have a tendency to increase. Estimating the intensity of outbursts of coal and gas plays an important role because of its relation with the risk value. In this paper, we described the semiquantitative relations between major parameters and intensity of outburst based on physical experiments. The results showed increment of geostress simulated by horizontal load (from 1.4, 2.4, 3.2, to 3.4 MPa) or vertical load (from 2, 3, 3.6, to 4 MPa) improved the relative intensity rate (3.763–7.403% and 1.273–7.99%); the increment of porosity (from 1.57, 2.51, 3, to 3.6%) improved the relative intensity rate from 3.8 to 13.8%; the increment of gas pressure (from 0, 0.5, 0.65, 0.72, 1, to 1.5 Mpa) induced the relative intensity rate to decrease from 38.22 to 0%; the increment of water content (from 0, 2, 4, to 8%) caused the relative intensity rate to drop from 5.425 to 0.5%. Furthermore, sensitivity and range analysis evaluates coupled factors affecting the relative intensity. In addition, the distinction with initiation of outburst of coal and gas affected by these parameters is discussed by the relative threshold of gas content rate. PMID:25162042

  8. Experimental verification of internal parameter in magnetically coupled boost used as PV optimizer in parallel association

    Science.gov (United States)

    Sawicki, Jean-Paul; Saint-Eve, Frédéric; Petit, Pierre; Aillerie, Michel

    2017-02-01

    This paper presents results of experiments aimed to verify a formula able to compute duty cycle in the case of pulse width modulation control for a DC-DC converter designed and realized in laboratory. This converter, called Magnetically Coupled Boost (MCB) is sized to step up only one photovoltaic module voltage to supply directly grid inverters. Duty cycle formula will be checked in a first time by identifying internal parameter, auto-transformer ratio, and in a second time by checking stability of operating point on the side of photovoltaic module. Thinking on nature of generator source and load connected to converter leads to imagine additional experiments to decide if auto-transformer ratio parameter could be used with fixed value or on the contrary with adaptive value. Effects of load variations on converter behavior or impact of possible shading on photovoltaic module are also mentioned, with aim to design robust control laws, in the case of parallel association, designed to compensate unwanted effects due to output voltage coupling.

  9. TRIP-ID: A tool for a smart and interactive identification of Magic Formula tyre model parameters from experimental data acquired on track or test rig

    Science.gov (United States)

    Farroni, Flavio; Lamberti, Raffaele; Mancinelli, Nicolò; Timpone, Francesco

    2018-03-01

    Tyres play a key role in ground vehicles' dynamics because they are responsible for traction, braking and cornering. A proper tyre-road interaction model is essential for a useful and reliable vehicle dynamics model. In the last two decades Pacejka's Magic Formula (MF) has become a standard in simulation field. This paper presents a Tool, called TRIP-ID (Tyre Road Interaction Parameters IDentification), developed to characterize and to identify with a high grade of accuracy and reliability MF micro-parameters from experimental data deriving from telemetry or from test rig. The tool guides interactively the user through the identification process on the basis of strong diagnostic considerations about the experimental data made evident by the tool itself. A motorsport application of the tool is shown as a case study.

  10. Monte Carlo parameter studies and uncertainty analyses with MCNP5

    International Nuclear Information System (INIS)

    Brown, F. B.; Sweezy, J. E.; Hayes, R.

    2004-01-01

    A software tool called mcnp p study has been developed to automate the setup, execution, and collection of results from a series of MCNP5 Monte Carlo calculations. This tool provides a convenient means of performing parameter studies, total uncertainty analyses, parallel job execution on clusters, stochastic geometry modeling, and other types of calculations where a series of MCNP5 jobs must be performed with varying problem input specifications. (authors)

  11. Study of pipe-whip parameters in pipelines

    International Nuclear Information System (INIS)

    Guerreiro, J.N.C.; Loula, A.F.D.; Galeao, A.C.N.R.

    1980-01-01

    The problem of the high energy pipe-whip, assuming an elastic-plastic behavior for the tube material and taking in account the internal pressure, is studied. The constraints are simulated as bilinear springs and viscous dampers. A general research, based on the finite element method was developed to analyse the phenomenon. The influence of the following parameters: gap, damping coefficient, stiffness, constraints positioning and internal pressure of the tube is studied. (Author) [pt

  12. Experimental study of the pile EL3

    International Nuclear Information System (INIS)

    1958-01-01

    The results of two months' experiments, carried out at low power following the first divergence (4. July 1957) are presented. These experiments dealt with the following points: comparison of experimental and calculated values of the critical size; effects due to the introduction of absorbing materials into the principal experimental facilities, flux distribution measurements especially in these facilities, calibration of safety, control and compensating rods, determination of the average life of the neutrons. (author) [fr

  13. Strategy of experimental studies in PNC on natural convection decay heat removal

    International Nuclear Information System (INIS)

    Ieda, Y.; Kamide, H.; Ohshima, H.; Sugawara, S.; Ninokata, H.

    1993-01-01

    Experimental studies have been and are being carried out in PNC to establish the design and safety evaluation methods and the design and safety evaluation guide lines for decay heat removal by natural convection. A strategy of the experimental studies in PNC is described in this paper. The sphere of studies in PNC is to develop the evaluation methods to be available to DRACS as well as PRACS and IRACS for the plant where decay heat is removed by natural convection in some cases of loss of station service power. Similarity parameters related to natural convection are derived from the governing equations. The roles of both sodium and water experiments are defined in consideration of the importance of the similarity parameters and characteristics of scale model experiments. The experimental studies in PNC are reviewed. On the basis of the experimental results, recommended evaluation methods are shown for decay heat removal feature by natural convection. Future experimental works are also proposed. (author)

  14. Experimental Study of Lunar and SNC Magmas

    Science.gov (United States)

    Rutherford, Malcolm J.

    1998-01-01

    The research described in this progress report involved the study of petrological, geochemical and volcanic processes that occur on the Moon and the SNC parent body, generally accepted to be Mars. The link between these studies is that they focus on two terrestrial-type parent bodies somewhat smaller than earth, and the fact that they focus on the role of volatiles in magmatic processes and on processes of magma evolution on these planets. The work on the lunar volcanic glasses has resulted in some exciting new discoveries over the years of this grant. We discovered small metal blebs initially in the Al5 green glass, and determined the significant importance of this metal in fixing the oxidation state of the parent magma (Fogel and Rutherford, 1995). More recently, we discovered a variety of metal blebs in the Al7 orange glass. Some of these Fe-Ni metal blebs were in the glass; others were in olivine phenocrysts. The importance of these metal spheres is that they fix the oxidation state of the parent magma during the eruption, and also indicate changes during the eruption (Weitz et al., 1997) They also yield important information about the composition of the gas phase present, the gas which drove the lunar fire-fountaining. One of the more exciting and controversial findings in our research over the past year has been the possible fractionation of H from D during shock (experimental) of hornblende bearing samples (Minitti et al., 1997). This research is directed at explaining some of the low H2O and high D/H observed in hydrous phases in the SNC meteorites.

  15. Experimental and computational studies of nanofluids

    Science.gov (United States)

    Vajjha, Ravikanth S.

    The goals of this dissertation were (i) to experimentally investigate the fluid dynamic and heat transfer performance of nanofluids in a circular tube, (ii) to study the influence of temperature and particle volumetric concentration of nanofluids on thermophysical properties, heat transfer and pumping power, (iii) to measure the rheological properties of various nanofluids and (iv) to investigate using a computational fluid dynamic (CFD) technique the performance of nanofluids in the flat tube of a radiator. Nanofluids are a new class of fluids prepared by dispersing nanoparticles with average sizes of less than 100 nm in traditional heat transfer fluids such as water, oil, ethylene glycol and propylene glycol. In cold regions of the world, the choice of base fluid for heat transfer applications is an ethylene glycol or propylene glycol mixed with water in different proportions. In the present research, a 60% ethylene glycol (EG) or propylene glycol (PG) and 40% water (W) by mass fluid mixture (60:40 EG/W or 60:40 PG/W) was used as a base fluid, which provides freeze protection to a very low level of temperature. Experiments were conducted to measure the convective heat transfer coefficient and pressure loss of nanofluids flowing in a circular tube in the fully developed turbulent regime. The experimental measurements were carried out for aluminum oxide (Al2O3), copper oxide (CuO) and silicon dioxide (SiO2) nanoparticles dispersed in 60:40 EG/W base fluid. Experiments revealed that the heat transfer coefficient of nanofluids showed an increase with the particle volumetric concentration. Pressure loss was also observed to increase with the nanoparticle volumetric concentration. New correlations for the Nusselt number and the friction factor were developed. The effects of temperature and particle volumetric concentration on different thermophysical properties (e.g. viscosity, thermal conductivity, specific heat and density) and subsequently on the Prandtl number

  16. Experimental studies of renal blood flow by digitized functional angiography

    International Nuclear Information System (INIS)

    Buersch, J.H.; Ochs, C.; Hahne, H.J.; Heintzen, P.H.

    1985-01-01

    New techniques of digital image processing have been experimentally tested for the assessment of renal blood flow. The underlying principle in functional angiography is the extraction of flow parameters. Basically, density-time variations of the contrast medium are analayzed from to each picture element of a 256x256 matrix. The real-time acquisition rate of images was 25/sec. For the calculation of angiographic flow a PDP 11/40 computer was used to interactively perform a time dependent segmentation of the renal arteries and the aorta. Subsequently, volume flow was calculated in relative units for the specific vascular segments under study. 15 control angiograms were made in 5 animals with cardiac output ranging between 0.8 to 2.2l/min. Unilateral renal blood flow was calculated as 24+-3.4% of pre-renal aortic flow without systematic side differences. Reproducibility from repeated flow measurements showed an SD of +-1.8% of the individual pre-renal aortic flow. Renal flow was also measured in 3 animals with an experimentally created 50% flow reduction of the left kidney. Angiographic flow in the left renal artery dropped to 12+-2% of pre-renal flow. The present experimental data suggest that digital angiography has sufficient diagnostic capabilities for the detection of abnormal renal blood flow. The technique may serve as a useful diagnostic adjunct to conventional angiography and has the potential of assisting in the evaluation of renal vascular hypertension. (orig.) [de

  17. Experimental study of self-leveling behavior in debris bed

    International Nuclear Information System (INIS)

    Zhang, Bin; Harada, Tetsushi; Hirahara, Daisuke; Matsumoto, Tatsuya; Morita, Koji; Fukuda, Kenji; Yamano, Hidemasa; Suzuki, Tohru; Tobita, Yoshiharu

    2008-01-01

    After a core disruptive accident in a sodium-cooled fast reactor, core debris may settle on locations such as within the core-support structure or in the lower inlet plenum of the reactor vessel as debris beds, as a consequence of rapid quenching and fragmentation of core materials in subcooled sodium. The particle beds that are initially of varying depth have been observed to undergo a process of self-leveling when sodium boiling occurs within the beds. The boiling is believed to provide the driven force with debris needed to overcome resisting forces. Self-leveling ability has much effect on heat-removal capability of debris beds. In the present study, characteristics of self-leveling behaviors were investigated experimentally with simulant materials. Although the decay heat from fuel debris drives the coolant boiling in reactor accident conditions, the present experiments employed depressurization boiling of water to simulate axially increasing void distribution in a debris bed, which consists of solid particles of alumina or lead with different density. The particle size (from 0.5 mm to 6 mm in diameter) and shape (spherical or non-spherical particles) were also taken as experimental parameters. A rough criteria for self-leveling occurrence is proposed and compared with the experimental results. Characteristics of the self-leveling behaviors observed are analyzed and extrapolate to reactor accident conditions. (author)

  18. Stability of nanofluids: Molecular dynamic approach and experimental study

    International Nuclear Information System (INIS)

    Farzaneh, H.; Behzadmehr, A.; Yaghoubi, M.; Samimi, A.; Sarvari, S.M.H.

    2016-01-01

    Highlights: • Nanofluid stability is investigated and discussed. • A molecular dynamic approach, considering different forces on the nanoparticles, is adopted. • Stability diagrams are presented for different thermo-fluid conditions. • An experimental investigation is carried out to confirm the theoretical approach. - Abstract: Nanofluids as volumetric absorbent in solar energy conversion devices or as working fluid in different heat exchangers have been proposed by various researchers. However, dispersion stability of nanofluids is an important issue that must be well addressed before any industrial applications. Conditions such as severe temperature gradient, high temperature of heat transfer fluid, nanoparticle mean diameters and types of nanoparticles and base fluid are among the most effective parameters on the stability of nanofluid. A molecular dynamic approach, considering kinetic energy of nanoparticles and DLVO potential energy between nanoparticles, is adopted to study the nanofluid stability for different nanofluids at different working conditions. Different forces such as Brownian, thermophoresis, drag and DLVO are considered to introduce the stability diagrams. The latter presents the conditions for which a nanofluid can be stable. In addition an experimental investigation is carried out to find a stable nanofluid and to show the validity of the theoretical approach. There is a good agreement between the experimental and theoretical results that confirms the validity of our theoretical approach.

  19. Blood culture as a parameter of treatment effectiveness in experimental histoplasmosis of the hamster Hemocultivos como parametro de la eficacia del tratamiento de la histoplasmosis experimental en hamster

    Directory of Open Access Journals (Sweden)

    J. Finquelievich

    1995-04-01

    Full Text Available The aim of this study was to determine the value of blood culture as a parameter of treatment effectiveness in experimental histoplasmosis. A total of thirty five hamsters, weighing approximately 120g, were inoculated intracardiacly with 0.1 ml of a suspension containing 4 x 10(7 cells/ml of the yeast phase of H. capsulatum. Treatments were started one week after the infection and lasted for 3 weeks. The azoles, (itraconazole, saperconazole and fluconazole were administered once a day by gavage, at a dose of 8 mg/kg; Amphotericin B was given intraperitonealy every other day at a dose of 6mg/kg. Blood samples (1 ml were obtained by heart punction from the 4th day after infection and were seeded in Sabouraud honey-agar and BHI-agar. The hamsters that survived were killed one week after treatment completion and the following criteria were considered for treatment evaluation: 1 rate of spontaneous death, at the end of the experience; 2 microscopic examination of Giemsa smears from liver and spleen and 3 determination of CFU in spleen cultures. Amphotericin B was the most effective drug, with negative blood cultures at day 20, negative spleen cultures in all cases and all the animals survived until the end of the study. Fluconazole was the less effective drug, blood cultures were positive during the whole experience, spleen cultures showed a similar average of CFU when compared with the control animals and 42.8% of these animals died. Saperconazole and itraconazole showed a similar activity, with survival of all hamsters and negative blood cultures at 23 and 26 days respectively. Blood culture seems to be valuable parameter for treatments' evaluation in experimental histoplasmosis of the hamster.El propósito de esta investigación fue determinar el valor de los hemocultivos para juzgar la eficacia de los tratamientos en la histoplasmosis experimental. Treinta y cinco hamsters fueron inoculados por via intracardíaca con 0.1 ml de una suspensión de

  20. An Experimental Seismic Data and Parameter Exchange System for Tsunami Warning Systems

    Science.gov (United States)

    Hoffmann, T. L.; Hanka, W.; Saul, J.; Weber, B.; Becker, J.; Heinloo, A.; Hoffmann, M.

    2009-12-01

    For several years GFZ Potsdam is operating a global earthquake monitoring system. Since the beginning of 2008, this system is also used as an experimental seismic background data center for two different regional Tsunami Warning Systems (TWS), the IOTWS (Indian Ocean) and the interim NEAMTWS (NE Atlantic and Mediterranean). The SeisComP3 (SC3) software, developed within the GITEWS (German Indian Ocean Tsunami Early Warning System) project, capable to acquire, archive and process real-time data feeds, was extended for export and import of individual processing results within the two clusters of connected SC3 systems. Therefore not only real-time waveform data are routed to the attached warning centers through GFZ but also processing results. While the current experimental NEAMTWS cluster consists of SC3 systems in six designated national warning centers in Europe, the IOTWS cluster presently includes seven centers, with another three likely to join in 2009/10. For NEAMTWS purposes, the GFZ virtual real-time seismic network (GEOFON Extended Virtual Network -GEVN) in Europe was substantially extended by adding many stations from Western European countries optimizing the station distribution. In parallel to the data collection over the Internet, a GFZ VSAT hub for secured data collection of the EuroMED GEOFON and NEAMTWS backbone network stations became operational and first data links were established through this backbone. For the Southeast Asia region, a VSAT hub has been established in Jakarta already in 2006, with some other partner networks connecting to this backbone via the Internet. Since its establishment, the experimental system has had the opportunity to prove its performance in a number of relevant earthquakes. Reliable solutions derived from a minimum of 25 stations were very promising in terms of speed. For important events, automatic alerts were released and disseminated by emails and SMS. Manually verified solutions are added as soon as they become

  1. Influence of experimental parameters inherent to optical fibers on Quantum Key Distribution, the protocol BB84

    Directory of Open Access Journals (Sweden)

    L. Bouchoucha

    2018-03-01

    Full Text Available In this work, we represent the principle of quantum cryptography (QC that is based on fundamental laws of quantum physics. QC or Quantum Key Distribution (QKD uses various protocols to exchange a secret key between two communicating parties. This research paper focuses and examines the quantum key distribution by using the protocol BB84 in the case of encoding on the single-photon polarization and shows the influence of optical components parameters on the quantum key distribution. We also introduce Quantum Bit Error Rate (QBER to better interpret our results and show its relationship with the intrusion of the eavesdropper called Eve on the optical channel to exploit these vulnerabilities.

  2. THE EXPERIMENTAL DIDACTIC STAND FOR DETERMINING THE PARAMETERS OF THE GEAR WITH MAGNETORHEOLOGICAL CLUTCH AND BRAKE

    Directory of Open Access Journals (Sweden)

    Jerzy BAJKOWSKI

    2014-03-01

    Full Text Available In this paper the laboratory stand, designed to be used as a part of the Laboratory of Machine Design and Research which is part of the subject Fundamentals of Machine Design, is presented. Originally the laboratory stand was designed as an element of one of the research projects, and the adopted for didactic purposes. The students have the chance to get familiar with unique type of fluids controlled by the magnetic field and their application in the special purpose devices. The laboratory stand allows to conduct individual measurements of the torque, for different coil currents which generate the magnetic field. In the final report students provide the results with the individual analysis of the system parameters.

  3. Conceptual design study of fusion experimental reactor (FY86 FER)

    International Nuclear Information System (INIS)

    Saito, Ryusei; Kashihara, Shin-ichiro; Itoh, Shin-ichi

    1987-08-01

    This report describes the results of conceptual design study on plant systems for the Fusion Experimental Reactor (FY86 FER). Design studies for FER plant systems have been continued from FY85, especially for design modifications made in accordance with revisions of plasma scaling parameters and system improvements. This report describes 1) system construction, 2) site and reactor building plan, 3) repaire and maintenance system, 4) tritium circulation system, 5) heating, ventilation and air conditioning system, 6) tritium clean-up system, 7) cooling and baking system, 8) waste treatment and storage system, 9) control system, 10) electric power system, 11) site factory plan, all of which are a part of FY86 design work. The plant systems described in this report generally have been based on the FY86 FER (ACS Reactor) which is an one of the six candidates for FER. (author)

  4. Experimental basis for parameters contributing to energy dissipation in piping systems

    International Nuclear Information System (INIS)

    Ibanez, P.; Ware, A.G.

    1985-01-01

    The paper reviews several pipe testing programs to suggest the phenomena causing energy dissipation in piping systems. Such phenomena include material damping, plasticity, collision in gaps and between pipes, water dynamics, insulation straining, coupling slippage, restraints (snubbers, struts, etc.), and pipe/structure interaction. These observations are supported by a large experimental data base. Data are available from in-situ and laboratory tests (pipe diameters up to about 20 inches, response levels from milli-g's to responses causing yielding, and from excitation wave forms including sinusoid, snapback, random, and seismic). A variety of pipe configurations have been tested, including simple, bare, straight sections and complex lines with bends, snubbers, struts, and insulation. Tests have been performed with and without water and at zero to operating pressure. Both light water reactor and LMFBR piping have been tested

  5. Refined Dummy Atom Model of Mg(2+) by Simple Parameter Screening Strategy with Revised Experimental Solvation Free Energy.

    Science.gov (United States)

    Jiang, Yang; Zhang, Haiyang; Feng, Wei; Tan, Tianwei

    2015-12-28

    Metal ions play an important role in the catalysis of metalloenzymes. To investigate metalloenzymes via molecular modeling, a set of accurate force field parameters for metal ions is highly imperative. To extend its application range and improve the performance, the dummy atom model of metal ions was refined through a simple parameter screening strategy using the Mg(2+) ion as an example. Using the AMBER ff03 force field with the TIP3P model, the refined model accurately reproduced the experimental geometric and thermodynamic properties of Mg(2+). Compared with point charge models and previous dummy atom models, the refined dummy atom model yields an enhanced performance for producing reliable ATP/GTP-Mg(2+)-protein conformations in three metalloenzyme systems with single or double metal centers. Similar to other unbounded models, the refined model failed to reproduce the Mg-Mg distance and favored a monodentate binding of carboxylate groups, and these drawbacks needed to be considered with care. The outperformance of the refined model is mainly attributed to the use of a revised (more accurate) experimental solvation free energy and a suitable free energy correction protocol. This work provides a parameter screening strategy that can be readily applied to refine the dummy atom models for metal ions.

  6. Experimental microangiographic study in normal rabbit liver

    International Nuclear Information System (INIS)

    Kim, Yoon Gyoo; Park, Jong Yeon; Han, Kook Sang; Moon, Ki Ho; Choi, Chang Ho; Han, Koon Taek; Lee, Suck Hong; Kim, Byung Soo

    1994-01-01

    Microangiography is an experimental radiologic technique for evaluation of the morphology and the function of small vessels. The purpose of this study is to introduce a good microangiographic technique and to present the microangiographic appearance of normal hepatic vascular pattern. Five white rabbits weighing 2.5-2.9Kg were objected. Polyethylene catheters were inserted in portal vein and then in IVC. Heparin mixed normal saline (2cc/1000cc) was infused through portal vein and blood was drained to IVC. Barium suspension was infused via the catheter placed in portal vein until the liver surface showed satisfactory finding in barium filling. The liver was removed and this preparation was fixed in 10% formaline for 7 days. After fixation, the liver was sectioned on 1-2mm thickness. The slices were radiographed on high resolution plate using Faxitron. H-E staining of liver tissue was also done. The microbrium was well distributed in all small vessels without filling defect. And we could find the hexagonal shaped classic liver lobule, in which the central vein was located at central portion and portal vein at periphery. The enlargement was showed numerous sinusoids, but there was less dye in the central portion of lobule, but the central vein was well filled by microbarium. The peripheral portion of lobule was well filled with microbarium. So, we could find diamond shaped liver acinus, in which central vein was located at priperal portion and the center of liver acinus was terminal portal vein that growed out from a small portal space. The three acini made the complex acinus and acinar agglomerate was composed of three or four complex acini. It is considered that the liver acinus pattern of Rapparport is more acceptable on microangiography than the classic concept of hepatic lobule

  7. Experimental study and modelling of transient boiling

    International Nuclear Information System (INIS)

    Baudin, Nicolas

    2015-01-01

    A failure in the control system of the power of a nuclear reactor can lead to a Reactivity Initiated Accident in a nuclear power plant. Then, a power peak occurs in some fuel rods, high enough to lead to the coolant film boiling. It leads to an important increase of the temperature of the rod. The possible risk of the clad failure is a matter of interest for the Institut de Radioprotection et de Securite Nucleaire. The transient boiling heat transfer is not yet understood and modelled. An experimental set-up has been built at the Institut de Mecanique des Fluides de Toulouse (IMFT). Subcooled HFE-7000 flows vertically upward in a semi annulus test section. The inner half cylinder simulates the clad and is made of a stainless steel foil, heated by Joule effect. Its temperature is measured by an infrared camera, coupled with a high speed camera for the visualization of the flow topology. The whole boiling curve is studied in steady state and transient regimes: convection, onset of boiling, nucleate boiling, critical heat flux, film boiling and rewetting. The steady state heat transfers are well modelled by literature correlations. Models are suggested for the transient heat flux: the convection and nucleate boiling evolutions are self-similar during a power step. This observation allows to model more complex evolutions, as temperature ramps. The transient Hsu model well represents the onset of nucleate boiling. When the intensity of the power step increases, the film boiling begins at the same temperature but with an increasing heat flux. For power ramps, the critical heat flux decreases while the corresponding temperature increases with the heating rate. When the wall is heated, the film boiling heat transfer is higher than in steady state but it is not understood. A two-fluid model well simulates the cooling film boiling and the rewetting. (author)

  8. Water-clay interactions. Experimental study

    International Nuclear Information System (INIS)

    Gaucher, Eric

    1998-01-01

    Clay minerals contribute to the chemical composition of soil and sediment groundwaters via surface and dissolution/precipitation reactions. The understanding of those processes is still today fragmentary. In this context, our experimental purpose is to identify the contribution of each reaction in the chemical composition of water in a water/clay System. Kaolinite, illite, montmorillonite are the reference clays. After a fine mineralogical study, the exchange equilibria between K + and H + are characterised. Different exchange sites are identified and the exchange capacities and selectivity coefficients are quantified. Then, mixtures of the three clays are equilibrated with acidic and basic (I≤10 -2 M) solutions at 25 deg. C, 60 deg. C, 80 deg. C, during 320 days. The System evolution is observed by chemical analysis of the solutions and mineralogical analysis by TEM. We show that montmorillonite is unstable compared to the kaolinite/amorphous silica assemblage for solutions of pH<7. Aqueous silica is probably controlled by the kinetics of dissolution of the montmorillonite in moderate pH media. In more acidic solutions, amorphous silica precipitates. Al is under control of 'kaolinite' neo-formations. The use of the selectivity coefficients in a numerical simulation shows that K + concentration depends on exchange reactions. The pH has a more complicated evolution, which is not completely understood. This evolution depends on both exchange equilibria and organic acid occurrence. In this type of experiments, we have demonstrated that the equilibrium equations between smectite and kaolinite are inexact. The problem of the thermodynamic nature of clays remains and is not resolved by these solubility experiments. (author) [fr

  9. Parameter studies for a two-component fusion experiment

    International Nuclear Information System (INIS)

    Towner, H.H.

    1975-01-01

    The sensitivity of the energy multiplication of a two-component fusion experiment is examined relative to the following parameters: energy confinement time (tau/sub E/), particle confinement time (tau/sub p/), effective Z of the plasma (Z/sub eff/), injection rate (j/sub I/) and injection energy (E/sub I/). The Energy Research and Development Administration recently approved funding for such a fusion device (the Toroidal Fusion Test Reactor or TFTR) which will be built at the Princeton Plasma Physics Laboratory. Hence, such a parameter study seems both timely and necessary. This work also serves as an independent check on the design values proposed for the TFTR to enable it to achieve energy breakeven (F = 1). Using the nominal TFTR design parameters and a self-consistent ion-electron power balance, the maximum F-value is found to be approximately 1.2 which occurs at an injection energy of approximately 210 KeV. The injector operation, i.e. its current and energy capability are shown to be a very critical factor in the TFTR performance. However, if the injectors meet the design objectives, there appears to be sufficient latitude in the other parameters to offer reasonable assurance that energy breakeven can be achieved. (U.S.)

  10. Solar pond conception - experimental and theoretical studies

    Energy Technology Data Exchange (ETDEWEB)

    Kurt, Huseyin [Zonguldak Karaelmas Univ., Technical Education Faculty, Karabuk (Turkey); Halici, Fethi [Sakarya Univ., Mechanical Engineering Dept., Adapazari (Turkey); Binark, A. Korhan [Marmara Univ., Technical Education Faculty, Istanbul (Turkey)

    2000-07-01

    A one dimensional transient mathematical model for predicting the thermal performance of the salt gradient solar pond is developed and presented. In this paper, the natural solar ponds and different artificial solar pond systems found in the literature are introduced. Necessary modifications are made on the experimental stand located in Istanbul Technical University, the experimental stand is introduced and natural phenomena produced in the pond by the different solar pond variations under natural conditions are observed. In the theoretical work based on a one dimensional unsteady state heat conduction model with internal heat generation, the energy and mass balance equations for the upper convective zone, the non-convective zone and the lower convective zone, all of which form the solar pond, are written in terms of differential equations. These equations are solved analytically and numerically. The results obtained from the analysis are compared with the experimental results. The temperature and the concentration profiles are separately presented in the figures. (Author)

  11. An Experimental Study of an Offshore Platform

    DEFF Research Database (Denmark)

    Brincker, Rune; Asmussen, John Christian; Andersen, Palle

    of the multi-pile offshore platform is investigated by using a vibration based damage detection scheme. Changes in structural integrity are assumed to be reflected in the modal parameters estimated from only output data using an Auto-Regressive Moving Average (ARMA) model. Before the calibration of the ARMA...... model the quality of the measured data have been investigated. The estimated modal parameters and their corresponding variances are used as input to a probability based damage indicator. This indicator indicates, that since the construction of the platform, minor structural changes have taken place....

  12. Nuclear Criticality Technology and Safety Project parameter study database

    International Nuclear Information System (INIS)

    Toffer, H.; Erickson, D.G.; Samuel, T.J.; Pearson, J.S.

    1993-03-01

    A computerized, knowledge-screened, comprehensive database of the nuclear criticality safety documentation has been assembled as part of the Nuclear Criticality Technology and Safety (NCTS) Project. The database is focused on nuclear criticality parameter studies. The database has been computerized using dBASE III Plus and can be used on a personal computer or a workstation. More than 1300 documents have been reviewed by nuclear criticality specialists over the last 5 years to produce over 800 database entries. Nuclear criticality specialists will be able to access the database and retrieve information about topical parameter studies, authors, and chronology. The database places the accumulated knowledge in the nuclear criticality area over the last 50 years at the fingertips of a criticality analyst

  13. Geotechnical parameters for three deep ocean study areas

    International Nuclear Information System (INIS)

    Nicholson, D.P.

    1989-01-01

    This chapter summarizes the results of geotechnical measurements made on cores taken at the three deep ocean sites that have been studied in detail as part of the international programme assessing the feasibility of deep ocean disposal of heat-generating radioactive waste. The capabilities of existing sampling methods and the adequacy of the available data for providing the geotechnical parameters needed to evaluate the technical feasibility of deep ocean disposal are discussed. It is concluded that, while it has not been possible to obtain core samples of sufficient quality and depth to provide all the parameters needed for the assessment, no fundamental differences between the sediments at the study areas and those found on land or in shallow water have been identified. (author)

  14. Simulation and Experimental Determination of Technological Liquid Molding Parameters of Tubing Basalt Insulation

    Directory of Open Access Journals (Sweden)

    Yu. V. Badanina

    2015-01-01

    Full Text Available The article is dedicated to one of the most important and urgent tasks in mechanical engineering development - the creation of low-density and environmentally-friendly thermoinsulation from available cheap basalt fibers for products to operate at temperatures up to 700°C.One of the most effective applications of such thermo-insulation is to develop and provide highly porous coatings from short basalt fibers by liquid filtration for tubing (T to supply superheated up to 420° C steam under pressure of 35 MPa in the deep layers with severe highviscosity oil. Tubing with the short low-density basalt insulation can be used for a greater depth than the vacuum-insulated tubing, which are also called "thermo-cases", and do not fully meet business needs for long-term reliability of oil vacuum tubes, too large mass per unit length of their design and, as a consequence, the impossibility to use such pipes for deep wells.The aim of the work is to simulate a liquid filtration process of short fibers and determine technological parameters of producing thermal insulation coatings of tubing pipes from basalt fibers and mineral binder shaped as cylinders and cylindrical shells. The paper proposes a mathematical model of free filtration deposition of short fibers from liquid slurry, which describes dynamics of creating thermal insulation products and allows us to determine the rational parameters of their manufacturing process. It shows methods to improve the products quality while forming the thermal insulation by filtration through additional vacuum deposition of a filtrate chamber and the final prepressing of sediment layer, giving dimensions and shape to the final product.The paper defines a prescription hydro mass composition. It shows that to increase the compressive strength of highly fibrous rings and cylindrical shells it is necessary to use based on oxide А12O3 5-7% by weight mineral binder, which fixes basalt fibers in places of their contacts. It

  15. An Experimental Seismic Data and Parameter Exchange System for Interim NEAMTWS

    Science.gov (United States)

    Hanka, W.; Hoffmann, T.; Weber, B.; Heinloo, A.; Hoffmann, M.; Müller-Wrana, T.; Saul, J.

    2009-04-01

    In 2008 GFZ Potsdam has started to operate its global earthquake monitoring system as an experimental seismic background data centre for the interim NEAMTWS (NE Atlantic and Mediterranean Tsunami Warning System). The SeisComP3 (SC3) software, developed within the GITEWS (German Indian Ocean Tsunami Early Warning System) project was extended to test the export and import of individual processing results within a cluster of SC3 systems. The initiated NEAMTWS SC3 cluster consists presently of the 24/7 seismic services at IMP, IGN, LDG/EMSC and KOERI, whereas INGV and NOA are still pending. The GFZ virtual real-time seismic network (GEOFON Extended Virtual Network - GEVN) was substantially extended by many stations from Western European countries optimizing the station distribution for NEAMTWS purposes. To amend the public seismic network (VEBSN - Virtual European Broadband Seismic Network) some attached centres provided additional private stations for NEAMTWS usage. In parallel to the data collection by Internet the GFZ VSAT hub for the secured data collection of the EuroMED GEOFON and NEAMTWS backbone network stations became operational and the first data links were established. In 2008 the experimental system could already prove its performance since a number of relevant earthquakes have happened in NEAMTWS area. The results are very promising in terms of speed as the automatic alerts (reliable solutions based on a minimum of 25 stations and disseminated by emails and SMS) were issued between 2 1/2 and 4 minutes for Greece and 5 minutes for Iceland. They are also promising in terms of accuracy since epicenter coordinates, depth and magnitude estimates were sufficiently accurate from the very beginning, usually don't differ substantially from the final solutions and provide a good starting point for the operations of the interim NEAMTWS. However, although an automatic seismic system is a good first step, 24/7 manned RTWCs are mandatory for regular manual verification

  16. Experimental studies of rotating exchange flow

    Science.gov (United States)

    Rabe, B.; Smeed, D. A.; Dalziel, S. B.; Lane-Serff, G. F.

    2007-02-01

    Ocean basins are connected by straits and passages, geometrically limiting important heat and salt exchanges which in turn influence the global thermohaline circulation and climate. Such exchange can be modeled in an idealized way by taking into consideration the density-driven two-layer flow along a strait under the influence of rotation. We use a laboratory model of a lock exchange between two reservoirs of different density through a flat-bottom channel with a horizontal narrows, set up on two different platforms: a 1 m diameter turntable, where density interface position was measured by dye attenuation, and the 14 m diameter turntable at Coriolis/LEGI (Grenoble, France), where correlation imaging velocimetry, a particle imaging technique, allowed us to obtain for the first time detailed measurements of the velocity fields in these flows. The influence of rotation is studied by varying a parameter, Bu, a type of Burger number given by the ratio of the Rossby radius to the channel width at the narrows. In addition, a two-layer version of the Miami Isopycnic Coordinate Model (MICOM) is used, to study the cases with low Burger number. Results from experiments by Dalziel [1988. Two-layer hydraulics: maximal exchange flows. Ph.D. Thesis, Department of Applied Mathematics and Theoretical Physics, University of Cambridge, see also people/sd103/papers/1988/Thesis_Dalziel.pdf>] are also included for comparison. Time-mean exchange fluxes for any Bu are in close agreement with the inviscid zero-potential vorticity theory of Dalziel [1990. Rotating two-layer sill flows. In: Pratt, L.J. (Ed.), The Physical Oceanography of Sea Straits. Kluwer Academic, Dordrecht, pp. 343-371] and Whitehead et al. [1974. Rotating hydraulics of strait and sill flows. Geophysical Fluid Dynamics 6, 101-125], who found that fluxes for Bu>1 mainly vary with channel width, similar to non-rotating flow, but for Bu1 a steady, two-layer flow was observed that persisted across the channel at the narrows

  17. Theoretical study of Moessbauer hyperfine parameters of Fe bound to ammonia

    International Nuclear Information System (INIS)

    Terra, J.; Guenzburger, D.

    1995-01-01

    The first-principles Discrete Variational method was employed to study the species formed by the interaction of an Fe atom and ammonia. Total energy calculations were performed for several configurations. The hyperfine parameters isomer shift, quadrupole splitting and magnetic hyperfine were calculated for the ground state found, and compared to reported experimental values obtained by Moessbauer spectroscopy in frozen ammonia. (author). 14 refs, 1 tab

  18. Experimental researches of marine wave parameters in the Black Sea Basin

    Science.gov (United States)

    Panaitescu, Fanel-Viorel; Panaitescu, Mariana; Anton, Iulia-Alina

    2016-12-01

    In this paper are presented the process of measuring parameters of marine waves with performed devices which permit to obtain the values of the speed and current division marine wave amplitude and direction of the wave at each measurement, the number of measurements, date, hour, minute and second of measurement. This monitoring, which comprises the period of one year including, reveals an amplitude an annual average of the wave of hmed=1.53 m, obtained by taking maximum envelope appeared in a measurement range of 120 seconds. The value is unexpectedly high, taking into account of the fact that on the coastline it was found of: hmed =0.467 m at Constanta Station and hmed =0.23 m at Mangalia Station. These results reveal that there is a energy potential that exceeds expectations, much larger in the area of off shore, that is to say, in more than 12 Mm off shore, in front of the coastal zone. These measurements were applied with two devices-one device for measuring hidrostatic amplitude test and other device, ADV(Advanced Doppler velocymmeter).

  19. Theoretical and experimental evaluation of piezo-optic parameters and photoelastic constant in tetragonal PWO.

    Science.gov (United States)

    Natali, Pier Paolo; Montalto, Luigi; Daví, Fabrizio; Mengucci, Paolo; Ciriaco, Andrea; Paone, Nicola; Rinaldi, Daniele

    2018-02-01

    The tetragonal PbWO 4 (PWO) is one of the most important scintillating crystals, being used both in the Compact Muon Solenoid (CMS) experiment at the European Organization for Nuclear Research (CERN) and in the PANDA project at the Facility for Antiproton and Ion Research (FAIR). Light yield and other relevant scintillation properties depend, among many factors, also on the crystal mechanical quality. Accordingly, a detailed knowledge of crystal piezo-optic properties is a mandatory step toward understanding elasto-optic behavior and performing crystal quality control. In this paper, we evaluate for the first time, to the best of our knowledge, by means of both photoelastic and x-ray measurements, some components of the piezo-optic tensor; moreover, when the crystal is acted upon by a uniaxial stress, we obtain an evaluation for the rotation angle of the optic plane under stress as well as the photoelastic constant. These parameters are necessary to detect the residual stresses within the crystal, if any, and to give an overall quality measure. Such a methodology is in general suitable for any tetragonal crystals.

  20. Preventive effects of hydroalcoholic extract of saffron on hematological parameters of experimental asthmatic rats

    Directory of Open Access Journals (Sweden)

    Somayyeh Vosooghi

    2013-05-01

    Full Text Available Objective: Asthma is a chronic inflammatory disease of the respiratory airways distinguished by edema and infiltration of inflammatory immune cells. To test our hypothesis about the anti-inflammatory effect of saffron, we examined effects of Crocus sativus (C. sativus extract as a prophylactic anti-inflammatory agent in sensitized rats. Materials and Methods: To induce experimental asthma, rats were sensitized with injection and inhalation of ovalbumin (OA. Forty male Wistar rats were divided into 5 groups (n=8 for each: control, sensitized (asthma, and sensitized and pretreated with three different concentrations of extract, 50, 100, and 200 mg/kg, 2 times a week (group asthma+50EX, group asthma+100EX, and group asthma+200EX. After 32 days, total white blood cells (WBC counts, red blood cells (RBC, and platelet counts in blood were examined. Results: Total WBC number and eosinophil and neutrophil percentage in blood were increased, but lymphocyte decreased in sensitized animals compared with those of control group (pConclusion: Our findings indicated that the extract of C. sativus could be useful to prevent asthma as an anti-inflammatory treatment.

  1. Monte Carlo calculations and experimental measurements of dosimetric parameters of the IRA-103Pd brachytherapy source

    International Nuclear Information System (INIS)

    Sadeghi, Mahdi; Raisali, Gholamreza; Hosseini, S. Hamed; Shavar, Arzhang

    2008-01-01

    This article presents a brachytherapy source having 103 Pd adsorbed onto a cylindrical silver rod that has been developed by the Agricultural, Medical, and Industrial Research School for permanent implant applications. Dosimetric characteristics (radial dose function, anisotropy function, and anisotropy factor) of this source were experimentally and theoretically determined in terms of the updated AAPM Task group 43 (TG-43U1) recommendations. Monte Carlo simulations were used to calculate the dose rate constant. Measurements were performed using TLD-GR200A circular chip dosimeters using standard methods employing thermoluminescent dosimeters in a Perspex phantom. Precision machined bores in the phantom located the dosimeters and the source in a reproducible fixed geometry, providing for transverse-axis and angular dose profiles over a range of distances from 0.5 to 5 cm. The Monte Carlo N-particle (MCNP) code, version 4C simulation techniques have been used to evaluate the dose-rate distributions around this model 103 Pd source in water and Perspex phantoms. The Monte Carlo calculated dose rate constant of the IRA- 103 Pd source in water was found to be 0.678 cGy h -1 U -1 with an approximate uncertainty of ±0.1%. The anisotropy function, F(r,θ), and the radial dose function, g(r), of the IRA- 103 Pd source were also measured in a Perspex phantom and calculated in both Perspex and liquid water phantoms

  2. Experimental Study of a Thermoelectric Generation System

    DEFF Research Database (Denmark)

    Zhu, Junpeng; Gao, Junling; Chen, Min

    2011-01-01

    . System-level simulation is carried out using a quasi-one-dimensional numerical model that enables direct comparison with experimental results. The results of both experiment and simulation will provide a foundation to improve and optimize complex thermoelectric generation systems....

  3. Experimental methods to study tokamak plasma stability

    International Nuclear Information System (INIS)

    Perez-Navarro, A.

    1978-01-01

    Experimental devices to measure external instability modes with small pick-up coils to detect poloidal magnetic field fluctuations, and internal modes with soft-X-ray detectors are discussed. The characteristics of these devices are calculated for a small tokamak (R 0 = 30 cm, a = 10 cm, I 0 50 KA). (author)

  4. Blast mitigation experimental and numerical studies

    CERN Document Server

    2013-01-01

    Presents experimental methods of material and structural response to dynamic blast loads Includes computational analysis of material and structural response to dynamic blast loads Offers mitigation measures for structures in various environments Relates lab experiments to larger field tests Features more than 150 illustrations

  5. Auctioning incentive contracts: an experimental study

    NARCIS (Netherlands)

    Onderstal, S.; van de Meerendonk, A.

    2009-01-01

    In this note, we experimentally examine the relative performance of price-only auctions and multi-attribute auctions. We do so in procurement settings where the buyer can give the winning bidder incentives to exert effort on non-price dimensions after the auction. Both auctions theoretically

  6. Study of Sperm Parameters and Sperm Fertility in Mice were Exposed to Tamoxifen during Embryonic Development

    Directory of Open Access Journals (Sweden)

    J Soleimanirad

    2017-05-01

    Full Text Available Introduction: Tamoxifen is steroidal drug, which mainly treats breast cancer and also used to stimulate ovulation. The purpose of the present study was the evaluation of sperm parameters and fertility of mice whose mothers had received tamoxifen during pregnancy. Methods: In this study, 30 female and 15 male mice of NMRI were selected for mating. After mating female mice were randomly divided into two groups, the first group (control and second group (experimental. All of which contained 15 mice. From the day 13th day of pregnancy, experimental group has received tamoxifen with the dosage of 5 mg/kg for 7 days. After childbirth of the mated mice, male infants were selected. After reaching the age of puberty (6-8Weeks, adult mice were sacrificed by the cervical dislocation. After take sperm, sperm parameters (count, normality and motility, and sperm fertility was performed. In this study SPSS software and statistical t-test was used (p <0.001. Results: Studies showed that sperm parameters and sperm fertilization were significantly different. The number of sperm in the control group was 83.50±28.20 million, and in the experimental group was 60±14.14 million. There was a decrease in average sperm count in the experimental group compared with the control group (p <0.001. Our findings from in vitro fertilization culture media showed that embryos formation and oocyte disruption between control and experimental groups significantly different (p <0.001. Conclusion: The results showed that tamoxifen exposure during development can cause histological changes in the seminiferous tubules, which can lead to infertility.

  7. Effects of isolated vitamin B6 supplementation on oxidative stress and heart function parameters in experimental hyperhomocysteinemia

    Directory of Open Access Journals (Sweden)

    Roberta Hack Mendes

    2017-07-01

    Full Text Available Introduction: The purpose of this study was to investigate the effects of isolated vitamin B6 (VB6 supplementation on experimental hyperhomocysteinemia (Hhe induced by homocysteine thiolactone (HcyT. Methods: Fifteen male Wistar rats were divided into three groups according to their treatment. Animals received water and food ad libitum and an intragastric probe was used to administer water for 60 days (groups: CB6, HcyT, and HB6. On the 30th day of treatment, two groups were supplemented with VB6 in the drinking water (groups: CB6 and HB6. After 60 days of treatment, homocysteine (Hcy, cysteine, and hydrogen peroxide concentration, nuclear factor (erythroid-derived 2-like 2 (NRF2 and glutathione S-transferase (GST immunocontent, and superoxide dismutase (SOD, catalase (CAT, and GST activities were measured. Results: The HcyT group showed an increase in Hcy concentration (62% in relation to the CB6 group. Additionally, GST immunocontent was enhanced (51% in the HB6 group compared to the HcyT group. Also, SOD activity was lower (17% in the HB6 group compared to the CB6 group, and CAT activity was higher in the HcyT group (53% compared to the CB6 group. Ejection fraction (EF was improved in the HB6 group compared to the HcyT group. E/A ratio was enhanced in the HB6 group compared to the CB6 group. Correlations were found between CAT activity with myocardial performance index (MPI (r = 0.71; P = 0.06 and E/A ratio (r = 0.6; P = 0.01, and between EF and GST activity (r = 0.62; P = 0.02. Conclusions: These findings indicate that isolated VB6 supplementation may lead to the reduction of Hcy concentration and promotes additional benefits to oxidative stress and heart function parameters.   Keywords: Homocysteine; oxidative stress; vitamin B6.

  8. Numerical and Experimental Study of Friction Loss in Hydrostatic Motor

    DEFF Research Database (Denmark)

    Sørensen, Rasmus Mørk; Hansen, Michael R.; Mouritsen, Ole Ø.

    2012-01-01

    This paper presents a numerical and experimental study of the losses in a hydrostatic motor principle. The motor is designed so that the structural de ections and lubricating regimes between moving surfaces and, subsequently, the leakage and friction losses, can be controlled during operation....... This is done by means of additional pressure volumes that in uence the stator de ection. These pressures are referred to as compensation pressures and the main emphasis is on friction or torque loss modeling of the motor as a function of the compensation pressures and the high and low pressures related...... to the load torque. The torque loss modeling is identied as a Stribeck curve which depends on gap height. The asperity friction is decreasing exponentially with an increase in gap height. The parameters of the torque loss model are based on prototype measurements that include the structural de ections...

  9. An experimental study on improvement of Savonius rotor performance

    Directory of Open Access Journals (Sweden)

    N.H. Mahmoud

    2012-03-01

    In this work different geometries of Savonius wind turbine are experimentally studied in order to determine the most effective operation parameters. It was found that, the two blades rotor is more efficient than three and four ones. The rotor with end plates gives higher efficiency than those of without end plates. Double stage rotors have higher performance compared to single stage rotors. The rotors without overlap ratio (β are better in operation than those with overlap. The results show also that the power coefficient increases with rising the aspect ratio (α. The conclusions from the measurements of the static torque for each rotor at different wind speeds verify the above summarized results of this work.

  10. Experimental study of multi-component separation by gas centrifuge

    International Nuclear Information System (INIS)

    Zhou, M.S.; Liang, X.W.; Chen, W.N.; Yin, Y.T.

    2006-01-01

    Stable isotopes are applied in many areas and most stable isotopes are multi-component, This paper presents experimental results of several stable isotopes separation conducted in Tsinghua University by using ultra-speed gas centrifuges. Xe, WF 6 , TeF 6 , SiHCl 3 , SiF 4 were chosen as the process gases. By adjusting some of the centrifuge's parameters, the suitable centrifuge parameters for different process gas separations were found and the overall unit separation factors γ 0 were obtained by means of single gas centrifuge separation. The experimental results show that with appropriate process gases, stable isotope separation by gas centrifuge was effective. (authors)

  11. Study of some physiological parameters among mobile phone users

    International Nuclear Information System (INIS)

    Anwar, S.M.; Gabr, S.A.

    2002-01-01

    Forty male mobile users in additional to twenty males as control group similar in age and socio economically matched were chosen for this study. Blood pressure, complete blood picture, five parameters of semen quality and four sex hormones (LH, FSH, prolactin and testosterone)were measured. Elevated significant differences for blood pressure (P<0.01) for the exposed group and some changes in mean values of haematologic parameters, although all values were within the normal range. Minor semen quality and hormonal levels changes between the two groups, including a higher mean follicle-stimulating hormone level; for mobile users (8.10 vs 6.00 mIU/mL), and a slightly higher mean luteinizing hormone level (11.73 vs 10.16 mLU/mL) were noted in the user group

  12. Seismic analysis of steam generator and parameter sensitivity studies

    International Nuclear Information System (INIS)

    Qian Hao; Xu Dinggen; Yang Ren'an; Liang Xingyun

    2013-01-01

    Background: The steam generator (SG) serves as the primary means for removing the heat generated within the reactor core and is part of the reactor coolant system (RCS) pressure boundary. Purpose: Seismic analysis in required for SG, whose seismic category is Cat. I. Methods: The analysis model of SG is created with moisture separator assembly and tube bundle assembly herein. The seismic analysis is performed with RCS pipe and Reactor Pressure Vessel (RPV). Results: The seismic stress results of SG are obtained. In addition, parameter sensitivities of seismic analysis results are studied, such as the effect of another SG, support, anti-vibration bars (AVBs), and so on. Our results show that seismic results are sensitive to support and AVBs setting. Conclusions: The guidance and comments on these parameters are summarized for equipment design and analysis, which should be focused on in future new type NPP SG's research and design. (authors)

  13. Experimental Study on Flexural Strength of Reinforced Geopolymer Concrete Beams

    OpenAIRE

    Khoa Tan Nguyen; Tuan Anh Le; Kihak Lee

    2016-01-01

    This paper presents the flexural response of Reinforced Geopolymer Concrete (RGPC) beams. A commercial finite element (FE) software ABAQUS has been used to perform a structural behavior of RGPC beams. Using parameters such: stress, strain, Young’s modulus, and Poisson’s ratio obtained from experimental results, a beam model has been simulated in ABAQUS. The results from experimental tests and ABAQUS simulation were compared. Due to friction forces at the supports and loading rollers; slip occ...

  14. Korean experimental studies on the radionuclide transfer in crop plants

    International Nuclear Information System (INIS)

    Choi, Y.H.; Lim, K.M.; Choi, G.S.; Choi, H.J.; Lee, H.S.; Lee, C.W.

    2003-01-01

    In Korea, data on the radionuclide transfer in crop plants have been produced almost exclusively at the Korea Atomic Energy Research Institute (KAERI), where experimental studies have been carried out for last about 20 years. These works are briefly outlined in this paper which shows results with emphasis on rice data. Soil-to-plant transfer factors of radionuclides including radiocesium and radiostrontium were measured through greenhouse experiments for various crop species. Not only conventional transfer factors but also those based on the activity applied to unit area of the soil surface were investigated. Field studies on the transfer of fallout 137 Cs were carried out for rice and Chinese cabbage. As for parameters in relation to direct plant contamination, interception factors and translocation factors were obtained through greenhouse experiments. Plants were sprayed with radioactive solutions containing 54 Mn, 57 Co, 85 Sr, 103 Ru and 134 Cs at different growth stages. Experiments on the plant exposure to airborne HTO and I 2 vapor were also carried out. The transfer parameters generally showed great variations with soils, crops, radionuclides and isotope application times. Most experiments were designed for acute releases of radioactivity but some results are applicable to steady-state conditions, too. Many of the produced data would be of use also in other countries including Japan. (author)

  15. Experimental study on performance of pulsed liquid jet pump

    International Nuclear Information System (INIS)

    Xu Weihui; Gao Chuanchang; Qin Haixia

    2010-01-01

    The device performance characteristics of transformer type pulsed liquid pump device were experimentally studied. The effects of the area ratio, work pressure and pulse parameters on the performance of the pulsed liquid jet pump device were performed in the tests. The potency of pulsed jet on improving the performance of the liquid jet pump device was also studied through the comparison with invariable jet pump at the same conditions. The results show that the pulsed jet can significantly improve the performance of transformer type jet pump devices. Area ratio and pulse parameters are the critical factors to the performance of the pulsed liquid jet pump device. The jet pump device performances are significantly improved by reducing the area ratio or by increasing the pulsed frequency. The flux characteristics of the pulsed liquid jet pump device presents the typical negative linear,the potency of pulsed jet in improving the performance of jet pump device with small area ratio can be more significant. The efficiency curve of pulsed liquid jet pump is similar to the parabola. At higher pulsed frequency, the top efficiency point of the pulsed jet pump moves to the higher flow ratio. The high efficiency area of the pulsed jet pump also is widened with the increase of the pulsed frequency. (authors)

  16. Further optimization studies of experimental dynamic responses measured on the HTGC Dragon reactor

    International Nuclear Information System (INIS)

    Cummins, J.D.

    1968-04-01

    This report considers some measurements made of the dynamics of the HTGC Dragon reactor and the optimization of a mathematical model which represents the reactor, by altering the parameters until a least squares fit between the experimental responses and the mathematical model is obtained. The experimental information was processed in various ways. The experimental response to an impulse, step or periodic sine wave change in reactivity was processed as an impulse, step or periodic sine wave response respectively and compared with a similar response from the model. In other studies the result of a binary cross correlation experiment (effectively an impulse response input) was processed as a frequency response and this experimental frequency response was compared with the frequency response from the mathematical model. It was possible therefore to compare the optimum values of parameters, obtained for different forms of perturbing signal and for different methods of processing and to relate the optima obtained to the problem of parameter estimation. (author)

  17. Experimental and numerical studies of rotating drum grate furnace

    Directory of Open Access Journals (Sweden)

    Basista Grzegorz

    2017-01-01

    Full Text Available Waste material from the meat industry can be taken into account as a biofuel. Studies confirm, that calorific value is higher and ash content is lower comparing to some conventional fuels. EU directives regulate details of thermal disposal of the waste material from the meat industry - especially in range of the process temperature and time of the particle presence in area of the combustion zone. The paper describes design of the rotating drum grate stove, dedicated to thermal disposal of the meat wastes as well as solid biomass (pellet, small bricket, wood chips combustion. Device has been developed in frames of cooperation between AGH University of Science and Technology (Krakow, Poland and producer focused on technologies of energy utilization of biomass in distributed generation. Results of measurements of selected operational parameters performed during startup of the furnace have been presented and discussed. Furthermore, numerical model of the combustion process has been developed to complement experimental results in range of the temperature and oxygen distribution in the area of the combustion chamber. ANSYS CFX solver has been applied to perform simulations including rotational domain related with specifics of operation of the device. Results of numerical modelling and experimental studies have been summarized and compared.

  18. Experimental study on generation of large area uniform electron beam

    International Nuclear Information System (INIS)

    Tang Ying; Yi Aiping; Liu Jingru; Qian Hang; Huang Xin; Yu Li; Su Jiancang; Ding Zhenjie; Ding Yongzhong; Yu Jianguo

    2007-01-01

    In the experiment of gas laser pumped by electron beam, large area uniform electron beam is important to generate high efficiency laser output. The experimental study on generation of large area uniform electron beam with SPG-200 pulsed power generator is introduced. SPG-200 is an all-solid-state components pulsed power generator based on SOS, and its open voltage is more than 350 kV. The cathode have the area of 24 mm x 294 mm, and the anode-cathode(A-C)gap spacing is adjustable from 0 to 49 mm. The electron beam of cathode emission is transported to the laser chamber through the diode pressure foil, which sepa-rates the vacuum chamber from the laser chamber. Velvet and graphite cathodes are studied, each generates large area electron beam. The diode parameters are presented, and the uniformity of e-beam is diagnosed. The experimental results show that the diode voltage of the graphite cathode is 240-280 kV, and the diode current is 0.7-1.8 kA. The diode voltage of the velvet cathode is 200-250 kV, and the diode current is 1.5-1.7 kA. The uniformity of the velvet cathode emission is better than that of the graphite cathode. (authors)

  19. Method to deterministically study photonic nanostructures in different experimental instruments

    NARCIS (Netherlands)

    Husken, B.H.; Woldering, L.A.; Blum, Christian; Tjerkstra, R.W.; Vos, Willem L.

    2009-01-01

    We describe an experimental method to recover a single, deterministically fabricated nanostructure in various experimental instruments without the use of artificially fabricated markers, with the aim to study photonic structures. Therefore, a detailed map of the spatial surroundings of the

  20. Experimental studies of Steel Corrugated Constructions

    Directory of Open Access Journals (Sweden)

    Lazarev Yuriy

    2016-01-01

    Full Text Available The purpose of this particular article is to assess existing calculations of steel corrugated constructions. Steel Corrugated Construction is a perspective type of constructions, which is exhibiting numerous advantages in comparison with one that currently applied in automobile and railroad networks (reinforced concrete water-throughput pipes, reinforced concrete frame bridges. The evaluation of experimental data on models of constructions of this particular type has been carried out in order to improve calculations of Steel Corrugated Constructions.

  1. [Crystalline lens photodisruption using femtosecond laser: experimental study].

    Science.gov (United States)

    Chatoux, O; Touboul, D; Buestel, C; Balcou, P; Colin, J

    2010-09-01

    The aim of this study was to analyze the interactions during femtosecond (fs) laser photodisruption in ex vivo porcine crystalline lenses and to study the parameters for laser interaction optimization. An experimental femtosecond laser was used. The laser characteristics were: 1030 nm wavelength; pulse duration, 400 fs; and numerical aperture, 0.13. Specific software was created to custom and monitor any type of photoablation pattern for treatment purposes. Porcine crystalline lenses were placed in an open sky holder filled with physiological liquid (BSS) covered by a glass plate. A numerical camera was associated with metrological software in order to magnify and quantify the results. Transmission electron microscopy (TEM) was performed on some samples to identify the microscopic plasma interactions with the lens. The optimization of parameters was investigated in terms of the optical breakdown threshold, the sizing of interactions, and the best pattern for alignments. More than 150 crystalline lenses of freshly enucleated pigs were treated. The optical breakdown threshold (OBT) was defined as the minimal energy level per pulse necessary to observe a physical interaction. In our study, the OBT varied according to the following parameters: the crystalline lens itself, varying from 4.2 to 7.6 μJ (mean, 5.1 μJ), and the depth of laser focus, varying up to 1 μJ, increasing in the depth of the tissue. Analyzing the distance between impacts, we observed that the closer the impacts were the less power was needed to create a clear well-drawn defect pattern (lines), i.e., with a 4-μJ optimized OBT, when the impacts were placed every 2 μm for the x,y directions and 60 μm for the z direction. Coalescent bubbles created by plasma formation always disappeared in less than 24h. The nonthermal effect of plasma and the innocuousness on surrounding tissues were proven by the TEM results. The crystalline lens photodisruption by the femtosecond laser seems an innovative

  2. Experimental determination of submicron aerosol dry deposition velocity onto rural canopies: influence of aerosol size, of micro meteorological parameters and of the substrate

    International Nuclear Information System (INIS)

    Damay, P.

    2010-04-01

    To evaluate the impact of accidental or chronic pollutant releases on ecosystems, we must study the dry deposition of aerosols in rural areas. The lack of experimental data on the dry deposition velocity of particle sizes below 1 μm over rural environments leads to uncertainties regarding models and differences between them, which exceed one order of magnitude. The aim of this study is to develop a method, especially using an Electrical Low Pressure Impactor (Outdoor ELPIDEKATI) to determine aerosol dry deposition velocities (Vd) over rural areas through experimental measurements. This method is based on eddy covariance flux calculation and spectral analysis correction. Dry deposition velocities were obtained for atmospheric aerosols sizing from 7 nm to 2 μm, in the South-West of France on a flat terrain under varied meteorological conditions and varied substrates (maize, grass and earth). Vd was analysed as a function of the particle diameters, and the impact of micro meteorological parameters was studied. (author)

  3. POPULATION SYNTHESIS OF HOT SUBDWARFS: A PARAMETER STUDY

    International Nuclear Information System (INIS)

    Clausen, Drew; Wade, Richard A.; Kopparapu, Ravi Kumar; O'Shaughnessy, Richard

    2012-01-01

    Binaries that contain a hot subdwarf (sdB) star and a main-sequence companion may have interacted in the past. This binary population has historically helped determine our understanding of binary stellar evolution. We have computed a grid of binary population synthesis models using different assumptions about the minimum core mass for helium ignition, the envelope binding energy, the common-envelope ejection efficiency, the amount of mass and angular momentum lost during stable mass transfer, and the criteria for stable mass transfer on the red giant branch and in the Hertzsprung gap. These parameters separately and together can significantly change the entire predicted population of sdBs. Nonetheless, several different parameter sets can reproduce the observed subpopulation of sdB + white dwarf and sdB + M dwarf binaries, which has been used to constrain these parameters in previous studies. The period distribution of sdB + early F dwarf binaries offers a better test of different mass transfer scenarios for stars that fill their Roche lobes on the red giant branch.

  4. Study of Temperature Coefficients for Parameters of Photovoltaic Cells

    Directory of Open Access Journals (Sweden)

    Daniel Tudor Cotfas

    2018-01-01

    Full Text Available The temperature is one of the most important factors which affect the performance of the photovoltaic cells and panels along with the irradiance. The current voltage characteristics, I-V, are measured at different temperatures from 25°C to 87°C and at different illumination levels from 400 to 1000 W/m2, because there are locations where the upper limit of the photovoltaic cells working temperature exceeds 80°C. This study reports the influence of the temperature and the irradiance on the important parameters of four commercial photovoltaic cell types: monocrystalline silicon—mSi, polycrystalline silicon—pSi, amorphous silicon—aSi, and multijunction InGaP/InGaAs/Ge (Emcore. The absolute and normalized temperature coefficients are determined and compared with their values from the related literature. The variation of the absolute temperature coefficient function of the irradiance and its significance to accurately determine the important parameters of the photovoltaic cells are also presented. The analysis is made on different types of photovoltaics cells in order to understand the effects of technology on temperature coefficients. The comparison between the open-circuit voltage and short-circuit current was also performed, calculated using the temperature coefficients, determined, and measured, in various conditions. The measurements are realized using the SolarLab system, and the photovoltaic cell parameters are determined and compared using the LabVIEW software created for SolarLab system.

  5. A study of operating parameters on the linear spark ignition engine

    International Nuclear Information System (INIS)

    Lim, Ocktaeck; Hung, Nguyen Ba; Oh, Seokyoung; Kim, Gangchul; Song, Hanho; Iida, Norimasa

    2015-01-01

    Highlights: • An experimental and simulation study of a linear engine is conducted. • The effects of operating parameters on the generating power are investigated. • The air gap length has a significant influence on the generating power. • The generating power of the linear engine is optimized with the value of 111.3 W. • There are no problems for the linear engine after 100 h of durable test. - Abstract: In this paper, we present our experiment and simulation study of a free piston linear engine based on operating conditions and structure of the linear engine for generating electric power. The free piston linear engine includes a two-stroke free piston engine, linear generators, and compressors. In the experimental study, the effects of key parameters such as input caloric value, equivalence ratio, spark timing delay, electrical resistance, and air gap length on the piston dynamics and electric power output are investigated. Propane is used as a fuel in the free piston linear engine, and it is premixed with the air to make a homogeneous charge before go into the cylinder. The air and fuel mass flow rate are varied by a mass flow controller. The experimental results show that the maximum generating power is found with the value of 111 W at the input caloric value of 5.88 kJ/s, spark timing delay of 1.5 ms, equivalence ratio of 1.0, electric resistance of 30 Ω, and air gap length of 1.0 mm. In order to check the durability of the linear engine, a durable test is conducted during 100 h. The experimental results show that there are no problems for the linear engine after about one hundred hours of the durable test. Beside experimental study, a simulation study is conducted to predict operating behavior of the linear engine. In the simulation study, the two-stroke free piston linear engine is modeled and simulated through a combination of three mathematical models including a dynamic model, a linear alternator model and a thermodynamic model. These

  6. Experimental studies of coaxial plasma gun current

    International Nuclear Information System (INIS)

    Price, D.W.

    1988-01-01

    In this investigation of a coaxial plasma gun, plasma sheath currents and related behavior are examined. Plasma behavior in the gun affects gun characteristics. Plasma gun applications are determined by the plasma behavior. The AFWL PUFF capacitor bank (72 μF, 29 nH, 120 kV) drives the plasma gun using a deuterium fill gas. The gas breakdown site is isolated from the dielectric/vacuum interface in the AFWL system. Two gas values deliver gas in the system. The first delivers gas from the gun breech and the second optional valve delivers gas to the gun muzzle. Currents and voltages are measured by Rogowski coils, B probes and capacitive voltage probes. A O-D slug model is used to predict the current, inductance, gun voltage and plasma sheath velocity. The slug model assumes the sheath transits the gun with all mass in the sheath. In the snowplow mode, the plasma sheath is thin with a sharp current rise and drop. Our system operated in a transition mode between the snowplow and deflagration modes with early snowplow behavior and late deflagration behavior. Neutrons are produced in a plasma pinch at the gun muzzle, indicating snowplow behavior. The slug theory models overall gun behavior to experimental accuracy. Experimental results are compared to four theories for plasma sheath velocities: the Alfven collisionally limited model, the Rosenbluth model, the Fishbine saturated model and a single particle drift model. Experimental velocities vary from 10 5 to 10 6 m/s. Only the single particle drift and the slug model calculations are of the right magnitude (8 x 10 5 m/s). The Fishbine and the Rosenbluth models predict slower velocities (2 x 10 5 m/s). The Alfven model is not applicable to this system

  7. Experimental Study of Cavitation in Laminar Flow

    OpenAIRE

    Croci , Kilian; Ravelet , Florent; ROBINET , Jean-Christophe; Danlos , Amélie

    2017-01-01

    An experimental setup has been especially developed in order to observe cavitation in laminar flows. Experiments have been carried out with a silicon oil of viscosity υ = 100cSt passing through a Venturi-type geometry with 18°/8° convergent/divergent angles respectively. The range of Reynolds numbers at the inlet section is between 350 and 1000. Two dynamic regimes are identified. They are characterized by two critical Reynolds numbers, induced by major hydrodynamic changes in the flow, in ad...

  8. Experimental studies of spallation on thin target

    International Nuclear Information System (INIS)

    Borne, F.; Crespin, S.; Drake, D.; Frehaut, J.; Ledoux, X.; Lochard, J.P.; Martinez, E.; Patin, Y.; Petibon, E.; Pras, Ph.; Boudard, A.; Legrain, R.; Leray, S.; Terrien, Y.; Bouyer, P.; Brochard, F.; Duchazeaubeneix, J.C.; Durand, J.M.; Meigo, S.I.; Milleret, G.; Thun, J.; Whittal, D.M.; Wlazlo, W.; Lebrun, C.; Lecolley, J.F.; Lecolley, F.R.; Lefebvres, F.; Louvel, M.; Varignon, C.; Menard, S.; Stugge, L.; Hanappe, F.

    2000-01-01

    Angular distribution of spallation neutrons induced by protons (0.8, 1.2 and 1.6 GeV) and deuterons (0.8 and 1.6 GeV beams on various thin targets have been measured at SATURNE (CEA Saclay/France) with two complementary experimental techniques: the time-of-flight measurement with tagged incident protons for low energy neutrons (2-400 MeV) and the use of a hydrogen converter associated are analysed, interpreted and finally compared with theoretical previsions of simulation codes using the TIERCE system including the intranuclear cascade codes of BERTINI and CUGNON. (authors)

  9. Experimental study of the nucleon spin structure

    Energy Technology Data Exchange (ETDEWEB)

    Litmaath, M.F.

    1996-05-07

    After introducing the theoretical framework, which includes DIS, the Quark Parton Model (QPM) and QCD, we describe the implementation of the experiment. The SMC uses a beam of 190 GeV naturally polarized muons, scattering off nucleons in a large cryogenic target containing protons or deuterons that are polarized through Dynamic Nuclear Polarization (DNP). The target material is located in two cells in a row, with opposite polarizations. Every 5 hours the polarizations of both cells are reversed. The target polarization is measured by an NMR system. The polarization of the beam is measured in a polarimeter, located downstream of the main experimental setup. (orig.).

  10. Experimental study of the nucleon spin structure

    International Nuclear Information System (INIS)

    Litmaath, M.F.

    1996-01-01

    After introducing the theoretical framework, which includes DIS, the Quark Parton Model (QPM) and QCD, we describe the implementation of the experiment. The SMC uses a beam of 190 GeV naturally polarized muons, scattering off nucleons in a large cryogenic target containing protons or deuterons that are polarized through Dynamic Nuclear Polarization (DNP). The target material is located in two cells in a row, with opposite polarizations. Every 5 hours the polarizations of both cells are reversed. The target polarization is measured by an NMR system. The polarization of the beam is measured in a polarimeter, located downstream of the main experimental setup. (orig.)

  11. Normal Values for Heart Electrophysiology Parameters of Healthy Swine Determined on Electrophysiology Study.

    Science.gov (United States)

    Noszczyk-Nowak, Agnieszka; Cepiel, Alicja; Janiszewski, Adrian; Pasławski, Robert; Gajek, Jacek; Pasławska, Urszula; Nicpoń, Józef

    2016-01-01

    Swine are a well-recognized animal model for human cardiovascular diseases. Despite the widespread use of porcine model in experimental electrophysiology, still no reference values for intracardiac electrical activity and conduction parameters determined during an invasive electrophysiology study (EPS) have been developed in this species thus far. The aim of the study was to develop a set of normal values for intracardiac electrical activity and conduction parameters determined during an invasive EPS of swine. The study included 36 healthy domestic swine (24-40 kg body weight). EPS was performed under a general anesthesia with midazolam, propofol and isoflurane. The reference values for intracardiac electrical activity and conduction parameters were calculated as arithmetic means ± 2 standard deviations. The reference values were determined for AH, HV and PA intervals, interatrial conduction time at its own and imposed rhythm, sinus node recovery time (SNRT), corrected sinus node recovery time (CSNRT), anterograde and retrograde Wenckebach points, atrial, atrioventricular node and ventricular refractory periods. No significant correlations were found between body weight and heart rate of the examined pigs and their electrophysiological parameters. The hereby presented reference values can be helpful in comparing the results of various studies, as well as in more accurately estimating the values of electrophysiological parameters that can be expected in a given experiment.

  12. Experimental parameters differentially affect the humoral response of the cholera-toxin-based murine model of food allergy

    DEFF Research Database (Denmark)

    Kroghsbo, S.; Christensen, Hanne Risager; Frøkiær, Hanne

    2003-01-01

    Background: Recent studies have developed a murine model of IgE-mediated food allergy based on oral coadministration of antigen and cholera toxin (CT) to establish a maximal response for studying immunopathogenic mechanisms and immunotherapeutic strategies. However, for studying subtle...... interested in characterizing the individual effects of the parameters in the CT-based model: CT dose, antigen type and dose, and number of immunizations. Methods: BALB/c mice were orally sensitized weekly for 3 or 7 weeks with graded doses of CT and various food antigens (soy-trypsin inhibitor, ovalbumin...... of the antibody response depended on the type of antigen and number of immunizations. Conclusions: The critical parameters of the CT-based murine allergy model differentially control the intensity and kinetics of the developing immune response. Adjustment of these parameters could be a key tool for tailoring...

  13. Studying the noise parameters of thin-film silicon resistors

    International Nuclear Information System (INIS)

    Belogurov, S.V.; Gostilo, V.V.; Yurov, A.S.

    1986-01-01

    The results of studies on spectral density and energy noise equivalent of thin-film resistors on the base of amorphous silicon and KIM and KVM commercial high-ohmic resistors are presented. Dependence of the active part of impedance on frequency is shown to be the main source of redundant noise in resistors. Dependence of spectral density of noise voltage of current noises of silicon resistors on applied voltage is described by the formula S T =B V 2 /f 1.6 with the values B=(1.4-1.7)x10 -12 Hz 0.6 . As to noise parameters the silicon resistor is superior to commercial resistors

  14. Study of nuclear level density parameter and its temperature dependence

    International Nuclear Information System (INIS)

    Nasrabadi, M. N.; Behkami, A. N.

    2000-01-01

    The nuclear level density ρ is the basic ingredient required for theoretical studies of nuclear reaction and structure. It describes the statistical nuclear properties and is expressed as a function of various constants of motion such as number of particles, excitation energy and angular momentum. In this work the energy and spin dependence of nuclear level density will be presented and discussed. In addition the level density parameter α will be extracted from this level density information, and its temperature and mass dependence will be obtained

  15. Characterizing parameters of Jatropha curcas cell cultures for microgravity studies

    Science.gov (United States)

    Vendrame, Wagner A.; Pinares, Ania

    2013-06-01

    Jatropha (Jatropha curcas) is a tropical perennial species identified as a potential biofuel crop. The oil is of excellent quality and it has been successfully tested as biodiesel and in jet fuel mixes. However, studies on breeding and genetic improvement of jatropha are limited. Space offers a unique environment for experiments aiming at the assessment of mutations and differential gene expression of crops and in vitro cultures of plants are convenient for studies of genetic variation as affected by microgravity. However, before microgravity studies can be successfully performed, pre-flight experiments are necessary to characterize plant material and validate flight hardware environmental conditions. Such preliminary studies set the ground for subsequent spaceflight experiments. The objectives of this study were to compare the in vitro growth of cultures from three explant sources (cotyledon, leaf, and stem sections) of three jatropha accessions (Brazil, India, and Tanzania) outside and inside the petriGAP, a modified group activation pack (GAP) flight hardware to fit petri dishes. In vitro jatropha cell cultures were established in petri dishes containing a modified MS medium and maintained in a plant growth chamber at 25 ± 2 °C in the dark. Parameters evaluated were surface area of the explant tissue (A), fresh weight (FW), and dry weight (DW) for a period of 12 weeks. Growth was observed for cultures from all accessions at week 12, including subsequent plantlet regeneration. For all accessions differences in A, FW and DW were observed for inside vs. outside the PetriGAPs. Growth parameters were affected by accession (genotype), explant type, and environment. The type of explant influenced the type of cell growth and subsequent plantlet regeneration capacity. However, overall cell growth showed no abnormalities. The present study demonstrated that jatropha in vitro cell cultures are suitable for growth inside PetriGAPs for a period of 12 weeks. The parameters

  16. Experimental critical parameters of enriched uranium solution in annular tank geometries

    Energy Technology Data Exchange (ETDEWEB)

    Rothe, R.E.

    1996-04-01

    A total of 61 critical configurations are reported for experiments involving various combinations of annular tanks into which enriched uranium solution was pumped. These experiments were performed at two widely separated times in the 1980s under two programs at the Rocky Flats Plant`s Critical Mass Laboratory. The uranyl nitrate solution contained about 370 g of uranium per liter, but this concentration varied a little over the duration of the studies. The uranium was enriched to about 93% [sup 235]U. All tanks were typical of sizes commonly found in nuclear production plants. They were about 2 m tall and ranged in diameter from 0.6 m to 1.5 m. Annular thicknesses and conditions of neutron reflection, moderation, and absorption were such that criticality would be achieved with these dimensions. Only 13 of the entire set of 74 experiments proved to be subcritical when tanks were completely filled with solution. Single tanks of several radial thicknesses were studied as well as small line arrays (1 x 2 and 1 x 3) of annular tanks. Many systems were reflected on four sides and the bottom by concrete, but none were reflected from above. Many experiments also contained materials within and outside the annular regions that contained strong neutron absorbers. One program had such a thick external moderator/absorber combination that no reflector was used at all.

  17. Experimental critical parameters of enriched uranium solution in annular tank geometries

    International Nuclear Information System (INIS)

    Rothe, R.E.

    1996-04-01

    A total of 61 critical configurations are reported for experiments involving various combinations of annular tanks into which enriched uranium solution was pumped. These experiments were performed at two widely separated times in the 1980s under two programs at the Rocky Flats Plant's Critical Mass Laboratory. The uranyl nitrate solution contained about 370 g of uranium per liter, but this concentration varied a little over the duration of the studies. The uranium was enriched to about 93% [sup 235]U. All tanks were typical of sizes commonly found in nuclear production plants. They were about 2 m tall and ranged in diameter from 0.6 m to 1.5 m. Annular thicknesses and conditions of neutron reflection, moderation, and absorption were such that criticality would be achieved with these dimensions. Only 13 of the entire set of 74 experiments proved to be subcritical when tanks were completely filled with solution. Single tanks of several radial thicknesses were studied as well as small line arrays (1 x 2 and 1 x 3) of annular tanks. Many systems were reflected on four sides and the bottom by concrete, but none were reflected from above. Many experiments also contained materials within and outside the annular regions that contained strong neutron absorbers. One program had such a thick external moderator/absorber combination that no reflector was used at all

  18. Experimental Study of Hysteretic Steel Damper for Energy Dissipation Capacity

    Directory of Open Access Journals (Sweden)

    Daniel R. Teruna

    2015-01-01

    Full Text Available This study aims to evaluate energy absorption capacity of hysteretic steel damper for earthquake protection of structures. These types of steel dampers are fabricated from mild steel plate with different geometrical shapes on the side part, namely, straight, concave, and convex shapes. The performance of the proposed device was verified experimentally by a series of tests under increasing in-plane cyclic load. The overall test results indicated that the proposed steel dampers have similar hysteretic curves, but the specimen with convex-shaped side not only showed stable hysteretic behavior but also showed excellent energy dissipation capabilities and ductility factor. Furthermore, the load-deformation relation of these steel dampers can be decomposed into three parts, namely, skeleton curve, Bauschinger part, and elastic unloading part. The skeleton curve is commonly used to obtain the main parameters, which describe the behavior of steel damper, namely, yield strength, elastic stiffness, and postyield stiffness ratio. Moreover, the effective stiffness, effective damping ratio, cumulative plastic strain energy, and cumulative ductility factor were also derived from the results. Finally, an approximation trilinear hysteretic model was developed based on skeleton curve obtained from experimental results.

  19. Feasibility study of the AOSTA experimental campaign

    Directory of Open Access Journals (Sweden)

    Carta M.

    2016-01-01

    Full Text Available The reduction of the nuclear waste is one of the most important nuclear issues. The high radiotoxicity of the spent fuel is due to plutonium and some minor actinides (MAs such as neptunium, americium and curium, above all. One way to reduce their hazard is to destroy by fission MAs in appropriate nuclear reactors. To allow the MAs destruction an important effort have been done on the nuclear data due to the poor knowledge in this field. In the framework of one of the NEA Expert Group on Integral Experiments for Minor Actinide Management an analysis of the feasibility of MAs irradiation campaign in the TAPIRO fast research reactor is carried out. This paper provides preliminary results obtained by calculations modelling the irradiation, in different TAPIRO irradiation channels, of some CEA samples coming from the French experimental campaign OSMOSE, loaded with different contents of MAs, in order to access, through particular peak spectrometry, to their capture cross section. On the basis of neutron transport calculation results, obtained by both deterministic and Monte Carlo methods, an estimate of the irradiated samples counting levels from the AOSTA (Activation of OSMOSE Samples in TAPIRO experimental campaign is provided.

  20. Experimental thermochemical study of the monochloronitrobenzene isomers

    International Nuclear Information System (INIS)

    Ribeiro da Silva, Manuel A.V.; Lobo Ferreira, Ana I.M.C.; Moreno, Ana Rita G.

    2009-01-01

    The standard (p 0 = 0.1 MPa) molar enthalpies of formation of 2-, 3-, and 4-chloronitrobenzene isomers, in the crystalline state, at T = 298.15 K, were derived from the standard (p 0 = 0.1 MPa) massic energies of combustion, in oxygen, at T = 298.15 K, measured by rotating bomb combustion calorimetry. The standard molar enthalpies of sublimation of the isomers, at T = 298.15 K, were obtained by high temperature Calvet microcalorimetry. From the determined experimental data, the values of the gaseous standard (p 0 = 0.1 MPa) molar enthalpies of formation for the three monochloronitrobenzene isomers were derived. The gas-phase enthalpies of formation were also estimated by the empirical scheme developed by Cox showing that for meta- and para-chloronitrobenzene the estimated values are in close agreement with the experimental ones whereas, in the case of ortho-chloronitrobenzene it is shown that a different enthalpic interaction increment is needed, when the substituents in the adjacent carbon ring atoms are a chlorine atom and a nitro group

  1. A systematic experimental investigation of significant parameters affecting model tire hydroplaning

    Science.gov (United States)

    Wray, G. A.; Ehrlich, I. R.

    1973-01-01

    The results of a comprehensive parametric study of model and small pneumatic tires operating on a wet surface are presented. Hydroplaning inception (spin down) and rolling restoration (spin up) are discussed. Conclusions indicate that hydroplaning inception occurs at a speed significantly higher than the rolling restoration speed. Hydroplaning speed increases considerably with tread depth, surface roughness and tire inflation pressure of footprint pressure, and only moderately with increased load. Water film thickness affects spin down speed only slightly. Spin down speed varies inversely as approximately the one-sixth power of film thickness. Empirical equations relating tire inflation pressure, normal load, tire diameter and water film thickness have been generated for various tire tread and surface configurations.

  2. Parameter uncertainty in simulations of extreme precipitation and attribution studies.

    Science.gov (United States)

    Timmermans, B.; Collins, W. D.; O'Brien, T. A.; Risser, M. D.

    2017-12-01

    The attribution of extreme weather events, such as heavy rainfall, to anthropogenic influence involves the analysis of their probability in simulations of climate. The climate models used however, such as the Community Atmosphere Model (CAM), employ approximate physics that gives rise to "parameter uncertainty"—uncertainty about the most accurate or optimal values of numerical parameters within the model. In particular, approximate parameterisations for convective processes are well known to be influential in the simulation of precipitation extremes. Towards examining the impact of this source of uncertainty on attribution studies, we investigate the importance of components—through their associated tuning parameters—of parameterisations relating to deep and shallow convection, and cloud and aerosol microphysics in CAM. We hypothesise that as numerical resolution is increased the change in proportion of variance induced by perturbed parameters associated with the respective components is consistent with the decreasing applicability of the underlying hydrostatic assumptions. For example, that the relative influence of deep convection should diminish as resolution approaches that where convection can be resolved numerically ( 10 km). We quantify the relationship between the relative proportion of variance induced and numerical resolution by conducting computer experiments that examine precipitation extremes over the contiguous U.S. In order to mitigate the enormous computational burden of running ensembles of long climate simulations, we use variable-resolution CAM and employ both extreme value theory and surrogate modelling techniques ("emulators"). We discuss the implications of the relationship between parameterised convective processes and resolution both in the context of attribution studies and progression towards models that fully resolve convection.

  3. Benefits of belonging: experimental manipulation of social inclusion to enhance psychological and physiological health parameters.

    Science.gov (United States)

    Begen, Fiona M; Turner-Cobb, Julie M

    2015-01-01

    Acute changes in social belonging are important triggers for alterations in health and well-being, yet research has emphasised the negative effects of 'exclusion' at the expense of evaluating the potentially positive effects of 'inclusion'. This study examined the impact of acute belonging on physiological and psychological outcomes. A healthy population (N = 138) were randomly allocated to 'included' or 'excluded' conditions. Condition-dependent differences in pre/during-task heart rate and pre/post-task self-reports of negative/positive mood, and social self-esteem, were assessed. Included participants showed decreased heart rate and negative mood, and increased social self-esteem. No inclusion-related change in positive mood was shown. An increase in heart rate was observed in excluded participants though no changes in negative/positive mood or social self-esteem were shown. Shifts in social self-esteem acted as a mechanism through which inclusion/exclusion impacted upon negative and positive mood alterations. Results remained significant in presence of covariates (sex, global self-esteem, rumination and social anxiety). Findings suggest that acting to enhance belonging through 'inclusion' resulted in adaptive physiological and psychological outcomes. Neutral and potentially protective responses were observed in the immediate aftermath of 'exclusion'. Self-esteem served as one route through which these effects were transmitted.

  4. High Z neoclassical transport: Application and limitation of analytical formulae for modelling JET experimental parameters

    Science.gov (United States)

    Breton, S.; Casson, F. J.; Bourdelle, C.; Angioni, C.; Belli, E.; Camenen, Y.; Citrin, J.; Garbet, X.; Sarazin, Y.; Sertoli, M.; JET Contributors

    2018-01-01

    Heavy impurities, such as tungsten (W), can exhibit strongly poloidally asymmetric density profiles in rotating or radio frequency heated plasmas. In the metallic environment of JET, the poloidal asymmetry of tungsten enhances its neoclassical transport up to an order of magnitude, so that neoclassical convection dominates over turbulent transport in the core. Accounting for asymmetries in neoclassical transport is hence necessary in the integrated modeling framework. The neoclassical drift kinetic code, NEO [E. Belli and J. Candy, Plasma Phys. Controlled Fusion P50, 095010 (2008)], includes the impact of poloidal asymmetries on W transport. However, the computational cost required to run NEO slows down significantly integrated modeling. A previous analytical formulation to describe heavy impurity neoclassical transport in the presence of poloidal asymmetries in specific collisional regimes [C. Angioni and P. Helander, Plasma Phys. Controlled Fusion 56, 124001 (2014)] is compared in this work to numerical results from NEO. Within the domain of validity of the formula, the factor for reducing the temperature screening due to poloidal asymmetries had to be empirically adjusted. After adjustment, the modified formula can reproduce NEO results outside of its definition domain, with some limitations: When main ions are in the banana regime, the formula reproduces NEO results whatever the collisionality regime of impurities, provided that the poloidal asymmetry is not too large. However, for very strong poloidal asymmetries, agreement requires impurities in the Pfirsch-Schlüter regime. Within the JETTO integrated transport code, the analytical formula combined with the poloidally symmetric neoclassical code NCLASS [W. A. Houlberg et al., Phys. Plasmas 4, 3230 (1997)] predicts the same tungsten profile as NEO in certain cases, while saving a factor of one thousand in computer time, which can be useful in scoping studies. The parametric dependencies of the temperature

  5. Theoretical and experimental studies of elementary physics

    International Nuclear Information System (INIS)

    Bodek, A.; Ferbel, T.; Melissinos, A.C.; Olsen, S.; Slattery, P.; Tipton, P.; Das, A.; Hagen, C.R.; Rajeev, S.G.; Okubo, S.

    1992-01-01

    The experimental high energy physics program is directed toward the execution of experiments that probe the basic constituents of matter and the forces between them. These experiments are carried out at national and international accelerator facilities. At the current time, we are primarily concentrating on the following projects: Direct photon production in hadronic reactions (Fermilab E706); Production of hybrid mesons in the nuclear Coulomb field; The D-Zero experiment at the Tevatron collider; Deep inelastic neutrino- and electron-nucleon scattering at FNAL and SLAC; Nonlinear QED at critical field strengths at SLAC; The Experiments at KEK (AMY, 17keV neutrino); The CDF experiment at the Tevatron collider; and SSC-related detector R ampersand D on scintillating tile- and diamond-based calorimetry and microstrip tracking detectors

  6. Theoretical and experimental studies of elementary physics

    International Nuclear Information System (INIS)

    Bodek, A.; Ferbel, T.; Melissinos, A.C.; Olsen, S.; Slattery, P.; Tipton, P.; Das, A.; Hagen, C.R.; Rajeev, S.G.; Okubo, S.

    1992-05-01

    The experimental high energy physics program is directed toward the execution of experiments that probe the basic constituents of matter and the forces between them. These experiments are carried out at national and international accelerator facilities. At the current time, we are primarily concentrating on the following projects: Direct photon production in hadronic reactions; production of hybrid mesons in the nuclear Coulomb field; the D-Zero experiment at the Tevatron collider; deep inelastic neutrino- and electron-nucleon scattering at FNAL and SLAC; nonlinear QED at critical field strengths at SLAC; the experiments at KEK (AMY, 17keV neutrino); the CDF experiment at the Tevatron collider; and SSC-related detector R ampersand D on scintillating tile- and diamond-based calorimetry and microstrip tracking detectors

  7. Study of some parameters of the fibrinogen - fibrin transformation reaction

    International Nuclear Information System (INIS)

    Hollard, D.; Suscillon, M.; Marcille, G.; Rambaud, F.; Baloyan, M.

    1966-01-01

    The authors studied the action of some parameters on the reaction of transformation fibrinogen-fibrin. The five parameters studied are: the concentration of substratum: a certain quantity of enzyme determines an optimum quantity of fibrinogen; the concentration of enzyme: a certain quantity of substratum defines an optimum quantity of enzyme, beyond which the excess of enzyme is unable to act, the substratum being saturated by the enzyme; the concentration of Ca ions: between 0,07 and 0,10 mg of Ca by mg of fibrinogen, the reaction appears with a great speed. Between 0,02 and 0,40 mg of Ca by mg of fibrinogen the fibrin stabilisation is possible, the FSF can act only inside the definite bounds; the ph of the solution: the reaction of the transformation appears with its maximum intensity on physiological ph, the polymerisation is not possible on acid ph; the temperature has an effect which could not really be verified owing to the fact that the technical realisation is difficult. (author) [fr

  8. Study on Parameters Modeling of Wind Turbines Using SCADA Data

    Directory of Open Access Journals (Sweden)

    Yonglong YAN

    2014-08-01

    Full Text Available Taking the advantage of the current massive monitoring data from Supervisory Control and Data Acquisition (SCADA system of wind farm, it is of important significance for anomaly detection, early warning and fault diagnosis to build the data model of state parameters of wind turbines (WTs. The operational conditions and the relationships between the state parameters of wind turbines are complex. It is difficult to establish the model of state parameter accurately, and the modeling method of state parameters of wind turbines considering parameter selection is proposed. Firstly, by analyzing the characteristic of SCADA data, a reasonable range of data and monitoring parameters are chosen. Secondly, neural network algorithm is adapted, and the selection method of input parameters in the model is presented. Generator bearing temperature and cooling air temperature are regarded as target parameters, and the two models are built and input parameters of the models are selected, respectively. Finally, the parameter selection method in this paper and the method using genetic algorithm-partial least square (GA-PLS are analyzed comparatively, and the results show that the proposed methods are correct and effective. Furthermore, the modeling of two parameters illustrate that the method in this paper can applied to other state parameters of wind turbines.

  9. Clinical experimental stress studies: methods and assessment.

    Science.gov (United States)

    Bali, Anjana; Jaggi, Amteshwar Singh

    2015-01-01

    Stress is a state of threatened homeostasis during which a variety of adaptive processes are activated to produce physiological and behavioral changes. Stress induction methods are pivotal for understanding these physiological or pathophysiological changes in the body in response to stress. Furthermore, these methods are also important for the development of novel pharmacological agents for stress management. The well-described methods to induce stress in humans include the cold pressor test, Trier Social Stress Test, Montreal Imaging Stress Task, Maastricht Acute Stress Test, CO2 challenge test, Stroop test, Paced Auditory Serial Addition Task, noise stress, and Mannheim Multicomponent Stress Test. Stress assessment in humans is done by measuring biochemical markers such as cortisol, cortisol awakening response, dexamethasone suppression test, salivary α-amylase, plasma/urinary norepinephrine, norepinephrine spillover rate, and interleukins. Physiological and behavioral changes such as galvanic skin response, heart rate variability, pupil size, and muscle and/or skin sympathetic nerve activity (microneurography) and cardiovascular parameters such as heart rate, blood pressure, and self-reported anxiety are also monitored to assess stress response. This present review describes these commonly employed methods to induce stress in humans along with stress assessment methods.

  10. Studies on some biochemical parameters in viral hepatitis patients

    International Nuclear Information System (INIS)

    El-Sherbiny, E.M.

    2002-01-01

    The present investigation deals with studying liver amino transferases (ALT. AST). Cholesterol and triglycerides. As well as testosterone and protection hormones in blood of Egyptian men infected with hepatitis C virus.hepatitis B virus and mixed B and C viruses. These biochemical parameters were evaluated to be used in diagnosis and prognosis of viral hepatitis. Which considered the most important health problem in Egypt and developing countries. Biochemical analysis were performed using spectrophotometric and radioimmunoassay techniques. All data will be subjected to statistical analysis in order to detect the most suitable biochemical analysis that can be used as specific tests for early diagnosis of viral hepatitis and to detect the parameters that show abnormalities among the different groups of infected patients. The data revealed that AST and ALT levels were increased in all patient groups. Concerning the level of triglycerides, it was increased only in the group of mixed viral hepatitis B and C, while cholesterol showed non-significant changes in all viral hepatitis groups. The sex hormone testosterone was decreased in all infected patients while the prolactin level was increased only in case of patients infected with mixed B and C viruses. However, these abnormal values in such sex hormones play a serious role in male sterility

  11. Physics design and experimental study of tokamak divertor

    International Nuclear Information System (INIS)

    Yan Jiancheng; Gao Qingdi; Yan Longwen; Wang Mingxu; Deng Baiquan; Zhang Fu; Zhang Nianman; Ran Hong; Cheng Fayin; Tang Yiwu; Chen Xiaoping

    2007-06-01

    The divertor configuration of HL-2A tokamak is optimized, and the plasma performance in divertor is simulated with B2-code. The effects of collisionality on plasma-wall transition in the scrape-off layer of divertor are investigated, high performances of the divertor plasma in HL-2A are simulated, and a quasi- stationary RS operation mode is established with the plasma controlled by LHCD and NBI. HL-2A tokamak has been successfully operated in divertor configuration. The major parameters: plasma current I p =320 kA, toroidal field B t =2.2 T, plasma discharger duration T d =1580 ms ware achieved at the end of 2004. The preliminary experimental researches of advanced diverter have been carried out. Design studies of divertor target plate for high power density fusion reactor have been carried out, especially, the physical processes on the surface of flowing liquid lithium target plate. The exploration research of improving divertor ash removal efficiency and reducing tritium inventory resulting from applying the RF ponderomotive force potential is studied. The optimization structure design studies of FEB-E reactor divertor are performed. High flux thermal shock experiments were carried on tungsten and carbon based materials. Hot Isostatic Press (HIP) method was employed to bond tungsten to copper alloys. Electron beam simulated thermal fatigue tests were also carried out to W/Cu bondings. Thermal desorption and surface modification of He + implanted into tungsten have been studied. (authors)

  12. Extrapolated experimental critical parameters of unreflected and steel-reflected massive enriched uranium metal spherical and hemispherical assemblies

    International Nuclear Information System (INIS)

    Rothe, R.E.

    1997-12-01

    Sixty-nine critical configurations of up to 186 kg of uranium are reported from very early experiments (1960s) performed at the Rocky Flats Critical Mass Laboratory near Denver, Colorado. Enriched (93%) uranium metal spherical and hemispherical configurations were studied. All were thick-walled shells except for two solid hemispheres. Experiments were essentially unreflected; or they included central and/or external regions of mild steel. No liquids were involved. Critical parameters are derived from extrapolations beyond subcritical data. Extrapolations, rather than more precise interpolations between slightly supercritical and slightly subcritical configurations, were necessary because experiments involved manually assembled configurations. Many extrapolations were quite long; but the general lack of curvature in the subcritical region lends credibility to their validity. In addition to delayed critical parameters, a procedure is offered which might permit the determination of prompt critical parameters as well for the same cases. This conjectured procedure is not based on any strong physical arguments

  13. Economic principles in communication: an experimental study.

    Science.gov (United States)

    De Jaegher, Kris; Rosenkranz, Stephanie; Weitzel, Utz

    2014-12-21

    This paper experimentally investigates how economic principles affect communication. In a simple sender-receiver game with common interests over payoffs, the sender can send a signal without a pre-given meaning in an infrequent or frequent state of the world. When the signal is costly, several theories (focal point theory, the intuitive criterion, evolutionary game theory) predict an efficient separating equilibrium, where the signal is sent in the infrequent state of the world (also referred to as Horn׳s rule). To analyze whether Horn׳s rule applies, and if so, which theory best explains it, we develop and test variants of the sender-receiver game where the theories generate discriminatory hypotheses. In costly signaling variants, our participants follow Horn׳s rule most of the time, in a manner that is best explained by focal point theory. In costless signaling variants, evolutionary game theory best explains our results. Here participants coordinate significantly more (less) often on a separating equilibrium where the signal is sent in the frequent state if they are primed to associate the absence of a signal with the infrequent (frequent) state of the world. We also find indications that a similar priming effect applies to costly signals. Thus, while the frequency with which participants follow Horn׳s rule in costly signaling variants is best explained by Horn׳s rule, the priming effect shows that some of our participants׳ behavior is best explained by evolutionary game theory even when signals are costly. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Experimental study on secondary electron emission characteristics of Cu

    Science.gov (United States)

    Liu, Shenghua; Liu, Yudong; Wang, Pengcheng; Liu, Weibin; Pei, Guoxi; Zeng, Lei; Sun, Xiaoyang

    2018-02-01

    Secondary electron emission (SEE) of a surface is the origin of the multipacting effect which could seriously deteriorate beam quality and even perturb the normal operation of particle accelerators. Experimental measurements on secondary electron yield (SEY) for different materials and coatings have been developed in many accelerator laboratories. In fact, the SEY is just one parameter of secondary electron emission characteristics which include spatial and energy distribution of emitted electrons. A novel experimental apparatus was set up in China Spallation Neutron Source, and an innovative method was applied to obtain the whole characteristics of SEE. Taking Cu as the sample, secondary electron yield, its dependence on beam injection angle, and the spatial and energy distribution of secondary electrons were achieved with this measurement device. The method for spatial distribution measurement was first proposed and verified experimentally. This contribution also tries to give all the experimental results a reasonable theoretical analysis and explanation.

  15. Study of Operating Parameters for Accelerated Anode Degradation in SOFCs

    DEFF Research Database (Denmark)

    Ploner, Alexandra; Hagen, Anke; Hauch, Anne

    2017-01-01

    Solid oxide fuel cell (SOFC) applications require lifetimes of several years on the system level. A big challenge is to demonstrate such exceptionally long lifetimes in ongoing R&D projects. Accelerated or compressed testing are alternative methods to obtain this. Activities in this area have been...... carried out without arriving at a generally accepted methodology. This is mainly due to the complexity of degradation mechanisms on the single SOFC components as function of operating parameters. In this study, we present a detailed analysis of approx. 180 durability tests regarding degradation of single...... SOFC components as function of operating conditions. Electrochemical impedance data were collected on the fresh and long-term tested SOFCs and used to de-convolute the individual losses of single SOFC cell components – electrolyte, cathode and anode. The main findings include a time-dependent effect...

  16. An experimental study of praseodymium intermetallic compounds at low temperatures

    International Nuclear Information System (INIS)

    Greidanus, F.J.A.M.

    1982-01-01

    In this thesis the author studies the low temperature properties of praseodymium intermetallic compounds. In chapter 2 some of the techniques used for the experiments described in the subsequent chapters are discussed. A set-up to perform specific-heat experiments below 1 K and a technique for performing magnetic susceptibility measurments below 1 K, using a superconducting quantum interference device (SQUID) are described. Chapter 3 is devoted to the theory of interacting Pr 3+ ions. Both bilinear and biquadratic interactions are dealt with in a molecular-field approximation. It is shown that first as well as second-order phase transitions can occur, depending on the nature of the ground state, and on the ratio of magnetic to crystal-field interactions. In chapters 4, 5, 6 and 7 experimental results on the cubic Laves phase compounds PrRh 2 , PrIr 2 , PrPt 2 , PrRu 2 and PrNi 2 are presented. From inelastic neutron scattering experiments the crystalline electric field parameters of the above compounds are determined. In chapters 5 and 6 susceptibility, neutron-diffraction, hyperfine specific-heat, low-field magnetization, pulsed-field magnetization, specific-heat and resistivity measurements are presented. In chapter 7 the specific heat and differential susceptibility of PrNi 2 below 1 K are studied. Finally, in chapter 8 praseodymium intermetallic compounds with low-symmetry singlet ground states, and cubic compounds with magnetic doublet ground states are studied. (Auth.)

  17. Experimental study of nylon fibre reinforced RC beams

    International Nuclear Information System (INIS)

    Ansari, A.A.; Jokhio, S.; Qazi, Attiq-ur-Rehman

    2002-01-01

    Six concrete beams reinforced with Nylon fibre strands placed in tensile zone as an alternative of steel bars have been tested. Fibre of 1.2 mm dia was used and 10 pieces were twisted together to form the strand; the number of turns being a parameter of study. This was done in order to over come the problem of bond, because the surface of fibre is very smooth and slippery. Two strands were used in each beam and in order to eliminate possibility of premature failure due to bond, specially designed End-Steel Anchorages were also tried. All the beams were 1000 mm long and 50 x 100 mm in cross section with an affective span of 900 mm. The tensile behaviors as well as moduli of the fibre itself were also determined. No shear reinforcement was used. The results are encourage and comparative financial study shows that this material holds promise for future use. However, more experimental study is needed. (author)

  18. Does Cigarette Smoking Affect Seminal Fluid Parameters? A Comparative Study

    Directory of Open Access Journals (Sweden)

    Zakarya Bani Meri

    2013-01-01

    Full Text Available Objective: To study the effect of cigarette smoking on seminal fluid parameters, namely; volume, sperm concentration, and motility, as well as morphology, leukocyte infiltration, among males complaining of infertility.Methods: Between August 2010 and July 2011, seminal fluid analysis was done for 1438 males who are partners of couples who visited the infertility clinic at Prince Rashid Ben Al Hassan Hospital (PRH for infertility. The men who fit the inclusion criteria (n=960 were classified into two groups: group a (non-smokers; n=564 and group B (smokers; n=396, which represents 41.25% of the study group. Seminal fluid was collected using masturbation after 3-5 days of abstinence then analyzed for volume, sperm count, sperm concentration, motility and morphology. In order to analyze whether the number of cigarettes smoked per day has an effect on the spermatogram; the smoking men were divided into two subgroups: the heavy smokers (n=266 and non-heavy smokers (n=130.Results: A total of 960 adult males were enrolled. Their age ranged between 21 and 76 years, 564 were non-smokers with mean age of 36. 45±6.27 (Mean±SD. Three-hundred-and-ninety-six were smokers with a mean age of 34.35±4.25 (Mean±SD. There was a significant effect of smoking on the motility of sperms and the ratios of abnormality (p<0.005. Concentration appeared not to be affected by smoking. Furthermore, the group of heavy smokers were found to have lower sperm concentrations and a higher percentage of abnormal sperms compared to the non-heavy smokers.Conclusion: Cigarette smoking has a deleterious effect on some of the seminal fluid parameters (motility, morphology and leukocyte count which in turn may result in male subfertility.

  19. Experimental study of oxidative DNA damage

    DEFF Research Database (Denmark)

    Loft, Steffen; Deng, Xin-Sheng; Tuo, Jingsheng

    1998-01-01

    Animal experiments allow the study of oxidative DNA damage in target organs and the elucidation of dose-response relationships of carcinogenic and other harmful chemicals and conditions as well as the study of interactions of several factors. So far the effects of more than 50 different chemical ...

  20. Lithium hydride hydrolysis: experimental and kinetic study

    International Nuclear Information System (INIS)

    Charton, S.; Maupoix, C.; Brevet, A.; Delaunay, F.; Heintz, O.; Saviot, L.

    2006-01-01

    In this work has been studied the contribution of various analyses techniques in the framework, on the one hand of revealing the mechanisms implied in lithium hydride hydrolysis, and on the other hand of studying the kinetics of hydrogen production. Among the methods recently investigated, Raman spectroscopy, XPS and SIMS seem to be particularly attractive. (O.M.)

  1. Theoretical & Experimental Studies of Elementary Particles

    Energy Technology Data Exchange (ETDEWEB)

    McFarland, Kevin [Univ. of Rochester, NY (United States)

    2012-10-04

    Abstract High energy physics has been one of the signature research programs at the University of Rochester for over 60 years. The group has made leading contributions to experimental discoveries at accelerators and in cosmic rays and has played major roles in developing the theoretical framework that gives us our ``standard model'' of fundamental interactions today. This award from the Department of Energy funded a major portion of that research for more than 20 years. During this time, highlights of the supported work included the discovery of the top quark at the Fermilab Tevatron, the completion of a broad program of physics measurements that verified the electroweak unified theory, the measurement of three generations of neutrino flavor oscillations, and the first observation of a ``Higgs like'' boson at the Large Hadron Collider. The work has resulted in more than 2000 publications over the period of the grant. The principal investigators supported on this grant have been recognized as leaders in the field of elementary particle physics by their peers through numerous awards and leadership positions. Most notable among them is the APS W.K.H. Panofsky Prize awarded to Arie Bodek in 2004, the J.J. Sakurai Prizes awarded to Susumu Okubo and C. Richard Hagen in 2005 and 2010, respectively, the Wigner medal awarded to Susumu Okubo in 2006, and five principal investigators (Das, Demina, McFarland, Orr, Tipton) who received Department of Energy Outstanding Junior Investigator awards during the period of this grant. The University of Rochester Department of Physics and Astronomy, which houses the research group, provides primary salary support for the faculty and has waived most tuition costs for graduate students during the period of this grant. The group also benefits significantly from technical support and infrastructure available at the University which supports the work. The research work of the group has provided educational opportunities

  2. Experimental studies of flooding in nearly horizontal pipes

    International Nuclear Information System (INIS)

    Choi, Ki Yong

    1993-02-01

    To investigate the flooding phenomenon in nearly horizontal pipes the experimental studies are performed in the facility with the length of 2160mm, with three different inner diameters of 40mm, 60mm, and 70mm, and with the various inclination angles. Air and water approximately at room temperature and at atmospheric pressure are used as test fluids. The local void factions are measured by the three conductance probes located at the inlet, middle, and exit of water flow, respectively. Two mechanisms governing the transition to flooding are proposed. The effects of pipe end geometry, pipe diameter, and inclination angle are investigated and the comparisons with the slug formation models are conducted. It is found in this study that the transition to flooding is originated from two mechanisms i.e. 'wave instability' and 'high head flooding', and two regions (sub-critical and super-critical) coexist if the air flow increases up to a criticalvalue. It is observed that large roll waves are grown to the critical amplitude in the sub-critical region, does not show any dustive growth phenomenon. When the void fraction in the sub-critical region is used as the parameter for the flooding criterion, Ishii's slug formation model predicts the data without systematid errors. On the other hand, when the voide fraction in the super-critical region is selected as the parameter, Taitel's slug formation model best fitsthe data. Data obtained in the condition of high head flooding are not in good agreement with the results predicted by the slug formation models. Also, the transition criterion to the onset of flooding is very sensitive to the inclination angle, and the effect of pipe end geometry on the onset of flooding is negligible

  3. Theoretical and experimental studies for optimization of PCRV top closures

    International Nuclear Information System (INIS)

    Ottosen, N.S.; Andersen, S.I.

    1975-01-01

    The results from the remaining part of the parameter study and the preparations for the verification of an optimized design are presented. Three models have been made in the same scale and with the same depth to span ratio α as the low LM-3 model from the first investigation, i.e. α=0.35. The model LM-5 was provided with reinforcement in the tensile zone, the upper part of the closure. This reinforcement did not influence the stresses and strains in the load carrying concrete, and the dome failed at the same pressure as in the unreinforced model LM-3. However, the closure did not disintegrate, but failed due to large overall deformations causing seal leakage. In the model LM-6, the inverted dome, which is formed at higher loads as demonstrated in LM-3, was reinforced perpendicular to the supposed middle surface. This reinforcement proved to be effective, giving the dome a higher ultimate load capacity. The LM-6 test stopped due to a circumferential crack in the flange. Finally, the unreinforced LM-7 closure was tested to failure. Apart from minor changes in the flange, LM-7 was identical to LM-3 except for the excavated upper part of the concrete, which in LM-3 formed the heavily cracked tensile zone. The ultimate load and the failure mode observed for this closure were the same as for the LM-3. The experimental results are compared to finite element calculations, in which plasticity and cracking of the concrete are taken into account, and the influence of different material models for the concrete is investigated. A unique failure criterion, which includes failure of the concrete for both tensile and compressive stresses in the same mathematical expression, is proposed. Based on the results obtained from the parameter study, a new closure design is proposed, which is optimized with respect to the requirements at service conditions and ultimate load

  4. Multi-parameter geometrical scaledown study for energy optimization of MTJ and related spintronics nanodevices

    Science.gov (United States)

    Farhat, I. A. H.; Alpha, C.; Gale, E.; Atia, D. Y.; Stein, A.; Isakovic, A. F.

    The scaledown of magnetic tunnel junctions (MTJ) and related nanoscale spintronics devices poses unique challenges for energy optimization of their performance. We demonstrate the dependence of the switching current on the scaledown variable, while considering the influence of geometric parameters of MTJ, such as the free layer thickness, tfree, lateral size of the MTJ, w, and the anisotropy parameter of the MTJ. At the same time, we point out which values of the saturation magnetization, Ms, and anisotropy field, Hk, can lead to lowering the switching current and overall decrease of the energy needed to operate an MTJ. It is demonstrated that scaledown via decreasing the lateral size of the MTJ, while allowing some other parameters to be unconstrained, can improve energy performance by a measurable factor, shown to be the function of both geometric and physical parameters above. Given the complex interdependencies among both families of parameters, we developed a particle swarm optimization (PSO) algorithm that can simultaneously lower energy of operation and the switching current density. Results we obtained in scaledown study and via PSO optimization are compared to experimental results. Support by Mubadala-SRC 2012-VJ-2335 is acknowledged, as are staff at Cornell-CNF and BNL-CFN.

  5. Experimental Study on Gastric Juice Secretion by ...

    African Journals Online (AJOL)

    管理平台

    2012-05-29

    May 29, 2012 ... Study on stomach physiological functions by ... mechanism of regulating gastric electrical activity and gastric juice secretion might become true by the .... samples was used in comparism among these different groups.

  6. Experimental approaches for studying non-equilibrium atmospheric plasma jets

    Energy Technology Data Exchange (ETDEWEB)

    Shashurin, A., E-mail: ashashur@purdue.edu [School of Aeronautics & Astronautics, Purdue University, West Lafayette, Indiana 47907 (United States); Keidar, M. [Department of Mechanical and Aerospace Engineering, The George Washington University, Washington, District of Columbia 20052 (United States)

    2015-12-15

    This work reviews recent research efforts undertaken in the area non-equilibrium atmospheric plasma jets with special focus on experimental approaches. Physics of small non-equilibrium atmospheric plasma jets operating in kHz frequency range at powers around few Watts will be analyzed, including mechanism of breakdown, process of ionization front propagation, electrical coupling of the ionization front with the discharge electrodes, distributions of excited and ionized species, discharge current spreading, transient dynamics of various plasma parameters, etc. Experimental diagnostic approaches utilized in the field will be considered, including Rayleigh microwave scattering, Thomson laser scattering, electrostatic streamer scatterers, optical emission spectroscopy, fast photographing, etc.

  7. THE STUDY OF THE MAIN PARAMETERS QUALITY OF BUFFALO MILK

    Directory of Open Access Journals (Sweden)

    AURELIA PECE

    2010-02-01

    Full Text Available Researches were conducted on a biologic material, a buffalo livestock, in different lactating stages and their physico-chemical parameters were determined: fat, protein, lactose, unfat dry substance, density, pH, temperature. Regarding the variation of these components, researches conducted emphasized differences determined by those conditions specific to reference seasons. Individual analysis on the buffalo livestock in the study, emphasized significant differences: fat 8.59-9.36%, protein 5.16-5.31% respective of lactation. Microbiologic determinations mainly envisioned: the number of somatic cells (NSC, number of total germs (NTG Positive Coagulanzo Stafilococii, Listeria, Salmonella, determinations which lay at the basis of the assessment of buffalo milk quality. The positive Coagulanzo stafilococus was absent, excepting sample number 15 (2 germs/ml and sample number 22 (4 germs/ml; Salmonella was absent. Regarding the total number of germs: values between 1.0-1.8 germs/ml were obtained. The detection of this microbiologic parameter in the composition of buffalo milk provides information regarding the hygienic conditions of their production and handling. Correlations between the number of somatic cells, milk production and composition are employed in dairy buffalo farms, in order to assess losses caused by mastitis and the implementing of certain measures for the control of these diseases. On the other hand, correlations between the number of somatic cells and milk composition prove useful in establishing milk processing behaviour, as the practice of setting milk-raw matter prices according to the number of somatic cells in the milk is becoming increasingly more frequent in developed countries.

  8. Experimental studies of actinides in molten salts

    International Nuclear Information System (INIS)

    Reavis, J.G.

    1985-06-01

    This review stresses techniques used in studies of molten salts containing multigram amounts of actinides exhibiting intense alpha activity but little or no penetrating gamma radiation. The preponderance of studies have used halides because oxygen-containing actinide compounds (other than oxides) are generally unstable at high temperatures. Topics discussed here include special enclosures, materials problems, preparation and purification of actinide elements and compounds, and measurements of various properties of the molten volts. Property measurements discussed are phase relationships, vapor pressure, density, viscosity, absorption spectra, electromotive force, and conductance. 188 refs., 17 figs., 6 tabs

  9. Experimental studies of actinides in molten salts

    Energy Technology Data Exchange (ETDEWEB)

    Reavis, J.G.

    1985-06-01

    This review stresses techniques used in studies of molten salts containing multigram amounts of actinides exhibiting intense alpha activity but little or no penetrating gamma radiation. The preponderance of studies have used halides because oxygen-containing actinide compounds (other than oxides) are generally unstable at high temperatures. Topics discussed here include special enclosures, materials problems, preparation and purification of actinide elements and compounds, and measurements of various properties of the molten volts. Property measurements discussed are phase relationships, vapor pressure, density, viscosity, absorption spectra, electromotive force, and conductance. 188 refs., 17 figs., 6 tabs.

  10. Analysis and experimental study on hydraulic balance characteristics in density lock

    International Nuclear Information System (INIS)

    Gu Haifeng; Yan Changqi; Sun Furong

    2009-01-01

    Through the simplified theoretical model, the hydraulic balance condition which should be met in the density lock is obtained, when reactor operates normally and density lock is closed. The main parameters influencing this condition are analyzed, and the results show that the hydraulic balance in the density lock is characterized with self-stability in a certain range. Meantime, a simulating experimental loop is built and experimental verification on the self-stability characteristic is done. Moreover, experimental study is done on the conditions of flow change of work fluids in the primary circuit in the process of stable operations. The experimental results show that the hydraulic balance in the density lock can recovered quickly, depending on the self-stability characteristic without influences on the sealing performance of density lock and normal operation of reactor, after the change of operation parameters breaks the hydraulic balance. (authors)

  11. Optimization of Experimental Conditions of the Pulsed Current GTAW Parameters for Mechanical Properties of SDSS UNS S32760 Welds Based on the Taguchi Design Method

    Science.gov (United States)

    Yousefieh, M.; Shamanian, M.; Saatchi, A.

    2012-09-01

    Taguchi design method with L9 orthogonal array was implemented to optimize the pulsed current gas tungsten arc welding parameters for the hardness and the toughness of super duplex stainless steel (SDSS, UNS S32760) welds. In this regard, the hardness and the toughness were considered as performance characteristics. Pulse current, background current, % on time, and pulse frequency were chosen as main parameters. Each parameter was varied at three different levels. As a result of pooled analysis of variance, the pulse current is found to be the most significant factor for both the hardness and the toughness of SDSS welds by percentage contribution of 71.81 for hardness and 78.18 for toughness. The % on time (21.99%) and the background current (17.81%) had also the next most significant effect on the hardness and the toughness, respectively. The optimum conditions within the selected parameter values for hardness were found as the first level of pulse current (100 A), third level of background current (70 A), first level of % on time (40%), and first level of pulse frequency (1 Hz), while they were found as the second level of pulse current (120 A), second level of background current (60 A), second level of % on time (60%), and third level of pulse frequency (5 Hz) for toughness. The Taguchi method was found to be a promising tool to obtain the optimum conditions for such studies. Finally, in order to verify experimental results, confirmation tests were carried out at optimum working conditions. Under these conditions, there were good agreements between the predicted and the experimental results for the both hardness and toughness.

  12. Litigation and audit quality; two experimental studies

    NARCIS (Netherlands)

    Dijk, M. van

    1998-01-01

    This study examines the effect of litigation risk on auditors' willingness to yield to management pressure and to omit audit steps of the audit program in case of budget pressure. The results show that litigation risk has a significant impact on audit quality.

  13. Time to Criterion: An Experimental Study.

    Science.gov (United States)

    Anderson, Lorin W.

    The purpose of the study was to investigate the magnitude of individual differences in time-to-criterion and the stability of these differences. Time-to-criterion was defined in two ways: the amount of elapsed time required to attain the criterion level and the amount of on-task time required to attain the criterion level. Ninety students were…

  14. Experimental and theoretical study of cascade solar stills in Iran

    International Nuclear Information System (INIS)

    Tabrizi, F.F.; Sharak, A.Z.

    2009-01-01

    Due to low annual rainfall, most of Iran is dominated by arid and semi-arid areas. The solar radiation intensity is extremely high in most of the country. The need to produce fresh water from brackish water is considerably high, especially in dry regions. Desalination of brackish water may become a competitive potential water resource to meet potable water demand, and as the price of oil goes higher, using solar energy for water desalinisation becomes more economical. This paper presented a study that involved mathematical modeling of the first solar still in Iran. The cumulative fresh water production and water temperature were calculated as a function of time. The obtained results were verified by one month daily-based experimental data. The paper also provided background information on the Koshk village, situated in the south part of Iran near Badar Abbas city. Various investigations regarding meteorological conditions, economical considerations, and technical and operational appropriateness demonstrated that the cascade solar still is suitable for desalination of brackish water. 100 solar stills were installed at the site to provide potable water for a nearby village. It was concluded that the model could be used to simulate and optimize the effective design parameters in future studies. 6 refs., 7 figs

  15. Experimental Study of Flow in a Bifurcation

    Science.gov (United States)

    Fresconi, Frank; Prasad, Ajay

    2003-11-01

    An instability known as the Dean vortex occurs in curved pipes with a longitudinal pressure gradient. A similar effect is manifest in the flow in a converging or diverging bifurcation, such as those found in the human respiratory airways. The goal of this study is to characterize secondary flows in a bifurcation. Particle image velocimetry (PIV) and laser-induced fluorescence (LIF) experiments were performed in a clear, plastic model. Results show the strength and migration of secondary vortices. Primary velocity features are also presented along with dispersion patterns from dye visualization. Unsteadiness, associated with a hairpin vortex, was also found at higher Re. This work can be used to assess the dispersion of particles in the lung. Medical delivery systems and pollution effect studies would profit from such an understanding.

  16. studies on the correlation of some aggregate parameters in the ...

    African Journals Online (AJOL)

    BARTH EKWUEME

    simulations for problem solving and forecasting environmental conditions .... METHODS. Parameters: The water quality parameters examined were, Turbidity, Total Dissolved Solids (TDS),. Chemical Oxygen Demand (COD), 5-day Biochemical. Oxygen Demand ..... Vogel's Textbook of Quantitative. Chemical Analysis 6th ed ...

  17. Experimental investigations on the effect of process parameters with the use of minimum quantity solid lubrication in turning

    Science.gov (United States)

    Makhesana, Mayur A.; Patel, K. M.; Mawandiya, B. K.

    2018-04-01

    Turning process is a very basic process in any field of mechanical application. During turning process, most of the energy is converted into heat because of the friction between work piece and tool. Heat generation can affect the surface quality of the work piece and tool life. To reduce the heat generation, Conventional Lubrication process is used in most of the industry. Minimum quantity lubrication has been an effective alternative to improve the performance of machining process. In this present work, effort has been made to study the effect of various process parameters on the surface roughness and power consumption during turning of EN8 steel material. Result revealed the effect of depth of cut and feed on the obtained surface roughness value. Further the effect of solid lubricant has been also studied and optimization of process parameters is also done for the turning process.

  18. Experimental aspect of solid-state nuclear magnetic resonance studies of biomaterials such as bones.

    Science.gov (United States)

    Singh, Chandan; Rai, Ratan Kumar; Sinha, Neeraj

    2013-01-01

    Solid-state nuclear magnetic resonance (SSNMR) spectroscopy is increasingly becoming a popular technique to probe micro-structural details of biomaterial such as bone with pico-meter resolution. Due to high-resolution structural details probed by SSNMR methods, handling of bone samples and experimental protocol are very crucial aspects of study. We present here first report of the effect of various experimental protocols and handling methods of bone samples on measured SSNMR parameters. Various popular SSNMR experiments were performed on intact cortical bone sample collected from fresh animal, immediately after removal from animal systems, and results were compared with bone samples preserved in different conditions. We find that the best experimental conditions for SSNMR parameters of bones correspond to preservation at -20 °C and in 70% ethanol solution. Various other SSNMR parameters were compared corresponding to different experimental conditions. Our study has helped in finding best experimental protocol for SSNMR studies of bone. This study will be of further help in the application of SSNMR studies on large bone disease related animal model systems for statistically significant results. © 2013 Elsevier Inc. All rights reserved.

  19. Systematic parameter study of dynamo bifurcations in geodynamo simulations

    Science.gov (United States)

    Petitdemange, Ludovic

    2018-04-01

    We investigate the nature of the dynamo bifurcation in a configuration applicable to the Earth's liquid outer core, i.e. in a rotating spherical shell with thermally driven motions with no-slip boundaries. Unlike in previous studies on dynamo bifurcations, the control parameters have been varied significantly in order to deduce general tendencies. Numerical studies on the stability domain of dipolar magnetic fields found a dichotomy between non-reversing dipole-dominated dynamos and the reversing non-dipole-dominated multipolar solutions. We show that, by considering weak initial fields, the above transition disappears and is replaced by a region of bistability for which dipolar and multipolar dynamos coexist. Such a result was also observed in models with free-slip boundaries in which the geostrophic zonal flow can develop and participate to the dynamo mechanism for non-dipolar fields. We show that a similar process develops in no-slip models when viscous effects are reduced sufficiently. The following three regimes are distinguished: (i) Close to the onset of convection (Rac) with only the most critical convective mode (wave number) being present, dynamos set in supercritically in the Ekman number regime explored here and are dipole-dominated. Larger critical magnetic Reynolds numbers indicate that they are particularly inefficient. (ii) in the range 3 10) , the relative importance of zonal flows increases with Ra in non-magnetic models. The field topology depends on the magnitude of the initial magnetic field. The dipolar branch has a subcritical behavior whereas the multipolar branch has a supercritical behavior. By approaching more realistic parameters, the extension of this bistable regime increases. A hysteretic behavior questions the common interpretation for geomagnetic reversals. Far above the dynamo threshold (by increasing the magnetic Prandtl number), Lorentz forces contribute to the first order force balance, as predicted for planetary dynamos. When

  20. Experimental study on combination of chemotherapy and radiotherapy

    International Nuclear Information System (INIS)

    Tanaka, Juichi

    1986-01-01

    Recently, by applying multidrug therapy using cisplatin and bleomycin to the treatment of head and neck cancer, the response rate of chemotherapy has been markedly increased and thus, chemotherapy has taken an important part in the treatment of head and neck cancer. In this paper a clinical application of chemotherapy in combination with radiotherapy was evaluated from the point of the cure rate and also preservation of the structures and the functions of the head and neck region. In order to test the advantage or usefulness of initial chemotherapy followed by radiotherapy (= pre-radiation chemotherapy), the experimental study on combination of chemotherapy and radiotherapy was designed by using ICR mice and Ehrlich solid carcinoma. Cisplatin and peplomycin, a newly developed derivative of bleomycin, were used as chemotherapeutic agents. Tumor growth delay rate was chosen as a parameter to indicate the effectiveness. Results obtained are as follows. 1. Combination chemotherapy of cisplatin and peplomycin was more effective than each single agent on Ehrlich solid carcinoma. Synergistic effect was obtained by higher dose. So, the combination of cisplatin and peplomycin was proved to be eligible for pre-radiation chemotherapy. 2. Synergistic effect of chemotherapy and radiotherapy was observed when chemotherapy was used prior to radiotherapy on Ehrlich solid carcinoma. 3. Even their additional effect was not recognized when radiotherapy preceded to chemotherapy on Ehrlich solid carcinoma. 4. No severe toxic effect was seen in the mice. The experimental results made it clear that pre-radiation chemotherapy is beneficial to the treatment of head and neck cancer. (author)

  1. Research on Hygiene Based on Fieldwork and Experimental Studies.

    Science.gov (United States)

    Yajima, Ichiro

    2017-01-01

    Several experimental studies on hygiene have recently been performed and fieldwork studies are also important and essential tools. However, the implementation of experimental studies is insufficient compared with that of fieldwork studies on hygiene. Here, we show our well-balanced implementation of both fieldwork and experimental studies of toxic-element-mediated diseases including skin cancer and hearing loss. Since the pollution of drinking well water by toxic elements induces various diseases including skin cancer, we performed both fieldwork and experimental studies to determine the levels of toxic elements and the mechanisms behind the development of toxic-element-related diseases and to develop a novel remediation system. Our fieldwork studies in several countries including Bangladesh, Vietnam and Malaysia demonstrated that drinking well water was polluted with high concentrations of several toxic elements including arsenic, barium, iron and manganese. Our experimental studies using the data from our fieldwork studies demonstrated that these toxic elements caused skin cancer and hearing loss. Further experimental studies resulted in the development of a novel remediation system that adsorbs toxic elements from polluted drinking water. A well-balanced implementation of both fieldwork and experimental studies is important for the prediction, prevention and therapy of toxic-element-mediated diseases.

  2. The Experimental Study to Support IVR Strategy

    International Nuclear Information System (INIS)

    Ma, L.; Lu, W.; Hu, T.

    2015-01-01

    For alleviating the severe accident damage in nuclear power plant, In-vessel retention (IVR) is used on the severe accident management strategy in light water reactor. The criterion of IVR effectiveness is the safety margin, the value that between the melt pool heat flux and the critical heat flux on the lower head, matching the design requirements. For enhance the safety margin, the melt pool heat flux and the critical heat flux should be investigated. In the molten pool, the heat transfer behavior of metal layer is the focus problem because of the thermal focus effect. Therefore, the HELM was built to study the heat transfer correlations under the IVR conditions. The Globe–Dropkin correlation and Chu-Churchill correlation has been widely used to calculate the heat flux in the metal layer. However, the Rayleigh number (Ra) for the developed Power Plant has been shown to exceed the valid range for the G–D correlation. At the same time, other studies have shown that most correlations are far from the G–D correlation. Therefore, HELM verified the G–D correlations under the high Ra condition. The relationship between axial and radial heat transfer in the metal layer will also been studied. The behaviors of CHF varying with angular positions and the concentrations of coolant chemistry are investigated by the FIRM facility. FIRM is built to embody some key factors that influence the CHF: the heater block is 30o arc of circle with full-scale radius, and is made of the copper block covered by a thin carbon steel layer. The test section can be positioned in three tilted angles. Also, the effect of coolant chemistry will be examined by the mixed solution of water, deionized water, boric acid and tri-sodium phosphate. (author)

  3. Experimental study of isovector spin sum rules

    International Nuclear Information System (INIS)

    Alexandre Deur; Peter Bosted; Volker Burkert; Donald Crabb; Kahanawita Dharmawardane; Gail Dodge; Tony Forest; Keith Griffioen; Sebastian Kuhn; Ralph Minehart; Yelena Prok

    2008-01-01

    We present the Bjorken integral extracted from Jefferson Lab experiment EG1b for 0.05 2 . The integral is fit to extract the twist-4 element f 2 p-n which is large and negative. Systematic studies of this higher twist analysis establish its legitimacy at Q 2 around 1 GeV 2 . We also extracted the isovector part of the generalized forward spin polarizability γ 0 . Although this quantity provides a robust test of Chiral Perturbation Theory, our data disagree with the calculations

  4. Experimental study of relative, turbulent diffusion

    DEFF Research Database (Denmark)

    Mann, J.; Ott, Søren; Andersen, J.S.

    1999-01-01

    The purpose is to study relative turbulent diffusion under controlled, reproducible conditions in the laboratory in order to estimate the constant C in Richardson-Obukhov's law. We get C #approx# 0.4 -- 0.6. We furthermore measure the distance-neighbourfunction, which is the probability density...... system with two computers each equipped with a frame grabber card. In the search for the best experimentalmethods we have revised the concept of local homogeneity and derived a law for the velocity--acceleration structure function. A second by-product of this effort is a relatively simple derivation...

  5. Experimental and modelling studies of infiltration

    International Nuclear Information System (INIS)

    Giudici, M.

    2004-01-01

    This presentation describes a study of infiltration in the unsaturated soil with the objective of estimating the recharge to a phreatic aquifer. The study area is at the border of the city of Milan (Northern Italy), which draws water for both domestic and industrial purposes from ground water resources located beneath the urban area. The rate of water pumping from the aquifer system has been varying during the XX century, depending upon the number of inhabitants and the development of industrial activities. This caused variations with time of the depth of the water table below the ground surface and in turn some emergencies: the two most prominent episodes correspond to the middle '70s, when the water table in the city centre was about 30 m below the undisturbed natural conditions, and to the last decade, when the water table has raised at a rate of approximately 1 m/year and caused infiltrations in deep constructions (garages and building foundations, the underground railways, etc.). We have developed four ground water flow models at different scales, which share some characteristics: they are based on quasi-3D approximation (horizontal flow in the aquifers and vertical flow in the aquitards), conservative finite-differences schemes for regular grid with square cells in the horizontal plane and are implemented with proprietary computer codes. Among the problems that were studied for the development of these models, I recall some numerical problems, related to the behaviour of the phreatic aquifer under conditions of strong exploitation. Model calibration and validation for ModMil has been performed with a two-stage process, i.e., using some of the available data for model calibration and the remaining data for model validation. The application of geophysical exploration techniques, in particular seismic and geo-electrical prospecting, has been very useful to complete the data and information on the hydro-geological structure obtained from stratigraphic logs

  6. Experimental study of isovector spin sum rules

    International Nuclear Information System (INIS)

    Deur, A.; Bosted, P.; Burkert, V.; Crabb, D.; Minehart, R.; Prok, Y.; Dharmawardane, V.; Dodge, G. E.; Kuhn, S. E.; Forest, T. A.; Griffioen, K. A.

    2008-01-01

    We present the Bjorken integral extracted from Jefferson Lab experiment EG1b for 0.05 2 2 . The integral is fit to extract the twist-4 element f 2 p-n which appears to be relatively large and negative. Systematic studies of this higher twist analysis establish its legitimacy at Q 2 around 1 GeV 2 . We also performed an isospin decomposition of the generalized forward spin polarizability γ 0 . Although its isovector part provides a reliable test of the calculation techniques of chiral perturbation theory, our data disagree with the calculations.

  7. Study of Parameters that Determine Railway Line Capacity

    Directory of Open Access Journals (Sweden)

    Josip Kukec

    2005-07-01

    Full Text Available In this work the study focuses on:- determining the elements required to determine the locationfor the installation of the main signals,- calculated block lengths, and- calculations of optimal head ways, that have not been studiedin detail although they deserve special attention due totheir impact.Generally speaking, the signals are installed in compliancewith the local circumstances, i. e. according to the technicaland technological characteristics and conditions determinedby the traffic places of work they protect.The distribution and length of the blocks depend on: therailway line and its exploitation characteristics, structure andtype of trains that run on the railway line, traffic organisationand signalisation system, as well as technical and exploitationcharacte1istics of the traction vehicles and the rolling stock.What has to be considered is that the minimum section lengthcannot be shorter than the length of the braking distance, i. e.the length of the longest train which runs on the respective railwayline.The study of these parameters is supplemented by the calculationof the reduction in throughput capacity depending on thelack of uniformity in the operation of trains, which, in order tomaintain the design quality of the transportation se1vice, and inthe activities of establishing and implementing the business policyshouldn't be left out nor bypassed.

  8. Experimental study on the unstable direct contact condensation regimes

    International Nuclear Information System (INIS)

    Damasio, C.; Del Tin, G.; Fiegna, G.; Malandrone, M.

    1985-01-01

    Vapour-liquid interface fluctuation frequencies have been measured by means of electrical resistive probes. Frequency data from these probes have been compared with measured frequencies from a Kistler piezoelectric pressure transducer in the pool near the steam-water interaction region. An attempt has been made to correlate measured frequencies to the observed condensation regimes. Experimental data concerning ''steam chugging'' and condensation oscillation regimes have been correlated in terms of dimensionless parameters

  9. Theoretical and experimental study of thermoacoustic engines

    Science.gov (United States)

    Raspet, Richard; Bass, Henry E.; Arnott, W. P.

    1992-12-01

    A three year study of thermoacoustic engines operating as prime movers and refrigerators was completed. The major thrust of this effort was the use and theoretical description of ceramic honeycomb structures as the active element in thermoacoustic engines. An air-filled demonstration prime mover was constructed and demonstrated at Acoustical Society of America and IEE meetings. A helium-filled test prime mover was designed and built an is being employed in studies of the threshold of oscillation as a function of temperature difference and pressure. In addition, acoustically based theories of the thermoacoustic engine have been developed and tested for a parallel plate stack at the Naval Postgraduate School and for a honeycomb stack at the University of Mississippi. Most of this work is described in detail in the attached publications. In this report we will give an overview of the research completed to date and its relationship to work performed at the Naval Postgraduate School and to future work at the University of Mississippi.

  10. Field experimentation in isotope-aided studies

    International Nuclear Information System (INIS)

    Zapata, F.

    1990-01-01

    Isotopic-aided studies involve the application of isotopically labelled fertilizer as tracers for the quantitative and precise determination of the fate of specific nutrient elements in the soil/plant system. The planning of isotopic-aided studies requires a different approach from that followed in the design of normal fertilizer trials because of the cost and supply of isotopically labelled materials, the use of highly specialized equipment and the need for skillful trained staff in the use of isotope techniques both in the field/greenhouse and the laboratory. This report is intended to highlight the main points to be considered while applying those techniques in the field or greenhouse. It has been well established that nuclear techniques are a powerful tool in agricultural research. One should take advantage of the use of such techniques if the following criteria are met: The isotope method is the only way to solve a particular question or to obtain a specific piece of information. There are other methods available for such a purpose but the nuclear method provides a direct and quick means to obtain the needed information resulting in higher economic return

  11. Studies of thermal-reactor benchmark-data interpretation: experimental corrections

    International Nuclear Information System (INIS)

    Sher, R.; Fiarman, S.

    1976-10-01

    Experimental values of integral parameters of the lattices studied in this report, i.e., the MIT(D 2 O) and TRX benchmark lattices have been re-examined and revised. The revisions correct several systematic errors that have been previously ignored or considered insignificant. These systematic errors are discussed in detail. The final corrected values are presented

  12. A dense Pd/Ag membrane reactor for methanol steam reforming: Experimental study

    NARCIS (Netherlands)

    Basile, A.; Gallucci, F.; Paturzo, L.

    2005-01-01

    This paper focuses on an experimental study of the methanol steam reforming (MSR) reaction. A dense Pd/Ag membrane reactor (MR) has been used, and its behaviour has been compared to the performance of a traditional reactor (TR) packed with the same catalyst type and amount. The parameters

  13. Experimental Study of Stable Surfaces for Anti-Slug Control in Multi-phase Flow

    DEFF Research Database (Denmark)

    Pedersen, Simon; Løhndorf, Petar Durdevic; Stampe, Kasper

    2016-01-01

    , the slug can be avoided or eliminated by proper facility design or control of operational conditions. Based on a testing facility which can emulate a pipeline-riser or a gas-lifted production well in a scaled-down manner, this paper experimentally studies the correlations of key operational parameters...

  14. Development of multiple performance indices and system parameter study for the design of a MEMS accelerometer

    International Nuclear Information System (INIS)

    Kim, Yong Il; Choi, Chan Kyu; Yoo, Hong Hee

    2012-01-01

    For the design of a MEMS accelerometer, proper performance indices should be defined and employed. Performance indices are obtained using either an experimental method or a numerical method. In the present study, a vibration analysis model of a MEMS accelerometer is introduced to calculate three performance indices: sensitivity, measurable acceleration range, and measurable frequency range. The accuracy of the vibration analysis model is first validated by comparing its modal and transient results with those of a commercial finite element code. Measurable acceleration and frequency ranges versus allowable errors for electrical and mechanical sensitivities are obtained and the effects of system parameter variations on the three performance indices are investigated

  15. On the study of level density parameters for some deformed light nuclei

    International Nuclear Information System (INIS)

    Sonmezoglu, S.

    2005-01-01

    The nuclear level density, which is the number of energy levels/MeV at an excitation energy Ex , is a characteristic property of every nucleus. Total level densities are among the key quantities in statistical calculations in many fields, such as nuclear physics, astrophysics, spallation s neutrons measurements, and studies of intermediate-energy heavy-ion collisions. The nuclear level density is an important physical quantity both from the fundamental point of view as well as in understanding the particle and gamma ray emission in various reactions. In light and heavy deformed nucleus, the gamma-ray energies drop with decreasing spin in a very regular fashion. The nuclear level density parameters have been usually used in investigation of the nuclear level density. This parameter itself changes with excitation energy depending on both shell effect in the single particle model and different excitation modes in the collective models. In this study, the energy level density parameters of some deformed light nucleus (40 C a, 47 T i, 59 N i, 79 S e, 80 B r) are determined by using energy spectrum of the interest nucleus for different band. In calculation of energy-level density parameters dependent upon excitation energy of nuclei studied, a model was considered which relies on the fact that energy levels of deformed light nuclei, just like those of deformed heavy nuclei, are equidistant and which relies on collective motions of their nucleons. The present calculation results have been compared with the corresponding experimental and theoretical results. The obtained results are in good agreement with the experimental results

  16. Experimental techniques for cement hydration studies

    Directory of Open Access Journals (Sweden)

    Andreas Luttge

    2011-10-01

    Full Text Available Cement hydration kinetics is a complex problem of dissolution, nucleation and growth that is still not well understood, particularly in a quantitative way. While cement systems are unique in certain aspects they are also comparable to natural mineral systems. Therefore, geochemistry and particularly the study of mineral dissolution and growth may be able to provide insight and methods that can be utilized in cement hydration research. Here, we review mainly what is not known or what is currently used and applied in a problematic way. Examples are the typical Avrami approach, the application of Transition State Theory (TST to overall reaction kinetics and the problem of reactive surface area. Finally, we suggest an integrated approach that combines vertical scanning interferometry (VSI with other sophisticated analytical techniques such as atomic force microscopy (AFM and theoretical model calculations based on a stochastic treatment.

  17. Experimental study of diffuse auroral precipitations

    International Nuclear Information System (INIS)

    Mouaia, K.

    1983-01-01

    First chapter is devoted to low energy electron precipitation in the evening sector of the auroral magnetosphere, during quiet and disturbed magnetic periods. Four subjects are studied in detail: the latitude distribution of the varied auroral forms and their relations to external magnetosphere; the time coefficients related to precipitations, the form and the dynamic of the diffuse precipitation equatorial frontier; the precipitation effect on the ionosphere concentration. The last part of the chapter shows that the plasma convection in the magnetosphere, associated to wave-particle interactions near the equatorial accounts for the principal characteristics of the evening sector diffuse electronic precipitations. The second chapter deals with subauroral precipitations of low energy ions, after the magnetospheric substorms, in the high latitude regions of the morning sector [fr

  18. Experimental study on the adiabatic shear bands

    International Nuclear Information System (INIS)

    Affouard, J.

    1984-07-01

    Four martensitic steels (Z50CDV5 steel, 28CND8 steel, 35NCDV16 steel and 4340 steel) with different hardness between 190 and 600 Hsub(B) (Brinell hardness), have been studied by means of dynamic compressive tests on split Hopkinson pressure bar. Microscopic observations show that the fracture are associated to the development of adiabatic shear bands (except 4340 steel with 190 Hsub(B) hardness). By means of tests for which the deformation is stopped at predetermined levels, the measurement of shear and hardness inside the band and the matrix indicates the chronology of this phenomenon: first the localization of shear, followed by the formation of adiabatic shear band and ultimatly crack initiation and propagation. These results correlated with few simulations by finite elements have permitted to suggest two mecanisms of deformation leading to the formation of adiabatic shear bands in this specific test [fr

  19. Experimental Study of Liquid Fuel Spray Combustion

    DEFF Research Database (Denmark)

    Westlye, Fredrik Ree

    the specific physical quantities needed in CFD validation of these types of flames. This work is a testament to that fact. The first part of this thesis is an extensive study of optical combustion diagnostics applied to complex transient sprayflames in a high temperature and pressure environment...... by the Danish Council for Strategic Research. Other supporters of the project have been MAN Diesel & Turbo A/S, DTU Mechanical Engineering, DTU Chemical Engineering, Sandia National Laboratories USA, Norwegian University of Science & Technology (NTNU) and University of Nottingham, Malaysia Campus.......The physiochemical properties and electromagnetic interactions in flames, of which various optical combustion diagnostics are based, have been reviewed. Key diagnostics have been presented with practical examples of their application which, together with a comprehensive review of fuel spray flames, form...

  20. Preliminary experimental studies of waste coal gasification

    Energy Technology Data Exchange (ETDEWEB)

    Su, S.; Jin, Y.G.; Yu, X.X.; Worrall, R. [CSIRO, Brisbane, QLD (Australia). Advanced Coal Technology

    2013-07-01

    Coal mining is one of Australia's most important industries. It was estimated that coal washery rejects from black coal mining was approximately 1.82 billion tonnes from 1960 to 2009 in Australia, and is projected to produce another one billion tonnes by 2018 at the current production rate. To ensure sustainability of the Australian coal industry, we have explored a new potential pathway to create value from the coal waste through production of liquid fuels or power generation using produced syngas from waste coal gasification. Consequently, environmental and community impacts of the solid waste could be minimized. However, the development of an effective waste coal gasification process is a key to the new pathway. An Australian mine site with a large reserve of waste coal was selected for the study, where raw waste coal samples including coarse rejects and tailings were collected. After investigating the initial raw waste coal samples, float/sink testing was conducted to achieve a desired ash target for laboratory-scale steam gasification testing and performance evaluation. The preliminary gasification test results show that carbon conversions of waste coal gradually increase as the reaction proceeds, which indicates that waste coal can be gasified by a steam gasification process. However, the carbon conversion rates are relatively low, only reaching to 20-30%. Furthermore, the reactivity of waste coal samples with a variety of ash contents under N{sub 2}/air atmosphere have been studied by a home-made thermogravimetric analysis (TGA) apparatus that can make the sample reach the reaction temperature instantly.

  1. Experimental and clinical studies with intraoperative radiotherapy

    International Nuclear Information System (INIS)

    Sindelar, W.F.; Kinsella, T.; Tepper, J.; Travis, E.L.; Rosenberg, S.A.; Glatstein, E.

    1983-01-01

    Studies of normal tissue tolerance to intraoperative radiotherapy were done upon 65 dogs subjected to laparotomy and 11 million electron volt electron irradiation in doses ranging from zero to 5,000 rads. Results of studies indicated that intact aorta and vena cava tolerate up to 5,000 rads without loss of structural integrity. Ureteral fibrosis and stenosis develop at doses of 3,000 rads or more. Arterial anastomoses heal after doses of 4,500 rads, but fibrosis can lead to occlusion. Intestinal suture lines heal after doses of 4,500 rads. Bile duct fibrosis and stenosis develop at doses of 2,000 rads or more. Biliary-enteric anastomoses fail to heal at any dose level. A clinical trial of intraoperative radiotherapy combined with radical surgery was performed upon 20 patients with advanced malignant tumors which were considered unlikely to be cured by conventional therapies and which included carcinomas of the stomach, carcinomas of the pancreas, carcinomas involving the hilus of the liver, retroperitoneal sarcomas and osteosarcomas of the pelvis. All patients underwent resection of gross tumor, followed by intraoperative irradiation of the tumor bed and regional nodal basins. Some patients received additional postoperative external beam radiotherapy. Treatment mortality for combined operation and radiotherapy occurred in four of 20 patients. Postoperative complications occurred in four of the 16 surviving patients. Local tumor control was achieved in 11 of the 16 surviving patients, with an over-all median follow-up period of 18 months. The clinical trial suggested that intraoperative radiotherapy is a feasible adjunct to resection in locally advanced tumors, that the resulting mortality and morbidity is similar to that expected from operation alone and that local tumor control may be improved

  2. Numerical and experimental study of capillary forces in trapezoid microgrooves

    Science.gov (United States)

    Sheu, Tsung-Sheng; Ding, Pei-Pei; Chen, Ping-Hei

    1999-08-01

    The evaporation of thin liquid films is of significant importance in a wide variety of heat transfer problems. The vaporization process of thin liquid films in a trapezoid microgroove channel was investigated both numerically and experimentally. In order to predict the wetted axial length of capillary flow in a trapezoid microgroove, the nonlinear governing equation was solved numerically and a simplified algebraic equation was also derived. The parameters include the input heat flux, tilt angle of grooved surface, thermophysical properties of working fluid, and geometric parameters of microgrooves. In order to investigate the effect of geometric parameters of microgrooves on the wetted axial length, a series of either trapezoid or triangular microgrooves was machined on the surface of copper test devices for experimental measurements. Measurements were conducted using either methanol or ethanol as working fluid at four different tilt angles of grooved surface and four applied input heat flux values. The wetted axial length was measured using microscopy observation. The predicted results of the algebraic equation are found to be in reasonable agreement with the experimental data, especially for cases of higher tilt angle or higher heat flux. Besides, using microgrooves of triangular shape or using methanol as working fluid can increase the wetted axial length of microgrooves.

  3. Characterization of an erbium doped fiber amplifier starting from its experimental parameters; Caracterizacion de un amplificador de fibra dopada con erbio a partir de sus parametros experimentales

    Energy Technology Data Exchange (ETDEWEB)

    Bello J, M.; Kuzin, E.A.; Ibarra E, B. [Instituto Nacional de Astrofisica, Optica y Electronica (INAOE), Luis Enrique Erro No. 1, TonantzintIa, 72000 Puebla (Mexico); Tellez G, R. [Instituto Mexicano del Petroleo, Eje Central Lazaro Cardenas No 152, Delegacion Gustavo A. Madero, 07730 Mexico D.F. (Mexico)]. e-mail: mabello@inaoep.mx

    2007-07-01

    In this paper we describe a method to characterize the gain of an erbium-doped fiber amplifier (EDFA) through the numerical simulation of the signal beam along the amplifier. The simulation is based on a model constituted by the propagation and rate equations for an erbium-doped fiber. The manipulation of these equations allows us to regroup the parameters present in an EDFA, which we have named the A, B, C, D parameters, and they can be obtained experimentally from an erbium-doped fiber. Experimental results show that the measurement of these parameters allow us to estimate with very good correspondence the amplifier gain. (Author)

  4. Experimental and clinical studies on CT lymphography

    International Nuclear Information System (INIS)

    Hirata, Yuzo; Kono, Michio

    1982-01-01

    Indirect lymphography using computed tomographic apparatus (CT Lymphography) was attempted in 15 dogs with newly devised contrast medium for the opacification of hilar and mediastinal lymphnodes. Clinical application was performed in 2 cases of lung cancer. Newly devised contrast material is an emulsion, which consists of oily contrast medium, non-ionic surfactant and glucose solution. The contrast medium was injected percutaneously into subdiaphragmatic space, or into bronchial walls by bronchofiberscopic technique. CT was able to demonstrate the opacified hilar and mediastinal nodes much more in number than demonstrated in conventional radiograms. It was true in 6 to 11 cases when injected into subdiaphragmatic spaces, and in 2 of 4 cases with an injection into bronchial walls. In clinical studies, CT revealed opacification of mediastinal nodes in one case of lung cancer. Although the procedure is still inferior to the demonstrability of routine indirect lymphography for the evaluation of the fine structure of each node, it showed no remarkable side effects. As the satisfactory method of opacifying hilar and mediastinal nodes has not yet been established, our method is thought to be of value in applying for detection of the metastatic lymphnodes. (author)

  5. Experimental study of acoustic vibration in BWRs

    International Nuclear Information System (INIS)

    Kumagai, Kosuke; Someya, Satoshi; Okamoto, Koji

    2009-01-01

    In recent years, the power uprate of Boiling Water Reactors have been conducted at several existing power plants as a way to improve plant economy. In one of the power uprated plants (117.8% uprates) in the United States, the steam dryer breakages due to fatigue fracture occurred. It is conceivable that the increased steam flow passing through the branches caused a self-induced vibration with the propagation of sound wave into the steam-dome. The resonance among the structure, flow and the pressure fluctuation resulted in the breakages. To understand the basic mechanism of the resonance, previous researches were done by a point measurement of the pressure and by a phase averaged measurement of the flow, while it was difficult to detect the interaction among them by the conventional method. In this study, Dynamic Particle Image Velocimetry (PIV) System was applied to investigate the effect of sound on natural convection and forced convection. Dynamic PIV system is the newest entrant to the field of fluid flow measurement. Its paramount advantage is the instantaneous global evaluation of conditions over plane extended across the whole velocity field. Also, to evaluate the coupling between the acoustic wave and structure (simulated as tuning fork vibrator in this experiment), in the resonance frequency of tuning fork vibrator, fluid behavior and the motion of tuning fork vibrator are measured simultaneously. (author)

  6. Experimental study of canvas characterization for paintings

    Science.gov (United States)

    Cornelis, Bruno; Dooms, Ann; Munteanu, Adrian; Cornelis, Jan; Schelkens, Peter

    2010-02-01

    The work described here fits in the context of a larger project on the objective and relevant characterization of paintings and painting canvas through the analysis of multimodal digital images. We captured, amongst others, X-ray images of different canvas types, characterized by a variety of textures and weave patterns (fine and rougher texture; single thread and multiple threads per weave), including raw canvas as well as canvas processed with different primers. In this paper, we study how to characterize the canvas by extracting global features such as average thread width, average distance between successive threads (i.e. thread density) and the spatial distribution of primers. These features are then used to construct a generic model of the canvas structure. Secondly, we investigate whether we can identify different pieces of canvas coming from the same bolt. This is an important element for dating, authentication and identification of restorations. Both the global characteristics mentioned earlier and some local properties (such as deviations from the average pattern model) are used to compare the "fingerprint" of different pieces of cloth coming from the same or different bolts.

  7. Experimental study of high beta toroidal plasmas

    International Nuclear Information System (INIS)

    Kellman, A.G.

    1983-09-01

    Experiments on the Wisconsin Levitated Toroidal Octupole have produced a wide range of stable high β plasmas with β significantly above single fluid MHD theory predictions. A stable β approx. 8% plasma, twice the fluid limit, is obtained with 5 rho/sub i/ approx. L/sub n/ and tau/sub β/ approx. = 6000 tau/sub Alfven/ = 600 μsec. The enhanced stability is explained with a kinetic treatment that includes the effect of finite ion gyroradius which couples the ballooning mode to an ion drift wave. In a more collisional, large gyroradius (2 rho/sub i/ approx. L/sub n/) regime, a stable β approx. 35% plasma is obtained with a decay time of 1000 Alfven times. Measurement of the equilibrium magnetic field in this regime indicates that the diamagnetic current density is five times smaller than predicted by ideal MHD, probably due to ion gyroviscosity. Particle transport is anomalous and ranges from agreement with the classical diffusion rate at the highest beta, lowest field plasma (B/sub P/ = 200 G), to thirteen times the classical rate in a β=11%, high field plasma (B/sub P/ = 860 G) where the level of enhancement increase with magnetic field. Fluctuations in density, electrostatic potential, and magnetic field have been studied in plasmas with β from 0.1% to 40%

  8. Experimental study of flow through compressor Cascade

    Directory of Open Access Journals (Sweden)

    Satyam Panchal

    2017-09-01

    Full Text Available The objective of this research work is to study the behaviour of flow at the inlet, within the blade passage and at the exit of a compressor cascade. For this purpose, a cascade with six numbers of aerofoil blades was designed and constructed. The cascade was fitted on the cascade test tunnel. Out of six blades two were instrumented for measuring the pressure distribution on the pressure and suction surface. The blades had a parabolic camber line, with a maximum camber position at 40% of the chord from the leading edge of the blade. The profile of the blade was C4, height of the blade was 160 mm, chord length was 80 mm, camber angle was 45° and stagger angle was 30°. Similarly, the length of the cascade was 300 mm, span was 160 mm, pitch was 60 mm, the actual chord of the cascade was 80 mm, the axial chord of the cascade was 70 mm, the stagger angle of the cascade was 30° and the pitch-chord ratio was 0.75. The data was taken and analyzed at −500% of the axial chord before the cascade, −25% of the axial chord before the leading edge, 25%, 50%, 75% and 150% of the axial chord from the leading edge of the blade. The readings were taken from the cascade wall to the mid span position along the pitch wise direction. The angle of incidence was also changed during the experiment and varied from i=−50°, −30°, −10° to 5°.

  9. Markets and Morals: An Experimental Survey Study

    Science.gov (United States)

    Elias, Julio J.; Lacetera, Nicola; Macis, Mario

    2015-01-01

    Most societies prohibit some market transactions based on moral concerns, even when the exchanges would benefit the parties involved and would not create negative externalities. A prominent example is given by payments for human organs for transplantation, banned virtually everywhere despite long waiting lists and many deaths of patients who cannot find a donor. Recent research, however, has shown that individuals significantly increase their stated support for a regulated market for human organs when provided with information about the organ shortage and the potential beneficial effects a price mechanism. In this study we focused on payments for human organs and on another “repugnant” transaction, indoor prostitution, to address two questions: (A) Does providing general information on the welfare properties of prices and markets modify attitudes toward repugnant trades? (B) Does additional knowledge on the benefits of a price mechanism in a specific context affect attitudes toward price-based transactions in another context? By answering these questions, we can assess whether eliciting a market-oriented approach may lead to a relaxation of moral opposition to markets, and whether there is a cross-effect of information, in particular for morally controversial activities that, although different, share a reference to the “commercialization” of the human body. Relying on an online survey experiment with 5,324 U.S. residents, we found no effect of general information about market efficiency, consistent with morally controversial markets being accepted only when they are seen as a solution to a specific problem. We also found some cross-effects of information about a transaction on the acceptance of the other; however, the responses were mediated by the gender and (to a lesser extent) religiosity of the respondent—in particular, women exposed to information about legalizing prostitution reduced their stated support for regulated organ payments. We relate

  10. Markets and morals: an experimental survey study.

    Directory of Open Access Journals (Sweden)

    Julio J Elias

    Full Text Available Most societies prohibit some market transactions based on moral concerns, even when the exchanges would benefit the parties involved and would not create negative externalities. A prominent example is given by payments for human organs for transplantation, banned virtually everywhere despite long waiting lists and many deaths of patients who cannot find a donor. Recent research, however, has shown that individuals significantly increase their stated support for a regulated market for human organs when provided with information about the organ shortage and the potential beneficial effects a price mechanism. In this study we focused on payments for human organs and on another "repugnant" transaction, indoor prostitution, to address two questions: (A Does providing general information on the welfare properties of prices and markets modify attitudes toward repugnant trades? (B Does additional knowledge on the benefits of a price mechanism in a specific context affect attitudes toward price-based transactions in another context? By answering these questions, we can assess whether eliciting a market-oriented approach may lead to a relaxation of moral opposition to markets, and whether there is a cross-effect of information, in particular for morally controversial activities that, although different, share a reference to the "commercialization" of the human body. Relying on an online survey experiment with 5,324 U.S. residents, we found no effect of general information about market efficiency, consistent with morally controversial markets being accepted only when they are seen as a solution to a specific problem. We also found some cross-effects of information about a transaction on the acceptance of the other; however, the responses were mediated by the gender and (to a lesser extent religiosity of the respondent--in particular, women exposed to information about legalizing prostitution reduced their stated support for regulated organ payments. We

  11. Markets and morals: an experimental survey study.

    Science.gov (United States)

    Elias, Julio J; Lacetera, Nicola; Macis, Mario

    2015-01-01

    Most societies prohibit some market transactions based on moral concerns, even when the exchanges would benefit the parties involved and would not create negative externalities. A prominent example is given by payments for human organs for transplantation, banned virtually everywhere despite long waiting lists and many deaths of patients who cannot find a donor. Recent research, however, has shown that individuals significantly increase their stated support for a regulated market for human organs when provided with information about the organ shortage and the potential beneficial effects a price mechanism. In this study we focused on payments for human organs and on another "repugnant" transaction, indoor prostitution, to address two questions: (A) Does providing general information on the welfare properties of prices and markets modify attitudes toward repugnant trades? (B) Does additional knowledge on the benefits of a price mechanism in a specific context affect attitudes toward price-based transactions in another context? By answering these questions, we can assess whether eliciting a market-oriented approach may lead to a relaxation of moral opposition to markets, and whether there is a cross-effect of information, in particular for morally controversial activities that, although different, share a reference to the "commercialization" of the human body. Relying on an online survey experiment with 5,324 U.S. residents, we found no effect of general information about market efficiency, consistent with morally controversial markets being accepted only when they are seen as a solution to a specific problem. We also found some cross-effects of information about a transaction on the acceptance of the other; however, the responses were mediated by the gender and (to a lesser extent) religiosity of the respondent--in particular, women exposed to information about legalizing prostitution reduced their stated support for regulated organ payments. We relate these

  12. Study of operational parameters on the performance of micro PEMFCs with different flow fields

    International Nuclear Information System (INIS)

    Hsieh, S.-S.; Yang, S.-H.; Kuo, J.-K.; Huang, C.-F.; Tsai, H.-H.

    2006-01-01

    The effects of different operating parameters on micro PEMFC performances were experimentally studied for three different flow field configurations (interdigitated, mesh, and serpentine). Experiments with different cell operating temperatures and different backpressures on the H 2 flow channels, as well as various combinations of these parameters, have been conducted for three different flow geometries. The micro PEMFCs were designed and fabricated inhouse through a deep UV lithography technique and the SU-8 photoresist was used as microstructure material for the fuel cell flow field plates. Results are presented in the form of polarization VI curves and PI curves under different operating conditions. The possible transport mechanisms associated with the parametric effects were discussed. In addition, it was found that among the three flow patterns considered, significant improvements can be reached with a specified flow geometry

  13. Dielectric and electro-optical parameters of two ferroelectric liquid crystals: a comparative study

    International Nuclear Information System (INIS)

    Kumar Misra, Abhishek; Kumar Srivastava, Abhishek; Shukla, J P; Manohar, Rajiv

    2008-01-01

    Dielectric relaxation and an electro-optical study of two ferroelectric liquid crystals having different spontaneous polarizations (Felix 16/100 and Felix 17/000) showing SmC* and SmA phases have been performed in the temperature range 30-80 compfn C. The experimental data have been used to determine different relaxation parameters, viz. distribution parameter, relaxation frequency, dielectric strength and rotational viscosity. The Goldstone mode of dielectric permittivity has been well observed for both the samples under investigation. The activation energy of both the samples has also been determined by the best theoretical fitting of the Arrhenius plot. We have also evaluated the optical response time and anchoring energy coefficients from electro-optical measurement techniques for these samples.

  14. An experimental study on pump clogging

    International Nuclear Information System (INIS)

    Isono, M; Nohmi, M; Uchida, H; Kawai, M; Kudo, H; Kawahara, T; Miyagawa, K; Saito, S

    2014-01-01

    For sewage pump that various foreign substance is flowed into, anti-clogging performance is a factor as important as pump efficiency in order to avoid clogging trouble by foreign substance. Many investigations about pump inner flow and pump efficiency estimation have been carried out conventionally in order to realize coexistence with anti-clogging performance and pump performance. And these results have been reflected in construction of the running water section design method. As a index of anti-clogging performance, ''impeller passage diameter'' which is diameter of spherical solid that can pass through the pump is used widely. And there are various type of the sewage pump which have large impeller passage diameter. However real cause of clog is not a solid, and it is fibrous material such as towel and clothes, vinyl and paper diaper. In most case these material accumulate in the pump, so that clog is occurred. In this study, for the purpose of quantification of anti-clogging performance against fibrous materials, the factor that affect to clogging of pump was investigated by pump model test using a string. The test is done based on Taguchi method. In this test, type of the pump model, diameter of the string, material of the string, length of the string and flow rate are selected for the factor, and the effect that they have on the clogging of the pump was investigated. As a result of this test, it was made clear that length of the string has a strong influence on the clogging of the pump. And from the result of this test, evaluation method of anti-clogging performance of the pump against fibrous material by using string was considered. According to the result of above test based on Taguchi method, it was assumed that quantification of anti-clogging performance against fibrous materials is possible by flowing plural strings into the pump and calculating the probability of passing. Plurality sewage pumps of different types were evaluated based

  15. Theory and experimental verifications of the resonator Q and equivalent electrical parameters due to viscoelastic and mounting supports losses.

    Science.gov (United States)

    Yong, Yook-Kong; Patel, Mihir S; Tanaka, Masako

    2010-08-01

    A novel analytical/numerical method for calculating the resonator Q and its equivalent electrical parameters due to viscoelastic, conductivity, and mounting supports losses is presented. The method presented will be quite useful for designing new resonators and reducing the time and costs of prototyping. There was also a necessity for better and more realistic modeling of the resonators because of miniaturization and the rapid advances in the frequency ranges of telecommunication. We present new 3-D finite elements models of quartz resonators with viscoelasticity, conductivity, and mounting support losses. The losses at the mounting supports were modeled by perfectly matched layers (PMLs). A previously published theory for dissipative anisotropic piezoelectric solids was formulated in a weak form for finite element (FE) applications. PMLs were placed at the base of the mounting supports to simulate the energy losses to a semi-infinite base substrate. FE simulations were carried out for free vibrations and forced vibrations of quartz tuning fork and AT-cut resonators. Results for quartz tuning fork and thickness shear AT-cut resonators were presented and compared with experimental data. Results for the resonator Q and the equivalent electrical parameters were compared with their measured values. Good equivalences were found. Results for both low- and high-Q AT-cut quartz resonators compared well with their experimental values. A method for estimating the Q directly from the frequency spectrum obtained for free vibrations was also presented. An important determinant of the quality factor Q of a quartz resonator is the loss of energy from the electrode area to the base via the mountings. The acoustical characteristics of the plate resonator are changed when the plate is mounted onto a base substrate. The base affects the frequency spectra of the plate resonator. A resonator with a high Q may not have a similarly high Q when mounted on a base. Hence, the base is an

  16. Experimental and Numerical Study of Twin Underexpanded Impinging Jets

    Institute of Scientific and Technical Information of China (English)

    Minoru Yaga; Minoru Okano; Masumi Tamashiro; Kenyu Oyakawa

    2003-01-01

    In this paper, the dual underexpanded impinging jets are experimentally and numerically studied. The experiments were performed by measuring the unsteady and averaged wall static pressures and by visualizing density fields using schlieren method. Numerical calculations were also conducted by solving unsteady three dimensional compressible Navier-Stokes equations with Baldwin-Lomax turbulence model. The main parameters for the dual jets are the non-dimensional distance between the two nozzle centers H/D covering 1.5, 2.0, the nozzle to plate separation L/D 2.0, 3.0,4.0 and 5.0 and the pressure ratio defined by Po/Pb 1.0~6.0, where D is the diameter of each nozzle exit, Po the stagnation pressure and Pb the back pressure. It is found that the agreement between the experiments and the calculations is good. The fountain flow at the middle of the two jets is observed both in the experiments and the calculation. According to FFT analysis of the experiments for the twin jets,relatively low frequency (up to 5 kHz) is dominant for H/D =1.5, L/D =2.0 and pressure ratio Po/Pb =3.0 and 5.0,which is confirmed by the experiments.

  17. Experimental study of liquid drop impact onto a powder surface

    KAUST Repository

    Marston, Jeremy; Thoroddsen, Sigurdur T; Ng, Waikiong; Tan, Reginald

    2010-01-01

    The initial dynamics of liquid drop impact onto powder surfaces is studied experimentally using high-speed photography. For a range of bed packing fractions, φ, liquid physical properties and impact velocities, ui, we observe a variety of phenomena that can be representative of a hydrophobic surface, a rough surface or a porous medium. The solids packing fraction in the bed, 0.38≤φ≤0.65, and the impact Weber number, 3.5≤We=ρDui 2/φ≤750, (where ρ, D and φ are the drop density, diameter and surface tension respectively) are shown to be the critical parameters governing the outcome of an impact. For high packing fractions, φ≳0.5, we show that the observed spreading, rebound and splashing can be broadly characterised in terms of the Weber number while for looser packing fractions, φ≲0.5, we observe powder ejectas and provide a qualitative description of the granule nucleation at the centre of the impact sites. © 2010 Elsevier B.V.

  18. Thermochemical study of cyanopyrazines: Experimental and theoretical approaches

    International Nuclear Information System (INIS)

    Miranda, Margarida S.; Morais, Victor M.F.; Matos, M. Agostinha R.

    2006-01-01

    The standard (p - bar =0.1MPa) molar energy of combustion, at T=298.15K, of crystalline 2,3-dicyanopyrazine was measured by static bomb calorimetry, in oxygen atmosphere. The standard molar enthalpy of sublimation, at T=298.15K, was obtained by Calvet Microcalorimetry, allowing the calculation of the standard molar enthalpy of formation of the compound, in the gas phase, at T=298.15K: Δ f H m - bar (g)=(518.7+/-3.4)kJ.mol -1 . In addition, the geometries of all cyanopyrazines were obtained using density functional theory with the B3LYP functional and two basis sets: 6-31G* and 6-311G**. These calculations were then used for a better understanding of the relation between structure and energetics of the cyanopyrazine systems. These calculations also reproduce measured standard molar enthalpies of formation with some accuracy and do provide estimates of this thermochemical parameter for those compounds that could not be studied experimentally, namely the tri- and tetracyanopyrazines: the strong electron withdrawing cyano group on the pyrazine ring makes cyanopyrazines highly destabilized compounds

  19. Experimental study and modelling of iron ore reduction by hydrogen

    International Nuclear Information System (INIS)

    Wagner, D.

    2008-01-01

    In an effort to find new ways to drastically reduce the CO 2 emissions from the steel industry (ULCOS project), the reduction of iron ore by pure hydrogen in a shaft furnace was investigated. The work consisted of literature, experimental, and modelling studies. The chemical reaction and its kinetics were analysed on the basis of thermogravimetric experiments and physicochemical characterizations of partially reduced samples. A specific kinetic model was designed, which simulates the successive reactions, the different steps of mass transport, and possible iron sintering, at the particle scale. Finally, a 2-dimensional numerical model of a shaft furnace was developed. It depicts the variation of the solid and gas temperatures and compositions throughout the reactor. One original feature of the model is using the law of additive characteristic times for calculating the reaction rates. This allowed us to handle both the particle and the reactor scale, while keeping reasonable calculation time. From the simulation results, the influence of the process parameters was assessed. Optimal operating conditions were concluded, which reveal the efficiency of the hydrogen process. (author)

  20. Experimental study on behavior of steel channel strengthened with CFRP

    Directory of Open Access Journals (Sweden)

    Tang Hongyuan

    2017-11-01

    Full Text Available This paper describes the behaviour of axially loaded long and eccentrically loaded short thin-walled steel channels, strengthened with transversely bonded carbon fibre reinforced polymer (CFRP sheets. Seven long members, each 1400 mm long, and seven short members, each 750mmlong, were tested. The main parameters were the number of CFRP plies (one or two and the clear spacing between the CFRP strips (50, 100 or 150 mm. The effect of CFRP sheet layer and clear spacing was studied. All the ultimate load capacity of the reinforced members was improved in different extent. A maximum strength gain of 9.13% was achieved for long members with two CFRP layers and 50 mm spacing of CFRP strips. The experimental results show that the global buckling happens to all the long specimens. For short members, the maximum strength gain of 12.1% was achieved with two CFRP layers and 50 mm spacing of CFRP strips. With the exception of the most heavily reinforced (2 plies at 50 and 100 mm, local buckling was observed prior to global buckling for short members, which was completely opposite of the control specimens. Meanwhile, when the clear spacing of CFRP strips is greater than theweb height of steel channel, the transversely bonded CFRP does not have a significant improvement in buckling load capacity of the short- and long-channel components. While the clear spacing is less than the web height, the more number of CFRP layer, the more enhancement of buckling load capacity.

  1. Numerical and experimental study of bistable plates for morphing structures

    Science.gov (United States)

    Nicassio, F.; Scarselli, G.; Avanzini, G.; Del Core, G.

    2017-04-01

    This study is concerned with the activation energy threshold of bistable composite plates in order to tailor a bistable system for specific aeronautical applications. The aim is to explore potential configurations of the bistable plates and their dynamic behavior for designing novel morphing structure suitable for aerodynamic surfaces and, as a possible further application, for power harvesters. Bistable laminates have two stable mechanical shapes that can withstand aerodynamic loads without additional constraint forces or locking mechanisms. This kind of structures, when properly loaded, snap-through from one stable configuration to another, causing large strains that can also be used for power harvesting scopes. The transition between the stable states of the composite laminate can be triggered, in principle, simply by aerodynamic loads (pilot, disturbance or passive inputs) without the need of servo-activated control systems. Both numerical simulations based on Finite Element models and experimental testing based on different activating forcing spectra are used to validate this concept. The results show that dynamic activation of bistable plates depend on different parameters that need to be carefully managed for their use as aircraft passive wing flaps.

  2. Experimental study of liquid drop impact onto a powder surface

    KAUST Repository

    Marston, Jeremy

    2010-11-01

    The initial dynamics of liquid drop impact onto powder surfaces is studied experimentally using high-speed photography. For a range of bed packing fractions, φ, liquid physical properties and impact velocities, ui, we observe a variety of phenomena that can be representative of a hydrophobic surface, a rough surface or a porous medium. The solids packing fraction in the bed, 0.38≤φ≤0.65, and the impact Weber number, 3.5≤We=ρDui 2/φ≤750, (where ρ, D and φ are the drop density, diameter and surface tension respectively) are shown to be the critical parameters governing the outcome of an impact. For high packing fractions, φ≳0.5, we show that the observed spreading, rebound and splashing can be broadly characterised in terms of the Weber number while for looser packing fractions, φ≲0.5, we observe powder ejectas and provide a qualitative description of the granule nucleation at the centre of the impact sites. © 2010 Elsevier B.V.

  3. Experimental and theoretical studies of metal vapor atoms

    International Nuclear Information System (INIS)

    Whitfield, S.B.; Wehlitz, Ralf; Martins, Michael

    2004-01-01

    Employing electron spectrometry in conjunction with tuneable synchrotron radiation, we will present a detailed examination of the photoionization dynamics of selected metal vapor atoms. In particular, this paper will focus on the relative partial cross sections of the atomic Li K-shell main and satellite (ionization with excitation) photoelectron lines in the region of the strong 1snln'l' autoionizing transitions, the atomic Sc 3d, 4s main and satellite photoelectron lines in the region of the 3p→3d giant resonance, and also the atomic Fe 3d, 4s main and satellite photoelectron lines in the same resonance region. Our experimental data for Sc and Fe will be compared to our state-of-the-art calculations based on the superposition of configuration method developed by Cowan (The Theory of Atomic Structure and Spectra. University of California Berkeley Press, Berkeley and Los Angeles, 1981). Our partial cross section measurements for Li and Sc will be complemented with measurements of the angular distribution parameter, β. In addition, our Li data will also be compared with recent R-matrix calculations (Phys. Rev. 57 (1998) 1045). In the case of Fe, we will also address the term dependent behavior of the partial cross sections on resonance. These results will highlight what can be achieved with today's technology and point the way towards future endeavors in the study of the photoionization dynamics of open-shell metal vapor atoms

  4. An experimental study on drying kinetics of some herbal leaves

    International Nuclear Information System (INIS)

    Kaya, Ahmet; Aydin, Orhan

    2009-01-01

    In this study, thin-layer drying characteristics of some herbal leaves, mainly nettle and mint leaves, are investigated experimentally in a convective drier. Effects of the drying air parameters including temperature, velocity and relative humidity on the total drying time are determined. Initially, sorption isotherms of the dried leaves are determined for different temperatures and equilibrium relative humidity (e.r.h.). Experiments are conducted for air temperatures at 35, 45 and 55 deg. C, velocities at 0.2, 0.4 and 0.6 m/s and, relative humidity values at 40%, 55% and 70%. In the ranges that covered, the values of the moisture diffusivity D eff are obtained between 1.744 x 10 -9 and 4.992 x 10 -9 m 2 /s for nettle leaves and 1.975 x 10 -9 and 6.172 x 10 -9 m 2 /s for mint leaves from the Fick's diffusion model. Using D eff , the value of E a is determined assuming the Arrhenius-type temperature relationship, which varies from 79.873 to 109.003 kJ/mol for nettle leaves and 66.873 to 71.987 kJ/mol for mint leaves

  5. An experimental study on drying kinetics of some herbal leaves

    Energy Technology Data Exchange (ETDEWEB)

    Kaya, Ahmet; Aydin, Orhan [Karadeniz Technical University, Department of Mechanical Engineering, 61080 Trabzon (Turkey)

    2009-01-15

    In this study, thin-layer drying characteristics of some herbal leaves, mainly nettle and mint leaves, are investigated experimentally in a convective drier. Effects of the drying air parameters including temperature, velocity and relative humidity on the total drying time are determined. Initially, sorption isotherms of the dried leaves are determined for different temperatures and equilibrium relative humidity (e.r.h.). Experiments are conducted for air temperatures at 35, 45 and 55 C, velocities at 0.2, 0.4 and 0.6 m/s and, relative humidity values at 40%, 55% and 70%. In the ranges that covered, the values of the moisture diffusivity D{sub eff} are obtained between 1.744 x 10{sup -9} and 4.992 x 10{sup -9} m{sup 2}/s for nettle leaves and 1.975 x 10{sup -9} and 6.172 x 10{sup -9} m{sup 2}/s for mint leaves from the Fick's diffusion model. Using D{sub eff}, the value of E{sub a} is determined assuming the Arrhenius-type temperature relationship, which varies from 79.873 to 109.003 kJ/mol for nettle leaves and 66.873 to 71.987 kJ/mol for mint leaves. (author)

  6. Experimental Investigation of Process Parameters in Drilling LM25 Composites Coated with Multi Wall Carbon Nano Tubes Using Sonication Process

    Directory of Open Access Journals (Sweden)

    Sangeetha M.

    2017-09-01

    Full Text Available Aluminium based metal matrix composites are widely used in automobile components such as cardan shaft of Chevrolet corvette, disc brake and engine push rod. In this experiment a Hybrid Metal Matrix Composites (HMMC are fabricated and drilled. Drilling is the process of making slots in disc brake and thread in the engine parts. The surface quality of the drilled specimen depends on the speed, feed, drill type and the thrust force. Thrust force plays the major role in drilling the specimen. In this experiment HMMCs are fabricated using two processes-called, sonication and casting. Sonication is the process of coating the carbon nanotubes over the silicon carbide particles (SiCp. Semisolid stir casting is used to reinforce the coated SiCp in the LM 25 alloy. A drilling process is performed on HMMC to analyse the extent to which the input parameters influence the thrust force and Ovality. The tools used for drilling are solid carbide tools of three different diameters. Taguchi’s experimental design is adopted for the drilling operation. A mathematical model is used to determine the influence of input parameters on the outputs thrust force and ovality. This paper proves the combination of N3, f1 and d1 of the carbide tool results in the lowest value of thrust force and ovality while drilling HMMCs. In this work the HMMC is prepared by coating the abrasive nature, silicon carbide particle and there is a good interfacial bonding between the reinforced particle and matrix and the drilling process becomes smoother. The new being of this article is the treated ceramics, SiCp with carbon nanotubes. This HMMC shows the improved mechanical properties compared to other metal matrix composites surveyed in the literatures.

  7. Experimental investigation of urea injection parameters influence on NOx emissions from blended biodiesel-fueled diesel engines.

    Science.gov (United States)

    Mehregan, Mina; Moghiman, Mohammad

    2018-02-01

    The present work submits an investigation about the effect of urea injection parameters on NO x emissions from a four-stroke four-cylinder diesel engine fueled with B20 blended biodiesel. An L 9 (3 4 ) Taguchi orthogonal array was used to design the test plan. The results reveal that increasing urea concentration leads to lower NO x emissions. Urea flow rate increment has the same influence on NO x emission. The same result is obtained by an increase in spray angle. Also, according to the analysis of variance (ANOVA), urea concentration and then urea flow rate are the most effective design parameters on NO x emissions, while spray angle and mixing length have less influence on this pollutant emission. Finally, since the result of confirmation test is in good agreement with the predicted value based on the Taguchi technique, the predictive capability of this method in the present study could be deduced.

  8. Theoretical and Experimental Studies in Accelerator Physics

    Energy Technology Data Exchange (ETDEWEB)

    Rosenzweig, James [Univ. of California, Los Angeles, CA (United States). Dept. of Physics and Astronomy

    2017-03-08

    . We note also that PBPL graduates remain as close elaborators for the program after leaving UCLA. The UCLA PBPL program is a foremost developer of on-campus facilities, such as the Neptune and Pegasus Laboratories, providing a uniquely strong environment for student-based research. In addition, the PBPL is a strong user of off-campus national lab facilities, such as SLAC FACET and NLCTA, and the BNL ATF. UCLA has also vigorously participated in the development of these facilities. The dual emphases on off- and on-campus opportunities permit the PBPL to address in an agile way a wide selection of cutting-edge research topics. The topics embraced by this proposal illustrate this program aspect well. These include: GV/m dielectric wakefield acceleration/coherent Cerenkov radiation experiments at FACET (E-201) and the ATF; synergistic laser-excited dielectric accelerator and light source development; plasma wakefield (PWFA) experiments on “Trojan horse” ionization injection (FACET E-210), quasi-nonlinear PWFA at BNL and the production at Neptune high transformer ratio plasma wakes; the inauguration of a new type of RF photoinjector termed “hybrid” at UCLA, and application to PWFA; space-charge dominated beam and cathode/near cathode physics; the study of advanced IFEL systems, for very high energy gain and utilization of novel OAM modes; the physcis of inverse Compton scattering (ICS), with applications to e+ production and γγ colliders; electron diffraction; and advanced beam diagnostics using coherent imaging techniques. These subjects are addressed under the leadership of PBPL director Prof. James Rosenzweig in Task A, and Prof. Pietro Musumeci in Task J, which was initiated following his OHEP Outstanding Junior Investigator award.

  9. Simulation Study on the Controllable Dielectrophoresis Parameters of Graphene

    Science.gov (United States)

    Ji, Jian-Long; Liu, Ya-Li; Ge, Yang; Xie, Sheng-Dong; Zhang, Xi; Sang, Sheng-Bo; Jian, Ao-Qun; Duan, Qian-Qian; Zhang, Qiang; Zhang, Wen-Dong

    2017-03-01

    The method of using dielectrophoresis (DEP) to assemble graphene between micro-electrodes has been proven to be simple and efficient. We present an optimization method for the kinetic formula of graphene DEP, and discuss the simulation of the graphene assembly process based on the finite element method. The simulated results illustrate that the accelerated motion of graphene is in agreement with the distribution of the electric field squared gradient. We also conduct research on the controllable parameters of the DEP assembly such as the alternating current (AC) frequency, the shape of micro-electrodes, and the ratio of the gap between electrodes to the characteristic/geometric length of graphene (λ). The simulations based on the Clausius-Mossotti factor reveal that both graphene velocity and direction are influenced by the AC frequency. When graphene is close to the electrodes, the shape of micro-electrodes will exert great influence on the velocity of graphene. Also, λ has a great influence on the velocity of graphene. Generally, the velocity of graphene would be greater when λ is in the range of 0.4-0.6. The study is of a theoretical guiding significance in improving the precision and efficiency of the graphene DEP assembly. Supported by the Basic Research Project of Shanxi Province under Grant No 2015021092, the National Natural Science Foundation of China under Grant Nos 61471255, 61474079, 61501316, 51505324 and 51622507, and the National High-Technology Research and Development Program of China under Grant No 2015AA042601.

  10. Future Circular Collider Study FCC-he Baseline Parameters

    CERN Document Server

    Bruning, Oliver; Klein, Max; Pellegrini, Dario; Schulte, Daniel; Zimmermann, Frank

    2017-01-01

    Initial considerations are presented on the FCC-he, the electron-hadron collider con guration within the Future Circular Collider study. This note considers arguments for the choice of the electron beam energy based on physics, ep scattering kinematics and cost. The default con guration for the electron accelerator, as for the LHeC, is chosen to be a multi-turn energy recovery linac external to the proton beam tunnel. The main accelerator parameters of the FCC-he are discussed, assuming the concurrent operation of ep with the 100TeV cms energy pp collider. These are compared with the LHeC design concept, for increased performance as for a Higgs facility using the HL-LHC, and also the high energy HE-LHC ep collider configuration. Initial estimates are also provided for the luminosity performance of electron-ion colliders for the 60 GeV electron ERL when combined with the LHC, the HE-LHC and the FCC ion beams.

  11. Injury Based on Its Study in Experimental Models

    Directory of Open Access Journals (Sweden)

    M. Mendes-Braz

    2012-01-01

    Full Text Available The present review focuses on the numerous experimental models used to study the complexity of hepatic ischemia/reperfusion (I/R injury. Although experimental models of hepatic I/R injury represent a compromise between the clinical reality and experimental simplification, the clinical transfer of experimental results is problematic because of anatomical and physiological differences and the inevitable simplification of experimental work. In this review, the strengths and limitations of the various models of hepatic I/R are discussed. Several strategies to protect the liver from I/R injury have been developed in animal models and, some of these, might find their way into clinical practice. We also attempt to highlight the fact that the mechanisms responsible for hepatic I/R injury depend on the experimental model used, and therefore the therapeutic strategies also differ according to the model used. Thus, the choice of model must therefore be adapted to the clinical question being answered.

  12. Parameter studies of sediments in the Storegga Slide region

    Science.gov (United States)

    Yang, S. L.; Kvalstad, T.; Solheim, A.; Forsberg, C. F.

    2006-09-01

    Based on classification tests, oedometer tests, fall-cone tests and triaxial tests, physical and mechanical properties of sediments in the Storegga Slide region were analysed to assess parameter interrelationships. The data show good relationships between a number of physical and mechanical parameters. Goodness of fit between compression index and various physical parameters can be improved by multiple regression analysis. The interclay void ratio and liquidity index correlate well with the undrained shear strength of clay. Sediments with higher water content, liquid limit, activity, interclay void ratio, plasticity index and liquidity index showed higher compression index and/or lower undrained shear strength. Some relationships between parameters were tested by using data from two other sites south of the Storegga Slide. A better understanding of properties of sediments in regions such as that of the Storegga Slide can be obtained through this approach.

  13. Experimental studies on an indigenous coconut shell based ...

    Indian Academy of Sciences (India)

    Experimental studies are carried out to characterize an indigenous, coconut shell based, activated carbon suitable for storage of natural gas. Properties such as BET surface area, micropore volume, average pore diameter and pore size distribution are obtained by using suitable instruments and techniques. An experimental ...

  14. Experimental studies on caisson-type porous seawalls

    Science.gov (United States)

    Zhu, Shutang; Chwang, A. T.

    2002-08-01

    This paper presents experimental studies on the reflection characteristics of caisson-type porous seawalls under designed wave conditions. The results of physical model experiments are plotted and discussed. Comparisons between experimental results and analytical predictions are also made and the agreement is found to be very good.

  15. The experimental study of seed dispersal by fish (ichthyochory)

    NARCIS (Netherlands)

    Pollux, B.J.A.

    2011-01-01

    1.The last few years have seen an increased interest in the experimental study of seed dispersal by fish (ichthyochory). This paper reviews such experiments, aiming to determine what functional aspects of ichthyochory have been investigated, what experimental designs have been used and what the

  16. Theoretical and experimental research on the influence of multiple piezoelectric effects on physical parameters of piezoelectric actuator

    Directory of Open Access Journals (Sweden)

    Liping Shi

    2015-04-01

    Full Text Available Compared with the traditional actuator of machinery and electricity, the piezoelectric actuator has the advantages of a compact structure, small volume, no mechanical friction, athermancy and no electromagnetic interference. Therefore, it has high application value in the fields of MEMS, bioengineering, medical science and so on. This article draws conclusions from the influence of multiple piezoelectric effects on the physical parameters (dielectric coefficient, equivalent capacity, energy conversion and piezoelectric coefficient of piezoelectric actuators. These data from theoretical and experimental research show the following: (1 The rate between the dielectric coefficient of piezoelectric in mechanical freedom and clamping is obtained from the secondary direct piezoelectric effect, which enhances the dielectric property, increases the dielectric coefficient and decreases the coefficient of dielectric isolation; (2 Under external field, E n ( ex = E 1 , exterior stress T = 0, that is to say, under the boundary condition of mechanical freedom, piezoelectric can store electric energy and elasticity, which obtains power density, elastic density and an electromechanical coupling factor; (3 According to the piezoelectric strain S i ( 1 , piezoelectric displacement D m ( 2 and piezoelectric strain S i ( 3 of multiple piezoelectric effects, when the dielectric coefficient of the first converse piezoelectric effect ε33 is 1326 and the dielectric coefficient of the secondary direct piezoelectric effect increases to 3336, the dielectric coefficient of the ceramic chip increases. When the piezoelectric coefficient of the first converse piezoelectric effect d33 is 595 and the piezoelectric coefficient of the secondary direct piezoelectric effect decreases to 240, the piezoelectric coefficient of the ceramic chip will decrease. It is of major significance both in the applications and in basic theory to research the influence of multiple piezoelectric

  17. Experimental study of a high intensity radio-frequency cooler

    Directory of Open Access Journals (Sweden)

    Ramzi Boussaid

    2015-07-01

    Full Text Available Within the framework of the DESIR/SPIRAL-2 project, a radio-frequency quadrupole cooler named SHIRaC has been studied. SHIRaC is a key device of SPIRAL-2, designed to enhance the beam quality required by DESIR. The preliminary study and development of this device has been carried out at Laboratoire de Physique Corpusculaire de CAEN (LPC Caen, France. The goal of this paper is to present the experimental studies conducted on a SHIRaC prototype. The main peculiarity of this cooler is its efficient handling and cooling of ion beams with currents going up as high as 1  μA which has never before been achieved in any of the previous coolers. Much effort has been made lately into these studies for development of appropriate optics, vacuum and rf systems which allow cooling of beams of large emittance (∼80π  mm mrad and high current. The dependencies of SHIRaC’s transmission and the cooled beam parameters in terms of geometrical transverse emittance and the longitudinal energy spread have also been discussed. Investigation of beam purity at optimum cooling condition has also been done. Results from the experiments indicate that an emittance reduction of less than 2.5π  mm mrad and a longitudinal energy spread reduction of less than 4 eV are obtained with more than 70% of ion transmission. The emittance is at expected values whereas the energy spread is not.

  18. Effects of mini trampoline exercise on male gymnasts' physiological parameters: a pilot study.

    Science.gov (United States)

    Karakollukçu, M; Aslan, C S; Paoli, A; Bianco, A; Sahin, F N

    2015-01-01

    There are limited studies that indicate the effects of trampoline exercise on strength and other physiological parameters. This study aims to determine whether twelve weeks of trampoline exercise would have any effects on the physical and physiological parameters of male gymnasts. A number of 20 intercollegiate competitive male gymnasts (as experimental group) and 20 non-athlete male (as control group) participated voluntarily. Their anthropometric characteristics and the anaerobic power were measured and their back strength, vertical jump, standing long jump and 20 meter sprint performances were measured. As a result; whereas 12 weeks of trampoline exercise improved standing long jump (before 242.35±3.40 cm; after 251.70±2.95 cm) and also vertical jump, 20 meter sprint speed and anaerobic power of subjects. We did not observe significant changes on back strength performances (before 148.32±5.73 kg; after 148.10±5.71). The trampoline exercise protocol improved significantly speed, jump and anaerobic performances of the experimental group, while did not induced any changes on back strength performances. More studies are necessary to confirm the interesting results coming from this pilot intervention.

  19. Influence of the operational parameters on bioelectricity generation in continuous microbial fuel cell, experimental and computational fluid dynamics modelling

    Science.gov (United States)

    Sobieszuk, Paweł; Zamojska-Jaroszewicz, Anna; Makowski, Łukasz

    2017-12-01

    The influence of the organic loading rate (also known as active anodic chamber volume) on bioelectricity generation in a continuous, two-chamber microbial fuel cell for the treatment of synthetic wastewater, with glucose as the only carbon source, was examined. Ten sets of experiments with different combinations of hydraulic retention times (0.24-1.14 d) and influent chemical oxygen demand concentrations were performed to verify the impact of organic loading rate on the voltage generation capacity of a simple dual-chamber microbial fuel cell working in continuous mode. We found that there is an optimal hydraulic retention time value at which the maximum voltage is generated: 0.41 d. However, there were no similar effects, in terms of voltage generation, when a constant hydraulic retention time with different influent chemical oxygen demand of wastewater was used. The obtained maximal voltage value (600 mV) has also been compared to literature data. Computational fluid dynamics (CFD) was used to calculate the fluid flow and the exit age distribution of fluid elements in the reactor to explain the obtained experimental results and identify the crucial parameters for the design of bioreactors on an industrial scale.

  20. Efficiency of Calatonia on clinical parameters in the immediate post-surgery period: a clinical study

    Directory of Open Access Journals (Sweden)

    Elaine Ferreira Lasaponari

    2013-09-01

    Full Text Available OBJECTIVE: to assess the efficiency of the Calatonia technique about clinical parameters and pain in the immediate post-surgical phase. METHOD: a randomised study was carried out with 116 patients subjected to a cholecystectomy, by laparoscopy, divided into an experimental group (58 patients and a placebo group (58 patients. The experimental group received the Calatonia technique, while the placebo was only subjected to non-intentional touches. RESULTS: The placebo group and the experimental group were considered homogeneous in terms of the variables: sex, age, physical status classification, duration of surgical procedures and also the time spent recovering in the Post-Anaesthetic Recovery Room. The only variable to show a statistically significant difference was the axillary temperature of the body. In relation to pain, the experimental group showed significant results, and hence it is possible to deduce that the relaxation caused by the Calatonia technique brought some relief of the general situation of pain. CONCLUSION: The application of Calatonia can take up the function of a resource complementary to assistance in the period immediately after surgery. Brazilian Register of Clinical Trials, UTN U1111-1129-9629.