Sample records for vertical wall supports

  1. Wall-Friction Support of Vertical Loads in Submerged Sand and Gravel Columns

    Energy Technology Data Exchange (ETDEWEB)

    Walton, O. R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Vollmer, H. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hepa, V. S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)


    Laboratory studies of the ‘floor-loads’ under submerged vertical columns of sand and/or gravel indicate that such loads can be approximated by a buoyancy-corrected Janssen-silo-theory-like relationship. Similar to conditions in storage silos filled with dry granular solids, most of the weight of the sand or gravel is supported by wall friction forces. Laboratory measurements of the loads on the floor at the base of the water-filled columns (up to 25-diameters tall) indicate that the extra floor-load from the addition of the granular solid never exceeded the load that would exist under an unsupported (wide) bed of submerged sand or gravel that has a total depth corresponding to only two column-diameters. The measured floorloads reached an asymptotic maximum value when the depth of granular material in the columns was only three or four pipe-diameters, and never increased further as the columns were filled to the top (e.g. up to heights of 10 to 25 diameters). The floor-loads were stable and remained the same for days after filling. Aggressive tapping (e.g. hitting the containing pipe on the outside, manually with a wrench up and down the height and around the circumference) could increase (and occasionally decrease) the floor load substantially, but there was no sudden collapse or slumping to a state without significant wall friction effects. Considerable effort was required, repeatedly tapping over almost the entire column wall periphery, in order to produce floor-loads that corresponded to the total buoyancy-corrected weight of granular material added to the columns. Projecting the observed laboratory behavior to field conditions would imply that a stable floor-load condition, with only a slightly higher total floor pressure than the preexisting hydrostatic-head, would exist after a water-filled bore-hole is filled with sand or gravel. Significant seismic vibration (either a large nearby event or many micro-seismic events over an extended period) would likely

  2. Breakwaters with Vertical and Inclined Concrete Walls

    DEFF Research Database (Denmark)

    Burcharth, Hans Falk

    Following the PIANC PTC II working group on Analyses of Rubble Mound Breakwaters it was, in 1991, decided to form Working Group (WG) n° 28 on "Breakwaters with vertical and inclined concrete walls" The scope of the work was to achieve a better understanding of the overall safety aspects...

  3. Reliability Analysis and Optimal Design of Monolithic Vertical Wall Breakwaters

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Burcharth, Hans F.; Christiani, E.


    Reliability analysis and reliability-based design of monolithic vertical wall breakwaters are considered. Probabilistic models of the most important failure modes, sliding failure, failure of the foundation and overturning failure are described . Relevant design variables are identified and relia......Reliability analysis and reliability-based design of monolithic vertical wall breakwaters are considered. Probabilistic models of the most important failure modes, sliding failure, failure of the foundation and overturning failure are described . Relevant design variables are identified...

  4. Reliability Analysis of Geotechnical Failure Modes for Vertical Wall Breakwaters

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Burcharth, H. F.


    Vertical wall breakwaters are usually designed as concrete caissons placed on the top of a rubble mound foundation or a rubble bedding layer. The purpose of the breakwater is usually to protect the area behind the breakwater from being flooded by large waves. The area protected can for example...... be a harbour of small or large importance, an important industrial area or a heavily populated coast line. This implies that vertical wall breakwaters are used under quite different conditions and therefore the consequences of a complete or partial failure also are very different. This implies...

  5. The Turkish Gecko Hemidactylus turcicus Prefers Vertical Walls


    Vogrin, Milan


    In summer 1997 on the island of Pag in Croatia, we studied a selection of perching sites of the Turkish gecko Hemidactylus turcicus. With the transect sampling of 1 hour in 2 days we found 102 geckos. Adults as well as juveniles were founds mostly on vertical walls.

  6. Transient reflectivity on vertically aligned single-wall carbon nanotubes

    NARCIS (Netherlands)

    Galimberti, Gianluca; Ponzoni, Stefano; Ferrini, Gabriele; Hofmann, Stephan; Arshad, Muhammad; Cepek, Cinzia; Pagliara, Stefania


    One-color transient reflectivity measurements are carried out on two different samples of vertically aligned single-wall carbon nanotube bundles and compared with the response recently published on unaligned bundles. The negative sign of the optical response for both samples indicates that the free

  7. A new alternative in vertical barrier wall construction

    Energy Technology Data Exchange (ETDEWEB)

    Rawl, G.F. [Horizontal Technologies Inc., Matlacha, FL (United States)


    A new proprietary vertical barrier wall system has been developed to revolutionize the construction process by eliminating many of the concerns of conventional installation method`s with respect to performance, installation constraints and costs. Vertical barrier walls have been used in the environmental and construction industries for a variety of purposes, usually for cut-off or containment. The typical scenario involves a groundwater contamination problem, in which a vertical barrier wall is utilized to contain or confine the spread of contaminants below the ground surface. Conventional construction techniques have been adequate in many applications, but often fall short of their intended purposes due to physical constraints. In many instances, the economics of these conventional methods have limited the utilization of physical barrier walls. Polywall, the trade name for this new barrier wall technology, was subsequently developed to meet these needs and offer a number of distinct advantages in a variety of scenarios by maximizing confinement and minimizing installation costs. Polywall is constructed from chemically resistant high density polyethylene (HDPE) plastic. It has proven in a half-dozen projects to date to be the most cost-effective and technically sound approach to many containment situations. This paper will cover the development of the technology and will provide a brief synopsis of several installations.

  8. Water Walls for Life Support (United States)

    Flynn, Michael T. (Inventor); Gormly, Sherwin J. (Inventor); Hammoudeh, Mona (Inventor); Richardson, Tra-My Justine (Inventor)


    A method and associated system for processing waste gases, liquids and solids, produced by human activity, to separate (i) liquids suitable for processing to produce potable water, (ii) solids and liquids suitable for construction of walls suitable for enclosing a habitat volume and for radiation shielding, and (iii) other fluids and solids that are not suitable for processing. A forward osmosis process and a reverse osmosis process are sequentially combined to reduce fouling and to permit accumulation of different processable substances. The invention may be used for long term life support of human activity.

  9. Migration of clean and contaminated bubbles near a vertical wall (United States)

    Magnaudet, Jacques; Takemura, Fumio


    The lateral migration of air bubbles rising near a vertical wall in both tap water and low-viscosity silicone oil is studied experimentally over a range of Reynolds number (Re) from 10 to 100. Bubbles rising in water behave as rigid spheres and are repelled from the wall whatever Re, owing to the interaction between the defect flow in their wake and the wall. For such bubbles, the lateral force is correctly predicted by a generalization of the Vasseur & Cox's expression, provided a suitable rescaling taking into account the strength of the vorticity at the bubble surface is introduced. Bubbles rising in silicone oil are hydrodynamically clean and are also repelled from the wall for Re less than 35. In contrast they migrate towards the wall at higher Re, due to the Bernoulli effect predicted by potential flow theory. Knowing the strength of the irrotational dipole associated with the bubble and that of the vorticity at its surface as a function of Re, a unified model predicting the sign reversal of the lateral force is obtained by combining linearly the wake-induced effect and the irrotational mechanism. When bubbles rise very close to the wall, a lubrication effect takes place in the gap, resulting in a repulsive force for small separations. This effect makes the sign of the lateral force acting on high-Re clean bubbles change very close to the wall, which result in the bounce of the bubbles.

  10. A vertical wall in the Whittard Canyon with a novel community assemblage (United States)

    Johnson, Mark; White, Martin; Wilson, Annette; Wuerzberg, Laura; Schwabe, Enrico; Folch, Helka; Allcock, Louise


    We describe a hitherto unreported community from a vertical wall in the Whittard Canyon system on the Atlantic Margin. The wall extended vertically for about 100 m from approximately 750 m depth. We explored the wall with an ROV and discovered an assemblage cominated by large limid bivalves Acesta excavata and deep-water oysters Neopycnodonte zibrowii at very high densities, particularly at overhangs. The assemblage also contained deep-water corals (including solitary corals). It had high numbers of flytrap anemones and had many mobile species associated with it including crustaceans such as Paramola cuvieri and Bathynectes longispina, echinoderms and fishes. We took CTD transects in the area of the wall and beam attenuation indicated nepheloid layers present in the water column. The greatest densities of suspended material at the ROV dive site were at the depth of the wall. We hypothesise that internal waves concentrate suspended sediment at the foot of the vertical wall. This may provide the resources to support the high density of large filter feeders at these depths.

  11. Seismic behavior of semi-supported steel shear walls

    DEFF Research Database (Denmark)

    Jahanpour, A.; Jönsson, J.; Moharrami, H.


    During the recent past decade semi-supported steel shear walls (SSSW) have been introduced as an alternative to the traditional type of steel plate shear walls. In this system the shear wall does not connect directly to the main columns of the building frame; instead it is connected to a pair...... of secondary columns that do not carry vertical gravity loads. In this paper, the interaction between the wall plate and the surrounding frame is investigated experimentally for typical SSSW systems in which the wall-frame has a bending-dominant behavior. Based on the possible storey failure mechanisms...... a simple method is proposed for design of the floor beams. A quasi static cyclic experimental study has been performed in order to investigate the collapse behavior of the wall-plate and surrounding frame. Furthermore the test setup has been developed in order to facilitate standardized cyclic tests...

  12. The Impact of a Deepwater Wave on a Wall with Finite Vertical Extent (United States)

    Wang, An; Duncan, James H.


    The impact of a dispersively focused 2D plunging breaker (average wave frequency 1.15 Hz) on a 2D wall that is 45 cm high and 30 cm thick is studied experimentally. The temporal evolution of the water surface profile upstream of the wall is measured with a cinematic LIF technique using frame rates up to 4,500 Hz. Impact pressures on the wall are measured simultaneously at sample rates up to 900 kHz. The wall is located horizontally 6.41 m from the wave maker in all cases and the submergence of the bottom surface of the wall is varied. It is found that the impact behavior varies dramatically with the wall submergence. When the bottom is submerged by 13.3 cm, a flip-through impact occurs. In this case, the impact evolves without wave breaking and a vertical jet is formed. When the wall is submerged by less than 4.5 cm, small-amplitude components in the wave packet interact with the bottom of the wall before the main crest arrives. Ripples reflected during this interaction modify the behavior of the incoming breaker significantly. When the bottom of the wall is located sufficiently high above the mean water level, the first interaction occurs when the undisturbed wave crest collides with the wall. The highest pressures are observed in this case. The support of the Office of Naval Research is gratefully acknowledged.

  13. Breaking Wave Impact Pressure on a Vertical Wall

    Directory of Open Access Journals (Sweden)

    C. Rajasekaran


    Full Text Available Offshore and coastal structures experience wave impact loads particularly due to breaking waves throughout its design period. In the present paper, an experimental program has been devised to improve our perceptive of the physics and the characteristics of impact pressures due to breaking waves on a vertical wall. The salient features of the study such as model details, breaking wave simulation, the impact and dynamic pressure variation along the depth of the wall are presented. The maximum impact pressure magnitude is found to be of the order of ten times that of the non-breaking dynamic pressure and it always occurred above the still water level for different intensities of breaking waves considered. The minimum pressure rise time is observed to be 0.235 ms.

  14. Scour at the head of a vertical-wall breakwater

    DEFF Research Database (Denmark)

    Sumer, B. Mutlu; Fredsøe, Jørgen


    This paper presents the results of an experimental investigation on the near-bed flow patterns, the bed shear stress amplification and scour around the head of a vertical-wall breakwater, using regular waves. The Keulegan-Carpenter number (KC), based on the diameter of the breakwater head, is found...... to be the major parameter that governs the flow and the equilibrium scour depth. Basic flow structures are identified as function of KC. The scour depth is found to increase with increasing the Keulegan-Carpenter number. The necessary extent of the conventional stone protection is studied. An empirical formula...

  15. Experimental study of soliton interaction with a vertical wall (United States)

    Shurgalina, Ekaterina; Kimmoun, Olivier; Kharif, Christian; Pelinovsky, Efim


    The occurrence of a residual jet in the case of interaction of two large counter propagating solitons was found numerically in the paper [J .Chambarel, C.Kharif , and J.Touboul, Head-on collision of two solitary waves and residual falling jet formation, Nonlin. Processes Geophys., 16, 111-122, 2009] using a Boundary Integral Equation Method (BIEM). This phenomenon occurs for amplitudes of soliton larger than a threshold value (the normalized amplitude of soliton has to be larger than 0.60). We check this effect experimentally and consider soliton interaction with a vertical wall that corresponds to the case of collision of two identical counter propagating solitons. The impact on the wall is compared with the jet found in numerical simulations. The experimental canal is located in Ecole Central de Marseille (France) and has the following dimensions (220*20*40cm). Solitons are generated by a piston wavemaker. Results could be applied to the problem of big wave formation on the coast and on the coastal structures.

  16. Vertical Equilibrium of Sheet Pile Walls with Emphasis on Toe Capacity and Plugging

    DEFF Research Database (Denmark)

    Iversen, Kirsten Malte; Augustesen, Anders Hust; Nielsen, Benjaminn Nordahl

    at the pile toe to fulfil vertical equilibrium. The paper describes a case study of sheet pile walls in Aalborg Clay, and the amount of loads transferred as point loads at the pile toe for free and anchored walls is estimated. A parametric study is made for the free wall with regards to the height...... and the roughness of the wall. Due to limitations of the calculation method, the study of the anchored wall only includes variation of the roughness. For the case study, it is found that the vertical equilibrium is fulfilled for the considered free wall. An anchored wall needs a plug forming at the pile toe...

  17. Transient reflectivity on vertically aligned single-wall carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Galimberti, Gianluca; Ponzoni, Stefano; Ferrini, Gabriele [Interdisciplinary Laboratory for Advanced Materials Physics (i-LAMP) and Dipartimento di Matematica e Fisica, Università Cattolica del Sacro Cuore, I-25121 Brescia (Italy); Hofmann, Stephan [Department of Engineering, University of Cambridge, Cambridge CB3 0FA (United Kingdom); Arshad, Muhammad [Zernike Institute for Advanced Materials, University of Groningen (Netherlands); ICTP, Strada Costiera 11, I-34151 Trieste (Italy); National Centre for Physics Quaid-i-Azam University Islamabad (Pakistan); Cepek, Cinzia [Istituto Officina dei Materiali — CNR, Laboratorio TASC, Area Science Park, Basovizza, I-34149 Trieste (Italy); Pagliara, Stefania, E-mail: [Interdisciplinary Laboratory for Advanced Materials Physics (i-LAMP) and Dipartimento di Matematica e Fisica, Università Cattolica del Sacro Cuore, I-25121 Brescia (Italy)


    One-color transient reflectivity measurements are carried out on two different samples of vertically aligned single-wall carbon nanotube bundles and compared with the response recently published on unaligned bundles. The negative sign of the optical response for both samples indicates that the free electron character revealed on unaligned bundles is only due to the intertube interactions favored by the tube bending. Neither the presence of bundles nor the existence of structural defects in aligned bundles is able to induce a free-electron like behavior of the photoexcited carriers. This result is also confirmed by the presence of non-linear excitonic effects in the transient response of the aligned bundles. - Highlights: • Transient reflectivity measurements on two aligned carbon nanotube samples • Relationship between unalignment and/or bundling and intertube interaction • The bundling is not able to modify the intertube interactions • The presence of structural defects does not affect the intertube interactions • A localized exciton-like behavior has been revealed in these samples.

  18. Simulations of Extreme Wave Runup on a Vertical Wall by Analytic Boussinesq Model

    NARCIS (Netherlands)

    Kurnia, Ruddy


    Wave runup on a vertical wall has both fundamental and practical interest. The wave impact on a structure is an important aspect that must be taken into account in the design of coastal structures. From linear wave theory, it is known that the wave amplitude on a vertical fully reflecting wall is

  19. Lateral resistance of piles near vertical MSE abutment walls. (United States)


    Full scale lateral load tests were performed on eight piles located at various distances behind MSE walls. The objective of the testing was to determine the effect of spacing from the wall on the lateral resistance of the piles and on the force induc...


    National Research Council Canada - National Science Library

    F Jaugsch; M-O Löwner


    ... parliament’s goal of reducing CO2 emissions by 20 % compared to 1990. Although annual radiation on vertical walls is lower than that on roof surfaces, they are larger in area and, therefore may contribute to energy production...

  1. Engineering and Design: Stability of Gravity Walls Vertical Shear

    National Research Council Canada - National Science Library

    Barber, Paul


    This engineer technical letter (ETL) provides guidance for incorporating and calculating a shear force acting along the backs of gravity earth retaining walls within the procedures for analyzing the stability of navigation structures...

  2. Contiguous Pile Wall as a Deep Excavation Supporting System

    Directory of Open Access Journals (Sweden)

    Venkata Ramasubbarao GODAVARTHI


    Full Text Available Providing space for parking, public amenities, etc in multi-storey buildings at town centres has created a need to go deep excavations into ground. Deep excavations are supported by systems like conventional retaining walls, sheet pile walls, braced walls, diaphragm walls and pile walls. This article describes various excavation supporting systems that are in vogue essentially contiguous pile wall and its advantages. A detailed design methodology of an excavation supporting system is furnished in this study. A case study on the Contiguous pile wall retaining system for supporting a deep excavation at a town centre is presented.

  3. Simulation of the electromagnetic wall response to plasma wall-touching kink and vertical modes with application to ITER (United States)

    Atanasiu, Calin; Zakharov, Leonid; Lackner, Karl; Hoelzl, Matthias; Strumberger, Erika


    Realistic simulations of electric current excitation in three-dimensional vessel structures by the plasma touching the walls are necessary to understand plasma disruptions in tokamak. In large tokamaks like ITER, the wall-touching kink modes cause large sideway forces on the vacuum vessel determined by the sharing of asymmetric electric current between the plasma and the wall. Our model covers both eddy currents, excited inductively by vertical modes, and source/sink currents due to current sharing between the plasma and the thin conducting wall. The developed finite element approach calculates the electromagnetic wall response to perturbation of magnetic fields and to current sharing between the plasma and the wall. The current density entering/exiting the wall surface from the plasma and the time derivative of the magnetic vector potential of the plasma are the input values. The magnetic field and the vector potential from the wall currents are returned as output. Our model has been checked against analytical examples of a multiply-connected domain of a real ITER wall.

  4. Controlling the growth of vertically aligned single walled carbon nanotubes from ethanol for electrochemical supercapacitor application

    Energy Technology Data Exchange (ETDEWEB)

    Azam, M.A.; Mohamed, M.A.; Shikoh, E.; Fujiwara, A.; Shimoda, T. [Japan Advanced Inst. of Science and Technology, Ishikawa (Japan)


    Single-walled carbon nanotubes (SWCNTs) have been proven suitable for use as electrodes in electrochemical capacitors (EC). In this study, alcohol catalytic chemical vapor deposition (ACCVD) was used to grow vertically-aligned SWCNTs (VASWCNTs). An aluminium oxide (Al{sub 2}O{sub 3})-supported cobalt (Co) catalyst and high purity ethanol carbon feedstock was used for the growth process. The Al layer and Co thin films were deposited using an electron beam evaporator. CNT growth was optimized using Si/SiO{sub 2} substrates. An atomic force microscope, scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses were used to characterize the synthesis of the catalyst nanoparticles and their subsequent growth. Raman spectrum of the samples demonstrated peaks of radial breathing mode (RBM) from 100 to 250 per cm. Results demonstrated that the CNTs were successfully grown on the conducting metal substrate using the ACCVD process. 4 refs.


    Directory of Open Access Journals (Sweden)

    Kantarzhi Igor' Grigor'evich


    Full Text Available The problem of wave loads on a relatively short wall is related to the issue of the general design of the structure at the stage of its construction, particularly, if the structure is build offshore. The physical nature of interaction between waves and vertical walls that have different lengths is the subject matter of this paper. It is assumed that the wall is absolutely rigid. The comparison of numerical test results and an analytical calculation based on a short wall model is made. As a result, wave forces identified through the employment of the above two models demonstrate their satisfactory convergence. The difference is substantial for longer walls, and it increases along with the increase of the wall length. The conclusion is that a short wall is exposed to the wave load that is not accompanied by any diffraction, therefore, a related method of design may be recommended. Numerical models may be considered as the universal ones.

  6. Bubble detachment and lift-off diameters at a vertical heated wall for subcooled boiling flow

    Energy Technology Data Exchange (ETDEWEB)

    Montout, Michael; Haynes, Pierre-Antoine; Peturaud, Pierre [EDF, R and D Division, Fluid Dynamics, Power Generation and Environnement Department, 6 quai Watier, 78401 Chatou Cedex (France); Colin, Catherine [Institut de Mecanique des Fluides de Toulouse, Allee du Professeur Camille Soula, 31400 Toulouse (France)


    bubble growing on a vertical heating wall, following preceding works from Klausner et al. (1993) and Thorncroft et al. (2001). However, it would be rather complex to implement such a comprehensive approach in a CFD code. Therefore, in a second step, supported simplifications are brought to the force balance model, leading to analytical relations for both detachment and lift-off diameters. An assessment of this 2-step analytical work is made by means of comparisons with existing correlations and experimental data. (authors)

  7. Injection molding of micro pillars on vertical side walls using polyether-ether-ketone (PEEK)

    DEFF Research Database (Denmark)

    Zhang, Yang; Hansen, Hans Nørgaard; Sørensen, Søren


    This paper investigates the replication of microstructures on a vertical wall by PEEK injection molding. A 4-cavity insert was used in the injection molding. Pre-fabricated nickel plates with ø 4 μm micro holes on the surface were glued on vertical walls in the cavities. 3 cavities were coated...... by CrN, TiN and TiB2 respectively, the remaining one was not coated as a reference. The effect of coating was compared via the morphology of the micropillars on the polymer parts. 4000 injection molding cycles were repeated. The roughness of the coated surface was measured. The reasons for the demolding...

  8. Numerical case studies of vertical wall fire protection using water spray

    Directory of Open Access Journals (Sweden)

    L.M. Zhao


    Full Text Available Studies of vertical wall fire protection are evaluated with numerical method. Typical fire cases such as heated dry wall and upward flame spread have been validated. Results predicted by simulations are found to agree with experiment results. The combustion behavior and flame development of vertical polymethylmethacrylate slabs with different water flow rates are explored and discussed. Water spray is found to be capable of strengthening the fire resistance of combustible even under high heat flux radiation. Provided result and data are expected to provide reference for fire protection methods design and development of modern buildings.

  9. Precission plunge milling for angled vertical walls, on three axis machining center (United States)

    Pralea, B.; Nagit, GH


    In this study the authors will construct a type of milling based on the plunge milling and raster milling toolpath strategy, only this time it is not going to be used for roughing but only for finishing vertical and angled surfaces of particular components of injection molds, with the help of a three axis vertical machining center. This particular toolpath strategy designed, with a commercial CAM program, for finishing the vertical and angled walls, offers a better surface roughness, and a better dimensional control (accuracy), both for the milling tool and also for the work piece.

  10. Ship berthing to a vertical quay-wall : Fender forces and ship motion

    NARCIS (Netherlands)

    Fontijn, H.L.


    In this report a mathematical model is formulated which is sufficiently accurate to describe the typical behaviour of a ship berthing to a vertical quay-wall fitted with fenders as well as to determine the response of the fenders themselves. In order to achieve this a three-dimensional set of

  11. Hydrodynamic conditions in front of a vertical wall with an overhanging horizontal cantilever slab (United States)

    Kisacik, Dogan; Ozyurt, Gulizar; Troch, Peter


    Transforming wave heights from offshore to the shoreline is the first step of any coastal engineering work. Wave breaking is analyzed to understand hydrodynamic conditions. For vertical breakwaters and sea walls, wave reflection is an important process that affects the determination of the wave height. Many of the design formulas presented in the literature depend on empirical studies based on the structures tested. In this study, the hydrodynamic conditions in front of a vertical wall with an overhanging horizontal cantilever slab with a foreshore slope of 1/20 are determined experimentally under regular wave conditions to assess the applicability of the formulas of Goda (2000) for predicting the nearshore wave height and breaker index equation (Goda, 2010). The selection of wave measurements used to determine the design wave height, the reflection coefficients, and wave breaking is also analyzed, and the reflection equations are derived from the dataset covering different breaker types. Small-scale tests show that the incident wave height is a good representative of the design wave height and that the values predicted by Goda are in good agreement with actual measurements. However, the predicted H max values are overestimated. In addition, the inception of the wave breaking point is postponed because of the reflection and/or turbulence left over from preceding waves, which is an effect of the vertical wall. At higher water levels, the effect of the vertical wall on the inception point becomes more significant.


    Directory of Open Access Journals (Sweden)

    F. Jaugsch


    Full Text Available In urban areas, solar energy is one promising source of renewable energy to achieve the EU parliament’s goal of reducing CO2 emissions by 20 % compared to 1990. Although annual radiation on vertical walls is lower than that on roof surfaces, they are larger in area and, therefore may contribute to energy production. On the other hand, the modelling of shadowing effects is cost intensive in an complex urban environment. Here we present a method for the calculation of solar potential on vertical walls for simple 2D maps with additional building height information. We introduced observer point columns that enable a fast decision whether a whole vertical set of observer points is illuminated or not. By the introduction of a maximum shade length, we reduce processing time in ArcGIS. 206,291 points of 130 buildings have been analysed in time steps of 15 minutes resulting in 15 769 pairs of solar angles. Results disprove the potential of vertical walls serving to fill the winter gap of roof mounted solar energy plants. Best wall orientation for the deployment of solar panels are west and east in summer, whereas it is southeast in winter.

  13. The effect of non-linear wave in front of vertical wall using bi ...

    African Journals Online (AJOL)

    of waves in front of a vertical wall are examined, using the new theoretical approach of a bi-parametric distribution, proposed by Ejinkonye [1] to investigate the effect of nonlinearity for the mechanics of the sea waves. The most probable value of the wave steepness is assumed to be = 0.055. From the subsequent calculation ...

  14. Production of vertical arrays of small diameter single-walled carbon nanotubes (United States)

    Hauge, Robert H; Xu, Ya-Qiong


    A hot filament chemical vapor deposition method has been developed to grow at least one vertical single-walled carbon nanotube (SWNT). In general, various embodiments of the present invention disclose novel processes for growing and/or producing enhanced nanotube carpets with decreased diameters as compared to the prior art.

  15. Application of Reliability Analysis for Optimal Design of Monolithic Vertical Wall Breakwaters

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Sørensen, John Dalsgaard; Christiani, E.


    Reliability analysis and reliability-based design of monolithic vertical wall breakwaters are considered. Probabilistic models of some of the most important failure modes are described. The failures are sliding and slip surface failure of a rubble mound and a clay foundation. Relevant design vari...

  16. Experimental Study on the Seismic Performance of Recycled Concrete Brick Walls Embedded with Vertical Reinforcement. (United States)

    Cao, Wanlin; Zhang, Yongbo; Dong, Hongying; Zhou, Zhongyi; Qiao, Qiyun


    Recycled concrete brick (RCB) is manufactured by recycled aggregate processed from discarded concrete blocks arising from the demolishing of existing buildings. This paper presents research on the seismic performance of RCB masonry walls to assess the applicability of RCB for use in rural low-rise constructions. The seismic performance of a masonry wall is closely related to the vertical load applied to the wall. Thus, the compressive performance of RCB masonry was investigated firstly by constructing and testing eighteen RCB masonry compressive specimens with different mortar strengths. The load-bearing capacity, deformation and failure characteristic were analyzed, as well. Then, a quasi-static test was carried out to study the seismic behavior of RCB walls by eight RCB masonry walls subjected to an axial compressive load and a reversed cyclic lateral load. Based on the test results, equations for predicting the compressive strength of RCB masonry and the lateral ultimate strength of an RCB masonry wall were proposed. Experimental values were found to be in good agreement with the predicted values. Meanwhile, finite element analysis (FEA) and parametric analysis of the RCB walls were carried out using ABAQUS software. The elastic-plastic deformation characteristics and the lateral load-displacement relations were studied.

  17. Tsunami Wave Run-up on a Vertical Wall in Tidal Environment (United States)

    Didenkulova, Ira; Pelinovsky, Efim


    We solve analytically a nonlinear problem of shallow water theory for the tsunami wave run-up on a vertical wall in tidal environment. Shown that the tide can be considered static in the process of tsunami wave run-up. In this approximation, it is possible to obtain the exact solution for the run-up height as a function of the incident wave height. This allows us to investigate the tide influence on the run-up characteristics.

  18. Effects of vertical wall and tetrapod weights on wave overtopping in rubble mound breakwaters under irregular wave conditions

    Directory of Open Access Journals (Sweden)

    Sang Kil Park


    Full Text Available Rubble mound breakwaters protect the coastal line against severe erosion caused by wave action. This study examined the performance of different sizes and properties (i.e. height of vertical wall and tetrapod size of rubble mound breakwaters on reducing the overtopping discharge. The physical model used in this study was derived based on an actual rubble mound in Busan Yacht Harbor. This research attempts to fill the gap in practical knowledge on the combined effect of the armor roughness and vertical wall on wave overtopping in rubble mound breakwaters. The main governing parameters used in this study were the vertical wall height, variation of the tetrapod weights, initial water level elevation, and the volume of overtopping under constant wave properties. The experimental results showed that the roughness factor differed according to the tetrapod size. Furthermore, the overtopping discharge with no vertical wall was similar to that with relatively short vertical walls (γν = 1. Therefore, the experimental results highlight the importance of the height of the vertical wall in reducing overtopping discharge. Moreover, a large tetrapod size may allow coastal engineers to choose a shorter vertical wall to save cost, while obtaining better performance.

  19. Effects of vertical wall and tetrapod weights on wave overtopping in rubble mound breakwaters under irregular wave conditions

    Directory of Open Access Journals (Sweden)

    Park Sang Kil


    Full Text Available Rubble mound breakwaters protect the coastal line against severe erosion caused by wave action. This study examined the performance of different sizes and properties (i.e. height of vertical wall and tetrapod size of rubble mound breakwaters on reducing the overtopping discharge. The physical model used in this study was derived based on an actual rubble mound in Busan Yacht Harbor. This research attempts to fill the gap in practical knowledge on the combined effect of the armor roughness and vertical wall on wave overtopping in rubble mound breakwaters. The main governing parameters used in this study were the vertical wall height, variation of the tetrapod weights, initial water level elevation, and the volume of overtopping under constant wave properties. The experimental results showed that the roughness factor differed according to the tetrapod size. Furthermore, the overtopping discharge with no vertical wall was similar to that with relatively short vertical walls ( 1 γv = 1. Therefore, the experimental results highlight the importance of the height of the vertical wall in reducing overtopping discharge. Moreover, a large tetrapod size may allow coastal engineers to choose a shorter vertical wall to save cost, while obtaining better performance.

  20. An experimental investigation of the seismic behavior of semi-supported steel shear walls

    DEFF Research Database (Denmark)

    Jahanpour, Alireza; Jönsson, Jeppe; Moharrami, H.


    . These half scale models represent an intermediate storey in a multi-storey steel frame. Hysteresis loops traced from the load deflection curves of these tests have an “S” shape and dissipate energy well. The system has an acceptable level of ductility, which enables its use as a lateral earthquake load......A semi-supported steel shear wall (SSSW) has been developed in the recent decade, the steel wall is connected to secondary columns that do not carry vertical loads and are used to enable the plate to enter into the post buckling region and develop a tension field. Theoretical research...

  1. Dynamics of the collision of a vortex ring with a vertical heated wall (United States)

    Gelderblom, G.; Palacios-Morales, C. A.; Zenit, R.; Solorio-Ordaz, F. J.


    We study the dynamics of the impact of a vortex ring with a vertical heated plate (at constant temperature). Laminar vortex rings were generated with a piston cylinder arrangement. The vertical wall is heated by a thermal bath which is held at constant temperature producing a laminar and stable thermal boundary layer. Measurements of the 2D velocity field were obtained with a PIV technique. The experimental results for the isothermal case are in agreement with previous investigations reported in the literature. To avoid azimuthal instabilities, we mainly conducted experiments for L /D0 = 1 (where L is the piston displacement and D0 is the cylinder inner diameter) with different wall temperatures and vortex translation velocities. For this case, secondary vortices were not observed. Using ink visualization we observed the evolution of the vortex shape. The initial circular shape evolves into a ``cat head'' shape after reaching the wall. The top and bottom regions of the vortex reduce and increase their vorticity, respectively. The sides are stretched and convected. An analysis of the different mechanisms leading to this shape evolution is presented and discussed.

  2. Near-Surface Boundary Layer Turbulence Along a Horizontally-Moving, Surface-Piercing Vertical Wall

    CERN Document Server

    Washuta, Nathan; Duncan, James H


    The complex interaction between turbulence and the free surface in boundary layer shear flow created by a vertical surface-piercing wall is considered. A laboratory-scale device was built that utilizes a surface-piercing stainless steel belt that travels in a loop around two vertical rollers, with one length of the belt between the rollers acting as a horizontally-moving flat wall. The belt is accelerated suddenly from rest until reaching constant speed in order to create a temporally-evolving boundary layer analogous to the spatially-evolving boundary layer that would exist along a surface-piercing towed flat plate. Surface profiles are measured with a cinematic laser-induced fluorescence system and sub-surface velocity fields are recorded using a high-speed planar particle image velocimetry system. It is found that the belt initially travels through the water without creating any significant waves, before the free surface bursts with activity close to the belt surface. These free surface ripples travel away...

  3. Oblique wave motion over multiple submerged porous bars near a vertical wall (United States)

    Zhao, Yang; Liu, Yong; Li, Huajun; Chang, Anteng


    This study examines oblique wave motion over multiple submerged porous bars in front of a vertical wall. Based on linear potential theory, an analytical solution for the present problem is developed using matched eigenfunction expansions. A complex dispersion relation is adopted to describe the wave elevation and energy dissipation over submerged porous bars. In the analytical solution, no limitations on the bar number, bar size, and spacing between adjacent bars are set. The convergence of the analytical solution is satisfactory, and the correctness of the analytical solution is confirmed by an independently developed multi-domain BEM (boundary element method) solution. Numerical examples are presented to examine the reflection and transmission coefficients of porous bars, C R and C T , respectively, for engineering applications. The calculation results show that when the sum of widths for all the porous bars is fixed, increasing the bar number can significantly improve the sheltering function of the bars. Increasing the bar height can cause more wave energy dissipation and lower C R and C T . The spacing between adjacent bars and the spacing between the last bar and the vertical wall are the key parameters affecting C R and C T . The proposed analytical method may be used to analyze the hydrodynamic performance of submerged porous bars in preliminary engineering designs.

  4. Tuning vertical alignment and field emission properties of multi-walled carbon nanotube bundles (United States)

    Sreekanth, M.; Ghosh, S.; Srivastava, P.


    We report the growth of vertically aligned carbon nanotube bundles on Si substrate by thermal chemical vapor deposition technique. Vertical alignment was achieved without any carrier gas or lithography-assisted deposition. Growth has been carried out at 850 °C for different quantities of solution of xylene and ferrocene ranging from 2.25 to 3.00 ml in steps of 0.25 ml at a fixed concentration of 0.02 gm (ferrocene) per ml. To understand the growth mechanism, deposition was carried out for different concentrations of the solution by changing only the ferrocene quantity, ranging from 0.01 to 0.03 gm/ml. A tunable vertical alignment of multi-walled carbon nanotubes (CNTs) has been achieved by this process and examined by scanning and transmission electron microscopic techniques. Micro-crystalline structural analysis has been done using Raman spectroscopy. A systematic variation in field emission (FE) current density has been observed. The highest FE current density is seen for the film grown with 0.02 gm/ml concentration, which is attributed to the better alignment of CNTs, less structural disorder and less entanglement of CNTs on the surface. The alignment of CNTs has been qualitatively understood on the basis of self-assembled catalytic particles.


    Directory of Open Access Journals (Sweden)

    Tran Long Giang


    Full Text Available Construction of breakwater structures of modern seaports requires computational models describing interaction of waves with structural elements of ports. The model should be based on numerical hydrodynamic models that contemplate all constituents of interaction between waves and structures, including those at various stages of construction. The above model makes it possible to have construction works performed in accordance with the pre-developed plan. Experimentalresearch of the behaviour of breakwater structures is to be conducted in laboratories. A scaled natural model is to be used for the above purpose to verify the model behaviour. The authors consider the methodology and results of experiments involving models of wave loads produced on vertical breakwater structures at various stages of their construction. On the basis of the experiments conducted by the authors, it is discovered that the value of the total wave force, that the vertical wall is exposed to, increases along with the wall length in the event of a constant wave mode, which is natural. However, the per-meter value of the wave force increases along with the increase in the length of the wall until it reaches the value of the length of a transverse obstacle divided by the length of waves equal to 0.28; thereafter, the wave force goes down. The authors assume that this phenomenon is caused by the change in the nature of interaction between waves and an obstacle and a transition from a diffraction-free flow to a diffraction flow. The authors believe that further researches are necessary to explore the phenomenon.

  6. Application of Support Vector Machines for Estimating Wall Parameters in Through-Wall Radar Imaging

    Directory of Open Access Journals (Sweden)

    Hua-Mei Zhang


    Full Text Available In through-wall radar imaging (TWRI, ambiguities in wall characteristics including the thickness and the relative permittivity will distort the image and shift the imaged target position. To quickly and accurately estimate the wall parameters, an approach based on a support vector machine (SVM is proposed. In TWRI problem, the nonlinearity is embodied in the relationship between backscatter data and the wall parameters, which can be obtained through the SVM training process. Measurement results reveal that once the training phase is completed, the technique only needs no more than one second to estimate wall parameters with acceptable errors. Then through-wall images are reconstructed using a back-projection (BP algorithm by a finite-difference time-domain (FDTD simulation. Noiseless and noisy measurements are discussed; the simulation results demonstrate that noisy contamination has little influence on the imaging quality. Furthermore, the feasibility and the validity are tested by a more realistic situation. The results show that high-quality and focused images are obtained regardless of the errors in the wall parameter estimates.

  7. Wave Loading and Overtopping on Vertical Wall Breakwaters in Multidirectional Breaking Seas

    DEFF Research Database (Denmark)

    Kofoed, Jens Peter; Grønbech, J.; Hald, Tue


    The present paper concerns the results and findings of a physical study on wave impacts on vertical caisson breakwaters situated in irregular, multidirectional breaking seas. The study has taken place as part of the framework programme "Dynamics of Structures" financially supported by the Danish...... Technical Research Council, during the period of January 97 to December 97. The test were carried out in the 3D wave basin at the Hydraulics and Coastal Engineering Laboratory, Aalborg University....

  8. Root growth of perennials in vertical growing media for use in green walls

    DEFF Research Database (Denmark)

    Jørgensen, Lars; Dresbøll, Dorte Bodin; Thorup-Kristensen, Kristian


    The vertical orientation of green walls causes a risk of uneven water distribution within the growing medium, and thereby stress on the plant roots. Therefore it was studied how the root and top growth of different species were affected by the water holding characteristics of the growing media...... distribution was registered over 52 days and the activity of individual root systems was studied via 15N uptake and plant parameters were measured. The water holding characteristics of the growing media was determined on a sandbox. From day 21 and throughout the experiment, the plants growing in the coir...... uptake was higher for plants grown in coir than rockwool. The coir medium showed a more gradual water release with increasing tension than either of the rockwool media, corresponding to the water content measured locally in the boxes. The results confirmed that the growing media affect root...

  9. Extensive chest wall tissue loss and its management by vertical rectus abdominis myocutaneous flap

    Directory of Open Access Journals (Sweden)

    Sandip Kanti Basu


    Full Text Available Extensive electric burn around the chest in children is rare and this type of injury always poses a great challenge for its management. A 12-year-old male child with extensive electric burn of the chest wall was admitted to hospital. It was a neglected case of 9 days old burn; the young boy was in critical condition having systemic features of toxemia with widespread necrosis of the skin, subcutaneous tissues, and muscles along with exposed bones (ribs and sternum with the risk of impending rupture of pleura through the exposed intercostal spaces. After initial resuscitation, a thorough debridement of all necrotic tissues was done. Thereafter, a superiorly based vertical rectus abdominis myocutaneous flap was harvested to cover the exposed bones and intercostal spaces. The remaining raw areas were skin grafted. The child made an excellent recovery with good outcome.

  10. Effects of interfaces on nano-friction of vertically aligned multi-walled carbon nanotube arrays

    Energy Technology Data Exchange (ETDEWEB)

    Lou, J. [Department of Mechanical Engineering and Materials Science, Rice University, Houston, TX 77005 (United States)], E-mail:; Kim, K.-S. [Division of Engineering, Brown University, Providence, RI 02912 (United States)


    Sliding friction properties of vertically aligned multi-walled carbon nanotube (VAMWNT) arrays have been investigated in current study in a quantitative manner. The VAMWNT arrays have been fabricated on an anodic aluminum oxide template by chemical vapor deposition at 650 deg. C. Friction force was measured in air by a modified atomic force microscopy (AFM) cantilever-bead assembly with 15 {mu}m diameter borosilicate sphere attached to the end of the regular AFM cantilever. Quantitative measurements were achieved by using a novel in situ calibration methods recently developed based on diamagnetic levitation [Q. Li, K.-S. Kim, A. Rydberg, Rev. Sci. Instrum. 77 (2006) 065105-1-13]. The effects of different interfaces were studied using both cantilever-bead assembly coated with and without Al thin layer coatings. A reverse stick-slip behavior was observed in the current system as compared to the normal stick-slip behavior found in the literature.

  11. In-vitro detection of artificial caries on vertical dental cavity walls using infrared photothermal radiometry and modulated luminescence (United States)

    Kim, Jungho; Mandelis, Andreas; Abrams, Stephen H.; Vu, Jaclyn T.; Amaechi, Bennett T.


    The main objective of the study was to investigate the ability of frequency-domain photothermal radiometry (PTR) and modulated luminescence (LUM) to detect secondary caries lesions on the walls of restorations (wall lesions). Changes in experimental PTR-LUM signals due to sequential demineralization on entire vertical walls of sectioned tooth samples were investigated. In addition, transverse micro-radiography (TMR) analysis (used as a gold standard) was conducted to measure the degree of demineralization that occurred in each sample. Statistical correlation between TMR results and PTR-LUM signals was determined using Pearson's correlation coefficient. LUM signals were found to be dominated by the scattered component of the incident laser beam. The more clinically relevant cases of localized demineralization and remineralization on vertical walls were also investigated to examine whether PTR-LUM signals are sensitive to demineralization and remineralization of much smaller areas. The overall results demonstrated that PTR-LUM is sensitive to progressive demineralization and remineralization on vertical walls of sectioned tooth samples.

  12. Determination of strength behaviour of slope supported by vegetated crib walls using centrifuge model testing (United States)

    Sudan Acharya, Madhu


    The crib retaining structures made of wooden/bamboo logs with live plants inside are called vegetative crib walls which are now becoming popular due to their advantages over conventional civil engineering walls. Conventionally, wooden crib walls were dimensioned based on past experiences. At present, there are several guidelines and design standards for machine finished wooden crib walls, but only few guidelines for the design and construction of vegetative log crib walls are available which are generally not sufficient for an economic engineering design of such walls. Analytical methods are generally used to determine the strength of vegetated crib retaining walls. The crib construction is analysed statically by satisfying the condition of static equilibrium with acceptable level of safety. The crib wall system is checked for internal and external stability using conventional monolithic and silo theories. Due to limitations of available theories, the exact calculation of the strength of vegetated wooden/bamboo crib wall cannot be made in static calculation. Therefore, experimental measurements are generally done to verify the static analysis. In this work, a model crib construction (1:20) made of bamboo elements is tested in the centrifuge machine to determine the strength behaviour of the slope supported by vegetated crib retaining wall. A geotechnical centrifuge is used to conduct model tests to study geotechnical problems such as the strength, stiffness and bearing capacity of different structures, settlement of embankments, stability of slopes, earth retaining structures etc. Centrifuge model testing is particularly well suited to modelling geotechnical events because the increase in gravitational force creates stresses in the model that are equivalent to the much larger prototype and hence ensures that the mechanisms of ground movements observed in the tests are realistic. Centrifuge model testing provides data to improve our understanding of basic mechanisms

  13. Optical properties of ordered vertical arrays of multi-walled carbon nanotubes from FDTD simulations. (United States)

    Bao, Hua; Ruan, Xiulin; Fisher, Timothy S


    A finite-difference time-domain (FDTD) method is used to model thermal radiative properties of vertical arrays of multi-walled carbon nanotubes (MWCNT). Individual CNTs are treated as solid circular cylinders with an effective dielectric tensor. Consistent with experiments, the results confirm that CNT arrays are highly absorptive. Compared with the commonly used Maxwell-Garnett theory, the FDTD calculations generally predict larger reflectance and absorbance, and smaller transmittance, which are attributed to the diffraction and scattering within the cylinder array structure. The effects of volume fraction, tube length, tube distance, and incident angle on radiative properties are investigated systematically. Low volume fraction and long tubes are more favorable to achieve low reflectance and high absorbance. For a fixed volume fraction and finite tube length, larger periodicity results in larger reflectance and absorbance. The angular dependence studies reveal an optimum incident angle at which the reflectance can be minimized. The results also suggest that an even darker material could be achieved by using CNTs with good alignment on the top surface.

  14. Influence of the Pectoralis Major Muscle Sling in Chest Wall-Based Flap Suspension After Vertical Mammaplasty: Ten-Year Follow-Up. (United States)

    Graf, Ruth; Ricardo Dall Oglio Tolazzi, André; Balbinot, Priscilla; Pazio, André; Miguel Valente, Pedro; da Silva Freitas, Renato


    The pectoralis muscle sling has proven to be a suitable alternative technique for long-term results in breast parenchyma suspension. Although the pectoralis muscle sling has been subjectively observed to reduce the bottoming-out effect with a bipedicled muscle flap (muscular loop), there has not been a study to objectively or numerically prove it. This study aimed to radiologically evaluate the influence of a pectoralis muscle sling in supporting the chest wall-based flap after a vertical breast-reduction technique. Twenty-one female patients underwent a vertical breast reduction with the chest wall-based flap and were randomly divided into two subgroups. Ten patients were in subgroup (S), which consisted of patients with a muscle sling. Eleven patients without the muscle sling technique were assigned as a control group (C). Periodic radiological examinations were performed at 1, 3, 6, and 12 months and then at 10 years postoperatively to analyze the breast flap and any migration with respect to three titanium clips placed intraoperatively on the chest wall parenchyma flap. Patients in subgroup S had a significantly higher difference in migration of the chest wall-based flaps between the first day and 10 years postoperatively when compared with patients in subgroup C (P follow-up, there were changes in chest wall-based flap bottoming-out in patients in whom a pectoralis major muscle sling was utilized compared with those patients without it. Thus, a pectoralis major muscle sling seems to provide greater and longer-lasting support to the flap position on the patient's chest. 2 Therapeutic. © 2016 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission:

  15. The laboratory investigation of surface envelope solitons: reflection from a vertical wall and collisions of solitons (United States)

    Slunyaev, Alexey; Klein, Marco; Clauss, Günther F.


    Envelope soliton solutions are key elements governing the nonlinear wave dynamics within a simplified theory for unidirectional weakly modulated weakly nonlinear wave groups on the water surface. Within integrable models the solitons preserve their structure in collisions with other waves; they do not disperse and can carry energy infinitively long. Steep and short soliton-like wave groups have been shown to exist in laboratory tests [1] and, even earlier, in numerical simulations [2, 3]. Thus, long-living wave groups may play important role in the dynamics of intense sea waves and wave-structure interactions. The solitary wave groups may change the wave statistics and can be taken into account when developing approaches for the deterministic forecasting of dangerous waves, including so-called rogue waves. An experimental campaign has been conducted in the wave basin of the Technical University of Berlin on simulations of intense solitary wave groups. The first successful experimental observation of intense envelope solitons took place in this facility [1]. The new experiments aimed at following main goals: 1) to reproduce intense envelope solitons with different carrier wave lengths; 2) to estimate the rate of envelope soliton dissipation; 3) to consider the reflection of envelope solitons on a vertical wall; 4) to consider head-on collisions of envelope solitons, and 5) to consider overtaking interactions of envelope solitons. Up to 9 wave gauges were used in each experimental run, which enabled registration of the surface movement at different distances from the wavemaker, at different locations across the wave flume and near the wall. Besides surface displacements, the group envelope shapes were directly recorded, with use of phase shifts applied to the modulated waves generated by the wavemaker. [1] A. Slunyaev, G.F. Clauss, M. Klein, M. Onorato, Simulations and experiments of short intense envelope solitons of surface water waves. Phys. Fluids 25, 067105

  16. Support schemes and vertical integration - who skims the cream?

    DEFF Research Database (Denmark)

    Ropenus, Stephanie; Jensen, Stine Grenaa


    This paper examines how the effectiveness of feed-in tariffs for distributed generators, producing renewable electricity, depends on industry structure, i.e., vertical integration vs. unbundling. A stylized analytical model with a monopolist and a competitive fringe (distributed generators) will ...

  17. Numerical heat transfer in a cavity with a solar control coating deposited to a vertical semitransparent wall (United States)

    Alvarez, G.; Estrada, C. A.


    A transient two-dimensional computational model of combined natural convection, conduction, and radiation in a cavity with an aspect ratio of one, containing air as a laminar and non-participating fluid, is presented. The cavity has two opaque adiabatic horizontal walls, one opaque isothermal vertical wall, and an opposite semitransparent wall, which consists of a 6-mm glass sheet with a solar control coating of SnS-CuxS facing the cavity. The semitransparent wall also exchanges heat by convection and radiation from its external surface to the surroundings and allows solar radiation pass through into the interior of the cavity. The momentum and energy equations in the transient state were solved by finite differences using the alternating direction implicit (ADI) technique. The transient conduction equation and the radiative energy flux boundary conditions are coupled to these equations. The results in this paper are limited to the following conditions: 104Gr106, an isothermal vertical cold wall of 21°C, outside air temperatures in the range 30°CT040°C and incident solar radiation of AM2 (750 W m-2) normal to the semitransparent wall. The model allows calculation of the redistribution of the absorbed component of solar radiation to the inside and outside of the cavity. The influences of the time step and mesh size were considered. Using arguments of energy balance in the cavity, it was found that the percentage difference was less than 4 per cent, showing a possible total numerical error less than this number. For Gr=106 a wave appeared in the upper side of the cavity, suggesting the influence of the boundary walls over the air flow inside the cavity. A Nusselt number correlation as a function of the Rayleigh number is presented. Copyright

  18. Numerical thermal analysis of the vertical external partition made as the frame thin-walled steel structure

    Directory of Open Access Journals (Sweden)

    Major Maciej


    Full Text Available The article presents numerical thermal analysis of the vertical external partitions made in the lightweight steel framing technology. Steel posts that perform the structural role lead to the formation of linear thermal bridges and have a negative effect on the level of thermal transmittance U. Therefore, optimal solutions are being explored for such technologies. One of the solutions is to use perforated Thermo sections. The effect of perforated Thermo sections on energy loss was verified through comparison to the wall made of solid sections. Furthermore, the calculations analysed the effect of linear thermal bridges that are formed on wall connections in the corner. Computer simulation was employed to emphasize the significant differences in the temperature distribution in both analysed wall structures that resulted from constructional solutions.

  19. A vertical wall dominated by Acesta excavata and Neopycnodonte zibrowii, part of an undersampled group of deep-sea habitats.

    Directory of Open Access Journals (Sweden)

    Mark P Johnson

    Full Text Available We describe a novel biotope at 633 to 762 m depth on a vertical wall in the Whittard Canyon, an extensive canyon system reaching from the shelf to the deep sea on Ireland's continental margin. We explored this wall with an ROV and compiled a photomosaic of the habitat. The assemblage contributing to the biotope was dominated by large limid bivalves, Acesta excavata (mean shell height 10.4 cm, and deep-sea oysters, Neopycnodonte zibrowii, at high densities, particularly at overhangs. Mean density of N. zibrowii increased with depth, with densities of the most closely packed areas of A. excavata also increasing with depth. Other taxa associated with the assemblage included the solitary coral Desmophyllum dianthus, cerianthid anemones, comatulid crinoids, the trochid gastropod Margarites sp., the portunid crab Bathynectes longispina and small fish of the family Bythitidae. The scleractinian coral Madrepora oculata, the pencil urchin Cidaris cidaris and a species of Epizoanthus were also common. Prominent but less abundant species included the flytrap anemone Actinoscyphia saginata, the carrier crab Paramola cuvieri, and the fishes Lepidion eques and Conger conger. Observations of the hydrography of the canyon system identified that the upper 500 m was dominated by Eastern North Atlantic Water, with Mediterranean Outflow Water beneath it. The permanent thermocline is found between 600 and 1000 m depth, i.e., in the depth range of the vertical wall and the dense assemblage of filter feeders. Beam attenuation indicated nepheloid layers present in the canyon system with the greatest amounts of suspended material at the ROV dive site between 500 and 750 m. A cross-canyon CTD transect indicated the presence of internal waves between these depths. We hypothesise that internal waves concentrate suspended sediment at high concentrations at the foot of the vertical wall, possibly explaining the large size and high density of filter-feeding molluscs.

  20. CFD Calculations of the Air Flow Along a Cold Vertical Wall with an Obstacle

    DEFF Research Database (Denmark)

    Svidt, Kjeld; Heiselberg, Per

    This paper deals with the ability of Computational Fluid Dynamics to predict downdraught at a plane wall and at a wall with large obstacles. Quite simple boundary conditions were used in this study. Predictions of the main flow characteristics and the velocity levels in the occupied zone showed...

  1. Study on prevention of spread of vertical fire along finishing materials for external wall of high-rise buildings

    Directory of Open Access Journals (Sweden)

    Yoo Yong Ho


    Full Text Available Although there are laws in the Korea Building Act relating to exterior finishing materials, fireproof structures and fire-stop of curtain wall structures, the standards relating to and test methods on securing detailed fire safety functions for exterior materials of all buildings including high-rise buildings have not been prepared. This is due to the fact that test methods and standards to quantitatively evaluate the vertical fire spread of the exterior material of buildings do not exist. In addition, while semi non-combustible materials or non-combustible materials are required to be used to prevent fire spread in buildings which exceed 30-stories, it is necessary to review the standards and regulations in cases where fire blocking systems, capable of preventing the vertical fire spread within the curtain wall, are installed to consider permitting the utilization of fire retardant material following an assessment of the construction characteristics of high-rise buildings. The functional evaluation standards and test methods on the vertical fire spread introduced in this study will be a more effective method for performing evaluations to prevent fire spread compared to the currently utilized method of performing small scale tests.

  2. Phase change of First Wall in Water-Cooled Breeding Blankets of K-DEMO for Vertical

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Geon Woo; Lee, Jeong Hun; Cho, Hyoung Kyu; Park, Goon Cherl [Seoul National University, Seoul (Korea, Republic of); Im, Ki Hak [NFRI, Daejeon (Korea, Republic of)


    The purpose of this study is to simulate thermal-hydraulic behavior of a single blanket module when plasma disruption occurs. Plasma disruptions, such as vertical displacement events (VDE), with high heat flux can cause melting and vaporization of plasma facing materials and also burnout of coolant channels. The thermal design, evaluation and validation have been performed in order to establish the conceptual design guidelines of the water-cooled breeding blanket for the K-DEMO reactor. As a part of the NFRI research, Seoul National University (SNU) is conducting transient thermal-hydraulic analysis to confirm the integrity of blanket system for plasma disruption events. Vertical displacement events (VDE) with high heat flux can cause melting and vaporization of plasma facing materials (PFCs) and also burnout of coolant channels. In order to simulate melting of first wall in blanket module when VDE occurs, one-dimensional heat conduction equations were solved numerically with modification of the specific heat of the first wall materials using effective heat capacity method. Temperature profiles in first wall for VDE are shown in fig 7 - 9. At first, temperature of tungsten rapidly raised and even exceeded its melting temperature. When VDE just ended at 0.1 second, 0.83 mm thick of tungsten melted. But the other materials including vanadium and RAFM didn't exceed their melting temperatures after 500 seconds.

  3. Vertical Alignment of Single-Walled Carbon Nanotubes on Nanostructure Fabricated by Atomic Force Microscope

    National Research Council Canada - National Science Library

    Lee, Haiwon


    This project focused on the behavior of single-wall carbon nanotubes (SWCNTs) in the electrophoresis cells and aligned growth of SWCNTs by thermal chemical vapor deposition on selectively deposited metallic nanoparticle...

  4. Cytocompatibility studies of vertically-aligned multi-walled carbon nanotubes: Raw material and functionalized by oxygen plasma

    Energy Technology Data Exchange (ETDEWEB)

    Lobo, A.O., E-mail: [Laboratorio Associado de Sensores e Materiais, INPE, Sao Jose dos Campos/SP (Brazil); Instituto Tecnologico de Aeronautica, ITA, Sao Jose dos Campos/SP (Brazil); Laboratorio de Nanotecnologia Biomedica, Universidade do Vale do Paraiba, Sao Jose dos Campos/SP (Brazil); Corat, M.A.F. [Centro Multidisciplinar para Investigacao Biologica na Area da Ciencia em Animais de Laboratorio, CEMIB, UNICAMP, Campinas/SP (Brazil); Antunes, E.F. [Laboratorio Associado de Sensores e Materiais, INPE, Sao Jose dos Campos/SP (Brazil); Instituto Tecnologico de Aeronautica, ITA, Sao Jose dos Campos/SP (Brazil); Ramos, S.C. [Instituto Tecnologico de Aeronautica, ITA, Sao Jose dos Campos/SP (Brazil); Pacheco-Soares, C. [Laboratorio de Dinamica de Compartimentos Celulares, UNIVAP, Sao Jose dos Campos/SP (Brazil); and others


    It was presented a strong difference on cell adhesion and proliferation of functionalized vertically-aligned multi-walled carbon nanotube (VACNT) scaffolds compared to raw-VACNT. Biocompatibility in vitro tests were performed on raw-VACNT after superficial modification by oxygen plasma, which changes its superhydrophobic character to superhydrophilic. Two cytocompatibility tests were applied: 1) total lactate dehydrogenase colorimetric assay for the study of proliferating cells; and 2) cellular adhesion by scanning electron microscopy. Results showed that superhydrophilic VACNT scaffolds stimulate cell growth with proliferation up to 70% higher than normal growth of cell culture.

  5. Nanocomposites of vertically aligned single-walled carbon nanotubes by magnetic alignment and polymerization of a lyotropic precursor. (United States)

    Mauter, Meagan S; Elimelech, Menachem; Osuji, Chinedum O


    We demonstrate a novel path for the fabrication of thin-film polymer nanocomposites containing vertically aligned single-walled carbon nanotubes (SWNTs). Liquid crystal mesophases of hexagonally packed cylindrical micelles orient with their long axes parallel to an applied magnetic field and template the alignment of SWNTs sequestered in the micellar cores. The mesophase is a stable single-phase material containing monomers that can be polymerized after nanotube alignment to form the nanocomposite polymer. The space-pervasive nature of magnetic fields and the tunable physicochemical properties of multicomponent mesophases make this an attractive approach that can be leveraged for application in diverse nanocomposite systems.

  6. Time-resolved observation of fast domain-walls driven by vertical spin currents in short tracks

    Energy Technology Data Exchange (ETDEWEB)

    Sampaio, Joao; Lequeux, Steven; Chanthbouala, Andre; Cros, Vincent; Grollier, Julie [Unité Mixte de Physique CNRS/Thales and Université Paris-Sud 11, 1 Ave. A. Fresnel, 91767 Palaiseau (France); Metaxas, Peter J. [Unité Mixte de Physique CNRS/Thales and Université Paris-Sud 11, 1 Ave. A. Fresnel, 91767 Palaiseau (France); School of Physics, M013, University of Western Australia, 35 Stirling Highway, Crawley WA 6009 (Australia); Matsumoto, Rie; Yakushiji, Kay; Kubota, Hitoshi; Fukushima, Akio; Yuasa, Shinji [National Institute of Advanced Industrial Science and Technology (AIST) 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan); Nishimura, Kazumasa; Nagamine, Yoshinori; Maehara, Hiroki; Tsunekawa, Koji [Process Development Center, Canon ANELVA Corporation, Kurigi 2-5-1, Asao, Kawasaki, Kanagawa 215-8550 (Japan)


    We present time-resolved measurements of the displacement of magnetic domain-walls (DWs) driven by vertical spin-polarized currents in track-shaped magnetic tunnel junctions. In these structures, we observe very high DW velocities (600 m/s) at current densities below 10{sup 7} A/cm{sup 2}. We show that the efficient spin-transfer torque combined with a short propagation distance allows avoiding the Walker breakdown process and achieving deterministic, reversible, and fast (≈1 ns) DW-mediated switching of magnetic tunnel junction elements, which is of great interest for the implementation of fast DW-based spintronic devices.

  7. Dielectric properties of vertically aligned multi-walled carbon nanotubes in the terahertz and mid-infrared range (United States)

    Thomson, Mark D.; Zouaghi, Wissem; Meng, Fanqi; Wiecha, Matthias M.; Rabia, Kaneez; Heinlein, Thorsten; Hussein, Laith; Babu, Deepu; Yadav, Sandeep; Engstler, Jörg; Schneider, Jörg J.; Nicoloso, Norbert; Rychetský, Ivan; Kužel, Petr; Roskos, Hartmut G.


    We investigate the broadband dielectric properties of vertically aligned, multi-wall carbon nanotubes (VACNT), over both the terahertz (THz) and mid-infrared spectral ranges. The nominally undoped, metallic VACNT samples are probed at normal incidence, i.e. the response is predominantly due to polarisation perpendicular to the CNT axis. A detailed comparison of various conductivity models and previously reported results is presented for the non-Drude behaviour we observe in the conventional THz range (up to 2.5 THz). Extension to the mid-infrared range reveals an absorption peak at \

  8. Polar-horizontal versus polar-vertical reverse-tilt-domain walls: influence of a pretilt angle below the nematic-isotropic phase transition. (United States)

    Lee, Ji-Hoon; Atherton, Timothy J; Kang, Daeseung; Petschek, Rolfe G; Rosenblatt, Charles


    On cooling through the isotropic-to-nematic phase transition in a cell whose substrates induce a large pretilt angle theta0 from the vertical direction, but with no preferential azimuthal orientation, tilt domains appear. The boundary walls between reverse tilt domains are found to be bendlike and twistlike when theta0(T=TNI) is sufficiently large just below the isotropic-nematic phase transition temperature TNI--i.e., for a nearly planar orientation. Here the director becomes planar approximately midway through the wall, and we refer to this type of wall as "polar horizontal," which is topologically stable. However, if theta0(T=TNI) is sufficiently small just below TNI--i.e., closer to vertical orientation--a splay like and twistlike domain wall obtains, where the director is vertically oriented approximately midway through the wall; we refer to this type of wall as "polar vertical," whose stability depends on the anchoring. On cooling through the nematic phase, the pretilt angle theta0 decreases, with the director aligning closer to the vertical orientation. Nevertheless, the structures of both types of domain walls remain unchanged on variation of theta0 with temperature owing to topological constraints and also are unchanged after the application and removal of a large electric field. We examine the structure of domain walls for the liquid crystal ZLI-4330 (Merck) as a function of pretilt angle theta0(T=TNI) and calculate a critical value theta0c(T=TNI) of the pretilt angle just below TNI for which the predominance of domain walls crosses over from polar horizontal to polar vertical.

  9. Vertical Alignment of Single Wall Carbon Nanotubes (SWNTs) in Thin Polymer Films (United States)

    Mauter, Meagan; Elimelech, Menachem; Osuji, Chinedum


    Thin polymer films (1-10 um) incorporating singly dispersed, vertically aligned carbon nanotubes have a diverse set of potential applications. Desalination membranes that use aligned SWNT as pores, for instance, are predicted to exhibit high flux and salt rejection through size exclusion of hydrated ions. Current fabrication techniques, however, are unable to realize the vertical assembly of narrow diameter SWNTs. Here, we direct the vertical alignment of SWNTs in thin films by using magnetic field aligned lyoptropic surfactant mesophases as structure directing templates. The short alkyl tails of the surfactant impart negative diamagnetic anisotropy to worm-like micelles and lead to parallel alignment of the liquid crystalline (LC) director in an applied magnetic field. The nanotubes orient preferentially with their long axis parallel to the director field of the mesophase, thus promoting their vertical alignment in the system. The LC mesophase incorporates monomers that are polymerized by UV exposure after nanotube alignment to form the polymer matrix. X-ray scattering and optical spectroscopy are used to characterize the field-guided assembly process. The present system may have additional applications for polymer reinforcement using carbon nanotubes.

  10. Stability of viscous film flow coating the interior of a vertical tube with a porous wall (United States)

    Liu, Rong; Ding, Zijing


    The stability of the gravity-driven flow of a viscous film coating the inside of a tube with a porous wall is studied theoretically. We used Darcy's law to describe the motion of fluids in a porous medium. The Beaver-Joseph condition is used to describe the discontinuity of velocity at the porous-fluid interface. We derived an evolution equation for the film thickness using a long-wave approximation. The effect of velocity slip at the porous wall is identified by a parameter β . We examine the effect of β on the temporal stability, the absolute-convective instability (AI-CI), and the nonlinear evolution of the interface deformation. The results of the temporal stability reveal that the effect of velocity slip at the porous wall is destabilizing. The parameter β plays an important role in determining the AI-CI behavior and the nonlinear evolution of the interface. The presence of the porous wall promotes the absolute instability and the formation of the plug in the tube.

  11. Kinematics and dynamics of a solitary wave interacting with varying bathymetry and/or a vertical wall (United States)

    Papoutsellis, Christos; Athanassoulis, Gerassimos; Charalampopoulos, Alexis-Tzianni


    In this work, we investigate the transformations that solitary surface waves undergo during their interaction with uneven seabed and/or fully reflective vertical boundaries. This is accomplished by performing simulations using a non-local Hamiltonian formulation, taking into account full nonlinearity and dispersion, in the presence of variable seabed [1]. This formulation is based on an exact coupled-mode representation of the velocity potential, leading to efficient and accurate computations of the Dirichlet to Neumann operator, required in Zakharov/Craig-Sulem formulation [2], [3]. In addition, it allows for the efficient computation of wave kinematics (velocity, acceleration) and the pressure field, in the time-dependent fluid domain, up to its physical boundaries. Such computations are performed for the case of high-amplitude solitary waves interacting with varying bathymetry and/or a vertical wall, shedding light to their kinematics and dynamics. More specifically, we first consider two benchmark cases, namely the transformation of solitary waves over a plane beach [4], and the reflection of solitary waves on a vertical wall [5]. As a further step, results on the scattering/reflection of a solitary wave due to an undulating seabed, and on the disintegration of a solitary wave travelling form shallow to deep water are also presented. References:[1] G.A. Athanassoulis. & Ch.E. Papoutsellis, in Volume 7: Ocean Engineering, ASME, OMAE2015-41452, p. V007T06A029 (2015)[2] W. Craig, C. Sulem, J. Comp. Phys. 108, 73-83 (1993) [3] V. Zakharov, J. Appl. Mech. Tech. Phys 9, 86-94 (1968)[4] S. Grilli, R. Subramanya, T. Svendsen. & J. Veeramony, J. Waterway, Port, Coastal, Ocean Eng. 120(6), 609-628. (1994)[5] Y.Y. Chen, C. Kharif , J.H. Yang, H.C. Hsu, J. Touboul & J. Chambarel, Eur. J. Mech B-Fluid 49, 20-28 (2015)

  12. Numerical study of three-dimensional natural convection and entropy generation in a cubical cavity with partially active vertical walls

    Directory of Open Access Journals (Sweden)

    Abdullah A.A.A Al-Rashed


    Full Text Available Natural convection and entropy generation due to the heat transfer and fluid friction irreversibilities in a three-dimensional cubical cavity with partially heated and cooled vertical walls has been investigated numerically using the finite volume method. Four different arrangements of partially active vertical sidewalls of the cubical cavity are considered. Numerical calculations are carried out for Rayleigh numbers from (103 ≤ Ra ≤ 106, various locations of the partial heating and cooling vertical sidewalls, while the Prandtl number of air is considered constant as Pr=0.7 and the irreversibility coefficient is taken as (φ=10−4. The results explain that the total entropy generation rate increases when the Rayleigh number increases. While, the Bejan number decreases as the Rayleigh number increases. Also, it is found that the arrangements of heating and cooling regions have a significant effect on the fluid flow and heat transfer characteristics of natural convection and entropy generation in a cubical cavity. The Middle-Middle arrangement produces higher values of average Nusselt numbers.

  13. Phylogenetically distinct cellulose synthase genes support secondary wall thickening in arabidopsis shoot trichomes and cotton fiber. (United States)

    Betancur, Lissete; Singh, Bir; Rapp, Ryan A; Wendel, Jonathan F; Marks, M David; Roberts, Alison W; Haigler, Candace H


    Abstract Through exploring potential analogies between cotton seed trichomes (or cotton fiber) and arabidopsis shoot trichomes we discovered that CesAs from either the primary or secondary wall phylogenetic clades can support secondary wall thickening. CesA genes that typically support primary wall synthesis, AtCesA1,2,3,5, and 6, underpin expansion and secondary wall thickening of arabidopsis shoot trichomes. In contrast, apparent orthologs of CesA genes that support secondary wall synthesis in arabidopsis xylem, AtCesA4,7, and 8, are up-regulated for cotton fiber secondary wall deposition. These conclusions arose from: (a) analyzing the expression of CesA genes in arabidopsis shoot trichomes; (b) observing birefringent secondary walls in arabidopsis shoot trichomes with mutations in AtCesA4, 7, or 8; (c) assaying up-regulated genes during different stages of cotton fiber development; and (d) comparing genes that were co-expressed with primary or secondary wall CesAs in arabidopsis with genes up-regulated in arabidopsis trichomes, arabidopsis secondary xylem, or cotton fiber during primary or secondary wall deposition. Cumulatively, the data show that: (a) the xylem of arabidopsis provides the best model for secondary wall cellulose synthesis in cotton fiber; and (b) CesA genes within a "cell wall toolbox" are used in diverse ways for the construction of particular specialized cell walls.

  14. Tritrichomonas foetus adhere to superhydrophilic vertically aligned multi-walled carbon nanotube surface

    Energy Technology Data Exchange (ETDEWEB)

    Moreira Machado, Susane [Laboratorio de Biologia Celular e Tecidual, Instituto de Pesquisa e Desenvolvimento, Universidade do Vale do Paraiba, Av. Shishima Hifumi 2911, 12244-000, Sao Jose dos Campos, SP (Brazil); Oliveira Lobo, Anderson, E-mail: [Laboratorio de Nanotecnologia Biomedica (NanoBio), Instituto de Pesquisa e Desenvolvimento, Universidade do Vale do Paraiba, Av. Shishima Hifumi 2911, Sao Jose dos Campos, 12244-000, SP (Brazil); Laboratorio de Espectroscopia Vibracional Biomedica, Instituto de Pesquisa e Desenvolvimento, Universidade do Vale do Paraiba, Avenida Shishima Hifumi, 2911, CEP 12244-000, Sao Jose dos Campos, SP (Brazil); Bueno Loureiro Sapucahy, Ariel [Laboratorio de Biologia Celular e Tecidual, Instituto de Pesquisa e Desenvolvimento, Universidade do Vale do Paraiba, Av. Shishima Hifumi 2911, 12244-000, Sao Jose dos Campos, SP (Brazil); Marciano, Fernanda Roberta [Laboratorio de Nanotecnologia Biomedica (NanoBio), Instituto de Pesquisa e Desenvolvimento, Universidade do Vale do Paraiba, Av. Shishima Hifumi 2911, Sao Jose dos Campos, 12244-000, SP (Brazil); Laboratorio de Espectroscopia Vibracional Biomedica, Instituto de Pesquisa e Desenvolvimento, Universidade do Vale do Paraiba, Avenida Shishima Hifumi, 2911, CEP 12244-000, Sao Jose dos Campos, SP (Brazil); Corat, Evaldo Jose [Instituto Nacional de Pesquisas Espaciais (INPE), Laboratorio Associado de Sensores e Materiais (LAS), Av. dos Astronautas 1758, Sao Jose dos Campos, 12227-010 SP (Brazil); Soares da Silva, Newton [Laboratorio de Biologia Celular e Tecidual, Instituto de Pesquisa e Desenvolvimento, Universidade do Vale do Paraiba, Av. Shishima Hifumi 2911, 12244-000, Sao Jose dos Campos, SP (Brazil)


    For the first time, we show that Tritrichomonas foetus can adhere on superhydrophilic vertically aligned carbon nanotubes (VACNT) films. Scanning electron microscopy shows an unusual adhesion with a higher membrane filopodium projection in all directions, directly attached to superhydrophilic VACNT tips. Highlights: {yields} This is a new method to study the T. foetus adhesion mechanism. {yields} SEM images and interfacial adhesion force show a high adhesion level. {yields} It is very important for future understanding mechanism adhesion and protein expression.

  15. Iron melt flow in thin-walled sections using vertically parted moulds

    DEFF Research Database (Denmark)

    Larsen, Per; Tiedje, Niels


    gating systems are used small changes in the casting conditions can change the flow patterns radically. Flow in thin walled sections is not only important in thin walled part. This is illustrated with a brake disc as example. 3 different layouts have been made. The filling sequences have been recorded...... sizes of the dynamic and braking forces in the gating system.......Reducing the fuel consumption of vehicles can be done in many ways. A general way of doing it, is to reduce the weight as it is applicable together with all other means of saving fuel. Even though iron castings have been used in cars from the first car ever build, a big potential still exist...

  16. Convective Flow of a Colloidal Suspension in a Vertical Slot Heated from Side Wall (United States)

    Cherepanov, I. N.; Smorodin, B. L.


    Convective flows and the transport of nanoparticles are numerically investigated in the vertical slot filled with a colloidal suspension and heated from the side. The thermodiffusion and gravitational sedimentation of the nanoparticles are taken into account. Two different regimes of laminar flow are found. The intensity of the first regime is much lower than in molecular liquids (the magnitudes of the convective and diffusion fluxes have the same order). The second regime is more intensive. The transitions between these two regimes are investigated. It is shown that intensive convective flow completely mixes the colloidal suspension to a homogeneous state as a result of the long transient process.

  17. Mortality and life-threatening events after vertical expandable prosthetic titanium rib surgery in children with hypoplastic chest wall deformity. (United States)

    Betz, Randal R; Mulcahey, Mary Jane; Ramirez, Norman; Flynn, John M; Smith, John T; St Hilaire, Tricia; Campbell, Robert M


    Severe complex hypoplastic chest wall and spine deformity with thoracic insufficiency syndrome may be associated with premature death secondary to multisystem involvement. The vertical expandable prosthetic titanium rib (VEPTR) reconstructs the chest wall to address the thoracic insufficiency seen in this patient population. The purpose of this study is to report the mortality and life-threatening adverse events in a cohort of subjects with severe hypoplastic chest wall deformity, specifically with Jeune syndrome and Jarcho-Levin syndrome, after treatment with the VEPTR device. A cohort of 43 patients with either Jeune syndrome or Jarcho-Levin syndrome was extracted from a multicenter Investigational Device Exemption study of 214 patients who had surgery with the VEPTR device. Of the 43 patients, 19 had Jeune syndrome and 24 had Jarcho-Levin syndrome. Fatal and life-threatening adverse events were analyzed, including an assessment of time postsurgery, etiology, and the relationship of the adverse event to the surgical procedure. Four (9%) of the 43 patients died during the follow-up period. All 4 (100%) of these patients had Jeune syndrome. After the initial surgery, 2 died within 6 months, and the remaining 2 within 1 year. Causes of death included respiratory complications in 2, renal failure in 1, and liver failure in 1. An additional 4 (9%) of the 43 patients had life-threatening adverse events. Two (50%) patients were diagnosed with Jeune syndrome and the remaining 2 (50%) with Jarcho-Levin syndrome. Two of the 4 life-threatening events were related to the surgery perioperatively: necrotizing enterocolitis and acute respiratory distress syndrome. The other two events included cardiac arrest secondary to central line placement and Demerol overdose. Surgeons should be aware of the potential for fatality and life-threatening events that occur in patients with hypoplastic chest wall and spine deformity undergoing surgical treatment. The majority of these events

  18. Vertical Alignment of Single-Walled Carbon Nanotubes on Nanostructure Fabricated by Atomic Force Microscope (United States)


    Technology, and Entrepreneurship , NST-4.3, San Diego, CA, August 2008. [10] J. E. Seo, T. J. Lee, K. W. Oh, M. M. Sung, J. W. Lee, W. Yi, H. Lee...T. Chen and J.-I, Chyi, Appl . Phys. Lett. 84, 2919 (2004). [30] J. L. Sauvajol, E. Anglaret, S. Rols and L. Alvarez, Car- bon 40, 1697 (2002). [31...Elastic strain of freely suspended single-wall carbon nanotube ropes. Appl Phys Lett. 1999;74(25):3803-5. [2] Tombler TW, Zhou C, Alexseyev L, Kong

  19. Numerical Study of Natural Convection in a Heated Enclosure with Two Wavy Vertical Walls Using Finite Element Method

    Directory of Open Access Journals (Sweden)

    Pensiri Sompong


    Full Text Available The effects of wavy geometry on natural convection in an enclosure with two wavy vertical walls and filled with fluid saturated porous media are investigated numerically by using finite element method. The wavy enclosure is transformed to a unit square in the computational domain and the finite element formulations are solved in terms of ξη-coordinate based on iterative method. In order to investigate the effects of interested parameters, the values of wave amplitude (λ = 0.05 and 0.1 and number of undulations (n = 1 and 2 are chosen with constants Ra = 105, Da = 10−3, and Pr = 0.71. It is found that the increase in number of undulations has small effect on natural convection inside the enclosure whereas the increase in wave amplitude reduces the strength of convection because higher wave volume plays a barricade role.

  20. Broadband tunable bandpass filters using phase shifted vertical side wall grating in a submicrometer silicon-on-insulator waveguide. (United States)

    Prabhathan, P; Murukeshan, V M; Jing, Zhang; Ramana, Pamidighantam V


    We propose the silicon-on-insulator (SOI) based, phase shifted vertical side wall grating as a resonant transmission filter suitable for dense wavelength division multiplexing (DWDM) communication channels with 100 GHz channel spacing. The gratings are designed and numerically simulated to obtain a minimum loss in the resonant cavity by adjusting the grating parameters so that a high transmittivity can be achieved for the resonant transmission. The resonant grating, which is designed to operate in the DWDM International Telecommunication Union (ITU) grid C band of optical communication, has a high free spectral range of 51.7 nm and a narrow band resonant transmission. The wavelength selectivity of the filter is improved through a coupled cavity configuration by applying two phase shifts to the gratings. The observed channel band width and channel isolation of the resonant transmission filter are good and in agreement with the ITU specifications.

  1. Exact Solutions for Unsteady Free Convection Flow of Casson Fluid over an Oscillating Vertical Plate with Constant Wall Temperature

    Directory of Open Access Journals (Sweden)

    Asma Khalid


    Full Text Available The unsteady free flow of a Casson fluid past an oscillating vertical plate with constant wall temperature has been studied. The Casson fluid model is used to distinguish the non-Newtonian fluid behaviour. The governing partial differential equations corresponding to the momentum and energy equations are transformed into linear ordinary differential equations by using nondimensional variables. Laplace transform method is used to find the exact solutions of these equations. Expressions for shear stress in terms of skin friction and the rate of heat transfer in terms of Nusselt number are also obtained. Numerical results of velocity and temperature profiles with various values of embedded flow parameters are shown graphically and their effects are discussed in detail.

  2. Seismic Dynamic Damage Characteristics of Vertical and Batter Pile-supported Wharf Structure Systems

    Directory of Open Access Journals (Sweden)

    Li Jiren


    Full Text Available Considering a typical steel pipe pile-supported wharf as the research object, finite element analytical models of batter and vertical pile structures were established under the same construction site, service, and geological conditions to investigate the seismic dynamic damage characteristics of vertical and batter pile-supported wharf structures. By the numerical simulation and the nonlinear time history response analysis of structure system and the moment–axial force relation curve, we analyzed the dynamic damage characteristics of the two different structures of batter and vertical piles under different seismic ground motions to provide reasonable basis and reference for designing and selecting a pile-supported wharf structure. Results showed that the axial force of batter piles was dominant in the batter pile structure and that batter piles could effectively bear and share seismic load. Under the seismic ground motion with peak ground acceleration (PGA of 350 Gal and in consideration of the factors of the design requirement of horizontal displacement, the seismic performance of the batter pile structure was better than that of the vertical pile structure. Under the seismic ground motion with a PGA of 1000 Gal, plastic failure occurred in two different structures. The contrastive analysis of the development of plastic damage and the absorption and dissipation for seismic energy indicated that the seismic performance of the vertical pile structure was better than that of the batter pile structure.

  3. Iron Melt Flow in Thin Walled Sections Cast in Vertically Parted Green Sand Moulds

    DEFF Research Database (Denmark)

    Larsen, Per; Andersen, Uffa; Rasmussen, Niels

    and in thin sections have been made via videos of the metal flow. Conventional bottom filling gating systems are shown to give relatively low control over the melt flow. The result is flow patterns being able to change radically from mould to mould due to minor fluctuations in the pouring conditions...... casting thin walled parts, as thin plate shaped ingates are used for casting many parts. This is illustrated with a brake disc. 6 layouts have been made. The filling sequences have been recorded on video. The trials show the difficult task to design a bottom filling system generating no splash during...... of gating systems investigated in this work, cannot be recommended for castings with high demands to the quality, as the variation in the filling patterns can be very large from mould to mould and hence the stability of the quality will be affected....

  4. Prolate spheroidal particles' behavior in a vertical wall-bounded turbulent flow (United States)

    Arcen, B.; Ouchene, R.; Khalij, M.; Tanière, A.


    Direct numerical simulations (DNSs) have been performed to examine the inertia, shape, and gravity field effects on the dynamics of ellipsoidal particles within a vertical turbulent channel flow. To investigate the effects induced by the particle inertia and shape, computations have been conducted for three aspect ratios and two response times. The influence of gravity has been examined through a comparison with DNS data provided in earlier studies without gravity. The originality of this study is that the prediction of the hydrodynamic force and pitching torque acting on the non-spherical particles has been carried out with recent expressions valid outside the Stokes flow regime. With the data extracted from the DNS, a statistical analysis of the particle spatial distribution, orientation, and translational and angular velocities is carried out. Results show that the presence of a significant mean relative velocity between the dispersed and continuous phases greatly modifies the dynamics of non-spherical particles. Without gravity, the dynamics of ellipsoids is close to that of spheres, whereas it becomes strongly dependent on the particle shape with gravity.


    Directory of Open Access Journals (Sweden)

    Ye. M. Frishman


    Full Text Available The system of magnetic support (magnetic suspension – MS using permanent magnets for suspension is under consideration. The permanent magnets are arranged in stepped order. The vertical interaction forces between magnetic systems of the track and the vehicle in dependence on geometrical and physical parameters of the MS are analyzed.

  6. Optimization Design of the Ultra-High-Speed Vertical Rotor’s Supporting Mechanism

    Directory of Open Access Journals (Sweden)

    Yongguang Liu


    Full Text Available How to increase the rotational speed and decrease vibration of the rotor in the acceleration has become an attractive subject, especially for the vertical rotors. This paper introduces a novel supporting mechanism to make the vertical rotor work at 80000 r/min smoothly. How to design and optimize the sensitive parameters of the supporting mechanism is the core problem to reduce the vibration in passing through critical speeds. Therefore, the FEM (finite element method considering the gyroscopic couple is introduced to get the dynamic characteristic of the rotor system. The matching principle of the upper and lower supporting mechanism in the two-degree freedom system is extended to the multiple degree-freedom system, which is applied to optimize the parameters of the supporting mechanism combining with dynamic characteristic of the rotors system. At last, the rotor system can work at 80000 r/min smoothly in experiment.

  7. Conceptual Design of a Floating Support Structure and Mooring System for a Vertical Axis Wind Turbine

    DEFF Research Database (Denmark)

    Berthelsen, Petter Andreas; Fylling, Ivar; Vita, Luca


    This paper deals with the conceptual design of a floating support structure and mooring system for a 5MW vertical axis offshore wind turbine. The work is carried out as part of the DeepWind project, where the main objective is to investigate the feasibility of a floating vertical axis offshore wind...... turbine. The DeepWind concept consists of a Darrieus rotor mounted on a spar buoy support structure. The conceptual design is carried out in an iterative process, involving the different subcomponents. The present work is part of the first design iteration and the objective is to find a feasible floating...... support structure and mooring system for the DeepWind concept. The conceptual design is formulated as an optimization problem: Starting with an initial configuration, the optimization procedure tries to find a cheaper solution while satisfying a set of design requirements. This approach utilizes available...

  8. Water Walls: Highly Reliable and Massively Redundant Life Support Architecture Project (United States)

    National Aeronautics and Space Administration — WATER WALLS (WW) takes an approach to providing a life support system that is biologically and chemically passive, using mechanical systems only for plumbing to...

  9. Constitutive modelling of an arterial wall supported by microscopic measurements

    Directory of Open Access Journals (Sweden)

    Vychytil J.


    Full Text Available An idealized model of an arterial wall is proposed as a two-layer system. Distinct mechanical response of each layer is taken into account considering two types of strain energy functions in the hyperelasticity framework. The outer layer, considered as a fibre-reinforced composite, is modelled using the structural model of Holzapfel. The inner layer, on the other hand, is represented by a two-scale model mimicing smooth muscle tissue. For this model, material parameters such as shape, volume fraction and orientation of smooth muscle cells are determined using the microscopic measurements. The resulting model of an arterial ring is stretched axially and loaded with inner pressure to simulate the mechanical response of a porcine arterial segment during inflation and axial stretching. Good agreement of the model prediction with experimental data is promising for further progress.

  10. Effect of Plane Couette Flow on Natural Convection in a Vertical Slot with Side-Wall Heating (United States)

    Tsunoda, Shuhei; Fujimura, Kaoru


    In a vertical slot with side-wall heating, and depending on the Prandtl number Pr, both steady and oscillatory modes are known to yield a critical condition. Linear stability analysis reveals that a superimposed plane Couette flow yields an instability of the third kind that arises with a Reynolds number in the range - 0.3 ≲ Re ≲ - 0.1 for Pr ≳ 2.15. We focus on this third instability mode. Weakly nonlinear analysis indicates a nonlinear degeneracy occurring on the linear critical curve in the (Re,Gr)-plane where Gr is the Grashof number. Near the upper bound of the Reynolds number range for the existence of the mode, bifurcation on a segment of the critical curve is subcritical. Fully-numerical analysis shows the solution branch extending far from the linearly unstable wavenumber band and exhibiting a complicated bifurcation structure. Near the lower bound, in contrast, bifurcation is supercritical and its characteristics are well explained using weakly nonlinear analyses.

  11. Vertically aligned nanowires on flexible silicone using a supported alumina template prepared by pulsed anodization

    DEFF Research Database (Denmark)

    Mátéfi-Tempfli, Stefan; Mátéfi-Tempfli, M.


    Carpets of vertically aligned nanowires on flexible substrates are successfully realized by a template method. Applying special pulsed anodization conditions, defect-free nanoporous alumina structures supported on polydimethylsiloxane (PDMS), a flexible silicone elastomer, are created. By using...... this template with nanopores ending on a conducting underlayer, a high-density nanowire array can be simply grown by direct DCelectrodeposition on the top of the silicone rubber....

  12. Effect of Vertical Misfit on Screw Joint Stability of Implant-Supported Crowns (United States)

    Assunção, Wirley Gonçalves; Delben, Juliana Aparecida; Tabata, Lucas Fernando; Barão, Valentim Adelino Ricardo; Gomes, Érica Alves


    The passive fit between prosthesis and implant is a relevant factor for screw joint stability and treatment success. The aim of this study was to evaluate the influence of vertical misfit in abutment-implant interface on preload maintenance of retention screw of implant-supported crowns. The crowns were fabricated with different abutments and veneering materials and divided into 5 groups ( n = 12): Gold UCLA abutments cast in gold alloy veneered with ceramic (Group I) and resin (Group II), UCLA abutments cast in titanium veneered with ceramic (Group III) and resin (Group IV), and zirconia abutments with ceramic veneering (Group V). The crowns were attached to implants by gold retention screws with 35-N cm insertion torque. Specimens were submitted to mechanical cycling up to 106 cycles. Measurements of detorque and vertical misfit in abutment-implant interface were performed before and after mechanical cycling. ANOVA revealed statistically significant difference ( P 0.05) between vertical misfit and detorque value. It was concluded that vertical misfit did not influence torque maintenance and the abutments cast in titanium exhibited the highest misfit values.

  13. Trapping of defect point to improve response time via controlled azimuthal anchoring in a vertically aligned liquid crystal cell with polymer wall

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sang Gyun; Kim, Sung Min; Kim, Youn Sik; Lee, Hee Kyu; Lee, Seung Hee [Polymer BIN Fusion Research Center, School of Advanced Materials Engineering, Chonbuk National University, Chonju, Chonbuk 561-756 (Korea, Republic of); Lyu, Jae-Jin; Kim, Kyeong Hyeon [AMLCD Division, Samsung Electronics, Kiheung, Kyunggi-Do 449-711 (Korea, Republic of); Lu, Ruibo; Wu, Shin-Tson [College of Optics and Photonics, University of Central Florida, Orlando FL 32816 (United States)], E-mail:


    Conventional multi-domain vertically aligned liquid crystal (LC) cells have defect points due to the collision of LC directors during the formation of multiple domains. In addition, the location of defects changes with time resulting in a slow response time. This paper proposes a robust vertically aligned LC cell, where the LCs are locked by polymer walls, and the azimuthal anchoring on the surface of the alignment layer is controlled by the polymerization of a UV curable reactive mesogen monomer. As a result, the defect points are trapped at a single position, resulting in a greatly improved response time.

  14. Determination of occlusal vertical dimension by means of controlled pressure against tissues supporting a complete denture. (United States)

    Munakata, Y; Kasai, S


    In order to establish the vertical dimension (VD) of a complete denture prosthesis, a new method of determining a comfortable mandibular position was tested using a recently designed hydraulic jack (hydraulic vertical displacement meter) in five edentulous patients. The device was designed so as to vary occlusal height by means of an extraoral jig connected to intra-oral hydraulic jacks, and to distribute the bite pressure applied against the denture-supporting tissue in approximately the same pattern as that produced by a denture with a VD preferred by the patient. The most comfortable mandibular position determined by this method coincided remarkably with the preferred VD of each patient in our study, indicating that the new device may be used to establish VD for complete denture construction.

  15. Melting and evaporation analysis of the first wall in a water-cooled breeding blanket module under vertical displacement event by using the MARS code

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Geon-Woo [Department of Nuclear Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826 (Korea, Republic of); Cho, Hyoung-Kyu, E-mail: [Department of Nuclear Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826 (Korea, Republic of); Park, Goon-Cherl [Department of Nuclear Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826 (Korea, Republic of); Im, Kihak [National Fusion Research Institute, 169-148 Gwahak-ro, Yuseong-gu, Daejeon 34133 (Korea, Republic of)


    Highlights: • Material phase change of first wall was simulated for vertical displacement event. • An in-house first wall module was developed to simulate melting and evaporation. • Effective heat capacity method and evaporation model were proposed. • MARS code was proposed to predict two-phase phenomena in coolant channel. • Phase change simulation was performed by coupling MARS and in-house module. - Abstract: Plasma facing components of tokamak reactors such as ITER or the Korean fusion demonstration reactor (K-DEMO) can be subjected to damage by plasma instabilities. Plasma disruptions like vertical displacement event (VDE) with high heat flux, can cause melting and vaporization of plasma facing materials and burnout of coolant channels. In this study, to simulate melting and vaporization of the first wall in a water-cooled breeding blanket under VDE, one-dimensional heat equations were solved numerically by using an in-house first wall module, including phase change models, effective heat capacity method, and evaporation model. For thermal-hydraulics, the in-house first wall analysis module was coupled with the nuclear reactor safety analysis code, MARS, to take advantage of its prediction capability for two-phase flow and critical heat flux (CHF) occurrence. The first wall was proposed for simulation according to the conceptual design of the K-DEMO, and the heat flux of plasma disruption with a value of 600 MW/m{sup 2} for 0.1 s was applied. The phase change simulation results were analyzed in terms of the melting and evaporation thicknesses and the occurrence of CHF. The thermal integrity of the blanket first wall is discussed to confirm whether the structural material melts for the given conditions.

  16. CFD coupled kinetic modeling and simulation of hot wall vertical tubular reactor for deposition of SiC crystal from MTS (United States)

    Mollick, P. K.; Venugopalan, R.; Srivastava, D.


    Chemical Vapor Deposition (CVD) process is generally carried out in a hot wall reactor of vertical or horizontal type keeping the substrate inside the chamber on which deposition is targeted. Present study is focused to explain the role of hydrodynamics and temperature conditions on the overall coating rates inside a hot wall vertical tubular reactor. Deposition of β-Silicon Carbide crystals from Methytricholorosilane catalyzed by hydrogen is modeled here considering growth kinetics which can be successfully described - using only two steps. Finite Element Method based simulation is performed to obtain the flow and temperature profiles inside the hot wall reactor. Model equations for kinetics are derived in differential form based on mass balance considering transport of species. Kinetic parameters were approximated comparing the experimentally found coating rates as reported earlier. Present model is seen to fit reasonably well for the wide variation of gas flow rates as well as temperature. Apart from the flow rates of total fluid at inlet and initial wall temperature of reactor, sample position and the inlet diameter of the reactor are found to be key important parameters for the desired coating to take place. Model prediction thus can provide better knowledge in order to carefully choose process parameters in designing the reactor for achieving optimized deposition rates by CVD with desired properties.

  17. Comparison of immediate complete denture, tooth and implant-supported overdenture on vertical dimension and muscle activity

    National Research Council Canada - National Science Library

    Shah, Farhan Khalid; Gebreel, Ashraf; Elshokouki, Ali Hamed; Habib, Ahmed Ali; Porwal, Amit


    To compare the changes in the occlusal vertical dimension, activity of masseter muscles and biting force after insertion of immediate denture constructed with conventional, tooth-supported and Implant...

  18. wall

    Directory of Open Access Journals (Sweden)

    Irshad Kashif


    Full Text Available Maintaining indoor climatic conditions of buildings compatible with the occupant comfort by consuming minimum energy, especially in a tropical climate becomes a challenging problem for researchers. This paper aims to investigate this problem by evaluating the effect of different kind of Photovoltaic Trombe wall system (PV-TW on thermal comfort, energy consumption and CO2 emission. A detailed simulation model of a single room building integrated with PV-TW was modelled using TRNSYS software. Results show that 14-35% PMV index and 26-38% PPD index reduces as system shifted from SPV-TW to DGPV-TW as compared to normal buildings. Thermal comfort indexes (PMV and PPD lie in the recommended range of ASHARE for both DPV-TW and DGPV-TW except for the few months when RH%, solar radiation intensity and ambient temperature were high. Moreover PVTW system significantly reduces energy consumption and CO2 emission of the building and also 2-4.8 °C of temperature differences between indoor and outdoor climate of building was examined.

  19. The effect of frog pressure and downward vertical load on hoof wall weight-bearing and third phalanx displacement in the horse - an in vitro study : research communication

    Directory of Open Access Journals (Sweden)

    A. Olivier


    Full Text Available A shoe was designed to combine the advantages of a reverse shoe and an adjustable heart bar shoe in the treatment of chronic laminitis. This reverse even frog pressure (REFP shoe applies pressure uniformly over a large area of the frog solar surface. Pressure is applied vertically upward parallel to the solar surface of the frog and can be increased or decreased as required. Five clinically healthy horses were humanely euthanased and their dismem-bered forelimbs used in an in vitro study. Frog pressure was measured by strain gauges applied to the ground surface of the carrying tab portion of the shoe. A linear variable distance transducer (LVDT was inserted into a hole drilled in the dorsal hoof wall. The LVDT measured movement of the third phalanx (P3 in a dorsopalmar plane relative to the dorsal hoof wall. The vertical component of hoof wall compression was measured by means of unidirectional strain gauges attached to the toe, quarter and heel of the medial hoof wall of each specimen. The entire limb was mounted vertically in a tensile testing machine and submitted to vertical downward compressive forces of 0 to 2500 Nat a rate of 5 cm/minute. The effects of increasing frog pressure on hoof wall weight-bearing and third phalanx movement within the hoof were determined. Each specimen was tested with the shoe under the following conditions: zero frog pressure; frog pressure used to treat clinical cases of chronic laminitis (7 N-cm; frog pressure clinically painful to the horse as determined prior to euthanasia; frog pressure just alleviating this pain. The specimens were also tested after shoe removal. Total weight-bearing on the hoof wall at zero frog pressure was used as the basis for comparison. Pain-causing and pain-alleviating frog pressures decreased total weight-bearing on the hoof wall (P < 0.05. Frog pressure of 7 N-cm had no statistically significant effect on hoof wall weight-bearing although there was a trend for it to decrease as

  20. Performance of Screen Grid Insulating Concrete Form Walls under Combined In-Plane Vertical and Lateral Loads

    KAUST Repository

    Abdel Mooty, Mohamed


    Insulating Concrete Forms (ICF) walls generally comprise two layers of Expanded Polystyrene (EPS), steel reinforcement is placed in the center between the two layers and concrete is poured to fill the gap between those two layers. ICF\\'s have many advantages over traditional methods of wall construction such as reduced construction time, noise reduction, strength enhancement, energy efficiency, and compatibility with any inside or outside surface finish. The focus of this study is the Screen Grid ICF wall system consisting of a number of beams and columns forming a concrete mesh. The performance of ICF wall systems under lateral loads simulating seismic effect is experimentally evaluated in this paper. This work addresses the effect of the different design parameters on the wall behavior under seismic simulated loads. This includes different steel reinforcement ratio, various reinforcement distribution, wall aspect ratios, different openings sizes for windows and doors, as well as different spacing of the grid elements of the screen grid wall. Ten full scale wall specimens were tested where the effects of the various parameters on wall behavior in terms of lateral load capacity, lateral displacement, and modes of failure are presented. The test results are stored to be used for further analysis and calibration of numerical models developed for this study. © (2011) Trans Tech Publications.

  1. A New Hybrid Method to Correct for Wind Tunnel Wall- and Support Interference On-line

    NARCIS (Netherlands)

    Horsten, B.J.C.; Veldhuis, L.L.M.


    Because support interference corrections are not properly understood, engineers mostly rely on expensive dummy measurements or CFD calculations. This paper presents a method based on uncorrected wind tunnel measurements and fast calculation techniques (it is a hybrid method) to calculate wall

  2. Asc1 supports cell-wall integrity near bud sites by a Pkc1 independent mechanism.

    Directory of Open Access Journals (Sweden)

    Daniel Melamed

    Full Text Available BACKGROUND: The yeast ribosomal protein Asc1 is a WD-protein family member. Its mammalian ortholog, RACK1 was initially discovered as a receptor for activated protein C kinase (PKC that functions to maintain the active conformation of PKC and to support its movement to target sites. In the budding yeast though, a connection between Asc1p and the PKC signaling pathway has never been reported. METHODOLOGY/PRINCIPAL FINDINGS: In the present study we found that asc1-deletion mutant (asc1Delta presents some of the hallmarks of PKC signaling mutants. These include an increased sensitivity to staurosporine, a specific Pkc1p inhibitor, and susceptibility to cell-wall perturbing treatments such as hypotonic- and heat shock conditions and zymolase treatment. Microscopic analysis of asc1Delta cells revealed cell-wall invaginations near bud sites after exposure to hypotonic conditions, and the dynamic of cells' survival after this stress further supports the involvement of Asc1p in maintaining the cell-wall integrity during the mid-to late stages of bud formation. Genetic interactions between asc1 and pkc1 reveal synergistic sensitivities of a double-knock out mutant (asc1Delta/pkc1Delta to cell-wall stress conditions, and high basal level of PKC signaling in asc1Delta. Furthermore, Asc1p has no effect on the cellular distribution or redistribution of Pkc1p at optimal or at cell-wall stress conditions. CONCLUSIONS/SIGNIFICANCE: Taken together, our data support the idea that unlike its mammalian orthologs, Asc1p acts remotely from Pkc1p, to regulate the integrity of the cell-wall. We speculate that its role is exerted through translation regulation of bud-site related mRNAs during cells' growth.

  3. Palladium nanoparticles supported on vertically oriented reduced graphene oxide for methanol electro-oxidation. (United States)

    Yang, Liming; Tang, Yanhong; Luo, Shenglian; Liu, Chengbin; Song, Hejie; Yan, Dafeng


    Reduced graphene oxide (rGO) is a promising support material for nanosized electrocatalysts. However, the conventional stacking arrangement of rGO sheets confines the electrocatalysts between rGO layers, which decreases the number of catalytic sites substantially. We report here a facile synthesis of vertically oriented reduced graphene oxide (VrGO) through cyclic voltammetric electrolysis of graphene oxide (GO) in the presence of Na2 PdCl4 . Experiments without Pd nanoparticles or with a low loading amount of Pd nanoparticles results in the deposition of rGO parallel to the electrodes. The vertical orientation of Pd/rGO nanoflakes causes a remarkable enhancement of the catalytic activity toward methanol electro-oxidation. The mass activity (620.1 A gPd (-1) ) of Pd/VrGO is 1.9 and 6.2 times that of Pd/flat-lying rGO (331.8 A gPd (-1) ) and commercial Pd/C (100.5 A gPd (-1) ), respectively. Furthermore, the Pd/VrGO catalyst shows excellent resistance to CO poisoning. This work provides a simple wet-chemical method for VrGO preparation. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Synthesis of Vertically Aligned Carbon Nanotubes on Silicalite-1 Monolayer-Supported Substrate

    Directory of Open Access Journals (Sweden)

    Wei Zhao


    Full Text Available Monodisperse magnetic Fe3O4 nanoparticles (NPs with the size of ca. 3.5 nm were prepared and used as the catalysts for the synthesis of vertically aligned carbon nanotube (VACNT arrays. A silicalite-1 microcrystal monolayer was used as the support layer between catalyst NPs and the silicon substrate. Compared to our previous report which used radio-frequency- (rf- sputtered Fe2O3 film as the catalyst, Fe3O4 NPs that were synthesized by wet chemical method showed an improved catalytic ability with less agglomeration. The silicalite-1 crystal monolayer acted as an effective “buffer” layer to prevent the catalyst NPs from agglomerating during the reaction process. It is believed that this is the first report that realizes the vertical alignment of CNTs over the zeolite monolayer, namely, silicalite-1 microcrystal monolayer, instead of using the intermediate anodic aluminum oxide (AAO scaffold to regulate the growth direction of CNT products.

  5. Single wall carbon nanotube supports for portable direct methanol fuel cells. (United States)

    Girishkumar, G; Hall, Timothy D; Vinodgopal, K; Kamat, Prashant V


    Single-wall and multiwall carbon nanotubes are employed as carbon supports in direct methanol fuel cells (DMFC). The morphology and electrochemical activity of single-wall and multiwall carbon nanotubes obtained from different sources have been examined to probe the influence of carbon support on the overall performance of DMFC. The improved activity of the Pt-Ru catalyst dispersed on carbon nanotubes toward methanol oxidation is reflected as a shift in the onset potential and a lower charge transfer resistance at the electrode/electrolyte interface. The evaluation of carbon supports in a passive air breathing DMFC indicates that the observed power density depends on the nature and source of carbon nanostructures. The intrinsic property of the nanotubes, dispersion of the electrocatalyst and the electrochemically active surface area collectively influence the performance of the membrane electrode assembly (MEA). As compared to the commercial carbon black support, single wall carbon nanotubes when employed as the support for anchoring the electrocatalyst particles in the anode and cathode sides of MEA exhibited a approximately 30% enhancement in the power density of a single stack DMFC operating at 70 degrees C.

  6. Cross-hole radar scanning of two vertical, permeable, reactive-iron walls at the Massachusetts Military Reservation, Cape Cod, Massachusetts (United States)

    Lane, J.W.; Joesten, P.K.; Savoie, J.G.


    A pilot-scale study was conducted by the U.S. Army National Guard (USANG) at the Massachusetts Military Reservation (MMR) on Cape Cod, Massachusetts, to assess the use of a hydraulic-fracturing method to create vertical, permeable walls of zero-valent iron to passively remediate ground water contaminated with chlorinated solvents. The study was conducted near the source area of the Chemical Spill-10 (CS-10) plume, a plume containing chlorinated solvents that underlies the MMR. Ground-water contamination near the source area extends from about 24 m (meters) to 35 m below land surface. The USANG designed two reactive-iron walls to be 12 m long and positioned 24 to 37 m below land surface to intersect and remediate part of the CS-10 plume.Because iron, as an electrical conductor, absorbs electromagnetic energy, the US Geological Survey used a cross-hole common-depth, radar scanning method to assess the continuity and to estimate the lateral and vertical extent of the two reactive-iron walls. The cross-hole radar surveys were conducted in boreholes on opposite sides of the iron injection zones using electric-dipole antennas with dominant center frequencies of 100 and 250 MHz. Significant decreases in the radar-pulse amplitudes observed in scans that traversed the injection zones were interpreted by comparing field data to results of two-dimensional finite-difference time-domain numerical models and laboratory-scale physical models.The numerical and physical models simulate a wall of perfectly conducting material embedded in saturated sand. Results from the numerical and physical models show that the amplitude of the radar pulse transmitted across the edge of a conductive wall is about 43 percent of the amplitude of a radar pulse transmitted across background material. The amplitude of a radar pulse transmitted through a hole in a conductive wall increases as the aperture of the hole increases. The modeling results indicate that holes with an aperture of less than 40

  7. Green walls in Vancouver

    Energy Technology Data Exchange (ETDEWEB)

    Sharp, R. [Sharp and Diamond Landscape Architecture Inc., Vancouver, BC (Canada)


    With the renewed interest in design for microclimate control and energy conservation, many cities are implementing clean air initiatives and sustainable planning policies to mitigate the effects of urban climate and the urban heat island effect. Green roofs, sky courts and green walls must be thoughtfully designed to withstand severe conditions such as moisture stress, extremes in temperature, tropical storms and strong desiccating winds. This paper focused on the installation of green wall systems. There are 2 general types of green walls systems, namely facade greening and living walls. Green facades are trellis systems where climbing plants can grow vertically without attaching to the surface of the building. Living walls are part of a building envelope system where plants are actually planted and grown in a wall system. A modular G-SKY Green Wall Panel was installed at the Aquaquest Learning Centre at the Vancouver Aquarium in Stanley Park in September 2006. This green wall panel, which was originally developed in Japan, incorporates many innovative features in the building envelope. It provides an exterior wall covered with 8 species of plants native to the Coastal Temperate Rain Forest. The living wall is irrigated by rainwater collected from the roof, stored in an underground cistern and fed through a drip irrigation system. From a habitat perspective, the building imitates an escarpment. Installation, support systems, irrigation, replacement of modules and maintenance are included in the complete wall system. Living walls reduce the surface temperature of buildings by as much as 10 degrees C when covered with vegetation and a growing medium. The project team is anticipating LEED gold certification under the United States-Canada Green Building Council. It was concluded that this technology of vegetated building envelopes is applicable for acoustical control at airports, biofiltration of indoor air, greywater treatment, and urban agriculture and vertical

  8. Feature extraction and wall motion classification of 2D stress echocardiography with support vector machines (United States)

    Chykeyuk, Kiryl; Clifton, David A.; Noble, J. Alison


    Stress echocardiography is a common clinical procedure for diagnosing heart disease. Clinically, diagnosis of the heart wall motion depends mostly on visual assessment, which is highly subjective and operator-dependent. Introduction of automated methods for heart function assessment have the potential to minimise the variance in operator assessment. Automated wall motion analysis consists of two main steps: (i) segmentation of heart wall borders, and (ii) classification of heart function as either "normal" or "abnormal" based on the segmentation. This paper considers automated classification of rest and stress echocardiography. Most previous approaches to the classification of heart function have considered rest or stress data separately, and have only considered using features extracted from the two main frames (corresponding to the end-of-diastole and end-of-systole). One previous attempt [1] has been made to combine information from rest and stress sequences utilising a Hidden Markov Model (HMM), which has proven to be the best performing approach to date. Here, we propose a novel alternative feature selection approach using combined information from rest and stress sequences for motion classification of stress echocardiography, utilising a Support Vector Machines (SVM) classifier. We describe how the proposed SVM-based method overcomes difficulties that occur with HMM classification. Overall accuracy with the new method for global wall motion classification using datasets from 173 patients is 92.47%, and the accuracy of local wall motion classification is 87.20%, showing that the proposed method outperforms the current state-of-the-art HMM-based approach (for which global and local classification accuracy is 82.15% and 78.33%, respectively).

  9. Coil Springs Layer Used to Support a Car Vertical Dynamics Simulator and to Reduce the Maximum Actuation Force

    Directory of Open Access Journals (Sweden)

    Dan N. Dumitriu


    Full Text Available A Danaher Thomson linear actuator with ball screw drive and a realtime control system are used here to induce vertical displacements under the driver/user seat of an in-house dynamic car simulator. In order to better support the car simulator and to dynamically protect the actuator’s ball screw drive, a layer of coil springs is used to support the whole simulator chassis. More precisely, one coil spring is placed vertically under each corner of the rectangular chassis. The paper presents the choice of the appropriate coil springs, so that to minimize as much as possible the ball screw drive task of generating linear motions, corresponding to the vertical displacements and accelerations encountered by a driver during a real ride. For this application, coil springs with lower spring constant are more suited to reduce the forces in the ball screw drive and thus to increase the ball screw drive life expectancy.

  10. Chemical reaction and radiation effects on the transient MHD free convection flow of dissipative fluid past an infinite vertical porous plate with ramped wall temperature

    Directory of Open Access Journals (Sweden)



    Full Text Available A finite-difference analysis is performed to study the effects of thermal radiation and chemical reaction on the transient MHD free convection and mass transform flow of a dissipative fluid past an infinite vertical porous plate subject to ramped wall temperature. The fluid considered here is a gray, absorbing/ /emitting radiation but a non-scattering medium. The dimensionless governing equations are unsteady, coupled and non-linear partial differential equations. An analytical method fails to give a solution. Hence an implicit finite difference scheme of Crank-Nicolson method is employed. The effect of the magnetic parameter (M, chemical reaction parameter (K, radiation parameter (F, buoyancy ratio parameter (N, Schmidt number (Sc on the velocity field and skin friction for both air (Pr = 0.71 and water (Pr = 7 in the presence of both aiding (N>0 and opposing (N<0 flows are extensively discussed with the help of graphs.

  11. An evaluation of chondrocyte morphology and gene expression on superhydrophilic vertically-aligned multi-walled carbon nanotube films

    Energy Technology Data Exchange (ETDEWEB)

    Antonioli, Eliane, E-mail: [Research and Education Institute, Hospital Israelita Albert Einstein, Sao Paulo, SP (Brazil); Lobo, Anderson O., E-mail: [Laboratory of Biomedical Nanotechnology, Universidade do Vale do Paraiba, Sao Jose dos Campos, Sao Paulo (Brazil); Ferretti, Mario, E-mail: [Research and Education Institute, Hospital Israelita Albert Einstein, Sao Paulo, SP (Brazil); Ortophedic Division, Federal University of Sao Paulo, SP (Brazil); Cohen, Moises, E-mail: [Research and Education Institute, Hospital Israelita Albert Einstein, Sao Paulo, SP (Brazil); Ortophedic Division, Federal University of Sao Paulo, SP (Brazil); Marciano, Fernanda R., E-mail: [Laboratory of Biomedical Nanotechnology, Universidade do Vale do Paraiba, Sao Jose dos Campos, Sao Paulo (Brazil); Corat, Evaldo J., E-mail: [Laboratorio Associado de Sensores e Materiais, Instituto Nacional de Pesquisas Espaciais, Sao Jose dos Campos, Sao Paulo (Brazil); Trava-Airoldi, Vladimir J., E-mail: [Laboratorio Associado de Sensores e Materiais, Instituto Nacional de Pesquisas Espaciais, Sao Jose dos Campos, Sao Paulo (Brazil)


    Cartilage serves as a low-friction and wear-resistant articulating surface in diarthrodial joints and is also important during early stages of bone remodeling. Recently, regenerative cartilage research has focused on combinations of cells paired with scaffolds. Superhydrophilic vertically aligned carbon nanotubes (VACNTs) are of particular interest in regenerative medicine. The aim of this study is to evaluate cell expansion of human articular chondrocytes on superhydrophilic VACNTs, as well as their morphology and gene expression. VACNT films were produced using a microwave plasma chamber on Ti substrates and submitted to an O{sub 2} plasma treatment to make them superhydrophilic. Human chondrocytes were cultivated on superhydrophilic VACNTs up to five days. Quantitative RT-PCR was performed to measure type I and type II Collagen, Sox9, and Aggrecan mRNA expression levels. The morphology was analyzed by scanning electron microscopy (SEM) and confocal microscopy. SEM images demonstrated that superhydrophilic VACNTs permit cell growth and adhesion of human chondrocytes. The chondrocytes had an elongated morphology with some prolongations. Chondrocytes cultivated on superhydrophilic VACNTs maintain the level expression of Aggrecan, Sox9, and Collagen II determined by qPCR. This study was the first to indicate that superhydrophilic VACNTs may be used as an efficient scaffold for cartilage or bone repair. Highlights: Black-Right-Pointing-Pointer Chondrocytes were cultivated on Superhydrophilic Vertically Aligned Multiwall Carbon Nanotubes (VACNT). Black-Right-Pointing-Pointer We have shown a correlation between gene expression and thermodynamics aspects. Black-Right-Pointing-Pointer Superhydrhophilic VACNT will be an excellent substrate for cartilage and bone tissue regeneration.

  12. Surface tailored single walled carbon nanotubes as catalyst support for direct methanol fuel cell (United States)

    Kireeti, Kota V. M. K.; Jha, Neetu


    A strategy for tuning the surface property of Single Walled Carbon Nanotubes (SWNTs) for enhanced methanol oxidation reaction (MOR) and oxygen reduction reaction (ORR) along with methanol tolerance is presented. The surface functionality is tailored using controlled acid and base treatment. Acid treatment leads to the attachment of carboxylic carbon (CC) fragments to SWNT making it hydrophilic (P3-SWNT). Base treatment of P3-SWNT with 0.05 M NaOH reduces the CCs and makes it hydrophobic (P33-SWNT). Pt catalyst supported on the P3-SWNT possesses enhanced MOR whereas that supported on P33-SWNT not only enhances ORR kinetics but also possess good tolerance towards methanol oxidation as verified by the electrochemical technique.

  13. Effects of Ramped Wall Temperature on Unsteady Two-Dimensional Flow Past a Vertical Plate with Thermal Radiation and Chemical Reaction

    Directory of Open Access Journals (Sweden)

    V. Rajesh


    Full Text Available The interaction of free convection with thermal radiation of a viscous incompressible unsteady flow past a vertical plate with ramped wall temperature and mass diffusion is presented here, taking into account the homogeneous chemical reaction of first order. The fluid is gray, absorbing-emitting but non-scattering medium and the Rosseland approximation is used to describe the radiative flux in the energy equation. The dimensionless governing equations are solved using an implicit finite-difference method of the Crank-Nicolson type, which is stable and convergent. The velocity profiles are compared with the available theoretical solution and are found to be in good agreement. Numerical results for the velocity, the temperature, the concentration, the local and average skin friction, the Nusselt number and Sherwood number are shown graphically. This work has wide application in chemical and power engineering and also in the study of vertical air flow into the atmosphere. The present results can be applied to an important class of flows in which the driving force for the flow is provided by combination of the thermal and chemical species diffusion effects.

  14. The influence of the tangential velocity of inner rotating wall on axial velocity profile of flow through vertical annular pipe with rotating inner surface

    Directory of Open Access Journals (Sweden)

    Sharf Abdusalam M.


    Full Text Available In the oil and gas industries, understanding the behaviour of a flow through an annulus gap in a vertical position, whose outer wall is stationary whilst the inner wall rotates, is a significantly important issue in drilling wells. The main emphasis is placed on experimental (using an available rig and computational (employing CFD software investigations into the effects of the rotation speed of the inner pipe on the axial velocity profiles. The measured axial velocity profiles, in the cases of low axial flow, show that the axial velocity is influenced by the rotation speed of the inner pipe in the region of almost 33% of the annulus near the inner pipe, and influenced inversely in the rest of the annulus. The position of the maximum axial velocity is shifted from the centre to be nearer the inner pipe, by increasing the rotation speed. However, in the case of higher flow, as the rotation speed increases, the axial velocity is reduced and the position of the maximum axial velocity is skewed towards the centre of the annulus. There is a reduction of the swirl velocity corresponding to the rise of the volumetric flow rate.

  15. The influence of the tangential velocity of inner rotating wall on axial velocity profile of flow through vertical annular pipe with rotating inner surface (United States)

    Sharf, Abdusalam M.; Jawan, Hosen A.; Almabsout, Fthi A.


    In the oil and gas industries, understanding the behaviour of a flow through an annulus gap in a vertical position, whose outer wall is stationary whilst the inner wall rotates, is a significantly important issue in drilling wells. The main emphasis is placed on experimental (using an available rig) and computational (employing CFD software) investigations into the effects of the rotation speed of the inner pipe on the axial velocity profiles. The measured axial velocity profiles, in the cases of low axial flow, show that the axial velocity is influenced by the rotation speed of the inner pipe in the region of almost 33% of the annulus near the inner pipe, and influenced inversely in the rest of the annulus. The position of the maximum axial velocity is shifted from the centre to be nearer the inner pipe, by increasing the rotation speed. However, in the case of higher flow, as the rotation speed increases, the axial velocity is reduced and the position of the maximum axial velocity is skewed towards the centre of the annulus. There is a reduction of the swirl velocity corresponding to the rise of the volumetric flow rate.

  16. Numerical Simulation of Williamson Combined Natural and Forced Convective Fluid Flow between Parallel Vertical Walls with Slip Effects and Radiative Heat Transfer in a Porous Medium

    Directory of Open Access Journals (Sweden)

    Mohammad Yaghoub Abdollahzadeh Jamalabadi


    Full Text Available Numerical study of the slip effects and radiative heat transfer on a steady state fully developed Williamson flow of an incompressible Newtonian fluid; between parallel vertical walls of a microchannel with isothermal walls in a porous medium is performed. The slip effects are considered at both boundary conditions. Radiative highly absorbing medium is modeled by the Rosseland approximation. The non-dimensional governing Navier–Stokes and energy coupled partial differential equations formed a boundary problem are solved numerically using the fourth order Runge–Kutta algorithm by means of a shooting method. Numerical outcomes for the skin friction coefficient, the rate of heat transfer represented by the local Nusselt number were presented even as the velocity and temperature profiles illustrated graphically and analyzed. The effects of the temperature number, Grashof number, thermal radiation parameter, Reynolds number, velocity slip length, Darcy number, and temperature jump, on the flow field and temperature field and their effects on the boundaries are presented and discussed.

  17. Effects of Prophylactic Ankle Supports on Vertical Ground Reaction Force During Landing: A Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Wenxin Niu, Tienan Feng, Lejun Wang, Chenghua Jiang, Ming Zhang


    Full Text Available There has been much debate on how prophylactic ankle supports (PASs may influence the vertical ground reaction force (vGRF during landing. Therefore, the primary aims of this meta-analysis were to systematically review and synthesize the effect of PASs on vGRF, and to understand how PASs affect vGRF peaks (F1, F2 and the time from initial contact to peak loading (T1, T2 during landing. Several key databases, including Scopus, Cochrane, Embase, PubMed, ProQuest, Medline, Ovid, Web of Science, and the Physical Activity Index, were used for identifying relevant studies published in English since inception to April 1, 2015. The computerized literature search and cross-referencing the citation list of the articles yielded 3,993 articles. Criteria for inclusion required that 1 the study was conducted on healthy adults; 2 the subject number and trial number were known; 3 the subjects performed landing with and without PAS; 4 the landing movement was in the sagittal plane; 5 the comparable vGRF parameters were reported; and 6 the F1 and F2 must be normalized to the subject’s body weight. After the removal of duplicates and irrelevant articles, 6, 6, 15 and 11 studies were respectively pooled for outcomes of F1, T1, F2 and T2. This study found a significantly increased F2 (.03 BW, 95% CI: .001, .05 and decreased T1 (-1.24 ms, 95% CI: -1.77, -.71 and T2 (-3.74 ms, 95% CI: -4.83, -2.65 with the use of a PAS. F1 was not significantly influenced by the PAS. Heterogeneity was present in some results, but there was no evidence of publication bias for any outcome. These changes represented deterioration in the buffering characteristics of the joint. An ideal PAS design should limit the excessive joint motion of ankle inversion, while allowing a normal range of motion, especially in the sagittal plane.

  18. Calculation of reaction forces in the boiler supports using the method of equivalent stiffness of membrane wall. (United States)

    Sertić, Josip; Kozak, Dražan; Samardžić, Ivan


    The values of reaction forces in the boiler supports are the basis for the dimensioning of bearing steel structure of steam boiler. In this paper, the application of the method of equivalent stiffness of membrane wall is proposed for the calculation of reaction forces. The method of equalizing displacement, as the method of homogenization of membrane wall stiffness, was applied. On the example of "Milano" boiler, using the finite element method, the calculation of reactions in the supports for the real geometry discretized by the shell finite element was made. The second calculation was performed with the assumption of ideal stiffness of membrane walls and the third using the method of equivalent stiffness of membrane wall. In the third case, the membrane walls are approximated by the equivalent orthotropic plate. The approximation of membrane wall stiffness is achieved using the elasticity matrix of equivalent orthotropic plate at the level of finite element. The obtained results were compared, and the advantages of using the method of equivalent stiffness of membrane wall for the calculation of reactions in the boiler supports were emphasized.

  19. Calculation of Reaction Forces in the Boiler Supports Using the Method of Equivalent Stiffness of Membrane Wall

    Directory of Open Access Journals (Sweden)

    Josip Sertić


    Full Text Available The values of reaction forces in the boiler supports are the basis for the dimensioning of bearing steel structure of steam boiler. In this paper, the application of the method of equivalent stiffness of membrane wall is proposed for the calculation of reaction forces. The method of equalizing displacement, as the method of homogenization of membrane wall stiffness, was applied. On the example of “Milano” boiler, using the finite element method, the calculation of reactions in the supports for the real geometry discretized by the shell finite element was made. The second calculation was performed with the assumption of ideal stiffness of membrane walls and the third using the method of equivalent stiffness of membrane wall. In the third case, the membrane walls are approximated by the equivalent orthotropic plate. The approximation of membrane wall stiffness is achieved using the elasticity matrix of equivalent orthotropic plate at the level of finite element. The obtained results were compared, and the advantages of using the method of equivalent stiffness of membrane wall for the calculation of reactions in the boiler supports were emphasized.

  20. Carbon-Nanotubes-Supported Pd Nanoparticles for Alcohol Oxidations in Fuel Cells: Effect of Number of Nanotube Walls on Activity. (United States)

    Zhang, Jin; Lu, Shanfu; Xiang, Yan; Shen, Pei Kang; Liu, Jian; Jiang, San Ping


    Carbon nanotubes (CNTs) are well known electrocatalyst supports due to their high electrical conductivity, structural stability, and high surface area. Here, we demonstrate that the number of inner tubes or walls of CNTs also have a significant promotion effect on the activity of supported Pd nanoparticles (NPs) for alcohol oxidation reactions of direct alcohol fuel cells (DAFCs). Pd NPs with similar particle size (2.1-2.8 nm) were uniformly assembled on CNTs with different number of walls. The results indicate that Pd NPs supported on triple-walled CNTs (TWNTs) have the highest mass activity and stability for methanol, ethanol, and ethylene glycol oxidation reactions, as compared to Pd NPs supported on single-walled and multi-walled CNTs. Such a specific promotion effect of TWNTs on the electrocatalytic activity of Pd NPs is not related to the contribution of metal impurities in CNTs, oxygen-functional groups of CNTs or surface area of CNTs and Pd NPs. A facile charge transfer mechanism via electron tunneling between the outer wall and inner tubes of CNTs under electrochemical driving force is proposed for the significant promotion effect of TWNTs for the alcohol oxidation reactions in alkaline solutions. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Efficient Growth of Single-Wall Carbon Nanotubes on Supported Fe/Mo Catalyst (United States)

    Hornyak, Louis; Grigorian, Leonid; Dillon, Anne; Parilla, Phillip; Jones, Kim; Heben, Mike


    Efficient chemical vapor deposition (CVD) growth of single-wall carbon nanotubes (SWNT) from methane on supported Fe/Mo catalyst has been demonstrated over a temperature window ranging from 680 to 850 C. Mass gain, transmission electron microscopic (TEM) and Raman data were used to gauge the quality of SWNT growth. Four domains have been characterized. In the low temperature domain, an abrupt rise in SWNT growth occurs as a function of increasing CVD temperature. Next, a plateau region equivalent to the "temperature window" is observed. SWNT growth is favored in this window region. A decline in SWNT production and an increase in non-SWNT hydrocarbons is noted in the 3rd and 4th domains of the profile respectively. The apparent SWNT turn-off is associated with the competitive deposition of amorphous and nanocrystalline carbons.


    Directory of Open Access Journals (Sweden)

    Rashid A. Mangushev


    Full Text Available Bending stiffness and strength of steel sheet retaining walls is strongly dependent on shear resistance of pile interlocks. This fact, usually, is not taken into account in domestic practice of design and construction of sheet walls

  3. Numerical study of mixed convection and conduction in a 2-D square ventilated cavity with an inlet at the vertical glazing wall and outlet at the top surface (United States)

    Arce, J.; Xamán, J.; Álvarez, G.


    A steady state numerical study of combined laminar mixed convection and conduction heat transfer in a ventilated square cavity is presented. The air inlet gap is located at the bottom of a vertical glazing wall and air exits the cavity via a gap located at the top surface. Three locations for the opening at the top surface: left (case a), center (case b) and right side (case c) are considered. All the remaining surfaces are considered adiabatic. The mass, momentum and energy conservation equations were solved using the finite volume method for different Rayleigh numbers in the interval of 104 < Ra < 106 and Reynolds number in the interval of 100 < Re < 700. Temperature, flow field, and heat transfer rates are analyzed. The effect of the interaction between ambient conditions outside the glazing and the air inlet gap at the bottom for different air outlet gap positions at the top surface modifies the flow structure and temperature distribution of the air inside the cavity. The Nusselt number as a function of the Reynolds number was determined for the three cases. It was found that configuration for case (a) removes a higher amount of heat entering the cavity compared to cases (b) and (c). This is due to the short distance between the main stream and the glass wall surface. Thus, the forced airflow entering the cavity is assisted by the buoyancy forces, and most of the cavity remains at the inlet flow temperature, which should be appropriate for warm climates. These results may provide useful information about the heat transfer and fluid flow for future studies.

  4. Effect of axial wall modification on the retention of cement-retained, implant-supported crowns. (United States)

    Tan, Kian M; Masri, Radi; Driscoll, Carl F; Limkangwalmongkol, Penwadee; Romberg, Elaine


    Compromised angulation of implants may result in abutment preparation that is less than ideal. Compromised abutment preparation may affect the retention of implant-retained crowns. The purpose of this study was to investigate the effect of 5 implant abutment designs on the retention of cement-retained crowns by varying the number and position of the axial walls. Five prefabricated abutments were attached to an implant analog and embedded in an acrylic resin block. The first abutment was left intact without modification. Axial walls were partially removed from the remaining abutments to produce abutments with 3 walls, 2 adjacent walls, 2 opposing walls, and 1 wall. Five crowns were made for each group. The screw access channel for the first abutment was completely filled with composite resin and the rest were partially filled. The retentive surface area of each abutment was calculated. Crowns were cemented with zinc phosphate cement. Tensile force was applied to separate the castings from the abutments. Peak load to dislodgment was recorded. A 1-way ANOVA was used to test for a significant difference followed by the Tukey Honestly Significant Difference test (α=.05). The abutment with 2 opposing axial walls had significantly higher retention than that of all other groups (F=149.9, df =24, P<.001). The abutment with 3 walls exhibited the second highest retention and was significantly greater than abutments with 2 adjacent walls, 1, and 4 walls. Abutments with 2 adjacent walls and 1 wall were not significantly different from each other. The unmodified abutment with 4 walls exhibited the lowest retention despite having a large retentive surface area. The retention of cemented crowns on implant abutments is influenced by the number and position of axial walls. Copyright © 2012 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

  5. The treatment of spine and chest wall deformities with fused ribs by expansion thoracostomy and insertion of vertical expandable prosthetic titanium rib: growth of thoracic spine and improvement of lung volumes. (United States)

    Emans, John B; Caubet, Jean François; Ordonez, Claudia L; Lee, Edward Y; Ciarlo, Michelle


    Prospective clinical trial of vertical expandable prosthetic titanium rib (VEPTR) in patients with combined spine and chest wall deformity with scoliosis and fused ribs. Report the efficacy and safety of expansion thoracostomy and VEPTR surgery in the treatment of thoracic insufficiency syndrome (TIS) associated with fused ribs. Traditional attitudes toward early-onset combined chest and spine deformity assume that thoracic deformity is best controlled by treatment directed at spine deformity, often involving early spinal arthrodesis. Campbell and others have heightened awareness of the interrelationship between lung, chest, and spine development during growth and characterized TIS as the inability of the thorax to support normal respiration or lung growth. Expansion thoracostomy and VEPTR insertion was developed to directly control both spine and chest wall deformity during growth, while permitting continued vertebral column and chest growth at an early stage. Multidisciplinary evaluation of children with combined spine and chest wall deformity included pediatric pulmonologist, thoracic, and orthopedic surgeon evaluations. One or more opening wedge expansion thoracostomies and placement of VEPTR devices were performed as described by Campbell, with repeated device lengthenings during growth. Parameters measured included Cobb angle, length of thoracic spine, CT-derived lung volumes, and in older children pulmonary function tests. Thirty-one patients with fused ribs and TIS were treated, 4 of whom had undergone prior spinal arthrodesis at other institutions with continued progression of deformity. In 30 patients, the spinal deformity was controlled and growth continued in the thoracic spine during treatment at rates similar to normals. Increased volume of the constricted hemithorax and total lung volumes obtained during expansion thoracostomy were maintained at follow-up. Complications included device migration, infection, and brachial plexus palsy. Expansion

  6. Mass-produced multi-walled carbon nanotubes as catalyst supports for direct methanol fuel cells. (United States)

    Jang, In Young; Park, Ki Chul; Jung, Yong Chae; Lee, Sun Hyung; Song, Sung Moo; Muramatsu, Hiroyuki; Kim, Yong Jung; Endo, Morinobu


    Commercially mass-produced multi-walled carbon nanotubes, i.e., VGNF (Showa Denko Co.), were applied to support materials for platinum-ruthenium (PtRu) nanoparticles as anode catalysts for direct methanol fuel cells. The original VGNFs are composed of high-crystalline graphitic shells, which hinder the favorable surface deposition of the PtRu nanoparticles that are formed via borohydride reduction. The chemical treatment of VGNFs with potassium hydroxide (KOH), however, enables highly dispersed and dense deposition of PtRu nanoparticles on the VGNF surface. This capability becomes more remarkable depending on the KOH amount. The electrochemical evaluation of the PtRu-deposited VGNF catalysts showed enhanced active surface areas and methanol oxidation, due to the high dispersion and dense deposition of the PtRu nanoparticles. The improvement of the surface deposition states of the PtRu nanoparticles was significantly due to the high surface area and mesorporous surface structure of the KOH-activated VGNFs.

  7. Excellent catalytic effects of multi-walled carbon nanotube supported titania on hydrogen storage of a Mg-Ni alloy. (United States)

    Tan, Yajun; Zhu, Yunfeng; Li, Liquan


    Superior catalytic effects of multi-walled carbon nanotube supported titania synthesized by the sol-gel method on hydrogen storage of a Mg-Ni alloy were investigated. The excellent hydrogen storage properties were obtained: absorbed 5.60 wt% H2 within 60 s at 373 K and released 6.08 wt% H2 within 600 s at 553 K.

  8. Optimum load in various vertical jumps support the maximum dynamic output hypothesis. (United States)

    Suzovic, D; Markovic, G; Pasic, M; Jaric, S


    The aim was to generalize the maximum dynamic output (MDO) hypothesis [i. e., the muscle power output in vertical jumps (VJ) is maximized when loaded with one's own body mass] to variety of VJ. We hypothesized that the subjects' own body (a) would be the optimal load for maximizing the power output (i. e., the no-load condition) and also (b) reveal the maximum benefits of stretch-shortening cycle (SSC). 13 participants performed the maximum squat and various counter-movement jumps when loaded by approximately constant external force ranging from -40% to  + 40% of their body weight (BW). Regarding the first hypothesis, the differences in both the peak and mean power recorded under different load magnitudes revealed maxima close to no-load condition (i. e., from -3% BW to  + 8% BW; R2=0.65-0.96; all Phypothesis, the differences in performance between VJ executed with and without SSC also revealed maxima close to no-load conditions (0-2% BW), while the same differences in the power output were observed under relatively low positive loads (14-25% BW; R² = 0.56-0.95; all Phypothesis. © Georg Thieme Verlag KG Stuttgart · New York.

  9. Wavy-walled bioreactor supports increased cell proliferation and matrix deposition in engineered cartilage constructs. (United States)

    Bueno, Ericka M; Bilgen, Bahar; Barabino, Gilda A


    Hydrodynamic forces in bioreactors can decisively influence extracellular matrix deposition in engineered cartilage constructs. In the present study, the reduced fluid shear, high-axial mixing environment provided by a wavy-walled bioreactor was exploited in the cultivation of cartilage constructs using polyglycolic acid scaffolds seeded with bovine articular chondrocytes. Increased growth as defined by weight, cell proliferation and extracellular matrix deposition was observed in cartilage constructs from wavy-walled bioreactors in comparison with those from spinner flasks cultured under the same conditions. The wet weight composition of 4-week constructs from the wavy-walled bioreactor was similar to that of spinner flask constructs, but the former were 60% heavier due to equally higher incorporation of extracellular matrix and 30% higher cell population. It is most likely that increased construct matrix incorporation was a result of increased mitotic activity of chondrocytes cultured in the environment of the wavy-walled bioreactor. A layer of elongated cells embedded in type I collagen formed at the periphery of wavy-walled bioreactor and spinner flask constructs, possibly as a response to local shear forces. On the basis of the robustness and reproducibility of the extracellular matrix composition of cartilage constructs, the wavy-walled bioreactor demonstrated promise as an experimental cartilage tissue-engineering vessel. Increased construct growth in the wavy-walled bioreactor may lead to enhanced mechanical properties and expedited in vitro cultivation.

  10. Supporting Vertical Transfer: The Role of a Student Union Learning Community (United States)

    Fink, John E.; McShay, James C.; Hernandez, Pamela


    Student affairs practitioners at a large, mid-Atlantic research university created a learning community directed by the student union to support community college transfer students. The authors examined qualitative data and pre/post surveys from 40 learning community participants in the program's pilot year. Results suggested favorable effects of…

  11. An Experimental and Analytical Evaluation of Wall And Window Retrofit Configurations: Supporting the Residential Retrofit Best Practices Guide

    Energy Technology Data Exchange (ETDEWEB)

    Stovall, Therese K [ORNL; Petrie, Thomas [ORNL; Kosny, Jan [ORNL; Childs, Phillip W [ORNL; Atchley, Jerald Allen [ORNL; Hulvey, Kimberly D [ORNL


    A Retrofit Best Practices Guide was developed to encourage homeowners to consider energy conservation issues whenever they modify their siding or windows. In support of this guide, an experimental program was implemented to measure the performance of a number of possible wall siding and window retrofit configurations. Both thermal and air-leakage measurements were made for a 2.4 x 2.4 m (8 x 8 ft) wall section with and without a 0.9 x 1.2 m (3 x 4 ft) window. The windows tested were previously well-characterized at a dedicated window test facility. A computer model was also used to provide information for the Best Practices Guide. The experimental data for walls and windows were used in conjunction with this model to estimate the total annual energy savings for several typical houses in a number of different locations.

  12. Pelvic Organ Support in Animals with Partial Loss of Fibulin-5 in the Vaginal Wall.

    Directory of Open Access Journals (Sweden)

    Kathleen Chin

    Full Text Available Compromise of elastic fiber integrity in connective tissues of the pelvic floor is most likely acquired through aging, childbirth-associated injury, and genetic susceptibility. Mouse models of pelvic organ prolapse demonstrate systemic deficiencies in proteins that affect elastogenesis. Prolapse, however, does not occur until several months after birth and is thereby acquired with age or after parturition. To determine the impact of compromised levels of fibulin-5 (Fbln5 during adulthood on pelvic organ support after parturition and elastase-induced injury, tissue-specific conditional knockout (cKO mice were generated in which doxycycline (dox treatment results in deletion of Fbln5 in cells that utilize the smooth muscle α actin promoter-driven reverse tetracycline transactivator and tetracycline responsive element-Cre recombinase (i.e., Fbln5f/f/SMA++-rtTA/Cre+, cKO. Fbln5 was decreased significantly in the vagina of cKO mice compared with dox-treated wild type or controls (Fbln5f/f/SMA++-rtTA/Cre-/-. In controls, perineal body length (PBL and bulge increased significantly after delivery but declined to baseline values within 6-8 weeks. Although overt prolapse did not occur in cKO animals, these transient increases in PBL postpartum were amplified and, unlike controls, parturition-induced increases in PBL (and bulge did not recover to baseline but remained significantly increased for 12 wks. This lack of recovery from parturition was associated with increased MMP-9 and nondetectable levels of Fbln5 in the postpartum vagina. This predisposition to prolapse was accentuated by injection of elastase into the vaginal wall in which overt prolapse occurred in cKO animals, but rarely in controls. Taken together, our model system in which Fbln5 is conditionally knock-downed in stromal cells of the pelvic floor results in animals that undergo normal elastogenesis during development but lose Fbln5 as adults. The results indicate that vaginal fibulin-5

  13. Detection of heat abduction on the walls by artificial neural network and selection of materials with decision support system

    Directory of Open Access Journals (Sweden)

    Egemen Tekkanat


    Full Text Available Today energy conservation is a very important issue in the world and Turkey. The aim of this study is to minimize the heat abduction, thus to save energy by utilizing the factors to prevent the heat abduction on the walls of buildings. First of all, a back-propagation network model with artificial neural network model was used for the factors that can cause heat loss on the walls. Whether the walls have insulation were considered. After that, Decision Support Systems were used for heat insulation to select the appropriate materials. A Decision Support Model with Analytic Hierarchy Process (AHP was recommended to meet the needs of a customer best and to make better decisions for the selection of the materials. The method was used by construction firms for their decision processes for the best materials and the results were evaluated. After the evaluations were done, the factors that cause heat loss were considered and it became clear which factors were more important for the prevention of heat loss.

  14. Planarian Body-Wall Muscle: Regeneration and Function beyond a Simple Skeletal Support (United States)

    Cebrià, Francesc


    The body-wall musculature of adult planarians consists of intricately organized muscle fibers, which after amputation are regenerated rapidly and with great precision through the proliferation and differentiation of pluripotent stem cells. These traits make the planarian body-wall musculature a potentially useful model for the study of cell proliferation, differentiation, and pattern formation. Planarian body-wall muscle shows some ambiguous features common to both skeletal and smooth muscle cells. However, its skeletal nature is implied by the expression of skeletal myosin heavy-chain genes and the myogenic transcription factor myoD. Where and when planarian stem cells become committed to the myogenic lineage during regeneration, how the new muscle cells are integrated into the pre-existing muscle net, and the identity of the molecular pathway controlling the myogenic gene program are key aspects of planarian muscle regeneration that need to be addressed. Expression of the conserved transcription factor myoD has been recently demonstrated in putative myogenic progenitors. Moreover, recent studies suggest that differentiated muscle cells may provide positional information to planarian stem cells during regeneration. Here, I review the limited available knowledge on planarian muscle regeneration. PMID:26904543

  15. Planarian body-wall muscle: regeneration and function beyond a simple skeletal support

    Directory of Open Access Journals (Sweden)

    Francesc eCebrià


    Full Text Available The body-wall musculature of adult planarians consists of intricately organized muscle fibers, which after amputation are regenerated rapidly and with great precision through the proliferation and differentiation of pluripotent stem cells. These traits make the planarian body-wall musculature a potentially useful model for the study of cell proliferation, differentiation, and pattern formation. Planarian body-wall muscle shows some ambiguous features common to both skeletal and smooth muscle cells. However, its skeletal nature is implied by the expression of skeletal myosin heavy-chain genes and the myogenic transcription factor myoD. Where and when planarian stem cells become committed to the myogenic lineage during regeneration, how the new muscle cells are integrated into the pre-existing muscle net, and the identity of the molecular pathway controlling the myogenic gene program are key aspects of planarian muscle regeneration that need to be addressed. Expression of the conserved transcription factor myoD has been recently demonstrated in putative myogenic progenitors. Moreover, recent studies suggest that differentiated muscle cells may provide positional information to planarian stem cells during regeneration. Here, I review the limited available knowledge on planarian muscle regeneration.

  16. A flavoprotein supports cell wall properties in the necrotrophic fungus Alternaria brassicicola. (United States)

    Pigné, Sandrine; Zykwinska, Agata; Janod, Etienne; Cuenot, Stéphane; Kerkoud, Mohammed; Raulo, Roxane; Bataillé-Simoneau, Nelly; Marchi, Muriel; Kwasiborski, Anthony; N'Guyen, Guillaume; Mabilleau, Guillaume; Simoneau, Philippe; Guillemette, Thomas


    Flavin-dependent monooxygenases are involved in key biological processes as they catalyze a wide variety of chemo-, regio- and enantioselective oxygenation reactions. Flavoprotein monooxygenases are frequently encountered in micro-organisms, most of which require further functional and biocatalytic assessment. Here we investigated the function of the AbMak1 gene, which encodes a group A flavin monooxygenase in the plant pathogenic fungus Alternaria brassicicola, by generating a deficient mutant and examining its phenotype. Functional analysis indicates that the AbMak1 protein is involved in cell wall biogenesis and influences the melanization process. We documented a significant decrease in melanin content in the Δabmak1 strain compared to the wild-type and complemented strains. We investigated the cell wall morphology and physical properties in the wild-type and transformants using electron and atomic force microscopy. These approaches confirmed the aberrant morphology of the conidial wall structure in the Δabmak1 strain which had an impact on hydrophilic adhesion and conidial surface stiffness. However, there was no significant impairment in growth, conidia formation, pathogenicity or susceptibility to various environmental stresses in the Δabmak1 strain. This study sheds new light on the function of a fungal flavin-dependent monooxygenase, which plays an important role in melanization.

  17. Vertically aligned carbon nanotubes/carbon fiber paper composite to support Pt nanoparticles for direct methanol fuel cell application (United States)

    Zhang, Jing; Yi, Xi-bin; Liu, Shuo; Fan, Hui-Li; Ju, Wei; Wang, Qi-Chun; Ma, Jie


    Vertically aligned carbon nanotubes (VACNTs) grown on carbon fiber paper (CFP) by plasma enhanced chemical vapor deposition is introduced as a catalyst support material for direct methanol fuel cells (DMFCs). Well dispersed Pt nanoparticles on VACNTs surface are prepared by impregnation-reduction method. The VACNTs on CFP possess well-maintained alignment, large surface area and good electrical conductivity, which leading to the formation of Pt particles with a smaller size and enhance the Pt utilization rate. The structure and nature of resulting Pt/VACNTs/CFP catalysts for methanol oxidation are investigated by transmission electron microscopy (TEM), X-ray diffraction (XRD) and scanning electron microscope (SEM). With the aid of VACNTs, well-dispersed Pt catalysts enable the reversibly rapid redox kinetic since electron transport efficiently passes through a one-dimensional pathway, which leads to enhance the catalytic activity and Pt utilization rate. Compared with the Pt/XC-72/CFP electrode, the electrochemical measurements results display that the Pt/VACNTs/CFP catalyst shows much higher electrocatalytic activity and better stability for methanol oxidation. In addition, the oxidation current from 200 to 1200 s decayed more slowly for the Pt/VACNTs/CFP than that of the Pt/XC-72/CFP catalysts, indicating less accumulation of adsorbed CO species. All those results imply that the Pt/VACNTs/CFP has a great potential for applications in DMFCs.

  18. Thirsty Walls: A New Paradigm for Air Revitalization in Life Support (United States)

    Graf, John; Brennecke, Joan; Weislogel, Mark


    Carbon Dioxide removal systems on submarines are compact and reliable. They use solubility chemistry. They spray a Carbon Dioxide adsorbing chemical directly into the air stream, and allow the liquid to settle. Carbon Dioxide removal systems on ISS are large and need repair. They use adsorption chemistry. They force air through a bed packed with granular zeolite, and heat the bed to desorb the Carbon Dioxide. The thermal cycles cause the zeolite to dust. New advances in additive manufacturing, and a better understanding of uid behavior in microgravity make it possible to expose a liquid directly to air in a microgravity environment. It is now practical to use submarine style solubility chemistry for atmosphere revitalization in space. It is now possible to develop space systems that achieve submarine levels of reliability. New developments in Ionic Liquid research make it possible to match the solubility performance characteristics of MEA used on submarines - with Ionic Liquids that do not release chemical vapors into the air. "Thirsty Walls" provide gentle, passive contact between ventilation air and Air Revitalization functions of temperature control, relative humidity control, and Carbon Dioxide removal. "Thirsty Walls" eliminates the need of large blowers and compressors that need to force air at high velocities through restrictive Air Revitalization hardware.

  19. Iron (II) tetrakis(diaquaplatinum) octacarboxyphthalocyanine supported on multi-walled carbon nanotubes as effective electrocatalyst for oxygen reduction reaction in alkaline medium

    CSIR Research Space (South Africa)

    Mamuru, SA


    Full Text Available Oxygen reduction reaction (ORR) in alkaline medium at iron (II) tetrakis (diaquaplatinum) octacarboxyphthalocyanine (PtFeOCPc) catalyst supported on multi-walled carbon nanotubes (MWCNTs) has been described. The ORR followed the direct 4-electron...

  20. Studies on the heterogeneous electron transport and oxygen reduction reaction at metal (Co, Fe) octabutylsulphonylphthalocyanines supported on multi-walled carbon nanotube modified graphite electrode

    CSIR Research Space (South Africa)

    Mamuru, SA


    Full Text Available Heterogeneous electron transfer dynamics and oxygen reduction reaction (ORR) activities using octabutylsulphonylphthalocyanine complexes of iron (FeOBSPc) and cobalt (CoOBSPc) supported on multi-walled carbon nanotube (MWCNT) platforms have been...

  1. Vertical microgap and passivity of fit of three-unit implant-supported frameworks fabricated using different techniques. (United States)

    Berejuk, Halina Massignan; Shimizu, Roberto Hideo; de Mattias Sartori, Ivete Aparecida; Valgas, Laiz; Tiossi, Rodrigo


    This study compared the vertical microgaps of milled zirconia and cobalt-chromium (Co-Cr) implant-supported fixed dental prosthesis frameworks to those seen in one-piece frameworks cast with different techniques. Two threaded implants were used to simulate the rehabilitation of a maxillary partially edentulous space from the second premolar to the second molar. Three-unit screw-retained prosthetic frameworks were fabricated and divided into the following groups (n = 10 in each group): 1 = cast in Co-Cr using burnout cylinders; 2 = cast in Co-Cr using cast-on Co-Cr cylinders; 3 = one-piece cast in Co-Cr using a passive fitting technique; 4 = milled Co-Cr framework; 5 = milled zirconia framework. The microgap was measured under an optical microscope at ×25. Readings were made with one screw tightened and with both screws tightened. Data were submitted to statistical analysis to enable comparison between groups (α = .05). All frameworks presented microgaps less than 70 μm under all reading conditions, except for group 1 with the readings made on the side opposite the tightened side (124.22 μm). With one screw tightened, the microgap on the tightened side was significantly smaller in groups 2, 3, and 4. On the opposite side, groups 3, 4, and 5 presented significantly smaller microgaps compared to the other groups. When both screws were tightened, the microgap was significantly smaller in groups 2, 3, and 4. One-piece cast frameworks associated with a passive fitting technique and milled Co-Cr frameworks presented smaller microgaps than the other fabrication methods and materials that were tested.

  2. Electrooxidation of ethanol on novel multi-walled carbon nanotube supported platinum-antimony tin oxide nanoparticle catalysts (United States)

    Guo, Dao-Jun

    We synthesize the new Pt based catalyst for direct ethanol fuel cells using novel multi-walled carbon nanotubes supported platinum-antimony tin oxide (Pt-ATO/MWCNT) nanoparticle as new catalyst support for the first time. The structure of Pt-ATO/MWCNT catalyst is characterized by transmission electron micrograph (TEM) and X-ray diffraction (XRD). The electrocatalytic properties of Pt-ATO/MWCNT catalyst for ethanol electrooxidation reactions are investigated by cyclic voltammetry (CV) and chronoamperometric experiments in acidic medium. The electrocatalytic activity for ethanol electrooxidation reaction shows that high carbon monoxide tolerance and good stability of Pt-ATO/MWCNT catalyst compared with Pt-SnO 2/MWCNT and commercial Pt/C are observed. These results imply that Pt-ATO/MWCNT catalyst has promising potential applications in direct alcohol fuel cells.

  3. Multi-walled carbon nanotube supported CdS-DETA nanocomposite for efficient visible light photocatalysis

    Energy Technology Data Exchange (ETDEWEB)

    Lv, Jiali; Li, Dongpei [College of Physics and Electronic Information, Anhui Key Laboratory of Energetic Materials, Huaibei Normal University, Huaibei, 235000 (China); Dai, Kai, E-mail: [College of Physics and Electronic Information, Anhui Key Laboratory of Energetic Materials, Huaibei Normal University, Huaibei, 235000 (China); Liang, Changhao, E-mail: [College of Physics and Electronic Information, Anhui Key Laboratory of Energetic Materials, Huaibei Normal University, Huaibei, 235000 (China); Key Laboratory of Materials Physics and Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei, 230031 (China); Jiang, Dequan [College of Physics and Electronic Information, Anhui Key Laboratory of Energetic Materials, Huaibei Normal University, Huaibei, 235000 (China); Lu, Luhua [Faculty of Material Science and Chemical Engineering, China University of Geosciences, Wuhan, 430074 (China); Zhu, Guangping [College of Physics and Electronic Information, Anhui Key Laboratory of Energetic Materials, Huaibei Normal University, Huaibei, 235000 (China)


    Designing high performance functional nanomaterials by tuning their dimension at nanoscale and constructing novel interface has been a hot topic in recent years. In this work, multi-walled carbon nanotube (MWCNT)/CdS-diethylenetriamine (DETA) composite photocatalyst was synthesized via hydrothermal method. The structure, morphology, optical property and core level analysis of MWCNT/CdS-DETA nanocomposite were characterized by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectroscopy spectra (EDS), UV–Vis diffuse reflectance spectroscopy (DRS) and X-ray photoelectron spectrum (XPS). CdS-DETA can be uniformly dispersed on the surface of MWCNT. Photocatalytic properties of as-prepared photocatalysts were investigated under 410 nm LED light irradiation for photodegradation of methylene bule (MB). The k{sub app} of MWCNT/CdS-DETA is 0.034 min{sup −1}, which is about 6 times more than pure CdS-DETA. Photostability test indicated that MWCNT/CdS-DETA hybrid can be reused for degradation of organic pollution, suggesting the possible application of MWCNT/CdS-DETA hybrid is the most promising strategy for advanced photocatalyst material design. - Highlights: • Novel MWCNT/CdS-DETA photocatalyst was prepared. • MWCNT/CdS-DETA showed high photocatalytic activity. • MWCNT/CdS-DETA showed long reusable life.

  4. Ultrasonically treated multi-walled carbon nanotubes (MWCNTs) as PtRu catalyst supports for methanol electrooxidation (United States)

    Yang, Chunwei; Hu, Xinguo; Wang, Dianlong; Dai, Changsong; Zhang, Liang; Jin, Haibo; Agathopoulos, Simeon

    In the quest of fabricating supported catalysts, experimental results of transmission electron microscopy, Raman and infrared spectroscopy indicate that ultrasonic treatment effectively functionalizes multi-walled carbon nanotubes (MWCNTs), endowing them with groups that can act as nucleation sites which can favor well-dispersed depositions of PtRu clusters on their surface. Ultrasonic treatment seems to be superior than functionalization via regular refluxing. This is confirmed by the determination of the electrochemistry active surface area (ECA) and the CO-tolerance performance of the PtRu catalysts, measured by adsorbed CO-stripping voltammetry in 0.5 M sulfuric acid solution, and the real surface area of the PtRu catalysts, evaluated by Brunauer-Emmett-Teller (BET) measurements. Finally, the effectiveness for methanol oxidation is assessed by cyclic voltammetry (CV) in a sulfuric acid and methanol electrolyte.

  5. High-performance hydrogen production and oxidation electrodes with hydrogenase supported on metallic single-wall carbon nanotube networks. (United States)

    Svedružić, Draženka; Blackburn, Jeffrey L; Tenent, Robert C; Rocha, John-David R; Vinzant, Todd B; Heben, Michael J; King, Paul W


    We studied the electrocatalytic activity of an [FeFe]-hydrogenase from Clostridium acetobutylicum (CaH2ase) immobilized on single-wall carbon nanotube (SWNT) networks. SWNT networks were prepared on carbon cloth by ultrasonic spraying of suspensions with predetermined ratios of metallic and semiconducting nanotubes. Current densities for both proton reduction and hydrogen oxidation electrocatalytic activities were at least 1 order of magnitude higher when hydrogenase was immobilized onto SWNT networks with high metallic tube (m-SWNT) content in comparison to hydrogenase supported on networks with low metallic tube content or when SWNTs were absent. We conclude that the increase in electrocatalytic activities in the presence of SWNTs was mainly due to the m-SWNT fraction and can be attributed to (i) substantial increases in the active electrode surface area, and (ii) improved electronic coupling between CaH2ase redox-active sites and the electrode surface.

  6. Numerical study on lateral wall displacement of deep excavation supported by IPS earth retention system

    Directory of Open Access Journals (Sweden)

    Tugen Feng


    Full Text Available The objective of this study is to investigate the 3D behavior characteristics of an excavation supported by an innovative prestressed support (IPS earth retention system. A numerical simulation was conducted in order to provide insight into the IPS system behavior by using the FLAC3D package. Prior to the parametric study, validation work was conducted by means of a comparison of the deformation between the field test data and numerical analysis results, and strong agreement was obtained. The reasonable excavation location, layered excavation thickness, and blocked excavation sequence are presented according to variable parameter analysis. In view of the previous findings, certain measurements are proposed in order to control the foundation pit deformation. The results indicate that prestress compensation has a significant effect on the IPS system behavior, while an optimized excavation sequence slightly improves its behavior. With the conclusion proposed based on the numerical results, the aim is to provide reference data for optimization design and the construction sequence.

  7. Morphological study of SiC coating developed on 2D carbon composites using MTS precursor in a hot-wall vertical reactor

    Energy Technology Data Exchange (ETDEWEB)

    Venugopalan, Ramani; Prakash, Jyoti; Dakshinamoorthy, Sathiyamoorthy [Bhabha Atomic Research Centre, Mumbai (India). Powder Metallurgy Div.; Nuwad, Jitendra; Sivan Pillai, Chirakarumpil Gopalan; Tyagi, Avesh Kumar [Bhabha Atomic Research Centre, Mumbai (India). Chemistry Div.


    Silicon carbide coating was developed using chemical vapor deposition on carbon substrate as a protective coating. The present studies were carried out with methyl trichlorosilane as the SiC precursor, at 1673K along with hydrogen and argon as carrier gas using a high-temperature vertical graphite reactor. The SiC coatings were characterized by means of X-ray diffraction for phase identification. Scanning electron microscopy analysis with energy dispersive X-ray spectrometer was also carried out for microstructure and elemental analysis. From the morphological study of different SiC deposits obtained at varying operating parameters it was observed that methyl trichlorosilane feed rate and hydrogen flow rate play a major role in deciding the nature of deposits and the argon percentage in the mixed gas also plays a vital role. (orig.)

  8. Preparation of micelle supported magnetic hydroxylated multi-walled carbon nanotubes based DSPE for determination of PAHs (United States)

    Wang, Mingyu; Zhang, Shaojun; Zhang, Xiao; Li, Deyu


    A micelle supported Fe3O4 magnetic nanoparticles decorated hydroxylated multi-walled carbon nanotubes material was synthesized. The material was facilely synthesized between carbon nanotubes and Fe2+. The synthesized nanomaterial served as an excellent support for micelles, exhibiting high loading capacity and selectivity. The prepared material used in dispersive solid-phase extraction (DSPE) for investigation of gaseous phase polycyclic aromatic hydrocarbons (PAHs) emitted from marine diesel engine for the first time. The application showed good response (R2 > 0.9981) in the range of 0.02 - 1.0 μg/L, satisfactory reproducibility (variation less than ± 10%) and high precision. Limits of detection of sixteen PAHs ranged from 0.009 to 0.018 μg/L (S/N=3). The spiked recovery of proposed method (72.65-96.54 %) was 1.01 - 2.32 times higher than that of the conventional method. The enrichment factors reached to 39.65-121.32 that exhibited good enrichment ability.

  9. Effect of framework material and vertical misfit on stress distribution in implant-supported partial prosthesis under load application: 3-D finite element analysis. (United States)

    Bacchi, Ataís; Consani, Rafael Leonardo Xediek; Mesquita, Marcelo Ferraz; Dos Santos, Mateus Bertolini Fernandes


    This study evaluated the influence of framework material and vertical misfit on stress created in an implant-supported partial prosthesis under load application. The posterior part of a severely reabsorbed jaw with a fixed partial prosthesis above two osseointegrated titanium implants at the place of the second premolar and second molar was modeled using SolidWorks 2010 software. Finite element models were obtained by importing the solid model into an ANSYS Workbench 11 simulation. The models were divided into 15 groups according to their prosthetic framework material (type IV gold alloy, silver-palladium alloy, commercially pure titanium, cobalt-chromium alloy or zirconia) and vertical misfit level (10 µm, 50 µm and 100 µm). After settlement of the prosthesis with the closure of the misfit, simultaneous loads of 110 N vertical and 15 N horizontal were applied on the occlusal and lingual faces of each tooth, respectively. The data was evaluated using Maximum Principal Stress (framework, porcelain veneer and bone tissue) and a von Mises Stress (retention screw) provided by the software. As a result, stiffer frameworks presented higher stress concentrations; however, these frameworks led to lower stresses in the porcelain veneer, the retention screw (faced to 10 µm and 50 µm of the misfit) and the peri-implant bone tissues. The increase in the vertical misfit resulted in stress values increasing in all of the prosthetic structures and peri-implant bone tissues. The framework material and vertical misfit level presented a relevant influence on the stresses for all of the structures evaluated.

  10. Detection of individual iron-oxide nanoparticles with vertical and lateral sensitivity using domain wall nucleation in CoFeB/Pt nanodevices

    Directory of Open Access Journals (Sweden)

    James Wells


    Full Text Available We present new studies of the characteristics and detection ability of nanoscale sensors based on domain wall nucleation within perpendicularly magnetised ultrathin CoFeB/Pt films. A combination of MFM imaging and anomalous Hall effect transport measurements were used to verify and characterise the behaviour of fabricated devices. After initial characterisation, the influence of magnetic nanoparticles on device behaviour was studied using individual iron oxide (FeOx particles mounted on modified atomic force microscopy probes. We demonstrate the successful detection of particles ranging in diameter between 2.8 μm and 100 nm. In the case of the 2.8 μm particle, we have mapped the signal amplitude produced at a variety of distances from the sensor. We find that the particle’s influence may be detected at separations up to 700 nm. Furthermore, we demonstrate a method for resolving the location of a particle with respect to the centre of the device, providing a lateral sensing ability.

  11. Electrocatalytic oxidation of ethylene glycol at palladium-bimetallic nanocatalysts (PdSn and PdNi) supported on sulfonate-functionalised multi-walled carbon nanotubes

    CSIR Research Space (South Africa)

    Ramulifho, T


    Full Text Available Electrocatalytic oxidation of ethylene glycol (EG) in alkaline medium using nano-scaled palladium-based bimetallic catalysts (PdM, where M = Ni and Sn) supported on sulfonated multi-walled carbon nanotubes (SF-MWCNTs) is compared. The bimetallic...

  12. Highly efficient bimetal synergetic catalysis by a multi-wall carbon nanotube supported palladium and nickel catalyst for the hydrogen storage of magnesium hydride. (United States)

    Yuan, Jianguang; Zhu, Yunfeng; Li, Liquan


    A multi-wall carbon nanotube supported Pd and Ni catalyst efficiently catalyzes the hydrogen storage of magnesium hydride prepared by HCS + MM. Excellent hydrogen storage properties were obtained: hydrogen absorption - 6.44 wt% within 100 s at 373 K, hydrogen desorption - 6.41 wt% within 1800 s at 523 K and 6.70 wt% within 400 s at 573 K.

  13. Photocatalysis-assisted water filtration: Using TiO{sub 2}-coated vertically aligned multi-walled carbon nanotube array for removal of Escherichia coli O157:H7

    Energy Technology Data Exchange (ETDEWEB)

    Oza, Goldie; Pandey, Sunil; Gupta, Arvind; Shinde, Sachin; Mewada, Ashmi [N.S. N. Research Centre for Nanotechnology and Bionanotechnology, Jambhul Phata, Kalyan-Badlapur Road, Ambernath (W) 421505, Maharashtra (India); Jagadale, Pravin [DISAT — Department of Applied Science and Technology, Carbon group, Politecnico di Torino (Italy); Sharon, Maheshwar [N.S. N. Research Centre for Nanotechnology and Bionanotechnology, Jambhul Phata, Kalyan-Badlapur Road, Ambernath (W) 421505, Maharashtra (India); Sharon, Madhuri, E-mail: [N.S. N. Research Centre for Nanotechnology and Bionanotechnology, Jambhul Phata, Kalyan-Badlapur Road, Ambernath (W) 421505, Maharashtra (India)


    A porous ceramic was coated with vertically aligned multi-walled carbon nanotubes (MWCNTs) by spray pyrolysis. Titanium dioxide (TiO{sub 2}) nanoparticles were then coated onto this densely aligned MWCNT. The presence of TiO{sub 2}/MWCNT interfacial arrays was confirmed by X-ray diffraction (XRD), scanning electron microscope–energy dispersive analysis of X-ray (SEM–EDAX) and transmission electron microscope (TEM). This is a novel report in which water loaded with a most dreadful enterohemorrhagic pathogenic strain of Escherichia coli O157:H7 was filtered through TiO{sub 2}/MWCNT coated porous ceramic filter and then analysed. Bacterial removal performance was found to be significantly lower in control i.e. plain porous ceramic (P < 0.05) as compared to TiO{sub 2}/MWCNT coated ceramic. The photocatalytic killing rate constant for TiO{sub 2}-ceramic and MWCNT/TiO{sub 2}-ceramic under fluorescent light was found be 1.45 × 10{sup −2} min{sup −1} and 2.23 × 10{sup −2} min{sup −1} respectively. Further, when I–V characteristics were performed for TiO{sub 2}/MWCNT composite, it was corroborated that the current under light irradiation is comparatively higher than that in dark, thus proving it to be photocatalytically efficient system. The enhanced photocatalysis may be a contribution of increased surface area and charge transfer rate as a consequence of aligned MWCNT network. - Highlights: • Coating of vertically aligned MWCNT on ceramic candle filter • Surface orchestration of TiO{sub 2} on MWCNT arrays • I–V characteristic studies are performed under dark and illumination. • Photocatalytic efficiency of TiO{sub 2}/MWCNT arrays is determined using E. coli O157:H7. • Proposed a mechanism of bacterial killing due to free radical formation.

  14. Research data supporting "Magnetic state of multi-layered synthetic antiferromagnets during soliton nucleation and propagation for vertical data transfer"


    Fernández-Pacheco, Amalio; Steinke, Nina-Juliane; Mahendru, Dishant; Welbourne, Alexander; Mansell, Rhodri; Chin, Shin L.; Petit, Dorothée; Lee, Jihyun; Dalgliesh, Robert; Langridge, Sean; Cowburn, Russell P.


    The files comprise the MOKE, MR, PNR data and simulations included in the paper. Additionally, a MATLAB code to calculate AMR-GMR signals from macrospin simulations is included, as well as instructions to run it. This work was supported by the ERC [grant number 247368, 3SPIN], EPSRC [grant number EP/M008517/1] and Winton Foundation [grant number Winton Advanced Research Fellowship].

  15. Reorientation to vertical modulated by combined support surface tilt and virtual visual flow in healthy elders and adults with stroke. (United States)

    Slaboda, Jill C; Keshner, Emily A


    We explored how changes in visual attention impacted postural motor performance in healthy elders and adults post-stroke within a virtual reality environment, including when vestibular information was not perceptible. Visual dependence in 13 healthy (50-80 years) and 13 adults post-stroke (49-70 years) was assessed with a rod-and-frame task. Three degree support surface dorsiflexion tilts at 30°/s were combined with 30° and 45°/s continuous pitch rotations of the visual environment. The support surface remained tilted for 30 s followed by a 0.1°/s return to neutral during continued visual field rotation. Body displacement and ankle muscle responses were recorded, and wavelet transforms calculated. Muscle frequencies and kinematic measures were examined with functional principal component analysis, and weights compared through mixed model repeated measures ANOVA. Both populations exhibited increased backward sway with pitch upward visual field motion; adults post-stroke produced significantly larger muscle responses. Lateral sway was most regulated when visual flow velocity matched platform velocity. Visual flow summed with direction of support surface instability and visually dependent individuals produced more controlled lateral sway when viewing a dynamic visual field. Provoking postural instability within a dynamic visual flow field could serve as a training tool for postural stabilizing actions, particularly when visual dependence is exhibited.

  16. Solar Walls in tsbi3

    DEFF Research Database (Denmark)

    Wittchen, Kim Bjarne

    tsbi3 is a user-friendly and flexible computer program, which provides support to the design team in the analysis of the indoor climate and the energy performance of buildings. The solar wall module gives tsbi3 the capability of simulating solar walls and their interaction with the building....... This version, C, of tsbi3 is capable of simulating five types of solar walls say: mass-walls, Trombe-walls, double Trombe-walls, internally ventilated walls and solar walls for preheating ventilation air. The user's guide gives a description of the capabilities and how to simulate solar walls in tsbi3....

  17. Ni(OH){sub 2} nanoflakes electrodeposited on Ni foam-supported vertically oriented graphene nanosheets for application in asymmetric supercapacitors

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xin; Liu, Jiyue; Wang, Yayu; Zhao, Cuimei; Zheng, Weitao, E-mail:


    Highlights: • Ni(OH){sub 2}/vertically oriented graphene nanosheets (V-GNs) was prepared. • Ni(OH){sub 2}/V-GNs had enhanced specific capacitance, cycling reversibility and stability. • Performance of Ni(OH){sub 2}/GNs/NF-AC asymmetric supercapacitor was studied. - Abstract: Binderless Ni(OH){sub 2} nanoflakes grown on Ni foam (NF)-supported vertically oriented graphene nanosheets (V-GNs) has been fabricated as a positive electrode material for asymmetric supercapacitor (ASC), coupled with activated carbon (AC) as a counter electrode material. The introduction of V-GNs leads to dense growth of nanocrystalline β-Ni(OH){sub 2} that is confirmed by X-ray diffraction, transmission electron microscopic and scanning electron microscopic analyses. The electrochemical performances of the Ni(OH){sub 2}/GNs/NF electrode are characterized by cyclic voltammetry and charge–discharge tests, which exhibit high specific capacitance of 2215 F g{sup −1} at a scan current density of 2.3 A g{sup −1}, enhanced cycling stability and high rate capability. The Ni(OH){sub 2}/GNs/NF-AC-based ASC can achieve a cell voltage of 1.4 V and a specific energy density of 11.11 Wh kg{sup −1} at 0.5 mA cm{sup −2} with a nearly 100% coulombic efficiency at room temperature.

  18. Effects of catalyst support and chemical vapor deposition condition on synthesis of multi-walled carbon nanocoils

    Energy Technology Data Exchange (ETDEWEB)

    Suda, Yoshiyuki, E-mail:; Iida, Tetsuo; Takikawa, Hirofumi; Harigai, Toru [Department of Electrical and Electronic Information Engineering, Toyohashi University of Technology, Toyohashi, Aichi 441-8580 (Japan); Ue, Hitoshi [Fuji Research Laboratory, Tokai Carbon Co., Ltd., Oyama, Shizuoka 410-1431 (Japan); Umeda, Yoshito [Toho Gas Co., Ltd., Tokai, Aichi 476-8501 (Japan)


    Multi-walled carbon nanocoil (MWCNC) is a carbon nanotube (CNT) with helical shape. We have synthesized MWCNCs and MWCNTs hybrid by chemical vapor deposition (CVD). MWCNCs are considered to be a potential material in nanodevices, such as electromagnetic wave absorbers and field emitters. It is very important to take into account the purity of MWCNCs. In this study, we aimed to improve the composition ratio of MWCNCs to MWCNTs by changing catalyst preparation and CVD conditions. As a catalyst, Fe{sub 2}O{sub 3}/zeolite was prepared by dissolving Fe{sub 2}O{sub 3} fine powder and Y-type zeolite (catalyst support material) in ethanol with an Fe density of 0.5wt.% and with a zeolite density of 3.5wt.%. The catalyst-coated Si substrate was transferred immediately onto a hotplate and was heated at 80°C for 5 min. Similarly, Fe{sub 2}O{sub 3}/Al{sub 2}O{sub 3}, Co/zeolite/Al{sub 2}O{sub 3}, Co/zeolite, and Co/Al{sub 2}O{sub 3} were prepared. The effect of the difference of the composite catalysts on synthesis of MWCNCs was considered. The CVD reactor was heated in a tubular furnace to 660-790°C in a nitrogen atmosphere at a flow rate of 1000 ml/min. Subsequently, acetylene was mixed with nitrogen at a flow rate ratio of C{sub 2}H{sub 2}/N{sub 2} = 0.02-0.1. The reaction was kept under these conditions for 10 min. MWCNTs and MWCNCs were well grown by the catalysts of Co/zeolite and Co/Al{sub 2}O{sub 3}. The composition ratio of MWCNCs to MWCNTs was increased by using a combination of zeolite and Al{sub 2}O{sub 3}. The highest composition ratio of MWCNCs to MWCNTs was 12%.

  19. Numerical Simulation of Tire Reinforced Sand behind Retaining Wall Under Earthquake Excitation

    Directory of Open Access Journals (Sweden)

    A. Lazizi


    Full Text Available This paper studies the numerical simulations of retaining walls supporting tire reinforced sand subjected to El Centro earthquake excitation using finite element analysis. For this, four cases are studied: cantilever retaining wall supporting sand under static and dynamical excitation, and cantilever retaining wall supporting waste tire reinforced sand under static and dynamical excitation. Analytical external stability analyses of the selected retaining wall show that, for all four cases, the factors of safety for base sliding and overturning are less than default minimum values. Numerical analyses show that there are no large differences between the case of wall supporting waste tire reinforced sand and the case of wall supporting sand for static loading. Under seismic excitation, the higher value of Von Mises stress for the case of retaining wall supporting waste tire reinforced sand is 3.46 times lower compared to the case of retaining wall supporting sand. The variation of horizontal displacement (U1 and vertical displacement (U2 near the retaining wall, with depth, are also presented.

  20. Safety Aspects for Vertical Wall Breakwaters

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Burcharth, H. F.; Christiani, E.


    and possible level I and D code formats. In the following first the most important failure modes are briefly described, see section 2. It is assumed that the failure modes can be modelled by limit state functions. Wave load models are described in section 3. In section 5 uncertainties related to the parameters...

  1. Computer aided process planning for high-speed milling of thin-walled parts : strategy-based support

    NARCIS (Netherlands)

    Popma, M.G.R.


    Technological developments have made high-speed milling economically attractive. It is now a manufacturing technology that can competitively manufacture thin-walled parts. Such parts however can require a lot of material to be machined. With high-speed milling, this can take a lot of toolpaths.

  2. Wall Vegetation Characteristics of Urban and Sub-Urban Areas

    Directory of Open Access Journals (Sweden)

    Emrah Yalcinalp


    Full Text Available Unfortunately, we live in a greedy little world and horizontal areas are often too expensive to leave to nature on them. Therefore, creating gardens on vertical surfaces of urban areas has recently been very important to supporting sustainability because these surfaces are still found to be commercially useless compared with green areas which are generally under pressure from commercial demands and politics. However, these artificial vertical green surfaces are still too far from being common, while too many ordinary walls are spontaneously covered with vegetation already. In this study, we try to address the dynamics of wall vegetation as it has a great potential to make the cities more sustainable. Totally 70 walls (35 in urban and 35 in sub-urban areas in Trabzon city were examined regarding their ecological, physical and vegetation characteristics. Having identified 1540 plant samples collected from the walls during a year-round intensive field study, we performed statistical analyzes to enumerate the wall vegetation depending on the ecological characteristics; to evaluate if there are different wall vegetation compositions in urban and sub-urban areas; and finally to evaluate growth conditions and basic challenges for the wall vegetation.

  3. Deflections of an implant-supported cantilever beam subjected to vertically directed loads: in vitro measurements in three dimensions using an optoelectronic method. I. Experimental set-up. (United States)

    Cassel, Björn; Lundgren, Dan; Karlsson, Dan


    The aim of this in vitro study was to develop and test an experimental set-up consisting of a video camera and computer-based optoelectronic motion analysis system, synchronized with a loading device, for studying load-dependent deflections in three dimensions of single implant-supported cantilever beams. One Brånemark System implant was tightly screwed into a steel plate so that the entire implant became submerged. An abutment was attached to the implant and a cast 22-mm-long cantilever gold alloy beam incorporating a prefabricated gold cylinder was attached to the abutment with a prosthetic gold screw. A force transducer was glued on the upper surface of the beam end with its centre 19.4 mm from the centre of the implant abutment gold cylinder unit to register the applied load. A specially designed loading device was used to apply increasing vertical loads of the beam end via the transducer. The motion analysis system was synchronized with the transducer to enable measurements of three-dimensional positional changes of the beam end related to known loads. Vertical loads from 15.7 to 40.4 N were applied resulting in vertical positional changes of the beam end ranging from 40.8 to 225.2 μm (z-axis). The corresponding horizontal changes perpendicular to the long axis of the beam (y-axis) due to counterclockwise horizontal rotation of the beam around the abutment- and prosthetic cylinder threads varied from 7.4 to 77.4 μm. This rotation changed the position of the beam end from 11.9 to 49.3 μm along the x-axis of the coordinate system toward the supporting implant. It was possible to arrange an experimental set-up for optoelectronic 3-D measurements within such a limited measurement volume that would permit satisfactory registrations of small load-dependent deflections of the prosthetic beam and implant components. © 2010 John Wiley & Sons A/S.

  4. A low-potential, H{sub 2}O{sub 2}-assisted electrodeposition of cobalt oxide/hydroxide nanostructures onto vertically-aligned multi-walled carbon nanotube arrays for glucose sensing

    Energy Technology Data Exchange (ETDEWEB)

    Yang Jiang [Food and Bioprocess Engineering laboratory, Department of Biological Systems Engineering, University of Wisconsin-Madison, 460 Henry Mall, Madison, WI 53706 (United States); Zhang Weide [Nanoscience Research Center, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510630 (China); Gunasekaran, Sundaram, E-mail: [Food and Bioprocess Engineering laboratory, Department of Biological Systems Engineering, University of Wisconsin-Madison, 460 Henry Mall, Madison, WI 53706 (United States)


    Highlights: > We successfully synthesized CoOx.nH{sub 2}O-MWCNTs nanocomposites using a cathodic electrochemical reduction of H{sub 2}O{sub 2} to deposit cobalt oxide/hydroxide nanostructures onto vertically well-aligned MWCNTs arrays. > This is an enzyme-free sensor. > Under optimal detection conditions, the sensor showed a good-enough sensitivity of 162.8 {mu}A mM{sup -1} cm{sup -2}, a low detection limit of 2.0 {mu}M (S/N = 3) and a fast response of less than 4 s within the linear range of up to 4.5 mM. > Other advantages of the sensor for Glc measurements include high insensitivity to common interferences, long-term stability, reproducibility and resistance to chloride poisoning without additional outer membrance like Nafion. Therefor it is useful for routine Glc analysis. > The novel nanocomposite material with good mechanical strength and high conductivity can be planted into microchannels to conduct sophisticated lab-on-a-chip Glc detection. - Abstract: A novel nanocomposite was synthesized using a cathodic, low-potential, electrochemical reduction of H{sub 2}O{sub 2} to homogeneously deposit cobalt oxide/hydroxide (denoted as CoOx.nH{sub 2}O) nanostructures onto vertically well-aligned multi-walled carbon nanotube arrays (MWCNTs), while the MWCNTs were prepared by catalytic chemical vapor deposition (CVD) on a tantalum (Ta) substrate. The CoOx.nH{sub 2}O-MWCNTs nanocomposite exhibits much higher electrocatalytic activity towards glucose (Glc) after modification with CoOx.nH{sub 2}O than before. This non-enzymatic Glc sensor has a high sensitivity (162.8 {mu}A mM{sup -1} cm{sup -2}), fast response time (<4 s) and low detection limit (2.0 {mu}M at signal/noise ratio = 3), and a linear dynamic range up to 4.5 mM. The sensor output is stable over 30 days and unaffected by common interferents that co-exist with Glc in analytical samples; it is also resistant to chloride poisoning. These features make the CoOx.nH{sub 2}O-MWCNTs nanocomposite a promising electrode

  5. Increasing plantarflexion angle during landing reduces vertical ground reaction forces, loading rates and the hip's contribution to support moment within participants. (United States)

    Rowley, K Michael; Richards, James G


    The ankle joint's role in shock absorption during landing has been researched in many studies, which have found that landing with higher amounts of plantarflexion (PF) results in lower peak vertical ground reaction forces and loading rates. However, there has not yet been a study that compares drop landings within participants along a quantitative continuum of PF angles. Using a custom-written real-time feedback program, participants adjusted their ankles to an instructed PF angle and dropped onto two force platforms. For increasing PF, peak ground reaction force and peak loading rate during weight acceptance decreased significantly. The hip's contribution to peak support moment decreased as PF at initial contact increased up to 30°. The ankle and knee contributions increased over this same continuum of PF angles. There appears to be no optimal PF angle based on peak ground reaction force and loading rate measurements, but there may be an optimum where joint contributions to peak support moment converge and the hip moment's contribution is minimised.

  6. A Combined Experimental/Analytical Approach to Support the Design of a Lightweight, Rigid-Wall, Mobile Shelter (United States)


    Millisecond Time Scale 37 20 S 1,5 E 0 Center of Front-End Wall -- 889 * . 1273 ! 0 5 3252 0 3255 00-3258 9 -, - 4129 Cete ofDo-n al5370 1.0 -10568 00 0 1 02 03...Output of Sandwich Elements jlN Nodol L"O W9Cntro Ra 4KVW t27 Cete d ur oa 65 Carter of DoE SdWWlI Figure9 F5Ndlor lcatofo Time-Hiory rutput 40 p-= + U

  7. Electrocatalytic properties of platinum nanoparticles supported on fluorine tin dioxide/multi-walled carbon nanotube composites for methanol electrooxidation in acidic medium. (United States)

    Guo, Dao-Jun; Jing, Zhi-Hong


    Fluorine tin oxide (FTO) and multi-walled carbon nanotube (MWCNT) composites synthesized by a sol-gel process followed by a hydrothermal treatment process have been explored as a support for Pt nanoparticles (Pt-FTO/MWCNTs). X-ray diffraction analysis and high resolution transmission electron microscopy show that the Pt and FTO nanoparticles with crystallite size of around 4-8 nm are highly dispersed on the surface of MWCNTs. Pt-FTO/MWCNT catalyst is evaluated in terms of the electrochemical catalytic activity for methanol electrooxidation using cyclic voltammetry, steady state polarization experiments, and electrochemical impedance spectroscopy technique in acidic medium. The Pt-FTO/MWCNT catalyst exhibits a higher intrinsic catalytic activity for methanol electrooxidation with high stability during potential cycling than Pt nanoparticles supported on tin dioxide/multi-walled carbon nanotube composites. The results suggest that FTO/MWCNT composites could be considered as an alternative support for Pt-based electrocatalysts in direct alcohol fuel cells. Copyright © 2011 Elsevier Inc. All rights reserved.

  8. Phylogeny of nodulation and nitrogen-fixation genes in Bradyrhizobium: supporting evidence for the theory of monophyletic origin, and spread and maintenance by both horizontal and vertical transfer. (United States)

    Menna, Pâmela; Hungria, Mariangela


    /housekeeping genes, in addition to shorter nodY/K sequences and the absence of nodZ, highlights a co-evolution process. Additionally, in a group of B. japonicum strains that were symbionts of soybean, vertical transfer seemed to represent the main genetic event. In conclusion, clustering of nodA and nifH gives additional support to the theory of monophyletic origin of the symbiotic genes in Bradyrhizobium and, in addition to the analysis of nodY/K and nodZ, indicates spread and maintenance of nod and nif genes through both vertical and horizontal transmission, apparently with the dominance of one or other of these events in some groups of strains.

  9. Effects of aortic root motion on wall stress in the Marfan aorta before and after personalised aortic root support (PEARS) surgery. (United States)

    Singh, S D; Xu, X Y; Pepper, J R; Izgi, C; Treasure, T; Mohiaddin, R H


    Aortic root motion was previously identified as a risk factor for aortic dissection due to increased longitudinal stresses in the ascending aorta. The aim of this study was to investigate the effects of aortic root motion on wall stress and strain in the ascending aorta and evaluate changes before and after implantation of personalised external aortic root support (PEARS). Finite element (FE) models of the aortic root and thoracic aorta were developed using patient-specific geometries reconstructed from pre- and post-PEARS cardiovascular magnetic resonance (CMR) images in three Marfan patients. The wall and PEARS materials were assumed to be isotropic, incompressible and linearly elastic. A static load on the inner wall corresponding to the patients' pulse pressure was applied. Cardiovascular MR cine images were used to quantify aortic root motion, which was imposed at the aortic root boundary of the FE model, with zero-displacement constraints at the distal ends of the aortic branches and descending aorta. Measurements of the systolic downward motion of the aortic root revealed a significant reduction in the axial displacement in all three patients post-PEARS compared with its pre-PEARS counterparts. Higher longitudinal stresses were observed in the ascending aorta when compared with models without the root motion. Implantation of PEARS reduced the longitudinal stresses in the ascending aorta by up to 52%. In contrast, the circumferential stresses at the interface between the supported and unsupported aorta were increase by up to 82%. However, all peak stresses were less than half the known yield stress for the dilated thoracic aorta. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Transparent and Self-Supporting Graphene Films with Wrinkled- Graphene-Wall-Assembled Opening Polyhedron Building Blocks for High Performance Flexible/Transparent Supercapacitors. (United States)

    Li, Na; Huang, Xuankai; Zhang, Haiyan; Li, Yunyong; Wang, Chengxin


    Improving mass loading while maintaining high transparency and large surface area in one self-supporting graphene film is still a challenge. Unfortunately, all of these factors are absolutely essential for enhancing the energy storage performance of transparent supercapacitors for practical applications. To solve the above bottleneck problem, we produce a novel self-supporting flexible and transparent graphene film (STF-GF) with wrinkled-wall-assembled opened-hollow polyhedron building units. Taking advantage of the microscopic morphology, the STF-GF exhibits improved mass loading with high transmittance (70.2% at 550 nm), a large surface area (1105.6 m2/g), and good electrochemical performance: high energy (552.3 μWh/cm3), power densities (561.9 mW/cm3), a superlong cycle life, and good cycling stability (the capacitance retention is ∼94.8% after 20,000 cycles).

  11. Development of a self-supported single-wall carbon nanotube-based gas diffusion electrode with spatially well-defined reaction and diffusion layers (United States)

    Drillet, J.-F.; Bueb, H.; Dettlaff-Weglikowska, U.; Dittmeyer, R.; Roth, S.

    This work reports on the development of a solvent-free method for the fabrication of a self-supported single-wall carbon nanotubes electrode, which is based on successive sedimentation of both SWCNT/surfactant and PtRu-SWCNT/surfactant suspensions followed by a thermal treatment at 130 °C. The as-prepared self-supported electrode showed sufficient mechanical strength for half-cell investigation and membrane-electrodes assembly fabrication. By using a Pt catalyst loading of 1 mg cm -2, the overall thickness of the gas diffusion electrode reached 95 μm. Its electrochemical activity towards methanol oxidation was investigated by means of cyclic voltammetry and current-voltage polarisation measurements under half-cell and direct methanol fuel cell conditions.

  12. Development of a self-supported single-wall carbon nanotube-based gas diffusion electrode with spatially well-defined reaction and diffusion layers

    Energy Technology Data Exchange (ETDEWEB)

    Drillet, J.-F.; Bueb, H.; Dittmeyer, R. [DECHEMA e.V., Society for Chemical Engineering and Biotechnology, Karl Winnacker Institute, Theodor-Heuss-Allee 25, 60486 Frankfurt am Main (Germany); Dettlaff-Weglikowska, U.; Roth, S. [Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569 Stuttgart (Germany)


    This work reports on the development of a solvent-free method for the fabrication of a self-supported single-wall carbon nanotubes electrode, which is based on successive sedimentation of both SWCNT/surfactant and PtRu-SWCNT/surfactant suspensions followed by a thermal treatment at 130 C. The as-prepared self-supported electrode showed sufficient mechanical strength for half-cell investigation and membrane-electrodes assembly fabrication. By using a Pt catalyst loading of 1 mg cm{sup -2}, the overall thickness of the gas diffusion electrode reached 95 {mu}m. Its electrochemical activity towards methanol oxidation was investigated by means of cyclic voltammetry and current-voltage polarisation measurements under half-cell and direct methanol fuel cell conditions. (author)

  13. Development of Pd and Pd-Co catalysts supported on multi-walled carbon nanotubes for formic acid oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Morales-Acosta, D.; Godinez, Luis A.; Rodriguez, H.G.; Arriaga, L.G. [Centro de Investigacion y Desarrollo Tecnologico en Electroquimica, Parque Tecnologico Queretaro, Sanfandila, Pedro Escobedo, C.P. 76703 Queretaro (Mexico); Ledesma-Garcia, J. [Division de Investigacion y Posgrado, Facultad de Ingenieria, Universidad Autonoma de Queretaro, Cerro de las Campanas S/N, C.P. 76010, Queretaro, Qro. (Mexico); Alvarez-Contreras, L. [Centro de Investigacion en Materiales Avanzados S. C., Complejo Industrial Chihuahua, C.P. 31109, Chihuahua, Chih. (Mexico)


    Pd-Co and Pd catalysts were prepared by the impregnation synthesis method at low temperature on multi-walled carbon nanotubes (MWCNTs). The nanotubes were synthesized by spray pyrolysis technique. Both catalysts were obtained with high homogeneous distribution and particle size around 4 nm. The morphology, composition and electrocatalytic properties were investigated by transmission electron microscopy, scanning electron microscopy-energy dispersive X-ray analysis, X-ray diffraction and electrochemical measurements, respectively. The electrocatalytic activity of Pd and PdCo/MWCNTs catalysts was investigated in terms of formic acid electrooxidation at low concentration in H{sub 2}SO{sub 4} aqueous solution. The results obtained from voltamperometric studies showed that the current density achieved with the PdCo/MWCNTs catalyst is 3 times higher than that reached with the Pd/MWCNTs catalyst. The onset potential for formic acid electrooxidation on PdCo/MWCNTs electrocatalyst showed a negative shift ca. 50 mV compared with Pd/MWCNTs. (author)

  14. Vertical marginal gap evaluation of conventional cast and computer numeric controlled-milled titanium full-arch implant-supported frameworks. (United States)

    Alfadda, Sara A


    To use a novel approach to measure the amount of vertical marginal gap in computer numeric controlled (CNC)-milled titanium frameworks and conventional cast frameworks. Ten cast frameworks were fabricated on the mandibular master casts of 10 patients. Then, 10 CNC-milled titanium frameworks were fabricated by laser scanning the cast frameworks. The vertical marginal gap was measured and analyzed using the Contura-G2 coordinate measuring machine and special computer software. The CNC-milled titanium frameworks showed an overall reduced mean vertical gap compared with the cast frameworks in all five analogs. This difference was highly statistically significant in the distal analogs. The largest mean gap in the cast framework was recorded in the most distal analogs, and the least amount was in the middle analog. Neither of the two types of frameworks provided a completely gap-free superstructure. The CNCmilled titanium frameworks showed a significantly smaller vertical marginal gap than the cast frameworks.

  15. Details of left ventricular radial wall motion supporting the ventricular theory of the third heart sound obtained by cardiac MR. (United States)

    Codreanu, I; Robson, M D; Rider, O J; Pegg, T J; Dasanu, C A; Jung, B A; Rotaru, N; Clarke, K; Holloway, C J


    Obtaining new details of radial motion of left ventricular (LV) segments using velocity-encoding cardiac MRI. Cardiac MR examinations were performed on 14 healthy volunteers aged between 19 and 26 years. Cine images for navigator-gated phase contrast velocity mapping were acquired using a black blood segmented κ-space spoiled gradient echo sequence with a temporal resolution of 13.8 ms. Peak systolic and diastolic radial velocities as well as radial velocity curves were obtained for 16 ventricular segments. Significant differences among peak radial velocities of basal and mid-ventricular segments have been recorded. Particular patterns of segmental radial velocity curves were also noted. An additional wave of outward radial movement during the phase of rapid ventricular filling, corresponding to the expected timing of the third heart sound, appeared of particular interest. The technique has allowed visualization of new details of LV radial wall motion. In particular, higher peak systolic radial velocities of anterior and inferior segments are suggestive of a relatively higher dynamics of anteroposterior vs lateral radial motion in systole. Specific patterns of radial motion of other LV segments may provide additional insights into LV mechanics. The outward radial movement of LV segments impacted by the blood flow during rapid ventricular filling provides a potential substrate for the third heart sound. A biphasic radial expansion of the basal anteroseptal segment in early diastole is likely to be related to the simultaneous longitudinal LV displacement by the stretched great vessels following repolarization and their close apposition to this segment.

  16. Reinforcement mechanism of multi-anchor wall with double wall facing (United States)

    Suzuki, Kouta; Kobayashi, Makoto; Miura, Kinya; Konami, Takeharu; Hayashi, Taketo


    The reinforced soil wall has high seismic performance as generally known. However, the seismic behavior has not been clarified accurately yet, especially on multi-anchor wall with double wall facing. Indefinite behavior of reinforced soil wall during earthquake make us complicated in case with adopting to the abutment, because of arrangement of anchor plate as reinforcement often different according to the width of roads. In this study, a series of centrifuge model tests were carried out to investigate the reinforcement mechanism of multi anchor wall with double wall facing from the perspective of the vertical earth pressure. Several types of reinforce arrangement and rigid wall were applied in order to verify the arch function in the reinforced regions. The test results show unique behavior of vertical earth pressure, which was affected by arch action. All the vertical earth pressure placed behind facing panel, are larger than that of middle part between facing panel despite of friction between backfill and facing panel. Similar results were obtained in case using rigid wall. On the other hands, the vertical earth pressure, which were measured at the 3cm high from bottom of model container, shows larger than that of bottom. This results show the existence of arch action between double walls. In addition, it implies that the wall facing of such soil structure confined the backfill as pseudo wall, which is very reason that the multi anchor wall with double wall facing has high seismic performance.

  17. Influence of a boatlanding and j-tubes on wave loads and wall thickness of the monopile support structure design

    NARCIS (Netherlands)

    Segeren, M.L.A.


    Support structures for offshore wind turbines play a significant part in the cost of offshore wind energy. With current access systems a conventional boat landing is not necessary. Secondary steel, such as a boat landing and J-tube, influences wave loads. A way of taking the secondary steel items

  18. CosmoQuest: Supporting Subject Matter Experts in Broadening the Impacts of their Work beyond their Institutional Walls. (United States)

    Noel-Storr, J.; Buxner, S.; Grier, J.; Gay, P.


    CosmoQuest is a virtual research facility, which, like its physical counterparts, provides tools for scientists to acquire reduced data products (thanks to our cadre of citizen scientists working to analyze images and produce results online), and also to participate in education and outreach activities either directly through CosmoQuest activities (such as CosmoAcademy and the Educators' Zone) or with the support of CosmoQuest. Here, we present our strategies to inspire, engage and support Subject Matter Experts (SMEs - Scientists, Engineers, Technologists and Mathematicians) in activities outside of their institutions, and beyond college classroom teaching. We provide support for SMEs who are interested in increasing the impacts of their science knowledge and expertise by interacting with people online, or in other venues outside of their normal work environment. This includes a broad spectrum of opportunities for those interested in hosting webinars; running short courses for the public; using Facebook, Twitter or other social media to communicate science; or other diverse activities such as supporting an open house, science fair, or star party. As noted by Katheryn Woods-Townsend and colleagues, "...face-to-face interactions with scientists allowed students to view scientists as approachable and normal people, and to begin to understand the range of scientific areas and careers that exist. Scientists viewed the scientist-student interactions as a vehicle for science communication" (2015). As CosmoQuest fosters these relationships, it We present a framework for SMEs which combine opportunities for continuing professional development (virtually and in person at conferences) with ongoing online support, creating a dynamic professional learning network. The goal of this is to deepen SME capacity-knowledge, attitudes and behaviors-both encouraging and empowering them to connect to broader audiences in new ways.

  19. Development of helium electron cyclotron wall conditioning on TCV (United States)

    Douai, D.; Goodman, T.; Isayama, A.; Fukumoto, M.; Wauters, T.; Sozzi, C.; Coda, S.; Blanchard, P.; Figini, L.; Garavaglia, S.; Miyata, Y.; Moro, A.; Ricci, D.; Silva, M.; Theiler, C.; Vartanian, S.; Verhaegh, K.; the EUROfusion MST1 Team; the TCV Team


    JT-60SA envisions electron cyclotron wall conditioning (ECWC), as wall conditioning method in the presence of the toroidal field to control fuel and impurity recycling and to improve plasma performance and reproducibility. This paper reports on Helium ECWC experiments on TCV in support of JT-60SA operation. Nearly sixty Helium conditioning discharges have been successfully produced in TCV, at a toroidal field B T  =  1.3 or 1.54 T, with gyrotrons at 82.7 GHz in X2 mode, mimicking ECWC operation in JT-60SA at the second harmonic of the EC wave. Discharge parameters were tuned in order to (i) minimize the time for the onset of ECWC plasmas, thus minimizing absorption of stray radiation by in-vessel components, (ii) improve discharge homogeneity by extending the discharge vertically and radially, and wall coverage, in particular of inboard surfaces where JT-60SA plasmas will be initiated, (iii) assess the efficiency of He-ECWC to deplete carbon walls from fuel. An optimized combination of vertical and radial magnetic fields, with amplitudes typically 0.1 to 0.6% of that of B T, has been determined, which resulted in lowest breakdown time, improved wall coverage and enhanced fuel removal. A standard ohmic D 2-plasma could be then sustained, whereas it would not have been possible without He-ECWC.

  20. Novel synthesis of thick wall coatings of titania supported Bi poisoned Pd catalysts and application in selective hydrogenation of acetylene alcohols in capillary microreactors. (United States)

    Cherkasov, Nikolay; Ibhadon, Alex O; Rebrov, Evgeny V


    Catalysis in microreactors allows reactions to be performed in a very small volume, reducing the environmental problems and greatly intensifying the processes through easy pressure control and the elimination of heat- and mass-transfer limitations. In this study, we report a novel method for the controlled synthesis of micrometre-thick mesoporous TiO2 catalytic coatings on the walls of long channels (>1 m) of capillary microreactors in a single deposition step. The method uses elevated temperature and introduces a convenient control parameter of the deposition rate (displacement speed controlled by a stepper motor), which allows deposition from concentrated and viscous sols without channel clogging. A capillary microreactor wall-coated with titania supported Bi-poisoned Pd catalyst was obtained using the method and used for the semihydrogenation of 2-methyl-3-butyn-2-ol providing 93 ± 1.5% alkene yield for 100 h without deactivation. Although the coating method was applied only for TiO2 deposition, it is nonetheless suitable for the deposition of volatile sols.

  1. Molded Concrete Center Mine Wall (United States)

    Lewis, E. V.


    Proposed semiautomatic system forms concrete-foam wall along middle of coal-mine passage. Wall helps support roof and divides passage into two conduits needed for ventilation of coal face. Mobile mold and concrete-foam generator form sections of wall in place.

  2. Solar walls in tsbi3 user's guide

    DEFF Research Database (Denmark)

    Wittchen, K.B.

    tsbi3 is a user-friendly and flexible computer program, which provides support to the design team in the analysis of the indoor climate and the energy performance of buildings. The solar wall module gives tsbi3 the capability of simulating solar walls and their interaction with the building....... This version, C, of tsbi3 is capable of simulating five types of solar walls say: mass-walls, Trombe-walls, double Trombe-walls, internally ventilated walls and solar walls for preheating ventilation air. The user's guide gives a description of the capabilities and how to simulate solar walls in tsbi3....

  3. Preparation of highly dispersed Pt-SnO{sub x} nanoparticles supported on multi-walled carbon nanotubes for methanol oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Hu Chuangang [College of Chemistry and Environmental Science, Henan Normal University, Engineering Technology Research Center of Motive Power and Key Materials of Henan Province, Xinxiang 453007 (China); Cao Yanxia [College of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450001 (China); Yang Lin, E-mail: [College of Chemistry and Environmental Science, Henan Normal University, Engineering Technology Research Center of Motive Power and Key Materials of Henan Province, Xinxiang 453007 (China); Bai Zhengyu; Guo Yuming; Wang Kui; Xu Pengle; Zhou Jianguo [College of Chemistry and Environmental Science, Henan Normal University, Engineering Technology Research Center of Motive Power and Key Materials of Henan Province, Xinxiang 453007 (China)


    To maximize the utilization of catalysts and thereby reduce the high price, a new strategy was developed to prepare highly dispersed Pt-SnO{sub x} nanoparticles supported on 8-Hydroxyquinoline (HQ) functionalized multi-walled carbon nanotubes (MWCNTs). HQ functionalized MWCNTs (HQ-MWCNTs) provide an ideal support for improving the utilization of platinum-based catalysts, and the introduction of SnO{sub x} to the catalyst prevents the CO poisoning effectively. The as-prepared catalysts are characterized by Transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. It is found that the HQ functionalization process preserves the integrity and electronic structure of MWCNTs, and the resulting Pt-SnO{sub x} particles are well dispersed on the HQ-MWCNTs with an average diameter of ca. 2.2 nm. Based on the electrochemical properties characterized by cyclic voltammetry and chronoamperometry, the Pt-SnO{sub x}/HQ-MWCNTs catalyst displays better electrocatalytic activity and stability for the methanol oxidation. It is worth mentioning that the forward peak current density of Pt-SnO{sub x}/HQ-MWCNTs catalyst is ca. 1.9 times of that of JM commercial 20% Pt/C catalyst, which makes it the preferable catalyst for direct methanol fuel cells.

  4. Mechanical Stimulation Modifies Canopy Architecture and Improves Volume Utilization Efficiency in Bell Pepper: Implications for Bioregenerative Life-support and Vertical Farming

    Directory of Open Access Journals (Sweden)

    Graham Thomas


    Full Text Available Mechanical stimuli or stress has been shown to induce characteristic morphogenic responses (thigmomorphogenesis in a range of crop species. The typical mechanically stimulated phenotype is shorter and more compact than non-mechanically stimulated plants. This dwarfing effect can be employed to help conform crop plants to the constraints of spaceflight and vertical agriculture crop production systems. Capsicum annum (cv. California Wonder plants were grown in controlled environment chambers and subjected to mechanical stimulation in the form of firm but gentle daily rubbing of internode tissue with a tightly wrapped cotton swab. Two studies were conducted, the first being a vegetative growth phase study in which plants were mechanically stimulated until anthesis. The second study carried the mechanical stimulation through to fruit set. The response during the vegetative growth experiment was consistent with other results in the literature, with a general reduction in all plant growth metrics and an increase in relative chlorophyll (SPAD content under mechanical stimulation. In the fruiting phase study, only height and stem thickness differed from the control plants. Using the data from the fruiting study, a rudimentary calculation of volume use efficiency (VUE improvements was conducted. Results suggest that VUE can be improved, particularly in terrestrial vertical agriculture systems that can take advantage of moderate height reductions by exploiting much greater vertical capacity in the production system. Mechanical stimulation can also improve VUE in spaceflight applications by reducing vertical system requirements or by expanding the species range that can be grown in a fixed production volume. Mechanical stimulation is also discussed as a microgravity countermeasure for crop plants.

  5. Topological valley transport at bilayer graphene domain walls. (United States)

    Ju, Long; Shi, Zhiwen; Nair, Nityan; Lv, Yinchuan; Jin, Chenhao; Velasco, Jairo; Ojeda-Aristizabal, Claudia; Bechtel, Hans A; Martin, Michael C; Zettl, Alex; Analytis, James; Wang, Feng


    Electron valley, a degree of freedom that is analogous to spin, can lead to novel topological phases in bilayer graphene. A tunable bandgap can be induced in bilayer graphene by an external electric field, and such gapped bilayer graphene is predicted to be a topological insulating phase protected by no-valley mixing symmetry, featuring quantum valley Hall effects and chiral edge states. Observation of such chiral edge states, however, is challenging because inter-valley scattering is induced by atomic-scale defects at real bilayer graphene edges. Recent theoretical work has shown that domain walls between AB- and BA-stacked bilayer graphene can support protected chiral edge states of quantum valley Hall insulators. Here we report an experimental observation of ballistic (that is, with no scattering of electrons) conducting channels at bilayer graphene domain walls. We employ near-field infrared nanometre-scale microscopy (nanoscopy) to image in situ bilayer graphene layer-stacking domain walls on device substrates, and we fabricate dual-gated field effect transistors based on the domain walls. Unlike single-domain bilayer graphene, which shows gapped insulating behaviour under a vertical electrical field, bilayer graphene domain walls feature one-dimensional valley-polarized conducting channels with a ballistic length of about 400 nanometres at 4 kelvin. Such topologically protected one-dimensional chiral states at bilayer graphene domain walls open up opportunities for exploring unique topological phases and valley physics in graphene.

  6. Vertical zonality of septal nectaries of Monocots

    Directory of Open Access Journals (Sweden)

    Аnastasiya Odintsova


    Full Text Available Considering the septal nectary as a system of exogenous cavities inside the ovary and taking account of possibilities of various ways of the formation of nectary walls we propose to apply the concept of vertical zonality to the analysis of the septal nectary structure. The comparative analysis of the gynoecium with septal nectaries must include data about the nectary vertical zones and its location in the structural zones of the gynoecium.

  7. Highly dispersed Pd nanoparticles supported on 1,10-phenanthroline-functionalized multi-walled carbon nanotubes for electrooxidation of formic acid (United States)

    Bai, Zhengyu; Guo, Yuming; Yang, Lin; Li, Lei; Li, Wujv; Xu, Pengle; Hu, Chuangang; Wang, Kui


    Functionalization step is generally prerequisite to immobilize metal nanoparticles on multi-walled carbon nanotubes (MWCNTs) for production of a high efficient electrocatalyst. We herein report a novel method to functionalize MWCNTs with 1,10-phenanthroline (phen-MWCNTs) as a catalyst support for Pd nanoparticles. Raman spectroscopic analysis results reveal that this phen functionalization method can preserve the integrity and electronic structure of MWCNTs and provide the highly effective functional groups on the surface for Pd nanoparticles. According to the transmission electron microscopy (TEM) measurements, the as-prepared Pd nanop articles are evenly deposited on the surface of the phen-MWCNTs without obvious agglomeration, and the average particle size of the Pd nanoparticles is 2.3 nm. Electrochemical measurements demonstrate that the as-prepared Pd/phen-MWCNTs catalyst has a better electrocatalytic activity and stability for the oxidation of formic acid than Pd catalyst on acid-treated MWCNTs. It is concluded that the as-prepared Pd/phen-MWCNTs would be a potential candidate as an anode electrocatalyst in direct formic acid fuel cell (DFAFC).

  8. A hybrid model of support vector regression with genetic algorithm for forecasting adsorption of malachite green onto multi-walled carbon nanotubes: central composite design optimization. (United States)

    Ghaedi, M; Dashtian, K; Ghaedi, A M; Dehghanian, N


    The aim of this work is the study of the predictive ability of a hybrid model of support vector regression with genetic algorithm optimization (GA-SVR) for the adsorption of malachite green (MG) onto multi-walled carbon nanotubes (MWCNTs). Various factors were investigated by central composite design and optimum conditions was set as: pH 8, 0.018 g MWCNTs, 8 mg L(-1) dye mixed with 50 mL solution thoroughly for 10 min. The Langmuir, Freundlich, Temkin and D-R isothermal models are applied to fitting the experimental data, and the data was well explained by the Langmuir model with a maximum adsorption capacity of 62.11-80.64 mg g(-1) in a short time at 25 °C. Kinetic studies at various adsorbent dosages and the initial MG concentration show that maximum MG removal was achieved within 10 min of the start of every experiment under most conditions. The adsorption obeys the pseudo-second-order rate equation in addition to the intraparticle diffusion model. The optimal parameters (C of 0.2509, σ(2) of 0.1288 and ε of 0.2018) for the SVR model were obtained based on the GA. For the testing data set, MSE values of 0.0034 and the coefficient of determination (R(2)) values of 0.9195 were achieved.

  9. Single-walled carbon nanotubes as supporting structures and stimulating materials for NG108-15 neuroblastoma-glioma hybrid culture cells (United States)

    Gheith, Muhammed Khameis

    Scope and method of study. Understanding the nature of interfacing inorganic materials, such as single-walled carbon nanotubes (SWNTs), with living cells is very crucial for the successful utilization of such man-made materials in biological and biomedical applications. The present study illustrates such a possible application where the mechanical and the electrical properties of SWNTs were utilized to design novel structures that were used as supporting platforms and stimulating substrates for NG108-15 hybrid neuronal cells. Composites of nanotubes were prepared using the layer-by-layer (LBL) assembly following the surface modification of the nanotubes with positively charged amphiphilic polymer that served as dispersing and stabilizing agent of the nanotubes. The functionalization of the nanotubes was characterized using Raman and absorption spectroscopic in addition to high-resolution transmission electron and atomic force microscopic techniques. The feasibility of the modified nanotube structures, films or freestanding, as supporting and stimulating substrates for neuronal growth and differentiation was investigated. Scanning electron and confocal microscopic techniques were mainly used to characterize the growth of the cells on the nanotube structures. Electrical coupling between the cells and the modified nanotube composites was investigated using the whole cell patch clamp technique. Findings and conclusions. The used polymer was seen to wrap around the nanotubes in a non-covalent attachment. Its presence on the nanotubes surface imparts a positive surface charge that facilitate the attachment of the cells to the formed nanotube structures. The LBL composites of the modified nanotubes were proven biocompatible to the NG108-15 cells growth and supported the long-term viability of these cells. Better cells differentiation was observed on the surface of the positively-charged nanotube films as compared to that on the surface of a negatively charged culture dish

  10. Ambiguous walls

    DEFF Research Database (Denmark)

    Mody, Astrid


    of “ambiguous walls” as a more “critical” approach to design [1]. The concept of ambiguous walls refers to the diffuse status a lumious and possibly responsive wall will have. Instead of confining it can open up. Instead of having a static appearance, it becomes a context over time. Instead of being hard...... and flat, “ambiguous walls” combine softness, tectonics and three-dimensionality. The paper considers a selection of luminious surfaces and reflects on the extent of their ambiguous qualities. Initial ideas for new directions for the wall will be essayed through the discussion....

  11. Experimental Assessment of Mechanical Night Ventilation on Inner Wall Surfaces

    DEFF Research Database (Denmark)

    Wenhui, Ji; Heiselberg, Per Kvols; Wang, Houhua


    The cooling potential of night ventilation largely depends on the heat exchange at the internal room surfaces. During night time, increased heat transfer on a vertical wall is expected due to cool supply air that flows along the internal wall surface from the top of the wall. This paper presents ...

  12. Computations of Vertical Displacement Events with Toroidal Asymmetry (United States)

    Sovinec, C. R.; Bunkers, K. J.


    Nonlinear numerical MHD modeling with the NIMROD code [] is being developed to investigate asymmetry during vertical displacement events. We start from idealized up/down symmetric tokamak equilibria with small levels of imposed toroidally asymmetric field errors. Vertical displacement results when removing current from one of the two divertor coils. The Eulerian reference-frame modeling uses temperature-dependent resistivity and anisotropic thermal conduction to distinguish the hot plasma region from surrounding cold, low-density conditions. Diffusion through a resistive wall is slow relative to Alfvenic scales but much faster than resistive plasma diffusion. Loss of the initial edge pressure and current distributions leads to a narrow layer of parallel current, which drives low-n modes that may be related to peeling-dominated ELMs. These modes induce toroidal asymmetry in the conduction current, which connects the simulated plasma to the wall. Work supported by the US DOE through Grant Numbers DE-FG02-06ER54850 and DE-FC02-08ER54975.

  13. An electrochemical sensor prepared by sonochemical one-pot synthesis of multi-walled carbon nanotube-supported cobalt nanoparticles for the simultaneous determination of paracetamol and dopamine

    Energy Technology Data Exchange (ETDEWEB)

    Kutluay, Aysegul; Aslanoglu, Mehmet, E-mail:


    Highlights: • A GCE was modified with carbon nanotubes and cobalt nanoparticles. • The composite material was obtained using an ultrasonic chemical deposition method. • The CoNPs/MWCNT/GCE was applied for the simultaneous determination of PAR and DA. • The presence of AA and UA did not affect the responses of PAR and DA. • Lower detection limits were obtained using the CoNPs/MWCNT/GCE. - Abstract: Multi-walled carbon nanotubes (MWCNTs) functionalized by cobalt nanoparticles were obtained using a single step chemical deposition method in an ultrasonic bath. The composite material was characterized using scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). The electroactivity of the cobalt-functionalized MWCNTs was assessed in respect to the electrooxidation of paracetamol (PAR) and dopamine (DA). It was found that the carbon nanotube supported cobalt nanoparticles have significantly higher catalytic properties. The proposed electrode has been applied for the simultaneous determination of PAR and DA. The modified electrode could resolve the overlapped voltammetric waves of PAR and DA into two well-defined voltammetric peaks with peak to peak separation of about 203 mV. On the other hand, the presence of potential drug interfering compounds AA and UA did not affect the voltammetric responses of PAR and DA. The current of oxidation peaks showed a linear dependent on the concentrations of PAR and DA in the range of 5.2 × 10{sup −9}–4.5 × 10{sup −7} M (R{sup 2} = 0.9987) and 5.0 × 10{sup −8}–3.0 × 10{sup −6} M (R{sup 2} = 0.9999), respectively. The detection limits of 1.0 × 10{sup −9} M and 1.5 × 10{sup −8} M were obtained for PAR and DA, respectively. The proposed electrode showed good stability (peak current change: 4.9% with and RSD of 2.6% for PAR; 5.5% with and RSD of 3.0% for DA over 3 weeks), reproducibility (RSD 2.3% for PAR and RSD 1.5% for DA), repeatability (RSD 2.25% for PAR and RSD 2.50% for DA) and

  14. Effect of multi-wall carbon nanotubes supported nano-nickel and TiF{sub 3} addition on hydrogen storage properties of magnesium hydride

    Energy Technology Data Exchange (ETDEWEB)

    Su, Wei; Zhu, Yunfeng, E-mail:; Zhang, Jiguang; Liu, Yana; Yang, Yang; Mao, Qifeng; Li, Liquan


    Multi-wall carbon nanotubes supported nano-nickel (Ni/MWCNTs) with superior catalytic effects was introduced to magnesium hydride by the process of hydriding combustion synthesis (HCS) and mechanical milling (MM). The effect of different Ni/MWCNTs contents (5 wt.%, 10 wt.%, 15 wt.%, 20 wt.%) on the hydrogenation and dehydrogenation properties of the composite was investigated systematically. It is revealed that Mg{sub 85}-(Ni/MWCNTs){sub 15} composite shows the best comprehensive hydrogen storage properties, which absorbs 5.68 wt.% hydrogen within 100 s at 373 K and releases 4.31 wt.% hydrogen within 1800 s at 523 K under initial hydrogen pressures of 3.0 and 0.005 MPa, respectively. The in situ formed nano-Mg{sub 2}Ni and MWCNTs have excellent catalytic effect on the hydrogenation and dehydrogenation performances of MgH{sub 2}. To further improve the hydrogen absorption/desorption properties, TiF{sub 3} was added to the Mg–Ni/MWCNTs system. The result shows that TiF{sub 3} addition has little influence on the thermodynamic performance, but affects greatly the kinetic properties. The Mg{sub 85}-(Ni/MWCNTs){sub 15}-TiF{sub 3} composite exhibits an appreciably enhanced hydrogen desorption performance at low temperature, and the hydrogen desorption capacity within 1800 s at 473 K for the TiF{sub 3}-added composite is approximately four times the capacity of Mg{sub 85}-(Ni/MWCNTs){sub 15} under the same condition. The catalytic effects during hydrogenation and dehydrogenation have been discussed in the study. - Highlights: • The nanosized Ni/MWCNTs catalyst was successfully prepared. • Ni/MWCNTs shows superior catalytic effect on H absorption/desorption of Mg. • Mg{sub 85}-(Ni/MWCNTs){sub 15} composite shows the best hydrogen storage properties. • Ni/MWCNTs coupling with TiF{sub 3} improves the hydriding/dehydriding properties largely.

  15. Wall Art (United States)

    McGinley, Connie Q.


    The author of this article, an art teacher at Monarch High School in Louisville, Colorado, describes how her experience teaching in a new school presented an exciting visual challenge for an art teacher--monotonous brick walls just waiting for decoration. This school experienced only minimal instances of graffiti, but as an art teacher, she did…

  16. Acquired vertical accommodative vergence. (United States)

    Klein-Scharff, Ulrike; Kommerell, Guntram; Lagrèze, Wolf A


    Vertical accommodative vergence is an unusual synkinesis in which vertical vergence is modulated together with accommodation. It results from a supranuclear miswiring of the network normally conveying accommodative convergence. So far, it is unknown whether this condition is congenital or acquired. We identified an otherwise healthy girl who gradually developed vertical accommodative vergence between five to 13 years of age. Change of accommodation by 3 diopters induced a vertical vergence of 10 degrees. This observation proves that the miswiring responsible for vertical accommodative vergence must not necessarily be congenital, but can be acquired. The cause and the mechanism leading to vertical accommodative vergence are yet unknown.

  17. Wall Layers (United States)


    Sydney, Australia. December 6, 1990. Lumley, J. L. A dynamical-systems-theory approach to the wall region. Environmental Engineering Laboratory, CSIRO...Nonlinear Science. Holmes, P. Editor in Chief, Nonlinear Scinece Today. Holmes, P. Reviewer for Physica D, J. Sound Vib., J. Phys., Q. Appl. Math, Phys...Spring, 1994; Organizing committee member. Holmes, P. Editorial Board Member: Archive for Rational Mechanics and Analysis; Journal of Nonlinear Scinece


    CERN Multimedia


    The FIRE AND RESCUE Group of TIS Commission informs that the climbing wall in the yard of the Fire-fighters Station, is intended for the sole use of the members of that service, and recalls that access to this installation is forbidden for safety reasons to all persons not belonging to the Service.CERN accepts no liability for damage or injury suffered as a result of failure to comply with this interdiction.TIS/DI

  19. Vertical axis wind turbines (United States)

    Krivcov, Vladimir [Miass, RU; Krivospitski, Vladimir [Miass, RU; Maksimov, Vasili [Miass, RU; Halstead, Richard [Rohnert Park, CA; Grahov, Jurij [Miass, RU


    A vertical axis wind turbine is described. The wind turbine can include a top ring, a middle ring and a lower ring, wherein a plurality of vertical airfoils are disposed between the rings. For example, three vertical airfoils can be attached between the upper ring and the middle ring. In addition, three more vertical airfoils can be attached between the lower ring and the middle ring. When wind contacts the vertically arranged airfoils the rings begin to spin. By connecting the rings to a center pole which spins an alternator, electricity can be generated from wind.

  20. Jamming of Cylindrical Grains in Featureless Vertical Channels (United States)

    Baxter, G. William; Barr, Nicholas; Weible, Seth; Friedl, Nicholas


    We study jamming of low aspect-ratio cylindrical Delrin grains falling through a featureless vertical channel. With a grain height less than the grain diameter, these grains resemble aspirin tablets, poker chips, or coins. Unidisperse grains are allowed to fall under the influence of gravity through a uniform channel of square cross-section where the channel width is greater than the grain size and constant along the length of the channel. Channel widths are chosen so that no combination of grain heights and diameters is equal to the channel width. Collections of grains sometimes form jams, stable structures in which the grains are supported by the channel walls and not by grains or walls beneath them. The probability of a jam occurring and the jam's strength are influenced by the grain dimensions and channel width. We will present experimental measurements of the jamming probability and jam strength and discuss the relationship of these results to other experiments and theories. Supported by an Undergraduate Research Grant from Penn State Erie, The Behrend College

  1. Jamming of Monodisperse Cylindrical Grains in Featureless Vertical Channels (United States)

    Friedl, Nicholas; Baxter, G. William


    We study jamming of low aspect-ratio cylindrical Delrin grains falling through a featureless vertical channel under the influence of gravity. These grains have an aspect-ratio less than two (H/D aspirin tablets, 35mm film canisters, poker chips, or coins. Monodisperse grains are allowed to fall under the influence of gravity through a uniform channel of square cross-section where the channel width is greater than the grain size and constant along the length of the channel. No combination of grain heights and diameters is equal to the channel width. Collections of grains sometimes form jams, stable structures in which the grains are supported by the channel walls and not by grains or walls beneath them. The probability of a jam occurring and the jam's strength are influenced by the grain dimensions and channel width. We will present experimental measurements of the jamming probability and jam strength and discuss the relationship of these results to other experiments and theories. Supported by an Undergraduate Research Grant from Penn State Erie, The Behrend College.

  2. Vertical Carbon Nanotube Device in Nanoporous Templates (United States)

    Maschmann, Matthew Ralph (Inventor); Fisher, Timothy Scott (Inventor); Sands, Timothy (Inventor); Bashir, Rashid (Inventor)


    A modified porous anodic alumina template (PAA) containing a thin CNT catalyst layer directly embedded into the pore walls. CNT synthesis using the template selectively catalyzes SWNTs and DWNTs from the embedded catalyst layer to the top PAA surface, creating a vertical CNT channel within the pores. Subsequent processing allows for easy contact metallization and adaptable functionalization of the CNTs and template for a myriad of applications.

  3. Design of Vertical Wall Caisson Breakwaters using Partial Safety Factors

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Sørensen, John Dalsgaard


    The paper presents a new system for implementation of target reliability in caisson breakwater designs by means of partial safety factors. The development of the system is explained, and tables of partial safety factors are presented for important overall stability failure modes related to caisso...

  4. Horizontal Coherence of Wave Forces on Vertical Wall Breakwaters

    DEFF Research Database (Denmark)

    Archetti, R.; Frigaard, Peter; Lamberti, A.


    of breaking waves for increasing wave height are estimated and compared with existing empirical formulae. The horizontal dimension of the breaker is investigated using two different methodologies: the first analyses the decreasing of the highest 1/250 force with increasing horizontal dimension of the caisson......, with special attention to the effects of wave spreading, and the second analyses the spatial correlation of impulsive force per unit length along the breakwater....

  5. Horizontal Coherence of Wave Forces on Vertical Wall Breakwaters

    DEFF Research Database (Denmark)

    Archetti, Renata; Lamberti, Alberto; Martinelli, Luca


    Evaluation of spatial coherence of breaking waves is of great importance and of recent interest.......Evaluation of spatial coherence of breaking waves is of great importance and of recent interest....

  6. Representation and Reconstruction of Triangular Irregular Networks with Vertical Walls

    NARCIS (Netherlands)

    Gorte, B.G.H.; Lesparre, J.


    Point clouds obtained by aerial laser scanning are a convenient input source for high resolution 2.5d elevation models, such as the Dutch AHN-2. More challenging is the fully automatic reconstruction of 3d city models. An actual demand for a combined 2.5d terrain and 3d city model for an urban

  7. Falling walls

    CERN Multimedia

    It was 20 years ago this week that the Berlin wall was opened for the first time since its construction began in 1961. Although the signs of a thaw had been in the air for some time, few predicted the speed of the change that would ensue. As members of the scientific community, we can take a moment to reflect on the role our field played in bringing East and West together. CERN’s collaboration with the East, primarily through links with the Joint Institute for Nuclear Research, JINR, in Dubna, Russia, is well documented. Less well known, however, is the role CERN played in bringing the scientists of East and West Germany together. As the Iron curtain was going up, particle physicists on both sides were already creating the conditions that would allow it to be torn down. Cold war historian Thomas Stange tells the story in his 2002 CERN Courier article. It was my privilege to be in Berlin on Monday, the anniversary of the wall’s opening, to take part in a conference entitled &lsquo...

  8. Facile synthesis of palladium nanoparticles supported on multi-walled carbon nanotube for efficient hydrogenation of biomass-derived levulinic acid

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Kai, E-mail:; Lafleur, Todd [Lakehead University, Department of Chemistry (Canada); Liao, Jiayou [Tianjin University, School of Chemical Engineering and Technology (China)


    Different loading of palladium (Pd) nanoparticles were successfully fabricated on multi-walled carbon nanotubes using Pd acetylacetonate as the precursor via a simple liquid impregnation method. The crystal phase, morphology, textural structure and the chemical state of the resulting Pd nanoparticles (Pd/CNT) catalysts were studied and the characterization results indicated that the uniform dispersion of small Pd nanoparticles with the size range of 1.0-4.5 nm was achieved. The synthesized Pd/CNT catalysts exhibited efficient performance for the catalytic hydrogenation of biomass-derived levulinic acid into biofuel {gamma}-valerolactone. In comparison with the commercial 5 wt% Pd/C and the 5 wt% Pd/CNT catalyst prepared by Pd nitrate precursor, much higher activities were achieved, whereas the biofuel {gamma}-valerolactone was highly produced with 56.3 % yield at 57.6 % conversion of levulinic acid on the 5 wt% Pd/CNT catalyst under mild conditions. The catalyst developed in this work may be a good candidate for the wide applications in the hydrogenation.

  9. 3D Bearing Capacity of Structured Cells Supported on Cohesive Soil: Simplified Analysis Method

    Directory of Open Access Journals (Sweden)

    Martínez-Galván Sergio Antonio


    Full Text Available In this paper a simplified analysis method to compute the bearing capacity of structured cell foundations subjected to vertical loading and supported in soft cohesive soil is proposed. A structured cell is comprised by a top concrete slab structurally connected to concrete external walls that enclose the natural soil. Contrary to a box foundation it does not include a bottom slab and hence, the soil within the walls becomes an important component of the structured cell. This simplified method considers the three-dimensional geometry of the cell, the undrained shear strength of cohesive soils and the existence of structural continuity between the top concrete slab and the surrounding walls, along the walls themselves and the walls structural joints. The method was developed from results of numerical-parametric analyses, from which it was found that structured cells fail according to a punching-type mechanism.

  10. Structure of diffusion flames from a vertical burner (United States)

    Mark A. Finney; Dan Jimenez; Jack D. Cohen; Isaac C. Grenfell; Cyle Wold


    Non-steady and turbulent flames are commonly observed to produce flame contacts with adjacent fuels during fire spread in a wide range of fuel bed depths. A stationary gas-fired burner (flame wall) was developed to begin study of flame edge variability along an analagous vertical fuel source. This flame wall is surrogate for a combustion interface at the edge of a deep...

  11. Root Growth and Water distribution in living walls

    DEFF Research Database (Denmark)

    Jørgensen, Lars

    Living walls is a way of bringing plants and green areas into cities, and offer both positive environmental and aesthetical effects. A prerequisite for optimal performance of a living wall is that the plant cover is properly established why the individual plant should have optimal conditions...... walls; the vertical orientation of the growing medium, plants are growing vertically above or below each other in a limited rooting volume; there is an increased exposure to weather and the plants can react differently to water conditions and competition from other plants. Plant growth is the core...

  12. Vertical atlantoaxial dislocation


    Ramaré, S.; Lazennec, J. Y.; Camelot, C.; Saillant, G.; Hansen, S.; Trabelsi, R.


    An unusual case of vertical atlantoaxial dislocation without medulla oblongata or spinal cord injury is reported. The pathogenic process suggested occipito-axial dislocation. The case was treated surgically with excellent results on mobility and pain.

  13. Coordination in vertical jumping

    NARCIS (Netherlands)

    Bobbert, Maarten F.; van Ingen Schenau, Gerrit Jan


    The present study was designed to investigate for vertical jumping the relationships between muscle actions, movement pattern and jumping achievement. Ten skilled jumpers performed jumps with preparatory countermovement. Ground reaction forces and cinematographic data were recorded. In addition,

  14. Ion transfer kinetics at the interface between two immiscible electrolyte solutions supported on a thick-wall micro-capillary. A mini review

    Czech Academy of Sciences Publication Activity Database

    Mareček, Vladimír; Samec, Zdeněk


    Roč. 1, č. 1 (2017), s. 133-139 ISSN 2451-9103 R&D Projects: GA ČR GA13-04630S Institutional support: RVO:61388955 Keywords : Experimental ion transfer kinetics * ITIES * Theoretical aspects Subject RIV: CG - Electrochemistry OBOR OECD: Electrochemistry (dry cells, batteries, fuel cells, corrosion metals, electrolysis)

  15. Hybrid vertical cavity laser

    DEFF Research Database (Denmark)

    Chung, Il-Sug; Mørk, Jesper


    A new hybrid vertical cavity laser structure for silicon photonics is suggested and numerically investigated. It incorporates a silicon subwavelength grating as a mirror and a lateral output coupler to a silicon ridge waveguide.......A new hybrid vertical cavity laser structure for silicon photonics is suggested and numerically investigated. It incorporates a silicon subwavelength grating as a mirror and a lateral output coupler to a silicon ridge waveguide....

  16. Composition of vertical gardens


    Sandeva, Vaska; Despot, Katerina


    Vertical gardens are fully functional gardens in areas where there is less oxygen and space, ideal for residential and urban cities where there is no vegetation; occupy a special place in interiors furniture. The gardens occupy an important aesthetic problem. Aesthetic task in vertical gardens can be achieved by forming sectors of identification in the urban landscape through the choice of a particular plant spatial composition and composition, to create comfort and representation in commu...

  17. Turbulent channel flows over complex walls (United States)

    Rosti, Marco Edoardo; Brandt, Luca


    We perform numerical simulations of turbulent channel flows over porous walls and deformable hyper-elastic walls. The flow over porous walls is simulated using volume-averaged Navier ``Stokes equations within the porous layers, while the multiphase flow over deformable walls is solved with a one-continuum formulation which allows the use of a fully Eulerian formulation. New insights on the effect of these complex walls on the turbulent flows in terms of friction, statistics and flow structures are discussed using a number of post-processing techniques. The turbulent flow in the channel is affected by the porous and moving walls in a similar manner even at low values of porosity and elasticity due to the non-zero fluctuations of vertical velocity at the interface that influence the flow dynamics. The near-wall streaks and the associated quasi-streamwise vortices are strongly reduced near porous and deformable isotropic wall while the flow becomes more correlated in the spanwise direction. On the contrary, an opposite behavior is noticed in the case of anisotropic porous layers, with an increase of streamwise correlation due to a strengthening of the low- and high-speed streaks.

  18. Self rating of health is associated with stressful life events, social support and residency in East and West Berlin shortly after the fall of the wall. (United States)

    Hillen, T; Schaub, R; Hiestermann, A; Kirschner, W; Robra, B P


    To compare the health status and factors influencing the health of populations that had previously lived under different political systems. Cross sectional health and social survey using postal interviews. The relation between self reported health and psychosocial factors (stressful life events, social support, education, health promoting life style and health endangering behaviour) was investigated. To determine East-West differences a logistic regression model including interaction terms was fitted. East and West Berlin shortly after reunification 1991. Representative sample of 4430 Berlin residents aged 18 years and over (response rate 63%). Of all respondents, 15.4% rated their health as unsatisfactory. Residents of East Berlin rated their health more frequently as unsatisfactory than residents of West Berlin (Or(age adjusted)= 1.29, 95%CI 1.08, 1.52), these differences occurred predominantly in the over 60 years age group. Logistic regression showed significant independent effects of stressful life events, social support, education, and health promoting life style on self rated health. The effects of education and health promoting life style were observed to be more pronounced in the western part of Berlin. Old age and female sex showed a stronger association with unsatisfactory health status in the eastern part of Berlin. For subjects aged over 60 years there was evidence that living in the former East Berlin had an adverse effect on health compared with West Berlin. The impact of education and a health promoting lifestyle on self rated health seemed to be weaker in a former socialist society compared with that of a Western democracy. This study supports an "additive model" rather than a "buffering model" in explaining the effects of psychosocial factors on health.

  19. Voltammetric and impedimetric properties of nano-scaled -Fe2O3 catalysts supported on multi-walled carbon nanotubes: catalytic detection of dopamine

    CSIR Research Space (South Africa)

    Adekunle, AS


    Full Text Available been used to investigate the role of neurotransmitters in the brain due to their electroactive nature [23]. In this study, we report the voltammetric detection of dopamine using easily prepared nano- scaled iron oxide (Fe2O3) catalyst supported... concentration of standard dopamine solution, and made to volume with phosphate buffer pH 7.0. The concentration of each test aliquot solution was determined using square wave voltammetry. Four different injections from the same batch were analysed using...

  20. One-pot synthesis of Pd@PtNi core-shell nanoflowers supported on the multi-walled carbon nanotubes with boosting activity toward oxygen reduction in alkaline electrolyte (United States)

    Liu, Sa; Wang, Yan; Liu, Liwen; Li, Mengli; Lv, Wenjie; Zhao, Xinsheng; Qin, Zhenglong; Zhu, Ping; Wang, Guoxiang; Long, Zhouyang; Huang, Fangmin


    Pt-based nanocrystals with controlled morphologies and structures are one of most promising electrocatalysts for oxygen reduction reaction (ORR). Herein, a facile one-pot wet-chemical method is developed to synthesize Pd@PtNi core-shell nanoflowers (CSNFs) supported on the multi-walled carbon nanotubes (MWNCTs). Brij 58 is demonstrated as a structure-directing agent to generate the nanoflower and ascorbic acid acts as a reductant to form a core-shell structure. By tuning the molar ratio of Pd and Pt, Pd@PtNi/MWCNTs CSNFs show obviously improved ORR activity and durability in alkaline electrolyte compared with PtNi/MWCNTs nanoflowers and commercial Pt/C. The results illustrate that the core-shell structure and porous feature of nanoflower are both beneficial to the enhancement of the catalytic properties.

  1. Application of flexi-wall in noise barriers renewal

    Directory of Open Access Journals (Sweden)

    B. Daee


    Full Text Available This paper presents an experimental study on structural performance of an innovative noise barrier consisting of poly-block, light polyurethane foam (LPF and polyurea. This wall system (flexi-wall is intended to be employed as a vertical extension to existing noise barriers (sound walls in an accelerated construction method. To aid in the wall design, several mechanical tests were conducted on LPF specimens and two full-scale walls were then fabricated employing the same LPF material. The full-scale walls were subjected to lateral loading in order to establish their lateral resistance. A cyclic fatigue test was also performed on a full-scale flexi-wall in order to evaluate the performance of the wall under a repetitive loading condition. The results of the experiments indicated the suitability of flexi-wall in accelerated construction and confirmed that the structural performance of the wall system under lateral loading is satisfactory for the sound wall application. The experimental results were discussed and a preliminary design procedure for application of flexi-wall in sound wall applications was also developed.

  2. Reinforcement contribution to the behavior of low-rise concrete walls

    Directory of Open Access Journals (Sweden)

    Julian Carrillo

    Full Text Available Based on steel strains recorded during shake table tests of six wall specimens, the effect and contribution of steel reinforcement to peak shear strength and displacement capacity of low-rise concrete walls is assessed and discussed. The experimental program included four variables such as wall geometry, concrete type, web steel ratio and type of web reinforcement. Wall response was assessed through effective steel strains in vertical reinforcement, efficiency factors of wall reinforcement, contribution of web horizontal reinforcement to wall shear strength, and the effect of type of web reinforcement to wall displacement.

  3. Solar walls in tsbi3 user's guide

    DEFF Research Database (Denmark)

    Wittchen, K.B.

    tsbi3 is a user-friendly and flexible computer program, which provides support to the design team in the analysis of the indoor climate and the energy performance of buildings. The solar wall module gives tsbi3 the capability of simulating solar walls and their interaction with the building...

  4. The State of the GeoWall (United States)

    Morin, P. J.; Leigh, J.; van Keken, P.; Johnson, A.


    The GeoWall stereo projection technology has been widely adopted within Earth Science. Over 20,000 undergraduate students per year use a GeoWall in classroom and lab settings at over 80 institutions around the world using over 200 GeoWalls. We believe that critical mass for this technology has been reached in the Earth Science. Many collaborations have been initiated. With Iris, GeoWall is exploring new ways to monitor seismic networks in real-time and to visualize extremely large, whole Earth seismic simulations. We are also working with a number of drilling organizations including JOI, DOSECC and LacCore to bring modern visualization technology to core interpretation and drill site selection. Also, over 15 museums now have or are building GeoWalls for informal education. Much of the science that is being performed on the GeoWall is finding its way directly into the classroom and science museum. One of the success stories has been the GeoWall Consortium's interaction with industry. The basic hardware for the GeoWall has been spun off to companies that now sell variations of the hardware. In addition, many software companies including ESRI and Dynamic Graphics have added support for the GeoWall in their products. The future of GeoWall is four fold. Curriculum development will bring more material to all GeoWall users. Assessment of the curriculum and educational psychology will give us GeoWall best practices. In technology development, the GeoWall 2 is a 20+ million pixel, tiled display which brings more resolution to the Earth Sciences than ever. To support research the consortium is developing a volume rendering application to visualize extremely large datasets.

  5. Theoretical study of solar light reflectance from vertical snow surfaces

    Directory of Open Access Journals (Sweden)

    O. V. Nikolaeva


    Full Text Available The influence of horizontal and vertical inhomogeneity of snow surfaces on solar light reflectance is studied using the radiative transfer theory (RTT. We compared 1-D RTT and 2-D RTT and found that large errors are produced if the 1-D RTT is used for the calculation of the snow reflection function (and, therefore, also in the retrievals of the snow grain radii in 2-D measurement geometries. Such 2-D geometries are common in the procedures for the determination of the effective snow grain radii using near-infrared photography and spectroscopy of vertical snow walls. In particular, we have considered three cases for the numerical calculations: (1 the case with no black film; (2 the case with a black film at the pit's bottom; (3 the case with a black film at the pit's bottom and also at one of the vertical snow walls.

  6. Comparison of Vertical Light Wooden Constructions Insulated by Straw Bales

    Directory of Open Access Journals (Sweden)

    Kováč Miloslav


    Full Text Available The main task of configuring engineer by designing enclosure construction is to setup performances of the wall to the best options for existing conditions of the structure. Selecting and adjusting bearing elements of perimeter wall is the first step, however appropriateness and position of chosen materials has major influence on technical properties and architectural expression of structure. Besides light vertical constructions (LVC there are light wooden constructions from glued elements (LPVC, heavy vertical constructions (HVC and prefabricated vertical constructions (PVC. All types have specifications allowing alternatives in terms of layer structure and bearing elements position. Each type is considered in terms of: structure – 2D drawing and 3D model, thermal insulation, overall heat transfer coefficient, architectural examination.

  7. Comparison of Vertical Light Wooden Constructions Insulated by Straw Bales (United States)

    Kováč, Miloslav


    The main task of configuring engineer by designing enclosure construction is to setup performances of the wall to the best options for existing conditions of the structure. Selecting and adjusting bearing elements of perimeter wall is the first step, however appropriateness and position of chosen materials has major influence on technical properties and architectural expression of structure. Besides light vertical constructions (LVC) there are light wooden constructions from glued elements (LPVC), heavy vertical constructions (HVC) and prefabricated vertical constructions (PVC). All types have specifications allowing alternatives in terms of layer structure and bearing elements position. Each type is considered in terms of: structure - 2D drawing and 3D model, thermal insulation, overall heat transfer coefficient, architectural examination.

  8. Diel vertical migrat..

    African Journals Online (AJOL)


    Jan 24, 2002 ... crustacean zooplankton but also in a Wide array of different marine zooplankton groups. (Russell 1927, McLaren 1963). Thus there is no doubt that ..... cooperation during field work and for their fruitful discussion on the draft manuscript. REFERENCES. Bayly lAE 1986 Aspects of diel vertical migration in ...

  9. Vertical market participation

    DEFF Research Database (Denmark)

    Schrader, Alexander; Martin, Stephen


    Firms that operate at both levels of vertically related Cournot oligopolies will purchase some input supplies from independent rivals, even though they can produce the good at a lower cost, driving up input price for nonintegrated firms at the final good level. Foreclosure, which avoids this stra...... this strategic behavior, yields better market performance than Cournot beliefs...

  10. Hunting Voronoi vertices

    NARCIS (Netherlands)

    Ferrucci, V.; Overmars, Mark; Rao, A.; Vleugels, J.


    Given three objects in the plane, a Voronoi vertex is a point that is equidistant simultaneously from each. In this paper, we consider the problem of computing Voronoi vertices for planar objects of xed but possibly unknown shape; we only require the ability to query the closest point on an object

  11. Vertical shaft windmill (United States)

    Grana, D. C.; Inge, S. V., Jr. (Inventor)


    A vertical shaft has several equally spaced blades mounted. Each blade consists of an inboard section and an outboard section skew hinged to the inboard section. The inboard sections automatically adjust their positions with respect to the fixed inboard sections with changes in velocity of the wind. This windmill design automatically governs the maximum rotational speed of shaft.

  12. Vertical gastroplasty: evolution of vertical banded gastroplasty. (United States)

    Mason, E E; Doherty, C; Cullen, J J; Scott, D; Rodriguez, E M; Maher, J W


    The objective of this paper is to summarize the goals, technical requirements, advantages, and potential risks of gastroplasty for treatment of severe obesity. Gastroplasty is preferred to more complex operations, as it preserves normal digestion and absorption and avoids complications that are peculiar to exclusion operations. The medical literature and a 30-year experience at the University of Iowa Hospitals and Clinics (UIHC) provides an overview of vertical banded gastroplasty (VBG) evolution. Preliminary 10-year results with the VBG technique currently used at UIHC are included. At UIHC the VBG is preferred to other gastroplasties because it provides weight control that extends for at least 10 years and the required objective, intraoperative quality control required for a low rate of reoperation. It is recommended that modifications of the operative technique not be attempted until a surgeon has had experience with the standardized operation--and then only under a carefully designed protocol. Realistic goals for surgery and criteria of success influence the choice of operation and the optimum, lifelong risk/benefit ratio. In conclusion, VBG is a safe, long-term effective operation for severe obesity with advantages over complex operations and more restrictive simple operations.

  13. post chf vertical flow

    African Journals Online (AJOL)


    penetration fraction. P(E1 ≥ E2) probability distribution function .... generated, applied to a control volume whose boundary is coincident with .... that a drop reaches the wall is given by the probability that (Eb1 ≥ Ew) or F(Eb1 ≥ Ew). A negative exponential relation is postulated flour this probability. Thus,. (Eb1 ≥ Ew) = (10).

  14. Innovative Composite Wall System for Sheathing Masonry Walls

    Energy Technology Data Exchange (ETDEWEB)

    Wendt, Robert L. [Oak Ridge National Lab., TN (United States); Cavallo, James [Argonne National Lab., IL (United States)


    Existing Housing - Much of the older multifamily housing stock in the United States includes units in structures with uninsulated masonry walls. Included in this stock are two- and three-story walk-up apartments, larger apartment complexes, and public housing (both high- rise and townhouse). This older multifamily housing has seen years of heavy use that may have left the plaster wall marred or damaged. Long- term building settlement or movement may have cracked the plaster, sometimes severely. Moisture from invented kitchens and baths may have caused condensation on uninsulated exterior walls. At best this condensation has left stains on the paint or wallpaper. At worst it has supported mold and mildew growth, fouling the air and creating unhealthy living conditions. Deteriorating plaster and flaking paint also result from wet walls. The presence of flaking, lead-based paint in older (pre-1978) housing is a major public health concern. Children can suffer permanent mental handicaps and psychological disorders if they are subjected to elevated levels of lead, while adults can suffer hypertension and other maladies. Studies have found that, in some urban communities with older housing stocks, over 35% of children tested have elevated blood lead levels (Hastings, et al.: 1997). Nationally, nearly 22% of black, non-hispanic children living in pre-1946 housing were found to have elevated levels of lead in their blood (MWWR Article: February 21,1997). The deterioration of many of these walls is to the point that lead can freely enter the living space.

  15. Computer-controlled wall servicing robot

    Energy Technology Data Exchange (ETDEWEB)

    Lefkowitz, S. [Pentek, Inc., Corapolis, PA (United States)


    After four years of cooperative research, Pentek has unveiled a new robot with the capability to automatically deliver a variety of cleaning, painting, inspection, and surveillance devices to large vertical surfaces. The completely computer-controlled robot can position a working tool on a 50-foot tall by 50-foot wide vertical surface with a repeatability of 1/16 inch. The working end can literally {open_quotes}fly{close_quotes} across the face of a wall at speed of 60 per minute, and can handle working loads of 350 pounds. The robot was originally developed to decontaminate the walls of reactor fueling cavities at commercial nuclear power plants during fuel outages. If these cavities are left to dry after reactor refueling, contamination present in the residue could later become airborne and move throughout the containment building. Decontaminating the cavity during the refueling outage reduces the need for restrictive personal protective equipment during plant operations to limit the dose rates.

  16. Thermal conductivity of low temperature grown vertical carbon nanotube bundles measured using the three-? method

    NARCIS (Netherlands)

    Vollebregt, S.; Banerjee, S.; Beenakker, K.; Ishihara, R.


    The thermal conductivity of as-grown vertical multi-walled carbon nanotubes (CNT) bundles fabricated at low temperature (500?°C) was measured using a vertical 3?-method. For this, CNT were selectively grown inside an oxide opening and sandwiched between two metal electrodes. The validity of the

  17. Robotic platform for traveling on vertical piping network (United States)

    Nance, Thomas A; Vrettos, Nick J; Krementz, Daniel; Marzolf, Athneal D


    This invention relates generally to robotic systems and is specifically designed for a robotic system that can navigate vertical pipes within a waste tank or similar environment. The robotic system allows a process for sampling, cleaning, inspecting and removing waste around vertical pipes by supplying a robotic platform that uses the vertical pipes to support and navigate the platform above waste material contained in the tank.

  18. Free convection of Walter's fluid flow in a vertical double-passage ...

    African Journals Online (AJOL)


    Huilgol, R.R. and Phan-Thien, N., 1997. Fluid mechanics of viscoelasticity, Elsevier, Amsterdam. Malashetty, M.S., Umavathi, J.C. and Leela, V., 2001. Magnetoconvective flow and heat transfer between vertical wavy wall and a parallel flat wall, Int. J. of Applied Mechanics and Engineering, Vol. 6, No. 2, pp. 437-456. Ostrich ...


    Directory of Open Access Journals (Sweden)

    S. V. Borshchevskyi


    Full Text Available The method of building the spill-concrete walls in mine holes of large diameter is analyzed. The variant of calculation of thickness of spill-concrete walls using such a method is offered. The recommendation on perfection of technology of timbering the mine holes of large diameter with a purpose of providing the durability and cost efficiency during the building of walls in vertical mines is proposed.

  20. Charged Domain Walls


    Campanelli, L.; Cea, P.; Fogli, G. L.; Tedesco, L.


    In this paper we investigate Charged Domain Walls (CDW's), topological defects that acquire surface charge density $Q$ induced by fermion states localized on the walls. The presence of an electric and magnetic field on the walls is also discussed. We find a relation in which the value of the surface charge density $Q$ is connected with the existence of such topological defects.

  1. Disruption Scenarios and their Effects on the Ignitor First Wall (United States)

    Bombarda, F.; Ramogida, G.; Roccella, M.; Lucca, F.; Marin, A.; Zanotelli, G. L.


    The 2D simulation of the reference plasma disruption in Ignitor (a fast current quench following a Vertical Displacement Event - VDE), has been performed using the MAXFEA code. The resulting excitation loads have been used in a detailed 3D model to evaluate the electromagnetic loads in the first wall and its supports. The model of the most loaded region of the first wall has been performed using a zooming procedure that allows the replacement of the out-of-model plasma, poloidal coils and passive structures with current filaments surrounding the modeled region. To identify the most stressed tiles under the effect of the electromagnetic loads due to the VDE, a preliminary structural analysis has been carried out using a simplified model. Then a more detailed model has been performed for these tiles, with the aim of evaluating the stress on the screw and the pre-load needed to avoid detachment between the tile and the tile-carrier. The thermal loads on the tiles are evaluated independently and the implications of possible other disruption scenarios are discussed.

  2. Growth of single-walled carbon nanotubes on a Co-Mo-MgO supported catalyst by the CVD of methane in a fixed bed reactor: Model setting and parameter estimation (United States)

    Izadi, Nosrat; Rashidi, Ali Morad; Horri, Bahman Amini; Mosoudi, Mohamad Reza; Bozorgzadeh, Hamid Reza; Zeraatkar, Ahmad


    In this work methane was decomposed to hydrogen and carbon to determine its kinetic behavior during reaction over a Co-Mo-MgO supported catalyst using the CVD (Chemical Vapor Deposition) technique. Decomposition of methane molecules was performed in a continuous fixed bed reactor to obtain data to simulate methane decomposition in a gas phase heterogeneous media. The products and reactants of reaction were analyzed by molecular sieve column followed by GC-analysis of the fractions to determine the amount of product converted or reactant consumed. The synthesis of single-walled carbon nanotubes was performed at atmospheric pressure, different temperatures and reactant concentrations. The experimental data analyzed to suggest the formula for calculation of the initial specific reaction rate of the carbon nanotubes synthesis, were fitted by several mathematical models derived from different mechanisms based on Longmuir-hinshelwood expression. The suggested mechanism according to dissociation adsorption of methane seems to explain the catalytic performance in the range of operating conditions studied. The apparent activation energy for the growth of SWNTs was estimated according to Arrhenius equation. The as grown SWNTs products were characterized by SEM, TEM and Raman spectroscopy after purification. The catalyst deactivation was found to be dependent on the time, reaction temperature and partial pressure of methane and indicated that the reaction of deactivation can be modeled by a simple apparent second order of reaction.

  3. Pd and Pt-Ru anode electrocatalysts supported on multi-walled carbon nanotubes and their use in passive and active direct alcohol fuel cells with an anion-exchange membrane (alcohol = methanol, ethanol, glycerol) (United States)

    Bambagioni, Valentina; Bianchini, Claudio; Marchionni, Andrea; Filippi, Jonathan; Vizza, Francesco; Teddy, Jacques; Serp, Philippe; Zhiani, Mohammad

    Palladium and platinum-ruthenium nanoparticles supported on multi-walled carbon nanotubes (MWCNT) are prepared by the impregnation-reduction procedure. The materials obtained, Pd/ MWCNT and Pt-Ru/ MWCNT, are characterized by TEM, ICP-AES and XRPD. Electrodes coated with Pd/ MWCNT are scrutinized for the oxidation of methanol, ethanol or glycerol in 2 M KOH solution in half cells. The catalyst is very active for the oxidation of all alcohols, with glycerol providing the best performance in terms of specific current density and ethanol showing the lowest onset potential. Membrane-electrode assemblies have been fabricated using Pd/ MWCNT anodes, commercial cathodes and anion-exchange membrane and evaluated in both single passive and active direct alcohol fuel cells fed with aqueous solutions of 10 wt.% methanol, 10 wt.% ethanol or 5 wt.% glycerol. Pd/ MWCNT exhibits unrivalled activity as anode electrocatalyst for alcohol oxidation. The analysis of the anode exhausts shows that ethanol is selectively oxidized to acetic acid, detected as acetate ion in the alkaline media of the reaction, while methanol yields carbonate and formate. A much wider product distribution, including glycolate, glycerate, tartronate, oxalate, formate and carbonate, is obtained from the oxidation of glycerol. The results obtained with Pt-Ru/ MWCNT anodes in acid media are largely inferior to those provided by Pd/ MWCNT electrodes in alkaline media.

  4. Assessment of Air Pollution Tolerance Index of some plants to develop vertical gardens near street canyons of a polluted tropical city. (United States)

    Pandey, Ashutosh Kumar; Pandey, Mayank; Tripathi, B D


    The aim of the present study was to examine Air Pollution Tolerance Index (APTI) of some climber plant species to develop vertical gardens in Varanasi city which has characteristics of tall building and narrow roads. This condition results in street canyon like structure and hinders the vertical dispersal of air pollutants. We have selected 24 climber plant species which are commonly found in of Varanasi city. Chosen plants can be easily grown either in planter boxes or directly in the ground, with a vertical support they can climb on walls to form green walls or vertical garden. Air Pollution Tolerance Index (APTI) of the selected plant species was calculated and plants with higher APTI are recommended for the development of Vertical garden. Highest APTI was noted for Ipomoea palmata (25.39) followed by Aristolochia elegans (23.28), Thunbergia grandiflora (23.14), Quisqualis indica (22.42), and Clerodendrum splendens (22.36). However, lowest APTI value (8.75) was recorded for the species Hemidesmus indicus. Moreover, the linear regression analysis has revealed a high positive correlation between APTI and ascorbic acid content (R2=0.8837) and positive correlation between APTI and Chlorophyll content (R2=0.6687). On the basis of higher APTI values (greater than 17), nine species of climber plants viz. I. palmata, T. grandiflora, C. splendens, A. elegans, Q. indica, Petria volubilis, Antigonon leptopus, Cryptolepis buchuanni and Tinospora cordifolia have been recommended to develop vertical greenery systems in a compact tropical city. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Natural convection air flow in vertical upright-angled triangular cavities under realistic thermal boundary conditions

    Directory of Open Access Journals (Sweden)

    Sieres Jaime


    Full Text Available This paper presents an analytical and numerical computation of laminar natural convection in a collection of vertical upright-angled triangular cavities filled with air. The vertical wall is heated with a uniform heat flux; the inclined wall is cooled with a uniform temperature; while the upper horizontal wall is assumed thermally insulated. The defining aperture angle φ is located at the lower vertex between the vertical and inclined walls. The finite element method is implemented to perform the computational analysis of the conservation equations for three aperture angles φ (= 15º, 30º and 45º and height-based modified Rayleigh numbers ranging from a low Ra = 0 (pure conduction to a high 109. Numerical results are reported for the velocity and temperature fields as well as the Nusselt numbers at the heated vertical wall. The numerical computations are also focused on the determination of the value of the maximum or critical temperature along the hot vertical wall and its dependence with the modified Rayleigh number and the aperture angle.

  6. Submicrometric 2D ratchet effect in magnetic domain wall motion

    Energy Technology Data Exchange (ETDEWEB)

    Castán-Guerrero, C., E-mail: [Instituto de Ciencia de Materiales de Aragón (ICMA), CSIC – Universidad de Zaragoza, E-50009 Zaragoza (Spain); Dpto. de Física de la Materia Condensada, Universidad de Zaragoza, E-50009 Zaragoza (Spain); Herrero-Albillos, J. [Fundación ARAID, E-50004 Zaragoza (Spain); Centro Universitario de la Defensa, E-50090 Zaragoza (Spain); Instituto de Ciencia de Materiales de Aragón (ICMA), CSIC – Universidad de Zaragoza, E-50009 Zaragoza (Spain); Sesé, J. [Instituto de Nanociencia de Aragón, Laboratorio de Microscopías Avanzadas, Universidad de Zaragoza, E-50018 Zaragoza (Spain); Dpto. de Física de la Materia Condensada, Universidad de Zaragoza, E-50009 Zaragoza (Spain); Bartolomé, J.; Bartolomé, F. [Instituto de Ciencia de Materiales de Aragón (ICMA), CSIC – Universidad de Zaragoza, E-50009 Zaragoza (Spain); Dpto. de Física de la Materia Condensada, Universidad de Zaragoza, E-50009 Zaragoza (Spain); Hierro-Rodriguez, A.; Valdés-Bango, F.; Martín, J.I.; Alameda, J.M. [Dpto. Física, Universidad de Oviedo, Asturias (Spain); CINN (CSIC – Universidad de Oviedo – Principado de Asturias), Asturias (Spain); García, L.M. [Instituto de Ciencia de Materiales de Aragón (ICMA), CSIC – Universidad de Zaragoza, E-50009 Zaragoza (Spain); Dpto. de Física de la Materia Condensada, Universidad de Zaragoza, E-50009 Zaragoza (Spain)


    Strips containing arrays of submicrometric triangular antidots with a 2D square periodicity have been fabricated by electron beam lithography. A clear ratchet effect of 180° domain wall motion under a varying applied field parallel to the walls has been observed. The direction is determined by the direction of the triangle vertices. In contrast, no ratchet effect is observed when the antidot array is constituted by symmetric rhomb-shaped antidots.

  7. A Physician's Perspective On Vertical Integration. (United States)

    Berenson, Robert A


    Vertical integration has been a central feature of health care delivery system change for more than two decades. Recent studies have demonstrated that vertically integrated health care systems raise prices and costs without observable improvements in quality, despite many theoretical reasons why cost control and improved quality might occur. Less well studied is how physicians view their newfound partnerships with hospitals. In this article I review literature findings and other observations on five aspects of vertical integration that affect physicians in their professional and personal lives: patients' access to physicians, physician compensation, autonomy versus system support, medical professionalism and culture, and lifestyle. I conclude that the movement toward physicians' alignment with and employment in vertically integrated systems seems inexorable but that policy should not promote such integration either intentionally or inadvertently. Instead, policy should address the flaws in current payment approaches that reward high prices and excessive service use-outcomes that vertical integration currently produces. Project HOPE—The People-to-People Health Foundation, Inc.

  8. GPS, su datum vertical.

    Directory of Open Access Journals (Sweden)

    Esteban Dörries


    Full Text Available La introducción de la metodología GPS en aplicaciones topográficas y geodésicas pone en notoria evidencia la clásica separación de sistemas de referencia en horizontal y vertical. Con GPS el posicionamiento es tridimensional, pero el concepto de altura difiere del clásico. Si se desea utilizar la información altimétrica debe contemplarse la ondulación del geoide.

  9. Abdominal wall fat pad biopsy (United States)

    Amyloidosis - abdominal wall fat pad biopsy; Abdominal wall biopsy; Biopsy - abdominal wall fat pad ... method of taking an abdominal wall fat pad biopsy . The health care provider cleans the skin on ...

  10. Green Walls Utilizing Internet of Things

    Directory of Open Access Journals (Sweden)

    Andrejs BONDAREVS


    Full Text Available A wireless sensor network was used to automatically control the life-support equipment of a green wall and to measure its influence on the air quality. Temperature, relative humidity, particulate matter, volatile organic compound and carbon dioxide were monitored during different tests. Green wall performance on improving the air quality and the influence of the air flow through the green wall on its performance were studied. The experimental results show that the green wall is effective to absorb particulate matter and volatile organic compound. The air flow through the green wall significantly increases the performance. The built-in fan increases the absorption rate of particulate matter by 8 times and that of formaldehyde by 3 times.

  11. Experimental study of ``laminar'' bubbly flows in a vertical pipe (United States)

    Kashinsky, O. N.; Timkin, L. S.; Cartellier, A.


    Measurement of bubbly two-phase flow parameters in a vertical pipe were performed. To keep the pipe Reynolds number below that for single-phase turbulent transition, a water-glycerin solution was used as the test liquid. Local void fraction and liquid velocity profiles along with the wall shear stress were measured by an electrochemical method. Experiments were made with bubbles of two different sizes. As the gas flow rate was increased, a gradual development of the liquid velocity profile from the parabolic Poiseuille flow to a flattened two-phase profile was observed. The evolution of the wall shear stress and of the velocity fluctuations were also quantified.

  12. Numerical simulation of water evaporation inside vertical circular tubes (United States)

    Ocłoń, Paweł; Nowak, Marzena; Majewski, Karol


    In this paper the results of simplified numerical analysis of water evaporation in vertical circular tubes are presented. The heat transfer in fluid domain (water or wet steam) and solid domain (tube wall) is analyzed. For the fluid domain the temperature field is calculated solving energy equation using the Control Volume Method and for the solid domain using the Finite Element Method. The heat transfer between fluid and solid domains is conjugated using the value of heat transfer coefficient from evaporating liquid to the tube wall. It is determined using the analytical Steiner-Taborek correlation. The pressure changes in fluid are computed using Friedel model.

  13. Bouldering: an alternative strategy to long-vertical climbing in root-climbing hortensias. (United States)

    Granados Mendoza, Carolina; Isnard, Sandrine; Charles-Dominique, Tristan; Van den Bulcke, Jan; Rowe, Nick P; Van Acker, Joris; Goetghebeur, Paul; Samain, Marie-Stéphanie


    In the Neotropics, the genus Hydrangea of the popular ornamental hortensia family is represented by climbing species that strongly cling to their support surface by means of adhesive roots closely positioned along specialized anchoring stems. These root-climbing hortensia species belong to the nearly exclusive American Hydrangea section Cornidia and generally are long lianescent climbers that mostly flower and fructify high in the host tree canopy. The Mexican species Hydrangea seemannii, however, encompasses not only long lianescent climbers of large vertical rock walls and coniferous trees, but also short 'shrub-like' climbers on small rounded boulders. To investigate growth form plasticity in root-climbing hortensia species, we tested the hypothesis that support variability (e.g. differences in size and shape) promotes plastic responses observable at the mechanical, structural and anatomical level. Stem bending properties, architectural axis categorization, tissue organization and wood density were compared between boulder and long-vertical tree-climbers of H. seemannii. For comparison, the mechanical patterns of a closely related, strictly long-vertical tree-climbing species were investigated. Hydrangea seemannii has fine-tuned morphological, mechanical and anatomical responses to support variability suggesting the presence of two alternative root-climbing strategies that are optimized for their particular environmental conditions. Our results suggest that variation of some stem anatomical traits provides a buffering effect that regulates the mechanical and hydraulic demands of two distinct plant architectures. The adaptive value of observed plastic responses and the importance of considering growth form plasticity in evolutionary and conservation studies are discussed. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  14. Biomechanics of gecko locomotion: the patterns of reaction forces on inverted, vertical and horizontal substrates. (United States)

    Wang, Zhouyi; Dai, Zhendong; Ji, Aihong; Ren, Lei; Xing, Qiang; Dai, Liming


    The excellent locomotion ability of geckos on various rough and/or inclined substrates has attracted scientists' attention for centuries. However, the moving ability of gecko-mimicking robots on various inclined surfaces still lags far behind that of geckos, mainly because our understanding of how geckos govern their locomotion is still very poor. To reveal the fundamental mechanism of gecko locomotion and also to facilitate the design of gecko-mimicking robots, we have measured the reaction forces (RFs) acting on each individual foot of moving geckos on inverted, vertical and horizontal substrates (i.e. ceiling, wall and floor), have associated the RFs with locomotion behaviors by using high-speed camera, and have presented the relationships of the force components with patterns of reaction forces (PRFs). Geckos generate different PRF on ceiling, wall and floor, that is, the PRF is determined by the angles between the direction of gravity and the substrate on which geckos move. On the ceiling, geckos produce reversed shear forces acting on the front and hind feet, which pull away from the body in both lateral and fore-aft directions. They use a very large supporting angle from 21° to 24° to reduce the forces acting on their legs and feet. On the floor, geckos lift their bodies using a supporting angle from 76° to 78°, which not only decreases the RFs but also improves their locomotion ability. On the wall, geckos generate a reliable self-locking attachment by using a supporting angle of 14.8°, which is only about half of the critical angle of detachment.

  15. Vertical Protocol Composition

    DEFF Research Database (Denmark)

    Groß, Thomas; Mödersheim, Sebastian Alexander


    composition, and it is truly commonplace in today’s communication with the diversity of VPNs and secure browser sessions. In fact, it is normal that we have several layers of secure channels: For instance, on top of a VPN-connection, a browser may establish another secure channel (possibly with a different...... end point). Even using the same protocol several times in such a stack of channels is not unusual: An application may very well establish another TLS channel over an established one. We call this selfcomposition. In fact, there is nothing that tells us that all these compositions are sound, i.......e., that the combination cannot introduce attacks that the individual protocols in isolation do not have. In this work, we prove a composability result in the symbolic model that allows for arbitrary vertical composition (including self-composition). It holds for protocols from any suite of channel and application...

  16. Vertical cavity laser

    DEFF Research Database (Denmark)


    The present invention provides a vertical cavity laser comprising a grating layer comprising an in-plane grating, the grating layer having a first side and having a second side opposite the first side and comprising a contiguous core grating region having a grating structure, wherein an index......, an index of refraction of the second low-index layer or air being less than 2; and a thickness of the cap layer and a thickness of the grating layer, and a pitch and a duty cycle of the grating structure are selected to obtain a resonance having a free-space resonance wavelength in the interval 300 nm to 3...... microns, the cap layer comprises an active region configured to generate or absorb photons at the free-space resonance wavelength by stimulated emission or absorption when a sufficient forward or reverse bias voltage is applied across the active region, a thickness of the first low-index layer is less...

  17. Experimental and numerical analysis of pre-compressed masonry walls in two-way-bending with second order effects

    Energy Technology Data Exchange (ETDEWEB)

    Milani, Gabriele, E-mail: [Department of Architecture, Built Environment and Construction Engineering (ABC), Politecnico diMilano, Piazza Leonardo da Vinci 32, 20133 Milan (Italy); Olivito, Renato S. [Dipartimento di Ingegneria Civile - Università della Calabria Via P Bucci 39 B - 87036 RENDE (CS) (Italy); Tralli, Antonio [Department of Engineering, University of Ferrara, Via Saragat 1, 44100 Ferrara (Italy)


    The buckling behavior of slender unreinforced masonry (URM) walls subjected to axial compression and out-of-plane lateral loads is investigated through a combined experimental and numerical homogenizedapproach. After a preliminary analysis performed on a unit cell meshed by means of elastic FEs and non-linear interfaces, macroscopic moment-curvature diagrams so obtained are implemented at a structural level, discretizing masonry by means of rigid triangular elements and non-linear interfaces. The non-linear incremental response of the structure is accounted for a specific quadratic programming routine. In parallel, a wide experimental campaign is conducted on walls in two way bending, with the double aim of both validating the numerical model and investigating the behavior of walls that may not be reduced to simple cantilevers or simply supported beams. Panels investigated are dry-joint in scale square walls simply supported at the base and on a vertical edge, exhibiting the classical Rondelet’s mechanism. The results obtained are compared with those provided by the numerical model.

  18. Direct Observation of Ultralow Vertical Emittance using a Vertical Undulator

    Energy Technology Data Exchange (ETDEWEB)

    Wootton, Kent


    In recent work, the first quantitative measurements of electron beam vertical emittance using a vertical undulator were presented, with particular emphasis given to ultralow vertical emittances [K. P. Wootton, et al., Phys. Rev. ST Accel. Beams, 17, 112802 (2014)]. Using this apparatus, a geometric vertical emittance of 0.9 ± 0.3 pm rad has been observed. A critical analysis is given of measurement approaches that were attempted, with particular emphasis on systematic and statistical uncertainties. The method used is explained, compared to other techniques and the applicability of these results to other scenarios discussed.

  19. Alignment of muscle precursor cells on the vertical edges of thick carbon nanotube films

    Energy Technology Data Exchange (ETDEWEB)

    Holt, Ian, E-mail: [Wolfson Centre for Inherited Neuromuscular Disease, RJAH Orthopaedic Hospital, Oswestry, Shropshire SY10 7AG (United Kingdom); Institute for Science and Technology in Medicine, Keele University, Keele, Staffordshire ST5 5BG (United Kingdom); Gestmann, Ingo, E-mail: [FEI Europe B.V., Achtseweg Noord 5, 5651 Eindhoven (Netherlands); Wright, Andrew C., E-mail: [Advanced Materials Research Laboratory, Glyndwr University, Plas Coch, Mold Rd, Wrexham LL11 2AW (United Kingdom)


    The development of scaffolds and templates is an essential aspect of tissue engineering. We show that thick (> 0.5 mm) vertically aligned carbon nanotube films, made by chemical vapour deposition, can be used as biocompatible substrates for the directional alignment of mouse muscle cells where the cells grow on the exposed sides of the films. Ultra high resolution scanning electron microscopy reveals that the films themselves consist mostly of small diameter (10 nm) multi-wall carbon nanotubes of wavy morphology with some single wall carbon nanotubes. Our findings show that for this alignment to occur the nanotubes must be in pristine condition. Mechanical wiping of the films to create directional alignment is detrimental to directional bioactivity. Larger areas for study have been formed from a composite of multiply stacked narrow strips of nanotubes wipe-transferred onto elastomer supports. These composite substrates appear to show a useful degree of alignment of the cells. Highlights: • Highly oriented muscle precursor cells grown on edges of carbon nanotube pads • Mechanical treatment of nanotube pads highly deleterious to cell growth on edges • Larger areas created from wipe-transfer of narrow strips of nanotubes onto elastomer supports • Very high resolution SEM reveals clues to aligned cell growth.

  20. The Revolutionary Vertical Lift Technology (RVLT) Project (United States)

    Yamauchi, Gloria K.


    The Revolutionary Vertical Lift Technology (RVLT) Project is one of six projects in the Advanced Air Vehicles Program (AAVP) of the NASA Aeronautics Research Mission Directorate. The overarching goal of the RVLT Project is to develop and validate tools, technologies, and concepts to overcome key barriers for vertical lift vehicles. The project vision is to enable the next generation of vertical lift vehicles with aggressive goals for efficiency, noise, and emissions, to expand current capabilities and develop new commercial markets. The RVLT Project invests in technologies that support conventional, non-conventional, and emerging vertical-lift aircraft in the very light to heavy vehicle classes. Research areas include acoustic, aeromechanics, drive systems, engines, icing, hybrid-electric systems, impact dynamics, experimental techniques, computational methods, and conceptual design. The project research is executed at NASA Ames, Glenn, and Langley Research Centers; the research extensively leverages partnerships with the US Army, the Federal Aviation Administration, industry, and academia. The primary facilities used by the project for testing of vertical-lift technologies include the 14- by 22-Ft Wind Tunnel, Icing Research Tunnel, National Full-Scale Aerodynamics Complex, 7- by 10-Ft Wind Tunnel, Rotor Test Cell, Landing and Impact Research facility, Compressor Test Facility, Drive System Test Facilities, Transonic Turbine Blade Cascade Facility, Vertical Motion Simulator, Mobile Acoustic Facility, Exterior Effects Synthesis and Simulation Lab, and the NASA Advanced Supercomputing Complex. To learn more about the RVLT Project, please stop by booth #1004 or visit their website at

  1. Retaining Walls Made of Precast Cylindrical Valuts

    Directory of Open Access Journals (Sweden)

    N. Ungureanu


    Full Text Available Retaining walls are large category of engineering structures of multiple uses, having an essential safety ensuring role. The structural systems are varied because the situations and requirements derived from both site conditions and other criteria are varied. The paper enlarges upon retaining walls systems that use an outstanding amount of precast units and multiple cylindrical vault type structural systems supported by abutments [1], [2]. The paper proposes extending the structural system to retaining walls and develops certain specific issues. Some considerations regarding structural design are made.

  2. Reaction Wood: Its Structure and Function: Lignification may generate the force active in restoring the trunks of leaning trees to the vertical. (United States)

    Scurfield, G


    The mechanism by which the stems of trees recover after being bent or tilted out of the vertical is considered. The mechanical consequences of the tendency for the main stem apex to reerect itself and grow vertically or to be replaced by a vertically growing lateral branch, and of the asymmetrical radial growth of displaced stems, are pointed out. The asymmetry usually develops on the upper side of a bent or tilted hardwood stem and on the under side of a softwood stem. Since such asymmetry can usually be accounted for on the basis of accentuated development of wood rather than bark, the question of the possible functional significance of the wood arises. Experiments are cited to demonstrate that the wood (reaction wood) is effective as a means for assisting displaced stems to recover, contracting longitudinally on the upper side of a hardwood stem and expanding on the under side of a softwood stem. Consideration is then given to the structure, differentiation, and chemical composition of the reaction wood formed by hardwoods and softwoods with a view to locating the force active in aiding recovery and determining its origin. The consequences of associating the support of a still-growing stem displaced from the vertical with the idiosyncracies of secondary wall formation of reaction wood cells, and the reerection of such a stem with lignification of these walls, are explored. On this basis, the hypothesis is advanced that the recovery force is located in the region of differentiating reaction wood cells undergoing lignification, the active force arising from the swelling of cell walls as a result of deposition in them of lignin. Objections to the hypothesis are mentioned.

  3. Vertical allometry: fact or fiction? (United States)

    Mahmood, Iftekhar; Boxenbaum, Harold


    In pharmacokinetics, vertical allometry is referred to the clearance of a drug when the predicted human clearance is substantially higher than the observed human clearance. Vertical allometry was initially reported for diazepam based on a 33-fold higher human predicted clearance than the observed human clearance. In recent years, it has been found that many other drugs besides diazepam, can be classified as drugs which exhibit vertical allometry. Over the years, many questions regarding vertical allometry have been raised. For example, (1) How to define and identify the vertical allometry? (2) How much difference should be between predicted and observed human clearance values before a drug could be declared 'a drug which follows vertical allometry'? (3) If somehow one can identify vertical allometry from animal data, how this information can be used for reasonably accurate prediction of clearance in humans? This report attempts to answer the aforementioned questions. The concept of vertical allometry at this time remains complex and obscure but with more extensive works one can have better understanding of 'vertical allometry'. Published by Elsevier Inc.

  4. Premixed flame propagation in vertical tubes

    CERN Document Server

    Kazakov, Kirill A


    Analytical treatment of premixed flame propagation in vertical tubes with smooth walls is given. Using the on-shell flame description, equations describing quasi-steady flame with a small but finite front thickness are obtained and solved numerically. It is found that near the limits of inflammability, solutions describing upward flame propagation come in pairs having close propagation speeds, and that the effect of gravity is to reverse the burnt gas velocity profile generated by the flame. On the basis of these results, a theory of partial flame propagation driven by the gravitational field is developed. A complete explanation is given of the intricate observed behavior of limit flames, including dependence of the inflammability range on the size of the combustion domain, the large distances of partial flame propagation, and the progression of flame extinction. The role of the finite front-thickness effects is discussed in detail. Also, various mechanisms governing flame acceleration in smooth tubes are ide...

  5. Supersymmetric domain walls

    NARCIS (Netherlands)

    Bergshoeff, Eric A.; Kleinschmidt, Axel; Riccioni, Fabio


    We classify the half-supersymmetric "domain walls," i.e., branes of codimension one, in toroidally compactified IIA/IIB string theory and show to which gauged supergravity theory each of these domain walls belong. We use as input the requirement of supersymmetric Wess-Zumino terms, the properties of

  6. Thin Wall Iron Castings

    Energy Technology Data Exchange (ETDEWEB)

    J.F. Cuttino; D.M. Stefanescu; T.S. Piwonka


    Results of an investigation made to develop methods of making iron castings having wall thicknesses as small as 2.5 mm in green sand molds are presented. It was found that thin wall ductile and compacted graphite iron castings can be made and have properties consistent with heavier castings. Green sand molding variables that affect casting dimensions were also identified.

  7. Timber frame walls

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan de Place; Brandt, Erik


    A ventilated cavity is usually considered good practice for removing moisture behind the cladding of timber framed walls. Timber frame walls with no cavity are a logical alternative as they are slimmer and less expensive to produce and besides the risk of a two-sided fire behind the cladding...

  8. International Divider Walls

    NARCIS (Netherlands)

    Kruis, A.; Sneller, A.C.W.(L.)


    The subject of this teaching case is the Enterprise Resource Planning (ERP) system implementation at International Divider Walls, the world market leader in design, production, and sales of divider walls. The implementation in one of the divisions of this multinational company had been successful,

  9. Cell wall heterogeneity in root development of Arabidopsis

    Directory of Open Access Journals (Sweden)

    Marc Somssich


    Full Text Available Plant cell walls provide stability and protection to plant cells. During growth and development the composition of cell walls changes, but provides enough strength to withstand the turgor of the cells. Hence, cell walls are highly flexible and diverse in nature. These characteristics are important during root growth, as plant roots consist of radial patterns of cells that have diverse functions and that are at different developmental stages along the growth axis. Young stem cell daughters undergo a series of rapid cell divisions, during which new cell walls are formed that are highly dynamic, and that support rapid anisotropic cell expansion. Once the cells have differentiated, the walls of specific cell types need to comply with and support different cell functions. For example, a newly formed root hair needs to be able to break through the surrounding soil, while endodermal cells modify their walls at distinct positions to form Casparian strips between them. Hence, the cell walls are modified and rebuilt while cells transit through different developmental stages. In addition, the cell walls of roots readjust to their environment to support growth and to maximize nutrient uptake. Many of these modifications are likely driven by different developmental and stress signalling pathways. However, our understanding of how such pathways affect cell wall modifications and what enzymes are involved remain largely unknown. In this review we aim to compile data linking cell wall content and re-modelling to developmental stages of root cells, and dissect how root cell walls respond to certain environmental changes.

  10. Yielding transition of Carbopol gel in a vertical pipe (United States)

    Liu, Yang; de Bruyn, John R.; John de Bruyn Team


    We have investigated the yielding transition of a simple yield-stress fluid (Carbopol 940) in a vertical pipe. The Carbopol gel was displaced by a Newtonian liquid injected at a constant, controlled rate at the bottom of the pipe. Rough- and smooth-walled pipes were used to study the effects of wall boundary conditions. The pressure in the Carbopol was measured by a pressure gauge fixed on the pipe wall, and the velocity profile in the Carbopol was measured by particle-image velocimetry (PIV). When the Newtonian liquid was injected, the rate of pressure increase was initially high, then decreased to a constant slow rate at later times. A time tc was defined by the intersection of straight lines fit to the pressure-time data at early and late times. In the rough pipe, the wall shear stress at tc is equal to the yield stress, suggesting that this time corresponds to yielding of the fluid. The velocity profiles were parabolic before yielding, and nearly a plug-like afterwards. In the smooth pipe, the pressure and velocity profiles appeared to show similar behavior to that in the rough pipe, but the wall shear stress at tc is substantially smaller than the yield stress and fluid motion was due to wall slip. NSERC.

  11. Adaptive wall technology for minimization of wall interferences in transonic wind tunnels (United States)

    Wolf, Stephen W. D.


    Modern experimental techniques to improve free air simulations in transonic wind tunnels by use of adaptive wall technology are reviewed. Considered are the significant advantages of adaptive wall testing techniques with respect to wall interferences, Reynolds number, tunnel drive power, and flow quality. The application of these testing techniques relies on making the test section boundaries adjustable and using a rapid wall adjustment procedure. A historical overview shows how the disjointed development of these testing techniques, since 1938, is closely linked to available computer support. An overview of Adaptive Wall Test Section (AWTS) designs shows a preference for use of relatively simple designs with solid adaptive walls in 2- and 3-D testing. Operational aspects of AWTS's are discussed with regard to production type operation where adaptive wall adjustments need to be quick. Both 2- and 3-D data are presented to illustrate the quality of AWTS data over the transonic speed range. Adaptive wall technology is available for general use in 2-D testing, even in cryogenic wind tunnels. In 3-D testing, more refinement of the adaptive wall testing techniques is required before more widespread use can be planned.

  12. Evaluation of Aesthetic Function and Thermal Modification of Vertical Greenery at Bogor City, Indonesia (United States)

    Sulistyantara, B.; Sesara, R.


    Bogor city currently develops vertical greenery due to counter the decreasing of green space quantity. Vertical greenery is a planting method using vertical structure similar to retaining walls. There are some benefits of vertical greenery, such as providing aesthetics value of the landscape, to protect from the heat, to reduce noise, and to reduce pollution. The purpose of this study were to identify thermal modification by vertical greenery in Bogor city, to assess the aesthetics value from vertical greenery, and to provide a recommendation in attempt to manage and improve the quality of vertical greenery in Bogor city. The study was conducted using Scenic Beauty Estimation method, and was done by providing questionnaires to the respondents in order to assess the aesthetics value of vertical greenery. Infrared thermometer was also used to measure the surface’s temperature to evaluate thermal modification function of the vertical greenery. The result of study proved that vertical greenery in the Bogor city has considerably good aesthetic. It also showed that there is a decreasing in surface temperature of the vertical greenery structure.

  13. (Hydroxyproline-rich glycoproteins of the plant cell wall)

    Energy Technology Data Exchange (ETDEWEB)

    Varner, J.E.


    We are studying the chemistry and architecture of plant cells walls, the extracellular matrices that taken together shape the plant and provide mechanical support for the plant. Cell walls are dynamic structures that regulate, or are the site of, many physiological processes, in addition to being the cells' first line of defense against invading pathogens. In the past year we have examined the role of the cell wall enzyme ascorbic acid oxidase as related to the structure of the wall and its possible interactions with hydroxyproline-rich glycoproteins of the wall.

  14. Buoyancy induced Couette-Poiseuille flow in a vertical microchannel (United States)

    Narahari, M.


    The fully developed buoyancy-induced (natural convective) Couette-Poiseuille flow in a vertical microchannel is investigated with the velocity slip and temperature jump boundary conditions. Closed form analytical solutions for the velocity and temperature fields are obtained. The effects of the fluid-wall interaction parameter, wall-ambient temperature difference ratio, Knudsen number, mixed convection parameter, and the dimensionless pressure gradient on the velocity, temperature, volume flow rate, heat flux between the plates and the Nusselt number have been discussed in detail through graphs. The outcomes of the investigation indicate that the volume flow rate increases with increasing values of mixed convection parameter, wall-ambient temperature difference ratio, and Knudsen number.

  15. Progress and Prospects in Developing Marine Vertical Datum

    Directory of Open Access Journals (Sweden)

    ZHOU Xinghua


    Full Text Available Marine vertical datum system construction is the basic work of marine surveying. In the 2009-2012, China has preliminarily constructed the transformation and unification of different height/depth datum model in the China Sea of 80 nautical mile. In recent years, this model has been extended to the South China Sea, the western Pacific and the eastern Indian Ocean, and then a seamless vertical datum model in the south and north pole area to the whole world gradually will be constructed in the near future, this is the foundation of supporting the digital ocean construction in China. This paper mainly discusses the research status of marine vertical datum construction which had been carried out in major coastal countries or regions, analyzes the main work and approaches and key technologies in the process of the marine vertical datum system building, and then expounds the achievements and existing problems in the practice of our country marine vertical datum building.

  16. Protected Vertices in Motzkin trees


    Van Duzer, Anthony


    In this paper we find recurrence relations for the asymptotic probability a vertex is $k$ protected in all Motzkin trees. We use a similar technique to calculate the probabilities for balanced vertices of rank $k$. From this we calculate upper and lower bounds for the probability a vertex is balanced and upper and lower bounds for the expected rank of balanced vertices.

  17. Timber frame walls

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan de Place; Brandt, Erik


    A ventilated cavity is usually considered good practice for removing moisture behind the cladding of timber framed walls. Timber frame walls with no cavity are a logical alternative as they are slimmer and less expensive to produce and besides the risk of a two-sided fire behind the cladding...... is reduced. To investigate the possibilities, full-size wall elements with wooden cladding and different cavity design, type of cladding and type of wind barrier were exposed to natural climate on the outside and to a humid indoor climate on the inside. During the exposure period parts of the vapour barrier...

  18. Long-term global response analysis of a vertical axis wind turbine supported on a semi-submersible floating platform: Comparison between operating and non-operating wind turbine load cases

    DEFF Research Database (Denmark)

    Collu, Maurizio; Manuel, Lance; Borg, Michael


    This study continues [1] the examination of the long-term global response of a floating vertical axis wind turbine (VAWT) situated off the Portuguese coast in the Atlantic Ocean. The VAWT, which consists of a 5-MW 3-bladed H-type rotor developed as part of the EU-FP7 H2OCEAN project, is assumed...... to be mounted on the OC4 semi-submersible floating platform. Adding a non-operational load case (wind speed 35m/s), the sea states identified are used to carry out coupled dynamics simulations using the FloVAWT design tool, for which an improved wave elevation and relative force/moment time signals approach...... is adopted, as well as also taking into account the drag generated by the wind turbine tower. Short-term turbine load and platform motion statistics are established for individual sea states that are analysed. The long-term reliability yields estimates of 50-year loads and platform motions that takes...

  19. Analysis of vertical stability limits and vertical displacement event behavior on NSTX-U (United States)

    Boyer, Mark; Battaglia, Devon; Gerhardt, Stefan; Menard, Jonathan; Mueller, Dennis; Myers, Clayton; Sabbagh, Steven; Smith, David


    The National Spherical Torus Experiment Upgrade (NSTX-U) completed its first run campaign in 2016, including commissioning a larger center-stack and three new tangentially aimed neutral beam sources. NSTX-U operates at increased aspect ratio due to the larger center-stack, making vertical stabilization more challenging. Since ST performance is improved at high elongation, improvements to the vertical control system were made, including use of multiple up-down-symmetric flux loop pairs for real-time estimation, and filtering to remove noise. Similar operating limits to those on NSTX (in terms of elongation and internal inductance) were achieved, now at higher aspect ratio. To better understand the observed limits and project to future operating points, a database of vertical displacement events and vertical oscillations observed during the plasma current ramp-up on NSTX/NSTX-U has been generated. Shots were clustered based on the characteristics of the VDEs/oscillations, and the plasma parameter regimes associated with the classes of behavior were studied. Results provide guidance for scenario development during ramp-up to avoid large oscillations at the time of diverting, and provide the means to assess stability of target scenarios for the next campaign. Results will also guide plans for improvements to the vertical control system. Work supported by U.S. D.O.E. Contract No. DE-AC02-09CH11466.

  20. Confinement effects in shock/turbulent-boundary-layer interaction through wall-modeled LES (United States)

    Bermejo-Moreno, Ivan; Campo, Laura; Larsson, Johan; Bodart, Julien; Helmer, David; Eaton, John


    Wall-modeled large-eddy simulations (WMLES) are used to investigate three-dimensional effects imposed by lateral confinement on the interaction of oblique shock waves impinging on turbulent boundary layers (TBLs) developed along the walls of a nearly-square duct. A constant Mach number, M = 2 . 05 , of the incoming air stream is considered, with a Reynolds number based on the incoming turbulent boundary layer momentum thickness Reθ 14 , 000 . The strength of the impinging shock is varied by increasing the height of a compression wedge located at a constant streamwise location that spans the top wall of the duct at a 20° angle. Simulation results are first validated with particle image velocimetry (PIV) experimental data obtained at several vertical planes. Emphasis is placed on the study of the instantaneous and time-averaged structure of the flow for the stronger-interaction case, which shows mean flow reversal. By performing additional spanwise-periodic simulations, it is found that the structure and location of the shock system and separation bubble are significantly modified by the lateral confinement. Low-frequency unsteadiness and downstream evolution of corner flows are also investigated. Financial support from the United States Department of Energy under the PSAAP program is gratefully acknowledged.

  1. Dynamic Response of Wall Backfill Retaining System

    Directory of Open Access Journals (Sweden)

    Sreenivas Alampalli


    Full Text Available An in situ full-scale test is conducted to measure the dynamic response of a long cantilever wall that retains backfill soil. The recorded modal parameters of this retaining wall exhibited significant similarity to those of a clamped cantilever plate (rather than those of a cantilever beam or plane-strain analysis. Such a three-dimensional (3-D response pattern is not accounted for by current analysis procedures. A simple 3-D finite element model is employed to further analyze the observed resonant configurations. The results indicate that such configurations play an important role in the seismic response of wall backfill soil systems of variable height, such as wing walls supporting highway approach ramps.

  2. Effects of Moving Side Walls on Confined Granular Packings

    Directory of Open Access Journals (Sweden)

    Ram Chand


    Full Text Available Granular materials have numerous industrial and geophysical applications. However, many phenomenon exhibited by granular media are not yet fully explained. Nowadays simulation has emerged as an important tool to investigate the complex properties exhibited by granular media. The influence of side walls movement of a granular column is investigated by discrete element, molecular dynamics simulations. The evolution of stress profile and deflection of vertical stresses is due to different bead sizes, coefficient of friction between grains and confining wall is investigated by using large-scale discrete element MD simulations in 3D. In such a configuration, it is found that apparent mass systemically increases with the increase in diameter of granules. As soon as the wall stops moving, the column attains equilibrium. The stress profiles are in good agreement with the Janssen form for high friction coefficient, while some deviations remain for smaller values of friction coefficient. The wall movement augments the number of particle-wall and particle-particle forces at the Coulomb criterion. The results indicate the variation in shielding of vertical stresses in granular column; it can be attributed to the fiction between the beads and the confining walls of the container.

  3. Vertical Footbridge Vibrations: The Response Spectrum Methodology

    DEFF Research Database (Denmark)

    Georgakis, Christos; Ingólfsson, Einar Thór


    In this paper, a novel, accurate and readily codifiable methodology for the prediction of vertical footbridge response is presented. The methodology is based on the well-established response spectrum approach used in the majority of the world’s current seismic design codes of practice. The concept...... of a universally applicable reference response spectrum is introduced, from which the pedestrian-induced vertical response of any footbridge may be determined, based on a defined “event” and the probability of occurrence of that event. A series of Monte Carlo simulations are undertaken for the development...... of a reference response spectrum. The simulations use known statistical data for pedestrian and population walking characteristics to generate loads for a 50m long simply-supported bridge, with a fixed level of damping and a mean pedestrian flow rate of 1 pedestrian / sec. The response obtained from...

  4. Anterior vaginal wall repair (United States)

    ... may have you: Learn pelvic floor muscle exercises ( Kegel exercises ) Use estrogen cream in your vagina Try ... repair; Urinary incontinence - vaginal wall repair Patient Instructions Kegel exercises - self-care Self catheterization - female Suprapubic catheter ...

  5. Advanced walling systems

    CSIR Research Space (South Africa)

    De Villiers, A


    Full Text Available The question addressed by this chapter is: How should advanced walling systems be planned, designed, built, refurbished, and end their useful lives, to classify as smart, sustainable, green or eco-building environments?...

  6. Evaluation of drag forcing models for vertical axis wind turbine farms (United States)

    Pierce, Brian; Moin, Parviz; Dabiri, John


    Vertical axis wind turbines (VAWTs) have the potential to produce more power per unit area than horizontal axis wind turbines (HAWTs) in a wind farm setting (Kinzel et al. J. Turb. [2012]), but further understanding of the flow physics is required to design such farms. In this study we will model a large wind farm of VAWTs as an array of 100 circular cylinders which will allow a comparison with a laboratory experiment (Craig et al. DFD 2013). The geometric complexity and high Reynolds numbers necessitate phenomenological modeling of the interaction of the turbine with the fluid, which is done through point drag models similar to those found in canopy flow simulations (e.g. Dupont et al. J. Fluid Mech. [2010]). We will present a detailed study of the point drag model performance for flow over one cylinder, providing an evaluation of the model's fidelity as it relates to quantities of interest for the VAWT farm. Next we will present results for flow through the cylinder array, emphasizing validation of the model and insight into VAWT wind farm dynamics. We will also discuss the effect of wall modeling on the calculations, as the Reynolds number of the problem requires the application of wall modeling of the turbulent boundary layer above the ground to keep the cost manageable. Brian Pierce acknowledges support from the Stanford Graduate Fellowship.

  7. Direct numerical simulation of turbulent core-annular flow in a vertical pipe (United States)

    Kim, Kiyoung; Choi, Haecheon


    The core-annular flow has been considered as a useful tool to effectively transport highly viscous oil by having lower viscous fluid such as water near the pipe surface. There have been several studies to investigate turbulent core-annular flows but most of them have been conducted experimentally. We solve the three-dimensional Navier-Stokes equations in a cylindrical coordinate and use the level-set method for interface tracking between two fluids (oil and water). A few different flow parameters such as the superficial velocity of fluids and mean pressure gradient are considered in a vertical pipe. The results show that the oil core region is nearly a plug flow and the water region experiences high shear rates, which generate turbulence structures different from those of single phase flow. The interface wave suppresses the near-wall coherent structures but produces complex fluid motions caused by its interaction with the wall. The phenomenon of maximum drag reduction and the effect of water turbulence on total drag will be discussed at the presentation. We gratefully acknowledge financial support from the NRF Programs (No. 2012M2A8A4055647), Mest, Korea.

  8. Analysis of Contribution of Vertical Gardens to Urban Sustainability: The Case Study of Antalya City, Turkey


    KAYNAKÇI ELİNÇ, Zuhal; KAYA, Latif Gürkan; ELİNÇ, Hakan


    Vertical garden's studies, having been defined a new perspective to the modern construction culture, has been application of the garden to a building facade or to a wall surface as a notion. Application of plants to the vertical surfaces make contributions to urban ecology due to its functions such as aesthetical and visual values as well as protection of the buildings, habilitating the climate effects for human beings, enhancing the environmental aspects and reducing certain ambient pro...

  9. Novel titanium constructs for chest wall reconstruction in children. (United States)

    Stephenson, Jacob T; Song, Kit; Avansino, Jeffrey R; Mesher, Andrew; Waldhausen, John H T


    We have previously reported the use of the vertical expandable prosthetic titanium rib (VEPTR) for treatment of thoracic dystrophy. This report describes our experience with this device and other novel titanium constructs for chest wall reconstruction. This is a retrospective chart review of all children and adolescents undergoing chest wall reconstruction with titanium constructs between December 2005 and May 2010. Six patients have undergone chest wall reconstruction with VEPTR or other titanium constructs. Four had chest wall resection for primary malignancy, 1 had metastatic chest wall tumor resection, and 1 had congenital chest wall deformity. There were no immediate complications, and all patients have exhibited excellent respiratory function with no scoliosis. Chest wall reconstruction after tumor resection or for primary chest wall deformities can be effectively accomplished with VEPTR and other customized titanium constructs. Goals should be durable protection of intrathoracic organs and preservation of thoracic volume and function throughout growth. Careful preoperative evaluation and patient-specific planning are important aspects of successful reconstruction. Copyright © 2011 Elsevier Inc. All rights reserved.

  10. Theoretical axial wall angulation for rotational resistance form in an experimental-fixed partial denture. (United States)

    Bowley, John Francis; Kaye, Elizabeth Krall; Garcia, Raul Isidro


    The aim of this study was to determine the influence of long base lengths of a fixed partial denture (FPD) to rotational resistance with variation of vertical wall angulation. Trigonometric calculations were done to determine the maximum wall angle needed to resist rotational displacement of an experimental-FPD model in 2-dimensional plane. The maximum wall angle calculation determines the greatest taper that resists rotation. Two different axes of rotation were used to test this model with five vertical abutment heights of 3-, 3.5-, 4-, 4.5-, and 5-mm. The two rotational axes were located on the mesial-side of the anterior abutment and the distal-side of the posterior abutment. Rotation of the FPD around the anterior axis was counter-clockwise, Posterior-Anterior (P-A) and clockwise, Anterior-Posterior (A-P) around the distal axis in the sagittal plane. Low levels of vertical wall taper, ≤ 10-degrees, were needed to resist rotational displacement in all wall height categories; 2-to-6-degrees is generally considered ideal, with 7-to-10-degrees as favorable to the long axis of the abutment. Rotation around both axes demonstrated that two axial walls of the FPD resisted rotational displacement in each direction. In addition, uneven abutment height combinations required the lowest wall angulations to achieve resistance in this study. The vertical height and angulation of FPD abutments, two rotational axes, and the long base lengths all play a role in FPD resistance form.

  11. Turbine airfoil having near-wall cooling insert

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Jr., Nicholas F.; Wiebe, David J.


    A turbine airfoil is provided with at least one insert positioned in a cavity in an airfoil interior. The insert extends along a span-wise extent of the turbine airfoil and includes first and second opposite faces. A first near-wall cooling channel is defined between the first face and a pressure sidewall of an airfoil outer wall. A second near-wall cooling channel is defined between the second face and a suction sidewall of the airfoil outer wall. The insert is configured to occupy an inactive volume in the airfoil interior so as to displace a coolant flow in the cavity toward the first and second near-wall cooling channels. A locating feature engages the insert with the outer wall for supporting the insert in position. The locating feature is configured to control flow of the coolant through the first or second near-wall cooling channel.


    Directory of Open Access Journals (Sweden)

    Rahmadya Putra Nugraha


    Full Text Available Modern society nowadays technological advances at first create efficiency in human life. Further development of the technology thus drown human in a routine and automation of work created. The State is to be one of the causes of man separated from fellow or the outside world and eventually experiencing alienation. The movie as a mass media function to obtain the movie and entertainment can be informative or educative function is contained, even persuasive. The purpose of this research was conducted to find out the alienation in the movie Wall E. The concepts used to analyze the movie Wall E this is communication, movie, and alienation. The concept of alienation of human alienation from covering its own products of human alienation from its activities, the human alienation from nature of his humanity and human alienation from each other. Paradigm used is a critical paradigm with type a descriptive research with qualitative approach. The method used is the analysis of semiotics Roland Barthes to interpretation the scope of social alienation and fellow humans in the movie.This writing research results found that alienation of humans with other humans influenced the development of the technology and how the human it self represented of technology, not from our fellow human beings. Masyarakat modern saat ini kemajuan teknologi pada awalnya membuat efisiensi dalam kehidupan manusia. Perkembangan selanjutnya teknologi justru menenggelamkan manusia dalam suatu rutinitas dan otomatisasi kerja yang diciptakan. Keadaan itulah yang menjadi salah satu penyebab manusia terpisah dari sesama atau dunia luar dan akhirnya mengalami keterasingan. Film sebagai media massa berfungsi untuk memperoleh hiburan dan dalam film dapat terkandung fungsi informatif maupun edukatif, bahkan persuasif. Tujuan Penelitian ini dilakukan untuk mengetahui Keterasingan dalam film Wall E. Konsep-konsep yang digunakan untuk menganalisis film Wall E ini adalah komunikasi, film, dan

  13. Trade Liberalisation and Vertical Integration

    DEFF Research Database (Denmark)

    Bache, Peter Arendorf; Laugesen, Anders Rosenstand

    producers face decisions on exporting, vertical integration of intermediate-input production, and whether the intermediate-input production should be offshored to a low-wage country. We find that the fractions of final-good producers that pursue either vertical integration, offshoring, or exporting are all......We build a three-country model of international trade in final goods and intermediate inputs and study the relation between four different types of trade liberalisation and vertical integration. Firms are heterogeneous with respect to both productivity and factor (headquarter) intensity. Final-good...... increasing when intermediate-input trade or final-goods trade is liberalised. Finally, we provide guidance for testing the open-economy property rights theory of the firm using firm-level data and surprisingly show that the relationship between factor (headquarter) intensity and the likelihood of vertical...

  14. Horizontal and Vertical Line Designs. (United States)

    Johns, Pat


    Presents an art lesson in which students learn about the artist Piet Mondrian and create their own abstract artworks. Focuses on geometric shapes using horizontal and vertical lines. Includes background information about the artist. (CMK)

  15. Vertical axis wind turbine airfoil (United States)

    Krivcov, Vladimir; Krivospitski, Vladimir; Maksimov, Vasili; Halstead, Richard; Grahov, Jurij Vasiljevich


    A vertical axis wind turbine airfoil is described. The wind turbine airfoil can include a leading edge, a trailing edge, an upper curved surface, a lower curved surface, and a centerline running between the upper surface and the lower surface and from the leading edge to the trailing edge. The airfoil can be configured so that the distance between the centerline and the upper surface is the same as the distance between the centerline and the lower surface at all points along the length of the airfoil. A plurality of such airfoils can be included in a vertical axis wind turbine. These airfoils can be vertically disposed and can rotate about a vertical axis.

  16. Vertical designs and agriculture joined for food production in the modules for urban vertical gardens.

    Directory of Open Access Journals (Sweden)

    Fritz Hammerling Navas Navarro


    Full Text Available Modules for Vertical Urban Gardens (MHUG are a hybrid of vertical gardens and urban agriculture. Vertical gardens have been recognized for the past 2500 years, mainly in the form of the Hanging Gardens of Babylon, while urban agriculture is being practiced today by more than 700 million people worldwide. The benefits that MHUV offers are multiple, but perhaps the most significant is the consumption of foods free of chemicals, free of GMO’s, irrigated with potable water, and that are 100% organic. It is presented a “culinary and medicinal module” that can be implemented in the kitchen area, on roofs, terraces, balconies or patios, where species such as thyme, mint, peppermint, parsley, lemon balm and rosemary can be at hand when preparing dishes. The module consists of three plastic baskets that are recyclable and resistant to decay. Each basket has four rows with space for fourteen seedlings. The baskets are first lined on the interior with a black geotextile, and then are covered with a mesh (polisombra which helps support the substrate and seedlings. Each basket rests on a structure made of recycled wood (from pallets or crates that both holds the basket vertically and serves as a rain cover. The cages measure 0.33m by 0.55m by 0.14m. Each module comes with hosing and connectors for a drip irrigation system, and an instructional manual. The modules demonstrate the benefits of urban agriculture combined with the beauty and modality of vertical gardens, leading to useful applications for food production and decoration in the spaces where vertical urban gardens are possible.

  17. Backward integration, forward integration, and vertical foreclosure


    Spiegel, Yossi


    I show that partial vertical integration may either alleviates or exacerbate the concern for vertical foreclosure relative to full vertical integration and I examine its implications for consumer welfare.

  18. Experiments on rapidly-sheared wall turbulence (United States)

    Diwan, Sourabh; Morrison, Jonathan


    The use of linear theories in wall turbulence dates back to Townsend (1976, Cambridge University Press) who extensively used Rapid Distortion Theory (RDT) for understanding the structure of near-wall turbulence. Various other linear tools have been used in more recent investigations. The present study is an attempt to further explore this aspect and is in part motivated by the recent numerical work of Sharma et al. (Phys. Fluids 23, 2011) that highlighted the possible role of linear mechanisms in wall turbulence. Our experimental arrangement involves passing a grid-generated turbulent flow over a flat plate mounted downstream of the grid in a wind tunnel. The grid turbulence is subjected to large rates of shear strain by the wall layer close to the leading edge of the plate and as a result, over a certain region in its vicinity, the approximations of the RDT can be expected to be approximately satisfied. We present detailed single-point and planar velocity measurements, and pressure measurements using surface-mounted pressure transducers, the aim being to establish a turbulent wall layer in which linear processes are dominant. Such a flow can be used to evaluate the ideas relating to linear theories of Townsend and Landahl, among others. We also present the structural changes that take place as the rapidly-sheared wall layer evolves towards a more conventional boundary layer further downstream. We acknowledge financial support from EPSRC under Grant No. EP/I037938.

  19. Improvement of vertical stabilization on KSTAR (United States)

    Mueller, D.; Bak, J. G.; Boyer, M. D.; Eideitis, N.; Hahn, S. H.; Humphreys, D. A.; Kim, H. S.; Jeon, Y. M.; Lanctot, M.; Walker, M. L.


    The successful control of strongly shaped plasmas on the Korea Superconducting Tokamak Advanced Research (KSTAR) device requires active feedback of fast motion of the plasma vertical position by the use of internal normal conducting coils (IVC). This has required new electronics to supply relative flux loop differences, for zp, and voltage loop differences, for dzp/dt, as well as a novel technique (Zfast) to use a high-pass filter, typically 1 Hz, on the error in the signal in the feedback loop. Use of Zfast avoids the potential contention encountered when the internal coil attempts to perform control of the plasma shape which should be controlled by the slower and more powerful superconducting coils. A common problem of this contention is saturation of the IVC and loss of fast vertical control. This is eliminated by proper use of the Zfast. A Ziegler-Nichols relay feedback system was used to fine tune the required feedback gains. The selection of the magnetic sensors, filter time constants, control gains and of the Zfast control strategy which allowed vertically stable operation at a plasma elongation, kappa. of up to 2.16 at li = 1.15 and Betap = 2.4 will be discussed which is beyond the design reference of KSTAR of kappa = 2.0 at li = 1.2 and Betap = 1.9. Work Supported by U.S.D.O.E. Contract No. DE-AC02-09CH11466 and DE-SC0010685 and the KSTAR project.

  20. Electroweak bubble wall speed limit (United States)

    Bödeker, Dietrich; Moore, Guy D.


    In extensions of the Standard Model with extra scalars, the electroweak phase transition can be very strong, and the bubble walls can be highly relativistic. We revisit our previous argument that electroweak bubble walls can "run away," that is, achieve extreme ultrarelativistic velocities γ ~ 1014. We show that, when particles cross the bubble wall, they can emit transition radiation. Wall-frame soft processes, though suppressed by a power of the coupling α, have a significance enhanced by the γ-factor of the wall, limiting wall velocities to γ ~ 1/α. Though the bubble walls can move at almost the speed of light, they carry an infinitesimal share of the plasma's energy.

  1. Effect of plastic soil on a retaining wall subjected to surcharge loading

    Directory of Open Access Journals (Sweden)

    Al-Juari Khawla


    Full Text Available The seasonal variation and climatic changes play a significant role that affects the stresses exerted on a retaining wall, and the state of stresses in the soil mass behind the wall especially for highly expansive soil. These stresses resulted in the wall moving either away or towards the soil. In this study, a laboratory physical model of the retaining wall formed of a box having (950×900×600 mm dimensions with one side representing the wall being developed. After the soil being laid out in the box in specified layers, specified conditions of saturation and normal stresses were applied. The wall is allowed to move horizontally in several distances (0.1, 0.2, 0.3, 0.6, 0.8, 1.0 , 2.0, 3.0 and 4.0 mm, and the stresses being measured, then the vertical loading was released. The main measured variables during the tests are; the active and passive earth pressures, vertical movement of the soil, total suction and time. Results showed that the lateral earth pressure along the depth of the wall largely decreased when wall moved away from the soil. Total suction was slightly affected during wall’s movement. At unloading stage, the lateral earth pressure decreased at the upper half of wall height, but increased at the other wall part. Total suction was increased at all depths during this stage.

  2. Vertical Dynamic Stiffness of Offshore Foundations

    DEFF Research Database (Denmark)

    Latini, Chiara; Cisternino, Michele; Zania, Varvara


    Nowadays, pile and suction caisson foundations are widely used to support offshore structures which are subjected to vertical dynamic loads. The dynamic soil-structure interaction of floating foundations (foundations embedded in a soil layer whose height is greater than the foundation length......) is investigated by numerical analyses of representative finite element models. The 3D numerical model is compared and validated with existing analytical solutions. A parametric study is carried out analyzing the effect of the slenderness ratio Hp/d and the height and the stiffness of the soil layer on the dynamic...

  3. Wall Vegetation Characteristics of Urban and Sub-Urban Areas

    National Research Council Canada - National Science Library

    Emrah Yalcinalp; Alperen Meral


    ... on them. Therefore, creating gardens on vertical surfaces of urban areas has recently been very important to supporting sustainability because these surfaces are still found to be commercially useless...

  4. Dynamic optimal foraging theory explains vertical migrations of bigeye tuna

    DEFF Research Database (Denmark)

    Thygesen, Uffe Høgsbro; Sommer, Lene; Evans, Karen


    Bigeye tuna are known for remarkable daytime vertical migrations between deep water, where food is abundant but the water is cold, and the surface, where water is warm but food is relatively scarce. Here we investigate if these dive patterns can be explained by dynamic optimal foraging theory......, where the tuna maximizes its energy harvest rate. We assume that foraging efficiency increases with body temperature, so that the vertical migrations are thermoregulatory. The tuna's state is characterized by its mean body temperature and depth, and we solve the optimization problem numerically using...... dynamic programming. With little calibration of model parameters, our results are consistent with observed data on vertical movement: we find that small tuna should display constant-depth strategies while large tuna should display vertical migrations. The analysis supports the hypothesis that the tuna...

  5. A Method for Modeling of Floating Vertical Axis Wind Turbine

    DEFF Research Database (Denmark)

    Wang, Kai; Hansen, Martin Otto Laver; Moan, Torgeir


    It is of interest to investigate the potential advantages of floating vertical axis wind turbine (FVAWT) due to its economical installation and maintenance. A novel 5MW vertical axis wind turbine concept with a Darrieus rotor mounted on a semi-submersible support structure is proposed in this paper....... In order to assess the technical and economic feasibility of this novel concept, a comprehensive simulation tool for modeling of the floating vertical axis wind turbine is needed. This work presents the development of a coupled method for modeling of the dynamics of a floating vertical axis wind turbine....... This integrated dynamic model takes into account the wind inflow, aerodynamics, hydrodynamics, structural dynamics (wind turbine, floating platform and the mooring lines) and a generator control. This approach calculates dynamic equilibrium at each time step and takes account of the interaction between the rotor...

  6. Vertical saccades in dyslexic children. (United States)

    Tiadi, Aimé; Seassau, Magali; Bui-Quoc, Emmanuel; Gerard, Christophe-Loïc; Bucci, Maria Pia


    Vertical saccades have never been studied in dyslexic children. We examined vertical visually guided saccades in fifty-six dyslexic children (mean age: 10.5±2.56 years old) and fifty-six age matched non dyslexic children (mean age: 10.3±1.74 years old). Binocular eye movements were recorded using an infrared video-oculography system (mobileEBT®, e(ye)BRAIN). Dyslexic children showed significantly longer latency than the non dyslexic group, also the occurrence of anticipatory and express saccades was more important in dyslexic than in non dyslexic children. The gain and the mean velocity values were significantly smaller in dyslexic than in non dyslexic children. Finally, the up-down asymmetry reported in normal population for the gain and the velocity of vertical saccades was observed in dyslexic children and interestingly, dyslexic children also reported an up-down asymmetry for the mean latency. Taken together all these findings suggested impairment in cortical areas responsible of vertical saccades performance and also at peripheral level of the extra-ocular oblique muscles; moreover, a visuo-attentionnal bias could explain the up-down asymmetry reported for the vertical saccade triggering. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. First Wall Design for the IGNITOR Machine* (United States)

    Cucchiaro, A.; Frosi, P.; Pizzuto, A.; Maddaluno, G.; Ramogida, G.; Bianchi, A.; Parodi, B.; Lucca, F.; Marin, A.; Coppi, B.


    A detailed 3D finite element model has been developed in order to evaluate the electromagnetic loads on the (mechanical) carriers of the tiles that constitute the First Wall of Ignitor during a reference Vertical Disruption Event. A thermo- structural analisys of the most stressed tile carrier with a cycled load has been completed. The study employed a non-linear ANSYS Code. The results show a temperature increase up to 341^ oC for a single step of 4 sec. The stresses and deformations on the component which has undergone a cycled load are within the limits of the allowable values. The design layout of the First Wall has been finalized, taking into account all requirements of the IGNITOR Machine. The electrical diagnostics placed inside the plasma chamber have been included in the tile carrier design. The First Wall has been tailored with special consideration for the Faraday Shield facing the ports through which ICRH is injected. *Sponsored in part by ENEA of Italy and by the U.S. DOE.

  8. Effect of occlusal vertical dimension on lip positions at smile. (United States)

    Chou, Jang-Ching; Thompson, Geoffrey A; Aggarwal, Harshit A; Bosio, Jose A; Irelan, Jon P


    In complete mouth reconstructive dentistry, the occlusal vertical dimension may be increased to provide adequate restorative space or to improve esthetics. The effect of increasing the occlusal vertical dimension on the smile is not well understood. The purpose of this study was to evaluate the effect of increasing the occlusal vertical dimension on the dimensions of the smile. Thirty dental students, 12 men and 18 women between the ages of 21 and 30 years old, participated in this study. Polyvinyl siloxane occlusal registrations 2, 4, 6, and 8 mm in thickness were fabricated from articulated stone casts. Posed smile images at occlusal vertical dimension +0, +2, +4, +6, and +8 mm were made with a digital single lens reflex camera mounted on a tripod. A wall-mounted head-positioning device, modified from a cephalometric unit, was used to stabilize the head position. Interlabial gap height, intercommissural width, incisal edge to upper lip, and incisal edge-to-lower lip measurements were made with computer software. The smile index was obtained by dividing width by height. The display zone area was measured by using computer software tracing. One-way repeated measures ANOVA (α=.05) was used for statistical analysis. With an increase in the occlusal vertical dimension, the interlabial gap height, incisal edge to lower lip distance, and display zone area increased significantly (Pdimension. The smile index decreases with increased occlusal vertical dimension. However, the width of the smile and the length of the upper lip tend to remain unchanged. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  9. The ins and outs of modelling vertical displacement events (United States)

    Pfefferle, David


    Of the many reasons a plasma discharge disrupts, Vertical Displacement Events (VDEs) lead to the most severe forces and stresses on the vacuum vessel and Plasma Facing Components (PFCs). After loss of positional control, the plasma column drifts across the vacuum vessel and comes in contact with the first wall, at which point the stored magnetic and thermal energy is abruptly released. The vessel forces have been extensively modelled in 2D but, with the constraint of axisymmetry, the fundamental 3D effects that lead to toroidal peaking, sideways forces, field-line stochastisation and halo current rotation have been vastly overlooked. In this work, we present the main results of an intense VDE modelling activity using the implicit 3D extended MHD code M3D-C1 and share our experience with the multi-domain and highly non-linear physics encountered. At the culmination of code development by the M3D-C1 group over the last decade, highlighted by the inclusion of a finite-thickness resistive vacuum vessel within the computational domain, a series of fully 3D non-linear simulations are performed using realistic transport coefficients based on the reconstruction of so-called NSTX frozen VDEs, where the feedback control was purposely switched off to trigger a vertical instability. The vertical drift phase, the evolution of the current quench and the onset of 3D halo/eddy currents are diagnosed and investigated in detail. The sensitivity of the current quench to parameter changes is assessed via 2D non-linear runs. The growth of individual toroidal modes is monitored via linear-complex runs. The intricate evolution of the plasma, which is decaying to large extent in force-balance with induced halo/wall currents, is carefully resolved via 3D non-linear runs. The location, amplitude and rotation of normal currents and wall forces are analysed and compared with experimental traces.

  10. Advanced high performance vertical hybrid synthetic jet actuator (United States)

    Xu, Tian-Bing (Inventor); Jiang, Xiaoning (Inventor); Su, Ji (Inventor)


    The present invention comprises a high performance, vertical, zero-net mass-flux, synthetic jet actuator for active control of viscous, separated flow on subsonic and supersonic vehicles. The present invention is a vertical piezoelectric hybrid zero-net mass-flux actuator, in which all the walls of the chamber are electrically controlled synergistically to reduce or enlarge the volume of the synthetic jet actuator chamber in three dimensions simultaneously and to reduce or enlarge the diameter of orifice of the synthetic jet actuator simultaneously with the reduction or enlargement of the volume of the chamber. The jet velocity and mass flow rate for the present invention will be several times higher than conventional piezoelectric synthetic jet actuators.

  11. Damage Accumulation in Vertical Breakwaters due to Combined Impact Loading and Pulsating Wave Loads

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Nielsen, Søren R. K.


    Vertical wall breakwaters used to protect for example an harbour from large waves usually consist of large concrete caissons placed on the seabed. The wave loads can be divided in two types, pulsating and impact loads. For some types of breakwaters especially the impact wave loads can be very large...

  12. Mixed convection of micropolar fluid in a vertical double-passage ...

    African Journals Online (AJOL)

    The effect of the presence of a thin perfectly conductive baffle on the fully developed laminar mixed convection in a vertical channel containing micropolar fluid is analyzed. The channel has different constant wall temperatures. Analytical expressions for velocity and microrotation velocity are obtained. The solutions are ...

  13. Integrating shotcrete walls into the natural landscape by application of 'Green Walls' (United States)

    Medl, Alexandra; Kikuta, Silvia


    Steep slopes resulting from major road infrastructure constructions are increasingly perceived as disagreeable disturbance in the landscape. Thus, a tool to consider landscape aspects and integrate these slopes into the natural environment is required. The challenge is to establish a sustainable vegetation layer despite of adverse circumstances such as inclinations of almost 90⁰, exposed position of slopes near streets and lack of soil and water supply. The objective of this study was to assess the performance of an innovative greening technology for vertical structures (shotcrete wall) in terms of vegetation development on varying plant substrates and geotextiles. The field experiment in Steinach am Brenner, Tyrol, Austria, included testing three plant substrates on basis of nearby rocky excavation material ('Innsbrucker Quarzphyllit', 'Bündnerschiefer' and 'Zentralgneis') combined with compost. Additionally, five geotextiles (geogrid (3x4 mm), geogrid (9x10 mm), coir net, coir mat, geo mat) were applied for evaluation. All test combinations were evaluated regarding vegetation cover and biomass production from 2015 to 2016. Analyses of chemical properties were conducted for all plant substrates. Results showed highest vegetation cover ratio on 'Bündnerschiefer' and 'Innsbrucker Quarzphyllit', which can be explained by the favorable mineral composition (nutrient storage capacity) and chemical properties of compost (lower values of electrical conductivity and C/N ratio). In conclusion, the use of 'Green Walls' filled with 'Bündnerschiefer' or 'Innsbrucker Quarzphyllit' plant substrate in combination with netlike geotextiles proved best, since geo grid and coir net turned out as most successful one year after installation. 'Green Walls' are promising in terms of establishing an optimal vegetation cover on vertical structures and are well suited for integrating shotcrete walls into the landscape. The use of local excavation material for greening purposes can be

  14. Waves, circulation and vertical dependence (United States)

    Mellor, George


    Longuet-Higgins and Stewart (J Fluid Mech 13:481-504, 1962; Deep-Sea Res 11:529-562, 1964) and later Phillips (1977) introduced the problem of waves incident on a beach, from deep to shallow water. From the wave energy equation and the vertically integrated continuity equation, they inferred velocities to be Stokes drift plus a return current so that the vertical integral of the combined velocities was nil. As a consequence, it can be shown that velocities of the order of Stokes drift rendered the advective term in the momentum equation negligible resulting in a simple balance between the horizontal gradients of the vertically integrated elevation and wave radiation stress terms; the latter was first derived by Longuet-Higgins and Stewart. Mellor (J Phys Oceanogr 33:1978-1989, 2003a), noting that vertically integrated continuity and momentum equations were not able to deal with three-dimensional numerical or analytical ocean models, derived a vertically dependent theory of wave-circulation interaction. It has since been partially revised and the revisions are reviewed here. The theory is comprised of the conventional, three-dimensional, continuity and momentum equations plus a vertically distributed, wave radiation stress term. When applied to the problem of waves incident on a beach with essentially zero turbulence momentum mixing, velocities are very large and the simple balance between elevation and radiation stress gradients no longer prevails. However, when turbulence mixing is reinstated, the vertically dependent radiation stresses produce vertical velocity gradients which then produce turbulent mixing; as a consequence, velocities are reduced, but are still larger by an order of magnitude compared to Stokes drift. Nevertheless, the velocity reduction is sufficient so that elevation set-down obtained from a balance between elevation gradient and radiation stress gradients is nearly coincident with that obtained by the aforementioned papers. This paper

  15. Moisture Research - Optimizing Wall Assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Arena, Lois [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States); Mantha, Pallavi [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States)


    In this project, the Consortium for Advanced Residential Buildings (CARB) team evaluated several different configurations of wall assemblies to determine the accuracy of moisture modeling and make recommendations to ensure durable, efficient assemblies. WUFI and THERM were used to model the hygrothermal and heat transfer characteristics of these walls. Wall assemblies evaluated included code minimum walls using spray foam insulation and fiberglass batts, high R-value walls at least 12 in. thick (R-40 and R-60 assemblies), and brick walls with interior insulation.

  16. Turbulent mixed convection in asymmetrically heated vertical channel

    Directory of Open Access Journals (Sweden)

    Mokni Ameni


    Full Text Available In this paper an investigation of mixed convection from vertical heated channel is undertaken. The aim is to explore the heat transfer obtained by adding a forced flow, issued from a flat nozzle located in the entry section of a channel, to the up-going fluid along its walls. Forced and free convection are combined studied in order to increase the cooling requirements. The study deals with both symmetrically and asymmetrically heated channel. The Reynolds number based on the nozzle width and the jet velocity is assumed to be 3 103 and 2.104; whereas, the Rayleigh number based on the channel length and the wall temperature difference varies from 2.57 1010 to 5.15 1012. The heating asymmetry effect on the flow development including the mean velocity and temperature the local Nusselt number, the mass flow rate and heat transfer are examined.

  17. Magnetic vortices as localized mesoscopic domain wall pinning sites (United States)

    Novak, R. L.; Sampaio, L. C.


    We report on the controllable pinning of domain walls in a stripe with perpendicular magnetic anisotropy by magnetostatic coupling to a magnetic vortex in disks located above the stripe. Pinning mechanisms and depinning fields, studied by means of micromagnetic simulations, are reported. An asymmetric magnetization reversal process is observed and explained in terms of two main contributions to the domain wall pinning: coupling between the in-plane and out-of-plane components of its stray field and the vortex. The in-plane coupling is symmetric with respect to the wall sense of motion while the out-of-plane coupling leads to the observed asymmetry in the hysteresis loops. The energy landscape of the domain wall derived from the micromagnetic simulations supports these findings. This novel pinning strategy, which can be realized by current nanofabrication techniques, opens up new possibilities for the non-destructive control of domain wall mobility in domain wall based spintronic devices.

  18. Simplified numerical study of evaporation processes inside vertical tubes (United States)

    Ocłoń, Paweł; Nowak, Marzena; Łopata, Stanisław


    The paper presents a simplified numerical model of evaporation processes inside vertical tubes. In this model only the temperature fields in the fluid domain (the liquid or two-phase mixture) and solid domain (a tube wall) are determined. Therefore its performance and efficiency is high. The analytical formulas, which allow calculating the pressure drop and the distribution of heat transfer coefficient along the tube length, are used in this model. The energy equation for the fluid domain is solved with the Control Volume Method and for the solid domain with the Finite Element Method in order to determine the temperature field for the fluid and solid domains.

  19. Experimental characterization of vertical-axis wind turbine noise. (United States)

    Pearson, C E; Graham, W R


    Vertical-axis wind turbines are wind-energy generators suitable for use in urban environments. Their associated noise thus needs to be characterized and understood. As a first step, this work investigates the relative importance of harmonic and broadband contributions via model-scale wind-tunnel experiments. Cross-spectra from a pair of flush-mounted wall microphones exhibit both components, but further analysis shows that the broadband dominates at frequencies corresponding to the audible range in full-scale operation. This observation has detrimental implications for noise-prediction reliability and hence also for acoustic design optimization.

  20. SWCNT-MoS2 -SWCNT Vertical Point Heterostructures. (United States)

    Zhang, Jin; Wei, Yang; Yao, Fengrui; Li, Dongqi; Ma, He; Lei, Peng; Fang, Hehai; Xiao, Xiaoyang; Lu, Zhixing; Yang, Juehan; Li, Jingbo; Jiao, Liying; Hu, Weida; Liu, Kaihui; Liu, Kai; Liu, Peng; Li, Qunqing; Lu, Wei; Fan, Shoushan; Jiang, Kaili


    A vertical point heterostructure (VPH) is constructed by sandwiching a two-dimensional (2D) MoS2 flake with two cross-stacked metallic single-walled carbon nanotubes. It can be used as a field-effect transistor with high on/off ratio and a light detector with high spatial resolution. Moreover, the hybrid 1D-2D-1D VPHs open up new possibilities for nanoelectronics and nano-optoelectronics. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Turbine airfoil with a compliant outer wall (United States)

    Campbell, Christian X [Oviedo, FL; Morrison, Jay A [Oviedo, FL


    A turbine airfoil usable in a turbine engine with a cooling system and a compliant dual wall configuration configured to enable thermal expansion between inner and outer layers while eliminating stress formation in the outer layer is disclosed. The compliant dual wall configuration may be formed a dual wall formed from inner and outer layers separated by a support structure. The outer layer may be a compliant layer configured such that the outer layer may thermally expand and thereby reduce the stress within the outer layer. The outer layer may be formed from a nonplanar surface configured to thermally expand. In another embodiment, the outer layer may be planar and include a plurality of slots enabling unrestricted thermal expansion in a direction aligned with the outer layer.

  2. Dispersive Stiffness of Dzyaloshinskii Domain Walls (United States)

    Pellegren, J. P.; Lau, D.; Sokalski, V.


    It is well documented that subjecting perpendicular magnetic films that exhibit the interfacial Dzyaloshinskii-Moriya interaction to an in-plane magnetic field results in a domain wall (DW) energy σ , which is highly anisotropic with respect to the orientation of the DW in the film plane Θ . We demonstrate that this anisotropy has a profound impact on the elastic response of the DW as characterized by the surface stiffness σ ˜ (Θ )=σ (Θ )+σ''(Θ ) and evaluate its dependence on the length scale of deformation. The influence of stiffness on DW mobility in the creep regime is assessed, with analytic and numerical calculations showing trends in σ ˜ that better represent experimental measurements of domain wall velocity in magnetic thin films compared to σ alone. Our treatment provides experimental support for theoretical models of the mobility of anisotropic elastic manifolds and makes progress toward a more complete understanding of magnetic domain wall creep.

  3. A Survey of Wall Climbing Robots: Recent Advances and Challenges


    Shunsuke Nansai; Rajesh Elara Mohan


    In recent decades, skyscrapers, as represented by the Burj Khalifa in Dubai and Shanghai Tower in Shanghai, have been built due to the improvements of construction technologies. Even in such newfangled skyscrapers, the façades are generally cleaned by humans. Wall climbing robots, which are capable of climbing up vertical surfaces, ceilings and roofs, are expected to replace the manual workforce in façade cleaning works, which is both hazardous and laborious work. Such tasks require these rob...

  4. Passive wall cooling panel with phase change material as a cooling agent (United States)

    Majid, Masni A.; Tajudin, Rasyidah Ahmad; Salleh, Norhafizah; Hamid, Noor Azlina Abd


    The study was carried out to the determine performance of passive wall cooling panels by using Phase Change Materials as a cooling agent. This passive cooling system used cooling agent as natural energy storage without using any HVAC system. Eight full scale passive wall cooling panels were developed with the size 1500 mm (L) × 500 mm (W) × 100 mm (T). The cooling agent such as glycerine were filled in the tube with horizontal and vertical arrangement. The passive wall cooling panels were casting by using foamed concrete with density between 1200 kg/m3 – 1500 kg/m3. The passive wall cooling panels were tested in a small house and the differences of indoor and outdoor temperature was recorded. Passive wall cooling panels with glycerine as cooling agent in vertical arrangement showed the best performance with dropped of indoor air temperature within 3°C compared to outdoor air temperature. The lowest indoor air temperature recorded was 25°C from passive wall cooling panels with glycerine in vertical arrangement. From this study, the passive wall cooling system could be applied as it was environmental friendly and less maintenance.

  5. High-R Walls for Remodeling: Wall Cavity Moisture Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Wiehagen, J.; Kochkin, V.


    The focus of the study is on the performance of wall systems, and in particular, the moisture characteristics inside the wall cavity and in the wood sheathing. Furthermore, while this research will initially address new home construction, the goal is to address potential moisture issues in wall cavities of existing homes when insulation and air sealing improvements are made.

  6. High-R Walls for Remodeling. Wall Cavity Moisture Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Wiehagen, J. [NAHB Research Center Industry Partnership, Upper Marlboro, MD (United States); Kochkin, V. [NAHB Research Center Industry Partnership, Upper Marlboro, MD (United States)


    The focus of the study is on the performance of wall systems, and in particular, the moisture characteristics inside the wall cavity and in the wood sheathing. Furthermore, while this research will initially address new home construction, the goal is to address potential moisture issues in wall cavities of existing homes when insulation and air sealing improvements are made.

  7. Hybrid Vertical-Cavity Laser

    DEFF Research Database (Denmark)


    The present invention provides a light source (2) for light circuits on a silicon platform (3). A vertical laser cavity is formed by a gain region (101) arranged between a top mirror (4) and a bottom grating-mirror (12) in a grating region (11) in a silicon layer (10) on a substrate. A waveguide...

  8. Physics and the Vertical Jump (United States)

    Offenbacher, Elmer L.


    The physics of vertical jumping is described as an interesting illustration for motivating students in a general physics course to master the kinematics and dynamics of one dimensional motion. The author suggests that mastery of the physical principles of the jump may promote understanding of certain biological phenomena, aspects of physical…

  9. Multiservice Vertical Handoff Decision Algorithms

    Directory of Open Access Journals (Sweden)

    Zhu Fang


    Full Text Available Future wireless networks must be able to coordinate services within a diverse-network environment. One of the challenging problems for coordination is vertical handoff, which is the decision for a mobile node to handoff between different types of networks. While traditional handoff is based on received signal strength comparisons, vertical handoff must evaluate additional factors, such as monetary cost, offered services, network conditions, and user preferences. In this paper, several optimizations are proposed for the execution of vertical handoff decision algorithms, with the goal of maximizing the quality of service experienced by each user. First, the concept of policy-based handoffs is discussed. Then, a multiservice vertical handoff decision algorithm (MUSE-VDA and cost function are introduced to judge target networks based on a variety of user- and network-valued metrics. Finally, a performance analysis demonstrates that significant gains in the ability to satisfy user requests for multiple simultaneous services and a more efficient use of resources can be achieved from the MUSE-VDA optimizations.


    Energy Technology Data Exchange (ETDEWEB)

    Sampayan, S; Caporaso, G; Chen, Y; Harris, J; Hawkins, S; Holmes, C; Nelson, S; Poole, B; Rhodes, M; Sanders, D; Sullivan, J; Wang, L; Watson, J


    The dielectric wall accelerator (DWA) is a compact pulsed power device where the pulse forming lines, switching, and vacuum wall are integrated into a single compact geometry. For this effort, we initiated a extensive compact pulsed power development program and have pursued the study of switching (gas, oil, laser induced surface flashover and photoconductive), dielectrics (ceramics and nanoparticle composites), pulse forming line topologies (asymmetric and symmetric Blumleins and zero integral pulse forming lines), and multilayered vacuum insulator (HGI) technology. Finally, we fabricated an accelerator cell for test on ETAII (a 5.5 MeV, 2 kA, 70 ns pulsewidth electron beam accelerator). We review our past results and report on the progress of accelerator cell testing.

  11. Partial domain wall partition functions

    National Research Council Canada - National Science Library

    Foda, O; Wheeler, M


    We consider six-vertex model configurations on an (n × N) lattice, n ≤ N, that satisfy a variation on domain wall boundary conditions that we define and call partial domain wall boundary conditions...

  12. Scalable Resolution Display Walls

    KAUST Repository

    Leigh, Jason


    This article will describe the progress since 2000 on research and development in 2-D and 3-D scalable resolution display walls that are built from tiling individual lower resolution flat panel displays. The article will describe approaches and trends in display hardware construction, middleware architecture, and user-interaction design. The article will also highlight examples of use cases and the benefits the technology has brought to their respective disciplines. © 1963-2012 IEEE.

  13. Light shining through walls

    Energy Technology Data Exchange (ETDEWEB)

    Redondo, Javier [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Max-Planck-Institut fuer Physik, Muenchen (Germany); Ringwald, Andreas [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)


    Shining light through walls? At first glance this sounds crazy. However, very feeble gravitational and electroweak effects allow for this exotic possibility. Unfortunately, with present and near future technologies the opportunity to observe light shining through walls via these effects is completely out of question. Nevertheless there are quite a number of experimental collaborations around the globe involved in this quest. Why are they doing it? Are there additional ways of sending photons through opaque matter? Indeed, various extensions of the standard model of particle physics predict the existence of new particles called WISPs - extremely weakly interacting slim particles. Photons can convert into these hypothetical particles, which have no problems to penetrate very dense materials, and these can reconvert into photons after their passage - as if light was effectively traversing walls. We review this exciting field of research, describing the most important WISPs, the present and future experiments, the indirect hints from astrophysics and cosmology pointing to the existence of WISPs, and finally outlining the consequences that the discovery of WISPs would have. (orig.)

  14. Microfluidics with fluid walls. (United States)

    Walsh, Edmond J; Feuerborn, Alexander; Wheeler, James H R; Tan, Ann Na; Durham, William M; Foster, Kevin R; Cook, Peter R


    Microfluidics has great potential, but the complexity of fabricating and operating devices has limited its use. Here we describe a method - Freestyle Fluidics - that overcomes many key limitations. In this method, liquids are confined by fluid (not solid) walls. Aqueous circuits with any 2D shape are printed in seconds on plastic or glass Petri dishes; then, interfacial forces pin liquids to substrates, and overlaying an immiscible liquid prevents evaporation. Confining fluid walls are pliant and resilient; they self-heal when liquids are pipetted through them. We drive flow through a wide range of circuits passively by manipulating surface tension and hydrostatic pressure, and actively using external pumps. Finally, we validate the technology with two challenging applications - triggering an inflammatory response in human cells and chemotaxis in bacterial biofilms. This approach provides a powerful and versatile alternative to traditional microfluidics.The complexity of fabricating and operating microfluidic devices limits their use. Walsh et al. describe a method in which circuits are printed as quickly and simply as writing with a pen, and liquids in them are confined by fluid instead of solid walls.

  15. Wall Street som kreationistisk forkynder

    DEFF Research Database (Denmark)

    Ekman, Susanne


    Artiklen gennemgår Karen Hos etnografi om Wall Street: "Liquidated: An ethnography of Wall Street" set i lyset af den offentlige debat vedrørende Goldman Sachs opkøb af Dong......Artiklen gennemgår Karen Hos etnografi om Wall Street: "Liquidated: An ethnography of Wall Street" set i lyset af den offentlige debat vedrørende Goldman Sachs opkøb af Dong...

  16. Metals attenuation in minerally-enhanced slurry walls

    Energy Technology Data Exchange (ETDEWEB)

    Evans, J.C.; Prince, M.J. [Bucknell Univ., Lewisburg, PA (United States); Adams, T.L. [Woodward-Clyde Consultants, Blue Bell, PA (United States)


    In current practice, a soil-bentonite slurry trench cutoff wall is a mixture of water, soil, and bentonite that is designed to serve as a passive barrier to ground water and contaminant transport. This study evaluated the transformation of a passive slurry trench cutoff wall barrier to an active barrier system. Conventional soil-bentonite vertical barriers presently serve as passive barriers to contaminated ground water. An active barrier will not only fulfill the functions of the present passive barrier system, but also retard contaminant transport by adsorptive processes. Attapulgite, Na-chabazite, and Ca-chabazite were added to {open_quotes}activate{close_quotes} the conventional soil-bentonite backfill. Batch extraction tests were performed to determine the partitioning coefficients of cadmium and zinc between the liquid and solid phase when in contact with the backfill mixes. Batch extraction and mathematical modeling results demonstrate the ability of an active barrier to retard the transport of cadmium and zinc. The reactivity of the soil-bentonite vertical barrier depends heavily on the inorganic being adsorbed. The reactivity of the barrier also depends on the adsorptive capabilities of the clay minerals added to the conventional soil-bentonite vertical barrier. The results of laboratory studies suggest that passive barrier systems can be transformed to active systems. Further, the data suggests that although conventional soil-bentonite vertical barriers are presently designed as passive barriers, they already have adsorptive capacity associated with active barriers.

  17. Domain walls on the brane

    NARCIS (Netherlands)

    Bergshoeff, E; van der Schaar, JP; Papadopoulos, G


    We show that all branes admit worldvolume domain wall solutions. We find one class of solutions for which the tension of the brane changes discontinuously along the domain wall. These solutions are not supersymmetric. We argue that there is another class of domain wall solutions which is

  18. Build an Interactive Word Wall (United States)

    Jackson, Julie


    Word walls visually display important vocabulary covered during class. Although teachers have often been encouraged to post word walls in their classrooms, little information is available to guide them. This article describes steps science teachers can follow to transform traditional word walls into interactive teaching tools. It also describes a…

  19. Indoor climbing walls in Prague


    Schwarzová, Veronika


    This work presents the indoor climbing walls in climbing centers for the public in Prague. It creates an overview of qualitative and quantitative characteristics of indoor climbing walls in Prague. Thesis allowing ordinary users and the general public interested in climbing easier selection of the appropriate climbing wall according on their level, the safety requirements, background, but also the place of residence.

  20. Cell wall biology: perspectives from cell wall imaging. (United States)

    Lee, Kieran J D; Marcus, Susan E; Knox, J Paul


    Polysaccharide-rich plant cell walls are important biomaterials that underpin plant growth, are major repositories for photosynthetically accumulated carbon, and, in addition, impact greatly on the human use of plants. Land plant cell walls contain in the region of a dozen major polysaccharide structures that are mostly encompassed by cellulose, hemicelluloses, and pectic polysaccharides. During the evolution of land plants, polysaccharide diversification appears to have largely involved structural elaboration and diversification within these polysaccharide groups. Cell wall chemistry is well advanced and a current phase of cell wall science is aimed at placing the complex polysaccharide chemistry in cellular contexts and developing a detailed understanding of cell wall biology. Imaging cell wall glycomes is a challenging area but recent developments in the establishment of cell wall molecular probe panels and their use in high throughput procedures are leading to rapid advances in the molecular understanding of the spatial heterogeneity of individual cell walls and also cell wall differences at taxonomic levels. The challenge now is to integrate this knowledge of cell wall heterogeneity with an understanding of the molecular and physiological mechanisms that underpin cell wall properties and functions.

  1. Wall Area of Influence and Growing Wall Heat Transfer due to Sliding Bubbles in Subcooled Boiling Flow

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Junsoo; Estrada-Perez, Carlos E.; Hassan, Yassin A.


    A variety of dynamical features of sliding bubbles and their impact on wall heat transfer were observed at subcooled flow boiling conditions in a vertical square test channel. Among the wide range of parameters observed, we particularly focus in this paper on (i) the sliding bubbles’ effect on wall heat transfer (supplemantry discussion to the authors’ previous work in Yoo et al. (2016a,b)) and (ii) the wall area influenced by sliding bubbles in subcooled boiling flow. At first, this study reveals that the degree of wall heat transfer improvement due to sliding bubbles depended less on the wall superheat condition as the mass flux increased. Also, the sliding bubble trajectory was found to be one of the critical factors in order to properly describe the wall heat transfer associated with sliding bubbles. In particular, the wall area influenced by sliding bubbles depended strongly on both sliding bubble trajectory and sliding bubble size; the sliding bubble trajectory was also observed to be closely related to the sliding bubble size. Importantly, these results indicate the limitation of current approach in CFD analyses especially for the wall area of bubble influence. In addition, the analyses on the temporal fraction of bubbles’ residence (FR) along the heated wall show that the sliding bubbles typically travel through narrow path with high frequency while the opposite was observed downstream. That is, both FR and sliding bubble trajectory depended substantially on the distance from nucleation site, which is expected to be similar for the quenching heat transfer mode induced by sliding bubbles.

  2. Vertical Integration at Junior and Intermediate Levels. School Research Newsletter. (United States)

    Marklund, Inger, Ed.; Hanse, Mona-Britt, Ed.


    In recent years, there has been a rapid growth of interest in Sweden in vertically integrated classes in compulsory schools, especially at junior high school and intermediate grade levels. This development is supported in various ways by the curriculum, partly because it puts more emphasis than previous curricula on the occurrence of teaching…

  3. A carbon nanotube wall membrane for water treatment. (United States)

    Lee, Byeongho; Baek, Youngbin; Lee, Minwoo; Jeong, Dae Hong; Lee, Hong H; Yoon, Jeyong; Kim, Yong Hyup


    Various forms of carbon nanotubes have been utilized in water treatment applications. The unique characteristics of carbon nanotubes, however, have not been fully exploited for such applications. Here we exploit the characteristics and corresponding attributes of carbon nanotubes to develop a millimetre-thick ultrafiltration membrane that can provide a water permeability that approaches 30,000 l m(-2) h(-1) bar(-1), compared with the best water permeability of 2,400 l m(-2) h(-1) bar(-1) reported for carbon nanotube membranes. The developed membrane consists only of vertically aligned carbon nanotube walls that provide 6-nm-wide inner pores and 7-nm-wide outer pores that form between the walls of the carbon nanotubes when the carbon nanotube forest is densified. The experimental results reveal that the permeance increases as the pore size decreases. The carbon nanotube walls of the membrane are observed to impede bacterial adhesion and resist biofilm formation.

  4. Left ventricular wall stress compendium. (United States)

    Zhong, L; Ghista, D N; Tan, R S


    Left ventricular (LV) wall stress has intrigued scientists and cardiologists since the time of Lame and Laplace in 1800s. The left ventricle is an intriguing organ structure, whose intrinsic design enables it to fill and contract. The development of wall stress is intriguing to cardiologists and biomedical engineers. The role of left ventricle wall stress in cardiac perfusion and pumping as well as in cardiac pathophysiology is a relatively unexplored phenomenon. But even for us to assess this role, we first need accurate determination of in vivo wall stress. However, at this point, 150 years after Lame estimated left ventricle wall stress using the elasticity theory, we are still in the exploratory stage of (i) developing left ventricle models that properly represent left ventricle anatomy and physiology and (ii) obtaining data on left ventricle dynamics. In this paper, we are responding to the need for a comprehensive survey of left ventricle wall stress models, their mechanics, stress computation and results. We have provided herein a compendium of major type of wall stress models: thin-wall models based on the Laplace law, thick-wall shell models, elasticity theory model, thick-wall large deformation models and finite element models. We have compared the mean stress values of these models as well as the variation of stress across the wall. All of the thin-wall and thick-wall shell models are based on idealised ellipsoidal and spherical geometries. However, the elasticity model's shape can vary through the cycle, to simulate the more ellipsoidal shape of the left ventricle in the systolic phase. The finite element models have more representative geometries, but are generally based on animal data, which limits their medical relevance. This paper can enable readers to obtain a comprehensive perspective of left ventricle wall stress models, of how to employ them to determine wall stresses, and be cognizant of the assumptions involved in the use of specific models.

  5. Scale resolving computation of submerged wall jets on flat wall with different roughness heights (United States)

    Paik, Joongcheol; Bombardelli, Fabian


    Scale-adaptive simulation is used to investigate the response of velocity and turbulence in submerged wall jets to abrupt changes from smooth to rough beds. The submerged wall jets were experimentally investigated by Dey and Sarkar [JFM, 556, 337, 2006] at the Reynolds number of 17500 the Froude number of 4.09 and the submergence ratio of 1.12 on different rough beds that were generated by uniform sediments of different median diameters The SAS is carried out by means of a second-order-accurate finite volume method in space and time and the effect of bottom roughness is treated by the approach of Cebeci (2004). The evolution of free surface is captured by employing the two-phase volume of fluid (VOF) technique. The numerical results obtained by the SAS approach, incorporated with the VOF and the rough wall treatment, are in good agreement with the experimental measurements. The computed turbulent boundary layer grows more quickly and the depression of the free surface is more increased on the rough wall than those on smooth wall. The size of the fully developed zone shrinks and the decay rate of maximum streamwise velocity and Reynolds stress components are faster with increase in the wall roughness. Supported by NSF and NRF of Korea.

  6. Load carrying capacity of shear wall t-connections reinforced with high strength wire ropes

    DEFF Research Database (Denmark)

    Jørgensen, Henrik B.; Bryndom, Thor; Larsen, Michael


    Traditionally, U-bar loop connections with keyed joints have been used in vertical shear connections between precast concrete wall elements. However, in the recent years, connections with looped high strength wire ropes instead of U-bar loops have proven to be a much more construction......-friendly solution. The wire ropes have no bending stiffness and therefore allow for an easier vertical installation of the wall elements. During the last 10 – 15 years, a number of shear tests on plane wire rope connections have been carried out. However, to the best knowledge of the authors, tests on wire rope...

  7. Load Carrying Capacity of Shear Wall T-Connections Reinforced with High Strength Wire Ropes

    DEFF Research Database (Denmark)

    Jørgensen, Henrik Brøner; Bryndum, Thor; Larsen, Michael


    Traditionally, U-bar loop connections with keyed joints have been used in vertical shear connections between precast concrete wall elements. However, in the recent years, connections with looped high strength wire ropes instead of U-bar loops have proven to be a much more construction......-friendly solution. The wire ropes have no bending stiffness and therefore allow for an easier vertical installation of the wall elements. During the last 10 – 15 years, a number of shear tests on plane wire rope connections have been carried out. However, to the best knowledge of the authors, tests on wire rope...

  8. Moisture movements in render on brick wall

    DEFF Research Database (Denmark)

    Hansen, Kurt Kielsgaard; Munch, Thomas Astrup; Thorsen, Peter Schjørmann


    A three-layer render on brick wall used for building facades is studied in the laboratory. The vertical render surface is held in contact with water for 24 hours simulating driving rain while it is measured with non-destructive X-ray equipment every hour in order to follow the moisture front...... through the render and into the brick. The test specimen is placed between the source and the detector. The test specimens are all scanned before they are exposed to water. In that way the loss of counts from the dry scan to the wet scan qualitatively shows the presence of water. The results show nearly...... no penetration of water through the render and into the brick, and the results are independent of the start condition of the test specimens. Also drying experiments are performed. The results show a small difference in the rate of drying, in favour of the bricks without render....

  9. Coexistence of Strategic Vertical Separation and Integration

    DEFF Research Database (Denmark)

    Jansen, Jos


    This paper gives conditions under which vertical separation is chosen by some upstream firms, while vertical integration is chosen by others in the equilibrium of a symmetric model. A vertically separating firm trades off fixed contracting costs against the strategic benefit of writing a (two......-part tariff, exclusive dealing) contract with its retailer. Coexistence emerges when more than two vertical Cournot oligopolists supply close substitutes. When vertical integration and separation coexist, welfare could be improved by reducing the number of vertically separating firms. The scope...

  10. Kinematic Fitting of Detached Vertices

    Energy Technology Data Exchange (ETDEWEB)

    Mattione, Paul [Rice Univ., Houston, TX (United States)


    The eg3 experiment at the Jefferson Lab CLAS detector aims to determine the existence of the $\\Xi_{5}$ pentaquarks and investigate the excited $\\Xi$ states. Specifically, the exotic $\\Xi_{5}^{--}$ pentaquark will be sought by first reconstructing the $\\Xi^{-}$ particle through its weak decays, $\\Xi^{-}\\to\\pi^{-}\\Lambda$ and $\\Lambda\\to\\pi^{-}$. A kinematic fitting routine was developed to reconstruct the detached vertices of these decays, where confidence level cuts on the fits are used to remove background events. Prior to fitting these decays, the exclusive reaction $\\gamma D\\rightarrow pp\\pi^{-}$ was studied in order to correct the track measurements and covariance matrices of the charged particles. The $\\Lambda\\rightarrow p\\pi^{-}$ and $\\Xi^{-}\\to\\pi^{-}\\Lambda$ decays were then investigated to demonstrate that the kinematic fitting routine reconstructs the decaying particles and their detached vertices correctly.

  11. Vertical distribution of Arctic methane (United States)

    Tukiainen, Simo; Karppinen, Tomi; Hakkarainen, Janne; Kivi, Rigel; Heikkinen, Pauli; Tamminen, Johanna


    In this study we show the vertical distribution of atmospheric methane (CH4) measured in Sodankylä, Northern Finland. The CH4 profiles are retrieved from the direct Sun FTS measurements using the dimension reduction retrieval method. In the retrieval method, we have a few degrees of freedom about the profile shape. The data set covers years 2010-2016 (from February to November) and altitudes 0-40 km. The retrieved FTS profiles are validated against ACE satellite measurements and AirCore balloon measurements. The total columns derived from the FTS profiles are compared to the official TCCON XCH4 data. A vertically resolved methane data set can be used, e.g., to study stratospheric methane during the polar vortex.


    Directory of Open Access Journals (Sweden)

    Furia Donatella


    Full Text Available During the last decades, market segmentation and intra-industry trade have become increasingly relevant. The underlying hypothesis of our work is that distinct articles have heterogeneous potential for vertical differentiation, implying that different patterns of international specialization should be identifiable. We carry out an analysis on revealed comparative advantage (through the Lafay Index in specific sectors of interest. Then we highlight the emergence of diverse degrees of product quality differentiation among sectors (through the Relative Quality Index. Results confirm our hypothesis. Indeed it appears that only certain goods, for which the pace of either creative or technological innovation (or both is particularly fast, present a high degree of vertical differentiation and market segmentation. This allows countries to specialize in a particular product variety and gain market power position for that variety. These findings should be taken in due consideration when designing trade policies.

  13. Intuitive Mechanics: Inferences of Vertical Projectile Motion

    Directory of Open Access Journals (Sweden)

    Milana Damjenić


    Full Text Available Our intuitive knowledge of physics mechanics, i.e. knowledge defined through personal experience about velocity, acceleration, motion causes, etc., is often wrong. This research examined whether similar misconceptions occur systematically in the case of vertical projectiles launched upwards. The first experiment examined inferences of velocity and acceleration of the ball moving vertically upwards, while the second experiment examined whether the mass of the thrown ball and force of the throw have an impact on the inference. The results showed that more than three quarters of the participants wrongly assumed that maximum velocity and peak acceleration did not occur at the initial launch of the projectile. There was no effect of object mass or effect of the force of the throw on the inference relating to the velocity and acceleration of the ball. The results exceed the explanatory reach of the impetus theory, most commonly used to explain the naive understanding of the mechanics of object motion. This research supports that the actions on objects approach and the property transmission heuristics may more aptly explain the dissidence between perceived and actual implications in projectile motion.

  14. Oocyst wall formation and composition in coccidian parasites

    Directory of Open Access Journals (Sweden)

    Kelly Mai


    Full Text Available The oocyst wall of coccidian parasites is a robust structure that is resistant to a variety of environmental and chemical insults. This resilience allows oocysts to survive for long periods, facilitating transmission from host to host. The wall is bilayered and is formed by the sequential release of the contents of two specialized organelles - wall forming body 1 and wall forming body 2 - found in the macrogametocyte stage of Coccidia. The oocyst wall is over 90% protein but few of these proteins have been studied. One group is cysteine-rich and may be presumed to crosslink via disulphide bridges, though this is yet to be investigated. Another group of wall proteins is rich in tyrosine. These proteins, which range in size from 8-31 kDa, are derived from larger precursors of 56 and 82 kDa found in the wall forming bodies. Proteases may catalyze processing of the precursors into tyrosine-rich peptides, which are then oxidatively crosslinked in a reaction catalyzed by peroxidases. In support of this hypothesis, the oocyst wall has high levels of dityrosine bonds. These dityrosine crosslinked proteins may provide a structural matrix for assembly of the oocyst wall and contribute to its resilience.

  15. Poligonación Vertical

    Directory of Open Access Journals (Sweden)

    Esteban Dörries


    Full Text Available La poligonación vertical es un método de medición de diferencias de altura que aprovecha las posibilidades de las estaciones totales. Se presta fundamentalmente para líneas de nivelación entre nodos formando red. El nombre se debe a que las visuales sucesivas se proyectan sobre aristas verticales en lugar de un plano horizontal, como ocurre en la poligonación convencional.

  16. Vertical Launch System Loadout Planner (United States)


    United States Navy USS United States’ Ship VBA Visual Basic for Applications VLP VLS Loadout Planner VLS Vertical Launch System...mathematically complex and require training to operate the software. A Visual Basic for Applications ( VBA ) Excel (Microsoft Corporation, 2015...lockheed/data/ms2/documents/laun chers/MK41 VLS factsheet.pdf Microsoft Excel version 14.4.3, VBA computer software. (2011). Redmond, WA: Microsoft

  17. Trade Liberalisation and Vertical Integration

    DEFF Research Database (Denmark)

    Bache, Peter Arendorf; Laugesen, Anders

    We build a three-country model of international trade in final goods and intermediate inputs and study the relation between different types of trade liberalisation and vertical integration. Firms are heterogeneous with respect to both productivity and factor intensity as observed in data. Final......-economy property rights theory of the firm using firm-level data. Finally, we notice that our model's sorting pattern is in line with recent evidence when the wage difference across countries is not too big....

  18. Prophylaxis of vertical HBV infection. (United States)

    Pawlowska, Malgorzata; Pniewska, Anna; Pilarczyk, Malgorzata; Kozielewicz, Dorota; Domagalski, Krzysztof


    An appropriate management of HBV infection is the best strategy to finally reduce the total burden of HBV infection. Mother-to-child transmission (MTCT) is responsible for more than one third of chronic HBV infections worldwide. Because HBV infection in infancy or early childhood often leads to chronic infection, appropriate prophylaxis and management of HBV in pregnancy is crucial to prevent MTCT. The prevention of HBV vertical transmission is a complex task and includes: universal HBV screening of pregnant women, administration of antivirals in the third trimester of pregnancy in women with high viral load and passive-active HBV immunoprophylaxis with hepatitis B vaccine and hepatitis B immune globulin in newborns of all HBV infected women. Universal screening of pregnant women for HBV infection, early identification of HBV DNA level in HBV-infected mothers, maternal treatment with class B according to FDA antivirals and passive/active anti-HBV immunoprophylaxis to newborns of HBV-positive mothers are crucial strategies for reducing vertical HBV transmission rates. Consideration of caesarean section in order to reduce the risk of vertical HBV transmission should be recommend in HBV infected pregnant women with high viral load despite antiviral therapy or when the therapy in the third trimester of pregnancy is not available.

  19. Research on seismic performance of slotted RC walls with replaceable damper (United States)

    Wang, Jian; Ou, Jinping; Huo, Lianfeng


    Structural walls are important components of resisting the lateral loads for high-rise structures. However, the traditional walls are difficult to repair or replace in post-earthquake events. Hence, over the past few years, a research was made of several kinds of replaceable structures such as replaceable coupling beam and replaceable wall toe. In this paper, a new seismic energy dissipation wall structure is proposed. The new wall is one with purposely build-in vertical slits within the wall panel, and metallic dampers are installed on the vertical slits so that the seismic performance of the structure can be controlled. Moreover, the metallic damper is easy to be replaced in post-earthquake events. The proposed metallic damper is with a serial of diamond-shaped holes and designed based on the lateral deformation of the wall. The yielding scheme of the metallic damper is proposed in order to achieve the ductility and energy dissipation demand of the walls. The mechanical model of the metallic damper is established. Finally, the numerical simulations of the metallic damper based on the finite element software ABAQUS are presented to validate the effectiveness of the proposed mathematic model.

  20. Sand cracks, horizontal fissures, and other conditions affecting the wall of the bovine claw. (United States)

    Greenough, P R


    The wall of the bovine claw is created only by the dermis beneath the coronary band. Keratogenic tissues in this region are susceptible to nutritional changes or stress, which changes the characteristics of the horn produced. Horizontal grooves or fissures result that weaken the claw wall and are instrumental in generating many vertical fissures. The rate at which the claw grows can be used to calculate the date of a nutritional insult.

  1. Iatrogenic thoracic outlet syndrome secondary to vertical expandable prosthetic titanium rib expansion thoracoplasty: pathogenesis and strategies for prevention/treatment. (United States)

    Nassr, Ahmad; Larson, Annalise Noelle; Crane, Benjamin; Hammerberg, Kim W; Sturm, Peter F; Mardjetko, Steven M


    An innovative treatment for thoracic insufficiency syndrome involves a vertical expansion of the chest wall through a horizontal chest wall osteotomy maintained by a distraction device (vertical expandable prosthetic titanium rib or VEPTR). Upper-extremity neurovascular dysfunction has been reported after expansion. The purposes of this study are to identify potential etiologies for compression of the brachial plexus after expansion thoracoplasty and to suggest strategies to reduce the incidence of this complication. A simulated VEPTR procedure was performed on 8 fresh cadaveric specimens. Manometric measurements were taken in the 3 anatomic regions of the thoracic outlet after thoracotomy and rib distraction were performed. Confirmation of the location of compression was performed by placing barium-impregnated putty along the course of the brachial plexus and evaluating the effect of expansion using video fluoroscopy. A midclavicular osteotomy was then performed and video fluoroscopy repeated. A 20% increase in pressure was seen in the costoclavicular region of the thoracic outlet after expansion. Constriction of the midclavicular region of the thoracic outlet between the first rib and clavicle was confirmed using the putty model. Midclavicular osteotomy alleviated this region of compression. Expansion thoracoplasty with the VEPTR procedure causes increased pressure in the costoclavicular region of the thoracic outlet. A midclavicular osteotomy may be one method to alleviate thoracic outlet narrowing after VEPTR procedure, although the short- and long-term effects of this is procedure is not known. Our model supports an iatrogenic thoracic outlet syndrome caused by expansion thoracoplasty. Based on our data as well as a review of the literature, we recommend intraoperative neurologic monitoring of the ipsilateral upper extremity during the VEPTR procedure.

  2. Investigation of Transient, Turbulent Natural Convection in Vertical Tubes for Thermal Energy Storage in Supercritical CO2 (United States)

    Baghaei Lakeh, Reza; Lavine, Adrienne S.; Kavehpour, H. Pirouz; Wirz, Richard E.


    Heat transfer can be a limiting factor in the operation of thermal energy storage, including sensible heat and latent heat storage systems. Poor heat transfer between the energy storage medium and the container walls impairs the functionality of the thermal storage unit by requiring excessively long times to charge or discharge the system. In this study, the effect of turbulent, unsteady buoyancy-driven flow on heat transfer in vertical storage tubes containing supercritical CO2 as the storage medium is investigated computationally. The heat transfer from a constant-temperature wall to the storage fluid is studied during the charge cycle. The results of this study show that turbulent natural convection dominates the heat transfer mechanism and significantly reduces the required time for charging compared to pure conduction. Changing the L/D ratio of the storage tube has a major impact on the charge time. The charge time shows a decreasing trend with RaL. The non-dimensional model of the problem shows that Nusselt number and non-dimensional mean temperature of the storage fluid in different configurations of the tube is a function Buoyancy-Fourier number defined as of FoL * RaLm* L/D. This study was supported by award No. DE-AR0000140 granted by U.S. Department of Energy under Advanced Research Projects Agency - Energy (ARPA-E) and by award No. 5660021607 granted by Southern California Gas Company.

  3. Asymmetric SOL Current in Vertically Displaced Plasma (United States)

    Cabrera, J. D.; Navratil, G. A.; Hanson, J. M.


    Experiments at the DIII-D tokamak demonstrate a non-monotonic relationship between measured scrape-off layer (SOL) currents and vertical displacement event (VDE) rates with SOL currents becoming largely n=1 dominant as plasma is displaced by the plasma control system (PCS) at faster rates. The DIII-D PCS is used to displace the magnetic axis 10x slower than the intrinsic growth time of similar instabilities in lower single-null plasmas. Low order (n control is disabled. Previous inquiry shows VDE asymmetry characterized by SOL current fraction and geometric parameters of tokamak plasmas. We note that, of plasmas displaced by the PCS, short displacement time scales near the limit of the PCS temporal control appear to result in larger n=1/n=2 asymmetries. Work supported under USDOE Cooperative Agreement DE-FC02-04ER54698 and DE-FG02-04ER54761.

  4. [Vertical fractures: apropos of 2 clinical cases]. (United States)

    Félix Mañes Ferrer, J; Micò Muñoz, P; Sánchez Cortés, J L; Paricio Martín, J J; Miñana Laliga, R


    The aim of the study is to present a clinical review of the vertical root fractures. Two clinical cases are presented to demonstrates the criteria for obtaining a correct diagnosis of vertical root fractures.

  5. Determinations of vertical stroke V{sub cb} vertical stroke and vertical stroke V{sub ub} vertical stroke from baryonic Λ{sub b} decays

    Energy Technology Data Exchange (ETDEWEB)

    Hsiao, Y.K. [Shanxi Normal University, School of Physics and Information Engineering, Linfen (China); National Tsing Hua University, Department of Physics, Hsinchu (China); Geng, C.Q. [Shanxi Normal University, School of Physics and Information Engineering, Linfen (China); National Tsing Hua University, Department of Physics, Hsinchu (China); Hunan Normal University, Synergetic Innovation Center for Quantum Effects and Applications (SICQEA), Changsha (China)


    We present the first attempt to extract vertical stroke V{sub cb} vertical stroke from the Λ{sub b} → Λ{sub c}{sup +}l anti ν{sub l} decay without relying on vertical stroke V{sub ub} vertical stroke inputs from the B meson decays. Meanwhile, the hadronic Λ{sub b} → Λ{sub c}M{sub (c)} decays with M = (π{sup -},K{sup -}) and M{sub c} =(D{sup -},D{sup -}{sub s}) measured with high precisions are involved in the extraction. Explicitly, we find that vertical stroke V{sub cb} vertical stroke =(44.6 ± 3.2) x 10{sup -3}, agreeing with the value of (42.11 ± 0.74) x 10{sup -3} from the inclusive B → X{sub c}l anti ν{sub l} decays. Furthermore, based on the most recent ratio of vertical stroke V{sub ub} vertical stroke / vertical stroke V{sub cb} vertical stroke from the exclusive modes, we obtain vertical stroke V{sub ub} vertical stroke = (4.3 ± 0.4) x 10{sup -3}, which is close to the value of (4.49 ± 0.24) x 10{sup -3} from the inclusive B → X{sub u}l anti ν{sub l} decays. We conclude that our determinations of vertical stroke V{sub cb} vertical stroke and vertical stroke V{sub ub} vertical stroke favor the corresponding inclusive extractions in the B decays. (orig.)

  6. Natural convection heat transfer along vertical rectangular ducts

    Energy Technology Data Exchange (ETDEWEB)

    Ali, M. [King Saud University, Mechanical Engineering Department, Riyadh (Saudi Arabia)


    Experimental investigations have been reported on steady state natural convection from the outer surface of vertical rectangular and square ducts in air. Seven ducts have been used; three of them have a rectangular cross section and the rest have square cross section. The ducts are heated using internal constant heat flux heating elements. The temperatures along the vertical surface and the peripheral directions of the duct wall are measured. Axial (perimeter averaged) heat transfer coefficients along the side of each duct are obtained for laminar and transition to turbulent regimes of natural convection heat transfer. Axial (perimeter averaged) Nusselt numbers are evaluated and correlated using the modified Rayleigh numbers for laminar and transition regime using the vertical axial distance as a characteristic length. Critical values of the modified Rayleigh numbers are obtained for transition to turbulent. Furthermore, total overall averaged Nusselt numbers are correlated with the modified Rayleigh numbers and the area ratio for the laminar regimes. The local axial (perimeter averaged) heat transfer coefficients are observed to decrease in the laminar region and increase in the transition region. Laminar regimes are obtained at the lower half of the ducts and its chance to appear decreases as the heat flux increases. (orig.)

  7. A Nature-Based Social-Emotional Approach to Supporting Young Children's Holistic Development in Classrooms with and without Walls: The Social-Emotional and Environmental Education Development (SEED) Framework (United States)

    Carter, Deborah


    This paper describes a nature-based social-emotional approach to supporting young children's holistic development that can be applied in a range of early childhood settings from forest kindergartens and nature-based preschools to more traditional center-based early childhood programs. "The Social-Emotional and Environmental Education…

  8. Iron(II) tetrakis(diaquaplatinum)octacarboxyphthalocyanine supported on multi-walled carbon nanotube platform: an efficient functional material for enhancing electron transfer kinetics and electrocatalytic oxidation of formic acid

    CSIR Research Space (South Africa)

    Mamuru, SA


    Full Text Available the oxidation of formic acid have been explored on a graphite electrode platform pre-modified with or without acid-functionalised multiwalled carbon nanotubes (MWCNTs). We prove that PtFeOCPc supported on a MWCNT platform (MWCNT–PtFeOCPc) exhibits enhanced...

  9. Bilateral vertical segmental distraction in a patient with bilateral cleft of lip, alveolus, and palate. (United States)

    Pichelmayer, Margit; Zemann, Wolfgang


    In cases of bilateral clefts of lip and palate there is often a vertical and transversal deficit of the cleft segments. Ideally these problems can be solved orthodontically. In severe cases there is a need of surgical support. Distraction osteogenesis allows the correction of transversal, horizontal, and vertical deficits. A case of a 13-year-old girl with a bilateral cleft of lip and palate is presented. The patient had a severe deficit of the distal cleft segments concerning the vertical and transversal dimension. Osteotomy of the segments was performed and a vertical distraction followed by a transpalatal distraction procedure was used to correct the discrepancies.

  10. Moving wall, continuous flow electronphoresis apparatus (United States)

    Rhodes, Percy H. (Inventor); Snyder, Robert S. (Inventor)


    This invention relates generally to electrophoresis devices and more particularly to a moving wall, continuous flow device in which an electrophoresis chamber is angularly positionable with respect to the direction of moving belt walls. A frame with an electrophoresis chamber is rotatably supported between two synchronously driven belt walls. This allows the chamber to be angularly positionable with respect to the direction of belt travel, which compensates for electroosmotic flow within the electrophoresis chamber. Injection of a buffer solution via an opening and a homogenous sample stream via another opening is performed at the end of a chamber, and collection of buffer and the fractionated species particles is done by a conventional collection array at an opposite end of the chamber. Belts are driven at a rate which exactly matches the flow of buffer and sample through the chamber, which entrains the buffer to behave as a rigid electrophoretic medium, eliminating flow distortions (Poiseuille effect). Additionally, belt material for each belt is stored at one end of the device and is taken up by drive wheels at an opposite end. The novelty of this invention particularly lies in the electrophoresis chamber being angularly positionable between two moving belt walls in order to compensate for electroosmotic flow. Additionally, new belt material is continuously exposed within the chamber, minimizing flow distortion due to contamination of the belt material by the sample.

  11. ?Vertical Sextants give Good Sights? (United States)

    Richey, Michael

    Mark Dixon suggests (Forum, Vol. 50, 137) that nobody thus far has attempted to quantify the errors from tilt that arise while observing with the marine sextant. The issue in fact, with the related problem of what exactly is the axis about which the sextant is rotated whilst being (to define the vertical), was the subject of a lively controversy in the first two volumes of this Journal some fifty years ago. Since the consensus of opinion seems to have been that the maximum error does not necessarily occur at 45 degrees, whereas Dixon's table suggests that it does, some reiteration of the arguments may be in order.



    Lama Ramirez, R.; Universidad Nacional Mayor De San Marcos Facultad de Química e Ingeniería Química Departamento de Operaciones Unitarias Av. Venezuela cdra. 34 sin, Lima - Perú; Condorhuamán Ccorimanya, C.; Universidad Nacional Mayor De San Marcos Facultad de Química e Ingeniería Química Departamento de Operaciones Unitarias Av. Venezuela cdra. 34 sin, Lima - Perú


    lt has been studied the batch sedimentation of aqueous suspensions of precipitated calcium carbonate, barium sulphate and lead oxide , in vertical thickeners of rectangular and circular cross sectional area. Suspensions vary in concentration between 19.4 and 617.9 g/I and the rate of sedimentation obtained between 0.008 and 7.70 cm/min. The effect of the specific gravity of the solid on the rate of sedimentation is the same for all the suspensions, that is, the greater the value of the specif...

  13. Binocular responses and vertical strabismus

    Directory of Open Access Journals (Sweden)

    Risović Dušica


    Full Text Available Background/Aim. Elevation in adduction is the most common pattern of vertical strabismus, and it is mostly treated with surgery. The results of weaking of inferior oblique muscle are very changeable. The aim of this study was to evaluate binocular vision using sensory tests before and one and six months after the surgery. Methods. A total of 79 children were divided in two groups: the first, with inferior oblique muscle of overaction (n = 52, and the second with dissociated vertical deviation (DVD, and primary inferior oblique muscle overaction (n = 27. We tested them by polaroid mirror test (PMT, Worth test at distance and near, fusion amplitudes on sinoptofore, Lang I stereo test and Wirt-Titmus stereo test. We examined our patients before and two times after the surgery for vertical strabismus. Results. Foveal suppression in the group I was found in 60.5% of the patients before, and in 56.4% after the surgery. In group II Foveal suppression was detected in 64.7% of the patients before, but in 55.6% 6 months after the surgery with PMT. Worth test revealed suppression in 23.5% of the patients before, and in 40.7% after the vertical muscle surgery. Parafoveal fussion persisted in about 1/3 of the patients before the surgery, and their amplitudes were a little larger after the surgery in the group I patients. Lang I stereo test was negative in 53.9% before and 51.9% after the surgery in the group I, and in 48.2% of the patients before and after the surgery in the group II patients. Wirt-Titmus stereo test was negative in 74.5% of the patients before and in 72.9% after the surgery in the group I, but in the group II it was negative in 70.8% before and in 68.0% of the patients 6 months after the surgery. Conclusion. Binocular responses were found after surgery in 65.7% of the patients the group I and in 55.6% patients the group II. There was no significant difference between these two groups, but binocular responses were more often in the patients

  14. Strengthening of Shear Walls

    DEFF Research Database (Denmark)

    Hansen, Christian Skodborg

    The theory for concrete structures strengthened with fiber reinforced polymer materials has been developing for approximately two decades, and there are at the present time numerous guidelines covering strengthening of many commonly encountered structural building elements. Strengthening of in......-plane loaded walls and disks is however not included in any guidelines, and only a small fraction of scientists have initiated research within this topic. Furthermore, studies of the principal behavior and response of a strengthened disk has not yet been investigated satisfactorily, and this is the principal...... that describes a unit width strip of a strengthened disk. The unit width strip is named a strengthened concrete tension member and contains a single tensile crack and four debonding cracks. Analysis of the member results in closed form expressions for the load-crack opening relationship. Further analysis...

  15. Great Wall of China (United States)


    This ASTER sub-image covers a 12 x 12 km area in northern Shanxi Province, China, and was acquired January 9, 2001. The low sun angle, and light snow cover highlight a section of the Great Wall, visible as a black line running diagonally through the image from lower left to upper right. The Great Wall is over 2000 years old and was built over a period of 1000 years. Stretching 4500 miles from Korea to the Gobi Desert it was first built to protect China from marauders from the north.This image is located at 40.2 degrees north latitude and 112.8 degrees east longitude.Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, Calif., is the U.S. Science team leader; Moshe Pniel of JPL is the project manager. ASTER is the only high resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface.The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats, monitoring potentially active volcanoes, identifying crop stress, determining cloud morphology and physical properties, wetlands Evaluation, thermal pollution monitoring, coral reef degradation, surface temperature mapping of soils and geology, and measuring surface

  16. Cell wall evolution and diversity

    Directory of Open Access Journals (Sweden)

    Jonatan Ulrik Fangel


    Full Text Available Plant cell walls display a considerable degree of diversity in their compositions and molecular architectures. In some cases the functional significance of a particular cell wall type appears to be easy to discern: secondary cells walls are often heavy reinforced with lignin that provides the required durability; the thin cell walls of pollen tubes have particular compositions that enable their tip growth; lupin seed cell walls are characteristically thickened with galactan used as a storage polysaccharide. However, more frequently the evolutionary mechanisms and selection pressures that underpin cell wall diversity and evolution are unclear. The rapidly increasing availability of transcriptome and genome data sets, development of high-throughput methods for cell wall analyses, and expansion of molecular probe sets, are providing new insights into the diversity and occurrence of cell wall polysaccharides and associated biosynthetic genes. Such research is important for refining our understanding of some of the fundamental processes that enabled plants to colonise land and subsequently radiate so comprehensively. The study of cell wall structural diversity is also an important aspect of the industrial utilization of global polysaccharide bio-resources.

  17. External Insulation of Masonry Walls and Wood Framed Walls

    Energy Technology Data Exchange (ETDEWEB)

    Baker, P. [Building Science Corporation, Somerville, MA (United States)


    The use of exterior insulation on a building is an accepted and effective means to increase the overall thermal resistance of the assembly that also has other advantages of improved water management and often increased air tightness of building assemblies. For thin layers of insulation (1” to 1 ½”), the cladding can typically be attached directly through the insulation back to the structure. For thicker insulation layers, furring strips have been added as a cladding attachment location. This approach has been used in the past on numerous Building America test homes and communities (both new and retrofit applications), and has been proven to be an effective and durable means to provide cladding attachment. However, the lack of engineering data has been a problem for many designers, contractors, and code officials. This research project developed baseline engineering analysis to support the installation of thick layers of exterior insulation on existing masonry and frame walls. Furthermore, water management details necessary to integrate windows, doors, decks, balconies and roofs were created to provide guidance on the integration of exterior insulation strategies with other enclosure elements.

  18. External Insulation of Masonry Walls and Wood Framed Walls

    Energy Technology Data Exchange (ETDEWEB)

    Baker, P.


    The use of exterior insulation on a building is an accepted and effective means to increase the overall thermal resistance of the assembly that also has other advantages of improved water management and often increased air tightness of building assemblies. For thin layers of insulation (1" to 1 1/2"), the cladding can typically be attached directly through the insulation back to the structure. For thicker insulation layers, furring strips have been added as a cladding attachment location. This approach has been used in the past on numerous Building America test homes and communities (both new and retrofit applications), and has been proven to be an effective and durable means to provide cladding attachment. However, the lack of engineering data has been a problem for many designers, contractors, and code officials. This research project developed baseline engineering analysis to support the installation of thick layers of exterior insulation on existing masonry and frame walls. Furthermore, water management details necessary to integrate windows, doors, decks, balconies and roofs were created to provide guidance on the integration of exterior insulation strategies with other enclosure elements.

  19. Free surface entropic lattice Boltzmann simulations of film condensation on vertical hydrophilic plates

    DEFF Research Database (Denmark)

    Hygum, Morten Arnfeldt; Karlin, Iliya; Popok, Vladimir


    A model for vapor condensation on vertical hydrophilic surfaces is developed using the entropic lattice Boltzmann method extended with a free surface formulation of the evaporation–condensation problem. The model is validated with the steady liquid film formation on a flat vertical wall....... It is shown that the model is in a good agreement with the classical Nusselt equations for the laminar flow regime. Comparisons of the present model with other empirical models also demonstrate good agreement beyond the laminar regime. This allows the film condensation modeling at high film Reynolds numbers...

  20. Vertically stacked nanocellulose tactile sensor. (United States)

    Jung, Minhyun; Kim, Kyungkwan; Kim, Bumjin; Lee, Kwang-Jae; Kang, Jae-Wook; Jeon, Sanghun


    Paper-based electronic devices are attracting considerable attention, because the paper platform has unique attributes such as flexibility and eco-friendliness. Here we report on what is claimed to be the firstly fully integrated vertically-stacked nanocellulose-based tactile sensor, which is capable of simultaneously sensing temperature and pressure. The pressure and temperature sensors are operated using different principles and are stacked vertically, thereby minimizing the interference effect. For the pressure sensor, which utilizes the piezoresistance principle under pressure, the conducting electrode was inkjet printed on the TEMPO-oxidized-nanocellulose patterned with micro-sized pyramids, and the counter electrode was placed on the nanocellulose film. The pressure sensor has a high sensitivity over a wide range (500 Pa-3 kPa) and a high durability of 10(4) loading/unloading cycles. The temperature sensor combines various materials such as poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS), silver nanoparticles (AgNPs) and carbon nanotubes (CNTs) to form a thermocouple on the upper nanocellulose layer. The thermoelectric-based temperature sensors generate a thermoelectric voltage output of 1.7 mV for a temperature difference of 125 K. Our 5 × 5 tactile sensor arrays show a fast response, negligible interference, and durable sensing performance.

  1. FDNS code to predict wall heat fluxes or wall temperatures in rocket nozzles (United States)

    Karr, Gerald R.


    This report summarizes the findings on the NASA contract NAG8-212, Task No. 3. The overall project consists of three tasks, all of which have been successfully completed. In addition, some supporting supplemental work, not required by the contract, has been performed and is documented herein. Task 1 involved the modification of the wall functions in the code FDNS to use a Reynolds Analogy-based method. Task 2 involved the verification of the code against experimentally available data. The data chosen for comparison was from an experiment involving the injection of helium from a wall jet. Results obtained in completing this task also show the sensitivity of the FDNS code to unknown conditions at the injection slot. Task 3 required computation of the flow of hot exhaust gases through the P&W 40K subscale nozzle. Computations were performed both with and without film coolant injection. The FDNS program tends to overpredict heat fluxes, but, with suitable modeling of backside cooling, may give reasonable wall temperature predictions. For film cooling in the P&W 40K calorimeter subscale nozzle, the average wall temperature is reduced from 1750 R to about 1050 R by the film cooling. The average wall heat flux is reduced by a factor of three.

  2. Deletion of hypothetical wall teichoic acid ligases in Staphylococcus aureus activates the cell wall stress response. (United States)

    Dengler, Vanina; Meier, Patricia Stutzmann; Heusser, Ronald; Kupferschmied, Peter; Fazekas, Judit; Friebe, Sarah; Staufer, Sibylle Burger; Majcherczyk, Paul A; Moreillon, Philippe; Berger-Bächi, Brigitte; McCallum, Nadine


    The Staphylococcus aureus cell wall stress stimulon (CWSS) is activated by cell envelope-targeting antibiotics or depletion of essential cell wall biosynthesis enzymes. The functionally uncharacterized S. aureus LytR-CpsA-Psr (LCP) proteins, MsrR, SA0908 and SA2103, all belong to the CWSS. Although not essential, deletion of all three LCP proteins severely impairs cell division. We show here that VraSR-dependent CWSS expression was up to 250-fold higher in single, double and triple LCP mutants than in wild type S. aureus in the absence of external stress. The LCP triple mutant was virtually depleted of wall teichoic acids (WTA), which could be restored to different degrees by any of the single LCP proteins. Subinhibitory concentrations of tunicamycin, which inhibits the first WTA synthesis enzyme TarO (TagO), could partially complement the severe growth defect of the LCP triple mutant. Both of the latter findings support a role for S. aureus LCP proteins in late WTA synthesis, as in Bacillus subtilis where LCP proteins were recently proposed to transfer WTA from lipid carriers to the cell wall peptidoglycan. Intrinsic activation of the CWSS upon LCP deletion and the fact that LCP proteins were essential for WTA-loading of the cell wall, highlight their important role(s) in S. aureus cell envelope biogenesis. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  3. Neonatal Anaplasma platys infection in puppies: Further evidence for possible vertical transmission

    Czech Academy of Sciences Publication Activity Database

    Matei, I.A.; Stuen, S.; Modrý, David; Degan, A.; D'Amico, G.; Mihalca, A. D.


    Roč. 219, 1 January (2017), s. 40-41 ISSN 1090-0233 Institutional support: RVO:60077344 Keywords : Anaplasma platys * canine * vertical transmission Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 1.802, year: 2016

  4. Validated Design and Analysis Tool for Small Vertical-Lift Unmanned Air Vehicle Noise Prediction Project (United States)

    National Aeronautics and Space Administration — A procedure and supporting computer code for the prediction of noise that radiates from small, vertical lift UAV aircraft is proposed. The resulting building block...

  5. Vertical Integration of Hospitals and Physicians: Economic Theory and Empirical Evidence on Spending and Quality. (United States)

    Post, Brady; Buchmueller, Tom; Ryan, Andrew M


    Hospital-physician vertical integration is on the rise. While increased efficiencies may be possible, emerging research raises concerns about anticompetitive behavior, spending increases, and uncertain effects on quality. In this review, we bring together several of the key theories of vertical integration that exist in the neoclassical and institutional economics literatures and apply these theories to the hospital-physician relationship. We also conduct a literature review of the effects of vertical integration on prices, spending, and quality in the growing body of evidence ( n = 15) to evaluate which of these frameworks have the strongest empirical support. We find some support for vertical foreclosure as a framework for explaining the observed results. We suggest a conceptual model and identify directions for future research. Based on our analysis, we conclude that vertical integration poses a threat to the affordability of health services and merits special attention from policymakers and antitrust authorities.

  6. Occupy Wall Street: Examining a Current Event as It Happens (United States)

    Bellows, Elizabeth; Bauml, Michele; Field, Sherry; Ledbetter, Mary


    On September 17, 2011 (Constitution Day), Occupy Wall Street began as a protest movement when approximately 2,000 supporters assembled in lower Manhattan's Zuccotti Park. The group's concerns focused on the corporate role in the current financial crisis and economic inequality. Rhetoric both in support of and against the protest began to flood the…

  7. Cells positioning using magnetic domain walls of ferromagnetic zigzag thin film (United States)

    Huang, Hao-Ting; Chen, Chia-Yi; Lai, Mei-Feng


    Magnetic cell positioning is demonstrated by controlling the magnetic domain walls in ferromagnetic zigzag thin films. Magnetophoresis experiment is performed to determine the number of magnetic nanoparticles that enter the cells by endocytosis. It is observed that in the zigzag structure with larger wavelength the magnetic cells are better aligned at the vertices.

  8. An approximate method for lateral stability analysis of wall-frame ...

    Indian Academy of Sciences (India)

    effect of shear deformations of walls has been taken into consideration and incorporated in the formulation of the governing equations. The following assumptions are made in this study; the behaviour of the material is linear elastic, the floor slabs of the building have great in-plane and small out-of-plane stiffness, the vertical ...

  9. Plasticity Approach to HSC Shear Wall Design

    DEFF Research Database (Denmark)

    Liu, Lunying; Nielsen, Mogens Peter


    The paper describes a simple theory for determining the ultimate strength of shear walls. It is based on application of the theory of perfectly plastic materials. When applied to concrete the theoretical solutions must be modified by inserting into the solutions a reduced compressive strength...... to 140 MPa and reinforcement yield strengths up to 1420 MPa. The work was carried out as a Ph.D. study by the first author, the second author supervising the study.Keywords: shear wall, plasticity, strut and tie, load-carrying capacity, concrete, reinforcement....... of concrete. The reduced strength is named the effective strength. The paper describes simple lower bound solutions. They consist of pure strut action or strut action combined with diagonal compression fields outside the struts. Near moment maximum and near supports the stress fields are modified to save...

  10. Near Wall Turbulence: an experimental view (United States)

    Stanislas, Michel


    The aim of this presentation is to summarize the understanding of the near wall turbulence phenomena obtained at Laboratoire de Mécanique de Lille using both hot wire anemometry and PIV. A wind tunnel was built in 1993 specifically designed for these two measurement techniques and aimed at large Reynolds numbers. Several experiments were performed since then in the frame of different PhDs and European projects, all aimed at evidencing turbulence organization in this region. These have fully benefited of the extraordinary development of PIV in that time frame, which has allowed entering visually and quantitatively inside the complex spatial and temporal structure of near wall turbulence. The presentation will try to emphasize the benefit of this approach in terms of understanding and modelling, illustrated by some representative results obtained. M. Stanislas particularly acknowledges the financial support of Region Nord Pas de Calais, unmissing during 25 years.

  11. Occupy Wall Street




    В статье рассматривается организованная антипотребительскими сообществами и направленная против негативных форм глобализации акция «Occupy Wall Street». Движение возникло осенью 2011 г. в США и стремительно распространилось по всему миру. Акции в поддержку движения были проведены еще в 82 странах. Автор, исследуя причины возникновения движения и источники его финансирования, приходит к выводу, что проект «Occupy Wall Street» может быть очередной уловкой глобалистов, цель которой «обезвредить»...

  12. Model Tests on the Retaining Walls Constructed from Geobags Filled with Construction Waste

    Directory of Open Access Journals (Sweden)

    Hua Wen


    Full Text Available Geobag retaining wall using construction waste is a new flexible supporting structure, and the usage of construction waste to fill geobags can facilitate the construction recycling. In this paper, model tests were performed on geobag retaining wall using construction waste. The investigation was concentrated on the slope top settlement, the distribution characteristics of the earth pressures on retaining walls and horizontal wall displacements, and slope failure modes. The results indicated that the ultimate loads that the slope tops with retaining walls could bear were 87.5%~125% higher than that of the slope top without retaining walls. The ultimate loading of strengthened slopes with different slope ratios from 1 : 0.75 to 1 : 0.25 could be reduced by 11.8% to 29.4%. The horizontal displacements of the retaining walls constructed from geobags were distributed in a drum shape, with the greatest horizontal displacements occurring about 1/3~1/2 of the wall height away from the bottom of the wall. As the slope ratio increased, the failure of the slope soil supported by geobag retaining wall using construction waste changed from sliding to sliding-toppling (dominated by sliding and then to toppling-sliding (dominated by toppling. The range of 1/3~1/2 of wall height is the weak part of the retaining walls, which should be strengthened with certain measures during the process of design and construction.

  13. Control of Wall Mounting Robot

    DEFF Research Database (Denmark)

    Sloth, Christoffer; Pedersen, Rasmus


    This paper presents a method for designing controllers for trajectory tracking with actuator constraints. In particular, we consider a joystick-controlled wall mounting robot called WallMo. In contrast to previous works, a model-free approach is taken to the control problem, where the path...

  14. Moisture Research - Optimizing Wall Assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Arena, L.; Mantha, P.


    The Consortium for Advanced Residential Buildings (CARB) evaluated several different configurations of wall assemblies to determine the accuracy of moisture modeling and make recommendations to ensure durable, efficient assemblies. WUFI and THERM were used to model the hygrothermal and heat transfer characteristics of these walls.

  15. Bacterial cell-wall recycling (United States)

    Johnson, Jarrod W.; Fisher, Jed F.; Mobashery, Shahriar


    Many Gram-negative and Gram-positive bacteria recycle a significant proportion of the peptidoglycan components of their cell walls during their growth and septation. In many—and quite possibly all—bacteria, the peptidoglycan fragments are recovered and recycled. While cell-wall recycling is beneficial for the recovery of resources, it also serves as a mechanism to detect cell-wall–targeting antibiotics and to regulate resistance mechanisms. In several Gram-negative pathogens, anhydro-MurNAc-peptide cell-wall fragments regulate AmpC β-lactamase induction. In some Gram-positive organisms, short peptides derived from the cell wall regulate the induction of both β-lactamase and β-lactam-resistant penicillin-binding proteins. The involvement of peptidoglycan recycling with resistance regulation suggests that inhibitors of the enzymes involved in the recycling might synergize with cell-wall-targeted antibiotics. Indeed, such inhibitors improve the potency of β-lactams in vitro against inducible AmpC β-lactamase-producing bacteria. We describe the key steps of cell-wall remodeling and recycling, the regulation of resistance mechanisms by cell-wall recycling, and recent advances toward the discovery of cell-wall recycling inhibitors. PMID:23163477

  16. Ultrasonography of chest wall lesion

    Energy Technology Data Exchange (ETDEWEB)

    Park, Cheol Min; Kim, C. H.; Cha, I. H.; Chung, K. B.; Ser, W. H.; Choi, Y. H. [Seoul National University College of Medicine, Seoul (Korea, Republic of)


    Thirty-one patients with chest wall diseases were studied with ultrasound to evaluate its role in chest wall lesions. There were eight infectious conditions, 9 benign tumors, 11 malignant lesions and 3 miscellaneous cases. Diffuse chest wall thickening with heterogeneous echogenicity and obliteration of subcutaneous fat layer are findings of acute infection. In cases of tuberculous smpyema necessitates, pleural abnormality extended to the chest wall through intercostal space. Benign tumors were well demarcated, except in 4 cases of lipoma/lipomatosis. Malignant lesions showed irregular soft tissue masses, bone destruction, pleural effusion and subcutaneous invasion. Multiple enlarged lymph nodes were also shown. Ultrasound can demonstrate te internal structure, extent, depth and associated findings such as pleural effusion, bone destruction and peripheral lung involvement. Ultrasound is not only safe, non-invasive and an effective diagnostic imaging modality for chest wall disease, but can also guide aspiration or biopsy for pathologic diagnosis

  17. Capillary holdup between vertical spheres

    Directory of Open Access Journals (Sweden)

    S. Zeinali Heris


    Full Text Available The maximum volume of liquid bridge left between two vertically mounted spherical particles has been theoretically determined and experimentally measured. As the gravitational effect has not been neglected in the theoretical model, the liquid interface profile is nonsymmetrical around the X-axis. Symmetry in the interface profile only occurs when either the particle size ratio or the gravitational force becomes zero. In this paper, some equations are derived as a function of the spheres' sizes, gap width, liquid density, surface tension and body force (gravity/centrifugal to estimate the maximum amount of liquid that can be held between the two solid spheres. Then a comparison is made between the result based on these equations and several experimental results.

  18. Association Mapping of Cell Wall Synthesis Regulatory Genes and Cell Wall Quality in Switchgrass

    Energy Technology Data Exchange (ETDEWEB)

    Bartley, Laura [Univ. of Oklahoma, Norman, OK (United States). Dept. of Microbiology and Plant Biology; Wu, Y. [Oklahoma State Univ., Stillwater, OK (United States); Zhu, L. [Oklahoma State Univ., Stillwater, OK (United States); Brummer, E. C. [Noble Foundation, Ardmore, OK (United States); Saha, M. [Noble Foundation, Ardmore, OK (United States)


    transcription factors from the rice gene network. Eight of fifteen (53%) of these have not previously been examined for this function. Some of these may represent novel grass-diverged cell wall regulators, while others are likely to have this function across angiosperms. A parallel effort of this project to expand knowledge of enzymes that have evolved to function in grass cell wall synthesis, revealed that a grass-diverged enzyme in rice, OsAT5, ferulates monolignols that are naturally incorporated into grass cell walls. This finding opens potential natural selection avenues for improving biomass composition for downstream processing by weak base pretreatment. Thus, this project has significantly expanded knowledge of cell wall synthesis and regulation in rice, information that can be used in reverse genetics and synthetic biology approaches to re-engineer cell walls for improved production of biofuel and high-value products. To lay the foundation for translating these results directly for switchgrass improvement, the project employed a comparative phylogenetic analysis of the major group of cell wall transcription factors that have been found to function in cell wall regulation, the R2R3 MYBs. This analysis concluded that known cell wall regulators are largely conserved across switchgrass, rice, maize, poplar, and Arabidopsis. This interpretation is also largely consistent with the gene network analysis described above, though both approaches provide evidence that some co-orthologs of Arabidopsis regulators have diminished or increased in importance based on gene expression patterns. Also, several clades containing dicot cell wall regulators have expanded, consistent with the evolution of new cell wall regulators. This latter result is supported by functional analysis of the R2R3 MYB protein SWAM1 in a collaboration between this project and the DOE-funded group of Dr. S. Hazen at the University of

  19. Vertical jump coordination: fatigue effects. (United States)

    Rodacki, André Luiz Felix; Fowler, Neil E; Bennett, Simon J


    The aim of this study was to investigate the segmental coordination of vertical jumps under fatigue of the knee extensor and flexor muscles. Eleven healthy and active subjects performed maximal vertical jumps with and without fatigue, which was imposed by requesting the subjects to extend/flex their knees continuously in a weight machine, until they could not lift a load corresponding to approximately 50% of their body weight. Knee extensor and flexor isokinetic peak torques were also measured before and after fatigue. Video, ground reaction forces, and electromyographic data were collected simultaneously and used to provide several variables of the jumps. Fatiguing the knee flexor muscles did not reduce the height of the jumps or induce changes in the kinematic, kinetic, and electromyographic profiles. Knee extensor fatigue caused the subjects to adjust several variables of the movement, in which the peak joint angular velocity, peak joint net moment, and power around the knee were reduced and occurred earlier in comparison with the nonfatigued jumps. The electromyographic data analyses indicated that the countermovement jumps were performed similarly, i.e., a single strategy was used, irrespective of which muscle group (extensor or flexors) or the changes imposed on the muscle force-generating characteristics (fatigue or nonfatigue). The subjects executed the movements as if they scaled a robust template motor program, which guided the movement execution in all jump conditions. It was speculated that training programs designed to improve jump height performance should avoid severe fatigue levels, which may cause the subjects to learn and adopt a nonoptimal and nonspecific coordination solution. It was suggested that the neural input used in the fatigued condition did not constitute an optimal solution and may have played a role in decreasing maximal jump height achievement.

  20. Dry wall Kras 2011

    Directory of Open Access Journals (Sweden)

    Domen Zupančič


    Full Text Available Despite the modesty of hiska, they show a simple understanding of corbelling technique. One could say they are all examples of human landscape cultivation. Although there is no evident common line when comparing all types of hiska, the cunning eye may observe one shared feature: the positioning of the entrance. More or less all the documented shelters have south or south-western facing entrances. The burja is a cold northerly wind; from the south (Adriatic Sea the winds are warmer. When resting, the setting sun is taken as a sign of the ending of the working day and a reward for the whole day’s efforts. Entrances are the only openings to these structures, and they should serve as well as possible - to watch over the crops, to wait when hunting, to enjoy the calm of evening light, to breathe the sea wind.The syntax of the architectural language of layering stone and shaping the pattern of the landscape remain an inventive realisation of spatial ideas from the past until today. Not only ideas of shaping space - these ideas are basic interventions in the natural habitat which contribute to survival. Culture and an awareness of its values are the origins of local development and reasonable heritage preservation. The next step are tutorial days with workshops on how to build dry stone structures, walls and other stone architecture, as the DSWA organisation in the UK is doing.

  1. Channel Wall Landslides (United States)


    [figure removed for brevity, see original site] The multiple landslides in this VIS image occur along a steep channel wall. Note the large impact crater in the context image. The formation of the crater may have initially weakened that area of the surface prior to channel formation. Image information: VIS instrument. Latitude -2.7, Longitude 324.8 East (35.2 West). 19 meter/pixel resolution. Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time. NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  2. Evaluation of Steel Shear Walls Behavior with Sinusoidal and Trapezoidal Corrugated Plates

    Directory of Open Access Journals (Sweden)

    Emad Hosseinpour


    Full Text Available Reinforcement of structures aims to control the input energy of unnatural and natural forces. In the past four decades, steel shear walls are utilized in huge constructions in some seismic countries such as Japan, United States, and Canada to lessen the risk of destructive forces. The steel shear walls are divided into two types: unstiffened and stiffened. In the former, a series of plates (sinusoidal and trapezoidal corrugated with light thickness are used that have the postbuckling field property under overall buckling. In the latter, steel profile belt series are employed as stiffeners with different arrangement: horizontal, vertical, or diagonal in one side or both sides of wall. In the unstiffened walls, increasing the thickness causes an increase in the wall capacity under large forces in tall structures. In the stiffened walls, joining the stiffeners to the wall is costly and time consuming. The ANSYS software was used to analyze the different models of unstiffened one-story steel walls with sinusoidal and trapezoidal corrugated plates under lateral load. The obtained results demonstrated that, in the walls with the same dimensions, the trapezoidal corrugated plates showed higher ductility and ultimate bearing compared to the sinusoidal corrugated plates.

  3. Analysis of the flow structure and heat transfer in a vertical mantle heat exchanger

    DEFF Research Database (Denmark)

    Knudsen, Søren; Morrison, GL; Behnia, M


    The flow structure inside the inner tank and inside the mantle of a vertical mantle heat exchanger was investigated using a full-scale tank designed to facilitate flow visualisation. The flow structure and velocities in the inner tank and in the mantle were measured using a Particle Image...... Velocimetry (PIV) system. A Computational Fluid Dynamics (CFD) model of the vertical mantle heat exchanger was also developed for a detailed evaluation of the heat flux at the mantle wall and at the tank wall. The flow structure was evaluated for both high and low temperature incoming flows and for both...... initially mixed and initially stratified inner tank and mantle. The analysis of the heat transfer showed that the flow in the mantle near the inlet is mixed convection flow and that the heat transfer is dependent on the mantle inlet temperature relative to the core tank temperature at the mantle level. (C...

  4. HPM-Pade Method on Natural Convection of Darcian Fluid about a Vertical Full Cone Embedded in Porous Media

    DEFF Research Database (Denmark)

    Bararnia, H.; Ghasemi, E.; Soleimanikutanaei, Soheil


    In this paper, fluid flow and heat transfer of a vertical full cone embedded in porous media have been studied. A similarity solution for a full cone subjected to wall temperature boundary conditions gives us a nonlinear ordinary differential equation (ODE), which has been solved through...

  5. Applicability of tungsten/EUROFER blanket module for the DEMO first wall (United States)

    Igitkhanov, Yu.; Bazylev, B.; Landman, I.; Boccaccini, L.


    In this paper we analyse a sandwich-type blanket configuration of W/EUROFER for DEMO first wall under steady-state normal operation and off-normal conditions, such as vertical displacements and runaway electrons. The heat deposition and consequent erosion of the tungsten armour is modelled under condition of helium cooling of the first wall blanket module and by taking into account the conversion of the magnetic energy stored in the runaway electron current into heat through the ohmic dissipation of the return current induced in the metallic armour structure. It is shown that under steady-state DEMO operation the first wall sandwich type module will tolerate heat loads up to ˜14 MW/m2. It will also sustain the off-normal events, apart from the hot vertical displacement events, which will melt the tungsten armour surface.

  6. Applicability of tungsten/EUROFER blanket module for the DEMO first wall

    Energy Technology Data Exchange (ETDEWEB)

    Igitkhanov, Yu., E-mail: [Karlsruhe Institute of Technology, IHM, Karlsruhe (Germany); Bazylev, B.; Landman, I. [Karlsruhe Institute of Technology, IHM, Karlsruhe (Germany); Boccaccini, L. [Karlsruhe Institute of Technology, INR, Karlsruhe (Germany)


    In this paper we analyse a sandwich-type blanket configuration of W/EUROFER for DEMO first wall under steady-state normal operation and off-normal conditions, such as vertical displacements and runaway electrons. The heat deposition and consequent erosion of the tungsten armour is modelled under condition of helium cooling of the first wall blanket module and by taking into account the conversion of the magnetic energy stored in the runaway electron current into heat through the ohmic dissipation of the return current induced in the metallic armour structure. It is shown that under steady-state DEMO operation the first wall sandwich type module will tolerate heat loads up to ∼14 MW/m{sup 2}. It will also sustain the off-normal events, apart from the hot vertical displacement events, which will melt the tungsten armour surface.

  7. Single Mode Photonic Crystal Vertical Cavity Surface Emitting Lasers

    Directory of Open Access Journals (Sweden)

    Kent D. Choquette


    Full Text Available We review the design, fabrication, and performance of photonic crystal vertical cavity surface emitting lasers (VCSELs. Using a periodic pattern of etched holes in the top facet of the VCSEL, the optical cavity can be designed to support the fundamental mode only. The electrical confinement is independently defined by proton implantation or oxide confinement. By control of the refractive index and loss created by the photonic crystal, operation in the Gaussian mode can be insured, independent of the lasing wavelength.

  8. Experimental Verification of Same Simple Equilibrium Models of Masonry Shear Walls (United States)

    Radosław, Jasiński


    This paper contains theoretical fundamentals of strut and tie models, used in unreinforced horizontal shear walls. Depending on support conditions and wall loading, we can distinguish models with discrete bars when point load is applied to the wall (type I model) or with continuous bars (type II model) when load is uniformly distributed at the wall boundary. The main part of this paper compares calculated results with the own tests on horizontal shear walls made of solid brick, silicate elements and autoclaved aerated concrete. The tests were performed in Poland. The model required some modifications due to specific load and static diagram.

  9. Heat Transmission of Slab-on-Ground Industrial Floors with Vertical Perimeter Insulation


    Kocsis, Lajos


    The surface heat loss of slab-on-ground industrial floors that are vertically insulated along the footing wall (with the insulation reaching under the ground level), is closely linked with the relatively large floor area of industrial halls. To give a comprehensive heat transmission analysis, the present paper first provides an overview of the U-value requirements for such floors in Hungary and Germany. For the determination of the heat transmission coefficient of slab-on-ground floors with v...

  10. Cell wall proteomics of crops

    Directory of Open Access Journals (Sweden)

    Setsuko eKomatsu


    Full Text Available Cell wall proteins play key roles in cell structure and metabolism, cell enlargement, signal transduction, responses to environmental stress, and many other physiological events. Agricultural crops are often used for investigating stress tolerance because cultivars with differing degrees of tolerance are available. Abiotic and biotic stress factors markedly influence the geographical distribution and yields of many crop species. Crop cell wall proteomics is of particular importance for improving crop productivity, particularly under unfavorable environmental conditions. To better understand the mechanisms underlying stress response in crops, cell wall proteomic analyses are being increasingly utilized. In this review, the methods of purification and purity assays of cell wall protein fractions from crops are described, and the results of protein identification using gel-based and gel-free proteomic techniques are presented. Furthermore, protein composition of the cell walls of rice, wheat, maize and soybean are compared, and the role of cell wall proteins in crops under flooding and drought stress is discussed. This review will be useful for clarifying the role of the cell wall of crops in response to environmental stresses.

  11. On the Evaluation of Failure Probability on Monolithic Vertical Wall Breakwaters

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Sørensen, Jørgen S.; Christiani, E.


    The paper presents a level II, FORM-evaluation of the reliability against sliding of a caisson breakwater. Further, a reliability-based optimal design procedure for breakwaters exposed to multifailure mode is discussed....

  12. Spatial root distribution of plants growing in vertical media for use in living walls

    DEFF Research Database (Denmark)

    Jørgensen, Lars; Dresbøll, Dorte Bodin; Thorup-Kristensen, Kristian


    of rockwool) in transparent boxes under greenhouse conditions. Root frequency was registered and the activity of individual root systems was studied via 15N uptake and plant dry weight was measured. Results: Plants in coir had stronger root growth in all parts of the medium than plants in rockwool. Upwards...

  13. The effect of non-linear wave in front of vertical wall using bi ...

    African Journals Online (AJOL)

    From the subsequent calculation carried out, it was found that on deep water the parameter 2 tends to zero and 1 tends to , which is twice as much as the value of for the progressive waves on deep water. Moreover, for a fixed kd, this theory suggests that the non-linear effects increase while approaching the bottom, which is ...

  14. Seismic behavior and design of wall-EDD-frame systems

    Directory of Open Access Journals (Sweden)

    Oren eLavan


    Full Text Available Walls and frames have different deflection lines and, depending on the seismic mass they support, may often poses different natural periods. In many cases, wall-frame structures present an advantageous behavior. In these structures the walls and the frames are rigidly connected. Nevertheless, if the walls and the frames were not rigidly connected, an opportunity for an efficient passive control strategy would arise: Connecting the two systems by energy dissipation devices (EDDs to result in wall-EDD-frame systems. This, depending on the parameters of the system, is expected to lead to an efficient energy dissipation mechanism.This paper studies the seismic behavior of wall-EDD-frame systems in the context of retrofitting existing frame structures. The controlling non-dimensional parameters of such systems are first identified. This is followed by a rigorous and extensive parametric study that reveals the pros and cons of the new system versus wall-frame systems. The effect of the controlling parameters on the behavior of the new system are analyzed and discussed. Finally, tools are given for initial design of such retrofitting schemes. These enable both choosing the most appropriate retrofitting alternative and selecting initial values for its parameters.

  15. A Survey of Wall Climbing Robots: Recent Advances and Challenges

    Directory of Open Access Journals (Sweden)

    Shunsuke Nansai


    Full Text Available In recent decades, skyscrapers, as represented by the Burj Khalifa in Dubai and Shanghai Tower in Shanghai, have been built due to the improvements of construction technologies. Even in such newfangled skyscrapers, the façades are generally cleaned by humans. Wall climbing robots, which are capable of climbing up vertical surfaces, ceilings and roofs, are expected to replace the manual workforce in façade cleaning works, which is both hazardous and laborious work. Such tasks require these robotic platforms to possess high levels of adaptability and flexibility. This paper presents a detailed review of wall climbing robots categorizing them into six distinct classes based on the adhesive mechanism that they use. This paper concludes by expanding beyond adhesive mechanisms by discussing a set of desirable design attributes of an ideal glass façade cleaning robot towards facilitating targeted future research with clear technical goals and well-defined design trade-off boundaries.

  16. Domain walls riding the wave.

    Energy Technology Data Exchange (ETDEWEB)

    Karapetrov, G.; Novosad, V.; Materials Science Division


    Recent years have witnessed a rapid proliferation of electronic gadgets around the world. These devices are used for both communication and entertainment, and it is a fact that they account for a growing portion of household energy consumption and overall world consumption of electricity. Increasing the energy efficiency of these devices could have a far greater and immediate impact than a gradual switch to renewable energy sources. The advances in the area of spintronics are therefore very important, as gadgets are mostly comprised of memory and logic elements. Recent developments in controlled manipulation of magnetic domains in ferromagnet nanostructures have opened opportunities for novel device architectures. This new class of memories and logic gates could soon power millions of consumer electronic devices. The attractiveness of using domain-wall motion in electronics is due to its inherent reliability (no mechanical moving parts), scalability (3D scalable architectures such as in racetrack memory), and nonvolatility (retains information in the absence of power). The remaining obstacles in widespread use of 'racetrack-type' elements are the speed and the energy dissipation during the manipulation of domain walls. In their recent contribution to Physical Review Letters, Oleg Tretiakov, Yang Liu, and Artem Abanov from Texas A&M University in College Station, provide a theoretical description of domain-wall motion in nanoscale ferromagnets due to the spin-polarized currents. They find exact conditions for time-dependent resonant domain-wall movement, which could speed up the motion of domain walls while minimizing Ohmic losses. Movement of domain walls in ferromagnetic nanowires can be achieved by application of external magnetic fields or by passing a spin-polarized current through the nanowire itself. On the other hand, the readout of the domain state is done by measuring the resistance of the wire. Therefore, passing current through the

  17. Chromatography resin support (United States)

    Dobos, James G.


    An apparatus and method of using an improved chromatography resin support is disclosed. The chromatography support platform is provided by a stainless steel hollow cylinder adapted for being inserted into a chromatography column. An exterior wall of the stainless steel cylinder defines a groove for carrying therein an "O"-ring. The upper surface of the stainless steel column is covered by a fine stainless steel mesh welded to the edges of the stainless steel cylinder. When placed upon a receiving ledge defined within a chromatography column, the "O"-ring provides a fluid tight seal with the inner edge wall of the chromatography cylinder. The stainless steel mesh supports the chromatography matrix and provides a back flushable support which is economical and simple to construct.

  18. Uplift Capacity of Inclined Underreamed Piles Subjected to Vertical Load (United States)

    Rahman, Md. Akilur; Sengupta, Siddhartha


    Many offshore structures are subjected to overturning moments due to wind load, wave pressure, and ship impacts. Inclined (batter) piles are used to support such structures, and to carry the horizontal and vertical loads resulted from the overturning moments. Though studies have been done with inclined piles having no underream bulb, little information is available in the literature about estimating the uplift capacity of inclined underreamed piles. In the present study laboratory experiments have been done with vertically loaded model piles having no underream as well as with one and two underreams. The piles were positioned at angle of inclination of θ = 0°, 10°, 20°, 30° (with vertical); and placed in locally available sand under vertical uplift load. Three different pile stem diameters (D = 20, 25, and 35 mm) were used. The corresponding pile length to stem diameter (l/D) ratio were 18, 14, and 10 respectively. Experiments had been conducted with two relative different densities (45 and 70%) of sand. The failure uplift loads were obtained in each case. It had been found that for inclined piles increase in number of underream bulbs from 0 to 2 was quite effective in resisting uplift loads corresponding to piles having l/D equals to 10. The percentage decreases in uplift capacity corresponding to increase in inclination angle were more pronounced for piles with double underreams.

  19. Post-seismic relaxation process and vertical deformation following the 2008 Ms8.0 Wenchuan earthquake, China

    Directory of Open Access Journals (Sweden)

    Hao Ming


    Full Text Available The post-seismic horizontal and vertical deformations following the 2008 Ms8.0 Wenchuan earthquake are inferred from GPS and precise leveling data. The post-seismic relaxation process is measured using CPS data from campaign stations located around the Longmenshan fault, and the derived decay time constant is 12 days. The evolution of the post-seismic vertical deformation is obtained from precise leveling data measured near the surface rupture. The results demonstrate that the hanging wall is uplifting and the foot wall is subsiding. The amplitude of the post-seismic deformation is lower than that of the co-seismic deformation. The region with the largest post-seismic displacement is located on the leveling route between Maoxian and Beichuan on the hanging wall.

  20. Integrating carbon nanotubes into silicon by means of vertical carbon nanotube field-effect transistors

    KAUST Repository

    Li, Jingqi


    Single-walled carbon nanotubes have been integrated into silicon for use in vertical carbon nanotube field-effect transistors (CNTFETs). A unique feature of these devices is that a silicon substrate and a metal contact are used as the source and drain for the vertical transistors, respectively. These CNTFETs show very different characteristics from those fabricated with two metal contacts. Surprisingly, the transfer characteristics of the vertical CNTFETs can be either ambipolar or unipolar (p-type or n-type) depending on the sign of the drain voltage. Furthermore, the p-type/n-type character of the devices is defined by the doping type of the silicon substrate used in the fabrication process. A semiclassical model is used to simulate the performance of these CNTFETs by taking the conductance change of the Si contact under the gate voltage into consideration. The calculation results are consistent with the experimental observations. This journal is © the Partner Organisations 2014.

  1. Integrating carbon nanotubes into silicon by means of vertical carbon nanotube field-effect transistors. (United States)

    Li, Jingqi; Wang, Qingxiao; Yue, Weisheng; Guo, Zaibing; Li, Liang; Zhao, Chao; Wang, Xianbin; Abutaha, Anas I; Alshareef, H N; Zhang, Yafei; Zhang, X X


    Single-walled carbon nanotubes have been integrated into silicon for use in vertical carbon nanotube field-effect transistors (CNTFETs). A unique feature of these devices is that a silicon substrate and a metal contact are used as the source and drain for the vertical transistors, respectively. These CNTFETs show very different characteristics from those fabricated with two metal contacts. Surprisingly, the transfer characteristics of the vertical CNTFETs can be either ambipolar or unipolar (p-type or n-type) depending on the sign of the drain voltage. Furthermore, the p-type/n-type character of the devices is defined by the doping type of the silicon substrate used in the fabrication process. A semiclassical model is used to simulate the performance of these CNTFETs by taking the conductance change of the Si contact under the gate voltage into consideration. The calculation results are consistent with the experimental observations.

  2. Wall Insulation; BTS Technology Fact Sheet

    Energy Technology Data Exchange (ETDEWEB)

    Southface Energy Institute; Tromly, K.


    Properly sealed, moisture-protected, and insulated walls help increase comfort, reduce noise, and save on energy costs. This fact sheet addresses these topics plus advanced framing techniques, insulation types, wall sheathings, and steps for effective wall construction and insulation.

  3. Lateral and vertical thermal diffusivities in a dense fluidized bed with tubes bundle

    Energy Technology Data Exchange (ETDEWEB)

    Collantes, M.A.; Martin, G.; Le Gal, J.H. [Institut Francais du Petrole (IFP), 92 - Rueil-Malmaison (France)


    Dense fluidized beds are acknowledge as homogeneous systems from both temperature and composition aspects. However, some situation such as very large units or fluidized beds with tubes bundle lead to thermal gradients within the bed. These thermal gradients are due to solids motion limitation and may have detrimental effects on the process. This paper relates investigations aiming an determining lateral and vertical thermal diffusivities in a dense fluidized bed with an without a tubes bundle. These investigations have been carried out with an experimental setup of significant size (bed size = 0.6 x 1.1 x 1.3) and with small particles (less 500 microns) so as to fill some gaps of the literature. Thermal diffusivities have been deduced from temperature gradients measured between a hot wall and a cold wall in a perpendicular fluidized bed and by applying a conventional 2-D conduction model. Lateral thermal conductivities as well as vertical thermal conductivities increase with the gas velocity and the height of the bed, and when the particle size decreases. Immersing a vertical tube bundle into the fluidized bed leads to a significant reduction of the lateral thermal diffusivity, while there is no effect on the vertical thermal diffusivity. Correlations have been drawn from the experimental results. They would have to be applied for calculation of any system running at gas velocity ranging from 0.05 to 0.3 m/s and with particle size between 50 and 300 microns. (authors). 14 refs., 14 figs., 2 tabs.

  4. Numerical Study of the Thermally Conductive Finite Thickness Walls Impact on Heat Transfer Regime in a Closed System in Conditions of Radiant Energy Supply

    Directory of Open Access Journals (Sweden)

    Nee A. E.


    Full Text Available Plane problem of thermogravitational convection in a closed rectangular cavity is numerically solved in conditions of radiant energy supply to the one of the boundaries. Differential heat transfer parameters (fields of temperatures and stream functions for the conjugate (only vertical walls, only horizontal, vertical and horizontal walls and the nonconjugate formulation are obtained. Temperature distributions in the Y direction in the cross section along the axis of symmetry showed that the presence of heat-conducting finite thickness walls leads to a redistribution of the energy which is accumulated by gas and enclosure structures.

  5. Poland Syndrome: Use of Vertical Expandable Prosthetic Titanium Rib System before Walking Age—A Case Report (United States)

    Drebov, Rosen S.; Katsarov, Atanas


    Aim  To present a new therapy for Poland syndrome (PS) using a novel surgical approach: the vertical expandable prosthetic titanium rib (VEPTR) system. Methods  The VEPTR system rib-to-rib variant was used to enhance the chest wall and vertebral column support in a young patient before walking age. Case Report  We present a 12-month-old infant diagnosed with left-sided PS at the age of 6 months associated with missing ribs, scoliosis, and absence of the left pectoral muscles. Because of four missing ribs, paradoxical breathing was present. In addition, the left scapula was protruding into the chest due to the missing rib support. Scoliosis was caused by a left-sided nonsegmented bar of the thoracic spine. Results  We decided to use the VEPTR system before the patient reached walking age to prevent progression of column deformation and future pulmonary problems. To improve the spinal deformity, to stabilize the thorax, and to improve thoracic function, we performed the operation at 1 year of age. At 10-month follow-up, the patient was reevaluated. The construction was still stable and scoliosis had not deteriorated. Conclusion  The VEPTR system is a choice of treatment in young patients with PS to prevent late complications after a child reaches walking age. PMID:28824998

  6. Poland Syndrome: Use of Vertical Expandable Prosthetic Titanium Rib System before Walking Age-A Case Report. (United States)

    Drebov, Rosen S; Katsarov, Atanas


    Aim  To present a new therapy for Poland syndrome (PS) using a novel surgical approach: the vertical expandable prosthetic titanium rib (VEPTR) system. Methods  The VEPTR system rib-to-rib variant was used to enhance the chest wall and vertebral column support in a young patient before walking age. Case Report  We present a 12-month-old infant diagnosed with left-sided PS at the age of 6 months associated with missing ribs, scoliosis, and absence of the left pectoral muscles. Because of four missing ribs, paradoxical breathing was present. In addition, the left scapula was protruding into the chest due to the missing rib support. Scoliosis was caused by a left-sided nonsegmented bar of the thoracic spine. Results  We decided to use the VEPTR system before the patient reached walking age to prevent progression of column deformation and future pulmonary problems. To improve the spinal deformity, to stabilize the thorax, and to improve thoracic function, we performed the operation at 1 year of age. At 10-month follow-up, the patient was reevaluated. The construction was still stable and scoliosis had not deteriorated. Conclusion  The VEPTR system is a choice of treatment in young patients with PS to prevent late complications after a child reaches walking age.

  7. Effects of wall shear stress on unsteady MHD conjugate flow in a porous medium with ramped wall temperature. (United States)

    Khan, Arshad; Khan, Ilyas; Ali, Farhad; Ulhaq, Sami; Shafie, Sharidan


    This study investigates the effects of an arbitrary wall shear stress on unsteady magnetohydrodynamic (MHD) flow of a Newtonian fluid with conjugate effects of heat and mass transfer. The fluid is considered in a porous medium over a vertical plate with ramped temperature. The influence of thermal radiation in the energy equations is also considered. The coupled partial differential equations governing the flow are solved by using the Laplace transform technique. Exact solutions for velocity and temperature in case of both ramped and constant wall temperature as well as for concentration are obtained. It is found that velocity solutions are more general and can produce a huge number of exact solutions correlative to various fluid motions. Graphical results are provided for various embedded flow parameters and discussed in details.

  8. Super Wall Graphics for Learning. (United States)

    Taylor, Anne; Vlastos, George


    Steps for organizing and implementing a program that involves elementary students in beautifying their school with large-scale wall graphics are outlined. Sources of design, drawing hints, painting methods, application techniques, and follow-up activities are discussed. (RM)

  9. Restrained shrinkage of masonry walls

    NARCIS (Netherlands)

    Zijl, G.P.A.G. van; Rots, J.G.


    State of the art computational rnechanics, in combination with experimental programmes have a lot to offer in providing insight, characterization of total behaviour and predictive ability of structural masonry. Here numerical research towards rationalizing masonry wall movement joint positioning and

  10. A highly integrated vertical SU8 valve for stepwise in-series reactions (United States)

    Calvo, V.; Ezkerra, A.; Elizalde, J.; Fernández, L. J.; Berganzo, J.; Mayora, K.; Ruano-López, J. M.


    Stepwise performance of reactions demands highly integrated microfluidic control. The vertical valve presented in this work allows performing reactions in cascade with reduced control requirements, by controlling the rupture of an SU8 wall that separates a chamber from an adjacent evacuation channel. Owing to its vertical construction, the valve can be readily integrated into any geometry with a low increase in footprint. Two valve approaches are presented, which differ in the location of the rupture region, the breaking pressures and the size of the fluidic path open. Breaking the wall about its upper end has proven to be more limited in terms of geometry and resulting gap size, whereas breaking the wall about its root opens a wider fluidic path that allows smooth filling of downstream chambers. Following these conclusions, a sequence of two reactions has been demonstrated, using a wall-valve-regulated double-chamber device. The chosen protocol, DNA concentration, elution and transport, has been successfully accomplished, as evidenced by positive on-chip polymerase chain reaction in a second double-chamber device.

  11. Acute traumatic abdominal wall hernia


    Hartog, Dennis; Tuinebreijer, Wim; Oprel, Pim; Patka, Peter


    textabstractAlthough blunt abdominal trauma is frequent, traumatic abdominal wall hernias (TAWH) are rare. We describe a large TAWH with associated intra-abdominal lesions that were caused by high-energy trauma. The diagnosis was missed by clinical examination but was subsequently revealed by a computed tomography (CT) scan. Repair consisted of an open anatomical reconstruction of the abdominal wall layers with reinforcement by an intraperitoneal composite mesh. The patient recovered well and...

  12. Cell Wall Composition and Candidate Biosynthesis Gene Expression During Rice Development

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Fan; Manisseri, Chithra; Fagerström, Alexandra; Peck, Matthew L.; Vega-Sánchez, Miguel E.; Williams, Brian; Chiniquy, Dawn M.; Saha, Prasenjit; Pattathil, Sivakumar; Conlin, Brian; Zhu, Lan; Hahn, Michael G.; Willats, William G. T.; Scheller, Henrik V.; Ronald, Pamela C.; Bartley, Laura E.


    Cell walls of grasses, including cereal crops and biofuel grasses, comprise the majority of plant biomass and intimately influence plant growth, development and physiology. However, the functions of many cell wall synthesis genes, and the relationships among and the functions of cell wall components remain obscure. To better understand the patterns of cell wall accumulation and identify genes that act in grass cell wall biosynthesis, we characterized 30 samples from aerial organs of rice (Oryza sativa cv. Kitaake) at 10 developmental time points, 3-100 d post-germination. Within these samples, we measured 15 cell wall chemical components, enzymatic digestibility and 18 cell wall polysaccharide epitopes/ligands. We also used quantitative reverse transcription-PCR to measure expression of 50 glycosyltransferases, 15 acyltransferases and eight phenylpropanoid genes, many of which had previously been identified as being highly expressed in rice. Most cell wall components vary significantly during development, and correlations among them support current understanding of cell walls. We identified 92 significant correlations between cell wall components and gene expression and establish nine strong hypotheses for genes that synthesize xylans, mixed linkage glucan and pectin components. This work provides an extensive analysis of cell wall composition throughout rice development, identifies genes likely to synthesize grass cell walls, and provides a framework for development of genetically improved grasses for use in lignocellulosic biofuel production and agriculture.

  13. Design of h-Darrieus vertical axis wind turbine (United States)

    Parra, Teresa; Vega, Carmen; Gallegos, A.; Uzarraga, N. C.; Castro, F.


    Numerical simulation is used to predict the performance of a Vertical Axis Wind Turbine (VAWT) H-Darrieus. The rotor consists of three straight blades with shape of aerofoil of the NACA family attached to a rotating vertical shaft. The influence of the solidity is tested to get design tendencies. The mesh has two fluid volumes: one sliding mesh for the rotor where the rotation velocity is established while the other is the environment of the rotor. Bearing in mind the overall flow is characterized by important secondary flows, the turbulence model selected was realizable k-epsilon with non-equilibrium wall functions. Conservation equations were solved with a Third-Order Muscl scheme using SIMPLE to couple pressure and velocity. During VAWT operation, the performance depends mainly on the relative motion of the rotating blade and has a fundamental period which depends both on the rate of rotation and the number of blades. The transient study is necessary to characterise the hysteresis phenomenon. Hence, more than six revolutions get the periodic behaviour. Instantaneous flows provide insight about wake structure interaction. Time averaged parameters let obtain the characteristic curves of power coefficient.

  14. Design of h-Darrieus vertical axis wind turbine

    Directory of Open Access Journals (Sweden)

    Parra Teresa


    Full Text Available Numerical simulation is used to predict the performance of a Vertical Axis Wind Turbine (VAWT H-Darrieus. The rotor consists of three straight blades with shape of aerofoil of the NACA family attached to a rotating vertical shaft. The influence of the solidity is tested to get design tendencies. The mesh has two fluid volumes: one sliding mesh for the rotor where the rotation velocity is established while the other is the environment of the rotor. Bearing in mind the overall flow is characterized by important secondary flows, the turbulence model selected was realizable k-epsilon with non-equilibrium wall functions. Conservation equations were solved with a Third-Order Muscl scheme using SIMPLE to couple pressure and velocity. During VAWT operation, the performance depends mainly on the relative motion of the rotating blade and has a fundamental period which depends both on the rate of rotation and the number of blades. The transient study is necessary to characterise the hysteresis phenomenon. Hence, more than six revolutions get the periodic behaviour. Instantaneous flows provide insight about wake structure interaction. Time averaged parameters let obtain the characteristic curves of power coefficient.

  15. FFTF vertical sodium storage tank preliminary thermal analysis

    Energy Technology Data Exchange (ETDEWEB)

    Irwin, J.J.


    In the FFTF Shutdown Program, sodium from the primary and secondary heat transport loops, Interim Decay Storage (IDS), and Fuel Storage Facility (FSF) will be transferred to four large storage tanks for temporary storage. Three of the storage tanks will be cylindrical vertical tanks having a diameter of 28 feet, height of 22 feet and fabricated from carbon steel. The fourth tank is a horizontal cylindrical tank but is not the subject of this report. The storage tanks will be located near the FFTF in the 400 Area and rest on a steel-lined concrete slab in an enclosed building. The purpose of this work is to document the thermal analyses that were performed to ensure that the vertical FFTF sodium storage tank design is feasible from a thermal standpoint. The key criterion for this analysis is the time to heat up the storage tank containing frozen sodium at ambient temperature to 400 F. Normal operating conditions include an ambient temperature range of 32 F to 120 F. A key parameter in the evaluation of the sodium storage tank is the type of insulation. The baseline case assumed six inches of calcium silicate insulation. An alternate case assumed refractory fiber (Cerablanket) insulation also with a thickness of six inches. Both cases assumed a total electrical trace heat load of 60 kW, with 24 kW evenly distributed on the bottom head and 36 kW evenly distributed on the tank side wall.

  16. Developing Buoyancy Driven Flow of a Nanofluid in a Vertical Channel Subject to Heat Flux

    Directory of Open Access Journals (Sweden)

    Nirmal C. Sacheti


    Full Text Available The developing natural convective flow of a nanofluid in an infinite vertical channel with impermeable bounding walls has been investigated. It is assumed that the nanofluid is dominated by two specific slip mechanisms and that the channel walls are subject to constant heat flux and isothermal temperature, respectively. The governing nonlinear partial differential equations coupling different transport processes have been solved numerically. The variations of velocity, temperature, and nanoparticles concentration have been discussed in relation to a number of physical parameters. It is seen that the approach to the steady-state profiles of velocity and temperature in the present work is different from the ones reported in a previous study corresponding to isothermal wall conditions.

  17. ATLAS LTCS Vertically Challenged System Lessons Learned (United States)

    Patel, Deepak; Garrison, Matt; Ku, Jentung


    Re-planning of LTCS TVAC testing and supporting RTA (Receiver Telescope Assembly) Test Plan and Procedure document preparation. The Laser Thermal Control System (LTCS) is designed to maintain the lasers onboard Advanced Topographic Laser Altimeter System (ATLAS) at their operational temperatures. In order to verify the functionality of the LTCS, a thermal balance test of the thermal hardware was performed. During the first cold start of the LTCS, the Loop Heat Pipe (LHP) was unable to control the laser mass simulators temperature. The control heaters were fully on and the loop temperature remained well below the desired setpoint. Thermal analysis of the loop did not show these results. This unpredicted behavior of the LTCS was brought up to a panel of LHP experts. Based on the testing and a review of all the data, there were multiple diagnostic performed in order to narrow down the cause. The prevailing theory is that gravity is causing oscillating flow within the loop, which artificially increased the control power needs. This resulted in a replan of the LTCS test flow and the addition of a GSE heater to allow vertical operation.

  18. Lidar measured vertical atmospheric scattering profiles

    NARCIS (Netherlands)

    Kunz, G.J.


    The vertical structure of the atmosphere, which is of invaluable interest to meteorologists, geo-physicists and environmental researchers, can be measured with LIDAR. A method has been proposed and applied to invert lidar signals from vertical soundings to height resolved scattering coefficients. In

  19. Vertical integration from the large Hilbert space (United States)

    Erler, Theodore; Konopka, Sebastian


    We develop an alternative description of the procedure of vertical integration based on the observation that amplitudes can be written in BRST exact form in the large Hilbert space. We relate this approach to the description of vertical integration given by Sen and Witten.

  20. Plasmon Modes of Vertically Aligned Superlattices

    DEFF Research Database (Denmark)

    Filonenko, Konstantin; Duggen, Lars; Willatzen, Morten


    By using the Finite Element Method we visualize the modes of vertically aligned superlattice composed of gold and dielectric nanocylinders and investigate the emitter-plasmon interaction in approximation of weak coupling. We find that truncated vertically aligned superlattice can function as plas...

  1. A vertically resolved model for phytoplankton aggregation

    Indian Academy of Sciences (India)

    components undergo vertical mixing, and phytoplank- ton sink. Phytoplankton growth is limited by the product of nutrient and light terms. The equations for nitrate (NO3) and ... resolved model there is an extra complication: the largest particles that sink out of ...... and biogeochemistry with satellite ocean colour data. Vertically ...

  2. Plasmon Modes of Vertically Aligned Superlattices

    DEFF Research Database (Denmark)

    Filonenko, Konstantin; Duggen, Lars; Willatzen, Morten

    By using the Finite Element Method we visualize the modes of vertically aligned superlattice composed of gold and dielectric nanocylinders and investigate the emitter-plasmon interaction in approximation of weak coupling. We find that truncated vertically aligned superlattice can function as plas...


    African Journals Online (AJOL)

    Vertical plate metering device is intended to minimize seed damage during planting while improving metering efficiency and field capacity. A vertical plate maize seed planter which is adapted for gardens and small holder farmers cultivating less than two hectares has been designed, constructed and tested. The major ...

  4. The green building envelope : Vertical greening

    NARCIS (Netherlands)

    Ottelé, M.


    Planting on roofs and façades is one of the most innovative and fastest developing fields of green technologies with respect to the built environment and horticulture. This thesis is focused on vertical greening of structures and to the multi-scale benefits of vegetation. Vertical green can improve

  5. Vertical Integration, Monopoly, and the First Amendment. (United States)

    Brennan, Timothy J.

    This paper addresses the relationship between the First Amendment, monopoly of transmission media, and vertical integration of transmission and content provision. A survey of some of the incentives a profit-maximizing transmission monopolist may have with respect to content is followed by a discussion of how vertical integration affects those…

  6. Stabilization of the vertical instability by non-axisymmetric coils (United States)

    Turnbull, A. D.; Reiman, A. H.; Lao, L. L.; Cooper, W. A.; Ferraro, N. M.; Buttery, R. J.


    In a published Physical Review Letter (Reiman 2007 Phys. Rev. Lett. 99 135007), it was shown that axisymmetric (or vertical) stability can be improved by placing a set of parallelogram coils above and below the plasma oriented at an angle to the constant toroidal planes. The physics of this stabilization can be understood as providing an effective additional positive stability index. The original work was based on a simplified model of a straight tokamak and is not straightforwardly applicable to a finite aspect ratio, strongly shaped plasma such as in DIII-D. Numerical calculations were performed in a real DIII-D -like configuration to provide a proof of principal that 3-D fields can, in fact raise the elongation limits as predicted. A four field period trapezioid-shaped coil set was developed in toroidal geometry and 3D equilibria were computed using trapezium coil currents of 10 kA , 100 kA , and 500 kA . The ideal magnetohydrodynamics growth rates were computed as a function of the conformal wall position for the n = 0 symmetry-preserving family. The results show an insignificant relative improvement in the stabilizing wall location for the two lower coil current cases, of the order of 10-3 and less. In contrast, the marginal wall position is increased by 7% as the coil current is increased to 500 kA , confirming the main prediction from the original study in a real geometry case. In DIII-D the shift in marginal wall position of 7% would correspond to being able to move the existing wall outward by 5 to 10 cm. While the predicted effect on the axisymmetric stability is real, it appears to require higher coil currents than could be provided in an upgrade to existing facilities. Additional optimization over the pitch of the coils, the number of field periods and the coil positions, as well as plasma parameters, such as the internal inductivity {{\\ell}\\text{i}} , β , and {{q}95} would mitigate this but seem unlikely to change the conclusion.

  7. Size, Shape, and Arrangement of Cellulose Microfibril in Higher Plant Cell Walls

    Energy Technology Data Exchange (ETDEWEB)

    Ding, S. Y.


    Plant cell walls from maize (Zea mays L.) are imaged using atomic force microscopy (AFM) at the sub-nanometer resolution. We found that the size and shape of fundamental cellulose elementary fibril (CEF) is essentially identical in different cell wall types, i.e., primary wall (PW), parenchyma secondary wall (pSW), and sclerenchyma secondary wall (sSW), which is consistent with previously proposed 36-chain model (Ding et al., 2006, J. Agric. Food Chem.). The arrangement of individual CEFs in these wall types exhibits two orientations. In PW, CEFs are horizontally associated through their hydrophilic faces, and the planar faces are exposed, forming ribbon-like macrofibrils. In pSW and sSW, CEFs are vertically oriented, forming layers, in which hemicelluloses are interacted with the hydrophobic faces of the CEF and serve as spacers between CEFs. Lignification occurs between CEF-hemicelluloses layers in secondary walls. Furthermore, we demonstrated quantitative analysis of plant cell wall accessibility to and digestibility by different cellulase systems at real-time using chemical imaging (e.g., stimulated Raman scattering) and fluorescence microscopy of labeled cellulases (Ding et al., 2012, Science, in press).

  8. Direct observation of current-induced motion of a 3D vortex domain wall in cylindrical nanowires

    KAUST Repository

    Ivanov, Yurii P.


    The current-induced dynamics of 3D magnetic vortex domain walls in cylindrical Co/Ni nanowires are revealed experimentally using Lorentz microscopy and theoretically using micromagnetic simulations. We demonstrate that a spin-polarized electric current can control the reversible motion of 3D vortex domain walls, which travel with a velocity of a few hundred meters per second. This finding is a key step in establishing fast, high-density memory devices based on vertical arrays of cylindrical magnetic nanowires.

  9. Cotton fiber: a powerful single-cell model for cell wall and celluloseresearch

    Directory of Open Access Journals (Sweden)

    Candace Hope Haigler


    Full Text Available Cotton fibers are single-celled extensions of the seed epidermis. They can be isolated in pureform as they undergo staged differentiation including primary cell wall synthesis duringelongation and nearly pure cellulose synthesis during secondary wall thickening. Thiscombination of features supports clear interpretation of data about cell walls and cellulosesynthesis in the context of high throughput modern experimental technologies. Priorcontributions of cotton fiber to building fundamental knowledge about cell walls will besummarized and the dynamic changes in cell wall polymers throughout cotton fiberdifferentiation will be described. Recent successes in using stable cotton transformation to altercotton fiber cell wall properties as well as cotton fiber quality will be discussed. Future prospectsto perform experiments more rapidly through altering cotton fiber wall properties via virusinduced gene silencing will be evaluated.

  10. Vertically Integrated Rheology of Deforming Oceanic Lithosphere (United States)

    Mishra, J. K.; Gordon, R. G.


    vertically integrated rheology of oceanic lithosphere determined from laboratory experiments and that the best-fitting power-law exponent for the vertically integrated rheology is insensitive to strain rate. We also find that, except for very young lithosphere (law exponent is insensitive to the age of the lithosphere, with the value of the exponent being between 14 and 16 when failing for thrust faulting for the flow laws of Kohlstedt et al [1995] and between 15 and 19 for more recently published flow laws. These results support the application of thin viscous sheet models to diffuse oceanic plate boundaries, such as the ones accommodating motion between the India, Capricorn, and Australia plates in the Indian Ocean.

  11. Foot use during vertical climbing in chimpanzees (Pan troglodytes). (United States)

    Wunderlich, R E; Ischinger, S B


    Upright bipedalism is a hallmark of hominin locomotion, however debates continue regarding the extent of arboreal locomotion and the nature of bipedalism practiced by early hominins. Pedal form and function play a prominent role in these debates, as the foot is the element that directly interacts with the locomotor substrate. Recent finds have substantially increased the availability of associated foot remains of early hominins and emphasized the enigmatic nature of the early evolution of human bipedalism. New discoveries of associated forefoot remains have afforded the opportunity to assess relative proportions across the forefoot of fossil hominins and illuminated the need for data on relative loading across the forefoot in extant hominoids. In order to provide functional data with which to examine the relationship between bony features and load distribution across the forefoot during climbing, we present the first analysis of plantar pressure distribution across the forefoot of chimpanzees climbing a vertical support. Chimpanzees load the medial metatarsals and first toe disproportionately during vertical climbing. Peak pressures on these elements occur at the end of stance phase during climbing and are higher than on any other elements of the foot. Toe pressures are considerably higher during vertical climbing than during knuckle-walking or movement on horizontal poles, supporting the notion that the plantarly-broad and dorsally-narrow metatarsal heads in chimpanzees and some early hominins are associated with close-packing of the metatarsophalangeal joint during climbing. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Intervention in Vertical Intergroup Relations. (United States)

    Brown, L. Dave

    This paper describes four cases of intervention in the relations between groups of widely differing social status and power. "Dialogs" between high corporate executives and social activities from urban poverty areas in three cities were supported by a foundation interested in promoting long term cooperation between the groups on social projects of…

  13. The Uncanny wall

    DEFF Research Database (Denmark)

    Tinwell, Angela; Grimshaw, Mark Nicholas; Williams, Andrew


    This paper proposes that increasing technological sophistication in the creation of realism for human-like, virtual characters is matched by increasing technological discernment on the part of the viewer. One of the goals for achieving a realism that is believable for virtual characters...... is to overcome the Uncanny Valley where perceived strangeness or familiarity is rated against perceived human-likeness. Empirical evidence shows that the Uncanny can be applied to virtual characters, yet implies a more complex picture than the shape of a deep valley with a sharp gradient as depicted in Mori......'s original plot of the Uncanny Valley. Our results imply that: (1) perceived familiarity is dependent upon a wider range of variables other than appearance and behaviour and (2) for realistic, human-like characters, the Uncanny Valley is an impossible traverse, is not supported fully by empirical evidence...

  14. Effect of SMA bars on cyclic behaviour of low-rise shear walls (United States)

    Liao, W. I.; Effendy, E.; Song, G.; Mo, Y. L.; Hsu, T. T. C.; Loh, C. H.


    Past RC panel tests performed at the University of Houston show that reinforced concrete membrane elements under reversed cyclic loading have much greater ductility when steel bars are provided in the direction of principal tensile stress. In order to improve the ductility of low-rise shear walls under earthquake loading, high seismic performance shear walls have been proposed to have steel bars in the same direction as the tensile principal direction of applied stresses in the critical region of shear walls. This paper presents the results of reversed cyclic tests on three low-rise shear walls with SMA bars. The height, width, and thickness of the designed shear walls are 1.0 m, 2.0 m, and 0.12 m, respectively. SMA bars are provided in the directions of 27 degrees to the horizontal that are in the diagonal direction. The reinforcing bars of the shear walls are in vertical and horizontal directions. The ratios of both SMA and reinforcing bars are 0.24%. The main parameter used in the study is the type of SMA bar, namely Superelastic and Martensite SMA bars. The test results from the walls with SMA bars are also compared to a conventional wall without SMA bars. Test results also show that the maximum shear strengths of the tested walls are affected by the SMA bars. It was found that the shear wall with Martensite SMA bars has greater residual displacement. In contrast, the shear wall with superelastic SMA bars has less residual displacement. At the ultimate state, one of the four superelastic SMA bars buckled, resulting in less energy dissipation capacity than the expected value. Preventing buckling of SMA bars is the research focus in the near future.


    Directory of Open Access Journals (Sweden)

    Y. He


    Full Text Available Automated 3D building model generation continues to attract research interests in photogrammetry and computer vision. Airborne Light Detection and Ranging (LIDAR data with increasing point density and accuracy has been recognized as a valuable source for automated 3D building reconstruction. While considerable achievements have been made in roof extraction, limited research has been carried out in modelling and reconstruction of walls, which constitute important components of a full building model. Low point density and irregular point distribution of LIDAR observations on vertical walls render this task complex. This paper develops a novel approach for wall reconstruction from airborne LIDAR data. The developed method commences with point cloud segmentation using a region growing approach. Seed points for planar segments are selected through principle component analysis, and points in the neighbourhood are collected and examined to form planar segments. Afterwards, segment-based classification is performed to identify roofs, walls and planar ground surfaces. For walls with sparse LIDAR observations, a search is conducted in the neighbourhood of each individual roof segment to collect wall points, and the walls are then reconstructed using geometrical and topological constraints. Finally, walls which were not illuminated by the LIDAR sensor are determined via both reconstructed roof data and neighbouring walls. This leads to the generation of topologically consistent and geometrically accurate and complete 3D building models. Experiments have been conducted in two test sites in the Netherlands and Australia to evaluate the performance of the proposed method. Results show that planar segments can be reliably extracted in the two reported test sites, which have different point density, and the building walls can be correctly reconstructed if the walls are illuminated by the LIDAR sensor.

  16. Identification of Cell Wall Synthesis Regulatory Genes Controlling Biomass Characteristics and Yield in Rice (Oryza Sativa)

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Zhaohua PEng [Mississippi State University; Ronald, Palmela [UC-Davis; Wang, Guo-Liang [The Ohio State University


    synthesis pathway genes are induced by removal of cell wall, some cell wall synthesis apparatus must be shared in both cases. The cell wall re-synthesis mechanism may have broad application because our preliminary assay indicates that the cell wall characteristics are highly different from those produced during cytokinesis. A thorough understanding on the regulation of cell wall re-synthesis may lead to improvement of cell wall characteristics. b) Removal of cell wall results in chromatin decondensation Another interesting observation was that removal of cell wall was associated with substantial chromatin change. Our DNA DAPI stain, chromatin MNase digestion, histone modification proteomics, protein differential expression analysis, and DNA oligo array studies all supported that substantial chromatin change was associated with removal of cell wall treatment. It is still under investigation if the chromatin change is associated with activation of cell wall synthesis genes, in which chromatin remodeling is required. Another possibility is that the cell wall is required for stabilizing the chromatin structure in plant cells. Given that spindle fiber is directly connected with both chromatin structure and cell wall synthesis, it is possible that there is an intrinsic connection between cell wall and chromatin.

  17. Active particle control experiments and critical particle flux discriminating between the wall pumping and fuelling in the compact plasma wall interaction device CPD spherical tokamak (United States)

    Zushi, H.; Hirooka, Y.; Bhattacharyay, R.; Sakamoto, M.; Nakashima, Y.; Yoshinaga, T.; Higashizono, Y.; Hanada, K.; Nishino, N.; Yoshida, N.; Tokunaga, K.; Kado, S.; Shikama, T.; Kawasaki, S.; Okamoto, K.; Miyazaki, T.; Honma, H.; Sato, K. N.; Nakamura, K.; Idei, H.; Hasegawa, M.; Nakashima, H.; Higashijima, A.


    Two approaches associated with wall recycling have been performed in a small spherical tokamak device CPD (compact plasma wall interaction experimental device), that is, (1) demonstration of active particle recycling control, namely, 'active wall pumping' using a rotating poloidal limiter whose surface is continuously gettered by lithium and (2) a basic study of the key parameters which discriminates between 'wall pumping and fuelling'. For the former, active control of 'wall pumping' has been demonstrated during 50 kW RF current drive discharges whose pulse length is typically ~300 ms. Although the rotating limiter is located at the outer board, as soon as the rotating drum is gettered with lithium, hydrogen recycling measured with Hα spectroscopy decreases by about a factor of 3 not only near the limiter but also in the centre stack region. Also, the oxygen impurity level measured with O II spectroscopy is reduced by about a factor of 3. As a consequence of the reduced recycling and impurity level, RF driven current has nearly doubled at the same vertical magnetic field. For the latter, global plasma wall interaction with plasma facing components in the vessel is studied in a simple torus produced by electron cyclotron waves with Ip static gas balance (pressure measurement) without external pumping systems has been performed to investigate the role of particle flux on a transition of 'wall fuelling' to 'wall pumping'. It is found that a critical particle flux exists to discriminate between them. Beyond the critical value, a large fraction (~80%) of pressure drop ('wall pumping') is found, suggesting that almost all injected particles are retained in the wall. Below it, a significant pressure rise ('wall fuelling') is found, which indicates that particles are fuelled from the wall during/just after the discharge. Shot history effects (integrated particle recycling behaviour from the plasma facing surfaces) are seen on that the critical particle flux is reducing

  18. Soliton-like magnetic domain wall motion induced by the interfacial Dzyaloshinskii-Moriya interaction (United States)

    Ono, Teruo

    Topological defects such as magnetic solitons, vortices, Bloch lines, and skyrmions start to play an important role in modern magnetism due to their extraordinary stability which can be hailed as future memory devices. Recently, novel type of antisymmetric exchange interaction, namely the Dzyaloshinskii-Moriya interaction (DMI), has been uncovered and found to influence on the formation of topological defects. Exploring how the DMI affects the dynamics of topological defects is therefore an important task. Here we investigate the dynamics of the magnetic domain wall (DW) under a DMI by developing a time-of-flight measurement scheme which allows us to measure the DW velocity for magnetic fields up to 0.3T. For a weak DMI, the trend of DW velocity follows the Walker's model which predicts that the velocity of DW increases with field up to a threshold (Walker field) and decreases abruptly. On the other hand, for a strong DMI, velocity breakdown is completely suppressed and the DW keeps its maximum velocity even far above the Walker field. Such a distinct trend of the DW velocity, which has never been predicted, can be explained in terms of magnetic soliton, of which topology can be protected by the DMI. Importantly, such a soliton-like DW motion is only observed in two dimensional systems, implying that the vertical Bloch lines (VBLs) creating inside of the magnetic domain-wall play a crucial role. This work was partly supported by JSPS KAKENHI Grant Numbers 15H05702, 26870300, 26870304, 26103002, 25.4251, Collaborative Research Program of the Institute for Chemical Research, Kyoto University, and R & D Project for ICT Key Technology of MEXT from the Japan Society for the Promotion of Science (JSPS).

  19. The influence of different screw tightening forces on the vertical misfit of implant-supported frameworks Avaliação do efeito da força de aperto de parafusos de retenção na desadaptação marginal de próteses sobre implantes

    Directory of Open Access Journals (Sweden)

    Diego Klee de Vasconcellos


    Full Text Available OBJECTIVES: The present in vitro study was designed to compare the differences in the vertical misfit of implant-supported frameworks using three different forces for tightening the bridge locking screws: fastening by hand until first resistance, and using torque drivers with 10 and 20Ncm. METHODS: The investigation was conducted based on the results given by 9 six-unit nickel-chromium (2 abutments/ 4 pontics screw-retained implant-supported frameworks. The structures were exposed to simulated porcelain firings. The marginal misfit measurements were made using a traveling measuring microscope at selected screw tightening forces: fastening by hand until first resistance, and using torque drivers with 10 and 20Ncm. The results were submitted to one-way ANOVA with repeated measures on one factor, and post hoc pairwise comparisons using Tukey test (5%. RESULTS: The mean marginal misfit of the frameworks, fastening the screws by hand until first resistance, was 41.56µm (SD±12.45µm. The use of torque driver devices caused a significant reduction in marginal opening (pO presente estudo avaliou o efeito da força de aperto de parafusos de retenção na desadaptação marginal de próteses sobre implantes. A investigação foi conduzida baseada em resultados fornecidos por nove estruturas metálicas implanto-suportadas de seis elementos (02 retentores e 04 pônticos, retidas por parafusos. A mensuração da desadaptação marginal foi realizada com auxílio de microscópio óptico, nos seguintes momentos: M1: aperto com chave manual até a primeira resistência do parafuso; M2: aperto utilizando torquímetro mecânico com 10Ncm e M3: aperto utilizando torquímetro mecânico com 20Ncm. As médias de desadaptação foram submetidas à análise estatística (ANOVA e Tukey. O emprego de torquímetros mecânicos, independente do valor de torque, determinou redução significativa na abertura marginal (p<0,05. A desadaptação média na interface conex

  20. Vacuum template synthesis of multifunctional nanotubes with tailored nanostructured walls (United States)

    Filippin, A. Nicolas; Macias-Montero, Manuel; Saghi, Zineb; Idígoras, Jesús; Burdet, Pierre; Barranco, Angel; Midgley, Paul; Anta, Juan A.; Borras, Ana


    A three-step vacuum procedure for the fabrication of vertical TiO2 and ZnO nanotubes with three dimensional walls is presented. The method combines physical vapor deposition of small-molecules, plasma enhanced chemical vapor deposition of inorganic functional thin films and layers and a post-annealing process in vacuum in order to remove the organic template. As a result, an ample variety of inorganic nanotubes are made with tunable length, hole dimensions and shapes and tailored wall composition, microstructure, porosity and structure. The fabrication of multishell nanotubes combining different semiconducting oxides and metal nanoparticles is as well explored. This method provides a feasible and reproducible route for the fabrication of high density arrays of vertically alligned nanotubes on processable substrates. The emptying mechanism and microstructure of the nanotubes have been elucidated through SEM, STEM, HAADF-STEM tomography and energy dispersive X-ray spectroscopy. In this article, as a proof of concept, it is presented the straightforward integration of ZnO nanotubes as photoanode in a photovoltaic cell and as a photonic oxygen gas sensor.

  1. MHD Electrode and wall constructions (United States)

    Way, Stewart; Lempert, Joseph


    Electrode and wall constructions for the walls of a channel transmitting the hot plasma in a magnetohydrodynamic generator. The electrodes and walls are made of a plurality of similar modules which are spaced from one another along the channel. The electrodes can be metallic or ceramic, and each module includes one or more electrodes which are exposed to the plasma and a metallic cooling bar which is spaced from the plasma and which has passages through which a cooling fluid flows to remove heat transmitted from the electrode to the cooling bar. Each electrode module is spaced from and electrically insulated from each adjacent module while interconnected by the cooling fluid which serially flows among selected modules. A wall module includes an electrically insulating ceramic body exposed to the plasma and affixed, preferably by mechanical clips or by brazing, to a metallic cooling bar spaced from the plasma and having cooling fluid passages. Each wall module is, similar to the electrode modules, electrically insulated from the adjacent modules and serially interconnected to other modules by the cooling fluid.

  2. Functional domain walls in multiferroics. (United States)

    Meier, Dennis


    During the last decade a wide variety of novel and fascinating correlation phenomena has been discovered at domain walls in multiferroic bulk systems, ranging from unusual electronic conductance to inseparably entangled spin and charge degrees of freedom. The domain walls represent quasi-2D functional objects that can be induced, positioned, and erased on demand, bearing considerable technological potential for future nanoelectronics. Most of the challenges that remain to be solved before turning related device paradigms into reality, however, still fall in the field of fundamental condensed matter physics and materials science. In this topical review seminal experimental findings gained on electric and magnetic domain walls in multiferroic bulk materials are addressed. A special focus is put on the physical properties that emerge at so-called charged domain walls and the added functionality that arises from coexisting magnetic order. The research presented in this review highlights that we are just entering a whole new world of intriguing nanoscale physics that is yet to be explored in all its details. The goal is to draw attention to the persistent challenges and identify future key directions for the research on functional domain walls in multiferroics.

  3. The feasibility of removable prefab diaphragm walls

    NARCIS (Netherlands)

    Amaarouk, R.; De Gijt, J.G.; Braam, C.R.


    A diaphragm wall is a cast in-situ reinforced concrete retaining wall applied in, among others, quay walls. The main advantages of this type of retaining wall are that it can be made in almost every preferred length and that it can resist high structural loads. However, there are several

  4. Morphopatological and histochemical highlights in normal and varicose vein wall

    Directory of Open Access Journals (Sweden)

    Alina Condor


    Full Text Available The nutrition of the venous wall appears to be an important factor in the vascularfibrillar trophicity and in the dynamic of the extracellular matrix formation for the normal veins and, for the chronic venous ulcers of legs, on period of healing. Sequential biopsies were taken at various levels of venous wall of external and internal saphena in 16 cases presenting a chronic condition of legs venous system (35-58 years old patients, both sexes. 8 vein fragments with normal macroscopic appearance were also taken, in necropsy. These samples were analyzed using regular morphological methods and some histochemical reactions to reveal the glycogen, glycoproteins, and glycosaminoglycans substrates. There were been used the Gomori silver impregnation and orcein to expose some specific substrates like reticulin or elastin. Other staining methods, like Gomori trichrome, were used to differentiate the specific structures of the vein wall, were used to differentiate the specific structures of the vein wall. A rich vascularization of normal and dilated vein wall could be remarked.Angiogenesis in vein wall and vasa vasorum changes as well as alcianophilic of vascular intima seem to be reactive and protective factors, depending on the applied therapeutic modalities. The veins are weak structures whose integrity depends on the thickness of the media and the support of neighboring structures.

  5. Evolution Sustainable Green Inner-wall with Flexible Floor Plan

    Directory of Open Access Journals (Sweden)

    Tawil N.M.


    Full Text Available The trend of renovate residential houses especially the interior of the house has become a common phenomenon for homeowners nowadays in Malaysia. This scenario is quiet concern because sometimes no modifications to comply with the law and the guidelines set by the government housing. Modifications with not done properly can cause injury and harm to families and the people around. To reduce this problem, the concept of sustainable inner walls with flexible floor plan should be incorporated in every house in Malaysia. This is because the wall is the basic structure of a building and usually serves as the border, supporting structures and dividing the space with another space. Wall also causes an increase of the price of a house. This is due to the increase in raw material costs and labor costs, land subsidence have to bear by the developer. The increasing in house prices is causing among Malaysians, especially young executives cannot afford to buy their first home. To reduce the price of the home, reduction in construction interior wall in wet construction should be done and replaced with the sustainable inner wall. This sustainable inner wall also can save the space and the owner simplify can added or reduced the room according their need without spending too much money for renovation in the future.

  6. Installing a HDPE vertical containment and collection system in one pass utilizing a deep trencher

    Energy Technology Data Exchange (ETDEWEB)

    Bocchino, W.M. [Groundwater Control Inc., Jacksonville, FL (United States); Burson, B. [Groundwater Control, Houston, TX (United States)


    A unique method has been developed to install high density polyethylene (HDPE) vertical containment panels and a horizontal collection system for the containment and collection of contaminated groundwater. Unlike other means of creating this type of system, this barrier wall and collection system is installed in one step and in one narrow trench, utilizing a one-pass deep trencher. Originally HDPE vertical barriers were installed using conventional slurry trenching techniques. Use of this method raised questions of trench stability and disposal costs for the trench spoils. In addition, if a collection system was desired, a separate trench or vertical wells were required. In response to these concerns, a trenchless vibratory installation method was developed. Although this method addressed the concerns of trench stability and disposal costs, it raised a whole new set of concerns dealing with drivable soil conditions, buried debris and obstructions. Again, if a collection system was desired, a separate trench or vertical wells had to be installed. The latest development, the one-pass, deep trencher, has eliminated or significantly reduced the previously discussed construction concerns. The trencher methods reduce the amount of spoils generated because a trench width of 61 cm (24 inches) is constantly maintained by the machine. Additionally, soil classification and density are not as critical as with a vibratory installation. This is due to the trencher`s ability to trench in all but the hardest of materials (blow counts exceeding 35 blows/ft). Finally, the cost to add a collection system adjacent to the cutoff wall is substantially reduced and is limited only to the cost of the additional hydraulic fill and 4 inches HDPE collection piping. The trench itself is already constructed with the installation of the wall.

  7. Unconventional vertical word-order impairs reading. (United States)

    Bonfiglioli, Claudia


    Western written languages unfold across both the horizontal (from left to right) and the vertical (from top to bottom) dimensions. Culturally determined horizontal reading/writing habits are so pervasive that their influence can be found not only in visual scanning but also in performance across different domains and tasks. However, little is known on the effects of vertical word order. In the present study, a lexical decision task is used to show that reading performance is less efficient when verbal material is vertically arranged following a bottom-to-top order.

  8. Surface tension profiles in vertical soap films (United States)

    Adami, N.; Caps, H.


    Surface tension profiles in vertical soap films are experimentally investigated. Measurements are performed by introducing deformable elastic objets in the films. The shape adopted by those objects once set in the film is related to the surface tension value at a given vertical position by numerically solving the adapted elasticity equations. We show that the observed dependency of the surface tension versus the vertical position is predicted by simple modeling that takes into account the mechanical equilibrium of the films coupled to previous thickness measurements.

  9. A Novel Method to Grow Vertically Aligned Silicon Nanowires on Si (111 and Their Optical Absorption

    Directory of Open Access Journals (Sweden)

    Tzuen-Wei Ho


    Full Text Available In this study we grew silicon nanowires (SiNWs on Si (111 substrate by gold-catalyzed vapor liquid solid (VLS process using tetrachlorosilane (SiCl4 in a hot-wall chemical vapor deposition reactor. SiNWs with 150–200 nm diameters were found to grow along the orientations of all 〈111〉 family, including the vertical and the inclined, on Si (111. The effects of various process conditions, including SiCl4 concentration, SiCl4 feeding temperature, H2 annealing, and ramp cooling, on the crystal quality and growth orientation of SiNWs, were studied to optimize the growth conditions. Furthermore, a novel method was developed to reliably grow vertically aligned SiNWs on Si (111 utilizing the principle of liquid phase epitaxy (LPE. A ramp-cooling process was employed to slowly precipitate the epitaxial Si seeds on Si (111 after H2 annealing at 650°C. Then, after heating in SiCl4/H2 up to 850°C to grow SiNWs, almost 100% vertically aligned SiNWs could be achieved reproducibly. The high degree of vertical alignment of SiNWs is effective in reducing surface reflection of solar light with the reflectance decreasing with increasing the SiNWs length. The vertically aligned SiNWs have good potentials for solar cells and nano devices.

  10. Seismic Behaviour of Composite Steel Fibre Reinforced Concrete Shear Walls (United States)

    Boita, Ioana-Emanuela; Dan, Daniel; Stoian, Valeriu


    In this paper is presented an experimental study conducted at the “Politehnica” University of Timisoara, Romania. This study provides results from a comprehensive experimental investigation on the behaviour of composite steel fibre reinforced concrete shear walls (CSFRCW) with partially or totally encased profiles. Two experimental composite steel fibre reinforced concrete walls (CSFRCW) and, as a reference specimen, a typical reinforced concrete shear wall (RCW), (without structural reinforcement), were fabricated and tested under constant vertical load and quasi-static reversed cyclic lateral loads, in displacement control. The tests were performed until failure. The tested specimens were designed as 1:3 scale steel-concrete composite elements, representing a three storeys and one bay element from the base of a lateral resisting system made by shear walls. Configuration/arrangement of steel profiles in cross section were varied within the specimens. The main objective of this research consisted in identifying innovative solutions for composite steel-concrete shear walls with enhanced performance, as steel fibre reinforced concrete which was used in order to replace traditional reinforced concrete. A first conclusion was that replacing traditional reinforcement with steel fibre changes the failure mode of the elements, as from a flexural mode, in case of element RCW, to a shear failure mode for CSFRCW. The maximum lateral force had almost similar values but test results indicated an improvement in cracking response, and a decrease in ductility. The addition of steel fibres in the concrete mixture can lead to an increase of the initial cracking force, and can change the sudden opening of a crack in a more stable process.

  11. Turbine airfoil with outer wall thickness indicators (United States)

    Marra, John J; James, Allister W; Merrill, Gary B


    A turbine airfoil usable in a turbine engine and including a depth indicator for determining outer wall blade thickness. The airfoil may include an outer wall having a plurality of grooves in the outer surface of the outer wall. The grooves may have a depth that represents a desired outer surface and wall thickness of the outer wall. The material forming an outer surface of the outer wall may be removed to be flush with an innermost point in each groove, thereby reducing the wall thickness and increasing efficiency. The plurality of grooves may be positioned in a radially outer region of the airfoil proximate to the tip.

  12. Quantum Dynamics of Spin Wave Propagation through Domain Walls

    NARCIS (Netherlands)

    Yuan, S.; Raedt, H. De; Miyashita, S.

    Through numerical solution of the time-dependent Schrödinger equation, we demonstrate that magnetic chains with uniaxial anisotropy support stable structures, separating ferromagnetic domains of opposite magnetization. These structures, domain walls in a quantum system, are shown to remain stable if

  13. Abdominal wall hernia and pregnancy

    DEFF Research Database (Denmark)

    Jensen, K K; Henriksen, N A; Jorgensen, L N


    PURPOSE: There is no consensus as to the treatment strategy for abdominal wall hernias in fertile women. This study was undertaken to review the current literature on treatment of abdominal wall hernias in fertile women before or during pregnancy. METHODS: A literature search was undertaken in Pub......Med and Embase in combination with a cross-reference search of eligible papers. RESULTS: We included 31 papers of which 23 were case reports. In fertile women undergoing sutured or mesh repair, pain was described in a few patients during the last trimester of a subsequent pregnancy. Emergency surgery...... of incarcerated hernias in pregnant women, as well as combined hernia repair and cesarean section appears as safe procedures. No major complications were reported following hernia repair before or during pregnancy. The combined procedure of elective cesarean section and abdominal wall hernia repair was reported...

  14. Acalculous Diffuse Gallbladder Wall Thickening in Children


    Lee, Ji Haeng; No, Young Eun; Lee, Yeoun Joo; Hwang, Jae Yeon; Lee, Joon Woo; Park, Jae Hong


    Purpose Gallbladder (GB) wall thickening can be found in various conditions unrelated to intrinsic GB disease. We investigated the predisposing etiologies and the outcome of acalculous GB wall thickening in children. Methods We retrospectively analyzed 67 children with acalculous GB wall thickening who had visited our institute from June 2010 to June 2013. GB wall thickening was defined as a GB wall diameter >3.5 mm on abdominal ultrasound examination or computed tomography. Underlying diseas...

  15. Vertical Motions of Oceanic Volcanoes (United States)

    Clague, D. A.; Moore, J. G.


    lasting a few hundred thousand years as the island migrates over a broad flexural arch related to isostatic compensation of a nearby active volcano. The arch is located about 190±30 km away from the center of volcanic activity and is also related to the rejuvenated volcanic stage on the islands. Reefs on Oahu that are uplifted several tens of m above sea level are the primary evidence for uplift as the islands over-ride the flexural arch. At the other end of the movement spectrum, both in terms of magnitude and length of response, are the rapid uplift and subsidence that occurs as magma is accumulated within or erupted from active submarine volcanoes. These changes are measured in days to years and are of cm to m variation; they are measured using leveling surveys, tiltmeters, EDM and GPS above sea level and pressure gauges and tiltmeters below sea level. Other acoustic techniques to measure such vertical movement are under development. Elsewhere, evidence for subsidence of volcanoes is also widespread, ranging from shallow water carbonates on drowned Cretaceous guyots, to mapped shoreline features, to the presence of subaerially-erupted (degassed) lavas on now submerged volcanoes. Evidence for uplift is more limited, but includes makatea islands with uplifted coral reefs surrounding low volcanic islands. These are formed due to flexural uplift associated with isostatic loading of nearby islands or seamounts. In sum, oceanic volcanoes display a long history of subsidence, rapid at first and then slow, sometimes punctuated by brief periods of uplift due to lithospheric loading by subsequently formed nearby volcanoes.

  16. Vertical vergence adaptation produces an objective vertical deviation that changes with head tilt. (United States)

    Irsch, Kristina; Guyton, David L; Ramey, Nicholas A; Adyanthaya, Rohit S; Ying, Howard S


    To document the cyclovertical ocular motor mechanism used for vertical fusion in healthy subjects, and to explore whether vertical vergence training in healthy individuals can produce objectively confirmed vertical deviations that change with head tilt, revealing a basic mechanism that can produce a pattern of misalignment in an otherwise normal ocular motor system that is similar to superior oblique muscle paresis (SOP). Seven subjects with normal orthoptic examinations were adapted to vertical image disparities using our tilting haploscopic eye-tracking apparatus presenting concentric circle targets without torsional cues. Static eye positions were recorded with head straight and when tilted 45 degrees to the left and right, during both binocular and monocular viewing. Vertical fusional vergence was accompanied by a cycloversion, with the downward-moving eye intorting and the upward-moving eye extorting, implicating primary involvement of the oblique extraocular muscles. After adaptation to the slowly increasing vertical target separation, all subjects developed a temporary vertical deviation in the straight ahead position that increased with head tilt to one side and decreased with head tilt to the other side. These results not only show that head-tilt-dependent changes in vertical deviation are not necessarily pathognomonic for SOP, but also, and more importantly, suggest mechanisms that can mimic SOP and suggest a possible role for vertical vergence training in reducing deviations and thus the amount of head tilt required for fusion. Ultimately, vertical vergence training may provide an adjunct or alternative to extraocular muscle surgery in selected cases.

  17. Solar Walls for concrete renovation

    DEFF Research Database (Denmark)

    Gramkow, Lotte; Vejen, Niels Kristian; Olsen, Lars


    This repport gives a short presentation of three full-scale testing solar walls, the construction including the architectural design, materials and components, transportation and storage of solar enegy, the effect on the construction behind, statics and practical experience.The results of the mea......This repport gives a short presentation of three full-scale testing solar walls, the construction including the architectural design, materials and components, transportation and storage of solar enegy, the effect on the construction behind, statics and practical experience.The results...

  18. Wave Forces on Crown Walls

    DEFF Research Database (Denmark)

    Pedersen, Jan; Burcharth, H. F.


    This paper presents some of the results from a large parametric laboratory study including more than 200 long-duration model tests. The study addresses both the wave forces imposed on the breakwater crown wall as well as the performance of the structure in reducing the wave overtopping. The testing...... programme includes variations of the sea state parameters and of the geometrical configuration of the breakwater and crown wall. Basic relations between forces/overtopping and the varied parameters are examined and preliminary design guidelines for structures within the tested range of variations...

  19. HL-LHC vertical cryostat during construction

    CERN Multimedia

    Lanaro, Andrea


    7m high "Cluster D" vertical test cryostat during construction at contractor's premises, Alca Technology Srl, in Schio, Italy. The inner helium vessel with its heat exchanger are visible. To be installed in the D pit in SMA18.

  20. Thermal vertical bimorph actuators and their applications

    CERN Document Server

    Sehr, H J


    In this thesis, a novel concept for lateral actuators based on vertical bimorphs is presented. Vertical bimorphs consist of silicon beams side-coated with aluminium, which bend when heated due to the different thermal expansion coefficients of the two materials causing a displacement in the wafer plane. The heating of the actuator is provided by an electrical current through the silicon beam. The simplest implementation of a vertical bimorph actuator is a clamped-clamped beam. To obtain higher deflections, a meander shaped actuator has been designed. By combining four meander actuators, a two-dimensional positioning stage has been realised. The meander actuator has also been applied for normally closed and normally open micro-relays. Analytical calculations and ANSYS simulations have been carried out to predict the physical behaviour of the bimorph devices, including temperature distribution, static deflection, vertical stiffness, thermal time constant and lateral resonances. For both the clamped-clamped beam...

  1. Multiloop string vertices from the path integral

    Energy Technology Data Exchange (ETDEWEB)

    Bochicchio, M.; Lerda, A.


    We derive the multiloop vertices for the bosonic string using path integral methods and establish a precise equivalence between the functional approach to string perturbation theory and the operator formalism on Riemann surfaces recently developed by various authors.

  2. Vertical Land Change, Perry County, Kentucky (United States)

    U.S. Geological Survey, Department of the Interior — The vertical land change activity focuses on the detection, analysis, and explanation of topographic change. These detection techniques include both quantitative...

  3. Nonlinear Modeling of Autoclaved Aerated Concrete Masonry Wall Strengthened using Ferrocement Sandwich Structure

    KAUST Repository

    M., Abdel-Mooty


    Autoclaved Aerated Concrete (AAC) block are used mainly as non-load-bearing walls that provide heat insulation. This results in considerable saving in cooling energy particularly in hot desert environment with large variation of daily and seasonal temperatures. However, due to the relatively low strength there use load bearing walls is limited to single storey and low-rise construction. A system to enhance the strength of the AAC masonry wall in resisting both inplane vertical and combined vertical and lateral loads using ferrocement technology is proposed in this research. The proposed system significantly enhances the load carrying capacity and stiffness of the AAC wall without affecting its insulation characteristics. Ferrocement is made of cement mortar reinforced with closely spaced wire mesh. Full scale wall specimens with height of 2100mm and width of 1820mm were tested with different configuration of ferrocement. A finite elementmodel is developed and verified against the experimentalwork. The results of the finite element model correlates well with the experimental results.

  4. Risks Facing the Retailers and Vertical Restraints

    Directory of Open Access Journals (Sweden)

    Dzagurova Nataliya, B.


    Full Text Available Vertical restraints such as exclusive territories may be considered as an alternative to the compensation paid to retailers for taking the risks associated with market shocks. For the first time this approach has been put forward in (Rey and Tirole, 1986. In (Hansen and Motta, 2015 this concept has been further developed, but these authors have come a diametrically opposite result to what Rey & Tirole had reported. The goal of both papers was to compare exclusive territories and retailers’ competition from the point of view of the supplier. In (Rey and Tirole, 1986 the competition was the preferred solution, in (Hansen and Motta, 2015 - the exclusive territories. The explanation of this discrepancy proposed in (Hansen and Motta, 2015 doesn't look convincing enough. The paper proposes a new explanation based on the analysis of the attractiveness of the considered lotteries for the retailers. In (Rey and Tirole, 1986 they were ready to pay for the lottery, but in (Hansen and Motta, 2015 - pretend to get a compensation. Accordingly, in the first case the supplier prefers to allow competition between dealers, in the second - to provide exclusive territories in order to reduce the compensation to be paid to the dealer for participating in the lottery. The paper discusses that the better solution is to consider not the risks associated with market shocks, but the retailers’ risks associated with the so called «cooperative specific investments» (manufacturer can prefer another partner on ex post stage. Trying to support the retailers’ incentives to make cooperative investments, supplier voluntarily redistributes control in favor of retailers.

  5. A Computational Framework for Vertical Video Editing


    Gandhi, Vineet; Ronfard, Rémi


    International audience; Vertical video editing is the process of digitally editing the image within the frame as opposed to horizontal video editing, which arranges the shots along a timeline. Vertical editing can be a time-consuming and error-prone process when using manual key-framing and simple interpolation. In this paper, we present a general framework for automatically computing a variety of cinematically plausible shots from a single input video suitable to the special case of live per...

  6. Updated Vertical Extent of Collision Damage

    DEFF Research Database (Denmark)

    Tagg, R.; Bartzis, P.; Papanikolaou, P.


    The probabilistic distribution of the vertical extent of collision damage is an important and somewhat controversial component of the proposed IMO harmonized damage stability regulations for cargo and passenger ships. The only pre-existing vertical distribution, currently used in the international...... cargo ship regulations, was based on a very simplified presumption of bow heights. This paper investigates the development of this damage extent distribution based on three independent methodologies; actual casualty measurements, world fleet bow height statistics, and collision simulation modeling...

  7. Vertical Jump: Biomechanical Analysis and Simulation Study


    Babic, Jan; Lenarcic, Jadran


    By building an efficient biorobotic model which includes an elastic model of the biarticular muscle gastrocnemius and by simulation of the vertical jump we have demonstrated that biarticular links contribute a great deal to the performance of the vertical jump. Besides, we have shown that timing of the biarticular link activation and stiffness of the biarticular link considerably influence the height of the jump. Methodology and results of our study offer an effective tool for the design of t...


    Directory of Open Access Journals (Sweden)

    A. Ursu


    Full Text Available The features of structure of some parent materials essentially influence of direction of pedogenesis, cause the processes of lithomorphism. On heavy tertiary clays in different conditionsare formed the special genetic type (vertisols or transitive to lithomorphic subtype of zonal soil (vertic soil. In article the characteristic of vertisols (the subtype of mollic and ochric and thesubtypes of vertic chernozems and grey soils is given.

  9. Effects of Geofoam Panels on Static Behavior of Cantilever Retaining Wall

    Directory of Open Access Journals (Sweden)

    Navid Hasanpouri Notash


    Full Text Available Geofoam is one of the geosynthetic products that can be used in geotechnical applications. According to researches, expanded polystyrene (EPS geofoam placed directly against a rigid retaining wall has been proposed as a strategy to reduce static loads on the wall. This study employed a finite difference analysis using a 2-D FLAC computer program by considering yielding and nonyielding states for retaining walls to explore the effectiveness of geofoam panels in improving the static performance of cantilever retaining walls. Retaining walls at heights of 3, 6, and 9 meters and geofoam panels with densities of 15, 20, and 25 (kg/m3 at three relative thicknesses of t/H = 0.05, 0.2, and 0.4 were modelled in this numerical study. In addition, the performance of the double EPS buffer system, which involves two vertical geofoam panels, in retaining walls’ stability with four panel spacing (50, 100, 150, and 200 cm was also evaluated in this research. The results showed that use of EPS15 with density equal to 15 (kg/m3 which has the lowest density among other geofoam panels has a significant role in reduction of lateral stresses, although the performance of geofoam in nonyielding retaining walls is better than yielding retaining walls.

  10. The Mechanical Properties of a Wall-Climbing Caterpillar Robot: Analysis and Experiment

    Directory of Open Access Journals (Sweden)

    Kun Wang


    Full Text Available This paper builds the kinematic model of a wall-climbing caterpillar robot to reveal the validity and the benefits of the closed-chain kinematics of the four-linkage mechanism to a crawling gait. The caterpillar robot can climb on a vertical wall by coordinating the rotations of one active joint and three passive joints. The mechanical property of the closed-chain kinematics of the four-linkage model is analysed. Furthermore, the relation between the driving joint torque and joint angle in the wall-climbing process is deduced based on the coplanar arbitrary force system. Afterwards, the joint control method is discussed in order to coordinate the rotation of the four joints so as to realize a reasonable wall climbing gait. To testify to the availability of the closed-chain four-linkage model, a wall-climbing caterpillar robot is developed with three different adhesion modules based on the vibrating suction method. A successful wall-climbing test confirms both the practicality of the four-linkage model and the validity of the adhesion modules based on the vibrating suction method. The results also show the reasonableness of the driving joint selection rule for ensuring a safe and reliable wall-climbing procedure.

  11. Wave trapping by dual porous barriers near a wall in the presence of bottom undulation (United States)

    Kaligatla, R. B.; Manisha; Sahoo, T.


    Trapping of oblique surface gravity waves by dual porous barriers near a wall is studied in the presence of step type varying bottom bed that is connected on both sides by water of uniform depths. The porous barriers are assumed to be fixed at a certain distance in front of a vertical rigid wall. Using linear water wave theory and Darcy's law for flow past porous structure, the physical problem is converted into a boundary value problem. Using eigenfunction expansion in the uniform bottom bed region and modified mild-slope equation in the varying bottom bed region, the mathematical problem is handled for solution. Moreover, certain jump conditions are used to account for mass conservation at slope discontinuities in the bottom bed profile. To understand the effect of dual porous barriers in creating tranquility zone and minimum load on the sea wall, reflection coefficient, wave forces acting on the barrier and the wall, and surface wave elevation are computed and analyzed for different values of depth ratio, porous-effect parameter, incident wave angle, gap between the barriers and wall and slope length of undulated bottom. The study reveals that with moderate porosity and suitable gap between barriers and sea wall, using dual barriers an effective wave trapping system can be developed which will exert less wave force on the barriers and the rigid wall. The proposed wave trapping system is likely to be of immense help for protecting various facilities/ infrastructures in coastal environment.

  12. Experimental and analytical investigation of the lateral load response of confined masonry walls

    Directory of Open Access Journals (Sweden)

    Hussein Okail


    Full Text Available This paper investigates the behavior of confined masonry walls subjected to lateral loads. Six full-scale wall assembles, consisting of a clay masonry panel, two confining columns and a tie beam, were tested under a combination of vertical load and monotonic pushover up to failure. Wall panels had various configurations, namely, solid and perforated walls with window and door openings, variable longitudinal and transverse reinforcement ratios for the confining elements and different brick types, namely, cored clay and solid concrete masonry units. Key experimental results showed that the walls in general experienced a shear failure at the end of the lightly reinforced confining elements after the failure of the diagonal struts formed in the brick wall due to transversal diagonal tension. Stepped bed joint cracks formed in the masonry panel either diagonally or around the perforations. A numerical model was built using the finite element method and was validated in light of the experimental results. The model showed acceptable correlation and was used to conduct a thorough parametric study on various design configurations. The conducted parametric study involved the assessment of the load/displacement response for walls with different aspect ratios, axial load ratios, number of confining elements as well as the size and orientation of perforations. It was found that the strength of the bricks and the number of confining elements play a significant role in increasing the walls’ ultimate resistance and displacement ductility.

  13. Studying boundary elements’ behaviour using masonry walls built with high-resistance bricks

    Directory of Open Access Journals (Sweden)

    Juan Carlos Restrepo Mejía


    Full Text Available This research was aimed at studying the behaviour of masonry walls built with and without boundary elements at both ends when sublected to monotonic and cyclic lateral loads. The walls were designed to have the greatest resistance, following NSR-98 recommendations (normas Colombianas de diseno y construcción sismo resistente, except for shear reinforcement. XTRACT software was used for finding axial load cf bending moment and curvature cf bending moment curves. One monotonic test and two cyclic tests were performed for each type of wall. Experimental results from the walls’ lateral load cf displacement curves were used for determining their ability to dissipate energy on an inelastic range (“R” force-reduction factor for seismic loads and displacement and curvature malleability. It was found that walls built without boundary elements suffered shear failure with cracks in a stepped configuration along the bricks’ edge. The type of failure for walls built with boundary elements was shear failure in the central panel with cracks in a stepped configuration, in addition to compression failure at the edge of the boundary elements with vertical cracks on the lower part of the wall and at the contact between the wall and the boundary element. Comparison with two other studies carried out at the Universidad Nacional showed similar cyclic behaviour, regardless of the clay brick’s strength. The “R” values obtained for both types of walls were lower than the recommended values given by NSR-98. It was determined that walls having boundary element have greater displacement malleability than walls without boundary elements.

  14. Studying boundary elements’ behaviour using masonry walls built with high-resistance bricks

    Directory of Open Access Journals (Sweden)

    Juan Carlos Restrepo Mejía


    Full Text Available This research was aimed at studying the behaviour of masonry walls built with and without boundary elements at both ends when sublected to monotonic and cyclic lateral loads. The walls were designed to have the greatest resistance, following NSR-98 recommendations (normas Colombianas de diseno y construcción sismo resistente, except for shear reinforcement. XTRACT software was used for finding axial load cf bending moment and curvature cf bending moment curves. One monotonic test and two cyclic tests were performed for each type of wall. Experimental results from the walls’ lateral load cf displacement curves were used for determining their ability to dissipate energy on an inelastic range (“R” force-reduction factor for seismic loads and displacement and curvature malleability. It was found that walls built without boundary elements suffered shear failure with cracks in a stepped configuration along the bricks’ edge. The type of failure for walls built with boundary elements was shear failure in the central panel with cracks in a stepped configuration, in addition to compression failure at the edge of the boundary elements with vertical cracks on the lower part of the wall and at the contact between the wall and the boundary element. Comparison with two other studies carried out at the Universidad Nacional showed similar cyclic behaviour, regardless of the clay brick’s strength. The “R” values obtained for both types of walls were lower than the recommended values given by NSR-98. It was determined that walls having boundary element have greater displacement malleability than walls without boundary elements.

  15. Structural and Electrical Investigation of C60-Graphene Vertical Heterostructures. (United States)

    Kim, Kwanpyo; Lee, Tae Hoon; Santos, Elton J G; Jo, Pil Sung; Salleo, Alberto; Nishi, Yoshio; Bao, Zhenan


    Graphene, with its unique electronic and structural qualities, has become an important playground for studying adsorption and assembly of various materials including organic molecules. Moreover, organic/graphene vertical structures assembled by van der Waals interaction have potential for multifunctional device applications. Here, we investigate structural and electrical properties of vertical heterostructures composed of C60 thin film on graphene. The assembled film structure of C60 on graphene is investigated using transmission electron microscopy, which reveals a uniform morphology of C60 film on graphene with a grain size as large as 500 nm. The strong epitaxial relations between C60 crystal and graphene lattice directions are found, and van der Waals ab initio calculations support the observed phenomena. Moreover, using C60-graphene heterostructures, we fabricate vertical graphene transistors incorporating n-type organic semiconducting materials with an on/off ratio above 3 × 10(3). Our work demonstrates that graphene can serve as an excellent substrate for assembly of molecules, and attained organic/graphene heterostructures have great potential for electronics applications.

  16. Overlap/Domain-wall reweighting (United States)

    Fukaya, H.; Aoki, S.; Cossu, G.; Hashimoto, S.; Kaneko, T.; Noaki, J.

    We investigate the eigenvalues of nearly chiral lattice Dirac operators constructed with five-dimensional implementations. Allowing small violation of the Ginsparg-Wilson relation, the HMC simulation is made much faster while the eigenvalues are not significantly affected. We discuss the possibility of reweighting the gauge configurations generated with domain-wall fermions to those of exactly chiral lattice fermions.

  17. The Influence of Wall Binders

    DEFF Research Database (Denmark)

    Rose, Jørgen


    This report is an analysis of the thermal bridge effects that occur in wall binders in masonry buildings. The effects are analyzed using a numerical calculation programme.The results are compared to the values given in the danish standard, DS418....

  18. Retrofitting Systems for External Walls

    DEFF Research Database (Denmark)

    Rose, Jørgen


    In this report, 9 different external and internal retrofitting systems are analyzed using numerical calculations. The analysis focuses on the thermal bridge effects in the different systems, and on this basis it is discussed whether internal or external retrofitting has the most advantages....... The different systems are evaluated using 5 different types of existing walls....

  19. Acute traumatic abdominal wall hernia

    NARCIS (Netherlands)

    D. den Hartog (Dennis); W.E. Tuinebreijer (Wim); P.P. Oprel (Pim); P. Patka (Peter)


    textabstractAlthough blunt abdominal trauma is frequent, traumatic abdominal wall hernias (TAWH) are rare. We describe a large TAWH with associated intra-abdominal lesions that were caused by high-energy trauma. The diagnosis was missed by clinical examination but was subsequently revealed by a

  20. Fandom and the fourth wall

    Directory of Open Access Journals (Sweden)

    Jenna Kathryn Ballinger


    Full Text Available I use the Teen Wolf fandom as an example to examine the ways social media has created a more complicated, nuanced relationship with fans. The collapse of the fourth wall between fans and The Powers That Be can have both positive and negative impacts, depending on the willingness of participants to maintain mutual respect and engage in meaningful dialogue.