WorldWideScience

Sample records for multi-pane window wall

  1. Shielding effectiveness research of window panes in microwave frequency range

    OpenAIRE

    Bilotas, Evaldas

    2016-01-01

    The purpose of this work is to investigate microwave shielding effectiveness (SE) of modern window panes. In addition, it will be made sure of what is the main mechanism behind the electromagnetic shielding by investigating three different glasses reflection coefficient. In order to achieve these goals, shielding effectiveness of window panes and their components will be measured in semi-anechoic and anechoic chambers. Furthermore, these measurements will be done in near and far field conditi...

  2. Exhaled nitric oxide levels in school children in relation to IgE sensitisation and window pane condensation.

    Science.gov (United States)

    Janson, Christer; Kalm-Stephens, Pia; Foucard, Tony; Norbäck, Dan; Alving, Kjell; Nordvall, S Lennart

    2005-08-01

    A positive relation between exhaled nitric oxide (NO) levels and allergen exposure has been found in some studies whereas there is less information on how non-allergen environmental factors influences exhaled NO. To study the relationship between exhaled NO levels in schoolchildren in relation to IgE sensitisation and allergenic and non-allergenic environmental factors. This study comprised 374 schoolchildren (13-14 years of age) who performed exhaled NO-measurements and skin prick tests. Exposure to allergens, respiratory infections, environmental tobacco smoke and home window pane condensation, the latter an indicator of high humidity and poor ventilation was evaluated through questionnaires. In IgE-sensitised children sensitisation to pets was a more important determinant of exhaled NO than sensitisation to pollen. Higher NO levels were found in cat-sensitised children with a cat or other furred pets at home compared to cat-sensitised children without pets (geometric mean, 24.0 vs. 13.9 ppb, P=0.03). Significantly higher exhaled NO levels were found in non-sensitised children that reported having a cold (5.7 vs. 3.8 ppb, P<0.001) or lived in homes with window pane condensation (7.1 vs. 4.4 ppb, P=0.01) than in non-sensitised children without a cold and window pane condensation, respectively. These associations were not found in children that were sensitised to inhalation allergens. Allergen exposure seems to be the most important determinant for exhaled NO levels in IgE-sensitised children whereas in non-sensitised children NO levels were associated with respiratory infections and home window pane condensation.

  3. Theoretical vibro-acoustic modeling of acoustic noise transmission through aircraft windows

    Science.gov (United States)

    Aloufi, Badr; Behdinan, Kamran; Zu, Jean

    2016-06-01

    In this paper, a fully vibro-acoustic model for sound transmission across a multi-pane aircraft window is developed. The proposed model is efficiently applied for a set of window models to perform extensive theoretical parametric studies. The studied window configurations generally simulate the passenger window designs of modern aircraft classes which have an exterior multi-Plexiglas pane, an interior single acrylic glass pane and a dimmable glass ("smart" glass), all separated by thin air cavities. The sound transmission loss (STL) characteristics of three different models, triple-, quadruple- and quintuple-paned windows identical in size and surface density, are analyzed for improving the acoustic insulation performances. Typical results describing the influence of several system parameters, such as the thicknesses, number and spacing of the window panes, on the transmission loss are then investigated. In addition, a comparison study is carried out to evaluate the acoustic reduction capability of each window model. The STL results show that the higher frequencies sound transmission loss performance can be improved by increasing the number of window panels, however, the low frequency performance is decreased, particularly at the mass-spring resonances.

  4. Thermal performance of a double pane window with a solar control coating for warm climate of Mexico

    International Nuclear Information System (INIS)

    Xamán, J.; Jiménez-Xamán, C.; Álvarez, G.; Zavala-Guillén, I.; Hernández-Pérez, I.; Aguilar, J.O.

    2016-01-01

    Highlights: • Pseudo-transient thermal performance of a double pane window (DPW) was determined. • The DPW was analyzed each 5 s by a period from 8:00 to 18:00 h. • 57,600 computational runs were necessary and the additive correction multigrid was implemented. • Solar control coating (SCC) in a DPW reduces 1073.79 W/m 2 with respect to the DPW without SCC. • SCC is highly recommended in a DPW because it reduces a 53.88% of the amount of energy gained. - Abstract: The pseudo-transient thermal performance (each 5 s) of a double pane window without and with a solar control coating was determined numerically. The study considers warm climatic conditions (Mexico) and a period from 8:00 to 18:00 h. The effect of varying the indoor air temperature (15–30 °C); and the incident solar radiation and the outdoor air temperature as functions of time is analyzed. The simulations were done with a self-developed ForTran program and it was verified with results from the literature. To obtain the results, 57,600 computational runs were necessary. From the results, the double pane window with a solar control coating allows a smaller heat flux to enter into a room than the corresponding without a solar control coating. The solar control coating in double glass window reduces the amount of 1073.79 W h/m 2 with respect to the case without a solar control coating, which represents a reduction of 53.88% of the heat gain.

  5. Lighting energy savings potential of split-pane electrochromic windows controlled for daylighting with visual comfort

    Energy Technology Data Exchange (ETDEWEB)

    Software, Anyhere; Fernandes, Luis; Lee, Eleanor; Ward, Greg

    2013-03-15

    A simulation study was conducted to evaluate lighting energy savings of split-pane electrochromic (EC) windows controlled to satisfy key visual comfort parameters. Using the Radiance lighting simulation software, interior illuminance and luminance levels were computed for a south-facing private office illuminated by a window split into two independently-controlled EC panes. The transmittance of these was optimized hourly for a workplane illuminance target while meeting visual comfort constraints, using a least-squares algorithm with linear inequality constraints. Blinds were successively deployed until visual comfort criteria were satisfied. The energy performance of electrochromics proved to be highly dependent on how blinds were controlled. With hourly blind position adjustments, electrochromics showed significantly higher (62percent and 53percent, respectively without and with overhang) lighting energy consumption than clear glass. With a control algorithm designed to better approximate realistic manual control by an occupant, electrochromics achieved significant savings (48percent and 37percent, respectively without and with overhang). In all cases, energy consumption decreased when the workplace illuminance target was increased. In addition, the fraction of time during which the occupant had an unobstructed view of the outside was significantly greater with electrochromics: 10 months out of the year versus a handful of days for the reference case.

  6. Seasonal shading of walls with transparent thermal insulation by means of prismatic panes; Saisonale Abschattung von transparent gedaemmten Waenden mit Hilfe von Prismenscheiben

    Energy Technology Data Exchange (ETDEWEB)

    Christoffers, D.; Kneser, P.; Schramm, U. [Institut fuer Solarenergieforschung GmbH Hameln/Emmerthal (ISFH), Emmerthal (Germany). Abt. Systemtechnik von Solaranlagen

    1998-02-01

    Using prismatic panes, a seasonal shading responsive to the sun`s position can be realized. Thus the solar gains from direct radiation can be closely matched to the annual pattern of the heating requirements of buildings. The panes are suitable for window or facade elements in applications which do not need transparency insulated walls. The direct radiation received on a vertical south-oriented facade is reduced to 10% on clear summer days, while 90% is transmitted on clear winter days. The paper reports on results from computer simulations and experiences from a one year field test. (orig.) [Deutsch] Mit Hilfe von Prismenscheiben kann eine sonnenstandsabhaengige, saisonale Verschattung realisiert werden. Damit lassen sich solare Gewinne aus direkter Einstrahlung sehr gut an den jaehrlichen Verlauf des Heizenergiebedarfs von Gebaeuden anpassen. Sie eignen sich als nach Sueden weisende Fenster- und Fassadenelemente vorzugsweise in Bereichen, die keinen freien Durchblick benoetigen, insbesondere auch fuer transparent gedaemmte Solarwaende. Die auf die Suedfassade treffende Direktstrahlung wird durch die Prismenscheibe an klaren Wintertagen auf etwa 90%, an klaren Sommertagen auf 10% reduziert. Der Beitrag beschreibt die Ergebnisse von Simulationsrechnungen und die Erfahrungen aus einem einjaehrigen Praxistest. (orig.)

  7. Thermal bridges of modern windows

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan de Place; Møller, Eva B.; Nielsen, Anker

    2013-01-01

    if the window has an U-factor of 1 W/(m2·K) or lower. This paper describes the development of modern, energy efficient Danish windows with reduced thermal bridges. It focuses on materials, geometry, and sealing of window panes based on a literature review. Examples of modern windows are presented. Experience...... been an important driver for the development of new window solutions in Denmark, increasing the inner-surface temperature at the sealing of window panes. However, it will not stop complaints fromconsumers, as this temperature is calculated under standardized conditions. Increasing requirements...

  8. Evaluation of Energy Efficiency Performance of Heated Windows

    Science.gov (United States)

    Jammulamadaka, Hari Swarup

    The study about the evaluation of the performance of the heated windows was funded by the WVU Research Office as a technical assistance award at the 2014 TransTech Energy Business Development Conference to the Green Heated Glass company/project owned by Frank Dlubak. The award supports a WVU researcher to conduct a project important for commercialization. This project was awarded to the WVU Industrial Assessment Center in 2015. The current study attempted to evaluate the performance of the heated windows by developing an experimental setup to test the window at various temperatures by varying the current input to the window. The heated double pane window was installed in an insulated box. A temperature gradient was developed across the window by cooling one side of the window using gel based ice packs. The other face of the window was heated by passing current at different wattages through the window. The temperature of the inside and outside panes, current and voltage input, room and box temperature were recorded, and used to calculate the apparent R-value of the window when not being heated vs when being heated. It has been concluded from the study that the heated double pane window is more effective in reducing heat losses by as much as 50% than a non-heated double pane window, if the window temperature is maintained close to the room temperature. If the temperature of the window is much higher than the room temperature, the losses through the window appear to increase beyond that of a non-heated counterpart. The issues encountered during the current round of experiments are noted, and recommendations provided for future studies.

  9. An Intelligent Window for Optimal Ventilation and Minimum Thermal Loss

    DEFF Research Database (Denmark)

    Mortensen, Lone Hedegaard; Rose, Jørgen; Liu, Mingzhe

    This report compares the simulation results of 12 window typologies for four countries on four selected days. The simulation results are used to select the window frame construction including glazing type and pane configuration.......This report compares the simulation results of 12 window typologies for four countries on four selected days. The simulation results are used to select the window frame construction including glazing type and pane configuration....

  10. HVI Ballistic Limit Charaterization of Fused Silica Thermal Pane

    Science.gov (United States)

    Bohl, William E.; Miller, Joshua E.; Christiansen, Eric L.; Deighton, Kevin.; Davis, Bruce

    2015-01-01

    The Orion spacecraft's windows are exposed to the micrometeroid and orbital debris (MMOD) space environments while in space as well as the Earth entry environment at the mission's conclusion. The need for a low-mass spacecraft window design drives the need to reduce conservatism when assessing the design for loss of crew due to MMOD impact and subsequent Earth entry. Therefore, work is underway at NASA and Lockheed Martin to improve characterization of the complete penetration ballistic limit of an outer fused silica thermal pane. Hypervelocity impact tests of the window configuration at up to 10 km/s and hydrocode modeling have been performed with a variety of projectile materials to enable refinement of the fused silica ballistic limit equation.

  11. HVI Ballistic Limit Characterization of Fused Silica Thermal Panes

    Science.gov (United States)

    Miller, J. E.; Bohl, W. D.; Christiansen, E. L.; Davis, B. A.; Deighton, K. D.

    2015-01-01

    Fused silica window systems are used heavily on crewed reentry vehicles, and they are currently being used on the next generation of US crewed spacecraft, Orion. These systems improve crew situational awareness and comfort, as well as, insulating the reentry critical components of a spacecraft against the intense thermal environments of atmospheric reentry. Additionally, these materials are highly exposed to space environment hazards like solid particle impacts. This paper discusses impact studies up to 10 km/s on a fused silica window system proposed for the Orion spacecraft. A ballistic limit equation that describes the threshold of perforation of a fuse silica pane over a broad range of impact velocities, obliquities and projectile materials is discussed here.

  12. Building America's Low-e Storm Window Adoption Program Plan (FY2014)

    Energy Technology Data Exchange (ETDEWEB)

    Cort, Katherine A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2013-12-23

    Low emissivity (low-e) storm windows/panels appear to hold promise for effectively reducing existing home heating, ventilation, and air-conditioning (HVAC) consumption. Due to the affordability of low-e storm windows and the large numbers of existing homes that have low-performing single-pane or double-pane clear windows, a tremendous opportunity exists to provide energy savings by transforming the low-e storm window market and increasing market adoption. This report outlines U.S. Department of Energy (DOE) Building America’s planned market transformation activities in support of low-e storm window adoption during fiscal year (FY) 2014.

  13. Assessment of Energy Impact of Window Technologies for Commercial Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Tianzhen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division; Selkowitz, Stephen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division; Yazdanian, Mehry [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division

    2009-10-01

    Windows play a significant role in commercial buildings targeting the goal of net zero energy. This report summarizes research methodology and findings in evaluating the energy impact of windows technologies for commercial buildings. The large office prototypical building, chosen from the DOE commercial building benchmarks, was used as the baseline model which met the prescriptive requirements of ASHRAE Standard 90.1-2004. The building simulations were performed with EnergyPlus and TMY3 weather data for five typical US climates to calculate the energy savings potentials of six windows technologies when compared with the ASHRAE 90.1-2004 baseline windows. The six windows cover existing, new, and emerging technologies, including ASHRAE 189.1 baseline windows, triple pane low-e windows, clear and tinted double pane highly insulating low-e windows, electrochromic (EC) windows, and highly insulating EC windows representing the hypothetically feasible optimum windows. The existing stocks based on average commercial windows sales are included in the analysis for benchmarking purposes.

  14. 14 CFR 25.775 - Windshields and windows.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Windshields and windows. 25.775 Section 25... § 25.775 Windshields and windows. (a) Internal panes must be made of nonsplintering material. (b.... (d) The design of windshields and windows in pressurized airplanes must be based on factors peculiar...

  15. Operational Windows for Dry-Wall and Wetted-Wall IFE Chambers

    International Nuclear Information System (INIS)

    Najmabadi, F.; Raffray, A.R.; Bromberg, L.

    2004-01-01

    The ARIES-IFE study was an integrated study of inertial fusion energy (IFE) chambers and chamber interfaces with the driver and target systems. Detailed analysis of various subsystems was performed parametrically to uncover key physics/technology uncertainties and to identify constraints imposed by each subsystem. In this paper, these constraints (e.g., target injection and tracking, thermal response of the first wall, and driver propagation and focusing) were combined to understand the trade-offs, to develop operational windows for chamber concepts, and to identify high-leverage research and development directions for IFE research. Some conclusions drawn in this paper are (a) the detailed characterization of the target yield and spectrum has a major impact on the chamber; (b) it is prudent to use a thin armor instead of a monolithic first wall for dry-wall concepts; (c) for dry-wall concepts with direct-drive targets, the most stringent constraint is imposed by target survival during the injection process; (d) for relatively low yield targets (<250 MJ), an operational window with no buffer gas may exist; (e) for dry-wall concepts with indirect-drive targets, a high buffer gas pressure would be necessary that may preclude propagation of the laser driver and require assisted pinch transport for the heavy-ion driver; and (f) generation and transport of aerosols in the chamber is the key feasibility issue for wetted-wall concepts

  16. Vibro-acoustic model of an active aircraft cabin window

    Science.gov (United States)

    Aloufi, Badr; Behdinan, Kamran; Zu, Jean

    2017-06-01

    This paper presents modeling and design of an active structural acoustic control (ASAC) system for controlling the low frequency sound field transmitted through an aircraft cabin window. The system uses stacked piezoelectric elements arranged in a manner to generate out-of-plane actuation point forces acting on the window panel boundaries. A theoretical vibro-acoustic model for an active quadruple-panel system is developed to characterize the dynamic behavior of the system and achieve a good understanding of the active control performance and the physical phenomena of the sound transmission loss (STL) characteristics. The quadruple-panel system represents the passenger window design used in some classes of modern aircraft with an exterior double pane of Plexiglas, an interior dust cover pane and a glazed dimmable pane, all separated by thin air cavities. The STL characteristics of identical pane window configurations with different piezoelectric actuator sets are analyzed. A parametric study describes the influence of important active parameters, such as the input voltage, number and location of the actuator elements, on the STL is investigated. In addition, a mathematical model for obtaining the optimal input voltage is developed to improve the acoustic attenuation capability of the control system. In general, the achieved results indicate that the proposed ASAC design offers a considerable improvement in the passive sound loss performance of cabin window design without significant effects, such as weight increase, on the original design. Also, the results show that the acoustic control of the active model with piezoelectric actuators bonded to the dust cover pane generates high structural vibrations in the radiating panel (dust cover) and an increase in sound power radiation. High active acoustic attenuation can be achieved by designing the ASAC system to apply active control forces on the inner Plexiglas panel or dimmable panel by installing the actuators on the

  17. Field Evaluation of Highly Insulating Windows in the Lab Homes: Winter Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Parker, Graham B.; Widder, Sarah H.; Bauman, Nathan N.

    2012-06-01

    This field evaluation of highly insulating windows was undertaken in a matched pair of 'Lab Homes' located on the Pacific Northwest National Laboratory (PNNL) campus during the 2012 winter heating season. Improving the insulation and solar heat gain characteristics of a home's windows has the potential to significantly improve the home's building envelope and overall thermal performance by reducing heat loss (in the winter), and cooling loss and solar heat gain (in the summer) through the windows. A high quality installation and/or window retrofit will also minimize or reduce air leakage through the window cavity and thus also contribute to reduced heat loss in the winter and cooling loss in the summer. These improvements all contribute to decreasing overall annual home energy use. Occupant comfort (non-quantifiable) can also be increased by minimizing or eliminating the cold 'draft' (temperature) many residents experience at or near window surfaces that are at a noticeably lower temperature than the room air temperature. Lastly, although not measured in this experiment, highly insulating windows (triple-pane in this experiment) also have the potential to significantly reduce the noise transmittance through windows compared to standard double-pane windows. The metered data taken in the Lab Homes and data analysis presented here represent 70 days of data taken during the 2012 heating season. As such, the savings from highly insulating windows in the experimental home (Lab Home B) compared to the standard double-pane clear glass windows in the baseline home (Lab Home A) are only a portion of the energy savings expected from a year-long experiment that would include a cooling season. The cooling season experiment will take place in the homes in the summer of 2012, and results of that experiment will be reported in a subsequent report available to all stakeholders.

  18. Multi-objective optimization of linear multi-state multiple sliding window system

    International Nuclear Information System (INIS)

    Konak, Abdullah; Kulturel-Konak, Sadan; Levitin, Gregory

    2012-01-01

    This paper considers the optimal element sequencing in a linear multi-state multiple sliding window system that consists of n linearly ordered multi-state elements. Each multi-state element can have different states: from complete failure up to perfect functioning. A performance rate is associated with each state. The failure of type i in the system occurs if for any i (1≤i≤I) the cumulative performance of any r i consecutive elements is lower than w i . The element sequence strongly affects the probability of any type of system failure. The sequence that minimizes the probability of certain type of failure can provide high probability of other types of failures. Therefore the optimization problem for the multiple sliding window system is essentially multi-objective. The paper formulates and solves the multi-objective optimization problem for the multiple sliding window systems. A multi-objective Genetic Algorithm is used as the optimization engine. Illustrative examples are presented.

  19. Impact of window selection on the energy performance of residential buildings in South Korea

    International Nuclear Information System (INIS)

    Ihm, Pyeongchan; Park, Lyool; Krarti, Moncef; Seo, Donghyun

    2012-01-01

    With rapidly increasing energy consumption attributed to residential buildings in South Korea, there is a need to update requirements of the building energy code in order to improve the energy performance of buildings. This paper provides some guidelines to improve the building energy code to better select glazing types that minimize total energy use of residential buildings in Korea. In particular, detailed energy simulation analyses coupled with economical and environmental assessments are carried out to assess the thermal, economical, and environmental impacts of glazing thermal characteristics as well as window sizes associated with housing units in various representative climates within South Korea. The results of the analyses have clearly indicated that selecting glazing with low solar heat gain coefficient is highly beneficial especially for large windows and for mild climates. In particular, it is found that using any double-pane low-e glazing would provide better performance for windows in residential buildings than the clear double-pane glazing, currently required by the Korean building energy code. - Highlights: ► Results show that windows can be energy neutral for residential buildings. ► In Korea, double-pane low-e glazing would provide better energy performance. ► Double low-e clear filled with argon gas glazing is the most cost-effective.

  20. INTEGRATED ENERGY EFFICIENT WINDOW-WALL SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Michael Arney, Ph.D.

    2002-12-31

    The building industry faces the challenge of reducing energy use while simultaneously improving construction methods and marketability. This paper describes the first phase of a project to address these concerns by designing an Integrated Window Wall System (IWWS) that can be commercialized. This work builds on previous research conducted during the 1990's by Lawrence Berkeley national Laboratories (LBNL). During this phase, the objective was to identify appropriate technologies, problems and issues and develop a number of design concepts. Four design concepts were developed into prototypes and preliminary energy analyses were conducted Three of these concepts (the foam wall, steel wall, and stiffened plate designs) showed particular potential for meeting the project objectives and will be continued into a second phase where one or two of the systems will be brought closer to commercialization.

  1. Airtightness of the window-wall interface in masonry brick walls

    OpenAIRE

    Van Den Bossche, Nathan; Huyghe, Willem; Moens, Jan; Janssens, Arnold

    2013-01-01

    In recent decades there has been an increased focus on enhanced thermal resistance of building components and as a consequence, the relative importance of airtightness on the overall energy losses of buildings has increased significantly. The construction industry requires practical information on the airtightness of individual construction elements and building envelope interfaces. A literature review on the airtightness of window-wall interfaces has shown that no experimental data are avai...

  2. High Reliability R-10 Windows Using Vacuum Insulating Glass Units

    Energy Technology Data Exchange (ETDEWEB)

    Stark, David

    2012-08-16

    The objective of this effort was for EverSealed Windows (“EverSealed” or “ESW”) to design, assemble, thermally and environmentally test and demonstrate a Vacuum Insulating Glass Unit (“VIGU” or “VIG”) that would enable a whole window to meet or exceed the an R-10 insulating value (U-factor ≤ 0.1). To produce a VIGU that could withstand any North American environment, ESW believed it needed to design, produce and use a flexible edge seal system. This is because a rigid edge seal, used by all other know VIG producers and developers, limits the size and/or thermal environment of the VIG to where the unit is not practical for typical IG sizes and cannot withstand severe outdoor environments. The rigid-sealed VIG’s use would be limited to mild climates where it would not have a reasonable economic payback when compared to traditional double-pane or triple-pane IGs. ESW’s goals, in addition to achieving a sufficiently high R-value to enable a whole window to achieve R-10, included creating a VIG design that could be produced for a cost equal to or lower than a traditional triple-pane IG (low-e, argon filled). ESW achieved these goals. EverSealed produced, tested and demonstrated a flexible edge-seal VIG that had an R-13 insulating value and the edge-seal system durability to operate reliably for at least 40 years in the harshest climates of North America.

  3. The space station window observational research facility; a high altitude imaging laboratory

    International Nuclear Information System (INIS)

    Runco, Susan K.; Eppler, Dean B.; Scott, Karen P.

    1999-01-01

    Earth Science will be one of the major research areas to be conducted on the International Space Station. The facilities from which this research will be accomplished are currently being constructed and will be described in this paper. By April 1999, the International Space Station nadir viewing research window fabrication will be completed and ready for installation. The window will provide a 20 inch (51 cm) diameter clear aperture. The three fused silica panes, which make up the window are fabricated such that the total peak-to-valley wavefront error in transmission through the three panes over any six inch diameter aperture does not exceed λ/7 where the reference wavelength is 632.8 nm. The window will have over 90% transmission between about 400 and 750, above 50% transmission between about 310 nm and 1375 nm and 40% transmission between 1386 nm and 2000 nm. The Window Operational Research Facility (WORF) is designed to accommodate payloads using this research window. The WORF will provide access to the International Space Station utilities such as data links, temperature cooling loops and power. Emphasis has been placed on the factors which will make this facility an optimum platform for conducting Earth science research

  4. PROCESS AND APPARATUS FOR SEPARATING INDIVIDUAL PANES FROM A LAMINATED GLASS SHEET

    OpenAIRE

    Kübler, R.; Rist, T.; Hoetger, B.

    2011-01-01

    The invention relates to a process for separating at least one individual pane of predefined size and edge form from a laminated glass sheet, which has at least two laminated glass sheet panes which are arranged one above another in adjacent form and between which there is arranged a plastic film, which permanently bonds the laminated glass sheet panes to one another, wherein - a laser track channel which at least weakens the plastic structure of the plastic film is laid into the plastic film...

  5. In Plane Loaded Glass Panes in Façades, Temperature Loads in Fixed Bonded Glass Panes

    NARCIS (Netherlands)

    Huveners, E.M.P.; Herwijnen, van F.; Soetens, F.; Hofmeyer, H.; Vitkala, J.

    2005-01-01

    The author discusses the use of glass panes as transparent stability elements in vertical façade structures subjected to in-plane loads including temperature loads. In the present façade architecture, glass is normally used non-structural. The only mechanical requirement is to resist transversal

  6. Cambios microestructurales y reológicos de masas y panes sin gluten

    OpenAIRE

    Rivera Flores, José Octavio

    2015-01-01

    El estudio de la microestructura de las masas y panes sin gluten nos permite predecir el comportamiento de estos durante los procesos de elaboración y por ende la maquinabilidad de los mismos. Se hizo un análisis reológico de masas sin gluten y un análisis de perfil de textura (TPA) a los panes elaborados a partir de estas, también se tomaron imágenes por medio del microscopio electrónico de barrido, tanto de las masas como de los panes. Para hacer el perfil reológico se hicieron ensayos osci...

  7. Multi-scale window specification over streaming trajectories

    Directory of Open Access Journals (Sweden)

    Kostas Patroumpas

    2013-12-01

    Full Text Available Enormous amounts of positional information are collected by monitoring applications in domains such as fleet management, cargo transport, wildlife protection, etc. With the advent of modern location-based services, processing such data mostly focuses on providing real-time response to a variety of user requests in continuous and scalable fashion. An important class of such queries concerns evolving trajectories that continuously trace the streaming locations of moving objects, like GPS-equipped vehicles, commodities with RFID's, people with smartphones etc. In this work, we propose an advanced windowing operator that enables online, incremental examination of recent motion paths at multiple resolutions for numerous point entities. When applied against incoming positions, this window can abstract trajectories at coarser representations towards the past, while retaining progressively finer features closer to the present. We explain the semantics of such multi-scale sliding windows through parameterized functions that reflect the sequential nature of trajectories and can effectively capture their spatiotemporal properties. Such window specification goes beyond its usual role for non-blocking processing of multiple concurrent queries. Actually, it can offer concrete subsequences from each trajectory, thus preserving continuity in time and contiguity in space along the respective segments. Further, we suggest language extensions in order to express characteristic spatiotemporal queries using windows. Finally, we discuss algorithms for nested maintenance of multi-scale windows and evaluate their efficiency against streaming positional data, offering empirical evidence of their benefits to online trajectory processing.

  8. Mauritius green building handbook, vol 1: Building envelope

    CSIR Research Space (South Africa)

    Van Wyk, Llewellyn V

    2010-08-01

    Full Text Available of the load- and non-load-bearing walls, including all doors and windows. Walls A wall is a continuous, usually vertical structure that is thin relative to its length and height (Emmitt & Gorse, 2005). Apart from functioning as structural elements... of thermal insulation, the greater the effect of thermal bridging (Emmitt & Gorse, 2005). Areas where thermal bridging typically occurs is through single pane glazing, metal door and window frames, solid masonry sections (window and door heads and sills...

  9. Construction of concrete hot cells; requirements for shielding windows for concrete walls with different densities

    International Nuclear Information System (INIS)

    1987-10-01

    The shielding windows form part of the basic equipment of hot cells for remote handling, as defined in standard DIN 25 420 part 1. The draft standard in hand is intended to specify the design and manufacture requirements, especially with regard to main dimensions, sight quality, shielding effects, and radiation resistance. The standard refers to three types of shielding window with surface area design (product of density and wall thickness) corresponding to concrete walls of the densities 2.4, 3.4, and 4.0 g/cm 3 . The windows fit to three types of concrete of common usage, and the design is made for Co-60 radiation, with attenuation factors of about 10 4 , 10 6 , or 10 7 . For concrete walls with densities between these data, a shielding window suitable to the next higher density data is to be chosen. (orig./HP) [de

  10. Through the looking glass and back again: the PANE case, a rebuttal

    International Nuclear Information System (INIS)

    Bauser, D.B.

    1985-01-01

    The Supreme Court rejected the proposition that a federal agency is required to assess the psychological health aspects of a federal project in Metropolitan Edison Co. v. People Against Nuclear Energy (PANE). The author challenges an earlier article by W. Jordan when he finds that the PANE decision establishes that the National Environmental Policy Act (NEPA) does not require this kind of assessment. After reviewing the PANE case, he concludes that Jordan was incorrect in suggesting that the Court's decision was narrow in scope and that psychological distress would be a cognizable environmental impact under NEPA in many cases. The author agrees that psychological harm may well affect the quality of modern life, but it is not within the scope of NEPA

  11. Reinforcement mechanism of multi-anchor wall with double wall facing

    Science.gov (United States)

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

    2017-10-01

    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.

  12. 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

    2007-11-01

    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.

  13. Heat transport and solar transmission through a window system with low-emitting coatings

    Energy Technology Data Exchange (ETDEWEB)

    Karlsson, B; Ribbing, C G

    1977-12-01

    Heat transfer processes through a double-glazed window system are examined. Network calculations show the good insulation properties of a double-glazed window system including at least one low-emitting film. When the insolation is taken into consideration, absorption in the panes change the heat-balance and a heat-transfer coefficient can not be defined. The thermal and optical properties of windows with low-emitting metallic films are investigated. These windows depress the heat-losses but show a relatively low solar transmission. They are suitable for reducing intense sunlight during the summer period, together with good thermal insulation during periods with low insolation.

  14. 76 FR 30653 - Aluminum Extrusions From the People's Republic of China: Countervailing Duty Order

    Science.gov (United States)

    2011-05-26

    ..., including, but not limited to, window frames, door frames, solar panels, curtain walls, or furniture. Such... glass pane and backing material, and solar panels. The scope also excludes finished goods containing...

  15. A Positive Affective Neuroendocrinology (PANE Approach to Reward and Behavioral Dysregulation

    Directory of Open Access Journals (Sweden)

    Keith eWelker

    2015-07-01

    Full Text Available Emerging lines of research suggest that both testosterone and maladaptive reward processing can modulate behavioral dysregulation. Yet to date, no integrative account has been provided that systematically explains neuroendocrine function, dysregulation of reward, and behavioral dysregulation in a unified perspective. This is particularly important given specific neuroendocrine systems are potential mechanisms underlying and giving rise to reward-relevant behaviors. In this review, we propose a forward thinking approach to study the mechanisms of reward and behavioral dysregulation from a positive affective neuroendocrinology (PANE perspective. This approach holds that testosterone increases reward processing, which increases the likelihood of behavioral dysregulation. Additionally, the PANE framework holds that reward processing mediates the effects of testosterone on behavioral dysregulation. We also explore sources of potential sex differences and the roles of age, cortisol, and individual differences within the PANE framework. Finally, we discuss future prospects for research questions and methodology in the emerging field of affective neuroendocrinology.

  16. Managing Vandalism in Day Secondary Schools in Zimbabwe ...

    African Journals Online (AJOL)

    Zimbabwe Journal of Educational Research ... contributing factors as leads to management strategies to reduce vandalism in day secondary schools. ... window panes, door handles, classroom furniture and writing on toilet walls and furniture.

  17. PV window - Development and demonstrations. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Haugaard, P.

    2011-05-15

    Using the results from the EU project RenewTransnet, which focused on the development of a pane with integrated solar cells, the goal of this project is to develop these principles into a window solution. This window solution is targeted to Danish building tradition and architecture. It is expected that an elegant PV-window solution for both new and retrofit buildings is developed during this project, and which appearance can be customized to each building. Based on results from a related projects carried out by Gaia Solar, the window solution will have the potential of being approximately 30% cheaper than similar products on the market. In this project this price reduction is the objective of the development of a window solution. The project team has succeeded in developing a 2-layer PV-window with glass / glass lamination with EVA as foil, which is 35% cheaper than similar products on the market. Since the price for the frame-profile does not differ significantly at market level, the price comparison is made on the basis of the developed PV-pane. The objective of 30 % price reduction in relation to similar products on the market is met. A special production process to the making glass/glass lamination with EVA as foil has been developed, in which a frame is put around the module which intends both to remove the unwanted tension along the edges, and to prevent the significant spillage of EVA from the module under pressure and prevent the invasive bubbles along the edge of module. Since the developed production method for making glass/glass modules with EVA is simple, a further cost reduction will primarily be in a reduction of the price of the cell. The project process has resulted in the development of a product, which due to continuous restrictions in the building regulations, will be very attractive in future buildings. (LN)

  18. Low-E Storm Windows Gain Acceptance as a Home Weatherization Measure

    Energy Technology Data Exchange (ETDEWEB)

    Gilbride, Theresa L.; Cort, Katherine A.

    2016-05-16

    This article for Home Energy Magazine describes work by the U.S. Department of Energy to develop low-emissivity storm windows as an energy efficiency-retrofit option for existing homes. The article describes the low-emissivity invisible silver metal coatings on the glass, which reflect heat back into the home in winter or back outside in summer and the benefits of low-e storm windows including insulation, air sealing, noise blocking, protection of antique windows, etc. The article also describes Pacific Northwest National Laboratory's efforts on behalf of DOE to overcome market barriers to adoption of the technology, including performance validation studies in the PNNL Lab Homes, cost effectiveness analysis, production of reports, brochures, how-to guides on low-e storm window installation for the Building America Solution Center, and a video posted on YouTube. PNNL's efforts were reviewed by the Pacific Northwest Regional Technical Forum (RTF), which serves as the advisory board to the Pacific Northwest Electric Power Planning Council and Bonneville Power Administration. In late July 2015, the RTF approved the low-e storm window measure’s savings and specifications, a critical step in integrating low-e storm windows into energy-efficiency planning and utility weatherization and incentive programs. PNNL estimates that more than 90 million homes in the United States with single-pane or low-performing double-pane windows would benefit from the technology. Low-e storm windows are suitable not only for private residences but also for small commercial buildings, historic properties, and facilities that house residents, such as nursing homes, dormitories, and in-patient facilities. To further assist in the market transformation of low-e storm windows and other high-efficiency window attachments, DOE helped found the window Attachment Energy Rating Council (AERC) in 2015. AERC is an independent, public interest, non-profit organization whose mission is to rate

  19. 77 FR 54900 - Aluminum Extrusions From the People's Republic of China: Final Results of Changed Circumstances...

    Science.gov (United States)

    2012-09-06

    ..., including, but not limited to, window frames, door frames, solar panels, curtain walls, or furniture. Such... glass or vinyl, picture frames with glass pane and backing material, and solar panels. The scope also...

  20. Adaptation, test-retest reliability, and construct validity of the Physical Activity Neighborhood Environment Scale in Nigeria (PANES-N).

    Science.gov (United States)

    Oyeyemi, Adewale L; Sallis, James F; Oyeyemi, Adetoyeje Y; Amin, Mariam M; De Bourdeaudhuij, Ilse; Deforche, Benedicte

    2013-11-01

    This study adapted the Physical Activity Neighborhood Environment Scale (PANES) to the Nigerian context and assessed the test-retest reliability and construct validity of the Nigerian version (PANESN). A multidisciplinary panel of experts adapted the original PANES to reflect the built and social environment of Nigeria. The adapted PANES was subjected to cognitive testing and test retest reliability in a diverse sample of Nigerian adults (N = 132) from different neighborhood types. Intraclass Correlation Coefficients (ICC) was used to assess test-retest reliability, and construct validity was investigated with Analysis of Covariance for differences in environmental attributes between neighborhoods. Four of the 17 items on the original PANES were significantly modified, 3 were removed and 2 new items were incorporated into the final version of adapted PANES-N. Test-retest reliability was substantial to almost perfect (ICC = 0.62-1.00) for all items on the PANES-N, and residents of neighborhoods in the inner city reported higher residential density, land use mix and safety, but lower pedestrian facilities and aesthetics than did residents of government reserved area/new layout neighborhoods. The PANES-N appears promising for assessing environmental perceptions related to physical activity in Nigeria, but further testing is required to assess its applicability across Africa.

  1. Examination of Relationship Between Photonic Signatures and Fracture Strength of Fused Silica Used in Orbiter Windows

    Science.gov (United States)

    Yost, William T.; Cramer, K. Elliott; Estes, Linda R.; Salem, Jonathan A.; Lankford, James, Jr.; Lesniak, Jon

    2011-01-01

    A commercially available grey-field polariscope (GFP) instrument for photoelastic examination is used to assess impact damage inflicted upon the outermost pane of the orbiter windows. Four categories of damage: hyper-velocity impacts that occur during space-flight (HVI); hypervelocity impacts artificially made at the Hypervelocity Impact Technology Facility (HIT-F); impacts made by larger objects falling onto the pane surface to simulate dropped items on the window during service/storage of vehicle (Bruises); and light scratches from dull objects designed to mimic those that might occur by dragging a dull object across the glass surface (Chatter Checks) are examined. The damage sites are cored from fused silica window carcasses, examined with the GFP and other methodologies, and broken using the ASTM Standard C1499-09 to measure the fracture strength. A correlation is made between the fracture strength and damage-site measurements including geometrical measurements and GFP measurements of photoelastic retardation (stress patterns) surrounding the damage sites. An analytical damage model to predict fracture strength from photoelastic retardation measurements is presented and compared with experimental results.

  2. Hot wire production of single-wall and multi-wall carbon nanotubes

    Science.gov (United States)

    Dillon, Anne C.; Mahan, Archie H.; Alleman, Jeffrey L.

    2010-10-26

    Apparatus (210) for producing a multi-wall carbon nanotube (213) may comprise a process chamber (216), a furnace (217) operatively associated with the process chamber (216), and at least one filament (218) positioned within the process chamber (216). At least one power supply (220) operatively associated with the at least one filament (218) heats the at least one filament (218) to a process temperature. A gaseous carbon precursor material (214) operatively associated with the process chamber (216) provides carbon for forming the multi-wall carbon nanotube (213). A metal catalyst material (224) operatively associated with the process (216) catalyzes the formation of the multi-wall carbon nanotube (213).

  3. Determination of Optimum Window to External Wall Ratio for Offices in a Hot and Humid Climate

    Directory of Open Access Journals (Sweden)

    Halil Alibaba

    2016-02-01

    Full Text Available Heat loss and gain through windows has a very high impact on the thermal comfort of offices. This paper analyzes a standard low energy consumption university office that has a standard envelope. Dynamic thermal simulations with EDSL Tas software, a predicted mean vote (PMV, and a predicted percentage of dissatisfied (PPD with all local discomfort as stated in ASHRAE, ISO 7730: 2005, EN 15251: 2007 were used for thermal sensation, in order to optimize the best window to external wall proportion in a hot and humid climate that exists in the Famagusta case study. A simulated office building is oriented east to west in order to take advantage of the wind direction. In May 45% (PPD < 6%–0.7% open window, 93% (PPD < 10–0.2 open window, and 97% (PPD < 15%–0.1% open window thermal comfort scores are obtained when the window to external wall ratio (WWR is 10%. In October 43% (PPD < 6%–0.7% open window, 86% (PPD < 10–0.2 open window, and 92% (PPD < 15%–0.1% open window thermal comfort scores are obtained when the WWR is 10%. In September 49% (PPD < 10% full open window and 51% (PPD < 15%–0.1% open window thermal comfort scores are obtained when the WWR is 10%.

  4. Psychological harm after PANE: NEPA's requirement to consider psychological damage

    International Nuclear Information System (INIS)

    Jordan, W.S. III

    1984-01-01

    In Metropolitan Edison Co. v. People Against Nuclear Energy (PANE), the Supreme Court held that the National Environmental Policy Act does not require the Nuclear Regulatory Commission (NRC) to consider the probable impact of its actions on psychological health. The Court's opinion, however, supports the conclusion that NEPA generally requires federal agencies to consider such probable impacts. This article examines the scope of federal responsibility following this decision. It delineates the causal relationship test that the Court adopted in PANE, and discusses possible obstacles to the consideration of psychological impacts under NEPA. It divides federal actions into four categories, then considers the benefits and burdens of the ruling using the NRC's responsibility to consider psychological health effects before licensing new nuclear reactors. 221 references

  5. PANeGOV : Understanding Democratic eGovernance in Asia | CRDI ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    As such, this research project is focussed on ICTs and "governance", which encompasses, but is not limited to, "e-government" services. PANeGOV will undertake 8 projects classified in three areas. All are research activities - intellectual investigations aimed at discovering, interpreting, revising and deepening our collective ...

  6. Impact Analysis of Window-Wall Ratio on Heating and Cooling Energy Consumption of Residential Buildings in Hot Summer and Cold Winter Zone in China

    Directory of Open Access Journals (Sweden)

    Qiaoxia Yang

    2015-01-01

    Full Text Available In order to assess the optimal window-wall ratio and the proper glazing type in different air conditioning system operation modes of residential buildings for each orientation in three typical cities in hot summer and cold winter zone: Chongqing, Shanghai, and Wuhan simulation models were built and analyzed using Designer’s Simulation Toolkit (DeST. The study analyzed the variation of annual heating energy demand, annual cooling energy demand, and the annual total energy consumption in different conditions, including different orientations, patterns of utilization of air conditioning system, window-wall ratio, and types of windows. The results show that the total energy consumption increased when the window-wall ratio is also increased. It appears more obvious when the window orientation is east or west. Furthermore, in terms of energy efficiency, low-emissivity (Low-E glass performs better than hollow glass. From this study, it can be concluded that the influence and sensitivity of window-wall ratio on the total energy consumption are related to the operation mode of air conditioning system, the orientation of outside window, and the glazing types of window. The influence of the factors can be regarded as reference mode for the window-wall ratio when designing residential buildings.

  7. Complex multimaterial insulating frames for windows with evacuated glazing

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Yueping; Eames, Philip C.; Hyde, Trevor J. [Centre for Sustainable Technologies, School of the Built Environment, University of Ulster, Newtownabbey, N. Ireland BT37 0QB (United Kingdom); Norton, Brian [Dublin Institute of Technology, Aungier Street, Dublin 2 (Ireland)

    2005-09-01

    The thermal performance of a complex multimaterial frame consisting of an exoskeleton framework and cavities filled with insulant materials enclosing an evacuated glazing was simulated using a two-dimensional finite element model and the results were validated experimentally using a guarded hot box calorimeter. The analysed 0.5m by 0.5m evacuated glazing consisted of two low-emittance film coated glass panes supported by an array of 0.32mm diameter pillars spaced 25mm apart, contiguously sealed by a 10mm wide metal edge seal. Thermal performance of windows employing evacuated glazing set in various complex multimaterial frames were analysed in detail. Very good agreement was found between simulations and experimental measurements of surface temperatures of the evacuated glazing window system. The heat loss from a window with an evacuated glazing and a complex multimaterial frame is about 80% of that for a window comprised of an evacuated glazing set in a single material solid frame. (author)

  8. Complex multimaterial insulating frames for windows with evacuated glazing

    Energy Technology Data Exchange (ETDEWEB)

    Yueping Fang; Eames, P.C.; Hyde, T.J. [University of Ulster, Newtonabbey (United Kingdom). Centre for Sustainable Technologies; Norton, B. [Dublin Institute of Technology, Dublin (Ireland)

    2005-09-01

    The thermal performance of a complex multimaterial frame consisting of an exoskeleton framework and cavities filled with insulant materials enclosing an evacuated glazing was simulated using a two-dimensional finite element model and the results were validated experimentally using a guarded hot box calorimeter. The analysed 0.5 m by 0.5 m evacuated glazing consisted of two low-emittance film coated glass panes supported by an array of 0.32 mm diameter pillars spaced 25 mm apart, contiguously sealed by a 10 mm wide metal edge seal. Thermal performance of windows employing evacuated glazing set in various complex multimaterial frames were analysed in detail. Very good agreement was found between simulations and experimental measurements of surface temperatures of the evacuated glazing window system. The heat loss from a window with an evacuated glazing and a complex multimaterial frame is about 80% of that for a window comprised of an evacuated glazing set in a single material solid frame. (author)

  9. Laboratory testing of joints between windows and highly insulated cavity walls. Investigations of tightness against rain and wind

    Energy Technology Data Exchange (ETDEWEB)

    Kjaer, A

    1983-10-01

    In the Danish energy research programme, 1EFP 80, a number of laboratory tests have been carried out on models of highly insulated cavity brick walls in order to study rain- and wind tightness of the joints between windows and such walls. Tests have been carried out with joints tightened only with a rain barrier as well as with joints according to the two stage joint principle. In the exterior part of the joint has in both cases been used a mortar, and expanding gasket, an EPDM-profile and wooden battens. Further an experiment has been carried out on a plastic window, where mastic was used as well in the exterior as the interior part of the joint. The findings were that a two-stage joint gives the best performance as well regarding air tightness as rain tightness. Further the experiments have shown that a window frame should have a depth of at least 90 mm in order to design a joint between window and wall, which is satisfactory as well regarding thermal insulation as resistance to rain and wind.

  10. DOE Zero Energy Ready Home Case Study: Boulder ZED Design Build - Boulder, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2014-11-01

    This case study describes a DOE Zero Energy Ready Home in Boulder, Colorado, that scored HERS 38 without PV and 0 with PV. This 2,504 ft2 custom home has advanced framed walls, superior insulation a ground-source heat pump, ERV, and triple-pane windows.

  11. Transparent aerogel Windows

    DEFF Research Database (Denmark)

    Jensen, Karsten Ingerslev; Schultz, Jørgen Munthe

    the supercritical washing step included in the drying phase. At the same time the production plant have been modified to recycle most of the chemicals involved in the production process. A large number of aerogel glazing prototypes have been made with partly evacuated aerogel in between two layers of low iron...... and anti reflection treated glass panes with an airtight edge seal solution based on multi-layered plastic foil developed for vacuum insulation purposes. The edge seal solution shows only a very limited thermal bridge effect. The final glazing has a total solar energy transmittance about 87% and a U...

  12. The selection of window width and levels for measuring the airway dimensions with spiral CT scan: an experimental study in Japanese white big-ear rabbits

    International Nuclear Information System (INIS)

    Han Xinwei; Lu Huuibing; Wu Gang; Ma Ji; Wang Nan; Si Jiangtao

    2009-01-01

    Objective: To investigate the optimal window width and window level for measuring the airway dimensions with spiral CT scan in Japanese white big-ear rabbits so as to lay the foundation for airway stenting in animal experiments. Methods: Multi-slice spiral CT scanning of cervico-thoracic region was performed in 30 healthy adult Japanese white big-ear rabbits, the anteroposterior and transversal diameter of the thoracic trachea, the anteroposterior diameter of the right and left bronchus were measured with lung window, mediastinum window and special fat window separately. The revealing rate of the tracheal wall and the measuring results in different windows and levels were recorded and compared with the anatomical data. The differences of the relevant data were statistically analyzed. Results: With lung window, the tracheal wall was well demonstrated, but the relevant data were smaller than that with mediastinum window. With mediastinum window, the data were bigger and the tracheal wall border appeared blurred. The results obtained with fat window were close to the actual anatomical data. Conclusion: For accurately measuring the anteroposterior and transversal diameter of the thoracic trachea in Japanese white big-ear rabbits with multi- slice spiral CT scan, fat window should be adopted, which is helpful for the preparation of tracheal and bronchial stents. (authors)

  13. Design and Verification of Critical Pressurised Windows for Manned Spaceflight

    Science.gov (United States)

    Lamoure, Richard; Busto, Lara; Novo, Francisco; Sinnema, Gerben; Leal, Mendes M.

    2014-06-01

    The Window Design for Manned Spaceflight (WDMS) project was tasked with establishing the state-of-art and explore possible improvements to the current structural integrity verification and fracture control methodologies for manned spacecraft windows.A critical review of the state-of-art in spacecraft window design, materials and verification practice was conducted. Shortcomings of the methodology in terms of analysis, inspection and testing were identified. Schemes for improving verification practices and reducing conservatism whilst maintaining the required safety levels were then proposed.An experimental materials characterisation programme was defined and carried out with the support of the 'Glass and Façade Technology Research Group', at the University of Cambridge. Results of the sample testing campaign were analysed, post-processed and subsequently applied to the design of a breadboard window demonstrator.Two Fused Silica glass window panes were procured and subjected to dedicated analyses, inspection and testing comprising both qualification and acceptance programmes specifically tailored to the objectives of the activity.Finally, main outcomes have been compiled into a Structural Verification Guide for Pressurised Windows in manned spacecraft, incorporating best practices and lessons learned throughout this project.

  14. Fabrication of a multi-walled metal pipe

    International Nuclear Information System (INIS)

    Shimamune, Koji; Toda, Saburo; Ishida, Ryuichi; Hatanaka, Tatsuo.

    1969-01-01

    In concentrically arranged metal pipes for simulated fuel elements in the form of a multi-walled pipe, their one end lengthens gradually in the axial direction from inner and outer pipes toward a central pipe for easy adjustment of deformation which occurs when the pipes are drawn. A plastic electrical insulator is disposed between adjacent pipes. Each end of the pipes is equipped with an annular flexible stopper which is allowed to travel in the axial direction so as to prevent the insulator from falling during drawing work. At the other end, all pipes are constricted and joined to each other to thereby form the desired multi-walled pipe. (Mikami, T.)

  15. Investigation of Different Configurations of a Ventilated Window to Optimize Both Energy Efficiency and Thermal Comfort

    DEFF Research Database (Denmark)

    Liu, Mingzhe; Heiselberg, Per; Larsen, Olena Kalyanova

    2017-01-01

    The study in this article investigates 15 ventilated window typologies with different pane configurations and glazing types in climates of four European countries (United Kingdom, Denmark, France and Germany) in order to identify the optimum typology with regard to their energy balance and impact...... on thermal comfort. Hourly simulations of the heat balances of the windows are conducted on four days representing different typical weather conditions according to the method described in EN ISO 13790. U and g values used in the calculation method are calculated in European software tool (WIS......) for the calculation of the thermal and solar properties of commercial and innovative window systems. Additionally, comfort performance is evaluated by inlet air temperature and internal surface temperature of the windows calculated by WIS software. The results of the study show the energy and comfort performance...

  16. The future 2015 Danish Building Regulations concerning energy performance of multi framed windows

    DEFF Research Database (Denmark)

    Hacksen Kampmann, Thomas

    The future Danish Building Regulation BR 2015 will reduce energy consumption within the overall building stock. Regarding the very important field windows, it seems that BR 2015 will be based on the same rules as today, except for a simple reduction of the limits for energy loss. Since a big part...... of the total amount of energy consumption in buildings is lost through windows, and the regulations concerning multi framed windows are already highly problematic today, there is a risk of the problem getting bigger in the future....

  17. Handling apparatus for fuel assemblies in a core

    International Nuclear Information System (INIS)

    Hatakenaka, Hideo.

    1975-01-01

    Object: To prevent an occurrence of a cloud as well as trouble in outflow of cooling water at the time of failure, in a window through which the operation of a collet installing and removing mechanism is monitored. Structure: A monitoring window comprises a pair of transparent window panes between which is interposed a non-compressive transparent fluid. With this construction, when the collet installing and removing mechanism within a container is operated while illuminating it by light means and monitoring it by a television camera to connect a fuel assembly with a shielding plug, and even if one transparent window pane should be failed as a result of trouble, the other transparent window pane prevents outflow of cooling water within a fuel transferring transfer port, and at the same time, the scattering force of fragments of failed transparent window pane is attenuated by the non-compressive transparent body within the monitoring window chamber. (Hanada, M.)

  18. Multi-walled carbon nanotubes integrated in microcantilevers for application of tensile strain

    DEFF Research Database (Denmark)

    Dohn, Søren; Kjelstrup-Hansen, Jakob; Madsen, D.N.

    2005-01-01

    variations in the response. Using a simple resistor model we estimate the expected conductance-strain response for a multi-walled carbon nanotube, and compare to our results on multi-walled carbon nanotubes as well as measurements by others on single-walled carbon nanotubes. Integration of nanotubes...

  19. The limits of postfigurative technique in Ignazio Silone's Pane e Vino ...

    African Journals Online (AJOL)

    Uno scrittore che ha usato questa tecnica è Ignazio Silone. Essa forma una parte vitale della struttura del suo romanzo del 1937, Pane e vino. Tuttavia ci sono fondamentali debolezze nell'uso di Silone della figura simbolica di Cristo, il che esemplifica la critica di tale tecnica espressa in generale, fra i tanti, da Liston Pope e ...

  20. Flexible transparent aerogels as window retrofitting films and optical elements with tunable birefringence

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Qingkun; Frazier, Allister W.; Zhao, Xinpeng; De La Cruz, Joshua A.; Hess, Andrew J.; Yang, Ronggui; Smalyukh, Ivan I.

    2018-06-01

    Experimental realization of optically transparent, mechanically robust and flexible aerogels has been a longstanding challenge, which limits their practical applications in energy-saving devices, such as thermally insulating films for enhancing energy efficiency of windows. The poor transparency precluded even hypothetical consideration of the possibility of birefringent aerogels. We develop birefringent and optically isotropic aerogels that combine properties of thermal super-insulation, mechanical robustness and flexibility, and transparency to visible-spectrum light. This unusual combination of physical properties is achieved by combining liquid crystalline self-organization of cellulose nanofibers with polysiloxane cross-linking and control of the nanoscale porosity to form hybrid organic-inorganic mesostructured aerogels. Potential applications of these inexpensive materials range from single pane window retrofitting to smart fabrics.

  1. DOE ZERH Case Study: Mantell-Hecathorn Builders, Shenandoah Circle, Durango, CO

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2015-09-01

    Case study of a DOE 2015 Housing Innovation Award winning custom home in the cold climate that got a HERS 50 without PV, or HERS 21 with PV, with 2x6 24” on center walls with R-13 ccsf plus 3.5” blown fiberglass, plus R-10 rigid exterior; R-22 ICF basement walls; vented attic with spray foam over top plates, R-65 blown fiberglass; 96 AFUE furnace, triple-pane windows, 80% LED.

  2. Experimental Study of Multi-Walled Composite Shell Fragments under Thermal Force Effects

    Directory of Open Access Journals (Sweden)

    L. P. Tairova

    2015-01-01

    Full Text Available Multi-walled composite shells are a relatively new prospective type of load carrying structures for rocket and space engineering. These CFRP structures are produced by injection and infusion methods and have several advantages in comparison with common structures such as stringer-frame, grid and sandwich structures with a light core. In particular, those have more structural parameters, which enable one to control mechanical properties of the structure, and this is important in designing the load carrying structures of different purpose.Presently, there are few national and foreign publications on experimental investigations of mechanical properties of multi-walled shells. That is why the objective of the paper is to conduct the experimental study of deformation and failure processes of a multi-walled panel both under steady-state heating and under unsteady-state one.The paper presents the results of two tests: (1 the study of deformation and failure modes under compression and complete heating up to a specified temperature and (2 validation of working capability of multi-walled samples under single-side heating and compression simulating a start and flight version of the “ Proton” launch vehicle.Experimental results have shown that average elastic properties of multi-walled samples slightly depend on temperature for the studied range (from room temperature up to 195C while strength properties considerably decrease with increasing temperature, and this is typical for CFRP structures under compression. However, under unsteady-state short-term heating the structure has a strength that exceeds the minimal necessary strength of load carrying structures of the “Proton” launch vehicle (the samples satisfy simulated start conditions of the “Proton” launch vehicle. This is because of a low heat conductivity of the multi-walled core: an unheated sheet holds a low temperature and high load carrying capacity.Obtained results can be used in

  3. Experimental and Numerical Research of the Thermal Properties of a PCM Window Panel

    Directory of Open Access Journals (Sweden)

    Martin Koláček

    2017-07-01

    Full Text Available This paper reports the experimental and simulation analysis of a window system incorporating Phase Change Materials (PCMs. In this study, the latent heat storage material is exploited to increase the thermal mass of the building component. A PCM-filled window can increase the possibilities of storage energy from solar radiation and reduce the heating cooling demand. The presented measurements were performed on a specific window panel that integrates a PCM. The PCM window panel consists of four panes of safety glass with three gaps, of which the first one contains a prismatic glass, the second a krypton gas, and the last one a PCM. New PCM window panel technology uses the placement of the PCM in the whole space of the window cavity. This technology improves the thermal performance and storage mass of the window panel. The results show the incongruent melting of salt hydrates and the high thermal inertia of the PCM window panel. The simulation data showed that the PCM window panel and the double glazing panel markedly reduced the peak temperature on the interior surface, reduced the air temperature inside the room, and also considerably improved the thermal mass of the building. This means that the heat energy entering the building through the panel is reduced by 66% in the summer cycle.

  4. The surface modifications of multi-walled carbon nanotubes for multi-walled carbon nanotube/poly(ether ether ketone) composites

    International Nuclear Information System (INIS)

    Cao, Zongshuang; Qiu, Li; Yang, Yongzhen; Chen, Yongkang; Liu, Xuguang

    2015-01-01

    Graphical abstract: Multi-walled carbon nanotube/poly(ether ether ketone) (MWCNT/PEEK) composites incorporating surface modified multi-walled carbon nanotubes (MWCNTs) as fillers were fabricated in a solution blending method in order to explore the dynamic mechanical and tribological properties of MWCNT/PEEK composites systematically. It is evident that surface modifications of MWCNTs have a significant impact on dispersibility of MWCNTs in PEEK, dynamic mechanical and tribological properties of MWCNT/PEEK composites. Typically, a clear effect of surface modifications of MWCNTs on tribological properties of MWCNT/PEEK composites was observed. A significant reduction in frictional coefficient of MWCNT/PEEK composites with the MWCNTs modified with ethanolamine has been achieved and the self-lubricating film on their worn surfaces was also observed. - Highlights: • The dispersibility of surface modified MWCNTs in PEEK has been studied. • MWCNTs modified with ethanolamine have showed a good dispersion in PEEK. • Surface modifications of MWCNTs have a significant impact on both dynamic mechanical and tribological properties of MWCNT/PEEK composites. - Abstract: The effects of surface modifications of multi-walled carbon nanotubes (MWCNTs) on the morphology, dynamic mechanical and tribological properties of multi-walled carbon nanotube/poly(ether ether ketone) (MWCNT/PEEK) composites have been investigated. MWCNTs were treated with mixed acids to obtain acid-functionalized MWCNTs. Then the acid-functionalized MWCNTs were modified with ethanolamine (named e-MWCNTs). The MWCNT/PEEK composites were prepared by a solution-blending method. A more homogeneous distribution of e-MWCNTs within the composites was found with scanning electron microscopy. Dynamic mechanical analysis demonstrated a clear increase in the storage modulus of e-MWCNT/PEEK composites because of the improved interfacial adhesion strength between e-MWCNTs and PEEK. Furthermore, the presence of e

  5. The surface modifications of multi-walled carbon nanotubes for multi-walled carbon nanotube/poly(ether ether ketone) composites

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Zongshuang [Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, Taiyuan University of Technology, Taiyuan 030024 (China); Research Center of Advanced Material Science and Technology, Taiyuan University of Technology, Taiyuan 030024 (China); Qiu, Li [Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, Taiyuan University of Technology, Taiyuan 030024 (China); College of Chemistry and Chemical Engineering, Taiyuan University of Technology, Taiyuan 030024 (China); Yang, Yongzhen, E-mail: yyztyut@126.com [Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, Taiyuan University of Technology, Taiyuan 030024 (China); Research Center of Advanced Material Science and Technology, Taiyuan University of Technology, Taiyuan 030024 (China); Chen, Yongkang, E-mail: y.k.chen@herts.ac.uk [Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, Taiyuan University of Technology, Taiyuan 030024 (China); University of Hertfordshire, School of Engineering and Technology, Hatfield, Hertfordshire AL10 9AB (United Kingdom); Liu, Xuguang [Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, Taiyuan University of Technology, Taiyuan 030024 (China); College of Chemistry and Chemical Engineering, Taiyuan University of Technology, Taiyuan 030024 (China)

    2015-10-30

    Graphical abstract: Multi-walled carbon nanotube/poly(ether ether ketone) (MWCNT/PEEK) composites incorporating surface modified multi-walled carbon nanotubes (MWCNTs) as fillers were fabricated in a solution blending method in order to explore the dynamic mechanical and tribological properties of MWCNT/PEEK composites systematically. It is evident that surface modifications of MWCNTs have a significant impact on dispersibility of MWCNTs in PEEK, dynamic mechanical and tribological properties of MWCNT/PEEK composites. Typically, a clear effect of surface modifications of MWCNTs on tribological properties of MWCNT/PEEK composites was observed. A significant reduction in frictional coefficient of MWCNT/PEEK composites with the MWCNTs modified with ethanolamine has been achieved and the self-lubricating film on their worn surfaces was also observed. - Highlights: • The dispersibility of surface modified MWCNTs in PEEK has been studied. • MWCNTs modified with ethanolamine have showed a good dispersion in PEEK. • Surface modifications of MWCNTs have a significant impact on both dynamic mechanical and tribological properties of MWCNT/PEEK composites. - Abstract: The effects of surface modifications of multi-walled carbon nanotubes (MWCNTs) on the morphology, dynamic mechanical and tribological properties of multi-walled carbon nanotube/poly(ether ether ketone) (MWCNT/PEEK) composites have been investigated. MWCNTs were treated with mixed acids to obtain acid-functionalized MWCNTs. Then the acid-functionalized MWCNTs were modified with ethanolamine (named e-MWCNTs). The MWCNT/PEEK composites were prepared by a solution-blending method. A more homogeneous distribution of e-MWCNTs within the composites was found with scanning electron microscopy. Dynamic mechanical analysis demonstrated a clear increase in the storage modulus of e-MWCNT/PEEK composites because of the improved interfacial adhesion strength between e-MWCNTs and PEEK. Furthermore, the presence of e

  6. Development of multi-channel high power rectangular RF window for LHCD system employing high temperature vacuum brazing technique

    International Nuclear Information System (INIS)

    Sharma, P K; Ambulkar, K K; Parmar, P R; Virani, C G; Thakur, A L; Joshi, L M; Nangru, S C

    2010-01-01

    A 3.7 GHz., 120 kW (pulsed), lower hybrid current drive (LHCD) system is employed to drive non-inductive plasma current in ADITYA tokamak. The rf power is coupled to the plasma through grill antenna and is placed in vacuum environment. A vacuum break between the pressurized transmission line and the grill antenna is achieved with the help of a multi (eight) channel rectangular RF vacuum window. The phasing between adjacent channels of 8-channel window (arranged in two rows) is important for launching lower hybrid waves and each channel should have independent vacuum window so that phase information is retained. The geometrical parameter of the grill antenna, like periodicity (9mm), channel dimensions (cross sectional dimension of 76mm x 7mm), etc. is to be maintained. These design constraint demanded a development of a multi channel rectangular RF vacuum window. To handle rf losses and thermal effects, high temperature vacuum brazing techniques is desired. Based on the above requirements we have successfully developed a multi channel rectangular rf vacuum window employing high temperature vacuum brazing technique. During the development process we could optimize the chemical processing parameters, brazing process parameters, jigs and fixtures for high temperature brazing and leak testing, etc. Finally the window is tested for low power rf performance using VNA. In this paper we would present the development of the said window in detail along with its mechanical, vacuum and rf performances.

  7. Development of multi-channel high power rectangular RF window for LHCD system employing high temperature vacuum brazing technique

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, P K; Ambulkar, K K; Parmar, P R; Virani, C G; Thakur, A L [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India); Joshi, L M; Nangru, S C, E-mail: pramod@ipr.res.i [Central Electronics Engineering Research Institute, Pilani, Rajasthan 333 031 (India)

    2010-02-01

    A 3.7 GHz., 120 kW (pulsed), lower hybrid current drive (LHCD) system is employed to drive non-inductive plasma current in ADITYA tokamak. The rf power is coupled to the plasma through grill antenna and is placed in vacuum environment. A vacuum break between the pressurized transmission line and the grill antenna is achieved with the help of a multi (eight) channel rectangular RF vacuum window. The phasing between adjacent channels of 8-channel window (arranged in two rows) is important for launching lower hybrid waves and each channel should have independent vacuum window so that phase information is retained. The geometrical parameter of the grill antenna, like periodicity (9mm), channel dimensions (cross sectional dimension of 76mm x 7mm), etc. is to be maintained. These design constraint demanded a development of a multi channel rectangular RF vacuum window. To handle rf losses and thermal effects, high temperature vacuum brazing techniques is desired. Based on the above requirements we have successfully developed a multi channel rectangular rf vacuum window employing high temperature vacuum brazing technique. During the development process we could optimize the chemical processing parameters, brazing process parameters, jigs and fixtures for high temperature brazing and leak testing, etc. Finally the window is tested for low power rf performance using VNA. In this paper we would present the development of the said window in detail along with its mechanical, vacuum and rf performances.

  8. Application of the multi-objective cross-entropy method to the vehicle routing problem with soft time windows

    Directory of Open Access Journals (Sweden)

    C Hauman

    2014-06-01

    Full Text Available The vehicle routing problem with time windows is a widely studied problem with many real-world applications. The problem considered here entails the construction of routes that a number of identical vehicles travel to service different nodes within a certain time window. New benchmark problems with multi-objective features were recently suggested in the literature and the multi-objective optimisation cross-entropy method is applied to these problems to investigate the feasibility of the method and to determine and propose reference solutions for the benchmark problems. The application of the cross-entropy method to the multi-objective vehicle routing problem with soft time windows is investigated. The objectives that are evaluated include the minimisation of the total distance travelled, the number of vehicles and/or routes, the total waiting time and delay time of the vehicles and the makespan of a route.

  9. Reactor scale modeling of multi-walled carbon nanotube growth

    International Nuclear Information System (INIS)

    Lombardo, Jeffrey J.; Chiu, Wilson K.S.

    2011-01-01

    As the mechanisms of carbon nanotube (CNT) growth becomes known, it becomes important to understand how to implement this knowledge into reactor scale models to optimize CNT growth. In past work, we have reported fundamental mechanisms and competing deposition regimes that dictate single wall carbon nanotube growth. In this study, we will further explore the growth of carbon nanotubes with multiple walls. A tube flow chemical vapor deposition reactor is simulated using the commercial software package COMSOL, and considered the growth of single- and multi-walled carbon nanotubes. It was found that the limiting reaction processes for multi-walled carbon nanotubes change at different temperatures than the single walled carbon nanotubes and it was shown that the reactions directly governing CNT growth are a limiting process over certain parameters. This work shows that the optimum conditions for CNT growth are dependent on temperature, chemical concentration, and the number of nanotube walls. Optimal reactor conditions have been identified as defined by (1) a critical inlet methane concentration that results in hydrogen abstraction limited versus hydrocarbon adsorption limited reaction kinetic regime, and (2) activation energy of reaction for a given reactor temperature and inlet methane concentration. Successful optimization of a CNT growth processes requires taking all of those variables into account.

  10. Evaluation of Building Energy Saving Through the Development of Venetian Blinds' Optimal Control Algorithm According to the Orientation and Window-to-Wall Ratio

    Science.gov (United States)

    Kwon, Hyuk Ju; Yeon, Sang Hun; Lee, Keum Ho; Lee, Kwang Ho

    2018-02-01

    As various studies focusing on building energy saving have been continuously conducted, studies utilizing renewable energy sources, instead of fossil fuel, are needed. In particular, studies regarding solar energy are being carried out in the field of building science; in order to utilize such solar energy effectively, solar radiation being brought into the indoors should be acquired and blocked properly. Blinds are a typical solar radiation control device that is capable of controlling indoor thermal and light environments. However, slat-type blinds are manually controlled, giving a negative effect on building energy saving. In this regard, studies regarding the automatic control of slat-type blinds have been carried out for the last couple of decades. Therefore, this study aims to provide preliminary data for optimal control research through the controlling of slat angle in slat-type blinds by comprehensively considering various input variables. The window area ratio and orientation were selected as input variables. It was found that an optimal control algorithm was different among each window-to-wall ratio and window orientation. In addition, through comparing and analyzing the building energy saving performance for each condition by applying the developed algorithms to simulations, up to 20.7 % energy saving was shown in the cooling period and up to 12.3 % energy saving was shown in the heating period. In addition, building energy saving effect was greater as the window area ratio increased given the same orientation, and the effects of window-to-wall ratio in the cooling period were higher than those of window-to-wall ratio in the heating period.

  11. Software for Allocating Resources in the Deep Space Network

    Science.gov (United States)

    Wang, Yeou-Fang; Borden, Chester; Zendejas, Silvino; Baldwin, John

    2003-01-01

    TIGRAS 2.0 is a computer program designed to satisfy a need for improved means for analyzing the tracking demands of interplanetary space-flight missions upon the set of ground antenna resources of the Deep Space Network (DSN) and for allocating those resources. Written in Microsoft Visual C++, TIGRAS 2.0 provides a single rich graphical analysis environment for use by diverse DSN personnel, by connecting to various data sources (relational databases or files) based on the stages of the analyses being performed. Notable among the algorithms implemented by TIGRAS 2.0 are a DSN antenna-load-forecasting algorithm and a conflict-aware DSN schedule-generating algorithm. Computers running TIGRAS 2.0 can also be connected using SOAP/XML to a Web services server that provides analysis services via the World Wide Web. TIGRAS 2.0 supports multiple windows and multiple panes in each window for users to view and use information, all in the same environment, to eliminate repeated switching among various application programs and Web pages. TIGRAS 2.0 enables the use of multiple windows for various requirements, trajectory-based time intervals during which spacecraft are viewable, ground resources, forecasts, and schedules. Each window includes a time navigation pane, a selection pane, a graphical display pane, a list pane, and a statistics pane.

  12. Ag-catalysed cutting of multi-walled carbon nanotubes

    International Nuclear Information System (INIS)

    La Torre, A; Rance, G A; Miners, S A; Lucas, C Herreros; Smith, E F; Giménez-López, M C; Khlobystov, A N; Fay, M W; Brown, P D; Zoberbier, T; Kaiser, U

    2016-01-01

    In this work, the cutting of carbon nanotubes is investigated using silver nanoparticles deposited on arc discharge multi-walled carbon nanotubes. The composite is subsequently heated in air to fabricate shortened multi-walled nanotubes. Complementary transmission electron microscopy and spectroscopy techniques shed light on the cutting mechanism. The nanotube cutting is catalysed by the fundamental mechanism based on the coordination of the silver atoms to the π-bonds of carbon nanotubes. As a result of the metal coordination, the strength of the carbon–carbon bond is reduced, promoting the oxidation of carbon at lower temperature when heated in air, or lowering the activation energy required for the removal of carbon atoms by electron beam irradiation, assuring in both cases the cutting of the nanotubes. (paper)

  13. Use of a bipolar microprocessor in a multi-window discriminator for a system studying reactor fuel pins

    International Nuclear Information System (INIS)

    Frueh, J.

    1977-01-01

    An automatic evaluation system for non-destructive reactor fuel rod analysis is described. The characteristic γ radiation of certain radioisotopes is measured, and the isotope concentration is derived from this. To determine the radioisotope concentration, a digital multi-window discriminator is installed in the system to isolate the desired γ lines from the total spectrum; in addition, background subtraction is carried out. The multi-window discriminator was constructed of bipolar bit-slice microprocessor modules. A microinstruction set of 4 basic commands was defined by which the functional sequences in the instrument were programmed. (orig.) [de

  14. Poly(ethylene-co-butylene) functionalized multi walled carbon nanotubes applied in polypropylene nanocomposites

    DEFF Research Database (Denmark)

    Daugaard, Anders Egede; Jankova Atanasova, Katja; Marín, Jose Manuel Roman

    2012-01-01

    A novel functionalized multi walled carbon nanotube (MWCNT) was prepared through grafting with α-azido-poly(ethylene-co-butylene) (PEB-N3). The PEB-N3 was prepared through a two step procedure and grafted onto an industrial grade multi walled carbon nanotube (MWCNT) through a highly efficient...

  15. DOE ZERH Case Study: TC Legend Homes, Bellingham Power House, Bellingham, WA

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2015-09-01

    Case study of a DOE 2015 Housing Innovation Award winning custom home in the marine climate that got HERS 34 without PV or HERS -12 with PV, with 6” SIP walls and 10” SIP roof; R-28 ICF around slab, R-20 rigid foam under slab; radiant floor heat and passive design; air-to-water heat pump COP 4.4; HRV; earth tube ventilation; triple-pane windows, 100% LED.

  16. DOE Zero Energy Ready Home Case Study: Durable Energy Builders - Houston, Texas

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2014-11-01

    This case study describes a DOE Zero Energy Ready Home in Houston, Texas, that scored HERS 39 without PV and HERS 29 with PV. This 5,947 ft2 custom home has 11.5-inch ICF walls. The attic is insulated along the roof line with 5 to 7 inches of open-cell spray foam. Most of the home's drinking water is supplied by a 11,500-gallon rainwater cistern. Hurricane strapping connects the roof to the walls. The triple-pane windows are impact resistant. The foundation is a raised slab.

  17. Multi-window dialogue system of data processing for experimental setup VASSILISSA in PAW environment

    International Nuclear Information System (INIS)

    Andreev, A.N.; Vakatov, D.V.; Veselski, M.; Eremin, A.V.; Ivanov, V.V.; Khasanov, A.M.

    1992-01-01

    Multi-window dialogue system for processing data acquired from experimental setup VASSILISSA is presented. The system provides friendly user's interface for experimental data conversion, selection and preparing for graphic analysis with PAW. 7 refs.; 5 figs.; 1 tab

  18. Significance of Shear Wall in Multi-Storey Structure With Seismic Analysis

    Science.gov (United States)

    Bongilwar, Rajat; Harne, V. R.; Chopade, Aditya

    2018-03-01

    In past decades, shear walls are one of the most appropriate and important structural component in multi-storied building. Therefore, it would be very interesting to study the structural response and their systems in multi-storied structure. Shear walls contribute the stiffness and strength during earthquakes which are often neglected during design of structure and construction. This study shows the effect of shear walls which significantly affect the vulnerability of structures. In order to test this hypothesis, G+8 storey building was considered with and without shear walls and analyzed for various parameters like base shear, storey drift ratio, lateral displacement, bending moment and shear force. Significance of shear wall has been studied with the help of two models. First model is without shear wall i.e. bare frame and other another model is with shear wall considering opening also in it. For modeling and analysis of both the models, FEM based software ETABS 2016 were used. The analysis of all models was done using Equivalent static method. The comparison of results has been done based on same parameters like base shear, storey drift ratio, lateral displacement, bending moment and shear force.

  19. Activity and stability studies of platinized multi-walled carbon nanotubes as fuel cell electrocatalysts

    DEFF Research Database (Denmark)

    Stamatin, Serban Nicolae; Borghei, Maryam; Dhiman, Rajnish

    2015-01-01

    A non-covalent functionalization for multi-walled carbon nanotubes has been used as an alternative to the damaging acid treatment. Platinum nanoparticles with similar particle size distribution have been deposited on the surface modified multi-walled carbon nanotubes. The interaction between...

  20. Efecto de la incorporación de fibras dietéticas en la calidad de panes para celíacos

    OpenAIRE

    Díaz Malmierca, Álvaro

    2013-01-01

    La investigación en la elaboración de panes sin gluten está muy avanzada, siendo el déficit en micronutrientes de estos productos uno de los problemas sobre el que se está centrando la investigación. Uno de los nutrientes más deficitarios, y que más problemas causa sobre la salud de los pacientes celíacos es la fibra dietética. En este estudio se ha investigado el efecto que produce la adición de un 10% de diferentes fibras sobre las características de los panes, la influencia ...

  1. Comparative Study of Two Daylighting Analysis Methods with Regard to Window Orientation and Interior Wall Reflectance

    Directory of Open Access Journals (Sweden)

    Yeo Beom Yoon

    2014-09-01

    Full Text Available The accuracy and speed of the daylighting analysis developed for use in EnergyPlus is better than its predecessors. In EnergyPlus, the detailed method uses the Split-flux algorithm whereas the DElight method uses the Radiosity algorithm. Many existing studies have addressed the two methods, either individually or compared with other daylight analysis methods like Ray tracing but still there is lack of detailed comparative study of these two methods. Our previous studies show that the Split-flux method overestimates the illuminance, especially for the areas away from the window. The Radiosity method has the advantage of accurately predicting this illuminance because of how it deals with the diffuse light. For this study, the EnergyPlus model, which has been calibrated using data measured in a real building in previous studies, has also been used. The calibrated model has a south oriented window only. This model is then used to analyze the interior illuminance inside the room for north, west and east orientation of the window by rotating the model and by changing the wall reflectance of the model with south oriented window. Direct and diffuse component of the illuminance as well as the algorithms have been compared for a detailed analysis.

  2. TEMPERATURE FIELDS IN THE ZONE OF CONNECTION BETWEEN WINDOW AND BUILDING ENVELOPE

    OpenAIRE

    V. V. Ivanov; A. N. Butenko; L. V. Karaseva

    2011-01-01

    Problem statement. To determine additional heat losses through window opening slopes, it is ne-cessary to calculate temperature fields of a wall in the zone of connection between window and building envelope. Two types of building envelopes are considered: solid brick wall and two-layer-wall of bricks and fiber foam concrete block interlayered with air.Results. The results obtained show the influence of a window on the temperature field of wall opening. Different types of wall structures are ...

  3. Multi-Detector CT Findings of Palpable Chest Wall Masses in Children: A Pictorial Essay

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chan Ho; Kim, Young Tong [Dept. of Radiology, Soonchunhyang University College of Medicine, Cheonan Hospital, Cheonan (Korea, Republic of); Hong, Hyun Sook [Dept. of Radiology, Soonchunhyang University College of Medicine, Bucheon Hospital, Bucheon (Korea, Republic of)

    2013-03-15

    A wide variety of diseases manifest as palpable chest wall masses in children. These include normal variation, congenital anomalies, trauma, infection, axillary lymphadenopathies, soft tissue tumors and bone tumors. Given that most of these diseases are associated with chest wall deformity, diagnosis is difficult by physical examination or ultrasonography alone. However, multi-detector CT with three dimensional reconstruction is useful in the characterization and differential diagnosis of palpable chest wall lesions. In this article, we review the spectrum of palpable chest wall diseases and illustrate their multi-detector CT presentation.

  4. Application of multi-walled carbon nanotubes to enhance anodic ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-12-15

    Dec 15, 2009 ... Key words: Multi-walled carbon nanotubes, microbial fuel cell, Enterobacter cloacae, ... Aldrich) was prepared in absolute ethanol (Hu et al., 2006; Tkac .... incorporated Eu3+ by voltammetry and electrochemical impedance.

  5. DOE ZERH Case Study: Clifton View Homes, Marine Drive and Port Hadlcok, Coupeville and Port Hadlock WA

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2015-09-01

    Case study of two DOE 2015 Housing Innovation Award winning custom homes in the marine climate that got HERS 39 and 38 without PV or HERS 2-12 and -9 with PV, with 6.5” SIP walls and 10.25” SIP roof; 11.75 ICF around slab, R-20 rigid foam under slab; radiant floor heat and passive design; air-to-water heatpump, fresh air intake with fan, triple-pane windows, 100% LED.

  6. Prediction Model for Impulsive Noise on Structures

    Science.gov (United States)

    2012-09-01

    integral,11,51 which is simply a convolution of the waveform with the impulse response:        t dFthtx 0  (4.11) Reference 39...All the windows considered herein are single pane windows. The higher surface weight and probable higher damping of double pane or laminated

  7. Optical Property Requirements for Glasses, Ceramics and Plastics in Spacecraft Window Systems

    Science.gov (United States)

    Estes, Lynda

    2011-01-01

    This is a preliminary draft of a standard published by the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) that is intended to provide uniform window optical design requirements in support of the development of human-rated spaceflight hardware. The material covered in this standard is based on data from extensive testing by the Advanced Sensing and Optical Measurement Branch at NASA Langley Research Center, and compiled into requirements format by the NASA JSC Structural Engineering Division. At the time of this initial document release, a broader technical community has not reviewed this standard. The technical content of this standard is primarily based on the Constellation Program Orion Crew Exploration Vehicle Window Optical Properties Requirements, CxP 72407, Baseline. Unlike other optical requirements documents available for human rated spacecraft, this document includes requirements that ensure functionality for windows that contain glass/ceramic and/or plastic window substrate materials. These requirements were derived by measuring the optical properties of fused silica and aluminosilicate glass window assemblies and ensuring that the performance of any window assembly that includes a plastic pane or panes will meet the performance level of the all-glass assemblies. The resulting requirements are based upon the performance and parameter metrology testing of a variety of materials, including glass, transparent ceramics, acrylics, and polycarbonates. In general, these requirements are minimum specifications for each optical parameter in order to achieve the function specified for each functional category, A through D. Because acrylic materials perform at a higher level than polycarbonates in the optics regime, and CxP/Orion is planning to use acrylic in the Orion spacecraft, these requirements are based heavily on metrology from that material. As a result, two of the current Category D requirements for plastics are cited in

  8. Preparation of Hydroxypropyl-β-cyclodextrin Cross-linked Multi-walled Carbon Nanotubes and Their Application in Enantioseparation of Clenbuterol

    Institute of Scientific and Technical Information of China (English)

    Yu Jingang; Huang Dushu; Huang Kelong; Hong Yong

    2011-01-01

    A method of cross-linking multi-walled carbon nanotubes by a nucleophilic substitution of brominated multi-walled carbon nanotubes using hydroxypropyl-β-cyclodextrin anions was studied. The modified multi-walled carbon nanotube samples were characterized using thermogravimetric analysis, energy-dispersive X-ray spectros-copy, transmission electron microscopy, scanning electron microscopy, Raman spectroscopy and Fourier transform infrared spectroscopy. The hydroxypropyi-β-cyclodextrin modified multi-walled carbon nanotubes were used as a chiral stationary phase additive for thin-layer chromatography to separate clenbuterol enantiomers, and the chiral separation factor was increased.

  9. Structure reconstruction of TiO2-based multi-wall nanotubes: first-principles calculations.

    Science.gov (United States)

    Bandura, A V; Evarestov, R A; Lukyanov, S I

    2014-07-28

    A new method of theoretical modelling of polyhedral single-walled nanotubes based on the consolidation of walls in the rolled-up multi-walled nanotubes is proposed. Molecular mechanics and ab initio quantum mechanics methods are applied to investigate the merging of walls in nanotubes constructed from the different phases of titania. The combination of two methods allows us to simulate the structures which are difficult to find only by ab initio calculations. For nanotube folding we have used (1) the 3-plane fluorite TiO2 layer; (2) the anatase (101) 6-plane layer; (3) the rutile (110) 6-plane layer; and (4) the 6-plane layer with lepidocrocite morphology. The symmetry of the resulting single-walled nanotubes is significantly lower than the symmetry of initial coaxial cylindrical double- or triple-walled nanotubes. These merged nanotubes acquire higher stability in comparison with the initial multi-walled nanotubes. The wall thickness of the merged nanotubes exceeds 1 nm and approaches the corresponding parameter of the experimental patterns. The present investigation demonstrates that the merged nanotubes can integrate the two different crystalline phases in one and the same wall structure.

  10. On Young's modulus of multi-walled carbon nanotubes

    Indian Academy of Sciences (India)

    WINTEC

    load transfer in nanocomposites. In the present work, CNT/Al ... calculations. The theoretical modulus of the graphene sheet is supposed to be 1060 GPa (Harris 2004). The reason why multi-walled nanotubes have a modulus > 1060 GPa (that of graphene sheet) is currently not understood. However, in the present paper, ...

  11. Novel fabrication of silica nanotubes using multi-walled carbon ...

    Indian Academy of Sciences (India)

    Administrator

    Abstract. Silica nanotubes were synthesized using multi-walled carbon nanotubes (MWCNTs) as template. The as-obtained samples were characterized by infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscope (FE–SEM) and photo-.

  12. Energy and Process Optimization Assessment at U.S. Army Installation in Germany: Keiserslautern Army Depot, Piermasens Army Depot, Katterbach Kaserne, Storck Barracks in Illesheim, and U.S. Army Garrison Wiesbaden Schools

    Science.gov (United States)

    2007-09-01

    translucent panels (sky- lights) running the length of the building, with a total area of 3520 sq ft (Figure 8 value and are also very dirty...Envelope Exterior Walls 1. Light concrete block (approximately 20 cm, insulation in between) + metal sheet cover with insulation; estimated U-value... Concrete slab with insulation (15 cm), estimated U-value 0.30 W/m2,K Windows Thermal panes with light metal frames, U-value is most probably >2.0 W

  13. Optical Characterization and Energy Simulation of Glazing for High-Performance Windows

    International Nuclear Information System (INIS)

    Jonsson, Andreas

    2010-01-01

    This thesis focuses on one important component of the energy system - the window. Windows are installed in buildings mainly to create visual contact with the surroundings and to let in daylight, and should also be heat and sound insulating. This thesis covers four important aspects of windows: antireflection and switchable coatings, energy simulations and optical measurements. Energy simulations have been used to compare different windows and also to estimate the performance of smart or switchable windows, whose transmittance can be regulated. The results from this thesis show the potential of the emerging technology of smart windows, not only from a daylight and an energy perspective, but also for comfort and well-being. The importance of a well functioning control system for such windows, is pointed out. To fulfill all requirements of modern windows, they often have two or more panes. Each glass surface leads to reflection of light and therefore less daylight is transmitted. It is therefore of interest to find ways to increase the transmittance. In this thesis antireflection coatings, similar to those found on eye-glasses and LCD screens, have been investigated. For large area applications such as windows, it is necessary to use techniques which can easily be adapted to large scale manufacturing at low cost. Such a technique is dip-coating in a sol-gel of porous silica. Antireflection coatings have been deposited on glass and plastic materials to study both visual and energy performance and it has been shown that antireflection coatings increase the transmittance of windows without negatively affecting the thermal insulation and the energy efficiency. Optical measurements are important for quantifying product properties for comparisons and evaluations. It is important that new measurement routines are simple and applicable to standard commercial instruments. Different systematic error sources for optical measurements of patterned light diffusing samples using

  14. Decoration of Multi-walled Carbon Nanotubes by Metal ...

    African Journals Online (AJOL)

    The powder patterns of the as-prepared and acid treated MWCNTs are shown by the XRD spectra. The TEM results show the microstructure of the multi-walled carbon nanotubes well decorated with metal nanoparticles (Cu, Fe, Ni) and metal oxides (CuO, Fe2O3, NiO), while the SEM show the surface morphology.

  15. Effect of amino acid-functionalized multi-walled carbon nanotubes ...

    Indian Academy of Sciences (India)

    In a single-step, rapid microwave-assisted process, multi-walled carbon nanotubes were functionalized by -valine amino acid. Formation of amino acid on nanotube surface was confirmed by Fourier transform-infrared spectroscopy, thermogravimetric analysis, X-ray diffraction, field emission scanning and transmission ...

  16. Nano-QSAR: Genotoxicity of Multi-Walled Carbon Nanotubes

    International Nuclear Information System (INIS)

    Toropova, A. P.; Toropov, A. A.; Rallo, R.; Leszczynska, D.; Leszczynski, J.

    2016-01-01

    The study was carried out to develop an efficient approach for prediction the genotoxicity of carbon nano tubes. The experimental data on the bacterial reverse mutation test (TA100) on multi-walled carbon nano tubes was collected from the literature and examined as an endpoint. By means of the optimal descriptors calculated with the Monte Carlo method a mathematical model of the endpoint was built up. The model is represented by a function of: (i) dose (μg/plate); (ii) metabolic activation (i.e. with S9 mix or without S9 mix); and (iii) two types of multi-walled carbon nano tubes. The above listed conditions were represented by so-called quasi-SMILES. Simplified molecular input-line entry system (SMILES) is a tool for representation of molecular structure. The quasi-SMILES is a tool to represent physicochemical and / or biochemical conditions for building up a predictive model. Thus, instead of well-known paradigm of predictive modeling “endpoint is a mathematical function of molecular structure” a fresh paradigm “endpoint is a mathematical function of available eclectic data (conditions) is suggested.

  17. Reduction of short wavelength reflectance of multi-wall carbon nanotubes through ultraviolet laser irradiation

    Science.gov (United States)

    Stephens, Michelle S.; Simonds, Brian J.; Yung, Christopher S.; Conklin, Davis; Livigni, David J.; Oliva, Alberto Remesal; Lehman, John H.

    2018-05-01

    Multi-wall carbon nanotube coatings are used as broadband, low-reflectance absorbers for bolometric applications and for stray light control. They are also used as high emittance blackbody radiators. Irradiation of single wall carbon nanotubes with ultraviolet (UV) laser light has been shown to remove amorphous carbon debris, but there have been few investigations of the interaction of UV light with the more complex physics of multi-wall carbon nanotubes. We present measurements of reflectance and surface morphology before and after exposure of multi-wall carbon nanotube coatings to 248 nm UV laser light. We show that UV exposure reduces the reflectivity at wavelengths below 600 nm and present modeling of the thermal cycling the UV exposure causes at the surface of the carbon nanotubes. This effect can be used to flatten the spectral shape of the reflectivity curve of carbon nanotube absorber coatings used for broadband applications. Finally, we find that the effect of UV exposure depends on the nanotube growth process.

  18. (PC12) cell lines to oxidized multi-walled carbon nanotubes

    African Journals Online (AJOL)

    EB

    Methods: The pristine multi-walled carbon nanotubes (p-MWCNTs) were ... characterize the MWCNTs. ..... South Africa and NRF Focus Area, Nanotechnology ... of carbon nanotubes in drug delivery. Current. Opinion in Chemical Biology, 2005 ...

  19. Collapse and stability of single- and multi-wall carbon nanotubes

    International Nuclear Information System (INIS)

    Xiao, J; Liu, B; Huang, Y; Zuo, J; Hwang, K-C; Yu, M-F

    2007-01-01

    The collapse and stability of carbon nanotubes (CNTs) have important implications for their synthesis and applications. While nanotube collapse has been observed experimentally, the conditions for the collapse, especially its dependence on tube structures, are not clear. We have studied the energetics of the collapse of single- and multi-wall CNTs via atomistic simulations. The collapse is governed by the number of walls and the radius of the inner-most wall. The collapsed structure is energetically favored about a certain diameter, which is 4.12, 4.96 and 5.76 nm for single-, double- and triple-wall CNTs, respectively. The CNT chirality also has a strong influence on the collapsed structure, leading to flat, warped and twisted CNTs, depending on the chiral angle

  20. Thermo-mechanical design windows for SiC/SiC composite first wall of A-SSTR2

    International Nuclear Information System (INIS)

    He Kaihui; Satoshi Nishio

    2002-01-01

    The finite element analysis and calculation is performed for the blanket first wall made of SiC/SiC composite material for Advanced Steady-state Tokamak Reactor 2, A-SSTR2, which is now conceptually designed in Naka Fusion Research Establishment, JAERI. Comparison analysis and design window is analyzed by using the finite element code ADINA 7.4. Through 2D calculation for various geometrical configurations and sensitive material properties, a fundamental guideline for first wall and blanket design is established with respect to maximum temperature, thermal and mechanical stress for many configurations. To satisfy hydrodynamic requirement, a4d4 (the dimension of coolant channel is 4 mm x 8 mm, and the distance between neighboring channels is 4 mm) is chosen as design point for high thermal conductivity up to 50 W/m·K

  1. Window Spacers and Edge Seals in Insulating Glass Units: A State-of-the-Art Review and Future Perspectives

    Energy Technology Data Exchange (ETDEWEB)

    SINTEF Building and Infrastructure; Norwegian University of Science and Technology (NTNU); Bergh, Sofie Van Den; Hart, Robert; Jelle, Bjrn Petter; Gustavsen, Arild

    2013-01-31

    Insulating glass (IG) units typically consist of multiple glass panes that are sealed and held together structurally along their perimeters. This report describes a study of edge seals in IG units. First, we summarize the components, requirements, and desired properties of edge construction in IG units, based on a survey of the available literature. Second, we review commercially available window edge seals and describe their properties, to provide an easily accessible reference for research and commercial purposes. Finally, based on the literature survey and review of current commercial edge seal systems, we identify research opportunities for future edge seal improvements and solutions.

  2. Carbon Nanotube Thin Films for Active Noise Cancellation, Solar Energy Harvesting, and Energy Storage in Building Windows

    Science.gov (United States)

    Hu, Shan

    This research explores the application of carbon nanotube (CNT) films for active noise cancellation, solar energy harvesting and energy storage in building windows. The CNT-based components developed herein can be integrated into a solar-powered active noise control system for a building window. First, the use of a transparent acoustic transducer as both an invisible speaker for auxiliary audio playback and for active noise cancellation is accomplished in this work. Several challenges related to active noise cancellation in the window are addressed. These include secondary path estimation and directional cancellation of noise so as to preserve auxiliary audio and internal sounds while preventing transmission of external noise into the building. Solar energy can be harvested at a low rate of power over long durations while acoustic sound cancellation requires short durations of high power. A supercapacitor based energy storage system is therefore considered for the window. Using CNTs as electrode materials, two generations of flexible, thin, and fully solid-state supercapacitors are developed that can be integrated into the window frame. Both generations consist of carbon nanotube films coated on supporting substrates as electrodes and a solid-state polymer gel layer for the electrolyte. The first generation is a single-cell parallel-plate supercapacitor with a working voltage of 3 Volts. Its energy density is competitive with commercially available supercapacitors (which use liquid electrolyte). For many applications that will require higher working voltage, the second-generation multi-cell supercapacitor is developed. A six-cell device with a working voltage as high as 12 Volts is demonstrated here. Unlike the first generation's 3D structure, the second generation has a novel planar (2D) architecture, which makes it easy to integrate multiple cells into a thin and flexible supercapacitor. The multi-cell planar supercapacitor has energy density exceeding that of

  3. Improving methane gas sensing properties of multi-walled carbonnanotubes by vanadium oxide filling

    CSIR Research Space (South Africa)

    Chimowa, George

    2017-08-01

    Full Text Available Manipulation of electrical properties and hence gas sensing properties of multi-walled carbon nanotubes (MWNTs) by filling the inner wall with vanadium oxide is presented. Using a simple capillary technique, MWNTs are filled with vanadium metal...

  4. Development of a Silicon Based Electron Beam Transmission Window for Use in a KrF Excimer Laser System

    International Nuclear Information System (INIS)

    Gentile, C.A.; Fan, H.M.; Hartfield, J.W.; Hawryluk, R.J.; Hegeler, F.; Heitzenroeder, P.J.; Jun, C.H.; Ku, L.P.; LaMarche, P.H.; Myers, M.C.; Parker, J.J.; Parsells, R.F.; Payen, M.; Raftopoulos, S.; Sethian, J.D.

    2002-01-01

    The Princeton Plasma Physics Laboratory (PPPL), in collaboration with the Naval Research Laboratory (NRL), is currently investigating various novel materials (single crystal silicon, , and ) for use as electron-beam transmission windows in a KrF excimer laser system. The primary function of the window is to isolate the active medium (excimer gas) from the excitation mechanism (field-emission diodes). Chosen window geometry must accommodate electron energy transfer greater than 80% (750 keV), while maintaining structural integrity during mechanical load (1.3 to 2.0 atm base pressure differential, approximate 0.5 atm cyclic pressure amplitude, 5 Hz repetition rate) and thermal load across the entire hibachi area (approximate 0.9 W · cm superscript ''-2''). In addition, the window must be chemically resistant to attack by fluorine free-radicals (hydrofluoric acid, secondary). In accordance with these structural, functional, and operational parameters, a 22.4 mm square silicon prototype window, coated with 500 nm thin-film silicon nitride (Si 3 N 4 ), has been fabricated. The window consists of 81 square panes with a thickness of 0.019 mm ± 0.001 mm. Stiffened (orthogonal) sections are 0.065 mm in width and 0.500 mm thick (approximate). Appended drawing (Figure 1) depicts the window configuration. Assessment of silicon (and silicon nitride) material properties and CAD modeling and analysis of the window design suggest that silicon may be a viable solution to inherent parameters and constraints

  5. Inelastic x-ray study of plasmons in oriented single and multi-walled carbon nanotubes

    International Nuclear Information System (INIS)

    Casa, D.M.; Upton, M.H.; Gog, T.; Misewich, J.; Hill, J.P.; Lowndes, D.; Eres, G.

    2006-01-01

    Carbon nanotubes (CNT) have a wide variety of interesting properties and a large number of potential aplications in electronic and optical devices. In this study we concentrate on one important aspect of their electronic stucture: the plasmon dispersions in both single- and multi-wall CNTs and their relation to those in graphite. For the first time inelastic X-ray scattering is used to study these collective electronic excitations in oriented CNT samples. The experiments were performed on the IXS instrument at beamline 9ID CMC-XOR, APS, ANL. The incident energy was defined by a Si(333) monochromator, a spherically bent Ge(733) diced analyzer at the end of a 1-m arm focused the incident radiation onto a solid-state detector. The overall resolution was ∼300 meV FWHM. The incident photons were linearly polarized perpendicular to the scattering plane. Energy loss scans were taken by varying the incident energy while keeping the exit energy fixed at 8.9805 keV. The momentum transfer was kept along the nanotubes axis. Spectra were taken at room temperature. The samples were oriented CNTs (both single- and multi-wall) grown on a Si substrate. The samples referred to as 'single-wall' were in fact a few walls at most (1-5) while the multi-walled ones had ∼12 walls. Fig. 1. shows the inelastic spectra for the single-, multi-wall, and highly oriented pyrolithic graphite (HOPG) from top to bottom. Momentum transfer was Q = 0.79 (angstrom) -1 in all cases, its direction was along the tubes for the first two samples or parallel to the sheets for graphite. The peaks at ∼10 and ∼30 eV are known as the π and σ + π plasmons respectively. Fig. 2. shows the complete dispersion curves for both plasmon modes as a function of momentum transfer for all three samples.

  6. Cross-Layer Scheme to Control Contention Window for Per-Flow in Asymmetric Multi-Hop Networks

    Science.gov (United States)

    Giang, Pham Thanh; Nakagawa, Kenji

    The IEEE 802.11 MAC standard for wireless ad hoc networks adopts Binary Exponential Back-off (BEB) mechanism to resolve bandwidth contention between stations. BEB mechanism controls the bandwidth allocation for each station by choosing a back-off value from one to CW according to the uniform random distribution, where CW is the contention window size. However, in asymmetric multi-hop networks, some stations are disadvantaged in opportunity of access to the shared channel and may suffer severe throughput degradation when the traffic load is large. Then, the network performance is degraded in terms of throughput and fairness. In this paper, we propose a new cross-layer scheme aiming to solve the per-flow unfairness problem and achieve good throughput performance in IEEE 802.11 multi-hop ad hoc networks. Our cross-layer scheme collects useful information from the physical, MAC and link layers of own station. This information is used to determine the optimal Contention Window (CW) size for per-station fairness. We also use this information to adjust CW size for each flow in the station in order to achieve per-flow fairness. Performance of our cross-layer scheme is examined on various asymmetric multi-hop network topologies by using Network Simulator (NS-2).

  7. Electrophoretic deposition (EPD) of multi-walled carbon nano tubes (MWCNT) onto indium-tin-oxide (ITO) glass substrates

    International Nuclear Information System (INIS)

    Mohd Roslie Ali; Shahrul Nizam Mohd Salleh

    2009-01-01

    Full text: Multi-Walled Carbon Nano tubes (MWCNT) were deposited onto Indium-Tin-Oxide (ITO)-coated glass substrates by introducing the use of Electrophoretic Deposition (EPD) as the method. The Multi-Walled Carbon Nano tubes (MWCNT) were dispersed ultrasonically in ethanol and sodium hydroxide (NaOH) to form stable suspension. The addition of Sodium Hydroxide in ethanol can stabilize the suspension, which was very important step before the deposition take place. Two substrates of Indium-Tin-Oxide(ITO)-coated glass placed in parallel facing each other (conductive side) into the suspension. The deposition occurs at room temperature, which the distance fixed at 1 cm between both electrodes and the voltage level applied was fixed at 400 V, respectively. The deposition time also was fixed at 30 minutes. The deposited ITO-Glass with Multi-Walled Carbon Nano tubes (MWCNT) will be characterized using Scanning Electron Microscope (SEM), Atomic Force Microscope (AFM), and Raman Microscope. The images of SEM shows that the Multi -Walled Carbon Nano tubes (MWCNT) were distributed uniformly onto the surface of ITO-Glass. The deposited ITO-Glass with Multi-Walled Carbon Nano tubes (MWCNT) could be the potential material in various practical applications such as field emission devices, fuel cells, and super capacitors. Electrophoretic deposition (EPD) technique was found to be an efficient technique in forming well distribution of Multi-Walled Carbon Nano tubes (MWCNT) onto ITO-Glass substrates, as proved in characterization methods, in which the optimum conditions will play the major role. (author)

  8. Effect of Novel Quercetin Titanium Dioxide-Decorated Multi-Walled Carbon Nanotubes Nanocomposite on Bacillus subtilis Biofilm Development

    Directory of Open Access Journals (Sweden)

    Diana S. Raie

    2018-01-01

    Full Text Available The present work was targeted to design a surface against cell seeding and adhering of bacteria, Bacillus subtilis. A multi-walled carbon nanotube/titanium dioxide nano-power was produced via simple mixing of carbon nanotube and titanium dioxide nanoparticles during the sol-gel process followed by heat treatment. Successfully, quercetin was immobilized on the nanocomposite via physical adsorption to form a quercetin/multi-walled carbon nanotube/titanium dioxide nanocomposite. The adhesion of bacteria on the coated-slides was verified after 24 h using confocal laser-scanning microscopy. Results indicated that the quercetin/multi-walled carbon nanotube/titanium dioxide nanocomposite had more negativity and higher recovery by glass surfaces than its counterpart. Moreover, coating surfaces with the quercetin-modified nanocomposite lowered both hydrophilicity and surface-attached bacteria compared to surfaces coated with the multi-walled carbon nanotubes/titanium dioxide nanocomposite.

  9. Multi-dimensional design window search system using neural networks in reactor core design

    International Nuclear Information System (INIS)

    Kugo, Teruhiko; Nakagawa, Masayuki

    2000-02-01

    In the reactor core design, many parametric survey calculations should be carried out to decide an optimal set of basic design parameter values. They consume a large amount of computation time and labor in the conventional way. To support directly design work, we investigate a procedure to search efficiently a design window, which is defined as feasible design parameter ranges satisfying design criteria and requirements, in a multi-dimensional space composed of several basic design parameters. We apply the present method to the neutronics and thermal hydraulics fields and develop the multi-dimensional design window search system using it. The principle of the present method is to construct the multilayer neural network to simulate quickly a response of an analysis code through a training process, and to reduce computation time using the neural network without parametric study using analysis codes. The system works on an engineering workstation (EWS) with efficient man-machine interface for pre- and post-processing. This report describes the principle of the present method, the structure of the system, the guidance of the usages of the system, the guideline for the efficient training of neural networks, the instructions of the input data for analysis calculation and so on. (author)

  10. Respiratory toxicity of multi-wall carbon nanotubes

    International Nuclear Information System (INIS)

    Muller, Julie; Huaux, Francois; Moreau, Nicolas; Misson, Pierre; Heilier, Jean-Francois; Delos, Monique; Arras, Mohammed; Fonseca, Antonio; Nagy, Janos B.; Lison, Dominique

    2005-01-01

    Carbon nanotubes focus the attention of many scientists because of their huge potential of industrial applications, but there is a paucity of information on the toxicological properties of this material. The aim of this experimental study was to characterize the biological reactivity of purified multi-wall carbon nanotubes in the rat lung and in vitro. Multi-wall carbon nanotubes (CNT) or ground CNT were administered intratracheally (0.5, 2 or 5 mg) to Sprague-Dawley rats and we estimated lung persistence, inflammation and fibrosis biochemically and histologically. CNT and ground CNT were still present in the lung after 60 days (80% and 40% of the lowest dose) and both induced inflammatory and fibrotic reactions. At 2 months, pulmonary lesions induced by CNT were characterized by the formation of collagen-rich granulomas protruding in the bronchial lumen, in association with alveolitis in the surrounding tissues. These lesions were caused by the accumulation of large CNT agglomerates in the airways. Ground CNT were better dispersed in the lung parenchyma and also induced inflammatory and fibrotic responses. Both CNT and ground CNT stimulated the production of TNF-α in the lung of treated animals. In vitro, ground CNT induced the overproduction of TNF-α by macrophages. These results suggest that carbon nanotubes are potentially toxic to humans and that strict industrial hygiene measures should to be taken to limit exposure during their manipulation

  11. A Multi-Walled Carbon Nanotube-based Biosensor for Monitoring Microcystin-LR in Sources of Drinking Water Supplies

    Science.gov (United States)

    A multi-walled carbon nanotube-based electrochemical biosensor is developed for monitoring microcystin-LR (MC-LR), a toxic cyanobacterial toxin, in sources of drinking water supplies. The biosensor electrodes are fabricated using dense, mm-long multi-walled CNT (MWCNT) arrays gro...

  12. Thermal performance of a room with a double glazing window using glazing available in Mexican market

    International Nuclear Information System (INIS)

    Aguilar, J.O.; Xamán, J.; Olazo-Gómez, Y.; Hernández-López, I.; Becerra, G.; Jaramillo, O.A.

    2017-01-01

    Highlights: • Thermal evaluation of a Room coupled with different types of Double Glazing Window (DGW) is analyzed. • Four cases were simulated: Case 1: DGW (clear); Case 2: DGW (absorbent), Case 3: DGW (Low-e) and Case 4: DGW (reflective). • Case 4 presents the better energy saving of all cases analyzed, ∼73% lower than Case 1. • Cases 2 and 3 have a similar thermal behavior, almost 34% less than Case 1. • The global balance costs indicate that Case 4 is the better option for energy saving in warm climate. • Case 4 allows us to save up to $20.29 USD per kW h in a year in comparison to Case 1. - Abstract: A thermal evaluation of a four configurations of double glass window (DGW) coupling to a room is presented. The DGW consists of two vertical semitransparent walls separated by a 12 mm air gap. The effect of varying the ambient temperature and the incident solar radiation in the warm climate conditions in México is analyzed. Numerical simulations were conducted for four configurations; Case 1: clear glass + air gap + clear glass (Reference); Case 2: clear glass + air gap + absorbent glass; Case 3: clear glass + air gap + Low-e glass; and Case 4: clear glass + air gap + reflective glass. Optical transmittance and specular reflectance were measured individually and in one sample piece for each case. The results showed that Case 4 reduces the heat flux to the indoors by up to 73%, with respect to Case 1. Moreover, Cases 2 and 3 had a similar behavior, obtaining a reduction of indoor heat flow close to 33.5% with respect to Case 1. Case 4 is the best option for energy savings in a warm climate, where it is possible to save up to $20.29 USD per kW h per year, in comparison to Case 1. In addition, the payback period for Case 4 is 3.7 years. Therefore, the use of reflective double pane window is highly recommended in Mexican warm climates.

  13. Application of multi-walled carbon nanotubes to enhance anodic ...

    African Journals Online (AJOL)

    The effect of multi-walled carbon nanotube (MWCNT) modification of anodes and the optimisation of relevant parameters thereof for application in an Enterobacter cloacae microbial fuel cell were examined. The H – type microbial fuel cells were used for the fundamental studies, with a carbon sheet as a control anode and ...

  14. THE EFFECT OF THE WINDOW-TO-WALL RATIO ON COOLING ENERGY USAGE AND COMFORT TEMPERATURE

    Directory of Open Access Journals (Sweden)

    Aris Budhiyanto

    2017-12-01

    Full Text Available This study presents an investigation of the effect of building envelope, especially glass facade buildings on cooling energy usage and thermal comfort. An office building was modeled with various window-to-wall ratio (WWR using panasap glass with SC=0.58 in order to analyze the effect of the WWR addition on cooling energy usage and comfort temperature. The result suggested that the average increase of the cooling energy usage is about 5.67% per 10% WWR addition, and of the operative temperature ranges from 0.350C to 0.560C per 10% WWR addition. Moreover, the building with above 20% WWR doesn’t provide comfort temperature.

  15. Effects of opening in shear walls of 30- storey building

    Directory of Open Access Journals (Sweden)

    Ruchi Sharma

    2015-03-01

    Full Text Available Tall towers and multi-storey buildings have fascinated mankind from the beginning of civilization, their construction being initially for defense and subsequently for ecclesiastical purposes. These tall buildings because of its height, is affected by lateral forces due to wind or earthquake actions tends to snap the building in shear and push it over in bending. In general, the rigidity (i.e. Resistance to lateral deflection and stability (i.e. Resistance to overturning moments requirement become more important. Shear walls (Structural walls contribute significant lateral stiffness, strength, and overall ductility and energy dissipation capacity. In many structural walls a regular pattern of openings has to be provided due to various functional requirements such as to accommodate doors, windows and service ducts. Such type of openings reduces the stiffness of the shear wall to some extent depending on the shape and size of the opening. In the present parametric study, efforts are made to investigate and critically assess the effects of various size of openings in shear walls on the responses and behaviors of multi-storey buildings. The 30 storey Prototype buildings with different types of openings in shear wall with and without incorporating the volume of shear wall reduced in the boundary elements are analyzed using software E-TABS using Response spectrum method (1893(Part-1-2002 and Time history method.

  16. Water-Dispersible Multi-Walled Carbon Nanotubes and Novel Hybrid Nanostructures

    NARCIS (Netherlands)

    Pham, Tuan Anh; Son, Se Mo; Jeong, Yeon Tae

    2010-01-01

    Water-dispersible multi-walled carbon nanotubes (MWNTs) were successfully prepared by the chemical grafting of acylated MWNTs with adenosine. The MWNTs were first purified and oxidized in order to obtain carboxylic acid funcionalized MWNTs, which was further acylated with thionyl chloride to give

  17. 49 CFR Figure 2b to Subpart B of... - Example of an Intermediate Level Seating Area of a Multi-Level Car Complying With Window Location...

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Example of an Intermediate Level Seating Area of a Multi-Level Car Complying With Window Location Requirements-§§ 238.113 and 238.114 2B Figure 2B to... Intermediate Level Seating Area of a Multi-Level Car Complying With Window Location Requirements—§§ 238.113 and...

  18. 49 CFR Figure 2a to Subpart B of... - Example of an Intermediate Level Seating Area of a Multi-Level Car Complying With Window Location...

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Example of an Intermediate Level Seating Area of a Multi-Level Car Complying With Window Location Requirements-§§ 238.113 and 238.114 2A Figure 2A to... Intermediate Level Seating Area of a Multi-Level Car Complying With Window Location Requirements—§§ 238.113 and...

  19. Supramolecular modification of multi-walled carbon nanotubes with β-cyclodextrin for better dispersibility

    International Nuclear Information System (INIS)

    He, Yi; Xu, Zhonghao; Yang, Qiangbin; Wu, Feng; Liang, Lv

    2015-01-01

    A novel hybrid material based on multi-walled carbon nanotubes was synthesized using organic synthesis, and the structures of multi-walled carbon nanotube derivatives were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, 1 H NMR spectroscopy, transmission electron microscopy, and scanning electron microscope. The analytical results indicated that β-cyclodextrin (β-CD) was anchored to the surface of Multi-walled carbon nanotubes (MWCNTs, OD: 10–20 nm, length: 10–30 μm) and dispersion experiments exhibited that the introduction of β-CD onto the MWCNTs would dramatically enhance the dispersion of MWCNTs in both ethanol and water media; the suspensions were found to be very stable for 2 months, and the results of this technique confirmed the experimental results. This novel technique would provide a new, simple, and facile route to prepare the modified nanomaterials based on silane-coupling agent and β-CD, and the obtained modified nanomaterials have great potential practical significance and theoretical value to develop the novel organic–inorganic hybrid material, which was very useful for water treatment and biological medicine

  20. A scale-entropy diffusion equation to describe the multi-scale features of turbulent flames near a wall

    Science.gov (United States)

    Queiros-Conde, D.; Foucher, F.; Mounaïm-Rousselle, C.; Kassem, H.; Feidt, M.

    2008-12-01

    Multi-scale features of turbulent flames near a wall display two kinds of scale-dependent fractal features. In scale-space, an unique fractal dimension cannot be defined and the fractal dimension of the front is scale-dependent. Moreover, when the front approaches the wall, this dependency changes: fractal dimension also depends on the wall-distance. Our aim here is to propose a general geometrical framework that provides the possibility to integrate these two cases, in order to describe the multi-scale structure of turbulent flames interacting with a wall. Based on the scale-entropy quantity, which is simply linked to the roughness of the front, we thus introduce a general scale-entropy diffusion equation. We define the notion of “scale-evolutivity” which characterises the deviation of a multi-scale system from the pure fractal behaviour. The specific case of a constant “scale-evolutivity” over the scale-range is studied. In this case, called “parabolic scaling”, the fractal dimension is a linear function of the logarithm of scale. The case of a constant scale-evolutivity in the wall-distance space implies that the fractal dimension depends linearly on the logarithm of the wall-distance. We then verified experimentally, that parabolic scaling represents a good approximation of the real multi-scale features of turbulent flames near a wall.

  1. Multi-slice spiral CT coronary angiography: influence of heart rate and reconstruction window on image quality

    International Nuclear Information System (INIS)

    Mao Dingbiao; Hua Yanqing; Wang Mingpeng; Zhang Guozhen; Wu Weilan; Hu Fei; Ge Xiaojun; Ding Qiyong

    2004-01-01

    Objective: To evaluate the influence of heart rate and reconstruction window on image quality of multi-slice spiral CT coronary angiography. Methods: Retrospectively ECG-gated MSCT coronary angiography were performed in 80 healthy cases. Results: Four coronary (RCA, LM, LAD, LCX) segments were analyzed in each patient with regard to image quality. 82.1% (46/56) of the coronary segments were sufficient for analysis in patients with heart rate ≤60 bpm, 63.4% (104/164) with 61-70 bpm, 41.2%(28/68) with 71-80 bpm, and 31.2%(10/32) with>80 bpm, respectively. The left anterior descending artery, left circumflex artery, and the right coronary artery were best visualized when the reconstruction window was 60%-70%, 50%-60%, and 50%-70%, respectively. Conclusion: Image quality of MSCT coronary angiography is highly dependent on heart rate and reconstruction window

  2. Efecto del uso de diferentes aditivos de panificación en la calidad de panes elaborados con harinas compuestas a base de harina de trigo y germen desgrasado de maíz

    Directory of Open Access Journals (Sweden)

    Marisela Granito

    1997-08-01

    Full Text Available Dado el alto consumo de productos alimenticios a base de trigo (HT importado y la producción industrial de subproductos del procesamiento del maíz (HGDM, ricos en fibra dietética, proteínas y minerales, en Venezuela se ha estudado la factibilidad técnica de sustituir parcialmente HT por HGDM en la elaboración de productos horneados como galletas y panes. Por otra parte, considerando las restricciones existentes en el uso del bromato de potasio (BP como aditivo de panificación y que el ácido ascórbico (AA ha sido probado exitosamente como aditivo en panes a base de HT, en este estudio se utilizaron los aditivos (BP, (AA, gluten y mezclas de ellos, en la elaboración de panes donde la HT fue sustituida por HGDM a niveles de 10% y 15%. Se encontro que las mezclas de aditivos que originaron los menores pesos específicos fueron las que contenían gluten , seguidas por 75 ppm AA y 25 ppm BP. Se observo el efecto sinergístico de estos dos aditivos, tanto en los panes control como en los que contenían HGDM. Se puede concluir que la calidad panificable y el proceso de envejecimiento en los panes donde se sustituye la HT por HGDM, a niveles de 10%, sigue patrones similares al de los panes de 100% HT, por lo que se podría considerar viable dicha sustitución. A niveles de 15% de sustitución, la presencia de fibra origina algunos cambios en el patrón de comportamiento, por lo que se sugiere el uso de hemicelulasas en las mezclas.

  3. Detailed profiling of CNTs arrays along the growth window in a floating catalyst reactor

    International Nuclear Information System (INIS)

    Maghrebi, Morteza; Khodadadi, Abbas Ali; Mortazavi, Yadollah; Mhaisalkar, Subodh

    2009-01-01

    We report a detailed longitudinal and depth profiles of multi-wall carbon nanotubes (CNTs) arrays synthesized using xylene and ferrocene in a floating catalyst reactor. Point to point analyses of the CNTs grown in a 'growth window' with CNTs arrays longer than 0.5 mm were performed using optical microscopy, Raman spectroscopy, FESEM, high-resolution TGA/DTA, and TEM techniques. The heights of the CNTs arrays show a maximum at a mid point of the growth window, while a reverse trend of minimum is observed for iron-to-CNTs atomic ratios. The ratio of amorphous carbon to CNTs sharply increases along the growth window and from the bottom to top of CNTs arrays. The CNTs diameter also increases along the growth window, due to deposition of the amorphous carbon, which can be almost removed by temperature programmed oxidation up to around 500 deg. C. A base growth mechanism, the variations of catalyst content, residence time and temperature profile along the growth window, the adsorption and decomposition of polycyclic aromatic hydrocarbons to amorphous carbon, and a limited diffusion of hydrocarbon species through the arrays covered by excessive amorphous carbon may explain the results.

  4. Development of windows based on highly insulating aerogel glazings

    DEFF Research Database (Denmark)

    Jensen, Karsten Ingerslev; Schultz, Jørgen Munthe; Kristiansen, Finn Harken

    2004-01-01

    of buildings, the window area is the weakest part with respect to the heat loss, but at the same time, it also provides e.g. solar energy gain. Glazing prototypes have been made of aerogel tiles of about 55 cm sq. (elaborated within the projects). Those tiles are quickly evacuated and easily sealed between two...... glass panes and a specific rim seal. A heat treatment phase (after the supercritical CO2 drying) of the aerogel is currently being developed in order to improve its optical quality. This step increases the solar transmittance about 6 percent points. For glazing prototypes with an aerogel thickness...... of approx. 15 mm, a centre heat loss coefficient of below 0.7 W/m² K and a solar transmittance of 76% have been obtained. The research is funded in part by the European Commission within the frameworks of the Non-Nuclear Energy Programme – JOULE III and the Energy, Environment and Sustainable Development...

  5. SU-E-T-478: Sliding Window Multi-Criteria IMRT Optimization

    International Nuclear Information System (INIS)

    Craft, D; Papp, D; Unkelbach, J; Bokrantz, R

    2014-01-01

    Purpose: To demonstrate a method for what-you-see-is-what-you-get multi-criteria Pareto surface navigation for step and shoot IMRT treatment planning. Methods: We show mathematically how multiple sliding window treatment plans can be averaged to yield a single plan whose dose distribution is the dosimetric average of the averaged plans. This is incorporated into the Pareto surface navigation based approach to treatment planning in such a way that as the user navigates the surface, the plans he/she is viewing are ready to be delivered (i.e. there is no extra ‘segment the plans’ step that often leads to unacceptable plan degradation in step and shoot Pareto surface navigation). We also describe how the technique can be applied to VMAT. Briefly, sliding window VMAT plans are created such that MLC leaves paint out fluence maps every 15 degrees or so. These fluence map leaf trajectories are averaged in the same way the static beam IMRT ones are. Results: We show mathematically that fluence maps are exactly averaged using our leaf sweep averaging algorithm. Leaf transmission and output factor corrections effects, which are ignored in this work, can lead to small errors in terms of the dose distributions not being exactly averaged even though the fluence maps are. However, our demonstrations show that the dose distributions are almost exactly averaged as well. We demonstrate the technique both for IMRT and VMAT. Conclusions: By turning to sliding window delivery, we show that the problem of losing plan fidelity during the conversion of an idealized fluence map plan into a deliverable plan is remedied. This will allow for multicriteria optimization that avoids the pitfall that the planning has to be redone after the conversion into MLC segments due to plan quality decline. David Craft partially funded by RaySearch Laboratories

  6. SU-E-T-478: Sliding Window Multi-Criteria IMRT Optimization

    Energy Technology Data Exchange (ETDEWEB)

    Craft, D; Papp, D; Unkelbach, J [Massachusetts General Hospital, Boston, MA (United States); Bokrantz, R [RaySearch Laboratories, Stockholm (Sweden)

    2014-06-01

    Purpose: To demonstrate a method for what-you-see-is-what-you-get multi-criteria Pareto surface navigation for step and shoot IMRT treatment planning. Methods: We show mathematically how multiple sliding window treatment plans can be averaged to yield a single plan whose dose distribution is the dosimetric average of the averaged plans. This is incorporated into the Pareto surface navigation based approach to treatment planning in such a way that as the user navigates the surface, the plans he/she is viewing are ready to be delivered (i.e. there is no extra ‘segment the plans’ step that often leads to unacceptable plan degradation in step and shoot Pareto surface navigation). We also describe how the technique can be applied to VMAT. Briefly, sliding window VMAT plans are created such that MLC leaves paint out fluence maps every 15 degrees or so. These fluence map leaf trajectories are averaged in the same way the static beam IMRT ones are. Results: We show mathematically that fluence maps are exactly averaged using our leaf sweep averaging algorithm. Leaf transmission and output factor corrections effects, which are ignored in this work, can lead to small errors in terms of the dose distributions not being exactly averaged even though the fluence maps are. However, our demonstrations show that the dose distributions are almost exactly averaged as well. We demonstrate the technique both for IMRT and VMAT. Conclusions: By turning to sliding window delivery, we show that the problem of losing plan fidelity during the conversion of an idealized fluence map plan into a deliverable plan is remedied. This will allow for multicriteria optimization that avoids the pitfall that the planning has to be redone after the conversion into MLC segments due to plan quality decline. David Craft partially funded by RaySearch Laboratories.

  7. Phytotoxicity of multi-walled carbon nanotubes on red spinach (Amaranthus tricolor L) and the role of ascorbic acid as an antioxidant

    International Nuclear Information System (INIS)

    Begum, Parvin; Fugetsu, Bunshi

    2012-01-01

    Highlights: ► MWNTs are selected for study of the systemic toxicity and the potential influence on red spinach. ► Microscopic observation revealed some adverse effects on root and leaf. ► Cell damage were detected on 15 days after the exposure to MWNTs. ► ROS increase ceased once ascorbic acid was added into media. ► Oxidative stress seems to be the key element responsible for causing the toxicity. - Abstract: Carbon nanotubes (CNTs) are a novel nanomaterial with wide potential applications; however the adverse effects of CNTs following environmental exposure have recently received significant attention. Herein, we explore the systemic toxicity and potential influence of 0–1000 mg L −1 the multi-walled CNTs on red spinach. The multi-walled CNTs exposed plants exhibited growth inhibition and cell death after 15 days of hydroponic culture. The multi-walled CNTs had adverse effects on root and leaf morphology, as observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Raman spectroscopy detected the multi-walled CNTs in leaves. Biomarkers of nanoparticle toxicity, reactive oxygen species (ROS), and cell damage in the red spinach were greatly increased 15 days post-exposure to the multi-walled CNTs. These effects were reversed when the multi-walled CNTs were supplemented with ascorbic acid (AsA), suggesting a role of ROS in the multl-walled CNT-induced toxicity and that the primary mechanism of the multi-walled CNTs’ toxicity is oxidative stress.

  8. LiveWall Operational Evaluation: Seattle Law Enforcement Pilot

    Energy Technology Data Exchange (ETDEWEB)

    Barr, Jonathan L.; Burtner, Edwin R.; Stein, Steven L.

    2013-10-01

    The LiveWall concept envisioned as an outgrowth of the Precision Information Environment (PIE) project allows communications between separate groups using interactive video, audio, and a shared desktop environment; this allows everyone to participate and collaborate in real time, regardless of location. The LiveWall concept provides a virtual window to other locations, where all parties can interact and collaboratively work with each other. This functionality is intended to improve multi-site coordination amongst emergency operations centers (EOC), field operations sites and across organizations and jurisdictions to accommodate communications during routine and emergency events. For the initial LiveWall operational evaluation PNNL partnered with the Seattle Police Department (SPD). This partnership allowed for the creation of an excellent LiveWall test bed specific to law enforcement. This partnership made it possible to test the LiveWall concept with scenarios involving the many facets of the law enforcement work done by SPD. PNNL and SPD agreed that integrating the systems into operations for a real event would be the best test of the technology and give SPD staff greater visibility into the functionality and benefits offered by the LiveWall concept.

  9. Phytotoxicity of multi-walled carbon nanotubes on red spinach (Amaranthus tricolor L) and the role of ascorbic acid as an antioxidant

    Energy Technology Data Exchange (ETDEWEB)

    Begum, Parvin [Laboratory of Environmental Medical Chemistry, Graduate School of Environmental Science, Hokkaido University, Sapporo 060-0810 (Japan); Fugetsu, Bunshi, E-mail: hu@ees.hokudai.ac.jp [Laboratory of Environmental Medical Chemistry, Graduate School of Environmental Science, Hokkaido University, Sapporo 060-0810 (Japan)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer MWNTs are selected for study of the systemic toxicity and the potential influence on red spinach. Black-Right-Pointing-Pointer Microscopic observation revealed some adverse effects on root and leaf. Black-Right-Pointing-Pointer Cell damage were detected on 15 days after the exposure to MWNTs. Black-Right-Pointing-Pointer ROS increase ceased once ascorbic acid was added into media. Black-Right-Pointing-Pointer Oxidative stress seems to be the key element responsible for causing the toxicity. - Abstract: Carbon nanotubes (CNTs) are a novel nanomaterial with wide potential applications; however the adverse effects of CNTs following environmental exposure have recently received significant attention. Herein, we explore the systemic toxicity and potential influence of 0-1000 mg L{sup -1} the multi-walled CNTs on red spinach. The multi-walled CNTs exposed plants exhibited growth inhibition and cell death after 15 days of hydroponic culture. The multi-walled CNTs had adverse effects on root and leaf morphology, as observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Raman spectroscopy detected the multi-walled CNTs in leaves. Biomarkers of nanoparticle toxicity, reactive oxygen species (ROS), and cell damage in the red spinach were greatly increased 15 days post-exposure to the multi-walled CNTs. These effects were reversed when the multi-walled CNTs were supplemented with ascorbic acid (AsA), suggesting a role of ROS in the multl-walled CNT-induced toxicity and that the primary mechanism of the multi-walled CNTs' toxicity is oxidative stress.

  10. A methodology to enlarge narrow stability windows

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Ewerton M.P.; Pastor, Jorge A.S.C.; Fontoura, Sergio A.B. [Pontificia Univ. Catolica do Rio de Janeiro (PUC-Rio), RJ (Brazil). Dept. de Engenharia Civil. Grupo de Tecnologia e Engenharia de Petroleo

    2004-07-01

    The stability window in a wellbore design is defined by the difference between fracture pressure and collapse pressure. Deep water environments typically present narrow stability windows, because rocks have low strength due to under-compaction process. Often also, horizontal wells are drilled to obtain a better development of reservoirs placed in thin layers of sandstone. In this scenario, several challenges are faced when drilling in deep water. The traditional approach for predicting instabilities is to determine collapses and fractures at borehole wall. However, the initiation of rupture does not indicate that the borehole fails to perform its function as a wellbore. Thus, a methodology in which the stability window may be enlarged is desirable. This paper presents one practical analytical methodology that consists in allowing wellbore pressures smaller than the conventional collapse pressure, i.e., based upon failure on the borehole wall. This means that a collapse region (shear failure) will be developed around the borehole wall. This collapse region is pre-defined and to estimate its size is used a failure criterion. The aforementioned methodology is implemented in a user-friendly software, which can perform analyses of stress, pore pressure, formation failure, mud weight and mud salinity design for drilling in shale formations. Simulations of a wellbore drilling in a narrow stability window environment are performed to demonstrate the improvements of using the methodology. (author)

  11. MULTI-LEVEL SAMPLING APPROACH FOR CONTINOUS LOSS DETECTION USING ITERATIVE WINDOW AND STATISTICAL MODEL

    OpenAIRE

    Mohd Fo'ad Rohani; Mohd Aizaini Maarof; Ali Selamat; Houssain Kettani

    2010-01-01

    This paper proposes a Multi-Level Sampling (MLS) approach for continuous Loss of Self-Similarity (LoSS) detection using iterative window. The method defines LoSS based on Second Order Self-Similarity (SOSS) statistical model. The Optimization Method (OM) is used to estimate self-similarity parameter since it is fast and more accurate in comparison with other estimation methods known in the literature. Probability of LoSS detection is introduced to measure continuous LoSS detection performance...

  12. Nanotechnology And Examination Of Multi Walled Carbon Nanotubes

    OpenAIRE

    Kutucu, Burcu

    2010-01-01

    The main subject of this study is the definition of nanotechnology, benefits of nanotechnology, nanotechnology applications in Turkey and world and the history of nanotechnology. Also single and multi walled carbon nanotubes and Van der Waals bands are examined in this study. At first a fixed end frame loaded with a load P is studied and governing equations solved in MATHEMATICA. Secontly the same procedure is repeated for a fixed and frame loaded with moment M is studied and governing equati...

  13. Polyaniline–multi-wall-carbon nanotube nanocomposites as a dopamine sensor

    Directory of Open Access Journals (Sweden)

    REZA EMAMALI SABZI

    2010-04-01

    Full Text Available A composite of polyaniline with multi-wall-carbon nanotubes (PANi/ /MWCNTs was synthesized by an in situ chemical oxidative polymerization method. The PANi nanoparticles were synthesized chemically using aniline as the monomer and ammonium peroxydisulfate as the oxidant. The nanocomposites were prepared as a carbon paste using functionalized MWCNTs and PANi nanoparticles. The PANi–MWCNTs were characterized physically using scanning electron microscopy (SEM and the electrochemical behavior of the composites in acidic solution (HCl was investigated using cyclic voltammetry. The PANi/MWCNT composite electrode was used for studying dopamine (DA as an electroactive material. The cyclic voltammetric results indicated that multi-wall carbon nanotubes (MWCNTs significantly enhanced the electrocatalytic activity in favor of the oxidation of DA. The kinetics of the catalytic reaction was investigated using the chronoamperometry technique whereby the average va¬lue of the diffusion coefficient (D and the catalytic rate constant (k for DA were determined to be (7.98±0.8×10-7 cm2 s-1 and (8.33±0.072×104 dm3 mol-1 s-1, respectively.

  14. Binding energy and mechanical stability of single- and multi-walled carbon nanotube serpentines

    International Nuclear Information System (INIS)

    Zhao, Junhua; Lu, Lixin; Rabczuk, Timon

    2014-01-01

    Recently, Geblinger et al. [Nat. Nanotechnol. 3, 195 (2008)] and Machado et al. [Phys. Rev. Lett. 110, 105502 (2013)] reported the experimental and molecular dynamics realization of S-like shaped single-walled carbon nanotubes (CNTs), the so-called CNT serpentines. We reported here results from continuum modeling of the binding energy γ between different single- and multi-walled CNT serpentines and substrates as well as the mechanical stability of the CNT serpentine formation. The critical length for the mechanical stability and adhesion of different CNT serpentines are determined in dependence of E i I i , d, and γ, where E i I i and d are the CNT bending stiffness and distance of the CNT translation period. Our continuum model is validated by comparing its solution to full-atom molecular dynamics calculations. The derived analytical solutions are of great importance for understanding the interaction mechanism between different single- and multi-walled CNT serpentines and substrates

  15. Multi-wall carbon nanotubes with nitrogen-containing carbon coating

    Czech Academy of Sciences Publication Activity Database

    Tomšík, Elena; Morávková, Zuzana; Stejskal, Jaroslav; Trchová, Miroslava; Šálek, Petr; Kovářová, Jana; Zemek, Josef; Cieslar, M.; Prokeš, J.

    2013-01-01

    Roč. 67, č. 8 (2013), s. 1054-1065 ISSN 0366-6352 R&D Projects: GA ČR GPP108/11/P763; GA ČR GAP205/12/0911; GA ČR GA202/09/0428 Institutional support: RVO:61389013 ; RVO:68378271 Keywords : polyaniline coating * carbon ization * multi-wall carbon nanotubes Subject RIV: CD - Macromolecular Chemistry; BM - Solid Matter Physics ; Magnetism (FZU-D) Impact factor: 1.193, year: 2013

  16. Live histograms in moving windows

    International Nuclear Information System (INIS)

    Zhil'tsov, V.E.

    1989-01-01

    Application of computer graphics for specific hardware testing is discussed. The hardware is position sensitive detector (multiwire proportional chamber) which is used in high energy physics experiments, and real-out electronics for it. Testing program is described (XPERT), which utilises multi-window user interface. Data are represented as histograms in windows. The windows on the screen may be moved, reordered, their sizes may be changed. Histograms may be put to any window, and hardcopy may be made. Some program internals are discussed. The computer environment is quite simple: MS-DOS IBM PC/XT, 256 KB RAM, CGA, 5.25'' FD, Epson MX. 4 refs.; 7 figs

  17. Multi-bunch effect of resistive wall in the Beam Delivery System of the Compact Linear Collider

    CERN Document Server

    Mutzner, R; Rumolo, G; Tomas, R; Pieloni, T

    2010-01-01

    Wake fields in the CLIC Beam Delivery System (BDS) can cause severe single or multi-bunch effects leading to luminosity loss. The main contributors in the BDS are geometric and resistive wall wake fields of the collimators and resistive wall wakes of the beam pipe. The present work focuses only on the multi-bunch effects from resistive wall. Using particle tracking with wake fields through the BDS, we have established the aperture radius, above which the effect of the wake fields becomes negligible. Our simulations were later extended to include a realistic aperture model along the BDS as well as the collimators. The two cases of 3 TeV and 500 GeV have been examined.

  18. Exam 70-411 administering Windows Server 2012

    CERN Document Server

    Course, Microsoft Official Academic

    2014-01-01

    Microsoft Windows Server is a multi-purpose server designed to increase reliability and flexibility of  a network infrastructure. Windows Server is the paramount tool used by enterprises in their datacenter and desktop strategy. The most recent versions of Windows Server also provide both server and client virtualization. Its ubiquity in the enterprise results in the need for networking professionals who know how to plan, design, implement, operate, and troubleshoot networks relying on Windows Server. Microsoft Learning is preparing the next round of its Windows Server Certification program

  19. Prediction of the microsurgical window for skull-base tumors by advanced three-dimensional multi-fusion volumetric imaging

    International Nuclear Information System (INIS)

    Oishi, Makoto; Fukuda, Masafumi; Saito, Akihiko; Hiraishi, Tetsuya; Fujii, Yukihiko; Ishida, Go

    2011-01-01

    The surgery of skull base tumors (SBTs) is difficult due to the complex and narrow surgical window that is restricted by the cranium and important structures. The utility of three-dimensional multi-fusion volumetric imaging (3-D MFVI) for visualizing the predicted window for SBTs was evaluated. Presurgical simulation using 3-D MFVI was performed in 32 patients with SBTs. Imaging data were collected from computed tomography, magnetic resonance imaging, and digital subtraction angiography. Skull data was processed to imitate actual bone resection and integrated with various structures extracted from appropriate imaging modalities by image-analyzing software. The simulated views were compared with the views obtained during surgery. All craniotomies and bone resections except opening of the acoustic canal in 2 patients were performed as simulated. The simulated window allowed observation of the expected microsurgical anatomies including tumors, vasculatures, and cranial nerves, through the predicted operative window. We could not achieve the planned tumor removal in only 3 patients. 3-D MFVI afforded high quality images of the relevant microsurgical anatomies during the surgery of SBTs. The intraoperative deja-vu effect of the simulation increased the confidence of the surgeon in the planned surgical procedures. (author)

  20. Extraction of ochratoxin A in red wine with dopamine-coated magnetic multi-walled carbon nanotubes.

    Science.gov (United States)

    Wan, Hong; Zhang, Bo; Bai, Xiao-Lin; Zhao, Yan; Xiao, Meng-Wei; Liao, Xun

    2017-10-01

    A new, rapid, green, and cost-effective magnetic solid-phase extraction of ochratoxin A from red wine samples was developed using polydopamine-coated magnetic multi-walled carbon nanotubes as the absorbent. The polydopamine-coated magnetic multi-walled carbon nanotubes were fabricated with magnetic multi-walled carbon nanotubes and dopamine by an in situ oxidative self-polymerization approach. Transmission electron microscopy, dynamic light scattering, X-ray photoelectron spectroscopy and vibrating sample magnetometry were used to characterize the absorbents. Ochratoxin A was quantified with high-performance liquid chromatography coupled with fluorescence detection, with excitation and emission wavelengths of 338 and 455 nm, respectively. The conditions affecting the magnetic solid-phase extraction procedure, such as pH, extraction solution, extraction time, absorbent amount, desorption solution and desorption time were investigated to obtain the optimal extraction conditions. Under the optimized conditions, the extraction recovery was 91.8-104.5% for ochratoxin A. A linear calibration curve was obtained in the range of 0.1-2.0 ng/mL. The limit of detection was 0.07 ng/mL, and the limit of quantitation was 0.21 ng/mL. The recoveries of ochratoxin A for spiked red wine sample ranged from 95.65 to 100.65% with relative standard deviation less than 8%. The polydopamine-coated magnetic multi-walled carbon nanotubes showed a high affinity toward ochratoxin A, allowing selective extraction and quantification of ochratoxin A from complex sample matrixes. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Application of neural network to multi-dimensional design window search

    International Nuclear Information System (INIS)

    Kugo, T.; Nakagawa, M.

    1996-01-01

    In the reactor core design, many parametric survey calculations should be carried out to decide an optimal set of basic design parameter values. They consume a large amount of computation time and labor in the conventional way. To support directly such a work, we investigate a procedure to search efficiently a design window, which is defined as feasible design parameter ranges satisfying design criteria and requirements, in a multi-dimensional space composed of several basic design parameters. A principle of the present method is to construct the multilayer neural network to simulate quickly a response of an analysis code through a training process, and to reduce computation time using the neural network as a substitute of an analysis code. We apply the present method to a fuel pin design of high conversion light water reactors for the neutronics and thermal hydraulics fields to demonstrate performances of the method. (author)

  2. Photonic crystal-adaptive optical devices

    DEFF Research Database (Denmark)

    Buss, Thomas

    This Ph.D. thesis presents methods for enhancing the optical functionality of transparent glass panes by introduction of invisible nanoscale surface structures, such as gratings and planar photonic cyrstals. In this way the primary functionality of the glass - transparancy - may be enhanced...... been designed, fabricated and analyzed. First a solar harvesting method, based on nanoscale gratings which are imprinted in a thin-film which is deposited on the window pane is discussed. Free-space light which is incident onto a window is coupled to guided modes in the thin-film or the substrate...

  3. Application of Multi-Layered Polyurethane Foams for Flat-Walled Anechoic Linings

    DEFF Research Database (Denmark)

    Xu, J. F.; Buchholz, Jörg; Fricke, Fergus R.

    2006-01-01

    of the application of multi-layered polyurethane foams as the flat-walled anechoic lining. The investigation includes aspects such as the efficacy of a single layer of material, the minimum number of layers of linings to achieve the minimum overall thickness for low (100Hz), mid (250Hz) and high (500Hz) cut...

  4. Electronic structure of multi-walled carbon fullerenes

    International Nuclear Information System (INIS)

    Doore, Keith; Cook, Matthew; Clausen, Eric; Lukashev, Pavel V; Kidd, Tim E; Stollenwerk, Andrew J

    2017-01-01

    Despite an enormous amount of research on carbon based nanostructures, relatively little is known about the electronic structure of multi-walled carbon fullerenes, also known as carbon onions. In part, this is due to the very high computational expense involved in estimating electronic structure of large molecules. At the same time, experimentally, the exact crystal structure of the carbon onion is usually unknown, and therefore one relies on qualitative arguments only. In this work we present the results of a computational study on a series of multi-walled fullerenes and compare their electronic structures to experimental data. Experimentally, the carbon onions were fabricated using ultrasonic agitation of isopropanol alcohol and deposited onto the surface of highly ordered pyrolytic graphite using a drop cast method. Scanning tunneling microscopy images indicate that the carbon onions produced using this technique are ellipsoidal with dimensions on the order of 10 nm. The majority of differential tunneling spectra acquired on individual carbon onions are similar to that of graphite with the addition of molecular-like peaks, indicating that these particles span the transition between molecules and bulk crystals. A smaller, yet sizable number exhibited a semiconducting gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) levels. These results are compared with the electronic structure of different carbon onion configurations calculated using first-principles. Similar to the experimental results, the majority of these configurations are metallic with a minority behaving as semiconductors. Analysis of the configurations investigated here reveals that each carbon onion exhibiting an energy band gap consisted only of non-metallic fullerene layers, indicating that the interlayer interaction is not significant enough to affect the total density of states in these structures. (paper)

  5. The effect of calcination on multi-walled carbon nanotubes produced by dc-arc discharge.

    Science.gov (United States)

    Pillai, Sreejarani K; Augustyn, Willem G; Rossouw, Margaretha H; McCrindle, Robert I

    2008-07-01

    Multi-walled carbon nanotubes were synthesized by dc-arc discharge in helium atmosphere and the effect of calcination at different temperatures ranging from 300-600 degrees C was studied in detail. The degree of degradation to the structural integrity of the multi-walled carbon nanotubes during the thermal process was studied by Raman spectroscopy, Scanning electron microscopy and High resolution transmission electron microscopy. The thermal behaviour of the as prepared and calcined samples was investigated by thermogravimetric analysis. Calcination in air at 400 degrees C for 2 hours was found to be an efficient and simple method to eliminate carbonaceous impurities from the nanotube bundles with minimal damage to the tube walls and length. The impurities were oxidized at a faster rate when compared to the nanotubes and gave good yield of about 50%. The nanotubes were observed to be damaged at temperature higher than 450 degrees C. The results show that this method is less destructive when compared liquid phase oxidation with 5 M HNO3.

  6. Multi-Bunch effect of resistive wall in the beam delivery system of the Compact Linear Collider

    CERN Document Server

    Mutzner, Raphael; Pieloni, Tatiana; Rivkin, Leonid

    2010-01-01

    Wake fields in the CLIC Beam Delivery System (BDS) can cause severe single or multi-bunch effects leading to luminosity loss. The main contributors in the BDS are geometric and resistive wall wake fields of the collimators and resistive wall wakes of the beam pipe. The present master thesis focuses only on the multi-bunch effects from resistive wall. Using particle tracking with wake fields through the BDS, we have established the aperture radius, above which the effect of the wake fields becomes negligible. Simulations were later extended to include a realistic aperture model along the BDS as well as the collimators. We examine the two cases of 3 TeV and 500 GeV in this work, for stainless steel and copper pipes.

  7. Hybrid fibers made of molybdenum disulfide, reduced graphene oxide, and multi-walled carbon nanotubes for solid-state, flexible, asymmetric supercapacitors.

    Science.gov (United States)

    Sun, Gengzhi; Zhang, Xiao; Lin, Rongzhou; Yang, Jian; Zhang, Hua; Chen, Peng

    2015-04-07

    One of challenges existing in fiber-based supercapacitors is how to achieve high energy density without compromising their rate stability. Owing to their unique physical, electronic, and electrochemical properties, two-dimensional (2D) nanomaterials, e.g., molybdenum disulfide (MoS2 ) and graphene, have attracted increasing research interest and been utilized as electrode materials in energy-related applications. Herein, by incorporating MoS2 and reduced graphene oxide (rGO) nanosheets into a well-aligned multi-walled carbon nanotube (MWCNT) sheet followed by twisting, MoS2 -rGO/MWCNT and rGO/MWCNT fibers are fabricated, which can be used as the anode and cathode, respectively, for solid-state, flexible, asymmetric supercapacitors. This fiber-based asymmetric supercapacitor can operate in a wide potential window of 1.4 V with high Coulombic efficiency, good rate and cycling stability, and improved energy density. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Novel star-like surfactant as dispersant for multi-walled carbon nanotubes in aqueous suspensions at high concentration

    Science.gov (United States)

    Qiao, Min; Ran, Qianping; Wu, Shishan

    2018-03-01

    A kind of novel surfactant with star-like molecular structure and terminated sulfonate was synthesized, and it was used as the dispersant for multi-walled carbon nanotubes (CNTs) in aqueous suspensions compared with a traditional single-chained surfactant. The star-like surfactant showed good dispersing ability for multi-walled CNTs in aqueous suspensions. Surface tension analysis, total organic carbon analysis, X-ray photoelectron spectroscopy, zeta potential, dynamic light scattering and transmission electron microscopy were performed to research the effect of star-like surfactant on the dispersion of multi-walled CNTs in aqueous suspensions. With the assistance of star-like surfactant, the CNTs could disperse well in aqueous suspension at high concentration of 50 g/L for more than 30 days, while the CNTs precipitated completely in aqueous suspension after 1 day without any dispersant or after 10 days with sodium 4-dodecylbenzenesulfonic acid as dispersant.

  9. Application of neural network to multi-dimensional design window search in reactor core design

    International Nuclear Information System (INIS)

    Kugo, Teruhiko; Nakagawa, Masayuki

    1999-01-01

    In the reactor core design, many parametric survey calculations should be carried out to decide an optimal set of basic design parameter values. They consume a large amount of computation time and labor in the conventional way. To support design work, we investigate a procedure to search efficiently a design window, which is defined as feasible design parameter ranges satisfying design criteria and requirements, in a multi-dimensional space composed of several basic design parameters. The present method is applied to the neutronics and thermal hydraulics fields. The principle of the present method is to construct the multilayer neural network to simulate quickly a response of an analysis code through a training process, and to reduce computation time using the neural network without parametric study using analysis codes. To verify the applicability of the present method to the neutronics and the thermal hydraulics design, we have applied it to high conversion water reactors and examined effects of the structure of the neural network and the number of teaching patterns on the accuracy of the design window estimated by the neural network. From the results of the applications, a guideline to apply the present method is proposed and the present method can predict an appropriate design window in a reasonable computation time by following the guideline. (author)

  10. Kinetic wall from Israel

    Energy Technology Data Exchange (ETDEWEB)

    Godolphin, D.

    1985-05-01

    An unusual solar mass wall is described. At the turn of a handle it can change from a solar energy collector to a heat-blocker. An appropriate name for it might be the rotating prism wall. An example of the moving wall is at work in an adobe test home in Sede Boqer. Behind a large south-facing window stand four large adobe columns that are triangular in plan. One face of each of them is painted black to absorb sunlight, a second is covered with panels of polystyrene insulation, and a third is painted to match the room decor. These columns can rotate. On winter nights, the insulated side faces the glass, keeping heat losses down. The same scheme works in summer to keep heat out of the house. Small windows provide ventilation.

  11. Demonstration with Energy and Daylighting Assessment of Sunlight Responsive Thermochromic (SRT) Window Systems

    Energy Technology Data Exchange (ETDEWEB)

    Broekhuis, Michael; Liposcak, Curtis; Witte, Michael; Henninger, Robert; Zhou, Xiaohui; Petzen, George; Buchanan, Michael; Kumar, Sneh

    2012-03-31

    Pleotint, LLC was able to successfully extrude thermochromic interlayer for use in the fenestration industry. Pleotint has developed a thermochromic sytem that requires two thermochromic colors to make a neutral color when in the tinted state. These two colors were assembled into a single interlayer called a tri-layer prelam by Crown Operations for use in the glass lamination industry. Various locations, orientations, and constructions of thermochromic windows were studied with funds from this contract. Locations included Australia, California, Costa Rica, Indiana, Iowa, Mexico. Installed orientations included vertical and skylight glazing applications. Various constructions included monolithic, double pane, triple pane constructions. A daylighting study was conducted at LinEl Signature. LinEl Signature has a conference room with a sylight roof system that has a west orientation. The existing LinEl Signature conference room had constant tint 40% VLT transparent skylights. Irradiance meters were installed on the interior and exterior sides of a constant tint skylight. After a month and a half of data collection, the irradiance meters were removed and the constant tint skylights were replaced with Pleotint thermochromic skylight windows. The irradiance meters were reinstalled in the same locations and irradiance data was collected. Both data sets were compared. The data showed that there was a linear relationship with exterior and interior irradiance for the existing constant tint skylights. The thermochromic skylights have a non-linear relationship. The thermochromic skylights were able to limit the amount of irradiance that passed through the thermochromic skylight. A second study of the LinEl Signature conference was performed using EnergyPlus to calculate the amount of Illuminance that passed through constant tint skylights as compared to thermochromic skylights. The constant tint skylights transmitted Illuminance is 2.8 times higher than the thermochromic

  12. Proximity and physical navigation in collaborative work with a multi-touch wall-display

    DEFF Research Database (Denmark)

    Jakobsen, Mikkel Rønne; Hornbæk, Kasper

    2012-01-01

    Multi-touch, wall-sized displays afford new forms of collaboration. Yet, most data on collaboration with multi-touch displays come from tabletop settings, where users often sit and where space is a limited resource. We study how two-person groups navigate in relation to a 2.8m!1.2m multi-touch di......-touch display with 24.8 megapixels and to each other when solving a sensemaking task on a document collection. The results show that users physically navigate to shift fluently among different parts of the display and between parallel and joint group work....

  13. Mechanical properties of multi-walled carbon nanotube/epoxy polysulfide nanocomposite

    International Nuclear Information System (INIS)

    Shirkavand Hadavand, Behzad; Mahdavi Javid, Kimya; Gharagozlou, Mehrnaz

    2013-01-01

    Highlights: ► Preparation of epoxy polysulfide nanocomposite. ► Multi-walled carbon nanotubes have been modified and dispersed in epoxy polysulfide matrix. ► Mechanical properties of MWNT/epoxy polysulfide have been studied. - Abstract: In this research, multi-walled carbon nanotubes (MWCNTs) were modified by acid functionalization (H 2 SO 4 :HNO 3 = 1:3 by volume) and then mechanical properties of reinforced epoxy polysulfide resin by the both pure and treated MWNTs have been evaluated. For achieving this goal, different weight percentages of pure and treated MWCNT (0.1–0.3 wt%) were dispersed in the epoxy polysulfide resin separately and then mixed with curing agent. Experimental results have shown significant difference between acid treated and untreated MWCNTs in mechanical properties of epoxy polysulfide nanocomposites. In nanocomposite with 0.1–0.3% acid treated MWCNTs we observed increase of Young’s modulus from 458 to 723 MPa, tensile strength from 5.29 to 8.83 MPa and fracture strain from 0.16% to 0.25%. For understanding the structure and morphology of nanocomposite, the dispersion states were studied using scanning electron microscopy (SEM) and field emission electron microscopy (FESEM). The results showed better dispersion of modified carbon nanotube than unmodified in polymeric matrix

  14. Optimising window parameters for energy efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Boland, J. [South Australia Univ., Adelaide, SA (Australia); Luther, M. [Deakin Univ., Geelong, VIC (Australia)

    1996-12-31

    Large north facing windows act a solar collectors, with the heat being stored in the building mass and being released later in the day. This study examines one of the elements of this paradigm, that increasing the size of equatorially facing windows necessarily improves the energy efficiency of a dwelling. This question and that of whether there is a case for using double glazing in Australia were examined for a number of locations ranging from cool temperate to warm temperate and for several types of construction from lightweight to heavyweight. Simulations were performed using the modelling tool Cheetah. It was found that the optimal window size on equatorially facing walls was smaller than expected for singly glazed windows. Double glazing was found to be effective in most situations and increased the optimum size of the window substantially. Changing the operational pattern of the house (specifically when cooling equipment may be employed) considerably affects conclusions about single and double glazing. (author). 3 tabs., 3 figs., 13 refs.

  15. Failure mechanism of shear-wall dominant multi-story buildings

    Science.gov (United States)

    Yuksel, S.B.; Kalkan, E.

    2008-01-01

    The recent trend in the building industry of Turkey as well as in many European countries is towards utilizing the tunnel form (shear-wall dominant) construction system for development of multi-story residential units. The tunnel form buildings diverge from other conventional reinforced concrete (RC) buildings due to the lack of beams and columns in their structural integrity. The vertical load-carrying members of these buildings are the structural-walls only, and the floor system is a flat plate. Besides the constructive advantages, tunnel form buildings provide superior seismic performance compared to conventional RC frame and dual systems as observed during the recent devastating earthquakes in Turkey (1999 Mw 7.4 Kocaeli, Mw 7.2 Duzce, and 2004 Mw 6.5 Bingol). With its proven earthquake performance, the tunnel form system is becoming the primary construction technique in many seismically active regions. In this study, a series of nonlinear analyses were conducted using finite element (FE) models to augment our understanding on their failure mechanism under lateral forces. In order to represent the nonlinear behavior adequately, The FE models were verified with the results of experimental studies performed on three dimensional (3D) scaled tunnel form building specimens. The results of this study indicate that the structural walls of tunnel form buildings may exhibit brittle flexural failure under lateral loading, if they are not properly reinforced. The global tension/compression couple triggers this failure mechanism by creating pure axial tension in the outermost shear-walls.

  16. Multi-Stable Conductance States in Metallic Double-Walled Carbon Nanotubes

    Directory of Open Access Journals (Sweden)

    Ci Lijie

    2009-01-01

    Full Text Available Abstract Electrical transport properties of individual metallic double-walled carbon nanotubes (DWCNTs were measured down to liquid helium temperature, and multi-stable conductance states were found in DWCNTs. At a certain temperature, DWCNTs can switch continuously between two or more electronic states, but below certain temperature, DWCNTs are stable only at one of them. The temperature for switching is always different from tube to tube, and even different from thermal cycle to cycle for the same tube. In addition to thermal activation, gate voltage scanning can also realize such switching among different electronic states. The multi-stable conductance states in metallic DWCNTs can be attributed to different Fermi level or occasional scattering centers induced by different configurations between their inner and outer tubes.

  17. Optical transmission of nematic liquid crystal 5CB doped by single-walled and multi-walled carbon nanotubes.

    Science.gov (United States)

    Lisetski, L N; Fedoryako, A P; Samoilov, A N; Minenko, S S; Soskin, M S; Lebovka, N I

    2014-08-01

    Comparative studies of optical transmission of single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs), dispersed in nematic liquid crystal matrix 5CB, were carried out. The data evidence violations of Beer-Lambert-Bouguer (BLB) law both in cell thickness and concentration dependencies. The most striking is the fact that optical transmission dependencies for SWCNTs and MWCNTs were quite different in the nematic phase, but they were practically indistinguishable in the isotropic phase. Monte Carlo simulations of the impact of aggregation on direct transmission and violation of BLB law were also done. The results were discussed accounting for the tortuous shape of CNTs, their physical properties and aggregation, as well as strong impact of perturbations of the nematic 5CB structure inside coils and in the vicinity of CNT aggregates.

  18. Assessment of wall friction model in multi-dimensional component of MARS with air–water cross flow experiment

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jin-Hwa [Nuclear Thermal-Hydraulic Engineering Laboratory, Seoul National University, Gwanak 599, Gwanak-ro, Gwanak-gu, Seoul 151-742 (Korea, Republic of); Korea Atomic Energy Research Institute, 989-111, Daedeok-daero, Yuseong-gu, Daejeon 305-600 (Korea, Republic of); Choi, Chi-Jin [Nuclear Thermal-Hydraulic Engineering Laboratory, Seoul National University, Gwanak 599, Gwanak-ro, Gwanak-gu, Seoul 151-742 (Korea, Republic of); Cho, Hyoung-Kyu, E-mail: chohk@snu.ac.kr [Nuclear Thermal-Hydraulic Engineering Laboratory, Seoul National University, Gwanak 599, Gwanak-ro, Gwanak-gu, Seoul 151-742 (Korea, Republic of); Euh, Dong-Jin [Korea Atomic Energy Research Institute, 989-111, Daedeok-daero, Yuseong-gu, Daejeon 305-600 (Korea, Republic of); Park, Goon-Cherl [Nuclear Thermal-Hydraulic Engineering Laboratory, Seoul National University, Gwanak 599, Gwanak-ro, Gwanak-gu, Seoul 151-742 (Korea, Republic of)

    2017-02-15

    Recently, high precision and high accuracy analysis on multi-dimensional thermal hydraulic phenomena in a nuclear power plant has been considered as state-of-the-art issues. System analysis code, MARS, also adopted a multi-dimensional module to simulate them more accurately. Even though it was applied to represent the multi-dimensional phenomena, but implemented models and correlations in that are one-dimensional empirical ones based on one-dimensional pipe experimental results. Prior to the application of the multi-dimensional simulation tools, however, the constitutive models for a two-phase flow need to be carefully validated, such as the wall friction model. Especially, in a Direct Vessel Injection (DVI) system, the injected emergency core coolant (ECC) on the upper part of the downcomer interacts with the lateral steam flow during the reflood phase in the Large-Break Loss-Of-Coolant-Accident (LBLOCA). The interaction between the falling film and lateral steam flow induces a multi-dimensional two-phase flow. The prediction of ECC flow behavior plays a key role in determining the amount of coolant that can be used as core cooling. Therefore, the wall friction model which is implemented to simulate the multi-dimensional phenomena should be assessed by multidimensional experimental results. In this paper, the air–water cross film flow experiments simulating the multi-dimensional phenomenon in upper part of downcomer as a conceptual problem will be introduced. The two-dimensional local liquid film velocity and thickness data were used as benchmark data for code assessment. And then the previous wall friction model of the MARS-MultiD in the annular flow regime was modified. As a result, the modified MARS-MultiD produced improved calculation result than previous one.

  19. Turning refuse plastic into multi-walled carbon nanotube forest

    Directory of Open Access Journals (Sweden)

    Eugene Oh, Jaegeun Lee, Seung-Ho Jung, Seungho Cho, Hye-Jin Kim, Sung-Hyun Lee, Kun-Hong Lee, Kyong-Hwa Song, Chi-Hoon Choi and Do Suck Han

    2012-01-01

    Full Text Available A novel and effective method was devised for synthesizing a vertically aligned carbon nanotube (CNT forest on a substrate using waste plastic obtained from commercially available water bottles. The advantages of the proposed method are the speed of processing and the use of waste as a raw material. A mechanism for the CNT growth was also proposed. The growth rate of the CNT forest was ~2.5 μm min−1. Transmission electron microscopy images indicated that the outer diameters of the CNTs were 20–30 nm on average. The intensity ratio of the G and D Raman bands was 1.27 for the vertically aligned CNT forest. The Raman spectrum showed that the wall graphitization of the CNTs, synthesized via the proposed method was slightly higher than that of commercially available multi-walled carbon nanotubes (MWCNTs. We expect that the proposed method can be easily adapted to the disposal of other refuse materials and applied to MWCNT production industries.

  20. Turning refuse plastic into multi-walled carbon nanotube forest

    Science.gov (United States)

    Oh, Eugene; Lee, Jaegeun; Jung, Seung-Ho; Cho, Seungho; Kim, Hye-Jin; Lee, Sung-Hyun; Lee, Kun-Hong; Song, Kyong-Hwa; Choi, Chi-Hoon; Han, Do Suck

    2012-01-01

    A novel and effective method was devised for synthesizing a vertically aligned carbon nanotube (CNT) forest on a substrate using waste plastic obtained from commercially available water bottles. The advantages of the proposed method are the speed of processing and the use of waste as a raw material. A mechanism for the CNT growth was also proposed. The growth rate of the CNT forest was ∼2.5 μm min−1. Transmission electron microscopy images indicated that the outer diameters of the CNTs were 20–30 nm on average. The intensity ratio of the G and D Raman bands was 1.27 for the vertically aligned CNT forest. The Raman spectrum showed that the wall graphitization of the CNTs, synthesized via the proposed method was slightly higher than that of commercially available multi-walled carbon nanotubes (MWCNTs). We expect that the proposed method can be easily adapted to the disposal of other refuse materials and applied to MWCNT production industries. PMID:27877482

  1. Toxicological effects of multi-wall carbon nanotubes in rats

    International Nuclear Information System (INIS)

    Liu Aihong; Sun Kangning; Yang, Jiafeng; Zhao Dongmei

    2008-01-01

    The aim of this study was to evaluate the lung toxicity of multi-wall carbon nanotubes (MWCNTs). The present work exposed MWCNTs into the rats in intratracheal instillation administration modes. We systematically studied the distribution of nanoparticles in vivo, target organs and time-effects of nanotoxicity, dose-effects of nanotoxicity, etc. These results indicate that under the conditions of this test, pulmonary exposures to MWCNTs in rats by intratracheal instillation produced a series of multiple lesions in a dose-dependent and time-dependent manner, evidence of a foreign tissue body reaction.

  2. Toxicological effects of multi-wall carbon nanotubes in rats

    Energy Technology Data Exchange (ETDEWEB)

    Liu Aihong; Sun Kangning, E-mail: Sunkangning@sdu.edu.cn; Yang, Jiafeng [Engineering Ceramics Key Laboratory of Shandong Province, Material Science and Engineering Institute, Shandong University, Key Laboratory of Liquid Structure and Heredity of Materials ministry of Education (China); Zhao Dongmei [The Second Hospital of Shandong University (China)

    2008-12-15

    The aim of this study was to evaluate the lung toxicity of multi-wall carbon nanotubes (MWCNTs). The present work exposed MWCNTs into the rats in intratracheal instillation administration modes. We systematically studied the distribution of nanoparticles in vivo, target organs and time-effects of nanotoxicity, dose-effects of nanotoxicity, etc. These results indicate that under the conditions of this test, pulmonary exposures to MWCNTs in rats by intratracheal instillation produced a series of multiple lesions in a dose-dependent and time-dependent manner, evidence of a foreign tissue body reaction.

  3. Decorating multi-walled carbon nanotubes with quantum dots for construction of multi-color fluorescent nanoprobes

    International Nuclear Information System (INIS)

    Jia Nengqin; Lian Qiong; Tian Zhong; Yin Min; Che, Shouhui; Shen Hebai; Duan Xin; Jing Lihong; Gao Mingyuan

    2010-01-01

    Novel multi-color fluorescent nanoprobes were prepared by electrostatically assembling differently sized CdTe quantum dots on polyethylenimine (PEI) functionalized multi-walled carbon nanotubes (MWNTs). The structural and optical properties of the nano-assemblies (MWNTs-PEI-CdTe) were characterized by transmission electron microscopy (TEM), electron diffraction spectra (EDS), Raman spectroscopy, confocal microscopy and photoluminescence spectroscopy (PL), respectively. Electrochemical impedance spectroscopy (EIS) was also applied to investigate the electrostatic assembling among oxidized MWNTs, PEI and CdTe. Furthermore, confocal fluorescence microscopy was used to monitor the nano-assemblies' delivery into tumor cells. It was found that the nano-assemblies exhibit efficient intracellular transporting and strong intracellular tracking. These properties would make this luminescent nano-assembly an excellent building block for the construction of intracellular nanoprobes, which could hold great promise for biomedical applications.

  4. Enhancement of heat transfer for thermal energy storage application using stearic acid nanocomposite with multi-walled carbon nanotubes

    International Nuclear Information System (INIS)

    Li, TingXian; Lee, Ju-Hyuk; Wang, RuZhu; Kang, Yong Tae

    2013-01-01

    A latent heat storage nanocomposite made of stearic acid (SA) and multi-walled carbon nanotube (MWCNT) is prepared for thermal energy storage application. The thermal properties of the SA/MWCNT nanocomposite are characterized by SEM (scanning electron microscopy) and DSC (differential scanning calorimeter) analysis techniques, and the effects of different volume fractions of MWCNT on the heat transfer enhancement and thermal performance of stearic acid are investigated during the charging and discharging phases. The SEM analysis shows that the additive of MWCNT is uniformly distributed in the phase change material of stearic acid, and the DSC analysis reveals that the melting point of SA/MWCNT nanocomposite shifts to a lower temperature during the charging phase and the freezing point shifts to a higher temperature during the discharging phase when compared with the pure stearic acid. The experimental results show that the addition of MWCNT can improve the thermal conductivity of stearic acid effectively, but it also weakens the natural convection of stearic acid in liquid state. In comparison with the pure stearic acid, the charging rate can be decreased by about 50% while the discharging rate can be improved by about 91% respectively by using the SA/5.0% MWCNT nanocomposite. It appears that the MWCNT is a promising candidate for enhancing the heat transfer performance of latent heat thermal energy storage system. - Highlights: • A nanocomposite made of stearic acid and multi-walled carbon nanotube is prepared for thermal energy storage application. • Effects of multi-walled carbon nanotube on the thermal performance of the nanocomposite are investigated. • Multi-walled carbon nanotube enhances the thermal conductivity but weakens the natural convection of stearic acid. • Discharging/charging rates of stearic acid are increased/decreased by using multi-walled carbon nanotube

  5. Eradicating group A streptococcus bacteria and biofilms using functionalised multi-wall carbon nanotubes.

    Science.gov (United States)

    Levi-Polyachenko, Nicole; Young, Christie; MacNeill, Christopher; Braden, Amy; Argenta, Louis; Reid, Sean

    2014-11-01

    The aim of this study was to demonstrate that multi-wall carbon nanotubes can be functionalised with antibodies to group A streptoccocus (GAS) for targeted photothermal ablation of planktonic and biofilm residing bacteria. Antibodies for GAS were covalently attached to carboxylated multi-wall carbon nanotubes and incubated with either planktonic or biofilm GAS. Bacterium was then exposed to 1.3 W/cm(2) of 800 nm light for 10-120 s, and then serially diluted onto agar plates from which the number of colony forming units was determined. Photothermal ablation of GAS on the surface of full thickness ex vivo porcine skin and histological sectioning were done to examine damage in adjacent tissue. Approximately 14% of the GAS antibody-functionalised nanotubes attached to the bacterium, and this amount was found to be capable of inducing photothermal ablation of GAS upon exposure to 1.3 W/cm(2) of 800 nm light. Cell viability was not decreased upon exposure to nanotubes or infrared light alone. Compared to carboxylated multi-wall carbon nanotubes, antibody-labelled nanotubes enhanced killing in both planktonic and biofilm GAS in conjunction with infrared light. Analysis of GAS photothermally ablated in direct contact with ex vivo porcine skin shows that heat sufficient for killing GAS remains localised and does not cause collateral damage in tissue adjacent to the treated area. The results of this study support the premise that carbon nanotubes may be effectively utilised as highly localised photothermal agents with the potential for translation into the clinical treatment of bacterial infections of soft tissue.

  6. Proper understanding of relevant articles in RCC-M and PANE G-7-002

    International Nuclear Information System (INIS)

    Sun Zaozhan

    2005-01-01

    The French code, 'Design and construction rules for mechanical components of PWR nuclear island' RCC-M and the Russian code 'Regulations for strength analysis of equipment and pipelines of atomic power plants' PANE G-7-002, both for nuke plant design, are sometimes used in China, and discrepancies in understanding some articles of such foreign design codes will some times give different conclusions as 'acceptable' or 'unacceptable' the concerned material or product. Section IV of RCC-M concerns with qualification and performance of welding operations. Article S 3150 in this section covers the retesting procedures and article S 3152 in it relates to destructive tests. One sentence in Article S 3152 reads like this, 'Where an unsatisfactory result is due to the poor execution of the test or the presence of a defect in the specimen, the relevant result must be discarded and the test shall be repeated.' The 'presence of a defect' arose discrepancies in understanding the sentence because there is no definition in RCC-M to clarify their scopes such as how big a defect should be considered as a 'defect' that can invalidate the test results. Section 5.5 of PANE G-7-002 concerns the determination of critical brittle temperature. It stipulates that critical brittle temperature T k is a temperature at which the impact strength values must be higher than the specified ones. The specified criterion values of impact strength are related to the yield strength but it is not quite definite that the yield strength values in the table should be the documented minimum values for different materials or that they should be the tested results of the concerned lots of materials the specimen represents. The two different understandings of the yield strength values will sometimes give contrary conclusions. This paper introduces the different opinions in understanding the code texts, makes clear what it supports, and states in detail the reasons it so believes. (authors)

  7. Rhinitis, Asthma and Respiratory Infections among Adults in Relation to the Home Environment in Multi-Family Buildings in Sweden

    Science.gov (United States)

    Wang, Juan; Engvall, Karin; Smedje, Greta; Norbäck, Dan

    2014-01-01

    Risk factors for rhinitis, asthma and respiratory infections in the home environment were studied by a questionnaire survey. Totally 5775 occupants (≥18 years old) from a stratified random sample of multi-family buildings in Sweden participated (46%). 51.0% had rhinitis in the last 3 months (current rhinitis); 11.5% doctor diagnosed asthma; 46.4% respiratory infections in the last 3 months and 11.9% antibiotic medication for respiratory infections in the last 12 months. Associations between home environment and health were analyzed by multiple logistic regression, controlling for gender, age and smoking and mutual adjustment. Buildings constructed during 1960–1975 were risk factors for day time breathlessness (OR = 1.53, 95%CI 1.03–2.29). And those constructed during 1976–1985 had more current rhinitis (OR = 1.43, 95%CI 1.12–1.84) and respiratory infections (OR = 1.46, 95%CI 1.21–1.78). Cities with higher population density had more current rhinitis (p = 0.008) and respiratory infections (pBuilding dampness was a risk factor for wheeze (OR = 1.42, 95%CI 1.08–1.86) and day time breathlessness (OR = 1.57, 95%CI 1.09–2.27). Building dampness was a risk factor for health among those below 66 years old. Odor at home was a risk factor for doctor diagnosed asthma (OR = 1.49, 95%CI 1.08–2.06) and current asthma (OR = 1.52, 95%CI 1.03–2.24). Environmental tobacco smoke (ETS) was a risk factor for current asthma (OR = 1.53, 95%CI 1.09–2.16). Window pane condensation was a risk factor for antibiotic medication for respiratory infections (OR = 1.41, 95%CI 1.10–1.82). In conclusion, rhinitis, asthma and respiratory infections were related to a number of factors in the home environment. Certain building years (1961–1985), building dampness, window pane condensation and odor in the dwelling may be risk factors. PMID:25136984

  8. Surfactive stabilization of multi-walled carbon nanotube dispersions with dissolved humic substances

    Energy Technology Data Exchange (ETDEWEB)

    Chappell, Mark A. [Environmental Laboratory, Engineering Research and Development Center, US Army Corps of Engineers, 3909 Halls Ferry Road, Vicksburg, MS 39180 (United States)], E-mail: mark.a.chappell@usace.army.mil; George, Aaron J.; Dontsova, Katerina M.; Porter, Beth E. [SpecPro, Inc., 4815 Bradford Drive, Suite 201, Huntsville, AL 35805 (United States); Price, Cynthia L. [Environmental Laboratory, Engineering Research and Development Center, US Army Corps of Engineers, 3909 Halls Ferry Road, Vicksburg, MS 39180 (United States); Zhou Pingheng; Morikawa, Eizi [J. Bennett Johnston Sr. Center for Advanced Microstructures and Devices, Louisiana State University, 6980 Jefferson Highway, Baton Rouge, LA 70806 (United States); Kennedy, Alan J.; Steevens, Jeffery A. [Environmental Laboratory, Engineering Research and Development Center, US Army Corps of Engineers, 3909 Halls Ferry Road, Vicksburg, MS 39180 (United States)

    2009-04-15

    Soil humic substances (HS) stabilize carbon nanotube (CNT) dispersions, a mechanism we hypothesized arose from the surfactive nature of HS. Experiments dispersing multi-walled CNT in solutions of dissolved Aldrich humic acid (HA) or water-extractable Catlin soil HS demonstrated enhanced stability at 150 and 300 mg L{sup -1} added Aldrich HA and Catlin HS, respectively, corresponding with decreased CNT mean particle diameter (MPD) and polydispersivity (PD) of 250 nm and 0.3 for Aldrich HA and 450 nm and 0.35 for Catlin HS. Analogous trends in MPD and PD were observed with addition of the surfactants Brij 35, Triton X-405, and SDS, corresponding to surfactant sorption maximum. NEXAFS characterization showed that Aldrich HA contained highly surfactive domains while Catlin soil possessed a mostly carbohydrate-based structure. This work demonstrates that the chemical structure of humic materials in natural waters is directly linked to their surfactive ability to disperse CNT released into the environment. - Suspensions of multi-walled carbon nanotubes are stabilized by relatively low concentrations of dissolved humic substances in solution through surfactive mechanisms.

  9. Surfactive stabilization of multi-walled carbon nanotube dispersions with dissolved humic substances

    International Nuclear Information System (INIS)

    Chappell, Mark A.; George, Aaron J.; Dontsova, Katerina M.; Porter, Beth E.; Price, Cynthia L.; Zhou Pingheng; Morikawa, Eizi; Kennedy, Alan J.; Steevens, Jeffery A.

    2009-01-01

    Soil humic substances (HS) stabilize carbon nanotube (CNT) dispersions, a mechanism we hypothesized arose from the surfactive nature of HS. Experiments dispersing multi-walled CNT in solutions of dissolved Aldrich humic acid (HA) or water-extractable Catlin soil HS demonstrated enhanced stability at 150 and 300 mg L -1 added Aldrich HA and Catlin HS, respectively, corresponding with decreased CNT mean particle diameter (MPD) and polydispersivity (PD) of 250 nm and 0.3 for Aldrich HA and 450 nm and 0.35 for Catlin HS. Analogous trends in MPD and PD were observed with addition of the surfactants Brij 35, Triton X-405, and SDS, corresponding to surfactant sorption maximum. NEXAFS characterization showed that Aldrich HA contained highly surfactive domains while Catlin soil possessed a mostly carbohydrate-based structure. This work demonstrates that the chemical structure of humic materials in natural waters is directly linked to their surfactive ability to disperse CNT released into the environment. - Suspensions of multi-walled carbon nanotubes are stabilized by relatively low concentrations of dissolved humic substances in solution through surfactive mechanisms

  10. Highly Stable and Flexible Pressure Sensors with Modified Multi-Walled Carbon Nanotube/Polymer Composites for Human Monitoring.

    Science.gov (United States)

    He, Yin; Ming, Yue; Li, Wei; Li, Yafang; Wu, Maoqi; Song, Jinzhong; Li, Xiaojiu; Liu, Hao

    2018-04-26

    A facile method for preparing an easy processing, repeatable and flexible pressure sensor was presented via the synthesis of modified multi-walled carbon nanotubes (m-MWNTs) and polyurethane (PU) films. The surface modification of multi-walled carbon nanotubes (MWNTs) simultaneously used a silane coupling agent (KH550) and sodium dodecyl benzene sulfonate (SDBS) to improve the dispersibility and compatibility of the MWNTs in a polymer matrix. The electrical property and piezoresistive behavior of the m-MWNT/PU composites were compared with raw multi-walled carbon nanotube (raw MWNT)/PU composites. Under linear uniaxial pressure, the m-MWNT/PU composite exhibited 4.282%kPa −1 sensitivity within the pressure of 1 kPa. The nonlinear error, hysteresis error and repeatability error of the piezoresistivity of m-MWNT/PU decreased 9%, 16.72% and 54.95% relative to raw MWNT/PU respectively. Therefore, the piezoresistive response of m-MWNT/PU had better stability than that of raw MWNT/PU composites. The m-MWNT/PU sensors could be utilized in wearable devices for body movement detection, monitoring of respiration and pressure detection in garments.

  11. Key design features of multi-vacuum glazing for windows: A review

    Directory of Open Access Journals (Sweden)

    Ali Hassan

    2017-01-01

    Full Text Available The use of vacuum glazed windows is increasing due to their application in mod-ern building design. Among various types of vacuum glazed windows reported in literature, thermal transmittance of single glass sheet (conventional window i. e 6 W/m2k is reduced by 66 and 77% using air filled double glazed and air filled triple glazed windows, respectively. Using low emittance coatings thermal transmittance of double glazed windows is reduced by 53%, however it offsets the visibility by reduc-ing light transmittance by 5%. Stresses due to temperature/pressure gradients if not eliminated may lead to reduction in service life of vacuum glazed windows. Vacuum created between the glass sheets is used to reduce conductive heat transfer. Degrada-tion in the vacuum is caused by number of factors such as, permeation of gaseous molecules through glass sheets, leakage through sealing, thermal/optical desorption, and photo-fragmentation of organic species have been critically reviewed and future trends are outlined.

  12. Crystallization and melting behavior of multi-walled carbon nanotube-reinforced nylon-6 composites

    NARCIS (Netherlands)

    Phang, In Yee; Ma, Jianhua; Shen, Lu; Liu, Tianxi; Zhang, Wei-De

    2006-01-01

    The crystallization and melting behavior of neat nylon-6 (PA6) and multi-walled carbon nanotubes (MWNTs)/PA6 composites prepared by simple melt-compounding was comparatively studied. Differential scanning calorimetry (DSC) results show two crystallization exotherms (TCC, 1 and TCC, 2) for PA6/MWNTs

  13. Spray deposition of steam treated and functionalized single-walled and multi-walled carbon nanotube films for supercapacitors

    International Nuclear Information System (INIS)

    Zhao Xin; Chu, Bryan T T; Johnston, Colin; Sykes, John M; Grant, Patrick S; Ballesteros, Belen; Wang Weiliang

    2009-01-01

    Steam purified, carboxylic and ester functionalized single-walled carbon nanotube (SWNT) and multi-walled carbon nanotube (MWNT) films with homogeneous distribution and flexible control of thickness and area were fabricated on polymeric and metallic substrates using a modified spray deposition technique. By employing a pre-sprayed polyelectrolyte, the adhesion of the carbon nanotube (CNT) films to the substrates was significantly enhanced by electrostatic interaction. Carboxylic and ester functionalization improved electrochemical performance when immersed in 0.1 M H 2 SO 4 and the specific capacitance reached 155 and 77 F g -1 for carboxylic functionalized SWNT and MWNT films respectively. Compared with existing techniques such as hot pressing, vacuum filtration and dip coating, the ambient pressure spray deposition technique is suggested as particularly well suited for preparing CNT films at large scale for applications including providing electrodes for electrochemical supercapacitors and paper batteries.

  14. ELECTROPHORETIC DEPOSITION OF TIO2-MULTI-WALLED CARBON NANOTUBE COMPOSITE COATINGS: MORPHOLOGICAL STUDY

    Directory of Open Access Journals (Sweden)

    M. S. MAHMOUDI JOZEE

    2016-09-01

    Full Text Available A homogenous TiO2 / multi-walled carbon nanotubes(MWCNTs composite film were prepared by electrophoretic co-deposition from organic suspension on a stainless steel substrate.  In this study, MWCNTs was incorporated to the coating because of their long structure and their capability to be functionalized by different inorganic groups on the surface. FTIR spectroscopy showed the existence of carboxylic groups on the modified carbon nanotubes surface. The effect of applied electrical fields, deposition time and concentration of nanoparticulates on coatings morphology were investigated by scanning electron microscopy. It was found that combination of MWCNTs within TiO2 matrix eliminating micro cracks presented on TiO2 coating. Also, by increasing the deposition voltages, micro cracks were increased. SEM observation of the coatings revealed that TiO2/multi-walled carbon nanotubes coatings produced from optimized electric field was uniform and had good adhesive to the substrate.

  15. Microwave absorbing properties of polyaniline/multi-walled carbon nanotube composites with various polyaniline contents

    International Nuclear Information System (INIS)

    Ting, T.H.; Jau, Y.N.; Yu, R.P.

    2012-01-01

    Polyaniline/multi-walled carbon nanotube (PANI/MWNT) composites were synthesized using in situ polymerization at different aniline/multi-walled carbon nanotube weight ratios (Ani/MWNT = 1/2, 1/1, 2/1 and 3/1) and introduced into an epoxy resin to act as a microwave absorber. The spectroscopic characterization of the process of formation of PANI/MWNT composites were studied using Fourier transform infrared spectroscopy, an ultraviolet-visible spectrophotometer, X-ray diffraction, scanning electron microscopy, transmission electron microscopy and electron spin resonance. The microwave absorbing properties were investigated by measuring complex permittivity, complex permeability and reflection loss in the 2-18 and 18-40 GHz microwave frequency range, using the free space method. The results showed that the addition of PANI was useful for achieving a large absorption over a wide frequency range, especially for higher frequency values.

  16. Effects of nitrogen-doped multi-walled carbon nanotubes compared to pristine multi-walled carbon nanotubes on human small airway epithelial cells.

    Science.gov (United States)

    Mihalchik, Amy L; Ding, Weiqiang; Porter, Dale W; McLoughlin, Colleen; Schwegler-Berry, Diane; Sisler, Jennifer D; Stefaniak, Aleksandr B; Snyder-Talkington, Brandi N; Cruz-Silva, Rodolfo; Terrones, Mauricio; Tsuruoka, Shuji; Endo, Morinobu; Castranova, Vincent; Qian, Yong

    2015-07-03

    Nitrogen-doped multi-walled carbon nanotubes (ND-MWCNTs) are modified multi-walled carbon nanotubes (MWCNTs) with enhanced electrical properties that are used in a variety of applications, including fuel cells and sensors; however, the mode of toxic action of ND-MWCNT has yet to be fully elucidated. In the present study, we compared the interaction of ND-MWCNT or pristine MWCNT-7 with human small airway epithelial cells (SAEC) and evaluated their subsequent bioactive effects. Transmission electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, and X-ray diffraction suggested the presence of N-containing defects in the lattice of the nanotube. The ND-MWCNTs were determined to be 93.3% carbon, 3.8% oxygen, and 2.9% nitrogen. A dose-response cell proliferation assay showed that low doses of ND-MWCNT (1.2μg/ml) or MWCNT-7 (0.12μg/ml) increased cellular proliferation, while the highest dose of 120μg/ml of either material decreased proliferation. ND-MWCNT and MWCNT-7 appeared to interact with SAEC at 6h and were internalized by 24h. ROS were elevated at 6 and 24h in ND-MWCNT exposed cells, but only at 6h in MWCNT-7 exposed cells. Significant alterations to the cell cycle were observed in SAEC exposed to either 1.2μg/ml of ND-MWCNT or MWCNT-7 in a time and material-dependent manner, possibly suggesting potential damage or alterations to cell cycle machinery. Our results indicate that ND-MWCNT induce effects in SAEC over a time and dose-related manner which differ from MWCNT-7. Therefore, the physicochemical characteristics of the materials appear to alter their biological effects. Published by Elsevier Ireland Ltd.

  17. Controlling the number of walls in multi walled carbon nanotubes/alumina hybrid compound via ball milling of precipitate catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Nosbi, Norlin [School of Materials and Mineral Resources Engineering, Engineering Campus, Universiti Sains Malaysia (USM), 14300 Nibong Tebal, Seberang Perai Selatan, Pulau Pinang (Malaysia); Akil, Hazizan Md, E-mail: hazizan@usm.my [School of Materials and Mineral Resources Engineering, Engineering Campus, Universiti Sains Malaysia (USM), 14300 Nibong Tebal, Seberang Perai Selatan, Pulau Pinang (Malaysia); Cluster for Polymer Composite (CPC), Science and Engineering Research Centre, Engineering Campus, Universiti Sains Malaysia (USM), 14300 Nibong Tebal, Seberang Perai Selatan, Pulau Pinang (Malaysia)

    2015-06-15

    Graphical abstract: - Highlights: • We report that, to manipulate carbon nanotubes geometry and number of walls are by controlling the precipitate catalyst size. • Number of walls and geometry effects depend on the milling time of the precipitate catalyst. • Increasing milling of time will decrease the carbon nanotubes number of walls. • Increasing milling of time will increase the carbon nanotubes thermal conductivity. - Abstract: This paper reports the influence of milling time on the structure and properties of the precipitate catalyst of multi walled carbon nanotubes (MWCNT)/alumina hybrid compound, produced through the chemical vapour deposition (CVD) process. For this purpose, light green precipitate consisted of aluminium, nickel(II) nitrate hexahydrate and sodium hydroxide mixture was placed in a planetary mill equipped with alumina vials using alumina balls at 300 rpm rotation speed for various milling time (5–15 h) prior to calcinations and CVD process. The compound was characterized using various techniques. Based on high-resolution transmission electron microscopy analysis, increasing the milling time up to 15 h decreased the diameter of MWCNT from 32.3 to 13.1 nm. It was noticed that the milling time had a significant effect on MWCNT wall thickness, whereby increasing the milling time from 0 to 15 h reduced the number of walls from 29 to 12. It was also interesting to note that the carbon content increased from 23.29 wt.% to 36.37 wt.% with increasing milling time.

  18. Aerodynamic window for a laser fusion device

    International Nuclear Information System (INIS)

    Masuda, Wataru

    1983-01-01

    Since the window of a laser system absorbs a part of the laser energy, the output power is determined by the characteristics of the window. The use of an aerodynamic window has been studied. The required characteristics are to keep the large pressure difference. An equation of motion of a vortex was presented and analyzed. The operation power of the system was studied. A multi-stage aerodynamic window was proposed to reduce the power. When the jet flow of 0.3 of the Mach number is used, the operation power will be several Megawatt, and the length of an optical path will be about 100 m. (Kato, T.)

  19. A Temperature Window for the Synthesis of Single-Walled Carbon Nanotubes by Catalytic Chemical Vapor Deposition of CH4over Mo2-Fe10/MgO Catalyst

    Directory of Open Access Journals (Sweden)

    Yu Ouyang

    2009-01-01

    Full Text Available Abstract A temperature window for the synthesis of single-walled carbon nanotubes by catalytic chemical vapor deposition of CH4over Mo2-Fe10/MgO catalyst has been studied by Raman spectroscopy. The results showed that when the temperature is lower than 750 °C, there were few SWCNTs formed, and when the temperature is higher than 950 °C, mass amorphous carbons were formed in the SWCNTs bundles due to the self-decomposition of CH4. The temperature window of SWCNTs efficient growth is between 800 and 950 °C, and the optimum growth temperature is about 900 °C. These results were supported by transmission electron microscope images of samples formed under different temperatures. The temperature window is important for large-scale production of SWCNTs by catalytic chemical vapor deposition method.

  20. 49 CFR Figure 2 to Subpart B of... - Example of a Multi-Level Car Complying with Window Location and Staggering Requirements-§§ 238...

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Example of a Multi-Level Car Complying with Window Location and Staggering Requirements-§§ 238.113 and 238.114 2 Figure 2 to Subpart B of Part 238.... 238, Subpt. B, Fig. 2 Figure 2 to Subpart B of Part 238—Example of a Multi-Level Car Complying with...

  1. Flow induced vibration and stability analysis of multi wall carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Kyung Jae [Agency for Defense Development, Daejeon (Korea, Republic of); Choi, Jong Woon [Korean Intellectual Property Office, Daejeon (Korea, Republic of); Kim, Sung Kyun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Song, Oh Seop [Chungnam National Univ., Daejeon (Korea, Republic of)

    2012-12-15

    The free vibration and flow induced flutter instability of cantilever multi wall carbon nanotubes conveying fluid are investigated and the nanotubes are modeled as thin-walled beams. The non-classical effects of the transverse shear, rotary inertia, warping inhibition, and van der Waals forces between two walls are incorporated into the structural model. The governing equations and associated boundary conditions are derived using Hamilton's principle. A numerical analysis is carried out by using the extended Galerkin method, which enables us to obtain more accurate solutions compared to the conventional Galerkin method. Cantilevered carbon nanotubes are damped with decaying amplitude for a flow velocity below a certain critical value. However, beyond this critical flow velocity, flutter instability may occur. The variations in the critical flow velocity with respect to both the radius ratio and length of the carbon nanotubes are investigated and pertinent conclusions are outlined. The differences in the vibration and instability characteristics between the Timoshenko beam theory and Euler beam theory are revealed. A comparative analysis of the natural frequencies and flutter characteristics of MWCNTs and SWCNTs is also performed.

  2. Comparative Study of Single- and Multi-Wall Carbon Nanotubes with Application in Cerebral Aneurysm

    Directory of Open Access Journals (Sweden)

    Rodica-Mariana Ion

    2011-01-01

    Full Text Available Helping improve humanity is one of the promises of nanotech-
    nology and nanomedicine. This paper will highlight some of the research findings in the nanomedicine area by testing some single- and multi-walls carbon nanotubues in rats cerebral aneurisms.

  3. Oh, What a Pane! An Inquiry Based on Activity with a Mathematical Approach to Investigation Windows on Earth...and in Space. Teacher Guide

    Science.gov (United States)

    Baker, Marshalyn; Mailhot, Michele; Graff, Paige Valderrama

    2010-01-01

    This is a teacher's guide to assist teachers in developing modules on windows for use in both earth and space and astronaut photographs. Activities incorporating mathematical exercises are suggested for grades five through ten.

  4. The Interaction Features of the Multi-Level Retaining Walls with Soil Mass

    Science.gov (United States)

    Boyko, Igor; Skochko, Liudmyla; Zhuk, Veronica

    2017-09-01

    The interaction features of multi-level retaining walls with soil base were researched by changing their geometric parameters and locality at the plan. During excavation of deep foundation pits it is important to choose the type of constructions which influences on the horizontal displacements. The distance between the levels of retaining walls should be based on the results of numerical modelling. The objective of this paper is to present a comparison between the data of numerical simulations and the results of the in-situ lateral tests of couple piles. The problems have been solved by using the following soil models: Coulomb-Mohr model; model, which is based on the dilatation theory; elastic-plastic model with variable stiffness parameters.

  5. Multi-walled carbon nanotube physicochemical properties predict pulmonary inflammation and genotoxicity

    DEFF Research Database (Denmark)

    Poulsen, Sarah S.; Jackson, Petra; Kling, Kirsten

    2016-01-01

    Lung deposition of multi-walled carbon nanotubes (MWCNT) induces pulmonary toxicity. Commercial MWCNT vary greatly in physicochemical properties and consequently in biological effects. To identify determinants of MWCNT-induced toxicity, we analyzed the effects of pulmonary exposure to 10 commerci...... diameter was associated with increased genotoxicity. This study provides information on possible toxicity-driving physicochemical properties of MWCNT. The results may contribute to safe-by-design manufacturing of MWCNT, thereby minimizing adverse effects....

  6. Development and production of radiation shielding window (RSW) glass: Indian scenario

    International Nuclear Information System (INIS)

    Phani, K.K.

    2006-01-01

    Nuclear energy/power and its peaceful applications play an ever increasing role in India. Irradiated nuclear fuels, irradiated structural materials from reactors, nuclear wastes and radio-isotopes emit high energy gamma radiations which are extremely health hazardous. These materials are handled remotely by manipulators inside the hot cells, which are constructed by shielding materials such as lead and concrete walls. The direct visual control of processes in the hot cells during operation demands the windows in the radiation shielding walls. These windows must provide the clear viewing but yet ensure the good protection to the working personnel from the high energy radiation

  7. Renovation and design of double casement windows with regard to the occurrence of water vapour condensation or mould on the interior surface of the window jamb

    Science.gov (United States)

    Kudrnacova, L.; Balik, L.

    2017-10-01

    The condensation of water vapour on the interior surface is an indicator of construction dysfunction or ignoring of the surroundings temperature and relative humidity. This paper deals with analysis of the occurrence of condensation on the jamb of double casement windows (windows with two window casements). More precisely, this is a surface in the interior where water vapour condensation or mould occur. For the renovation of existing double casement windows, there are different solutions based on window design: application of double insulating glazing on the interior window casement, application of double insulating glazing on the exterior casement, or installation of a simple window. We first describe measurement of an existing double casement window located in a mountain cottage. Second, the results and comparison of 2D thermal model of different types of double casement window construction. Also, the external insulation of the peripheral wall was included in the model.

  8. Multi-walled Carbon Nanotubes/Graphite Nanosheets Modified Glassy Carbon Electrode for the Simultaneous Determination of Acetaminophen and Dopamine.

    Science.gov (United States)

    Zhang, Susu; He, Ping; Zhang, Guangli; Lei, Wen; He, Huichao

    2015-01-01

    Graphite nanosheets prepared by thermal expansion and successive sonication were utilized for the construction of a multi-walled carbon nanotubes/graphite nanosheets based amperometric sensing platform to simultaneously determine acetaminophen and dopamine in the presence of ascorbic acid in physiological conditions. The synergistic effect of multi-walled carbon nanotubes and graphite nanosheets catalyzed the electrooxidation of acetaminophen and dopamine, leading to a remarkable potential difference up to 200 mV. The as-prepared modified electrode exhibited linear responses to acetaminophen and dopamine in the concentration ranges of 2.0 × 10(-6) - 2.4 × 10(-4) M (R = 0.999) and 2.0 × 10(-6) - 2.0 × 10(-4) M (R = 0.998), respectively. The detection limits were down to 2.3 × 10(-7) M for acetaminophen and 3.5 × 10(-7) M for dopamine (S/N = 3). Based on the simple preparation and prominent electrochemical properties, the obtained multi-walled carbon nanotubes/graphite nanosheets modified electrode would be a good candidate for the determination of acetaminophen and dopamine without the interference of ascorbic acid.

  9. The multi-depot electric vehicle location routing problem with time windows

    Directory of Open Access Journals (Sweden)

    Juan Camilo Paz

    2018-01-01

    Full Text Available In this paper, the Multi-Depot Electric Vehicle Location Routing Problem with Time Windows (MDVLRP is addressed. This problem is an extension of the MDVLRP, where electric vehicles are used instead of internal combustion engine vehicles. The recent development of this model is explained by the advantages of this technology, such as the diminution of carbon dioxide emissions, and the support that they can provide to the design of the logistic and energy-support structure of electric vehicle fleets. There are many models that extend the classical VRP model to take electric vehicles into consideration, but the multi-depot case for location-routing models has not been worked out yet. Moreover, we consider the availability of two energy supply technologies: the “Plug-in” Conventional Charge technology, and Battery Swapping Stations; options in which the recharging time is a function of the amount of energy to charge and a fixed time, respectively. Three models are proposed: one for each of the technologies mentioned above, and another in which both options are taken in consideration. The models were solved for small scale instances using C++ and Cplex 12.5. The results show that the models can be used to design logistic and energy-support structures, and compare the performance of the different options of energy supply, as well as measure the impact of these decisions on the overall distance traveled or other optimization objectives that could be worked on in the future.

  10. Exchange of Surfactant by Natural Organic Matter on the Surfaces of Multi-Walled Carbon Nanotubes

    Science.gov (United States)

    The increasing production and applications of multi-walled carbon nanotubes (MWCNTs) have elicited concerns regarding their release and potential adverse effects in the environment. To form stable aqueous MWCNTs suspensions, surfactants are often employed to facilitate dispersion...

  11. Inferior hilar window on lateral chest radiographs

    International Nuclear Information System (INIS)

    Park, C.K.; Webb, W.R.; Klein, J.S.

    1990-01-01

    This paper determines the accuracy of lateral chest radiography in the detection of masses in the inferior hilar window, a normally avascular hilar region anterior to the lower lobe bronchi. Fifty patients with normal thoracic CT scans and 25 with hilar masses/adenopathy were selected retrospectively. The 75 corresponding lateral chest radiographs were blindly evaluated for visibility of the anterior walls of the lower lobe bronchi and the presence and laterality of abnormal soft tissue (>1 cm) in the inferior hilar window. Only a 7 x 7-cm square of the lateral radiograph was viewed

  12. Strong adhesion of Saos-2 cells to multi-walled carbon nanotubes

    International Nuclear Information System (INIS)

    Matsuoka, Makoto; Akasaka, Tsukasa; Totsuka, Yasunori; Watari, Fumio

    2010-01-01

    In recent years, carbon nanotubes (CNTs) have been considered potential biomedical materials because of their unique character. The aim of this study was to investigate the response of a human osteoblast-like cell line - Saos-2 - on single-walled CNTs (SWCNTs) and multi-walled CNTs (MWCNTs). The surface of a culture dish was coated with CNTs, and Saos-2 cells were cultured for three days. Cell morphology, viability, alkaline phosphatase (ALP) activity, adhesion, and vinculin expression were evaluated. The result showed high cell viability and strong adhesion to MWCNTs. Saos-2 cultured on MWCNTs exhibited vinculin expression throughout the cell body, while the cells attached to SWCNTs and glass were mostly limited to their periphery. Our results suggest that CNT coatings promote cell activity and adhesiveness. These findings indicate that MWCNTs could be used as surface coating materials to promote cell adhesion.

  13. The effect of functionalization on structure and electrical conductivity of multi-walled carbon nanotubes

    International Nuclear Information System (INIS)

    Lau, Cher Hon; Cervini, Raoul; Clarke, Stephen R.; Markovic, Milena Ginic; Matisons, Janis G.; Hawkins, Stephen C.; Huynh, Chi P.; Simon, George P.

    2008-01-01

    Carbon nanotubes (CNTs) are of interest in many areas of nanotechnology and used in a number of novel applications. However effective dispersion remains a problem and one solution is to functionalize the nanotubes. Any functionalization that is undertaken must preferably not influence other key properties such as strength and electrical conductivity. In this work, multi-walled CNTs are functionalized for comparison, using a range of oxidative techniques, including thermal treatment, acid reflux, and dry UV-ozonolysis. The effects of these treatments on the multi-walled carbon nanotubes (MWCNTs) and their electrical properties were characterized using a range of surface and compositional techniques. The electrical conductivity of MWCNTs was found to increase with functionalization in all cases, and dry UV-ozonolysis was shown to be the treatment technique which best increased conductivity, whilst at the same time maintaining the structural integrity of the nanotubes, even though the level of modification was less than by the other treatment methods.

  14. Enhanced Imaging of Building Interior for Portable MIMO Through-the-wall Radar

    Science.gov (United States)

    Song, Yongping; Zhu, Jiahua; Hu, Jun; Jin, Tian; Zhou, Zhimin

    2018-01-01

    Portable multi-input multi-output (MIMO) radar system is able to imaging the building interior through aperture synthesis. However, significant grating lobes are invoked in the directly imaging results, which may deteriorate the imaging quality of other targets and influence the detail information extraction of imaging scene. In this paper, a two-stage coherence factor (CF) weighting method is proposed to enhance the imaging quality. After obtaining the sub-imaging results of each spatial sampling position using conventional CF approach, a window function is employed to calculate the proposed “enhanced CF” adaptive to the spatial variety effect behind the wall for the combination of these sub-images. The real data experiment illustrates the better performance of proposed method on grating lobes suppression and imaging quality enhancement compare to the traditional radar imaging approach.

  15. Comparison of 4-chloro-2-nitrophenol adsorption on single-walled and multi-walled carbon nanotubes

    Directory of Open Access Journals (Sweden)

    Mehrizad Ali

    2012-09-01

    Full Text Available Abstract The adsorption characteristics of 4-chloro-2-nitrophenol (4C2NP onto single-walled and multi-walled carbon nanotubes (SWCNTs and MWCNTs from aqueous solution were investigated with respect to the changes in the contact time, pH of solution, carbon nanotubes dosage and initial 4C2NP concentration. Experimental results showed that the adsorption efficiency of 4C2NP by carbon nanotubes (both of SWCNTs and MWCNTs increased with increasing the initial 4C2NP concentration. The maximum adsorption took place in the pH range of 2–6. The linear correlation coefficients of different isotherm models were obtained. Results revealed that the Langmuir isotherm fitted the experimental data better than the others and based on the Langmuir model equation, maximum adsorption capacity of 4C2NP onto SWCNTs and MWCNTs were 1.44 and 4.42 mg/g, respectively. The observed changes in the standard Gibbs free energy, standard enthalpy and standard entropy showed that the adsorption of 4C2NP onto SWCNTs and MWCNTs is spontaneous and exothermic in the temperature range of 298–328 K.

  16. The Interaction Features of the Multi-Level Retaining Walls with Soil Mass

    Directory of Open Access Journals (Sweden)

    Boyko Igor

    2017-09-01

    Full Text Available The interaction features of multi-level retaining walls with soil base were researched by changing their geometric parameters and locality at the plan. During excavation of deep foundation pits it is important to choose the type of constructions which influences on the horizontal displacements. The distance between the levels of retaining walls should be based on the results of numerical modelling. The objective of this paper is to present a comparison between the data of numerical simulations and the results of the in-situ lateral tests of couple piles. The problems have been solved by using the following soil models: Coulomb-Mohr model; model, which is based on the dilatation theory; elastic-plastic model with variable stiffness parameters.

  17. Freestanding bucky paper with high strength from multi-wall carbon nanotubes

    International Nuclear Information System (INIS)

    Li, Zhonglai; Xu, Ju; O'Byrne, Justin P.; Chen, Lan; Wang, Kaixue; Morris, Michael A.; Holmes, Justin D.

    2012-01-01

    Bucky papers have been investigated by some research groups, however, due to different qualities of carbon nanotubes used, various results of strength and electronic properties were reported in the literatures. In this article, the effects of carbon nanotubes synthesized over different catalysts on the qualities of bucky papers were systemically investigated. Multi-wall carbon nanotubes were synthesized over a series of MgO supported catalysts with different weight ratios of Mo and Co. As the ratios of Mo/Co in the catalysts were increased from 0 to 3, the yields of carbon nanotubes were enhanced from 7 wt% to 400 wt%. However, the yield enhancement of carbon nanotubes was achieved at the expense of higher proportion of structural defects within carbon nanotubes, which has been proved by Raman spectroscopy and thermogravimetry analysis. It was demonstrated that the tensile strength of bucky paper composed of numerous MCNTs bundles strongly depends on the structure of carbon nanotubes used. By optimizing reaction conditions, a bucky paper with high strain up to 15.36 MPa and electrical conductivity of 61.17 S cm −1 was obtained by Supercritical Fluid (SCF) drying technique. -- Highlights: ► Multi-wall carbon nanotube bucky paper. ► Structural defects of carbon nanotubes. ► CoMo catalyst. ► Tensile strength of bucky paper.

  18. High-Power Ka-Band Window and Resonant Ring

    International Nuclear Information System (INIS)

    Jay L. Hirshfield

    2006-01-01

    A stand-alone 200 MW rf test station is needed for carrying out development of accelerator structures and components for a future high-gradient multi-TeV collider, such as CLIC. A high-power rf window is needed to isolate the test station from a structure element under test. This project aimed to develop such a window for use at a frequency in the range 30-35 GHz, and to also develop a high-power resonant ring for testing the window. During Phase I, successful conceptual designs were completed for the window and the resonant ring, and cold tests of each were carried out that confirmed the designs

  19. Prospects for using multi-walled carbon nanotubes formed from renewable feedstock in hydrogen energy

    International Nuclear Information System (INIS)

    Onishchenko, D. V.

    2013-01-01

    Mechanoactivation of amorphous carbon synthesized from renewable feedstock promotes formation of multi-walled carbon nanotubes, and the best results were obtained using the feedstock of sphagnum moss. It is shown that the carbon nanotubes formed from different plant feedstock have a high sorption capacity with respect to hydrogen. (author)

  20. Ferromagnetic behaviour of polyaniline-coated multi-wall carbon nanotubes containing nickel nanoparticles

    Czech Academy of Sciences Publication Activity Database

    Konyushenko, Elena; Kazantseva, N. E.; Stejskal, Jaroslav; Trchová, Miroslava; Kovářová, Jana; Sapurina, I.; Tomishko, M. M.

    2008-01-01

    Roč. 320, 3-4 (2008), s. 231-240 ISSN 0304-8853 R&D Projects: GA AV ČR IAA4050313; GA AV ČR IAA400500504; GA MŠk ME 847; GA ČR GA202/06/0419 Institutional research plan: CEZ:AV0Z40500505 Keywords : multi-wall carbon nanotube * conducting polymer * polyaniline coating Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.283, year: 2008

  1. Equilibrium and Thermodynamic Studies of Methane Adsorption on Multi-Walled Carbon Nanotube

    OpenAIRE

    Sanaz. Monemtabary; Mojtaba Shariati Niasar; Mohsen Jahanshahi; Ali Asghar Ghoreyshi

    2013-01-01

    In this work, The adsorption of methane onto multi-walled carbon nanotubes (MWCNTs) was studied, in which the influences of temperatureand pressure were investigated. The physical properties of the MWCNT were systematically characterised by Scanning Electron Microscopy (SEM) and Brunauere-Emmette-Teller (BET) surface area measurements. The equilibrium adsorption data were analyzed using threecommon adsorption models: Langmuir, Freundlich and Sips. All of the models fit the experimental result...

  2. An Approach for Patient-Specific Multi-domain Vascular Mesh Generation Featuring Spatially Varying Wall Thickness Modeling

    OpenAIRE

    Raut, Samarth S.; Liu, Peng; Finol, Ender A.

    2015-01-01

    In this work, we present a computationally efficient image-derived volume mesh generation approach for vasculatures that implements spatially varying patient-specific wall thickness with a novel inward extrusion of the wall surface mesh. Multi-domain vascular meshes with arbitrary numbers, locations, and patterns of both iliac bifurcations and thrombi can be obtained without the need to specify features or landmark points as input. In addition, the mesh output is coordinate-frame independent ...

  3. Multi-scale full-field measurements and near-wall modeling of turbulent subcooled boiling flow using innovative experimental techniques

    Energy Technology Data Exchange (ETDEWEB)

    Hassan, Yassin A., E-mail: y-hassan@tamu.edu

    2016-04-01

    Highlights: • Near wall full-field velocity components under subcooled boiling were measured. • Simultaneous shadowgraphy, infrared thermometry wall temperature and particle-tracking velocimetry techniques were combined. • Near wall velocity modifications under subcooling boiling were observed. - Abstract: Multi-phase flows are one of the challenges on which the CFD simulation community has been working extensively with a relatively low success. The phenomena associated behind the momentum and heat transfer mechanisms associated to multi-phase flows are highly complex requiring resolving simultaneously for multiple scales on time and space. Part of the reasons behind the low predictive capability of CFD when studying multi-phase flows, is the scarcity of CFD-grade experimental data for validation. The complexity of the phenomena and its sensitivity to small sources of perturbations makes its measurements a difficult task. Non-intrusive and innovative measuring techniques are required to accurately measure multi-phase flow parameters while at the same time satisfying the high resolution required to validate CFD simulations. In this context, this work explores the feasible implementation of innovative measuring techniques that can provide whole-field and multi-scale measurements of two-phase flow turbulence, heat transfer, and boiling parameters. To this end, three visualization techniques are simultaneously implemented to study subcooled boiling flow through a vertical rectangular channel with a single heated wall. These techniques are listed next and are used as follow: (1) High-speed infrared thermometry (IR-T) is used to study the impact of the boiling level on the heat transfer coefficients at the heated wall, (2) Particle Tracking Velocimetry (PTV) is used to analyze the influence that boiling parameters have on the liquid phase turbulence statistics, (3) High-speed shadowgraphy with LED illumination is used to obtain the gas phase dynamics. To account

  4. Characterization of mechanical properties of hydroxyapatite-silicon-multi walled carbon nano tubes composite coatings synthesized by EPD on NiTi alloys for biomedical application.

    Science.gov (United States)

    Khalili, Vida; Khalil-Allafi, Jafar; Sengstock, Christina; Motemani, Yahya; Paulsen, Alexander; Frenzel, Jan; Eggeler, Gunther; Köller, Manfred

    2016-06-01

    Release of Ni(1+) ions from NiTi alloy into tissue environment, biological response on the surface of NiTi and the allergic reaction of atopic people towards Ni are challengeable issues for biomedical application. In this study, composite coatings of hydroxyapatite-silicon multi walled carbon nano-tubes with 20wt% Silicon and 1wt% multi walled carbon nano-tubes of HA were deposited on a NiTi substrate using electrophoretic methods. The SEM images of coated samples exhibit a continuous and compact morphology for hydroxyapatite-silicon and hydroxyapatite-silicon-multi walled carbon nano-tubes coatings. Nano-indentation analysis on different locations of coatings represents the highest elastic modulus (45.8GPa) for HA-Si-MWCNTs which is between the elastic modulus of NiTi substrate (66.5GPa) and bone tissue (≈30GPa). This results in decrease of stress gradient on coating-substrate-bone interfaces during performance. The results of nano-scratch analysis show the highest critical distance of delamination (2.5mm) and normal load before failure (837mN) as well as highest critical contact pressure for hydroxyapatite-silicon-multi walled carbon nano-tubes coating. The cell culture results show that human mesenchymal stem cells are able to adhere and proliferate on the pure hydroxyapatite and composite coatings. The presence of both silicon and multi walled carbon nano-tubes (CS3) in the hydroxyapatite coating induce more adherence of viable human mesenchymal stem cells in contrast to the HA coated samples with only silicon (CS2). These results make hydroxyapatite-silicon-multi walled carbon nano-tubes a promising composite coating for future bone implant application. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Electrical conductivity of compacts of graphene, multi-wall carbon nanotubes, carbon black, and graphite powder

    NARCIS (Netherlands)

    Marinho, B.; Gomes Ghislandi, M.; Tkalya, E.; Koning, C.E.; With, de G.

    2012-01-01

    The electrical conductivity of different carbon materials (multi-walled carbon nanotubes, graphene, carbon black and graphite), widely used as fillers in polymeric matrices, was studied using compacts produced by a paper preparation process and by powder compression. Powder pressing assays show that

  6. Development of a prototype fresh-air window to be used in combination with off-air systems, especially for modernisation of multistorey apartment buildings; Entwicklung des Prototypes eines Zuluftfensters fuer den Einsatz in Verbindung mit Abluftanlagen, insbesondere bei der Sanierung von mehrgeschossigen Mietwohngebaeuden

    Energy Technology Data Exchange (ETDEWEB)

    Gronau, H.J.; Helbig, S. [Weimar Univ. (Germany). Materialforschungs- und Pruefanstalt

    1997-12-31

    Off-air systems depend on whether there is a sufficient supply of fresh air. This research project aims to develop a prototype of a fresh-air element in the form of a three-pane composite window. The state of progress, results of the numerical studies, and problems encountered are reported. (MSK) [Deutsch] Da Abluftanlagen von einer hinreichend gesicherten Zuluftversorgung abhaengig sind, ist es das Ziel dieses Forschungsvorhabens, den Prototyp eines Zuluftelements in Form eines 3-Scheiben-Verbundfensters zu entwickeln. Im Folgenden werden der Stand der Arbeiten, die Ergebnisse der numerischen Untersuchungen sowie auftretende Probleme erlaeutert.

  7. Windowing UWB microwave, mm-wave multi-port S-parameter measurements using open-ended excess electrical length

    Directory of Open Access Journals (Sweden)

    Gholamreza Askari

    2017-05-01

    Full Text Available Multi-port measurements are a big challenge in circuits' verification, especially when the frequency increases. This study presents a new technique for measuring S-parameters of multi-port ultra-wideband (UWB microwave and mm-wave circuits. The concepts are based on direct or indirect applying modulated UWB impulse radio in desired bandwidth to the one port of the modified multi-port circuit and gathering the reflected signal in the same port and the output signal in the second port in time domain, and the other ports are left opened with a special designed added electrical length. Then by applying intelligent windowing in time domain to the gathering data, and using fast Fourier transform, the desired S-parameters are extracted. Validation of this technique is verified by design and fabrication of a three-port UWB Wilkinson power divider in 22–30 GHz. The simulation and measurement results of the reflection and transmission S-parameters by using this new technique are very close to those are extracted with the conventional vector network analysers S-parameters measurements and show the ability and the accuracy of this technique.

  8. Limited transport of functionalized multi-walled carbon nanotubes in two natural soils

    International Nuclear Information System (INIS)

    Kasel, Daniela; Bradford, Scott A.; Šimůnek, Jiří; Pütz, Thomas; Vereecken, Harry; Klumpp, Erwin

    2013-01-01

    Column experiments were conducted in undisturbed and in repacked soil columns at water contents close to saturation (85–96%) to investigate the transport and retention of functionalized 14 C-labeled multi-walled carbon nanotubes (MWCNT) in two natural soils. Additionally, a field lysimeter experiment was performed to provide long-term information at a larger scale. In all experiments, no breakthrough of MWCNTs was detectable and more than 85% of the applied radioactivity was recovered in the soil profiles. The retention profiles exhibited a hyper-exponential shape with greater retention near the column or lysimeter inlet and were successfully simulated using a numerical model that accounted for depth-dependent retention. In conclusion, results indicated that the soils acted as a strong sink for MWCNTs. Little transport of MWCNTs is therefore likely to occur in the vadose zone, and this implies limited potential for groundwater contamination in the investigated soils. -- Highlights: •Investigation of undisturbed soil columns and lysimeter. •Transport experiments under water-unsaturated conditions. •Retention profiles were measured and numerically modeled. •Complete retention of MWCNT in undisturbed and repacked soil columns. -- In undisturbed columns and a lysimeter study, complete retention of functionalized multi-walled carbon nanotubes was found in two soils at environmentally relevant conditions

  9. A numerical study of the effect of vent flow angle on the heat transfer rate from a cold window with a below-window hot-air vent

    Energy Technology Data Exchange (ETDEWEB)

    Oosthuizen, P.H. [Queen' s Univ., Kingston, ON (Canada). Dept. of Mechanical and Materials Engineering

    2010-07-01

    This study investigated the effects of the discharge angle on air leaving a hot air vent mounted below a window. The window was represented by a plane isothermal section recessed into a wall and was colder than air in the rest of the room. The vent was placed against the wall and had a uniform discharge velocity. Flow was assumed to be steady. Both laminar and turbulent flows were evaluated using a commercial computational fluid dynamics (CFD) simulation tool. A k-epsilon turbulence model was used to determine turbulent flow calculations. The study determined the Rayleigh number based on window height, the Reynolds number based on the vent discharge velocity, the angle of the vent discharge flow, the Prandtl number, and dimensionless vent discharge temperature differences. The study showed that a relatively thin layer of cold air adjacent to the floor is present at high Rayleigh numbers, where the downward natural convective flow over the window dominates the overall flow. At low Rayleigh numbers, the cold air flows upward towards the ceiling and temperatures in the room are nearly uniform. 47 refs., 11 figs.

  10. Understanding Windows | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  11. Determination of multi-walled carbon nanotube bioaccumulation in earthworms measured by a microwave-based detection technique

    Science.gov (United States)

    Reliable quantification techniques for carbon nanotubes (CNTs) are limited. In this study, a new procedure was developed for quantifying multi-walled carbon nanotubes (MWNTs) in earthworms (Eisenia fetida) based on freeze drying and microwave-induced heating. Specifically, earthw...

  12. Interlaminar Fracture Toughness of CFRP Laminates Incorporating Multi-Walled Carbon Nanotubes

    Directory of Open Access Journals (Sweden)

    Elisa Borowski

    2015-06-01

    Full Text Available Carbon fiber reinforced polymer (CFRP laminates exhibit limited fracture toughness due to characteristic interlaminar fiber-matrix cracking and delamination. In this article, we demonstrate that the fracture toughness of CFRP laminates can be improved by the addition of multi-walled carbon nanotubes (MWCNTs. Experimental investigations and numerical modeling were performed to determine the effects of using MWCNTs in CFRP laminates. The CFRP specimens were produced using an epoxy nanocomposite matrix reinforced with carboxyl functionalized multi-walled carbon nanotubes (COOH–MWCNTs. Four MWCNTs contents of 0.0%, 0.5%, 1.0%, and 1.5% per weight of the epoxy resin/hardener mixture were examined. Double cantilever beam (DCB tests were performed to determine the mode I interlaminar fracture toughness of the unidirectional CFRP composites. This composite material property was quantified using the critical energy release rate, GIC. The experimental results show a 25%, 20%, and 17% increase in the maximum interlaminar fracture toughness of the CFRP composites with the addition of 0.5, 1.0, and 1.5 wt% MWCNTs, respectively. Microstructural investigations using Fourier transform infrared (FTIR spectroscopy and X-ray photoelectron spectroscopy (XPS verify that chemical reactions took place between the COOH–MWCNTs and the epoxy resin, supporting the improvements experimentally observed in the interlaminar fracture toughness of the CFRP specimens containing MWCNTs. Finite element (FE simulations show good agreement with the experimental results and confirm the significant effect of MWCNTs on the interlaminar fracture toughness of CFRP.

  13. Preparation of graphene oxide/polypyrrole/multi-walled carbon nanotube composite and its application in supercapacitors

    International Nuclear Information System (INIS)

    Wang, Bin; Qiu, Jianhui; Feng, Huixia; Sakai, Eiichi

    2015-01-01

    Highlights: • A novel method for synthesizing graphene oxide/polypyrrole/multi-walled nanotube composites. • Investigation of the effects of the mass ratio of GO, CM and Py on the capacitance of prepared composites. • Excellent electrochemical performance of PCMG composites. - Abstract: We report a novel method for preparing graphene oxide/polypyrrole/multi-walled carbon nanotubes (MWCNTs) composites (PCMG). The MWCNTs are treated by sulfuric acid, nitric acid and thionyl chloride, and then composite with graphene oxide and PPy by in suit polymerization. Transition electron microscopy (TEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) results show that in 3-D structure of PCMG composites, PPy chains act as the “bridge” between graphene oxide and chlorinated-MWCNTs. Electrochemical tests reveal that the PCMG1-1 composite has high capacitance of 406.7 F g −1 at current density of 0.5 A g −1 , and the capacitance retention of PCMG1-1 composite is 92% after 1000 cycles

  14. Fabrication and mechanical properties of multi-walled carbon nanotubes/epoxy nanocomposites

    International Nuclear Information System (INIS)

    Yeh, M.-K.; Hsieh, T.-H.; Tai, N.-H.

    2008-01-01

    Carbon nanotubes have better physical and mechanical behavior than the traditional materials. In this study, the multi-walled carbon nanotubes (MWNTs) were added to the epoxy resin as a reinforcement to fabricate MWNTs/epoxy nanocomposites. The pressure and temperature were applied to cure the MWNTs/epoxy compound by hot press method. Mechanical properties such as tensile strength, Young's modulus, and Poisson's ratio were measured. The effect of weight percentages of the MWNTs was investigated. Morphologies of the fracture surface of MWNTs/epoxy nanocomposites were observed by scanning electron microscope

  15. Implication of multi-walled carbon nanotubes on polymer/graphene composites

    International Nuclear Information System (INIS)

    Araby, Sherif; Saber, Nasser; Ma, Xing; Kawashima, Nobuyuki; Kang, Hailan; Shen, Heng; Zhang, Liqun; Xu, Jian; Majewski, Peter; Ma, Jun

    2015-01-01

    Highlights: • Influence of adding carbon nanotubes (CNTs) into elastomer/graphene composites. • Multi-walled CNTs work supplementally to GnPs by forming conductive networks. • The findings illuminate marked synergistic effect between MWCNTs and graphene sheets. - Abstract: Graphene sheets stack in polymer matrices while multi-walled carbon nanotubes (MWCNTs) entangle themselves, forming two daunting challenges in the design and fabrication of polymer composites. Both challenges have been simultaneously addressed in this study by hybridizing the two nanomaterials through melt compounding to develop elastomer/graphene platelet/MWCNT (3-phase) composites, where MWCNTs were fixed at 2.8 vol% (5 wt%) for all fractions. We investigated the composites’ structure and properties, and compared the 3-phase composites with elastomer/graphene platelet (2-phase) composites. MWCNTs may bridge graphene platelets (GnPs) and promote their dispersion in the matrix, which would provide more interface area between the matrix and the fillers. MWCNTs worked supplementally to GnPs by forming conductive networks, where MWCNTs acted as long nanocables to transport electrons and stress while GnPs served as interconnection sites between the tubes forming local conductive paths. This produced a percolation threshold of electrical conductivity at 2.3 vol% for 3-phase composites, 88% lower than that of 2-phase composites. At 26.7 vol% of total filler content (MWCNTs + GnPs), tensile strength, Young’s modulus and tear strength showed respectively 303%, 115%, 155% further improvements over those of 2-phase composites. These improvements are originated from the synergistic effect between GnPs and MWCNTs. The conducting elastomeric composites developed would potentially open the door for applications in automotive and aerospace industries

  16. Positron annihilation characteristics in multi-wall carbon nanotubes with different average diameters

    International Nuclear Information System (INIS)

    Tuyen, L A; Khiem, D D; Phuc, P T; Kajcsos, Zs; Lázár, K; Tap, T D

    2013-01-01

    Positron lifetime spectroscopy was used to study multi-wall carbon nanotubes. The measurements were performed in vacuum on the samples having different average diameters. The positron lifetime values depend on the nanotube diameter. The results also show an influence of the nanotube diameter on the positron annihilation intensity on the nanotube surface. The change in the annihilation probability is described and interpreted by the modified diffusion model introducing the positron escape rate from the nanotubes to their external surface.

  17. In vitro evaluation of osteoblastic cells on bacterial cellulose modified with multi-walled carbon nanotubes as scaffold for bone regeneration

    Energy Technology Data Exchange (ETDEWEB)

    Gutiérrez-Hernández, José Manuel [Coordination for Innovation and Application of Science and Technology, Autonomous University San Luis Potosi, 78000 San Luis Potosi (Mexico); Department of Wood, Cellulose and Paper Research, University Guadalajara, 45110 Guadalajara (Mexico); Escobar-García, Diana María [Laboratory of Basic Sciences, Faculty of Dentistry, Autonomous University San Luis Potosi, 78000 San Luis Potosi (Mexico); Escalante, Alfredo [Department of Wood, Cellulose and Paper Research, University Guadalajara, 45110 Guadalajara (Mexico); Flores, Hector [Laboratory of Basic Sciences, Faculty of Dentistry, Autonomous University San Luis Potosi, 78000 San Luis Potosi (Mexico); González, Francisco Javier [Coordination for Innovation and Application of Science and Technology, Autonomous University San Luis Potosi, 78000 San Luis Potosi (Mexico); Gatenholm, Paul [Chalmers University of Technology, Department of Chemistry and Chemical Engineering, Biopolymer Technology, SE-412 96 Göteborg (Sweden); Toriz, Guillermo, E-mail: gtoriz@dmcyp.cucei.udg.mx [Department of Wood, Cellulose and Paper Research, University Guadalajara, 45110 Guadalajara (Mexico); Chalmers University of Technology, Department of Chemistry and Chemical Engineering, Biopolymer Technology, SE-412 96 Göteborg (Sweden)

    2017-06-01

    In this paper we explore the use of native bacterial cellulose (BC) in combination with functionalized multi-walled carbon nanotubes (MWNTs) as an original biomaterial, suitable three-dimensional (3D) scaffold for osteoblastic cell culture. Functionalized MWNTs were mixed with native BC (secreted by Gluconacetobacter xylinus) with the aim of reinforcing the mechanical properties of BC. The results indicate that BC-MWNTs scaffolds support osteoblast viability, adhesion and proliferation at higher levels as compared to traditional culture substrates. Chemically functionalized MWNTs are also an excellent material to be used as scaffold because these did not affect cell viability and showed an enhanced osteoblast adhesion. These results suggest the potential for this combination of biomaterials, i.e. BC and carbon nanomaterials, as scaffolds for bone regeneration. - Highlights: • Functionalization of multiwalled carbon nanotubes with carboxyl groups for reduces their toxicity against osteoblastic cells. • Use of native bacterial cellulose with functionalized multi-walled carbon nanotubes as scaffolds for tissue engineering. • Bacterial cellulose with multi-walled carbon nanotubes as scaffolds give an excellent option to be used in bone regeneration.

  18. In vitro evaluation of osteoblastic cells on bacterial cellulose modified with multi-walled carbon nanotubes as scaffold for bone regeneration

    International Nuclear Information System (INIS)

    Gutiérrez-Hernández, José Manuel; Escobar-García, Diana María; Escalante, Alfredo; Flores, Hector; González, Francisco Javier; Gatenholm, Paul; Toriz, Guillermo

    2017-01-01

    In this paper we explore the use of native bacterial cellulose (BC) in combination with functionalized multi-walled carbon nanotubes (MWNTs) as an original biomaterial, suitable three-dimensional (3D) scaffold for osteoblastic cell culture. Functionalized MWNTs were mixed with native BC (secreted by Gluconacetobacter xylinus) with the aim of reinforcing the mechanical properties of BC. The results indicate that BC-MWNTs scaffolds support osteoblast viability, adhesion and proliferation at higher levels as compared to traditional culture substrates. Chemically functionalized MWNTs are also an excellent material to be used as scaffold because these did not affect cell viability and showed an enhanced osteoblast adhesion. These results suggest the potential for this combination of biomaterials, i.e. BC and carbon nanomaterials, as scaffolds for bone regeneration. - Highlights: • Functionalization of multiwalled carbon nanotubes with carboxyl groups for reduces their toxicity against osteoblastic cells. • Use of native bacterial cellulose with functionalized multi-walled carbon nanotubes as scaffolds for tissue engineering. • Bacterial cellulose with multi-walled carbon nanotubes as scaffolds give an excellent option to be used in bone regeneration.

  19. Modeling and Solving the Multi-depot Vehicle Routing Problem with Time Window by Considering the Flexible end Depot in Each Route

    Directory of Open Access Journals (Sweden)

    Mohammad Mirabi

    2016-11-01

    Full Text Available This paper considers the multi-depot vehicle routing problem with time window in which each vehicle starts from a depot and there is no need to return to its primary depot after serving customers. The mathematical model which is developed by new approach aims to minimizing the transportation cost including the travelled distance, the latest and the earliest arrival time penalties. Furthermore, in order to reduce the problem searching space, a novel GA clustering method is developed. Finally, Experiments are run on number problems of varying depots and time window, and customer sizes. The method is compared to two other clustering techniques, fuzzy C means (FCM and K-means algorithm. Experimental results show the robustness and effectiveness of the proposed algorithm.

  20. Nanocomposites of nitrile (NBR) rubber with multi-walled carbon nanotubes

    Science.gov (United States)

    Warasitthinon, Nuthathai

    Nanotechnology offers the promise of creating new materials with enhanced performance. There are different kinds of fillers used in rubber nanocomposites, such as carbon black, silica, carbon fibers, and organoclays. Carbon nanotube reinforced elastomers have potential for improved rubber properties in aggressive environments. The first chapter is an introduction to the literature. The second chapter investigated the incorporation of multi-walled carbon nanotubes (MWCNTs) into rubber matrix for potential use in high temperature applications. The vulcanization kinetics of acrylonitrile butadiene rubber (NBR) reinforced with multi-walled carbon nanotubes was investigated. The vulcanized NBR rubber with different loading percentages of MWCNTs was also compared to NBR reinforced with carbon black N330. The optimum curing time at 170°C (T90) was found to decrease with increasing content of MWCNTs. Increased filler loading of both carbon black and MWCNTs gave higher modulus and strength. The MWCNTs filled materials gave better retention of modulus and tensile strength at high temperatures, but lower strength as compared to the carbon black filled samples. In the third chapter, carbon black (CB, 50phr) content in nitrile rubber (NBR) nanocomposites was partially replaced by multi-walled carbon nanotubes (MWCNTs). NBR/CB/CNTs nanocomposites with varying ratio of CB/CNTs (50/0 phr to 40/10 phr) were formulated via the melt-mixing method using an internal mixer. The reinforcing effect of single filler (CB) and mixture of fillers (CB and CNTs) on the properties of NBR nanocomposites was investigated. The cure kinetics and bound rubber content were analyzed using rheometry and solvent swelling method. In addition, mechanical behavior at both room temperature and high temperature (350°F/ 121°C) were examined. The scorch time and curing time values showed that there was no significant effect on the curing behavior of NBR nanocomposites after the partial replacement of CB with

  1. 16-slice multi-detector row CT coronary angiography: image quality and optimization of the image reconstruction window

    International Nuclear Information System (INIS)

    Kim, Yoo Kyung; Shim, Sung Shine; Lim, Soo Mee; Hwang, Ji Young; Kim, Yoon Kyung

    2005-01-01

    The purpose of this experiment is to investigate the image quality of CT coronary angiography using a 16-slice multi-detector row CT and to determine the optimal image reconstruction window. CT coronary angiography was obtained in 36 nonsymptomatic volunteers using a 16-slice multi-detector row CT (SOMATOM Sensation, Siemens Medical System). The mean heart rates were 70 beats per minute (bpm) or less in 18 persons and more than 70 bpm in 18 persons. Eleven data sets were obtained for each patient (reconstructed at 30%-80% of the cardiac cycle with an increment of 5%). Image quality of the eight coronary segments [left main coronary artery (LM), proximal and middle segments of left anterior descending artery (p-LAD, m-LAN) and left circumflex coronary artery (p-LCx, m-LCx) and proximal, middle and distal segments of right coronary artery (p-RCA, m-RCA, d-RCA)] was assessed. The optimal reconstruction windows in the cardiac cycle for the best image quality were 60-70% for the segments of the LM, LAD, and LC arteries in two groups (bpm 70) and 55-65% (bpm 70) for the segments of the RCA. On the best dataset for each coronary segment, the following diagnostic image quality was achieved in the two groups: LM: 100%, 83%; p-LAD: 100%, 88% m-LAD: 100%, 72%; p-LCx: 100%, 72%; m-LCx: 100%, 72%; p-RCA: 94%, 72%; m-RCA: 61%, 50%; d-RCA: 100%, 80%. The 16 slice multi-detector row CT scan provided visualization of the coronary arteries with high resolution. Especially in the group with a mean heart rate of 70 bpm or less, all the coronary segments except the RCA showed diagnostic image quality. Optimal image quality was achieved with a 60-70% trigger delay for all coronary arterial segments, but the best images of RCA were achieved in the earlier cardiac phase in the patients with a mean heart rate of more than 70 bpm

  2. Proper orthogonal decomposition-based estimations of the flow field from particle image velocimetry wall-gradient measurements in the backward-facing step flow

    International Nuclear Information System (INIS)

    Nguyen, Thien Duy; Wells, John Craig; Mokhasi, Paritosh; Rempfer, Dietmar

    2010-01-01

    In this paper, particle image velocimetry (PIV) results from the recirculation zone of a backward-facing step flow, of which the Reynolds number is 2800 based on bulk velocity upstream of the step and step height (h = 16.5 mm), are used to demonstrate the capability of proper orthogonal decomposition (POD)-based measurement models. Three-component PIV velocity fields are decomposed by POD into a set of spatial basis functions and a set of temporal coefficients. The measurement models are built to relate the low-order POD coefficients, determined from an ensemble of 1050 PIV fields by the 'snapshot' method, to the time-resolved wall gradients, measured by a near-wall measurement technique called stereo interfacial PIV. These models are evaluated in terms of reconstruction and prediction of the low-order temporal POD coefficients of the velocity fields. In order to determine the estimation coefficients of the measurement models, linear stochastic estimation (LSE), quadratic stochastic estimation (QSE), principal component regression (PCR) and kernel ridge regression (KRR) are applied. We denote such approaches as LSE-POD, QSE-POD, PCR-POD and KRR-POD. In addition to comparing the accuracy of measurement models, we introduce multi-time POD-based estimations in which past and future information of the wall-gradient events is used separately or combined. The results show that the multi-time estimation approaches can improve the prediction process. Among these approaches, the proposed multi-time KRR-POD estimation with an optimized window of past wall-gradient information yields the best prediction. Such a multi-time KRR-POD approach offers a useful tool for real-time flow estimation of the velocity field based on wall-gradient data

  3. FABRICATION OF WINDOW SADDLES FOR NIF CRYOGENIC HOHLRAUMS

    International Nuclear Information System (INIS)

    GIRALDEZ, E; KAAE, J.L

    2003-09-01

    OAK-B135 A planar diagnostic viewing port attached to the cylindrical wall of the NIF cryogenic hohlraum requires a saddle-like transition piece. While the basic design of this window saddle is straightforward, its fabrication is not, given the scale and precision of the component. They solved the problem through the use of a two segment copper mandrel to electroform the gold window saddle. The segments were micro-machined using a combination of single-point diamond turning and single point diamond milling. These processes as well as the electroplating conditions, final machining and mandrel removal are described in this paper

  4. Fabrication of antibacterial PVA nanocomposite films containing dendritic polymer functionalized multi-walled carbon nanotubes

    Science.gov (United States)

    Sapalidis, Andreas; Sideratou, Zili; Panagiotaki, Katerina N.; Sakellis, Elias; Kouvelos, Evangelos P.; Papageorgiou, Sergios; Katsaros, Fotios

    2018-03-01

    A series of Poly(vinyl alcohol) (PVA) nanocomposite films containing quaternized hyperbranched polyethyleneimine (PEI) functionalized multi-walled carbon nanotubes (ox-CNTs@QPEI) are prepared by solvent casting technique. The modified carbon based material exhibits high aqueous solubility, due to the hydrophilic character of the functionalized hyperbranched dendritic polymer. The quaternized PEI successfully wraps around nanotube walls, as polycations provide electrostatic repulsion. Various contents of ox-CNTs@QPEI ranging from 0.05 to 1.0 % w/w were employed to prepare functionalized PVA nanocomposites. The developed films exhibit adequate optical transparency, improved mechanical properties and extremely high antibacterial behavior due to the excellent dispersion of the functionalized carbon nanotubes into the PVA matrix.

  5. Window Glazing Types | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  6. Window Frame Types | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  7. Window Operator Types | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  8. Mild hydrothermal treatment to prepare highly dispersed multi-walled carbon nanotubes

    International Nuclear Information System (INIS)

    Zhang Li; Hashimoto, Yoshio; Taishi, Toshinori; Ni Qingqing

    2011-01-01

    Multi-walled carbon nanotubes (MWCNTs) with improved dispersion property have been prepared by a mild and fast hydrothermal treatment. The hydrothermal process avoids using harsh oxidants and organic solvents, which is environmental friendly and greatly decreases the damage to intrinsic structure of MWCNTs. The modified MWCNTs were highly soluble in polar solvents such as water, ethanol and dimethylformamide. Morphological observation by TEM indicated that the diameter and inherent structure were well reserved in modified MWCNTs. X-ray photoelectron spectroscopy and Raman spectroscopy were used to quantify functional groups created on the MWCNT surface, and to determine rational parameters of hydrothermal process.

  9. Feasibility of multi-walled carbon nanotube probes in AFM anodization lithography

    International Nuclear Information System (INIS)

    Choi, Ji Sun; Bae, Sukjong; Ahn, Sang Jung; Kim, Dal Hyun; Jung, Ki Young; Han, Cheolsu; Chung, Chung Choo; Lee, Haiwon

    2007-01-01

    Multi-walled carbon nanotube (CNT) tips were used in atomic force microscope (AFM) anodization lithography to investigate their advantages over conventional tips. The CNT tip required a larger threshold voltage than the mother silicon tip due to the Schottky barrier at the CNT-Si interface. Current-to-voltage curves distinguished the junction property between CNTs and mother tips. The CNT-platinum tip, which is more conductive than the CNT-silicon tip, showed promising results for AFM anodization lithography. Finally, the nanostructures with high aspect ratio were fabricated using a pulsed bias voltage technique as well as the CNT tip

  10. Holistic energy retrofitting of multi-storey building to low energy level

    DEFF Research Database (Denmark)

    Morelli, Martin; Tommerup, Henrik M.; Tafdrup, Morten K.

    2011-01-01

    a holistic energy retrofitting of a multi-storey building from 1930 with facades worth preserving. Different single measures, e.g. windows and wall insulation, are assessed with regard to energy saving and economy. The best performing single measures are combined in a holistic retrofitting. The total energy...... consumption of the holistic solution is theoretically calculated, and the economy is documented based on calculations of cost of conserved energy. The results show that many single measures are cost-effective. However, when they are combined, the holistic retrofitting solution turns out not to be cost...

  11. Technical support document for proposed 1994 revision of the MEC thermal envelope requirements

    Energy Technology Data Exchange (ETDEWEB)

    Conner, C.C.; Lucas, R.G.

    1994-03-01

    This report documents the development of the proposed revision of the Council of American Building Officials` (CABO) 1994 supplement to the 1993 Model Energy Code (MEC) building thermal envelope requirements for maximum component U{sub 0}-value. The 1994 amendments to the 1993 MEC were established in last year`s code change cycle and did not change the envelope requirements. The research underlying the proposed MEC revision was conducted by Pacific Northwest Laboratory (PNL) for the US Department of Energy (DOE) Building Energy Standards program. The goal of this research was to develop revised guidelines based on an objective methodology that determines the most cost-effective (least total cost) combination of energy conservation measures (ECMs) (insulation levels and window types) for residential buildings. This least-cost set of ECMs was used as a basis for proposing revised MEC maximum U{sub 0}-values (thermal transmittances). ECMs include window types (for example, double-pane vinyl) and insulation levels (for example, R-19) for ceilings, walls, and floors.

  12. A continuous wave RF vacuum window

    International Nuclear Information System (INIS)

    Walton, R.

    1999-09-01

    An essential part of an ICRF system to be used in fusion reactor is the RF window. This is fitted in a coaxial transmission line. It forms a vacuum and tritium boundary between the antenna, situated inside the machine, and the transmission line, which feeds it. A double window is required with a vacuum inter-space. The dielectric, which forms the vacuum boundary, must be brazed into its housing. The window must be of a robust construction, and capable of withstanding both axial and radial loads. The vacuum boundaries should be thick walled in order act as a suitable tritium barrier. A further requirement is that the window is capable of continuous operation. The design of such a window is presented below. A half scale prototype has been manufactured, which has successfully completed RF, vacuum, and mechanical testing at JET, but has no water cooling, which is a requirement for continuous operation. The design presented here is for a window to match the existing 30 Ω main transmission lines at JET. It employs two opposed ceramic dielectric cones with a much increased angle of incidence compared with existing JET windows. The housing is machined from titanium. Small corona rings are used, and the tracking distance along the ceramic surface is large. The geometry minimizes the peak electric field strength. The design uses substantial pre-stressing during manufacture, to produce a compressive stress field throughout the dielectric material. Significant tensile stresses in the ceramic, and therefore the possibility of fracture due to applied thermal and mechanical loading, are eliminated in this way. A full-scale actively cooled RF window using this basic design should be capable of continuous use at 50 kV in the 20 - 90 MHz range. A half scale, inertially cooled prototype window has been designed, built and tested successfully at JET to 48 kV for up to 20 seconds. The prototype uses alumina for the dielectric, whereas beryllia is more appropriate for continuous

  13. Spectroscopic investigations on oxidized multi-walled carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Anandhi, C. M. S.; Premkumar, S.; Asath, R. Mohamed; Mathavan, T.; Benial, A. Milton Franklin, E-mail: miltonfranklin@yahoo.com [Department of Physics, N.M.S.S.V.N. College, Madurai-625 019, Tamil Nadu (India)

    2016-05-06

    The pristine multi-walled carbon nanotubes (MWCNTs) were oxidized by the ultrasonication process. The oxidized MWCNTs were characterized by the X-ray diffraction (XRD), ultraviolet–visible (UV-Vis) and Fourier transform -Raman (FT-Raman) spectroscopic techniques. The XRD analysis confirms that the oxidized MWCNTs exist in a hexagonal structure and the sharp XRD peak corresponds to the (002) Bragg’s reflection plane, which indicates that the MWCNTs have higher crystalline nature. The UV-Vis analysis confirms that the MWCNTs functionalized with the carboxylic acid. The red shift was observed corresponds to the D band in the Raman spectrum, which reveals that the reduced disordered graphitic structure of oxidized MWCNTs. The strong Raman peak was observed at 2563 cm{sup -1} corresponds to the overtone of the D band, which is the characteristic vibrational mode of oxidized MWCNTs. The carboxylic acid functionalization of MWCNTs enhances the dispersibility, which paves the way for potential applications in the field of biosensors and targeted drug delivery.

  14. Double-Windows-Based Motion Recognition in Multi-Floor Buildings Assisted by a Built-In Barometer.

    Science.gov (United States)

    Liu, Maolin; Li, Huaiyu; Wang, Yuan; Li, Fei; Chen, Xiuwan

    2018-04-01

    Accelerometers, gyroscopes and magnetometers in smartphones are often used to recognize human motions. Since it is difficult to distinguish between vertical motions and horizontal motions in the data provided by these built-in sensors, the vertical motion recognition accuracy is relatively low. The emergence of a built-in barometer in smartphones improves the accuracy of motion recognition in the vertical direction. However, there is a lack of quantitative analysis and modelling of the barometer signals, which is the basis of barometer's application to motion recognition, and a problem of imbalanced data also exists. This work focuses on using the barometers inside smartphones for vertical motion recognition in multi-floor buildings through modelling and feature extraction of pressure signals. A novel double-windows pressure feature extraction method, which adopts two sliding time windows of different length, is proposed to balance recognition accuracy and response time. Then, a random forest classifier correlation rule is further designed to weaken the impact of imbalanced data on recognition accuracy. The results demonstrate that the recognition accuracy can reach 95.05% when pressure features and the improved random forest classifier are adopted. Specifically, the recognition accuracy of the stair and elevator motions is significantly improved with enhanced response time. The proposed approach proves effective and accurate, providing a robust strategy for increasing accuracy of vertical motions.

  15. Experimental Air-Tightness Analysis in Mediterranean Buildings after Windows Retrofit

    Directory of Open Access Journals (Sweden)

    Francesca Romana d’Ambrosio Alfano

    2016-09-01

    Full Text Available Energy saving and Indoor Air Quality (IAQ in buildings are strongly affected by air leakages. Several studies reveal that the energy loss owing to leaky windows can account for up to 40% of the total building energy demand. Furthermore, at the design stage, the possible infiltration of outdoor air through windows is not taken into account when determining the nominal outdoor airflow rate of the ventilation system. This practice may result in an oversizing of the ventilation system and consequent energy waste. Thus, the air-tightness class of a wall assembly should be assessed for each window component considering the type of material, the presence of the seal, the type of closure, the sealing and the maintenance condition. In this paper, the authors present the experimental results of air-tightness measurements carried out using the fan pressurization method in three residential buildings located in the Mediterranean region before and after a window retrofit. Two different window retrofits were investigated: the application of rubber seals on window frames and the substitution of existing windows with new certified high performance windows. The effectiveness of such retrofits was estimated also in terms of energy saving. Test results demonstrated a high variability of the building air tightness after window retrofits, despite the fact that air tight–certified windows were used.

  16. A new approach combining analytical methods for workplace exposure assessment of inhalable multi-walled carbon nanotubes

    NARCIS (Netherlands)

    Tromp, P.C.; Kuijpers, E.; Bekker, C.; Godderis, L.; Lan, Q.; Jedynska, A.D.; Vermeulen, R.; Pronk, A.

    2017-01-01

    To date there is no consensus about the most appropriate analytical method for measuring carbon nanotubes (CNTs), hampering the assessment and limiting the comparison of data. The goal of this study is to develop an approach for the assessment of the level and nature of inhalable multi-wall CNTs

  17. A constructive heuristic for time-dependent multi-depot vehicle routing problem with time-windows and heterogeneous fleet

    Directory of Open Access Journals (Sweden)

    Behrouz Afshar-Nadjafi

    2017-01-01

    Full Text Available In this paper, we consider the time-dependent multi-depot vehicle routing problem. The objective is to minimize the total heterogeneous fleet cost assuming that the travel time between locations depends on the departure time. Also, hard time window constraints for the customers and limitation on maximum number of the vehicles in depots must be satisfied. The problem is formulated as a mixed integer programming model. A constructive heuristic procedure is proposed for the problem. Also, the efficiency of the proposed algorithm is evaluated on 180 test problems. The obtained computational results indicate that the procedure is capable to obtain a satisfying solution.

  18. Removal of oxidative fragments from chemically functionalized multi-walled carbon nanotubes (MWCNTs)

    International Nuclear Information System (INIS)

    Mohd Hamzah Harun; Whitby, Raymond; Khairul Zaman Dahlan; Nik Ghazali Nik Salleh; Mohd Sofian Alias; Mahathir Mohamed; Mohd Yusof Hamzah; Mohd Faizal Abdul Rahman

    2010-01-01

    Acid oxidized multi-walled carbon nano tubes (MWCNTs) were prepared by refluxing MWCNTs with nitric acid (70 %). To remove the oxidative fragment/ debris, in which partially attached onto the carbon nano tubes lattice, the functionalized MWCNTs (f-MWCNTs) then were refluxed with NaOH (1M) and followed with HCl (1M) wash. The presence of carboxylic group that covalently attached onto the MWCNTs lattice are confirmed with acid-base titration. The TEM image shows the comparison of pure MWCNTs, f-MWCNTs and base-acid wash of f-MWCNTs. (author)

  19. Co-transport of chlordecone and sulfadiazine in the presence of functionalized multi-walled carbon nanotubes in soils

    Science.gov (United States)

    Batch and saturated soil column experiments were conducted to investigate sorption and mobility of two 14C-labeled contaminants, the hydrophobic chlordecone (CLD) and the readily water-soluble sulfadiazine (SDZ), in the absence or presence of functionalized multi-walled carbon nanotubes (MWCNTs). Th...

  20. Synthesis of multi-layer graphene and multi-wall carbon nanotubes from direct decomposition of ethanol by microwave plasma without using metal catalysts

    International Nuclear Information System (INIS)

    Rincón, R; Melero, C; Jiménez, M; Calzada, M D

    2015-01-01

    The synthesis of nanostructured carbon materials by using microwave plasmas at atmospheric pressure is presented. This technique involves only one step and without any other supplementary chemical process or metal catalyst. Multi-layer graphene, multi-wall carbon nananotubes and H 2 were obtained by the plasma after ethanol decomposition. Strong emissions of both C 2 molecular bands and C carbon were emitted by the plasma during the process. Futhermore, plasma parameters were studied. Our research shows that both C 2 radicals and high gas temperatures (>3000 K) are required for the synthesis of these materials, which contribute to the understanding of materials synthesis by plasma processes. (fast track communication)

  1. Elasto-plastic response of multi-story shear wall structures

    International Nuclear Information System (INIS)

    Mizutani, M.; Yamazaki, F.

    1987-01-01

    A Monte Carlo simulation study is carried out. The relationship between the elastoplastic and linear response for multi-DOF systems is developed based on the results of the simulation study. Several 6-story shear wall structures are considered as structural models which represent typical nuclear power plant buildings. A bilinear force-displacement relationship is assumed for each story. A number of artificial earthquakes based on the Kanai-Tajimi power spectrum and trapezoidal envelope function are used as the input ground motion. The least square method is introduced for the purpose of evaluating the median relationship between the ductility factor and linear response from the simulated data and also evaluating the deviation from this median relationship. This relationship derived for the 6-story buildings is compared with the currently used energy absorption factor and the simulation results for Zion auxiliary building model. (orig./HP)

  2. Chlorophenols Sorption on Multi-Walled Carbon Nanotubes: DFT Modeling and Structure-Property Relationship Analysis

    OpenAIRE

    Watkins, Marquita; Sizochenko, Natalia; Moore, Quentarius; Golebiowski, Marek; Leszczynska, Danuta; Leszczynski, Jerzy

    2017-01-01

    Presence of chlorophenols in drinking water could be hazardous to human health. Optimization and computational modeling of experimental conditions of adsorption lead to understanding the mechanisms of this process and to creating the efficient experimental equipment. In the current study, we investigated multi-walled carbon nanotubes by means of density functional theory (DFT) approach. This is applied to study selected types of interactions between six solvents, five types of nanotubes, and ...

  3. Energy Efficient Triple IG Automation EEE (Triple-E)

    Energy Technology Data Exchange (ETDEWEB)

    McGlinchy, Timothy B

    2013-02-28

    GED Integrated Solutions collaborated with US window and door manufactures to investigate, design and verify technical and cost feasibility for producing high performance, high volume, low material and labor cost window, utilizing a modified window design containing a triple insulating glass unit (IGU). This window design approach when combined with a high volume IGU manufacturing system, can produce R5 rated windows for an approximate additional consumer cost of only $4 per square foot when compared to conventional Low-E argon dual pane IG windows, resulting in a verify practical, reliable and affordable high performance window for public use.

  4. Proper Installation of Replacement Windows | Efficient Windows

    Science.gov (United States)

    Collaborative Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring

  5. Effect of Novel Quercetin Titanium Dioxide-Decorated Multi-Walled Carbon Nanotubes Nanocomposite on Bacillus subtilis Biofilm Development

    DEFF Research Database (Denmark)

    Raie, Diana S; Mhatre, Eisha; El-Desouki, Doaa S

    2018-01-01

    The present work was targeted to design a surface against cell seeding and adhering of bacteria, Bacillus subtilis. A multi-walled carbon nanotube/titanium dioxide nano-power was produced via simple mixing of carbon nanotube and titanium dioxide nanoparticles during the sol-gel process followed...

  6. Preparing hydroxyapatite-silicon composite suspensions with homogeneous distribution of multi-walled carbon nano-tubes for electrophoretic coating of NiTi bone implant and their effect on the surface morphology

    International Nuclear Information System (INIS)

    Khalili, Vida; Khalil-Allafi, Jafar; Xia, Wei; Parsa, Alireza B.; Frenzel, Jan; Somsen, Christoph; Eggeler, Gunther

    2016-01-01

    Graphical abstract: - Highlights: • The stable composite suspensions of hydroxyapatite, silicon and multi-walled carbon nano-tubes was prepared using functionalization of and multi-walled carbon nano-tubes in HNO_3 vapor and triethanolamine as dispersing agent. • The zeta potential of composite suspensions is less than that of hydroxyapatite suspension. • The silicon particles presence in suspension causes to decrease the charge carrier in suspension and current density during electrophoretic deposition. • The orientation of multi-walled carbon nano-tubes to parallel direction of the applied electric field during electrophoretic deposition can facilitate their moving towards the cathode and increase current density. • The more zeta potential of suspension, the lower roughness of coatings during electrophoretic deposition. - Abstract: Preparing a stable suspension is a main step towards the electrophoretically depositing of homogeneous and dense composite coatings on NiTi for its biomedical application. In the present study, different composite suspensions of hydroxyapatite, silicon and multi-walled carbon nano-tubes were prepared using n-butanol and triethanolamine as media and dispersing agent, respectively. Multi-walled carbon nanotubes were first functionalized in the nitric acid vapor for 15 h at 175 °C, and then mixed into suspensions. Thermal desorption spectroscopy profiles indicate the formation of functional groups on multi-walled carbon nano-tubes. An excellent suspension stability can be achieved for different amounts of triethanolamine. The amount of triethanolamine can be increased by adding a second component to a stable hydroxyapatite suspension due to an electrostatic interaction between components in suspension. The stability of composite suspension is less than that of the hydroxyapatite suspension, due to density differences, which under the gravitational force promote the demixing. The scanning electron microscopy images of the

  7. Performance Standards for Windows | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  8. Benefits of Efficient Windows | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  9. Assessing Window Replacement Options | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  10. Windows for New Construction | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  11. Effect of dewatering on seismic performance of multi-anchor wall due to high ground water level

    Science.gov (United States)

    Kobayashi, Makoto; Miura, Kinya; Konami, Takeharu; Hayashi, Taketo; Sato, Hiroki

    2017-10-01

    Previous research reported that the ground water in the backfill of reinforced soil wall made it deteriorate. According to the damage investigation of Great East Earthquake 2011, the reinforced soil structure due to high ground water level by seismic wave were deformed remarkably. Some of them classified ultimate limit state or restorability limit state. However, more than 90% of reinforced soil structure, which suffered from this earthquake, were classified into no damage condition. Therefore, it is necessary that the seismic behaviors of multi-anchor wall due to seepage flow should be clarified in order to adopt the performance-based design in such reinforced soil structure. In this study, a series of centrifugal shaking table tests were conducted to investigate the seismic behavior of multi-anchor wall due to high ground water level. The reinforced drainage pipes were installed into the backfill in order to verify the dewatering effect and additional reinforcement. Furthermore, to check only the dewatering effect, the model tests was carried out with several ground water table that was modeled the case reinforced drainage pipes installed. The test results show unique behavior of reinforced region that moved integrally. This implies that the reinforced region has been behaved as if it became one mass, and this behavior make this structure increase seismic performance. Thus, the effectiveness of dewatering was observed remarkably because of decreasing the inertial force during earthquake.

  12. Ultrasound-aided formation of gold nanoparticles on multi-walled carbon nanotubes functionalized with mercaptobenzene moieties.

    Science.gov (United States)

    Park, Gle; Lee, Kyung G; Lee, Seok Jae; Park, Tae Jung; Wi, Ringbok; Wang, Kye Won; Kim, Do Hyun

    2011-07-01

    A hybrid of multi-walled carbon nanotube (MWCNT) and gold nanoparticle (Au NP) was prepared under ultrasound irradiation. The approach starts with the functionalization of the walls of MWCNTs with mercaptobenzene moieties for the subsequent immobilization of Au NPs. From the Raman spectra, mercaptobenzene was proven to exist on the MWCNTs. Gold ions were added to the aqueous dispersion of functionalized MWCNTs (f-MWCNTs), and were reduced with the aid of ultrasound and ammonium hydroxide. The reduced gold nanoparticles were examined from the TEM images. Au NPs adhered specifically on the thiol groups of mercaptobenzene to be deposited uniformly on the outer walls of the f-MWCNTs. The application of ultrasound led to a high yield of MWCNT-Au nanocomposites and to the dense distribution of the Au NPs. Moreover, the synthesis reaction rate of the hybrid was considerably enhanced relative to synthesis with mechanical agitation. Through an adsorption test using gold-binding-peptide-(GBP)-modified biomolecules, the hybrid's potential for biological diagnosis was verified.

  13. Close-range geophotogrammetric mapping of trench walls using multi-model stereo restitution software

    Energy Technology Data Exchange (ETDEWEB)

    Coe, J.A.; Taylor, E.M.; Schilling, S.P.

    1991-06-01

    Methods for mapping geologic features exposed on trench walls have advanced from conventional gridding and sketch mapping to precise close-range photogrammetric mapping. In our study, two strips of small-format (60 {times} 60) stereo pairs, each containing 42 photos and covering approximately 60 m of nearly vertical trench wall (2-4 m high), were contact printed onto eight 205 {times} 255-mm transparent film sheets. Each strip was oriented in a Kern DSR15 analytical plotter using the bundle adjustment module of Multi-Model Stereo Restitution Software (MMSRS). We experimented with several systematic-control-point configurations to evaluate orientation accuracies as a function of the number and position of control points. We recommend establishing control-point columns (each containing 2-3 points) in every 5th photo to achieve the 7-mm Root Mean Square Error (RMSE) accuracy required by our trench-mapping project. 7 refs., 8 figs., 1 tab.

  14. Close-range geophotogrammetric mapping of trench walls using multi-model stereo restitution software

    International Nuclear Information System (INIS)

    Coe, J.A.; Taylor, E.M.; Schilling, S.P.

    1991-01-01

    Methods for mapping geologic features exposed on trench walls have advanced from conventional gridding and sketch mapping to precise close-range photogrammetric mapping. In our study, two strips of small-format (60 x 60) stereo pairs, each containing 42 photos and covering approximately 60 m of nearly vertical trench wall (2-4 m high), were contact printed onto eight 205 x 255-mm transparent film sheets. Each strip was oriented in a Kern DSR15 analytical plotter using the bundle adjustment module of Multi-Model Stereo Restitution Software (MMSRS). We experimented with several systematic-control-point configurations to evaluate orientation accuracies as a function of the number and position of control points. We recommend establishing control-point columns (each containing 2-3 points) in every 5th photo to achieve the 7-mm Root Mean Square Error (RMSE) accuracy required by our trench-mapping project. 7 refs., 8 figs., 1 tab

  15. Disposable screen-printed bismuth electrode modified with multi-walled carbon nanotubes for electrochemical stripping measurements.

    Science.gov (United States)

    Niu, Xiangheng; Zhao, Hongli; Lan, Minbo

    2011-01-01

    Integrating the advantages of screen printing technology with the encouraging electroanalytical characteristic of metallic bismuth, we developed an ultrasensitive and disposable screen-printed bismuth electrode (SPBE) modified with multi-walled carbon nanotubes (MWCNTs) for electrochemical stripping measurements. Metallic bismuth powders and MWCNTs were homogeneously mixed with graphite-carbon ink to mass-prepare screen-printed bismuth electrode doped with multi-walled carbon nanotubes (SPBE/MWCNT). The electroanalytical performance of the prepared SPBE/MWCNT was intensively evaluated by measuring trace Hg(II) with square-wave anodic stripping voltammetry (SWASV). The results indicated that the SPBE modified with 2 wt% MWCNTs could offer a more sensitive response to trace Hg(II) than the bare SPBE. The stripping current obtained at SPBE/MWCNT was linear with Hg(II) concentration in the range from 0.2 to 40 µg/L (R(2) = 0.9976), with a detection limit of 0.09 µg/L (S/N = 3) under 180 s accumulation. The proposed "mercury-free" electrode, with extremely simple preparation and ultrahigh sensitivity, holds wide application prospects in both environmental and industrial monitoring. 2011 © The Japan Society for Analytical Chemistry

  16. Design method of high performance precast external walls for warm climate by multi-objective optimization analysis

    International Nuclear Information System (INIS)

    Baglivo, Cristina; Congedo, Paolo Maria

    2015-01-01

    Taking into account the global environmental problems, there is the urgent need to reduce energy consumption and the greenhouse gas emissions in the construction sector. Environmental awareness can be achieved through the extensive application of precast systems in buildings construction. A multi-criteria analysis has been used to obtain energy-efficient precast walls for Zero Energy Building in warm climate focusing on eco-friendly building materials. The modeFRONTIER optimization tool, with the use of computational procedures developed in Matlab, has been used to assess the thermal dynamics of building components. The optimization has been carried out in terms of steady thermal transmittance, periodic thermal transmittance, decrement factor, time shift, areal heat capacity, thermal admittance, surface mass, small thickness, eco sustainability score, light-weight and costs. The best sequences of layers show repetitive features: high surface mass for the first layer (internal side), followed by eco-friendly insulating materials for the middle layer and common insulating materials for the outer layer. The results illustrate that it is possible to obtain high performance precast multi-layered walls also with light and thin solutions; in particular, the superficial mass and the internal areal heat capacity have an important role to obtain the best performance in the warm climate. - Highlights: • Environmental awareness through the application of prefabrication systems. • The precast allows important benefits compared to traditional walls build in situ. • At the end of their useful life, the precast can be re-used. • Precast walls with very high efficiency for warm climates. • High internal areal heat capacity avoids events of overheating/cooling down.

  17. Simultaneous collection method of on-peak window image and off-peak window image in Tl-201 imaging

    International Nuclear Information System (INIS)

    Murakami, Tomonori; Noguchi, Yasushi; Kojima, Akihiro; Takagi, Akihiro; Matsumoto, Masanori

    2007-01-01

    Tl-201 imaging detects the photopeak (71 keV, in on-peak window) of characteristic X-rays of Hg-201 formed from Tl-201 decay. The peak is derived from 4 rays of different energy and emission intensity and does not follow in Gaussian distribution. In the present study, authors made an idea for the method in the title to attain the more effective single imaging, which was examined for its accuracy and reliability with phantoms and applied clinically to Tl-201 scintigraphy in a patient. The authors applied the triple energy window method for data acquisition: the energy window setting was made on Hg-201 X-rays photopeak in three of the lower (3%, L), main (72 keV, M) and upper (14%, U) windows with the gamma camera with 2-gated detector (Toshiba E. CAM/ICON). L, M and U images obtained simultaneously were then constructed to images of on-peak (L+M, Mock on-peak) and off-peak (M+U) window settings for evaluation. Phantoms for line source with Tl-201-containing swab and for multi-defect with acrylic plate containing Tl-201 solution were imaged in water. The female patient with thyroid cancer was subjected to preoperative scintigraphy under the defined conditions. Mock on-, off-peak images were found to be equivalent to the true (ordinary, clinical) on-, off-peak ones, and the present method was thought usable for evaluation of usefulness of off-peak window data. (R.T.)

  18. Direction sensitive bending sensors based on multi-wall carbon nanotube/epoxy nanocomposites

    International Nuclear Information System (INIS)

    Wichmann, Malte H G; Buschhorn, Samuel T; Boeger, Lars; Schulte, Karl; Adelung, Rainer

    2008-01-01

    In the present work, a direction sensitive bending strain sensor consisting of a single block of epoxy/multi-wall carbon nanotube composite was developed. Moreover, the manufacturing could be realized in a straightforward single-step processing route. The directional sensitivity to bending deformations is related to the change in electrical resistance, which becomes positive or negative, depending on the direction of bending deflection. This effect is achieved by generating a gradient in electrical conductivity throughout the material. The resistance versus strain behaviour of these devices is investigated in detail and related to the microstructure of the nanocomposites.

  19. Synthesis of multi-walled carbon nanotubes and their application in resin based nanocomposites

    International Nuclear Information System (INIS)

    Ahmad, Shahid Nisar; Hakeem, Saira; Alvi, Rashid Ahmed; Farooq, Khawar; Farooq, Naveed; Yasmin, Farida; Saeed, Sadaf

    2013-01-01

    Multi-walled carbon nanotubes (MWCNTs) were synthesized by catalytic decomposition of hydrocarbon gas using chemical vapor deposition method. Synthesis was done at different growth temperatures and catalyst ratios. These MWCNTs were dispersed in epoxy resin (E-51) and their effect on mechanical strength of epoxy nanocomposites was studied. Increase in the mechanical strength of epoxy was observed with the addition of CNTs. The surface characterization was done by using optical microscope and scanning electron microscope (SEM). Mechanical properties were determined by the general tensile strength testing method.

  20. Humidity Sensor Based on Multi-Walled Carbon Nanotube Thin Films

    International Nuclear Information System (INIS)

    Cao, C.L.; Hu, C.G.; Fang, L.; Wang, S.X.; Cao, C.L.; Tian, Y.S.; Pan, C.Y.

    2009-01-01

    The properties of the humidity sensors made of chemically treated and untreated multi-walled carbon nano tube (MWCNT) thin films are investigated systematically. It shows that both the chemically treated and untreated MWCNT thin films demonstrate humidity sensitive properties, but the former have stronger sensitivity than the latter. In the range of 11%-98% relative humidity (RH), the resistances of the chemically treated and untreated MWCNT humidity sensors increase 120% and 28%, respectively. Moreover, the treated humidity sensors showed higher sensitivity and better stability. In addition, the response and recover properties, and stabilization of the humidity sensors are measured, and the humidity sensitive mechanisms of the sensors are analyzed. The humidity sensitivity of carbon nano tube thin films indicates it promise as a kind of humidity sensitive material

  1. Soft purification of N-doped and undoped multi-wall carbon nanotubes

    International Nuclear Information System (INIS)

    Alvizo-Paez, Edgar Rogelio; Ruiz-Garcia, Jaime; Hernandez-Lopez, Jose Luis; Romo-Herrera, Jose Manuel; Terrones, Humberto; Terrones, Mauricio

    2008-01-01

    A soft method for purifying multi-wall carbon nanotubes (N-doped and undoped) is presented. The technique includes a hydrothermal/ultrasonic treatment of the material in conjunction with other subsequent treatments, including the extraction of polyaromatic compounds, dissolution of metal particles, bundle exfoliation, and uniform dispersion. This method avoids harsh oxidation protocols that burn (via thermal treatments) or functionalize (by introducing chemical groups) the nanotubes. We show a careful analysis of each purification step and demonstrate that the technique is extremely efficient when characterizing the materials using scanning electron microscopy (SEM), energy dispersive x-ray analysis (EDAX), scanning tuneling electron microscopy (STEM), x-ray powder diffraction (XRD), diffuse reflectance Fourier transform infrared (DRFTIR) spectroscopy and thermogravimetric analysis (TGA)

  2. Lateral resistance of plybamboo wall-panels

    OpenAIRE

    Gonzalez Beltran, G.E.; Herwijnen, van, F.; Janssen, J.J.A.; Moonen, S.P.G.; Gutierrez, J.A.

    2003-01-01

    This paper deals with the experimental and theoretical behavior of plybamboo (kind of plywood made out of bamboo) wall-panels subjected to lateral load. The wall-panels are part of a house design method proposed in the author's PhD thesis for prefabricated social housing in developing countries. Sixteen fullscaled wallpanels with or without window and door openings were tested and their theoretical capacities estimated. Design wind and seismic loads were determined according to the Internatio...

  3. Replacement Windows for Existing Homes Homes | Efficient Windows

    Science.gov (United States)

    Collaborative Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring

  4. Design Guidance for New Windows | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  5. Selection Process for New Windows | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  6. Selection Process for Replacement Windows | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  7. Design Guidance for Replacement Windows | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  8. Proper Installation of New Windows | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  9. SIP Shear Walls: Cyclic Performance of High-Aspect-Ratio Segments and Perforated Walls

    Science.gov (United States)

    Vladimir Kochkin; Douglas R. Rammer; Kevin Kauffman; Thomas Wiliamson; Robert J. Ross

    2015-01-01

    Increasing stringency of energy codes and the growing market demand for more energy efficient buildings gives structural insulated panel (SIP) construction an opportunity to increase its use in commercial and residential buildings. However, shear wall aspect ratio limitations and lack of knowledge on how to design SIPs with window and door openings are barriers to the...

  10. Molecular Dynamics Simulation of a Multi-Walled Carbon Nanotube Based Gear

    Science.gov (United States)

    Han, Jie; Globus, Al; Srivastava, Deepak; Chancellor, Marisa K. (Technical Monitor)

    1997-01-01

    We used molecular dynamics to investigate the properties of a multi-walled carbon nanotube based gear. Previous work computationally suggested that molecular gears fashioned from (14,0) single-walled carbon nanotubes operate well at 50-100 gigahertz. The gears were formed from nanotubes with teeth added via a benzyne reaction known to occur with C60. A modified, parallelized version of Brenner's potential was used to model interatomic forces within each molecule. A Leonard-Jones 6-12 potential was used for forces between molecules. The gear in this study was based on the smallest multi-walled nanotube supported by some experimental evidence. Each gear was a (52,0) nanotube surrounding a (37,10) nanotube with approximate 20.4 and 16,8 A radii respectively. These sizes were chosen to be consistent with inter-tube spacing observed by and were slightly larger than graphite inter-layer spacings. The benzyne teeth were attached via 2+4 cycloaddition to exterior of the (52,0) tube. 2+4 bonds were used rather than the 2+2 bonds observed by Hoke since 2+4 bonds are preferred by naphthalene and quantum calculations by Jaffe suggest that 2+4 bonds are preferred on carbon nanotubes of sufficient diameter. One gear was 'powered' by forcing the atoms near the end of the outside buckytube to rotate to simulate a motor. A second gear was allowed to rotate by keeping the atoms near the end of its outside buckytube on a cylinder. The ends of both gears were constrained to stay in an approximately constant position relative to each other, simulating a casing, to insure that the gear teeth meshed. The stiff meshing aromatic gear teeth transferred angular momentum from the powered gear to the driven gear. The simulation was performed in a vacuum and with a software thermostat. Preliminary results suggest that the powered gear had trouble turning the driven gear without slip. The larger radius and greater mass of these gears relative to the (14,0) gears previously studied requires a

  11. Orbital wall fractures

    International Nuclear Information System (INIS)

    Iinuma, Toshitaka; Ishio, Ken-ichirou; Yoshinami, Hiroyoshi; Kuriyama, Jun-ichi; Hirota, Yoshiharu.

    1993-01-01

    A total of 59 cases of mild facial fractures (simple orbital wall fractures, 34 cases, other facial fractures, 25 cases) with the clinical suspects of orbital wall fractures were evaluated both by conventional views (Waters' and Caldwell views) and coronal CT scans. Conventional views were obtained, as an average, after 4 days and CT after 7 days of injuries. Both the medial wall and the floor were evaluated at two sites, i.e., anterior and posterior. The ethmoid-maxillary plate was also included in the study. The degree of fractures was classified as, no fractures, fractures of discontinuity, dislocation and fragmentation. The coronal CT images in bone window condition was used as reference and the findings were compared between conventional views and CT. The correct diagnosis was obtained as follows: orbital floor (anterior, 78%, posterior, 73%), medial orbital wall (anterior, 72%, posterior, 72%) and ethmoid-maxillary plate (64%). The false positive diagnosis was as follows: orbital floor (anterior only, 13%), medial orbital wall (anterior only, 7%) and ethmoid-maxillary plate (11%). The false negative diagnosis was as follows: orbital floor (anterior, 9%, posterior, 10%), medial orbital wall (anterior, 21%, posterior, 28%) and ethmoid-maxillary plate (21%). The results were compared with those of others in the past. (author)

  12. Fabrication of Antibacterial Poly(Vinyl Alcohol Nanocomposite Films Containing Dendritic Polymer Functionalized Multi-Walled Carbon Nanotubes

    Directory of Open Access Journals (Sweden)

    Andreas Sapalidis

    2018-03-01

    Full Text Available A series of poly(vinyl alcohol (PVA nanocomposite films containing quaternized hyperbranched polyethyleneimine (PEI functionalized multi-walled carbon nanotubes (ox-CNTs@QPEI are prepared by solvent casting technique. The modified carbon-based material exhibits high aqueous solubility, due to the hydrophilic character of the functionalized hyperbranched dendritic polymer. The quaternized PEI successfully wraps around nanotube walls as polycations provide electrostatic repulsion. Various contents of ox-CNTs@QPEI ranging from 0.05 to 1.0% w/w were employed to prepare functionalized PVA nanocomposites. The developed films exhibit adequate optical transparency, improved mechanical properties and extremely high antibacterial behavior due to the excellent dispersion of the functionalized CNTs into the PVA matrix.

  13. SYNTHESIS AND STUDY OF CORROSION PERFORMANCE OF EPOXY COATING CONTAINING MULTI-WALLED CARBON NANOTUBE/ POLY ORTHO AMINOPHENOL NANOCOMPOSITE

    Directory of Open Access Journals (Sweden)

    N. Bahrami Panah

    2016-03-01

    Full Text Available The epoxy coatings containing multi-walled carbon nanotube/ poly ortho aminophenol nanocomposite were prepared and used as anticorrosive coatings. The nanocomposites with different contents of carbon nanotube were synthesized in a solution of sodium dodecyl sulfate and ammonium peroxy disulfate as a surfactant and an oxidant, respectively. The morphology and structural properties were confirmed by Fourier transform infrared spectroscopy and scanning electron microscopy methods. The mean size of nanocomposite particles was 20-35 nm determined by scanning electron microscopy. The epoxy coatings containing the nanocomposites were applied over mild steel panels and their corrosion performance was investigated using electrochemical impedance spectroscopy and potentiodynamic polarization measurements in a 3.5 % sodium chloride solution. The results showed that epoxy coatings consisting of nanocomposite with 1 wt.% multi-walled carbon nanotube exhibited higher anticorrosive properties than other prepared coatings of different carbon nanotube contents, which could be due to the strong interaction between the mild steel surface and the conjugated nanocomposite.

  14. Conducting polymer-coated, palladium-functionalized multi-walled carbon nanotubes for the electrochemical sensing of hydroxylamine

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eunhee; Ahmed, Mohammad Shamsuddin; You, Jung-Min; Kim, Seul Ki; Jeon, Seungwon, E-mail: swjeon@chonnam.ac.kr

    2012-08-31

    Electrochemical sensors of hydroxylamine were fabricated on glassy carbon electrodes (GCEs) by the electropolymerization of 3,4-ethylenedioxypyrrole (EDOP) and 3,4-ethylenedioxythiophene (EDOT) on palladium (Pd) nanoparticles attached to thiolated multi-walled carbon nanotubes (MWCNTs), denoted as PEDOP/MWCNT-Pd/GCE and PEDOT/MWCNT-Pd/GCE. The sensors were characterized by field emission scanning electron microscopy and electrochemical impedance spectroscopy. They showed strong catalytic activity toward the oxidation of hydroxylamine. Cyclic voltammetry and amperometry were used to characterize the sensors' performances. The detection limits of hydroxylamine by PEDOP/MWCNT-Pd/GCE and PEDOT/MWCNT-Pd/GCE were 0.22 and 0.24 {mu}M (S/N = 3), respectively. The sensors' sensitivity, selectivity, and stability were also investigated. - Highlights: Black-Right-Pointing-Pointer Multi-wall carbon nanotubes-Pd nanoparticles (MWCNT-Pd) based electrodes. Black-Right-Pointing-Pointer Electropolymerized electrodes by poly3,4-ethylenedioxythiophene(PEDOT). Black-Right-Pointing-Pointer PEDOT/MWCNT-Pd has a low detection limit of 0.24 Micro-Sign M for hydroxylamine. Black-Right-Pointing-Pointer PEDOT/MWCNT-Pd exhibits a wide linear range from 1 Micro-Sign M to 6 mM hydroxylamine. Black-Right-Pointing-Pointer The resulting sensor shows fast response and good stability.

  15. Immobilization of platinum nanoparticles on 3,4-diaminobenzoyl-functionalized multi-walled carbon nanotube and its electrocatalytic activity

    International Nuclear Information System (INIS)

    Choi, Hyun-Jung; Kang, Ji-Ye; Jeon, In-Yup; Eo, Soo-Mi; Tan, Loon-Seng; Baek, Jong-Beom

    2012-01-01

    Multi-walled carbon nanotubes (MWCNTs) are functionalized at the sp 2 C–H defect sites with 3,4-diaminobenzoic acid by a “direct” Friedel–Crafts acylation reaction in a mild polyphosphoric acid/phosphorous pentoxide medium. Owing to enhanced surface polarity, the resulting 3,4-diaminobenzoyl-functionalized MWCNTs (DAB-MWCNT) are highly dispersible in polar solvents, such as ethanol, N-methyl-2-pyrrolidone, and methanesulfonic acid. The absorption and emission properties of DAB-MWCNT in solution state are qualitatively shown to be sensitive to the pH in the environment. The DAB-MWCNT is used as a stable platform on which to deposit platinum nanoparticles (PNP). The PNP/DAB-MWCNT hybrid displays high electrocatalytic activity with good electrochemical stability for an oxygen reduction reaction under an alkaline condition.Graphical AbstractMulti-walled carbon nanotubes (MWCNTs) were functionalized with 3,4-diaminobenzoic acid to produce 3,4-diaminobenzoyl-functionalized MWCNT (DAB-MWCNT). Platinum nanoparticles (PNP) were deposited to DAB-MWCNT. The resulting PNP/DAB-MWCNT hybrid displayed high electrocatalytic activity.

  16. Enhancement in insulation and mechanical properties of PMMA nanocomposite foams infused with multi-walled carbon nanotubes.

    Science.gov (United States)

    Yeh, Jui-Ming; Chang, Kung-Chin; Peng, Chih-Wei; Lai, Mei-Chun; Hwang, Shyh-Shin; Lin, Hong-Ru; Liou, Shir-Joe

    2011-08-01

    In this study, PMMA/CNTs composite materials with carboxyl-multi walled carbon nanotubes (c-MWNTs) or untreated MWNTs were prepared via in-situ bulk polymerization. The as-prepared PMMA/CNTs composite materials were then characterized by Fourier-Transformation infrared (FTIR) spectroscopy, and transmission electron microscopy (TEM). The molecular weights of PMMA extracted from PMMA/CNTs composite materials and bulk PMMA were determined by gel permeation chromatography (GPC) with THF used as the eluant. The PMMA/CNTs composite materials were used to produce foams by a batch process in an autoclave using nitrogen as foaming agent. The cellular microstructure, insulation and compressive mechanical properties of PMMA/CNTs composite foams were also investigated in detail. Compared to neat PMMA foam, the presence of CNTs increases in cell density and reduces cell size. The insulation and compressive mechanical properties of PMMA/CNTs composite foams were found to improve substantially those of neat PMMA foam. In particular, 22.6% decrease in thermal conductivity, 19.7% decrease in dielectric constant and 160% increase in compressive modulus were observed with the addition of 0.3 wt% carboxyl-multi walled carbon nanotubes (c-MWNTs).

  17. Thermoplastic polyurethane and multi-walled carbon nanotubes nanocomposites for electrostatic dissipation

    International Nuclear Information System (INIS)

    Lavall, Rodrigo L.; Sales, Juliana A. de; Borges, Raquel S.; Calado, Hallen D. R.; Machado, Jose C.; Windmoeller, Dario; Silva, Glaura G.; Lacerda, Rodrigo G.; Ladeira, Luiz O.

    2010-01-01

    Polyurethane/multi-walled carbon nanotube (MWCNT) nanocomposites have been prepared with nanotube concentrations between 0.01 wt% and 1 wt%. MWCNT as-synthesized samples with ∼74 nm diameter and ∼7 mm length were introduced by solution processing in the polyurethane matrix. Scanning electron microscopy (SEM) images demonstrated good dispersion and adhesion of the CNTs to the polymeric matrix. The C=O stretching band showed evidence of perturbation of the hydrogen interaction between urethanic moieties in the nanocomposites as compared to pure TPU. Differential scanning calorimetry and positron annihilation lifetime spectroscopy measurements allowed the detection of glass transition displacement with carbon nanotube addition. Furthermore, the electrical conductivity of the nanocomposites was significantly increased with the addition of CNT. (author)

  18. Windows

    DEFF Research Database (Denmark)

    Heiselberg, Per; Svidt, Kjeld; Nielsen, Peter V.

    In natural ventilation systems fresh air is often provided through opening of windows. However, the knowledge of the performance of windows is rather limited. Computation of natural ventilation air flow through windows is most commonly made using discharge coefficients, that are regarded as being...... constant. The reported results show that the discharge coefficient for a window opening cannot be regarded as a constant and that it varies considerably with the size of the opening area, the window type and the temperature difference. Therefore, the use of a constant value can lead to serious errors...

  19. Analysis of Material Removal and Surface Characteristics in Machining Multi Walled Carbon Nanotubes Filled Alumina Composites by WEDM Process

    Directory of Open Access Journals (Sweden)

    Annebushan Singh Meinam

    2017-01-01

    Full Text Available The reinforcement of ceramic materials with electrically conductive particles increases the overall conductivity of the ceramic material. This allows the ceramic material to be more readily machined using wire electrical discharge machining process. The current work is an approach to identify the machinability of multi walled carbon nanotubes filled alumina composites in wire electrical discharge machining process. Alumina samples of 5 vol. % and 10 vol. % multi walled carbon nanotubes are machined and analysed for material removal rate and the surface characteristics. An increase in material removal rate is observed with increase in filler concentrations. At the same time, better surface roughness is observed. The surface characteristics of composite alumina are further compared with Monel 400 alloy. It has been observed that spalling action is the dominating material removal mechanism for alumina composites, while melting and evaporation is for the Monel 400 alloy.

  20. Comparative inhalation toxicity of multi-wall carbon nanotubes, graphene, graphite nanoplatelets and low surface carbon black.

    Science.gov (United States)

    Ma-Hock, Lan; Strauss, Volker; Treumann, Silke; Küttler, Karin; Wohlleben, Wendel; Hofmann, Thomas; Gröters, Sibylle; Wiench, Karin; van Ravenzwaay, Bennard; Landsiedel, Robert

    2013-06-17

    Carbon nanotubes, graphene, graphite nanoplatelets and carbon black are seemingly chemically identical carbon-based nano-materials with broad technological applications. Carbon nanotubes and carbon black possess different inhalation toxicities, whereas little is known about graphene and graphite nanoplatelets. In order to compare the inhalation toxicity of the mentioned carbon-based nanomaterials, male Wistar rats were exposed head-nose to atmospheres of the respective materials for 6 hours per day on 5 consecutive days. Target concentrations were 0.1, 0.5, or 2.5 mg/m3 for multi-wall carbon nanotubes and 0.5, 2.5, or 10 mg/m3 for graphene, graphite nanoplatelets and low-surface carbon black. Toxicity was determined after end of exposure and after three-week recovery using broncho-alveolar lavage fluid and microscopic examinations of the entire respiratory tract. No adverse effects were observed after inhalation exposure to 10 mg/m3 graphite nanoplatelets or relatively low specific surface area carbon black. Increases of lavage markers indicative for inflammatory processes started at exposure concentration of 0.5 mg/m3 for multi-wall carbon nanotubes and 10 mg/m3 for graphene. Consistent with the changes in lavage fluid, microgranulomas were observed at 2.5 mg/m3 multi-wall carbon nanotubes and 10 mg/m3 graphene. In order to evaluate volumetric loading of the lung as the key parameter driving the toxicity, deposited particle volume was calculated, taking into account different methods to determine the agglomerate density. However, the calculated volumetric load did not correlate to the toxicity, nor did the particle surface burden of the lung. The inhalation toxicity of the investigated carbon-based materials is likely to be a complex interaction of several parameters. Until the properties which govern the toxicity are identified, testing by short-term inhalation is the best option to identify hazardous properties in order to avoid unsafe applications or select

  1. Comparative inhalation toxicity of multi-wall carbon nanotubes, graphene, graphite nanoplatelets and low surface carbon black

    Science.gov (United States)

    2013-01-01

    Background Carbon nanotubes, graphene, graphite nanoplatelets and carbon black are seemingly chemically identical carbon-based nano-materials with broad technological applications. Carbon nanotubes and carbon black possess different inhalation toxicities, whereas little is known about graphene and graphite nanoplatelets. Methods In order to compare the inhalation toxicity of the mentioned carbon-based nanomaterials, male Wistar rats were exposed head-nose to atmospheres of the respective materials for 6 hours per day on 5 consecutive days. Target concentrations were 0.1, 0.5, or 2.5 mg/m3 for multi-wall carbon nanotubes and 0.5, 2.5, or 10 mg/m3 for graphene, graphite nanoplatelets and low-surface carbon black. Toxicity was determined after end of exposure and after three-week recovery using broncho-alveolar lavage fluid and microscopic examinations of the entire respiratory tract. Results No adverse effects were observed after inhalation exposure to 10 mg/m3 graphite nanoplatelets or relatively low specific surface area carbon black. Increases of lavage markers indicative for inflammatory processes started at exposure concentration of 0.5 mg/m3 for multi-wall carbon nanotubes and 10 mg/m3 for graphene. Consistent with the changes in lavage fluid, microgranulomas were observed at 2.5 mg/m3 multi-wall carbon nanotubes and 10 mg/m3 graphene. In order to evaluate volumetric loading of the lung as the key parameter driving the toxicity, deposited particle volume was calculated, taking into account different methods to determine the agglomerate density. However, the calculated volumetric load did not correlate to the toxicity, nor did the particle surface burden of the lung. Conclusions The inhalation toxicity of the investigated carbon-based materials is likely to be a complex interaction of several parameters. Until the properties which govern the toxicity are identified, testing by short-term inhalation is the best option to identify hazardous properties in

  2. The effect of different temperature profiles upon the length and crystallinity of vertically-aligned multi-walled carbon nanotubes.

    Science.gov (United States)

    Yun, Jongju; Lee, Cheesung; Zheng, Qing; Baik, Seunghyun

    2012-08-01

    We synthesized vertically-aligned multi-walled carbon nanotubes with an inner diameter of 1.6-7.5 nm and stack height of 80-28600 microm by chemical vapor deposition. The effects of synthesis conditions such as substrate position in the tube furnace, maximum temperature, temperature increasing rate and synthesis duration on the structure of nanotubes were investigated. It was found that slightly faster temperature increase rate resulted in significantly longer length, larger diameter and more defects of nanotubes. Structural parameters such as inner, outer diameters, wall thickness and defects were investigated using transmission electron microscopy and Raman spectroscopy.

  3. Multi-wall cask advantages with quarter-scale model drop test results for the NAC-STC Storable Transport Cask

    International Nuclear Information System (INIS)

    Danner, T.A.; Thompson, T.C.; Yaksh, M.C.

    1993-01-01

    Physical drop test results for a quarter-scale model multi-wall cask are presented for the 9 meter end, side and oblique drops with impact limiters, and for the 1 meter side and closure lid pin puncture drops. Lessons learned and final cask test qualification are presented. (J.P.N.)

  4. The effect of screening doors and windows on indoor density of Anopheles arabiensis in south-west Ethiopia: a randomized trial.

    Science.gov (United States)

    Massebo, Fekadu; Lindtjørn, Bernt

    2013-09-12

    Screening of houses might have impact on density of indoor host-seeking Anopheles mosquitoes. A randomized trial of screening windows and doors with metal mesh, and closing openings on eves and walls by mud was conducted to assess if reduce indoor densities of biting mosquitoes. Mosquitoes were collected in forty houses using Centers for Diseases Control and Prevention (CDC) light traps biweekly in March and April 2011. A randomization of houses into control and intervention groups was done based on the baseline data. Windows and doors of 20 houses were screened by metal mesh, and openings on the walls and eves closed by mud and the rest 20 houses were used as control group. Mosquitoes were collected biweekly in October and November 2011 from both control and intervention houses. A Generalized Estimating Equations (GEE) with a negative binomial error distribution was used to account for over dispersion of Anopheles arabiensis and culicine counts and repeated catches made in the same house. Screening doors and windows, and closing openings on eves and wall by mud reduced the overall indoor densities of An. arabiensis by 40%. The effect of screenings pronounced on unfed An. arabiensis by resulting 42% reduction in houses with interventions. The total costs for screening windows and doors, and to close openings on the eves and walls by mud was 7.34 USD per house. Screening houses reduced indoor density of An. arabiensis, and it was cheap and can easily incorporated into malaria vector strategies by local communities, but improving doors and windows fitness for screening should be considered during house construction to increase the efficacy of screenings.

  5. On the metalexicographic genre of dictionary reviews, with specific ...

    African Journals Online (AJOL)

    user

    ferent lexical words with the same word class, or when within the same word class different .... She looks sweet but if this little girl had really been a stargazer during .... 1. longish poster to be affixed, especially on glass panes and car windows.

  6. Glassy carbon electrode modified with multi-walled carbon nanotubes sensor for the quantification of antihistamine drug pheniramine in solubilized systems

    Directory of Open Access Journals (Sweden)

    Rajeev Jain

    2012-02-01

    Full Text Available A sensitive electroanalytical method for quantification of pheniramine in pharmaceutical formulation has been investigated on the basis of the enhanced electrochemical response at glassy carbon electrode modified with multi-walled carbon nanotubes in the presence of sodium lauryl sulfate. The experimental results suggest that the pheniramine in anionic surfactant solution exhibits electrocatalytic effect resulting in a marked enhancement of the peak current response. Peak current response is linearly dependent on the concentration of pheniramine in the range 200–1500 μg/mL with correlation coefficient 0.9987. The limit of detection is 58.31 μg/mL. The modified electrode shows good sensitivity and repeatability. Keywords: Pheniramine, Sodium lauryl sulfate (SLS, Glassy carbon electrode modified with multi-walled carbon nanotubes (GCE-MWCNTs, Solubilized systems, Voltammetric quantification

  7. Facile graft polystyrene onto multi-walled carbon nanotubes via in situ thermo-induced radical polymerization

    International Nuclear Information System (INIS)

    Liu Peng

    2009-01-01

    A facile procedure was developed for the grafting of polystyrene onto the surfaces of multi-walled carbon nanotubes (MWNTs) via the in situ thermo-induced bulk radical polymerization of styrene at the different polymerizing temperatures, in the presence of MWNTs without any initiator added. The grafting products were validated by the dispersibility, TEM, TGA, FT-IR, and Raman analysis. The TGA results also showed the lower polymerizing temperature was propitious to the free radical addition reactions.

  8. Removal of heavy metal ions from wastewaters using dendrimer-functionalized multi-walled carbon nanotubes.

    Science.gov (United States)

    Iannazzo, Daniela; Pistone, Alessandro; Ziccarelli, Ida; Espro, Claudia; Galvagno, Signorino; Giofré, Salvatore V; Romeo, Roberto; Cicero, Nicola; Bua, Giuseppe D; Lanza, Giuseppe; Legnani, Laura; Chiacchio, Maria A

    2017-06-01

    Dendrimer-functionalized multi-walled carbon nanotubes (MWCNT) for heavy metal ion removal from wastewaters were developed. Triazole dendrimers (TD) were built directly onto the carbon nanotube surface by successive click chemistry reactions affording the zero- and first-generation dendrimer-functionalized MWCNT (MWCNT-TD1 and MWCNT-TD2). The Moedritzer-Irani reaction carried out on the amino groups present on the MWCNT-TD2 sample gave the corresponding α-aminophosphonate nanosystem MWCNT-TD2P. Both MWCNT-TD2 and MWCNT-TD2P nanosystems have been characterized by physical, chemical, and morphological analyses. Their chelating abilities towards the toxic metal ions Pb 2+ , Hg 2+ , and Ni 2+ and the harmless Ca 2+ ion have been experimentally evaluated in the two different sets of experiments and at the salt concentrations of 1 mg/mL or 1 μg/mL by inductively coupled plasma mass spectrometry (ICP-MS). The results of these studies pointed out the interesting chelating behavior for the phosphonated nanosystem towards the Hg 2+ ion. The complexation mode of the best chelating system MWCNT-TD2P with mercury was investigated through density functional theory (DFT) calculations, suggesting a chelation mechanism involving the two oxygen atoms of the phosphate group. The synthesized dendrimers, supported on the multi-walled carbon nanotubes, have shown the potential to be used for the selective toxic metal ion removal and recovery.

  9. Fabrication and Characterization of Waterborne Multi-wall Carbon Nanotube Paints

    Science.gov (United States)

    Dowty, Heather; Wang, Chyi-Shan

    2005-04-01

    The fabrication of water-borne polyurethane nanocomposites containing multi-wall nanotubes has presented a significant technological challenge to those in the polymer community. Such conductive polyurethanes are of great interest to the paint and coatings industry for use in electrical grounding and shielding. Currently, these materials are formed by strong acidic reflux of the nanotubes and subsequent dispersal in the polymer matrix. This treatment can result in significant shortening of the tubes and degradation of the resulting mechanical and electrical transport properties. Here we present an alternate technique in which various conductive and non-conductive water-soluble polymers are physi-adsorbed to the surface of the nanotube. These interactions with the nanotubes result in highly uniform suspensions of water-based urethane coatings and bulk materials. We will examine the polymer chemistry and morphologies of these nanostructured materials and the resulting thermal, electrical and mechanical properties.

  10. Spontaneous and controlled-diameter synthesis of single-walled and few-walled carbon nanotubes

    Science.gov (United States)

    Inoue, Shuhei; Lojindarat, Supanat; Kawamoto, Takahiro; Matsumura, Yukihiko; Charinpanitkul, Tawatchai

    2018-05-01

    In this study, we explored the spontaneous and controlled-diameter growth of carbon nanotubes. We evaluated the effects of catalyst density, reduction time, and a number of catalyst coating on the substrate (for multi-walled carbon nanotubes) on the diameter of single-walled carbon nanotubes and the number of layers in few-walled carbon nanotubes. Increasing the catalyst density and reduction time increased the diameters of the carbon nanotubes, with the average diameter increasing from 1.05 nm to 1.86 nm for single-walled carbon nanotubes. Finally, we succeeded in synthesizing a significant double-walled carbon nanotube population of 24%.

  11. Multiple functionalization of multi-walled carbon nanotubes with carboxyl and amino groups

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Zhiyuan [College of Chemistry and Chemical Engineering, Central South University, Changsha 410083 (China); Yang, Zhanhong, E-mail: zhongnan320@gmail.com [College of Chemistry and Chemical Engineering, Central South University, Changsha 410083 (China); Key Laboratory of Resource Chemistry of Nonferrous Metals, Ministry of Education, Central South University, Changsha 410083 (China); Hu, Youwang; Li, Jianping [College of Mechanical and Electrical Engineering, Central South University, Changsha 410083 (China); Fan, Xinming [College of Chemistry and Chemical Engineering, Central South University, Changsha 410083 (China)

    2013-07-01

    In this paper, carboxyl and amino groups have been introduced onto the surface of the multi-walled carbon nanotubes (MWCNTs) by the mixed acid treatment and the diazonium reaction, respectively. The presence of multifunctionality groups on the MWCNTs has been characterized by Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric (TGA) analysis, Raman spectra, scanning electron microscopy (SEM) and energy dispersive X-ray spectrum (EDS). The multifunctionalized carbon nanotubes were further utilized to react with acetyl chloride and ethylenediamine (EDA). The formation of the amide bond in the grafting reaction has been confirmed by FT-IR spectroscopy. The result indicates that the further grafting is successful. The multifunctionalized MWCNTs can be a new versatile platform for many interesting applications.

  12. Micro/Nanomechanical characterization of multi-walled carbon nanotubes reinforced epoxy composite.

    Science.gov (United States)

    Cui, Peng; Wang, Xinnan; Tangpong, X W

    2012-11-01

    In this paper, the mechanical properties of 1 wt.% multi-walled carbon nanotubes (MWCNTs) reinforced epoxy nanocomposites were characterized using a self-designed micro/nano three point bending tester that was on an atomic force microscope (AFM) to in situ observe MWCNTs movement on the sample surface under loading. The migration of an individual MWCNT at the surface of the nanocomposite was tracked to address the nanomechanical reinforcing mechanism of the nanocomposites. Through morphology analysis of the nanocomposite via scanning electron microscopy, AFM, and digital image correlation technique, it was found that the MWCNTs agglomerate and the bundles were the main factors for limiting the bending strength of the composites. The agglomeration/bundle effect was included in the Halpin-Tsai model to account for the elastic modulus of the nanocomposites.

  13. Metal octacarboxyphthalocyanine / multi-walled carbon nanotube hybrid for the development of dye solar cells

    CSIR Research Space (South Africa)

    Mphahlele, N

    2013-09-01

    Full Text Available overall efficiencies even though it was lower than unexpected. Nevertheless, the TiO2/ZnOCPc/MWCNT performed better with the efficiency of about 0.1% than TiO2/SiOCPc/MWCNT and TiO2/GaOCPc/MWCNT. These findings open up avenues for improving... Conditions 50 3.3 FUNCTIONALISATION OF MULTI-WALLED CARBON NANOTUBES 51 3.4 PURIFICATION AND OXIDATION OF MWCNT 51 3.4.1 Amine-Functionalised MWCNT 52 3.5 SYTHESIS OF METAL 2,3,9,10,16,17,23,24 OCTACARBOXYPHTHALOCYANINES 52 3.5.1 Synthesis...

  14. The economics of window selection: An incremental approach

    International Nuclear Information System (INIS)

    Dixon, W.T.

    1993-01-01

    The options available to Energy Service Companies when improving the energy performance of an existing building are often driven by short-term payback cycles. The value of a measure is based on how quickly it pays for itself. The more quickly the energy savings created by the measure exceed the cost of purchasing and installing the measure, the more comfortable the engineer feels recommending that improvement. In the best cases, the short-term approach will quickly retire the debts associated with a particular retrofit and provide a dependable, albeit limited net savings stream for the property owner. The engineer has obtained energy savings for his client. The problem with this short-term approach is that it automatically eliminates other conservation measures which, over longer time horizons, could add far more value for the customer. The installation of new, extremely energy efficient replacement windows is a case in point. During preliminary discussions with our clients, (typically Public Housing Authorities or owners of subsidized, multi-family housing), the conversation eventually turns to the issue of replacement windows. The perception is that new windows are a luxury. The decision to install new windows is driven by maintenance costs and, in some cases, resident complaints over operability or draftiness associated with the existing windows. Typically the windows are not handled as part of the mainstream energy conservation program. If the client has already installed new windows, he probably based his selection on the low bidder of a unit that has marginal thermal performance. Every property has a budget and compromises must often be made to meet budgets. The purchaser may have not gotten the Cadillac of windows, but at least he got a good deal on the window that he did buy. His maintenance problems have been solved for the near term and resident complaints have gone down, for now

  15. The Palatal Window for Treating an Incompletely Augmented Maxillary Sinus.

    Science.gov (United States)

    Florio, Salvatore; Suzuki, Takanori; Cho, Sang-Choon

    2017-04-01

    Maxillary sinus augmentation through a lateral window is reported as one of the most predictable bone augmentation procedures before implant placement. The elevation of the membrane represents a delicate and crucial step that allows the creation of the space for the bone graft material. If the elevation is not completed, the regenerated bone might be inadequate for the implant placement. In this case, a new intervention will be necessary to complete the bone augmentation. Reaccessing from a lateral window, however, would be challenging due to thickness of the buccal boney wall because of the first grafting procedure; therefore, a different approach has to be used. The aim of this case report is to present the palatal window technique for treating incompletely augmented maxillary sinus. The detailed step-by-step diagnostic and surgical procedures are described, and the advantages and limitations of the technique are discussed through a review of the literature.

  16. The impact of different multi-walled carbon nanotubes on the X-band microwave absorption of their epoxy nanocomposites.

    Science.gov (United States)

    Che, Bien Dong; Nguyen, Bao Quoc; Nguyen, Le-Thu T; Nguyen, Ha Tran; Nguyen, Viet Quoc; Van Le, Thang; Nguyen, Nieu Huu

    2015-01-01

    Carbon nanotube (CNT) characteristics, besides the processing conditions, can change significantly the microwave absorption behavior of CNT/polymer composites. In this study, we investigated the influence of three commercial multi-walled CNT materials with various diameters and length-to-diameter aspect ratios on the X-band microwave absorption of epoxy nanocomposites with CNT contents from 0.125 to 2 wt%, prepared by two dispersion methods, i.e. in solution with surfactant-aiding and via ball-milling. The laser diffraction particle size and TEM analysis showed that both methods produced good dispersions at the microscopic level of CNTs. Both a high aspect ratio resulting in nanotube alignment trend and good infiltration of the matrix in the individual nanotubes, which was indicated by high Brookfield viscosities at low CNT contents of CNT/epoxy dispersions, are important factors to achieve composites with high microwave absorption characteristics. The multi-walled carbon nanotube (MWCNT) with the largest aspect ratio resulted in composites with the best X-band microwave absorption performance, which is considerably better than that of reported pristine CNT/polymer composites with similar or lower thicknesses and CNT loadings below 4 wt%. A high aspect ratio of CNTs resulting in microscopic alignment trend of nanotubes as well as a good level of micro-scale CNT dispersion resulting from good CNT-matrix interactions are crucial to obtain effective microwave absorption performance. This study demonstrated that effective radar absorbing MWCNT/epoxy nanocomposites having small matching thicknesses of 2-3 mm and very low filler contents of 0.25-0.5 wt%, with microwave energy absorption in the X-band region above 90% and maximum absorption peak values above 97%, could be obtained via simple processing methods, which is promising for mass production in industrial applications. Graphical AbstractComparison of the X-band microwave reflection loss of epoxy composites of

  17. Silica-coated multi-walled carbon nanotubes impregnated with polyethyleneimine for carbon dioxide capture under the flue gas condition

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Min-Sang; Park, Soo-Jin, E-mail: sjpark@inha.ac.kr

    2015-03-15

    In this study, silica-coated multi-walled carbon nanotubes impregnated with polyethyleneimine (PEI) were prepared via a two-step process: (i) hydrolysis of tetraethylorthosilicate onto multi-walled carbon nanotubes, and (ii) impregnation of PEI. The adsorption properties of CO{sub 2} were investigated using CO{sub 2} adsorption–desorption isotherms at 298 K and thermogravimetric analysis under the flue gas condition (15% CO{sub 2}/85% N{sub 2}). The results obtained in this study indicate that CO{sub 2} adsorption increases after impregnation of PEI. The increase in CO{sub 2} capture was attributed to the affinity between CO{sub 2} and the amine groups. CO{sub 2} adsorption–desorption experiments, which were repeated five times, also showed that the prepared adsorbents have excellent regeneration properties. - Graphical abstract: Fabrication and CO{sub 2} adsorption process of the S-MWCNTs impregnated with PEI. - Highlights: • Silica coated-MWCNT impregnated with PEI was synthesized. • Amine groups of PEI gave CO{sub 2} affinity sites on MWCNT surfaces. • The S-MWCNT/PEI(50) exhibited the highest CO{sub 2} adsorption capacity.

  18. Dynamical response of multi-walled carbon nanotube resonators based on continuum mechanics modeling for mass sensing applications

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Myungseok; Olshevskiy, Alexander; Kim, Chang-Wan [Konkuk University, Seoul (Korea, Republic of); Eom, Kilho [Sungkyunkwan University, Suwon (Korea, Republic of); Gwak, Kwanwoong [Sejong University, Seoul (Korea, Republic of); Dai, Mai Duc [Ho Chi Minh City University of Technology and Education, Ho Chi Minh (Viet Nam)

    2017-05-15

    Carbon nanotube (CNT) has recently received much attention due to its excellent electromechanical properties, indicating that CNT can be employed for development of Nanoelectromechanical system (NEMS) such as nanomechanical resonators. For effective design of CNT-based resonators, it is required to accurately predict the vibration behavior of CNT resonators as well as their frequency response to mass adsorption. In this work, we have studied the vibrational behavior of Multi-walled CNT (MWCNT) resonators by using a continuum mechanics modeling that was implemented in Finite element method (FEM). In particular, we consider a transversely isotropic hollow cylinder solid model with Finite element (FE) implementation for modeling the vibration behavior of Multi-walled CNT (MWCNT) resonators. It is shown that our continuum mechanics model provides the resonant frequencies of various MWCNTs being comparable to those obtained from experiments. Moreover, we have investigated the frequency response of MWCNT resonators to mass adsorption by using our continuum model with FE implementation. Our study sheds light on our continuum mechanics model that is useful in predicting not only the vibration behavior of MWCNT resonators but also their sensing performance for further effective design of MWCNT- based NEMS devices.

  19. The experimental study of the effect of microwave on the physical properties of multi-walled carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Haque, A.K.M. Mahmudul [Department of Ocean System Engineering, Gyeongsang National University, Cheondaegukchi-Gil 38, Tongyeong, Gyeongnam 650-160 (Korea, Republic of); Oh, Geum Seok; Kim, Taeoh [Department of Energy and Mechanical Engineering, Gyeongsang National University, Cheondaegukchi-Gil 38, Tongyeong, Gyeongnam 650-160 (Korea, Republic of); Kim, Junhyo [Department of Marine Engineering, Mokpo National Maritime University Haeyangdaehang-Ro 91, Mokpo-si, Jeollanam-do (Korea, Republic of); Noh, Jungpil; Huh, Sunchul; Chung, Hanshik [Department of Energy and Mechanical Engineering, Gyeongsang National University, Institute of Marine Industry, Cheondaegukchi-Gil 38, Tongyeong, Gyeongnam 650-160 (Korea, Republic of); Jeong, Hyomin, E-mail: hmjeong@gnu.ac.kr [Department of Energy and Mechanical Engineering, Gyeongsang National University, Institute of Marine Industry, Cheondaegukchi-Gil 38, Tongyeong, Gyeongnam 650-160 (Korea, Republic of)

    2016-01-15

    Highlights: • We study the microwave effect on the multi-walled carbon nanotubes (MWCNTs). • We examine the non uniform heating effect on the physical structure of MWCNTs. • We examine the purification of MWCNTs by microwave. • We analyze the thermal characteristics of microwave treated MWCNTs. - Abstract: This paper reports the effect of microwave on the physical properties of multi-walled carbon nanotubes (MWCNTs) where different power levels of microwave were applied on MWCNTs in order to apprehend the effect of microwave on MWCNTs distinctly. A low energy ball milling in aqueous circumstance was also applied on both MWCNTs and microwave treated MWCNTs. Temperature profile, morphological analysis by field emission scanning electron microscopy (FESEM), defect analysis by Raman spectroscopy, thermal conductivity, thermal diffusivity as well as heat transfer coefficient enhancement ratio were studied which expose some strong witnesses of the effect of microwave on the both purification and dispersion properties of MWCNTs in base fluid distilled water. The highest thermal conductivity enhancement (6.06% at 40 °C) of MWCNTs based nanofluid is achieved by five minutes microwave treatment as well as wet grinding at 500 rpm for two hours.

  20. The experimental study of the effect of microwave on the physical properties of multi-walled carbon nanotubes

    International Nuclear Information System (INIS)

    Haque, A.K.M. Mahmudul; Oh, Geum Seok; Kim, Taeoh; Kim, Junhyo; Noh, Jungpil; Huh, Sunchul; Chung, Hanshik; Jeong, Hyomin

    2016-01-01

    Highlights: • We study the microwave effect on the multi-walled carbon nanotubes (MWCNTs). • We examine the non uniform heating effect on the physical structure of MWCNTs. • We examine the purification of MWCNTs by microwave. • We analyze the thermal characteristics of microwave treated MWCNTs. - Abstract: This paper reports the effect of microwave on the physical properties of multi-walled carbon nanotubes (MWCNTs) where different power levels of microwave were applied on MWCNTs in order to apprehend the effect of microwave on MWCNTs distinctly. A low energy ball milling in aqueous circumstance was also applied on both MWCNTs and microwave treated MWCNTs. Temperature profile, morphological analysis by field emission scanning electron microscopy (FESEM), defect analysis by Raman spectroscopy, thermal conductivity, thermal diffusivity as well as heat transfer coefficient enhancement ratio were studied which expose some strong witnesses of the effect of microwave on the both purification and dispersion properties of MWCNTs in base fluid distilled water. The highest thermal conductivity enhancement (6.06% at 40 °C) of MWCNTs based nanofluid is achieved by five minutes microwave treatment as well as wet grinding at 500 rpm for two hours.

  1. 11 Foot Unitary Plan Tunnel Facility Optical Improvement Large Window Analysis

    Science.gov (United States)

    Hawke, Veronica M.

    2015-01-01

    The test section of the 11 by 11-foot Unitary Plan Transonic Wind Tunnel (11-foot UPWT) may receive an upgrade of larger optical windows on both the North and South sides. These new larger windows will provide better access for optical imaging of test article flow phenomena including surface and off body flow characteristics. The installation of these new larger windows will likely produce a change to the aerodynamic characteristics of the flow in the Test Section. In an effort understand the effect of this change, a computational model was employed to predict the flows through the slotted walls, in the test section and around the model before and after the tunnel modification. This report documents the solid CAD model that was created and the inviscid computational analysis that was completed as a preliminary estimate of the effect of the changes.

  2. Electrochemical parameters of ethamsylate at multi-walled carbon nanotube modified glassy carbon electrodes.

    Science.gov (United States)

    Wang, Sheng-Fu; Xu, Qiao

    2007-05-01

    In this paper, some electrochemical parameters of ethamsylate at a multi-walled carbon nanotube modified glassy carbon electrode, such as the charge number, exchange current density, standard heterogeneous rate constant and diffusion coefficient, were measured by cyclic voltammetry, chronoamperometry and chronocoulometry. The modified electrode exhibits good promotion of the electrochemical reaction of ethamsylate and increases the standard heterogeneous rate constant of ethamsylate greatly. The differential pulse voltammetry responses of ethamsylate were linearly dependent on its concentrations in a range from 2.0 x 10(-6) to 6.0 x 10(-5) mol L(-1), with a detection limit of 4.0 x 10(-7) mol L(-1).

  3. Long-term hepatotoxicity of polyethylene-glycol functionalized multi-walled carbon nanotubes in mice

    Science.gov (United States)

    Zhang, Danying; Deng, Xiaoyong; Ji, Zongfei; Shen, Xizhong; Dong, Ling; Wu, Minghong; Gu, Taoying; Liu, Yuanfang

    2010-04-01

    The toxicity of polyethylene-glycol functionalized (PEGylated) multi-walled carbon nanotubes (MWCNTs) and non-PEGylated MWCNTs in vivo was evaluated and compared. Mice were exposed to MWCNTs by intravenous injection. The activity level of glutathione, superoxide dismutase and gene expression in liver, as well as some biochemical parameters and the tumor necrosis factor alpha level in blood were measured over 2 months. The pathological and electron micrographic observations of liver evidently indicate that the damage caused by non-PEGylated MWCNTs is slightly more severe than that of PEGylated MWCNTs, which means that PEGylation can partly, but not substantially, improve the in vivo biocompatibility of MWCNTs.

  4. 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

    2010-11-01

    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...

  5. The functionalization and characterization of multi-walled carbon nanotubes (MWCNTs)

    Energy Technology Data Exchange (ETDEWEB)

    Abdullah, Mohd Pauzi [School of Chemical Sciences and Food Technology, Faculty Science and Technology, Universiti Kebangsaan Malaysia, 43600, Bangi, Selangor (Malaysia); Center of Water Analysis and Research (ALIR), Universiti Kebangsaan Malaysia, 43600, Bangi, Selangor (Malaysia); Zulkepli, Siti Aminah [School of Chemical Sciences and Food Technology, Faculty Science and Technology, Universiti Kebangsaan Malaysia, 43600, Bangi, Selangor (Malaysia)

    2015-09-25

    Functionalization is the process of introducing chemical functional groups on the surface of the material. In this study, a multi-walled carbon nanotube (MWCNTs) was functionalized by oxidation treatment using concentrated nitric acid. The functionalized and pristine MWCNTs were analyzed by using Fourier Transform Infrared Spectroscopy (FT-IR) and X-Ray Diffraction (XRD). The XRD patterns exhibit the graphitic properties for all samples. Besides, the XRD results also demonstrate that the percent of crystallinity of MWCNTs increases as the duration of acid treatment increases. The percent of crystallinity increases from 66% to 80% when the pristine MWCNT treated for 12 hours with additional 12 hours reflux process with nitric acid. The IR spectrum for the 12 hours-treated MWCNTs shows the formation of carboxyl functional group. Additional 12 hours reflux process with nitric acid on the 12 hours-treated MWCNTs have shown the loss of existing carboxyl group and only hydroxyl group formed.

  6. Electrocatalytic behahiour of cobalt tetraamino-phthalocyanine in the presence of a composite of reduced graphene nanosheets and of multi-walled carbon nanotubes

    International Nuclear Information System (INIS)

    Nyoni, Stephen; Nyokong, Tebello

    2014-01-01

    Graphical abstract: A composite of multi-walled carbon nanotubes, reduced graphene nanosheets and cobalt tetraamino phthalocyanine was used for electrode modification, resulting in a rough surface as judged by scanning electrochemical microscopy. - Highlights: • Conjugates of multi-walled carbon nanotubes and reduced graphene nanosheets were used to modify glassy carbon electrode. • The electrode was further modified with cobalt tetraamino phthalocyanine. • The modified electrode was employed for the detection of paraquat. • A mechanism for paraquat detection using the composite electrodes is proposed. - Abstract: A composite of multi-walled carbon nanotubes (MWCNT) with reduced graphene nanosheets (rGNS-2) was developed in order to minimize the restacking of the latter. The composite was used to modify a glassy carbon electrode (GCE). GCE was further modified with cobalt tetraamino phthalocyanine (CoTAPc). The modified electrode is represented as rGNS-2-MWCNT-CoTAPc-GCE. X-ray photoelectron spectroscopy, transmission electron microscopy, scanning electrochemical microscopy and Raman spectroscopy were used to explore into surface functionalities, morphology and topography of the nanocomposite. The rGNS-2-MWCNT-CoTAPc-GCE had a low limit of detection of 3.32 × 10 −8 M towards the detection of paraguat as a test analyte. A mechanism for paraquat detection using an rGNS-2-MWCNT-CoTAPc-GCE is also proposed in this work

  7. Structural design study of a proton beam window for a 1-MW spallation neutron source

    CERN Document Server

    Teraoku, T; Ishikura, S; Kaminaga, M; Maekawa, F; Meigo, S I; Terada, A

    2003-01-01

    A 1-MW spallation neutron source aiming at materials and life science researches will be constructed under the JAERI-KEK High-intensity Proton Accelerator Project (J-PARC). A proton beam passes through a proton beam window, and be injected into a target of the neutron source. The proton beam window functions as a boundary wall between a high vacuum area in the proton beam line and a helium atmosphere at about atmospheric pressure in a helium vessel which contains the target and moderators. The proton beam window is cooled by light water because high heat-density is generated in the window material by interactions with the proton beam. Then, uniformity of the water flow is requested at the window to suppress a hot-spot that causes excessive thermal stress and cooling water boiling. Also, the window has to be strong enough in its structure for inner stress due to water pressure and thermal stress due to heat generation. In this report, we propose two types of proton beam windows; one flat-type that is easy to m...

  8. Dynamic Behavior of Nanocomposites Reinforced with Multi-Walled Carbon Nanotubes (MWCNTs

    Directory of Open Access Journals (Sweden)

    Chun-Yu Lai

    2013-06-01

    Full Text Available The influence of multi-walled carbon nanotubes (MWCNT on the structural dynamic behavior of MWCNT/epoxy nanocomposites was investigated. Two different types of MWCNTs, pristine MWCNT and functionalized MWCNT, were used in this study. Carboxylic acid-functionalized MWCNTs (MWCNT-COOH were obtained by oxidation pristine MWCNTs via sonication in sulfuric-nitric acid and characterized by Fourier transform infrared spectroscopy (FTIR. Dynamic behaviors of the MWCNT reinforced nanocomposite including the natural frequency and damping ratio were determined using free vibration test. Experimental results showed that the damping ratio of the nanocomposite decreases with the increase of the MWCNT addition, while the natural frequency is increasing with the increase of the MWCNT addition. Functionalized MWCNTs improved the interfacial bonding between the nanotubes and epoxy resin resulting in the reduction of the interfacial energy dissipation ability and enhancement of the stiffness.

  9. Synthesis of MnO{sub 2}/short multi-walled carbon nanotube nanocomposite for supercapacitors

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jinhui; Wang, Yanhui; Zang, Jianbing, E-mail: diamondzjb@163.com; Xin, Guoxiang; Ji, Huiying; Yuan, Yungang

    2014-01-15

    Multi-walled carbon nanotubes (MWNTs) were selectively etched in molten nitrate to produce short MWNTs (s-MWNTs). MnO{sub 2}/s-MWNT nanocomposite was synthesized by a reduction of potassium permanganate under microwave irradiation. For comparative purpose, MnO{sub 2}/MWNT nanocomposite was also synthesized and investigated for its physical and electrochemical performance. Uniform and conformal MnO{sub 2} coatings were more easily formed on the surfaces of individual s-MWNTs. MnO{sub 2}/s-MWNT nanocomposite estimated by cyclic voltammetry (CV) in 0.5 M Na{sub 2}SO{sub 4} aqueous solution had the specific capacitance as high as 392.1 F g{sup −1} at 2 mV s{sup −1}. This value was more than 48.9% larger than MnO{sub 2}/s-MWNT nanocomposite. In addition, MnO{sub 2}/s-MWNT nanocomposite was also examined by repeating the CV test at a scan rate of 50 mV s{sup −1}, exhibiting an excellent cycling stability along with 99.2% specific capacitance retained after 1000 cycles. Therefore, MnO{sub 2}/s-MWNT nanocomposite is a promising electrode material in the supercapacitors. - Highlights: • Multi-walled carbon nanotubes are etched in molten nitrate to produce short MWNTs. • S-MWNTs can form more stable suspensions than did the pristine MWNTs. • Nano-scaled MnO{sub 2} is more effectively dispersed on the surface of the s-MWNTs. • This microstructure promotes the electrical conductivity of the electrode. • The electrode exhibits high specific capacitance and a cycle stability.

  10. Different cellular response mechanisms contribute to the length-dependent cytotoxicity of multi-walled carbon nanotubes

    OpenAIRE

    Liu, Dun; Wang, Lijun; Wang, Zhigang; Cuschieri, Alfred

    2012-01-01

    To date, there has not been an agreement on the best methods for the characterisation of multi-walled carbon nanotube (MWCNT) toxicity. The length of MWCNTs has been identified as a factor in in vitro and in vivo studies, in addition to their purity and biocompatible coating. Another unresolved issue relates to the variable toxicity of MWCNTs on different cell types. The present study addressed the effects of MWCNTs' length on mammalian immune and epithelial cancer cells RAW264.7 and MCF-7, r...

  11. Windows Azure

    CERN Document Server

    Johnson, Bruce; Chambers, James; Garber, Danny; Malik, Jamal; Fazio, Adam

    2013-01-01

    A collection of five must-have Azure titles, from some of the biggest names in the field Available individually, but at a discounted rate for the collection, this bundle of five e-books covers key developer and IT topics of Windows Azure, including ASP.NET, mobile services, web sites, data storage, and the hybrid cloud. A host of Microsoft employees and MPVs come together to cover the biggest challenges that professionals face when working with Windows Azure. The e-books included are as follows: Windows Azure and ASP.NET MVC MigrationWindows Azure Mobile ServicesWindows Azure Web SitesWindows

  12. GEODSS Present Configuration and Potential

    Science.gov (United States)

    2014-06-28

    to provide critical metric tracking capacity for deep space catalog maintenance. The follow-up TOS designed as a deployable gap filler in SSN deep...CASTOR) - A RAVEN System In Canada [3]WindowPane Observatory Lanphier Shutter System 2014 Retrieved From: http://windowpaneobservatory.com/ [4]J.N

  13. Multi-robot control interface

    Science.gov (United States)

    Bruemmer, David J [Idaho Falls, ID; Walton, Miles C [Idaho Falls, ID

    2011-12-06

    Methods and systems for controlling a plurality of robots through a single user interface include at least one robot display window for each of the plurality of robots with the at least one robot display window illustrating one or more conditions of a respective one of the plurality of robots. The user interface further includes at least one robot control window for each of the plurality of robots with the at least one robot control window configured to receive one or more commands for sending to the respective one of the plurality of robots. The user interface further includes a multi-robot common window comprised of information received from each of the plurality of robots.

  14. Learning Windows Azure Mobile Services for Windows 8 and Windows Phone 8

    CERN Document Server

    Webber-Cross, Geoff

    2014-01-01

    This book is based around a case study game which was written for the book. This means that the chapters progress in a logical way and build upon lessons learned as we go. Real-world examples are provided for each topic that are practical and not given out-of-context so they can be applied directly to other applications.If you are a developer who wishes to build Windows 8 and Phone 8 applications and integrate them with Windows Azure Mobile Services, this book is for you. Basic C# and JavaScript skills are advantageous, as well as some knowledge of building Windows 8 or Windows Phone 8 applica

  15. Functional characteristics, wettability properties and cytotoxic effect of starch film incorporated with multi-walled and hydroxylated multi-walled carbon nanotubes.

    Science.gov (United States)

    Shahbazi, Mahdiyar; Rajabzadeh, Ghadir; Sotoodeh, Shahnaz

    2017-11-01

    Two types of multi-walled carbon nanotubes (CNT and CNT-OH) at different levels (0.1-0.9wt%) were introduced into starch matrix in order to modify its functional properties. The optimum concentration of each nanotube was selected based on the results of water solubility, water permeability and mechanical experiments. The physico-mechanical data showed that CNT up to 0.7wt% led to a notable increase in water resistance, water barrier property and tensile strength, whilst regarding CNT-OH, these improvements found at 0.9wt%. Therefore, effects of optimized level of each nanotube on the starch film were evaluated by XRD, surface hydrophobicity, wettability and surface energy tests. XRD revealed that the position of starch characteristic peak shifted to higher degree after nanotubes introducing. The hydrophobic character of the film was greatly increased with incorporation of nanoparticles, as evidenced by increased contact angle with greatest value regarding CNT-OH. Moreover, CNT-OH notably decreased the surface free energy of the starch film. Finally, the conformity of both nanocomposites with actual food regulations on biodegradable materials was tested by cytotoxicity assay to evaluate the possibility of application in food packaging sector. Both nanocomposite films had potential of cytotoxic effects, since they could increase cytoplasmic lactate dehydrogenase release from L-929 fibroblast cells in contact with their surface. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Multi Channels PWM Controller for Thermoelectric Cooler Using a Programmable Logic Device and Lab-Windows CVI

    Directory of Open Access Journals (Sweden)

    Eli FLAXER

    2008-09-01

    Full Text Available We present a complete design of a multi channels PID controller for Thermoelectric Cooler (TEC using a pulse width modulation (PWM technique implemented by a dedicated programmable logic device (PLD programmed by VHDL. The PID control loop is implemented by software written by National Instrument Lab-Windows CVI. Due to the fact that the implementation is by a VHDL and PLD the design is modular, as a result, the circuit is very compact in size and very low cost as compared to any commercial product. In addition, since the control loop is implemented by software running on a personal computer (PC using a C language, it is easy to adjust the controller to various environmental conditions and for a width range of sensors like: a thermo couple (TC, thermistor, resistance temperature detectors (RTD etc. We demonstrate the performance of this circuit as a controller for a small incubator using thermistor as the temperature sensor.

  17. The Effect of Multi Wall Carbon Nanotubes on Some Physical Properties of Epoxy Matrix

    Science.gov (United States)

    Al-Saadi, Tagreed M.; hammed Aleabi, Suad; Al-Obodi, Entisar E.; Abdul-Jabbar Abbas, Hadeel

    2018-05-01

    This research involves using epoxy resin as a matrix for making a composite material, while the multi wall carbon nanotubes (MWNCTs) is used as a reinforcing material with different fractions (0.0,0.02, 0.04, 0.06) of the matrix weight. The mechanical ( hardness ), electrical ( dielectric constant, dielectric loss factor, dielectric strength, electrical conductivity ), and thermal properties (thermal conductivity ) were studied. The results showed the increase of hardness, thermal conductivity, electrical conductivity and break down strength with the increase of MWCNT concentration, but the behavior of dielectric loss factor and dielectric constant is opposite that.

  18. Highly Insulating Windows with a U-value less than 0.6 W/m2K

    Energy Technology Data Exchange (ETDEWEB)

    Wendell Rhine; Ying Tang; Wenting Dong; Roxana Trifu; Reduane Begag

    2008-11-30

    satisfying constraints such as durability, cost, user acceptance, size limits, and environmental safety concerns. The energy efficient daylighting window will consist of a translucent and resilient aerogel panel sandwiched between glass panes in double glazed windows. Compared to the best windows available today, the double glazed translucent windows with 1/2-inch aerogel inserts will have a U-value of 1.2 W/m{sup 2} K (0.211 BTU/ft{sup 2} h F) without any coating or low conductivity fill gases. These windows will be more effective than the windows with an Energy Star rating of U-2 W/m{sup 2} K and could be made even more efficient by using low-e coated glass glazings and inert gas fills. This report summarizes the work accomplished on Cooperative Agreement DE-FC26-03NT41950. During this project, Aspen Aerogels made transparent and translucent aerogels from TMOS and TEOS. We characterized the transparency of the aerogels, reinforced the transparent aerogels with fibers and prepared large translucent aerogel panels and blankets. We also conducted an initial market study for energy efficient translucent windows. A lab-scale process was developed that could be scaled-up to manufacture blankets of these translucent aerogels. The large blankets prepared were used to fabricate prototype translucent windows and skylights. The primary goal of this project was to develop transparent, resilient, hydrophobic silica aerogels that have low thermal conductivities (R-10/inch) to be used to produce aerogel insulated double-glazing windows with a U value of 0.6 W/m{sup 2}K. To meet this objective we developed a process and equipment to produce blankets of translucent, hydrophobic aerogel. We focused on silica, organically-modified silica aerogels (Ormosils), and fiber reinforced silica aerogels due to the appreciable expertise in silica sol-gel processing available with the personnel at Aspen Aerogels, and also due to the quantity of knowledge available in the scientific literature. The

  19. LIFE Materials: Topical Assessment Report for LIFE Volume 1 TOPIC: Solid First Wall and Structural Components TASK: Radiation Effects on First Wall

    Energy Technology Data Exchange (ETDEWEB)

    Caro, A

    2008-11-26

    This report consists of the following chapters: CHAPTER A: LIFE Requirements for Materials. Part 1: The structure of the First Wall--Basic requirements; A qualitative view of the challenge; The candidate materials; and Base-line material's properties. CHAPTER B: Summary of Existing Knowledge--Brief historical introduction; Design window; The temperature window; Evolution of the design window with damage; Damage calculations; He and H production; Swelling resistance; Incubation dose for swelling; Design criterion No. 1, Strength; Design criterion No. 2, Corrosion resistance; Design criterion No. 3, Creep resistance; Design criterion No. 4, Radiation induced embrittlement; and Conclusions. CHAPTER C: Identification of Gaps in Knowledge & Vulnerabilities. CHAPTER D: Strategy and Future Work.

  20. Multi-wall carbon nanotubes investigated by positron annihilation techniques and microscopies for further production handling

    Energy Technology Data Exchange (ETDEWEB)

    Luu, A.T.; Thanh, N.D.; Dung, T.Q.; Son, L.T.; Phuc, P.T. [Center for Nuclear Techniques, Vietnam Atomic Energy Commission, Ho Chi Minh City (Viet Nam); Kajcsos, Zs. [KFKI Research Institute for Particle and Nuclear Physics, Budapest (Hungary); Nhon, M.V.; Tap, T.D. [Department of Nuclear Physics, Faculty of Physics, University of Natural Sciences, Ho Chi Minh City (Viet Nam); Lazar, K. [Institute of Isotopes HAS, Budapest (Hungary); Havancsak, K.; Huhn, G. [Department of Materials Physics, Budapest Univ. (Hungary); Horvath, Z.E. [Research Institute for Technical Physics and Materials Sciences, Budapest (Hungary)

    2009-11-15

    Multi-wall carbon nanotube samples with various tube diameters produced by Thermal Chemical Vapor Deposition technique using various catalysts were studied by various microscopic methods and positron annihilation spectroscopy (PAS) with the aim of assessing the applicability of these methods for structural studies in these novel materials. Specifically, positron lifetime (LT) and Doppler broadening (DB) techniques, transmission electron microscopy (TEM) and atomic force microscopy (AFM) were employed, on iron-containing samples Moessbauer spectroscopy was also utilized. The PAS measurements were carried out on densely packed powder samples and on samples pressed into pills in atmospheric pressure and in vacuum as well. The lifetime values could be interpreted by assuming trapping of positrons, the low contribution from longer-living trapped positronium can be probably related to defects on walls of the tubes. Possibility of correlation of LT and DB data with the nanotube sizes and sample composition was also considered. (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  1. Fabrication and characterization of ZnO-coated multi-walled carbon nanotubes with enhanced photocatalytic activity

    International Nuclear Information System (INIS)

    Jiang Linqin; Gao Lian

    2005-01-01

    Through noncovalent modification of multi-walled carbon nanotubes (MWNTs) with the dispersant of sodium dodecyl sulfate (SDS), ZnO nanocrystals-coated MWNTs composite was fabricated. The electrostatic interaction mechanism is used to illustrate the formation of ZnO/MWNTs nanocomposite. The ZnO-coated MWNTs composite shows a small blue-shift absorption compared with pure ZnO nanomaterial and preserves the electronic energy states of MWNTs. The photocatalytic experiments exhibit that this composite has a higher photocatalytic activity than ZnO bulk material or the mechanical mixture of MWNTs and ZnO

  2. Effect of doping of multi-walled carbon nanotubes on phenolic based carbon fiber reinforced nanocomposites

    International Nuclear Information System (INIS)

    Saeed, Sadaf; Hakeem, Saira; Faheem, Muhammad; Alvi, Rashid Ahmed; Farooq, Khawar; Hussain, Syed Tajammul; Ahmad, Shahid Nisar

    2013-01-01

    We report on the effect of multi-walled carbon nanotubes (MWCNTs) on different properties of phenolic resin. A low content of MWCNTs (∼ 0.05 wt%) was mixed in phenolic resin and a stable dispersion was achieved by ultrasonication, followed by melt mixing. After curing the characterization of these composites was done by using scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and Fourier transform infra-red spectroscopy (FTIR). The thermal and ablative properties of carbon fiber reinforced MWCNTs-phenolic nanocomposites were also studied. The addition of MWCNTs showed improvement in thermal stability and ablation properties.

  3. Removal of Malachite Green Dye from Aqueous Solution Using Multi-Walled Carbon Nano tubes: An Application of Experimental Design

    International Nuclear Information System (INIS)

    Siti Aminah Zulkepli; Md Pauzi Abdullah; Md Pauzi Abdullah; Wan Mohd Afiq Wan Mohd Khalik

    2016-01-01

    An experimental design methodology was performed in the optimization of removal of malachite green dye by multi-walled carbon nano tubes. A Central Composite Design (25) was chosen to develop a mathematical model and determine the optimum condition for adsorption of malachite green by carbon nano tubes. Five experimental factors, namely initial dye concentration, mass of adsorbent, pH, contact time and agitation speed were studied. Maximum adsorption of malachite green was achieved at the suggested optimum conditions: initial dye concentration (20 ppm), weight of adsorbent (0.03 g), pH solution (7) contact time (17 min) and agitation speed (150 strokes per min). The experimental value of adsorption by multi-walled carbon nano tubes were found to be in good agreement with the predicted value (R"2 = 0.922).The experimental equilibrium data were best fitted to isotherm model (Langmuir) and kinetic model (pseudo second-order) respectively. Maximum adsorption by carbon nano tubes at monolayer for malachite green was obtained at 112.36 mg/ g while kinetic rate constant was calculated to be 0.0017 g mg"-"1 min"-"1. (author)

  4. Dispersion of multi-walled carbon nanotubes in biocompatible dispersants

    International Nuclear Information System (INIS)

    Piret, J.-P.; Detriche, S.; Vigneron, R.; Vankoningsloo, S.; Rolin, S.; Mejia Mendoza, J. H.; Masereel, B.; Lucas, S.; Delhalle, J.; Luizi, F.; Saout, C.; Toussaint, O.

    2010-01-01

    Owing to their phenomenal electrical and mechanical properties, carbon nanotubes (CNT) have been an area of intense research since their discovery in 1991. Different applications for these nanoparticles have been proposed, among others, in electronics and optics but also in the medical field. In parallel, emerging studies have suggested potential toxic effects of CNT while others did not, generating some conflicting outcomes. These discrepancies could be, in part, due to different suspension approaches used and to the agglomeration state of CNT in solution. In this study, we described a standardized protocol to obtain stable CNT suspensions, using two biocompatible dispersants (Pluronic F108 and hydroxypropylcellulose) and to estimate the concentration of CNT in solution. CNT appear to be greatly individualized in these two dispersants with no detection of remaining bundles or agglomerates after sonication and centrifugation. Moreover, CNT remained perfectly dispersed when added to culture medium used for in vitro cell experiments. We also showed that Pluronic F108 is a better dispersant than hydroxypropylcellulose. In conclusion, we have developed a standardized protocol using biocompatible surfactants to obtain reproducible and stable multi-walled carbon nanotubes suspensions which can be used for in vitro or in vivo toxicological studies.

  5. A generalized window energy rating system for typical office buildings

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Cheng; Chen, Tingyao; Yang, Hongxing; Chung, Tse-ming [Research Center for Building Environmental Engineering, Department of Building Services Engineering, The Hong Kong Polytechnic University, Hong Kong (China)

    2010-07-15

    Detailed computer simulation programs require lengthy inputs, and cannot directly provide an insight to relationship between the window energy performance and the key window design parameters. Hence, several window energy rating systems (WERS) for residential houses and small buildings have been developed in different countries. Many studies showed that utilization of daylight through elaborate design and operation of windows leads to significant energy savings in both cooling and lighting in office buildings. However, the current WERSs do not consider daylighting effect, while most of daylighting analyses do not take into account the influence of convective and infiltration heat gains. Therefore, a generalized WERS for typical office buildings has been presented, which takes all primary influence factors into account. The model includes embodied and operation energy uses and savings by a window to fully reflect interactions among the influence parameters. Reference locations selected for artificial lighting and glare control in the current common simulation practice may cause uncompromised conflicts, which could result in over- or under-estimated energy performance. Widely used computer programs, DOE2 and ADELINE, for hourly daylighting and cooling simulations have their own weaknesses, which may result in unrealistic or inaccurate results. An approach is also presented for taking the advantages of the both programs and avoiding their weaknesses. The model and approach have been applied to a typical office building of Hong Kong as an example to demonstrate how a WERS in a particular location can be established and how well the model can work. The energy effect of window properties, window-to-wall ratio (WWR), building orientation and lighting control strategies have been analyzed, and can be indicated by the localized WERS. An application example also demonstrates that the algebraic WERS derived from simulation results can be easily used for the optimal design of

  6. Feelings of Loss in Response to Divorce: Assessment and Intervention.

    Science.gov (United States)

    Huber, Charles H.

    1983-01-01

    Presents a cognitively based model, founded on rational emotive therapy, as a basis for assessment and intervention strategies for assisting individuals to cope with feelings of loss in response to divorce. The model is seen as a four-pane window through which persons might see their divorce. (Author/JAC)

  7. Skin effect mitigation in laser processed multi-walled carbon nanotube/copper conductors

    Science.gov (United States)

    Keramatnejad, K.; Zhou, Y. S.; Gao, Y.; Rabiee Golgir, H.; Wang, M.; Jiang, L.; Silvain, J.-F.; Lu, Y. F.

    2015-10-01

    In this study, laser-processed multi-walled carbon nanotube (MWCNT)/Cu conductors are introduced as potential passive components to mitigate the skin effect of Cu at high frequencies (0-10 MHz). Suppressed skin effect is observed in the MWCNT/Cu conductors compared to primitive Cu. At an AC frequency of 10 MHz, a maximum AC resistance reduction of 94% was observed in a MWCNT/Cu conductor after being irradiated at a laser power density of 189 W/cm2. The reduced skin effect in the MWCNT/Cu conductors is ascribed to the presence of MWCNT channels which are insensitive to AC frequencies. The laser irradiation process is observed to play a crucial role in reducing contact resistance at the MWCNT-Cu interfaces, removing impurities in MWCNTs, and densifying MWCNT films.

  8. Skin effect mitigation in laser processed multi-walled carbon nanotube/copper conductors

    Energy Technology Data Exchange (ETDEWEB)

    Keramatnejad, K.; Zhou, Y. S.; Gao, Y.; Rabiee Golgir, H.; Wang, M.; Lu, Y. F., E-mail: ylu2@unl.edu [Department of Electrical and Computer Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska 68588-0511 (United States); Jiang, L. [School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081 (China); Silvain, J.-F. [Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB-CNRS) 87, Avenue du Docteur Albert Schweitzer F-33608 Pessac Cedex (France)

    2015-10-21

    In this study, laser-processed multi-walled carbon nanotube (MWCNT)/Cu conductors are introduced as potential passive components to mitigate the skin effect of Cu at high frequencies (0–10 MHz). Suppressed skin effect is observed in the MWCNT/Cu conductors compared to primitive Cu. At an AC frequency of 10 MHz, a maximum AC resistance reduction of 94% was observed in a MWCNT/Cu conductor after being irradiated at a laser power density of 189 W/cm{sup 2}. The reduced skin effect in the MWCNT/Cu conductors is ascribed to the presence of MWCNT channels which are insensitive to AC frequencies. The laser irradiation process is observed to play a crucial role in reducing contact resistance at the MWCNT-Cu interfaces, removing impurities in MWCNTs, and densifying MWCNT films.

  9. Skin effect mitigation in laser processed multi-walled carbon nanotube/copper conductors

    International Nuclear Information System (INIS)

    Keramatnejad, K.; Zhou, Y. S.; Gao, Y.; Rabiee Golgir, H.; Wang, M.; Lu, Y. F.; Jiang, L.; Silvain, J.-F.

    2015-01-01

    In this study, laser-processed multi-walled carbon nanotube (MWCNT)/Cu conductors are introduced as potential passive components to mitigate the skin effect of Cu at high frequencies (0–10 MHz). Suppressed skin effect is observed in the MWCNT/Cu conductors compared to primitive Cu. At an AC frequency of 10 MHz, a maximum AC resistance reduction of 94% was observed in a MWCNT/Cu conductor after being irradiated at a laser power density of 189 W/cm 2 . The reduced skin effect in the MWCNT/Cu conductors is ascribed to the presence of MWCNT channels which are insensitive to AC frequencies. The laser irradiation process is observed to play a crucial role in reducing contact resistance at the MWCNT-Cu interfaces, removing impurities in MWCNTs, and densifying MWCNT films

  10. Poly(vinyl chloride-grafted multi-walled carbon nanotubes via Friedel-Crafts alkylation

    Directory of Open Access Journals (Sweden)

    2010-11-01

    Full Text Available A novel approach was developed for the surface modification of the multi-walled carbon nanotubes (MWCNTs with high percentage of grafting (PG% by the grafting of polymer via the Friedel-Crafts alkylation. The graft reaction conditions, such as the amount of catalyst added, the reaction temperature, and the reaction time were optimized for the Friedel-Crafts alkylation of the MWCNTs with poly(vinyl chloride (PVC with anhydrous aluminum chloride (AlCl3 as catalyst in chloroform (CHCl3. The Fourier Transform Infrared (FT-IR, Raman, and thermogravimetric (TGA analysis showed that PVC had been successfully grafted onto MWCNTs both at the ends and on the sidewalls by the proposed Friedel-Crafts alkylation. The PVC grafted MWCNTs (PVC-MWCNTs could be dispersed well in organic solvent and the dispersion was more stable.

  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

    2013-04-01

    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. Windows server cookbook for Windows server 2003 and Windows 2000

    CERN Document Server

    Allen, Robbie

    2005-01-01

    This practical reference guide offers hundreds of useful tasks for managing Windows 2000 and Windows Server 2003, Microsoft's latest server. These concise, on-the-job solutions to common problems are certain to save you many hours of time searching through Microsoft documentation. Topics include files, event logs, security, DHCP, DNS, backup/restore, and more

  13. Analysis of a grid window structure for RF cavities in a Muon cooling channel

    International Nuclear Information System (INIS)

    Ladran, A.; Li, D.; Moretti, A.; Rimmer, R.; Staples, J.; Virostek, S.; Zisman, M.

    2003-01-01

    We report on the electromagnetic and thermal analysis of a grid window structure for high gradient, low frequency RF cavities. Windows may be utilized to close the beam iris and increase shunt impedance of closed-cell RF cavities. This work complements previous work presented for windows made of solid beryllium foil. An electromagnetic and thermal analysis of the thin wall tubes in a grid pattern was conducted using both MAFIA4 and ANSYS finite element analyses. The results from both codes agreed well for a variety of grid configurations and spacing. The grid configuration where the crossing tubes touched was found to have acceptable E-Fields and H-Fields performance. The thermal profiles for the grid will also be shown to determine a viable cooling profile

  14. Hydrogen storage behaviors of platinum-supported multi-walled carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Park, Soo-Jin; Lee, Seul-Yi [Department of Chemistry, Inha University, 253 Nam-gu, Incheon 402-751 (Korea, Republic of)

    2010-12-15

    In this work, the hydrogen storage behaviors of multi-walled carbon nanotubes (MWNTs) loaded by crystalline platinum (Pt) particles were studied. The microstructure of the Pt/MWNTs was characterized by X-ray diffraction and transmission electron microscopy. The pore structure and total pore volumes of the Pt/MWNTs were analyzed by N{sub 2}/77 K adsorption isotherms. The hydrogen storage capacity of the Pt/MWNTs was evaluated at 298 K and 100 bar. From the experimental results, it was found that Pt particles were homogeneously distributed on the MWNT surfaces. The amount of hydrogen storage capacity increased in proportion to the Pt content, with Pt-5/MWNTs exhibiting the largest hydrogen storage capacity. The superior amount of hydrogen storage was linked to an increase in the number of active sites and the optimum-controlled micropore volume for hydrogen adsorption due to the well-dispersed Pt particles. Therefore, it can be concluded that Pt particles play an important role in hydrogen storage characteristics due to the hydrogen spillover effect. (author)

  15. Plasma Treated Multi-Walled Carbon Nanotubes (MWCNTs for Epoxy Nanocomposites

    Directory of Open Access Journals (Sweden)

    Jie Lian

    2011-12-01

    Full Text Available Plasma nanocoating of allylamine were deposited on the surfaces of multi-walled carbon nanotubes (MWCNTs to provide desirable functionalities and thus to tailor the surface characteristics of MWCNTs for improved dispersion and interfacial adhesion in epoxy matrices. Plasma nanocoated MWCNTs were characterized using scanning electron microscopy (SEM, high-resolution transmission electron microscopy (HR-TEM, surface contact angle, and pH change measurements. Mechanical testing results showed that epoxy reinforced with 1.0 wt % plasma coated MWCNTs increased the tensile strength by 54% as compared with the pure epoxy control, while epoxy reinforced with untreated MWCNTs have lower tensile strength than the pure epoxy control. Optical and electron microscopic images show enhanced dispersion of plasma coated MWCNTs in epoxy compared to untreated MWCNTs. Plasma nanocoatings from allylamine on MWCNTs could significantly enhance their dispersion and interfacial adhesion in epoxy matrices. Simulation results based on the shear-lag model derived from micromechanics also confirmed that plasma nanocoating on MWCNTs significantly improved the epoxy/fillers interface bonding and as a result the increased composite strength.

  16. Graphene versus Multi-Walled Carbon Nanotubes for Electrochemical Glucose Biosensing

    Directory of Open Access Journals (Sweden)

    Edmond Lam

    2013-03-01

    Full Text Available : A simple procedure was developed for the fabrication of electrochemical glucose biosensors using glucose oxidase (GOx, with graphene or multi-walled carbon nanotubes (MWCNTs. Graphene and MWCNTs were dispersed in 0.25% 3-aminopropyltriethoxysilane (APTES and drop cast on 1% KOH-pre-treated glassy carbon electrodes (GCEs. The EDC (1-ethyl-(3-dimethylaminopropyl carbodiimide-activated GOx was then bound covalently on the graphene- or MWCNT-modified GCE. Both the graphene- and MWCNT-based biosensors detected the entire pathophysiological range of blood glucose in humans, 1.4–27.9 mM. However, the direct electron transfer (DET between GOx and the modified GCE’s surface was only observed for the MWCNT-based biosensor. The MWCNT-based glucose biosensor also provided over a four-fold higher current signal than its graphene counterpart. Several interfering substances, including drug metabolites, provoked negligible interference at pathological levels for both the MWCNT- and graphene-based biosensors. However, the former was more prone to interfering substances and drug metabolites at extremely pathological concentrations than its graphene counterpart.

  17. Graphene versus Multi-Walled Carbon Nanotubes for Electrochemical Glucose Biosensing.

    Science.gov (United States)

    Zheng, Dan; Vashist, Sandeep Kumar; Dykas, Michal Marcin; Saha, Surajit; Al-Rubeaan, Khalid; Lam, Edmond; Luong, John H T; Sheu, Fwu-Shan

    2013-03-14

    : A simple procedure was developed for the fabrication of electrochemical glucose biosensors using glucose oxidase (GOx), with graphene or multi-walled carbon nanotubes (MWCNTs). Graphene and MWCNTs were dispersed in 0.25% 3-aminopropyltriethoxysilane (APTES) and drop cast on 1% KOH-pre-treated glassy carbon electrodes (GCEs). The EDC (1-ethyl-(3-dimethylaminopropyl) carbodiimide)-activated GOx was then bound covalently on the graphene- or MWCNT-modified GCE. Both the graphene- and MWCNT-based biosensors detected the entire pathophysiological range of blood glucose in humans, 1.4-27.9 mM. However, the direct electron transfer (DET) between GOx and the modified GCE's surface was only observed for the MWCNT-based biosensor. The MWCNT-based glucose biosensor also provided over a four-fold higher current signal than its graphene counterpart. Several interfering substances, including drug metabolites, provoked negligible interference at pathological levels for both the MWCNT- and graphene-based biosensors. However, the former was more prone to interfering substances and drug metabolites at extremely pathological concentrations than its graphene counterpart.

  18. Milling and dispersion of multi-walled carbon nanotubes in texanol

    Science.gov (United States)

    Darsono, Nono; Yoon, Dang-Hyok; Kim, Jaemyung

    2008-03-01

    Rheological results were used to determine the optimum type of dispersant and its concentration for six commercial dispersants for the dispersion of multi-walled carbon nanotube (MWCNT) agglomerates in texanol. An unsaturated polycarboxylic acid copolymer (BYK P-104) exhibited the optimum performance with the lowest MWCNT slurry viscosity in texanol. The cutting and dispersion efficiencies of MWCNTs with 20 wt.% of BYK P-104 dispersant were compared using conventional ball milling and high energy milling, whereby the latter was found to be more effective. High energy milling for 2 h produced a large portion of MWCNT agglomerates smaller than 150 nm, showing a drastic increase in slurry viscosity due to the dispersion into individual CNTs. On the other hand, 120 h ball milling was required to achieve the agglomerate size of 300 nm with less viscosity increase upon milling. Decrease in the degree of MWCNT crystallinity was observed by both milling, even though 2 h high energy milling showed slightly less damage than 120 h ball milling based on XRD and Raman spectroscopy results.

  19. The Design and Simulation of Natural Personalised Ventilation (NPV System for Multi-Bed Hospital Wards

    Directory of Open Access Journals (Sweden)

    Zulfikar A. Adamu

    2015-05-01

    Full Text Available Adequate ventilation is necessary for thermal comfort and reducing risks from infectious bio-aerosols in hospital wards, but achieving this with mechanical ventilation has carbon and energy implications. Natural ventilation is often limited to window-based designs whose dilution/mixing effectiveness are subject to constraints of wind speed, cross ventilation, and in the case of hospital wards, proximity of patients to external walls. A buoyancy-driven natural ventilation system capable of achieving dilution/mixing was shown to be feasible in a preceding study of novel system called natural personalised ventilation (NPV. This system combined both architecture and airflow engineering principles of space design and buoyancy and was tested and validated (salt-bath experiment for a single bed ward. This research extends the previous work and is proof-of-concept on the feasibility of NPV system for multi-bed wards. Two different four-bed ward types were investigated of using computational fluid dynamics (CFD simulations under wind-neutral conditions. Results predict that NPV system could deliver fresh air to multiple patients, including those located 10 m away from external wall, with absolute flow rates of between 32 L·s−1 and 54 L·s−1 for each patient/bed. Compared to same wards simulated using window design, ingress of airborne contaminants into patients’ breathing zone and summer overheating potential were minimised, while overall ward dilution was maximised. Findings suggest the NPV has potentials for enabling architects and building service engineers to decouple airflow delivery from the visualisation and illumination responsibilities placed upon windows.

  20. MS Windows domēna darbstaciju migrācija no MS Windows XP uz Windows Vista.

    OpenAIRE

    Tetere, Agate

    2009-01-01

    Kvalifikācijas darbā izpētīju darbstaciju migrācijas no Windows XP uz Windows Vista plusus un mīnusus. Darba gaitā tika veikti sekojoši uzdevumi: 1.Veikta Windows XP un Windows Vista darbstaciju instalācija, iestatījumu konfigurēšana un tika pārbaudīta sistēmas darbība 2.Veikta Windows Server 2003 un Windows Server 2008 instalācija, iestatījumu konfigurēšana un tika pārbaudīta sistēmas darbība 3.Izstrādāts migrācijas modelis 4.Veikta migrācijas optimizēšana 5.Veikta datu migrāc...

  1. Evaluation of Cardiopulmonary Toxicity Following Oral Administration of Multi-walled Carbon Nanotubes in Wistar Rats

    Directory of Open Access Journals (Sweden)

    Ehsan Zayerzadeh

    2016-07-01

    Full Text Available Objective(s: Carbon nanotubes have unique mechanical, electrical, and thermal properties, with potential different applications in nanomedicine, electronics, and other industries. These new applications of carbon nanotubes in different industries lead to the increased exposure risk of nanomaterials to human. Up to now, all aspects of carbon nanotubes toxicity are not completely clear following human and animal exposures with these novel compounds. The aim of this study was to assess cardiopulmonary toxicity of multi-walled carbon nanotubes following oral administration in rats with respect to the histopathological and biochemical evaluation. Methods: In the present investigation, we studied cardiorespiratory toxicity of multi-wall carbon nanotubes (MWCNT with regard to histopathological changes and some biomarkers including TnT, CK-MB and LDH in experimental rats following oral administration. One dose per 24 h of MWCNT suspension was administered orally (gavage technique to animals at the doses of 500, 1000 and 2000 mg/kg/day BW for 5 days. Results: The results of these study showed oral administration of MWCNT induces histopathological complications such as severe alveolar edema and hemorrhage in lungs and myocytolysis in heart of all experimental groups of animals. In all of the groups, troponin T level showed no changes when compared to baseline. Lactate dehydrogenase and CK-MB activity showed significant increment in all of animal groups following oral administration of carbon nanotubes. Conclusions: It can be concluded that oral exposure of MWCNT may be toxic for cardiovascular and respiratory systems, because MWCNT induced biochemical alterations and histopathological abnormalities in these vital systems.

  2. Grab Windows training opportunities; check CERN Windows roadmap!

    CERN Multimedia

    IT Department

    2011-01-01

    CERN Operating Systems and Information Services group (IT-OIS) actively monitors market trends to check how new software products correspond to CERN needs. In the Windows world, Windows 7 has been a big hit, with over 1500 Windows 7 PCs within less than a year since its support was introduced at CERN. No wonder: Windows XP is nearly 10 years old and is steadily approaching the end of its life-cycle. At CERN, support for Windows XP will stop at the end of December 2012. Compared to Vista, Windows 7 has the same basic hardware requirements, but offers higher performance, so the decision to upgrade is rather straightforward. CERN support for Vista will end in June 2011. In the world of Microsoft Office, version 2007 offers better integration with the central services than the older version 2003. Progressive upgrade from 2003 to 2007 is planned to finish in September 2011, but users are encouraged to pro-actively upgrade at their convenience. Please note that Office 2007 brings an important change in the area of ...

  3. Solid-contact pH-selective electrode using multi-walled carbon nanotubes.

    Science.gov (United States)

    Crespo, Gastón A; Gugsa, Derese; Macho, Santiago; Rius, F Xavier

    2009-12-01

    Multi-walled carbon nanotubes (MWCNT) are shown to be efficient transducers of the ionic-to-electronic current. This enables the development of a new solid-contact pH-selective electrode that is based on the deposition of a 35-microm thick layer of MWCNT between the acrylic ion-selective membrane and the glassy carbon rod used as the electrical conductor. The ion-selective membrane was prepared by incorporating tridodecylamine as the ionophore, potassium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate as the lipophilic additive in a polymerized methylmethacrylate and an n-butyl acrylate matrix. The potentiometric response shows Nernstian behaviour and a linear dynamic range between 2.89 and 9.90 pH values. The response time for this electrode was less than 10 s throughout the whole working range. The electrode shows a high selectivity towards interfering ions. Electrochemical impedance spectroscopy and chronopotentiometry techniques were used to characterise the electrochemical behaviour and the stability of the carbon-nanotube-based ion-selective electrodes.

  4. Aligned multi-walled carbon nanotube-reinforced composites: processing and mechanical characterization

    International Nuclear Information System (INIS)

    Thostenson, Erik T.; Chou, Tsuwei

    2002-01-01

    Carbon nanotubes have been the subject of considerable attention because of their exceptional physical and mechanical properties. These properties observed at the nanoscale have motivated researchers to utilize carbon nanotubes as reinforcement in composite materials. In this research, a micro-scale twin-screw extruder was used to achieve dispersion of multi-walled carbon nanotubes in a polystyrene matrix. Highly aligned nanocomposite films were produced by extruding the polymer melt through a rectangular die and drawing the film prior to cooling. Randomly oriented nanocomposites were produced by achieving dispersion first with the twin-screw extruder followed by pressing a film using a hydraulic press. The tensile behaviour of the aligned and random nanocomposite films with 5 wt.{%} loading of nanotubes were characterized. Addition of nanotubes increased the tensile modulus, yield strength and ultimate strengths of the polymer films, and the improvement in elastic modulus with the aligned nanotube composite is five times greater than the improvement for the randomly oriented composite. (author)

  5. Infrared and microwave properties of polypyrrole/multi-walled carbon nanotube composites

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Qi; Wang, Yongsheng, E-mail: yshwang@bjtu.edu.cn; He, Dawei, E-mail: dwhe@bjtu.edu.cn; Gao, Lei; Zhou, Yikang; Fu, Ming

    2014-08-01

    This study analyses the formation of polypyrrole/multi-walled carbon nanotube (PPy/MWCNT) composite materials using chemical oxidation with varying amounts of MWCNTs added. The samples are characterized by scanning electron microscopy, Fourier transform infrared emission spectroscopy, a four-probe method, and infrared thermal imaging using electromagnetic parameters. According to the test results, it is seen that the formation of PPy with the addition of MWCNTs can affect the material’s infrared properties and increase the material’s microwave return losses (up to −19 dB). This production procedure can also make the peak frequency of the microwave return losses adjustable, and the composite’s infrared and microwave performance becomes compatible and adjustable. - Highlights: • A one step in-situ synthesis method of PPy/MWCNT polymerization is proposed. • The composites were used for infrared camouflage and for their microwave properties. • The microwave return losses and infrared emissivity of the composites are adjustable. • The mechanism relies on changes in the composites’ conductivity.

  6. Infrared and microwave properties of polypyrrole/multi-walled carbon nanotube composites

    International Nuclear Information System (INIS)

    Gao, Qi; Wang, Yongsheng; He, Dawei; Gao, Lei; Zhou, Yikang; Fu, Ming

    2014-01-01

    This study analyses the formation of polypyrrole/multi-walled carbon nanotube (PPy/MWCNT) composite materials using chemical oxidation with varying amounts of MWCNTs added. The samples are characterized by scanning electron microscopy, Fourier transform infrared emission spectroscopy, a four-probe method, and infrared thermal imaging using electromagnetic parameters. According to the test results, it is seen that the formation of PPy with the addition of MWCNTs can affect the material’s infrared properties and increase the material’s microwave return losses (up to −19 dB). This production procedure can also make the peak frequency of the microwave return losses adjustable, and the composite’s infrared and microwave performance becomes compatible and adjustable. - Highlights: • A one step in-situ synthesis method of PPy/MWCNT polymerization is proposed. • The composites were used for infrared camouflage and for their microwave properties. • The microwave return losses and infrared emissivity of the composites are adjustable. • The mechanism relies on changes in the composites’ conductivity

  7. A new method synthesis polyaniline/multi-walled carbon nanotube composites for supercapacitor electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Pan, J.; Wei, X.; Zhou, S.P. [Shandong Univ. of Technology, Zibo (China). School of Chemical Engineering

    2010-07-01

    A series of polyaniline multi-walled nanotube (PANIMWNT) composite films were prepared using an in situ polymerization technique. Scanning electron microscopy (SEM) was used to characterize the morphology and microstructure of the samples. Cyclic voltammetry (CV), impedance spectroscopy, and galvanostatic charge/discharge analyses were used to determine the electrochemical properties of the PANIMWNT films in a 3-electrode system. The electrochemical performance of PANI, PANIMWNT, and MWNT film performances was then compared. Results of the study showed that the PANI electrodes showed a much higher capacitance than the MWNT and PANIMWNT electrodes. Both the PANI and PANIMWNT nanocomposites showed good electrochemical capacitance. The improved performance of the electrodes was attributed to the presence of sodium hypochlorite (NaClO). 5 refs.

  8. Breakdown voltage reduction by field emission in multi-walled carbon nanotubes based ionization gas sensor

    Energy Technology Data Exchange (ETDEWEB)

    Saheed, M. Shuaib M.; Muti Mohamed, Norani; Arif Burhanudin, Zainal, E-mail: zainabh@petronas.com.my [Centre of Innovative Nanostructures and Nanodevices, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, 31750 Tronoh, Perak (Malaysia)

    2014-03-24

    Ionization gas sensors using vertically aligned multi-wall carbon nanotubes (MWCNT) are demonstrated. The sharp tips of the nanotubes generate large non-uniform electric fields at relatively low applied voltage. The enhancement of the electric field results in field emission of electrons that dominates the breakdown mechanism in gas sensor with gap spacing below 14 μm. More than 90% reduction in breakdown voltage is observed for sensors with MWCNT and 7 μm gap spacing. Transition of breakdown mechanism, dominated by avalanche electrons to field emission electrons, as decreasing gap spacing is also observed and discussed.

  9. Control of neuronal network organization by chemical surface functionalization of multi-walled carbon nanotube arrays

    International Nuclear Information System (INIS)

    Liu Jie; Bibari, Olivier; Marchand, Gilles; Benabid, Alim-Louis; Sauter-Starace, Fabien; Appaix, Florence; De Waard, Michel

    2011-01-01

    Carbon nanotube substrates are promising candidates for biological applications and devices. Interfacing of these carbon nanotubes with neurons can be controlled by chemical modifications. In this study, we investigated how chemical surface functionalization of multi-walled carbon nanotube arrays (MWNT-A) influences neuronal adhesion and network organization. Functionalization of MWNT-A dramatically modifies the length of neurite fascicles, cluster inter-connection success rate, and the percentage of neurites that escape from the clusters. We propose that chemical functionalization represents a method of choice for developing applications in which neuronal patterning on MWNT-A substrates is required.

  10. Control of neuronal network organization by chemical surface functionalization of multi-walled carbon nanotube arrays

    Energy Technology Data Exchange (ETDEWEB)

    Liu Jie; Bibari, Olivier; Marchand, Gilles; Benabid, Alim-Louis; Sauter-Starace, Fabien [CEA, LETI-Minatec, 17 Rue des Martyrs, 38054 Grenoble Cedex 9 (France); Appaix, Florence; De Waard, Michel, E-mail: fabien.sauter@cea.fr, E-mail: michel.dewaard@ujf-grenoble.fr [Inserm U836, Grenoble Institute of Neuroscience, Site Sante la Tronche, Batiment Edmond J Safra, Chemin Fortune Ferrini, BP170, 38042 Grenoble Cedex 09 (France)

    2011-05-13

    Carbon nanotube substrates are promising candidates for biological applications and devices. Interfacing of these carbon nanotubes with neurons can be controlled by chemical modifications. In this study, we investigated how chemical surface functionalization of multi-walled carbon nanotube arrays (MWNT-A) influences neuronal adhesion and network organization. Functionalization of MWNT-A dramatically modifies the length of neurite fascicles, cluster inter-connection success rate, and the percentage of neurites that escape from the clusters. We propose that chemical functionalization represents a method of choice for developing applications in which neuronal patterning on MWNT-A substrates is required.

  11. Simulated annealing (SA to vehicle routing problems with soft time windows

    Directory of Open Access Journals (Sweden)

    Suphan Sodsoon

    2014-12-01

    Full Text Available The researcher has applied and develops the meta-heuristics method to solve Vehicle Routing Problems with Soft Time Windows (VRPSTW. For this case there was only one depot, multi customers which each generally sparse either or demand was different though perceived number of demand and specific period of time to receive them. The Operation Research was representative combinatorial optimization problems and is known to be NP-hard. In this research algorithm, use Simulated Annealing (SA to determine the optimum solutions which rapidly time solving. After developed the algorithms, apply them to examine the factors and the optimum extended time windows and test these factors with vehicle problem routing under specific time windows by Solomon in OR-Library in case of maximum 25 customers. Meanwhile, 6 problems are including of C101, C102, R101, R102, RC101 and RC102 respectively. The result shows the optimum extended time windows at level of 50%. At last, after comparison these answers with the case of vehicle problem routing under specific time windows and flexible time windows, found that percentage errors on number of vehicles approximately by -28.57% and percentage errors on distances approximately by -28.57% which this algorithm spent average processing time on 45.5 sec/problems.

  12. Effects of gas composition on the growth of multi-walled carbon nanotube

    International Nuclear Information System (INIS)

    Fang, T.-H.; Chang, W.-J.; Lu, D.-M.; Lien, W.-C.

    2007-01-01

    This paper studies the effects of different gas compositions on the growth of multi-walled carbon nanotube (MWCNT) films by using an electron cyclotron resonance chemical vapor deposition (ECR-CVD) method. The Raman spectrum was employed to explore the composition of the MWCNT films grown under different mixtures of C 3 H 8 and H 2 . The results showed that the optimum relative intensity ratio of the D band to G band (i.e., I D /I G ) is 2 for the cases considered in this study. In addition, the morphology and microstructure of the MWCNTs were examined by field emission scanning electron microscopy (FE-SEM) and field emission gun transmission electron microscopy (FEG-TEM). Furthermore, atomic force microscopy (AFM) and scanning thermal microscopy (SThM) were used to study the surface topography and thermal properties of the MWCNTs

  13. Growth of small diameter multi-walled carbon nanotubes by arc discharge process

    International Nuclear Information System (INIS)

    Chaudhary, K. T.; Ali, J.; Yupapin, P. P.

    2014-01-01

    Multi-walled carbon nanotubes (MWCNTs) are grown by arc discharge method in a controlled methane environment. The arc discharge is produced between two graphite electrodes at the ambient pressures of 100 torr, 300 torr, and 500 torr. Arc plasma parameters such as temperature and density are estimated to investigate the influences of the ambient pressure and the contributions of the ambient pressure to the growth and the structure of the nanotubes. The plasma temperature and density are observed to increase with the increase in the methane ambient pressure. The samples of MWCNT synthesized at different ambient pressures are analyzed using transmission electron microscopy, scanning electron microscopy, Raman spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. An increase in the growth of MWCNT and a decrease in the inner tube diameter are observed with the increase in the methane ambient pressure

  14. Functionalization of multi-walled carbon nanotubes with iron phthalocyanine via a liquid chemical reaction for oxygen reduction in alkaline media

    Science.gov (United States)

    Yan, Xiaomei; Xu, Xiao; Liu, Qin; Guo, Jia; Kang, Longtian; Yao, Jiannian

    2018-06-01

    Iron single-atom catalyst in form of iron-nitrogen-carbon structure possesses the excellent catalytic activity in various chemical reactions. However, exploring a sustainable and stable single-atom metal catalyst still faces a great challenge due to low yield and complicated synthesis. Here, we report a functional multi-wall carbon nanotubes modified with iron phthalocyanine molecules via a liquid chemical reaction and realize the performance of similar single-atom catalysis for oxygen reduction reaction. A serial of characterizations strongly imply the structure change of iron phthalocyanine molecule and its close recombination with multi-wall carbon nanotubes, which are in favor of ORR catalysis. Compared to commercial platinum-carbon catalyst, composites exhibit superior activity for oxygen reduction reaction with higher half-wave potential (0.86 V), lower Tafel slope (38 mV dec-1), higher limiting current density and excellent electrochemical stability. The corresponding Zinc-air battery also presents higher maximum power density and discharge stability. Therefore, these findings provide a facile route to synthesize a highly efficient non-precious metal carbon-based catalyst.

  15. Synthesis of multi-walled carbon nanotubes/{beta}-FeOOH nanocomposites with high adsorption capacity

    Energy Technology Data Exchange (ETDEWEB)

    Song Haojie, E-mail: shj6922@163.com [School of Materials Science and Engineering, Jiangsu University (China); Liu Lei [Pharmaceutic College of Henan University (China); Jia Xiaohua; Min Chunying [School of Materials Science and Engineering, Jiangsu University (China)

    2012-12-15

    A hybrid nanostructure of multi-walled carbon nanotubes (CNTs) and {beta}-ferric oxyhydroxide ({beta}-FeOOH) nanoparticles is synthesized by ultrasonic-assisted in situ hydrolysis of the precursor ferric chloride and CNTs. Characterization by X-ray diffraction, scanning electron microscopy , and transmission electron microscopy establishes the nanohybrid structure of the synthesized sample. The results revealed that the surface of CNTs was uniformly assembled by numerous {beta}-FeOOH nanoparticles and had an average diameter of 3 nm. The formation route of anchoring {beta}-FeOOH nanoparticles onto CNTs was proposed as the intercalation and adsorption of iron ions onto the wall of CNTs, followed by the nucleation and growth of {beta}-FeOOH nanoparticles. The values of remanent magnetization (M{sub r}) and coercivity (H{sub c}) of the as-synthesized CNTs/{beta}-FeOOH nanocomposites were 0.1131 emu g, and 490.824 Oe, respectively. Furthermore, CNTs/{beta}-FeOOH nanocomposites showed a very high adsorption capacity of Congo red and thus these nanocomposites can be used as good adsorbents and can be used for the removal of the dye of Congo red from the waste water system.

  16. Multi-walled carbon nanotube-induced genotoxic, inflammatory and pro-fibrotic responses in mice: Investigating the mechanisms of pulmonary carcinogenesis

    DEFF Research Database (Denmark)

    Rahman, Luna; Jacobsen, Nicklas Raun; Aziz, Syed Abdul

    2017-01-01

    The International Agency for Research on Cancer has classified one type of multi-walled carbon nanotubes (MWCNTs) as possibly carcinogenic to humans. However, the underlying mechanisms of MWCNT- induced carcinogenicity are not known. In this study, the genotoxic, mutagenic, inflammatory, and fibr......The International Agency for Research on Cancer has classified one type of multi-walled carbon nanotubes (MWCNTs) as possibly carcinogenic to humans. However, the underlying mechanisms of MWCNT- induced carcinogenicity are not known. In this study, the genotoxic, mutagenic, inflammatory......, and fibrotic potential of MWCNTs were investigated. Muta™Mouse adult females were exposed to 36±6 or 109±18μg/mouse of Mitsui-7, or 26±2 or 78±5μg/mouse of NM-401, once a week for four consecutive weeks via intratracheal instillations, alongside vehicle-treated controls. Samples were collected 90days following...... extents. However, there was no evidence of DNA damage as measured by the comet assay following Mitsui-7 exposure, or increases in lacZ mutant frequency, for either MWCNTs. Increased p53 expression was observed in the fibrotic foci induced by both MWCNTs. Gene expression analysis revealed perturbations...

  17. Detection of Quinoline in G. boninense-Infected Plants Using Functionalized Multi-Walled Carbon Nanotubes: A Field Study.

    Science.gov (United States)

    Akanbi, Fowotade Sulayman; Yusof, Nor Azah; Abdullah, Jaafar; Sulaiman, Yusran; Hushiarian, Roozbeh

    2017-07-01

    Carbon nanotubes (CNTs) reinforced with gold nanoparticles (AuNPs) and chitosan nanoparticles (CTSNPs) were anchored on a screen-printed electrode to fabricate a multi-walled structure for the detection of quinoline. The surface morphology of the nanocomposites and the modified electrode was examined by an ultra-high resolution field emission scanning electron microscope (FESEM), and Fourier-transform infrared (FT-IR) spectroscopy was used to confirm the presence of specific functional groups on the multi-walled carbon nanotubes MWCNTs. Cyclic voltammetry (CV) and linear sweep voltammetry (LSV) were used to monitor the layer-by-layer assembly of ultra-thin films of nanocomposites on the surface of the electrode and other electrochemical characterizations. Under optimized conditions, the novel sensor displayed outstanding electrochemical reactivity towards the electro-oxidation of quinoline. The linear range was fixed between 0.0004 and 1.0 μM, with a limit of detection (LOD) of 3.75 nM. The fabricated electrode exhibited high stability with excellent sensitivity and selectivity, specifically attributable to the salient characteristics of AuNPs, CTSNPs, and MWCNTs and the synergistic inter-relationship between them. The newly developed electrode was tested in the field. The Ipa increased with an increase in the amount of quinoline solution added, and the peak potential deviated minimally, depicting the real capability of the newly fabricated electrode.

  18. Proficiency feasibility of multi-walled carbon nanotubes in the presence of polymeric surfactant on enhanced oil recovery

    Science.gov (United States)

    Nezhad, Javad Razavi; Jafari, Arezou; Abdollahi, Mahdi

    2018-01-01

    Enhanced heavy oil recovery methods are widely utilized to increase oil recovery. For this purpose, polymer and surfactant flooding have been used extensively. Recently, polymeric surfactant flooding has become an attractive alternative to sole polymer flooding due to their capability of providing an increase in solution viscosity and a decrease in interfacial tension, which are both beneficial for efficiency of the process. Applying nanoparticles as an additive to polymer solutions is a method to improve viscosity and alter rock wettability. Therefore, in this research, multi-walled carbon nanotube (MWCNT) was mixed with a polymeric surfactant of polyacrylamide-graft-lignin copolymer (PAM-g-L) synthesized via radical grafting reaction. Moreover, several solutions with different concentrations of nanoparticles with PAM-g-L were prepared. The solutions were injected into a micromodel to evaluate the PAM-g-L flooding efficiency in presence of the multi-walled carbon nanotubes. The results of micromodel flooding showed that increasing MWCNT concentration results in lower sweep efficiencies; and consequently, oil production will decrease. Therefore, MWCNT along with PAM-g-L has an unacceptable performance in enhanced heavy oil recovery. But data of wettability tests revealed that MWCNT can change the wettability from oil-wet to water-wet. In addition, the combination of the PAM-g-L and MWCNT in a solution will cause more water-wet condition.

  19. Detection of Quinoline in G. boninense-Infected Plants Using Functionalized Multi-Walled Carbon Nanotubes: A Field Study

    Directory of Open Access Journals (Sweden)

    Fowotade Sulayman Akanbi

    2017-07-01

    Full Text Available Carbon nanotubes (CNTs reinforced with gold nanoparticles (AuNPs and chitosan nanoparticles (CTSNPs were anchored on a screen-printed electrode to fabricate a multi-walled structure for the detection of quinoline. The surface morphology of the nanocomposites and the modified electrode was examined by an ultra-high resolution field emission scanning electron microscope (FESEM, and Fourier-transform infrared (FT-IR spectroscopy was used to confirm the presence of specific functional groups on the multi-walled carbon nanotubes MWCNTs. Cyclic voltammetry (CV and linear sweep voltammetry (LSV were used to monitor the layer-by-layer assembly of ultra-thin films of nanocomposites on the surface of the electrode and other electrochemical characterizations. Under optimized conditions, the novel sensor displayed outstanding electrochemical reactivity towards the electro-oxidation of quinoline. The linear range was fixed between 0.0004 and 1.0 μM, with a limit of detection (LOD of 3.75 nM. The fabricated electrode exhibited high stability with excellent sensitivity and selectivity, specifically attributable to the salient characteristics of AuNPs, CTSNPs, and MWCNTs and the synergistic inter-relationship between them. The newly developed electrode was tested in the field. The Ipa increased with an increase in the amount of quinoline solution added, and the peak potential deviated minimally, depicting the real capability of the newly fabricated electrode.

  20. Electromagnetic and thermal analysis of distributed cooled high power millimeter wave windows

    International Nuclear Information System (INIS)

    Nelson, S.D.; Reitter, T.; Caplan, M.; Moeller, C.

    1996-01-01

    The sectional high-frequency internally-cooled window, as proposed by General Atomics(1), has unique potential for allowing microwave sources to reach multi-megawatt CW levels with application to ECRH. Designs are being investigated using computational electromagnetic (EM), thermal, and mechanical codes at 110 GHz and 170 GHz to examine the design tradeoffs between RF performance and thermal mechanical safety margins. The EM analyses are for the window, under vacuum at one MW and includes variations in the shapes of the cooling fins, the surface treatment of the window elements themselves, the cooling fin tip treatment, the window pitch angle, and the waveguide effects. One advantage of the distributed cooled window is it close-quote s extensibility to higher power levels. Results in the modeling efforts are presented showing the EM field concentrations (which then will feed into the thermal analysis), the energy scattering/reflection, the transmitted launch angle variation as a function of physical geometry, and the spatial energy distribution and loss as a function of time and position. copyright 1996 American Institute of Physics

  1. 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: loboao@yahoo.com [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

    2012-05-01

    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.

  2. Dielectric properties of vertically aligned multi-walled carbon nanotubes in the terahertz and mid-infrared range

    Science.gov (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.

    2018-01-01

    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 \

  3. Synthesis and CO2 adsorption study of modified MOF-5 with multi-wall carbon nanotubes and expandable graphite

    International Nuclear Information System (INIS)

    Ullah, Sami; Bustam, M. A.; Shariff, A. M.; Elkhalifah, Ali E. I.; Murshid, G.; Riaz, Nadia

    2014-01-01

    MOF-5 was synthesized by solvothermal method and its reactivation under anhydrous conditions. This research is conducted to investigate the effect of MOF-5 and MOF-5 modified with multi-wall carbon nanotubes (MWCNTs) and expandable graphite (EG) on the performance of CO 2 adsorption. The synthesized MOFs were characterized using Field emission scanning electron microscopy (FESEM) for surface morphology, Thermogravimetric analysis (TGA) for thermal stability, X-ray diffraction (XRD) for crystals plane, Brunauer-Emmet-Teller (BET) for surface area and CO 2 adsorption. The result had showed that the modified MOF-5 enhanced the CO 2 adsorption compared to the pure MOF-5. The increment in the CO 2 uptake capacities of MOF materials was attributed to the decrease in the pore size and enhancement of micropore volume of MOF-5 by multi-walled carbon nanotube and EG incorporation. The BET surface area of the synthesized MOF-5@MWCNTs is more than MOF-5. The CO 2 sorption capacities of MOF-5 and MOF-5@MWCNTs were observed to increase from 0.00008 to 0.00048 mol g-1 at 298 K and 1 bar. The modified MOF-5@MWCNTs resulted in the highest CO 2 adsorption followed by the modified MOF-5@ EG and lastly, MOF-5

  4. Optimisation of the electromagnetic matching of manganese dioxide/multi-wall carbon nanotube composites as dielectric microwave-absorbing materials

    International Nuclear Information System (INIS)

    Ting, Tzu-Hao; Chiang, Chih-Chia; Lin, Po-Chuan; Lin, Chia-Huei

    2013-01-01

    An optimised composite sample was prepared using two dielectric materials manganese dioxide (MnO 2 ) and multi-wall carbon nanotubes (MWNTs) in an epoxy-resin matrix. Structural characterisations of both the synthesised manganese dioxide (MnO 2 ) and the multi-wall carbon nanotubes (MWNTs) were performed by using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The microwave absorption properties of dielectric composites with different weight fractions of MnO 2 were investigated by measuring the complex permittivity, the complex permeability and the reflection loss in the 2–18 and 18–40 GHz microwave frequency ranges using the free space method. The complex permittivity varied with the MnO 2 content, and the results show that a high concentration of fillers increased the dielectric constant. Therefore, the appropriate combination of components and experimental conditions can produce materials with specific characteristic for use as wide-band microwave absorbers. - Highlights: ► This paper analyses optimised microwave absorption for MnO 2 /MWNT composites. ► Structural characterisations were performed by using XRD and SEM. ► Increasing MnO 2 content enhances the complex permittivity in MnO 2 /MWNT matrix. ► The reflection loss varies with changes content of MnO 2 for required frequency bands

  5. Immobilization of ruthenium phthalocyanine on silica-coated multi-wall partially oriented carbon nanotubes: Electrochemical detection of fenitrothion pesticide

    Energy Technology Data Exchange (ETDEWEB)

    Canevari, Thiago C., E-mail: tccanevari@gmail.com [Engineering School, Mackenzie Presbyterian University, 01302-907 São Paulo, SP (Brazil); Prado, Thiago M.; Cincotto, Fernando H.; Machado, Sergio A.S. [Institute of Chemistry, State University of São Paulo, P.O. Box 780, 13560-970 São Carlos, SP (Brazil)

    2016-04-15

    Highlights: • Hybrid material, SiO{sub 2}/MWCNTs containing ruthenium phthalocyanine (RuPc) synthesized in situ. • Silica containing multi-walled carbon nanotube partially oriented. • Determination of pesticide fenitrothion in orange juice. - Abstract: This paper reports on the determination of the pesticide fenitrothion using a glassy carbon electrode modified with silica-coated, multi-walled, partially oriented carbon nanotubes, SiO{sub 2}/MWCNTs, containing ruthenium phthalocyanine (RuPc) synthesized in situ. The hybrid SiO{sub 2}/MWCNTs/RuPc material was characterized by UV–vis absorption spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM) and differential pulse voltammetry. The modified electrode showed well-defined peaks in the presence of fenitrothion in acetate buffer, pH 4.5, with a sensitivity of 0.0822 μA μM{sup −1} mm{sup −2} and a detection limit of 0.45 ppm. Notably, the modified SiO{sub 2}/MWCNTs/RuPc electrodes with did not suffer from significant influences in the presence of other organophosphorus pesticides during the determination of the fenitrothion pesticide. Moreover, this modified electrode showed excellent performance in the determination of fenitrothion in orange juice.

  6. Synthesis of highly dispersed Pd nanoparticles supported on multi-walled carbon nanotubes and their excellent catalytic performance for oxidation of benzyl alcohol

    NARCIS (Netherlands)

    Shinde, V.M.; Skupien, E.; Makkee, M.

    2015-01-01

    Narrow sized and highly homogeneous dispersed Pd nanoparticles have been synthesized on nitric acid-functionalized multi-walled carbon nanotubes (CNTs) without a capping agent. The TEM images show that the extremely small Pd nanoparticles with an average size of about 1.5 nm were homogeneously

  7. 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

    2010-09-01

    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...

  8. A Review of Double-Walled and Triple-Walled Carbon Nanotube Synthesis and Applications

    Directory of Open Access Journals (Sweden)

    Kazunori Fujisawa

    2016-04-01

    Full Text Available Double- and triple-walled carbon nanotubes (DWNTs and TWNTs consist of coaxially-nested two and three single-walled carbon nanotubes (SWNTs. They act as the geometrical bridge between SWNTs and multi-walled carbon nanotubes (MWNTs, providing an ideal model for studying the coupling interactions between different shells in MWNTs. Within this context, this article comprehensively reviews various synthetic routes of DWNTs’ and TWNTs’ production, such as arc discharge, catalytic chemical vapor deposition and thermal annealing of pea pods (i.e., SWNTs encapsulating fullerenes. Their structural features, as well as promising applications and future perspectives are also discussed.

  9. Set Up of an Automated Multi-Colour System for Interior Wall Painting

    Directory of Open Access Journals (Sweden)

    Berardo Naticchia

    2008-11-01

    Full Text Available It is shared that construction projects are getting bigger and more complex, hence also the productivity of the construction industry must be improved, while preserving its labour from hazardous job sites. Such requirements can be accomplished by the adoption of robotized products, which, however, need to be quickly developed and marketed. In this paper, first the issue of a new miniature laboratory for developing lightweight and well-coordinated robotized systems is pursued, then a novel robot device for high quality multi-colour interior wall painting carried by a robot arm is developed and successfully tested. Thanks to the new 1:6 scaled down laboratory and its six degree of freedom robot arm on an hexapod for horizontal moves, we tested the opportunity to introduce also in the building sector miniature robots that can change the ergonomics standardly adopted by construction workers. It is analyzed how and why switching from full size to miniature robots is convenient in construction. In addition, a new system adding further features to robotized painting has been conceived. Our new multi-colour spraying end-tool was developed and fixed on the robot arm, in order to be able to reproduce coloured artworks. Finally, a methodology to reproduce colours from digital format of artworks is presented, showing how accurate and efficient is this new robotized spraying device.

  10. Set up of an Automated Multi-Colour System for Interior Wall Painting

    Directory of Open Access Journals (Sweden)

    Berardo Naticchia

    2007-12-01

    Full Text Available It is shared that construction projects are getting bigger and more complex, hence also the productivity of the construction industry must be improved, while preserving its labour from hazardous job sites. Such requirements can be accomplished by the adoption of robotized products, which, however, need to be quickly developed and marketed. In this paper, first the issue of a new miniature laboratory for developing lightweight and well-coordinated robotized systems is pursued, then a novel robot device for high quality multi-colour interior wall painting carried by a robot arm is developed and successfully tested. Thanks to the new 1:6 scaled down laboratory and its six degree of freedom robot arm on an hexapod for horizontal moves, we tested the opportunity to introduce also in the building sector miniature robots that can change the ergonomics standardly adopted by construction workers. It is analyzed how and why switching from full size to miniature robots is convenient in construction. In addition, a new system adding further features to robotized painting has been conceived. Our new multi-colour spraying end-tool was developed and fixed on the robot arm, in order to be able to reproduce coloured artworks. Finally, a methodology to reproduce colours from digital format of artworks is presented, showing how accurate and efficient is this new robotized spraying device.

  11. Subcutaneous injection of water-soluble multi-walled carbon nanotubes in tumor-bearing mice boosts the host immune activity

    International Nuclear Information System (INIS)

    Meng Jie; Yang Man; Jia Fumin; Kong Hua; Zhang Weiqi; Xu Haiyan; Wang Chaoying; Xie Sishen; Xing Jianmin

    2010-01-01

    The immunological responses induced by oxidized water-soluble multi-walled carbon nanotubes on a hepatocarcinoma tumor-bearing mice model via a local administration of subcutaneous injection were investigated. Experimental results show that the subcutaneously injected carbon nanotubes induced significant activation of the complement system, promoted inflammatory cytokines' production and stimulated macrophages' phagocytosis and activation. All of these responses increased the general activity of the host immune system and inhibited the progression of tumor growth.

  12. Subcutaneous injection of water-soluble multi-walled carbon nanotubes in tumor-bearing mice boosts the host immune activity

    Science.gov (United States)

    Meng, Jie; Yang, Man; Jia, Fumin; Kong, Hua; Zhang, Weiqi; Wang, Chaoying; Xing, Jianmin; Xie, Sishen; Xu, Haiyan

    2010-04-01

    The immunological responses induced by oxidized water-soluble multi-walled carbon nanotubes on a hepatocarcinoma tumor-bearing mice model via a local administration of subcutaneous injection were investigated. Experimental results show that the subcutaneously injected carbon nanotubes induced significant activation of the complement system, promoted inflammatory cytokines' production and stimulated macrophages' phagocytosis and activation. All of these responses increased the general activity of the host immune system and inhibited the progression of tumor growth.

  13. Subcutaneous injection of water-soluble multi-walled carbon nanotubes in tumor-bearing mice boosts the host immune activity

    Energy Technology Data Exchange (ETDEWEB)

    Jie, Meng; Man, Yang; Fumin, Jia; Hua, Kong; Weiqi, Zhang; Haiyan, Xu [Department of Biomedical Engineering, Institute of Basic Medical Sciences and School of Basic Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, 5 Dong Dan San Tiao, Beijing 100005 (China); Chaoying, Wang; Sishen, Xie [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, 8 Nan San Jie, Zhongguancun, Beijing100080 (China); Xing Jianmin, E-mail: xuhy@pumc.edu.cn [Centre for Evidence-Based Chinese Medicine, Beijing University of Chinese Medicine, 11 Bei San Huan Dong Lu, Beijing 100029 (China)

    2010-04-09

    The immunological responses induced by oxidized water-soluble multi-walled carbon nanotubes on a hepatocarcinoma tumor-bearing mice model via a local administration of subcutaneous injection were investigated. Experimental results show that the subcutaneously injected carbon nanotubes induced significant activation of the complement system, promoted inflammatory cytokines' production and stimulated macrophages' phagocytosis and activation. All of these responses increased the general activity of the host immune system and inhibited the progression of tumor growth.

  14. A comparison of multi-view 3D reconstruction of a rock wall using several cameras and a laser scanner

    Science.gov (United States)

    Thoeni, K.; Giacomini, A.; Murtagh, R.; Kniest, E.

    2014-06-01

    This work presents a comparative study between multi-view 3D reconstruction using various digital cameras and a terrestrial laser scanner (TLS). Five different digital cameras were used in order to estimate the limits related to the camera type and to establish the minimum camera requirements to obtain comparable results to the ones of the TLS. The cameras used for this study range from commercial grade to professional grade and included a GoPro Hero 1080 (5 Mp), iPhone 4S (8 Mp), Panasonic Lumix LX5 (9.5 Mp), Panasonic Lumix ZS20 (14.1 Mp) and Canon EOS 7D (18 Mp). The TLS used for this work was a FARO Focus 3D laser scanner with a range accuracy of ±2 mm. The study area is a small rock wall of about 6 m height and 20 m length. The wall is partly smooth with some evident geological features, such as non-persistent joints and sharp edges. Eight control points were placed on the wall and their coordinates were measured by using a total station. These coordinates were then used to georeference all models. A similar number of images was acquired from a distance of between approximately 5 to 10 m, depending on field of view of each camera. The commercial software package PhotoScan was used to process the images, georeference and scale the models, and to generate the dense point clouds. Finally, the open-source package CloudCompare was used to assess the accuracy of the multi-view results. Each point cloud obtained from a specific camera was compared to the point cloud obtained with the TLS. The latter is taken as ground truth. The result is a coloured point cloud for each camera showing the deviation in relation to the TLS data. The main goal of this study is to quantify the quality of the multi-view 3D reconstruction results obtained with various cameras as objectively as possible and to evaluate its applicability to geotechnical problems.

  15. A comparison of multi-view 3D reconstruction of a rock wall using several cameras and a laser scanner

    Directory of Open Access Journals (Sweden)

    K. Thoeni

    2014-06-01

    Full Text Available This work presents a comparative study between multi-view 3D reconstruction using various digital cameras and a terrestrial laser scanner (TLS. Five different digital cameras were used in order to estimate the limits related to the camera type and to establish the minimum camera requirements to obtain comparable results to the ones of the TLS. The cameras used for this study range from commercial grade to professional grade and included a GoPro Hero 1080 (5 Mp, iPhone 4S (8 Mp, Panasonic Lumix LX5 (9.5 Mp, Panasonic Lumix ZS20 (14.1 Mp and Canon EOS 7D (18 Mp. The TLS used for this work was a FARO Focus 3D laser scanner with a range accuracy of ±2 mm. The study area is a small rock wall of about 6 m height and 20 m length. The wall is partly smooth with some evident geological features, such as non-persistent joints and sharp edges. Eight control points were placed on the wall and their coordinates were measured by using a total station. These coordinates were then used to georeference all models. A similar number of images was acquired from a distance of between approximately 5 to 10 m, depending on field of view of each camera. The commercial software package PhotoScan was used to process the images, georeference and scale the models, and to generate the dense point clouds. Finally, the open-source package CloudCompare was used to assess the accuracy of the multi-view results. Each point cloud obtained from a specific camera was compared to the point cloud obtained with the TLS. The latter is taken as ground truth. The result is a coloured point cloud for each camera showing the deviation in relation to the TLS data. The main goal of this study is to quantify the quality of the multi-view 3D reconstruction results obtained with various cameras as objectively as possible and to evaluate its applicability to geotechnical problems.

  16. Window Stories

    DEFF Research Database (Denmark)

    Hauge, Bettina

    This research project has investigated 17 households in Germany (cities and rural areas). The main aim was to learn about the significance of the window to these people: What they think of their windows, how, when and why they use them in their everyday life, if they have a favorite window and wh...

  17. Windows 10 simplified

    CERN Document Server

    McFedries, Paul

    2015-01-01

    Learn Windows 10 quickly and painlessly with this beginner's guide Windows 10 Simplified is your absolute beginner's guide to the ins and outs of Windows. Fully updated to cover Windows 10, this highly visual guide covers all the new features in addition to the basics, giving you a one-stop resource for complete Windows 10 mastery. Every page features step-by-step screen shots and plain-English instructions that walk you through everything you need to know, no matter how new you are to Windows. You'll master the basics as you learn how to navigate the user interface, work with files, create

  18. Windows and doors

    Energy Technology Data Exchange (ETDEWEB)

    1988-01-01

    A complete manual is presented on windows and doors for the housing contractor. In order to understand the role of windows and doors in a house's energy performance, an introduction explains the house as a system of components that can have effects on each other. Further chapters explain in detail the parts of a window, window types and RSI values; window servicing and repair; window replacement; parts of a door, door types and RSI values; door service and repair, including weatherstripping; door replacement; and how to ensure quality, service, and customer satisfaction. A glossary of terms is included. 61 figs., 3 tabs.

  19. Design of a test-bench to validate a model of a thermal window design; Diseno de un banco de ensayos para la validacion de un modelo de diseno termico de ventanas

    Energy Technology Data Exchange (ETDEWEB)

    Saavedra O, Claudio; Fissore Sch, Adelqui; Mottard, Jean-Michel [Universidad de Concepcion (Chile). Facultad de Ingenieria. Dept. de Ingenieria Mecanica]. E-mail: clsaaved @udec.cl; afissore@udec.cl

    2000-07-01

    Paper presents the design of a test-bench and instrumentation to validate a window thermal mathematical model. The test-bench simulate the thermal performance of a office with a only one wall in directly contact with outdoors, where a single glass window is mounted. To obtain a similar heat transfer relation as the real building, the chamber has been designed and manufactured with an inner and an outer envelope, and with an air spacing maintaining at the same temperature that the test chamber. To change the window size, the test-bench is equipped with a single modifiable outer wall. Instrumentation and methods of measurement for solar radiation, infra red outdoor radiation, indoor and outdoor air temperatures, wind velocity, heat transfer, air ventilating flow and temperature, wall temperatures, etc. are specified. (author)

  20. Imaging of left ventricular wall motion via venous DSA

    International Nuclear Information System (INIS)

    Witte, G.; Roediger, W.; Buecheler, E.; Hamburg Univ.

    1986-01-01

    Until now, angiographical and nuclear medicine examination techniques for imaging left ventricular wall motion have been presenting with difficulties endemic to the methods themselves. For the first time in cardiological diagnostics, digital subtraction angiography (DSA) makes it possible to perform a fairly non-invasive examination with good spatial and temporal resolution. Functional analytic evaluation, however, still demands time-consuming, complicated post-processing. In this article we introduce a method that uses an additive window technique for the immediate generation of wall motion images. (orig.) [de

  1. The Role of Multi-wall Carbon Nanotubes on Fracture Mechanism of Epoxy Nanocomposite

    Directory of Open Access Journals (Sweden)

    M. Hooshiar Sadegian

    2008-12-01

    Full Text Available In order to investigate the role of multi-wall carbon nanotubes (MWCNTs on fracture mechanism of epoxy nanocomposites, a series of tensile standard specimens reinforced with different carbon nanotube contents (0, 0.3, 0.6 and 1 wt% were produced. The fracture surfaces of the produced nanocomposites were evaluated using scanning electron microscope (SEM. The results show that the surface fracture of epoxy nanocomposites comprised of three regions, i.e. mirror, transition and final propagation zones. The extension of all zones depends strongly on curing agent as well asMWCNTs content. The mirror zone is disappeared as curing agent and MWCNTs content increases, while the transition zone depends on the nucleation rate of secondary microcrack. The pattern of final propagation zone becomes coarser as MWCNTs are added to epoxy system.

  2. Peripheral pulmonary arteries: identification at multi-slice spiral CT with 3D reconstruction

    International Nuclear Information System (INIS)

    Coche, Emmanuel; Pawlak, Sebastien; Dechambre, Stephane; Maldague, Baudouin

    2003-01-01

    Our objective was to analyze the peripheral pulmonary arteries using thin-collimation multi-slice spiral CT. Twenty consecutive patients underwent enhanced-spiral multi-slice CT using 1-mm collimation. Two observers analyzed the pulmonary arteries by consensus on a workstation. Each artery was identified on axial and 3D shaded-surface display reconstruction images. Each subsegmental artery was measured at a mediastinal window setting and compared with anatomical classifications. The location and branching of every subsegmental artery was recorded. The number of well-visualized sub-subsegmental arteries at a mediastinal window setting was compared with those visualized at a lung window setting. Of 800 subsegmental arteries, 769 (96%) were correctly visualized and 123 accessory subsegmental arteries were identified using the mediastinal window setting. One thousand ninety-two of 2019 sub-subsegmental arteries (54%) identified using the lung window setting were correctly visualized using the mediastinal window setting. Enhanced multi-slice spiral CT with thin collimation can be used to analyze precisely the subsegmental pulmonary arteries and may identify even more distal pulmonary arteries. (orig.)

  3. Ultraviolet pulsed laser irradiation of multi-walled carbon nanotubes in nitrogen atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Pérez del Pino, Ángel, E-mail: aperez@icmab.es; Cabana, Laura; Tobias, Gerard [Instituto de Ciencia de Materiales de Barcelona, Consejo Superior de Investigaciones Científicas (ICMAB-CSIC), Campus UAB, 08193 Bellaterra (Spain); György, Enikö [Instituto de Ciencia de Materiales de Barcelona, Consejo Superior de Investigaciones Científicas (ICMAB-CSIC), Campus UAB, 08193 Bellaterra (Spain); National Institute for Lasers, Plasma and Radiation Physics, P. O. Box MG 36, 76900 Bucharest V (Romania); Ballesteros, Belén [ICN2—Institut Catala de Nanociencia i Nanotecnologia, Campus UAB, 08193 Bellaterra, Barcelona (Spain)

    2014-03-07

    Laser irradiation of randomly oriented multi-walled carbon nanotube (MWCNT) networks has been carried out using a pulsed Nd:YAG UV laser in nitrogen gas environment. The evolution of the MWCNT morphology and structure as a function of laser fluence and number of accumulated laser pulses has been studied using electron microscopies and Raman spectroscopy. The observed changes are discussed and correlated with thermal simulations. The obtained results indicate that laser irradiation induces very fast, high temperature thermal cycles in MWCNTs which produce the formation of different nanocarbon forms, such as nanodiamonds. Premelting processes have been observed in localized sites by irradiation at low number of laser pulses and low fluence values. The accumulation of laser pulses and the increase in the fluence cause the full melting and amorphization of MWCNTs. The observed structural changes differ from that of conventional high temperature annealing treatments of MWCNTs.

  4. Superior Performance Nanocomposites from Uniformly Dispersed Octadecylamine Functionalized Multi-Walled Carbon Nanotubes

    KAUST Repository

    Chen, Ye

    2015-12-08

    Polyetherimide (PEI) is a widely applied as engineering plastic in the electronics, aerospace, and automotive industries but the disadvantages of extremely low conductivity, atmospheric moisture absorption, and poor fluidity at high temperature limits its application. Herein, commercial multi-walled carbon nanotubes (MWCNTs) were modified with a long alkyl chain molecule, octadecylamine (ODA), to produce a uniform dispersion in commercial PEI matrices. Both covalent and noncovalent modification of MWCNTs with ODA, were prepared and compared. Modified MWCNTs were incorporated in PEI matrices to fabricate nanocomposite membranes by a simple casting method. Investigating mechanical properties, thermal stability, and conductivity of the polyetherimide (PEI)/MWCNT composites showed a unique combination of properties, such as high electrical conductivity, high mechanical properties, and high thermal stability at a low content of 1.0 wt % loading of ODA modified MWCNTs. Moreover, electrical resistivity decreased around 10 orders of magnitude with only 0.5 wt % of modified MWCNTs.

  5. Superior Performance Nanocomposites from Uniformly Dispersed Octadecylamine Functionalized Multi-Walled Carbon Nanotubes

    KAUST Repository

    Chen, Ye; Tao, Jing; Ezzeddine, Alaa; Mahfouz, Remi; Al-Shahrani, Abdullah; Alabedi, Gasan; Khashab, Niveen M.

    2015-01-01

    Polyetherimide (PEI) is a widely applied as engineering plastic in the electronics, aerospace, and automotive industries but the disadvantages of extremely low conductivity, atmospheric moisture absorption, and poor fluidity at high temperature limits its application. Herein, commercial multi-walled carbon nanotubes (MWCNTs) were modified with a long alkyl chain molecule, octadecylamine (ODA), to produce a uniform dispersion in commercial PEI matrices. Both covalent and noncovalent modification of MWCNTs with ODA, were prepared and compared. Modified MWCNTs were incorporated in PEI matrices to fabricate nanocomposite membranes by a simple casting method. Investigating mechanical properties, thermal stability, and conductivity of the polyetherimide (PEI)/MWCNT composites showed a unique combination of properties, such as high electrical conductivity, high mechanical properties, and high thermal stability at a low content of 1.0 wt % loading of ODA modified MWCNTs. Moreover, electrical resistivity decreased around 10 orders of magnitude with only 0.5 wt % of modified MWCNTs.

  6. MS Windows domēna darbstacijas migrācijas iespējas no MS Windows XP uz MS Windows 7.

    OpenAIRE

    Zariņš, Valdis

    2009-01-01

    Kvalifikācijas darbā tiek aprakstītas MS Windows domēna darbstacijas migrācijas iespējas no MS Windows XP uz MS Windows 7, kā servera operētājsistēmas izmantojot tādus Microsoft produktus, kā Microsoft Windows Server 2003 un Microsoft Windows Server 2008. Kvalifikācijas darba teorētiskaja daļā tiek apskatīti Microsoft Windows 7 priekšrocības un uzlabojumus gan no darbstacijas lietotāja , gan no darbstacijas administratora puses. Ir aprakstītas Microsoft Windows Server 2008 jauninājumu ie...

  7. Optimized network of multi-walled carbon nanotubes for chemical sensing

    International Nuclear Information System (INIS)

    Gohier, A; Chancolon, J; Porterat, D; Mayne-L'Hermite, M; Reynaud, C; Chenevier, P

    2011-01-01

    This work reports the design of a resistive gas sensor based on 2D mats of multi-walled carbon nanotubes (MWCNTs) grown by aerosol-assisted chemical vapour deposition. The sensor sensitivity was optimized using chlorine as analyte by tuning both CNT network morphology and CNT electronic properties. Optimized devices, operating at room temperature, have been calibrated over a large range of concentration and are shown to be sensitive down to 27 ppb of chlorine. The as-grown MWCNT response is compared with responses of 2000 deg. C annealed CNTs, as well as of nitrogen-doped CNTs and CNTs functionalized with polyethyleneimine (PEI). Under chlorine exposure, the resistance decrease of as-grown and annealed CNTs is attributed to charge transfer from chlorine to CNTs and demonstrates their p-type semiconductor behaviour. XPS analysis of CNTs exposed to chlorine shows the presence of chloride species that confirms electron charge transfer from chlorine to CNTs. By contrast, the resistance of nitrogen-doped and PEI functionalized CNTs exposed to chlorine increases, in agreement with their n-type semiconductor nature. The best response is obtained using annealed CNTs and is attributed to their higher degree of crystallinity.

  8. Using Photosensitive Dye To Improve Multi Walled Carbon Nanotubes Dispersion

    Energy Technology Data Exchange (ETDEWEB)

    Diaz Costanzo, Guadalupe; Goyanes, Silvia [Laboratorio de PolImeros y Materiales Compuestos, Dpto. de Fisica, FCEyN, Universidad de Buenos Aires (Argentina) (Argentina); Ledesma, Silvia, E-mail: ledesma@df.uba.ar [Laboratorio de Procesado de Imagenes, Dpto. de Fisica, FCEyN, Universidad de Buenos Aires (Argentina) (Argentina)

    2011-01-01

    As already well-known, the outstanding mechanical and electrical properties of carbon nanotubes (CNT) are partially lost when CNT aggregate. The fact that CNT tend to aggregate makes difficult to put them into a host matrix, for example. Until now, achieving stable dispersions of CNT is still a challenge. In the present work, we show that the addition of an azobenzene derivative, Disperse Orange 3 (DO3) to dispersions of multi walled carbon nanotubes (MWCNT) in the organic solvent tetrahydrofuran (THF) efficiently helps debundling MWCNT and makes dispersions stable for days. We report UV-Vis optical absorption experiments that suggest an interaction between MWCNT and DO3 molecules following the behavior qualitatively observed. Dispersions with MWCNT and DO3 in THF were observed qualitatively over time. Successful suspensions (for the higher DO3 concentrations studied) were stable for several days. Also, we prepared polymeric films doped with MWCNT non-covalent functionalized with DO3 in one of the proper DO3/MWCNT weight relation where stable supensions were obtained. In this study we show preliminary results where the optical response of these samples was also measured.

  9. Multi-walled carbon nanotubes (MWCNTs) functionalized with amino groups by reacting with supercritical ammonia fluids

    International Nuclear Information System (INIS)

    Shao Lu; Bai Yongping; Huang Xu; Gao Zhangfei; Meng Linghui; Huang Yudong; Ma Jun

    2009-01-01

    For the first time, supercritical ammonia fluid was utilized to simply functionalize multi-walled carbon nanotube (MWCNT) with amino groups. The successful amino functionalization of MWCNTs was proven and the physicochemical properties of MWCNTs before and after supercritical ammonia fluids modifications were characterized using X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), atomic force microscope (AFM) and Raman spectroscopy. The results also indicated that the supercritical ammonia fluids had the visible effects on the nanostructure of carbon nanotubes. Our novel modification approach provides an easy way to modify MWCNTs with amino groups, which is very useful for realizing 'carbon nanotube economy' in the near future.

  10. Car glass microphones using piezoelectric transducers for external alarm detection and localization

    Science.gov (United States)

    Bolzmacher, Christian; Le Guelvouit, Valentin

    2015-05-01

    This work describes the potential use of car windows as a long range acoustic sensing device for external alarm signals. The goal is to detect and localize siren signals (e.g. ambulances and police cars) and to alert presbycusic drivers of its presence by visual and acoustic feedback in order to improve individual mobility and increase the sense of security. The glass panes of a Renault Zoé operating as an acoustic antenna have been equipped with large 50 mm outer diameter piezoceramic rings, hidden in the lower part of the door structure and the lower part of the windshield and the rear window. The response of the glass to quasi-static signals and sweep excitation has been recorded. In general, the glass pane is acting as a high pass filter due to its inherent stiffness and provides only little damping. This effect is compensated by using a charge amplifier electronic circuit. The detection capability up to 120 m as well as a dynamic test where the car is moving towards the sound source is reported.

  11. Radon daughter concentrations in and around dwellings in the northern part of the Netherlands

    International Nuclear Information System (INIS)

    Wolfs, F.; Hofstede, H.; Meijer, R.J. de; Put, L.W.

    1984-01-01

    The concentration of radon daughters in and around 80 dwellings located in the northern part of the Netherlands has been determined using a one-filter method. Median values of 2.0 and 0.4 mWL were measured for the indoor and outdoor concentrations, respectively. The average outdoor concentration was about an order of magnitude higher for wind directions between SE-SW than for SW-NW. On average, dwellings with double pane windows and/or concrete floors were found to have significantly higher radon concentrations than those with single pane windows and/or wooden floors. For the living room of a particular dwelling, 18 measurements were carried out. The data for this dwelling indicate a linear relation between the concentration indoors and outdoors with a slope of 3.8 +- 2.0. This unexpected behaviour is thought to be related to ventilation via the crawl space. Measurements of ventilation patterns and measurements of radon concentrations in the living room and the crawl space are consistent with this picture. (author)

  12. Resources | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  13. Links | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  14. Efficient Windows Collaborative | Home

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  15. FAQ | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  16. Glossary | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  17. Multi-walled carbon nanotubes can enhance root elongation of wheat (Triticum aestivum) plants

    International Nuclear Information System (INIS)

    Wang Xiuping; Han Heyou; Liu Xueqin; Gu Xiaoxu; Chen Kun; Lu Donglian

    2012-01-01

    The potential effects of oxidized multi-walled carbon nanotubes (o-MWCNTs) with a length ranging from 50 to 630 nm on the development and physiology of wheat plants were evaluated by examining their effects on seed germination, root elongation, stem length, and vegetative biomass at a concentration ranging from 10 to 160 μg/mL in the plant. Results indicated that after 7 days of exposure to the o-MWCNTs medium, faster root growth and higher vegetative biomass were observed, but seed germination and stem length did not show any difference as compared with controls. Moreover, a physiological study was conducted at cellular level using a traditional physiological approach to evidence the possible alterations in morphology, the cell length of root zone, and the dehydrogenase activity of seedlings. Transmission electron microscopy images revealed that o-MWCNTs could penetrate the cell wall and enter the cytoplasm after being taken up by roots. The cell length of root zone for the seedlings germinated and grown in the o-MWCNTs (80 μg/mL) medium increased by 1.4-fold and a significant concentration-dependent increase in the dehydrogenase activity for the o-MWCNT-treated wheat seedlings was detected. These findings suggest that o-MWCNTs can significantly promote cell elongation in the root system and increase the dehydrogenase activity, resulting in faster root growth and higher biomass production.

  18. Multi-walled carbon nanotubes can enhance root elongation of wheat (Triticum aestivum) plants

    Energy Technology Data Exchange (ETDEWEB)

    Wang Xiuping; Han Heyou, E-mail: hyhan@mail.hzau.edu.cn; Liu Xueqin; Gu Xiaoxu; Chen Kun; Lu Donglian [Huazhong Agricultural University, College of Science, State Key Laboratory of Agricultural Microbiology, Institute of Chemical Biology (China)

    2012-06-15

    The potential effects of oxidized multi-walled carbon nanotubes (o-MWCNTs) with a length ranging from 50 to 630 nm on the development and physiology of wheat plants were evaluated by examining their effects on seed germination, root elongation, stem length, and vegetative biomass at a concentration ranging from 10 to 160 {mu}g/mL in the plant. Results indicated that after 7 days of exposure to the o-MWCNTs medium, faster root growth and higher vegetative biomass were observed, but seed germination and stem length did not show any difference as compared with controls. Moreover, a physiological study was conducted at cellular level using a traditional physiological approach to evidence the possible alterations in morphology, the cell length of root zone, and the dehydrogenase activity of seedlings. Transmission electron microscopy images revealed that o-MWCNTs could penetrate the cell wall and enter the cytoplasm after being taken up by roots. The cell length of root zone for the seedlings germinated and grown in the o-MWCNTs (80 {mu}g/mL) medium increased by 1.4-fold and a significant concentration-dependent increase in the dehydrogenase activity for the o-MWCNT-treated wheat seedlings was detected. These findings suggest that o-MWCNTs can significantly promote cell elongation in the root system and increase the dehydrogenase activity, resulting in faster root growth and higher biomass production.

  19. Windows® Internals

    CERN Document Server

    Russinovich, Mark E; Ionescu, Alex

    2009-01-01

    See how the core components of the Windows operating system work behind the scenes-guided by a team of internationally renowned internals experts. Fully updated for Windows Server 2008 and Windows Vista, this classic guide delivers key architectural insights on system design, debugging, performance, and support-along with hands-on experiments to experience Windows internal behavior firsthand.Delve inside Windows architecture and internals:Understand how the core system and management mechanisms work-from the object manager to services to the registryExplore internal system data structures usin

  20. Structural design study of a proton beam window for a 1-MW spallation neutron source

    Energy Technology Data Exchange (ETDEWEB)

    Teraoku, Takuji; Terada, Atsuhiko; Maekawa, Fujio; Meigo, Shin-ichiro; Kaminaga, Masanori; Ishikura, Syuichi; Hino, Ryutaro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2003-03-01

    A 1-MW spallation neutron source aiming at materials and life science researches will be constructed under the JAERI-KEK High-intensity Proton Accelerator Project (J-PARC). A proton beam passes through a proton beam window, and be injected into a target of the neutron source. The proton beam window functions as a boundary wall between a high vacuum area in the proton beam line and a helium atmosphere at about atmospheric pressure in a helium vessel which contains the target and moderators. The proton beam window is cooled by light water because high heat-density is generated in the window material by interactions with the proton beam. Then, uniformity of the water flow is requested at the window to suppress a hot-spot that causes excessive thermal stress and cooling water boiling. Also, the window has to be strong enough in its structure for inner stress due to water pressure and thermal stress due to heat generation. In this report, we propose two types of proton beam windows; one flat-type that is easy to manufacture, and the other, curved-type that has high stress resistivity. As a part of design study for the windows, evaluation of strength of structure and thermal hydraulic analysis were conducted. As a result, it was found that sufficient heat removal was assured with uniform water flow at the window, and stress caused by internal water pressure and thermal stress could be maintained below allowable stress values. Accordingly, it was confirmed that the proton beam window designs were feasible. (author)

  1. Improved field emission properties of thiolated multi-wall carbon nanotubes on a flexible carbon cloth substrate

    International Nuclear Information System (INIS)

    Chuang, F T; Chen, P Y; Cheng, T C; Chien, C H; Li, B J

    2007-01-01

    In this paper we report the observation of enhanced field emission properties from thiolated multi-wall carbon nanotubes (MWCNTs) produced by a simple and effective two-step chemical surface modification technique. This technique implements carboxylation and thiolation on the MWCNTs synthesized by microwave plasma chemical vapor deposition (MPCVD) on the flexible carbon cloth substrate. The resulting thiolated MWCNTs were found to have a very low threshold field value of 1.25 V μm -1 and a rather high field enhancement factor of 1.93 x 10 4 , which are crucial for applications in versatile vacuum microelectronics

  2. Modification of polydopamine-coated Fe3O4 nanoparticles with multi-walled carbon nanotubes for magnetic-μ-dispersive solid-phase extraction of antiepileptic drugs in biological matrices.

    Science.gov (United States)

    Zhang, Ruiqi; Wang, Siming; Yang, Ye; Deng, Yulan; Li, Di; Su, Ping; Yang, Yi

    2018-06-01

    In this study, multi-walled carbon nanotubes were coated on the surface of magnetic nanoparticles modified by polydopamine. The synthesized composite was characterized and applied to magnetic-μ-dispersive solid-phase extraction of oxcarbazepine (OXC), phenytoin (PHT), and carbamazepine (CBZ) from human plasma, urine, and cerebrospinal fluid samples prior to analysis by a high-performance liquid chromatography-photodiode array detector. The extraction parameters were investigated and the optimum condition was obtained when the variables were set to the following: sorbent type, Fe 3 O 4 @polyDA-MWCNTs (length Graphical abstract Magnetic multi-walled carbon nanotube core-shell composites were applied as magnetic-μ-dispersive solid-phase extraction adsorbents for determination of antiepileptic drugs in biological matrices.

  3. Dye-sensitized solar cells based on anatase TiO2/multi-walled carbon nanotubes composite nanofibers photoanode

    International Nuclear Information System (INIS)

    Du, Pingfan; Song, Lixin; Xiong, Jie; Li, Ni; Wang, Lijun; Xi, Zhenqiang; Wang, Naiyan; Gao, Linhui; Zhu, Hongliang

    2013-01-01

    Highlights: ► TiO 2 /multi-walled carbon nanotubes (MWCNTs) hybrid nanofibers are prepared via electrospinning. ► Dye-sensitized solar cells (DSSCs) are assembled using TiO 2 /MWCNTs nanofibers film as photoanode. ► Energy conversion efficiency of DSSCs is greatly dependent on the content of MWCNTs. ► Moderate MWCNTs incorporation can substantially enhance the performance of DSSCs. - Abstract: Anatase TiO 2 /multi-walled carbon nanotubes (TiO 2 /MWCNTs) hybrid nanofibers (NFs) film was prepared via a facile electrospinning method. Dye-sensitized solar cells (DSSCs) based on TiO 2 /MWCNTs composite NFs photoanodes with different contents of MWCNTs (0, 0.1, 0.3, 0.5, 1 wt.%) were assembled using N719 dye as sensitizer. Field emission scanning electron microscope (FESEM), transmission electron microscope (TEM), X-ray diffractometer (XRD), and Raman spectrometer were used to characterize the TiO 2 /MWCNTs electrode films. The photocurrent–voltage (I–V) characteristic, incident photo-to-current conversion efficiency (IPCE) spectrum, and electrochemical impedance spectroscopy (EIS) measurements were carried out to evaluate the photoelectric properties of the DSSCs. The results reveal that the energy conversion efficiency is greatly dependent on the content of MWCNTs in the composite NFs film, and a moderate incorporation of MWCNTs can substantially enhance the performance of DSSCs. When the electrode contains 0.3 wt.% MWCNTs, the corresponding solar cell yield the highest efficiency of 5.63%. This efficiency value is approximately 26% larger than that of the unmodified counterpart.

  4. Constricted nanowire with stabilized magnetic domain wall

    International Nuclear Information System (INIS)

    Sbiaa, R.; Al Bahri, M.

    2016-01-01

    Domain wall (DW)-based magnetic memory offers the possibility for increasing the storage capacity. However, stability of DW remains the major drawback of this scheme. In this letter, we propose a stepped nanowire for pinning DW in a desirable position. From micromagnetic simulation, the proposed design applied to in-plane magnetic anisotropy materials shows that by adjusting the nanowire step size and its width it is possible to stabilize DW for a desirable current density range. In contrast, only a movement of DW could be seen for conventional nanowire. An extension to a multi-stepped nanowire could be used for multi-bit per cell magnetic memory. - Highlights: • A stepped nanowire is proposed to pin domain wall in desired position. • The new structure can be made by a simple off set of two single nanowires. • The critical current for moving domain wall from one state to the other could be tuned by adjusting the geometry of the device. • The device could be used for multi-bit per cell memory by extending the steps in the device.

  5. Synthesis and CO{sub 2} adsorption study of modified MOF-5 with multi-wall carbon nanotubes and expandable graphite

    Energy Technology Data Exchange (ETDEWEB)

    Ullah, Sami, E-mail: samichemist1@gmail.com, E-mail: azmibustam@petronas.com.my, E-mail: azmish@petronas.com.my, E-mail: lkhlfh@gmail.com, E-mail: hmurshid@gmail.com, E-mail: nadiariazz@gmail.com; Bustam, M. A., E-mail: samichemist1@gmail.com, E-mail: azmibustam@petronas.com.my, E-mail: azmish@petronas.com.my, E-mail: lkhlfh@gmail.com, E-mail: hmurshid@gmail.com, E-mail: nadiariazz@gmail.com; Shariff, A. M., E-mail: samichemist1@gmail.com, E-mail: azmibustam@petronas.com.my, E-mail: azmish@petronas.com.my, E-mail: lkhlfh@gmail.com, E-mail: hmurshid@gmail.com, E-mail: nadiariazz@gmail.com; Elkhalifah, Ali E. I., E-mail: samichemist1@gmail.com, E-mail: azmibustam@petronas.com.my, E-mail: azmish@petronas.com.my, E-mail: lkhlfh@gmail.com, E-mail: hmurshid@gmail.com, E-mail: nadiariazz@gmail.com; Murshid, G., E-mail: samichemist1@gmail.com, E-mail: azmibustam@petronas.com.my, E-mail: azmish@petronas.com.my, E-mail: lkhlfh@gmail.com, E-mail: hmurshid@gmail.com, E-mail: nadiariazz@gmail.com; Riaz, Nadia, E-mail: samichemist1@gmail.com, E-mail: azmibustam@petronas.com.my, E-mail: azmish@petronas.com.my, E-mail: lkhlfh@gmail.com, E-mail: hmurshid@gmail.com, E-mail: nadiariazz@gmail.com [Research Center for Carbon Dioxide Capture, Dept. of Chemical Engineering, Universiti Teknologi PETRONAS, Bandar Sri Iskandar, Tronoh 31750 Perak (Malaysia)

    2014-10-24

    MOF-5 was synthesized by solvothermal method and its reactivation under anhydrous conditions. This research is conducted to investigate the effect of MOF-5 and MOF-5 modified with multi-wall carbon nanotubes (MWCNTs) and expandable graphite (EG) on the performance of CO{sub 2} adsorption. The synthesized MOFs were characterized using Field emission scanning electron microscopy (FESEM) for surface morphology, Thermogravimetric analysis (TGA) for thermal stability, X-ray diffraction (XRD) for crystals plane, Brunauer-Emmet-Teller (BET) for surface area and CO{sub 2} adsorption. The result had showed that the modified MOF-5 enhanced the CO{sub 2} adsorption compared to the pure MOF-5. The increment in the CO{sub 2} uptake capacities of MOF materials was attributed to the decrease in the pore size and enhancement of micropore volume of MOF-5 by multi-walled carbon nanotube and EG incorporation. The BET surface area of the synthesized MOF-5@MWCNTs is more than MOF-5. The CO{sub 2} sorption capacities of MOF-5 and MOF-5@MWCNTs were observed to increase from 0.00008 to 0.00048 mol g-1 at 298 K and 1 bar. The modified MOF-5@MWCNTs resulted in the highest CO{sub 2} adsorption followed by the modified MOF-5@ EG and lastly, MOF-5.

  6. Lagged kernel machine regression for identifying time windows of susceptibility to exposures of complex mixtures.

    Science.gov (United States)

    Liu, Shelley H; Bobb, Jennifer F; Lee, Kyu Ha; Gennings, Chris; Claus Henn, Birgit; Bellinger, David; Austin, Christine; Schnaas, Lourdes; Tellez-Rojo, Martha M; Hu, Howard; Wright, Robert O; Arora, Manish; Coull, Brent A

    2018-07-01

    The impact of neurotoxic chemical mixtures on children's health is a critical public health concern. It is well known that during early life, toxic exposures may impact cognitive function during critical time intervals of increased vulnerability, known as windows of susceptibility. Knowledge on time windows of susceptibility can help inform treatment and prevention strategies, as chemical mixtures may affect a developmental process that is operating at a specific life phase. There are several statistical challenges in estimating the health effects of time-varying exposures to multi-pollutant mixtures, such as: multi-collinearity among the exposures both within time points and across time points, and complex exposure-response relationships. To address these concerns, we develop a flexible statistical method, called lagged kernel machine regression (LKMR). LKMR identifies critical exposure windows of chemical mixtures, and accounts for complex non-linear and non-additive effects of the mixture at any given exposure window. Specifically, LKMR estimates how the effects of a mixture of exposures change with the exposure time window using a Bayesian formulation of a grouped, fused lasso penalty within a kernel machine regression (KMR) framework. A simulation study demonstrates the performance of LKMR under realistic exposure-response scenarios, and demonstrates large gains over approaches that consider each time window separately, particularly when serial correlation among the time-varying exposures is high. Furthermore, LKMR demonstrates gains over another approach that inputs all time-specific chemical concentrations together into a single KMR. We apply LKMR to estimate associations between neurodevelopment and metal mixtures in Early Life Exposures in Mexico and Neurotoxicology, a prospective cohort study of child health in Mexico City.

  7. Removal of copper ions from water using chemical modified multi-walled carbon nanotubes

    International Nuclear Information System (INIS)

    Zhang, Y.J.; Yang, J.

    2014-01-01

    Multi-walled carbon nanotubes (CNTs) were modified by oxidation with sodium hypochlorite (NaClO) solutions and were employed as adsorbents to study the adsorption characteristics of copper ions from water. The results show that adsorption capacity of CNTs treated by NaClO solution can be greatly enhanced. The adsorption capacity of Cu2+ on as received and modified CNTs increased with the increase of pH and CNTs mass, but it decreased with the temperature. Experimental data also indicated that the adsorption process could achieve equilibrium within 40 min. Both Langmuir and Freundlich isotherm models fitted the experimental data very well. According to the Langmuir model the maximum copper ions adsorption uptake onto modified CNTs was determined as 40.00 mg/g. Our results suggest that CNTs have profound potential application in environmental protection. (author)

  8. Multi Objective Optimization of Multi Wall Carbon Nanotube Based Nanogrinding Wheel Using Grey Relational and Regression Analysis

    Science.gov (United States)

    Sethuramalingam, Prabhu; Vinayagam, Babu Kupusamy

    2016-07-01

    Carbon nanotube mixed grinding wheel is used in the grinding process to analyze the surface characteristics of AISI D2 tool steel material. Till now no work has been carried out using carbon nanotube based grinding wheel. Carbon nanotube based grinding wheel has excellent thermal conductivity and good mechanical properties which are used to improve the surface finish of the workpiece. In the present study, the multi response optimization of process parameters like surface roughness and metal removal rate of grinding process of single wall carbon nanotube (CNT) in mixed cutting fluids is undertaken using orthogonal array with grey relational analysis. Experiments are performed with designated grinding conditions obtained using the L9 orthogonal array. Based on the results of the grey relational analysis, a set of optimum grinding parameters is obtained. Using the analysis of variance approach the significant machining parameters are found. Empirical model for the prediction of output parameters has been developed using regression analysis and the results are compared empirically, for conditions of with and without CNT grinding wheel in grinding process.

  9. Systemic and immunotoxicity of pristine and PEGylated multi-walled carbon nanotubes in an intravenous 28 days repeated dose toxicity study

    Directory of Open Access Journals (Sweden)

    Zhang T

    2017-02-01

    Full Text Available Ting Zhang,1–3 Meng Tang,1–3 Shanshan Zhang,1–3 Yuanyuan Hu,1–3 Han Li,4 Tao Zhang,4 Yuying Xue,1–3 Yuepu Pu1–3 1Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, China; 2Jiangsu key Laboratory for Biomaterials and Devices, Southeast University, Nanjing, China; 3Collaborative Innovation Center of Suzhou Nano Science and Technology, Suzhou, China; 4Department of Material Science and Engineering, National Key Laboratory of Solid State Microstructures, Nanjing University, Nanjing, China Abstract: The numerous increasing use of carbon nanotubes (CNTs derived from nanotechnology has raised concerns about their biosafety and potential toxicity. CNTs cause immunologic dysfunction and limit the application of CNTs in biomedicine. The immunological responses induced by pristine multi-walled carbon nanotubes (p-MWCNTs and PEGylated multi-walled carbon nanotubes (MWCNTs-PEG on BALB/c mice via an intravenous administration were investigated. The results reflect that the p-MWCNTs induced significant increases in spleen, thymus, and lung weight. Mice treated with p-MWCNTs showed altered lymphocyte populations (CD3+, CD4+, CD8+, and CD19+ in peripheral blood and increased serum IgM and IgG levels, and splenic macrophage ultrastructure indicated mitochondria swelling. p-MWCNTs inhibited humoral and cellular immunity function and were associated with decreased immune responses against sheep erythrocytes and serum hemolysis level. Natural killer (NK activity was not modified by two types of MWCNTs. In comparison with two types of MWCNTs, for a same dose, p-MWCNTs caused higher levels of inflammation and immunosuppression than MWCNTs-PEG. The results of immunological function suggested that after intravenous administration with p-MWCNTs caused more damage to systemic immunity than MWCNTs- PEG. Here, we demonstrated that a surface functional modification on MWCNTs reduces

  10. Diurnal thermal analysis of microencapsulated PCM-concrete composite walls

    International Nuclear Information System (INIS)

    Thiele, Alexander M.; Sant, Gaurav; Pilon, Laurent

    2015-01-01

    Highlights: • Transient heat conduction across microencapsulated PCM-concrete walls was simulated. • Equivalent homogeneous wall with effective thermal properties was rigorously derived. • Adding PCM to the wall increases daily energy savings and delays peak thermal load. • Energy savings is maximum when PCM melting temperature equals indoor temperature. • Energy savings are limited in extreme climates but time delay can be large. - Abstract: This paper examines the benefits of adding microencapsulated phase change material (PCM) to concrete used in building envelopes to reduce energy consumption and costs. First, it establishes that the time-dependent thermal behavior of microencapsulated PCM-concrete composite walls can be accurately predicted by an equivalent homogeneous wall with appropriate effective thermal properties. The results demonstrate that adding microencapsulated PCM to concrete resulted in a reduction and a time-shift in the maximum heat flux through the composite wall subjected to diurnal sinusoidal outdoor temperature and solar radiation heat flux. The effects of the PCM volume fraction, latent heat of fusion, phase change temperature and temperature window, and outdoor temperature were evaluated. Several design rules were established including (i) increasing the PCM volume fraction and/or enthalpy of phase change increased the energy flux reduction and the time delay, (ii) the energy flux reduction was maximized when the PCM phase change temperature was close to the desired indoor temperature, (iii) the optimum phase change temperature to maximize the time delay increased with increasing average outdoor temperature, (iv) in extremely hot or cold climates, the thermal load could be delayed even though the reduction in daily energy flux was small, and (v) the choice of phase change temperature window had little effect on the energy flux reduction and on the time delay. This analysis can serve as a framework to design PCM composite walls

  11. Design of lightweight multi-material automotive bodies using new material performance indices of thin-walled beams for the material selection with crashworthiness consideration

    International Nuclear Information System (INIS)

    Cui, Xintao; Zhang, Hongwei; Wang, Shuxin; Zhang, Lianhong; Ko, Jeonghan

    2011-01-01

    Currently, automotive bodies are constructed usually using a single material, e.g. steel or aluminum. Compared to single-material automotive bodies, multi-material automotive bodies allow optimal material selection in each structural component for higher product performance and lower cost. This paper presents novel material performance indices and procedures developed to guide systematic material selection for multi-material automotive bodies. These new indices enable to characterize the crashworthiness performance of complex-shaped thin-walled beams in multi-material automotive bodies according to material types. This paper also illustrates the application of these performance indices and procedures by designing a lightweight multi-material automotive body. These procedures will help to design a lightweight and affordable body favored by the automotive industry, thus to reduce fuel consumption and greenhouse gas emissions.

  12. Windows 2012 Server network security securing your Windows network systems and infrastructure

    CERN Document Server

    Rountree, Derrick

    2013-01-01

    Windows 2012 Server Network Security provides the most in-depth guide to deploying and maintaining a secure Windows network. The book drills down into all the new features of Windows 2012 and provides practical, hands-on methods for securing your Windows systems networks, including: Secure remote access Network vulnerabilities and mitigations DHCP installations configuration MAC filtering DNS server security WINS installation configuration Securing wired and wireless connections Windows personal firewall

  13. Windows 8.1 bible

    CERN Document Server

    Boyce, Jim; Tidrow, Rob

    2014-01-01

    Windows 8.1 coverage that goes above and beyond all competitors? Serving as an evolutionary update to Windows 8, Windows 8.1 provides critical changes to parts of Windows 8, such as greater customization of the interface and boot operations, return of a 'start button' that reveals apps, greater integration between the two interfaces, and updates to apps. Weighing in at nearly 1000 pages, Windows 8.1 Bible provides deeper Windows insight than any other book on the market. It's valuable for both professionals needing a guide to the nooks and crannies of Windows and regular users wanting a wide

  14. Automated image segmentation and registration of vessel wall MRI for quantitative assessment of carotid artery vessel wall dimensions and plaque composition

    NARCIS (Netherlands)

    Klooster, Ronald van 't

    2014-01-01

    The main goal of this thesis was to develop methods for automated segmentation, registration and classification of the carotid artery vessel wall and plaque components using multi-sequence MR vessel wall images to assess atherosclerosis. First, a general introduction into atherosclerosis and

  15. MultiSpec—a tool for multispectral hyperspectral image data analysis

    Science.gov (United States)

    Biehl, Larry; Landgrebe, David

    2002-12-01

    MultiSpec is a multispectral image data analysis software application. It is intended to provide a fast, easy-to-use means for analysis of multispectral image data, such as that from the Landsat, SPOT, MODIS or IKONOS series of Earth observational satellites, hyperspectral data such as that from the Airborne Visible-Infrared Imaging Spectrometer (AVIRIS) and EO-1 Hyperion satellite system or the data that will be produced by the next generation of Earth observational sensors. The primary purpose for the system was to make new, otherwise complex analysis tools available to the general Earth science community. It has also found use in displaying and analyzing many other types of non-space related digital imagery, such as medical image data and in K-12 and university level educational activities. MultiSpec has been implemented for both the Apple Macintosh ® and Microsoft Windows ® operating systems (OS). The effort was first begun on the Macintosh OS in 1988. The GLOBE ( http://www.globe.gov) program supported the development of a subset of MultiSpec for the Windows OS in 1995. Since then most (but not all) of the features in the Macintosh OS version have been ported to the Windows OS version. Although copyrighted, MultiSpec with its documentation is distributed without charge. The Macintosh and Windows versions and documentation on its use are available from the World Wide Web at URL: http://dynamo.ecn.purdue.edu/˜biehl/MultiSpec/ MultiSpec is copyrighted (1991-2001) by Purdue Research Foundation, West Lafayette, Indiana 47907.

  16. Effect of porosity variation on the electrochemical behavior of vertically aligned multi-walled carbon nanotubes.

    Science.gov (United States)

    Raut, Akshay S; Parker, Charles B; Stoner, Brian R; Glass, Jeffrey T

    2012-06-01

    Electrochemical charge storage characteristics of vertically aligned multi-walled carbon nanotubes (MWCNTs) as a function of varying diameter and spacing are reported. It was observed that the specific capacitance of the MWCNTs increased as both diameter and inter-tube spacing decreased. The MWCNT films with 229 nm inter-MWCNT spacing exhibited specific capacitance of 228 F/g versus 70 F/g for 506 nm spacing, when tested in a non-aqueous electrolyte. Further, a trend in specific capacitance versus pore size is proposed. Coupled with previously reported trends observed in the sub-10 nm pore size regime, this is expected to offer better understanding of electrochemical behavior of porous carbon materials over a wide range of pore sizes.

  17. Wall-cooling-induced mixed-convection flow recirculation in a vertical square-array multi-rod channel

    International Nuclear Information System (INIS)

    Luangdilok, W.; Todreas, N.E.

    1989-01-01

    This work investigated the structure of penetrative flow recirculation and associated flow conditions in a multi-rod channel induced by interassembly heat transfer that causes cooling through channel walls. Three investigation approaches, experimental, numerical, and analytical were employed in a complimentary fashion. Physical experiments involved water flow visualization and temperature measurement in a 4x4 rod square channel. Numerical experiments involved 3-dimensional simulations of water and sodium flow in a 2x2-rod channels. An approximate reverse flow model including Prandtl number effect was developed. A correlating equation based on the model and experiments was verified for water to correctly predict the trend of the 4x4-rod experimental penetration depth data. (orig.)

  18. Cobalt hexacyanoferrate modified multi-walled carbon nanotubes/graphite composite electrode as electrochemical sensor on microfluidic chip

    International Nuclear Information System (INIS)

    Li Xinchun; Chen Zuanguang; Zhong Yuwen; Yang Fan; Pan Jianbin; Liang Yajing

    2012-01-01

    Highlights: ► CoHCF nanoparticles modified MWCNTs/graphite electrode use for electrochemistry on electrophoresis microchip for the first time. ► Simultaneous, rapid, and sensitive electrochemical detection of hydrazine and isoniazid in real samples. ► An exemplary work of CME sensor assembly onto microchip for determination of analytes with environmental significance. ► Manifestation of the applicability and flexibility of CME sensor for electroanalysis on microfluidic chip. - Abstract: Nanomaterial-based electrochemical sensor has received significant interest. In this work, cobalt hexacyanoferrate modified multi-walled carbon nanotubes/graphite composite electrode was electrochemically prepared and exploited as an amperometric detector for microchip electrophoresis. The prepared sensor displayed rapid and sensitive response towards hydrazine and isoniazid oxidation, which was attributed to synergetic electrocatalytic effect of cobalt hexacyanoferrate and multi-walled carbon nanotubes. The sensitivity enhancement with nearly two orders of magnitude was gained, compared with the bare carbon paste electrode, with the detection limit of 0.91 μM (S/N = 3) for hydrazine. Acceptable repeatability of the microanalysis system was verified by consecutive eleven injections of hydrazine without chip and electrode treatments, the RSDs for peak current and migration time were 3.4% and 2.1%, respectively. Meanwhile, well-shaped electrophoretic peaks were observed, mainly due to fast electron transfer of electroactive species on the modified electrode. The developed microchip-electrochemistry setup was successfully applied to the determination of hydrazine and isoniazid in river water and pharmaceutical preparation, respectively. Several merits of the novel electrochemical sensor coupled with microfluidic platform, such as comparative stability, easy fabrication and high sensitivity, hold great potential for hydrazine compounds assay in the lab-on-a-chip system.

  19. Application of Energy Window Concept in Doppler Broadening of {sup 238}U Cross Section

    Energy Technology Data Exchange (ETDEWEB)

    Khassnov, Azamat; Choi, Soo Young; Lee, Deok Jung [Ulsan National Institute of Science and Technology, Ulsan (Korea, Republic of)

    2014-10-15

    Currently, the NJOY code is used for construction and Doppler broadening of microscopic cross sections. There exist several methods or formalisms to produce microscopic cross sections and there are also different methods of Doppler broadening. In this paper, Multi-Level Breit-Wigner (MLBW) formalism and the Psi method are used for generation and Doppler broadening of the resonance cross section. Accuracy of the energy window concept applied MLBW (EW MLBW) Doppler broadened cross section was compared with that of the cross section generated by conventional MLBW (Con MLBW) formalism for {sup 2}38U isotope using MATLAB. The conventional method requires Doppler broadening of all resonances, including resonances far from the target energy point, which do not change much with respect to the temperature change. The energy window concept makes Doppler broadening possible with a smaller number of resonances neighboring to the energy point we are interested in, and just adds up 0 K temperature cross sections of other resonances. Multi-level Breit-Wigner formalism and the Doppler broadening method were used to construct microscopic cross sections of {sup 238}U at different temperatures. The energy window concept was applied only for the 1st resonance energy region (4.5∼11.2 eV). The energy window concept demonstrates high competitiveness because the relative differences were less than 0.0016% for all types of cross sections. The advantage of the energy window concept is that the number of resonances broadened for every energy point is significantly reduced, which allows a reduction of computation time by almost 45 % of Doppler broadening time of the cross section generation at temperatures higher than 0 K.

  20. Improved field emission from indium decorated multi-walled carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Sreekanth, M.; Ghosh, S., E-mail: santanu1@physics.iitd.ernet.in; Biswas, P.; Kumar, S.; Srivastava, P.

    2016-10-15

    Graphical abstract: Improved field emission properties have been achieved for Indium (In) decorated MWCNTs and are shown using the schematic of field emission set up with In/CNT cathode, and a plot of J-E characteristics for pristine and In decorated CNTs. - Highlights: • Field emission (FE) properties have been studied for the first time from Indium (In) decorated MWCNT films. • Observed increased density of states near the Fermi level for In decorated films. • Superior field emission properties have been achieved for In decorated CNT films. - Abstract: Multi-walled carbon nanotube (MWCNT) films were grown using thermal chemical vapor deposition (T-CVD) process and were decorated with indium metal particles by thermal evaporation technique. The In metal particles are found to get oxidized. The In decorated films show 250% enhancement in the FE current density, lower turn-on and threshold fields, and better temporal stability as compared to their undecorated counterpart. This improvement in field emission properties is primarily attributed to increased density of states near the Fermi level. The presence of O 2p states along with a small contribution from In 5s states results in the enhancement of density of states in the vicinity of the Fermi level.

  1. Preparation of Multi-walled Carbon Nano tubes/ Natural Rubber Composite by Wet Mixing Method

    International Nuclear Information System (INIS)

    Azira Abdul Aziz; Azira Abdul Aziz; Che Su Mat Saad; Mohamad Rusop Mahmood

    2011-01-01

    Natural rubber/multi-walled carbon nano tubes (Nr/MWCNTs) nanocomposite is formed by incorporating nano tubes in a polymer solution and subsequently evaporating the solvent. Using this technique, nano tubes will be dispersed homogeneously in the NR matrix in an attempt to increase the mechanical properties of these nano composites. Mechanical test results show an increase in the tensile strength for up to 19 times in relation to pure NR. In addition to mechanical testing, the morphology of the MWNTs into NR was studied by Field Emission Scanning Electron Microscopy (FESEM) in order to understand the morphology of the resulting system. Slight shift noted from Raman analyses from each different wt. % of MWCNTs with the NR due to the stress transfer that indicates reinforcement of the nano tubes. (author)

  2. Highly conductive, transparent flexible films based on open rings of multi-walled carbon nanotubes

    International Nuclear Information System (INIS)

    Ko, Wen-Yin; Su, Jun-Wei; Guo, Chian-Hua; Fu, Shu-Juan; Hsu, Chuen-Yuan; Lin, Kuan-Jiuh

    2011-01-01

    Open rings of multi-walled carbon nanotubes were stacked to form porous networks on a poly(ethylene terephthalate) substrate to form a flexible conducting film (MWCNT-PET) with good electrical conductivity and transparency by a combination of ultrasonic atomization and spin-coating technique. To enhance the electric flexibility, we spin-coated a cast film of poly(vinyl alcohol) onto the MWCNT-PET substrate, which then underwent a thermo-compression process. Field-emission scanning electron microscopy of the cross-sectional morphology illustrates that the film has a robust network with a thickness of ∼ 175 nm, and it remarkably exhibits a sheet resistance of approximately 370 Ω/sq with ∼ 77% transmittance at 550 nm even after 500 bending cycles. This electrical conductivity is much superior to that of other MWCNT-based transparent flexible films.

  3. Multi-Walled Carbon Nanotube-Assisted Electrodeposition of Silver Dendrite Coating as a Catalytic Film

    Directory of Open Access Journals (Sweden)

    Li Fu

    2017-12-01

    Full Text Available A multi-walled carbon nanotube (MWCNT-coated indium tin oxide (ITO slide was used as a platform for the growth of a silver dendrite (Ag-D film using cyclic voltammetry. The particular dendritic nanostructures were formed by the diffusion-limited-aggregation model due to the potential difference between the MWCNTs and the ITO surface. The Ag-D-coated ITO film was then used for the catalytic degradation of methyl orange (MO and methylene blue (MB under static aqueous conditions. The network structure of the Ag-D allows the efficient diffusion of MO and MB, and consequently enhances the catalytic performance. Since the thin film is much easier to use for the post-treatment of powder catalysts, the proposed method shows great potential in many catalytic applications.

  4. A new method of functionalized multi walled carbon nanotubes by natural oil for microorganism cells detection

    Science.gov (United States)

    Haider, Adawiya J.; Marzoog, Thorria R.; Hadi, Iman H.; Jameel, Zainab N.

    2018-05-01

    In this work, new surfactants for Functionalization of Multi Walled Carbon Nanotubes (F-MWCNTs) with functional groups have been developed by using walnut oil, to improve their surface activity (solubility) and a create free reticules (functional groups) on it. MWCNTs were functionalized with walnut oil via ultra-sonication technique at 25°C for 1h with no drastic fragmentation of MWCNTs. Fourier Transformed Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), High Resolution Transmission Electron Microscopy (HRTEM) and have been employed for the characterizations and analysis. In addition, the antibacterial activity of functionalized MWCNTs against Gram negative. Escherichia coli (E. coli) and Gram positive Staphylococcus aureus (S. aureus) bacteria are examined.

  5. Gold nanoparticle/multi-walled carbon nanotube modified glassy carbon electrode as a sensitive voltammetric sensor for the determination of diclofenac sodium.

    Science.gov (United States)

    Afkhami, Abbas; Bahiraei, Atousa; Madrakian, Tayyebeh

    2016-02-01

    A simple and highly sensitive sensor for the determination of diclofenac sodium based on gold nanoparticle/multi-walled carbon nanotube modified glassy carbon electrode is reported. Scanning electron microscopy along with energy dispersive X-ray spectroscopy, electrochemical impedance spectroscopy, cyclic voltammetry and square wave voltammetry was used to characterize the nanostructure and performance of the sensor and the results were compared with those obtained at the multi-walled carbon nanotube modified glassy carbon electrode and bare glassy carbon electrode. Under the optimized experimental conditions diclofenac sodium gave linear response over the range of 0.03-200μmolL(-1). The lower detection limits were found to be 0.02μmolL(-1). The effect of common interferences on the current response of DS was investigated. The practical application of the modified electrode was demonstrated by measuring the concentration of diclofenac sodium in urine and pharmaceutical samples. This revealed that the gold nanoparticle/multiwalled carbon nanotube modified glassy carbon electrode shows excellent analytical performance for the determination of diclofenac sodium in terms of a very low detection limit, high sensitivity, very good accuracy, repeatability and reproducibility. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Building a Lego wall: Sequential action selection.

    Science.gov (United States)

    Arnold, Amy; Wing, Alan M; Rotshtein, Pia

    2017-05-01

    The present study draws together two distinct lines of enquiry into the selection and control of sequential action: motor sequence production and action selection in everyday tasks. Participants were asked to build 2 different Lego walls. The walls were designed to have hierarchical structures with shared and dissociated colors and spatial components. Participants built 1 wall at a time, under low and high load cognitive states. Selection times for correctly completed trials were measured using 3-dimensional motion tracking. The paradigm enabled precise measurement of the timing of actions, while using real objects to create an end product. The experiment demonstrated that action selection was slowed at decision boundary points, relative to boundaries where no between-wall decision was required. Decision points also affected selection time prior to the actual selection window. Dual-task conditions increased selection errors. Errors mostly occurred at boundaries between chunks and especially when these required decisions. The data support hierarchical control of sequenced behavior. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  7. Visible and near-infrared radiative properties of vertically aligned multi-walled carbon nanotubes

    International Nuclear Information System (INIS)

    Wang, X J; Zhang, Z M; Flicker, J D; Ready, W J; Lee, B J

    2009-01-01

    This work investigates the reflection and scattering from vertically aligned carbon nanotubes, fabricated on silicon substrate using thermally enhanced chemical vapor deposition with both tip-growth and base-growth mechanisms. The directional-hemispherical reflectance in the visible and near-infrared wavelengths was measured with an integrating sphere. The polarization-dependent bidirectional reflectance distribution function was characterized with a laser scatterometer at the wavelength of 635 nm. The effective medium theory was used to elucidate the mechanism of high absorptance (greater than 0.97 in the spectral region from 400 to 1800 nm) of the multi-walled carbon nanotube samples. It is observed that scattering by impurities on the top of the nanotubes, by the nanotube tips, and by defects and misalignment can significantly increase the reflectance and introduce retroreflection. This study may facilitate application of carbon nanotubes in pyroelectric detectors as well as thermophotovoltaic emitters and absorbers.

  8. Synthesis and characteristics of Fe-filled multi-walled carbon nanotubes for biomedical application

    Energy Technology Data Exchange (ETDEWEB)

    Moench, I [Leibniz Institute of Solid State and Materials Research Dresden, IFW-Dresden, Helmholtzstr. 20, D-01069 Dresden (Germany); Leonhardt, A [Leibniz Institute of Solid State and Materials Research Dresden, IFW-Dresden, Helmholtzstr. 20, D-01069 Dresden (Germany); Meye, A [Department of Urology, Technical University Dresden, Fetscherstrasse 74, D-01062 Dresden (Germany); Hampel, S [Leibniz Institute of Solid State and Materials Research Dresden, IFW-Dresden, Helmholtzstr. 20, D-01069 Dresden (Germany); Kozhuharova-Koseva, R [Leibniz Institute of Solid State and Materials Research Dresden, IFW-Dresden, Helmholtzstr. 20, D-01069 Dresden (Germany); Elefant, D [Leibniz Institute of Solid State and Materials Research Dresden, IFW-Dresden, Helmholtzstr. 20, D-01069 Dresden (Germany); Wirth, M P [Department of Urology, Technical University Dresden, Fetscherstrasse 74, D-01062 Dresden (Germany); Buechner, B [Leibniz Institute of Solid State and Materials Research Dresden, IFW-Dresden, Helmholtzstr. 20, D-01069 Dresden (Germany)

    2007-04-15

    Multifunctional nanocontainers can be produced based on partially filled Fe-multi walled carbon nanotubes (MWCNTs). Using thermal decomposition ferrocene filled nanotubes can be grown aligned on substrates. The encapsulated metal nanowires have diameters of 5-30 nm and a length up to few microns. They consist of single-crystalline of {alpha} and {gamma}-Fe- phases. Using heat treatment, it is possible to transform {gamma}-Fe into {alpha}-Fe. With the aid of wet chemical methods the nanotubes can be opened and additionally filled with an agent, e.g., therapeutic agents (carboplatin) or other metals (copper). Initial studies do not show a high toxicity over a period of 440 days. These materials can be used for drug delivery and hyperthermia. The specific absorption rate (SAR) is greater than 100W/(g-{alpha}-Fe) in a magnetic field of 18kA/m (f = 250kHz)

  9. Bonding titanium on multi-walled carbon nanotubes for hydrogen storage: An electrochemical approach

    Energy Technology Data Exchange (ETDEWEB)

    Brieno-Enriquez, K.M.; Ledesma-Garcia, J. [Centro de Investigacion y Desarrollo Tecnologico en Electroquimica, S.C., Parque Tecnologico Queretaro-Sanfandila, Pedro Escobedo, Qro, C.P. 76703 (Mexico); Perez-Bueno, J.J., E-mail: jperez@cideteq.mx [Centro de Investigacion y Desarrollo Tecnologico en Electroquimica, S.C., Parque Tecnologico Queretaro-Sanfandila, Pedro Escobedo, Qro, C.P. 76703 (Mexico); Godinez, Luis A. [Centro de Investigacion y Desarrollo Tecnologico en Electroquimica, S.C., Parque Tecnologico Queretaro-Sanfandila, Pedro Escobedo, Qro, C.P. 76703 (Mexico); Terrones, H. [Instituto Potosino de Investigacion Cientifica y Tecnologica, Division de Materiales Avanzados, Camino a la Presa San Jose 2055, Col. Lomas 4o Seccion C.P. 78216, San Luis Potosi (Mexico); Angeles-Chavez, C. [Instituto Mexicano del Petroleo, Programa de Ingenieria Molecular, Eje Central Lazaro Cardenas 152, A.P. 14-805, 07730 Mexico D.F. (Mexico)

    2009-06-15

    This work explores the use of some procedures, involving electrochemistry, in order to bond atomic Ti on the outer surface of multi-walled carbon nanotubes (MWNTs). It is assumed that each titanium atom has the potential of host up to four hydrogen molecules and relinquish them by heated. As a way to spread and stick nanotubes on an electrode, a tested route was drying a solution with nanotubes on a glassy carbon flat electrode. The MWNTs were treated by anodic polarization in organic media. Dichloromethane was selected as the medium and titanium tetrachloride as the precursor for attaching atomic Ti onto the nanotubes. The hydrogen adsorption, estimated from voltamperometry was five times higher on Ti-MWNTs that on bare nanotubes. The use of anodic polarization during the preparation of Ti-MWNTs may represent great significance in procedure, which was manifest during the voltamperometric evaluation of samples.

  10. Simple quantification of surface carboxylic acids on chemically oxidized multi-walled carbon nanotubes

    Science.gov (United States)

    Gong, Hyejin; Kim, Seong-Taek; Lee, Jong Doo; Yim, Sanggyu

    2013-02-01

    The surface of multi-walled carbon nanotube (MWCNT) was chemically oxidized using nitric acid and sulfuric-nitric acid mixtures. Thermogravimetric analysis, transmission electron microscopy and infrared spectroscopy revealed that the use of acid mixtures led to higher degree of oxidation. More quantitative identification of surface carboxylic acids was carried out using X-ray photoelectron spectroscopy (XPS) and acid-base titration. However, these techniques are costly and require very long analysis times to promptly respond to the extent of the reaction. We propose a much simpler method using pH measurements and pre-determined pKa value in order to estimate the concentration of carboxylic acids on the oxidized MWCNT surfaces. The results from this technique were consistent with those obtained from XPS and titration, and it is expected that this simple quantification method can provide a cheap and fast way to monitor and control the oxidation reaction of MWCNT.

  11. γ-Fe_2O_3 magnetic nanoparticle functionalized with carboxylated multi walled carbon nanotube: Synthesis, characterization, analytical and biomedical application

    International Nuclear Information System (INIS)

    Kılınç, Ersin

    2016-01-01

    In recent years, magnetic nanoparticles attained special interest in nanobiotechnology and nanomedicine due to their uniqe properties and biocompatibilities. From this perspective, hybride nanostructure composed from γ-Fe_2O_3 magnetic nanoparticle and carboxylated multi walled carbon nanotube was synthesized and characterized by FT-IR, VSM, SEM, HR-TEM and ICP-OES. Microscopy images showed that magnetic nanoparticles were nearly spherical structure that arranged on the axis of carboxylated MWCNT. Particle size was found lower than 10 nm. VSM results showed that the obtained magnetic nanoparticles presented superparamagnetic properties at room temperature. The magnetic saturation value was determined as 35.2 emu/g. It was used for the adsorption and controlled release of harmane, a potent tremor-producing neurotoxin. Maximum adsorption capacity was calculated as 151.5 mg/g from Langmuir isotherm. Concentration of harmane was determined by HPLC with fluorescence detection. The antimicrobial activity of synthesized magnetic nanoparticle was investigated against gram-negative and gram-positive bacteria. However, no activity was observed. - Highlights: • A nanomaterial from gamma iron oxide and multi walled carbon nanotube was synthesized. • It was characterized and microstructure was investigated. • No antimicrobial activity was observed. • Adsorption and release of harmane on its were examined.

  12. Designing tough and fracture resistant polypropylene/multi wall carbon nanotubes nanocomposites by controlling stereo-complexity and dispersion morphology

    International Nuclear Information System (INIS)

    Das, Dibyendu; Satapathy, Bhabani K.

    2014-01-01

    Highlights: • New pathway to improve dispersion and toughness by tacticity modification. • >330% toughness enhancement in PP/MWCNT nanocomposites with stereo-complex PP. • Prominent dispersion and distribution morphology due to matrix stereocomplexity. • Tacticity induced “Semi-ductile-to-tough-to-quasi-brittle” transitions in the PP/MWCNT. • Two-fold reduced steady state CTOD rate in i-PP+s-PP/ MWCNT nanocomposites. - Abstract: A remarkable toughness enhancement (>330%) of multi wall carbon nanotubes (MWCNT) filled stereo-complex polypropylene (PP) matrix i.e. blend of isotactic-PP and syndiotactic-PP (70:30) with differences in stereo-regularity has been observed. The enhancement has been correlated to quantifiable morphological parameters such as free-space lengths concerning dispersion and relatively greater reduction in crystallite size/lamellar thickness. Systematic analysis of glass transition data and estimation of multi wall carbon nanotubes induced reduction in interfacial polymer chain immobilization reiterates susceptibility of polymer segments to ready-mobility. The extent of toughening has quantitatively been analyzed by fracture-energy partitioning, essential work of fracture (EWF), approach enabling the detection of a “semi-ductile-to-tough-to-quasi-brittle” transition in the MWCNT filled stereo-complex polypropylene. Real-time fracture kinetics analysis revealed toughening mechanism to be primarily blunting-assisted; an aspect also corroborated by extensive plastic flow without much energy dissipation in the inner fracture process zone. Thus the study establishes a new pathway of tacticity-defined matrix modification to toughen nanocomposites

  13. Analysis of multi-wall carbon nanotube based porous Li battery electrodes’ using TOF-SIMS ion imaging

    International Nuclear Information System (INIS)

    Karar, N.; Singh, B.P.; Elizabeth, Indu

    2015-01-01

    Highlights: • Usage of MWCNT material for Li battery electrode. • LiPF 6 as electrolyte material. • Charging and discharging cycles of the battery and their effect on the electrode and electrolyte material. • TOF-SIMS ion imaging based analysis of the effects of the charging discharging cycles on the materials. • Effects of multi-atomic molecules. - Abstract: Li ion batteries and its accessories are now under increased focus of research due to enhanced energy storage and recycling requirements and the need for clean environments. In this context, observations on Li battery electrodes prepared using multi-wall carbon nanotubes (MWCNT) coated on stainless steel as observed by time of flight secondary ion mass spectrometry (TOF-SIMS) analysis and their relevance in understanding and improving the electrochemical properties of such battery systems are discussed. Porosity issues due to MWCNT, and accumulation of chemical residues with operational cycles were observed, their possible causes were also analyzed and discussed. Issues on change in electrode performance due to usage of tin oxide coatings on the MWCNT were also compared and analyzed

  14. Efficient Windows Collaborative

    Energy Technology Data Exchange (ETDEWEB)

    Nils Petermann

    2010-02-28

    The project goals covered both the residential and commercial windows markets and involved a range of audiences such as window manufacturers, builders, homeowners, design professionals, utilities, and public agencies. Essential goals included: (1) Creation of 'Master Toolkits' of information that integrate diverse tools, rating systems, and incentive programs, customized for key audiences such as window manufacturers, design professionals, and utility programs. (2) Delivery of education and outreach programs to multiple audiences through conference presentations, publication of articles for builders and other industry professionals, and targeted dissemination of efficient window curricula to professionals and students. (3) Design and implementation of mechanisms to encourage and track sales of more efficient products through the existing Window Products Database as an incentive for manufacturers to improve products and participate in programs such as NFRC and ENERGY STAR. (4) Development of utility incentive programs to promote more efficient residential and commercial windows. Partnership with regional and local entities on the development of programs and customized information to move the market toward the highest performing products. An overarching project goal was to ensure that different audiences adopt and use the developed information, design and promotion tools and thus increase the market penetration of energy efficient fenestration products. In particular, a crucial success criterion was to move gas and electric utilities to increase the promotion of energy efficient windows through demand side management programs as an important step toward increasing the market share of energy efficient windows.

  15. A multi-component parallel-plate flow chamber system for studying the effect of exercise-induced wall shear stress on endothelial cells.

    Science.gov (United States)

    Wang, Yan-Xia; Xiang, Cheng; Liu, Bo; Zhu, Yong; Luan, Yong; Liu, Shu-Tian; Qin, Kai-Rong

    2016-12-28

    In vivo studies have demonstrated that reasonable exercise training can improve endothelial function. To confirm the key role of wall shear stress induced by exercise on endothelial cells, and to understand how wall shear stress affects the structure and the function of endothelial cells, it is crucial to design and fabricate an in vitro multi-component parallel-plate flow chamber system which can closely replicate exercise-induced wall shear stress waveforms in artery. The in vivo wall shear stress waveforms from the common carotid artery of a healthy volunteer in resting and immediately after 30 min acute aerobic cycling exercise were first calculated by measuring the inner diameter and the center-line blood flow velocity with a color Doppler ultrasound. According to the above in vivo wall shear stress waveforms, we designed and fabricated a parallel-plate flow chamber system with appropriate components based on a lumped parameter hemodynamics model. To validate the feasibility of this system, human umbilical vein endothelial cells (HUVECs) line were cultured within the parallel-plate flow chamber under abovementioned two types of wall shear stress waveforms and the intracellular actin microfilaments and nitric oxide (NO) production level were evaluated using fluorescence microscope. Our results show that the trends of resting and exercise-induced wall shear stress waveforms, especially the maximal, minimal and mean wall shear stress as well as oscillatory shear index, generated by the parallel-plate flow chamber system are similar to those acquired from the common carotid artery. In addition, the cellular experiments demonstrate that the actin microfilaments and the production of NO within cells exposed to the two different wall shear stress waveforms exhibit different dynamic behaviors; there are larger numbers of actin microfilaments and higher level NO in cells exposed in exercise-induced wall shear stress condition than resting wall shear stress condition

  16. Plasma focus as an x-ray source for tailoring of radiation in different energy windows

    International Nuclear Information System (INIS)

    Zakaullah, M.; Alamgir, K.; Shafiq, M.; Sharif, M.

    2001-01-01

    A low energy (2.3 kj) plasma focus energized by a single 32 micro f capacitor charged at 12 kv with filling gases hydrogen, neon and argon is investigated as an X-ray source. Experiments are conducted with a copper and an aluminum anode. Specifically, attention in given to tailoring the radiation in different windows, e. g. 1.2-1.3 keV, 1.3-1.5 keV, 2.5-5 keV and Cu-Ka line radiation. The highest X-ray emission is observed with neon filling and the copper anode in the 1.2-1.3 keV window, which speculated to be generated due to recombination of hydrogen like neon ions with a few eV to a few 10s of eV electrons. The wall-plug efficiency of the device is found to be 4%. The other significant emission occurs with Hydrogen filling, which exhibits wall plug efficiency of 1.7% for over all x-ray emission and 0.35% for Cu- Ka line radiation. The emission is dominated by the interaction of electrons in the current sheath with the anode tip. The emission with the aluminum anode and hydrogen filling is up to 10 j, which corresponds to wall-plug efficiency of 0.4%. The X-ray emission with argon filling is less significant. (author)

  17. Wall shear stress characterization of a 3D bluff-body separated flow

    Science.gov (United States)

    Fourrié, Grégoire; Keirsbulck, Laurent; Labraga, Larbi

    2013-10-01

    Efficient flow control strategies aimed at reducing the aerodynamic drag of road vehicles require a detailed knowledge of the reference flow. In this work, the flow around the rear slanted window of a generic car model was experimentally studied through wall shear stress measurements using an electrochemical method. The mean and fluctuating wall shear stress within the wall impact regions of the recirculation bubble and the main longitudinal vortex structures which develop above the rear window are presented. Correlations allow a more detailed characterization of the recirculation phenomenon within the separation bubble. In the model symmetry plane the recirculation structure compares well with simpler 2D configurations; specific lengths, flapping motion and shedding of large-scale vortices are observed, these similarities diminish when leaving the middle plane due to the strong three-dimensionality of the flow. A specific attention is paid to the convection processes occurring within the recirculation: a downstream convection velocity is observed, in accordance with 2D recirculations from the literature, and an upstream convection is highlighted along the entire bubble length which has not been underlined in some previous canonical configurations.

  18. Windows 10 for dummies

    CERN Document Server

    Rathbone, Andy

    2015-01-01

    The fast and easy way to get up and running with Windows 10 Windows 10 For Dummies covers the latest version of Windows and gets you up and running with the changes and new features you'll find in this updated operating system. Packed with time-saving tips to help you get the most out of the software, this helpful Windows 10 guide shows you how to manage Windows tasks like navigating the interface with a mouse or touchscreen, connecting to the web, and troubleshooting problems and making quick fixes. Assuming no prior knowledge of the software, Windows 10 For Dummies addresses the updates to

  19. Provide Views | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  20. Reduced Fading | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  1. EWC Members | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  2. Visible Transmittance | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  3. Gas Fills | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  4. EWC Membership | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  5. Reducing Condensation | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  6. Improved Comfort | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  7. Financing & Incentives | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  8. Tools & Resources | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  9. Books & Publications | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  10. Design Considerations | Efficient Windows Collaborative

    Science.gov (United States)

    Foundry Foundry New Construction Windows Window Selection Tool Selection Process Design Guidance Installation Replacement Windows Window Selection Tool Assessing Options Selection Process Design Guidance Installation Understanding Windows Benefits Design Considerations Measuring Performance Performance Standards

  11. Windows forensic analysis toolkit advanced analysis techniques for Windows 7

    CERN Document Server

    Carvey, Harlan

    2012-01-01

    Now in its third edition, Harlan Carvey has updated "Windows Forensic Analysis Toolkit" to cover Windows 7 systems. The primary focus of this edition is on analyzing Windows 7 systems and on processes using free and open-source tools. The book covers live response, file analysis, malware detection, timeline, and much more. The author presents real-life experiences from the trenches, making the material realistic and showing the why behind the how. New to this edition, the companion and toolkit materials are now hosted online. This material consists of electronic printable checklists, cheat sheets, free custom tools, and walk-through demos. This edition complements "Windows Forensic Analysis Toolkit, 2nd Edition", (ISBN: 9781597494229), which focuses primarily on XP. It includes complete coverage and examples on Windows 7 systems. It contains Lessons from the Field, Case Studies, and War Stories. It features companion online material, including electronic printable checklists, cheat sheets, free custom tools, ...

  12. Advanced energy efficient windows

    DEFF Research Database (Denmark)

    Thomsen, Kirsten Engelund

    2007-01-01

    Windows should be paid special attention as they contribute a significant part of the total heat-loss coefficient of the building. Contrary to other parts of the thermal envelope the windows are not only heat loosers, but may gain heat in the day-time. Therefore there are possibilities for large...... energy savings. In terms of energy, windows occupy a special position compared with other thermal envelope structures due to their many functions: 1) windows let daylight into the building and provide occupants with visual contact with their surroundings 2) windows protect against the outdoor climate 3......) windows transmit solar energy that may contribute to a reduction of energy consumption, but which may also lead to unpleasant overheating. In the following paragraphs the current use of windows is reviewed with an emphasis on energy, while special products like solar protection glazing and security...

  13. Windows 8 secrets

    CERN Document Server

    Thurrott, Paul

    2012-01-01

    Tips, tricks, treats, and secrets revealed on Windows 8 Microsoft is introducing a major new release of its Windows operating system, Windows 8, and what better way to learn all its ins and outs than from two internationally recognized Windows experts and Microsoft insiders, authors Paul Thurrott and Rafael Rivera? They cut through the hype to get at useful information you'll not find anywhere else, including what role this new OS plays in a mobile and tablet world. Regardless of your level of knowledge, you'll discover little-known facts about how things work, what's new and different, and h

  14. Programming Windows Azure

    CERN Document Server

    Krishnan, Sriram

    2010-01-01

    Learn the nuts and bolts of cloud computing with Windows Azure, Microsoft's new Internet services platform. Written by a key member of the product development team, this book shows you how to build, deploy, host, and manage applications using Windows Azure's programming model and essential storage services. Chapters in Programming Windows Azure are organized to reflect the platform's buffet of services. The book's first half focuses on how to write and host application code on Windows Azure, while the second half explains all of the options you have for storing and accessing data on the plat

  15. Beginning Windows 8

    CERN Document Server

    Halsey, Mike

    2012-01-01

    Windows 8 has been described by Microsoft as its 'boldest' Windows release ever. Beginning Windows 8 takes you through the new features and helps you get more out of the familiar to reveal the possibilities for this amazing new operating system. You will learn, with non-technical language used throughout, how to get up and running in the new Windows interface, minimize downtime, maximize productivity, and harness the features you never knew existed to take control of your computer and enjoy the peace of mind and excitement that comes with it. From tips and tweaks to easy-to-follow guides and d

  16. Windows 8 tweaks

    CERN Document Server

    Sinchak, Steve

    2013-01-01

    Acres of Windows 8 tweaks from a Microsoft MVP and creator of Tweaks.com! From a Microsoft MVP, who is also the savvy creator of Tweaks.com, comes this ultimate collection of Windows 8 workarounds. Steve Sinchak takes you way beyond default system settings, deep under the hood of Windows 8, down to the hidden gems that let you customize your Windows 8 system like you wouldn't believe. From helping you customize the appearance to setting up home networking, sharing media, and squeezing every ounce of performance out of the OS, this book delivers. Get ready to rock and roll with Wind

  17. Electrical and Raman spectroscopic studies of vertically aligned multi-walled carbon nanotubes.

    Science.gov (United States)

    Mathur, Ashish; Tweedie, Mark; Roy, Susanta Sinha; Maguire, P D; McLaughlin, James A

    2009-07-01

    Microwave plasma enhanced chemical vapour deposition (MPECVD) was used for the production of carbon nanotubes. Vertically aligned multi-walled carbon nanotubes (MWCNTs) were grown on silicon substrates coated with cobalt thin films of thickness ranging from 0.5 nm to 3 nm. Prior to the nanotube growth the catalyst were treated with N2 plasma for 5-10 minutes that break the films into small nanoparticles which favour the growth of nanotubes. The CNTs were grown at a substrate temperature of 700 degrees C for 5, 10 and 15 minutes. The height of the CNT films ranging from 10 microm-30 microm indicating that the initial growth rate of the CNTs are very high at a rate of approximately 100 nm/sec. Electrical resistivity of the above samples was evaluated from I-V measurements. The activation energy (E(a)) was also calculated from the temperature dependent studies and it was found that the E(a) lies in the range of 15-35 meV. Raman spectroscopy was used to identify the quality of the nanotubes.

  18. Strain-dependent electrical resistance of multi-walled carbon nanotube/polymer composite films

    International Nuclear Information System (INIS)

    Park, Myounggu; Kim, Hyonny; Youngblood, Jeffrey P

    2008-01-01

    The strain-dependent electrical resistance characteristics of multi-walled carbon nanotube (MWCNT)/polymer composite films were investigated. In this research, polyethylene oxide (PEO) is used as the polymer matrix. Two representative volume fractions of MWCNT/PEO composite films were selected: 0.56 vol% (near the percolation threshold) and 1.44 vol% (away from the percolation threshold) of MWCNT. An experimental setup which can measure electrical resistance and strain simultaneously and continuously has been developed. Unique and repeatable relationships in resistance versus strain were obtained for multiple specimens with different volume fractions of MWCNT. The overall pattern of electrical resistance change versus strain for the specimens tested consists of linear and nonlinear regions. A resistance change model to describe the combination of linear and nonlinear modes of electrical resistance change as a function of strain is suggested. The unique characteristics in electrical resistance change for different volume fractions imply that MWCNT/PEO composite films can be used as tunable strain sensors and for application into embedded sensor systems in structures

  19. Fluorescence spectrometry of the interaction of multi-walled carbon nanotubes with catalase

    International Nuclear Information System (INIS)

    Fan, Y.; Cai, H.; Miao, J.; Yang, Q.; Li, Y.; Li, J.; Fu, D.

    2014-01-01

    The interaction of multi-walled carbon nanotubes (MWCNTs) with catalase is investigated using fluorescence and circular dichroism spectroscopic techniques. The results of the fluorescence experiments suggest that MWCNTs quench the intrinsic fluorescence of catalase via a static quenching mechanism. The circular dichroism spectral results reveal the unfolding of catalase with a significant decrease in the α-helix content in the presence of MWCNTs, which indicates that the conformation of catalase is changed in the binding process, thereby remarkably decreasing its activity. The binding constants and the number of binding sites of the MWCNT to the catalase are calculated at different temperatures. The thermodynamic parameters, such as the changes in free energy (ΔG), enthalpy (ΔH), and entropy (ΔS), are calculated using thermodynamic equations. The fact that all negative values of ΔG, ΔH, and ΔS are obtained suggests that the interaction of the MWCNTs with catalase is spontaneous, and that hydrogen bonding and van der Waals interactions play an important role in the binding process. (authors)

  20. Solar Energy Gain and Space-Heating Energy Supply Analyses for Solid-Wall Dwelling Retrofitted with the Experimentally Achievable U-value of Novel Triple Vacuum Glazing

    Directory of Open Access Journals (Sweden)

    Saim Memon

    2017-06-01

    Full Text Available A considerable effort is devoted to devising retrofit solutions for reducing space-heating energy in the domestic sector. Existing UK solid-wall dwellings, which have both heritage values and historic fabric, are being improved but they tend to have meagre thermal performance, partly, due to the heat-loss through glazings. This paper takes comparative analyses approach to envisage space-heating supply required in order to maintain thermal comfort temperatures and attainable solar energy gains to households with the retrofit of an experimentally achievable thermal performance of the fabricated sample of triple vacuum glazing to a UK solid-wall dwelling. 3D dynamic thermal models (timely regimes of heating, occupancy, ventilation and internal heat gains of an externally-insulated solid-wall detached dwelling with a range of existing glazing types along with triple vacuum glazings are modelled. A dramatic decrease of space-heating load and moderate increase of solar gains are resulted with the dwelling of newly achievable triple vacuum glazings (having centre-of-pane U-value of 0.33 Wm-2K-1 compared to conventional glazing types. The space-heating annual cost of single glazed dwellings was minimised to 15.31% (≈USD 90.7 with the retrofit of triple-vacuum glazings. An influence of total heat-loss through the fabric of solid-wall dwelling was analysed with steady-state calculations which indicates a fall of 10.23 % with triple vacuum glazings compared to single glazings.

  1. Cobalt hexacyanoferrate modified multi-walled carbon nanotubes/graphite composite electrode as electrochemical sensor on microfluidic chip

    Energy Technology Data Exchange (ETDEWEB)

    Li Xinchun [School of Pharmaceutical Sciences, Sun Yat-sen University, 132 Waihuan East Road of Higher Education Mega Centre, Guangzhou 510006 (China); Chen Zuanguang, E-mail: chenzg@mail.sysu.edu.cn [School of Pharmaceutical Sciences, Sun Yat-sen University, 132 Waihuan East Road of Higher Education Mega Centre, Guangzhou 510006 (China); Zhong Yuwen, E-mail: yu0106@163.com [Center for Disease Control and Prevention of Guangdong Province, 176 Xingangxi, Guangzhou 510300 (China); Yang Fan; Pan Jianbin; Liang Yajing [School of Pharmaceutical Sciences, Sun Yat-sen University, 132 Waihuan East Road of Higher Education Mega Centre, Guangzhou 510006 (China)

    2012-01-13

    Highlights: Black-Right-Pointing-Pointer CoHCF nanoparticles modified MWCNTs/graphite electrode use for electrochemistry on electrophoresis microchip for the first time. Black-Right-Pointing-Pointer Simultaneous, rapid, and sensitive electrochemical detection of hydrazine and isoniazid in real samples. Black-Right-Pointing-Pointer An exemplary work of CME sensor assembly onto microchip for determination of analytes with environmental significance. Black-Right-Pointing-Pointer Manifestation of the applicability and flexibility of CME sensor for electroanalysis on microfluidic chip. - Abstract: Nanomaterial-based electrochemical sensor has received significant interest. In this work, cobalt hexacyanoferrate modified multi-walled carbon nanotubes/graphite composite electrode was electrochemically prepared and exploited as an amperometric detector for microchip electrophoresis. The prepared sensor displayed rapid and sensitive response towards hydrazine and isoniazid oxidation, which was attributed to synergetic electrocatalytic effect of cobalt hexacyanoferrate and multi-walled carbon nanotubes. The sensitivity enhancement with nearly two orders of magnitude was gained, compared with the bare carbon paste electrode, with the detection limit of 0.91 {mu}M (S/N = 3) for hydrazine. Acceptable repeatability of the microanalysis system was verified by consecutive eleven injections of hydrazine without chip and electrode treatments, the RSDs for peak current and migration time were 3.4% and 2.1%, respectively. Meanwhile, well-shaped electrophoretic peaks were observed, mainly due to fast electron transfer of electroactive species on the modified electrode. The developed microchip-electrochemistry setup was successfully applied to the determination of hydrazine and isoniazid in river water and pharmaceutical preparation, respectively. Several merits of the novel electrochemical sensor coupled with microfluidic platform, such as comparative stability, easy fabrication and

  2. Improvements on digital inline holographic PTV for 3D wall-bounded turbulent flow measurements

    International Nuclear Information System (INIS)

    Toloui, Mostafa; Mallery, Kevin; Hong, Jiarong

    2017-01-01

    Three-dimensional (3D) particle image velocimetry (PIV) and particle tracking velocimetry (PTV) provide the most comprehensive flow information for unraveling the physical phenomena in a wide range of fluid problems, from microfluidics to wall-bounded turbulent flows. Compared with other 3D PIV techniques, such as tomographic PIV and defocusing PIV, the digital inline holographic PTV (DIH-PTV) provides 3D flow measurement solution with high spatial resolution, low cost optical setup, and easy alignment and calibration. Despite these advantages, DIH-PTV suffers from major limitations including poor longitudinal resolution, human intervention (i.e. requirement for manually determined tuning parameters during tracer field reconstruction and extraction), limited tracer concentration, small sampling volume and expensive computations, limiting its broad use for 3D flow measurements. In this study, we present our latest developments on minimizing these challenges, which enables high-fidelity DIH-PTV implementation to larger sampling volumes with significantly higher particle seeding densities suitable for wall-bounded turbulent flow measurements. The improvements include: (1) adjustable window thresholding; (2) multi-pass 3D tracking; (3) automatic wall localization; and (4) continuity-based out-of-plane velocity component computation. The accuracy of the proposed DIH-PTV method is validated with conventional 2D PIV and double-view holographic PTV measurements in smooth-wall turbulent channel flow experiments. The capability of the technique in characterization of wall-bounded turbulence is further demonstrated through its application to flow measurements for smooth- and rough-wall turbulent channel flows. In these experiments, 3D velocity fields are measured within sampling volumes of 14.7  ×  50.0  ×  14.4 mm 3 (covering the entire depth of the channel) with a velocity resolution of  <1.1 mm/vector. Overall, the presented DIH-PTV method and

  3. Electrochemical biosensing of galactose based on carbon materials: graphene versus multi-walled carbon nanotubes.

    Science.gov (United States)

    Dalkıran, Berna; Erden, Pınar Esra; Kılıç, Esma

    2016-06-01

    In this study, two enzyme electrodes based on graphene (GR), Co3O4 nanoparticles and chitosan (CS) or multi-walled carbon nanotubes (MWCNTs), Co3O4 nanoparticles, and CS, were fabricated as novel biosensing platforms for galactose determination, and their performances were compared. Galactose oxidase (GaOx) was immobilized onto the electrode surfaces by crosslinking with glutaraldehyde. Optimum working conditions of the biosensors were investigated and the analytical performance of the biosensors was compared with respect to detection limit, linearity, repeatability, and stability. The MWCNTs-based galactose biosensor provided about 1.6-fold higher sensitivity than its graphene counterpart. Moreover, the linear working range and detection limit of the MWCNTs-based galactose biosensor was superior to the graphene-modified biosensor. The successful application of the purposed biosensors for galactose biosensing in human serum samples was also investigated.

  4. Chest Wall tumor: combined management

    International Nuclear Information System (INIS)

    Rao Bhaskar, N.

    1997-01-01

    Cancer is relatively rare disease among children and adolescents. The incidence of solid tumors other than CNS is less than 2/100,000. Tumors of the chest wall can arise either from the somatic tissue or ribs. These are rare, so either institutional reviews or multi institutional studies should determine optimal therapeutic management. Of the bony chest wall, Ewing's sarcoma or the family of tumor (peripheral neuro epithelioma, Askin tumor), are the most common. These lesions are lytic and have associated large extra pleural component. This large extra pleural component often necessitates major chest wall resection (3 or more ribs), and when lower ribs are involved, this entails resection of portion of diaphragm. Despite this resection, survival in the early 1970 was 10-20%. Since 1970 multi agent chemotherapy has increased survival rates. of importance, however, is these regimens have caused significant reduction of these extra pleural components so that major chest wall resections have become a rarity. With improved survival and decreased morbidity preoperative chemotherapy followed by surgery is now the accepted modality of treatment. Another major advantage of this regimen is that potential radiation therapy may be obviated. The most common chest wall lesion is rhabdomyosarcoma. In the IRS study of 1620 RMS patients, in 141 (9%) the primary lesion was in the chest wall. these are primarily alveolar histology. when lesions were superficial, wide local excision with supplemental radiation therapy was associated with low morbidity and good overall survival. however, a majority have significant intra- thoracic components. in these circumstances the resectability rate is less than 30% and the survival poor. Other lesions include non rhabdomyosarcomas, eosinophilic granuloma, chondrosarcoma, and osteomyelitis. The management of these lesions varies according to extent, histology, and patient characteristics

  5. Effect of chemical treatments on hydrogen storage behaviors of multi-walled carbon nanotubes

    International Nuclear Information System (INIS)

    Lee, Seul-Yi; Park, Soo-Jin

    2010-01-01

    In this work, the hydrogen storage behaviors of chemically treated multi-walled carbon nanotubes (MWNTs) were investigated. The surface properties of the functionalized MWNTs were confirmed by Fourier transfer infrared spectroscopy, X-ray diffraction, the Boehm titration method, and zeta-potential measurements. The hydrogen storage capacity of the MWNTs was evaluated at 298 K and 100 bar. In the experimental results, it was found that the chemical treatments introduced functional groups onto the MWNT surfaces. The amount of hydrogen storage was enhanced, by acidic surface treatment, to 0.42 wt.% in the acidic-treated MWNTs compared with 0.26 wt.% in the as-received MWNTs. Meanwhile, the basic surface treatment actually reduced the hydrogen storage capacity, to 0.24 wt.% in the basic-treated MWNTs sample. Consequently, it could be concluded that hydrogen storage is greatly influenced by the acidic characteristics of MWNT surfaces, resulting in enhanced electron acceptor-donor interaction at interfaces.

  6. Gas sensors for ammonia detection based on polyaniline-coated multi-wall carbon nanotubes

    International Nuclear Information System (INIS)

    He Lifang; Jia Yong; Meng Fanli; Li Minqiang; Liu Jinhuai

    2009-01-01

    Polyaniline-coated multi-wall carbon nanotubes (PANI-coated MWNTs) were prepared by in situ polymerization method. Field emission scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, and thermogravimetric analysis were used to characterize the as-prepared PANI-coated MWNTs. Obtained results indicated that PANI was uniformly coated on MWNTs, and the thickness of the coatings can be controlled by changing the weight ratios of aniline monomer and MWNTs in the polymerization process. Sensors were fabricated by spin-coating onto pre-patterned electrodes, and ammonia gas sensing properties of the as-prepared PANI-coated MWNTs were studied. The results showed a good response and reproducibility towards ammonia at room temperature. In addition, PANI-coated MWNTs exhibited a linear response to ammonia in the range of 0.2-15 ppm. The effects of the thickness of PANI coatings on the gas sensing properties were also investigated in detail. The results suggest a potential application of PANI-coated MWNTs in gas sensor for detecting ammonia.

  7. Electrical resistivity and thermal properties of compatibilized multi-walled carbon nanotube/polypropylene composites

    Directory of Open Access Journals (Sweden)

    A. Szentes

    2012-06-01

    Full Text Available The electrical resistivity and thermal properties of multi-walled carbon nanotube/polypropylene (MWCNT/PP composites have been investigated in the presence of coupling agents applied for improving the compatibility between the nanotubes and the polymer. A novel olefin-maleic-anhydride copolymer and an olefin-maleic-anhydride copolymer based derivative have been used as compatibilizers to achieve better dispersion of MWCNTs in the polymer matrix. The composites have been produced by extrusion followed by injection moulding. They contained different amounts of MWCNTs (0.5, 2, 3 and 5 wt% and coupling agent to enhance the interactions between the carbon nanotubes and the polymer. The electrical resistivity of the composites has been investigated by impedance spectroscopy, whereas their thermal properties have been determined using a thermal analyzer operating on the basis of the periodic thermal perturbation method. Rheological properties, BET-area and adsorption-desorption isotherms have been determined. Dispersion of MWCNTs in the polymer has been studied by scanning electron microscopy (SEM.

  8. Rheological and mechanical properties of polypropylene prepared with multi-walled carbon nanotube masterbatch.

    Science.gov (United States)

    Shim, Young-Sun; Park, Soo-Jin

    2012-07-01

    In this study, the effects of polypropylene-grafted maleic-anhydride-treated multi-walled carbon nanotubes (PP-MWNTs) on the viscoelastic behaviors and mechanical properties of a polypropylene-(PP)-based composite system were examined. The PP-MWNT/PP composites were prepared via melt mixing with a 3:1 ratio of PP-g-MA and acid-treated MWNTs at 220 degrees C. The surface characteristics of the PP-MWNTs were confirmed via Fourier transform infrared (FTIR) spectroscopy and transmission electron microscopy (TEM). The viscoelastic behavior and mechanical properties of the PP-MWNT/PP composites were confirmed using a rheometer and an ultimate testing machine (UTM). The storage and loss moduli increased with increasing PP-MWNT content. The critical intensity stress factor (K(IC)) of the PP-MWNT/PP composites at high filler loading was also higher than that of the MWNT/PP composites. In conclusion, the viscoelastic behavior and mechanical properties of MWNT/PP can be improved by grafting MWNTs to PP-g-MA.

  9. Bilirubin oxidase bound to multi-walled carbon nanotube-modified gold

    International Nuclear Information System (INIS)

    Schubert, Kirsten; Goebel, Gero; Lisdat, Fred

    2009-01-01

    We report on direct electron transfer (DET) reactions of bilirubin oxidase at multi-walled carbon nanotube-(MWCNT) modified gold electrodes. MWCNTs are very suitable for protein immobilisation and provide surface groups that can be used for the stable fixation on electrodes. They can also effectively replace the natural substrate of BOD - bilirubin, the electron donor for oxygen reduction. The bioelectrocatalytic oxygen reduction was recorded using linear sweep voltammetry (LSV) with BOD covalently linked to the nanotubes. The start potential of the bioelectrocatalytic oxygen reduction at pH 7 and a scan rate of 10 mV/s was determined to be 485 ± 10 mV vs. Ag/AgCl, 1 M KCl (720 mV vs. SHE). Current densities up to 500 μA/cm 2 were detected in an air-saturated buffer at room temperature (25 ± 5 deg. C). Experiments with a rotating disk electrode (RDE) indicate a diffusion controlled electrode reaction. A k s value in the range of 80-100 s -1 could be estimated. The DET could also be observed directly by the redox conversion of a copper centre of BOD under anaerobic conditions. A peak pair with a formal potential of 680 ± 10 mV vs. SHE was found. The T1 site is probably addressed by the electrode as indicated by several experimental studies

  10. Image-preprocessing method for near-wall particle image velocimetry (PIV) image interrogation with very large in-plane displacement

    International Nuclear Information System (INIS)

    Zhu, Yiding; Yuan, Huijing; Zhang, Chuanhong; Lee, Cunbiao

    2013-01-01

    Accurate particle image velocimetry (PIV) measurements very near the wall are still a great challenge. The problem is compounded by the very large in-plane displacement on PIV images commonly encountered in measurements in hypersonic boundary layers. An improved image-preprocessing method is presented in this paper which expands the traditional window deformation iterative multigrid scheme to PIV images with very large displacement. Before the interrogation, stationary artificial particles of uniform size are added homogeneously in the wall region. The mean squares of the intensities of signals in the flow and in the wall region are postulated to be equal when half the initial interrogation window overlaps the wall region. The initial estimation near the wall is then smoothed by data from both sides of the shear layer to reduce the large random uncertainties. Interrogations in the following iterative steps then converge to the correct results to provide accurate predictions for particle tracking velocimetries. Significant improvement is seen in Monte Carlo simulations and experimental tests. The algorithm successfully extracted the small flow structures of the second-mode wave in the hypersonic boundary layer from PIV images with low signal-noise-ratios when the traditional method was not successful. (paper)

  11. A Pilot Demonstration of Electrochromic and Thermochromic Windows in the Denver Federal Center, Building 41, Denver, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eleanor S. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Fernandes, Luis L. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Goudey, Chad Howdy [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Jonsson, Carl Jacob [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Curcija, D. Charlie [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Pang, Xiufeng [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); DiBartolomeo, Dennis [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hoffmann, Sabine [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2013-07-01

    Chromogenic glazing materials are emerging technologies that tint reversibly from a clear to dark tinted state either passively in response to environmental conditions or actively in response to a command from a switch or building automation system. Switchable coatings on glass manage solar radiation and visible light while enabling unobstructed views to the outdoors. Building energy simulations estimate that actively controlled, near-term chromogenic glazings can reduce perimeter zone heating, ventilation, and airconditioning (HVAC) and lighting energy use by 10-20% and reduce peak electricity demand by 20-30%, achieving energy use levels that are lower than an opaque, insulated wall. This project demonstrates the use of two types of chromogenic windows: thermochromic and electrochromic windows. By 2013, these windows will begin production in the U.S. by multiple vendors at high-volume manufacturing plants, enabling lower cost and larger area window products to be specified. Both technologies are in the late R&D stage of development, where cost reductions and performance improvements are underway. Electrochromic windows have been installed in numerous buildings over the past four years, but monitored energy-efficiency performance has been independently evaluated in very limited applications. Thermochromic windows have been installed in one other building with an independent evaluation, but results have not yet been made public.

  12. Solvent-free functionalization of fullerene C{sub 60} and pristine multi-walled carbon nanotubes with aromatic amines

    Energy Technology Data Exchange (ETDEWEB)

    Ramírez-Calera, Itzel J. [Centro de Ciencias Aplicadas y Desarrollo Tecnológico, Universidad Nacional Autónoma de México, Circuito Exterior C. U., 04510, México, D.F. (Mexico); Meza-Laguna, Victor [Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Circuito Exterior C. U., 04510 México, D.F. (Mexico); Gromovoy, Taras Yu. [O.O. Chuiko Institute of Surface Chemistry, National Academy of Sciences of the Ukraine, Gen. Naumova 17, 03164 Kiev (Ukraine); Chávez-Uribe, Ma. Isabel [Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior C. U., 04510 México, D.F. (Mexico); Basiuk, Vladimir A., E-mail: basiuk@nucleares.unam.mx [Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Circuito Exterior C. U., 04510 México, D.F. (Mexico); Basiuk, Elena V., E-mail: elbg1111@gmail.com [Centro de Ciencias Aplicadas y Desarrollo Tecnológico, Universidad Nacional Autónoma de México, Circuito Exterior C. U., 04510, México, D.F. (Mexico)

    2015-02-15

    Highlights: • Pristine multi-walled carbon nanotubes were functionalized with aromatic amines. • The amines add onto nanotube defects, likewise they add onto fullerene C{sub 60}. • The addition takes place at elevated temperature and without organic solvents. • Functionalized nanotubes were characterized by a number of instrumental techniques. - Abstract: We employed a direct one-step solvent-free covalent functionalization of solid fullerene C{sub 60} and pristine multi-walled carbon nanotubes (MWCNTs) with aromatic amines 1-aminopyrene (AP), 2-aminofluorene (AF) and 1,5-diaminonaphthalene (DAN). The reactions were carried out under moderate vacuum, in a wide temperature range of 180–250 °C, during relatively short time of about 2 h. To confirm successful amine attachment, a large number of analytical techniques were used (depending on the nanomaterial functionalized) such as Fourier transform infrared, Raman, X-ray photoelectron, {sup 13}C cross-polarization magic angle spinning NMR spectroscopy, thermogravimetric analysis, laser-desorption ionization time-of-flight mass spectrometry, temperature-programmed desorption with mass spectrometric detection, as well as scanning and transmission electron microscopy. The nucleophilic addition of the aromatic amines to C{sub 60} molecule was studied theoretically by using density functional theory (PBE GGA functional with Grimme dispersion correction in conjunction with the DNP basis set). In the case of crystalline C{sub 60}, the solvent-free technique has a limited applicability due to poor diffusion of vaporous aromatic amines into the bulk. Nevertheless, the approach proposed allows for a facile preparation of aromatic amine-functionalized pristine MWCNTs without contamination with other chemical reagents, detergents and solvents, which is especially important for a vast variety of nanotube applications spanning from nanoelectronics to nanomedicine.

  13. Window selection for dual photopeak window scatter correction in Tc-99m imaging

    International Nuclear Information System (INIS)

    Vries, D.J. de; King, M.A.

    1994-01-01

    The width and placement of the windows for the dual photopeak window (DPW) scatter subtraction method for Tc-99m imaging is investigated in order to obtain a method that is stable on a multihead detector system for single photon emission computed tomography (SPECT) and is capable of providing a good scatter estimate for extended objects. For various window pairs, stability and noise were examined with experiments using a SPECT system, while Monte Carlo simulations were used to predict the accuracy of scatter estimates for a variety of objects and to guide the development of regression relations for various window pairs. The DPW method that resulted from this study was implemented with a symmetric 20% photopeak window composed of a 15% asymmetric photopeak window and a 5% lower window abutted at 7 keV below the peak. A power function regression was used to relate the scatter-to-total ratio to the lower window-to-total ratio at each pixel, from which an estimated scatter image was calculated. DPW demonstrated good stability, achieved by abutting the two windows away from the peak. Performance was assessed and compared with Compton window subtraction (CWS). For simulated extended objects, DPW generally produced a less biased scatter estimate than the commonly used CWS method with k = 0.5. In acquisitions of a clinical SPECT phantom, contrast recovery was comparable for both DPW and CWS; however, DPW showed greater visual contrast in clinical SPECT bone studies

  14. Investigation of Retrofit Solutions of Window-Wall Assembly Based on FMEA, Energy Performance and Indoor Environment

    DEFF Research Database (Denmark)

    Morelli, Martin; Lauritsen, Diana; Svendsen, Svend

    2011-01-01

    to moisture from the inside. The box window has the lowest temperatures on the cavity surface and is therefore more vulnerable toward condensation. The basis of the rational optimisation approach is the total economy considering the initial, operational and maintenance costs over the lifetime of the building...

  15. The hepatotoxicity of multi-walled carbon nanotubes in mice

    Science.gov (United States)

    Ji, Zongfei; Zhang, Danying; Li, Ling; Shen, Xizhong; Deng, Xiaoyong; Dong, Ling; Wu, Minhong; Liu, Yuanfang

    2009-11-01

    The hepatotoxicity of two types of multi-walled carbon nanotubes (MWCNTs), acid-oxidized MWCNTs (O-MWCNTs) and Tween-80-dispersed MWCNTs (T-MWCNTs), were investigated with Kunming mice exposed to 10 and 60 mg kg-1 by intravenous injection for 15 and 60 d. Compared with the PBS group, the body-weight gain of the mice decreased and the level of total bilirubin and aspartate aminotransferase increased in the MWCNT-exposed group with a significant dose-effect relationship, while tumor necrosis factor alpha level did not show significant statistical change within 60 d. Spotty necrosis, inflammatory cell infiltration in portal region, hepatocyte mitochondria swelling and lysis were observed with a significant dose-effect relationship in the MWCNT groups. Liver damage of the T-MWCNT group was more severe than that of the O-MWCNT group according to the Roenigk classification system. Furthermore, T-MWCNTs induce slight liver oxidative damage in mice at 15 d, which was recovered at 60 d. Part of the gene expressions of mouse liver in the MWCNT groups changed compared to the PBS group, including GPCRs (G protein-coupled receptors), cholesterol biosynthesis, metabolism by cytochrome P450, natural-killer-cell-mediated cytotoxicity, TNF- α, NF-κB signaling pathway, etc. In the P450 pathway, the gene expressions of Gsta2 (down-regulated), Cyp2B19 (up-regulated) and Cyp2C50 (down-regulated) had significant changes in the MWCNT groups. These results show that a high dose of T-MWCNTs can induce hepatic toxicity in mice while O-MWCNTs seem to have less toxicity.

  16. A facile approach to the synthesis of hydrophobic iron tetrasulfophthalocyanine (FeTSPc) nano-aggregates on multi-walled carbon nanotubes: A potential electrocatalyst for the detection of dopamine

    CSIR Research Space (South Africa)

    Fashedemi, OO

    2011-07-01

    Full Text Available A facile method has been utilized to synthesize ahydrophobic form of nano-scaled iron (II) tetrasulfophthalocyanine (nanoFeTSPc), integrated with functionalized multi-walled carbon nanotubes (fMWCNT-nanoFeTSPc). The nanocomposite was characterized...

  17. In vivo translocation and toxicity of multi-walled carbon nanotubes are regulated by microRNAs

    Science.gov (United States)

    Zhao, Yunli; Wu, Qiuli; Li, Yiping; Nouara, Abdelli; Jia, Ruhan; Wang, Dayong

    2014-03-01

    We employed an in vivo Caenorhabditis elegans assay system to perform SOLiD sequencing analysis to identify the possible microRNA (miRNA) targets of multi-walled carbon nanotubes (MWCNTs). Bioinformatics analysis on targeted genes for the identified dysregulated miRNAs in MWCNT exposed nematodes demonstrates their involvement in many aspects of biological processes. We used loss-of-function mutants for the identified dysregulated miRNAs to perform toxicity assessment by evaluating functions of primary and secondary targeted organs, and found the miRNA mutants with susceptible or resistant property towards MWCNT toxicity. Both the physiological state of the intestine and defecation behavior were involved in the control of the susceptible or resistant property occurrence for specific miRNA mutants towards MWCNT toxicity. This work provides the molecular basis at the miRNA level for future chemical design to reduce the nanotoxicity of MWCNTs and further elucidation of the related toxicological mechanism.We employed an in vivo Caenorhabditis elegans assay system to perform SOLiD sequencing analysis to identify the possible microRNA (miRNA) targets of multi-walled carbon nanotubes (MWCNTs). Bioinformatics analysis on targeted genes for the identified dysregulated miRNAs in MWCNT exposed nematodes demonstrates their involvement in many aspects of biological processes. We used loss-of-function mutants for the identified dysregulated miRNAs to perform toxicity assessment by evaluating functions of primary and secondary targeted organs, and found the miRNA mutants with susceptible or resistant property towards MWCNT toxicity. Both the physiological state of the intestine and defecation behavior were involved in the control of the susceptible or resistant property occurrence for specific miRNA mutants towards MWCNT toxicity. This work provides the molecular basis at the miRNA level for future chemical design to reduce the nanotoxicity of MWCNTs and further elucidation of the

  18. Multi-walled carbon nanotube-induced gene expression in the mouse lung: Association with lung pathology

    International Nuclear Information System (INIS)

    Pacurari, M.; Qian, Y.; Porter, D.W.; Wolfarth, M.; Wan, Y.; Luo, D.; Ding, M.; Castranova, V.; Guo, N.L.

    2011-01-01

    Due to the fibrous shape and durability of multi-walled carbon nanotubes (MWCNT), concerns regarding their potential for producing environmental and human health risks, including carcinogenesis, have been raised. This study sought to investigate how previously identified lung cancer prognostic biomarkers and the related cancer signaling pathways are affected in the mouse lung following pharyngeal aspiration of well-dispersed MWCNT. A total of 63 identified lung cancer prognostic biomarker genes and major signaling biomarker genes were analyzed in mouse lungs (n = 80) exposed to 0, 10, 20, 40, or 80 μg of MWCNT by pharyngeal aspiration at 7 and 56 days post-exposure using quantitative PCR assays. At 7 and 56 days post-exposure, a set of 7 genes and a set of 11 genes, respectively, showed differential expression in the lungs of mice exposed to MWCNT vs. the control group. Additionally, these significant genes could separate the control group from the treated group over the time series in a hierarchical gene clustering analysis. Furthermore, 4 genes from these two sets of significant genes, coiled-coil domain containing-99 (Ccdc99), muscle segment homeobox gene-2 (Msx2), nitric oxide synthase-2 (Nos2), and wingless-type inhibitory factor-1 (Wif1), showed significant mRNA expression perturbations at both time points. It was also found that the expression changes of these 4 overlapping genes at 7 days post-exposure were attenuated at 56 days post-exposure. Ingenuity Pathway Analysis (IPA) found that several carcinogenic-related signaling pathways and carcinogenesis itself were associated with both the 7 and 11 gene signatures. Taken together, this study identifies that MWCNT exposure affects a subset of lung cancer biomarkers in mouse lungs. - Research highlights: → Multi-Walled Carbon Nanotubes affect lung cancer biomarkers in mouse lungs. → The results suggest potentially harmful effects of MWCNT exposure on human lungs. → The results could potentially be used

  19. Purification of Zinc Bromide Solution used as shield in hot cells windows for handling of highly radioactive sources

    International Nuclear Information System (INIS)

    Acosta-Leon, C.E.

    1989-10-01

    After some time of use zinc bromide solutions get a yellowish colour and form brownish precipitate, sticking on the walls of the windows that seem to be dirty caused by the effect of the solution penetrating into the packing and epoxy layer of the windows; all these effects cause the corrosive attack over the metallic parts of the window's frame and the same time the clarity and visibility inside the windows become defective. The aim and purpose of the present work was to set up a method intended for the recovery of all the solutions avoiding the use of a new one, the deviation of the original properties was corrected, and the recovered solutions could be used immediately; the experiments were done in the laboratory using a pyrex glass vacuum evaporator flash type, and the results were successful. The sample volume was 1500 1, and the time employed to 100 days. (Author)

  20. Kinetic and isotherm modeling of Cd (II) adsorption by L-cysteine functionalized multi-walled carbon nanotubes as adsorbent.

    Science.gov (United States)

    Taghavi, Mahmoud; Zazouli, Mohammad Ali; Yousefi, Zabihollah; Akbari-adergani, Behrouz

    2015-11-01

    In this study, multi-walled carbon nanotubes were functionalized by L-cysteine to show the kinetic and isotherm modeling of Cd (II) ions onto L-cysteine functionalized multi-walled carbon nanotubes. The adsorption behavior of Cd (II) ion was studied by varying parameters including dose of L-MWCNTs, contact time, and cadmium concentration. Equilibrium adsorption isotherms and kinetics were also investigated based on Cd (II) adsorption tests. The results showed that an increase in contact time and adsorbent dosage resulted in increase of the adsorption rate. The optimum condition of the Cd (II) removal process was found at pH=7.0, 15 mg/L L-MWCNTs dosage, 6 mg/L cadmium concentration, and contact time of 60 min. The removal percent was equal to 89.56 at optimum condition. Langmuir and Freundlich models were employed to analyze the experimental data. The data showed well fitting with the Langmuir model (R2=0.994) with q max of 43.47 mg/g. Analyzing the kinetic data by the pseudo-first-order and pseudo-second-order equations revealed that the adsorption of cadmium using L-MWSNTs following the pseudo-second-order kinetic model with correlation coefficients (R2) equals to 0.998, 0.992, and 0.998 for 3, 6, and 9 mg/L Cd (II) concentrations, respectively. The experimental data fitted very well with the pseudo-second-order. Overall, treatment of polluted solution to Cd (II) by adsorption process using L-MWCNT can be considered as an effective technology.

  1. Relation between the Fluctuating Wall Pressure and the Turbulent Structure of a Boundary Layer on a Cylinder in Axial Flow

    Science.gov (United States)

    1993-08-12

    Rlain in . power spectral density of the fluctuating wall pressure on the cylinder, boldine . fractional contribution to the total wall pressure energy...or repeated sequences of events are responsible for the production of turbulence in the near- wall region and the desire to extract their...signals over a prespecified window centered about the event detection times to extract the individual events. I 3.) Ensemble average the individual

  2. Systemic and immunotoxicity of pristine and PEGylated multi-walled carbon nanotubes in an intravenous 28 days repeated dose toxicity study.

    Science.gov (United States)

    Zhang, Ting; Tang, Meng; Zhang, Shanshan; Hu, Yuanyuan; Li, Han; Zhang, Tao; Xue, Yuying; Pu, Yuepu

    2017-01-01

    The numerous increasing use of carbon nanotubes (CNTs) derived from nanotechnology has raised concerns about their biosafety and potential toxicity. CNTs cause immunologic dysfunction and limit the application of CNTs in biomedicine. The immunological responses induced by pristine multi-walled carbon nanotubes (p-MWCNTs) and PEGylated multi-walled carbon nanotubes (MWCNTs-PEG) on BALB/c mice via an intravenous administration were investigated. The results reflect that the p-MWCNTs induced significant increases in spleen, thymus, and lung weight. Mice treated with p-MWCNTs showed altered lymphocyte populations (CD3 + , CD4 + , CD8 + , and CD19 + ) in peripheral blood and increased serum IgM and IgG levels, and splenic macrophage ultrastructure indicated mitochondria swelling. p-MWCNTs inhibited humoral and cellular immunity function and were associated with decreased immune responses against sheep erythrocytes and serum hemolysis level. Natural killer (NK) activity was not modified by two types of MWCNTs. In comparison with two types of MWCNTs, for a same dose, p-MWCNTs caused higher levels of inflammation and immunosuppression than MWCNTs-PEG. The results of immunological function suggested that after intravenous administration with p-MWCNTs caused more damage to systemic immunity than MWCNTs-PEG. Here, we demonstrated that a surface functional modification on MWCNTs reduces their immune perturbations in vivo. The chemistry-modified MWCNTs change their preferred immune response in vivo and reduce the immunotoxicity of p-MWCNTs.

  3. A Multi Mega Watt Continuous Wave RF Window for Particle Accelerator Applications. Final Technical Report

    International Nuclear Information System (INIS)

    Vguyen-Tuong, V.

    2004-01-01

    In this analysis the proposed 10MW window design is free of multipacting on the ceramic surface for the full power range, both in the traveling wave and full reflection mode. Near 7MW and 8MW in the traveling wave mode, multipacting might show up on the outer conductor of the matching section. These multipacting barriers are however very soft and are expected to be easily eliminated by regular RF processing. The multipacting analysis can identify early design problems while it is unable to provide certainty in design success and testing of window designs is the only certain measure of freedom from multipacting

  4. Improved L-cysteine electrocatalysis through a sequential drop dry technique using multi-walled carbon nanotubes and cobalt tetraaminophthalocyanine conjugates

    International Nuclear Information System (INIS)

    Nyoni, Stephen; Mugadza, Tawanda; Nyokong, Tebello

    2014-01-01

    Graphical abstract: A sequential drop dry modification of a glassy carbon electrode where by multiwalled carbon nanotubes are first placed on to the electrode followed by cobalt tetraaminophthalocyanine gave a better catalytic response towards the oxidation of L-cysteine than when the two components were mixed, due to the higher catalytic activity of the former as judged by scanning electrochemical microscopy. - Highlights: • A glassy carbon electrode modified with multi-walled carbon nanotubes and cobalt tetraaminophthalocyanine by a sequential drop dry method. • The modified surface gave a better catalytic response towards the oxidation of L-cysteine than when the individual components were mixed. • Scanning electrochemical microscopy was employed for surface characterization. - Abstract: Voltammetry, chronoamperometry, scanning electrochemical microscopy and electrochemical impedance spectroscopy methods are used for characterization of a glassy carbon electrode modified with multi-walled carbon nanotubes (MWCNTs)–cobalt tetraaminophthalocyanine (CoTAPc) mixture or sequential drop dry modification technique whereby the MWCNTs are first placed on to the electrode followed by CoTAPc. The sequential drop dry CoTAPc–MWCNTs modified surface gave better catalytic responses with a catalytic rate constant of 2.2 × 10 5 M −1 s −1 , apparent electron transfer rate constant of 0.073 cm s −1 , and a limit of detection of 2.8 × 10 −7 M. Scanning electrochemical microscopy (SECM) surface characterization (topography and reactivity) further gave proof the better catalytic perfomance of the sequential drop dry CoTAPc–MWCNTs modified surface

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

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Chunwei; Hu, Xinguo; Wang, Dianlong; Dai, Changsong [Department of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (China); Zhang, Liang; Jin, Haibo [School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081 (China); Agathopoulos, Simeon [Department of Materials Science and Engineering, University of Ioannina, GR-451 10 Ioannina (Greece)

    2006-09-29

    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 0.5M 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. (author)

  6. A Novel of Multi-wall Carbon Nanotubes/Chitosan Electrochemical Sensor for Determination of Cupric ion

    Science.gov (United States)

    Tan, Funeng; Li, Lei

    2018-03-01

    A multi-wall carbon nanotubes/Chitosan electrochemical sensor had been fabricated by dropping CHS/MWNT solution directly onto the GC surface. The sensor was charactered by cyclic voltammetry and AC impedance with K3Fe(CN)6 as a electrochemical probe; Cyclic voltammograms(CV) and electrochemical impedance spectroscopy(EIS) indicated that the active area and electrochemical behavior of the sensor increased and improved significantly after the electrode was modified by carbon nanotubes dispersed by the chitosan. The sensor showed good electrocatalytic activity of K3Fe(CN)6. Also, from the cyclic voltammograms, we can see the process was diffusion controlled on the bare electrode and kinetics and diffusion controlled on the modified electrode. Finally Cu2+ responsed sensitively at the sensor which supplied a new method for the detection of Cu2+.

  7. Anchoring alpha-manganese oxide nanocrystallites on multi-walled carbon nanotubes as electrode materials for supercapacitor

    Science.gov (United States)

    Li, Li; Qin, Zong-Yi; Wang, Ling-Feng; Liu, Hong-Jin; Zhu, Mei-Fang

    2010-09-01

    The partial coverage of manganese oxide (MnO2) particles was achieved on the surfaces of multi-walled carbon nanotubes (MWCNTs) through a facile hydrothermal process. These particles were demonstrated to be alpha-manganese dioxide (α-MnO2) nanocrystallites, and exhibited the appearance of the whisker-shaped crystals with the length of 80-100 nm. In such a configuration, the uncovered CNTs in the nanocomposite acted as a good conductive pathway and the whisker-shaped MnO2 nanocrystallites efficiently increased the contact of the electrolyte with the active materials. Thus, the highest specific capacitance of 550 F g-1 was achieved using the resulting nanocomposites as the supercapacitor electrode. In addition, the enhancement of the capacity retention was observed, with the nanocomposite losing only 10% of the maximum capacity after 1,500 cycles.

  8. Efecto del uso de diferentes aditivos de panificación en la calidad de panes elaborados con harinas compuestas a base de harina de trigo y germen desgrasado de maíz

    OpenAIRE

    Granito,Marisela; Guerra,Marisa

    1997-01-01

    Dado el alto consumo de productos alimenticios a base de trigo (HT) importado y la producción industrial de subproductos del procesamiento del maíz (HGDM), ricos en fibra dietética, proteínas y minerales, en Venezuela se ha estudado la factibilidad técnica de sustituir parcialmente HT por HGDM en la elaboración de productos horneados como galletas y panes. Por otra parte, considerando las restricciones existentes en el uso del bromato de potasio (BP) como aditivo de panificación y que el ácid...

  9. Windows for Intel Macs

    CERN Document Server

    Ogasawara, Todd

    2008-01-01

    Even the most devoted Mac OS X user may need to use Windows XP, or may just be curious about XP and its applications. This Short Cut is a concise guide for OS X users who need to quickly get comfortable and become productive with Windows XP basics on their Macs. It covers: Security Networking ApplicationsMac users can easily install and use Windows thanks to Boot Camp and Parallels Desktop for Mac. Boot Camp lets an Intel-based Mac install and boot Windows XP on its own hard drive partition. Parallels Desktop for Mac uses virtualization technology to run Windows XP (or other operating systems

  10. Monocyte adhesion induced by multi-walled carbon nanotubes and palmitic acid in endothelial cells and alveolar-endothelial co-cultures

    DEFF Research Database (Denmark)

    Cao, Yi; Roursgaard, Martin; Jacobsen, Nicklas Raun

    2016-01-01

    Free palmitic acid (PA) is a potential pro-atherogenic stimulus that may aggravate particle-mediated cardiovascular health effects. We hypothesized that the presence of PA can aggravate oxidative stress and endothelial activation induced by multi-walled carbon nanotube (MWCNT) exposure in vitro. We...... measured in the lower chamber on HUVECs and THP-1 cells. The exposure to MWCNTs, including a short (NM400) and long (NM402) type of entangled fibers, was associated with elevated levels of reactive oxygen species as well as a decrease in the intracellular glutathione concentration in HUVEC and A549...

  11. Three-dimensional wet-electrospun poly(lactic acid)/multi-wall carbon nanotubes scaffold induces differentiation of human menstrual blood-derived stem cells into germ-like cells.

    Science.gov (United States)

    Eyni, Hossein; Ghorbani, Sadegh; Shirazi, Reza; Salari Asl, Leila; P Beiranvand, Shahram; Soleimani, Masoud

    2017-09-01

    Infertility caused by the disruption or absence of germ cells is a major and largely incurable medical problem. Germ cells (i.e., sperm or egg) play a key role in the transmission of genetic and epigenetic information across generations. Generation of gametes derived in vitro from stem cells hold promising prospects which could potentially help infertile men and women. Menstrual blood-derived stem cells are a unique stem cell source. Evidence suggests that menstrual blood-derived stem cells exhibit a multi-lineage potential and have attracted extensive attention in regenerative medicine. To maintain the three-dimensional structure of natural extra cellular matrices in vitro, scaffolds can do this favor and mimic a microenvironment for cell proliferation and differentiation. According to previous studies, poly(lactic acid) and multi-wall carbon nanotubes have been introduced as novel and promising biomaterials for the proliferation and differentiation of stem cells. Some cell types have been successfully grown on a matrix containing carbon nanotubes in tissue engineering but there is no report for this material to support stem cells differentiation into germ cells lineage. This study designed a 3D wet-electrospun poly(lactic acid) and poly(lactic acid)/multi-wall carbon nanotubes composite scaffold to compare infiltration, proliferation, and differentiation potential of menstrual blood-derived stem cells toward germ cell lineage with 2D culture. Our primary data revealed that the fabricated scaffold has mechanical and biological suitable qualities for supporting and attachments of stem cells. The differentiated menstrual blood-derived stem cells tracking in scaffolds using scanning electron microscopy confirmed cell attachment, aggregation, and distribution on the porous scaffold. Based on the differentiation assay by RT-PCR analysis, stem cells and germ-like cells markers were expressed in 3D groups as well as 2D one. It seems that poly(lactic acid)/multi-wall

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

    International Nuclear Information System (INIS)

    Lou, J.; Kim, K.-S.

    2008-01-01

    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 μm 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

  13. Electro-optical memory of a nematic liquid crystal doped by multi-walled carbon nanotubes

    Directory of Open Access Journals (Sweden)

    L. Dolgov

    2012-10-01

    Full Text Available A pronounced irreversible electro-optical response (memory effect has been recently observed for nematic liquid crystal (LC EBBA doped by multi-walled carbon nanotubes (MWCNTs near the percolation threshold of the MWCNTs (0.02÷0.05 wt. %. It is caused by irreversible homeotropic-to-planar reorientation of LC in an electric field. This feature is explained by electro-hydrodynamically stimulated dispergation of MWCNTs in LC and by the formation of a percolation MWCNT network which acts as a spatially distributed surface stabilizing the planar state of the LC. This mechanism is confirmed by the absence of memory in the EBBA/MWCNT composites, whose original structure is fixed by a polymer. The observed effect suggests new operation modes for the memory type and bistable LC devices, as well as a method for in situ dispergation of carbon nanotubes in LC cells.

  14. Carcinogenicity of multi-walled carbon nanotubes: challenging issue on hazard assessment.

    Science.gov (United States)

    Fukushima, Shoji; Kasai, Tatsuya; Umeda, Yumi; Ohnishi, Makoto; Sasaki, Toshiaki; Matsumoto, Michiharu

    2018-01-25

    This report reviews the carcinogenicity of multi-walled carbon nanotubes (MWCNTs) in experimental animals, concentrating on MWNT-7, a straight fibrous MWCNT. MWCNTs were administered to mice and rats by intraperitoneal injection, intrascrotal injection, subcutaneous injection, intratracheal instillation and inhalation. Intraperitoneal injection of MWNT-7 induced peritoneal mesothelioma in mice and rats. Intrascrotal injection induced peritoneal mesothelioma in rats. Intratracheal instillation of MWCNT-N (another straight fibrous MWCNT) induced both lung carcinoma and pleural mesothelioma in rats. In the whole body inhalation studies, in mice MWNT-7 promoted methylcholanthrene-initiated lung carcinogenesis. In rats, inhalation of MWNT-7 induced lung carcinoma and lung burdens of MWNT-7 increased with increasing concentration of airborne MWNT-7 and increasing duration of exposure. Straight, fibrous MWCNTs exerted carcinogenicity in experimental animals. Phagocytosis of MWCNT fibers by macrophages was very likely to be a principle factor in MWCNT lung carcinogenesis. Using no-observed-adverse-effect level-based approach, we calculated that the occupational exposure limit (OEL) of MWNT-7 for cancer protection is 0.15 μg/m 3 for a human worker. Further studies on the effects of the shape and size of MWCNT fibers and mode of action on the carcinogenicity are required.

  15. Electrodeposition in the Ni-plating bath containing multi-walled carbon nanotubes

    International Nuclear Information System (INIS)

    An Baigang; Li Lixiang; Li Hongxi

    2008-01-01

    An electrodeposition procedure is performed in the Ni-plating bath containing multi-walled carbon nanotubes (MWNTs). The effects of MWNTs on the electrodeposits and process of Ni deposition are investigated by scanning electron microscopy, X-ray diffraction and electrochemical methods. The results show that there is an optimum concentration of MWNTs, at which the surface of the cathode can be uniformly and completely covered by MWNTs and thus Ni can be uniformly deposited on the MWNTs to form the MWNTs coated with a uniform Ni layer. The introduction of MWNTs in the Ni-plating bath increases the cathodic polarization of Ni deposition due to the two aspects as follows: The addition of MWNTs enhances the charge transfer for the reduction of Ni and also supplies a large active surface area for a great deal of nucleation of Ni, consequently results in an increase of concentration polarization. The deposition of Ni on the MWNTs requires the higher activation energy than that on the Cu. The MWNTs adsorbed on the cathode also induce Ni to deposit as smaller grains due to a large increase of nucleation sites of Ni. Therefore, more uniform and compact coating in appearance than Ni coating formed in the plating bath without MWNTs can be obtained

  16. Plasma-activated multi-walled carbon nanotube-polystyrene composite substrates for biosensing

    International Nuclear Information System (INIS)

    Fernandez-Sanchez, Cesar; Orozco, Jahir; Jimenez-Jorquera, Cecilia; Pellicer, Eva; Lechuga, Laura M; Mendoza, Ernest

    2009-01-01

    Carbon nanotube-polymer composites have shown to be suitable materials for the fabrication of electrochemical transducers. The exposed surface of these materials is commonly passivated by a very thin layer of the polymer component that buries the conductive carbon particles. Working with multi-walled carbon nanotube-polystyrene (MWCNT-PS) composite structures, it was previously described how a simple low power oxygen plasma process produced an effective etching of the composite surface, thereby exposing the conductive surface of CNTs. This work shows how this plasma process not only gave rise to a suitable composite conductive surface for electrochemical sensing but simultaneously exposed and created a high density of oxygen-containing functional groups at both the CNT and the PS components, without affecting the material's mechanical stability. These chemical groups could be effectively modified for the stable immobilization of biological receptors. A detailed chemical characterization of the plasma-activated composite surface was possible using x-ray photoelectron spectroscopy. The material reactivity towards the tethering of a protein was studied and protein-protein interactions were then evaluated on the modified composite transducers by scanning electron microscopy. Finally, an amperometric immunosensor approach for the detection of rabbit Immunoglobulin G target analyte was described and a minimum concentration of 3 ng ml -1 was easily measured.

  17. Plasma-activated multi-walled carbon nanotube-polystyrene composite substrates for biosensing

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-Sanchez, Cesar; Orozco, Jahir; Jimenez-Jorquera, Cecilia [Instituto de Microelectronica de Barcelona, IMB-CNM (CSIC), Campus UAB, E-08193 Bellaterra, Barcelona (Spain); Pellicer, Eva; Lechuga, Laura M; Mendoza, Ernest, E-mail: cesar.fernandez@imb-cnm.csic.e [Nanobiosensors and Molecular Nanobiophysics Group, Research Center on Nanoscience and Nanotechnology (CIN2) CSIC-ICN, ETSE, Campus UAB-Edificio Q, E-08193 Bellaterra, Barcelona (Spain)

    2009-08-19

    Carbon nanotube-polymer composites have shown to be suitable materials for the fabrication of electrochemical transducers. The exposed surface of these materials is commonly passivated by a very thin layer of the polymer component that buries the conductive carbon particles. Working with multi-walled carbon nanotube-polystyrene (MWCNT-PS) composite structures, it was previously described how a simple low power oxygen plasma process produced an effective etching of the composite surface, thereby exposing the conductive surface of CNTs. This work shows how this plasma process not only gave rise to a suitable composite conductive surface for electrochemical sensing but simultaneously exposed and created a high density of oxygen-containing functional groups at both the CNT and the PS components, without affecting the material's mechanical stability. These chemical groups could be effectively modified for the stable immobilization of biological receptors. A detailed chemical characterization of the plasma-activated composite surface was possible using x-ray photoelectron spectroscopy. The material reactivity towards the tethering of a protein was studied and protein-protein interactions were then evaluated on the modified composite transducers by scanning electron microscopy. Finally, an amperometric immunosensor approach for the detection of rabbit Immunoglobulin G target analyte was described and a minimum concentration of 3 ng ml{sup -1} was easily measured.

  18. Dramatic property enhancement in polyetherimide using low-cost commercially functionalized multi-walled carbon nanotubes via a facile solution processing method

    International Nuclear Information System (INIS)

    Kumar, Sandeep; Li Bin; Caceres, Santiago; Zhong Weihong; Maguire, Russ G

    2009-01-01

    Polyetherimide (PEI) has excellent mechanical and thermal properties, and exceptional fire resistance. Developing even broader multi-functionality in PEI/carbon nanotube (CNT) composites for industrial applications is an alluring but challenging goal, due to processing difficulties related to the high pressure and temperature needed to achieve effective flow for this polymer, and costly and complex treatments of the CNTs. Here we report the fabrication of PEI nanocomposite films using low-cost commercially functionalized multi-walled carbon nanotubes (MWNTs), and a simple and innovative process, achieving exceptional properties with only 0.5 wt% of MWNTs, including an increase in electrical conductivity of 12 orders of magnitude, accompanied by an unprecedented increase of 86 0 C in thermal decomposition temperature (higher service temperature). Field emission scanning electron microscopy revealed a high degree of uniform dispersion among the MWNTs, superb polymer-MWNT interaction and formation of a spatially homogeneous nanotube network within the matrix. The enhancement in these properties suggests great potential use for this developed processing approach and the resulting nanocomposites for multi-functional coating or interfacing materials in aerospace and electronic industries.

  19. Windows XP ends its life at CERN – register for Windows 7 training!

    CERN Multimedia

    Michał Kwiatek (IT-OIS)

    2012-01-01

    Windows XP has been around for over 10 years and it is now time to move on. At CERN, general support for Windows XP will end in December 2012, and before this date users are requested to schedule a migration to the next version of WindowsWindows 7.   Windows 7 is already well established at CERN – it is used by a large majority of users. In fact, there was a considerable user demand even before its official release in October 2009 and its adoption has been smooth. Users praise Windows 7 for its improved stability and a clear advantage on laptops is a much more efficient implementation of offline files. The migration to Windows 7 involves a reinstallation of the operating system. Files stored in user home folders on DFS will be immediately available after the reinstallation. Applications will be upgraded to more recent versions and in certain cases, an application may even be replaced by another application providing the same functionality. Microsoft Office suite is a good ...

  20. Extended Plate and Beam Wall System: Concept Investigation and Initial Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Wiehagen, J. [Partnership for Home Innovation, Upper Marlboro, MD (United States); Kochkin, V. [Partnership for Home Innovation, Upper Marlboro, MD (United States)

    2015-08-01

    A new and innovative High-R wall design, referred to as the Extended Plate & Beam (EP&B), is under development. The EP&B system uniquely integrates foam sheathing insulation with wall framing such that wood structural panels are installed exterior of the foam sheathing, enabling the use of standard practices for installation of drainage plane, windows and doors, claddings, cavity insulation, and the standard exterior foam sheathing installation approach prone to damage of the foam during transportation of prefabricated wall panels. As part of the ongoing work, the EP&B wall system concept has undergone structural verification testing and has been positively vetted by a group of industry stakeholders. Having passed these initial milestone markers, the advanced wall system design has been analyzed to assess cost implications relative to other advanced wall systems, undergone design assessment to develop construction details, and has been evaluated to develop representative prescriptive requirements for the building code. This report summarizes the assessment steps conducted to-date and provides details of the concept development.