Sample records for construction materials final

  1. Evaluation of fuel usage factors in highway construction in Oregon : final report.

    DOT National Transportation Integrated Search

    2010-05-01

    Prices for different construction materials change frequently. In recent years, the price for these different materials has dramatically increased. This result leads contractors to inflate the bid price for a construction project in order to cover th...

  2. Mechanical alignment of particles for use in fabricating superconducting and permanent magnetic materials

    DOEpatents

    Nellis, William J.; Maple, M. Brian

    1992-01-01

    A method for mechanically aligning oriented superconducting or permanently magnetic materials for further processing into constructs. This pretreatment optimizes the final crystallographic orientation and, thus, properties in these constructs. Such materials as superconducting fibers, needles and platelets are utilized.

  3. Evaluation and use of the Materials and Test (MATT) Data System for quality of construction and management review : final report.

    DOT National Transportation Integrated Search

    1985-12-01

    This report documents the review of the MATerials and Test (MATT) Data System to check the validity of data within the system. A computer program to generate the quality level of a construction material was developed. Programs were also developed to ...

  4. Formation of optimal construction fleet composition

    NASA Astrophysics Data System (ADS)

    Tuskaeva, Zalina

    2017-10-01

    Machinery supply and its rational use in construction processes considerably determine the final product of construction organizations. Therefore, the problem of defining the type size composition of the construction fleet as one of the lowest material-intensive productions, is of a particular importance.

  5. Experimental evaluation and design of unfilled and concrete-filled FRP composite piles : Task 4B : material & construction specifications : final report.

    DOT National Transportation Integrated Search

    2015-07-01

    The overall goal of this project is the experimental evaluation and design of unfilled and concrete-filled FRP composite piles for load-bearing in bridges. This report covers Task 4B, Materials and Construction Specifications. : This technical report...

  6. Potential for utilizing industrial wastes and by-products in construction of transportation facilities in Virginia : final report.

    DOT National Transportation Integrated Search

    1979-01-01

    This report constitutes: (a) a survey to determine the availability in Virginia of waste materials or by-products that may have a potential for use in highway construction, (b) a summary of published literature concerning the use of waste materials i...

  7. 40 CFR 60.1105 - How do I submit my final materials separation plan?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... for Small Municipal Waste Combustion Units for Which Construction is Commenced After August 30, 1999... part of the notice of construction for the municipal waste combustion unit. Preconstruction...

  8. Summary of tower designs for large horizontal axis wind turbines

    NASA Technical Reports Server (NTRS)

    Frederick, G. R.; Savino, J. M.

    1986-01-01

    Towers for large horizontal axis wind turbines, machines with a rotor axis height above 30 meters and rated at more than 500 kW, have varied in configuration, materials of construction, type of construction, height, and stiffness. For example, the U.S. large HAWTs have utilized steel truss type towers and free-standing steel cylindrical towers. In Europe, the trend has been to use only free-standing and guyed cylindrical towers, but both steel and reinforced concrete have been used as materials of construction. These variations in materials of construction and type of construction reflect different engineering approaches to the design of cost effective towers for large HAWTs. Tower designs are the NASA/DOE Mod-5B presently being fabricated. Design goals and requirements that influence tower configuration, height and materials are discussed. In particular, experiences with United States large wind turbine towers are elucidated. Finally, current trends in tower designs for large HAWTs are highlighted.

  9. Exploration of aggregates in Louisiana : final report.

    DOT National Transportation Integrated Search

    1991-05-01

    Aggregate material deposits which can be processed economically for construction materials are an important resource for the state and the Louisiana Department of Transportation and Development (LADOTD). This need, together with the shortage of aggre...

  10. Geometry control of long-span continuous girder concrete bridge during construction through finite element model updating

    NASA Astrophysics Data System (ADS)

    Wu, Jie; Yan, Quan-sheng; Li, Jian; Hu, Min-yi

    2016-04-01

    In bridge construction, geometry control is critical to ensure that the final constructed bridge has the consistent shape as design. A common method is by predicting the deflections of the bridge during each construction phase through the associated finite element models. Therefore, the cambers of the bridge during different construction phases can be determined beforehand. These finite element models are mostly based on the design drawings and nominal material properties. However, the accuracy of these bridge models can be large due to significant uncertainties of the actual properties of the materials used in construction. Therefore, the predicted cambers may not be accurate to ensure agreement of bridge geometry with design, especially for long-span bridges. In this paper, an improved geometry control method is described, which incorporates finite element (FE) model updating during the construction process based on measured bridge deflections. A method based on the Kriging model and Latin hypercube sampling is proposed to perform the FE model updating due to its simplicity and efficiency. The proposed method has been applied to a long-span continuous girder concrete bridge during its construction. Results show that the method is effective in reducing construction error and ensuring the accuracy of the geometry of the final constructed bridge.

  11. OPTIMIZATION ON MATERIAL FLOW OF NON-METALIC MINERAL MATERIALS TOWARDS SUSTAINABLE SOCIETY

    NASA Astrophysics Data System (ADS)

    Sakamoto, Kouji; Nakayama, Hirofumi; Shimaoka, Takayuki; Hasegawa, Ryoji; Osako, Masahiro

    Since non-metarilc mineral waste such as concrete mass, asphalt concrete mass, sand, slag and coal ash occupies 36% of total amount of waste generation and 26% of total amount of final disposal, it has significant influence on material flow of our country. Although the amount of non-metaril mineral wastes produced is expected to increase in the near future, demand of their application for recycled construction materials will decrease due to the reduction of public construction works and less use of materials in construction. The aim is to reduce environmental load caused by recycling and disposal of non metallic mineral materials, this study was conducted to evaluate the measurement for the reduction of environmental load like landfill amount and CO2 emission amount by controlling material flow of non metallic mineral materials in the year 2030 by linear programming.

  12. High-Fidelity Geometric Modeling and Mesh Generation for Mechanics Characterization of Polycrystalline Materials

    DTIC Science & Technology

    2014-10-26

    From the parameterization results, we extract adaptive and anisotropic T-meshes for the further T- spline surface construction. Finally, a gradient flow...field-based method [7, 12] to generate adaptive and anisotropic quadrilateral meshes, which can be used as the control mesh for high-order T- spline ...parameterization results, we extract adaptive and anisotropic T-meshes for the further T- spline surface construction. Finally, a gradient flow-based

  13. Optimization and management of materials in earthwork construction : final report, April 2010.

    DOT National Transportation Integrated Search

    2010-04-01

    As a result of forensic investigations of problems across Iowa, a research study was developed aimed at providing solutions to identified : problems through better management and optimization of the available pavement geotechnical materials and throu...

  14. Industrial Automation Mechanic Model Curriculum Project. Final Report.

    ERIC Educational Resources Information Center

    Toledo Public Schools, OH.

    This document describes a demonstration program that developed secondary level competency-based instructional materials for industrial automation mechanics. Program activities included task list compilation, instructional materials research, learning activity packet (LAP) development, construction of lab elements, system implementation,…

  15. Zwitterionic materials for antifouling membrane surface construction.

    PubMed

    He, Mingrui; Gao, Kang; Zhou, Linjie; Jiao, Zhiwei; Wu, Mengyuan; Cao, Jialin; You, Xinda; Cai, Ziyi; Su, Yanlei; Jiang, Zhongyi

    2016-08-01

    Membrane separation processes are often perplexed by severe and ubiquitous membrane fouling. Zwitterionic materials, keeping electric neutrality with equivalent positive and negative charged groups, are well known for their superior antifouling properties and have been broadly utilized to construct antifouling surfaces for medical devices, biosensors and marine coatings applications. In recent years, zwitterionic materials have been more and more frequently utilized for constructing antifouling membrane surfaces. In this review, the antifouling mechanisms of zwitterionic materials as well as their biomimetic prototypes in cell membranes will be discussed, followed by the survey of common approaches to incorporate zwitterionic materials onto membrane surfaces including surface grafting, surface segregation, biomimetic adhesion, surface coating and so on. The potential applications of these antifouling membranes are also embedded. Finally, we will present a brief perspective on the future development of zwitterionic materials modified antifouling membranes. Membrane fouling is a severe problem hampering the application of membrane separation technology. The properties of membrane surfaces play a critical role in membrane fouling and antifouling behavior/performance. Antifouling membrane surface construction has evolved as a hot research issue for the development of membrane processes. Zwitterionic modification of membrane surfaces has been recognized as an effective strategy to resist membrane fouling. This review summarizes the antifouling mechanisms of zwitterionic materials inspired by cell membranes as well as the popular approaches to incorporate them onto membrane surfaces. It can help form a comprehensive knowledge about the principles and methods of modifying membrane surfaces with zwitterionic materials. Finally, we propose the possible future research directions of zwitterionic materials modified antifouling membranes. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  16. Market analysis of construction materials with recommendations for the future of the industry : final report, January 14, 2010.

    DOT National Transportation Integrated Search

    2010-01-14

    Due to the volatility of current highway construction commodity prices, owners, contractors, and designers are facing serious challenges in both short-term estimating and long-term planning. Among these challenges is significant uncertainty about the...

  17. Wordburn hot in-plant asphalt pavement recycling project : final report.

    DOT National Transportation Integrated Search

    1992-05-01

    In 1977, the Oregon Department of Transportation constructed a demonstration project using approximately 47,000 tons of stockpiled asphalt concrete (AC) material to overlay a section of pavement in Oregon. The stockpiled AC material was hot in-plant ...

  18. Evaluation of graded limestone base course on a low volume road : final report.

    DOT National Transportation Integrated Search

    1985-04-01

    Due to decreasing supplies of native aggregate which may be incorporated into a base course, other materials need to be evaluated for constructibility and performance. To this end, a graded limestone base was constructed on a low volume road and eval...

  19. Characterization of brominated flame retardants in construction and demolition waste components: HBCD and PBDEs.

    PubMed

    Duan, Huabo; Yu, Danfeng; Zuo, Jian; Yang, Bo; Zhang, Yukui; Niu, Yongning

    2016-12-01

    The vast majority of construction material is inert and can be managed as nonhazardous. However, structures may have either been built with some environmentally unfriendly substances such as brominated flame retardants (BFRs), or have absorbed harmful elements such as heavy metals. This study focuses on end-of-life construction materials, i.e. construction and demolition (C&D) waste components. The aim was to characterize the concentration of extremely harmful substances, primarily BFRs, including hexabromocyclododecane (HBCD) and polybrominateddiphenyl ethers (PBDEs). Results revealed extremely high contents of HBCD and PBDEs in typical C&D waste components, particularly polyurethane foam materials. Policies should therefore be developed for the proper management of C&D waste, with priority for POP-containing debris. The first priority is to develop a classification system and procedures to separate out the harmful materials for more extensive processing. Additionally, identification and quantification of the environmental implications associated with dumping-dominated disposal of these wastes are required. Finally, more sustainable materials should be selected for use in the construction industry. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Wood versus metal in airplane construction

    NASA Technical Reports Server (NTRS)

    Seehase, H

    1923-01-01

    The aim of this article is to present, in broad outline, a scientific method for solving the problem, "Wood or Metal." It will be shown that structural methods have by no means reached their final perfection. The strength of the different materials is discussed as well as different construction methods.

  1. Articulated, Performance-Based Instruction Objectives Guide for Building Construction/Carpentry. Final Document. Revised.

    ERIC Educational Resources Information Center

    Henderson, William Edward, Jr.

    Developed during a project designed to provide continuous, performance-based vocational training at the secondary and postsecondary levels, this instructional guide is intended to help teachers implement a laterally and vertically articulated secondary level building construction/carpentry program. Introductory materials include descriptions of…

  2. Quantify the energy and environmental effects of using recycled asphalt and recycled concrete for pavement construction phase I : final report.

    DOT National Transportation Integrated Search

    2009-08-01

    The objective of this study is to quantify the energy and environment impacts from using recycled materials : for highway construction. Specifically, when recycled asphalt pavement is re-used for producing hot mix : asphalt or when recycled concrete ...

  3. Construction patterns of birds' nests provide insight into nest-building behaviours.

    PubMed

    Biddle, Lucia; Goodman, Adrian M; Deeming, D Charles

    2017-01-01

    Previous studies have suggested that birds and mammals select materials needed for nest building based on their thermal or structural properties, although the amounts or properties of the materials used have been recorded for only a very small number of species. Some of the behaviours underlying the construction of nests can be indirectly determined by careful deconstruction of the structure and measurement of the biomechanical properties of the materials used. Here we examined this idea in an investigation of Bullfinch ( Pyrrhula pyrrhula ) nests as a model for open-nesting songbird species that construct a "twig" nest, and tested the hypothesis that materials in different parts of nests serve different functions. The quantities of materials present in the nest base, sides and cup were recorded before structural analysis. Structural analysis showed that the base of the outer nests were composed of significantly thicker, stronger and more rigid materials compared to the side walls, which in turn were significantly thicker, stronger and more rigid than materials used in the cup. These results suggest that the placement of particular materials in nests may not be random, but further work is required to determine if the final structure of a nest accurately reflects the construction process.

  4. Development and construction of low-cracking high-performance concrete (LC-HPC) bridge decks : free shrinkage, moisture optimization and concrete production : final report.

    DOT National Transportation Integrated Search

    2009-08-01

    The development and evaluation of low-cracking high-performance concrete (LC-HPC) for use in bridge decks : is described based on laboratory test results and experience gained during the construction of 14 bridges. This report : emphasizes the materi...

  5. Trace radioactive impurities in final construction materials for EXO-200

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Leonard, D. S.; Auty, D. J.; Didberidze, T.

    Here, we report results from a systematic measurement campaign conducted to identify low radioactivity materials for the construction of the EXO-200 double beta decay experiment. Partial results from this campaign have already been reported in a 2008 paper by the EXO collaboration. Here we release the remaining data, collected since 2007, to the public. The data reported were obtained using a variety of analytic techniques. The measurement sensitivities are among the best in the field. We concluded the construction of the EXO-200 detector and Phase-I data was taken from 2011 to 2014. The detector’s extremely low background implicitly verifies themore » measurements and the analysis assumptions made during construction and reported in this paper.« less

  6. Trace radioactive impurities in final construction materials for EXO-200

    DOE PAGES

    Leonard, D. S.; Auty, D. J.; Didberidze, T.; ...

    2017-05-01

    Here, we report results from a systematic measurement campaign conducted to identify low radioactivity materials for the construction of the EXO-200 double beta decay experiment. Partial results from this campaign have already been reported in a 2008 paper by the EXO collaboration. Here we release the remaining data, collected since 2007, to the public. The data reported were obtained using a variety of analytic techniques. The measurement sensitivities are among the best in the field. We concluded the construction of the EXO-200 detector and Phase-I data was taken from 2011 to 2014. The detector’s extremely low background implicitly verifies themore » measurements and the analysis assumptions made during construction and reported in this paper.« less

  7. Final Environmental Assessment: For Construction of a Security Forces Complex on Eglin Air Force Base, FL

    DTIC Science & Technology

    2005-05-01

    form of weapons cleaning products and wastes. State of Florida and Air Force regulations have been implemented 05/31/05 Final Environmental Assessment...Forces Complex will generate hazardous materials in the form of weapons cleaning products and wastes. Break-Free CLP Liquid is a cleaner, lubricant

  8. Evaluation of a Variable-Impedance Ceramic Matrix Composite Acoustic Liner

    NASA Technical Reports Server (NTRS)

    Jones, M. G.; Watson, W. R.; Nark, D. M.; Howerton, B. M.

    2014-01-01

    As a result of significant progress in the reduction of fan and jet noise, there is growing concern regarding core noise. One method for achieving core noise reduction is via the use of acoustic liners. However, these liners must be constructed with materials suitable for high temperature environments and should be designed for optimum absorption of the broadband core noise spectrum. This paper presents results of tests conducted in the NASA Langley Liner Technology Facility to evaluate a variable-impedance ceramic matrix composite acoustic liner that offers the potential to achieve each of these goals. One concern is the porosity of the ceramic matrix composite material, and whether this might affect the predictability of liners constructed with this material. Comparisons between two variable-depth liners, one constructed with ceramic matrix composite material and the other constructed via stereolithography, are used to demonstrate this material porosity is not a concern. Also, some interesting observations are noted regarding the orientation of variable-depth liners. Finally, two propagation codes are validated via comparisons of predicted and measured acoustic pressure profiles for a variable-depth liner.

  9. Students’ planetarium

    NASA Astrophysics Data System (ADS)

    Brozis, Mirosław; Świderski, Kamil

    2018-05-01

    Our students built a full-size, mobile planetarium in three weeks. The planetarium was built with commonly available, cheap construction materials. Our priorities were mobility, possibility of quick assembly and reassembly and the students’ availability of materials in every place in the world. The students calculated all the parameters of the planetarium’s construction themselves, chose materials of appropriate technical parameters, built the planetarium’s framework, elaborated the methods of projections and sounding. Taking into consideration the spectators’ comfort they also designed systems of air conditioning and cooling. The project is completely consistent with the STEM and even the STEAM method. The artistic factor of the students’ work was revealed during the visualisation of planetarium projections and its adornment. The final product of their work is a functional planetarium and a manual for its construction.

  10. Construction patterns of birds’ nests provide insight into nest-building behaviours

    PubMed Central

    Goodman, Adrian M.

    2017-01-01

    Previous studies have suggested that birds and mammals select materials needed for nest building based on their thermal or structural properties, although the amounts or properties of the materials used have been recorded for only a very small number of species. Some of the behaviours underlying the construction of nests can be indirectly determined by careful deconstruction of the structure and measurement of the biomechanical properties of the materials used. Here we examined this idea in an investigation of Bullfinch (Pyrrhula pyrrhula) nests as a model for open-nesting songbird species that construct a “twig” nest, and tested the hypothesis that materials in different parts of nests serve different functions. The quantities of materials present in the nest base, sides and cup were recorded before structural analysis. Structural analysis showed that the base of the outer nests were composed of significantly thicker, stronger and more rigid materials compared to the side walls, which in turn were significantly thicker, stronger and more rigid than materials used in the cup. These results suggest that the placement of particular materials in nests may not be random, but further work is required to determine if the final structure of a nest accurately reflects the construction process. PMID:28265501

  11. Types of architectural structures and the use of smart materials

    NASA Astrophysics Data System (ADS)

    Tavşan, Cengiz; Sipahi, Serkan

    2017-07-01

    The developments in technology following the industrial revolution had their share of impact on both construction techniques, and material technologies. The change in the materials used by the construction industry brought along numerous innovations, which, in turn, took on an autonomous trend of development given the rise of nano-tech materials. Today, nano-tech materials are used extensively in numerous construction categories. Nano-tech materials, in general, are characterized by their reactionary nature, with the intent of repeating the reactions again and again under certain conditions. That is why nano-tech materials are often called smart materials. In construction industry, smart materials are categorized under 4 major perspectives: Shape-shifting smart materials, power generating smart materials, self-maintenance smart materials, and smart materials providing a high level of insulation. In architecture, various categories of construction often tend to exhibit their own approaches to design, materials, and construction techniques. This is a direct consequence of the need for different solutions for different functions. In this context, the use of technological materials should lead to the use of a set of smart materials for a given category of structures, while another category utilizes yet another set. In the present study, the smart materials used in specific categories of structures were reviewed with reference to nano-tech practices implemented in Europe, with a view to try and reveal the changes in the use of smart materials with reference to categories of structures. The study entails a discussion to test the hypothesis that nano-tech materials vary with reference to structure categories, on the basis of 18 examples from various structure categories, built by the construction firms with the highest level of potential in terms of doing business in Europe. The study comprises 3 major sections: The first section reiterates what the literature has to say about smart materials; the second discusses the types and characteristics of smart materials over the tables detailing their utilization and functions in the structures included in the set of examples. The final section of the study, on the other hand, elaborates on the findings, discussing them with reference to the types of structures.

  12. Data Base Descriptors for Electro-Optical Sensor Simulation. Final Report, May 1977 through June 1978.

    ERIC Educational Resources Information Center

    Zimmerlin, Timothy A.; And Others

    An effort to construct a model of the thermal properties of materials based on theoretical thermo-electromagnetic models, to construct a data base of the dense cultural hospital scene according to Defense Mapping Agency Aerospace Center (DMAAC) specifications, and to design and implement a program to evaluate the tonal model and generate imagery…

  13. Environmental and economic evaluation of natural capital appropriation through building construction: practical case study in the Italian context.

    PubMed

    Bastianoni, Simone; Galli, Alessandro; Pulselli, Riccardo Maria; Niccolucci, Valentina

    2007-11-01

    This paper focuses on appropriation of natural capital through construction of buildings. The ecological footprint and the Costanza natural capital concepts are applied. The environmental consequences of human settlement are currently of great concern, and a need is felt to reduce the impact of building on the environment. The embodied energy of building materials and the "land area" required to sustain their production are considered to evaluate the demand on nature of this activity. The ecological footprints of 2 typical Italian buildings are compared. The paper also focuses on how to reduce the natural capital appropriation of building construction by means of environmentally inexpensive materials, renewable energy resources, and optimization of the use of bioproductive land by construction of multistoried buildings. Finally, to allocate an environmental load of buildings, an economic evaluation of natural capital appropriation through building construction is proposed.

  14. Approximate static condensation algorithm for solving multi-material diffusion problems on meshes non-aligned with material interfaces

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kikinzon, Evgeny; Kuznetsov, Yuri; Lipnikov, Konstatin

    In this study, we describe a new algorithm for solving multi-material diffusion problem when material interfaces are not aligned with the mesh. In this case interface reconstruction methods are used to construct approximate representation of interfaces between materials. They produce so-called multi-material cells, in which materials are represented by material polygons that contain only one material. The reconstructed interface is not continuous between cells. Finally, we suggest the new method for solving multi-material diffusion problems on such meshes and compare its performance with known homogenization methods.

  15. Approximate static condensation algorithm for solving multi-material diffusion problems on meshes non-aligned with material interfaces

    DOE PAGES

    Kikinzon, Evgeny; Kuznetsov, Yuri; Lipnikov, Konstatin; ...

    2017-07-08

    In this study, we describe a new algorithm for solving multi-material diffusion problem when material interfaces are not aligned with the mesh. In this case interface reconstruction methods are used to construct approximate representation of interfaces between materials. They produce so-called multi-material cells, in which materials are represented by material polygons that contain only one material. The reconstructed interface is not continuous between cells. Finally, we suggest the new method for solving multi-material diffusion problems on such meshes and compare its performance with known homogenization methods.

  16. The Utilization of Graphene Oxide in Traditional Construction Materials: Asphalt.

    PubMed

    Zeng, Wenbo; Wu, Shaopeng; Pang, Ling; Sun, Yihan; Chen, Zongwu

    2017-01-07

    In the advanced research fields of solar cell and energy storing materials, graphene and graphene oxide (GO) are two of the most promising materials due to their high specific surface area, and excellent electrical and physical properties. However, they was seldom studied in the traditional materials because of their high cost. Nowadays, graphene and GO are much cheaper than before with the development of production technologies, which provides the possibility of using these extraordinary materials in the traditional construction industry. In this paper, GO was selected as a nano-material to modify two different asphalts. Then a thin film oven test and a pressure aging vessel test were applied to simulate the aging of GO-modified asphalts. After thermal aging, basic physical properties (softening point and penetration) were tested for the samples which were introduced at different mass ratios of GO (1% and 3%) to asphalt. In addition, rheological properties were tested to investigate how GO could influence the asphalts by dynamic shearing rheometer tests. Finally, some interesting findings and potential utilization (warm mixing and flame retardants) of GO in asphalt pavement construction were explained.

  17. The Utilization of Graphene Oxide in Traditional Construction Materials: Asphalt

    PubMed Central

    Zeng, Wenbo; Wu, Shaopeng; Pang, Ling; Sun, Yihan; Chen, Zongwu

    2017-01-01

    In the advanced research fields of solar cell and energy storing materials, graphene and graphene oxide (GO) are two of the most promising materials due to their high specific surface area, and excellent electrical and physical properties. However, they was seldom studied in the traditional materials because of their high cost. Nowadays, graphene and GO are much cheaper than before with the development of production technologies, which provides the possibility of using these extraordinary materials in the traditional construction industry. In this paper, GO was selected as a nano-material to modify two different asphalts. Then a thin film oven test and a pressure aging vessel test were applied to simulate the aging of GO-modified asphalts. After thermal aging, basic physical properties (softening point and penetration) were tested for the samples which were introduced at different mass ratios of GO (1% and 3%) to asphalt. In addition, rheological properties were tested to investigate how GO could influence the asphalts by dynamic shearing rheometer tests. Finally, some interesting findings and potential utilization (warm mixing and flame retardants) of GO in asphalt pavement construction were explained. PMID:28772406

  18. Bioink properties before, during and after 3D bioprinting.

    PubMed

    Hölzl, Katja; Lin, Shengmao; Tytgat, Liesbeth; Van Vlierberghe, Sandra; Gu, Linxia; Ovsianikov, Aleksandr

    2016-09-23

    Bioprinting is a process based on additive manufacturing from materials containing living cells. These materials, often referred to as bioink, are based on cytocompatible hydrogel precursor formulations, which gel in a manner compatible with different bioprinting approaches. The bioink properties before, during and after gelation are essential for its printability, comprising such features as achievable structural resolution, shape fidelity and cell survival. However, it is the final properties of the matured bioprinted tissue construct that are crucial for the end application. During tissue formation these properties are influenced by the amount of cells present in the construct, their proliferation, migration and interaction with the material. A calibrated computational framework is able to predict the tissue development and maturation and to optimize the bioprinting input parameters such as the starting material, the initial cell loading and the construct geometry. In this contribution relevant bioink properties are reviewed and discussed on the example of most popular bioprinting approaches. The effect of cells on hydrogel processing and vice versa is highlighted. Furthermore, numerical approaches were reviewed and implemented for depicting the cellular mechanics within the hydrogel as well as for prediction of mechanical properties to achieve the desired hydrogel construct considering cell density, distribution and material-cell interaction.

  19. Construction and demolition waste as a source of PVC for recycling.

    PubMed

    Prestes, Sabrina Moretto Darbello; Mancini, Sandro Donnini; Rodolfo, Antonio; Keiroglo, Raquel Carramillo

    2012-02-01

    Construction and demolition waste can contain considerable amounts of polyvinyl chloride (PVC). This paper describes a study of the recycling of PVC pipes collected from such waste materials. In a sorting facility for the specific disposal of construction and demolition waste, PVC was found to represent one-third of the plastics separated by workers. Pipes were sorted carefully to preclude any possible contamination by poly(ethylene terephthalate) (PET) found in the waste. The material was ground into two distinct particle sizes (final mesh of 12.7 and 8 mm), washed, dried and recycled. The average formulation of the pipes was determined based on ash content tests and used in the fabrication of a similar compound made mainly of virgin PVC. Samples of recycled pipes and of compound based on virgin material were subjected to tensile and impact tests and provided very similar results. These results are a good indication of the application potential of the recycled material and of the fact that longer grinding to obtain finer particles is not necessarily beneficial.

  20. Research on test of alkali-resistant glass fibre enhanced seawater coral aggregate concrete

    NASA Astrophysics Data System (ADS)

    Liu, Leiyang; Wang, Xingquan

    2017-12-01

    It is proposed in the 13th five-year plan that reefs of the south China sea should be constructed. In the paper, an innovative thinking was proposed for the first time in order to realize local material acquisition in island construction and life dependence on sea, namely alkali-resistant glass fibre is mixed in coralaggregate concrete as reinforcing material. The glass fibre is characterized by low price, low hardness, good dispersibility and convenient construction. Reliable guarantee is provided for widely applying the material in future projects. In the paper, an orthogonal test method is firstly applied to determine the mix proportion of grade C50 coral aggregate concrete. Then, the design plan ofmix proportion of alkali-resistant glass fibre enhanced seawater coral aggregate concrete is determined. Finally, the influence law of alkali-resistant glass fibre dosageon tensile compressiveflexture strength of seawatercoralaggregate concrete is made clear.

  1. STUDY ON THE REDUCTION MEASURES OF ENVIRONMENTAL LOADS AT THE DESIGNING AND CONSTRUCTION STAGES OF THE RIVER WORKS

    NASA Astrophysics Data System (ADS)

    Ikeda, Tetsuya; Amano, Kunihiko; Kishida, Hiroyuki

    In the field of infrastructure construction including river works, construction materials such as concrete are used, and it needs to transport them for the long distance. Due to recent growth of public awareness on the environmental issues, it becomes more important to estimate and reduce the environmental loads brought by the infrastructure construction. In the infrastructure construction, it is necessary to take notice of carbon dioxide and waste materials as the broad-based and long-range environmental loads. On the other hand, it is necessary to conduct the quantitative evaluation on these environmental loads and to investigate the reduction measures by considering the actual situation of construction. Focusing on the river works, this paper estimates the cost of construction, the carbon dioxide emission and final disposal volume on the several alternative plans at the designing stage, compares the significance of different environmental loads by using the integrated factors of LIME2, and analyzes the effectiveness of reduction measures. It also establishes the reduction scenarios of the environmental loads, and analyzes the effectiveness compared to the base-line scenario in which the materials are newly extracted and produced. Based on the results, it establishes the procedure intending to reduce the environmental loads at the time of river planning and construction, which will be referentialized by river managers, construction consultants and constructors nationwide.

  2. GIS-based planning system for managing the flow of construction and demolition waste in Brazil.

    PubMed

    Paz, Diogo Henrique Fernandes da; Lafayette, Kalinny Patrícia Vaz; Sobral, Maria do Carmo

    2018-05-01

    The objective of this article was to plan a network for municipal management of construction and demolition waste in Brazil with the assistance of a geographic information system, using the city of Recife as a case study. The methodology was carried out in three stages. The first was to map the illegal construction and demolition of waste disposal points across Recife and classify the waste according to its recyclability. In sequence, a method for indicating suitable areas for installation of voluntary delivery points, for small waste generators, are presented. Finally, a method for indicating suitable areas for the installation of trans-shipment and waste sorting areas, developed for large generators, is presented. The results show that a geographic information system is an essential tool in the planning of municipal construction and demolition waste management, in order to facilitate the spatial analysis and control the generation, sorting, collection, transportation, and final destination of construction and demolition waste, increasing the rate of recovery and recycling of materials.

  3. Hybrid Physical Vapor Deposition Instrument for Advanced Functional Multilayers and Materials

    DTIC Science & Technology

    2016-04-27

    Hybrid Physical Vapor Deposition Instrument for Advanced Functional Multilayers and Materials PI Maria received support to construct a physical... vapor deposition (PVD) system that combines electron beam (e- beam) evaporation, magnetron sputtering, pulsed laser ablation, and ion-assisted deposition ...peer-reviewed journals: Number of Papers published in non peer-reviewed journals: Final Report: Hybrid Physical Vapor Deposition Instrument for Advanced

  4. Lime Kiln Dust for Treated Subgrades : Final Report

    DOT National Transportation Integrated Search

    2017-11-01

    Chemical and cementitious materials are often used to modify and stabilize the subgrade soils that serve as foundations for pavements. Improvement of the subgrade provides a better working platform for construction of the layers above and improves th...

  5. The Mini-Earth facility and present status of habitation experiment program.

    PubMed

    Nitta, Keiji

    2005-01-01

    The history of construction of the CEEF (the Mini-Earth), the configuration and scale of the CEEF are initially described. The effective usable areas in plant cultivation and animal holding and habitation modules and the accommodation equipment installed in each module are also explained. Mechanisms of the material circulation systems belonging to each module and subsystems in each material circulation system are introduced. Finally the results of pre-habitation experiments conducted until the year 2004 for clarifying the requirements in order to promote final closed habitation experiments are shown. c2005 Published by Elsevier Ltd on behalf of COSPAR.

  6. Use of maxillofacial laboratory materials to construct a tissue-equivalent head phantom with removable titanium implantable devices for use in verification of the dose of intensity-modulated radiotherapy.

    PubMed

    Morris, K

    2017-06-01

    The dose of radiotherapy is often verified by measuring the dose of radiation at specific points within a phantom. The presence of high-density implant materials such as titanium, however, may cause complications both during calculation and delivery of the dose. Numerous studies have reported photon/electron backscatter and alteration of the dose by high-density implants, but we know of no evidence of a dosimetry phantom that incorporates high density implants or fixtures. The aim of the study was to design and manufacture a tissue-equivalent head phantom for use in verification of the dose in radiotherapy using a combination of traditional laboratory materials and techniques and 3-dimensional technology that can incorporate titanium maxillofacial devices. Digital designs were used together with Mimics® 18.0 (Materialise NV) and FreeForm® software. DICOM data were downloaded and manipulated into the final pieces of the phantom mould. Three-dimensional digital objects were converted into STL files and exported for additional stereolithography. Phantoms were constructed in four stages: material testing and selection, design of a 3-dimensional mould, manufacture of implants, and final fabrication of the phantom using traditional laboratory techniques. Three tissue-equivalent materials were found and used to successfully manufacture a suitable phantom with interchangeable sections that contained three versions of titanium maxillofacial implants. Maxillofacial and other materials can be used to successfully construct a head phantom with interchangeable titanium implant sections for use in verification of doses of radiotherapy. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  7. Nitrogen dioxide sequestration using demolished concrete and its potential application in transportation infrastructure development : final report.

    DOT National Transportation Integrated Search

    2016-04-01

    Achieving environmental sustainability of the US transportation infrastructure via more environmentally sound construction is not a trivial task. Our : proposal, which addresses this critical area, is aiming at transforming concrete, the material of ...

  8. Partial polarization: a comprehensive student exercise

    NASA Astrophysics Data System (ADS)

    Topasna, Gregory A.; Topasna, Daniela M.

    2015-10-01

    We present a comprehensive student exercise in partial polarization. Students are first introduced to the concept of partial polarization using Fresnel Equations. Next, MATHCAD is used to compute and graph the reflectance for dielectrics materials. The students then design and construct a simple, easy to use collimated light source for their experiment, which is performed on an optical breadboard using optical components typically found in an optics lab above the introductory level. The students obtain reflection data that is compared with their model by a nonlinear least square fit using EXCEL. Sources of error and uncertainty are discussed and students present a final written report. In this one exercise students learn how an experiment is constructed "from the ground up". They gain practical experience on data modeling and analysis, working with optical equipment, machining and construction, and preparing a final presentation.

  9. Experimental use of geogrids as an alternative to gravel placement : fourth year interim and final report, October 2006.

    DOT National Transportation Integrated Search

    2006-10-01

    With the ongoing demand for improved infrastructure, the Maine Department of Transportation : (MaineDOT) continues to identify and evaluate new and innovative construction methods and materials. : The Departments Collector Highway Improvement Prog...

  10. Fatigue study of a GRP pedestrian bridge : final report.

    DOT National Transportation Integrated Search

    1986-01-01

    Static and cyclic load tests were conducted on a 16-ft long bridge constructed with fiberglass materials. Approximately 1.6 million cycles of loads were applied to the deck to study the fatigue characteristics of the bridge. The location and magnitud...

  11. Development, characterization and applications of a non proprietary ultra high performance concrete for highway bridges : final report.

    DOT National Transportation Integrated Search

    2016-03-14

    Ultra-high performance concrete (UHPC) is a new class of cementitious materials that have : exceptional mechanical and durability characteristics. UHPC is commercially available. : However, its cost for construction of highway structures is prohibiti...

  12. Volatile organic compounds concentrations during the construction process in newly-built timber-frame houses: source identification and emission kinetics.

    PubMed

    Plaisance, H; Vignau-Laulhere, J; Mocho, P; Sauvat, N; Raulin, K; Desauziers, V

    2017-05-24

    Building and furniture materials are known to be major sources of volatile organic compounds (VOCs) indoors. During the construction process, an introduced material can have a more or less long-term impact on the indoor air quality according to the building characteristics. In this study, field measurements were carried out at six construction stages in three energy-efficient timber-frame houses. Data analysis focused on the ten most abundant compounds found among an initial list of fifteen target VOCs, namely formaldehyde, acetaldehyde, hexanal, toluene, m/p-xylenes, ethylbenzene, styrene, α-pinene, 3-carene and d-limonene. The chemical compositions and concentration variation patterns were recorded. The results showed a high pollution count, with m/p-xylenes and ethylbenzene concentrations ranging from 1900 to 5100 μg m -3 occurring at the time of the structural work (representing more than 88% of the sum of the target VOCs). Emission tests done on a large number of materials used in the construction revealed that this pollution is due to the emissions from the polyurethane adhesive mastic used as a sealing material. The emission kinetics of polyurethane adhesive mastic was assessed alone and also within a material assembly reconstituting a room wall. The results showed that the superposition of materials led to a slowing down of the VOC emission process from polyurethane adhesive mastic, which explains the concentration decays recorded in houses during the construction process. At the final construction stage, the concentration levels were low for all compounds (the sums of the target VOCs were between 18 and 32 μg m -3 ), with the aldehydes (formaldehyde, acetaldehyde and hexanal) now becoming the major fraction in the chemical composition in the last stages of construction (representing 50-70% of the sum of the target VOCs). This is in agreement with the fact that the sources of aldehydes are the most numerous among the materials and have rather slow emission kinetics.

  13. Optimality of Thermal Expansion Bounds in Three Dimensions

    DOE PAGES

    Watts, Seth E.; Tortorelli, Daniel A.

    2015-02-20

    In this short note, we use topology optimization to design multi-phase isotropic three-dimensional composite materials with extremal combinations of isotropic thermal expansion and bulk modulus. In so doing, we provide evidence that the theoretical bounds for this combination of material properties are optimal. This has been shown in two dimensions, but not heretofore in three dimensions. Finally, we also show that restricting the design space by enforcing material symmetry by construction does not prevent one from obtaining extremal designs.

  14. Rare and Rare-Earth Metals in Coal Processing Waste

    NASA Astrophysics Data System (ADS)

    Cherkasova, Tatiana; Cherkasova, Elizaveta; Tikhomirova, Anastasia; Bobrovni-kova, Alyona; Goryunova, Irina

    2017-11-01

    An urgent issue for power plants operating on solid fuels (coal) is the issue of utilization or use of accumulated production waste - ash and slag materials - in the related production. Ash-slag materials are classified as "waste", usually grade 5; tens of millions of tons of them being pro-duced annually in the Kemerovo region, which threatens the ecology of the region. At the same time, ash and slag is a very promising raw material. The use of this material as a base for the final product allows us to signifi-cantly expand the possibilities of using coal. The most widespread is the system of ash and slag involving in construction or as a replacement for sand in road construction, or as an additive to building mixtures. However, there are both industrially valuable and environmentally dangerous ele-ments in ash-slag materials. Ash-slag materials can be considered as inde-pendent ore deposits located on the surface and requiring the costs of their extraction.

  15. Field evaluation of fly ash in aggregate shoulder materials : final report.

    DOT National Transportation Integrated Search

    1985-06-01

    This study consisted of an evaluation of self-hardening fly ash (Class C) used as an additive in the treatment of shoulders surfaced with sand clay gravel and/or shell (oyster). This was accomplished through construction of fly ash treated aggregate ...

  16. Design and development of data acquisition system for the Louisiana accelerated loading device : final report.

    DOT National Transportation Integrated Search

    1992-09-01

    The Louisiana Transportation Research Center has established a Pavement Research Facility (PRF). The core of the PRF is a testing machine that is capable of conducting full-scale simulated and accelerated load testing of pavement materials, construct...

  17. 23 CFR 771.113 - Timing of Administration activities.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... a finding of no significant impact (FONSI) or a record of decision (ROD) and comply with other related environmental laws and regulations to the maximum extent possible during the NEPA process. This... involvement. However, final design activities, property acquisition, purchase of construction materials or...

  18. Evaluation of a metal fuselage frame selectively reinforced with filamentary composites for space shuttle application

    NASA Technical Reports Server (NTRS)

    Oken, S.; Skoumal, D. E.; Straayer, J. W.

    1974-01-01

    The development of metal structures reinforced with filamentary composites as a weight saving feature of the space shuttle components is discussed. A frame was selected for study that was representative of the type of construction used in the bulk frames of the orbiter vehicle. Theoretical and experimental investigations were conducted. Component tests were performed to evaluate the critical details used in the designs and to provide credibility to the weight saving results. A model frame was constructed of the reinforced metal material to provide a final evaluation of the construction under realistic load conditions.

  19. Correlation of rapid hydrometer analysis for select material to existing procedure LDH-TR-407-66 : final report.

    DOT National Transportation Integrated Search

    1968-05-01

    Conditions arise during construction of bases with Portland cement stabilized soils which require close programming of work. Therefore, time is of significant importance. : That is the objective of this report; to evaluate a method by which considera...

  20. Large Wind Energy Converter: Growian 3 MW

    NASA Technical Reports Server (NTRS)

    Feustel, J. E.; Helm, S.; Koerber, F.

    1980-01-01

    The final report on the projected application of larger-scale wind turbine on the northern German coast is summarized. The designs of the tower, machinery housing, rotor, and rotor blades are described accompanied various construction materials are examined. Rotor blade adjustment devices auxiliary and accessory equipment are examined.

  1. Study Of Pre-Shaped Membrane Mirrors And Electrostatic Mirrors With Nonlinear-Optical Correction

    DTIC Science & Technology

    2002-01-01

    mirrors have been manufactured of glass-like material Zerodur with very low coefficient of linear expansion. They have a more light cellular construction...primary and flat secondary mirrors are both segmented ones. In the case of the primary mirror made of traditional materials such as Zerodur or fused...FINAL REPORT ISTC Project #2103p “Study of Pre-Shaped Membrane Mirrors and Electrostatic Mirrors with Nonlinear-Optical Correction” Manager

  2. Literacy Is VITAL. Final Report.

    ERIC Educational Resources Information Center

    Gillfillan, Nancy M.

    Via an LSCA (Library Services and Construction Act) Title VI Library Literacy grant for fiscal year 1986, the Dixon (Illinois) Public Library expanded its involvement in the literacy effort. Additional rooms were made available for tutoring, materials and equipment for literacy students and books and equipment for literacy tutors were provided,…

  3. 76 FR 32867 - Hazardous Materials: Requirements for Storage of Explosives During Transportation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-07

    ... from release into the environment. This final rule does not prohibit or promote the development of safe... Association Standard (NFPA) 498--Standard for Safe Havens and Interchange Lots for Vehicles Transporting Explosives (2010 Edition) for the construction and maintenance of safe havens used for unattended storage of...

  4. Combined research effort on aggregate road materials

    NASA Astrophysics Data System (ADS)

    Kuznetsova, Elena; Hoff, Inge; Willy Danielsen, Svein; Wigum, Børge Johannes; Fladvad, Marit; Rieksts, Karlis; Loranger, Benoit; Barbieri, Diego

    2017-04-01

    In European countries, the average aggregate consumption per capita is 5 tons per year (European Aggregates Association 2016), while the corresponding number in Norway is 11 tons (Neeb 2015). Due to the increased demand for sand and gravel for construction purposes, e.g. in road construction, the last decade has seen a significant trend towards the use of crushed rock aggregates. Neeb (2015) reports that half of the Norwegian aggregate production (sand, gravel and crushed rock) is used for road construction, and 33 % of the overall sold tonnage of crushed rock is exported. This resource has been more and more preferred over sand and gravel due to the significant technological development of its process and utilization phase. In Norway, the development and implementation of crushed aggregate technology has been the main approach to solve natural resource scarcity (Danielsen and Kuznetsova 2015). In order to reduce aggregates transportation, it is aimed to use local aggregates and aggregates processed from rock excavations, tunneling, road cuts, etc. One issue focused in this research is the influence from blasting and processing on the final quality of the crushed aggregates, specifically relating to the properties for road construction purposes. It is therefor crucial to plan utilization of available materials for use in different road layers following the same production line. New developments and improved availability of mobile crushing and screening equipment could produce more sustainable and profitable sources of good quality aggregate materials from small volume deposits in proximity to construction sites. One of the biggest challenges today to use these materials is that the pavement design manual sets rigid requirements for pavement layers. Four research projects are being conducted in Norway to improve the use of local materials for road construction. Four aspects are to be covered by the research: a) geological characteristics of the materials, their b) mechanical and c) thermal properties, and d) frost action and susceptibility. The main goal of the PhD topic N1 is to achieve better utilization of aggregate resources through adjusting the production process according to local geological conditions and construction needs. The objective of the PhD project N2 is to look at the design stage and find the way to use these aggregates anyway by changing the road's design (e.g. increasing the thickness of asphalt layer). Fine particles content will also be harder to control due to rock type variability from site to site. Thus, PhD project N3 is going to investigate the effect of the increasing of fines and their mineralogy on frost action related problems during freezing and thawing seasons. Finally, PhD project N4 is investigating how the grading and mineralogy of the crushed rock material affects the heat exchange in road's granular layers and consequently, the frost penetration depth. Combining these PhD studies we aim to create a holistic approach for a new understanding within this very complex area.

  5. U.S.-Coalition Forces and Host Nations: DOTmLPF-P for Contingency Procurements. Part 2. Conclusion

    DTIC Science & Technology

    2014-08-01

    doesn’t have to be stood up. Examples include textile/cloth- ing/ footwear , construction, and furniture, industries that usu- ally exist in some...meet its needs but be within the HNVs’ capability to manufacture. Finally, materials used by HNVs to manufacture products under U.S. or HNG...procurement efforts should come from reliable sources with processes and physical features in place to prevent substandard or fake material from entering the

  6. The New Field Quantities and the Poynting Theorem in Material Medium with Magnetic Monopoles

    NASA Astrophysics Data System (ADS)

    Zor, Ömer

    2016-12-01

    The duality transformation was used to define the polarization mechanisms that arise from magnetic monopoles. Then, a dimensional analysis was conducted to describe the displacement and magnetic intensity vectors (constitutive equations) in SI units. Finally, symmetric Maxwell equations in a material medium with new field quantities were introduced. Hence, the Lorentz force and the Poynting theorem were defined with these new field quantities, and many possible definitions of them were constructed.

  7. Field-gradient partitioning for fracture and frictional contact in the material point method: Field-gradient partitioning for fracture and frictional contact in the material point method [Fracture and frictional contact in material point method using damage-field gradients for velocity-field partitioning

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Homel, Michael A.; Herbold, Eric B.

    Contact and fracture in the material point method require grid-scale enrichment or partitioning of material into distinct velocity fields to allow for displacement or velocity discontinuities at a material interface. We present a new method which a kernel-based damage field is constructed from the particle data. The gradient of this field is used to dynamically repartition the material into contact pairs at each node. Our approach avoids the need to construct and evolve explicit cracks or contact surfaces and is therefore well suited to problems involving complex 3-D fracture with crack branching and coalescence. A straightforward extension of this approachmore » permits frictional ‘self-contact’ between surfaces that are initially part of a single velocity field, enabling more accurate simulation of granular flow, porous compaction, fragmentation, and comminution of brittle materials. Finally, numerical simulations of self contact and dynamic crack propagation are presented to demonstrate the accuracy of the approach.« less

  8. Field-gradient partitioning for fracture and frictional contact in the material point method: Field-gradient partitioning for fracture and frictional contact in the material point method [Fracture and frictional contact in material point method using damage-field gradients for velocity-field partitioning

    DOE PAGES

    Homel, Michael A.; Herbold, Eric B.

    2016-08-15

    Contact and fracture in the material point method require grid-scale enrichment or partitioning of material into distinct velocity fields to allow for displacement or velocity discontinuities at a material interface. We present a new method which a kernel-based damage field is constructed from the particle data. The gradient of this field is used to dynamically repartition the material into contact pairs at each node. Our approach avoids the need to construct and evolve explicit cracks or contact surfaces and is therefore well suited to problems involving complex 3-D fracture with crack branching and coalescence. A straightforward extension of this approachmore » permits frictional ‘self-contact’ between surfaces that are initially part of a single velocity field, enabling more accurate simulation of granular flow, porous compaction, fragmentation, and comminution of brittle materials. Finally, numerical simulations of self contact and dynamic crack propagation are presented to demonstrate the accuracy of the approach.« less

  9. Supplementary Materials for State Penitentiary Library Project. Final Performance Report.

    ERIC Educational Resources Information Center

    Hull, Jane A.

    This report describes how a Library Services and Construction Act (LSCA) Title VI Library Literacy Program grant was used to improve the literacy and coping skills of illiterate and functionally illiterate inmates incarcerated at the Mississippi State Penitentiary. A second objective of this literacy program was to produce an annotated…

  10. Skills Conversion Project: Chapter 6, Forest Operations and Wood Products. Final Report.

    ERIC Educational Resources Information Center

    National Society of Professional Engineers, Washington, DC.

    A study of the forest operations and wood products industries was conducted in Atlanta and Seattle by the National Society of Professional Engineers. Included among these industries are tree development, crop and land management, logging, material handling transportation, cutting, peeling, assembly, pulp and paper, mobile homes, construction,…

  11. The Mushroom Place. Part III.

    ERIC Educational Resources Information Center

    Schlichter, Carol

    1978-01-01

    The final installment of a series of articles on the "Mushroom Place" learning center program, which involves creative thinking activities for young, gifted students, describes "Doing It the Hard Way," a performance task which involves the actual construction of objects from a selected set of materials in the absence of the usual project tools.…

  12. Construction and Application of a Terahertz Scanning Near-Field Microscope for Study of Correlated Electron Materials at Cryogenic Temperatures and Nanometer Length Scales

    NASA Astrophysics Data System (ADS)

    Stinson, Harry Theodore, III

    This dissertation describes the design and construction of the world's first cryogenic apertureless near-field microscope designed for terahertz sources and detectors. I first provide motivation for the creation of this instrument in the context of spectroscopy of correlated electron materials, and background information on the two techniques that the instrument combines, scanning near-field optical microscopy and terahertz time-domain spectroscopy. I then detail key components of the instrument design, including proof-of-principle results obtained at room and cryogenic temperatures. Following this, I discuss an imaging experiment performed with this instrument on vanadium dioxide, an insulator-metal transition material, which sheds new light on the nature of the phase transition and provides support for a new model Hamiltonian for the system. Finally, I discuss a theoretical proposal for the study of cuprate superconductors using this instrument.

  13. Nature-Inspired Structural Materials for Flexible Electronic Devices.

    PubMed

    Liu, Yaqing; He, Ke; Chen, Geng; Leow, Wan Ru; Chen, Xiaodong

    2017-10-25

    Exciting advancements have been made in the field of flexible electronic devices in the last two decades and will certainly lead to a revolution in peoples' lives in the future. However, because of the poor sustainability of the active materials in complex stress environments, new requirements have been adopted for the construction of flexible devices. Thus, hierarchical architectures in natural materials, which have developed various environment-adapted structures and materials through natural selection, can serve as guides to solve the limitations of materials and engineering techniques. This review covers the smart designs of structural materials inspired by natural materials and their utility in the construction of flexible devices. First, we summarize structural materials that accommodate mechanical deformations, which is the fundamental requirement for flexible devices to work properly in complex environments. Second, we discuss the functionalities of flexible devices induced by nature-inspired structural materials, including mechanical sensing, energy harvesting, physically interacting, and so on. Finally, we provide a perspective on newly developed structural materials and their potential applications in future flexible devices, as well as frontier strategies for biomimetic functions. These analyses and summaries are valuable for a systematic understanding of structural materials in electronic devices and will serve as inspirations for smart designs in flexible electronics.

  14. Caracterizacion y optimizacion electroquimica de dispositivos electrocromicos duales basados en polimeros conductores

    NASA Astrophysics Data System (ADS)

    Padilla Martinez, Javier

    The aim of this thesis is to emphasize the existing relations between electrochemical processes, or electrochemical magnitudes, and colour changes. The work is focused on two aspects: individual spectroelectrochemical characterization of the constituent materials followed by an electrochemical and optical study of the performance of the dual system constructed with those materials. The objective is the optimization of both electrochemical and optical processes in dual conducting polymer systems, obtaining experimental methodologies able to characterize, predict, and finally design optimal dual electrochromic devices. The first part of the study is focused on the development of the proper methodology to obtain an optical characterization of any electrochromic material as a function of its electrochemical properties. Materials used were poly((3,4-ethylenedioxy)thiophene) (PEDOT) and poly-(3,6-bis(2-(3,4-ethylenedioxy)thienyl)-N-methylcarbazole) (PBEDOT-NMCz). PEDOT films are coloured under reduction, while PBEDOT-NMCz are coloured under oxidation, showing complementary colouration, and so they can be used to construct a dual electrochromic device. Based on the obtained experimental results, a theoretical study was undertaken to establish the optical responses of a system comprising several electrochromic layers. The theoretically obtained relations were experimentally proved. Relations obtained allow the prediction of the maximum contrast configuration for a dual system, as a function of the individual electrochemical properties of each constituent material. The system studied was PEDOT/PBEDOT-NMCz. The third chapter deals with the proposal and development of a new experimental methodology able to register the individual oxidation states of each electrode during operation of a dual device, obtaining then direct information about device performance. This methodology allows the study of the influence of different physical and chemical variables, like ratio of redox charge between both constituent films, applied potential to the device and initial oxidation state of the constituent polymer films, on the device performance. The final objective of this work is the construction of electrochromic devices that can be use in real applications out of research or academic contexts. It is necessary then, for safety purposes, to use solid electrolytes in the cell. For final applications it is also required to construct devices of appropriate dimensions. In the fourth chapter, the construction and study of large dimensions and solid state devices for the system PEDOT/PBEDOT-NMCz was carried out. The information obtained in previous sections was used to determine maximum contrast combinations. Problems related to electrodeposition of conducting polymers on large surfaces (around 30 cm2) are discussed, together with the optimization of switching speeds when a solid electrolyte is used. Finally the ability to tune colour states and retain them in the absence of an external potential applied was studied and discussed. The last section deals with the study of two new cathodically colouring polymers, poly(3-(Biphenyl-4-ylmethoxymethyl)-3,4-dihydro-2H-thieno(3,4-b)-(1,2)dioxepine) (BPMOM-ProDOT) and poly-dibenzylProDOT (PDiBz-ProDOT), which have been reported to show larger contrasts than PEDOT. For this reason, dual cells were constructed and checked by combination of these two polymers with PBEDOT-NMCz. The methodology previously developed and used to characterize PEDOT and PBEDOT-NMCz was applied to these polymers. The developed theoretical equations were used to determine the maximum contrast for both systems. Finally, the use of standard optical magnitudes as photopic values is emphasized. Photopic values are standardized by the Commission Internationale de l'Eclairage (CIE), and correspond to real sensations perceived by the human eye, whose sensitivity is different for each wavelength. In this sense the use of photopic values, instead of values corresponding to a single wavelength, is encouraged. (Abstract shortened by UMI.)

  15. Numerical Analysis of a Class of THM Coupled Model for Porous Materials

    NASA Astrophysics Data System (ADS)

    Liu, Tangwei; Zhou, Jingying; Lu, Hongzhi

    2018-01-01

    We consider the coupled models of the Thermo-hydro-mechanical (THM) problem for porous materials which arises in many engineering applications. Firstly, mathematical models of the THM coupled problem for porous materials were discussed. Secondly, for different cases, some numerical difference schemes of coupled model were constructed, respectively. Finally, aassuming that the original water vapour effect is neglectable and that the volume fraction of liquid phase and the solid phase are constants, the nonlinear equations can be reduced to linear equations. The discrete equations corresponding to the linear equations were solved by the Arnodli method.

  16. The materials used in bone tissue engineering

    NASA Astrophysics Data System (ADS)

    Tereshchenko, V. P.; Kirilova, I. A.; Sadovoy, M. A.; Larionov, P. M.

    2015-11-01

    Bone tissue engineering looking for an alternative solution to the problem of skeletal injuries. The method is based on the creation of tissue engineered bone tissue equivalent with stem cells, osteogenic factors, and scaffolds - the carriers of these cells. For production of tissue engineered bone equivalent is advisable to create scaffolds similar in composition to natural extracellular matrix of the bone. This will provide optimal conditions for the cells, and produce favorable physico-mechanical properties of the final construction. This review article gives an analysis of the most promising materials for the manufacture of cell scaffolds. Biodegradable synthetic polymers are the basis for the scaffold, but it alone cannot provide adequate physical and mechanical properties of the construction, and favorable conditions for the cells. Addition of natural polymers improves the strength characteristics and bioactivity of constructions. Of the inorganic compounds, to create cell scaffolds the most widely used calcium phosphates, which give the structure adequate stiffness and significantly increase its osteoinductive capacity. Signaling molecules do not affect the physico-mechanical properties of the scaffold, but beneficial effect is on the processes of adhesion, proliferation and differentiation of cells. Biodegradation of the materials will help to fulfill the main task of bone tissue engineering - the ability to replace synthetic construct by natural tissues that will restore the original anatomical integrity of the bone.

  17. Overview and status of the Giant Magellan Telescope Project

    NASA Astrophysics Data System (ADS)

    McCarthy, Patrick J.; Fanson, James; Bernstein, Rebecca; Ashby, David; Bigelow, Bruce; Boyadjian, Nune; Bouchez, Antonin; Chauvin, Eric; Donoso, Eduardo; Filgueira, Jose; Goodrich, Robert; Groark, Frank; Jacoby, George; Pearce, Eric

    2016-08-01

    The Giant Magellan Telescope Project is in the construction phase. Production of the primary mirror segments is underway with four of the seven required 8.4m mirrors at various stages of completion and materials purchased for segments five and six. Development of the infrastructure at the GMT site at Las Campanas is nearing completion. Power, water, and data connections sufficient to support the construction of the telescope and enclosure are in place and roads to the summit have been widened and graded to support transportation of large and heavy loads. Construction pads for the support buildings have been graded and the construction residence is being installed. A small number of issues need to be resolved before the final design of the telescope structure and enclosure can proceed and the GMT team is collecting the required inputs to the decision making process. Prototyping activities targeted at the active and adaptive optics systems are allowing us to finalize designs before large scale production of components begins. Our technically driven schedule calls for the telescope to be assembled on site in 2022 and to be ready to receive a subset of the primary and secondary mirror optics late in the year. The end date for the project is coupled to the delivery of the final primary mirror segments and the adaptive secondary mirrors that support adaptive optics operations.

  18. Utilization of construction and agricultural waste in Malaysia for development of Green Concrete: A Review

    NASA Astrophysics Data System (ADS)

    Tambichik, M. A.; Mohamad, N.; Samad, A. A. A.; Bosro, M. Z. M.; Iman, M. A.

    2018-04-01

    Green Concrete (GC) is defined as a concrete that utilize a waste material for at least one of its component. The production of GC has been increasing due to the drawback of conventional concrete that create many environmental problems. In Malaysia, the amount of waste generates from agricultural and construction industries were increasing every year. Hence, one of the solutions to reduce the impact of conventional concrete and limited landfill spaces due to excessive waste is by utilizing it in concrete. This paper reviews the possible use of construction waste (Recycle Concrete Aggregate) and agricultural waste (Palm Oil Fuel Ash, Rice Husk Ash and Palm Oil Fibre) as partial replacement for the basic material in a concrete to produce an innovative Green Concrete. The optimum replacement level for each type of waste was also been review. Green Concrete also has the potential to reduce environmental pollution and solve the depletion of natural sources. The result from this review shows that the addition of agricultural waste or construction waste in concrete indicate positive and satisfactory strength when compared to normal concrete. Finally, a mass production of Green Concrete can fulfil the Construction Industry Transformation Plan (CITP) 2016-2020 made by CIDB that emphasizes on a construction system which is environmentally sustainable.

  19. Manufacturing and Machining Challenges of Hybrid Aluminium Metal Matix Composites

    NASA Astrophysics Data System (ADS)

    Baburaja, Kammuluri; Sainadh Teja, S.; Karthik Sri, D.; Kuldeep, J.; Gowtham, V.

    2017-08-01

    Manufacturing which involves material removal processes or material addition processes or material transformation processes. One or all the processes to obtain the final desired properties for a material with desired shape which meets the required precision and accuracy values for the expected service life of a material in working conditions. Researchers found the utility of aluminium to be the second largest after steel. Aluminium and its metal matrix composite possess wide applications in various applications in aerospace industry, automobile industry, Constructions and even in kitchen utensils. Hybrid Al-MMCconsist of two different materials, and one will be from organic origin along with the base material. In this paper an attempt is made to bring out the importance of utilization of aluminium and the challenges concerned in manufacturing and machining of hybrid aluminium MMC.

  20. Underground waste barrier structure

    DOEpatents

    Saha, Anuj J.; Grant, David C.

    1988-01-01

    Disclosed is an underground waste barrier structure that consists of waste material, a first container formed of activated carbonaceous material enclosing the waste material, a second container formed of zeolite enclosing the first container, and clay covering the second container. The underground waste barrier structure is constructed by forming a recessed area within the earth, lining the recessed area with a layer of clay, lining the clay with a layer of zeolite, lining the zeolite with a layer of activated carbonaceous material, placing the waste material within the lined recessed area, forming a ceiling over the waste material of a layer of activated carbonaceous material, a layer of zeolite, and a layer of clay, the layers in the ceiling cojoining with the respective layers forming the walls of the structure, and finally, covering the ceiling with earth.

  1. The Chemistry of Ultra-Radiopure Materials

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Miley, Harry S.; Aalseth, Craig E.; Day, Anthony R.

    Ultra-pure materials are needed for the construction of the next generation of ultra-low level radiation detectors. These detectors are used for environmental research as well as rare nuclear decay experiments, e.g. probing the effective mass and character of the neutrino. Unfortunately, radioactive isotopes are found in most construction materials, either primordial isotopes, activation/spallation products from cosmic-ray exposure, or surface deposition of dust or radon progeny. Copper is an ideal candidate material for these applications. High-purity copper is commercially available and, when even greater radiopurity is needed, additional electrochemical purification can be combined with the final construction step, resulting in “electroformed”more » copper of extreme purity. Copper also offers desirable thermal, mechanical, and electrical properties. To bridge the gap between commercially-available high purity copper and the most stringent requirements of next-generation low-background experiments, a method of additional chemical purification is being developed based on well-known copper electrochemistry. This method is complemented with the co-development of surface cleaning techniques and more sensitive assay for both surface and bulk contamination. Developments in the electroplating of copper, surface cleaning, assay of U and Th in the bulk copper, and residual surface contamination will be discussed relative to goals of less than 1 microBq/kg Th.« less

  2. Timber - Material of the Future - Examples of Small Wooden Architectural Structures

    NASA Astrophysics Data System (ADS)

    Żmijewki, Tomasz; Wojtowicz-Jankowska, Dorota

    2017-10-01

    The aim of this article is to present various types of wood-based products, classified as engineered timber, while specifying the implications of their structural properties for their forms. Timber is used as a construction material due to its fire resistance, good structural characteristics and insulating properties. The advent of new technologies of wood processing and wood-based materials production has converted timber into a high-tech material, thus encouraging the architects to consider it ever more often in their projects. As wooden technologies overcome constraints, timber begins to compete with steel and concrete. The design characteristics of new wood-based products allow wooden structures to be higher, have larger spans, and more diverse forms than ever. Wood-based materials include materials made of solid wood, veneers, strand, and wood which, due to its inferior quality, would otherwise be unfit for constructions. Elements and layers of these products are glued using different kinds of strong and water-resistant adhesives. The article presents the history of development of new wood technologies, discussing increasingly popular wood-based materials such as glued laminated timber, cross-laminated timber, or structural composite lumber. The paper analyses their technical and fire-resistance properties, and points to ecological aspect, as factors contributing to the growing popularity of these materials. Finally, the timber’s characteristics are contrasted with those of steel and concrete. The article lists examples of wooden objects representing the so-called small architecture structures from across Europe. They illustrate the potential, the uniqueness and the versatility that wood-based materials offer for constructors and architects. All these features form sufficient grounds for stating that timber truly is a construction material of the 21st century.

  3. Analysis of a new composite material for watercraft manufacturing

    NASA Astrophysics Data System (ADS)

    Wahrhaftig, Alexandre; Ribeiro, Henrique; Nascimento, Ademar; Filho, Milton

    2016-09-01

    In this paper, we investigate the properties of an alternative material for use in marine engineering, namely a rigid and light sandwich-structured composite made of expanded polystyrene and fiberglass. Not only does this material have an improved section modulus, but it is also inexpensive, light, easy to manipulate, and commercially available in various sizes. Using a computer program based on the finite element method, we calculated the hogging and sagging stresses and strains acting on a prismatic boat model composed of this material, and determined the minimum sizes and maximum permissible stresses to avoid deformation. Finally, we calculated the structural weight of the resulting vessel for comparison with another structure of comparable dimensions constructed from the commonly used core material Divinycell.

  4. Study on the quality of FRP fishing vessel based on improved Fishbone Chart

    NASA Astrophysics Data System (ADS)

    Sui, J. H.; Yu, Y. F.; Du, Q. F.; Jiang, D. W.

    2018-01-01

    The construction quality of FRP fishing vessels influences their production, use and industry development. In order to explore the factors that affect the construction quality of FRP fishing vessels, key factors affecting the construction quality of FRP fishing vessels are determined based on the quality problems of FRP fishing vessels constructed. The improved Fishbone Chart is used to analyze the eight factors of “human, machine, material, process, environment, inspection, design and information”. Taking the factors that affect the construction quality of FRP fishing vessels as the central target, the eight influencing factors were condensed into five aspects and a composite Fishbone Chart is drawn. The Fishbone Chart is used as the basic model, the influencing factors are sorted, screened and discriminated, and the system model convenient for construction site management and control is established. Finally, the causes of poor construction of FRP fishing vessels are analyzed and discussed, and relevant suggestions are put forward.

  5. Reverse logistics in the construction industry.

    PubMed

    Hosseini, M Reza; Rameezdeen, Raufdeen; Chileshe, Nicholas; Lehmann, Steffen

    2015-06-01

    Reverse logistics in construction refers to the movement of products and materials from salvaged buildings to a new construction site. While there is a plethora of studies looking at various aspects of the reverse logistics chain, there is no systematic review of literature on this important subject as applied to the construction industry. Therefore, the objective of this study is to integrate the fragmented body of knowledge on reverse logistics in construction, with the aim of promoting the concept among industry stakeholders and the wider construction community. Through a qualitative meta-analysis, the study synthesises the findings of previous studies and presents some actions needed by industry stakeholders to promote this concept within the real-life context. First, the trend of research and terminology related with reverse logistics is introduced. Second, it unearths the main advantages and barriers of reverse logistics in construction while providing some suggestions to harness the advantages and mitigate these barriers. Finally, it provides a future research direction based on the review. © The Author(s) 2015.

  6. 75 FR 5375 - Hazardous Material; Miscellaneous Packaging Amendments

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-02

    ...In this final rule, PHMSA is amending packaging requirements in the Hazardous Materials Regulations to enhance compliance flexibility, improve clarity, and reduce regulatory burdens. Specifically, we are revising several packaging related definitions; adding provisions to allow more flexibility when preparing and transmitting closure instructions, including conditions under which closure instructions may be transmitted electronically; adding a requirement for shippers to retain packaging closure instructions; incorporating new language that will allow for a practicable means of stenciling the ``UN'' symbol on packagings; and clarifying a requirement to document the methodology used when determining whether a change in packaging configuration requires retesting as a new design or may be considered a variation of a previously tested design. This final rule also incorporates requirements for construction, maintenance, and use of Large Packagings.

  7. Study of technology of pile foundation construction of no.5 main pier of Shoujiang bridge in Wenchuan County

    NASA Astrophysics Data System (ADS)

    Huang, Xianbin; Liu, Chenyang; Chen, Chunyang; Wangren, Yahong; Xu, Jialin; Xian, Jin

    2018-03-01

    The group of pile foundation of no.5 pier in Shoujiang Bridge needs to overcome the big load of large span continuous steel structure. The length of single pile foundation is 77m and the diameter of single pile foundation is 250cm. It not only faces the flood in the upstream of Shoujiang river, the construction obstacles during summer rain period, but also the reservoir clearance activity of Zipingpu reservoir and the high water level in winter and other water level fluctuation that have huge impact on platform of pile foundation construction. This article introduces the preparation in aspect of personnel, material, equipment and so on of pile foundation construction, and also conduct intensive research on leveling the field, assaying pile location, the embedment of the steel casing, installing the drill, mixing mud, drilling, final hole inspection and clearance, steel cage construction, perfusing concrete under water.

  8. International Space Station (ISS)

    NASA Image and Video Library

    2007-08-01

    As the construction continued on the International Space Station (ISS), STS-118 Astronaut Dave Williams, representing the Canadian Space Agency, participated in the fourth and final session of Extra Vehicular Activity (EVA). During the 5 hour space walk, Williams and Expedition 15 engineer Clay Anderson (out of frame) installed the External Wireless Instrumentation System Antenna, attached a stand for the shuttle robotic arm extension boom, and retrieved the two Materials International Space Station Experiments (MISSE) for return to Earth. MISSE collects information on how different materials weather in the environment of space.

  9. STS-118 Astronaut Williams and Expedition 15 Engineer Anderson Perform EVA

    NASA Technical Reports Server (NTRS)

    2007-01-01

    As the construction continued on the International Space Station (ISS), STS-118 Astronaut Dave Williams, representing the Canadian Space Agency, participated in the fourth and final session of Extra Vehicular Activity (EVA). During the 5 hour space walk, Williams and Expedition 15 engineer Clay Anderson (out of frame) installed the External Wireless Instrumentation System Antenna, attached a stand for the shuttle robotic arm extension boom, and retrieved the two Materials International Space Station Experiments (MISSE) for return to Earth. MISSE collects information on how different materials weather in the environment of space.

  10. 48 CFR 532.905-70 - Final payment-construction and building service contracts.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 4 2012-10-01 2012-10-01 false Final payment-construction...-70 Final payment—construction and building service contracts. The following procedures apply to construction and building service contracts: (a) The Government shall pay the final amount due the Contractor...

  11. 48 CFR 532.905-70 - Final payment-construction and building service contracts.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 4 2014-10-01 2014-10-01 false Final payment-construction...-70 Final payment—construction and building service contracts. The following procedures apply to construction and building service contracts: (a) The Government shall pay the final amount due the Contractor...

  12. 48 CFR 532.905-70 - Final payment-construction and building service contracts.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 4 2013-10-01 2013-10-01 false Final payment-construction...-70 Final payment—construction and building service contracts. The following procedures apply to construction and building service contracts: (a) The Government shall pay the final amount due the Contractor...

  13. Raman Spectrometer for Surface Identification of Minerals and Organic Compounds on Silicate Planets and Small Solar-System Bodies

    NASA Technical Reports Server (NTRS)

    Haskin, Larry A.

    2000-01-01

    This summary is the final report of work on two-year grant. Our objectives for this project were (1) to demonstrate that Raman spectroscopy is an excellent method for determining mineralogy on the surface of the Moon, Mars, and other planetary bodies; (2) to construct a prototype of a small Raman spectrometer of the kind we suggest could be used on a lander or rover; and (3) to test the ability of that spectrometer to identify minerals and quantify mineral proportions in lunar materials and complex Martian analog materials, and to identify organic matter in planetary surface materials, all under roughly simulated field conditions. These goals have been met. The principal accomplishments of this PIDDP project have been the following: selection for flight; construction of a breadboard Raman probe; throughput confirmation of the breadboard Raman probe; selection of a laser; a breadboard spectrograph based on our PIDDP design; and overall result.

  14. Principles and Applications of Ultrasonic-Based Nondestructive Methods for Self-Healing in Cementitious Materials

    PubMed Central

    Ahn, Eunjong; Kim, Hyunjun; Sim, Sung-Han; Shin, Sung Woo; Shin, Myoungsu

    2017-01-01

    Recently, self-healing technologies have emerged as a promising approach to extend the service life of social infrastructure in the field of concrete construction. However, current evaluations of the self-healing technologies developed for cementitious materials are mostly limited to lab-scale experiments to inspect changes in surface crack width (by optical microscopy) and permeability. Furthermore, there is a universal lack of unified test methods to assess the effectiveness of self-healing technologies. Particularly, with respect to the self-healing of concrete applied in actual construction, nondestructive test methods are required to avoid interrupting the use of the structures under evaluation. This paper presents a review of all existing research on the principles of ultrasonic test methods and case studies pertaining to self-healing concrete. The main objective of the study is to examine the applicability and limitation of various ultrasonic test methods in assessing the self-healing performance. Finally, future directions on the development of reliable assessment methods for self-healing cementitious materials are suggested. PMID:28772640

  15. The materials used in bone tissue engineering

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tereshchenko, V. P., E-mail: tervp@ngs.ru; Kirilova, I. A.; Sadovoy, M. A.

    Bone tissue engineering looking for an alternative solution to the problem of skeletal injuries. The method is based on the creation of tissue engineered bone tissue equivalent with stem cells, osteogenic factors, and scaffolds - the carriers of these cells. For production of tissue engineered bone equivalent is advisable to create scaffolds similar in composition to natural extracellular matrix of the bone. This will provide optimal conditions for the cells, and produce favorable physico-mechanical properties of the final construction. This review article gives an analysis of the most promising materials for the manufacture of cell scaffolds. Biodegradable synthetic polymers aremore » the basis for the scaffold, but it alone cannot provide adequate physical and mechanical properties of the construction, and favorable conditions for the cells. Addition of natural polymers improves the strength characteristics and bioactivity of constructions. Of the inorganic compounds, to create cell scaffolds the most widely used calcium phosphates, which give the structure adequate stiffness and significantly increase its osteoinductive capacity. Signaling molecules do not affect the physico-mechanical properties of the scaffold, but beneficial effect is on the processes of adhesion, proliferation and differentiation of cells. Biodegradation of the materials will help to fulfill the main task of bone tissue engineering - the ability to replace synthetic construct by natural tissues that will restore the original anatomical integrity of the bone.« less

  16. Multifunctional wall coating combining photocatalysis, self-cleaning and latent heat storage

    NASA Astrophysics Data System (ADS)

    Lucas, S. S.; Barroso de Aguiar, J. L.

    2018-02-01

    Mortars, one of the most common construction materials, have not received any substantial modification for many decades. This has changed in recent years; new compositions are now being developed, with new properties, using nano-additives, fibres and capsules. In this work, surfaces with new and innovative functionalities that promote energy savings and improve air quality have been developed and studied. Incorporation of phase change materials (PCM) and titanium dioxide (TiO2) nanoparticles in construction products is currently under study by different research groups. However, these studies only address their incorporation separately. Adding new additives into the mortar’s matrix can be complex—due to microstructural modifications that will influence both fresh and hardened state properties. Moving from a single additive to multiple additions, as in this study, increases the system’s complexity. Only with a good understanding of the microstructural properties, it is possible to add multiple additives (including nano and microparticles) to mortars, without damaging its final quality. This work demonstrates that a higher additive content is not always a guarantee of better results; lower additions can often provide a better compromise between performance and final mechanical properties. The results presented in this paper confirmed this and show that combining PCM microcapsules and TiO2 nanoparticles open a new path in the development of mortars with multiple functionalities. In this study, a new material with depolluting, self-cleaning and heat storage was created. For the development of new and innovative mortars, a proper balance of multiple additives, supported by the study of microstructural changes, can lead to an optimization of the compositions, ensuring that the mortar’s final properties are not affected.

  17. Solar Concentration for Electricity and Cooking

    NASA Astrophysics Data System (ADS)

    Kim, Mike; Fourt, Connor; Schwartz, Pete; Lee, Michael; Frostholm, Taylor; Fernandes, Josh; Tower, Jared

    2012-11-01

    Over 8000 Schefflers exist worldwide, mostly in Africa and Asia. Having constructed the first Scheffler reflector in North America 2 years ago, the next goal was to make it less expensive. The original model took 4 students 2 months and about 1000. In order to lower the cost and construction time the design was minimized, less expensive materials were used, and the construction process was automated. The original complex frame took 1000 people-hours and it was minimized to a day. Instead of using aluminum for the reflective dish, we turned to using aluminized Mylar, which cut the cost by over 90%. A thermal storage unit was added to extend cooking time well into the evening. Finally, a concentrated solar module of High Efficiency Photo Voltaics (HEPV) is to be placed at the focus of the concentrator to generate electricity and water as a byproduct. The final cost is estimated to be about 200 (0.10 per thermal watt) including the HEPV, an 80% cost reduction. Such technology is practical in the U.S. as well as developing nations.

  18. Evaluation of Water Repellency in Petroleum Drilling Cuttings Treated by Thermal Desorption: Implications for Use in Construction and Agriculture

    NASA Astrophysics Data System (ADS)

    Domínguez-Rodríguez, Verónica I.; Guzmán-Osorio, Francisco J.; Adams Schroeder, Randy H.; Bautista-Margulis, Raúl G.

    2010-05-01

    Thermal desorption is one of many methods used for the remediation of hydrocarbon contaminated soils and similar materials. It has several advantages over competing technologies, especially with respect to treatment times. While the biological treatment of contaminated soils may take several months depending principally on the type of hydrocarbons and starting concentration, thermal desorption typically takes less than one month, depending on the treatment capacities of the equipment involved, and the volume of material requiring treatment. In the petroleum producing region of southeastern Mexico, this has been one of the principal methods used for the treatment of drilling cuttings, due mostly to the short time required. As with most remediation projects, as well as in the treatment of exploration and production (E&P) wastes, the criteria used to consider the remediation finalized is the concentration of hydrocarbons in the treated material. This is based on the supposition that at some (relatively low) hydrocarbon concentration, the toxicological affects are reduced to acceptable levels. However, little attention has been paid to the physical-chemical properties of supposedly treated material, which may suffer from water repellency, especially in thermal treatment methods. This could greatly reduce the options for final use of treated materials, especially to support plant growth. Conversely, there may be some construction uses of treated material in which some water repellence could be beneficial (caps for land fills, for example). Considering the relevance of the physical-chemical impacts of petroleum on soil and similar materials, we felt it was important to evaluate the efficiency of the principal method used to treat E&P wastes in Mexico (thermal desporption) based on these factors. In this study different operating conditions (temperature and residence time) of a sub-pilot scale thermal desorption unit were evaluated with respect not only to reduction in hydrocarbon concentration, but also based on water repellency. To our knowledge this is the first study of this type. Water repellency severity was measured in petroleum drilling cuttings which had been treated by thermal desorption to reduce the concentration of total petroleum hydrocarbons (TPHs). The initial TPH concentration in the untreated material was 16850mg/Kg (dry). The prototype batch rotary oven used in this study was operated at 25 rpm, at three temperatures and three treatment times: at 150, 200, and 300°C, for 10, 15, and 20 minutes. Four of the nine treatments complied with the Mexican environmental norm (TPH less than 3000 mg/Kg), these being: at 200°C for 20 minutes and at 300°C for 10, 15 and 20 minutes. The treatments at 150°C resulted in a TPH reduction insufficient to comply with Mexican norm, and also resulted in high MED values (3,46 - 3,67). At 200°C, the decrease in repellency was directly proportional to the treatment time (r=-0,950), with a final value of MED=2,61 after 20 minutes. At 300°C, an increase in water repellency was observed to be directly proportional to the treatment time (r=0,9997), with a final value of MED=3,73 (severe repellence) after 20 minutes. This may be due to the partial combustion (rather than only desorption) of hydrocarbons at this temperature, and their deposition on soil surfaces. Based on these observations, operating conditions of 200°C for 20 minutes are recommended to achieve effective thermal desorption while reducing water repellency in the treated material. If a final material with more severe water repellency is desired for use in construction, a higher operation temperature is required (300°C) for at least 15-20 minutes.

  19. Construction risk assessment of deep foundation pit in metro station based on G-COWA method

    NASA Astrophysics Data System (ADS)

    You, Weibao; Wang, Jianbo; Zhang, Wei; Liu, Fangmeng; Yang, Diying

    2018-05-01

    In order to get an accurate understanding of the construction safety of deep foundation pit in metro station and reduce the probability and loss of risk occurrence, a risk assessment method based on G-COWA is proposed. Firstly, relying on the specific engineering examples and the construction characteristics of deep foundation pit, an evaluation index system based on the five factors of “human, management, technology, material and environment” is established. Secondly, the C-OWA operator is introduced to realize the evaluation index empowerment and weaken the negative influence of expert subjective preference. The gray cluster analysis and fuzzy comprehensive evaluation method are combined to construct the construction risk assessment model of deep foundation pit, which can effectively solve the uncertainties. Finally, the model is applied to the actual project of deep foundation pit of Qingdao Metro North Station, determine its construction risk rating is “medium”, evaluate the model is feasible and reasonable. And then corresponding control measures are put forward and useful reference are provided.

  20. Viability of Bioprinted Cellular Constructs Using a Three Dispenser Cartesian Printer.

    PubMed

    Dennis, Sarah Grace; Trusk, Thomas; Richards, Dylan; Jia, Jia; Tan, Yu; Mei, Ying; Fann, Stephen; Markwald, Roger; Yost, Michael

    2015-09-22

    Tissue engineering has centralized its focus on the construction of replacements for non-functional or damaged tissue. The utilization of three-dimensional bioprinting in tissue engineering has generated new methods for the printing of cells and matrix to fabricate biomimetic tissue constructs. The solid freeform fabrication (SFF) method developed for three-dimensional bioprinting uses an additive manufacturing approach by depositing droplets of cells and hydrogels in a layer-by-layer fashion. Bioprinting fabrication is dependent on the specific placement of biological materials into three-dimensional architectures, and the printed constructs should closely mimic the complex organization of cells and extracellular matrices in native tissue. This paper highlights the use of the Palmetto Printer, a Cartesian bioprinter, as well as the process of producing spatially organized, viable constructs while simultaneously allowing control of environmental factors. This methodology utilizes computer-aided design and computer-aided manufacturing to produce these specific and complex geometries. Finally, this approach allows for the reproducible production of fabricated constructs optimized by controllable printing parameters.

  1. A One-Piece Lunar Regolith Bag Garage Prototype

    NASA Technical Reports Server (NTRS)

    Smithers, G. A.; Nehls, M. K.; Hovater, M. A.; Evans, S. W.; Miller, J. S.; Broughton, R. M., Jr.; Beale, D.; Kilinc-Balci, F.

    2007-01-01

    Shelter structures on the moon, even in early phases of exploration, should incorporate lunar materials as much as possible. This Technical Memorandum details the design and construction of a prototype for a one-piece regolith bag unpressurized garage concept and a materials testing program to investigate six candidate fabrics to learn how they might perform in the lunar environment. The conceptualization was that a lightweight fabric form be launched from Earth and landed on the lunar surface to be robotically filled with raw lunar regolith. Regolith bag fabric candidates included: Vectran(TM), Nextel(TM), Gore PTFE Fabric(TM), Zylon(TM), Twaron(TM), and Nomex(TM). Tensile (including post radiation exposure), fold, abrasion, and hypervelocity impact testing were performed under ambient conditions, and also performed under cold and elevated temperatures. In some cases, Johnson Space Center lunar simulant (JSC-1) was used in conjunction with testing. A series of preliminary structures was constructed during final prototype design based on the principles of the classic masonry arch. The prototype was constructed of Kevlar(TM) and filled with vermiculite. The structure is free-standing, but has not yet been load tested. Future plans would be to construct higher fidelity prototypes and to conduct appropriate tests of the structure.

  2. Harlan County Public Library, Final Performance Report for Library Services and Construction Act (LSCA) Title VI, Library Literacy Program.

    ERIC Educational Resources Information Center

    Warren, Carol E.

    The Harlan County Public Library Literacy Project (Kentucky) provided rural-oriented, basic literacy, and oral history programs to a community of 100,000-200,000. The goal of the project was to produce six booklets about local people and issues, to be used as literacy materials in programs with Appalachian students. Students wanted to produce…

  3. 77 FR 12182 - Safety Standard for Portable Bed Rails: Final Rule

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-29

    ... of ASTM F2085- 10a, comply with the following: (i) 1.4.1 Foam and inflatable bed rails need meet only...--portable bed rail constructed primarily of nonrigid materials such as fabric or foam. 3.1.11 inflatable bed..., inflatable bed rail, are terms that are now incorporated as non-rigid bed rail under new section 3.1.12 in...

  4. Environmental and Geotechnical Assessment of the Steel Slags as a Material for Road Structure.

    PubMed

    Sas, Wojciech; Głuchowski, Andrzej; Radziemska, Maja; Dzięcioł, Justyna; Szymański, Alojzy

    2015-07-30

    Slags are the final solid wastes from the steel industry. Their production from waste and associated materials is a proper implementation of the basic objectives and principles of the waste management. This study aims to investigate the chemical and selected significant geotechnical parameters of steel slag as the alternative materials used in road construction. These investigations are strongly desired for successful application in engineering. Young's modules E , and resilient modules M r showed that their values corresponding with requirements for subbase (principal or auxiliary) and riding surface as well. Tested mechanical properties were conducted in soaked and un-soaked (optimal moisture content) conditions. The designated high content of chromium and zinc are strongly associated with the internal crystal structure of steel slag. The results do not lead to threats when they are applied in roads' structures. Mechanical characterization was obtained by performing California bearing ratio (CBR) tests for steel slag in fixed compaction and moisture content conditions. Moreover, cyclic loading of steel slag was conducted with the application of cyclic California bearing ratio (cCBR) apparatus to characterization of this material as a controlled low-strength material. Finally, field studies that consist of static load plate VSS tests were presented.

  5. Master plot analysis of microcracking in graphite/epoxy and graphite/PEEK laminates

    NASA Technical Reports Server (NTRS)

    Nairn, John A.; Hu, Shoufeng; Bark, Jong Song

    1993-01-01

    We used a variational stress analysis and an energy release rate failure criterion to construct a master plot analysis of matrix microcracking. In the master plot, the results for all laminates of a single material are predicted to fall on a single line whose slope gives the microcracking toughness of the material. Experimental results from 18 different layups of AS4/3501-6 laminates show that the master plot analysis can explain all observations. In particular, it can explain the differences between microcracking of central 90 deg plies and of free-surface 90 deg plies. Experimental results from two different AS4/PEEK laminates tested at different temperatures can be explained by a modified master plot that accounts for changes in the residual thermal stresses. Finally, we constructed similar master plot analyses for previous literature microcracking models. All microcracking theories that ignore the thickness dependence of the stresses gave poor results.

  6. Universal Fragment Descriptors for Predicting Electronic and Mechanical Properties of Inorganic Crystals

    NASA Astrophysics Data System (ADS)

    Oses, Corey; Isayev, Olexandr; Toher, Cormac; Curtarolo, Stefano; Tropsha, Alexander

    Historically, materials discovery is driven by a laborious trial-and-error process. The growth of materials databases and emerging informatics approaches finally offer the opportunity to transform this practice into data- and knowledge-driven rational design-accelerating discovery of novel materials exhibiting desired properties. By using data from the AFLOW repository for high-throughput, ab-initio calculations, we have generated Quantitative Materials Structure-Property Relationship (QMSPR) models to predict critical materials properties, including the metal/insulator classification, band gap energy, and bulk modulus. The prediction accuracy obtained with these QMSPR models approaches training data for virtually any stoichiometric inorganic crystalline material. We attribute the success and universality of these models to the construction of new materials descriptors-referred to as the universal Property-Labeled Material Fragments (PLMF). This representation affords straightforward model interpretation in terms of simple heuristic design rules that could guide rational materials design. This proof-of-concept study demonstrates the power of materials informatics to dramatically accelerate the search for new materials.

  7. Carbon Mineralization by Aqueous Precipitation for Beneficial Use of CO2 from Flue Gas

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Devenney, Martin; Gilliam, Ryan; Seeker, Randy

    2013-08-01

    The objective of this project is to demonstrate an innovative process to mineralize CO2 from flue gas directly to reactive carbonates and maximize the value and versatility of its beneficial use products. The program scope includes the design, construction, and testing of a CO2 Conversion to Material Products (CCMP) Pilot Demonstration Plant utilizing CO2 from the flue gas of a power production facility in Moss Landing, CA. This topical report covers Subphase 2a which is the design phase of pilot demonstration subsystems. Materials of construction have been selected and proven in both lab scale and prototype testing to be acceptablemore » for the reagent conditions of interest. The target application for the reactive carbonate material has been selected based upon small-scale feasibility studies and the design of a continuous fiber board production line has been completed. The electrochemical cell architecture and components have been selected based upon both lab scale and prototype testing. The appropriate quality control and diagnostic techniques have been developed and tested along with the required instrumentation and controls. Finally the demonstrate site infrastructure, NEPA categorical exclusion, and permitting is all ready for the construction and installation of the new units and upgrades.« less

  8. New conceptual design of portable bamboo bridge for emergency purposes

    NASA Astrophysics Data System (ADS)

    Musthaffa, A. A.; Nor, N. M.; Yusof, M. A.; Yuhazri, M. Y.

    2018-02-01

    Portable bridges serve as routes for troops during the military operations and the disaster relief operation. Nowadays, bamboo has been regarded as one of the alternative construction materials for building and bridge structures. This paper presents the conceptual design of the portable bridge. Several types of portable bridges and bamboo bridges are reviewed in the current work. The characteristics, capability and method of construction of each bridge are discussed. Finally, the conceptual of the portable bamboo bridge for emergency purposes is presented. The idea of producing portable bridge is proposed in the current work as it is crucial for providing route for communities affected by natural disasters.

  9. An innovative time-cost-quality tradeoff modeling of building construction project based on resource allocation.

    PubMed

    Hu, Wenfa; He, Xinhua

    2014-01-01

    The time, quality, and cost are three important but contradictive objectives in a building construction project. It is a tough challenge for project managers to optimize them since they are different parameters. This paper presents a time-cost-quality optimization model that enables managers to optimize multiobjectives. The model is from the project breakdown structure method where task resources in a construction project are divided into a series of activities and further into construction labors, materials, equipment, and administration. The resources utilized in a construction activity would eventually determine its construction time, cost, and quality, and a complex time-cost-quality trade-off model is finally generated based on correlations between construction activities. A genetic algorithm tool is applied in the model to solve the comprehensive nonlinear time-cost-quality problems. Building of a three-storey house is an example to illustrate the implementation of the model, demonstrate its advantages in optimizing trade-off of construction time, cost, and quality, and help make a winning decision in construction practices. The computational time-cost-quality curves in visual graphics from the case study prove traditional cost-time assumptions reasonable and also prove this time-cost-quality trade-off model sophisticated.

  10. A One-Piece Lunar Regolith-Bag Garage Prototype

    NASA Technical Reports Server (NTRS)

    Smithers, Gweneth A.; Nehls, Mary K.; Hovater, Mary A.; Evans, Steven W.; Miller, J. Scott; Broughton, Roy M., Jr.; Beale, David; Killinc-Balci, Fatma

    2006-01-01

    Shelter structures on the moon, even in early phases of exploration, should incorporate lunar materials as much as possible. We designed and constructed a prototype for a one-piece regolith-bag unpressurized garage concept, and, in parallel, we conducted a materials testing program to investigate six candidate fabrics to learn how they might perform in the lunar environment. In our concept, a lightweight fabric form is launched from Earth to be landed on the lunar surface and robotically filled with raw lunar regolith. In the materials testing program, regolith-bag fabric candidates included: VectranTM, NextelTM, Gore PTFE FabricTM, ZylonTM TwaronTM and NomexTM. Tensile (including post radiation exposure), fold, abrasion, and hypervelocity impact testing were performed under ambient conditions, and, within our current means, we also performed these tests under cold and elevated temperatures. In some cases, lunar simulant (JSC-1) was used in conjunction with testing. Our ambition is to continuously refine our testing to reach lunar environmental conditions to the extent possible. A series of preliminary structures were constructed during design of the final prototype. Design is based on the principles of the classic masonry arch. The prototype was constructed of KevlarTM and filled with vermiculite (fairly close to the weight of lunar regolith on the moon). The structure is free-standing, but has not yet been load tested. Our plan for the future would be to construct higher fidelty mockups with each iteration, and to conduct appropriate tests of the structure.

  11. A One-Piece Lunar Regolith-Bag Garage Prototype

    NASA Technical Reports Server (NTRS)

    Smithers, Gweneth A.; Nehls, Mary K.; Hovater, Mary A.; Evans, Steven W.; Miller, J. Scott; Broughton, Roy M.; Beale, David; Killing-Balci, Fatma

    2007-01-01

    Shelter structures on the moon, even in early phases of exploration, should incorporate lunar materials as much as possible. We designed and constructed a prototype for a one-piece regolith-bag unpressurized garage concept, and, in parallel, we conducted a materials testing program to investigate six candidate fabrics to learn how they might perform in the lunar environment. In our concept, a lightweight fabric form is launched from Earth to be landed on the lunar surface and robotically filled with raw lunar regolith. In the materials testing program, regolith-bag fabric candidates included: Vectran(TM), Nextel(TM), Gore PTFE Fabric(TM), Zylon(TM), Twaron(TM), and Nomex(TM). Tensile (including post radiation exposure), fold, abrasion, and hypervelocity impact testing were performed under ambient conditions, and, within our current means, we also performed these tests under cold and elevated temperatures. In some cases, lunar simulant (JSC-1) was used in conjunction with testing. Our ambition is to continuously refine our testing to reach lunar environmental conditions to the extent possible. A series of preliminary structures were constructed during design of the final prototype. Design is based on the principles of the classic masonry arch. The prototype was constructed of Kevlar(TM) and filled with vermiculite (fairly close to the weight of lunar regolith on the moon). The structure is free-standing, but has not yet been load tested. Our plan for the future would be to construct higher fidelity mockups with each iteration, and to conduct appropriate tests of the structure.

  12. Analysis of Air Force Wartime Contracted Construction Project Performance

    DTIC Science & Technology

    2015-03-26

    Management, Volume 140. Branconi, C. v. & Loch, C. H., 2004. Contracting for major projects: eight business levers for top management. International ...Problems X Material Supply Problems X Poor Owner Management X X Poor Contractor Management X Corruption and Bribery X The USACE survey...Kremers, et al., 2010; GAO, 2014; Thibault, 2011). The final difference, corruption and bribery , was mentioned in the USACE study as well as by Kremers

  13. Final Environmental Assessment Addressing a Proposed Airfield Drainage Improvement Project, Dobbins Air Reserve Base, Georgia

    DTIC Science & Technology

    2013-11-01

    Construction ofNew gynmasium with basketball/volleyball comt and spectator Fitness Center seating area, racquetball comts , and a resistance and free...Martin Aeronautics Material Recycling Facility: Option 1, Facility Layout. 3 August 2011. Deprutment of Defense (DOD). 2010. Memorandum from Dorothy...Selected Airport Noise Analysis Issues. August 1992. Harvard University. 2010. "Diversity Data- Atlanta-Sandy Sptings-Matietta, GA." Available online

  14. Exploiting Novel Radiation-Induced Electromagnetic Material Changes for Remote Detection and Monitoring: Final Progress Report

    DTIC Science & Technology

    2016-04-01

    research has been that the feedback amplifiers are sensitive to many controllable and some, as of yet, uncontrollable environmental factors. Many of these...shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number...41  3.2.3  Design , construction, and testing of GEN-1 feedback amplifier

  15. Structural analysis of cylindrical thrust chambers, volume 1

    NASA Technical Reports Server (NTRS)

    Armstrong, W. H.

    1979-01-01

    Life predictions of regeneratively cooled rocket thrust chambers are normally derived from classical material fatigue principles. The failures observed in experimental thrust chambers do not appear to be due entirely to material fatigue. The chamber coolant walls in the failed areas exhibit progressive bulging and thinning during cyclic firings until the wall stress finally exceeds the material rupture stress and failure occurs. A preliminary analysis of an oxygen free high conductivity (OFHC) copper cylindrical thrust chamber demonstrated that the inclusion of cumulative cyclic plastic effects enables the observed coolant wall thinout to be predicted. The thinout curve constructed from the referent analysis of 10 firing cycles was extrapolated from the tenth cycle to the 200th cycle. The preliminary OFHC copper chamber 10-cycle analysis was extended so that the extrapolated thinout curve could be established by performing cyclic analysis of deformed configurations at 100 and 200 cycles. Thus the original range of extrapolation was reduced and the thinout curve was adjusted by using calculated thinout rates at 100 and 100 cycles. An analysis of the same underformed chamber model constructed of half-hard Amzirc to study the effect of material properties on the thinout curve is included.

  16. Bioprinting Cellularized Constructs Using a Tissue-specific Hydrogel Bioink

    PubMed Central

    Skardal, Aleksander; Devarasetty, Mahesh; Kang, Hyun-Wook; Seol, Young-Joon; Forsythe, Steven D.; Bishop, Colin; Shupe, Thomas; Soker, Shay; Atala, Anthony

    2016-01-01

    Bioprinting has emerged as a versatile biofabrication approach for creating tissue engineered organ constructs. These constructs have potential use as organ replacements for implantation in patients, and also, when created on a smaller size scale as model "organoids" that can be used in in vitro systems for drug and toxicology screening. Despite development of a wide variety of bioprinting devices, application of bioprinting technology can be limited by the availability of materials that both expedite bioprinting procedures and support cell viability and function by providing tissue-specific cues. Here we describe a versatile hyaluronic acid (HA) and gelatin-based hydrogel system comprised of a multi-crosslinker, 2-stage crosslinking protocol, which can provide tissue specific biochemical signals and mimic the mechanical properties of in vivo tissues. Biochemical factors are provided by incorporating tissue-derived extracellular matrix materials, which include potent growth factors. Tissue mechanical properties are controlled combinations of PEG-based crosslinkers with varying molecular weights, geometries (linear or multi-arm), and functional groups to yield extrudable bioinks and final construct shear stiffness values over a wide range (100 Pa to 20 kPa). Using these parameters, hydrogel bioinks were used to bioprint primary liver spheroids in a liver-specific bioink to create in vitro liver constructs with high cell viability and measurable functional albumin and urea output. This methodology provides a general framework that can be adapted for future customization of hydrogels for biofabrication of a wide range of tissue construct types. PMID:27166839

  17. Bioprinting Cellularized Constructs Using a Tissue-specific Hydrogel Bioink.

    PubMed

    Skardal, Aleksander; Devarasetty, Mahesh; Kang, Hyun-Wook; Seol, Young-Joon; Forsythe, Steven D; Bishop, Colin; Shupe, Thomas; Soker, Shay; Atala, Anthony

    2016-04-21

    Bioprinting has emerged as a versatile biofabrication approach for creating tissue engineered organ constructs. These constructs have potential use as organ replacements for implantation in patients, and also, when created on a smaller size scale as model "organoids" that can be used in in vitro systems for drug and toxicology screening. Despite development of a wide variety of bioprinting devices, application of bioprinting technology can be limited by the availability of materials that both expedite bioprinting procedures and support cell viability and function by providing tissue-specific cues. Here we describe a versatile hyaluronic acid (HA) and gelatin-based hydrogel system comprised of a multi-crosslinker, 2-stage crosslinking protocol, which can provide tissue specific biochemical signals and mimic the mechanical properties of in vivo tissues. Biochemical factors are provided by incorporating tissue-derived extracellular matrix materials, which include potent growth factors. Tissue mechanical properties are controlled combinations of PEG-based crosslinkers with varying molecular weights, geometries (linear or multi-arm), and functional groups to yield extrudable bioinks and final construct shear stiffness values over a wide range (100 Pa to 20 kPa). Using these parameters, hydrogel bioinks were used to bioprint primary liver spheroids in a liver-specific bioink to create in vitro liver constructs with high cell viability and measurable functional albumin and urea output. This methodology provides a general framework that can be adapted for future customization of hydrogels for biofabrication of a wide range of tissue construct types.

  18. 77 FR 49741 - Cranes and Derricks in Construction: Demolition and Underground Construction

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-17

    ... Analysis When it issued the final cranes rule, OSHA prepared a final economic analysis (FEA) as required by... construction and cranes engaged in construction work involving demolition. The FEA for the final cranes..., found that the requirements of the rule were technologically and economically feasible. Because the FEA...

  19. The feasibility of solar reflector production from lunar materials for solar power in space

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Science Applications International Corporation (SAIC) investigated the feasibility of producing solar reflectors from indigenous lunar materials for solar power production on the moon. First, lunar construction materials and production processes were reviewed, and candidate materials for reflector production were identified. At the same time, lunar environmental conditions were reviewed for their effect on production of concentrators. Next, conceptual designs and fabrication methods were proposed and studied for production of dish concentrators and heliostats. Finally, fabrication testing was performed on small-scale models using earth analogs of lunar materials. Findings from this initial investigation indicate that production of concentrators from lunar materials may be an attractive approach for solar energy production on the moon. Further design and testing are required to determine the best techniques and approaches to optimize this concept. Four materials were identified as having high potential for solar reflector manufacture. These baseline materials were foamed glass, concrete with glass-fiber reinforcement, a glass-fiber/glass-melt composite, and an iron-glass sintered material.

  20. Application of mathematical model methods for optimization tasks in construction materials technology

    NASA Astrophysics Data System (ADS)

    Fomina, E. V.; Kozhukhova, N. I.; Sverguzova, S. V.; Fomin, A. E.

    2018-05-01

    In this paper, the regression equations method for design of construction material was studied. Regression and polynomial equations representing the correlation between the studied parameters were proposed. The logic design and software interface of the regression equations method focused on parameter optimization to provide the energy saving effect at the stage of autoclave aerated concrete design considering the replacement of traditionally used quartz sand by coal mining by-product such as argillite. The mathematical model represented by a quadric polynomial for the design of experiment was obtained using calculated and experimental data. This allowed the estimation of relationship between the composition and final properties of the aerated concrete. The surface response graphically presented in a nomogram allowed the estimation of concrete properties in response to variation of composition within the x-space. The optimal range of argillite content was obtained leading to a reduction of raw materials demand, development of target plastic strength of aerated concrete as well as a reduction of curing time before autoclave treatment. Generally, this method allows the design of autoclave aerated concrete with required performance without additional resource and time costs.

  1. Low-cost electromagnetic shielding using drywall composites: results of RFI (radio-frequency interference) testing of a shielding effectiveness. Final technical report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Williams, P.F.; Heyen, K.K.; McCormack, R.G.

    1987-10-01

    Because of developments in electronics technology, the need for electromagnetic shielding has increased. To reduce the cost of this shielding, new materials are needed. The U.S. Army Corps of Engineers, Fort Worth District (FWD), and the U.S. Army Construction Engineering Research Laboratory (USA-CERL) have developed composite materials that use standard, construction-grade, aluminum foil-backed gypsum board in combination with either a metal mesh or lead foil. Special seams for these composites were designed by U.S. Gypsum Company. USA-CERL evaluated the adequacy of each material and seam design by using radio-frequency antennas and receivers to measure its shielding effectiveness when mounted inmore » the wall of a shielded room. These evaluations showed that the composite panels met the specified requirement of 60 decibels (dB) of shielding. The composites were also shown to be adequate for most communications security applications. However, the addition of a seam decreased shielding by as much as 10 dB.« less

  2. A study of trade-specific occupational ergonomics considerations in the U.S. construction industry.

    PubMed

    Choi, Sang D

    2012-01-01

    The aim of this survey study was to identify trade-specific ergonomic issues, and discuss practical solutions to reduce work-related musculoskeletal disorders (WMSDs) and injuries in the construction industry. Thirty-two construction firms in the Midwestern United States completed the final survey questionnaire. Twelve different construction skilled trades participated included: general contractor, road, heavy and highway, concrete, electrical, carpentry, landscaping, plumbing, roofing, steel erection, street lighting/traffic signal, and utility construction. Total workforce of the participating companies numbered 11,118 employees. More than 90% of the participants in the survey had a written safety program; however, the majority of the firms did not have a trade-specific ergonomic intervention. The survey revealed that construction constructors perceived safety (worker well-being) as a high priority in their company. This study suggested that construction skilled-trade jobs the construction worker to employ trade-specific hand tools and working body positions that may contribute to different types of WMSD risks, body parts injured, and injury sources. Possible practical construction trade-specific ergonomic solutions might be considered includinge: selection of ergonomic hand tools, reduction of weight of construction materials, and promotion of wellness exercises. This paper may imply that need for more trade-specific ergonomics program elements to help alleviate the work-related musculoskeletal problems in the construction field.

  3. Ion Figuring of Replicated X-Ray Optics

    NASA Technical Reports Server (NTRS)

    Cantey, Thomas M.; Gregory, Don A.

    1997-01-01

    This investigation included experiments to demonstrate ion beam figuring effects on electroless nickel with the expressed desire to figure X-ray optic mandrels. It was important to establish that ion beam figuring did not induce any adverse effects to the nickel surface. The ion beam has consistently been shown to be an excellent indicator of the quality of the subsurface. Polishing is not the only cause for failure in the ion beam final figuring process, the material composition is equally important. Only by careful consideration of both these factors can the ion beam final figuring process achieve its greatest potential. The secondary goal was to construct a model for representing the ion beam material removal rate. Representing the ion beam removal rate is only an approximation and has a number of limiting factors. The resolution of the metrology apparatus limits the modeling of the beam function as well. As the surface error corrections demand more precision in the final figuring, the model representing beam function must be equally precise. The precision to which the beam function can be represented is not only determined by the model but also by the measurements producing that model. The method developed for determining the beam function has broad application to any material destined to be ion beam figured.

  4. Lunar vertical-shaft mining system

    NASA Technical Reports Server (NTRS)

    Introne, Steven D. (Editor); Krause, Roy; Williams, Erik; Baskette, Keith; Martich, Frederick; Weaver, Brad; Meve, Jeff; Alexander, Kyle; Dailey, Ron; White, Matt

    1994-01-01

    This report proposes a method that will allow lunar vertical-shaft mining. Lunar mining allows the exploitation of mineral resources imbedded within the surface. The proposed lunar vertical-shaft mining system is comprised of five subsystems: structure, materials handling, drilling, mining, and planning. The structure provides support for the exploration and mining equipment in the lunar environment. The materials handling subsystem moves mined material outside the structure and mining and drilling equipment inside the structure. The drilling process bores into the surface for the purpose of collecting soil samples, inserting transducer probes, or locating ore deposits. Once the ore deposits are discovered and pinpointed, mining operations bring the ore to the surface. The final subsystem is planning, which involves the construction of the mining structure.

  5. Nanoscale porosity in polymer films: fabrication and therapeutic applications

    PubMed Central

    Bernards, Daniel A.; Desai, Tejal A.

    2011-01-01

    This review focuses on current developments in the field of nanostructured bulk polymers and their application in bioengineering and therapeutic sciences. In contrast to well-established nanoscale materials, such as nanoparticles and nanofibers, bulk nanostructured polymers combine nanoscale structure in a macroscopic construct, which enables unique application of these materials. Contemporary fabrication and processing techniques capable of producing nanoporous polymer films are reviewed. Focus is placed on techniques capable of sub-100 nm features since this range approaches the size scale of biological components, such as proteins and viruses. The attributes of these techniques are compared, with an emphasis on the characteristic advantages and limitations of each method. Finally, application of these materials to biofiltration, immunoisolation, and drug delivery are reviewed. PMID:22140398

  6. Methane digester for wastewater grown aquatic plants. Final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1976-01-01

    The purpose of this project was to build and test a small-scale, prototype anaerobic digester using wastewater grown aquatic plants as feed stock. Two 150 gal. digesters of the horizontal ''bag'' shape were constructed and fed with water hyacinths and duckweed plants grown on wastewater. Bio-films were added to increase methane bacteria surface attachment area, and solar heating was used to increase operating temperatures. Repeated difficulties were encountered with the low cost materials and construction techniques used, causing leaks of liquids and methane gas, and in the solar heat exchanger. As a consequence, no reliable data were obtained on performance.more » Due to an inadequate budget, the project was terminated without making construction changes needed to properly operate the system for a long period of time. 15 refs., 7 figs.« less

  7. Continuum modeling of the mechanical and thermal behavior of discrete large structures

    NASA Technical Reports Server (NTRS)

    Nayfeh, A. H.; Hefzy, M. S.

    1980-01-01

    In the present paper we introduce a rather straightforward construction procedure in order to derive continuum equivalence of discrete truss-like repetitive structures. Once the actual structure is specified, the construction procedure can be outlined by the following three steps: (a) all sets of parallel members are identified, (b) unidirectional 'effective continuum' properties are derived for each of these sets and (c) orthogonal transformations are finally used to determine the contribution of each set to the 'overall effective continuum' properties of the structure. Here the properties includes mechanical (stiffnesses), thermal (coefficients of thermal expansions) and material densities. Once expanded descriptions of the steps (b) and (c) are done, the construction procedure will be applied to a wide variety of discrete structures and the results will be compared with those of other existing methods.

  8. High-Fidelity Geometric Modeling and Mesh Generation for Mechanics Characterization of Polycrystalline Materials

    DTIC Science & Technology

    2015-01-07

    and anisotropic quadrilateral meshes, which can be used as the control mesh for high-order T- spline surface modeling. Archival publications (published...anisotropic T-meshes for the further T- spline surface construction. Finally, a gradient flow-based method is developed to improve the T-mesh quality...shade-off. Halos are bright or dark thin regions around the boundary of the sample. These false edges around the object make many segmentation

  9. Environmental and Geotechnical Assessment of the Steel Slags as a Material for Road Structure

    PubMed Central

    Sas, Wojciech; Głuchowski, Andrzej; Radziemska, Maja; Dzięcioł, Justyna; Szymański, Alojzy

    2015-01-01

    Slags are the final solid wastes from the steel industry. Their production from waste and associated materials is a proper implementation of the basic objectives and principles of the waste management. This study aims to investigate the chemical and selected significant geotechnical parameters of steel slag as the alternative materials used in road construction. These investigations are strongly desired for successful application in engineering. Young’s modules E, and resilient modules Mr showed that their values corresponding with requirements for subbase (principal or auxiliary) and riding surface as well. Tested mechanical properties were conducted in soaked and un-soaked (optimal moisture content) conditions. The designated high content of chromium and zinc are strongly associated with the internal crystal structure of steel slag. The results do not lead to threats when they are applied in roads’ structures. Mechanical characterization was obtained by performing California bearing ratio (CBR) tests for steel slag in fixed compaction and moisture content conditions. Moreover, cyclic loading of steel slag was conducted with the application of cyclic California bearing ratio (cCBR) apparatus to characterization of this material as a controlled low-strength material. Finally, field studies that consist of static load plate VSS tests were presented. PMID:28793477

  10. Electrospinning: An enabling nanotechnology platform for drug delivery and regenerative medicine.

    PubMed

    Chen, Shixuan; Li, Ruiquan; Li, Xiaoran; Xie, Jingwei

    2018-05-02

    Electrospinning provides an enabling nanotechnology platform for generating a rich variety of novel structured materials in many biomedical applications including drug delivery, biosensing, tissue engineering, and regenerative medicine. In this review article, we begin with a thorough discussion on the method of producing 1D, 2D, and 3D electrospun nanofiber materials. In particular, we emphasize on how the 3D printing technology can contribute to the improvement of traditional electrospinning technology for the fabrication of 3D electrospun nanofiber materials as drug delivery devices/implants, scaffolds or living tissue constructs. We then highlight several notable examples of electrospun nanofiber materials in specific biomedical applications including cancer therapy, guiding cellular responses, engineering in vitro 3D tissue models, and tissue regeneration. Finally, we finish with conclusions and future perspectives of electrospun nanofiber materials for drug delivery and regenerative medicine. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Large-core single-mode rib SU8 waveguide using solvent-assisted microcontact molding.

    PubMed

    Huang, Cheng-Sheng; Wang, Wei-Chih

    2008-09-01

    This paper describes a novel fabrication technique for constructing a polymer-based large-core single-mode rib waveguide. A negative tone SU8 photoresist with a high optical transmission over a large wavelength range and stable mechanical properties was used as a waveguide material. A waveguide was constructed by using a polydimethylsiloxane stamp combined with a solvent-assisted microcontact molding technique. The effects on the final pattern's geometry of four different process conditions were investigated. Optical simulations were performed using beam propagation method software. Single-mode beam propagation was observed at the output of the simulated waveguide as well as the actual waveguide through the microscope image.

  12. Final Report for Project titled High Thermal Conductivity Polymer Composites for Low-Cost Heat Exchangers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Thibaud-Erkey, Catherine; Alahyari, Abbas

    Heat exchangers (HXs) are critical components in a wide range of heat transfer applications, from HVAC (Heating Ventilation and Cooling) to automobiles to manufacturing plants. They require materials capable of transferring heat at high rates while also minimizing thermal expansion over the usage temperature range. Conventionally, metals are used for applications where effective and efficient heat exchange is required, since many metals exhibit thermal conductivity over 100 W/m K. While metal HXs are constantly being improved, they still have some inherent drawbacks due to their metal construction, in particular corrosion. Polymeric material can offer solution to such durability issues andmore » allow designs that cannot be afforded by metal construction either due to complexity or cost. A major drawback of polymeric material is their low thermal conductivity (0.1-0.5? W/mK) that would lead to large system size. Recent improvements in the area of filled polymers have highlighted the possibility to greatly improve the thermal conductivity of polymeric materials while retaining their inherent manufacturing advantage, and have been applied to heat sink applications. Therefore, the objective of this project was to develop a robust review of materials for the manufacturing of industrial and commercial non-metallic heat exchangers. This review consisted of material identification, literature evaluation, as well as empirical and model characterization, resulting in a database of relevant material properties and characteristics to provide guidance for future heat exchanger development.« less

  13. Directed assembly of bio-inspired hierarchical materials with controlled nanofibrillar architectures

    NASA Astrophysics Data System (ADS)

    Tseng, Peter; Napier, Bradley; Zhao, Siwei; Mitropoulos, Alexander N.; Applegate, Matthew B.; Marelli, Benedetto; Kaplan, David L.; Omenetto, Fiorenzo G.

    2017-05-01

    In natural systems, directed self-assembly of structural proteins produces complex, hierarchical materials that exhibit a unique combination of mechanical, chemical and transport properties. This controlled process covers dimensions ranging from the nano- to the macroscale. Such materials are desirable to synthesize integrated and adaptive materials and systems. We describe a bio-inspired process to generate hierarchically defined structures with multiscale morphology by using regenerated silk fibroin. The combination of protein self-assembly and microscale mechanical constraints is used to form oriented, porous nanofibrillar networks within predesigned macroscopic structures. This approach allows us to predefine the mechanical and physical properties of these materials, achieved by the definition of gradients in nano- to macroscale order. We fabricate centimetre-scale material geometries including anchors, cables, lattices and webs, as well as functional materials with structure-dependent strength and anisotropic thermal transport. Finally, multiple three-dimensional geometries and doped nanofibrillar constructs are presented to illustrate the facile integration of synthetic and natural additives to form functional, interactive, hierarchical networks.

  14. An Innovative Time-Cost-Quality Tradeoff Modeling of Building Construction Project Based on Resource Allocation

    PubMed Central

    2014-01-01

    The time, quality, and cost are three important but contradictive objectives in a building construction project. It is a tough challenge for project managers to optimize them since they are different parameters. This paper presents a time-cost-quality optimization model that enables managers to optimize multiobjectives. The model is from the project breakdown structure method where task resources in a construction project are divided into a series of activities and further into construction labors, materials, equipment, and administration. The resources utilized in a construction activity would eventually determine its construction time, cost, and quality, and a complex time-cost-quality trade-off model is finally generated based on correlations between construction activities. A genetic algorithm tool is applied in the model to solve the comprehensive nonlinear time-cost-quality problems. Building of a three-storey house is an example to illustrate the implementation of the model, demonstrate its advantages in optimizing trade-off of construction time, cost, and quality, and help make a winning decision in construction practices. The computational time-cost-quality curves in visual graphics from the case study prove traditional cost-time assumptions reasonable and also prove this time-cost-quality trade-off model sophisticated. PMID:24672351

  15. Engineering 3D Cellularized Collagen Gels for Vascular Tissue Regeneration.

    PubMed

    Meghezi, Sébastien; Seifu, Dawit G; Bono, Nina; Unsworth, Larry; Mequanint, Kibret; Mantovani, Diego

    2015-06-16

    Synthetic materials are known to initiate clinical complications such as inflammation, stenosis, and infections when implanted as vascular substitutes. Collagen has been extensively used for a wide range of biomedical applications and is considered a valid alternative to synthetic materials due to its inherent biocompatibility (i.e., low antigenicity, inflammation, and cytotoxic responses). However, the limited mechanical properties and the related low hand-ability of collagen gels have hampered their use as scaffold materials for vascular tissue engineering. Therefore, the rationale behind this work was first to engineer cellularized collagen gels into a tubular-shaped geometry and second to enhance smooth muscle cells driven reorganization of collagen matrix to obtain tissues stiff enough to be handled. The strategy described here is based on the direct assembling of collagen and smooth muscle cells (construct) in a 3D cylindrical geometry with the use of a molding technique. This process requires a maturation period, during which the constructs are cultured in a bioreactor under static conditions (without applied external dynamic mechanical constraints) for 1 or 2 weeks. The "static bioreactor" provides a monitored and controlled sterile environment (pH, temperature, gas exchange, nutrient supply and waste removal) to the constructs. During culture period, thickness measurements were performed to evaluate the cells-driven remodeling of the collagen matrix, and glucose consumption and lactate production rates were measured to monitor the cells metabolic activity. Finally, mechanical and viscoelastic properties were assessed for the resulting tubular constructs. To this end, specific protocols and a focused know-how (manipulation, gripping, working in hydrated environment, and so on) were developed to characterize the engineered tissues.

  16. Characterization of materials formed by rice husk for construction

    NASA Astrophysics Data System (ADS)

    Portillo-Rodríguez, A. M.

    2013-11-01

    This review article delves into the use of agro-industrial wastes, which in construction field provides alternatives for environmental problems with the use of them. This fact enables development and lower costs for new options in the brick, cluster, mortar and concrete industry, what represents benefits for environment, housing and generally everything related to construction, looking for sustainability. For that reason a literature review is made to support the theme focusing on the use of rice husk in its natural, ground or ash state for manufacturing elements with clay masonry, precast and optimization of concrete and mortars. The technique used is based on scientific articles and researches found in reliable databases that were analyzed and integrated into a synthesized structure, which summarized the objectives, analysis processes, the physical and mechanical properties and finally the results. The conclusions are focused on potentiality of elements production in the construction development based on the high effectiveness like thermal insulation, low density and various benefits offered by high silica content pozzolanic properties, etc.

  17. Genotype Specification Language.

    PubMed

    Wilson, Erin H; Sagawa, Shiori; Weis, James W; Schubert, Max G; Bissell, Michael; Hawthorne, Brian; Reeves, Christopher D; Dean, Jed; Platt, Darren

    2016-06-17

    We describe here the Genotype Specification Language (GSL), a language that facilitates the rapid design of large and complex DNA constructs used to engineer genomes. The GSL compiler implements a high-level language based on traditional genetic notation, as well as a set of low-level DNA manipulation primitives. The language allows facile incorporation of parts from a library of cloned DNA constructs and from the "natural" library of parts in fully sequenced and annotated genomes. GSL was designed to engage genetic engineers in their native language while providing a framework for higher level abstract tooling. To this end we define four language levels, Level 0 (literal DNA sequence) through Level 3, with increasing abstraction of part selection and construction paths. GSL targets an intermediate language based on DNA slices that translates efficiently into a wide range of final output formats, such as FASTA and GenBank, and includes formats that specify instructions and materials such as oligonucleotide primers to allow the physical construction of the GSL designs by individual strain engineers or an automated DNA assembly core facility.

  18. Accelerated aging test results for aerospace wire insulation constructions

    NASA Technical Reports Server (NTRS)

    Dunbar, William G.

    1995-01-01

    Several wire insulation constructions were evaluated with and without continuous glow discharges at low pressure and high temperature to determine the aging characteristics of acceptable wire insulation constructions. It was known at the beginning of the test program that insulation aging takes several years when operated at normal ambient temperature and pressure of 20 C and 760 torr. Likewise, it was known that the accelerated aging process decreases insulation life by approximately 50% for each 10 C temperature rise. Therefore, the first phases of the program, not reported in these test results, were to select wire insulation constructions that could operate at high temperature and low pressure for over 10,000 hours with negligible shrinkage and little materials' deterioration.The final phase of the program was to determine accelerated aging characteristics. When an insulation construction is subjected to partial discharges the insulation is locally heated by the bombardment of the discharges, the insulation is also subjected to ozone and other deteriorating gas particles that may significantly increase the aging process. Several insulation systems using either a single material or combinations of teflon, kapton, and glass insulation constructions were tested. All constructions were rated to be partial discharge and/or corona-free at 240 volts, 400 Hz and 260 C (500 F) for 50, 000 hours at altitudes equivalent to the Paschen law. Minimum partial discharge aging tests were preceded by screening tests lasting 20 hours at 260 C. The aging process was accelerated by subjecting the test articles to temperatures up to 370 C (700 F) with and without partial discharges. After one month operation with continuous glow discharges surrounding the test articles, most insulation systems were either destroyed or became brittle, cracked, and unsafe for use. Time with space radiation as with partial discharges is accumulative.

  19. Accelerated aging test results for aerospace wire insulation constructions

    NASA Astrophysics Data System (ADS)

    Dunbar, William G.

    1995-11-01

    Several wire insulation constructions were evaluated with and without continuous glow discharges at low pressure and high temperature to determine the aging characteristics of acceptable wire insulation constructions. It was known at the beginning of the test program that insulation aging takes several years when operated at normal ambient temperature and pressure of 20 C and 760 torr. Likewise, it was known that the accelerated aging process decreases insulation life by approximately 50% for each 10 C temperature rise. Therefore, the first phases of the program, not reported in these test results, were to select wire insulation constructions that could operate at high temperature and low pressure for over 10,000 hours with negligible shrinkage and little materials' deterioration.The final phase of the program was to determine accelerated aging characteristics. When an insulation construction is subjected to partial discharges the insulation is locally heated by the bombardment of the discharges, the insulation is also subjected to ozone and other deteriorating gas particles that may significantly increase the aging process. Several insulation systems using either a single material or combinations of teflon, kapton, and glass insulation constructions were tested. All constructions were rated to be partial discharge and/or corona-free at 240 volts, 400 Hz and 260 C (500 F) for 50, 000 hours at altitudes equivalent to the Paschen law. Minimum partial discharge aging tests were preceded by screening tests lasting 20 hours at 260 C. The aging process was accelerated by subjecting the test articles to temperatures up to 370 C (700 F) with and without partial discharges. After one month operation with continuous glow discharges surrounding the test articles, most insulation systems were either destroyed or became brittle, cracked, and unsafe for use. Time with space radiation as with partial discharges is accumulative.

  20. A rule-based expert system applied to moisture durability of building envelopes

    DOE PAGES

    Boudreaux, Philip R.; Pallin, Simon B.; Accawi, Gina K.; ...

    2018-01-09

    The moisture durability of an envelope component such as a wall or roof is difficult to predict. Moisture durability depends on all the construction materials used, as well as the climate, orientation, air tightness, and indoor conditions. Modern building codes require more insulation and tighter construction but provide little guidance about how to ensure these energy-efficient assemblies remain moisture durable. Furthermore, as new products and materials are introduced, builders are increasingly uncertain about the long-term durability of their building envelope designs. Oak Ridge National Laboratory and the US Department of Energy’s Building America Program are applying a rule-based expert systemmore » methodology in a web tool to help designers determine whether a given wall design is likely to be moisture durable and provide expert guidance on moisture risk management specific to a wall design and climate. Finally, the expert system is populated with knowledge from both expert judgment and probabilistic hygrothermal simulation results.« less

  1. Design and construction of a new steady-state apparatus for medium thermal conductivity measurement at high temperature.

    PubMed

    Wang, Yong; Xiao, Peng; Dai, Jingmin

    2017-10-01

    A new steady-state apparatus is designed and constructed for the measurement of thermal conductivity (up to 25 W/mK) on a square specimen (300 mm side) with a heating temperature range from 30 °C to 900 °C. A vacuum container, of which the pressure can reach to 1 Pa, is also built for materials which can be easily oxidized. The structure of the facility is different from that of traditional steady-state devices, especially for the design of heating plate and heat sink. To verify the temperature uniformity of the heating plate, a simulation analysis is carried out in this paper. Besides, the heating system, the heat sink, the measuring system, and the vacuum system are presented in detail. In addition, the thermal conductivities of a heat insulation tile, 304L stainless steel, n-docosane, and erythritol are measured by this apparatus. Finally, an uncertainty analysis is discussed depending on different temperatures and materials.

  2. Design and construction of a new steady-state apparatus for medium thermal conductivity measurement at high temperature

    NASA Astrophysics Data System (ADS)

    Wang, Yong; Xiao, Peng; Dai, Jingmin

    2017-10-01

    A new steady-state apparatus is designed and constructed for the measurement of thermal conductivity (up to 25 W/mK) on a square specimen (300 mm side) with a heating temperature range from 30 °C to 900 °C. A vacuum container, of which the pressure can reach to 1 Pa, is also built for materials which can be easily oxidized. The structure of the facility is different from that of traditional steady-state devices, especially for the design of heating plate and heat sink. To verify the temperature uniformity of the heating plate, a simulation analysis is carried out in this paper. Besides, the heating system, the heat sink, the measuring system, and the vacuum system are presented in detail. In addition, the thermal conductivities of a heat insulation tile, 304L stainless steel, n-docosane, and erythritol are measured by this apparatus. Finally, an uncertainty analysis is discussed depending on different temperatures and materials.

  3. A rule-based expert system applied to moisture durability of building envelopes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Boudreaux, Philip R.; Pallin, Simon B.; Accawi, Gina K.

    The moisture durability of an envelope component such as a wall or roof is difficult to predict. Moisture durability depends on all the construction materials used, as well as the climate, orientation, air tightness, and indoor conditions. Modern building codes require more insulation and tighter construction but provide little guidance about how to ensure these energy-efficient assemblies remain moisture durable. Furthermore, as new products and materials are introduced, builders are increasingly uncertain about the long-term durability of their building envelope designs. Oak Ridge National Laboratory and the US Department of Energy’s Building America Program are applying a rule-based expert systemmore » methodology in a web tool to help designers determine whether a given wall design is likely to be moisture durable and provide expert guidance on moisture risk management specific to a wall design and climate. Finally, the expert system is populated with knowledge from both expert judgment and probabilistic hygrothermal simulation results.« less

  4. Additive Manufacturing Solutions in the United States Marine Corps

    DTIC Science & Technology

    2017-12-01

    4 demonstrates this process. A laser or a blade then cuts each layer to shape the final product. Wohlers (2017) states that “the cost of material is...printed sole for its running shoes. The top of the shoe is constructed from conventional fabric and is attached to the sole after it is printed...milling). This runs on 208 volts and provides a small work area (T. Arndt, personal communication, June 21, 2017). 1st Maintenance Battalion Marines

  5. 46 CFR Appendix II to Part 390 - Sample Capital Construction Fund Agreement

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...) In the case of a vessel constructed or acquired within one year of final delivery from the shipyard... date of such vessel's final delivery; (2) In the case of a vessel reconstructed or acquired more than one year after final delivery from the shipyard after construction with the aid of qualified...

  6. 46 CFR Appendix II to Part 390 - Sample Capital Construction Fund Agreement

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) In the case of a vessel constructed or acquired within one year of final delivery from the shipyard... date of such vessel's final delivery; (2) In the case of a vessel reconstructed or acquired more than one year after final delivery from the shipyard after construction with the aid of qualified...

  7. 78 FR 23837 - Cranes and Derricks in Construction: Underground Construction and Demolition

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-23

    ... report here the results for the entire heavy-and-civil engineering sector and the entire site... in this final rule because employers included in the heavy-and-civil engineering sector, or the site... final rule. This final rule affects two construction sectors: NAICS 237990 (Other Heavy and Civil...

  8. 76 FR 58537 - In the Matter of Certain Personal Data and Mobile Communications Devices and Related Software...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-21

    ... subsystems. (HTC Pet. 30-35). (4) Whether the final ID's applications of the claim constructions for... below: (1) Whether the final ID's applications of the claim constructions for ``linking actions to the... has determined to review certain claim constructions, as well as the final ID's determinations...

  9. Development of the Patient Education Materials Assessment Tool (PEMAT): A new measure of understandability and actionability for print and audiovisual patient information

    PubMed Central

    Shoemaker, Sarah J.; Wolf, Michael S.; Brach, Cindy

    2016-01-01

    Objective To develop a reliable and valid instrument to assess the understandability and actionability of print and audiovisual materials. Methods We compiled items from existing instruments/guides that the expert panel assessed for face/content validity. We completed four rounds of reliability testing, and produced evidence of construct validity with consumers and readability assessments. Results The experts deemed the PEMAT items face/content valid. Four rounds of reliability testing and refinement were conducted using raters untrained on the PEMAT. Agreement improved across rounds. The final PEMAT showed moderate agreement per Kappa (Average K = 0.57) and strong agreement per Gwet’s AC1 (Average = 0.74). Internal consistency was strong (α = 0.71; Average Item-Total Correlation = 0.62). For construct validation with consumers (n = 47), we found significant differences between actionable and poorly-actionable materials in comprehension scores (76% vs. 63%, p < 0.05) and ratings (8.9 vs. 7.7, p < 0.05). For understandability, there was a significant difference for only one of two topics on consumer numeric scores. For actionability, there were significant positive correlations between PEMAT scores and consumer-testing results, but no relationship for understandability. There were, however, strong, negative correlations between grade-level and both consumer-testing results and PEMAT scores. Conclusions The PEMAT demonstrated strong internal consistency, reliability, and evidence of construct validity. Practice implications The PEMAT can help professionals judge the quality of materials (available at: http://www.ahrq.gov/pemat). PMID:24973195

  10. Development of the Patient Education Materials Assessment Tool (PEMAT): a new measure of understandability and actionability for print and audiovisual patient information.

    PubMed

    Shoemaker, Sarah J; Wolf, Michael S; Brach, Cindy

    2014-09-01

    To develop a reliable and valid instrument to assess the understandability and actionability of print and audiovisual materials. We compiled items from existing instruments/guides that the expert panel assessed for face/content validity. We completed four rounds of reliability testing, and produced evidence of construct validity with consumers and readability assessments. The experts deemed the PEMAT items face/content valid. Four rounds of reliability testing and refinement were conducted using raters untrained on the PEMAT. Agreement improved across rounds. The final PEMAT showed moderate agreement per Kappa (Average K=0.57) and strong agreement per Gwet's AC1 (Average=0.74). Internal consistency was strong (α=0.71; Average Item-Total Correlation=0.62). For construct validation with consumers (n=47), we found significant differences between actionable and poorly-actionable materials in comprehension scores (76% vs. 63%, p<0.05) and ratings (8.9 vs. 7.7, p<0.05). For understandability, there was a significant difference for only one of two topics on consumer numeric scores. For actionability, there were significant positive correlations between PEMAT scores and consumer-testing results, but no relationship for understandability. There were, however, strong, negative correlations between grade-level and both consumer-testing results and PEMAT scores. The PEMAT demonstrated strong internal consistency, reliability, and evidence of construct validity. The PEMAT can help professionals judge the quality of materials (available at: http://www.ahrq.gov/pemat). Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  11. Physical Training Methods For Mine Rescuers In 2015

    NASA Astrophysics Data System (ADS)

    Marin, Laurentiu; Pavel, Topala; Marin, Catalina Daniela; Sandu, Teodor

    2015-07-01

    Research and development activities presented were aimed at obtaining a nanocomposite polyurethane matrix with special anti-wear, anti-slip and fire-resistant properties. Research and development works were materialized by obtaining polyurethane nanocomposite matrix, by its physico-chemical modification in order to give the desired technological properties and by characterization of the obtained material. Polyurethane nanocomposite matrix was obtained by reacting a PETOL 3 type polyetherpolyol (having a molecular weight of 5000 UAM) with a diisocyanate under well-established reaction conditions. Target specific technological properties were obtained by physical and chemical modification of polyurethane nanocomposite matrix. The final result was getting a pellicle material based on modified nanocomposite polyurethane, with anti-wear, anti-slip and fire-resistant properties, compatible with most substrates encountered in civil and industrial construction: wood, concrete, metal.

  12. Construction and validation of clinical contents for development of learning objects.

    PubMed

    Hortense, Flávia Tatiana Pedrolo; Bergerot, Cristiane Decat; Domenico, Edvane Birelo Lopes de

    2018-01-01

    to describe the process of construction and validation of clinical contents for health learning objects, aimed at patients in the treatment of head and neck cancer. descriptive, methodological study. The development of the script and the storyboard were based on scientific evidence and submitted to the appreciation of specialists for validation of content. The agreement index was checked quantitatively and the suggestions were qualitatively evaluated. The items described in the roadmap were approved by 99% of expert experts. The suggestions for adjustments were inserted in their entirety in the final version. The free-marginal kappa statistical test, for multiple evaluators, presented value equal to 0.68%, granting a substantial agreement. The steps taken in the construction and validation of the content for the production of educational material for patients with head and neck cancer were adequate, relevant and suitable for use in other subjects.

  13. Tale taming radioactive fears: Linking nuclear waste disposal to the "continuum of the good".

    PubMed

    Yli-Kauhaluoma, Sari; Hänninen, Hannu

    2014-04-01

    We examine how the constructor of the world's first repository for the final disposal of spent nuclear fuel in Eurajoki, Finland, aims to shape lay understanding of the facility's risks and to tame the nuclear fears of the local community by producing positive associations, imagery and tales. Our empirical material consists of the constructor's newsletters targeted mainly at the local residents. In the narrative analysis, we identified a storyline where the construction of the repository is linked into the "continuum of the good" in the municipality of the construction site and the surrounding areas. The storyline consists of five different themes all emphasizing the "continuum of the good" in the area: cultural heritage, well-being, developing expertise, natural environment, and local families. Our study contributes to the literature on pro-nuclear storytelling by showing how the inclination is towards narratives that are constructed around local symbols, cultural landmarks, and institutions.

  14. Composite Bus Structure for the SMEX/WIRE Satellite

    NASA Technical Reports Server (NTRS)

    Rosanova, Giulio G.

    1998-01-01

    In an effort to reduce the weight and optimize the structural design of the Small Explorer (SMEX) Wide-Field Infrared Explorer (WIRE) spacecraft, it has become desirable to change the material and construction from mechanically fastened aluminum structure to a fully bonded fiber-reinforced composite (FRC) structure. GSFC has developed the WIRE spacecraft structural bus design concept, including the instrument and launch vehicle requirements. The WIRE Satellite is the fifth of a series of SMEX satellites to be launched once per year. GSFC has chosen Composite Optics Inc. (COI) as the prime contractor for the development and procurement of the WIRE composite structure. The detailed design of the fully bonded FRC structure is based on COI's Short Notice Accelerated Production SATellite ("SNAPSAT") approach. SNAPSAT is a state of the art design and manufacturing technology for advanced composite materials which utilizes flat-stock detail parts bonded together to produce a final structural assembly. The structural design approach adopted for the WIRE structure provides a very viable alternative to both traditional aluminum construction as well as high tech. molded type composite structures. This approach to composite structure design is much less costly than molded or honeycomb sandwich type composite construction, but may cost slightly more than conventional aluminum construction on the subsystem level. However on the overall program level the weight saving achieved is very cost effective, since the primary objective is to allocate more mass for science payloads.

  15. An inverse method for determining the spatially resolved properties of viscoelastic–viscoplastic three-dimensional printed materials

    PubMed Central

    Chen, X.; Ashcroft, I. A.; Wildman, R. D.; Tuck, C. J.

    2015-01-01

    A method using experimental nanoindentation and inverse finite-element analysis (FEA) has been developed that enables the spatial variation of material constitutive properties to be accurately determined. The method was used to measure property variation in a three-dimensional printed (3DP) polymeric material. The accuracy of the method is dependent on the applicability of the constitutive model used in the inverse FEA, hence four potential material models: viscoelastic, viscoelastic–viscoplastic, nonlinear viscoelastic and nonlinear viscoelastic–viscoplastic were evaluated, with the latter enabling the best fit to experimental data. Significant changes in material properties were seen in the depth direction of the 3DP sample, which could be linked to the degree of cross-linking within the material, a feature inherent in a UV-cured layer-by-layer construction method. It is proposed that the method is a powerful tool in the analysis of manufacturing processes with potential spatial property variation that will also enable the accurate prediction of final manufactured part performance. PMID:26730216

  16. Development of a 3D muon disappearance algorithm for muon scattering tomography

    NASA Astrophysics Data System (ADS)

    Blackwell, T. B.; Kudryavtsev, V. A.

    2015-05-01

    Upon passing through a material, muons lose energy, scatter off nuclei and atomic electrons, and can stop in the material. Muons will more readily lose energy in higher density materials. Therefore multiple muon disappearances within a localized volume may signal the presence of high-density materials. We have developed a new technique that improves the sensitivity of standard muon scattering tomography. This technique exploits these muon disappearances to perform non-destructive assay of an inspected volume. Muons that disappear have their track evaluated using a 3D line extrapolation algorithm, which is in turn used to construct a 3D tomographic image of the inspected volume. Results of Monte Carlo simulations that measure muon disappearance in different types of target materials are presented. The ability to differentiate between different density materials using the 3D line extrapolation algorithm is established. Finally the capability of this new muon disappearance technique to enhance muon scattering tomography techniques in detecting shielded HEU in cargo containers has been demonstrated.

  17. An inverse method for determining the spatially resolved properties of viscoelastic-viscoplastic three-dimensional printed materials.

    PubMed

    Chen, X; Ashcroft, I A; Wildman, R D; Tuck, C J

    2015-11-08

    A method using experimental nanoindentation and inverse finite-element analysis (FEA) has been developed that enables the spatial variation of material constitutive properties to be accurately determined. The method was used to measure property variation in a three-dimensional printed (3DP) polymeric material. The accuracy of the method is dependent on the applicability of the constitutive model used in the inverse FEA, hence four potential material models: viscoelastic, viscoelastic-viscoplastic, nonlinear viscoelastic and nonlinear viscoelastic-viscoplastic were evaluated, with the latter enabling the best fit to experimental data. Significant changes in material properties were seen in the depth direction of the 3DP sample, which could be linked to the degree of cross-linking within the material, a feature inherent in a UV-cured layer-by-layer construction method. It is proposed that the method is a powerful tool in the analysis of manufacturing processes with potential spatial property variation that will also enable the accurate prediction of final manufactured part performance.

  18. A Framework to Evaluate the Impact of Armourstones on the Chemical Quality of Surface Water.

    PubMed

    Duester, Lars; Wahrendorf, Dierk-Steffen; Brinkmann, Corinna; Fabricius, Anne-Lena; Meermann, Björn; Pelzer, Juergen; Ecker, Dennis; Renner, Monika; Schmid, Harald; Ternes, Thomas A; Heininger, Peter

    2017-01-01

    Today, basic requirements for construction works include the protection of human health and of the environment. In the tension area between economic demands, circular flow economy and environmental safety, a link between the results from standardized leaching tests and the respective environmental quality standards must be created. To derive maximum release limits of metals and metalloids for armourstones in hydraulic engineering, this link is accomplished via a simple model approach. By treating natural materials and industrial by-products the same way, the article delivers an overview on the recent regulative situation in Europe as well as describes and discusses an innovative approach to derive maximum release limits for monolithic construction products in hydraulic engineering on a conceptual level. On a practical level, a list of test parameters is derived by connecting an extensive dataset (seven armourstone materials with five repetitions and 31 elements tested with the worldwide applied dynamic surface leaching test) with surface water quality standards and predicted no effect concentrations. Finally, the leaching tests results are compared with the envisaged maximum release limits, offering a direct comparison between natural materials and industrial by-products.

  19. Lunar construction utility vehicle

    NASA Technical Reports Server (NTRS)

    1989-01-01

    The lunar construction utility vehicle (LCUV) is an all-purpose construction vehicle which will aid in the robotic assembly of a lunar outpost. The LCUV will have the following capabilities: (1) must be self supporting including repairs; (2) must offload itself from a lunar lander; (3) must be telerobotic and semi-autonomous; (4) must be able to transport one space station common module; (5) must allow for man-rated operation; and (6) must be able to move lunar regolith for site preparation. This study recommends the use of an elastic tracked vehicle. Detailed material analyses of most of the LCUV components were accomplished. The body frame, made of pinned truss elements, was stress analyzed using NASTRAN. A track connection system was developed; however, kinematic and stress analyses are still required. This design recommends the use of hydrogen-oxygen fuel cells for power. Thermal control has proven to be a problem which may be the most challenging technically. A tentative solution has been proposed which utilizes an onboard and towable radiator. Detailed study of the heat dissipation requirements is needed to finalize radiator sizing. Preliminary work on a man-rated cabin has begun; however, this is not required during the first mission phase of the LCUV. Finally, still in the conceptual phases, are the communication, navigation and mechanical arm systems.

  20. 49 CFR 268.21 - Down-selection of one or more Maglev projects for further study and selection of one project for...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... further study and selection of one project for final design, engineering, and construction funding. 268.21... and selection of one project for final design, engineering, and construction funding. (a) Upon... analyses necessary prior to initiation of construction. Final design and engineering work will also be...

  1. 49 CFR 268.21 - Down-selection of one or more Maglev projects for further study and selection of one project for...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... further study and selection of one project for final design, engineering, and construction funding. 268.21... and selection of one project for final design, engineering, and construction funding. (a) Upon... analyses necessary prior to initiation of construction. Final design and engineering work will also be...

  2. 49 CFR 268.21 - Down-selection of one or more Maglev projects for further study and selection of one project for...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... further study and selection of one project for final design, engineering, and construction funding. 268.21... and selection of one project for final design, engineering, and construction funding. (a) Upon... analyses necessary prior to initiation of construction. Final design and engineering work will also be...

  3. 49 CFR 268.21 - Down-selection of one or more Maglev projects for further study and selection of one project for...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... further study and selection of one project for final design, engineering, and construction funding. 268.21... and selection of one project for final design, engineering, and construction funding. (a) Upon... analyses necessary prior to initiation of construction. Final design and engineering work will also be...

  4. 49 CFR 268.21 - Down-selection of one or more Maglev projects for further study and selection of one project for...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... further study and selection of one project for final design, engineering, and construction funding. 268.21... and selection of one project for final design, engineering, and construction funding. (a) Upon... analyses necessary prior to initiation of construction. Final design and engineering work will also be...

  5. 4D bioprinting: the next-generation technology for biofabrication enabled by stimuli-responsive materials.

    PubMed

    Li, Yi-Chen; Zhang, Yu Shrike; Akpek, Ali; Shin, Su Ryon; Khademhosseini, Ali

    2016-12-02

    Four-dimensional (4D) bioprinting, encompassing a wide range of disciplines including bioengineering, materials science, chemistry, and computer sciences, is emerging as the next-generation biofabrication technology. By utilizing stimuli-responsive materials and advanced three-dimensional (3D) bioprinting strategies, 4D bioprinting aims to create dynamic 3D patterned biological structures that can transform their shapes or behavior under various stimuli. In this review, we highlight the potential use of various stimuli-responsive materials for 4D printing and their extension into biofabrication. We first discuss the state of the art and limitations associated with current 3D printing modalities and their transition into the inclusion of the additional time dimension. We then suggest the potential use of different stimuli-responsive biomaterials as the bioink that may achieve 4D bioprinting where transformation of fabricated biological constructs can be realized. We finally conclude with future perspectives.

  6. Correlation of the Processing Parameters in the Formation of Granulated Ground Blast Furnace Slag Geopolymer

    NASA Astrophysics Data System (ADS)

    Aziz, I. H.; Abdullah, M. M. A. B.; Yong, H. C.; Ming, L. Y.; Panias, D.; Sakkas, K.

    2017-06-01

    Geopolymers are inorganic materials with huge potential applications including building material, fire resistant materials, and agricultural construction materials. Various parameters influenced the final properties of these geopolymer concretes. This study developed the effects of several factors such as solid-to-liquid ratio, NaOH concentration, and Na2SiO3/NaOH ratio on the compressive strength of granulated ground blast furnace slag (GGBFS) by statistical design of experiment (DOE) approach. Analysis of the experimental results through ANOVA exhibited that the specimen with NaOH concentration of 10M, Na2SiO3/NaOH ratio equals to 2.5, and solid-to-liquid ratio of 3.0 curing at room temperatures for 28 days was potential of highest strength (168.705 MPa) in the considered procedure. Besides, the relationship between compressive strength and influential factors could be suitably by fraction factorial design method.

  7. Apparatus and Method for Increasing the Diameter of Metal Alloy Wires Within a Molten Metal Pool

    DOEpatents

    Hartman, Alan D.; Argetsinger, Edward R.; Hansen, Jeffrey S.; Paige, Jack I.; King, Paul E.; Turner, Paul C.

    2002-01-29

    In a dip forming process the core material to be coated is introduced directly into a source block of coating material eliminating the need for a bushing entrance component. The process containment vessel or crucible is heated so that only a portion of the coating material becomes molten, leaving a solid portion of material as the entrance port of, and seal around, the core material. The crucible can contain molten and solid metals and is especially useful when coating core material with reactive metals. The source block of coating material has been machined to include a close tolerance hole of a size and shape to closely fit the core material. The core material moves first through the solid portion of the source block of coating material where the close tolerance hole has been machined, then through a solid/molten interface, and finally through the molten phase where the diameter of the core material is increased. The crucible may or may not require water-cooling depending upon the type of material used in crucible construction. The system may operate under vacuum, partial vacuum, atmospheric pressure, or positive pressure depending upon the type of source material being used.

  8. Apparatus and method for increasing the diameter of metal alloy wires within a molten metal pool

    DOEpatents

    Hartman, Alan D.; Argetsinger, Edward R.; Hansen, Jeffrey S.; Paige, Jack I.; King, Paul E.; Turner, Paul C.

    2002-01-29

    In a dip forming process the core material to be coated is introduced directly into a source block of coating material eliminating the need for a bushing entrance component. The process containment vessel or crucible is heated so that only a portion of the coating material becomes molten, leaving a solid portion of material as the entrance port of, and seal around, the core material. The crucible can contain molten and solid metals and is especially useful when coating core material with reactive metals. The source block of coating material has been machined to include a close tolerance hole of a size and shape to closely fit the core material. The core material moves first through the solid portion of the source block of coating material where the close tolerance hole has been machined, then through a solid/molten interface, and finally through the molten phase where the diameter of the core material is increased. The crucible may or may not require water-cooling depending upon the type of material used in crucible construction. The system may operate under vacuum, partial vacuum, atmospheric pressure, or positive pressure depending upon the type of source material being used.

  9. Kevlar/PMR-15 polyimide matrix composite for a complex shaped DC-9 drag reduction fairing

    NASA Technical Reports Server (NTRS)

    Kawai, R. T.; Mccarthy, R. F.; Willer, M. S.; Hrach, F. J.

    1982-01-01

    The Aircraft Energy Efficiency (ACEE) Program was established by NASA to improve the fuel efficiency of commercial transport aircraft and thereby to reduce the amount of fuel consumed by the air transportation industry. One of the final items developed by the program is an improved fairing which is the aft closure for the thrust reverser actuators on the JT8D nacelles on DC-9 aircraft. The reduced-drag fairing uses, in the interest of weight savings, an advanced composite construction. The composite material contains Kevlar 49 fibers in a PMR-15 matrix. Attention is given to the aerodynamic configuration, the material system, and aspects of fabrication development.

  10. Reassessing the Representative Heuristic of the Plywood Ballistic Mannequin Used in Live-Fire Testing

    DTIC Science & Technology

    2015-04-01

    currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) April 2015 2. REPORT TYPE Final 3...the materials of construction of the current plywood ballistic mannequin (or manikin) should be more closely controlled and 2) to revise the US Army...Inappropriate 33 Appendix B. The American Plywood Association (APA) Wood Species Grouping 37 Appendix C. US Army Ballistic Research Laboratory (BRL) Plywood

  11. Mythical systems: mathematic and logical theory

    NASA Astrophysics Data System (ADS)

    Nescolarde-Selva, J.; Usó-Doménech, J. L.; Lloret-Climent, M.

    2015-01-01

    The process of elaboration of the symbolic universe leads to exciting insights regarding the search for human emotional security. The symbols end up as explanatory axes of universal reality and on them are constructed myths that form a superstructure for belief systems. Human society is a multi-level system with a material structure (society), an ideological superstructure (belief systems, values, etc.) and a super superstructure with two parts: mythical (origin and justification) and utopic (final goal). All mythical belief systems have a numinous-religious nature.

  12. Thermal management and mechanical structures for silicon detector systems

    NASA Astrophysics Data System (ADS)

    Viehhauser, G.

    2015-09-01

    Due to the size of current silicon tracking systems system aspects have become a major design driver. This article discusses requirements for the engineering of the mechanical structures and thermal management of such systems and reviews solutions developed to satisfy them. Modern materials and fabrication techniques have been instrumental in constructing these devices and will be discussed here. Finally, this paper will describe current and potential future developments in the engineering of silicon tracking systems which will shape the silicon tracking systems of the future.

  13. Composite material pedestrian bridge for the Port of Bilbao

    NASA Astrophysics Data System (ADS)

    Gorrochategui, I.; Manteca, C.; Yedra, A.; Miguel, R.; del Valle, F. J.

    2012-09-01

    Composite materials in comparison to traditional ones, steel and concrete, present advantages in civil works construction: lower weight, higher corrosion resistance (especially in the marine environment), and ease of installation. On the other hand, fabrication costs are generally higher. This is the reason why this technology is not widely used. This work illustrates the process followed for the design, fabrication and installation of a composite material pedestrian bridge in the Port of Bilbao (Northern Spain). In order to reduce the price of the bridge, the use of low cost materials was considered, therefore polyester resin was selected as the polymeric matrix, and glass fibres as reinforcement. Two material choices were studied. Currently in the market there is high availability of carbon nanoparticles: carbon nanotubes (CNT) and carbon nanofibres (CNF), so it was decided to add this kind of nanoparticles to the reference material with the objective of improving its mechanical properties. The main challenge was to transfer the CNT and CNF excellent properties to the polymeric matrix. This requires dispersing the nanoreinforcements as individual particles in the polymeric matrix to avoid agglomerates. For this reason, an advanced high shear forces dispersion technique (called "three roll mills") was studied and implemented. Also surface functionalization of the nanoreinforcements by chemical treatment was carried out. Herein, a comparison is performed between both materials studied, the explanation of the employment of the reference material (without nanoreinforcement) as the one used in the fabrication of the pedestrian bridge is justified and, finally, the main characteristics of the final design of the structural element are described.

  14. 46 CFR 160.062-3 - Materials, construction, workmanship, and performance requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 6 2010-10-01 2010-10-01 false Materials, construction, workmanship, and performance.... Lifesaving Equipment, Hydraulic and Manual § 160.062-3 Materials, construction, workmanship, and performance requirements. (a) General. The materials, construction, workmanship, and performance requirements shall conform...

  15. Research Progress of Building Materials Used in Construction Land

    NASA Astrophysics Data System (ADS)

    Niu, Yan

    2018-01-01

    Construction land preparation is an important aspect of land remediation project. The research of materials in the process of land improvement is the foundation and the core. Therefore, it is necessary to study the materials that may be involved in the process of building land preparation. In this paper, the research on the construction materials such as recycled concrete, geosynthetics, soil stabilizers, soil improvers, building insulation materials and inorganic fibrous insulation materials, which are commonly used in construction sites, is reviewed and discussed in this paper. Land remediation project involved in the construction of land materials to provide reference.

  16. Portland cement concrete pavement restoration : final summary report.

    DOT National Transportation Integrated Search

    1988-07-01

    This final summary report is comprised of an Initial Construction Report; a Final Report; and two Interim Reports. These reports document the construction of Louisiana's Portland Cement Concrete Pavement Restoration project and its performance during...

  17. 48 CFR 52.225-9 - Buy American Act-Construction Materials.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 1984 (46 U.S.C. App. 1702), such as agricultural products and petroleum products. Construction material... delivered to the construction site. Materials purchased directly by the Government are supplies, not construction material. Cost of components means— (1) For components purchased by the Contractor, the...

  18. Evaluation of Uncertainty in Bedload Transport Estimates in a Southern Appalachian Stream

    NASA Astrophysics Data System (ADS)

    Schwartz, J. S.

    2016-12-01

    Capacity estimates of bed-material transport rates are generally derived using empirical formulae as a function of bed material gradation and composition, and hydraulic shear stress. Various field techniques may be used to sample and characterize bed material gradation; some techniques assume the existing bar material is representative of that in transport. Other methods use Helly-Smith samplers, pit traps, and net traps. Very few large, complete cross-section pit traps fully instrumented to collect continuous bedload transport have been constructed, and none in the eastern United States to our knowledge. A fully-instrumented bedload collection station was constructed on Little Turkey Creek (LTC) in Farragut, Tennessee. The aim of the research was to characterize bed material transport during stormflows for a southern Appalachian stream in the Ridge and Valley Providence. Bedload transport data from LTC was compared with classic datasets including Oak Creek (Oregon), East Fork River (Wyoming), and Clearwater and Snake rivers (Idaho). In addition, data were evaluated to assess the potential accuracy of both calibrated and uncalibrated bedload transport models using bedload transport data from LTC. Uncalibrated models were assessed with regard to their estimated range of uncertainty according to Monte Carlo uncertainty analyses. Models calibrated using reference shear values determined according to station measurements are evaluated in the same manner. Finally, models calibrated using the small scale, short-term, low rate bedload sampling techniques promoted in the literature for the spreadsheet based Bedload Assessment in Gravel-bedded Streams (BAGS) software for determining the reference shear stress are compared to results of both uncalibrated models and those calibrated using data from the bedload station. This research supports design and construction of dynamically stable alluvial stream restoration projects where stream channels are largely dependent on reach-scale hydraulic geometry that provides a long-term balance between bed-material sediment supply and transport capacity.

  19. The Use Potential of Traditional Building Materials for the Realization of Structures by Modern Methods of Construction

    NASA Astrophysics Data System (ADS)

    Spišáková, Marcela; Mačková, Daniela

    2015-11-01

    The sustainable building has taken off in recent years with many investors looking for new and different methods of construction. The traditional building materials can be made out of natural materials, while others can help to lower energy costs of the occupant once built. Regardless of what the goal of the investor is, traditional building materials and their use is on the rise. The submitted paper provides an overview of natural building materials and possible modern building systems using these construction materials. Based on the questionnaire survey is defined the use potential of traditional building materials for the realization of the construction by methods of modern constructions and then are determined the drivers and barriers of traditional materials through using modern methods of construction. Considering the analysis of the achieved results, we can identify the gaps in the construction market in Slovakia and also to assess the perception of potential investors in the field of traditional building materials use, which is the purpose of submitted paper.

  20. Development of a thermosensitive HAMA-containing bio-ink for the fabrication of composite cartilage repair constructs.

    PubMed

    Mouser, V H M; Abbadessa, A; Levato, R; Hennink, W E; Vermonden, T; Gawlitta, D; Malda, J

    2017-03-23

    Fine-tuning of bio-ink composition and material processing parameters is crucial for the development of biomechanically relevant cartilage constructs. This study aims to design and develop cartilage constructs with tunable internal architectures and relevant mechanical properties. More specifically, the potential of methacrylated hyaluronic acid (HAMA) added to thermosensitive hydrogels composed of methacrylated poly[N-(2-hydroxypropyl)methacrylamide mono/dilactate] (pHPMA-lac)/polyethylene glycol (PEG) triblock copolymers, to optimize cartilage-like tissue formation by embedded chondrocytes, and enhance printability was explored. Additionally, co-printing with polycaprolactone (PCL) was performed for mechanical reinforcement. Chondrocyte-laden hydrogels composed of pHPMA-lac-PEG and different concentrations of HAMA (0%-1% w/w) were cultured for 28 d in vitro and subsequently evaluated for the presence of cartilage-like matrix. Young's moduli were determined for hydrogels with the different HAMA concentrations. Additionally, hydrogel/PCL constructs with different internal architectures were co-printed and analyzed for their mechanical properties. The results of this study demonstrated a dose-dependent effect of HAMA concentration on cartilage matrix synthesis by chondrocytes. Glycosaminoglycan (GAG) and collagen type II content increased with intermediate HAMA concentrations (0.25%-0.5%) compared to HAMA-free controls, while a relatively high HAMA concentration (1%) resulted in increased fibrocartilage formation. Young's moduli of generated hydrogel constructs ranged from 14 to 31 kPa and increased with increasing HAMA concentration. The pHPMA-lac-PEG hydrogels with 0.5% HAMA were found to be optimal for cartilage-like tissue formation. Therefore, this hydrogel system was co-printed with PCL to generate porous or solid constructs with different mesh sizes. Young's moduli of these composite constructs were in the range of native cartilage (3.5-4.6 MPa). Interestingly, the co-printing procedure influenced the mechanical properties of the final constructs. These findings are relevant for future bio-ink development, as they demonstrate the importance of selecting proper HAMA concentrations, as well as appropriate print settings and construct designs for optimal cartilage matrix deposition and final mechanical properties of constructs, respectively.

  1. 76 FR 13329 - Reinstatement of Coverage Pertaining to Final Payment Under Construction and Building Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-11

    ..., Release of Claims, for releases of claims under construction and building service contracts, was... prescribed the use of GSA Form 1142 for releases of claims under construction and building service contracts...] RIN 3090-AJ13 Reinstatement of Coverage Pertaining to Final Payment Under Construction and Building...

  2. Investigation of high temperature antennas for space shuttle

    NASA Technical Reports Server (NTRS)

    Kuhlman, E. A.

    1973-01-01

    The design and development of high temperature antennas for the space shuttle orbiter are discussed. The antenna designs were based on three antenna types, an annular slot (L-Band), a linear slot (C-Band), and a horn (C-Band). The design approach was based on combining an RF window, which provides thermal protection, with an off-the-shelf antenna. Available antenna window materials were reviewed and compared, and the materials most compatible with the design requirements were selected. Two antenna window design approaches were considered: one employed a high temperature dielectric material and a low density insulation material, and the other an insulation material usable for the orbiter thermal protection system. Preliminary designs were formulated and integrated into the orbiter structure. Simple electrical models, with a series of window configurations, were constructed and tested. The results of tests and analyses for the final antenna system designs are given and show that high temperature antenna systems consisting of off-the-shelf antennas thermally protected by RF windows can be designed for the Space Shuttle Orbiter.

  3. Study on Material Parameters Identification of Brain Tissue Considering Uncertainty of Friction Coefficient

    NASA Astrophysics Data System (ADS)

    Guan, Fengjiao; Zhang, Guanjun; Liu, Jie; Wang, Shujing; Luo, Xu; Zhu, Feng

    2017-10-01

    Accurate material parameters are critical to construct the high biofidelity finite element (FE) models. However, it is hard to obtain the brain tissue parameters accurately because of the effects of irregular geometry and uncertain boundary conditions. Considering the complexity of material test and the uncertainty of friction coefficient, a computational inverse method for viscoelastic material parameters identification of brain tissue is presented based on the interval analysis method. Firstly, the intervals are used to quantify the friction coefficient in the boundary condition. And then the inverse problem of material parameters identification under uncertain friction coefficient is transformed into two types of deterministic inverse problem. Finally the intelligent optimization algorithm is used to solve the two types of deterministic inverse problems quickly and accurately, and the range of material parameters can be easily acquired with no need of a variety of samples. The efficiency and convergence of this method are demonstrated by the material parameters identification of thalamus. The proposed method provides a potential effective tool for building high biofidelity human finite element model in the study of traffic accident injury.

  4. Constructing wetlands: measuring and modeling feedbacks of oxidation processes between plants and clay-rich material

    NASA Astrophysics Data System (ADS)

    Saaltink, Rémon; Dekker, Stefan C.; Griffioen, Jasper; Wassen, Martin J.

    2016-04-01

    Interest is growing in using soft sediment as a building material in eco-engineering projects. Wetland construction in the Dutch lake Markermeer is an example: here the option of dredging some of the clay-rich lake-bed sediment and using it to construct 10.000 ha of wetland will soon go under construction. Natural processes will be utilized during and after construction to accelerate ecosystem development. Knowing that plants can eco-engineer their environment via positive or negative biogeochemical plant-soil feedbacks, we conducted a six-month greenhouse experiment to identify the key biogeochemical processes in the mud when Phragmites australis is used as an eco-engineering species. We applied inverse biogeochemical modeling to link observed changes in pore water composition to biogeochemical processes. Two months after transplantation we observed reduced plant growth and shriveling as well as yellowing of foliage. The N:P ratios of plant tissue were low and were affected not by hampered uptake of N but by enhanced uptake of P. Plant analyses revealed high Fe concentrations in the leaves and roots. Sulfate concentrations rose drastically in our experiment due to pyrite oxidation; as reduction of sulfate will decouple Fe-P in reducing conditions, we argue that plant-induced iron toxicity hampered plant growth, forming a negative feedback loop, while simultaneously there was a positive feedback loop, as iron toxicity promotes P mobilization as a result of reduced conditions through root death, thereby stimulating plant growth and regeneration. Given these two feedback mechanisms, we propose that when building wetlands from these mud deposits Fe-tolerant species are used rather than species that thrive in N-limited conditions. The results presented in this study demonstrate the importance of studying the biogeochemical properties of the building material and the feedback mechanisms between plant and soil prior to finalizing the design of the eco-engineering project.

  5. 2-d and 1-d Nanomaterials Construction through Peptide Computational Design and Solution Assembly

    NASA Astrophysics Data System (ADS)

    Pochan, Darrin

    Self-assembly of molecules is an attractive materials construction strategy due to its simplicity in application. By considering peptidic molecules in the bottom-up materials self-assembly design process, one can take advantage of inherently biomolecular attributes; intramolecular folding events, secondary structure, and electrostatic/H-bonding/hydrophobic interactions to define hierarchical material structure and consequent properties. Importantly, while biomimicry has been a successful strategy for the design of new peptide molecules for intermolecular assembly, computational tools have been developed to de novo design peptide molecules required for construction of pre-determined, desired nanostructures and materials. A new system comprised of coiled coil bundle motifs theoretically designed to assemble into designed, one and two-dimensional nanostructures will be introduced. The strategy provides the opportunity for arbitrary nanostructure formation, i.e. structures not observed in nature, with peptide molecules. Importantly, the desired nanostructure was chosen first while the peptides needed for coiled coil formation and subsequent nanomaterial formation were determined computationally. Different interbundle, two-dimensional nanostructures are stabilized by differences in amino acid composition exposed on the exterior of the coiled coil bundles. Computation was able to determine molecules required for different interbundle symmetries within two-dimensional sheets stabilized by subtle differences in amino acid composition of the inherent peptides. Finally, polymers were also created through covalent interactions between bundles that allowed formation of architectures spanning flexible network forming chains to ultra-stiff polymers, all with the same building block peptides. The success of the computational design strategy is manifested in the nanomaterial results as characterized by electron microscopy, scattering methods, and biophysical techniques. Support from NSF DMREF program under awards DMR-1234161 and DMR-1235084.

  6. 75 FR 54595 - Certain Iron Construction Castings From Brazil, Canada, and the People's Republic of China: Final...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-08

    ...] Certain Iron Construction Castings From Brazil, Canada, and the People's Republic of China: Final Results... construction castings from Brazil, Canada, and the People's Republic of China (PRC), pursuant to section 751(c... antidumping duty orders\\1\\ on certain iron construction castings from Brazil, Canada, and the PRC pursuant to...

  7. Innovative reuse of drinking water sludge in geo-environmental applications.

    PubMed

    Caniani, D; Masi, S; Mancini, I M; Trulli, E

    2013-06-01

    In recent years, the replacement of natural raw materials with new alternative materials, which acquire an economic, energetic and environmental value, has gained increasing importance. The considerable consumption of water has favoured the increase in the number of drinking water treatment plants and, consequently, the production of drinking water sludge. This paper proposes a protocol of analyses capable of evaluating chemical characteristics of drinking water sludge from surface water treatment plants. Thereby we are able to assess their possible beneficial use for geo-environmental applications, such as the construction of barrier layers for landfill and for the formation of "bio-soils", when mixed with the stabilized organic fraction of municipal solid waste. This paper reports the results of a study aimed at evaluating the quality and environmental aspects of reconstructed soils ("bio-soil"), which are used in much greater quantities than the usual standard, for "massive" applications in environmental actions such as the final cover of landfills. The granulometric, chemical and physical analyses of the sludge and the leaching test on the stabilized organic fraction showed the suitability of the proposed materials for reuse. The study proved that the reuse of drinking water sludge for the construction of barrier layers and the formation of "bio-soils" reduces the consumption of natural materials, the demand for landfill volumes, and offers numerous technological advantages. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Comparison of different target material options for the European Spallation Source based on certain aspects related to the final disposal

    NASA Astrophysics Data System (ADS)

    Kókai, Zsófia; Török, Szabina; Zagyvai, Péter; Kiselev, Daniela; Moormann, Rainer; Börcsök, Endre; Zanini, Luca; Takibayev, Alan; Muhrer, Günter; Bevilacqua, Riccardo; Janik, József

    2018-02-01

    Different target options have been examined for the European Spallation Source, which is under construction in Lund, Sweden. During the design update phase, parameters and characteristics for the target design have been optimized not only for neutronics but also with respect to the waste characteristics related to the final disposal of the target. A rotating, solid tungsten target was eventually selected as baseline concept; the other options considered included mercury and lead-bismuth (LBE) targets suitable for a pulsed source. Since the licensee is obliged to present a decommissioning plan even before the construction phase starts, the radioactive waste category of the target after full operation time is of crucial importance. The results obtained from a small survey among project partners of 7th Framework Program granted by EU 202247 contract have been used. Waste characteristics of different potential spallation target materials were compared. Based on waste index, the tungsten target is the best alternative and the second one is the mercury target. However, all alternatives have HLW category after a 10 year cooling. Based on heat generation alone all of the options would be below the HLW limit after this cooling period. The LBE is the least advantageous alternative based on waste index and heat generation comparison. These results can be useful in compiling the licensing documents of the ESS facility as the target alternatives can be compared from various aspects related to their disposal.

  9. Constructing the truth: from 'confusion of tongues' to 'constructions in analysis'.

    PubMed

    Press, Jacques

    2006-04-01

    The author hypothesizes that the papers Freud wrote in the period 1934-9 constitute a final turning point in his work resulting from an attempt to work through, by means of self-analysis, early traumatic elements reactivated by the conditions of his life in the 1930s. The author emphasizes that the ups and downs of Freud's relationship with Sándor Ferenczi and the mourning which followed his death in 1933 played an important role in this traumatic situation. He suggests that through these last works, Freud pursued a posthumous dialogue with Ferenczi. This working through led Freud, in Moses and monotheism, to an ultimate revision of his theory of trauma, a revision which the author examines in full, in the light of the works of the Egyptologist, Jan Assmann. A new analytical paradigm emerges: that of constructions in analysis developed in the article of the same name. The activity of construction appears as an alternative to the mutual analysis proposed by Ferenczi and is closely bound up with the notion of historical truth. In psychoanalysis, it would mean constructing a historical truth whose anchoring in the material truth of the past is essential, though it should not be confused with it.

  10. Superfund Record of Decision (EPA Region 5): Bofors Nobel Site, Muskegon, MI. (First remedial action), (amendment), July 1992. Final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    The 85-acre Bofors Nobel site contains an active specialty chemical production plant in Egelston Township, Muskegon County, Michigan. Site features include an unused landfill. The ROD amends a 1990 ROD written by the state, which consisted of onsite incineration and onsite landfilling of lagoon area soil, construction of RCRA-type secure landfill cells to hold non-incinerated material and ash from the incinerated sludge. The selected amended remedial action for the site includes excavating and containing approximately 767,000 cubic yards of untreated sludge and soil in onsite RCRA-type secure landfill cells constructed as part of the original remedial action. The ROD Amendmentmore » does not address any issue associated with ground water treatment.« less

  11. INNOVATIVE FOSSIL FUEL FIRED VITRIFICATION TECHNOLOGY FOR SOIL REMEDIATION

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    J. Hnat; L.M. Bartone; M. Pineda

    2001-07-13

    This Summary Report summarizes the progress of Phases 3, 3A and 4 of a waste technology Demonstration Project sponsored under a DOE Environmental Management Research and Development Program and administered by the U.S. Department of Energy National Energy Technology Laboratory-Morgantown (DOE-NETL) for an ''Innovative Fossil Fuel Fired Vitrification Technology for Soil Remediation''. The Summary Reports for Phases 1 and 2 of the Program were previously submitted to DOE. The total scope of Phase 3 was to have included the design, construction and demonstration of Vortec's integrated waste pretreatment and vitrification process for the treatment of low level waste (LLW), TSCA/LLWmore » and mixed low-level waste (MLLW). Due to funding limitations and delays in the project resulting from a law suit filed by an environmental activist and the extended time for DOE to complete an Environmental Assessment for the project, the scope of the project was reduced to completing the design, construction and testing of the front end of the process which consists of the Material Handling and Waste Conditioning (MH/C) Subsystem of the vitrification plant. Activities completed under Phases 3A and 4 addressed completion of the engineering, design and documentation of the Material Handling and Conditioning System such that final procurement of the remaining process assemblies can be completed and construction of a Limited Demonstration Project be initiated in the event DOE elects to proceed with the construction and demonstration testing of the MH/C Subsystem.« less

  12. Large-Scale Fabrication of Silicon Nanowires for Solar Energy Applications.

    PubMed

    Zhang, Bingchang; Jie, Jiansheng; Zhang, Xiujuan; Ou, Xuemei; Zhang, Xiaohong

    2017-10-11

    The development of silicon (Si) materials during past decades has boosted up the prosperity of the modern semiconductor industry. In comparison with the bulk-Si materials, Si nanowires (SiNWs) possess superior structural, optical, and electrical properties and have attracted increasing attention in solar energy applications. To achieve the practical applications of SiNWs, both large-scale synthesis of SiNWs at low cost and rational design of energy conversion devices with high efficiency are the prerequisite. This review focuses on the recent progresses in large-scale production of SiNWs, as well as the construction of high-efficiency SiNW-based solar energy conversion devices, including photovoltaic devices and photo-electrochemical cells. Finally, the outlook and challenges in this emerging field are presented.

  13. Life cycle assessment of construction and demolition waste management.

    PubMed

    Butera, Stefania; Christensen, Thomas H; Astrup, Thomas F

    2015-10-01

    Life cycle assessment (LCA) modelling of construction and demolition waste (C&DW) management was carried out. The functional unit was management of 1 Mg mineral, source separated C&DW, which is either utilised in road construction as a substitute for natural aggregates, or landfilled. The assessed environmental impacts included both non-toxic and toxic impact categories. The scenarios comprised all stages of the end-of-life management of C&DW, until final disposal of all residues. Leaching of inorganic contaminants was included, as was the production of natural aggregates, which was avoided because of the use of C&DW. Typical uncertainties related to contaminant leaching were addressed. For most impact categories, utilisation of C&DW in road construction was preferable to landfilling; however, for most categories, utilisation resulted in net environmental burdens. Transportation represented the most important contribution for most nontoxic impacts, accounting for 60-95 per cent of these impacts. Capital goods contributed with negligible impacts. Leaching played a critical role for the toxic categories, where landfilling had lower impacts than utilisation because of the lower levels of leachate per ton of C&DW reaching the groundwater over a 100-year perspective. Leaching of oxyanions (As, V and Sb) was critical with respect to leaching. Typical experimental uncertainties in leaching data did not have a pivotal influence on the results; however, accounting for Cr immobilisation in soils as part of the impact assessment was critical for modelling the leaching impacts. Compared with the overall life cycle of building and construction materials, leaching emissions were shown to be potentially significant for toxicity impacts, compared with contributions from production of the same materials, showing that end-of-life impacts and leaching should not be disregarded when assessing environmental impacts from construction products and materials. CO2 uptake in the C&DW corresponding to 15 per cent carbonation could out-balance global warming impacts from transportation; however, carbonation would also likely result in increased toxicity impacts due to higher leaching of oxyanions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Thermophysical properties of hydrophobised lime plasters - The influence of ageing

    NASA Astrophysics Data System (ADS)

    Pavlíková, Milena; Zemanová, Lucie; Pavlík, Zbyšek

    2017-07-01

    The building envelope is a principal responsible for buildings energy loses. Lime plasters as the most popular finishing materials of historical buildings and culture monuments influence the thermal behaviour as well as construction material of masonry. On this account, the effect of ageing on the thermophysical properties of a newly designed lime plasters containing hydrophobic admixture is analysed in the paper. For the comparative purposes, the reference lime plaster is tested. The ageing is accelerated with controlled carbonation process to simulate the final plasters properties. Basic characterization of the tested materials is done using bulk density, matrix density, and porosity measurements. Thermal conductivity and volumetric heat capacity are experimentally assessed using a transient impulse method. The obtained data revealed the significant changes of the both studied thermal parameters in the dependence on plasters composition and age. The assessed material parameters will be stored in a material database, where will find use as an input data for computational modelling of heat transport in this type of porous building materials and evaluation of energy-savings and sustainability issues.

  15. Recycling

    NASA Astrophysics Data System (ADS)

    Goto, Junya; Santorelli, Michael

    Recycling systems are classified into those employing typically three methods, and the progress of each method is described. In mechanical recycling, powders of phenolic materials are recovered via a mechanical process and reused as fillers or additives in virgin materials. The effects to flowability, curability, and mechanical properties of the materials are explained. In feedstock recycling, monomers, oligomers, or oils are recovered via chemical processes and reused as feedstock. Pyrolysis, solvolysis or hydrolysis, and supercritical or subcritical fluid technology will also be introduced. When using a subcritical fluid of phenol, the recycled material maintains excellent properties similar to the virgin material, and a demonstration plant has been constructed to carry out mass production development. In energy recovery, wastes of phenolic materials are used as an alternative solid fuel to coal because they are combustible and have good calorific value. Industrial wastes of these have been in practical use in a cement plant. Finally, it is suggested that the best recycling method should be selected according to the purpose or situation, because every recycling method has both strengths and weaknesses. Therefore, quantitative and objective evaluation methods in recycling are desirable and should be established.

  16. Solidification/stabilization of chromite ore processing residue using alkali-activated composite cementitious materials.

    PubMed

    Huang, Xiao; Zhuang, RanLiang; Muhammad, Faheem; Yu, Lin; Shiau, YanChyuan; Li, Dongwei

    2017-02-01

    Chromite Ore Processing Residue (COPR) produced in chromium salt production process causes a great health and environmental risk with Cr(VI) leaching. The solidification/stabilization (S/S) of COPR using alkali-activated blast furnace slag (BFS) and fly ash (FA) based cementitious material was investigated in this study. The optimum percentage of BFS and FA for preparing the alkali-activated BFS-FA binder had been studied. COPR was used to replace the amount of BFS-FA or ordinary Portland cement (OPC) for the preparation of the cementitious materials, respectively. The immobilization effect of the alkali-activated BFS-FA binder on COPR was much better than that of OPC based cementitious material. The potential for reusing the final treatment product as a readily available construction material was evaluated. X-ray diffraction (XRD), Fourier transform infrared spectrometry (FTIR) and scanning electron microscope with energy dispersive spectrometer (SEM-EDS) analysis indicated that COPR had been effectively immobilized. The solidification mechanism is the combined effect of reduction, ion exchange, precipitation, adsorption and physical fixation in the alkali-activated composite cementitious material. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Biochemistry-directed hollow porous microspheres: bottom-up self-assembled polyanion-based cathodes for sodium ion batteries

    NASA Astrophysics Data System (ADS)

    Lin, Bo; Li, Qiufeng; Liu, Baodong; Zhang, Sen; Deng, Chao

    2016-04-01

    Biochemistry-directed synthesis of functional nanomaterials has attracted great interest in energy storage, catalysis and other applications. The unique ability of biological systems to guide molecule self-assembling facilitates the construction of distinctive architectures with desirable physicochemical characteristics. Herein, we report a biochemistry-directed ``bottom-up'' approach to construct hollow porous microspheres of polyanion materials for sodium ion batteries. Two kinds of polyanions, i.e. Na3V2(PO4)3 and Na3.12Fe2.44(P2O7)2, are employed as cases in this study. The microalgae cell realizes the formation of a spherical ``bottom'' bio-precursor. Its tiny core is subjected to destruction and its tough shell tends to carbonize upon calcination, resulting in the hollow porous microspheres for the ``top'' product. The nanoscale crystals of the polyanion materials are tightly enwrapped by the highly-conductive framework in the hollow microsphere, resulting in the hierarchical nano-microstructure. The whole formation process is disclosed as a ``bottom-up'' mechanism. Moreover, the biochemistry-directed self-assembly process is confirmed to play a crucial role in the construction of the final architecture. Taking advantage of the well-defined hollow-microsphere architecture, the abundant interior voids and the highly-conductive framework, polyanion materials show favourable sodium-intercalation kinetics. Both materials are capable of high-rate long-term cycling. After five hundred cycles at 20 C and 10 C, Na3V2(PO4)3 and Na3.12Fe2.44(P2O7)2 retain 96.2% and 93.1% of the initial capacity, respectively. Therefore, the biochemistry-directed technique provides a low-cost, highly-efficient and widely applicable strategy to produce high-performance polyanion-based cathodes for sodium ion batteries.Biochemistry-directed synthesis of functional nanomaterials has attracted great interest in energy storage, catalysis and other applications. The unique ability of biological systems to guide molecule self-assembling facilitates the construction of distinctive architectures with desirable physicochemical characteristics. Herein, we report a biochemistry-directed ``bottom-up'' approach to construct hollow porous microspheres of polyanion materials for sodium ion batteries. Two kinds of polyanions, i.e. Na3V2(PO4)3 and Na3.12Fe2.44(P2O7)2, are employed as cases in this study. The microalgae cell realizes the formation of a spherical ``bottom'' bio-precursor. Its tiny core is subjected to destruction and its tough shell tends to carbonize upon calcination, resulting in the hollow porous microspheres for the ``top'' product. The nanoscale crystals of the polyanion materials are tightly enwrapped by the highly-conductive framework in the hollow microsphere, resulting in the hierarchical nano-microstructure. The whole formation process is disclosed as a ``bottom-up'' mechanism. Moreover, the biochemistry-directed self-assembly process is confirmed to play a crucial role in the construction of the final architecture. Taking advantage of the well-defined hollow-microsphere architecture, the abundant interior voids and the highly-conductive framework, polyanion materials show favourable sodium-intercalation kinetics. Both materials are capable of high-rate long-term cycling. After five hundred cycles at 20 C and 10 C, Na3V2(PO4)3 and Na3.12Fe2.44(P2O7)2 retain 96.2% and 93.1% of the initial capacity, respectively. Therefore, the biochemistry-directed technique provides a low-cost, highly-efficient and widely applicable strategy to produce high-performance polyanion-based cathodes for sodium ion batteries. Electronic supplementary information (ESI) available: Synthesis, morphology and physical characteristics of reference samples; pore size distribution of the hollow porous microsphere; morphology of the bio-directed Na3.12Fe2.44(P2O7)2 hollow microsphere; comparison of the Rct values for the Na3.12Fe2.44(P2O7)2 composites; TEM images of the cycled materials; lattice parameters and atomic ratio of the samples; calculation process of sodium intercalation coefficients based on the GITT results. See DOI: 10.1039/c6nr00680a

  18. Engineering behavior of small-scale foundation piers constructed from alternative materials

    NASA Astrophysics Data System (ADS)

    Prokudin, Maxim Mikhaylovich

    Testing small-scale prototype pier foundations to evaluate engineering behavior is an alternative to full-scale testing that facilitates testing of several piers and pier groups at relatively low cost. In this study, various pier systems and pier groups at one tenth scale were subjected to static vertical loading under controlled conditions to evaluate stiffness, bearing capacity, and group efficiency. Pier length, material properties and methods of installation were evaluated. Pier length to diameter ratios varied between four and eight. A unique soil pit with dimensions of 2.1 m in width, 1.5 m in length and 2.0 m in depth was designed to carry out this research. The test pit was filled with moisture conditioned and compacted Western Iowa loess. A special load test frame was designed and fabricated to provide up to 25,000 kg vertical reaction force for load testing. A load cell and displacement instrumentation was setup to capture the load test data. Alternative materials to conventional cement concrete were studied. The pier materials evaluated in this study included compacted aggregate, cement stabilized silt, cementitious grouts, and fiber reinforced silt. Key findings from this study demonstrated that (1) the construction method influences the behavior of aggregate piers, (2) the composition of the pier has a significant impact on the stiffness, (3) group efficiencies were found to be a function of pier length and pier material, (4) in comparison to full-scale testing the scaled piers were found to produce a stiffer response with load-settlement and bearing capacities to be similar. Further, although full-scale test results were not available for all pier materials, the small-scale testing provided a means for comparing results between pier systems. Finally, duplicate pier tests for a given length and material were found to be repeatable.

  19. 46 CFR 58.05-1 - Material, design and construction.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... AUXILIARY MACHINERY AND RELATED SYSTEMS Main Propulsion Machinery § 58.05-1 Material, design and construction. (a) The material, design, construction, workmanship, and arrangement of main propulsion machinery...

  20. 46 CFR 58.05-1 - Material, design and construction.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... AUXILIARY MACHINERY AND RELATED SYSTEMS Main Propulsion Machinery § 58.05-1 Material, design and construction. (a) The material, design, construction, workmanship, and arrangement of main propulsion machinery...

  1. 46 CFR 58.05-1 - Material, design and construction.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... AUXILIARY MACHINERY AND RELATED SYSTEMS Main Propulsion Machinery § 58.05-1 Material, design and construction. (a) The material, design, construction, workmanship, and arrangement of main propulsion machinery...

  2. 46 CFR 58.05-1 - Material, design and construction.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... AUXILIARY MACHINERY AND RELATED SYSTEMS Main Propulsion Machinery § 58.05-1 Material, design and construction. (a) The material, design, construction, workmanship, and arrangement of main propulsion machinery...

  3. 46 CFR 58.05-1 - Material, design and construction.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... AUXILIARY MACHINERY AND RELATED SYSTEMS Main Propulsion Machinery § 58.05-1 Material, design and construction. (a) The material, design, construction, workmanship, and arrangement of main propulsion machinery...

  4. Construction demolition wastes, Waelz slag and MSWI bottom ash: a comparative technical analysis as material for road construction.

    PubMed

    Vegas, I; Ibañez, J A; San José, J T; Urzelai, A

    2008-01-01

    The objective of the study is to analyze the technical suitability of using secondary materials from three waste flows (construction and demolition waste (CDW), Waelz slag and municipal solid waste incineration (MSWI) bottom ash), under the regulations and standards governing the use of materials for road construction. A detailed technical characterization of the materials was carried out according to Spanish General Technical Specifications for Road Construction (PG3). The results show that Waelz slag can be adequate for using in granular structural layers, while CDW fits better as granular material in roadbeds. Likewise, fresh MSWI bottom ash can be used as roadbed material as long as it does not contain a high concentration of soluble salts. This paper also discusses the adequacy of using certain traditional test methods for natural soils when characterizing secondary materials for use as aggregates in road construction.

  5. Evaluation of Bluetooth communications for the deployment of assisted living technologies in home environments.

    PubMed

    McGrath, Michael J; Burns, Adrian; Dishongh, Terry

    2007-01-01

    Using five different commercially available class one and class two Bluetooth dongles a total of seven homes which represented a cross section of typical Irish homes were surveyed to determine the effect of construction methods, house size, sensor placement, host placement, antenna design and RF interference had on the link quality of Bluetooth enabled sensors. The results obtained indicates there is high variability in the link quality which is determined by the quality of the BT radio, placement of the antenna on both the master and slave, the number of walls which must be penetrated and the construction materials used in the wall. The placement of the sensor was the single biggest factor in determining the link quality. The type of construction used in the interior walls has significant influence also. The final factor of significant influence was the type of antenna used on the Bluetooth dongle. The use of an external antenna gave significantly better range performance than an internal antenna.

  6. Three Dimensional Analysis of the Final Design of Pier Extensions and West Guide Wall to Mitigate Local Scour Risk at the BNSF Railroad Bridge Downstream of the Prado Dam Supplemental Report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lottes, S. A.; Sinha, N.; Bojanowski, C.

    This report is a supplement to a previous report [ref] covering optimization of wedge shaped pier extensions to streamline large bluff body piers as a local scour countermeasure for the Burlington Northern and Santa Fe (BNSF) Railroad Bridge over the Santa Ana River downstream of Prado Dam in Riverside County, CA. The optimized design was tested in a 1/30 scale physical model at U.S. Army Engineer Research and Development Center (ERDC) in Vicksburg, MS, and the optimized design was used as the base for the construction design. Constructability issues having to do with both materials and site conditions including accessmore » underneath the BNSF bridge yielded a construction design that required making the pier extensions wider and either moving the western curve of the west guide wall upstream or changing its geometry.« less

  7. Design and Installation of a Disposal Cell Cover Field Test

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Benson, C.H.; Waugh, W.J.; Albright, W.H.

    2011-02-27

    The U.S. Department of Energy’s Office of Legacy Management (LM) initiated a cover assessment project in September 2007 to evaluate an inexpensive approach to enhancing the hydrological performance of final covers for disposal cells. The objective is to accelerate and enhance natural processes that are transforming existing conventional covers, which rely on low-conductivity earthen barriers, into water balance covers, that store water in soil and release it as soil evaporation and plant transpiration. A low conductivity cover could be modified by deliberately blending the upper layers of the cover profile and planting native shrubs. A test facility was constructed atmore » the Grand Junction, Colorado, Disposal Site to evaluate the proposed methodology. The test cover was constructed in two identical sections, each including a large drainage lysimeter. The test cover was constructed with the same design and using the same materials as the existing disposal cell in order to allow for a direct comparison of performance. One test section will be renovated using the proposed method; the other is a control. LM is using the lysimeters to evaluate the effectiveness of the renovation treatment by monitoring hydrologic conditions within the cover profile as well as all water entering and leaving the system. This paper describes the historical experience of final covers employing earthen barrier layers, the design and operation of the lysimeter test facility, testing conducted to characterize the as-built engineering and edaphic properties of the lysimeter soils, the calibration of instruments installed at the test facility, and monitoring data collected since the lysimeters were constructed.« less

  8. 77 FR 49722 - Cranes and Derricks in Construction: Demolition and Underground Construction

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-17

    ... cranes rule, OSHA prepared a final economic analysis (FEA) as required by the Occupational Safety and... construction work involving demolition. The FEA for the final cranes standard, which included all cranes, crane... were technologically and economically feasible. Because the FEA drew these conclusions from...

  9. 78 FR 22031 - California High-Speed Rail Authority-Construction Exemption-In Merced, Madera and Fresno Counties...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-12

    ... High-Speed Rail Authority--Construction Exemption--In Merced, Madera and Fresno Counties, CA AGENCY... High-Speed Rail Authority (Authority). This Final EIS is titled ``California High-Speed Train: Merced... Final EIS assesses the potential environmental impacts of constructing and operating a high-speed...

  10. Final Environmental Assessment for Wide Area Coverage Construct Land Mobile Network Communications Infrastructure Malmstrom Air Force Base, Montana

    DTIC Science & Technology

    2008-02-01

    FINAL ENVIRONMENTAL ASSESSMENT February 2008 Malmstrom ® AFB WIDE AREA COVERAGE CONSTRUCT LAND MOBILE NETWORK COMMUNICATIONS INFRASTRUCTURE...Wide Area Coverage Construct Land Mobile Network Communications Infrastructure Malmstrom Air Force Base, Montana 5a. CONTRACT NUMBER 5b. GRANT...SIGNIFICANT IMPACT WIDE AREA COVERAGE CONSTRUCT LAND MOBILE NETWORK COMMUNICATIONS INFRASTRUCTURE MALMSTROM AIR FORCE BASE, MONTANA The

  11. An improved computational approach for multilevel optimum design

    NASA Technical Reports Server (NTRS)

    Haftka, R. T.

    1984-01-01

    A penalty-function algorithm employing Newton's method with approximate second derivatives (Haftka and Starnes, 1980) is developed for two-level hierarchical design optimization problems. The difficulties posed by discontinuous behavior in typical multilevel problems are explained and illustrated for the case of a three-bar truss; the algorithm is formulated; and its advantages are demonstrated in the problem of a portal framework having three beams (described by six cross-section parameters), subjected to two loading conditions, and to be constructed in six different materials for comparison. The final design parameters are listed in a table.

  12. Final Environmental Assessment for the Proposed Construction and Operation of a Live Fire-Fighting Training Area at Buckley Air Force Base, Colorado

    DTIC Science & Technology

    2004-06-01

    No. 950PAR118. This permit was originally issued on 28 August 1997, most recently reissued as of 01 July 2002, and expires 30 June 2007 (BAFB 2001...In July 2002, the CDPHE performed an inspection of stationary source emission units and determined that BAFB was in compliance with the Title V...during the winter, spring, and fall to 9.8 million gallons for the summer months, such as July . 3.11 HAZARDOUS MATERIALS AND SUBSTANCES The ROI for

  13. Mixtures of beta distributions in models of the duration of a project affected by risk

    NASA Astrophysics Data System (ADS)

    Gładysz, Barbara; Kuchta, Dorota

    2017-07-01

    This article presents a method for timetabling a project affected by risk. The times required to carry out tasks are modelled using mixtures of beta distributions. The parameters of these beta distributions are given by experts: one corresponding to the duration of a task in stable conditions, with no risks materializing, and the other corresponding to the duration of a task in the case when risks do occur. Finally, a case study will be presented and analysed: the project of constructing a shopping mall in Poland.

  14. Porous silicon in drug delivery devices and materials☆

    PubMed Central

    Anglin, Emily J.; Cheng, Lingyun; Freeman, William R.; Sailor, Michael J.

    2009-01-01

    Porous Si exhibits a number of properties that make it an attractive material for controlled drug delivery applications: The electrochemical synthesis allows construction of tailored pore sizes and volumes that are controllable from the scale of microns to nanometers; a number of convenient chemistries exist for the modification of porous Si surfaces that can be used to control the amount, identity, and in vivo release rate of drug payloads and the resorption rate of the porous host matrix; the material can be used as a template for organic and biopolymers, to prepare composites with a designed nanostructure; and finally, the optical properties of photonic structures prepared from this material provide a self-reporting feature that can be monitored in vivo. This paper reviews the preparation, chemistry, and properties of electrochemically prepared porous Si or SiO2 hosts relevant to drug delivery applications. PMID:18508154

  15. Wide band design on the scaled absorbing material filled with flaky CIPs

    NASA Astrophysics Data System (ADS)

    Xu, Yonggang; Yuan, Liming; Gao, Wei; Wang, Xiaobing; Liang, Zichang; Liao, Yi

    2018-02-01

    The scaled target measurement is an important method to get the target characteristic. Radar absorbing materials are widely used in the low detectable target, considering the absorbing material frequency dispersion characteristics, it makes designing and manufacturing scaled radar absorbing materials on the scaled target very difficult. This paper proposed a wide band design method on the scaled absorbing material of the thin absorption coating with added carbonyl iron particles. According to the theoretical radar cross section (RCS) of the plate, the reflection loss determined by the permittivity and permeability was chosen as the main design factor. Then, the parameters of the scaled absorbing materials were designed using the effective medium theory, and the scaled absorbing material was constructed. Finally, the full-size coating plate and scaled coating plates (under three different scale factors) were simulated; the RCSs of the coating plates were numerically calculated and measured at 4 GHz and a scale factor of 2. The results showed that the compensated RCS of the scaled coating plate was close to that of the full-size coating plate, that is, the mean deviation was less than 0.5 dB, and the design method for the scaled material was very effective.

  16. 46 CFR 32.60-1 - Scantlings, material, and workmanship-TB/ALL.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... § 32.60-1 Scantlings, material, and workmanship—TB/ALL. (a) All tank vessels, the construction or... construction of hulls. The hull and deckhouses shall be of steel or iron construction except that the pilothouse and decks over quarters may be constructed of wood. Scantlings, material, and workmanship...

  17. 48 CFR 52.225-10 - Notice of Buy American Act Requirement-Construction Materials.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... the requirements of the Buy American Act, based on claimed unreasonable cost of domestic construction... Requirement-Construction Materials. 52.225-10 Section 52.225-10 Federal Acquisition Regulations System FEDERAL... Provisions and Clauses 52.225-10 Notice of Buy American Act Requirement—Construction Materials. As prescribed...

  18. 48 CFR 52.225-10 - Notice of Buy American Act Requirement-Construction Materials.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... the requirements of the Buy American Act, based on claimed unreasonable cost of domestic construction... Requirement-Construction Materials. 52.225-10 Section 52.225-10 Federal Acquisition Regulations System FEDERAL... Provisions and Clauses 52.225-10 Notice of Buy American Act Requirement—Construction Materials. As prescribed...

  19. 48 CFR 52.225-10 - Notice of Buy American Requirement-Construction Materials.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Requirement-Construction Materials. 52.225-10 Section 52.225-10 Federal Acquisition Regulations System FEDERAL... Provisions and Clauses 52.225-10 Notice of Buy American Requirement—Construction Materials. As prescribed in 25.1102(b)(1), insert the following provision: Notice of Buy American Requirement—Construction...

  20. 48 CFR 52.225-12 - Notice of Buy American Requirement-Construction Materials Under Trade Agreements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Requirement-Construction Materials Under Trade Agreements. 52.225-12 Section 52.225-12 Federal Acquisition... CONTRACT CLAUSES Text of Provisions and Clauses 52.225-12 Notice of Buy American Requirement—Construction... Buy American Requirement—Construction Materials Under Trade Agreements (MAY 2014) (a) Definitions...

  1. 48 CFR 52.225-10 - Notice of Buy American Act Requirement-Construction Materials.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... the requirements of the Buy American Act, based on claimed unreasonable cost of domestic construction... Requirement-Construction Materials. 52.225-10 Section 52.225-10 Federal Acquisition Regulations System FEDERAL... Provisions and Clauses 52.225-10 Notice of Buy American Act Requirement—Construction Materials. As prescribed...

  2. 48 CFR 52.225-10 - Notice of Buy American Act Requirement-Construction Materials.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... the requirements of the Buy American Act, based on claimed unreasonable cost of domestic construction... Requirement-Construction Materials. 52.225-10 Section 52.225-10 Federal Acquisition Regulations System FEDERAL... Provisions and Clauses 52.225-10 Notice of Buy American Act Requirement—Construction Materials. As prescribed...

  3. Mass of materials: the impact of designers on construction ergonomics.

    PubMed

    Smallwood, John

    2012-01-01

    Many construction injuries are musculoskeletal related in the form of sprains and strains arising from the handling of materials, which are specified by designers. The paper presents the results of a study conducted among delegates attending two 'designing for H&S' (DfH&S) seminars using a questionnaire. The salient findings include: the level of knowledge relative to the mass and density of materials is limited; designers generally do not consider the mass and density of materials when designing structures and elements and specifying materials; to a degree designers appreciate that the mass and density of materials impact on construction ergonomics; designers rate their knowledge of the mass and density of materials as limited, and designers appreciate the potential of the consideration of the mass and density of materials to contribute to an improvement in construction ergonomics. Conclusions include: designers lack the requisite knowledge relative to the mass and density of materials; designers are thus precluded from conducting optimum design hazard identification and risk assessments, and tertiary built environment designer education does not enlighten designers relative to construction ergonomics. Recommendations include: tertiary built environment designer education should construction ergonomics; professional associations should raise the level of awareness relative to construction ergonomics, and design practices should include a category 'mass and density of materials' in their practice libraries.

  4. 46 CFR 160.054-3 - Construction.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 6 2012-10-01 2012-10-01 false Construction. 160.054-3 Section 160.054-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS... Construction. (a) Construction. The container shall be constructed of tough transparent material, not less than...

  5. 46 CFR 160.054-3 - Construction.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 6 2014-10-01 2014-10-01 false Construction. 160.054-3 Section 160.054-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS... Construction. (a) Construction. The container shall be constructed of tough transparent material, not less than...

  6. 46 CFR 160.054-3 - Construction.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 6 2011-10-01 2011-10-01 false Construction. 160.054-3 Section 160.054-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS... Construction. (a) Construction. The container shall be constructed of tough transparent material, not less than...

  7. 46 CFR 160.054-3 - Construction.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 6 2013-10-01 2013-10-01 false Construction. 160.054-3 Section 160.054-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS... Construction. (a) Construction. The container shall be constructed of tough transparent material, not less than...

  8. Two-dimensional heterostructures for energy storage

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gogotsi, Yury G.; Pomerantseva, Ekaterina

    Two-dimensional (2D) materials provide slit-shaped ion diffusion channels that enable fast movement of lithium and other ions. However, electronic conductivity, the number of intercalation sites, and stability during extended cycling are also crucial for building high-performance energy storage devices. While individual 2D materials, such as graphene, show some of the required properties, none of them can offer all properties needed to maximize energy density, power density, and cycle life. Here we argue that stacking different 2D materials into heterostructured architectures opens an opportunity to construct electrodes that would combine the advantages of the individual building blocks while eliminating the associatedmore » shortcomings. We discuss characteristics of common 2D materials and provide examples of 2D heterostructured electrodes that showed new phenomena leading to superior electrochemical performance. As a result, we also consider electrode fabrication approaches and finally outline future steps to create 2D heterostructured electrodes that could greatly expand current energy storage technologies.« less

  9. Removal of natural hormones in dairy farm wastewater using reactive and sorptive materials.

    PubMed

    Cai, Kai; Phillips, Debra H; Elliott, Christopher T; Muller, Marc; Scippo, Marie-Louise; Connolly, Lisa

    2013-09-01

    The objective of this study was to examine the oestrogen and androgen hormone removal efficiency of reactive (Connelly zero-valent iron (ZVI), Gotthart Maier ZVI) and sorptive (AquaSorb 101 granular activated carbon (GAC) and OrganoLoc PM-100 organoclay (OC)) materials from HPLC grade water and constructed wetland system (CWS) treated dairy farm wastewater. Batch test studies were performed and hormone concentration analysis carried out using highly sensitive reporter gene assays (RGAs). The results showed that hormonal interaction with these materials is selective for individual classes of hormones. Connelly ZVI and AquaSorb 101 GAC were more efficient in removing testosterone (Te) than 17β-estradiol (E2) and showed faster removal rates of oestrogen and androgen than the other materials. Gotthart Maier ZVI was more efficient in removing E2 than Te. OrganoLoc PM-100 OC achieved the lowest final concentration of E2 equivalent (EEQ) and provided maximum removal of both oestrogens and androgens. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. 48 CFR 852.236-89 - Buy American Act.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...) Notwithstanding a bidder's right to offer identifiable foreign construction material in its bid pursuant to FAR 52... listing of the specific foreign construction material he/she intends to use and a price for said material. Bidders must include bid prices for comparable domestic construction material. If VA determines not to...

  11. Materials for advanced ultrasupercritical steam turbines

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Purgert, Robert; Shingledecker, John; Saha, Deepak

    The U.S. Department of Energy (DOE) and the Ohio Coal Development Office (OCDO) have sponsored a project aimed at identifying, evaluating, and qualifying the materials needed for the construction of the critical components of coal-fired power plants capable of operating at much higher efficiencies than the current generation of supercritical plants. This increased efficiency is expected to be achieved principally through the use of advanced ultrasupercritical (A-USC) steam conditions. A limiting factor in this can be the materials of construction for boilers and for steam turbines. The overall project goal is to assess/develop materials technology that will enable achieving turbinemore » throttle steam conditions of 760°C (1400°F)/35MPa (5000 psi). This final technical report covers the research completed by the General Electric Company (GE) and Electric Power Research Institute (EPRI), with support from Oak Ridge National Laboratory (ORNL) and the National Energy Technology Laboratory (NETL) – Albany Research Center, to develop the A-USC steam turbine materials technology to meet the overall project goals. Specifically, this report summarizes the industrial scale-up and materials property database development for non-welded rotors (disc forgings), buckets (blades), bolting, castings (needed for casing and valve bodies), casting weld repair, and casting to pipe welding. Additionally, the report provides an engineering and economic assessment of an A-USC power plant without and with partial carbon capture and storage. This research project successfully demonstrated the materials technology at a sufficient scale and with corresponding materials property data to enable the design of an A-USC steam turbine. The key accomplishments included the development of a triple-melt and forged Haynes 282 disc for bolted rotor construction, long-term property development for Nimonic 105 for blading and bolting, successful scale-up of Haynes 282 and Nimonic 263 castings using traditional sand foundry practices, and a techno-economic study of an A-USC plant including cost estimates for an A-USC turbine which showed A-USC to be economically attractive for partial carbon and capture compared to today’s USC technology. Based on this successful materials research and a review with U.S. utility stakeholders, a new project to develop a component test facility (ComTest) including the world’s first A-USC turbine has been proposed to continue the technology development.« less

  12. 48 CFR 52.225-12 - Notice of Buy American Act Requirement-Construction Materials Under Trade Agreements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... the requirements of the Buy American Act, based on claimed unreasonable cost of domestic construction... Requirement-Construction Materials Under Trade Agreements. 52.225-12 Section 52.225-12 Federal Acquisition...—Construction Materials Under Trade Agreements. As prescribed in 25.1102(d)(1), insert the following provision...

  13. 48 CFR 52.225-12 - Notice of Buy American Act Requirement-Construction Materials Under Trade Agreements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... the requirements of the Buy American Act, based on claimed unreasonable cost of domestic construction... Requirement-Construction Materials Under Trade Agreements. 52.225-12 Section 52.225-12 Federal Acquisition...—Construction Materials Under Trade Agreements. As prescribed in 25.1102(d)(1), insert the following provision...

  14. 48 CFR 52.225-12 - Notice of Buy American Act Requirement-Construction Materials Under Trade Agreements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... the requirements of the Buy American Act, based on claimed unreasonable cost of domestic construction... Requirement-Construction Materials Under Trade Agreements. 52.225-12 Section 52.225-12 Federal Acquisition...—Construction Materials Under Trade Agreements. As prescribed in 25.1102(d)(1), insert the following provision...

  15. 48 CFR 52.225-12 - Notice of Buy American Act Requirement-Construction Materials Under Trade Agreements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... the requirements of the Buy American Act, based on claimed unreasonable cost of domestic construction... Requirement-Construction Materials Under Trade Agreements. 52.225-12 Section 52.225-12 Federal Acquisition...—Construction Materials Under Trade Agreements. As prescribed in 25.1102(d)(1), insert the following provision...

  16. 75 FR 68429 - Cranes and Derricks in Construction; Approval of Information Collection Requirements

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-08

    .... OSHA-2007-0066] RIN 1218-AC01 Cranes and Derricks in Construction; Approval of Information Collection... requirements. SUMMARY: On August 9, 2010, OSHA published a final rule revising the Cranes and Derricks Standard... necessary to protect employees during the use of cranes and derricks in construction. That final standard...

  17. An efficient algorithm for generating diverse microstructure sets and delineating properties closures

    DOE PAGES

    Johnson, Oliver K.; Kurniawan, Christian

    2018-02-03

    Properties closures delineate the theoretical objective space for materials design problems, allowing designers to make informed trade-offs between competing constraints and target properties. In this paper, we present a new algorithm called hierarchical simplex sampling (HSS) that approximates properties closures more efficiently and faithfully than traditional optimization based approaches. By construction, HSS generates samples of microstructure statistics that span the corresponding microstructure hull. As a result, we also find that HSS can be coupled with synthetic polycrystal generation software to generate diverse sets of microstructures for subsequent mesoscale simulations. Finally, by more broadly sampling the space of possible microstructures, itmore » is anticipated that such diverse microstructure sets will expand our understanding of the influence of microstructure on macroscale effective properties and inform the construction of higher-fidelity mesoscale structure-property models.« less

  18. An efficient algorithm for generating diverse microstructure sets and delineating properties closures

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Johnson, Oliver K.; Kurniawan, Christian

    Properties closures delineate the theoretical objective space for materials design problems, allowing designers to make informed trade-offs between competing constraints and target properties. In this paper, we present a new algorithm called hierarchical simplex sampling (HSS) that approximates properties closures more efficiently and faithfully than traditional optimization based approaches. By construction, HSS generates samples of microstructure statistics that span the corresponding microstructure hull. As a result, we also find that HSS can be coupled with synthetic polycrystal generation software to generate diverse sets of microstructures for subsequent mesoscale simulations. Finally, by more broadly sampling the space of possible microstructures, itmore » is anticipated that such diverse microstructure sets will expand our understanding of the influence of microstructure on macroscale effective properties and inform the construction of higher-fidelity mesoscale structure-property models.« less

  19. Multiscale Modeling of Fracture in an SiO2 Nanorod

    NASA Astrophysics Data System (ADS)

    Mallik, Aditi

    2005-11-01

    The fracture of a 108 particle SiO2 nanorod under uniaxial strain is described using an NDDO quantum mechanics. The stress -- strain curve to failure is calculated as a function of strain rate to show a domain that is independent of strain rate. A pair potential for use in classical MD is constructed such that the elastic portion of the quantum curve is reproduced. However, it is shown that the classical analysis does not describe accurately the large strain behavior and failure. Finally, a composite rod is constructed with a small subsystem described by quantum mechanics and the remainder described by classical MD ^1. The stress -- strain curves for the classical, quantum, and composite rods are compared and contrasted. 1. ``Multiscale Modeling of Materials -- Concepts and Illustration'', A. Mallik, K. Runge, J. Dufty, and H-P Cheng, cond-mat 0507558.

  20. Utilization of inorganic industrial wastes in producing construction ceramics. Review of Russian experience for the years 2000-2015.

    PubMed

    Boltakova, N V; Faseeva, G R; Kabirov, R R; Nafikov, R M; Zakharov, Yu A

    2017-02-01

    This paper analyzes the significant scientific publications worldwide for the last 15years concerning construction ceramics (predominantly brick) made with various inorganic industrial wastes added to the ceramic raw material for the improvement of properties and for eco-friendly disposal. The information gap resulting from the lack of mentions of the Russian publications on this subject in English-language reviews is filled. The paper includes brief summaries of 34 dissertations and 29 patents issued in Russia since 2000. The waste additives described in these summaries are grouped by origin type (mining industry waste, ore enrichment waste, metallurgical waste, sludge, ashes, cullet, large-capacity building wastes and waste from various chemical production processes) with the ceramic mixture compositions, molding and firing conditions, final strength, water absorption and other parameters of the final ceramic samples reported. Russian scientists have expanded the nomenclature of each group of wastes significantly upon addition to the list described in English-language reviews for 2000-2015. References to the recent Russian developments in the field of ecological management in ceramic industry are provided. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. The design and development of a high-throughput magneto-mechanostimulation device for cartilage tissue engineering.

    PubMed

    Brady, Mariea A; Vaze, Reva; Amin, Harsh D; Overby, Darryl R; Ethier, C Ross

    2014-02-01

    To recapitulate the in vivo environment and create neo-organoids that replace lost or damaged tissue requires the engineering of devices, which provide appropriate biophysical cues. To date, bioreactors for cartilage tissue engineering have focused primarily on biomechanical stimulation. There is a significant need for improved devices for articular cartilage tissue engineering capable of simultaneously applying multiple biophysical (electrokinetic and mechanical) stimuli. We have developed a novel high-throughput magneto-mechanostimulation bioreactor, capable of applying static and time-varying magnetic fields, as well as multiple and independently adjustable mechanical loading regimens. The device consists of an array of 18 individual stations, each of which uses contactless magnetic actuation and has an integrated Hall Effect sensing system, enabling the real-time measurements of applied field, force, and construct thickness, and hence, the indirect measurement of construct mechanical properties. Validation tests showed precise measurements of thickness, within 14 μm of gold standard calliper measurements; further, applied force was measured to be within 0.04 N of desired force over a half hour dynamic loading, which was repeatable over a 3-week test period. Finally, construct material properties measured using the bioreactor were not significantly different (p=0.97) from those measured using a standard materials testing machine. We present a new method for articular cartilage-specific bioreactor design, integrating combinatorial magneto-mechanostimulation, which is very attractive from functional and cost viewpoints.

  2. Workshop on Using In Situ Resources for Construction of Planetary Outposts

    NASA Technical Reports Server (NTRS)

    Duke, Michael B. (Editor)

    1998-01-01

    The workshop examined the potential uses of indigenous materials on the Moon and Mars, other than those associated with the production of propellants for space transportation. The papers presented concerned the needs for construction, based on analysis of the current NASA Mars reference Mission and past studies studies of lunar outposts; the availability of materials on the Moon and Mars; construction techniques that make use of the natural environment; materials production and fabrication techniques based on indigenous materials; and new technologies that could promote the use of indigenous materials in construction.

  3. Hierarchy concepts: classification and preparation strategies for zeolite containing materials with hierarchical porosity.

    PubMed

    Schwieger, Wilhelm; Machoke, Albert Gonche; Weissenberger, Tobias; Inayat, Amer; Selvam, Thangaraj; Klumpp, Michael; Inayat, Alexandra

    2016-06-13

    'Hierarchy' is a property which can be attributed to a manifold of different immaterial systems, such as ideas, items and organisations or material ones like biological systems within living organisms or artificial, man-made constructions. The property 'hierarchy' is mainly characterised by a certain ordering of individual elements relative to each other, often in combination with a certain degree of branching. Especially mass-flow related systems in the natural environment feature special hierarchically branched patterns. This review is a survey into the world of hierarchical systems with special focus on hierarchically porous zeolite materials. A classification of hierarchical porosity is proposed based on the flow distribution pattern within the respective pore systems. In addition, this review might serve as a toolbox providing several synthetic and post-synthetic strategies to prepare zeolitic or zeolite containing material with tailored hierarchical porosity. Very often, such strategies with their underlying principles were developed for improving the performance of the final materials in different technical applications like adsorptive or catalytic processes. In the present review, besides on the hierarchically porous all-zeolite material, special focus is laid on the preparation of zeolitic composite materials with hierarchical porosity capable to face the demands of industrial application.

  4. Decommissioning a phosphoric acid production plant: a radiological protection case study.

    PubMed

    Stamatis, V; Seferlis, S; Kamenopoulou, V; Potiriadis, C; Koukouliou, V; Kehagia, K; Dagli, C; Georgiadis, S; Camarinopoulos, L

    2010-12-01

    During a preliminary survey at the area of an abandoned fertilizer plant, increased levels of radioactivity were measured at places, buildings, constructions and materials. The extent of the contamination was determined and the affected areas were characterized as controlled areas. After the quantitative and qualitative determination of the contaminated materials, the decontamination was planned and performed step by step: the contaminated materials were categorized according to their physical characteristics (scrap metals, plastic pipes, scales and residues, building materials, etc) and according to their level of radioactivity. Depending on the material type, different decontamination and disposal options were proposed; the most appropriate technique was chosen taking into account apart from technical issues, the legal framework, radiation protection issues, the opinion of the local authorities involved as well as the owner's wish. After taking away the biggest amount of the contaminated materials, an iterative process consisting of surveys and decontamination actions was performed in order to remove the residual traces of contamination from the area. During the final survey, no residual surface contamination was detected; some sparsely distributed low level contaminated materials deeply immersed into the soil were found and removed. Copyright © 2010 Elsevier Ltd. All rights reserved.

  5. Does information overload prevent chronic patients from reading self-management educational materials?

    PubMed

    Liu, Chung-Feng; Kuo, Kuang-Ming

    2016-05-01

    Self-care management is becoming an important part of care for chronic patients. However, various kinds of self-management educational materials which government or healthcare institutions provide for patients may not achieve the expected outcome. One of the critical reasons affecting patients' use intention could be patients' perceived information overload regarding the self-management educational materials. This study proposed an extended model of the Theory of Planned Behavior (TPB), which incorporated perceived information overload, to explore if information overload will prevent chronic patients from reading educational materials for self-care management. The independent variables are attitude, subject norm, perceived behavior control and perceived information overload while the dependent variable is behavior intention to use the self-management educational materials. Perceived information overload is also referred to as an antecedent variable which may has impacts on attitude and perceived behavior control. The cross-sectional study interviewed newly diagnosed chronic patients with coronary artery disease, who are the potential users of the self-management educational materials, in a medical center in Taiwan. Data were analyzed using descriptive statistics of the basic information distribution of the respondents, and structural equation modeling to study the reliability and validity for testing hypotheses. A total of 110 respondents were enrolled in this study and successful interview data were collected from 106 respondents. The result indicates that the patients' perceived information overload of self-management educational materials was validated to have impacts on attitude and perceived behavioral control constructs of the TPB as well as contributing a direct impact on patients' intentions to use self-management educational materials. Besides, subjective norm and perceived behavioral control constructs were validated to have significant impacts on behavioral intentions, whereas the attitude construct was not. Finally, the relationships between information overload and attitude, information overload and intention, subjective norm and intention, as well as perceived behavioral control and intention varied significantly between highly- and less-educated respondents. Differing self-management educational materials for respondents of various educational levels could be formulated to substantially boost the use of self-management educational materials. This study demonstrated a comprehensive framework, which extended perceived information overload into the TPB model, to predict patients' behavioral intention of using self-management educational materials. We expect the results of this study will provide useful insights for studying self-management educational materials usage and information overload from the perspectives of academia, governments, and healthcare providers. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  6. Analysis of effective thermal conductivity of fibrous materials

    NASA Technical Reports Server (NTRS)

    Futschik, Michael W.; Witte, Larry C.

    1993-01-01

    The objective of this research is to gain a better understanding of the various mechanisms of heat transfer through fibrous materials and to gain insight into how fill-gas pressure influences the effective thermal conductivity. By way of first principles and some empiricism, two mathematical models are constructed to correlate experimental data. The data are obtained from a test series measuring the effective thermal conductivity of Nomex using a two-sided guarded hot-plate heater apparatus. Tests are conducted for certain mean temperatures and fill-gases over a range of pressures varying from vacuum to atmospheric conditions. The models are then evaluated to determine their effectiveness in representing the effective thermal conductivity of a fibrous material. The models presented herein predict the effective thermal conductivity of Nomex extremely well. Since the influence of gas conduction is determined to be the most influential component in predicting the effective thermal conductivity of a fibrous material, an improved representation of gas conduction is developed. Finally, some recommendations for extension to other random-oriented fiber materials are made concerning the usefulness of each model depending on their advantages and disadvantages.

  7. Testing fireproof materials in a combustion chamber

    NASA Astrophysics Data System (ADS)

    Kulhavy, Petr; Martinec, Tomas; Novak, Ondrej; Petru, Michal; Srb, Pavel

    This article deals with a prototype concept, real experiment and numerical simulation of a combustion chamber, designed for testing fire resistance some new insulating composite materials. This concept of a device used for testing various materials, providing possibility of monitoring temperatures during controlled gas combustion. As a fuel for the combustion process propane butane mixture has been used and also several kinds of burners with various conditions of inlet air (forced, free) and fuel flows were tested. The tested samples were layered sandwich materials based on various materials or foams, used as fillers in fire shutters. The temperature distribution was measured by using thermocouples. A simulation of whole concept of experimental chamber has been carried out as the non-premixed combustion process in the commercial final volume sw Pyrosim. The result was to design chamber with a construction suitable, according to the international standards, achieve the required values (temperature in time). Model of the combustion based on a stoichiometric defined mixture of gas and the tested layered samples showed good conformity with experimental results - i.e. thermal distribution inside and heat release rate that has gone through the sample.

  8. 29 CFR 776.27 - Construction which is related to covered production.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., within the State, of construction materials, such as sand, gravel, brick and other construction materials produced for general local use, is not covered even if the producer also supplies such materials to....19(b)(3); but see § 776.19 (b) (1), (2) and (3); on coverage of furnishing materials “specially...

  9. 29 CFR 776.27 - Construction which is related to covered production.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., within the State, of construction materials, such as sand, gravel, brick and other construction materials produced for general local use, is not covered even if the producer also supplies such materials to....19(b)(3); but see § 776.19 (b) (1), (2) and (3); on coverage of furnishing materials “specially...

  10. 29 CFR 776.27 - Construction which is related to covered production.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., within the State, of construction materials, such as sand, gravel, brick and other construction materials produced for general local use, is not covered even if the producer also supplies such materials to....19(b)(3); but see § 776.19 (b) (1), (2) and (3); on coverage of furnishing materials “specially...

  11. 46 CFR 58.50-15 - Alternate material for construction of independent fuel tanks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Alternate material for construction of independent fuel...) MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS Independent Fuel Tanks § 58.50-15 Alternate material for construction of independent fuel tanks. (a) Materials other than those specifically...

  12. 48 CFR 52.225-11 - Buy American Act-Construction Materials under Trade Agreements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., Dominican Republic, El Salvador, Guatemala, Honduras, Mexico, Morocco, Nicaragua, Oman, Peru, or Singapore..., product, or manufacture of Bahrain, Mexico, or Oman ; or (2) In the case of a construction material that... Bahrain, Mexico, or Oman into a new and different construction material distinct from the materials from...

  13. 48 CFR 52.225-11 - Buy American Act-Construction Materials under Trade Agreements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., Morocco, Nicaragua, Oman, Panama, Peru, or Singapore); (3) A least developed country (Afghanistan, Angola..., product, or manufacture of Bahrain, Mexico, or Oman ; or (2) In the case of a construction material that... Bahrain, Mexico, or Oman into a new and different construction material distinct from the materials from...

  14. Thermoviscoelastic characterization and prediction of Kevlar/epoxy composite laminates

    NASA Technical Reports Server (NTRS)

    Gramoll, K. C.; Dillard, D. A.; Brinson, H. F.

    1990-01-01

    The thermoviscoelastic characterization of Kevlar 49/Fiberite 7714A epoxy composite lamina and the development of a numerical procedure to predict the viscoelastic response of any general laminate constructed from the same material were studied. The four orthotropic material properties, S sub 11, S sub 12, S sub 22, and S sub 66, were characterized by 20 minute static creep tests on unidirectional (0) sub 8, (10) sub 8, and (90) sub 16 lamina specimens. The Time-Temperature Superposition-Principle (TTSP) was used successfully to accelerate the characterization process. A nonlinear constitutive model was developed to describe the stress dependent viscoelastic response for each of the material properties. A numerical procedure to predict long term laminate properties from lamina properties (obtained experimentally) was developed. Numerical instabilities and time constraints associated with viscoelastic numerical techniques were discussed and solved. The numerical procedure was incorporated into a user friendly microcomputer program called Viscoelastic Composite Analysis Program (VCAP), which is available for IBM PC type computers. The program was designed for ease of use. The final phase involved testing actual laminates constructed from the characterized material, Kevlar/epoxy, at various temperatures and load level for 4 to 5 weeks. These results were compared with the VCAP program predictions to verify the testing procedure and to check the numerical procedure used in the program. The actual tests and predictions agreed for all test cases which included 1, 2, 3, and 4 fiber direction laminates.

  15. Special sensors for deformation measurements of different construction materials and structures

    NASA Astrophysics Data System (ADS)

    Glisic, Branko; Inaudi, Daniele; Kronenberg, Pascal; LLoret, Sandra; Vurpillot, Samuel

    1999-05-01

    SOFO is a fiber optic sensor system that allows the monitoring of micrometer deformations over measurement bases up to a few meters. It is particularly adapted to measure civil structures built with conventional civil engineering materials (concrete, steel and timber). It has been successfully tested in different types of structures such as bridges, tunnels and piles. The application of the system is however limited in some case when unusual materials are used in the construction and in other cases by the dimensions of standard SOFO sensors. To extend the domain of application of the current system, special sensors have been developed. In this paper we present four special SOFO sensors: long, membrane, thin and stiff sensors. The long sensor has a measurement basis of several tenths of meters and its purpose is the measurement of deformations in massive and large structures (dames, tunnels). The membrane sensor is for use on laminated materials (e.g. membrane roofing) and it is easy to install by simply gluing it to the structure to be monitored. Since standard sensors can not be used for thin mortar layers because of their cross- section, a thin sensor has been developed, too. Finally, the aim of the stiff sensor is to determine the hardening (solidification) time of concrete. This time is determined by comparing the deformations of a stiff and a standard sensor, closely placed in the concrete at the very early age. The design of these sensors is presented along with significant application examples.

  16. Indigenous lunar construction materials

    NASA Technical Reports Server (NTRS)

    Rogers, Wayne; Sture, Stein

    1991-01-01

    The objectives are the following: to investigate the feasibility of the use of local lunar resources for construction of a lunar base structure; to develop a material processing method and integrate the method with design and construction of a pressurized habitation structure; to estimate specifications of the support equipment necessary for material processing and construction; and to provide parameters for systems models of lunar base constructions, supply, and operations. The topics are presented in viewgraph form and include the following: comparison of various lunar structures; guidelines for material processing methods; cast lunar regolith; examples of cast basalt components; cast regolith process; processing equipment; mechanical properties of cast basalt; material properties and structural design; and future work.

  17. Development of a Highly Stressed Bladed Rotor Made of a CFRP Using the Tailored Fiber Placement Technology

    NASA Astrophysics Data System (ADS)

    Uhlig, K.; Spickenheuer, A.; Bittrich, L.; Heinrich, G.

    2013-05-01

    Increasing the rotational frequency of bladed rotors used in turbomachinery leads to their increased efficiency and performance. Especially for turbomolecular pumps, this would allow either higher compression rates or smaller pump dimensions. The maximal rotational frequency is focused on the structural strength of the construction and the material used. Due to their high density, specific strength, and stiffness in the fiber direction, carbon-fiberreinforced plastics (CFRPs) seem to be ideal for such an application. The highly orthotropic material behavior of CFRPs demands new approaches in terms of their manufacturing and dimensioning. As a new approach, a rotor with 17 blades in a blade-integrated disk construction (BLISK) made of a CFRP, allowing a 35% higher burst speed than a bladed rotor made of a high-strength aluminum alloy, was developed. An appropriate fiber layout has to reflect the rotational symmetry, which demands either a radial or tangential fiber orientation. Therefore, the Tailored Fiber Placement (TFP) technology was used, which allows a high flexibility for the fiber layout. For consolidation, resin infiltration was performed using a modified vacuum-assisted process, and the final geometry was generated employing a milling machine. A radius-dependent layer setup of tangential and radial fibers was chosen to maximize the burst speed by using an adapted finite-element analysis. Additionally, a numerical modal analysis and a numerical failure analysis were performed. Finally, the theoretical results were verified on manufactured rotors by an experimental modal analysis and burst tests, where experimental data showed a good coincidence with numerical results.

  18. Ice as a Construction Material

    NASA Technical Reports Server (NTRS)

    Zuppero, Anthony; Lewis, J.

    1998-01-01

    This presentation shows how water and ice can enable exceptionally simple ways to construct structures in deep space. Practicality is underscored by applying advanced tank methods being developed for Mars missions. Water or ice is now known to be present or abundant on most objects in the solar system, starting with the planet Mercury. Thermal processes alone can be used to melt ice . The cold of space can refreeze water back into ice. The anomalous low vapor pressure of water, about 7 mm Hg, permits bladder containers. Tanks or bladders made with modern polymer fiber and film can exhibit very small (<0.1 %) equivalent tankage and ullage fractions and thus hold thousands of tons of water per ton bladder. Injecting water into a bladder whose shape when inflated is the desired final shape, such as a space vehicle, provides a convenient way to construct large structures. In space, structures of 1O,OOO-T mass become feasible because the bladder mass is low enough to be launched. The bladder can weigh 1OOO times less than its contents, or 10 T. The bladder would be packed like a parachute. Shaped memory materials and/or gas inflation could reestablish the desired structure shape after unpacking. The water comes from space resources. An example examines construction of torus space vehicle with 100-m nominal dimension. People would live inside the torus. A torus, like a tire on an automobile, would spin and provide synthetic gravity at its inner surface. A torus of order 100 m across would provide a gravity with gradients low enough to mitigate against vertigo.

  19. The Cryogenic, High-Accuracy, Refraction Measuring System (CHARMS): A New Facility for Cryogenic Infrared through Vacuum Far-Ultraviolet Refractive Index Measurements

    NASA Technical Reports Server (NTRS)

    Frey, Bradley J.; Leviton, Douglas B.

    2004-01-01

    The optical designs of future NASA infrared (IR) missions and instruments, such as the James Webb Space Telescope's (JWST) Near-Mixed Camera (NIRCam), will rely on accurate knowledge of the index of refraction of various IR optical materials at cryogenic temperatures. To meet this need, we have developed a Cryogenic, High-Accuracy Refraction Measuring System (CHARMS). In this paper we discuss the completion of the design and construction of CHARMS as well as the engineering details that constrained the final design and hardware implementation. In addition, we will present our first light, cryogenic, IR index of refraction data for LiF, BaF2, and CaF2, and compare our results to previously published data for these materials.

  20. Extreme Precision Antenna Reflector Study Results

    NASA Technical Reports Server (NTRS)

    Sharp, G. R.; Gilger, L. D.; Ard, K. E.

    1985-01-01

    Thermal and mechanical distortion degrade the RF performance of antennas. The complexity of future communications antennas requires accurate, dimensionally stable antenna reflectors and structures built from materials other than those currently used. The advantages and disadvantages of using carbon fibers in an epoxy matrix are reviewed as well as current reflector fabrications technology and adjustment. The manufacturing sequence and coefficient of thermal expansion of carbon fiber/borosilicate glass composites is described. The construction of a parabolic reflector from this material and the assembling of both reflector and antenna are described. A 3M-aperture-diameter carbon/glass reflector that can be used as a subassembly for large reflectors is depicted. The deployment sequence for a 10.5M-aperture-diameter antenna, final reflector adjustment, and the deployment sequence for large reflectors are also illustrated.

  1. Sediment accretion and carbon storage in constructed wetlands receiving water treated with metal-based coagulants

    USGS Publications Warehouse

    Stumpner, Elizabeth; Kraus, Tamara; Liang, Yan; Bachand, Sandra M.; Horwath, William R.; Bachand, Philip A.M.

    2018-01-01

    In many regions of the world, subsidence of organic rich soils threatens levee stability and freshwater supply, and continued oxidative loss of organic matter contributes to greenhouse gas production. To counter subsidence in the Sacramento-San Joaquin Delta of northern California, we examined the feasibility of using constructed wetlands receiving drainage water treated with metal-based coagulants to accrete mineral material along with wetland biomass, while also sequestering carbon in wetland sediment. Nine field-scale wetlands were constructed which received local drainage water that was either untreated (control), or treated with polyaluminum chloride (PAC) or iron sulfate (FeSO4) coagulants. After 23 months of flooding and coagulant treatment, sediment samples were collected near the inlet, middle, and outlet of each wetland to determine vertical accretion rates, bulk density, sediment composition, and carbon sequestration rates. Wetlands treated with PAC had the highest and most spatially consistent vertical accretion rates (~6 cm year-1), while the FeSO4 wetlands had similarly high accretion rates near the inlet but rates similar to the untreated wetland (~1.5 cm year-1) at the middle and outlet sites. The composition of the newly accreted sediment in the PAC and FeSO4 treatments was high in the added metal (aluminum and iron, respectively), but the percent metal by weight was similar to native soils of California. As has been observed in other constructed wetlands, the newly accreted sediment material had lower bulk densities than the native soil material (0.04-0.10 g cm-3 versus 0.2-0.3 g cm-3), suggesting these materials will consolidate over time. Finally, this technology accelerated carbon burial, with rates in PAC treated wetland (0.63 kg C m-2 yr-1) over 2-fold greater than the untreated control (0.28 kg C m-2 yr-1). This study demonstrates the feasibility of using constructed wetlands treated with coagulants to reverse subsidence by accreting the resulting organo-metal flocculent and storing carbon at rates exceeding untreated wetlands. Management and design questions remain for how to best integrate this technology into heavily subsided land to lower the risks and consequences associated with levee failure, improve water quality, and ultimately restore these lands to tidal wetlands.

  2. 75 FR 42820 - Notice of Availability of a Final Environmental Assessment (Final EA) and a Finding of No...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-22

    ... include: demolition of approximately 6,435 feet of Airport Road; construction of approximately 6,405 feet of relocated Airport Road; installation of ILS components on the north end of Runway 20; construction of access roads and equipment shelter buildings; construction of the parallel taxiway/ramp expansion...

  3. LEVERAGING AGING MATERIALS DATA TO SUPPORT EXTENSION OF TRANSPORTATION SHIPPING PACKAGES SERVICE LIFE

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dunn, K.; Bellamy, S.; Daugherty, W.

    Nuclear material inventories are increasingly being transferred to interim storage locations where they may reside for extended periods of time. Use of a shipping package to store nuclear materials after the transfer has become more common for a variety of reasons. Shipping packages are robust and have a qualified pedigree for performance in normal operation and accident conditions but are only certified over an approved transportation window. The continued use of shipping packages to contain nuclear material during interim storage will result in reduced overall costs and reduced exposure to workers. However, the shipping package materials of construction must maintainmore » integrity as specified by the safety basis of the storage facility throughout the storage period, which is typically well beyond the certified transportation window. In many ways, the certification processes required for interim storage of nuclear materials in shipping packages is similar to life extension programs required for dry cask storage systems for commercial nuclear fuels. The storage of spent nuclear fuel in dry cask storage systems is federally-regulated, and over 1500 individual dry casks have been in successful service up to 20 years in the US. The uncertainty in final disposition will likely require extended storage of this fuel well beyond initial license periods and perhaps multiple re-licenses may be needed. Thus, both the shipping packages and the dry cask storage systems require materials integrity assessments and assurance of continued satisfactory materials performance over times not considered in the original evaluation processes. Test programs for the shipping packages have been established to obtain aging data on materials of construction to demonstrate continued system integrity. The collective data may be coupled with similar data for the dry cask storage systems and used to support extending the service life of shipping packages in both transportation and storage.« less

  4. Programming chemistry in DNA-addressable bioreactors

    PubMed Central

    Fellermann, Harold; Cardelli, Luca

    2014-01-01

    We present a formal calculus, termed the chemtainer calculus, able to capture the complexity of compartmentalized reaction systems such as populations of possibly nested vesicular compartments. Compartments contain molecular cargo as well as surface markers in the form of DNA single strands. These markers serve as compartment addresses and allow for their targeted transport and fusion, thereby enabling reactions of previously separated chemicals. The overall system organization allows for the set-up of programmable chemistry in microfluidic or other automated environments. We introduce a simple sequential programming language whose instructions are motivated by state-of-the-art microfluidic technology. Our approach integrates electronic control, chemical computing and material production in a unified formal framework that is able to mimic the integrated computational and constructive capabilities of the subcellular matrix. We provide a non-deterministic semantics of our programming language that enables us to analytically derive the computational and constructive power of our machinery. This semantics is used to derive the sets of all constructable chemicals and supermolecular structures that emerge from different underlying instruction sets. Because our proofs are constructive, they can be used to automatically infer control programs for the construction of target structures from a limited set of resource molecules. Finally, we present an example of our framework from the area of oligosaccharide synthesis. PMID:25121647

  5. 19 CFR 123.18 - Equipment and materials for constructing bridges or tunnels between the United States and Canada...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 1 2011-04-01 2011-04-01 false Equipment and materials for constructing bridges... WITH CANADA AND MEXICO International Traffic § 123.18 Equipment and materials for constructing bridges.... Equipment for use in construction of bridges or tunnels between the United States and Canada or Mexico shall...

  6. Bioinks for 3D bioprinting: an overview.

    PubMed

    Gungor-Ozkerim, P Selcan; Inci, Ilyas; Zhang, Yu Shrike; Khademhosseini, Ali; Dokmeci, Mehmet Remzi

    2018-05-01

    Bioprinting is an emerging technology with various applications in making functional tissue constructs to replace injured or diseased tissues. It is a relatively new approach that provides high reproducibility and precise control over the fabricated constructs in an automated manner, potentially enabling high-throughput production. During the bioprinting process, a solution of a biomaterial or a mixture of several biomaterials in the hydrogel form, usually encapsulating the desired cell types, termed the bioink, is used for creating tissue constructs. This bioink can be cross-linked or stabilized during or immediately after bioprinting to generate the final shape, structure, and architecture of the designed construct. Bioinks may be made from natural or synthetic biomaterials alone, or a combination of the two as hybrid materials. In certain cases, cell aggregates without any additional biomaterials can also be adopted for use as a bioink for bioprinting processes. An ideal bioink should possess proper mechanical, rheological, and biological properties of the target tissues, which are essential to ensure correct functionality of the bioprinted tissues and organs. In this review, we provide an in-depth discussion of the different bioinks currently employed for bioprinting, and outline some future perspectives in their further development.

  7. Structural Solutions for Low-Cost Bamboo Frames: Experimental Tests and Constructive Assessments

    PubMed Central

    Sassu, Mauro; De Falco, Anna; Giresini, Linda; Puppio, Mario Lucio

    2016-01-01

    Experimental tests and constructive assessments are presented for a simple bamboo framed structure with innovative low-cost and low technology joints, specifically conceived for small buildings in developing countries. Two full scale one-storey bamboo frames have been designed by using the simplest joints solution among three different tested typologies. The entire building process is based on low-technology and natural materials: bamboo canes, wooden cylinders, plywood plates and canapé rods. The first full scale specimen (Unit A) is a one-storey single deck truss structure subjected to monotonic collapse test; the second full scale specimen (Unit B) is a one-storey double deck truss structure used to evaluate the construction time throughout assembling tests. The first full scale specimen showed ductility in collapse and ease in strengthening; the second one showed remarkable ease and speed in assembling structural elements. Finally several constructive solutions are suggested for the design of simple one-storey buildings; they are addressed to four purposes (housing, school, chapel, health center) by the composition of the proposed full scale bamboo frames. Ease of use and maintenance with a low level of technology contribute to application in developing countries although not exclusively. PMID:28773472

  8. Impact of moisture content in AAC on its heat insulation properties

    NASA Astrophysics Data System (ADS)

    Rubene, S.; Vilnitis, M.

    2017-10-01

    One of the most popular trends in construction industry is sustainable construction. Therefore, application of construction materials with high insulation characteristics has significantly increased during the past decade. Requirements for application of construction materials with high insulation parameters are required not only by means of energy saving and idea of sustainable construction but also by legislative requirements. Autoclaved aerated concrete (AAC) is a load bearing construction material, which has high heat insulation parameters. However, if the AAC masonry construction has high moisture content the heat insulation properties of the material decrease significantly. This fact lead to the necessity for the on-site control of moisture content in AAC in order to avoid inconsistency between the designed and actual thermal resistivity values of external delimiting constructions. Research of the impact of moisture content in AAC on its heat insulation properties has been presented in this paper.

  9. 38. From Final Construction Report on the Haleakala Road ProjectNR7, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    38. From Final Construction Report on the Haleakala Road Project--NR-7, Hawaii National Park, Island of Maui, Territory of Hawaii. BRIDGE AT STATION 85+. - Haleakala National Park Roads, Pukalani, Maui County, HI

  10. RECOMMENDED FOUNDATION FILL MATERIALS CONSTRUCTION STANDARD OF THE FLORIDA RADON RESEARCH PROGRAM

    EPA Science Inventory

    The report summarizes the technical basis for a recommended foundation fill materials standard for new construction houses in Florida. he radon-control construction standard was developed by the Florida Radon Research Program (FRRP). ill material standards are formulated for: (1)...

  11. Activity measurements of a suite of radionuclides (241Am, 239,240Pu, 238Pu, 238U, 234U, 235U, 232Th, 230Th, 228Th, 228Ra, 137Cs, 210Pb, 90Sr and 40K) in biota reference material (Ocean Shellfish): CCRI(II)-S3

    NASA Astrophysics Data System (ADS)

    Nour, S.; Karam, L. R.; Inn, K. G. W.

    2012-01-01

    In 2005, the CCRI decided that a comparison undertaken from 2002 to 2008 by the NIST (under the auspices of the Inter-America Metrology System [SIM]) in the development of a new biota (Ocean Shellfish) standard reference material (SRM) was sufficiently well constructed that it could be converted into a supplementary comparison under CCRI(II), with comparison identifier CCRI(II)-S3. This would enable the comparison to be used to support calibration and measurement capability (CMC) claims for radionuclide measurements in reference materials (specifically, animal-based organic materials). Previous comparisons of radionuclides have been of single or multiple nuclides in non-complex matrices and results of such could not be extended to support capabilities to measure the same nuclides in reference materials. The results of this comparison have been used to determine the certified reference value of the SRM. The key comparison working group (KCWG) of the CCRI(II) has approved this approach as a mechanism to link all the results to certified 'reference values' in lieu of the key comparison reference value (KCRV) of these specified radionuclides in this type of matrix (shellfish) so as to support CMCs of similar materials submitted by the present participants. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  12. Experimental Study of the Conditions for Quenching Forest Combustible Materials

    NASA Astrophysics Data System (ADS)

    Antonov, D. V.; Volkov, R. S.; Zhdanova, A. O.; Kuznetsov, G. V.; Strizhak, P. A.

    2017-05-01

    To confirm the possibility of quenching forest combustible materials by small volumes of water, experimental studies have been made of the processes of interaction of droplets, films, and aerosol flows of water with small sources of combustion of typical forest combustible materials — birch leaves, pine needles, birch and asp twigs. Model combustion sources in the form of cylinders of diameter 20-60 mm and height 40-100 mm were constructed. With the use of high-speed video recording, the characteristic times of thermal decomposition of forest combustibles and the times of suppressing combustion of these materials under various conditions of their interaction with water (pulsed supply of aerosol, injection of water ″mist″ with droplets of radius up to 100 μm, sequential supply of large drops of radius about 1.5 mm) have been determined. Volumes of water sufficient for suppressing combustion depending on the method of supplying it onto the surface of the reacting forest combustible have been determined. Estimates have been made of the nonreacted portion of the material by comparing the initial mass of the sample of the forest combustible with its final mass (upon quenching the material).

  13. Analysis of Surface Charging for a Candidate Solar Sail Mission Using NASCAP-2K

    NASA Technical Reports Server (NTRS)

    Parker, Linda Neergaard; Minow, Joseph L.; Davis, V. A.; Mandell, Myron; Gardner, Barbara

    2005-01-01

    The characterization of the electromagnetic interaction for a solar sail in the solar wind environment and identification of viable charging mitigation strategies are critical solar sail mission design tasks. Spacecraft charging has important implications both for science applications and for lifetime and reliability issues of sail propulsion systems. To that end, surface charging calculations of a candidate 150-meter-class solar sail spacecraft for the 0.5 AU solar polar and 1.9 AU LI solar wind environments are performed. A model of the spacecraft with candidate materials having appropriate electrical properties is constructed using Object Toolkit. The spacecraft charging analysis is performed using Nascap-2k. the NASA/AFRL sponsored spacecraft charging analysis tool. Nominal and atypical solar wind environments appropriate for the 0.5 AU and 1.0 AU missions are used to establish current collection of solar wind ions and electrons. Finally, a geostationary orbit environment case is included to demonstrate a bounding example of extreme (negative) charging of a solar sail spacecraft. Results from the charging analyses demonstrate that minimal differential potentials (and resulting threat of electrostatic discharge) occur when the spacecraft is constructed entirely of conducting materials, as anticipated from standard guidelines for mitigation of spacecraft charging issues. Examples with dielectric materials exposed to the space environment exhibit differential potentials ranging from a few volts to extreme potentials in the kilovolt range.

  14. Analysis of Surface Charging for a Candidate Solar Sail Mission Using Nascap-2k

    NASA Technical Reports Server (NTRS)

    Parker, Linda Neergaard; Minow, Joseph I.; Davis, Victoria; Mandell, Myron; Gardner, Barbara

    2005-01-01

    The characterization of the electromagnetic interaction for a solar sail in the solar wind environment and identification of viable charging mitigation strategies are critical solar sail mission design task. Spacecraft charging has important implications both for science applications and for lifetime and reliability issues of sail propulsion systems. To that end, surface charging calculations of a candidate 150-meter-class solar sail spacecraft for the 0.5 AU solar polar and 1.0 AU L1 solar wind environments are performed. A model of the spacecraft with candidate materials having appropriate electrical properties is constructed using Object Toolkit. The spacecraft charging analysis is performed using Nascap-2k, the NASA/AFRL sponsored spacecraft charging analysis tool. Nominal and atypical solar wind environments appropriate for the 0.5 AU and 1.0 AU missions are used to establish current collection of solar wind ions and electrons. Finally, a geostationary orbit environment case is included to demonstrate a bounding example of extreme (negative) charging of a solar sail spacecraft. Results from the charging analyses demonstrate that minimal differential potentials (and resulting threat of electrostatic discharge) occur when the spacecraft is constructed entirely of conducting materials, as anticipated from standard guidelines for mitigation of spacecraft charging issues. Examples with dielectric materials exposed to the space environment exhibit differential potentials ranging from a few volts to extreme potentials in the kilovolt range.

  15. Factors affecting the mechanical behavior of collagen hydrogels for skin tissue engineering.

    PubMed

    Pensalfini, Marco; Ehret, Alexander E; Stüdeli, Silvia; Marino, Daniela; Kaech, Andres; Reichmann, Ernst; Mazza, Edoardo

    2017-05-01

    The effect of the production factors yielding a functional dermal substitute was investigated by means of monotonic and cyclic uniaxial tensile tests, as well as electron microscopy visualizations. The role of (i) plastic compression, (ii) product incubation, and (iii) cell permanence in the collagenous matrix in order to achieve a skin-like behavior were characterized in terms of material and structural stiffness, in-plane kinematics, and cyclic response, as well as pore size and network density. The plastic compression resulted in a denser and stiffer material, while no corresponding change was observed in the behavior of the entire structure. This was related to the progressive reduction in product thickness and amount of excess water, rather than to formation of new crosslinks between fibers. Contrary, irrespective of the presence of human fibroblasts, the product incubation induced both material and structural stiffening, indicating the formation of a denser network. These results were confirmed by similar evolutions in the construct in-plane kinematics and cyclic stress reduction. Finally, comparison of constructs incubated in different culture media indicated a determinant contribution of the biochemical environment, rather than of the seeded cells, to the achieved mechanical properties. The observed features are relevant in terms of mechanical biocompatibility of the implant and might direct future optimizations of the production process in order to rapidly attain the desired mechanical properties. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Personalized development of human organs using 3D printing technology.

    PubMed

    Radenkovic, Dina; Solouk, Atefeh; Seifalian, Alexander

    2016-02-01

    3D printing is a technique of fabricating physical models from a 3D volumetric digital image. The image is sliced and printed using a specific material into thin layers, and successive layering of the material produces a 3D model. It has already been used for printing surgical models for preoperative planning and in constructing personalized prostheses for patients. The ultimate goal is to achieve the development of functional human organs and tissues, to overcome limitations of organ transplantation created by the lack of organ donors and life-long immunosuppression. We hypothesized a precision medicine approach to human organ fabrication using 3D printed technology, in which the digital volumetric data would be collected by imaging of a patient, i.e. CT or MRI images followed by mathematical modeling to create a digital 3D image. Then a suitable biocompatible material, with an optimal resolution for cells seeding and maintenance of cell viability during the printing process, would be printed with a compatible printer type and finally implanted into the patient. Life-saving operations with 3D printed implants were already performed in patients. However, several issues need to be addressed before translational application of 3D printing into clinical medicine. These are vascularization, innervation, and financial cost of 3D printing and safety of biomaterials used for the construct. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Continued Water-Based Phase Change Material Heat Exchanger Development

    NASA Technical Reports Server (NTRS)

    Hansen, Scott W.; Sheth, Rubik B.; Poynot, Joe; Giglio, Tony; Ungar, Gene K.

    2015-01-01

    In a cyclical heat load environment such as low Lunar orbit, a spacecraft's radiators are not sized to meet the full heat rejection demands. Traditionally, a supplemental heat rejection device (SHReD) such as an evaporator or sublimator is used to act as a "topper" to meet the additional heat rejection demands. Utilizing a Phase Change Material (PCM) heat exchanger (HX) as a SHReD provides an attractive alternative to evaporators and sublimators as PCM HX's do not use a consumable, thereby leading to reduced launch mass and volume requirements. In continued pursuit of water PCM HX development two full-scale, Orion sized water-based PCM HX's were constructed by Mezzo Technologies. These HX's were designed by applying prior research on freeze front propagation to a full-scale design. Design options considered included bladder restraint and clamping mechanisms, bladder manufacturing, tube patterns, fill/drain methods, manifold dimensions, weight optimization, and midplate designs. Two units, Units A and B, were constructed and differed only in their midplate design. Both units failed multiple times during testing. This report highlights learning outcomes from these tests and are applied to a final sub-scale PCM HX which is slated to be tested on the ISS in early 2017.

  18. 46 CFR 160.058-3 - Materials, workmanship, construction and performance requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 6 2013-10-01 2013-10-01 false Materials, workmanship, construction and performance requirements. 160.058-3 Section 160.058-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Desalter Kits, Sea...

  19. 46 CFR 160.058-3 - Materials, workmanship, construction and performance requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 6 2014-10-01 2014-10-01 false Materials, workmanship, construction and performance requirements. 160.058-3 Section 160.058-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Desalter Kits, Sea...

  20. 46 CFR 160.058-3 - Materials, workmanship, construction and performance requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 6 2011-10-01 2011-10-01 false Materials, workmanship, construction and performance requirements. 160.058-3 Section 160.058-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Desalter Kits, Sea...

  1. 46 CFR 160.058-3 - Materials, workmanship, construction and performance requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 6 2012-10-01 2012-10-01 false Materials, workmanship, construction and performance requirements. 160.058-3 Section 160.058-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Desalter Kits, Sea...

  2. 46 CFR 160.058-3 - Materials, workmanship, construction and performance requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 6 2010-10-01 2010-10-01 false Materials, workmanship, construction and performance requirements. 160.058-3 Section 160.058-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Desalter Kits, Sea...

  3. An analysis of innovation in materials and energy

    NASA Astrophysics Data System (ADS)

    Connelly, Michael

    This dissertation presents an analysis of innovation in engineering materials and energy sources. More than fifty engineering materials and fourteen energy sources were selected for an evaluation of the relationship between the yearly production activity and yearly patent counts, which may be considered as a measure of innovation, for each. Through the employment of correlation theory, best-fit and origin shift analyses, it has been determined here that engineering materials and energy sources display similar life cycle and innovative activity behaviors. Correlation theory revealed a relationship between the yearly production and yearly patent counts indicating the extent that production and innovation affect each other. Best-fit analysis determined that four-stage life cycles exist for both engineering materials (metals and non-metals) and energy sources. Correlation and best-fit indicators of an estimated Stage III are confirmed by the presence of an origin shift of the patent data when compared to the production data which indicates that patents, or innovation, are driving, or being driven by, production. This driving force could represent the constructive or destructive side of the innovative process, with such sides being delineated by a possible universal constant above which there is destructive innovative behavior and below which exists constructive innovation. The driving force may also illustrate the manner in which an engineering material or energy source transitions into an innovatively less active state, enter Stage IV and possibly become a commodity. A possible Stage V, indicating "Final Death", is introduced in which production is on a steep decline with no signs of recovery. Additionally, innovatively active energy sources are often found to utilize or be supported by innovatively active engineering materials. A model is presented that can be used for the evaluation of innovation and production that can be applied to both engineering materials and energy sources that may be used to predict the innovative behavior of these resources in order that they can be more effectively allocated and utilized.

  4. Wind energy converter with high-speed vertical axis rotor and straight rotor blades

    NASA Astrophysics Data System (ADS)

    Zelck, G.

    1982-11-01

    Complete documents for a wind energy converter with a vertical axis rotor and straight blades (H-rotor) were developed. The 2 blade rotor with rigid and rectangular air foils in wooden construction reaches the nominal output of 75 KVA from 11,4 m/sec. wind velocity onwards. The development activities are supported by wind tunnel and component tests. The final design selected was based upon previous development work. Trade offs show that the design is more advantageous compared to other designs. The use of wood as a material for the rotary and horizontal blade supports gives positive result.

  5. Particle beam generator using a radioactive source

    DOEpatents

    Underwood, D.G.

    1993-03-30

    The apparatus of the present invention selects from particles emitted by a radioactive source those particles having momentum within a desired range and focuses the selected particles in a beam having at least one narrow cross-dimension, and at the same time attenuates potentially disruptive gamma rays and low energy particles. Two major components of the present invention are an achromatic bending and focusing system, which includes sector magnets and quadrupole, and a quadrupole doublet final focus system. Permanent magnets utilized in the apparatus are constructed of a ceramic (ferrite) material which is inexpensive and easily machined.

  6. Stepwise Bay Annulation of Indigo for the Synthesis of Desymmetrized Electron Acceptors and Donor–Acceptor Constructs

    DOE PAGES

    Kolaczkowski, Matthew A.; He, Bo; Liu, Yi

    2016-10-10

    In this work, a selective stepwise annulation of indigo has been demonstrated as a means of providing both monoannulated and differentially double-annulated indigo derivatives. Disparate substitution of the electron accepting bay-annulated indigo system allows for fine control over both the electronic properties as well as donor-acceptor structural architectures. Optical and electronic properties were characterized computationally as well as through UV-vis absorption spectroscopy and cyclic voltammetry. Finally, this straightforward method provides a modular approach for the design of indigo-based materials with tailored optoelectronic properties.

  7. The Airfloat HL project. [design analysis of airships and lift devices for materials handling

    NASA Technical Reports Server (NTRS)

    Mowforth, E.

    1975-01-01

    A design study is described for a large low-cost rigid airship intended primarily for the movement of large indivisible loads (cargo) between industrial sites. A survey of the ship and its overall performance is followed by accounts of the operational procedures for the above function and for an alternative application to unit module transfer between fixed terminals. A final section indicates the estimated costs of construction and operation. Safety factors are also considered. Lifting devices such as winches, hoists are shown and described, and airship configurations are also shown.

  8. Particle beam generator using a radioactive source

    DOEpatents

    Underwood, David G.

    1993-01-01

    The apparatus of the present invention selects from particles emitted by a radioactive source those particles having momentum within a desired range and focuses the selected particles in a beam having at least one narrow cross-dimension, and at the same time attenuates potentially disruptive gamma rays and low energy particles. Two major components of the present invention are an achromatic bending and focusing system, which includes sector magnets and quadrupole, and a quadrupole doublet final focus system. Permanent magnets utilized in the apparatus are constructed of a ceramic (ferrite) material which is inexpensive and easily machined.

  9. Solar powered multipurpose remotely powered aircraft

    NASA Technical Reports Server (NTRS)

    Alexandrou, A. N.; Durgin, W. W.; Cohn, R. F.; Olinger, D. J.; Cody, Charlotte K.; Chan, Agnes; Cheung, Kwok-Hung; Conley, Kristin; Crivelli, Paul M.; Javorski, Christian T.

    1992-01-01

    Increase in energy demands coupled with rapid depletion of natural energy resources have deemed solar energy as an attractive alternative source of power. The focus was to design and construct a solar powered, remotely piloted vehicle to demonstrate the feasibility of solar energy as an effective, alternate source of power. The final design included minimizing the power requirements and maximizing the strength-to-weight and lift-to-drag ratios. Given the design constraints, Surya (the code-name given to the aircraft), is a lightweight aircraft primarily built using composite materials and capable of achieving level flight powered entirely by solar energy.

  10. Broadband metasurfaces enabling arbitrarily large delay-bandwidth products

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ginis, Vincent; Tassin, Philippe; Koschny, Thomas

    2016-01-19

    Metasurfaces allow for advanced manipulation of optical signals by imposing phase discontinuities across flat interfaces. Unfortunately, these phase shifts remain restricted to values between 0 and 2π, limiting the delay-bandwidth product of such sheets. Here, we develop an analytical tool to design metasurfaces that mimic three-dimensional materials of arbitrary thickness. In this way, we demonstrate how large phase discontinuities can be realized by combining several subwavelength Lorentzian resonances in the unit cell of the surface. Finally, our methods open up the temporal response of metasurfaces and may lead to the construction of metasurfaces with a plethora of new optical functions.

  11. Feasibility study of applying an advanced composite structure technique to the fabrication of helicopter rotor blades

    NASA Technical Reports Server (NTRS)

    Gleich, D.

    1972-01-01

    The fabrication of helicopter rotary wings from composite materials is discussed. Two composite spar specimens consisting of compressively prestressed stainless steel liner over-wrapped with pretensioned fiberglass were constructed. High liner strength and toughness together with the prescribed prestresses and final sizing of the part are achieved by means of cryogenic stretch forming of the fiber wrapped composite spar at minus 320 F, followed by release of the forming pressure and warm up to room temperature. The prestresses are chosen to provide residual compression in the metal liner under operating loads.

  12. Field trial of solvent-free emulsion in Oregon : final report.

    DOT National Transportation Integrated Search

    2003-03-01

    This final report summarizes construction, laboratory and performance information gathered by ODOT personnel from a single field trial of solvent-free emulsion mix constructed in June 2001. The solvent-free emulsion mix presented several placement pr...

  13. The application of waste fly ash and construction-waste in cement filling material in goaf

    NASA Astrophysics Data System (ADS)

    Chen, W. X.; Xiao, F. K.; Guan, X. H.; Cheng, Y.; Shi, X. P.; Liu, S. M.; Wang, W. W.

    2018-01-01

    As the process of urbanization accelerated, resulting in a large number of abandoned fly ash and construction waste, which have occupied the farmland and polluted the environment. In this paper, a large number of construction waste and abandoned fly ash are mixed into the filling material in goaf, the best formula of the filling material which containing a large amount of abandoned fly ash and construction waste is obtained, and the performance of the filling material is analyzed. The experimental results show that the cost of filling material is very low while the performance is very good, which have a good prospect in goaf.

  14. 46 CFR 160.031-3 - Materials, construction, workmanship, and performance requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Appliance, Shoulder Gun Type (and Equipment) § 160.031-3 Materials, construction, workmanship, and performance requirements. (a) All materials used in the construction of shoulder gun type line-throwing... affecting appearance or serviceability of the gun. (d) The gun, when loaded and fired in accordance with the...

  15. 46 CFR 160.031-3 - Materials, construction, workmanship, and performance requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Appliance, Shoulder Gun Type (and Equipment) § 160.031-3 Materials, construction, workmanship, and performance requirements. (a) All materials used in the construction of shoulder gun type line-throwing... affecting appearance or serviceability of the gun. (d) The gun, when loaded and fired in accordance with the...

  16. 46 CFR 160.031-3 - Materials, construction, workmanship, and performance requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Appliance, Shoulder Gun Type (and Equipment) § 160.031-3 Materials, construction, workmanship, and performance requirements. (a) All materials used in the construction of shoulder gun type line-throwing... affecting appearance or serviceability of the gun. (d) The gun, when loaded and fired in accordance with the...

  17. 46 CFR 160.031-3 - Materials, construction, workmanship, and performance requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Appliance, Shoulder Gun Type (and Equipment) § 160.031-3 Materials, construction, workmanship, and performance requirements. (a) All materials used in the construction of shoulder gun type line-throwing... affecting appearance or serviceability of the gun. (d) The gun, when loaded and fired in accordance with the...

  18. 46 CFR 160.031-3 - Materials, construction, workmanship, and performance requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Appliance, Shoulder Gun Type (and Equipment) § 160.031-3 Materials, construction, workmanship, and performance requirements. (a) All materials used in the construction of shoulder gun type line-throwing... affecting appearance or serviceability of the gun. (d) The gun, when loaded and fired in accordance with the...

  19. Information systems for material flow management in construction processes

    NASA Astrophysics Data System (ADS)

    Mesároš, P.; Mandičák, T.

    2015-01-01

    The article describes the options for the management of material flows in the construction process. Management and resource planning is one of the key factors influencing the effectiveness of construction project. It is very difficult to set these flows correctly. The current period offers several options and tools to do this. Information systems and their modules can be used just for the management of materials in the construction process.

  20. Kernels, Degrees of Freedom, and Power Properties of Quadratic Distance Goodness-of-Fit Tests

    PubMed Central

    Lindsay, Bruce G.; Markatou, Marianthi; Ray, Surajit

    2014-01-01

    In this article, we study the power properties of quadratic-distance-based goodness-of-fit tests. First, we introduce the concept of a root kernel and discuss the considerations that enter the selection of this kernel. We derive an easy to use normal approximation to the power of quadratic distance goodness-of-fit tests and base the construction of a noncentrality index, an analogue of the traditional noncentrality parameter, on it. This leads to a method akin to the Neyman-Pearson lemma for constructing optimal kernels for specific alternatives. We then introduce a midpower analysis as a device for choosing optimal degrees of freedom for a family of alternatives of interest. Finally, we introduce a new diffusion kernel, called the Pearson-normal kernel, and study the extent to which the normal approximation to the power of tests based on this kernel is valid. Supplementary materials for this article are available online. PMID:24764609

  1. 35. From Final Construction Report on the Haleakala Road ProjectNR7, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    35. From Final Construction Report on the Haleakala Road Project--NR-7, Hawaii National Park, Island of Maui, Territory of Hawaii. LOOKING BACK FROM STATION 335 AT RETURN CURVE. - Haleakala National Park Roads, Pukalani, Maui County, HI

  2. 36. From Final Construction Report on the Haleakala Road ProjectNR7, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    36. From Final Construction Report on the Haleakala Road Project--NR-7, Hawaii National Park, Island of Maui, Territory of Hawaii. TYPICAL RUBBLE MASONRY HEADWALL AND BOX CULVERT. - Haleakala National Park Roads, Pukalani, Maui County, HI

  3. [Sensory stimulation: new apparatus for demented men].

    PubMed

    de Groot, M D; Molenbroek, J F

    2001-10-01

    In order to study the feasibility of new sensorily stimulating material for elderly demented men, their behaviour was observed while the material was handed over to them. The newly developed materials consisted of five different constructions, i.e. a mirrorbox, a simple hand-operated stroboscope, a spring-operated ball for ringing a bell, two rotating wooden cogwheels, and a box having a sandpaper bottom of different grains causing a tactile contrast. In their verbal and nonverbal responses the demented men showed clear signs of interest in the constructions and the materials. The seven participating men showed much interest in materials made of wood and metal, and in the working of the constructions. The different constructions and materials could be combined into one complete 'snoezelproduct'.

  4. Challenging social myths and stereotypes of women and aging: heterosexual women talk about sex.

    PubMed

    Hinchliff, Sharron; Gott, Merryn

    2008-01-01

    Cultural representations of aging and sexuality combine to paint a particular picture of mid and later life for women: menopause is constructed as a time when women either lose or renew their interest in sex, and later life a time when sexual activity no longer assumes importance yet remains vital to healthy aging. This article examines the importance of sexual activity to "older" women, paying particular attention to how they negotiate such representations. In-depth interviews were conducted with 19 women aged 50 and older recruited from Sheffield, UK. A material-discursive analysis revealed that whilst participants rejected the asexual discourse of aging they accepted it for women older than themselves. They constructed women per se as sexually complex, in comparison to men, making sexual activity "risky business" for women, and positioned their own sexual desire as responsive, either to a man's sexual desire or to their own hormones. Finally, sexual activity was constructed as having psychological and physiological benefits for couples within committed relationships. The findings are discussed in terms of their implications for research, theory and clinical practice.

  5. Use of Interim Scaffolding and Neotissue Development to Produce a Scaffold-Free Living Hyaline Cartilage Graft.

    PubMed

    Lau, Ting Ting; Leong, Wenyan; Peck, Yvonne; Su, Kai; Wang, Dong-An

    2015-01-01

    The fabrication of three-dimensional (3D) constructs relies heavily on the use of biomaterial-based scaffolds. These are required as mechanical supports as well as to translate two-dimensional cultures to 3D cultures for clinical applications. Regardless of the choice of scaffold, timely degradation of scaffolds is difficult to achieve and undegraded scaffold material can lead to interference in further tissue development or morphogenesis. In cartilage tissue engineering, hydrogel is the highly preferred scaffold material as it shares many similar characteristics with native cartilaginous matrix. Hence, we employed gelatin microspheres as porogens to create a microcavitary alginate hydrogel as an interim scaffold to facilitate initial chondrocyte 3D culture and to establish a final scaffold-free living hyaline cartilaginous graft (LhCG) for cartilage tissue engineering.

  6. 46 CFR 160.170-23 - Procedure for approval of design, material, or construction change.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 6 2014-10-01 2014-10-01 false Procedure for approval of design, material, or construction change. 160.170-23 Section 160.170-23 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Davit-Launched Liferaft Automatic Release Hooks ...

  7. 46 CFR 160.170-23 - Procedure for approval of design, material, or construction change.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 6 2013-10-01 2013-10-01 false Procedure for approval of design, material, or construction change. 160.170-23 Section 160.170-23 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Davit-Launched Liferaft Automatic Release Hooks ...

  8. 76 FR 14443 - High-Speed Intercity Passenger Rail (HSIPR) Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-16

    ... Environmental Policy Act (NEPA) documentation, final design (FD), and construction. For the purpose of this... designing, engineering, location surveying, mapping, environmental studies, and acquiring rights-of-way..., final design, and construction activities are eligible to receive funding. For applications for Service...

  9. Construction Methods and Materials. School Buildings Planning, Design, and Construction Series No. 5.

    ERIC Educational Resources Information Center

    Odell, John H.

    A school construction guide offers key personnel in school development projects information on the complex task of master planning and construction of schools in Australia. This chapter of the guide provides advice on the various types of construction that may be used, the materials available, and some elementary aspects of the services required…

  10. Development of highly porous scaffolds based on bioactive silicates for dental tissue engineering

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Goudouri, O.M., E-mail: menti.goudouri@ww.uni-erlangen.de; Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki; Theodosoglou, E.

    Graphical abstract: - Highlights: • Synthesis of an Mg-based glass-ceramic via the sol–gel technique. • The heat treatment of the glass-ceramic promoted the crystallization of akermanite. • Akermanite scaffolds coated with gelatin were successfully fabricated. • An HCAp layer was developed on the surface of all scaffolds after 9 days in SBF. - Abstract: Various scaffolding materials, ceramics and especially Mg-based ceramic materials, including akermanite (Ca{sub 2}MgSi{sub 2}O{sub 7}) and diopside (CaMgSi{sub 2}O{sub 6}), have attracted interest for dental tissue regeneration because of their improved mechanical properties and controllable biodegradation. The aim of the present work was the synthesis ofmore » an Mg-based glass-ceramic, which would be used for the construction of workable akermanite scaffolds. The characterization of the synthesized material was performed by Fourier Transform Infrared Spectroscopy (FTIR) X-Ray Diffractometry (XRD) and Scanning Electron Microscopy (SEM). Finally, the apatite forming ability of the scaffolds was assessed by immersion in simulated body fluid. The scaffolds were fabricated by the foam replica technique and were subsequently coated with gelatin to provide a functional surface for increased cell attachment. Finally, SEM microphotographs and FTIR spectra of the scaffolds after immersion in SBF solution indicated the inorganic bioactive character of the scaffolds suitable for the intended applications in dental tissue engineering.« less

  11. Energy content of municipal solid waste bales.

    PubMed

    Ozbay, Ismail; Durmusoglu, Ertan

    2013-07-01

    Baling technology is a preferred method for temporary storage of municipal solid waste (MSW) prior to final disposal. If incineration is intended for final disposal of the bales, the energy content of the baled MSW gains importance. In this study, nine cylindrical bales containing a mix of different waste materials were constructed and several parameters, including total carbon (TC), total organic carbon (TOC), total Kjeldahl nitrogen, moisture content, loss on ignition, gross calorific value and net calorific value (NCV) were determined before the baling and at the end of 10 months of storage. In addition, the relationships between the waste materials and the energy contents of the bales were investigated by the bivariate correlation analyses. At the end, linear regression models were developed in order to forecast the decrease of energy content during storage. While the NCVs of the waste materials before the baling ranged between 6.2 and 23.7 MJ kg(-1) dry basis, they ranged from 1.0 to 16.4 MJ kg(-1) dry basis at the end of the storage period. Moreover, food wastes exhibited the highest negative correlation with NCVs, whereas plastics have significant positive correlation with both NCVs and TCs. Similarly, TOCs and carbon/nitrogen ratios decreased with the increase in food amounts inside the bales. In addition, textile, wood and yard wastes increase the energy content of the bales slightly over the storage period.

  12. Final Report Auto/Steel Partnership Phase II

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cady, C.M.; Chen, S.R.; Gray, G.T. III

    1999-06-09

    This is the final report in which effects of strain-rate, temperature, and stress-state on the yield stress and the strain hardening behavior of many common steels used in automobile construction were investigated. The yield and flow stresses were found to exhibit very high rate sensitivities for most of the steels while the hardening rates were found to be insensitive to strain rate and temperature at lower temperatures or at higher strain rates. This behavior is consistent with the observation that overcoming the intrinsic Peierls stress is shown to be the rate-controlling mechanism in these materials at low temperatures. The dependencemore » of the yield stress on temperature and strain rate was found to decrease while the strain hardening rate increased. The Mechanical Threshold Stress (MTS) model was adopted to model the stress-strain behavior of the steels. Parameters for the constitutive relations were derived for the MTS model and also for the Johnson-Cook (JC) and the Zerilli-Armstrong (ZA) models. The results of this study substantiate the applicability of these models for describing the high strain-rate deformation of these materials. The JC and ZA models, however, due to their use of a power strain hardening law were found to yield constitutive relations for the materials which are strongly dependent on the range of strains for which the models were optimized.« less

  13. New imaging systems in nuclear medicine. Final report, January 1, 1993--December 31, 1995

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    1995-12-31

    The aim of this program has been to improve the performance of positron emission tomography (PET) to achieve high resolution with high sensitivity. Towards this aim, the authors have carried out the following studies: (1) explored new techniques for detection of annihilation radiation including new detector materials and system geometries, specific areas that they have studied include--exploration of factors related to resolution and sensitivity of PET instrumentation including geometry, detection materials and coding, and the exploration of technique to improve the image quality by use of depth of interaction and increased sampling; (2) complete much of the final testing ofmore » PCR-II, an analog-coded cylindrical positron tomograph, developed and constructed during the current funding period; (3) developed the design of a positron microtomograph with mm resolution for quantitative studies in small animals, a single slice version of this device has been designed and studied by use of computer simulation; (4) continued and expanded the program of biological studies in animal models. Current studies have included imaging of animal models of Parkinson`s and Huntington`s disease and cancer. These studies have included new radiopharmaceuticals and techniques involving molecular biology.« less

  14. Tuned apatitic materials: Synthesis, characterization and potential antimicrobial applications

    NASA Astrophysics Data System (ADS)

    Fierascu, Irina; Fierascu, Radu Claudiu; Somoghi, Raluca; Ion, Rodica Mariana; Moanta, Adriana; Avramescu, Sorin Marius; Damian, Celina Maria; Ditu, Lia Mara

    2018-04-01

    Inorganic antimicrobial materials can be viable for multiple applications (related to its use for new buildings with special requirements related to microbiological loading, such as hospital buildings and for consolidation of cultural heritage constructions); also the use of substituted hydroxyapatites for protection of stone artefacts against environmental factors (acidic rain) and biodeterioration it's an option to no longer use of toxic substances. This paper presents methods of synthesis and characterization of the material from the point of view of the obtained structures and final applications. The materials were characterized in terms of composition and morphology (using X-ray Diffraction, X-ray Fluorescence, Inductively coupled plasma-atomic emission spectrometry, Fourier Transform Infrared Spectroscopy, X-ray Photoelectron Spectroscopy, Surface area and pore size determination). Antimicrobial activity was tested against filamentous fungi strains and pathogenic bacteria strains, using both spot on lawn qualitative method (on agar medium) and serial microdilution quantitative method (in broth medium). Further, it was evaluated the anti-biofilm activity of the tested samples toward the most important microbial strains implicated in biofilm development, using crystal violet stained biofilms microtiter assay, followed by spectrophotometric quantitative evaluation.

  15. Study of the structure of concrete with C-14-PMMA method

    NASA Astrophysics Data System (ADS)

    Muuri, E.; Tikkanen, O.; Ikonen, J.; Siitari-Kauppi, M.; Autio, M.

    2017-12-01

    Cement is used widely in the construction industry and, additionally, in the waste management industry for the stabilization of hazardous materials because of its capacity for both physical and chemical immobilization of contaminants. Cementitious materials have also been suggested as the backfilling materials, for example, in deep geological repositories for the final disposal of spent nuclear fuel. As a result, it is necessary to study the structure of the materials in different conditions. In this study, the structure of concrete was studied with the polymethylmetacrylate (PMMA) method in samples from the construction industry. The spatial distribution of porosity was characterized using this autoradiography method that involves the impregnation of a dried rock sample of hand specimen size with 14C-labelled methyl methacrylate (MMA) in vacuum, thermally initiated polymerization, film and digital autoradiography, and porosity calculation routines relying on digital image processing techniques [1]. Three main components are clearly visible on the PMMA autoradiographs of the studied concrete samples, because of their contrasted porosity (Fig 1.). Ground matrix cement shows even porosity; 27.0±4.7 %. The other two phases are mineral grains and bubbles, which are classified into four categories against their size and quantity. Fig 1. The scanned surface of the concrete sample (left) and the corresponding autoradiograph (right), where the darkest areas are caused by larger activity, and thus, larger porosity. The exposure time used for the autoradiogram was three days. J. Sammaljärvi, L. Jokelainen, J. Ikonen, M. Siitari-Kauppi, Eng. Geol. 135-136, 52-59 (2012).

  16. Acoustic Performance of Resilient Materials Using Acrylic Polymer Emulsion Resin.

    PubMed

    Kim, Haseog; Park, Sangki; Lee, Seahyun

    2016-07-19

    There have been frequent cases of civil complaints and disputes in relation to floor impact noises over the years. To solve these issues, a substantial amount of sound resilient material is installed between the concrete slab and the foamed concrete during construction. A new place-type resilient material is made from cement, silica powder, sodium sulfate, expanded-polystyrene, anhydrite, fly ash, and acrylic polymer emulsion resin. Its physical characteristics such as density, compressive strength, dynamic stiffness, and remanent strain are analyzed to assess the acoustic performance of the material. The experimental results showed the density and the dynamic stiffness of the proposed resilient material is increased with proportional to the use of cement and silica powder due to the high contents of the raw materials. The remanent strain, related to the serviceability of a structure, is found to be inversely proportional to the density and strength. The amount of reduction in the heavyweight impact noise is significant in a material with high density, high strength, and low remanent strain. Finally, specimen no. R4, having the reduction level of 3 dB for impact ball and 1 dB for bang machine in the single number quantity level, respectively, is the best product to obtain overall acoustic performance.

  17. Acoustic Performance of Resilient Materials Using Acrylic Polymer Emulsion Resin

    PubMed Central

    Kim, Haseog; Park, Sangki; Lee, Seahyun

    2016-01-01

    There have been frequent cases of civil complaints and disputes in relation to floor impact noises over the years. To solve these issues, a substantial amount of sound resilient material is installed between the concrete slab and the foamed concrete during construction. A new place-type resilient material is made from cement, silica powder, sodium sulfate, expanded-polystyrene, anhydrite, fly ash, and acrylic polymer emulsion resin. Its physical characteristics such as density, compressive strength, dynamic stiffness, and remanent strain are analyzed to assess the acoustic performance of the material. The experimental results showed the density and the dynamic stiffness of the proposed resilient material is increased with proportional to the use of cement and silica powder due to the high contents of the raw materials. The remanent strain, related to the serviceability of a structure, is found to be inversely proportional to the density and strength. The amount of reduction in the heavyweight impact noise is significant in a material with high density, high strength, and low remanent strain. Finally, specimen no. R4, having the reduction level of 3 dB for impact ball and 1 dB for bang machine in the single number quantity level, respectively, is the best product to obtain overall acoustic performance. PMID:28773711

  18. Additive Construction with Mobile Emplacement (ACME) / Automated Construction of Expeditionary Structures (ACES) Materials Delivery System (MDS)

    NASA Technical Reports Server (NTRS)

    Mueller, R. P.; Townsend, I. I.; Tamasy, G. J.; Evers, C. J.; Sibille, L. J.; Edmunson, J. E.; Fiske, M. R.; Fikes, J. C.; Case, M.

    2018-01-01

    The purpose of the Automated Construction of Expeditionary Structures, Phase 3 (ACES 3) project is to incorporate the Liquid Goods Delivery System (LGDS) into the Dry Goods Delivery System (DGDS) structure to create an integrated and automated Materials Delivery System (MDS) for 3D printing structures with ordinary Portland cement (OPC) concrete. ACES 3 is a prototype for 3-D printing barracks for soldiers in forward bases, here on Earth. The LGDS supports ACES 3 by storing liquid materials, mixing recipe batches of liquid materials, and working with the Dry Goods Feed System (DGFS) previously developed for ACES 2, combining the materials that are eventually extruded out of the print nozzle. Automated Construction of Expeditionary Structures, Phase 3 (ACES 3) is a project led by the US Army Corps of Engineers (USACE) and supported by NASA. The equivalent 3D printing system for construction in space is designated Additive Construction with Mobile Emplacement (ACME) by NASA.

  19. Sustainable Management of Construction and Demolition Materials

    EPA Pesticide Factsheets

    This web page discusses how to sustainably manage construction and demolition materials, Information covers, what they are, and how builders, construction crews, demolition teams,and deign practitioners can divert C&D from landfills.

  20. Pre-polishing on a CNC platform with bound abrasive contour tools

    NASA Astrophysics Data System (ADS)

    Schoeffer, Adrienne E.

    2003-05-01

    Deterministic micorgrinding (DMG) of optical glasses and ceramics is the commercial manufacturing process of choice to shape glass surfaces prior to final finishing. This process employs rigid bound matrix diamond tooling resulting in surface roughness values of 3-51.tm peak to valley and 100-400nm rms, as well as mid-spatial frequency tool marks that require subsequent removal in secondary finishing steps. The ability to pre-polish optical surfaces within the grinding platform would reduce final finishing process times. Bound abrasive contour wheels containing cerium oxide, alumina or zirconia abrasives were constructed with an epoxy matrix. The effects of abrasive type, composition, and erosion promoters were examined for tool hardness (Shore D), and tested with commercial optical glasses in an OptiproTM CNC grinding platform. Metrology protocols were developed to examine tool wear and subsequent surface roughness. Work is directed to demonstrating effective material removal, improved surface roughness and cutter mark removal.

  1. Prepolishing on a CNC platform with bound abrasive contour tools

    NASA Astrophysics Data System (ADS)

    Schoeffler, Adrienne E.; Gregg, Leslie L.; Schoen, John M.; Fess, Edward M.; Hakiel, Michael; Jacobs, Stephen D.

    2003-05-01

    Deterministic microgrinding (DMG) of optical glasses and ceramics is the commercial manufacturing process of choice to shape glass surfaces prior to final finishing. This process employs rigid bound matrix diamond tooling resulting in surface roughness values of 3-5μm peak to valley and 100-400nm rms, as well as mid-spatial frequency tool marks that require subsequent removal in secondary finishing steps. The ability to pre-polish optical surfaces within the grinding platform would reduce final finishing process times. Bound abrasive contour wheels containing cerium oxide, alumina or zirconia abrasives were constructed with an epoxy matrix. The effects of abrasive type, composition, and erosion promoters were examined for tool hardness (Shore D), and tested with commercial optical glasses in an Optipro CNC grinding platform. Metrology protocols were developed to examine tool wear and subsequent surface roughness. Work is directed to demonstrating effective material removal, improved surface roughness and cutter mark removal.

  2. Possible applications for municipal solid waste fly ash.

    PubMed

    Ferreira, C; Ribeiro, A; Ottosen, L

    2003-01-31

    The present study focuses on existing practices related to the reuse of Municipal Solid Waste (MSW) fly ash and identifies new potential uses. Nine possible applications were identified and grouped into four main categories: construction materials (cement, concrete, ceramics, glass and glass-ceramics); geotechnical applications (road pavement, embankments); "agriculture" (soil amendment); and, miscellaneous (sorbent, sludge conditioning). Each application is analysed in detail, including final-product technical characteristics, with a special emphasis on environmental impacts. A comparative analysis of the different options is performed, stressing the advantages but also the weaknesses of each option. This information is systemized in order to provide a framework for the selection of best technology and final products. The results presented here show new possibilities for this waste reuse in a short-term, in a wide range of fields, resulting in great advantages in waste minimization as well as resources conservation.

  3. Murine pluripotent stem cells derived scaffold-free cartilage grafts from a micro-cavitary hydrogel platform.

    PubMed

    He, Pengfei; Fu, Jiayin; Wang, Dong-An

    2016-04-15

    By means of appropriate cell type and scaffold, tissue-engineering approaches aim to construct grafts for cartilage repair. Pluripotent stem cells especially induced pluripotent stem cells (iPSCs) are of promising cell candidates due to the pluripotent plasticity and abundant cell source. We explored three dimensional (3D) culture and chondrogenesis of murine iPSCs (miPSCs) on an alginate-based micro-cavity hydrogel (MCG) platform in pursuit of fabricating synthetic-scaffold-free cartilage grafts. Murine embryonic stem cells (mESCs) were employed in parallel as the control. Chondrogenesis was fulfilled using a consecutive protocol via mesoderm differentiation followed by chondrogenic differentiation; subsequently, miPSC and mESC-seeded constructs were further respectively cultured in chondrocyte culture (CC) medium. Alginate phase in the constructs was then removed to generate a graft only comprised of induced chondrocytic cells and cartilaginous extracellular matrix (ECMs). We found that from the mESC-seeded constructs, formation of intact grafts could be achieved in greater sizes with relatively fewer chondrocytic cells and abundant ECMs; from miPSC-seeded constructs, relatively smaller sized cartilaginous grafts could be formed by cells with chondrocytic phenotype wrapped by abundant and better assembled collagen type II. This study demonstrated successful creation of pluripotent stem cells-derived cartilage/chondroid graft from a 3D MCG interim platform. By the support of materials and methodologies established from this study, particularly given the autologous availability of iPSCs, engineered autologous cartilage engraftment may be potentially fulfilled without relying on the limited and invasive autologous chondrocytes acquisition. In this study, we explored chondrogenic differentiation of pluripotent stem cells on a 3D micro-cavitary hydrogel interim platform and creation of pluripotent stem cells-derived cartilage/chondroid graft via a consecutive procedure. Our results demonstrated chondrogenic differentiation could be realized on the platform via mesoderm differentiation. The mESCs/miPSCs derived chondrocytic cells were further cultured to finally generate a pluripotent stem cells-derived scaffold-free construct based on the micro-cavitary hydrogel platform, in which alginate hydrogel could be removed finally. Our results showed that miPSC-derived graft could be formed by cells with chondrocytic phenotype wrapped by abundant and assembled collagen type II. To our knowledge, this study is the first study that initials from pluripotent stem cell seeding on 3D scaffold environment and ends with a scaffold-free chondrogenic micro-tissue. By the support of materials and methodologies established from this study, engineered autologous iPSC-derived cartilage engraftment may be potentially developed instead of autologous chondrocytes grafts that have limited source. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  4. Leaching behaviour of copper slag, construction and demolition waste and crushed rock used in a full-scale road construction.

    PubMed

    Lidelöw, Sofia; Mácsik, Josef; Carabante, Ivan; Kumpiene, Jurate

    2017-12-15

    The leaching behaviour of a road construction with fayalitic copper slag, recycled concrete and crushed rock as sub-base materials was monitored over ten years. All studied materials used in the road construction, including crushed rock, contained concentrations of several elements exceeding the guideline values recommended by the Swedish EPA for total element concentrations for waste materials used in constructions. Despite that, leaching from the road construction under field conditions in general was relatively low. The leachates from the recycled materials contained higher concentrations of several constituents than the leachates from the reference section with crushed rock. The leaching of the elements of interest (Cr, Mo, Ni, Zn) reached peak concentrations during the second and fourth (Cu) years and decreased over the observation period to levels below the Swedish recommended values. Carbonation of the concrete aggregates caused a substantial but short-term increase in the leaching of oxyanions such as chromate. The environmental risks related to element leaching are highest at the beginning of the road life. Ageing of materials or pre-treatment through leaching is needed prior to their use in construction to avoid peak concentrations. Also, the design of road constructions should be adjusted so that recycled materials are covered with low-permeability covers, which would minimize the exposure to atmospheric precipitation and weathering. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Greenhouse gas emissions during co-composting of calf mortalities with manure.

    PubMed

    Xu, Shanwei; Hao, Xiying; Stanford, Kim; McAllister, Tim A; Larney, Francis J; Wang, Jingguo

    2007-01-01

    Composting may be a viable on-farm option for disposal of cattle carcasses. This study investigated greenhouse gas emissions during co-composting of calf mortalities with manure. Windrows were constructed that contained manure + straw (control compost [CK]) or manure + straw + calf mortalities (CM) using two technologies: a tractor-mounted front-end loader or a shredder bucket. Composting lasted 289 d. The windrows were turned twice (on Days 72 and 190), using the same technology used in their creation. Turning technology had no effect on greenhouse gas emissions or the properties of the final compost. The CO2 (75.2 g d(-1) m(-2)), CH4 (2.503 g d(-1) m(-2)), and N2O (0.370 g d(-1) m(-2)) emissions were higher (p < 0.05) in CM than in CK (25.7, 0.094, and 0.076 g d(-1) m(-2) for CO2, CH4, and N2O, respectively), which reflected differences in materials used to construct the compost windrows and therefore their total C and total N contents. The final CM compost had higher (p < 0.05) total N, total C, and mineral N content (NO3*+ NO2* + NH4+) than did CK compost and therefore has greater agronomic value as a fertilizer.

  6. Investigation of New Materials and Methods of Construction of Personnel Armor

    DTIC Science & Technology

    2008-12-01

    NEW MATERIALS AND METHODS OF CONSTRUCTION OF PERSONNEL ARMOR by Poh, Choon Wei December 2008 Thesis Advisor: Robert S. Hixson Second...REPORT TYPE AND DATES COVERED Master’s Thesis 4. TITLE AND SUBTITLE Investigation of New Materials and Methods of Construction of Personnel Armor 6...personnel and vehicle armor. However, much of this work has focused on finding materials that were very ‘strong’ to resist penetration of objects moving

  7. A novel abutment construction technique for rapid bridge construction : controlled low strength Materials (CLSM) with full-height concrete panels.

    DOT National Transportation Integrated Search

    2012-01-01

    One of the major obstacles facing rapid bridge construction for typical span type bridges is the time required to construct bridge abutments and foundations. This can be remedied by using the controlled low strength materials (CLSM) bridge abutment. ...

  8. Agricultural Construction Volume I. Arc Welding Project Construction. Instructor's Guide.

    ERIC Educational Resources Information Center

    Brzozowski, Dick; Admire, Myron

    This guide contains instructor's materials for teaching a secondary agricultural construction course consisting of instructional units on arc welding (8 lessons) and project construction (14 lessons). The materials for each unit include student objectives, a list of competencies from which the objectives were derived, suggestions for motivating…

  9. Life Cycle Inventory (LCI) Data-Treatment Chemicals, Construction Materials, Transportation, On-site Equipment, and other Processes for Use in Spreadsheets for Environmental Footprint Analysis (SEFA): Revised Addition

    EPA Science Inventory

    This report estimates environmental emission factors (EmF) for key chemicals, construction and treatment materials, transportation/on-site equipment, and other processes used at remediation sites. The basis for chemical, construction, and treatment material EmFs is life cycle inv...

  10. 46 CFR 160.133-23 - Procedure for approval of design, material, or construction change.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 6 2014-10-01 2014-10-01 false Procedure for approval of design, material, or construction change. 160.133-23 Section 160.133-23 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Release Mechanisms for Lifeboats and Rescue Boats §...

  11. 46 CFR 160.135-23 - Procedure for approval of design, material, or construction change.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 6 2014-10-01 2014-10-01 false Procedure for approval of design, material, or construction change. 160.135-23 Section 160.135-23 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Lifeboats § 160.135-23 Procedure for approval of...

  12. 46 CFR 160.133-23 - Procedure for approval of design, material, or construction change.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 6 2013-10-01 2013-10-01 false Procedure for approval of design, material, or construction change. 160.133-23 Section 160.133-23 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Release Mechanisms for Lifeboats and Rescue Boats ...

  13. 46 CFR 160.156-23 - Procedure for approval of design, material, or construction change.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 6 2013-10-01 2013-10-01 false Procedure for approval of design, material, or construction change. 160.156-23 Section 160.156-23 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Rescue Boats and Fast Rescue Boats (SOLAS) § 160.156...

  14. 46 CFR 160.156-23 - Procedure for approval of design, material, or construction change.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 6 2014-10-01 2014-10-01 false Procedure for approval of design, material, or construction change. 160.156-23 Section 160.156-23 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Rescue Boats and Fast Rescue Boats (SOLAS) § 160.156...

  15. 46 CFR 160.135-23 - Procedure for approval of design, material, or construction change.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 6 2013-10-01 2013-10-01 false Procedure for approval of design, material, or construction change. 160.135-23 Section 160.135-23 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Lifeboats (SOLAS) § 160.135-23 Procedure for approva...

  16. Life Cycle Inventory (LCI) Data-Treatment Chemicals, Construction Materials, Transportation, On-site Equipment, and Other Processes for Use in Spreadsheets for Environmental Footprint Analysis (SEFA)

    EPA Science Inventory

    This report estimates environmental emission factors (EmF) for key chemicals, construction and treatment materials, transportation/on-site equipment, and other processes used at remediation sites. The basis for chemical, construction, and treatment material EmFs is life cycle inv...

  17. 46 CFR 177.1010 - Safety glazing materials.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... TONS) CONSTRUCTION AND ARRANGEMENT Window Construction and Visibility § 177.1010 Safety glazing materials. Glass and other glazing material used in windows accessible to passengers and crew must be of...

  18. Discriminative illumination: per-pixel classification of raw materials based on optimal projections of spectral BRDF.

    PubMed

    Liu, Chao; Gu, Jinwei

    2014-01-01

    Classifying raw, unpainted materials--metal, plastic, ceramic, fabric, and so on--is an important yet challenging task for computer vision. Previous works measure subsets of surface spectral reflectance as features for classification. However, acquiring the full spectral reflectance is time consuming and error-prone. In this paper, we propose to use coded illumination to directly measure discriminative features for material classification. Optimal illumination patterns--which we call "discriminative illumination"--are learned from training samples, after projecting to which the spectral reflectance of different materials are maximally separated. This projection is automatically realized by the integration of incident light for surface reflection. While a single discriminative illumination is capable of linear, two-class classification, we show that multiple discriminative illuminations can be used for nonlinear and multiclass classification. We also show theoretically that the proposed method has higher signal-to-noise ratio than previous methods due to light multiplexing. Finally, we construct an LED-based multispectral dome and use the discriminative illumination method for classifying a variety of raw materials, including metal (aluminum, alloy, steel, stainless steel, brass, and copper), plastic, ceramic, fabric, and wood. Experimental results demonstrate its effectiveness.

  19. 21 CFR 610.12 - Sterility.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... container material. (a) The test. Bulk material shall be tested separately from final container material and material from each final container shall be tested in individual test vessels as follows: (1) Using Fluid Thioglycollate Medium—(i) Bulk and final container material. The volume of product, as required by paragraph (d...

  20. Programming chemistry in DNA-addressable bioreactors.

    PubMed

    Fellermann, Harold; Cardelli, Luca

    2014-10-06

    We present a formal calculus, termed the chemtainer calculus, able to capture the complexity of compartmentalized reaction systems such as populations of possibly nested vesicular compartments. Compartments contain molecular cargo as well as surface markers in the form of DNA single strands. These markers serve as compartment addresses and allow for their targeted transport and fusion, thereby enabling reactions of previously separated chemicals. The overall system organization allows for the set-up of programmable chemistry in microfluidic or other automated environments. We introduce a simple sequential programming language whose instructions are motivated by state-of-the-art microfluidic technology. Our approach integrates electronic control, chemical computing and material production in a unified formal framework that is able to mimic the integrated computational and constructive capabilities of the subcellular matrix. We provide a non-deterministic semantics of our programming language that enables us to analytically derive the computational and constructive power of our machinery. This semantics is used to derive the sets of all constructable chemicals and supermolecular structures that emerge from different underlying instruction sets. Because our proofs are constructive, they can be used to automatically infer control programs for the construction of target structures from a limited set of resource molecules. Finally, we present an example of our framework from the area of oligosaccharide synthesis. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  1. Construction of a test embankment using a sand-tire shred mixture as fill material.

    PubMed

    Yoon, Sungmin; Prezzi, Monica; Siddiki, Nayyar Zia; Kim, Bumjoo

    2006-01-01

    Use of tire shreds in construction projects, such as highway embankments, is becoming an accepted way of beneficially recycling scrap tires. However, in the last decade there was a decline in the use of pure tire shreds as fill materials in embankment construction, as they are susceptible to fire hazards due to the development of exothermic reactions. Tire shred-sand mixtures, on the other hand, were found to be effective in inhibiting exothermic reactions. When compared with pure tire shreds, tire shred-sand mixtures are less compressible and have higher shear strength. However, the literature contains limited information on the use of tire shred-soil mixtures as a fill material. The objectives of this paper are to discuss and evaluate the feasibility of using tire shred-sand mixtures as a fill material in embankment construction. A test embankment constructed using a 50/50 mixture, by volume, of tire shreds and sand was instrumented and monitored to: (a) determine total and differential settlements; (b) evaluate the environmental impact of the embankment construction on the groundwater quality due to leaching of fill material; and (c) study the temperature variation inside the embankment. The findings in this research indicate that mixtures of tire shreds and sand are viable materials for embankment construction.

  2. Savannah River Plant engineering, design, and construction history of ``S`` projects and other work, January 1961--December 1964. Volume 2

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1970-03-01

    The work described in this volume of ``S`` Projects History is an extension of the type of work described in Volume I. E.I. du Pont de flemours & Company had entered into Contract AT (07-2)-l with the United States Atomic Energy Commission to develop, design, construct, install, and operate facilities to produce heavy water, fissionable materials, and related products. Under this contract,, Du Pont constructed and operated the Savannah River Plant. The engineering, design, and construction for most of the larger ``S`` projects was performed by the Engineering DeDartment. For some of the large and many of the smaller projectsmore » the Engineering Department was responsible only for the construction because the Atomic Energy Division (AED) of the Explosives Department handled the other phases. The Engineering Department Costruction Division also performed the physical work for many of the plant work orders. This volume includes a general description of the Du Pont Engineering Department activities pertaining to the engineering, design, and construction of the ``S`` projects at the Savannah River Plant; brief summaries of the projects and principal work requests; and supplementary informaticn on a few subjects in Volume I for which final data was not available at the closing date. Projects and other plant engineering work which were handled entirely by the Explosives Department -- AED are not included in this history.« less

  3. The status of LILW disposal facility construction in Korea

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kim, Min-Seok; Chung, Myung-Sub; Park, Kyu-Wan

    2013-07-01

    In this paper, we discuss the experiences during the construction of the first LILW disposal facility in South Korea. In December 2005, the South Korean Government designated Gyeongju-city as a host city of Low- and Intermediate-Level Radioactive Waste(LILW) disposal site through local referendums held in regions whose local governments had applied to host disposal facility in accordance with the site selection procedures. The LILW disposal facility is being constructed in Bongilri, Yangbuk-myeon, Gyeongju. The official name of the disposal facility is called 'Wolsong Low and Intermediate Level Radioactive Waste Disposal Center (LILW Disposal Center)'. It can dispose of 800,000 drumsmore » of radioactive wastes in a site of 2,100,000 square meters. At the first stage, LILW repository of underground silo type with disposal capacity of 100,000 drums is under construction expected to be completed by June of 2014. The Wolsong Low and Intermediate Level Radioactive Waste Disposal Center consists of surface facilities and underground facilities. The surface facilities include a reception and inspection facility, an interim storage facility, a radioactive waste treatment building, and supporting facilities such as main control center, equipment and maintenance shop. The underground facilities consist of a construction tunnel for transport of construction equipment and materials, an operation tunnel for transport of radioactive waste, an entrance shaft for workers, and six silos for final disposal of radioactive waste. As of Dec. 2012, the overall project progress rate is 93.8%. (authors)« less

  4. [Status of traditional Chinese medicine materials seed and seedling breeding bases].

    PubMed

    Li, Ying; Huang, Lu-Qi; Zhang, Xiao-Bo; Wang, Hui; Cheng, Meng; Zhang, Tian; Yang, Guang

    2017-11-01

    Seeds and seedlings are the material basis of traditional Chinese medicine materials production, and the construction of traditional Chinese medicine materials seed and seedling breeding bases is beneficial to the production of high-quality traditional Chinese medicine materials. The construction of traditional Chinese medicine materials seed and seedling breeding bases is one of the major topics of Chinese medica resources census pilot. Targets, tasks of traditional Chinese medicine materials seed and seedling breeding bases based on Chinese medica resources census pilot were expounded.Construction progress including hardware construction, germplasm conservation and breeding, procedures and standardsestablishment, social servicesare presented. Development counter measures were proposed for the next step: perfect the standard and system, maintain and strengthen the breeding function, strengthen the cultivation of multi-level talents, explore market development model, joint efforts to deepen services and development. Copyright© by the Chinese Pharmaceutical Association.

  5. 37. From Final Construction Report on the Haleakala Road ProjectNR7, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    37. From Final Construction Report on the Haleakala Road Project--NR-7, Hawaii National Park, Island of Maui, Territory of Hawaii. HAND-LAID ROCK BERM ON RETURN CURVE TO PREVENT SCOUR AND SEEPAGE THROUGH FILLS. - Haleakala National Park Roads, Pukalani, Maui County, HI

  6. 46 CFR 163.003-11 - Materials.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 6 2011-10-01 2011-10-01 false Materials. 163.003-11 Section 163.003-11 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL CONSTRUCTION Pilot Ladder § 163.003-11 Materials. (a) Suspension members. Each...

  7. 46 CFR 163.003-11 - Materials.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 6 2014-10-01 2014-10-01 false Materials. 163.003-11 Section 163.003-11 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL CONSTRUCTION Pilot Ladder § 163.003-11 Materials. (a) Suspension members. Each...

  8. 46 CFR 163.003-11 - Materials.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 6 2012-10-01 2012-10-01 false Materials. 163.003-11 Section 163.003-11 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL CONSTRUCTION Pilot Ladder § 163.003-11 Materials. (a) Suspension members. Each...

  9. 46 CFR 163.003-11 - Materials.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 6 2013-10-01 2013-10-01 false Materials. 163.003-11 Section 163.003-11 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL CONSTRUCTION Pilot Ladder § 163.003-11 Materials. (a) Suspension members. Each...

  10. 46 CFR 160.036-3 - Materials, workmanship, construction and performance requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Hand-Held Rocket... performance requirements. (a) Materials. The materials used in handheld rocket-propelled parachute red flare... protected against corrosion. (b) Workmanship. Handheld rocket-propelled parachute red flare distress signals...

  11. 46 CFR 160.036-3 - Materials, workmanship, construction and performance requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Hand-Held Rocket... performance requirements. (a) Materials. The materials used in handheld rocket-propelled parachute red flare... protected against corrosion. (b) Workmanship. Handheld rocket-propelled parachute red flare distress signals...

  12. 46 CFR 160.036-3 - Materials, workmanship, construction and performance requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Hand-Held Rocket... performance requirements. (a) Materials. The materials used in handheld rocket-propelled parachute red flare... protected against corrosion. (b) Workmanship. Handheld rocket-propelled parachute red flare distress signals...

  13. 46 CFR 160.036-3 - Materials, workmanship, construction and performance requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Hand-Held Rocket... performance requirements. (a) Materials. The materials used in handheld rocket-propelled parachute red flare... protected against corrosion. (b) Workmanship. Handheld rocket-propelled parachute red flare distress signals...

  14. 46 CFR 160.036-3 - Materials, workmanship, construction and performance requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Hand-Held Rocket... performance requirements. (a) Materials. The materials used in handheld rocket-propelled parachute red flare... protected against corrosion. (b) Workmanship. Handheld rocket-propelled parachute red flare distress signals...

  15. Delivery of Fuel and Construction Materials to South Pole Station

    DTIC Science & Technology

    1993-07-01

    AID-A270 431 Delivery of Fuel and Construction Materials to South Pole Station Stephen L. DenHartog and George L. Blaisdell July 993 DTIC ELECT S OCT...South Pole Station, ideally with minimal impact on the current science and operational program. The new station will require the delivery of massive...amounts of construction materials to this remote site. The existing means of delivering material and fuel to the South Pole include the use of specialized

  16. Under construction: building a safer industry.

    PubMed Central

    Tibbetts, John

    2002-01-01

    A revolution in the building industry over the past decade has spawned a new generation of safer materials and practices, decreasing some health risks for construction workers. Concerned consumers, builders, materials manufacturers, and government regulatory agencies have all contributed to a turn toward "green" building materials and practices, meaning that homeowners and office workers now are better able to live and work in healthier environments, and many construction workers are handling and installing less-toxic materials. PMID:11882489

  17. Recycled industrial and construction waste for mutual beneficial use.

    DOT National Transportation Integrated Search

    2016-08-01

    Instead of going to landfills, certain waste materials from industry and building construction can be recycled in transportation infrastructure projects, such as roadway paving. The beneficial use of waste materials in the construction of transportat...

  18. A Deliberate Practice Approach to Teaching Phylogenetic Analysis

    PubMed Central

    Hobbs, F. Collin; Johnson, Daniel J.; Kearns, Katherine D.

    2013-01-01

    One goal of postsecondary education is to assist students in developing expert-level understanding. Previous attempts to encourage expert-level understanding of phylogenetic analysis in college science classrooms have largely focused on isolated, or “one-shot,” in-class activities. Using a deliberate practice instructional approach, we designed a set of five assignments for a 300-level plant systematics course that incrementally introduces the concepts and skills used in phylogenetic analysis. In our assignments, students learned the process of constructing phylogenetic trees through a series of increasingly difficult tasks; thus, skill development served as a framework for building content knowledge. We present results from 5 yr of final exam scores, pre- and postconcept assessments, and student surveys to assess the impact of our new pedagogical materials on student performance related to constructing and interpreting phylogenetic trees. Students improved in their ability to interpret relationships within trees and improved in several aspects related to between-tree comparisons and tree construction skills. Student feedback indicated that most students believed our approach prepared them to engage in tree construction and gave them confidence in their abilities. Overall, our data confirm that instructional approaches implementing deliberate practice address student misconceptions, improve student experiences, and foster deeper understanding of difficult scientific concepts. PMID:24297294

  19. Introduction to Construction Welding. Instructor Edition. Introduction to Construction Series.

    ERIC Educational Resources Information Center

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This instructor's guide contains the materials required to teach a competency-based introductory course in construction welding to students who have chosen to explore careers in construction. It contains three units: welding materials, welding tools, and applied skills. Each instructional unit includes some or all of the basic components of a unit…

  20. 19 CFR 123.18 - Equipment and materials for constructing bridges or tunnels between the United States and Canada...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Equipment and materials for constructing bridges... bridges or tunnels between the United States and Canada or Mexico. (a) Admission of equipment and materials. Equipment for use in construction of bridges or tunnels between the United States and Canada or...

  1. Auditing of suppliers as the requirement of quality management systems in construction

    NASA Astrophysics Data System (ADS)

    Harasymiuk, Jolanta; Barski, Janusz

    2017-07-01

    The choice of a supplier of construction materials can be important factor of increase or reduction of building works costs. Construction materials present from 40 for 70% of investment task depending on kind of works being provided for realization. There is necessity of estimate of suppliers from the point of view of effectiveness of construction undertaking and necessity from the point of view of conformity of taken operation by executives of construction job and objects within the confines of systems of managements quality being initiated in their organizations. The estimate of suppliers of construction materials and subexecutives of special works is formal requirement in quality management systems, which meets the requirements of the ISO 9001 standard. The aim of this paper is to show possibilities of making use of anaudit for estimate of credibility and reliability of the supplier of construction materials. The article describes kinds of audits, that were carried in quality management systems, with particular taking into consideration audits called as second-site. One characterizes the estimate criterions of qualitative ability and method of choice of the supplier of construction materials. The paper shows also propositions of exemplary questions, that would be estimated in audit process, the way of conducting of this estimate and conditionality of estimate.

  2. Using reclaimed lumber and wood flooring in construction : measuring environmental impact using life-cycle inventory analysis

    Treesearch

    Richard D. Bergman; Hongmei Gu; Robert H. Falk; Thomas R. Napier

    2010-01-01

    With green building concepts becoming widespread in the construction field, building practices and materials are being examined for their environmental impact. Reusing building materials has a distinct advantage over using newly manufactured materials because these reclaimed materials avoid greenhouse gas emissions associated with new (virgin) material manufacturing....

  3. In-situ resource utilization in the design of advanced lunar facilities

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Resource utilization will play an important role in the establishment and support of a permanently manned lunar base. At the University of Houston - College of Architecture and the Sasakawa International Center for Space Architecture, a study team recently investigated the potential use of lunar in-situ materials in the design of lunar facilities. The team identified seven potential lunar construction materials; concrete, sulfur concrete, cast basalt, sintered basalt, glass, fiberglass, and metals. Analysis and evaluation of these materials with respect to their physical properties, processes, energy requirements, resource efficiency, and overall advantages and disadvantages lead to the selection of basalt materials as the more likely construction material for initial use on a lunar base. Basalt materials can be formed out of in-situ lunar regolith, with minor material beneficiation, by a simple process of heating and controlled cooling. The team then conceptualized a construction system that combines lunar regolith sintering and casting to make pressurized structures out of lunar resources. The design uses a machine that simultaneously excavates and sinters the lunar regolith to create a cylindrical hole, which is then enclosed with cast basalt slabs, allowing the volume to be pressurized for use as a living or work environment. Cylinder depths of up to 4 to 6 m in the lunar mare or 10 to 12 m in the lunar highlands are possible. Advantages of this construction system include maximum resource utilization, relatively large habitable volumes, interior flexibility, and minimal construction equipment needs. Conclusions of this study indicate that there is significant potential for the use of basalt, a lunar resource derived construction material, as a low cost alternative to Earth-based materials. It remains to be determined when in lunar base phasing this construction method should be implemented.

  4. Substandard Materials for Pavement Construction

    DTIC Science & Technology

    1988-09-01

    aggregates, dure sands and coastal deposits, shales, laterite gravels, and duricrusts are reviewed in this paper. These substandard materials may also...16 Laterite gravels ................... .......................... 18 Duricrusts ...ability to predict field performance. Other construction materials such as laterites or cemented materials such as duricrusts are difficult to analyze

  5. 39. From Final Construction Report on the Haleakala Road ProjectNR7, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    39. From Final Construction Report on the Haleakala Road Project--NR-7, Hawaii National Park, Island of Maui, Territory of Hawaii, T.H., by Merel S. Sager, Resident Landscape Architect, April 16, 1935. COVERING CONSPICOUS ROCK FILLS WITH SOIL. - Haleakala National Park Roads, Pukalani, Maui County, HI

  6. 24 CFR 242.52 - Construction contracts.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...; a construction management contract with a guaranteed maximum price, the final costs of which are... 24 Housing and Urban Development 2 2013-04-01 2013-04-01 false Construction contracts. 242.52... MORTGAGE INSURANCE FOR HOSPITALS Construction § 242.52 Construction contracts. (a) Awarding of contract. A...

  7. Comparative evaluation of low cost materials as constructed wetland filling media

    NASA Astrophysics Data System (ADS)

    Pinho, Henrique J. O.; Vaz, Mafalda M.; Mateus, Dina M. R.

    2017-11-01

    Three waste materials from civil construction activities were assessed as low cost alternative filling materials used in Constructed Wetlands (CW). CW are green processes for wastewater treatment, whose design includes an appropriate selection of vegetation and filling material. The sustainability of such processes may be incremented using recovered wastes as filling materials. The abilities of the materials to support plant growth and to contribute to pollutants removal from wastewater were assessed and compared to expanded clay, a filling usually used in CW design. Statistical analysis, using one-way ANOVA and Welch's ANOVA, demonstrate that limestone fragments are a better choice of filling material than brick fragments and basalt gravel.

  8. Evaluation of fuel usage factors in highway construction in Oregon.

    DOT National Transportation Integrated Search

    2010-05-01

    Prices for different construction materials change frequently. In recent years, the price for these different materials has dramatically increased. This result leads contractors to inflate the bid price for a construction project in order to cover th...

  9. Fibrin gels exhibit improved biological, structural, and mechanical properties compared with collagen gels in cell-based tendon tissue-engineered constructs.

    PubMed

    Breidenbach, Andrew P; Dyment, Nathaniel A; Lu, Yinhui; Rao, Marepalli; Shearn, Jason T; Rowe, David W; Kadler, Karl E; Butler, David L

    2015-02-01

    The prevalence of tendon and ligament injuries and inadequacies of current treatments is driving the need for alternative strategies such as tissue engineering. Fibrin and collagen biopolymers have been popular materials for creating tissue-engineered constructs (TECs), as they exhibit advantages of biocompatibility and flexibility in construct design. Unfortunately, a few studies have directly compared these materials for tendon and ligament applications. Therefore, this study aims at determining how collagen versus fibrin hydrogels affect the biological, structural, and mechanical properties of TECs during formation in vitro. Our findings show that tendon and ligament progenitor cells seeded in fibrin constructs exhibit improved tenogenic gene expression patterns compared with their collagen-based counterparts for approximately 14 days in culture. Fibrin-based constructs also exhibit improved cell-derived collagen alignment, increased linear modulus (2.2-fold greater) compared with collagen-based constructs. Cyclic tensile loading, which promotes the maturation of tendon constructs in a previous work, exhibits a material-dependent effect in this study. Fibrin constructs show trending reductions in mechanical, biological, and structural properties, whereas collagen constructs only show improved tenogenic expression in the presence of mechanical stimulation. These findings highlight that components of the mechanical stimulus (e.g., strain amplitude or time of initiation) need to be tailored to the material and cell type. Given the improvements in tenogenic expression, extracellular matrix organization, and material properties during static culture, in vitro findings presented here suggest that fibrin-based constructs may be a more suitable alternative to collagen-based constructs for tissue-engineered tendon/ligament repair.

  10. Fibrin Gels Exhibit Improved Biological, Structural, and Mechanical Properties Compared with Collagen Gels in Cell-Based Tendon Tissue-Engineered Constructs

    PubMed Central

    Dyment, Nathaniel A.; Lu, Yinhui; Rao, Marepalli; Shearn, Jason T.; Rowe, David W.; Kadler, Karl E.; Butler, David L.

    2015-01-01

    The prevalence of tendon and ligament injuries and inadequacies of current treatments is driving the need for alternative strategies such as tissue engineering. Fibrin and collagen biopolymers have been popular materials for creating tissue-engineered constructs (TECs), as they exhibit advantages of biocompatibility and flexibility in construct design. Unfortunately, a few studies have directly compared these materials for tendon and ligament applications. Therefore, this study aims at determining how collagen versus fibrin hydrogels affect the biological, structural, and mechanical properties of TECs during formation in vitro. Our findings show that tendon and ligament progenitor cells seeded in fibrin constructs exhibit improved tenogenic gene expression patterns compared with their collagen-based counterparts for approximately 14 days in culture. Fibrin-based constructs also exhibit improved cell-derived collagen alignment, increased linear modulus (2.2-fold greater) compared with collagen-based constructs. Cyclic tensile loading, which promotes the maturation of tendon constructs in a previous work, exhibits a material-dependent effect in this study. Fibrin constructs show trending reductions in mechanical, biological, and structural properties, whereas collagen constructs only show improved tenogenic expression in the presence of mechanical stimulation. These findings highlight that components of the mechanical stimulus (e.g., strain amplitude or time of initiation) need to be tailored to the material and cell type. Given the improvements in tenogenic expression, extracellular matrix organization, and material properties during static culture, in vitro findings presented here suggest that fibrin-based constructs may be a more suitable alternative to collagen-based constructs for tissue-engineered tendon/ligament repair. PMID:25266738

  11. Final Report. LAW Glass Formulation to Support AP-101 Actual Waste Testing, VSL-03R3470-2, Rev. 0

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Muller, I. S.; Pegg, I. L.; Rielley, Elizabeth

    2015-06-22

    The main objective of the work was to develop and select a glass formulation for vitrification testing of the actual waste sample of LAW AP-101 at Battelle - Pacific Northwest Division (PNWD). Other objectives of the work included preparation and characterization of glasses to demonstrate compliance with contract and processing requirements, evaluation of the ability to achieve waste loading requirements, testing to demonstrate compatibility of the glass melts with melter materials of construction, comparison of the properties of simulant and actual waste glasses, and identification of glass formulation issues with respect to contract specifications and processing requirements.

  12. Final Report. Baseline LAW Glass Formulation Testing, VSL-03R3460-1, Rev. 0

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Muller, Isabelle S.; Pegg, Ian L.; Gan, Hao

    2015-06-18

    The major objective of the baseline glass formulation work was to develop and select glass formulations that are compliant with contractual and processing requirements for each of the LAW waste streams. Other objectives of the work included preparation and characterization of glasses with respect to the properties of interest, optimization of sulfate loading in the glasses, evaluation of ability to achieve waste loading limits, testing to demonstrate compatibility of glass melts with melter materials of construction, development of glass formulations to support ILAW qualification activities, and identification of glass formulation issues with respect to contract specifications and processing requirements.

  13. A Millimeter Wave BPF using WG Mode High Permittivity Dielectric Resonators

    NASA Astrophysics Data System (ADS)

    Sato, Yosuke; Kogami, Yoshinori; Tomabechi, Yoshiro; Matsumura, Kazuhito

    In this paper, a design technique of whispering gallery mode high Q value dielectric disk resonators for a millimeter-wave bandpass filter is described. To minimize the resonator size, some high permittivity materials are used. In this resonator design, unloaded Q value of an interested mode and the higher order modes are calculated and then optimum resonator size for the WG mode dielectric filter is determined. For a designed resonator, the higher order modes are hardly excited while the Q value of the fundamental mode can be maximized. Finally, some 3stage BPFs are constructed at 60GHz by using these designed resonators.

  14. Role of carbon nanotubes in electroanalytical chemistry: a review.

    PubMed

    Agüí, Lourdes; Yáñez-Sedeño, Paloma; Pingarrón, José M

    2008-08-01

    This review covers recent advances in the development of new designs of electrochemical sensors and biosensors that make use of electrode surfaces modification with carbon nanotubes. Applications based on carbon nanotubes-driven electrocatalytic effects, and the construction and analytical usefulness of new hybrid materials with polymers or other nanomaterials will be treated. Moreover, electrochemical detection using carbon nanotubes-modified electrodes as detecting systems in separation techniques such as high performance liquid chromatography (HPLC) or capillary electrophoresis (CE) will be also considered. Finally, the preparation of electrochemical biosensors, including enzyme electrodes, immunosensors and DNA biosensors, in which carbon nanotubes play a significant role in their sensing performance will be separately considered.

  15. Final Environmental Assessment: Addressing Construction of a New Civil Engineering Workshop at Bellows Air Force Station, O’ahu, Hawaii

    DTIC Science & Technology

    2010-03-01

    FINAL ENVIRONMENTAL ASSESSMENT ADDRESSING CONSTRUCTION OF A NEW CIVIL ENGINEERING WORKSHOP AT BELLOWS AIR FORCE STATION , O‘AHU, HAWAI‘I...Minimize impacts on other Bellows AFS functions and environmental resources This alternative would be located in an area located near Building 546 and...Preparation of An Environmental Assessment for the Proposed Construction of New Civil Engineering Workshop at Bellows Air !Force Station Thank you

  16. 46 CFR 160.047-3 - Materials.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 6 2011-10-01 2011-10-01 false Materials. 160.047-3 Section 160.047-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS... and Child § 160.047-3 Materials. (a) General. All components used in the construction of buoyant vests...

  17. The Historical Evolution of Dental Impression Materials.

    PubMed

    Papadiochos, Ioannis; Papadiochou, Sofia; Emmanouil, Ioannis

    The concept of impression making process in dentistry began in the mid 1800s. Dentists realized that the construction of a prosthetic restoration required both a detailed capture of the oral tissues along with stone cast fabrications. To accomplish these goals, impression materials were essential. Beeswax represents the first impression material, while important bechmarks during the historical evolution of dental impression materials are considered to be the introduction of dental trays in the early 1800s and the invention of the gutta-percha, thermoplastic resins and plaster of Paris. The double (corrective) impression technique, along with the functional impression concept that was established after mid 1800s, are also identified as pivotal innovations. During the 20th century, the advances in material development slowed significantly since the majority of the current impression materials had already been invented. However, the introduction of elastomeric impression materials in the field of prosthodontics that offered the advantages of accuracy and dimensional stability substantially upgraded both the impression accuracy and the quality of the final restoration. Presently, the dental practitioner has access to a variety of impression materials and should be aware of their properties, indications and limitations as well. Futhermore, while continuous attempts are being made to enhance these materials, the ideal impression material has yet to be developed. The purpose of this article was to provide a comprehensive review about the historical development of impression dental materials. Copyright American Academy of the History of Dentistry.

  18. 48 CFR 225.7501 - Policy.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... only domestic end products for use outside the United States, and use only domestic construction material for construction to be performed outside the United States, including end products and... simplified acquisition threshold; (2) The end product or particular construction material is— (i) Listed in...

  19. 48 CFR 225.7501 - Policy.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... only domestic end products for use outside the United States, and use only domestic construction material for construction to be performed outside the United States, including end products and... simplified acquisition threshold; (2) The end product or particular construction material is— (i) Listed in...

  20. 48 CFR 225.7501 - Policy.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... only domestic end products for use outside the United States, and use only domestic construction material for construction to be performed outside the United States, including end products and... simplified acquisition threshold; (2) The end product or particular construction material is— (i) Listed in...

  1. 48 CFR 225.7501 - Policy.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... only domestic end products for use outside the United States, and use only domestic construction material for construction to be performed outside the United States, including end products and... simplified acquisition threshold; (2) The end product or particular construction material is— (i) Listed in...

  2. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kim, Jae Wook; Artyukhin, Sergei; Mun, Eun Deok

    In this paper, we report the discovery of a metamagnetic phase transition in a polar antiferromagnet Ni 3TeO 6 that occurs at 52 T. The new phase transition accompanies a colossal magnetoelectric effect, with a magnetic-field-induced polarization change of 0.3 μC/cm 2, a value that is 4 times larger than for the spin-flop transition at 9 T in the same material, and also comparable to the largest magnetically induced polarization changes observed to date. Via density-functional calculations we construct a full microscopic model that describes the data. We model the spin structures in all fields and clarify the physics behindmore » the 52 T transition. The high-field transition involves a competition between multiple different exchange interactions which drives the polarization change through the exchange-striction mechanism. Finally, the resultant spin structure is rather counterintuitive and complex, thus providing new insights on design principles for materials with strong magnetoelectric coupling.« less

  3. Pulsed ion beam source

    DOEpatents

    Greenly, John B.

    1997-01-01

    An improved pulsed ion beam source having a new biasing circuit for the fast magnetic field. This circuit provides for an initial negative bias for the field created by the fast coils in the ion beam source which pre-ionize the gas in the source, ionize the gas and deliver the gas to the proper position in the accelerating gap between the anode and cathode assemblies in the ion beam source. The initial negative bias improves the interaction between the location of the nulls in the composite magnetic field in the ion beam source and the position of the gas for pre-ionization and ionization into the plasma as well as final positioning of the plasma in the accelerating gap. Improvements to the construction of the flux excluders in the anode assembly are also accomplished by fabricating them as layered structures with a high melting point, low conductivity material on the outsides with a high conductivity material in the center.

  4. Construction of the 16 meter Large Lunar Telescope (LLT)

    NASA Technical Reports Server (NTRS)

    Omar, Husam Anwar

    1990-01-01

    The different materials that could be used to design the pedestal for a Moon based 16 meter telescope are discussed. The material that should be used has a low coefficient of thermal expansion, high modulus of elasticity, and high compressive and tensile strengths. For the model developed in this study, an aluminum-manganese alloy was used because of its low coefficient of thermal expansion. Due to variations in lunar soil conditions, both vertically and horizontally, three foundation systems are presented. The spudcan footing can be used in the case where dense soil is more than three meters. The spread footing is recommended where the dense soil is between one and three meters. Finally, in the third system, the Lunar Excursion Vehicle (LEV) is used as a base support for the telescope's pedestal. The LEV support requires a prepared site. The soil should be compacted and stabilized, if necessary, to reduce settlement.

  5. Report of the In Situ Resources Utilization Workshop

    NASA Technical Reports Server (NTRS)

    Fairchild, Kyle (Editor); Mendell, Wendell W. (Editor)

    1988-01-01

    The results of a workshop of 50 representatives from the public and private sector which investigated the potential joint development of the key technologies and mechanisms that will enable the permanent habitation of space are presented. The workshop is an initial step to develop a joint public/private assessment of new technology requirements of future space options, to share knowledge on required technologies that may exist in the private sector, and to investigate potential joint technology development opportunities. The majority of the material was produced in 5 working groups: (1) Construction, Assembly, Automation and Robotics; (2) Prospecting, Mining, and Surface Transportation; (3) Biosystems and Life Support; (4) Materials Processing; and (5) Innovative Ventures. In addition to the results of the working groups, preliminary technology development recommendations to assist in near-term development priority decisions are presented. Finally, steps are outlined for potential new future activities and relationships among the public, private, and academic sectors.

  6. Parametric study using modal analysis of a bi-material plate with defects

    NASA Astrophysics Data System (ADS)

    Esola, S.; Bartoli, I.; Horner, S. E.; Zheng, J. Q.; Kontsos, A.

    2015-03-01

    Global vibrational method feasibility as a non-destructive inspection tool for multi-layered composites is evaluated using a simulated parametric study approach. A finite element model of a composite consisting of two, isotropic layers of dissimilar materials and a third, thin isotropic layer of adhesive is constructed as the representative test subject. Next, artificial damage is inserted according to systematic variations of the defect morphology parameters. A free-vibrational modal analysis simulation is executed for pristine and damaged plate conditions. Finally, resultant mode shapes and natural frequencies are extracted, compared and analyzed for trends. Though other defect types may be explored, the focus of this research is on interfacial delamination and its effects on the global, free-vibrational behavior of a composite plate. This study is part of a multi-year research effort conducted for the U.S. Army Program Executive Office - Soldier.

  7. Principles of Genetic Circuit Design

    PubMed Central

    Brophy, Jennifer A.N.; Voigt, Christopher A.

    2014-01-01

    Cells are able to navigate environments, communicate, and build complex patterns by initiating gene expression in response to specific signals. Engineers need to harness this capability to program cells to perform tasks or build chemicals and materials that match the complexity seen in nature. This review describes new tools that aid the construction of genetic circuits. We show how circuit dynamics can be influenced by the choice of regulators and changed with expression “tuning knobs.” We collate the failure modes encountered when assembling circuits, quantify their impact on performance, and review mitigation efforts. Finally, we discuss the constraints that arise from operating within a living cell. Collectively, better tools, well-characterized parts, and a comprehensive understanding of how to compose circuits are leading to a breakthrough in the ability to program living cells for advanced applications, from living therapeutics to the atomic manufacturing of functional materials. PMID:24781324

  8. Options and recommendations for a web database of material and construction inspection.

    DOT National Transportation Integrated Search

    2015-02-01

    The Illinois Department of Transportation (IDOT) has been using software developed in-house for their : materials management and construction project management needs. The primary packages under : review MISTIC (Materials Management) and ICORS (Const...

  9. Usage of Alternative, Environmentally Acceptable Materials—Experience from Eastern Croatia

    NASA Astrophysics Data System (ADS)

    Barišić, I.; Zagvozda, M.; Dimter, S.

    2015-11-01

    The concept of sustainability should be the main guiding principle in the construction industry today. It mandates conservation of natural resources and thus lower impact on the environment. In road construction, part of construction industry that consumes largest quantities of natural materials, sustainable building and maintenance of roads is possible trough application of secondary materials. Usage of industrial and construction waste presents energy, ecologically and financially effective alternative. Republic of Croatia, even as a new member of the European Union, still lags behind the well-established practices of the application of alternative materials in different European countries. The reasons for this can be found in the current legal and technical regulations for alternative materials. In this paper, the existing regulations for alternative materials and the impact they have on the application of these materials in practice in the region of eastern Croatia will be shown.

  10. THE CAST PAPER DOME: AN OPPORTUNITY TO DEVELOP NEW MATERIALS AND CONSTRUCTION TECHNIQUES FOR SUSTAINABLE BUILDING

    EPA Science Inventory

    Hundreds, and sometimes thousands, of years of architectural design and construction practice have reduced our materials options to only the strongest materials, put together in the strongest way. It is difficult for current practitioners to use sustainably produced materials...

  11. Experimental measurements and finite element models of High Displacement Piezoelectric Actuators.

    NASA Astrophysics Data System (ADS)

    Camargo, Gilberto; Ashford, Gevale; Naco, Eris; Usher, Tim

    2004-03-01

    Piezoelectric actuators have many applications including morphable wing technology and piezoelectric transformers. A Piezoelectric ceramic is a material that will move when a voltage is applied and conversely produces a charge when a pressure is applied. In our study, we examine THUNDER (Thin Layer Unimorph Ferroelectric Driver and Sensor) actuators (Thunder TM is a trademark of FACE International Corporation.) Thunder actuators are constructed by bonding thin PZT piezoelectric ceramics to metal sheets. We will present physical measurements of piezoelectric actuators, as well as measurements of the displacements due to applied voltages. In our studies we used a laser micrometer to measure the dimensional characteristics of four sizes of THUNDER actuators including TH-8R, TH-9R, TH-10R, and finally the TH-11R. We also developed computer models using a commercial fine element modeling package (FEM) known as ANSYS6.0®. This software enables us to construct our models controlling such attributes as exact dimensions of the three layers of the piezoelectric actuator, the material properties of each element, the type of load that is to be applied as well as the manner in which the layers are bonded together. The computer model compares favorably with the experimental results. Acknowledgements: NASA Grant No. 0051-0078 Department of Defense (DoD) Control No.ISP02-EUG15

  12. Category-Specific Neural Oscillations Predict Recall Organization During Memory Search

    PubMed Central

    Morton, Neal W.; Kahana, Michael J.; Rosenberg, Emily A.; Baltuch, Gordon H.; Litt, Brian; Sharan, Ashwini D.; Sperling, Michael R.; Polyn, Sean M.

    2013-01-01

    Retrieved-context models of human memory propose that as material is studied, retrieval cues are constructed that allow one to target particular aspects of past experience. We examined the neural predictions of these models by using electrocorticographic/depth recordings and scalp electroencephalography (EEG) to characterize category-specific oscillatory activity, while participants studied and recalled items from distinct, neurally discriminable categories. During study, these category-specific patterns predict whether a studied item will be recalled. In the scalp EEG experiment, category-specific activity during study also predicts whether a given item will be recalled adjacent to other same-category items, consistent with the proposal that a category-specific retrieval cue is used to guide memory search. Retrieved-context models suggest that integrative neural circuitry is involved in the construction and maintenance of the retrieval cue. Consistent with this hypothesis, we observe category-specific patterns that rise in strength as multiple same-category items are studied sequentially, and find that individual differences in this category-specific neural integration during study predict the degree to which a participant will use category information to organize memory search. Finally, we track the deployment of this retrieval cue during memory search: Category-specific patterns are stronger when participants organize their responses according to the category of the studied material. PMID:22875859

  13. 77 FR 26763 - General Services Administration Acquisition Regulation; Submission for OMB Review; Contract...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-07

    ... Claims, regarding final payment under construction and building services contract. GSA Form 1142 was... construction and building services contractors to submit a release of claims before final payment is made to... (GSAR Parts 532 and 552.232-72; GSA Form 1142 Release of Claims) AGENCY: Office of the Chief Acquisition...

  14. 40 CFR 62.14565 - How do I comply with the increment of progress for achieving final compliance?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... DESIGNATED FACILITIES AND POLLUTANTS Federal Plan Requirements for Commercial and Industrial Solid Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Compliance Schedule and... complete retrofit construction of control devices, as specified in the final control plan, so that, when...

  15. Beyond the material grave: Life Cycle Impact Assessment of leaching from secondary materials in road and earth constructions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schwab, Oliver; Karlsruhe Institute of Technology, Institute for Geography and Geoecology, Adenauerring 20, 76131 Karlsruhe; Bayer, Peter, E-mail: bayer@erdw.ethz.ch

    Highlights: • We model environmental impacts of leaching from secondary construction material. • Industrial wastes in construction contain up to 45,000 t heavy metals per year (D). • In a scenario, 150 t are leached to the environment within 100 years after construction. • All heavy metals but As, Sb and Mo are adsorbed by 20 cm subsoil in this scenario. • Environmental impacts depend on material, pollutant, construction type, and geography. - Abstract: In industrialized countries, large amounts of mineral wastes are produced. They are re-used in various ways, particularly in road and earth constructions, substituting primary resources suchmore » as gravel. However, they may also contain pollutants, such as heavy metals, which may be leached to the groundwater. The toxic impacts of these emissions are so far often neglected within Life Cycle Assessments (LCA) of products or waste treatment services and thus, potentially large environmental impacts are currently missed. This study aims at closing this gap by assessing the ecotoxic impacts of heavy metal leaching from industrial mineral wastes in road and earth constructions. The flows of metals such as Sb, As, Pb, Cd, Cr, Cu, Mo, Ni, V and Zn originating from three typical constructions to the environment are quantified, their fate in the environment is assessed and potential ecotoxic effects evaluated. For our reference country, Germany, the industrial wastes that are applied as Granular Secondary Construction Material (GSCM) carry more than 45,000 t of diverse heavy metals per year. Depending on the material quality and construction type applied, up to 150 t of heavy metals may leach to the environment within the first 100 years after construction. Heavy metal retardation in subsoil can potentially reduce the fate to groundwater by up to 100%. One major challenge of integrating leaching from constructions into macro-scale LCA frameworks is the high variability in micro-scale technical and geographical factors, such as material qualities, construction types and soil types. In our work, we consider a broad range of parameter values in the modeling of leaching and fate. This allows distinguishing between the impacts of various road constructions, as well as sites with different soil properties. The findings of this study promote the quantitative consideration of environmental impacts of long-term leaching in Life Cycle Assessment, complementing site-specific risk assessment, for the design of waste management strategies, particularly in the construction sector.« less

  16. Life Cycle Assessment of Wall Systems

    NASA Astrophysics Data System (ADS)

    Ramachandran, Sriranjani

    Natural resource depletion and environmental degradation are the stark realities of the times we live in. As awareness about these issues increases globally, industries and businesses are becoming interested in understanding and minimizing the ecological footprints of their activities. Evaluating the environmental impacts of products and processes has become a key issue, and the first step towards addressing and eventually curbing climate change. Additionally, companies are finding it beneficial and are interested in going beyond compliance using pollution prevention strategies and environmental management systems to improve their environmental performance. Life-cycle Assessment (LCA) is an evaluative method to assess the environmental impacts associated with a products' life-cycle from cradle-to-grave (i.e. from raw material extraction through to material processing, manufacturing, distribution, use, repair and maintenance, and finally, disposal or recycling). This study focuses on evaluating building envelopes on the basis of their life-cycle analysis. In order to facilitate this analysis, a small-scale office building, the University Services Building (USB), with a built-up area of 148,101 ft2 situated on ASU campus in Tempe, Arizona was studied. The building's exterior envelope is the highlight of this study. The current exterior envelope is made of tilt-up concrete construction, a type of construction in which the concrete elements are constructed horizontally and tilted up, after they are cured, using cranes and are braced until other structural elements are secured. This building envelope is compared to five other building envelope systems (i.e. concrete block, insulated concrete form, cast-in-place concrete, steel studs and curtain wall constructions) evaluating them on the basis of least environmental impact. The research methodology involved developing energy models, simulating them and generating changes in energy consumption due to the above mentioned envelope types. Energy consumption data, along with various other details, such as building floor area, areas of walls, columns, beams etc. and their material types were imported into Life-Cycle Assessment software called ATHENA impact estimator for buildings. Using this four-stepped LCA methodology, the results showed that the Steel Stud envelope performed the best and less environmental impact compared to other envelope types. This research methodology can be applied to other building typologies.

  17. 46 CFR 163.003-11 - Materials.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL CONSTRUCTION Pilot Ladder § 163.003-11 Materials. (a) Suspension members. Each... defects affecting its strength or durability. (c) Wood preservative. After each wooden part is formed and...

  18. Problems Involved in the Choice and Use of Materials in Airplane Construction

    NASA Technical Reports Server (NTRS)

    Brenner, Paul

    1932-01-01

    The present state of the problem of materials in airplane construction is studied on the basis of data giving the principal characteristics of different materials and showing how they affect the form of airplane parts.

  19. Materials in use in U.S. interstate highways

    DOT National Transportation Integrated Search

    2006-10-01

    Natural aggregates (construction sand and gravel and crushed stone) make up the largest component of nonfuel mineral materials consumed in the United States. Most of these materials are used in construction activities, such as in buildings and roads....

  20. Evaluation of Minimum Asphalt Concrete Thickness Criteria

    DTIC Science & Technology

    2008-10-01

    9 Figure 6. Dry density versus moisture content for CH material... density measurements. ............................ 24 Figure 18. EPC installation in a crushed gravel base course layer...Construction Materials Materials Characterization Laboratory Testing Field Testing Test Section Construction Hydrometer, Modified Proctor , Specific

  1. Application of BIM technology in green building material management system

    NASA Astrophysics Data System (ADS)

    Zhineng, Tong

    2018-06-01

    The current green building materials management system in China's construction industry is not perfect, and there are still many shortcomings. Active construction of green building materials management system based on BIM technology, combined with the characteristics of green building materials and its relationship with BIM technology application, is urgently needed to better realize the scientific management of green building materials.

  2. Calibration of material models for estimating impact of construction quality on life cycle performance of pavements.

    DOT National Transportation Integrated Search

    2006-02-01

    Constructing a pavement that will perform well throughout its expected design life is the main goal of any highway agency. The relationship between construction parameters and pavement life, defined by structural models, can be described using materi...

  3. Architectural: Construction, Supervision, and Inspection. Course of Study.

    ERIC Educational Resources Information Center

    Robson, Frank

    This architectural course of study is part of a construction, supervision, and inspection series, which provides instructional materials for community or junior college technical courses in the inspection program. Material covered pertains to: construction contracts, schedules, and site preparation; footings and foundations; masonry and…

  4. 46 CFR 160.053-3 - Materials, construction and workmanship.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Work Vests, Unicellular Plastic... workmanship of unicellular plastic foam work vests specified by this subpart shall conform to the requirements.... All components used in the construction of work vests must meet the applicable requirements of subpart...

  5. 46 CFR 160.053-3 - Materials, construction and workmanship.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Work Vests, Unicellular Plastic... workmanship of unicellular plastic foam work vests specified by this subpart shall conform to the requirements.... All components used in the construction of work vests must meet the applicable requirements of subpart...

  6. 46 CFR 160.053-3 - Materials, construction and workmanship.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Work Vests, Unicellular Plastic... workmanship of unicellular plastic foam work vests specified by this subpart shall conform to the requirements.... All components used in the construction of work vests must meet the applicable requirements of subpart...

  7. Life cycle performances of log wood applied for soil bioengineering constructions

    NASA Astrophysics Data System (ADS)

    Kalny, Gerda; Strauss-Sieberth, Alexandra; Strauss, Alfred; Rauch, Hans Peter

    2016-04-01

    Nowadays there is a high demand on engineering solutions considering not only technical aspects but also ecological and aesthetic values. Soil bioengineering is a construction technique that uses biological components for hydraulic and civil engineering solutions. Soil bioengineering solutions are based on the application of living plants and other auxiliary materials including among others log wood. This kind of construction material supports the soil bioengineering system as long as the plants as living construction material overtake the stability function. Therefore it is important to know about the durability and the degradation process of the wooden logs to retain the integral performance of a soil bio engineering system. These aspects will be considered within the framework of the interdisciplinary research project „ELWIRA Plants, wood, steel and concrete - life cycle performances as construction materials". Therefore field investigations on soil bioengineering construction material, specifically European Larch wood logs, of different soil bioengineering structures at the river Wien have been conducted. The drilling resistance as a parameter for particular material characteristics of selected logs was measured and analysed. The drilling resistance was measured with a Rinntech Resistograph instrument at different positions of the wooden logs, all surrounded with three different backfills: Fully surrounded with air, with earth contact on one side and near the water surface in wet-dry conditions. The age of the used logs ranges from one year old up to 20 year old. Results show progress of the drilling resistance throughout the whole cross section as an indicator to assess soil bioengineering construction material. Logs surrounded by air showed a higher drilling resistance than logs with earth contact and the ones exposed to wet-dry conditions. Hence the functional capability of wooden logs were analysed and discussed in terms of different levels of degradation. The results contribute to a sustainable and resource conserving handling with building materials in frame of construction and maintenance works of soil bioengineering structures.

  8. Design, synthesis and applications of core-shell, hollow core, and nanorattle multifunctional nanostructures.

    PubMed

    El-Toni, Ahmed Mohamed; Habila, Mohamed A; Labis, Joselito Puzon; ALOthman, Zeid A; Alhoshan, Mansour; Elzatahry, Ahmed A; Zhang, Fan

    2016-02-07

    With the evolution of nanoscience and nanotechnology, studies have been focused on manipulating nanoparticle properties through the control of their size, composition, and morphology. As nanomaterial research has progressed, the foremost focus has gradually shifted from synthesis, morphology control, and characterization of properties to the investigation of function and the utility of integrating these materials and chemical sciences with the physical, biological, and medical fields, which therefore necessitates the development of novel materials that are capable of performing multiple tasks and functions. The construction of multifunctional nanomaterials that integrate two or more functions into a single geometry has been achieved through the surface-coating technique, which created a new class of substances designated as core-shell nanoparticles. Core-shell materials have growing and expanding applications due to the multifunctionality that is achieved through the formation of multiple shells as well as the manipulation of core/shell materials. Moreover, core removal from core-shell-based structures offers excellent opportunities to construct multifunctional hollow core architectures that possess huge storage capacities, low densities, and tunable optical properties. Furthermore, the fabrication of nanomaterials that have the combined properties of a core-shell structure with that of a hollow one has resulted in the creation of a new and important class of substances, known as the rattle core-shell nanoparticles, or nanorattles. The design strategies of these new multifunctional nanostructures (core-shell, hollow core, and nanorattle) are discussed in the first part of this review. In the second part, different synthesis and fabrication approaches for multifunctional core-shell, hollow core-shell and rattle core-shell architectures are highlighted. Finally, in the last part of the article, the versatile and diverse applications of these nanoarchitectures in catalysis, energy storage, sensing, and biomedicine are presented.

  9. Virtual Manufacturing Techniques Designed and Applied to Manufacturing Activities in the Manufacturing Integration and Technology Branch

    NASA Technical Reports Server (NTRS)

    Shearrow, Charles A.

    1999-01-01

    One of the identified goals of EM3 is to implement virtual manufacturing by the time the year 2000 has ended. To realize this goal of a true virtual manufacturing enterprise the initial development of a machinability database and the infrastructure must be completed. This will consist of the containment of the existing EM-NET problems and developing machine, tooling, and common materials databases. To integrate the virtual manufacturing enterprise with normal day to day operations the development of a parallel virtual manufacturing machinability database, virtual manufacturing database, virtual manufacturing paradigm, implementation/integration procedure, and testable verification models must be constructed. Common and virtual machinability databases will include the four distinct areas of machine tools, available tooling, common machine tool loads, and a materials database. The machine tools database will include the machine envelope, special machine attachments, tooling capacity, location within NASA-JSC or with a contractor, and availability/scheduling. The tooling database will include available standard tooling, custom in-house tooling, tool properties, and availability. The common materials database will include materials thickness ranges, strengths, types, and their availability. The virtual manufacturing databases will consist of virtual machines and virtual tooling directly related to the common and machinability databases. The items to be completed are the design and construction of the machinability databases, virtual manufacturing paradigm for NASA-JSC, implementation timeline, VNC model of one bridge mill and troubleshoot existing software and hardware problems with EN4NET. The final step of this virtual manufacturing project will be to integrate other production sites into the databases bringing JSC's EM3 into a position of becoming a clearing house for NASA's digital manufacturing needs creating a true virtual manufacturing enterprise.

  10. Life cycle assessment of construction and demolition waste management

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Butera, Stefania, E-mail: stbu@teknologisk.dk; Christensen, Thomas H.; Astrup, Thomas F.

    Highlights: • LCA of C&DW utilisation in road vs. C&DW landfilling. • C&DW utilisation in road better than landfilling for most categories. • Transportation is the most important process in non-toxic impact categories. • Leaching of oxyanions is the critical process in toxic impact categories. • Modelling of Cr fate in the subsoil is highly influential to the results. - Abstract: Life cycle assessment (LCA) modelling of construction and demolition waste (C&DW) management was carried out. The functional unit was management of 1 Mg mineral, source separated C&DW, which is either utilised in road construction as a substitute for naturalmore » aggregates, or landfilled. The assessed environmental impacts included both non-toxic and toxic impact categories. The scenarios comprised all stages of the end-of-life management of C&DW, until final disposal of all residues. Leaching of inorganic contaminants was included, as was the production of natural aggregates, which was avoided because of the use of C&DW. Typical uncertainties related to contaminant leaching were addressed. For most impact categories, utilisation of C&DW in road construction was preferable to landfilling; however, for most categories, utilisation resulted in net environmental burdens. Transportation represented the most important contribution for most nontoxic impacts, accounting for 60–95 per cent of these impacts. Capital goods contributed with negligible impacts. Leaching played a critical role for the toxic categories, where landfilling had lower impacts than utilisation because of the lower levels of leachate per ton of C&DW reaching the groundwater over a 100-year perspective. Leaching of oxyanions (As, V and Sb) was critical with respect to leaching. Typical experimental uncertainties in leaching data did not have a pivotal influence on the results; however, accounting for Cr immobilisation in soils as part of the impact assessment was critical for modelling the leaching impacts. Compared with the overall life cycle of building and construction materials, leaching emissions were shown to be potentially significant for toxicity impacts, compared with contributions from production of the same materials, showing that end-of-life impacts and leaching should not be disregarded when assessing environmental impacts from construction products and materials. CO{sub 2} uptake in the C&DW corresponding to 15 per cent carbonation could out-balance global warming impacts from transportation; however, carbonation would also likely result in increased toxicity impacts due to higher leaching of oxyanions.« less

  11. 48 CFR 546.312 - Construction contracts.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 4 2014-10-01 2014-10-01 false Construction contracts... CONTRACT MANAGEMENT QUALITY ASSURANCE Contract Clauses 546.312 Construction contracts. Insert the clause at 552.246-72, Final Inspection and Tests, in solicitations and contracts for construction that include...

  12. 48 CFR 546.312 - Construction contracts.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 4 2013-10-01 2013-10-01 false Construction contracts... CONTRACT MANAGEMENT QUALITY ASSURANCE Contract Clauses 546.312 Construction contracts. Insert the clause at 552.246-72, Final Inspection and Tests, in solicitations and contracts for construction that include...

  13. 48 CFR 546.312 - Construction contracts.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 4 2011-10-01 2011-10-01 false Construction contracts... CONTRACT MANAGEMENT QUALITY ASSURANCE Contract Clauses 546.312 Construction contracts. Insert the clause at 552.246-72, Final Inspection and Tests, in solicitations and contracts for construction that include...

  14. 48 CFR 546.312 - Construction contracts.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 4 2012-10-01 2012-10-01 false Construction contracts... CONTRACT MANAGEMENT QUALITY ASSURANCE Contract Clauses 546.312 Construction contracts. Insert the clause at 552.246-72, Final Inspection and Tests, in solicitations and contracts for construction that include...

  15. Investigation and demonstration of turbidity reduction in stormwater runoff for Oklahoma highway construction sites : final report.

    DOT National Transportation Integrated Search

    2013-12-01

    The Environmental protection Agency (USEPA) has issued new requirements on the construction industry to control the discharge of pollutants from the sites. The construction effluent guidelines or ELGs require construction sites to reduce the pollu...

  16. Nondestructive mechanical characterization of developing biological tissues using inflation testing.

    PubMed

    Oomen, P J A; van Kelle, M A J; Oomens, C W J; Bouten, C V C; Loerakker, S

    2017-10-01

    One of the hallmarks of biological soft tissues is their capacity to grow and remodel in response to changes in their environment. Although it is well-accepted that these processes occur at least partly to maintain a mechanical homeostasis, it remains unclear which mechanical constituent(s) determine(s) mechanical homeostasis. In the current study a nondestructive mechanical test and a two-step inverse analysis method were developed and validated to nondestructively estimate the mechanical properties of biological tissue during tissue culture. Nondestructive mechanical testing was achieved by performing an inflation test on tissues that were cultured inside a bioreactor, while the tissue displacement and thickness were nondestructively measured using ultrasound. The material parameters were estimated by an inverse finite element scheme, which was preceded by an analytical estimation step to rapidly obtain an initial estimate that already approximated the final solution. The efficiency and accuracy of the two-step inverse method was demonstrated on virtual experiments of several material types with known parameters. PDMS samples were used to demonstrate the method's feasibility, where it was shown that the proposed method yielded similar results to tensile testing. Finally, the method was applied to estimate the material properties of tissue-engineered constructs. Via this method, the evolution of mechanical properties during tissue growth and remodeling can now be monitored in a well-controlled system. The outcomes can be used to determine various mechanical constituents and to assess their contribution to mechanical homeostasis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Fast mix table construction for material discretization

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Johnson, S. R.

    2013-07-01

    An effective hybrid Monte Carlo-deterministic implementation typically requires the approximation of a continuous geometry description with a discretized piecewise-constant material field. The inherent geometry discretization error can be reduced somewhat by using material mixing, where multiple materials inside a discrete mesh voxel are homogenized. Material mixing requires the construction of a 'mix table,' which stores the volume fractions in every mixture so that multiple voxels with similar compositions can reference the same mixture. Mix table construction is a potentially expensive serial operation for large problems with many materials and voxels. We formulate an efficient algorithm to construct a sparse mixmore » table in O(number of voxels x log number of mixtures) time. The new algorithm is implemented in ADVANTG and used to discretize continuous geometries onto a structured Cartesian grid. When applied to an end-of-life MCNP model of the High Flux Isotope Reactor with 270 distinct materials, the new method improves the material mixing time by a factor of 100 compared to a naive mix table implementation. (authors)« less

  18. Fast Mix Table Construction for Material Discretization

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Johnson, Seth R

    2013-01-01

    An effective hybrid Monte Carlo--deterministic implementation typically requires the approximation of a continuous geometry description with a discretized piecewise-constant material field. The inherent geometry discretization error can be reduced somewhat by using material mixing, where multiple materials inside a discrete mesh voxel are homogenized. Material mixing requires the construction of a ``mix table,'' which stores the volume fractions in every mixture so that multiple voxels with similar compositions can reference the same mixture. Mix table construction is a potentially expensive serial operation for large problems with many materials and voxels. We formulate an efficient algorithm to construct a sparse mix table inmore » $$O(\\text{number of voxels}\\times \\log \\text{number of mixtures})$$ time. The new algorithm is implemented in ADVANTG and used to discretize continuous geometries onto a structured Cartesian grid. When applied to an end-of-life MCNP model of the High Flux Isotope Reactor with 270 distinct materials, the new method improves the material mixing time by a factor of 100 compared to a naive mix table implementation.« less

  19. High-rise construction in the Russian economy: modeling of management decisions

    NASA Astrophysics Data System (ADS)

    Miroshnikova, Tatyana; Taskaeva, Natalia

    2018-03-01

    The growth in the building industry, particularly in residential high-rise construction, is having considerable influence on the country's economic development. The scientific hypothesis of the research is that the execution of town-planning programs of high-rise construction depends to a large extent on the management of the provision of material resources for the construction of a millionth city, while the balance model is the most important tool for establishing and determining the ratio between supply and demand for material resources. In order to improve the efficiency of high-rise building management, it is proposed to develop a methodology for managing the provision of construction of large cities with material resources.

  20. Metal Construction

    NASA Technical Reports Server (NTRS)

    Verduzio, Rodolfo

    1922-01-01

    The future development of aerial navigation is closely connected with the condition of obtaining airplanes of great stability and sufficient strength. Different construction materials such as wood, aluminum, iron, and alloys are examined to determine which materials or combination of materials provides a greater coefficient of safety.

  1. Design Optimization of Hybrid FRP/RC Bridge

    NASA Astrophysics Data System (ADS)

    Papapetrou, Vasileios S.; Tamijani, Ali Y.; Brown, Jeff; Kim, Daewon

    2018-04-01

    The hybrid bridge consists of a Reinforced Concrete (RC) slab supported by U-shaped Fiber Reinforced Polymer (FRP) girders. Previous studies on similar hybrid bridges constructed in the United States and Europe seem to substantiate these hybrid designs for lightweight, high strength, and durable highway bridge construction. In the current study, computational and optimization analyses were carried out to investigate six composite material systems consisting of E-glass and carbon fibers. Optimization constraints are determined by stress, deflection and manufacturing requirements. Finite Element Analysis (FEA) and optimization software were utilized, and a framework was developed to run the complete analyses in an automated fashion. Prior to that, FEA validation of previous studies on similar U-shaped FRP girders that were constructed in Poland and Texas is presented. A finer optimization analysis is performed for the case of the Texas hybrid bridge. The optimization outcome of the hybrid FRP/RC bridge shows the appropriate composite material selection and cross-section geometry that satisfies all the applicable Limit States (LS) and, at the same time, results in the lightest design. Critical limit states show that shear stress criteria determine the optimum design for bridge spans less than 15.24 m and deflection criteria controls for longer spans. Increased side wall thickness can reduce maximum observed shear stresses, but leads to a high weight penalty. A taller cross-section and a thicker girder base can efficiently lower the observed deflections and normal stresses. Finally, substantial weight savings can be achieved by the optimization framework if base and side-wall thickness are treated as independent variables.

  2. Materials science and architecture

    NASA Astrophysics Data System (ADS)

    Bechthold, Martin; Weaver, James C.

    2017-12-01

    Materiality — the use of various materials in architecture — has been fundamental to the design and construction of buildings, and materials science has traditionally responded to needs formulated by design, engineering and construction professionals. Material properties and processes are shaping buildings and influencing how they perform. The advent of technologies such as digital fabrication, robotics and 3D printing have not only accelerated the development of new construction solutions, but have also led to a renewed interest in materials as a catalyst for novel architectural design. In parallel, materials science has transformed from a field that explains materials to one that designs materials from the bottom up. The conflation of these two trends is giving rise to materials-based design research in which architects, engineers and materials scientists work as partners in the conception of new materials systems and their applications. This Review surveys this development for different material classes (wood, ceramics, metals, concrete, glass, synthetic composites and polymers), with an emphasis on recent trends and innovations.

  3. Improvement of the material and transport component of the system of construction waste management

    NASA Astrophysics Data System (ADS)

    Kostyshak, Mikhail; Lunyakov, Mikhail

    2017-10-01

    Relevance of the topic of selected research is conditioned with the growth of construction operations and growth rates of construction and demolition wastes. This article considers modern approaches to the management of turnover of construction waste, sequence of reconstruction or demolition processes of the building, information flow of the complete cycle of turnover of construction and demolition waste, methods for improvement of the material and transport component of the construction waste management system. Performed analysis showed that mechanism of management of construction waste allows to increase efficiency and environmental safety of this branch and regions.

  4. Construction Exploration. Practical Arts. Instructor's Manual. Competency-Based Education.

    ERIC Educational Resources Information Center

    Keeton, Martha; And Others

    This manual provides curriculum materials for implementing a career exploration class in construction occupations within a Practical Arts Education program for middle/junior high school students. Introductory materials include the program master sequence, a list of construction occupations, and an overview of the competency-based instructional…

  5. 42 CFR 137.332 - On what basis may the Secretary reject a final construction project proposal?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... face clearly demonstrates that the construction project cannot be completed as proposed. (b) For construction programs proposed to be included in a construction project agreement, the Secretary may also... construction project proposal? 137.332 Section 137.332 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF...

  6. 40. From Final Construction Report on the Haleakala Road ProjectNR7, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    40. From Final Construction Report on the Haleakala Road Project--NR-7, Hawaii National Park, Island of Maui, Territory of Hawaii, T.H. GENERAL VIEW OT THE PROJECT SHOWING CONSPICUOUS SCARS. THE BEFORE PHOTO OF A BEFORE AND AFTER SET. AFTER PHOTO IS HI-52-41. - Haleakala National Park Roads, Pukalani, Maui County, HI

  7. 42 CFR 137.333 - What procedures must the Secretary follow if the Secretary rejects a final construction project...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false What procedures must the Secretary follow if the... What procedures must the Secretary follow if the Secretary rejects a final construction project... controlling legal authority supporting the rejection; (b) Within 20 days, provide all documents relied on in...

  8. 25 CFR 256.20 - How are these repairs or construction trades persons, home building contractors, or construction...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... statement of work, which identifies the work to be performed. The appropriate contracting office uses the... completing the project as advertised. (a) Payments to the winning bidder are negotiated in the contract and... the completed work. (2) Final payment will be made after final inspection and after all provisions of...

  9. Development of construction materials like concrete from lunar soils without water

    NASA Technical Reports Server (NTRS)

    Desai, Chandra S.; Saadatmanesh, H.; Frantziskonis, G.

    1989-01-01

    The development of construction materials such as concrete from lunar soils without the use of water requires a different methodology than that used for conventional terrestrial concrete. A unique approach is attempted that utilizes factors such as initial vacuum and then cyclic loading to enhance the mechanical properties of dry materials similar to those available on the moon. The application of such factors is expected to allow reorientation, and coming together, of particles of the materials toward the maximum theoretical density. If such a density can provide deformation and strength properties for even a limited type of construction, the approach can have significant application potential, although other factors such as heat and chemicals may be needed for specific construction objectives.

  10. Radiotherapy and Nuclear Medicine Project for an Integral Oncology Center at the Oaxaca High Specialization Regional Hospital

    NASA Astrophysics Data System (ADS)

    De Jesús, M.; Trujillo-Zamudio, F. E.

    2010-12-01

    A building project of Radiotherapy & Nuclear Medicine services (diagnostic and therapy), within an Integral Oncology Center (IOC), requires interdisciplinary participation of architects, biomedical engineers, radiation oncologists and medical physicists. This report focus on the medical physicist role in designing, building and commissioning stages, for the final clinical use of an IOC at the Oaxaca High Specialization Regional Hospital (HRAEO). As a first step, during design stage, the medical physicist participates in discussions about radiation safety and regulatory requirements for the National Regulatory Agency (called CNSNS in Mexico). Medical physicists propose solutions to clinical needs and take decisions about installing medical equipment, in order to fulfill technical and medical requirements. As a second step, during the construction stage, medical physicists keep an eye on building materials and structural specifications. Meanwhile, regulatory documentation must be sent to CNSNS. This documentation compiles information about medical equipment, radioactivity facility, radiation workers and nuclear material data, in order to obtain the license for the linear accelerator, brachytherapy and nuclear medicine facilities. As a final step, after equipment installation, the commissioning stage takes place. As the conclusion, we show that medical physicists are essentials in order to fulfill with Mexican regulatory requirements in medical facilities.

  11. 3D printing X-Ray Quality Control Phantoms. A Low Contrast Paradigm

    NASA Astrophysics Data System (ADS)

    Kapetanakis, I.; Fountos, G.; Michail, C.; Valais, I.; Kalyvas, N.

    2017-11-01

    Current 3D printing technology products may be usable in various biomedical applications. Such an application is the creation of X-ray quality control phantoms. In this work a self-assembled 3D printer (geeetech i3) was used for the design of a simple low contrast phantom. The printing material was Polylactic Acid (PLA) (100% printing density). Low contrast scheme was achieved by creating air-holes with different diameters and thicknesses, ranging from 1mm to 9mm. The phantom was irradiated at a Philips Diagnost 93 fluoroscopic installation at 40kV-70kV with the semi-automatic mode. The images were recorded with an Agfa cr30-x CR system and assessed with ImageJ software. The best contrast value observed was approximately 33%. In low contrast detectability check it was found that the 1mm diameter hole was always visible, for thickness larger or equal to 4mm. A reason for not being able to distinguish 1mm in smaller thicknesses might be the presence of printing patterns on the final image, which increased the structure noise. In conclusion the construction of a contrast resolution phantom with a 3D printer is feasible. The quality of the final product depends upon the printer accuracy and the material characteristics.

  12. Construction materials as a waste management solution for cellulose sludge

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Modolo, R., E-mail: regina.modolo@ua.pt; Ferreira, V.M.; Machado, L.M.

    2011-02-15

    Sustainable waste management system for effluents treatment sludge has been a pressing issue for pulp and paper sector. Recycling is always recommended in terms of environmental sustainability. Following an approach of waste valorisation, this work aims to demonstrate the technical viability of producing fiber-cement roof sheets incorporating cellulose primary sludge generated on paper and pulp mills. From the results obtained with preliminary studies it was possible to verify the possibility of producing fiber-cement sheets by replacing 25% of the conventional used virgin long fiber by primary effluent treatment cellulose sludge. This amount of incorporation was tested on an industrial scale.more » Environmental parameters related to water and waste, as well as tests for checking the quality of the final product was performed. These control parameters involved total solids in suspension, dissolved salts, chlorides, sulphates, COD, metals content. In the product, parameters like moisture, density and strength were controlled. The results showed that it is possible to replace the virgin long fibers pulp by primary sludge without impacts in final product characteristics and on the environment. This work ensures the elimination of significant waste amounts, which are nowadays sent to landfill, as well as reduces costs associated with the standard raw materials use in the fiber-cement industrial sector.« less

  13. The Role of Problem Construction in Creative Production

    ERIC Educational Resources Information Center

    Reiter-Palmon, Roni

    2017-01-01

    This paper provides an overview of theory and research regarding problem construction and identification. Specifically, the paper reviews a theoretical model of processes associated with problem construction and empirical evidence in relation to the model. Finally, the paper reviews the literature on team problem construction.

  14. Millwright Instructional Materials.

    ERIC Educational Resources Information Center

    Hendrix, Laborn J.; Pierce, Greg

    This manual contains instructional materials for use in training millwrights working in industrial and commercial construction sites. Intended as an innovative complement to on-the-job training in construction, the material is written in terms of student performance using behavioral objectives and measured by criterion-referenced evaluation…

  15. Effects of Impression Material, Impression Tray Type, and Type of Partial Edentulism on the Fit of Cobalt-Chromium Partial Denture Frameworks on Initial Clinical Insertion: A Retrospective Clinical Evaluation.

    PubMed

    Baig, Mirza Rustum; Akbar, Jaber Hussain; Qudeimat, Muawia; Omar, Ridwaan

    2018-02-15

    To evaluate the effects of impression material, impression tray type, and type of partial edentulism (ie, Kennedy class) on the accuracy of fit of cobalt-chromium (Co-Cr) partial removable dental prostheses (PRDP) in terms of the number of fabricated frameworks required until the attainment of adequate fit. Electronic case documentations of 120 partially edentulous patients provided with Co-Cr PRDP treatment for one or both arches were examined. Statistical analyses of data were performed using analysis of variance and Tukey honest significant difference test to compare the relationships between the different factors and the number of frameworks that needed to be fabricated for each patient (α = .05). Statistical analysis of data derived from 143 records (69 maxillary and 74 mandibular) revealed no significant correlation between impression material, tray type, or Kennedy class and the number of construction attempts for the pooled or individual arch data (P ≥ .05). In PRDP treatment, alginate can be chosen as a first-choice material, and metal stock trays can be a preferred option for making final impressions to fabricate Co-Cr frameworks.

  16. Rehabilitation of adobe buildings. Understanding different materials from Portugal

    NASA Astrophysics Data System (ADS)

    Costa, Cristiana; Rocha, Fernando; Velosa, Ana

    2016-04-01

    Earth construction is the oldest building material known, with documented cases of the use of earth bricks since Mesopotamia around 10 000 BC (Heathcote, 1995). The earth construction exists throughout the majority of the world in different cultures, and for some countries, nowadays it continues to be the main process of construction (Vega et al, 2011). Around 30% of the world's population lives in buildings made of earth materials. Earthen construction is an environmentally friendly technique with a social and cultural contribution; this advantage is increased when this type of construction is applied in developing countries where the material costs counterbalance with labour costs, and where other materials and techniques cannot be available (Ciancio et al, 2013). Studies of materials characterization are required in order to understand the composition and specific properties of the earth buildings, their heterogeneity and their degradation mechanisms. Some adobes from different buildings, ages and regions of Portugal were collected in order to characterize them (mineralogically, chemically and physically). It was possible to understand the composition of these materials and their differences. Main minerals are quartz, feldspars, calcite and phyllosilicates (mica and kaolinite). The mechanical behaviour of these materials isn't the best, but it is possible to improve it with some simple and cheap natural additives (kaolinitic soils). The characterization of these materials allows us to understand the differences between the materials from the different regions (controlled by locally available raw materials). Understanding these materials, and their properties, it is possible to formulate new ones for repair, conservation and rehabilitation works. The adobe bricks are an alternative of kiln baked bricks which has several advantages and one of the most important is that these materials are recyclable. Adobes are an excellent option for building rehabilitation, if composition is optimised.

  17. Waste-efficient materials procurement for construction projects: A structural equation modelling of critical success factors.

    PubMed

    Ajayi, Saheed O; Oyedele, Lukumon O

    2018-05-01

    Albeit the understanding that construction waste is caused by activities ranging from all stages of project delivery process, research efforts have been concentrated on design and construction stages, while the possibility of reducing waste through materials procurement process is widely neglected. This study aims at exploring and confirming strategies for achieving waste-efficient materials procurement in construction activities. The study employs sequential exploratory mixed method approach as its methodological framework, using focus group discussion, statistical analysis and structural equation modelling. The study suggests that for materials procurement to enhance waste minimisation in construction projects, the procurement process would be characterised by four features. These include suppliers' commitment to low waste measures, low waste purchase management, effective materials delivery management and waste-efficient Bill of Quantity, all of which have significant impacts on waste minimisation. This implies that commitment of materials suppliers to such measures as take back scheme and flexibility in supplying small materials quantity, among others, are expected of materials procurement. While low waste purchase management stipulates the need for such measures as reduced packaging and consideration of pre-assembled/pre-cut materials, efficient delivery management entails effective delivery and storage system as well as adequate protection of materials during the delivery process, among others. Waste-efficient specification and bill of quantity, on the other hand, requires accurate materials take-off and ordering of materials based on accurately prepared design documents and bill of quantity. Findings of this study could assist in understanding a set of measures that should be taken during materials procurement process, thereby corroborating waste management practices at other stages of project delivery process. Copyright © 2018. Published by Elsevier Ltd.

  18. Modeling and validation of spectral BRDF on material surface of space target

    NASA Astrophysics Data System (ADS)

    Hou, Qingyu; Zhi, Xiyang; Zhang, Huili; Zhang, Wei

    2014-11-01

    The modeling and the validation methods of the spectral BRDF on the material surface of space target were presented. First, the microscopic characteristics of the space targets' material surface were analyzed based on fiber-optic spectrometer using to measure the direction reflectivity of the typical materials surface. To determine the material surface of space target is isotropic, atomic force microscopy was used to measure the material surface structure of space target and obtain Gaussian distribution model of microscopic surface element height. Then, the spectral BRDF model based on that the characteristics of the material surface were isotropic and the surface micro-facet with the Gaussian distribution which we obtained was constructed. The model characterizes smooth and rough surface well for describing the material surface of the space target appropriately. Finally, a spectral BRDF measurement platform in a laboratory was set up, which contains tungsten halogen lamp lighting system, fiber optic spectrometer detection system and measuring mechanical systems with controlling the entire experimental measurement and collecting measurement data by computers automatically. Yellow thermal control material and solar cell were measured with the spectral BRDF, which showed the relationship between the reflection angle and BRDF values at three wavelengths in 380nm, 550nm, 780nm, and the difference between theoretical model values and the measured data was evaluated by relative RMS error. Data analysis shows that the relative RMS error is less than 6%, which verified the correctness of the spectral BRDF model.

  19. An Unlikely Silk: The Composite Material of Green Lacewing Cocoons

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Weisman, Sarah; Trueman, Holly E.; Mudie, Stephen T.

    2009-01-15

    Spiders routinely produce multiple types of silk; however, common wisdom has held that insect species produce one type of silk each. This work reports that the green lacewing (Mallada signata, Neuroptera) produces two distinct classes of silk. We identified and sequenced the gene that encodes the major protein component of the larval lacewing cocoon silk and demonstrated that it is unrelated to the adult lacewing egg-stalk silk. The cocoon silk protein is 49 kDa in size and is alanine rich (>40%), and it contains an {alpha}-helical secondary structure. The final instar lacewing larvae spin protein fibers of {approx}2 {mu}m diametermore » to construct a loosely woven cocoon. In a second stage of cocoon construction, the insects lay down an inner wall of lipids that uses the fibers as a scaffold. We propose that the silk protein fibers provide the mechanical strength of the composite lacewing cocoon whereas the lipid layer provides a barrier to water loss during pupation.« less

  20. Effectiveness of low-cost electromagnetic shielding using nail-together galvanized steel: Test results. Final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Williams, P.F.; Kennedy, E.L.; McCormack, R.G.

    1992-09-01

    The sensitivity of modern electronic equipment has increased the need for costly electromagnetic shielding. To reduce this cost, the U.S. Army Construction Engineering Research Laboratories (USACERL) has developed a new concept for shielding design that uses 28-gauge galvanized steel and standard galvanized nails. In this study, an electromagnetically shielded structure using the concept was designed, built, and evaluated for shielding effectiveness. The galvanized material was mounted to the standard USACERL test aperture and nailed to the wooden module frame, and the shielding effectiveness of the new construction design was measured using radio frequency antennas and receivers. Evaluations showed that themore » nail-together structure proved adequate for many shielding applications. However, while the galvanized steel met most shielding application requirements, this process added multiple seams to the structure, which decreased shielding in many instances by as much as 40 dB. Electromagnetic shielding, Electromagnetic pulse C3I Facilities.« less

  1. Current strategies in multiphasic scaffold design for osteochondral tissue engineering: A review.

    PubMed

    Yousefi, Azizeh-Mitra; Hoque, Md Enamul; Prasad, Rangabhatala G S V; Uth, Nicholas

    2015-07-01

    The repair of osteochondral defects requires a tissue engineering approach that aims at mimicking the physiological properties and structure of two different tissues (cartilage and bone) using specifically designed scaffold-cell constructs. Biphasic and triphasic approaches utilize two or three different architectures, materials, or composites to produce a multilayered construct. This article gives an overview of some of the current strategies in multiphasic/gradient-based scaffold architectures and compositions for tissue engineering of osteochondral defects. In addition, the application of finite element analysis (FEA) in scaffold design and simulation of in vitro and in vivo cell growth outcomes has been briefly covered. FEA-based approaches can potentially be coupled with computer-assisted fabrication systems for controlled deposition and additive manufacturing of the simulated patterns. Finally, a summary of the existing challenges associated with the repair of osteochondral defects as well as some recommendations for future directions have been brought up in the concluding section of this article. © 2014 Wiley Periodicals, Inc.

  2. Materials Refining for Structural Elements From Lunar Resources

    NASA Astrophysics Data System (ADS)

    Landis, Geoffrey A.

    1998-01-01

    Use of in situ resources for construction on the Moon will require manufacturing structural materials out of lunar resources. Many materials that are currently used for aerospace and construction require materials that have low availability on the Moon. For example, graphite fiber, SiC fiber, and artificial fiber composites (such as Kevlar, Spectra, etc.) are used as advanced lightweight structural materials on Earth, but the low availability of C on the Moon makes these poor choices. Likewise the polymers used as the matrix for these composites, epoxy or polyester, also suffer from the low availability of C. Bulk paving and construction materials such as cement or concrete suffer from the low availability of water on the Moon, while asphalt, a common paving material on Earth, suffers from the low availability of C.

  3. Stigmergic construction and topochemical information shape ant nest architecture

    PubMed Central

    Khuong, Anaïs; Gautrais, Jacques; Perna, Andrea; Sbaï, Chaker; Combe, Maud; Kuntz, Pascale; Jost, Christian; Theraulaz, Guy

    2016-01-01

    The nests of social insects are not only impressive because of their sheer complexity but also because they are built from individuals whose work is not centrally coordinated. A key question is how groups of insects coordinate their building actions. Here, we use a combination of experimental and modeling approaches to investigate nest construction in the ant Lasius niger. We quantify the construction dynamics and the 3D structures built by ants. Then, we characterize individual behaviors and the interactions of ants with the structures they build. We show that two main interactions are involved in the coordination of building actions: (i) a stigmergic-based interaction that controls the amplification of depositions at some locations and is attributable to a pheromone added by ants to the building material; and (ii) a template-based interaction in which ants use their body size as a cue to control the height at which they start to build a roof from existing pillars. We then develop a 3D stochastic model based on these individual behaviors to analyze the effect of pheromone presence and strength on construction dynamics. We show that the model can quantitatively reproduce key features of construction dynamics, including a large-scale pattern of regularly spaced pillars, the formation and merging of caps over the pillars, and the remodeling of built structures. Finally, our model suggests that the lifetime of the pheromone is a highly influential parameter that controls the growth and form of nest architecture. PMID:26787857

  4. Stigmergic construction and topochemical information shape ant nest architecture.

    PubMed

    Khuong, Anaïs; Gautrais, Jacques; Perna, Andrea; Sbaï, Chaker; Combe, Maud; Kuntz, Pascale; Jost, Christian; Theraulaz, Guy

    2016-02-02

    The nests of social insects are not only impressive because of their sheer complexity but also because they are built from individuals whose work is not centrally coordinated. A key question is how groups of insects coordinate their building actions. Here, we use a combination of experimental and modeling approaches to investigate nest construction in the ant Lasius niger. We quantify the construction dynamics and the 3D structures built by ants. Then, we characterize individual behaviors and the interactions of ants with the structures they build. We show that two main interactions are involved in the coordination of building actions: (i) a stigmergic-based interaction that controls the amplification of depositions at some locations and is attributable to a pheromone added by ants to the building material; and (ii) a template-based interaction in which ants use their body size as a cue to control the height at which they start to build a roof from existing pillars. We then develop a 3D stochastic model based on these individual behaviors to analyze the effect of pheromone presence and strength on construction dynamics. We show that the model can quantitatively reproduce key features of construction dynamics, including a large-scale pattern of regularly spaced pillars, the formation and merging of caps over the pillars, and the remodeling of built structures. Finally, our model suggests that the lifetime of the pheromone is a highly influential parameter that controls the growth and form of nest architecture.

  5. What Do Students "Construct" According to Constructivism in Science Education?

    NASA Astrophysics Data System (ADS)

    Bächtold, Manuel

    2013-12-01

    This paper aims at shedding light on what students can "construct" when they learn science and how this construction process may be supported. Constructivism is a pluralist theory of science education. As a consequence, I support, there are several points of view concerning this construction process. Firstly, I stress that constructivism is rooted in two fields, psychology of cognitive development and epistemology, which leads to two ways of describing the construction process: either as a process of enrichment and/or reorganization of the cognitive structures at the mental level, or as a process of building or development of models or theories at the symbolic level. Secondly, I argue that the usual distinction between "personal constructivism" (PC) and "social constructivism" (SC) originates in a difference of model of reference: the one of PC is Piaget's description of "spontaneous" concepts, assumed to be constructed by students on their own when interacting with their material environment, the one of SC is Vygotsky's description of scientific concepts, assumed to be introduced by the teacher by means of verbal communication. Thirdly, I support the idea that, within SC, there are in fact two trends: one, in line with Piaget's work, demonstrates how cooperation among students affects the development of each individual's cognitive structures; the other, in line with Vygotsky's work, claims that students can understand and master new models only if they are introduced to the scientific culture by their teacher. Fourthly, I draw attention to the process of "problem construction" identified by some French authors. Finally, I advocate for an integrated approach in science education, taking into account all the facets of science learning and teaching mentioned above and emphasizing their differences as well as their interrelations. Some suggestions intended to improve the efficiency of science teaching are made.

  6. Developmental Features of Children's Play with Objects.

    ERIC Educational Resources Information Center

    Vandenberg, Brian

    1981-01-01

    Examined whether the density of play continues to increase as children grow older. Four- and five-year-olds made simple constructions using few materials, six- and seven-year-olds made more constructions with more materials, and eight-to ten-year-olds made fewer but much more extensive and integrated constructions. (Author/DB)

  7. Preservation treatment for wood bridge application

    Treesearch

    Jake Bigelow; Stan Lebow; Carol A. Clausen; Lowell Greimann; Terry J. Wipf

    2009-01-01

    Timber can often be a cost-effective construction material for new bridges. The durability of the bridge greatly depends on proper attention to construction details and fabrication, as well as proper preservative treatment before, during, and after construction. Material repair and replacement costs for bridges are a considerable expense for highway agencies. To...

  8. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brogaard, L.K., E-mail: lksb@env.dtu.dk; Riber, C.; Christensen, T.H.

    Highlights: • Materials and energy used for the construction of waste incinerators were quantified. • The data was collected from five incineration plants in Scandinavia. • Included were six main materials, electronic systems, cables and all transportation. • The capital goods contributed 2–3% compared to the direct emissions impact on GW. - Abstract: Materials and energy used for the construction of modern waste incineration plants were quantified. The data was collected from five incineration plants (72,000–240,000 tonnes per year) built in Scandinavia (Norway, Finland and Denmark) between 2006 and 2012. Concrete for the buildings was the main material used amountingmore » to 19,000–26,000 tonnes per plant. The quantification further included six main materials, electronic systems, cables and all transportation. The energy used for the actual on-site construction of the incinerators was in the range 4000–5000 MW h. In terms of the environmental burden of producing the materials used in the construction, steel for the building and the machinery contributed the most. The material and energy used for the construction corresponded to the emission of 7–14 kg CO{sub 2} per tonne of waste combusted throughout the lifetime of the incineration plant. The assessment showed that, compared to data reported in the literature on direct emissions from the operation of incinerators, the environmental impacts caused by the construction of buildings and machinery (capital goods) could amount to 2–3% with respect to kg CO{sub 2} per tonne of waste combusted.« less

  9. Review on the Traditional Uses and Potential of Totora (Schoenoplectus Californicus) as Construction Material

    NASA Astrophysics Data System (ADS)

    Hidalgo-Cordero, Juan Fernando; García-Navarro, Justo

    2017-10-01

    The recent advances in the wood construction field have demonstrated the feasibility and advantages of using wood-based materials in tall buildings structures and other constructive uses, which could lead to a net reduction in CO2eq emissions of the construction sector by replacing high-energy consuming materials like concrete or steel, with wood and biomass-based materials. Among these biomass-based materials are the Non-Timber Forest Products (NTFP)which are plantsthat canprovide important contributionsto the construction sector and help to reduce the net CO2eq emissions of the building industry. One of these plants is the totora (Schoenoplectus Californicus) that has been long used by several communities for making handicrafts and as construction material. Recent studies on this plant have analyzed its properties and its feasibility to be used for producing materials of interest to the contemporary building industry. The totora is a bulrush that grows in lakes and marshes in America from California to Chile and some of the Pacific islands. It grows from the sea level to 4500maasl, it can grow in fresh water and estuaries, and it is resistant to water level changes and drought. This bulrush has been used by many cultures as medicine, food, forage, material for building houses, boats and different handicrafts. The most important examples of the use of totora in the world are the floating islands of the Uros in Lake Titicaca. The Uros people have developed traditional techniques for building their homes, boats, and even the artificial islands where they live on with methods based almost exclusively on the totora. This way of living and production system has been maintained for more than 500 years. This review is about the main constructive techniques that have been used for traditional construction in totora and some of therecent researches that have been made on this subject. Experiments in architecture and industrial design objects made with totora have shown its versatility, durability and high aesthetic value which is exploited in object design and architectural finishes. Additionally, recent studies on the insulating capacity of totora samples have determined an average conductivity of 0,06W/mK, which is comparable to some of the common insulating materials in the current market. The review of the historical uses and recent studies on this material indicate its potential in the contemporary construction field along with other environmental benefits. One of the key features is the totora productivity that can be as much as 56 tons of dry matter per hectare per year, which is near 5 times the average production of a conifer plantation. Therefore, to foster the research about its feasible applications in the contemporary construction field could lead to the reduction of the pressure on wood forests and plantations by developing a new material source for the construction industry.

  10. 34 CFR 75.605 - Beginning the construction.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... by a Grantee? Construction § 75.605 Beginning the construction. (a) A grantee shall begin work on... advertised or placed on the market for bidding, the grantee shall get approval by the Secretary of the final...

  11. Construction of a Novel Three-Dimensional PEDOT/RVC Electrode Structure for Capacitive Deionization: Testing and Performance

    PubMed Central

    Rahaman, Mostafizur; Govindasami, Periyasami; Almoiqli, Mohammed; Altalhi, Tariq; Mezni, Amine

    2017-01-01

    This article discusses the deposition of different amount of microstuctured poly(3,4-ethylenedioxythiophene) (PEDOT) on reticulated vitreous carbon (RVC) by electrochemical method to prepare three-dimensional (3D) PEDOT/RVC electrodes aimed to be used in capacitive deionization (CDI) technology. A CDI unit cell has been constructed here in this study. The performance of CDI cell in the ion removal of NaCl onto the sites of PEDOT/RVC electrode has been systematically investigated in terms of flow-rate, applied electrical voltage, and increasing PEDOT loading on PEDOT/RVC electrodes. It is observed that the increase in flow-rate, electric voltage, and PEDOT loading up to a certain level improve the ion removal performance of electrode in the CDI cell. The result shows that these electrodes can be used effectively for desalination technology, as the electrosorption capacity/desalination performance of these electrodes is quite high compared to carbon materials. Moreover, the stability of the electrodes has been tested and it is reported that these electrodes are regenerative. The effect of increasing NaCl concentration on the electrosorption capacity has also been investigated for these electrodes. Finally, it has been shown that 1 m3 PEDOT-120 min/RVC electrodes from 75 mg/L NaCl feed solution produce 421, 978 L water per day of 20 mg/L NaCl final concentration. PMID:28773205

  12. Construction of a Novel Three-Dimensional PEDOT/RVC Electrode Structure for Capacitive Deionization: Testing and Performance.

    PubMed

    Aldalbahi, Ali; Rahaman, Mostafizur; Govindasami, Periyasami; Almoiqli, Mohammed; Altalhi, Tariq; Mezni, Amine

    2017-07-24

    This article discusses the deposition of different amount of microstuctured poly(3,4-ethylenedioxythiophene) (PEDOT) on reticulated vitreous carbon (RVC) by electrochemical method to prepare three-dimensional (3D) PEDOT/RVC electrodes aimed to be used in capacitive deionization (CDI) technology. A CDI unit cell has been constructed here in this study. The performance of CDI cell in the ion removal of NaCl onto the sites of PEDOT/RVC electrode has been systematically investigated in terms of flow-rate, applied electrical voltage, and increasing PEDOT loading on PEDOT/RVC electrodes. It is observed that the increase in flow-rate, electric voltage, and PEDOT loading up to a certain level improve the ion removal performance of electrode in the CDI cell. The result shows that these electrodes can be used effectively for desalination technology, as the electrosorption capacity/desalination performance of these electrodes is quite high compared to carbon materials. Moreover, the stability of the electrodes has been tested and it is reported that these electrodes are regenerative. The effect of increasing NaCl concentration on the electrosorption capacity has also been investigated for these electrodes. Finally, it has been shown that 1 m³ PEDOT-120 min/RVC electrodes from 75 mg/L NaCl feed solution produce 421, 978 L water per day of 20 mg/L NaCl final concentration.

  13. 40 CFR 265.1100 - Applicability.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...: (1) A primary barrier designed and constructed of materials to prevent migration of hazardous... constructed of materials to prevent migration of hazardous constituents into the barrier, with a leak...

  14. 40 CFR 265.1100 - Applicability.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...: (1) A primary barrier designed and constructed of materials to prevent migration of hazardous... constructed of materials to prevent migration of hazardous constituents into the barrier, with a leak...

  15. 40 CFR 265.1100 - Applicability.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...: (1) A primary barrier designed and constructed of materials to prevent migration of hazardous... constructed of materials to prevent migration of hazardous constituents into the barrier, with a leak...

  16. 49 CFR 395.2 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... merchandising activities designed to retain the customer or to increase the sale of goods or services, in... construction materials and equipment means the transportation of construction and pavement materials...

  17. 40 CFR 265.1100 - Applicability.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...: (1) A primary barrier designed and constructed of materials to prevent migration of hazardous... constructed of materials to prevent migration of hazardous constituents into the barrier, with a leak...

  18. 40 CFR 265.1100 - Applicability.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...: (1) A primary barrier designed and constructed of materials to prevent migration of hazardous... constructed of materials to prevent migration of hazardous constituents into the barrier, with a leak...

  19. WET-WEATHER POLLUTION PREVENTION THROUGH MATERIALS SUBSTITUTION AS PART OF INDUSTRIAL CONSTRUCTION

    EPA Science Inventory

    A literature review of urban stormwater runoff and building/construction materials has shown that many materials such as galvanized metal, concrete, asphalt, and wood products, have the potential to release pollutants into urban stormwater runoff and snowmelt. However, much of th...

  20. Developing improved opportunities for the recycling and reuse of materials in road, bridge, and construction projects.

    DOT National Transportation Integrated Search

    2014-12-01

    The use of recycled and reused materials in transportation construction reduces consumption of non-renewable : resources. The objective of this research was to develop opportunities for improving the recycling and reuse of : materials in road and bri...

  1. Self-cleaning geopolymer concrete - A review

    NASA Astrophysics Data System (ADS)

    Norsaffirah Zailan, Siti; Mahmed, Norsuria; Bakri Abdullah, Mohd Mustafa Al; Sandu, Andrei Victor

    2016-06-01

    Concrete is the most widely used construction materials for building technology. However, cement production releases high amounts of carbon dioxide (CO2) to the atmosphere that leads to increasing the global warming. Thus, an alternative, environmental friendly construction material such as geopolymer concrete has been developed. Geopolymer concrete applies greener alternative binder, which is an innovative construction material that replaces the Portland cement. This technology introduced nano-particles such as nanoclay into the cement paste in order to improve their mechanical properties. The concrete materials also have been developed to be functioned as self-cleaning construction materials. The self-cleaning properties of the concrete are induced by introducing the photocatalytic materials such as titania (TiO2) and zinc oxide (ZnO). Self-cleaning concrete that contains those photocatalysts will be energized by ultraviolet (UV) radiation and accelerates the decomposition of organic particulates. Thus, the cleanliness of the building surfaces can be maintained and the air surrounding air pollution can be reduced. This paper briefly reviews about self-cleaning concrete.

  2. Radon and material radiopurity assessment for the NEXT double beta decay experiment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cebrián, S.; Dafni, T.; González-Díaz, D.

    The ”Neutrino Experiment with a Xenon TPC” (NEXT), intended to investigate the neutrinoless double beta decay using a high-pressure xenon gas TPC filled with Xe enriched in {sup 136}Xe at the Canfranc Underground Laboratory in Spain, requires ultra-low background conditions demanding an exhaustive control of material radiopurity and environmental radon levels. An extensive material screening process is underway for several years based mainly on gamma-ray spectroscopy using ultra-low background germanium detectors in Canfranc but also on mass spectrometry techniques like GDMS and ICPMS. Components from shielding, pressure vessel, electroluminescence and high voltage elements and energy and tracking readout planes havemore » been analyzed, helping in the final design of the experiment and in the construction of the background model. The latest measurements carried out will be presented and the implication on NEXT of their results will be discussed. The commissioning of the NEW detector, as a first step towards NEXT, has started in Canfranc; in-situ measurements of airborne radon levels were taken there to optimize the system for radon mitigation and will be shown too.« less

  3. Wave propagation in equivalent continuums representing truss lattice materials

    DOE PAGES

    Messner, Mark C.; Barham, Matthew I.; Kumar, Mukul; ...

    2015-07-29

    Stiffness scales linearly with density in stretch-dominated lattice meta-materials offering the possibility of very light yet very stiff structures. Current additive manufacturing techniques can assemble structures from lattice materials, but the design of such structures will require accurate, efficient simulation methods. Equivalent continuum models have several advantages over discrete truss models of stretch dominated lattices, including computational efficiency and ease of model construction. However, the development an equivalent model suitable for representing the dynamic response of a periodic truss in the small deformation regime is complicated by microinertial effects. This study derives a dynamic equivalent continuum model for periodic trussmore » structures suitable for representing long-wavelength wave propagation and verifies it against the full Bloch wave theory and detailed finite element simulations. The model must incorporate microinertial effects to accurately reproduce long wavelength characteristics of the response such as anisotropic elastic soundspeeds. Finally, the formulation presented here also improves upon previous work by preserving equilibrium at truss joints for simple lattices and by improving numerical stability by eliminating vertices in the effective yield surface.« less

  4. Monte Carlo simulations of safeguards neutron counter for oxide reduction process feed material

    NASA Astrophysics Data System (ADS)

    Seo, Hee; Lee, Chaehun; Oh, Jong-Myeong; An, Su Jung; Ahn, Seong-Kyu; Park, Se-Hwan; Ku, Jeong-Hoe

    2016-10-01

    One of the options for spent-fuel management in Korea is pyroprocessing whose main process flow is the head-end process followed by oxide reduction, electrorefining, and electrowining. In the present study, a well-type passive neutron coincidence counter, namely, the ACP (Advanced spent fuel Conditioning Process) safeguards neutron counter (ASNC), was redesigned for safeguards of a hot-cell facility related to the oxide reduction process. To this end, first, the isotopic composition, gamma/neutron emission yield and energy spectrum of the feed material ( i.e., the UO2 porous pellet) were calculated using the OrigenARP code. Then, the proper thickness of the gammaray shield was determined, both by irradiation testing at a standard dosimetry laboratory and by MCNP6 simulations using the parameters obtained from the OrigenARP calculation. Finally, the neutron coincidence counter's calibration curve for 100- to 1000-g porous pellets, in consideration of the process batch size, was determined through simulations. Based on these simulation results, the neutron counter currently is under construction. In the near future, it will be installed in a hot cell and tested with spent fuel materials.

  5. High velocity collisions of nanoparticles

    NASA Astrophysics Data System (ADS)

    Johnson, Donald F.; Mattson, William D.

    2017-01-01

    Nanoparticles (NPs) are a unique class of material with highly functionalizable surfaces and exciting applications. With a large surface-to-volume ratio and potentially high surface tension, shocked nanoparticles might display unique materials behavior. Using density functional theory, we have simulated high-velocity NP collisions under a variety of conditions. NPs composed of diamond-C, cubic-BN, and diamond-Si were considered with particle sizes up to 3.5 nm diameter. Additional simulations involved NPs that were destabilized by incorporating internal strain. The initial spherical NP structures were carved out of bulk crystals while the NPs with internal strain were constructed as a dense core (compressive strain) encompassed by a thin shell (tensile strain). Both on-axis and off-axis collisions were simulated at 10 km/s relative velocity. The amount of internal strain was artificially increased by creating a dense inner core with bond lengths compressed up to 8%. Collision dynamics, shock propagation, and fragmentation will be analyzed, but the simulation are ongoing and results are not finalized. The effect of material properties, internal strain, and collision velocity will be discussed.

  6. Application of advanced material systems to composite frame elements

    NASA Technical Reports Server (NTRS)

    Llorente, Steven; Minguet, Pierre; Fay, Russell; Medwin, Steven

    1992-01-01

    A three phase program has been conducted to investigate DuPont's Long Discontinuous Fiber (LDF) composites. Additional tests were conducted to compare LDF composites against toughened thermosets and a baseline thermoset system. Results have shown that the LDF AS4/PEKK offers improved interlaminar (flange bending) strength with little reduction in mechanical properties due to the discontinuous nature of the fibers. In the third phase, a series of AS4/PEKK LDF C-section curved frames (representing a typical rotorcraft light frame) were designed, manufactured and tested. Specimen reconsolidation after 'stretch forming' and frame thickness were found to be key factors in this light frame's performance. A finite element model was constructed to correlate frame test results with expected strain levels determined from material property tests. Adequately reconsolidated frames performed well and failed at strain levels at or above baseline thermoset material test strains. Finally a cost study was conducted which has shown that the use of LDF for this frame would result in a significant cost savings, for moderate to large lot sizes compared with the hand lay-up of a thermoset frame.

  7. Photoluminescent SBA-16 Rhombic Dodecahedral Particles: Assembly, Characterization, and ab Initio Modeling.

    PubMed

    Ruso, Juan M; Pardo, Victor; Sartuqui, Javier; Gravina, Noel; D'Elía, Noelia L; Pieroni, Olga I; Messina, Paula V

    2015-06-17

    Nowadays, the use of polyhedral instead of spherical particles as building blocks of engineering new materials has become an area of particular effort in the scientific community. Therefore, fabricating in a reproducible manner large amounts of uniform crystal-like particles is a huge challenge. In this work we report a low reagent-consuming binary surfactant templated method mediated by a hydrothermal treatment as a facile and controllable route for the synthesis of crystal-like rombdodecahedral particles exhibiting SBA-16 mesoporosity. It was determined that the hydrothermal treatment conditions were a key point upon the final material morphology, surface area, microporosity, wall thickness, and mesopore width. As a consequence of their internal mesoporosity order, rhombic dodecahedral synthesized particles exhibited highly efficient ultraviolet absorptions and photoluminescence emissions at room temperature. Conducting experimental and theoretical comparative studies allowed us to infer that the presence of intrinsic defects confined into an ordered mesoporous structure plays a very important role in semiconductor materials. The information presented here is expected to be useful, giving new, accurate information, for the construction of novel technological devices.

  8. 75 FR 68215 - Direct Final Rule Staying Numeric Limitation for the Construction and Development Point Source...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-05

    ... required to obtain NPDES permit coverage and performing the following activities: Construction of buildings, including building, developing and general contracting. Heavy and civil 237 engineering construction... Rule Staying Numeric Limitation for the Construction and Development Point Source Category AGENCY...

  9. Health Promotion at the Construction Work Site: The Lunch Truck Pilot Study.

    PubMed

    Caban-Martinez, Alberto J; Moore, Kevin J; Clarke, Tainya C; Davila, Evelyn P; Clark, John D; Lee, David J; Fleming, Lora E

    2018-04-01

    The transient nature of construction work makes it difficult to conduct longitudinal worksite-based health promotion activities. As part of a workplace health assessment pilot study, we worked with a commercial lunch truck company to disseminate four types of health education materials including cancer screening, workplace injury prevention, fruit and vegetable consumption, and smoking cessation to construction workers purchasing food items from the truck during their job breaks. Two weeks following the worksite assessment, we followed up with these workers to ascertain their use of the health promotion materials. Of the 54 workers surveyed, 83% reported reviewing and sharing the cancer screening materials with their families, whereas 44% discussed the cancer screening materials with coworkers. Similar proportions of workers reviewed, shared, and discussed the other health promotion materials with their family. Lunch trucks may be an effective strategy and delivery method for educating construction workers on healthy behaviors and injury prevention practices.

  10. French Modular Impoundment: Final Cost and Performance Evaluation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Drown, Peter; French, Bill

    This report comprises the Final Cost and Performance Report for the Department of Energy Award # EE0007244, the French Modular Impoundment (aka the “French Dam”.) The French Dam is a system of applying precast modular construction to water control structures. The “French Dam” is a term used to cover the construction means/methods used to construct or rehabilitate dams, diversion structures, powerhouses, and other hydraulic structures which impound water and are covered under FDE’s existing IP (Patents # US8414223B2; US9103084B2.)

  11. A MULTISCALE FRAMEWORK FOR THE STOCHASTIC ASSIMILATION AND MODELING OF UNCERTAINTY ASSOCIATED NCF COMPOSITE MATERIALS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mehrez, Loujaine; Ghanem, Roger; McAuliffe, Colin

    multiscale framework to construct stochastic macroscopic constitutive material models is proposed. A spectral projection approach, specifically polynomial chaos expansion, has been used to construct explicit functional relationships between the homogenized properties and input parameters from finer scales. A homogenization engine embedded in Multiscale Designer, software for composite materials, has been used for the upscaling process. The framework is demonstrated using non-crimp fabric composite materials by constructing probabilistic models of the homogenized properties of a non-crimp fabric laminate in terms of the input parameters together with the homogenized properties from finer scales.

  12. Selective classification and quantification model of C&D waste from material resources consumed in residential building construction.

    PubMed

    Mercader-Moyano, Pilar; Ramírez-de-Arellano-Agudo, Antonio

    2013-05-01

    The unfortunate economic situation involving Spain and the European Union is, among other factors, the result of intensive construction activity over recent years. The excessive consumption of natural resources, together with the impact caused by the uncontrolled dumping of untreated C&D waste in illegal landfills have caused environmental pollution and a deterioration of the landscape. The objective of this research was to generate a selective classification and quantification model of C&D waste based on the material resources consumed in the construction of residential buildings, either new or renovated, namely the Conventional Constructive Model (CCM). A practical example carried out on ten residential buildings in Seville, Spain, enabled the identification and quantification of the C&D waste generated in their construction and the origin of the waste, in terms of the building material from which it originated and its impact for every m(2) constructed. This model enables other researchers to establish comparisons between the various improvements proposed for the minimization of the environmental impact produced by building a CCM, new corrective measures to be proposed in future policies that regulate the production and management of C&D waste generated in construction from the design stage to the completion of the construction process, and the establishment of sustainable management for C&D waste and for the selection of materials for the construction on projected or renovated buildings.

  13. Craft Stick Beams

    NASA Technical Reports Server (NTRS)

    Karplus, Alan K.

    1996-01-01

    The objective of this exercise is to provide a phenomenological 'hands-on' experience that shows how geometry can affect the load carrying capacity of a material used in construction, how different materials have different failure characteristics, and how construction affects the performance of a composite material. This will be accomplished by building beams of a single material and composite beams of a mixture of materials (popsicle sticks, fiberboard sheets, and tongue depressors); testing these layered beams to determine how and where they fail; and based on the failure analysis, designing a layered beam that will fail in a predicted manner. The students will learn the effects of lamination, adhesion, and geometry in layered beam construction on beam strength and failure location.

  14. Crushed cement concrete substitution for construction aggregates; a materials flow analysis

    USGS Publications Warehouse

    Kelly, Thomas

    1998-01-01

    An analysis of the substitution of crushed cement concrete for natural construction aggregates is performed by using a materials flow diagram that tracks all material flows into and out of the cement concrete portion of the products made with cement concrete: highways, roads, and buildings. Crushed cement concrete is only one of the materials flowing into these products, and the amount of crushed cement concrete substituted influences the amount of other materials in the flow. Factors such as availability and transportation costs, as well as physical properties, that can affect stability and finishability, influence whether crushed cement concrete or construction aggregates should be used or predominate for a particular end use.

  15. 46 CFR 160.047-3 - Materials.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS... and Child § 160.047-3 Materials. (a) General. All components used in the construction of buoyant vests... loops for an adult or child size buoyant vest specified by this subpart must be 3/4-inch cotton webbing...

  16. Electronic construction collaboration system -- final phase : [tech transfer summary].

    DOT National Transportation Integrated Search

    2014-07-01

    Construction projects have been growing more complex in terms of : project team composition, design aspects, and construction processes. : To help manage the shop/working drawings and requests for information : (RFIs) for its large, complex projects,...

  17. Consent Agreement and Final Order Issued to Clark Construction Group, LLC

    EPA Pesticide Factsheets

    EPA Mid-Atlantic Region and Clark Construction Group, LLC has reached an agreement to settle Clean Water Act violations at The Wharf at Southwest Waterfront construction site in the amount of $19,000.

  18. Managing with A/E Ease

    DTIC Science & Technology

    1988-07-01

    16. Construction Fixes ($K). ([ a16(s) [ bl6 (s)] [ d16(s) 17. Final Actions on Pursuit Cases. ([ a17(s) ]) [bl7(s)] [ d17(s) 18. Carry Over to Next...Construction Fixes ($K). ( [al6 ]) [ b16 ] [d16 17. Final Actions on Pursuit Cases. ( [a17 ]) [b17 ] [d17 18. Carry Over to Next Quarter. [b18 ] [d18 .else

  19. 75 FR 46914 - Certain New Pneumatic Off-the-Road Tires From the People's Republic of China: Final Results of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-04

    ... sites. They can also be used to perform ``rough grading'' in road construction. \\17\\ A straddle carrier... commonly used in maintenance of unpaved roads and road construction to prepare the base course on to which...-the-Road Tires From the People's Republic of China: Final Results of Changed Circumstances Review...

  20. 34. From Final Construction Report on the Haleakala Road ProjectNR7, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    34. From Final Construction Report on the Haleakala Road Project--NR-7, Hawaii National Park, Island of Maui, Territory of Hawaii, H.L. Handley, Assistant Highway Engineer, March 30, 1935. NOTE HOW THE LOCATION FITS THE CONTOUR OF THE HILL. LOOKING FROM STATION 382+00 ON HALEAKALA HIGHWAY. - Haleakala National Park Roads, Pukalani, Maui County, HI

  1. 40 CFR 62.14535 - When must I comply with this subpart if I plan to continue operation of my CISWI unit?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Compliance Schedule...) You must submit a waste management plan no later than April 5, 2004. (3) You must achieve final... complete retrofit construction of control devices, as specified in the final control plan, so that, if the...

  2. Discrete elements for 3D microfluidics.

    PubMed

    Bhargava, Krisna C; Thompson, Bryant; Malmstadt, Noah

    2014-10-21

    Microfluidic systems are rapidly becoming commonplace tools for high-precision materials synthesis, biochemical sample preparation, and biophysical analysis. Typically, microfluidic systems are constructed in monolithic form by means of microfabrication and, increasingly, by additive techniques. These methods restrict the design and assembly of truly complex systems by placing unnecessary emphasis on complete functional integration of operational elements in a planar environment. Here, we present a solution based on discrete elements that liberates designers to build large-scale microfluidic systems in three dimensions that are modular, diverse, and predictable by simple network analysis techniques. We develop a sample library of standardized components and connectors manufactured using stereolithography. We predict and validate the flow characteristics of these individual components to design and construct a tunable concentration gradient generator with a scalable number of parallel outputs. We show that these systems are rapidly reconfigurable by constructing three variations of a device for generating monodisperse microdroplets in two distinct size regimes and in a high-throughput mode by simple replacement of emulsifier subcircuits. Finally, we demonstrate the capability for active process monitoring by constructing an optical sensing element for detecting water droplets in a fluorocarbon stream and quantifying their size and frequency. By moving away from large-scale integration toward standardized discrete elements, we demonstrate the potential to reduce the practice of designing and assembling complex 3D microfluidic circuits to a methodology comparable to that found in the electronics industry.

  3. Environmental risks of HBCDD from construction and demolition waste: a contemporary and future issue.

    PubMed

    Nie, Zhiqiang; Yang, Ziliang; Fang, Yanyan; Yang, Yufei; Tang, Zhenwu; Wang, Xingrun; Die, Qingqi; Gao, Xingbao; Zhang, Fengsong; Wang, Qi; Huang, Qifei

    2015-11-01

    Hexabromocyclododecane (HBCDD), as one of the most widely used brominated flame retardants (BFRs), is of great concern globally because of its persistence in the environment and negative impacts on humans and animals. HBCDD has been mainly used in flame-retarded expanded (EPS) and extruded (XPS) polystyrene foams for insulation in the construction industry. Most of these products will become a part of the construction and demolition (C&D) waste at the end of their life cycle (30-50 years) which is typically disposed of into landfills or incineration. However, the recycling of this material takes quite a low share compared with landfill and incineration. Consequently, high environmental risks will exist in these disposal approaches due to the HBCDD in C&D waste. Currently, XPS or EPS products containing HBCDD in the construction industry have not reached the end of their life cycle in most countries. Relatively little attention has been paid to this emergency issue by either the government or public. Furthermore, C&D waste is most likely disposed of by direct dumping, simple stacking, or open burning in developing countries. Therefore, this paper highlights the global environmental risks of HBCDD from C&D waste. Areas of research for key problems of HBCDD contained in C&D waste are suggested to help control and finally eliminate the impact.

  4. Waste glass as eco-friendly replacement material in construction products

    NASA Astrophysics Data System (ADS)

    Sharma, Gayatri; Sharma, Anu

    2018-05-01

    Atpresent time the biggest issue is increasing urban population, industrialization and development all over the world. The quantity of the raw materials of construction products like cement, concrete etc is gradually depleting. This is important because if we don't find the alternative material to accomplish need of this industry, with every year it will put pressure on natural resources which are limited in quantity. This major issue can be solved by partial replacing with waste glass of different construction products. This paper gives an overview of the current growth and recycling situation of waste glass and point out the direction for the proper use of waste glass as replacement of construction material. These will not only help in the reuse of waste glass but also create eco-friendly environment.

  5. 75 FR 59933 - Specifications and Drawings for Construction of Direct Buried Plant

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-29

    ... for Construction of Direct Buried Plant AGENCY: Rural Utilities Service, USDA. ACTION: Final rule..., Specifications and Drawings for Construction of Direct Buried Plant (Form 515a). The revised specifications will include new construction units for Fiber-to-the-Home, remove redundant or outdated requirements, and...

  6. Natural Resource Information System. Volume 1: Overall description

    NASA Technical Reports Server (NTRS)

    1972-01-01

    A prototype computer-based Natural Resource Information System was designed which could store, process, and display data of maximum usefulness to land management decision making. The system includes graphic input and display, the use of remote sensing as a data source, and it is useful at multiple management levels. A survey established current decision making processes and functions, information requirements, and data collection and processing procedures. The applications of remote sensing data and processing requirements were established. Processing software was constructed and a data base established using high-altitude imagery and map coverage of selected areas of SE Arizona. Finally a demonstration of system processing functions was conducted utilizing material from the data base.

  7. Dielectric elastomer actuators used for pneumatic valve technology

    NASA Astrophysics Data System (ADS)

    Giousouf, Metin; Kovacs, Gabor

    2013-10-01

    Dielectric elastomer actuators have been investigated for applications in the field of pneumatic automation technology. We have developed different valve designs with stacked dielectric elastomer actuators and with integrated high voltage converters. The actuators were made using VHB-4910 material and a stacker machine for automated fabrication of the cylindrical actuators. Typical characteristics of pneumatic valves such as flow rate, power consumption and dynamic behaviour are presented. For valve construction the force and stroke parameters of the dielectric elastomer actuator have been measured. Further, benefits for valve applications using dielectric elastomers are shown as well as their potential operational area. Finally, challenges are discussed that are relevant for the use of elastomer actuators in valves for industrial applications.

  8. KSC-07pd3531

    NASA Image and Video Library

    2007-12-03

    KENNEDY SPACE CENTER, FLA. -- STS-122 Mission Specialist Stanley Love dons his launch and entry suit for a final fitting before space shuttle Atlantis' launch scheduled for 4:31 p.m. EST on Dec. 6. Love will make his first shuttle flight. Atlantis will carry the Columbus Lab, Europe’s largest contribution to the construction of the International Space Station. It will support scientific and technological research in a microgravity environment. Columbus, a program of ESA, is a multifunctional, pressurized laboratory that will be permanently attached to Node 2 of the space station to carry out experiments in materials science, fluid physics and biosciences, as well as to perform a number of technological applications. Photo credit: NASA/Kim Shiflett

  9. Mobile LNG (liquified natural gas) gelator. Final report, July 1980-September 1981

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rudnicki, M.I.; Hoffman, L.C.; Newton, R.A.

    1981-12-01

    Gelled liquified natural gas (GELNG) offers potential safety advantages over LNG in the case of an accidental spill. GELNG has shown reduced spread area, lower vaporization rate, and crack sealing capability relative to the ungelled material. The purpose of this contract was to develop a mobile, continuous gelator which would produce a minimum of one cubic meter per hour of GELNG; previously, GELNG had been produced in small quantities by batch processes. Major achievements under the contract were the design and construction of the mobile gelator, checkout of the system with liquid nitrogen, and testing of the system on LNG.more » GELNG was not produced in the test series.« less

  10. Tunable alumina 2D photonic-crystal structures via biomineralization of peacock tail feathers

    NASA Astrophysics Data System (ADS)

    Jiang, Yonggang; Wang, Rui; Feng, Lin; Li, Jian; An, Zhonglie; Zhang, Deyuan

    2018-04-01

    Peacock tail feathers with subtle periodic nanostructures exhibit diverse striking brilliancy, which can be applied as natural templates to fabricate artificial photonic crystals (PhCs) via a biomineralization method. Alumina photonic-crystal structures are successfully synthesized via an immersion and two-step calcination process. The lattice constants of the artificial PhCs are greatly reduced compared to their natural matrices. The lattice constants are tunable by modifying the final annealing conditions in the biomineralization process. The reflection spectra of the alumina photonic-crystal structures are measured, which is related to their material and structural parameters. This work suggests a facile fabrication process to construct alumina PhCs with a high-temperature resistance.

  11. KSC-07pd3536

    NASA Image and Video Library

    2007-12-03

    KENNEDY SPACE CENTER, FLA. -- STS-122 Mission Specialist Rex Walheim checks the helmet to his launch and entry suit for a final fitting before space shuttle Atlantis' launch scheduled for 4:31 p.m. EST on Dec. 6. Walheim will make his second shuttle flight. Atlantis will carry the Columbus Lab, Europe’s largest contribution to the construction of the International Space Station. It will support scientific and technological research in a microgravity environment. Columbus, a program of ESA, is a multifunctional, pressurized laboratory that will be permanently attached to Node 2 of the space station to carry out experiments in materials science, fluid physics and biosciences, as well as to perform a number of technological applications. Photo credit: NASA/Kim Shiflett

  12. KSC-07pd3533

    NASA Image and Video Library

    2007-12-03

    KENNEDY SPACE CENTER, FLA. -- STS-122 Mission Specialist Rex Walheim checks the helmet to his launch and entry suit for a final fitting before space shuttle Atlantis' launch scheduled for 4:31 p.m. EST on Dec. 6. Walheim will make his second shuttle flight. Atlantis will carry the Columbus Lab, Europe’s largest contribution to the construction of the International Space Station. It will support scientific and technological research in a microgravity environment. Columbus, a program of ESA, is a multifunctional, pressurized laboratory that will be permanently attached to Node 2 of the space station to carry out experiments in materials science, fluid physics and biosciences, as well as to perform a number of technological applications. Photo credit: NASA/Kim Shiflett

  13. KSC-07pd3535

    NASA Image and Video Library

    2007-12-03

    KENNEDY SPACE CENTER, FLA. -- STS-122 Mission Specialist Leland Melvin dons his launch and entry suit for a final fitting before space shuttle Atlantis' launch scheduled for 4:31 p.m. EST on Dec. 6. Melvin will make his first shuttle flight. Atlantis will carry the Columbus Lab, Europe’s largest contribution to the construction of the International Space Station. It will support scientific and technological research in a microgravity environment. Columbus, a program of ESA, is a multifunctional, pressurized laboratory that will be permanently attached to Node 2 of the space station to carry out experiments in materials science, fluid physics and biosciences, as well as to perform a number of technological applications. Photo credit: NASA/Kim Shiflett

  14. KSC-07pd3537

    NASA Image and Video Library

    2007-12-03

    KENNEDY SPACE CENTER, FLA. -- STS-122 Mission Specialist Leland Melvin tests his gloves for a final fitting before space shuttle Atlantis' launch scheduled for 4:31 p.m. EST on Dec. 6. Melvin will make his first shuttle flight. Atlantis will carry the Columbus Lab, Europe’s largest contribution to the construction of the International Space Station. It will support scientific and technological research in a microgravity environment. Columbus, a program of ESA, is a multifunctional, pressurized laboratory that will be permanently attached to Node 2 of the space station to carry out experiments in materials science, fluid physics and biosciences, as well as to perform a number of technological applications. Photo credit: NASA/Kim Shiflett

  15. Sex Instruction and the Construction of Homosexuality in New Zealand, 1920-1965

    ERIC Educational Resources Information Center

    Brickell, Chris

    2005-01-01

    Historical analysis of sex education materials, as well as of the debates that surround them, can shed light upon the construction of sexuality in particular contexts. This article examines some of these materials and debates as a window into the construction of "homosexuality" and "the homosexual" in mid-twentieth century New…

  16. China Report, Economic Affairs

    DTIC Science & Technology

    1985-02-02

    40 Briefs Shanghai Food Industry Production 41 Jiangsu’s Industrial Output Value 41 CONSTRUCTION JINGJI RIBAO Urges Putting Construction First... industry , such as electronics, building materials, chemicals, 13 food and tailoring industries ; communications, such as passenger transportation; as...encourage these enterprises to develop the food , animal feed processing, construction, building materials and energy exploration industries , and help them

  17. 48 CFR 25.1102 - Acquisition of construction.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... construction material is from a designated country other than Bahrain, Mexico, and Oman. (d)(1) Insert the... Bahrain, Mexico, or Oman; or (B) Unmanufactured construction material from a designated country other than Bahrain, Mexico, or Oman. [64 FR 72419, Dec. 27, 1999, as amended at 65 FR 36026, June 6, 2000; 67 FR...

  18. 48 CFR 52.225-22 - Notice of Required Use of American Iron, Steel, and Manufactured Goods-Buy American Statute...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... American Iron, Steel, and Manufactured Goods-Buy American Statute-Construction Materials. 52.225-22 Section... of Required Use of American Iron, Steel, and Manufactured Goods—Buy American Statute—Construction... Iron, Steel, and Manufactured Goods—Buy American Statute—Construction Materials (MAY 2014) (a...

  19. 48 CFR 52.225-21 - Required Use of American Iron, Steel, and Manufactured Goods-Buy American Statute-Construction...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Iron, Steel, and Manufactured Goods-Buy American Statute-Construction Materials. 52.225-21 Section 52... of American Iron, Steel, and Manufactured Goods—Buy American Statute—Construction Materials. As prescribed in 25.1102(e), insert the following clause: Required Use of American Iron, Steel, and Manufactured...

  20. ELWIRA "Plants, wood, steel, concrete - a lifecycle as construction materials": University meets school - science meets high school education

    NASA Astrophysics Data System (ADS)

    Strauss-Sieberth, Alexandra; Strauss, Alfred; Kalny, Gerda; Rauch, Hans Peter; Loiskandl, Willibald

    2016-04-01

    The research project "Plants, wood, steel, concrete - a lifecycle as construction materials" (ELWIRA) is in the framework of the Sparkling Science programme performed by the University of Natural Resources and Life Sciences together with the Billroth Gymnasium in Vienna. The targets of a Sparkling Science project are twofold (a) research and scientific activities should already be transferred in the education methods of schools in order to fascinate high school students for scientific methods and to spark young people's interest in research, and (b) exciting research questions not solved and innovative findings should be addressed. The high school students work together with the scientists on their existing research questions improve the school's profile and the high school student knowledge in the investigated Sparkling Science topic and can lead to a more diverse viewing by the involvement of the high school students. In the project ELWIRA scientists collaborate with the school to quantify and evaluate the properties of classical building materials like concrete and natural materials like plants and woodlogs in terms of their life cycle through the use of different laboratory and field methods. The collaboration with the high school students is structured in workshops, laboratory work and fieldworks. For an efficient coordination/communication, learning and research progress new advanced electronic media like "Moodle classes/courses" have been used and utilized by the high school students with great interest. The Moodle classes are of high importance in the knowledge transfer in the dialogue with the high school students. The research project is structured into four main areas associated with the efficiencies of building materials: (a) the aesthetic feeling of people in terms of the appearance of materials and associated structures will be evaluated by means of jointly developed and collected questionnaires. The analysis, interpretation and evaluation are carried out in close cooperation between the scientists and the high school students, (b) high school students perform classical as well as advanced laboratory testing procedures on the selected materials under the guidance of researchers. They determine a set of mechanical properties and mechanical short and long term performance indicators, such as compression strength, Young modulus, fracture energy etc., (c) field tests on sites are performed to specify climatic characteristics of the examined materials, in order to find out their impact on the surrounding microclimate caused by for instance solar radiation and air temperature, and (d) finally an energy balance (CO2) for the selected materials over their entire life cycle will be carried out by the scientists. These results will provide an important contribution to a sustainable, climate-friendly and resource conserving handling with building materials. The aim of this poster is to present and discuss alternative scientific approaches of scientific working between scientists and high school students and to discuss the learning outcomes already obtained by the high school students within the project "Plants, wood, steel, concrete - a lifecycle as construction materials" ELWIRA.

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