WorldWideScience

Sample records for building materials degradation

  1. THE EFFECT OF DEGRADATION PROCESSES ON THE SERVICEABILITY OF BUILDING MATERIALS OF HISTORIC BUILDINGS

    Directory of Open Access Journals (Sweden)

    Jiří Witzany

    2016-10-01

    Full Text Available The article presents an analysis of degradation processes and partial results of an experimental research into materials and structures exposed to the effects of external environments with an emphasis on the effects of moisture and chemical degradation processes on major mechanical properties of sandstone.

  2. Building Materials

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ Building Materials Sub-council of CCPIT is the other sub-council in construction field. CCPIT Building Materials Sub-council (CCPITBM), as well as CCOIC Build-ing Materials Chamber of Commerce, is au-thorized by CCPIT and state administration of building materials industry in 1992. CCPITBM is a sub-organization of CCPIT and CCOIC.

  3. Analysis of degradation phenomena in ancient, traditional and improved building materials of historical monuments

    Science.gov (United States)

    Figueiredo, M. O.; Silva, T. P.; Veiga, J. P.

    2008-07-01

    A review is presented on constructive techniques plus materials and the processes involved in degradation phenomena observed in two historical monuments: the Zambujeiro dolmen (Portugal) and the Roman Aqueduct of Carthage (Tunisia). Dolmens are particularly impressive megalithic constructions for the dimensions of granite blocks. At Zambujeiro, the upright stones have undergone a catastrophic evolution after the archaeological exploitation due to accelerated weathering through a process apparently distinct from natural granite decay in nearby outcrops. The biological attack of granite minerals by lichen exudates has emphasized the hazardous character of bromine and more has been learnt about construction techniques, namely, the insertion in the mound of an impermeable clay stratum that hinders water penetration into the dolmen chamber. The characterization of original Roman ashlar blocks, including masonry and the diagnosis of Byzantine and medieval reconstruction testimonies in the Aqueduct of Carthage were the object of a detailed study by X-ray diffraction and synchrotron radiation X-ray fluorescence. Traditional constructive techniques and local construction materials were studied and successive historical, modern and recent rehabilitations were reappraised.

  4. Building Materials in Arctic Climate

    DEFF Research Database (Denmark)

    Jensen, Ole Mejlhede

    2005-01-01

    Building in the artic requires special attention on the appropriateness of building materials. The harsh climate makes execution difficult and sets unusual requirements for the pure material properties. In addition, there is a lack of choice of good, natural building materials in the arctic....... This results in high transport costs. The building materials situation in Greenland may potentially be improved by intensifying the reuse of building materials or by promoting the local production of building materials....

  5. Mycotoxins in building materials

    DEFF Research Database (Denmark)

    Nielsen, Kristian Fog; Frisvad, Jens Christian

    2011-01-01

    as in future energy efficient buildings. It brings together different disciplinary points of view on indoor mold, ranging from physics and material science to microbiology and health sciences. The contents have been outlined according to three main issues: Fundamentals, particularly addressing the crucial...... for avoiding adverse health effects is the prevention (or minimization) of persistent dampness and microbial growth on interior surfaces and in building structures. This book aims to describe the fundamentals of indoor mold growth as a prerequisite to tackle mold growth in the existing building stock as well...

  6. BUILDING MATERIALS RECLAMATION PROGRAM

    Energy Technology Data Exchange (ETDEWEB)

    David C. Weggel; Shen-En Chen; Helene Hilger; Fabien Besnard; Tara Cavalline; Brett Tempest; Adam Alvey; Madeleine Grimmer; Rebecca Turner

    2010-08-31

    This report describes work conducted on the Building Materials Reclamation Program for the period of September 2008 to August 2010. The goals of the project included selecting materials from the local construction and demolition (C&D) waste stream and developing economically viable reprocessing, reuse or recycling schemes to divert them from landfill storage. Educational resources as well as conceptual designs and engineering feasibility demonstrations were provided for various aspects of the work. The project was divided into two distinct phases: Research and Engineering Feasibility and Dissemination. In the Research Phase, a literature review was initiated and data collection commenced, an advisory panel was organized, and research was conducted to evaluate high volume C&D materials for nontraditional use; five materials were selected for more detailed investigations. In the Engineering Feasibility and Dissemination Phase, a conceptual study for a regional (Mecklenburg and surrounding counties) collection and sorting facility was performed, an engineering feasibility project to demonstrate the viability of recycling or reuse schemes was created, the literature review was extended and completed, and pedagogical materials were developed. Over the two-year duration of the project, all of the tasks and subtasks outlined in the original project proposal have been completed. The Final Progress Report, which briefly describes actual project accomplishments versus the tasks/subtasks of the original project proposal, is included in Appendix A of this report. This report describes the scientific/technical aspects (hypotheses, research/testing, and findings) of six subprojects that investigated five common C&D materials. Table 1 summarizes the six subprojects, including the C&D material studied and the graduate student and the faculty advisor on each subproject.

  7. Polymeric Materials - introduction and degradation

    DEFF Research Database (Denmark)

    Kontogeorgis, Georgios

    1999-01-01

    These notes support the polymer part of the courses 91742 and 91762 (Materials and Corrosion/degradation of materials) taught in IFAKthey contain a short introduction on group contribution methods for estimating properties of polymers, polymer thermodynamics, viscoelasticity models as well...

  8. Early detection of materials degradation

    Science.gov (United States)

    Meyendorf, Norbert

    2017-02-01

    Lightweight components for transportation and aerospace applications are designed for an estimated lifecycle, taking expected mechanical and environmental loads into account. The main reason for catastrophic failure of components within the expected lifecycle are material inhomogeneities, like pores and inclusions as origin for fatigue cracks, that have not been detected by NDE. However, material degradation by designed or unexpected loading conditions or environmental impacts can accelerate the crack initiation or growth. Conventional NDE methods are usually able to detect cracks that are formed at the end of the degradation process, but methods for early detection of fatigue, creep, and corrosion are still a matter of research. For conventional materials ultrasonic, electromagnetic, or thermographic methods have been demonstrated as promising. Other approaches are focused to surface damage by using optical methods or characterization of the residual surface stresses that can significantly affect the creation of fatigue cracks. For conventional metallic materials, material models for nucleation and propagation of damage have been successfully applied for several years. Material microstructure/property relations are well established and the effect of loading conditions on the component life can be simulated. For advanced materials, for example carbon matrix composites or ceramic matrix composites, the processes of nucleation and propagation of damage is still not fully understood. For these materials NDE methods can not only be used for the periodic inspections, but can significantly contribute to the material scientific knowledge to understand and model the behavior of composite materials.

  9. Material Efficiency of Building Construction

    Directory of Open Access Journals (Sweden)

    Antti Ruuska

    2014-07-01

    Full Text Available Better construction and use of buildings in the European Union would influence 42% of final energy consumption, about 35% of our greenhouse gas emissions and more than 50% of all extracted materials. It could also help to save up to 30% of water consumption. This paper outlines and draws conclusions about different aspects of the material efficiency of buildings and assesses the significance of different building materials on the material efficiency. The research uses an extensive literature study and a case-study in order to assess: should the depletion of materials be ignored in the environmental or sustainability assessment of buildings, are the related effects on land use, energy use and/or harmful emissions significant, should related indicators (such as GHGs be used to indicate the material efficiency of buildings, and what is the significance of scarce materials, compared to the use of other building materials. This research suggests that the material efficiency should focus on the significant global impacts of material efficiency; not on the individual factors of it. At present global warming and greenhouse gas emissions are among the biggest global problems on which material efficiency has a direct impact on. Therefore, this paper suggests that greenhouse gas emissions could be used as an indicator for material efficiency in building.

  10. Frost resistance of building materials

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan De Place

    In this thesis it is shown that the critical degree of saturation is suitable as parameter for the frost resistance of porous building materials. A numerical model for prediction of critical degrees of saturation based on fracture mechanics and phase geometry of two-phase materials, e.g. porous...... materials, has been developed.The importance of the pore structure on the development of stresses in the material during freezing is emphasized. To verify the model, experimental investigations are made on various concretes without air-entrainment and brick tiles with different porosities...

  11. Daylight as a building material

    DEFF Research Database (Denmark)

    Thule Kristensen, Peter; Madsen, Merete

    2005-01-01

    The article draws on examples to chronologically trace the use of daylight as building material in architecture of the 20th and early 21st century. The essay covers works of Mies van der Rohe, Le Corbusier, Erik Bryggman, Rudolf Schwarz, Alvar Aalto, Aldo Rossi, Jørn Utzon, Daniel Libeskind, Peter...

  12. Brief Discussion on Green Building Materials

    Science.gov (United States)

    Cai, Jia-wei; Sun, Jian

    2014-08-01

    With more and more emphasizes on the environment and resources, the concept of green buildings has been widely accepted. Building materials are vectors of architectures, only if green building materials and related technical means are used, can we construct green buildings to achieve the purpose of energy conservation and environmental protection. This paper introduces the relationship between green building materials and green buildings, the current situation of green building materials in China, as well as the measures to accelerate the development of green building materials.

  13. Radon Exhalation Considered in Building Material Standard

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>In order to investigate the relationship between radon exhalation and specific activity of natural nuclides in building material, here different kinds of samples of building materials were measured by the

  14. Preservation of adobe buildings. Study of materials

    Science.gov (United States)

    Velosa, A.; Rocha, F.; Costa, C.; Varum, H.

    2012-04-01

    Adobe buildings are common in the central region of Portugal due to the lack of natural stone in the surrounding area. This type of construction technique lasted until the 20th Century, at which time cementitious materials, with faster hardening and greater structural capacity substituted traditional materials and techniques. Currently, a significant percentage of these buildings is vacant and many are degraded and in need of conservation actions. Adobes from central Portugal are distinctive as they are lightly coloured and made from air lime and quarry sand. Although some adobes were manufactured locally, most were produced almost 'industrially' and sold to nearby regions. In order to preserve this heritage, conservation actions must be undertaken. So as to ensure the adequacy of these actions and compatibility between original materials and new ones, a thorough study of adobe compostion is mandatory. The current study is an initial step in the characterization of earth based construction materials from central Portugal. Adobe samples were collected from residential buildings in two different locations. The determination of the composition of adobe blocks encompassed the determination of the binder fraction and of their chemical composition and also the particle size analysis of the aggregate. For this purpose FRX analysis, acid dissolution and dry sieving were performed. Methylene blue test was also executed in order to determine the clay fraction. Additionally, the mineral composition of powder samples and oriented samples was performed using XRD analysis in order to determine the clay minerals present in the blocks. As adobe blocks are extremely prone to the action of water the Geelong test was undertaken in order to provide information in terms of durability. It was concluded that air lime was generally used in adobe compositions. However, the clay content varies in adobes from different regions, providing distinct durability characteristics to these materials.

  15. Material Corrion/Degradation Database

    Energy Technology Data Exchange (ETDEWEB)

    Kinkead, S.A.

    1999-07-08

    The corrosion of a variety of structural metals and materials is presented. Data on specific material--and for well-studied agents--has been abstracted from the corrosion literature. In addition, limited data on one superacid (so-called ''Magic Acid,'' a mixture of 100% fluorosulfonic acid, HSO{sub 3}F, with 25% (w/w) of antimony pentafluoride (SbF{sub 5}) added) is tabulated.

  16. Self-degradable Cementitious Sealing Materials

    Energy Technology Data Exchange (ETDEWEB)

    Sugama, T.; Butcher, T., Lance Brothers, Bour, D.

    2010-10-01

    A self-degradable alkali-activated cementitious material consisting of a sodium silicate activator, slag, Class C fly ash, and sodium carboxymethyl cellulose (CMC) additive was formulated as one dry mix component, and we evaluated its potential in laboratory for use as a temporary sealing material for Enhanced Geothermal System (EGS) wells. The self-degradation of alkali-activated cementitious material (AACM) occurred, when AACM heated at temperatures of {ge}200 C came in contact with water. We interpreted the mechanism of this water-initiated self-degradation as resulting from the in-situ exothermic reactions between the reactants yielded from the dissolution of the non-reacted or partially reacted sodium silicate activator and the thermal degradation of the CMC. The magnitude of self-degradation depended on the CMC content; its effective content in promoting degradation was {ge}0.7%. In contrast, no self-degradation was observed from CMC-modified Class G well cement. For 200 C-autoclaved AACMs without CMC, followed by heating at temperatures up to 300 C, they had a compressive strength ranging from 5982 to 4945 psi, which is {approx}3.5-fold higher than that of the commercial Class G well cement; the initial- and final-setting times of this AACM slurry at 85 C were {approx}60 and {approx}90 min. Two well-formed crystalline hydration phases, 1.1 nm tobermorite and calcium silicate hydrate (I), were responsible for developing this excellent high compressive strength. Although CMC is an attractive, as a degradation-promoting additive, its addition to both the AACM and the Class G well cement altered some properties of original cementitious materials; among those were an extending their setting times, an increasing their porosity, and lowering their compressive strength. Nevertheless, a 0.7% CMC-modified AACM as self-degradable cementitious material displayed the following properties before its breakdown by water; {approx}120 min initial- and {approx}180 min final

  17. MOISTURE-BUFFERING CHARACTERISTICS OF BUILDING MATERIALS

    Directory of Open Access Journals (Sweden)

    Young Cheol Choi

    2016-05-01

    Full Text Available The humidity level of indoor air is an important factor influencing the air quality and energy consumption of buildings, as well as the durability of building components. Indoor humidity levels depend on several factors, such as moisture sources, air flow, and the adsorption/desorption properties of materials. The moisture-buffering characteristics of building materials that are in contact with indoor air may help moderate the variations of indoor humidity, especially in the summer and winter. In this study, the moisture adsorption/desorption properties of building materials were investigated experimentally and numerically. These properties can be used to characterize the ability of building materials to exchange moisture with the indoor environment. This study indicates that a building material surface resistivity was the main factor creating variations of moisture buffering.

  18. Development of Nuclear Materials and Degradation Database

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Ho Sang [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of); Park, Heung Bae [KEPCO Engineering and Construction Company, Seongnam (Korea, Republic of)

    2010-10-15

    There are about 440 operating nuclear power reactors in the world including 20 units from Korea. The average age of the reactors is more than 20 years and many of them are approaching to their original 30 or 40 years licensing terms. Even though some failures were reported in components or pipes of nuclear power plants (NPPs), these NPPs are considered to be too valuable to stop their operation at the end of design life. Therefore, the long-term operation of NPPs has become a worldwide trend based on technical and economic consideration. In order to ensure safe long-term operation of NPPs, it is increasingly necessary to adopt new approaches to deal with nuclear materials aging and degradation. Proactive Material Degradation Assessment (PMDA) is one of the key elements of these new approaches. Many kinds of background information such as materials and degradation history of components or piping in NPP plant are also needed for PMDA by the experts. Nuclear Materials and Degradation Database is being developed as a part of Nuclear Technology Revolution Project (NTRP) funded by the Ministry of Knowledge Economy (MKE)

  19. Degradable polymeric materials for osteosynthesis: Tutorial

    Directory of Open Access Journals (Sweden)

    D Eglin

    2008-12-01

    Full Text Available This report summarizes the state of the art and recent developments and advances in the use of degradable polymers devices for osteosynthesis. The current generation of biodegradable polymeric implants for bone repair utilising designs copied from metal implants, originates from the concept that devices should be supportive and as “inert” substitute to bone tissue. Today degradable polymeric devices for osteosynthesis are successful in low or mild load bearing applications. However, the lack of carefully controlled randomized prospective trials that document their efficacy in treating a particular fracture pattern is still an issue. Then, the choice between degradable and non-degradable devices must be carefully weighed and depends on many factors such as the patient age and condition, the type of fracture, the risk of infection, etc. The improvement of the biodegradable devices mechanical properties and their degradation behaviour will have to be achieved to broaden their use. The next generation of biodegradable implants will probably see the implementation of the recent gained knowledge in cell-material interactions and cells therapy, with a better control of the spatial and temporal interfaces between the material and the surrounding bone tissue.

  20. [Technology transfer of building materials by ECOMAT

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-01-01

    This report discusses the plan for technology transfer of building materials developed by ECOMAT to the commercial private sector. Some of the materials are briefly discussed like foams, fiber reinforcement, fly ash development, and polymer fillers.

  1. Matching designs with building materials (BYGMATCH)

    DEFF Research Database (Denmark)

    Andersen, Tom

    1999-01-01

    The paper presents a knowledge based approach to mathching design descriptions with proper building materials. It is based on a prototype system developed in KAPPA-PC......The paper presents a knowledge based approach to mathching design descriptions with proper building materials. It is based on a prototype system developed in KAPPA-PC...

  2. Moisture Buffer Value of Building Materials

    DEFF Research Database (Denmark)

    Rode, Carsten; Peuhkuri, Ruut; Time, Berit

    2007-01-01

    When building materials are in contact with indoor air they have some effect to moderate the variations of indoor humidity in occupied buildings. But so far there has been a lack of a standardized quantity to characterize the moisture buffering capability of materials. It has been the objective o...... is a test protocol which expresses how materials should be tested for determination of their Moisture Buffer Value. Finally, the paper presents some of the results of a Round Robin Test on various typical building materials that has been carried out in the project....

  3. (Durability of building materials and components)

    Energy Technology Data Exchange (ETDEWEB)

    Naus, D.J.

    1990-11-27

    The traveler participated in the fourth meeting of RILEM 100-TSL, Techniques for Service Life Prediction,'' and The Fifth International Conference on Durability of Building Materials and Components.'' In addition, the traveler met with staff members at Taywood Engineering Ltd., Electricite de France, and AEA Technology. The meeting pertained to performance of concrete materials in nuclear power plant structures, time variation of concrete material properties, methods for evaluating concrete structures, and modeling to predict the effects of degradation factors on concrete materials. As many of the concrete structures in general civil engineering applications as well as nuclear power plant applications in Europe are aging, there is increasing emphasis on assessing the durability of these structures. Information was provided of direct application to the Structural Aging Program which would not have been available without these visits. Of equal, or possibly more importance, was the individual contacts established at the organizations visited. Each organization was extremely interested in both the approach and scope of the Structural Aging Program and requested that they be informed of progress. The initial steps were taken to cooperate with several of these researchers and this should help the Structural Aging Program keep abreast of related European activities. In summary, information obtained during this trip will benefit the ongoing Structural Aging Program by informing Oak Ridge National Laboratory (ORNL) of the extensive European research programs addressing the durability of concrete structures, and also by forming and strengthening acquaintances with counterparts in other countries, thus enhancing the basis for possible international cooperation.

  4. Sustainable Non-Metallic Building Materials

    Directory of Open Access Journals (Sweden)

    Svetlana Tretsiakova-McNally

    2010-01-01

    Full Text Available Buildings are the largest energy consumers and greenhouse gases emitters, both in the developed and developing countries. In continental Europe, the energy use in buildings alone is responsible for up to 50% of carbon dioxide emission. Urgent changes are, therefore, required relating to energy saving, emissions control, production and application of materials, use of renewable resources, and to recycling and reuse of building materials. In addition, the development of new eco-friendly building materials and practices is of prime importance owing to the growing environmental concerns. This review reflects the key tendencies in the sector of sustainable building materials of a non-metallic nature that have occurred over the past decade or so.

  5. Human exposure to emissions from building materials

    DEFF Research Database (Denmark)

    Kjærgaard, Søren K.; Hauschildt, P.; Pejtersen, J.

    1999-01-01

    Objectives. Reactions to emissions from building matrials were studied in a climate chamber as part of an intervention study in an office building. New and existing flooring materials were compared with regard to comfort and health.Methods. Twenty subjects were exposed four times for six hours...... effects by linoleum and carpet used and that changing to vinyl flooring may reduce these....

  6. Rehabilitation of adobe buildings. Understanding different materials from Portugal

    Science.gov (United States)

    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

  7. Environmental Radiation Hazards of Building Materials

    Directory of Open Access Journals (Sweden)

    Amal A. Nasser

    2012-11-01

    Full Text Available In the last few decades, the importance of studying the environmental impact of building material properties grew. The main focus was to study physical, mechanical and chemical characteristics of building materials. Buildings are the environment that a human spend about 80% of his life. Human exposure to radiation doses emerging from natural and manufactured building materials caused serious diseases. The hazard of radiation doses on human body, especially Radon, was discovered. Radon is produced of the radioactive decay of Uranium and Thorium series. It is a colorless, odorless and tasteless gas. It inters human body by breathing and produces harmful radioactive elements. It has become a goal to know the limits of safety for building materials and to establish green buildings. Health and environmental risks have to take first command in the construction field to take proper precautions to ward off risks. Radon emission was investigated. The radioactive concentration of indoor air may be decreased under the permissible doses by the building geometry variation and other ways as reviewed in this investigation.

  8. Characterization of thermally degraded energetic materials

    Energy Technology Data Exchange (ETDEWEB)

    Renlund, A.M.; Miller, J.C.; Trott, W.M.; Erickson, K.L.; Hobbs, M.L.; Schmitt, R.G.; Wellman, G.W.; Baer, M.R.

    1997-12-31

    Characterization of the damage state of a thermally degraded energetic material (EM) is a critical first step in understanding and predicting cookoff behavior. Unfortunately, the chemical and mechanical responses of heated EMs are closely coupled, especially if the EM is confined. The authors have examined several EMs in small-scale experiments (typically 200 mg) heated in both constant-volume and constant-load configurations. Fixtures were designed to minimize free volume and to contain gas pressures to several thousand psi. The authors measured mechanical forces or displacements that correlated to thermal expansion, phase transitions, material creep and gas pressurization as functions of temperature and soak time. In addition to these real-time measurements, samples were recovered for postmortem examination, usually with scanning electron microscopy (SEM) and chemical analysis. The authors present results on EMs (HMX and TATB), with binders (e.g., PBX 9501, PBX 9502, LX-14) and propellants (Al/AP/HTPB).

  9. Natural Radioactivity of Some Mongolian Building Materials

    CERN Document Server

    Gerbish, S; Ganchimeg, G

    2000-01-01

    The natural radioactivity of some building materials used in cities of Darkhan, Ulaanbaatar and Erdenet in Mongolia was measured by gamma-ray spectrometry with HP-Ge-detector. The radium equivalent concentration and the gamma absorbed dose rate in air, were estimated as the external and internal hazard indices. The results indicate that these materials are not a major source of exposure.

  10. Radioactivity in building materials in Iraq.

    Science.gov (United States)

    Ali, Kamal K

    2012-02-01

    Activity concentrations of (226)Ra, (232)Th and (40)K in 45 samples of different building materials used in Iraq were measured using gamma-spectroscopy system based on high-purity germanium detector with an efficiency of 40 %. Radium equivalent activity, air-absorbed dose rate, annual effective dose, external and internal hazard indices and alpha index due to radon inhalation originating from building materials were measured to assess the potential radiological hazard associated with these building materials. The activity concentrations of the natural radionuclides (226)Ra, (232)Th and 40K were found to range from below detection limit (BDL) to 223.7 ± 9, BDL to 93.0 ± 3 and BDL to 343.1 ± 12, respectively. Values of average radium equivalent activity, air-absorbed dose rate, indoor and outdoor annual effective doses, external and internal hazard indices and alpha index ranged from 6.5 to 124.9, 16.2 to 89.5 (nGy h(-1)), 0.08 to 0.44 mSv, 0.02-0.11 mSv, 0.09 to 0.53, 0.13 to 0.69 and 0.03 to 0.62, respectively. These values indicate a low dose. Therefore, the building materials used in the current study are quite safe to be used as building materials.

  11. Functional materials for energy-efficient buildings

    Directory of Open Access Journals (Sweden)

    Ebert H.-P

    2015-01-01

    Full Text Available The substantial improving of the energy efficiency is essential to meet the ambitious energy goals of the EU. About 40% of the European energy consumption belongs to the building sector. Therefore the reduction of the energy demand of the existing building stock is one of the key measures to deliver a substantial contribution to reduce CO2-emissions of our society. Buildings of the future have to be efficient in respect to energy consumption for construction and operation. Current research activities are focused on the development of functional materials with outstanding thermal and optical properties to provide, for example, slim thermally superinsulated facades, highly integrated heat storage systems or adaptive building components. In this context it is important to consider buildings as entities which fulfill energy and comfort claims as well as aesthetic aspects of a sustainable architecture.

  12. Functional materials for energy-efficient buildings

    Science.gov (United States)

    Ebert, H.-P.

    2015-08-01

    The substantial improving of the energy efficiency is essential to meet the ambitious energy goals of the EU. About 40% of the European energy consumption belongs to the building sector. Therefore the reduction of the energy demand of the existing building stock is one of the key measures to deliver a substantial contribution to reduce CO2-emissions of our society. Buildings of the future have to be efficient in respect to energy consumption for construction and operation. Current research activities are focused on the development of functional materials with outstanding thermal and optical properties to provide, for example, slim thermally superinsulated facades, highly integrated heat storage systems or adaptive building components. In this context it is important to consider buildings as entities which fulfill energy and comfort claims as well as aesthetic aspects of a sustainable architecture.

  13. Nonlinear Dynamics of Structures with Material Degradation

    Science.gov (United States)

    Soltani, P.; Wagg, D. J.; Pinna, C.; Whear, R.; Briody, C.

    2016-09-01

    Structures usually experience deterioration during their working life. Oxidation, corrosion, UV exposure, and thermo-mechanical fatigue are some of the most well-known mechanisms that cause degradation. The phenomenon gradually changes structural properties and dynamic behaviour over their lifetime, and can be more problematic and challenging in the presence of nonlinearity. In this paper, we study how the dynamic behaviour of a nonlinear system changes as the thermal environment causes certain parameters to vary. To this end, a nonlinear lumped mass modal model is considered and defined under harmonic external force. Temperature dependent material functions, formulated from empirical test data, are added into the model. Using these functions, bifurcation parameters are defined and the corresponding nonlinear responses are observed by numerical continuation. A comparison between the results gives a preliminary insight into how temperature induced properties affects the dynamic response and highlights changes in stability conditions of the structure.

  14. Durability of building materials and components

    CERN Document Server

    Delgado, JMPQ

    2013-01-01

    Durability of Building Materials and Components provides a collection of recent research works to contribute to the systematization and dissemination of knowledge related to the long-term performance and durability of construction and, simultaneously, to show the most recent advances in this domain. It includes a set of new developments in the field of durability, service life prediction methodologies, the durability approach for historical and old buildings, asset and maintenance management and on the durability of materials, systems and components. The book is divided in several chapters that intend to be a resume of the current state of knowledge for benefit of professional colleagues.

  15. A drying coefficient for building materials

    DEFF Research Database (Denmark)

    Scheffler, Gregor Albrecht; Plagge, Rudolf

    2009-01-01

    The drying experiment is an important element of the hygrothermal characterisation of building materials. Contrary to other moisture transport experiments as the vapour diffusion and the water absorption test, it is until now not possible to derive a simple coefficient for the drying. However...... coefficient is defined which can be determined based on measured drying data. The correlation of this coefficient with the water absorption and the vapour diffusion coefficient is analyzed and its additional information content is critically challenged. As result, a drying coefficient has been derived...... and defined as a new and independent material parameter. It contains information about the moisture transport properties throughout the wide range of moisture contents from hygroscopic up to saturation. With this new and valuable coefficient, it is now possible to distinguish and select building materials...

  16. Drying kinetics of some building materials

    Directory of Open Access Journals (Sweden)

    A. Moropoulou

    2005-06-01

    Full Text Available Moisture is one of the most deteriorating factors of buildings. The deteriorating effect of moisture occurs mainly during the drying phase, and not in the wetting phase. Appropriate parameters of the drying kinetics are required for the building materials. Environmental factors, such as air temperature, air humidity, and air velocity affect drying. An experimental air dryer of controlled drying air conditions was used to investigate the drying performance of 4 stone materials, 2 bricks and 7 plasters. Drying kinetics was examined at 4 air temperatures, 6 air humidities, and 3 air velocities. A first-order kinetics model was obtained, in which the drying time constant was a function of the drying conditions, and the equilibrium material moisture content was described by the Oswin equation. The parameters of the proposed model were found to be affected strongly by the material and the drying air conditions. The results obtained are very useful in selecting the appropriate plaster to protect existing historic buildings.

  17. Microbial deterioration and degradation of Polymeric materials

    Directory of Open Access Journals (Sweden)

    Krishna Mohan

    2010-12-01

    -bidi-theme-font:minor-bidi;}  Polymeric materials due to its structural versatility are widely used in aerospace applications, aviation and space industries. As they are potential source of carbon and energy for heterotrophic microorganisms including bacteria and fungi in several ways its biodegradation affect these industries. The information on degradability can provide fundamental information facilitating design and life-time analysis of materials. Literature survey shows that polymers which are susceptible to biofilm formation includes paints, adhesives, plastics, rubbers, sealants, FRPCMs, lubricating materials, fuels etc. Even though the understanding of polymer degradation has been advanced in recent years the subject is still inadequately addressed because of the lack of information available. The review focuses on polymer biodeterioration and biodegradation and its mechanisms, the types of microorganisms involved, the reactions of enzymes of importance in the biodegradation of polymers, consequences, of biodegradation, the factors involved in biodegradation of polymers and its prevention and the tests used to evaluate it.

  18. GEOMAGNETIC PROSPECTING FOR DEPOSITS OF BUILDING MATERIALS

    OpenAIRE

    Željko Zagorac; Franjo Šumanovac

    1990-01-01

    Some characteristic examples are given of the magnetic prospecting for the rocks used as building materials. Conclusions are drawn about the applicability of the magnetic method for this purpose. Method proved to be very speedy and inexpensive, it gives important informations on the extension, position and depth of the magnetic rock. The quality of the rock is better determined by other methods (the paper is published in Croatian).

  19. Ozone removal by green building materials

    Energy Technology Data Exchange (ETDEWEB)

    Hoang, Chi P.; Kinney, Kerry A.; Corsi, Richard L. [Department of Civil, Architectural and Environmental Engineering, The University of Texas at Austin, 1 University Station (C1786), Austin, TX 78712 (United States)

    2009-08-15

    Interest in finding out passive ways to keep the variation in the indoor climate within the comfort zone is gaining in popularity. One possible solution is the use of the moisture-buffering property of materials. In this study, the effects of the ventilation system and moisture-buffering properties of the building fabric on the stability of the indoor temperature and humidity are analysed by means of long-term field measurements. Indoor climate measurements were carried out in 170 detached houses (248 rooms). Temperature and relative humidity were measured continuously in bedrooms and living rooms at one-hour intervals over a one-year period. In general, it may be concluded that in this study, the ventilation had a greater effect on the indoor climate than the properties of the building fabric. The dampening effect of hygroscopic materials was remarkably less in the field measurements than it was in simulations in different studies. This indicates that completely non-hygroscopic and fully hygroscopic houses do not exist in reality. The hygroscopic mass of furniture, textiles, etc. is probably a factor that plays a significant role in indoor humidity, as do real air change rates, including window airing. Simulation tools need to be modified in order to be able also to handle furniture, textiles, and books, etc. (author) There is a rapidly expanding market for green building materials. Such materials are intended to be environmentally friendly, with such characteristics as low toxicity, minimal chemical emissions, ability to be recycled, and durability. In addition, green materials often contain recycled and/or bio-based contents. Consequently, some green materials may undergo significant oxidation with potential for reduction of indoor ozone. In this study, 48-L electro-polished stainless steel chambers were used to study the reactive consumption of ozone by ten common green wall, flooring, ceiling, and cabinetry materials (perlite-based ceiling tile, unglazed

  20. Integrating Sustainable Construction Materials to Achieve Green Building

    Directory of Open Access Journals (Sweden)

    Abdelmajeed H. Kasassbeh

    2015-07-01

    Full Text Available Green buildings integrate building materials and methods that promote environmental quality, economic vitality and social benefits through the design, construction and operation of the built environment. This study demonstrates potential actions including material selection that can be implemented to achieve green building. Also, we discuss the importance and environmental impact of sustainable material, the selection criteria of these materials and the different types of sustainable materials in the buildings construction in Jordan.

  1. ICAN Computer Code Adapted for Building Materials

    Science.gov (United States)

    Murthy, Pappu L. N.

    1997-01-01

    The NASA Lewis Research Center has been involved in developing composite micromechanics and macromechanics theories over the last three decades. These activities have resulted in several composite mechanics theories and structural analysis codes whose applications range from material behavior design and analysis to structural component response. One of these computer codes, the Integrated Composite Analyzer (ICAN), is designed primarily to address issues related to designing polymer matrix composites and predicting their properties - including hygral, thermal, and mechanical load effects. Recently, under a cost-sharing cooperative agreement with a Fortune 500 corporation, Master Builders Inc., ICAN was adapted to analyze building materials. The high costs and technical difficulties involved with the fabrication of continuous-fiber-reinforced composites sometimes limit their use. Particulate-reinforced composites can be thought of as a viable alternative. They are as easily processed to near-net shape as monolithic materials, yet have the improved stiffness, strength, and fracture toughness that is characteristic of continuous-fiber-reinforced composites. For example, particlereinforced metal-matrix composites show great potential for a variety of automotive applications, such as disk brake rotors, connecting rods, cylinder liners, and other hightemperature applications. Building materials, such as concrete, can be thought of as one of the oldest materials in this category of multiphase, particle-reinforced materials. The adaptation of ICAN to analyze particle-reinforced composite materials involved the development of new micromechanics-based theories. A derivative of the ICAN code, ICAN/PART, was developed and delivered to Master Builders Inc. as a part of the cooperative activity.

  2. Acoustic Entropy of the Materials in the Course of Degradation

    Directory of Open Access Journals (Sweden)

    Ali Kahirdeh

    2016-07-01

    Full Text Available We report experimental observations on the evolution of acoustic entropy in the course of cyclic loading as degradation occurs due to fatigue. The measured entropy is a result of the materials’ microstructural changes that occur as degradation due to cyclic mechanical loading. Experimental results demonstrate that maximum acoustic entropy emanating from materials during the course of degradation remains similar. Experiments are shown for two different types of materials: Aluminum 6061 (a metallic alloy and glass/epoxy (a composite laminate. The evolution of the acoustic entropy demonstrates a persistent trend over the course of degradation.

  3. Radiation degradation of plastic insulating materials

    Science.gov (United States)

    Bartoníček, B.; Hnát, V.; Janovský, I.; Pejša, R.

    1995-02-01

    Several types of polymeric compounds, used as insulating and sheathing materials of cables, were subjected to accelerated thermal and radiation ageing and to LOCA test. The stability of materials was evaluated via their mechanical properties, namely strain at break.

  4. Concentrated Light for Accelerated Photo Degradation of Polymer Materials

    DEFF Research Database (Denmark)

    Madsen, Morten Vesterager; Tromholt, Thomas; Norrman, Kion;

    2013-01-01

    Concentrated light is used to perform photochemical degradation of polymer solar cell materials with acceleration factors up to 1200. At constant temperature the photon efficiency in regards to photo degradation is constant for 1–150 suns and oxygen diffusion rates are not a limiting factor. Acce...

  5. Polyacylurethanes as Novel Degradable Cell Carrier Materials for Tissue Engineering

    NARCIS (Netherlands)

    Jovanovic, Danijela; Roukes, Frans V.; Loeber, Andrea; Engels, Gerwin E.; van Oeveren, Willem; van Seijen, Xavier J. Gallego; van Luyn, Marja J. A.; Harmsen, Martin C.; Schouten, Arend Jan

    2011-01-01

    Polycaprolactone (PCL) polyester and segmented aliphatic polyester urethanes based on PCL soft segment have been thoroughly investigated as biodegradable scaffolds for tissue engineering. Although proven beneficial as long term implants, these materials degrade very slowly and are therefore not suit

  6. Green Building Construction Thermal Isolation Materials (Rockwool

    Directory of Open Access Journals (Sweden)

    M. Itewi

    2011-01-01

    Full Text Available Problem statement: Building insulation consisting roughly to anything in a structure that is utilizes as insulation for any reason. Thermal insulation in structures is a significant feature to attaining thermal comfort for its tenants. Approach: Insulation decreases unnecessary warmth loss or gain and can reduce the power burdens of heating and cooling structures. It does not automatically having anything to do with problems of sufficient exposure to air and might or might not influence the amount of sound insulation. Results: In a constricted way insulation can just mean the insulation substance used to reduce heat loss, such as: Glass wool, cellulose, polystyrene, rock wool, urethane foam, vermiculite and the earth, but it can also entail a variety of plans and methods used to deal with the chief forms of heat movement like transmission, emission and convection substances. The efficiency of insulation is normally assessed by its R-value. However, an R-value does not allow for the superiority of assembly or narrow green issues for each structure. Building superiority matters comprise insufficient vapor obstructions and troubles with draft-proofing. Additionally, the property and concentration of the insulation substance itself is vital. Fiberglass insulation materials, for example, made out of short fibers of glass covered on top of each other is not as long-lasting as insulation prepared from extended entwined fibers of glass. Conclusion/Recommendations: Rockwool insulation is a kind of insulation that is constructed out of real rocks and minerals. It furthermore is known by the names of mineral wool insulation, stone wool insulation or slag wool insulation. A broad collection of goods can be constructed from Rockwool, because of its outstanding capability to obstruct sound and heat. Rockwool insulation is normally utilized in building assembly, manufacturing plants and in automotive purposes. In this study i proposed to use

  7. Sintered coal ash/flux materials for building materials

    Energy Technology Data Exchange (ETDEWEB)

    Dry, C.; Meier, J.; Bukowski, J. [University of Illinois, Urbana, IL (United States). School of Architecture

    2004-03-01

    An Illinois coal ash, which has metals and a large amount of iron, is considered to be an especially difficult waste for disposal. In the process described in this paper, the high iron and metal content is used to create a building material with special properties. The metals are sequestered. The metals allow a process that creates value-added products, building materials. The products are inexpensively prepared colored, strong, lightweight insulative structural panels. By either sintering in an oven at 725{sup o}C or by adding a flux and sintering at 525{sup o}C, panels are produced which will not leach metals from the ash. The use of an acid with the fly ash as a flux was investigated in comparison with fly ash control samples. The effects of sintering samples at different temperatures and with or without vacuum were also observed. Properties of the samples, including values for strength, water absorption, insulation, and color, are presented from this study.

  8. Straw insulated buildings. Nature building materials; Strohgedaemmte Gebaeude. Naturbaustoffe

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-06-01

    Straw is one of the major agricultural by-products and is mainly used as litter in animal husbandry and to compensate the balance of humus. A relatively recent development is the use of straw bales for the construction of buildings. The brochure under consideration documents the technical development of straw construction in Germany. Possibilities of the use of straw in single family homes up to commercial buildings are described.

  9. Gray energy of building materials; Graue Energie von Baustoffen

    Energy Technology Data Exchange (ETDEWEB)

    Kasser, U.; Poell, M.

    1995-12-31

    The tables of this publication present gray energy data for 500 building materials, chemicals, processes and transportation processes stemming from over 50 sources. Explications and recommendations for the building practice are included. 9 figs., tabs., 59 refs.

  10. Project materials [Commercial High Performance Buildings Project

    Energy Technology Data Exchange (ETDEWEB)

    None

    2001-01-01

    The Consortium for High Performance Buildings (ChiPB) is an outgrowth of DOE'S Commercial Whole Buildings Roadmapping initiatives. It is a team-driven public/private partnership that seeks to enable and demonstrate the benefit of buildings that are designed, built and operated to be energy efficient, environmentally sustainable, superior quality, and cost effective.

  11. Marine fungi: Degraders of poly-3-hydroxyalkanoate based plastic materials

    Directory of Open Access Journals (Sweden)

    Matavulj Milan

    2009-01-01

    Full Text Available The search for new biosynthetic and biodegradable materials to save nonrenewable resources and reduce global pollution problems is an urgent task. Recently, materials like thermoplastic poly-3-hydroxyalkanoates (PHA, have been found synthesized by bacteria as storage materials. The major PHAs synthesized are poly-b-hydroxybutyrate (PHB, poly-b-hydroxyvalerate (PHV and their copolymers. They are already commercially produced and used as BIOPOLTM (ICI, England. Their complete degradability by bacteria has already been shown. Today, oceans and estuaries serve as major landfills, and since fungi are an important part of the degrading microbiota, in order to prove their participation in the degradation process, a simple degradation test suitable for fungi and marine conditions had to be developed. Several solid media based on artificial sea water, differing in the content of non-alkanoate organics and supplemented with 0.1% PHA (or BIOPOLTM as a main source of carbon have been tested. The testing principle consists of clearing the turbid medium in test tube or plates caused by suspended granules of PHA. All media tested supported the growth of fungi. For the discrete and transparent clearing of zones, a mineral medium with 0.01% peptone, 0.01% yeast extract, and 0.1% PHB or BIOPOLTM was finally chosen where the fine and evenly distributed turbidity is accomplished by a specific procedure. This method allows the investigation of degradability of PHA-based plastic materials as well as screening for fungal ability to depolymerise pure PHA homopolymers. Using this medium, 32 strains of marine yeasts and 102 strains of marine mycelial fungi belonging to different systematic and ecological groups were tested for their ability to degrade PHAs. Only about 4% of the strains were able to degrade BIOPOLTM and about 6% depolymerised pure PHB homopolymer. This is in sharp contrast to the results of our previous experiments with 143 strains of terrestrial fungi

  12. Buildings and Health. Educational campaign for healthy buildings. Educational material

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    In recent years health and comfort problems associated with the indoor climate have come to constitute a problem in Sweden. To come to grips with this a nationwide educational campaign on Buildings and Health is being run. It is directed to those involved in planning, project design, construction and management of buildings. The objective is to convey a body of knowledge to the many occupational and professional groups in the construction sector on how to avoid indoor climate problems in homes, schools, offices and other workplaces. The campaign is being run by the Swedish National Board of Housing and Planning and the Swedish Council for Building Research, in co-operation with various organizations and companies in the construction industry, and with municipalities and authorities. The knowledge which is being disseminated through the campaign is summarized in this compendium. figs., tabs.

  13. Materials and system degradation in PEM fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Fowler, D. [Waterloo Univ., ON (Canada). Dept. of Chemical Engineering, Green Energy and Fuel Cell Group

    2007-07-01

    Various degradation processes in fuel cell anodes and cathodes can cause the release of fluoride ions that thin the ionomer membrane and allow more gases to permeate the cell. This presentation provided an overview of reliability modelling techniques used to identify the failure modes of material degradation in fuel cells. A reliability model of a fuel cell stack and hydrogen power system was presented in addition to solution methods for Nafion degradation of the main polymer chain. Changes in the molecular weight of Nafion were discussed. A case study of a model was used to demonstrate that reaction slowed as the ionomer on the cathode degraded. Equations were developed for hydrogen crossover, peroxide production; peroxide destruction; F-ion production; thickness change; diffusion through the gas diffusion layer (GDL); and open circuit voltage (OCV). It was concluded that the OCV durability experiments generated a mechanism for degradation of commercial membranes. The modelling study showed that degradation was related to the permeability of hydrogen to the cathode, and oxygen to the anode. It was concluded that at lower oxygen pressures anode degradation was limited, while at higher pressures anode degradation was more significant. A power point presentation of the University of Waterloo's alternative fuel team provided details of the team's recent research activities. tabs., figs.

  14. Materials Degradation in Light Water Reactors: Life After 60,???

    Energy Technology Data Exchange (ETDEWEB)

    Busby, Jeremy T [ORNL; Nanstad, Randy K [ORNL; Stoller, Roger E [ORNL; Feng, Zhili [ORNL; Naus, Dan J [ORNL

    2008-04-01

    Nuclear reactors present a very harsh environment for components service. Components within a reactor core must tolerate high temperature water, stress, vibration, and an intense neutron field. Degradation of materials in this environment can lead to reduced performance, and in some cases, sudden failure. A recent EPRI-led study interviewed 47 US nuclear utility executives to gauge perspectives on long-term operation of nuclear reactors. Nearly 90% indicated that extensions of reactor lifetimes to beyond 60 years were likely. When polled on the most challenging issues facing further life extension, two-thirds cited plant reliability as the key issue with materials aging and cable/piping as the top concerns for plant reliability. Materials degradation within a nuclear power plant is very complex. There are many different types of materials within the reactor itself: over 25 different metal alloys can be found with can be found within the primary and secondary systems, not to mention the concrete containment vessel, instrumentation and control, and other support facilities. When this diverse set of materials is placed in the complex and harsh environment coupled with load, degradation over an extended life is indeed quite complicated. To address this issue, the USNRC has developed a Progressive Materials Degradation Approach (NUREG/CR-6923). This approach is intended to develop a foundation for appropriate actions to keep materials degradation from adversely impacting component integrity and safety and identify materials and locations where degradation can reasonably be expected in the future. Clearly, materials degradation will impact reactor reliability, availability, and potentially, safe operation. Routine surveillance and component replacement can mitigate these factors, although failures still occur. With reactor life extensions to 60 years or beyond or power uprates, many components must tolerate the reactor environment for even longer times. This may increase

  15. Materials Degradation and Detection (MD2): Deep Dive Final Report

    Energy Technology Data Exchange (ETDEWEB)

    McCloy, John S.; Montgomery, Robert O.; Ramuhalli, Pradeep; Meyer, Ryan M.; Hu, Shenyang Y.; Li, Yulan; Henager, Charles H.; Johnson, Bradley R.

    2013-02-01

    An effort is underway at Pacific Northwest National Laboratory (PNNL) to develop a fundamental and general framework to foster the science and technology needed to support real-time monitoring of early degradation in materials used in the production of nuclear power. The development of such a capability would represent a timely solution to the mounting issues operators face with materials degradation in nuclear power plants. The envisioned framework consists of three primary and interconnected “thrust” areas including 1) microstructural science, 2) behavior assessment, and 3) monitoring and predictive capabilities. A brief state-of-the-art assessment for each of these core technology areas is discussed in the paper.

  16. Building materials in a green economy: A book review

    Directory of Open Access Journals (Sweden)

    Kazi Abdur Rouf

    2013-09-01

    Full Text Available This paper reviews the book ’Building Materials in a Green Economy' written by Brian Milani (2005. The book has eight chapters. This paper deals with the importance of building materials in our lives. The book mainly focuses on the centrality of building materials in all forms of society global indicates how materials are produced, used and reused, which will inevitably affect the quality of lives of those who harvest/create them versus those who benefit from the materials. Brian Milani highlights that the current process for managing building materials is not done in an eco-conscious manner that would entail conservation, maintenance and recycled materials. He addresses how regulation and education will be the key in making changes in the proper management of building materials. Also looks to understand how the building industry informs ‘positional economic development’; warns the readers about the destruction of the Mother Earth by corporations; and manufacturing not eco-friendly building materials and their wastage. Hence, it is important that corporations should produce building materials that are eco-friendly and care for environmental sovereignty.

  17. Energy efficiency of buildings with phase-change materials

    Directory of Open Access Journals (Sweden)

    Lukić Predrag

    2012-01-01

    Full Text Available The construction of energy efficient buildings using innovative building materials such as phase change materials, in addition to improving indoor comfort, energy savings and costs, can be achieved by increasing their market value. Because of its ability to absorb and release energy at predictable temperatures, phase change materials are effective in controlling and maintaining the thermal environment in the building. The use of phase changing materials, materials stored latent energy storage is an effective form of heat. [Projekat Ministarstva nauke Republike Srbije, br. TR36016: Experimental and theoretical investigation of frames and plates with semi-rigid connections from the view of the second order theory and stability analysis

  18. Organic Materials Degradation in Solid State Lighting Applications

    NARCIS (Netherlands)

    Yazdan Mehr, M.

    2015-01-01

    In this thesis the degradation and failure mechanisms of organic materials in the optical part of LED-based products are studied. The main causes of discoloration of substrate/lens in remote phosphor of LED-based products are also comprehensively investigated. Solid State Lighting (SSL) technology i

  19. Two-scale Modelling of material degradation and failure

    Science.gov (United States)

    Aliabadi, Ferri M. H.

    2016-08-01

    It is widely recognized that macroscopic material properties depend on the features of the microstructure. The understanding of the links between microscopic and macroscopic material properties, main topic of Micromechanics, is of relevant technological interest, as it may enable deep understanding of the mechanisms governing materials degradation and failure. Polycrystalline materials are used in many engineering applications. Their microstructure is determined by distribution, size, morphology, anisotropy and orientation of the crystals [1]. At temperature below 0.3-0.5 Tmelting there are no ductile or creep mechanisms and two are the main failure patterns: intergranular, where the damage follows the grain boundaries and transgranular where instead the damage goes through the grain by splitting it into two parts. In this talk a two-scale approach to degradation and failure in polycrystalline materials will be presented. The formulation involves the engineering component level (macro-scale) and the material grain level (micro-scale). The macro-continuum is modelled using two- and three-dimensional boundary element formulation in which the presence of damage is formulated through an initial stress approach to account for the local softening in the neighborhood of points experiencing degradation at the micro-scale. The microscopic degradation is explicitly modelled by associating Representative Volume Elements (RVEs) to relevant points of the macro continuum, for representing the polycrystalline microstructure in the neighbourhood of the selected points. A grainboundary formulation is used to simulate intergranular/transgranular degradation and failure in the microstructure, whose morphology is generated using the Voronoi tessellations. Intergranular/transgranular degradation and failure are modeled through cohesive and frictional contact laws. To couple the two scales, macro-strains are transferred to the RVEs as periodic boundary conditions, while overall macro

  20. Environmental assessment and specification of green building materials

    Energy Technology Data Exchange (ETDEWEB)

    Froeschle, L. M.

    1998-12-01

    The central thesis of this paper is that building with environmentally friendly and `green` materials can lead to significant benefits in terms of improved indoor air quality and a healthy and more productive indoor environment. Recycled content and recyclable products can also help minimize the negative impact on the natural environment by keeping construction materials out of the waste stream, not to mention the cost savings that can be generated when specifying materials with recycled content. Savings in embodied energy is generally less when using recycled content as opposed to raw materials in the manufacture of building materials. The gradual depletion of raw materials will generate increased demand for `greener` products and may, in due course, replace traditional building products. Criteria for the assessment of environmental materials, the `greening` of project specifications, and a process for the environmental specification of building products is also described. 8 refs.

  1. Natural radioactivity measurements of building materials in Baotou, China.

    Science.gov (United States)

    Zhao, Caifeng; Lu, Xinwei; Li, Nan; Yang, Guang

    2012-12-01

    Natural radioactivity due to (226)Ra, (232)Th and (40)K in the common building materials collected from Baotou city of Inner Mongolia, China was measured using gamma-ray spectrometry. The radiation hazard of the studied building materials was estimated by the radium equivalent activity (Ra(eq)), internal hazard index (H(in)) and annual effective dose (AED). The concentrations of the natural radionuclides and Ra(eq) in the studied samples were compared with the corresponding results of other countries. The Ra(eq) values of the building materials are below the internationally accepted values (370 Bq kg(-1)). The values of H(in) in all studied building materials are less than unity. The AEDs of all measured building materials are at an acceptable level.

  2. Polyacylurethanes as Novel Degradable Cell Carrier Materials for Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Arend Jan Schouten

    2011-10-01

    Full Text Available Polycaprolactone (PCL polyester and segmented aliphatic polyester urethanes based on PCL soft segment have been thoroughly investigated as biodegradable scaffolds for tissue engineering. Although proven beneficial as long term implants, these materials degrade very slowly and are therefore not suitable in applications in which scaffold support is needed for a shorter time. A recently developed class of polyacylurethanes (PAUs is expected to fulfill such requirements. Our aim was to assess in vitro the degradation of PAUs and evaluate their suitability as temporary scaffold materials to support soft tissue repair. With both a mass loss of 2.5–3.0% and a decrease in molar mass of approx. 35% over a period of 80 days, PAUs were shown to degrade via both bulk and surface erosion mechanisms. Fourier Transform Infra Red (FTIR spectroscopy was successfully applied to study the extent of PAUs microphase separation during in vitro degradation. The microphase separated morphology of PAU1000 (molar mass of the oligocaprolactone soft segment = 1000 g/mol provided this polymer with mechano-physical characteristics that would render it a suitable material for constructs and devices. PAU1000 exhibited excellent haemocompatibility in vitro. In addition, PAU1000 supported both adhesion and proliferation of vascular endothelial cells and this could be further enhanced by pre-coating of PAU1000 with fibronectin (Fn. The contact angle of PAU1000 decreased both with in vitro degradation and by incubation in biological fluids. In endothelial cell culture medium the contact angle reached 60°, which is optimal for cell adhesion. Taken together, these results support the application of PAU1000 in the field of soft tissue repair as a temporary degradable scaffold.

  3. Degradation Of Cementitious Materials Associated With Saltstone Disposal Units

    Energy Technology Data Exchange (ETDEWEB)

    Flach, G. P; Smith, F. G. III

    2013-03-19

    The Saltstone facilities at the DOE Savannah River Site (SRS) stabilize and dispose of low-level radioactive salt solution originating from liquid waste storage tanks at the site. The Saltstone Production Facility (SPF) receives treated salt solution and mixes the aqueous waste with dry cement, blast furnace slag, and fly ash to form a grout slurry which is mechanically pumped into concrete disposal cells that compose the Saltstone Disposal Facility (SDF). The solidified grout is termed “saltstone”. Cementitious materials play a prominent role in the design and long-term performance of the SDF. The saltstone grout exhibits low permeability and diffusivity, and thus represents a physical barrier to waste release. The waste form is also reducing, which creates a chemical barrier to waste release for certain key radionuclides, notably Tc-99. Similarly, the concrete shell of an SDF disposal unit (SDU) represents an additional physical and chemical barrier to radionuclide release to the environment. Together the waste form and the SDU compose a robust containment structure at the time of facility closure. However, the physical and chemical state of cementitious materials will evolve over time through a variety of phenomena, leading to degraded barrier performance over Performance Assessment (PA) timescales of thousands to tens of thousands of years. Previous studies of cementitious material degradation in the context of low-level waste disposal have identified sulfate attack, carbonation influenced steel corrosion, and decalcification (primary constituent leaching) as the primary chemical degradation phenomena of most relevance to SRS exposure conditions. In this study, degradation time scales for each of these three degradation phenomena are estimated for saltstone and concrete associated with each SDU type under conservative, nominal, and best estimate assumptions. The nominal value (NV) is an intermediate result that is more probable than the conservative

  4. Dielectric material degradation monitoring of dielectric barrier discharge plasma actuators

    Science.gov (United States)

    Hanson, Ronald E.; Houser, Nicole M.; Lavoie, Philippe

    2014-01-01

    It is a known phenomenon that some dielectric materials used to construct plasma actuators degrade during operation. However, the rate at which this process occurs, to what extent, as well as a method to monitor is yet to be established. In this experimental study, it is shown that electrical measurements can be used to monitor changes in the material of the plasma actuators. The procedure we introduce for monitoring the actuators follows from the work of Kriegseis, Grundmann, and Tropea [Kriegseis et al., J. Appl. Phys. 110, 013305 (2011)], who used Lissajous figures to measure actuator power consumption and capacitance. In the present study, we quantify changes in both the power consumption and capacitance of the actuators over long operating durations. It is shown that the increase in the effective capacitance of the actuator is related to degradation (thinning) of the dielectric layer, which is accompanied by an increase in actuator power consumption. For actuators constructed from layers of Kapton® polyimide tape, these changes are self-limiting. Although the polyimide film degrades relatively quickly, the underlying adhesive layer appears to remain intact. Over time, the effective capacitance was found to increase by up to 36%, 25%, and 11% for actuators constructed with 2, 3, and 4 layers of Kapton tape, respectively. A method is presented to prevent erosion of the Kapton dielectric layer using a coating of Polydimethylsiloxane oil. It is shown the application of this treatment can delay the onset of degradation of the Kapton dielectric material.

  5. XRD Investigation of Some Thermal Degraded Starch Based Materials

    Directory of Open Access Journals (Sweden)

    Mihai Todica

    2016-01-01

    Full Text Available The thermal degradation of some starch based materials was investigated using XRD method. The samples were obtained by thermal extrusion of mixtures of different proportions of starch, glycerol, and water. Such materials are suitable for the manufacturing of low pollutant packaging. Thermal degradation is one of the simplest ways to destroy such materials and this process is followed by structural modification of the local ordering of samples, water evaporation, crystallization, oxidation, or destruction of the chemical bonds. These modifications need to be studied in order to reduce to the minimum production of pollutant residues by burning process. XRD measurements show modification of the local ordering of the starch molecules depending on the temperature and initial composition of the samples. The molecular ordering perturbation is more pronounced in samples with low content of starch.

  6. Tactile Response of Building Materials by Tactile Sensor

    OpenAIRE

    岡島, 達雄; 呉, 健丹; 堀越, 哲美; 武田, 雄二; 水谷, 章夫; 川邊, 伸二; ホリコシ, テツミ; ミズタニ, アキオ; カワベ, シンジ; Horikoshi, Tetsumi; Mizutani, Akio; Kawabe, Shinji

    1991-01-01

    The object of this paper is to clarify the tactile response of building materials by tactile sensor. We developed the compact tactile sensor that can measure the physical values of warmth, hardness and roughness of building materials. At a temperature of 2℃, psychological values of warmth, hardness and roughness were obtaind from the physical values of sixty materials by the tactile sensor. The tactile comfort value can be expressed from physical values of warmth, hardness and roughness by th...

  7. Material Connections: Steuart Building, St. Albans School.

    Science.gov (United States)

    Stephens, Suzanne

    1980-01-01

    The addition to the St. Albans campus in Washington, D.C., relates both to the style and the siting of the older "collegiate gothic" school nearby. The mixed-use building contains five classrooms, art and music spaces, and a student lounge. (Author/MLF)

  8. On the degradation of granular materials due to internal erosion

    Science.gov (United States)

    Wang, Xiaoliang; Li, Jiachun

    2015-10-01

    A new state-based elasto-plastic constitutive relationship along with the discrete element model is established to estimate the degradation of granular materials due to internal erosion. Four essential effects of internal erosion such as the force network damage and relaxation are proposed and then incorporated into the constitutive relationship to formulate internal erosion impacts on the mechanical behavior of granular materials. Most manifestations in the degradation of granular materials, such as reduction of peak strength and dilatancy are predicted by the modified constitutive relationship in good agreement with the discrete element method (DEM) simulation. In particular, the sudden reduction of stress for conspicuous mass erosion in a high stress state is captured by force network damage and the relaxation mechanism. It is concluded that the new modified constitutive relationship is a potential theory to describe the degradation of granular materials due to internal erosion and would be very useful, for instance, in the prediction and assessment of piping disaster risk during the flood season.

  9. Degradation of a dental filling material after high caries challenge

    Directory of Open Access Journals (Sweden)

    Márcio Antonio Paraizo

    2004-12-01

    Full Text Available New types of copolymers using monomers which form inorganic polymers network (glass-like and organic networks have been developed, known as ormocers. The aim of this work was to study how a particular dental filling material is degraded when subjected to a caries challenge by using low pH solutions. The supernadants were studied by HPLC to detect the presence of molecules from the resin, while the changes of the material surface were evaluated by contact angle. An organic modified ceromer (ormocer called Definite® (Degussa was tested. Samples were built following manufacturer's instructions. After pH cycles, solutions were injected in a HPLC. The contact angle was obtained using a goniometer after and before the cycles. HPLC results showed material degradation, only detected in acid solutions. Bis-GMA and TEGDMA were detected in Definite® residues. Means and S.D. of contact angle were (p < 0,05: baseline: 85.16° ± 3.90° and after pH cycles: 69.77° ± 7.12°. The authors concluded that an ormocer filling material degraded on a caries simulated environment.

  10. Degradation of cementitious materials associated with salstone disposal units

    Energy Technology Data Exchange (ETDEWEB)

    Flach, G. P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Smith, F. G. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2014-09-01

    The Saltstone facilities at the DOE Savannah River Site (SRS) stabilize and dispose of low-level radioactive salt solution originating from liquid waste storage tanks at the site. The Saltstone Production Facility (SPF) receives treated salt solution and mixes the aqueous waste with dry cement, blast furnace slag, and fly ash to form a grout slurry which is mechanically pumped into concrete disposal cells that compose the Saltstone Disposal Facility (SDF). The solidified grout is termed “saltstone”. Cementitious materials play a prominent role in the design and long-term performance of the SDF. The saltstone grout exhibits low permeability and diffusivity, and thus represents a physical barrier to waste release. The waste form is also reducing, which creates a chemical barrier to waste release for certain key radionuclides, notably Tc-99. Similarly, the concrete shell of a saltstone disposal unit (SDU) represents an additional physical and chemical barrier to radionuclide release to the environment. Together the waste form and the SDU compose a robust containment structure at the time of facility closure. However, the physical and chemical state of cementitious materials will evolve over time through a variety of phenomena, leading to degraded barrier performance over Performance Assessment (PA) timescales of thousands to tens of thousands of years. Previous studies of cementitious material degradation in the context of low-level waste disposal have identified sulfate attack, carbonation influenced steel corrosion, and decalcification (primary constituent leaching) as the primary chemical degradation phenomena of most relevance to SRS exposure conditions. In this study, degradation time scales for each of these three degradation phenomena are estimated for saltstone and concrete associated with each SDU type under conservative, nominal, and best estimate assumptions.

  11. Building Energy Efficiency and the Use of Raw Materials

    Science.gov (United States)

    Yuan, Luo

    To become a country of energy saving, consumption reduction, low carbon emissions and life has become a national policy background, we need to convert conception of architectural aesthetics and make necessary adjustments and consciousness. Techniques and methods of support, or method of the research are still needed in the construction, building energy conservation, the environmental protection, low carbon and recycling methods are taken measures. Developing, finding and adopingt "native" and "primary" processed materials, or in which inject new technology to form new material is an effective approach to ensure more ways from environmental protection, energy-saving building and building materials in such ideas to implement.

  12. Influence of Insulating Materials on Green Building Rating System Results

    Directory of Open Access Journals (Sweden)

    Fabio Bisegna

    2016-09-01

    Full Text Available This paper analyzes the impact of a change in the thermal insulating material on both the energy and environmental performance of a building, evaluated through two different green building assessment methods: Leadership in Energy and Environmental Design (LEED and Istituto per l’innovazione e Trasparenza degli Appalti e la Compatibilità Ambientale (ITACA. LEED is one of the most qualified rating systems at an international level; it assesses building sustainability thanks to a point-based system where credits are divided into six different categories. One of these is fully related to building materials. The ITACA procedure derives from the international evaluation system Sustainable Building Tool (SBTool, modified according to the Italian context. In the region of Umbria, ITACA certification is composed of 20 technical sheets, which are classified into five macro-areas. The analysis was developed on a residential building located in the central Italy. It was built taking into account the principles of sustainability as far as both structural and technical solutions are concerned. In order to evaluate the influence of thermal insulating material, different configurations of the envelope were considered, replacing the original material (glass wool with a synthetic one (expanded polystyrene, EPS and two natural materials (wood fiber and kenaf. The study aims to highlight how the materials characteristics can affect building energy and environmental performance and to point out the different approaches of the analyzed protocols.

  13. Possibilities of Using Cellulose Fibres in Building Materials

    Science.gov (United States)

    Hospodarova, V.; Stevulova, N.; Sicakova, A.

    2015-11-01

    Nowadays, utilization of wastes from agriculture, paper production and building construction is becoming increasingly important due to environmental concerns. Material recycling is a growing trend in the development of building materials; some waste materials can be used in construction as secondary raw materials. The demand for natural non-renewable raw materials is increasing rapidly, therefore, wastes as resources for secondary raw materials can be a good substitute in the production processes. In this way, the shortage of natural raw materials can be supplemented. Construction industry uses secondary raw materials very effectively thereby substituting virgin materials. One of the interesting secondary raw materials is waste coming from natural plant fibres. In this paper, characterization of cellulose fibres from wood pulp, waste paper and their use in cement composites are considered. Technically important parameters of hardened composites are determined and tested (density, water absorbability and compressive strength).

  14. An overview of orthodontic material degradation in oral cavity

    Directory of Open Access Journals (Sweden)

    Chaturvedi T

    2010-01-01

    Full Text Available Various types of metallic orthodontic appliances are used in the management of malocclusion. These appliances are placed in oral environnent under many stresses and variations such as masticatory forces, appliance loading, temperature fluctuations, varieties of ingested food and saliva. These metals undergo electrochemical reactions with the oral environment resulting in dissolution or formation of chemical compounds. Various microorganisms and many aggressive ions containing oral environment can cause material degradation (corrosion and its associated problems during long time exposure. Orthodontic alloys must have excellent corrosion resistance to the oral environment, which is highly important for biocompatibility as well as for orthodontic appliance durability. This article reviews various aspects of corrosion (surface degradation of orthodontic alloys. It explores the emerging research strategies for probing the biocompatibility of materials. During orthodontic treatment, use of nickel free, better corrosion resistance alloys and less use of fluoride containing toothpaste or gel is expected.

  15. Production of mycotoxins on artificially and naturally infested building materials

    DEFF Research Database (Denmark)

    Nielsen, Kristian Fog; Gravesen, S.; Nielsen, P.A.

    1999-01-01

    isolated from water-damaged building materials. Spores from the different isolates of the above mentioned species were inoculated on gypsum board with and without wallpaper and on chipboard with and without wallpaper. Fungal material was scraped off the materials, extracted, and analyzed using high...

  16. Sensory ratings of emissions from nontraditional building materials

    DEFF Research Database (Denmark)

    Krejcirikova, Barbora; Kolarik, Jakub; Peuhkuri, Ruut;

    2016-01-01

    Twenty-five subjects assessed the emissions from building materials: linoleum, cement mortar with and without fly ash, gypsum board and tiles with air cleaning properties and natural organic sheep wool. The ratings were made at different material loadings and in combinations with linoleum....... The results showed that except for natural organic product, increasing loading and combining materials with linoleum increased intensity of odor....

  17. 10 CFR 434.402 - Building envelope assemblies and materials.

    Science.gov (United States)

    2010-01-01

    ... Spaces. The area weighted average thermal transmittance of roofs and also of floors and walls adjacent to... Information. 402.1.1Material Properties. Information on thermal properties, building envelope system.... The overall thermal transmittance of the building envelope shall be calculated in accordance...

  18. Natural radioactivity levels in building materials used in Egypt

    Science.gov (United States)

    Ahmad, Fawzia

    All building materials contain various amounts of radioactive nuclides. The levels of natural radioactivity in 43 selected typical building materials used in the construction of walls, windows and doors were determined. For the first time, the radioactivity of iron was measured, revealing the existence of 60Co. A shielded high-purity germanium detector was used to measure the abundance of 226Ra, 232Th and 40K. The materials examined in this work showed radioactivity levels below the limit estimated from radium equivalent activity for acceptable radiation doses attributable to building materials, except for the fact that one gypsum sample showed higher levels of activity than average world levels. The studied building materials were classified according to the radium equivalent activities, which varied from highest to lowest levels as follows: clay, cement, brick, gypsum except from Abu-Zaabal, sand, wood, iron, glass and hydrated lime The existence of the 137Cs isotope in some building materials was confirmed and its concentration levels were determined (ranging from 0.04 to 21.156 Bq kg-1). The alpha-activity of radon was measured in a number of building materials using CR-39 detectors.

  19. Geochemistry Model Validation Report: Material Degradation and Release Model

    Energy Technology Data Exchange (ETDEWEB)

    H. Stockman

    2001-09-28

    The purpose of this Analysis and Modeling Report (AMR) is to validate the Material Degradation and Release (MDR) model that predicts degradation and release of radionuclides from a degrading waste package (WP) in the potential monitored geologic repository at Yucca Mountain. This AMR is prepared according to ''Technical Work Plan for: Waste Package Design Description for LA'' (Ref. 17). The intended use of the MDR model is to estimate the long-term geochemical behavior of waste packages (WPs) containing U. S . Department of Energy (DOE) Spent Nuclear Fuel (SNF) codisposed with High Level Waste (HLW) glass, commercial SNF, and Immobilized Plutonium Ceramic (Pu-ceramic) codisposed with HLW glass. The model is intended to predict (1) the extent to which criticality control material, such as gadolinium (Gd), will remain in the WP after corrosion of the initial WP, (2) the extent to which fissile Pu and uranium (U) will be carried out of the degraded WP by infiltrating water, and (3) the chemical composition and amounts of minerals and other solids left in the WP. The results of the model are intended for use in criticality calculations. The scope of the model validation report is to (1) describe the MDR model, and (2) compare the modeling results with experimental studies. A test case based on a degrading Pu-ceramic WP is provided to help explain the model. This model does not directly feed the assessment of system performance. The output from this model is used by several other models, such as the configuration generator, criticality, and criticality consequence models, prior to the evaluation of system performance. This document has been prepared according to AP-3.10Q, ''Analyses and Models'' (Ref. 2), and prepared in accordance with the technical work plan (Ref. 17).

  20. Natural radioactivity in building materials used in Changzhi, China.

    Science.gov (United States)

    Yang, Guang; Lu, Xinwei; Zhao, Caifeng; Li, Nan

    2013-08-01

    The natural radioactivity levels of the commonly used building materials collected from Changzhi, China was analysed using gamma-ray spectroscopy. The activity concentrations of (226)Ra, (232)Th and (40)K in the investigated building materials range from 14.6 to 131.2, from 9.9 to 138.8 and from 96.1 to 819.0 Bq kg(-1), respectively. The results were compared with the reported data of other countries and with the worldwide mean activity of soil. The external and internal hazard indices and gamma index were calculated to assess the radiation hazard to residents. The external hazard index of all building materials are less than unity, while the internal hazard and gamma indexes of hollow brick and gravel aggregate exceed unity. The study shows that the investigated hollow brick and gravel aggregate are not suitable for use as building materials in dwellings.

  1. Surface Treatment of Building Materials with Water Repellent Agents

    OpenAIRE

    Wittman, F.H.; Siemes, T.A.J.M.; Verhoef, L.G.W.

    1995-01-01

    Water repellent agents have been applied to proteet building materials and structural elements for thousands ofyears. Initially, natural products, such as oils and fats were used exclusively. More recently, synthetic organic compounds are being developed for special applications.

  2. Gray energy of building materials; Graue Energie von Baustoffen

    Energy Technology Data Exchange (ETDEWEB)

    Kasser, U.; Poell, M. [Buero fuer Umweltchemie, Zurich (Switzerland)

    1995-05-15

    The report highlights the importance of gray energy and discusses the relationship to environmental balances. Literature values for the most important building materials are collated and commented. 9 figs., tabs., 59 refs.

  3. Modeling of electromigration salt removal methods in building materials

    DEFF Research Database (Denmark)

    Johannesson, Björn; Ottosen, Lisbeth M.

    2008-01-01

    A model is established for the prediction of the effect of salt removal of building materials using electromigration. Salt-induced decay of building materials, such as masonry and sandstone, is a serious threat to our cultural heritage. Electromigration of salts from building materials, sensitive...... for salt attack of various kinds, is one potential method to preserve old building envelopes. By establishing a model for ionic multi-species diffusion, which also accounts for external applied electrical fields, it is proposed that an important complement to the experimental tests and that verification...... can be obtained. One important issue is to be able to optimizing the salt removing electromagration method in the field by first studying it theoretically. Another benefit is that models can give some answers concerning the effect of the inner surfaces of the material on the diffusion mechanisms...

  4. Calorimetric methods for the study of fungi on building materials

    OpenAIRE

    Li, Yujing

    2004-01-01

    The aim of this project is to study the fungal growth habits on building materials as a function of humidity, temperature and other environmental parameters. The method of calorimetry is used as a way to quantify fungal activity on building materials. Calorimetry is a general, but sensitive method that can continuously monitor biological processes as a function of environmental conditions. In this report, three different studies are presented: (1) A calorespirometric device was developed and ...

  5. Radioactivity of natural and artificial building materials - a comparative study.

    Science.gov (United States)

    Szabó, Zs; Völgyesi, P; Nagy, H É; Szabó, Cs; Kis, Z; Csorba, O

    2013-04-01

    Building materials and their additives contain radioactive isotopes, which can increase both external and internal radioactive exposures of humans. In this study Hungarian natural (adobe) and artificial (brick, concrete, coal slag, coal slag concrete and gas silicate) building materials were examined. We qualified 40 samples based on their radium equivalent, activity concentration, external hazard and internal hazard indices and the determined threshold values of these parameters. Absorbed dose rate and annual effective dose for inhabitants living in buildings made of these building materials were also evaluated. The calculations are based on (226)Ra, (232)Th and (40)K activity concentrations determined by gamma-ray spectrometry. Measured radionuclide concentrations and hence, calculated indices and doses of artificial building materials show a rather disparate distribution compared to adobes. The studied coal slag samples among the artificial building materials have elevated (226)Ra content. Natural, i.e. adobe and also brick samples contain higher amount of (40)K compared to other artificial building materials. Correlation coefficients among radionuclide concentrations are consistent with the values in the literature and connected to the natural geochemical behavior of U, Th and K elements. Seven samples (coal slag and coal slag concrete) exceed any of the threshold values of the calculated hazard indices, however only three of them are considered to be risky to use according to the fact that the building material was used in bulk amount or in restricted usage. It is shown, that using different indices can lead to different conclusions; hence we recommend considering more of the indices at the same time when building materials are studied. Additionally, adding two times their statistical uncertainties to their values before comparing to thresholds should be considered for providing a more conservative qualification. We have defined radon hazard portion to point

  6. Shielding effectiveness of original and modified building materials

    Directory of Open Access Journals (Sweden)

    T. Frenzel

    2007-06-01

    Full Text Available This contribution deals with the determination of the shielding effectiveness of building materials used for office, factory and government buildings. Besides the examination of standard materials, measurements were also performed on modified materials, e.g. ferro concrete with enhanced shielding effectiveness due to a changed mixture or structure of the reinforcement. The measurements of original and modified materials were carried out in a fully anechoic room (FAR according to IEEE 299-1997 from 80 MHz up to 10 GHz.

  7. Building construction materials effect in tropical wet and cold climates: A case study of office buildings in Cameroon

    Directory of Open Access Journals (Sweden)

    Modeste Kameni Nematchoua

    2016-03-01

    Full Text Available This paper presents the results of an experimental study that was conducted in 15 office buildings in the humid and cold tropics during the working hours of the dry and rainy seasons in Cameroon. This was with the aim to study the effects that local and imported materials had on indoor air quality. To achieve this objective, the adaptive model approach has been selected. In accordance with the conditions of this model, all workers were kept in natural ventilation and, in accordance with the general procedure, a questionnaire was distributed to them, while variables, like air temperature, wind speed, and relative humidity were sampled. The results showed a clear agreement between expected behaviour, in accordance with the characteristics of building construction, and its real indoor ambience once they were statistically analysed. On the other hand, old buildings showed a higher percentage of relative humidity and a lower degree of indoor air temperature. Despite this, local thermal comfort indices and questionnaires showed adequate indoor ambience in each group of buildings, except when marble was used for external tiling. The effect of marble as an external coating helps to improve indoor ambience during the dry season. This is due to more indoor air and relative humidity being accumulated. At the same time, these ambiences are degraded when relative humidity is higher. Finally, these results should be taken cognisance of by architects and building designers in order to improve indoor environment, and overcome thermal discomfort in the Saharan area.

  8. Stress and Damage in Polymer Matrix Composite Materials Due to Material Degradation at High Temperatures

    Science.gov (United States)

    McManus, Hugh L.; Chamis, Christos C.

    1996-01-01

    This report describes analytical methods for calculating stresses and damage caused by degradation of the matrix constituent in polymer matrix composite materials. Laminate geometry, material properties, and matrix degradation states are specified as functions of position and time. Matrix shrinkage and property changes are modeled as functions of the degradation states. The model is incorporated into an existing composite mechanics computer code. Stresses, strains, and deformations at the laminate, ply, and micro levels are calculated, and from these calculations it is determined if there is failure of any kind. The rationale for the model (based on published experimental work) is presented, its integration into the laminate analysis code is outlined, and example results are given, with comparisons to existing material and structural data. The mechanisms behind the changes in properties and in surface cracking during long-term aging of polyimide matrix composites are clarified. High-temperature-material test methods are also evaluated.

  9. Susceptibility of green and conventional building materials to microbial growth.

    Science.gov (United States)

    Mensah-Attipoe, J; Reponen, T; Salmela, A; Veijalainen, A-M; Pasanen, P

    2015-06-01

    Green building materials are becoming more popular. However, little is known about their ability to support or limit microbial growth. The growth of fungi was evaluated on five building materials. Two green, two conventional building materials and wood as a positive control were selected. The materials were inoculated with Aspergillus versicolor, Cladosporium cladosporioides and Penicillium brevicompactum, in the absence and presence of house dust. Microbial growth was assessed at four different time points by cultivation and determining fungal biomass using the N-acetylhexosaminidase (NAHA) enzyme assay. No clear differences were seen between green and conventional building materials in their susceptibility to support microbial growth. The presence of dust, an external source of nutrients, promoted growth of all the fungal species similarly on green and conventional materials. The results also showed a correlation coefficient ranging from 0.81 to 0.88 between NAHA activity and culturable counts. The results suggest that the growth of microbes on a material surface depends on the availability of organic matter rather than the classification of the material as green or conventional. NAHA activity and culturability correlated well indicating that the two methods used in the experiments gave similar trends for the growth of fungi on material surfaces.

  10. Evaluating dynamic building materials: The potential impact of climatically responsive building enclosures

    Science.gov (United States)

    Kienzl, Nico H.

    Despite the great interest and investment in new material technologies and advanced simulation tools, predictions for the potential impact of dynamic envelope systems so far have been based on simulations of the overall building. However, overall building simulations provide limited insights into the behavior of the building envelope since results of these types of simulations are affected by many factors that are independent of or indirectly influenced by the building envelope. Therefore, it is difficult to isolate the impact of the building envelope on building energy consumption independent of building-specific factors such as building geometry, construction, environmental systems, and building use. In order to understand and quantify the dynamic nature of environmentally responsive envelope systems, designers and engineers necessitate a new method that enables the direct evaluation of only the envelope. This method needs to be able to predict the heat transfer through dynamic building envelopes under variable environmental conditions. Ultimately, this new method should help identify the applicability of new technologies early in the design process when detailed information on a building's design or operation are not yet available. This thesis establishes a new method and a validated reference case for the evaluation of climatically responsive building envelopes with dynamic material properties. The method isolates the performance of the building envelope in a building energy simulation model through transformation of a validated BESTEST model. It allows for parametric evaluation of the thermal performance of dynamic building envelopes under a wide range of environmental boundary conditions in comparison to existing reference technologies. This method can serve as a starting point for the critical evaluation of the impact that dynamic envelope systems have on the heat balance of buildings. The method was applied to the evaluation of electrochromic glazing to

  11. Enhanced material classification using turbulence-degraded polarimetric imagery.

    Science.gov (United States)

    Hyde, Milo W; Schmidt, Jason D; Havrilla, Michael J; Cain, Stephen C

    2010-11-01

    An enhanced material-classification algorithm using turbulence-degraded polarimetric imagery is presented. The proposed technique improves upon an existing dielectric/metal material-classification algorithm by providing a more detailed object classification. This is accomplished by redesigning the degree-of-linear-polarization priors in the blind-deconvolution algorithm to include two subclasses of metals--an aluminum group classification (includes aluminum, copper, gold, and silver) and an iron group classification (includes iron, titanium, nickel, and chromium). This new classification provides functional information about the object that is not provided by existing dielectric/metal material classifiers. A discussion of the design of these new degree-of-linear-polarization priors is provided. Experimental results of two painted metal samples are also provided to verify the algorithm's accuracy.

  12. Associations between Fungal Species and Water-Damaged Building Materials

    DEFF Research Database (Denmark)

    Andersen, Birgitte; Frisvad, Jens Christian; Søndergaard, Ib;

    2011-01-01

    melleus, Aspergillus niger, Aspergillus ochraceus, Chaetomium spp., Mucor racemosus, Mucor spinosus, and concrete and other floor-related materials. These results can be used to develop new and resistant building materials and relevant allergen extracts and to help focus research on relevant mycotoxins...

  13. Degradation of chitosan-based materials after different sterilization treatments

    Science.gov (United States)

    San Juan, A.; Montembault, A.; Gillet, D.; Say, J. P.; Rouif, S.; Bouet, T.; Royaud, I.; David, L.

    2012-02-01

    Biopolymers have received in recent years an increasing interest for their potential applications in the field of biomedical engineering. Among the natural polymers that have been experimented, chitosan is probably the most promising in view of its exceptional biological properties. Several techniques may be employed to sterilize chitosan-based materials. The aim of our study was to compare the effect of common sterilization treatments on the degradation of chitosan-based materials in various physical states: solutions, hydrogels and solid flakes. Four sterilization methods were compared: gamma irradiation, beta irradiation, exposure to ethylene oxide and saturated water steam sterilization (autoclaving). Exposure to gamma or beta irradiation was shown to induce an important degradation of chitosan, regardless of its physical state. The chemical structure of chitosan flakes was preserved after ethylene oxide sterilization, but this technique has a limited use for materials in the dry state. Saturated water steam sterilization of chitosan solutions led to an important depolymerization. Nevertheless, steam sterilization of chitosan flakes bagged or dispersed in water was found to preserve better the molecular weight of the polymer. Hence, the sterilization of chitosan flakes dispersed in water would represent an alternative step for the preparation of sterilized chitosan solutions. Alternatively, autoclaving chitosan physical hydrogels did not significantly modify the macromolecular structure of the polymer. Thus, this method is one of the most convenient procedures for the sterilization of physical chitosan hydrogels after their preparation.

  14. Glass-ceramics as building materials

    Directory of Open Access Journals (Sweden)

    Rincón, J. María

    1996-06-01

    Full Text Available Glass-ceramics are materials composed as any ceramic material by several crystalline phases embedded in an amorphous or vitreous matrix, but their manufacture process implies the controlled devitrification or nucleation and growth of phases from an original glass. The original shape of the original glass molded by conventional methods is carried out by using pressing and sintering followed by crystallization steps. By both processing routes are obtained transparent and/or opaque materials, with or without colours, which after adequate control and design of composition and microstructure have numerous domestic and architectonic applications. They can be used as pavements or wall coatings and in various decorative elements. In fact, their use is very extensive in east-European, American and Asian (Japan countries in constructions for covering large surfaces. The greater advantage of the glass-ceramic process is that due to the own process of vitrification allows the incorporation in their structure of a wide range of compositions from mining and industrial residues, such as red muds, ashes, fangos, scraps... which they can in this way not only be inertizated, but furthermore it be converted without risk for the environment into products useful in construction applications, offering to the architect and to the decorator a new range of "eco-materials" with multiple complementary possibilities of the already existing architectural materials in the market.

    Los productos o materiales vitrocerámicos se componen, como cualquier material de tipo cerámico, de una o varias fases cristalinas embebidas en una matriz amorfa o vítrea, pero cuyo proceso de fabricación implica la desvitrificación o nucleación y cristalización controlada de un vidrio original o de partida. En el proceso de obtención de estos materiales se puede conservar la forma original conferida al vidrio de partida por los métodos convencionales de moldeado de vidrios

  15. Building biomedical materials layer-by-layer

    Directory of Open Access Journals (Sweden)

    Paula T. Hammond

    2012-05-01

    Full Text Available In this materials perspective, the promise of water based layer-by-layer (LbL assembly as a means of generating drug-releasing surfaces for biomedical applications, from small molecule therapeutics to biologic drugs and nucleic acids, is examined. Specific advantages of the use of LbL assembly versus traditional polymeric blend encapsulation are discussed. Examples are provided to present potential new directions. Translational opportunities are discussed to examine the impact and potential for true biomedical translation using rapid assembly methods, and applications are discussed with high need and medical return.

  16. BUILDING MATERIALS AND PRODUCTS BASED ON SILICON MANGANESE SLAGS

    Directory of Open Access Journals (Sweden)

    BOLSHAKOV V. I.

    2016-05-01

    Full Text Available Raising of problem. Currently of particular relevance was given to the matter of introduction in manufacture of building materials and products, resource-saving techniques and technologies; integrated use of raw materials and materials that prevent or significantly reduce their harmful impact on the environment. This allows you to recycle hundreds of thousands of tons of the fiery liquid slags of silicon manganese and to develop effective structural materials that can replace metals, non-metallic building materials of natural origin, concretes, cast stone, plastics and refractories. Purpose. The study of the structure and properties of building materials and products from electric furnace slag of silicon manganese. Conclusion. Slags from the smelting of silicon manganese are classified as acidic. Their lime factor is in the range of 0.47–0.52. The composition of the slag located in the heterogeneous region SiO2 near the line of separation of cristobalite spread to the crystallization of wollastonite, according to the ternary system MnO-CaO-SiO2, which in consideration of their stability, allows the development of technology of building materials (gravel, sand, granulated slag, etc. and products (foundation blocks, road slabs, containers for transportation and storage of hazardous waste, and others.

  17. Photocatalytic construction and building materials: From fundamentals to applications

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Jun; Poon, Chi-sun [Department of Civil and Structural Engineering, The Hong Kong Polytechnic University, Hum Hom (China)

    2009-09-15

    Heterogeneous photocatalysis has been intensively studied in recent decades because it only requires photonic energy to activate the chemical conversion contrasting with conventional catalysis which needs heat for thermo-activation. Over the years, the theories for photochemical activity of photocatalyst including photo-induced redox reaction and super-hydrophilic conversion of TiO{sub 2} itself have been established. The progress in academic research significantly promotes its practical applications, including the field of photocatalytic construction and building materials. TiO{sub 2} modified building materials are most popular because TiO{sub 2} has been traditionally used as a white pigment. The major applications of TiO{sub 2} based photocatalytic building materials include environmental pollution remediation, self-cleaning and self-disinfecting. The advantage of using solar light and rainwater as driving force has opened a new domain for environmentally friendly building materials. In this paper, the basic reaction mechanisms on photocatalyst surface under the irradiation of ultraviolet and their corresponding applications in building and construction materials are reviewed. The problems faced in practical applications and the trends for future development are also discussed. (author)

  18. Degradation, fatigue, and failure of resin dental composite materials.

    Science.gov (United States)

    Drummond, J L

    2008-08-01

    The intent of this article is to review the numerous factors that affect the mechanical properties of particle- or fiber-filler-containing indirect dental resin composite materials. The focus will be on the effects of degradation due to aging in different media, mainly water and water and ethanol, cyclic loading, and mixed-mode loading on flexure strength and fracture toughness. Several selected papers will be examined in detail with respect to mixed and cyclic loading, and 3D tomography with multi-axial compression specimens. The main cause of failure, for most dental resin composites, is the breakdown of the resin matrix and/or the interface between the filler and the resin matrix. In clinical studies, it appears that failure in the first 5 years is a restoration issue (technique or material selection); after that time period, failure most often results from secondary decay.

  19. Degradation, Fatigue, and Failure of Resin Dental Composite Materials

    Energy Technology Data Exchange (ETDEWEB)

    Drummond, J.L. (UIC)

    2008-11-03

    The intent of this article is to review the numerous factors that affect the mechanical properties of particle- or fiber-filler-containing indirect dental resin composite materials. The focus will be on the effects of degradation due to aging in different media, mainly water and water and ethanol, cyclic loading, and mixed-mode loading on flexure strength and fracture toughness. Several selected papers will be examined in detail with respect to mixed and cyclic loading, and 3D tomography with multi-axial compression specimens. The main cause of failure, for most dental resin composites, is the breakdown of the resin matrix and/or the interface between the filler and the resin matrix. In clinical studies, it appears that failure in the first 5 years is a restoration issue (technique or material selection); after that time period, failure most often results from secondary decay.

  20. Ozone reactions with indoor materials during building disinfection

    DEFF Research Database (Denmark)

    Poppendieck, D.; Hubbard, H.; Ward, M.

    2007-01-01

    , and particularly after several hours of disinfection, surface reaction resistance dominated the overall resistance to ozone deposition for nearly all materials. Total building disinfection by-products (all carbonyls) were quantified per unit area of each material for the experimental period. Paper, office......There is scant information related to heterogeneous indoor chemistry at ozone concentrations necessary for the effective disinfection of buildings, i.e., hundreds to thousands of ppm. In the present study, 24 materials were exposed for 16 h to ozone concentrations of 1000-1200ppm in the inlet...... streams of test chambers. Initial ozone deposition velocities were similar to those reported in the published literature for much lower ozone concentrations, but decayed rapidly as reaction sites on material surfaces were consumed. For every material, deposition velocities converged to a relatively...

  1. The impact of roofing material on building energy performance

    Science.gov (United States)

    Badiee, Ali

    The last decade has seen an increase in the efficient use of energy sources such as water, electricity, and natural gas as well as a variety of roofing materials, in the heating and cooling of both residential and commercial infrastructure. Oil costs, coal and natural gas prices remain high and unstable. All of these instabilities and increased costs have resulted in higher heating and cooling costs, and engineers are making an effort to keep them under control by using energy efficient building materials. The building envelope (that which separates the indoor and outdoor environments of a building) plays a significant role in the rate of building energy consumption. An appropriate architectural design of a building envelope can considerably lower the energy consumption during hot summers and cold winters, resulting in reduced HVAC loads. Several building components (walls, roofs, fenestration, foundations, thermal insulation, external shading devices, thermal mass, etc.) make up this essential part of a building. However, thermal insulation of a building's rooftop is the most essential part of a building envelope in that it reduces the incoming "heat flux" (defined as the amount of heat transferred per unit area per unit time from or to a surface) (Sadineni et al., 2011). Moreover, more than 60% of heat transfer occurs through the roof regardless of weather, since a roof is often the building surface that receives the largest amount of solar radiation per square annually (Suman, and Srivastava, 2009). Hence, an argument can be made that the emphasis on building energy efficiency has influenced roofing manufacturing more than any other building envelope component. This research project will address roofing energy performance as the source of nearly 60% of the building heat transfer (Suman, and Srivastava, 2009). We will also rank different roofing materials in terms of their energy performance. Other parts of the building envelope such as walls, foundation

  2. ASSESSMENT OF KINETIC PROCESSES OF HARDENING OF BUILDING MATERIALS

    Directory of Open Access Journals (Sweden)

    P. V. Voronov

    2010-12-01

    Full Text Available Problem statement. Kinetic processes are of huge importance when producing building units and operating them as well. However, both technological and operation parameters are determined by the structure of a material under study.Results and conclusions. Kinetics with asymptotic approximation at hardening of building materials is analyzed. The validity of use of new kinetic equation is proved, characterizing harden composite systems and taking into consideration structural and topological peculiarities of new solid-like phase formation directly effecting the evolution of the processes. Results of research of change of strength at solidification a cement-sandy solution with various additives are submitted.

  3. Proceedings of the workshop on cool building materials

    Energy Technology Data Exchange (ETDEWEB)

    Akbari, H.; Fishman, B. [Lawrence Berkeley Lab., CA (United States); Frohnsdorff, G. [National Inst. of Standards and Technology (NEL), Gaithersburg, MD (United States). Building Materials Div.] [eds.

    1994-04-01

    The Option 9, Cool Communities, of the Clinton-Gore Climate Change Action Plan (CCAP) calls for mobilizing community and corporate resources to strategically plant trees and lighten the surfaces of buildings and roads in order to reduce cooling energy use of the buildings. It is estimated that Cool Communities Project will potentially save over 100 billion kilowatt-hour of energy per year corresponding to 27 million tons of carbon per year by the year 2015. To pursue the CCAP`s objectives, Lawrence Berkeley Laboratory (LBL) on behalf of the Department of Energy and the Environmental Protection Agency, in cooperation with the Building and Fire Research Laboratory of the National Institute of Standards and Technology (NIST), organized a one-day meeting to (1) explore the need for developing a national plan to assess the technical feasibility and commercial potential of high-albedo (``cool``) building materials, and if appropriate, to (2) outline a course of action for developing the plan. The meeting took place on February 28, 1994, in Gaithersburg, Maryland. The proceedings of the conference, Cool Building Materials, includes the minutes of the conference and copies of presentation materials distributed by the conference participants.

  4. Transient thermal NDT and E of defects in building materials

    Science.gov (United States)

    Avdelidis, N. P.; Stavrakas, D.; Moropoulou, A.

    2006-04-01

    In this work, infrared thermography (IRT) was used for the investigation of structural materials using the active approach. Four types of building materials were examined; three types of porous stone (from Rhodes, Cyprus, Rethymno - Crete) and one type of marble (Dionysus). Specimens containing self-induced defects of known dimensions and depths were studied. The samples were heated externally (thermal excitation) and thermograms were recorded continuously at the transient phase. Mathematical - thermal modelling enabling the modelling of the investigated subsurface defects, using the thermocalc 3-D software, was also implemented. Then, quantification analysis (i.e. temperature - time plots, as well as thermal contrast curves) from the experimental tests, as well as from the use of thermal modelling runs took place, indicating the thermal behaviour of building materials containing such defects. The results of this research show that IRT can be used for the detection and quantification of defects in structural materials.

  5. Review on phase change materials for building applications

    Directory of Open Access Journals (Sweden)

    Lavinia SOCACIU

    2014-11-01

    Full Text Available In nowadays, the Phase Change Material (PCM is a viable alternative for reducing the energy consumption and for increase the thermal comfort in buildings. The use of PCM in building applications provides the potential to increase the indoor thermal comfort for occupants due to the reduced indoor temperature fluctuations and lower global energy consumption. The possibility to incorporate the PCM into the material of construction for cooling and heating the buildings gained the interest of researchers from all the world because the PCM have a high heat of fusion, meaning it is capable to storing and release large amounts of energy in the form of heat during its melting and solidifying process at a specific temperature.

  6. Selection of material for building pressure vessels and chemical plants

    Energy Technology Data Exchange (ETDEWEB)

    Huppertz, P.H.; Retter, A.

    1979-06-01

    The authors give on extensive survey on the materials used in building pressure vessels and chemical plants for a temperature region of -200 to +1000/sup 0/C. The effect of various influences on the material behaviour is critically examined on the existing control plant, where the differences to foreign control are indicated. NE metals also come into consideration apart from steels, especially with low-temperature application.

  7. VOCs and odors: key factors in selecting `green` building materials?

    Energy Technology Data Exchange (ETDEWEB)

    Coombs, C. [Steven Winter Associates Inc., Norwalk, CT and Washington DC (United States)

    1998-12-01

    The current state of knowledge available for selecting building materials on the basis of emissions of volatile organic compounds (VOCs) and odors is reviewed. The significance of VOCs and odors in building materials is related to their role in influencing indoor air quality. As far as toxicity is concerned, many of the VOCs detected in indoor air are relatively inert when considered singly. They are not however, unimportant because in actual fact they are invariably found in mixtures some of which can be toxic. Although knowledge of VOCs is incomplete, it is important to specify ozone-resistant polymeric building products, i.e. those that are chemically stable and inert to oxidation. In addition to VOCs, attention should also be focused on semi-volatile organic compounds (SVOCs) since they are even more persistent than VOCs and tend to offgas for prolonged periods of time. Similarly, it is reasonable to specify low-odor materials. Inclusion of issues related to complex indoor chemistry, less volatile emissions, in addition to VOCs and odor, should in time result in expanded choices of building materials that promote indoor air quality. 16 refs.,2 tabs.

  8. Self-Organized Construction with Continuous Building Material

    DEFF Research Database (Denmark)

    Heinrich, Mary Katherine; Wahby, Mostafa; Divband Soorati, Mohammad;

    2016-01-01

    Self-organized construction with continuous, structured building material, as opposed to modular units, offers new challenges to the robot-based construction process and lends the opportunity for increased flexibility in constructed artifact properties, such as shape and deformation. As an exampl...

  9. Spectral Signatures of Surface Materials in Pig Buildings

    DEFF Research Database (Denmark)

    Zhang, GuoQiang; Strøm, Jan; Blanke, Mogens;

    2006-01-01

    . In this study, the optical properties of different types of surfaces to be cleaned and the dirt found in finishing pig units were investigated in the visual and the near infrared (VIS-NIR) optical range. Four types of commonly used materials in pig buildings, i.e. concrete, plastic, wood and steel were applied...

  10. High-albedo materials for reducing building cooling energy use

    Energy Technology Data Exchange (ETDEWEB)

    Taha, H.; Sailor, D.; Akbari, H.

    1992-01-01

    One simple and effective way to mitigate urban heat islands, i.e., the higher temperatures in cities compared to those of the surrounds, and their negative impacts on cooling energy consumption is to use high-albedo materials on major urban surfaces such as rooftops, streets, sidewalks, school yards, and the exposed surfaces of parking lots. High-albedo materials can save cooling energy use by directly reducing the heat gain through a building`s envelope (direct effect) and also by lowering the urban air temperature in the neighborhood of the building (indirect effect). This project is an attempt to address high-albedo materials for buildings and to perform measurements of roof coatings. We search for existing methods and materials to implement fighter colors on major building and urban surfaces. Their cost effectiveness are examined and the possible related technical, maintenance, and environmental problems are identified. We develop a method for measuring albedo in the field by studying the instrumentation aspects of such measurements. The surface temperature impacts of various albedo/materials in the actual outdoor environment are studied by measuring the surface temperatures of a variety of materials tested on an actual roof. We also generate an albedo database for several urban surfaces to serve as a reference for future use. The results indicate that high-albedo materials can have a large impact on the surface temperature regime. On clear sunny days, when the solar noon surface temperatures of conventional roofing materials were about 40{degrees}C (72{degrees}F) warmer than air, the surface temperature of high-albedo coatings were only about 5{degrees}C warmer than air. In the morning and in the late afternoon, the high-albedo materials were as cool as the air itself. While conventional roofing materials warm up by an average 0.055{degrees}C/(W m{sup {minus}2}), the high-albedo surfaces warm up by an average 0.015{degrees}C/(W m{sup {minus}2}).

  11. The release of lindane from contaminated building materials.

    Science.gov (United States)

    Volchek, Konstantin; Thouin, Geneviève; Kuang, Wenxing; Li, Ken; Tezel, F Handan; Brown, Carl E

    2014-10-01

    The release of the organochlorine pesticide lindane (γ-hexachlorocyclohexane) from several types of contaminated building materials was studied to assess inhalation hazard and decontamination requirements in response to accidental and/or intentional spills. The materials included glass, polypropylene carpet, latex-painted drywall, ceramic tiles, vinyl floor tiles, and gypsum ceiling tiles. For each surface concentration, an equilibrium concentration was determined in the vapour phase of the surrounding air. Vapor concentrations depended upon initial surface concentration, temperature, and type of building material. A time-weighted average (TWA) concentration in the air was used to quantify the health risk associated with the inhalation of lindane vapors. Transformation products of lindane, namely α-hexachlorocyclohexane and pentachlorocyclohexene, were detected in the vapour phase at both temperatures and for all of the test materials. Their formation was greater on glass and ceramic tiles, compared to other building materials. An empiric Sips isotherm model was employed to approximate experimental results and to estimate the release of lindane and its transformation products. This helped determine the extent of decontamination required to reduce the surface concentrations of lindane to the levels corresponding to vapor concentrations below TWA.

  12. Degradation of human hair keratin scaffold material used to repair injured skeletal muscles of rabbits

    Institute of Scientific and Technical Information of China (English)

    QIAO Dong-fang; LU Yan-meng; FU Wen-yu; PIAO Ying-jie

    2002-01-01

    Objective:To explore the mechanism of the degradation of human hair keratin (HHK) scaffold material implanted in damaged skeletal muscle tissues. Methods: Six New Zealand rabbits with HHK scaffold material implants (composed of 3 different types of HHK material with varied degradation speed) after musclectomy were divided into 3 groups (2 in each group) to observe the degradation of the material at 1, 3, 6weeks after operation. Another rabbit without operation was used as the control group. The degradation of HHK was observed with light microscopy, histochemistry of ubiquitin and electron microscopy. Results:Light microscopy showed that human hair cuticles fell off from the HHK material and emerged, and the macrophagocytes and multinucleate giant cells were attached onto the surface of the material, which became homogeneous at the first postoperative week. The HHK scaffold material was degraded into particles that was phagocytosed by macrophagocytes and multinucleate giant cells at the third week. Ubiquitin enzymatic histochemistry showed that the macrophagocytes and the multinucleate giant cells were positive at the first week. Under electron microscope, HHK scaffold material was degraded into particles, and at the sixth week,part of HHK scaffold material was further degraded. Conclusion: Large mass of the HHK scaffold material is degraded via ubiquitin system, and the resultant particles are phagocytosed and degraded with the cooperation of lysosome and ubiquitin.

  13. High-albedo materials for reducing building cooling energy use

    Energy Technology Data Exchange (ETDEWEB)

    Taha, H.; Sailor, D.; Akbari, H.

    1992-01-01

    One simple and effective way to mitigate urban heat islands, i.e., the higher temperatures in cities compared to those of the surrounds, and their negative impacts on cooling energy consumption is to use high-albedo materials on major urban surfaces such as rooftops, streets, sidewalks, school yards, and the exposed surfaces of parking lots. High-albedo materials can save cooling energy use by directly reducing the heat gain through a building's envelope (direct effect) and also by lowering the urban air temperature in the neighborhood of the building (indirect effect). This project is an attempt to address high-albedo materials for buildings and to perform measurements of roof coatings. We search for existing methods and materials to implement fighter colors on major building and urban surfaces. Their cost effectiveness are examined and the possible related technical, maintenance, and environmental problems are identified. We develop a method for measuring albedo in the field by studying the instrumentation aspects of such measurements. The surface temperature impacts of various albedo/materials in the actual outdoor environment are studied by measuring the surface temperatures of a variety of materials tested on an actual roof. We also generate an albedo database for several urban surfaces to serve as a reference for future use. The results indicate that high-albedo materials can have a large impact on the surface temperature regime. On clear sunny days, when the solar noon surface temperatures of conventional roofing materials were about 40{degrees}C (72{degrees}F) warmer than air, the surface temperature of high-albedo coatings were only about 5{degrees}C warmer than air. In the morning and in the late afternoon, the high-albedo materials were as cool as the air itself. While conventional roofing materials warm up by an average 0.055{degrees}C/(W m{sup {minus}2}), the high-albedo surfaces warm up by an average 0.015{degrees}C/(W m{sup {minus}2}).

  14. Mould growth on building materials under low water activities

    DEFF Research Database (Denmark)

    Nielsen, Kristian Fog; Holm, G.; Uttrup, L.P.;

    2004-01-01

    The influence of relative humidity (RH) and temperature on growth and metabolism of eight microfungi on 21 different types of building material was investigated. The fungi were applied as a dry mixture to the materials, which were incubated at 5degreesC, 10degreesC, 20degreesC and 25degrees......C at three humidity levels in the range 69-95% RH over 4-7 months. The lower limit for fungal growth on wood, wood composites and starch-containing materials was 78% RH at 20-25degreesC and increased to 90% RH at 5degreesC. An RH of 86% was necessary for growth on gypsum board. Ceramic materials supported...... growth at RH > 90%, although 95% RH was needed to yield chemically detectable quantities of biomass. Almost exclusively only Penicillium, Aspergillus and Eurotium (contaminant) species grew on the materials. Production of secondary metabolites and mycotoxins decreased with humidity and the quantities...

  15. Development of materials resistant to metal dusting degradation.

    Energy Technology Data Exchange (ETDEWEB)

    Natesan, K.; Zeng, Z.; Nuclear Engineering Division

    2007-12-07

    The deposition of carbon from carbonaceous gaseous environments is prevalent in many chemical and petrochemical processes such as, hydrogen-, ammonia-, and methanol-reforming systems, syngas production systems, and iron-ore reduction plants. One of the major consequences of carbon deposition is the degradation of structural materials by a phenomenon known as ''metal dusting''. There are two major issues of importance in metal dusting. First is formation of coke and subsequent deposition of coke on metallic structural components. Second is the initiation and subsequent propagation of metal dusting degradation of the structural alloy. In the past, we reported on the mechanism for metal dusting of Fe- and Ni-base alloys. In this report, we present metal dusting data on both Fe- and Ni-base alloys after exposure in high and atmospheric pressure environments that simulate the gas chemistry in operating hydrogen reformers. We have also measured the progression of pits by measuring the depth as a function of exposure time for a variety of Fe- and Ni-base structural alloys. We have clearly established the role of transport of iron in forming a non-protective spinel phase in the initiation process and presence of carbon transfer channels in the oxide scale for the continued propagation of pits, by nano-beam X-ray analysis using the advance photon source (APS), Raman scattering, and SEM/EDX analysis. In this report, we have developed correlations between weight loss and pit progression rates and evaluated the effects of carbon activity, system pressure, and alloy chemistry, on weight loss and pit propagation. To develop pit propagation data for the alloys without incurring substantial time for the initiation of pits, especially for the Ni-base alloys that exhibit incubation times of thousands of hours, a pre-pitting method has been developed. The pre-pitted alloys exhibited pit propagation rates similar to those of materials tested without pre-pitting. We

  16. The effect of atmospheric pollution on building materials

    Science.gov (United States)

    Grossi, C. M.; Brimblecombe, P.

    2002-11-01

    This chapter surveys main effects of atmospheric pollution on building materials. It summarises these effects on stone, bricks, mortar, concrete, glass, metals (iron, zinc, copper, bronze, aluminium, lead and silver), polymers, paints and timber. Special attention is paid to stone because of its extensive use as building material in the cultural heritage. In general, main damaging agent is sulfur dioxide which leads to sulfation of many materials, particularly carbonate-bearing stones. However, the decline of sulfur dioxide in cities means that the recognition of the prime role of this pollutant presents something of a dilemma. It is increasingly necessary to consider other substances that can contribute to material decay e.g. nitrogen oxides, chlorides and ozone, either acting as synergistic to the sulfation reaction or as main decay agents, such as the case of aluminium and polymers. Particulate matter often from diesel vehicles can also accelerate the oxidation of SO2 on the surface (traditionally sulfur dioxide with Fe-rich particles) and blacken the materials surface in the case of soot. These processes contribute to the formation of black-crusts when embedded in the gypsum layer resulting from the material sulfation, but again the rate in the modem atmosphere is a matter of much research.

  17. Assessment of the material properties of a fire damaged building

    Directory of Open Access Journals (Sweden)

    Oladipupo OLOMO

    2012-12-01

    Full Text Available This study identifies a process for assessing the material properties of a fire damaged building so as to determine whether the remains can be utilized in construction or be demolished. Physical and chemical analysis were carried out on concrete and steel samples taken from various elements of the building after thorough visual inspection of the entire building had been conducted. The physical (non-destructive tests included the Schmidt hammer and ultrasonic pulse velocity tests on the concrete samples, tensile strength test on the steel samples and chemical tests involving the assessment of the quantities of cement, sulphates and chloride concentrations in the samples. A redesign of the building elements was also carried out and the results were compared with the existing design. The non-destructive test results indicated compressive strengths as low as 9.9 N/mm2, the tensile strength test indicated a maximum strength of 397.48 N/mm2 and the chemical test indicated chloride contents as high as 0.534 g per gramme of concrete. These properties deviated significantly from standard requirements. Based on these results, it was concluded that the remains of the building should be demolished.

  18. Moisture measurements in building materials with microwaves; Rakennusmateriaalien kosteusmittauksia mikroaalloilla

    Energy Technology Data Exchange (ETDEWEB)

    Kaeaeriaeinen, H.; Rudolph, M.; Schaurich, D.; Wiggenhauser, H. [VTT Building Technology, Espoo (Finland). Construction and Facility Management

    1998-12-01

    In order to assess the condition and evaluate the reliability of buildings and structures, it is essential to establish the moisture condition of the floor and other structural elements of the building. NDT-methods are increasingly being used for such moisture measurements because they do not cause any damage to the building under investigation. Microwave transmission is one of the NDT-methods and has been in use for several years. In this report, the applicability of the microwave method for measuring moisture in different building materials was investigated. This method has been successfully used at BAM for repeated moisture measurements in brick and sandstone material. This project also included other materials, such as concrete, sand, gravel, insulation and wood. At the same time, information was gathered about in situ moisture determination of building materials with a microwave moisture measuring system. The equipment used in this research has been developed at BAM over the last few years. The method requires two parallel boreholes in the specimen in which two microwave antennae can be moved. The moisture content in the material can be calculated from the microwave intensity transmitted between the two boreholes. Moisture profiles along the boreholes can be obtained by moving the antennae in steps along the length of the boreholes and taking measurements at each step. Special care must be taken while drilling the holes for the antennae, as this process must not affect the moisture condition in the specimen, and the boreholes must be made as parallel to each other as possible. The microwave frequencies used in the laboratory measurements ranged from 8 to 16,5 GHz in steps of 0,5 GHz. The diameters of the antennae were between 7 and 9 mm, and of the boreholes between 8 and 12 mm. Except for the concrete specimen, all the specimens were measured using plastic tubes in the boreholes. The moisture content measured by the microwave technique was verified by the

  19. Drying and wetting of building materials and components

    CERN Document Server

    2014-01-01

    This book, Drying and Wetting of Building Materials and Components, provides a collection of recent contributions in the field of drying and wetting in porous building materials. The main benefit of the book is that it discusses some of the most important topics related to the drying and wetting processes, namely, innovations and trends in drying science and technology, drying mechanism and theory, equipment, advanced modelling, complex simulation and experimentation. At the same time, these topics will be going to the encounter of a variety of scientific and engineering disciplines. The book is divided in several chapters that intend to be a resume of the current state of knowledge for benefit of professional colleagues.

  20. Valorisation of phosphogypsum as building material: Radiological aspects

    Directory of Open Access Journals (Sweden)

    Tayibi, H.

    2011-12-01

    Full Text Available Nowadays, alternative uses of phosphogypsum (PG in the building industry are being considered in several countries; however, the natural radioactivity level in the PG could be a restriction for those uses. United States Environmental Protection Agency (US-EPA classified PG as Technologically Enhanced Naturally Occurring Radioactive Material (TENORM. This drawback could be avoided controlling its percentage in the cement preparation and the radionuclides content in the other raw materials used in its production, and calculating the activity concentration index (I in the final by-products. The valorization of PG as a building material has been studied, from a radiological point of view, by developing a new stabilisation/solidification process. PG is incorporated within a polymeric sulphur matrix, obtaining a concrete-like material, which presents lower natural radioactive content than the initial PG. The 226Ra content of this material ranged between 26-27 Bq·kg-1 and it is quite similar to that of common Spanish building materials.

    Actualmente, en muchos países se está contemplando el uso alternativo del fosfoyeso (PG en la industria de la construcción, aunque su contenido en radionucleidos naturales puede presentar ciertas restricciones para dicha aplicación (material clasificado por la US-EPA como TENORM: “Technologically Enhanced Naturally Occurring Materials. No obstante, estos inconvenientes podrían paliarse controlando el porcentaje del PG y los niveles de radioactividad en las materias primas a incorporar al cemento y calculando el índice de concentración de actividad (I en los productos finales. La valorización del PG como material de construcción se ha estudiado en este trabajo desde el punto de vista radiológico, desarrollando un nuevo proceso de estabilización/solidificación, obteniéndose un material de características similares al cemento y que presenta menor contenido de radionucleidos naturales que el

  1. Optimal thermographic procedures for moisture analysis in building materials

    Science.gov (United States)

    Rosina, Elisabetta; Ludwig, Nicola

    1999-09-01

    The presence of moisture in building materials causes damage second only to structural one. NDT are successfully applied to map moisture distribution, to localize the source of water and to determine microclimatic conditions. IR Thermography has the advantage of non-destructive testing while it allows to investigate large surfaces. The measures can be repeated in time to monitor the phenomenon of raising water. Nevertheless the investigation of moisture in walls is one of the less reliable application of Thermography IR applied to cultural heritage preservation. The temperature of the damp areas can be colder than dry ones, because of surface evaporation, or can be warmer, because of the higher thermal inertia of water content versus building materials. The apparent discrepancies between the two results are due to the different microclimatic conditions of the scanning. Aim of the paper is to describe optimal procedures to obtain reliable maps of moisture in building materials, at different environmental and microclimatic conditions. Another goal is the description of the related energetic phenomena, which cause temperature discontinuities, and that are detected by thermography. Active and passive procedures are presented and compared. Case studies show some examples of procedures application.

  2. Dynamic solar radiation control in buildings by applying electrochromic materials

    Energy Technology Data Exchange (ETDEWEB)

    Jelle, B.P.; Gustavsen, A.

    2010-07-01

    Full text: Smart windows like electrochromic windows (ECWs) are windows which are able to regulate the solar radiation throughput by application of an external voltage. The ECWs may decrease heating, cooling and electricity loads in buildings by admitting the optimum level of solar energy and daylight into the buildings at any given time, e.g. cold winter climate versus warm summer climate demands. In order to achieve as dynamic and flexible solar radiation control as possible, the ECWs may be characterized by a number of solar radiation glazing factors, i.e. ultraviolet solar transmittance, visible solar transmittance, solar transmittance, solar material protection factor, solar skin protection factor, external visible solar reflectance, internal visible solar reflectance, solar reflectance, solar absorbance, emissivity, solar factor and colour rendering factor. Comparison of these solar quantities for various electrochromic material and window combinations and configurations enables one to select the most appropriate electrochromic materials and ECWs for specific buildings. Measurements and calculations were carried out on two different electrochromic window devices. (Author)

  3. Radon exhalation rate of some building materials used in Egypt.

    Science.gov (United States)

    Maged, A F; Ashraf, F A

    2005-09-01

    Indoor radon has been recognized as one of the health hazards for mankind. Common building materials used for construction of houses, which are considered as one of the major sources of this gas in indoor environment, have been studied for exhalation rate of radon. Non-nuclear industries, such as coal fired power plants or fertilizer production facilities, generate large amounts of waste gypsum as by-products. Compared to other building materials waste gypsum from fertilizer production facilities (phosphogypsum) shows increased rates of radon exhalation. In the present, investigation solid state alpha track detectors, CR-39 plastic detectors, were used to measure the indoor radon concentration and the radon exhalation rates from some building materials used in Egypt. The indoor radon concentration and the radon exhalation rate ranges were found to be 24-55 Bq m(-3 )and 11-223 mBq m(-2) h(-1), respectively. The effective dose equivalent range for the indoor was found 0.6-1.4 mSv y(-1). The equilibrium factor between radon and its daughters increased with the increase of relative humidity.

  4. Natural radioactivity measurements in building materials used in Samsun, Turkey.

    Science.gov (United States)

    Tufan, M Çagatay; Disci, Tugba

    2013-01-01

    In this study, radioactivity levels of 35 different samples of 11 commonly used building materials in Samsun were measured by using a gamma spectrometry system. The analysis carried out with the high purity Germanium gamma spectrometry system. Radioactivity concentrations of (226)Ra, (232)Th and (40)K range from 6 to 54 Bq kg(-1), 5 to 88 Bq kg(-1) and 6 to 1070 Bq kg(-1), respectively. From these results, radium equivalent activities, gamma indexes, absorbed dose rates and annual effective doses were calculated for all samples. Obtained results were compared with the available data, and it was concluded that all the investigated materials did not have radiological risk.

  5. Bioinspired Design of Building Materials for Blast and Ballistic Protection

    Directory of Open Access Journals (Sweden)

    Yu-Yan Sun

    2016-01-01

    Full Text Available Nacre in abalone shell exhibits high toughness despite the brittle nature of its major constituent (i.e., aragonite. Its specific structure is a major contributor to the energy absorption capacity of nacre. This paper reviews the mechanisms behind the performance of nacre under shear, uniaxial tension, compression, and bending conditions. The remarkable combination of stiffness and toughness on nacre can motivate the development of bioinspired building materials for impact resistance applications, and the possible toughness designs of cement-based and clay-based composite materials with a layered and staggered structure were discussed.

  6. Pathology of Building Materials in Historic Buildings. Relationship Between Laboratory Testing and Infrared Thermography

    OpenAIRE

    Lerma, C.; Mas, Á.; Gil,E.; Vercher, J.; Peñalver, M. J.

    2014-01-01

    Study of historic buildings requires a pathology analysis of the construction materials used in order to define their conservation state. Usually we can find capillary moisture, salt crystalli-zation or density differences by deterioration. Sometimes this issue is carried out by destructive testing which determine materials’ physical and chemical characteristics. However, they are unfavorable regarding the building’s integrity, and they are sometimes difficult to implement. This paper present...

  7. Radon exhalation from building materials for decorative use.

    Science.gov (United States)

    Chen, Jing; Rahman, Naureen M; Abu Atiya, Ibrahim

    2010-04-01

    Long-term exposure to radon increases the risk of developing lung cancer. There is considerable public concern about radon exhalation from building materials and the contribution to indoor radon levels. To address this concern, radon exhalation rates were determined for 53 different samples of drywall, tile and granite available on the Canadian market for interior home decoration. The radon exhalation rates ranged from non-detectable to 312 Bq m(-2) d(-1). Slate tiles and granite slabs had relatively higher radon exhalation rates than other decorative materials, such as ceramic or porcelain tiles. The average radon exhalation rates were 30 Bq m(-2) d(-1) for slate tiles and 42 Bq m(-2) d(-1) for granite slabs of various types and origins. Analysis showed that even if an entire floor was covered with a material having a radon exhalation rate of 300 Bq m(-2) d(-1), it would contribute only 18 Bq m(-3) to a tightly sealed house with an air exchange rate of 0.3 per hour. Generally speaking, building materials used in home decoration make no significant contribution to indoor radon for a house with adequate air exchange.

  8. Luminescence dosimetry using building materials and personal objects.

    Science.gov (United States)

    Göksu, H Y; Bailiff, I K

    2006-01-01

    There is a growing public awareness of the risk of accidental radiation exposure due to ageing nuclear power installations, illegal dumping of nuclear waste and terrorist activities, and of the consequential health risks to populations in addition to social and economic disturbance extending beyond national boundaries. In the event of catastrophic incidents where no direct radiation monitoring data are available, the application of retrospective dosimetry techniques such as luminescence may be employed with materials from the immediate environment to confirm values of cumulative gamma dose to compare with or augment computational modeling calculations. Application of the method to post-Chernobyl studies has resulted in the development of new procedures using fired building materials with the capability to measure cumulative doses owing to artificial sources of gamma radiation as low as 20 mGy. Combined with Monte Carlo simulations of photon transport, values of cumulative dose in brick can be presented in a form suitable for use in dose-reconstruction efforts. Recent investigations have also shown that certain types of cementitious building material, including concrete, mortar and plaster, and personal objects in the form of telephone cards containing microchips and dental ceramics have the potential to be used for retrospective dosimetry. Examples of the most recent research concerning new materials and examples of application to sites in the Former Soviet Union are discussed.

  9. Experimental Study on the Comparison of the Material Properties of Glass Wool Used as Building Materials

    Directory of Open Access Journals (Sweden)

    Kyoung-Woo KIM

    2014-04-01

    Full Text Available Artificial mineral fibers such as glass wool or stone wool are commonly used in building walls, ceilings and floors as a major insulation material for buildings. Among the material properties of building materials, thermal conductivity, the sound absorption coefficient, compressibility, and dynamic stiffness are regarded as important performance requirements since they directly affect the thermal and acoustic properties of the building. This study measured the changes of the thermal and acoustical performances of glass wool that was actually installed for a long time to the outer wall of a building as an insulation material through a comparison with recently produced glass wool. The results showed that the measured thermal conductivities of the old and the new specimens both rise with an increase of temperature, showing quite similar results in both specimens over temperature ranges of (0 – 20 ºC. The noise reduction coefficient decreased by 0.1 in the old specimen and the difference of the compressibilities in both specimens was shown to be 7.32 mm. The dynamic stiffness of the old specimen was found to be 1.28 MN/m3 higher than that of the new specimen.DOI: http://dx.doi.org/10.5755/j01.ms.20.1.3714

  10. Natural Radioactivity in some building materials from Spain

    Energy Technology Data Exchange (ETDEWEB)

    Miro, C. [Universidad de Extremadura (UEX), 10071-Caceres (Spain); Madruga, M.J.; Reis, M. [Instituto Superior Tecnico, Universidade de Lisboa, Campus Tecnologico e Nuclear, 2695-066 Bobadela LRS (Portugal)

    2014-07-01

    Studies of natural radiation are of great importance because it is the main source of exposure of human kind. Building materials is one of the sources which cause direct radiation exposure because of their radium, thorium and potassium content. The aim of this work is to measure gamma activity due to {sup 40}K, {sup 226}Ra and {sup 232}Th in samples of commonly used as a building materials in Spain. Cement, gypsum, plaster, marble, slates, granite and wood had been analysed. These materials are used for private and public building. Radium equivalent activities (Ra{sub eq}) and various hazard indices were also calculated to assess the radiation hazard. Results were also compared with the data available in the literature for other countries of the world. Cement, gypsum and plaster samples were collected from hardware stores. Marble, slates and granite samples were taken from different quarries. And the wood samples were taken from eucalyptus trees from forest. Activity concentrations {sup 40}K-, {sup 226}Ra- and {sup 232}Th-activity was determined by gamma spectrometry using a HPGe coaxial detector. The results show that the range of average values of the activity concentrations due to {sup 40}K, {sup 226}Ra and {sup 232}Th were found between 37 and 1340 Bq/kg, 0.007 and 104 Bq/kg, and <0.005 and 75 Bq/kg, respectively. Maxima values were obtained in granite. Radium equivalent activities range from 3.7 Bq/kg to 283 Bq/kg, calculated in wood and granite, respectively. Therefore all the samples showed Raeq activities within the limit, 370 Bq/kg, set by UNSCEAR. Values of external hazard index for all samples under investigation are below the unity, while the internal hazard index for granite exhibits a value around the unity. Acknowledgements to the financial support of the Junta de Extremadura (project PRI09A092 and FEDER-group GRU09053). (authors)

  11. Radiological risk of building materials using homemade airtight radon chamber

    Energy Technology Data Exchange (ETDEWEB)

    Khalid, Norafatin; Majid, Amran Ab.; Yahaya, Redzuwan; Yasir, Muhammad Samudi [Nuclear Science Programme, School of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor Darul Ehsan (Malaysia)

    2014-02-12

    Soil based building materials known to contain various amounts of natural radionuclide mainly {sup 238}U and {sup 232}Th series and {sup 40}K. In general most individuals spend 80% of their time indoors and the natural radioactivity in building materials is a main source of indoor radiation exposure. The internal exposure due to building materials in dwellings and workplaces is mainly caused by the activity concentrations of short lived {sup 222}Radon and its progenies which arise from the decay of {sup 226}Ra. In this study, the indoor radon concentration emanating from cement brick, red-clay brick, gravel aggregate and Portland cement samples were measured in a homemade airtight radon chamber using continuous radon monitor 1029 model of Sun Nuclear. Radon monitor were left in the chamber for 96 hours with an hour counting time interval. From the result, the indoor radon concentrations for cement brick, red-clay brick, gravel aggregate and Portland cement samples determined were 396 Bq m{sup −3}, 192 Bq m{sup −3}, 176 Bq m{sup −3} and 28 Bq m{sup −3}, respectively. The result indicates that the radon concentration in the studied building materials have more than 100 Bq m{sup −3} i.e. higher than the WHO action level except for Portland cement sample. The calculated annual effective dose for cement brick, red-clay brick, gravel aggregate and Portland cement samples were determined to be 10 mSv y{sup −1}, 4.85 mSv y{sup −1}, 4.44 mSv y{sup −1} and 0.72 mSv y{sup −1}, respectively. This study showed that all the calculated effective doses generated from indoor radon to dwellers or workers were in the range of limit recommended ICRP action levels i.e. 3 - 10 mSv y{sup −1}. As consequences, the radiological risk for the dwellers in terms of fatal lifetime cancer risk per million for cement brick, red-clay brick, gravel aggregate and Portland cement were calculated to be 550, 267, 244 and 40 persons respectively.

  12. Numerical Investigation of a Moisture Evaporation Model in Building Materials

    CERN Document Server

    Amirkhanov, I V; Pavlish, M; Puzynina, T P; Puzynin, I V; Sarhadov, I

    2005-01-01

    The properties of a model of moisture evaporation in a porous building material of a rectangular form proposed in [1] are investigated. Algorithms of solving a nonlinear diffusion equation with initial and boundary conditions simulating the dynamic distribution of moisture concentration, calculation of coefficients of a polynomial describing transport of moisture with usage of experimental measurement of moisture concentration in a sample are developed and investigated. Research on the properties of the model is carried out depending on the degree of the polynomial, a set of its coefficients, and the quantity of the used experimental data.

  13. Assessment on urban soil pollution by biocides from building materials

    DEFF Research Database (Denmark)

    Bollmann, Ulla E.; Vollertsen, Jes; Bester, Kai

    2015-01-01

    . Based on a monitoring study of stormwater runoff from a residential catchment as well as direct façade runoff analysis, the present study was assessing the pollution of urban soil to biocides from building material. The stormwater runoff of a residential catchment in Silkeborg (Denmark) was monitored...... from a freshly painted or rendered house, it is obvious that a huge part is actually draining directly to the soil and not to the sewer system. Consequently, the soil in urban areas is exposed to stormwater highly polluted by biocides which might affect the microbial community there....

  14. Potential Damage to Modern Building Materials from 21st Century Air Pollution

    Directory of Open Access Journals (Sweden)

    Peter Brimblecombe

    2010-01-01

    Full Text Available The evolution of damage to building materials has been estimated for the 21st century, with a particular focus on aluminum, zinc, copper, plastic, paint, and rubber in urban areas. We set idealized air pollution and climates to represent London and Prague across the period 1950–2100. Environmental parameters were used to estimate future recession, corrosion, and loss of properties through published damage or dose-response functions. The 21st century seems to provide a less aggressive environment for stone and metals than recent times. Improvements in air quality are the most relevant drivers for this amelioration. Changes in climate predicted for the 21st century do not alter this picture. On the other hand, polymeric materials, plastic, paint, and rubber might show slightly increased rates of degradation, to some extent the result of enhanced oxidant concentrations, but also the possibility of contributions from more solar radiation.

  15. Development of Composite PCMs by Incorporation of Paraffin into Various Building Materials

    Directory of Open Access Journals (Sweden)

    Shazim Ali Memon

    2015-02-01

    Full Text Available In this research, we focused on the development of composite phase-change materials (CPCMs by incorporation of a paraffin through vacuum impregnation in widely used building materials (Kaolin and ground granulated blast-furnace slag (GGBS. The composite PCMs were characterized using environmental scanning electron microscopy (ESEM, Fourier transform infrared spectroscopy (FT-IR, differential scanning calorimetry (DSC and thermogravimetric analysis (TGA techniques. Moreover, thermal performance of cement paste composite PCM panels was evaluated using a self-designed heating system. Test results showed that the maximum percentage of paraffin retained by Kaolin and GGBS was found to be 18% and 9%, respectively. FT-IR results show that CPCMs are chemically compatible. The phase-change temperatures of CPCMs were in the human comfort zone, and they possessed considerable latent-heat storage capacity. TGA results showed that CPCMs are thermally stable, and they did not show any sign of degradation below 150 °C. From thermal cycling tests, it was revealed that the CPCMs are thermally reliable. Thermal performance tests showed that in comparison to the control room model, the room models prepared with CPCMs reduced both the temperature fluctuations and maximum indoor center temperature. Therefore, the prepared CPCMs have some potential in reducing peak loads in buildings when applied to building facade.

  16. Decreased bio-inhibition of building materials due to transport of biocides

    NARCIS (Netherlands)

    Erich, S.J.F.; Mendoza, S.M.; Floor, W.; Hermanns, S.P.M.; Homan, W.J.; Adan, O.C.G.

    2011-01-01

    Bio-inhibition of buildings and structures is an important issue. In many cases building materials have biocides added to prevent growth of micro-organisms. Growth of microorganisms on building materials has several negative effects; (1) Aesthetic damage, e.g. fungi, algae grow on the material, resu

  17. Photocatalytic degradation of sunscreen active ingredients mediated by nanostructured materials

    Science.gov (United States)

    Soto-Vazquez, Loraine

    Water scarcity and pollution are environmental issues with terrible consequences. In recent years several pharmaceutical and personal care products, such as sunscreen active ingredients, have been detected in different water matrices. Its recalcitrant behavior in the environment has caused controversies and generated countless questions about its safety. During this research, we employed an advanced oxidation process (photocatalysis) to degrade sunscreen active ingredients. For this study, we used a 3x3 system, evaluating three photocatalysts and three different contaminants. From the three catalysts employed, two of them were synthesized. ZnO nanoparticles were obtained using zinc acetate dihydrated as the precursor, and TiO2 nanowires were synthesized from titanium tetrachloride precursor. The third catalyst employed (namely, P25) was obtained commercially. The synthesized photocatalysts were characterized in terms of the morphology, elemental composition, crystalline structure, elemental oxidation states, vibrational modes and surface area, using SEM-EDS, XRD, XPS, Raman spectroscopy and BET measurements, respectively. The photocatalysts were employed during the study of the degradation of p-aminobenzoic acid, phenylbenzimidazole sulfonic acid, and benzophenone-4. In all the cases, at least 50% degradation was achieved. P25 showed degradation efficiencies above 90%, and from the nine systems, 7 of them degraded at least 86%.

  18. Microencapsulated Phase Change Composite Materials for Energy Efficient Buildings

    Science.gov (United States)

    Thiele, Alexander

    This study aims to elucidate how phase change material (PCM)-composite materials can be leveraged to reduce the energy consumption of buildings and to provide cost savings to ratepayers. Phase change materials (PCMs) can store thermal energy in the form of latent heat when subjected to temperatures exceeding their melting point by undergoing a phase transition from solid to liquid state. Reversibly, PCMs can release this thermal energy when the system temperature falls below their solidification point. The goal in implementing composite PCM walls is to significantly reduce and time-shift the maximum thermal load on the building in order to reduce and smooth out the electricity demand for heating and cooling. This Ph.D. thesis aims to develop a set of thermal design methods and tools for exploring the use of PCM-composite building envelopes and for providing design rules for their practical implementation. First, detailed numerical simulations were used to show that the effective thermal conductivity of core-shell-matrix composites depended only on the volume fraction and thermal conductivity of the constituent materials. The effective medium approximation reported by Felske (2004) was in very good agreement with numerical predictions of the effective thermal conductivity. Second, a carefully validated transient thermal model was used to simulate microencapsulated PCM-composite walls subjected to diurnal or annual outdoor temperature and solar radiation flux. It was established that adding microencapsulated PCM to concrete walls both substantially reduced and delayed the thermal load on the building. Several design rules were established, most notably, (i) increasing the volume fraction of microencapsulated PCM within the wall increases the energy savings but at the potential expense of mechanical properties [1], (ii) the phase change temperature leading to the maximum energy and cost savings should equal the desired indoor temperature regardless of the climate

  19. Building Blocks Incorporating Waste Materials Bound with Bitumen

    Directory of Open Access Journals (Sweden)

    Thanaya I.N.A.

    2010-01-01

    Full Text Available This paper described an investigation and evaluation which was carried out in the United Kingdom-UK, on the properties of masonry building block materials that incorporate waste materials, namely: steel slag, crushed glass, coal fly ash, rice husk ash (RHA, incinerator sewage sludge ash (ISSA, municipal solid waste incinerator bottom ash (MSWIBA or shortened as IBA, bound with bitumen or asphalt, named as Bitublock. The binder used was 50 pen bitumen. The properties of the blocks evaluated were: compressive strength, density, porosity, initial rate of suction (IRS, creep, and volume stability. It was found that the Bitublock performance can be improved by optimizing porosity and curing regime. Compaction level of 2 MPa and curing regime of 200°C for 24 hours gave satisfactory bitublock performances that at least comparable to concrete block found in the United Kingdom (UK. The Volume stability (expansion of the unit is affected by environment relative humidity.

  20. ANALYSIS OF BIODEGRABILITY OF DEGRADABLE/BIODEGRADABLE PLASTIC MATERIAL IN CONTROLLED COMPOSTING ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    Dana Adamcová

    2016-09-01

    Full Text Available We have obtained eight degradable/biodegradable materials based on starch (certified compostable, sample 4–7, HDPE mixed with totally degradable plastic additive (TDPA, sample 2 and polyethylene with the addition of pro-oxidant additive (d2w, sample 1. Composition of sample 3 has not been reported. The materials have been tested as to the rate and character of their degradability/biodegradability in controlled composting conditions. Experiment explored also the effect of degradation/biodegradation of plastic bags on compost quality. The material of the original samples was subjected to assessment using the Nicolet 6700 FT-IR spectrometer, the outcome thereof was obtaining infrared spectra of the samples. For further specification the original samples were tested using the thermogravimetrical analysis. The texture of the foils at different stages of degradation is presented in the Scanning Electron Microscope (SEM photographs. Plastic bags certified as compostable have degraded in laboratory conditions and their degradation had no impact on the quality and features of compost. Selected samples (4, 6 showed significant erosion on surface when subjected to the SEM analysis. Samples labeled (by their producers as 100% degradable (samples 1, 2, 3 did not show any visual signs of degradation and the process of degradation had no impact on the quality and features of compost. Only one of the samples (sample 1 showed certain erosion of surface when submitted for the SEM analysis.

  1. Radiological restrictions of using red mud as building material additive.

    Science.gov (United States)

    Gu, Hannian; Wang, Ning; Liu, Shirong

    2012-09-01

    Red mud remains as residue from the processing of bauxite using different methods. The chemical composition of red mud varies widely with respect to the types of bauxite ore and processing parameters. Red mud samples from Guizhou, China, were investigated using a X-ray fluorescence spectroscope, a quadrupole inductively coupled plasma mass spectrometer and a electron probe micro-analyzer. The results showed that red mud consisted of eight main chemical components--CaO, Al(2)O(3), SiO(2), Fe(2)O(3), TiO(2), Na(2)O, K(2)O and MgO--and dozens of trace elements, including natural radioactive elements, such as uranium and thorium. Gamma spectrometric analysis showed that the values of internal exposure index I (Ra) and external exposure index I (γ) of Guizhou red mud were 1.1-2.4 and 2.3-3.5 respectively. Thus, it should not be used as a main building material indiscriminately. The amount of red mud from Guizhou when it is used for main building materials in China should be less than 28-44%.

  2. 15 CFR 270.321 - Entry and inspection of property where building components, materials, artifacts, and records...

    Science.gov (United States)

    2010-01-01

    ... building components, materials, artifacts, and records with respect to a building failure are located. 270... of property where building components, materials, artifacts, and records with respect to a building... building components, materials, artifacts and records with respect to a building failure are...

  3. State of the art on historic building insulation materials and retrofit strategies

    DEFF Research Database (Denmark)

    Blumberga, Andra; Kass, Kristaps; Kamendere, Edite

    2016-01-01

    This report provides an analysis and evaluation of a state-of-the-art of internal insulation materials and methods for application in historic buildings, and review on methods, tools and guidelines used as decision making tools for implementation of internal insulation in historic buildings....... Historic buildings in RIBuild represent all types of protected1 and non-protected buildings built before 1945. The survey is limited to buildings with heavy walls (stone, brick, timber framing), thus excluding wooden buildings....

  4. Building capacity for national carbon measurements for reducing emissions from deforestation and forest degradation

    Science.gov (United States)

    Goetz, S. J.; Laporte, N.; Horning, N.; Pelletier, J.; Jantz, P.; Ndunda, P.

    2014-12-01

    Many tropical countries are now working on developing their strategies for reducing emissions from deforestation and forest degradation, including activities that result in conservation or enhancement of forest carbon stocks and sustainable management of forests to effectively decrease atmospheric carbon emissions (i.e. REDD+). A new international REDD+ agreement is at the heart of recent negotiations of the parties to the UN Framework Convention on Climate Change (UNFCCC). REDD+ mechanisms could provide an opportunity to not only diminish an important source of emissions, but also to promote large-scale conservation of tropical forests and establish incentives and opportunities to alleviate poverty. Most tropical countries still lack basic information for developing and implementing their forest carbon stock assessments, including the extent of forest area and the rate at which forests are being cleared and/or degraded, and the carbon amounts associated with these losses. These same countries also need support to conduct integrated assessments of the most promising approaches for reducing emissions, and in identifying those policy options that hold the greatest potential while minimizing potential negative impacts of REDD+ policies. The WHRC SERVIR project in East Africa is helping to provide these data sets to countries via best practice tools and methods to support cost effective forest carbon monitoring solutions and more informed decision making processes under REDD+. We will present the results of our capacity building activites in the region and planned future efforts being coordinated with the NASA-SERVIR Hub in Kenya to support to REDD+ decision support.

  5. PCM-enhanced building components an application of phase change materials in building envelopes and internal structures

    CERN Document Server

    Kosny, Jan

    2015-01-01

    Presenting an overview of the use of Phase Change Materials (PCMs) within buildings, this book discusses the performance of PCM-enhanced building envelopes. It reviews the most common PCMs suitable for building applications, and discusses PCM encapsulation and packaging methods. In addition to this, it examines a range of PCM-enhanced building products in the process of development as well as examples of whole-building-scale field demonstrations. Further chapters discuss experimental and theoretical analyses (including available software) to determine dynamic thermal and energy performance ch

  6. Pathology of Building Materials in Historic Buildings. Relationship Between Laboratory Testing and Infrared Thermography

    Directory of Open Access Journals (Sweden)

    Lerma, C.

    2014-03-01

    Full Text Available Study of historic buildings requires a pathology analysis of the construction materials used in order to define their conservation state. Usually we can find capillary moisture, salt crystalli-zation or density differences by deterioration. Sometimes this issue is carried out by destructive testing which determine materials’ physical and chemical characteristics. However, they are unfavorable regarding the building’s integrity, and they are sometimes difficult to implement. This paper presents a technique using infrared thermography to analyze the existing pathology and has the advantage of being able to diagnose inaccessible areas in buildings. The results obtained by this technique have been compared with those obtained in the laboratory, in order to validate this study and thus to extrapolate the methodology to other buildings and materials.El estudio de edificios históricos requiere un análisis de la patología de los materiales de construcción empleados para poder definir su estado de conservación. Habitualmente nos encontramos con humedades por capilaridad, cristalización de sales o diferencias de densidad por deterioro. En ocasiones esto se lleva a cabo mediante ensayos destructivos que nos determinan las características físicas y químicas de los materiales, pero que resultan desfavorables respecto a la integridad del edificio, y en ocasiones resulta complejo llevarlos a cabo. Este trabajo presenta una técnica para analizar la patología existente mediante el empleo de termografía infrarroja con la ventaja de poder diagnosticar zonas de difícil acceso en los edificios. Para validar este estudio se han comparado los resultados obtenidos mediante esta técnica con los alcanzados en el laboratorio. De esta forma podemos extrapolar la metodología empleada a otros edificios y materiales.

  7. Towards proteomic analysis of milk proteins in historical building materials

    Science.gov (United States)

    Kuckova, S.; Crhova, M.; Vankova, L.; Hnizda, A.; Hynek, R.; Kodicek, M.

    2009-07-01

    The addition of proteinaceous binders to mortars and plasters has a long tradition. The protein additions were identified in many sacral and secular historical buildings. For this method of peptide mass mapping, three model mortar samples with protein additives were prepared. These samples were analysed fresh (1-2 weeks old) and after 9 months of natural ageing. The optimal duration of tryptic cleavage (2 h) and the lowest amount of material needed for relevant analysis of fresh and weathered samples were found; the sufficient amounts of weathered and fresh mortars were set to 0.05 and 0.005 g. The list of main tryptic peptides coming from milk additives (bovine milk, curd, and whey), their relative intensities and theoretical amino acid sequences assignment is presented. Several sequences have been "de novo" confirmed by mass spectrometry.

  8. Millennium-long damage to building materials in London.

    Science.gov (United States)

    Brimblecombe, Peter; Grossi, Carlota M

    2009-02-01

    Damage functions from a range of sources are used to estimate deterioration of carbonate stone, iron and copper, in addition to the rate of blackening of stone surfaces in London across the period 1100-2100 CE. Meteorological and pollution input is available for only a relatively short part of this span, so non-instrumental weather records and modelled pollution are utilised for historic values, while future climate is adapted from the HadCM3A2 model output and pollution assessed from likely regulatory trends. The results from the different damage functions compare reasonably well showing comparable changes in damage rates with time. A potential square-root dependence of change in deposition velocity of SO2 to limestone suggests a possible overestimate of damage when pollution is high. Deterioration is especially intense from the 1700s. It is difficult to be certain whether the corrosion of copper accelerated as early as this or it developed in the 20th century. Nevertheless all the functions predict a decline in copper corrosion from the end of the 20th century. A blackening function was developed to relate elemental carbon concentration and the colour of deposited particulate matter to blackening rate, which suggests that soiling was particularly rapid in the late 19th century. The increase and subsequent decrease in damage to building materials is interpreted in terms of a Kuznets curve. The centuries where pollution controlled damage to durable building material seems to be over. Weathering, in a changing climate may have the greatest impact in the future.

  9. Main chain acid-degradable polymers for the delivery of bioactive materials

    Science.gov (United States)

    Frechet, Jean M. J. [Oakland, CA; Standley, Stephany M [Evanston, IL; Jain, Rachna [Milpitas, CA; Lee, Cameron C [Cambridge, MA

    2012-03-20

    Novel main chain acid degradable polymer backbones and drug delivery systems comprised of materials capable of delivering bioactive materials to cells for use as vaccines or other therapeutic agents are described. The polymers are synthesized using monomers that contain acid-degradable linkages cleavable under mild acidic conditions. The main chain of the resulting polymers readily degrade into many small molecules at low pH, but remain relatively stable and intact at physiological pH. The new materials have the common characteristic of being able to degrade by acid hydrolysis under conditions commonly found within the endosomal or lysosomal compartments of cells thereby releasing their payload within the cell. The materials can also be used for the delivery of therapeutics to the acidic regions of tumors and other sites of inflammation.

  10. Photoconversion of gasified organic materials into biologically-degradable plastics

    Science.gov (United States)

    Weaver, Paul F.; Maness, Pin-Ching

    1993-01-01

    A process is described for converting organic materials (such as biomass wastes) into a bioplastic suitable for use as a biodegradable plastic. In a preferred embodiment the process involves thermally gasifying the organic material into primarily carbon monoxide and hydrogen, followed by photosynthetic bacterial assimilation of the gases into cell material. The process is ideally suited for waste recycling and for production of useful biodegradable plastic polymer.

  11. Photoconversion of gasified organic materials into biologically-degradable plastics

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, P.F.; Pinching Maness.

    1993-10-05

    A process is described for converting organic materials (such as biomass wastes) into a bioplastic suitable for use as a biodegradable plastic. In a preferred embodiment the process involves thermally gasifying the organic material into primarily carbon monoxide and hydrogen, followed by photosynthetic bacterial assimilation of the gases into cell material. The process is ideally suited for waste recycling and for production of useful biodegradable plastic polymer. 3 figures.

  12. Rice Husk Ash Sandcrete Block as Low Cost Building Material

    Directory of Open Access Journals (Sweden)

    S.P.Sangeetha,

    2016-06-01

    Full Text Available Concrete is a widely used construction material for various types of structures due to its structural stability and strength. The construction industry is today consuming more than 400 million tonnes of concrete every year .Most of the increase in cement demand will be met by the use of supplementary cementing materials, as each ton of Portland cement clinker production is associated with similar amount of CO2 emission, which is a major source of global warming. Partial replacement of ordinary Portland cement with mineral admixtures like fly ash, ground granulated blast furnace slag, silica fume, metakaolin, Rice husk Ash (RHA,etc with plasticizers eliminates these drawbacks. The use of rice husk modifies the physical qualities of fresh cement paste as well as microstructure of paste after hardening. By burning the rice husk under a uncontrolled temperature in the atmosphere, a highly reactive RHA was obtained and the ash was utilized as a supplementary cementing material. This paper presents the effects of using Rice Husk Ash (RHA as a partial cement replacement material in mortar mixes. This work is based on an experimental study of mortar made with replacement of Ordinary Portland Cement (OPC with 10%, 20% 30% & 40% RHA. The properties investigated were the compressive strength, setting time, consistency, workability and specific gravity. Finally, a cost analysis was also done to compare the efficiency of rice husk ash sandcrete blocks. From the test results it can be concluded that rice husk ash can be utilized in day today life of manufacturing building blocks which are more economical and more eco-friendly than the cement concrete blocks which are produced now-a-days.

  13. Advanced Materials for RSOFC Dual Operation with Low Degradation

    Energy Technology Data Exchange (ETDEWEB)

    Eric, Tang; Tony, Wood; Sofiane, Benhaddad; Casey, Brown; Hongpeng, He; Jeff, Nelson; Oliver, Grande; Ben, Nuttall; Mark, Richards; Randy, Petri

    2012-12-27

    Reversible solid oxide fuel cells (RSOFCs) are energy conversion devices. They are capable of operating in both power generation mode (SOFC) and electrolysis modes (SOEC). RSOFC can integrate renewable production of electricity and hydrogen when power generation and steam electrolysis are coupled in a system, which can turn intermittent solar and wind energy into "firm power." In this DOE EERE project, VPS continuously advanced RSOFC cell stack technology in the areas of endurance and performance. Over 20 types of RSOFC cells were developed in the project. Many of those exceeded performance (area specific resistance less than 300 mohmcm2) and endurance (degradation rate less than 4% per 1000 hours) targets in both fuel cell and electrolysis modes at 750C. One of those cells, RSOFC-7, further demonstrated the following: Steady-state electrolysis with a degradation rate of 1.5% per 1000 hours. Ultra high current electrolysis over 3 A/cm2 at 75% water electrolysis efficiency voltage of 1.67 V. Daily SOFC/SOEC cyclic test of over 600 days with a degradation rate of 1.5% per 1000 hours. Over 6000 SOFC/SOEC cycles in an accelerated 20-minute cycling with degradation less than 3% per 1000 cycles. In RSOFC stack development, a number of kW-class RSOFC stacks were developed and demonstrated the following: Steady-state electrolysis operation of over 5000 hours. Daily SOFC/SOEC cyclic test of 100 cycles. Scale up capability of using large area cells with 550 cm2 active area showing the potential for large-scale RSOFC stack development in the future. Although this project is an open-ended development project, this effort, leveraging Versa Power Systems' years of development experience, has the potential to bring renewable energy RSOFC storage systems significantly closer to commercial viability through improvements in RSOFC durability, performance, and cost. When unitized and deployed in renewable solar and wind installations, an RSOFC system can enable higher

  14. Environmentally suitable building materials. Grey energy and sustainability of buildings; Umweltgerechte Baustoffe. Graue Energie und Nachhaltigkeit von Gebaeuden

    Energy Technology Data Exchange (ETDEWEB)

    Pueschel, Danny; Teller, Matthias (eds.)

    2013-02-01

    The editors of the book under consideration present a compilation of contributions on environmentally suitable building materials from different perspectives. It provides an overview of 'Grey Energy' and a total energy balance of buildings. The most contributions are based on lectures of a symposium in April, 2011, in the Knobelsdorff School in Berlin-Spandau (Federal Republic of Germany).

  15. Bioactivity and degradability of hybrids nano-composites materials with great application as bone tissue substitutes

    Energy Technology Data Exchange (ETDEWEB)

    Sánchez-Téllez, D.A.; Téllez-Jurado, L.; Chávez-Alcalá, J.F., E-mail: fchaveza@hotmail.com

    2014-12-05

    Highlights: • pH has an effect on the degradation process of the hybrid materials. • Weight loss depends on the change of pH during the degradation process. • Bioactivity in the materials is strongly related to calcium and pH. - Abstract: In this work, hybrids with great application as bioactive materials having different compositions based on siloxane network were prepared. In vitro bioactivity and in vitro degradability tests were carried out in the materials by soaking them into simulated body fluid (SBF) and into phosphate buffer solution (PBS) to prove their apatite-forming ability and to show their degradation process, respectively. In both in vitro tests, measurements of pH and loss weight were made to observe bioactivity and degradation processes. To prove growth of HA, the materials were characterized through X-ray diffraction, infrared spectroscopy, and scanning electron microscopy. The results showed that some samples have better bioactivity than others. It was found that the incorporation of CaO component into the network of the materials results in an increase of the apatite-forming ability in SBF. Moreover, during the degradation tests, all the samples presented weight loss, especially the ones that contain CaO.

  16. Transport and degradation of metalaxyl and isoproturon in biopurification columns inoculated with pesticide-primed material.

    Science.gov (United States)

    De Wilde, Tineke; Spanoghe, Pieter; Sniegowksi, Kristel; Ryckeboer, Jaak; Jaeken, Peter; Springael, Dirk

    2010-01-01

    Laboratory column displacement experiments were performed to examine whether addition of pesticide-primed material to the matrix of an on-farm biopurification system (BPS), intended to remove pesticides from agricultural waste water, positively affects the degradation of mobile pesticides in the system. Percolated column microcosms with varying types and amounts of metalaxyl and/or isoproturon-primed material or non-primed material were irrigated with water artificially contaminated with isoproturon and/or metalaxyl. Transport of isoproturon was well described using the convection dispersion equation and no dissipation was observed, even in columns inoculated with isoproturon-primed material. On the other hand, delayed dissipation of metalaxyl, i.e., after an initial lag phase, was encountered in all columns receiving metalaxyl. In all systems, dissipation could be described using the Monod model indicating that a metalaxyl degrading population grew in the systems. There was a clear correlation between the lag phase and the amount of metalaxyl-primed material added to the system, i.e., increasing amounts of added material resulted into shorter lag phases and hence more rapid initiation of growth-associated metalaxyl degradation in the system. Our observations suggest that indeed pesticide-primed material can reduce the start-up phase of degradation of mobile pesticides in a BPS and as such can increase its efficiency. However, the primed material should be chosen carefully and preferentially beforehand tested for its capacity to degrade the pesticide.

  17. Heating Process of Thermosetting Insulation Materials for Buildings

    Institute of Scientific and Technical Information of China (English)

    SUN Shibing; MA Baoguo; CHEN Meng; WANG Zhaojun

    2012-01-01

    Polyurethane (PU) and phenolic (PF) foams used for building isolation were analyzed by thermal gravity/differential thermal analysis to determine their pyrolysis behavior,including the decomposition point and the maximum reaction rate point.Besides,the shape deformations of PU and PF foams were observed,and their oxygen index and the calorific value in combustion were also studied.The results showed that the pyrolysis of both PU and PF can be divided into three stages from room temperature to 1 000 ℃ in the atmospheric air,with total mass loss of 94.345% for PF and 88.191% for PU,respectively.The oxygen index of PU and PF decreased with increasing the temperature and the duration of the heat treatment.With the temperature increasing,the calorific values of both materials were reduced remarkably.These results of the PU and PF could provide basic data of the thermal stability and fire safety design in the application of thermosetting insulation materials.

  18. Analytical and Experimental Studies of the Degradation in Hydrogenated Amorphous Silicon Solar Cells and Materials.

    Science.gov (United States)

    Yeung, Ping Fai

    1995-01-01

    An improved understanding of a-Si:H pin solar cells stability was obtained by studying light induced degradation in a-Si:H films and in devices. The current -voltage characteristics and the quantum efficiencies of a-Si:H pin solar cells were measured as a function of intrinsic layer thickness, bias light intensity and degradation condition. Photoconductivity measurements on device quality intrinsic a-Si:H thin film materials showed that the majority carrier (electron) mutau product degraded from 3times 10^{-7}rm cm ^2/V to 2times 10^{ -7}rm cm^2/V after 6 minutes of 50-Suns light illumination. Using a dual beam technique with steady white light and modulated monochromatic light, a degradation profile was detected in the degraded materials. These results suggest that inhomogeneous degradation may be important to understanding the stability of a-Si:H pin solar cells. An analytical model was developed for degradation in a-Si:H pin solar cells based on inhomogeneous degradation, which was used to explain the 'blue-dip' effect observed in the quantum efficiencies of degraded cells. A new method was developed to investigate the minority carrier (hole) diffusion length in device quality a-Si:H films as a function of degradation. This method uses the Schottky barrier structure to establish a depletion region, which can be controlled by the applied voltage and the bias light intensity. Modulated blue light is used to generate electron hole pairs near the ohmic contacts, and the holes diffuse across the neutral region to be collected. The modulated current is related to the diffusion length of the holes due to this current limiting hole transport. Comparing the results of this new technique to that of the Photocarrier Grating method, the electron drift mobility was found to degrade from rm 2.5cm^2/Vs to rm 0.15cm^2/Vs after 6 minutes of 50-Suns degradation.

  19. Quantitative analysis of pulse thermography data for degradation assessment of historical buildings

    Science.gov (United States)

    Di Maio, Rosa; Piegari, Ester; Mancini, Cecilia; Chiapparino, Antonella

    2015-06-01

    In the last decades, infrared thermography has been successfully applied to various materials and structures for the assessment of their state of conservation and planning suitable restoration works. To this aim, mathematical models are required to characterize thermal anomaly sources, such as detachments, water infiltration and material decomposition processes. In this paper, an algorithm based on the conservative finite difference method is used to analyse pulse thermography data acquired on an ancient building in the Pompeii archaeological site (Naples, Italy). The numerical study is applied to both broad and narrow elongated thermal anomalies. In particular, from the comparison between simulated and experimental thermal decays, the plaster thickness was characterized in terms of thermal properties and areas of possible future detachments, and moisture infiltration depths were identified.

  20. Long-Term Lunar Radiation Degradation Effects on Materials

    Science.gov (United States)

    Rojdev, Kristina; ORourke, Mary Jane; Koontz, Steve; Alred, John; Hill, Charles; Devivar, Rodrigo; Morera-Felix, Shakira; Atwell, William; Nutt, Steve; Sabbann, Leslie

    2010-01-01

    The National Aeronautics and Space Administration (NASA) is focused on developing technologies for extending human presence beyond low Earth orbit. These technologies are to advance the state-of-the-art and provide for longer duration missions outside the protection of Earth's magnetosphere. One technology of great interest for large structures is advanced composite materials, due to their weight and cost savings, enhanced radiation protection for the crew, and potential for performance improvements when compared with existing metals. However, these materials have not been characterized for the interplanetary space environment, and particularly the effects of high energy radiation, which is known to cause damage to polymeric materials. Therefore, a study focusing on a lunar habitation element was undertaken to investigate the integrity of potential structural composite materials after exposure to a long-term lunar radiation environment. An overview of the study results are presented, along with a discussion of recommended future work.

  1. Old and Modern Construction Materials In Yemen: The Effect In Building Construction In Sana'a

    Directory of Open Access Journals (Sweden)

    ISSA A.M. Al_Kahtani

    2007-01-01

    Full Text Available Sana’a city in Yemen is one of the oldest cities in the worlds, which has different forms of building built with different types of materials. In the present work, the old and new forms of building construction and the building materials used in Sana’a, the sources available for the new material, the effects of new material usage on building forms are all presented with the advantages and disadvantages of each material. The old shapes of buildings in Yemen and the classical and modern forms of construction using different types of materials are considered in the study. Survey is used to investigate the building forms and material types in Sana’a. Several conclusions are submitted showing that, the new building material, such as concrete block, is preferred in building comparing with old material, such as stone, which makes it the best choice for the low income people but sometimes the limited resources make old material the only available choice. Several steps needed to develop and encourage the use of new building materials are recommended.

  2. Infrared Emissivity Measurements for Mineral Materials and Materials Used for Infrastructure Building

    Science.gov (United States)

    Monchau, Jean-Pierre; Ibos, Laurent; Marchetti, Mario; Dumoulin, Jean; Feuillet, Vincent; Candau, Yves; Ausset, Patrick

    2013-04-01

    The knowledge of the infrared emissivity of materials used in buildings, civil engineering structures and soils studies is useful for two specific approaches. Firstly, quantitative diagnosis of buildings or civil engineering infrastructures using infrared thermography requires the emissivity value of materials in the spectral bandwidth of the camera. For instance emissivity in the band III domain is required when using cameras with uncooled detectors like micro-bolometers arrays. The knowledge of emissivity is in that case needed for computation of surface temperature fields. Secondly, accurate thermal balance requires the emissivity value in a large wavelength domain. This is for instance the case for computing roads surface temperature to predict ice forming. A measurement of emissivity just after construction and a regular survey of its variations due to ageing or soiling of surfaces could be useful in many situations like thermal mapping of roads or building insulation diagnosis. For mineral materials, a lot of studies exist, but often in situ value of emissivity could be different. Mineral materials are not pure, and could be soiled. Real value obtained with a field device is required. The use of portable emissivity measurement devices is required for that purpose. Thus, two devices using the indirect measurement method were developed. The emissivity value is deduced from the measurement of the reflectivity of the material under study after calibration with a highly reflective surface. The first device uses a slow modulation frequency well adapted to laboratory measurements whereas the second one is a portable system using a faster modulation frequency authorizing outdoor measurements. Both devices allow measurements in broad band (1 to 40μm) and band III (8 to 14μm). Experiments were performed on a large number of materials commonly used in buildings and civil engineering structures. For instance at that time 180 samples of different pavement wearing course

  3. TiO2-based building materials: Above and beyond traditional applications

    Institute of Scientific and Technical Information of China (English)

    GUO Sen; WU ZhongBiao; ZHAO WeiRong

    2009-01-01

    In the 1910s, TiO2 began to be used in building materials as pigments and opacifier due to its excellent optical property. Since the photocatalytic property of TiO2 was observed in 1972, its application field was expanded to air cleaning and sterilization. Thereafter, people added TiO2 into building materials to develop novel and facile building materials. These materials were widely used for air cleaning, sterili-zation, self-cleaning, anti-fogging, decoration, and building cooling. The combination of building and other functions can serve simultaneously. Although TiO2-based building materials have bright pros-pects, some aspects such as improving the stability and enhancing photoactive performance of the materials are of importance for future research.

  4. The effect of using low-polluting building materials on ventilation requirements and energy use in buildings

    Energy Technology Data Exchange (ETDEWEB)

    Wargocki, P.; Frontczak, M. (International Centre for Indoor Environment and Energy, Dept. of Mechanical Engineering, DTU, Kgs. Lyngby (DK)); Knudsen, Henrik N. (Danish Building Research Institute, Aalborg Univ., Hoersholm (DK))

    2007-07-01

    The main objective of the ongoing research project described in this paper was to study the potential for reducing energy used for ventilating buildings by using low-polluting building materials, without compromising the indoor air quality. To quantify this potential, the exposure-response relationships, i.e. the relationships between ventilation rate and perceived indoor air quality, were established for rooms furnished with different categories of polluting materials and the simulations of energy used for ventilation were carried out. The exposure-response relationships were based on a summary of data reported in the literature on exposure-response relationships for materials tested in laboratory settings in small-scale glass chambers, and in full-scale in climate chambers, test rooms or normal offices. New experiments were also considered in which the effect of using low-polluting materials on perceived air quality was examined in test rooms ventilated with different outdoor air supply rates, low-polluting materials being selected in small glass chambers. The results suggest that the exposure-response relationships vary between different building materials and that the perceived air quality can be improved considerably when polluting building materials are substituted with materials that pollute less. The preliminary energy simulations indicate that selecting low-polluting materials will result in considerable energy savings as a result of reducing the ventilation rates required to achieve acceptable indoor air quality. (au)

  5. Weld repair of helium degraded reactor vessel material

    Energy Technology Data Exchange (ETDEWEB)

    Kanne, W.R. Jr.; Lohmeier, D.A.; Louthan, M.R. Jr.; Rankin, D.T.; Franco-Ferreira, E.A. (Westinghouse Savannah River Co., Aiken, SC (United States)); Bruck, G.J.; Madeyski, A.; Shogan, R.P.; Lessmann, G.G. (Westinghouse Electric Corp., Pittsburgh, PA (United States). Science and Technology Center)

    1990-01-01

    Welding methods for modification or repair of irradiated nuclear reactor vessels are being evaluated at the Savannah River Site. A low-penetration weld overlay technique has been developed to minimize the adverse effects of irradiation induced helium on the weldability of metals and alloys. This technique was successfully applied to Type 304 stainless steel test plates that contained 3 to 220 appm helium from tritium decay. Conventional welding practices caused significant cracking and degradation in the test plates. Optical microscopy of weld surfaces and cross sections showed that large surface toe cracks formed around conventional welds in the test plates but did not form around overlay welds. Scattered incipient underbead cracks (grain boundary separations) were associated with both conventional and overlay test welds. Tensile and bend tests were used to assess the effect of base metal helium content on the mechanical integrity of the low-penetration overlay welds. The axis of tensile specimens was perpendicular to the weld-base metal interface. Tensile specimens were machined after studs were resistance welded to overlay surfaces.

  6. Weld repair of helium degraded reactor vessel material

    Energy Technology Data Exchange (ETDEWEB)

    Kanne, W.R. Jr.; Lohmeier, D.A.; Louthan, M.R. Jr.; Rankin, D.T.; Franco-Ferreira, E.A. [Westinghouse Savannah River Co., Aiken, SC (United States); Bruck, G.J.; Madeyski, A.; Shogan, R.P.; Lessmann, G.G. [Westinghouse Electric Corp., Pittsburgh, PA (United States). Science and Technology Center

    1990-12-31

    Welding methods for modification or repair of irradiated nuclear reactor vessels are being evaluated at the Savannah River Site. A low-penetration weld overlay technique has been developed to minimize the adverse effects of irradiation induced helium on the weldability of metals and alloys. This technique was successfully applied to Type 304 stainless steel test plates that contained 3 to 220 appm helium from tritium decay. Conventional welding practices caused significant cracking and degradation in the test plates. Optical microscopy of weld surfaces and cross sections showed that large surface toe cracks formed around conventional welds in the test plates but did not form around overlay welds. Scattered incipient underbead cracks (grain boundary separations) were associated with both conventional and overlay test welds. Tensile and bend tests were used to assess the effect of base metal helium content on the mechanical integrity of the low-penetration overlay welds. The axis of tensile specimens was perpendicular to the weld-base metal interface. Tensile specimens were machined after studs were resistance welded to overlay surfaces.

  7. Immobilization of fungal laccase onto a nonionic surfactant-modified clay material: application to PAH degradation.

    Science.gov (United States)

    Chang, Yi-Tang; Lee, Jiunn-Fwu; Liu, Keng-Hua; Liao, Yi-Fen; Yang, Vivian

    2016-03-01

    Nonionic surfactant-modified clay is a useful absorbent material that effectively removes hydrophobic organic compounds from soil/groundwater. We developed a novel material by applying an immobilized fungal laccase onto nonionic surfactant-modified clay. Low-water-solubility polycyclic aromatic hydrocarbons (PAHs) (naphthalene/phenanthrene) were degraded in the presence of this bioactive material. PAH degradation by free laccase was higher than degradation by immobilized laccase when the surfactant concentration was allowed to form micelles. PAH degradation by immobilized laccase on TX-100-modified clay was higher than on Brij35-modified clay. Strong laccase degradation of PAH can be maintained by adding surfactant monomers or micelles. The physical adsorption of nonionic surfactants onto clay plays an important role in PAH degradation by laccase, which can be explained by the structure and molecular interactions of the surfactant with the clay and enzyme. A system where laccase is immobilized onto TX-100-monomer-modified clay is a good candidate bioactive material for in situ PAHs bioremediation.

  8. Thermal analysis of a building brick containing phase change material

    Energy Technology Data Exchange (ETDEWEB)

    Alawadhi, E.M. [Kuwait Univ., Safat (Kuwait). Dept. of Mechanical Engineering

    2008-07-01

    This paper presents the thermal analysis of a building brick containing phase change material (PCM) to be used in hot climates. The objective of using the PCM is to utilize its high latent heat of fusion to reduce the heat gain by absorbing the heat in the bricks through the melting process before it reaches the indoor space. The considered model consists of bricks with cylindrical holes filled with PCM. The problem is solved in a two-dimensional space using the finite element method. The thermal effectiveness of the proposed brick-PCM system is evaluated by comparing the heat flux at the indoor surface to a wall without the PCM during typical working hours. A paramedic study is conducted to assess the effect of different design parameters, such as the PCM's quantity, type, and location in the brick. The results indicate that the heat gain is significantly reduced when the PCM is incorporated into the brick, and increasing the quantity of the PCM has a positive effect. PCM cylinders located at the centerline of the bricks shows the best performance. (author)

  9. Prediction of Long Term Degradation of Insulating Materials

    Science.gov (United States)

    2015-05-01

    carbon dioxide and sulfur dioxide (recognized elements in acid rain) by reducing demand for fossil fuels (thermal insulation materials). However...Strategies to reduce air infiltration, include weather stripping , weather sealing tapes, and housewrap. Further consideration of air infiltration is...of ASTM Standards 04.06:173- 184. Acoustiblok Inc. 2009. Thermablok Thermal Acoustic Isolation Strips . Safety Data Sheet, http://www.thermablok.com

  10. Fire Safety Aspects of Polymeric Materials. Volume 7. Buildings

    Science.gov (United States)

    1979-01-01

    Custodial Buildings 136 4.5.5 Retail Stores, Malls, etc. 138 l’ 4.5.6 Restaurants and Nightclubs 4.5.7 Public Assembly Occupancies - Auditoria , Theaters... auditoria , theaters, exhibition halls, arenas, transportation terminals; educational buildings and indus- trial buildings. Many of the fire safety...usage are developed. 4.5.7 Public Assembly Occupancies - Auditoria , Theaters, Exhibition Halls, Arenas, Transportation Terminals, Etc. The factors

  11. A mass transfer model for predicting emission of the volatile organic compounds in wet building materials

    Institute of Scientific and Technical Information of China (English)

    ZHANG Tao; JIA Li

    2008-01-01

    A new mass transfer model is developped to predict the volatile organic compounds (VOCs) from fresh wet building materials. The dry section of wet materials during the process of VOC emission from wet building materials is considered in this new model, differing from the mass transfer-based models in other literatures. The mechanism of effect of saturated vapor pressure on the surface of wet building materials in the process of VOC emission is discussed. The concentration of total volatile organic compounds (TVOC) in the building materials gradually decreases as the emission of VOCs begins, and the vapor pressure of VOCs on the surface of wet building materials decreases in the case of newly wet building materials. To ensure the partial pressure of VOCs on the surface of wet building materials to be saturated vapor pressure, the interface of gas-wet layer is lowered, and a dry layer of no-volatile gases in the material is formed. Compared with the results obtained by VB model, CFD model and the ex-periment data, the results obtained by the present model agree well with the results obtained by CFD model and the experiment data. The present model is more accurate in predicting emission of VOC from wet building materials than VB model.

  12. Substrate-anchored and degradation-sensitive anti-inflammatory coatings for implant materials

    Science.gov (United States)

    Wu, Duo; Chen, Xingyu; Chen, Tianchan; Ding, Chunmei; Wu, Wei; Li, Jianshu

    2015-06-01

    Implant materials need to be highly biocompatible to avoid inflammation in clinical practice. Although biodegradable polymeric implants can eliminate the need for a second surgical intervention to remove the implant materials, they may produce acidic degradation products in vivo and cause non-bacterial inflammation. Here we show the strategy of “substrate-anchored and degradation-sensitive coatings” for biodegradable implants. Using poly(lactic acid)/hydroxyapatite as an implant material model, we constructed a layer-by-layer coating using pH-sensitive star polymers and dendrimers loaded with an anti-inflammatory drug, which was immobilised through a hydroxyapatite-anchored layer. The multifunctional coating can effectively suppress the local inflammation caused by the degradation of implant materials for at least 8 weeks in vivo. Moreover, the substrate-anchored coating is able to modulate the degradation of the substrate in a more homogeneous manner. The “substrate-anchored and degradation-sensitive coating” strategy therefore exhibits potential for the design of various self-anti-inflammatory biodegradable implant materials.

  13. Measurements and simulations of boron carbide as degrader material for proton therapy

    Science.gov (United States)

    Gerbershagen, Alexander; Baumgarten, Christian; Kiselev, Daniela; van der Meer, Robert; Risters, Yannic; Schippers, Marco

    2016-07-01

    We report on test measurements using boron carbide (B4C) as degrader material in comparison with the conventional graphite, which is currently used in many proton therapy degraders. Boron carbide is a material of lower average atomic weight and higher density than graphite. Calculations predict that, compared to graphite, the use of boron carbide results in a lower emittance behind the degrader due to the shorter degrader length. Downstream of the acceptance defining collimation system we expect a higher beam transmission, especially at low beam energies. This is of great interest in proton therapy applications as it allows either a reduction of the beam intensity extracted from the cyclotron leading to lower activation or a reduction of the treatment time. This paper summarizes the results of simulations and experiments carried out at the PROSCAN facility at the Paul Scherrer Institute1. The simulations predict an increase in the transmitted beam current after the collimation system of approx. 30.5% for beam degradation from 250 to 84 MeV for a boron carbide degrader compared to graphite. The experiment carried out with a boron carbide block reducing the energy to 84 MeV yielded a transmission improvement of 37% compared with the graphite degrader set to that energy.

  14. Measurements and simulations of boron carbide as degrader material for proton therapy.

    Science.gov (United States)

    Gerbershagen, Alexander; Baumgarten, Christian; Kiselev, Daniela; van der Meer, Robert; Risters, Yannic; Schippers, Marco

    2016-07-21

    We report on test measurements using boron carbide (B4C) as degrader material in comparison with the conventional graphite, which is currently used in many proton therapy degraders. Boron carbide is a material of lower average atomic weight and higher density than graphite. Calculations predict that, compared to graphite, the use of boron carbide results in a lower emittance behind the degrader due to the shorter degrader length. Downstream of the acceptance defining collimation system we expect a higher beam transmission, especially at low beam energies. This is of great interest in proton therapy applications as it allows either a reduction of the beam intensity extracted from the cyclotron leading to lower activation or a reduction of the treatment time. This paper summarizes the results of simulations and experiments carried out at the PROSCAN facility at the Paul Scherrer Institute(1). The simulations predict an increase in the transmitted beam current after the collimation system of approx. 30.5% for beam degradation from 250 to 84 MeV for a boron carbide degrader compared to graphite. The experiment carried out with a boron carbide block reducing the energy to 84 MeV yielded a transmission improvement of 37% compared with the graphite degrader set to that energy.

  15. An overview of materials degradation by stress corrosion in PWRs

    Energy Technology Data Exchange (ETDEWEB)

    Scott, P. M. [Framatome ANP, Tour Areva, 92084 Paris La Defense Cedex (France)

    2004-07-01

    The aging of water cooled and moderated nuclear steam supply systems has given rise to many material corrosion problems of which stress corrosion cracking has proved to be one of the most serious. The aim of this paper is to review some examples of corrosion and particularly stress corrosion problems from the author's experience of interpreting and modelling these phenomena in PWR systems. Examples of stress corrosion cracking in PWR systems described include the major issue of Alloy 600 intergranular cracking in primary PWR coolants, for which it is generally perceived that both adequate life prediction models and remedial measures now exist. Intergranular corrosion and stress corrosion cracking of Alloy 600 steam generator tubes that occur in occluded superheated crevices on the secondary side of steam generators due to hide-out and concentration of water borne impurities are also addressed. Rather less extensive or well known examples are discussed such as the stress corrosion cracking of carbon and low alloy steels and of stainless steels in occluded dead-leg situations where it is sometimes difficult to guarantee adequate control of water chemistry, particularly at plant start-up. Reference is also be made to the use of high strength fastener materials in PWR systems as well as to the emerging issue of the effect of high neutron doses on the stress corrosion resistance of core structural components fabricated from austenitic stainless steels. (authors)

  16. Synthesis and degradation properties of -TCP/BG porous composite materials

    Indian Academy of Sciences (India)

    Fan Xin; Chen Jian; Ruan Jianming; Zhou Zhongcheng; Zou Jianpeng

    2011-04-01

    -TCP/BG porous composite materials were successfully fabricated by foaming technology. X-ray diffraction was used to determine the crystal structure of powders. The pore size and distribution of the resulting materials were characterized using scanning electron microscopy. The porosity and degradation performance of materials were also investigated. The results showed that the porous composite materials possessed the pore size ranging from 100 to 500 m in diameter, whereas the interconnection among macrospores was poor. The porosity in materials increased from 58.7% to 63.47% with BG content ranging from 0 to 3 wt%, further increasing of BG content results in a decrease in porosity. The degradation rate of composite materials can be adjusted by varying the BG content.

  17. Development of biodegradable materials; balancing degradability and performance

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, J.M.; Allen, A.L.; Dell, P.A.; McCassie, J.E.; Shupe, A.E.; Stenhouse, P.J. Stenhouse, Welch, E.A.; Kaplan, D.L. [Army Natick Research Development, MA (United States)

    1993-12-31

    The development of biodegradable materials suitable for packaging must take into consideration various performance criteria such as mechanical and barrier properties, as well as rate of biodegradability in given environments. Individual or blended biopolymer films were obtained commercially or blown into film in the laboratory and tested for tensile strength, ultimate elongation and oxygen barrier. These films were then subjected to accelerated marine biodegradation tests as well as simulated marine respirometry. Starch/ethylene vinyl alcohol films exhibited good mechanical and excellent oxygen barrier properties, but were very slow to biodegrade in the simulated and excellent oxygen barrier properties, but were very slow to biodegrade in the simulated marine environment. Polyhydroxyalkanoates had good mechanical properties, average oxygen barrier and good biodegradability. Data indicate that performance and biodegradability of packaging can be tailored to needs by combining individual biopolymers in different proportions in blends and laminates.

  18. Degradation of thermal control materials under a simulated radiative space environment

    Science.gov (United States)

    Sharma, A. K.; Sridhara, N.

    2012-11-01

    A spacecraft with a passive thermal control system utilizes various thermal control materials to maintain temperatures within safe operating limits. Materials used for spacecraft applications are exposed to harsh space environments such as ultraviolet (UV) and particle (electron, proton) irradiation and atomic oxygen (AO), undergo physical damage and thermal degradation, which must be considered for spacecraft thermal design optimization and cost effectiveness. This paper describes the effect of synergistic radiation on some of the important thermal control materials to verify the assumptions of beginning-of-life (BOL) and end-of-life (EOL) properties. Studies on the degradation in the optical properties (solar absorptance and infrared emittance) of some important thermal control materials exposed to simulated radiative geostationary space environment are discussed. The current studies are purely related to the influence of radiation on the degradation of the materials; other environmental aspects (e.g., thermal cycling) are not discussed. The thermal control materials investigated herein include different kind of second-surface mirrors, white anodizing, white paints, black paints, multilayer insulation materials, varnish coated aluminized polyimide, germanium coated polyimide, polyether ether ketone (PEEK) and poly tetra fluoro ethylene (PTFE). For this purpose, a test in the constant vacuum was performed reproducing a three year radiative space environment exposure, including ultraviolet and charged particle effects on North/South panels of a geostationary three-axis stabilized spacecraft. Reflectance spectra were measured in situ in the solar range (250-2500 nm) and the corresponding solar absorptance values were calculated. The test methodology and the degradations of the materials are discussed. The most important degradations among the low solar absorptance materials were found in the white paints whereas the rigid optical solar reflectors remained quite

  19. Radon diffusion studies in some building materials using solid state nuclear track detectors

    CERN Document Server

    Singh, S; Singh, B; Singh, J

    1999-01-01

    LR-115 plastic track detector has been used to study radon diffusion through some building materials, viz. cement, soil, marble chips, sand and lime as well as air. Diffusion constant and diffusion length is calculated for all these materials.

  20. Determination of fungal spore release from wet building materials.

    Science.gov (United States)

    Kildesø, J; Würtz, H; Nielsen, K F; Kruse, P; Wilkins, K; Thrane, U; Gravesen, S; Nielsen, P A; Schneider, T

    2003-06-01

    The release and transport of fungal spores from water-damaged building materials is a key factor for understanding the exposure to particles of fungal origin as a possible cause of adverse health effects associated to growth of fungi indoors. In this study, the release of spores from nine species of typical indoor fungi has been measured under controlled conditions. The fungi were cultivated for a period of 4-6 weeks on sterilized wet wallpapered gypsum boards at a relative humidity (RH) of approximately 97%. A specially designed small chamber (P-FLEC) was placed on the gypsum board. The release of fungal spores was induced by well-defined jets of air impacting from rotating nozzles. The spores and other particles released from the surface were transported by the air flowing from the chamber through a top outlet to a particle counter and sizer. For two of the fungi (Penicillium chrysogenum and Trichoderma harzianum), the number of spores produced on the gypsum board and subsequently released was quantified. Also the relationship between air velocities from 0.3 to 3 m/s over the surface and spore release has been measured. The method was found to give very reproducible results for each fungal isolate, whereas the spore release is very different for different fungi under identical conditions. Also, the relationship between air velocity and spore release depends on the fungus. For some fungi a significant number of particles smaller than the spore size were released. The method applied in the study may also be useful for field studies and for generation of spores for exposure studies.

  1. Natural radioactivity measurements in building materials in Southern Lebanon.

    Science.gov (United States)

    Kobeissi, M A; El Samad, O; Zahraman, K; Milky, S; Bahsoun, F; Abumurad, K M

    2008-08-01

    Using gamma-spectroscopy and CR-39 detector, concentration C of naturally occurring radioactive nuclides (226)Ra, (222)Rn, (214)Bi, (228)Ac, (212)Pb, (212)Bi and (40)K, has been measured in sand, cement, gravel, gypsum, and paint, which are used as building materials in Lebanon. Sand samples were collected from 10 different sandbank locations in the southern part of the country. Gravel samples of different types and forms were collected from several quarries. White and gray cement fabricated by Shaka Co. were obtained. gamma-spectroscopy measurements in sand gave Ra concentration ranging from 4.2+/-0.4 to 60.8+/-2.2 Bq kg(-1) and Ra concentration equivalents from 8.8+/-1.0 to 74.3+/-9.2 Bq kg(-1). The highest Ra concentration was in gray and white cement having the values 73.2+/-3.0 and 76.3+/-3.0 Bq kg(-1), respectively. Gravel results showed Ra concentration between 20.2+/-1.0 and 31.7+/-1.4 Bq kg(-1) with an average of 27.5+/-1.3 Bq kg(-1). Radon concentration in paint was determined by CR-39 detector. In sand, the average (222)Rn concentration ranged between 291+/-69 and 1774+/-339 Bq m(-3) among the sandbanks with a total average value of 704+/-139 Bq m(-3). For gravel, the range was found to be from 52+/-9 to 3077+/-370 Bq m(-3) with an average value of 608+/-85 Bq m(-3). Aerial and mass exhalation rates of (222)Rn were also calculated and found to be between 44+/-7 and 2226+/-267 mBq m(-2)h(-1), and between 0.40+/-0.07 and 20.0+/-0.3 mBq kg(-1)h(-1), respectively.

  2. Study on characteristics of double surface VOC emissions from dry flat-plate building materials

    Institute of Scientific and Technical Information of China (English)

    WANG Xinke; ZHANG Yinping; ZHAO Rongyi

    2006-01-01

    This paper sets up an analytic model of double surface emission of volatile organic compound (VOC) from dry, flat-plate building materials. Based on it, the influence of factors including air change rate, loading factor of materials in the room, mass diffusion coefficient, partition coefficient, convective mass transfer coefficient, thickness of materials, asymmetric convective flow and initial VOC concentration distribution in the building material on emission is discussed. The conditions for simplifying double surface emission into single surface emission are also discussed. The model is helpful to assess the double surface VOC emission from flat-plate building materials used in indoor furniture and space partition.

  3. Alternative materials for desert buildings: a comparative life cycle energy analysis

    Energy Technology Data Exchange (ETDEWEB)

    Pearlmutter, D.; Freidin, C.; Huberman, N. [Institutes for Desert Research, Ben-Gurion University of the Negev, (Israel)

    2007-03-15

    This study examines the potential life-cycle energy savings that may be achieved by combining an innovative alternative building material and a bioclimatic approach to building design under the distinctive environmental conditions of a desert region. A residential building in the Negev region of Israel is used as a model for the assessment. Designed with a number of climatically-responsive design strategies and conventional concrete-based materials, the building was energy-independent in terms of summer cooling and had only modest requirements for winter heating. As a second step to the assessment, the integration of an alternative building material based on industrial waste and local raw materials in the building's walls was considered through thermal simulation. The alternative materials are produced through a process developed to make productive utilization of fly-ash from oil shale and coal combustion. Material properties were analyzed using laboratory specimens, and it was established that high-quality building components could be produced using the developed technological procedure with standard manufacturing equipment. The consumption of both embodied and operational energy was analyzed over the building's useful life span, and this life-cycle analysis showed the clear advantage of integrating alternative materials in a building under environmental conditions in a desert environment. (Author)

  4. Material degradation due to moisture and temperature. Part 1: mathematical model, analysis, and analytical solutions

    Science.gov (United States)

    Xu, C.; Mudunuru, M. K.; Nakshatrala, K. B.

    2016-11-01

    The mechanical response, serviceability, and load-bearing capacity of materials and structural components can be adversely affected due to external stimuli, which include exposure to a corrosive chemical species, high temperatures, temperature fluctuations (i.e., freezing-thawing), cyclic mechanical loading, just to name a few. It is, therefore, of paramount importance in several branches of engineering—ranging from aerospace engineering, civil engineering to biomedical engineering—to have a fundamental understanding of degradation of materials, as the materials in these applications are often subjected to adverse environments. As a result of recent advancements in material science, new materials such as fiber-reinforced polymers and multi-functional materials that exhibit high ductility have been developed and widely used, for example, as infrastructural materials or in medical devices (e.g., stents). The traditional small-strain approaches of modeling these materials will not be adequate. In this paper, we study degradation of materials due to an exposure to chemical species and temperature under large strain and large deformations. In the first part of our research work, we present a consistent mathematical model with firm thermodynamic underpinning. We then obtain semi-analytical solutions of several canonical problems to illustrate the nature of the quasi-static and unsteady behaviors of degrading hyperelastic solids.

  5. Controlling Beryllium Contaminated Material And Equipment For The Building 9201-5 Legacy Material Disposition Project

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, T. D.; Easterling, S. D.

    2010-10-01

    This position paper addresses the management of beryllium contamination on legacy waste. The goal of the beryllium management program is to protect human health and the environment by preventing the release of beryllium through controlling surface contamination. Studies have shown by controlling beryllium surface contamination, potential airborne contamination is reduced or eliminated. Although there are areas in Building 9201-5 that are contaminated with radioactive materials and mercury, only beryllium contamination is addressed in this management plan. The overall goal of this initiative is the compliant packaging and disposal of beryllium waste from the 9201-5 Legacy Material Removal (LMR) Project to ensure that beryllium surface contamination and any potential airborne release of beryllium is controlled to levels as low as practicable in accordance with 10 CFR 850.25.

  6. The contribute of using vernacular materials and techniques for sustainable building

    OpenAIRE

    Fernandes, Jorge Emanuel Pereira; Mateus, Ricardo; Bragança, L.

    2013-01-01

    The use of local materials and techniques is one of the main features from vernacular architecture. When compared with industrially-produced materials, vernacular materials have low environmental impacts, being an alternative for sustainable building. However, industrialization have brought new standardized materials that led to the homogenization of the different building approaches and spawned a universal architecture often with no context concerns and with significant environmental i...

  7. Development of materials resistant to metal dusting degradation.

    Energy Technology Data Exchange (ETDEWEB)

    Natesan, K.; Zeng, Z.

    2006-04-24

    Metal dusting corrosion has been a serious problem in the petroleum and petrochemical industries, such as reforming and syngas production systems. This form of deterioration has led to worldwide material loss for 50 years. For the past three years, we have studied the mechanism of metal dusting for Fe- and Ni-base alloys. In this report, we present a correlation between the weight loss and depth of pits that form in Ni-base alloys. Nickel-base alloys were also tested at 1 and 14.8 atm (210 psi), in a high carbon activity environment. Higher system pressure was found to accelerate corrosion in most Ni-base alloys. To reduce testing time, a pre-pitting method was developed. Mechanical scratches on the alloy surface led to fast metal dusting corrosion. We have also developed preliminary data on the performance of weldments of several Ni-base alloys in a metal dusting environment. Finally, Alloy 800 tubes and plates used in a reformer plant were examined by scanning electron microscopy, energy dispersive X-ray, and Raman spectroscopy. The oxide scale on the surface of the Alloy 800 primarily consists of Fe{sub 1+x}Cr{sub 2-X}O{sub 4} spinel phase with high Fe content. Carbon can diffuse through this oxide scale. It was discovered that the growth of metal dusting pits could be stopped by means of a slightly oxidized alloy surface. This leads to a new way to solve metal dusting problem.

  8. Guidelines for Assessment and Abatement of Asbestos-Containing Materials in Buildings.

    Science.gov (United States)

    Pielert, James H.; Mathey, Robert G.

    This report presents guidelines, based on available information, for the assessment and abatement of asbestos-containing materials in buildings. Section 1 provides background information on the history and use of asbestos-containing products in buildings, the characteristics of asbestos fibers, products and materials containing asbestos, and…

  9. Investigation of thermal effect on exterior wall surface of building material at urban city area

    OpenAIRE

    Mohd Fadhil Md Din, Hazlini Dzinun, M. Ponraj, Shreeshivadasan Chelliapan, Zainura Zainun Noor, Dilshah Remaz, Kenzo Iwao

    2012-01-01

    This paper describes the investigation of heat impact on the vertical surfaces of buildings based on their thermal behavior. The study was performed based on four building materials that is commonly used in Malaysia; brick, concrete, granite and white concrete tiles. The thermal performances on the building materials were investigated using a surface temperature sensor, data logging system and infrared thermography. Results showed that the brick had the capability to absorb and store heat gre...

  10. Building Thermal Envelope Systems and Materials (BTESM) and research utilization/technology transfer

    Energy Technology Data Exchange (ETDEWEB)

    Burn, G. (comp.)

    1990-07-01

    The Monthly Report of the Building Thermal Envelope Systems and Materials (BTESM) Programs is a monthly update of both in-house ORNL projects and subcontract activities in the research areas of building materials, wall systems, foundations, roofs, building diagnostics, and research utilization and technology transfer. Presentations are not stand-alone paragraphs every month. Their principal values are the short-time lapse between accomplishment and reporting and their evolution over a period of several months..

  11. Simulated Aging and Characterization of Phase Change Materials for Thermal Management of Building Envelopes

    Science.gov (United States)

    2015-09-01

    Method B). West Conshohocken, PA: ASTM International. ———. 2009. Standard Method for Surface Burning Characteristics of Building Materials. ASTM E84-09...storage in buildings : A state of art. Renewable and Sustainable Energy Reviews 11(6):1146-1166 Yu, S., S. Jeong, C. Chyoung, and S. Kim. 2014. Bio-based...Simulated Aging and Characterization of Phase Change Materials for lhermal Management of Building Envelopes Elizabeth J. Gao, Jignesh Patel, Veera M. Boddu

  12. 15 CFR 270.325 - Notice of authority to enter and inspect property where building components, materials, artifacts...

    Science.gov (United States)

    2010-01-01

    ... inspect property where building components, materials, artifacts, and records with respect to a building... Notice of authority to enter and inspect property where building components, materials, artifacts, and... investigated has occurred, or where building components, materials, and artifacts with respect to the...

  13. Plasma technology for creation of protective and decorative coatings for building materials

    Science.gov (United States)

    Volokitin, Oleg; Volokitin, Gennady; Skripnikova, Nelli; Shekhovtsov, Valentin

    2016-01-01

    An experimental setup is developed to create a protective and decorative coating on the surface of building materials. Experimental study is conducted to create a protective coating using low-temperature plasma. The properties of the surface before and after the plasma treatment are investigated. At the increase of the plasma generator power (56-75 kW) the rate of the vitreous coating formation is significantly reduced, and the destruction of hydrous calcium silicates occurs at a lower depth (0.5-2.0 mm). In this case, the adhesive strength increases up to 2.34 MPa. At the increase of the exposure time at 56 kW (0.045 m/s melting rate) plasma generation power, the melt formation is observed not only at the surface but at depth of 0.7 mm and deeper. Also, a deep degradation of the material occurs and the adhesive strength decreases. The optimal heat flux density of plasma generator was established at 1.8-2.6 . 106 W/m2, which allows the achievement of the uniform layer formation on the wood surface that preserves its natural pattern visible.

  14. HOW DO DEGRADABLE/BIODEGRADABLE PLASTIC MATERIALS DECOMPOSE IN HOME COMPOSTING ENVIRONMENT?

    Directory of Open Access Journals (Sweden)

    Magdalena Vaverková

    2014-10-01

    Full Text Available This paper provides information about biodegradability of polymeric (biodegradable/degradable materials advertised as 100%-degradable or certified as compostable, which may be a part of biodegradable waste, in home composting conditions. It describes an experiment that took place in home wooden compost bins and contained 9 samples that are commonly available in retail chains in the Czech Republic and Poland. The experiment lasted for the period of 12 weeks. Based on the results thereof it can be concluded that polyethylene samples with additive (samples 2, 4, 7 have not decomposed, their color has not changed and that no degradation or physical changes have occurred. Samples 1, 3 and 5 certified as compostable have not decomposed. Sample 6 exhibited the highest decomposition rate. Samples 8, 9 (tableware exhibited high degree of decomposition. The main conclusion from this study is that degradable/biodegradable plastics or plastics certified as compostable are not suitable for home composting.

  15. Natural radioactivity measurements in building materials in Southern Lebanon

    Energy Technology Data Exchange (ETDEWEB)

    Kobeissi, M.A.; El Samad, O.; Zahraman, K. [Lebanese Atomic Energy Commission, National Council for Scientific Research, P.O. Box 11-8281, Beirut (Lebanon); Milky, S.; Bahsoun, F. [Department of Physics, Lebanese University, Faculty of Sciences (I), Hadeth, Beirut (Lebanon); Abumurad, K.M. [Department of Physics, Yarmouk University, P.O. Box 566, Irbid 21163 (Jordan)], E-mail: abumurad@yu.edu.jo

    2008-08-15

    Using {gamma}-spectroscopy and CR-39 detector, concentration C of naturally occurring radioactive nuclides {sup 226}Ra, {sup 222}Rn, {sup 214}Bi, {sup 228}Ac, {sup 212}Pb, {sup 212}Bi and {sup 40}K, has been measured in sand, cement, gravel, gypsum, and paint, which are used as building materials in Lebanon. Sand samples were collected from 10 different sandbank locations in the southern part of the country. Gravel samples of different types and forms were collected from several quarries. White and gray cement fabricated by Shaka Co. were obtained. {gamma}-Spectroscopy measurements in sand gave Ra concentration ranging from 4.2 {+-} 0.4 to 60.8 {+-} 2.2 Bq kg{sup -1} and Ra concentration equivalents from 8.8 {+-} 1.0 to 74.3 {+-} 9.2 Bq kg{sup -1}. The highest Ra concentration was in gray and white cement having the values 73.2 {+-} 3.0 and 76.3 {+-} 3.0 Bq kg{sup -1}, respectively. Gravel results showed Ra concentration between 20.2 {+-} 1.0 and 31.7 {+-} 1.4 Bq kg{sup -1} with an average of 27.5 {+-} 1.3 Bq kg{sup -1}. Radon concentration in paint was determined by CR-39 detector. In sand, the average {sup 222}Rn concentration ranged between 291 {+-} 69 and 1774 {+-} 339 Bq m{sup -3} among the sandbanks with a total average value of 704 {+-} 139 Bq m{sup -3}. For gravel, the range was found to be from 52 {+-} 9 to 3077 {+-} 370 Bq m{sup -3} with an average value of 608 {+-} 85 Bq m{sup -3}. Aerial and mass exhalation rates of {sup 222}Rn were also calculated and found to be between 44 {+-} 7 and 2226 {+-} 267 mBq m{sup -2} h{sup -1}, and between 0.40 {+-} 0.07 and 20.0 {+-} 0.3 mBq kg{sup -1} h{sup -1}, respectively.

  16. Smart Materials For The Realization Of An Adaptive Building Component

    NARCIS (Netherlands)

    Lelieveld, C.M.J.L.

    2013-01-01

    This research focusses on the realization of adaptive architecture with the use of advanced material technology. Current material research has shown significant advances with the development of “smart” materials. Smart materials are “capable of automatically and inherently sensing or detecting chang

  17. Recommendations for Exploring the Disfluency Hypothesis for Establishing Whether Perceptually Degrading Materials Impacts Performance

    Science.gov (United States)

    Dunlosky, John; Mueller, Michael L.

    2016-01-01

    The target articles explore a common hypothesis pertaining to whether perceptually degrading materials will improve reasoning, memory, and metamemory. Outcomes are mixed, yet some evidence was garnered in support of a version of the disfluency hypothesis that includes moderators, and along with evidence from prior research, researchers will likely…

  18. SCAPS Modeling for Degradation of Ultrathin CdTe Films: Materials Interdiffusion

    Science.gov (United States)

    Houshmand, Mohammad; Zandi, M. Hossein; Gorji, Nima E.

    2015-09-01

    Ultrathin film solar cells based on CdS/CdTe ( d CdTe ≤ 1 µm) suffer from two main issues: incomplete photo absorption and high degradation rate. The former is cured by light-trapping techniques, whereas the latter is a matter of fabrication details. Interdiffusion of the material components and formation of subsequent interlayers at the front/back region can change the optical/electrical properties and performance/stability of the device. We model the degradation of the ultrathin CdTe film devices considering the material interdiffusion and interlayers formation: CdTeS, CdZnTe, Cu x Te (i.e., Te/Cu bilayer), and oxide interlayers (i.e., CdTeO3). The diffusion rate of the materials is considered separately and the reactions that change the interlayer's properties are studied. Additionally, a back contact of single-walled carbon nanotube showed a higher stability than the metallic contacts. A new time-dependent approach is applied to simulate the degradation rate due to formation of any interlayer. It is shown that the materials interdiffusion causes a defect increment under thermal stress and illumination. The metallic back contact accelerates the degradation, whereas single-walled carbon nanotubes show the highest stability. A SCAPS simulator was used because of its ability in defining the properties of the back contact and metastabilities at the interface layers. The properties of the layers were taken from the experimental data reported in the literature.

  19. Amoebae and other protozoa in material samples from moisture-damaged buildings.

    Science.gov (United States)

    Yli-Pirilä, Terhi; Kusnetsov, Jaana; Haatainen, Susanna; Hänninen, Marja; Jalava, Pasi; Reiman, Marjut; Seuri, Markku; Hirvonen, Maija-Riitta; Nevalainen, Aino

    2004-11-01

    Mold growth in buildings has been shown to be associated with adverse health effects. The fungal and bacterial growth on moistened building materials has been studied, but little attention has been paid to the other organisms spawning in the damaged materials. We examined moist building materials for protozoa, concentrating on amoebae. Material samples (n = 124) from moisture-damaged buildings were analyzed for amoebae, fungi, and bacteria. Amoebae were detected in 22% of the samples, and they were found to favor cooccurrence with bacteria and the fungi Acremonium spp., Aspergillus versicolor, Chaetomium spp., and Trichoderma spp. In addition, 11 seriously damaged samples were screened for other protozoa. Ciliates and flagellates were found in almost every sample analyzed. Amoebae are known to host pathogenic bacteria, such as chlamydiae, legionellae, and mycobacteria and they may have a role in the complex of exposure that contributes to the health effects associated with moisture damage in buildings.

  20. SiO2-TiO2 materials for diuron photocatalytic degradation

    OpenAIRE

    Bernardes, Arthur Alaim; Bulhosa, Maria Carolina Salum; Gonçalves, Fábio Ferreira; D'Oca, Marcelo Gonçalves Montes; Wolke, Silvana Inês; Santos, João Henrique Zimnoch dos

    2011-01-01

    SiO2-TiO2 materials prepared by sol-gel method were evaluated in the photocatalytic degradation of diuron. The materials were prepared with and without surfactant cetyltrimethylammonium chloride at different temperatures (25, 50 and 100 oC). The samples were characterized by N2 adsorptiondesorption measurements, scanning electron microscopy, X-ray diffraction, ultraviolet-visible diffuse reflectance spectroscopy and infrared diffuse reflectance spectroscopy. The results showed tha...

  1. Measurement of natural radioactivity in building materials used in Urumqi, China.

    Science.gov (United States)

    Ding, Xiang; Lu, Xinwei; Zhao, Caifeng; Yang, Guang; Li, Nan

    2013-07-01

    Building materials contain natural radionuclides (226)Ra, (232)Th and (40)K, which cause direct radiation exposure of the public. The concentrations of (226)Ra, (232)Th and (40)K in commonly used building materials of Urumqi, China have been analysed using gamma-ray spectrometry. The concentrations of (226)Ra, (40)K and (232)Th in the studied building materials range from 19.8 to 87.4, from 273.3 to 981.2 and from 11.6 to 47.7 Bq kg(-1), respectively. The radium equivalent activity (Raeq), gamma index (Iγ) and alpha index (Iα) were calculated to assess the radiation hazards to people living in dwellings made of the materials studied. The calculated Raeq values of all the building materials are lower than the limit of 370 Bq kg(-1) for building materials. The values of Iγ and Iα of all the building materials are less than unity. The study shows that these materials may be safely used as construction materials and do not pose significant radiation hazards.

  2. Recycling and reuse of chosen kinds of waste materials in a building industry

    Science.gov (United States)

    Ferek, B.; Harasymiuk, J.; Tyburski, J.

    2016-08-01

    The article describes the current state of knowledge and practice in Poland concerning recycling as a method of reuse of chosen groups of waste materials in building industry. The recycling of building scraps is imposed by environmental, economic and technological premises. The issue of usage of sewage residues is becoming a problem of ever -growing gravity as the presence of the increasing number of pernicious contaminants makes their utilization for agricultural purposes more and more limited. The strategies of using waste materials on Polish building sites were analyzed. The analysis of predispositions to salvage for a group of traditional materials, such as: timber, steel, building debris, insulation materials, plastics, and on the example of new materials, such as: artificial light aggregates made by appropriate mixing of siliceous aggregates, glass refuses and sewage residues in order to obtain a commodity which is apt for economic usage also was made in the article. The issue of recycling of waste materials originating from building operations will be presented in the context of the binding home and EU legal regulations. It was proved that the level of recycling of building wastes in Poland is considerably different from one which is achieved in the solid market economies, both in quantity and in assortment. The method of neutralization of building refuses in connection with special waste materials, which are sewage sludge that is presented in the article may be one of the alternative solutions to the problem of recycling of these wastes not only on the Polish scale.

  3. Materials Degradation Issues in the U.S. High-Level Nuclear Waste Repository

    Energy Technology Data Exchange (ETDEWEB)

    K.G. Mon; F. Hua

    2005-04-12

    This paper reviews the state-of-the-art understanding of the degradation processes by the Yucca Mountain Project (YMP) with focus on interaction between the in-drift environmental conditions and long-term materials degradation of waste packages and drip shields within the repository system during the first 10,000-years after repository closure. This paper provides an overview of the degradation of the waste packages and drip shields in the repository after permanent closure of the facility. The degradation modes discussed in this paper include aging and phase instability, dry oxidation, general and localized corrosion, stress corrosion cracking, and hydrogen induced cracking of Alloy 22 and titanium alloys. The effects of microbial activity and radiation on the degradation of Alloy 22 and titanium alloys are also discussed. Further, for titanium alloys, the effects of fluorides, bromides, and galvanic coupling to less noble metals are considered. It is concluded that the materials and design adopted will provide sufficient safety margins for at least 10,000-years after repository closure.

  4. Investigation of thermal effect on exterior wall surface of building material at urban city area

    Energy Technology Data Exchange (ETDEWEB)

    Md Din, Mohd Fadhil; Dzinun, Hazlini; Ponraj, M.; Chelliapan, Shreeshivadasan; Noor, Zainura Zainun [Institute of Environmental Water Resources and Management (IPASA), Faculty of Civil Engineering, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor (Malaysia); Remaz, Dilshah [Faculty of Built Environment, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor (Malaysia); Iwao, Kenzo [Nagoya Institute of Technology, Nagoya (Japan)

    2012-07-01

    This paper describes the investigation of heat impact on the vertical surfaces of buildings based on their thermal behavior. The study was performed based on four building materials that is commonly used in Malaysia; brick, concrete, granite and white concrete tiles. The thermal performances on the building materials were investigated using a surface temperature sensor, data logging system and infrared thermography. Results showed that the brick had the capability to absorb and store heat greater than other materials during the investigation period. The normalized heat (total heat/solar radiation) of the brick was 0.093 and produces high heat (51% compared to granite), confirming a substantial amount of heat being released into the atmosphere through radiation and convection. The most sensitive material that absorbs and stores heat was in the following order: brick > concrete > granite > white concrete tiles. It was concluded that the type of exterior wall material used in buildings had significant impact to the environment.

  5. Investigation of thermal effect on exterior wall surface of building material at urban city area

    Directory of Open Access Journals (Sweden)

    Mohd Fadhil Md Din, Hazlini Dzinun, M. Ponraj, Shreeshivadasan Chelliapan, Zainura Zainun Noor, Dilshah Remaz, Kenzo Iwao

    2012-01-01

    Full Text Available This paper describes the investigation of heat impact on the vertical surfaces of buildings based on their thermal behavior. The study was performed based on four building materials that is commonly used in Malaysia; brick, concrete, granite and white concrete tiles. The thermal performances on the building materials were investigated using a surface temperature sensor, data logging system and infrared thermography. Results showed that the brick had the capability to absorb and store heat greater than other materials during the investigation period. The normalized heat (total heat/solar radiation of the brick was 0.093 and produces high heat (51% compared to granite, confirming a substantial amount of heat being released into the atmosphere through radiation and convection. The most sensitive material that absorbs and stores heat was in the following order: brick > concrete > granite > white concrete tiles. It was concluded that the type of exterior wall material used in buildings had significant impact to the environment.

  6. Thermal/chemical degradation of ceramic cross-flow filter materials

    Energy Technology Data Exchange (ETDEWEB)

    Alvin, M.A.; Lane, J.E.; Lippert, T.E.

    1989-11-01

    This report summarizes the 14-month, Phase 1 effort conducted by Westinghouse on the Thermal/Chemical Degradation of Ceramic Cross-Flow Filter Materials program. In Phase 1 expected filter process conditions were identified for a fixed-bed, fluid-bed, and entrained-bed gasification, direct coal fired turbine, and pressurized fluidized-bed combustion system. Ceramic cross-flow filter materials were also selected, procured, and subjected to chemical and physical characterization. The stability of each of the ceramic cross-flow materials was assessed in terms of potential reactions or phase change as a result of process temperature, and effluent gas compositions containing alkali and fines. In addition chemical and physical characterization was conducted on cross-flow filters that were exposed to the METC fluid-bed gasifier and the New York University pressurized fluidized-bed combustor. Long-term high temperature degradation mechanisms were proposed for each ceramic cross-flow material at process operating conditions. An experimental bench-scale test program is recommended to be conducted in Phase 2, generating data that support the proposed cross-flow filter material thermal/chemical degradation mechanisms. Papers on the individual subtasks have been processed separately for inclusion on the data base.

  7. Radiation-induced electrical degradation experiments in the Japan materials testing reactor

    Energy Technology Data Exchange (ETDEWEB)

    Farnum, E.; Scharborough, K. [Los Alamos National Lab., NM (United States); Shikama, Tatsuo [and others

    1995-04-01

    The objective of this experiment is to determine the extent of degradation during neutron irradiation of electrical and optical properties of candidate dielectric materials. The goals are to identify promising dielectrics for ITER and other fusion machines for diagnostic applications and establish the basis for optimization of candidate materials. An experiment to measure radiation-induced electrical degradation (REID) in sapphire and MgO-insulated cables was conducted at the JMTR light water reactor. The materials were irradiated at about 260 {degree}C to a fluence of 3{times}10{sup 24} n/m{sup 2} (E>1 MeV) with an applied DC electric field between 100 kV/m and 500 kV/m.

  8. Building materials as intrinsic sources of sulphate: A hidden face of salt weathering of historical monuments investigated through multi-isotope tracing (B, O, S)

    Energy Technology Data Exchange (ETDEWEB)

    Kloppmann, W., E-mail: w.kloppmann@brgm.fr [BRGM, BP 6009, F-45060 Orleans cedex 2 (France); Bromblet, P.; Vallet, J.M. [CICRP, 21, rue Guibal, F-13003 Marseille (France); Verges-Belmin, V. [LRMH, 29, rue de Paris, F-77420 Champs sur Marne (France); Rolland, O. [Independent restorer, 3, rue du Gue, 37270 Montlouis s/Loire (France); Guerrot, C. [BRGM, BP 6009, F-45060 Orleans cedex 2 (France); Gosselin, C. [BRGM, BP 6009, F-45060 Orleans cedex 2 (France); LRMH, 29, rue de Paris, F-77420 Champs sur Marne (France)

    2011-04-01

    Sulphate neoformation is a major factor of degradation of stone monuments. Boron, sulphur and oxygen isotope signatures were investigated for five French historical monuments (Bourges, Chartres and Marseille cathedrals, Chenonceau castle, and Versailles garden statues) to investigate the role of intrinsic sulphate sources (gypsum plasters and mortars) in stone degradation, compared to the influence of extrinsic sources such as atmospheric pollution. Gypsum plasters and gypsum-containing mortars fall systematically in the {delta}{sup 34}S and {delta}{sup 18}O range of Paris Basin Eocene evaporites indicating the origin of the raw materials (so-called 'Paris plaster'). Black crusts show the typical S and O isotope signatures observed elsewhere in Europe that can be attributed to atmospheric pollution, together with a marine component for Marseille. Boron isotopes for black crusts indicate coal combustion as principal boron source. Mortar isotope compositions discriminate three types, one similar to gypsum plasters, one strongly depleted in {sup 34}S, attributed to pyrite oxidation, and a third one close to atmospheric sulphates. The isotopic composition of sulphates and boron of most degraded building stones of the different monuments is well explained by the identified sulphate sources. In several cases (in particular for Chenonceau and Bourges, to some extent for Chartres), the impact of gypsum plaster as building and restoration material on the degradation of the stones in its vicinity was clearly demonstrated. The study illustrates the usefulness of multi-isotope studies to investigate stone degradation factors, as the combination of several isotope systematics increases the discriminatory power of isotope studies with respect to contaminant sources. - Research Highlights: {yields} Insight in stone weathering mechanisms by multi-isotope fingerprinting (B, S, O). {yields} Intrinsic sulphate sources (gypsum plaster, mortar) contribute to stone degradation

  9. Low-Cost Phase Change Material for Building Envelopes

    Energy Technology Data Exchange (ETDEWEB)

    Abhari, Ramin [Renewable Energy Group

    2015-08-06

    A low-cost PCM process consisting of conversion of fats and oils to PCM-range paraffins, and subsequent “encapsulation” of the paraffin using conventional plastic compounding/pelletizing equipment was demonstrated. The PCM pellets produced were field-tested in a building envelope application. This involved combining the PCM pellets with cellulose insulation, whereby 33% reduction in peak heat flux and 12% reduction in heat gain was observed (average summertime performance). The selling price of the PCM pellets produced according to this low-cost process is expected to be in the $1.50-$3.00/lb range, compared to current encapsulated PCM price of about $7.00/lb. Whole-building simulations using corresponding PCM thermal analysis data suggest a payback time of 8 to 16 years (at current energy prices) for an attic insulation retrofit project in the Phoenix climate area.

  10. The potential of vernacular materials to the sustainable building design

    OpenAIRE

    Fernandes, Jorge Emanuel Pereira; Mateus, Ricardo; Bragança, L.

    2014-01-01

    Publicado em "Vernacular heritage and earthen architecture : contributions for sustainable development", ISBN 978-1-138-00083-4 Vernacular architecture embodies a plurality of constraints from places where it belongs, in which the use of local materials and techniques is one of the main features. When compared with industrially-produced materials, vernacular materials have low environmental impacts, being an alternative for sustainable construction. The increasing use of new industrially-p...

  11. Magnetization of Steel Building Materials and Structures in the Natural Geomagnetic Field

    Directory of Open Access Journals (Sweden)

    E. Čermáková

    2005-01-01

    Full Text Available This paper presents the physical basis of the magnetic properties of ferromagnetic materials and shows their relationships with external geomagnetic field. It graphically processes the experimental data detected by an HMR magnetometer. Taking into account the natural geomagnetic field under the effects of steel U profiles, variations of the natural geomagnetic field in a steel structure building are indicated and the potential existence of Sick Building Syndrome (SBS in these types of buildings is pointed out. 

  12. Assessment of thermal insulation materials and systems for building applications

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-06-01

    The primary goal of the study was to provide a proper foundation for decision making by the federal government, industry, and consumer. The report may be used to identify areas where new test methods and standards are needed to establish new programs for improving thermal performance of buildings, and as a basis for setting new or improved standards after the recommended test programs have been completed.

  13. Material degradation of liquid organic semiconductors analyzed by nuclear magnetic resonance spectroscopy

    Directory of Open Access Journals (Sweden)

    Tatsuya Fukushima

    2015-08-01

    Full Text Available Liquid organic light-emitting diodes (liquid OLEDs are unique devices consisting only of liquid organic semiconductors in the active layer, and the device performances have been investigated recently. However, the device degradation, especially, the origin has been unknown. In this study, we show that material degradation occurs in liquid OLEDs, whose active layer is composed of carbazole with an ethylene glycol chain. Nuclear magnetic resonance (NMR experiments clearly exhibit that the dimerization reaction of carbazole moiety occurs in the liquid OLEDs during driving the devices. In contrast, cleavages of the ethylene glycol chain are not detected within experimental error. The dimerization reaction is considered to be related to the device degradation.

  14. Development of Multiscale Materials Modeling Techniques and Coarse- Graining Strategies for Predicting Materials Degradation in Extreme Irradiation Environments

    Energy Technology Data Exchange (ETDEWEB)

    Wirth, Brian [Univ. of Tennessee, Knoxville, TN (United States)

    2016-01-12

    Exposure of metallic structural materials to irradiation environments results in significant microstructural evolution, property changes and performance degradation, which limits the extended operation of current generation light water reactors and restricts the design of advanced fission and fusion reactors [1-8]. This effect of irradiation on materials microstructure and properties is a classic example of an inherently multiscale phenomenon, as schematically illustrated in Figure 1a. Pertinent processes range from the atomic nucleus to structural component length scales, spanning more than 15 orders of magnitude. Time scales bridge more than 22 orders of magnitude, with the shortest being less than a femtosecond [1,8]. Further, the mix of radiation-induced features formed and the corresponding property degradation depend on a wide range of material and irradiation variables. This emphasizes the importance of closely integrating models with high-resolution experimental characterization of the evolving radiation- damaged microstructure, including measurements performed in-situ during irradiation. In this article, we review some recent successes through the use of closely coordinated modeling and experimental studies of the defect cluster evolution in irradiated body-centered cubic materials, followed by a discussion of outstanding challenges still to be addressed, which are necessary for the development of comprehensive models of radiation effects in structural materials.

  15. Potentially harmful secondary metabolites produced by indoor Chaetomium species on artificially and naturally contaminated building materials

    DEFF Research Database (Denmark)

    Dosen, Ina; Nielsen, Kristian Fog; Clausen, Geo

    2017-01-01

    , have been screened for, and thus detected in buildings. In this study, we used a liquid chromatography-high resolution mass spectrometry approach to screen both artificially and naturally infected building materials for all the Chaetomium metabolites described in the literature. Pure agar cultures were...

  16. GROWTH RESPONSE OF STACHYBOTRYS CHARTARUM TO MOISTURE VARIATION ON COMMON BUILDING MATERIALS

    Science.gov (United States)

    The mold Stachybotrys chartarum has been found to be associated with idiopathic pulmonary hemorrhage in infants and has been studied for toxin production and its occurrence in water damaged buildings. Growth of S. chartarum on building materials such as drywall has been frequentl...

  17. Investigation of Material Performance Degradation for High-Strength Aluminum Alloy Using Acoustic Emission Method

    Directory of Open Access Journals (Sweden)

    Yibo Ai

    2015-02-01

    Full Text Available Structural materials damages are always in the form of micro-defects or cracks. Traditional or conventional methods such as micro and macro examination, tensile, bend, impact and hardness tests can be used to detect the micro damage or defects. However, these tests are destructive in nature and not in real-time, thus a non-destructive and real-time monitoring and characterization of the material damage is needed. This study is focused on the application of a non-destructive and real-time acoustic emission (AE method to study material performance degradation of a high-strength aluminum alloy of high-speed train gearbox shell. By applying data relative analysis and interpretation of AE signals, the characteristic parameters of materials performance were achieved and the failure criteria of the characteristic parameters for the material tensile damage process were established. The results show that the AE method and signal analysis can be used to accomplish the non-destructive and real-time detection of the material performance degradation process of the high-strength aluminum alloy. This technique can be extended to other engineering materials.

  18. Further Development of Selective Dyeing Method for Detecting Chrysotile Asbestos in Building Materials

    Science.gov (United States)

    Oke, Y.; Yamasaki, N.; Maeta, N.; Fujimaki, H.; Hashida, T.

    2008-02-01

    Extensive usage of chrysotile asbestos has resulted in the remains of large numbers of chrysotile asbestos-containing buildings to be surveyed. We have recently developed a simple dyeing method for detecting chrysotile asbestos in building materials, which involves pretreatment with calcium-chelating agent and dyeing treatment with magnesium-chelating organic dyes. In this study, we further developed a method which eliminates dyed asbestos substitutes containing magnesium, potentially present in building materials. In the new method, post-treatment with formic acid was conducted to dissolve the non-chrysotile asbestos materials in order to delineate dyed chrysotile asbestos. The calcium-masking process was also shown to be an essential process even when the post-treatment was conducted. It was shown that the new method developed in this study may enable us to dye chrysotile asbestos only without detecting asbestos substitutes in building materials.

  19. Monte Carlo simulation of indoor external exposure due to gamma-emitting radionuclides in building materials

    Science.gov (United States)

    Deng, Jun; Cao, Lei; Su, Xu

    2014-10-01

    The use of building materials containing naturally occurring radionuclides, such as 40K, 238U, 232Th and their progeny, could lead to external exposures to the residents of such buildings. In this paper, a set of models are constructed to calculate the specific effective dose rates (the effective dose rate per Bq/kg of 40K, the 238U series, and the 232Th series) imposed on residents by building materials with the MCNPX code. The effect of chemical composition, position concerned in the room and thickness as well as density of material is analyzed. In order to facilitate more precise assessment of indoor external dose due to gamma-emitting radionuclides in building materials, three regressive expressions are proposed and validated by measured data to calculate specific effective rates for 40K. the 238U series and the 232Th series, respectively.

  20. Monte Carlo Simulation of Indoor External Exposure due to Gamma-emitting Radionuclides in Building Materials

    CERN Document Server

    Deng, Jun; Su, Xu

    2014-01-01

    The use of building materials containing naturally occurring radionuclides,such as K-40, U-238 and Th-232 and their progeny, could lead to external exposures of the residents of such buildings. In this paper, a set of models are set up to calculate the specific effective dose rates(the effective dose rate per Bq/kg of K-40, U-238 series, and Th-232 series) imposed to residents by building materials with MCNPX code. Effect of chemical composition, position concerned in the room and thickness as well as density of material is analyzed. In order to facilitate more precise assessment of indoor external dose due to gamma emitting radionuclides in building materials, three regressive expressions are proposed and validated by measured data to calculate specific effective rate for K-40, U-238 series and Th-232 series, respectively.

  1. 29 CFR 779.355 - Classification of lumber and building materials sales.

    Science.gov (United States)

    2010-07-01

    ... LABOR STANDARDS ACT AS APPLIED TO RETAILERS OF GOODS OR SERVICES Exemptions for Certain Retail or... business rather than a function of a retail merchant; (2) Sales of lumber and building materials in...

  2. Radioactivity of building materials and the gamma radiation in dwellings in Belo Horizonte, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Marques, Ludmila Souza [Centro Federal de Educacao Tecnologica de Minas Gerais (CEFET-MG), Belo Horizonte, MG (Brazil)]. E-mail: ludmiga@yahoo.com.br; Rocha, Zildete [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil). Servico de Quimica e Radioquimica]. E-mail: rochaz@cdtn.br

    2007-07-01

    Building materials are known to contain naturally occurring radioactive materials (NORM). The radionuclides which contribute to the external exposure are 40 K and the gamma emitters members of the natural decay series {sup 238}U, {sup 235}U and {sup 232}Th. Samples of the statistically more important buildings materials utilized in the Metropolitan area of Belo Horizonte were collected and their uranium and thorium concentration were determined by INAA. The gamma emitters were spectrometrically determined by solid state detectors HPGe in a very low background laboratory. A model room was used for calculating the indoor mean exposure in dwellings. Due to the lack of regulation for radioactivity in buildings in Brazil, the measured activity concentration was compared with those of other countries. A discussion about the utilization of building material containing TENORM industrial residues is presented. (author)

  3. Degradability of injectable calcium sulfate/mineralized collagen-based bone repair material and its effect on bone tissue regeneration

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Zonggang, E-mail: chenzg@sdu.edu.cn [National Glycoengineering Research Center, Shandong University, Jinan 250100 (China); Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Kang, Lingzhi [National Glycoengineering Research Center, Shandong University, Jinan 250100 (China); Meng, Qing-Yuan [Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Liu, Huanye [Department of Prosthodontics, School of Stomatology, China Medical University, Shenyang 110001 (China); Wang, Zhaoliang [Jinan Military General Hospital of PLA, Jinan 250031 (China); Guo, Zhongwu, E-mail: zwguo@sdu.edu.cn [National Glycoengineering Research Center, Shandong University, Jinan 250100 (China); Cui, Fu-Zhai, E-mail: cuifz@mail.tsinghua.edu.cn [Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China)

    2014-12-01

    The nHAC/CSH composite is an injectable bone repair material with controllable injectability and self-setting properties prepared by introducing calcium sulfate hemihydrate (CSH) into mineralized collagen (nHAC). When mixed with water, the nHAC/CSH composites can be transformed into mineralized collagen/calcium sulfate dihydrate (nHAC/CSD) composites. The nHAC/CSD composites have good biocompatibility and osteogenic capability. Considering that the degradation behavior of bone repair material is another important factor for its clinical applications, the degradability of nHAC/CSD composites was studied. The results showed that the degradation ratio of the nHAC/CSD composites with lower nHAC content increased with the L/S ratio increase of injectable materials, but the variety of L/S ratio had no significant effect on the degradation ratio of the nHAC/CSD composites with higher nHAC content. Increasing nHAC content in the composites could slow down the degradation of nHAC/CSD composite. Setting accelerator had no significant effect on the degradability of nHAC/CSD composites. In vivo histological analysis suggests that the degradation rate of materials can match the growth rate of new mandibular bone tissues in the implanted site of rabbit. The regulable degradability of materials resulting from the special prescriptions of injectable nHAC/CSH composites will further improve the workability of nHAC/CSD composites. - Highlights: • The nHAC/CSH composite can be as an injectable bone repair material. • The L/S ratio and nHAC content have a significant effect on material degradability. • The degradability of bone materials can be regulated to match tissue repair. • The regulable degradability will further improve the workability of bone materials.

  4. Radiation-induced electrical degradation experiments in the Japan materials testing reactor

    Science.gov (United States)

    Farnum, Eugene H.; Shikama, Tatsuo; Narui, Minoru; Sagawa, Tsutomu; Scarborough, Kent

    1996-02-01

    An experiment to measure radiation-induced electrical degradation (RIED) in a sapphire sample and in three MgO-insulated cables was conducted at the JMTR light water reactor. The materials were irradiated at about 260°C to a fluence of 3 × 1024 n/m 2 ( E > 1 MeV) with an applied DC electric field between 100 kV/m and 500 kV/m. Even though the results for the sapphire sample are somewhat ambiguous because of an unexplained offset current of about 0.6 μA substantial degradation was not observed in the sapphire: instead, radiation-induced conductivity (RIC) seemed to decrease slightly during the experiment. Substantial increase in leakage current, that increased with applied electric field, occurred in the MgO-insulated cables. This increased conductivity disappeared when the reactor was shut down and sample temperature returned to ambient. However, the physical degradation apparently remained in the material while the reactor was off because restarting the irradiation brought the conductivity back to its previous, degraded, reactor-on value. This effect is different from the RIED effect reported by Hodgson but is similar to previous results reported by Shikama et al. Considerable data were taken to determine the sample temperature and leakage currents during the irradiation.

  5. Optimization of a phase change material wallboard for building use

    Energy Technology Data Exchange (ETDEWEB)

    Kuznik, Frederic; Virgone, Joseph [Thermal Sciences Center of Lyon, CNRS, UMR 5008, INSA de Lyon, Universite Lyon 1, Bat Freyssinet, 40 Rue des Arts, 69621 Villeurbanne Cedex (France); Noel, Jean [Free-lance Scientific Software Developer, 15 Place Carnot, 69002 Lyon (France)

    2008-08-15

    In construction, the use of phase change materials (PCM) allows the storage/release of energy from the solar radiation and/or internal loads. The application of such materials for lightweight construction (e.g., a wood house) makes it possible to improve thermal comfort and reduce energy consumption. A wallboard composed of a new PCM material is investigated in this paper to enhance the thermal behavior of a lightweight internal partition wall. The paper focuses on the optimization of phase change material thickness. The in-house software CODYMUR is used to optimize the PCM wallboard by the means of numerical simulations. The results show that an optimal PCM thickness exists. The optimal PCM thickness value is then calculated for use in construction. (author)

  6. Understanding Fundamental Material Degradation Processes in High Temperature Aggressive Chemomechanical Environments

    Energy Technology Data Exchange (ETDEWEB)

    Stubbins, James; Gewirth, Andrew; Sehitoglu, Huseyin; Sofronis, Petros; Robertson, Ian

    2014-01-16

    The objective of this project is to develop a fundamental understanding of the mechanisms that limit materials durability for very high-temperature applications. Current design limitations are based on material strength and corrosion resistance. This project will characterize the interactions of high-temperature creep, fatigue, and environmental attack in structural metallic alloys of interest for the very high-temperature gas-cooled reactor (VHTR) or Next–Generation Nuclear Plant (NGNP) and for the associated thermo-chemical processing systems for hydrogen generation. Each of these degradation processes presents a major materials design challenge on its own, but in combination, they can act synergistically to rapidly degrade materials and limit component lives. This research and development effort will provide experimental results to characterize creep-fatigue-environment interactions and develop predictive models to define operation limits for high-temperature structural material applications. Researchers will study individually and in combination creep-fatigue-environmental attack processes in Alloys 617, 230, and 800H, as well as in an advanced Ni-Cr oxide dispersion strengthened steel (ODS) system. For comparison, the study will also examine basic degradation processes in nichrome (Ni-20Cr), which is a basis for most high-temperature structural materials, as well as many of the superalloys. These materials are selected to represent primary candidate alloys, one advanced developmental alloy that may have superior high-temperature durability, and one model system on which basic performance and modeling efforts can be based. The research program is presented in four parts, which all complement each other. The first three are primarily experimental in nature, and the last will tie the work together in a coordinated modeling effort. The sections are (1) dynamic creep-fatigue-environment process, (2) subcritical crack processes, (3) dynamic corrosion – crack

  7. Study of the degradation of mulch materials in vegetable crops for organic farming

    Science.gov (United States)

    María Moreno, Marta; Mancebo, Ignacio; Moreno, Carmen; Villena, Jaime; Meco, Ramón

    2014-05-01

    Mulching is the most common technique used worldwide by vegetable growers in protected cultivation. For this purpose, several plastic materials have been used, with polyethylene (PE) being the most widespread. However, PE is produced from petroleum derivatives, it is not degradable, and thus pollutes the environment for periods much longer than the crop duration (Martín-Closas and Pelacho, 2011), which are very important negative aspects especially for organic farmers. A large portion of plastic films is left on the field or burnt uncontrollably by the farmers, with the associated negative consequences to the environment (Moreno and Moreno, 2008). Therefore, the best solution is to find a material with a lifetime similar to the crop duration time that can be later incorporated by the agricultural system through a biodegradation process (Martín-Closas and Pelacho, 2011). In this context, various biodegradable materials have been considered as alternatives in the last few years, including oxo-biodegradable films, biopolymer mulches, different types of papers, and crop residues (Kasirajan and Ngouajio, 2012). In this work we evaluate the evolution of different properties related to mulch degradation in both the buried and the superficial (exposed) part of mulch materials of different composition (standard black PE, papers and black biodegradable plastics) in summer vegetable crops under organic management in Castilla-La Mancha (Central Spain). As results, it is remarkable the early deterioration suffered by the buried part of the papers, disappearing completely in the soil at the end of the crop cycles and therefore indicating the total incorporation of these materials to the soil once the crop has finished. In the case of the degradation of the exposed mulch, small differences between crops were observed. In general, all the materials were less degraded under the plants than when receiving directly the solar radiation. As conclusion, biodegradable mulches degrade

  8. Review of Development Survey of Phase Change Material Models in Building Applications

    Directory of Open Access Journals (Sweden)

    Hussein J. Akeiber

    2014-01-01

    Full Text Available The application of phase change materials (PCMs in green buildings has been increasing rapidly. PCM applications in green buildings include several development models. This paper briefly surveys the recent research and development activities of PCM technology in building applications. Firstly, a basic description of phase change and their principles is provided; the classification and applications of PCMs are also included. Secondly, PCM models in buildings are reviewed and discussed according to the wall, roof, floor, and cooling systems. Finally, conclusions are presented based on the collected data.

  9. Evaluation of thermal degradation of polymer based electronic materials by non-destructive testing

    Science.gov (United States)

    Rafiee, P.; Khatibi, G.; Lederer, M.; Zehetbauer, M.

    2017-01-01

    Thermal degradation of polymeric materials used in microelectronic packages was studied by means of experimental modal analysis in combination with finite element methods. The devices were subjected to vibrational loads subsequent to various stages of high temperature storage and their modal response was recorded. Statistical methods and finite element analysis were applied to quantify and evaluate the alteration of the modal response of the packages due to the degradation / delamination of the silver filled epoxy adhesive and the glass filled epoxy resin molding compound. It was shown that changes in the material properties of the molding compound due to surface oxidation is the dominant cause for alteration of the modal response of encapsulated packages exposed to high temperatures.

  10. Degradation of carbon-based materials under ablative conditions produced by a high enthalpy plasma jet

    Directory of Open Access Journals (Sweden)

    Gilberto Petraconi

    2010-04-01

    Full Text Available A stationary experiment was performed to study the degradation of carbon-based materials by immersion in a plasma jet. In the experiment, graphite and C/C composite were chosen as the target materials, and the reactive plasma jet was generated by an air plasma torch. For macroscopic study of the material degradation, the sample’s mass losses were measured as function of the exposure time under various temperatures on the sample surface. A microscopic analysis was then carried out for the study of microscopic aspects of the erosion of material surface. These experiments showed that the mass loss per unit area is approximately proportional to the exposure time and strongly depends on the temperature of the material surface. The mass erosion rate of graphite was appreciably higher than the C/C composite. The ablation rate in the carbon matrix region in C/C composite was also noticeably higher than that in the fiber region. In addition, the latter varied according to the orientation of fibers relatively to the flow direction. These tests indicated an excellent ablation resistance of the C/C composite, thus being a reliable material for rocket nozzles and heat shielding elements of the protection systems of hypersonic apparatuses from aerodynamic heating.

  11. Electrochemical and structural investigations on lithium-ion battery materials and related degradation processes

    OpenAIRE

    2016-01-01

    The introduction of the lithium-ion battery technology in the automotive field has boosted the renaissance of electromobility over the last decade. To improve the energy density and durability of the battery system, analytical approaches have to be developed, which help to understand novel electrode materials and degradation phenomena. In this work, an in situ XRD cell for reflection and transmission geometry was established to investigate the structural changes in LiCoPO4 and Li2S during the...

  12. A Materials Life Cycle Assessment of a Net-Zero Energy Building

    Directory of Open Access Journals (Sweden)

    Laura A. Schaefer

    2013-02-01

    Full Text Available This study analyzed the environmental impacts of the materials phase of a net-zero energy building. The Center for Sustainable Landscapes (CSL is a three-story, 24,350 square foot educational, research, and administrative office in Pittsburgh, PA, USA. This net-zero energy building is designed to meet Living Building Challenge criteria. The largest environmental impacts from the production of building materials is from concrete, structural steel, photovoltaic (PV panels, inverters, and gravel. Comparing the LCA results of the CSL to standard commercial structures reveals a 10% larger global warming potential and a nearly equal embodied energy per square feet, largely due to the CSL’s PV system. As a net-zero energy building, the environmental impacts associated with the use phase are expected to be very low relative to standard structures. Future studies will incorporate the construction and use phases of the CSL for a more comprehensive life cycle perspective.

  13. BUILDING MATERIALS MADE FROM FLUE GAS DESULFURIZATION BY-PRODUCTS

    Energy Technology Data Exchange (ETDEWEB)

    Michael W. Grutzeck; Maria DiCola; Paul Brenner

    2006-03-30

    Flue gas desulphurization (FGD) materials are produced in abundant quantities by coal burning utilities. Due to environmental restrains, flue gases must be ''cleaned'' prior to release to the atmosphere. They are two general methods to ''scrub'' flue gas: wet and dry. The choice of scrubbing material is often defined by the type of coal being burned, i.e. its composition. Scrubbing is traditionally carried out using a slurry of calcium containing material (slaked lime or calcium carbonate) that is made to contact exiting flue gas as either a spay injected into the gas or in a bubble tower. The calcium combined with the SO{sub 2} in the gas to form insoluble precipitates. Some plants have been using dry injection of these same materials or their own Class C fly ash to scrub. In either case the end product contains primarily hannebachite (CaSO{sub 3} {center_dot} 1/2H{sub 2}O) with smaller amounts of gypsum (CaSO{sub 4} {center_dot} 2H{sub 2}O). These materials have little commercial use. Experiments were carried out that were meant to explore the feasibility of using blends of hannebachite and fly ash mixed with concentrated sodium hydroxide to make masonry products. The results suggest that some of these mixtures could be used in place of conventional Portland cement based products such as retaining wall bricks and pavers.

  14. Proactive Management of Materials Degradation - A Review of Principles and Programs

    Energy Technology Data Exchange (ETDEWEB)

    Bond, Leonard J.; Doctor, Steven R.; Taylor, Theodore T.

    2008-08-28

    The U.S. Nuclear Regulatory Commission (NRC) has undertaken a program to lay the technical foundation for defining proactive actions so that future degradation of materials in light water reactors (LWRs) is limited and, thereby, does not diminish either the integrity of important LWR components or the safety of operating plants. This technical letter report was prepared by staff at Pacific Northwest National Laboratory in support of the NRC Proactive Management of Materials Degradation (PMMD) program and relies heavily on work that was completed by Dr. Joseph Muscara and documented in NUREG/CR-6923. This report concisely explains the basic principles of PMMD and its relationship to prognostics, provides a review of programs related to PMMD being conducted worldwide, and provides an assessment of the technical gaps in PMMD and prognostics that need to be addressed. This technical letter report is timely because the majority of the U.S. reactor fleet is applying for license renewal, and many plants are also applying for increases in power rating. Both of these changes could increase the likelihood of materials degradation and underline, therefore, the interest in proactive management in the future.

  15. Prediction and classification of the degradation state of plastic materials used in modern and contemporary art

    Science.gov (United States)

    Manfredi, M.; Barberis, E.; Marengo, E.

    2017-01-01

    Today, artworks partially or completely made of plastic materials can be found in almost all international museums and collections. The deterioration of these objects is now becoming evident mainly because these synthetic materials are not designed for a long life and the characterization of their state of conservation can help curators and conservators. In this research we investigated the applicability of a portable attenuated total reflection (ATR) infrared spectrometer for the non-invasive characterization and for monitoring the degradation of plastics used in modern and contemporary art. Several polypropylene and polycarbonate samples were artificially aged in solar box, simulating about 200 years of museum light exposure, and they were monitored with the portable ATR, creating an infrared library of the conservation state of plastics. Through the use of chemometric techniques like principal component analysis-linear discriminant analysis and partial least square—discriminant analysis, we built a robust degradation model of each material that can be used to predict and classify the degradation state of artworks and to identify the priority of intervention in the museum collections. Portable ATR coupled to multivariate statistics can be employed for taking care of plastic artworks as it is non-invasive, the analysis is very fast and it can be performed directly in situ.

  16. Suitable Friction Sliding Materials for Base Isolation of Masonry Buildings

    Directory of Open Access Journals (Sweden)

    Radhikesh P. Nanda

    2012-01-01

    Full Text Available A feasibility study of friction base isolation system for seismic protection has been performed. Four different sliding interfaces, namely, green marble/High Density Poly Ethylene (HDPE, green marble/green marble, green marble/geosynthetic, and green marble/ rubber layers have been studied through experimental and analytical investigations. The experimental investigations show that the coefficient of friction values of these interfaces lies in the desirable range for seismic protection, i.e., 0.05 to 0.15. The analytical investigation reveals that most of these sliding interfaces are effective in reducing spectral accelerations up to 50% and the sliding displacement is restricted within plinth projection of 75 mm (3 in. Green marble and geosynthetic are found to be better alternatives for use in friction isolation system with equal effectiveness of energy dissipation and limiting the earthquake energy transmission to super structure during strong earthquake leading to a low cost, durable solution for earthquake protection of masonry buildings.

  17. High Strength Phosphogypsum and Its Use as a Building Material

    Science.gov (United States)

    Kanno, Wellington Massayuki; Rossetto, Hebert Luis; de Souza, Milton Ferreira; Máduar, Marcelo Francis; de Campos, Marcia Pires; Mazzilli, Barbara Paci

    2008-08-01

    A new process (patent applied) that works equally well with both plaster of mineral gypsum and phosphogypsum for the preparation of gypsum components, UCOS, has been developed. The process consists of the following steps: humidification of plaster by fine water droplets, uni-axial compression, hydration reaction and drying. Strong hydrogen bonds develop among the crystals together with adhesion provided by confined water that accounts for nearly 70% of the adhesion forces. By reducing the plaster to water ratio to close the minimum necessary, new features are generated. An experimental house has been constructed, in which walls and ceilings have been built of gypsum and phosphogypsum. Since phosphogypsum potentially contain radioactive elements, the application of an activity concentration index to the phosphogypsum employed in the building was carried out.

  18. Degradation of materials properties in space-overview of LDEF (Long Duration Exposure Facility)

    Science.gov (United States)

    Kinard, William H.; O'Neal, Robert L.; Martin, Glenna D.

    1991-01-01

    This paper presents an overview of the initial observations of the Long Duration Exposure Facility and, in particular, the degradation of the onboard materials. The LDEF was retrieved from space on January 12, 1990, during the Space Shuttle STS Mission 32 after having remained in space for almost 6 years. Ongoing studies of this retrieved hardware are providing a wealth of basic science data on the environments of near-earth space and the synergistic effects of these space environments on a large array of typical spacecraft materials and systems.

  19. Development of phase change materials based microencapsulated technology for buildings: A review

    Energy Technology Data Exchange (ETDEWEB)

    Tyagi, V.V.; Kaushik, S.C. [Centre for Energy Studies, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016 (India); Tyagi, S.K. [School of Infrastructure Technology and Resource Management, Shri Mata Vaishno Devi University, Katra 182320, J and K (India); Akiyama, T. [Center for Advanced Research of Energy Conversion Materials, Hokkaido University, Kita 13, Nishi 8, Kita-ku, Sapporo 060-86283 (Japan)

    2011-02-15

    Thermal energy storage (TES) systems using phase change material (PCM) have been recognized as one of the most advanced energy technologies in enhancing the energy efficiency and sustainability of buildings. Now the research is focus on suitable method to incorporate PCMs with building. There are several methods to use phase change materials (PCMs) in thermal energy storage (TES) for different applications. Microencapsulation is one of the well known and advanced technologies for better utilization of PCMs with building parts, such as, wall, roof and floor besides, within the building materials. Phase change materials based microencapsulation for latent heat thermal storage (LHTS) systems for building application offers a challenging option to be employed as effective thermal energy storage and a retrieval device. Since the particular interest in using microencapsulation PCMs for concrete and wall/wallboards, the specific research efforts on both subjects are reviewed separately. This paper presents an overview of the previous research work on microencapsulation technology for thermal energy storage incorporating the phase change materials (PCMs) in the building applications, along with few useful conclusive remarks concluded from the available literature. (author)

  20. EXPERIMENTAL DEVELOPMENT OF BIO-BASED POLYMER MATRIX BUILDING MATERIAL AND FISH BONE DIAGRAM FOR MATERIAL EFFECT ON QUALITY

    Directory of Open Access Journals (Sweden)

    Asmamaw Tegegne

    2014-06-01

    Full Text Available These days cost of building materials are continuously increasing and the conventional construction materials for this particular purpose become low and low. The weight of conventional construction materials particularly building block is heavy and costly due to particularly cement. Thus, the objective of this paper is to develop an alternative light weight, high strength and relatively cost effective building material that satisfy the quality standard used in the country. A bio-based polymer matrix composite material for residential construction was experimentally developed. Sugar cane bagasse, thermoplastics (polyethylene g roup sand and red ash were used as materials alternatively. Mixing of the additives,melting of the hermoplastics, molding and curing (dryingwere the common methods used on the forming process of the samples. Mechanical behavior evaluation (testing of the product was carried out. Totally 45 specimens were produced and three replicate tests were performed per each test type. Quality analysis was carried out for group B material using Ishikawa diagram. The tensile strength of group A specimen was approximately 3 times greater than that of group B specimens. The compression strength of group A specimens were nearly 2 times greater than group B. Comparing to the conventional building materials(concert block and agrostoneproduced in the country, which the compression strength is 7Mpa and 16Mpa respectively, the newly produced materials show much better results in which Group A is 25.66 Mpa and group B is 16.66 Mpa. energy absorption capacity of group A specimens was approximately 3 times better than that of group B. Water absorption test was carried out for both groups and both showed excellent resistivity. Group A composite material specimens, showed better results in all parameters.

  1. Use of Advanced Plastic Materials in Nigeria: Performance Assessment of Expanded Polystyrene Building Technology System

    Directory of Open Access Journals (Sweden)

    Anthony Nkem Ede (PhD

    2016-08-01

    Full Text Available The provision of affordable residential houses for the masses in the developing nations has been a mirage over the years and the future does not portend good as the cost of adopting conventional concrete material technologies is escalating while so many environmental issues like climate change are being raised in the recent times.To circumvent this poor housing provision trend, some innovative construction materials and technologies are being introduced to facilitate unique modular designs, reduction of labour, decline in the depletion of exhaustible materials,savings of time and fund. One of such materials is the expanded polystyrene. The introduction of advanced plastic materials and in particular the expanded polystyrene building technologies in the Nigerian constructionindustry will be a very useful and brilliant initiative that will aid the reduction of cost of construction and facilitate access to affordable houses for the masses.This researchaims at studying the applications of this innovative plastic material in the Nigerian building industry with special regard to the performance perception by the clients and the end users. A building estate where expanded polystyrene building technology has been predominantly used in Abuja is considered as a case study. Questionnaires were distributed among clients and residents of the building estate and statistical tools were used to analyse the data collected. Great satisfaction verified among the clients and residents and the high ranking performance confirmed for recyclability, reliability, versatility and moisture resistance of EPS building products all herald a great future for the applications of this advanced building products in the Nigerian building industry.

  2. A novel source of atmospheric H2: abiotic degradation of organic material

    Science.gov (United States)

    Lee, H.; Rahn, T.; Throop, H. L.

    2012-11-01

    Molecular hydrogen (H2) plays an important role in atmospheric chemistry by competing for reactions with the hydroxyl radical (OH·) and contributing to the production of H2O in the stratosphere, indirectly influencing stratospheric ozone concentrations. The dominant pathway for loss of H2 from the atmosphere is via microbially-mediated soil uptake, although the magnitude of this loss is still regarded as highly uncertain. Recent studies have shown that abiotic processes such as photochemically mediated degradation (photodegradation) of organic material result in direct emissions of carbon (C) and nitrogen (N)-based trace gases as well as H2. This H2 production has important implications on source-sink dynamics of H2 at the soil-atmosphere interface and thus it is important to quantify its variability over a range of plant types and materials. Here, we show laboratory observations of H2 production and its temperature dependence during abiotic degradation of four plant litter types as well as pure cellulose and high lignin content woody material. A greater amount of H2 was produced in the absence of solar radiation than from photodegradation alone, verifying that low temperature thermal degradation of plant litter is a source of H2. In addition, we measured a significant release of H2 both in the presence and absence of O2. Our results suggest that abiotic release of H2 during organic matter degradation is ubiquitous in arid ecosystems and may also occur in other terrestrial ecosystems. We propose that because these processes occur at the soil-atmosphere interface, they provide a previously unrecognized proximal source of H2 for microbial uptake and confound interpretation of direct measurements of atmospheric uptake that are important for constraining the global H2 budget.

  3. A Review of Performance of Insulating Material in Buildings

    Directory of Open Access Journals (Sweden)

    Tazyeen Ahmad

    2014-11-01

    Full Text Available Today India is a fast developing economy; its GDP is increasing so the per capita income is also increasing. To meet the comfort requirements, especially in scorching summer and chilling winter in one form or other, we need modern amenities like air-conditioners and room heaters. Both need energy (electricity as a fuel to perform their function, so at individual level or at national view point, energy saving has to be done. The phrase will not be wrong: “Let the energy be saved, though the heaven falls”. In this paper, a review of insulation materials along with their properties has been presented. The information given is relevant and useful for architects and engineers. This paper also has glimpses of past and future of insulating materials.

  4. The influence of cathode material on electrochemical degradation of trichloroethylene in aqueous solution.

    Science.gov (United States)

    Rajic, Ljiljana; Fallahpour, Noushin; Podlaha, Elizabeth; Alshawabkeh, Akram

    2016-03-01

    In this study, different cathode materials were evaluated for electrochemical degradation of aqueous phase trichloroethylene (TCE). A cathode followed by an anode electrode sequence was used to support reduction of TCE at the cathode via hydrodechlorination (HDC). The performance of iron (Fe), copper (Cu), nickel (Ni), aluminum (Al) and carbon (C) foam cathodes was evaluated. We tested commercially available foam materials, which provide large electrode surface area and important properties for field application of the technology. Ni foam cathode produced the highest TCE removal (68.4%) due to its high electrocatalytic activity for hydrogen generation and promotion of HDC. Different performances of the cathode materials originate from differences in the bond strength between atomic hydrogen and the material. With a higher electrocatalytic activity than Ni, Pd catalyst (used as cathode coating) increased TCE removal from 43.5% to 99.8% for Fe, from 56.2% to 79.6% for Cu, from 68.4% to 78.4% for Ni, from 42.0% to 63.6% for Al and from 64.9% to 86.2% for C cathode. The performance of the palladized Fe foam cathode was tested for degradation of TCE in the presence of nitrates, as another commonly found groundwater species. TCE removal decreased from 99% to 41.2% in presence of 100 mg L(-1) of nitrates due to the competition with TCE for HDC at the cathode. The results indicate that the cathode material affects TCE removal rate while the Pd catalyst significantly enhances cathode activity to degrade TCE via HDC.

  5. Nanocellulose as Material Building Block for Energy and Flexible Electronics

    Science.gov (United States)

    Hu, Liangbing

    2014-03-01

    In this talk, I will discuss the fabrications, properties and device applications of functional nanostructured paper based on nanocellulose. Nanostructures with tunable optical, electrical, ionic and mechanical properties will be discussed. Lab-scale demonstration devices, including low-cost Na-ion batteries, microbial fuel cells, solar cells, transparent transistors, actuators and touch screens will be briefly mentioned. These studies show that nanocellulose is a promising green material for electronics and energy devices.

  6. Degradation mechanisms of cable insulation materials during radiation-thermal ageing in radiation environment

    Science.gov (United States)

    Seguchi, Tadao; Tamura, Kiyotoshi; Ohshima, Takeshi; Shimada, Akihiko; Kudoh, Hisaaki

    2011-02-01

    Radiation and thermal degradation of ethylene-propylene rubber (EPR) and crosslinked polyethylene (XLPE) as cable insulation materials were investigated by evaluating tensile properties, gel-fraction, and swelling ratio, as well as by the infrared (FTIR) analysis. The activation energy of thermal oxidative degradation changed over the range 100-120 °C for both EPR and XLPE. This may be attributed to the fact that the content of an antioxidant used as the stabilizer for polymers decreases by evaporation during thermal ageing at high temperatures. The analysis of antioxidant content and oxidative products in XLPE as a model sample showed that a small amount of antioxidant significantly reduced the extent of thermal oxidation, but was not effective for radiation induced oxidation. The changes in mechanical properties were well reflected by the degree of oxidation. A new model of polymer degradation mechanisms was proposed where the degradation does not take place by chain reaction via peroxy radical and hydro-peroxide. The role of the antioxidant in the polymer is the reduction of free radical formation in the initiation step in thermal oxidation, and it could not stop radical reactions for either radiation or thermal oxidation.

  7. Degradation mechanisms of cable insulation materials during radiation-thermal ageing in radiation environment

    Energy Technology Data Exchange (ETDEWEB)

    Seguchi, Tadao, E-mail: seguchi@aj.wakwak.co [Japan Atomic Energy Agency, Tokai 319-1195 (Japan); Tamura, Kiyotoshi; Ohshima, Takeshi; Shimada, Akihiko [Japan Atomic Energy Agency, Tokai 319-1195 (Japan); Kudoh, Hisaaki [University of Tokyo, Tokai 319-1195 (Japan)

    2011-02-15

    Radiation and thermal degradation of ethylene-propylene rubber (EPR) and crosslinked polyethylene (XLPE) as cable insulation materials were investigated by evaluating tensile properties, gel-fraction, and swelling ratio, as well as by the infrared (FTIR) analysis. The activation energy of thermal oxidative degradation changed over the range 100-120 {sup o}C for both EPR and XLPE. This may be attributed to the fact that the content of an antioxidant used as the stabilizer for polymers decreases by evaporation during thermal ageing at high temperatures. The analysis of antioxidant content and oxidative products in XLPE as a model sample showed that a small amount of antioxidant significantly reduced the extent of thermal oxidation, but was not effective for radiation induced oxidation. The changes in mechanical properties were well reflected by the degree of oxidation. A new model of polymer degradation mechanisms was proposed where the degradation does not take place by chain reaction via peroxy radical and hydro-peroxide. The role of the antioxidant in the polymer is the reduction of free radical formation in the initiation step in thermal oxidation, and it could not stop radical reactions for either radiation or thermal oxidation.

  8. Evaluation of desiccated and deformed diaspores from natural building materials

    Directory of Open Access Journals (Sweden)

    Tamás Henn

    2015-03-01

    Full Text Available With the increasing sophistication of paleoethnobotanical methods, it is now possible to reconstruct new aspects of the day-to-day life of past peoples, and, ultimately, gain information about their cultivated plants, land-use practices, architecture, diet, and trade. Reliable identification of plant remains, however, remains essential to the study of paleoethnobotany, and there is still much to learn about precise identification. This paper describes and evaluates the most frequent types of deformed desiccated diaspores revealed from adobe bricks used in buildings in Southwestern Hungary that were built primarily between 1850 and 1950. A total of 24,634 diaspores were recovered from 333.05 kg adobe samples. These seeds and fruits belong to 303 taxa, and the majority were arable and ruderal weed species. A total of 98.97% of the diaspores were identified to species. In other cases, identification was possible only to genus or family (0.93% and 0.10% of diaspores, respectively. Difficulties in identification were caused mainly by morphological changes in the size, shape, color, and surface features of diaspores. Most diaspores were darker in color and significantly smaller than fresh or recently desiccated seeds and fruits. Surface features were often absent or fragmented. The most problematic seeds to identify were those of Centaurea cyanus, Consolida regalis, Scleranthus annuus and Daucus carota ssp. carota, which are discussed in detail. Our research aids archaeobotanists in the identification of desiccated and deformed diaspores.

  9. Estimation of building material moisture using non-invasive TDR sensors

    Science.gov (United States)

    Suchorab, Zbigniew; Sobczuk, Henryk; Łagód, Grzegorz

    2016-07-01

    The article presents the noninvasive attempt to measure moisture of building materials with the use of electric methods. Comparing to the other techniques of moisture detection like chemical or physical, the electric methods enable quick moisture estimation and they seem to be a suitable solution to monitor moisture changes. Most of electric moisture meters are the capacitance and resistance sensors. A perspective technique to determine moisture of building materials and barriers is Time Domain Reflectometry (TDR) method. This method has been successfully applied for moisture determination of the soils and since a few years has been used to measure moisture of building materials. The attempts to measure moisture of building materials require modification of traditional TDR sensor construction and extra calibration procedures. Sensors applied for building materials, comparing to the traditional ones are noninvasive. The advantages of surface sensors proposed in this article are the following: no influence on material structure, easier sample preparation for laboratory measurements, good possibility to apply for in-situ measurements. Major disadvantage of the described sensors is the difficulty of outgoing sensor signal interpretation and thus the possibility of the increase of measurement uncertainty. Anyhow it must be underlined that proposed in the article sensor constructions seem to be a balanced alternative for quick moisture detection.

  10. Electrokinetic salt removal from porous building materials using ion exchange membranes

    NARCIS (Netherlands)

    Kamran, K.; Van Soestbergen, M.; Pel, L.

    The removal of salt from porous building materials under the influence of an applied voltage gradient normally results in high pH gradients due to the formation of protons and hydroxyl ions at the electrodes. The formed acidic and alkaline regions not only lead to disintegration of the porous materi

  11. Investigation of the actual conditions of asbestos use in school building materials

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Y.C.; Son, B.H.; Hong, W.H. [Kyungpook National Univ., Daegu (Korea, Republic of)

    2008-07-01

    Asbestos has been widely used as a construction material due to its high insulation properties, abrasion resistance, and tensile strength. This paper evaluated materials containing asbestos in school buildings in Korea constructed between the 1970s and the 1990s. Interviews with building manager were used in addition to data obtained from building drawings and building registers. The study showed that asbestos was used to form slates, ceiling materials, interior wall materials, and outer-wall materials. Eighty per cent of the asbestos used in Korea was imported. Asbestos amounts were calculated by multiplying the area of construction materials used by the unit weight per m{sup 2} of the asbestos-containing materials, and again by asbestos content. The document survey was not successful in identifying asbestos in all construction materials. A field survey was then conducted in order to collect samples which were then analyzed at a laboratory. Results of the study will be used to plan asbestos control and removal procedures. 11 refs., 5 tabs., 4 figs.

  12. Emissivity measurements on historic building materials using dual-wavelength infrared thermography

    Science.gov (United States)

    Moropoulou, Antonia; Avdelidis, Nicolas P.

    2001-03-01

    The most reliable method to obtain correct emissivity values for the infrared thermographic systems and applications is to determine the emissivity of the targets to be tested. Although this approach is not possible during in situ applications, samples of the targets can be collected and measured, as in this work, in the laboratory. In the present work, the emissivity values of selected historic building materials were measured at a variety of temperatures, in the 3-5.4 micrometers and 8-12 micrometers regions of the infrared spectrum. Porous stones from the Mediterranean area and marbles, used as historic building materials, were investigated. The examined materials presented different emissivity values, caused by their surface state and microstructure. In addition, the effect of temperature and wavelength on the emissivity values of such historic building materials was also considered.

  13. Exposure to radiation from the natural radioactivity in Tunisian building materials.

    Science.gov (United States)

    Gharbi, F; Oueslati, M; Abdelli, W; Samaali, M; Ben Tekaya, M

    2012-12-01

    Building materials can expose public and workers to radiation because of their content of radium, thorium and potassium isotopes. This is why it is very important from the radiological point of view to survey the natural radioactivity content of commonly used building materials in any country. This work consists of the measurement of (226)Ra, (232)Th and (40)K activity concentrations in a variety of commonly used building materials in Tunisia and on the estimation of their radiological hazard. The maximum value of radium equivalent for the studied materials was equal to 169 Bq kg(-1) and corresponds to the clay brick, which is lower than the recommended value of 370 Bq kg(-1). In this work, several radiological indexes were calculated and were found to be under their highest permitted limit.

  14. Materials for aesthetic, energy-efficient, and self-diagnostic buildings.

    Science.gov (United States)

    Fernández, John E

    2007-03-30

    It has become desirable to reduce the nonrenewable content and energy footprint of the built environment and to develop "smart buildings" that allow for inexpensive monitoring and self-diagnostic capabilities. Latest-generation embedded sensors, self-healing composites, and nanoscale and responsive materials may augur a time when buildings can substantially adjust to changing environmental and functional demands. However, faced with the legal liability resulting from unknown lifetime performance, designers and engineers have had little incentive to incorporate new material technologies into building designs. As efficiency issues become more acute, the potential for improvement in performance from new materials, together with partnerships between the materials science community and those entrusted with the design and engineering of the built environment, may offer real breakthroughs for the future.

  15. Effect of Moisture Content on Thermal Properties of Porous Building Materials

    Science.gov (United States)

    Kočí, Václav; Vejmelková, Eva; Čáchová, Monika; Koňáková, Dana; Keppert, Martin; Maděra, Jiří; Černý, Robert

    2017-02-01

    The thermal conductivity and specific heat capacity of characteristic types of porous building materials are determined in the whole range of moisture content from dry to fully water-saturated state. A transient pulse technique is used in the experiments, in order to avoid the influence of moisture transport on measured data. The investigated specimens include cement composites, ceramics, plasters, and thermal insulation boards. The effect of moisture-induced changes in thermal conductivity and specific heat capacity on the energy performance of selected building envelopes containing the studied materials is then analyzed using computational modeling of coupled heat and moisture transport. The results show an increased moisture content as a substantial negative factor affecting both thermal properties of materials and energy balance of envelopes, which underlines the necessity to use moisture-dependent thermal parameters of building materials in energy-related calculations.

  16. Dose rate effects in radiation degradation of polymer-based cable materials

    Science.gov (United States)

    Plaček, V.; Bartoníček, B.; Hnát, V.; Otáhal, B.

    2003-08-01

    Cable ageing under the nuclear power plant (NPP) conditions must be effectively managed to ensure that the required plant safety and reliability are maintained throughout the plant service life. Ionizing radiation is one of the main stressors causing age-related degradation of polymer-based cable materials in air. For a given absorbed dose, radiation-induced damage to a polymer in air environment usually depends on the dose rate of the exposure. In this work, the effect of dose rate on the degradation rate has been studied. Three types of NPP cables (with jacket/insulation combinations PVC/PVC, PVC/PE, XPE/XPE) were irradiated at room temperature using 60Co gamma ray source at average dose rates of 7, 30 and 100 Gy/h with the doses up to 590 kGy. The irradiated samples have been tested for their mechanical properties, thermo-oxidative stability (using differential scanning calorimetry, DSC), and density. In the case of PVC and PE samples, the tested properties have shown evident dose rate effects, while the XPE material has shown no noticeable ones. The values of elongation at break and the thermo-oxidative stability decrease with the advanced degradation, density tends to increase with the absorbed dose. For XPE samples this effect can be partially explained by the increase of crystallinity. It was tested by the DSC determination of the crystalline phase amount.

  17. Simple hydrazone building blocks for complicated functional materials.

    Science.gov (United States)

    Tatum, Luke A; Su, Xin; Aprahamian, Ivan

    2014-07-15

    CONSPECTUS: The ability to selectively and effectively control various molecular processes via specific stimuli is a hallmark of the complexity of biological systems. The development of synthetic structures that can mimic such processes, even on the fundamental level, is one of the main goals of supramolecular chemistry. Having this in mind, there has been a foray of research in the past two decades aimed at developing molecular architectures, whose properties can be modulated using external inputs. In most cases, reversible conformational, configurational, or translational motions, as well as bond formation or cleavage reactions have been used in such modulations, which are usually initiated using inputs including, irradiation, metalation, or changes in pH. This research activity has led to the development of a diverse array of impressive adaptive systems that have been used in showcasing the potential of molecular switches and machines. That being said, there are still numerous obstacles to be tackled in the field, ranging from difficulties in getting molecular switches to communicate and work together to complications in integrating and interfacing them with surfaces and bulk materials. Addressing these challenges will necessitate the development of creative new approaches in the field, the improvement of the currently available materials, and the discovery of new molecular switches. This Account will describe how our quest to design new molecular switches has led us to the development of structurally simple systems that can be used for complicated functions. Our focus on the modular and tunable hydrazone functional group was instigated by the desire to simplify the structure and design of molecular switches in order to circumvent multistep synthesis. We hypothesized that by avoiding this synthetic bottleneck, which is one of the factors that hinder fast progress in the field, we can expedite the development and deployment of our adaptive materials. It should be

  18. Polyhedral Boranes: A Versatile Building Block for Nanoporous Materials

    Science.gov (United States)

    Clingerman, Daniel Jon

    The studies described in this dissertation examine several new concepts related to polyhedral boranes and their applications towards the synthesis of novel nanoporous materials. The unique thermal and chemical robustness, rigidity, quasi-spherical geometry, and high boron content of polyhedral boranes are explored to generate materials not possible with typical organic synthons. Aside from the fundamental synthetic work, this work was also aimed at solving larger global issues such as energy storage and new routes to therapeutics. Chapter 2 highlights the discovery of the first highly porous carborane-based metal-organic framework, where the spherical nature of the carborane increases volumetric surface area without reducing pore volume. Chapter 3 examines the first tritopic carborane-based ligand and the stabilizing effect the rigid, sterically bulky carboranyl groups have on highly porous topologies not stable with typical organic ligands. Chapters 4 and 5 describe the use of polyhedral borane-based ligands as a means to influence and generate unexpected topologies. Lastly, chapter 6 explores using a simple carborane-based ligand that harnesses the power of coordination-driven assembly to rapidly generate a high boron-containing supramolecular cuboctahedron.

  19. The influence of surface treatment on mass transfer between air and building material

    DEFF Research Database (Denmark)

    Kwiatkowski, Jerzy; Rode, Carsten; Hansen, Kurt Kielsgaard

    2008-01-01

    The processes of mass transfer between air and building structure and in the material influence not only the conditions within the material but also inside the connected air spaces. The material which absorbs and desorbs water vapour can be used to moderate the amplitude of indoor relative humidity...... and therefore to participate in the improvement of the indoor air quality and energy saving. Many parameters influence water vapour exchange between indoor air and building material. The aim of this work is to present the change of mass transfer under different climatic and material conditions. The measurements...... for the experiments: gypsum board and calcium silicate. The wallpaper and paint were used as finishing materials. Impact of the following parameters for changes of RH was studied: coating, temperature and air movement. The measurements showed that acryl paint (diffusion open) can significantly decrease mass uptake...

  20. Bacillus megaterium mediated mineralization of calcium carbonate as biogenic surface treatment of green building materials.

    Science.gov (United States)

    Dhami, Navdeep Kaur; Reddy, M Sudhakara; Mukherjee, Abhijit

    2013-12-01

    Microbially induced calcium carbonate precipitation is a biomineralization process that has various applications in remediation and restoration of range of building materials. In the present study, calcifying bacteria, Bacillus megaterium SS3 isolated from calcareous soil was applied as biosealant to enhance the durability of low energy, green building materials (soil-cement blocks). This bacterial isolate produced high amounts of urease, carbonic anhydrase, extra polymeric substances and biofilm. The calcium carbonate polymorphs produced by B. megaterium SS3 were analyzed by scanning electron microscopy, confocal laser scanning microscopy, X-ray diffraction and Fourier transmission infra red spectroscopy. These results suggested that calcite is the most predominant carbonate formed by this bacteria followed by vaterite. Application of B. megaterium SS3 as biogenic surface treatment led to 40 % decrease in water absorption, 31 % decrease in porosity and 18 % increase in compressive strength of low energy building materials. From the present investigation, it is clear that surface treatment of building materials by B. megaterium SS3 is very effective and eco friendly way of biodeposition of coherent carbonates that enhances the durability of building materials.

  1. Verification of some building materials as gamma-ray shields.

    Science.gov (United States)

    Mann, Kulwinder Singh; Singla, Jyoti; Kumar, Vipan; Sidhu, G S

    2012-08-01

    The shielding properties for gamma rays of a few low Z materials were investigated. The values of the mass attenuation coefficient, equivalent atomic number, effective atomic number, exposure buildup factor and energy absorption buildup factor were calculated and used to estimate the shielding effectiveness of the samples under investigation. It has been observed that the shielding effectiveness of a sample is directly related to its effective atomic number. The shielding character of any sample is a function of the incident photon energy. Good shielding behaviour has been verified in soil samples in the photon energy region of 0.015-0.30 MeV and of dolomite in 3-15 MeV. The results have been shown graphically with more useful conclusions.

  2. The Effect of Mechanical Load on the Thermal Conductivity of Building Materials

    Directory of Open Access Journals (Sweden)

    J. Toman

    2000-01-01

    Full Text Available The effect of mechanical load on the thermal conductivity of building materials in the design of envelope parts of building structures is studied. A typical building material is chosen in the practical investigation of this effect, namely the cement mortar. It is concluded that in the range of hygroscopic moisture content, lower levels of mechanical load, typically up to 90 % of compressive strength (CS, are not dangerous from the point of view of worsening the designed thermal properties, but in the overhygroscopic region, the load as low as 57 % of CS may be dangerous. The higher levels of loading are found to be always significant because they lead to marked increase of thermal conductivity which is always a negative information for a building designer.

  3. Thermal Performance of Typical Residential Building in Karachi with Different Materials for Construction

    Directory of Open Access Journals (Sweden)

    Nafeesa Shaheen

    2016-04-01

    Full Text Available This research work deals with a study of a residential building located in climatic context of Karachi with the objective of being the study of thermal performance based upon passive design techniques. The study helps in reducing the electricity consumption by improving indoor temperatures. The existing residential buildings in Karachi were studied with reference to their planning and design, analyzed and evaluated. Different construction?s compositions of buildings were identified, surveyed and analyzed in making of the effective building envelops. Autodesk® Ecotect, 2011 was used to determine indoor comfort conditions and HVAC (Heating, Ventilation, Air-Conditioning and Cooling loads. The result of the research depicted significant energy savings of 38.5% in HVAC loads with proposed building envelop of locally available materials and glazing.

  4. Monitoring moisture movements in building materials using x-ray attenuation

    DEFF Research Database (Denmark)

    Pease, Bradley Justin; Scheffler, Gregor A.; Janssen, Hans

    2012-01-01

    X-ray attenuation measurements are commonly used as a non-destructive method to monitor internal concentration changes of moisture (i.e., moisture content) and other chemical compounds in porous building materials. The technique provides direct measurements of moisture content changes through ana...... autoclaved concrete, clay brick, cementitious materials, and wood. Results from the parametric investigation indicate the attenuation coefficient of water is dependent on the type and thickness of the porous material....

  5. Research on phase-change material building mass applied in the air-conditioning field

    Institute of Scientific and Technical Information of China (English)

    YANQuanying

    2003-01-01

    Phase-change material building mass contains phase-change matenals. It can decrease air-conditioning load and indoor temperature fluctuations, and improve comfort degree in summer because of thermal storage property of phase-change material. Thereby, the scale, initial investment and operational cost of air-conditioning system decrease effectively. The indoor surroundings improve. In this paper, suitable phase-change material used in architecture and combination mode between phase change material and architectural material were studied. By considering the properties of materials, such as phase-change temperature, phase-change latent heat, thermal conductivity and expansion coefficient, phase-change materials were selected and evaluated. Combination mode between phase-change material and architectural material were provided. The influence of phase-change material structure on thermal performance in room and energy-saving effect were analyzed and compared with traditional structure without phase-change material. It is proved that phase-change material structure is feasible in the practical engineenng. These provide the basis for developing phase-change material building mass.

  6. Analysis of surface degradation of high density polyethylene (HDPE) insulation material due to tracking

    Indian Academy of Sciences (India)

    R Sarathi; S Chandrasekar; V Sabari Giri; C Venkataseshaiah; R Velmurugan

    2004-06-01

    In the present work, tracking phenomena has been studied with HDPE material under a.c. voltage, with ammonium chloride as the contaminant. It is noticed that the tracking time depends on the conductivity and flow rate of the contaminant. The diffusion coefficient of the material was obtained. The thermal and chemical stability of the material were identified by carrying out a methodical experimental study. The physico-chemical analyses viz. wide angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA), were carried out and it was concluded that the mechanism of tracking process is due to the surface degradation. The surface condition of the insulation structure was characterized for any surface discharges or tracking, using the leakage current measurement, utilizing the wavelet concepts.

  7. Relation of historical quarrying, material utilization and performance on buildings in Eastern Finland

    Science.gov (United States)

    Luodes, Nike M.; Pirinen, Heikki

    2016-04-01

    Finland might seem to have lower stone heritage compared to other southern European countries, but it has been the main exporter of dimension stone to the majestic buildings that made St.Petersburg a recognized cultural heritage. In Finland, though, the stone seems undervalued. The only dramatic and predominant stone buildings are those of agencies and administrations located in the towns, where the stone has been used to impress and symbolize value. Romantic style used massive bossy stone in building's full height and created fine traditional carvings. Otherwise the communities have mainly built settlements in contact with the nature, with materials easily available and of low cost, following architectonical trends of the periods and producing interesting stone details. During the past years, research has been conducted on historical buildings interconnecting scientific and artistic approach to evaluate material durability and cultural relevance of the artifacts. Generally until mid 20th century the stone has been traditionally used massive for basements and walls. The materials still present good mechanical characteristics and most often the weathering level after hundreds of years of exposure had reached only the first millimeters from the curst. Instead the old methodology for deposit exploitation has left visible signs on the buildings. Some examples are visible from Kuopio. The exploitation of small, easy-to-reach surface deposits, even if planned by local experts, has affected quality and appearance of historical buildings. As an example the excavation of shallow quarries where also weathered crop was kept as a product has characterized the basement of the Niirala school that presents change in colors due to original material more than to weathering on site. Fissuring is also visible on a couple of blocks while marks on the rocks depict the old excavation method. Most often the deposits had been in the vicinities, frequently hidden by further construction

  8. Materials degradation in fission reactors: Lessons learned of relevance to fusion reactor systems

    Science.gov (United States)

    Was, Gary S.

    2007-08-01

    The management of materials in power reactor systems has become a critically important activity in assuring the safe, reliable and economical operation of these facilities. Over the years, the commercial nuclear power reactor industry has faced numerous 'surprises' and unexpected occurrences in materials. Mitigation strategies have sometimes solved one problem at the expense of creating another. Other problems have been solved successfully and have motivated the development of techniques to foresee problems before they occur. This paper focuses on three aspects of fission reactor experience that may benefit future fusion systems. The first is identification of parameters and processes that have had a large impact on the behavior of materials in fission systems such as temperature, dose rate, surface condition, gradients, metallurgical variability and effects of the environment. The second is the development of materials performance and failure models to provide a basis for assuring component integrity. Last is the development of proactive materials management programs that identify and pre-empt degradation processes before they can become problems. These aspects of LWR experience along with the growing experience with materials in the more demanding advanced fission reactor systems form the basis for a set of 'lessons learned' to aid in the successful management of materials in fusion reactor systems.

  9. Occurrence, degradation, and effect of polymer-based materials in the environment.

    Science.gov (United States)

    Lambert, Scott; Sinclair, Chris; Boxall, Alistair

    2014-01-01

    There is now a plethora of polymer-based materials (PBMs) on the market, because of the increasing demand for cheaper consumable goods, and light-weight industrial materials. Each PBM constitutes a mixture of their representative polymer/sand their various chemical additives. The major polymer types are polyethylene, polypropylene,and polyvinyl chloride, with natural rubber and biodegradable polymers becoming increasingly more important. The most important additives are those that are biologically active, because to be effective such chemicals often have properties that make them resistant to photo-degradation and biodegradation. During their lifecycle,PBMs can be released into the environment form a variety of sources. The principal introduction routes being general littering, dumping of unwanted waste materials,migration from landfills and emission during refuse collection. Once in the environment,PBMs are primarily broken down by photo-degradation processes, but due to the complex chemical makeup of PBMs, receiving environments are potentially exposed to a mixture of macro-, meso-, and micro-size polymer fragments, leached additives, and subsequent degradation products. In environments where sunlight is absent (i.e., soils and the deep sea) degradation for most PBMs is minimal .The majority of literature to date that has addressed the environmental contamination or disposition of PBMs has focused on the marine environment. This is because the oceans are identified as the major sink for macro PBMs, where they are known to present a hazard to wildlife via entanglement and ingestion. The published literature has established the occurrence of microplastics in marine environment and beach sediments, but is inadequate as regards contamination of soils and freshwater sediments. The uptake of microplastics for a limited range of aquatic organisms has also been established, but there is a lack of information regarding soil organisms, and the long-term effects of

  10. CONTRIBUTION TO THE POTENTIAL OF USING FRP MATERIALS IN THE REHABILITATION AND STABILIZATION OF TIMBERED BUILDINGS

    Directory of Open Access Journals (Sweden)

    Tomáš Čejka

    2015-12-01

    Full Text Available Wooden log, timbered perimeter and interior walls ranked among the most common building constructions used from the Early Middle Ages. In most cases, the local natural resources, i.e. wood, clay, straw and stone, were used for building houses with wooden framing. This article outlines typical defects and failures of timbered houses, “classic” techniques for the rehabilitation of these defects and failures indicating the potential of using composite materials based on high- strength fibres and epoxy resin in the rehabilitation and strengthening of timbered buildings.

  11. Source strength of fungal spore aerosolization from moldy building material

    Energy Technology Data Exchange (ETDEWEB)

    Gorny, Rafa L.; Reponen, Tiina; Grinshpun, Sergey A.; Willeke, Klaus [Cincinnati Univ., Dept. of Environmental Health, Cincinnati, OH (United States)

    2001-07-01

    The release of Aspergillus versicolor, Cladosporium cladosporioides, and Penicillium melinii spores from agar and ceiling tile surfaces was tested under different controlled environmental conditions using a newly designed and constructed aerosolization chamber. This study revealed that all the investigated parameters, such as fungal species, air velocity above the surface, texture of the surface, and vibration of contaminated material, affected the fungal spore release. It was found that typical indoor air currents can release up to 200 spores cm {sup -2} from surface with fungal spores during 30-min experiments. The release of fungal spores from smooth agar surfaces was found to be inadequate for accurately predicting the emission from rough ceiling tile surfaces because the air turbulence increases the spore release from a rough surface. A vibration of a frequency of 1Hz at a power level of 14W resulted in a significant increase in the spore release rate. The release appears to depend on the morphology of the fungal colonies grown on ceiling tile surfaces including the thickness of conidiophores, the length of spore chains, and the shape of spores. The spores were found to be released continuously during each 30-min experiment. However, the release rate was usually highest during the first few minutes of exposure to air currents and mechanical vibration. About 71-88% of the spores released during a 30-min interval became airborne during the first 10min. (Author)

  12. Free-cooling of buildings with phase change materials

    Energy Technology Data Exchange (ETDEWEB)

    Zalba, B.; Marin, J.M. [Universidad de Zaragoza Maria de Luna (Spain). Departamento de Ingenieria Mecanica; Cabeza, L.F. [Universitat de Lleida (Spain). Departamento d' Informatica i Eng. Industrial; Mehling, H. [ZAE Bayern, Abt. 1 Energy Conversion and Storage, Garching (Germany)

    2004-12-01

    In this paper, the application of phase change materials (PCM) in free-cooling systems is studied. Free-cooling is understood as a means to store outdoors coolness during the night, to supply indoors cooling during the day. The use of PCMs is suitable because of the small temperature difference between day indoors and night outdoors. An installation that allows testing the performance of PCMs in such systems was designed and constructed. The main influence parameters like ratio of energy/volume in the encapsulates, load/unload rate of the storage, and cost of the installation were determined, and experiments were performed following the design of experiments strategy. The statistical analysis showed that the effects with significant influence in the solidification process are the thickness of the encapsulation, the inlet temperature of the air, the air flow, and the interaction thickness x temperature. For the melting process the same holds, but the inlet air temperature had a higher influence than the thickness of the encapsulation. With the empirical model developed in this work, a real free-cooling system was designed and economically evaluated. (author)

  13. Monitoring Low-Cycle Fatigue Material-Degradation by Ultrasonic Methods

    Directory of Open Access Journals (Sweden)

    R. Himawan

    2010-08-01

    Full Text Available Any system consisting of structural material often undergoes fatigue, which is caused by dynamic load cycle. As a structural system, nuclear power plant is very likely to have low-cycle fatigue at many of its components. Taking into account the importance of monitoring low-cycle fatigue on structural components to prevent them from getting failure, the authors have conducted a work to monitor material degradation caused by low-cycle fatigue by using ultrasonic method. An alloy of Cu-40Zn was used as a test specimen. Ultrasonic water immersion procedure was employed in this ultrasonic test. The probe used is a focusing type and has frequency as high as 15 MHz. The specimen area tested is in the middle part divided into 14 points × 23 points. The results, which were frequency spectrums, were analyzed using two parameters: frequency spectrum peak intensity and attenuation function gradient. The analysis indicates that peak intensity increases at the beginning of load cycle and then decreases. Meanwhile, gradient of attenuation function is lower at the beginning of fatigue process, and then consistently gets higher. It concludes that low-fatigue material degradation can be monitored by using ultrasonic method.

  14. Low-cost NORM concentrations measuring technique for building materials of Uzbekistan

    Science.gov (United States)

    Safarov, Akmal; Safarov, Askar; Azimov, Askarali; Darby, Iain G.

    2016-04-01

    Concentrations of natural radionuclides of building materials are important in order to estimate exposure of humans to radiation, who can spend up to 80% of their time indoors. One of the indicators of building materials' safety is the radium equivalent activity, which is regulated by national and international normative documents [1,2,3]. Materials with Ra(eq) =ageing. Long measurement times including ageing of samples are major constraints for performing large number of analyses [6]. Typically ageing of samples and analysis is 40 days. Gamma-spectrometric analysis of brick, crushed stone, red sand, granite, white marble and concrete cubes was performed both before and after ageing of samples (10, 20, 30 and 40 days). Measurement times of samples were 1, 3, 6 and 12 hours. Samples were measured in 1 liter Marinelli beaker geometry, using NaI(Tl) spectrometers with crystal sizes 2.5 x 2.5 in and 3.1 x 3.1 in. Efficiency calibration of spectrometers was done using certified volumetric (1 liter Marinelli beaker) Ra-226, Th-232 and K-40 sources filled with silica sand and density 1,7 kg/l. Herein we present results indicating that one hour measuring may be sufficient for samples in 1 liter Marinelli beakers offering prospect of significant time and cost improvements. References: 1. NEA-OECD (1979): Exposure to radiation from natural radioactivity in building materials. Report by Group of Experts of the OECD Nuclear Energy Agency (NEA) Paris 2. STUK (Radiation and Nuclear Safety Authority) (2003): The radioactivity of building materials and ash. Regulatory Guides on Radiation Safety (ST Guides) ST 12.2 (Finland) (8 October 2003) 3. GOST 30108-94 (1995): Building materials and elements. Determination of specific activity of natural radioactive nuclei. Interstate Standard. 4. Krisiuk E.M. et al., (1971). A study on Radioactivity in Building Materials (Leningrad: Research Institute for radiation Hygiene) 5. Beretka, J., & Mathew, P. J. (1985). Natural radioactivity of

  15. Innovative Development of Building Materials Industry of the Region Based on the Cluster Approach

    Directory of Open Access Journals (Sweden)

    Mottaeva Asiiat

    2016-01-01

    Full Text Available The article discusses issues of innovative development of building materials industry of the region based on the cluster approach. Determined the significance of regional cluster development of the industry of construction materials as the effective implementation of the innovative breakthrough of the region as an important part of strategies for strengthening innovation activities may be to support the formation and development of cluster structures. Analyses the current situation with innovation in the building materials industry of the region based on the cluster approach. In the course of the study revealed a direct correlation between involvement in innovative activities on a cluster basis, and the level of development of industry of construction materials. The conducted research allowed identifying the factors that determine the innovation process, systematization and classification which determine the sustainable functioning of the building materials industry in the period of active innovation. The proposed grouping of innovations for the construction industry taking into account industry-specific characteristics that reflect modern trends of scientific and technological progress in construction. Significance of the study lies in the fact that the proposals and practical recommendations can be used in the formation mechanism of innovative development of building materials industry and the overall regional construction complex of Russian regions by creating clusters of construction.

  16. The Effect of Anisotropy of Building Materials on the Moisture Transfer

    Directory of Open Access Journals (Sweden)

    J. Drchalová

    2000-01-01

    Full Text Available The effect of anisotropy of building materials on the moisture transfer in the design of envelope parts of building structures is studied. Two typical fibre containing plate building materials produced in the Czech Republic, Dekalux and Dekalit P, are chosen for the demonstration of this effect. Experimental results show that while for lighter Dekalit P, an order of magnitude difference in the moisture diffusivities k for the two basic orientations, i.e. along and across the plate, is observed, for the heavier Dekalux the differences in k are within the errorbar of the experimental method. As follows from the experimental results, compacting of surface layers of the plates of light fibred materials is very favorable from the point of view of moisture penetration but one should keep in mind that any local damage of the surface layer can result in a considerably faster moisture transfer in the direction along the plate.

  17. Experimental study of passive cooling of building facade using phase change materials to increase thermal comfort in buildings in hot humid areas

    Directory of Open Access Journals (Sweden)

    A. A. Madhumathi, B. M.C. Sundarraja

    2012-01-01

    Full Text Available Storage of cooler night temperatures using Phase Change Material (PCM energy storage technique, for cooling of ambient air during hot day times can be an alternate of current cooling techniques in building sector. This work presents the results of an experimental set-up to test energy saving potential of phase change materials with typical construction materials in building facade in Hot-Humid Climatic Regions in real conditions. The main objective of this research is to demonstrate experimentally that it is possible to improve the thermal comfort and reduce the energy consumption of a building without substantial increase in the weight of the construction materials with the inclusion of PCM. This research was conducted to study and evaluate the performance of the existing materials integrated with Organic PCM Polyethylene glycol (PEG E600. This research suggested that the heat gain is significantly reduced when the PCM is incorporated into the brick (conventional building material.

  18. Cleaner phosphogypsum, coal combustion ashes and waste incineration ashes for application in building materials: A review

    Energy Technology Data Exchange (ETDEWEB)

    L. Reijnders [University of Amsterdam, Amsterdam (Netherlands)

    2007-02-15

    Application of phosphogypsum, coal combustion ashes and waste incineration ashes in building materials has been limited by the presence of minor components that are hazardous, such as radioactive substances, chlorinated dioxins and heavy metals, or have a negative impact on product quality or production economics, such as phosphate, fluoride, carbon and chloride. Source reduction, destruction of persistent organics and separation techniques may reduce the concentrations of such components. With a few exceptions, separation techniques currently lead to significantly higher (private) costs. Higher waste disposal costs, tighter regulations and higher prices for competing virgin minerals could make the use of the purified phosphogypsum and ashes in building materials more attractive.

  19. Characterization of Environmental Impact of Building Materials for the Purpose of Ecodesign

    Science.gov (United States)

    Skele, Agnese; Repele, Mara; Bazbauers, Gatis

    2011-01-01

    -The building material manufacturing sector is one of the sectors with the highest consumption of fossil fuel resources. The "cradle-to-gate" study of the ceramic bricks made in the Āne plant of JSC Lode, Latvia, is performed according to ISO standards 14044:2006. Life cycle inventory data have been collected at the factory site. Three different perspectives of the "Eco-Indicator'99" method are used to conduct an environmental characterization of the building materials to obtain the total impact indicator.

  20. Assessment of natural radioactivity and radiological hazards in building materials used in Yan'an, China.

    Science.gov (United States)

    Lu, Xinwei; Li, Nan; Yang, Guang; Zhao, Caifeng

    2013-03-01

    The concentration of natural radionuclides in commonly used building materials collected from Yan'an, China, was determined using gamma ray spectroscopy with a NaI(Tl) detector. The activity concentration of ²²⁶Ra, ²³²Th, and ⁴⁰K in the studied building materials ranges from 9.4-73.1, 11.5-86.9, and 258.9-1,055.1 Bq kg⁻¹, respectively. The concentrations for these natural radionuclides were compared with the reported data of other countries and the world mean values for soil. The radium equivalent activity (Raeq), external hazard index (Hex), internal hazard index (Hin), indoor air absorbed dose rate, and annual effective dose rate due to natural radionuclides in samples were estimated to assess radiological hazards for people living in dwellings made of the studied building materials. The calculated Raeq values of all building materials (75.7-222.1 Bq kg⁻¹) are lower than the limit of 370 Bq kg⁻¹. The values of Hex and Hin are less than unity. The mean values of indoor air absorbed dose rates of all building materials (101.0 ± 14.1-177.0 ± 6.8 nGy h⁻¹) are higher than the world population-weighted average of 84 nGy h⁻¹, while the mean values of annual effective dose range from 0.50 ± 0.07-0.87 ± 0.03 mSv y⁻¹, which are lower than the recommended limit of 1 mSv y⁻¹. It is found that these materials may be used safely as construction materials and do not pose significant radiation hazards to inhabitants.

  1. Screening for perfluoroalkyl acids in consumer products, building materials and wastes.

    Science.gov (United States)

    Bečanová, Jitka; Melymuk, Lisa; Vojta, Šimon; Komprdová, Klára; Klánová, Jana

    2016-12-01

    Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are a large group of important chemical compounds with unique and useful physico-chemical properties, widely produced and used in many applications. However, due to the toxicity, bioaccumulation and long-range transport potential of certain PFASs, they are of significant concern to scientists and policy makers. To assess human exposure to PFASs, it is necessary to understand the concentrations of these emerging contaminants in our environment, and particularly environments where urban population spend most of their time, i.e. buildings and vehicles. A total of 126 samples of building materials, consumer products, car interior materials and wastes were therefore analyzed for their content of key PFASs - 15 perfluoroalkyl acids (PFAAs). At least one of the target PFAAs was detected in 88% of all samples. The highest concentration of Σ15PFAAs was found in textile materials (77.61 μg kg(-1)), as expected, since specific PFAAs are known to be used for textile treatment during processing. Surprisingly, PFAAs were also detected in all analyzed composite wood building materials, which were dominated by perfluoroalkyl carboxylic acids with 5-8 carbons in the chain (Σ4PFCAs up to 32.9 μg kg(-1)). These materials are currently widely used for building refurbishment, and this is the first study to find evidence of the presence of specific PFASs in composite wood materials. Thus, in addition to consumer products treated with PFASs, materials used in the construction of houses, schools and office buildings may also play an important role in human exposure to PFASs.

  2. Assessment of natural radioactivity in major building materials of Xiangyang, China

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Tingting; Lu, Xinwei [Shaanxi Normal Univ., Xi' an (China). School of Tourism and Environment

    2014-10-01

    The activity concentrations of {sup 40}K, {sup 226}Ra and {sup 232}Th in the commonly used building materials collected from Xiangyang were measured using NaI (Tl) gamma spectrometer. The radioactivity values of {sup 40}K, {sup 226}Ra and {sup 232}Th in the studied samples ranged from 130.5 to 1006.3, 8.4 to 164.0, and 8.7 to 145.6 Bq kg{sup -1}, respectively. The concentrations of these radionuclides have been compared with the typical published world values. Radium equivalent activity, external and internal hazard indexes, external and internal exposure indexes, indoor air absorbed dose rate and annual effective dose rate have been calculated to assess the potential radiological hazard associated with natural radionuclides in the studied materials. The calculated values of all the assessed indices in the analyzed building materials except for fly ash are below the internationally accepted limits indicating that these building materials can be safely used in dwellings construction and do not lead to any significant radiation exposure to occupants. Nevertheless, the annual effective dose rate values of all fly ash samples, external and internal hazard indexes values in most fly ash samples exceed the recommended values. It is, therefore, desirable to regularly monitor the natural radioactivity level of the building materials products made from fly ash.

  3. Selecting Materials for Environmental-Friendly Buildings: The Need for Improved Environmental Impact Data

    Directory of Open Access Journals (Sweden)

    Nachawit T.

    2012-01-01

    Full Text Available Buildings of the future need to be more environmental-friendly. Selecting environmentally-benign materials in design stage would partly help achieving such goal. Examination of existing environmental impact data of building materials reveals that the data differ greatly from one source to another. Comparisons of environmental impact values of selected materials are presented. The sources that give rise to data variation are identified and discussed. The applicability of existing data is assessed from the designers’ perspective. Limitations of current practice in data acquisition and presentation are also discussed. It is concluded that existing environmental impact data of building materials are inconsistent and perplexing to designers. An alternative approach to data acquisition and presentation is to break the life cycle of building materials into several phases and to calculate the total impact value as the sum of the impacts of all phases. This would make the determination of the full life cycle value feasible and increase external validity of research results.

  4. Microfungal contamination of damp buildings--examples of risk constructions and risk materials.

    Science.gov (United States)

    Gravesen, S; Nielsen, P A; Iversen, R; Nielsen, K F

    1999-06-01

    To elucidate problems with microfungal infestation in indoor environments, a multidisciplinary collaborative pilot study, supported by a grant from the Danish Ministry of Housing and Urban Affairs, was performed on 72 mold-infected building materials from 23 buildings. Water leakage through roofs, rising damp, and defective plumbing installations were the main reasons for water damage with subsequent infestation of molds. From a score system assessing the bioavailability of the building materials, products most vulnerable to mold attacks were water damaged, aged organic materials containing cellulose, such as wooden materials, jute, wallpaper, and cardboard. The microfungal genera most frequently encountered were Penicillium (68%), Aspergillus (56%), Chaetomium (22%), Ulocladium, (21%), Stachybotrys (19%) and Cladosporium (15%). Penicillium chrysogenum, Aspergillus versicolor, and Stachybotrys chartarum were the most frequently occurring species. Under field conditions, several trichothecenes were detected in each of three commonly used building materials, heavily contaminated with S. chartarum. Under experimental conditions, four out of five isolates of S. chartarum produced satratoxin H and G when growing on new and old, very humid gypsum boards. A. versicolor produced the carcinogenic mycotoxin sterigmatocystin and 5-methoxysterigmatocystin under the same conditions.

  5. Asbestos-containing materials and airborne asbestos levels in industrial buildings in Korea.

    Science.gov (United States)

    Choi, Sangjun; Suk, Mee-Hee; Paik, Nam Won

    2010-03-01

    Recently in Korea, the treatment of asbestos-containing materials (ACM) in building has emerged as one of the most important environmental health issues. This study was conducted to identify the distribution and characteristics of ACM and airborne asbestos concentrations in industrial buildings in Korea. A total of 1285 presumed asbestos-containing material (PACM) samples were collected from 80 workplaces across the nation, and 40% of the PACMs contained more than 1% of asbestos. Overall, 94% of the surveyed workplaces contained ACM. The distribution of ACM did not show a significant difference by region, employment size, or industry. The total ACM area in the buildings surveyed was 436,710 m2. Ceiling tile ACM accounted for 61% (267,093 m2) of the total ACM area, followed by roof ACM (32%), surfacing ACM (6.1%), and thermal system insulation (TSI). In terms of asbestos type, 98% of total ACM was chrysotile, while crocidolite was not detected. A comparison of building material types showed that the material with the highest priority for regular management is ceiling tile, followed by roof, TSI, and surfacing material. The average airborne concentration of asbestos sampled without disturbing in-place ACM was 0.0028 fibers/cc by PCM, with all measurements below the standard of recommendation for indoor air quality in Korea (0.01 fibers/cc).

  6. Attenuation of landfill leachate by UK Triassic sandstone aquifer materials. 2. Sorption and degradation of organic pollutants in laboratory columns

    Science.gov (United States)

    Thornton, Steven F.; Bright, Mildred I.; Lerner, David N.; Tellam, John H.

    2000-05-01

    The sorption and degradation of dissolved organic matter (DOM) and 13 organic micropollutants (BTEX, aromatic hydrocarbons, chloro-aromatic and -aliphatic compounds, and pesticides) in acetogenic and methanogenic landfill leachate was studied in laboratory columns containing Triassic sandstone aquifer materials from the English Midlands. Solute sorption and degradation relationships were evaluated using a simple transport model. Relative to predictions, micropollutant sorption was decreased up to eightfold in acetogenic leachate, but increased up to sixfold in methanogenic leachate. This behaviour reflects a combination of interactions between the micropollutants, leachate DOM and aquifer mineral fraction. Sorption of DOM was not significant. Degradation of organic fractions occurred under Mn-reducing and SO 4-reducing conditions. Degradation of some micropollutants occurred exclusively under Mn-reducing conditions. DOM and benzene were not significantly degraded under the conditions and time span (up to 280 days) of the experiments. Most micropollutants were degraded immediately or after a lag phase (32-115 days). Micropollutant degradation rates varied considerably (half-lives of 8 to >2000 days) for the same compounds (e.g., TeCE) in different experiments, and for compounds (e.g., naphthalene, DCB and TeCA) within the same experiment. Degradation of many micropollutants was both simultaneous and sequential, and inhibited by the utilisation of different substrates. This mechanism, in combination with lag phases, controls micropollutant degradation potential in these systems more than the degradation rate. These aquifer materials have a potentially large capacity for in situ bioremediation of organic pollutants in landfill leachate and significant degradation may occur in the Mn-reducing zones of leachate plumes. However, degradation of organic pollutants in acetogenic leachate may be limited in aquifers with low pH buffering capacity and reducible Mn oxides

  7. Expanded polystyrene as the bearing building material of low energy construction

    Science.gov (United States)

    Mesaros, P.; Spisakova, M.; Kyjakova, L.; Mandicak, T.

    2015-01-01

    Sustainability of buildings is a really important issue for the construction industry. Sustainable buildings are characterized by the lower construction costs for energy consumption and operations, they are environmentally friendly, able to save natural resources and they are comfortable and healthy for their users. The European Union supports this trend through its Strategy 2020, respectively with document Energy Roadmap 2020. The strategy 2020 sets greenhouse gas emissions 20% lower than 1990, 20% of energy from renewable and 20% increase in energy efficiency. It manifests itself in introduction of modern technologies of house building. One potential for the energy saving is construction of low-energy buildings using modern materials. This paper focuses on the analysis of the low-energy buildings made by expanded polystyrene as the bearing building material. The paper analyzes their design and describes the benefits of this modern but unusual type of construction technology for houses. The examples from abroad clearly indicate that this technology has potential in modern architecture. The success and exploration of this technology potential in the conditions of Slovak construction sector is closely related to interest of investors and users of further sustainable houses which are design according the Strategy 2020 conditions.

  8. Characterization of organophosphorus flame retardants' sorption on building materials and consumer products

    Science.gov (United States)

    Liu, Xiaoyu; Allen, Matthew R.; Roache, Nancy F.

    2016-09-01

    Better understanding the transport mechanisms of organophosphorus flame-retardants (OPFRs) in the residential environment is important to more accurately estimate their indoor exposure and develop risk management strategies that protect human health. This study describes an improved dual small chamber testing method to characterize the sorption of OPFRs on indoor building materials and consumer products. The OPFRs studied were tris(2-chloroethyl) phosphate (TCEP), tris(1-chloro-2-propyl) phosphate (TCIPP), and tris(1,3-dichloro-2-propyl) phosphate (TDCIPP). The test materials and products used as sinks include concrete, ceiling tile, vinyl flooring, carpet, latex painted gypsum wallboard, open cell polyurethane foam, mattress pad and liner, polyester clothing, cotton clothing, and uniform shirt. During the tests, the amount of OPFRs absorbed by the materials at different exposure times was determined simultaneously. OPFRs air concentrations at the inlet and inside the test chamber were monitored. The data were used to rank the sorption strength of the OPFRs on different materials. In general, building materials exhibited relatively stronger sorption strength than clothing textiles. The material-air partition and material phase diffusion coefficients were estimated by fitting a sink model to the sorption concentration data for twelve materials with three OPFRs. They are in the range of 2.72 × 105 to 3.99 × 108 (dimensionless) for the material-air partition coefficients and 1.13 × 10-14 to 5.83 × 10-9 (m2/h) for the material phase diffusion coefficients.

  9. Hydrolysis kinetics in anaerobic degradation of particulate organic material: an overview.

    Science.gov (United States)

    Vavilin, V A; Fernandez, B; Palatsi, J; Flotats, X

    2008-01-01

    The applicability of different kinetics to the hydrolysis of particulate organic material in anaerobic digestion is discussed. Hydrolysis has traditionally been modelled according to the first-order kinetics. For complex substrate, the first-order kinetics should be modified in order to take into account hardly degradable material. It has been shown that models in which hydrolysis is coupled to the growth of hydrolytic bacteria work well at high or at fluctuant organic loading. In particular, the surface-related two-phase and the Contois models showed good fits to experimental data from a wide range of organic waste. Both models tend to the first-order kinetics at a high biomass-to-waste ratio and, for this reason, they can be considered as more general models. Examples on different inhibition processes that might affect the degradation of solid waste are reported. Acetogenesis or methanogenesis might be the rate-limiting stages in complex waste. In such cases, stimulation of hydrolysis (mechanically, chemically or biologically) may lead to a further inhibition of these stages, which ultimately affects hydrolysis as well. Since the hydrolysis process is characterized by surface and transport phenomena, new developments in spatially distributed models are considered fundamental to provide new insights in this complex process.

  10. Materials and building techniques in Mugello from the Late Middle Ages to the Early Modern Age

    Directory of Open Access Journals (Sweden)

    Andrea Arrighetti

    2017-01-01

    Full Text Available Mugello is a medium-high seismic risk area situated on the Italian Apennine mountain range, between Tuscany and Emilia Romagna. The territory is characterized by a large presence of long duration settlements characterized by well-preserved historic buildings, most of which are religious’ architectonical complexes. An area of Mugello, between 2010 and 2014, was characterized by the project “Archaeology of Buildings and seismic risk in Mugello”, a research focused on testing the potential information of the process of archaeological analysis of buildings as a form of knowledge, prevention and protection of medieval seismic risk settlements. Among the results that have emerged from the archaeoseismological investigation have played a central role the considerations pertaining to the supplying and use of building materials for the construction and modification of architectural structures, in a period between the late Middle Ages and the Modern Age.

  11. Using Selected Transient Methods for Measurements of Thermophysical Parameters of Building Materials

    Directory of Open Access Journals (Sweden)

    Cviklovič Vladimír

    2014-03-01

    Full Text Available This article deals with thermophysical properties of red and white bricks. If we want to protect the high standard of quality building materials, we need to know the physical parameters which can evaluate the quality. The most important for building materials are mainly thermophysical, mechanical parameters and parameters which can determine the structure of materials. The article presents results of thermophysical parameters measurements of red and white bricks during the temperature stabilization for different values of moisture content. For our measurements, we have chosen a hot wire method and a dynamic plane source method. Both methods are classified as transient methods and they are very convenient for measurements of thermophysical parameters of materials with a compact structure. The results of measurements show that temperature and moisture content have a significant effect on thermophysical parameters of bricks.

  12. Multicriteria Decision Analysis of Material Selection of High Energy Performance Residential Building

    Science.gov (United States)

    Čuláková, Monika; Vilčeková, Silvia; Katunská, Jana; Krídlová Burdová, Eva

    2013-11-01

    In world with limited amount of energy sources and with serious environmental pollution, interest in comparing the environmental embodied impacts of buildings using different structure systems and alternative building materials will be increased. This paper shows the significance of life cycle energy and carbon perspective and the material selection in reducing energy consumption and emissions production in the built environment. The study evaluates embodied environmental impacts of nearly zero energy residential structures. The environmental assessment uses framework of LCA within boundary: cradle to gate. Designed alternative scenarios of material compositions are also assessed in terms of energy effectiveness through selected thermal-physical parameters. This study uses multi-criteria decision analysis for making clearer selection between alternative scenarios. The results of MCDA show that alternative E from materials on nature plant base (wood, straw bales, massive wood panel) present possible way to sustainable perspective of nearly zero energy houses in Slovak republic

  13. Instruments to reduce the leaching of heavy metals from building materials in the Netherlands.

    Science.gov (United States)

    van Breemen, A J H; Vermij, P H M

    2007-01-01

    In the Netherlands the leaching of heavy metals from metal building and constructing materials results in serious contamination problems in the water system. The most common sources of these heavy metals in construction materials are copper waterworks and roofs, zinc roofs, gutters and rain pipes, zinced steel, stainless steel, and lead sealing material. In urban waters the surface water and sediment standards are often exceeded. Although building and construction materials are certainly not the only source of heavy metals, they are an important part of the problem. This article focuses on six instruments that are in use in the Netherlands to try to reduce impact on the surface waters. In addition to this, national as well as international, a reconsideration of the risks and surface water standards for several heavy metals is considered. A balanced use of instruments can be considered as the application of a best practice.

  14. Surface dispersive energy determined with IGC-ID in anti-graffiti-coated building materials

    OpenAIRE

    Carmona-Quiroga, Paula María; Rubio, J; Sánchez, M. J.; Martínez-Ramírez, Sagrario.; Blanco-Varela, María Teresa

    2011-01-01

    Coating building materials with anti-graffiti treatments hinders or prevents spray paint adherence by generating low energy surfaces. This paper describes the effect of coating cement paste, lime mortar, granite, limestone and brick with two anti-graffiti agents (a water-base fluoroalkylsiloxane, “Protectosil Antigraffiti®”, and a Zr ormosil) on the dispersive component of the surface energy of these five construction materials. The agents were rediluted in their respective solvents at concen...

  15. Critical Review of the Material Criteria of Building Sustainability Assessment Tools

    Directory of Open Access Journals (Sweden)

    Jiyoung Park

    2017-01-01

    Full Text Available Comparative analysis of the material criteria embedded in building sustainability assessment tools was performed. The material-related issues were identified, classified, and summarized. A framework, the triple bottom line of sustainability (environment, economy, and society, was used to examine the material assessment criteria, evaluation parameters, and descriptions. The material criteria were evaluated to identify the current features and weaknesses as balanced material assessments for sustainable development. The criteria showed significant differences in their scopes in covering the social and economic aspects beyond the environmental aspect. For comprehensive sustainability assessment purposes, it is essential that adequate attention be paid to all three dimensions. Finally, this paper proposes the indicators of the sustainable material assessment from an analysis of all the material-related items.

  16. Bamboo as a Building Material. Peace Corps. Appropriate Technologies for Development. Reprint R-33.

    Science.gov (United States)

    McClure, F. A.

    This manual, developed by the U.S. Department of Agriculture under the Point Four program, presents critical features and principles of using bamboo as a building material. Information provided in the manual includes the following: parts of a house for which bamboos are suitable, bamboo reinforcement of concrete, geographical distribution of…

  17. Quality improvement of granular secondary raw building materials by separation and cleansing techniques

    NARCIS (Netherlands)

    Xing, W.

    2004-01-01

    Contaminated granular wastes are potentially reusable because they have similar physical and chemical properties as primary raw building materials. From environmental aspects, the reuse must not result in polluting the soil, groundwater and surface water. Therefore the leaching values of inorganic c

  18. Environmental and Sustainable Technology Evaluations (ESTE): Verification of Microbial Resistant Building Materials

    Science.gov (United States)

    This is an ESTE project summary brief. Many of the finished interior surfaces of homes and buildings are composed of materials that are prone to mold growth. These surfaces include gypsum board, wood flooring, insulation, and components of the heating and air conditioning system...

  19. Wood would - Mass timber as a sustainable substitute for traditional building materials

    NARCIS (Netherlands)

    Struiksma, A.F.; Smilde, J.A.; Van Houten, R.S.

    2014-01-01

    This "designers' manual" is made during the TIDO-course AR0531 Innovation and Sustainability This manual explains why mass timber is the sustainable substitute for conventional materials and how it can be implemented in the design. It is intended for architects who usually always build in steel and

  20. HYDROPHOBIC PROTECTION OF BUILDING MATERIALS AND PRODUCTS WHILE USING ELECTROCHEMICAL METHODS

    OpenAIRE

    E. N. Kruchkov; N. N. Debelova; N. P. Gorlenko; I. I. Podshivalov; E. N. Zavyalova

    2010-01-01

    The paper proposes a hydrophobic protection technology of capillary-porous building materials and products obtained on their basis while using electrochemical methods. The technology includes stages of preliminary moisture removal and water-repellency treatment of product volume while applying modified solution of potassium methyl-siliconate.

  1. Radon-222 exhalation from Danish building materials: H + H Industri A/S results

    DEFF Research Database (Denmark)

    Andersen, Claus Erik

    1999-01-01

    rate measurements for 10 samples of Danish building materials are reported. Samples include ordinary concrete, lightweight aggregate concrete,autoclaved aerated concrete, bricks, and gypsum board. The maximum mass-specific exhalation rate is about 20 m Bq h"-"1 kg "-"1. Under consideration...

  2. Laboratory study of the PCB transport from primary sources to building materials

    Science.gov (United States)

    The sorption of airborne polychlorinated biphenyls (PCBs) by twenty building materials and their subsequent re-emission (desorption) from concrete were investigated using two 53-L environmental chambers connected in series with a field-collected caulk in the source chamber servin...

  3. 29 CFR 779.336 - Sales of building materials for commercial property construction.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Sales of building materials for commercial property... construction, maintenance or repair of commercial property or any other property not excepted in section 3(n... business for the construction, maintenance or repair of commercial property or any other property...

  4. Asbestos-Containing Materials in School Buildings: A Guidance Document. Part 2.

    Science.gov (United States)

    Sawyer, Robert N.; Spooner, Charles M.

    Part 2 of the Environmental Protection Agency (EPA) guidance manuals consists of more detailed information on asbestos identification and control methods. Available information on sprayed asbestos-containing materials in buildings is summarized. Guidelines are presented for the detection and monitoring, removal or encapsulation, and disposal of…

  5. Asbestos-Containing Materials in School Buildings: A Guidance Document. Part 1.

    Science.gov (United States)

    Environmental Protection Agency, Washington, DC. Office of Toxic Substances.

    The Environmental Protection Agency (EPA) has worked with the states to develop a program for accurate information and guidance to deal with the problem of school buildings constructed with asbestos-containing materials. This is the first of two guidance manuals that are a major part of this program and are being mailed to all public school…

  6. Microbes on building materials - Evaluation of DNA extraction protocols as common basis for molecular analysis

    Energy Technology Data Exchange (ETDEWEB)

    Ettenauer, Joerg D., E-mail: joerg.ettenauer@boku.ac.at [VIBT-BOKU, University of Natural Resources and Life Sciences, Department of Biotechnology, Muthgasse 11, A-1190 Vienna (Austria); Pinar, Guadalupe, E-mail: Guadalupe.Pinar@boku.ac.at [VIBT-BOKU, University of Natural Resources and Life Sciences, Department of Biotechnology, Muthgasse 11, A-1190 Vienna (Austria); Lopandic, Ksenija, E-mail: Ksenija.Lopandic@boku.ac.at [VIBT-BOKU, University of Natural Resources and Life Sciences, Department of Biotechnology, Muthgasse 11, A-1190 Vienna (Austria); Spangl, Bernhard, E-mail: Bernhard.Spangl@boku.ac.at [University of Natural Resources and Life Sciences, Department of Landscape, Spatial and Infrastructure Science, Institute of Applied Statistics and Computing (IASC), Gregor Mendel-Str. 33, A-1180 Vienna (Austria); Ellersdorfer, Guenther, E-mail: Guenther.Ellersdorfer@boku.ac.at [VIBT-BOKU, University of Natural Resources and Life Sciences, Department of Biotechnology, Muthgasse 11, A-1190 Vienna (Austria); Voitl, Christian, E-mail: Christian.Voitl@boku.ac.at [VIBT-BOKU, University of Natural Resources and Life Sciences, Department of Biotechnology, Muthgasse 11, A-1190 Vienna (Austria); Sterflinger, Katja, E-mail: Katja.Sterflinger@boku.ac.at [VIBT-BOKU, University of Natural Resources and Life Sciences, Department of Biotechnology, Muthgasse 11, A-1190 Vienna (Austria)

    2012-11-15

    The study of microbial life in building materials is an emerging topic concerning biodeterioration of materials as well as health risks in houses and at working places. Biodegradation and potential health implications associated with microbial growth in our residues claim for more precise methods for quantification and identification. To date, cultivation experiments are commonly used to gain insight into the microbial diversity. Nowadays, molecular techniques for the identification of microorganisms provide efficient methods that can be applied in this field. The efficiency of DNA extraction is decisive in order to perform a reliable and reproducible quantification of the microorganisms by qPCR or to characterize the structure of the microbial community. In this study we tested thirteen DNA extraction methods and evaluated their efficiency for identifying (1) the quantity of DNA, (2) the quality and purity of DNA and (3) the ability of the DNA to be amplified in a PCR reaction using three universal primer sets for the ITS region of fungi as well as one primer pair targeting the 16S rRNA of bacteria with three typical building materials - common plaster, red brick and gypsum cardboard. DNA concentration measurements showed strong variations among the tested methods and materials. Measurement of the DNA yield showed up to three orders of magnitude variation from the same samples, whereas A260/A280 ratios often prognosticated biases in the PCR amplifications. Visualization of the crude DNA extracts and the comparison of DGGE fingerprints showed additional drawbacks of some methods. The FastDNA Spin kit for soil showed to be the best DNA extraction method and could provide positive results for all tests with the three building materials. Therefore, we suggest this method as a gold standard for quantification of indoor fungi and bacteria in building materials. -- Highlights: Black-Right-Pointing-Pointer Up to thirteen extraction methods were evaluated with three

  7. Osteogenesis and Degradation Behavior of rhBMP-2/β-Tricalcium Phosphate Porous Composite Materials

    Institute of Scientific and Technical Information of China (English)

    Weizhong YANG; Dali ZHOU; Ge LIANG; Guangfu YIN; Yun ZHANG

    2004-01-01

    Ultrafine -tricalcium phosphate (β-TCP) powders with good crystalline structure were produced by a new wet process. Throughbone tissue engineering approach, porous β-TCP ceramic was combined with recombined human bone morphogenetic proteins- 2 (rhBMP-2) to develop a novel composite material. Osteogenesis capacity of the composite was investigated intramuscularlyin rat with histological analyses and SEM examination. Pure β-TCP porous ceramic was investigated as the control. Resultsshow that the composite materials possess good biocompatibility, biodegradation and strong osteogenesis capacity throughinductive process after implantation. Material degradation began from 2 weeks post-implantation accompanying with thechanging of pore structure, with the enwrapping and separation of materials by hyperplatic mesenchymal cells and fibroblast,and with the phagocytose reaction of multinucleated giant cells. Early in 72 h, immature cartilage could be found within novelcomposite; mature lamellar bone was induced to generate after 3 weeks. With strong osteoinduction capacity and controllablebiodegradation, the novel rhBMP-2/β-TCP porous ceramic is expected to be a promising bone grafting substitute for bonetissue engineering.

  8. Aspects regarding the use of the industrial wastes as raw materials for the manufacture of building materials

    Directory of Open Access Journals (Sweden)

    R. G. Popa

    2015-01-01

    Full Text Available In this article are present the results of physical and chemical characterisation activities, of industrial wastes: ash and slag, drilling sludge, metallurgical slag. Also, were established the conditions in which these industrial waste types could be used as raw materials for manufacture some building materials. The ash can be assimilated with a lightweight aggregate similar to the natural sands, the oil-well drilling sludge presents an advanced similarity with the suspensions of fine particles of sand clays, the steel melting slag in electric furnace has the characteristics of a dense granular aggregate and the secondary treatment steel slag is characterized by the high content of calcium oxide.

  9. Advanced phase change materials and systems for solar passive heating and cooling of residential buildings

    Energy Technology Data Exchange (ETDEWEB)

    Salyer, I.O.; Sircar, A.K.; Dantiki, S.

    1988-01-01

    During the last three years under the sponsorship of the DOE Solar Passive Division, the University of Dayton Research Institute (UDRI) has investigated four phase change material (PCM) systems for utility in thermal energy storage for solar passive heating and cooling applications. From this research on the basis of cost, performance, containment, and environmental acceptability, we have selected as our current and most promising series of candidate phase change materials, C-15 to C-24 linear crystalline alkyl hydrocarbons. The major part of the research during this contract period was directed toward the following three objectives. Find, test, and develop low-cost effective phase change materials (PCM) that melt and freeze sharply in the comfort temperature range of 73--77{degree}F for use in solar passive heating and cooling of buildings. Define practical materials and processes for fire retarding plasterboard/PCM building products. Develop cost-effective methods for incorporating PCM into building construction materials (concrete, plasterboard, etc.) which will lead to the commercial manufacture and sale of PCM-containing products resulting in significant energy conservation.

  10. Technological characteristics of compressed earth blocks for its use as a building material

    Science.gov (United States)

    Gomez-Villalba, Luz Stella; Camacho-Perez, Nancy; Alvarez de Buergo, Monica; Becerra-Becerra, Javier; Esmeralda Corredor-Pulido, Dery; Fort, Rafael

    2013-04-01

    We present here an innovative building technique, which uses ecological, inexpensive and environmentally friendly materials. These compressed earth blocks seem to be very good for building purposes and that is why we have characterized three types of compressed earth blocks (CEB, named by their color as yellow, grey and red) mineralogically by means of X ray diffraction XRD and scanning electron microscopy SEM (both blocks and raw materials), petrographically by polarizing optical light microscopy POLM, and SEM, and, mainly, petrophysically: their hydric, physical and physico-mechanical properties by means of determining their capillary water absorption, porosity (open or accessible to water, pore size distribution and micro/macroporosity), and densities, color and ultrasound velocity (together with anisotropy). The particularities of these analyzed materials show that some varieties are more durable than others, and that all of them can be used as building materials with some restrictions related to their appropriate placing in the structures and the exposure to water. Acknowledgements: This work is supported by the GEOMATERIALES (S2009/MAT-1629) and CONSOLIDER-TCP (CSD2007-0058) programmes. Thanks also to the UCM (Complutense University of Madrid) Research Group "Alteración y conservación de los materiales pétreos del patrimonio" / Alteration and conservation of heritage stone materials (ref. 921349).

  11. Comparative Thermal Analysis of Different Cool Roof Materials for Minimizing Building Energy Consumption

    Directory of Open Access Journals (Sweden)

    Y. Anand

    2014-01-01

    Full Text Available The roof and walls in the urban areas contribute to major share in the absorption of solar radiations and also retard the outflow of the absorbed radiation from the building envelope, thereby increasing the global warming by inducing the heat island effect. The impact of using cool roof technologies on the thermal comfort of the office buildings has been estimated. Cool roofs reduce electricity consumption for maintaining the temperature of the air-conditioned buildings in the comfort level and also increase comfort in buildings merely not relying completely on cooling equipment. The cool roofs and cool pavements, however, can mitigate summer urban heat islands by improving indoor air quality and comfort. The thermal analysis of different materials has been carried out to analyze the impact of the rate of heat transfer on the building envelope and the results obtained indicate that different cool roof techniques are beneficial in maintaining the comfort level of the building which purely depends on the ambient temperature conditions.

  12. Using the heat flow plate method for determining thermal conductivity of building materials

    Science.gov (United States)

    Flori, M.; Puţan, V.; Vîlceanu, L.

    2017-01-01

    The heat flow plate method is used to determine thermal conductivity of a building material sample made of Rohacell (insulating foam). Experimental technique consists in placing the sample with a reference material on top (polystyrene sample) in a calorimetric chamber and heating from underside. Considering that the heat flux which passes through the two layers is constant and knowing thermal conductivity of the reference material, the sample thermal conductivity is determined. The temperature difference between the two opposite sample’s sides is recorded only when the steady state is achieved (constant heat flux).

  13. Moisture storage parameters of porous building materials as time-dependent properties

    Science.gov (United States)

    Záleská, Martina; Pavlíková, Milena; Pavlík, Zbyšek

    2016-06-01

    Three different types of bricks and two different types of sandstones are studied in terms of measurement moisture storage parameters for over-hygroscopic moisture area using pressure plate device. For researched materials, basic physical properties as bulk density, matrix density and total open porosity are determined. From the obtained data of moisture storage measurement, the water retention curves and curves of degree of saturation in dependence on suction pressure are constructed. Water retention curve (also called suction curve, capillary potential curve, capillary-pressure function and capillary-moisture relationship) is the basic material property used in models for simulation of moisture storage in porous building materials.

  14. Effect of top electrode material on radiation-induced degradation of ferroelectric thin film structures

    Science.gov (United States)

    Brewer, Steven J.; Deng, Carmen Z.; Callaway, Connor P.; Paul, McKinley K.; Fisher, Kenzie J.; Guerrier, Jonathon E.; Rudy, Ryan Q.; Polcawich, Ronald G.; Jones, Jacob L.; Glaser, Evan R.; Cress, Cory D.; Bassiri-Gharb, Nazanin

    2016-07-01

    The effects of gamma irradiation on the dielectric and piezoelectric responses of Pb[Zr0.52Ti0.48]O3 (PZT) thin film stacks were investigated for structures with conductive oxide (IrO2) and metallic (Pt) top electrodes. The samples showed, generally, degradation of various key dielectric, ferroelectric, and electromechanical responses when exposed to 2.5 Mrad (Si) 60Co gamma radiation. However, the low-field, relative dielectric permittivity, ɛr, remained largely unaffected by irradiation in samples with both types of electrodes. Samples with Pt top electrodes showed substantial degradation of the remanent polarization and overall piezoelectric response, as well as pinching of the polarization hysteresis curves and creation of multiple peaks in the permittivity-electric field curves post irradiation. The samples with oxide electrodes, however, were largely impervious to the same radiation dose, with less than 5% change in any of the functional characteristics. The results suggest a radiation-induced change in the defect population or defect energy in PZT with metallic top electrodes, which substantially affects motion of internal interfaces such as domain walls. Additionally, the differences observed for stacks with different electrode materials implicate the ferroelectric-electrode interface as either the predominant source of radiation-induced effects (Pt electrodes) or the site of healing for radiation-induced defects (IrO2 electrodes).

  15. Re-defining the Architectural Design Process Through Building a Decision Support Framework for Design with Reused Building Materials and Components

    OpenAIRE

    Ali, Ahmed Kamal

    2012-01-01

    Waste from construction and demolition-building activities is increasing every day.Landfills have almost reached their capacity. When thinking about the negative impact ofdemolishing activities on the environment it becomes very necessary to think aboutreusing and recycling building materials in new construction or perhaps better recyclingour thoughts on how to make use of waste materials. In Kevin Lynch\\'s book, WastingAway, he wrote: "Architects must begin to think about holes in the ground...

  16. Times New Materials Company Enhancing the Technical Innovation of Building Shock Absorption and Shock Insulation Products

    Institute of Scientific and Technical Information of China (English)

    Hao Tian

    2012-01-01

    To enhance the technical innovation and market promotion of building shock absorption and shock insulation products, to promote institute-enterprise cooperation and realize complementary advantage, on March 27, Zhuzhou Times New Materials Technology Co., Ltd. concluded Framework Agreement on the Joint R&D Strategic Cooperation of Building Shock Absorption and Shock Insulation Products with Yunnan Earthquake Engineering Institute in Kunming. Both parties will fully exert their technology and resource advantages, and develop and promote shock absorption and shock insulation products jointly in the form of strategic partners.

  17. Study of Degradation Processes in Dielectric Materials Used in Electronic Control Equipment Operated in ``Kozloduy'' NPP

    Science.gov (United States)

    Naydenov, Nayden; Popov, Angel

    2007-04-01

    The electronic equipment for control of different systems of Units 5 and 6 is studied for presence of degradation processes occurring in result of continuous usage in conditions of controlled radiation background in compliance with ``Kozloduy'' NPP safety codes. Systems, operated in a continuous mode in the course of about 10 years were chosen - separate units containing different dielectric materials (varnish coating, circuit board bases, cable insulations, electro protective elements, etc.) were extrapolated. Series of test samples were prepared which were connected with flat or coaxial condensers and their characteristic parameters were measured: tgδ, ɛ, low voltage conductivity and leak currents at voltages that exceed the working ones several times. When comparing the obtained data with the reference ones, a conclusion is made about the effectiveness of electric ageing during operation in the course of time.

  18. Effects of material thickness and processing method on poly(lactic-co-glycolic acid) degradation and mechanical performance.

    Science.gov (United States)

    Shirazi, Reyhaneh Neghabat; Aldabbagh, Fawaz; Ronan, William; Erxleben, Andrea; Rochev, Yury; McHugh, Peter

    2016-10-01

    In this study, the effects of material thickness and processing method on the degradation rate and the changes in the mechanical properties of poly(lactic-co-glycolic acid) material during simulated physiological degradation were investigated. Two types of poly(lactic-co-glycolic acid) materials were considered: 0.12 mm solvent-cast films and 1 mm compression-moulded plates. The experimental results presented in this study were compared to the experimental results of Shirazi et al. (Acta Biomaterialia 10(11):4695-703, 2014) for 0.25 mm solvent-cast films. These experimental observations were used to validate the computational modelling predictions of Shirazi et al. (J Mech Behav Biomed Mater 54: 48-59, 2016) on critical diffusion length scale and also to refine the model parameters. The specific material processing methods considered here did not have a significant effect on the degradation rate and the changes in mechanical properties during degradation; however, they influenced the initial molecular weight and they determined the stiffness and hardness of the poly(lactic-co-glycolic acid) material. The experimental observations strongly supported the computational modelling predictions that showed no significant difference in the degradation rate and the changes in the elastic modulus of poly(lactic-co-glycolic acid) films for thicknesses larger than 100 μm.

  19. Fatigue degradation and failure of rotating composite structures - Materials characterisation and underlying mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Gamstedt, E.K.; Andersen, S.I.

    2001-03-01

    The present review concerns rotating composite structures, in which fatigue degradation is of key concern for in-service failure. Such applications are for instance rotor blades in wind turbines, helicopter rotor blades, flywheels for energy storage, marine and aeronautical propellers, and rolls for paper machines. The purpose is to identify areas where impending efforts should be made to make better use of composite materials in these applications. In order to obtain better design methodologies, which would allow more reliable and slender structures, improved test methods are necessary. Furthermore, the relation between structural, component and specimen test results should be better understood than what is presently the case. Improved predictive methods rely on a better understanding of the underlying damage mechanisms. With mechanism-based models, the component substructure or even the material microstructure could be optimised for best possible fatigue resistance. These issues are addressed in the present report, with special emphasis on test methods, and scaling from damage mechanisms to relevant material properties. (au)

  20. Main mechanisms of material properties degradation under reactor pressure vessel operating conditions

    Energy Technology Data Exchange (ETDEWEB)

    Karzov, Georgy; Timofeev, Boris [Central Research Inst. of Structural Materials ' prometey' , St. Petersburg (Russian Federation)

    1999-07-01

    In the process of NPP equipment operation materials are subjected to a prolonged influence of loads, associated with the variation of inner pressure and temperature under various conditions. Each equipment element damage is associated with some material fracture mechanism. For NPP equipment the mechanisms of irreversible damage accumulation are related with: irradiation embrittlement, thermal and strain aging, fatigue damages from mechanical and thermal loading, stress corrosion and fatigue corrosion, creep and thermal relaxation stresses, erosion and weak, thermal shock. The basic tasks of specialists working in the sphere of the provision of reliability and service life of nuclear power equipment are not only the determination of the main mechanisms of damages and reasons of their appearance, but also the study of methods which would permit to control these properties completely. By giving some examples of Russian NPP equipment with VVER-440 and VVER-1000 reactors the paper presents most typical degradation mechanisms of equipment material properties, including weldments, in the process of operation and methods to recover by using various technological means. (author)

  1. Early detection of critical material degradation by means of electromagnetic multi-parametric NDE

    Energy Technology Data Exchange (ETDEWEB)

    Szielasko, Klaus; Tschuncky, Ralf; Rabung, Madalina; Altpeter, Iris; Dobmann, Gerd [Fraunhofer Institute for Nondestructive Testing (IZFP), Campus E3 1, 66123 Saarbrücken (Germany); Seiler, Georg; Herrmann, Hans-Georg; Boller, Christian [Fraunhofer Institute for Nondestructive Testing (IZFP), Campus E3 1, 66123 Saarbrücken, Germany and Saarland University, Chair of NDT and Quality Assurance, Campus E3 1, 66123 Saarbrücken (Germany)

    2014-02-18

    With an increasing number of power plants operated in excess of their original design service life an early recognition of critical material degradation in components will gain importance. Many years of reactor safety research allowed for the identification and development of electromagnetic NDE methods which detect precursors of imminent damage with high sensitivity, at elevated temperatures and in a radiation environment. Regarding low-alloy heat-resistant steel grade WB 36 (1.6368, 15NiCuMoNb5), effects of thermal and thermo-mechanical aging on mechanical-technological properties and several micromagnetic parameters have been thoroughly studied. In particular knowledge regarding the process of copper precipitation and its acceleration under thermo-mechanical load has been enhanced. Whilst the Cu-rich WB 36 steel is an excellent model material to study and understand aging effects related to neutron radiation without the challenge of handling radioactive specimens in a hot cell, actually neutron-irradiated reactor pressure vessel materials were investigated as well. The neutron fluence experienced and the resulting shift of the ductile-brittle transition temperature were determined electromagnetically, and it was shown that weld and base material can be distinguished from the cladded side of the RPV wall. Low-cycle fatigue of the austenitic stainless steel AISI 347 (1.4550, X6CrNiNb18-10) has been characterized with electromagnetic acoustic transducers (EMATs) at temperatures of up to 300 °C. Time-of-flight and amplitude of the transmitted ultrasound signal were evaluated against the number of load cycles applied and observed as an indication of the imminent material failure significantly earlier than monitoring stresses or strains.

  2. Early detection of critical material degradation by means of electromagnetic multi-parametric NDE

    Science.gov (United States)

    Szielasko, Klaus; Tschuncky, Ralf; Rabung, Madalina; Seiler, Georg; Altpeter, Iris; Dobmann, Gerd; Herrmann, Hans-Georg; Boller, Christian

    2014-02-01

    With an increasing number of power plants operated in excess of their original design service life an early recognition of critical material degradation in components will gain importance. Many years of reactor safety research allowed for the identification and development of electromagnetic NDE methods which detect precursors of imminent damage with high sensitivity, at elevated temperatures and in a radiation environment. Regarding low-alloy heat-resistant steel grade WB 36 (1.6368, 15NiCuMoNb5), effects of thermal and thermo-mechanical aging on mechanical-technological properties and several micromagnetic parameters have been thoroughly studied. In particular knowledge regarding the process of copper precipitation and its acceleration under thermo-mechanical load has been enhanced. Whilst the Cu-rich WB 36 steel is an excellent model material to study and understand aging effects related to neutron radiation without the challenge of handling radioactive specimens in a hot cell, actually neutron-irradiated reactor pressure vessel materials were investigated as well. The neutron fluence experienced and the resulting shift of the ductile-brittle transition temperature were determined electromagnetically, and it was shown that weld and base material can be distinguished from the cladded side of the RPV wall. Low-cycle fatigue of the austenitic stainless steel AISI 347 (1.4550, X6CrNiNb18-10) has been characterized with electromagnetic acoustic transducers (EMATs) at temperatures of up to 300 °C. Time-of-flight and amplitude of the transmitted ultrasound signal were evaluated against the number of load cycles applied and observed as an indication of the imminent material failure significantly earlier than monitoring stresses or strains.

  3. Impact of temperature and humidity on chemical and sensory emissions from building materials.

    Science.gov (United States)

    Fang, L; Clausen, G; Fanger, P O

    1999-09-01

    The chemical and sensory emissions from five building materials (carpet, polyvinyl chloride (PVC) flooring, sealant, floor varnish and wall paint) were tested under different combinations of temperature and relative humidity in the ranges 18-28 degrees C and 30-70% relative humidity (RH). The experiment was performed in a climate chamber where a specially designed test system was built to study emissions from the five materials. The test system could provide different temperatures and humidities of air around the materials, while the air, after being polluted by the emissions from the materials, could be reconditioned to 23 degrees C and 50% RH for sensory assessments. The experiment was designed to separate the direct impact of temperature and humidity on perception from the impact on sensory emission. The study found little influence of temperature on the emissions from the five materials whether expressed in chemical or sensory terms. The effect of humidity was found to be significant only for the waterborne materials--floor varnish and wall paint. Compared with the direct impact of temperature and humidity on the perception of air quality, the impact of temperature and humidity on sensory emissions from the building materials has a secondary influence on perceived air quality.

  4. Assessment of suitability of some chosen functions for describing of sorption isotherms in building materials

    Science.gov (United States)

    Stolarska, Agata; Garbalińska, Halina

    2016-10-01

    This paper presents results of tests and studies conducted on six common building materials, used for constructing and finishing of external walls. These included: ceramic brick, silicate brick, autoclaved aerated concrete, cement mortar, cement-lime mortar and cement mortar modified with polypropylene fibers. Each of these materials is distinguished by the other structure of porousness, affecting both the course of sorption processes and the isotherms obtained. At first, measurements of moisture sorption kinetics at temperatures of 5, 20 and 35 °C were performed, each time at six levels of relative humidity. Then, when the sorption processes expired, equilibrium moisture sorption values were determined for the materials in 18 individual temperature and humidity conditions. The experimental data were used to determine the sorption isotherm courses for each material at the three temperatures. Then, theoretical analysis was performed in order to determine, which of the models available in the literature described the sorption isotherms of the concerned building materials the best. For each material and each of the three temperature values, twenty-four equations were tested. In each case, those of them were identified which ensured the best matching between the theoretical courses and the experimental data. The obtained results indicate that the Chen's model proved to be the most versatile. It ensured a detailed description of the sorption isotherms for each material and temperature tested.

  5. Solving real decay and conservation problems of building materials by ultrasounds technique

    Science.gov (United States)

    Alvarez de Buergo, Monica; Fort, Rafael; Gomez-Heras, Miguel; Vazquez-Calvo, Carmen

    2010-05-01

    In this study a variety of case studies and different building materials in which ultrasounds velocity played a significant role are shown, either to characterize building materials, to measure deterioration, to assess conservation techniques or for preventive purposes. Regarding to materials properties, ultrasounds velocity provided interesting indices such as the quality index (useful when selecting replacing materials, materials for new constructions or either for sculptures); alteration index (very much related to pores and voids, and fissures); mechanical strength (assessing its reduction when materials are affected by several decay processes, being fire one of them) or anisotropy indices, which highly condition the decay of elements and materials in buildings and sculptures, and which vary themselves with decay progress. The technique is also a tool for detecting and locating elements inside structures, like metallic ones, and also to detect and locate discontinuities inside elements, both for consolidation purposes or even in cases of structures movement, which is quite common nowadays. Using some specific software, ultrasounds results can be plotted as iso-areas, which allows to define areas or zones of structures with the highest risk of detachment in a short-time in order to plan the most adequate interventions. Not new is also the aid of ultrasonics to assess consolidation products and to determine the degree of materials decay when submitted to artificial ageing. Much more innovative is the fact that ultrasonics measurement can be also helpful to determine different building periods in a same building, even the fact of determining an element's lifetime. The results obtained by this non destructive and portable technique that will be presented in this session correspond to both real case studies (results that helped to solve a real problem), some of them corresponding to emblematic monuments de España (Royal Palace of Madrid and some other monuments

  6. Corrosion/Degradation Monitoring Technology for Composite Materials used to Extend Building Service Life

    Science.gov (United States)

    2014-07-01

    Michael K. McInerney, Orange S. Marshall, L.D. Stephenson, Ashok Kumar, Lawrence Clark, Chris Olaes , and Vishal Shinde July 2014 Approved for... Olaes Mandaree Enterprise Corporation. 812 Park Drive Warner Robins, GA 31088 Vishal Shinde Physical Acoustic Corporation 195 Clarksville Road...the probe. C-scan presentations are produced with an automat- ed data acquisition system. Typically, a data collection gate is established on the A

  7. ENVIRONMENTAL ETHICS IN GOVERNING RECYCLED MATERIAL STYROFOAM FOR BUILDING HUMAN HABITAT

    Directory of Open Access Journals (Sweden)

    Kartini Aboo Talib Khalid

    2012-01-01

    Full Text Available Styrofoam is extensively used in food packaging businesses throughout the world. Its light weight makes it a favorite food package for entrepreneurs in food businesses. However, unlike its content, the food, which decomposed easily after some time, Styrofoam remains un-decomposed due to its oil-based structure. This study discusses the prospects of re-utilization of Styrofoam as environmentally friendly recycled material. This study uses the data from an exploratory survey on the usage of Styrofoam for food packaging-conducted in the district of Bangi, Malaysia-to highlight the magnitude of Styrofoam-waste generated in these activities. The study shows that Styrofoam can be used in combination of cement and concrete to produce a light weight, energy efficient and strong building can be built. Since there are a lot of supplies of waste Styrofoam, this material can be re-used in as part of construction material. In addition the use of Styrofoam in construction could be an innovative way for constructing termite’s free buildings. This study shows that recycling Styrofoam can assist in building environmentally friendly and cost efficient human habitat. Styrofoam can be channeled for a good cause and ways of governing the recycled materials. As such, the industrial waste generated by Styrofoam can be turned into other uses, thus reducing its environmental problems.

  8. Metabolic activity of moulds as a factor of building materials biodegradation.

    Science.gov (United States)

    Gutarowska, Beata

    2010-01-01

    This paper presents the effect of building materials on the growth and metabolic activity of moulds. In cultures of Aspergillus and Penicillium moulds grown on a model medium with the addition of building materials, the biomass of mycelium, its cellular components--glucan, chitin, ergosterol and the spectrum of enzymes and organic acids produced in the medium were investigated. It was found that on the medium with wallpaper moulds produced more biomass and extracellular enzymes, mainly glycolytic ones. On medium with mortar the growth of mycelium was impeded, production of biomass was 60% smaller, the quantity of chitin, glucan and ergosterol decreased 13-41%, and the activity of most enzymes was reduced; however the moulds intensively produced organic acids: malic, succinic and oxalic acid. The largest acid production activity was found in medium with addition of mortar; moulds produced the greatest variety of acids and in greater quantities than in the control medium. Metabolic activity of the moulds depends on the type of building material, and may lead to biodeterioration of these materials.

  9. Radon-222 exhalation from Danish building materials: H + H Industri A/S results

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, C.E

    1999-08-01

    This report describes a closed-chamber method for laboratory measurements of the rate at which radon-222 degasses (exhales) from small building material samples. The chamber is 55 L in volume and the main sample geometry is a slab of dimensions 5x30x30 cm{sup 3} . Numerical modelling is used to assess (and partly remove) the bias of the method relative to an ideal measurement of the free exhalation rate. Experimental results obtained with the method are found to be in agreement with the results of an open-chamber method (which is subject to different sources of error). Results of radon-222 exhalation rate measurements for 10 samples of Danish building materials are reported. Samples include ordinary concrete, lightweight aggregate concrete, autoclaved aerated concrete, bricks, and gypsum board. The maximum mass-specific exhalation rate is about 20 mBq h{sup -1} kg{sup -1}. Under consideration of the specific applications of the investigated building materials, the contribution to the indoor radon-222 concentration in a single-family reference house is calculated. Numerical modelling is used to help extrapolate the laboratory measurements on small samples to full scale walls. Application of typical materials will increase the indoor concentration by less than 10 Bq m{sup -3}. (au) 6 tabs., 15 ills., 29 refs.

  10. Ozone deposition velocities, reaction probabilities and product yields for green building materials

    Science.gov (United States)

    Lamble, S. P.; Corsi, R. L.; Morrison, G. C.

    2011-12-01

    Indoor surfaces can passively remove ozone that enters buildings, reducing occupant exposure without an energy penalty. However, reactions between ozone and building surfaces can generate and release aerosols and irritating and carcinogenic gases. To identify desirable indoor surfaces the deposition velocity, reaction probability and carbonyl product yields of building materials considered green (listed, recycled, sustainable, etc.) were quantified. Nineteen separate floor, wall or ceiling materials were tested in a 10 L, flow-through laboratory reaction chamber. Inlet ozone concentrations were maintained between 150 and 200 ppb (generally much lower in chamber air), relative humidity at 50%, temperature at 25 °C and exposure occurred over 24 h. Deposition velocities ranged from 0.25 m h -1 for a linoleum style flooring up to 8.2 m h -1 for a clay based paint; reaction probabilities ranged from 8.8 × 10 -7 to 6.9 × 10 -5 respectively. For all materials, product yields of C 1 thru C 12 saturated n-aldehydes, plus acetone ranged from undetectable to greater than 0.70 The most promising material was a clay wall plaster which exhibited a high deposition velocity (5.0 m h -1) and a low product yield (

  11. Raman scattering or fluorescence emission? Raman spectroscopy study on lime-based building and conservation materials.

    Science.gov (United States)

    Kaszowska, Zofia; Malek, Kamilla; Staniszewska-Slezak, Emilia; Niedzielska, Karina

    2016-12-05

    This work presents an in-depth study on Raman spectra excited with 1064 and 532nm lasers of lime binders employed in the past as building materials and revealed today as valuable conservation materials. We focus our interest on the bands of strong intensity, which are present in the spectra of all binders acquired with laser excitation at 1064nm, but absent in the corresponding spectra acquired with laser excitation at 532nm. We suggest, that the first group of spectra represents fluorescence phenomena of unknown origin and the second true Raman scattering. In our studies, we also include two other phases of lime cycle, i.e. calcium carbonate (a few samples of calcite of various origins) and calcium oxide (quicklime) to assess how structural and chemical transformations of lime phases affect the NIR-Raman spectral profile. Furthermore, we analyse a set of carbonated limewashes and lime binders derived from old plasters to give an insight into their spectral characteristics after excitation with the 1064nm laser line. NIR-Raman micro-mapping results are also presented to reveal the spatial distribution of building materials and fluorescent species in the cross-section of plaster samples taken from a 15th century chapel. Our study shows that the Raman analysis can help identify lime-based building and conservation materials, however, a caution is advised in the interpretation of the spectra acquired using 1064nm excitation.

  12. Building services cabinets as teaching material in a degree in architecture

    Science.gov (United States)

    Martín-Gómez, César; Zapata, Omayra; Zuazua, Amaia; Villanueva, Sonia; Olaizola, Paula

    2014-03-01

    The aim of this innovative educational project is to encourage students' interest in one of the most underrated fields of architecture: building services. With this material students interact with real elements and thereby understand the relationship between facilities and the building. A set of three small technical cabinets is planned. They allow for comfortable use and movement inside the building, need minimum maintenance and are easily stored. The result is an alternative concept of a mobile laboratory called a 'technical cabinet', made up of three mobile units for fire safety, electricity and the heating/cooling system. The design, content and learning systems of the cabinets confirmed the validity of the initial concept during the first year of use. A protocol has also been developed for each of the technical cabinets so that the teaching experience may be of use in other Schools of Architecture.

  13. J.A. van der Kloes (1845-1935): A professional biography of the first Dutch professor in building materials

    NARCIS (Netherlands)

    Quist, W.J.

    2015-01-01

    Prof. Jacobus Alida van der Kloes (1845-1935) was appointed teacher in building materials at the “Polytechnische school” of Delft in 1882. From 1905 until his retirement in 1915 he was promoted to full professor on the subject of knowledge and research of building materials at the “Technische Hooges

  14. Screening for halogenated flame retardants in European consumer products, building materials and wastes.

    Science.gov (United States)

    Vojta, Šimon; Bečanová, Jitka; Melymuk, Lisa; Komprdová, Klára; Kohoutek, Jiří; Kukučka, Petr; Klánová, Jana

    2017-02-01

    To fulfill national and international fire safety standards, flame retardants (FRs) are being added to a wide range of consumer products and building materials consisting of flammable materials like plastic, wood and textiles. While the FR composition of some products and materials has been identified in recent years, the limited global coverage of the data and the large diversity in consumer products necessitates more information for an overall picture of the FR composition in common products/materials. To address this issue, 137 individual samples of various consumer products, building materials and wastes were collected. To identify and characterize potential sources of FRs in indoor environment, all samples were analyzed for content of polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDDs) and novel flame retardants (NFRs). The most frequently detected were HBCDDs (85%), with the highest median concentration of Σ4HBCDDs of 300 mg kg(-1) in polystyrenes. The highest median concentration of Σ10PBDEs was found in recycled plastic materials, reaching 4 mg kg(-1). The lowest concentrations were observed for NFRs, where the median of Σ12NFRs reached 0.4 mg kg(-1) in the group of electrical & electronic equipment wastes. This suggests that for consumer products and building materials that are currently in-use, legacy compounds still contribute to the overall burden of FRs. Additionally, contrasting patterns of FR composition in recycled and virgin plastics, revealed using principle component analysis (PCA), suggest that legacy flame retardants are reentering the market through recycled products, perpetuating the potential for emissions to indoor environments and thus for human exposure.

  15. Modeling of heat evolution in silicate building materials with electrically conductive admixtures

    Science.gov (United States)

    Fiala, Lukáš; Maděra, Jiří; Vejmelková, Eva; Černý, Robert

    2016-12-01

    Silicate building materials are electrically non-conductive, in general. However, a sufficient amount of electrically conductive admixtures can significantly increase their electrical conductivity. Consequently, new practical applications of such materials are available. Materials with enhanced electrical properties can be used as self-sensing sensors monitoring evolution of cracks, electromagnetic shields or cores of deicing systems. This paper deals with the modeling of heat evolution in silicate building materials by the action of passing electric current. Due to the conducting paths formed in the material's matrix by adding a sufficient amount of electrically conductive admixture and applying electric voltage on the installed electrodes, electric current is passing through the material. Thanks to the electric current, Joule heat is successively evolved. As it is crucial to evaluate theoretically the amount of evolved heat in order to assess the effectiveness of such a system, a model describing the Joule heat evolution is proposed and a modeling example based on finite-element method is introduced.

  16. Infrared Emissivity Measurements of Building and Civil Engineering Materials: A New Device for Measuring Emissivity

    Science.gov (United States)

    Monchau, Jean-Pierre; Marchetti, Mario; Ibos, Laurent; Dumoulin, Jean; Feuillet, Vincent; Candau, Yves

    2014-10-01

    The knowledge of the infrared emissivity of materials used in buildings and civil engineering structures is useful for two specific approaches. First, quantitative diagnosis of buildings or civil engineering infrastructures by infrared thermography requires emissivity values in the spectral bandwidth of the camera used for measurements, in order to obtain accurate surface temperatures; for instance, emissivity in the band III domain is required when using cameras with uncooled detectors (such as micro-bolometer arrays). Second, setting up accurate thermal balances by numerical modeling requires the total emissivity value for a large wavelength domain; this is, for instance, the case for computing the road surface temperature to predict ice occurrence. Furthermore, periodical surveys of emissivity variations due to aging or soiling of surfaces could be useful in many situations such as thermal mapping of roads or building insulation diagnosis. The use of portable emissivity measurement devices is required for that purpose. A device using an indirect measurement method was previously developed in our lab; the method uses measurement of the reflectivity from a modulated IR source and requires calibration with a highly reflective surface. However, that device uses a low-frequency, thermal modulation well adapted to laboratory measurements but unfit for fast and in situ measurements. Therefore, a new, portable system which retains the principle of an indirect measurement but uses a faster-frequency, mechanical modulation more appropriate to outdoor measurements was developed. Both devices allow measurements in the broad m to m) and narrow m to m) bands. Experiments were performed on a large number of materials commonly used in buildings and civil engineering structures. The final objective of this work is to build a database of emissivity of these materials. A comparison of laboratory and on-site measurements of emissivity values obtained in both spectral bands will be

  17. Life Cycle Assessment of the inclusion of phase change materials (PCM) in experimental buildings

    Energy Technology Data Exchange (ETDEWEB)

    de Gracia, Alvaro; Rincon, Lidia; Castell, Albert; Medrano, Marc; Cabeza, Luisa F. [GREA Innovacio concurrent, Edifici CREA, Universitat de Lleida, Pere de Cabrera s/n, 25001 Lleida (Spain); Jimenez, Melanie; Boer, Dieter [Department of Mechanical Engineering, Universitat Rovira i Virgili, Av. Paisos Catalans, 26, 43007 Tarragona (Spain)

    2010-09-15

    The present work evaluates the environmental impact of including phase change materials (PCM) in a typical Mediterranean building. A Life Cycle Assessment (LCA) is developed for three monitored cubicles built in Puigverd de Lleida (Spain). It is possible to control the inner temperature of the cubicles using a domestic heat pump for cooling and an electrical radiator for heating: The energy consumption is registered to determine the energy savings achieved. The aim is to analyze if these energy savings are large enough to balance the environmental impact originated during the manufacturing of PCM. Some hypothetical scenarios, such as different systems to control the temperature different PCM types or different weather conditions are proposed and studied using LCA process to point out the critical issues. Furthermore, a parametric analysis of the lifetime of buildings is developed. Results show that the addition of PCM in the building envelope, although decreasing the energy consumption during operation, does not reduce significantly the global impact throughout the lifetime of the building. For the hypothetical scenario considering summer conditions all year around and a lifetime of the building of 100 years, the use of PCM reduces the overall impact by more than 10%. (author)

  18. A new alkali-activated steel slag-based cementitious material for photocatalytic degradation of organic pollutant from waste water

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yao Jun, E-mail: yaojzhang@yahoo.com.cn [College of Material Science and Engineering, Xi' an University of Architecture and Technology, Xi' an 710055 (China); Liu, Li Cai; Xu, Yong; Wang, Ya Chao; Xu, De Long [College of Material Science and Engineering, Xi' an University of Architecture and Technology, Xi' an 710055 (China)

    2012-03-30

    Highlights: Black-Right-Pointing-Pointer A novel Ni,Ca-cementitious material is synthesized by a two-step reaction. Black-Right-Pointing-Pointer Ni,Ca-geopolymer is firstly used for the photocatalytic degradation of MB. Black-Right-Pointing-Pointer Absorption bands in the UV and NIR regions are reported for the first time. Black-Right-Pointing-Pointer A reaction mechanism of photocatalytic degradation was proposed. - Abstract: A new type of Ni,Ca-cementitious material was firstly synthesized via a two-step reaction of alkali-activated steel slag polymerization and ion exchange. The XRF results showed that almost all the Na{sup +} ions in the matrix of Na,Ca-cementitious material were replaced by Ni{sup 2+} ions at room temperature. The new hydrated products of metahalloysite (Si{sub 2}Al{sub 2}O{sub 5}(OH){sub 4}) and calcium silicate hydrate (CSH) were formed in the Na,Ca-cementitious material. The diffuse reflectance UV-vis near infrared ray spectrum was blue-shifted due to the strong interaction between Ni{sup 2+} and negative charge of [AlO{sub 4}]{sup 5-} tetrahedron in the framework of cementitious material. The Ni,Ca-cementitious material was used as a catalyst for the photocatalytic degradation of methylene blue dye and showed a degradation rate of 94.39% under UV irradiation. The high photocatalytic degradation activity was suggested to be the synergistic effect of the cementitious matrix, Ni{sup 2+} ions and the iron oxides of wustite (FeO) and calcium iron oxide (Ca{sub 2}Fe{sub 2}O{sub 5}) from the steel slag. A probable mechanism of photocatalytic oxidative degradation was proposed.

  19. Comparison of three different DNA extraction methods from a highly degraded biological material.

    Science.gov (United States)

    Kuś, M; Ossowski, A; Zielińska, G

    2016-05-01

    The identification of unknown victims is one of the most challenging tasks faced by forensic medicine. This is due to the rapid decomposition of tissues, beginning at the moment of death and caused by released enzymes and microbial activity. Decay is directly associated with the decomposition of soft tissues and also the degradation of genetic material inside cells. Decomposition rates vary depending on a number of environmental factors, including temperature, humidity, season, and soil properties. Decomposition also differs between bodies left in the open air or buried. To date, forensic medicine has identified mainly people who were the victims of various types of criminal offences. However, with advances in identification methods, increasingly frequent attempts are made to identify the victims of armed conflicts, crimes of totalitarian regimes, or genocide. The aim of the study was to compare three different methods for the extraction of nuclear DNA from material considered in forensic medicine as difficult to handle, i.e. fragments of bones and teeth, and to determine the performance of these methods and their suitability for identification procedures.

  20. Thermal and chemical degradation of inorganic membrane materials. Final report, August 1992--May 1995

    Energy Technology Data Exchange (ETDEWEB)

    Damle, A.S.; Krishnan, G.N.; Sanjurjo, A.; Wood, B.J.; Lau, K.H.

    1995-05-01

    SRI International conducted a theoretical and experimental program to evaluate the long-term thermal and chemical degradation of inorganic membranes that are being developed to separate the gaseous products of coal gasification. A variety of developmental efforts are underway, including a number of projects sponsored by the US Department of Energy (DOE), to improve the selectivity and permeability of porous inorganic membranes. DOE is also sponsoring efforts to extend the use of metallic membranes to new applications. Most developmental efforts have focused on hydrogen separation by inorganic membranes, which may be used to maximize hydrogen production from coal gas or to remove H{sub 2}S and NH{sub 3} contaminants via thermal or catalytic decomposition in integrated-gasification combined-cycle (IGCC) systems. Inorganic membranes that have a high separation efficiency and exhibit both thermal and chemical stability would improve the economics of power generation from coal. Membrane materials that have been investigated include glass (silica), alumina, carbon, and metals (Pd and Pt). This report describes inorganic membrane materials, long term membrane exposure tests, membrane permeation tests, coal gasifier exposure tests, conclusions, and recommendations.

  1. In vitro degradation and cell response of calcium carbonate composite ceramic in comparison with other synthetic bone substitute materials

    Energy Technology Data Exchange (ETDEWEB)

    He, Fupo [Department of Biomedical Engineering, School of Basic Sciences, Guangzhou Medical University, Guangzhou 510182 (China); Zhang, Jing [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 (China); Yang, Fanwen; Zhu, Jixiang; Tian, Xiumei [Department of Biomedical Engineering, School of Basic Sciences, Guangzhou Medical University, Guangzhou 510182 (China); Chen, Xiaoming, E-mail: xmchenw@126.com [Department of Biomedical Engineering, School of Basic Sciences, Guangzhou Medical University, Guangzhou 510182 (China)

    2015-05-01

    The robust calcium carbonate composite ceramics (CC/PG) can be acquired by fast sintering calcium carbonate at a low temperature (650 °C) using a biocompatible, degradable phosphate-based glass (PG) as sintering agent. In the present study, the in vitro degradation and cell response of CC/PG were assessed and compared with 4 synthetic bone substitute materials, calcium carbonate ceramic (CC), PG, hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) ceramics. The degradation rates in decreasing order were as follows: PG, CC, CC/PG, β-TCP, and HA. The proliferation of rat bone mesenchymal stem cells (rMSCs) cultured on the CC/PG was comparable with that on CC and PG, but inferior to HA and β-TCP. The alkaline phosphatase (ALP) activity of rMSCs on CC/PG was lower than PG, comparable with β-TCP, but higher than HA. The rMSCs on CC/PG and PG had enhanced gene expression in specific osteogenic markers, respectively. Compared to HA and β-TCP, the rMSCs on the CC/PG expressed relatively lower level of collagen I and runt-related transcription factor 2, but showed more considerable expression of osteopontin. Although CC, PG, HA, and β-TCP possessed impressive performances in some specific aspects, they faced extant intrinsic drawbacks in either degradation rate or mechanical strength. Based on considerable compressive strength, moderate degradation rate, good cell response, and being free of obvious shortcoming, the CC/PG is promising as another choice for bone substitute materials. - Highlights: • A calcium carbonate composite ceramic (CC/PG) was acquired. • The in vitro degradation and cell response of CC/PG were compared to 4 materials. • The CC/PG showed moderate degradation rate. • The CC/PG exhibited good cell response. • The CC/PG was free of obvious drawback compared to other materials.

  2. Identification of construction material pathologies in historical buildings using infrared thermography

    OpenAIRE

    Lerma Elvira, Carlos; Mas Tomas, Maria De Los Angeles; Gil Benso, Enrique; VERCHER SANCHIS, JOSÉ MARÍA

    2013-01-01

    [en] Study of historic buildings requires a pathology analysis of the construction materials used in order to define their conservation state. Usually we can find capillary moisture, salt crystallization or density differences by deterioration. Sometimes this issue is carried out by destructive testing which determine materials’ physical and chemical characteristics. However, they are unfavorable regarding the building’s integrity, and they are sometimes difficult to implement. This paper pre...

  3. Building Materials Realized with Ultra-Fine Fly Ash and Silica Fume

    Directory of Open Access Journals (Sweden)

    Cătălin Badea

    2005-01-01

    Full Text Available The author’s experimental researches presented in this paper were focused on the building materials obtained by using ultra-fine fly ash and silica fume (like heavy mortars or compacted lightweight concretes. From experimental determinations there have been studied the following characteristics: the water absorption in function of mass, apparent density, tensile and compression strength (at 7 and 28 days, technical efficiency at 28 days and shrinkage.

  4. The true value of materials:BRIDGE (Building Research and Innovation Deals for the Green Economy)

    OpenAIRE

    Farrer, Joan; Watt, Carolyn A.

    2015-01-01

    Assessing the value of materials, lifecycle and applications was central to the European Union INTERREG IV project BRIDGE (Building Research and Innovation Deals for the Green Economy) 2011–2014. Here, the complex philosophies of sustainability (protection of people, profit and planet) underpinned innovation, knowledge transfer, data visualization and design thinking, to develop green entrepreneurs, and market differentiation in Southern England and Northern France Channel regions. The model ...

  5. Aerophytic Cyanobacteria as a Factor in the Biodegradation of Technical Materials on External Building Walls

    Directory of Open Access Journals (Sweden)

    Piontek Marlena

    2014-12-01

    Full Text Available A study conducted at the Institute of Environmental Engineering, University of Zielona Góra showed the presence of 4 species of aerophytic cyanobacteria in the biological material sampled from the external building wall with visible biocorrosion: Gloeocapsa montana Kützing, Phormidium calcareum Kützing, Aphanothece saxicola Nägeli, Gloeothece caldariorum (P. Richter Hollerbach. High levels of moisture were detected in the places of biofilm occurrence.

  6. Aerophytic Cyanobacteria as a Factor in the Biodegradation of Technical Materials on External Building Walls

    Science.gov (United States)

    Piontek, Marlena; Lechów, Hanna

    2014-12-01

    A study conducted at the Institute of Environmental Engineering, University of Zielona Góra showed the presence of 4 species of aerophytic cyanobacteria in the biological material sampled from the external building wall with visible biocorrosion: Gloeocapsa montana Kützing, Phormidium calcareum Kützing, Aphanothece saxicola Nägeli, Gloeothece caldariorum (P. Richter) Hollerbach. High levels of moisture were detected in the places of biofilm occurrence.

  7. Fundamental mass transfer modeling of emission of volatile organic compounds from building materials

    Science.gov (United States)

    Bodalal, Awad Saad

    In this study, a mass transfer theory based model is presented for characterizing the VOC emissions from building materials. A 3-D diffusion model is developed to describe the emissions of volatile organic compounds (VOCs) from individual sources. Then the formulation is extended to include the emissions from composite sources (system comprising an assemblage of individual sources). The key parameters for the model (The diffusion coefficient of the VOC in the source material D, and the equilibrium partition coefficient k e) were determined independently (model parameters are determined without the use of chamber emission data). This procedure eliminated to a large extent the need for emission testing using environmental chambers, which is costly, time consuming, and may be subject to confounding sink effects. An experimental method is developed and implemented to measure directly the internal diffusion (D) and partition coefficients ( ke). The use of the method is illustrated for three types of VOC's: (i) Aliphatic Hydrocarbons, (ii) Aromatic Hydrocarbons and ( iii) Aldehydes, through typical dry building materials (carpet, plywood, particleboard, vinyl floor tile, gypsum board, sub-floor tile and OSB). Then correlations for predicting D and ke based solely on commonly available properties such as molecular weight and vapour pressure were proposed for each product and type of VOC. These correlations can be used to estimate the D and ke when direct measurement data are not available, and thus facilitate the prediction of VOC emissions from the building materials using mass transfer theory. The VOC emissions from a sub-floor material (made of the recycled automobile tires), and a particleboard are measured and predicted. Finally, a mathematical model to predict the diffusion coefficient through complex sources (floor adhesive) as a function of time was developed. Then this model (for diffusion coefficient in complex sources) was used to predict the emission rate from

  8. CASTOR OIL-BASED BUILDING MATERIALS REINFORCED WITH FLY ASH, CLAY, EXPANDED PERLITE AND PUMICE POWDER

    Directory of Open Access Journals (Sweden)

    Figen Balo

    2011-09-01

    Full Text Available This paper reports the results of a study conducted to evaluate the influence of class C fly ash (FA, clay (C, expanded perlite (EP, pumice powder (PP and epoxidized castor oil (ECO on the density, thermal conductivity, compressive strength, tensile strength, abrasion loss and water absorption of building material. Density, thermal conductivity, compressive strength and tensile strength decreased with the increase of ECO and FA as replacement for building material. These properties also decreased with increasing process temperature. The addition of clay in the building material had an increasing effect on these properties. The addition of clay decreased abrasion loss and water absorption as a function of replacement percent. The minimum thermal conductivity and maximum water absorption observed for the sample made with minimum clay and maximum FA-ECO ratios processed at the highest process temperature. The maximum compression-tensile strengths and minimum abrasion loss observed for the sample with maximum clay and minimum FA-ECO ratios processed at the lowest process temperature.

  9. Measurement of radon exhalation rate in various building materials and soil samples

    Science.gov (United States)

    Bala, Pankaj; Kumar, Vinod; Mehra, Rohit

    2017-03-01

    Indoor radon is considered as one of the potential dangerous radioactive elements. Common building materials and soil are the major source of this radon gas in the indoor environment. In the present study, the measurement of radon exhalation rate in the soil and building material samples of Una and Hamirpur districts of Himachal Pradesh has been done with solid state alpha track detectors, LR-115 type-II plastic track detectors. The radon exhalation rate for the soil samples varies from 39.1 to 91.2 mBq kg-1 h-1 with a mean value 59.7 mBq kg-1 h-1. Also the radium concentration of the studied area is found and it varies from 30.6 to 51.9 Bq kg-1 with a mean value 41.6 Bq kg-1. The exhalation rate for the building material samples varies from 40.72 (sandstone) to 81.40 mBq kg-1 h-1 (granite) with a mean value of 59.94 mBq kg-1 h-1.

  10. Measurement of radon exhalation rate in various building materials and soil samples

    Indian Academy of Sciences (India)

    Pankaj Bala; Vinod Kumar; Rohit Mehra

    2017-03-01

    Indoor radon is considered as one of the potential dangerous radioactive elements. Common building materials and soil are the major source of this radon gas in the indoor environment. In the present study, the measurement of radon exhalation rate in the soil and building material samples of Una and Hamirpurdistricts of Himachal Pradesh has been done with solid state alpha track detectors, LR-115 type-II plastic track detectors. The radon exhalation rate for the soil samples varies from 39.1 to 91.2 mBq kg⁻¹ h⁻¹with a mean value 59.7 mBq kg⁻¹ h⁻¹. Also the radium concentration of the studied area is found and it varies from 30.6 to 51.9 Bq kg⁻¹ with a mean value 41.6 Bq kg⁻¹ . The exhalation rate for the building material samples varies from 40.72 (sandstone) to 81.40 mBq kg⁻¹ h⁻¹ (granite) with a mean value of59.94 mBq kg⁻¹ h⁻¹.

  11. Building material characterization by using IR thermography for efficient heating systems

    Science.gov (United States)

    Bison, Paolo; Grinzato, Ermanno

    2008-03-01

    Thermography is excellent for a fast characterisation of building materials, both at laboratory or in situ. A great advantage is the possibility to analyse many samples at the same conditions and time. A technique has been applied for new materials, oriented to radiating floor systems, evaluating different approaches. Samples are submitted to a stepwise, uniform heating. Surface excess temperature is recorded by thermography evaluating thermal inertia. At first, thermal diffusivity has been measured using a modified version of the Flash Method, then applied on a single face, for in situ application. Heat capacity and thermal conductivity have been inferred for each samples by definitions and the independent measure of the volumic mass.

  12. The Future Resources for Eco-building Materials: II.Fly Ash and Coal Waste

    Institute of Scientific and Technical Information of China (English)

    LI Hui; XU Delong

    2009-01-01

    To use fly ash and coal waste effectively,the current technologies for reprocessing and recycling these wastes into eco-building materials were reviewed,such as utilizing fly ash as the component of fly ash cement and low heat cement after the processes of separation,removal of carbon remains and fine comminution,calcining coal waste into kaolin and meta-kaolin with suspension technology,and preparing clinkerless alkali-activated geopolymer materials with fly ash and meta-kaolin.

  13. Design and building of a new experimental setup for testing hydrogen storage materials

    Energy Technology Data Exchange (ETDEWEB)

    Andreasen, Anders

    2005-09-01

    For hydrogen to become the future energy carrier a suitable way of storing hydrogen is needed, especially if hydrogen is to be used in mobile applications such as cars. To test potential hydrogen storage materials with respect to capacity, kinetics and thermodynamics the Materials Research Department has a high pressure balance. However, the drawback of this equipment is, that in order to load samples, exposure towards air is inevitable. This has prompted the design and building of a new experimental setup with a detachable reactor allowing samples to be loaded under protective atmosphere. The purpose of this report is to serve as documentation of the new setup. (au)

  14. Preparation and characterization of phase change material for thermal energy storage in buildings

    Science.gov (United States)

    Lo, Tommy Y.

    2016-04-01

    The paper presents the developing of novel form-stable composite phase change material (PCM) by incorporation of paraffin into lightweight aggregate through vacuum impregnation. The macro-encapsulated Paraffin-lightweight aggregate is a chemical compatible, thermal stable and thermal reliable PCM material for thermal energy storage applications in buildings. The 28 days compressive strength of NWAC using PCM-LWA is 33 - 53 MPa, which has an opportunity for structural purpose. Scanning electronic microscopic images indicated the paraffin can be held inside the porous structure of the aggregate. Thermal performance test showed that the cement paste panel with composite PCM can reduce the indoor temperature.

  15. Seismic soil–structure interaction analysis of a nuclear power plant building founded on soil and in degraded concrete stiffness condition

    Energy Technology Data Exchange (ETDEWEB)

    Farahani, Reza V., E-mail: reza.farahani@rizzoassoc.com; Dessalegn, Tewodros M., E-mail: tewodros.dessalegn@rizzoassoc.com; Vaidya, Nishikant R., E-mail: nish.vaidya@rizzoassoc.com; Bazan-Zurita, Enrique, E-mail: enrique.bazanz@rizzoassoc.com

    2016-02-15

    Highlights: • Three dimensional finite element modeling of a Nuclear Power Plant (NPP) building founded on soil is described. • A simplified technique to consider degraded stiffness of concrete members in seismic analysis of NPP buildings is presented. • The effect of subsurface profiles on the seismic response of a NPP building is investigated. - Abstract: This study describes three-dimensional (3-D) finite element (FE) modeling and seismic Soil-Structure Interaction (SSI) analysis of a Nuclear Power Plant (NPP) Diesel Generator Building (DGB) that is founded on soil in degraded concrete stiffness condition. A new technique is presented that uses two horizontal and vertical FE models to consider the concrete stiffness reduction of NPP buildings subjected to orthogonal ground motion excitations, in which appropriate stiffness reduction factors, based on the input motion orientation, are applied. Seismic SSI analysis is performed for each model separately, and dynamic responses are calculated in the three global directions. The results of the analysis for the two FE models are then combined, using the square-root-of-the-sum-of-squares (SRSS) combination rule. A sensitivity analysis is also performed to investigate the subsurface profile effect on the In-Structure (acceleration) Response Spectra (ISRS) of the building when subjected to site-specific Foundation Input Response Spectra (FIRS) that exhibit high spectral amplifications in the high-frequency range. The sensitivity analysis considers three strain-compatible subsurface profiles that represent Lower-Bound (LB), Best-Estimate (BE), and Upper-Bound (UB) conditions at the DGB site. The sensitivity analysis results indicate that the seismic response of the DGB founded on soil highly depends on the subsurface profile; i.e., each of the LB, BE, and UB subsurface profiles can maximize building seismic response when subjected to FIRS that exhibit high spectral amplifications in the high-frequency range

  16. The relationship between measured moisture conditions and fungal concentrations in water-damaged building materials.

    Science.gov (United States)

    Pasanen, A L; Rautiala, S; Kasanen, J P; Raunio, P; Rantamäki, J; Kalliokoski, P

    2000-06-01

    We determined the moisture levels, relative humidity (RH) or moisture content (MC) of materials, and concentrations of culturable fungi, actinomycetes and total spores as well as a composition of fungal flora in 122 building material samples collected from 18 moisture problem buildings. The purpose of this work was to clarify if the is any correlation between the moisture parameters and microbial levels or generic composition depending on the type of materials and the time passed after a water damage. The results showed an agreement between the concentrations of total spores and culturable fungi for the wood, wood-based and gypsum board samples (r > 0.47). The concentrations of total spores and/or culturable fungi correlated with RH of materials particularly among the wood and insulation materials (r > 0.79), but not usually with MC (r 0.51), while such a relationship could not be observed for the samples taken from dry damage. A wide range of fungal species were found in the samples from ongoing damage, whereas Penicillia and in some cases yeasts dominated the fungal flora in the dry samples. This study indicates that fungal contamination can be evaluated on the basis of moisture measurements of constructions in ongoing damage, but the measurements are not solely adequate for estimation of possible microbial growth in dry damage.

  17. A new alkali-activated steel slag-based cementitious material for photocatalytic degradation of organic pollutant from waste water.

    Science.gov (United States)

    Zhang, Yao Jun; Liu, Li Cai; Xu, Yong; Wang, Ya Chao; Xu, De Long

    2012-03-30

    A new type of Ni,Ca-cementitious material was firstly synthesized via a two-step reaction of alkali-activated steel slag polymerization and ion exchange. The XRF results showed that almost all the Na(+) ions in the matrix of Na,Ca-cementitious material were replaced by Ni(2+) ions at room temperature. The new hydrated products of metahalloysite (Si(2)Al(2)O(5)(OH)(4)) and calcium silicate hydrate (CSH) were formed in the Na,Ca-cementitious material. The diffuse reflectance UV-vis near infrared ray spectrum was blue-shifted due to the strong interaction between Ni(2+) and negative charge of [AlO(4)](5-) tetrahedron in the framework of cementitious material. The Ni,Ca-cementitious material was used as a catalyst for the photocatalytic degradation of methylene blue dye and showed a degradation rate of 94.39% under UV irradiation. The high photocatalytic degradation activity was suggested to be the synergistic effect of the cementitious matrix, Ni(2+) ions and the iron oxides of wustite (FeO) and calcium iron oxide (Ca(2)Fe(2)O(5)) from the steel slag. A probable mechanism of photocatalytic oxidative degradation was proposed.

  18. Testing a model for the critical degree of saturation at freezing of porous building materials

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan De Place

    1996-01-01

    Frost resistance of porous materials can be characterized by the critical degree of saturation, SCR. An experimental determination of SCR is very laborious and therefore only seldom used when testing frost resistance. A theoretical model for prediction of SCR based on fracture mechanics and phase...... geometry of two-phase materials has been developed. The degradation is modelled as being caused by different eigenstrains of the pore phase and the solid phase when freezing, leading to stress concentrations and crack propagation. Calculations are based on porosity, pore size distribution, modulus...... of elasticity, tensile strength, amount of freezable water, thermal expansion coefficients and parameters characterizing the pore structure and its effect on strength, modulus of elasticity and volumetric expansion. For the present, the model assumes non air-entrained homogeneous materials subjected to freeze...

  19. Energy Saving Potentials of Phase Change Materials Applied to Lightweight Building Envelopes

    Directory of Open Access Journals (Sweden)

    Yoon-Bok Seong

    2013-10-01

    Full Text Available Phase change materials (PCMs have been considered as an innovative technology that can reduce the peak loads and heating, ventilating and air conditioning (HVAC energy consumption in buildings. Basically they are substances capable of storing or releasing thermal energy as latent heat. Because the amount of latent heat absorbed or released is much larger than the sensible heat, the application of PCMs in buildings has significant potential to reduce energy consumption. However, because each PCM has its own phase change temperature, which is the temperature at which latent heat is absorbed or released, it is important to use an appropriate PCM for the purpose of building envelope design. Therefore, this paper aims to investigate the energy saving potentials in buildings when various PCMs with different phase change temperatures are applied to a lightweight building envelope by analyzing the thermal load characteristics. As results, the annual heating load increased at every phase change temperature, but the peak heating load decreased by 3.19% with heptadecane (phase change temperature 21 °C, and the lowest indoor temperature increased by 0.86 °C with heptadecane (phase change temperature 21 °C. The annual cooling load decreased by 1.05% with dodecanol (phase change temperature 24 °C, the peak cooling load decreased by 1.30% with octadecane (phase change temperature 29 °C, and the highest indoor temperature dropped by 0.50 °C with octadecane (phase change temperature 29 °C. When the night ventilation was applied to the building HVAC system for better passive cooling performance, the annual cooling load decreased by 9.28% with dodecanol (phase change temperature 24 °C, the peak load decreased by 11.33% with octadecane (phase change temperature 29 °C, and the highest indoor temperature dropped by 0.85 °C with octadecane (phase change temperature 29 °C.

  20. Comparative study of mechanical properties of direct core build-up materials

    Directory of Open Access Journals (Sweden)

    Girish Kumar

    2015-01-01

    Full Text Available Background and Objectives: The strength greatly influences the selection of core material because core must withstand forces due to mastication and para-function for many years. This study was conducted to evaluate certain mechanical properties of commonly used materials for direct core build-up, including visible light cured composite, polyacid modified composite, resin modified glass ionomer, high copper amalgam, and silver cermet cement. Materials and Methods: All the materials were manipulated according to the manufacturer′s recommendations and standard test specimens were prepared. A universal testing machine at different cross-head speed was used to determine all the four mechanical properties. Mean compressive strength, diametral tensile strength, flexural strength, and elastic modulus with standard deviations were calculated. Multiple comparisons of the materials were also done. Results: Considerable differences in compressive strength, diametral tensile strength, and flexural strength were observed. Visible light cured composite showed relatively high compressive strength, diametral tensile strength, and flexural strength compared with the other tested materials. Amalgam showed the highest value for elastic modulus. Silver cermet showed less value for all the properties except for elastic modulus. Conclusions: Strength is one of the most important criteria for selection of a core material. Stronger materials better resist deformation and fracture provide more equitable stress distribution, greater stability, and greater probability of clinical success.

  1. Role of synergy between wear and corrosion in degradation of materials

    Science.gov (United States)

    Azzi, Marwan

    Tribocorrosion is a term used to describe the material degradation due to the combination of electrochemical and tribological processes. Due to a synergetic effect, the material loss can be larger than the sum of the losses due to wear and corrosion acting separately. In this thesis, the synergy of wear and corrosion was investigated for different types of material, namely the Ti-6Al-4V alloy, the SS316L stainless steel coated with a thin film of Diamond Like Carbon (DLC), and the SS301 stainless steel coated with a thin film of chromium silicon nitride (CrSiN). A tribocorrosion apparatus was designed and constructed to conduct wear experiments in corrosive media. Sliding ball-on-plate configuration was used in this design, where the contact between the ball and the specimen is totally immersed in the test electrolyte. The specimen was connected to a potentiostat to control its electrochemical parameters, namely the potential and the current. Electrochemical techniques were used to control the kinetics of corrosion reactions, and therefore it was possible to assess separately the role of corrosion and wear in the total degradation of material, and to evaluate the synergy between them. For Ti-6Al-4V, it was found that the corrosion and tribocorrosion depend strongly on the structure of the material. The alpha-equiaxed microstructure with fine dispersed beta-phase exhibited the best corrosion resistance. The corrosion resistance was found to decrease when the basal plane was preferentially aligned parallel to the surface, which is attributed to a low resistance to charge transfer in the oxide films formed on this plane. On the other hand, when wear and corrosion were involved simultaneously, the oxide layer protecting the substrate against dissolution was mechanically destroyed leading to a high corrosion rate. It was found that the hardness was the most important factor determining the tribocorrosion behavior of the Ti-6Al-4V alloy; samples with high hardness

  2. Build-up material requirements in clinical dosimetry during total body irradiation treatments.

    Science.gov (United States)

    Butson, Martin; Pope, Dane; Haque, Mamoon; Chen, Tom; Song, Guangli; Whitaker, May

    2016-01-01

    Total body irradiation (TBI) treatments are mainly used in a preparative regimen for hematopoietic stem cell (or bone marrow) transplantation. Our standard clinical regimen is a 12 Gy/6 fraction bi-daily technique using 6MV X-rays at a large extended source to surface distance (SSD). This work investigates and quantifies the dose build-up characteristics and thus the requirements for bolus used for in vivo dosimetry for TBI applications. Percentage dose build-up characteristics of photon beams have been investigated at large extended SSDs using ionization chambers and Gafchromic film. Open field measurements at different field sizes and with differing scatter conditions such as the introduction of standard Perspex scattering plates at different distances to the measurement point were made in an effort to determine the required bolus/build-up material required for accurate determination of applied dose. Percentage surface dose values measured for open fields at 300 cm SSD were found to range from 20% up to 65.5% for fields 5 cm × 5 cm to 40 cm × 40 cm, respectively. With the introduction of 1 cm Perspex scattering plates used in TBI treatments, the surface dose values increased up to 83-90% (93-97% at 1 mm depth), depending on the position of the Perspex scattering plate compared to the measurement point. Our work showed that at least 5 mm water equivalent bolus/scatter material should be placed over the EBT3 film for accurate dose assessment for TBI treatments. Results also show that a small but measurable decrease in measured dose occurred with 5 mm water equivalent thick bolus material of areas '3 cm(2). As such, we recommend that 3 cm × 3 cm × 5 mm bolus build-up is the smallest size that should be placed over EBT3 Gafchromic film when used for accurate in vivo dosimetry for TBI applications.

  3. Emissions of volatile organic compounds from building materials and consumer products

    Science.gov (United States)

    Wallace, Lance A.; Pellizzari, Edo; Leaderer, Brian; Zelon, Harvey; Sheldon, Linda

    EPA's TEAM Study of personal exposure to volatile organic compounds (VOC) in air and drinking water of 650 residents of seven U.S. cities resulted in the identification of a number of possible sources encountered in peoples' normal daily activities and in their homes. A follow-up EPA study of publicaccess buildings implicated other potential sources of exposure. To learn more about these potential sources, 15 building materials and common consumer products were analyzed using a headspace technique to detect organic emissions and to compare relative amounts. About 10-100 organic compounds were detected offgassing from each material. Four mixtures of materials were then chosen for detailed study: paint on sheetrock; carpet and carpet glue; wallpaper and adhesives; cleansers and a spray pesticide. The materials were applied as normally used, allowed to age 1 week (except for the cleansers and pesticides, which were used normally during the monitoring period), and placed in an environmentally controlled chamber. Organic vapors were collected on Tenax-GC over a 4-h period and analyzed by GC-MS techniques. Emission rates and chamber concentrations were calculated for 17 target chemicals chosen for their toxic, carcinogenic or mutagenic properties. Thirteen of the 17 chemicals were emitted by one or more of the materials. Elevated concentrations of chloroform, carbon tetrachloride, 1,1,1-trichloroethane, n-decane, n-undecane, p-dichlorobenzene, 1,2-dichloroethane and styrene were produced by the four mixtures of materials tested. For some chemicals, these amounts were sufficient to account for a significant fraction of the elevated concentrations observed in previous indoor air studies. We conclude that common materials found in nearly every home and place of business may cause elevated exposures to toxic chemicals.

  4. Enzymes for Degradation of Energetic Materials and Demilitarization of Explosives Stockpiles - SERDP Annual (Interim) Report, 12/98

    Energy Technology Data Exchange (ETDEWEB)

    Shah, M.M.

    1999-01-18

    The current stockpile of energetic materials requiring disposal contains about half a million tons. Through 2001, over 2.1 million tons are expected to pass through the stockpile for disposal. Safe and environmentally acceptable methods for disposing of these materials are needed. This project is developing safe, economical, and environmentally sound processes using biocatalyst (enzymes) to degrade energetic materials and to convert them into economically valuable products. Alternative methods for destroying these materials are hazardous, environmentally unacceptable, and expensive. These methods include burning, detonation, land and sea burial, treatment at high temperature and pressure, and treatment with harsh chemicals. Enzyme treatment operates at room temperature and atmospheric pressure in a water solution.

  5. Green Sharing: The Proposed Criteria in Green Building Standards to Promote the Usage of Natural Handicrafts in Building Materials

    Directory of Open Access Journals (Sweden)

    Krasae-In Aracha

    2016-01-01

    Full Text Available Sustainable development has been a great challenge to the building and construction industry for decades. There have been many initiatives and attempts to create sustainability for the industry through the concept of the Green Building certificate in order to reduce the impact to environment and society while promoting better living conditions of the people involved in the project. This paper aims to examine all three aspects of sustainability; economy, environment and society, in the building and construction industry by proposing new criteria for the green building certificate. This will create opportunities for the community based handicraft building products to be specified and purchased to be used in the modern building and construction industry and share the economic value to the community.

  6. Natural activities of {sup 238}U, {sup 232}Th and {sup 40}K in building materials

    Energy Technology Data Exchange (ETDEWEB)

    Ibrahim, N. [Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia)

    1999-05-01

    Seven kinds of building materials were analysed for {sup 238}U, {sup 232}Th and {sup 40}K using a direct {gamma}-counting method. The activity concentrations measured for {sup 238}U (30-448 Bq kg{sup -1}) and {sup 40}K (328-7541 Bq kg{sup -1}) were greater than the world average activity for soil (25 and 370 Bq kg{sup -1}, respectively) for all building materials analysed, while the activity concentrations of {sup 232}Th were found to exceed the average of 25 Bq kg{sup -1} (soil) for red-clay brick (51 Bq kg{sup -1}) and ceiling asbestos sheet materials (162 Bq kg{sup -1}). The calculated Ra equivalent activities (Ra{sub eq}) for all materials are higher than the world average value for soil (89 Bq kg{sup -1}). For red-clay brick and ceiling asbestos, the Ra{sub eq} values are found to exceed the limit of 370 Bq kg{sup -1}, equivalent to a {gamma}-dose of 1.5 mSv yr{sup -1}. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  7. Review of the use of phase change materials (PCMs in buildings with reinforced concrete structures

    Directory of Open Access Journals (Sweden)

    Pons, O.

    2014-09-01

    Full Text Available Phase change materials are capable of storing and releasing energy in the form of heat in determined temperature ranges, so to increase a building’s thermal inertia, stabilize its indoor temperatures and reduce its energetic demand. Therefore, if we used these materials we could have more energetically efficient buildings. Nevertheless, are these materials most appropriate to be used in buildings? Could the incorporation of phase change materials in buildings with concrete structures be generalized? This article aims to carry out a review of these phase change materials from construction professionals’ points of view, study their applications for buildings with reinforced concrete structures and the key points for these applications, draw conclusions and provide recommendations useful for all professionals within the sector who are considering the application of these materials.Los materiales de cambio de fase son capaces de almacenar y liberar energía en forma de calor en un determinando rango de temperaturas, y así aumentar la inercia térmica de un edificio, estabilizar las temperaturas en el interior y reducir la demanda energética. En consecuencia, si utilizáramos estos materiales podríamos tener un parque de edificios más eficientes energéticamente. No obstante, ¿estos materiales son apropiados para usarse en edificios? ¿Se podría generalizar la incorporación de materiales de cambio de fase en edificios con estructuras de hormigón? Este artículo tiene como objetivos hacer una revisión del estado del arte de estos materiales de cambio de fase desde el punto de vista de los profesionales de la construcción, estudiar las aplicaciones en edificios con estructuras de hormigón armado y los puntos clave para estas aplicaciones, extraer conclusiones y recomendaciones útiles para los profesionales del sector que se planteen la utilización de estos materiales.

  8. Fundamental degradation mechanisms of layered oxide Li-ion battery cathode materials: Methodology, insights and novel approaches

    Energy Technology Data Exchange (ETDEWEB)

    Hausbrand, R., E-mail: hausbrand@surface.tu-darmstadt.de; Cherkashinin, G.; Ehrenberg, H.; Gröting, M.; Albe, K.; Hess, C.; Jaegermann, W.

    2015-02-15

    Graphical abstract: - Highlights: • Description of recent in operando and in situ analysis methodology. • Surface science approach using photoemission for analysis of cathode surfaces and interfaces. • Ageing and fatigue of layered oxide Li-ion battery cathode materials from the atomistic point of view. • Defect formation and electronic structure evolution as causes for cathode degradation. • Significance of interfacial energy alignment and contact potential for side reactions. - Abstract: This overview addresses the atomistic aspects of degradation of layered LiMO{sub 2} (M = Ni, Co, Mn) oxide Li-ion battery cathode materials, aiming to shed light on the fundamental degradation mechanisms especially inside active cathode materials and at their interfaces. It includes recent results obtained by novel in situ/in operando diffraction methods, modelling, and quasi in situ surface science analysis. Degradation of the active cathode material occurs upon overcharge, resulting from a positive potential shift of the anode. Oxygen loss and eventual phase transformation resulting in dead regions are ascribed to changes in electronic structure and defect formation. The anode potential shift results from loss of free lithium due to side reactions occurring at electrode/electrolyte interfaces. Such side reactions are caused by electron transfer, and depend on the electron energy level alignment at the interface. Side reactions at electrode/electrolyte interfaces and capacity fade may be overcome by the use of suitable solid-state electrolytes and Li-containing anodes.

  9. Leveraging "raw materials" as building blocks and bioactive signals in regenerative medicine.

    Science.gov (United States)

    Renth, Amanda N; Detamore, Michael S

    2012-10-01

    Components found within the extracellular matrix (ECM) have emerged as an essential subset of biomaterials for tissue engineering scaffolds. Collagen, glycosaminoglycans, bioceramics, and ECM-based matrices are the main categories of "raw materials" used in a wide variety of tissue engineering strategies. The advantages of raw materials include their inherent ability to create a microenvironment that contains physical, chemical, and mechanical cues similar to native tissue, which prove unmatched by synthetic biomaterials alone. Moreover, these raw materials provide a head start in the regeneration of tissues by providing building blocks to be bioresorbed and incorporated into the tissue as opposed to being biodegraded into waste products and removed. This article reviews the strategies and applications of employing raw materials as components of tissue engineering constructs. Utilizing raw materials holds the potential to provide both a scaffold and a signal, perhaps even without the addition of exogenous growth factors or cytokines. Raw materials contain endogenous proteins that may also help to improve the translational success of tissue engineering solutions to progress from laboratory bench to clinical therapies. Traditionally, the tissue engineering triad has included cells, signals, and materials. Whether raw materials represent their own new paradigm or are categorized as a bridge between signals and materials, it is clear that they have emerged as a leading strategy in regenerative medicine. The common use of raw materials in commercial products as well as their growing presence in the research community speak to their potential. However, there has heretofore not been a coordinated or organized effort to classify these approaches, and as such we recommend that the use of raw materials be introduced into the collective consciousness of our field as a recognized classification of regenerative medicine strategies.

  10. Amplitude-sensitive modulation thermography to measure moisture in building materials

    Science.gov (United States)

    Wild, Walter; Buescher, Konstantin A.; Wiggenhauser, Herbert

    1998-03-01

    There have been reports about moisture detection in building walls by reflective IR-thermography. Typically, only limited results could be obtained because of the emission coefficient variations, leaking radiation or inhomogeneous illumination of the object. In addition, the quantitative relation between remission spectra and the moisture has often been unclear. Reflectometry uses constant excitation illumination which is recorded by the IR camera. With the use of the 'lock-in-technology' a low frequency modulated signal of an IR radiation source is coupled with the thermo camera and a frequency and phase sensitive signal from the thermal images can be derived. The advantage is, that emission coefficient dependencies are eliminated and that leaking radiation does not have any influence on the measured signal. The selective water measurement is possible, because there is an interference filter mounted in front of the radiator which has its transmission maximum at the wavelength of an absorption band of water. The area investigated is therefore illuminated under well defined circumstances and quantitative moisture measurement on the surface of building materials becomes a possibility. The illumination modulation is done with a sine wave to facilitate the calculation of the temporal intensity behavior of the amplitude signal. Subsequently, the amplitude image is used to determine the distribution and the level of moisture quantitatively. Point measurements in the laboratory were carried out on several building materials with changing moisture levels. It could be shown that this method successfully eliminates disturbing contributions to the measured signal like surface effects or leaking radiation.

  11. Data Collection Handbook to Support Modeling Impacts of Radioactive Material in Soil and Building Structures

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Charley [Argonne National Lab. (ANL), Argonne, IL (United States); Kamboj, Sunita [Argonne National Lab. (ANL), Argonne, IL (United States); Wang, Cheng [Argonne National Lab. (ANL), Argonne, IL (United States); Cheng, Jing-Jy [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-09-01

    This handbook is an update of the 1993 version of the Data Collection Handbook and the Radionuclide Transfer Factors Report to support modeling the impact of radioactive material in soil. Many new parameters have been added to the RESRAD Family of Codes, and new measurement methodologies are available. A detailed review of available parameter databases was conducted in preparation of this new handbook. This handbook is a companion document to the user manuals when using the RESRAD (onsite) and RESRAD-OFFSITE code. It can also be used for RESRAD-BUILD code because some of the building-related parameters are included in this handbook. The RESRAD (onsite) has been developed for implementing U.S. Department of Energy Residual Radioactive Material Guidelines. Hydrogeological, meteorological, geochemical, geometrical (size, area, depth), crops and livestock, human intake, source characteristic, and building characteristic parameters are used in the RESRAD (onsite) code. The RESRAD-OFFSITE code is an extension of the RESRAD (onsite) code and can also model the transport of radionuclides to locations outside the footprint of the primary contamination. This handbook discusses parameter definitions, typical ranges, variations, and measurement methodologies. It also provides references for sources of additional information. Although this handbook was developed primarily to support the application of RESRAD Family of Codes, the discussions and values are valid for use of other pathway analysis models and codes.

  12. Probabilistic Structural Analysis and Reliability Using NESSUS With Implemented Material Strength Degradation Model

    Science.gov (United States)

    Bast, Callie C.; Jurena, Mark T.; Godines, Cody R.; Chamis, Christos C. (Technical Monitor)

    2001-01-01

    This project included both research and education objectives. The goal of this project was to advance innovative research and education objectives in theoretical and computational probabilistic structural analysis, reliability, and life prediction for improved reliability and safety of structural components of aerospace and aircraft propulsion systems. Research and education partners included Glenn Research Center (GRC) and Southwest Research Institute (SwRI) along with the University of Texas at San Antonio (UTSA). SwRI enhanced the NESSUS (Numerical Evaluation of Stochastic Structures Under Stress) code and provided consulting support for NESSUS-related activities at UTSA. NASA funding supported three undergraduate students, two graduate students, a summer course instructor and the Principal Investigator. Matching funds from UTSA provided for the purchase of additional equipment for the enhancement of the Advanced Interactive Computational SGI Lab established during the first year of this Partnership Award to conduct the probabilistic finite element summer courses. The research portion of this report presents the cumulation of work performed through the use of the probabilistic finite element program, NESSUS, Numerical Evaluation and Structures Under Stress, and an embedded Material Strength Degradation (MSD) model. Probabilistic structural analysis provided for quantification of uncertainties associated with the design, thus enabling increased system performance and reliability. The structure examined was a Space Shuttle Main Engine (SSME) fuel turbopump blade. The blade material analyzed was Inconel 718, since the MSD model was previously calibrated for this material. Reliability analysis encompassing the effects of high temperature and high cycle fatigue, yielded a reliability value of 0.99978 using a fully correlated random field for the blade thickness. The reliability did not change significantly for a change in distribution type except for a change in

  13. Materials degradation in PVC medical devices, DEHP leaching and neonatal outcomes.

    Science.gov (United States)

    Latini, G; Ferri, M; Chiellini, F

    2010-01-01

    Polymeric materials play a key role in the production of medical and clinical devices thanks to their special features such as flexibility, easy processing and good price/performance ratio. Among the different polymeric matrixes, one of the most used is Poly(vinyl chloride) (PVC). At room temperature PVC is hard and brittle, thus great amounts (40-50%) of phthalate esters that act as plasticizers are added to the polymer to make it flexible and appropriate for medical use. Di-(2-ethylhexyl)-phthalate (DEHP) is the most widely used plasticizer in PVC medical devices. However, DEHP is not chemically bound to PVC and migrates from medical devices with time and use. The potential for DEHP to produce adverse effects in humans has been the subject of considerable discussion and debate in the scientific community. In particular, newborns in the new environment have to be considered at particularly increased risk, because of their small body size and the multiple medical device-related to the DEHP exposure. The major factors determining the degree to which DEHP migrates from medical devices are temperature, amount of DEHP in the device, storage time, shaking of the device while in contact with the medical solutions and degree of PVC degradation.

  14. In vitro Cellulose Rich Organic Material Degradation by Cellulolytic Streptomyces albospinus (MTCC 8768

    Directory of Open Access Journals (Sweden)

    Pinky Prasad

    2012-09-01

    Full Text Available Aims: Cellulosic biomass is the only foreseeable sustainable source of fuels and is also one of the dominating waste materials in nature resulting from human activities. Keeping in view the environmental problems like disposal of large volumes of cellulosic wastes and shortage of fossil fuel in the world, the main aim of the present investigation was to characterize and study the cellulolytic activity of Streptomyces albospinus (MTCC 8768, isolated from municipal wastes, on natural cellulosic substrates viz. straw powder, wood powder and finely grated vegetable peels.Methodology and Result: Stanier’s Basal broth with 100 mg of each of the substrates was inoculated separately with S. albospinus (MTCC No. 8768 and incubated at 37 °C for 8 days. The cellulosic substrates were re-weighed at an interval of 2 days and the difference between the initial weight and the final weight gave the amount of substratesdegraded by the isolate. It was observed that maximum degradation was observed in the grated vegetable peels (64 mg followed by straw powder (38 mg and wood powder (28 mg over a period of 8 days.Conclusion, significance and impact of study: By the selection of efficient cellulolytic microorganisms and cost-effective operational techniques, the production of useful end products from the biodegradation of the low cost enormous stock of cellulose in nature can be very beneficial.

  15. Biodegradability of biodegradable/degradable plastic materials under aerobic and anaerobic conditions.

    Science.gov (United States)

    Mohee, R; Unmar, G D; Mudhoo, A; Khadoo, P

    2008-01-01

    A study was conducted on two types of plastic materials, Mater-Bi Novamont (MB) and Environmental Product Inc. (EPI), to assess their biodegradability under aerobic and anaerobic conditions. For aerobic conditions, organic fractions of municipal solid wastes were composted. For the anaerobic process, anaerobic inoculum from a wastewater treatment plant was used. Cellulose filter papers (CFP) were used as a positive control for both mediums. The composting process was monitored in terms of temperature, moisture and volatile solids and the biodegradation of the samples were monitored in terms of mass loss. Monitoring results showed a biodegradation of 27.1% on a dry basis for MB plastic within a period of 72 days of composting. Biodegradability under an anaerobic environment was monitored in terms of biogas production. A cumulative methane gas production of 245 ml was obtained for MB, which showed good degradation as compared to CFP (246.8 ml). However, EPI plastic showed a cumulative methane value of 7.6 ml for a period of 32 days, which was close to the blank (4.0 ml). The EPI plastic did not biodegrade under either condition. The cumulative carbon dioxide evolution after 32 days was as follows: CFP 4.406 cm3, MB 2.198 cm3 and EPI 1.328 cm3. The cumulative level of CO2 varying with time fitted sigmoid type curves with R2 values of 0.996, 0.996 and 0.995 for CFP, MB and EPI, respectively.

  16. Numerical study of the thermal degradation of isotropic and anisotropic polymeric materials

    Energy Technology Data Exchange (ETDEWEB)

    Soler, E. [Departamento de Lenguajes y Ciencias de la Computacion, ETSI Informatica, Universidad de Malaga, 29071 Malaga (Spain); Ramos, J.I. [Room I-320-D, ETS Ingenieros Industriales, Universidad de Malaga, Plaza El Ejido, s/n, 29013 Malaga (Spain)

    2005-08-01

    The thermal degradation of two-dimensional isotropic, orthotropic and anisotropic polymeric materials is studied numerically by means of a second-order accurate (in both space and time) linearly implicit finite difference formulation which results in linear algebraic equations at each time step. It is shown that, for both isotropic and orthotropic composites, the monomer mass diffusion tensor plays a role in initiating the polymerization kinetics, the formation of a polymerization kernel and the initial front propagation, whereas the later stages of the polymerization are nearly independent of the monomer mass diffusion tensor. In anisotropic polymeric composites, it has been found that the monomer mass diffusion tensor plays a paramount role in determining the initial stages of the polymerization and the subsequent propagation of the polymerization front, the direction and speed of propagation of which are found to be related to the principal directions of both the monomer mass and the heat diffusion tensors. It is also shown that the polymerization time and temperatures depend strongly on the anisotropy of the mass and heat diffusion tensors. (authors)

  17. DEVELOPMENT OF RHEOLOGY OF ROAD-BUILDING MATERIALS FOR PERFECTION OF THEIR COMPACTION TECHNOLOGY

    Directory of Open Access Journals (Sweden)

    Vl. P. Podolskу

    2012-04-01

    Full Text Available Problem statement. The main problems of improving the quality and effectiveness of compaction of soil subgrade and road asphalt mixtures are discussed. Technology of road-building materials compaction can be improved by developing and using the rheological approach in the describing and studying changes in physical and mechanical parameters of materials, when the rheological properties of compacted material is closely connected to the nature of a force action applied to it.Results. The principles of designing rheological models of soil subgrade and road asphalt mixtures are formulated, based on which a model is suggested of the creep process of road construction materials using the theory of hereditary creep of elastic-visco-plastic materials. The choice of exponential and power influence functions is explained, the application of which will improve the accuracy of the physical and mechanical properties of compacted materials. Conclusions. Development of rheology road soils and asphalt mixtures reveals significant new laws in the development of deformation of compacted layers of road construction materials in the way of improving the compaction technology.

  18. Survey of degradation modes of candidate materials for high-level radioactive-waste disposal containers

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, J.C.; Van Konynenburg, R.A.; McCright, R.D. (Lawrence Livermore National Lab., CA (USA)); Bullen, D.B. (Science and Engineering Associates, Inc., Pleasanton, CA (USA))

    1988-04-01

    Three iron- to nickel-based austenitic alloys (Types 304L and 316L stainless steels and Alloy 825) are being considered as candidate materials for the fabrication of high-level radioactive-waste containers. Waste will include fuel assemblies from reactors as well as high-level waste in borosilicate glass forms, and will be sent to the prospective repository at Yucca Mountain, Nevada. The decay of radionuclides in the repository will result in the generation of substantial heat and in fluences of gamma radiation. Container materials may undergo any of several modes of degradation in this environment, including atmospheric oxidation; uniform aqueous phase corrosion; pitting; crevice corrosion; sensitization and intergranular stress corrosion cracking (IGSCC); and transgranular stress corrosion cracking (TGSCC). This report is an analysis of data relevant to the pitting, crevice corrosion, and stress corrosion cracking (SCC) of the three austenitic candidate alloys. The candidates are compared in terms of their susceptibilities to these forms of corrosion. Although all three candidates have demonstrated pitting and crevice corrosion in chloride-containing environments, Alloy 825 has the greatest resistance to these types of localized corrosion (LC); such resistance is important because pits can penetrate the metal and serve as crack initiation sites. Both Types 304L and 316L stainless steels are susceptible to SCC in acidic chloride media. In contrast, SCC has not been documented in Alloy 825 under comparable conditions. Gamma radiation has been found to enhance SCC in Types 304 and 304L stainless steels, but it has no detectable effect on the resistance of Alloy 825 to SCC. Furthermore, while the effects of microbiologically induced corrosion have been observed for 300-series stainless steels, nickel-based alloys such as Alloy 825 seem to be immune to such problems. 211 refs., 49 figs., 10 tabs.

  19. Sequestering carbon dioxide in industrial polymers: Building materials for the 21st century

    Energy Technology Data Exchange (ETDEWEB)

    Molton, P.M.; Nelson, D.A.

    1993-06-01

    This study was undertaken to determine the possibility of developing beneficial uses for carbon dioxide as a key component for a large-volume building product. Such a use may provide an alternative to storing the gas in oceanic sinks or clathrates as a way to slow the rate of global warming. The authors investigated the concept that carbon dioxide might be used with other chemicals to make carbon-dioxide-based polymers which would be lightweight, strong, and economical alternatives to some types of wood and silica-based building materials. As a construction-grade material, carbon dioxide would be fixed in a solid, useful form where it would not contribute to global warming. With the probable imposition of a fuel carbon tax in industrialized countries, this alternative would allow beneficial use of the carbon dioxide and could remove it from the tax basis if legislation were structured appropriately. Hence, there would be an economic driver towards the use of carbon-dioxide-based polymers which would enhance their future applications. Information was obtained through literature searches and personal contacts on carbon dioxide polymers which showed that the concept (1) is technically feasible, (2) is economically defensible, and (3) has an existing industrial infrastructure which could logically develop it. The technology exists for production of building materials which are strong enough for use by industry and which contain up to 90% by weight of carbon dioxide, both chemically and physically bound. A significant side-benefit of using this material would be that it is self-extinguishing in case of fire. This report is the first stage in the investigation. Further work being proposed will provide details on costs, specific applications and volumes, and potential impacts of this technology.

  20. Final report for the designed synthesis of controlled degradative materials LDRD

    Energy Technology Data Exchange (ETDEWEB)

    LOY,DOUGLAS A.; ULIBARRI,TAMARA A.; CURRO,JOHN G.; SAUNDERS,R.; DERZON,DORA K.; GUESS,TOMMY R.; BAUGHER,B.M.

    2000-02-01

    The main goal of this research was to develop degradable systems either by developing weaklink-containing polymers or identifying commercial polymeric systems which are easily degraded. In both cases, the degradation method involves environmentally friendly chemistries. The weaklinks are easily degradable fragments which are introduced either randomly or regularly in the polymer backbone or as crosslinking sites to make high molecular weight systems via branching. The authors targeted three general application areas: (1) non-lethal deterrents, (2) removable encapsulants, and (3) readily recyclable/environmentally friendly polymers for structural and thin film applications.

  1. Some Materials Degradation Issues in the U.S. High-Level Nuclear Waste Repository Study (The Yucca Mountain Project)

    Energy Technology Data Exchange (ETDEWEB)

    F. Hua; P. Pasupathi; N. Brown; K. Mon

    2005-09-19

    The safe disposal of radioactive waste requires that the waste be isolated from the environment until radioactive decay has reduced its toxicity to innocuous levels for plants, animals, and humans. All of the countries currently studying the options for disposing of high-level nuclear waste (HLW) have selected deep geologic formations to be the primary barrier for accomplishing this isolation. In U.S.A., the Nuclear Waste Policy Act of 1982 (as amended in 1987) designated Yucca Mountain in Nevada as the potential site to be characterized for high-level nuclear waste (HLW) disposal. Long-term containment of waste and subsequent slow release of radionuclides into the geosphere will rely on a system of natural and engineered barriers including a robust waste containment design. The waste package design consists of a highly corrosion resistant Ni-based Alloy 22 cylindrical barrier surrounding a Type 316 stainless steel inner structural vessel. The waste package is covered by a mailbox-shaped drip shield composed primarily of Ti Grade 7 with Ti Grade 24 structural support members. The U.S. Yucca Mountain Project has been studying and modeling the degradation issues of the relevant materials for some 20 years. This paper reviews the state-of-the-art understanding of the degradation processes based on the past 20 years studies on Yucca Mountain Project (YMP) materials degradation issues with focus on interaction between the in-drift environmental conditions and long-term materials degradation of waste packages and drip shields within the repository system during the 10,000 years regulatory period. This paper provides an overview of the current understanding of the likely degradation behavior of the waste package and drip shield in the repository after the permanent closure of the facility. The degradation scenario discussed in this paper include aging and phase instability, dry oxidation, general and localized corrosion, stress corrosion cracking and hydrogen induced

  2. Monitoring of Water Content in Building Materials Using a Wireless Passive Sensor

    Directory of Open Access Journals (Sweden)

    Goran Stojanović

    2010-04-01

    Full Text Available This paper describes an innovative design of a wireless, passive LC sensor and its application for monitoring of water content in building materials. The sensor was embedded in test material samples so that the internal water content of the samples could be measured with an antenna by tracking the changes in the sensor’s resonant frequency. Since the dielectric constant of water was much higher compared with that of the test samples, the presence of water in the samples increased the capacitance of the LC circuit, thus decreasing the sensor’s resonant frequency. The sensor is made up of a printed circuit board in one metal layer and water content has been determined for clay brick and autoclaved aerated concrete block, both widely used construction materials. Measurements were conducted at room temperature using a HP-4194A Impedance/Gain-Phase Analyzer instrument.

  3. Characterization of magnetic material in the mound-building termite Macrotermes gilvus in Southeast Asia

    Energy Technology Data Exchange (ETDEWEB)

    Esa, Mohammad Faris Mohammad; Hassan, Ibrahim Haji [School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Selangor (Malaysia); Rahim, Faszly; Hanifah, Sharina Abu [School of Environmental Scieces and Natural Resources Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Selangor (Malaysia)

    2015-09-25

    Magnetic material such as magnetite are known as particles that respond to external magnetic field with their ferromagnetic properties as they are believed contribute to in responding to the geomagnetic field. These particles are used by terrestrial animals such as termites for navigation and orientation. Since our earth react as giant magnetic bar, the magnitude of this magnetic field present by intensity and direction (inclination and direction). The magnetic properties and presence of magnetite in termites Macrotermes gilvus, common mound-building termite were tested. M. gilvus termites was tested with a Vibrating Sample Magnetometer VSM to determine the magnetic properties of specimen. The crushed body sample was characterized with X-Ray Diffraction XRD to show the existent of magnetic material (magnetite) in the specimens. Results from VSM indicate that M. gilvus has diamagnetism properties. The characterization by XRD shows the existent of magnetic material in our specimen in low concentration.

  4. Evidence on dynamic effects in the water content – water potential relation of building materials

    DEFF Research Database (Denmark)

    Scheffler, Gregor Albrecht; Plagge, Rudolf

    2008-01-01

    the required material functions, i.e. the moisture storage characteristic and the liquid water conductivity, from measured basic properties. The current state of the art in material modelling as well as the corresponding transport theory implies that the moisture transport function is unique...... and that the moisture storage characteristic is process dependent with varying significance for the numerical simulation. On the basis of different building materials, a comprehensive instantaneous profile measurement study has been accomplished. Profiles of water content and relative humidity were obtained during...... a series of adsorption and desorption processes. The data provides clear evidence that the water content – water potential relationship is not only dependent on the process history, but also on the process dynamics. The higher moisture potential gradients were induced, the larger was the deviation between...

  5. Quality Improvement of Granular Wastes-The Effective Way to Recycle Secondary Raw Building Materials

    Institute of Scientific and Technical Information of China (English)

    XING Wei-hong; Charles Hendriks; Alex Fraaij; Peter Rem

    2004-01-01

    Granular wastes have negative effects on the environment due to contamination. On the other hand, stony components in granular wastes have a potential good perspectives for utilization in civil engineering works as secondary raw building materials. To reuse such materials without environmental risks, all contaminants must be removed or reduced to an acceptable level. Therefore liberation of materials is an important step in waste treatment. For this purpose, separation and cleansing techniques are suitable. Based on the analysis of contaminants in wastes, it is discussed how to select suitable techniques. The rules for technique selection and processes for quality improvement are set up. To evaluate the environmental quality and technical quality of output products, it is necessary to check leaching behaviours and physical properties.

  6. The Baroque monuments of Modica (Eastern Sicily): assessment of causes of chromatic alteration of stone building materials

    Science.gov (United States)

    Belfiore, Cristina M.; La Russa, Mauro F.; Pezzino, Antonino; Campani, Elisa; Casoli, Antonella

    2010-09-01

    The Baroque monuments of several cities in eastern Sicily, built of local calcarenitic stone, are often subjected to conservation treatments, since they undergo many forms of alteration and degradation which can cause significant damage. However, a recent study of these building materials (Barone et al. in Environ. Geol. 54:1501, 2008) has demonstrated that some protective products, once applied, cause irreversible chromatic alterations. The façades of the monuments of the historic city centre of Modica are typically creamy yellow in colour, sometimes varying slightly due to the use of various pigments, such as clayey and gypseous earths (La Russa et al. in Appl. Phys. A 92:185, 2008). However, in some cases, these nuances are lost due to the application of protective products. This work provides a petrographic and colorimetric characterisation of the calcarenitic stone used to create the façades of the churches of S. Pietro, S. Maria del Soccorso and S. Maria dell’Annunziata in Modica, also by comparisons with locally quarried samples. In addition, it aims to identify protective substances which may have been used during previous restoration work. Analytical techniques included polarising optical microscopy, spectrophotometric colorimetric tests, Fourier-transform infrared spectroscopy (FTIR) and gas chromatography coupled with mass spectrometry (GC-MS).

  7. Natural radioactivity in granite stones used as building materials in Iran.

    Science.gov (United States)

    Asgharizadeh, F; Abbasi, A; Hochaghani, O; Gooya, E S

    2012-04-01

    Due to increasing concern about environmental radiological protection, specific radioactivity concentrations of (226)Ra, (232)Th and (40)K in different types of commonly used granite stone samples collected from the Tehran city of Iran have been determined by means of a high-resolution HPGe gamma-spectroscopy system. The activity concentrations of (232)Th, (226)Ra and (40)K in the selected granite samples ranged from 18 to 178, 6 to 160 and 556 to 1539 Bq kg(-1), respectively. The radium equivalent activities (Ra(eq)) are lower than the limit of 370 Bq kg(-1) set by NEA-OECD [Nuclear Energy Agency. Exposure to radiation from natural radioactivity in building materials. Report by NEA Group of Experts. OECD (1979)], except in two samples. The internal hazard indexes have been found well below the acceptable limit in most of the samples. Five samples of investigated commercial granite stones do not satisfy the safety criterion illustrated by UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiation. Exposure from natural sources of radiation. Report to the General Assembly (1993). Applying dose criteria recently recommended by the EC [European Commission Report on Radiological Protection Principles Concerning the Natural Radioactivity of Building Materials. Radiation Protection 112 (1999)] for superficial materials, all investigated samples meet the exemption dose limit of 0.3 mSv y(-1).

  8. C-Depth Method to Determine Diffusion Coefficient and Partition Coefficient of PCB in Building Materials.

    Science.gov (United States)

    Liu, Cong; Kolarik, Barbara; Gunnarsen, Lars; Zhang, Yinping

    2015-10-20

    Polychlorinated biphenyls (PCBs) have been found to be persistent in the environment and possibly harmful. Many buildings are characterized with high PCB concentrations. Knowledge about partitioning between primary sources and building materials is critical for exposure assessment and practical remediation of PCB contamination. This study develops a C-depth method to determine diffusion coefficient (D) and partition coefficient (K), two key parameters governing the partitioning process. For concrete, a primary material studied here, relative standard deviations of results among five data sets are 5%-22% for K and 42-66% for D. Compared with existing methods, C-depth method overcomes the inability to obtain unique estimation for nonlinear regression and does not require assumed correlations for D and K among congeners. Comparison with a more sophisticated two-term approach implies significant uncertainty for D, and smaller uncertainty for K. However, considering uncertainties associated with sampling and chemical analysis, and impact of environmental factors, the results are acceptable for engineering applications. This was supported by good agreement between model prediction and measurement. Sensitivity analysis indicated that effective diffusion distance, contacting time of materials with primary sources, and depth of measured concentrations are critical for determining D, and PCB concentration in primary sources is critical for K.

  9. The influence of rainwater composition on the conservation state of cementitious building materials

    Energy Technology Data Exchange (ETDEWEB)

    Morillas, Héctor, E-mail: hector.morillas@ehu.es [Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country UPV/EHU, P.O. Box 644, 48080 Bilbao, Basque Country (Spain); Marcaida, Iker [Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country UPV/EHU, P.O. Box 644, 48080 Bilbao, Basque Country (Spain); Maguregui, Maite [Department of Analytical Chemistry, Faculty of Pharmacy, University of the Basque Country UPV/EHU, P.O. Box 450, 01080 Vitoria-Gasteiz, Basque Country (Spain); Carrero, Jose Antonio; Madariaga, Juan Manuel [Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country UPV/EHU, P.O. Box 644, 48080 Bilbao, Basque Country (Spain)

    2016-01-15

    Rainwater is one of the main pollution tracers around the world. There are many reasons that can explain the presence of high concentrations of certain hazardous elements (HEs) in the rainwater (traffic, marine port activities, industry, etc.). In this work, rainwater samples were collected at six different locations in the Metropolitan Bilbao (Basque Country, north of Spain) during November 2014. HE concentrations were determined by means of inductively coupled plasma mass spectrometry (ICP-MS) and anions by ion chromatography. The pH and redox potential values on these samples were also assessed. According to the obtained results, different trends along the estuary of Bilbao have been observed. To corroborate some hypothesis, thermodynamic simulations and correlation analyses were also carried out using quantitative data. These trends are closely related to the surrounding pollution and marine influence. Finally, in order to ascertain the influence of the Metropolitan Bilbao rainwater on buildings materials, a recent construction was characterized. Using techniques such as Scanning Electron Microscopy coupled with Energy Dispersive X-Ray Spectroscopy (SEM–EDS) and Raman Spectroscopy, different types of sulfates and nitrates were observed. - Highlights: • Rainwater from six sampling points along Nervion River (Bilbao, Spain) were analyzed. • Ion chromatography, ICP-MS and chemometrics were used for the rainwater analyses. • The interaction between wet depositions and building materials was studied. • Cementitious materials were analyzed using µ-Raman spectroscopy and SEM–EDS.

  10. Human Perception, SBS Sympsoms and Performance of Office Work during Exposure to Air Polluted by Building Materials and Personal Computers

    DEFF Research Database (Denmark)

    Bako-Biro, Zsolt

    The present thesis deals with the impact of polluted air from building materials and personal computers on human perception, Sick Building Syndrome (SBS) symptoms and performance of office work. These effects have been studies in a series of experiments that are described in two different chapters...

  11. Evaluating the effect of increasing ceramic content on the mechanical properties, material microstructure and degradation of selective laser sintered polycaprolactone/β-tricalcium phosphate materials.

    Science.gov (United States)

    Doyle, Heather; Lohfeld, Stefan; McHugh, Peter

    2015-08-01

    Orthopaedic scaffold materials were fabricated from polycaprolactone (PCL) and composite PCL-β-tricalcium phosphate (PCL/β-TCP) powders using selective laser sintering (SLS). Incorporating β-TCP particles is desirable to promote osteogenesis. The effects of increasing β-TCP content on the material's mechanical properties and microstructure were evaluated. The wt% of β-TCP and PCL particle sizes were found to influence material microstructure and mechanical properties, with increasing ceramic content causing a small but significant increase in stiffness but significant reductions in strength. Degradation of materials was achieved using accelerated ageing methods. The influence of β-TCP content on degradation at 7 weeks was evaluated through changes in mechanical properties and microstructure, and the ceramic particles were found to reduce elastic modulus and increase strength. The results of this study highlight the influence of ceramic content on mechanical properties and degradation behaviour of PCL/β-TCP SLS materials, and indicate that these changes must be considered in the design of scaffolds for critical-sized defects.

  12. Future Resources for Eco-building Materials: I.Metallurgical Slag

    Institute of Scientific and Technical Information of China (English)

    XU Delong; LI Hui

    2009-01-01

    In order to make an effectivily recycle use of iron and steel slags that are main industrial wastes generated in Chinese metallurgical industry,the current technologies for reprocessing and recycling these wastes into eco-building materials were reviewed,such as preparing cement-steel slag blended cement with steel slag after metal recovery,using the fine powder of blast furnace slag (BFS)for manufacturing slag cement and high performance concrete.A further research on using these available resources more efficiently were discussed.

  13. Measurements of radioactivity and dose assessments in some building materials in Bitlis, Turkey.

    Science.gov (United States)

    Kayakökü, Halime; Karatepe, Şule; Doğru, Mahmut

    2016-09-01

    In this study, samples of perlite, pumice and Ahlat stones (Ignimbrite) extracted from mines in Bitlis and samples of other building materials produced in facilities in Bitlis were collected and analyzed. Activity concentrations of (226)Ra, (232)Th and (40)K in samples of building materials were measured using NaI detector (NaI(Tl)) with an efficiency of 24%. The radon measurements of building material samples were determined using CR-39 nuclear track detectors. (226)Ra, (232)Th and (40)K radioactivity concentrations ranged from (29.6±5.9 to 228.2±38.1Bq/kg), (10.8±5.4 to 95.5±26.1Bq/kg) and (249.3±124.7 to 2580.1±266.9Bq/kg), respectively. Radon concentration, radium equivalent activities, absorbed dose rate, excess lifetime cancer risk and the values of hazard indices were calculated for the measured samples to assess the radiation hazards arising from using those materials in the construction of dwellings. Radon concentration ranged between 89.2±12.0Bq/m(3) and 1141.0±225.0Bq/m(3). It was determined that Raeq values of samples conformed to world standards except for perlite and single samples of brick and Ahlat stone. Calculated values of absorbed dose rate ranged from 81.3±20.5 to 420.6±42.8nGy/h. ELCR values ranged from (1.8±0.3)×10(-3) to (9.0±1.0)×10(-3). All samples had ELCR values higher than the world average. The values of Hin and Hex varied from 0.35±0.11 to 1.78±0.18 and from 0.37±0.09 to 1.17±0.13, respectively. The results were compared with standard radioactivity values determined by international organizations and with similar studies. There would be a radiation risk for people living in buildings made of perlite, Ahlat-1 and Brick-3.

  14. Analysis of Phase Change Material in Glazing Systems in Future Zero-Energy-Buildings

    DEFF Research Database (Denmark)

    Winther, Frederik Vildbrad; Heiselberg, Per; Jensen, Rasmus Lund

    2016-01-01

    the thermal storage capacity of the glazed facade by using phase change material (PCM), in the glazing cavity, reduces the cooling demand. When wanting to use this technology under colder weather conditions, the pane can potentially reduce the heat loss of the pane thereby minimizing energy demand for heating.......When designing glazed constructions, this often results in thermally light constructions, with a low time constant. In order for these buildings to improve the redistribution of loads between night and day, solutions such as active slabs and exposed concrete cores are often used. However...

  15. The Feasibility of Wood and its Derivatives as a Bicycle Frame Building Material

    OpenAIRE

    BRENT TAYLOR, NICHOLAS

    2016-01-01

    [EN] ABSTRACT Nicholas Brent Taylor: The Feasibility of Wood and its Derivatives as a Bicycle Frame Building Material The bicycle is often considered as one of the most important inventions of all time. In addition, it is the most efficient form of human transport in the world. It is non pollutant, uses no fuel other than human power and its carbon footprint is neutralised in a short time. Today, faced with the threat of global warming brought about by fossil fuels, countries such as De...

  16. Dataset of Atmospheric Environment Publication in 2016, Characterization of organophosphorus flame retardants’ sorption on building materials and consumer products

    Data.gov (United States)

    U.S. Environmental Protection Agency — The data presented in this data file is a product of a journal publication. The dataset contains OPFR sorption concentrations on building materials and consumer...

  17. Development and application of new building materials%新型建筑材料的发展及应用

    Institute of Scientific and Technical Information of China (English)

    王兰

    2015-01-01

    我国新型建材工业是伴随着改革开放的不断深入而发展起来的.新型建材具有轻质、高强度、保温、节能等特点.本文从新型建筑材料的现状出发,重点探讨了新型建筑材料的发展及应用.%New building materials industry in China is accompanied by the deepening of the reform and opening up and developed. New building materials are lightweight,high strength,insulation,energy-saving features,In this paper,starting from the present situation of new building materials,Focus on the development and application of new building materials are discussed.

  18. Direct-bonded Magnesite-Chrome Bricks for Kilns and Furnaces of Building Materials Industry JC 497-92 ( 96 )

    Institute of Scientific and Technical Information of China (English)

    Yu Lingyan; Chai Junlan

    2008-01-01

    @@ 1 Contents and Applied Scope This standard specifies the classification, shapes and dimensions, technical requirements, test methods, inspection rules, marking, packing, transportation, storage and quality certificate of direct-bonded magne-site -chrome bricks for building materials industry.

  19. Our Buildings, Ourselves.

    Science.gov (United States)

    Roodman, David Malin; Lenssen, Nicholas

    1994-01-01

    Reviews in detail environmental impacts associated with buildings. Discusses building construction, internal environments, building life spans, building materials, protection from climate, and amenities. (LZ)

  20. Criteria for evaluation of building materials hazard based on their natural radioactivity in Russia and in the European Union countries

    Directory of Open Access Journals (Sweden)

    Buzina Darya

    2016-01-01

    Full Text Available We hereby have considered the natural radioactivity of building materials as a source of radiation for the human environment. We have considered the Russian and the European evaluation criteria for ensuring radiation safety of the population. We also present an experimental research of the content of natural radionuclides in building materials. We have calculated the effective specific activity and the activity concentration index based on the results presented. We have identified discrepancies between the Russian and the European standards.

  1. Material and Social Construction: A Framework for the Adaptation of Buildings

    Directory of Open Access Journals (Sweden)

    Jesse M. Keenan

    2014-12-01

    Full Text Available This article is a formulation of a framework for understanding the nature of change, particularly climate change, as it applies to the scale of a building. Through an exploration of various scientific and social scientific literutre, the article positions the concept of adaptation as the appropriate mode for understanding and managing change. Through the classification of a duality of material and social construction in the ontological composition of a building, various lines of thought relating to adaptive capacity and adaptive cycling within systems theory are appropriated within an integrated framework for adaptation. Specifically, it is theorized that as buildings as objects are developing greater capacities for intergrated operations and management through artificial intelligence, they will possess an ex ante capacity to autonomously adapt in dynamic relation to and with the ex post adaptation of owners and operators. It is argued that this top-down and bottom-up confluence of multi-scalar dynamic change is consistent with the prevailing theory of Panarchy applied in social-ecological systems theory. The article concludes with normative perspectives on the limitations of systems theory in architecture, future directions for research and an alternative positioning of professional practices.

  2. Building the Material Flow Networks of Aluminum in the 2007 U.S. Economy.

    Science.gov (United States)

    Chen, Wei-Qiang; Graedel, T E; Nuss, Philip; Ohno, Hajime

    2016-04-05

    Based on the combination of the U.S. economic input-output table and the stocks and flows framework for characterizing anthropogenic metal cycles, this study presents a methodology for building material flow networks of bulk metals in the U.S. economy and applies it to aluminum. The results, which we term the Input-Output Material Flow Networks (IO-MFNs), achieve a complete picture of aluminum flow in the entire U.S. economy and for any chosen industrial sector (illustrated for the Automobile Manufacturing sector). The results are compared with information from our former study on U.S. aluminum stocks and flows to demonstrate the robustness and value of this new methodology. We find that the IO-MFN approach has the following advantages: (1) it helps to uncover the network of material flows in the manufacturing stage in the life cycle of metals; (2) it provides a method that may be less time-consuming but more complete and accurate in estimating new scrap generation, process loss, domestic final demand, and trade of final products of metals, than existing material flow analysis approaches; and, most importantly, (3) it enables the analysis of the material flows of metals in the U.S. economy from a network perspective, rather than merely that of a life cycle chain.

  3. Thermal properties of a new ecological building material / Granular cork embedded in white cement

    Directory of Open Access Journals (Sweden)

    Cherki Abou-bakr

    2014-04-01

    Full Text Available Cork, natural and renewable product, has thermal and acoustic properties very interesting because of its microstructure and porosity representing a significant portion of its apparent volume; it’s coming from Moroccan Maamora’s forest. This work is a contribution to understand the thermal behaviour of the composite material based on granular cork embedded in white cement. An experimental investigation of its thermal properties was mainly performed using the asymmetrical device of transient Hot Plate method. The effect of granular cork size on the thermal properties of the mixture was studied. The experimental study of this sustainable material aims to characterize its thermal properties and then compare them with those of white cement without cork for motivate the proposal that this composite material will be used as walls insulator. A comparison of the energy performances of the composite material and white cement was made; it allows deducing a very interesting energy gain. The findings of the experiments indicate that the composite is better than white cement in term of thermal insulation, energy storage capacity and lightness. So, it can be used to realize the internal walls insulation. Its utilization should contribute to the improvement of the energy efficiency in building especially that this is a mixture based on a sustainable and renewable material.

  4. Nucleic acids and smart materials: advanced building blocks for logic systems.

    Science.gov (United States)

    Pu, Fang; Ren, Jinsong; Qu, Xiaogang

    2014-09-03

    Logic gates can convert input signals into a defined output signal, which is the fundamental basis of computing. Inspired by molecular switching from one state to another under an external stimulus, molecular logic gates are explored extensively and recognized as an alternative to traditional silicon-based computing. Among various building blocks of molecular logic gates, nucleic acid attracts special attention owing to its specific recognition abilities and structural features. Functional materials with unique physical and chemical properties offer significant advantages and are used in many fields. The integration of nucleic acids and functional materials is expected to bring about several new phenomena. In this Progress Report, recent progress in the construction of logic gates by combining the properties of a range of smart materials with nucleic acids is introduced. According to the structural characteristics and composition, functional materials are categorized into three classes: polymers, noble-metal nanomaterials, and inorganic nanomaterials. Furthermore, the unsolved problems and future challenges in the construction of logic gates are discussed. It is hoped that broader interests in introducing new smart materials into the field are inspired and tangible applications for these constructs are found.

  5. Measurement of natural radioactivity in building materials of Namakkal, Tamil Nadu, India using gamma-ray spectrometry.

    Science.gov (United States)

    Ravisankar, R; Vanasundari, K; Chandrasekaran, A; Rajalakshmi, A; Suganya, M; Vijayagopal, P; Meenakshisundaram, V

    2012-04-01

    The natural level of radioactivity in building materials is one of the major causes of external exposure to γ-rays. The primordial radionuclides in building materials are one of the sources of radiation hazard in dwellings made of these materials. By the determination of the radioactivity level in building materials, the indoor radiological hazard to human health can be assessed. This is an important precautionary measure whenever the dose rate is found to be above the recommended limits. The aim of this work was to measure the specific activity concentration of (226)Ra, (232)Th and (40)K in commonly used building materials from Namakkal, Tamil Nadu, India, using gamma-ray spectrometer. The radiation hazard due to the total natural radioactivity in the studied building materials was estimated by different approaches. The concentrations of the natural radionuclides and the radium equivalent activity in studied samples were compared with the corresponding results of different countries. From the analysis, it is found that these materials may be safely used as construction materials and do not pose significant radiation hazards.

  6. Identification and Assessment of Material Models for Age-Related Degradation of Structures and Passive Components in Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Nie,J.; Braverman, J.; Hofmayer, C.; Kim, M. K.; Choi, I-K.

    2009-04-27

    describes the research effort performed by BNL for the Year 2 scope of work. This research focused on methods that could be used to represent the long-term behavior of materials used at NPPs. To achieve this BNL reviewed time-dependent models which can approximate the degradation effects of the key materials used in the construction of structures and passive components determined to be of interest in the Year 1 effort. The intent was to review the degradation models that would cover the most common time-dependent changes in material properties for concrete and steel components.

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

    Directory of Open Access Journals (Sweden)

    Yoo Yong Ho

    2013-11-01

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

  8. Integrating Si nanoscale building blocks into micro-sized materials to enable practical applications in lithium-ion batteries.

    Science.gov (United States)

    Yi, Ran; Gordin, Mikhail L; Wang, Donghai

    2016-01-28

    This article highlights recent advances in micro-sized silicon anode materials composed of silicon nanoscale building blocks for lithium-ion batteries. These materials show great potential in practical applications since they combine good cycling stability, high rate performance, and high volumetric capacity. Different preparation methods are introduced and the features and performance of the resulting materials are discussed. Key take-away points are interspersed through the discussion, including comments on the roles of the nanoscale building blocks. Finally, we discuss current challenges and provide an outlook for future development of micro-sized silicon-based anode materials.

  9. Gamma Radiation Measurements and Dose Rates in Commonly Used Building Materials in Cyprus

    CERN Document Server

    Michael, F; Parpottas, Y

    2010-01-01

    A first comprehensive study is presented on radioactivity concentrations and dose rates in 87 commonly used materials, manufactured or imported in Cyprus, for building purposes. The natural radioactivity of K-40, Th-232, U-238 and Ra-226 is determined using high-resolution gamma ray spectroscopy. The respective dose rates and the associated radiological effect indices are also calculated. A comparison of the measured specific activity values with the corresponding world average values shows that most of them are below the world average activity values. The annual indoor effective dose rates received by an individual from three measured imported granites and four measured imported ceramics are found to be higher than the world upper limit value of 1 mSv y-1. Hence, these materials should have a restricted use according to their corresponding calculated activity concentration index values and the related EC 1999 guidelines.

  10. Diffuse Reflectance Infrared Fourier Transform Spectroscopy for the Determination of Asbestos Species in Bulk Building Materials

    Directory of Open Access Journals (Sweden)

    Grazia Accardo

    2014-01-01

    Full Text Available Diffuse reflectance infrared Fourier transform (DRIFT spectroscopy is a well-known technique for thin film characterization. Since all asbestos species exhibit intense adsorptions peaks in the 4000–400 cm−1 region of the infrared spectrum, a quantitative analysis of asbestos in bulk samples by DRIFT is possible. In this work, different quantitative analytical procedures have been used to quantify chrysotile content in bulk materials produced by building requalification: partial least squares (PLS chemometrics, the Linear Calibration Curve Method (LCM and the Method of Additions (MoA. Each method has its own pros and cons, but all give affordable results for material characterization: the amount of asbestos (around 10%, weight by weight can be determined with precision and accuracy (errors less than 0.1.

  11. Multifunctional hybrids by combining ordered mesoporous materials and macromolecular building blocks.

    Science.gov (United States)

    Soler-Illia, Galo J A A; Azzaroni, Omar

    2011-02-01

    This critical review presents and discusses the recent advances in complex hybrid materials that result from the combination of polymers and mesoporous matrices. Ordered mesoporous materials derived from supramolecular templating present high surface area and tailored pore sizes; pore surfaces can be further modified by organic, organometallic or even biologically active functional groups. This permits the creation of hybrid systems with distinct physical properties or chemical functions located in the framework walls, the pore surface, and the pore interior. Bringing polymeric building blocks into the game opens a new dimension: the possibility to create phase separated regions (functional domains) within the pores that can behave as "reactive pockets" of nanoscale size, with highly controlled chemistry and interactions within restricted volumes. The possibilities of combining "hard" and "soft" building blocks to yield these novel nanocomposite materials with tuneable functional domains ordered in space are potentially infinite. New properties are bound to arise from the synergy of both kinds of components, and their spatial location. The main object of this review is to report on new approaches towards functional polymer-inorganic mesostructured hybrids, as well as to discuss the present challenges in this flourishing research field. Indeed, the powerful concepts resulting from the synergy of sol-gel processing, supramolecular templating and polymer chemistry open new opportunities in the design of advanced functional materials: the tailored production of complex matter displaying spatially-addressed chemistry based on the control of chemical topology. Breakthrough applications are expected in the fields of sustainable energy, environment sensing and remediation, biomaterials, pharmaceutical industry and catalysis, among others (221 references).

  12. Materials development and field demonstration of high-recycled-content concrete for energy-efficient building construction

    Energy Technology Data Exchange (ETDEWEB)

    Ostowari, Ken; Nosson, Ali

    2000-09-30

    The project developed high-recycled-content concrete material with balanced structural and thermal attributes for use in energy-efficient building construction. Recycled plastics, tire, wool, steel and concrete were used as replacement for coarse aggregates in concrete and masonry production. With recycled materials the specific heat and thermal conductivity of concrete could be tailored to enhance the energy-efficiency of concrete buildings. A comprehensive field project was implemented which confirmed the benefits of high-recycled-content concrete for energy-efficient building construction.

  13. Characterization of Particle Size Distributions of Powdery Building Material Aerosol Generated by Fluidization and Gravitation

    Directory of Open Access Journals (Sweden)

    Tadas Prasauskas

    2012-10-01

    Full Text Available This study aims to identify particle size distributions (PSD of aerosol of powdery building materials commonly used in construction work (cement, chalk, clay, wood sawdust, wood grinding dust, gypsum, hydrated lime, masonry grout, quartz sand, sand and structural lime by two aerosolization methods: fluidization and gravitation. Fluidization and gravitation methods represent industrial activities such as pneumotransportation and unloading. Both particle resuspension mechanisms have been modelled in laboratory conditions. The particle size distributions of resuspended particulate matter from powdery building materials were rather similar identified by both fluidization and gravitation methods, with an exception of wood sawdust and sand. The PM10 fraction ranged between 30% and 87%, PM2.5 from 7% to 28% and PM1.0 from 3% to 7% of the total mass of particulate matter. The highest PM10/PMtotal ratio was calculated for masonry grout - 0.87, and the lowest ratio for quartz sand - 0.30. The highest ratio of PM2.5/PMtotal was calculated for sand - 0.23, the lowest for quartz sand - 0.07. Substantial quantities of PM2.5 were found to be emitted implying a potential threat to human health.DOI: http://dx.doi.org/10.5755/j01.erem.61.3.1519

  14. Impact of Water Chemistry, Pipe Material and Stagnation on the Building Plumbing Microbiome.

    Directory of Open Access Journals (Sweden)

    Pan Ji

    Full Text Available A unique microbiome establishes in the portion of the potable water distribution system within homes and other buildings (i.e., building plumbing. To examine its composition and the factors that shape it, standardized cold water plumbing rigs were deployed at the treatment plant and in the distribution system of five water utilities across the U.S. Three pipe materials (copper with lead solder, CPVC with brass fittings or copper/lead combined pipe were compared, with 8 hour flush cycles of 10 minutes to simulate typical daily use patterns. High throughput Illumina sequencing of 16S rRNA gene amplicons was employed to profile and compare the resident bulk water bacteria and archaea. The utility, location of the pipe rig, pipe material and stagnation all had a significant influence on the plumbing microbiome composition, but the utility source water and treatment practices were dominant factors. Examination of 21 water chemistry parameters suggested that the total chlorine concentration, pH, P, SO42- and Mg were associated with the most of the variation in bulk water microbiome composition. Disinfectant type exerted a notably low-magnitude impact on microbiome composition. At two utilities using the same source water, slight differences in treatment approaches were associated with differences in rare taxa in samples. For genera containing opportunistic pathogens, Utility C samples (highest pH of 9-10 had the highest frequency of detection for Legionella spp. and lowest relative abundance of Mycobacterium spp. Data were examined across utilities to identify a true universal core, special core, and peripheral organisms to deepen insight into the physical and chemical factors that shape the building plumbing microbiome.

  15. Polyester-based (bio)degradable polymers as environmentally friendly materials for sustainable development.

    Science.gov (United States)

    Rydz, Joanna; Sikorska, Wanda; Kyulavska, Mariya; Christova, Darinka

    2014-12-29

    This review focuses on the polyesters such as polylactide and polyhydroxyalkonoates, as well as polyamides produced from renewable resources, which are currently among the most promising (bio)degradable polymers. Synthetic pathways, favourable properties and utilisation (most important applications) of these attractive polymer families are outlined. Environmental impact and in particular (bio)degradation of aliphatic polyesters, polyamides and related copolymer structures are described in view of the potential applications in various fields.

  16. New Porous Material Made from Industrial and Municipal Waste for Building Application

    Directory of Open Access Journals (Sweden)

    Diana BAJARE

    2014-09-01

    Full Text Available The aim of this study was to find a new method for usage of the hazardous waste coming from recycling industry. Two hazardous wastes – aluminium recycling final dross or non-metallic product (NMP and lead – silica glass (LSG were investigated. It is generally considered that NMP is a process waste and subject to disposal after residual metal has been recovered from primary dross. NMP is impurities which are removed from the molten metal in dross recycling process and it could be defined as a hazardous waste product in aluminium recycling industry. LSG comes from fluorescence lamp recycling plant and could be classified as hazardous waste due to high amount of lead in the composition and re-melting problems. The new alkali activated material, which can be defined as porous building material, was created. Composition of this material consisted of aluminium recycling waste, recycled fluorescent lamp LSG, sintered kaolin clay as well as commercially available alkali flakes (NaOH and liquid glass (Na2SiO3 + nH2O. Physical and mechanical properties of the obtained material were tested. Density of the obtained material was from (460 – 550 kg/m3 and the total porosity was from 82 % – 83 %. The compressive strength of the material was in range from 1.1 MPa to 2.3 MPa. The thermal conductivity was determined. The pore microstructure was investigated and the mineralogical composition of porous material was determined. DOI: http://dx.doi.org/10.5755/j01.ms.20.3.4330

  17. Nonlinear Effect of Moisture Content on Effective Thermal Conductivity of Building Materials with Different Pore Size Distributions

    Science.gov (United States)

    Liu, Yanfeng; Ma, Chao; Wang, Dengjia; Wang, Yingying; Liu, Jiaping

    2016-06-01

    Understanding the quantitative relationship between the effective thermal conductivity and the moisture content of a material is required to accurately calculate the envelope heat and mass transfer and, subsequently, the building energy consumption. We experimentally analyzed the pore size distributions and porosities of common building materials and the influence of the moisture content on the effective thermal conductivity of building materials. We determined the quantitative relationship between the effective thermal conductivity and moisture content of building materials. The results showed that a larger porosity led to a more significant effect of the moisture content on the effective thermal conductivity. When the volumetric moisture content reached 10 %, the thermal conductivities of foam concrete and aerated concrete increased by approximately 200 % and 100 %, respectively. The effective thermal conductivity increased rapidly in the low moisture content range and increased slowly in the high moisture content range. The effective thermal conductivity is related to the moisture content of the materials through an approximate power function. As the moisture content in the walls of a new building stabilizes, the effective thermal conductivity of normal concrete varies only slightly, whereas that of aerated concrete varies more significantly. The effective thermal conductivity of the material is proportional to the relative humidity of the environment. This trend is most noticeable when the wall material is aerated concrete.

  18. Brief Discussion on China's Green Building Materials%浅谈我国绿色建筑材料

    Institute of Scientific and Technical Information of China (English)

    齐锋

    2014-01-01

    Starting from the deifnition of"green building material"and combining green materials in China, this paper elaborates what materials are "green materials"with whole lifecycle evaluation of building material as entry point, and finally it combines status quo of China's green building materials to proposes suggestion on development of China's green building. It hopes this paper would be beneficial for development of China's green building material market.%文章从“绿色建材”的定义出发,结合国内绿色建筑,以建筑材料的全寿命周期评价为切入点,详细阐述什么样的建筑材料是“绿色建材”,最后结合国内绿色建材的现状,对我国绿色建材的发展提出一点小小的建议,希望能对我国绿色建材市场的发展有所裨益。

  19. The Monastery of Uclés (Cuenca, Spain: characterization and deterioration of building materials

    Directory of Open Access Journals (Sweden)

    Álvarez De Buergo, M.

    2004-09-01

    Full Text Available Building materials from the Monastery of Uclés façades, in Cuenca (16th-18 th centuries, have been characterised, as well as identified their deterioration forms. Characterization consisted of the determination o mineralogical and petrographical properties of building materials; petrophysical and petrochemical characterization of building stones were also carried out. Stony materials are basically of two types, dolostones and limestones. Ashlars joint mortars are of three classes, chronologically from the oldest to the newest: lime mortars with siliceous and dolomitic aggregates, gypsum/lime mortars with dolomitic aggregates, and gypsum/lime mortars with siliceous aggregates. The façades have been protected with artificial patinas of three kinds: lime, lime/gypsum and gypsum patinas, chronologically from the oldest to the newest, with a variable thickness from 500 µm. The dolomitic fades are better conserved than the calcareous ones, and the covering artificial patinas presence have preserved the materials on which they were applied.

    Se han caracterizado ¡os materiales de construcción de las fachadas del Monasterio de Uclés en Cuenca (s. XVI-XVIII así como sus formas de deterioro. La caracterización consistió en la determinación de sus características mineralógicas, petrográficas y petroquímicas, asi como la caracterización petrofisica de los materiales pétreos. Las piedras de construcción son, fundamentalmente, de dos tipos, dolomías y calizas. Los morteros de rejuntado de los sillares son de tres tipos, en orden cronológico, de más antiguos a más modernos: morteros de cal con áridos silíceos y dolomíticos, morteros de cal/yeso con áridos dolomílicos, y morteros de yeso/cal con áridos silíceos. Las fachadas han estado protegidas por pátinas artificiales de tres tipos: de cal, de cal/yeso y de yeso; en orden cronológico, de más antiguas a más modernas, con espesores variables desde < 100µm

  20. Study and inquiry on green building materials%绿色建筑材料的研究与探讨

    Institute of Scientific and Technical Information of China (English)

    吴枫; 邵兵; 周婷婷; 杨杰

    2015-01-01

    The paper introduces the definition of green building materials,illustrates basic standards needing following in estimating green build-ing materials,analyzes green building material application status including green wall materials,green glass,green ecological cement and so on, and finally points out that:the development trend of domestic green building materials has significant meaning for building sustainable and re-sources-saving society.%简要介绍了绿色建筑材料的含义,说明了评估绿色建筑材料应遵循的基本标准,并对绿色墙体材料、绿色玻璃、绿色生态水泥等建筑材料的应用现状进行了分析,指出了我国绿色建筑材料的发展趋势,对构建可持续发展的资源节约型社会有重要意义。

  1. Electrochemical synthesis of FeS{sub 2} thin film: An effective material for peroxide sensing and terephthalic acid degradation

    Energy Technology Data Exchange (ETDEWEB)

    Jana, Sumanta [Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Howrah, 711103 WB (India); Mondal, Palash; Tripathi, Subhankar [Department of Chemistry, Vivekananda Mahavidyalaya, Burdwan, 713103 WB (India); Mondal, Anup [Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Howrah, 711103 WB (India); Chakraborty, Biswajit, E-mail: biswajitmailbag@gmail.com [Department of Chemistry, Vivekananda Mahavidyalaya, Burdwan, 713103 WB (India)

    2015-10-15

    Electrochemically FeS{sub 2} thin films have been synthesized on ITO substrates at room temperature (25 °C). UV–Vis, X-ray diffraction (XRD) and field emission scanning electron microscope (FESEM) were used for the characterization of nanostructure FeS{sub 2} thin films. Two probe I–V measurements convey that the material is p type and a p-n junction (diode) was found to be developed between FeS{sub 2} and ITO layer. Cyclic voltametry study shows that FeS{sub 2}/ITO electrode facilitates the reduction of hydrogen peroxide and exhibits excellent electro-catalytic activity towards its sensing. Photocatalytic study reveals that the synthesized thin films are also efficient to degrade terephthalic acid (TA). - Graphical abstract: Electrochemically FeS{sub 2} thin films have been synthesized on ITO substrate. The synthesized material is effective for the reduction of H{sub 2}O{sub 2} and the sensitivity of the material is strongly dependent on pH and temperature. Photocatalytic study reveals that the material is quite effective towards decomposition of terephthalic acid. These results indicate that the material can play a dual role as pollutant cleanup for environmental interest. - Highlights: • Electrochemically FeS{sub 2} thin films are synthesized. • The material is effective to sense the H{sub 2}O{sub 2} and degrade terephthalic acid. • It plays a dual role as pollutant cleanup for environmental interest.

  2. PRESENT-DAY AND FUTURE APPLICATIONS OF NANOTECHNOLOGIES IN THE PRODUCTION OF BUILDING MATERIALS

    Directory of Open Access Journals (Sweden)

    Shuyskiy Anatoliy Ivanovich

    2012-12-01

    Full Text Available The authors have made an overview of the status of production of cement concrete using nanotechnologies. The authors also provide their analysis of domestic and foreign researches into the application of nanotechnologies in the field of building materials. The authors have picked out positive examples of introduction of nano-scale particles into the concrete mix. The process needs continuous monitoring for the composition and the mixing time to be adjustable. The findings have been solely made by local developers of nano-materials and technologies. The authors propose their method of cement consumption reduction through the introduction of nanoparticles and simultaneous grinding of cement. The authors provide a new procedure of treatment of materials that contemplates enhanced mixing processes accompanied by simultaneous grinding of materials and their exposure to the electromagnetic treatment. The experiments completed by the team of authors have proven the efficiency of a combination of two nanotechnologies within one process, including the treatment of wet cement at the final grinding stage of processing to ensure specific cement properties for a specific surface area of 8,000 cm2/g, and the introduction of nano-scale particles into the process of manufacturing of cement compositions. The use of carbon nanotubes in the process of manufacturing of cement concrete can improve its physical and mechanical properties and reduce the cement consumption rate while maintaining the design strength of concrete.

  3. Bacillus spores as building blocks for stimuli-responsive materials and nanogenerators

    Science.gov (United States)

    Chen, Xi; Mahadevan, L.; Driks, Adam; Sahin, Ozgur

    2014-02-01

    Materials that respond mechanically to external chemical stimuli have applications in biomedical devices, adaptive architectural systems, robotics and energy harvesting. Inspired by biological systems, stimuli-responsive materials have been created that can oscillate, transport fluid, provide homeostasis and undergo complex changes in shape. However, the effectiveness of synthetic stimuli-responsive materials in generating work is limited when compared with mechanical actuators. Here, we show that the mechanical response of Bacillus spores to water gradients exhibits an energy density of more than 10 MJ m-3, which is two orders of magnitude higher than synthetic water-responsive materials. We also identified mutations that can approximately double the energy density of the spores and found that they can self-assemble into dense, submicrometre-thick monolayers on substrates such as silicon microcantilevers and elastomer sheets, creating bio-hybrid hygromorph actuators. To illustrate the potential applications of the spores, we used them to build an energy-harvesting device that can remotely generate electrical power from an evaporating body of water.

  4. High-power diode laser marking and engraving of building materials

    Science.gov (United States)

    Li, Lin; Lawrence, Jonathan; Spencer, Julian T.

    1997-08-01

    A Diomed 60W-cw high power diode laser (HPDL) has been used for the marking and engraving of various building materials, including; marble, granite, clay tiles, ceramic tiles, roof tiles, ordinary Portland cement (OPC) and clay bricks. Morphological and microstructural characteristics have been investigated. The basic mechanism of marking/engraving and the characteristics of the beam absorption are discussed. The effects of material texture, color and laser processing parameters are reported. The work shows that engraving depths of over 2 mm (0.75 mm for a single pass) can be achieved on marble substrates by thermal disintegration of CaCO3 into loose CaO powder and CO2 gas. Uniform amorphous glazed lines (1 - 3 mm line width) of a color different from the untreated materials can be generated on clay tiles, ceramic tiles, roof tiles, clay bricks and OPC by solidification phase formation after laser melting of these materials. Effects of atmospheric conditions, for instance using O2 and Ar gas shrouds, have been examined, with different colored marks being observed when different shroud gases are used. To demonstrate the practical worth of the process a UMIST crest has been marked on a ceramic tile using the system. Laser beam reflectivity is found to depend not only on material composition but also its color. Reflectivity has been found to range between 12% to 18% for the various construction materials used in the experiment, except for marble (grey) which showed over 27% reflectivity. Since the HPDL is a portable device, on-site application of these processing techniques can be realized, which would be either impossible or difficult when using other types of lasers.

  5. Titania-alumina aerogel materials for degradation of rhodamine B dye: Impact of particle size of titania

    Science.gov (United States)

    Shrestha, Sunav

    Disposal of pollutants, mainly organic dyes from textile industries are the primary sources of water pollution in developing countries, and often leading to scarcity of clean water. These dyes can undergo further oxidation and form several toxic compounds, which possess threat to the water ecosystem. It is therefore necessary to remove these organics from effluents for a clean environment. Among the various methods, Advanced Oxidation Processes (AOPs) called heterogeneous photocatalysis is considered as an effective method for the removal of organics from water sources. In this regard, a set of titania-alumina (TiO2-Al2O3) mixed oxide materials were prepared by supercritical drying method and investigated towards the degradation of a model pollutant, rhodamine B (RhB). The physico-chemical properties of the synthesized materials were studied in detail using several techniques that include powder X-ray diffraction, nitrogen physisorption, diffuse reflectance spectroscopy, and X-ray photoelectron spectroscopy (XPS). The Electrospray ionization-Mass spectroscopic (ESI-MS) studies were also carried out to confirm the degradation of the RhB by identifying its intermediate products. The results indicate that the particle size of the photoactive species, titania, was the key factor for effective photocatalytic degradation of the RhB dye over the titania-alumina mixed oxide materials.

  6. CSCEC and Chinalco Joined Hands to Invest 5 Billion Yuan for Making Deployment in Building New Materials

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

    CSCEC-Chinalco New Material Co.,Ltd,a company jointly invested by China State Construction Engineering Corporation(CSCEC)and Chinalco,was inaugurated in Chengdu,Sichuan,on December 15,CSCECChinalco will invest nearly 5 billion yuan capital in the next five years to makedeployment in the building new materials

  7. Degradable magnesium-based implant materials with anti-inflammatory activity.

    Science.gov (United States)

    Peng, Qiuming; Li, Kun; Han, Zengsheng; Wang, Erde; Xu, Zhigang; Liu, Riping; Tian, Yongjun

    2013-07-01

    The objective of this study was to prepare a new biodegradable Mg-based biomaterial, which provides good mechanical integrity in combination with anti-inflammatory function during the degradation process. The silver element was used, because it improved the mechanical properties as an effective grain refiner and it is also treated as a potential anti-inflammatory core. The new degradable Mg-Zn-Ag biomaterial was prepared by zone solidification technology and extrusion. The mechanical properties were mostly enhanced by fine grain strengthening. In addition, the alloys exhibited good cytocompatibility. The anti-inflammatory function of degradation products was identified by both interleukin-1α and nitric oxide modes. The anti-inflammatory impact was significantly associated with the concentration of silver ion. It was demonstrated that Mg-Zn-Ag system was a potential metallic stent with anti-inflammatory function, which can reduce the long-term dependence of anti-inflammatory drug after coronary stent implantation.

  8. Determination of the mechanism and extent of surface degradation in Ni-based cathode materials after repeated electrochemical cycling

    Directory of Open Access Journals (Sweden)

    Sooyeon Hwang

    2016-09-01

    Full Text Available We take advantage of scanning transmission electron microscopy and electron energy loss spectroscopy to investigate the changes in near-surface electronic structure and quantify the degree of local degradation of Ni-based cathode materials with the layered structure (LiNi0.8Mn0.1Co0.1O2 and LiNi0.4Mn0.3Co0.3O2 after 20 cycles of delithiation and lithiation. Reduction of transition metals occurs in the near-surface region of cathode materials: Mn is the major element to be reduced in the case of relatively Mn-rich composition, while reduction of Ni ions is dominant in Ni-rich materials. The valences of Ni and Mn ions are complementary, i.e., when one is reduced, the other is oxidized in order to maintain charge neutrality. The depth of degradation zone is found to be much deeper in Ni-rich materials. This comparative analysis provides important insights needed for the devising of new cathode materials with high capacity as well as long lifetime.

  9. Assessment of natural radioactivity and associated radiation hazards in some building materials used in Kilpenathur, Tiruvannamalai dist, Tamilnadu, India

    Energy Technology Data Exchange (ETDEWEB)

    Raghu, Y. [Department of Physics, AarupadaiVeedu Institute of Technology, Paiyanoor, Chennai 603 104, Tamilnadu (India); Harikrishnan, N.; Ravisankar, R., E-mail: ravisankarphysics@gmail.com [Department of Physics, Government Arts College, Tiruvannamalai 606603, Tamilnadu (India); Chandrasekaran, A. [Departement of physics, SSN College of Engineering, Chennai- 603110, Tamilnadu India (India)

    2015-08-28

    The present study aimed to measure the radioactivity concentration of naturally occuring radionuclides in the locally used building materials from Kilpenthaur, Tiruvannmalai Dist, Tamilnadu, India. This study will also evaluate the radiation hazard arising due to the use of these materials in the construction of dwellings. The concentrations of natural radionuclides {sup 226}Ra, {sup 232}Th and {sup 40}K in five types of building materials have been measured by gamma spectrometry using NaI (Tl) 3” x 3”detector. The estimated radium equivalent activities (Ra{sub eq}), indoor absorbed gamma dose rate (D{sub R}), annual effective dose rate (H{sub R}) and the external hazard indexes(H{sub ex}) were lower than the recommended safe limit and are comparable with results from similar studies conducted in other countries. Therefore, the use of these building material samples under investigation in the construction of dwellings is considered to be safe for inhabitants.

  10. Measurement of color in different construction materials. The restoration in sandstone buildings

    Directory of Open Access Journals (Sweden)

    García Pascua, N.

    1999-03-01

    Full Text Available The use of construction materials and their subsequent repair purposes include a search of knowledge and preservation of their original appearance. For this reason, the main aim of this study is to determine a color range which does not change with the possible actions on a building, both when restoration works which imply the use and repair of "ancient" materials are carried out, and when construction is carried out with new materials. It is necessary to obtain the quantification of this property in order to check its variation over the passage of time. Each construction material must be taken into account as an isolated problem, since the color is different in each case.

    El empleo de materiales de construcción y la aplicación sobre ellos de productos de reparación requiere un detallado estudio sobre su forma de actuación y la importancia de la conservación del aspecto original de los mismos. Por este motivo, el objetivo principal de este estudio es el determinar un intervalo de color que se conserve a pesar de todas las posibles intervenciones que se acometan en el edificio, tanto cuando se realizan trabajos de restauración, que implican el uso y reparación de materiales "viejos", o bien cuando se llevan a cabo trabajos de construcción con materiales nuevos. Es necesario cuantificar dicha propiedad para poder controlar el paso del tiempo. Cada material de construcción debe ser considerado como un problema aislado, ya que el color es distinto en cada caso.

  11. First characterisation of natural radioactivity in building materials manufactured in Albania.

    Science.gov (United States)

    Xhixha, G; Ahmeti, A; Bezzon, G P; Bitri, M; Broggini, C; Buso, G P; Caciolli, A; Callegari, I; Cfarku, F; Colonna, T; Fiorentini, G; Guastaldi, E; Mantovani, F; Massa, G; Menegazzo, R; Mou, L; Prifti, D; Rossi Alvarez, C; Sadiraj Kuqi, Dh; Shyti, M; Tushe, L; Xhixha Kaçeli, M; Zyfi, A

    2013-07-01

    This study focuses on the radiological characterisation of building materials manufactured in Albania by using a high-resolution gamma-ray spectrometer. The average activity concentrations of (40)K, (226)Ra and (232)Th were, respectively, 644.1±64.2, 33.4 ± 6.4 and 42.2 ± 7.6 Bq kg(-1) in the clay brick samples and 179.7 ± 48.9, 55.0 ± 5.8 and 17.0 ± 3.3 Bq kg(-1) in the cement samples. The calculated activity concentration index (ACI), varied from 0.48±0.02 to 0.63±0.04 in the clay brick samples and from 0.29±0.03 to 0.37±0.02 in the cement samples. Based on the ACI, all of the clay brick and cement samples were categorised as A1 materials. The authors can exclude (at 3σ level) any restriction of their use as bulk materials.

  12. Integration of Agricultural Waste in Local Building Materials for their Exploitation: Application with Rice Straw

    Directory of Open Access Journals (Sweden)

    D. Sow

    2014-04-01

    Full Text Available Through experiments, we have determined the mechanical and thermal properties of samples. This allowed us to determine the most optimal formulations. Therefore, we have prepared samples constituted by two basic materials, clay and laterite, mixed with rice straw. Thus, agriculture is among the economic sectors that produce more waste. The latter are mainly the straw of the three most-produced cereals in the world: wheat, corn and rice. Concerning rice straw, its high content of cellulose makes it difficult to digest. So, few animals are able to use it as food. Most of the straws are lost, buried, burned or used as litter. Moreover, clay and laterite formations represent the most abundant materials resources in Africa. So, this study has allowed us to show that the integration of rice straw in lateritic and clay soils for its use as building materials will allow, in addition to its recycling, to greatly reduce the social habitat cost and to improve the thermal comfort.

  13. Preparation and Characterization of Microencapsulated Phase Change Materials for Use in Building Applications

    Directory of Open Access Journals (Sweden)

    Jessica Giro-Paloma

    2015-12-01

    Full Text Available A method for preparing and characterizing microencapsulated phase change materials (MPCM was developed. A comparison with a commercial MPCM is also presented. Both MPCM contained paraffin wax as PCM with acrylic shell. The melting temperature of the PCM was around 21 °C, suitable for building applications. The M-2 (our laboratory made sample and Micronal® DS 5008 X (BASF samples were characterized using SEM, DSC, nano-indentation technique, and Gas Chromatography/Mass spectrometry (GC-MS. Both samples presented a 6 μm average size and a spherical shape. Thermal energy storage (TES capacities were 111.73 J·g−1 and 99.3 J·g−1 for M-2 and Micronal® DS 5008 X, respectively. Mechanical characterization of the samples was performed by nano-indentation technique in order to determine the elastic modulus (E, load at maximum displacement (Pm, and displacement at maximum load (hm, concluding that M-2 presented slightly better mechanical properties. Finally, an important parameter for considering use in buildings is the release of volatile organic compounds (VOC’s. This characteristic was studied at 65 °C by CG-MS. Both samples showed VOC’s emission after 10 min of heating, however peaks intensity of VOC’s generated from M-2 microcapsules showed a lower concentration than Micronal® DS 5008 X.

  14. Analytical model of threshold voltage degradation due to localized charges in gate material engineered Schottky barrier cylindrical GAA MOSFETs

    Science.gov (United States)

    Kumar, Manoj; Haldar, Subhasis; Gupta, Mridula; Gupta, R. S.

    2016-10-01

    The threshold voltage degradation due to the hot carrier induced localized charges (LC) is a major reliability concern for nanoscale Schottky barrier (SB) cylindrical gate all around (GAA) metal-oxide-semiconductor field-effect transistors (MOSFETs). The degradation physics of gate material engineered (GME)-SB-GAA MOSFETs due to LC is still unexplored. An explicit threshold voltage degradation model for GME-SB-GAA-MOSFETs with the incorporation of localized charges (N it) is developed. To accurately model the threshold voltage the minimum channel carrier density has been taken into account. The model renders how +/- LC affects the device subthreshold performance. One-dimensional (1D) Poisson’s and 2D Laplace equations have been solved for two different regions (fresh and damaged) with two different gate metal work-functions. LCs are considered at the drain side with low gate metal work-function as N it is more vulnerable towards the drain. For the reduction of carrier mobility degradation, a lightly doped channel has been considered. The proposed model also includes the effect of barrier height lowering at the metal-semiconductor interface. The developed model results have been verified using numerical simulation data obtained by the ATLAS-3D device simulator and excellent agreement is observed between analytical and simulation results.

  15. Assessment of alpha activity of building materials commonly used in West Bengal, India.

    Science.gov (United States)

    Ghosh, Dipak; Deb, Argha; Bera, Sukumar; Sengupta, Rosalima; Patra, Kanchan Kumar

    2008-02-01

    This paper, reports for the first time, an extensive study of alpha activity of all widely used building materials (plaster of Paris, stone chips, marble, white cement, mosaic stone, limestone, sand, granite, cement brick, asbestos, red brick, cement tile, ceramic tile and ceramics) in West Bengal, India. The alpha activities have been measured using Solid State Nuclear Track Detector (SSNTD), a very sensitive detector for alpha particles. The samples were collected from local markets of Kolkata. The measured average alpha activities ranged from 22.7+/-2.5 to 590.6+/-16.8Bqkg(-1). The alpha activity of ceramic tiles was highest and provides additional data to estimate the effect of environmental radiation exposure on human health.

  16. Dynamic thermal behavior of building using phase change materials for latent heat storage

    Directory of Open Access Journals (Sweden)

    Selka Ghouti

    2015-01-01

    Full Text Available This study presents a two-dimensional model with a real size home composed of two-storey (ground and first floor spaces separated by a slab, enveloped by a wall with rectangular section containing phase change material (PCM in order to minimize energy consumption in the buildings. The main objective of the PCM-wall system is to decrease the temperature change from outdoor space before it reaches the indoor space during the daytime. The numerical approach uses effective heat capacity Ceff model with realistic outdoor climatic conditions of Tlemcen city, Algeria. The numerical results showed that by using PCM in wall as energy storage components may reduce the room temperature by about 6 to 7°C of temperature depending on the floor level (first floor spaces or ground floor spaces.

  17. Simultaneous Heat and Mass Transfer Model for Convective Drying of Building Material

    Science.gov (United States)

    Upadhyay, Ashwani; Chandramohan, V. P.

    2016-06-01

    A mathematical model of simultaneous heat and moisture transfer is developed for convective drying of building material. A rectangular brick is considered for sample object. Finite-difference method with semi-implicit scheme is used for solving the transient governing heat and mass transfer equation. Convective boundary condition is used, as the product is exposed in hot air. The heat and mass transfer equations are coupled through diffusion coefficient which is assumed as the function of temperature of the product. Set of algebraic equations are generated through space and time discretization. The discretized algebraic equations are solved by Gauss-Siedel method via iteration. Grid and time independent studies are performed for finding the optimum number of nodal points and time steps respectively. A MATLAB computer code is developed to solve the heat and mass transfer equations simultaneously. Transient heat and mass transfer simulations are performed to find the temperature and moisture distribution inside the brick.

  18. Experimental and Simulation of Gamma Radiation Dose Rate for High Exposure Building Material

    CERN Document Server

    Abbasi, Akbar

    2015-01-01

    Natural radioactivity concentrations in high exposure building materials are commonly used in Iran, which is measured a direct exposure by using {\\gamma}-ray spectrometry. The values for 226Ra, 232Th and 40K were in the ranges 3.8 - 94.2, 6.5 - 172.2 and 556.9 - 1539.2 Bqkg-1, respectively. The absorbed dose rates in the standard dwelling room due to 238U, 232Th series and 40K were calculated with MCNPX code. The simulation and experimental results were between 7.95 - 41.74 and 8.36 - 39.99 nGy h-1, respectively. These results were compared with experimental outing and there was overlap closely. The simulation results are able to develop for any kind of dwelling places.

  19. Virtual earthquake engineering laboratory with physics-based degrading materials on parallel computers

    Science.gov (United States)

    Cho, In Ho

    For the last few decades, we have obtained tremendous insight into underlying microscopic mechanisms of degrading quasi-brittle materials from persistent and near-saintly efforts in laboratories, and at the same time we have seen unprecedented evolution in computational technology such as massively parallel computers. Thus, time is ripe to embark on a novel approach to settle unanswered questions, especially for the earthquake engineering community, by harmoniously combining the microphysics mechanisms with advanced parallel computing technology. To begin with, it should be stressed that we placed a great deal of emphasis on preserving clear meaning and physical counterparts of all the microscopic material models proposed herein, since it is directly tied to the belief that by doing so, the more physical mechanisms we incorporate, the better prediction we can obtain. We departed from reviewing representative microscopic analysis methodologies, selecting out "fixed-type" multidirectional smeared crack model as the base framework for nonlinear quasi-brittle materials, since it is widely believed to best retain the physical nature of actual cracks. Microscopic stress functions are proposed by integrating well-received existing models to update normal stresses on the crack surfaces (three orthogonal surfaces are allowed to initiate herein) under cyclic loading. Unlike the normal stress update, special attention had to be paid to the shear stress update on the crack surfaces, due primarily to the well-known pathological nature of the fixed-type smeared crack model---spurious large stress transfer over the open crack under nonproportional loading. In hopes of exploiting physical mechanism to resolve this deleterious nature of the fixed crack model, a tribology-inspired three-dimensional (3d) interlocking mechanism has been proposed. Following the main trend of tribology (i.e., the science and engineering of interacting surfaces), we introduced the base fabric of solid

  20. Relationship between anode material, supporting electrolyte and current density during electrochemical degradation of organic compounds in water

    Energy Technology Data Exchange (ETDEWEB)

    Guzmán-Duque, Fernando L. [Grupo de diagnóstico y control de la contaminación, Facultad de ingeniería, Universidad de Antioquia, A.A. 1226, Medellín (Colombia); Palma-Goyes, Ricardo E. [Grupo de Investigación en Remediación Ambiental y Biocatálisis, Instituto de Química, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquía Udea, A.A. 1226, Medellín (Colombia); González, Ignacio [Universidad Autónoma Metropolitana-Iztapalapa, Departamento de Química, Av. San Rafael Atlixco No 186, C.P 09340, México D.F (Mexico); Peñuela, Gustavo [Grupo de diagnóstico y control de la contaminación, Facultad de ingeniería, Universidad de Antioquia, A.A. 1226, Medellín (Colombia); Torres-Palma, Ricardo A., E-mail: rtorres@matematicas.udea.edu.co [Grupo de Investigación en Remediación Ambiental y Biocatálisis, Instituto de Química, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquía Udea, A.A. 1226, Medellín (Colombia)

    2014-08-15

    Highlights: • Pathway and efficiency are linked to the current-electrode–electrolyte interaction. • Unlike BDD, IrO{sub 2} route was independent of current but dependent on the electrolyte. • IrO{sub 2}/SO{sub 4}{sup 2−} and IrO{sub 2}/Cl{sup −} routes were via IrO{sub 3} and chlorine species, respectively. • BDD/SO{sub 4}{sup 2−} and IrO{sub 2}/Cl{sup −} systems were favored at low and high currents, respectively. - Abstract: Taking crystal violet (CV) dye as pollutant model, the electrode, electrolyte and current density (i) relationship for electro-degrading organic molecules is discussed. Boron-doped diamond (BDD) or Iridium dioxide (IrO{sub 2}) used as anode materials were tested with Na{sub 2}SO{sub 4} or NaCl as electrolytes. CV degradation and generated oxidants showed that degradation pathways and efficiency are strongly linked to the current density-electrode–electrolyte interaction. With BDD, the degradation pathway depends on i: If i < the limiting current density (i{sub lim}), CV is mainly degraded by ·OH radicals, whereas if i > i{sub lim}, generated oxidants play a major role in the CV elimination. When IrO{sub 2} was used, CV removal was not dependent on i, but on the electrolyte. Pollutant degradation in Na{sub 2}SO{sub 4} on IrO{sub 2} seems to occur via IrO{sub 3}; however, in the presence of NaCl, degradation was dependent on the chlorinated oxidative species generated. In terms of efficiency, the Na{sub 2}SO{sub 4} electrolyte showed better results than NaCl when BDD anodes were employed. On the contrary, NaCl was superior when combined with IrO{sub 2}. Thus, the IrO{sub 2}/Cl{sup −} and BDD/SO{sub 4}{sup 2−} systems were better at removing the pollutant, being the former the most effective. On the other hand, pollutant degradation with the BDD/SO{sub 4}{sup 2−} and IrO{sub 2}/Cl{sup −} systems is favored at low and high current densities, respectively.

  1. Degradation mechanism of silicone glues under UV irradiation and options for designing materials with increased stability

    NARCIS (Netherlands)

    Fischer, H.R.; Semprimoschnig, C.; Mooney, C.; Rohr, T.; Eck, E.R.H. van; Verkuijlen, M.H.W.

    2013-01-01

    The degradation of silicone glues used, for example, in the assembly of solar modules for use in space, has been investigated and possible mechanisms which lead to colouration and possible embrittlement are analysed. Both effects are connected to the generation of radicals upon exposure to UV irradi

  2. Fatigue degradation and failure of rotating composite structures - Materials characterisation and underlying mechanisms

    DEFF Research Database (Denmark)

    Gamstedt, Kristofer; Andersen, Svend Ib Smidt

    2001-01-01

    The present review concerns rotating composite structures, in which fatigue degradation is of key concern for in-service failure. Such applications are for instance rotor blades in wind turbines, helicopter rotor blades, flywheels for energy storage,marine and aeronautical propellers, and rolls...

  3. Experimental measurements of thermal properties for Mexican building materials to simulate thermal behavior to save energy

    Energy Technology Data Exchange (ETDEWEB)

    Chavez-Galan, Jesus; Almanza, Rafael; Rodriguez, Neftali [Universidad Nacional Autonoma de Mexico (Mexico). Inst. de Ingenieria

    2008-07-01

    One of the main factors that determine the reliability of building's thermal design is the values of thermal and heat transfer properties used during this process. In order to optimizing such thermal design process, there is little information available of the most utilized building materials in Mexico; hence, some measurements were carried out. We present thermal conductivity experimental results for: red brick, tepetate, adobe and concrete. Furthermore, experimental data of convective heat transfer coefficients are reported on: red brick, tepetate, adobe and concrete walls. Kondratyev methodology was used for thermal conductivity estimations. Kondratyev methodology is based on the cooling off of bodies in regular state analysis. Thermal conductivity values were: red brick k{sub L} = 0.906 W/mC, tepetate k{sub T} = 0.648 W/mC, adobe k{sub A} = 0.570 W/mC, and concrete k{sub C} = 1.918 W/mC. Red brick, tepetate, adobe and concrete test walls of 0.46 x 0.56 and 0.06 m thick, were manufactured, as well as a prototype of testing for mounting the walls, in order to evaluate their convective heat transfer coefficients. Measurements were carried out at the Institute of Engineering-UNAM Wind-Tunnel, for an air velocities interval of 2-10 m/s. Reported values for convective coefficients fluctuate on 16-134 W/m{sup 2}2 C, depending on material and position wall, as well as air velocity. (orig.)

  4. Salt-enhanced chemical weathering of building materials and bacterial mineralization of calcium carbonate as a treatment

    Science.gov (United States)

    Schiro, M.; Ruiz-Agudo, E.; Jroundi, F.; Gonzalez-Muñoz, M. T.; Rodriguez-Navarro, C.

    2012-04-01

    Salt weathering is an important mechanism contributing to the degradation and loss of stone building materials. In addition to the physical weathering resulting from crystallization pressure, the presence of salts in solution greatly enhances the chemical weathering potential of pore waters. Flow through experiments quantify the dissolution rates of calcite and quartz grains (63-125 micrometer diameter) when subjected to 1.0 ionic strength solutions of MgSO4, MgCl, Na2SO4 or NaCl. Results indicate that the identity of the cation is the primary control over the dissolution rate of both calcite and quartz substrates, with salt-enhanced dissolution occurring most rapidly in Mg2+ bearing solutions. It has been observed that weathering rates of rocks in nature, as well as building stones, are slowed down by naturally occurring or artificially produced patinas. These tend to be bacterially produced, durable mineralized coatings that lend some degree of protection to the underlying stone surface [1]. Our research shows that bacterially produced carbonate coatings can be quite effective at reducing chemical weathering of stone by soluble salts. The calcite-producing-bacteria used in this study were isolated from stone monuments in Granada, Spain [2] and cultivated in an organic-rich culture medium on a variety of artificial and natural substrates (including limestone, marble, sandstone, quartz, calcite single crystals, glass cover-slips, and sintered porous glass). Scanning electron microscopy (FESEM) was used to image bacterial calcite growth and biofilm formation. In-situ atomic force microscopy (AFM) enabled calculation of dissolution rates of untreated and bacterially treated surfaces. 2D-XRD showed the mineralogy and crystallographic orientation of bacterial calcium carbonate. Results indicate that bacterially produced calcite crystals form a coherent, mechanically resistant surface layer in perfect crystallographic continuity with the calcite substrate (self

  5. Magnitude and timing of downstream channel aggradation and degradation in response to a dome-building eruption at Mount Hood, Oregon

    Science.gov (United States)

    Pierson, Thomas C.; Pringle, Patrick T.; Cameron, Kenneth A.

    2011-01-01

    A dome-building eruption at Mount Hood, Oregon, starting in A.D. 1781 and lasting until ca. 1793, produced dome-collapse lithic pyroclastic flows that triggered lahars and intermittently fed 108 m3 of coarse volcaniclastic sediment to sediment reservoirs in headwater canyons of the Sandy River. Mobilization of dominantly sandy sediment from these reservoirs by lahars and seasonal floods initiated downstream migration of a sediment wave that resulted in a profound cycle of aggradation and degradation in the lowermost reach of the river (depositional reach), 61-87 km from the source. Stratigraphic and sedimentologic relations in the alluvial fill, together with dendrochronologic dating of degradation terraces, demonstrate that (1) channel aggradation in response to sediment loading in the headwater canyons raised the river bed in this reach at least 23 m in a decade or less; (2) the transition from aggradation to degradation in the upper part of this reach roughly coincided with the end of the dome-building eruption; (3) fluvial sediment transport and deposition, augmented by one lahar, achieved a minimum average aggradation rate of ~2 m/yr; (4) the degradation phase of the cycle was more prolonged than the aggradation phase, requiring more than half a century for the river to reach its present bed elevation; and (5) the present longitudinal profile of the Sandy River in this reach is at least 3 m above the pre-eruption profile. The pattern and rate of channel response and recovery in the Sandy River following heavy sediment loading resemble those of other rivers similarly subjected to very large sediment inputs. The magnitude of channel aggradation in the lower Sandy River, greater than that achieved at other volcanoes following much larger eruptions, was likely enhanced by lateral confinement of the channel within a narrow incised valley. A combination of at least one lahar and winter floods from frequent moderate-magnitude rainstorms and infrequent very large

  6. Test methods and reduction of organic pollutant compound emissions from wood-based building and furniture materials.

    Science.gov (United States)

    Kim, Sumin; Choi, Yoon-Ki; Park, Kyung-Won; Kim, Jeong Tai

    2010-08-01

    This paper reviews different methods for the analysis of formaldehyde and volatile organic compounds (VOCs) from wood-based panel materials for furniture and building interiors and highlights research on reduction of emission from wood-based panels that can adversely affect indoor air quality. In Korea, standard test methods have been developed to determine formaldehyde and VOC emissions from building products, and the Ministry of Environment regulates the use of building materials with pollutant emissions. Desiccator and perforator methods are being used for formaldehyde and the chamber and field and laboratory emission cell (FLEC) methods for VOC and formaldehyde emissions. The VOC analyzer is a suitable pre-test method for application as a total VOC (TVOC) emission test and bake-out is a useful method to reduce TVOC and formaldehyde emissions from furniture materials in indoor environments.

  7. Recycling waste brick from construction and demolition of buildings as pozzolanic materials.

    Science.gov (United States)

    Lin, Kae-Long; Wu, Hsiu-Hsien; Shie, Je-Lueng; Hwang, Chao-Lung; An Cheng

    2010-07-01

    This investigation elucidates the pozzolic characteristics of pastes that contain waste brick from building construction and demolition wastes. The TCLP leaching concentrations of waste brick for the target cations or heavy metals were all lower than the current regulatory thresholds of the Taiwan EPA. Waste brick had a pozzolanic strength activity index of 107% after 28 days. It can be regarded as a strong pozzolanic material. The compressive strengths of waste brick blended cement (WBBC) that contain 10% waste brick increased from 71.2 MPa at 28 days to 75.1 MPa at 60 days, an increase of approximately 5% over that period. At 28 days, the pozzolanic reaction began, reducing the amount of Ca(OH)(2) and increasing the densification. The intensity of the peak at 3640 cm(- 1) associated with Ca(OH)(2) is approximately the same for ordinary Portland cement (OPC) pastes. The hydration products of all the samples yield characteristics peaks at 978 cm(-1) associated with C-S-H, and at ~3011 cm(-1) and 1640 cm(-1) associated with water. The samples yield peaks at 1112 cm(-1), revealing the formation of ettringite. In WBBC pastes, the ratio Q(2)/Q(1) increases with curing time. These results demonstrate that increasing the curing time increases the number of linear polysilicate anions in C-S-H. Experimental results reveal that waste brick has potential as a pozzolanic material in the partial replacement of cement.

  8. Effect of water-ice phase change on thermal performance of building materials

    Science.gov (United States)

    Kočí, Václav; Černý, Robert

    2016-07-01

    The effect of water ice-phase change on thermal performance of integrated building material is investigated in this paper. As a characteristic construction, simple external wall made of aerated autoclaved concrete was assumed which was exposed to dynamic climatic condition of Šerák, Czech Republic. The computational modelling of hygrothermal performance was carried out using computer codes HEMOT and SIFEL that work on the basis of finite element method. The effect of phase change was taken into account by fixed-domain method, when experimentally determined effective specific heat capacity was used as a material parameter. It comprises also the effect of heat consumption and heat release that accompany the water-ice phase change. Comparing to the results with specific heat capacity, the effect of phase change on thermal performance could be quantified. The results showed that temperature fields can differ more than 6 °C. Additionally, the amount energy transported through the wall may be higher up to 4 %. This confirmed, that the effect water-ice phase change should be included in all the relevant energy calculations.

  9. Absorption cross section of building materials at mm wavelength in a reverberation chamber

    Science.gov (United States)

    Micheli, D.; Delfini, A.; Pastore, R.; Marchetti, M.; Diana, R.; Gradoni, G.

    2017-02-01

    The reverberation chamber (RC) method is used to estimate the average absorption cross section of building materials at mm wave frequencies. Analysed samples include concrete, travertine and bricks of different types. The investigation is carried out in the frequency range between 50 GHz and 68 GHz, which is of interest in the next generation of mobile telecommunication system. A cylindrical cavity is transformed into a RC through the use of a mechanical model stirrer. The chamber field is statistically homogeneous and depolarized; therefore it can be used to probe the average response of the sample under test. In particular, through a differential measure of the average quality factor (average insertion loss) it is possible estimate the fraction of power absorbed by the sample under test. Several cube-shape samples have been characterized and compared. Obtained results show that analysed samples have remarkably different levels of the electromagnetic wave absorption, depending on both material density and chemical composition. The absorption of pure water is used as a baseline to determine the dynamic range of the measurement.

  10. Application of Bayer red mud for iron recovery and building material production from alumosilicate residues.

    Science.gov (United States)

    Liu, Wanchao; Yang, Jiakuan; Xiao, Bo

    2009-01-15

    Red mud is a solid waste produced in the process of alumina extraction from bauxite. In this paper, recovery iron from Bayer red mud was studied with direct reduction roasting process followed by magnetic separation, and then building materials were prepared from alumosilicate residues. After analysis of chemical composition and crystalline phase, the effects of different parameters on recovery efficiency of iron were carried out. The optimum reaction parameters were proposed as the following: ratio of carbon powder: red mud at 18:100, ratio of additives: red mud at 6:100, roasting at 1300 degrees C for 110min. With these optimum parameters, total content of iron in concentrated materials was 88.77%, metallization ratio of 97.69% and recovery ratio of 81.40%. Then brick specimens were prepared with alumosilicate residues and hydrated lime. Mean compressive strength of specimens was 24.10MPa. It was indicated that main mineral phase transformed from nepheline (NaAlSiO4) in alumosilicate residues to gehlenite (Ca2Al2SiO7) in brick specimens through X-ray diffraction (XRD) technology. The feasibility of this transformation under the experimental conditions was proved by thermodynamics calculation analysis. Combined the recovery of iron with the reuse of alumosilicate residues, it can realize zero-discharge of red mud from Bayer process.

  11. Use of industrial waste for the manufacturing of sustainable building materials.

    Science.gov (United States)

    Sugrañez, Rafael; Cruz-Yusta, Manuel; Mármol, Isabel; Martín, Francisco; Morales, Julián; Sánchez, Luis

    2012-04-01

    Presently, appropriate waste management is one of the main requisites for sustainable development; this task is tackled by the material construction industry. The work described herein is focused on the valorization of granite waste through incorporation, as a filler-functional admixture, into cement-based mortar formulations. The main components of the waste are SiO(2) (62.1 %), Al(2)O(3) (13.2 %), Fe(2)O(3) (10.1 %), and CaO (4.6 %). The presence of iron oxides is used to develop the photocatalytic properties of the waste. Following heating at 700 °C, α-Fe(2)O(3) forms in the waste. The inclusion of the heated sample as a filler admixture in a cement-based mortar is possible. Moreover, this sample exhibits a moderate ability in the photodegradation of organic dye solutions. Also, the plastering mortars, in which the heated samples have been used, show self-cleaning properties. The preparation of sustainable building materials is demonstrated through the adequate reuse of the granite waste.

  12. Degradation of proton depth dose distributions attributable to microstructures in lung-equivalent material

    Energy Technology Data Exchange (ETDEWEB)

    Titt, Uwe, E-mail: utitt@mdanderson.org; Mirkovic, Dragan; Mohan, Radhe [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas 77030 (United States); Sell, Martin [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas 77030 and Department of Medical Physics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120 (Germany); Unkelbach, Jan [Department of Radiation Oncology, Massachusetts General Hospital, 55 Fruit Street, Boston, Massachusetts 02114 (United States); Bangert, Mark [Department of Medical Physics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120 (Germany); Oelfke, Uwe [Department of Medical Physics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany and Department of Physics, The Institute of Cancer Research, 123 Old Brompton Road, London SW7 3RP (United Kingdom)

    2015-11-15

    Purpose: The purpose of the work reported here was to investigate the influence of sub-millimeter size heterogeneities on the degradation of the distal edges of proton beams and to validate Monte Carlo (MC) methods’ ability to correctly predict such degradation. Methods: A custom-designed high-resolution plastic phantom approximating highly heterogeneous, lung-like structures was employed in measurements and in Monte Carlo simulations to evaluate the degradation of proton Bragg curves penetrating heterogeneous media. Results: Significant differences in distal falloff widths and in peak dose values were observed in the measured and the Monte Carlo simulated curves compared to pristine proton Bragg curves. Furthermore, differences between simulations of beams penetrating CT images of the phantom did not agree well with the corresponding experimental differences. The distal falloff widths in CT image-based geometries were underestimated by up to 0.2 cm in water (corresponding to 0.8–1.4 cm in lung tissue), and the peak dose values of pristine proton beams were overestimated by as much as ~35% compared to measured curves or depth-dose curves simulated on the basis of true geometry. The authors demonstrate that these discrepancies were caused by the limited spatial resolution of CT images that served as a basis for dose calculations and lead to underestimation of the impact of the fine structure of tissue heterogeneities. A convolution model was successfully applied to mitigate the underestimation. Conclusions: The results of this study justify further development of models to better represent heterogeneity effects in soft-tissue geometries, such as lung, and to correct systematic underestimation of the degradation of the distal edge of proton doses.

  13. Evaluation of three common green building materials for ozone removal, and primary and secondary emissions of aldehydes

    Science.gov (United States)

    Gall, Elliott; Darling, Erin; Siegel, Jeffrey A.; Morrison, Glenn C.; Corsi, Richard L.

    2013-10-01

    Ozone reactions that occur on material surfaces can lead to elevated concentrations of oxidized products in the occupied space of buildings. However, there is little information on the impact of materials at full scale, especially for green building materials. Experiments were completed in a 68 m3 climate-controlled test chamber with three certified green building materials that can cover large areas in buildings: (1) recycled carpet, (2) perlite-based ceiling tile and (3) low-VOC paint and primer on recycled drywall. Ozone deposition velocity and primary and secondary emission rates of C1 to C10 saturated carbonyls were determined for two chamber mixing conditions and three values of relative humidity. A direct comparison was made between ozone deposition velocities and carbonyl yields observed for the same materials analyzed in small (10 L) chambers. Total primary carbonyl emission rates from carpet, ceiling tile and painted drywall ranged from 27 to 120 μg m-2 h-1, 13 to 40 μg m-2 h-1, 3.9 to 42 μg m-2 h-1, respectively. Ozone deposition velocity to these three materials averaged 6.1 m h-1, 2.3 m h-1 and 0.32 m h-1, respectively. Total secondary carbonyl emissions from these materials ranged from 70 to 276 μg m-2 h-1, 0 to 12 μg m-2 h-1, and 0 to 30 μg m-2 h-1, respectively. Carbonyl emissions were determined with a transient approximation, and were found to be in general agreement with those found in the literature. These results suggest that care should be taken when selecting green building materials due to potentially large differences in primary and secondary emissions.

  14. E-Area Vault Concrete Material Property And Vault Durability/Degradation Projection Recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Phifer, M. A.

    2014-03-11

    Subsequent to the 2008 E-Area Low-Level Waste Facility (ELLWF) Performance Assessment (PA) (WSRC 2008), two additional E-Area vault concrete property testing programs have been conducted (Dixon and Phifer 2010 and SIMCO 2011a) and two additional E-Area vault concrete durability modeling projections have been made (Langton 2009 and SIMCO 2012). All the information/data from these reports has been evaluated and consolidated herein by the Savannah River National Laboratory (SRNL) at the request of Solid Waste Management (SWM) to produce E-Area vault concrete hydraulic and physical property data and vault durability/degradation projection recommendations that are adequately justified for use within associated Special Analyses (SAs) and future PA updates. The Low Activity Waste (LAW) and Intermediate Level (IL) Vaults structural degradation predictions produced by Carey 2006 and Peregoy 2006, respectively, which were used as the basis for the 2008 ELLWF PA, remain valid based upon the results of the E-Area vault concrete durability simulations reported by Langton 2009 and those reported by SIMCO 2012. Therefore revised structural degradation predictions are not required so long as the mean thickness of the closure cap overlying the vaults is no greater than that assumed within Carey 2006 and Peregoy 2006. For the LAW Vault structural degradation prediction (Carey 2006), the mean thickness of the overlying closure cap was taken as nine feet. For the IL Vault structural degradation prediction (Peregoy 2006), the mean thickness of the overlying closure cap was taken as eight feet. The mean closure cap thicknesses as described here for both E-Area Vaults will be included as a key input and assumption (I&A) in the next revision to the closure plan for the ELLWF (Phifer et al. 2009). In addition, it has been identified as new input to the PA model to be assessed in the ongoing update to the new PA Information UDQE (Flach 2013). Once the UDQE is approved, the SWM Key I

  15. Stability of CIGS Solar Cells and Component Materials Evaluated by a Step-Stress Accelerated Degradation Test Method: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Pern, F. J.; Noufi, R.

    2012-10-01

    A step-stress accelerated degradation testing (SSADT) method was employed for the first time to evaluate the stability of CuInGaSe2 (CIGS) solar cells and device component materials in four Al-framed test structures encapsulated with an edge sealant and three kinds of backsheet or moisture barrier film for moisture ingress control. The SSADT exposure used a 15oC and then a 15% relative humidity (RH) increment step, beginning from 40oC/40%RH (T/RH = 40/40) to 85oC/70%RH (85/70) as of the moment. The voluminous data acquired and processed as of total DH = 3956 h with 85/70 = 704 h produced the following results. The best CIGS solar cells in sample Set-1 with a moisture-permeable TPT backsheet showed essentially identical I-V degradation trend regardless of the Al-doped ZnO (AZO) layer thickness ranging from standard 0.12 μm to 0.50 μm on the cells. No clear 'stepwise' feature in the I-V parameter degradation curves corresponding to the SSADT T/RH/time profile was observed. Irregularity in I-V performance degradation pattern was observed with some cells showing early degradation at low T/RH < 55/55 and some showing large Voc, FF, and efficiency degradation due to increased series Rs (ohm-cm2) at T/RH ≥ 70/70. Results of (electrochemical) impedance spectroscopy (ECIS) analysis indicate degradation of the CIGS solar cells corresponded to increased series resistance Rs (ohm) and degraded parallel (minority carrier diffusion/recombination) resistance Rp, capacitance C, overall time constant Rp*C, and 'capacitor quality' factor (CPE-P), which were related to the cells? p-n junction properties. Heating at 85/70 appeared to benefit the CIGS solar cells as indicated by the largely recovered CPE-P factor. Device component materials, Mo on soda lime glass (Mo/SLG), bilayer ZnO (BZO), AlNi grid contact, and CdS/CIGS/Mo/SLG in test structures with TPT showed notable to significant degradation at T/RH ≥ 70/70. At T/RH = 85/70, substantial blistering of

  16. Environmental Impact Assessment of a School Building in Iceland Using LCA-Including the Effect of Long Distance Transport of Materials

    OpenAIRE

    Nargessadat Emami; Björn Marteinsson; Jukka Heinonen

    2016-01-01

    Buildings are the key components of urban areas and society as a complex system. A life cycle assessment was applied to estimate the environmental impacts of the resources applied in the building envelope, floor slabs, and interior walls of the Vættaskóli-Engi building in Reykjavik, Iceland. The scope of this study included four modules of extraction and transportation of raw material to the manufacturing site, production of the construction materials, and transport to the building site, as d...

  17. Combining 3-dimensional degradable electrostatic spinning scaffold and dental follicle cells to build peri-implant periodontium

    Directory of Open Access Journals (Sweden)

    Ximu Zhang

    2013-01-01

    Full Text Available Introduction: Some inevitable problems, such as concentrated bite force and lacked ability of self-renewal, are proved to be the major challenge in the management of implants failures. Thus, it is meaningful to find an ideal dental implant harboring its own peri-implant periodontium, just as the natural teeth. Various studies attempted to reconstruct the periodontium around implants, but unfortunately, it was previously revealed that the artificial periodotium around implants was just a wilderness of fibers, while without the physiological function of natural periodontium, like sensory and homeostatic. The Hypothesis: In this paper, we propose a hypothesis that a modified three-dimensional scaffold with reconstructed peri-implant tissues can be a network for stem cells differentiation. After seeded on the scaffold, stem cells produce various growth factors and differentiate to different orientations in places necessary. This hypothesis, if proven to be valid, will offer a novel and effective therapy for the restoration of missing teeth by implant. Evaluation of the Hypothesis: The scaffold involves three different tissues. Though degradation rate of electrospinning scaffold is under control, its degradation rate should be in consistent with the generation of three tissues. Therefore, the relative experiments are necessary to define the best rate of degradation. Further verification is necessary to check whether the rebuilt cementum, bone and periodontium are strong enough to keep the implant stable and maintain its function.

  18. Impact of reaction products from building materials and furnishings on indoor air quality—A review of recent advances in indoor chemistry

    Science.gov (United States)

    Uhde, E.; Salthammer, T.

    The variety of chemical substances present in modern building products, household products and furnishings provides potential for chemical reactions in the material (case 1), on the material surface (case 2) and in the gas phase (case 3). Such "indoor chemistry" is known as one of the main reasons for primary and secondary emissions. The conditions of production often cause unwanted side reactions and a number of new compounds can be found in finished products. Elevated temperatures are responsible for the degradation of cellulose, decomposition of non-heat-resistant additives and other thermally induced reactions like Diels-Alder synthesis. Heterogeneous chemistry takes place on the surface of materials. Well-known examples are the formation of aliphatic aldehydes from the oxidation of unsaturated fatty acids or the cleavage of photoinitiators under the influence of light. In case of composite flooring structures hydrolysis is one of the major pathways for the appearance of alcohols from esters. If different kinds of material are fixed together, emissions of new VOCs formed by inter-species reactions are possible. Other indoor air pollutants are formed by rearrangement of cleavage products or by metabolism. Compounds with -C dbnd C- bonds like terpenes, styrene, 4-phenylcyclohexene, etc. undergo gas phase reactions with O 3, NO x, OH and other reactive gases. It has been shown that such products derived from indoor-related reactions may have a negative impact on indoor air quality due to their low odor threshold or health-related properties. Therefore, the understanding of primary and secondary emissions and the chemical processes behind is essential for the evaluation of indoor air quality. This publication gives an overview on the current state of research and new findings regarding primary and secondary emissions from building products and furnishings.

  19. Stability of CIGS solar cells and component materials evaluated by a step-stress accelerated degradation test method

    Science.gov (United States)

    Pern, F. J.; Noufi, R.

    2012-10-01

    A step-stress accelerated degradation testing (SSADT) method was employed for the first time to evaluate the stability of CuInGaSe2 (CIGS) solar cells and device component materials in four Al-framed test structures encapsulated with an edge sealant and three kinds of backsheet or moisture barrier film for moisture ingress control. The SSADT exposure used a 15°C and then a 15% relative humidity (RH) increment step, beginning from 40°C/40%RH (T/RH = 40/40) to 85°C/70%RH (85/70) as of the moment. The voluminous data acquired and processed as of total DH = 3956 h with 85/70 = 704 h produced the following results. The best CIGS solar cells in sample Set-1 with a moisture-permeable TPT backsheet showed essentially identical I-V degradation trend regardless of the Al-doped ZnO (AZO) layer thickness ranging from standard 0.12 μm to 0.50 μm on the cells. No clear "stepwise" feature in the I-V parameter degradation curves corresponding to the SSADT T/RH/time profile was observed. Irregularity in I-V performance degradation pattern was observed with some cells showing early degradation at low T/RH = 70/70. Results of (electrochemical) impedance spectroscopy (ECIS) analysis indicate degradation of the CIGS solar cells corresponded to increased series resistance Rs (ohm) and degraded parallel (minority carrier diffusion/recombination) resistance Rp, capacitance C, overall time constant Rp*C, and "capacitor quality" factor (CPE-P), which were related to the cells' p-n junction properties. Heating at 85/70 appeared to benefit the CIGS solar cells as indicated by the largely recovered CPE-P factor. Device component materials, Mo on soda lime glass (Mo/SLG), bilayer ZnO (BZO), AlNi grid contact, and CdS/CIGS/Mo/SLG in test structures with TPT showed notable to significant degradation at T/RH >= 70/70. At T/RH = 85/70, substantial blistering of BZO layers on CIGS cell pieces was observed that was not seen on BZO/glass, and a CdS/CIGS sample displayed a small darkening and then

  20. [Evaluation of the migration of contaminants from building materials produced on the base of blast-furnace slags].

    Science.gov (United States)

    Pugin, K G; Vaysman, Ya I

    2014-01-01

    There is experimentally established the change of the migratory activity of pollutants from building materials produced from blast furnace slag throughout their life cycle in the form of a nonlinear wave-like nature as there are appeared newly opened surfaces of a contact with aggressive waters in the process of gradual crushing of materials as a result of destructive mechanical effects on him and corrosive waters with varying pH values. There are established regularities of the migration activity ofpollutants (on the example of heavy metals) as directly dependent on the newly opening surface of the contact of the material with water having a various pH value. There is shown an expediency of introduction of alterations in the procedure for sanitary hygienic assessment of building materials with the addition of industrial waste (Methodical Instructions 2.1.674-97), allowing to take into account the migration of contaminants from them throughout the life cycle.

  1. Stepwise transformation of the molecular building blocks in a porphyrin-encapsulating metal-organic material

    KAUST Repository

    Zhang, ZhenJie

    2013-04-24

    When immersed in solutions containing Cu(II) cations, the microporous metal-organic material P11 ([Cd4(BPT)4]·[Cd(C 44H36N8)(S)]·[S], BPT = biphenyl-3,4′,5-tricarboxylate) undergoes a transformation of its [Cd 2(COO)6]2- molecular building blocks (MBBs) into novel tetranuclear [Cu4X2(COO)6(S) 2] MBBs to form P11-Cu. The transformation occurs in single-crystal to single-crystal fashion, and its stepwise mechanism was studied by varying the Cd2+/Cu2+ ratio of the solution in which crystals of P11 were immersed. P11-16/1 (Cd in framework retained, Cd in encapsulated porphyrins exchanged) and other intermediate phases were thereby isolated and structurally characterized. P11-16/1 and P11-Cu retain the microporosity of P11, and the relatively larger MBBs in P11-Cu permit a 20% unit cell expansion and afford a higher surface area and a larger pore size. © 2013 American Chemical Society.

  2. Increasing energy efficiency of HVAC systems of buildings using phase change material

    Energy Technology Data Exchange (ETDEWEB)

    Chusak, Lee; Daiber, Jared; Agarwal, Ramesh [Department of Mechanical Engineering and Materials Science, Washington University in St. Louis, St. Louis, MO 63130 (United States)

    2012-07-01

    Using Computational Fluid Dynamics (CFD), four different cooling systems used in contemporary office environments are modeled to compare energy consumption and thermal comfort levels. Incorporating convection and radiation technologies, full-scale models of an office room compare energy efficiency of (a) an all-air overhead system, (b) a combined all-air overhead and hydronic radiant system (chilled ceiling), (c) an all-air raised floor system (displacement ventilation), and (d) a combined displacement ventilation with a chilled ceiling. The computational domain for each model consists of one temperature varying wall (simulating the temperature of the exterior wall of the building during a 24-hour period) and adiabatic conditions for the remaining walls, floor, and ceiling (simulating interior walls of the room). Two sets of computations are conducted. The first set considers a glass window and plastic shade configuration for the exterior wall. The second set of computations includes a phase change material layer between the glass window and the plastic shade. Results show substantial energy savings can be accrued using the displacement ventilation and especially the displacement ventilation with a chilled ceiling over the conventional overhead mixing ventilation system. The results also show that the addition of a PCM layer to the exterior wall can significantly decrease the cooling energy requirements.

  3. Research on the additives to reduce radioactive pollutants in the building materials containing fly ash.

    Science.gov (United States)

    He, Deng-liang; Yin, Guang-fu; Dong, Fa-qin; Liu, Lai-bao; Luo, Ya-jun

    2010-05-15

    Several kinds of functional additives such as barite, zeolite, ferric oxide, gypsum, and high alumina cement were introduced to prepare a low-radiation cement-based composite to reduce radioactive pollutants contained in fly ash. The effect of content and granularity of the functional additives on the release of radioactive pollutants were investigated. Composites were characterized by X-ray diffraction, Scan electron microscopy. The results indicate that the radioactive pollutants contained in the fly ash can be reduced by adding a proper amount of zeolite, ferric oxide, gypsum, and high alumina cement. The release of radon from fly ash decreases with a decrease in the granularity of additives. Compared with traditional cement-based composite containing fly ash, the release of radon can be reduced 64.8% in these composites, and the release of gamma-ray is decreased 45%. Based on the microstructure and phase analysis, we think that by added functional additives, there are favorable to form self-absorption of radioactivity in the interior composites. This cement-based composite will conducive to fly ash are large-scale applied in the field of building materials.

  4. Studies on use of Copper Slag as Replacement Material for River Sand in Building Constructions

    Science.gov (United States)

    Madheswaran, C. K.; Ambily, P. S.; Dattatreya, J. K.; Rajamane, N. P.

    2014-09-01

    This work focuses on the use of copper slag, as a partial replacement of sand for use in cement concrete and building construction. Cement mortar mixtures prepared with fine aggregate made up of different proportions of copper slag and sand were tested for use as masonry mortars and plastering. Three masonry wall panels of dimensions 1 × 1 m were plastered. The studies showed that although copper slag based mortar is suitable for plastering, with the increase in copper slag content, the wastage due to material rebounding from the plastered surfaces increases. It is therefore suggested that the copper slag can be used for plastering of floorings and horizontal up to 50 % by mass of the fine aggregate, and for vertical surfaces, such as, brick/block walls it can be used up to 25 %. In this study on concrete mixtures were prepared with two water cement ratios and different proportions of copper slag ranging from 0 % (for the control mix) to 100 % of fine aggregate. The Concrete mixes were evaluated for workability, density, and compressive strength.

  5. Increasing energy efficiency of HVAC systems of buildings using phase change material

    Directory of Open Access Journals (Sweden)

    Lee Chusak, Jared Daiber, Ramesh Agarwal

    2012-01-01

    Full Text Available Using Computational Fluid Dynamics (CFD, four different cooling systems used in contemporary office environments are modeled to compare energy consumption and thermal comfort levels. Incorporating convection and radiation technologies, full-scale models of an office room compare energy efficiency of (a an all-air overhead system, (b a combined all-air overhead and hydronic radiant system (chilled ceiling, (c an all-air raised floor system (displacement ventilation, and (d a combined displacement ventilation with a chilled ceiling. The computational domain for each model consists of one temperature varying wall (simulating the temperature of the exterior wall of the building during a 24-hour period and adiabatic conditions for the remaining walls, floor, and ceiling (simulating interior walls of the room. Two sets of computations are conducted. The first set considers a glass window and plastic shade configuration for the exterior wall. The second set of computations includes a phase change material layer between the glass window and the plastic shade. Results show substantial energy savings can be accrued using the displacement ventilation and especially the displacement ventilation with a chilled ceiling over the conventional overhead mixing ventilation system. The results also show that the addition of a PCM layer to the exterior wall can significantly decrease the cooling energy requirements.

  6. HYGRO-THERMAL BEHAVIOUR OF POROUS BUILDING MATERIAL SUBJECTED TO DIFFERENT EXTERNAL TEMPERATURE AND HUMIDITY CONDITIONS

    Directory of Open Access Journals (Sweden)

    ALI CHIKHI

    2016-04-01

    Full Text Available This work is focused on the behaviour of a block of cement mortar, subjected to variable external temperature and humidity conditions. The porous building material sample is fitted inside a box, in which a heat exchanger is connected to a thermostatic bath. Three sequences of measurement are considered: (i the response of the sample, when variations of temperature are applied; (ii the air ranging between the exchanger and the non-isolated face of the mortar is continuously humidified, by injecting of sprayed water; (iii the effect of simultaneously variation on temperature and humidity. A mathematical model representative of heat and mass transfer, in multiphasic medium (cement mortar, is developed in order to confront experimental and numerical results. Displacements of moisture and temperature fronts are observed and discussed. This study would enable us to understand the hygro-thermal behaviour of construction walls, to make an adequate design according to the climatic parameters and thus to improve the control of the energy used for heating.

  7. A Proof of Concept: Grizzly, the LWRS Program Materials Aging and Degradation Pathway Main Simulation Tool

    Energy Technology Data Exchange (ETDEWEB)

    Ben Spencer; Jeremey Busby; Richard Martineau; Brian Wirth

    2012-10-01

    Nuclear power currently provides a significant fraction of the United States’ non-carbon emitting power generation. In future years, nuclear power must continue to generate a significant portion of the nation’s electricity to meet the growing electricity demand, clean energy goals, and ensure energy independence. New reactors will be an essential part of the expansion of nuclear power. However, given limits on new builds imposed by economics and industrial capacity, the extended service of the existing fleet will also be required.

  8. National survey on the natural radioactivity and Rn-222 exhalation rate of building materials in the Netherlands

    NARCIS (Netherlands)

    de Jong, P.; van Dijk, W.; van der Graaf, E.R.; de Groot, A.V.

    2006-01-01

    The present study reports on results of a nationwide survey on the natural radioactivity concentrations and Rn-222 exhalation rates of the prevailing building materials in the Netherlands. In total 100 samples were taken and analyzed for the activity concentrations of Ra-226, Ra-228, Th-228, and K-4

  9. Effect of ventilation on perceived quality of air polluted by building materials. A summary of reported data

    Energy Technology Data Exchange (ETDEWEB)

    Wargocki, P.; Vondruskova, J. (International Centre for Indoor Environment and Energy, Dept. of Mechanical Engineering, DTU, Kgs. Lyngby (DK)); Knudsen, Henrik N. (Danish Building Research Institute, Aalborg Univ., Hoersholm (DK))

    2007-02-15

    This paper summarizes existing data on how varying ventilation rates affect the perceived quality of air polluted by building materials. This is done by reviewing literature dealing with exposure-response relationships, i.e. the log-linear relationships between the concentration of pollutants (exposure) and the perceived air quality (response). The reviewed data originate from studies with single building materials performed in small-scale ventilated chambers and from studies carried out in a full-scale setting resembling normal offices. Perceived air quality expressed in terms of acceptability as assessed by untrained panels was included. The results show that the exposure-response relationships vary for different building materials as regards the impact of changing ventilation rate on perceived air quality and the level of perceived air quality at a constant ventilation rate. This applies both for the data collected in small-scale and in full-scale experiments. The differences may be caused by the experimental conditions, psychological factors, physiological factors, and chemical/physical factors. A well controlled study taking these factors into account with several different building materials, is thus recommended to further study whether the observed results have practical significance. These experiments should be carried out under realistic fullscale conditions. (au)

  10. A COMPARATIVE STUDY OF THE THERMAL COMFORT OF DIFFERENT BUILDING MATERIALS IN SANA’A

    Directory of Open Access Journals (Sweden)

    Mousa Ahmed Alhaddad

    2013-01-01

    Full Text Available This study describes the impact of alternative building material envelope systems on the overall thermal performance of four selected materials used in Sana’a, Yemen. These systems included adobe, brick, stone and concrete block. After thorough on-site investigation and data collection, the information, along with regional weather data were input into the Ecotect energy simulation software for thermal performance evaluation. The objective was to search for affordable and energy-efficient construction techniques suitable for settlements and incorporating traditional cultural values in a arid upland region characterized by cold winters and warm, dry summers. This was pursued by analyzing temperature and measurements within buildings constructed from a variety of traditional and modern materials. The thermal behavior and comfort, the patterns of energy use and the appropriateness of the different building techniques and materials are analyzed, compared and discussed. We demonstrate how a building envelope reacts to outdoor conditions through graphic illustration and show ways in which the research can be extended by the creation of simulations using Ecotect software. This research contributes to the promotion of passive and low energy architecture towards a sustainable future.

  11. The Building Blocks of Digital Media Literacy: Socio-Material Participation and the Production of Media Knowledge

    Science.gov (United States)

    Dezuanni, Michael

    2015-01-01

    This article outlines the knowledge and skills students develop when they engage in digital media production and analysis in school settings. The metaphor of "digital building blocks" is used to describe the material practices, conceptual understandings and production of knowledge that lead to the development of digital media literacy.…

  12. Nano-coatings Used in Building Materials%建筑纳米涂料崭露头角

    Institute of Scientific and Technical Information of China (English)

    杨忠敏

    2012-01-01

    To introduce the definition,application,status quo,properties,and market prospect of nano-coatings used in building materials.%介绍建筑纳米涂料定义,应用现状,性能优势和市场前景。

  13. The Use of Building Materials in Landscape%建筑材料在园林中的运用

    Institute of Scientific and Technical Information of China (English)

    王天予

    2011-01-01

    Using of materials in modern gardens still has some problems, such as the short life of materials, being difficult in maintenance, unrecyclable, not enough ecological and environmental protection, etc., while using new materials is an important means to solve these problems. Many building materials can be used as new materials of landscape, including native materials, new high-tech materials, recycle and reuse of construction waste, etc. The current use of landscape materials is analyzed in this paper, and how to use a variety of building materials in landscape is discussed and learned through studies of actual cases.%现代园林材料在使用中存在一些问题,如材料寿命短、不易养护、不能回收、不够生态环保等.使用新材料是解决这些问题的重要手段,而很多建筑材料在园林中能作为新材料被利用,包括乡土材料、新型高科技材料、建筑废弃物的回收再利用等.分析当前的园林材料使用情况,通过实际的案例分析,讨论并学习如何在园林中使用各种建筑材料.

  14. Probabilistic Material Strength Degradation Model for Inconel 718 Components Subjected to High Temperature, Mechanical Fatigue, Creep and Thermal Fatigue Effects

    Science.gov (United States)

    Bast, Callie Corinne Scheidt

    1994-01-01

    This thesis presents the on-going development of methodology for a probabilistic material strength degradation model. The probabilistic model, in the form of a postulated randomized multifactor equation, provides for quantification of uncertainty in the lifetime material strength of aerospace propulsion system components subjected to a number of diverse random effects. This model is embodied in the computer program entitled PROMISS, which can include up to eighteen different effects. Presently, the model includes four effects that typically reduce lifetime strength: high temperature, mechanical fatigue, creep, and thermal fatigue. Statistical analysis was conducted on experimental Inconel 718 data obtained from the open literature. This analysis provided regression parameters for use as the model's empirical material constants, thus calibrating the model specifically for Inconel 718. Model calibration was carried out for four variables, namely, high temperature, mechanical fatigue, creep, and thermal fatigue. Methodology to estimate standard deviations of these material constants for input into the probabilistic material strength model was developed. Using the current version of PROMISS, entitled PROMISS93, a sensitivity study for the combined effects of mechanical fatigue, creep, and thermal fatigue was performed. Results, in the form of cumulative distribution functions, illustrated the sensitivity of lifetime strength to any current value of an effect. In addition, verification studies comparing a combination of mechanical fatigue and high temperature effects by model to the combination by experiment were conducted. Thus, for Inconel 718, the basic model assumption of independence between effects was evaluated. Results from this limited verification study strongly supported this assumption.

  15. Task 1. Monitoring real time materials degradation. NRC extended In-situ and real-time Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Bakhtiari, Sasan [Argonne National Lab. (ANL), Argonne, IL (United States)

    2012-03-01

    The overall objective of this project was to perform a scoping study to identify, in concert with the nuclear industry, those sensors and techniques that have the most promising commercial viability and fill a critical inspection or monitoring need. Candidates to be considered include sensors to monitor real-time material degradation, characterize residual stress, monitor and inspect component fabrication, assess radionuclide and associated chemical species concentrations in ground water and soil, characterize fuel properties, and monitor severe accident conditions. Under Task 1—Monitoring Real-Time Materials Degradation—scoping studies were conducted to assess the feasibility of potential inspection and monitoring technologies (i.e., a combination of sensors, advanced signal processing techniques, and data analysis methods) that could be utilized in LWR and/or advanced reactor applications for continuous monitoring of degradation in-situ. The goal was to identify those techniques that appear to be the most promising, i.e., those that are closest to being both technically and commercially viable and that the nuclear industry is most likely to pursue. Current limitations and associated issues that must be overcome before commercial application of certain techniques have also been addressed.

  16. Adaptive coupling between damage mechanics and peridynamics: A route for objective simulation of material degradation up to complete failure

    Science.gov (United States)

    Han, Fei; Lubineau, Gilles; Azdoud, Yan

    2016-09-01

    The objective (mesh-independent) simulation of evolving discontinuities, such as cracks, remains a challenge. Current techniques are highly complex or involve intractable computational costs, making simulations up to complete failure difficult. We propose a framework as a new route toward solving this problem that adaptively couples local-continuum damage mechanics with peridynamics to objectively simulate all the steps that lead to material failure: damage nucleation, crack formation and propagation. Local-continuum damage mechanics successfully describes the degradation related to dispersed microdefects before the formation of a macrocrack. However, when damage localizes, it suffers spurious mesh dependency, making the simulation of macrocracks challenging. On the other hand, the peridynamic theory is promising for the simulation of fractures, as it naturally allows discontinuities in the displacement field. Here, we present a hybrid local-continuum damage/peridynamic model. Local-continuum damage mechanics is used to describe "volume" damage before localization. Once localization is detected at a point, the remaining part of the energy is dissipated through an adaptive peridynamic model capable of the transition to a "surface" degradation, typically a crack. We believe that this framework, which actually mimics the real physical process of crack formation, is the first bridge between continuum damage theories and peridynamics. Two-dimensional numerical examples are used to illustrate that an objective simulation of material failure can be achieved by this method.

  17. Degradation of 1-hydroxy-2,4-dinitrobenzene from aqueous solutions by electrochemical oxidation: role of anodic material.

    Science.gov (United States)

    Quiroz, Marco A; Sánchez-Salas, José L; Reyna, Silvia; Bandala, Erick R; Peralta-Hernández, Juan M; Martínez-Huitle, Carlos A

    2014-03-15

    Electrochemical oxidation (ECOx) of 1-hydroxy-2,4-dinitrobenzene (or 2,4-dinitrophenol: 2,4-DNP) in aqueous solutions by electrolysis under galvanostatic control was studied at Pb/PbO2, Ti/SnO2, Ti/IrxRuySnO2 and Si/BDD anodes as a function of current density applied. Oxidative degradation of 2,4-DNP has clearly shown that electrode material and the current density applied were important parameters to optimize the oxidation process. It was observed that 2,4-DNP was oxidized at few substrates to CO2 with different results, obtaining good removal efficiencies at Pb/PbO2, Ti/SnO2 and Si/BDD anodes. Trends in degradation way depend on the production of hydroxyl radicals (OH) on these anodic materials, as confirmed in this study. Furthermore, HPLC results suggested that two kinds of intermediates were generated, polyhydroxylated intermediates and carboxylic acids. The formation of these polyhydroxylated intermediates seems to be associated with the denitration step and substitution by OH radicals on aromatic rings, this being the first proposed step in the reaction mechanism. These compounds were successively oxidized, followed by the opening of aromatic rings and the formation of a series of carboxylic acids which were at the end oxidized into CO2 and H2O. On the basis of these information, a reaction scheme was proposed for each type of anode used for 2,4-D oxidation.

  18. Adaptive coupling between damage mechanics and peridynamics: a route for objective simulation of material degradation up to complete failure

    KAUST Repository

    Han, Fei

    2016-05-17

    The objective (mesh-independent) simulation of evolving discontinuities, such as cracks, remains a challenge. Current techniques are highly complex or involve intractable computational costs, making simulations up to complete failure difficult. We propose a framework as a new route toward solving this problem that adaptively couples local-continuum damage mechanics with peridynamics to objectively simulate all the steps that lead to material failure: damage nucleation, crack formation and propagation. Local-continuum damage mechanics successfully describes the degradation related to dispersed microdefects before the formation of a macrocrack. However, when damage localizes, it suffers spurious mesh dependency, making the simulation of macrocracks challenging. On the other hand, the peridynamic theory is promising for the simulation of fractures, as it naturally allows discontinuities in the displacement field. Here, we present a hybrid local-continuum damage/peridynamic model. Local-continuum damage mechanics is used to describe “volume” damage before localization. Once localization is detected at a point, the remaining part of the energy is dissipated through an adaptive peridynamic model capable of the transition to a “surface” degradation, typically a crack. We believe that this framework, which actually mimics the real physical process of crack formation, is the first bridge between continuum damage theories and peridynamics. Two-dimensional numerical examples are used to illustrate that an objective simulation of material failure can be achieved by this method.

  19. Objective analysis of properties and material degradation in contact lens polymers using different techniques

    OpenAIRE

    González-Méijome, José Manuel

    2007-01-01

    Tese de Doutoramento em Ciências. Biocompatibility of contact lens polymers is the ability of the material to be worn in direct contact with the ocular surface without an adverse response of the host. In the contact lens field, it depends strongly on the ability of the material to respect the physiological needs of the ocular surface, and avoid or minimize other different forms of interaction. With moderns lenses, many aspects that caused problems in the past (i.e. oxygen trans...

  20. Phenol degradation in an anaerobic fluidized bed reactor packed with low density support materials

    Directory of Open Access Journals (Sweden)

    G. P. Sancinetti

    2012-03-01

    Full Text Available The objective of this research was to study phenol degradation in anaerobic fluidized bed reactors (AFBR packed with polymeric particulate supports (polystyrene - PS, polyethylene terephthalate - PET, and polyvinyl chloride - PVC. The reactors were operated with a hydraulic retention time (HRT of 24 h. The influent phenol concentration in the AFBR varied from 100 to 400 mg L-1, resulting in phenol removal efficiencies of ~100%. The formation of extracellular polymeric substances yielded better results with the PVC particles; however, deformations in these particles proved detrimental to reactor operation. PS was found to be the best support for biomass attachment in an AFBR for phenol removal. The AFBR loaded with PS was operated to analyze the performance and stability for phenol removal at feed concentrations ranging from 50 to 500 mg L-1. The phenol removal efficiency ranged from 90-100%.

  1. Materials and Coatings Damage Resulting from Environmental Degradation Aboard Naval Ships

    Directory of Open Access Journals (Sweden)

    Edward Lemieux

    2005-01-01

    Full Text Available Maintenance and preservation of seawater and fuel, ballast tanks and voids resulting from the environmental degradation of coatings present a unique and costly problem for the United States Naval Fleet. Present methods of inspection require human entry into the tanks only after a series of measurements have been taken to ensure safety. With the advent of remotely operated vehicles and cameras having a high level of accuracy and functionality, it has now become economically feasible to employ these instruments for the inspection of tanks and voids of the United States Naval Fleet. This paper presents two unique remotely operated inspections systems, which allow for unmanned inspection of tanks and voids along with quantitative results of the damaged coating areas.

  2. An overview of environmental degradation of materials in nuclear power plant piping systems

    Energy Technology Data Exchange (ETDEWEB)

    Shack, W.J.

    1987-08-01

    Piping in light water reactor (LWR) power systems is affected by several types of environmental degradation: intergranular stress corrosion cracking (IGSCC) of austenitic stainless steel piping in boiling water reactors (BWRs) has required research, inspection, and mitigation programs that will ultimately cost several billion dollars; erosion-corrosion of carbon steel piping has been observed frequently in the secondary systems of both BWRs and pressurized water reactors (PWRs); the effect of the BWR environment can greatly diminish the design margin inherent in the ASME Section III fatigue design curves for carbon steel piping; and cast stainless steels are subject to embrittlement after extended thermal aging at reactor operating temperatures. These problems are being addressed by wide-ranging research programs in this country and abroad. The purpose of this review is to highlight some of the accomplishments of these programs and to note some of the remaining unanswered questions.

  3. Bricolage as Institutional Maintenance Work: integrating new construction materials into heritage buildings

    OpenAIRE

    Colombero, Sylvain

    2014-01-01

    International audience; Listed-buildings refers to buildings that are protected by the state because of their recognized status as national patrimony. Many listed buildings are currently undergoing various construction works, such as renovation or extension, to preserve them while keeping intact the function for which they were originally built. Increased use of construction practices pertaining to Sustainable Development is calling for insight into the process through which these kinds of bu...

  4. An application of luminiscence dating to building archaeology: The study of ceramic building materials in early medieval churches in north-western France and south-eastern England

    Directory of Open Access Journals (Sweden)

    Blain, Sophie

    2010-12-01

    Full Text Available The research reported in this thesis concerns the re-evaluation of an archaeological assumption surrounding the origin of Ceramic Building Materials (CBM used from the 9th to the 11th century in religious buildings of north-western France and south-eastern England. Are the bricks used in the masonry structures Roman spolia or a novo productions? Amongst the dating methods that can contribute to building archaeology, it is the technique of stimulated luminescence applied to CBM that is the focus of this study. Results from thermoluminescence (TL and optically stimulated luminescence (OSL dating performed on 52 CBM samples from 11 churches showed that the practice of reusing Roman brick was commonplace in small parish churches, but also that brick-making was not a totally unknown skill of the early medieval craftsmen as it has long been supposed. Most importantly, by identifying that the building material is contemporary to the church, a defined chronology emerges resulting in a new and extremely useful reference point in the history of early medieval architecture.La investigación presentada en esta tesis se ocupa de la reevaluación de un supuesto arqueológico entorno al origen del material cerámico constructivo (CBM empleado entre los siglos IX y XI en los edificios religiosos del Noroeste de Francia y el Sudeste de Inglaterra. ¿Son los ladrillos empleados en las estructuras de fábrica spolia romana o producciones a novo? Entre los métodos de datación que pueden contribuir a la arqueología del edificio, la técnica de luminiscencia estimulada aplicada al CBM es el centro de este estudio. Los resultados de la termoluminiscencia (TL y de la luminiscencia estimulada ópticamente (OSL, aplicadas en 52 muestras de CBM tomadas en 11 iglesias, evidencian que la práctica de reutilizar ladrillos romanos era común en pequeñas iglesias parroquiales, pero que también la técnica de elaboración de ladrillos no era totalmente desconocida para los

  5. Survey of degradation modes of candidate materials for high-level radioactive-waste disposal containers

    Energy Technology Data Exchange (ETDEWEB)

    Gdowski, G.E.; Bullen, D.B. (Science and Engineering Associates, Inc., Pleasanton, CA (USA))

    1988-08-01

    Three copper-based alloys and three iron- to nickel-based austenitic alloys are being considered as possible materials for fabrication of containers for disposal of high-level radioactive waste. This waste will include spent fuel assemblies from reactors as well as high-level waste in borosilicate glass and will be sent to the prospective site at Yucca Mountain, Nevada, for disposal. The containers must maintain substantially complete containment for at least 300 yr and perhaps as long as 1000 yr. During the first 50 yr after emplacement, they must be retrievable from the disposal site. Shortly after the containers are emplaced in the repository, they will be exposed to high temperatures and high gamma radiation fields from the decay of the high-level waste. This volume surveys the available data on oxidation and corrosion of the iron- to nickel-based austenitic materials (Types 304L and 316L stainless steels and Alloy 825) and the copper-based alloy materials (CDA 102 (oxygen-free copper), CDA 613 (Cu-7Al), and CDA 715 (Cu-30Ni)), which are the present candidates for fabrication of the containers. Studies that provided a large amount of data are highlighted, and those areas in which little data exists are identified. Examples of successful applications of these materials are given. On the basis of resistance to oxidation and general corrosion, the austenitic materials are ranked as follows: Alloy 825 (best), Type 316L stainless steel, and then Type 304L stainless steel (worst). For the copper-based materials, the ranking is as follows: CDA 715 and CDA 613 (both best), and CDA 102 (worst). 110 refs., 30 figs., 13 tabs.

  6. Data on comparison between FLEC and CLIMPAQ methods used for fast sorption measurements of VOCs on building materials

    Directory of Open Access Journals (Sweden)

    Malak Rizk

    2016-06-01

    Full Text Available A test emission chamber called CLIMPAQ has been coupled to a chromatography analyzer GC to measure volatile organic compounds (VOC concentration during a sorption experiments (Fast sorption measurements of VOCs on building materials: Part 2 – Comparison between FLEC and CLIMPAQ methods, (Rizk et al., In press [1]. The equations used to calculate the mass transfer coefficient and the thickness of the boundary layer developed on the surface of a material are presented. In addition, the experimental profiles obtained using the CLIMPAQ chamber is also presented in the presence and the absence of a building material. Finally, the impact of chamber size on the obtained concentration profile using different chambers is shown using 3 types of chambers having different volumes, 1 m3, 30 m3 and a micro chamber of 40 mL.

  7. Application of smart materials in buildings%探析智能材料在建筑中的应用

    Institute of Scientific and Technical Information of China (English)

    张阿玲

    2014-01-01

    This paper first introduces the overview of intelligent material and intelligent material status, and then introduced the analyses the application of smart materials in the building from four aspects.%本文首先介绍了关于智能材料的概述以及智能材料的现状,接下来介绍了从四个方面对智能材料在建筑中的应用进行了探析。

  8. Optimization model for the selection of materials using a LEED-based green building rating system in Colombia

    Energy Technology Data Exchange (ETDEWEB)

    Castro-Lacouture, Daniel [Building Construction Program, College of Architecture, Georgia Institute of Technology, 280 Ferst Drive, Atlanta, GA 30332 (United States); Sefair, Jorge A.; Florez, Laura; Medaglia, Andres L. [Centro de Optimizacion y Probabilidad Aplicada (COPA), Departamento de Ingenieria Industrial, Universidad de los Andes, Bogota D.C. (Colombia)

    2009-06-15

    Buildings have a significant and continuously increasing impact on the environment because they are responsible for a large portion of carbon emissions and use a considerable number of resources and energy. The green building movement emerged to mitigate these effects and to improve the building construction process. This paradigm shift should bring significant environmental, economic, financial, and social benefits. However, to realize such benefits, efforts are required not only in the selection of appropriate technologies but also in the choice of proper materials. Selecting inappropriate materials can be expensive, but more importantly, it may preclude the achievement of the desired environmental goals. In order to help decision-makers with the selection of the right materials, this study proposes a mixed integer optimization model that incorporates design and budget constraints while maximizing the number of credits reached under the Leadership in Energy and Environmental Design (LEED) rating system. To illustrate this model, this paper presents a case study of a building in Colombia in which a modified version of LEED is proposed. (author)

  9. Integration of Phase Change Material in Furniture for Improvement of Building Energy Flexibility

    DEFF Research Database (Denmark)

    Johra, Hicham; Heiselberg, Per

    This report aims to review the different scientific publications and technical documentations which investigated the influence of furniture parts on indoor environment and the use of PCM for building energy applications.......This report aims to review the different scientific publications and technical documentations which investigated the influence of furniture parts on indoor environment and the use of PCM for building energy applications....

  10. Assessment of Natural Radioactivity Levels and Potential Radiological Risks of Common Building Materials Used in Bangladeshi Dwellings.

    Directory of Open Access Journals (Sweden)

    Khandoker Asaduzzaman

    Full Text Available The concentrations of primordial radionuclides (226Ra, 232Th and 40K in commonly used building materials (brick, cement and sand, the raw materials of cement and the by-products of coal-fired power plants (fly ash collected from various manufacturers and suppliers in Bangladesh were determined via gamma-ray spectrometry using an HPGe detector. The results showed that the mean concentrations of 226Ra, 232Th and 40K in all studied samples slightly exceeded the typical world average values of 50 Bq kg(-1, 50 Bq kg(-1 and 500 Bq kg(-1, respectively. The activity concentrations (especially 226Ra of fly-ash-containing cement in this study were found to be higher than those of fly-ash-free cement. To evaluate the potential radiological risk to individuals associated with these building materials, various radiological hazard indicators were calculated. The radium equivalent activity values for all samples were found to be lower than the recommended limit for building materials of 370 Bq kg(-1, with the exception of the fly ash. For most samples, the values of the alpha index and the radiological hazard (external and internal indices were found to be within the safe limit of 1. The mean indoor absorbed dose rate was observed to be higher than the population-weighted world average of 84 nGy h(-1, and the corresponding annual effective dose for most samples fell below the recommended upper dose limit of 1 mSv y(-1. For all investigated materials, the values of the gamma index were found to be greater than 0.5 but less than 1, indicating that the gamma dose contribution from the studied building materials exceeds the exemption dose criterion of 0.3 mSv y(-1 but complies with the upper dose principle of 1 mSv y(-1.

  11. Assessment of Natural Radioactivity Levels and Potential Radiological Risks of Common Building Materials Used in Bangladeshi Dwellings.

    Science.gov (United States)

    Asaduzzaman, Khandoker; Mannan, Farhana; Khandaker, Mayeen Uddin; Farook, Mohideen Salihu; Elkezza, Aeman; Amin, Yusoff Bin Mohd; Sharma, Sailesh; Abu Kassim, Hasan Bin

    2015-01-01

    The concentrations of primordial radionuclides (226Ra, 232Th and 40K) in commonly used building materials (brick, cement and sand), the raw materials of cement and the by-products of coal-fired power plants (fly ash) collected from various manufacturers and suppliers in Bangladesh were determined via gamma-ray spectrometry using an HPGe detector. The results showed that the mean concentrations of 226Ra, 232Th and 40K in all studied samples slightly exceeded the typical world average values of 50 Bq kg(-1), 50 Bq kg(-1) and 500 Bq kg(-1), respectively. The activity concentrations (especially 226Ra) of fly-ash-containing cement in this study were found to be higher than those of fly-ash-free cement. To evaluate the potential radiological risk to individuals associated with these building materials, various radiological hazard indicators were calculated. The radium equivalent activity values for all samples were found to be lower than the recommended limit for building materials of 370 Bq kg(-1), with the exception of the fly ash. For most samples, the values of the alpha index and the radiological hazard (external and internal) indices were found to be within the safe limit of 1. The mean indoor absorbed dose rate was observed to be higher than the population-weighted world average of 84 nGy h(-1), and the corresponding annual effective dose for most samples fell below the recommended upper dose limit of 1 mSv y(-1). For all investigated materials, the values of the gamma index were found to be greater than 0.5 but less than 1, indicating that the gamma dose contribution from the studied building materials exceeds the exemption dose criterion of 0.3 mSv y(-1) but complies with the upper dose principle of 1 mSv y(-1).

  12. Real-Time Characterization of Materials Degradation Using Leaky Lamb Wave

    Science.gov (United States)

    Shiuh, S.; Bar-Cohen, Y.

    1997-01-01

    Leaky Lamb wave (LLW) propagation in composite materials has been studied extensively since it was first observed in 1982. The wave is induced using a pitch-catch arrangement and the plate wave modes are detected by searching minima in the reflected spectra.

  13. TRUE COLORS: LEDS AND THE RELATIONSHIP BETWEEN CCT, CRI, OPTICAL SAFETY, MATERIAL DEGRADATION, AND PHOTOBIOLOGICAL STIMULATION

    Energy Technology Data Exchange (ETDEWEB)

    Royer, Michael P.

    2014-08-30

    This document analyzes the optical, material, and photobiological hazards of LED light sources compared to conventional light sources. It documents that LEDs generally produce the same amount of blue light, which is the primary contributor to the risks, as other sources at the same CCT. Duv may have some effect on the amount of blue light, but CRI does not.

  14. Nanoenhanced Materials for Reclamation of Mine Lands and Other Degraded Soils: A Review

    Directory of Open Access Journals (Sweden)

    Ruiqiang Liu

    2012-01-01

    Full Text Available Successful mine soil reclamation facilitates ecosystem recovery, minimizes adverse environmental impacts, creates additional lands for agricultural or forestry uses, and enhances the carbon (C sequestration. Nanoparticles with extremely high reactivity and deliverability can be applied as amendments to improve soil quality, mitigate soil contaminations, ensure safe land–application of the conventional amendment materials (e.g., manures and biosolids, and enhance soil erosion control. However, there is no report on using nanoenhanced materials for mine soil reclamation. Through reviewing the up-to-date research results on using environment-friendly nanoparticles for agricultural soil quality improvement and for contaminated soil remediation, this paper synthesizes that these nanomaterials with high potentials for mine soil reclamation include zeolites, zero-valent iron nanoparticles, iron oxide nanoparticles, phosphate-based nanoparticles, iron sulfide nanoparticles and C nanotubes. Transport of these particles in the environment and their possible ecotoxicological effects are also discussed. Additionally, this article proposes a practical and economical approach to applying nanotechnology for mine soil reclamation: adding small amounts of nanoparticles to the conventional soil amendment materials and then applying the mixtures for soil quality improvements. Hence the cost of using nanoparticles is reduced and the benefits of both nanoparticles and the conventional amendment materials are harnessed.

  15. Degraded areas of organised multi-apartment building between 1945 and 1965 in Slovenia – methodology of evaluation and rehabilitation

    Directory of Open Access Journals (Sweden)

    Tadeja Zupančič Strojan

    2002-01-01

    Full Text Available “Degraded” housing areas represent a 9% share of urbanised surfaces of thirty-five in planning terms recently researched Slovenian towns. Above all social housing estates built between 1945 and 1965 present issues since they are isolated, poorly maintained, and cannot reach modern standards. The research contemplates the redirecting of the present abstract planning rationales to the real architectural, user level. Further intentions of the research are to consolidate ideas about the urgency of renewal as the only possible method of solving problems of a certain pattern of building, to determine criteria and measures for renewal and to determine rational or real directions for concrete contributions for the improvement of the standard of living, in short, to a new shift in living culture discussed settlement pattern.

  16. Nuclear industry practice for clearance of materials, facilities and buildings as well as land. Tutorial; Kaerntekniska industrins praxis foer friklassning av material, lokaler och byggnader samt mark. Handledning

    Energy Technology Data Exchange (ETDEWEB)

    2011-12-15

    This handbook comprises the common practices of the Swedish nuclear industry for the clearance of material, rooms, buildings and soil in order to be exempted from the Swedish Nuclear Activities Act and the Swedish Radiation Protection Act. After clearance the management/usage of material, rooms, buildings and soil is permitted without any control from the radiation protection point of view. Clearance is practiced to reduce the amount radioactive waste. Cleared material can be reused according to its original form, recycled or, if these two possibilities are not available, disposed as conventional waste. The working procedures described in this handbook are mainly based on the regulation SSMFS 2011:2 from the Swedish Radiation Safety Authority: 'Regulations concerning clearance of material, rooms, buildings and soil from activities with ionising radiation'. The purpose of this handbook is to serve as a tool and guidance for generating specific routines and instructions for clearance. It describes the principles, processes and routines that should be followed under a clearance procedure. The intention is to accomplish the current regulation by following the routines and principles described in this manual. This handbook spans over a large number of conditions towards clearance, such as facility specific conditions and different types of objects. Because not all the conceivable conditions and objects can be included here, the purpose has been to cover the most common types of clearance practices. The practices comprise: - Description of regulations and recommendations, Swedish and international, that represent the basis of the requirements in this handbook. - Presentation of the processes for clearance of material, rooms, buildings and soil. Those which cannot be cleared are considered as radioactive waste. A proposal for the decision-making process is presented. - Illustration for radiological surveys to systems and components, buildings and soil in regard

  17. Thermogravimetric Determination of Kinetic Parameters for the Thermal Degradation of Several Ablative Materials.

    Science.gov (United States)

    1980-12-01

    Materials by a Multiple Heating Rate Method, " Thermochimica Acta , in press, and also NSWC TR 80-204 (Dahlgren, Va., July 1980). 3. J. H. Flynn and L. A...System," Thermochimica Acta , No. 1, (1970), pp. 29-38. 21 APPENDIX EXPERIMENTAL DATA 23 4-l *~0 0 0 0 8 a 1 0 0 0 0 0 N 0 0 S 3- 0 0 0 0 0 0 0 0 0 0

  18. Survey of the degradation modes of candidate materials for high-level radioactive waste disposal containers

    Energy Technology Data Exchange (ETDEWEB)

    Vinson, D.W.; Nutt, W.M.; Bullen, D.B. [Iowa State Univ. of Science and Technology, Ames, IA (United States)

    1995-06-01

    Oxidation and atmospheric corrosion data suggest that addition of Cr provides the greatest improvement in oxidation resistance. Cr-bearing cast irons are resistant to chloride environments and solutions containing strongly oxidizing constituents. Weathering steels, including high content and at least 0.04% Cu, appear to provide adequate resistance to oxidation under temperate conditions. However, data from long-term, high-temperature oxidation studies on weathering steels were not available. From the literature, it appears that the low alloy steels, plain carbon steels, cast steels, and cast irons con-ode at similar rates in an aqueous environment. Alloys containing more than 12% Cr or 36% Ni corrode at a lower rate than plain carbon steels, but pitting may be worse. Short term tests indicate that an alloy of 9Cr-1Mo may result in increased corrosion resistance, however long term data are not available. Austenitic cast irons show the best corrosion resistance. A ranking of total corrosion performance of the materials from most corrosion resistant to least corrosion resistant is: Austenitic Cast Iron; 12% Cr = 36% Ni = 9Cr-1Mo; Carbon Steel = Low Alloy Steels; and Cast Iron. Since the materials to be employed in the Advanced Conceptual Design (ACD) waste package are considered to be corrosion allowance materials, the austenitic cast irons, high Cr steels, high Ni steels and the high Cr-Mo steels should not be considered as candidates for the outer containment barrier. Based upon the oxidation and corrosion data available for carbon steels, low alloy steels, and cast irons, a suitable list of candidate materials for a corrosion allowance outer barrier for an ACD waste package could include, A516, 2.25%Cr -- 1%Mo Steel, and A27.

  19. Understanding of Materials State and its Degradation using Non-Linear Ultrasound (NLU) Approaches

    Science.gov (United States)

    2011-07-01

    at Ultrasonic Frequencies, Journal of Applied Physics 105, 043520, Hikata A., Chick B. B., and Elbaum C., (1965) Dislocation Contribution to the...Second Harmonic Generation of ultrasonic waves, Journal of Applied Physics Vol. 36 Number1 Hikata A. and Elbaum C., (1966) Generation of...Material Damage in a Nickel-base Superalloy using Nonlinear Rayleigh Surface Waves, Journal of Applied Physics 99, 124913 Hurley D. C., Balzar D

  20. Optical response of strongly absorbing inhomogeneous materials: Application to paper degradation

    Science.gov (United States)

    Missori, M.; Pulci, O.; Teodonio, L.; Violante, C.; Kupchak, I.; Bagniuk, J.; Łojewska, J.; Conte, A. Mosca

    2014-02-01

    In this paper, we present a new noninvasive and nondestructive approach to recover scattering and absorption coefficients from reflectance measurements of highly absorbing and optically inhomogeneous media. Our approach is based on the Yang and Miklavcic theoretical model of light propagation through turbid media, which is a generalization of the Kubelka-Munk theory, extended to accommodate optically thick samples. We show its applications to paper, a material primarily composed of a web of fibers of cellulose, whose optical properties are strongly governed by light scattering effects. Samples studied were ancient and industrial paper sheets, aged in different conditions and highly absorbing in the ultraviolet region. The recovered experimental absorptions of cellulose fibers have been compared to theoretical ab initio quantum-mechanical computational simulations carried out within time-dependent density functional theory. In this way, for each sample, we evaluate the absolute concentration of different kinds of oxidized groups formed upon aging and acting as chromophores causing paper discoloration. We found that the relative concentration of different chromophores in cellulose fibers depends on the aging temperature endured by samples. This clearly indicates that the oxidation of cellulose follows temperature-dependent reaction pathways. Our approach has a wide range of applications for cellulose-based materials, like paper, textiles, and other manufactured products of great industrial and cultural interest, and can potentially be extended to other strongly absorbing inhomogeneous materials.