WorldWideScience

Sample records for building materials degradation

  1. Gas chromatographic study of degradation phenomena concerning building and cultural heritage materials

    International Nuclear Information System (INIS)

    Air pollution influences all aspects of social and economical life nowadays. In order to investigate the impact of air pollution on materials of works of art, the method of Reversed Flow-Inverse Gas Chromatography has been selected. The presence of various atmospheric pollutants is studied on marbles, oxides-building materials and samples of authentic statues from the Greek Archaeological Museums of Kavala and of Philippi. The method leads to the determination of several physicochemical quantities and the characterization of the heterogeneous surfaces of these solids. Moreover, the influence of a second pollutant (synergistic effect) is examined. The structure, the properties and the behavior of the materials are examined by X-Ray Diffraction, Scanning Electron Microscopy and Raman Spectroscopy. Therefore, the precise measurement of the above mentioned quantities form the scientific basis for elucidation of the mechanism of the whole phenomenon of the degradation, thus providing a scientific platform to conservation procedures.

  2. Degradation of building materials over a lifespan of 30-100 years

    International Nuclear Information System (INIS)

    Following preliminary visits to four Magnox Nuclear Power Stations, a study was made of existing Central Electricity Generating Board (CEGB) reports on the condition of buildings at eight Power Stations. Sampling of building materials, non-destructive testing and inspections were carried out at Transfynydd, Oldbury and Dungeness ''A'' Magnox Power Stations, and the samples were subsequently laboratory tested. From the results of this work it can be concluded that little major deterioration is likely to occur in the reactor buildings at Transfynydd and Oldbury over the next 50 years and at Dungeness ''A'' for at least 25 years, assuming reasonable maintenance and the continuation of suitable internal temperatures and relative humidities. Because of the limitations on taking samples from, and tests on, the reactor biological shields and prestressed concrete vessel, no sensible forecast can be made of their potential life in the 75-100 year range

  3. Material degradation - a nuclear utility's view

    International Nuclear Information System (INIS)

    Degradation of nuclear plant materials has been responsible for major costs and unit outage time. As such, nuclear utilities are important end users of the information produced by R and D on material degradation. This plenary describes the significance of material degradation for the nuclear utilities, and how utilities use information about material degradation in their short, medium and long term planning activities. Utilities invest in R and D programs to assist them in their business objective of operating safely, reliably and cost competitively. Material degradation impacts all three of these business drivers. Utilities make decisions on life cycle planning, unit refurbishment and 'new build' projects on the basis of their understanding of the behaviour of a variety of materials in a broad range of environments. The R and D being carried out today will determine the future business success of the nuclear utilities. The R and D program needs to be broadly based to include a range of materials, environments and time-frames, particularly any new materials proposed for use in new units. The R and D community needs to help the utility managers make choices that will result in an optimized materials R and D program

  4. Radioactivity in building materials

    International Nuclear Information System (INIS)

    The present report, drawn up at the request of the former Minister of Public Health and Environmental Affairs of the Netherlands, discusses the potential radiological consequences for the population of the Netherlands of using waste materials as building materials in housing construction. (Auth.)

  5. 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....

  6. 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 as a...

  7. 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.

  8. Building Materials Reclamation Program

    International Nuclear Information System (INIS)

    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 and 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 and 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 and D materials. Table 1 summarizes the six subprojects, including the C and D material studied and the graduate student and the faculty advisor on each subproject.

  9. Radiation exposure from building materials

    International Nuclear Information System (INIS)

    A survey procedure was developed to find buildings in which the radiation exposure from gamma rays is relatively high. For modern structures NaI(Tl) survey meters are used to identify building materials with higher radionuclide content. Samples of these materials are analyzed by gamma-ray spectroscopy for 226Ra daughters, 232Th daughters, and 40K. The exposure rate in a building is computed from these concentrations on the basis of the geometrical configuration of building materials, acting both as radiation sources and as a shield against terrestrial radiation, and also on the basis of the outside radiation exposure rate at the building site. The procedure may also be applied to surveys of building material constituents and to materials in place in older structures. A calculational model was developed to predict radiation exposure rates within the houses

  10. 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.

  11. Mould growth on building materials

    DEFF Research Database (Denmark)

    Fog Nielsen, K.

    Mould growth in buildings is associated with adverse health effects among the occupants of the building. However actual growth only occurs in damp and water-damaged materials, and is an increasing problem in Denmark, due to less robust constructions, inadequate maintenance, and too little...... ventilation. This project was started to determine if mycotoxins are produced in damp and water-damaged buildings as well investigating the influence of environmental conditions (humidity and temperature) on the production of fungal growth and secondary metabolism....

  12. Radioactive research of building material

    International Nuclear Information System (INIS)

    Radionuclides in 31 pieces of ground bricks from different sources were determined by using the γ spectrometry. The spectra were resolved by the least square method. The contents of U, Th, Ra and 40K in them spread in a wide range. Values of some bricks products were above the limits of the state standard for radiahazards in building materials

  13. Radioactive substances in building materials

    International Nuclear Information System (INIS)

    The report reviews all activity measurements performed on building materials at SSI during 1962 and 1972-1984. The content of 232-Th, 226-Ra and 40-K was determined. The measuring method and the accuracy is discussed. Comparisons are made to measurements from the 1950:s. (L.E.)

  14. Radon exhalation from building materials

    International Nuclear Information System (INIS)

    The new Israeli standard 5098 limits the total radiation dose of the general public from building materials to 0.45 mSv / year. A building material is accepted if it satisfies a criterion depending on the activity concentration of the natural radionuclides 226Ra, 232Th, 40K and on the Radon (222Rn) exhalation rate. As compared with existing standards, which consider only the gamma dose, this standard includes the Radon contribution allowing thereby to rigorously control the radiation dose from this practice to the general public in Israel. While the radionuclide activity may be measured via standard HPGe gamma spectroscopy, the measurement of the Radon exhalation rate is not yet standardized. According to Standard 5098 the Ministry of the Environment is responsible to recommend the optimal technique

  15. 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...... critical degrees of saturation are compared with experimentally determined values and results from standardised freeze-thaw tests. Based on these results, the model, its mode of operation and the conditions of the model is analysed and discussed.Appendices and description of supplementary tests are placed...

  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. 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

  18. 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.

  19. Radioactive substances in the Danish building materials

    International Nuclear Information System (INIS)

    Building materials as any other materials of natural occurrence contain small concentrations of natural radioactive elements. This natural radioactivity affects people inside buildings. This publiccation refers measurements of the Danish building materials, and radiation doses originating from this source affecting the Danish population are related to the other components of background radioactivity. (EG)

  20. Building materials cooperatives in New England

    OpenAIRE

    Kathleen Gill

    2000-01-01

    Low- and moderate-income (LMI) homeowners in New England often find it difficult to repair their homes due to the high cost of building materials. Kathleen Gill highlights how the emerging building materials cooperatives work to offer LMI homeowners discounted building materials, appliances, and supplies, while also keeping unwanted construction products from clogging up landfills.

  1. Degradation of automotive materials in palm biodiesel

    International Nuclear Information System (INIS)

    As compared to petroleum diesel, biodiesel is more corrosive for automotive materials. Studies on the characterization of corrosion products of fuel exposed automotive materials are scarce. Automotive fuel system and engine components are made from different ferrous and non-ferrous materials. The present study aims to investigate the corrosion products of different types of automotive materials such as copper, brass, aluminum and cast iron upon exposure to diesel and palm biodiesel. Changes in fuel properties due to exposure of different materials were also examined. Degradation of metal surface was characterized by digital camera, SEM/EDS and X-ray diffraction (XRD). Fuel properties were examined by measuring TAN (total acid number), density and viscosity. Among the metal investigated, copper is found to be least resistant in biodiesel and formed comparatively more corrosion products than other metals. Upon exposure of metals in biodiesel, TAN number crosses the limit given by standard while density and viscosity remain within the acceptable range of limit. -- Highlights: ► Order of incompatible metals in palm biodiesel: copper > brass > aluminum > cast iron. ► The possible reactions for the degradation of copper and cast iron have been discussed. ► For metal exposed biodiesel, only TAN number crosses the limit while density and viscosity remain within the limit. ► Copper and copper based alloy (brass) increase TAN number comparatively more than other metals.

  2. Environmental Evaluation of Building Materials of 5 Slovak Buildings

    Science.gov (United States)

    Porhincak, Milan; Estokova, Adriana

    2013-11-01

    Building activity has recently led to the deterioration of environment and has become unsustainable. Several strategies have been introduced in order to minimize consumption of energy and resulting CO2 emissions having their origin in the operational phase. But also other stages of Life Cycle should are important to identify the overall environmental impact of construction sector. In this paper 5 similar Slovak buildings (family houses) were analyzed in terms of environmental performance of building materials used for their structures. Evaluation included the weight of used materials, embodied energy and embodied CO2 and SO2 emissions. Analysis has proven that the selection of building materials is an important factor which influences the environmental profile. Findings of the case study indicated that materials like concrete, ceramic or thermal insulation materials based on polystyrene and mineral wool are ones with the most negative environmental impact.

  3. Environmental radiation of different building materials

    International Nuclear Information System (INIS)

    The influences of some parameters on the doserate inside and in the environment of buildings are discussed and calculations of the gammaray exposure from walls of different materials are reported. Results of dose measurements are given and it can be shown, that the used building material has an important influence on the natural radiation dose. Dose rates inside concrete buildings are sometimes lower than those outside; in dwellings with walls of brick we found significant higher doses that outside. (Author)

  4. 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...

  5. (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.

  6. Mechanical degradation temperature of waste storage materials

    International Nuclear Information System (INIS)

    Heat loading analysis of the Solid Waste Disposal Facility (SWDF) waste storage configurations show the containers may exceed 90 degrees C without any radioactive decay heat contribution. Contamination containment is primarily controlled in TRU waste packaging by using multiple bag layers of polyvinyl chloride and polyethylene. Since literature values indicate that these thermoplastic materials can begin mechanical degradation at 66 degrees C, there was concern that the containment layers could be breached by heating. To better define the mechanical degradation temperature limits for the materials, a series of heating tests were conducted over a fifteen and thirty minute time interval. Samples of a low-density polyethylene (LDPE) bag, a high-density polyethylene (HDPE) high efficiency particulate air filter (HEPA) container, PVC bag and sealing tape were heated in a convection oven to temperatures ranging from 90 to 185 degrees C. The following temperature limits are recommended for each of the tested materials: (1) low-density polyethylene -- 110 degrees C; (2) polyvinyl chloride -- 130 degrees C; (3) high-density polyethylene -- 140 degrees C; (4) sealing tape -- 140 degrees C. Testing with LDPE and PVC at temperatures ranging from 110 to 130 degrees C for 60 and 120 minutes also showed no observable differences between the samples exposed at 15 and 30 minute intervals. Although these observed temperature limits differ from the literature values, the trend of HDPE having a higher temperature than LDPE is consistent with the reference literature. Experimental observations indicate that the HDPE softens at elevated temperatures, but will retain its shape upon cooling. In SWDF storage practices, this might indicate some distortion of the waste container, but catastrophic failure of the liner due to elevated temperatures (<185 degrees C) is not anticipated

  7. Radiation and thermal degradation on polymer materials

    International Nuclear Information System (INIS)

    In this work we have studied the degradation and damaging effects induced by radiation and by temperature on AFUMEXR, an insulation for electrical cables produced and marketed by Pirelli Cable Society and on a cable coming from a decommissioned Italian nuclear plant. As it regards AFUMEXR we obtained the following results. 1) Three thermal aging curves were obtained and an activation energy of 1.23 eV was found. Radiation damage was evaluated by measuring the decrease in the elastic properties and was found greater when thermal ageing followed radiation. 2) Mainly hydrogen and carbon dioxide were evolved by the samples subjected to radiation and their quantity increased with the absorbed dose. 3) Radiation seemed to produce no effect on the oxygen index values. 4) Thermogravimetric tests for samples either thermally aged and then irradiated or just irradiated showed that significant oxidation phenomena were produced. 5) The ESR technique has been used to investigate the behaviour of irradiation induced free-radicals in different environmental conditions; the signal was unaffected till a dose value of 10 KGy beyond which increased as a function of the absorbed dose. The signal increased 47% for samples irradiated in vacuum and 59% for those in air: time dependance of the signal showed a marked fading for the former and an increase for the latter. This suggests the presence of oxidative degradation processes in the material. 6) Two different materials based on EPR (30% and 50% propylene respectively) did not exhibit any difference as for their radiation resistance either in air or in argon. As it concerns the cables coming from a decommissioned Italian nuclear plant we have not found significant differences in tensile properties between cables stocked in the storehouse and those which had been in use. Insulation constant and partial discharges indicated a slight ageing of the latter. (author). 9 refs, 12 figs, 2 tabs

  8. 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...

  9. Natural radioactivity in building materials at Kalpakkam

    International Nuclear Information System (INIS)

    The need for determination of natural radioactivity content in building materials arises from the growing attention paid to its potential radiation effects and consequent concern of many producers of such materials These materials have been analyzed for natural radioactivity due to presence of primordial radionuclide 238U, 232Th and 40K using gamma spectrometry. The activity of different building material obtained in this study ranged from 1-72 Bq/kg for 226Ra, 4-148 Bq/kg for 232Th and 38-1288 for 40K respectively. The radium equivalent activity (Raeq) values of all the building materials are lower than the limit of 370 Bq/kg which will produce an exposure of 1.5 mSv/yr to the inhabitants. In all cases both External hazard index Hex and Internal hazard index Hin in all the building materials collected and analysed in this paper is below unity. Based on the criterion formula for gamma activity the results presented indicate that the commonly used building materials in Kalpakkam could be used in building construction without exceeding the proposed radioactivity criterion level. (author)

  10. 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

  11. Moisture Buffer Value of Building Materials

    OpenAIRE

    Rode, C.; Peuhkuri, R.; Hansen, K. K.; Time, B.; Svennberg, Kaisa; Arfvidsson, Jesper; Ojanen, T.

    2006-01-01

    Building materials and furnishing used in contact with indoor air may have a positive effect to moderate the variations of indoor humidity seen in occupied buildings. Thus, very low humidity can be alleviated in winter, as well as can high indoor humidity in summer and during high occupancy loads. This way, materials can be used as a passive means of establishing indoor climatic conditions, which are comfortable for human occupancy, or for safe storing of artefacts which are sensible to humid...

  12. Drying kinetics of some building materials

    OpenAIRE

    Moropoulou, A.; M Karoglou; Giakoumaki, A.; Krokida, M. K.; Maroulis, Z. B.; G.D. Saravacos

    2005-01-01

    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 ...

  13. New build: Materials, techniques, skills and innovation

    International Nuclear Information System (INIS)

    The transition to secure, sustainable, low-energy systems will have a significant effect on the way in which we design and construct new buildings. In turn, the new buildings that are constructed will play a critical role in delivering the better performance that would be expected from such a transition. Buildings account for about half of UK carbon dioxide (CO2) production. So it is urgent to ensure that energy is used efficiently in existing buildings and that new building stock is better able to cope with whatever the future holds. Most energy used in buildings goes towards heating, lighting and cooling, but a growing percentage is consumed by domestic appliances, computers and other electrical equipment. Actual energy consumption is the product of a number of factors, including individual behaviours and expectations, the energy efficiency of appliances and the building envelope. This review focuses on the third of these, the building itself, and its design and construction. It discusses the issues faced by the construction industry today, suggesting that major changes are needed relating to materials, techniques, skills and innovation. It moves on to consider future advances to 2050 and beyond, including developments in ICT, novel materials, skills and automation, servitisation (the trend for manufacturers to offer lifetime services rather than simple products), performance measurement and reporting, and resilience. We present a vision of the new build construction industry in 2050 and recommendations for policy makers, industry organisations and construction companies

  14. 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.

  15. 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 of...... a recent Nordic project to define such a quantity, and to declare it in the form of a NORDTEST method. The Moisture Buffer Value is the figure that has been developed in the project as a way to appraise the moisture buffer effect of materials, and the value is described in the paper. Also explained...... 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....

  16. Ageing degradation in the Gentilly-1 concrete containment building

    International Nuclear Information System (INIS)

    Concrete containment buildings (CCBs) are designed for a service life up to 40 years, but nuclear power plant (NPP) refurbishment can extend service life beyond 60 years. Only limited testing can be conducted on an in-service CCB. The Gentilly-1 (G-1) NPP is in a safe, sustainable shutdown state and the G-1 CCB was available for testing to determine age-related degradation that may be relevant to operating CCBs. Visual observation of the G-1 CCB helped to identify various signs of degradation. However, field testing, via concrete removal, was performed to: (i) examine reinforcing bars and concrete to determine their condition and in-situ stresses and (ii) examine condition of post-tensioned (P-T) wires. The concrete was also subjected to laboratory tests to evaluate its physical, mechanical and chemical properties such as compressive strength, carbonation depth, chloride content and presence of internal degradation. The degradation mechanisms that were clearly visible include macro- and micro-cracking, efflorescence, and weathering. The reinforcing bars in the perimeter wall and dome exposed during the program showed no evidence of active corrosion. Corrosion products were observed on the surfaces of most exposed P-T wires in the perimeter wall, but none were present on P-T wires exposed in the dome. Laboratory testing on the concrete cores extracted from the CCB revealed compressive strength in excess of the design requirements, low carbonation depths (< 10 mm) and no appreciable chlorides. Micro-cracking was observed in the samples recovered from the wall and dome. To date, the observed micro-cracking has had no apparent visible affect on the performance of the CCB concrete. (authors)

  17. Neutron radiography for the characterization of porous structure in degraded building stones

    International Nuclear Information System (INIS)

    As it is well known, the porous structure of stones can change due to different degradation processes that modify the characteristics of freshly quarried blocks. Their knowledge is fundamental for predicting the behavior of stones and the efficacy of conservative treatments. In this context, neutron radiography is a useful tool not only to visualize the structure of porous materials, but also to evaluate the degree of degradation and surface modifications resulting from weathering processes. Furthermore, since thermal neutrons suffer a strong attenuation by hydrogen, this technique is effective in order to investigate the amount of absorbed water in building materials. In the present work, we report a neutron radiography investigation of limestones cropping out in the South-Eastern Sicily and widely used as building stones in Baroque monuments of the Noto Valley. The analyzed samples have been submitted to cyclic salt crystallization that simulate degradation processes acting in exposed stones of buildings. The obtained results demonstrate the interest of neutron radiography to better understand deterioration processes in limestones and to acquire information useful for restoration projects

  18. Containment building hydrogen control methods related to degraded core accidents

    International Nuclear Information System (INIS)

    Degraded core accident-related release of hydrogen under some circumstances may threaten the integrity of pressurized water reactor containment buildings. This report provides a preliminary survey of a spectrum of possible approaches which could be adopted to maintain containment building integrity under accident conditions which lead to the release of hydrogen. Particular attention is directed to large, dry containment of the Zion and Indian Point designs. For any such possible accident, there exists a sequence of time intervals characterizing the accident scenario. This report considers the generic features of these intervals and discusses the suitability of various approaches to hydrogen accident control as related to the characteristics of the interval during which they are applied. It was found that various options exist for hydrogen control strategies and that their usefulness depends on the particular accident scenarios to be considered. Of all the hydrogen control approaches considered, a strategy of continuous inerting of the containment building is the only one which clearly eliminates the combustion hazard, does not involve adverse environmental effects, and succeeds in a way that is independent of the accident scenario

  19. 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.

  20. 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.

  1. Natural radioactivity concentrations in building materials

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Kazuo [Building Materials Research Inst., Tokyo (Japan); Asano, Kenji

    1998-01-01

    As part of our study program on environmental radiation levels is buildings, we have undertaken to measure the natural radioactivity, such as radium-226, thorium-232, and potassium-40 in various inorganic building materials. The specimens of their materials include cements, aggregates, concretes, asbestos cement slates, tiles, gypsum boards, rock wool boards, bricks, wall clays, soils, phosphorous ore, zirconia, zircon flower and zircon sand that used in Japan. The ranges and mean values of natural radioactivity concentrations existing in their materials are tabulated and evaluated. (author)

  2. Natural radioactivity concentrations in building materials

    International Nuclear Information System (INIS)

    As part of our study program on environmental radiation levels is buildings, we have undertaken to measure the natural radioactivity, such as radium-226, thorium-232, and potassium-40 in various inorganic building materials. The specimens of their materials include cements, aggregates, concretes, asbestos cement slates, tiles, gypsum boards, rock wool boards, bricks, wall clays, soils, phosphorous ore, zirconia, zircon flower and zircon sand that used in Japan. The ranges and mean values of natural radioactivity concentrations existing in their materials are tabulated and evaluated. (author)

  3. 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, in...... many cases such a coefficient would be highly appreciated, e.g. in interaction of industry and research or for the distinction and selection of suitable building materials throughout design and practise. This article first highlights the importance of drying experiments for hygrothermal...... characterisation of building materials on which the attempt is based to standardize the drying experiment as well as to derive a single number material coefficient. The drying itself is briefly reviewed and existing approaches are discussed. On this basis, possible definitions are evaluated. Finally, a drying...

  4. Natural radioactivity in Algerian building materials

    International Nuclear Information System (INIS)

    Samples of natural and manufactured building materials collected from Algiers have been analysed for 226Ra, 232Th and 40K using a high-resolution HPGe spectrometry system. The specific concentrations for 226Ra, 232Th and 40K, for the selected building materials, were ranging from (12 - 65 Bq.kg-1), (7 - 51 Bq.kg-1) and (36 - 675 Bq.kg-1), respectively. The measured activity concentrations for these natural radionuclides were compared to the reported data of other countries and to the world average activity of soil. Radium equivalent activities were calculated for the measured samples to assess the radiation hazards arising from using those materials in construction of dwellings. All building materials showed Raeq activities lower than the limit set up in the OECD report (370 Bq.kg-1), equivalent to external gamma dose of 1.5 mSv.y-1. (author)

  5. Radioactivity in building materials in Iraq

    International Nuclear Information System (INIS)

    Activity concentrations of 226Ra, 232Th and 40K 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 226Ra, 232Th 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. (author)

  6. Human exposure to emissions from building materials

    DEFF Research Database (Denmark)

    Kjærgaard, S.; Hauschildt, P.; Pejtersen, Jan;

    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 re...... effects by linoleum and carpet used and that changing to vinyl flooring may reduce these.......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...... respectively to clean air, to emissions from linoleum, from carpet, and from an alternative new vinyl. Measurements of objective and subjective effects were made.Results. Tear film stability decreased after exposure to linoleum. The nasal volume decreased near-significantly for all exposures. No effects were...

  7. 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.

  8. 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.

  9. Natural radioactivity of building materials in Syria

    International Nuclear Information System (INIS)

    A hundred sample of natural and manufactured Syrian building materials have been studied. A high pure Germanium detector in use was connected to S-100 MCA Master board and samples have been analysed by using micro sampo gamma spectrum analysis for their Thorium-232, Radium-226 and Potassium-40 content. Fourteen kinds of building materials were studied; bricks ceramic and fire soil, generally showed the greatest concentration of the above mentioned radionuclides. While the other products like sand, cement, marble, and limestone, contained very low activity. All samples fitted the range of criteria set up in the OECD-NEA report 1979. (author). 7 refs., 21 tabs., 24 figs

  10. 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.

  11. Proactive evaluation of potential and latent materials degradation phenomena

    International Nuclear Information System (INIS)

    A Proactive Materials Degradation Management (PMDM) project has been carried out at the Frontier Research Initiative (FRI), New Industry Creation Hatchery Center, Tohoku University for 5 years, as a part of a Nuclear Industries Safety Agency (NISA, now the Secretariat of the Nuclear Regulation Authority) project that was originally formed in 2007 to define an Aging Management Program that addresses unexpected structural material failures in Light Water Reactors (LWRs). Such a program required, therefore, the development of a life prediction capability for specific combinations of degradation modes, structural materials, and reactor components. In this paper, PIRT results for the aging degradation phenomena in LWR structural materials are introduced. (author)

  12. 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.

  13. Development of degradation D/B system for the containment building of NPP

    International Nuclear Information System (INIS)

    The Degradation D/B System is developed for digitalizing the history of the Containment building of nuclear power plant. It have 6 D/B which are consist of General, Design drawing, Material, Construction, ISI·SIT·ILRT D/B. For efficient operation of the system, utilities are also developed such as the aging and repair data management program for concrete and steel structures, the data search engine with various options helping users find what they want, and the data exchange program restoring and updating input data

  14. 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...

  15. Human exposure to emissions from building materials

    DEFF Research Database (Denmark)

    Kjærgaard, S.; Hauschildt, P.; Pejtersen, Jan; Mølhave, L.

    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...... found on peak flow, eye foam formation, tear fluid cells, or conjunctival epithelial damage. Among subjective evaluations only sound intensity rating was significant. A correlation was found between acute nose irritation rating and change in nasal volume.Conclusions. The findings indicate physiological...... effects by linoleum and carpet used and that changing to vinyl flooring may reduce these....

  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. Radiation dose assessment for building material

    International Nuclear Information System (INIS)

    A mathematical model for radiation dose assessment for building materials based on attenuation and build up for gamma rays of the natural emitters was studied in this work. This was done by calculate the air absorbed dose from elemental volume and integrate over the total wall volume, which uniformed density and activity concentration. The used form of the build-up is a mixing of exponential and linear form for Berger model [1]. To convert absorbed dose to effective dose for all natural emitter (include 137Cs in case of fallout), the dose rate conversion factors which were reported in UNSCEAR (1993) Report [2] and U. S. NCRP (1987) [3] was used. These factors are 0.7 Sv/Gy for adult and 0.8 Sv/Gy for children. A computer program for calculating the absorbed and the annual effective dose was prepared in MATLAB language. The program is applicable for wall or room building materials when walls consist of one or two layers. The obtained results were compared with published studies. (author)

  18. Overview of environmental materials degradation in light-water reactors

    International Nuclear Information System (INIS)

    This report provides a brief overview of analyses and conclusions reported in published literature regarding environmentally induced degradation of materials in operating light-water reactors. It is intended to provide a synopsis of subjects of concern rather than to address a licensing basis for any newly discovered problems related to reactor materials

  19. Interfacial degradation of organic composite material by irradiation in reactor

    International Nuclear Information System (INIS)

    Glass fiber reinforced plastics (GFRP) with many kinds of matrix resins were made of E glass treated with silane as the reinforced material. Degradation of shearing strength of GFRP irradiated at low temperature was determined. It was clear from the results of comparing the degradation process with the fractured surface that the degradation was very affected by the radiation resistance of the bonded part between resin and coupling agents. It means that we had to be careful in the choice of interfacial treatments and epoxy matrices corresponded to it. (S.Y.)

  20. 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

  1. Characterisation of natural occurring radioactive materials in building materials

    International Nuclear Information System (INIS)

    Naturally occurring radionuclides (U,Th and K) are known to be present in significant amounts in soil, building materials and recycled industrial waste products. These findings are of our concern since we are continuously being exposed to radiations from such radionuclides, be it at home or workplace. In the study, we have chosen several commonly used building materials such as; cement brick, roof asbestos, red-clay brick, ceiling asbestos and also cement produce which form a vital component in the construction industry. The gamma gross counting method was used to analyse gamma rays at energies 609 keV, 583 keV and 1460 keV using hyperpure germanium counter with 20% efficiency. The radium equivalent activity, Raeq were computed and our findings have shown that some of the samples exhibit a high level of radium equivalent activity, exceeding those of the normal limit recommended by UNSCEAR. (Author)

  2. Water chemistry and materials degradation in LWR'S

    International Nuclear Information System (INIS)

    Water chemistry plays a major role in corrosion, in erosion corrosion and in activity transport in NPPs; it impacts upon the operational safety of LWRs in two main ways: integrity of pressure boundary materials and activity transport and out-of-core radiation fields. A good control of water chemistry can significantly reduce these problems and improve plant safety, but economic pressures are leading to more rigorous operating conditions: fuel burnups are to be increased, higher efficiencies are to be achieved by running at higher temperatures and plant lifetimes are to be extended. Typical water chemistry specifications used in PWR and BWR plants are presented and the chemistry optimization is discussed. The complex interplay of metallurgical, mechanical and environmental factors in environmental sensitive cracking is shown, with details on studies for carbon steels, stainless steels and nickel base alloys. 20 refs., 8 figs., 4 tabs

  3. Rapid technique for determining building material radioactivity

    International Nuclear Information System (INIS)

    Rapid technique for determining building material radioactivity graphically, using nomogram of known uranium (226Ra), thorium (232Th), potassium contents is suggested. Nomogram usage permits to replace labour-consuming calculations of radionuclide specific activity by formula with simple rule imposition. Determination errors don't exceed 1-2%. The nomogram may be easily constructed selecting ranges of radionuclide concentration variation ranges, which are the most characteristic for the work region, and calculating scale values for U, Th and K by formula. Distance from uranium activity scale to U and Th total activity scale as well as scale factor of total specific activity are calculated by formula

  4. Development of proactive technology against nuclear materials degradation

    International Nuclear Information System (INIS)

    As the nuclear power plants are getting older, the extent of materials degradation increases and unexpected degradation mechanisms may occur under complex environments, including high-temperature and pressure, radiation and coolant. The components in the primary system are maintained at the temperature of 320 .deg. C, pressure of 2500 psi, and reactor internals are exposed to fast neutrons. The pipes and nozzles are affected by the mechanical, thermal and corrosive cyclic fatigue stresses. Since the steam generator tubes are affected by both primary and secondary coolants, the materials degradation mechanisms are dependent upon the multiple or complex factors. In this report, we make contribution to the enhancement of reactor safety by developing techniques for predicting and evaluating materials behaviors in nuclear environments. The research product in the following five areas, described in this report, plays a vital role in improving the safe operation of nuclear reactors, upgrading the level of skills and extending the use of nuclear power. Development of corrosion control and protection technology Development of fracture mechanical evaluation model of reactor pressure Development of prediction and analysis technology for radiation damage Development of advanced diagnostic techniques for micro-materials degradation Development of core technology for control of steam generator degradation

  5. 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.

  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. 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.

  8. 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

  9. The façades along the Cassaro in Palermo: historical-building characterization, degradation, restoration norms for interventions

    Directory of Open Access Journals (Sweden)

    Giovanni Fatta

    2009-03-01

    Full Text Available The good-will to operate in the old town privileging the history and the maintenance of historic buildings, is manifest in this study on the Vittorio Emanuele monumental street, the foundation axis of Palermo, and it’s architectural degraded and disfigured fronts. The search concerning sixty civil buildings is based initially on a cognitive process that includes historical analysis, geometric and dimensional survey, investigation on constituent materials and decay systems, in relation to environmental or anthropic causes. The study includes a design proposal that, according to the individuality of cases, it would represent an intervention code about some recurrent critical aspects on which it’s possible to intervene only applying codified procedures. The proposed designs show so an application to concrete cases, not abdicating to involve physical and economic urban environment: the re-qualification of building materials and architectural language would respect the historical image without depressing the market demands.

  10. Thermal aging degradation assessment of domestic nuclear polymer materials

    International Nuclear Information System (INIS)

    It is well-known that polymer materials such as plastics and elastomers are easily degraded under nuclear environments, which always raises great concern on nuclear safety. Nevertheless, aging degradation data on domestic polymer materials are seldom available. In order to assess the thermal aging domestic nuclear polymers, PBT (Poly Butylene Telephtalate), EPR (Ethylene Propylene Rubber), SIR(Silicon Rubber) degradation, therefore, are chosen for the experimental tests. In this study, the reduction of elongation of the materials are tested and measured for the degradation evaluation. Results show that in case of EPR it takes 1860.47hr, 390.63hr, and 172.12hr at 140 .deg. C, 155 .deg. C, and 170 .deg. C, respectively, for 60% elongation reduction, which produces the activation energy of 1.25eV that is very close to that in the international report. Similarly, the activation of 60% elongation reduction of PBT turns out to be 1.20eV while that of SIR is revealed to be 0.94eV

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

    DEFF Research Database (Denmark)

    Andersen, Birgitte; Frisvad, Jens Christian; Søndergaard, Ib; Rasmussen, Ib S.; Larsen, Lisbeth S.

    2011-01-01

    8 contact plates from materials with visible fungal growth. Fungal identifications and information on building material components were analyzed using multivariate statistic methods to determine associations between fungi and material components. The results confirmed that Penicillium chrysogenum...

  12. 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.

  13. 327 Building Justification for Continued Operations for Curium Material Removal

    International Nuclear Information System (INIS)

    The purpose of this document is to identify and analyze the hazards associated with the removal of the curium material from the 327 Building. This Justification for Continued Operations (JCO) becomes a part of the 327 Building Safety Basis Documentation

  14. The atmospheric agents which are responsible for the building degradation

    Energy Technology Data Exchange (ETDEWEB)

    Romanovsky, V.

    1994-06-01

    This short paper deals with the main diseases responsible for historic buildings damages and shows some illustrations of these damages. Usually they are generated by the environment aggressiveness. In the same time, the atmospheric factors being at their origin are depicted namely: pluviometry, temperature and sunniness. 10 figs.

  15. Nuclear-waste-package materials degradation modes and accelerated testing

    International Nuclear Information System (INIS)

    This report reviews the materials degradation modes that may affect the long-term behavior of waste packages for the containment of nuclear waste. It recommends an approach to accelerated testing that can lead to the qualification of waste package materials in specific repository environments in times that are short relative to the time period over which the waste package is expected to provide containment. This report is not a testing plan but rather discusses the direction for research that might be considered in developing plans for accelerated testing of waste package materials and waste forms

  16. Saving energy for ventilation by careful selection of building materials

    DEFF Research Database (Denmark)

    Wargocki, Pawel; Knudsen, Henrik Nellemose

    2008-01-01

    The main objective of the research project described in this paper was to study the potential of reducing energy used for ventilating buildings by using low-polluting building materials without compromising indoor air quality.......The main objective of the research project described in this paper was to study the potential of reducing energy used for ventilating buildings by using low-polluting building materials without compromising indoor air quality....

  17. Nano insulating materials and energy retrofit of buildings

    Science.gov (United States)

    Casini, Marco

    2016-06-01

    The article offers an analysis of the use of nanotechnological insulation materials (NIMs) for energy upgrading of buildings, illustrating the possibility of their integration into the building envelope and the benefits achievable in terms of architectural quality, comfort and energy saving, within the new framework of European legislation aimed at achieving Zero energy buildings. Particular reference is given to Fibre Reinforced Aerogel Blankets for the building envelope, especially interesting for their wide possible applications even combined with phase change materials.

  18. 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.

  19. Physical and mechanical properties of degraded waste surrogate material

    International Nuclear Information System (INIS)

    This paper discusses rock mechanics testing of surrogate materials to provide failure criteria for compacted, degraded nuclear waste. This daunting proposition was approached by first assembling all known parameters such as the initial waste inventory and rock mechanics response of the underground setting after the waste is stored. Conservative assumptions allowing for extensive degradation processes helped quantify the lowest possible strength conditions of the future state of the waste. In the larger conceptual setting, computations involve degraded waste behavior in transient pressure gradients as gas exits the waste horizon into a wellbore. Therefore, a defensible evaluation of tensile strength is paramount for successful analyses and intentionally provided maximal failed volumes. The very conservative approach assumes rampant degradation to define waste surrogate composition. Specimens prepared from derivative degradation product were consolidated into simple geometries for rock mechanics testing. Tensile strength thus derived helped convince a skeptical peer review panel that drilling into the Waste Isolation Pilot Plant (WIPP) would not likely expel appreciable solids via the drill string

  20. Pozzolanic mortars based on waste building materials for the restoration of historical buildings

    OpenAIRE

    Pašalić Snežana; Vučetić Snežana; Zorić Dmitar; Ducman Vilma; Ranogajec Jonjaua

    2012-01-01

    The environmental aspects of waste building materials have been of great interest in recent years. For the sector of building materials this means increased recycling, reduction of energy consumption and natural resources preservation. This also presents an important contribution in the field of environmental protection. The work deals with the development of pozzolanic mortars made of waste building materials, ground red structure bricks and raw clay materials of inadequate characteris...

  1. Degradation of elastomeric gasket materials in PEM fuel cells

    International Nuclear Information System (INIS)

    Polymer electrolyte membrane (PEM) fuel cell stack requires gaskets in each cell to keep the reactant gases within their respective regions. Long-term durability of the fuel cell stacks depends heavily on the functionality of the gaskets. Both the leachants from the seal materials and the cracking of the seals are of great concern to the overall durability of the fuel cell stacks. The degradation of four commercially available gasket materials was investigated in a PEM fuel cell environment in this study. Optical microscopy reveals that the degradation starts with surface roughness from the early stage of exposure and finally results in cracks over time. Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) were employed to study the surface chemistry of the gasket materials before and after exposure to the PEM fuel cell environment over time. Results from these analyses indicate that the surface chemistry changed initially as a manifestation of the chemical degradation and proceeded via de-cross-linking and chain scission in the backbone. Atomic adsorption spectrometry analysis was used to identify the leachants in the soaking solution from the gasket materials. The effect due to applied stress is reported as well

  2. 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.

  3. 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.

  4. 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.

  5. Natural activities of primordial radionuclides in building materials

    International Nuclear Information System (INIS)

    Seven kinds of building materials were analysed for 232Th, 238U and 40K using a direct gamma counting method. The radium equivalent activities for different building materials have been estimated. The calculated radium equivalent activities (Raeq) for all building materials are slightly higher (74.5 to 191 Bq/kg) than the world average value for soil (89 Bq/kg) and they are well below the maximum permissible limit 370 Bq/kg. (author)

  6. Toxicity of building materials : a key issue in sustainable construction

    OpenAIRE

    Torgal, Fernando Pacheco; Jalali, Said

    2010-01-01

    Avoiding the use of toxic building materials is one of the principles of sustainable construction. Current residential buildings frequently contain many toxic materials, some of which are even compliant with legal regulations in Europe and Portugal. Part of the problem is due to the fact that architects and civil engineers receive no education on the toxicity of building materials. Another problem is related to the fact that the regulations about toxicity thresholds are influenced by economic...

  7. 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).

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

    International Nuclear Information System (INIS)

    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)

  9. 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.

  10. Significant aspects on thermal degradation of hybrid biocomposite material

    Science.gov (United States)

    Bavan, D. Saravana; Kumar, G. C. Mohan

    2013-06-01

    Interest in use of bio fibers is increasing rapidly in structural and automotive applications because of few important properties such as low density, mechanical properties, renewability, biodegradation and sustainability. The present work is focused on fabricating a hybrid bio-composite material processed through compression molding technique. Natural fibers of maize and jute with bio polymeric resin of epoxidized soya bean oil are used as a matrix in obtaining a hybrid bio composite material. Thermal degradation of the prepared material is studied through Thermal gravimetric analyzer. Chemical treatment of the fibers was performed to have a better adhesion between the fibers and the matrix. The work is also surveyed on various parameters influencing the thermal properties and other aspects for a hybrid bio composite material.

  11. Dependence of indoor 222Rn level on building materials

    International Nuclear Information System (INIS)

    The radionuclide contents of typical building materials used in Hong Kong were studied by γ spectroscopic analysis. The physical properties of these building materials affecting the production and transportation of 222Rn to the surrounding air were examined; these include the emanation coefficient of 2'22Rn of the material, the diffusion coefficient of 222Rn in the material and the effect of surface coating and temperature on the rate of 222Rn exhalation. Results obtained in this study explain the indoor 222Rn concentration observed in our previous surveys and also suggest that the main source of indoor 222Rn in Hong Kong is building material. (3 figs., 4 tabs.)

  12. 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

  13. Influence of building materials process technology on radon exhalation

    International Nuclear Information System (INIS)

    The building materials were produced through changing raw material ingredient, baking temperature, pressure difference between surface and interior of building material, grain diameter etc. Experiment indicates that change of raw material ingredient ratio can obviously influence the radon exhalation from building material, followed by baking temperature; and pressure difference does not have significant influence on radon exhalation. For the factory to produce shale-brick, the radon exhalation is relatively low under the condition that coal gangue accounts for 40%-50%, the grain diameter is less than 2 mm, the baking temperature is about 960 degree C or 1 020 degree C and the pressure difference is 85 kPa. (authors)

  14. Innovated Building Material's Interactions with Structural Form in Architectural Projects

    OpenAIRE

    Mozaikci, Begüm

    2009-01-01

    ABSTRACT: Interpretation of building materials into architectural form, is gaining greater interest and attention due to the conservation of architectural heritage. This study highlight, the influences of technological developments of building materials and their interactions with structural form in architectural design projects. Architectural form and decisions can potentially effects by introduced new materials and this study focus on the interaction of new material and structural form...

  15. Degradation of Spacecraft Materials in the Space Environment

    Science.gov (United States)

    Miller, Sharon K. R.; Banks, Bruce A.

    2010-01-01

    When we think of space, we typically think of a vacuum containing very little matter that lies between the Earth and other planetary and stellar bodies. However, the space above Earth's breathable atmosphere and beyond contains many things that make designing durable spacecraft a challenge. Depending on where the spacecraft is flyng, it may encounter atomic oxygen, ultraviolet and other forms of radiation, charged particles, micrormeteoroids and debris, and temperature extremes. These environments on their own and in combination can cause degradation and failure of polymers, composites, paints and other materials used on the exterior of spacecraft for thermal control, structure, and power generation. This article briefly discusses and gives examples of some of the degradation experienced on spacecraft and night experiments as a result of the space environment and the use of ground and space data to predict durability.

  16. Radon generation and transport in building materials and soils

    International Nuclear Information System (INIS)

    Radon-222 exhalation from building construction materials is a major source of radiation exposure for apartment dwellers who make up a large proportion of the population. The exhalation rate is a complex function of many parameters. This paper presents an analytical model in describing the physical processes of 222Rn release from 226Ra-bearing materials of building walls. (authors)

  17. Prediction of degradation and fracture of structural materials

    International Nuclear Information System (INIS)

    Prediction of materials performance in an engineering integrity context requires the underpinning of predictive modelling tuned by inputs from design, fabrication, operating experience, and laboratory testing. In this regard, in addition to fracture resistance four important areas of time dependent degradation are considered - mechanical, environmental, irradiation and thermal. The status of prediction of materials performance is discussed in relation to a number of important components such as LWR reactor pressure vessels and steam generators, and Fast Reactor high temperature structures. In each case the role of materials modelling is examined and the balance of factors which contribute to the overall prediction of component integrity/reliability noted. Structural integrity arguments must follow a clear strategy if the required level of confidence is to be established. Various strategies and their evolution are discussed. (author)

  18. Investigation of composite material degradation indicators using acoustic measurement: comparison with laser vibrometry

    Czech Academy of Sciences Publication Activity Database

    Fíla, Tomáš; Urushadze, Shota; Kytýř, Daniel; Valach, Jaroslav; Šperl, Martin

    Prague: Czech Technical University in Prague, Faculty of Transportation Sciences, 2012 - (Jiroušek, O.; Kytýř, D.), s. 35-38 ISBN 978-80-01-05062-0. [Bilateral Czech/German Symposium, Experimental methods and numerical simulation in engineering sciences/13./. Telč (CZ), 05.06.2012-08.06.2012] R&D Projects: GA ČR(CZ) GAP105/10/2159 Grant ostatní: Grant Agency of the Czech Technical University in Prague(CZ) SGS12/205/OHK2/3T/16 Institutional support: RVO:68378297 Keywords : attenuation decrement * fibre composite * material degradation * fatique Subject RIV: JM - Building Engineering

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

    International Nuclear Information System (INIS)

    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.

  20. 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.

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

    OpenAIRE

    Kim, Kyoung-Woo; Young-Sun JEONG

    2014-01-01

    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 acous...

  2. Investigating the presence of hazardous materials in buildings

    International Nuclear Information System (INIS)

    Environmental hazards in buildings can be found in the air, on exposed surfaces, or hidden in roofs, walls, and systems. They can exist in buildings in solid, liquid, and gaseous states. A sound methodology for investigating the presence of environmental hazards in buildings should include several components. The first step in planning an investigation of environmental hazards in buildings is to ascertain why the investigation is to be performed. Research should be performed to review available documentation on the building. Next, a visual inspection of the building should be performed to identify and document existing conditions, and all suspect materials containing environmental hazards. Lastly, samples of suspect materials should be collected for testing. It is important to sample appropriate materials, based on the information obtained during the previous steps of the investigation. It is also important to collect the samples using standard procedures. Pollutants of concern include asbestos, lead, PCBs, and radon

  3. Building

    OpenAIRE

    Seavy, Ryan

    2014-01-01

    Building for concrete is temporary. The building of wood and steel stands against the concrete to give form and then gives way, leaving a trace of its existence behind. Concrete is not a building material. One does not build with concrete. One builds for concrete.

  4. Building materials as sources of indoor exposure to ionizing radiation

    International Nuclear Information System (INIS)

    The thesis deals with the radioactivity of Finnish building materials and of industrial wastes or residues which can be used as building materials or as mixing substances of such materials. The external and internal exposure to radiation from building materials is described. The study also discusses with the methods used for measuring concentrations of natural and artificial gamma emitters in different kinds of materials and the amount of radon exhaling from building materials. A computational method for assessing the gamma ray exposure inside dwellings is desribed, and the results are compared with those of other corresponding methods. The results of the simple method described here are in good agreement with those obtained with the more refined Monte Carlo technique

  5. NANOTECHNOLOGY IN OUR CENTURY AND ITS EFFECTS ON BUILDING MATERIALS

    OpenAIRE

    PERKER, Z. Sevgen

    2010-01-01

    Nanotechnology is the study and control of matter at dimensions nanometers. Nanotechnology is also design, fabrication and application of nanostructures and nanomaterials. The research on nanotechnology is evolving and expanding very rapidly every discipline of science. One of them is material science. Nanoscale science and technology gives us unique opportunities to develop revolutionary building materials. This study focuses primarily on nanotechnology and its effects on building materials.

  6. Natural radioactivity level of main building materials in Baotou, China

    International Nuclear Information System (INIS)

    A survey was done on natural radioactivity level and annual effective dose rate of main building materials in Baotou, China. The natural radionuclides of 40K, 232Th and 226Ra in main building materials collected from Baotou were measured using NaI γ-ray spectrometry and the measured data were analyzed according to the national standards and radiological protection principles of the European Commission. The specific activities of 40K, 232Th and 226Ra in the building materials samples were 218.82-1145.92, 19.75-1.32.50 and 11.46-82.66 Bq/kg, respectively. The internal and external exposure indexes of building materials were 0.06-0.41 and 0.28-0.70, respectively. The annual effective dose equivalent was 0.41-0.97 mSv/y. This justifies the production and sale of the main building materials, as both the internal and external exposure indexes of building materials are less than 1. The effective dose rate of ash brick is 0.97 mSv/y, while the maximum acceptable value is 1 mSv/y. Therefore, it is necessary to control the amount of industrial waste residue in building materials to avoid unnecessary radioactive exposure to residents. (authors)

  7. Degradation of Piezoelectric Materials for Energy Harvesting Applications

    International Nuclear Information System (INIS)

    The purpose of energy harvesting is to provide long term alternatives to replaceable batteries across a number of applications. Piezoelectric vibration harvesting provides advantages over other transduction methods due to the ability to generate large voltages even on a small scale. However, the operation in energy harvesting is different from typical sensors or actuators. The applied stress is often at the material limit in order to generate the maximum power output. Under these conditions, the degradation of the materials becomes an important factor for long term deployment. In this work bimorph piezoelectric beams were sub jected to lifetime testing through electromagnetic tip actuation for a large number of cycles. The results of two measurement series at different amplitudes are discussed. The dominant effect observed was a shift in mechanical resonance frequencies of the beams which could be very detrimental to resonant harvesters

  8. Gradual surface degradation of restorative materials by acidic agents.

    Science.gov (United States)

    Hengtrakool, Chanothai; Kukiattrakoon, Boonlert; Kedjarune-Leggat, Ureporn

    2011-01-01

    The aim of this study was to investigate the effect of acidic agents on surface roughness and characteristics of four restorative materials. Fifty-two discs were created from each restorative material: metal-reinforced glass ionomer cement (Ketac-S), resin-modified glass ionomer cement (Fuji II LC), resin composite (Filtek Z250), and amalgam (Valiant-PhD); each disc was 12 mm in diameter and 2.5 mm thick. The specimens were divided into four subgroups (n=13) and immersed for 168 hours in four storage media: deionized water (control); citrate buffer solution; green mango juice; and pineapple juice. Surface roughness measurements were performed with a profilometer, both before and after storage media immersion. Surface characteristics were examined using scanning electron microscopy (SEM). Statistical significance among each group was analyzed using two-way repeated ANOVA and Tukey's tests. Ketac-S demonstrated the highest roughness changes after immersion in acidic agents (pValiant-PhD and Filtek Z250 illustrated some minor changes over 168 hours. The mango juice produced the greatest degradation effect of all materials tested (p<0.05). SEM photographs demonstrated gradual surface changes of all materials tested after immersions. Of the materials evaluated, amalgam and resin composite may be the most suitable for restorations for patients with tooth surface loss. PMID:21903509

  9. 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.

  10. Material degradation analysis and maintenance decisions based on material condition monitoring during in-service inspections

    International Nuclear Information System (INIS)

    The degradation of the material in critical components is shown to be an effective measure which can be used to compute the risk adjusted economic penalty associated with different maintenance decisions. The approach of estimating the probability, with confidence interval, of the time that a prescribed degradation level is exceeded is shown to be practical, as demonstrated in the analysis of irradiated fuel cladding. The methodology for the estimation of the probability is predicated on the existence of a parsimonious and robust mixed-effects model of the evolution of the degradation. This model, in general, relates measured surrogates of the degradation level to computed or measured variables, which characterize the environment during the operating history of the component. We propose and demonstrate the efficacy of using an artificial neural network, constructed via a genetic supervisor, as an aid in developing the requisite mixed-effects model and testing its continued validity as new data are obtained

  11. Natural activity of 40K in some Chilean building materials

    International Nuclear Information System (INIS)

    Knowledge of the natural level of radioactivity is important to assess the influence of gamma radiation exposure in building materials. The main sources of external radiation exposure in buildings are members of the uranium and thorium decay chains and 40K occurring naturally in building materials, which emit gamma rays.The specific activity of building materials has been reported for many countries. However, for Chilean building materials no such data are available. A study of 40K speciactivity on building materials was carried out with gamma spectrometric system based on high-purity germanium detector. The 40K activity was measured directly by its own gamma-ray line at 1460.8 keV. Samples of gypsum, cement, brick and cement and gravel mixture, widely used in Chile, were used on this work. The samples were corrected by moisture content and the geometrical conditions has been normalized to avoid volumetric corrections. All preliminary results are below the world average of 500 Bq/kg for building materials reported by UNSCEAR

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

    OpenAIRE

    Oladipupo OLOMO; Olufikayo ADERINLEWO; Moses TANIMOLA; Silvana CROOPE

    2012-01-01

    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 concr...

  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. Green Building Construction Thermal Isolation Materials (Rockwool)

    OpenAIRE

    M. Itewi

    2011-01-01

    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...

  15. 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.

  16. Surface Treatment of Building Materials with Water Repellent Agents

    NARCIS (Netherlands)

    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.

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

    International Nuclear Information System (INIS)

    The natural radioactivity levels of the commonly used building materials collected from Changzhi, China was analysed using gamma-ray spectroscopy. The activity concentrations of 226Ra, 232Th and 40K 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. (authors)

  18. Pozzolanic mortars based on waste building materials for the restoration of historical buildings

    Directory of Open Access Journals (Sweden)

    Pašalić Snežana

    2012-01-01

    Full Text Available The environmental aspects of waste building materials have been of great interest in recent years. For the sector of building materials this means increased recycling, reduction of energy consumption and natural resources preservation. This also presents an important contribution in the field of environmental protection. The work deals with the development of pozzolanic mortars made of waste building materials, ground red structure bricks and raw clay materials of inadequate characteristics for the production of ceramic materials. Based on the results of historical mortar characterizations, a group of mortars with specific characteristics (satisfied durability, good compatibility with a historical mortar was prepared. The potential of the waste materials and domestic clay materials application in the production of pozzolanic mortars was confirmed. In addition to the waste management, pozzolanic mortars were designed taking into account the existing conventions in the area of culture heritage.

  19. 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.

  20. Building Investigation: Material or Structural Performance

    OpenAIRE

    Yusof M.Z.

    2014-01-01

    Structures such as roof trusses will not suddenly collapse without ample warning such as significant deflection, tilting etc. if the designer manages to avoid the cause of structural failure at the material level and the structural level. This paper outlines some principles and procedures of PDCA circle and QC tools which can show some clues of structural problems in terms of material or structural performance

  1. Building Investigation: Material or Structural Performance

    Directory of Open Access Journals (Sweden)

    Yusof M.Z.

    2014-03-01

    Full Text Available Structures such as roof trusses will not suddenly collapse without ample warning such as significant deflection, tilting etc. if the designer manages to avoid the cause of structural failure at the material level and the structural level. This paper outlines some principles and procedures of PDCA circle and QC tools which can show some clues of structural problems in terms of material or structural performance

  2. 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

  3. Environmental effect of structural solutions and building materials to a building

    International Nuclear Information System (INIS)

    The field of building environmental assessment tools has become a popular research area over the past decade. However, how the service life of a building affects the results of the environmental assessment of a building has not been emphasised previously. The aim of this study is to analyse how different structural solutions and building materials affect the results of the environmental assessment of a whole building over the building's life cycle. Furthermore, how the length of the building's service life affects the results is analysed. The environmental assessments of 78 single-family houses were calculated for this study. The buildings have different wall insulations, claddings, window frames, and roof materials, and the length of the service life varies from 60 years up to 160 years. The current situation and the future of the environmental assessment of buildings are discussed. In addition, topics for further research are suggested; for example, how workmanship affects the service life and the environmental impact of a building should be studied

  4. State of the art review of degradation processes in LMFBR materials. Volume II. Corrosion behavior

    International Nuclear Information System (INIS)

    Degradation of materials exposed to Na in LMFBR service is reviewed. The degradation processes are discussed in sections on corrosion and mass transfer, erosion, wear and self welding, sodium--water reactions, and external corrosion. (JRD)

  5. Strengthening of building structures using carbon composite materials

    Directory of Open Access Journals (Sweden)

    N.V. Paranicheva

    2010-03-01

    Full Text Available Currently, the question of ensuring the reliability of various building structures both at the stage of their construction and during operation is very urgent. There are a lot of different ways and constructive methods of structures strengthening. Аt the same time, traditional ways of concrete structures strengthening with steel reinforcement are such expensive, time consuming and in some cases require to interrupt the building operation. As an alternative, it is proposed to use composite materials based on high-strength carbon fibers.The authors consider the properties, advantages, disadvantages and the methods of application of these materials. This article presents results of a technical survey carried out in a public building in 2009. In this building the CFRP was used to strengthen concrete slabs, resting on the crossbar consoles. The calculation of the strength is adduced and the section selection is made. The authors demonstrate their conclusions about the feasibility of using carbon composite materials.

  6. Probabilistic analysis for fatigue strength degradation of materials

    Science.gov (United States)

    Royce, Lola

    1989-01-01

    This report presents the results of the first year of a research program conducted for NASA-LeRC by the University of Texas at San Antonio. The research included development of methodology that provides a probabilistic treatment of lifetime prediction of structural components of aerospace propulsion systems subjected to fatigue. Material strength degradation models, based on primitive variables, include both a fatigue strength reduction model and a fatigue crack growth model. Linear elastic fracture mechanics is utilized in the latter model. Probabilistic analysis is based on simulation, and both maximum entropy and maximum penalized likelihood methods are used for the generation of probability density functions. The resulting constitutive relationships are included in several computer programs, RANDOM2, RANDOM3, and RANDOM4. These programs determine the random lifetime of an engine component, in mechanical load cycles, to reach a critical fatigue strength or crack size. The material considered was a cast nickel base superalloy, one typical of those used in the Space Shuttle Main Engine.

  7. γ-ray shielding effect of various building materials

    International Nuclear Information System (INIS)

    It is necessary to know the γ-ray attenuation coefficients and the dose buildup factors for various building materials in order to evaluate the γ-ray shielding factor of the residential houses in the reactor accident. As a matter of fact, however, there is few information about these values. This report describes measurements of the linear attenuation coefficients and dose buildup factors for the typical building materials used in Japan and estimation of the γ-ray shielding effects of these materials. (author)

  8. Plasma technologies application for building materials surface modification

    Science.gov (United States)

    Volokitin, G. G.; Skripnikova, N. K.; Volokitin, O. G.; Shehovtzov, V. V.; Luchkin, A. G.; Kashapov, N. F.

    2016-01-01

    Low temperature arc plasma was used to process building surface materials, such as silicate brick, sand lime brick, concrete and wood. It was shown that building surface materials modification with low temperature plasma positively affects frost resistance, water permeability and chemical resistance with high adhesion strength. Short time plasma processing is rather economical than traditional processing thermic methods. Plasma processing makes wood surface uniquely waterproof and gives high operational properties, dimensional and geometrical stability. It also increases compression resistance and decreases inner tensions level in material.

  9. 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.

  10. Survey and specimen taking of building materials which are destined for house building in The Netherlands

    International Nuclear Information System (INIS)

    This investigation deals with the following items: (a) Some building materials cause an increase of the natural radioactive radiation level indoors, especially building materials containing a certain kind of phosphogypsum. The radiation level depends among other things on the applied quantity of building materials and on the location in the building (walls, floors or roofs, etc.). The soil underneath dwellings can also be an important radiation source. The report gives a listing of the kind of building materials used for dwellings in The Netherlands, both present ones as well as possible future ones. A survey of the quantities applied and the location of application in dwellings is also given. The different types of soil underneath the dwellings are discussed. (b) Samples were collected from various factories, dealers and other sources (both present and future samples) of the most important building materials and components thereof. The samples were handed over to Division of Technology for Society TNO, Radiological Service TNO and Netherland Energy Research Foundation, in order to measure the activity concentrations and the radon exhalations. A listing of the samples is given. (Auth.)

  11. 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.

  12. 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

  13. Radon exhalation rates from some building construction materials using SSNTDs

    International Nuclear Information System (INIS)

    Radon appears mainly by diffusion processes from the point of origin following α- decay of 226Ra in underground soil and building materials used. in the construction of floors, walls, and ceilings. In dwellings main source of radon are soil or rock underneath, building materials and portable water supplies. The major release of radon indoors is from building construction materials used. The radon measurements on the ground can give a clue about the hidden uranium. The exposure of population to high concentrations of radon and its daughters for a long period leads to pathological effects like the respiratory functional changes and the occurrence of lung cancer. In the present investigations radon exhalation rates from some soil and other building materials like fly ash, cement and sand collected from Panchkula, Ambala, Yamunanagar, Kurukshetra, Karnal and Panipat districts of Haryana have been estimated. For the measurement of radon concentration in these samples we used α-sensitive LR-115 type II plastic track detectors. The mass and the surface exhalation rates of radon emanated from these samples have also been calculated. The aim of study is the possible health risk assessment due to emission of radiation from building construction materials. (author)

  14. Evaluation of waste as a comparative criterion for building materials

    OpenAIRE

    Gómez Soberón, José Manuel Vicente; Gómez Soberón, M. Consolació; Cabrera Covarrubias, Francisca Guadalupe; Corral Higuera, Ramón; Gámez García, Diana C.; Guerrero Díaz, Antonio; Gómez Soberón, Luis Alberto

    2012-01-01

    In this paper, it analyzes and compares the use of three different materials (Reinforced Concrete -R. C.-, Steel and Wood) usable for the building, and construction processes that this entails. The analysis aimed to investigate which of the three materials is the most appropriate from the perspective of sustainability in order to propose alternatives that minimize the impact they have on the environment. Today, concrete is the material most commonly used in construction, and th...

  15. Design Of Material Access Shielding Door Of ISFSF Building

    International Nuclear Information System (INIS)

    Base on the planning to maintain of the air pressure in the reactor building, the design of material access shielding door in the ISFSF building has been done. By the installation designed, the air pressure condition in the reactor building well meet the design criteria. The system requires 12 pieces of steel beam L 4 x 3 x 1/2 inches ASTM A36 and 6 pieces steel plate by 2400 x 1200 x 3 mm dimension ASTM A514. This paper concluded that this design is feasible to be realized

  16. Thermal and chemical degradation of inorganic membrane materials. Topical report

    Energy Technology Data Exchange (ETDEWEB)

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

    1994-04-01

    This report describes the results of a literature review to evaluate the long-term thermal and chemical degradation of inorganic membranes that are being developed to separate gaseous products produced by the gasification or combustion of coal in fixed-, fluidized-, and entrained-bed gasifiers, direct coal-fired turbines, and pressurized-fluidized-bed combustors. Several impurities, such as H{sub 2}S, NH{sub 3}, SO{sub 2}, NO{sub x}, and trace metal compounds are generated during coal conversion, and they must be removed from the coal gas or the combustor flue gas to meet environmental standards. The use of membranes to separate these noxious gases is an attractive alternative to their removal by sorbents such as zinc titanate or calcium oxide. Inorganic membranes that have a high separation efficiency and exhibit both thermal and chemical stability would improve the economics of power generation from coal. The U.S. Department of Energy is supporting investigations to develop inorganic membranes for separating hydrogen from coal gas streams and noxious impurities from hot coal- and flue-gas streams. Membrane materials that have been investigated in the past include glass (silica), alumina, zirconia, carbon, and metals (Pd and Pt).

  17. Radon exhalation from building materials used in Libya

    International Nuclear Information System (INIS)

    Radon exhalation rates have been determined for various different samples of domestic and imported building materials available in the Libyan market for home construction and interior decoration. Radon exhalation rates were measured by the sealed-can technique based on CR-39 nuclear track detectors (NTDs). The results show that radon exhalation rates from some imported building materials used as foundations and for decoration are extremely high, and these samples are the main sources of indoor radon emanation. Radium contents and annual effective doses have also been estimated. - Highlights: • Radon exhalation was measured in building materials (BM) by the can technique. • The results are mostly within the worldwide range of values found in BM samples. • Two high values of radon concentration have been observed from granite and marble. • No significant risk to the human beings due to the presence of radon in the homes

  18. 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

  19. Studies on natural radioactivity of some egyptian building materials

    International Nuclear Information System (INIS)

    Using high-resolution y-rays spectrometry, the natural radioactivity of 14 samples of natural and o manufactured Egyptian building materials have been investigated. The samples were collected from local market and construction sites. From the measured gamma-ray spectra, specific activities were determined. The radium equivalent activity in each sample was estimated. Radiological evaluations of these materials indicate that all materials meet the external gamma-ray dose limitation. Calculation of concentration indices by assuming a Markkanen room model is constructed from these materials, to find the excess gamma-ray dose taken over that received from the outdoors. The Austrian Standard ONORM S 5200 is used in testing the building materials

  20. Seismic response of base isolated auxiliary building with age related degradation

    International Nuclear Information System (INIS)

    The aging of an isolator affects not only the mechanical properties of the isolator but also the dynamic properties of the upper structure, such as the change in stiffness, deformation capacity, load bearing capacity, creep, and damping. Therefore, the seismic response of base isolated structures will change with time. The floor response in the base isolated nuclear power plants (NPPs) can be particularly changed because of the change in stiffness and damping for the isolator. The increased seismic response due to the aging of isolator can cause mechanical problems for many equipment located in the NPPs. Therefore, it is necessary to evaluate the seismic response of base isolated NPPs with age related degradation. In this study, the seismic responses for a base isolated auxiliary building of SHIN KORI 3 and 4 with age related degradation were investigated using a nonlinear time history analysis. Floor response spectrums (FRS) were presented with time for identifying the change in seismic demand under the aging of isolator

  1. Measurement of radioactivity in building materials in Serbia

    International Nuclear Information System (INIS)

    This work presents a comprehensive study of natural radioactivity in 720 building materials imported in Serbia in 2012. Radioactivity concentrations of 226Ra, 232Th and 40K in the studied samples range from -1, respectively. The maximum values of 226Ra and 232Th activity concentrations were found in zirconium mineral, while the highest 40K activity concentration was in the feldspar. Based on the obtained radionuclide concentrations, radium equivalent activity, air absorbed dose rate, annual effective dose, external and internal hazard indices, gamma and alpha index due to radon inhalation were evaluated to assess the potential radiological hazard associated with these building materials. (author)

  2. Materials degradation analysis of RAF's by instrumented indentation test

    International Nuclear Information System (INIS)

    Full text of publication follows: Reduced activation ferritic/martensitic steels (RAFs) have been expected to be a candidate material for blanket of fusion reactor, because of their excellent high-temperature strength. Their outstanding strength performance is attributable to the combined strengthening mechanisms of matrix and various grain boundaries. However, it is by no means easy to separate the contributions of such strengthening factors because of extremely fine and complicated microstructure. In this study, the instrumented indentation test was carried out under a wide variety of maximum indentation loads using the creep ruptured specimens to clarify the contribution of each microstructural factor to their strength and materials degradation. The material used in this study was JLF-1 (Fe-9Cr-2W-0.2V-0.08Ta) and the rotor steel (Fe-10Cr-1Mo-1W-VNbN) was also used as reference steel. The indentation test was applied to the as-tempered steels and the creep ruptured specimens (JLF-1: 873 K/160 MPa, tr =3047 h, the rotor steel: 923 K/98 MPa, tr=4524 h). The test was performed at the maximum loads ranging from 1 to 1000 mN. The hardness of creep ruptured specimen of JLF-1 was lower than that of the as-tempered steel and the difference in hardness showed no significant change, irrespective of the maximum indentation load, i.e., the plastic zone diameter. This reduction in hardness seemed to be caused by the decrease in strength of block interior (matrix), because the block size showed almost no variation. On the other hand, the decrease in hardness of the rotor steel was strongly dependent on the plastic zone diameter. The creep ruptured specimen had 1∼1.5 GPa lower hardness than the as-tempered steel, except for the lowest maximum load of 1 mN where the decrease in hardness was estimated to be 0.4 GPa. At the maximum load of 1 mN, the plastic zone diameter was estimated to be around 1.9 μm and was smaller than the block size (2.2∼3 μm), that is, the effect of

  3. Exposure to radiation from the natural radioactivity in building materials

    International Nuclear Information System (INIS)

    Radiation exposure of members of the public can be increased appreciably by the use of building materials containing above-normal levels of natural radioactivity. This phenomenon has attracted attention in recent years, and in this review, an attempt is made to the quantify exposures incurred under various circumstances. The second section of the review is a general survey of those building materials, mostly industrial wastes, that have aroused interest in Member countries. The probability that environmental pressures may cause such wastes to be used more and more by building industries may lead to similar situations in the future. Other review material of a relevant nature is described in the third section. Primordial radionuclides only are considered here. They are: potassium-40 (K-40); radium-226 (Ra-226) and its decay products; the series headed by thorium-232 (Th-232). The important radiological consequences of the natural radioactivity in building materials are two-fold, irradiation of the body by gamma rays and irradiation of the lung tissues by radon-222 (Rn-222) decay products or daughters. These consequences cannot be explored quantitatively except in relation to the specific activities of the nuclides of interest, and the approach adopted in this review is to assess the consequences in terms of the incremental radiation exposures that would be incurred by occupants of substantial dwellings entirely constructed of materials with various specific activities or combinations thereof. Gamma rays are dealt with in the fourth section and radon daughters in the fifth

  4. Phase Change Materials for Thermal Regulation of Building Integrated Photovoltaics

    OpenAIRE

    Hassan, Ahmad, (Thesis)

    2010-01-01

    In outdoor deployed photovoltaics (PV), standard test conditions (STC) of 25 °C PV temperature, 1000 Wm-2 solar radiation intensity and 1.5 air-mass rarely prevail. PV temperature can rise 40-100 °C above STC inducing a power drop in crystalline silicon PV with a coefficient of -0.4 to -0.65 %/K above STC. Increased operating temperature also results in accelerated PV degradation due to cell delamination allowing moisture ingress. vConventional building integrated photovoltaics (BIPV) cooling...

  5. Alkaline degradation of organic materials contained in TRU wastes under repository conditions

    International Nuclear Information System (INIS)

    Alkaline degradation tests for 9 organic materials were conducted under the conditions of TRU waste disposal: anaerobic alkaline conditions. The tests were carried out at 90degC for 91 days. The sample materials for the tests were selected from the standpoint of constituent organic materials of TRU wastes. It has been found that cellulose and plastic solidified products are degraded relatively easily and that rubbers are difficult to degrade. It could be presumed that the alkaline degradation of organic materials occurs starting from the functional group in the material. Therefore, the degree of degradation difficulty is expected to be dependent on the kinds of functional group contained in the organic material. (author)

  6. 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.

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

    DEFF Research Database (Denmark)

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

    2015-01-01

    Biocides are common additives in building material. In-can and film preservatives in render and paint, as well as wood preservatives are used in order to protect façade materials from microbial spoilage. However, it is known that these compounds with fungicidal, bactericidal and algaecidal activity...... leach out of the material when it gets in contact with rainwater. While in city centers the total façade runoff drains on paved surfaces like streets and terraces and further into the sewer system, the runoff in residential areas drains to a certain amount to beds or the lawn surrounding the houses....... 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...

  8. Determination of Natural Radioactivity in Building Materials with Gamma Spectrometry

    International Nuclear Information System (INIS)

    In the setting of this work, the natural radioactivity of building materials used in Tunisia has been measured by gamma spectrometry. These products have been ground and dried at 100 degree for 12 h. Then, they have been homogenized, weighed and finally conditioned during 23 days in order to reach the radioactive equilibrium. The measures' results proved that all building materials studied except bauxite and the ESC clay, possess doses lower than the acceptable limit (1 mSv.an-1). However, the possibility of reinforcement of the natural radioactivity in some industry of building can exist. To insure that the cement, the most used in the world, don't present any radiological risk on the workers' health, a survey has been made in the factory - les Ciments de Bizerte - about its manufacture's process. The results of this survey showed that this product can be considered like a healthy product.

  9. 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.

  10. The release of lindane from contaminated building materials

    OpenAIRE

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

    2014-01-01

    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 s...

  11. COMPOSITION BUILDING MATERIALS ON THE BASIS OF MODIFIED LIQUID OLIGODIENES

    OpenAIRE

    D. E. Barabash

    2010-01-01

    The results of elaboration of efficient building composites on the basis of modified oligodienes are presented. The basic propositions on design of ma-terial formulations for different purposes with consideration for the particu-larities of their use are given. The ways of improvement of technology of composites preparation subject to proposed operation conditions are sug-gested.

  12. 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.

  13. Application of the Compliance Algorithms for Building Materials. Annex VI

    International Nuclear Information System (INIS)

    A method is presented in this Annex for calculating dose due to external gamma radiation from building materials on the basis of the approach of Markkanen. The results are given in tabular form as specific dose rates. This allows the most typical dose assessments to be made without computer calculations. Five examples of such assessments are given in this Annex. The method is based on calculating the dose rate for a rectangular building constructed of building material of uniform density and containing radionuclides of uniform activity concentration. The dose rate indoors is calculated by summing the separately calculated dose rates due to radionuclides in the walls, floor and ceiling of a room. The effects of doors and windows will lower the dose rate by only a minor amount and so for simplicity doors and windows are not considered in the calculation. The calculation covers situations in which the radionuclides are distributed in two layers of separate building materials with different densities and activity concentrations; for example, concrete walls covered with a thin layer of another material such as tiles

  14. New concrete materials technology for competitive house building

    OpenAIRE

    Peterson, Markus

    2003-01-01

    The research project aims at investigating the potential of new concrete materials technology (high performance concrete, HPC and self-compacting concete, SCC) for competitive design, production and function of structural frames of cast in-situ concrete in house building.

  15. 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}).

  16. Influence of temperature on strain monitoring of degradation in concrete containment buildings

    International Nuclear Information System (INIS)

    Concrete containment buildings (CCBs) are important safety structures in a nuclear power plant (NPP). The CCBs can be made of reinforced and post-tensioned (P-T) concrete. Post-tensioning concrete induces compressive stresses, which have to be overcome for the concrete to crack under tensile loads. However, post-tensioned CCBs may undergo pre-stressing losses as they age, which could affect their performance under accident conditions. CANDU 6 reactor buildings contain grouted post-tensioned tendons as the primary reinforcement. The grouting of the tendons makes direct monitoring of pre-stressing losses via lift-off testing impossible. Therefore, instruments have been installed on an existing reactor building to measure and monitor strains and stresses in the concrete and the deformation of the concrete structure to detect aging degradation and indirectly evaluate the pre-stressing losses. However, the instrumentation readings are affected by temporary volume changes in the concrete caused by the influence of environmental factors, particularly temperature, on concrete. In this work, the focus is on developing an understanding of the effect of temperature on the interpretation of instrumentation data from a reactor building. Vibrating Wire Strain Gauge (VWSG) data has been analysed. The influence of concrete coefficient of thermal expansion and temperature distribution within the reactor building walls, on VWSG data, is discussed based on the analysis of the available instrumentation data and available numerical simulation results. The present study demonstrates that temperature distribution within the containment concrete has a significant impact on the VWSG measurements and the coefficient of thermal expansion of concrete is an important factor in the correction of VWSG data for thermal strain. It is recommended that VWSG data obtained over small temperature variations be considered for interpretation to assess pre-stressing losses. (authors)

  17. Assessment of the radiological impact of selected building materials

    International Nuclear Information System (INIS)

    Naturally occurring radionuclides in building materials are a source of external and internal radiation exposure to essentially the entire Polish population. The programme of our studies met two main aspects on radioactivity of building materials: Gamma dose rate and radon or alpha potential energy concentration measurements in dwellings of various kinds of structure and materials in both industrial and rural districts of Poland. Gamma dose rate measurements were made in about 2200 dwellings and radon or alpha potential energy concentration measurements - in 750 dwellings. On the basis of these studies the annual effective dose equivalent to the Polish population due to gamma and alpha radiation indoors was estimated to be 0.39 mSv/a and 0.99 mSv/a, respectively. The contribution of external (from gamma) and internal (from alpha) radiation exposure due to naturally occurring radionuclides in building materials to the total radiation exposure of Polish population was assessed to be 3.6 per cent and 34.2 per cent, respectively. Measurements of about 1500 samples of various kinds of building materials and raw materials were made to determine radionuclide concentrations in them. The highest values were obtained in samples of phosphogypsum, fly ash and slag: potassium concentration ranges up to 36 pCi g-1 (a slag sample), radium - up to 17 pCi g-1 (a phosphogypsum sample) and thorium - up to 4 pCi g-1 (a phosphogypsum). On the basis of the results of our studies we came to the conclusion that it was necessary to work out a control system which could protect habitants against enhancement of indoor exposure to ionizing radiation

  18. Radiological dose assessment of naturally occurring radioactive materials in concrete building materials

    International Nuclear Information System (INIS)

    Previous studies have shown that the natural radioactivity contained in building materials have significantly influenced the dose rates in dwelling. Exposure to natural radiation in building has been of concerned since almost 80 % of our daily live are spend indoor. Thus, the aim of the study is to assess the radiological risk associated by natural radioactivity in soil based building materials to dwellers. A total of 13 Portland cement, 46 sand and 43 gravel samples obtained from manufacturers or bought directly from local hardware stores in Peninsular of Malaysia were analysed for their radioactivity concentrations. The activity concentrations of 226Ra, 232Th and 40K in the studied building materials samples were found to be in the range of 3.7-359.3, 2.0-370.8 and 10.3-1,949.5 Bq kg-1 respectively. The annual radiation dose rates (μSv year-1) received by dwellers were evaluated for 1 to 50 years of exposure using Resrad-Build Computer Code based on the activity concentration of 226Ra, 232Th and 40K found in the studied building material samples. The rooms modelling were based on the changing parameters of concrete wall thickness and the room dimensions. The annual radiation dose rates to dwellers were found to increase annually over a period of 50 years. The concrete thicknesses were found to have significantly influenced the dose rates in building. The self-absorption occurred when the concrete thickness was thicker than 0.4 m. Results of this study shows that the dose rates received by the dwellers of the building are proportional to the size of the room. In general the study concludes that concrete building materials; Portland cements, sands, and gravels in Peninsular of Malaysia does not pose radiological hazard to the building dwellers. (author)

  19. Damage Assessment Technologies for Prognostics and Proactive Management of Materials Degradation

    International Nuclear Information System (INIS)

    The Nuclear Regulatory Commission has undertaken a program to lay the groundwork for defining proactive actions to manage degradation of materials in light water reactors (LWRs). This paper discusses the U.S. Nuclear Regulatory Commission's Proactive Management of Materials Degradation (PMMD) program and its application to nuclear power plant structures, systems and components. The PMMD program is examining LWR component materials and the degradation phenomena that affect them. Of particular interest is how such phenomena can be monitored to predict degradation and prevent component failure. Some forms of degradation, such as stress corrosion cracking, are characterized by a long initiation time followed by a rapid growth phase. Monitoring such long-term degradation will require new NDE methods and measurement procedures. A critical analysis of all reactor components is required to determine if new inspection strategies are required to effectively manage slow degradation mechanisms that may lead to component failure. As reactor lifetimes are extended, degradation mechanisms previously considered too long-term to be of consequence (such as concrete and wiring insulation degradation) may become more important. This paper includes a review of techniques with potential for sensing and monitoring degradation in its early stages and will concisely explain the basic principles of PMMD and its relationship to in-service inspection, condition based maintenance, and advanced diagnostics and prognostics.

  20. Prevention of radioactive gas seeping into buildings through constructive materials

    International Nuclear Information System (INIS)

    Full text: One of possible method of realization of the terrorist acts is using gases and liquids, which easily permeate through the constructive materials of walls, floor, ceiling, roof, etc. into buildings by the capillary action of the pores. Toxic volatile organic compounds, organic and inorganic gases, radioactive elements, especially, which emits alpha particles can be used as the dangerous substances. Increased ventilation may help in removing the gases, but can actually increase the gases level by increasing the suction through the pores of concrete. If the gases and liquids are soluble in water and are easily volatilized from it, they can also get by groundwater up to underground structures and penetrate inside through opening and pores in concrete or pushed by hydrostatic pressure. The purpose of this work is creating a method to reduce concentration of toxic and radioactive gases in homes, buildings, underground buildings, tunnels, hangars, garages, bomb shelters, etc. The most effective method to prevent penetration of radionuclides into premises of buildings and underground structures through walls, roofs, floors is using special chemicals, which seal micropores inside the construction materials against gases. Worked out chemicals which consist of blend of polymeric compounds are described in the paper. Radioactive gases permeability in constructive materials after treatment by chemicals was studied. Influence of types of cement, sand and gypsum, preliminary treatment by different chemicals, different types of polymeric compounds, time between treatments, moisture of materials, time between preparation of chemicals and treatment of materials (aging of chemicals), time between treatment of concrete and testing (aging of treated concrete) were examined. Experiments have shown that our method allows reducing the coefficient of gas permeability 200 - 400 times

  1. 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}).

  2. Natural radioactivity and indoor radiation measurements in buildings and building materials in Gobichettipalayam town

    International Nuclear Information System (INIS)

    Samples of natural and manufactured building materials used by the people of Gobichettipalayam town have been analyzed for 226Ra, 232Th and 40K using gamma-ray spectrometry. Radium equivalent activity of the materials has been measured using the formula given by OECD and the geometric mean value of sand, clay and cements are found to be 53.53 Bq x kg-1, 89.09 Bq x kg-1 and 72.25 Bq x kg-1, respectively. The radium equivalent activities obtained in the building materials are all well below the acceptable limit. The indoor gamma-dose has been measured using thermoluminescence dosimeters and it was found in the range of 1051.2-3946.0 μGy/year. The annual effective indoor gamma radiation dose to the people of Gobichettipalayam town has been found to be 0.8 mSv/y. (author)

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

    OpenAIRE

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

    2015-01-01

    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 mode...

  4. Natural radioactivity in building materials and phosphate fertilizer

    International Nuclear Information System (INIS)

    Construction industry is one of the most thriving industries in Kerala these days. The objective of the present study is to understand the various radionuclides present in some of the building materials used for construction of buildings in Kerala. The inhabitants as well as the construction workers of the building will be the suffering group if these materials are highly radioactive. The activity concentrations of 226Ra, 232Th and 40K measured in the different samples of building analysed is found to be greater than the values given in the references cited in the literature. The outdoor absorbed dose rate values and annual effective dose values were also determined. A newspaper reported recently that grains like rice and wheat are being transported to the ware houses of Food Corporation of India in Kerala from other states in the same wagon in which cement and fertilizers were transported. This news motivated us to analyse one fertilizer sample also for radioactivity. The activity concentrations of different radionuclides in the phosphate fertilizers, commonly used by farmers in Kerala is reported. (author)

  5. Conjugate modelling of convective drying phenomena in porous building materials

    International Nuclear Information System (INIS)

    Moisture storage and the associated heat and moisture transport in buildings have a large impact on the building envelope durability, the energy consumption in buildings and the indoor climate. Nowadays HAM (Heat, Air and Moisture transport) models are widely used to simulate and predict the effect of these transport phenomena in detail. Recently these HAM models are being coupled to CFD (Computational Fluid Dynamics) to study the moisture exchange between air and porous materials on a local scale (microclimates). The objective of this research is to develop such a model to study drying phenomena. In this paper the emphasis lies on the modelling of convective drying of porous building materials. An important aspect for the correct modelling of convective drying is the way the air boundary is implemented. A short literature review reveals that different modelling approaches can be used. This paper gives a short overview of the state of the art in conjugate heat and mass transport modelling for convective drying. In this review shortcomings of currently applied modelling approaches are highlighted. Finally the newly developed model is used to simulate the convective drying of a sample of ceramic brick. These simulations were then compared with measurements from literature. A good agreement was found.

  6. 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.

  7. 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

  8. Regularities of radiation defects build up on oxide materials surface

    International Nuclear Information System (INIS)

    Analysis of experimental data by radiation defects study on different oxide elements (silicon, beryllium, aluminium, rare earth elements) irradiated by the photo-, gamma-, neutron-, alpha- radiation, protons and helium ions show, that gas adsorption process on the surface centers and radiation defects build up in metal oxide correlated between themselves. These processes were described by the equivalent kinetic equations for analysis of radiation defects build up in the different metal oxides. It was revealed in the result of the analysis: number of radiation defects are droningly increasing up to limit value with the treatment temperature growth. Constant of radicals death at ionizing radiation increases as well. Amount of surface defects in different oxides defining absorbing activity of these materials looks as: silicon oxide→beryllium oxide→aluminium oxide. So it was found, that most optimal material for absorbing system preparation is silicon oxide by it power intensity and berylium oxide by it adsorption efficiency

  9. 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.

  10. Histological and molecular evaluation of iron as degradable medical implant material in a murine animal model.

    OpenAIRE

    Mueller, Peter P; Arnold, Sylvia; Badar, Muhammad; Bormann, Dirk; Bach, Friedrich-Wilhelm; Drynda, Andreas; Meyer-Lindenberg, Andrea; Hauser, Hansjörg; Peuster, Matthias

    2012-01-01

    A small animal model was established to evaluate the potential of iron as a degradable implant material. After insertion into the tail of mice, the implants gradually degraded over a clinically relevant time period of several months. Histological analysis and gene expression data from whole-genome microarray analyses indicated a limited inflammatory reaction. No evidence of cellular responses to excess iron ions was detected, suggesting that the iron degradation products were metabolically in...

  11. Changes in morphology of starch-based prothestic thermoplastic material during enzymatic degradation

    OpenAIRE

    Araújo, M. Alberta; Cunha, A.M.; Mota, M

    2004-01-01

    This work evaluates the structural changes of an interpenetrated starch thermoplastic blend withstanding different enzymatic -amylase degradation periods (up to 200 days), and establishes the relationships between the kinetics degradation rate and the structure of the material. It characterises the different stages of the enzymatic degradation process on starch/ethylenevinyl-alcohol blends, based on the attack of the connected starch domains that can be accessed by the enzymatic solution. The...

  12. Evaporation from porous building materials and its cooling potential

    OpenAIRE

    Gonçalves, Teresa; Brito, Vânia; Vidigal, Filipa; Matias, Luís; Faria, Paulina

    2015-01-01

    Evaporative cooling is a traditional strategy to improve summer comfort, which has gained renewed relevance in the context of the transition to a greener economy. Here, the potential for evaporative cooling of two common porous building materials, natural stone and ceramic brick, was evaluated. The work has relevance also to the protection of built heritage becauseevaporation underlies the problems of dampness and salt crystallization, which are so harmful and frequent in this heritage. It wa...

  13. Oriented strand board: new material for building construction

    International Nuclear Information System (INIS)

    The paper will attempt to show the suitability and competitiveness of oriented strand board (OSB) in building construction. One important factor underlining the success of this product is the availability of the wood raw material. Plantation timbers such as rubberwood, paraserianthes falcataria, acacia crassicarpa, A. auriculiformis and A. mangium have been identified as the major source of this industry. We will focus on the domestic market as well as export market especially on the Asia Pacific region

  14. 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

    In this study, the ability to produce mycotoxins during growth on artificially infested building materials was investigated for Penicillium chrysogenum, Pen. polonicum, Pen. brevicompactum, Chaetomium spp., Aspergillus ustus, Asp. niger, Ulocladium spp., Alternaria spp., and Paecilomyces spp., all......., alternariol and alternariol monomethyl ether were detected. From Ulocladium spp., Paecilomyces spp., and Asp. ustus no known mycotoxins were detected, although the latter two are known mycotoxin producers. Asp. niger produced several naphtho-gamma-pyrones and tetra-cyclic compounds. All investigated species...

  15. Measurement of Moisture Storage Parameters of Building Materials

    OpenAIRE

    M. Jiřičková; Černý, R.; P. Rovnaníková

    2003-01-01

    The moisture storage parameters of three different building materials: calcium silicate, ceramic brick and autoclaved aerated concrete, are determined in the hygroscopic range and overhygroscopic range. Measured sorption isotherms and moisture retention curves are then combined into moisture storage functions using the Kelvin equation. A comparison of measured results with global characteristics of the pore space obtained by mercury intrusion porosimetry shows a reasonable agreement; the medi...

  16. The use of radioactive residues as building material

    International Nuclear Information System (INIS)

    The patent describes the use of radioactive residues consisting of metal and/or concrete, particularly in the form of removed or dismantled radioactive core plant, as building material for shielding in nuclear technology, also in the form of equipment having a shielding function. The method used ensures that the specific radioactivity equivalent to cobalt 60 is below 100 Bq/gram. (orig./PW)

  17. Permeability of some building construction material for radon diffusion

    International Nuclear Information System (INIS)

    In the present work, the radon diffusion coefficient and diffusion lengths for some building construction materials viz: soil, sand, cement, fly ash have been calculated. Radon diffusion and transport through different media is a complex process and is affected by several factors. The diffusion of the radon through the ground is a complex process and is related to the porosity, permeability, which is dependent on grain size distribution, degree of compaction and the water content of the soil. The apparatus designed for the study of radon diffusion through different building construction materials consists of a hollow plastic cylinder of inner diameter 25 cm and length 50 cm deployed vertically. The radon source covered with latex membrane is fixed at the bottom of the cylinder in the cavity. Open-ended cylindrical tubes of diameter 1.5 cm and of length 15 and 25 cm are installed in hollow plastic cylinder. The top end of each diffusion tube holds LR-115 type-II plastic detector such that its sensitive side always faces the source of radon. The building construction materials under study in the pulverized form are filled in diffusion tubes and the system is left undisturbed for a period of 30 days. The detectors are chemically etched in NaOH solution. The alpha tracks are counted using an optical Olympus microscope

  18. 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

  19. 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.

  20. Photon attenuation coefficients and shielding effects of Jordanian building materials

    International Nuclear Information System (INIS)

    Highlights: • The mass attenuation coefficients were calculated for the 50–3000 keV gamma-ray energy. • Values obtained were used to evaluate the protection provided by different building. • Significant benefits could be achieved in using the basement and lower floors. - Abstract: The present study was conducted to investigate the attenuation properties of building materials commonly used in Jordan. The photon interactions with materials of interest were discussed in terms of mass attenuation coefficients for the 50–3000 keV gamma-ray energy range. The linear attenuation coefficients were measured at several photon energies using a NaI(Tl) detector and a narrow beam geometry technique. The values obtained were used to evaluate the shielding provided by different construction styles, against a hypothetical release of radioactive material as a function of the photon energy of the released material. The results obtained revealed that wall mass thickness and material chemical compositions, of the investigated construction styles, are crucial factors in shielding against radiation. An exterior wall with mass thickness of 52 g/cm2, attenuates more than 98% of the incident photons of energy 662 keV. Moreover, the addition of a high density limestone layer to the face of a concrete wall, has increased its shielding effectiveness by about 10%

  1. LABORATORY SYSTEM FOR INVESTIGATION OF FATIGUE DEGRADATION IN FERROMAGNETIC MATERIALS AND EXAMPLES OF ITS IMPLEMENTATION

    Directory of Open Access Journals (Sweden)

    V. N. Busko

    2012-01-01

    Full Text Available Shows the block diagram of the laboratory system for investigation of fatigue degradation in ferromagnetic materials by method of magnetic noise. Describes the principle operation of the system, given the practical results its using in assessment of the degree fatigue degradation in ferromagnetic structural steels and alloys on the basis of cyclic testing and measuring the intensity of the magnetic noise.

  2. RNA as a stable polymer to build controllable and defined nanostructures for material and biomedical applications

    Science.gov (United States)

    Li, Hui; Lee, Taek; Dziubla, Thomas; Pi, Fengmei; Guo, Sijin; Xu, Jing; Li, Chan; Haque, Farzin; Liang, Xing-Jie; Guo, Peixuan

    2015-01-01

    Summary The value of polymers is manifested in their vital use as building blocks in material and life sciences. Ribonucleic acid (RNA) is a polynucleic acid, but its polymeric nature in materials and technological applications is often overlooked due to an impression that RNA is seemingly unstable. Recent findings that certain modifications can make RNA resistant to RNase degradation while retaining its authentic folding property and biological function, and the discovery of ultra-thermostable RNA motifs have adequately addressed the concerns of RNA unstability. RNA can serve as a unique polymeric material to build varieties of nanostructures including nanoparticles, polygons, arrays, bundles, membrane, and microsponges that have potential applications in biomedical and material sciences. Since 2005, more than a thousand publications on RNA nanostructures have been published in diverse fields, indicating a remarkable increase of interest in the emerging field of RNA nanotechnology. In this review, we aim to: delineate the physical and chemical properties of polymers that can be applied to RNA; introduce the unique properties of RNA as a polymer; review the current methods for the construction of RNA nanostructures; describe its applications in material, biomedical and computer sciences; and, discuss the challenges and future prospects in this field. PMID:26770259

  3. Natural radioactivity of building materials used in Malaysia

    International Nuclear Information System (INIS)

    A study has been carried out to determine the natural radioactive content of building materials used in Malaysia. The materials analysed include both old and new clay bricks, cement bricks, mortar, cement, sands, ceramic tiles and gypsum. Samples of the first three materials were collected from the 12 states of the Malay Peninsula. Radium-226 (from the U-238 series) and Ra-228 (from the Th-232 series), these both representing naturally occurring radionuclides, were analysed using high-resolution HpGe gamma spectrometers. The results of our investigations showed that some old clay bricks contain high levels (at more than 5 times the normal soil concentration) of natural radionuclides, with maximum concentrations of 590 Bq/kg and 480 Bq/kg for respectively Ra-226 and Ra-228. The reasons behind this finding were not clearly understood. As there are people living in old buildings, i.e. built using old clay bricks, there is a possibility that they are being exposed to significant radiation doses. However, there proved to be no significant overall difference between old and new clay bricks in terms of the natural radioactivity levels determined, at a 95% confidence level. The overall mean concentrations of Ra-226 and Ra-228 observed in Malaysian clay bricks were respectively 118 ± 58 Bq/kg and 120 ± 42 Bq/kg. The radioactive content of other materials was found to be not much different from that to be determined in normal soil from Malaysia. The data obtained can be used as a basis for reaching decisions on the regulatory limits for radioactivity levels in building materials in Malaysia. (orig.)

  4. On the Influence of the Sample Absorptivity when Studying the Thermal Degradation of Materials

    Directory of Open Access Journals (Sweden)

    Pascal Boulet

    2015-08-01

    Full Text Available The change in absorptivity during the degradation process of materials is discussed, and its influence as one of the involved parameters in the degradation models is studied. Three materials with very different behaviors are used for the demonstration of its role: a carbon composite material, which is opaque, almost grey, a plywood slab, which is opaque and spectral-dependent and a clear PMMA slab, which is semitransparent. Data are analyzed for virgin and degraded materials at different steps of thermal degradation. It is seen that absorptivity and emissivity often reach high values in the range of 0.90–0.95 with a near-grey behavior after significant thermal aggression, but depending on the materials of interest, some significant evolution may be first observed, especially during the early stages of the degradation. Supplementary inaccuracy can come from the heterogeneity of the incident flux on the slab. As a whole, discrepancies up to 20% can be observed on the absorbed flux depending on the degradation time, mainly because of the spectral variations of the absorption and up to 10% more, depending on the position on the slab. Simple models with a constant and unique value of absorptivity may then lead to inaccuracies in the evaluation of the radiative flux absorption, with possible consequences on the pyrolysis analysis, especially for properties related to the early step of the degradation process, like the time to ignition, for example.

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

    Science.gov (United States)

    Frechet, Jean M. J.; Standley, Stephany M.; Jain, Rachna; Lee, Cameron C.

    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.

  6. 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. PMID:20167403

  7. Radon exhalation from building materials for decorative use

    International Nuclear Information System (INIS)

    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

    International Nuclear Information System (INIS)

    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. (authors)

  9. 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

  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. Radionuclide contents in building materials used in Hong Kong

    International Nuclear Information System (INIS)

    The radionuclide contents of conventional natural raw building materials, coal ash and slag, and finished building products have been determined using gamma-ray spectrometry. Results of brick measurements in their original geometry and in crushed form are compared. The radioactive concentrations in cement and sand, mostly imported from China, are among the lowest measured. However, due to the high radioactivity of aggregates, composed of granite mainly extracted locally, the mean Ra equivalent activity of concrete is high compared with that in some countries. The radioactivity levels of coal ash and slag in Hong Kong are about the average values in other countries. The incorporation of coal ash and slag in ordinary concrete does not alter the radioactivity significantly

  12. Spectral Signatures of Surface Materials in Pig Buildings

    DEFF Research Database (Denmark)

    Zhang, GuoQiang; Strøm, Jan; Blanke, Mogens; Braithwaite, Ian D.

    2006-01-01

    Manual cleaning of pig production buildings based on high-pressure water cleaners is unappealing to workers, because it is tedious and health threatening. To replace manual cleaning, a few cleaning robots have been commercialised. With no cleanliness sensor available, the operation of these robots...... is to follow a cleaning procedure initially defined by the operator. Experience shows that the performance of such robots is poor regarding effectiveness of cleaning and utilisation of water. The development of an intelligent cleanliness sensor for robotic cleaning is thus crucial in order to...... optimise the cleaning process and to minimise the amount of water and electricity consumed. This research is aimed at utilising a spectral imaging method for cleanliness detection. Consequently, information on the reflectance of building materials and contamination in different spectral ranges is important...

  13. 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.

  14. Natural radioactivity in Slovak construction materials and the indoor dose rate from building materials

    International Nuclear Information System (INIS)

    For keeping the population exposure al low as reasonably achievable (recommended by the Slovak regulations), the radioactive content of primordial radionuclides in building materials and products have not to exceed 370 Bq kg-1 of radium equivalent activity and 120 Bq kg-1 of 226Ra. Samples of building materials (cement, stone, fly-ash, light concrete, slag, dross, sand dolomite. etc.) user for construction of the residential buildings were collected, milled and screened with 2-3 cm sieve. After drying, the samples were stored in 450 cm3 sealed polyethylene containers for a 30 day period. All samples were measured in a 4 π geometry usually for 60,000 seconds. Measurements of 226Ra, 232Th and 40K concentrations were carried out by high resolution gamma-ray spectrometry. The primordial radionuclides 226 and 232Th were assessed through their progeny photo-peaks 214Bi (609 keV), 214Pb (295 keV, 351 keV) 228Ac (338 keV, 911 keV) and 212Pb (238 keV). The specific activity of both nuclides has been determined as weighted average of their photo-peaks. 40K was measured directly via its 1460 keV peak. Until now, about 600 samples of building materials have been measured. The obtained radium equivalent activity in various types of building materials and mean annual effective doses of gamma radiation are presented. (J.K.)

  15. 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

  16. Potential damage to modern building materials from 21st century air pollution.

    Science.gov (United States)

    Brimblecombe, Peter; Grossi, Carlota Maria

    2010-01-01

    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. PMID:20098955

  17. 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.

  18. Fungal accumulation of metals from building materials during brown rot wood decay.

    Science.gov (United States)

    Hastrup, Anne Christine Steenkjær; Jensen, Bo; Jellison, Jody

    2014-08-01

    This study analyzes the accumulation and translocation of metal ions in wood during the degradation performed by one strain of each of the three brown rot fungi; Serpula lacrymans, Meruliporia incrassata and Coniophora puteana. These fungi species are inhabitants of the built environment where the prevention and understanding of fungal decay is of high priority. This study focuses on the influence of various building materials in relation to fungal growth and metal uptake. Changes in the concentration of iron, manganese, calcium and copper ions in the decayed wood were analyzed by induced coupled plasma spectroscopy and related to wood weight loss and oxalic acid accumulation. Metal transport into the fungal inoculated wood was found to be dependent on the individual strain/species. The S. lacrymans strain caused a significant increase in total iron whereas the concentration of copper ions in the wood appeared decreased after 10 weeks of decay. Wood inoculated with the M. incrassata isolate showed the contrary tendency with high copper accumulation and low iron increase despite similar weight losses for the two strains. However, significantly lower oxalic acid accumulation was recorded in M. incrassata degraded wood. The addition of a building material resulted in increased weight loss in wood degraded by C. puteana in the soil-block test; however, this could not be directly linked specifically to the accumulation of any of the four metals recorded. The accumulation of oxalic acid seemed to influence the iron uptake. The study assessing the influence of the presence of soil and glass in the soil-block test revealed that soil contributed the majority of the metals for uptake by the fungi and contributed to increased weight loss. The varying uptake observed among the three brown rot fungi strains toward the four metals analyzed may be related to the specific non-enzymatic and enzymatic properties including bio-chelators employed by each of the species during wood

  19. 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.

  20. Device for storage of radioactive material in a building with heat pipes set in the building wall

    International Nuclear Information System (INIS)

    When storing radio-active material in a building, safe and sufficient heat removal must always be guaranteed. On the other hand, the building should be safely closed to the environment. The invention makes it possible to ensure, for such a building with heat pipes set in the building wall, that it is possible to use at least part of the heat generated in the building without limiting the removal of heat. Cooling sleeves are fitted to the heat pipes near the building wall for this purpose, where a cooling circuit with a circulating coolant is connected to the cooling sleeves. (orig.)

  1. 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)

  2. Processing the right building materials with fly ash content

    Energy Technology Data Exchange (ETDEWEB)

    Oostendorp, F.E. [EZH (Netherlands)

    1997-12-31

    The use of power station ash and fly ash in construction in the Netherlands is described. Fly ash production by the industry is high, but practically all is used as a building material. The fly ash is used in producing cement, artificial gravel, as an asphalt filter, in concrete, and for special applications. Two processes are used to turn fly ash into artificial gravel. The LYTAG process mixes the ash with pulverized coal and water to form pellets, then ignites the pellets resulting in their sintering. The Aerdelite process mixes dry ash with lime, then blows steam through at 85{degree}C, resulting in a hardening reaction.

  3. Measurement of Moisture Storage Parameters of Building Materials

    Directory of Open Access Journals (Sweden)

    M. Jiřičková

    2003-01-01

    Full Text Available The moisture storage parameters of three different building materials: calcium silicate, ceramic brick and autoclaved aerated concrete, are determined in the hygroscopic range and overhygroscopic range. Measured sorption isotherms and moisture retention curves are then combined into moisture storage functions using the Kelvin equation. A comparison of measured results with global characteristics of the pore space obtained by mercury intrusion porosimetry shows a reasonable agreement; the median pore radii by volume are well within the interval given by the beginning and the end of the characteristic steep parts of the moisture retention curves.

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

    International Nuclear Information System (INIS)

    Soil based building materials known to contain various amounts of natural radionuclide mainly 238U and 232Th series and 40K. 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 222Radon and its progenies which arise from the decay of 226Ra. 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−3, 192 Bq m−3, 176 Bq m−3 and 28 Bq m−3, respectively. The result indicates that the radon concentration in the studied building materials have more than 100 Bq m−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−1, 4.85 mSv y−1, 4.44 mSv y−1 and 0.72 mSv y−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−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

  5. A novel method for on-orbit measurement of space materials degradation

    International Nuclear Information System (INIS)

    The low Earth orbit (LEO) environment is considered hazardous to spacecraft, resulting in materials degradation. Currently, in order to evaluate the degradation of materials in LEO, a retrieval of space exposed samples is required. In this study, a novel approach is proposed to evaluate degradation of materials in LEO without the need of retrieval. The method is utilizing photovoltaic cells (PVCs), an existing component onboard of any satellite. The PVCs are coated by various materials which are sensitive to different LEO constituents, such as atomic oxygen (AO) or ultra-violet (UV) radiation. The method's acronym is ORMADD (on-ORbit MAterials Degradation Detector). The ORMADD's principle of operation is based on measuring the PVC output power which depends on the cell coating material's optical transmission. Erosion of the coating by AO or coloring due to UV radiation affects its optical transmission and, accordingly, the PVC output. The ORMADD performance was tested using different coatings, such as polyimide and amorphous carbon (sensitive to AO), and siloxane based coating which is sensitive to UV radiation. The proposed ORMADD reveals sensitivity to different LEO components and can be used either as material degradation detector or as an AO monitor.

  6. Natural radioactivity in common building construction and radiation shielding materials

    Science.gov (United States)

    Sonkawade, R. G.; Kant, K.; Muralithar, S.; Kumar, R.; Ramola, R. C.

    Commonly used building construction materials, radiation shielding bricks, hematite aggregate and other materials have been analyzed for the activity concentration of the natural radionuclides, namely 238U, 232Th and 40K, besides the radon exhalation rates. The activity concentration for 238U, 232Th and 40K varies from 29±1 to 98±4 Bq kg -1, 20±2 to 112±2.8 Bq kg -1, and 200±8 to 1908±15.6 Bq kg -1, respectively, in various materials studied in the present work. Radon activity in the various samples varies from 190±11 to 313±14 Bq m -3, the mass exhalation rate for radon varies from 1.05±0.07 to 1.92±0.09 mBq kg -1 h -1 and surface exhalation rate varies from 9.0±0.30 to 19.8±22 mBq m -2 h -1 for materials under investigation. The activity concentrations of uranium, thorium and potassium and radon exhalation rates vary from material to material. Thorium and potassium activity in the granite materials is higher, followed by radiation shielding material compared to other common construction materials. Uranium activity concentration is higher in cement as compared to radiation shielding material and other common construction materials. The absorbed dose varies from 23 to 185 nGy h -1 and the indoor annual effective dose varies from 0.11 to 0.91 mSv. The outdoor annual effective dose varies from 0.03 to 0.23 mSv. The absorbed dose and the effective dose equivalent are found to be higher in the granite, followed by radiation shielding material and other common construction materials. In all the samples, the activity concentration of 238U, 232Th and 40K is found below the permissible levels. A strong correlation coefficient has been observed between radon activity and surface exhalation rate (correlation coefficient=0.899).

  7. Study on reactor building structure using ultrahigh strength materials, 5

    International Nuclear Information System (INIS)

    Reinforced concrete (RC) shear walls are the main members of a reactor building for the aseismatic design. The characteristics of nonlinear behavior have been clarified by a number of experimental studies, and the reliability of the nonlinear analysis of RC structures by FEM has been improved by the studies on the constitutive equation for concrete and the simulation analysis of test results. However, the characteristics of the RC shear walls made of ultrahigh strength materials have not been sufficiently studied. In this paper, the nonlinear analysis of the RC shear walls made of ultrahigh strength materials is discussed. Based on the results of a series of the material test and pure shear test on ultrahigh strength materials, the simulation analysis of bending shear test was performed by three-dimensional nonlinear FEM. The specimens used for the bending shear test were single story, single span model shear walls. The analytical method, the modeling of concrete and reinforcing bars, the properties of the materials used and the results of analysis on the effects of concrete strength and the quantity and grade of bars are reported. (K.I.)

  8. Radioactivity in building materials used in and around Dhaka City

    International Nuclear Information System (INIS)

    The activity levels of 226Ra, 232Th and 40K were determined using gamma-ray spectroscopy in different commercial brands of cement, sand and hollow concrete bricks, which were collected from the building material suppliers of Dhaka City. The activity concentrations in the samples were found to be somewhat higher than in other countries. An effort has been made to assess the radiation hazard associated with these materials by determining the gamma activity concentration index I. It was found that the value of I for all the samples was ≤2, which indicates that the gamma dose contribution was not more than 0.3 mSv y-1. The samples considered were safe for use in the construction of urban dwellings in Bangladesh and do not pose any significant source of radiation hazard. (authors)

  9. Weld repair of helium degraded reactor vessel material

    International Nuclear Information System (INIS)

    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

  10. Reductive degradation of the new explosive material FOX-7

    Czech Academy of Sciences Publication Activity Database

    Šimková, Ludmila; Klíma, Jiří; Urban, Jiří; Ludvík, Jiří

    Herceg Novi: Materials Research Society of Serbia , 2012. s. 86. [Annual Conference YUCOMAT 2012 /14./. 03.09.2012-07.09.2012, Herceg Novi] R&D Projects: GA ČR GAP206/11/0727 Institutional support: RVO:61388955 Keywords : FOX-7 * electrochemistry

  11. Natural radioactivity measurements in some Indian building materials

    International Nuclear Information System (INIS)

    The present work deals with the radioactivity measurements of some Indian building materials using gamma ray spectrometry. The activity concentration obtained for 226Ra, 232Th and 40K ranged from 8.3 to 88.47, 8.45 to 95.29 and 23.43 to 155.46 Bq kg-1, with the mean values of 42.57, 34.85 and 63.25 Bq kg-1 respectively. To assess the radiological hazard of the natural radioactivity in the samples, the radium equivalent activity the absorbed dose rate and the external hazard index were also calculated. The study yields an annual effective dose equivalent in the range of 0.6 to 11.73 x 10-5 Sv with a mean value of 5.77 x 10-5 Sv. The results suggest that the use of such building materials in the construction of domestic dwellings or workplaces in India is unlikely to give rise to any significant radiation exposure to the occupants. The uranium calculated using fission track registration technique and the values ranged from 0.69 to 2.28 ppm. (author)

  12. 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. PMID:25739840

  13. Attitudinal effects of degrading themes and sexual explicitness in video materials.

    Science.gov (United States)

    Golde, J A; Strassberg, D S; Turner, C M; Lowe, K

    2000-07-01

    This study examined the independent and interactive effects of sexual explicitness and degrading themes toward women on mens' attitudes following exposure to video presentations of male-female interactions. Subjects were 83 male college students who viewed video vignettes under one of four stimulus conditions: (a) sexually explicit/degrading, (b) sexually explicit/nondegrading, (c) nonexplicit/degrading, and (d) nonexplicit/nondegrading. Results revealed that men exposed to degrading material, regardless of explicitness, were significantly more likely to express attitudes supportive of rape, while explicitness had no significant main or interactive effect on these attitudes. Further, the interaction of explicitness with degradation was found to impact scores on a measure of sexual callousness. Theoretical and clinical implications of these findings are discussed. PMID:10904993

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

    OpenAIRE

    Andersen, Birgitte; Jens C Frisvad; Søndergaard, Ib; Rasmussen, Ib S.; Larsen, Lisbeth S.

    2011-01-01

    Fungal growth in damp or water-damaged buildings worldwide is an increasing problem, which has adverse effects on both the occupants and the buildings. Air sampling alone in moldy buildings does not reveal the full diversity of fungal species growing on building materials. One aim of this study was to estimate the qualitative and quantitative diversity of fungi growing on damp or water-damaged building materials. Another was to determine if associations exist between the most commonly found f...

  15. Degradation mode surveys of high performance candidate container materials

    Energy Technology Data Exchange (ETDEWEB)

    Gdowski, G.E.; McCright, R.D.

    1990-12-01

    Corrosion resistant materials are being considered for the metallic barrier of the Yucca Mountain Project`s high-level radioactive waste disposal containers. Nickel-chromium-molybdenum alloys and titanium alloys have good corrosion resistance properties and are considered good candidates for the metallic barrier. The localized corrosion phenomena, pitting and crevice corrosion, are considered as potentially limiting for the barrier lifetime. An understanding of the mechanisms of localized corrosion and of how various parameters affect it will be necessary for adequate performance assessment of candidate container materials. Examples of some of the concerns involving localized corrosion are discussed. The effects of various parameters, such as temperature and concentration of halide species, on localized corrosion are given. In addition, concerns about aging of the protective oxide layer in the expected service temperature range (50 to 250{degree}C) are presented. Also some mechanistic considerations of localized corrosion are given. 45 refs., 1 tab.

  16. Degradation mode surveys of high performance candidate container materials

    International Nuclear Information System (INIS)

    Corrosion resistant materials are being considered for the metallic barrier of the Yucca Mountain Project's high-level radioactive waste disposal containers. Nickel-chromium-molybdenum alloys and titanium alloys have good corrosion resistance properties and are considered good candidates for the metallic barrier. The localized corrosion phenomena, pitting and crevice corrosion, are considered as potentially limiting for the barrier lifetime. An understanding of the mechanisms of localized corrosion and of how various parameters affect it will be necessary for adequate performance assessment of candidate container materials. Examples of some of the concerns involving localized corrosion are discussed. The effects of various parameters, such as temperature and concentration of halide species, on localized corrosion are given. In addition, concerns about aging of the protective oxide layer in the expected service temperature range (50 to 250 degree C) are presented. Also some mechanistic considerations of localized corrosion are given. 45 refs., 1 tab

  17. Techniques used for limiting degradation products of polymeric materials for use in the space environment

    Science.gov (United States)

    Vest, C. E.; Park, J. J.

    1978-01-01

    Techniques are discussed for limiting or controlling the degradation products (outgassing) of polymeric materials in the space environment. One technique, now ASTM E-595-77, is used to screen out those materials which lose greater than 1% Total Mass Loss when in vacuum for 24 hours at 125 C and which have more than 0.10% Collected Volatile Condensable Materials condensing on a collector surface at 25 C. Examples of silicone materials which are high and low in outgassing are given. The numerous mechanical motions in spacecraft experiments require liquid lubricants which also might degrade in space. Labyrinth seals and barrier films are utilized to limit the degradation of or from these lubricants. A recoverable in-flight experiment has been proposed for making definitive measurements of how effective these techniques are in limiting the amounts and escape paths of outgassed molecules.

  18. Proto pectin degradation of raw material by the acid hydrolysis

    International Nuclear Information System (INIS)

    The article presents results of hydrolysis proto pectin apples, an orange and a basket of sunflower depending on ph a solution. The reaction products are divided into three fractions conditionally named as micro gel, pectin substances and oligosaccharide. It was shown that the high-quality pectin extracted from orange, but high percentage of carboxylic group in the sunflower pectin allow it to by used as a drug delivery materials

  19. COMPOSITION AND METHOD FOR DEGRADATION OF KERATINACEOUS MATERIALS

    DEFF Research Database (Denmark)

    2015-01-01

    materials (such as e.g. feather and pig bristles). (FR)L'invention concerne une composition dégradant la kératine qui comprend au moins deux différentes kératinases actives isolées issues d'au moins deux familles de protéases MEROPS différentes, au moins une sérine endo-kératinase active appartenant à la...

  20. 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.

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

    International Nuclear Information System (INIS)

    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

  2. Preliminary experimental studies on the chemical and radiation degradation of combustible plutonium contaminated material

    International Nuclear Information System (INIS)

    The chemical and radiation degradation of combustible plutonium contaminated material (PCM) in a cement matrix has been investigated. Experimental studies have been carried out to establish the influence of any water soluble chemical and radiation degradation products on the solubility of plutonium at high pHs. The influence of complexing agents (e.g. EDTA, citric acid), which may be present in wastes, on plutonium solubility has been assessed. The extent of sorption on cement in the presence of organic degradation products has been measured. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

    Fukushima, Tatsuya; Yamamoto, Junichi; Fukuchi, Masashi; Kaji, Hironori, E-mail: kaji@scl.kyoto-u.ac.jp [Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011 (Japan); Hirata, Shuzo; Jung, Heo Hyo; Adachi, Chihaya [Center for Organic Photonics and Electronics Research (OPERA), Kyusyu University, 744 Motooka, Nishi, Fukuoka 819-0395 (Japan); Hirata, Osamu; Shibano, Yuki [Nissan Chemical Industries, LTD, 722-1 Tsuboi, Funabashi 274-8507 (Japan)

    2015-08-15

    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.

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

    OpenAIRE

    Magdalena Vaverková; Dana Adamcová; Jan Zloch

    2014-01-01

    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 ca...

  5. DEVELOPMENT OF IMPORT-SUBSTITUTING TECHNOLOGIES FOR BUILDING MATERIAL PRODUCTION

    Directory of Open Access Journals (Sweden)

    N. I. Berezovsky

    2015-01-01

    Full Text Available The paper presents results of investigations on rational usage of mineral resources. In particular, it has shown the possibility to increase a period of raw material serviceability and its application for production of building products depending on chemical and mineralogical composition of the waste. Analysis of the executed investigations shows that import substitution of anthracite, lignite and black coal for local fuels (milled peat and its sub-standard product is possible in the production technology of porous building materials.A mathematical model for drying process has been developed in the paper. Technology for thermal performance of a sintering machine with calculation of its length at the given pallet speed has been proposed on the basis of the developed model. Once-through circulation of flue gases and heated materials is the main specific feature of belt sintering machines being used in production. In such a case the whole drying process can be divided into two periods: a period of constant drying rate and a period of falling drying rate. Calculations have shown that the drying rate depends on moisture content but it does not depend on heat exchange Bio-criteria, however, heating rate is a function of temperature and Biq. A mechanism of moisture transfer using various drying methods is the same as in an environment with constant temperature and so in an environment with variable temperature. Application of the mathematical model provides the possibility to save significantly power resources expended for drying process.The paper gives description of methodology for calculation of technologically important optimum parameters for sintering processes of agglomeration while using milled peat.

  6. 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.

  7. 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

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

    International Nuclear Information System (INIS)

    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)

  9. Activity measurement and effective dose modelling of natural radionuclides in building material

    International Nuclear Information System (INIS)

    In this paper the assessment of natural radionuclides' activity concentration in building materials, calibration requirements and related indoor exposure dose models is presented. Particular attention is turned to specific improvements in low-level gamma-ray spectrometry to determine the activity concentration of necessary natural radionuclides in building materials with adequate measurement uncertainties. Different approaches for the modelling of the effective dose indoor due to external radiation resulted from natural radionuclides in building material and results of actual building material assessments are shown. - Highlights: • Dose models for indoor radiation exposure due to natural radionuclides in building materials. • Strategies and methods in radionuclide metrology, activity measurement and dose modelling. • Selection of appropriate parameters in radiation protection standards for building materials. • Scientific-based limitations of indoor exposure due to natural radionuclides in building materials

  10. Correlation of electrical reactor cable failure with materials degradation

    International Nuclear Information System (INIS)

    Complete circuit failure (shortout) of electrical cables typically used in nuclear power plant containments is investigated. Failure modes are correlated with the mechanical deterioration of the elastomeric cable materials. It is found that for normal reactor operation, electrical cables are reliable and safe over very long periods. During high temperature excursions, however, cables pulled across corners under high stress may short out due to conductor creep. Severe cracking will occur in short times during high temperatures (>1500C) and in times of the order of years at elevated temperatures (1000C to 1400C). A theoretical treatment of stress distribution responsible for creep and for cracking by J.E. Reaugh of Science Applications, Inc. is contained in the Appendix. 29 refs., 32 figs

  11. 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.

  12. Natural Radioactivity in Clay and Building Materials Used in Latvia

    Directory of Open Access Journals (Sweden)

    Riekstina D.

    2015-06-01

    Full Text Available This paper presents the results of natural radionuclide concentration and activity index study in materials used for construction in Latvia. Special attention is given to clay and clay ceramics. Concentrations of K-40 and Th- 232, U-238 radioactivity were determined using gamma-spectrometry method. In some building ware, maximal concentration of K-40 was 1440 Bq/kg, and of U-238 - 175 Bq/kg. In granite, the determined maximum concentration of Th-232 was 210 Bq/kg. It was found that radionuclide content in different period clay deposits can differ by more than two times, and up to five times in different clay ceramics. The results obtained are compared with analogous data from the other Baltic and North European countries.

  13. Determination of fungal spore release from wet building materials

    DEFF Research Database (Denmark)

    Kildesø, J.; Wurtz, H.; Nielsen, Kristian Fog; Kruse, P.; Wilkins, K.; Thrane, Ulf; Gravesen, S.; Nielsen, P.A.; Schneider, T.

    2003-01-01

    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...

  14. Determination of fungal spore release from wet building materials

    DEFF Research Database (Denmark)

    Kildesø, J.; Wurtz, H.; Nielsen, Kristian Fog;

    2003-01-01

    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......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...... 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...

  15. Determination of radioactivity levels from some Egyptian building materials

    International Nuclear Information System (INIS)

    Our world is radioactive and has been, since it was created. Over 60 radionuclides (radioactive elements) can be found in nature. Radon is naturally occurring radioactive gas, that is produced by the radioactive decay of radium. Breathing high concentration of radon can cause lung cancer. A set of experiments were carried out using Cr-39 as solid state nuclear track detectors with the optimum etching conditions, 6.25 N Na OH at 70oC for 8 hours. The radon-222 activity in this survey was found to be in the range of 0.303 kBq/m3 to 5.04 KBq/m3 for different building materials in Egypt

  16. Radon exhalation in building materials of Bangalore Metropolitan, India

    International Nuclear Information System (INIS)

    Radiations ply an important role in the environment, as the world is naturally radioactive and human beings are exposed to naturally occurring background radiation. It is a fact that, radioactivity can be in the air we breathe, the soil on which we walk, the dwellings which we live and even within our bodies. This paper discusses the results of radon exhalation in building materials of Bangalore Metropolitan, India. The area of present study is Bangalore Metropolis covering an area of about 220 km2, situated at a latitude 1258 N and longitude of 7736 E with an average altitude of about 910 m above mean sea level. Solid State Nuclear Track Based CAN technique method is adopted for radon exhalation studies. The results of radon exhalation rate had a large fluctuation depending on the measurement points, samples and the building materials and the range of radon surface exhalation rates in the sites were varied from 96.0 to 725.6 mBqm-3h-1 with the arithmetic mean (AM) and geometric mean (GM) as 603.3 ± 18.6 and 578.9 ± 18.6 mBqm-3h-1 respectively. The correlation between the surface exhalation rates, mass exhalation and radon concentration in dwellings were 0.96 and 0.91 respectively. The back ground gamma radiation levels ranged from 3.7 to 5.6 mSvy-1with AM and GM as 4.7 ± 0.6 mSvy-1 respectively. The measurements showed the concentration levels are at alarming levels and demands proper control measures. The details are discussed. (author)

  17. Numerical evaluation of material's degradation under various irradiation conditions

    International Nuclear Information System (INIS)

    Structural materials during a use in a fission reactor are subjected to irradiation by high energy neutrons, and therefore the properties, functions, and performances of materials become gradually degraded. Since keeping material's integrity is a key to success towards a stable operation of reactors, materials degradation due to irradiation should be taken into account when reactor design and maintenance are considered. One of the issues to be solved for realization of a long term operation is how the integrity of materials in use is ensured for a long time beyond an actually-experienced operation period. To do this, the future ageing behavior of materials should be understood in advance. Usually, an attempt is made to understand the behavior using the existing irradiation facilities with accelerated irradiation environments. In many cases, however, material's behavior depends much on acceleration coefficients and its dependency is not so simple. To overcome such a difficulty, a numerical simulation study is employed. In the present study, reaction rate analysis is performed to investigate material microstructure changes under various irradiation conditions. Our results have shown that volume swelling due to irradiation is very much different depending on irradiation conditions provided by such irradiation facilities as HFIR, JOYO, KUR, 14 MeV fusion neutrons. Based on the results, irradiation correlation methodology is discussed to predict material's degradation under arbitrary irradiation conditions using the actual existing data obtained with accelerated irradiation conditions. (author)

  18. 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.

    2016-06-01

    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.

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

    OpenAIRE

    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, resulting in early replacement and high cleaning costs, (2) Material damage, and (3) Health problems. However, current legislation forces manufacturers to reduce the biocide load, which requires manufa...

  20. Probabilistic material degradation model for aerospace materials subjected to high temperature, mechanical and thermal fatigue, and creep

    Science.gov (United States)

    Boyce, L.

    1992-01-01

    A probabilistic general material strength degradation model has been developed for structural components of aerospace propulsion systems subjected to diverse random effects. The model has been implemented in two FORTRAN programs, PROMISS (Probabilistic Material Strength Simulator) and PROMISC (Probabilistic Material Strength Calibrator). PROMISS calculates the random lifetime strength of an aerospace propulsion component due to as many as eighteen diverse random effects. Results are presented in the form of probability density functions and cumulative distribution functions of lifetime strength. PROMISC calibrates the model by calculating the values of empirical material constants.

  1. 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.

  2. Radiation interaction with composite materials: Building materials mixed with trommel sieve waste in different proportions

    International Nuclear Information System (INIS)

    Building materials (Portland cement, lime and pointing) mixed with different percentages (25, 50, 75%) of trommel sieve waste have been studied with respect to the photon interaction parameters. Measurements of the total mass attenuation coefficients of building materials mixed with trommel sieve waste (TSW) have been carried out using a high resolution Si(Li) detector. These coefficients were then used to calculate photon interaction cross sections, effective atomic numbers and effective electron densities. A narrow beam good geometry set-up was performed using a gamma radiation source (Cd109) of different energies. Photon interaction parameters were discussed on the basis of photon energy and chemical composition. The experimentally obtained values of photon interaction parameters have been compared with the ones calculated from theory.

  3. A novel method to control hydrolytic degradation of nanocomposite biocompatible materials via imparting superhydrophobicity

    Science.gov (United States)

    Khakbaz, Mobina; Hejazi, Iman; Seyfi, Javad; Jafari, Seyed-Hassan; Khonakdar, Hossein Ali; Davachi, Seyed Mohammad

    2015-12-01

    Acceleration of hydrolytic degradation of biomedical materials is not always desirable. For instance, terpolymers based on L-lactide, glycolide and trimethylene carbonate exhibit very fast hydrolytic degradation due to their amorphous structure, hydrophilicity, and high water absorption capability. Therefore, an attempt was made in the current study to impede the hydrolytic degradation for these materials through imparting superhydrophobicity to their surfaces. The used terpolymer has been shown to have promising potential applications as bio-absorbable surgical sutures and other biomedical materials, and thus, its applicability could be further extended upon impeding its hydrolytic degradation. Moreover, a novel method including combined use of non-solvent and nanoparticles was utilized to achieve superhydrophobicity. Very diverse wettability results were obtained which were attributed to the obtained various morphologies according to scanning electron microscopy results. More importantly, a unique hierarchical morphology was found to be responsible for the observed water repellent behavior. X-ray photoelectron spectroscopy results revealed co-existence of nanosilica particles and terpolymer chains on the surface's top layer. Finally, it was found that the superhydrophobic sample exhibited a significantly impeded hydrolytic degradation as compared with the hydrophilic pure terpolymer which was attributed to the formation of air pockets on the surface's top layer.

  4. Utilizing Repurposed Materials to Construct Utility Buildings and Small Animal Shelters

    OpenAIRE

    Chapman, C. Kim

    2014-01-01

    This fact sheet describes how to use repurposed materials such as shipping pallets, scraps from construction sites or other building projects, to construct utility buildings and small animal shelters.

  5. Materials and degradation modes in an alternative LLW [low-level waste] disposal facility

    International Nuclear Information System (INIS)

    The materials used in the construction of alternative low-level waste disposal facilities will be subject to interaction with both the internal and the external environments associated with the facilities and unless precautions are taken, may degrade, leading to structural failure. This paper reviews the characteristics of both environments with respect to three alternative disposal concepts, then assesses how reaction with them might affect the properties of the materials, which include concrete, steel-reinforced concrete, structural steel, and various protective coatings and membranes. It identifies and evaluates the probability of reactions occurring which might lead to degradation of the materials and so compromise the structure. The probability of failure (interpreted relative to the ability of the structure to restrict ingress and egress of water) is assessed for each material and precautionary measures, intended to maximize the durability of the facility, are reviewed. 19 refs., 2 tabs

  6. Lifetime analysis of WWER Reactor Pressure Vessel Internals concerning material degradation

    International Nuclear Information System (INIS)

    Present study aims at extending the operational lifetime of its WWER 440 type Units. Namely, the purpose of this task is to perform evaluative analysis of presumable changes in material properties of WWER 440 RVI. In line with this objective, making use of this analysis, this study shall determine that are there degradation mechanism, which limits the lifetime of the structural elements

  7. 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.

  8. A Review of Material Degradation Modelling for the Analysis and Design of Bioabsorbable Stents.

    Science.gov (United States)

    Boland, Enda L; Shine, Rosa; Kelly, Nicola; Sweeney, Caoimhe A; McHugh, Peter E

    2016-02-01

    The field of percutaneous coronary intervention has witnessed many progressions over the last few decades, more recently with the advancement of fully degradable bioabsorbable stents. Bioabsorbable materials, such as metallic alloys and aliphatic polyesters, have the potential to yield stents which provide temporary support to the blood vessel and allow native healing of the tissue to occur. Many chemical and physical reactions are reported to play a part in the degradation of such bioabsorbable materials, including, but not limited to, corrosion mechanisms for metals and the hydrolysis and crystallization of the backbone chains in polymers. In the design and analysis of bioabsorbable stents it is important to consider the effect of each aspect of the degradation on the material's in vivo performance. The development of robust computational modelling techniques which fully capture the degradation behaviour of these bioabsorbable materials is a key factor in the design of bioabsorable stents. A critical review of the current computational modelling techniques used in the design and analysis of these next generation devices is presented here, with the main accomplishments and limitations of each technique highlighted. PMID:26271520

  9. Complex degradation and ageing phenomena of research reactor core structural materials - experience at 14 MW TRIGA reactor from INR Pitesti

    International Nuclear Information System (INIS)

    The 14 MW TRIGA Research Reactor designed in the early '70s is a relative new research reactor with an operational experience of 30 years. The specific design of reactor core objectives, were to manufacture, build and operate a flexible structure which incorporate previous experience of pool type research reactors. Aluminum alloy 6061 and stainless steel are only materials used for core structural components, which are all easily remotely removable and replaceable by simple hand tools. Properties of those categories of materials were well characterized / known for many other reactors predecessors, and no special criteria or preliminary tests were performed. The mechanical core structure is presented in the paper and designed procedure for periodic testing and inspection is also described. In spite of well known materials properties, the behavior uncertainties of those materials in each reactor case may have special aspects related to design of components, manufacturing technologies, surface finishing and processing, quality control methods, price of specific components, complex conditions in core and vicinity, history of operation, inspection and verification of components, radioactive waste characterization at the end of life of components. Limited assessment of materials properties and suitability for certain application without considering the each individual component load, exposure and life time, may produce limited information on material itself, in fact the issue is the selection criteria for a standard material suitable for a certain application and consequent failure of components. The degradation and ageing are specific to components starting from design, manufacturing technology and expected life when the component should be replaced. The paper presents the practical experience on maintenance requirements specific to TRIGA core components and some techniques of material investigations available at Institute for Nuclear Research Pitesti Post Irradiation

  10. Thermal degradation and fire behaviour of thermal insulation materials based on food crop by-products

    OpenAIRE

    Lacasta Palacio, Ana María; Palumbo Fernández, Mariana; Formosa Mitjans, Joan

    2015-01-01

    Natural thermal insulation materials developed from renewable crop by-products and natural binders are analysed in terms of their thermal degradation and fire behaviour. A Pyrolysis Combustion Flow Calorimetre (PCFC) is used to characterise some kinds of crop by-products, including rice husk, corn pith and barley straw. This technique is complemented with a TG analysis. Six thermal insulation materials, formulated with such crop by-products and two kind of natural binders, corn st...

  11. 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.

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

    International Nuclear Information System (INIS)

    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

  13. NATURAL RADIOACTIVITY IN SOME BUILDING MATERIALS USING A GAMMA-RAY SPECTROMETER

    OpenAIRE

    AKKURT, Iskender; Betül MAVİ

    2011-01-01

    The main reason for the natural radioactivity in the earth is decay series of 40K, 238U and 232Th radionuclides. Because all building materials are soil product, they contain these radionuclides as natural so that building materials have different amounts of radioactivity. In this study the concentrations of natural radioactivity levels of the commonly used natural building materials in Isparta region have been determined. The samples have been analysed using a NaI(Tl) ƒ×-ray spectrometer sy...

  14. 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)

  15. Characterization of gas concrete materials used in buildings of Turkey

    International Nuclear Information System (INIS)

    The activity concentration of 226Ra, 232Th and 40K in gas concrete samples collected from different suppliers and some provinces in Turkey were measured using gamma-ray spectrometry. Knowledge of radioactivity in gas concrete used in building materials enables one to assess any possible radiological risks to human health. The mean activity concentrations observed in the gas concrete samples were 82.0, 28.2 and 383.9 Bq kg-1 for 226Ra, 232Th and 40K, respectively. The radium equivalent activity, external and internal hazard indices as well as terrestrial absorbed dose and annual effective dose rate was calculated. The results indicate that the radium equivalent activity values of gas concrete samples are lower than the limit of 370 Bq kg-1, equivalent to a gamma-dose of 1.5 mSv y-1. Moreover, mass attenuation coefficients were measured in some gas concrete samples. It was found that the mass attenuation coefficients decreased with increasing photon energies. Also, chemical compositions and structural analysis (XRD and SEM) of the gas concrete samples were investigated.

  16. Characterization of gas concrete materials used in buildings of Turkey.

    Science.gov (United States)

    Damla, N; Cevik, U; Kobya, A I; Celik, A; Van Grieken, R; Kobya, Y

    2009-09-15

    The activity concentration of (226)Ra, (232)Th and (40)K in gas concrete samples collected from different suppliers and some provinces in Turkey were measured using gamma-ray spectrometry. Knowledge of radioactivity in gas concrete used in building materials enables one to assess any possible radiological risks to human health. The mean activity concentrations observed in the gas concrete samples were 82.0, 28.2 and 383.9 Bq kg(-1) for (226)Ra, (232)Th and (40)K, respectively. The radium equivalent activity, external and internal hazard indices as well as terrestrial absorbed dose and annual effective dose rate was calculated. The results indicate that the radium equivalent activity values of gas concrete samples are lower than the limit of 370 Bq kg(-1), equivalent to a gamma-dose of 1.5 mSv y(-1). Moreover, mass attenuation coefficients were measured in some gas concrete samples. It was found that the mass attenuation coefficients decreased with increasing photon energies. Also, chemical compositions and structural analysis (XRD and SEM) of the gas concrete samples were investigated. PMID:19297097

  17. Antique and modern building materials in Germany; Doitsu no jutakuyo kenzai

    Energy Technology Data Exchange (ETDEWEB)

    Urabe, K. [Ryukoku University, Kyoto (Japan). Faculty of Science and Engineering

    1996-11-20

    This article introduces antique and modern building materials through a lot of photographs taken during a stay for one year in Germany from the viewpoint of researcher of building materials. For the antique buildings, rock materials peculiar to local districts are used. In the northern part of Germany, bricks made of clay from Pliocene strata are used due to lack of rock materials. For the modern buildings, only a few kinds of building materials are used, such as clay bricks and concrete. In European countries, it is strongly considered that even private dwelling houses compose a part of aspect of city and town, which results in the strict construction conditions. In Japan, recently, construction of dwelling houses has been also regulated depending on regions, which will be enriched with the maturity of society. Under such a situation, materials with low price including construction price and high durability are to be required. Ceramic panel materials are prospective. 1 ref., 8 figs.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. VOC sink behaviour on building materials--model evaluation

    Science.gov (United States)

    The event of 11 September 2001 underscored the need to study the vulnerability of buildings to weapons of mass destruction (WMD), including chemical, biological, physical, and radiological agents. Should these agents be released inside a building, they would interact with interio...

  3. Selected Issues Concerning Degradation of Material in the Production of Injection Molded Plastic Components

    Directory of Open Access Journals (Sweden)

    Jałbrzykowski Marek

    2016-09-01

    Full Text Available This paper presents the problem of thermal degradation of thermoplastic materials processed using the injection method. Attention was paid to the issue of the optimal selection of a dye for modifying the base materials. For the selected materials and dyes, derivatograph tests were performed in order to assess their thermal characteristics and breakdown kinetics. Additionally, tribological tests and microscope observations of selected samples were performed. The obtained test results suggest a diverse level of thermal processes in the analyzed materials. This is crucial for the appropriate selection of dyes for plastic materials. As it turned out, the tribological properties of materials can also influence the technological quality of the injected alloy.

  4. Thermal conductivity degradation analyses of LWR MOX fuel by the quasi-two phase material model

    International Nuclear Information System (INIS)

    The temperature measurements of mixed oxide (MOX) and UO2 fuels during irradiation suggested that the thermal conductivity degradation rate of the MOX fuel with burnup should be slower than that of the UO2 fuel. In order to explain the difference of the degradation rates, the quasi-two phase material model is proposed to assess the thermal conductivity degradation of the MIMAS MOX fuel, which takes into account the Pu agglomerate distributions in the MOX fuel matrix as fabricated. As a result, the quasi-two phase model calculation shows the gradual increase of the difference with burnup and may expect more than 10% higher thermal conductivity values around 75 GWd/t. While these results are not fully suitable for thermal conductivity degradation models implemented by some industrial fuel manufacturers, they are consistent with the results from the irradiation tests and indicate that the inhomogeneity of Pu content in the MOX fuel can be one of the major reasons for the moderation of the thermal conductivity degradation of the MOX fuel. (author)

  5. Limitations on the Activity Concentration of Mineral Processing Residues Used as Building Material

    International Nuclear Information System (INIS)

    The use of mineral processing residue as a building material accounts for a significant proportion of the various uses of such material. The activity concentrations of radionuclides of natural origin in the material can be significantly elevated, resulting in enhanced exposure of occupants of the buildings concerned unless some restriction is placed on the radioactivity content. Accordingly, in order to comply with the dose limitation requirements of the relevant laws and standards, the activity concentration in the material has to be restricted. The use of mineral processing residues in building material is controlled in three categories according to a parameter known as the equivalent concentration, which can guide the product specification of the building material and control the dose received by a building occupant. (author)

  6. 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.

  7. 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.

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

    International Nuclear Information System (INIS)

    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

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. Nest-building males trade-off material collection costs with territory value

    OpenAIRE

    Bailey, Ida; Morgan, Kate; Oschadleus, D; DeRuiter , SL; Meddle, Simone; Healy, Susan D.

    2016-01-01

    Building a structurally robust nest is crucial for reproductive success in manybirds. However, we know little about the criteria birds use to select material or where they go to collect it. Here we observed the material collection of male cape weaverbirds (Ploceus capensis). Males typically selected long, strong material to build their nests and each male collected material from different locations. Males that built more nests nested in a different area of the colony and flew further to colle...

  14. 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

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

    International Nuclear Information System (INIS)

    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

  16. 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

  17. Building materials. VOC emissions, diffusion behaviour and implications from their use

    International Nuclear Information System (INIS)

    Five cement- and five lime-based building materials were examined in an environmental chamber for their emissions of Volatile Organic Compounds (VOCs). Typical VOCs were below detection limits, whereas not routinely analysed VOCs, like neopentyl glycol (NPG), dominated the cement-based products emissions, where, after 72 h, it was found to occur, in levels as high as 1400 μg m−3, accounting for up to 93% of total VOCs. The concentrations of NPG were not considerably changed between the 24 and 72 h of sampling. The permeability of building materials was assessed through experiments with a dual environmental chamber; it was shown that building materials facilitate the diffusion of chemicals through their pores, reaching equilibrium relatively fast (6 h). - Highlights: ► Neopentyl glycol is reported in emissions from building materials for the first time. ► Neopentyl glycol dominates the VOC emissions from cement-based building materials. ► A dual chamber was developed to control diffusion through building materials. ► Building materials facilitate diffusion of indoor air pollutants through their pores. - Neopentyl glycol was detected in high concentrations in emissions from building materials.

  18. Calculation of radiation dose rate arisen from radionuclide contained in building materials

    International Nuclear Information System (INIS)

    This paper presents some results that we used MCNP5 program to calculate radiation dose rate arisen from radionuclide in building materials. Since then, the limits of radionuclide content in building materials are discussed. The calculation results by MCNP are compared with those calculated by analytical method. (author)

  19. Degradation of material properties significant for lifetime extension of nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Erhard, Anton [Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin (Germany). Dept. III ' Containment Systems for Dangerous Goods' ; Otremba, Frank [Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin (Germany). Div. III.1 ' Dangerous Good Packaging'

    2010-07-01

    The discussion about the right energy sources or alternative energy generation goes around the world, mostly in connection with greenhouse gas reduction. Therefore, some countries have started to consider extending operation of nuclear power plants. This demands an extensive plant life management as well as the knowledge of the degradation in material properties. The Basis Safety Concept (BSC) in Germany observed this circumstance. Still, lifetime extension is not an issue in Germany due to phase out of nuclear energy. Part of the BSC is the application of non-destructive examination (NDE) methods from the beginning, i.e. from component manufacture, to the end of life. The application of a NDE method to detect and size defects in components in nuclear power plants is presented. Some material properties and their degradation during increase of operation time are also in the focus of this paper. (orig.)

  20. Study of radiation dose reduction of buildings of different sizes and materials

    International Nuclear Information System (INIS)

    The dependence of radiation dose reduction on the sizes and materials of buildings was studied by numerical analyses using the Monte Carlo simulation code, PHITS. The dose rates inside the buildings were calculated by simulating gamma-ray transport from radioactive cesium deposited at the ground surface. Three building models were developed: the wooden house, the open-space concrete building, and the thin-wall building, to study the effect of building size and construction material on dose reduction inside these structures. Here the floor-area sizes of the building models were varied to clarify the influence of building configuration on dose reduction. The results demonstrated that the dose rates inside the buildings linearly decreased with increasing floor area on a logarithmic scale for all types of buildings considered. The calculated dose distribution inside a building indicated that the distance from the outer walls was a determining factor for the dose rate at each position in the building. The obtained tendency was verified by comparison with data reflecting the dose reduction of typical buildings in Japan. (author)

  1. 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.

  2. Strength degradation and failure limits of dense and porous ceramic membrane materials

    DEFF Research Database (Denmark)

    Pećanac, G.; Foghmoes, Søren Preben Vagn; Lipińska-Chwałek, M.;

    2013-01-01

    failure potential of these membrane parts, where in a complex device also the highest residual stresses should arise due to differences in thermal expansion. In particular, sensitivity of the materials to subcritical crack growth was assessed since the long-term reliability of the component does not only...... depend on its initial strength, but also on strength degradation effects. The results were subsequently used as a basis for a strength–probability–time lifetime prediction....

  3. 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.

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

    OpenAIRE

    Spišáková Marcela; Mačková Daniela

    2015-01-01

    The sustainable building has taken off in recent years with many investors looking for new and different methods of construction. The traditional building materials can be made out of natural materials, while others can help to lower energy costs of the occupant once built. Regardless of what the goal of the investor is, traditional building materials and their use is on the rise. The submitted paper provides an overview of natural building materials and possible modern building systems using...

  5. LWR aging management using a proactive approach to control materials degradation

    International Nuclear Information System (INIS)

    Material issues can be the limiting factor for the operation of nuclear power plants. There is growing interest in new and improved philosophies and methodologies for plant life management (PLiM), which include the migration from reliance on periodic inservice inspection to include condition-based maintenance. A further step in the development of plant management is the move from proactive responses based on ISI to become proactive, through the investigation of the potential for implementation of a proactive management of materials degradation (PMMD) program and its potential impact on the management of LWRs. (author)

  6. 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) =Health Physics, 48, 87-95. 6. Uosif M.A.M. (2014). Estimation of Radiological Hazards of Some Egyptian Building Materials Due to Natural Radioactivity. International Journal of u- and e- Service, Science and Technology. Vol.7, No.2 (2014), pp.63-76

  7. Degradation of wide band-gap electrolumienscent materials by exciton-polaron interactions (Presentation Recording)

    Science.gov (United States)

    Aziz, Hany; Wang, Qi

    2015-10-01

    The limited performance stability and gradual loss in the electroluminescence efficiency of OLEDs utilizing wide band-gap materials, such as blue-emitting phosphorescent and fluorescent devices, continues to be a challenge for wider technology adoption. We recently found that interactions between excitons and polarons play an important role in the aging behavior of electroluminescent materials, and that a correlation exists between the susceptibility of these materials to this aging mode and their band-gap. This degradation mode is also found to be often associated with the emergence of new bands - at longer wavelength - in the electroluminescence spectra of the materials, that can often be detected after prolonged electrical driving. Such bands contribute to the increased spectral broadening and color purity loss often observed in these devices over time. Exciton-polaron interactions, and the associated degradation, are also found to occur most significantly in the vicinity of device inter-layer interfaces such as at the interface between the emitter layer and the electron or hole transport layers. New results obtained from investigations of these phenomena in a wide range of commonly used host and guest OLED materials will be presented.

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

    International Nuclear Information System (INIS)

    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 oC 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.

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

    Directory of Open Access Journals (Sweden)

    H. L. Throop

    2012-11-01

    Full Text Available 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.

  10. Natural radioactivity and associated radiation hazardous of main building materials in Yan'an, China

    International Nuclear Information System (INIS)

    Background: With the rapidly economic development and urbanization in Yan'an city, more building materials were consumed in building construction. While the natural radioactivity level of building materials from Yan'an is limited in the literatures. Purpose: The main objective of this study is to determine the natural radioactivity level and to analyze the associated radiation hazards of building materials in Yan'an. Methods: The specific activities of natural radionuclides 226Ra, 232Th and 40K in various building materials from Yan'an city were determined using low-background gamma-ray spectrometry, and their radiation hazards were evaluated according to the standard methods. Results: The results show that the specific activities of 226Ra, 232Th and 40K in the building materials are 9.4-73.1, 11.5-86.9 and 258.9-1055.1 Bq/kg, respectively. The activities of 226Ra and 232Th, except for sand and gravel aggregate, in all other building materials are higher than the corresponding means of local soil, and the activities of 40K in hollow brick, red-clay brick, sand and gravel aggregate exceed the means of 40K in soil. However, the values of internal exposure index, external exposure index and gamma radiation index in all investigated building materials are less than 1. Conclusions: The radiation levels of all analyzed building materials are within the national safety standard, which indicates that all analyzed building materials can be used anywhere and they can't cause radiation hazard to the local residents. (authors)

  11. Naturally radioactivity in common building materials used in Thiruvannamalai city, Tamilnadu, India

    International Nuclear Information System (INIS)

    The radioactivity of some building materials used in Thiruvannamalai city has been measured using a NaI(Tl) detector based gamma ray spectrometer. The distribution of natural occurring radionuclides (226Ra, 232Th and 40K) in the building materials was studied. The radium equivalent activity (Raeq), external hazard index (Hex) internal radiation hazard index (Hin) and the activity utilization index (I) associated with the natural radionuclide are calculated to assess the radiation hazard of the natural radioactivity in the building materials. The present work shows that the natural radioactivity levels in the building construction materials used in Thiruvannamalai city is well below the acceptable limits. From the analysis, it was found that these materials may be safely used as construction materials and do not pose significant radiation hazards. (author)

  12. Measurement of natural radioactivity in common building materials used in Tiruvannamalai, Tamilnadu, India

    International Nuclear Information System (INIS)

    The radioactivity of some building materials used in Tiruvannamalai city has been measured using a NaI (Tl) detector based gamma ray spectrometer. The distribution of natural occurring radionuclides (226Ra, 232Th and 40K) in the building materials was studied. The radium equivalent activity (Raeq), the activity utilization index (I), external hazard index (Hex) and internal radiation hazard index (Hin) associated with the natural radionuclide are calculated to assess the radiation hazard of the natural radioactivity in the building materials. The present work shows that the natural radioactivity levels in the building construction materials used in Tiruvannamalai city is well below the acceptable limits. From the analysis, it was found that these materials may be safely used as construction materials and do not pose significant radiation hazards. (author)

  13. The natural radioactivity in common building materials around Tiruvannamalai city, Tamilnadu, India

    International Nuclear Information System (INIS)

    Most building materials contain naturally occurring radioactive elements. By the determination of the radioactivity level in building materials, the indoor radiological hazard to human health can be assessed. This helps in taking important precautionary measures whenever the dose rate is found to be above the recommended limits. In this paper, the samples of commonly used raw materials and building products have been collected around the Tiruvannamalai city, Tamilnadu to determine the activity concentration of natural radionuclides were determined by gamma ray spectrometer. The radiological hazards in the building materials due to the natural radioactivity were inferred from the calculations of radium equivalent activity (Raeq) and the criteria formula. These radiological parameters were evaluated and compared with the internationally recommended values. From the analysis, it was found that these materials may be safely used as construction materials and do not pose significant radiation hazards. (author)

  14. 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. PMID:26761603

  15. 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

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

    International Nuclear Information System (INIS)

    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 δ34S and δ18O 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 34S, 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: → Insight in stone weathering mechanisms by multi-isotope fingerprinting (B, S, O). → Intrinsic sulphate sources (gypsum plaster, mortar) contribute to stone degradation. → Origin of building materials determined by

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

    OpenAIRE

    Cviklovič Vladimír; Paulovič Stanislav

    2014-01-01

    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 stabili...

  18. Evaluation of activity concentration limits for building materials using voxel phantom

    International Nuclear Information System (INIS)

    To protect the public from natural radioactive materials, it is necessary to consider the building materials because of natural radioactivity and quantity. There is an annual effective dose limit of 1mSv for products, but an activity concentration limit is necessary for the product screening. We derived the specific effective dose rates by building materials with the MCNPX code and evaluated the activity concentration limits. Using these values, we can suggest the activity concentration index as the following formula

  19. Clearance of materials, buildings and land with low content of radioactive materials. Methodology and documentation

    International Nuclear Information System (INIS)

    The concepts and methods of clearance of materials originating from the decommissioning af the nuclear facilities at Risoe National Laboratory are described as well as procedures for clearance of buildings and land. The recommendations from international organisations as well as national regulation on clearance are presented. Methods for characterisation and separation of waste being candidate for clearance are presented.Di .erent methodologies for determining the content of radionuclides in candidate waste for clearance are discussed,and the need for and construction of a low-level laboratory for activity analyses in both bulky and less bulky subjects is described. Laboratory analyses, documentation of results and education of health physics personnel is presented. (au)

  20. INR experience concerning the assessment of the CANDU steam generator tubing material degradation

    International Nuclear Information System (INIS)

    Steam generator degradation has caused substantial losses of power generation, resulted in large repair and maintenance costs. Institute for Nuclear Research has carried out an extensive R and D program focused on the understanding of the degradation processes especially for the tubing material and on developing remedial actions in the purpose to prevent and diminish the ageing process of which evolution supposes some considerable economic costs. Because of the huge impact of corrosion, it is imperative to have a systematic approach to recognizing and mitigating corrosion problems as soon as possible after they become apparent. A proper failure analysis includes collection of pertinent background data and service history, followed by visual inspection, photographic documentation, material evaluation, data review and conclusion procurement. In analyzing corrosion failures, one must recognize the wide range of common corrosion mechanisms. The features of any corrosion failure give strong clues as to the most likely cause of the corrosion. The principal steps of analysis and diagnosis of the steam generator tubes degradations consist in: visual inspection, chemical analysis, cross section examination by optical and scanning electron microscopy and RDX, data review, conclusions and recommendations. This paper details a proven approach to properly determining the root cause of a failure, and includes metallographic illustrations of the most common corrosion mechanisms, including general corrosion, pitting, crevice corrosion, corrosion fatigue and intergranular corrosion. (author)

  1. Material degradation management of the reactor coolant system at the Point Lepreau Generating Station

    International Nuclear Information System (INIS)

    In the past decade, the Point Lepreau Generating Station (PLGS) has experienced some serious degradation in the major components of the primary heat transport system (HTS). Environmental cracking of PLGS carbon steel feeder piping, previously unknown in the industry, presented unique challenges and drove New Brunswick Power Nuclear (NBPN) to implement an aggressive and proactive life management program. The successful implementation of the feeder piping management plan has led to a similar approach for other components and for the HTS itself as a system. Numerous documents have been published by organizations such as the International Atomic Energy Agency, Electric Power Research Institute, Nuclear Energy Institute, and the Institute of Nuclear Power Operations that provide generic and specific guidance for developing and maintaining processes for component life management. To ensure the anticipated benefits of the guidelines documents are realized, a significant number of operations and maintenance (O and M) activities must be identified and effectively implemented. Utilities and industry working groups strive to do this most effectively for their own needs, often working together to make best use of others' experience. The continued development of the PLGS HTS materials degradation management program is based on industry guideline document principles. However, it has been the experience and best practices learned from other utilities, service providers, and within NBPN that has been key to the successful implementation of plans. This paper shares some of the most effective and practical features of the PLGS HTS materials degradation management program. (author)

  2. The relation of microdamage to fracture and material property degradation in human cortical bone tissue

    Science.gov (United States)

    Akkus, Ozan

    This dissertation investigates the relation of microdamage to fracture and material property degradation of human cortical bone tissue. Fracture resistance and fatigue crack growth of microcracks were examined experimentally and material property degradation was examined through theoretical modeling. To investigate the contribution of microdamage to static fracture resistance, fracture toughness tests were conducted in the transverse and longitudinal directions to the osteonal orientation of normal bone tissue. Damage accumulation was monitored by acoustic emission during testing and was spatially observed by histological observation following testing. The results suggested that the propagation of the main crack involved weakening of the tissue by diffuse damage at the fracture plane and by formation of linear microcracks away from the fracture plane for the transverse specimens. For the longitudinal specimens, growth of the main crack occurred in the form of separations at lamellar interfaces. Acoustic emission results supported the histological observations. To investigate the contribution of ultrastructure to static fracture resistance, fracture toughness tests were conducted after altering the collagen phase of the bone tissue by gamma radiation. A significant decrease in the fracture toughness, Work-to-Fracture and the amount damage was observed due to irradiation in both crack growth directions. For cortical bone irradiated at 27.5kGy, fracture toughness is reduced due to the inhibition of damage formation at and near the crack tip. Microcrack fatigue crack growth and arrest were investigated through observations of surface cracks during cyclic loading. At the applied cyclic stresses, the microcracks propagated and arrested in less than 10,000 cycles. In addition, the microcracks were observed not to grow beyond a length of 150mum and a DeltaK of 0.5MNm-3/2, supporting a microstructural barrier concept. Finally, the contribution of linear microcracks to

  3. Environmental degradation of composites for marine structures: new materials and new applications.

    Science.gov (United States)

    Davies, Peter

    2016-07-13

    This paper describes the influence of seawater ageing on composites used in a range of marine structures, from boats to tidal turbines. Accounting for environmental degradation is an essential element in the multi-scale modelling of composite materials but it requires reliable test data input. The traditional approach to account for ageing effects, based on testing samples after immersion for different periods, is evolving towards coupled studies involving strong interactions between water diffusion and mechanical loading. These can provide a more realistic estimation of long-term behaviour but still require some form of acceleration if useful data, for 20 year lifetimes or more, are to be obtained in a reasonable time. In order to validate extrapolations from short to long times, it is essential to understand the degradation mechanisms, so both physico-chemical and mechanical test data are required. Examples of results from some current studies on more environmentally friendly materials including bio-sourced composites will be described first. Then a case study for renewable marine energy applications will be discussed. In both cases, studies were performed first on coupons at the material level, then during structural testing and analysis of large components, in order to evaluate their long-term behaviour.This article is part of the themed issue 'Multiscale modelling of the structural integrity of composite materials'. PMID:27242304

  4. Survey of degradation modes of candidate materials for high-level radioactive-waste disposal containers

    International Nuclear Information System (INIS)

    Three iron- to nickel-based austenitic alloys and three copper-based alloys are being considered as candidate materials for the fabrication of high-level radioactive-waste disposal containers. The austenitic alloys are Types 304L and 316L stainless steels and the high-nickel material Alloy 825. The copper-based alloys are CDA 102 (oxygen-free copper), CDA 613 (Cu-7Al), and CDA 715 (Cu-30Ni). Waste in the forms of both spent fuel assemblies from reactors and borosilicate glass will be sent to the prospective repository at Yucca Mountain, Nevada. The decay of radionuclides will result in the generation of substantial heat and gamma radiation. Container materials may undergo any of several modes of degradation in this environment, including undesirable phase transformations due to a lack of phase stability; atmospheric oxidation; general aqueous corrosion; pitting; crevice corrosion; intergranular stress corrosion cracking; and transgranular stress corrosion cracking. Problems specific to welds, such as hot cracking, may also occur. A survey of the literature has been prepared as part of the process of selecting, from among the candidates, a material that is adequate for repository conditions. The modes of degradation are discussed in detail in the survey to determine which apply to the candidate alloys and the extent to which they may actually occur. The eight volumes of the survey are summarized in Sections 1 through 8 of this overview. The conclusions drawn from the survey are also given in this overview

  5. Proceedings of the sixth international symposium on environmental degradation of materials in nuclear power systems - water reactors

    International Nuclear Information System (INIS)

    The operation of water reactor nuclear power plants provides a significant fraction of the world's electric power generation. At the end of 1992, approximately 360 such plants were in operation, representing a total generating capacity of 320 GWe. As these plants age, and as new designs evolve, the impact of environmental degradation of reactor materials on reliability and power plants economics is receiving increasing recognition. The Sixth International Symposium on Environmental Degradation of Materials in Nuclear Power Systems-Water Reactors was organized to provide a forum for exchange of the results of research and plant operating experience associated with material degradation

  6. Micro- and nano-scale characterization to study the thermal degradation of cement-based materials

    International Nuclear Information System (INIS)

    The degradation of hydration products of cement is known to cause changes in the micro- and nano-structure, which ultimately drive thermo-mechanical degradation of cement-based composite materials at elevated temperatures. However, a detailed characterization of these changes is still incomplete. This paper presents results of an extensive experimental study carried out to investigate micro- and nano-structural changes that occur due to exposure of cement paste to high temperatures. Following heat treatment of cement paste up to 1000 °C, damage states were studied by compressive strength test, thermogravimetric analysis (TGA), scanning electron microscopy (SEM) atomic force microscopy (AFM) and AFM image analysis. Using experimental results and research from existing literature, new degradation processes that drive the loss of mechanical properties of cement paste are proposed. The development of micro-cracks at the interface between unhydrated cement particles and paste matrix, a change in C–S–H nano-structure and shrinkage of C–S–H, are considered as important factors that cause the thermal degradation of cement paste. - Highlights: • The thermal degradation of hydration products of cement is characterized at micro- and nano-scale using scanning electron microscopy (SEM) and atomic force microscopy (AFM). • The interface between unhydrated cement particles and the paste matrix is considered the origin of micro-cracks. • When cement paste is exposed to temperatures above 300 ºC, the nano-structure of C-S-H becomes a more loosely packed globular structure, which could be indicative of C-S-H shrinkage

  7. Survey of degradation modes of candidate materials for high-level radioactive-waste disposal containers

    Energy Technology Data Exchange (ETDEWEB)

    Strum, M.J.; Weiss, H.; Farmer, J.C. (Lawrence Livermore National Lab., CA (USA)); Bullen, D.B. (Science and Engineering Associates, Inc., Pleasanton, CA (USA))

    1988-06-01

    This volume surveys the effects of welding on the degradation modes of three austenitic alloys: Types 304L and 316L stainless steels and Alloy 825. These materials are candidates for the fabrication of containers for the long-term storage of high-level nuclear waste. The metallurgical characteristics of fusion welds are reviewed here and related to potential degradation modes of the containers. Three specific areas are discussed in depth: (1) decreased resistance to corrosion in the forms of preferential corrosion, sensitization, and susceptibility to stress corrosion cracking, (2) hot cracking in the heat-affected zone and the weld zone, and (3) formation of intermetallic phases. The austenitic alloys are ranked as follows in terms of overall weldability: Alloy 825 (best) > Type 316L stainless steel > Type 304L stainless steel (worst). 108 refs., 31 figs., 7 tabs.

  8. Survey of degradation modes of candidate materials for high-level radioactive-waste disposal containers

    International Nuclear Information System (INIS)

    This volume surveys the effects of welding on the degradation modes of three austenitic alloys: Types 304L and 316L stainless steels and Alloy 825. These materials are candidates for the fabrication of containers for the long-term storage of high-level nuclear waste. The metallurgical characteristics of fusion welds are reviewed here and related to potential degradation modes of the containers. Three specific areas are discussed in depth: (1) decreased resistance to corrosion in the forms of preferential corrosion, sensitization, and susceptibility to stress corrosion cracking, (2) hot cracking in the heat-affected zone and the weld zone, and (3) formation of intermetallic phases. The austenitic alloys are ranked as follows in terms of overall weldability: Alloy 825 (best) > Type 316L stainless steel > Type 304L stainless steel (worst). 108 refs., 31 figs., 7 tabs

  9. Natural radioactivity and radiological hazards of building materials in Xianyang, China

    International Nuclear Information System (INIS)

    Common building materials collected from Xianyang, China were analyzed for the natural radioactivity of 226Ra, 232Th and 40K using γ-ray spectroscopy. The average activity concentration of 226Ra, 232Th and 40K in the studied building materials ranges from 13.4 to 69.9, 13.1–99.1 and 124.7–915.1 Bq kg−1, respectively. The measured activity concentrations for these radionuclides were compared with the reported data of other countries and with the worldwide average activity of soil. To assess the radiation hazard of the natural radioactivity in all samples to the people, the radium equivalent activity, external hazard index, internal hazard index, indoor absorbed dose rate and total annual effective dose were estimated. The radium equivalent activities of the studied samples are below the internationally accepted values. The external hazard index and internal hazard index of all analyzed building materials are less than unity. The mean values of indoor absorbed dose rate for all building materials except for lime are higher than the world population-weighted average of 84 nGy h−1 and the total annual effective dose values of building materials are lower than 1 mSv y−1 except for some cyan brick samples. The study shows the measured building materials do not pose significant source of radiation hazard and are safe for use in the construction of dwellings. - Highlights: ► Natural radioactivity in building materials was determined by gamma ray spectrometry. ► The radiological hazard of studied building materials is within the recommended safety limit. ► Most of the studied building materials do not pose significant radiation risk to residents.

  10. Environmental degradation of fiber reinforced plastic materials in neutral, acidic, and basic aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Barkatt, A.; Bank, L.C.; Gentry, T.R.; Prian, L.; Shan, R.; Sang, J.C.; Pollard, R. [Catholic Univ. of America, Washington, DC (United States)

    1995-10-01

    Kinetic measurements on the dissolution of oxide components of fiber-reinforced plastics show that the dissolution in aqueous media is a complex phenomenon and that changes in the nature of the controlling mechanism during the time of exposure can lead to an increase in rate. As a result, thorough understanding of the mechanisms is imperative in developing models for prediction of the long-term degradation of these composites. Thermogravimetric analysis has been found to be a promising indicator of the structural changes associated with the degradation process. Results obtained on specimens of concrete reinforcement rods made out of a E-glass/vinylester FRP material show that weight loss between 150 and 300 C is sensitively dependent on the nature of the corroding medium, the duration of exposure, and, in particular, the temperature at which the material was previously exposed. This weight loss correlates with the extent of moisture absorption. The enhanced weight loss between 150 and 300 C observed in the cases of samples previously exposed to attack by an aqueous media apparently reflects the increase in number of monomeric species as a result of the exposure. Increase in the effective area out of which monomers may volatilize as a result of the formation or propagation of microcracks, pores, or fiber-matrix interfacial gaps in the course of exposure may also contribute to enhanced weight loss. The conclusion that the extent of weight loss is indicative of the extent of degradation is supported by chemical, infrared and NMR analysis of the evolved vapors and by determination of their molecular weight. Both the weight loss at elevated temperatures and the tensile strength show a strong dependence on temperature and a parabolic time dependence. Raman spectroscopy is a highly sensitive and convenient technique of following structural changes. The techniques explored here can provide important data for modeling of the environmental degradation process.

  11. 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.

  12. 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.

  13. Gamma-ray attenuation coefficients of some building materials available in Egypt

    International Nuclear Information System (INIS)

    Mass attenuation coefficients of various types of building materials were measured using a high-resolution HPGe spectrometer detector. Samples were irradiated by gamma-rays emitted from point sources of 241Am, 133Ba, 60Co and 137Cs. The results are in good agreement with the theoretical calculations of XCOM code. The effectiveness of building materials in shielding were determined over the range 50-3000 keV. Finally, the protection efficiency of walls and roofs from radiation exposure were determined. The effectiveness of all tested building materials was better than the internationally accepted limit, and they are therefore acceptable for use.

  14. 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.

  15. 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.

  16. 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. 

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

    OpenAIRE

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

    1999-01-01

    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 mater...

  18. 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.

  19. Radioactivity of natural and artificial building materials – a comparative study

    International Nuclear Information System (INIS)

    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 226Ra, 232Th and 40K 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 226Ra content. Natural, i.e. adobe and also brick samples contain higher amount of 40K 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 to the

  20. Ozone reactions with indoor materials during building disinfection

    DEFF Research Database (Denmark)

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

    2007-01-01

    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...... constant, and typically low, value after approximately I I h. The four materials with the highest sustained deposition velocities were ceiling tile, office partition, medium density fiberboard and gypsum wallboard backing. Analysis of ozone reaction probabilities indicated that throughout each experiment...

  1. Materials ageing degradation programme in japan and proactive ageing management in NPP

    International Nuclear Information System (INIS)

    Predictive and preventive maintenance technologies are increasingly of importance for the long term operation (LTO) of Light Water Reactor (LWR) plants. In order for the realization LTO to be successful, it is essential that aging degradation phenomena should be properly managed by using adequate maintenance programs based on foreseeing the aging phenomena and evaluating their rates of development, where Nuclear Power Plants can be continued to operate beyond the original design life depending upon the regulatory authority rules. In combination with Periodic Safety Review (PSR) and adequate maintenance program, a plant life can be extended to 60 years or more. Plant Life Management (PLiM) is based upon various maintenance program as well as systematic safety review updated based upon the state of the art of science and technology. One of the potential life time limiting issue would be materials ageing degradation and therefore an extensive efforts have been paid world-widely. In 2007, NISA launched a national program on Enhanced Ageing Management Program and 4 nationwide clusters were formed to carry out the national program where materials ageing degradation was one of the major topics. In addition to these degradation modes, one important activities in this program is proactive materials degradation management directed by the author which is a kind of the extension program of NRC PMDA program based upon more fundamental approach by a systematic elicitation by the experts nominated from all over the world. NISA program can be divided into two phases, one is from fiscal years (FY) 2006 - 2010 and the other FY 2011. Later phase is focusing more on System Safety due to Fukushima NPP accident. The main objectives of the Phase I is to evaluate potential and complex degradation phenomena and their mechanisms in order to identify future risks of component aging in nuclear power plants. The following items are of particular concern in this phase: (a) investigation of

  2. 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.

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

    Directory of Open Access Journals (Sweden)

    H. L. Throop

    2012-07-01

    Full Text Available 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 quantitative 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 in the absence of O2 in addition to H2 release in the presence of O2. Our results suggest that abiotic release of H2 during organic matter is ubiquitous in terrestrial ecosystems. We propose that because these processes occur at the soil-atmosphere interface, they provide a previously unaccounted for 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.

  4. 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...

  5. IDENTIFICATION, MOLECULAR CHARACTERIZATION AND EVALUATION OF SOME RUMINAL BACTERIA THAT CATALYZE AND DEGRADE PLANT CELLULOSIC MATERIALS

    Directory of Open Access Journals (Sweden)

    Ahmed A. Mansour

    2014-01-01

    Full Text Available In the last few years there was a growing economic awareness about plant wastes and use it in compost production or in feeding of farm animals, some of these wastes are useless and cause a lot of problems in Egyptian environment. This study was designed to isolate, identify and evaluate some ruminal bacterial isolates to facilitate the in vitro degradation of certain local agro-industrial wastes (rice straw and corn stalks. Two bacterial isolates were isolated from rumen fluid of some Egyptian cattle and identified as Fibrobacter succinogenes and Ruminococcus albus depending on morphological, biochemical identification and molecular characterization using 16S rRNA genes. Two degenerate primers were used to detect about 1.6 kb PCR fragment, a partial sequences (709 and 401 bp were sequenced for F. succinogenes and R. albus respectively. The highest similarity was detected for both isolates which were 57% with Streptomyces sp. for F. succinogenes and 77% with Enterobacter sp. for R. albus. The two isolates were subjected in-vitro to catalyze and degrade rice straw and corn stalks. After four weeks of fermentation, degradation was measured depending on the bacterial growth and changes in chemical components of the degraded materials. The degradation of corn stalks was highly significant comparing to rice straw which inoculated by F. succinogenes or R. albus. Analysis of the chemical composition showed a decrease in Organic Matter (OM, Crude Fiber (CF, Neutral Detergent Fiber (NDF, Acid Detergent Fiber (ADF, cellulose and hemicellulose content. The inoculum 7.5 mL/50 g of Ruminococcus albus is more efficient to degrade rice straw or corn stalks in four weeks fermentation period. Corn stalks are better than rice straw to enhance the cellulolytic bacteria to grow in all treatments.

  6. Building materials as the source of radiation load of Slovak population

    International Nuclear Information System (INIS)

    In the paper are analyzed the measured values of the concentration of natural radionuclides in the most common building materials and given the annual effective doses calculated for the Slovak population living in typical type of dwellings. (author)

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

    International Nuclear Information System (INIS)

    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 238U, 235U and 232Th. 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)

  8. Application of hybrid and moment methods to the measurement of moisture diffusion coefficients of building materials

    Science.gov (United States)

    Delgado, J. M. P. Q.; Ramos, N. M. M.; de Freitas, V. P.

    2011-11-01

    This work proposes two simple dynamic methods that provide an accurate method for measurement of diffusion coefficients in building materials. Experimental measurements of moisture diffusion coefficients covered three commonly used building materials and they were carried out for a range of the relevant parameters, as temperature and relative humidity. The diffusion coefficients obtained by the two dynamic methods show a deviation comparatively to the steady-sate cup method; however, this variance is in accordance with the results presented in literature.

  9. Examination of express determination of 226Ra in buildings materials using gamma spectrometry

    International Nuclear Information System (INIS)

    In the article is presented the proposal of express method for evaluation of radium concentration in building material. The method is based on estimation function of time dependence of achievement of equilibrium radon daughter products radioactivity with the 226Ra. The obtained results from one selected sample of building material (porous concrete brick) show, that estimation of radium concentration on acceptable confidence level is possible obtain during some days. (authors)

  10. Dose assessment from domestic building materials used in housing sector in Serbia

    International Nuclear Information System (INIS)

    The results of mass activity measuring in many domestic building materials used in a housing sector are presented. Natural radionuclides 40K, 226Ra, 232Th, 235U and 238U as well as artificial radionuclide 137Cs were detected using a gamma spectrometry. Based on measured mass activity values, the absorbed dose rate from examined building materials was calculated following EC standards. According to the UNSCEAR procedure, the annual effective dose was also calculated. (authors)

  11. 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

  12. Introduction to the environmental impact of construction and building materials

    OpenAIRE

    Torgal, Fernando Pacheco

    2014-01-01

    “Woodhead Publishing series in civil and structural engineering, nr. 49” Earth's natural resources are finite and face increasing human pressure. Over the last few decades, concern has been growing about resource efficiency and the environmental impact of material consumption. The construction industry is responsible for the consumption of a relevant part of all produced materials, however, only recently has this industry started to worry about its environmental impacts. This chapter highl...

  13. Cost Optimization of Industrial Enterprises of Building Materials

    OpenAIRE

    Belovodskaya Alena A.

    2012-01-01

    The paper has proved that one of the directions of increasing profitability of construction materials industry enterprises’ activity can be optimizing costs dealing with sales. Tools of neuro-linguistic programming (NLP) or so called sensor marketing have been proposed for use to choose the most effective technology of market promoting construction materials. Use of method of solving optimization tasks in mathematical programming has allowed getting a ranked series of NLP measures for decreas...

  14. Local materials for building houses: laterite valorization in Africa

    OpenAIRE

    Lawane, A.; Pantet, Anne; VINAI, Raffaele; Thomassin, Jean-Hugues

    2012-01-01

    This paper presents the preliminary results of geological and geomechanical studies on the laterite stone exploited at Dano quarry in Burkina Faso. The field work described the geological structure of quarry sites and their environment to determine the rocks alteration and the links between the bedrock and lateritic material. Physic-mechanical properties have been studied for assessing the potentiality of this material for lightweight housing, to be completed with thermal and environmental co...

  15. 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.

  16. Experimental simulation of materials degradation of plasma-facing components using lasers

    International Nuclear Information System (INIS)

    The damage and erosion of plasma-facing components (PFCs) due to extremely high heat loads and particle bombardment is a key issue for the nuclear fusion community. Currently high current ion and electron beams are used in laboratories for simulating the behaviour of PFC materials under ITER-like conditions. Our results indicate that high-power nanosecond lasers can be used for laboratory simulation of high heat flux PFC material degradation. We exposed tungsten (W) surfaces with repetitive laser pulses from a nanosecond laser with a power density ∼ a few GW cm−2. Emission spectroscopic analysis showed that plasma features at early times followed by intense particle emission at later times. Analysis of laser-exposed W surface demonstrated cracks and grain structures. Our results indicate that the typical particle emission features from laser-irradiated tungsten are consistent with high-power particle beam simulation results. (letter)

  17. Experimental simulation of materials degradation of plasma-facing components using lasers

    Science.gov (United States)

    Farid, N.; Harilal, S. S.; El-Atwani, O.; Ding, H.; Hassanein, A.

    2014-01-01

    The damage and erosion of plasma-facing components (PFCs) due to extremely high heat loads and particle bombardment is a key issue for the nuclear fusion community. Currently high current ion and electron beams are used in laboratories for simulating the behaviour of PFC materials under ITER-like conditions. Our results indicate that high-power nanosecond lasers can be used for laboratory simulation of high heat flux PFC material degradation. We exposed tungsten (W) surfaces with repetitive laser pulses from a nanosecond laser with a power density ˜ a few GW cm-2. Emission spectroscopic analysis showed that plasma features at early times followed by intense particle emission at later times. Analysis of laser-exposed W surface demonstrated cracks and grain structures. Our results indicate that the typical particle emission features from laser-irradiated tungsten are consistent with high-power particle beam simulation results.

  18. Study of radon exhalation rate from different types of surfaces of building and activity of 226Ra in building materials

    International Nuclear Information System (INIS)

    Radon exhalation rate from different surfaces of ground floor vary from 0.95 -3.2 mBq.m-2.s-1. The average value in the first floor surface is 1.2 mBq.m-2.s-1 and exhalation from walls vary from 0.752 - 3.85 mBq.m-2s-1 and with a bare surface it is 5.49 mBq.m-2.s-1. The activity of 226Ra in building materials is estimated by using emanometer. The activity of 226Ra is low in sand (4.01 Bq.kg-1) and is high for granite (55 Bq.kg-1), and almost same in concrete and brick. The activity of 226 Ra in building materials is low compared to the global average. (author)

  19. 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 f...... microstructure could be optimised for best possible fatigue resistance. These issues areaddressed in the present report, with special emphasis on test methods, and scaling from damage mechanisms to relevant material properties.......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...

  20. Thermal conductivity deg.radation of ceramic materials due to low temperature, low dose neutron irradiation

    International Nuclear Information System (INIS)

    The thermal conductivity degradation due to low-temperature neutron irradiation is studied and quantified in terms of thermal resistance terms. Neutron irradiation is assumed to have no effect on umklapp scattering. A theoretical model is presented to quantify the relative phonon-scattering effectiveness of the three dominant defect types produced by neutron irradiation: point defects, dislocation loops and voids. Several commercial ceramics have been irradiated with fission reactor fast neutrons at low temperatures to produce defects. Materials include silicon carbide, sapphire, polycrystalline alumina, aluminum nitride, silicon nitride, beryllium oxide, and a carbon fiber composite. The neutron dose corresponded to 0.001 and 0.01 displacements per atom (dpa) for a ∼60 deg. C irradiation and 0.01 and 0.1 dpa for a ∼300 deg. C irradiation. Substantial thermal conductivity degradation occurred in all of the materials except BeO following irradiation at 60 deg. C to a dose of only 0.001 dpa. The data are discussed in terms of the effective increase in thermal resistance caused by the different irradiation conditions. Evidence for significant point defect mobility during irradiation at 60 and 300 deg. C was obtained for all of the ceramics. The thermal stability of the radiation defects was investigated by isochronal annealing up to 1050 deg. C

  1. 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.

  2. 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.

  3. Characterization of Finnish Building materials under salt frost artificial ageing

    Science.gov (United States)

    Luodes, Nike M.; Torppa, Akseli; Pirinen, Heikki; Bellopede, Rossana; Marini, Paola

    2016-04-01

    Under a national project co financed by the Confederation of Finnish Construction Industries RT (CFCI), the Finnish Natural Stone Association and the Geological Survey of Finland (GTK), and thanks to the cooperation with the Polytechnic of Turin a comprehensive number of Finnish natural stones has been tested according to SFS EN standards for national CE marking and according to non standardized methods for research purposes. The aim was to evaluate the effects of combined salt and frost weathering caused by de-icing salts and to research a possible correlation between laboratory's accelerated decay and site weathering. The materials tested (60 stones in total) are mainly silicate rocks showing good resistance to the weathering. Results have been affected in some cases by uncertainties connected to the variation of material quality. Some materials have been from new quarries and variation of their properties has been higher than the effects of artificial weathering. Material sampled from crop presented higher weathering level and the additional artificial weathering has induced small variations. Results have shown that material weathering has been better represented by variation of flexural strength compared to uniaxial compressive strength. The most probable reason has been that small changes of planarity and perpendicularity had greater effects on the compressive strength than variations by weathering. Fifteen representative typologies of natural stones have been tested with non standardized methodologies to study the changes of the material and finding a possible correlation with methods used on site. Schmidt rebound test and Ultra Pulse Velocity (UPV) have been used on site to assess the durability of stone on construction. Materials tested in laboratory have shown less variation between rebounds compared to site tests, this can be because of a more controlled environment and saw cut surface instead of rocky or chiselled ones. Laboratory tests showed an average

  4. Measurement of natural radioactivity in common building materials used around the Tiruvannamalai city, Tamilnadu, India

    International Nuclear Information System (INIS)

    Building materials cause direct radiation exposure because of their radium, thorium and potassium content. In this paper, samples of commonly used building materials (bricks, cement, soil, clay and sand) have been collected from Tiruvannamalai city to Pachal of Tiruvannamalai district, Tamilnadu, India. The samples were tested for their radioactivity contents by using gamma spectroscopic measurements. The radiological hazards in the building materials due to the natural radioactivity were inferred from the calculations of radium equivalent activity (Raeq), criteria formula, the indoor gamma absorbed dose rate (DR) air, the annual effective dose (HR), the alpha-index (Iá), gamma-index (Iã), external hazard index (Hex) and the internal radiation hazard index (Hin). These radiological parameters were evaluated and compared with the internationally recommended values. From the analysis, it was found that these materials may be safely used as construction materials and do not pose significant radiation hazard. (author)

  5. BUILDING MATERIALS WITH INSULATING PROPERTIES BASED ON RICE HUSK)

    OpenAIRE

    Salas, J.

    2014-01-01

    [EN]This work within the research projeci "Material, Technologies and Low Cosí Housing Prototypes" has the purpose lo obiain a bu i Id i ng material based on cemení and treated rice husk, for iis use as ihermal insulator The performance of different dosages was analyzed and according to the results two dosages were choosen to make standard panels ofóO X 90 X 6cm which were testedfor bending, and the thermal conductiviiy valúes were determined, valué of\\ which fluciuaie...

  6. Assessment of radiological risk due to natural radioactivity present in some building materials used around Kalpakkam

    International Nuclear Information System (INIS)

    Building materials cause direct radiation exposure because of their uranium, thorium and potassium content. The need for determination of natural radioactivity content in building materials arises from the growing attention paid to its potential radiation effects and consequent concern of many producers of such materials. In this paper around 97 samples of commonly used building materials have been collected randomly around Kalpakkam and analyzed for natural radioactivity due to presence of primordial radionuclide 238U, 232Th and 40K using gamma spectrometry. The activity of different building material obtained in this study ranged from ≤ 3-72 Bq/kg for 238U, ≤ 5-163 Bq/kg for 232Th and ≤ 38-1481 for 40K, respectively. The highest 238U, 232Th and 40K was found in asbestos, red soil and granite, respectively. The minimum values of 238U, 232Th and 40K were found in wood. The radium equivalent activity (Raeq), external hazard index (Hex), internal hazard index (Hin), absorbed dose rate (D) in air, annual effective dose equivalent (Eeff) and activity concentration index (I) were evaluated to assess the radiation hazard for people living in dwelling made of building materials studied. All the building materials showed radium equivalent activity (Raeq) values lower than the limit of 370 Bq/kg set in United Nations Scientific Committee on the Effects of Atomic Radiation Report (UNSCEAR,1988).The resulting annual effective dose equivalent due to total external terrestrial radiation is less than 1 mSv/year. The results presented indicate that commonly used building material in Kalpakkam does not exceed the proposed radioactivity criterion level. (author)

  7. A matrix in life cycle perspective for selecting sustainable materials for buildings in Sri Lanka

    Energy Technology Data Exchange (ETDEWEB)

    Abeysundara, U.G. Yasantha [Ministry of Education, Isurupaya, Battaramulla (Sri Lanka); Babel, Sandhya [Environmental Technology Program, School of Biochemical Engineering and Technology, Sirindhorn International Institute of Technology, Thammasat University, P.O. Box 22, Pathumthani 12121 (Thailand); Gheewala, Shabbir [The Joint Graduate School of Energy and Environment, King Mongkut' s University of Technology Thonburi, Bangkok 10140 (Thailand)

    2009-05-15

    This paper presents a matrix to select sustainable materials for buildings in Sri Lanka, taking into consideration environmental, economic and social assessments of materials in a life cycle perspective. Five building elements, viz., foundations, roofs, ceilings, doors and windows, and floors are analyzed based on materials used for these elements. Environmental burdens associated with these elements are analyzed in terms of embodied energy and environmental impacts such as global warming, acidification and nutrient enrichment. Economic analysis is based on market prices and affordability of materials. Social factors that are taken into account are thermal comfort, interior (aesthetics), ability to construct quickly, strength and durability. By compiling the results of analyses, two building types with minimum and maximum impacts are identified. These two cases along with existing buildings are compared in a matrix of environmental, economic and social scores. Analysis of the results also indicates need for higher consideration of environmental parameters in decision-making over social and economic factors, as social and economic scores do not vary much between cases. Hence, this matrix helps decision-makers to select sustainable materials for buildings, meaningfully, and thus helps to move towards a more sustainable buildings and construction sector. (author)

  8. Environmental impact of steel and concrete as building materials

    OpenAIRE

    Bujnak, Jan

    2011-01-01

    Energy consumption, harmful air emission and natural resource depletion as three environmental concerns are investigated on the prestressed concrete and to equal extend on steel- concrete composite highway bridges. The main results presented in the paper validate clearly advantage of steel as structural material particularly from the point of view of sustainable development.

  9. Fracture of advanced building materials: aspects of modelling

    Czech Academy of Sciences Publication Activity Database

    Veselý, V.; Keršner, Z.; Knésl, Zdeněk

    Roterdam: Millpress, 2007 - (Zingoni, A.), s. 643-649 [International Conference on Structural Engineering, Mechanics and Computation /3./ (SEMC 2007). Cape Town (ZA), 10.09.2007-12.09.2007] Institutional research plan: CEZ:AV0Z20410507 Keywords : cementitious composites * numerical modelling * fracture experiment * fracture energy Subject RIV: JL - Materials Fatigue, Friction Mechanics

  10. 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.

  11. Compostability of Co-Extruded Starch/Poly(Lactic Acid Polymeric Material Degradation in an Activated Inert Solid Medium

    Directory of Open Access Journals (Sweden)

    Alain Copinet

    2009-07-01

    Full Text Available The aim of this work was to estimate the biodegradation of a co-extruded starch/poly(lactic acid polymeric material using a vermiculite based inert solid medium which could simulate compost medium and enable us to achieve complete carbon balances. At the end of the test the mineralisation rate was compared to those obtained for co-extruded starch/poly(lactic acid polymeric material degradation in compost. It was shown that the mineralisation rate after 45 days of degradation was similar in activated vermiculite medium to the one in compost. A protocol for both extraction and quantification of the carbon included in the different degradation by-products was proposed and the carbon balance of the polymer degradation was followed during the test with a satisfactory accuracy. As the non-degraded PLA and starch material had been retrieved during the test, the evolution of the glass transition temperature and the molecular weight of PLA could be followed. A two-step degradation mechanism was highlighted in inert solid medium, showing the fundamental role of abiotic reactions for PLA degradation in compost.

  12. Building up and knocking down: an emerging role for epigenetics and proteasomal degradation in systems consolidation.

    Science.gov (United States)

    Walters, B J; Zovkic, I B

    2015-08-01

    Memory formation is a protracted process in which recently acquired events are consolidated to produce stable and specific associations. Initially, newly acquired information undergoes cellular consolidation in the hippocampus, which transiently supports the storage of recently acquired memories. In contrast, remote, or "old" memories are maintained in the cortex and show almost complete independence from the hippocampus. Memories are transferred from the hippocampus to the cortex through a process termed systems consolidation. Emerging evidence suggests that recurrent activation, or "training" of the cortex by the hippocampus is vital to systems consolidation. This process involves prolonged waves of memory-related gene activity in the hippocampus and cortex long after the learning event has terminated. Indeed, molecular events occurring within hours and days of fear conditioning are essential for stabilizing and eventually transitioning the memory to the cortex. It is increasingly evident that molecular mechanisms that exhibit a capacity for prolonged activation may underlie systems consolidation. Processes that have the capacity to control protein abundance over long time scales, such as epigenetic modifications, are prime candidates for the molecular mechanism of systems consolidation. Indeed, recent work has established two types of epigenetic modifications as integral for systems consolidation. First, localized nucleosomal histone variant exchange and histone modifications are integral for early stages of systems consolidation, whereas DNA methylation appears to be utilized to form stable marks that support memory maintenance. Since systems consolidation also requires discrete and time-sensitive changes in protein abundance, additional mechanisms, such as protein degradation, need also be considered, although their role in systems consolidation has yet to be investigated. Here, we discuss the role of molecular mechanisms in systems consolidation and their

  13. 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.

  14. 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.

  15. Multivariate statistical analysis of radiological data of building materials used in Tiruvannamalai, Tamilnadu, India.

    Science.gov (United States)

    Ravisankar, R; Vanasundari, K; Suganya, M; Raghu, Y; Rajalakshmi, A; Chandrasekaran, A; Sivakumar, S; Chandramohan, J; Vijayagopal, P; Venkatraman, B

    2014-02-01

    Using γ spectrometry, the concentration of the naturally occurring radionuclides (226)Ra, (232)Th and (40)K has been measured in soil, sand, cement, clay and bricks, which are used as building materials in Tiruvannamalai, Tamilnadu, India. The radium equivalent activity (Raeq), the criterion formula (CF), indoor gamma absorbed dose rate (DR), annual effective dose (HR), activity utilization index (AUI), alpha index (Iα), gamma index (Iγ), external radiation hazard index (Hex), internal radiation hazard index (Hin), representative level index (RLI), excess lifetime cancer risk (ELCR) and annual gonadal dose equivalent (AGDE) associated with the natural radionuclides are calculated to assess the radiation hazard of the natural radioactivity in the building materials. From the analysis, it is found that these materials used for the construction of dwellings are safe for the inhabitants. The radiological data were processed using multivariate statistical methods to determine the similarities and correlation among the various samples. The frequency distributions for all radionuclides were analyzed. The data set consisted of 15 measured variables. The Pearson correlation coefficient reveals that the (226)Ra distribution in building materials is controlled by the variation of the (40)K concentration. Principal component analysis (PCA) yields a two-component representation of the acquired data from the building materials in Tiruvannamalai, wherein 94.9% of the total variance is explained. The resulting dendrogram of hierarchical cluster analysis (HCA) classified the 30 building materials into four major groups using 15 variables. PMID:24412972

  16. 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.

  17. A metric for characterizing the effectiveness of thermal mass in building materials

    International Nuclear Information System (INIS)

    Highlights: • Proposes a metric for interior thermal mass materials (floors, walls, counters). • Simple, yet effective, metric composed of easily calculated ‘local’ and ‘global’ variables. • Like Energy Star, the proposed metric gives a single number to aid consumer choice. • The metric is calculated and compared for selected, readily available data. • Drywall, concrete flooring, and wood paneling are quite effective thermal mass. - Abstract: Building energy use represents approximately 25% of the average total global energy consumption (for both residential and commercial buildings). Heating, ventilation, and air conditioning (HVAC) – in most climates – embodies the single largest draw inside our buildings. In many countries around the world a concerted effort is being made towards retrofitting existing buildings to improve energy efficiency. Better windows, insulation, and ducting can make drastic differences in the energy consumption of a building HVAC system. Even with these improvements, HVAC systems are still required to compensate for daily and seasonal temperature swings of the surrounding environment. Thermal mass inside the thermal envelope can help to alleviate these swings. While it is possible to add specialty thermal mass products to buildings for this purpose, commercial uptake of these products is low. Common building interior building materials (e.g. flooring, walls, countertops) are often overlooked as thermal mass products, but herein we propose and analyze non-dimensional metrics for the ‘benefit’ of selected commonly available products. It was found that location-specific variables (climate, electricity price, material price, insolation) can have more than an order of magnitude influence in the calculated metrics for the same building material. Overall, this paper provides guidance on the most significant contributors to indoor thermal mass, and presents a builder- and consumer-friendly metric to inform decisions about

  18. A new accurate and flexible index to assess the contribution of building materials to indoor gamma exposure

    International Nuclear Information System (INIS)

    The role of building materials as a source of gamma radiation has been recognized in the new EU Basic Safety Standards Directive which introduces an index I to screen building materials of radiological concern. This index was developed to account for average concrete values of thickness and density, the main structural characteristics of building materials that have an effect on gamma irradiation. Consequently, this screening procedure could be unfit in case of significantly different density and/or thickness of the building materials under examination. The paper proposes a more accurate and flexible activity concentration index, accounting for the actual density and thickness of building materials. - Highlights: • Overview of natural radioactivity in industrial residues used in building material. • Estimation of the radiological impact of residues by RP112 index I and room models. • Estimation of building material contribution to the indoor dose by ISS room model

  19. 32 CFR 644.478 - Demolition of buildings and other improvements for utilization of salvage material.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Demolition of buildings and other improvements for utilization of salvage material. 644.478 Section 644.478 National Defense Department of Defense... improvements for utilization of salvage material. With respect to DA property, demolition may be undertaken...

  20. 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

  1. Radon diffusion studies through some building materials: Effect of grain size

    International Nuclear Information System (INIS)

    Radon appears mainly by diffusion processes from the point of origin following α-decay of 226Ra in underground soil and building materials used, in the construction of floors, walls, and ceilings. The diffusion of radon in dwellings is a process determined by the radon concentration gradient across the building material structure between the radon source and the surrounding air, and can be a significant contributor to indoor radon inflow. In the present study radon diffusion through some building materials, viz., soil, sand, fly ash, cement, etc. has been carried out using LR-115 type II solid-state nuclear track detectors (SSNTDs). The radon diffusion coefficients and diffusion lengths through these building construction materials have been calculated. As the rate of radon inflow is dependent upon the porosity and grain size of the materials also, therefore, the effects of grain size on radon diffusion through some of these materials have also been studied. For these studies the materials with different grain sizes, viz. 50, 100, 200μm were used. The results indicate that the radon diffusion through these materials decreases with decrease in grain size

  2. Occurrence of odorous compounds in the emission of building materials measured by GC-olfactometry

    OpenAIRE

    Ramalho, Olivier; Moularat, Stéphane; Horn, Wolfgang; Knudsen, Henrik; WARGOCKI Pawel; Muller, Birgit

    2009-01-01

    In order to identify the most frequent odorous compounds associated with indoor background odour, the static headspace of 16 building material samples (painted and unpainted gypsum boards, wood boards, linoleum and vinyl flooring materials, carpets and sealants) has been characterized by gas chromatography - olfactometry.

  3. Analysis of Actinobacteria from mould-colonized water damaged building material

    OpenAIRE

    Schäfer, Jenny; Jäckel, Udo; Kämpfer, Peter

    2010-01-01

    Mould-colonized water damaged building materials are frequently co-colonized by actinomycetes. Here, we report the results of the analyses of Actinobacteria on different wall materials from water damaged buildings obtained by both cultivation-dependent and cultivation-independent methods. Actinobacteria were detected in all but one of the investigated materials by both methods. The detected concentrations of Actinobacteria ranged between 1.8 x 10(4) and 7.6 x 10(7) CFUg(-1) of investigated ma...

  4. Lunar building materials: Some considerations on the use of inorganic polymers. [adhesives, coatings, and binders

    Science.gov (United States)

    Lee, S. M.

    1979-01-01

    The use of inorganic polymer systems synthesized from the available lunar chemical elements, viz., silicon, aluminum, and oxygen to make adhesives, binders, and sealants needed in the fabrication of lunar building materials and the assembly of structures is considered. Inorganic polymer systems, their background, status, and shortcomings, and the use of network polymers as a possible approach to synthesis are examined as well as glassy metals for unusual structural strength, and the use of cold-mold materials as well as foam-sintered lunar silicates for lightweight shielding and structural building materials.

  5. Nest-building males trade off material collection costs with territory value

    OpenAIRE

    Bailey, Ida E.; Morgan, Kate V.; Oschadleus, H. Dieter; DeRuiter, Stacy L; Meddle, Simone L.; Healy, Susan D.

    2016-01-01

    This work was supported by the BBSRC (BB/I019502/1 to SDH and SLM) and Roslin Institute Strategic Grant funding from the BBSRC (SLM). Building a structurally robust nest is crucial for reproductive success in many birds. However, we know little about the criteria birds use to select material or where they go to collect it. Here we observed the material collection of male Cape Weavers (Ploceus capensis). Males typically selected long, strong material to build their nests and each male colle...

  6. Experimental study of dynamic effects in moisture transfer in building materials

    DEFF Research Database (Denmark)

    Janssen, Hans; Scheffler, Gregor Albrecht; Plagge, Rudolf

    2016-01-01

    of the moisture transfer processes involved. The available evidence primarily stems from imbibition and drainage experiments on soils however, and compared to many other porous media, these tests consider rather permeable materials with relatively dominant liquid transport at comparatively large (de...... building materials. Drying and ad-/desorption tests are executed on two building materials, in which moisture contents and moisture potentials are measured simultaneously. These are translated into dynamic retention relations and dynamic storage coefficients, which both distinctly demonstrate that moisture...... transfer in building materials, similar to moisture transfer in soils, is not free of dynamic effects. The findings imply that the widely accepted static theory for moisture storage in porous media is not generally valid and should be corrected for the occurrences of dynamic effects. Considering that such...

  7. Identification and Assessment of Material Models for Age-Related Degradation of Structures and Passive Components in Nuclear Power Plants

    International Nuclear Information System (INIS)

    This report 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

  8. 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).

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

    OpenAIRE

    R. G. Popa; L. G. Popescu; T. A. Abagiu; Popescu, C.; Cazalbasu, R.

    2015-01-01

    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 partic...

  10. 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.

  11. A New European COST Network 'NORM4Building' (TU1301) for the Reuse of NORM Containing Residues in Building Materials

    International Nuclear Information System (INIS)

    The new COST action was initiated on the 1st of January 2014 and runs for four years. COST is supported by the EU RTD Framework Program. In the presentation more information on how to participate in the network will be provided. In the presentation the new approach and new initiatives of the NORM4BUILDING network, that has its first meeting here in the DEAD SEA Hotel on the 12-13/02/2014, will be introduced. The NORM4Building materials network will be an open network of researchers. An Advisory Board consisting mainly from NORM processing and construction industries and relevant associations and regulators are invited to work in collaboration with the scientists that will populate the various working groups and the management committee of the new COST action

  12. Technical and management challenges associated with structural materials degradation in nuclear reactors in the future

    International Nuclear Information System (INIS)

    There are active plans worldwide to increase nuclear power production by significant amounts. In the near term (i.e. by 2020) this will be accomplished by, (a) increasing the power output of the existing reactors and extending their life, and by, (b) constructing new reactors that are very similar to the current water-cooled designs. Beyond 2025-2030, it is possible that new reactors (i.e. the 'GEN IV' designs) will be very different from those currently in service. A full discussion of the technical and management concerns associated with materials degradation that might arise over the next 40 years would need to address a wide range of topics. Quite apart from discussing the structural integrity issues for the materials of construction and the fuel cladding, the debate would also need to cover, for example, fuel resources and the associated issues of fuel cycle management and waste disposal, manufacturing capacity, inspection capabilities, human reliability, etc., since these all impact to one degree or another on the choice of material and the reactor operating conditions. For brevity, the scope of this article is confined to the integrity of the materials of construction for passive components in the current water-cooled reactors and the evolutionary designs (which will dominate the near term new constructions), and the very different GEN IV reactor designs. In all cases the operating environments will be more aggressive than currently encountered. For instance, the concerns for flow accelerated corrosion and flow-induced vibration will be increased under extended power uprate conditions for the current water-cooled reactors. Of greater concern, the design life will be at least 60 years for all of the new reactors and for those current reactors operating with extended licenses. This automatically presents challenges with regard to managing both irradiation damage in metallic and non-metallic materials of construction, and environmentally assisted cracking. This

  13. 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.

  14. 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)

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

    International Nuclear Information System (INIS)

    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)

  16. Survey of degradation modes of candidate materials for high-level radioactive-waste disposal containers

    International Nuclear Information System (INIS)

    Three copper-based alloys, CDA 102 (oxygen-free, high-purity copper), CDA 613 (aluminum bronze), and CDA 715 (Cu-30Ni), are candidates for the fabrication of high-level radioactive-waste disposal containers. Waste will include spent fuel assemblies from reactors as well as borosilicate glass, and will be sent to the prospective repository site at Yucca Mountain in Nye County, Nevada. The decay of radionuclides will result in the generation of substantial heat and in fluxes of gamma radiation outside the containers. In this environment, container materials might degrade by atmospheric oxidation, general aqueous phase corrosion, localized corrosion (LC), and stress corrosion cracking (SCC). This volume is a critical survey of available data on pitting and crevice corrosion of the copper-based candidates. Pitting and crevice corrosion are two of the most common forms of LC of these materials. Data on the SCC of these alloys is surveyed in Volume 4. Pitting usually occurs in water that contains low concentrations of bicarbonate and chloride anions, such as water from Well J-13 at the Nevada Test Site. Consequently, this mode of degradation might occur in the repository environment. Though few quantitative data on LC were found, a tentative ranking based on pitting corrosion, local dealloying, crevice corrosion, and biofouling is presented. CDA 102 performs well in the categories of pitting corrosion, local dealloying, and biofouling, but susceptibility to crevice corrosion diminishes its attractiveness as a candidate. The cupronickel alloy, CDA 715, probably has the best overall resistance to such localized forms of attack. 123 refs., 11 figs., 3 tabs

  17. Assessment of natural radioactivity and the associated hazards in building materials used in Polur, Tiruvannamalai dist, Tamilnadu, India

    International Nuclear Information System (INIS)

    All building materials are mostly composed of rock and soil and these two raw materials contain natural radioactive isotopes such as 232Th and 226Ra (of 238U) decay series and 40K. Determination of population exposure to radiation from building materials is of great importance, since people spend about 80% of their life inside the buildings. In this study, the activity concentration of natural radionuclides in five important types of building materials, which are most widely used in buildings of Polur, Tiruvannamalai district, Tamilnadu were measured using gamma spectrometry. The hazard indices were calculated from activity concentrations of 226Ra, 232Th and 40K

  18. Estimation of the radon dose in buildings by measuring the exhalation rate from building materials

    International Nuclear Information System (INIS)

    We review the accumulator technique using active (CRM) and passive detectors (activated charcoal and electret). We describe the ERS2 detector, an electrostatic radon sampler followed by alpha spectrometry, with improved algorithm and adapted to measure the exhalation rate from walls. The technique produces accurate results over a broad range of materials: concrete, Pumice, ceramics, tiles, granite, etc. The measured exhalation rate is the same, within errors, as measured by the standard detectors

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

    International Nuclear Information System (INIS)

    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

  20. 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.

  1. Application of Nanotechnology-Based Thermal Insulation Materials in Building Construction

    OpenAIRE

    Bozsaky David

    2016-01-01

    Nanotechnology-based materials have previously been used by space research, pharmaceuticals and electronics, but in the last decade several nanotechnology-based thermal insulation materials have appeared in building industry. Nowadays they only feature in a narrow range of practice, but they offer many potential applications. These options are unknown to most architects, who may simply be afraid of these materials owing to the incomplete and often contradictory special literature. Therefore, ...

  2. Building methodology of virtual laboratory posts for materials science virtual laboratory purposes

    OpenAIRE

    R. Honysz; L.A. Dobrzański

    2007-01-01

    Purpose: The purpose of this article is to describe the building methodology of virtual laboratory posts placed in Material Science Virtual Laboratory. Presented laboratory is an open scientific, investigative, simulating and didactic medium helpful in the realization of the didactic and educational tasks from the field of material engineering in Institute of Engineering Materials and Biomaterials of the Silesian University of Technology in Gliwice, Poland.Design/methodology/approach: The us...

  3. Preparation of insulating material for building applications through freeze-drying method

    OpenAIRE

    Valverde Palomino, José Luis; Simón Herrero, Carolina; Caminero Huertas, Silvia; Romero Izquierdo, Amaya; Sánchez Silva, María Luz

    2015-01-01

    Aerogels are materials with a great porosity, a very low density and a high surfase area. Furhermore, aerogels have the lowest thermal conductivity of any known solid. This characteristic allows to the material to use it as building insulation. In addition, carbonaceous nanomaterials such as carbon nanofibers (CNFs) are added to improve the mechanical resistance of these interesting materials. These nanomaterials exhibit exceptional physical and mechanical properties. The development of na...

  4. Effective density and mass attenuation coefficient for building material in Brazil

    OpenAIRE

    Salinas, I. C. P.; Conti, C. C.; Lopes, R. T.

    2006-01-01

    This paper presents values for density and mass attenuation coefficient of building materials commonly used in Brazil. Transmission measurements were performed to provide input information for simulations with MCNP4B code. The structure for the clay bricks was simulated as a mix of all material layers and an effective density determined. The mass attenuation coefficients were determined for the 50-3000 keV gamma-ray energy range. A comparison with results for similar materials found in the li...

  5. Optimum Installation of Sorptive Building Materials Using Contribution Ratio of Pollution Source for Improvement of Indoor Air Quality.

    Science.gov (United States)

    Park, Seonghyun; Seo, Janghoo

    2016-01-01

    Reinforcing the insulation and airtightness of buildings and the use of building materials containing new chemical substances have caused indoor air quality problems. Use of sorptive building materials along with removal of pollutants, constant ventilation, bake-out, etc. are gaining attention in Korea and Japan as methods for improving such indoor air quality problems. On the other hand, sorptive building materials are considered a passive method of reducing the concentration of pollutants, and their application should be reviewed in the early stages. Thus, in this research, activated carbon was prepared as a sorptive building material. Then, computational fluid dynamics (CFD) was conducted, and a method for optimal installation of sorptive building materials was derived according to the indoor environment using the contribution ratio of pollution source (CRP) index. The results show that a method for optimal installation of sorptive building materials can be derived by predicting the contribution ratio of pollutant sources according to the CRP index. PMID:27043605

  6. 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

  7. 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.

  8. Review of international normatives for natural radioactivity determination in building materials

    OpenAIRE

    Mossini Eros; Macerata Elena; Giola Marco; Mariani Mario

    2015-01-01

    Anthropogenic activities, such as high-altitude flights and living in buildings, have enhanced the public exposure to natural radiation. In particular, 40K and radionuclides belonging to 232Th and 238U decay chains are present even in building materials, and they may be considered as partially responsible for the effective dose coming from natural radioactivity. Scientists and governments have devoted great attention to the evaluation of the effects produced on the public by naturally occurri...

  9. Infrared emissivity measurements of building and civil engineering materials: a new device for measuring emissivity

    OpenAIRE

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

    2014-01-01

    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...

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

    OpenAIRE

    Yoon-Bok Seong; Jae-Han Lim

    2013-01-01

    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...

  11. Old materials and techniques to improve the durability of earth buildings

    OpenAIRE

    Camões, Aires; Eires, R.; Jalali, Said

    2012-01-01

    Quite a big part of the world’s heritage is still made by earth constructions. The durability of the existent heritage, as well as the new earth buildings is particularly conditioned by erosion caused by water action, especially in countries with high rainfall index. With this research one intends to value the ancient knowledge in order to allow higher durability. Analysing the old building techniques to protect the earth material from the water action it is possible to understand how ear...

  12. 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.

  13. γ-ray attenuation coefficient and dose buildup factor of various building materials

    International Nuclear Information System (INIS)

    The present paper describes the γ-ray attenuation coefficient and the dose buildup factor of various building materials, which are of great importance for estimation of the shielding effect of residential houses against γ-rays. The linear attenuation coefficients were measured for 19 building materials with γ-rays and filtered X-rays at energies ranging 44 - 1,250 keV. A corresponding atomic number, Zcor, was defined as an atomic number of the element having the mass attenuation coefficients akin to those of the material. According to Zcor, materials were classified into two groups: one is Zcor = 7 - 9 and the other is Zcor = 13 - 16. The dose buildup factors were measured for 4 materials selected from each material group with γ-rays and filtered X-rays at energies ranging 68 - 1,250 keV. It was found for the thin materials such as ordinary building materials, that the dose buildup factor could be represented approximately by the linear formula, BD = 1 + αμt, and α was characterized by both γ-ray energy and material group. (author)

  14. Engaging degradation mechanisms of materials in a tourney. An investigation into the philosophy of material selection as a mitigating measure and strategy

    OpenAIRE

    Narasimhavarman, Arasilangkumari

    2014-01-01

    The aim of this project is to compare some important factors such as safety and environmental aspects, life cycle costing, reliability, availability and fabrication for selecting materials for flowlines for comparative study between carbon steel as a current practice with respect to various corrosion resistance alloys as an alternatives. In order to do that it is necessary to address all possible degradation mechanisms and the conditions that intensify the degradation process with respect to ...

  15. Building Techniques and Materials in Ancient and Medieval Milan

    Directory of Open Access Journals (Sweden)

    Paola Greppi

    2015-06-01

    Full Text Available The city of Milan preserve an amazing historical and architectural heritage, consisting of a high number of ancient churches, in most cases built to the origins of Christianity and transformed into new form during the Romanesque. In the article are synthetically presented the results of the research work of the writer about construction techniques of the most important churches in the city (S. Ambrogio, S. Simpliciano, S. Giovanni alle Fonti, S. Nazaro Maggiore, ..., trying to highlight the main changes between Late Antiquity and Romanesque. A large amount of stone material were used in Roman architecture of Milan and Lombardy, thanks to the geological variety of the territory. The Alps supplied granites, diorites, gneisses and marbles; the Prealps supplied limestones, dolomites, sandstones (Mesozoic and conglomerates (Quaternary; the Padània alluvial plain supplied pebbles, gravels, sands and clays (Quaternary. Each stone had a local use reaching the nearest towns (Como, Pavia, Milan, Bergamo, Brescia through waterways; the towns of the plain (Piacenza, Cremona, Mantua employed bricks made of local clay. Milano, the capital, employed also stones coming from abroad (limestones from Venetia and Friuli. White marbles of Apuanian Alps and coloured marbles of Eastern mediterranean were also diffused in Milan and other Lombard sites despite the laborious supplying. The stones quarried by the Romans were continuously used in the following centuries.

  16. Microstructure and microanalysis of some ancient building materials

    International Nuclear Information System (INIS)

    In order to assess the very long term of durability of modern Portland cements for encapsulating certain types of radioactive waste, the microstructure and microanalysis of concretes of various ages made from such cements are compared with those from similar materials of ancient origins with ages upto 2500 years used in early Greek, Roman and British Construction. Most of the historical 'concretes' examined were heavily carbonated and at best showed only traces of the calcium silicate hydrate (C-S-H) phase, the heart of modern Portland Cement concretes. The notable exception was the 1700 years old concrete from Hadrian's Wall - the mortar in this was rich in C-S-H. The modern concrete samples, from 10 to 140 years old, showed little carbonation and their compositions of the C-S-H phase were very similar to those found from Hadrian's Wall. From all the evidence examined, it is concluded that the C-S-H phase is capable of surviving intact for several thousands of years in the absence of external chemical attack. (author)

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

    Science.gov (United States)

    Górny, Rafał L.; Reponen, Tiina; Grinshpun, Sergey A.; Willeke, Klaus

    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 -2 from surfaces 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 at a frequency of 1 Hz at a power level of 14 W 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 10 min.

  18. Measurement of natural radioactivity in building materials of Namakkal, Tamil Nadu, India using gamma-ray spectrometry

    International Nuclear Information System (INIS)

    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 226Ra, 232Th and 40K 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. - Highlights: ► Most of the building materials contain natural radionuclides. ► The radioactivity level in building materials is used to assess the radiological hazards to human. ► We present the results for the measured activities and radiation hazards of building materials. ► We report that the studied building materials do not pose any significant radiation hazard.

  19. Building materials as the source of radiation load of Slovak population

    International Nuclear Information System (INIS)

    In the paper are analyzed the measured values of the concentration of natural radionuclides in the most common building materials and given the annual effective doses calculated for the Slovak population living in typical type of dwellings. The comparison of our results with the data published in several European countries (Germany, Sweden, UK, Ireland, Greece ) have shown, that the Slovak values of annual effective doses from extemal radiation are in the lower part of the range of radiation load of European population represented by (0.78 -1,6) for brick and (0.68 -1.,0) mSv/y for concrete. The annual effective dose for Slovak inhabitant estimated in brick dwellings is 0.87 mSv/y and in concrete buildings is 0.31 mSv/y. The concentration of natural radioactivity noted in Slovak building materials suggest, that these materials will not cause significant contribution to radiation exposure. (authors)

  20. 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 of the......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 5x30x30cm"3 . Numerical modelling is used to assess...... specific applications of the investigated building materials, the contribution to the indoor radon-222concentration 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...

  1. Atmospheric methane removal by methane-oxidizing bacteria immobilized on porous building materials.

    Science.gov (United States)

    Ganendra, Giovanni; De Muynck, Willem; Ho, Adrian; Hoefman, Sven; De Vos, Paul; Boeckx, Pascal; Boon, Nico

    2014-04-01

    Biological treatment using methane-oxidizing bacteria (MOB) immobilized on six porous carrier materials have been used to mitigate methane emission. Experiments were performed with different MOB inoculated in building materials at high (~20 % (v/v)) and low (~100 ppmv) methane mixing ratios. Methylocystis parvus in autoclaved aerated concrete (AAC) exhibited the highest methane removal rate at high (28.5 ± 3.8 μg CH₄ g⁻¹ building material h⁻¹) and low (1.7 ± 0.4 μg CH₄ g⁻¹ building material h⁻¹) methane mixing ratio. Due to the higher volume of pores with diameter >5 μm compared to other materials tested, AAC was able to adsorb more bacteria which might explain for the higher methane removal observed. The total methane and carbon dioxide-carbon in the headspace was decreased for 65.2 ± 10.9 % when M. parvus in Ytong was incubated for 100 h. This study showed that immobilized MOB on building materials could be used to remove methane from the air and also act as carbon sink. PMID:24337222

  2. A Protocol for Lifetime Energy and Environmental Impact Assessment of Building Insulation Materials

    Energy Technology Data Exchange (ETDEWEB)

    Shrestha, Som S [ORNL; Biswas, Kaushik [ORNL; Desjarlais, Andre Omer [ORNL

    2014-01-01

    This article describes a proposed protocol that is intended to provide a comprehensive list of factors to be considered in evaluating the direct and indirect environmental impacts of building insulation materials, as well as detailed descriptions of standardized calculation methodologies to determine those impacts. The energy and environmental impacts of insulation materials can generally be divided into two categories: (1) direct impact due to the embodied energy of the insulation materials and other factors, and (2) indirect or environmental impacts avoided as a result of reduced building energy use due to addition of insulation. Standards and product category rules exist that provide guidelines about the life cycle assessment (LCA) of materials, including building insulation products. However, critical reviews have suggested that these standards fail to provide complete guidance to LCA studies and suffer from ambiguities regarding the determination of the environmental impacts of building insulation and other products. The focus of the assessment protocol described here is to identify all factors that contribute to the total energy and environmental impacts of different insulation products and, more importantly, provide standardized determination methods that will allow comparison of different insulation material types. Further, the intent is not to replace current LCA standards but to provide a well-defined, easy-to-use comparison method for insulation materials using existing LCA guidelines.

  3. Chemical physics analysis for building materials of Bangunan Panggung Drama Jalan Bandar Kuala Lumpur Malaysia: a case study

    International Nuclear Information System (INIS)

    The paper discussed the studies carried-out using XRD, x-ray diffraction technique on the historical building materials i.e. mortars, paints, concretes - Panggung Drama - old theatre stage building located at Jalan Bandar, Kuala Lumpur, Malaysia

  4. Survey of degradation modes of candidate materials for high-level radioactive-waste disposal containers

    International Nuclear Information System (INIS)

    Six alloys are being considered as possible materials for the fabrication of containers for the disposal of high-level radioactive waste. Three of these candidate materials are copper-based alloys: CDA 102 (oxygen-free copper), CDA 613 (Cu-7Al), and CDA 715 (Cu-30Ni). The other three are iron- to nickel-based austenitic materials: Types 304L and 316L stainless steels and Alloy 825. Radioactive waste will include spent-fuel assemblies from reactors as well as waste in borosilicate glass and will be sent to the prospective site at Yucca Mountain, Nevada, for disposal. The waste-package 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, the containers must be retrievable from the disposal site. Shortly after emplacement of the containers in the repository, they will be exposed to high temperatures and high gamma radiation fields from the decay of high-level waste. This radiation will promote the radiolytic decomposition of moist air to hydrogen. This volume surveys the available data on the effects of hydrogen on the six candidate alloys for fabrication of the containers. For copper, the mechanism of hydrogen embrittlement is discussed, and the effects of hydrogen on the mechanical properties of the copper-based alloys are reviewed. The solubilities and diffusivities of hydrogen are documented for these alloys. For the austenitic materials, the degradation of mechanical properties by hydrogen is documented. The diffusivity and solubility of hydrogen in these alloys are also presented. For the copper-based alloys, the ranking according to resistance to detrimental effects of hydrogen is: CDA 715 (best) > CDA 613 > CDA 102 (worst). For the austenitic alloys, the ranking is: Type 316L stainless steel ∼ Alloy 825 > Type 304L stainless steel (worst). 87 refs., 19 figs., 8 tabs

  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

    Six alloys are being considered as possible materials for the fabrication of containers for the disposal of high-level radioactive waste. Three of these candidate materials are copper-based alloys: CDA 102 (oxygen-free copper), CDA 613 (Cu-7Al), and CDA 715 (Cu-30Ni). The other three are iron- to nickel-based austenitic materials: Types 304L and 316L stainless steels and Alloy 825. Radioactive waste will include spent-fuel assemblies from reactors as well as waste in borosilicate glass and will be sent to the prospective site at Yucca Mountain, Nevada, for disposal. The waste-package 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, the containers must be retrievable from the disposal site. Shortly after emplacement of the containers in the repository, they will be exposed to high temperatures and high gamma radiation fields from the decay of high-level waste. This radiation will promote the radiolytic decomposition of moist air to hydrogen. This volume surveys the available data on the effects of hydrogen on the six candidate alloys for fabrication of the containers. For copper, the mechanism of hydrogen embrittlement is discussed, and the effects of hydrogen on the mechanical properties of the copper-based alloys are reviewed. The solubilities and diffusivities of hydrogen are documented for these alloys. For the austenitic materials, the degradation of mechanical properties by hydrogen is documented. The diffusivity and solubility of hydrogen in these alloys are also presented. For the copper-based alloys, the ranking according to resistance to detrimental effects of hydrogen is: CDA 715 (best) > CDA 613 > CDA 102 (worst). For the austenitic alloys, the ranking is: Type 316L stainless steel {approx} Alloy 825 > Type 304L stainless steel (worst). 87 refs., 19 figs., 8 tabs.

  6. Application of Nanotechnology-Based Thermal Insulation Materials in Building Construction

    Science.gov (United States)

    Bozsaky, David

    2016-03-01

    Nanotechnology-based materials have previously been used by space research, pharmaceuticals and electronics, but in the last decade several nanotechnology-based thermal insulation materials have appeared in building industry. Nowadays they only feature in a narrow range of practice, but they offer many potential applications. These options are unknown to most architects, who may simply be afraid of these materials owing to the incomplete and often contradictory special literature. Therefore, they are distrustful and prefer to apply the usual and conventional technologies. This article is intended to provide basic information about nanotechnology-based thermal insulation materials for designers. It describes their most important material properties, functional principles, applications, and potential usage options in building construction.

  7. Dielectric Characterization of composite building materials depending on the volume fraction for Mobile Phone Frequencies

    Directory of Open Access Journals (Sweden)

    Terhzaz Jaouad

    2014-04-01

    Full Text Available This W presents a new technique of Dielectric Characterization of composites building materials. This technique is based on the modeling of an open coaxial cell with a mathematical formulation that links the admittances of the filled and empty cell to the complex permittivity ε* of materials characterization. We applied this technique to the dielectric characterization of some building materials powder in the frequency band (100MHz-4GHz. We also characterize some composite materials (sand- brick, cement- sand, and cement-brick depending on the volume fraction for Mobile Phone Frequencies. We made a comparison with the laws of mixtures to identify the most appropriate law to render the dielectric behavior of these materials.

  8. 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.

  9. Effect of moisture on radon exhalation rate of the building material bricks

    International Nuclear Information System (INIS)

    In the paper, The moisture of building material bricks was controlled by the saturation solution of inorganic salt which were deposited in a obturator. The activated charcoal method was used to compare the influence of radon exhalation rate of building material bricks on different moistures condition. From the result, it can be found that with the increasing of mositure, the radon exhalation rate is increasing at first and then discreasing, when the mositure is about 4%, and the highest radon exhalation rate is 32.31 ± 2.84mBq. m-2.s-1. (authors)

  10. Thorium determination in intercomparison samples and in some Romanian building materials by gamma ray spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Pantelica, A.; Georgesecu, I.I.; Murariu-Magureanu, M.D.; Margaritescu, I.; Cincu, E

    2001-07-01

    Thorium content in zircon sand, thorium ore and thorium liquid sample (EU Laboratories Network Intercomparison), as well as in some Romanian building materials: sand, wood, tufa, asbestos-cement, cement mill dust, coal fly ash, bricks, and tile (28 samples) were determined by gamma ray spectrometry. For the building materials, {sup 226}Ra, {sup 40}K and {sup 137}Cs specific activities were also measured. The results were compared with the Romanian legal norms concerning the highest admissible levels for {sup 232}Th, {sup 226}Ra, and {sup 40}K radioactivity, and to Th, U, and K concentration values previously determined in our laboratory on similar types of samples. (author)

  11. Thorium determination in intercomparison samples and in some Romanian building materials by gamma ray spectrometry

    International Nuclear Information System (INIS)

    Thorium content in zircon sand, thorium ore and thorium liquid sample (EU Laboratories Network Intercomparison), as well as in some Romanian building materials: sand, wood, tufa, asbestos-cement, cement mill dust, coal fly ash, bricks, and tile (28 samples) were determined by gamma ray spectrometry. For the building materials, 226Ra, 40K and 137Cs specific activities were also measured. The results were compared with the Romanian legal norms concerning the highest admissible levels for 232Th, 226Ra, and 40K radioactivity, and to Th, U, and K concentration values previously determined in our laboratory on similar types of samples. (author)

  12. Measurement of Rn-222 concentrations in building materials used in jordan

    International Nuclear Information System (INIS)

    In this work, the concentrations of the radiative inert gas Rn-222 emanated from the building materials that are commonly in jordan have been studied. For this purpose, samples of ten jordanian building materials of different masses were prepared in plastic cans sealed to passive integrated dosimeters containing CR-39 solid state nuclear track detectors which are very sensitive to alpha-particles. The Rn-222 concentrations in these samples range from 137 Bq/m3 to 267 Bq/m3 with an average of 189 Bq/m3. These levels were found to be consistent with those measured by other workers in other countries. 4 figs., 2 tabs

  13. Radionuclide content in some building materials in Syria and their indoor gamma dose rate

    International Nuclear Information System (INIS)

    Radionuclide contents of materials used in the cement industry and natural raw building materials in Syria have been determined by gamma spectrometry. Samples crushed and counted in Marinelli beakers bricks, ceramic, fireclay and phosphogypsum showed higher levels of radioactivity. Sand, cement, marble and limestone contained lower values. All samples fulfilled the criteria set up by OECD except the phosphogypsum. The absorbed gamma dose rate in indoor air was estimated to be 25.2 nGy.h-1: this value has been corrected for build-up, windows and door factors. (author)

  14. Radionuclide content in some building materials in Syria and their indoor gamma dose rate

    International Nuclear Information System (INIS)

    Radionuclide contents of materials used in cement industry and natural raw building materials in Syria have been determined by gamma spectrometry. Samples crushed and counted in Marinelli beakers Bricks, ceramic, fireclay and phosphogypsum did show higher levels of radioactivity. Sand, cement marble and limestone contained lower values. All samples fulfilled the criteria set up by OECD except the phosphogypsum. The absorbed gamma dose rate indoor air was estimated to be 25.2 n Gy.h1 this value has been corrected for build-up, windows and door factors. (Author)

  15. 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

    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...... static and dynamic moisture storage data and the more pronounced was the corresponding dynamic hysteresis. The paper thus provides clear experimental evidence on dynamic effects in the water content – water potential relation of building materials. By that, data published by previous authors as Topp et...

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

    International Nuclear Information System (INIS)

    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

  17. 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.

  18. 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. PMID:27016882

  19. 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.

  20. 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. PMID:10347000

  1. Measurement of radium concentration and radon exhalation rate in building material samples

    International Nuclear Information System (INIS)

    Building materials are the main source of radon in the dwellings. Therefore measurement of radon exhalation rate from these materials will help in the prediction of existence of dwelling with potential radon risk. Radon exhalation rate from building materials varies with type and origin. Emanation of radon is associated with the presence of radium and its ultimate precursor uranium in the ground. Solid state nuclear track detectors (LR-115 TYPE-II) are used to determine radon exhalation rate in building material samples collected from the different locations of Himachal Pradesh. SSNTD mainly detects the alpha particles having energy ranging from 1.7 to 4.8 MeV. For this purpose, building materials are collected in plastic can containing LR-115 TYPE-II solid state nuclear track detectors which are very sensitive for alpha particles. The samples are granite, marble and sandstone. There is a large variation in values of radon exhalation rate which may be due to the difference in radium content. The exhalation rate for the measured samples varies from 40.72 mBqkg-1h-1(sandstone) to 81.40 mBqkg-1h-1(granite). From the results, it is clear that granite sample shows higher radon exhalation rate than that of marble and sandstone samples. The emanation coefficient and effective alpha dose equivalent is also calculated for the health risk assessment. (author)

  2. Energy and economic analysis of a building enclosure outfitted with a phase change material board (PCMB)

    International Nuclear Information System (INIS)

    Highlights: • Phase change material boards (PCMBs) were simulated in building enclosures. • Energy and economic savings for these buildings were estimated. • The buildings were located in five cities with different climatic conditions. • The energy savings ratio was 100% when a cold energy source was used. • A mean electricity savings ratio of 13.1% was obtained. - Abstract: This paper presents energy and economic analyses related to the application of phase change materials boards (PCMBs) in building enclosures during the cooling season. A heat transfer model was developed, which was implemented via a computer program. Simulations were carried out using weather data files from five cities located in five different climate regions in China. Energy savings from using a natural cold source (e.g., outdoor air) and electricity savings from a reduction in electricity by air conditioning systems were evaluated. The energy savings ratio (ESR) and simple payback period (SPP) were used to assess the application of PCMBs in building enclosures. The selection of optimum phase transition temperatures for the PCMs for the various climates was made using indoor and outdoor air temperatures, as well as SPP. For space cooling purposes, it was suggested that phase transition temperatures should be at least 3 °C higher than the mean outdoor air temperature. Simple payback period suggested the possibility of the cost effective use of PCMBs in occupied buildings for moderate temperature climates

  3. In vivo degradation in modern orthopaedic UHMWPE bearings and structural characterization of a novel alternative UHMWPE material

    Science.gov (United States)

    Reinitz, Steven D.

    Ultra-high molecular weight polyethylene (UHMWPE) remains the most common bearing material for total joint arthroplasty. Advances in radiation cross-linking and other post-consolidation treatments have led to a rapid differentiation of polyethylene products on the market, with more than twenty unique materials currently being sold by the five largest orthopaedic manufacturers alone. Through oxidation, cross-link density, and free radical measurements, this work demonstrates for the first time that in vivo material degradation is occurring in cross-linked UHMWPE materials. Based on the rate of the reaction in certain materials, it is concluded that oxidative degradation may compromise the mechanical properties of the bearings in as few as ten years, potentially leading to early clinical failure of the devices. Using the knowledge gained from this work as well as previously published observations about UHMWPE oxidation, a two-mechanism model of oxidation is proposed that offers an explanation for the observed in vivo changes. From this model it is concluded that oxidative degradation is in part the result of in vivo chemical species. The two-mechanism model of oxidation suggests that different processing techniques for UHMWPE may reduce the risk of oxidative degradation. It is concluded that by avoiding any radiation cross-linking step, Equal Channel Angular Processing (ECAP) can produce UHMWPE materials with a reduced risk for in vivo oxidation while at the same time offering superior mechanical properties compared to commercially available UHMWPE materials, as well as similar wear behavior. Using dynamic mechanical analysis, the entanglement density in ECAP materials is quantified, and is related back to the ECAP processing parameters. The relationship between entanglement density and resultant material properties is established. The results will allow informed processing parameter selection for producing optimized materials for orthopaedics and other applications.

  4. Survey of degradation modes of candidate materials for high-level radioactive-waste disposal containers

    International Nuclear Information System (INIS)

    Three copper-based alloys --- CDA 102 (OFHC copper), CDA 613 (aluminum bronze), and CDA 715 (Cu-30Ni) --- are being considered as possible materials for the fabrication of high-level radioactive-waste disposal containers. Waste will include fuel assemblies from reactors as well as borosilicate glass forms, and will be sent to the prospective repository at Yucca Mountain, Nevada, for emplacement. The three copper-based alloys discussed here are being considered in addition to the iron- to nickel-based austenitic materials discussed in Volume 3. The decay of radionuclides will result in substantial heat generation and in fluxes of gamma radiation. In this environment, container materials may degrade by atmospheric oxidation, uniform aqueous phase corrosion, pitting, crevice corrosion, transgranular stress corrosion cracking (TGSCC) in tarnishing environments, or intergranular stress corrosion cracking (IGSCC) in nontarnishing environments. This report is a critical survey of available data on the stress corrosion cracking (SCC) of the three copper-based alloys. The requisite conditions for TGSCC and IGSCC include combinations of stress, oxygen, ammonia or nitrite, and water. Note that nitrite is generated by gamma radiolysis of moisture films in air but that ammonia is not. TGSCC has been observed in CDA 102 and CDA 613 exposed to moist ammonia-containing environments whereas SCC has not been documented for CDA 715 under similar conditions. SCC is also promoted in copper by nitrite ions. Furthermore, phosphorus-deoxidized copper is unusually susceptible to embrittlement in such environments. The presence of tin in CDA 613 prevents IGSCC. It is believed that tin segregates to grain boundaries, where it oxidizes very slowly, thereby inhibiting the oxidation of aluminum. 117 refs., 27 figs., 9 tabs

  5. 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.

  6. 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

  7. Aggregate material formulated with MSWI bottom ash and APC fly ash for use as secondary building material

    International Nuclear Information System (INIS)

    Highlights: ► A concrete formulation was optimized using Bottom Ash and APC ash. ► 10% of APC ash achieves good compromise between economic and performance aspects. ► The crushed concrete was evaluated as secondary building granular material. ► The environmental behavior allows its use as secondary material. ► The abrasion resistance is not good enough for its use as a road sub-base material. - Abstract: The main goal of this paper is to obtain a granular material formulated with Municipal Solid Waste Incineration (MSWI) bottom ash (BA) and air pollution control (APC) fly ash to be used as secondary building material. Previously, an optimum concrete mixture using both MSWI residues as aggregates was formulated. A compromise between the environmental behavior whilst maximizing the reuse of APC fly ash was considered and assessed. Unconfined compressive strength and abrasion resistance values were measured in order to evaluate the mechanical properties. From these results, the granular mixture was not suited for certain applications owing to the high BA/APC fly ash content and low cement percentages used to reduce the costs of the final product. Nevertheless, the leaching test performed showed that the concentrations of all heavy metals were below the limits established by the current Catalan legislation for their reutilization. Therefore, the material studied might be mainly used in embankments, where high mechanical properties are not needed and environmental safety is assured

  8. 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

  9. Influence of Building Material Solution of Structures to Effectiveness of Real Estate Development

    Science.gov (United States)

    Somorová, Viera

    2015-11-01

    Real estate development is in its essence the development process characterized by a considerable dynamics. The purpose of the development process is the creation of buildings which can be either rented by future unknown users or sold in the real estate market. A first part of the paper is dedicated to the analysis of the parameters of buildings solutions considering the future operating costs in a phase of designing. Material solution of external structures is a main factor not only in determining the future operating costs but also in achieving the subsequent economic effectiveness of the real estate development. To determine the relationship between economic efficiency criteria and determine the optimal material variant of building constructions for the specific example is the aim of the second part of paper.

  10. A quantitative approach to the assessment of the environmental impact of building materials

    Energy Technology Data Exchange (ETDEWEB)

    Harris, D.J. [Heriot-Watt Univ., Dept. of Building Engineering and Surveying, Edinburgh (United Kingdom)

    1999-07-01

    The materials from which a building is constructed make a significant contribution to its overall impact on the environment. This impact is felt in a number of ways; locally, through the effects of activities such as quarrying; globally, as a result of carbon dioxide released by using energy used to manufacture the materials; and internally, in the effects of health of the occupants of the building. Some of these effects are easier to measure than others, and comparisons between the seriousness of the different effects are difficult to make. It therefore seems unreasonable to attempt to advise a single figure of merit for the overall environmental impact of a building: what is needed is a profile which gathers together a range of indicators, but allows them to remain separate. This article describes the development of such an environmental profile which can be used as a design aid, and illustrates its use with a case study of a typical British house. (Author)

  11. Development and Application of High-Cr Ferritic Stainless Steels as Building Exterior Materials

    International Nuclear Information System (INIS)

    Stainless Steels have been widely used as a building exterior materials in Asian countries for the last decade. It is required for the materials in this field to have an aesthetic appearance,a relatively high strength, and an excellent corrosion resistance. Other metallic materials such as copper, aluminum, and carbon steels have been also used as the exterior materials. Considering the cost of maintenance, stainless steel, having the outstanding corrosion resistance, is replacing other materials in the several parts in the building exteriors. Ferritic stainless steel has been applied as the roofing materials because its thermal expansion is much smaller than that of austenitic stainless steel. Therefore, it is suitable for the large-scale construction such as airport terminal, convention center, and football stadium. To improve the corrosion resistance of the ferritic stainless steels, the modification of alloy composition has been studied to develop new grade materials and the progress in the surface technology has been introduced. Corrosion properties, of these materials were evaluated in the laboratory and in the field for longer than two years. High-Cr ferritic stainless steel showed excellent corrosion resistance to the atmospheric environments. In the region close to the sea, the corrosion resistance of high-Cr ferritic stainless steel was much superior to that of other materials, which may prove this steel to be the appropriate materials for the construction around seashore. In some of the large constructions around seashore in South Korea, high-Cr ferritic stainless steels have been used as the building exterior materials for six years

  12. Dose and radon measurements inside houses containing ash as building material

    International Nuclear Information System (INIS)

    Radon concentration and external dose have been measured in dwellings that contain by-products of coal burning for building materials. The concentrations of 40K, 232Th, 238U and 226Ra have been determined in the materials. The date are analyzed according to indices frequently used for decision of utilizing the by-products. The observed daily fluctuation of the radon concentration in dwellings might exceed a factor of 5. (author)

  13. Degradation of dental ZrO2-based materials after hydrothermal fatigue. Part I: XRD, XRF, and FESEM analyses.

    Science.gov (United States)

    Perdigão, Jorge; Pinto, Ana M; Monteiro, Regina C C; Braz Fernandes, Francisco M; Laranjeira, Pedro; Veiga, João P

    2012-01-01

    The aim was to investigate the effect of simulated low-temperature degradation (s-LTD) and hydrothermal fatigue on the degradation of three ZrO(2)-based dental materials. Lava, IPS, and NanoZr discs were randomly assigned to (1) Control-Storage in distilled water at 37°C; (2) Aging at 134°C for 5 h (s-LTD); (3) Thermocycling in saliva for 30,000 cycles (TF). XRD revealed that ZrO(2) m phase was identified in all groups but TF increased the m phase only for Lava. Under the FESEM, Lava showed no alterations under s-LTD, but displayed corrosion areas up to 60 µm wide after TF. We conclude that TF accelerated the degradation of Lava through an increase in the m phase and grain pull-out from the material surface. PMID:22447060

  14. Mechanical degradation under hydrogen of yttrium doped barium zirconate electrolyte material prepared with NiO additive

    Science.gov (United States)

    Ciria, D.; Ben Hassine, M.; Jiménez-Melendo, M.; Iakovleva, A.; Haghi-Ashtiani, P.; Aubin, V.; Dezanneau, G.

    2016-07-01

    Recently, a novel process was presented to fabricate dense yttrium-doped barium zirconate electrolytes with high proton conductivity. This process was based on the use of a NiO additive during reactive sintering. We show here that materials made from this process present a fast degradation of mechanical properties when put in hydrogen-rich conditions, while material made from conventional sintering without NiO aid remains intact in the same conditions. The fast degradation of samples made from reactive sintering, leading to sample failure under highly compressive conditions, is due to the reduction of NiO nanoparticles at grain boundaries as shown from structural and chemical analyses using Transmission Electron Microscopy. By the present study, we alert about the potential risk of cell failure due to this mechanical degradation.

  15. Fate and transport of radiocesium, radiostrontium and radiocobalt on urban building materials

    International Nuclear Information System (INIS)

    Kinetics of 137Cs, 60Co and 85Sr sorption on powdered building materials in aqueous suspensions at 20 °C for interaction times of 1, 7, 14 and 28 days were studied. The 137Cs distribution coefficient (Kd) values for all building materials except limestone practically did not change during 28 days of sorption. The Kd (85Sr) was several orders of magnitude lower than for 60Co. The highest values were observed for asphalt and granite. An effective method to study the radionuclide distribution in depth of building materials using layer-by-layer sanding was developed. Using the developed method, the 137Cs, 60Co and 85Sr distribution with depth of selected building materials at different air humidity, time and temperature was studied. Relative humidity (RH) was found to influence significantly the 85Sr depth distribution in the case of granite (unlike 137Cs and 60Co). While 85Sr penetrated to 0.5 mm in depth of granite at RH 30%, at RH 87% the depth of 85Sr penetration to granite reached up to 7 mm

  16. A preliminary intercomparison of gamma-ray spectroscopy on building materials

    NARCIS (Netherlands)

    Anagnostakis, M.J.; Bolzan, C.; De Felice, P.; Fazio, A.; Grisanti, G.; Risica, S.; Turtiainen, T.; van der Graaf, E.R.

    2004-01-01

    A preliminary intercomparison on gamma-ray spectrometry determination of natural radionuclides in building materials was carried out in 1999-2002. Samples measured were fly ash, sand and tuff. Laboratories used different experimental equipment and procedures. Corrections for blank, spectral interfer

  17. Radiological and hazardous material characterization report for the south portion of the 313 Building

    International Nuclear Information System (INIS)

    The objective of the characterization was to determine the extent of radiological contamination and presence of hazardous materials, to allow the preparation of an accurate cost estimate, and to plan for pre-demolition cleanup work to support building isolation. The scope of services for the project included the following tasks: Records Review and Interviews; Site Reconnaissance; Radiological Survey; and Sampling and Analysis

  18. 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. 779.336 Section 779.336 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR STATEMENTS OF GENERAL POLICY OR INTERPRETATION NOT DIRECTLY RELATED TO REGULATIONS THE FAIR LABOR STANDARDS ACT AS APPLIED...

  19. 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…

  20. 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…

  1. RESRAD-BUILD: A computer model for analyzing the radiological doses resulting from the remediation and occupancy of buildings contaminated with radioactive material

    Energy Technology Data Exchange (ETDEWEB)

    Yu, C.; LePoire, D.J.; Jones, L.G. [and others

    1994-11-01

    The RESRAD-BUILD computer code is a pathway analysis model designed to evaluate the potential radiological dose incurred by an individual who works or lives in a building contaminated with radioactive material. The transport of radioactive material inside the building from one compartment to another is calculated with an indoor air quality model. The air quality model considers the transport of radioactive dust particulates and radon progeny due to air exchange, deposition and resuspension, and radioactive decay and ingrowth. A single run of the RESRAD-BUILD code can model a building with up to: three compartments, 10 distinct source geometries, and 10 receptor locations. A shielding material can be specified between each source-receptor pair for external gamma dose calculations. Six exposure pathways are considered in the RESRAD-BUILD code: (1) external exposure directly from the source; (2) external exposure to materials deposited on the floor; (3) external exposure due to air submersion; (4) inhalation of airborne radioactive particulates; (5) inhalation of aerosol indoor radon progeny; and (6) inadvertent ingestion of radioactive material, either directly from the sources or from materials deposited on the surfaces of the building compartments. 4 refs., 23 figs., 4 tabs.

  2. RESRAD-BUILD: A computer model for analyzing the radiological doses resulting from the remediation and occupancy of buildings contaminated with radioactive material

    International Nuclear Information System (INIS)

    The RESRAD-BUILD computer code is a pathway analysis model designed to evaluate the potential radiological dose incurred by an individual who works or lives in a building contaminated with radioactive material. The transport of radioactive material inside the building from one compartment to another is calculated with an indoor air quality model. The air quality model considers the transport of radioactive dust particulates and radon progeny due to air exchange, deposition and resuspension, and radioactive decay and ingrowth. A single run of the RESRAD-BUILD code can model a building with up to: three compartments, 10 distinct source geometries, and 10 receptor locations. A shielding material can be specified between each source-receptor pair for external gamma dose calculations. Six exposure pathways are considered in the RESRAD-BUILD code: (1) external exposure directly from the source; (2) external exposure to materials deposited on the floor; (3) external exposure due to air submersion; (4) inhalation of airborne radioactive particulates; (5) inhalation of aerosol indoor radon progeny; and (6) inadvertent ingestion of radioactive material, either directly from the sources or from materials deposited on the surfaces of the building compartments

  3. Radon exhalation rate from coal ashes and building materials in Italy

    International Nuclear Information System (INIS)

    The Italian National Electricity Board, in cooperation with Centro Informazioni Stubi Esperienze (CISE) has a program to assess the hazards connected with using fly ash in civil applications as partial substitutes for cement and other building materials. We investigated the natural radioactivity levels of more than 200 building materials. The survey involved materials available in Italy, categorized by geographical location and type of production. We also examined approximately 100 samples of fly ash from United States and South African coal, obtained from Italian power plants. Exhalation rates from about 40 powdered materials were determined by continuously measuring radon concentration growth in closed containers. Measurements were also performed on whole bricks, slabs, and titles. Details about the high-sensitivity measuring devices are presented. The influence of fly ash on exhalation rates was investigated by accurately measuring radon emanation from slabs with various ash/cement ratios and with slabs of inert materials having various radium concentrations. We will discuss results of forecasting indoor radon concentrations under different ventilation conditions. Two identical test rooms are being built, one with conventional and one with fly-ash building materials, to compare theoretical calculations with experimental data. Specifications for instruments to control and to measure the most important parameters are also discussed

  4. Natural radionuclides in ceramic building materials available in Cuddalore district, Tamil Nadu, India

    International Nuclear Information System (INIS)

    The activity concentrations of radium, thorium and potassium can vary from material to material and they should be measured as the radiation is hazardous for human health. Thus, studies have been planned to obtain the radioactivity of ceramic building materials used in Cuddalore District, Tamilnadu, India. The radioactivity of some ceramic materials used in this region has been measured using a gamma-ray spectrometry, which contains an NaI(Tl) detector connected to multichannel analyzer. The specific activities of 226Ra, 232Th and 40K, from the selected ceramic building materials, were in the range of 9.89-30.75, 24.68-70.4, 117.19-415.83 Bq kg-1, respectively. The radium equivalent activity, absorbed gamma dose rate (D) and annual effective dose rate associated with the natural radionuclides are calculated to assess the radiation hazards of the natural radioactivity in the ceramic building materials. It was found that none of the results exceeds the recommended limit value. (authors)

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

    International Nuclear Information System (INIS)

    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: ► Up to thirteen extraction methods were evaluated with three building materials.

  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. An application of luminescence dating to building archaeology: The study of ceramic building materials in early medieval churches in south-eastern England and north-western France

    OpenAIRE

    Blain, Sophie

    2010-01-01

    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 ...

  8. Annual mean effective dose of Slovak population due to natural radioactivity of building materials

    International Nuclear Information System (INIS)

    Natural radiation is the main source of exposure to humans. The basic raw materials, generally used in the construction industry, contain natural radionuclides which reflects their natural origin and the geological conditions at the site of production. In the last time, most building materials are manufactured from secondary raw materials with higher concentration of natural radionuclides. The estimation of the 226 Ra content as well as the 232 Th and 40 K concentration in building materials and products is essential for the evaluation of the external x-ray contribution to the exposure. The building materials with high value of 226 Ra coupled with pronounced porosity of the final products make them potential indoor Rn sources. It means that external exposure and part of inhalation dose from radon and its progeny inside of building is caused to the radiation from the primordial radionuclides pres ent in building materials and products and can increase the indoor natural radiation exposure. For keeping the population exposure as low as reasonably achievable is in the Slovak legislation the radioactive content of primordial radionuclides in building materials and products regulated and the maximum of specific activity is 370 Bq.kg-1 of radium equivalent activity and 120 Bq.kg-1 of 226 Ra. The Health ministry and Slovak metrological institute nominated the department of Radiation Hygiene of Slovak medical university to investigate regularly the content of natural radionuclides and also the radon emanation in samples of raw and secondary building materials and products used in Slovak building industry. In the framework of the screening of building materials and products there were analyzed over 3 000 samples. The natural radionuclides are assessed through their progeny photo peaks. The specific activity of nuclides is determined as weighted average of their photo peaks. The obtained results are corrected to the background distribution and to the self absorption in the

  9. Fundamental degradation mechanisms of layered oxide Li-ion battery cathode materials: Methodology, insights and novel approaches

    International Nuclear Information System (INIS)

    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 LiMO2 (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

  10. Novel Fe-Pd/SiO2 catalytic materials for degradation of chlorinated organic compounds in water

    Science.gov (United States)

    Novel reactive materials for catalytic degradation of chlorinated organic compounds in water at ambient conditions have been prepared on the basis of silica-supported Pd-Fe nanoparticles. Nanoscale Fe-Pd particles were synthesized inside porous silica supports using (NH4

  11. 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)

  12. Radiation damage of graphite: degradation of material parameters and defect structures

    International Nuclear Information System (INIS)

    On the basis of our previous work, we have discussed the relation between damage structure and the degradation of the material parameters of neutron-irradiated graphites.The defects produced in a basal plane and/or in between the basal planes (in-plane or two-dimensional defects), which are appreciable in the early stage of irradiation, seem to play a critically important role both in the reduction in the thermal conductivity and increase in the hydrogen retention. They also cause a dimensional change through increase in lattice spacing between the basal planes of graphite. Although the in-plane defects are rather easily annealed out, there seems to be no way to avoid their production under neutron irradiation, particularly at low temperatures. After heavy irradiation, the defects grow into three-dimensional clusters, probably accompanying some sp2-to-sp3 transition. They play an important role in volume expansion and result in complete loss of the layered structure of graphite (amorphization), which is very difficult to anneal. Considering the annealing behaviors of the thermal conductivity, lattice constant and electrical resistivity, we propose a new model based on the sp2-to-sp3 transition that can explain the observed effect for both damage and annealing processes without any contradiction. (orig.)

  13. Structure, physicochemical properties and in vitro fermentation of enzymatically degraded cell wall materials from apples.

    Science.gov (United States)

    Förster, S; Dongowski, G; Kunzek, H

    2002-06-01

    Cell wall materials (CWM) prepared from apple parenchyma tissue by treatment with commercial enzymes for maceration, mash fermentation and liquefaction were characterised with regard to their composition and structure as well as their physicochemical and physiological properties. Increasing enzymatic degradation of the CWM resulted in growing loss of the pectin matrix, decreasing porosity as well as increasing particle aggregation. Due to these structural alterations the water binding, the viscoelastic properties of the CWM-water-suspensions and the in vitro fermentation, forming short chain fatty acids, were reduced. The investigations showed that interrelations exist between enzymatic treatment and changes of (i) structure and state of matrices (evaluated by means of thermal analysis), (ii) physicochemical properties and (iii) physiological properties. So the application of liquefying enzymes can lead to a complete removal of the pectin matrix, causing an essentially improved thermal stability of the CWM preparation, but strongly reduced water binding and reduced structure-forming properties into the CWM-water-suspensions. The formation of short-chain fatty acids during in vitro fermentation of the CWM preparations by fresh human faeces flora depended on the portion and the state of the pectin matrix and the cellulose network, respectively. PMID:12108214

  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. 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.

  16. Irradiation chamber for gamma degradation studies in tokamak optical transmission materials

    International Nuclear Information System (INIS)

    Ceramic materials are anticipated to play very important roles in developing nuclear fusion reactors, where they will be used under heavy irradiation environments (neutrons, gamma-rays, protons, helium and other ions) for substantial periods. Extensive studies have been carried out for several decades on fundamental aspects of the radiation effects upon the ceramic. Indeed we need to understand the effects induced not only of irradiation by neutrons and alpha particles but also by gamma rays and protons. We intend to start a general programme on gamma and proton induced degradation in optical transmission materials, including windows and optical fibres. As a first step, we shall concentrate on assessing the suitability of SiO2 based materials for both diagnostic and handling applications. We designed a gamma irradiation chamber, acting underwater, allowing various temperatures (20 deg. C -- 300 deg. C) on the sample; this involves finding adequate solutions for dosimetry, heating system and UV absorption and radioluminescence apparatuses (including their information transmission systems) acting in a high gamma ray field intensity in the water pool of the Co-60 irradiator. This chamber has the following characteristics: - adequate oven for 20 deg. C -- 300 deg. C on ceramic samples, remotely handled; - remote sensing thermocouples; - provided is the application of an electric field on the sample during heating; - water-tight and resistant to a 3 m height water column; corrosion processes avoided (copper O-rings used); - standardized air- water electrical connections for submersion action; adequate electrical protection - availability for insertion of in-situ luminescence studies equipment; - availability for remote handling in experimental operations; modifications implied by use of long electrical cables established - evaluation of gamma irradiation induced modifications in chamber's components (especially cables - polymers, etc); finding of resistant materials

  17. 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.

  18. Survey of degradation modes of candidate materials for high-level radioactive-waste disposal containers

    International Nuclear Information System (INIS)

    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. Bio-susceptibility of materials and thermal insulation systems used for historical buildings

    Science.gov (United States)

    Sterflinger, Katja; Ettenauer, Joerg; Pinar, Guadalupe

    2013-04-01

    In historical buildings of Northern countries high levels of energy are necessary to reach comfortable temperatures especially during the cold season. For this reason historical buildings are now also included in country specific regulations and ordinances to enhance the "energy - efficiency". Since an exterior insulation - as it is commonly used for modern architecture - is incompatible with monument protection, several indoor insulation systems based on historical and ecological materials, are on the market that should improve the thermic performance of a historical building. However, using organic materials as cellulose, loam, weed or wood, bears the risk of fungal growth and thus may lead to health problems in indoor environments. For this reason 5 different ecological indoor insulations systems were tested for their bio-susceptibility against various fungi both under natural conditions - after 2 years of installation in an historical building - and under laboratory conditions with high levels of relative humidity. Fungal growth was evaluated by classical isolation and cultivation as well as by molecular methods. The materials turned out to have a quite different susceptibility towards fungal contamination. Whereas insulations made of bloated Perlite (plaster and board) did not show any fungal growth after 2 years of exposition, the historical insulation made of loam and weed had high cell counts of various fungi. In laboratory experiments wooden softboard represented the best environment for fungal growth. As a result from this study, plaster and board made of bloated Perlite are presented as being the most appropriate materials for thermal insulation at least from the microbiological and hygienic point of view. For future investigations and for the monitoring of fungi in insulation and other building materials we suggest a molecular biology approach with a common protocol for quantitative DNA-extraction and amplification.

  20. Radon exhalation rate from the building materials of Tiruchirappalli district (Tamil Nadu State, India)

    International Nuclear Information System (INIS)

    Tiruchirappalli district has enriched resources of building materials such as stone, granite, sand, brick, cement, etc., which are also supplied to the neighbouring districts. Since radon is considered as one of the causative factors for human lung diseases, the measurement of the radon level in these building materials is imperative for the assessment. The samples of building materials were collected from their original sources spread over Tiruchirappalli district. The sealed can technique with solid state nuclear track detector (SSNTD) was employed for the measurement of radon exhalation. The activity concentrations of radon in sedimentary rocks analyzed ranged from 13.2 Bq/m3 to 218.0 Bq/m3 with the geometric mean activity of 46.3 Bq/m3. However, radon concentrations in igneous rocks are distinctly higher than those of sedimentary rocks and ranged from 95.6 Bq/m3 to 1140 Bq/m3 with the geometric mean activity concentration of 392.6 Bq/m3. The radon exhalation from sand, brick, and cement were found to be non-uniform (sand: 119.8-656 Bq/m3, brick: 31-558 Bq/m3, cement: 172-300 Bq/m3). The activity concentration of radon in these building materials follow a descending order: Granite > sand > cement > brick > sand stone. The mass and surface exhalation (EM and EA) rates also follow the same order. The study concludes that since the radon exhalation from the building materials was less than the International Commission on Radiological Protection limit of 1500 Bq/m3, they do not pose any radiological risk. (author)

  1. Cometabolic Degradation of Trichloroethene by Rhodococcus sp. Strain L4 Immobilized on Plant Materials Rich in Essential Oils▿ †

    OpenAIRE

    Suttinun, Oramas; Müller, Rudolf; Luepromchai, Ekawan

    2010-01-01

    The cometabolic degradation of trichloroethene (TCE) by Rhodococcus sp. L4 was limited by the loss of enzyme activity during TCE transformation. This problem was overcome by repeated addition of inducing substrates, such as cumene, limonene, or cumin aldehyde, to the cells. Alternatively, Rhodococcus sp. L4 was immobilized on plant materials which contain those inducers in their essential oils. Cumin seeds were the most suitable immobilizing material, and the immobilized cells tolerated up to...

  2. 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

  3. Some Materials Degradation Issues in the U.S. High-Level Nuclear Waste Repository Study (The Yucca Mountain Project)

    International Nuclear Information System (INIS)

    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

  4. 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.

  5. 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).

  6. Study of building materials impregnation processes by quasi-real-time neutron radiography

    Energy Technology Data Exchange (ETDEWEB)

    Nemec, T. [Jozef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia); Rant, J. [Jozef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia); Apih, V. [National Building and Civil Engineering Institute, Ljubljana (Slovenia); Glumac, B. [Jozef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia)

    1999-11-03

    Neutron radiography (NR) is a useful non-destructive method for determination of hydrogen content in various building and technical materials. Monitoring of transport processes of moisture and hydrogenous liquids in porous building materials is enabled by fast, quasi-real-time NR methods based on novel imaging plate neutron detectors (IP-NDs). Hydrogen content in the samples is determined by quantitative analysis of measured profiles of neutron attenuation in the samples. Detailed description of quantitative NR method is presented by the authors in another accompanying contribution at this conference. Deterioration of building materials is originated by different processes that all require presence of water therefore it is essential to limit or prevent the transport of water through the porous material. In this presentation, results of a study of clay brick impregnation by silicone based hydrophobic agents will be presented. Quantitative results obtained by NR imaging successfully explained the processes that occur during the impregnation of porous materials. Efficiency of hydrophobic treatment was quantitatively evaluated.

  7. 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.

  8. Natural Radioactivity and 222Rn Exhalation Rate from Brazilian Phosphogypsum Building Materials

    International Nuclear Information System (INIS)

    Phosphogypsum is classified as a NORM residue and one of the main environmental concerns of its use is the radon exhalation from this material. The aim of this study is to determine the activity concentration of natural radionuclides, radium equivalent activities, external and internal hazard index and the radon exhalation rate from bricks and plates made of phosphogypsum. The activity concentration and radon exhalation rate were in accordance with literature values. The results of radium equivalent, external and internal hazard index showed that plates and bricks from Ultrafertil and Fosfertil presented values above the recommended limits; indicating the necessity of using more realistic models for the safe application of phosphogypsum as building materials. The results of this study can contribute for the establishment of guidelines by the Brazilian regulatory agency, for the safe use of phosphogypsum as building material. (author)

  9. Radiation dose contribution from coal-slag from the Ajka region used as structural building material

    Energy Technology Data Exchange (ETDEWEB)

    Somali, J.; Kanyar, B.; Lendvai, Z.; Nemeth, C.; Bodnar, R. [Veszpremi Egyetem, Veszprem (Hungary). Radiokemia Tanszek

    1997-10-01

    A significant dose contribution on the population could be derived from coal slags used as material in buildings. Extremely high natural activities are measured in the coal slag from the region of Ajka, Hungary. The main conclusions based on the results of the monitoring of the gamma-dose rate and the radon concentration in the air in nearly 240 houses are as follows: (1) for individuals, such as children, spending a long time at home (19.2 h/day) the external annual dose is 1.7-4.5 mSv; (2) in the majority of houses with local slag the estimated annual average value of indoor-radon concentration was above 400 Bq/m{sup 3}, and in several cases there were buildings with values over 1200 Bq/m{sup 3}. In these cases the internal annual dose of the dwellers can be estimated between 6-20 mSv; (3) due to the elevated gamma-exposure and the radon concentration in the dwellings the total annual dose was estimated as 8-24 mSv, more than 5-10 times the world average value; and (4) some of the houses were built after the 1960s, when the use of slags from the region of Ajka as building material was already banned by the authorities. In addition to the regulations an effective radiological control should be introduced and a practice for testing the use of slag as building material.

  10. Characterization of historic mortars and earthen building materials in Abu Dhabi Emirate, UAE

    International Nuclear Information System (INIS)

    The Abu Dhabi Authority for Culture and Heritage (ADACH) is responsible for the conservation and management of historic buildings and archaeological sites in the Emirate. Laboratory analysis has been critical for understanding the composition of historic materials and establishing appropriate conservation treatments across a wide variety of building types, ranging from Iron Age earthen archaeological sites to late-Islamic stone buildings. Analysis was carried out on historic sites in Al Ain, Delma Island and Liwa Oasis using techniques such as micro-x-ray fluorescence (MXRF), scanning electron microscopy/energy dispersive x-ray spectroscopy (SEM-EDX), polarized light microscopy (PLM), and x-ray diffraction (XRD). Testing was conducted through consultant laboratories and in collaboration with local universities. The initial aim of the analysis was to understand historic earthen materials and to confirm the suitability of locally sourced clays for the production of mud bricks and plasters. Another important goal was to characterize materials used in historic stone buildings in order to develop repair mortars, renders and grouts.

  11. Effective density and mass attenuation coefficient for building material in Brazil

    International Nuclear Information System (INIS)

    This paper presents values for density and mass attenuation coefficient of building materials commonly used in Brazil. Transmission measurements were performed to provide input information for simulations with MCNP4B code. The structure for the clay bricks was simulated as a mix of all material layers and an effective density determined. The mass attenuation coefficients were determined for the 50-3000 keV gamma-ray energy range. A comparison with results for similar materials found in the literature showed good agreement

  12. Effective density and mass attenuation coefficient for building material in Brazil.

    Science.gov (United States)

    Salinas, I C P; Conti, C C; Lopes, R T

    2006-01-01

    This paper presents values for density and mass attenuation coefficient of building materials commonly used in Brazil. Transmission measurements were performed to provide input information for simulations with MCNP4B code. The structure for the clay bricks was simulated as a mix of all material layers and an effective density determined. The mass attenuation coefficients were determined for the 50-3,000 keV gamma-ray energy range. A comparison with results for similar materials found in the literature showed good agreement. PMID:16257357

  13. 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.

  14. The model constructions of price forming of building materials manufacture in Bashkortostan

    OpenAIRE

    Khamid Gizatullin; Liliya Guzairova

    2007-01-01

    In this work attempt has been done analyze the influence of the environmental factors, as outward, as inside to choice of the strategy and the pricing of the industry of the building materials of Bashkortostan. This article examines the competitive surroundings of enterprises and branches in a aspect of the regional market of the building industry’s production. The evaluation of the compatibility is given of the price and competitive strategy. As a result of the research and pricing majorit...

  15. Solar driven nitrous acid formation on building material surfaces containing titanium dioxide: A concern for air quality in urban areas?

    Science.gov (United States)

    Langridge, Justin M.; Gustafsson, R. Joel; Griffiths, Paul T.; Cox, R. Anthony; Lambert, Richard M.; Jones, Roderic L.

    The photoenhanced uptake of nitrogen dioxide (NO 2) to the surface of commercially available self-cleaning window glass has been studied under controlled laboratory conditions. This material is one of an array of modern building products which incorporate titanium dioxide (TiO 2) nanoparticles and are finding increasing use in populated urban areas. Amongst the principal drivers for the use of these materials is that they are thought to facilitate the irreversible removal of pollutants such as NO 2 and organic molecules from the atmosphere and thus act to remediate air quality. While it appears that TiO 2 materials do indeed remove organic molecules from built environments, in this study we show that the photoenhanced uptake of NO 2 to one example material, self-cleaning window glass, is in fact accompanied by the substantial formation (50-70%) of gaseous nitrous acid (HONO). This finding has direct and serious implications for the use of these materials in urban areas. Not only is HONO a harmful respiratory irritant, it is also readily photolysed by solar radiation leading to the formation of hydroxyl radicals (OH) together with the re-release of NO x as NO. The net effect of subsequent OH initiated chemistry can then be the further degradation of air quality through the formation of secondary pollutants such as ozone and VOC oxidation products. In summary, we suggest that a scientifically conceived technical strategy for air quality remediation based on this technology, while widely perceived as universally beneficial, could in fact have effects precisely opposite to those intended.

  16. Characterization of cement-based ancient building materials in support of repository seal materials studies

    International Nuclear Information System (INIS)

    Ancient mortars and plasters collected from Greek and Cypriot structures dating to about 5500 BC have been investigated because of their remarkable durability. The characteristics and performance of these and other ancient cementitious materials have been considered in the light of providing information on longevity of concrete materials for sealing nuclear waste geological repositories. The matrices of these composite materials have been characterized and classified into four categories: (1) gypsum cements; (2) hydraulic hydrated lime and hydrated-lime cements; (3) hydraulic aluminous and ferruginous hydrated-lime cements (+- siliceous components); and (4) pozzolana/hydrated-lime cements. Most of the materials investigated, including linings of ore-washing basins and cisterns used to hold water, are in categories (2) and (3). The aggregates used included carbonates, sandstones, shales, schists, volcanic and pyroclastic rocks, and ore minerals, many of which represent host rock types of stratigraphic components of a salt repository. Numerous methods were used to characterize the materials chemically, mineralogically, and microstructurally and to elucidate aspects of both the technology that produced them and their response to the environmental exposure throughout their centuries of existence. Their remarkable properties are the result of a combination of chemical (mineralogical) and microstructural factors. Durability was found to be affected by matrix mineralogy, particle size and porosity, and aggregate type, grading, and proportioning, as well as method of placement and exposure conditions. Similar factors govern the potential for durability of modern portland cement-containing materials, which are candidates for repository sealing. 29 references, 29 figures, 6 tables

  17. Estimating the erosion and degradation performance of ceramic and polymeric insulator materials in high current arc environments

    Energy Technology Data Exchange (ETDEWEB)

    Engel, T.G.; Kristiansen, M.; O' Hair, E. (Texas Tech Univ., Lubbock, TX (United States). Dept. of Electrical Engineering); Marx, J.N. (Texas Tech Univ., Lubbock, TX (United States). Dept. of Chemistry and Biochemistry)

    1991-01-01

    This paper reports on the rates of erosion and voltage holdoff degradation which are critical parameters when selecting insulator materials that are used in pulsed power devices such as spark gaps, surface discharge switches, and electromagnetic launchers. This investigation is concerned with modeling the erosion and holdoff degradation performance of various commercially available polymeric and ceramic insulators. The insulators are tested on a surface discharge switch at {approximately}300 kA in atmospheric air. Test diagnostics include the surface voltage holdoff recovery and the eroded mass loss of the insulator and electrode materials used. The ceramic materials which were tested include several types of aluminum and magnesium silicates, several alumina and zirconia composites, and aluminum and silicon nitride. The polymeric insulators include polyvinyl chloride, low and high molecular weight polyethylene, polytetrafluoroethylene, polyamide, acetyl, polyamide-imide, and several types of glass-reinforced epoxies, melamines, and phenolics.

  18. Comparison of different facades for high-rise buildings in hot and cold climates in terms of material usage

    OpenAIRE

    Sief, Salih Ben-Nail Abu

    2014-01-01

    ABSTRACT: Use of “facade” in tall buildings is mainly with materials like glass and aluminum. Other suitable materials are also being used in construction but are not feasible in all climate conditions. Thus, in this study, I am going to present a detailed comparative analysis of glass and aluminum, estimation of their fixing methods, construction and composition of facade materials in architectures‟ aspect. In this era, tall buildings constructed with facade materials having renewable energ...

  19. 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

  20. 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

    2016-12-01

    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. PMID:27314909

  1. Viability of fungal and actinomycetal spores after microwave radiation of building materials.

    Science.gov (United States)

    Górny, Rafał L; Mainelis, Gediminas; Wlazło, Agnieszka; Niesler, Anna; Lis, Danuta O; Marzec, Stanisław; Siwińska, Ewa; Łudzeń-Izbińska, Beata; Harkawy, Aleksander; Kasznia-Kocot, Joanna

    2007-01-01

    The effects of microwave radiation on viability of fungal and actinomycetal spores growing on agar (medium optimal for growth) as well as on wooden panel and drywall (common building construction/finishing materials) were studied. All materials were incubated at high (97-99%) and low (32-33%) relative humidity to mimic "wet" and "dry" environmental conditions. Two microwave power densities (10 and 60 mW/cm2) and three times of exposure (5, 30, and 60 min) were tested to find the most effective parameters of radiation which could be applied to non-invasive reduction or cleaning of building materials from microbial contaminants. Additionally, a control of the surface temperature during the experiments allowed differentiation between thermal and microwave effect of such radiation. The results showed that the viability of studied microorganisms differed depending on their strains, growth conditions, power density of microwave radiation, time of exposure, and varied according to the applied combination of the two latter elements. The effect of radiation resulting in a decrease of spore viability on "wet" wooden panel and drywall was generally observed at 60 min exposure. Shorter exposure times decreased the viability of fungal spores only, while in actinomycetes colonizing the studied building materials, such radiation caused an opposite (supporting growth) effect. PMID:18247470

  2. 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 (

  3. The concentration of natural radionuclides in various types of building materials in Slovakia

    International Nuclear Information System (INIS)

    The concentration of the natural radionuclides in various types of building materials was determined by the gamma spectrometry analysis using 130 cm3 high purity germanium detector and MCA LIVIUS 2000. Radium-226 and thorium-232 was assessed through their progeny photo peaks. The specific activity of both nuclides as weighted average of their photo peaks was determined. Potassium-40 was measured directly via its 1460 keV peak. The radium equivalent activity was calculate from specific activities of radium-226, thorium-232 and potassium-40. All samples were measured in 4pigeometry. The building materials and products were milled and screened with 2-3 mm sieve. After drying the samples were stored in 450 cm3 sealed polyethylene container for 30 days ingrowing period. The results of analysis are corrected to the background distribution and to the self absorption in the volume of the samples. The efficiency calibration is realized using the reference sources distributed by IAEA in Vienna and by the Institute for Radionuclide Production in Prague The measured activity concentrations of the buildings materials are given. There are shown the minimum and maximum values for different investigated materials. (J.K.) 4 tabs., 5 refs

  4. Radon exhalation rate from and natural radioactivity in building materials from HLNRAs of Ramsar, lran

    International Nuclear Information System (INIS)

    Some areas of Ramsar, a city in northern Iran, have among the highest known background radiation levels in the world. Indoor radon has been recognized as one of the health hazards for people who living in this area. The high background radiation in the 'hot' areas of Ramsar is primarily due to the presence of very high amounts of 226Ra and its decay products, which were brought to the earth's surface by hot springs. Area resident have also used the residue of the hot springs as building materials for construction of houses, which are considered as one of the major sources of this gas in indoor environment in these areas. These building materials have been studied for exhalation rate of radon. The radionuclide content of the building materials were determined. A total of 35 samples were analyzed for 226Ra, 232Th and 40K using a low background High Purity Germanium detector (HPGe). The detector was surrounded by a massive lead shield (10 cm) and coupled to a MCA-Series 100. The system was calibrated with respect to energy and efficiency using reference materials (RGU-1), (RGTh-1) and (RGK-1) that were prepared by International Atomic Energy Agency. The mean activity concentrations of radionuclides in most of them are not very high, and these values are near the normal radiation background. The highest values for the activity concentration of different radionuclides and the exposure rate due to natural radionuclides in this study were observed for the building materials that have made from travertine deposits

  5. External exposure doses due to gamma emitting natural radionuclides in some Egyptian building materials

    Energy Technology Data Exchange (ETDEWEB)

    Moharram, B.M. [Engineering Physics and Mathematics Department, Faculty of Engineering, Tanta University, Tanta (Egypt); Suliman, M.N. [Nuclear Engineering Department, Faculty of Engineering, Alexandria University, Alexandria (Egypt); Zahran, N.F. [Center Laboratory for Elemental and Isotopic Analysis, Atomic Energy Authority, Cairo 13759 (Egypt); Shennawy, S.E. [Engineering Physics and Mathematics Department, Faculty of Engineering, Tanta University, Tanta (Egypt); El Sayed, A.R., E-mail: aymanrabie2002@yahoo.co.in [Engineering Physics and Mathematics Department, Faculty of Engineering, Tanta University, Tanta (Egypt)

    2012-01-15

    Using of building materials containing naturally occurring radionuclides as {sup 238}U, {sup 232}Th and {sup 40}K and their progeny results in an external exposures of the housing of such buildings. In the present study, indoor dose rates for typical Egyptian rooms are calculated using the analytical method and activity concentrations of natural radionuclides in some building materials. Uniform chemical composition of the walls, floor and ceiling as well as uniform mass concentrations of the radionuclides in walls, floor and ceiling assumed. Different room models are assumed to discuss variation of indoor dose rates according to variation in room construction. Activity concentrations of {sup 238}U, {sup 232}Th and {sup 40}K content in eight samples representative Clay soil and different building materials used in most recent Egyptian building were measured using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). The specific activity for {sup 238}U, {sup 232}Th and {sup 40}K, from the selected samples, were in the range 14.15-60.64, 2.75-84.66 and 7.35-554.4 Bq kg{sup -1}, respectively. The average indoor absorbed dose rates in air ranged from 0.005 {mu}Gy h{sup -1} to 0.071 {mu}Gy h{sup -1} and the corresponding population-weighted annual effective dose due to external gamma radiation varies from 0.025 to 0.345 mSv. An outdoor dose rate for typical building samples in addition to some radiological hazards has been introduced for comparison. - Highlights: Black-Right-Pointing-Pointer Activity concentrations of {sup 238}U, {sup 232}Th and {sup 40}K content in different building materials measured using HR-ICPMS. Black-Right-Pointing-Pointer Analytical simulation technique has been employed to room models to evaluate indoor specific absorbed dose rates in air. Black-Right-Pointing-Pointer Different room models are assumed to discuss variation of indoor dose rates according to variation in room construction. Black-Right-Pointing-Pointer Comparing the results

  6. Identification and Assessment of Material Models for Age-Related Degradation of Structures and Passive Components in Nuclear Power Plants

    International Nuclear Information System (INIS)

    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. 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.

  8. State of the art review of degradation processes in LMFBR materials. Volume I. Mechanical properties. Volume II. Corrosion behavior. Revision 1

    International Nuclear Information System (INIS)

    A revision to Volume I and Volume II of the LMFBR materials degradation summary is presented. Information is included on NaOH corrosive effects, effects of metal cleaning procedures, and caustic stress corrosion cracking of reactor materials. (JRD)

  9. 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

  10. Effect of using low-polluting building materials and increasing ventilation on perceived indoor air quality

    Energy Technology Data Exchange (ETDEWEB)

    Wargocki, P.; Zuczek, P. (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 potential of improving perceived air quality indoors was quantified when low-polluting materials are used and when building ventilation is increased. This was done by studying the relationships between ventilation rate and the perceived indoor air quality. A sensory panel assessed the air quality in test rooms ventilated with realistic outdoor air supply rates, where combinations of high- and low-polluting wall, floor and ceiling materials were set up. These materials were ranked as high- and low-polluting using sensory assessments of air quality in small-scale glass chambers, where they were tested individually. Substituting materials ranked as high-polluting with materials ranked as lower-polluting improved the perceived air quality in the test rooms. This improvement was greater than what was achieved by a realistic increase of the ventilation rate in the test rooms. Thus reducing pollution emitted from building materials that affects the perceived air quality has a considerable potential of limiting the energy for ventilation without compromising indoor air quality. (au)

  11. A numerical study of external building walls containing phase change materials (PCM)

    International Nuclear Information System (INIS)

    Phase Change Materials (PCMs) have been receiving increased attention, due to their capacity to store large amounts of thermal energy in narrow temperature ranges. This property makes them ideal for passive heat storage in the envelopes of buildings. To study the influence of PCMs in external building walls, a one-dimensional transient heat transfer model has been developed and solved numerically using a finite difference technique. Different external building wall configurations were analyzed for a typical building wall by varying the location of the PCM layer, the orientation of the wall, the ambient conditions and the phase transition temperature of the PCM. The integration of a PCM layer into a building wall diminished the amplitude of the instantaneous heat flux through the wall when the melting temperature of the PCM was properly selected according to the season and wall orientation. Conversely, the results of the work show that there is no significant reduction in the total heat lost during winter regardless of the wall orientation or PCM transition temperature. Higher differences were observed in the heat gained during the summer period, due to the elevated solar radiation fluxes. The high thermal inertia of the wall implies that the inclusion of a PCM layer increases the thermal load during the day while decreasing the thermal load during the night. - Highlights: ► A comparative simulation of a building wall with and without PCMs has been conducted. ► PCM is selected according with the season, the wall orientation and the melting temperature. ► PCM in a building wall help to diminish the internal air temperature swings and to regulate the heat transfer.

  12. Polyester-Based (Bio)degradable Polymers as Environmentally Friendly Materials for Sustainable Development

    OpenAIRE

    Joanna Rydz; Wanda Sikorska; Mariya Kyulavska; Darinka Christova

    2014-01-01

    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 vie...

  13. 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

  14. Structural performance evaluation on aging underground reinforced concrete structures. Part 1. Modeling of material degradation due to reinforcing steel corrosion

    International Nuclear Information System (INIS)

    This paper discusses effects of reinforcing steel corrosion on material properties of reinforced concrete and modeling of material degradation due to reinforcing steel corrosion used in a finite element method for structural analysis. First, we conducted a series of double-action tension tests on reinforced concrete specimens that were artificially corroded by stay current corrosion. We showed that the degradation ratio of yield strength of reinforcing steel agreeded well with maximum steel corrosion ratio and that tension softening of concrete became larger with the increase of corrosion degree. Second, based on these observations, reinforcement section area loss and initial tension strain due to reinforcement corrosion, a decrease in bond stress between reinforcement and concrete were employed for constructing the material model. To validate the devised modeling, the above -mentioned test results were numerically correlated. As a result, the analyzed load-strain relationships agreeded well with the experimental results under the condition of corrosion ratio 0-20%. Finally, as an application of experimental an analytical findings, we developed relationships between the parameters of modeling of material degradation and chloride induced deterioration progress as it widely accepted in maintenance practice for civil engineering reinforced concrete structures. (author)

  15. Influence of temperature on formaldehyde emission parameters of dry building materials

    Science.gov (United States)

    Zhang, Yinping; Luo, Xiaoxi; Wang, Xinke; Qian, Ke; Zhao, Rongyi

    The diffusion coefficient, D, partition coefficient, K, and the initial volatile organic compounds (VOCs) in dry building materials, are the three key parameters used to predict the VOC emissions. D and K may be strongly affected by temperature. We have developed a new and simple method, the C-history method, to measure the diffusion coefficient, D and the partition coefficient, K of formaldehyde in dry building materials at temperatures of 18, 30, 40 and 50 °C. The measured variations of the diffusion coefficients and the partition coefficients with temperature for particle board, vinyl floor, medium- and high-density board are presented. A formula relating the partition coefficient and related factors is obtained through analysis. This formula can predict the partition coefficient in principle and provide an insight for fitting experimental data, and it agrees well with the experimental results.

  16. Using Technology To Support Proactive Management Of Materials Degradation For The U.S. Nuclear Regulatory Commission

    International Nuclear Information System (INIS)

    The majority of the U.S. reactor fleet is applying for license renewal to extend the operating life from the current 40 years to 60 years, and there is now active interest in extending the operating life to beyond 60 years. Many plants are also applying for increases in power rating and both of these changes increases the need for an improved understanding of materials degradation. Many materials degrade over time and much is known about the degradation of materials under normal environmental conditions; however, less is known about the characteristics of materials degradation when the environment is subject to higher than normal radiological conditions over extended periods of time. Significant efforts are being made by industrial, academic and regulatory groups worldwide to identify, classify and mitigate potential problems arising from degradation of components in this context. From a regulatory perspective, the U.S. Nuclear Regulatory Commission (USNRC) is very interested in being able to identify ways to insure their licensees proactively manage the identification of materials degradation and the mitigation of its effects. To date, the USNRC has consolidated 'generic' programs for mitigating aging issues in the two volume Generic Aging Lessons Learned (GALL) Report (NUREG-1801), and have encouraged applicants for license renewal to use these programs where applicable in their plant when applying for renew of their reactor's license. The USNRC has also published a comprehensive report entitled Expert Panel Report on Proactive Materials Degradation (NUREG/CR-6923) that inventories the types of degradation mechanisms that could exist in each component of a Light Water Reactor (LWR) and each degradation mechanism is assessed regarding how much is known about mitigating its effects. Since the number of plant designs and materials used varies greatly within the U.S. fleet, there are many variations to implementing aging management programs (AMPs), requiring

  17. Beyond the red queen syndrome: CRM technology and building material suppliers

    OpenAIRE

    Love, PED; Edwards, DJ; Standing, C; Z Irani

    2009-01-01

    Purpose – Many businesses operating in the construction and engineering sector have been trying to respond to the demands being imposed on them by utilising information technology applications such as CRM and ERP, but immediate benefits and improvements in business performance have not been forthcoming. This paper aims to provide building material suppliers with the underlying knowledge to improve their business performance and customer relationships. Design/methodology/approach – A struc...

  18. 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 ...

  19. Investigation of photon attenuation coefficient of some building materials used in Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Dogan, B.; Altinsoy, N. [Istanbul Technical University (ITU), Institute of Energy, Ayazaga Kampusu, 34469, Istanbul, Turkey brhndgn@hotmail.com, altinsoy@itu.edu.tr (Turkey)

    2015-03-30

    In this study, some building materials regularly used in Turkey, such as concrete, gas concrete, pumice and brick have been investigated in terms of mass attenuation coefficient at different gamma-ray energies. Measurements were carried out by gamma spectrometry containing NaI(Tl) detector. Narrow beam gamma-ray transmission geometry was used for the attenuation measurements. The results are in good agreement with the theoretical calculation of XCOM code.

  20. Hygrothermal modelling of Lime-Hemp concrete used as building material and indoor climate buffering characterization

    OpenAIRE

    Dubois, Samuel; Evrard, Arnaud; Lebeau, Frédéric

    2012-01-01

    Hygroscopic building materials can affect the indoor air by exchanging moisture with it and buffering the ambient humidity variations. The Nordtest protocol and the concomitant Moisture Buffer Value (MBV) parameter definition has been one of the first attempt to characterize this moisture regulation performance. This paper present an attempt to confront this well-established experimental protocol with a mathematical model implemented in the Comsol mul...