WorldWideScience

Sample records for building materials degradation

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

    Science.gov (United States)

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

    2008-07-01

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

  2. Degradation of implant materials

    CERN Document Server

    Eliaz, Noam

    2012-01-01

    This book surveys the degradation of implant materials, reviewing in detail such failure mechanisms as corrosion, fatigue and wear, along with monitoring techniques. Surveys common implant biomaterials, as well as procedures for implant retrieval and analysis.

  3. Trends in building materials

    CSIR Research Space (South Africa)

    Mapiravana, Joseph

    2012-07-01

    Full Text Available of light-weight ultra-high performance concretes, Portland cement replacement, cement matrix and polymer matrix composites, recycling and reuse of waste materials, smart building materials, nanotechnology materials, green energy efficient building... on cement and concrete, composites, waste recycling and reuse and recently nanotechnology materials. To significantly impact on cost reduction and delivery lead time, it is recommended that building materials research and development priorities...

  4. Building Materials in Arctic Climate

    DEFF Research Database (Denmark)

    Jensen, Ole Mejlhede

    2005-01-01

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

  5. Mycotoxins in building materials

    DEFF Research Database (Denmark)

    Nielsen, Kristian Fog; Frisvad, Jens Christian

    2011-01-01

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

  6. 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...

  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. Biocide Runoff from Building Facades: Degradation Kinetics in Soil.

    Science.gov (United States)

    Bollmann, Ulla E; Fernández-Calviño, David; Brandt, Kristian K; Storgaard, Morten S; Sanderson, Hans; Bester, Kai

    2017-04-04

    Biocides are common additives in building materials. In-can and film preservatives in polymer-resin render and paint, as well as wood preservatives are used to protect facade materials from microbial spoilage. Biocides leach from the facade material with driving rain, leading to highly polluted runoff water (up to several mg L -1 biocides) being infiltrated into the soil surrounding houses. In the present study the degradation rates in soil of 11 biocides used for the protection of building materials were determined in laboratory microcosms. The results show that some biocides are degraded rapidly in soil (e.g., isothiazolinones: T 1/2 degradation products, respectively. The terbutryn mass balance could be closed over the entire study period of 120 days and showed that relative persistent metabolites were formed, while the mass balances for octylisothiazolinone could not be closed. Octylisothiazolinone degradation products did not accumulate over time suggesting that the missing fraction was mineralized. Microtox-tests revealed that degradation products were less toxic toward the bacterium Aliivibrio fischeri than their parent compounds. Rain is mobilizing these biocides from the facades and transports them to the surrounding soils; thus, rainfall events control how often new input to the soil occurs. Time intervals between rainfall events in Northern Europe are shorter than degradation half-lives even for many rapidly degraded biocides. Consequently, residues of some biocides are likely to be continuously present due to repeated input and most biocides can be considered as "pseudo-persistent"-contaminants in this context. This was verified by (sub)urban soil screening, where concentrations of up to 0.1 μg g -1 were detected for parent compounds as well as terbutryn degradation products in soils below biocide treated facades.

  9. Material Efficiency of Building Construction

    Directory of Open Access Journals (Sweden)

    Antti Ruuska

    2014-07-01

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

  10. 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....

  11. Recovery technologies for building materials

    Science.gov (United States)

    Karu, Veiko; Nurme, Martin; Valgma, Ingo

    2015-04-01

    Mining industry provides building materials for construction. Civil engineers have settled the quality parameters for construction materials. When we produce high quality building materials from carbonate rock (limestone, dolostone), then the estimated waste share is 25% to 30%, depending on crushing principles and rock quality. The challenge is to find suitable technology for waste recovery. During international mining waste related cooperation project MIN-NOVATION (www.min-novation.eu), partners mapped possibilities for waste recovery in mining industry and pointed out good examples and case studies. One example from Estonia showed that when we produce limestone aggregate, then we produce up to 30% waste material (fines with size 0-4mm). This waste material we can see as secondary raw material for building materials. Recovery technology for this fine grained material has been achieved with CDE separation plant. During the process the plant washes out minus 63 micron material from the limestone fines. This technology allows us to use 92% of all limestone reserves. By-product from 63 microns to 4 mm we can use as filler in concrete or as fine limestone aggregate for building or building materials. MIN-NOVATION project partners also established four pilot stations to study other mineral waste recovery technologies and solutions. Main aims on this research are to find the technology for recovery of mineral wastes and usage for new by-products from mineral mining waste. Before industrial production, testing period or case studies are needed. This research is part of the study of Sustainable and environmentally acceptable Oil shale mining No. 3.2.0501.11-0025 http://mi.ttu.ee/etp and the project B36 Extraction and processing of rock with selective methods - http://mi.ttu.ee/separation; http://mi.ttu.ee/miningwaste/

  12. Frost resistance of building materials

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan De Place

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

  13. Daylight as a building material

    DEFF Research Database (Denmark)

    Thule Kristensen, Peter; Madsen, Merete

    2005-01-01

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

  14. Wood: a construction material for tall buildings

    Science.gov (United States)

    Wimmers, Guido

    2017-12-01

    Wood has great potential as a building material, because it is strong and lightweight, environmentally friendly and can be used in prefabricated buildings. However, only changes in building codes will make wood competitive with steel and concrete.

  15. A storey of buildings and materials

    Science.gov (United States)

    2017-12-01

    Throughout history, the development of new materials and technologies has enabled more functional and aesthetically pleasing buildings. With the advent of sustainable architecture, the role of materials science in building innovation is becoming more prominent than ever.

  16. Preservation of adobe buildings. Study of materials

    Science.gov (United States)

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

    2012-04-01

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

  17. 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

  18. Quartzite of historic buildings in Brazil: designations and degradation patterns

    Science.gov (United States)

    Costa, Antônio

    2015-04-01

    Quartzite dated with ages between 2.60 and 1.75 Ga were used in historic buildings in Brazil, almost exclusively in Minas Gerais. Dating from the eighteenth and nineteenth centuries, these buildings can be viewed in the cities of Ouro Preto and Tiradentes, as well as part of the architectural complex of the old Colégio Caraça, located in the homonymous ridge. Here, the quartzite used is the oldest (approx. 2.60 Ga). Designated as Cambotas, the material crops out in the vicinity of the complex. On the other hand those quartzite used in the constructions in Ouro Preto are stratigraphically from the Moeda Formation (between 2.6 and 2.56 Ga), or from Itacolomy Group (between 2.12 and 1.75 Ga). The first, designated Lajes, is exposed in the Ouro Preto Ridge, while the second, designated Itacolomy, crops out in the homonymous ridge. In buildings of Tiradentes were employed quartzites with ages also from Lower Proterozoic. They belong to the Tiradentes Formation and are exposed in the São José Ridge, near the city. In these regions, where these monuments were built, the metamorphic rocks of sedimentary origin predominate and it can be affirmed that resulted from a low-grade metamorphism (schists and phyllites from the greenschist facies). The quartzite occur associate and consist essentially of quartz, but may show different contents of accessory minerals such as mica, kyanite and opaque minerals (iron oxides). Depending on the content of mica can show planar structures. Structures of the sediment phase can still be observed, such as banding by compositional variation or other such as cross bedding. The different degradation patterns of these quartzite occur singly or in combinations and were influenced by the textures and structures of these rocks. From all those patterns, the most common has to do with chromatic modifications of the stone materials (patina) occurred due to varying degrees of oxidation and formation of hydroxides. Because of this, the quartzite can

  19. MOISTURE-BUFFERING CHARACTERISTICS OF BUILDING MATERIALS

    Directory of Open Access Journals (Sweden)

    Young Cheol Choi

    2016-05-01

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

  20. SYSTEM ORGANIZATION OF MATERIAL PROVIDING OF BUILDING

    Directory of Open Access Journals (Sweden)

    A. V. Rаdkеvich

    2014-04-01

    Full Text Available Purpose. Development of scientific-methodical bases to the design of rational management of material streams in the field of building providing taking into account intersystem connections with the enterprises of building industry. Methodology. The analysis of last few years of functioning of building industry in Ukraine allows distinguishing a number of problems that negatively influence the steady development of building, as the component of the state economics system. Therefore the research of existent organization methods of the system of building objects providing with material resources is extremely necessary. In connection with this the article justifies the use of method of hierarchies analysis (Saati method for finding the optimal task solution of fixing the enterprises of building industry after building objects. Findings. Results give an opportunity to guidance of building organization to estimate and choose advantageous suppliers - enterprises of building industry, to conduct their rating, estimation taking into account basic descriptions, such as: quality, price, reliability of deliveries, specialization, financial status etc. Originality. On the basis of Saati method the methodologies of organization are improved, planning and managements of the reliable system of providing of building necessary material resources that meet the technological requirements of implementation of building and installation works. Practical value. Contribution to the decisions of many intricate organizational problems that are accompanied by the problems of development of building, provided due to organization of the reliable system of purchase of material resources.

  1. Wood as a sustainable building material

    Science.gov (United States)

    Robert H. Falk

    2010-01-01

    Few building materials possess the environmental benefits of wood. It is not only our most widely used building material but also one with characteristics that make it suitable for a wide range of applications. As described in the many chapters of this handbook, efficient, durable, and useful wood products produced from trees can range from a minimally processed log at...

  2. Phase Change Materials in the building industry

    NARCIS (Netherlands)

    De Haan, H.

    2011-01-01

    This paper is written for the TIDO-course AR0532 Smart & Bioclimatic Design Theory. In this paper is focused on the application of 'phase changing materials' (PCMs) in buildings as a design strategy that deploys local characteristics intelligently into the sustainable design of buildings. This

  3. Synthetic building materials for transport buildings and structures

    Science.gov (United States)

    Gerasimova, Vera

    2017-10-01

    The most effective building materials account for the highest growth not only in construction of residential and public buildings, but also other capital projects including roadways, bridges, drainage, communications and other engineering projects. Advancement in the technology of more efficient and ecologically responsible insulation materials have been a priority for safety, minimal maintenance and longevity of finished construction projects. The practical use of modern building materials such as insulation, sound reduction and low energy consumption are a benefit in cost and application compared to the use of outdated heavier and labor-intensive materials. The most efficient way for maximizing insolation and sound proofing should be done during the design stages of the project according to existing codes and regulations that are required by Western Government. All methods and materials that are used need to be optimized in order to reach a high durability and low operational and maintenance cost exceeding more than 50 years of the life of the building, whether it is for public, industrial or residential use. Western construction techniques and technologies need to be applied and adapted by the Russian Federation to insure the most productive successful methods are being implemented. The issues of efficient insulation materials are outlined in this article.

  4. 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

  5. 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....

  6. Sodium chloride damage to porous building materials

    NARCIS (Netherlands)

    Lubelli, B.A.

    2006-01-01

    This research studied sodium chloride (NaCl) damage to porous building materials with the aim of: i) gaining a better understanding of the damage process and ii) developing an effective crystallization test. It has been definitely proven that NaCl modifies the hygric dilation of a material

  7. Handbook of environmental degradation of materials

    National Research Council Canada - National Science Library

    Kutz, Myer

    2012-01-01

    Divided into sections which deal with analysis, types of degradation, protection and surface engineering respectively, the reader is introduced to the wide variety of environmental effects and what...

  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. 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....... Accelerated degradation by concentrated light thus allows for rapid and precise evaluations of one sun polymer stabilities....

  10. Characteristic Analysis of Building Surface Material Combination

    Science.gov (United States)

    Wang, Yao

    2018-01-01

    To study the composition of building materials, the composition and characteristics of building surface materials are analyzed. Based on the MPIRAN algorithm, 157 sets of samples are selected, of which 130 are used for study and the 27 is used for verification. Before modeling, all the sample inputs are normalized to the [0,1] range, and the mean error function is used to test the output error of the network. The commonly used RAN learning algorithm is compared with MPIRAN to verify its superiority. The simulation results show that MPIRAN learning algorithm is suitable for the classification of building materials. Compared with the other learning methods, it can also significantly reduce the number of hidden nodes in the network. Based on the above findings, it is concluded that the MPIRAN algorithm can reduce the network structure and improve the learning ability and calibration ability of the network, so that the correct classification of samples can be realized.

  11. 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.

  12. 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...... 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...... coefficient is defined which can be determined based on measured drying data. The correlation of this coefficient with the water absorption and the vapour diffusion coefficient is analyzed and its additional information content is critically challenged. As result, a drying coefficient has been derived...

  13. 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.

  14. 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...... 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...

  15. Radioisotopes present in building materials of workplaces

    Science.gov (United States)

    Del Claro, F.; Paschuk, S. A.; Corrêa, J. N.; Denyak, V.; Kappke, J.; Perna, A. F. N.; Martins, M. R.; Santos, T. O.; Rocha, Z.; Schelin, H. R.

    2017-11-01

    The isotope 222Rn is responsible for approximately half of the effective annual dose received by the world population. The decay products of 222Rn interacting with the cells of biological tissue of lungs have very high probability to induce cancer. The present survey was focused in the evaluation of activity concentration of 222Rn and other radioisotopes related to the building materials at workplaces at Curitiba - Paraná State. For this purpose, the instant radon detector AlphaGUARD (Saphymo GmbH) was used to measure the average concentrations of 222Rn in building materials, which were also submitted to gamma spectrometry analysis for qualitative and quantitative evaluation of the radionuclides present in samples of sand, mortar, blue crushed stone (Gneissic rock), red crushed stone (Granite), concrete and red bricks. The main radionuclides evaluated by gamma spectrometry in building material samples were 238U/226Ra, 232Th and 40K. These measurements were performed at the Laboratory of Applied Nuclear Physics of the Federal University of Technology - Paraná in collaboration with the Center of Nuclear Technology Development (CDTN - CNEN). The results of the survey present the concentration values of 222Rn related to construction materials in a range from 427±40.52 Bq/m³ to 2053±90.06 Bq/m³. The results of gamma spectroscopy analysis show that specific activity values for the mentioned isotopes are similar to the results indicated by the literature. Nevertheless, the present survey is showing the need of further studies and indicates that building materials can contribute significantly to indoor concentration of 222Rn.

  16. Assessing sustainability of building materials in developing countries: the sustainable building materials index (SBMI)

    CSIR Research Space (South Africa)

    Gibberd, Jeremy T

    2014-10-01

    Full Text Available Measuring sustainability of building materials is complex. Despite this a wide range of different methodologies and systems have been developed. Most of these focus on environmental issues and are based on Life Cycle Assessment (LCA), or similar...

  17. Environmental degradation of advanced and traditional engineering materials

    National Research Council Canada - National Science Library

    Hihara, Lloyd H; Adler, Ralph P. I; Latanision, Ronald M

    2014-01-01

    "From metals and polymers to ceramics, natural materials, and composites, this book covers the environmental impacts on a broad range of materials used for the engineering of infrastructure, buildings...

  18. Radiation degradation of plastic insulating materials

    Energy Technology Data Exchange (ETDEWEB)

    Bartonicek, B.; Hnat, V.; Janovsky, I.; Pejsa, R. [Nuclear Research Institute, Rez (Czech Republic)

    1995-10-01

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

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

    NARCIS (Netherlands)

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

    2011-01-01

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

  20. ICAN Computer Code Adapted for Building Materials

    Science.gov (United States)

    Murthy, Pappu L. N.

    1997-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Cho, M. S.; Song, Y. C. [KEPRI, Taejon (Korea, Republic of); Yim, J. H. [KEPCO, Seoul (Korea, Republic of); Kim, D. K.; Lee, J. S. [KICT, Seoul (Korea, Republic of)

    2001-05-01

    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{center_dot}SIT{center_dot}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.

  2. 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...... 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...... 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...

  3. Metamaterials and Plasmonics: Improved Material Building Blocks

    Science.gov (United States)

    Boltasseva, Alexandra

    2012-02-01

    Optical metamaterials are rationally designed and manufactured materials built of nanostructured unit cells, or ``artificial atoms'' much smaller than the wavelength of operating light. These materials can be engineered to exhibit optical properties beyond any naturally occurring materials. This field has been gaining momentum over the past several years, as it continues to provide new fascinating ideas promising a variety of exciting applications including for example super-resolution microscopes, extremely efficient light concentrators and invisibility cloaks. In most metamaterial devices, noble metals (primarily gold and silver) have been used as the constituent material to make subwavelength building blocks. But metals suffer from high optical losses that are much too large to create practical and robust metamaterials devices. A recent approach that could unlock the technological potential of plasmonics and optical metamaterials is to look for better plasmonic materials that have a negative real part of dielectric permittivity. Here we provide an overview of two classes of alternative plasmonic materials - doped semiconductors and intermetallics - that could allow realization of novel transformation optics and metamaterial devices with greatly improved performance operating at near infrared and visible frequencies.

  4. Overview of NRC Proactive Management of Materials Degradation (PMMD) Program

    Science.gov (United States)

    Carpenter, C. E. Gene; Hull, Amy; Oberson, Greg

    Materials degradation phenomena, if not appropriately managed, have the potential to adversely impact the design functionality and safety margins of nuclear power plant (NPP) systems, structures and components (SSCs). Therefore, the U.S. Nuclear Regulatory Commission (NRC) has initiated an over-the-horizon multi-year research Proactive Management of Materials Degradation (PMMD) Research Program, which is presently evaluating longer time frames (i.e., 80 or more years) and including passive long-lived SSCs beyond the primary piping and core internals, such as concrete containment and cable insulation. This will allow the NRC to (1) identify significant knowledge gaps and new forms of degradation; (2) capture current knowledge base; and, (3) prioritize materials degradation research needs and directions for future efforts. This effort is being accomplished in collaboration with the U.S. Department of Energy's (DOE) LWR Sustainability (LWRS) program. This presentation will discuss the activities to date, including results, and the path forward.

  5. Environmental impacts of adobe as a building material: The north cyprus traditional building case

    Directory of Open Access Journals (Sweden)

    A.P. Olukoya Obafemi

    2016-06-01

    Summarily, this paper posits that the successful fusion of traditional building materials such as Adobe and modern design construct will not only give birth to earth conscious building, but will also be energy efficient. Moreover, it will be a substitute building material the building industry can adopt at as a contributing solution to the omniscient global warming malady.

  6. Building biomedical materials using photochemical bond cleavage.

    Science.gov (United States)

    Bao, Chunyan; Zhu, Linyong; Lin, Qiuning; Tian, He

    2015-03-11

    Light can be used as an external trigger to precisely determine where and when a process is initiated as well as how much of the process is being consumed. Phototriggers are a type of photoresponsive functional group that undergo an irreversible photolysis reaction by selectively breaking a chemical bond, enabling three fundamental functions: the photoactivation of fluorescent and bioactive molecules; the photocleavable degradation of macromolecular materials; and the photorelease of drugs, active groups, or surface charges from carriers and interfaces. With the expanded applications of light-controlled technology, particularly in living systems, new challenges and improvements of phototriggers are required to fulfill the demands for better sensitivity, faster kinetics, and more-demanding biomedical applications. Here, improvements to several conventional phototriggers are highlighted, and their notable, representative biomedical applications and their challenges are discussed. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. 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

  8. 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.

  9. 10 CFR 434.402 - Building envelope assemblies and materials.

    Science.gov (United States)

    2010-01-01

    ... design condition. For shell buildings, the permitted skylight area shall be based on a light level of 30... 10 Energy 3 2010-01-01 2010-01-01 false Building envelope assemblies and materials. 434.402... MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Building Design Requirements-Electric Systems and Equipment...

  10. Environmental impacts of adobe as a building material: The north cyprus traditional building case

    OpenAIRE

    A.P. Olukoya Obafemi; Sevinç Kurt

    2016-01-01

    The urgency of global climate change has drawn significant attention to the building industry over the last few years. Today, the building sector is responsible for the emission of about 23–40% of the world greenhouse gases. This is plausible owing to the various non environmental friendly materials used by modern building industry and the palpable contemporary design construct. Unlike modern buildings, traditional building materials are proven to be earth conscious and have nearly zero carbo...

  11. Flammability tests for regulation of building and construction materials

    Science.gov (United States)

    K. Sumathipala

    2006-01-01

    The regulation of building materials and products for flammability is critical to ensure the safety of occupants in buildings and other structures. The involvement of exposed building materials and products in fires resulting in the loss of human life often spurs an increase in regulation and new test methods to address the problem. Flammability tests range from those...

  12. Organic Materials Degradation in Solid State Lighting Applications

    NARCIS (Netherlands)

    Yazdan Mehr, M.

    2015-01-01

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

  13. 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.

  14. 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....

  15. 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.

  16. 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.

  17. 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

  18. 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.

  19. Neutron activation analysis of some building materials

    Science.gov (United States)

    Salagean, M. N.; Pantelica, A. I.; Georgescu, I. I.; Muntean, M. I.

    1999-01-01

    Concentrations of As, Au, Ba, Br, Ca, Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Mo, Na, Nd, Rb, Sb, Sc, Sr, Ta, Tb, Th, U. Yb, W and Zn in seven Romanian building materials were determined by the Instrumental Neutron Activation Analysis (INAA) method using the VVR-S Reactor of NIPNE- Bucharest. Raw matarials used in cement obtaining ≈ 75% of limestone and ≈ 25% of clay, cement samples from three different factories, furnace slag, phosphogypsum, and a type of brick have been analyzed. The brick was compacted from furnace slay, fly coal ash, phosphogypsum, lime and cement. The U, Th and K concentrations determined in the brick are in agreement with the natural radioactivity measurements of226Ra,232Th and40K. These specific activities were found about twice and 1.5 higher than the accepted levels in the case of226Ra and232Th, as well as40K, respectively. By consequence, the investigated brick is considered a radioactive waste. The rather high content of Co, Cr, K, Th, and Zh in the brick is especially due to the slag and fly ash, the main componets. The presence of U, Th and K in slag is mainly correlated with the limestone and dolomite as fluxes in matallurgy.

  20. Radioactivity of buildings materials available in Slovakia

    Science.gov (United States)

    Singovszka, E.; Estokova, A.; Mitterpach, J.

    2017-10-01

    In the last decades building materials, both of natural origin and containing industrial by-products, have been shown to significantly contribute to the exposure of the population to natural radioactivity. As a matter of fact, neither the absorbed dose rate in air due to gamma radiation nor the radon activity concentration are negligible in closed environments. The soil and rocks of the earth contains substances which are naturally radioactive and provide natural radiation exposures. The most important radioactive elements which occur in the soil and in rocks are the long lived primordial isotopes of potassium (40K), uranium (238U) and thorium (232Th). Therefore, additional exposures have to be measured and compared with respect to the natural radiation exposure. Further, it is important to estimate the potential risk from radiation from the environment. The paper presents the results of mass activities of 226Ra, 232Th a 40K radionuclides in cement mortars with addition of silica fume. The gamma index was calculated as well.

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

    Directory of Open Access Journals (Sweden)

    Márcio Antonio Paraizo

    2004-12-01

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

  2. Degradation of cementitious materials associated with salstone disposal units

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-09-01

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

  3. Durability of Building Materials Vol 4

    DEFF Research Database (Denmark)

    Howard, Rob

    1999-01-01

    Facility management has become another business management discipline and the transfer of building data from design and construction into management has been neglected. The needs of building managers need to be specified and standardised to aallow designers to provide data in the form required....

  4. 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).

  5. Measurement of radon exhalation rate in various building materials ...

    Indian Academy of Sciences (India)

    Indoor radon is considered as one of the potential dangerous radioactive elements. Common building materials and soil are the major source of this radon gas in the indoor environment. In the present study, the measurement of radon exhalation rate in the soil and building material samples of Una and Hamirpurdistricts of ...

  6. Boosting LPMO-driven lignocellulose degradation by polyphenol oxidase-activated lignin building blocks.

    Science.gov (United States)

    Frommhagen, Matthias; Mutte, Sumanth Kumar; Westphal, Adrie H; Koetsier, Martijn J; Hinz, Sandra W A; Visser, Jaap; Vincken, Jean-Paul; Weijers, Dolf; van Berkel, Willem J H; Gruppen, Harry; Kabel, Mirjam A

    2017-01-01

    Many fungi boost the deconstruction of lignocellulosic plant biomass via oxidation using lytic polysaccharide monooxygenases (LPMOs). The application of LPMOs is expected to contribute to ecologically friendly conversion of biomass into fuels and chemicals. Moreover, applications of LPMO-modified cellulose-based products may be envisaged within the food or material industry. Here, we show an up to 75-fold improvement in LPMO-driven cellulose degradation using polyphenol oxidase-activated lignin building blocks. This concerted enzymatic process involves the initial conversion of monophenols into diphenols by the polyphenol oxidase MtPPO7 from Myceliophthora thermophila C1 and the subsequent oxidation of cellulose by MtLPMO9B. Interestingly, MtPPO7 shows preference towards lignin-derived methoxylated monophenols. Sequence analysis of genomes of 336 Ascomycota and 208 Basidiomycota reveals a high correlation between MtPPO7 and AA9 LPMO genes. The activity towards methoxylated phenolic compounds distinguishes MtPPO7 from well-known PPOs, such as tyrosinases, and ensures that MtPPO7 is an excellent redox partner of LPMOs. The correlation between MtPPO7 and AA9 LPMO genes is indicative for the importance of the coupled action of different monooxygenases in the concerted degradation of lignocellulosic biomass. These results will contribute to a better understanding in both lignin deconstruction and enzymatic lignocellulose oxidation and potentially improve the exploration of eco-friendly routes for biomass utilization in a circular economy.

  7. Directory of wood-framed building deconstruction and reused wood building materials companies, 2004

    Science.gov (United States)

    Robert H. Falk; G. Bradley Guy

    2004-01-01

    This is a directory of companies involved in wood-framed building deconstruction, dismantling and reused building materials, with an emphasis on those that use, resell, and/or re-manufacture salvaged wood. Companies in this directory range in scope from those that carryout targeted building removals, such as historic barns, strictly for the purpose of harvesting the...

  8. 29 CFR 779.335 - Sales of building materials for residential or farm building construction.

    Science.gov (United States)

    2010-07-01

    ... residential or farm building, repair or maintenance is not a sale for resale, provided, the sale is otherwise... 29 Labor 3 2010-07-01 2010-07-01 false Sales of building materials for residential or farm building construction. 779.335 Section 779.335 Labor Regulations Relating to Labor (Continued) WAGE AND...

  9. Developing an environmental performance standard for the materials in buildings for the Dutch Building Decree

    NARCIS (Netherlands)

    Scholten, N.P.M.; Groot-Van Dam, A. de; Kortman, J.G.M.; Huppes, G.; Ven, B. van der; Schuurmans, A.; Anink, D.

    2001-01-01

    After consulting the building industry the Dutch government decided in February 1998 to implement sustainability requirements in the Dutch Building Decree by the year 2001. Part of these requirements will be the material-based environmental performance of a building, mepb.. An energy performance

  10. Detection of ciliostatic activity in fungal growth on building materials.

    Science.gov (United States)

    Wilkins, Ken; Piecková, Elena

    2002-01-01

    Varying ciliostatic activity was found in extracts of biomass from building materials inoculated with pure isolates of some molds previously isolated from buildings. Extracts from growth on materials composed of finely divided cellulose (plaster board and construction cardboard) were more active than those from growth on Rockwool. Extracts of biomass from all three materials demonstrated an activity greater than control samples. Based on the activity observed here, it is conceivable that the measurement of ciliostatic activity of biomass scraped from contaminated building materials could be useful for planning removal strategies.

  11. Gneisses of Brazil's cultural heritage buildings and its most frequent degradations

    Science.gov (United States)

    Gilberto Costa, Antônio

    2017-04-01

    Macroscopic descriptions of cultural heritage buildings constructed using gneisses in the cities of Rio de Janeiro, Belo Horizonte and Ouro Preto, Brazil, allowed to identify alterations and degradations, in part conditioned by the mineralogical composition and the structures present in these stone materials. It is important to emphasize that: - some changes still begin in the environments where these materials were formed, experiencing an intensification from the processes of extraction, processing and application; - modifications occurring after the applications are understood herein as degradations. The studied gneisses present banding consisting of parts with different thicknesses and mineralogical contents. Due to these differentiated contents, clear bands were identified and constituted essentially by felsic minerals, such as feldspars and quartz, as well as dark bands formed by mafic minerals represented by: biotite, garnets, amphiboles, such as hornblende or pyroxene (hyperstene). In addition to these minerals, low contents of oxides and sulphides were found. Also under the influence of this distribution of minerals, planar structures or foliations, more or less developed, that can be very penetrative have been identified, mainly when these rocks were submitted to the performance of milonitization processes. From the set of changes and degradations observed stand out those related to the decomposition of minerals that make up these materials. In these cases, feldspars and other silicates, such as micas, amphiboles and pyroxenes, were decomposed due to the hydrolysis and products were generated which compromised the resistance of these stone materials, leading to their consequent disintegration. On the other hand, the presence of expansive clays in these products, caused volume increases which also contributed to the expansion of the weathered surface layer (blistering). This process may result detachments in the form of scales to cavities in cases of

  12. Research Progress of Building Materials Used in Construction Land

    Science.gov (United States)

    Niu, Yan

    2018-01-01

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

  13. WastePD, an innovative center on materials degradation

    Energy Technology Data Exchange (ETDEWEB)

    Frankel, Gerald S.; Vienna, John; Lian, Jie

    2017-07-25

    The US Department of Energy recently awarded funds to create the Center for Performance and Design of Nuclear Waste Forms and Containers (WastePD) as part of the Energy Frontier Research Center (EFRC) program. EFRCs are multi-investigator collaborations of universities, national labs and companies that “conduct fundamental research focusing on one or more “grand challenges” and use-inspired “basic research needs” identified in major strategic planning efforts by the scientific community.” The major performance parameter of nuclear waste forms is their ability to isolate the radionuclides by withstanding degradation in a repository environment over very long periods of time. So WastePD is at heart a center focused on materials degradation.

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

    Science.gov (United States)

    Stephens, Suzanne

    1980-01-01

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

  15. Material characterization models and test methods for historic building materials

    DEFF Research Database (Denmark)

    Hansen, Tessa Kvist; Peuhkuri, Ruut Hannele; Møller, Eva B.

    2017-01-01

    Predictions of long term hygrothermal performance can be assessed by dynamic hygrothermal simulations, in which material parameters are crucial input. Material parameters for especially historic materials are often unknown; therefore, there is a need to determine important parameters, and simple...

  16. 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.

  17. 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.

  18. Sustainability of earth building materials - Environmental product declarations as an instrument of competition in building material industry

    Directory of Open Access Journals (Sweden)

    Horst Schroeder

    2015-12-01

    Full Text Available The evaluation of the building process in terms of their environmental impact in all life cycle phases of a building leads to the key principle of sustainable building: the analysis of the life cycle of the materials used in a building. The goal of this analysis is to reduce waste and keep the environmental impact as low as possible by “closing” the cycle. During an inventory, the entire life cycle is assessed. This includes the sourcing and extracting of the raw material, the use of the raw material to produce building products, elements and structures, the use in finished buildings including emission of pollutants, decay and maintenance, and, finally, the demolition of the building and the recycling of the demolition materials. Transportation between the individual phases as well as production-related material and energy flows are also included in this evaluation. Several European and national norms and regulations define core rules and a special instrument for the evaluation of the sustainable quality of a building product based on a quantitative analysis of the life cycle of the materials used in a building: the Environmental Product Declaration EPD. These documents are voluntary standards, commitments or guarantees for building products. They are provided by producers, organizations and quality assurance associations in order to establish the “environmental performance” of buildings in the form of a certificate. Such declarations must fully include all phases of the life cycle of a product by describing the environmental impact during production and use as well as possible health hazards for the users. Until now, EPDs for earth building products do not exist. This paper will give current information about a project for developing EPDs for earth mortars and earth blocks started by the German Dachverband Lehm e.V. (DVL.

  19. 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...

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

    Directory of Open Access Journals (Sweden)

    Fabio Bisegna

    2016-09-01

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

  1. Sensory ratings of emissions from nontraditional building materials

    DEFF Research Database (Denmark)

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

    2016-01-01

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

  2. 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. MARCH

  3. Degradation of Polymeric Material used for Osteosynthesis and Comparison of Fracture Toughness Between Test and FEA

    Directory of Open Access Journals (Sweden)

    Bijoy Paul

    2017-08-01

    Full Text Available Biodegradable polymers such as PLA, PGA, PLGA etc., inside the human body often pose a tough challenge for the orthopedic doctors and material scientists. Unlike metallic or ceramic implants, where deterioration of the mechanical properties has never been an issue, biodegradable polymeric implants, used for Osteosynthesis, deteriorate while the fractured bone is subjected to kinesiological stress during healing process. To understand how biodegradable materials lose its mechanical properties, an investigation into the influence of degradation process on Mode-I fracture toughness of poly (lactide-co-glycolide, PLGA 85:15 material was initiated. The objective of this study was to build an improved understanding of the deterioration of biodegradable polymers mechanical properties during in-vitro degradation and how this change may affect long term in-vivo performance of the implants. A simple mathematical relationship was established to understand the change in the Young’s modulus during the degradation process. Compact tension specimens were designed and molded for mode-I fracture criterion and then put in 3% concentrated Hydrogen peroxide (H2O2 to study the degradation process. FEA (Finite Element Analysis was used to study the change in mechanical properties and then the results were compared with the physical test. Mode-I fracture toughness, KIC was measured and the behavior of the polymer was also identified. It was seen that the fracture toughness, KIC of PLGA 85:15 decreased with the progression of degradation. Finally, it was concluded that an increase in the Young’s modulus made PLGA 85:15 very brittle and hence resulted in reduced fracture toughness.

  4. Assessment of the Effectiveness of Local Building Materials used for ...

    African Journals Online (AJOL)

    ... are not easily accessible. Consequently, it was recommended among others that people should avoid areas with clay soil, torrential flooding or slopes in order to minimize costs for special foundations and damp proofing elements. Key words: Assessment, effectiveness, local building materials and building construction ...

  5. Radiological evaluation of building materials used in Malumfashi ...

    African Journals Online (AJOL)

    The activity concentrations of naturally occurring radionuclides (226Ra, 232Th and 40K) in building materials (sand, cement, blocks, granite, and paints) used in the construction of buildings in Malumfashi local Government area of Katsina state, Nigeria were determined by means of a gamma-ray spectrometry system using ...

  6. Acid-degradable and bioerodible modified polyhydroxylated materials

    Energy Technology Data Exchange (ETDEWEB)

    Frechet, Jean M. J.; Bachelder, Eric M.; Beaudette, Tristan T.; Broaders, Kyle E.

    2017-05-09

    Compositions and methods of making a modified polyhydroxylated polymer comprising a polyhydroxylated polymer having reversibly modified hydroxyl groups, whereby the hydroxyl groups are modified by an acid-catalyzed reaction between a polydroxylated polymer and a reagent such as acetals, aldehydes, vinyl ethers and ketones such that the modified polyhydroxylated polymers become insoluble in water but freely soluble in common organic solvents allowing for the facile preparation of acid-sensitive materials. Materials made from these polymers can be made to degrade in a pH-dependent manner. Both hydrophobic and hydrophilic cargoes were successfully loaded into particles made from the present polymers using single and double emulsion techniques, respectively. Due to its ease of preparation, processability, pH-sensitivity, and biocompatibility, of the present modified polyhydroxylated polymers should find use in numerous drug delivery applications.

  7. 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

  8. Shielding effectiveness of original and modified building materials

    Directory of Open Access Journals (Sweden)

    T. Frenzel

    2007-06-01

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

  9. People, planet and profit: Unintended consequences of legacy building materials.

    Science.gov (United States)

    Zimmer, Anthony T; Ha, HakSoo

    2017-12-15

    Although an explosion of new building materials are being introduced into today's market, adequate up-front research into their chemical and physical properties as well as their potential health and environmental consequences is lacking. History has provided us with several examples where building materials were broadly deployed into society only to find that health and environmental problems resulted in unintended sustainability consequences. In the following paper, we use lead and asbestos as legacy building materials to show their similar historical trends and sustainability consequences. Our research findings show unintended consequences such as: increased remediation and litigation costs; adverse health effects; offshoring of related industries; and impediments to urban revitalization. As numerous new building materials enter today's market, another building material may have already been deployed, representing the next "asbestos." This paper also proposes an alternative methodology that can be applied in a cost-effective way into existing and upcoming building materials, to minimize and prevent potential unintended consequences and create a pathway for sustainable communities. For instance, our findings show that this proposed methodology could have prevented the unintended incurred sustainability costs of approximately $272-$359 billion by investing roughly $24 million in constant 2014 U.S. dollars on up-front research into lead and asbestos. Published by Elsevier Ltd.

  10. Corrosion Detection of Reinforcement of Building Materials with Piezoelectric Sensors

    Directory of Open Access Journals (Sweden)

    Jia Peng

    2017-06-01

    Full Text Available The extensive use of reinforced materials in the construction industry has raised increased concerns about their safety and durability, while corrosion detection of steel materials is becoming increasingly important. For the scientific management, timely repair and health monitoring of construction materials, as well as to ensure construction safety and prevent accidents, this paper investigates corrosion detection on construction materials based on piezoelectric sensors. At present, the commonly used corrosion detection methods include physical and electrochemical methods, but there are shortcomings such as large equipment area, low detection frequency, and complex operation. In this study an improved piezoelectric ultrasonic sensor was designed, which could not only detect the internal defects of buildings while not causing structural damage, but also realize continuous detection and enable qualitative and quantitative assessment. Corrosion detection of reinforced building materials with piezoelectric sensors is quick and accurate, which can find hidden dangers and provide a reliable basis for the safety of the buildings.

  11. 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.

  12. Glass-ceramics as building materials

    Directory of Open Access Journals (Sweden)

    Rincón, J. María

    1996-06-01

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

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

  13. Degradation study on optical materials for concentrator photovoltaics

    Science.gov (United States)

    Eltermann, Fabian; Roeder, Kerstin; Wiesenfarth, Maike; Wilde, Juergen; Bett, Andreas W.

    2012-10-01

    In this work the impact of accelerated aging on the spectral transmission and the mechanical robustness of silicone elastomers for concentrator photovoltaic applications was investigated. Therefore, specific test samples were manufactured. The samples were annealed at 150 °C to assure a complete cross-linking. These samples were exposed to humidity freeze, to a pressure cooker test, and to UV light. To investigate optical materials under UVA intensity up to 10 W/cm2 a test setup was developed. Thus, a UV dosage of 10000 kWh/m2 was applied to the silicone samples after thermal treatment. The mean transmission was used as a measure to identify changes in the spectral behavior and was, therefore, compared after the stress tests with the initial value. No total failures but rather degradation was observed, mainly in the range of ultraviolet and visible light. In addition, the shear strengths for the silicone elastomers were compared before and after stress.

  14. Degradation of metallic materials studied by correlative tomography

    Science.gov (United States)

    Burnett, T. L.; Holroyd, N. J. H.; Lewandowski, J. J.; Ogurreck, M.; Rau, C.; Kelley, R.; Pickering, E. J.; Daly, M.; Sherry, A. H.; Pawar, S.; Slater, T. J. A.; Withers, P. J.

    2017-07-01

    There are a huge array of characterization techniques available today and increasingly powerful computing resources allowing for the effective analysis and modelling of large datasets. However, each experimental and modelling tool only spans limited time and length scales. Correlative tomography can be thought of as the extension of correlative microscopy into three dimensions connecting different techniques, each providing different types of information, or covering different time or length scales. Here the focus is on the linking of time lapse X-ray computed tomography (CT) and serial section electron tomography using the focussed ion beam (FIB)-scanning electron microscope to study the degradation of metals. Correlative tomography can provide new levels of detail by delivering a multiscale 3D picture of key regions of interest. Specifically, the Xe+ Plasma FIB is used as an enabling tool for large-volume high-resolution serial sectioning of materials, and also as a tool for preparation of microscale test samples and samples for nanoscale X-ray CT imaging. The exemplars presented illustrate general aspects relating to correlative workflows, as well as to the time-lapse characterisation of metal microstructures during various failure mechanisms, including ductile fracture of steel and the corrosion of aluminium and magnesium alloys. Correlative tomography is already providing significant insights into materials behaviour, linking together information from different instruments across different scales. Multiscale and multifaceted work flows will become increasingly routine, providing a feed into multiscale materials models as well as illuminating other areas, particularly where hierarchical structures are of interest.

  15. Sensory ratings of emissions from nontraditional building materials

    DEFF Research Database (Denmark)

    Krejcirikova, Barbora; Kolarik, Jakub; Peuhkuri, Ruut

    2016-01-01

    Twenty-five subjects assessed the emissions from building materials: linoleum, cement mortar with and without fly ash, gypsum board and tiles with air cleaning properties and natural organic sheep wool. The ratings were made at different material loadings and in combinations with linoleum...

  16. 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.

  17. Indoor exposure from building materials: A field study

    Science.gov (United States)

    Missia, Dafni A.; Demetriou, E.; Michael, N.; Tolis, E. I.; Bartzis, J. G.

    2010-11-01

    The present study has been conducted in the frame of BUMA (Prioritization of Building Materials Emissions as indoor pollution sources), a European funded project, aiming at assessing the exposure to emitted compounds in indoor air. Field campaigns in five (5) European cities (Milan, Copenhagen, Dublin, Athens and Nicosia) were carried out. These campaigns covered weekly winter and summer concentration measurements in two (2) public buildings and two (2) private houses in each city. BTEX, terpenes, and carbonyls were measured using passive sampling in two sites inside the building and one outside. VOC emission measurements on selected building material have also been performed using Field and Laboratory Emission Cell (FLEC). The results on indoor concentrations for compounds such as formaldehyde (1.2-62.6 μg m -3), acetaldehyde (0.7-41.6 μg m -3), toluene (0.9-163.5 μg m -3), xylenes (0.2-177.5 μg m -3) and acetone (2.8-308.8 μg m -3) have shown diversity and relatively significant indoor sources depending on the building type, age etc. Indoor concentrations of these substances are varied depending on the building age and type. The percentage of approximately 40% of the indoor air quality levels originated from building materials.

  18. Novel method of measurement of radon exhalation from building materials.

    Science.gov (United States)

    Awhida, A; Ujić, P; Vukanac, I; Đurašević, M; Kandić, A; Čeliković, I; Lončar, B; Kolarž, P

    2016-11-01

    In the era of the energy saving policy (i.e. more air tight doors and windows), the radon exhaled from building materials tends to increase its concentration in indoor air, which increases the importance of the measurement of radon exhalation from building materials. This manuscript presents a novel method of the radon exhalation measurement using only a HPGe detector or any other gamma spectrometer. Comparing it with the already used methods of radon exhalation measurements, this method provides the measurement of the emanation coefficient, the radon diffusion length and the radon exhalation rate, all within the same measurement, which additionally defines material's radon protective properties. Furthermore it does not necessitate additional equipment for radon or radon exhalation measurement, which simplifies measurement technique, and thus potentially facilitates introduction of legal obligation for radon exhalation determination in building materials. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. BUILDING MATERIALS AND PRODUCTS BASED ON SILICON MANGANESE SLAGS

    Directory of Open Access Journals (Sweden)

    BOLSHAKOV V. I.

    2016-05-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-09-15

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

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

    National Research Council Canada - National Science Library

    Matavulj Milan; Molitoris Hans Peter

    2009-01-01

    .... 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...

  2. 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

  3. Radon exhalation from building materials used in Libya

    Science.gov (United States)

    Saad, A. F.; Al-Awami, Hend H.; Hussein, N. A.

    2014-08-01

    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.

  4. 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.

  5. 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).

  6. Using thermal power plants waste for building materials

    Science.gov (United States)

    Feduik, R. S.; Smoliakov, A. K.; Timokhin, R. A.; Batarshin, V. O.; Yevdokimova, Yu G.

    2017-10-01

    The recycled use of thermal power plants (TPPs) wastes in the building materials production is formulated. The possibility of using of TPPs fly ash as part of the cement composite binder for concrete is assessed. The results of X-ray diffraction and differential thermal analysis as well as and materials photomicrographs are presented. It was revealed that the fly ash of TPPs of Russian Primorsky Krai is suitable for use as a filler in cement binding based on its chemical composition.

  7. 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.

  8. Measurement of radon exhalation rate in various building materials ...

    Indian Academy of Sciences (India)

    mended by Organization for Economic Coopera- tion and Development (OECD 1979). Hence, the result shows that this study area is safe as far as the health hazards of radium are concerned. It is recommended that the radon exhalation rate should be measured for all building materials and a standard code placed on all ...

  9. Radon exhalation studies in building materials using solid-state ...

    Indian Academy of Sciences (India)

    Inhalation of 222Rn and its daughter products, especially 218Po and 214Po attached to aerosols present in ambient air, causes significant radiological hazard to human lungs. Radon appears mainly by diffusion processes from the point of origin, following a-decay of 226Ra in underground soil and building materials used.

  10. Salinization effects on the water sorption of porous building materials

    NARCIS (Netherlands)

    Brocken, H.J.P.; Rook, W.; Adan, O.C.G.

    1999-01-01

    The interaction of salt transport and moisture transport plays a crucial role in some deterioration mechanisms of porous building materials. For this reason it has been an important research subject for mant' years. Yet most research was still complicated by the lack of experimental techniques

  11. TECHNICAL BASIS FOR A CANDIDATE BUILDING MATERIALS RADIUM STANDARD

    Science.gov (United States)

    The report summarizes the technical basis for a candidate building materials radium standard. It contains the standard and a summary of the technical basis for the standard. (NOTE: The Florida Radon Research Program (FRRP), sponsored by the Environmental Protection Agency and the...

  12. 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}).

  13. Materials, used in historical buildings, analysis methods and solutions puroposals

    Science.gov (United States)

    Döndüren, M. Sami; Sişik, Ozlem

    2017-10-01

    Most of historical buildings are built with pressure principle and have the characteristics of masonry structures. Therefore, the structure components of buildings are constituted bearing walls, columns, buttresses, vaults and domes. Natural stone, cut stone, rubble stone brick or alternate materials were used in the bearing elements. Brick-dust and mortar with more binding feature were used as combination elements. In time, some problems were occurred in used materials and in structure as a result of various effects. Therefore, it is necessary to apply various applications in framework of repair and strengthening of buildings. In this study, restoration of historic buildings and the control of the adequacy of the bearing systems as one most important part of structure were examined. For this purpose, static analysis of Edirne-Merkez Demirtaş (Timurtaş) mosque located in Edirne was tested. Testes could give suggestions and be applied if buildings needed be revealed. The structure was modelled with finite element model of sap2000 package program and the forces generated under various loads and stresses, the occurred deformation due to that, overflow of allowable stress of this deformation and stresses were investigated. As the results of this study can be note that the maximum compressive stress at the construction is calculated as 1.1 MPa.

  14. Improve isolation materials and recommendation of residential buildings in Kazakhstan

    Science.gov (United States)

    Kim, Yuliya; Sun, Cheng; Nuguzhinov, Zhmagul

    2017-04-01

    The article shows the problem of high volumes of energy use in Kazakhstan and introduction of energy-efficient technologies, production and causes of the problem. To improve the thermal comfort, needed primarily to improve the thermal insulation properties of materials. This article examines the characteristics of thermal insulation materials and their application in the construction process in Kazakhstan. The material properties are calculated and shown as formulas, which can use in the future in the design of residential buildings. The construction studied of passive technology in the residential area. By the design process and the combination of design variables selected option.

  15. Method for modeling the gradual physical degradation of a porous material

    Energy Technology Data Exchange (ETDEWEB)

    Flach, Greg [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-09-20

    Cementitious and other engineered porous materials encountered in waste disposals may degrade over time due to one or more mechanisms. Physical degradation may take the form of cracking (fracturing) and/or altered (e.g. increased) porosity, depending on the material and underlying degradation mechanism. In most cases, the hydraulic properties of degrading materials are expected to evolve due to physical changes occurring over roughly the pore to decimeter scale, which is conducive to calculating equivalent or effective material properties. The exact morphology of a degrading material in its end-state may or may not be known. In the latter case, the fully-degraded condition can be assumed to be similar to a more-permeable material in the surrounding environment, such as backfill soil. Then the fully-degraded waste form or barrier material is hydraulically neutral with respect to its surroundings, constituting neither a barrier to nor conduit for moisture flow and solute transport. Unless the degradation mechanism is abrupt, a gradual transition between the intact initial and fully-degraded final states is desired. Linear interpolation through time is one method for smoothly blending hydraulic properties between those of an intact matrix and those of a soil or other surrogate for the end-state.

  16. 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}).

  17. 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

  18. 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.

  19. Spectral Signatures of Surface Materials in Pig Buildings

    DEFF Research Database (Denmark)

    Zhang, GuoQiang; Strøm, Jan; Blanke, Mogens

    2006-01-01

    in the investigation. Reflectance data were sampled under controlled lighting conditions using a spectrometer communicating with a portable computer. The measurements were performed in a laboratory with materials used in a pig house for 4-5 weeks. The spectral data were collected for the surfaces before, during......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....... In this study, the optical properties of different types of surfaces to be cleaned and the dirt found in finishing pig units were investigated in the visual and the near infrared (VIS-NIR) optical range. Four types of commonly used materials in pig buildings, i.e. concrete, plastic, wood and steel were applied...

  20. Valorisation of phosphogypsum as building material: Radiological aspects

    Directory of Open Access Journals (Sweden)

    Tayibi, H.

    2011-12-01

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

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

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

    Science.gov (United States)

    Tufan, M Çagatay; Disci, Tugba

    2013-01-01

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

  2. Ozone reactions with indoor materials during building disinfection

    DEFF Research Database (Denmark)

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

    2007-01-01

    There is scant information related to heterogeneous indoor chemistry at ozone concentrations necessary for the effective disinfection of buildings, i.e., hundreds to thousands of ppm. In the present study, 24 materials were exposed for 16 h to ozone concentrations of 1000-1200ppm in the inlet...... streams of test chambers. Initial ozone deposition velocities were similar to those reported in the published literature for much lower ozone concentrations, but decayed rapidly as reaction sites on material surfaces were consumed. For every material, deposition velocities converged to a relatively...... 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...

  3. Boosting LPMO-driven lignocellulose degradation by polyphenol oxidase-activated lignin building blocks

    OpenAIRE

    Frommhagen, Matthias; Mutte, Sumanth Kumar; Westphal, Adrie H.; Koetsier, Martijn J; Hinz, Sandra W A; Visser, Jaap; Vincken, Jean Paul; Weijers, Dolf; Berkel, van, T.J.C.; Gruppen, Harry; Kabel, Mirjam A.

    2017-01-01

    Background Many fungi boost the deconstruction of lignocellulosic plant biomass via oxidation using lytic polysaccharide monooxygenases (LPMOs). The application of LPMOs is expected to contribute to ecologically friendly conversion of biomass into fuels and chemicals. Moreover, applications of LPMO-modified cellulose-based products may be envisaged within the food or material industry. Results Here, we show an up to 75-fold improvement in LPMO-driven cellulose degradation using polyphenol oxi...

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

    Directory of Open Access Journals (Sweden)

    Dana Adamcová

    2016-09-01

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

  5. 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

    2015-10-01

    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.

  6. Luminescence dosimetry using building materials and personal objects.

    Science.gov (United States)

    Göksu, H Y; Bailiff, I K

    2006-01-01

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

  7. Perspectives of flax processing wastes in building materials production

    Science.gov (United States)

    Smirnova, Olga

    2017-01-01

    The paper discusses the possibility of using the flax boons for thermal insulation materials. The solution for systematization of materials based on flax boon is suggested. It based on the principle of building materials production using the flax waste with different types of binders. The purpose of the research is to obtain heat-insulating materials with different structure based on agricultural production waste - flax boon, mineral and organic binders. The composition and properties of organic filler - flax boons - are defined using infrared spectroscopy and standard techniques. Using the method of multivariate analysis the optimal ratio of flax boons and binders in production of pressed, porous and granular materials are determined. The effect of particles size distribution of flax boons on the strength of samples with the different composition is studied. As a result, the optimized compositions of pressed, porous and granular materials based on flax boons are obtained. Data on the physical and mechanical properties of these materials are given in the paper.

  8. Hygrothermal Material Properties for Soils in Building Science

    Energy Technology Data Exchange (ETDEWEB)

    Kehrer, Manfred [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Pallin, Simon B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-01-01

    Hygrothermal performance of soils coupled to buildings is complicated because of the dearth of information on soil properties. However they are important when numerical simulation of coupled heat and moisture transport for below-grade building components are performed as their temperature and moisture content has an influence on the durability of the below-grade building component. Soils can be classified by soil texture. According to the Unified Soil Classification System (USCA), 12 different soils can be defined on the basis of three soil components: clay, sand, and silt. This study shows how existing material properties for typical American soils can be transferred and used for the calculation of the coupled heat and moisture transport of building components in contact with soil. Furthermore a thermal validation with field measurements under known boundary conditions is part of this study, too. Field measurements for soil temperature and moisture content for two specified soils are carried out right now under known boundary conditions. As these field measurements are not finished yet, the full hygrothermal validation is still missing

  9. Research of the biodegradability of degradable/biodegradable plastic material in various types of environments

    OpenAIRE

    Dana Adamcová; Maja Radziemska; Joanna Fronczyk; Jan Zloch; Vaverková, Magdalena D.

    2017-01-01

    Research was carried out in order to assess biodegradability of degradable/biodegradable materials made of HDPE and mixed with totally degradable plastic additive (TDPA additive) or made of polyethylene (PE) with the addition of pro-oxidant additive (d2w additive), advertised as 100% degradable or certifi ed as compostable within various types of environments. Research conditions were: (i) controlled composting environment – laboratory-scale, (ii) real composting conditions – domestic compost...

  10. Stone Dust Agglomeration for Utilizing as Building Material

    Directory of Open Access Journals (Sweden)

    Gabriel Borowski

    2017-12-01

    Full Text Available In the paper we discuss the possibility of using stone dust for utilizing as building material. The tested material was amphibolite, found in the Sudeten Mountains and the Tatra Mountains in Poland. The chemical composition of dust was determined by means of spectrometry methods. Moreover, the basic physical properties of the material were designated. Stone dust was mixed with starch or cement binder. The binder addition was from 5% to 20% by weight. The water content was adjusted to about 25% humidity. The mixture was then compressed in a hydraulic press at 50 MPa. The results of the mechanical toughness of agglomerates were shown. On the basis of the results, acceptable toughness of agglomerates was found, with the addition of cement in mass share 20% and seasoning for 48 hours. However, starch was not suitable as a binder for agglomeration of amphibolite.

  11. Water sorption and solubility of core build-up materials.

    Science.gov (United States)

    Zankuli, M A; Devlin, H; Silikas, N

    2014-12-01

    To investigate the variation in water sorption and solubility across a range of different core build-up materials. Five materials were tested, four of which are resin-based materials (Grandio Core, Core.X Flow, Bright Flow Core, Speedee) and one resin-modified glass ionomer (Fuji II LC). All specimens (n=10) were immersed in 10ml distilled water in individual glass containers and weighed at one week, 14 and 28 days. After a total immersion time of 28 days, 7 specimens were dried to a constant mass, in a desiccator for 28 days. Three samples of each material were not dried, but were left in distilled water for 1 year, to determine the long-term water sorption properties. Specimens were weighed at monthly intervals until 6 months and then at the 9th and 12th months. Each specimen was measured using a digital electronic caliper (Mitutoyo Corporation, Japan). After 28 days immersion, the change in water sorption and solubility of the materials ranged from 12.9 to 67.1μg/mm(3) (P<0.001) and 0.9-6.4μg/mm(3) respectively (P<0.001). Except for Fuji II LC, an independent T-test showed significantly higher water sorption and solubility for the other materials after 1-year total immersion in water compared to 1 month (P<0.05). Using repeated measures ANOVA, all materials showed mass changes over time (1 month) (P<0.001). Grandio Core had the lowest water sorption and solubility among the tested materials. According to the ISO 4049 standards, all the tested materials showed acceptable water sorption and solubility, apart from the water sorption behavior of Fuji II LC. Copyright © 2014 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  12. 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

  13. Estimation of material degradation of VVER-1000 baffle

    Science.gov (United States)

    Harutyunyan, Davit; Koš'ál, Michal; Vandlík, Stanislav; Hojná, Anna; Schulc, Martin; Flibor, Stanislav

    2017-09-01

    The planned lifetime of the first commercial VVER-1000 units were designed for 30 to 35 years. Most of the early VVER plants are now reaching and/or passing the 35-year mark. Service life extension for another 10 to 30 years is now under investigation. Life extension requires the evaluation of pressure vessel internals degradation under long-term irradiation. One of the possible limiting factors for the service life of VVERs is a void swelling of the Russian type titanium stabilized stainless 08Ch18N10T steel used to construct the baffle surrounding the core. This article aims to show first steps towards deeper analysis of the baffle degradation process and to demonstrate the possibilities of precise calculation and measurements on the VVER-1000 mock-up in LR-0 reactor.

  14. Estimation of material degradation of VVER-1000 baffle

    Directory of Open Access Journals (Sweden)

    Harutyunyan Davit

    2017-01-01

    Full Text Available The planned lifetime of the first commercial VVER-1000 units were designed for 30 to 35 years. Most of the early VVER plants are now reaching and/or passing the 35-year mark. Service life extension for another 10 to 30 years is now under investigation. Life extension requires the evaluation of pressure vessel internals degradation under long-term irradiation. One of the possible limiting factors for the service life of VVERs is a void swelling of the Russian type titanium stabilized stainless 08Ch18N10T steel used to construct the baffle surrounding the core. This article aims to show first steps towards deeper analysis of the baffle degradation process and to demonstrate the possibilities of precise calculation and measurements on the VVER-1000 mock-up in LR-0 reactor.

  15. 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)

  16. 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.

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

    DEFF Research Database (Denmark)

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

    2015-01-01

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

  18. 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......, and no toxin production was detected from any of the five isolates of Pen. chrysogenum. Both isolates of Pen. polonicum produced 3-methoxy-viridicatin, verrucosidin, and verrucofortine. Two of five isolates of Pen. brevicompactum produced mycophenolic acid. From five out of six isolates of Alternaria spp...

  19. 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.

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

    CERN Document Server

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

    2005-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, Paul F. (Golden, CO); Maness, Pin-Ching (Golden, CO)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, P.F.; Pinching Maness.

    1993-10-05

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

  3. 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.

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

    Science.gov (United States)

    Boulet, Pascal; Brissinger, Damien; Collin, Anthony; Acem, Zoubir; Parent, Gilles

    2015-08-21

    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. 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

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

    Science.gov (United States)

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

    2012-03-20

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

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

    Science.gov (United States)

    Memon, Shazim Ali; Liao, Wenyu; Yang, Shuqing; Cui, Hongzhi; Shah, Syed Farasat Ali

    2015-02-05

    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.

  8. 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.

  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. ASSESSMENT OF EFFICIENCY OF APPLICATION OF A NEW BUILDING MATERIAL

    Directory of Open Access Journals (Sweden)

    Gumba Huta Msuratovich

    2012-10-01

    Full Text Available Methodical approaches and procedures of implementation of official provisions of Methodical Recommendations are considered in article. Upon completion of analysis of a number of factors, the authors suggest using the option of assessment of efficiency of application of a new construction material through the application of Methodical Recommendations for Assessment of Efficiency of Investment Projects. As for the assimilation of new materials by building companies engaged in construction operations, the recommendation is to assess the business project efficiency upon introduction of each new construction material, and capital investments are the main indicators of efficiency of construction materials, let alone net discounted profit and the payback period. Upon consideration of a number of conditions that underlie the mathematical and economic model that substantiates decision-making in terms of implementation of innovative projects, the project efficiency can be assessed on the basis of an integrated indicator - maximal return on capital investments. The proposed model also takes account of the payback period, although the efficiency of new construction materials does not take account of any positive social effect of their introduction.

  11. Self-Organized Construction with Continuous Building Material

    DEFF Research Database (Denmark)

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

    2016-01-01

    Self-organized construction with continuous, structured building material, as opposed to modular units, offers new challenges to the robot-based construction process and lends the opportunity for increased flexibility in constructed artifact properties, such as shape and deformation. As an example...... investigation, we look at continuous filaments organized into braided structures, within the context of bio-hybrids constructing architectural artifacts. We report the result of an early swarm robot experiment. The robots successfully constructed a braid in a self-organized process. The construction process can...... be extended by using different materials and by embedding sensors during the self-organized construction directly into the braided structure. In future work, we plan to apply dedicated braiding robot hardware and to construct sophisticated 3-d structures with local variability in patterns of filament...

  12. Building Blocks Incorporating Waste Materials Bound with Bitumen

    Directory of Open Access Journals (Sweden)

    Thanaya I.N.A.

    2010-01-01

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

  13. REQUIREMENTS FOR DRILLING CUTTINGS AND EARTH-BASED BUILDING MATERIALS

    Directory of Open Access Journals (Sweden)

    Chertes Konstantin L'vovich

    2017-08-01

    Full Text Available In this article, the problem of utilization of drilling cuttings by means of scavenging, is researched. The product received could be used for the restoration of lands disturbed during construction and economic activities. When assessing technogenic formations, the binary approach was used, as a system of two components. The purpose of the study is to assess the state and possibility of utilizing drilling cuttings as raw materials in order to produce technogenic building materials; to study the effect of the degree of homogeneity of initial mixtures based on drilling cuttings, on kinetics of their hardening which leads to obtaining final products for various applications . As a result of research, relations of hardening and subsequent strengthening of slurry-cement mixtures were obtained; the plan of the process area for treatment of drilling cuttings is presented on the spot of demolished drilling pit.

  14. The physics of degradation in engineered materials and devices fundamentals and principles

    CERN Document Server

    Swingler, Jonathan

    2015-01-01

    Degradation is apparent in all things and is fundamental to both manufactured and natural objects. It is often described by the second law of thermodynamics, where entropy, a measure of disorder, tends to increase with time in a closed system. Things age! This concise reference work brings together experts and key players engaged in the physics of degradation to present the background science, current thinking and developments in understanding, and gives a detailed account of emerging issues across a selection of engineering applications. The work has been put together to equip the upper level undergraduate student, postgraduate student, as well as the professional engineer and scientist, in the importance of physics of degradation. The aim of The Physics of Degradation in Engineered Materials and Devices is to bridge the gap between published textbooks on the fundamental science of degradation phenomena and published research on the engineering science of actual fabricated materials and devices. A history o...

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

    Science.gov (United States)

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

    2010-01-01

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

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

    Science.gov (United States)

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

    2014-12-01

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

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

    Science.gov (United States)

    Gu, Hannian; Wang, Ning; Liu, Shirong

    2012-09-01

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

  18. Injectable degradable composite materials for bone repair and drug delivery

    OpenAIRE

    Zhao, X.

    2010-01-01

    The aim of this project was to develop injectable materials to repair damaged bone and, to simultaneously release antibacterial drugs and genes in a controllable manner. Fluid poly (propylene glycol -co- lactide) dimethacrylate (PGLA-DMA) was first synthesised and then filled with varying levels of β- tricalcium phosphate (β-TCP) and monocalcium phosphate monohydrate (MCPM) to fabricate composite materials. For all formulations (including polymer and composites), full methac...

  19. Environmental Degradation of Fuels, Fluids and Related Materials for Aircraft

    Science.gov (United States)

    1976-03-01

    but, rather, a hydrogen bonded carbonyl possibly due to a primary amide or carboxylic acid. 35 \\- -~ -~ - - -’ ’ ~ ~ -° i l 2. Conclusions A polyester ...is not a part of the original fuel, but is probably a contaminant. Its source may be a bottle cap seal (or its adhesive) or extractable material from a...bis-phenol A. The compound is commonly used in the preparation of poly- carbonate and epoxy resins . It is not a natural material and would not

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

    Science.gov (United States)

    Verker, Ronen; Grossman, Eitan; Gouzman, Irina

    2011-02-01

    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.

  1. Cementitious building material incorporating end-capped polyethylene glycol as a phase change material

    Science.gov (United States)

    Salyer, Ival O.; Griffen, Charles W.

    1986-01-01

    A cementitious composition comprising a cementitious material and polyethylene glycol or end-capped polyethylene glycol as a phase change material, said polyethylene glycol and said end-capped polyethylene glycol having a molecular weight greater than about 400 and a heat of fusion greater than about 30 cal/g; the compositions are useful in making pre-formed building materials such as concrete blocks, brick, dry wall and the like or in making poured structures such as walls or floor pads; the glycols can be encapsulated to reduce their tendency to retard set.

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

    Directory of Open Access Journals (Sweden)

    N. I. Berezovsky

    2014-01-01

    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.

  3. Prediction of Long Term Degradation of Insulating Materials

    Science.gov (United States)

    2015-05-01

    are hydrophobic (Aspen Aerogels 2011, Acoustiblok Inc. 2009, Cabot Corp. 2013). Table 2-2 lists the properties of the aerogel materials. Figure 2-5...common/userfiles/file/Data%20Sheets/Spaceloft_MSDS .pdf Cabot Corp. 2013. Aerogel Thermal Wrap. Safety Data Sheet, http://www.google.com/url?sa=t&rct

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

    Directory of Open Access Journals (Sweden)

    Lerma, C.

    2014-03-01

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

  5. Increase in buildings sustainability by using renewable materials and energy

    Energy Technology Data Exchange (ETDEWEB)

    Milutiene, Edita [Kaunas University of Technology, Institute of Environmental Engineering, Kaunas (Lithuania); Lithuanian Solar Energy Association, Kaunas (Lithuania); Straw Houses Builders' Association, Kaunas (Lithuania); Staniskis, Jurgis K. [Kaunas University of Technology, Institute of Environmental Engineering, Kaunas (Lithuania); Krucius, Audrys [Straw Houses Builders' Association, Kaunas (Lithuania); JSK ' ' Ecococon' ' , Kaunas (Lithuania); Auguliene, Vida [Lithuanian Hydrometeorological Service under the Ministry of Environment of the Republic of Lithuania, Kaunas (Lithuania); Ardickas, Daumilas [University of Cambridge, Girton College, Cambridge (United Kingdom)

    2012-12-15

    Sustainable development could be seen as indispensable condition for survival of civilization. Construction sector is a field with immediate need for reducing environmental impacts. Sustainability measures applied for buildings could produce very efficient results to the people. The paper provides the methods of construction sustainability increase by researching, developing, and applying the technologies which use renewable materials and energy. The paper analyzes the cases of both a solar eco house which was built of original prefabricated straw-bale panels and was designed to use direct solar energy; and an educational project promoting straw-bale construction and seeking to mitigate climate change. The project results have shown the need of spreading information on sustainable building methods to be accepted by wider society and to be applied to the construction industry. Monitoring of solar ecohouse has proved that direct solar energy gains are significant in reducing heating degree-days in 55 N latitude and in allowing to save half the energy needed for heating. (orig.)

  6. Acquisition System Verification for Energy Efficiency Analysis of Building Materials

    Directory of Open Access Journals (Sweden)

    Natalia Cid

    2017-08-01

    Full Text Available Climate change and fossil fuel depletion foster interest in improving energy efficiency in buildings. There are different methods to achieve improved efficiency; one of them is the use of additives, such as phase change materials (PCMs. To prove this method’s effectiveness, a building’s behaviour should be monitored and analysed. This paper describes an acquisition system developed for monitoring buildings based on Supervisory Control and Data Acquisition (SCADA and with a 1-wire bus network as the communication system. The system is empirically tested to prove that it works properly. With this purpose, two experimental cubicles are made of self-compacting concrete panels, one of which has a PCM as an additive to improve its energy storage properties. Both cubicles have the same dimensions and orientation, and they are separated by six feet to avoid shadows. The behaviour of the PCM was observed with the acquisition system, achieving results that illustrate the differences between the cubicles directly related to the PCM’s characteristics. Data collection devices included in the system were temperature sensors, some of which were embedded in the walls, as well as humidity sensors, heat flux density sensors, a weather station and energy counters. The analysis of the results shows agreement with previous studies of PCM addition; therefore, the acquisition system is suitable for this application.

  7. Identification of the capillary transfer coefficient in porous building materials

    Science.gov (United States)

    Vala, J.; Jarošová, P.

    2013-10-01

    Physical description of the capillary transfer of water (or other liquids) in porous building material comes out from the thermomechanical principle of mass balance and from the Fick law, nonlinear only in the multiplicative capillary transfer coefficient. However, such seemingly simple formulation leads to the non-trivial theory of solvability and convergence of sequences of approximate solutions even for direct problems. The analysis of inverse problems relies on various simplified approaches, whose mutual relations, including those to the related direct problems, are not very transparent: some additional least squares, regression, etc. tricks are often hidden in computational algorithms. This paper demonstrates the general formulation, containing most identification approaches used in practice as certain special cases, both those using the 3-dimensional integration and those relying on (semi-)analytical formulae relying on the very special geometrical configurations. An illustrative example shows the possibility of implementation of the sketched algorithms in the MATLAB environment.

  8. Determination of fungal spore release from wet building materials

    DEFF Research Database (Denmark)

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

    2003-01-01

    of fungal spores was induced by well-defined jets of air impacting from rotating nozzles. The spores and other particles released from the surface were transported by the air flowing from the chamber through a top outlet to a particle counter and sizer. For two of the fungi (Penicillium chrysogenum...... isolate, whereas the spore release is very different for different fungi under identical conditions. Also, the relationship between air velocity and spore release depends on the fungus. For some fungi a significant number of particles smaller than the spore size were released. The method applied......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...

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

    Science.gov (United States)

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

    2015-06-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2004-07-01

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

  11. Synthesis, properties and biomedical applications of hydrolytically degradable materials based on aliphatic polyesters and polycarbonates.

    Science.gov (United States)

    Brannigan, Ruairí P; Dove, Andrew P

    2016-12-20

    Polyester-based polymers represent excellent candidates in synthetic biodegradable and bioabsorbable materials for medical applications owing to their tailorable properties. The use of synthetic polyesters as biomaterials offers a unique control of morphology, mechanical properties and degradation profile through monomer selection, polymer composition (i.e. copolymer vs. homopolymer, stereocomplexation etc.) and molecular weight. Within this review, the synthetic routes, degradation modes and application of aliphatic polyester- and polycarbonate-based biomaterials are discussed.

  12. Detection of asbestos fibres in selected building materials

    Directory of Open Access Journals (Sweden)

    Jiří Škvarla

    2009-09-01

    Full Text Available Asbestos is a naturally occurring mineral having a fibrous structure. The Directive 2003/18/EC of the European Parliamentand of the Council of 27 March 2003 considers „asbestos“ the following fibrous silicates: actinolite, gruenerite (amosite, anthophyllite,chrysotile, crocidolite, tremolite.Materials based on asbestos fibres and other mineral fibres have preferential characteristics; they are chemically, electricallyand thermally resistant. Because of these unique characteristics, asbestos is utilized by builders, mainly in roofing, insulation materialsand facades.In connection with the restriction of the usage of asbestos fibres usage in EU is due to the documented carcinogenic impact,it is necessary to detect and identify these fibres.Selected samples of building insulation materials were studied by the polarized light microscopy and by the scanning electronmicroscopy. For the purpose of measuring asbestos, only fibres with a length of more than five micrometers, a breadth of less than threemicrometers and a length/breadth ratio greater than 3:1 were taken into consideration. Asbestos fibres, fibres of mineral wooland cellulose we identified.

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

    Science.gov (United States)

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

    2016-11-01

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

  14. Applications of environmental data and declarations for building materials

    DEFF Research Database (Denmark)

    In December 1997 the building research institutes in Norway, Sweden, Finland and Denmark arranged a workshop with the purpose of discussing examples from applications of environmental data. The participants were researchers, producers and building authorities. The report includes contributions...

  15. Introduction to nano- and biotech-based materials for energy building efficiency

    OpenAIRE

    Torgal,Fernando Pacheco

    2016-01-01

    This chapter starts with an overview of the unsustainable energy consumption which is due to fast population growth and related greenhouse gas emissions. The case of energy efficiency building is introduced. A short analysis of the ambitious European nearly zero-energy building (NZEB) target is presented. Shortcomings of current materials concerning energy building efficiency are reviewed. Examples of promising nano- and biotech-based materials for energy building efficiency are briefly cover...

  16. Advanced FRP for flooring in buildings: a low carbon material application in the construction industry

    OpenAIRE

    Gao, Yijian

    2013-01-01

    Fibre-reinforced polymers (FRP) are building materials that permit both the improvement of long-term building performance and the simplification of the construction process, thanks to their high specific strength, low thermal conductivity, good environmental resistance, and ability to be formed into complex shapes. FRP materials are well-suited to fulfilling many building functions. By integrating traditionally separate building systems and layers into single function-integrated components, a...

  17. Wood and Other Materials Used to Construct Nonresidential Buildings - Canada

    Science.gov (United States)

    David B. McKeever; Joe Elling

    2014-01-01

    Low-rise nonresidential building construction is an important market in Canada for lumber, engineered wood products, structural wood panels, and nonstructural wood panels. This report examines wood products consumption in 2012 for construction of selected low-rise nonresidential buildings types that have six or fewer stories. Buildings with more than six stories are...

  18. A REVIEW OF COMPARATIVE EVALUATION OF THERMAL INSULATION MATERIALS FOR BUILDING WALL APPLICATIONS

    OpenAIRE

    Dr. RK. Jain *, Chouhan Balaji, Dhananjay Singh

    2016-01-01

    Attention towards the thermal performance of building materials, particularly thermal insulation systems for buildings, has grown in recent years. Thermal insulation of building walls has a significant effect on the reduction of thermal energy consumption in buildings Making a thermal insulation of a building external wall can in terms of economic aspects be approached as an investment. In this investment the cost is related to the purchase, transport and laying the insulation, whereas the pr...

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

    Directory of Open Access Journals (Sweden)

    Magdalena Vaverková

    2014-10-01

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

  20. Heat transfer characteristics of building walls using phase change material

    Science.gov (United States)

    Irsyad, M.; Pasek, A. D.; Indartono, Y. S.; Pratomo, A. W.

    2017-03-01

    Minimizing energy consumption in air conditioning system can be done with reducing the cooling load in a room. Heat from solar radiation which passes through the wall increases the cooling load. Utilization of phase change material on walls is expected to decrease the heat rate by storing energy when the phase change process takes place. The stored energy is released when the ambient temperature is low. Temperature differences at noon and evening can be utilized as discharging and charging cycles. This study examines the characteristics of heat transfer in walls using phase change material (PCM) in the form of encapsulation and using the sleeve as well. Heat transfer of bricks containing encapsulated PCM, tested the storage and released the heat on the walls of the building models were evaluated in this study. Experiments of heat transfer on brick consist of time that is needed for heat transfer and thermal conductivity test as well. Experiments were conducted on a wall coated by PCM which was exposed on a day and night cycle to analyze the heat storage and heat release. PCM used in these experiments was coconut oil. The measured parameter is the temperature at some points in the brick, walls and ambient temperature as well. The results showed that the use of encapsulation on an empty brick can increase the time for thermal heat transfer. Thermal conductivity values of a brick containing encapsulated PCM was lower than hollow bricks, where each value was 1.3 W/m.K and 1.6 W/m.K. While the process of heat absorption takes place from 7:00 am to 06:00 pm, and the release of heat runs from 10:00 pm to 7:00 am. The use of this PCM layer can reduce the surface temperature of the walls of an average of 2°C and slows the heat into the room.

  1. Triboelectric Nanogenerator Powered Electrochemical Degradation of Organic Pollutant Using Pt-Free Carbon Materials.

    Science.gov (United States)

    Gao, Shuyan; Chen, Ye; Su, Jingzhen; Wang, Miao; Wei, Xianjun; Jiang, Tao; Wang, Zhong Lin

    2017-04-25

    Carbon electrode materials are fabricated from bean curd to replace costly Pt-based electrodes to degrade methyl red (MR) as self-driven by a multilayer linkage triboelectric nanogenerator (ML-TENG). With the sponge as the buffer layer and precharge injection, the peak open-circuit voltage, Voc, short-circuit current, Isc, and maximum power density of the ML-TENG can reach and remain stable at 1300 V, 1.2 mA, and 7.4 W m-2 (load resistance = 500 KΩ), respectively. Using the electric power generated by such an updated TENG, highly toxic and carcinogenic MR can be indirectly degraded to CO2 through an oxidation process induced by active chlorine produced at the as-obtained carbon-based electrode interface. Such an electrochemical degradation mechanism is proposed based on the cyclic voltammogram, gas chromatograph-mass spectrometer, and mass spectrometer. With compelling features of the TENG and carbon materials, such as sustainable energy, high and stable output performance, cost savings, and high degradation efficiency, this work pioneers the marriage of the TENG with carbon-based materials to self-power electrochemical degradation of organic pollutants for environmental protection.

  2. Research of the biodegradability of degradable/biodegradable plastic material in various types of environments

    Directory of Open Access Journals (Sweden)

    Dana Adamcová

    2017-04-01

    Full Text Available Research was carried out in order to assess biodegradability of degradable/biodegradable materials made of HDPE and mixed with totally degradable plastic additive (TDPA additive or made of polyethylene (PE with the addition of pro-oxidant additive (d2w additive, advertised as 100% degradable or certifi ed as compostable within various types of environments. Research conditions were: (i controlled composting environment – laboratory-scale, (ii real composting conditions – domestic compost bin, (iii real composting conditions – industrial composting plant and (iv landfill conditions. The results demonstrate that the materials made of HDPE and mixed with totally degradable plastic additive (TDPA additive or made of polyethylene (PE with the addition of pro-oxidant additive (d2w additive or advertised as 100% degradable did not biodegrade in any of the above-described conditions and remained completely intact at the end of the tests. Biodegradation of the certified compostable plastic bags proceeded very well in laboratory-scale conditions and in real composting conditions – industrial composting plant, however, these materials did not biodegrade in real composting conditions – domestic compost bin and landfill conditions.

  3. 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)

  4. Degradation of sustainable mulch materials in two types of soil under laboratory conditions

    Science.gov (United States)

    Villena, Jaime; González, Sara; Moreno, Carmen; Aceituno, Patricia; Campos, Juan; Meco, Ramón; María Moreno, Marta

    2017-04-01

    Mulching is a technique used in cultivation worldwide, especially for vegetable crops, for reducing weed growth, minimising or eliminating soil erosion, and often for enhancing total yields. Manufactured plastic films, mainly polyethylene (PE), have been widely used for this purpose due to their excellent mechanical properties, light weight and relatively low prices in recent years. However, the use of PE is associated with serious environmental problems related to its petrochemical origin and its long shelf-life, which causes a waste problem in our crop fields. For this reason, the use of biodegradable mulch materials (biopolymers and papers) as alternative to PE is increasing nowadays, especially in organic farming. However, these materials can suffer an undesirable early degradation (and therefore not fulfilling their function successfully), greatly resulting from the type of soil. For this reason, this study aimed to analyse the degradation pattern of different mulch materials buried in two types of soils, clay and sand, under laboratory conditions (25°C, dark surroundings, constant humidity). The mulch materials used were: 1) black polyethylene (15 µm); black biopolymers (15 µm): 2) maize starch-based, 3) potato starch-based, 4) polylactic acid-based, 5) black paper, 85 g/m2. Periodically (every 15-20 days), the weight and surface loss of the different materials were recorded. The results indicate that mulch degradation was earlier and higher in the clay soil, especially in the paper and in the potato starch-based materials, followed by the maize starch-based mulch, while polylactic acid-based suffered the least and the latest degradation. Keywords: mulch, biodegradable, biopolymer, paper, degradation. Acknowledgements: the research was funded by Project RTA2011-00104-C04-03 from the INIA (Spanish Ministry of Economy and Competitiveness).

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

    Science.gov (United States)

    Dunlosky, John; Mueller, Michael L.

    2016-01-01

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

  6. Degradable hybrid materials based on cationic acylhydrazone dynamic covalent polymers promote DNA complexation through multivalent interactions.

    Science.gov (United States)

    Bouillon, Camille; Paolantoni, Delphine; Rote, Jennifer C; Bessin, Yannick; Peterson, Larryn W; Dumy, Pascal; Ulrich, Sébastien

    2014-11-03

    The design of smart nonviral vectors for gene delivery is of prime importance for the successful implementation of gene therapies. In particular, degradable analogues of macromolecules represent promising targets as they would combine the multivalent presentation of multiple binding units that is necessary for achieving effective complexation of therapeutic oligonucleotides with the controlled degradation of the vector that would in turn trigger drug release. Toward this end, we have designed and synthesized hybrid polyacylhydrazone-based dynamic materials that combine bis-functionalized cationic monomers with ethylene oxide containing monomers. Polymer formation was characterized by (1) H and DOSY NMR spectroscopy and was found to take place at high concentration, whereas macrocycles were predominantly formed at low concentration. HPLC monitoring of solutions of these materials in aqueous buffers at pH values ranging from 5.0 to 7.0 revealed their acid-catalyzed degradation. An ethidium bromide displacement assay and gel electrophoresis clearly demonstrated that, despite being dynamic, these materials are capable of effectively complexing dsDNA in aqueous buffer and biological serum at N/P ratios comparable to polyethyleneimine polymers. The self-assembly of dynamic covalent polymers through the incorporation of a reversible covalent bond within their main chain is therefore a promising strategy for generating degradable materials that are capable of establishing multivalent interactions and effectively complexing dsDNA in biological media. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. 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.

  8. Digital Learning Material for Model Building in Molecular Biology

    Science.gov (United States)

    Aegerter-Wilmsen, Tinri; Janssen, Fred; Hartog, Rob; Bisseling, Ton

    2005-01-01

    Building models to describe processes forms an essential part of molecular biology research. However, in molecular biology curricula little attention is generally being paid to the development of this skill. In order to provide students the opportunity to improve their model building skills, we decided to develop a number of digital cases about…

  9. 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) =elements. Determination of specific activity of natural radioactive nuclei. Interstate Standard. 4. Krisiuk E.M. et al., (1971). A study on Radioactivity in Building Materials (Leningrad: Research Institute for radiation Hygiene) 5. Beretka, J., & Mathew, P. J. (1985). Natural radioactivity of Australian building materials, waste and by-products. 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

  10. 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.

  11. Thorium and Uranium in the Rock Raw Materials Used For the Production of Building Materials

    Science.gov (United States)

    Pękala, Agnieszka

    2017-10-01

    Thorium and uranium are constant components of all soils and most minerals thereby rock raw materials. They belong to the particularly dangerous elements because of their natural radioactivity. Evaluation of the content of the radioactive elements in the rock raw materials seems to be necessary in the early stage of the raw material evaluation. The rock formations operated from deposits often are accumulated in landfills and slag heaps where the concentration of the radioactive elements can be many times higher than under natural conditions. In addition, this phenomenon may refer to buildings where rock raw materials are often the main components of the construction materials. The global control system of construction products draws particular attention to the elimination of used construction products containing excessive quantities of the natural radioactive elements. In the presented study were determined the content of thorium and uranium in rock raw materials coming from the Bełachatów lignite deposit. The Bełchatów lignite deposit extracts mainly lignite and secondary numerous accompanying minerals with the raw material importance. In the course of the field works within the framework of the carried out work has been tested 92 samples of rocks of varied petrographic composition. There were carried out analyses of the content of the radioactive elements for 50 samples of limestone of the Jurassic age, 18 samples of kaolinite clays, and 24 samples of siliceous raw materials, represented by opoka-rocks, diatomites, gaizes and clastic rocks. The measurement of content of the natural radioactive elements thorium and uranium based on measuring the frequency counts of gamma quantum, recorded separately in measuring channels. At the same time performed measurements on volume patterns radioactive: thorium and uranium. The studies were carried out in Mazar spectrometer on the powdered material. Standardly performed ten measuring cycles, after which were calculated

  12. Low Innovation among Building Material Suppliers: The Natural Level of the Trade

    Directory of Open Access Journals (Sweden)

    Jan Sundquist

    2012-11-01

    Full Text Available  Many studies concerning innovation have been carried out on building contractors, but very few have studied innovation among the suppliers of building materials. In Sweden the cost of building materials is approximately 40% of the total building costs. Some products also need more handeling than others, therefore not only cost but also productivity is affectedby the suppliers of building materials. This article focuses on innovation among building material suppliers which is found to be low. The suppliers are compared to other lines of business to show the level of their innovation processes. The article is based upon slightly over 800 companies of various sizes. Important findings are:A smaller proportion of the Building Material suppliers than of the Other Manufacturers offer new products, invest in R&D, machinery and marketing the introduction of products.The Building Material Suppliers have a greater proportion of their sales from older products and have older equipment than Other Manufacturers.The Building Material Suppliers have poorer production processes and they are not as good at finding new ides as the Other ManufacturersThe study reveals barriers within the trade, where motivation seems to be of great importance.

  13. 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.

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

    OpenAIRE

    Hussein J. Akeiber; Mazlan A. Wahid; Hussen, Hasanen M.; Abdulrahman Th. Mohammad

    2014-01-01

    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 accordi...

  15. The global warming potential of building materials : An application of life cycle analysis in Nepal

    NARCIS (Netherlands)

    Bhochhibhoya, Silu; Zanetti, Michela; Pierobon, Francesca; Gatto, Paola; Maskey, Ramesh Kumar; Cavalli, Raffaele

    2017-01-01

    This paper analyzes the global-warming potential of materials used to construct the walls of 3 building types - traditional, semimodern, and modern - in Sagarmatha National Park and Buffer Zone in Nepal, using the life-cycle assessment approach. Traditional buildings use local materials, mainly wood

  16. Literature review on use of nonwood plant fibers for building materials and panels

    Science.gov (United States)

    John A. Youngquist; Brent E. English; Roger C. Scharmer; Poo Chow; Steven R. Shook

    1994-01-01

    The research studies included in this review focus on the use of nonwood plant fibers for building materials and panels. Studies address (1) methods for efficiently producing building materials and panels from nonwood plant fibers; (2) treatment of fibers prior to board production; (3) process variables, such as press time and temperature, press pressure, and type of...

  17. 29 CFR 779.336 - Sales of building materials for commercial property construction.

    Science.gov (United States)

    2010-07-01

    ... property construction. Sales of building materials to a contractor or speculative builder for the... 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...

  18. Characterization of the environmental performance of the insulating materials in the enveloping of the building.

    OpenAIRE

    Carabaño Rodriguez, Rocio; Bedoya Frutos, Cesar

    2012-01-01

    Insulating materials in buildings are one of the main factors that should be taken into account when talking about sustainability since with a correct application it could imply important savings for the citizens. In the course of its life, a building requires a series of supplies to perform the duties it has been built for, generating an impact on the environment. The selection of one material or another will establish partly the global environmental impact of the building. Choosing the righ...

  19. Multi-analytical methodology to diagnose the environmental impact suffered by building materials in coastal areas.

    Science.gov (United States)

    Gómez-Laserna, Olivia; Cardiano, Paola; Diez-Garcia, Marta; Prieto-Taboada, Nagore; Kortazar, Leire; Olazabal, María Ángeles; Madariaga, Juan Manuel

    2018-02-01

    This work is focused on the development of an innovative multi-analytical methodology to estimate the impact suffered by building materials in coastal environments. With the aim of improving the in situ spectroscopic assessment, which is often based on XRF and Raman spectrometers, diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy was implemented in the diagnosis study. In this way, the additional benefits from DRIFT were compared to the usual in situ analyses of building materials, which often have interferences from fluorescence and reststrahlen effects. The studies were extended to the laboratory scale by μ-X-ray fluorescence (μ-XRF) cross-section mapping and ion chromatography (IC), and the IC quantitative data were employed to develop thermodynamic models using the ECOS-RUNSALT program, with the aim of rationalizing the behavior of soluble salts with variations in the temperature and the relative humidity (RH). The multi-analytical methodology allowed identification of the most significant weathering agents and classification of the severity of degradation according to the salt content. The suitability of a DRIFT portable device to analyze these types of matrices was verified. Although the Kramers-Kronig algorithm correction proved to be inadequate to decrease the expected spectral distortions, the assignment was successfully performed based on the secondary bands and intensification of the overtones and decreased the time needed for in situ data collection. In addition, the pollutants' distribution in the samples and the possible presence of dangerous compounds, which were not detected during the in situ analysis campaigns, provided valuable information to clarify weathering phenomena.

  20. Innovative approaches to organization and management of material streams of building complex

    Directory of Open Access Journals (Sweden)

    I.A. Arutyunyan

    2013-08-01

    Full Text Available Purpose. Development of theoretic and methodological approaches and scientific and practical recommendations concerning the management of the material flows of building complex. Methodology. Research includes analysis of existing scientific works concerning the problems of management of the construction development programs taking into account logistization on the enterprises of different branches related to the building complex. Experience generalization of administrative decision making in the process of production preparation, in particular the motion of material flows management of building resources and information flows (which accompany building resources, systematization of experience, logic analysis, design and system processing of information. Findings. Results give the building organization management an opportunity to estimate the material and technical support of the building objects according to the terms of building, technology of building processes, as well as to into account the minimization of expenses. Originality. Originality lies in the fact that the theoretical and methodological management foundations of the logistic system formation in the programs of building complex development are formulated on the basis of organization methodology development, planning and management from the point of view of the only system positions. Practical value. The contribution to the decision of the number of complex organizational and economic problems accompanied by the problems of building development is provided due to the increase of management efficiency of the material flows of building complex.

  1. The Global Warming Potential of Building Materials: An Application of Life Cycle Analysis in Nepal

    Directory of Open Access Journals (Sweden)

    Silu Bhochhibhoya

    2017-04-01

    Full Text Available This paper analyzes the global-warming potential of materials used to construct the walls of 3 building types—traditional, semimodern, and modern—in Sagarmatha National Park and Buffer Zone in Nepal, using the life-cycle assessment approach. Traditional buildings use local materials, mainly wood and stone, while semimodern and modern buildings use different amounts of commercial materials, such as cement and glass wool. A comparison of the greenhouse gas emissions associated with the 3 building types, using as the functional unit 1 m2 of wall, found that traditional buildings release about one-fourth of the greenhouse gas emissions released by semimodern buildings and less than one-fifth of the emissions of modern buildings. However, the use of thermal insulation in the modern building walls helps to reduce the energy consumption for space heating and consequently to reduce the global warming potential. In 25 years, the total global warming potential of a traditional building will be 20% higher than that of a modern building. If local materials, such as wood, are used in building construction, the emissions from production and transportation could be dramatically reduced.

  2. Energy efficiency in historic buildings : new materials for traditional envelopes

    OpenAIRE

    Hoffman, Monika

    2017-01-01

    ABSTRACT: The energy consumed by historical buildings is much higher comparing to the modern constructions. The law is mostly related with the newly built constructions, stating requirements and guidelines for the energy demand. However, regulating the law concerning historical buildings is very difficult because of the need for preserving the historical and cultural value they represent. Moreover, recently discovered technologies can support the transformation process providing the most effi...

  3. 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.

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

    NARCIS (Netherlands)

    Lelieveld, C.M.J.L.

    2013-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Yibo Ai

    2015-02-01

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

  6. Material degradation in implant-retained cobalt-chrome and titanium frameworks.

    Science.gov (United States)

    Hjalmarsson, L; Smedberg, J-I; Wennerberg, A

    2011-01-01

    The purpose of the study was to estimate in vitro material degradation in implants and cobalt-chrome or titanium frameworks, before and after exposure to artificial saliva. Four full-arch implant frameworks were fabricated according to the Cresco™ method (Astra Tech AB, Mölndal, Sweden), two in a cobalt-chrome alloy and two in commercially pure (CP) titanium. They were cut vertically, and the three central sections of each framework were used. Element leakage into an artificial saliva solution was observed with mass spectrometry. Before artificial saliva exposure, three Brånemark System(®) implants (Nobel Biocare AB, Gothenburg, Sweden) were screw-retained to cobalt-chrome sections, and three to titanium sections. The contact surfaces with the implants of the framework sections and the corresponding surfaces of six implants were examined with optical interferometry before and after exposure to artificial saliva to evaluate material degradation. Conventional descriptive statistics were used to present the mass spectrometry and interferometry data. One-way anova and Dunnett's T3 post hoc test were used to identify and study differences between the groups. To highlight changes within the groups, the Student's t-test was used. The significance level was set at 5%. There was significantly more leakage of cobalt elements than of titanium and chrome (P chrome frameworks, both before and after saliva exposure (P < 0·05). The findings in this study suggest active material degradation processes for both implants and framework materials. © 2010 Blackwell Publishing Ltd.

  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. Algae and their biodegradation effects on building materials in the Ostrava industrial agglomeration

    Science.gov (United States)

    Vojtková, H.

    2017-10-01

    Microorganisms cause changes in the building stone, which reduce its usable life and reliability. Microalgae make important parts of the biodegradation consortia of microorganisms on the surface of building materials. Via their metabolites, microalgae affect the stability of mineral components and thus lead to the material destruction. The aim of the paper was to identify aerophytic microalgae on the surface of engineering structures in the Ostrava agglomeration, and to describe the basic interactions between such microorganisms and the building materials, which may lead to the destruction of the materials.

  9. Degradation behavior of Ca-Mg-Zn intermetallic compounds for use as biodegradable implant materials.

    Science.gov (United States)

    Hagihara, Koji; Shakudo, Shuhei; Fujii, Kenta; Nakano, Takayoshi

    2014-11-01

    With the goal of developing new biodegradable implant materials, we have investigated the degradation behavior of (Ca, Mg)-based intermetallic compounds. The degradation behavior of the compounds within the Ca-Mg-Zn system was roughly classified into four groups, and their behaviors were strongly influenced by the compositions of the compounds. For example, the Ca3MgxZn(15-x) compound exhibited a large solubility region with varying the Mg/Zn ratio, and the Ca3Mg12Zn3 phase alloy with the lowest Zn content was rapidly broken apart within 6h of immersion. Alternatively, the Ca3Mg4.6Zn10.4 phase alloy with the highest Zn content retained the bulk shape even after 250 h of immersion. These varying degradation behaviors were ascribed to the difference in the formability of Zn oxide as a protective layer against corrosion on the specimen surfaces, depending on the Zn content. The gained results suggest that there is a feasibility on developing new biodegradable materials based on intermetallic compounds in which the degradation rate can be controlled by their compositions. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. 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

  11. Three-dimensional biomaterial degradation - Material choice, design and extrinsic factor considerations.

    Science.gov (United States)

    Yildirimer, Lara; Seifalian, Alexander M

    2014-01-01

    The apparent difficulty to precisely control fine-tuning of biomaterial degradation has initiated the recent paradigm shift from conventional top-down fabrication methods to more nature-inspired bottom-up assemblies. Sophistication of material fabrication techniques allows today's scientists to reach beyond conventional natural materials in order to synthesise tomorrow's 'designer material'. Material degradation into smaller components and subsequent release of encapsulated cells or cell-signalling agents have opened medically exploitable avenues, transforming the area of regenerative medicine into a dynamic and self-propagating branch of modern medicine. The aim to synthesise ever more refined scaffolding structures in order to create micro- and nanoenvironments resembling those found in natural tissues now represents an ever growing niche in the materials sciences. Recently, we have developed and conducted the world's first in-human tracheal transplantation using a non-degradable completely synthetic biomaterial. Fuelled by such clinical potential, we are currently developing a biodegradable version suitable for skin tissue engineering and paediatric applications. However, despite enormous efforts, current, as yet insurmountable challenges include precise biomaterial degradation within pre-determined spatial and temporal confines in an effort to release bio-signalling agents in such orchestrated fashion as to fully regenerate functioning tissues. In this review, the authors, almost anti-climactically, ask the readers to step out of the artificially over-constructed spiral of ever more convoluted scaffold fabrication techniques and consider the benefits of controllable bottom-up scaffold fabrication methods. It will further be investigated how scaffold designs and fabrication methods may influence degradation and subsequent release of incorporated elements. A focus will be placed on the delivery of growth factors, stem cells and therapeutic agents alone or in

  12. 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

  13. 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.

  14. Corrosion Detection of Reinforcement of Building Materials with Piezoelectric Sensors

    OpenAIRE

    Jia Peng

    2017-01-01

    The extensive use of reinforced materials in the construction industry has raised increased concerns about their safety and durability, while corrosion detection of steel materials is becoming increasingly important. For the scientific management, timely repair and health monitoring of construction materials, as well as to ensure construction safety and prevent accidents, this paper investigates corrosion detection on construction materials based on piezoelectric sensors. At present, the comm...

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

    Science.gov (United States)

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

    2017-01-01

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

  16. 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.

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

    Science.gov (United States)

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

    2016-08-01

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

  18. Study on the Application Mode and Legal Protection of Green Materials in Medical-Nursing Combined Building

    Science.gov (United States)

    Zhiyong, Xian

    2017-09-01

    In the context of green development, green materials are the future trend of Medical-Nursing Combined building. This paper summarizes the concept and types of green building materials. Then, on the basis of existing research, it constructs the green material system framework of Medical-Nursing Combined building, puts forward the application mode of green building materials, and studies the policy and legal protection of green material application.

  19. 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.

  20. 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

  1. 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.

  2. 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.

  3. 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.

  4. The application of phase change materials to cool buildings

    OpenAIRE

    Susman, Gideon

    2012-01-01

    This thesis was submitted for the degree of Engineering Doctorate in Environmental Technology and awarded by Brunel University. Five projects improve understanding of how to use PCM to reduce building cooling energy. Firstly, a post-installation energy-audit of an active cooling system with PCM tank revealed an energy cost of 10.6% of total cooling energy, as compared to an identical tankless system, because PCM under%cooling prevented heat rejection at night. Secondly, develop...

  5. Metabolites of Trichoderma species isolated from damp building materials.

    Science.gov (United States)

    McMullin, David R; Renaud, Justin B; Barasubiye, Tharcisse; Sumarah, Mark W; Miller, J David

    2017-07-01

    Buildings that have been flooded often have high concentrations of Trichoderma spores in the air while drying. Inhaled spores and spore and mycelial fragments contain large amounts of fungal glucan and natural products that contribute to the symptoms associated with indoor mould exposures. In this study, we considered both small molecules and peptaibol profiles of T. atroviride, T. koningiopsis, T. citrinoviride, and T. harzianum strains obtained from damp buildings in eastern Canada. Twenty-residue peptaibols and sorbicillin-derived metabolites (1-6) including a new structure, (R)-vertinolide (1), were characterized from T. citrinoviride. Trichoderma koningiopsis produced several koninginins (7-10), trikoningin KA V, and the 11-residue lipopeptaibols trikoningin KB I and trikoningin KB II. Trichoderma atroviride biosynthesized a mixture of 19-residue trichorzianine-like peptaibols, whereas T. harzianum produced 18-residue trichokindin-like peptaibols and the 11-residue harzianin HB I that was subsequently identified from the studied T. citrinoviride strain. Two α-pyrones, 6-pentyl-pyran-2-one (11) and an oxidized analog (12), were produced by both T. atroviride and T. harzianum. Aside from exposure to low molecular weight natural products, inhalation of Trichoderma spores and mycelial fragments may result in exposure to membrane-disrupting peptaibols. This investigation contributes to a more comprehensive understanding of the biologically active natural products produced by fungi commonly found in damp buildings.

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

    Energy Technology Data Exchange (ETDEWEB)

    Placek, V. E-mail: pla@ujv.cz; Bartonicek, B.; Hnat, V.; Otahal, B

    2003-08-01

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

  7. 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. 

  8. Phase Change Materials in Transparent Building Envelopes: A Strengths, Weakness, Opportunities and Threats (SWOT) Analysis

    OpenAIRE

    Ilaria Vigna; Lorenza Bianco; Francesco Goia; Valentina Serra

    2018-01-01

    Building envelopes can play a crucial role in building improvement efficiency, and the adoption of Phase Change Materials (PCMs), coupled with transparent elements, may: (i) allow a better control of the heat flows from/to the outdoor environment, (ii) increase the exploitation of solar energy at a building scale and (iii) modulate light transmission in order to prevent glare effects. Starting from a literature review, focused on experimental works, this research identifies the main possible ...

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

    DEFF Research Database (Denmark)

    Blumberga, Andra; Kass, Kristaps; Kamendere, Edite

    2016-01-01

    This report provides an analysis and evaluation of a state-of-the-art of internal insulation materials and methods for application in historic buildings, and review on methods, tools and guidelines used as decision making tools for implementation of internal insulation in historic buildings...

  10. Further developments of a poultice for electrochemical desalination of porous building materials

    DEFF Research Database (Denmark)

    Rörig-Dalgaard, Inge

    2015-01-01

    Salt induced deterioration of buildings is a frequently present problem and is in connection with traditional buildings a source for increased maintenance and costs. Especially in connection with Cultural Heritage (e.g. murals) even surface deterioration of original materials is unacceptable...

  11. building material preferences in warm-humid and hot-dry climates

    African Journals Online (AJOL)

    User

    2Department of Building Technology, College of Architecture and Planning, KNUST, Kumasi,. Ghana. ABSTRACT. This paper explores building materials preferences in the warm-humid and hot-dry climates in. Ghana. Using a combination of closed and open-ended questionnaires, a total of 1281 partici- pants (473 adults ...

  12. 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 (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal Disposal of Buildings and Other Improvements (without the...

  13. An experimental setup for measuring generation and transport of radon in building materials

    NARCIS (Netherlands)

    van der Pal, M.; Hendriks, N.A.; de Meijer, R.J.; van der Graaf, E.R.; de Wit, M.H.

    2001-01-01

    This study describes an approach for measuring and modelling diffusive and advective transport of radon through building materials. The goal of these measurements and model calculations is to improve our understanding concerning the factors influencing the transport of radon through building

  14. 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.

  15. Towards successful SPP treatment of local materials for road building

    CSIR Research Space (South Africa)

    Paige-Green, P

    2009-06-17

    Full Text Available of the increasing need for improvement of the rural road network and of roads associated with the Reconstruction and Development Program (RDP). Recommendations for testing materials for compatibility with SPPs are provided. In addition, a detailed construction...

  16. Exploring the Importance of Employing Bio and Nano-Materials for Energy Efficient Buildings Construction

    Directory of Open Access Journals (Sweden)

    Mona Naguib

    2017-03-01

    Full Text Available The continued and increasing use of ordinary building materials to house the ever-growing world population ensures growing contributions of carbon (C to the active carbon cycle through carbon dioxide (C02 emissions from combustion and chemical reactions in the raw material to the atmosphere. To minimize this, materials should be conserved, reduce their unnecessary use, produce them more benignly and make them last longer, recycle and reuse materials. Thus, paper will focus on exploring alternative building materials and systems that can be developed in order to balance atmospheric carbon dioxide.  It also presents the Bio-inspired architecture approach that embraces the eco-friendly practices of using Biomaterials and Nano-materials for sustainable dwelling construction through a number of examples that shows how a building can be strongly related to its site.

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

    Science.gov (United States)

    Was, Gary S.

    2007-08-01

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

  18. Factors relating to the degradation of materials in flat plate solar collectors

    Energy Technology Data Exchange (ETDEWEB)

    Wennerholm, H.; Vejsig Pedersen, P.

    1986-05-01

    The widespread use of flat plate solar collectors is being held back by lack of confidence in the long term durability of the component materials. Every material has a particular set or range of conditions under which it exhibits greatest ability to maintain its most desirable properties. This paper presents a review of the suitability of specific materials for components in flat plate solar collectors during exposure to weather conditions. Ambient factors that influence the atmospheric degradiation of materials are weather conditions, biological factors, mechanical factors, combinations of incompatible materials and application conditions. Weather conditions are, solar radiation, temperature, precipitation, humidity, wind, normal air components, and pollution. The most important factor promoting atmospheric corrosion of metals is the percentage of time when the critical humidity is exceeded. This period is called the time-of-wetness. Corrosion rates of most metals normally accelerate when metals are exposed to polluted environments. The agents constituting pollution that have been identified with corrosion can be listed as sulphur dioxide, hydrogen sulphide, ammonia, nitrogen oxides, sodium chloride, and particulate matter. The ultraviolet component in solar radiation plays an important role in the decomposition of organic materials. Other factors are heat, high humidities, oxygen, ozone, micro-biologic organisms, air pollution substances, wind, and dust. Synergistic associations are capable of effecting chemical transformations which are beyond the separate abilites of each degradation factor. And that affect both inorganic and organic materials. (author) 67 refs.

  19. Dendronized Metal Nanoparticles-Self-Organizing Building Blocks for the Design of New Functional Materials

    Science.gov (United States)

    2016-04-01

    AFRL-AFOSR-UK-TR-2016-0010 Dendronized metal nanoparticles - self-organizing building blocks for the design of new functional materials Bertrand...2015 4. TITLE AND SUBTITLE Dendronized metal nanoparticles - self-organizing building blocks for the design of new functional materials 5a. CONTRACT...restrictions or special markings are indicated, follow agency authorization procedures, e.g. RD/FRD, PROPIN, ITAR, etc. Include copyright

  20. Home Improvement: C57BL/6J Mice Given More Naturalistic Nesting Materials Build Better Nests

    OpenAIRE

    Hess, Sarah E; Rohr, Stephanie; Dufour, Brett D; Gaskill, Brianna N; Pajor, Edmond A; Garner, Joseph P

    2008-01-01

    Environmental enrichment of laboratory mice can improve the quality of research, but debate arises over the means of enrichment and its ability to be used in a sterile environment. One important form of enrichment is nesting material. Mice in the wild build dome-shaped, complex, multilayered nests, but this behavior is not seen in the laboratory, perhaps due to inappropriate nesting material rather than the nest-building ability of the mice. Here we focus on the use of naturalistic nesting ma...

  1. Building materials in eco-energy houses from Iraq and Iran

    Directory of Open Access Journals (Sweden)

    Amjad Almusaed

    2015-06-01

    Full Text Available Builders from the Western part of Asia are trained to make buildings that can fulfil certain required functions while giving full consideration to all sites and environmental conditions. The research covers the zone between Iraq and Iran. The first investigated region is the “Mesopotamian Marshes” or Iraqi-Iran Marshes, a wetland zone situated in southern Iraq and partially in southwestern Iran. The other region is a desert district, which includes a prominent part of the southern and western parts of Iraq and part of Iran. The last is the centre city of Basra. The building materials were the most important building element that affected the conformation of vernacular habitats from the western part of Asia in general and the Iraq–Iran area in particular. In this study, we needed to focus on the effects of ecological and energy-efficiency processes in creating vernacular habitats and the selection of optimal building systems and materials in this part of the world, which can be an essential point for sustainable environmental building processes in the future. Reeds, clay, straw, bricks, and wood were the most popular building materials used by builders from this region. The impact of building material on the environment embodies the essential method implicitly significant in this research to effectively determine traditional building materials in the environment, in addition to comparative analysis. This presents an essential factor of our analysis, in addition to the impact of environments on building systems. The main target of this study is to benefit designers and building engineers in their pursuit to find optimal and competent solutions suitable for specific local microclimates using traditional methods in the design process that are sustainable and ecological.

  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. Power plant wastes capitalization as geopolymeric building materials

    Science.gov (United States)

    Ciobanu, Gabriela; Litu, Loredana; Harja, Maria

    2017-11-01

    In this innovative study, we are present an investigation over the properties of geopolymeric materials prepared using ash supplied by power plant Iasi, Romania and sodium hydroxide solutions/pellets. Having as objective a minimum consumption of energy and materials was developed a class of advanced eco-materials. New synthesized materials can be used as a binder for cement replacement or for the removal/immobilization of pollutants from waste waters or soils. It offers an advanced and low cost-effective solution too many problems, where waste must be capitalized. The geopolymer formation, by hydrothermal method, is influenced by: temperature (20-600°C), alkali concentration (2M-6M), solid /liquid ratio (1-2), ash composition, time of heating (2-48 h), etc. The behaviour of the FTIR peak of 6M sample indicated upper quantity of geopolymer formation at the first stage of the reaction. XRD spectra indicated phases like sodalite, faujasite, Na-Y, which are known phases of geopolymer/zeolite. Advanced destroyed of ash particles due to geopolymerisation reaction were observed when the temperature was higher. At the constant temperature the percentage of geopolymer increases with increasing of curing time, from 4-48 h. Geopolymer materials are environmentally friendly, for its obtaining energy consumption, and CO2 emission is reduced compared to cement binder.

  4. 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

  5. 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.

  6. 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.

  7. Review of development survey of phase change material models in building applications.

    Science.gov (United States)

    Akeiber, Hussein J; Wahid, Mazlan A; Hussen, Hasanen M; Mohammad, Abdulrahman Th

    2014-01-01

    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.

  8. Science: 5th Class and 6th Class_ Materials - Exploring Marine Debris Degradation (Irish and English Version)

    OpenAIRE

    Institute, Marine

    2014-01-01

    The aim of the lesson plan is for the children identify and investigate a range of common materials in the immediate environment. The children will observe, investigate and experiment on the degradation effects the environment has on these items.

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

    OpenAIRE

    Kumar, Girish; Shivrayan, Amit

    2015-01-01

    Background and Objectives: The strength greatly influences the selection of core material because core must withstand forces due to mastication and para-function for many years. This study was conducted to evaluate certain mechanical properties of commonly used materials for direct core build-up, including visible light cured composite, polyacid modified composite, resin modified glass ionomer, high copper amalgam, and silver cermet cement. Materials and Methods: All the materials were manipu...

  10. Building materials for a sustainable future – cement

    CSIR Research Space (South Africa)

    Mapiravana, Joseph

    2014-03-01

    Full Text Available Concrete is second only to water in terms of the most consumed substances on earth. Cement is the "glue" which holds concrete together and it is therefore a construction material which is produced and consumed in huge quantities worldwide. Global...

  11. Mould growth on building materials under low water activities

    DEFF Research Database (Denmark)

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

    2004-01-01

    growth at RH > 90%, although 95% RH was needed to yield chemically detectable quantities of biomass. Almost exclusively only Penicillium, Aspergillus and Eurotium (contaminant) species grew on the materials. Production of secondary metabolites and mycotoxins decreased with humidity and the quantities...

  12. Effect of Material Variability and Mechanical Eccentricity on the Seismic Vulnerability Assessment of Reinforced Concrete Buildings

    Directory of Open Access Journals (Sweden)

    Mario Lucio Puppio

    2017-07-01

    Full Text Available The present paper deals with the influence of material variability on the seismic vulnerability assessment of reinforced concrete buildings. Existing r.c. buildings are affected by a strong dispersion of material strengths of both the base materials. This influences the seismic response in linear and nonlinear static analysis. For this reason, it is useful to define a geometrical parameter called “material eccentricity”. As a reference model, an analysis of a two storey building is presented with a symmetrical plan but asymmetrical material distribution. Furthermore, an analysis of two real buildings with a similar issue is performed. Experimental data generate random material distributions to carry out a probabilistic analysis. By rotating the vector that defines the position of the center of strength it is possible to describe a strength domain that is characterized by equipotential lines in terms of the Risk Index. Material eccentricity is related to the Ultimate Shear of non-linear static analyses. This relevant uncertainty, referred to as the variation of the center of strength, is not considered in the current European and Italian Standards. The “material eccentricity” therefore reveals itself to be a relevant parameter to considering how material variability affects such a variation.

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

    DEFF Research Database (Denmark)

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

    2017-01-01

    The presence of the fungal genus Chaetomium and its secondary metabolites in indoor environments is suspected to have a negative impact on human health and wellbeing. About 200 metabolites have been currently described from Chaetomium spp., but only the bioactive compound group, chaetoglobosins......, have been screened for, and thus detected in buildings. In this study, we used a liquid chromatography-high resolution mass spectrometry approach to screen both artificially and naturally infected building materials for all the Chaetomium metabolites described in the literature. Pure agar cultures were...... also investigated in order to establish differences between metabolite production in vitro and on building materials as well as comparison to non-indoor reference strains. On building materials six different chaetoglobosins were detected in total concentrations of up to 950 mg/m2 from C. globosum along...

  14. 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)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-02-15

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

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

    Science.gov (United States)

    1979-01-01

    current waste paper insulation systems. Remedy the situation or ban the use as may be appropriate. Recommendation: Prohibit use of unbacked and...polymeric materials, including plywood. • Recognize and assess the problems in current waste paper insulation systems so that the situation may be remedied ...diagram of carpet assembly. The primary backing is most often woven jute or nonwoven polypropylene. A typical adhesive latex, which locks the tufts

  17. Shear bond strength of different materials used as core build-up to ceramic.

    Science.gov (United States)

    Lilaj, Bledar; Franz, Alexander; Dangl, Viktoria; Dauti, Rinet; Moritz, Andreas; Cvikl, Barbara

    2017-10-01

    To determine the performance of a resin composite material specially developed for core build-ups in comparison with conventional restorative materials. 90 roughened ceramic blocs were divided into three groups; one group (n=30) was used for the core build-up material (Gradia Core) and the other two groups (n=30, each) were used for two conventional restorative materials (Tetric EvoCeram, Compoglass F). After adhesive fixation, specimens of each material were subdivided in accordance with the storage conditions (thermocycling or water storage). Shear bond strength was measured and fracture behavior was analyzed. Gradia Core presented significantly higher shear bond strength values than the conventional restorative material Tetric EvoCeram, both after 24 hours water storage as well as after thermocycling. Compoglass F did not show any statistically significant differences compared to the other materials, independent of the storage condition. However, Compoglass F resulted in numerically higher shear bond values than Tetric EvoCeram, but lower shear bond values than Gradia Core. Within the same materials, no statistically significant differences occurred regarding the storage conditions. The specific core build-up material provided stronger bonding properties when luted to feldspar ceramic than conventional restorative materials, making it a suitable supporting material when high-quality esthetic restorations are needed for restoring decayed, but vital teeth.

  18. 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.

  19. Thermal/chemical degradation of ceramic candle filter materials. Final report, September 1988--October 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-01-01

    High-temperature ceramic candle filters are being developed for use in advanced power generation systems such as the Integrated Gasification Combined Cycle (IGCC), Pressurized Fluidized-Bed Combustor (PFBC), and Direct Coal-Fired Turbine (DCFT). The direct firing of coal produces particulate matter which must be removed to meet both environmental and process limitations. The ceramic candles increase the efficiency of the advanced power generation systems and protect downstream equipment from erosion and impingement of particulate matter in the hot exhaust gases. Ceramic candle filters are rigid, closed-ended (capped on one side) porous cylinders which generally have a flange on the open-ended side. The flange at the open end allows the candle to be suspended by a tubesheet in the filter vessel. Candle filters have shown promise, but have also encountered durability problems during use in hostile, high-temperature environments. Limitations in the candle lifetime lower the economic advantages of using candle filters for this application. Candles typically fail by cracking at the flange or in the body of the candle. The objective of this project was to test and analyze ceramic candle filter materials and to evaluate the degradation mechanisms. The tests were conducted such that the effects of each degradation mechanism could be examined. Separately. The overall objective of the project was to: (a) develop a better understanding of the thermal and chemical degradation mechanisms of ceramic candle filter materials in advanced coal utilization projects, (b) develop test procedures, and (c) recommend changes to increase filter lifetime. 15 refs., 67 figs., 17 tabs.

  20. Identification and cause of decay of building materials used in the architectural heritage of Bizerte city (Tunisia)

    Science.gov (United States)

    Zoghlami, Karima; Lopez-Arce, Paula; Navarro, Antonia; Zornoza-Indart, Ainara; Gómez, David

    2017-04-01

    Monuments and historical buildings of Bizerte show a disturbing state of degradation. In order to propose a compatible materials for the restauration works such as stone of substitution and restauration mortars, a geological context was analysed with the objectif to localize historical quarries accompanied by a sedimentological study to identify the exploited geological formations. Petrophysical and chemical caracterisation of both stone and mortars have been carried out. With the aim to determine the origin of the erosion and the degree of stone decay, a combination of micro-destructive and non-destructive techniques have been used on-site and in-lab. Moisture measurements, ultrasonic velocity propagation and water absorption by Karsten pipe test together with polarized light and fluorescence optical microscopy, mercury intrusion porosimetry and ion chromatography analyses were carried out to perform petrophysical characterization of stone samples and determination of soluble salts. For the characterization of mortars, granulometric study was performed to determine the nature of components and their grain size distribution. Thin sections of mortar samples were examined for the petrographical and mineralogical characterization. X-ray diffraction (XRD) analysis of finely pulverized samples was performed in order to identify the mineral crystalline phases of the mortars. Thermal analyses [thermogravimetry (TG)] were performed in order to determine the nature of the binder and its properties. Porosity was determined following UNE-EN 1936 (2007) standart test. Geological and petrographical study showed that historical buildings are essentially built with high porous bioclastic calcarenite partially cemented by calcite which is Würm in age and outcrops all along the northern coast of Bizerte where several historical quarries were identified. Occasionally, two other types of lithologies were used as building stones and they correspond to two varieties of oligocene

  1. Home improvement: C57BL/6J mice given more naturalistic nesting materials build better nests.

    Science.gov (United States)

    Hess, Sarah E; Rohr, Stephanie; Dufour, Brett D; Gaskill, Brianna N; Pajor, Edmond A; Garner, Joseph P

    2008-11-01

    Environmental enrichment of laboratory mice can improve the quality of research, but debate arises over the means of enrichment and its ability to be used in a sterile environment. One important form of enrichment is nesting material. Mice in the wild build dome-shaped, complex, multilayered nests, but this behavior is not seen in the laboratory, perhaps due to inappropriate nesting material rather than the nest-building ability of the mice. Here we focus on the use of naturalistic nesting materials to test whether they improve nest quality through the use of a 'naturalistic nest score' system; we also focus on materials that can be sterilized and easily used in existing housing systems. We first determined whether C57BL/6J mice build naturalistic nests when given shredded paper strips. We then compared these shredded paper strips with other commonly used nesting enrichments (facial tissues and compressed cotton squares). Nests were scored for 6 d. We found that the shredded paper strips allowed the mice to build higher quality nests than those built with any of the other materials. Nests built with tissues were of intermediate quality, and nests built with compressed cotton squares were of poor quality, similar to those built by the control group. These results suggest that C57BL/6J mice given appropriate nesting materials can build nests similar to those built by their wild counterparts.

  2. Biazulene diimides: a new building block for organic electronic materials.

    Science.gov (United States)

    Xin, Hanshen; Ge, Congwu; Yang, Xiaodi; Gao, Honglei; Yang, Xiaochun; Gao, Xike

    2016-11-01

    Azulene, a 10-π-electron isomer of naphthalene, is a nonbenzenoid bicyclic aromatic hydrocarbon with a beautiful blue color and a large dipole moment. We present here the first class of azulene-based aromatic diimides, 2,2'-biazulene-1,1',3,3'-tetracarboxylic diimides (BAzDIs), which comprise a 2,2'-biazulene moiety and two seven-membered imide groups. DFT calculations, thermal, optical and electrochemical properties of two BAzDI derivatives as well as single crystal analysis and the charge transport behavior were studied. The results demonstrate that BAzDIs have unique photophysical properties and are promising for organic electronic materials.

  3. Graphene-like boron nitride modified bismuth phosphate materials for boosting photocatalytic degradation of enrofloxacin.

    Science.gov (United States)

    Chen, Zhigang; Chen, Xiaoliu; Di, Jun; Liu, Yiling; Yin, Sheng; Xia, Jiexiang; Li, Huaming

    2017-04-15

    A novel graphene-like BN modified BiPO 4 material was prepared for the first time via a simple solvothermal process with the assistance of reactable ionic liquid 1-decyl-3-methylimidazolium dihydrogen phosphate ([Omim]H 2 PO 4 ). The as-prepared photocatalyst was characterized by XRD, FT-IR, Raman, XPS, TEM, DRS, BET, PL, EIS and ESR to investigate the structure, morphology, optical property, surface area, electrical property and active species. The photocatalytic activities of graphene-like BN/BiPO 4 materials were evaluated by the degradation of antibiotic enrofloxacin (ENR) under UV light irradiation and the 1wt% graphene-like BN/BiPO 4 displayed the best activity among the BN/BiPO 4 composites. The enhanced photocatalytic activity for the removal of enrofloxacin was attributed to higher separation efficiency of photogenerated electron-hole pairs, and the generated more O 2 - and OH radicals when the BN was modified on BiPO 4 . Moreover, a probable degradation mechanism was proposed for the improved photocatalytic activity of BN modified BiPO 4 . Copyright © 2016 Elsevier Inc. All rights reserved.

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

    NARCIS (Netherlands)

    Ganendra, G; De Muynck, W; Ho, A.; Hoefman, S.; De Vos, P.; Boeckx, P.; Boon, N.

    2014-01-01

    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 (similar to 20 % (v/v)) and low (similar to 100 ppmv) methane

  5. Comparison of salt solution and air drying methods for moisture fixation in highly porous building materials

    DEFF Research Database (Denmark)

    Antonov, Yovko Ivanov; Jensen, Rasmus Lund; Møldrup, Per

    2017-01-01

    building materials by a standardized testing method, using saturated salt solutions. Furthermore, results from the standard method are compared to values of moisture content for the same materials, obtained by air-drying at different relative humidity. This is done with the aim to compare the findings from...

  6. Application of earth building materials for low-income housing in the ...

    African Journals Online (AJOL)

    The characteristics, properties, problems and other factors associated with earth materials for building houses, especially in the tropical regions of the world are identified. The inter-relationships among these factors which inhibit the adoption of earth materials and the recommendations for overcoming the problems in a ...

  7. A Study on Variation of Thermal Characteristics of Insulation Materials for Buildings According to Actual Long-Term Annual Aging Variation

    Science.gov (United States)

    Choi, Hyun-Jung; Kang, Jae-Sik; Huh, Jung-Ho

    2018-01-01

    Insulation materials used for buildings are broadly classified as organic insulation materials or inorganic insulation materials. Foam gas is used for producing organic insulation materials. The thermal conductivity of foam gas is generally lower than that of air. As a result, foam gas is discharged over time and replaced by outside air that has relatively less thermal resistance. The gas composition ratio in air bubbles inside the insulation materials changes rapidly, causing the performance degradation of insulation materials. Such performance degradation can be classified into different stages. Stage 1 appears to have a duration of 5 years, and Stage 2 takes a period of over 10 years. In this study, two insulation materials that are most frequently used in South Korea were analyzed, focusing on the changes thermal resistance for the period of over 5000 days. The measurement result indicated that the thermal resistance of expanded polystyrene fell below the KS performance standards after about 80-150 days from its production date. After about 5000 days, its thermal resistance decreased by 25.7 % to 42.7 % in comparison with the initial thermal resistance. In the case of rigid polyurethane, a pattern of rapid performance degradation appeared about 100 days post-production, and the thermal resistance fell below the KS performance standards after about 1000 days. The thermal resistance decreased by 22.5 % to 27.4 % in comparison with the initial thermal resistance after about 5000 days.

  8. Rapid assessment methodology in NORM measurements from building materials of Uzbekistan.

    Science.gov (United States)

    Safarov, A A; Safarov, A N; Azimov, A N; Darby, I G

    2017-04-01

    Utilizing low cost NaI(Tl) scintillation detector systems we present methodology for the rapid screening of building material samples and the determination of their Radium Equivalent Activity (Raeq). Materials from Uzbekistan as a representative developing country have been measured and a correction coefficient for Radium activity is deduced. The use of the correction coefficient offers the possibility to decrease analysis times thus enabling the express measurement of a large quantity of samples. The reduction in time, cost and the use of inexpensive equipment can democratize the practice of screening NORM in building materials in the international community. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. 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.

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

    Science.gov (United States)

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

    2017-02-01

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

  11. 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...... in 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...

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

    DEFF Research Database (Denmark)

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

    2008-01-01

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

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

    Science.gov (United States)

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

    2013-12-01

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

  14. 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.

  15. 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

  16. 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.

  17. Study on application of concrete sandwich insulation material in library building insulation

    Science.gov (United States)

    Yang, Zengzhang

    2017-06-01

    Energy shortage is the short slab that restricts the development of social economy, and the rational and effective use of energy is the principle of sustainable development. Building energy consumption accounts for about 30% of total social energy consumption, and this ratio has continued to rise, so the energy saving potential is great in the construction sector. In view of the building energy consumption problem, we produce green insulation building materials with the crop straw, and improve the construction of hot and humid environment. In this paper, we take concrete sandwich straw blocks in library building as the research object, through the experiment to test its winter heat consumption and summer power consumption indicators, carry out experimental study on thermal insulation performance, and explore the overall thermal and energy saving performance of concrete sandwich straw blocks in library building.

  18. 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

    2016-04-01

    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.

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

    Science.gov (United States)

    Moharram, B M; Suliman, M N; Zahran, N F; Shennawy, S E; El Sayed, A R

    2012-01-01

    Using of building materials containing naturally occurring radionuclides as (238)U, (232)Th and (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 (238)U, (232)Th and (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 (238)U, (232)Th and (40)K, from the selected samples, were in the range 14.15-60.64, 2.75-84.66 and 7.35-554.4Bqkg(-1), respectively. The average indoor absorbed dose rates in air ranged from 0.005μGyh(-1) to 0.071μGyh(-1) and the corresponding population-weighted annual effective dose due to external gamma radiation varies from 0.025 to 0.345mSv. An outdoor dose rate for typical building samples in addition to some radiological hazards has been introduced for comparison. Copyright © 2011 Elsevier Ltd. All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    Mottaeva Asiiat

    2016-01-01

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

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

    Directory of Open Access Journals (Sweden)

    J. Drchalová

    2000-01-01

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

  2. Natural radionuclide and radiological assessment of building materials in high background radiation areas of Ramsar, Iran.

    Science.gov (United States)

    Bavarnegin, Elham; Moghaddam, Masoud Vahabi; Fathabadi, Nasrin

    2013-04-01

    Building materials, collected from different sites in Ramsar, a northern coastal city in Iran, were analyzed for their natural radionuclide contents. The measurements were carried out using a high resolution high purity Germanium (HPGe) gamma-ray spectrometer system. The activity concentration of (226)Ra, (232)Th, and (40)K content varied from below the minimum detection limit up to 86,400 Bqkg(-1), 187 Bqkg(-1), and 1350 Bqkg(-1), respectively. The radiological hazards incurred from the use of these building materials were estimated through various radiation hazard indices. The result of this survey shows that values obtained for some samples are more than the internationally accepted maximum limits and as such, the use of them as a building material pose significant radiation hazard to individuals.

  3. 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.

  4. Photocatalytic degradation of textile dye X-3B using polyoxometalate-TiO2 hybrid materials.

    Science.gov (United States)

    Jin, Hongxiao; Wu, Qingyin; Pang, Wenqin

    2007-03-06

    Titanium dioxide functionalized with Keggin type polyoxometalate (POMs) [X(n+)W(12)O(40)]((8-n)-) (XW(12); X(n+)=P(5+), Si(4+), Ge(4+)) were prepared by sol-gel method. The Keggin structure and dispersion state of POMs were monitored by FT-IR and XRD. The composites showed higher photocatalytic activity than pure TiO(2), pure POMs or mechanical mixture of TiO(2) and POMs for X-3B degradation. Among the three POMs-TiO(2) hybrid materials, the reactivity was: PW(12)>SiW(12)>GeW(12). With different loading weights for the same POMs, the reactivity followed the order: 30wt.%>15wt.%>45wt.%.

  5. 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)

  6. 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.

  7. 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 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...

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

    Science.gov (United States)

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

    2016-10-01

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

  9. 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)); Gdowski, G.E. (Science and Engineering Associates, Inc., Pleasanton, CA (USA))

    1988-06-01

    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.

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

    Science.gov (United States)

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

    2016-12-01

    Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are a large group of important chemical compounds with unique and useful physico-chemical properties, widely produced and used in many applications. However, due to the toxicity, bioaccumulation and long-range transport potential of certain PFASs, they are of significant concern to scientists and policy makers. To assess human exposure to PFASs, it is necessary to understand the concentrations of these emerging contaminants in our environment, and particularly environments where urban population spend most of their time, i.e. buildings and vehicles. A total of 126 samples of building materials, consumer products, car interior materials and wastes were therefore analyzed for their content of key PFASs - 15 perfluoroalkyl acids (PFAAs). At least one of the target PFAAs was detected in 88% of all samples. The highest concentration of Σ15PFAAs was found in textile materials (77.61 μg kg(-1)), as expected, since specific PFAAs are known to be used for textile treatment during processing. Surprisingly, PFAAs were also detected in all analyzed composite wood building materials, which were dominated by perfluoroalkyl carboxylic acids with 5-8 carbons in the chain (Σ4PFCAs up to 32.9 μg kg(-1)). These materials are currently widely used for building refurbishment, and this is the first study to find evidence of the presence of specific PFASs in composite wood materials. Thus, in addition to consumer products treated with PFASs, materials used in the construction of houses, schools and office buildings may also play an important role in human exposure to PFASs. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

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

    2013-03-01

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

  12. A diffusivity model for predicting VOC diffusion in porous building materials based on fractal theory

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yanfeng, E-mail: lyfxjd@163.com; Zhou, Xiaojun; Wang, Dengjia; Song, Cong; Liu, Jiaping

    2015-12-15

    Highlights: • Fractal theory is introduced into the prediction of VOC diffusion coefficient. • MSFC model of the diffusion coefficient is developed for porous building materials. • The MSFC model contains detailed pore structure parameters. • The accuracy of the MSFC model is verified by independent experiments. - Abstract: Most building materials are porous media, and the internal diffusion coefficients of such materials have an important influences on the emission characteristics of volatile organic compounds (VOCs). The pore structure of porous building materials has a significant impact on the diffusion coefficient. However, the complex structural characteristics bring great difficulties to the model development. The existing prediction models of the diffusion coefficient are flawed and need to be improved. Using scanning electron microscope (SEM) observations and mercury intrusion porosimetry (MIP) tests of typical porous building materials, this study developed a new diffusivity model: the multistage series-connection fractal capillary-bundle (MSFC) model. The model considers the variable-diameter capillaries formed by macropores connected in series as the main mass transfer paths, and the diameter distribution of the capillary bundles obeys a fractal power law in the cross section. In addition, the tortuosity of the macrocapillary segments with different diameters is obtained by the fractal theory. Mesopores serve as the connections between the macrocapillary segments rather than as the main mass transfer paths. The theoretical results obtained using the MSFC model yielded a highly accurate prediction of the diffusion coefficients and were in a good agreement with the VOC concentration measurements in the environmental test chamber.

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

    Science.gov (United States)

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

    2010-03-01

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

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

    Directory of Open Access Journals (Sweden)

    Nachawit T.

    2012-01-01

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

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

    Science.gov (United States)

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

    2016-09-01

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

  16. Time-Variant Reliability Analysis for Rubber O-Ring Seal Considering Both Material Degradation and Random Load

    OpenAIRE

    Baopeng Liao; Bo Sun; Meichen Yan; Yi Ren; Weifang Zhang; Kun Zhou

    2017-01-01

    Due to the increase in working hours, the reliability of rubber O-ring seals used in hydraulic systems of transfer machines will change. While traditional methods can only analyze one of the material properties or seal properties, the failure of the O-ring is caused by these two factors together. In this paper, two factors are mainly analyzed: the degradation of material properties and load randomization by processing technology. Firstly, the two factors are defined in terms of material failu...

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

    Science.gov (United States)

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

    2015-01-01

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

  18. Phase Change Materials in Transparent Building Envelopes: A Strengths, Weakness, Opportunities and Threats (SWOT Analysis

    Directory of Open Access Journals (Sweden)

    Ilaria Vigna

    2018-01-01

    Full Text Available Building envelopes can play a crucial role in building improvement efficiency, and the adoption of Phase Change Materials (PCMs, coupled with transparent elements, may: (i allow a better control of the heat flows from/to the outdoor environment, (ii increase the exploitation of solar energy at a building scale and (iii modulate light transmission in order to prevent glare effects. Starting from a literature review, focused on experimental works, this research identifies the main possible integrations of PCMs in transparent/translucent building envelope components (in glazing, in shutters and in multilayer façade system in order to draw a global picture of the potential and limitations of these technologies. Transparent envelopes with PCMs have been classified from the simplest “zero” technology, which integrates the PCM in a double glass unit (DGU, to more complex solutions—with a different number of glass cavities (triple glazed unit TGU, different positions of the PCM layer (internal/external shutter, and in combination with other materials (TIM, aerogel, prismatic solar reflector, PCM curtain controlled by an electric pump. The results of the analysis have been summarised in a Strengths, Weakness, Opportunities and Threats (SWOT analysis table to underline the strengths and weaknesses of transparent building envelope components with PCMs, and to indicate opportunities and threats for future research and building applications.

  19. 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

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

    Directory of Open Access Journals (Sweden)

    Jiyoung Park

    2017-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Andrea Arrighetti

    2017-01-01

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

  2. PHASE CHANGE MATERIALS FOR DAY LIGHTING AND GLAZED INSULATION IN BUILDINGS

    Directory of Open Access Journals (Sweden)

    LOKESH JAIN

    2009-09-01

    Full Text Available This paper presents the experimental solar transmittance measurements of commercial grade Phase Change Material (PCM. The effects of ambient temperature, solar radiation and thickness on transmittance have been studied. The study indicates that the PCM has higher transmittance than water. High transmittance, low thermal conductivity and high latent heat of fusion make it suitable transparent insulating building material (i.e. Window, sky roof etc..

  3. The role of absorbent building materials in moderating changes of relative humidity

    DEFF Research Database (Denmark)

    Padfield, Tim

    The problem studied in this work is, how porous, absorbent materials surroundning or placed in a room influence the relative humidity of the room. This is of interest in designing precautions and machinery to monitor the indoor climate in museums and dwelling rooms. - A novel technique for the in...... for the investigation of the moisture buffering capacity of building materials is introduced, measuring the resulting flux in the system instead of the resulting relative humidity....

  4. 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.

  5. High-Capacity and Photoregenerable Composite Material for Efficient Adsorption and Degradation of Phenanthrene in Water.

    Science.gov (United States)

    Liu, Wen; Cai, Zhengqing; Zhao, Xiao; Wang, Ting; Li, Fan; Zhao, Dongye

    2016-10-18

    We report a novel composite material, referred to as activated charcoal supported titanate nanotubes (TNTs@AC), for highly efficient adsorption and photodegradation of a representative polycyclic aromatic hydrocarbon (PAH), phenanthrene. TNTs@AC was prepared through a one-step hydrothermal method, and is composed of an activated charcoal core and a shell of carbon-coated titanate nanotubes. TNTs@AC offered a maximum Langmuir adsorption capacity of 12.1 mg/g for phenanthrene (a model PAH), which is ∼11 times higher than the parent activated charcoal. Phenanthrene was rapidly concentrated onto TNTs@AC, and subsequently completely photodegraded under UV light within 2 h. The photoregenerated TNTs@AC can then be reused for another adsorption-photodegradation cycle without significant capacity or activity loss. TNTs@AC performed well over a wide range of pH, ionic strength, and dissolved organic matter. Mechanistically, the enhanced adsorption capacity is attributed to the formation of carbon-coated ink-bottle pores of the titanate nanotubes, which are conducive to capillary condensation; in addition, the modified microcarbon facilitates transfer of excited electrons, thereby inhibiting recombination of the electron-hole pairs, resulting in high photocatalytic activity. The combined high adsorption capacity, photocatalytic activity, and regenerability/reusability merit TNTs@AC a very attractive material for concentrating and degrading a host of micropollutants in the environment.

  6. 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. Copyright © 2016 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  7. Thermal Insulating Properties of Straw-Filled Environmentally Friendly Building Materials

    Directory of Open Access Journals (Sweden)

    Petkova-Slipets Rositsa

    2017-06-01

    Full Text Available The paper presents results of a research for determination of a few general thermal-physical properties of environmentally friendly building materials made by clay, sand and straw. The aim of this study is to establish their heat insulating and energy-efficient capacity. All specific measurements were carried out by using the newest generation thermal conductivity analyser Mathis TCi.

  8. 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…

  9. 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…

  10. Konference report: 8th International Conference on Durability of Building Materials and Components

    DEFF Research Database (Denmark)

    Rudbeck, Claus Christian

    1999-01-01

    The report describes the activities of the author (2 oral presentations, 1 session chairman, participation in ISO/TC59/SC14 and CIB W80 meeetings) during the 8th International Conference on Durability of Building Materials and Components held in Vancouver, Canada from 30 May 1999 to 6 June 1999....

  11. A dynamic experimental study on the evaporative cooling performance of porous building materials

    Science.gov (United States)

    Zhang, Yu; Zhang, Lei; Meng, Qinglin; Feng, Yanshan; Chen, Yuanrui

    2017-08-01

    Conventional outdoor dynamic and indoor steady-state experiments have certain limitations in regard to investigating the evaporative cooling performance of porous building materials. The present study investigated the evaporative cooling performance of a porous building material using a special wind tunnel apparatus. First, the composition and control principles of the wind tunnel environment control system were elucidated. Then, the meteorological environment on a typical summer day in Guangzhou was reproduced in the wind tunnel and the evaporation process and thermal parameters of specimens composed of a porous building material were continuously measured. Finally, the experimental results were analysed to evaluate the accuracy of the wind tunnel environment control system, the heat budget of the external surface of the specimens and the total thermal resistance of the specimens and its uncertainty. The analysis results indicated that the normalized root-mean-square error between the measured value of each environmental parameter in the wind tunnel test section and the corresponding value input into the environment control system was thermal resistance of the wet specimen was approximately doubled, indicating that the evaporation process of the porous building material could significantly improve the thermal insulation performance of the specimen.

  12. Effect of sodium hypochlorite contamination on microhardness of dental core build-up materials.

    Science.gov (United States)

    Wegehaupt, Florian Just; Betschart, Jasmin; Attin, Thomas

    2010-08-01

    This study aimed to determine the influence of sodium hypochlorite (NaOCl) contamination on the microhardness of build-up composites. Fifty-two samples, from each of three build-up materials (LuxaCore Dual, MultiCore flow and Rebilda DC) were prepared. Half of the samples from each material were stored in physiologic saline (baseline control) while the other halves were stored in NaOCl. After 1 h, the samples were rinsed with tap water, cut axially and measured for Knoop hardness at different depth levels. The results were analysed by ANOVA and unpaired t-tests (pmicrohardness were observed for LuxaCore Dual up to 0.2 mm, Rebilda DC up to 0.3 mm, and for MultiCore flow up to 0.4 mm under the surface level. Contact with sodium hypochlorite on build-up materials causes reduction of the microhardness. The softening is not only limited on the surface, but can also be found in deeper layers of build-up materials.

  13. BOKS: A Rule-Based System in Support of the Dutch Building Materials Regulations

    NARCIS (Netherlands)

    Spronck, P.H.M.; Schilstra, K.O.

    2000-01-01

    BOKS is a knowledge based system which implements the "Bouwstoffenbesluit" (Bsb), the Dutch regulations on the use of building materials. Since the Bsb is a complex set of rules, which many people need to adhere to, a knowledge based system was seen as an ideal way to allow people to check whether

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

    Science.gov (United States)

    McClure, F. A.

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

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

    NARCIS (Netherlands)

    Xing, W.

    2004-01-01

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

  16. The application study on building materials with computer color quantification system

    Science.gov (United States)

    Li, Zhendong; Yu, Haiye; Li, Hongnan; Zhao, Hongxia

    2006-01-01

    The first impression of any building to a person is its exterior and decoration, and therefore the quality of decoration project shows the more important position in building project. A lot of projects produce quality problem because of the material color difference, which exists universally at the common project, and is often found at the high-grade decoration; therefore, how to grasp and control the color change of building materials, and carry out color quantification, it has the very important meaning. According to the color theory, a computer vision system used in color quantification measurement is established, the standard illuminant A is selected as the light source. In order to realize the standardization of color evaluation, the mutual conversion between RGB and XYZ color space is studied, which is realized by the BP network. According to the colorimetry theory, the computer program is compiled in order to establish the software system, and realize the color quantitative appraisement in whole color gamut. LCH model is used at quantifying the color of building materials, and L *a *b * model is used at comparing the color change. If the wooden floor is selected and laid improperly during family fitment, it is easy to present "flower face". The color also arises greater discrepancy using the laths of same tree. We can give the laying scheme using the color quantification system; at the same time, the color difference problem laying stone materials is also studied in this paper, and the solution scheme has been given using this system.

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

    Science.gov (United States)

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

  18. 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

  19. 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

  20. ANALYTICAL MODEL OF DAMAGED AIRCRAFT SKIN BONDED REPAIRS ASSUMING THE MATERIAL PROPERTIES DEGRADATION

    Directory of Open Access Journals (Sweden)

    2016-01-01

    Full Text Available The search of optimal variants for composite repair patches allows to increase the service life of a damaged air- plane structure. To sensibly choose the way of repair, it is necessary to have a computational complex to predict the stress- strain condition of "structure-adhesive-patch" system and to take into account the damage growth considering the material properties change. The variant of the computational complex based on inclusion method is proposed.For calculation purposes the repair bonded joint is divided into two areas: a metal plate with patch-shaped hole and a "patch-adhesive layer-skin" composite plate (inclusion.Calculation stages:Evaluation of the patch influence to the skin stress-strain condition, stress distribution between skin and patch in the case of no damage. Calculation of the stress-strain condition is performed separately for the skin with hole and for the inclusion; solutions are coupled based on strain compatibility.Definition of the damage growth parameters at new stress-strain condition due to bonded patch existence. Skincrack stress intensity factors are found to identify the crack growth velocity. Patch is modelled as a set of "springs" bridging the crack.Degradation analysis of elasticity properties for the patch material.Repair effectiveness is evaluated with respect to crack growth velocity reduction in the initial material in compari- son with the case of the patch absence.Calculation example for the crack repair effectiveness depending on number of loading cycles for the 7075-T6 aluminum skin is given. Repair patches are carbon-epoxy, glass-epoxy and boron-epoxy material systems with quasi- isotropic layup and GLARE hybrid metal-polymeric material.The analysis shows the high effectiveness of the carbon-epoxy patch. Due to low stiffness, the glass-epoxy patchdemonstrates the least effectiveness. GLARE patch containing the fiberglass plies oriented across the crack has the same effectiveness as the carbon and

  1. Enhancement of global flood damage assessments using building material based vulnerability curves

    Science.gov (United States)

    Englhardt, Johanna; de Ruiter, Marleen; de Moel, Hans; Aerts, Jeroen

    2017-04-01

    This study discusses the development of an enhanced approach for flood damage and risk assessments using vulnerability curves that are based on building material information. The approach draws upon common practices in earthquake vulnerability assessments, and is an alternative for land-use or building occupancy approach in flood risk assessment models. The approach is of particular importance for studies where there is a large variation in building material, such as large scale studies or studies in developing countries. A case study of Ethiopia is used to demonstrate the impact of the different methodological approaches on direct damage assessments due to flooding. Generally, flood damage assessments use damage curves for different land-use or occupancy types (i.e. urban or residential and commercial classes). However, these categories do not necessarily relate directly to vulnerability of damage by flood waters. For this, the construction type and building material may be more important, as is used in earthquake risk assessments. For this study, we use building material classification data of the PAGER1 project to define new building material based vulnerability classes for flood damage. This approach will be compared to the widely applied land-use based vulnerability curves such as used by De Moel et al. (2011). The case of Ethiopia demonstrates and compares the feasibility of this novel flood vulnerability method on a country level which holds the potential to be scaled up to a global level. The study shows that flood vulnerability based on building material also allows for better differentiation between flood damage in urban and rural settings, opening doors to better link to poverty studies when such exposure data is available. Furthermore, this new approach paves the road to the enhancement of multi-risk assessments as the method enables the comparison of vulnerability across different natural hazard types that also use material-based vulnerability curves

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

    Science.gov (United States)

    2014-07-01

    quality. * One quantitative method of measuring bond strength is ASTM D7522 / D7522M...Strengthening Concrete Structures. ERDC/CERL TR-14-9 25 References ASTM D7522 / D7522M – 09, “Standard Test Method for Pull-Off Strength for FRP...ERDC/CERL TR-14-9 D93 ERDC/CERL TR-14-9 D94 ERDC/CERL TR-14-9 D95 ERDC/CERL TR-14-9 D96 ERDC/CERL TR-14-9 D97 ERDC/CERL TR-14-9 D98

  3. 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.

  4. 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).

  5. COMPARATIVE STUDY ON THE CHOICE OF BUILDING MATERIALS FOR CONSTRUCTING A HOUSE

    Directory of Open Access Journals (Sweden)

    Adelaida Cristina HONŢUŞ

    2014-12-01

    Full Text Available For some, building one’s own home can be a unique opportunity in a lifetime. That is why the choice of project, materials and finishings is paramount. Any homeowner wants a comfortable house, which is durable, insulated, easy to maintain, and, why not, built with least costs, but using quality materials. Brick and Autoclaved Aerated Concrete (AAC are the most common materials on the Romanian market when it comes to building a house. Although these two materials have been on the market for years, most manufacturers still use them because of the advantages presented in time by houses constructed out of them. Brick or AAC homes have a longer life compared to the ones erected with other construction materials and feature increased safety in terms of structural strength. Also, brick or AAC houses have the advantage of much better sound insulation than wood, for example. In our country there are sufficient resources for masonry, depending on the cost invested by the owner, at the same time displaying the characteristic properties that can provide the required safety of the building. Ceramic bricks and blocks produced here have diverse sizes and shapes, being able to meet the demands of any architect and customer

  6. 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.

  7. Remote Sensing to Estimate Saturation Differences of Chosen Building Materials Using Terrestrial Laser Scanner

    Science.gov (United States)

    Suchocki, Czesław; Katzer, Jacek; Panuś, Arkadiusz

    2017-06-01

    Terrestrial Laser Scanner (TLS) method which is commonly used for geodetic applications has a great potential to be successfully harnessed for multiple civil engineering applications. One of the most promising uses of TLS in construction industry is remote sensing of saturation of building materials. A research programme was prepared in order to prove that harnessing TLS for such an application is viable. Results presented in the current paper are a part of a much larger research programme focused on harnessing TLS for remote sensing of saturation of building materials. The paper describes results of the tests conducted with an impulse scanner Leica C-10. Tests took place both indoors (in a stable lab conditions) and outdoors (in a real environment). There were scanned specimens of the most popular building materials in Europe. Tested specimens were dried and saturated (including capillary rising moisture). One of the tests was performed over a period of 95 hours. Basically, a concrete specimen was scanned during its setting and hardening. It was proven that absorption of a laser signal is influenced by setting and hardening of concrete. Outdoor tests were based on scanning real buildings with partially saturated facades. The saturation assessment was based on differences of values of intensity. The concept proved to be feasible and technically realistic.

  8. Indoor Pollution Emissions from Building Materials; Case of Study: Gypsum Boards Indoor Pollution Emissions from Building Materials; Case of Study: Gypsum Boards

    Directory of Open Access Journals (Sweden)

    Silverio Hernández Moreno

    2012-02-01

    Full Text Available Este reporte presenta una evaluación de las emisiones de materiales de construcción, al interior de los edificios que pueden causar daño a la salud de los usuarios durante la ocupación, pues emiten sustancias tóxicas al interior de los edificios. Este reporte presenta un caso de studio que evalúa a los tableros de yeso, frecuentemente usados en la construcción de muros divisorios y falsos plafones. La parte experimental se basa en un espacio tridimensional el cual simula un cuarto de cualquier tipo de edificación; por ejemplo: un salón de clases u oficina. Las condiciones ambientales al interior, tales como: ventilación, temperatura y humedad, afectan directamente las emisiones de sustancias químicas por los materiales de construcción. La metodología se basa en la comparación de materiales convencionales y materiales alternativos con distinta composición y similares características, en donde usamos métodos de prueba, condiciones ambientales, instrumentos y herramientas similares. Este es un estudio muy importante para entender los problemas relacionadoscon la contaminación ambiental, específicamente del aire y sus efectos en el interior de los edificios, y que se relaciona directamente con la salud pública e indirectamente con los sistemas constructivos y la selección de materiales en los edificios. Las pruebas concluyen que los materiales alternativos (de contenido reciclado son mejores que los tradicionales, porque reducen la contaminación del aire al interior de los edificios. This report presents an evaluation of emissions from indoor building materials that may cause health damage to the people who occupy the building, since these materials emit toxic chemicals into the air and indoor surfaces. This report presents a case study which evaluates Gypsum Boards, frequently used in the construction of dividing walls and ceilings. The experimental part of this report is based on a three-dimensional space that simulates a

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

    Science.gov (United States)

    Stolarska, Agata; Garbalińska, Halina

    2017-05-01

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

  10. Development of an Assessment Method for Building Materials Under Euratom Scope.

    Science.gov (United States)

    de With, Govert

    2017-11-01

    In 2013, the European Commission published its basic safety standards for protection against the dangers arising from exposure to ionizing radiation (Council Directive 2013/59/Euratom)-also known as EU-BSS. As a result, the use of raw materials with potentially elevated activity concentrations such as fly ash, phosphogypsum, and slags will now fall under EU-BSS scope when applied in building materials. In light of this new policy, a variety of tools are available to assess compliance with the 1-mSv y reference level for building materials. At the heart of these tools is a gamma-spectrometric determination of the naturally occurring radionuclides Ra, Th, and K in the material of concern. As a large number of construction products contain a certain amount of the raw material that falls under the scope of the EU regulation, this policy will lead to substantial measurement of building materials that pose little radiation risk. For this reason, a method is developed to enable assessment against the 1-mSv value not on the basis of gamma-spectrometric analysis but rather based on the product's material composition. The proposed method prescribes a maximum permitted content of raw materials with potentially elevated activity concentrations in terms of a weight percentage of the end product, where the raw materials of concern are defined as those listed in Annex XIII of the EU-BSS. The permitted content is a function of the product's surface density. Therefore, a product with a low surface density of up to 25 kg m can consist of nearly 100% raw materials with potentially elevated activity concentrations, and this percentage drops to around 15% for products with a surface density of around 500 kg m. Building materials that comply with these requirements on product composition are exempt from testing, while products that do not comply must perform regular gamma-spectrometric analysis. A full validation and testing of the method is provided. In addition, the paper discusses

  11. 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.

  12. 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

  13. The Influence of the Indoor Air Quality of the Microclimate Box on the Material Degradation of Historic Objects

    NARCIS (Netherlands)

    Groves, R.M.

    2016-01-01


    The paper gives an assessment of the Indoor Air Quality (IAQ) within a microclimate box and its influence on the material degradation. IAQ is concerned with maintaining acceptable temperature, humidity and oxygen levels and low pollutant levels in the rooms, cabinets or other enclosed spaces,

  14. SEM-EDX Study of the Degradation Process of Two Xenograft Materials Used in Sinus Lift Procedures

    Directory of Open Access Journals (Sweden)

    María Piedad Ramírez Fernández

    2017-05-01

    Full Text Available Some studies have demonstrated that in vivo degradation processes are influenced by the material’s physico-chemical properties. The present study compares two hydroxyapatites manufactured on an industrial scale, deproteinized at low and high temperatures, and how physico-chemical properties can influence the mineral degradation process of material performance in bone biopsies retrieved six months after maxillary sinus augmentation. Residual biomaterial particles were examined by field scanning electron microscopy (SEM and energy dispersive X-ray spectroscopy (EDX to determine the composition and degree of degradation of the bone graft substitute material. According to the EDX analysis, the Ca/P ratio significantly lowered in the residual biomaterial (1.08 ± 0.32 compared to the initial composition (2.22 ± 0.08 for the low-temperature sintered group, which also presented high porosity, low crystallinity, low density, a large surface area, poor stability, and a high resorption rate compared to the high-temperature sintered material. This demonstrates that variations in the physico-chemical properties of bone substitute material clearly influence the degradation process. Further studies are needed to determine whether the resorption of deproteinized bone particles proceeds slowly enough to allow sufficient time for bone maturation to occur.

  15. 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.

  16. 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.

  17. Final report for the designed synthesis of controlled degradative materials LDRD

    Energy Technology Data Exchange (ETDEWEB)

    LOY,DOUGLAS A.; ULIBARRI,TAMARA A.; CURRO,JOHN G.; SAUNDERS,R.; DERZON,DORA K.; GUESS,TOMMY R.; BAUGHER,B.M.

    2000-02-01

    The main goal of this research was to develop degradable systems either by developing weaklink-containing polymers or identifying commercial polymeric systems which are easily degraded. In both cases, the degradation method involves environmentally friendly chemistries. The weaklinks are easily degradable fragments which are introduced either randomly or regularly in the polymer backbone or as crosslinking sites to make high molecular weight systems via branching. The authors targeted three general application areas: (1) non-lethal deterrents, (2) removable encapsulants, and (3) readily recyclable/environmentally friendly polymers for structural and thin film applications.

  18. Preparation of Diatomite Supported Nano Zinc Oxide Composite Photocatalytic Material and Study on its Formaldehyde Degradation

    Science.gov (United States)

    Xiao, Liguang; Pang, Bo

    2017-09-01

    This experiment used zinc nitrate as precursor, ethanol as solvent and polyethylene glycol as dispersant, diatomite as carrier, diatomite loaded nano Zinc Oxide was prepared by sol-gel method, in addition, the formaldehyde degradation was studied by two kinds of experimental methods: preparation and loading, preparation and post loading, The samples were characterized by SEM, XRD, BET and IR. Experimental results showed that: Diatomite based nano Zinc Oxide had a continuous adsorption and degradation of formaldehyde, formaldehyde gas with initial concentration was 0.7mg/m3, after 36h degradation, the concentration reached 0.238mg/m3, the degradation rate reached to 66%.

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

    DEFF Research Database (Denmark)

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

    2012-01-01

    X-ray attenuation measurements are commonly used as a non-destructive method to monitor internal concentration changes of moisture (i.e., moisture content) and other chemical compounds in porous building materials. The technique provides direct measurements of moisture content changes through......, consistent energy) and that interactions between the x-ray photons and the materials (water and porous material) are independent. However, x-ray sources typically used by researchers in this field of study produce x-ray photon beams over a spectrum of energy levels, or polychromatic x-ray photons...... analysis with a composite model consisting of a dry porous material and a thickness of water equivalent to the moisture content of the material. The current formulation of this composite model relies on certain assumptions, including a monochromatic x-ray photon beam source (i.e., x-ray photons of a single...

  20. Numerical analysis of heat, air, and moisture transfers in a wooden building material

    Directory of Open Access Journals (Sweden)

    Mnasri Faiza

    2017-01-01

    Full Text Available The present paper aims to predict the hygrothermal behavior of massive wood panel considered as bio-based building material. In this context, we developed a macroscopic model coupled no linear heat, air, and moisture transfers that incorporates simultaneously the effect of thermal diffusion and infiltration phenomenon on the building material. The model inputs parameters were evaluated experimentally according to the recognized standards of material’s characterization. Therefore, numerous series of hygrothermal calculation were carried out on the 1-D and 2-D configuration in order to assess the dimensionless effect on such wooden material. Two types of boundary conditions were considered and examined. The first are at the material scale of wood drying process. The second type of conditions is at the wall scale, where the conditions of the building ambiance are considered. Moreover, the model sensitivity to the driving potentials coupling and to the parameters variability was considered and examined. It has been found that the coupling in the model had a remarkable impact on both kinetics of temperature and moisture content.

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

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, C.E

    1999-08-01

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

  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. 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

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

    Science.gov (United States)

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

    2014-03-01

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

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

    Science.gov (United States)

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

    2017-02-01

    To fulfill national and international fire safety standards, flame retardants (FRs) are being added to a wide range of consumer products and building materials consisting of flammable materials like plastic, wood and textiles. While the FR composition of some products and materials has been identified in recent years, the limited global coverage of the data and the large diversity in consumer products necessitates more information for an overall picture of the FR composition in common products/materials. To address this issue, 137 individual samples of various consumer products, building materials and wastes were collected. To identify and characterize potential sources of FRs in indoor environment, all samples were analyzed for content of polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDDs) and novel flame retardants (NFRs). The most frequently detected were HBCDDs (85%), with the highest median concentration of Σ4HBCDDs of 300 mg kg-1 in polystyrenes. The highest median concentration of Σ10PBDEs was found in recycled plastic materials, reaching 4 mg kg-1. The lowest concentrations were observed for NFRs, where the median of Σ12NFRs reached 0.4 mg kg-1 in the group of electrical & electronic equipment wastes. This suggests that for consumer products and building materials that are currently in-use, legacy compounds still contribute to the overall burden of FRs. Additionally, contrasting patterns of FR composition in recycled and virgin plastics, revealed using principle component analysis (PCA), suggest that legacy flame retardants are reentering the market through recycled products, perpetuating the potential for emissions to indoor environments and thus for human exposure. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

    NARCIS (Netherlands)

    Quist, W.J.

    2015-01-01

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

  7. 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)

  8. Thermal characterization of a new effective building material based on clay and olive waste

    Directory of Open Access Journals (Sweden)

    Mohamed Lamrani

    2018-01-01

    Full Text Available The influence of thermophysical properties of wall materials on energy performance and comfort in traditional building was investigated. The clay is the most commonly used sustainable building material. The study looked at the effects of the addition of pomace olive on the thermophysical properties of clay bricks to improve the energy efficiency of this ecological material. An experimental measurement of thermal properties of clay mixed with pomace olive was carried out by using the transient and steady state hot-plate and flash methods. The experimental methods are applied to measure the thermal properties of the composite material. The estimation of these thermal characteristics is based on a one dimensional model and the experimental errors are found less than 3%. The composite samples were prepared with different granular classes and mass fractions of the pomace olive in the mixture. The results show that the density of the new material was not substantially influenced by the size of the pomace olive. However, the thermal conductivity and diffusivity decrease from 0.65 W.m-1.K-1 and 4.21×10-7 m2.s-1 to 0.29 W.m-1.K-1 and 2.47×10-7m2.s-1, respectively, according to the variation of the volume fraction of pomace olive from 0 (pure clay to 71% showing that the olive pomace can be used as effective secondary raw materials in the making of clay bricks.

  9. Towards the development of performance based guidelines for using Phase Change Materials in lightweight buildings

    Science.gov (United States)

    Poudel, Niraj

    Incorporating Phase Change Materials (PCMs) in construction materials can increase the thermal mass of a building. With this increase in thermal mass, PCMs are known to reduce the heating and cooling loads of a building significantly. During the past 10 years, studies have estimated potential reduction of energy consumption of buildings between 10 and 30 percent. This wide range is due to the large number of parameters that effect energy consumption and make the process of selecting the optimal type and amount of PCM challenging. In fact, extensive engineering studies are generally necessary to determine the practicality of PCM in any specific case. As a result, architects and engineers are reluctant to use PCM because of the lack of such a comprehensive study. In the United States, eight climate zones are identified on the basis of annual degree heating and degree cooling days. For a given building in a given climate, there exists an optimal melting temperature and enthalpy that can reduce the energy consumption and the payback period. In this research, the optimal properties of PCM boards are determined for all 15 representative cities. Additional topics discussed in this research are the sensitivity of the optimal properties of PCM and the effect of the average cost of energy on the selection of PCM. The effect of six independent variables on the performance of PCM boards is presented in detail and the climate types where PCM boards perform optimally are narrowed down. In addition, a new procedure is presented to study the temporal and directional melting and solidifying trend of the PCM placed in buildings. The energy consumption and hourly data for the PCM enhanced buildings are determined numerically using the Department of Energy software EnergyPlus, which calculates the energy consumption for heating and cooling a building under any climate and operation schedule. The software is run on a computer cluster for a wide range of properties from which the

  10. Safety distance for preventing hot particle ignition of building insulation materials

    Directory of Open Access Journals (Sweden)

    Jiayun Song

    2014-01-01

    Full Text Available Trajectories of flying hot particles were predicted in this work, and the temperatures during the movement were also calculated. Once the particle temperature decreased to the critical temperature for a hot particle to ignite building insulation materials, which was predicted by hot-spot ignition theory, the distance particle traveled was determined as the minimum safety distance for preventing the ignition of building insulation materials by hot particles. The results showed that for sphere aluminum particles with the same initial velocities and diameters, the horizontal and vertical distances traveled by particles with higher initial temperatures were higher. Smaller particles traveled farther when other conditions were the same. The critical temperature for an aluminum particle to ignite rigid polyurethane foam increased rapidly with the decrease of particle diameter. The horizontal and vertical safety distances were closely related to the initial temperature, diameter and initial velocity of particles. These results could help update the safety provision of firework display.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-02-15

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

  12. The potential for bioaugmentation of sand filter materials from waterworks using bacterial cultures degrading 4-chloro-2-methylphenoxyacetic acid.

    Science.gov (United States)

    Krüger, Urse S; Johnsen, Anders R; Burmølle, Mette; Aamand, Jens; Sørensen, Sebastian R

    2015-02-01

    The herbicide 4-chloro-2-methylphenoxyacetic acid (MCPA) is found frequently in Danish groundwater in concentrations exceeding the EU threshold limit of 0.1 µg L(-1) . Groundwater is used for drinking water, and one potential remediation strategy is bioaugmentation using inoculation of sand filters at affected waterworks with degrader bacteria. Numerous bacteria degrading phenoxyacetic acid herbicide have previously been isolated, and they may be candidates for bioaugmentation processes. Designing the optimum inoculum, however, requires knowledge of the capacity for degrading realistically low herbicide concentrations and the robustness of the bacteria when inoculated into sand filter materials. Testing a range of different MCPA-mineralising bacterial combinations, using a high-throughput microplate radiorespirometric mineralisation assay, highlighted three efficient cocultures for mineralising low MCPA concentrations. Cocultures demonstrating a shorter time delay before initiation of (14) C-ring-labelled MCPA mineralisation to (14) CO2 , and a more extensive mineralisation of MCPA, compared with those of single strains, were found. When inoculated into different sand filter materials, the coculture effect was diminished, but several single strains enhanced MCPA mineralisation significantly at low MCPA concentrations. This study shows that an increase in the potential for mineralisation of low herbicide concentrations in sand filter materials can be achieved by inoculating with bacterial degrader cultures. © 2014 Society of Chemical Industry. © 2014 Society of Chemical Industry.

  13. Bioresorbable Fe-Mn and Fe-Mn-HA Materials for Orthopedic Implantation: Enhancing Degradation through Porosity Control.

    Science.gov (United States)

    Heiden, Michael; Nauman, Eric; Stanciu, Lia

    2017-07-01

    Resorbable, porous iron-manganese-hydroxyapatite biocomposites with suitable degradation rates for orthopedic applications are prepared using salt-leaching for the first time. These transient biomaterials have the potential to replace inert, permanent implants that can suffer from long-term complications, or have to be surgically removed, leaving an unfavorable void. Fe30Mn-10HA materials are newly developed to address inadequate resorption rates of degradable materials proposed for orthopedic environments in the past. In this study, controllable porosities with 300 µm diameter pores are introduced into Fe30Mn alloys and Fe30Mn-10HA composites, which enhance tissue ingrowth. For the composites, a Ca2 Mn7 O14 phase generated within the Fe30Mn matrix during the sintering process greatly increases degradability. The combination of this second phase and added porosity is found to contribute to increased bone-like apatite layer formation, mouse bone marrow mesenchymal stem cell attachment, and reduction of detrimental oxide layer flaking. Remarkably, after thirty days in vitro, there is a significant increase in degradation up to 0.82 ± 0.04 mm per year for 30 wt% porous Fe30Mn-10HA biocomposites, compared to 0.02 ± 0.00 mm per year for traditional nonporous Fe30Mn, thereby increasing the viability of these materials for future clinical studies. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Investigation of possibility of recovery nonferrous metals and producing building materials from copper-nickel smelterslag

    Directory of Open Access Journals (Sweden)

    Svetlov A.V.

    2015-06-01

    Full Text Available Pelletized slag of copper-nickel smelter ("Pechenganikel" combine, "Kola MMC" JSC has been investigated as a potential technogenic deposit. It has been shown that nonferrous metals can be re-extracted from slag using flotation. The work presents the results of laboratory simulation of heap leaching of non-ferrous metals. Ceramic building materials from slag-based feed have been produced and their main properties have been studied

  15. DETERMINATION OF THERMAL RESPONSE OF CARRARA AND SNEZNIKOVSKY MARBLE USED AS A BUILDING MATERIALS

    Directory of Open Access Journals (Sweden)

    Veronika Petráňová

    2016-02-01

    Full Text Available Physical weathering of marble, widely used as a cladding material on buildings, is one of the most common damaging mechanism caused by anisotropic thermal expansion of calcite grains. The extent of marble deterioration depends mainly on stone fabric and texture. Dry cuboids of Carrara marble and marble from Dolni Morava quarry were subjected to microscopic analysis and thermal cycling, to determine the thermal expansion related to stone fabric and predominant lattice orientation of grains (i.e. texture.

  16. Evaluating the effect of increasing ceramic content on the mechanical properties, material microstructure and degradation of selective laser sintered polycaprolactone/β-tricalcium phosphate materials.

    Science.gov (United States)

    Doyle, Heather; Lohfeld, Stefan; McHugh, Peter

    2015-08-01

    Orthopaedic scaffold materials were fabricated from polycaprolactone (PCL) and composite PCL-β-tricalcium phosphate (PCL/β-TCP) powders using selective laser sintering (SLS). Incorporating β-TCP particles is desirable to promote osteogenesis. The effects of increasing β-TCP content on the material's mechanical properties and microstructure were evaluated. The wt% of β-TCP and PCL particle sizes were found to influence material microstructure and mechanical properties, with increasing ceramic content causing a small but significant increase in stiffness but significant reductions in strength. Degradation of materials was achieved using accelerated ageing methods. The influence of β-TCP content on degradation at 7 weeks was evaluated through changes in mechanical properties and microstructure, and the ceramic particles were found to reduce elastic modulus and increase strength. The results of this study highlight the influence of ceramic content on mechanical properties and degradation behaviour of PCL/β-TCP SLS materials, and indicate that these changes must be considered in the design of scaffolds for critical-sized defects. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.

  17. Thermal Insulating Properties of Straw-Filled Environmentally Friendly Building Materials

    Science.gov (United States)

    Petkova-Slipets, Rositsa; Zlateva, Penka

    2017-06-01

    The paper presents results of a research for determination of a few general thermal-physical properties of environmentally friendly building materials made by clay, sand and straw. The aim of this study is to establish their heat insulating and energy-efficient capacity. All specific measurements were carried out by using the newest generation thermal conductivity analyser Mathis TCi. The results showed that the studied composite materials are good thermal insulators with thermal conductivity less than 0.5 W/m.K, which depends on the straw amount. Even less than 0.5 wt.% straw reflects on the insulating properties by decreasing the thermal conductivity coefficient with nearly 50 %.

  18. Analytical study of radionuclide concentration and radon exhalation rate in market available building materials of Ramsar

    Science.gov (United States)

    Bavarnegin, Elham; Vahabi-moghaddam, Masoud; Babakhani, Asad; Fathabadi, Nasrin

    2012-07-01

    Samples of structural and covering market available building materials from Ramsar, a northern city of Iran, were analyzed for their radon exhalation rate using an active radon gas analyzer with an emanation container. The radon exhalation rate varied from below the minimum detection limit of 0.01 to 0.31 Bq·m-2·h-1 with an average of 0.08 Bq·m-2·h-1. The 226Ra, 232Th, and 40K contents were also measured using a high resolution HPGe gamma-ray spectrometer system. The radionuclides contents varied from below the minimum detectable activity up to 73.5, 169, and 1,350 Bq.kg-1, with the average value of 16 ± 6, 25 ± 11, and 280 ± 101 Bq.kg-1, respectively. It was concluded from the results that some granite samples along with the block sample were the main source of radon exhalation rate, and the mean values of 226Ra, 232Th, and 40K in building material samples are below the world average values. Therefore, the use of these market available building materials in construction of Ramsar dwellings is considered to be safe for human habitation.

  19. Phase Change Materials as a solution to improve energy efficiency in Portuguese residential buildings

    Science.gov (United States)

    Araújo, C.; Pinheiro, A.; Castro, M. F.; Bragança, L.

    2017-10-01

    The buildings sector contributes to 30% of annual greenhouse gas emissions and consumes about 40% of energy. However, this consumption can be reduced by between 30% and 80% through commercially available technologies. The consumption of energy in the dwellings is mostly associated with the heating and cooling of the interior environment. One solution to reduce these consumptions is the implementation of technologies and Phase Change Materials (PCMs) for Thermal Energy Storage (TES). So, the aim of this work is to analyse the advantages, in terms of decreasing energy consumption, associated with the application of PCMs in Portuguese residential buildings. For this, eight PCMs with different melting ranges were analysed. These materials were analysed through a dynamic simulation performed with EnergyPlus software. The results achieved, showed that the materials studied allow to reduce up to 13% of the heating needs and up to 92% of the cooling needs of a building located in the North of Portugal, at an altitude higher than 100m.

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

    Science.gov (United States)

    Bala, Pankaj; Kumar, Vinod; Mehra, Rohit

    2017-03-01

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

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

    Science.gov (United States)

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

    2000-06-01

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

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

    Directory of Open Access Journals (Sweden)

    Spišáková Marcela

    2015-11-01

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

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

    Directory of Open Access Journals (Sweden)

    Girish Kumar

    2015-01-01

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

  4. Determining Radium-226 concentration from Radon-222 emanation in building materials: a theoretical model

    Energy Technology Data Exchange (ETDEWEB)

    Barreto, Rafael C.; Perna, Allan F.N.; Narloch, Danielle C.; Del Claro, Flavia; Correa, Janine N.; Paschuk, Sergei A., E-mail: baarreth@gmail.com, E-mail: allan_perna@hotmail.com, E-mail: daninarloch@hotmail.com, E-mail: aviadelclaro@gmail.com, E-mail: janine_nicolosi@hotmail.com, E-mail: spaschuk@gmail.com [Universidade Tecnologica Federal do Parana (UTFPR), Curitiba, PR (Brazil). Departamento Academico de Fisica e Departamento Academico de Construcao Civil

    2017-07-01

    It was developed an improved theoretical model capable to estimate the radium concentration in building materials solely measuring the radon-222 concentration in a con ned atmosphere. This non-destructive technique is not limited by the size of the samples, and it intrinsically includes back diffusion. The resulting equation provides the exact solution for the concentration of radon-222 as a function of time and distance in one dimension. The effective concentration of radium-226 is a fit parameter of this equation. In order to reduce its complexity, this equation was simplified considering two cases: low diffusion in the building material compared to the air, and a building material initially saturated with radon-222. These simplified versions of the exact one dimension solution were used to t experimental data. Radon-222 concentration was continuously measured for twelve days with an AlphaGUARD{sup TM} detector, located at the Laboratory of Applied Nuclear Physics at Universidade Tecnologica Federal do Parana (UTFPR). This model was applied to two different materials: cement mortar and concrete, which results were respectively (15:7 ±8:3) Bq=kg and (10:5±2:4) Bq=kg for the radium-226 effective concentration. This estimation was confronted with the direct measurements of radium in the same materials (same sources) using gamma-ray spectrometry, fulfilled at Centro de Desenvolvimento da Tecnologia Nuclear (CDTN), which results were respectively (13:81±0:23) Bq=kg and (12:61±0:22) Bq=kg. (author)

  5. 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.

  6. Radioactivity assessment of some building materials from Little Poland Region; Analiza promieniotworczosci niektorych materialow budowlanych z obszaru Malopolski

    Energy Technology Data Exchange (ETDEWEB)

    Bogacz, J.; Cywicka-Jakiel, T.; Mazur, J.; Loskiewicz, J.; Swakon, J.; Tracz, G. [Institute of Nuclear Physics, Cracow (Poland)

    1994-12-31

    In the paper are presented the results of building materials analysis connected with radiation protection. The concentration of natural radioactive elements (K, U, Th), and the values of f{sup 1} and f{sup 2} coefficients are measured for these materials. The values for ceramic building materials and for cellular concretes are composed. The utility of f{sup 2} parameter is unformally discussed. (author). 9 refs, 12 figs, 3 tabs.

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

    Directory of Open Access Journals (Sweden)

    Yoon-Bok Seong

    2013-10-01

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

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

    Directory of Open Access Journals (Sweden)

    Martin Butson

    2016-01-01

    Full Text Available Total body irradiation (TBI treatments are mainly used in a preparative regimen for hematopoietic stem cell (or bone marrow transplantation. Our standard clinical regimen is a 12 Gy/6 fraction bi-daily technique using 6MV X-rays at a large extended source to surface distance (SSD. This work investigates and quantifies the dose build-up characteristics and thus the requirements for bolus used for in vivo dosimetry for TBI applications. Percentage dose build-up characteristics of photon beams have been investigated at large extended SSDs using ionization chambers and Gafchromic film. Open field measurements at different field sizes and with differing scatter conditions such as the introduction of standard Perspex scattering plates at different distances to the measurement point were made in an effort to determine the required bolus/build-up material required for accurate determination of applied dose. Percentage surface dose values measured for open fields at 300 cm SSD were found to range from 20% up to 65.5% for fields 5 cm × 5 cm to 40 cm × 40 cm, respectively. With the introduction of 1 cm Perspex scattering plates used in TBI treatments, the surface dose values increased up to 83–90% (93–97% at 1 mm depth, depending on the position of the Perspex scattering plate compared to the measurement point. Our work showed that at least 5 mm water equivalent bolus/scatter material should be placed over the EBT3 film for accurate dose assessment for TBI treatments. Results also show that a small but measurable decrease in measured dose occurred with 5 mm water equivalent thick bolus material of areas '3 cm2. As such, we recommend that 3 cm × 3 cm × 5 mm bolus build-up is the smallest size that should be placed over EBT3 Gafchromic film when used for accurate in vivo dosimetry for TBI applications.

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

    Science.gov (United States)

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

    2016-01-01

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

  10. Materials produced from plant biomass: part II: evaluation of crystallinity and degradation kinetics of cellulose

    Directory of Open Access Journals (Sweden)

    Matheus Poletto

    2012-06-01

    Full Text Available In this study Eucalyptus grandis (CEG and Pinus taeda (CPT cellulose fibers obtained from kraft and sulfite pulping process, respectively, were characterized using Fourier transform infrared (FTIR spectroscopy and thermogravimetry (TGA. The degradation kinetic parameters were determined by TGA using Coats and Redfern method. FTIR results showed that CPT presented a more ordered structure with higher crystallinity than CEG. Thermogravimetric results showed that CPT had a higher thermal stability than CEG. The kinetic results revel that for CEG the degradation mechanism occurs mainly by random nucleation, although phase boundary controlled reactions also occurs while for CPT the degradation process is more related with phase boundary controlled reactions. Results demonstrated that differences between thermal stability and degradation mechanisms might be associated with differences in the cellulose crystalline structure probably caused by different pulping processes used for obtaining the cellulose fibers.

  11. Ice crystallization in porous building materials: assessing damage using real-time 3D monitoring

    Science.gov (United States)

    Deprez, Maxim; De Kock, Tim; De Schutter, Geert; Cnudde, Veerle

    2017-04-01

    Frost action is one of the main causes of deterioration of porous building materials in regions at middle to high latitudes. Damage will occur when the internal stresses due to ice formation become larger than the strength of the material. Hence, the sensitivity of the material to frost damage is partly defined by the structure of the solid body. On the other hand, the size, shape and interconnection of pores manages the water distribution in the building material and, therefore, the characteristics of the pore space control potential to form ice crystals (Ruedrich et al., 2011). In order to assess the damage to building materials by ice crystallization, lot of effort was put into identifying the mechanisms behind the stress build up. First of all, volumetric expansion of 9% (Hirschwald, 1908) during the transition of water to ice should be mentioned. Under natural circumstances, however, water saturation degrees within natural rocks or concrete cannot reach a damaging value. Therefore, linear growth pressure (Scherer, 1999), as well as several mechanisms triggered by water redistribution during freezing (Powers and Helmuth, 1953; Everett, 1961) are more likely responsible for damage due to freezing. Nevertheless, these theories are based on indirect observations and models and, thus, direct evidence that reveals the exact damage mechanism under certain conditions is still lacking. To obtain this proof, in-situ information needs to be acquired while a freezing process is performed. X-ray computed tomography has proven to be of great value in material research. Recent advances at the Ghent University Centre for Tomography (UGCT) have already allowed to dynamically 3D image crack growth in natural rock during freeze-thaw cycles (De Kock et al., 2015). A great potential to evaluate the different stress build-up mechanisms can be found in this imaging technique consequently. It is required to cover a range of materials with different petrophysical properties to achieve

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

    Science.gov (United States)

    Rydz, Joanna; Sikorska, Wanda; Kyulavska, Mariya; Christova, Darinka

    2014-01-01

    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 view of the potential applications in various fields. PMID:25551604

  13. Review of the use of phase change materials (PCMs in buildings with reinforced concrete structures

    Directory of Open Access Journals (Sweden)

    Pons, O.

    2014-09-01

    Full Text Available Phase change materials are capable of storing and releasing energy in the form of heat in determined temperature ranges, so to increase a building’s thermal inertia, stabilize its indoor temperatures and reduce its energetic demand. Therefore, if we used these materials we could have more energetically efficient buildings. Nevertheless, are these materials most appropriate to be used in buildings? Could the incorporation of phase change materials in buildings with concrete structures be generalized? This article aims to carry out a review of these phase change materials from construction professionals’ points of view, study their applications for buildings with reinforced concrete structures and the key points for these applications, draw conclusions and provide recommendations useful for all professionals within the sector who are considering the application of these materials.Los materiales de cambio de fase son capaces de almacenar y liberar energía en forma de calor en un determinando rango de temperaturas, y así aumentar la inercia térmica de un edificio, estabilizar las temperaturas en el interior y reducir la demanda energética. En consecuencia, si utilizáramos estos materiales podríamos tener un parque de edificios más eficientes energéticamente. No obstante, ¿estos materiales son apropiados para usarse en edificios? ¿Se podría generalizar la incorporación de materiales de cambio de fase en edificios con estructuras de hormigón? Este artículo tiene como objetivos hacer una revisión del estado del arte de estos materiales de cambio de fase desde el punto de vista de los profesionales de la construcción, estudiar las aplicaciones en edificios con estructuras de hormigón armado y los puntos clave para estas aplicaciones, extraer conclusiones y recomendaciones útiles para los profesionales del sector que se planteen la utilización de estos materiales.

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

    Science.gov (United States)

    Kumar, Girish; Shivrayan, Amit

    2015-01-01

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

  15. Composite Building Materials: Thermal and Mechanical Performances of Samples Realized with Hay and Natural Resins

    Directory of Open Access Journals (Sweden)

    Maria La Gennusa

    2017-03-01

    Full Text Available Recent years have seen an increasing public interest in issues related to energy saving and environmental pollution reduction in the building sector. As a result, many directives have been issued, the most important being the Directive 2010/31/EU (EPBD Recast on the energy performance of buildings, which requires that “Member States shall ensure that by 31 December 2020 all new buildings are nearly zero-energy buildings”. This goal can be obtained not only by reducing energy demand for heating and cooling, but also, for example, by improving building envelope performances. In this work, a first analysis of the thermal and structural behaviour of a biocomposite material, constituted by a natural resin (rosin and vegetal fibres (hay, has been performed, with particular attention to the share of fibres and the granulometry in the mixture. The biocomposite has shown both good insulation properties and mechanical resistance. However, the results show that further analyses should be performed on the optimisation of the samples’ preparation process.

  16. Data Collection Handbook to Support Modeling Impacts of Radioactive Material in Soil and Building Structures

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Charley [Argonne National Lab. (ANL), Argonne, IL (United States); Kamboj, Sunita [Argonne National Lab. (ANL), Argonne, IL (United States); Wang, Cheng [Argonne National Lab. (ANL), Argonne, IL (United States); Cheng, Jing-Jy [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-09-01

    This handbook is an update of the 1993 version of the Data Collection Handbook and the Radionuclide Transfer Factors Report to support modeling the impact of radioactive material in soil. Many new parameters have been added to the RESRAD Family of Codes, and new measurement methodologies are available. A detailed review of available parameter databases was conducted in preparation of this new handbook. This handbook is a companion document to the user manuals when using the RESRAD (onsite) and RESRAD-OFFSITE code. It can also be used for RESRAD-BUILD code because some of the building-related parameters are included in this handbook. The RESRAD (onsite) has been developed for implementing U.S. Department of Energy Residual Radioactive Material Guidelines. Hydrogeological, meteorological, geochemical, geometrical (size, area, depth), crops and livestock, human intake, source characteristic, and building characteristic parameters are used in the RESRAD (onsite) code. The RESRAD-OFFSITE code is an extension of the RESRAD (onsite) code and can also model the transport of radionuclides to locations outside the footprint of the primary contamination. This handbook discusses parameter definitions, typical ranges, variations, and measurement methodologies. It also provides references for sources of additional information. Although this handbook was developed primarily to support the application of RESRAD Family of Codes, the discussions and values are valid for use of other pathway analysis models and codes.

  17. Study on the Influence of Building Materials on Indoor Pollutants and Pollution Sources

    Science.gov (United States)

    Wang, Yao

    2018-01-01

    The paper summarizes the achievements and problems of indoor air quality research at home and abroad. The pollutants and pollution sources in the room are analyzed systematically. The types of building materials and pollutants are also discussed. The physical and chemical properties and health effects of main pollutants were analyzed and studied. According to the principle of mass balance, the basic mathematical model of indoor air quality is established. Considering the release rate of pollutants and indoor ventilation, a mathematical model for predicting the concentration of indoor air pollutants is derived. The model can be used to analyze and describe the variation of pollutant concentration in indoor air, and to predict and calculate the concentration of pollutants in indoor air at a certain time. The results show that the mathematical model established in this study can be used to analyze and predict the variation law of pollutant concentration in indoor air. The evaluation model can be used to evaluate the impact of indoor air quality and evaluation of current situation. Especially in the process of building and interior decoration, through pre-evaluation, it can provide reliable design parameters for selecting building materials and determining ventilation volume.

  18. Phosphogypsum recycling in the building materials industry: assessment of the radon exhalation rate.

    Science.gov (United States)

    Campos, M P; Costa, L J P; Nisti, M B; Mazzilli, B P

    2017-06-01

    Phosphogypsum can be classified as a Naturally Occurring Radioactive Material (NORM) residue of the phosphate fertilizer industry. One of the main environmental concerns of its use as building material is the radon exhalation. The aim of this study is to measure the radon exhalation rate from plates and bricks manufactured with phosphogypsum from three installations of the main Brazilian producer, Vale Fertilizantes, in order to evaluate the additional health risk to dwellers. A simple and reliable accumulator method involving a PVC pipe sealed with a PVC pipe cover commercially available with CR-39 radon detector into a diffusion chamber was used for measuring radon exhalation rate from phosphogypsum made plates and bricks. The radon exhalation rate from plates varied from 0.19 ± 0.06 Bq m(-2) h(-1), for phosphogypsum from Bunge Fertilizers, from 1.3 ± 0.3 Bq m(-2) h(-1), for phosphogypsum from Ultrafertil. As for the bricks, the results ranged from 0.11 ± 0.01 Bq m(-2) h(-1), for phosphogypsum from Bunge Fertilizers, to 1.2 ± 0.3 Bq m(-2) h(-1), for phosphogypsum from Ultrafertil. The results obtained in this study for the radon exhalation rate from phosphogypsum plates and bricks are of the same order of magnitude than those from ordinary building materials. So, it can be concluded that the recycling of phosphogypsum as building material is a safe practice, since no additional health risk is expected from the radiological point of view. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Green Sharing: The Proposed Criteria in Green Building Standards to Promote the Usage of Natural Handicrafts in Building Materials

    Directory of Open Access Journals (Sweden)

    Krasae-In Aracha

    2016-01-01

    Full Text Available Sustainable development has been a great challenge to the building and construction industry for decades. There have been many initiatives and attempts to create sustainability for the industry through the concept of the Green Building certificate in order to reduce the impact to environment and society while promoting better living conditions of the people involved in the project. This paper aims to examine all three aspects of sustainability; economy, environment and society, in the building and construction industry by proposing new criteria for the green building certificate. This will create opportunities for the community based handicraft building products to be specified and purchased to be used in the modern building and construction industry and share the economic value to the community.

  20. Monitoring of Water Content in Building Materials Using a Wireless Passive Sensor

    Directory of Open Access Journals (Sweden)

    Goran Stojanović

    2010-04-01

    Full Text Available This paper describes an innovative design of a wireless, passive LC sensor and its application for monitoring of water content in building materials. The sensor was embedded in test material samples so that the internal water content of the samples could be measured with an antenna by tracking the changes in the sensor’s resonant frequency. Since the dielectric constant of water was much higher compared with that of the test samples, the presence of water in the samples increased the capacitance of the LC circuit, thus decreasing the sensor’s resonant frequency. The sensor is made up of a printed circuit board in one metal layer and water content has been determined for clay brick and autoclaved aerated concrete block, both widely used construction materials. Measurements were conducted at room temperature using a HP-4194A Impedance/Gain-Phase Analyzer instrument.

  1. Characterization of magnetic material in the mound-building termite Macrotermes gilvus in Southeast Asia

    Science.gov (United States)

    Esa, Mohammad Faris Mohammad; Rahim, Faszly; Hassan, Ibrahim Haji; Hanifah, Sharina Abu

    2015-09-01

    Magnetic material such as magnetite are known as particles that respond to external magnetic field with their ferromagnetic properties as they are believed contribute to in responding to the geomagnetic field. These particles are used by terrestrial animals such as termites for navigation and orientation. Since our earth react as giant magnetic bar, the magnitude of this magnetic field present by intensity and direction (inclination and direction). The magnetic properties and presence of magnetite in termites Macrotermes gilvus, common mound-building termite were tested. M. gilvus termites was tested with a Vibrating Sample Magnetometer VSM to determine the magnetic properties of specimen. The crushed body sample was characterized with X-Ray Diffraction XRD to show the existent of magnetic material (magnetite) in the specimens. Results from VSM indicate that M. gilvus has diamagnetism properties. The characterization by XRD shows the existent of magnetic material in our specimen in low concentration.

  2. Verification of Joule heat evolution model for silicate building materials with electrically conductive admixtures

    Science.gov (United States)

    Fiala, Lukáš; Maděra, Jiří; Černý, Robert

    2017-07-01

    Silicate building materials naturally exhibit electrically non-conductive behavior. However, a sufficient amount of electrically conductive admixtures leads to a significant increase of the electrical conductivity. This fact can be utilized in several practical ways, such as for development of self-sensing, electromagnetically-shielding or self-heating materials. In this paper, self-heating ability of chosen silicate material was tested and previously developed heating model was verified by means of comparison of calculated temperature evolution in time data with those experimentally determined by thermocouples placed on lateral sides. Sufficiently electrically conductive mixture with carbon black (CB) in amount of 8.89 % was used for DC experiment. Theoretical data were obtained by subsequent FEM calculations conducted on 3D model of the tested sample.

  3. 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

    a series of adsorption and desorption processes. The data provides clear evidence that the water content – water potential relationship is not only dependent on the process history, but also on the process dynamics. The higher moisture potential gradients were induced, the larger was the deviation between...... 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...... the required material functions, i.e. the moisture storage characteristic and the liquid water conductivity, from measured basic properties. The current state of the art in material modelling as well as the corresponding transport theory implies that the moisture transport function is unique...

  4. Evaluation of Ultrasonic and Thermal Nondestructive Evaluation for the Characterization of Aging Degradation in Braided Composite Materials

    Science.gov (United States)

    Martin, Richard E.

    2010-01-01

    This paper examines the ability of traditional nondestructive evaluation (NDE) techniques to measure the degradation of braided polymer composite materials subjected to thermal-humidity cycling to simulate aging. A series of braided composite coupons were examined using immersion ultrasonic and pulsed thermography techniques in the as received condition. These same specimens were then examined following extended thermal-humidity cycling. Results of this examination did not show a significant change in the resulting (NDE) signals.

  5. Assessment of radiation hazards due to natural radioactivity in some building materials used in Egyptian dwellings.

    Science.gov (United States)

    Medhat, M E

    2009-02-01

    Different types of Egyptian building materials from various locations in Cairo and its suburbs have been analysed for natural radioactivity using gamma ray spectrometry. Concentrations of (226)Ra, (232)Th and (40)K were in the ranges of (12 +/- 2.8-65 +/- 6.5), (5 +/- 1.8-60 +/- 6.7) and (159 +/- 3.8-920 +/- 12.7 Bq kg(-1)), respectively. The minimum concentration of (226)Ra, (232)Th and (40)K was found in gravel samples, whereas the maximum in granite samples. The results are compared with the published data of other countries and with the world average limits. The radiological hazard parameters: radium equivalent activity, gamma index, alpha index, absorbed dose rate and the annual exposure rate, were determined to assess the radiation hazards associated with Egyptian buildings. All studied samples are lower than world average limits.

  6. Titania-alumina aerogel materials for degradation of rhodamine B dye: Impact of particle size of titania

    Science.gov (United States)

    Shrestha, Sunav

    Disposal of pollutants, mainly organic dyes from textile industries are the primary sources of water pollution in developing countries, and often leading to scarcity of clean water. These dyes can undergo further oxidation and form several toxic compounds, which possess threat to the water ecosystem. It is therefore necessary to remove these organics from effluents for a clean environment. Among the various methods, Advanced Oxidation Processes (AOPs) called heterogeneous photocatalysis is considered as an effective method for the removal of organics from water sources. In this regard, a set of titania-alumina (TiO2-Al2O3) mixed oxide materials were prepared by supercritical drying method and investigated towards the degradation of a model pollutant, rhodamine B (RhB). The physico-chemical properties of the synthesized materials were studied in detail using several techniques that include powder X-ray diffraction, nitrogen physisorption, diffuse reflectance spectroscopy, and X-ray photoelectron spectroscopy (XPS). The Electrospray ionization-Mass spectroscopic (ESI-MS) studies were also carried out to confirm the degradation of the RhB by identifying its intermediate products. The results indicate that the particle size of the photoactive species, titania, was the key factor for effective photocatalytic degradation of the RhB dye over the titania-alumina mixed oxide materials.

  7. Application of headspace for research volatile organic compounds emitted from building materials

    Directory of Open Access Journals (Sweden)

    Kultys Beata

    2018-01-01

    Full Text Available Headspace technique and gas chromatography method with mas detector has been used for the determination of volatile organic compounds (VOC emitted from various building and finishing materials, such as sealing foams, mounting strips, paints, varnishes, floor coverings. The tests were carried out for different temperatures (in the temperature range of 60 to 180 °C and the time of heated vials with tested materials inside. These tests were conducted to verify the possibility of use this method of determination the VOC emission. Interpretation of chromatograms and mass spectra allowed to identify the type of compounds emitted from the tested materials and the optimum time and temperature for each type of material was determined. The increase in heating temperature of the samples resulted in increase the type and number of identified compounds: for four materials the increase was in the whole temperature range, for others it was from 90 °C. On the other hand, emission from mineral wool was low in whole temperature range. 30-minutes heating of the samples was sufficient to identify emitted compounds for most of tested materials. Applying a longer time, i.e. 24 hours, significantly increased the sensitivity of the method.

  8. Composition and properties of ceramic heat insulating building materials made ofthe masses of low temperature foaming on the basis of clay raw material

    OpenAIRE

    Selivanov Y.V.; Shiltsina A.D.; Selivanov V.M.; Loginova Y.V.; Korolkova N.N.

    2012-01-01

    Ceramic heat-insulating building materials are the most promising for modern construction. Longlived, bio-resistant and corrosion-resistant, nonhygroscopic and noncombustible, they have the greatest stability of heat engineering properties through time. The combination of these properties is especially important in construction in seismic areas.The article contains the study results of compositions and properties of ceramic heat-insulting building materials of masses on the basis of clay raw ...

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

    Science.gov (United States)

    He, Fupo; Zhang, Jing; Yang, Fanwen; Zhu, Jixiang; Tian, Xiumei; Chen, Xiaoming

    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. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. The influence of rainwater composition on the conservation state of cementitious building materials

    Energy Technology Data Exchange (ETDEWEB)

    Morillas, Héctor, E-mail: hector.morillas@ehu.es [Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country UPV/EHU, P.O. Box 644, 48080 Bilbao, Basque Country (Spain); Marcaida, Iker [Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country UPV/EHU, P.O. Box 644, 48080 Bilbao, Basque Country (Spain); Maguregui, Maite [Department of Analytical Chemistry, Faculty of Pharmacy, University of the Basque Country UPV/EHU, P.O. Box 450, 01080 Vitoria-Gasteiz, Basque Country (Spain); Carrero, Jose Antonio; Madariaga, Juan Manuel [Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country UPV/EHU, P.O. Box 644, 48080 Bilbao, Basque Country (Spain)

    2016-01-15

    Rainwater is one of the main pollution tracers around the world. There are many reasons that can explain the presence of high concentrations of certain hazardous elements (HEs) in the rainwater (traffic, marine port activities, industry, etc.). In this work, rainwater samples were collected at six different locations in the Metropolitan Bilbao (Basque Country, north of Spain) during November 2014. HE concentrations were determined by means of inductively coupled plasma mass spectrometry (ICP-MS) and anions by ion chromatography. The pH and redox potential values on these samples were also assessed. According to the obtained results, different trends along the estuary of Bilbao have been observed. To corroborate some hypothesis, thermodynamic simulations and correlation analyses were also carried out using quantitative data. These trends are closely related to the surrounding pollution and marine influence. Finally, in order to ascertain the influence of the Metropolitan Bilbao rainwater on buildings materials, a recent construction was characterized. Using techniques such as Scanning Electron Microscopy coupled with Energy Dispersive X-Ray Spectroscopy (SEM–EDS) and Raman Spectroscopy, different types of sulfates and nitrates were observed. - Highlights: • Rainwater from six sampling points along Nervion River (Bilbao, Spain) were analyzed. • Ion chromatography, ICP-MS and chemometrics were used for the rainwater analyses. • The interaction between wet depositions and building materials was studied. • Cementitious materials were analyzed using µ-Raman spectroscopy and SEM–EDS.

  11. Characterization study on secondary sewage sludge for replacement in building materials

    Science.gov (United States)

    Kadir, Aeslina Abdul; Sarani, Noor Amira; Aziz, Nurul Sazwana A.; Hamdan, Rafidah; Abdullah, Mohd Mustafa Al Bakri

    2017-09-01

    Recently, environmental issues continually increased since expanded in industrial development and grown in population. Regarding to this activity, it will cause lack management of waste such as solid waste from wastewater treatment plant called sewage sludge. This research presents the characteristic study of sewage sludge, regardless of whether it is appropriate or not to be applied as building materials. The sewage sludge samples were collected from secondary treatment at Senggarang and Perwira under Indah Water Konsortium (IWK) treatment plant. Raw materials were tested with X-ray Fluorescence (XRF) and Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) in order to determine the composition of sewage sludge and heavy metal concentration contains in sewage sludge. From the study, it was found that sewage sludge contained high amount of Silica Oxide (SiO2) with 13.6%, Sulphur Trioxide (SO3) with 12.64% and Iron Oxide (Fe2O3) with 8.7% which is similar in clay. In addition, sewage sludge also high in Iron (Fe) with 276.2 mg/L followed by Zinc (Zn) with concentration 45.41 mg/L which sewage sludge cannot be directly disposed to landfill. Results from this study demonstrated that sewage sludge has high possibility to be reused as alternative building materials such as bricks and have compatible chemical composition with clay.

  12. A Review of the Performance of Buildings Integrated with Phase Change Material: Opportunities for Application in Cold Climate

    OpenAIRE

    Madessa, Habtamu B.

    2014-01-01

    Buildings generally need serious attention in order to reduce global energy consumption and greenhouse gas emissions. Phase Change Materials (PCMs) that change phase just above normal room temperature are a promising means of reducing cooling-energy demand, and improving thermal comfort in buildings. This paper reviews the literature from studies of the thermal performance of different types of PCM and different ways of integrating them into buildings. Based on this review, the paper closes w...

  13. In situ degradation of almond (Prunus dulcis L.) hulls, a potential feed material for ruminants

    OpenAIRE

    JAFARI, SAEID; Alizadeh, Alireza; IMNI, ALI; Meng, Goh Yong; Rajion, Mohamed Ali; EBRAHIMI, Mahdi

    2015-01-01

    The nutritive values of almond hulls (Ahs), alfalfa (ALF), and sugar beet pulp (SBP) were determined using the in situ nylon bag technique. The ruminal dry matter (DM) degradation kinetics of 4 varieties of Ahs were compared with ALF and SBP. The almond varieties tested were Rabbi (RAB), Mamaii (MAM), Shahrud 15 (SH15), and Shokufe (SH). Samples were incubated in triplicate at 0, 4, 8, 12, 16, 24, 48, 72, and 96 h in 3 rumen-fistulated steers. The average total degradability fraction (TDF) of...

  14. Determination of the mechanism and extent of surface degradation in Ni-based cathode materials after repeated electrochemical cycling

    Directory of Open Access Journals (Sweden)

    Sooyeon Hwang

    2016-09-01

    Full Text Available We take advantage of scanning transmission electron microscopy and electron energy loss spectroscopy to investigate the changes in near-surface electronic structure and quantify the degree of local degradation of Ni-based cathode materials with the layered structure (LiNi0.8Mn0.1Co0.1O2 and LiNi0.4Mn0.3Co0.3O2 after 20 cycles of delithiation and lithiation. Reduction of transition metals occurs in the near-surface region of cathode materials: Mn is the major element to be reduced in the case of relatively Mn-rich composition, while reduction of Ni ions is dominant in Ni-rich materials. The valences of Ni and Mn ions are complementary, i.e., when one is reduced, the other is oxidized in order to maintain charge neutrality. The depth of degradation zone is found to be much deeper in Ni-rich materials. This comparative analysis provides important insights needed for the devising of new cathode materials with high capacity as well as long lifetime.

  15. Papercrete brick as an alternate building material to control Environmental Pollution

    Science.gov (United States)

    Sudarsan, J. S.; Ramesh, S.; Jothilingam, M.; Ramasamy, Vishalatchi; Rajan, Rajitha J.

    2017-07-01

    Utilization of concrete in the construction industry is increasing day by day. The increasing demand for concrete in the future is the major issue, for which an alternate option is to find out at a reduced or no additional cost and to reduce the environmental impact due to increase of cement industries that are important ingredient to economic development. It turns out urgent to find out alternate for the partial replacement of concrete and cement, as natural sources of aggregates are becoming exhausted. As large quantity of paper waste is generated from different countries all over the world which causes serious environmental problems, So in this present study abandoned paper waste was used as a partial replacement material in concrete,. Study indicates that 80% of the construction cost of a building was contributed by building material and still millions of people in developing countries like India are not able to afford the cost of construction of house. This study is based on potential use of light weight composite brick as a building material and potential use of paper waste for producing at low-cost. Experimental investigation was carried out to analyse optimization of mix for papercrete bricks depending upon the water absorption, compressive strength and unit weight. Papercrete bricks were prepared out of waste paper, and quarry dust with partial replacement of cement by another industrial by-product Fly Ash in varying proportions of 25%, 40% and 55%. The properties like mechanical strength, standard quality comparisons with the conventional bricks through standard tests like hardness, soundness, fire resistance and Cost-Benefit Analysis were performed and studied. The specimens of dimension 230mm x 110mm x 80mm were subjected to 7 Days and 28 days air curing and sun drying before tests were performed on them. Based on the study it was found that for non-load bearing walls papercrete bricks are best suited.

  16. Human Perception, SBS Sympsoms and Performance of Office Work during Exposure to Air Polluted by Building Materials and Personal Computers

    DEFF Research Database (Denmark)

    Bako-Biro, Zsolt

    The present thesis deals with the impact of polluted air from building materials and personal computers on human perception, Sick Building Syndrome (SBS) symptoms and performance of office work. These effects have been studies in a series of experiments that are described in two different chapters...

  17. 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

  18. Dataset of Atmospheric Environment Publication in 2016, Characterization of organophosphorus flame retardants’ sorption on building materials and consumer products

    Data.gov (United States)

    U.S. Environmental Protection Agency — The data presented in this data file is a product of a journal publication. The dataset contains OPFR sorption concentrations on building materials and consumer...

  19. Analytical model of threshold voltage degradation due to localized charges in gate material engineered Schottky barrier cylindrical GAA MOSFETs

    Science.gov (United States)

    Kumar, Manoj; Haldar, Subhasis; Gupta, Mridula; Gupta, R. S.

    2016-10-01

    The threshold voltage degradation due to the hot carrier induced localized charges (LC) is a major reliability concern for nanoscale Schottky barrier (SB) cylindrical gate all around (GAA) metal-oxide-semiconductor field-effect transistors (MOSFETs). The degradation physics of gate material engineered (GME)-SB-GAA MOSFETs due to LC is still unexplored. An explicit threshold voltage degradation model for GME-SB-GAA-MOSFETs with the incorporation of localized charges (N it) is developed. To accurately model the threshold voltage the minimum channel carrier density has been taken into account. The model renders how +/- LC affects the device subthreshold performance. One-dimensional (1D) Poisson’s and 2D Laplace equations have been solved for two different regions (fresh and damaged) with two different gate metal work-functions. LCs are considered at the drain side with low gate metal work-function as N it is more vulnerable towards the drain. For the reduction of carrier mobility degradation, a lightly doped channel has been considered. The proposed model also includes the effect of barrier height lowering at the metal-semiconductor interface. The developed model results have been verified using numerical simulation data obtained by the ATLAS-3D device simulator and excellent agreement is observed between analytical and simulation results.

  20. Incorporation of bioactive glass in calcium phosphate cement: Material characterization and in vitro degradation

    NARCIS (Netherlands)

    Renno, A.C.; Nejadnik, M.R.; Watering, F.C.J. van de; Crovace, M.C.; Zanotto, E.D.; Hoefnagels, J.P.; Wolke, J.G.C.; Jansen, Jan; Beucken, J.J.J.P van den

    2013-01-01

    Calcium phosphate cements (CPCs) have been widely used as an alternative to biological grafts due to their excellent osteoconductive properties. Although degradation has been improved by using poly(D,L-lactic-co-glycolic) acid (PLGA) microspheres as porogens, the biological performance of CPC/PLGA

  1. 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...

  2. Relationship between anode material, supporting electrolyte and current density during electrochemical degradation of organic compounds in water

    Energy Technology Data Exchange (ETDEWEB)

    Guzmán-Duque, Fernando L. [Grupo de diagnóstico y control de la contaminación, Facultad de ingeniería, Universidad de Antioquia, A.A. 1226, Medellín (Colombia); Palma-Goyes, Ricardo E. [Grupo de Investigación en Remediación Ambiental y Biocatálisis, Instituto de Química, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquía Udea, A.A. 1226, Medellín (Colombia); González, Ignacio [Universidad Autónoma Metropolitana-Iztapalapa, Departamento de Química, Av. San Rafael Atlixco No 186, C.P 09340, México D.F (Mexico); Peñuela, Gustavo [Grupo de diagnóstico y control de la contaminación, Facultad de ingeniería, Universidad de Antioquia, A.A. 1226, Medellín (Colombia); Torres-Palma, Ricardo A., E-mail: rtorres@matematicas.udea.edu.co [Grupo de Investigación en Remediación Ambiental y Biocatálisis, Instituto de Química, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquía Udea, A.A. 1226, Medellín (Colombia)

    2014-08-15

    Highlights: • Pathway and efficiency are linked to the current-electrode–electrolyte interaction. • Unlike BDD, IrO{sub 2} route was independent of current but dependent on the electrolyte. • IrO{sub 2}/SO{sub 4}{sup 2−} and IrO{sub 2}/Cl{sup −} routes were via IrO{sub 3} and chlorine species, respectively. • BDD/SO{sub 4}{sup 2−} and IrO{sub 2}/Cl{sup −} systems were favored at low and high currents, respectively. - Abstract: Taking crystal violet (CV) dye as pollutant model, the electrode, electrolyte and current density (i) relationship for electro-degrading organic molecules is discussed. Boron-doped diamond (BDD) or Iridium dioxide (IrO{sub 2}) used as anode materials were tested with Na{sub 2}SO{sub 4} or NaCl as electrolytes. CV degradation and generated oxidants showed that degradation pathways and efficiency are strongly linked to the current density-electrode–electrolyte interaction. With BDD, the degradation pathway depends on i: If i < the limiting current density (i{sub lim}), CV is mainly degraded by ·OH radicals, whereas if i > i{sub lim}, generated oxidants play a major role in the CV elimination. When IrO{sub 2} was used, CV removal was not dependent on i, but on the electrolyte. Pollutant degradation in Na{sub 2}SO{sub 4} on IrO{sub 2} seems to occur via IrO{sub 3}; however, in the presence of NaCl, degradation was dependent on the chlorinated oxidative species generated. In terms of efficiency, the Na{sub 2}SO{sub 4} electrolyte showed better results than NaCl when BDD anodes were employed. On the contrary, NaCl was superior when combined with IrO{sub 2}. Thus, the IrO{sub 2}/Cl{sup −} and BDD/SO{sub 4}{sup 2−} systems were better at removing the pollutant, being the former the most effective. On the other hand, pollutant degradation with the BDD/SO{sub 4}{sup 2−} and IrO{sub 2}/Cl{sup −} systems is favored at low and high current densities, respectively.

  3. Thermal properties of a new ecological building material / Granular cork embedded in white cement

    Directory of Open Access Journals (Sweden)

    Cherki Abou-bakr

    2014-04-01

    Full Text Available Cork, natural and renewable product, has thermal and acoustic properties very interesting because of its microstructure and porosity representing a significant portion of its apparent volume; it’s coming from Moroccan Maamora’s forest. This work is a contribution to understand the thermal behaviour of the composite material based on granular cork embedded in white cement. An experimental investigation of its thermal properties was mainly performed using the asymmetrical device of transient Hot Plate method. The effect of granular cork size on the thermal properties of the mixture was studied. The experimental study of this sustainable material aims to characterize its thermal properties and then compare them with those of white cement without cork for motivate the proposal that this composite material will be used as walls insulator. A comparison of the energy performances of the composite material and white cement was made; it allows deducing a very interesting energy gain. The findings of the experiments indicate that the composite is better than white cement in term of thermal insulation, energy storage capacity and lightness. So, it can be used to realize the internal walls insulation. Its utilization should contribute to the improvement of the energy efficiency in building especially that this is a mixture based on a sustainable and renewable material.

  4. Composite Materials Based on Hemp and Flax for Low-Energy Buildings.

    Science.gov (United States)

    Brzyski, Przemysław; Barnat-Hunek, Danuta; Suchorab, Zbigniew; Łagód, Grzegorz

    2017-05-07

    The article presents the results obtained in the course of a study on prospective application of flax/hemp wastes as a filling material of lime-based composites in the construction of low-energy buildings. The utilized filler comprised the hydrated lime with clay and Portland cement used as additives. The analysis involved evaluation of such properties as porosity, density, thermal conductivity, absorptivity, permeability, as well as compressive and flexural strength. Depending on the quantity of the filler, the properties of the composite changed. This, in turn, enabled to evaluate whether the utilized composite met the thermal requirements established for low-energy buildings. Afterwards, the obtained data were cross-referenced with the results gathered in the case of a room built of autoclaved aerated concrete. In order to prevent reaching the critical surface humidity, the internal surface temperature had to be calculated. Moreover, the chances of interstitial condensation occurring in the wall made of the analyzed lime-flax-hemp composite were determined as well. The study showed that the composite exhibits low strength, low density, low thermal conductivity, and high absorptivity. The external walls made of the lime-flax-hemp composite receive a limited exposure to condensation, but not significant enough to constitute any threat. The requirements established for low-energy buildings can be met by using the analyzed composite.

  5. Material and Social Construction: A Framework for the Adaptation of Buildings

    Directory of Open Access Journals (Sweden)

    Jesse M. Keenan

    2014-12-01

    Full Text Available This article is a formulation of a framework for understanding the nature of change, particularly climate change, as it applies to the scale of a building. Through an exploration of various scientific and social scientific literutre, the article positions the concept of adaptation as the appropriate mode for understanding and managing change. Through the classification of a duality of material and social construction in the ontological composition of a building, various lines of thought relating to adaptive capacity and adaptive cycling within systems theory are appropriated within an integrated framework for adaptation. Specifically, it is theorized that as buildings as objects are developing greater capacities for intergrated operations and management through artificial intelligence, they will possess an ex ante capacity to autonomously adapt in dynamic relation to and with the ex post adaptation of owners and operators. It is argued that this top-down and bottom-up confluence of multi-scalar dynamic change is consistent with the prevailing theory of Panarchy applied in social-ecological systems theory. The article concludes with normative perspectives on the limitations of systems theory in architecture, future directions for research and an alternative positioning of professional practices.

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

    Science.gov (United States)

    Ravisankar, R; Vanasundari, K; Chandrasekaran, A; Rajalakshmi, A; Suganya, M; Vijayagopal, P; Meenakshisundaram, V

    2012-04-01

    The natural level of radioactivity in building materials is one of the major causes of external exposure to γ-rays. The primordial radionuclides in building materials are one of the sources of radiation hazard in dwellings made of these materials. By the determination of the radioactivity level in building materials, the indoor radiological hazard to human health can be assessed. This is an important precautionary measure whenever the dose rate is found to be above the recommended limits. The aim of this work was to measure the specific activity concentration of (226)Ra, (232)Th and (40)K in commonly used building materials from Namakkal, Tamil Nadu, India, using gamma-ray spectrometer. The radiation hazard due to the total natural radioactivity in the studied building materials was estimated by different approaches. The concentrations of the natural radionuclides and the radium equivalent activity in studied samples were compared with the corresponding results of different countries. From the analysis, it is found that these materials may be safely used as construction materials and do not pose significant radiation hazards. Copyright © 2011 Elsevier Ltd. All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    Yoo Yong Ho

    2013-11-01

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

  8. New Porous Material Made from Industrial and Municipal Waste for Building Application

    Directory of Open Access Journals (Sweden)

    Diana BAJARE

    2014-09-01

    Full Text Available The aim of this study was to find a new method for usage of the hazardous waste coming from recycling industry. Two hazardous wastes – aluminium recycling final dross or non-metallic product (NMP and lead – silica glass (LSG were investigated. It is generally considered that NMP is a process waste and subject to disposal after residual metal has been recovered from primary dross. NMP is impurities which are removed from the molten metal in dross recycling process and it could be defined as a hazardous waste product in aluminium recycling industry. LSG comes from fluorescence lamp recycling plant and could be classified as hazardous waste due to high amount of lead in the composition and re-melting problems. The new alkali activated material, which can be defined as porous building material, was created. Composition of this material consisted of aluminium recycling waste, recycled fluorescent lamp LSG, sintered kaolin clay as well as commercially available alkali flakes (NaOH and liquid glass (Na2SiO3 + nH2O. Physical and mechanical properties of the obtained material were tested. Density of the obtained material was from (460 – 550 kg/m3 and the total porosity was from 82 % – 83 %. The compressive strength of the material was in range from 1.1 MPa to 2.3 MPa. The thermal conductivity was determined. The pore microstructure was investigated and the mineralogical composition of porous material was determined. DOI: http://dx.doi.org/10.5755/j01.ms.20.3.4330

  9. The Effect of Cyclic Loading on the Compressive Strength of Core Build-Up Materials.

    Science.gov (United States)

    Zankuli, Muayed A; Silikas, Nick; Devlin, Hugh

    2015-01-15

    To evaluate the effect of cyclic loading on compressive strength of core build-up materials. Four dual-cured composites (Core.X Flow, Grandio Core, Bright Flow Core, Spee-Dee) and one light-cured reinforced resin-modified glass ionomer (Fuji II LC) were tested. One hundred cylindrical specimens (4 mm × 6 mm) were prepared. Each material had two groups (ten specimens to be tested under static loading and ten specimens to be tested after cyclic loading). The specimens were stored wet, and after 30 days, one group of each material was cyclically loaded (for 250,000 cycles with a frequency of 1.6 Hz under stress load of 68.6 N) in a chewing simulator CS-4.2. Then specimens were subjected to static compressive loading until failure in a universal testing machine. Mean compressive strength values before cycling ranged from 144 MPa (15.8) for Fuji II LC to 277 MPa (23.2) for Grandio Core. Independent t-test showed no statistically significant difference (p > 0.05) in the compressive strength of each material before and after cycling (p = 0.7 Grandio Core, p = 0.3 Core.X Flow, p = 0.6 Bright Flow Core, p = 0.2 Spee-Dee, p = 0.6 Fuji II LC); however, there was a statistically significant difference between the materials when comparing before and after cycling. All tested materials showed no reduction in the compressive strength after cycling. Therefore, the tested materials can survive 1 year in service without a reduction in compressive strength. © 2015 by the American College of Prosthodontists.

  10. Materials used to build the wooden vault over the Plenary Hall in the Spanish Senate Buiding

    Directory of Open Access Journals (Sweden)

    Bustamante, R.

    2012-06-01

    Full Text Available The constituent materials used to build the wooden vault over the Plenary Hall in the Spain’s Senate Building (ca 1814-1820 are analyzed in this paper. Characteristics of gypsum mortar applied on pine beams, boards and blockboard, have been determined. The esparto (=needlegrass fibre provides a framework for the gypsum mortar to ensure adhesion and forming the surface of the dome. Physical-mechanical properties of the burnt clay-lightened gypsum mortars were determined with laboratory tests, while the composition of these materials was found with XRD,SEM and IR.

    En este artículo se analizan los materiales de la bóveda encamonada que cubre el Salón de Plenos del Senado de España (hacia 1814-1820. Se han determinado en particular las características físico-mecánicas del mortero de yeso aplicado sobre vigas, tablas y enlistonados de madera de pino, entomizados con fibra de esparto para asegurar la adherencia y conformar la superficie de la bóveda. Con los análisis de DRX, SEM e IR, se ha completado la caracterización del mortero que presenta adiciones de cerámica cocida.

  11. Impact of Water Chemistry, Pipe Material and Stagnation on the Building Plumbing Microbiome.

    Science.gov (United States)

    Ji, Pan; Parks, Jeffrey; Edwards, Marc A; Pruden, Amy

    2015-01-01

    A unique microbiome establishes in the portion of the potable water distribution system within homes and other buildings (i.e., building plumbing). To examine its composition and the factors that shape it, standardized cold water plumbing rigs were deployed at the treatment plant and in the distribution system of five water utilities across the U.S. Three pipe materials (copper with lead solder, CPVC with brass fittings or copper/lead combined pipe) were compared, with 8 hour flush cycles of 10 minutes to simulate typical daily use patterns. High throughput Illumina sequencing of 16S rRNA gene amplicons was employed to profile and compare the resident bulk water bacteria and archaea. The utility, location of the pipe rig, pipe material and stagnation all had a significant influence on the plumbing microbiome composition, but the utility source water and treatment practices were dominant factors. Examination of 21 water chemistry parameters suggested that the total chlorine concentration, pH, P, SO42- and Mg were associated with the most of the variation in bulk water microbiome composition. Disinfectant type exerted a notably low-magnitude impact on microbiome composition. At two utilities using the same source water, slight differences in treatment approaches were associated with differences in rare taxa in samples. For genera containing opportunistic pathogens, Utility C samples (highest pH of 9-10) had the highest frequency of detection for Legionella spp. and lowest relative abundance of Mycobacterium spp. Data were examined across utilities to identify a true universal core, special core, and peripheral organisms to deepen insight into the physical and chemical factors that shape the building plumbing microbiome.

  12. Impact of Water Chemistry, Pipe Material and Stagnation on the Building Plumbing Microbiome.

    Directory of Open Access Journals (Sweden)

    Pan Ji

    Full Text Available A unique microbiome establishes in the portion of the potable water distribution system within homes and other buildings (i.e., building plumbing. To examine its composition and the factors that shape it, standardized cold water plumbing rigs were deployed at the treatment plant and in the distribution system of five water utilities across the U.S. Three pipe materials (copper with lead solder, CPVC with brass fittings or copper/lead combined pipe were compared, with 8 hour flush cycles of 10 minutes to simulate typical daily use patterns. High throughput Illumina sequencing of 16S rRNA gene amplicons was employed to profile and compare the resident bulk water bacteria and archaea. The utility, location of the pipe rig, pipe material and stagnation all had a significant influence on the plumbing microbiome composition, but the utility source water and treatment practices were dominant factors. Examination of 21 water chemistry parameters suggested that the total chlorine concentration, pH, P, SO42- and Mg were associated with the most of the variation in bulk water microbiome composition. Disinfectant type exerted a notably low-magnitude impact on microbiome composition. At two utilities using the same source water, slight differences in treatment approaches were associated with differences in rare taxa in samples. For genera containing opportunistic pathogens, Utility C samples (highest pH of 9-10 had the highest frequency of detection for Legionella spp. and lowest relative abundance of Mycobacterium spp. Data were examined across utilities to identify a true universal core, special core, and peripheral organisms to deepen insight into the physical and chemical factors that shape the building plumbing microbiome.

  13. Inoculation of Pichia kudriavzevii RB1 degrades the organic acids present in raw compost material and accelerates composting.

    Science.gov (United States)

    Nakasaki, Kiyohiko; Araya, Shogo; Mimoto, Hiroshi

    2013-09-01

    In this study, the yeast strain Pichia kudriavzevii RB1 was used as an inoculum to accelerate organic matter degradation of rabbit food with added organic acids, which was used as a model food waste for composting. The RB1 strain rapidly degraded the organic acids present in the raw compost material, leading to an increase in pH beyond the neutral level, within 2 days. Both mesophilic and thermophilic bacteria proliferated faster in the compost with RB1 inoculation than in that without inoculation. Although the yeast died with the increase in compost temperature, it affected the early stages of composting prior to the thermophilic stage and accelerated the composting process by 2 days by eliminating the initial lag phase seen in the growth of other microorganisms. Moreover, populations of Bacillus thermoamylovorans, Bacillus foraminis, and Bacillus coagulans became dominant during the thermophilic stages of both composting with and without RB1 inoculation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Photocurrent Spectroscopy of Perovskite Layers and Solar Cells: A Sensitive Probe of Material Degradation

    KAUST Repository

    Holovský, Jakub

    2017-01-25

    Optical absorptance spectroscopy of polycrystalline CHNHPbI films usually indicates the presence of a PbI phase, either as a preparation residue or due to film degradation, but gives no insight on how this may affect electrical properties. Here, we apply photocurrent spectroscopy to both perovskite solar cells and coplanar-contacted layers at various stages of degradation. In both cases, we find that the presence of a PbI phase restricts charge-carrier transport, suggesting that PbI encapsulates CHNHPbI grains. We also find that PbI injects holes into the CHNHPbI grains, increasing the apparent photosensitivity of PbI. This phenomenon, known as modulation doping, is absent in the photocurrent spectra of solar cells, where holes and electrons have to be collected in pairs. This interpretation provides insights into the photogeneration and carrier transport in dual-phase perovskites.

  15. Degradation of proton depth dose distributions attributable to microstructures in lung-equivalent material.

    Science.gov (United States)

    Titt, Uwe; Sell, Martin; Unkelbach, Jan; Bangert, Mark; Mirkovic, Dragan; Oelfke, Uwe; Mohan, Radhe

    2015-11-01

    The purpose of the work reported here was to investigate the influence of sub-millimeter size heterogeneities on the degradation of the distal edges of proton beams and to validate Monte Carlo (MC) methods' ability to correctly predict such degradation. A custom-designed high-resolution plastic phantom approximating highly heterogeneous, lung-like structures was employed in measurements and in Monte Carlo simulations to evaluate the degradation of proton Bragg curves penetrating heterogeneous media. Significant differences in distal falloff widths and in peak dose values were observed in the measured and the Monte Carlo simulated curves compared to pristine proton Bragg curves. Furthermore, differences between simulations of beams penetrating CT images of the phantom did not agree well with the corresponding experimental differences. The distal falloff widths in CT image-based geometries were underestimated by up to 0.2 cm in water (corresponding to 0.8-1.4 cm in lung tissue), and the peak dose values of pristine proton beams were overestimated by as much as ˜35% compared to measured curves or depth-dose curves simulated on the basis of true geometry. The authors demonstrate that these discrepancies were caused by the limited spatial resolution of CT images that served as a basis for dose calculations and lead to underestimation of the impact of the fine structure of tissue heterogeneities. A convolution model was successfully applied to mitigate the underestimation. The results of this study justify further development of models to better represent heterogeneity effects in soft-tissue geometries, such as lung, and to correct systematic underestimation of the degradation of the distal edge of proton doses.

  16. Efficiency of application of complex nanomodifying additives based on zeolites in building materials

    Directory of Open Access Journals (Sweden)

    PАNINА Tatyana Ivanovna

    2016-10-01

    Full Text Available The paper considers the possibility of using integrated multifunctional additives based on carbon nanotubes and zeolites (natural and synthetic in construction materials. The nanotubes were produced by catalytic chemical vapor deposition. The streamlined modification of the zeolite structure was performed by impregnating initial materials with a nanotubes-supported catalyst. The present experimental research focused on studying the effect of the synthesized nanomodifying additive on the physicomechanical properties of a composite construction material. Based on the obtained data, it was assumed that when entering the concrete structure, zeolite acts not only as mineral additive but also as nanotubes carrier under the chosen nanomodification conditions for the construction material, thereby allowing for uniform distribution of carbon nanoparticles in the composite matrix; on the other hand, the adsorption properties of zeolite can be reinforced by the presence of carbon in the structure. Structures of nanomodifying zeolites and obtained building composite were evaluated by scanning electron microscopy (SEM. Electron micrographs of the objects makes it possible to explain the processes of formation of the concrete structure, nanomodified complex multifunctional additive based on synthetic and natural zeolites and carbon nanomaterial.

  17. PRESENT-DAY AND FUTURE APPLICATIONS OF NANOTECHNOLOGIES IN THE PRODUCTION OF BUILDING MATERIALS

    Directory of Open Access Journals (Sweden)

    Shuyskiy Anatoliy Ivanovich

    2012-12-01

    Full Text Available The authors have made an overview of the status of production of cement concrete using nanotechnologies. The authors also provide their analysis of domestic and foreign researches into the application of nanotechnologies in the field of building materials. The authors have picked out positive examples of introduction of nano-scale particles into the concrete mix. The process needs continuous monitoring for the composition and the mixing time to be adjustable. The findings have been solely made by local developers of nano-materials and technologies. The authors propose their method of cement consumption reduction through the introduction of nanoparticles and simultaneous grinding of cement. The authors provide a new procedure of treatment of materials that contemplates enhanced mixing processes accompanied by simultaneous grinding of materials and their exposure to the electromagnetic treatment. The experiments completed by the team of authors have proven the efficiency of a combination of two nanotechnologies within one process, including the treatment of wet cement at the final grinding stage of processing to ensure specific cement properties for a specific surface area of 8,000 cm2/g, and the introduction of nano-scale particles into the process of manufacturing of cement compositions. The use of carbon nanotubes in the process of manufacturing of cement concrete can improve its physical and mechanical properties and reduce the cement consumption rate while maintaining the design strength of concrete.

  18. The Monastery of Uclés (Cuenca, Spain: characterization and deterioration of building materials

    Directory of Open Access Journals (Sweden)

    Álvarez De Buergo, M.

    2004-09-01

    Full Text Available Building materials from the Monastery of Uclés façades, in Cuenca (16th-18 th centuries, have been characterised, as well as identified their deterioration forms. Characterization consisted of the determination o mineralogical and petrographical properties of building materials; petrophysical and petrochemical characterization of building stones were also carried out. Stony materials are basically of two types, dolostones and limestones. Ashlars joint mortars are of three classes, chronologically from the oldest to the newest: lime mortars with siliceous and dolomitic aggregates, gypsum/lime mortars with dolomitic aggregates, and gypsum/lime mortars with siliceous aggregates. The façades have been protected with artificial patinas of three kinds: lime, lime/gypsum and gypsum patinas, chronologically from the oldest to the newest, with a variable thickness from 500 µm. The dolomitic fades are better conserved than the calcareous ones, and the covering artificial patinas presence have preserved the materials on which they were applied.

    Se han caracterizado ¡os materiales de construcción de las fachadas del Monasterio de Uclés en Cuenca (s. XVI-XVIII así como sus formas de deterioro. La caracterización consistió en la determinación de sus características mineralógicas, petrográficas y petroquímicas, asi como la caracterización petrofisica de los materiales pétreos. Las piedras de construcción son, fundamentalmente, de dos tipos, dolomías y calizas. Los morteros de rejuntado de los sillares son de tres tipos, en orden cronológico, de más antiguos a más modernos: morteros de cal con áridos silíceos y dolomíticos, morteros de cal/yeso con áridos dolomílicos, y morteros de yeso/cal con áridos silíceos. Las fachadas han estado protegidas por pátinas artificiales de tres tipos: de cal, de cal/yeso y de yeso; en orden cronológico, de más antiguas a más modernas, con espesores variables desde < 100µm

  19. Integrating Concepts of Material Mechanics, Ligand Chemistry, Dimensionality and Degradation to Control Differentiation of Mesenchymal Stem Cells.

    Science.gov (United States)

    Haugh, Matthew G; Heilshorn, Sarah C

    2016-08-01

    The role of substrate mechanics in guiding mesenchymal stem cell (MSC) fate has been the focus of much research over the last decade. More recently, the complex interplay between substrate mechanics and other material properties such as ligand chemistry and substrate degradability to regulate MSC differentiation has begun to be elucidated. Additionally, there are several changes in the presentation of these material properties as the dimensionality is altered from two- to three-dimensional substrates, which may fundamentally alter our understanding of substrate-induced mechanotransduction processes. In this review, an overview of recent findings that highlight the material properties that are important in guiding MSC fate decisions is presented, with a focus on underlining gaps in our existing knowledge and proposing potential directions for future research.

  20. E-Area Vault Concrete Material Property And Vault Durability/Degradation Projection Recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Phifer, M. A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2014-03-11

    Subsequent to the 2008 E-Area Low-Level Waste Facility (ELLWF) Performance Assessment (PA) (WSRC 2008), two additional E-Area vault concrete property testing programs have been conducted (Dixon and Phifer 2010 and SIMCO 2011a) and two additional E-Area vault concrete durability modeling projections have been made (Langton 2009 and SIMCO 2012). All the information/data from these reports has been evaluated and consolidated herein by the Savannah River National Laboratory (SRNL) at the request of Solid Waste Management (SWM) to produce E-Area vault concrete hydraulic and physical property data and vault durability/degradation projection recommendations that are adequately justified for use within associated Special Analyses (SAs) and future PA updates. The Low Activity Waste (LAW) and Intermediate Level (IL) Vaults structural degradation predictions produced by Carey 2006 and Peregoy 2006, respectively, which were used as the basis for the 2008 ELLWF PA, remain valid based upon the results of the E-Area vault concrete durability simulations reported by Langton 2009 and those reported by SIMCO 2012. Therefore revised structural degradation predictions are not required so long as the mean thickness of the closure cap overlying the vaults is no greater than that assumed within Carey 2006 and Peregoy 2006. For the LAW Vault structural degradation prediction (Carey 2006), the mean thickness of the overlying closure cap was taken as nine feet. For the IL Vault structural degradation prediction (Peregoy 2006), the mean thickness of the overlying closure cap was taken as eight feet. The mean closure cap thicknesses as described here for both E-Area Vaults will be included as a key input and assumption (I&A) in the next revision to the closure plan for the ELLWF (Phifer et al. 2009). In addition, it has been identified as new input to the PA model to be assessed in the ongoing update to the new PA Information UDQE (Flach 2013). Once the UDQE is approved, the SWM Key I

  1. Stability of CIGS Solar Cells and Component Materials Evaluated by a Step-Stress Accelerated Degradation Test Method: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Pern, F. J.; Noufi, R.

    2012-10-01

    A step-stress accelerated degradation testing (SSADT) method was employed for the first time to evaluate the stability of CuInGaSe2 (CIGS) solar cells and device component materials in four Al-framed test structures encapsulated with an edge sealant and three kinds of backsheet or moisture barrier film for moisture ingress control. The SSADT exposure used a 15oC and then a 15% relative humidity (RH) increment step, beginning from 40oC/40%RH (T/RH = 40/40) to 85oC/70%RH (85/70) as of the moment. The voluminous data acquired and processed as of total DH = 3956 h with 85/70 = 704 h produced the following results. The best CIGS solar cells in sample Set-1 with a moisture-permeable TPT backsheet showed essentially identical I-V degradation trend regardless of the Al-doped ZnO (AZO) layer thickness ranging from standard 0.12 μm to 0.50 μm on the cells. No clear 'stepwise' feature in the I-V parameter degradation curves corresponding to the SSADT T/RH/time profile was observed. Irregularity in I-V performance degradation pattern was observed with some cells showing early degradation at low T/RH < 55/55 and some showing large Voc, FF, and efficiency degradation due to increased series Rs (ohm-cm2) at T/RH ≥ 70/70. Results of (electrochemical) impedance spectroscopy (ECIS) analysis indicate degradation of the CIGS solar cells corresponded to increased series resistance Rs (ohm) and degraded parallel (minority carrier diffusion/recombination) resistance Rp, capacitance C, overall time constant Rp*C, and 'capacitor quality' factor (CPE-P), which were related to the cells? p-n junction properties. Heating at 85/70 appeared to benefit the CIGS solar cells as indicated by the largely recovered CPE-P factor. Device component materials, Mo on soda lime glass (Mo/SLG), bilayer ZnO (BZO), AlNi grid contact, and CdS/CIGS/Mo/SLG in test structures with TPT showed notable to significant degradation at T/RH ≥ 70/70. At T/RH = 85/70, substantial blistering of

  2. Natural radionuclide content in building materials and gamma dose rate in dwellings in Cuba

    Energy Technology Data Exchange (ETDEWEB)

    Brigido Flores, O. [Department of Applied Nuclear Techniques and Environmental Monitoring, Environmental Engineering Centre of Camagoeey, Ave. Finlay km 2.5, Esquina Circunvalacion, Rpto. Puerto Principe, Camagueey 8, CP 70800, Camagueey (Cuba)], E-mail: o.brigido@ciac.cmw.inf.cu; Montalvan Estrada, A.; Rosa Suarez, R. [Department of Applied Nuclear Techniques and Environmental Monitoring, Environmental Engineering Centre of Camagoeey, Ave. Finlay km 2.5, Esquina Circunvalacion, Rpto. Puerto Principe, Camagueey 8, CP 70800, Camagueey (Cuba); Tomas Zerquera, J. [Centre for Radiation Protection and Hygiene, 20 St. No. 4109, Miramar, PO Box 6195, Havana 6, Havana City (Cuba); Hernandez Perez, A. [Environmental Radiological Monitoring Laboratory, Centre for Environmental Studies of Holguin, Pachuco Feria No. 46, Rpto. Peralta, Holguin (Cuba)

    2008-12-15

    An extensive research project to investigate the radioactive properties of Cuban building materials was carried out because there is a lack of information on the radioactivity of such materials in Cuba. In the framework of this project 44 samples of commonly used raw materials and building products were collected in five Cuban provinces. The activity concentrations of natural radionuclides were determined by gamma ray spectrometry using a p-type coaxial high purity germanium detector and their mean values were in the ranges: 9-857 Bq kg{sup -1} for {sup 40}K; 6-57 Bq kg{sup -1} for {sup 226}Ra; and 1.2-22 Bq kg{sup -1} for {sup 232}Th. The radium equivalent activity in the 44 samples varied from 4 Bq kg{sup -1} (wood) to 272 Bq kg{sup -1} (brick). A high pressure ionisation chamber was used to measure the indoor absorbed dose rate in 543 dwellings and workplaces in five Cuban provinces. The average absorbed dose rates in air ranged from 43 nGy h{sup -1} (Holguin) to 73 nGy h{sup -1} (Camagueey) and the corresponding population-weighted annual effective dose due to external gamma radiation was estimated to be 145 {+-} 40 {mu}Sv. This value is 51% lower than the effective dose due to internal exposure from inhalation of decay products of {sup 222}Rn and {sup 220}Rn and it is 16% higher than the calculated value for the typical room geometry of a Cuban house.

  3. Assessing degradation rates of chlorinated ethylenes in column experiments with commercial iron materials used in permeable reactive barriers.

    Science.gov (United States)

    Ebert, Markus; Köber, Ralf; Parbs, Anika; Plagentz, Volkmar; Schäfer, Dirk; Dahmke, Andreas

    2006-03-15

    Multiple column experiments were performed using two commercial iron materials to evaluate the necessity and usefulness of preliminary investigations in permeable reactive barrier (PRB) design for chlorinated organics. Experiments were performed with contaminated groundwater and involved fresh iron granules or altered iron material excavated from PRBs. The determination of first-order rate coefficients by global nonlinear least-squares fittings indicated a variability in rate coefficients on 1 or 2 orders of magnitude. Geometric mean values of surface area normalized rate coefficients (in 10(-5) L m(-2) h(-1)) for fresh gray cast iron and iron sponge, respectively, are: tetrachloroethene (4.5, 2.6), trichloroethene (8.1, 3.3), cis-1,2-dichloroethene (3.1, 2.9), trans-1,2-dichloroethene (9.5, 5.3), 1,1-dichloroethene (4.0, 4.4), and vinyl chloride (1.6, 6.1). The increasing rate coefficients with decreasing grade of chlorination, which characterize degradation at iron sponge are linearly related to diffusion coefficients in water, suggesting diffusion limitation in the degradation process for this particular material, possibly due to a high inner surface. The variability in rate coefficients seems to be too high to use mean rate coefficients from published studies in the design procedure of PRBs, and variabilities cannot be related to groundwater characteristics, waterflow through the reactive cells, or secondary corrosion reactions.

  4. A study on material degradation in SB 410 carbon steel plates for boilers and other pressure vessels

    Energy Technology Data Exchange (ETDEWEB)

    Baek, U. B.; Park, J. S. [Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of); Nam, K. W.; Kim, H. Y. [Korea Energy Management Corp., Yongin (Korea, Republic of)

    2005-07-01

    In spite of frequent defect in industrial boilers, life assessment or diagnostic method for them has not been studied. In this research, SB410 carbon steel used in industrial boilers is simulated with artificial aging heat treatment. To do qualitative life assessment, differences in micro-structures and hardness of SB410 by the degradation time are studied. In addition, variation in material properties by aging was observed with the tensile test at room temperature and 179 .deg. C and changes in ductile to brittle transition temperature was observed with the charpy impact test performed at several test temperature.

  5. Modeling of thermal mass energy storage in buildings with phase change materials

    Science.gov (United States)

    Delcroix, Benoit

    Building thermal mass is a key parameter defining the ability of a building to mitigate inside temperature variations and to maintain a better thermal comfort. Increasing the thermal mass of a lightweight building can be achieved by using Phase Change Materials (PCMs). These materials offer a high energy storage capacity (using latent energy) and a nearly constant temperature phase change. They can be integrated conveniently in net-zero energy buildings. The current interest for these buildings and for better power demand management strategies requires accurate transient simulation of heavy and highly insulated slabs or walls with short time-steps (lower than or equal to 5 minutes). This represents a challenge for codes that were mainly developed for yearly energy load calculations with a time-step of 1 hour. It is the case of the TRNSYS building model (called Type 56) which presents limitations when modeling heavy and highly insulated slabs with short time-steps. These limitations come from the method used by TRNSYS for modeling conduction heat transfer through walls which is known as the Conduction Transfer Function (CTF) method. In particular, problems have been identified in the generation of CTF coefficients used to model the walls thermal response. This method is also unable to define layers with variable thermophysical properties, as displayed by PCMs. PCM modeling is further hindered by the limited information provided by manufacturers: physical properties are often incomplete or incorrect. Finally, current models are unable to represent the whole complexity of PCM thermal behavior: they rarely include different properties for melting and solidification (hysteresis); they sometimes take into account variable thermal conductivity; but they never model subcooling effects. All these challenges are tackled in this thesis and solutions are proposed. The first part (chapter 4) focuses on improving the CTF method in TRNSYS through state-space modeling

  6. Measurement of color in different construction materials. The restoration in sandstone buildings

    Directory of Open Access Journals (Sweden)

    García Pascua, N.

    1999-03-01

    Full Text Available The use of construction materials and their subsequent repair purposes include a search of knowledge and preservation of their original appearance. For this reason, the main aim of this study is to determine a color range which does not change with the possible actions on a building, both when restoration works which imply the use and repair of "ancient" materials are carried out, and when construction is carried out with new materials. It is necessary to obtain the quantification of this property in order to check its variation over the passage of time. Each construction material must be taken into account as an isolated problem, since the color is different in each case.

    El empleo de materiales de construcción y la aplicación sobre ellos de productos de reparación requiere un detallado estudio sobre su forma de actuación y la importancia de la conservación del aspecto original de los mismos. Por este motivo, el objetivo principal de este estudio es el determinar un intervalo de color que se conserve a pesar de todas las posibles intervenciones que se acometan en el edificio, tanto cuando se realizan trabajos de restauración, que implican el uso y reparación de materiales "viejos", o bien cuando se llevan a cabo trabajos de construcción con materiales nuevos. Es necesario cuantificar dicha propiedad para poder controlar el paso del tiempo. Cada material de construcción debe ser considerado como un problema aislado, ya que el color es distinto en cada caso.

  7. First characterisation of natural radioactivity in building materials manufactured in Albania.

    Science.gov (United States)

    Xhixha, G; Ahmeti, A; Bezzon, G P; Bitri, M; Broggini, C; Buso, G P; Caciolli, A; Callegari, I; Cfarku, F; Colonna, T; Fiorentini, G; Guastaldi, E; Mantovani, F; Massa, G; Menegazzo, R; Mou, L; Prifti, D; Rossi Alvarez, C; Sadiraj Kuqi, Dh; Shyti, M; Tushe, L; Xhixha Kaçeli, M; Zyfi, A

    2013-07-01

    This study focuses on the radiological characterisation of building materials manufactured in Albania by using a high-resolution gamma-ray spectrometer. The average activity concentrations of (40)K, (226)Ra and (232)Th were, respectively, 644.1±64.2, 33.4 ± 6.4 and 42.2 ± 7.6 Bq kg(-1) in the clay brick samples and 179.7 ± 48.9, 55.0 ± 5.8 and 17.0 ± 3.3 Bq kg(-1) in the cement samples. The calculated activity concentration index (ACI), varied from 0.48±0.02 to 0.63±0.04 in the clay brick samples and from 0.29±0.03 to 0.37±0.02 in the cement samples. Based on the ACI, all of the clay brick and cement samples were categorised as A1 materials. The authors can exclude (at 3σ level) any restriction of their use as bulk materials.

  8. Influence of mechanical and chemical degradation on surface gloss of resin composite materials

    NARCIS (Netherlands)

    Ardu, S.; Braut, V.; Uhac, I.; Benbachir, N.; Feilzer, A.J.; Krejci, I.

    2009-01-01

    Purpose: To determine the changes in surface gloss of different composite materials after simulation of mechanical and chemical aging mechanisms. Methods: 36 specimens were fabricated for each material and polished with 120-, 220-, 500-, 1200-, 2400- and 4000- grit SiC abrasive paper, respectively.

  9. Quantification of tactile effect of building materials. Shokkaku ni yoru kenchiku shiage zairyo no kaiter dot fukaikan no teiryoka

    Energy Technology Data Exchange (ETDEWEB)

    Okajima, T.; Wu, J. (Nagoya Institute of Technology, Nagoya (Japan)); Takeda, Y. (Imamiya Technical High School, Osaka (Japan))

    1991-09-15

    The purpose of this paper is to clarify the quantification of the tactile effect of building finishing materials from their physical properties. On the basis of psychology and physiology, sensation and perception were interpreted. Three fundamental physical values, i.e., warmth, hardness, and roughness were taken up as the physical properties of the materials, and the relationship between these physical properties and the pleasant and unpleasant sensation was analyzed. For the measurement of perception of pleasant and unpleasant sensation, the method of sensory inspection or mental measurement was applied. Then, the concept of psychophysio-dynamics was proposed connecting psychophysics with psychodynamics. As a result, it was found out that the tactile effect of building finishing materials can be predicted from the physical values of warmth, hardness, and roughness. Furthermore, a psychological experiment was performed using 66 building finishing materials. As a result, the applicability of the method proposed in this paper was verified. 35 refs., 6 figs.

  10. Energy balance associated with the degradation of lignocellulosic material by white-rot and brown-rot fungi.

    Science.gov (United States)

    Derrien, Delphine; Bédu, Hélène; Buée, Marc; Kohler, Annegret; Goodell, Barry; Gelhaye, Eric

    2017-04-01

    Forest soils cover about 30% of terrestrial area and comprise between 50 and 80% of the global stock of soil organic carbon (SOC). The major precursor for this forest SOC is lignocellulosic material, which is made of polysaccharides and lignin. Lignin has traditionally been considered as a recalcitrant polymer that hinders access to the much more labile structural polysaccharides. This view appears to be partly incorrect from a microbiology perspective yet, as substrate alteration depends on the metabolic potential of decomposers. In forest ecosystems the wood-rotting Basidiomycota fungi have developed two different strategies to attack the structure of lignin and gain access to structural polysaccharides. White-rot fungi degrade all components of plant cell walls, including lignin, using enzymatic systems. Brown-rot fungi do not remove lignin. They generate oxygen-derived free radicals, such as the hydroxyl radical produced by the Fenton reaction, that disrupt the lignin polymer and depolymerize polysaccharides which then diffuse out to where the enzymes are located The objective of this study was to develop a model to investigate whether the lignin relative persistence could be related to the energetic advantage of brown-rot degradative pathway in comparison to white-rot degradative pathway. The model simulates the changes in substrate composition over time, and determines the energy gained from the conversion of the lost substrate into CO2. The energy cost for the production of enzymes involved in substrate alteration is assessed using information derived from genome and secretome analysis. For brown-rot fungus specifically, the energy cost related to the production of OH radicals is also included. The model was run, using data from the literature on populous wood degradation by Trametes versicolor, a white-rot fungus, and Gloeophyllum trabeum, a brown-rot fungus. It demonstrates that the brown-rot fungus (Gloeophyllum trabeum) was more efficient than the white

  11. The anaerobic degradability of thermoplastic starch: polyvinyl alcohol blends: potential biodegradable food packaging materials.

    Science.gov (United States)

    Russo, Melissa A L; O'Sullivan, Cathryn; Rounsefell, Beth; Halley, Peter J; Truss, Rowan; Clarke, William P

    2009-03-01

    A systematic study on the anaerobic degradability of a series of starch:polyvinyl alcohol (TPS:PVOH) blends was performed to determine their fate upon disposal in either anaerobic digesters or bioreactor landfills. The aims of the study were to measure the rate and extent of solubilisation of the plastics. The extent of substrate solubilisation on a COD basis reached 60% for a 90:10 (w/w) blend of TPS:PVOH, 40% for 75:25, 30% for 50:50 and 15% for PVOH only. The rate of substrate solubilisation was most rapid for the 90:10 blend (0.041 h(-1)) and decreased with the amount of starch in the blend in the following order 0.034 h(-1)(75:25); 0.023 h(-1)(50:50). The total solids that remained after 900 h were 10 wt.% (90:10); 23 wt.% (75:25); 55 wt.% (50:50); 90 wt.% (0:100). Starch containing substrates produced a higher concentration of volatile fatty acids (VFAs) and biogas, compared to the 0:100 substrate. The major outcome was that PVOH inhibited the degradation of the starch from the blend.

  12. Degradation of zinc containing phosphate-based glass as a material for orthopedic tissue engineering.

    Science.gov (United States)

    Qaysi, Mustafa Al; Petrie, Aviva; Shah, Rishma; Knowles, Jonathan C

    2016-10-01

    Phosphate-based glasses have been examined in many studies as a potential biomaterial for bone repair because of its degradation properties, which can be controlled and allow the release of various elements to promote osteogenic tissue growth. However most of these experiments studied either tertiary or quaternary glass systems. This study investigated a qinternary system that included titanium dioxide for degradation rate control and zinc that is considered to have a role in bone formation. Zinc and titanium phosphate glass discs of different compositions were melt synthesized and samples of each composition was tested for different physical, chemical and biological characteristics via density measurement, X-ray diffraction, differential thermal analysis, mass loss, ion release, scanning electron microscopy, biocompatibility studies via live/dead assays at three time points (day 1, 4, and 7). The results showed that the glass was amorphous and that the all thermal variables decreased as zinc oxide amount raised, mass loss as well as ion release increased as zinc oxide increased, and the maximum rise was with ZnO15. The cellular studies showed that all the formulation showed similar cytocompatibility properties with MG63 except ZnO15, which displayed cytotoxic properties and this was confirmed also by the scanning electron microscope images. In conclusion, replacing calcium oxide with zinc oxide in proportion less than 10 % can have a positive effect on bone forming cells.

  13. Preparation and Characterization of Microencapsulated Phase Change Materials for Use in Building Applications

    Directory of Open Access Journals (Sweden)

    Jessica Giro-Paloma

    2015-12-01

    Full Text Available A method for preparing and characterizing microencapsulated phase change materials (MPCM was developed. A comparison with a commercial MPCM is also presented. Both MPCM contained paraffin wax as PCM with acrylic shell. The melting temperature of the PCM was around 21 °C, suitable for building applications. The M-2 (our laboratory made sample and Micronal® DS 5008 X (BASF samples were characterized using SEM, DSC, nano-indentation technique, and Gas Chromatography/Mass spectrometry (GC-MS. Both samples presented a 6 μm average size and a spherical shape. Thermal energy storage (TES capacities were 111.73 J·g−1 and 99.3 J·g−1 for M-2 and Micronal® DS 5008 X, respectively. Mechanical characterization of the samples was performed by nano-indentation technique in order to determine the elastic modulus (E, load at maximum displacement (Pm, and displacement at maximum load (hm, concluding that M-2 presented slightly better mechanical properties. Finally, an important parameter for considering use in buildings is the release of volatile organic compounds (VOC’s. This characteristic was studied at 65 °C by CG-MS. Both samples showed VOC’s emission after 10 min of heating, however peaks intensity of VOC’s generated from M-2 microcapsules showed a lower concentration than Micronal® DS 5008 X.

  14. An analysis research of the stiffness characteristics of hospital building materials

    Directory of Open Access Journals (Sweden)

    Chen Yunyu

    2014-10-01

    Full Text Available This paper primarily aims to introduce different stiffness ratio requirements for hospital buildings of various structural styles, to achieve a new standard. The requirements of each stiffness ratio are analyzed, according to the specification formulas and illustrations. And whether the structural deformation situation complies with the code requirement or dissatisfies the specification requests can be intuitively reflected through the application of the chart form, respectively. The corresponding measures complying with the code requirement and the matters needing attention in the schematic design phase are proposed. The comparison analysis for the lateral rigidity and lateral stiffness ratios is performed by applying different methods for the project cases of shear wall, frame tube and partial frame shear wall structures. The proposed computing method may better reflect the stiffness characteristics of the component’s cross-section, with regard to vertical layer, storey height and materials, as well as the actual situation of the turning constraint on both ends. The result thus determined can better reflect the real lateral rigidity of the construction, which is available as a benchmark for engineers designing hospital building structures.

  15. Dynamic thermal behavior of building using phase change materials for latent heat storage

    Directory of Open Access Journals (Sweden)

    Selka Ghouti

    2015-01-01

    Full Text Available This study presents a two-dimensional model with a real size home composed of two-storey (ground and first floor spaces separated by a slab, enveloped by a wall with rectangular section containing phase change material (PCM in order to minimize energy consumption in the buildings. The main objective of the PCM-wall system is to decrease the temperature change from outdoor space before it reaches the indoor space during the daytime. The numerical approach uses effective heat capacity Ceff model with realistic outdoor climatic conditions of Tlemcen city, Algeria. The numerical results showed that by using PCM in wall as energy storage components may reduce the room temperature by about 6 to 7°C of temperature depending on the floor level (first floor spaces or ground floor spaces.

  16. 226Ra, 232Th and 40K ACTIVITY CONCENTRATIONS AND RADIOLOGICAL HAZARDS OF BUILDING MATERIALS IN MUGLA, TURKEY

    Directory of Open Access Journals (Sweden)

    Ezgi Eren Belgin

    2015-11-01

    Full Text Available The activity concentrations of natural gamma-emitting radionuclides in commonly used building materials were measured by using high purity germanium (HPGe detector coupled with a high resolution multichannel analyser. The results associated radiation hazards due to  40K, 226Ra and 232Th have been determined in samples collected randomly from southwest part of Turkey. When the building materials such as clay brick, marble, cement etc. originating from soil and rocks are used in constructions they cause direct ionizing radiation exposure at varying intensities. Different criterion formulas as radium equivalent activity, the external/internal hazard indices, the alpha/gamma indexes and the absorbed dose rate in indoor air were determined to assess the radiation hazards arising due to the use of materials studied for people living in the construction of dwellings made of the these materials. Although indoor absorbed dose rate is relatively higher than the world population-weighted average value and international limit for studied brick and cement samples they could be used safely as building materials because radium equivalent activity, alpha/gamma indices and hazard indices of those materials have been found to be within the recommended limits. All the values for all criterion formulas for marble samples are found to be well below the safety limits recommended by UNSCEAR. It can be concluded that examined materials can be used for construction of buildings for interior and external works.

  17. Comparison of degradation effects induced by gamma radiation and electron beam radiation in two cable jacketing materials

    Energy Technology Data Exchange (ETDEWEB)

    Bartonicek, B. [Nuclear Research Institute Rez plc, Husinec-Rez, cp. 130, 25068 Rez (Czech Republic); Placek, V. [Nuclear Research Institute Rez plc, Husinec-Rez, cp. 130, 25068 Rez (Czech Republic)]. E-mail: pla@ujv.cz; Hnat, V. [Nuclear Research Institute Rez plc, Husinec-Rez, cp. 130, 25068 Rez (Czech Republic)

    2007-05-15

    The radiation degradation behavior of commercial low density polyethylene (LDPE) and ethylene-vinylacetate (EVA) cable materials has been investigated. The changes of mechanical properties, thermooxidative stability and density exhibit different radiation stability towards {sup 60}Co-gamma radiation and 160 keV electron beam radiation. This difference reflects much higher penetration of the gamma radiation through the polymeric material as a function of sample thickness. These results are discussed with respect to the role of beta radiation during design basis events in a nuclear power plants. In case when total accidental design basis event (DBE) dose (involving about 80% soft beta radiation) is simulated by {sup 60}Co-gamma radiation the conservatism is reached.

  18. Influence of mechanical and chemical degradation on surface gloss of resin composite materials.

    Science.gov (United States)

    Ardu, Stefano; Braut, Vedrana; Uhac, Ivone; Benbachir, Nacer; Feilzer, Albert J; Krejci, Ivo

    2009-10-01

    To determine the changes in surface gloss of different composite materials after simulation of mechanical and chemical aging mechanisms. 36 specimens were fabricated for each material and polished with 120-, 220-, 500-, 1200-, 2400- and 4000- grit SiC abrasive paper, respectively. Gloss measurements were made with a glossmeter (Novo-Curve) prior to testing procedures. Specimens of each material were randomly divided into three groups. Group 1 was conditioned for 7 days at 37 degrees C in 75% ethanol aqueous solution. Group 2 was immersed in fluoride gel (Elmex Gelée) at 37 degrees C for 1 hour. Group 3 was subjected to simulated toothbrushing with an electric toothbrush while being immersed in toothpaste. Surface gloss measurements were made subsequently. Significant difference between surface gloss of the composite materials tested were detected after simulated brushing (Kruskal Wallis, P natural enamel and Durafill (Wilcoxon signed-rank test, P< 0.05).

  19. Time-Variant Reliability Analysis for Rubber O-Ring Seal Considering Both Material Degradation and Random Load

    Science.gov (United States)

    Liao, Baopeng; Yan, Meichen; Zhang, Weifang; Zhou, Kun

    2017-01-01

    Due to the increase in working hours, the reliability of rubber O-ring seals used in hydraulic systems of transfer machines will change. While traditional methods can only analyze one of the material properties or seal properties, the failure of the O-ring is caused by these two factors together. In this paper, two factors are mainly analyzed: the degradation of material properties and load randomization by processing technology. Firstly, the two factors are defined in terms of material failure and seal failure, before the experimental methods of rubber materials are studied. Following this, the time-variant material properties through experiments and load distribution by monitoring the processing can be obtained. Thirdly, compressive stress and contact stress have been calculated, which was combined with the reliability model to acquire the time-variant reliability for the O-ring. Finally, the life prediction and effect of oil pressure were discussed, then compared with the actual situation. The results show a lifetime of 12 months for the O-ring calculated in this paper, and compared with the replacement records from the maintenance workshop, the result is credible. PMID:29053597

  20. Time-Variant Reliability Analysis for Rubber O-Ring Seal Considering Both Material Degradation and Random Load.

    Science.gov (United States)

    Liao, Baopeng; Sun, Bo; Yan, Meichen; Ren, Yi; Zhang, Weifang; Zhou, Kun

    2017-10-20

    Due to the increase in working hours, the reliability of rubber O-ring seals used in hydraulic systems of transfer machines will change. While traditional methods can only analyze one of the material properties or seal properties, the failure of the O-ring is caused by these two factors together. In this paper, two factors are mainly analyzed: the degradation of material properties and load randomization by processing technology. Firstly, the two factors are defined in terms of material failure and seal failure, before the experimental methods of rubber materials are studied. Following this, the time-variant material properties through experiments and load distribution by monitoring the processing can be obtained. Thirdly, compressive stress and contact stress have been calculated, which was combined with the reliability model to acquire the time-variant reliability for the O-ring. Finally, the life prediction and effect of oil pressure were discussed, then compared with the actual situation. The results show a lifetime of 12 months for the O-ring calculated in this paper, and compared with the replacement records from the maintenance workshop, the result is credible.

  1. Time-Variant Reliability Analysis for Rubber O-Ring Seal Considering Both Material Degradation and Random Load

    Directory of Open Access Journals (Sweden)

    Baopeng Liao

    2017-10-01

    Full Text Available Due to the increase in working hours, the reliability of rubber O-ring seals used in hydraulic systems of transfer machines will change. While traditional methods can only analyze one of the material properties or seal properties, the failure of the O-ring is caused by these two factors together. In this paper, two factors are mainly analyzed: the degradation of material properties and load randomization by processing technology. Firstly, the two factors are defined in terms of material failure and seal failure, before the experimental methods of rubber materials are studied. Following this, the time-variant material properties through experiments and load distribution by monitoring the processing can be obtained. Thirdly, compressive stress and contact stress have been calculated, which was combined with the reliability model to acquire the time-variant reliability for the O-ring. Finally, the life prediction and effect of oil pressure were discussed, then compared with the actual situation. The results show a lifetime of 12 months for the O-ring calculated in this paper, and compared with the replacement records from the maintenance workshop, the result is credible.

  2. Predictive characterization of aging and degradation of reactor materials in extreme environments. Final report, December 20, 2013 - September 20, 2017

    Energy Technology Data Exchange (ETDEWEB)

    Qu, Jianmin [Northwestern Univ., Evanston, IL (United States)

    2017-09-20

    Understanding of reactor material behavior in extreme environments is vital not only to the development of new materials for the next generation nuclear reactors, but also to the extension of the operating lifetimes of the current fleet of nuclear reactors. To this end, this project conducted a suite of unique experimental techniques, augmented by a mesoscale computational framework, to understand and predict the long-term effects of irradiation, temperature, and stress on material microstructures and their macroscopic behavior. The experimental techniques and computational tools were demonstrated on two distinctive types of reactor materials, namely, Zr alloys and high-Cr martensitic steels. These materials are chosen as the test beds because they are the archetypes of high-performance reactor materials (cladding, wrappers, ducts, pressure vessel, piping, etc.). To fill the knowledge gaps, and to meet the technology needs, a suite of innovative in situ transmission electron microscopy (TEM) characterization techniques (heating, heavy ion irradiation, He implantation, quantitative small-scale mechanical testing, and various combinations thereof) were developed and used to elucidate and map the fundamental mechanisms of microstructure evolution in both Zr and Cr alloys for a wide range environmental boundary conditions in the thermal-mechanical-irradiation input space. Knowledge gained from the experimental observations of the active mechanisms and the role of local microstructural defects on the response of the material has been incorporated into a mathematically rigorous and comprehensive three-dimensional mesoscale framework capable of accounting for the compositional variation, microstructural evolution and localized deformation (radiation damage) to predict aging and degradation of key reactor materials operating in extreme environments. Predictions from this mesoscale framework were compared with the in situ TEM observations to validate the model.

  3. Viability of calcifying bacterial formulations in fly ash for applications in building materials.

    Science.gov (United States)

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

    2013-12-01

    Evidence of bacterial involvement in precipitation of calcium carbonates has brought a revolution in the field of applied microbiology, geotechnical sciences, environmental and civil engineering with its marked success in restoration of various building materials. For applications of these calcite binder-producing bacterial cultures, different expensive carrier materials have been used but their high costs have come in the way of their successful commercialization. In the present study, we have explored the potential of cheap industrial by-product fly ash as a carrier material for bacterial cells and investigated the viability of calcifying bacterial isolates: Bacillus megaterium, Bacillus cereus, and Lysinibacillus fusiformis in fly ash carrier at varying temperatures and moisture conditions along with biomineralization efficacy of these formulations. We used laser scanning confocal microscopy to analyze the viability of bacteria by florescent dye 5-cyano-2,3-ditolyl tetrazolium chloride (CTC) along with the plate count method. Results revealed that fly ash successfully served as an effective carrier material and bacterial formulations stored at 4 °C provided longer shelf life than those stored at higher temperatures. Up to 10(6) cfu/g was found to sustain in all formulations at 4 °C compared to 10(4)-10(5) cfu/g in case of higher temperatures up to 1 year. For 4 °C, higher moistures (50 %) were found to provide better survivability while for higher temperatures, lower moistures (30 %) favored higher viability. The biomineralization capability of fresh and formulated bacterial cells was compared on the basis of precipitation of carbonates and it was found that carbonate precipitation efficacy of formulated bacterial cells was comparable to fresh bacterial cells.

  4. Task 1. Monitoring real time materials degradation. NRC extended In-situ and real-time Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Bakhtiari, Sasan [Argonne National Lab. (ANL), Argonne, IL (United States)

    2012-03-01

    The overall objective of this project was to perform a scoping study to identify, in concert with the nuclear industry, those sensors and techniques that have the most promising commercial viability and fill a critical inspection or monitoring need. Candidates to be considered include sensors to monitor real-time material degradation, characterize residual stress, monitor and inspect component fabrication, assess radionuclide and associated chemical species concentrations in ground water and soil, characterize fuel properties, and monitor severe accident conditions. Under Task 1—Monitoring Real-Time Materials Degradation—scoping studies were conducted to assess the feasibility of potential inspection and monitoring technologies (i.e., a combination of sensors, advanced signal processing techniques, and data analysis methods) that could be utilized in LWR and/or advanced reactor applications for continuous monitoring of degradation in-situ. The goal was to identify those techniques that appear to be the most promising, i.e., those that are closest to being both technically and commercially viable and that the nuclear industry is most likely to pursue. Current limitations and associated issues that must be overcome before commercial application of certain techniques have also been addressed.

  5. Adaptive coupling between damage mechanics and peridynamics: a route for objective simulation of material degradation up to complete failure

    KAUST Repository

    Han, Fei

    2016-05-17

    The objective (mesh-independent) simulation of evolving discontinuities, such as cracks, remains a challenge. Current techniques are highly complex or involve intractable computational costs, making simulations up to complete failure difficult. We propose a framework as a new route toward solving this problem that adaptively couples local-continuum damage mechanics with peridynamics to objectively simulate all the steps that lead to material failure: damage nucleation, crack formation and propagation. Local-continuum damage mechanics successfully describes the degradation related to dispersed microdefects before the formation of a macrocrack. However, when damage localizes, it suffers spurious mesh dependency, making the simulation of macrocracks challenging. On the other hand, the peridynamic theory is promising for the simulation of fractures, as it naturally allows discontinuities in the displacement field. Here, we present a hybrid local-continuum damage/peridynamic model. Local-continuum damage mechanics is used to describe “volume” damage before localization. Once localization is detected at a point, the remaining part of the energy is dissipated through an adaptive peridynamic model capable of the transition to a “surface” degradation, typically a crack. We believe that this framework, which actually mimics the real physical process of crack formation, is the first bridge between continuum damage theories and peridynamics. Two-dimensional numerical examples are used to illustrate that an objective simulation of material failure can be achieved by this method.

  6. Survey of the degradation modes of candidate materials for high-level radioactive waste disposal containers. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Vinson, D.W.; Bullen, D.B. [Iowa State Univ. of Science and Technology, Ames, IA (United States)

    1995-09-22

    One of the most significant factors impacting the performance of waste package container materials under repository relevant conditions is the thermal environment. This environment will be affected by the areal power density of the repository, which is dictated by facility design, and the dominant heat transfer mechanism at the site. The near-field environment will evolve as radioactive decay decreases the thermal output of each waste package. Recent calculations (Buscheck and Nitao, 1994) have addressed the importance of thermal loading conditions on waste package performance at the Yucca Mountain site. If a relatively low repository thermal loading design is employed, the temperature and relative humidity near the waste package may significantly affect the degradation of corrosion allowance barriers due to moist air oxidation and radiolytically enhanced corrosion. The purpose this report is to present a literature review of the potential degradation modes for moderately corrosion resistant nickel copper and nickel based candidate materials that may be applicable as alternate barriers for the ACD systems in the Yucca Mountain environment. This report presents a review of the corrosion of nickel-copper alloys, summaries of experimental evaluations of oxidation and atmospheric corrosion in nickel-copper alloys, views of experimental studies of aqueous corrosion in nickel copper alloys, a brief review of galvanic corrosion effects and a summary of stress corrosion cracking in these alloys.

  7. Analysis of microscopic degradation and nonlinear elastic wave in nuclear structural materials

    Energy Technology Data Exchange (ETDEWEB)

    Jhang, Kyung Young; Lee, Tae Hun; Choi, Ik Hwang; Baek, Seung Hyun [Hanyang University, Seoul (Korea, Republic of)

    2010-02-15

    - Semi-automatic system configuration evaluating nonlinear characteristics of elastic wave by measuring the magnitude of higher harmonics generated after transmission of narrow band tone burst wave - Maximizing the stability of repeat measurement by finding condition of optimum pressure and induced voltage able to minimize additional nonlinearity caused by unstable contact between transducer and specimen - Establishing solution and investigation of minimizing nonlinearity depending on the system - System improvement of ultrasonic transmission and receiving - Configuration of nonlinear parameters with fatigue damage (rotary bending fatigue of SUS316L) - Configuration of nonlinear parameters with fatigue damage (tension fatigue of plate type specimen) - Experiment of nonlinear parameter with respect to microscopic degradation (grain size and precipitate volume) through various heat treatment of SA508 Gr. 3

  8. Application of Titanium Dioxide-Graphene Composite Material for Photocatalytic Degradation of Alkylphenols

    Directory of Open Access Journals (Sweden)

    Chanbasha Basheer

    2013-01-01

    Full Text Available Titanium dioxide-graphene (TiO2-G composite was used for the photodegradation of alkylphenols in wastewater samples. The TiO2-G composites were prepared via sonochemical and calcination methods. The synthesized composite was characterized by X-ray diffraction (XRD, infrared spectroscopy (IR, scanning electron microscopy (SEM, transmission electron microscopy (TEM, energy dispersive X-ray analysis (EDX, and fluorescence spectroscopy. The photocatalytic efficiency was evaluated by studying the degradation profiles of alkylphenols using gas chromatography-flame ionization detector (GC-FID. It was found that the synthesized TiO2-G composites exhibit enhanced photocatalytic efficiencies as compared to pristine TiO2. The presence of graphene not only provides a large surface area support for the TiO2 photocatalyst, but also stabilizes charge separation by trapping electrons transferred from TiO2, thereby hindering charge transfer and enhancing its photocatalytic efficiency.

  9. Effects on perceived air quality and symptoms of exposure to microbially produced metabolites and compounds emitted from damp building materials.

    Science.gov (United States)

    Claeson, A-S; Nordin, S; Sunesson, A-L

    2009-04-01

    This work investigated perceived air quality and health effects from exposure to low to high levels of volatile organic compounds (VOCs) emitted from damp building materials and a mixture of molds growing on the materials. A mixture of Wallemia sebi, Fusarium culmorum, Penicillium chrysogenum, Ulocladium botrytis, and Aspergillus versicolor was inoculated on pine wood and particle board. In Study 1, each of 27 participants took part in two exposure conditions, one with air from molds growing on building materials (low levels of emissions from the building materials and the mold mixture) and one with blank air, both conditions during 60 min. In Study 2, each of 24 participants was exposed (10 min) four times in a 2 x 2 design randomly to air from moldy building materials (high levels) and blank, with and without nose-clip. The participants rated air quality and symptoms before, during, and after each exposure. Self-reported tear-film break-up time and attention and processing speed (Study 1) was also measured. Exposure to high VOC levels increased the reports of perceived poor air quality, and in the condition without nose-clip enhanced skin symptoms were also noted. No such outcome was observed when exposing the participants to low VOC levels. Emissions from building materials caused by dampness and microbial growth may be involved in indoor air health problems. This study showed that exposure to high levels of VOC emitted from damp building materials and a mixture of mold may cause perceived poor air quality. It also indicated that stimulation of chemical warning systems (the nasal chemosensory part of the trigeminal system and the olfactory system) may enhance skin symptoms.

  10. Effect of common building materials in narrow shaped X-ray fields transmission

    Science.gov (United States)

    Vlachos, I.; Tsantilas, X.; Fountos, G.; Delis, H.; Kandarakis, I.; Panayiotakis, G.

    2015-09-01

    Diagnostic and interventional radiology, are an essential part of present day medical practice. Advances in X-ray imaging technology, together with developments in digital imaging have had a significant impact on the practice of radiology. This includes improvement in image quality, reduction in dose and a broader range of available applications resulting to better patient diagnosis and treatment. X-rays have the potential for damaging healthy cells and tissues, therefore all medical procedures employing X-ray equipment must be carefully managed. In all facilities and for all equipment types, procedures must be in place in order to ensure that exposures to patients, staff and the public are kept as low as reasonably achievable. Commonly used construction materials such as, ceramic tiles and plasterboards can provide a certain degree of protection against X-radiation. In this study, the secondary radiation transmission through common building materials is investigated, in the case of narrow shaped X-ray fields. Double plasterboard and double reinforced in thickness ceramic tile provided better radiation protection results.

  11. Covalent Organic Framework Material bearing Phloroglucinol Building Units as a Potent Anticancer Agent

    KAUST Repository

    Bhanja, Piyali

    2017-08-23

    Covalent organic frameworks (COFs) having periodicity in pores of nanoscale dimensions can be suitably designed for the organic building units bearing reactive functional groups at their surfaces. Thus, they are an attractive option as an anticancer agent to overcome the limitations of chemotherapy. Herein, we first report a new porous biodegradable nitrogen containing COF material, EDTFP-1 (ethylenedianiline-triformyl phloroglucinol), synthesized using 4,4\\'-ethylenedianiline and 2,4,6-triformylphloroglucinol via Schiff base condensation reaction. EDTFP-1 exhibited 3D-hexagonal porous structure with average pores of ca. 1.5 nm dimension. Here, we have explored the anti-cancer potentiality of EDTFP-1. Result demonstrated an enhanced cytotoxicity was observed against four cancer cells HCT 116, HepG2, A549, and MIA-Paca2 with significant lower IC50 on HCT116 cells. Additionally, EDTFP-1-induced cell death was associated with the characteristic apoptotic changes like cell membrane blebbing, nuclear DNA fragmentation, externalization of phosphatidylserine from the cell membrane followed by a loss of mitochondrial membrane potential as well as modulation of pro and anti-apoptotic proteins. Further, the result depicted a direct correlation between the generations of ROS with mitochondrial-dependant apoptosis through the involvement of p53 phosphorylation upon EDTFP-1 induction, suggesting this COF material is a novel chemotherapeutic agent for cancer treatment.

  12. Sustainable Use of Reservoir Sediment through Partial Application in Building Material

    Directory of Open Access Journals (Sweden)

    Natalia Junakova

    2017-05-01

    Full Text Available Sediment, often considered a by-product of various activities within river basin management to be disposed of, or a pollutant to be controlled, is increasingly being acknowledged as a resource in need of management. The paper deals with the possibility of reusing sediment from two Slovak reservoirs (Klusov and Ruzin as an alternative raw material in concrete production. Concrete specimens were prepared by a combination of original reservoir sediment, reservoir sediment mechanically activated by dry milling, reservoir sediment mechanically activated by dry milling together with biomass incinerator fly-ash as a binder. To improve the strength properties of specimens, sodium hydroxide (NaOH was used as a sediment activator. Mixtures containing 40% of binder replacement by the above-mentioned combinations of original and treated sediments were tested for flexural and compressive strengths after 28, 90 and 365 days of curing. The results showed that the mixtures prepared from sediments milled without and with addition of fly ash as cement replacement satisfied the strength requirements for the compressive strength class C16/20 according to the European standard except the composites prepared with NaOH as the sediment activator. Addition of NaOH into composites in the concentration of 5 M as an activator of sediment indicated the negative impact on compressive and flexural strengths and thus NaOH was not an effective pozzolanic activator for sediments. This study reveals that the sediment may be considered as 40% cement substitution in building materials.

  13. Absorption cross section of building materials at mm wavelength in a reverberation chamber

    Science.gov (United States)

    Micheli, D.; Delfini, A.; Pastore, R.; Marchetti, M.; Diana, R.; Gradoni, G.

    2017-02-01

    The reverberation chamber (RC) method is used to estimate the average absorption cross section of building materials at mm wave frequencies. Analysed samples include concrete, travertine and bricks of different types. The investigation is carried out in the frequency range between 50 GHz and 68 GHz, which is of interest in the next generation of mobile telecommunication system. A cylindrical cavity is transformed into a RC through the use of a mechanical model stirrer. The chamber field is statistically homogeneous and depolarized; therefore it can be used to probe the average response of the sample under test. In particular, through a differential measure of the average quality factor (average insertion loss) it is possible estimate the fraction of power absorbed by the sample under test. Several cube-shape samples have been characterized and compared. Obtained results show that analysed samples have remarkably different levels of the electromagnetic wave absorption, depending on both material density and chemical composition. The absorption of pure water is used as a baseline to determine the dynamic range of the measurement.

  14. Hot Plate Method with Two Simultaneous Temperature Measurements for Thermal Characterization of Building Materials

    Science.gov (United States)

    Osséni, Sibiath O. G.; Ahouannou, Clément; Sanya, Emile A.; Jannot, Yves

    2017-07-01

    This paper presents a study of the hot plate method with two simultaneous temperature measurements, on the heated and unheated faces of a sample to characterize. The thermal properties of polyvinyl chloride, plaster and laterite were considered to be a representative range of building materials. A 1D quadrupolar model was developed to represent the temperature evolution on the two faces over time. Three-dimensional numerical modeling of a quarter of the testing device with COMSOL software allowed defining the domain of the 1D hypothesis validity. The analysis of estimation possibilities of materials' thermal characteristics, with the developed method, revealed that thermal effusivity can be accurately estimated by using the temperature of the heated face at the beginning of heating. We showed that the simultaneous use of two temperatures enables the estimation of the thermal conductivity with a greater accuracy and over a shorter time interval than using the temperature of the heated face alone. We also demonstrated that under certain conditions (samples with a high ratio of thickness to width) the method with two temperature measurements enabled the estimation of the thermal effusivity and conductivity, while the method with one temperature allowed only the thermal effusivity to be estimated, because of 3D effects. This conclusion was confirmed by experimental results obtained with a mortar sample.

  15. Recycling waste brick from construction and demolition of buildings as pozzolanic materials.

    Science.gov (United States)

    Lin, Kae-Long; Wu, Hsiu-Hsien; Shie, Je-Lueng; Hwang, Chao-Lung; An Cheng

    2010-07-01

    This investigation elucidates the pozzolic characteristics of pastes that contain waste brick from building construction and demolition wastes. The TCLP leaching concentrations of waste brick for the target cations or heavy metals were all lower than the current regulatory thresholds of the Taiwan EPA. Waste brick had a pozzolanic strength activity index of 107% after 28 days. It can be regarded as a strong pozzolanic material. The compressive strengths of waste brick blended cement (WBBC) that contain 10% waste brick increased from 71.2 MPa at 28 days to 75.1 MPa at 60 days, an increase of approximately 5% over that period. At 28 days, the pozzolanic reaction began, reducing the amount of Ca(OH)(2) and increasing the densification. The intensity of the peak at 3640 cm(- 1) associated with Ca(OH)(2) is approximately the same for ordinary Portland cement (OPC) pastes. The hydration products of all the samples yield characteristics peaks at 978 cm(-1) associated with C-S-H, and at ~3011 cm(-1) and 1640 cm(-1) associated with water. The samples yield peaks at 1112 cm(-1), revealing the formation of ettringite. In WBBC pastes, the ratio Q(2)/Q(1) increases with curing time. These results demonstrate that increasing the curing time increases the number of linear polysilicate anions in C-S-H. Experimental results reveal that waste brick has potential as a pozzolanic material in the partial replacement of cement.

  16. Building waste management core indicators through Spatial Material Flow Analysis: net recovery and transport intensity indexes.

    Science.gov (United States)

    Font Vivanco, David; Puig Ventosa, Ignasi; Gabarrell Durany, Xavier

    2012-12-01

    In this paper, the material and spatial characterization of the flows within a municipal solid waste (MSW) management system are combined through a Network-Based Spatial Material Flow Analysis. Using this information, two core indicators are developed for the bio-waste fraction, the Net Recovery Index (NRI) and the Transport Intensity Index (TII), which are aimed at assessing progress towards policy-related sustainable MSW management strategies and objectives. The NRI approaches the capacity of a MSW management system for converting waste into resources through a systematic metabolic approach, whereas the TII addresses efficiency in terms of the transport requirements to manage a specific waste flow throughout the entire MSW management life cycle. Therefore, both indicators could be useful in assessing key MSW management policy strategies, such as the consecution of higher recycling levels (sustainability principle) or the minimization of transport by locating treatment facilities closer to generation sources (proximity principle). To apply this methodological approach, the bio-waste management system of the region of Catalonia (Spain) has been chosen as a case study. Results show the adequacy of both indicators for identifying those points within the system with higher capacity to compromise its environmental, economic and social performance and therefore establishing clear targets for policy prioritization. Moreover, this methodological approach permits scenario building, which could be useful in assessing the outcomes of hypothetical scenarios, thus proving its adequacy for strategic planning. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Physicochemical Properties of Handere Clays and Their Use as a Building Material

    Directory of Open Access Journals (Sweden)

    Yasin Erdoğan

    2015-01-01

    Full Text Available Handere clay deposits were discovered at Adana in Turkey. These clay units primarily consist of uncoloured claystone, pebbly sandstone, sandstone, siltstone, and mudstone marl and include gypsum lenses and clay levels of various thicknesses in places. The physicochemical properties of these clays have been investigated by different techniques including Scanning Electron and Elemental Analysis (SEM and EDS, mineralogical analyses, chemical and physical analyses, X-ray diffraction (XRD, thermogravimetric differential thermal analysis (TG-DTA, and Atterberg (Consistency Limits Test. The mineralogical composition deduced from XRD is wide (smectite + palygorskite + illite ± feldspar ± chlorite ± quartz ± calcite ± serpentine due to the high smectite contents (≈85%. SEM studies reveal that smectite minerals are composed of irregular platy leaves and show honeycomb pattern in the form of wavy leaves in places. The leaves presenting an array with surface edge contact are usually concentrated in the dissolution voids and fractures of volcanic glass. Organic matter content and loss on ignition analysis of raw materials are good for all the studied samples. In summary, Handere clays can be used as building materials in bricks, roof tiles, and cement and as a binder.

  18. Test methods and reduction of organic pollutant compound emissions from wood-based building and furniture materials.

    Science.gov (United States)

    Kim, Sumin; Choi, Yoon-Ki; Park, Kyung-Won; Kim, Jeong Tai

    2010-08-01

    This paper reviews different methods for the analysis of formaldehyde and volatile organic compounds (VOCs) from wood-based panel materials for furniture and building interiors and highlights research on reduction of emission from wood-based panels that can adversely affect indoor air quality. In Korea, standard test methods have been developed to determine formaldehyde and VOC emissions from building products, and the Ministry of Environment regulates the use of building materials with pollutant emissions. Desiccator and perforator methods are being used for formaldehyde and the chamber and field and laboratory emission cell (FLEC) methods for VOC and formaldehyde emissions. The VOC analyzer is a suitable pre-test method for application as a total VOC (TVOC) emission test and bake-out is a useful method to reduce TVOC and formaldehyde emissions from furniture materials in indoor environments. Copyright 2010 Elsevier Ltd. All rights reserved.

  19. Cellular automata modeling depicts degradation of cellulosic material by a cellulase system with single-molecule resolution.

    Science.gov (United States)

    Eibinger, Manuel; Zahel, Thomas; Ganner, Thomas; Plank, Harald; Nidetzky, Bernd

    2016-01-01

    Enzymatic hydrolysis of cellulose involves the spatiotemporally correlated action of distinct polysaccharide chain cleaving activities confined to the surface of an insoluble substrate. Because cellulases differ in preference for attacking crystalline compared to amorphous cellulose, the spatial distribution of structural order across the cellulose surface imposes additional constraints on the dynamic interplay between the enzymes. Reconstruction of total system behavior from single-molecule activity parameters is a longstanding key goal in the field. We have developed a stochastic, cellular automata-based modeling approach to describe degradation of cellulosic material by a cellulase system at single-molecule resolution. Substrate morphology was modeled to represent the amorphous and crystalline phases as well as the different spatial orientations of the polysaccharide chains. The enzyme system model consisted of an internally chain-cleaving endoglucanase (EG) as well as two processively acting, reducing and non-reducing chain end-cleaving cellobiohydrolases (CBHs). Substrate preference (amorphous: EG, CBH II; crystalline: CBH I) and characteristic frequencies for chain cleavage, processive movement, and dissociation were assigned from biochemical data. Once adsorbed, enzymes were allowed to reach surface-exposed substrate sites through "random-walk" lateral diffusion or processive motion. Simulations revealed that slow dissociation of processive enzymes at obstacles obstructing further movement resulted in local jamming of the cellulases, with consequent delay in the degradation of the surface area affected. Exploiting validation against evidence from atomic force microscopy imaging as a unique opportunity opened up by the modeling approach, we show that spatiotemporal characteristics of cellulose surface degradation by the system of synergizing cellulases were reproduced quantitatively at the nanometer resolution of the experimental data. This in turn gave

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

    Energy Technology Data Exchange (ETDEWEB)

    Gdowski, G.E.; Bullen, D.B. (Science and Engineering Associates, Inc., Pleasanton, CA (USA))

    1988-08-01

    Three copper-based alloys and three iron- to nickel-based austenitic alloys are being considered as possible materials for fabrication of containers for disposal of high-level radioactive waste. This waste will include spent fuel assemblies from reactors as well as high-level waste in borosilicate glass and will be sent to the prospective site at Yucca Mountain, Nevada, for disposal. The containers must maintain substantially complete containment for at least 300 yr and perhaps as long as 1000 yr. During the first 50 yr after emplacement, they must be retrievable from the disposal site. Shortly after the containers are emplaced in the repository, they will be exposed to high temperatures and high gamma radiation fields from the decay of the high-level waste. This volume surveys the available data on oxidation and corrosion of the iron- to nickel-based austenitic materials (Types 304L and 316L stainless steels and Alloy 825) and the copper-based alloy materials (CDA 102 (oxygen-free copper), CDA 613 (Cu-7Al), and CDA 715 (Cu-30Ni)), which are the present candidates for fabrication of the containers. Studies that provided a large amount of data are highlighted, and those areas in which little data exists are identified. Examples of successful applications of these materials are given. On the basis of resistance to oxidation and general corrosion, the austenitic materials are ranked as follows: Alloy 825 (best), Type 316L stainless steel, and then Type 304L stainless steel (worst). For the copper-based materials, the ranking is as follows: CDA 715 and CDA 613 (both best), and CDA 102 (worst). 110 refs., 30 figs., 13 tabs.

  1. Evaluation of three common green building materials for ozone removal, and primary and secondary emissions of aldehydes

    Science.gov (United States)

    Gall, Elliott; Darling, Erin; Siegel, Jeffrey A.; Morrison, Glenn C.; Corsi, Richard L.

    2013-10-01

    Ozone reactions that occur on material surfaces can lead to elevated concentrations of oxidized products in the occupied space of buildings. However, there is little information on the impact of materials at full scale, especially for green building materials. Experiments were completed in a 68 m3 climate-controlled test chamber with three certified green building materials that can cover large areas in buildings: (1) recycled carpet, (2) perlite-based ceiling tile and (3) low-VOC paint and primer on recycled drywall. Ozone deposition velocity and primary and secondary emission rates of C1 to C10 saturated carbonyls were determined for two chamber mixing conditions and three values of relative humidity. A direct comparison was made between ozone deposition velocities and carbonyl yields observed for the same materials analyzed in small (10 L) chambers. Total primary carbonyl emission rates from carpet, ceiling tile and painted drywall ranged from 27 to 120 μg m-2 h-1, 13 to 40 μg m-2 h-1, 3.9 to 42 μg m-2 h-1, respectively. Ozone deposition velocity to these three materials averaged 6.1 m h-1, 2.3 m h-1 and 0.32 m h-1, respectively. Total secondary carbonyl emissions from these materials ranged from 70 to 276 μg m-2 h-1, 0 to 12 μg m-2 h-1, and 0 to 30 μg m-2 h-1, respectively. Carbonyl emissions were determined with a transient approximation, and were found to be in general agreement with those found in the literature. These results suggest that care should be taken when selecting green building materials due to potentially large differences in primary and secondary emissions.

  2. Possible Responsibility of Silicone Materials for Degradation of the CO2 Removal System in the International Space Station

    Science.gov (United States)

    Baeza, Mario; Sharma, Hemant; Borrok, David; Ren, Mingua; Pannell, Keith

    2011-01-01

    From data concerning the degradation of the CO2 removal system in the International Space Station (ISS) two important features were apparent: (1) The atmosphere within the International Space Station (ISS) contained many organic compounds including alcohols, halocarbons, aldehydes, esters, and ketones, inter alia. Various cyclosiloxanes Dn, hexamethylcyclotrisiloxane (D3) and its higher homologs (D4) and (D5) are also present presumably due to offgassing. (2) Screens within the zeolite-containing canisters, used for the removal of CO2, exhibited partial clogging due to zeolitic fragments (dust) along with "sticky" residues, that in toto significantly reduced the efficiency of the CO2 removal process. Samples of the ISS fresh zeolite, used zeolite, filter clogging zeolite particles and residual polymeric materials were examined using, inter alia, NMR, EM and HRSEM. These data were compared to equivalent samples obtained prior and subsequent to Dn polymerization experiments performed in our laboratories using the clean ISS zeolite samples as catalyst. Polysiloxane materials produced were essentially equivalent in the two cases and the EM images demonstrate a remarkable similarity between the ISS filter zeolite samples and the post-polymerization zeolite material from our experiments. In this regard even the changes in the Al/Si ratio from the virgin zeolite material to the filter samples and the post-polymerization laboratory samples samples is noteworthy. This research was supported by a contract from the Boeing Company

  3. TRUE COLORS: LEDS AND THE RELATIONSHIP BETWEEN CCT, CRI, OPTICAL SAFETY, MATERIAL DEGRADATION, AND PHOTOBIOLOGICAL STIMULATION

    Energy Technology Data Exchange (ETDEWEB)

    Royer, Michael P.

    2014-08-30

    This document analyzes the optical, material, and photobiological hazards of LED light sources compared to conventional light sources. It documents that LEDs generally produce the same amount of blue light, which is the primary contributor to the risks, as other sources at the same CCT. Duv may have some effect on the amount of blue light, but CRI does not.

  4. 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

    Thin dense membrane layers, mechanically supported by porous substrates, are considered as the most efficient designs for oxygen supply units used in Oxy-fuel processes and membrane reactors. Based on the favorable permeation properties and chemical stability, several materials were suggested...

  5. Nanoenhanced Materials for Reclamation of Mine Lands and Other Degraded Soils: A Review

    Directory of Open Access Journals (Sweden)

    Ruiqiang Liu

    2012-01-01

    Full Text Available Successful mine soil reclamation facilitates ecosystem recovery, minimizes adverse environmental impacts, creates additional lands for agricultural or forestry uses, and enhances the carbon (C sequestration. Nanoparticles with extremely high reactivity and deliverability can be applied as amendments to improve soil quality, mitigate soil contaminations, ensure safe land–application of the conventional amendment materials (e.g., manures and biosolids, and enhance soil erosion control. However, there is no report on using nanoenhanced materials for mine soil reclamation. Through reviewing the up-to-date research results on using environment-friendly nanoparticles for agricultural soil quality improvement and for contaminated soil remediation, this paper synthesizes that these nanomaterials with high potentials for mine soil reclamation include zeolites, zero-valent iron nanoparticles, iron oxide nanoparticles, phosphate-based nanoparticles, iron sulfide nanoparticles and C nanotubes. Transport of these particles in the environment and their possible ecotoxicological effects are also discussed. Additionally, this article proposes a practical and economical approach to applying nanotechnology for mine soil reclamation: adding small amounts of nanoparticles to the conventional soil amendment materials and then applying the mixtures for soil quality improvements. Hence the cost of using nanoparticles is reduced and the benefits of both nanoparticles and the conventional amendment materials are harnessed.

  6. Improvement of operational properties of shell limestone building materials by polysulfide solution impregnation

    Directory of Open Access Journals (Sweden)

    MASSALIMOV Ismail Alexandrovich

    2017-06-01

    Full Text Available The data of studies on the effectiveness of impregnation with polysulfide solutions of shell limestone used as facing and wall material, as well as for the manufacture of road products are presented. Modification of the limestone with the impregnating composition «Akvastat» created by the authors which is sulfur-containing water-based solution of calcium polysulfide containing alcohols and surfactants, can significantly reduce water absorption and increase durability of limestone. Impregnating composition on the basis of calcium polysulfide possesses density of 1.22–1.24 g/cm3, the infiltrant penetrates into the pore structure of limestone to a depth of 4 cm or more, depending on the density and structure of the sample. While the material is drying, sulfur nanoparticles are crystallized from the polysulfide solution in its pores. They partially fill pore space and form protective durable insoluble hydrophobic coating that impedes the penetration of water into the pores of the limestone, but preserves its vapor permeability, which is important for wall and decoration materials. The evaluation of protective coatings was performed with laser particle size analyzer, scanning probe microscope and a diffractometer. It showed that the average size of the particles forming the protective coating is in the range of 20–25 nm, the particles shape is spherical, the particles are elemental sulfur with orthorhombic structure of the crystal lattice. The processing of shell limestone with calcium polysulphide solution provides formation of coating based on nanosized sulfur on the surface of stone pores. The coating partially fills the pore space and, as it is hydrophobic, reduces the water absorption of the samples by a factor of 5–8, increases their average density by 22–27%, strength in 1,2–1,3 times, the softening factor by 6–19%, that makes possible to predict the increase of the durability of building materials based on shell limestone to 1

  7. Phase Change Materials (PCMs) applications in buildings for human thermal comfort

    CSIR Research Space (South Africa)

    Kumirai, Tichaona

    2016-10-01

    Full Text Available end-use contribution to energy consumption especially in commercial buildings (includes office buildings, shopping centers, restaurants, and others) is from Heating, Ventilation and Air conditioning (HVAC) accounting as much as 26% of the total energy...

  8. Straw bale: A Waste from Agriculture, a New Construction Material for Sustainable Buildings

    National Research Council Canada - National Science Library

    Chaussinand, Adrien; Scartezzini, J.L; Nik, Vahid

    2015-01-01

    .... Thermal-dynamic results and Life Cycle Assessment conclude that straw bale buildings can be a sustainable alternative in the energy evolution of building construction, due to its low embodied energy...

  9. Effect of polyethelene oxide on the thermal degradation of cellulose biofilm - Low cost material for soft tissue repair in dentistry.

    Science.gov (United States)

    Akkus, Anna; Tyler, Rakim; Schiraldi, David; Roperto, Renato; Faddoul, Fady; Teich, Sorin

    2017-07-01

    Bio cellulose is a byproduct of sweet tea fermentation known as kombusha. During the biosynthesis by bacteria cellulose chains are polymerized by enzyme from activated glucose. The single chains are then extruded through the bacterial cell wall. Interestingly, a potential of the Kombucha's byproduct bio cellulose (BC) as biomaterial had come into focus only in the past few decades. The unique physical and mechanical properties such as high purity, an ultrafine and highly crystalline network structure, a superior mechanical strength, flexibility, pronounced permeability to gases and liquids, and an excellent compatibility with living tissue that reinforced by biodegradability, biocompatibility, large swelling ratios. The bio-cellulose film specimens were provided by the R.P Dressel dental materials laboratory, Department of Comprehensive Care, School of Dental Medicine, Case Western Reserve University, Cleveland, US. The films were harvested, washed with water and dried at room temperature overnight. 1wt% of PEG-2000 and 10wt% of NaOH were added into ultrapure water to prepare PEG/NaOH solution. Then bio-cellulose film was added to the mixture and swell for 3 h at room temperature. All bio-cellulose film specimens were all used in the TA Instruments Q500 Thermogravmetric Analyzer to investigate weight percent lost and degradation. The TGA was under ambient air conditions at a heating rate of 10ºC/min. PEG control exhibited one transition with the peak at 380ºC. Cellulose and cellulose/ PEG films showed 3 major transitions. Interestingly, the cellulose/PEG film showed slightly elevated temperatures when compared to the corresponding transitions for cellulose control. The thermal gravimetric analysis (TGA) degradation curves were analyzed. Cellulose control film exhibited two zero order transitions, that indicate the independence of the rate of degradation from the amount on the initial substance. The activation energies for three transitions for cellulose and

  10. Digital Learning Material for Student-Directed Model Building in Molecular Biology

    Science.gov (United States)

    Aegerter-Wilmsen, Tinri; Coppens, Marjolijn; Janssen, Fred; Hartog, Rob; Bisseling, Ton

    2005-01-01

    The building of models to explain data and make predictions constitutes an important goal in molecular biology research. To give students the opportunity to practice such model building, two digital cases had previously been developed in which students are guided to build a model step by step. In this article, the development and initial…

  11. Applications of clay as a building material. Der Baustoff Lehm und seine Anwendung

    Energy Technology Data Exchange (ETDEWEB)

    Minke, G.

    1984-01-01

    This book is the first in a series on the subject of building with clay. The first part contains contributions from various authors who deal with the properties of clay. They also treat practical building with clay (light weight clay ceilings, clay stoves, clay domes, the thin clay-loaf method). The historical contributions present historical clay buildings in Schleswig Holstein. (BWI).

  12. Wood and Other Materials Used to Construct Nonresidential Buildings in the United States 2011

    Science.gov (United States)

    Craig Adair; David B. McKeever; Chris Gaston; Margaret. Stewart

    2013-01-01

    The construction of low-rise nonresidential buildings is an important market for lumber, engineered wood products, and structural and nonstructural wood panels in the United States. This report examines low-rise nonresidential buildings of six or fewer stories. Those with more than six stories are normally severely restricted by building codes from being wood framed....

  13. Wood and Other Materials Used to Construct Nonresidential Buildings in the United States 2011 Executive Summary

    Science.gov (United States)

    David B. McKeever

    2013-01-01

    The construction of low-rise nonresidential buildings is an important market for lumber, engineered wood products, and structural and nonstructural wood panels in the United States. This report examines low-rise nonresidential buildings of six or fewer stories. Those with more than six stories are normally severely restricted by building codes from being wood framed....

  14. Maintenance and Expansion: Modeling Material Stocks and Flows for Residential Buildings and Transportation Networks in the EU25.

    Science.gov (United States)

    Wiedenhofer, Dominik; Steinberger, Julia K; Eisenmenger, Nina; Haas, Willi

    2015-08-01

    Material stocks are an important part of the social metabolism. Owing to long service lifetimes of stocks, they not only shape resource flows during construction, but also during use, maintenance, and at the end of their useful lifetime. This makes them an important topic for sustainable development. In this work, a model of stocks and flows for nonmetallic minerals in residential buildings, roads, and railways in the EU25, from 2004 to 2009 is presented. The changing material composition of the stock is modeled using a typology of 72 residential buildings, four road and two railway types, throughout the EU25. This allows for estimating the amounts of materials in in-use stocks of residential buildings and transportation networks, as well as input and output flows. We compare the magnitude of material demands for expansion versus those for maintenance of existing stock. Then, recycling potentials are quantitatively explored by comparing the magnitude of estimated input, waste, and recycling flows from 2004 to 2009 and in a business-as-usual scenario for 2020. Thereby, we assess the potential impacts of the European Waste Framework Directive, which strives for a significant increase in recycling. We find that in the EU25, consisting of highly industrialized countries, a large share of material inputs are directed at maintaining existing stocks. Proper management of existing transportation networks and residential buildings is therefore crucial for the future size of flows of nonmetallic minerals.

  15. Organophosphorus Flame Retardants and Plasticizers in Building and Decoration Materials and Their Potential Burdens in Newly Decorated Houses in China.

    Science.gov (United States)

    Wang, Yan; Hou, Minmin; Zhang, Qiaonan; Wu, Xiaowei; Zhao, Hongxia; Xie, Qing; Chen, Jingwen

    2017-10-03

    Organophosphorus flame retardants (OPFRs) have been increasingly used in various building and decoration materials to fulfill fire safety standards since the phasing out of polybrominated diphenyl ethers. We determined OPFR concentrations in the most commonly used building and decoration materials available in local markets and online in China. The OPFR concentrations varied significantly, from 14.78 ng/g (putty powder) to 9649000 ng/g (expanded polystyrene panel (EPS)). Relatively high concentrations of OPFRs were found in foam samples, followed by nonwoven and polyvinyl chloride (PVC) wallpaper, PVC pipes, sealing materials, boards, and paints. Low concentrations were found mostly in wall decoration powders, suggesting that no OPFRs had been added to these powders. Tris(1-chloro-2-propyl) phosphate and tris(1,3-dichloro-2-propyl) phosphate were the most detected halogenated OPFRs, while tri-n-butyl phosphate and tris(2-butoxyethyl) phosphate were the dominant nonhalogenated OPFRs, implying that they are commonly used in building and decoration materials. The estimated OPFR burden in interior decoration using nonwoven wallpaper was 330- and 2110-fold higher than that using latex paint and diatomite, respectively. The emission periods of OPFRs from nonwoven and PVC wallpaper may be greater than 13 years. We estimated that the total burden of OPFRs for decoration using wallpaper in newly decorated houses in China is ∼63 t/y. Significantly higher concentrations of OPFRs in interior decoration materials, especially nonwoven wallpaper, pose potential health risks to the people using the buildings.

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

    Energy Technology Data Exchange (ETDEWEB)

    Vinson, D.W.; Nutt, W.M.; Bullen, D.B. [Iowa State Univ. of Science and Technology, Ames, IA (United States)

    1995-06-01

    Oxidation and atmospheric corrosion data suggest that addition of Cr provides the greatest improvement in oxidation resistance. Cr-bearing cast irons are resistant to chloride environments and solutions containing strongly oxidizing constituents. Weathering steels, including high content and at least 0.04% Cu, appear to provide adequate resistance to oxidation under temperate conditions. However, data from long-term, high-temperature oxidation studies on weathering steels were not available. From the literature, it appears that the low alloy steels, plain carbon steels, cast steels, and cast irons con-ode at similar rates in an aqueous environment. Alloys containing more than 12% Cr or 36% Ni corrode at a lower rate than plain carbon steels, but pitting may be worse. Short term tests indicate that an alloy of 9Cr-1Mo may result in increased corrosion resistance, however long term data are not available. Austenitic cast irons show the best corrosion resistance. A ranking of total corrosion performance of the materials from most corrosion resistant to least corrosion resistant is: Austenitic Cast Iron; 12% Cr = 36% Ni = 9Cr-1Mo; Carbon Steel = Low Alloy Steels; and Cast Iron. Since the materials to be employed in the Advanced Conceptual Design (ACD) waste package are considered to be corrosion allowance materials, the austenitic cast irons, high Cr steels, high Ni steels and the high Cr-Mo steels should not be considered as candidates for the outer containment barrier. Based upon the oxidation and corrosion data available for carbon steels, low alloy steels, and cast irons, a suitable list of candidate materials for a corrosion allowance outer barrier for an ACD waste package could include, A516, 2.25%Cr -- 1%Mo Steel, and A27.

  17. The Thermochemical Degradation of Hot Section Materials for Gas Turbine Engines in Alternative-Fuel Combustion Environments

    Science.gov (United States)

    Montalbano, Timothy

    Gas turbine engines remain an integral part of providing the world's propulsion and power generation needs. The continued use of gas turbines requires increased temperature operation to reach higher efficiencies and the implementation of alternative fuels for a lower net-carbon footprint. This necessitates evaluation of the material coatings used to shield the hot section components of gas turbines in these new extreme environments in order to understand how material degradation mechanisms change. Recently, the US Navy has sought to reduce its use of fossil fuels by implementing a blended hydroprocessed renewable diesel (HRD) derived from algae in its fleet. To evaluate the material degradation in this alternative environment, metal alloys are exposed in a simulated combustion environment using this blended fuel or the traditional diesel-like fuel. Evaluation of the metal alloys showed the development of thick, porous scales with a large depletion of aluminum for the blend fuel test. A mechanism linking an increased solubility of the scale to the blend fuel test environment will be discussed. For power generation applications, Integrated Gasification Combined Cycle (IGCC) power plants can provide electricity with 45% efficiency and full carbon capture by using a synthetic gas (syngas) derived from coal, biomass, or another carbon feedstock. However, the combustion of syngas is known to cause high water vapor content levels in the exhaust stream with unknown material consequences. To evaluate the effect of increased humidity, air-plasma sprayed (APS), yttria-stabilized zirconia (YSZ) is thermally aged in an environment with and without humidity. An enhanced destabilization of the parent phase by humid aging is revealed by x-ray diffraction (XRD) and Raman spectroscopy. Microstructural analysis by transmission electron microscopy (TEM) and scanning-TEM (STEM) indicate an enhanced coarsening of the domain structure of the YSZ in the humid environment. The enhanced

  18. Photocatalytic degradation of an azo-dye on TiO2/activated carbon composite material.

    Science.gov (United States)

    Andriantsiferana, C; Mohamed, E F; Delmas, H

    2014-01-01

    A sequential adsorption/photocatalytic regeneration process to remove tartrazine, an azo-dye in aqueous solution, has been investigated. The aim ofthis work was to compare the effectiveness of an adsorbent/photocatalyst composite-TiO2 deposited onto activated carbon (AC) - and a simple mixture of powders of TiO2 and AC in same proportion. The composite was an innovative material as the photocatalyst, TiO2, was deposited on the porous surface ofa microporous-AC using metal-organic chemical vapour deposition in fluidized bed. The sequential process was composed of two-batch step cycles: every cycle alternated a step of adsorption and a step of photocatalytic oxidation under ultra-violet (365 nm), at 25 degreeC and atmospheric pressure. Both steps, adsorption and photocatalytic oxidation, have been investigated during four cycles. For both materials, the cumulated amounts adsorbed during four cycles corresponded to nearly twice the maximum adsorption capacities qmax proving the photocatalytic oxidation to regenerate the adsorbent. Concerning photocatalytic oxidation, the degree of mineralization was higher with the TiO2/AC composite: for each cycle, the value of the total organic carbon removal was 25% higher than that obtained with the mixture powder. These better photocatalytic performances involved better regeneration than higher adsorbed amounts for cycles 2, 3 and 4. Better performances with this promising material - TiO2 deposited onto AC - compared with TiO2 powder could be explained by the vicinity of photocatalytic and AC adsorption sites.

  19. Instabilities of Damage and Surface Degradation Mechanisms in Brittle Material Structural Systems

    Science.gov (United States)

    1992-03-15

    of (4.16) is lengthy, at the peak aOau /Or = 0 and this simplifies the calculations significantly. Relation (4.16) after algebraic manipulations...what conditions stability at the peak strength is possible. First we examine the case where the two material fractions are assumed lineas and elastic...umpniou. We cousider t= the rn=-al is linea elastic and isotropic. This, of course r sent a ’sti’er’aterial than acal rock Fig. 4. Gimetry of a

  20. Host cell capable of producing enzymes useful for degradation of lignocellulosic material

    Science.gov (United States)

    Los, Alrik Pieter; Sagt, Cornelis Maria Jacobus; Schooneveld-Bergmans, Margot Elisabeth Francoise; Damveld, Robbertus Antonius

    2015-08-18

    The invention relates to a host cell comprising at least four different heterologous polynucleotides chosen from the group of polynucleotides encoding cellulases, hemicellulases and pectinases, wherein the host cell is capable of producing the at least four different enzymes chosen from the group of cellulases, hemicellulases and pectinases, wherein the host cell is a filamentous fungus and is capable of secretion of the at least four different enzymes. This host cell can suitably be used for the production of an enzyme composition that can be used in a process for the saccharification of cellulosic material.

  1. Host cell capable of producing enzymes useful for degradation of lignocellulosic material

    Energy Technology Data Exchange (ETDEWEB)

    Los, Alrik Pieter; Sagt, Cornelis Maria Jacobus; Schoonneveld-Bergmans, Margot Elisabeth Francoise; Damveld, Robbertus Antonius

    2017-08-22

    The invention relates to a host cell comprising at least four different heterologous polynucleotides chosen from the group of polynucleotides encoding cellulases, hemicellulases and pectinases, wherein the host cell is capable of producing the at least four different enzymes chosen from the group of cellulases, hemicellulases and pectinases, wherein the host cell is a filamentous fungus and is capable of secretion of the at least four different enzymes. This host cell can suitably be used for the production of an enzyme composition that can be used in a process for the saccharification of cellulosic material.

  2. Implications of Steam Generator Fouling on the Degradation of Material and Thermal Performance

    Science.gov (United States)

    Turner, Carl W.

    Fouling of steam generators has a significant negative impact on the material and thermal performance the steam generators of pressurized water reactors. Corrosion products that originate from various components in the steam cycle of a nuclear power plant get pumped forward with the feed water to steam generators where they deposit on the tube bundle, tube support structure and the tube sheet. Heavy accumulation of deposit within the steam generator has led to some serious operational problems, including loss of thermal performance, under deposit corrosion, steam generator level oscillations, flow accelerated corrosion of carbon steel tube support plates and the failure of steam generator tubes due to high cycle fatigue.

  3. Building waste management core indicators through Spatial Material Flow Analysis: Net recovery and transport intensity indexes

    Energy Technology Data Exchange (ETDEWEB)

    Font Vivanco, David, E-mail: font@cml.leidenuniv.nl [Institut de Ciencia i Tecnologia Ambientals (ICTA), Departament d' Enginyeria Quimica, Universitat Autonoma de Barcelona (UAB), 08193 Bellaterra, Barcelona (Spain); Institute of Environmental Sciences (CML), Leiden University, P.O. Box 9518, 2300 RA Leiden (Netherlands); Puig Ventosa, Ignasi [ENT Environment and Management, Carrer Sant Joan 39, First Floor, 08800 Vilanova i la Geltru, Barcelona (Spain); Gabarrell Durany, Xavier [Institut de Ciencia i Tecnologia Ambientals (ICTA), Departament d' Enginyeria Quimica, Universitat Autonoma de Barcelona (UAB), 08193 Bellaterra, Barcelona (Spain)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer Sustainability and proximity principles have a key role in waste management. Black-Right-Pointing-Pointer Core indicators are needed in order to quantify and evaluate them. Black-Right-Pointing-Pointer A systematic, step-by-step approach is developed in this study for their development. Black-Right-Pointing-Pointer Transport may play a significant role in terms of environmental and economic costs. Black-Right-Pointing-Pointer Policy action is required in order to advance in the consecution of these principles. - Abstract: In this paper, the material and spatial characterization of the flows within a municipal solid waste (MSW) management system are combined through a Network-Based Spatial Material Flow Analysis. Using this information, two core indicators are developed for the bio-waste fraction, the Net Recovery Index (NRI) and the Transport Intensity Index (TII), which are aimed at assessing progress towards policy-related sustainable MSW management strategies and objectives. The NRI approaches the capacity of a MSW management system for converting waste into resources through a systematic metabolic approach, whereas the TII addresses efficiency in terms of the transport requirements to manage a specific waste flow throughout the entire MSW management life cycle. Therefore, both indicators could be useful in assessing key MSW management policy strategies, such as the consecution of higher recycling levels (sustainability principle) or the minimization of transport by locating treatment facilities closer to generation sources (proximity principle). To apply this methodological approach, the bio-waste management system of the region of Catalonia (Spain) has been chosen as a case study. Results show the adequacy of both indicators for identifying those points within the system with higher capacity to compromise its environmental, economic and social performance and therefore establishing clear targets for policy

  4. The advantage of selection of mineral thermal insulation materials with the structural properties for thermal insulation in buildings

    Directory of Open Access Journals (Sweden)

    Janžekovič Ines M.

    2014-01-01

    Full Text Available The paper deals with the problem of energy efficiency in Serbia. It gives a general overview of the energy losses and focuses on energy losses in buildings, which is recognized as one of the most problematic sectors as the energy losses concerns. By the very fact there is a need for more efficient implementation of measures to reduce energy losses through education and increased awareness of citizens about the proper ways of performing thermal protection of buildings. The paper points out the problems that arise when selecting the inadequate solutions of performing thermal insulation of buildings and suggests some solutions for the proper selection of materials for thermal insulation and in setting the appropriate requirements for thermal envelope for buildings.

  5. Predictive modeling of composite material degradation using piezoelectric wafer sensors electromechanical impedance spectroscopy

    Science.gov (United States)

    Gresil, Matthieu; Yu, Lingyu; Sutton, Mike; Guo, Siming; Pollock, Patrick

    2012-04-01

    The advancement of composite materials in aircraft structures has led to on increased need for effective structural health monitoring (SHM) technologies that are able to detect and assess damage present in composites structures. The work presented in this paper is interested in understanding using self-sensing piezoelectric wafer active sensors (PWAS) to conduct electromechanical impedance spectroscopy (EMIS) in glass fiber reinforced plastic (GFRP) to perform structures health monitoring. PWAS are bonded to the composite material and the EMIS method is used to analyze the changes in the structural resonance and anti-resonance. As the damage progresses in the specimen, the impedance spectrum will change. In addition, multi-physics based finite element method (MP-FEM) is used to model the electromechanical behavior of a free PWAS and its interaction with the host structure on which it is bonded. The MPFEM permits the input and the output variables to be expressed directly in electric terms while the two way electromechanical conversion is done internally in the MP_FEM formulation. To reach the goal of using the EMIS approach to detect damage, several damages models are generated on laminated GFRP structures. The effects of the modeling are carefully studied through experimental validation. A good match has been observed for low and very high frequencies.

  6. Degradation of FEP thermal control materials returned from the Hubble Space Telescope

    Science.gov (United States)

    Zuby, Thomas M.; Degroh, Kim K.; Smith, Daniela C.

    1995-01-01

    After an initial 3.6 years of space flight, the Hubble Space Telescope was serviced through a joint effort with the NASA and the European Space Agency. Multi-layer insulation (MLI) was retrieved from the electronics boxes of the two magnetic sensing systems (MSS), also called the magnetometers, and from the returned solar array (SA-I) drive arm assembly. The top layer of each MLI assembly is fluorinated ethylene propylene (FEP, a type of Teflon). Dramatic changes in material properties were observed when comparing areas of high solar fluence to areas of low solar fluence. Cross sectional analysis shows atomic oxygen (AO) erosion values up to 25.4 mu m (1 mil). Greater occurrences of through-thickness cracking and surface microcracking were observed in areas of high solar exposure. Atomic force microscopy (AFM) showed increases in surface microhardness measurements with increasing solar exposure. Decreases in FEP tensile strength and elongation were measured when compared to non-flight material. Erosion yield and tensile results are compared with FEP data from the Long Duration Exposure Facility. AO erosion yield data, solar fluence values, contamination, micrometeoroid or debris impact sites, and optical properties are presented.

  7. Environmental Degradation of Materials: Surface Chemistry Related to Stress Corrosion Cracking

    Science.gov (United States)

    Schwarz, J. A.

    1985-01-01

    Parallel experiments have been performed in order to develop a comprehensive model for stress cracking (SCC) in structural materials. The central objective is to determine the relationship between the activity and selectivity of the microstructure of structural materials to their dissolution kinetics and experimentally measured SCC kinetics. Zinc was chosen as a prototype metal system. The SCC behavior of two oriented single-crystal disks of zinc in a chromic oxide/sodium sulfate solution (Palmerton solution) were determined. It was found that: (1) the dissolution rate is strongly (hkil)-dependent and proportional to the exposure time in the aggressive environment; and (2) a specific slip system is selectively active to dissolution under applied stress and this slip line controls crack initiation and propagation. As a precursor to potential microgrvity experiments, electrophoretic mobility measurements of zinc particles were obtained in solutions of sodium sulfate (0.0033 M) with concentrations of dissolved oxygen from 2 to 8 ppm. The equilibrium distribution of exposed oriented planes as well as their correlation will determine the particle mobility.

  8. Stepwise transformation of the molecular building blocks in a porphyrin-encapsulating metal-organic material

    KAUST Repository

    Zhang, ZhenJie

    2013-04-24

    When immersed in solutions containing Cu(II) cations, the microporous metal-organic material P11 ([Cd4(BPT)4]·[Cd(C 44H36N8)(S)]·[S], BPT = biphenyl-3,4′,5-tricarboxylate) undergoes a transformation of its [Cd 2(COO)6]2- molecular building blocks (MBBs) into novel tetranuclear [Cu4X2(COO)6(S) 2] MBBs to form P11-Cu. The transformation occurs in single-crystal to single-crystal fashion, and its stepwise mechanism was studied by varying the Cd2+/Cu2+ ratio of the solution in which crystals of P11 were immersed. P11-16/1 (Cd in framework retained, Cd in encapsulated porphyrins exchanged) and other intermediate phases were thereby isolated and structurally characterized. P11-16/1 and P11-Cu retain the microporosity of P11, and the relatively larger MBBs in P11-Cu permit a 20% unit cell expansion and afford a higher surface area and a larger pore size. © 2013 American Chemical Society.

  9. Effect of ventilation on perceived quality of air polluted by building materials. A summary of reported data

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-02-15

    This paper summarizes existing data on how varying ventilation rates affect the perceived quality of air polluted by building materials. This is done by reviewing literature dealing with exposure-response relationships, i.e. the log-linear relationships between the concentration of pollutants (exposure) and the perceived air quality (response). The reviewed data originate from studies with single building materials performed in small-scale ventilated chambers and from studies carried out in a full-scale setting resembling normal offices. Perceived air quality expressed in terms of acceptability as assessed by untrained panels was included. The results show that the exposure-response relationships vary for different building materials as regards the impact of changing ventilation rate on perceived air quality and the level of perceived air quality at a constant ventilation rate. This applies both for the data collected in small-scale and in full-scale experiments. The differences may be caused by the experimental conditions, psychological factors, physiological factors, and chemical/physical factors. A well controlled study taking these factors into account with several different building materials, is thus recommended to further study whether the observed results have practical significance. These experiments should be carried out under realistic fullscale conditions. (au)

  10. Study of the influence of porosity on the radon emanation coefficient in different building material samples by combining the SSNTD technique with Monte Carlo simulations

    CERN Document Server

    Misdaq, M A; Ktata, A

    1998-01-01

    Radon alpha-activities per unit volume have been measured inside and outside different building material samples by using CR-39 and LR-115 type II solid state nuclear track detectors (SSNTD). Radon emanation coefficients of the studied building materials have been evaluated. The porosities of the building material samples studied have been determined by using a Monte Carlo calculational method adapted to the experimental conditions and compared with data obtained by the Archimedes's method. The influence of the building material porosity on the radon emanation coefficient has been investigated.

  11. Production of fiberglass/metal composite material suitable for building habitat and manufacturing facilities

    Science.gov (United States)

    1987-01-01

    The production of a fiberglass/metal composite material suitable for building habitats and manufacturing facilities was the project for Clemson. The concept and development of the knowledge necessary to produce glass fibers originated in the spring semester. During the summer, while at Johnson Space Center, fiberglass from a rock composition similar to ones found at the Apollo 16 site on the moon was successfully produced. The project this year was a continuation of last year's studies. We addressed the following problems which emerged as the work progressed: (1) Methods for coating the fibers with a metal were explored. We manufactured composites in two stages: Glass fibers without any coating on them; and fibers coated with metals as they were made. This proved to be a difficult process. Future activities include using a chemical vapor deposition process on fibers which have been made. (2) A glass furnace was developed which relies primarily on solar energy for melting the glass. The temperature of the melted glass is maintained by electrical means. The design is for 250 kg of glass per day. An electrical engineering student developed a scheme for controlling the melting and manufacturing process from the earth. This was done to minimize the human risk. Graphite refractories are relied on to contain the melt. (3) The glass composition chosen for the project is a relatively pure anorthite which is available in the highland regions of the lunar surface. A major problems with this material is that it melts at a comparatively high temperature. This problem will be solved by using graphite refractory materials for the furnace. The advantage of this glass composition is that it is very stable and does not tend to crystallize. (4) We have also refined the experimental furnace and fiber making machinery which we will be using at Johnson Space Center this summer. We believe that we will be able to draw and coat glass fibers in a vacuum for use in composites. We intend to

  12. Degraded areas of organised multi-apartment building between 1945 and 1965 in Slovenia – methodology of evaluation and rehabilitation

    Directory of Open Access Journals (Sweden)

    Tadeja Zupančič Strojan

    2002-01-01

    Full Text Available “Degraded” housing areas represent a 9% share of urbanised surfaces of thirty-five in planning terms recently researched Slovenian towns. Above all social housing estates built between 1945 and 1965 present issues since they are isolated, poorly maintained, and cannot reach modern standards. The research contemplates the redirecting of the present abstract planning rationales to the real architectural, user level. Further intentions of the research are to consolidate ideas about the urgency of renewal as the only possible method of solving problems of a certain pattern of building, to determine criteria and measures for renewal and to determine rational or real directions for concrete contributions for the improvement of the standard of living, in short, to a new shift in living culture discussed settlement pattern.

  13. Disintegration of sedimentary rocks used as building material: evaluation and quantification in 4D

    Science.gov (United States)

    Dewanckele, J.; Boone, M. A.; de Kock, T.; Cnudde, V.; Boone, M. N.; de Witte, Y.; Pieters, K.; van Loo, D.; van Hoorebeke, L.; Jacobs, P.

    2009-04-01

    clearly be visualized. This is an important aspect since most weathering processes take place in the presence of water. To evaluate rocks used as building material, several standard durability tests (freeze-thaw cycle, thermal shock…) exist. The significance of these tests lies in the predictability of the stone's weathering behaviour or resistance under known external conditions. After the tests, the stone's new physical properties are evaluated with regard to its initial condition. Most of the time, these evaluations are based on visual inspection and qualitative interpretation. With the aid of X-ray computed tomography it is possible to quantify the deterioration of the stone in high resolution, before and after the durability tests. For that purpose several subsamples consisting of cylindrical cores with a diameter around 8 mm and standardized cubic samples with a length of 5 cm were scanned with high resolution. Quantification of the internal structure was calculated using the software package Morpho+. The scans were carried out at the "Centre for X-ray Tomography" at Ghent University (UGCT), Belgium. Micro-cracks, changes in pore structure and element migration were quantified with micrometer resolution. Orientation and length of cracks can be measured in function of time. Based on these results, a clear difference in response to weathering can be observed over time with micrometer resolution.

  14. Sense and shoot: simultaneous detection and degradation of low-level contaminants using graphene-based smart material assembly.

    Science.gov (United States)

    Alam, Rabeka; Lightcap, Ian V; Karwacki, Christopher J; Kamat, Prashant V

    2014-07-22

    Smart material nanoassemblies that can simultaneously sense and shoot low-level contaminants from air and water are important for overcoming the threat of hazardous chemicals. Graphene oxide (GO) sheets deposited on mesoscopic TiO2 films that underpin the deposition of Ag nanoparticles with UV irradiation provide the foundation for the design of a smart material. The Ag particle size is readily controlled through precursor concentration and UV irradiation time. These semiconductor–graphene oxide–metal (SGM) films are SERS-active and hence capable of sensing aromatic contaminants such as 4-nitrobenzenethiol (4-NBT) in nanomolar range. Increased local concentration of organic molecules achieved through interaction with 2-D carbon support (GO) facilitates low-level detection of contaminants. Upon UV irradiation of 4-NBT-loaded SGM film, one can induce photocatalytic transformations. Thus, each component of the SGM film plays a pivotal role in aiding the detection and degradation of a contaminant dispersed in aqueous solutions. The advantage of using SGM films as multipurpose “detect and destroy” systems for nitroaromatic molecules is discussed.

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

    Directory of Open Access Journals (Sweden)

    Blain, Sophie

    2010-12-01

    Full Text Available The research reported in this thesis concerns the re-evaluation of an archaeological assumption surrounding the origin of Ceramic Building Materials (CBM used from the 9th to the 11th century in religious buildings of north-western France and south-eastern England. Are the bricks used in the masonry structures Roman spolia or a novo productions? Amongst the dating methods that can contribute to building archaeology, it is the technique of stimulated luminescence applied to CBM that is the focus of this study. Results from thermoluminescence (TL and optically stimulated luminescence (OSL dating performed on 52 CBM samples from 11 churches showed that the practice of reusing Roman brick was commonplace in small parish churches, but also that brick-making was not a totally unknown skill of the early medieval craftsmen as it has long been supposed. Most importantly, by identifying that the building material is contemporary to the church, a defined chronology emerges resulting in a new and extremely useful reference point in the history of early medieval architecture.La investigación presentada en esta tesis se ocupa de la reevaluación de un supuesto arqueológico entorno al origen del material cerámico constructivo (CBM empleado entre los siglos IX y XI en los edificios religiosos del Noroeste de Francia y el Sudeste de Inglaterra. ¿Son los ladrillos empleados en las estructuras de fábrica spolia romana o producciones a novo? Entre los métodos de datación que pueden contribuir a la arqueología del edificio, la técnica de luminiscencia estimulada aplicada al CBM es el centro de este estudio. Los resultados de la termoluminiscencia (TL y de la luminiscencia estimulada ópticamente (OSL, aplicadas en 52 muestras de CBM tomadas en 11 iglesias, evidencian que la práctica de reutilizar ladrillos romanos era común en pequeñas iglesias parroquiales, pero que también la técnica de elaboración de ladrillos no era totalmente desconocida para los

  16. Optimization model for the selection of materials using a LEED-based green building rating system in Colombia

    Energy Technology Data Exchange (ETDEWEB)

    Castro-Lacouture, Daniel [Building Construction Program, College of Architecture, Georgia Institute of Technology, 280 Ferst Drive, Atlanta, GA 30332 (United States); Sefair, Jorge A.; Florez, Laura; Medaglia, Andres L. [Centro de Optimizacion y Probabilidad Aplicada (COPA), Departamento de Ingenieria Industrial, Universidad de los Andes, Bogota D.C. (Colombia)

    2009-06-15

    Buildings have a significant and continuously increasing impact on the environment because they are responsible for a large portion of carbon emissions and use a considerable number of resources and energy. The green building movement emerged to mitigate these effects and to improve the building construction process. This paradigm shift should bring significant environmental, economic, financial, and social benefits. However, to realize such benefits, efforts are required not only in the selection of appropriate technologies but also in the choice of proper materials. Selecting inappropriate materials can be expensive, but more importantly, it may preclude the achievement of the desired environmental goals. In order to help decision-makers with the selection of the right materials, this study proposes a mixed integer optimization model that incorporates design and budget constraints while maximizing the number of credits reached under the Leadership in Energy and Environmental Design (LEED) rating system. To illustrate this model, this paper presents a case study of a building in Colombia in which a modified version of LEED is proposed. (author)

  17. Recognition of materials and damage on historical buildings using digital image classification

    Directory of Open Access Journals (Sweden)

    Jose E. Merono

    2015-01-01

    Full Text Available Nowadays, techniques in digital image processing make it possible to detect damage, such as moisture or biological changes, on the surfaces of historical buildings. Digital classification techniques can be used to identify damages in construction materials in a non-destructive way. In this study, we evaluate the application of the object-oriented classification technique using photographs taken with a Fujifilm IS-Pro digital single lens reflex camera and the integration of the classified images in a three-dimensional model obtained through terrestrial laser scanning data in order to detect and locate damage affecting biocalcarenite stone employed in the construction of the Santa Marina Church (Córdoba, Spain. The Fujifilm IS-Pro camera captures spectral information in an extra-visible range, generating a wide spectral image with wavelengths ranging from ultraviolet to infrared. Techniques of object-oriented classification were applied, taking into account the shapes, textures, background information and spectral information in the image. This type of classification requires prior segmentation, defined as the search for homogeneous regions in an image. The second step is the classification process of these regions based on examples. The output data were classified according to the kind of damage that affects the biocalcarenite stone, reaching an overall classification accuracy of 92% and an excellent kappa statistic (85.7%. We have shown that multispectral classification with visible and near-infrared bands increased the degree of recognition among different damages. Post-analysis of these data integrated in a three-dimensional model allows us to obtain thematic maps with the size and position of the damage.

  18. Novel Mold-Resistant Building Materials Impregnated with Thermally Reduced Nano-Silver.

    Science.gov (United States)

    Chen, Yen-Chi; Yu, Kuo-Pin; Shao, Wen-Cheng; Tseng, Chao-Heng; Pan, Wen-Chi

    2017-12-11

    In this study, we evaluated the long-term antifungal effectiveness of 3 types of interior building materials (gypsum board (GB), cement board (CB) and softwood plywood (S-PW)) impregnated with thermally reduced silver nanoparticles supported by titanium dioxide (AgNPs/TiO2 ) under 95% relative humidity for four weeks. AgNPs/TiO2 was synthesized at two thermal reduction temperatures (TRTs, 120 and 200°C) with two different AgNP weight percentages (2 and 5 wt%). Four different silver loading levels (SLLs, 0.025, 0.05, and 0.5 μg/cm2 and the critical concentration required to inhibit fungal growth on agar plates) and three fungal species (A. niger, P. spinulosum and S. chartarum) were used in the experiments. Higher temperature reduced more ionic Ag+ to metallic Ag0 and increased the dispersion of Ag on TiO2 surface. The 200°C thermally reduced AgNPs/TiO2 demonstrated excellent antifungal efficiency: mold growth was almost completely inhibited for 28 days at the low SLL of 0.5 μg/cm2 . Additionally, AgNPs/TiO2 exhibited higher antifungal activity on GB and CB than on S-PW. The stepwise regression results indicated that the TRT of AgNPs/TiO2 (β =-0.739--0.51), the SLL (β =-0.477--0.269), and the Ag0 level in the AgNPs (β=-0.379--0.136) were the major factors influencing antifungal activity and TRT might be the most significant one. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  19. Impact of conservation agriculture on harnessing sustainability and building resilience against land degradation in the northern Ethiopian highlands

    Science.gov (United States)

    Araya, Tesfay; Cornelis, Wim M.; Govaerts, Bram; Bauer, Hans; Deckers, Jozef; Nyssen, Jan

    2013-04-01

    Conservation Agriculture (CA) aims at improving soil quality and crop yield whilst reducing runoff and topsoil erosion which raises the soil resilience to combat soil degradation. Different chemical, physical, and biological properties of a soil interact in complex ways that determine the crop productivity potential of the soil. Hence, a medium-term tillage experiment was carried out (2005 to 2011) on a Vertisol to evaluate changes in soil quality, runoff and soil loss due to CA-based field conservation practices in northern Ethiopia. The experimental layout was implemented in a randomized complete block design with three replications on permanent plots of 5 m by 19 m. The tillage treatments were derdero+ (DER+) with a furrow and permanent raised bed planting system, plowed once at planting by refreshing the furrow and with 30% standing crop residue retention, terwah+ (TER+) with plowing once at planting with 30% standing crop residue retention and contour furrows made at 1.5 m distance interval, and conventional tillage (CT) with a minimum of three tillage operations and removal of crop residues. All the plowing and reshaping of the furrows was done using the local ard plow mahresha. Local crop rotation practices followed during the seven years sequentially from the first to the seventh year included wheat-teff-wheat-barley-wheat-teff-grass pea. Glyphosate was sprayed starting from the third year (2007) at 2 l ha-1 before planting to control pre-emergent weed in DER+ and TER+. Significantly different (pagriculture principles can reduce runoff, soil loss and improve crop yield and soil quality and thus, sustainability in Vertisols. Keywords: Soil resilience, Vertisol, conservation agriculture, field conservation practices, soil quality

  20. Mathematical modeling of the emission of heavy metals into water bodies from building materials derived from production waste

    Directory of Open Access Journals (Sweden)

    Pugin Konstantin Georgievich

    2016-01-01

    Full Text Available At the present time industrial waste is considered to be an alternative to primary natural resources when producing construction materials and products. The use of industrial waste in the construction branch allows reducing ecological load on the environment and population as a result of reducing the amount of unrecyclable waste and reducing the use of primary natural resources. Though when involving waste products as raw material in the preparation of building materials there occur environmental risks of anthropogenic impact increase on the environment. These risks are related to possible emission of heavy metals from construction materials in use. The article describes a tool which allows predicting this issue, depending on the acidity of the medium, the residence time of the material in the environment. The experimental data obtained in determining the migration activity of metals from cement concretes to aqueous solutions served as the basis for the mathematical model. The proposed model allows us to make a prediction of anthropogenic impact on the environment and commensurate this impact with the possibility of assimilation of the environment area where the building materials are applied. This will allow conducting an effective assessment of the created and applied technologies of waste disposal, taking into account the operating conditions of the materials produced.