WorldWideScience

Sample records for fire retardant chemistry

  1. Fire and smoke retardants

    Science.gov (United States)

    Drews, M. J.

    Despite a reduction in Federal regulatory activity, research concerned with flame retardancy and smoke suppression in the private sector appears to be increasing. This trend seem related to the increased utilization of plastics for end uses which traditionally have employed metal or wood products. As a result, new markets have appeared for thermally stable and fire resistance thermoplastic materials, and this in turn has spurred research and development activity. In addition, public awareness of the dangers associated with fire has increased as a result of several highly publicized hotel and restaurant fires within the past two years. The consumers recognition of flammability characteristics as important materials property considerations has increased. The current status of fire and smoke retardant chemistry and research are summarized.

  2. Fire retardant formulations

    DEFF Research Database (Denmark)

    2017-01-01

    The present invention relates to compositions where a substrate is liable to catch fire such as bituminous products, paints, carpets or the like. The invention relates to a composition comprising 40-95 weight % of a substrate to be rendered fire resistant such as bituminous material or paint......, carpets which substrate is mixed with 5-60 weight % of a fire retardant component. The invention relates to a fire retardant component comprising or being constituted of attapulgite, and a salt being a source of a blowing or expanding agent, where the attapulgite and the salt are electrostatically...... connected by mixing and subjecting the mixture of the two components to agitation. Also, the invention relates to compositions comprising 40-95 weight % of a substrate to be rendered fire resistant mixed with 5-60 weight % of a fire retardant according to claim 1 or 2, which fire retardant component...

  3. Fire retardant polyisocyanurate foam

    Science.gov (United States)

    Riccitiello, S. R.; Parker, J. A.

    1972-01-01

    Fire retardant properties of low density polymer foam are increased. Foam has pendant nitrile groups which form thermally-stable heterocyclic structures at temperature below degradation temperature of urethane linkages.

  4. Fire-retardant foams

    Science.gov (United States)

    Gagliani, J.

    1978-01-01

    Family of polyimide resins are being developed as foams with exceptional fire-retardant properties. Foams are potentially useful for seat cushions in aircraft and ground vehicles and for applications such as home furnishings and building-construction materials. Basic formulations can be modified with reinforcing fibers or fillers to produce celular materials for variety of applications. By selecting reactants, polymer structure can be modified to give foams with properties ranging from high resiliency and flexibility to brittleness and rigidity.

  5. Can earthworms survive fire retardants?

    Science.gov (United States)

    Beyer, W.N.; Olson, A.

    1996-01-01

    Most common fire retardants are foams or are similar to common agricultural fertilizers, such as ammonium sulfate and ammonium phosphate. Although fire retardants are widely applied to soils, we lack basic information about their toxicities to soil organisms. We measured the toxicity of five fire retardants (Firetrol LCG-R, Firetrol GTS-R, Silv-Ex Foam Concentrate, Phos-chek D-75, and Phos-chek WD-881) to earthworms using the pesticide toxicity test developed for earthworms by the European Economic Community. None was lethal at 1,000 ppm in the soil, which was suggested as a relatively high exposure under normal applications. We concluded that the fire retardants tested are relatively nontoxic to soil organisms compared with other environmental chemicals and that they probably do not reduce earthworm populations when applied under usual firefighting conditions.

  6. Intumescent Coatings as Fire Retardants

    Science.gov (United States)

    Parker, J. A.; Fohlen, G. M.; Sawko, P. M.; Fish, R. H.

    1970-01-01

    The development of fire-retardant coatings to protect surfaces which may be exposed to fire or extreme heat is a subject of intense interest to many industries. A fire-retardant paint has been developed which represents a new chemical approach for preparing intumescent coatings, and potentially, is very important to fire-prevention authorities. The requirements for a superior coating include ease of application, suitability to a wide variety of surfaces and finishes, and stability over an extended period of time within a broad range of ambient temperature and humidity conditions. These innovative coatings, when activated by the heat of a fire, react to form a thick, low-density, polymeric coating or char layer. Water vapor and sulphur dioxide are released during the intumescent reaction. Two fire-protection mechanisms thus become available: (1) the char layer retards the flow of heat, due to the extremely low thermal conductivity; and (2) water vapor and sulfur dioxide are released, providing fire quenching properties. Still another mechanism functions in cases where the char, by virtue of its high oxidation resistance and low thermal conductivity, reaches a sufficiently high temperature to re-radiate much of the incident heat load. The coatings consist of dispersions of selective salts of a nitro-amino-arornatic compound. Specifically, para-nitroaniline bisulfate and the ammonium salt of para-nitroaniline-ortho sulphuric acid (2-amino-5-nitrobenzenesulphuric acid) are used. Suitable vehicles are cellulose nitrate of lacquer grade, a nitrite-phenolic modified rubber, or epoxy-polysulfide copolymer. Three separate formulations have been developed. A solvent is usually employed, such as methylethyl ketone, butyl acetate, or toluene, which renders the coatings suitably thin and which evaporates after the coatings are applied. Generally, the intumescent material is treated as insoluble in the vehicle, and is ground and dispersed in the vehicle and solvent like an

  7. Fire-retardant-treated strandboard : properties and fire performance

    Science.gov (United States)

    Jerrold Winandy; Qingwen Wang; Robert H. White

    2008-01-01

    This study evaluated a series of single-layer, randomly oriented strandboard panels made with one resin type, a single resin loading level, and four fire-retardant-treatment levels. The fire retardant (FR) evaluated was a pH-buffered combination of boric acid and organic phosphate. Siberian larch strands were separated into five batches. One batch of strands served as...

  8. Fire-retardant decorative inks for aircraft interiors

    Science.gov (United States)

    Kourtides, D. A.; Nir, Z.; Mikroyannidis, J. A.

    1985-01-01

    Commercial and experimental fire retardants were screened as potential fire retardants for acrylic printing inks used on aircraft interior sandwich panels. The fire retardants are selected according to their physical properties and their thermostabilities. A criterion for selecting a more stable fire retardant is established. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) are used to determine thermostabilities. Results show that the fire retardant formulations are more thermally stable than the acrylic ink control. It is determined that an ink formulation containing a brominated phenol and carboxy-terminated butadiene acrylonitrile which has been modified with a brominated polymeric additive (BPA), yields the highest limiting oxygen index (LOI) of all the compounds tested. All of the fire-retardant formulations have a higher oxygen index than the baseline acrylic ink.

  9. Fire retardation of polystyrene/clay nanocomposites: initial study on synergy effect

    Czech Academy of Sciences Publication Activity Database

    Dujková, Z.; Měřínská, D.; Šlouf, Miroslav

    2013-01-01

    Roč. 26, č. 9 (2013), s. 1278-1286 ISSN 0892-7057 Institutional research plan: CEZ:AV0Z40500505 Keywords : fire retardation * synergy * clay Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.134, year: 2013

  10. Colemanite: a fire retardant candidate for wood plastic composites

    Science.gov (United States)

    Evren Terzi; Saip Nami Kartal; Sabriye Piskin; Nicole Stark; Aysel Kanturk Figen; Robert H. White

    2018-01-01

    The use of raw boron minerals (i.e. tincalconite, colemanite, and ulexite) was evaluated to increase the fire performance of wood plastic composites (WPCs) in comparison with commercially available fire retardants (FRs). Cone calorimetry and limited oxygen index tests were performed to evaluate the fire properties of WPC specimens. Artificial weathering and 3-point...

  11. Accelerated weathering of fire-retardant-treated wood for fire testing

    Science.gov (United States)

    Robert H. White

    2009-01-01

    Fire-retardant-treated products for exterior applications must be subjected to actual or accelerated weathering prior to fire testing. For fire-retardant-treated wood, the two accelerated weathering methods have been Method A and B of ASTM D 2898. The rain test is Method A of ASTM D 2898. Method B includes exposures to ultraviolet (UV) sunlamps in addition to water...

  12. Effects of fire retardants on physical, mechanical, and fire properties of flat-pressed WPCs

    Science.gov (United States)

    Nadir Ayrilmis; Jan T. Benthien; Heiko Thoemen; Robert H. White

    2012-01-01

    Physical, mechanical, and fire properties of the flat-pressed wood plastic composites (WPCs) incorporated with various fire retardants (10% by weight) at different levels of wood flour (WF) content, 40, 50, or 60 wt%, were investigated. The WPC panels were made from dry-blended WF, polypropylene (PP), and fire retardant (FR) powders with maleic anhydride-grafted PP (2...

  13. Chemistry fighting against fires

    International Nuclear Information System (INIS)

    Raffalsky, K.

    1975-01-01

    A detailed report is given on the general principle 'fire' and on fires as fast chemical reactions between consumable material and oxygen of the air (exothermal oxidation) as well as on the classes of fires A to D. Class D includes strongly incadescent burnable metals such as K, Na, Li, Cs, Rb, U, Pu, Ce, Zr, Be, Ca, Sr, Ba etc. The burning process, the extinguishing effects, the development of the extinguisher and its present state are individually dealt with. (HK/LH) [de

  14. Development of highly fire-retardant irradiated polyolefin cables

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, Keiji; Inui, Toshifumi; Uda, Ikujiro (Sumitomo Electric Industries Ltd., Osaka (Japan))

    1982-12-01

    In recent years, motors, automobiles, heaters, etc., have been made into light weight and compact form in view of labour-saving and energy-saving. For this purpose, the wires for the electrical appliances used for these equipment are required to reduce insulation thickness and to improve heat resistance. On the other hand, the requirement for fire-retardant property has become severer than before from the viewpoint of safety. As an insulation for the wires which meets such requirement, the polyolefin cross-linked by irradiation was investigated, and the heat-resistant, highly fire-retardant, polyolefin-insulated wires have been developed, which have passed vertical combustion test (VW-1) and have the insulation thickness of 0.4 mm (voltage rating 300V) and UL standard 125 deg C and 150 deg C grades. Fire-retardant polyolefin resin is normally obtained by adding halogen series flame retarders. The selection of flame retarders requires the investigation on high thermal stability, high flame retardation, no impedance to cross-linking, and good dispersion into polymers. The evaluation of heat resistance performed on two points, thermal aging and thermal deformation. The use of oxidation inhibitors is indispensable to improve the anti-thermal aging capability, but it is important to balance the requirements well by combining oxidation inhibitors, considering thermal deformation, colouring and discolouration. By comparative test with silicone rubber, cross-linked polyethylene and cross-linked PVC-insulated wires, the characteristics of highly fire-retardant wires, insulated with polyethylene cross-linked by irradiation, are described about the fire retardation, thermal deformation, thermal aging resistance, electrical characteristics and oil resistance.

  15. Physical, mechanical, and fire properties of oriented strandboard with fire retardant treated veneers

    Science.gov (United States)

    Nadir Ayrilmis; Zeki Candan; Robert White

    2007-01-01

    This study evaluated physical, mechanical and fire properties of oriented strand boards (OSB) covered with fire retardant treated veneers. The beech (Fagus orientalis Lipsky) veneers were treated with either monoammonium phosphate, diammonium phosphate, lime water or a borax/boric acid (1 : 1 by weight) mixture. Physical and mechanical properties of the specimens were...

  16. Thermal characterization of intumescent fire retardant paints

    International Nuclear Information System (INIS)

    Calabrese, L; Bozzoli, F; Rainieri, S; Pagliarini, G; Bochicchio, G; Tessadri, B

    2014-01-01

    Intumescent coatings are now the dominant passive fire protection materials used in industrial and commercial buildings. The coatings, which usually are composed of inorganic components contained in a polymer matrix, are inert at low temperatures and at higher temperatures, they expand and degrade to provide a charred layer of low conductivity materials. The charred layer, which acts as thermal barrier, will prevent heat transfer to underlying substrate. The thermal properties of intumescent paints are often unknown and difficult to be estimated since they vary significantly during the expansion process; for this reason the fire resistance validation of a commercial coatings is based on expensive, large-scale methods where each commercial coating-beam configuration has to be tested one by one. Adopting, instead, approaches based on a thermal modelling of the intumescent paint coating could provide an helpful tool to make easier the test procedure and to support the design of fire resistant structures as well. The present investigation is focused on the assessment of a methodology intended to the restoration of the equivalent thermal conductivity of the intumescent layer produced under the action of a cone calorimetric apparatus. The estimation procedure is based on the inverse heat conduction problem approach, where the temperature values measured at some locations inside the layer during the expansion process are used as input known data. The results point out that the equivalent thermal conductivity reached by the intumescent material at the end of the expansion process significantly depends on the temperature while the initial thickness of the paint does not seem to have much effect

  17. Thermal characterization of intumescent fire retardant paints

    Science.gov (United States)

    Calabrese, L.; Bozzoli, F.; Bochicchio, G.; Tessadri, B.; Rainieri, S.; Pagliarini, G.

    2014-11-01

    Intumescent coatings are now the dominant passive fire protection materials used in industrial and commercial buildings. The coatings, which usually are composed of inorganic components contained in a polymer matrix, are inert at low temperatures and at higher temperatures, they expand and degrade to provide a charred layer of low conductivity materials. The charred layer, which acts as thermal barrier, will prevent heat transfer to underlying substrate. The thermal properties of intumescent paints are often unknown and difficult to be estimated since they vary significantly during the expansion process; for this reason the fire resistance validation of a commercial coatings is based on expensive, large-scale methods where each commercial coating-beam configuration has to be tested one by one. Adopting, instead, approaches based on a thermal modelling of the intumescent paint coating could provide an helpful tool to make easier the test procedure and to support the design of fire resistant structures as well. The present investigation is focused on the assessment of a methodology intended to the restoration of the equivalent thermal conductivity of the intumescent layer produced under the action of a cone calorimetric apparatus. The estimation procedure is based on the inverse heat conduction problem approach, where the temperature values measured at some locations inside the layer during the expansion process are used as input known data. The results point out that the equivalent thermal conductivity reached by the intumescent material at the end of the expansion process significantly depends on the temperature while the initial thickness of the paint does not seem to have much effect.

  18. 75 FR 52713 - Nationwide Aerial Application of Fire Retardant on National Forest System Lands

    Science.gov (United States)

    2010-08-27

    ... DEPARTMENT OF AGRICULTURE Forest Service Nationwide Aerial Application of Fire Retardant on... statement for the continued nationwide aerial application of fire retardant on National Forest System lands... Forest Service is working to restore fire-adapted ecosystems through prescribed fire, other fuel...

  19. Improved fire retardancy of thermoset composites modified with carbon nanofibers

    International Nuclear Information System (INIS)

    Zhao Zhongfu; Gou Jan

    2009-01-01

    Multifunctional thermoset composites were made from polyester resin, glass fiber mats and carbon nanofiber sheets (CNS). Their flaming behavior was investigated with cone calorimeter under well-controlled combustion conditions. The heat release rate was lowered by pre-planting carbon nanofiber sheets on the sample surface with the total fiber content of only 0.38 wt.%. Electron microscopy showed that carbon nanofiber sheet was partly burned and charred materials were formed on the combusting surface. Both the nanofibers and charred materials acted as an excellent insulator and/or mass transport barrier, improving the fire retardancy of the composite. This behavior agrees well with the general mechanism of fire retardancy in various nanoparticle-thermoplastic composites.

  20. Development of new radiation resistant, fire-retardant cables

    International Nuclear Information System (INIS)

    Hagiwara, Ko; Morita, Yosuke; Udagawa, Takashi; Fujimura, Shun-ichi; Oda, Eisuke.

    1982-01-01

    For the cables for nuclear facilities, radiation resistance and fire-retardation are severely required. The authors took note of the fact that even in the existing cables for nuclear power plants, their mechanical properties are greatly degraded by the exposure to large dose (for example, 200 Mrad in PWR testing conditions), and attempted the improvement. They employed a new additive, bromated acenaphthylene condensate (con-BACN), which effectively gives radiation resistance and also is a good flame retarder, to be compounded to an insulation material, and examined the characteristics. In this paper, the features of con-BACN and the investigation of fire-retardant EPDM composition are described. As an initial composition, a small amount of zinc white, sulphur, stearic acid, noclac 224 (Ouchi-Shinko Chemicals, Co.), and antimony trioxide, 100 parts of tale and 45 parts of con-BACN were added to 100 parts of EPDM (propylene content 34 %, Japan Synthetic Rubber Co.). As the antiaging agent, it was decided to use phenol series No. 3 as a result of test. The fire-retardant EP rubber-composed cable was produced for trial, its insulation being fabricated, using a Furukawa's pressurized salt bath continuous vulcanizer. The tests of γ-irradiation, simulated LOCA and combustion were carried out, and the test results are reported. It was indicated that the cable resisted against high dose several times as much as 200 Mrad, and was suitable for the applications, in which the mechanical properties such as bending are required to be maintained after radiation exposure. It was also found that con-BACN was safe, and its properties of decomposition, concentration and acute toxicity were all very low. (Wakatsuki, Y.)

  1. Lightweight, fire-retardant, crashworthy aircraft seat cushioning

    Science.gov (United States)

    Haslim, Leonard A.; Mcdonough, Paul T.

    1991-01-01

    A two page discussion of non-aerospace seating applications and the design of NASA's safety seat cushioning (SSC) is presented. The SSC was designed for both safety and comfort in order to replace polyurethane cushioning which is flammable and produces lethal fumes upon combustion. The SSC is composed of advanced fabric reinforced composites and is lightweight, fire-retardent, and crashworthy. The seat design consists of central elliptical tubular spring supports made of fire-resistant and fatigue-durable composites surrounded by a fire-blocking sheath. The cushioning is made crashworthy by incorporating energy-absorbing, viscoelastic layers between the nested, elliptical-hoop springs. The design is intended to provide comfortable seating that meets aircraft-loading requirements without using the conventional polyurethane materials. The designs of an aircraft seat and structural components of the SSC are also presented.

  2. THE REACTION TO FIRE TEST FOR FIRE RETARDANT AND FOR COMBUSTIBLE MATERIAL

    Directory of Open Access Journals (Sweden)

    Adelaida FANFAROVÁ

    2016-12-01

    Full Text Available Currently the natural materials become popular building material for houses, buildings and recreational property. The risk of fires in residential timber construction or eco houses cannot be completely ruled out, therefore there is a need for proper and correct implementing preventive measures and application of all available solutions, which may reduce the risk of fire as far as possible, to slow down the combustion process, to protect the life of people, animals and also the building itself until arrival members of the Fire and Rescue Services. Fireproofing of combustible materials is a specific area of fire protection. For scientific research as well as for real-life practice, not only their structural and physical properties, but also fire-technical characteristics are really important. The present researchers mostly focus on fire-retardant treatment of wood that is why the authors of this contribution focused on a different combustible material. This research article presents the experimental testing and examination of the reaction to fire test of the selected thermal insulation of hemp fiber that was impregnated by the selected fire retardant in laboratory conditions.

  3. Fire-Retardant, Self-Extinguishing Inorganic/Polymer Composite Memory Foams.

    Science.gov (United States)

    Chatterjee, Soumyajyoti; Shanmuganathan, Kadhiravan; Kumaraswamy, Guruswamy

    2017-12-27

    Polymeric foams used in furniture and automotive and aircraft seating applications rely on the incorporation of environmentally hazardous fire-retardant additives to meet fire safety norms. This has occasioned significant interest in novel approaches to the elimination of fire-retardant additives. Foams based on polymer nanocomposites or based on fire-retardant coatings show compromised mechanical performance and require additional processing steps. Here, we demonstrate a one-step preparation of a fire-retardant ice-templated inorganic/polymer hybrid that does not incorporate fire-retardant additives. The hybrid foams exhibit excellent mechanical properties. They are elastic to large compressional strain, despite the high inorganic content. They also exhibit tunable mechanical recovery, including viscoelastic "memory". These hybrid foams are prepared using ice-templating that relies on a green solvent, water, as a porogen. Because these foams are predominantly comprised of inorganic components, they exhibit exceptional fire retardance in torch burn tests and are self-extinguishing. After being subjected to a flame, the foam retains its porous structure and does not drip or collapse. In micro-combustion calorimetry, the hybrid foams show a peak heat release rate that is only 25% that of a commercial fire-retardant polyurethanes. Finally, we demonstrate that we can use ice-templating to prepare hybrid foams with different inorganic colloids, including cheap commercial materials. We also demonstrate that ice-templating is amenable to scale up, without loss of mechanical performance or fire-retardant properties.

  4. Weathering methods for preservative treated wood and their applicability for fire retarded wood

    NARCIS (Netherlands)

    Voss, A.

    1999-01-01

    preservative treated wood. The aim of the presentation is to inform you about current testing methods and to discuss their applicability to test fire retarded wood in outdoor use. Assuming that fire retardants will only be used in out of ground contact, only those methods are mentioned, which fit

  5. Toxicity of fire retardant chemicals and fire suppressant foams to vertebrate and invertebrate wildlife species

    Science.gov (United States)

    Vyas, Nimish B.; Hill, Elwood F.

    1996-01-01

    Under laboratory conditions, acute single-dose oral toxicity tests (LD50) were conducted with three fire retardant chemicals (Fire-Trol GTS-R, Phos-Chek D75-F, and Fire-Trol LCG-R) and two fire suppressant foams (Silv-Ex and Phos-Chek WD-881) to determine effects on adult northern bobwhite, American kestrel, red-winged blackbird, and white-footed mouse. In addition, earthworms were exposed (LC50) for 14 days in treated soil.In general, no toxic responses were evident. For northern bobwhite, the LD50 for all five chemicals was >2000 mg a.l./kg of body mass. American kestrels regurgitated all chemicals except Silv-ex; LD50s all exceeded 2000 mg/kg. The LD50 for red-winged blackbird was also >2000 mg/kg for all chemicals except Fire-Trol GTS-R which is currently undergoing further testing. In addition, the LD50 for white-footed mouse was >2000 mg/kg for Phos-Chek D75F. The 14-day LC50 for earthworms was >1000 ppm for all chemicals. Therefore, we concluded that these retardants and foams do not pose an acute hazard to adult birds, mammals, or earthworms. However, ecological studies to evaluate the potential effects of these formulations on vertebrate behavior and population dynamics are in progress.

  6. Properties and Performance of Rubberwood Particleboard Treated With Bp® Fire Retardant

    OpenAIRE

    Izran K.; Abood F.; Yap K. C.; Abdul Rashid A. M.; Zaidon A.

    2011-01-01

    Rubberwood composites are available in many sizes and are frequently used as furniture and partitioning inputs. However they are naturally combustible and may limit its usage for other value-added products. Treating wood composites with fire retardant was one of the most effective ways to prevent such occurrence. In this study, Rubberwood (Hevea brasiliensis) particleboards were incorporated with BP® fire retardant through hot and cold soaking processes. Four different concentrations of fire ...

  7. Improvement of flame resistance of non-flame retardant cables by applying fire protection measures

    International Nuclear Information System (INIS)

    Takemura, Yujiro; Segoshi, Yoshinori; Jinno, Susumu; Mii, Kazuki

    2017-01-01

    The new regulatory requirements, which were put in force after the Fukushima Daiichi accident, impose the use of flame retardant cables on the plant components having safety functions for the purpose of fire protection. However, some Japanese nuclear power plants built in the early days use non-flame retardant cables that do not pass the demonstration test to check for the flame resistance. To cope with the new regulatory requirements, a fire protection measure for non-flame retardant cables was introduced to assure flame resistance of non-flame retardant cables equivalent to or higher than that of flame retardant cables. To illustrate the fire protection measure, both non-flame retardant cables and its cable tray are covered with fire protection sheet fabricated from incombustible material to form an assembly. Considering the demonstration test results, it can be concluded that flame resistance performance of non-flame retardant cables equivalent to or higher than that of flame retardant cables can be assured by forming the assembly even if an external fire outside the assembly and internal cable fire inside the assembly are assumed. This paper introduces the design of the assembly consisting of a bundle of cables and a cable tray and summarizes the results of demonstration tests. (author)

  8. Fire performance, mechanical strength and dimensional stability of wood flour–polyethylene composites under the influence of different fire retardants

    Directory of Open Access Journals (Sweden)

    Mehdi Roohani

    2017-05-01

    Full Text Available Flammability is one of the most important parameters that often limit the application range of wood plastic composites. Therefore, the improvements of retardancy performance of these products have a considerable impact. The aim of this work was to evaluate the influence of expandable graphite (EG and its combination with aluminum tirhydroxide (ATH, inorganic phosphate (IP and melamine borate (MB on the flammability of wood flour–polyethylene composites. Composites were prepared by the melt compounding method and cone calorimetry as well as limited oxygen index (LOI tests was employed to study their flammability properties. Also, the effect of different fire retardants on the mechanical strength and water uptake of samples were investigated. Cone calorimetry characterization indicated that with incorporation of fire retardans heat release rate and burning rate decrease and char residual as well as the time to ignition increase. These findings ascribed to formation of char layer by fire retardants. The combination of EG and other fire retardants yielded better improvements in flame retardancy in comparison to the sample that has just EG as flame retardant. The LOI test was used to determine the lowest concentration of oxygen at which a material will maintain combustion in a flowing mixture of oxygen and nitrogen. The results showed that inclusion of fire retardants improve the LOI of sample. Furthermore, the presence of fire retardants decreased the tensile and flexural resistance (strength and modules and impact strength of samples, and increased the water absorption as well as thickness swelling. Generally, among the different treatments examined, the EG–ATH retardancy system showed highest potential in flame retardancy of composites.

  9. A NOVEL FIRE RETARDANT AFFECTS FIRE PERFORMANCE AND MECHANICAL PROPERTIES OF WOOD FLOUR-HIGH DENSITY POLYETHYLENE COMPOSITES

    Directory of Open Access Journals (Sweden)

    Mingzhu Pan,

    2012-02-01

    Full Text Available Wood flour-high density polyethylene (HDPE composites were prepared to investigate the effects of ammonium polyphosphate based fire retardant content (2, 4, 6, 8, and 10-wt%, on the flammability, mechanical, and morphological properties of the wood flour-HDPE composites in this study. Cone calorimetry analysis showed that the addition of fire retardant could decrease the heat release rate (HRR and total smoke release of wood flour-HDPE composites, while it had no obviously effects on effective heat of combustion. Most of the decrease of the HRR occurred with the concentration of the fire retardant up to 4-wt%. With addition of fire retardant, the composites showed a decrease in tensile elongation at break and impact strength, and had no obvious effect on tensile and flexural strength. The scanning electron microscopy observation on the fracture surface of the composites indicated that fire retardant had a uniform dispersion in the wood flour-HDPE composites. However, interfacial bonding would be suggested to improve in wood flour-HDPE composites with ammonium polyphosphate based fire retardant.

  10. Corrosion of Aluminum Alloys in the Presence of Fire-Retardant Aircraft Interior Materials

    Science.gov (United States)

    1995-10-01

    This research project was to evaluate the potential for fire-retardant materials used in aircraft interiors to cause corrosion of aluminum structural alloys. Service Difficulty Reports (SDR's) were reviewed for several aircraft types, and the most fr...

  11. The improvement for fire retardant and radiation resistance characteristics of chloroprene rubber

    Energy Technology Data Exchange (ETDEWEB)

    Kim, K. Y.; Lee, C.; Kim, P. J.; Kim, J. H

    2004-04-01

    In the report, in order to improve the fire retardancy better Chloroprene Rubber (CR) after adding each fixed amount of inorganic metallic hydroxide, and then compared and assessed fire retardancy with electrical properties and mechanical properties we intended to choose the most excellent additives. Also according to Co{sup 60} {gamma}-ray irradiation, we compared electrical, echanical and fire retardant characteristics to analyse to have the additives of inorganic filler effect on CR's antirad characteristic. In result, CR containing inorganic additive, advanced considerably fire retardant characteristics, but seems to be tended to declined electrical and mechanical characteristics on the whole. In syntherically comparison, the specimen viewed the most excellent characteristics is CR containing Magnesium hydroxide. As to Co{sup 60} {gamma}-ray irradiated Chloroprene rubber containing inorganic additives, fire retardant characteristic are improved, but electrical and mechanical properties are deteriorated as a function of radiation dose. Comparing before irradiation and after irradiation, the best inorganic filler into CR consider Magnesium hydroxide. In this report, in case of adding 30 phr of inorganic filler to CR we observed fire retardancy and radiation resistance characteristics change in according to the kinds of additives, but the research for choosing the optimum amount of additives is considered to progress from now on as adjusting the amount of additives presented excellent characteristics.

  12. The influence of fire retardants on the properties of beech and poplar veneers and plywood

    Directory of Open Access Journals (Sweden)

    Miljković Jovan

    2005-01-01

    Full Text Available Rising demands for fire resistance properties of wood construction and elements matching new standards have been an important part of building codes during the last decade. On the other side, lack of more detailed research on interaction between wood species and selected fire retardant chemicals even with basically one is evident. This is particularly truth with domestic wood species. In this research, beech and poplar veneers were immersed in 25% solutions of monoammonium phosphate (MP and sodium acetate (SA and impregnated for different periods of time. To determine the preliminary level of fire retardancy achieved in veneers before manufacturing of finished plywood, thermo gravimetric (TG and derivative thermo gravimetric (DTG methods were used. TG and DTG analyses of treated and untreated wood, as well as of fire retardants alone, were performed. The next properties of impregnated and no impregnated veneers and plywood were determined: absorption of imp regnant solution (A, weight percent gain (WPG of imp regnant, equilibrium moisture content (EMC, pH values, and in the case of plywood, strength and fire resistance. Fire resistance of plywood was tested in accordance with standard test for resistance to the effects of fire and the most efficient fire retardant, monoammonium phosphate, had the same result as TG/DTG analyses, which pointed out the validity of TG methods in predicting fire resistance of future products.

  13. Modification of poly(styrene-block-butadiene-block-styrene) [SBS] with phosphorus containing fire retardants

    DEFF Research Database (Denmark)

    Chernyy, Sergey; Ullah, Saif; Jomaas, Grunde

    2015-01-01

    An elaborate survey of the chemical modification methods for endowing highly flammable SBS with increased fire resistant properties by means of chemical modification of the polymer backbone with phosphorus containing fire retardant species is presented. Optimal conditions for free radical addition...

  14. Properties of flat-pressed wood plastic composites containing fire retardants

    Science.gov (United States)

    Nadir Ayrilmis; Jan. T. Benthien; Heiko Thoemen; Robert H. White

    2011-01-01

    This study investigated physical, mechanical, and fire properties of the flat-pressed wood plastic composites (WPCs) incorporated with various fire retardants (FRs) [5 or 15% by weight (wt)] at 50 wt % of the wood flour (WF). The WPC panels were made from dry-blended WF, polypropylene (PP) with maleic anhydride grafted PP (2 wt %), and FR powder formulations using a...

  15. Flame retardants in UK furniture increase smoke toxicity more than they reduce fire growth rate.

    Science.gov (United States)

    McKenna, Sean T; Birtles, Robert; Dickens, Kathryn; Walker, Richard G; Spearpoint, Michael J; Stec, Anna A; Hull, T Richard

    2018-04-01

    This paper uses fire statistics to show the importance of fire toxicity on fire deaths and injuries, and the importance of upholstered furniture and bedding on fatalities from unwanted fires. The aim was to compare the fire hazards (fire growth and smoke toxicity) using different upholstery materials. Four compositions of sofa-bed were compared: three meeting UK Furniture Flammability Regulations (FFR), and one using materials without flame retardants intended for the mainland European market. Two of the UK sofa-beds relied on chemical flame retardants to meet the FFR, the third used natural materials and a technical weave in order to pass the test. Each composition was tested in the bench-scale cone calorimeter (ISO 5660) and burnt as a whole sofa-bed in a sofa configuration in a 3.4 × 2.25 × 2.4 m 3 test room. All of the sofas were ignited with a No. 7 wood crib; the temperatures and yields of toxic products are reported. The sofa-beds containing flame retardants burnt somewhat more slowly than the non-flame retarded EU sofa-bed, but in doing so produced significantly greater quantities of the main fire toxicants, carbon monoxide and hydrogen cyanide. Assessment of the effluents' potential to incapacitate and kill is provided showing the two UK flame retardant sofa-beds to be the most dangerous, followed by the sofa-bed made with European materials. The UK sofa-bed made only from natural materials (Cottonsafe ® ) burnt very slowly and produced very low concentrations of toxic gases. Including fire toxicity in the FFR would reduce the chemical flame retardants and improve fire safety. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  16. The Effect of Particle Size of Wollastonite Filler on Thermal Performance of Intumescent Fire Retardant Coating

    Directory of Open Access Journals (Sweden)

    Zia-ul-Mustafa M.

    2014-07-01

    Full Text Available Intumescent Fire retardant coatings (IFRC’s are one of the simplest ways to protect substrates exposed to fire. In this study, Wollastonite (W filler of two different particle sizes were used to determine the fire performance of intumescent fire retardant coating. The basic ingredients of the coating were ammonium poly-phosphate (APP as acid source, expandable graphite (EG as carbon source, melamine (MEL as blowing agent in epoxy binder, boric acid as additive and hardener as curing agent. A series of coating formulations were developed by using different weight percentages of both sized Wollastonite fillers. The coated steel substrate samples were tested for fire performance using Bunsen burner and char expansion was measured using furnace fire test. A Comparison of the coatings thermal performance was determined. Wollastonite containing filler particle size 10 μm showed better thermal performance than formulations containing filler’s particle size 44 μm.

  17. Fire performance, microstructure and thermal degradation of an epoxy based nano intumescent fire retardant coating for structural applications

    Energy Technology Data Exchange (ETDEWEB)

    Aziz, Hammad, E-mail: engr.hammad.aziz03@gmail.com; Ahmad, Faiz, E-mail: faizahmad@petronas.com.my; Yusoff, P. S. M. Megat; Zia-ul-Mustafa, M. [Department of Mechanical Engineering, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Tronoh 31750, Perak (Malaysia)

    2015-07-22

    Intumescent fire retardant coating (IFRC) is a passive fire protection system which swells upon heating to form expanded multi-cellular char layer that protects the substrate from fire. In this research work, IFRC’s were developed using different flame retardants such as ammonium polyphosphate, expandable graphite, melamine and boric acid. These flame retardants were bound together with the help of epoxy binder and cured together using curing agent. IFRC was then reinforced with nano magnesium oxide and nano alumina as inorganic fillers to study their effect towards fire performance, microstructure and thermal degradation. Small scale fire test was conducted to investigate the thermal insulation of coating whereas fire performance was calculated using thermal margin value. Field emission scanning electron microscopy was used to examine the microstructure of char obtained after fire test. Thermogravimetric analysis was conducted to investigate the residual weight of coating. Results showed that the performance of the coating was enhanced by reinforcement with nano size fillers as compared to non-filler based coating. Comparing both nano size magnesium oxide and nano size alumina; nano size alumina gave better fire performance with improved microstructure of char and high residual weight.

  18. Acute toxicity of fire-retardant and foam-suppressant chemicals to yalella azteca (Saussure)

    Science.gov (United States)

    McDonald, Susan F.; Hamilton, Steven J.; Buhl, Kevin J.; Heisinger, James F.

    1997-01-01

    Acute toxicity tests were conducted with Hyalella azteca Saussure (an amphipod) exposed in soft and hard waters to three fire retardants (Fire-Trol GTS-R, Fire-Trol LCG-R, and Phos-Chek D75-F) and two foam suppressants (Phos-Chek WD-881 and Silv-Ex). The chemicals were slightly to moderately toxic to amphipods. The most toxic chemical to amphipods in soft and hard water was Phos-Chek WD-881 (96-h mean lethal concentration [LC50] equal to 10 mg/L and 22 mg/L, respectively), and the least toxic chemical to amphipods in soft water was Fire-Trol GTS-R (96-h LC50 equal to 127 mg/L) and in hard water was Fire-Trol LCG-R (96-h LC50 equal to 535 mg/L). Concentrations of ammonia in tests with the three fire retardants and both water types were greater than reported LC50 values and probably were the major toxic component. Estimated un-ionized ammonia concentrations near the LC50 were frequently less than the reported LC50 ammonia concentrations for amphipods. The three fire retardants were more toxic in soft water than in hard water even though ammonia and un-ionized ammonia concentrations were higher in hard water tests than in soft water tests. The accidental entry of fire-fighting chemicals into aquatic environments could adversely affect aquatic invertebrates, thereby disrupting ecosystem function.

  19. Application of fire-retardant treatment to the wood in Type A unirradiated nuclear fuel outer containers

    International Nuclear Information System (INIS)

    Whitlow, J.D.; Luna, R.E.

    1992-01-01

    Packagings for transporting unirradiated nuclear fuel assemblies in the United States are commonly constructed as rectangular boxes consisting of a metal inner container, a wooden outer container, and cushioning material separating the two. The wood in the outer container is a potential source of fuel for fire. Use of a fire-retardant treatment on the wood may reduce or eliminate the damage to nuclear fuel assemblies in some types of accidents involving fire. The applicability of using fire-retardant treatments on the wood of outer containers is addressed. An approximate cost-benefit analysis to determine if fire-retardant treatments are economically justified is presented. (Author)

  20. Fire retardancy assessment of polypropylene composite filed with nano clay prepared from Iraqi bentonite

    Science.gov (United States)

    Kareem Salih, Watheq

    2018-05-01

    Fire retardants have an extraordinary importance because of their role in saving the people, property and reducing the damages and minimizing the dangers resulting from fires and burning of polymeric composites which are used in different civil and industrial fields. The work in this paper can be divided into two main stages. In first one nano-clay was manufactured from Iraqi bentonite and it was characterized using AFM, XRD, XRF, SEM, and BET. The AFM test showed the particle size of prepared nano clay was about 99.25 nm. In the second stage, polypropylene/nano clay composites at three low loading percents (0%,2%,4%,6%) were formulated via twin screw extruder. The fire retardancy tests included burning rate according to ASTM:D-635 and maximum flame height of flame according to ASTM:D-3014. Besides, the mechanical tests and thermal behavior of prepared samples were investigated. The results showed that (4%) of nano-clay had the maximum fire retardancy and while at (2%) loading, the maximum value of tensile strength and Yong modulus were obtained. The maximum heat of fusion was recorded for 6% nano clay sample. The final results assessment confirmed on the possibility of using low loadings of prepared nano clay to improve the fire retardancy, mechanical and thermal properties successfully.

  1. Short Jute Fiber Reinforced Polypropylene Composites: Effect of Nonhalogenated Fire Retardants

    Directory of Open Access Journals (Sweden)

    Sk. Sharfuddin Chestee

    2017-01-01

    Full Text Available Short jute fiber reinforced polypropylene (PP composites were prepared using a single screw extrusion moulding. Jute fiber content in the composites is optimized with the extent of mechanical properties, and composites with 20% jute show higher mechanical properties. Dissimilar concentrations of several fire retardants (FRs, such as magnesium oxide (MO, aluminum oxide (AO, and phosphoric acid (PA, were used in the composites. The addition of MO, AO, and PA improved the fire retardancy properties (ignition time, flame height, and total firing time of the composites. Ignition time for 30% MO, flame height for 30% PA, and total firing time for 20% MO content composites showed good results which were 8 sec, 1 inch, and 268 sec, respectively. Mechanical properties (tensile strength, tensile modulus, bending strength, bending modulus, and elongation at break, degradation properties (soil test, weathering test, and percentage of weight loss, and water uptake were studied.

  2. Chemical regulation on fire: rapid policy advances on flame retardants.

    Science.gov (United States)

    Cordner, Alissa; Mulcahy, Margaret; Brown, Phil

    2013-07-02

    Chemicals that are widely used in consumer products offer challenges to product manufacturers, risk managers, environmental regulators, environmental scientists, and the interested public. However, the factors that cause specific chemicals to rise to the level of regulatory, scientific, and social movement concern and scrutiny are not well documented, and scientists are frequently unclear about exactly how their research impacts policy. Through a case study of advocacy around flame retardant chemicals, this paper traces the pathways through which scientific evidence and concern is marshaled by both advocacy groups and media sources to affect policy change. We focus our analysis around a broad coalition of environmental and public health advocacy organizations and an investigative journalism series published in 2012 in the Chicago Tribune. We demonstrate that the Tribune series both brought the issue to a wider public audience and precipitated government action, including state policy revisions and federal Senate hearings. We also show how a broad and successful flame retardant coalition developed, leveraged a media event, and influenced policy at multiple institutional levels. The analysis draws on over 110 in-depth interviews, literature and Web site reviews, and observations at a flame retardant manufacturing company, government offices, and scientific and advocacy conferences.

  3. Predicting bending strength of fire-retardant-treated plywood from screw-withdrawal tests

    Science.gov (United States)

    J. E. Winandy; P. K. Lebow; W. Nelson

    This report describes the development of a test method and predictive model to estimate the residual bending strength of fire-retardant-treated plywood roof sheathing from measurement of screw-withdrawal force. The preferred test methodology is described in detail. Models were developed to predict loss in mean and lower prediction bounds for plywood bending strength as...

  4. Change of mechanical properties of Norway Spruce wood due to degradation caused by fire retardants

    Czech Academy of Sciences Publication Activity Database

    Kloiber, Michal; Frankl, Jiří; Drdácký, Miloš; Kučerová, I.; Tippner, J.; Bryscejn, Jan

    2010-01-01

    Roč. 55, č. 4 (2010), s. 23-38 ISSN 1336-4561 Grant - others:GAČR(CZ) GA103/07/1091 Program:GA Institutional research plan: CEZ:AV0Z20710524 Keywords : wood degradation * fire retardant * mechanical properties * tensile strength * hardness Subject RIV: JN - Civil Engineering Impact factor: 0.284, year: 2010

  5. DOPO-VTS-based coatings in the realm of fire retardants for cotton textile

    DEFF Research Database (Denmark)

    Chernyy, Sergey; Ullah, Saif; Sørensen, Gitte

    2015-01-01

    The work elucidates the feasibility of incorporation of phosphorus-silicon containing fire retardant (10-(2-trimethoxysilylethyl)- 9-hydro-9-oxa-10-phosphaphenanthrene-10-oxide [DOPO-VTS]) into nanosol coating solutions by cohydrolysis cocondensation reaction of DOPO-VTS with tetraethoxysilane pr...

  6. Dispersion of borax in plastic is excellent fire-retardant heat insulator

    Science.gov (United States)

    Evans, H.; Hughes, J.; Schmitz, F.

    1967-01-01

    A mix of borax powder and a chlorinated anhydrous polyester resin yields a plastic composition that is fire-retardant, yields a minimum of toxic gases when heated, and exhibits high thermal insulating properties. This composition can be used as a coating or can be converted into laminated or cast shapes.

  7. Using kinetic models to predict thermal degradation of fire-retardant-treated plywood roof sheathing

    Science.gov (United States)

    Patricia Lebow; Jerrold E. Winandy; Patricia K. Lebow

    2003-01-01

    Between 1985-1995 a substantial number of multifamily housing units in the Eastern and Southern U.S. experienced problems with thermally degraded fire-retardant-treated (FRT) plywood roof sheathing. A series of studies conducted at the USDA Forest Service, Forest Products Laboratory (FPL), examined the materials, chemical mechanisms, and process implications and has...

  8. A Fire-Retardant Composite Made from Domestic Waste and PVA

    Directory of Open Access Journals (Sweden)

    Neni Surtiyeni

    2016-01-01

    Full Text Available We report the synthesis of a composite from domestic waste with the strength of wood building materials. We used original domestic waste with only a simple pretreatment to reduce the processing cost. The wastes were composed of organic components (generally originating from foods, paper, plastics, and clothes; the average fraction of each type of waste mirrored the corresponding fractions of wastes in the city of Bandung, Indonesia. An initial survey of ten landfills scattered through Bandung was conducted to determine the average fraction of each component in the waste. The composite was made using a hot press. A large number of synthesis parameters were tested to determine the optimum ones. The measured mechanical strength of the produced composite approached the mechanical properties of wood building materials. A fire-retardant powder was added to retard fire so that the composite could be useful for the construction of residential homes of lower-income people who often have problems with fire. Fire tests showed that the composites were more resistant to fire than widely used wood building materials.

  9. Ecofriendly Fire Retardant and Rot Resistance Finishing of Jute Fabric Using Tin and Boron Based Compound

    Science.gov (United States)

    Samanta, Ashis Kumar; Bagchi, Arindam

    2017-06-01

    Treatment with sodium stannate followed by treatment with boric acid imparts jute fabric wash fast fire resistance property as indicated by its Limiting Oxygen Index (LOI) value and 45° inclined flammability test results. The treatment was carried out by impregnation of sodium stannate followed by impregnation with an aqueous solution of boric acid and drying. Application of sodium stannate (20%) and boric acid (20%) treatment on jute fabric showed balanced flame retardancy property (LOI value 34) with some loss in fabric tenacity (loss of tenacity is 14.5%). Treated fabric retained good fire retardant property after three consecutive washing. Treated fabric also possessed good rot resistance property as indicated by soil burial test and strength retention after 21 days soil burial was found to be 65%. It is found that of sodium stannate and boric acid combination by double bath process form a synergistic durable fire-retardant as well as rot resistant when impregnated on jute material, which is considerably greater than the use of either sodium stannate or boric acid alone. TGA, FTIR and SEM analysis are also reported to support the results and reaction mechanism.

  10. Synergistic effects of mica and wollastonite fillers on thermal performance of intumescent fire retardant coating

    Energy Technology Data Exchange (ETDEWEB)

    Zia-ul-Mustafa, M., E-mail: engr.ziamustafa@gmail.com; Ahmad, Faiz; Megat-Yusoff, Puteri S. M.; Aziz, Hammad [Mechanical Engineering Department, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, 31750 Tronoh, Perak (Malaysia)

    2015-07-22

    In this study, intumescent fire retardant coatings (IFRC) were developed to investigate the synergistic effects of reinforced mica and wollastonite fillers based IFRC towards heat shielding, char expansion, char composition and char morphology. Ammonium poly-phosphate (APP) was used as acid source, expandable graphite (EG) as carbon source, melamine as blowing agent, boric acid as additive and Hardener H-2310 polyamide amine in bisphenol A epoxy resin BE-188(BPA) was used as curing agent. Bunsen burner fire test was used for thermal performance according to UL-94 for 1 h. Field Emission Scanning Electron Microscopy (FESEM) was used to observe char microstructure. X-Ray Diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) were used to analyse char composition. The results showed that addition of clay filler in IFRC enhanced the fire protection performance of intumescent coating. X-Ray Diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) results showed the presence of boron phosphate, silicon phosphate oxide, aluminium borate in the char that improved the thermal performance of intumescent fire retardant coating (IFRC). Resultantly, the presence of these developed compounds enhanced the Integrity of structural steel upto 500°C.

  11. Development of new radiation resistant, fire-retardant cables. [Gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Hagiwara, Ko; Morita, Yosuke; Udagawa, Takashi (Japan Atomic Energy Research Inst., Takasaki, Gunma. Takasaki Radiation Chemistry Research Establishment); Fujimura, Shun-ichi; Oda, Eisuke

    1982-12-01

    For the cables for nuclear facilities, radiation resistance and fire-retardation are severely required. The authors took note of the fact that even in the existing cables for nuclear power plants, their mechanical properties are greatly degraded by the exposure to large dose (for example, 200 Mrad in PWR testing conditions), and attempted the improvement. They employed a new additive, bromated acenaphthylene condensate (con-BACN), which effectively gives radiation resistance and also is a good flame retarder, to be compounded to an insulation material, and examined the characteristics. In this paper, the features of con-BACN and the investigation of fire-retardant EPDM composition are described. As an initial composition, a small amount of zinc white, sulphur, stearic acid, noclac 224 (Ouchi-Shinko Chemicals, Co.), and antimony trioxide, 100 parts of tale and 45 parts of con-BACN were added to 100 parts of EPDM (propylene content 34 %, Japan Synthetic Rubber Co.). As the antiaging agent, it was decided to use phenol series No. 3 as a result of test. The fire-retardant EP rubber-composed cable was produced for trial, its insulation being fabricated, using a Furukawa's pressurized salt bath continuous vulcanizer. The tests of ..gamma..-irradiation, simulated LOCA and combustion were carried out, and the test results are reported. It was indicated that the cable resisted against high dose several times as much as 200 Mrad, and was suitable for the applications, in which the mechanical properties such as bending are required to be maintained after radiation exposure. It was also found that con-BACN was safe, and its properties of decomposition, concentration and acute toxicity were all very low.

  12. Effect of Nano bentonite on Fire Retardant Properties of Medium density fiberboard (MDF

    Directory of Open Access Journals (Sweden)

    Ghonche Rassam

    2014-05-01

    Full Text Available In the present study, FireRetarding properties of nano-bentonite in medium density of fiberboard (MDF was studied. 10% of urea-formaldehyde resin was used as the adhesive of the matrix. Nano Bentonite at 5 levels (0%, 5%, 10%, 15% and 20% g/kg based of dry weight of fibers was used with the consumption of Urea-Formuldehyde (UF. Press pressure of 150 bar and temperature of 170during 4, 5, and 6 minutes were applied. Density was kept constant at 0.7 g/cm3 in all treatments. The measured properties consisted of mass reduction, inflammation time, fire-endurance, melting time and the burnt area. The results revealed that Nano-Bentonite had significant effect in approving fire retarding properties in medium density fiber board. The best properties at the level of 10% obtained and the same level recommended for industry use. The use of Nano-Bentonite more than 10% decreased the stickiness and the partly surface of fiberboards.

  13. Characterization of tea polyphenols as potential environment-friendly fire retardants

    Science.gov (United States)

    Yao, Fengqi; Zhai, Chunjie; Wang, Haihui; Tao, Junjun

    2018-02-01

    In this work we investigated the oxidation properties of tea polyphenols and their potential as the fire retardants. Two types of tea polyphenols were adopted, which were extracted from red tea and green tea leaves, respectively. Their macroscopic performance during pyrolysis and oxidation at elevated temperatures were examined by using a heating furnace. Mass change, heat evolution and gas products of tea polyphenols during heating in air were also monitored by using a thermo-gravimetric analyzer (TGA) integrated with a differential scanning calorimeter (DSC) in conjunction with online Fourier Transform Infrared Spectroscopy (FTIR) and mass spectroscopy (MS). A tea polyphenol sample first becomes a brown semi-fluid after heating, and gradually turns into highly-porous black chars with significantly expanded volume. By raising the temperature to ∼550 °C at a rate of 10 °C/min, the mass of a sample reduces by nearly 70% to form a large quantity of inert gases that are mainly composed of H2O and CO2. It was found that the aerial oxidation products of tea polyphenols in the solid phase possess good heat insulation property; meanwhile, the substantial release of a lot of water and its evaporation during oxidation of tea polyphenols removes a large amount of heat from a sample located in a heating environment. The heat insulation of tea polyphenols may withstand up to 550 °C. The present work confirms tea polyphenols as potential superior and environment-friendly fire retardants.

  14. Calculation of Limits of Fire Resistance for Structures with Fire Retardant Coating

    Directory of Open Access Journals (Sweden)

    Krivtcov Artem

    2016-01-01

    Full Text Available This article is devoted to fireproof processing of steel structures. The main task is to consider different types of sections of rod elements and to choose the most effective section for a steel column from the point of view of fire protection. For the solution of this task the steel columns with various cross sections working in identical entry conditions were considered. All necessary calculations for all types of sections were carried out. Results of calculations were presented in the summary table according to which the comparative analysis was made. At the end of work the conclusion that the compound section from four equal corners is the most effective from the point of view of fire protection.

  15. Synthesis and carbonization chemistry of a phosphorous–nitrogen based intumescent flame retardant

    International Nuclear Information System (INIS)

    Ma, Haiyun; Fang, Zhengping

    2012-01-01

    Graphical abstract: The carbonization chemistry and mechanism of a novel synthesized intumescent flame retardant. The final chars showed a complex P-O-Ph and aromatic/graphitic structure containing architecture. Highlights: ► The IFR synthesized is polymeric and has high molecular weight. ► The IFR has a higher thermal stability than most of the commercial IFRs. ► The final chars of IFR showed a complex P-O-Ph and aromatic/graphitic structure. - Abstract: In this work, a polymeric phosphorous–nitrogen containing intumescent flame retardant, named poly(diaminodiphenyl methane spirocyclic pentaerythritol bisphosphonate) (PDSPB), was synthesized. The carbonization chemistry was investigated. FTIR and 1 H NMR were used to confirm the chemical structure of PDSPB. Thermogravimetric analysis (TGA), scanning electron microscopy (SEM), transmission electron microscopy (TEM), in situ FTIR and energy dispersive X-ray (EDX) were used to investigate and monitor the chemical structural changes during thermal degradation. PDSPB demonstrated a three-step degradation behavior. PDSPB oligomers continuously polymerized and generated a higher macromolecular weight during the first step (200–250 °C). The phosphate ester bonds were broken down and phosphoric acid was released which dehydrated the carbon source to form chars during the second step (280–320 °C). The residues will be further degraded and form final chars during the final weight loss step (400–450 °C). The final chars showed a complex P-O-Ph and aromatic/graphitic structure containing architecture.

  16. Utilization of Magnesium Hydroxide Produced by Magnesia Hydration as Fire Retardant for Nylon 6-6,6

    Directory of Open Access Journals (Sweden)

    Rocha Sônia D.F.

    2001-01-01

    Full Text Available The present work investigates the use of magnesium hydroxide, produced by magnesia hydration, as a fire retardant in polymers. The hydration was carried out in an autoclave, at temperature of 130°C for 1 hour, and the product was further submitted to cominution in a jet mill. The solids were characterized with regard to their chemical composition, particle size distribution, surface area and morphology. The performance evaluation of the hydroxide as a flame retardant for a copolymer of nylon 6-6,6 was carried out according to the UL94 specifications for vertical burning tests. V-0 flammability rating at 1.6 mm (60% magnesium hydroxide-filled nylon composite and at 3.2 mm (40% magnesium hydroxide filled nylon composite were achieved. Mechanical properties were maintained at the desired values. These results indicate that the hydroxide obtained from magnesia hydration can be successfully employed as a fire retardant for nylon 6-6,6.

  17. Inhibition Effect of Phosphorus Flame Retardants on the Fire Disasters Induced by Spontaneous Combustion of Coal

    Directory of Open Access Journals (Sweden)

    Yibo Tang

    2017-01-01

    Full Text Available Coal spontaneous combustion (CSC generally induces fire disasters in underground mines, thus causing serious casualties, environmental pollution, and property loss around the world. By using six P-containing additives to process three typical coal samples, this study investigated the variations of the self-ignition characteristics of the coal samples before and after treatment. The analysis was performed by combining thermogravimetric analysis/differential scanning calorimetry (TG/DSC Fourier transform infrared spectrometer (FTIR and low temperature oxidation. Experimental results showed that P-containing inhibitors could effectively restrain the heat emitted in the combustion of coal samples and therefore the ignition temperature of the coal samples was delayed at varying degrees. The combustion rate of the coal samples was reduced as well. At the temperatures ranging from 50°C to 150°C, the activation energy of the coal samples after the treatment was found to increase, which indicated that the coal samples were more difficult to be oxidized. After being treated with phosphorus flame retardants (PFRs, the content of several active groups represented by the C-O structure in the three coal samples was proved to be obviously changed. This suggested that PFRs could significantly inhibit the content of CO generated by the low temperature oxidation of coal, and the flame-retardant efficiency grew with the increasing temperature. At 200°C, the maximal inhibition efficiency reached approximately 85%.

  18. The novel silicon-containing epoxy/PEPA phosphate flame retardant for transparent intumescent fire resistant coating

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Yanchao [School of Materials Science and Engineering, Tongji University, 4800 Cao' an Road, Shanghai 201804 (China); Wang, Guojian, E-mail: wanggj@tongji.edu.cn [School of Materials Science and Engineering, Tongji University, 4800 Cao' an Road, Shanghai 201804 (China); Key Laboratory of Advanced Civil Engineering Materials, Ministry of Education, 4800 Cao' an Road, Shanghai 201804 (China)

    2016-11-01

    Highlights: • The novel halogen-free flame retardant containing silicon and caged bicyclic phosphate was synthesized. • A novel transparent intumescent fire resistant coating was developed by the P-Si synergistic flame retardant and melamine formaldehyde resin. • Excellent fire protection of the transparent intumescent fire resistant coating. • The P-Si synergistic flame retardant could improve the thermo-oxidation resistance of transparent fire resistant coating. - Abstract: A series of novel silicon-containing epoxy/PEPA phosphate flame retardants (EPPSi) were synthesized by polyphosphoric acid (PPA), caged bicyclic phosphate 1-oxo-4-hydroxymethyl-2,6,7-trioxa-L-phosphabicyclo [2.2.2] octane (PEPA), and different ratios of silicon-containing epoxy 1,1,3,3-tetramethyl-1,3-bis(3-(oxiran-2-ylmethoxy)propyl)disiloxane (TMSEP) to 1,4-butanediol diglycidyl ether (BDE). The chemical structure of EPPSi was confirmed by Fourier transform infrared spectroscopy (FTIR) and {sup 1}H nuclear magnetic resonance spectroscopy ({sup 1}H NMR). Afterwards, the transparent intumescent fire resistant coatings were prepared by mixing EPPSi and melamine formaldehyde resin. The influence of silicon on the fire protection of coatings was intensively investigated by fire protection test, intumescence ratio, scanning electron microscope (SEM), compressive strength test, X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA) and real-time FTIR. It was found that the fire resistant coatings obtained the best fire protection when the ratio of TMESP/BDE was 20/100, while excessive TMSEP made the fire protection of coatings deceased sharply. The intumescence ratio, compressive strength test and SEM result showed that a synergistic effect existed between phosphorus and silicon, which improved the foam structure and compressive strength of the char layer significantly. XPS result proved the out-migration effect of silicon. The high concentration silicon on surface played

  19. Impact of a long-term fire retardant (Fire Trol 931) on the leaching of Ca, Mg, and K from a Mediterranean forest loamy soil.

    Science.gov (United States)

    Michalopoulos, Charalampos; Koufopoulou, Sofia; Tzamtzis, Nikolaos; Pappa, Athina

    2016-03-01

    The present laboratory study was conducted in pot soil taken from forest. The leaching of calcium (Ca), magnesium (Mg), and potassium (K) (plant macronutrients) due to the application of a nitrogen phosphate-based long-term fire retardant (LTFR) (Fire Trol 931) was investigated. The concentrations of Ca(2+), Mg(2+), and K(+) were measured in the resulting leachates from pots with forest soil and pine tree alone and in combination with fire. Magnesium is a minor component of Fire Trol 931. The leaching of Ca(2+), Mg(2+), and K(+) from treated soils with the retardant pots was significantly greater than that from control pots. The leaching of Mg(2+) was found to be of small percentage of the initially applied Mg quantities. Fire Trol 931 application resulted in the leaching of Ca(2+), Mg(2+), and K(+) from a typical Mediterranean forest soil in pots, following the application of simulated annual precipitation probably due to ammonium (one of the major retardant components) soil deposition that mobilizes base cations from the soil. It seems that LTFR application may result in chemical leaching from the soil to the drainage water.

  20. Synthesis and carbonization chemistry of a phosphorous-nitrogen based intumescent flame retardant

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Haiyun, E-mail: mahaiyun@gmail.com [College of Chemistry and Environmental Science, HeBei University, Baoding, Hebei Province 071002 (China); Fang, Zhengping [MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Institute of Polymer Composites, Zhejiang University, Hangzhou 310027 (China); Laboratory of Polymer Materials and Engineering, Ningbo Institute of Technology, Zhejiang University, Ningbo 315100 (China)

    2012-09-10

    Graphical abstract: The carbonization chemistry and mechanism of a novel synthesized intumescent flame retardant. The final chars showed a complex P-O-Ph and aromatic/graphitic structure containing architecture. Highlights: Black-Right-Pointing-Pointer The IFR synthesized is polymeric and has high molecular weight. Black-Right-Pointing-Pointer The IFR has a higher thermal stability than most of the commercial IFRs. Black-Right-Pointing-Pointer The final chars of IFR showed a complex P-O-Ph and aromatic/graphitic structure. - Abstract: In this work, a polymeric phosphorous-nitrogen containing intumescent flame retardant, named poly(diaminodiphenyl methane spirocyclic pentaerythritol bisphosphonate) (PDSPB), was synthesized. The carbonization chemistry was investigated. FTIR and {sup 1}H NMR were used to confirm the chemical structure of PDSPB. Thermogravimetric analysis (TGA), scanning electron microscopy (SEM), transmission electron microscopy (TEM), in situ FTIR and energy dispersive X-ray (EDX) were used to investigate and monitor the chemical structural changes during thermal degradation. PDSPB demonstrated a three-step degradation behavior. PDSPB oligomers continuously polymerized and generated a higher macromolecular weight during the first step (200-250 Degree-Sign C). The phosphate ester bonds were broken down and phosphoric acid was released which dehydrated the carbon source to form chars during the second step (280-320 Degree-Sign C). The residues will be further degraded and form final chars during the final weight loss step (400-450 Degree-Sign C). The final chars showed a complex P-O-Ph and aromatic/graphitic structure containing architecture.

  1. Study of the Thermal Properties and the Fire Performance of Flame Retardant-Organic PCM in Bulk Form.

    Science.gov (United States)

    Palacios, Anabel; De Gracia, Alvaro; Haurie, Laia; Cabeza, Luisa F; Fernández, A Inés; Barreneche, Camila

    2018-01-12

    The implementation of organic phase change materials (PCMs) in several applications such as heating and cooling or building comfort is an important target in thermal energy storage (TES). However, one of the major drawbacks of organic PCMs implementation is flammability. The addition of flame retardants to PCMs or shape-stabilized PCMs is one of the approaches to address this problem and improve their final deployment in the building material sector. In this study, the most common organic PCM, Paraffin RT-21, and fatty acids mixtures of capric acid (CA), myristic acid (MA), and palmitic acid (PA) in bulk, were tested to improve their fire reaction. Several flame retardants, such as ammonium phosphate, melamine phosphate, hydromagnesite, magnesium hydroxide, and aluminum hydroxide, were tested. The properties of the improved PCM with flame retardants were characterized by thermogravimetric analyses (TGA), the dripping test, and differential scanning calorimetry (DSC). The results for the dripping test show that fire retardancy was considerably enhanced by the addition of hydromagnesite (50 wt %) and magnesium hydroxide (50 wt %) in fatty acids mixtures. This will help the final implementation of these enhanced PCMs in building sector. The influence of the addition of flame retardants on the melting enthalpy and temperatures of PCMs has been evaluated.

  2. Study of the Thermal Properties and the Fire Performance of Flame Retardant-Organic PCM in Bulk Form

    Directory of Open Access Journals (Sweden)

    Anabel Palacios

    2018-01-01

    Full Text Available The implementation of organic phase change materials (PCMs in several applications such as heating and cooling or building comfort is an important target in thermal energy storage (TES. However, one of the major drawbacks of organic PCMs implementation is flammability. The addition of flame retardants to PCMs or shape-stabilized PCMs is one of the approaches to address this problem and improve their final deployment in the building material sector. In this study, the most common organic PCM, Paraffin RT-21, and fatty acids mixtures of capric acid (CA, myristic acid (MA, and palmitic acid (PA in bulk, were tested to improve their fire reaction. Several flame retardants, such as ammonium phosphate, melamine phosphate, hydromagnesite, magnesium hydroxide, and aluminum hydroxide, were tested. The properties of the improved PCM with flame retardants were characterized by thermogravimetric analyses (TGA, the dripping test, and differential scanning calorimetry (DSC. The results for the dripping test show that fire retardancy was considerably enhanced by the addition of hydromagnesite (50 wt % and magnesium hydroxide (50 wt % in fatty acids mixtures. This will help the final implementation of these enhanced PCMs in building sector. The influence of the addition of flame retardants on the melting enthalpy and temperatures of PCMs has been evaluated.

  3. Study of the Thermal Properties and the Fire Performance of Flame Retardant-Organic PCM in Bulk Form

    Science.gov (United States)

    Palacios, Anabel; De Gracia, Alvaro

    2018-01-01

    The implementation of organic phase change materials (PCMs) in several applications such as heating and cooling or building comfort is an important target in thermal energy storage (TES). However, one of the major drawbacks of organic PCMs implementation is flammability. The addition of flame retardants to PCMs or shape-stabilized PCMs is one of the approaches to address this problem and improve their final deployment in the building material sector. In this study, the most common organic PCM, Paraffin RT-21, and fatty acids mixtures of capric acid (CA), myristic acid (MA), and palmitic acid (PA) in bulk, were tested to improve their fire reaction. Several flame retardants, such as ammonium phosphate, melamine phosphate, hydromagnesite, magnesium hydroxide, and aluminum hydroxide, were tested. The properties of the improved PCM with flame retardants were characterized by thermogravimetric analyses (TGA), the dripping test, and differential scanning calorimetry (DSC). The results for the dripping test show that fire retardancy was considerably enhanced by the addition of hydromagnesite (50 wt %) and magnesium hydroxide (50 wt %) in fatty acids mixtures. This will help the final implementation of these enhanced PCMs in building sector. The influence of the addition of flame retardants on the melting enthalpy and temperatures of PCMs has been evaluated. PMID:29329212

  4. Development of Self Fire Retardant Melamine-Animal Glue Formaldehyde (MGF) Resin for the Manufacture of BWR Ply Board

    Science.gov (United States)

    Khatua, Pijus Kanti; Dubey, Rajib Kumar; Roymahapatra, Gourisankar; Mishra, Anjan; Shahoo, Shadhu Charan; Kalawate, Aparna

    2017-10-01

    Wood is one of the most sustainable, naturally growing materials that consist mainly of combustible organic carbon compounds. Since plywood are widely used nowadays especially in buildings, furniture and cabinets. Too often the fire behavior of ply-board may be viewed as a drawback. Amino-plastic based thermosetting resin adhesives are the important and most widely used in the plywood panel industries. The fire retardant property of wood panel products by adding animal glue as an additive in the form of MGF resin and used as substitute of melamine for manufacture of plywood. Environment concerns and higher cost of petroleum based resins have resulted in the development of technologies to replace melamine partially by biomaterials for the manufacturing of resin adhesive. Natural bio-based materials such as tannin, CNSL (cardanol), lignin, soya etc. are used as partial substitution of melamine. This article presents the development of melamine-animal glue formaldehyde resin as plywood binder. About 30 % melamine was substituted by animal glue and optimized. The different physico-mechanical and fire retardant property properties tested as per IS: 1734-1983 and IS: 5509-2000 respectively are quite satisfactory. The production of adhesive from melamine with compatible natural proteinous material is cost effective, eco-friendly and enhance the fire retardant property.

  5. Effect of Magnesium Borates on the Fire-Retarding Properties of Zinc Borates

    Directory of Open Access Journals (Sweden)

    Azmi Seyhun Kipcak

    2014-01-01

    Full Text Available Magnesium borate (MB is a technical ceramic exhibiting high heat resistance, corrosion resistance, great mechanical strength, great insulation properties, lightweightness, high strength, and a high coefficient of elasticity. Zinc borate (ZB can be used as a multifunctional synergistic additive in addition to flame retardant additives in polymers. In this study, the raw materials of zinc oxide (ZnO, magnesium oxide (MgO, and boric acid (H3BO3 were used in the mole ratio of 1 : 1 : 9, which was obtained from preexperiments. Using the starting materials, hydrothermal synthesis was applied, and characterisation of the products was performed using X-Ray diffraction (XRD and Fourier transform infrared (FT-IR and Raman spectroscopies. The forms of Zn3B6O12·3.5H2O, MgO(B2O33·7(H2O, and Mg2(B6O7(OH62·9(H2O were synthesised successfully. Moreover, the surface morphology was investigated using scanning electron microscopy (SEM, and the B2O3 content was determined. In addition, the reaction yields were calculated. The results of the B2O3 content analysis were in compliance with the literature values. Examination of the SEM images indicated that the obtained nanoscale minerals had a reaction efficiency ranging between 63–74% for MB and 87–98% for ZB. Finally, the fire-retarding properties of the synthesised pure MBs, pure ZBs, and mixtures of MB and ZB were determined using differential thermal analysis and thermal gravimetry (DTA-TG and differential scanning calorimetry (DSC.

  6. Chemistry experiences from a containment fire at Ringhals unit 2

    International Nuclear Information System (INIS)

    Arvidsson, Bengt; Svanberg, Pernilla; Bengtsson, Bernt

    2012-09-01

    At the refuelling outage in Ringhals unit 2, during an ongoing Containment Air Test (CAT), a fire event occurred at the refuelling deck/entrance floor. Due to the ongoing CAT with high pressure, all attempts to enter the containment to extinguish the fire were impossible. The fire started as a short circuit (spark) in a vacuum cleaner that was left in the containment by mistake and then set fire to nearby material. Approximate, 5 kg of rubber material and 30 kg of plastic material were estimated to have been burned out. The complete inside of the containment from the level of fire (+115) up to the ceiling/dome (+156) was colored black by soot. Soot or smoke was also spread throughout the whole containment building and the cavity/reactor vessel was contaminated by a minor part of soot due to some unsuccessful covering of the area during CAT. All fuel assemblies were stored in the fuel pool building and not affected by the fire. During the pressure reduction of containment, high air humidity with moisture precipitation occurred and caused a rapid general corrosion on steel surfaces due to high levels of chloride in the soot together with some pitting on stainless steel piping. Immediate action was to install portable dryers to lower the humidity, followed by the start of an extensive cleaning program with objectives to prevent plant degradation/recontamination of soot and bring the unit back in operation. More than 1300 people including >150 cleaners has been appointed to this project. All piping, insulation, cables, >4.500 components, 6.340 m 2 of concrete wall surface and 5.100 m 2 of concrete floor surface have been cleaned during 7 months to an estimated cost of 20 million Euro. Chemistry staff has been deeply involved in sampling and chemical analysis of contaminated surfaces/objects as well as establishing criteria's for cleaning equipment, procedures and specifications. Approximately 12000 measurements have been performed using portable salt meters in

  7. Brominated flame retardants and the formation of dioxins and furans in fires and combustion

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Mengmei [State key laboratory of clean energy utilisation, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou (China); Buekens, Alfons [State key laboratory of clean energy utilisation, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou (China); Formerly with Chemical Engineering department, Vrije Universiteit Brussel, Brussels (Belgium); Li, Xiaodong, E-mail: lixd@zju.edu.cn [State key laboratory of clean energy utilisation, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou (China)

    2016-03-05

    Highlights: • BFRs (PBDEs, HBCD and TBBP-A) are the main sources of PBDD/Fs in combustion process. • Precursor formation is the most relevant pathway for PBDD/Fs formation. • Adding bromine into combustion system can enhance the formation of PCDD/Fs. • Primitive recycling of e-waste produces the largest amounts of PBDD/Fs. - Abstract: The widespread use and increasing inventory of brominated flame retardants (BFRs) have caused considerable concern, as a result of BFRs emissions to the environment and of the formation of both polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs) and mixed polybromochloro-dibenzo-p-dioxins and dibenzofurans (PBCDD/Fs or PXDD/Fs). Structural similarities between PBDD/Fs and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) suggest the existence of comparable formation pathways of both PBDD/Fs and PCDD/Fs, yet BFRs also act as specific precursors to form additional PBDD/Fs. Moreover, elementary bromine (Br{sub 2}) seems to facilitate chlorination by bromination of organics, followed by Br/Cl-exchange based on displacement through the more reactive halogen. Overall, PBDD/Fs form through three possible pathways: precursor formation, de novo formation, and dispersion of parts containing BFRs as impurities and surviving a fire or other events. The present review summarises the formation mechanisms of both brominated (PBDD/Fs) and mixed dioxins (PXDD/Fs with X = Br or Cl) from BFRs, recaps available emissions data of PBDD/Fs and mixed PXDD/Fs from controlled waste incineration, uncontrolled combustion sources and accidental fires, and identifies and analyses the effects of several local factors of influence, affecting the formation of PBDD/Fs and mixed PXDD/Fs during BFRs combustion.

  8. Thermally insulating and fire-retardant lightweight anisotropic foams based on nanocellulose and graphene oxide

    Science.gov (United States)

    Wicklein, Bernd; Kocjan, Andraž; Salazar-Alvarez, German; Carosio, Federico; Camino, Giovanni; Antonietti, Markus; Bergström, Lennart

    2015-03-01

    High-performance thermally insulating materials from renewable resources are needed to improve the energy efficiency of buildings. Traditional fossil-fuel-derived insulation materials such as expanded polystyrene and polyurethane have thermal conductivities that are too high for retrofitting or for building new, surface-efficient passive houses. Tailored materials such as aerogels and vacuum insulating panels are fragile and susceptible to perforation. Here, we show that freeze-casting suspensions of cellulose nanofibres, graphene oxide and sepiolite nanorods produces super-insulating, fire-retardant and strong anisotropic foams that perform better than traditional polymer-based insulating materials. The foams are ultralight, show excellent combustion resistance and exhibit a thermal conductivity of 15 mW m-1 K-1, which is about half that of expanded polystyrene. At 30 °C and 85% relative humidity, the foams retained more than half of their initial strength. Our results show that nanoscale engineering is a promising strategy for producing foams with excellent properties using cellulose and other renewable nanosized fibrous materials.

  9. Palm-Based Polyurethane with Soybean Phosphate Ester as a Fire Retardant

    International Nuclear Information System (INIS)

    Nor Rabbiatul Adawiyah Norzali; Khairiah Badri; Khairiah Badri; Ping, O.S.; Ishak Ahmad; Ishak Ahmad

    2014-01-01

    Palm-based polyurethane (PU) with soybean oil phosphate ester (PE) as a fire retardant was prepared. The effect of PE to the mechanical and burning properties of the PU was investigated. The PE was synthesized via ring-opening hydrolysis between o-phosphoric acid (o-H 3 PO 4 ) and epoxidized soybean oil. The synthesis was conducted at 60-70 degree Celsius. The concentration of o-H 3 PO 4 was varied at 2.5, 5.0 and 7.5 wt %. PE with 2.5 wt % H 3 PO 4 showed the lowest acid value (2.8 mgg -1 ) but high hydroxyl value (351.6 mgg -1 ) PU containing PE (PU-PE) has higher density (60-61 kgm -3 ) compared to control PU (49.7 kgm -3 ). Burning rate decreased from 2.16 x 10 -3 ms -1 for control PU to 1.26 x 10 -3 ms -1 , 1.06 x 10 -3 ms -1 and 0.6 x 10 -3 ms -1 for PU-PE at 5, 10 and 15 wt % PE respectively. However, the addition of PE into the PU system gradually decreased the compression stress and modulus of the PU-PE. (author)

  10. Advances in Research on the Venom Chemistry of Imported Fire Ants

    Science.gov (United States)

    Workers of the imported fire ants, including red imported fire ants, Solenopsis invicta Buren, black imported fire ants, S. richteri Forel, and their hybrid (S. invicta × S. richteri), are vicious stingers. Since the venomous sting is a significant medical problem to humans, the chemistry of import...

  11. Nighttime NOx Chemistry in Coal-Fired Power Plant Plumes

    Science.gov (United States)

    Fibiger, D. L.; McDuffie, E. E.; Dube, W. P.; Veres, P. R.; Lopez-Hilfiker, F.; Lee, B. H.; Green, J. R.; Fiddler, M. N.; Ebben, C. J.; Sparks, T.; Weinheimer, A. J.; Montzka, D.; Campos, T. L.; Cohen, R. C.; Bililign, S.; Holloway, J. S.; Thornton, J. A.; Brown, S. S.

    2015-12-01

    Nitrogen oxides (NOx = NO + NO2) play a key role in atmospheric chemistry. During the day, they catalyze ozone (O3) production, while at night they can react to form nitric acid (HNO3) and nitryl chloride (ClNO2) and remove O3 from the atmosphere. These processes are well studied in the summer, but winter measurements are more limited. Coal-fired power plants are a major source of NOx to the atmosphere, making up approximately 30% of emissions in the US (epa.gov). NOx emissions can vary seasonally, as well as plant-to-plant, with important impacts on the details of the plume chemistry. In particular, due to inefficient plume dispersion, nighttime NOx emissions from power plants are held in concentrated plumes, where rates of mixing with ambient O3 have a strong influence on plume evolution. We will show results from the aircraft-based WINTER campaign over the northeastern United States, where several nighttime intercepts of power plant plumes were made. Several of these intercepts show complete O3 titration, which can have a large influence on NOx lifetime, and thus O3 production, in the plume. When power plant NO emissions exceed background O3 levels, O3 is completely consumed converting NO to NO2. In the presence of O3, NO2 will be oxidized to NO3, which will then react with NO2 to form N2O5, which can then form HNO3 and/or ClNO2 and, ultimately, remove NOx from the atmosphere or provide next-day oxidant sources. If there is no O3 present, however, no further chemistry can occur and NO and NO2 will be transported until mixing with sufficient O3 for higher oxidation products. Modeling results of plume development and mixing, which can tell us more about this transport, will also be presented.

  12. Synthesis and characterization of non halogen fire retardant composite through combination of epoxy resin, Al(OH)3 additive and filler

    Science.gov (United States)

    Saputra, Asep Handaya; Sungkar, Faraj

    2017-11-01

    Epoxy has a wide range of applications in many sectors, but it still has deficiency in fire retardancy. Therefore, it is combined with fire retardant additives. Fire retardant additive commonly contains halogen compounds that causes environmental and health problems. Therefore Al (OH)3 additive is used to improve the fire retardancy properties of composite through decomposition that produced water vapour and formation of oxide layer on its surface. In this research, synthesis of fire retardant composite has been conducted by varying filler carbon black and silica (1%, 2.5%, 5%, 7.5%, 10%wt) with composition of Al (OH)3 50%wt and epoxy 50%wt. Fire retardancy of composite was observed by UL-94V standard, while thermal degradation behaviour of composite was analyzed by thermal gravimetric analysis and differential scanning calorimetry. Whereas, mechanical properties was studied based on its tensile strength and hardness. It was found that the best concentration for carbon black and silica is 1%wt and 2.5%wt respectively. The addition of carbon black 1%wt and silica 2.5%wt could improve the flame retardancy and gives V-0 flammability rating. Besides that, the addition of carbon black 1%wt is able to increase the thermal stability of composite by reducing mass loss rate until 10.75%/minute and total mass loss until 53.76%. While adding silica 2.5%wt could also enhance its thermal stability by decreasing mass loss rate until 9.32%/minute and total mass loss until 51.06%. Furthermore, the addition of carbon black and silica could decrease its tensile strength and hardness. The addition of carbon black 1%wt yields composite with 6.59 MPa for tensile strength and 65.8 shore D for hardness. Whereas the addition of of silica 2.5%wt produces composite with the tensile strength up to 9.89MPa and hardness up to71.2 shore D.

  13. Effects of alpha-zirconium phosphate on thermal degradation and flame retardancy of transparent intumescent fire protective coating

    Energy Technology Data Exchange (ETDEWEB)

    Xing, Weiyi [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzai Road, Hefei, Anhui 230026 (China); Zhang, Ping [State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, Southwest University of Science and Technology, 59 Qinglong Road, Mianyang 621010 (China); Song, Lei; Wang, Xin [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzai Road, Hefei, Anhui 230026 (China); Hu, Yuan, E-mail: yuanhu@ustc.edu.cn [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzai Road, Hefei, Anhui 230026 (China)

    2014-01-01

    Graphical abstract: - Highlights: • A transparent intumescent fire protective coating was obtained by UV-cured technology. • OZrP could enhance the thermal stability and anti-oxidation of the coating. • OZrP could reduce the combustion properties of the coatings. - Abstract: Organophilic alpha-zirconium phosphate (OZrP) was used to improve the thermal and fire retardant behaviors of the phenyl di(acryloyloxyethyl)phosphate (PDHA)-triglycidyl isocyanurate acrylate (TGICA)-2-phenoxyethyl acrylate (PHEA) (PDHA-TGICA-PHEA) coating. The morphology of nanocomposite coating was characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The effect of OZrP on the flame retardancy, thermal stability, fireproofing time and char formation of the coatings was investigated by microscale combustion calorimeter (MCC), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), laser Raman spectroscopy (LRS) and scanning electric microscope (SEM). The results showed that by adding OZrP, the peak heat release rate and total heat of combustion were significantly reduced. The highest improvement was achieved with 0.5 wt% OZrP. XPS analysis indicated that the performance of anti-oxidation of the coating was improved with the addition of OZrP, and SEM images showed that a good synergistic effect was obtained through a ceramic-like layer produced by OZrP covered on the surface of char.

  14. Effects of alpha-zirconium phosphate on thermal degradation and flame retardancy of transparent intumescent fire protective coating

    International Nuclear Information System (INIS)

    Xing, Weiyi; Zhang, Ping; Song, Lei; Wang, Xin; Hu, Yuan

    2014-01-01

    Graphical abstract: - Highlights: • A transparent intumescent fire protective coating was obtained by UV-cured technology. • OZrP could enhance the thermal stability and anti-oxidation of the coating. • OZrP could reduce the combustion properties of the coatings. - Abstract: Organophilic alpha-zirconium phosphate (OZrP) was used to improve the thermal and fire retardant behaviors of the phenyl di(acryloyloxyethyl)phosphate (PDHA)-triglycidyl isocyanurate acrylate (TGICA)-2-phenoxyethyl acrylate (PHEA) (PDHA-TGICA-PHEA) coating. The morphology of nanocomposite coating was characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The effect of OZrP on the flame retardancy, thermal stability, fireproofing time and char formation of the coatings was investigated by microscale combustion calorimeter (MCC), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), laser Raman spectroscopy (LRS) and scanning electric microscope (SEM). The results showed that by adding OZrP, the peak heat release rate and total heat of combustion were significantly reduced. The highest improvement was achieved with 0.5 wt% OZrP. XPS analysis indicated that the performance of anti-oxidation of the coating was improved with the addition of OZrP, and SEM images showed that a good synergistic effect was obtained through a ceramic-like layer produced by OZrP covered on the surface of char

  15. Mechanical properties and fire retardancy of bidirectional reinforced composite based on biodegradable starch resin and basalt fibres

    Directory of Open Access Journals (Sweden)

    2008-11-01

    Full Text Available Environmental problems caused by extensive use of polymeric materials arise mainly due to lack of landfill space and depletion of finite natural resources of fossil raw materials, such as petroleum or natural gas. The substitution of synthetic petroleum-based resins with natural biodegradable resins appears to be one appropriate measure to remedy the above-mentioned situation. This study presents the development of a composite that uses environmentally degradable starch-based resin as matrix and basalt fibre plain fabric as reinforcement. Prepreg sheets were manufactured by means of a modified doctor blade system and a hot power press. The sheets were used to manufacture bidirectional-reinforced specimens with fibre volume contents ranging from 33 to 61%. Specimens were tested for tensile and flexural strength, and exhibited values of up to 373 and 122 MPa, respectively. Through application of silane coupling agents to the reinforcement fibres, the flexural composite properties were subsequently improved by as much as 38%. Finally, in order to enhance the fire retardancy and hence the applicability of the composite, fire retardants were applied to the resin, and their effectiveness was tested by means of flame rating (according to UL 94 and thermogravimetric analysis (TGA, respectively.

  16. Application of thermal analysis methods on the study of PE thermal degradation and the influence of Mg (OH) sub 2 as fire retardant

    CERN Document Server

    Zarringhalam-Moghaddam, A

    2002-01-01

    Fire retardation effects of Mg(OH) sub 2 on PE was studied utilizing DTA, TGA and DSC methods. Reductions on reaction peak area and mass loss rate with the addition of Mg(OH) sub 2 were observed as indication of retardation effects of Mg(OH) sub 2 on PE. Cone calorimeter tests were performed on samples to verify the thermo analytical results. It was concluded that when Mg(OH) sub 2 is present it effectively modified the degradation behavior of PE and the thermal analyses are useful and rapid methods to study the retardation effects.

  17. Evaluation of various fire retardants for use in wood flour--polyethylene composites

    Science.gov (United States)

    Nicole M. Stark; Robert H. White; Scott A. Mueller; Tim A. Osswald

    2010-01-01

    Wood-plastic composites represent a growing class of materials used by the residential construction industry and the furniture industry. For some applications in these industries, the fire performance of the material must be known, and in some cases improved. However, the fire performance of wood-plastic composites is not well understood, and there is little...

  18. The influence of wildfire extent and severity on streamwater chemistry, sediment and temperature following the Hayman Fire, Colorado

    Science.gov (United States)

    Charles C. Rhoades; Deborah Entwistle; Dana Butler

    2011-01-01

    The 2002 Hayman Fire was the largest fire in recent Colorado history (558 km2). The extent of high severity combustion and possible effects on Denver's water supply focussed public attention on the effects of wildfire on water quality.Wemonitored stream chemistry, temperature and sediment before the fire and at monthly intervals for 5 years after the fire. The...

  19. Effect of fire retardants on cotton fabric grafted with acrylic acid by EB radiation: a thermal analysis study

    International Nuclear Information System (INIS)

    Mitra, D.; Sabharwal, S.; Majali, A.B.

    1998-01-01

    Electron beam irradiation technique has been utilized to graft acrylic acid to cotton fabric in order to provide suitable functional groups that can subsequently react with urea or borax for making the fabric fire resistant. Thermal analytical technique such as, DSC and TG have been utilized to investigate the flame retardency characteristic of the grafted and treated fabric. The result shows that decay curve of exothermic peak due to combustion of cotton fabric in case of urea treated fabric at 330 degC becomes broad and shifts to higher temperature in DSC analysis as compared to pure cotton fabric and char residue in TG analysis is 20% in both the case. In borax treated fabric, char residue is found to be 40% in TG analysis and DSC profile is similar to that of urea treated fabric. (author)

  20. Fire retardancy and environmental assessment of rubbery blends of recycled polymers

    Directory of Open Access Journals (Sweden)

    2008-02-01

    Full Text Available Flame retarded thermoplastic polymer compounds were prepared containing recycled rubber tyres, low density polyethylene, ethylene vinyl acetate copolymer and an intumescent additive system consisting of waste polyurethane foam and ammonium polyphosphate. The effect of the additives on the combustion properties was characterised by Limiting Oxygen Index, UL 94 and mass loss calorimetric measurements. The environmental impact was estimated by determining the gas components of CO2 and CO evolving from the compounds during the burning process using a gas analyser system constructed by coupling an FTIR unit to a mass loss calorimeter. The new material forms a thermoplastic rubber of excellent processability making it suitable for application in construction industry.

  1. Influence of expandable graphite on fire resistance and water resistance of flame-retardant coatings

    International Nuclear Information System (INIS)

    Wang, Zhenyu; Han, Enhou; Ke, Wei

    2007-01-01

    Expandable graphite (EG) coating and ammonium polyphosphate-pentaerythritol-melamine (APP-PER-MEL) coating were prepared. Thermal degradation and char formation of the coatings were investigated by differential thermal analysis (DTA), thermogravimetry (TG), X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The results have shown that the anti-oxidation and fire-resistant properties of expandable graphite coating containing EG with size of 74 μm are better than those of APP-PER-MEL coating. The static immersion test was applied to study water resistance of the coatings, and the fire protection test and mechanical test were used to analyse heat insulation and mechanical properties of coatings before and after water immersion. The fire-resistant and mechanical properties of APP-PER-MEL coating were severely damaged by water immersion, whereas EG coating containing 8.5% EG with size of 74 μm could retain the good fire resistance even after 500 h water immersion

  2. Toxic Combustion Product Yields as a Function of Equivalence Ratio and Flame Retardants in Under-Ventilated Fires: Bench-Large-Scale Comparisons

    Directory of Open Access Journals (Sweden)

    David A. Purser

    2016-09-01

    Full Text Available In large-scale compartment fires; combustion product yields vary with combustion conditions mainly in relation to the fuel:air equivalence ratio (Φ and the effects of gas-phase flame retardants. Yields of products of inefficient combustion; including the major toxic products CO; HCN and organic irritants; increase considerably as combustion changes from well-ventilated (Φ < 1 to under-ventilated (Φ = 1–3. It is therefore essential that bench-scale toxicity tests reproduce this behaviour across the Φ range. Yield data from repeat compartment fire tests for any specific fuel show some variation on either side of a best-fit curve for CO yield as a function of Φ. In order to quantify the extent to which data from the steady state tube furnace (SSTF [1]; ISO TS19700 [2] represents compartment fire yields; the range and average deviations of SSTF data for CO yields from the compartment fire best-fit curve were compared to those for direct compartment fire measurements for six different polymeric fuels with textile and non-textile applications and for generic post-flashover fire CO yield data. The average yields; range and standard deviations of the SSTF data around the best-fit compartment fire curves were found to be close to those for the compartment fire data. It is concluded that SSTF data are as good a predictor of compartment fire yields as are repeat compartment fire test data.

  3. Development tendencies in cycle chemistry of fossil fired power plants

    Energy Technology Data Exchange (ETDEWEB)

    Daucik, K [Skaerbaekvaerket, Faelleskemikerne, Fredericia (Denmark)

    1996-12-01

    The development of cycle chemistry during the past 50 years is described and the main tendencies are pointed out. Improvement of cycle purity is the most dominant evolution, which introduces more freedom with respect to pH and redox potential control. Units with once-through boilers have profited most from this development. The development of boiler water chemistry in drum boilers also tends towards higher purity and less chemicals, which raises possibilities for oxygenated treatment. (au)

  4. Thermal performance of glass fiber reinforced intumescent fire retardant coating for structural applications

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Faiz, E-mail: faizahmad@petronas.com.my; Ullah, Sami; Aziz, Hammad, E-mail: engr.hammad.aziz03@gmail.com; Omar, Nor Sharifah [Department of Mechanical Engineering, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Tronoh 31750 Perak (Malaysia)

    2015-07-22

    The results of influence of glass fiber addition into the basic intumescent coating formulation towards the enhancement of its thermal insulation properties are presented. The intumescent coatings were formulated from expandable graphite, ammonium polyphosphate, melamine, boric acid, bisphenol A epoxy resin BE-188, polyamide amine H-2310 hardener and fiberglass (FG) of length 3.0 mm. Eight intumescent formulations were developed and the samples were tested for their fire performance by burning them at 450°C, 650°C and 850°C in the furnace for two hours. The effects of each fire test at different temperatures; low and high temperature were evaluated. Scanning Electron Microscope, X-Ray Diffraction technique and Thermo Gravimetric Analysis were conducted on the samples to study the morphology, the chemical components of char and the residual weight of the coatings. The formulation, FG08 containing 7.0 wt% glass fiber provided better results with enhanced thermal insulation properties of the coatings.

  5. Fire-retardant Polyester Composites from Recycled Polyethylene Terephthalate (PET) Wastes Reinforced with Coconut Fibre

    International Nuclear Information System (INIS)

    Nurul Munirah Abdullah; Ishak Ahmad

    2013-01-01

    Coconut fibre reinforced composite was prepared by blending unsaturated polyester resin (UPR) from waste PET with 0.3 v % of coconut fibre. The coconut fibres were pre-treated with sodium hydroxide followed by silane prior to inclusion into the UPR. The untreated coconut fibres reinforced composite were used as a control. DriconR as a phosphate type of flame retardant was then added to the composite to reduce the flammability of the composite. The amount of DriconR was varied from 0 to 10 wt % of the overall mass of resin. The burning properties and limiting oxygen index (LOI) of the treated and untreated composites increased with the addition of Dricon. The tensile strength and modulus of both composites were also increased with the addition of DriconR. The treated fibre composite with 5 wt % DriconR showed the highest burning time and LOI with the values of 101.5 s and 34 s, respectively. The optimum tensile strength and modulus for treated fibre composite was at 5 wt % DriconR whereas the untreated fibre composite was at 2.5 wt % loading of DriconR. Thermogravimetry (TGA) analysis indicated that the degradation temperature increased with the addition of DriconR up to 5 wt % into UPR/ coconut fibre composites. Morphological observations indicated better distribution of DriconR for treated fibre composite resulted in enhancement of the tensile properties of the treated fibre composite. (author)

  6. THE COMBINED EFFECT OF ORGANIC PHOSPHINATE BASED FLAME RETARDANT AND ZINC BORATE ON THE FIRE BEHAVIOR OF POLY(BUTYLENE TEREPHTHALATE

    Directory of Open Access Journals (Sweden)

    Mustafa Erdem ÜREYEN

    2016-12-01

    Full Text Available Neat poly(butylene terephthalate is highly combustible. It is not self-extinguishing, and after ignition it burns with dripping. To meet the fire safety requirements, it should be rendered flame retardant. The most common flame retardants for PBT are based on halogenated (most often brominated or phosphorus compounds. Although their efficiency is lower than halogen based flame retardants, expensive phosphorus based flame retardants for polyester are preferred, because of low smoke generation, nontoxicity and low corrosion properties. Zinc borate has been widely used with other flame retardants in wood products and in several polymers. In this work the fire behavior of zinc borate, phosphinic acid and zinc borate/phosphinic acid combination doped poly(butylene terephthalate was investigated. Firstly, the mean particle size of zinc borate (2ZnO.3B2O3.3.5H2O powders were reduced by attrition milling. Samples were produced by twin screw micro compounder. The fire properties of the ZnB, DPA and ZnB/DPA doped PBT were investigated and compared to each other by LOI and thermal analysis. LOI values of ZnB/PBT samples were found very low even with higher filling content. At higher loading of ZnB, the dripping of the sample strongly decreased and char residue increased. It was seen that organic diethyl phosphinic acid based additives DPA is particularly effective with PBT. It was found that the combination of DPA and ZnB can be used to increase the char residue, decrease spread of flame and the melt dripping of PBT.

  7. Impact of a long term fire retardant (Fire Trol 931) on the leaching of Na, Al, Fe, Mn, Cu and Si from a Mediterranean forest soil: a short-term, lab-scale study.

    Science.gov (United States)

    Koufopoulou, Sofia; Michalopoulos, Charalampos; Tzamtzis, Nikolaos; Pappa, Athina

    2014-06-01

    Long term fire retardant (LTR) application for forest fire prevention purposes as well as wildland fires can result in chemical leaching from forest soils. Large quantities of sodium (Na), aluminium (Al), iron (Fe), manganese (Mn), copper (Cu) and silicon (Si) in leachates, mainly due to ammonium (one of the major LTR components) soil deposition, could affect the groundwater quality. The leaching of Na, Al, Fe, Mn, Cu and Si due to nitrogen based LTR application (Fire Trol 931) was studied at laboratory scale. The concentrations of Na(+), Al(3+), Fe(3+)/Fe(2+), Mn(2+), Cu(2+) and Si(4+) were measured in the resulting leachates from pots with forest soil and pine trees alone and in combination with fire. The leaching of Na, Fe and Si from treated pots was significantly greater than that from control pots. The leaching of Al, Mn and Cu was extremely low.

  8. Effect of Kaolin Clay and Alumina on Thermal Performance and Char Morphology of Intumescent fire retardant coating

    Directory of Open Access Journals (Sweden)

    aziz Hammad

    2014-07-01

    Full Text Available Intumescent fire retardant coating (IFRC have been developed by using ammonium polyphosphate, expandable graphite, melamine, boric acid, kaolin clay and alumina as fillers bound together with epoxy resin and cured with the help of curing agent. Five different formulations were developed with and without using fillers. Cured samples were burned in furnace at 500°C for 2h for char expansion. Bunsen burner test was performed for 1h using UL-94 vertical burning test to investigate the thermal performance of IFRC. The resultant char obtained after burning of coated samples were characterized by using field emission scanning electron microscopy for char morphology. Char composition was analyzed by using fourier transform infrared spectroscopy. Thermogravimetric analysis was carried out to investigate the residual weight of coating. Results showed that formulation with 0.5 weight % of kaolin clay and 0.5 weight % of alumina provide best thermal performance, uniform and multi-porous char structure with high anti-oxidation property.

  9. Silica Treatments: A Fire Retardant Strategy for Hemp Fabric/Epoxy Composites

    Directory of Open Access Journals (Sweden)

    Francesco Branda

    2016-08-01

    Full Text Available In this paper, for the first time, inexpensive waterglass solutions are exploited as a new, simple and ecofriendly chemical approach for promoting the formation of a silica-based coating on hemp fabrics, able to act as a thermal shield and to protect the latter from heat sources. Fourier Transform Infrared (FTIR and solid-state Nuclear Magnetic Resonance (NMR analysis confirm the formation of –C–O–Si– covalent bonds between the coating and the cellulosic substrate. The proposed waterglass treatment, which is resistant to washing, seems to be very effective for improving the fire behavior of hemp fabric/epoxy composites, also in combination with ammonium polyphosphate. In particular, the exploitation of hemp surface treatment and Ammonium Polyphosphate (APP addition to epoxy favors a remarkable decrease of the Heat Release Rate (HRR, Total Heat Release (THR, Total Smoke Release (TSR and Specific Extinction Area (SEA (respectively by 83%, 35%, 45% and 44% as compared to untreated hemp/epoxy composites, favoring the formation of a very stable char, as also assessed by Thermogravimetric Analysis (TGA. Because of the low interfacial adhesion between the fabrics and the epoxy matrix, the obtained composites show low strength and stiffness; however, the energy absorbed by the material is higher when using treated hemp. The presence of APP in the epoxy matrix does not affect the mechanical behavior of the composites.

  10. Effects of fire frequency on litter decomposition as mediated by changes to litter chemistry and soil environmental conditions.

    Directory of Open Access Journals (Sweden)

    Cari D Ficken

    Full Text Available Litter quality and soil environmental conditions are well-studied drivers influencing decomposition rates, but the role played by disturbance legacy, such as fire history, in mediating these drivers is not well understood. Fire history may impact decomposition directly, through changes in soil conditions that impact microbial function, or indirectly, through shifts in plant community composition and litter chemistry. Here, we compared early-stage decomposition rates across longleaf pine forest blocks managed with varying fire frequencies (annual burns, triennial burns, fire-suppression. Using a reciprocal transplant design, we examined how litter chemistry and soil characteristics independently and jointly influenced litter decomposition. We found that both litter chemistry and soil environmental conditions influenced decomposition rates, but only the former was affected by historical fire frequency. Litter from annually burned sites had higher nitrogen content than litter from triennially burned and fire suppression sites, but this was correlated with only a modest increase in decomposition rates. Soil environmental conditions had a larger impact on decomposition than litter chemistry. Across the landscape, decomposition differed more along soil moisture gradients than across fire management regimes. These findings suggest that fire frequency has a limited effect on litter decomposition in this ecosystem, and encourage extending current decomposition frameworks into disturbed systems. However, litter from different species lost different masses due to fire, suggesting that fire may impact decomposition through the preferential combustion of some litter types. Overall, our findings also emphasize the important role of spatial variability in soil environmental conditions, which may be tied to fire frequency across large spatial scales, in driving decomposition rates in this system.

  11. Effects of fire frequency on litter decomposition as mediated by changes to litter chemistry and soil environmental conditions.

    Science.gov (United States)

    Ficken, Cari D; Wright, Justin P

    2017-01-01

    Litter quality and soil environmental conditions are well-studied drivers influencing decomposition rates, but the role played by disturbance legacy, such as fire history, in mediating these drivers is not well understood. Fire history may impact decomposition directly, through changes in soil conditions that impact microbial function, or indirectly, through shifts in plant community composition and litter chemistry. Here, we compared early-stage decomposition rates across longleaf pine forest blocks managed with varying fire frequencies (annual burns, triennial burns, fire-suppression). Using a reciprocal transplant design, we examined how litter chemistry and soil characteristics independently and jointly influenced litter decomposition. We found that both litter chemistry and soil environmental conditions influenced decomposition rates, but only the former was affected by historical fire frequency. Litter from annually burned sites had higher nitrogen content than litter from triennially burned and fire suppression sites, but this was correlated with only a modest increase in decomposition rates. Soil environmental conditions had a larger impact on decomposition than litter chemistry. Across the landscape, decomposition differed more along soil moisture gradients than across fire management regimes. These findings suggest that fire frequency has a limited effect on litter decomposition in this ecosystem, and encourage extending current decomposition frameworks into disturbed systems. However, litter from different species lost different masses due to fire, suggesting that fire may impact decomposition through the preferential combustion of some litter types. Overall, our findings also emphasize the important role of spatial variability in soil environmental conditions, which may be tied to fire frequency across large spatial scales, in driving decomposition rates in this system.

  12. FRC : fire retardant clothing

    Energy Technology Data Exchange (ETDEWEB)

    Denhard, G. [Manitoba Hydro, Winnipeg, MB (Canada)

    2006-07-01

    This presentation provided details of the Manitoba Hydro's flame resistant clothing (FRC) program, which was devised after 2 separate incidents in 1998 where clothing contributed to the extent of personnel injuries. The FRC program became corporate-wide in 2005, after the utility's FRC steering committee completed an investigation of the relevant industry standards and regulatory requirements needed to develop an FRC implementation plan. Standards used to prepare the FRC policy included the standard performance specification for textile materials; the standard test method for determining arc thermal performance values of materials for clothing; the standard specification for arc and flame resistant rainwear; and the Occupational Safety and Health Administration (OSHA) 1910.269 regulation, which states that employers shall ensure that employees are not wearing clothing that could increase the extent of potential injuries. A consultation of the utility's corporate policies included the uniform, clothing and equipment policy, and the corporate safety and occupational health rule. As a result of the FRC program, Manitoba Hydro now provides personal protective clothing and equipment; flame resistant clothing; and clothing for regular exposure to certain conditions. FRC must be worn when entering energized AC or DC switchyards; operational maintenance or construction sites where a clothing ignition hazard exists; and in any area designated as requiring workers to wear FRC. The program was designed using a risk-based approach, and employees were divided into the following 4 groups: groups requiring that all layers of their clothing be FRC; groups requiring FRC as the outer layer of their clothing; groups required to wear FRC only when entering certain work sites; and special case personnel dealt with on a case-by-case basis. Implementation costs of the program were estimated at $2.3 million, with a $500,000 annual cost. However, annual costs for 2005 were $1.14 million. Implementation of the program showed that the risk assessment strategies used by the utility required more structure and that the 2000 safety rule which mandated FRC in switchyards was too restrictive. However, no injuries caused by clothing ignition have occurred. It was concluded that the structured risk hazard assessment was a key component of the program. refs., tabs., figs.

  13. EFFECTS OF IMPREGNATION WITH STYRENE AND NANO-ZINC OXIDE ON FIRE-RETARDING, PHYSICAL, AND MECHANICAL PROPERTIES OF POPLAR WOOD

    Directory of Open Access Journals (Sweden)

    Siroos Habibzade

    2016-12-01

    Full Text Available Nanoparticles have been vastly applied in wood polymer composites (WPCs in the recent years to improve some of the drawbacks of solid wood species. In the present study, the effects of ZnO nanoparticles on fire retarding, physical, and mechanical properties of polymerized poplar wood were investigated. Poplar specimens were impregnated with styrene monomer, containing four different contents of nano-zinc oxide (ZnO (0, 0.5, 1 and 1.5%, based on the dry weight of monomer. Results of the scanning electron microscopy (SEM showed homogeneous dispersion of ZnO nanoparticles in the WPC matrix. Nano-zinc oxide improved physical properties such as dimensional stability and water absorption. Moreover, mechanical properties increased in comparison to the control specimens. The impregnation process also significantly improved some of the fire-retarding properties, including the ignition time; however, the flammability nature of styrene aggravated some others, such as carbonized area. It was concluded that, although most of the properties were improved, the final application of WPC should be taken in to consideration before making decision on whether or not to impregnate populus wood with styrene.

  14. Flame Retardants Used in Flexible Polyurethane Foam

    Science.gov (United States)

    The partnership project on flame retardants in furniture seeks to update the health and environmental profiles of flame-retardant chemicals that meet fire safety standards for upholstered consumer products with polyurethane foam

  15. Joint project final report, Task II: Sulfur chemistry, Task III: Nitrogen Chemistry[Straw fired power plants

    Energy Technology Data Exchange (ETDEWEB)

    Glarborg, P.; Lans, R. van der; Weigang, L.; Arendt Jensen, P.; Degn Jensen, A.; Dam-Johansen, K.

    2001-09-01

    It is the aim of the project to promote the use of biomass in the production of power and heat in Denmark as well as enhancing the technology base of the Danish industry within this area. The project involves, the following task areas: 1) Deposit Build-up; 2) Sulfur Chemistry; 3) Nitrogen Chemistry; and 4) Furnace Modeling. The present report covers the activities in task 2 and 3, which are carried out at Department of Chemical Engineering, DTU. Task 2: Sulfur chemistry: The lab-scale results show that the amount of sulfur released into the gas-phase increases at high temperatures. Other process parameters such as oxygen concentration have less impact. Little sulfur is apparently released during char oxidation. The experiments show that about 40% of the sulfur is released during pyrolysis at 400 {sup d}eg{sup .}C. At combustion conditions it was found that about 50% of the sulfur is released at 500{sup d}eg.{sup C}; above this temperature an almost linear correlation is found beteen sulfur release and combustion temperature up to 80-85% release at 950{sup d}eg.{sup C}. The experiments are in agreement with results from full scale straw fired grate boilers, indicating that only a small amount of fuel-sulfur is fixed in the bottom ash under typical operating conditions. The results are important in order to understand the varying emission levels observed in full-scala systems and provide guidelines for low SO{sub 2} operation. Task 3: Nitrogen chemistry: In the nitgrogen chemistry submodel volatile-N is released as NH{sub 3} and N{sub 2}. The ammonia can react further to N{sub 2} or NO. Char nitrogen is oxidized to NO, and the char bed acts as a catalyst for the reduction of NO to N{sub 2}. Predictions with the bed-model including the NO submodel indicate that when all volatile nitrogen is converted to NH{sub 3}, the concentrations og NH{sub 3} are significantly overpredicted. This means that either the NH{sub 3} reaction rates are underpredicted or that a smaller

  16. Utilization of struvite recovered from high-strength ammonium-containing simulated wastewater as slow-release fertilizer and fire-retardant barrier.

    Science.gov (United States)

    Yetilmezsoy, Kaan; Kocak, Emel; Akbin, Havva Melda; Özçimen, Didem

    2018-06-28

    Sustainable uses of the struvite (magnesium ammonium phosphate hexahydrate, MgNH 4 PO 4 ·6H 2 O, MAP) recovered from the synthetic wastewater, as a high-quality slow-release fertilizer for the growth of nine medicinal plants and a fire-retardant barrier on the flammability of cotton fabric and wooden plate, were explored in this study. The previous experimental results demonstrated that under the optimal conditions, about 98.7% of [Formula: see text] (initial [Formula: see text] = 1000 mg/L) could be effectively and successfully recovered from simulated wastewater in the form of MAP precipitate. Rates of increase in total fresh weights, total dry weights, and fresh heights of plants grown in soil fertilized with the struvite were determined as 67%, 52%, and 12% for valerian; 121%, 75%, and 18% for cucumber; 421%, 260%, and 47% for dill; 314%, 318%, and 27% for coriander; 432%, 566%, and 30% for tomato; 285%, 683%, and 26% for parsley; 200%, 225%, and 9% for basil; 857%, 656%, and 92% for rocket; and 146%, 115%, and 28% for cress, respectively, compared to the control pots. The microstructure, elemental composition, surface area, thermal behaviour, and functional groups of the grown crystals were characterized using SEM, EDS, BET, TGA-DTG-DSC, and FTIR analyses, respectively. Flammability tests and thermal analyses concluded that the dried and crumbled/implanted form of struvite used as a fire-retardant barrier demonstrated a remarkable flame-resistant behaviour for both cotton fabric and wooden plate. Findings of this experimental study clearly corroborated the versatility of struvite as non-polluting and environmentally friendly clean product for the sustainable usage in different fields.

  17. Californian forest fire plumes over Southwestern British Columbia: lidar, sunphotometry, and mountaintop chemistry observations

    Directory of Open Access Journals (Sweden)

    I. McKendry

    2011-01-01

    Full Text Available Forest fires in Northern California and Oregon were responsible for two significant regional scale aerosol transport events observed in southern British Columbia during summer 2008. A combination of ground based (CORALNet and satellite (CALIPSO lidar, sunphotometry and high altitude chemistry observations permitted unprecedented characterization of forest fire plume height and mixing as well as description of optical properties and physicochemistry of the aerosol. In southwestern BC, lidar observations show the smoke to be mixed through a layer extending to 5–6 km a.g.l. where the aerosol was confined by an elevated inversion in both cases. Depolarization ratios for a trans-Pacific dust event (providing a basis for comparison and the two smoke events were consistent with observations of dust and smoke events elsewhere and permit discrimination of aerosol events in the region. Based on sunphotometry, the Aerosol Optical Thicknesses (AOT reached maxima of ~0.7 and ~0.4 for the two events respectively. Dubovik-retrieval values of reff, f during both the June/July and August events varied between about 0.13 and 0.15 μm and confirm the dominance of accumulation mode size particles in the forest fire plumes. Both Whistler Peak and Mount Bachelor Observatory data show that smoke events are accompanied by elevated CO and O3 concentrations as well as elevated K+/SO4 ratios. In addition to documenting the meteorology and physic-chemical characteristics of two regional scale biomass burning plumes, this study demonstrates the positive analytical synergies arising from the suite of measurements now in place in the Pacific Northwest, and complemented by satellite borne instruments.

  18. Using MOPITT data and a Chemistry and Transport Model to Investigate Injection Height of Plumes from Boreal Forest Fires

    Science.gov (United States)

    Hyer, E. J.; Allen, D. J.; Kasischke, E. S.; Warner, J. X.

    2003-12-01

    Trace gas emissions from boreal forest fires are a significant factor in atmospheric composition and its interannual variability. A number of recent observations of emissions plumes above individual fire events (Fromm and Servranckx, 2003; COBRA 2003; Lamarque et al., 2003; Wotawa and Trainer, 2000) suggest that vertical properties of forest fire emission plumes can be very different from fossil fuel emission plumes. Understanding and constraining the vertical properties of forest fire emission plumes and their injection into the atmosphere during fire events is critical for accurate modeling of atmospheric transport and chemistry. While excellent data have been collected in a handful of experiments on individual fire events, a systematic examination of the range of behavior observed in fire events has been hampered by the scarcity of vertical profiles of atmospheric composition. In this study, we used a high-resolution model of boreal forest fire emissions (Kasischke et al, in review) as input to the Goddard/UM CTM driven by the GEOS-3 DAS, operating at 2 by 2.5 degrees with 35 vertical levels. We modeled atmospheric injection and transport of CO emissions during the fire season of 2000 (May-September). We altered the parameters of the model to simulate a range of scenarios of plume injection, and compared the resulting output to the CO profiles from the MOPITT instrument. The results presented here pertain to the boreal forest, but our methods should be useful for atmospheric modelers hoping to more realistically model transport of emission plumes from biomass burning. References: COBRA2003: see http://www.fas.harvard.edu/~cobra/smoke_canada_030530.pdf Fromm, M. and R. Servranckx, 2003. "Stratospheric Injection of Forest Fire Emissions on August 4, 1998: A Satellite Image Analysis of the Causal Supercell Convection." Geophysical Research Abstracts 5:13118. Kasischke, E.S.; E.J. Hyer, N.H.F. French, A.I. Sukhinin, J.H. Hewson, B.J. Stocks, in review. "Carbon

  19. FIRE

    International Nuclear Information System (INIS)

    Brtis, J.S.; Hausheer, T.G.

    1990-01-01

    FIRE, a microcomputer based program to assist engineers in reviewing and documenting the fire protection impact of design changes has been developed. Acting as an electronic consultant, FIRE is designed to work with an experienced nuclear system engineer, who may not have any detailed fire protection expertise. FIRE helps the engineer to decide if a modification might adversely affect the fire protection design of the station. Since its first development, FIRE has been customized to reflect the fire protection philosophy of the Commonwealth Edison Company. That program is in early production use. This paper discusses the FIRE program in light of its being a useful application of expert system technologies in the power industry

  20. Chemical research projects office functions accomplishments programs. [applied research in the fields of polymer chemistry and polymeric composites with emphasis on fire safety

    Science.gov (United States)

    Heimbuch, A. H.; Parker, J. A.

    1975-01-01

    Basic and applied research in the fields of polymer chemistry, polymeric composites, chemical engineering, and biophysical chemistry is summarized. Emphasis is placed on fire safety and human survivability as they relate to commercial and military aircraft, high-rise buildings, mines and rapid transit transportation. Materials systems and other fire control systems developed for aerospace applications and applied to national domestic needs are described along with bench-scale and full-scale tests conducted to demonstrate the improvements in performance obtained through the utilization of these materials and fire control measures.

  1. Future fire probability modeling with climate change data and physical chemistry

    Science.gov (United States)

    Richard P. Guyette; Frank R. Thompson; Jodi Whittier; Michael C. Stambaugh; Daniel C. Dey

    2014-01-01

    Climate has a primary influence on the occurrence and rate of combustion in ecosystems with carbon-based fuels such as forests and grasslands. Society will be confronted with the effects of climate change on fire in future forests. There are, however, few quantitative appraisals of how climate will affect wildland fire in the United States. We demonstrated a method for...

  2. Elements of environmental chemistry

    National Research Council Canada - National Science Library

    Hites, R. A; Raff, Jonathan D

    2012-01-01

    ... more. Extensively revised, updated, and expanded, this second edition includes new chapters on atmospheric chemistry, climate change, and polychlorinated biphenyls and dioxins, and brominated flame retardants...

  3. Effect of ecosystem type and fire on chemistry of WEOM as measured by LDI-TOF-MS and NMR.

    Science.gov (United States)

    Crecelius, Anna C; Vitz, Jürgen; Näthe, Kerstin; Meyer, Stefanie; Michalzik, Beate; Schubert, Ulrich S

    2017-01-01

    Soil organic matter (SOM) and its water-soluble components play an important role in terrestrial carbon cycling and associated ecosystem functions. Chemically, they are complex mixtures of organic compounds derived from decomposing plant material, microbial residues, as well as root exudates, and soil biota. To test the effect of the ecosystem type (forest and grassland) and fires events on the chemistry of dissolved organic matter (DOM), we applied a combination of laser-desorption/ionization time-of-flight mass spectrometry (LDI-TOF-MS) and 2D ( 1 H and 13 C) nuclear magnetic resonance (NMR) spectroscopy to water-extractable organic matter (WEOM) from a range of top soil samples. The aim was to assess the suitability of LDI-TOF-MS for the rapid characterization of WEOM. Therefore, we evaluated the effects of sample (pH and dilution) conditions and use of positive or negative reflector mode to identify the conditions under which LDI-TOF-MS best distinguished between WEOM from different sources. Thirty-six samples were measured with both analytical techniques and their chemical patterns were statistically evaluated to distinguish firstly the effect of the type of ecosystem (forest versus grassland) on WEOM characteristics, and secondly the impact of fire on the chemical composition of WEOM. The nonmetric multidimensional scaling (NMDS) analysis of the most suitable experimental LDI-TOF-MS conditions showed a clear separation between the type of vegetation and fire-induced changes, mostly reflecting the presence of poly(ethylene glycol) in grassland soils. Discrimination among WEOM from different vegetation types was preserved in the fire treated samples. The calculation of the relative abundance of certain functional structures in the WEOM samples revealed a common composition of forest and grassland WEOM, with polysaccharides and proteins making up to 60%. The compositional impact of forest fire on WEOM was more pronounced compared to the one of grassland, leading

  4. Effects of impregnation of Eucalyptus grandis wood with fire-retardant salt on the production and quality of its charcoal; Efeito da impregnacao da madeira de Eucalyptus grandis com sais ignifugos na producao e na qualidade do carvao

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Ana Marcia Macedo Ladeira; Vital, Benedito Rocha; Gomide, Jose Livio; Della Lucia, Ricardo Marius; Leite, Helio Garcia [Vicosa Univ., MG (Brazil). Dept. de Engenharia Florestal

    1998-12-31

    The present work was carried out to investigate the effects of impregnating Eucalyptus grandis wood fire retardant salts on the production and quality of its charcoal. The wood used came from a commercial stand of 72-month old Eucalyptus grandis planted at an initial 3.0 x 2.0 m spacing, established in Vicosa, Minas Gerais, Brazil. This wood was transformed in chips, treated with some fire-retardant salts and carbonized. results were evaluated through multivariate analysis. The difference among the 34 treatments, evaluated on the wood characteristics, based on group analysis, and using the distance D{sup 2} of Mahalanobis and the Tocher method, showed distinct group and subgroup formations. Based on technological data, treatment with ammonium sulphate at 15% concentration was classified as being the most promising one. The use of canonic variables analysis showed that the treatment with ammonium sulphate at a concentration of 5% was the best, and was given preference because of its lower sulphur content. (author) 12 refs., 1 fig., 7 tabs.

  5. Wildland fire emissions, carbon, and climate: Plume rise, atmospheric transport, and chemistry processes

    Science.gov (United States)

    Warren Heilman; Yongqiang Liu; Shawn Urbanski; Vladimir Kovalev; Robert Mickler

    2014-01-01

    This paper provides an overview and summary of the current state of knowledge regarding critical atmospheric processes that affect the distribution and concentrations of greenhouse gases and aerosols emitted from wildland fires or produced through subsequent chemical reactions in the atmosphere. These critical atmospheric processes include the dynamics of plume rise,...

  6. Flame-retardant carbon nanotube films

    Science.gov (United States)

    Janas, Dawid; Rdest, Monika; Koziol, Krzysztof K. K.

    2017-07-01

    We have demonstrated fire-retardancy properties of a polymer matrix-free CNT film for the first time. As compared with classical fire-retardant materials such as Kevlar, Twaron or Nomex, the CNT film showed a spectrum of advantages. The material is lightweight, flexible and well-adherent to even the most complicated shapes. The results have showed that by using CNTs for fire-retardancy we can extend the operational time almost two-fold, what makes CNTs a much better protection than the solutions employed nowadays. We believe that among other great properties of CNT, their macroscopic assemblies such as CNT films show significant potential for becoming a fire protective coating, which exhibits high performance in not sustaining fire.

  7. Evaluation of Biogenic and Fire Emissions in a Global Chemistry Model with NOMADSS, DC3 and SEAC4RS observations

    Science.gov (United States)

    Emmons, L. K.; Wiedinmyer, C.; Park, M.; Kaser, L.; Apel, E. C.; Guenther, A. B.

    2014-12-01

    Numerous measurements of compounds produced by biogenic and fire emissions were made during several recent field campaigns in the southeast United States, providing a unique data set for emissions and chemical model evaluation. The NCAR Community Atmosphere Model with Chemistry (CAM-chem) is coupled to the Community Land Model (CLM), which includes the biogenic emissions model MEGAN-v2.1, allowing for online calculation of emissions from vegetation for 150 compounds. Simulations of CAM-chem for summers 2012 and 2013 are evaluated with the aircraft and ground-based observations from DC3, NOMADSS and SEAC4RS. Comparison of directly emitted biogenic species, such as isoprene, terpenes, methanol and acetone, are used to evaluate the MEGAN emissions. Evaluation of oxidation products, including methyl vinyl ketone (MVK), methacrolein, formaldehyde, and other oxygenated VOCs are used to test the model chemistry mechanism. In addition, several biomass burning inventories are used in the model, including FINN, QFED, and FLAMBE, and are compared for their impact on atmospheric composition and ozone production, and evaluated with the aircraft observations.

  8. Chemistry

    International Nuclear Information System (INIS)

    Ferris, L.M.

    1975-01-01

    The chemical research and development efforts related to the design and ultimate operation of molten-salt breeder reactor systems are concentrated on fuel- and coolant-salt chemistry, including the development of analytical methods for use in these systems. The chemistry of tellurium in fuel salt is being studied to help elucidate the role of this element in the intergranular cracking of Hastelloy N. Studies were continued of the effect of oxygen-containing species on the equilibrium between dissolved UF 3 and dissolved UF 4 , and, in some cases, between the dissolved uranium fluorides and graphite, and the UC 2 . Several aspects of coolant-salt chemistry are under investigation. Hydroxy and oxy compounds that could be formed in molten NaBF 4 are being synthesized and characterized. Studies of the chemistry of chromium (III) compounds in fluoroborate melts were continued as part of a systematic investigation of the corrosion of structural alloys by coolant salt. An in-line voltammetric method for determining U 4+ /U 3+ ratios in fuel salt was tested in a forced-convection loop over a six-month period. (LK)

  9. Flexible PVC flame retarded with expandable graphite

    CSIR Research Space (South Africa)

    Focke, WW

    2014-02-01

    Full Text Available this outstanding fire resistance. Thus flame-retardant (FR) and smoke-suppressant (SS) additives must be incorporated in order to meet product test specifications such as oxygen index, heat release rate, smoke evolution, or the extent of burning [1]. Levchik... plot for the composites fabricated in this work. For a material to be effectively flame retarded both the fire load and the fire growth index should assume low values. Figure 11 shows a dramatic decrease for all the EG composites relative to the neat...

  10. Fire resistant aircraft seat program

    Science.gov (United States)

    Fewell, L. A.

    1979-01-01

    Foams, textiles, and thermoformable plastics were tested to determine which materials were fire retardant, and safe for aircraft passenger seats. Seat components investigated were the decorative fabric cover, slip covers, fire blocking layer, cushion reinforcement, and the cushioning layer.

  11. Chemistry

    International Nuclear Information System (INIS)

    Ferris, L.M.

    1976-01-01

    Research progress is reported in programs on fuel-salt chemistry, properties of compounds in the Li--Te system, Te spectroscopy UF 4 --H equilibria, porous electrode studies of molten salts, fuel salt-coolant salt reactions, thermodynamic properties of transition-metal fluorides, and properties of sodium fluoroborate. Developmental work on analytical methods is summarized including in-line analysis of molten MSBR fuel, analysis of coolant-salts for tritium, analysis of molten LiF--BeF 2 --ThF 4 for Fe and analysis of LiF--BeF--ThF 4 for Te

  12. Chemistry

    International Nuclear Information System (INIS)

    Ferris, L.M.

    1975-01-01

    Research and development activities dealing with the chemical problems related to design and ultimate operation of molten-salt reactor systems are described. An experimental test stand was constructed to expose metallurgical test specimens to Te 2 vapor at defined temperatures and deposition rates. To better define the chemistry of fluoroborate coolant, several aspects are being investigated. The behavior of hydroxy and oxy compounds in molten NaBF 4 is being investigated to define reactions and compounds that may be involved in corrosion and/or could be involved in methods for trapping tritium. Two corrosion products of Hastelloy N, Na 3 CrF 6 and Na 5 Cr 3 F 14 , were identified from fluoroborate systems. The evaluation of fluoroborate and alternate coolants continued. Research on the behavior of hydrogen and its isotopes is summarized. The solubilities of hydrogen, deuterium, and helium in Li 2 BeF 4 are very low. The sorption of tritium on graphite was found to be significant (a few milligrams of tritium per kilogram of graphite), possibly providing a means of sequestering a portion of the tritium produced. Development of analytical methods continued with emphasis on voltammetric and spectrophotometric techniques for the in-line analysis of corrosion products such as Fe 2+ and Cr 3+ and the determination of the U 3+ /U 4+ ratio in MSBR fuel salt. Similar studies were conducted with the NaBF 4 --NaF coolant salt. Information developed during the previous operation of the CSTF has been assessed and used to formulate plans for evaluation of in-line analytical methods in future CSTF operations. Electroanalytical and spectrophotometric research suggests that an electroactive protonic species is present in molten NaBF 4 --NaF, and that this species rapidly equilibrates with a volatile proton-containing species. Data obtained from the CSTF indicated that tritium was concentrated in the volatile species. (JGB)

  13. Tri-(4-methoxythphenyl) phosphate: A new electrolyte additive with both fire-retardancy and overcharge protection for Li-ion batteries

    International Nuclear Information System (INIS)

    Feng, J.K.; Cao, Y.L.; Ai, X.P.; Yang, H.X.

    2008-01-01

    A novel compound, tri-(4-methoxythphenyl) phosphate, was synthesized and investigated as a safety electrolyte additive for lithium-ion batteries. It was found that this additive could lower the flammability of the electrolyte, and thereby enhance the thermal stability of the Li-ion battery. Moreover, this molecule can also be polymerized at 4.35 V (vs. Li/Li + ) to form a conducting polymer, which can protect the batteries from voltage runaway at overcharge by internal bypassing the overcharging current in the batteries. Thus, it is possible to use this electrolyte additive to provide both overcharge protection and flame retardancy for lithium-ion batteries without much influence on the battery performance

  14. Eficiência de um retardante de longa duração na redução da propagação do fogo Efficiency of a long term retardant in the reduction of fire propagation

    Directory of Open Access Journals (Sweden)

    Guido Assunção Ribeiro

    2006-12-01

    efeito de dosagens entre 900 e 1.200 mL/m², para melhorar a relação custo/benefício do uso desse produto.Non-natural firebreaks has been an alternative of wide use in forests, conservation units and at road borders to reduce fire propagation. The main objective of these firebreaks is to manage the fuel material, breaking the continuity of the fuel material. With the emergence of new products and equipment, the traditional firebreaks have being replaced by wet, green or chemical firebreaks. The objective of this work was to test the best dose of a fire retardant in a pasture area formed by Bracharia decumbens grass. Phos-chek retardant, a mixture of amonium phosphate and amonium sulphate, was used in the concentration of 0.134 kg/L. The doses were 300, 600, 900 and 1,200 ml/m². The application was carried out with a backpack pump in plots of 2 x 5 m, with four repetitions, using the complete randomized blocks design. The time spent by the fire to burn the plot without the product, time spent by the fire to burn the plot with the product, distance advanced by the fire within the plot with the product, and the burning intensity were measured. Relative moisture and wind speed were measured at one-hour intervals. The fire line took 25 times more to burn the plot with the product, in the plot with 1,200 ml/m², than the plot without the product. The fire burnt the entire plot with the 300 ml/m² dose, but the burning time in the plot with the product was larger than that one on the plot without the product. Phos-chek changes the combustion reaction, retarding the burning process and the greater the dose the greater the reaction of inhibition. The best dose was that of 1,200 ml/m², but further studies are necessary to final out the effects of doses from 900 to 1,200 ml/m², to improve the cost/benefit rate of product use.

  15. Integrating Measurement Based New Knowledge on Wildland Fire Emissions and Chemistry into the AIRPACT Air Quality Forecasting for the Pacific Northwest

    Science.gov (United States)

    Nergui, T.; Lee, Y.; Chung, S. H.; Lamb, B. K.; Yokelson, R. J.; Barsanti, K.

    2017-12-01

    A number of chamber and field measurements have shown that atmospheric organic aerosols and their precursors produced from wildfires are significantly underestimated in the emission inventories used for air quality models for various applications such as regulatory strategy development, impact assessments of air pollutants, and air quality forecasting for public health. The AIRPACT real-time air quality forecasting system consistently underestimates surface level fine particulate matter (PM2.5) concentrations in the summer at both urban and rural locations in the Pacific Northwest, primarily result of errors in organic particulate matter. In this work, we implement updated chemical speciation and emission factors based on FLAME-IV (Fourth Fire Lab at Missoula Experiment) and other measurements in the Blue-Sky fire emission model and the SMOKE emission preprocessor; and modified parameters for the secondary organic aerosol (SOA) module in CMAQ chemical transport model of the AIRPACT modeling system. Simulation results from CMAQ version 5.2 which has a better treatment for anthropogenic SOA formation (as a base case) and modified parameterization used for fire emissions and chemistry in the model (fire-soa case) are evaluated against airborne measurements downwind of the Big Windy Complex Fire and the Colockum Tarps Fire, both of which occurred in the Pacific Northwest in summer 2013. Using the observed aerosol chemical composition and mass loadings for organics, nitrate, sulfate, ammonium, and chloride from aircraft measurements during the Studies of Emissions and Atmospheric Composition, Clouds, and Climate Coupling by Regional Surveys (SEAC4RS) and the Biomass Burning Observation Project (BBOP), we assess how new knowledge gained from wildfire measurements improve model predictions for SOA and its contribution to the total mass of PM2.5 concentrations.

  16. FIRE STUDIES IN MALLEE (EUCALYPTUS SPP.) COMMUNITIES OF WESTERN NEW SOUTH WALES: SPATIAL AND TEMPORAL FLUXES IN SOIL CHEMISTRY AND SOIL BIOLOGY FOLLOWING PRESCRIBED FIRE.

    Science.gov (United States)

    The effects of prescribed fires on nutrient pools, soil-organisms, and vegetation patch dynamics were studied in three semi-arid mallee shrublands in western New South Wales. Repeated sampling of surface soil strata (0-2 and 2-4 cm) was undertaken at strategic times (immediately ...

  17. Analytical chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jae Seong

    1993-02-15

    This book is comprised of nineteen chapters, which describes introduction of analytical chemistry, experimental error and statistics, chemistry equilibrium and solubility, gravimetric analysis with mechanism of precipitation, range and calculation of the result, volume analysis on general principle, sedimentation method on types and titration curve, acid base balance, acid base titration curve, complex and firing reaction, introduction of chemical electro analysis, acid-base titration curve, electrode and potentiometry, electrolysis and conductometry, voltammetry and polarographic spectrophotometry, atomic spectrometry, solvent extraction, chromatograph and experiments.

  18. Analytical chemistry

    International Nuclear Information System (INIS)

    Choi, Jae Seong

    1993-02-01

    This book is comprised of nineteen chapters, which describes introduction of analytical chemistry, experimental error and statistics, chemistry equilibrium and solubility, gravimetric analysis with mechanism of precipitation, range and calculation of the result, volume analysis on general principle, sedimentation method on types and titration curve, acid base balance, acid base titration curve, complex and firing reaction, introduction of chemical electro analysis, acid-base titration curve, electrode and potentiometry, electrolysis and conductometry, voltammetry and polarographic spectrophotometry, atomic spectrometry, solvent extraction, chromatograph and experiments.

  19. Fundamentals of Fire Phenomena

    DEFF Research Database (Denmark)

    Quintiere, James

    analyses. Fire phenomena encompass everything about the scientific principles behind fire behaviour. Combining the principles of chemistry, physics, heat and mass transfer, and fluid dynamics necessary to understand the fundamentals of fire phenomena, this book integrates the subject into a clear...

  20. Investigating the links between ozone and organic aerosol chemistry in a biomass burning plume from a California chaparral fire

    Science.gov (United States)

    M. J. Alvarado; C. R. Lonsdale; R. J. Yokelson; S. K. Akagi; I. R. Burling; H. Coe; J. S. Craven; E. Fischer; G. R. McMeeking; J. H. Seinfeld; T. Soni; J. W. Taylor; D. R. Weise; C. E. Wold

    2014-01-01

    Within minutes after emission, rapid, complex photochemistry within a biomass burning smoke plume can cause large changes in the concentrations of ozone (O3) and organic aerosol (OA). Being able to understand and simulate this rapid chemical evolution under 5 a wide variety of conditions is a critical part of forecasting the impact of these fires...

  1. Investigating the links between ozone and organic aerosol chemistry in a biomass burning plume from a prescribed fire in California chaparral

    Science.gov (United States)

    Alvarado, M. J.; Lonsdale, C. R.; Yokelson, R. J.; Akagi, S. K.; Coe, H.; Craven, J. S.; Fischer, E. V.; McMeeking, G. R.; Seinfeld, J. H.; Soni, T.; Taylor, J. W.; Weise, D. R.; Wold, C. E.

    2015-06-01

    Within minutes after emission, complex photochemistry in biomass burning smoke plumes can cause large changes in the concentrations of ozone (O3) and organic aerosol (OA). Being able to understand and simulate this rapid chemical evolution under a wide variety of conditions is a critical part of forecasting the impact of these fires on air quality, atmospheric composition, and climate. Here we use version 2.1 of the Aerosol Simulation Program (ASP) to simulate the evolution of O3 and secondary organic aerosol (SOA) within a young biomass burning smoke plume from the Williams prescribed fire in chaparral, which was sampled over California in November 2009. We demonstrate the use of a method for simultaneously accounting for the impact of the unidentified intermediate volatility, semi-volatile, and extremely low volatility organic compounds (here collectively called "SVOCs") on the formation of OA (using the Volatility Basis Set - VBS) and O3 (using the concept of mechanistic reactivity). We show that this method can successfully simulate the observations of O3, OA, NOx, ethylene (C2H4), and OH to within measurement uncertainty using reasonable assumptions about the average chemistry of the unidentified SVOCs. These assumptions were (1) a reaction rate constant with OH of ~ 10-11 cm3 s-1; (2) a significant fraction (up to ~ 50 %) of the RO2 + NO reaction resulted in fragmentation, rather than functionalization, of the parent SVOC; (3) ~ 1.1 molecules of O3 were formed for every molecule of SVOC that reacted; (4) ~ 60 % of the OH that reacted with the unidentified non-methane organic compounds (NMOC) was regenerated as HO2; and (5) that ~ 50 % of the NO that reacted with the SVOC peroxy radicals was lost, presumably to organic nitrate formation. Additional evidence for the fragmentation pathway is provided by the observed rate of formation of acetic acid (CH3COOH), which is consistent with our assumed fragmentation rate. However, the model overestimates peroxyacetyl

  2. RESEARCH OF EFFECTIVENESS OF „PLAMOSTOP“ FIRE

    Directory of Open Access Journals (Sweden)

    Patrik MITRENGA

    2016-06-01

    Full Text Available The paper deals with testing of a water-miscible intumescent fire retardant. Experiments are conducted by thermal analysis (TG / DTG, DSC, cone calorimeter and non-standardized methods for monitoring weight loss when exposed to flame burning. Based on the experiment results and other information the most appropriate methods for testing fire retardants are reviewed. All methods by which experiments have been carried out are described. Our own method for testing fire retardants was created. It is also evaluated the effectiveness of a representative fire retardant of wood by all mentioned methods. The result of the experiment is to evaluate the suitability of each method for testing of fire retardants and evaluation fire retardant “Plamostop”.

  3. Development of flame retardant, radiation resistant insulating materials

    Energy Technology Data Exchange (ETDEWEB)

    Hagiwara, M.

    1984-01-01

    On the cables used for nuclear power stations, in particular those ranked as IE class, flame retardation test, simulated LOCA environment test, radiation resistance test and so on are imposed. The results of the evaluation of performance by these tests largely depend on the insulating materials mainly made of polymers. Ethylene propylene copolymer rubber has been widely used as cable insulator because of its electrical characteristics, workability, economy and relatively good radiation resistance, but it is combustible, therefore, in the practical use, it is necessary to make it fire resistant. The author et al. have advanced the research on the molecular design of new fire retarding materials, and successfully developed acenaphthylene bromide condensate, which is not only fire resistant but also effective for improving radiation resistance. The condition of flame retardant, radiation resistant auxiliary agents is explained, and there are additive type and reaction type in fire retarding materials. The synthesis of acenaphthylene bromide condensate and its effect of giving flame retardant and radiation resistant properties are reported. The characteristics of the cables insulated with the flame retardant ethylene propylene rubber containing acenaphthylene bromide condensate were tested, and the results are shown. (Kako, I.).

  4. An environmentally benign route for the development of compressible, thermally insulating and fire retardant aerogels through self-assembling the silk fibroin biopolymer inside the silica structure - An approach towards 3D printing of aerogels.

    Science.gov (United States)

    Maleki, Hajar; Montes, Susan; Hayati-Roodbari, Nastaran; Putz, Florian; Huesing, Nicola

    2018-06-04

    Thanks to the exceptional materials properties of silica aerogels, this fascinating highly porous material has found high performance and real-life applications in various modern industries. However, a requirement for a broadening of these applications is based on the further improvement of their properties especially with regard to mechanical strength and post-synthesis processability with minimum compromise to the other physical properties. Here, we report an entirely novel, simple and aqueous based synthesis approach to prepare mechanically robust aerogel hybrids by co-gelation of silk fibroin (SF) biopolymer, extracted from silkworm cocoons. The synthesis is based on a one-step sequential processes of acid catalysis (physical) crosslinking of the SF biopolymer and simultaneous polycondensation of tetramethyl orthosilicate (TMOS), in the presence of 5-(trimethoxysilyl)pentanoic acid (TMSPA) as a coupling agent and subsequent solvent exchange and supercritical drying. Extensive characterizations by solid-state 1H-NMR, 29Si-NMR, and 2D 1H-29Si heteronuclear correlation (HETCOR) MAS NMR spectroscopy as well as various microscopic techniques (SEM, TEM) and mechanical assessment, confirmed the molecular-level homogeneity of the hybrid nanostructure. The developed silica-SF aerogel hybrids contained an improved set of material properties, such as low density (ρb, average = 0.11 - 0.2 g cm-3), high porosity (~90%), high specific surface area (~ 400-800 m2 g-1), excellent flexibility in compression (up to 80% of strain) with three-order of magnitude improvement in the Young's modulus over that of pristine silica aerogels. In addition, the silica-SF hybrid aerogels are fire retardant and demonstrated excellent thermal insulation performance with thermal conductivities (λ) of (0.033-0.039 Wm-1 K-1). As a further advantage, the formulated hybrid silica-SF aerogel showed an excellent printability in the wet state using a micro-extrusion based 3D printing approach. The

  5. Flame Retardant Effect of Nano Fillers on Polydimethylsiloxane Composites.

    Science.gov (United States)

    Jagdale, Pravin; Salimpour, Samera; Islam, Md Hujjatul; Cuttica, Fabio; Hernandez, Francisco C Robles; Tagliaferro, Alberto; Frache, Alberto

    2018-02-01

    Polydimethylsiloxane has exceptional fire retardancy characteristics, which make it a popular polymer in flame retardancy applications. Flame retardancy of polydimethylsiloxane with different nano fillers was studied. Polydimethylsiloxane composite fire property varies because of the shape, size, density, and chemical nature of nano fillers. In house made carbon and bismuth oxide nano fillers were used in polydimethylsiloxane composite. Carbon from biochar (carbonised bamboo) and a carbon by-product (carbon soot) were selected. For comparative study of nano fillers, standard commercial multiwall carbon nano tubes (functionalised, graphitised and pristine) as nano fillers were selected. Nano fillers in polydimethylsiloxane positively affects their fire retardant properties such as total smoke release, peak heat release rate, and time to ignition. Charring and surface ceramization are the main reasons for such improvement. Nano fillers in polydimethylsiloxane may affect the thermal mobility of polymer chains, which can directly affect the time to ignition. The study concludes that the addition of pristine multiwall carbon nano tubes and bismuth oxide nano particles as filler in polydimethylsiloxane composite improves the fire retardant property.

  6. Radiation and mental retardation

    International Nuclear Information System (INIS)

    Pochin, E.E.

    1988-01-01

    A brief article discusses mental retardation in children who had been exposed to ionizing radiation in utero. The time of greatest sensitivity is between the 8th and 15th week after conception and the time of lesser sensitivity between the 16th and 25th weeks. An examination of the thresholds for exposure indicate that severe mental retardation would not result from any present environmental exposures of the public. (U.K.)

  7. Cable tray fire tests

    International Nuclear Information System (INIS)

    Klamerus, L.J.

    1978-01-01

    Funds were authorized by the Nuclear Regulatory Commission to provide data needed for confirmation of the suitability of current design standards and regulatory guides for fire protection and control in water reactor power plants. The activities of this program through August 1978 are summarized. A survey of industry to determine current design practices and a screening test to select two cable constructions which were used in small scale and full scale testing are described. Both small and full scale tests to assess the adequacy of fire retardant coatings and full scale tests on fire shields to determine their effectiveness are outlined

  8. the use of castor oil as a flame retardant in polyurethane foam

    African Journals Online (AJOL)

    Dr Abdusalam

    Flame retardant help to suppress the combustion process depending on the polymer and the fire safety test. (Desch, 1973) . Flame retarding agent either cooled, the burning material below its ignition point or exclude air by forming a blanket of inert gas. It also interferes with one or several stages of the combustion process.

  9. Flame Retardancy of Chemically Modified Lignin as Functional Additive to Epoxy Nanocomposites

    Science.gov (United States)

    John A. Howarter; Gamini P. Mendis; Alex N. Bruce; Jeffrey P. Youngblood; Mark A. Dietenberger; Laura Hasburgh

    2015-01-01

    Epoxy printed circuit boards are used in a variety of electronics applications as rigid, thermally stable substrates. Due to the propensity of components on the boards, such as batteries and interconnects, to fail and ignite the epoxy, flame retardant additives are required to minimize fire risk. Currently, industry uses brominated flame retardants, such as TBBPA, to...

  10. Intumescent paint as fire protection coating

    Directory of Open Access Journals (Sweden)

    R. B. R.S. OLIVEIRA

    Full Text Available Abstract This paper is a compendium on intumescent paint and its main features regarding chemical composition, thermophysical properties and performance as a fire-retardant material. Some of the main technical publications and lines of research on the subject are presented herein. The purpose of this paper is to show the current stage of the technical research being conducted on the topic and enable a better understanding of this fire-retardant material.

  11. Epidemiology of Mental Retardation.

    Science.gov (United States)

    Heber, Rick

    Prevalence data on mental retardation is presented including international estimates on general prevalence, age directions, geographical variations within the United States, racial and ethnic variations, economic class distributions, family variations, and population distribution in institutions. Statistics are also provided in areas of specific…

  12. Aluminum hypophosphite microencapsulated to improve its safety and application to flame retardant polyamide 6

    Energy Technology Data Exchange (ETDEWEB)

    Ge, Hua [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026 (China); Tang, Gang [School of Architecture and Civil Engineering, Anhui University of Technology, 59 Hudong Road, Ma’anshan, Anhui 243002 (China); Hu, Wei-Zhao; Wang, Bi-Bo; Pan, Ying [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026 (China); Song, Lei, E-mail: leisong@ustc.edu.cn [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026 (China); Hu, Yuan, E-mail: yuanhu@ustc.edu.cn [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026 (China); Suzhou Key Laboratory of Urban Public Safety, Suzhou Institute for Advanced Study, University of Science and Technology of China, 166 Ren’ai Road, Suzhou, Jiangsu 215123 (China)

    2015-08-30

    Highlights: • MCAHP was prepared and applied in polyamide 6. • MCA as the capsule material can improve the fire safety of AHP. • Flame retardant polyamide 6 composites with MCAHP show good flame retardancy. - Abstract: Aluminum hypophosphite (AHP) is an effective phosphorus-containing flame retardant. But AHP also has fire risk that it will decompose and release phosphine which is spontaneously flammable in air and even can form explosive mixtures with air in extreme cases. In this paper, AHP has been microencapsulated by melamine cyanurate (MCA) to prepare microencapsulated aluminum hypophosphite (MCAHP) with the aim of enhancing the fire safety in the procedure of production, storage and use. Meanwhile, MCA was a nitrogen-containing flame retardant that can work with AHP via the nitrogen-phosphorus synergistic effect to show improved flame-retardant property than other capsule materials. After microencapsulation, MCA presented as a protection layer inhibit the degradation of AHP and postpone the generation of phosphine. Furthermore, the phosphine concentration could be effectively diluted by inert decomposition products of MCA. These nonflammable decomposition products of MCA could separate phosphine from air delay the oxidizing reaction with oxygen and decrease the heat release rate, which imply that the fire safety of AHP has been improved. Furthermore, MCAHP was added into polyamide 6 to prepare flame retardant polyamide 6 composites (FR-PA6) which show good flame retardancy.

  13. Aluminum hypophosphite microencapsulated to improve its safety and application to flame retardant polyamide 6

    International Nuclear Information System (INIS)

    Ge, Hua; Tang, Gang; Hu, Wei-Zhao; Wang, Bi-Bo; Pan, Ying; Song, Lei; Hu, Yuan

    2015-01-01

    Highlights: • MCAHP was prepared and applied in polyamide 6. • MCA as the capsule material can improve the fire safety of AHP. • Flame retardant polyamide 6 composites with MCAHP show good flame retardancy. - Abstract: Aluminum hypophosphite (AHP) is an effective phosphorus-containing flame retardant. But AHP also has fire risk that it will decompose and release phosphine which is spontaneously flammable in air and even can form explosive mixtures with air in extreme cases. In this paper, AHP has been microencapsulated by melamine cyanurate (MCA) to prepare microencapsulated aluminum hypophosphite (MCAHP) with the aim of enhancing the fire safety in the procedure of production, storage and use. Meanwhile, MCA was a nitrogen-containing flame retardant that can work with AHP via the nitrogen-phosphorus synergistic effect to show improved flame-retardant property than other capsule materials. After microencapsulation, MCA presented as a protection layer inhibit the degradation of AHP and postpone the generation of phosphine. Furthermore, the phosphine concentration could be effectively diluted by inert decomposition products of MCA. These nonflammable decomposition products of MCA could separate phosphine from air delay the oxidizing reaction with oxygen and decrease the heat release rate, which imply that the fire safety of AHP has been improved. Furthermore, MCAHP was added into polyamide 6 to prepare flame retardant polyamide 6 composites (FR-PA6) which show good flame retardancy

  14. Aryl Polyphosphonates: Useful Halogen-Free Flame Retardants for Polymers

    Directory of Open Access Journals (Sweden)

    Li Chen

    2010-10-01

    Full Text Available Aryl polyphosphonates (ArPPN have been demonstrated to function in wide applications as flame retardants for different polymer materials, including thermosets, polycarbonate, polyesters and polyamides, particularly due to their satisfactory thermal stability compared to aliphatic flame retardants, and to their desirable flow behavior observed during the processing of polymeric materials. This paper provides a brief overview of the main developments in ArPPN and their derivatives for flame-retarding polymeric materials, primarily based on the authors’ research work and the literature published over the last two decades. The synthetic chemistry of these compounds is discussed along with their thermal stabilities and flame-retardant properties. The possible mechanisms of ArPPN and their derivatives containing hetero elements, which exhibit a synergistic effect with phosphorus, are also discussed.

  15. COLOUR LEARNING IN RETARDED CHILDREN*

    African Journals Online (AJOL)

    COLOUR LEARNING IN RETARDED CHILDREN* !\\'fRS E. K~SEBOOM, Principal, ADS. LEVIN, M.B., M.R.C.P., D.C.H., Hon. Medical Officer, Hamlet B School for. Retarded Children, Johannesburg. '... silly children, with no understanding .. -'. Jeremiah 4:22. Tt has been observed' that mentally retarded children have.

  16. Experimental intrauterine growth retardation.

    Science.gov (United States)

    van Marthens, E; Harel, S; Zamenshof, S

    1975-01-01

    The effects of experimental intrauterine growth retardation on subsequent fetal development, especially with respect to brain development, were studied in a new animal model. The rabbit was chosen since it has a perinatal pattern of brain development similar to that of the human. Experimental ischemia was induced during the last trimester by ligation of spiral arterioles and the differential effects on fetal development at term (30th gestational day) are reported. Specific brain regions were examined for wet weight, total cell number (DNA) and total protein content. Highly significant decreases in all these parameters were found in both the cortex and cerebellum following experimental intrauterine growth retardation; these two organs were differentially affected. The prospects and advantages of using this animal model for the study of the postnatal "catch-up growth" are discussed.

  17. Retardo mental Mental retardation

    Directory of Open Access Journals (Sweden)

    Marcio M. Vasconcelos

    2004-04-01

    Full Text Available OBJETIVO: Esta revisão aborda as recentes descobertas da neurobiologia do retardo mental, enfatizando os novos recursos da citogenética, das técnicas moleculares e da neurorradiologia para esclarecer o diagnóstico. FONTES DE DADOS: O autor pesquisou o banco de dados MEDLINE da National Library of Medicine utilizando as palavras-chave "mental retardation", "developmental disability", "child" e "adolescent" em diferentes combinações, abrangendo o período de janeiro de 2000 a outubro de 2003. Também foram utilizados os bancos de dados das revistas científicas Pediatrics e New England Journal of Medicine através da palavra-chave "mental retardation". No total, o autor consultou cerca de 1.500 títulos de artigos e 500 resumos, e teve acesso direto a 150 artigos completos pertinentes. Quando oportuno, algumas referências dos artigos consultados também foram consideradas. O site Online Mendelian Inheritance in Man foi utilizado como fonte de informações em genética clínica. SÍNTESE DOS DADOS: Em outubro de 2003, o total de síndromes genéticas associadas a retardo mental chegou a 1.149. Considerando-se o conjunto das causas genéticas ou ambientais e congênitas ou adquiridas de retardo mental, a avaliação diagnóstica atual é capaz de esclarecer a etiologia em 50 a 70% dos casos. CONCLUSÕES: O autor sugere uma avaliação diagnóstica do retardo mental em etapas lógicas, visando ao uso racional dos dispendiosos recursos da citogenética, biologia molecular e neuroimagem.OBJECTIVE: This paper describes recent advances in the neurobiology of mental retardation, emphasizing new diagnostic resources provided by cytogenetics, molecular testing, and neuroimaging. SOURCES OF DATA: MEDLINE (January 2000 through October 2003, using the following key words: mental retardation, developmental disability, child, and adolescent. Search of the Pediatrics and New England Journal of Medicine websites using the key word mental retardation. The

  18. Reduction of Fire Hazard in Materials for Irrigators and Water Collectors in Cooling Towers

    Energy Technology Data Exchange (ETDEWEB)

    Smirnov, N. V.; Konstantinova, N. I., E-mail: konstantinova-n@inbox.ru [FGBU VNIIPO of EMERCOM of Russia (All-Russian Scientific-research Institute of Fire Protection) (Russian Federation); Gordon, E. P. [Research and Production Center “Kaustik” (Russian Federation); Poedintsev, E. A. [FGBU VNIIPO of EMERCOM of Russia (All-Russian Scientific-research Institute of Fire Protection) (Russian Federation)

    2016-09-15

    A way of reducing the fire hazard of PVC film used to make cooling-tower irrigators and water collectors is examined. A new generation of fire retardant, nanostructured magnesium hydroxide, is used to impart fire retardant properties. The fabrication technology is optimized with a roller-calendering manufacturing technique, and the permissible ranges of fire hazard indicators for materials in irrigators and water collectors are determined.

  19. Turbulence-chemistry interactions in reacting flows

    Energy Technology Data Exchange (ETDEWEB)

    Barlow, R.S.; Carter, C.D. [Sandia National Laboratories, Livermore, CA (United States)

    1993-12-01

    Interactions between turbulence and chemistry in nonpremixed flames are investigated through multiscalar measurements. Simultaneous point measurements of major species, NO, OH, temperature, and mixture fraction are obtained by combining spontaneous Raman scattering, Rayleigh scattering, and laser-induced fluorescence (LIF). NO and OH fluorescence signals are converted to quantitative concentrations by applying shot-to-shot corrections for local variations of the Boltzmann fraction and collisional quenching rate. These measurements of instantaneous thermochemical states in turbulent flames provide insights into the fundamental nature of turbulence-chemistry interactions. The measurements also constitute a unique data base for evaluation and refinement of turbulent combustion models. Experimental work during the past year has focused on three areas: (1) investigation of the effects of differential molecular diffusion in turbulent combustion: (2) experiments on the effects of Halon CF{sub 3}Br, a fire retardant, on the structure of turbulent flames of CH{sub 4} and CO/H{sub 2}/N{sub 2}; and (3) experiments on NO formation in turbulent hydrogen jet flames.

  20. Retroreflective Phase Retardation Prisms.

    Science.gov (United States)

    1981-06-01

    resonant cavity of a 1.064 Mm laser. This report shows that it is possible to coat the reflecting surfaces of a porro prism so that incident plane...with controlled phase retardation can be made by coating each reflecting surface of a porro prism with a single dielectric film. The amount of phase...of angle of incidence (n, < n2) S. Phase change on reflection as a function of angle of incidence (n" n ) [RL-0202-’R 6. Porro prism 7. Phase change

  1. Development of low-smoke, flame-retarding cables

    International Nuclear Information System (INIS)

    Kato, H.; Kanemitsuya, K.; Furukawa, K.; Mio, K.

    1983-01-01

    A great deal of attention has been given to the potential fire hazard of combustion gases from organic materials. Although cable industries have developed flame-retarding organic materials for the insulation and jacketing of wires and cables, there was insufficient prevention of toxic gas formation during combustion. To cope with these problems associated with conventional PVC cables, the authors have directed to develop low-smoke, flame-retarding plasticized PVC formulations retaining the original mechanical, electrical and aging properties. A series of basic investigations on smoke suppression followed by an evaluation on practical cables could indicate some effective means to end these problems. This paper describes the results and discussion on smoke suppressing study of plasticized PVC as well as behavior and characteristics of the low-smoke, flame-retarding PVC wires and cables using these materials. (author)

  2. Radiation and mental retardation

    International Nuclear Information System (INIS)

    Pochin, E.E.

    1988-01-01

    The editorial comments on a report published by the Radiation Effects Research Foundation in Hiroshima updating information on the induction of mental changes in the light of the revised and more detailed estimate of doses of radiation during pregnancies received by those exposed at Hiroshima and Nagasaki. The estimated risks are little changed. The likelihood of a threshold for exposure during the 16th to 25th week is confirmed-at 700 mGy (with a lower 95% confidence interval of 200 mGy). For the more sensitive time between the eighth to 15th weeks a linear model with no threshold still gives a statistically adequate fit to the data. Now, however, if linear models are tested without the constraint of postulating a threshold of zero, fits are obtained indicating substantial thresholds below which mental retardation would not result. When data on all children are included the maximum likelihood threshold value averages about 250 mGy on the different criteria tested (with mean 95% confidence intervals of 0 and 550 mGy). Or if the analyses exclude five children with conditions that themselves sometimes cause mental retardation a threshold of about 400 mGy is indicated (with mean 95% confidence intervals of 150 and 600 mGy). (author)

  3. Fire Perimeters

    Data.gov (United States)

    California Natural Resource Agency — The Fire Perimeters data consists of CDF fires 300 acres and greater in size and USFS fires 10 acres and greater throughout California from 1950 to 2003. Some fires...

  4. Fire History

    Data.gov (United States)

    California Natural Resource Agency — The Fire Perimeters data consists of CDF fires 300 acres and greater in size and USFS fires 10 acres and greater throughout California from 1950 to 2002. Some fires...

  5. Fireproofing and heat insulating performance improvement of EG/ATH modified intumescent flame retardant coating treated under Co-60 radiation

    Science.gov (United States)

    Zhang, Yuehong; Luan, Weiling; Jiang, Tao

    2017-12-01

    New intumescent flame retardant (IFR) coatings with different fire retardants were prepared in this paper. Expandable graphite (EG) and Aluminium hydroxide (ATH) were respectively added into the conventional IFR coating system, which included ammonium polyphosphate (APP) / pentaerythritol (PER) / melamine (MEL). The fireproofing time and heat insulating properties of the additives acted as fire retardants were investigated via thermogravimetry analysis (TGA) and fire resistance test of homemade big panel test. The morphology of the char layer structure was achieved by scanning electron microscopy (SEM). The highlight of the paper was that the coating samples were pretreated under Co-60 radiation. The influence of radiation on the fire resistance time and char layer height was investigated. The results showed that the prepared IFR coatings can be used in Co-60 radiation for more than 90 min when encountering fire. It would be a reference for radiation shielding in nuclear environment.

  6. The Right Brain: Surviving Retardation

    Science.gov (United States)

    Science News, 1977

    1977-01-01

    Describes two studies of brain hemisphere development which indicate children retarded in the functions of one hemisphere may not be retarded in the functions of the second hemisphere. Suggests that the left hemisphere functions may inhibit some right hemisphere functions. (SL)

  7. Investigating the links between ozone and organic aerosol chemistry in a biomass burning plume from a prescribed fire in California chaparral

    Science.gov (United States)

    M.J. Alvarado; C.R. Lonsdale; R.J. Yokelson; S.K. Akagi; I.R. Burling; H. Coe; J.S. Craven; E. Fischer; G.R. McMeeking; J.H. Seinfeld; T. Soni; J.W. Taylor; D.R. Weise; C.E. Wold

    2015-01-01

    Within minutes after emission, complex photochemistry in biomass burning smoke plumes can cause large changes in the concentrations of ozone (O3) and organic aerosol (OA). Being able to understand and simulate this rapid chemical evolution under a wide variety of conditions is a critical part of forecasting the impact of these fires on air...

  8. Chemistry laboratory safety manual available

    Science.gov (United States)

    Elsbrock, R. G.

    1968-01-01

    Chemistry laboratory safety manual outlines safe practices for handling hazardous chemicals and chemistry laboratory equipment. Included are discussions of chemical hazards relating to fire, health, explosion, safety equipment and procedures for certain laboratory techniques and manipulations involving glassware, vacuum equipment, acids, bases, and volatile solvents.

  9. Radiation chemistry

    International Nuclear Information System (INIS)

    Rodgers, F.; Rodgers, M.A.

    1987-01-01

    The contents of this book include: Interaction of ionizing radiation with matter; Primary products in radiation chemistry; Theoretical aspects of radiation chemistry; Theories of the solvated electron; The radiation chemistry of gases; Radiation chemistry of colloidal aggregates; Radiation chemistry of the alkali halides; Radiation chemistry of polymers; Radiation chemistry of biopolymers; Radiation processing and sterilization; and Compound index

  10. Local Equilibrium and Retardation Revisited.

    Science.gov (United States)

    Hansen, Scott K; Vesselinov, Velimir V

    2018-01-01

    In modeling solute transport with mobile-immobile mass transfer (MIMT), it is common to use an advection-dispersion equation (ADE) with a retardation factor, or retarded ADE. This is commonly referred to as making the local equilibrium assumption (LEA). Assuming local equilibrium, Eulerian textbook treatments derive the retarded ADE, ostensibly exactly. However, other authors have presented rigorous mathematical derivations of the dispersive effect of MIMT, applicable even in the case of arbitrarily fast mass transfer. We resolve the apparent contradiction between these seemingly exact derivations by adopting a Lagrangian point of view. We show that local equilibrium constrains the expected time immobile, whereas the retarded ADE actually embeds a stronger, nonphysical, constraint: that all particles spend the same amount of every time increment immobile. Eulerian derivations of the retarded ADE thus silently commit the gambler's fallacy, leading them to ignore dispersion due to mass transfer that is correctly modeled by other approaches. We then present a particle tracking simulation illustrating how poor an approximation the retarded ADE may be, even when mobile and immobile plumes are continually near local equilibrium. We note that classic "LEA" (actually, retarded ADE validity) criteria test for insignificance of MIMT-driven dispersion relative to hydrodynamic dispersion, rather than for local equilibrium. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

  11. Pigments which reflect infrared radiation from fire

    Science.gov (United States)

    Berdahl, Paul H.

    1998-01-01

    Conventional paints transmit or absorb most of the intense infrared (IR) radiation emitted by fire, causing them to contribute to the spread of fire. The present invention comprises a fire retardant paint additive that reflects the thermal IR radiation emitted by fire in the 1 to 20 micrometer (.mu.m) wavelength range. The important spectral ranges for fire control are typically about 1 to about 8 .mu.m or, for cool smoky fires, about 2 .mu.m to about 16 .mu.m. The improved inventive coatings reflect adverse electromagnetic energy and slow the spread of fire. Specific IR reflective pigments include titanium dioxide (rutile) and red iron oxide pigments with diameters of about 1 .mu.m to about 2 .mu.m and thin leafing aluminum flake pigments.

  12. Neurotoxicity of brominated flame retardants

    Science.gov (United States)

    Polybrominated diphenyl ethers (PBDEs) have been commonly used as commercial flame retardants in a variety of products including plastics and textiles. Despite their decreasing usage worldwide, congeners continue to accumulate in the environment, including soil, dust, food, anima...

  13. An Overview of Mode of Action and Analytical Methods for Evaluation of Gas Phase Activities of Flame Retardants

    Directory of Open Access Journals (Sweden)

    Khalifah A. Salmeia

    2015-03-01

    Full Text Available The latest techniques used to prove, describe and analyze the gas phase activity of a fire retardant used in polymeric materials are briefly reviewed. Classical techniques, such as thermogravimetric analysis or microscale combustion calorimetry, as well as complex and advanced analytical techniques, such as modified microscale combustion calorimeter (MCC, molecular beam mass spectroscopy and vacuum ultra violet (VUV photoionization spectroscopy coupled with time of flight MS (TOF-MS, are described in this review. The recent advances in analytical techniques help not only in determining the gas phase activity of the flame-retardants but also identify possible reactive species responsible for gas phase flame inhibition. The complete understanding of the decomposition pathways and the flame retardant activity of a flame retardant system is essential for the development of new eco-friendly-tailored flame retardant molecules with high flame retardant efficiency.

  14. BROMINATION OF 4-VINYLCYCLOHEXANE AND APPLYING THE RESULTING PRODUCT TO IMPROVE THE FLAME RETARDANT PROPERTIES OF WOOD

    Directory of Open Access Journals (Sweden)

    N. S. Nikulina

    2014-01-01

    Full Text Available Currently, the demand for timber is increasing. Wood and products on its basis are considered to be the most popular in the construction industry, furniture industry, as building materials and other However, along with the positive features of this material there are also negative factors, which include low resistance to biological degradation, high temperature, resistance. Wood and materials based on it are the most flammable, and fire safety is characterized by the velocity of propagation of fire on the wooden structure. He is able to destroy it in a matter of minutes. So the wooden house elements must be protected from fire. It was therefore necessary for the fire protection of wood. It is in the handling of wood with flame retardants. Basic fire fighting methods is the impregnation of wood antipyrene composition, painting fire paint and constructive ways - insulation of timber, non-combustible compositions which can resist the fire. In the work of brominated 4-vinylcyclohexane formed as a by-product in the petrochemical industry, in chloroform synthesized compound with bromine 62-64 % and the possibility of using this product to get antiferromag composition. It is established that the application for the protective treatment of wood synthesized flame retardant has shown that this product can be used for the protective treatment of natural wood to make it flame retardant properties. Use as antiperiodic compositions bromodomain based products 4-vinylcyclohexane allows to obtain images of wood first group of flame retardant efficiency.

  15. Flame retardancy of highly filled polyamide 6/clay nanocomposites

    International Nuclear Information System (INIS)

    Dasari, Aravind; Yu Zhongzhen; Mai Yiuwing; Liu Songlin

    2007-01-01

    To obtain an in-depth physical knowledge of the protective barrier stability and uniformity under fire conditions, we prepared highly filled polyamide 6/organoclay nanocomposites and characterized their thermal and flammability properties. The objectives were to identify a critical composition that is needed to form a stable char with no apertures or cracks and to gain a thorough understanding of the mechanisms of flame retardancy. It was shown that there is no need for higher percentages of clay and even smaller amounts of clay (<10 wt%) should be enough to achieve good fire performance. Factors such as incoherency, poor stability and non-uniformity of the char or the presence of large cracks and formation of island-like structures were insignificant in slowing down the heat release and mass loss rates. Nevertheless, there was no stage during the flammability test where the fire completely extinguished even when the protective layer was stable and free from major cracks/apertures. Based on these results, new insights and approaches to process better flame retardant polymer nanocomposites are discussed

  16. 78 FR 17140 - Upholstered Furniture Fire Safety Technology; Meeting and Request for Comments

    Science.gov (United States)

    2013-03-20

    ... retardant (FR) chemicals, specialty fibers/fabrics without FR chemicals, inherently fire resistant materials... Furniture Fire Safety Technology; Meeting and Request for Comments AGENCY: Consumer Product Safety... Commission (CPSC, Commission, or we) is announcing its intent to hold a meeting on upholstered furniture fire...

  17. Fire Propagation Performance of Intumescent Fire Protective Coatings Using Eggshells as a Novel Biofiller

    Directory of Open Access Journals (Sweden)

    M. C. Yew

    2014-01-01

    Full Text Available This paper aims to synthesize and characterize an effective intumescent fire protective coating that incorporates eggshell powder as a novel biofiller. The performances of thermal stability, char formation, fire propagation, water resistance, and adhesion strength of coatings have been evaluated. A few intumescent flame-retardant coatings based on these three ecofriendly fire retardant additives ammonium polyphosphate phase II, pentaerythritol and melamine mixed together with flame-retardant fillers, and acrylic binder have been prepared and designed for steel. The fire performance of the coatings has conducted employing BS 476: Part 6-Fire propagation test. The foam structures of the intumescent coatings have been observed using field emission scanning electron microscopy. On exposure, the coated specimens’ B, C, and D had been certified to be Class 0 due to the fact that their fire propagation indexes were less than 12. Incorporation of ecofriendly eggshell, biofiller into formulation D led to excellent performance in fire stopping (index value, (I=4.3 and antioxidation of intumescent coating. The coating is also found to be quite effective in water repellency, uniform foam structure, and adhesion strength.

  18. Synthesis and Application of a Novel Polyamide Charring Agent for Halogen-Free Flame Retardant Polypropylene

    Directory of Open Access Journals (Sweden)

    Jie Liu

    2013-01-01

    Full Text Available A novel charring agent, poly(p-ethylene terephthalamide (PETA, for halogen-free flame retardant polypropylene was synthesized by using p-phthaloyl chloride (TPC and ethylenediamine through solution polycondensation at low temperature, and the effects of PETA on flame retardance of polypropylene (PP/IFR systems were studied. The experimental results showed that PETA could considerably enhance the fire retardant performance as proved by evidence of the increase of limiting oxygen index (LOI values, the results of UL-94 tests, and cone calorimeter tests (CCT. Fourier transform infrared spectroscopy (FTIR and scanning electron microscope (SEM demonstrated that an appropriate amount of PETA could react with PP/IFR system to form cross-link network; a more compact char layer could be formed which was responsible for the improved thermal and flame retardant properties of PP/IFR systems. However, the superfluous amount of PETA would play the negative role.

  19. Development of halogen-free flame-retardant cable for nuclear power plant

    International Nuclear Information System (INIS)

    Ishii, Nobuhisa; Morii, Akira; Fujimura, Shunichi

    1991-01-01

    Conventional flame-retardant cables release a large amount of corrosive and toxic gases and also smoke during combustion on fire. Cables covered with halogen-free flame-retardant material, containing no halogen in it, have been developed to reduce generation of such gases and smoke, and already used in telecommunication plant, subway and shipboard applications. In the case of nuclear power plant application, cable covering materials should also have radiation resistance and other properties including long-term physical stability. We have developed halogen-free flame-retardant cables for nuclear power plant with sufficient flame retardancy, radiation resistance, and environmental resistance including steam-exposure resistance, all of which are in accordance with Japanese specifications for nuclear cables, and with characteristics as low corrosiveness, low toxicity, and low smoke evolution. (author)

  20. Fire protection

    International Nuclear Information System (INIS)

    Janetzky, E.

    1980-01-01

    Safety and fire prevention measurements have to be treated like the activities developing, planning, construction and erection. Therefore it is necessary that these measurements have to be integrated into the activities mentioned above at an early stage in order to guarantee their effectiveness. With regard to fire accidents the statistics of the insurance companies concerned show that the damage caused increased in the last years mainly due to high concentration of material. Organization of fire prevention and fire fighting, reasons of fire break out, characteristics and behaviour of fire, smoke and fire detection, smoke and heat venting, fire extinguishers (portable and stationary), construction material in presence of fire, respiratory protection etc. will be discussed. (orig./RW)

  1. Research on flame retardation of wool fibers

    International Nuclear Information System (INIS)

    Enomoto, Ichiro; Ametani, Kazuo; Sawai, Takeshi

    1990-01-01

    Flame retardant, vinyl phosphonate oligomer, was uniformly impregnated in wool fibers, and by irradiating low energy electron beam or cobalt-60 gamma ray, the flame retardation of fabrics was attempted, as the results, the following knowledges were obtained. At the rate of sticking of flame retardant lower than that in cotton fabrics, sufficient flame retarding property can be given. The flame retarding property withstands 30 times of washing. The lowering of strength due to the processing hardly arose. For the flame retardation, gamma-ray was more effective than electron beam. Since the accidents of burning clothes have occurred frequently, their flame retardation has been demanded. So far the flame retardation of cotton fabrics has been advanced, but this time the research on the flame retardation of wool fabrics was carried out by the same method. The experimental method is explained. As for the performance of the processed fabrics, the rate of sticking of the flame retardant, the efficiency of utilization, the flame retarding property, the endurance in washing and the tensile and tearing strength were examined. As the oxygen index was higher, the flame retarding property was higher, and in the case of the index being more than 27, the flame retarding property is sufficient, that is, the rate of sticking of 6% in serge and 5% in muslin. (K.I.)

  2. Bad chemistry

    OpenAIRE

    Petsko, Gregory A

    2004-01-01

    General chemistry courses haven't changed significantly in forty years. Because most basic chemistry students are premedical students, medical schools have enormous influence and could help us start all over again to create undergraduate chemistry education that works.

  3. Emission and chemistry of organic compounds from biomass burning: measurements from an iodide time-of-flight chemical ionization mass spectrometer (I- ToF-CIMS) during the FIREX FireLab 2016 intensive

    Science.gov (United States)

    Yuan, B.; Krechmer, J. E.; Warneke, C.; Coggon, M.; Koss, A.; Lim, C. Y.; Selimovic, V.; Gilman, J.; Lerner, B. M.; Stark, H.; Kang, H.; Jimenez, J. L.; Yokelson, R. J.; Liggio, J.; Roberts, J. M.; Kroll, J. H.; De Gouw, J. A.

    2017-12-01

    Biomass burning can emit large amounts of many different organic compounds to the atmosphere. The emission strengths of these emitted organic compounds and their subsequent atmospheric chemistry are not well known. In this study, we deployed a time-of-flight chemical ionization mass spectrometer using iodide as reagent ions (Iodide ToF-CIMS) to measure direct emissions of organic compounds during the FIREX laboratory 2016 intensive in the USDA Fire Sciences Lab in Missoula, MT. An interpretation of the I­- TOF-CIMS mass spectra from biomass burning emissions will be presented. The dependence of the emissions of selected organic compounds with fuel types, combustion efficiency and fuel chemical compositions will be discussed. The I- TOF-CIMS also measured aged biomass burning smoke from a small smog chamber and an oxidative flow reactor (OFR). The I- TOF-CIMS consistently observed much higher signals of highly oxygenated organic compounds in the aged biomass burning smoke than in fresh emissions, indicative of strong secondary formation of these organic compounds in biomass burning plumes.

  4. Determination of antimony trioxide in fire-retardant conveyor belts

    Energy Technology Data Exchange (ETDEWEB)

    Rytych-Witwicka, B.; Szmyd, E.

    1976-12-01

    Two methods for the determination of antimony trioxide in rubber and pvc are described. One is a colorimetric method based on the reaction of antimony with rhodamine B; the other is a polarographic method. The results of the two methods show a satisfactory consistency and the methods themselves appear rapid and effective.

  5. Cone calorimeter study of polyethylene flame retarded with expandable graphite and intumescent fire-retardant additives

    CSIR Research Space (South Africa)

    Kruger, HR

    2014-10-01

    Full Text Available stream_source_info Ofosu2_2014_ABSTRACT.pdf.txt stream_content_type text/plain stream_size 1510 Content-Encoding ISO-8859-1 stream_name Ofosu2_2014_ABSTRACT.pdf.txt Content-Type text/plain; charset=ISO-8859-1 Journal...

  6. Genetic Counseling in Mental Retardation.

    Science.gov (United States)

    Bowen, Peter

    The task of the genetic counselor who identifies genetic causes of mental retardation and assists families to understand risk of recurrence is described. Considered are chromosomal genetic disorders such as Down's syndrome, inherited disorders such as Tay-Sachs disease, identification by testing the amniotic fluid cells (amniocentresis) in time…

  7. Epilepsy and Comorbid Mental Retardation

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2007-08-01

    Full Text Available Preventable and unpreventable causes of childhood-onset epilepsy associated with mental retardation were determined in 692 patients with epilepsy onset between 1977 and 1985 in a Nova Scotia population-based cohort studied in the Department of Pediatrics, Dalhousie University, Halifax, Canada.

  8. Mental Retardation: Diagnosis and Treatment.

    Science.gov (United States)

    Poser, Charles M., Ed.

    A collection of writings by 17 authors, the text includes the following discussions: general principles of diagnosis and management of mental retardation, neurologic evaluation of the infant and child, psychological evaluation, educational information, and treatment of pseudoretardation, communicative disorders, and metabolic and endocrine causes.…

  9. Boerhaave on Fire

    Science.gov (United States)

    Diemente, Damon

    2000-01-01

    In 1741 an English translation of Herman Boerhaave's celebrated textbook Elementa Chemic was published under the title A New Method of Chemistry. True to its time, this book included elaborate discussions of the elements earth, water, air, and fire. This article offers to teachers for classroom use a selection of passages from Boerhaave's chapter on fire. Now, today's teacher of chemistry is apt to feel that little of significance to the modern classroom can be gleaned from a two-and-a-half-centuries-old text, and especially from a topic as old-fashioned as fire. But this view is decidedly shortsighted. Boerhaave offers demonstrations and experiments that can be instructively performed today, quantitative data that can be checked against modern equations, and much theory and hypothesis that can be assessed in light of modern chemical ideas. In the readings presented here I have found material for discussion in class, for investigation in the laboratory, and for a few homework assignments. Modern students are well able to comprehend and paraphrase Boerhaave, to check his results, appreciate his insights, and identify his shortfalls. From him they learn firsthand how painstaking and difficult it was to imagine and develop the concepts of thermochemistry. To read from his chapter on fire is to stand witness to the birth and infancy of thermodynamics as conceived in the mind of a great chemist from the age when coherent chemical theory was just beginning to emerge.

  10. Mental Retardation and Parenting Stress

    Directory of Open Access Journals (Sweden)

    Eleni Siamaga

    2011-01-01

    Full Text Available Backround: The presence, upbringing and looking after of a mentally retarded child in the family, can become a threat to the mental health of its parents and is the main predisposing factor of stress for the parents.Aim: The purpose of this systematic review is (a to document the contemporary research bibliography related to the stress of parents with mentally retarded children, (b to aggregate the factors and secondary parameters based on the contemporary research related to the influence of the (child’s mental retardation on the parents and (c to show an intercultural aspect regarding the presence of stress to parents with mentally retarded children.Methods: Systematic review of research articles published in scientific journals included in the international academic databases HEAL-LING, SAGE, ELSEVIER, WILSON, SCIENCEDIRECT, MEDLINE, PUBMED, PsycINFO, Cochrane, EMBASE, SCIRUS and CINAHL having as search criteria and key words the terms («parental stress and mental retardation» [MeSH], «parenting stress and persons with special needs» [MeSH], «mental retardation and family problems» [MeSH], «stress and parents» [MeSH], «parenting and stress» [MeSH], «mental delay and parents» [MeSH], «developmental disabilities and family stress» [MeSH], «intellectual handicap and parenting» [MeSH], «maternal stress and child with disabilities» [MeSH].Discussion: The review has proven that all forms of mental retardation have an important -from a statistic point of viewimpacton the parents’ mental health. Anxiety, stress and depression are common symptoms mentioned by the parents.Additionally, there are individual variables such as the husband-wife relationship, the parents’ approach to their child’s disability, the parental strategies used in order to cope with the daily life of the child’s disability and the behavioural problems of their child, all of which contribute to the increase of the level of parental stress

  11. Mental retardation and prenatal methylmercury toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Trasande, L.; Schechter, C.B.; Haynes, K.A.; Landrigan, P.J. [CUNY Mt. Sinai School of Medicine, New York, NY (United States). Dept. of Community & Preventative Medicine

    2006-03-15

    Methylmercury (MeHg) is a developmental neurotoxicant; exposure results principally from consumption of seafood contaminated by mercury (Hg). In this analysis, the burden of mental retardation (MR) associated with methylmercury exposure in the 2000 U.S. birth cohort is estimated, and the portion of this burden attributable to mercury (Hg) emissions from coal-fired power plants is identified. The aggregate loss in cognition associated with MeHg exposure in the 2000 U.S. birth cohort was estimated using two previously published dose-response models that relate increases in cord blood Hg concentrations with decrements in IQ. MeHg exposure was assumed not to be correlated with native cognitive ability. Previously published estimates were used to estimate economic costs of MR caused by MeHg. Downward shifts in IQ resulting from prenatal exposure to MeHg of anthropogenic origin are associated with 1,566 excess cases of MR annually (range: 376-14,293). This represents 3.2% of MR cases in the US (range: 0.8%-29.2%). The MR costs associated with decreases in IQ in these children amount to $2.0 billion/year (range: $0.5-17.9 billion). Hg from American power plants accounts for 231 of the excess MR cases year (range: 28-2,109), or 0.5% (range: 0.06%-4.3%) of all MR. These cases cost $289 million (range: $35 million-2.6 billion). Toxic injury to the fetal brain caused by Hg emitted from coal-fired power plants exacts a significant human and economic toll on American children.

  12. People with Mental Retardation Are Dying, Legally.

    Science.gov (United States)

    Keyes, Denis; And Others

    1997-01-01

    Criticizes the institution of the death penalty for convicted criminals with mental retardation. Examples are given of cases in which juries were not told of the defendant's mental retardation before sentencing, and a list of defendants with mental retardation that have been executed since 1976 is provided. (CR)

  13. Fire Stations

    Data.gov (United States)

    Department of Homeland Security — Fire Stations in the United States Any location where fire fighters are stationed or based out of, or where equipment that such personnel use in carrying out their...

  14. Adsorber fires

    International Nuclear Information System (INIS)

    Holmes, W.

    1987-01-01

    The following conclusions are offered with respect to activated charcoal filter systems in nuclear power plants: (1) The use of activated charcoal in nuclear facilities presents a potential for deep-seated fires. (2) The defense-in-depth approach to nuclear fire safety requires that if an ignition should occur, fires must be detected quickly and subsequently suppressed. (3) Deep-seated fires in charcoal beds are difficult to extinguish. (4) Automatic water sprays can be used to extinguish fires rapidly and reliably when properly introduced into the burning medium. The second part of the conclusions offered are more like challenges: (1) The problem associated with inadvertent actuations of fire protection systems is not a major one, and it can be reduced further by proper design review, installation, testing, and maintenance. Eliminating automatic fire extinguishing systems for the protection of charcoal adsorbers is not justified. (2) Removal of automatic fire protection systems due to fear of inadvertent fire protection system operation is a case of treating the effect rather than the cause. On the other hand, properly maintaining automatic fire protection systems will preserve the risk of fire loss at acceptable levels while at the same time reducing the risk of damage presented by inadvertent operation of fire protection systems

  15. Influence of Flame Retardants on the Melt Dripping Behaviour of Thermoplastic Polymers

    Directory of Open Access Journals (Sweden)

    Melissa Matzen

    2015-08-01

    Full Text Available Melt flow and dripping of the pyrolysing polymer melt can be both a benefit and a detriment during a fire. In several small-scale fire tests addressing the ignition of a defined specimen with a small ignition source, well-adjusted melt flow and dripping are usually beneficial to pass the test. The presence of flame retardants often changes the melt viscosity crucially. The influence of certain flame retardants on the dripping behaviour of four commercial polymers, poly(butylene terephthalate (PBT, polypropylene (PP, polypropylene modified with ethylene-propylene rubber (PP-EP and polyamide 6 (PA 6, is analysed based on an experimental monitoring of the mass loss due to melt dripping, drop size and drop temperature as a function of the furnace temperature applied to a rod-shaped specimen. Investigating the thermal transition (DSC, thermal and thermo-oxidative decomposition, as well as the viscosity of the polymer and collected drops completes the investigation. Different mechanisms of the flame retardants are associated with their influence on the dripping behaviour in the UL 94 test. Reduction in decomposition temperature and changed viscosity play a major role. A flow limit in flame-retarded PBT, enhanced decomposition of flame-retarded PP and PP-EP and the promotion of dripping in PA 6 are the salient features discussed.

  16. Fire performance of multi-storey wooden facades

    Directory of Open Access Journals (Sweden)

    Östman Birgit A.-L.

    2013-11-01

    Full Text Available Two series of full scale fire tests of wooden facades according to the Swedish test SP Fire 105 are presented, one series for different shares of untreated wood (partial wood and structural fire protection with a fire shield above the window and another series for fire retardant treated, FRT, wood. The results are compared with data from the Single Burning Item test and the cone calorimeter. For FRT wood, the need for verification of the weather durability of the treatment is stressed and a new European technical specification CEN/TS 15912 presented. The need to use fire stops behind multi-storey façade claddings to avoid fire spread in the cavities is underlined and the possibilities of fire safety design with sprinklers is briefly presented.

  17. Complex chemistry

    International Nuclear Information System (INIS)

    Kim, Bong Gon; Kim, Jae Sang; Kim, Jin Eun; Lee, Boo Yeon

    2006-06-01

    This book introduces complex chemistry with ten chapters, which include development of complex chemistry on history coordination theory and Warner's coordination theory and new development of complex chemistry, nomenclature on complex with conception and define, chemical formula on coordination compound, symbol of stereochemistry, stereo structure and isomerism, electron structure and bond theory on complex, structure of complex like NMR and XAFS, balance and reaction on solution, an organo-metallic chemistry, biology inorganic chemistry, material chemistry of complex, design of complex and calculation chemistry.

  18. US Fire Administration Fire Statistics

    Data.gov (United States)

    Department of Homeland Security — The U.S. Fire Administration collects data from a variety of sources to provide information and analyses on the status and scope of the fire problem in the United...

  19. Mathematical Chemistry

    OpenAIRE

    Trinajstić, Nenad; Gutman, Ivan

    2002-01-01

    A brief description is given of the historical development of mathematics and chemistry. A path leading to the meeting of these two sciences is described. An attempt is made to define mathematical chemistry, and journals containing the term mathematical chemistry in their titles are noted. In conclusion, the statement is made that although chemistry is an experimental science aimed at preparing new compounds and materials, mathematics is very useful in chemistry, among other things, to produc...

  20. Parental Attitude Towards Mental Retardation

    Directory of Open Access Journals (Sweden)

    LEOKADIA WIATROWSKA

    2017-10-01

    Full Text Available https://doaj.org/puChild's developmental retardation is an undoubted condition for the absence of educational attainment and its unpleasant mental state. Due to the nature of multidimensional state of that, parental attitudes become relevant, as they affect the acceleration or retardation of development. Positive parental attitudes are the strong weapon for the child and his struggles on the way to an equal start and equal development opportunities. For this reason you should emphasize those factors that build the structures supporting developmental progression.An ecosystem approach to human development emphasizes each factor as relevant component for growth and expansion, without denying its own human activity and his self-determination rightblisher/metadata

  1. Forest fires

    International Nuclear Information System (INIS)

    Fuller, M.

    1991-01-01

    This book examines the many complex and sensitive issues relating to wildland fires. Beginning with an overview of the fires of 1980s, the book discusses the implications of continued drought and considers the behavior of wildland fires, from ignition and spread to spotting and firestorms. Topics include the effects of weather, forest fuels, fire ecology, and the effects of fire on plants and animals. In addition, the book examines firefighting methods and equipment, including new minimum impact techniques and compressed air foam; prescribed burning; and steps that can be taken to protect individuals and human structures. A history of forest fire policies in the U.S. and a discussion of solutions to fire problems around the world completes the coverage. With one percent of the earth's surface burning every year in the last decade, this is a penetrating book on a subject of undeniable importance

  2. Forest fires in Pennsylvania.

    Science.gov (United States)

    Donald A. Haines; William A. Main; Eugene F. McNamara

    1978-01-01

    Describes factors that contribute to forest fires in Pennsylvania. Includes an analysis of basic statistics; distribution of fires during normal, drought, and wet years; fire cause, fire activity by day-of-week; multiple-fire day; and fire climatology.

  3. FIRE RESISTANCE OF DOUGLAS FIR [Pseudotsuga menziesii (Mirb. Franco] WOOD TREATED WITH SOME CHEMICALS

    Directory of Open Access Journals (Sweden)

    M. Kemal YALINKILIÇ

    1998-02-01

    Full Text Available Combustible properties of treated douglas wood specimens and fire-retardancy of some preservatives were tested in this study. Crib test of ASTM E 160-150 was followed. Results indicated that, aqueous solutions of boric acid (BA, borax (Bx (Na2BO7 10H2O or BA + Bx mixture (7: 3, w: w had fire retardant efficacy (FRE over untreated wood and reduced the combustibility of vinil monomers (Styrene and methylmetacrylate which were applied as secondary treatment.

  4. Exploring the Modes of Action of Phosphorus-Based Flame Retardants in Polymeric Systems

    Directory of Open Access Journals (Sweden)

    Sebastian Rabe

    2017-04-01

    Full Text Available Phosphorus-based flame retardants were incorporated into different, easily preparable matrices, such as polymeric thermoset resins and paraffin as a proposed model for polyolefins and investigated for their flame retardancy performance. The favored mode of action of each flame retardant was identified in each respective system and at each respective concentration. Thermogravimetric analysis was used in combination with infrared spectroscopy of the evolved gas to determine the pyrolysis behavior, residue formation and the release of phosphorus species. Forced flaming tests in the cone calorimeter provided insight into burning behavior and macroscopic residue effects. The results were put into relation to the phosphorus content to reveal correlations between phosphorus concentration in the gas phase and flame inhibition performance, as well as phosphorus concentration in the residue and condensed phase activity. Total heat evolved (fire load and peak heat release rate were calculated based on changes in the effective heat of combustion and residue, and then compared with the measured values to address the modes of action of the flame retardants quantitatively. The quantification of flame inhibition, charring, and the protective layer effect measure the non-linear flame retardancy effects as functions of the phosphorus concentration. Overall, this screening approach using easily preparable polymer systems provides great insight into the effect of phosphorus in different flame retarded polymers, with regard to polymer structure, phosphorus concentration, and phosphorus species.

  5. 46 CFR 28.820 - Fire pumps, fire mains, fire hydrants, and fire hoses.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Fire pumps, fire mains, fire hydrants, and fire hoses... REQUIREMENTS FOR COMMERCIAL FISHING INDUSTRY VESSELS Aleutian Trade Act Vessels § 28.820 Fire pumps, fire mains, fire hydrants, and fire hoses. (a) Each vessel must be equipped with a self-priming, power driven fire...

  6. Wildland fire limits subsequent fire occurrence

    Science.gov (United States)

    Sean A. Parks; Carol Miller; Lisa M. Holsinger; Scott Baggett; Benjamin J. Bird

    2016-01-01

    Several aspects of wildland fire are moderated by site- and landscape-level vegetation changes caused by previous fire, thereby creating a dynamic where one fire exerts a regulatory control on subsequent fire. For example, wildland fire has been shown to regulate the size and severity of subsequent fire. However, wildland fire has the potential to influence...

  7. Chemistry Notes

    Science.gov (United States)

    School Science Review, 1976

    1976-01-01

    Described are eight chemistry experiments and demonstrations applicable to introductory chemistry courses. Activities include: measure of lattice enthalpy, Le Chatelier's principle, decarboxylation of soap, use of pocket calculators in pH measurement, and making nylon. (SL)

  8. Chemistry Dashboard

    Science.gov (United States)

    The Chemistry Dashboard is part of a suite of dashboards developed by EPA to help evaluate the safety of chemicals. The Chemistry Dashboard provides access to a variety of information on over 700,000 chemicals currently in use.

  9. New Agents for the Extinguishment of Magnesium Fires.

    Science.gov (United States)

    1978-04-01

    34 23 July 1942. German Patent 724,795. 8. Beythien, R., Wienhaus, H., and von Zehman, H., "Extinguish- ing Magnesium and Other Light Metal Fires ," 12...34Trimethoxyboroxine--An Extinguishing Agent for Metal Fires ," ACS Advances in Chemistry, No. 23, American Chemical Society, Washington, D.C. pp 158...13. Miyashima, Z., "Fire Extinguishing Agent," 7 October 1958. Japanese Patent 8,946. 14. Jenkner, H., "Extinguishing Metal Fires ," 12 September

  10. Combinatorial chemistry

    DEFF Research Database (Denmark)

    Nielsen, John

    1994-01-01

    An overview of combinatorial chemistry is presented. Combinatorial chemistry, sometimes referred to as `irrational drug design,' involves the generation of molecular diversity. The resulting chemical library is then screened for biologically active compounds.......An overview of combinatorial chemistry is presented. Combinatorial chemistry, sometimes referred to as `irrational drug design,' involves the generation of molecular diversity. The resulting chemical library is then screened for biologically active compounds....

  11. Aquatic Chemistry

    International Nuclear Information System (INIS)

    Kim, Dong Yeun; Kim, Oh Sik; Kim, Chang Guk; Park, Cheong Gil; Lee, Gwi Hyeon; Lee, Cheol Hui

    1987-07-01

    This book deals aquatic chemistry, which treats water and environment, chemical kinetics, chemical balance like dynamical characteristic, and thermodynamics, acid-base chemistry such as summary, definition, kinetics, and PH design for mixture of acid-base chemistry, complex chemistry with definition, and kinetics, precipitation and dissolution on summary, kinetics of precipitation and dissolution, and balance design oxidation and resolution with summary, balance of oxidation and resolution.

  12. Positronium chemistry

    CERN Document Server

    Green, James

    1964-01-01

    Positronium Chemistry focuses on the methodologies, reactions, processes, and transformations involved in positronium chemistry. The publication first offers information on positrons and positronium and experimental methods, including mesonic atoms, angular correlation measurements, annihilation spectra, and statistical errors in delayed coincidence measurements. The text then ponders on positrons in gases and solids. The manuscript takes a look at the theoretical chemistry of positronium and positronium chemistry in gases. Topics include quenching, annihilation spectrum, delayed coincidence

  13. Environment-friendly, flame retardant thermoplastic elastomer-magnesium hydroxide composites

    Science.gov (United States)

    Tang, Hao; Chen, Kunfeng; Li, Xiaonan; Ao, Man; Guo, Xinwen; Xue, Dongfeng

    Halogen-free and environment-friendly magnesium hydroxide (Mg(OH)2) was synthesized to enhance the flame retardant properties of thermoplastic elastomer (TPE). When the Mg(OH)2 content was optimized to 35wt.%, the TPE-Mg(OH)2 composites exhibited the best flame retardant properties. The results showed that there was a delay of ignition time of the samples containing Mg(OH)2; compared with the samples without Mg(OH)2, the heat release rate and total heat release decrease by 31.4% and 35.6%, while total smoke production and mass loss rate reduce by 56% and 34.2%, respectively. This work opens a door to manufacture fire-resistant polymer-based composites with environmental-friendly flame retardant additives by controllable crystallization and chemical strategies.

  14. Forensic Chemistry

    Science.gov (United States)

    Bell, Suzanne

    2009-07-01

    Forensic chemistry is unique among chemical sciences in that its research, practice, and presentation must meet the needs of both the scientific and the legal communities. As such, forensic chemistry research is applied and derivative by nature and design, and it emphasizes metrology (the science of measurement) and validation. Forensic chemistry has moved away from its analytical roots and is incorporating a broader spectrum of chemical sciences. Existing forensic practices are being revisited as the purview of forensic chemistry extends outward from drug analysis and toxicology into such diverse areas as combustion chemistry, materials science, and pattern evidence.

  15. On fire

    DEFF Research Database (Denmark)

    Hansen, Helle Rabøl

    The title of this paper: “On fire”, refers to two (maybe three) aspects: firstly as a metaphor of having engagement in a community of practice according to Lave & Wenger (1991), and secondly it refers to the concrete element “fire” in the work of the fire fighters – and thirdly fire as a signifier...

  16. Fire Power

    Science.gov (United States)

    Denker, Deb; West, Lee

    2009-01-01

    For education administrators, campus fires are not only a distressing loss, but also a stark reminder that a campus faces risks that require special vigilance. In many ways, campuses resemble small communities, with areas for living, working and relaxing. A residence hall fire may raise the specter of careless youth, often with the complication of…

  17. 46 CFR 28.315 - Fire pumps, fire mains, fire hydrants, and fire hoses.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Fire pumps, fire mains, fire hydrants, and fire hoses... After September 15, 1991, and That Operate With More Than 16 Individuals on Board § 28.315 Fire pumps, fire mains, fire hydrants, and fire hoses. (a) Each vessel 36 feet (11.8 meters) or more in length must...

  18. Forest-fire models

    Science.gov (United States)

    Haiganoush Preisler; Alan Ager

    2013-01-01

    For applied mathematicians forest fire models refer mainly to a non-linear dynamic system often used to simulate spread of fire. For forest managers forest fire models may pertain to any of the three phases of fire management: prefire planning (fire risk models), fire suppression (fire behavior models), and postfire evaluation (fire effects and economic models). In...

  19. Mental Retardation; Its Social Context and Social Consequences.

    Science.gov (United States)

    Farber, Bernard

    Concerned with mental retardation as a social product, the following topics are discussed: mental retardation as a social phenomenon, the concept of the retarded as surplus population, labeling and incompetence in relation to life chances, mental retardation as deviance and as incompetence, and findings on the prevalence of retardation in the…

  20. Radiation-grafting of flame retardants on flax fabrics - A comparison between different flame retardant structures

    Science.gov (United States)

    Teixeira, Marie; Sonnier, Rodolphe; Otazaghine, Belkacem; Ferry, Laurent; Aubert, Mélanie; Tirri, Teija; Wilén, Carl-Eric; Rouif, Sophie

    2018-04-01

    Three unsaturated compounds bearing respectively phosphate, aryl bromide and sulfenamide moieties were used as flame retardants (FR) for flax fabrics. Due to the presence of carbon-carbon double bonds, radiation-grafting was considered to covalently bond these FR onto fiber structure. Grafting efficiency and location of FR molecules were investigated by weight measurements and SEM-EDX observations. Flammability and especially self-extinguishment were assessed by thermogravimetric analysis, pyrolysis-combustion flow calorimetry and a non-standardized fire test already used in previous studies. All FRs were able to diffuse into elementary fiber bulk. Nevertheless only the phosphonated monomer (noted FR-P) was significantly grafted onto flax. Self-extinguishment was obtained for fabrics containing at least around 0.5 wt% of phosphorus. On the contrary the FR content of flax fibers after radiation-grafting procedure and washing was negligible for FR-S and FR-Br, evidencing that these molecules have not been grafted upon irradiation. Moreover, the combination of these molecules prevents the radiation-grafting of other molecules which showed good grafting rate when used alone.

  1. Novel routes in flame retardancy of bisphenol A polycarbonate/impact modifier/aryl phosphate blends

    Energy Technology Data Exchange (ETDEWEB)

    Wawrzyn, Eliza

    2013-07-01

    The massive use of electronic engineering products accompanied by high demands on fire safety has led to increasing interest in environmentally friendly flame retardancy of bisphenol A polycarbonate (PC) based materials. In this work, novel routes for enhancing the flame retardancy of PC/Impact Modifier/Aryl phosphate were studied with respect to pyrolysis (TG, TG-FTIR, ATR-FTIR, NMR), flammability (LOI and UL 94) and fire behavior (cone calorimeter at different irradiations). To improve charring of PC/ABS{sub PTFE}+Aryl phosphate, the exchange of bisphenol A bis(diphenyl phosphate) (BDP) with novel aryl phosphates was proposed. Two novel flame retardants were synthesized: 3,3,5-trimethylcyclohexylbisphenol-bis(diphenyl phosphate) (TMC-BDP) and bisphenol A-bis(diethylphosphate) (BEP). TMC-BDP was more stable than BDP, thus gave a potential to increase the chemical reactions between the components of the PC/ABS{sub PTFE}+Aryl phosphate, whereas more reactive BEP was expected to increase the cross linking activity with the polymer matrix. Nevertheless, the corresponding blends did not enhance the flame retardancy compared to PC/ABS{sub PTFE}+BDP. BEP in PC/ABS{sub PTFE} preferred to cross-link with itself instead of with PC, thus it showed poor fire protection performance. TMC-BDP gave as good results as BDP in PC/ABS PTFE material. The results delivered evidence that BDP possesses a high degree of optimization in PC/ABS{sub PTFE} system. To provide a novel impact modifier improving not only mechanical properties but also the fire retardancy of PC/BDP material, the replacement of highly flammable acrylonitrile-butadiene-styrene (ABS) with silicon acrylate rubber (SiR) with high content of polydimethylsiloxane (PDMS) was studied. In PC/SiR{sub PTFE}/BDP the replacement of ABS is beneficial, but PDMS worsened the BDP gas phase and condensed phase action. PDMS reacted also with PC during combustion. PDMS-PC and PDMS-BDP interactions led to silicon dioxide. In fact, the

  2. Chemical Solutions of Fire Protection Problems

    Directory of Open Access Journals (Sweden)

    Vakhitova, L.M.

    2015-11-01

    Full Text Available The modern approaches to the creation of fire protective coatings by modifying intumescent systems by nanomaterials with study of the chemical reaction mechanisms under the high temperatures influence were considered. A systematic study of the interactions of components of polyphosphate type intumescent blend were carried out, a well-defined correlations between the directions of chemical processes and fire retardant properties of intumescent coatings were found. Efficient ways to simultaneous increase of fireprotective efficiency and performance characteristics of intumescent coatings (operatin life, resistance to environmental factors and bioсontamination were proposed. The results of fundamental research allowed to develop new formulations of flame retardant compositions, whose properties have been confirmed by tests in accordance with existing standardized methods, these results were introduced into production.

  3. Orthognathic surgery for mentally retarded patients

    NARCIS (Netherlands)

    Becking, A. G.; Tuinzing, D. B.

    1991-01-01

    The surgical treatment of mentally retarded children for esthetic reasons is discussed. In mentally retarded adults a facial deformity can give rise to functional problems; in some cases a facial deformity can stigmatize the mental state. In selected cases orthognathic surgery may offer a solution

  4. Body Awareness in Children with Mental Retardation

    Science.gov (United States)

    Simons, Johan; Dedroog, Inge

    2009-01-01

    The body awareness of 124 toddlers with mental retardation and of 124 children developing normally matched to them on age and gender was examined. Twenty-nine of the children with mental retardation were diagnosed as Down syndrome (DS). The "Pointing and Naming" Test of Berges and Lezine [Berges, J., & Lezine, I. (1978). "Test d'imitation de…

  5. Political Philosophy and the Mentally Retarded.

    Science.gov (United States)

    Stanovich, Keith E.

    The effects of Social Darwinism, eugenics, and contemporary political conservatism on the status of advocacy efforts for the mentally retarded are reviewed. Provided are historical sketches of Social Darwinism, which viewed the retarded as members of an inferior race, and eugenics, which argued for sterilization of the "genetically…

  6. Noncitizen: Plight of the Mentally Retarded

    Science.gov (United States)

    Skarnulis, Ed

    1974-01-01

    Mentally retarded citizens have been denied their human and civil rights, not only by the public, but by professionals--including social workers. The author claims that most programs for the mentally retarded are, at best, dehumanizing. Professionals have an ethical obligation to refuse to refer children to such programs. (Author)

  7. Sustained Attention of Adults with Mental Retardation.

    Science.gov (United States)

    Tomporowski, Phillip D.; Allison, Pamela

    1988-01-01

    The sustained attention of 23 young adults with mild mental retardation and nonretarded subjects was assessed. Findings suggested that the sustained attention of the retarded differs from that of the nonretarded on those vigilance tasks that place demands on memory abilities. (Author/DB)

  8. The Mentally Retarded Offender and Corrections.

    Science.gov (United States)

    Santamour, Miles; West, Bernadette

    The booklet provides an overview of the issues involved in correctional rehabilitation for the mentally retarded offender. Reviewed are clinical and legal definitions of criminal behavior and retardation, and discussed are such issues as law enforcement and court proceedings problems, pros and cons of special facilities, labeling, normalization,…

  9. AUTISTIC FEATURES IN CHILDREN WITH MENTAL RETARDATION

    Science.gov (United States)

    Kar, Nilamadhab; Khanna, Rakesh; Kar, Gopal Chandra

    1997-01-01

    Most of the autistic disorder patients are also mentally retarded and many mentally retarded persons exhibit autistic symptoms. By using a standard instrument (Ritvo-Freeman Real Life Rating Scale) the autistic features of the mentally retarded children were studied. The study also examined the influence of age, sex and level of mental retardation on the occurrence of autistic symptoms. Children who came for consultation to child psychiatric unit were compared with those at a school for children with mental retardation receiving stimulation. Male children from child psychiatric unit had significantly higher scores than those from the school. Social and language impairment could be reliably identified and grouped. It was possible to diagnose the syndrome of autism in children with mental retardation in a significant number (9.6%)as compared to that was possible only clinically (1.9%). More number of children with severe/ profound mental retardation could be diagnosed as autistic. The autistic syndrome in children with mental retardation can be picked up more effectively by the use of structured instrument. PMID:21584097

  10. Smouldering Fires in the Earth System

    Science.gov (United States)

    Rein, G.

    2012-04-01

    Smouldering fires, the slow, low-temperature, flameless burning, represent the most persistent type of combustion phenomena and the longest continuously fires on Earth system. Indeed, smouldering mega-fires of peatlands occur with some frequency during the dry session in, for example, Indonesia, Canada, Russia, UK and USA. Smouldering fires propagate slowly through organic layers of the ground and can reach depth >5 m if large cracks, natural piping or channel systems exist. It threatens to release sequestered carbon deep into the soil. Once ignited, they are particularly difficult to extinguish despite extensive rains, weather changes or fire-fighting attempts, and can persist for long periods of time (months, years) spreading deep and over extensive areas. Recent figures at the global scale estimate that average annual greenhouse gas emissions from smouldering fires are equivalent to 15% of man-made emissions. These fires are difficult or impossible to detect with current remote sensing methods because the chemistry is significantly different, their thermal radiation signature is much smaller, and the plume is much less buoyant. These wildfires burn fossil fuels and thus are a carbon-positive fire phenomena. This creates feedbacks in the climate system because soil moisture deficit and self-heating are enchanted under warmer climate scenarios and lead to more frequent fires. Warmer temperatures at high latitudes are resulting in more frequent Artic fires. Unprecedented permafrost thaw is leaving large soil carbon pools exposed to smouldering fires for the fist time since millennia. Although interactions between flaming fires and the Earth system have been a central focus, smouldering fires are as important but have received very little attention. DBut differences with flaming fires are important. This paper reviews the current knowledge on smouldering fires in the Earth system regarding combustion dynamics, damage to the soil, emissions, remote sensing and

  11. CT findings of mentally retarded patients

    International Nuclear Information System (INIS)

    Mikami, Akihiro; Watanabe, Hiroshi

    1984-01-01

    Cranial CT findings were compared according to the age group in 192 mentally retarded patients aged from 15 to 59 years and in 132 control subjects. Enlargement of the ventricles, cisterns or fissures was judged. The incidence of ''enlargement'' was higher, irrespective of age, in mentally retarded group than in the control group. When the mentally retarded patients were divided into the group with pathologic symptoms and the group without them, the incidence of ''enlargement'' was higher in the former group than in the control group, but there was no significant difference between the latter group and the control group. There was no consistent relationship between the degree of mental retardation and the incidence of ''enlargement''. Many of the mentally retarded patients with pathologic symptoms tended to have a wide range of enlargement, while many of the patients without them had narrowed lateral ventricle. (Namekawa, K.)

  12. CASE REPORT OF A MENTALLY RETARDED CHILD

    Directory of Open Access Journals (Sweden)

    Vasilka GALEVSKA

    2006-06-01

    Full Text Available Mental retardation is a complex individual and social problem. According to WHO, around 1-3 % of world population are mentally retarded people and the percentage between school children is around 2 %.The development of a mentally retarded child depends on factors related to the disability itself, all the limitations and characteristics which results from that. But, physical, psychical, educational and social development of a mentally retarded child, also, depend on other conditions, such as the family and the wider environment, their reactions, attitudes, awareness and sensitivity for special needs of the child, as well as their preparedness and possibilities to respond.At the same time, it is necessary that the mentally retarded child is detected and diagnosed in time, as well as the early start of an adequate treatment.

  13. Organic chemistry

    International Nuclear Information System (INIS)

    2003-08-01

    This book with sixteen chapter explains organic chemistry on linkage isomerism such as alkane, cycloalkane, alkene, aromatic compounds, stereo selective isomerization, aromatic compounds, stereo selective isomerization, organic compounds, stereo selective isomerization, organic halogen compound, alcohol, ether, aldehyde and ketone, carboxylic acid, dicarboxylic acid, fat and detergent, amino, carbohydrate, amino acid and protein, nucleotide and nucleic acid and spectroscopy, a polymer and medical chemistry. Each chapter has introduction structure and characteristic and using of organic chemistry.

  14. Radiation chemistry

    Energy Technology Data Exchange (ETDEWEB)

    None

    1973-07-01

    Research progress is reported on radiation chemistry of heavy elements that includes the following topics: radiation chemistry of plutonium in nitric acid solutions (spectrophotometric analysis and gamma radiolysis of Pu(IV) and Pu(VI) in nitric acid solution); EPR studies of intermediates formed in radiolytic reactions with aqueous medium; two-phase radiolysis and its effect on the distribution coefficient of plutonium; and radiation chemistry of nitric acid. (DHM)

  15. Technetium chemistry

    International Nuclear Information System (INIS)

    Burns, C.; Bryan, J.; Cotton, F.; Ott, K.; Kubas, G.; Haefner, S.; Barrera, J.; Hall, K.; Burrell, A.

    1996-01-01

    Technetium chemistry is a young and developing field. Despite the limited knowledge of its chemistry, technetium is the workhorse for nuclear medicine. Technetium is also a significant environmental concern because it is formed as a byproduct of nuclear weapons production and fission-power generators. Development of new technetium radio-pharmaceuticals and effective environmental control depends strongly upon knowledge of basic technetium chemistry. The authors performed research into the basic coordination and organometallic chemistry of technetium and used this knowledge to address nuclear medicine and environmental applications. This is the final report of a three-year Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL)

  16. Chemistry Technology

    Data.gov (United States)

    Federal Laboratory Consortium — Chemistry technology experts at NCATS engage in a variety of innovative translational research activities, including:Design of bioactive small molecules.Development...

  17. Fiscal 1999 survey report. Part 2. Research study on restraint of carbon dioxide generation by green chemistry; 1999 nendo green chemistry ni yoru CO{sub 2} hassei yokusei ni kakawaru chosa kenkyu. 2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    In connection with green chemistry, a concept of bringing paradigm shift to chemical technologies as something that makes reduction in environmental load compatible with economic activities; surveys were made this year on the developments of fine chemicals from renewable resources such as cellulose among the cases of developing chemical substances/products to be called 'green chemicals' reducing environmental load; developments of surfactants produced by certain microorganism, plastic additives with reduced pollutant loads, particularly fire retardants and environmentally benign reactant solvents; concept of green chemistry in the development of chlorofluorocarbon-alternatives; and up-to-date technological level concerning a design method of chemical materials and an estimation method for chemical safety using quantum chemistry calculation. In regard to the chemical materials and products intrinsically containing a certain level of risk, R and D should be reinforced and accelerated in the future on the alternative materials/products reducing their toxicity. In this case, along with the importance of discussing compatibility of technological possibility with economical adaptability, sociological study seems to be necessary in incorporating environmental load reduction into economic evaluation. (NEDO)

  18. Recycling of plastic waste: Screening for brominated flame retardants (BFRs).

    Science.gov (United States)

    Pivnenko, K; Granby, K; Eriksson, E; Astrup, T F

    2017-11-01

    Flame retardants are chemicals vital for reducing risks of fire and preventing human casualties and property losses. Due to the abundance, low cost and high performance of bromine, brominated flame retardants (BFRs) have had a significant share of the market for years. Physical stability on the other hand, has resulted in dispersion and accumulation of selected BFRs in the environment and receiving biota. A wide range of plastic products may contain BFRs. This affects the quality of waste plastics as secondary resource: material recycling may potentially reintroduce the BFRs into new plastic product cycles and lead to increased exposure levels, e.g. through use of plastic packaging materials. To provide quantitative and qualitative data on presence of BFRs in plastics, we analysed bromophenols (tetrabromobisphenol A (TBBPA), dibromophenols (2,4- and 2,6-DBP) and 2,4,6-tribromophenol (2,4,6-TBP)), hexabromocyclododecane stereoisomers (α-, β-, and γ-HBCD), as well as selected polybrominated diphenyl ethers (PBDEs) in samples of household waste plastics, virgin and recycled plastics. A considerable number of samples contained BFRs, with highest concentrations associated with acrylonitrile butadiene styrene (ABS, up to 26,000,000ngTBBPA/g) and polystyrene (PS, up to 330,000ng∑HBCD/g). Abundancy in low concentrations of some BFRs in plastic samples suggested either unintended addition in plastic products or degradation of higher molecular weight BFRs. The presence of currently restricted flame retardants (PBDEs and HBCD) identified in the plastic samples illustrates that circular material flows may be contaminated for extended periods. The screening clearly showed a need for improved documentation and monitoring of the presence of BFRs in plastic waste routed to recycling. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Engineering Biodegradable Flame Retardant Wood-Plastic Composites

    Science.gov (United States)

    Zhang, Linxi

    Wood-plastic composites (WPCs), which are produced by blending wood and polymer materials, have attracted increasing attentions in market and industry due to the low cost and excellent performance. In this research, we have successfully engineered WPC by melt blending Polylactic Acid (PLA) and Poly(butylene adipate-co-terphthalate) (PBAT) with recycled wood flour. The thermal property and flammability of the composite are significantly improved by introducing flame retardant agent resorcinol bis(biphenyl phosphate) (RDP). The mechanical and morphological properties are also investigated via multiple techniques. The results show that wood material has increased toughness and impact resistance of the PLA/PBAT polymer matrix. SEM images have confirmed that PLA and PBAT are immiscible, but the incompatibility is reduced by the addition of wood. RDP is initially dispersed in the blends evenly. It migrates to the surface of the sample after flame application, and serves as a barrier between the fire and underlying polymers and wood mixture. It is well proved in the research that RDP is an efficient flame retardant agent in the WPC system.

  20. Catalytic degradation of brominated flame retardants by copper oxide nanoparticles

    Science.gov (United States)

    Dror, I.; Yecheskel, Y.; Berkowitz, B.

    2013-12-01

    Brominated flame retardants (BFRs) have been added to various products like plastic, textile, electronics and synthetic polymers at growing rates. In spite of the clear advantages of reducing fire damages, many of these BFRs may be released to the environment after their beneficial use which may lead to contamination of water resources. In this work we present the catalytic degradation of two brominated flame retardants (BFRs), tribromoneopentyl alcohol (TBNPA) and 2,4 dibromophenol (2,4-DBP) by copper oxide nanoparticles (nCuO) in aqueous solution. The degradation kinetics, the debromination, and the formation of intermediates by nCuO catalysis are compared to Fenton oxidation and to reduction by nano zero-valent iron (nZVI). The two studied BFRs are shown to degrade fully by the nCuO system within hours to days. Shorter reaction times showed differences in reaction pathways and kinetics for the two compounds. The 2,4-DBP showed faster degradation than TBNPA, by nCuO catalysis. Relatively high resistance to degradation was recorded for 2,4-DBP with nZVI, yielding 20% degradation after 24 h, while the TBNPA was degraded by 85% within 12 hours. A catalytic mechanism for radical generation and BFR degradation by nCuO is proposed. It is further suggested that H2O2 plays an essential role in the activation of the catalyst.

  1. Fire safety

    International Nuclear Information System (INIS)

    Keski-Rahkonen, O.; Bjoerkman, J.; Hostikka, S.; Mangs, J.; Huhtanen, R.; Palmen, H.; Salminen, A.; Turtola, A.

    1998-01-01

    According to experience and probabilistic risk assessments, fires present a significant hazard in a nuclear power plant. Fires may be initial events for accidents or affect safety systems planned to prevent accidents and to mitigate their consequences. The project consists of theoretical work, experiments and simulations aiming to increase the fire safety at nuclear power plants. The project has four target areas: (1) to produce validated models for numerical simulation programmes, (2) to produce new information on the behavior of equipment in case of fire, (3) to study applicability of new active fire protecting systems in nuclear power plants, and (4) to obtain quantitative knowledge of ignitions induced by important electric devices in nuclear power plants. These topics have been solved mainly experimentally, but modelling at different level is used to interpret experimental data, and to allow easy generalisation and engineering use of the obtained data. Numerical fire simulation has concentrated in comparison of CFD modelling of room fires, and fire spreading on cables on experimental data. So far the success has been good to fair. A simple analytical and numerical model has been developed for fire effluents spreading beyond the room of origin in mechanically strongly ventilated compartments. For behaviour of equipment in fire several full scale and scaled down calorimetric experiments were carried out on electronic cabinets, as well as on horizontal and vertical cable trays. These were carried out to supply material for CFD numerical simulation code validation. Several analytical models were developed and validated against obtained experimental results to allow quick calculations for PSA estimates as well as inter- and extrapolations to slightly different objects. Response times of different commercial fire detectors were determined for different types of smoke, especially emanating from smoldering and flaming cables to facilitate selection of proper detector

  2. Windscale fire

    International Nuclear Information System (INIS)

    Auxier, J.A.

    1986-01-01

    A graphite fire in the Windscale No. 1 reactor occurred during the period October 8-12, 1957. The Windscale reactors were located on a coastal plain in northwest England and were used to produce plutonium. A great wealth of information was gathered on the causes, handling, decontamination, and environmental effects of reactor accidents. Topics of discussion include: the cause of the fire; handling of the incident; radiation doses to the population; and radiation effects on the population

  3. Global Consumption of Flame Retardants and Related Environmental Concerns: A Study on Possible Mechanical Recycling of Flame Retardant Textiles

    Directory of Open Access Journals (Sweden)

    Sohail Yasin

    2016-05-01

    Full Text Available Flame retardants (FRs have been around us for decades to increase the chances of survival against fire or flame by limiting its propagation. The FR textiles, irrespective of their atmospheric presence are used in baby clothing, pushchairs, car seats, etc. The overall FR market in Asia, Europe, and the United States in 2007 was around 1.8 million metric tonnes. It is estimated that the worldwide consumption of FRs will reach 2.8 million tonnes in 2018. Unfortunately, a sustainable approach for textile waste, especially in the case of FR textiles, is absent. Incineration and landfill of FR textiles are hindered by various toxic outcomes. To address the need for sustainable methods of discarding FR textiles, the mechanical recycling of cotton curtains was evaluated.

  4. The measurement of retardation in depression.

    Science.gov (United States)

    Dantchev, N; Widlöcher, D J

    1998-01-01

    The description of clinical features helps to distinguish between depressive illness and nondepressive psychic pain and enables the clinician to decide whether prescription of an antidepressant is beneficial. Psychomotor retardation is probably a central feature of depression, and this review discusses the methods available for measuring it. The Salpêtrière Retardation Rating Scale (SRRS) specifically measures psychomotor retardation; the scale and applications are described. Means of measuring motor and speech activity and an experimental approach for understanding the process underlying psychomotor retardation are reviewed. Comparison of the SRRS and other rating scale scores demonstrates that retardation is related to depression severity and therapeutic change and is a good criterion for prediction of therapeutic effect. The SRRS has been used to show that selective antidepressants target specific clinical dimensions of depression depending on the patient subgroup treated. Measures of motor and speech activity are sensitive to therapeutic response. Choice Reaction Time and Simple Reaction Time tasks are particularly suited for examining psychomotor retardation because they test the decision process while avoiding motivation and attention interference. Psychomotor retardation is a constant and probably central feature of depression. Means available for measuring it can be used to assess the effects of antidepressants on specific clinical dimensions.

  5. Current organic chemistry

    National Research Council Canada - National Science Library

    1997-01-01

    Provides in depth reviews on current progress in the fields of asymmetric synthesis, organometallic chemistry, bioorganic chemistry, heterocyclic chemistry, natural product chemistry, and analytical...

  6. Nuclear chemistry

    International Nuclear Information System (INIS)

    Vertes, A.; Kiss, I.

    1987-01-01

    This book is an introduction to the application of nuclear science in modern chemistry. The first group of chapters discuss the basic phenomena and concepts of nuclear physics with emphasis on their relation to chemical problems, including the main properties and the composition of atomic nuclei, nuclear reactions, radioactive decay and interactions of radiation with matter. These chapters provide the basis for understanding the following chapters which encompass the wide scope of nuclear chemistry. The methods of the investigation of chemical structure based on the interaction of nuclear radiation with matter including positronium chemistry and other exotic atoms is elaborated in particular detail. Separate chapters are devoted to the use of radioactive tracers, the chemical consequences of nuclear processes (i.e. hot atom chemistry), radiation chemistry, isotope effects and their applications, and the operation of nuclear reactors

  7. Nuclear chemistry

    International Nuclear Information System (INIS)

    Vertes, A.; Kiss, I.

    1987-01-01

    This book is an introduction to the application of nuclear science in modern chemistry. The first group of chapters discuss the basic phenomena and concepts of nuclear physics with emphasis on their relation to chemical problems, including the main properties and the composition of atomic nuclei, nuclear reactions, radioactive decay and interactions of radiation with matter. These chapters provide the basis for understanding the following chapters which encompass the wide scope of nuclear chemistry. The methods of the investigation of chemical structure based on the interaction of nuclear radiation with matter including positronium chemistry and other exotic atoms is elaborated in particular detail. Separate chapters are devoted to the use of radioactive tracers, the chemical consequences of nuclear processes (i.e. hot atom chemistry), radiation chemistry, isotope effects and their applications, and the operation of nuclear reactors. (Auth.)

  8. SLEEP DISORDERS IN MENTALLY RETARDED CHILDREN

    Directory of Open Access Journals (Sweden)

    I. A. Kelmanson

    2014-01-01

    Full Text Available The paper presents the study of the association between sleep disturbances and mental retardation in children. Attention is paid to the instant connection between sleep neurophysiology and intellectual progress, as well as between sleep disorders and the pathogenesis of mental retardation in children. The data on characteristic forms of sleep disturbances, including bed-time resistance, frequent night awakenings, parasomnias, abnormal sleep structure, and notably reduced REM-sleep proportion are provided. The potential role of abnormal melatonin production in the origins of sleep disturbances in children with mental retardation is discussed. Certain approaches to pharmacological and non-pharmacological corrections of sleep disorders are outlined.

  9. Recent Developments in Organophosphorus Flame Retardants Containing P-C Bond and Their Applications

    Directory of Open Access Journals (Sweden)

    Sophie Wendels

    2017-07-01

    Full Text Available Organophosphorus compounds containing P-C bonds are increasingly developed as flame retardant additives due to their excellent thermal and hydrolytic stability and ease of synthesis. The latest development (since 2010 in organophosphorus flame retardants containing P-C bonds summarized in this review. In this review, we have broadly classified such phosphorus compounds based on the carbon unit linked to the phosphorus atom i.e., could be a part of either an aliphatic or an aromatic unit. We have only considered those published literature where a P-C bond was created as a part of synthetic strategy to make either an intermediate or a final organophosphorus compound with an aim to use it as a flame retardant. General synthetic strategies to create P-C bonds are briefly discussed. Most popular synthetic strategies used for developing P-C containing phosphorus based flame retardants include Michael addition, Michaelis–Arbuzov, Friedels–Crafts and Grignard reactions. In general, most flame retardant derivatives discussed in this review have been prepared via a one- to two-step synthetic strategy with relatively high yields greater than 80%. Specific examples of P-C containing flame retardants synthesized via suitable synthetic strategy and their applications on various polymer systems are described in detail. Aliphatic phosphorus compounds being liquids or low melting solids are generally applied in polymers via coatings (cellulose or are incorporated in the bulk of the polymers (epoxy, polyurethanes during their polymerization as reactive or non-reactive additives. Substituents on the P atoms and the chemistry of the polymer matrix greatly influence the flame retardant behavior of these compounds (condensed phase vs. the gas phase. Recently, aromatic DOPO based phosphinate flame retardants have been developed with relatively higher thermal stabilities (>250 °C. Such compounds have potential as flame retardants for high temperature processable

  10. Preliminary report on fire protection research program (July 6, 1977 test)

    International Nuclear Information System (INIS)

    Klamerus, L.J.

    1977-10-01

    This preliminary report describes a fire test performed at Sandia Laboratories on an array of cable trays filled with fire retardant (IEEE 383 qualified) electrical cable. The cable trays were arranged in an open-space horizontal configuration with the separation distances of Regulatory Guide 1.75 between those trays representing redundant safety divisions. Propane burners were used to produce a fully developed cable fire in one tray which then was allowed to interact with other trays. From this test it appears that it is possible for a fire to propagate across the vertical separation distance between safety divisions, if a fully developed cable fire is the initiating event

  11. Platinum-doped titanate nanotubes/reduced graphene oxide: photocatalytic activity and flame retardancy

    Science.gov (United States)

    Liu, Guangya; Sang, Bin; Zhou, Zhiqi; Li, Zhiwei

    2018-01-01

    The ‘white pollution’ produced by wasted flexible polyvinyl chloride (PVC) with poor degradation ability and the potential fire hazard of PVC with high flammability not only restrict their application but also cause serious environmental problem. Thus platinum-doped titanate nanotubes/reduced graphene oxide (denoted as Pt-TNTs/rGO) nanocomposites were prepared by a facile method in order to improve the visible photodegradation and get rid of the ‘white pollution’ as well as flame retardancy of PVC. The photodegradation activity and flame retardancy effect of the as-prepared Pt-TNTs/rGO nanocomposites were investigated by ultraviolet and visible light irradiation as well as cone calorimetry. Results show that the Pt-TNTs/rGO-PVC nanocomposites exhibit enhanced visible light photodegradation performance (with mass loss being 6.5%) during 15 day exposure to solar irradiation, and good flame retardancy (providing a 44% reduction of total smoke release as compared with that of PVC matrix). Besides, Pt-TNTs/rGO-PVC nanocomposites show suppressed smoke and reduced CO production as compared with the PVC matrix. These results demonstrate that Pt-TNTs/rGO not only get rid of the ‘white pollution’ as the photocatalyst but also improve the fire safety of PVC as the flame retardant. This could be ascribed to the combination effect between Pt-TNTs and rGO. The present research, hopefully, is to pave a potential pathway to constructing polymer-matrix composites with desired photodegradation activity and flame retardancy, thereby shedding light on simultaneously dealing with the ‘white pollution’ and high flammability of polymer matrix like PVC.

  12. Education of Mentally Retarded Adults

    Directory of Open Access Journals (Sweden)

    Dora Jelenc

    2000-12-01

    Full Text Available Adult education of people with severe, modest and profound mental retardation got only recently an important place in the special education theory and practice. It could be established that in this area both in the intentional as well as in the contentual field the meaningfull shift has been achieved. Today we are talking about authonomy and rights of these people to taking part in a decission-making about the way of their living, but on the other  side the fast development and changes in society are again and again compelling this people to the decisions which they are not able to put into effect and which are burdening them and making them dependent of others. This could partly be prevented by continuing education as it is also true for them that in the stage of initial education they cannot subdue everything what they would need later in their life. Next to the findings of the foreign experts this has been confirmed as well in the first our investigations in this area. Some of the findings will be presented in our paper.

  13. A, a Brominated Flame Retardant

    Directory of Open Access Journals (Sweden)

    Tomomi Takeshita

    2013-01-01

    Full Text Available Tetrabromobisphenol A (TBBPA, a brominated flame retardant, has been found to exacerbate pneumonia in respiratory syncytial virus- (RSV- infected mice. We examined the effect of Brazilian propolis (AF-08 on the exacerbation of RSV infection by TBBPA exposure in mice. Mice were fed a powdered diet mixed with 1% TBBPA alone, 0.02% AF-08 alone, or 1% TBBPA and 0.02% AF-08 for four weeks and then intranasally infected with RSV. TBBPA exposure increased the pulmonary virus titer and level of IFN-γ, a representative marker of pneumonia due to RSV infection, in the lungs of infected mice without toxicity. AF-08 was significantly effective in reducing the virus titers and IFN-γ level increased by TBBPA exposure. Also, AF-08 significantly reduced proinflammatory cytokine (TNF-α and IL-6 levels in the lungs of RSV-infected mice with TBBPA exposure, but Th2 cytokine (IL-4 and IL-10 levels were not evidently increased. Neither TBBPA exposure nor AF-08 treatment affected the anti-RSV antibody production in RSV-infected mice. In flow cytometry analysis, AF-08 seemed to be effective in reducing the ratio of pulmonary CD8a+ cells in RSV-infected mice with TBBPA exposure. TBBPA and AF-08 did not exhibit anti-RSV activity in vitro. Thus, AF-08 probably ameliorated pneumonia exacerbated by TBBPA exposure in RSV-infected mice by limiting excess cellular immune responses.

  14. The Political Values of Mentally Retarded Citizens.

    Science.gov (United States)

    Green, Barbara B.; Klein, Nancy K.

    1980-01-01

    The findings indicated that the retarded are affected by the process of political socialization much like their nonretarded peers. In forming a ranking of goal-values, age and socioeconomic status outweighed differences in cognitive ability. (Author/DLS)

  15. Nanocellular foam with solid flame retardant

    Science.gov (United States)

    Chen, Liang; Kelly-Rowley, Anne M.; Bunker, Shana P.; Costeux, Stephane

    2017-11-21

    Prepare nanofoam by (a) providing an aqueous solution of a flame retardant dissolved in an aqueous solvent, wherein the flame retardant is a solid at 23.degree. C. and 101 kiloPascals pressure when in neat form; (b) providing a fluid polymer composition selected from a solution of polymer dissolved in a water-miscible solvent or a latex of polymer particles in a continuous aqueous phase; (c) mixing the aqueous solution of flame retardant with the fluid polymer composition to form a mixture; (d) removing water and, if present, solvent from the mixture to produce a polymeric composition having less than 74 weight-percent flame retardant based on total polymeric composition weight; (e) compound the polymeric composition with a matrix polymer to form a matrix polymer composition; and (f) foam the matrix polymer composition into nanofoam having a porosity of at least 60 percent.

  16. Quantum chemistry

    CERN Document Server

    Lowe, John P

    1993-01-01

    Praised for its appealing writing style and clear pedagogy, Lowe's Quantum Chemistry is now available in its Second Edition as a text for senior undergraduate- and graduate-level chemistry students. The book assumes little mathematical or physical sophistication and emphasizes an understanding of the techniques and results of quantum chemistry, thus enabling students to comprehend much of the current chemical literature in which quantum chemical methods or concepts are used as tools. The book begins with a six-chapter introduction of standard one-dimensional systems, the hydrogen atom,

  17. Fire resistance properties of ceramic wool fiber reinforced intumescent coatings

    Energy Technology Data Exchange (ETDEWEB)

    Amir, N., E-mail: norlailiamir@petronas.com.my; Othman, W. M. S. W., E-mail: wamosa@gmail.com; Ahmad, F., E-mail: faizahmad@petronas.com.my [Mechanical Engineering Department, Universiti Teknologi PETRONAS Bandar Seri Iskandar, 31750 Tronoh, Perak (Malaysia)

    2015-07-22

    This research studied the effects of varied weight percentage and length of ceramic wool fiber (CWF) reinforcement to fire retardant performance of epoxy-based intumescent coating. Ten formulations were developed using ammonium polyphosphate (APP), expandable graphite (EG), melamine (MEL) and boric acid (BA). The mixing was conducted in two stages; powdered materials were grinded in Rocklabs mortar grinder and epoxy-mixed using Caframo mixer at low speed mixing. The samples were applied on mild steel substrate and exposed to 500°C heat inside Carbolite electric furnace. The char expansion and its physical properties were observed. Scanning electron microscopy (SEM) analyses were conducted to inspect the fiber dispersion, fiber condition and the cell structure of both coatings and chars produced. Thermogravimetric analyses (TGA) were conducted to study the thermal properties of the coating such as degradation temperature and residual weight. Fire retardant performance was determined by measuring backside temperature of substrate in 1-hour, 1000°C Bunsen burner test according to UL 1709 fire regime. The results showed that intumescent coating reinforced with CWF produced better fire resistance performance. When compared to unreinforced coating, formulation S6-15 significantly reduced steel temperature at approximately 34.7% to around 175°C. However, higher fiber weight percentage had slightly decreased fire retardant performance of the coating.

  18. Fire resistance properties of ceramic wool fiber reinforced intumescent coatings

    International Nuclear Information System (INIS)

    Amir, N.; Othman, W. M. S. W.; Ahmad, F.

    2015-01-01

    This research studied the effects of varied weight percentage and length of ceramic wool fiber (CWF) reinforcement to fire retardant performance of epoxy-based intumescent coating. Ten formulations were developed using ammonium polyphosphate (APP), expandable graphite (EG), melamine (MEL) and boric acid (BA). The mixing was conducted in two stages; powdered materials were grinded in Rocklabs mortar grinder and epoxy-mixed using Caframo mixer at low speed mixing. The samples were applied on mild steel substrate and exposed to 500°C heat inside Carbolite electric furnace. The char expansion and its physical properties were observed. Scanning electron microscopy (SEM) analyses were conducted to inspect the fiber dispersion, fiber condition and the cell structure of both coatings and chars produced. Thermogravimetric analyses (TGA) were conducted to study the thermal properties of the coating such as degradation temperature and residual weight. Fire retardant performance was determined by measuring backside temperature of substrate in 1-hour, 1000°C Bunsen burner test according to UL 1709 fire regime. The results showed that intumescent coating reinforced with CWF produced better fire resistance performance. When compared to unreinforced coating, formulation S6-15 significantly reduced steel temperature at approximately 34.7% to around 175°C. However, higher fiber weight percentage had slightly decreased fire retardant performance of the coating

  19. Fire resistance properties of ceramic wool fiber reinforced intumescent coatings

    Science.gov (United States)

    Amir, N.; Othman, W. M. S. W.; Ahmad, F.

    2015-07-01

    This research studied the effects of varied weight percentage and length of ceramic wool fiber (CWF) reinforcement to fire retardant performance of epoxy-based intumescent coating. Ten formulations were developed using ammonium polyphosphate (APP), expandable graphite (EG), melamine (MEL) and boric acid (BA). The mixing was conducted in two stages; powdered materials were grinded in Rocklabs mortar grinder and epoxy-mixed using Caframo mixer at low speed mixing. The samples were applied on mild steel substrate and exposed to 500°C heat inside Carbolite electric furnace. The char expansion and its physical properties were observed. Scanning electron microscopy (SEM) analyses were conducted to inspect the fiber dispersion, fiber condition and the cell structure of both coatings and chars produced. Thermogravimetric analyses (TGA) were conducted to study the thermal properties of the coating such as degradation temperature and residual weight. Fire retardant performance was determined by measuring backside temperature of substrate in 1-hour, 1000°C Bunsen burner test according to UL 1709 fire regime. The results showed that intumescent coating reinforced with CWF produced better fire resistance performance. When compared to unreinforced coating, formulation S6-15 significantly reduced steel temperature at approximately 34.7% to around 175°C. However, higher fiber weight percentage had slightly decreased fire retardant performance of the coating.

  20. Active Fire Mapping Program

    Science.gov (United States)

    Active Fire Mapping Program Current Large Incidents (Home) New Large Incidents Fire Detection Maps MODIS Satellite Imagery VIIRS Satellite Imagery Fire Detection GIS Data Fire Data in Google Earth ...

  1. Fire Safety (For Parents)

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Fire Safety KidsHealth / For Parents / Fire Safety What's in ... event of a fire emergency in your home. Fire Prevention Of course, the best way to practice ...

  2. Fire Research Enclosure

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Simulates submarine fires, enclosed aircraft fires, and fires in enclosures at shore facilities .DESCRIPTION: FIRE I is a pressurizable, 324 cu m(11,400 cu...

  3. Mental Retardation, Poverty and Community Based Rehabilitation

    Directory of Open Access Journals (Sweden)

    Einar Helander

    2009-10-01

    Full Text Available A person with moderate mental retardation would, in a western country, be "diagnosed" early on in life. Consequently, such a child is likely to be sent for special education. Given the high level of job requirements, such a person is unlikely to be employed in the open market later in life. Mental retardation is one of the most frequent disabilities in most studies, mental retardation is found in about three percent of the population. Persons even with mild mental retardation have very large difficulties finding employment and are for this reason often deprived of opportunities for suitable and productive income generation this is why most stay poor. But disability does not only cause poverty poverty itself causes disability. This study follows an analysis, based on a review of the Swedish programme for mental retardation during the period 1930-2000. It is concluded that in Sweden a very large proportion of mild and moderate mental retardation has been eliminated though the combination of poverty alleviation with a community-based rehabilitation programme. For these situations a pro-active programme analysing and meeting the needs of the target groups should be useful as a means to achieve poverty alleviation.

  4. Materials Chemistry

    CERN Document Server

    Fahlman, Bradley D

    2011-01-01

    The 2nd edition of Materials Chemistry builds on the strengths that were recognized by a 2008 Textbook Excellence Award from the Text and Academic Authors Association (TAA). Materials Chemistry addresses inorganic-, organic-, and nano-based materials from a structure vs. property treatment, providing a suitable breadth and depth coverage of the rapidly evolving materials field. The 2nd edition continues to offer innovative coverage and practical perspective throughout. After briefly defining materials chemistry and its history, seven chapters discuss solid-state chemistry, metals, semiconducting materials, organic "soft" materials, nanomaterials, and materials characterization. All chapters have been thoroughly updated and expanded with, for example, new sections on ‘soft lithographic’ patterning, ‘click chemistry’ polymerization, nanotoxicity, graphene, as well as many biomaterials applications. The polymer and ‘soft’ materials chapter represents the largest expansion for the 2nd edition. Each ch...

  5. Analytical chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Chae, Myeong Hu; Lee, Hu Jun; Kim, Ha Seok

    1989-02-15

    This book give explanations on analytical chemistry with ten chapters, which deal with development of analytical chemistry, the theory of error with definition and classification, sample and treatment gravimetry on general process of gravimetry in aqueous solution and non-aqueous solution, precipitation titration about precipitation reaction and types, complexometry with summary and complex compound, oxidation-reduction equilibrium on electrode potential and potentiometric titration, solvent extraction and chromatograph and experiment with basic operation for chemical experiment.

  6. Analytical chemistry

    International Nuclear Information System (INIS)

    Chae, Myeong Hu; Lee, Hu Jun; Kim, Ha Seok

    1989-02-01

    This book give explanations on analytical chemistry with ten chapters, which deal with development of analytical chemistry, the theory of error with definition and classification, sample and treatment gravimetry on general process of gravimetry in aqueous solution and non-aqueous solution, precipitation titration about precipitation reaction and types, complexometry with summary and complex compound, oxidation-reduction equilibrium on electrode potential and potentiometric titration, solvent extraction and chromatograph and experiment with basic operation for chemical experiment.

  7. Green Chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Collison, Melanie

    2011-05-15

    Green chemistry is the science of chemistry used in a way that will not use or create hazardous substances. Dr. Rui Resendes is working in this field at GreenCentre Canada, an offshoot of PARTEQ Innovations in Kingston, Ontario. GreenCentre's preliminary findings suggest their licensed product {sup S}witchable Solutions{sup ,} featuring 3 classes of solvents and a surfactant, may be useful in bitumen oil sands extraction.

  8. Lignin-Modified Carbon Nanotube/Graphene Hybrid Coating as Efficient Flame Retardant

    Directory of Open Access Journals (Sweden)

    Kunlin Song

    2017-11-01

    Full Text Available To reduce fire hazards and expand high-value applications of lignocellulosic materials, thin films comprising graphene nanoplatelets (GnPs and multi-wall carbon nanotubes (CNTs pre-adsorbed with alkali lignin were deposited by a Meyer rod process. Lightweight and highly flexible papers with increased gas impermeability were obtained by coating a protective layer of carbon nanomaterials in a randomly oriented and overlapped network structure. Assessment of the thermal and flammability properties of papers containing as low as 4 wt % carbon nanomaterials exhibited self-extinguishing behavior and yielded up to 83.5% and 87.7% reduction in weight loss and burning area, respectively, compared to the blank papers. The maximum burning temperature as measured by infrared pyrometry also decreased from 834 °C to 705 °C with the presence of flame retardants. Furthermore, papers coated with composites of GnPs and CNTs pre-adsorbed with lignin showed enhanced thermal stability and superior fire resistance than samples treated with either component alone. These outstanding flame-retardant properties can be attributed to the synergistic effects between GnPs, CNTs and lignin, enhancing physical barrier characteristics, formation of char and thermal management of the material. These results provide great opportunities for the development of efficient, cost-effective and environmentally sustainable flame retardants.

  9. Fire Models and Design Fires

    DEFF Research Database (Denmark)

    Poulsen, Annemarie

    The aim of this project is to perform an experimental study on the influence of the thermal feedback on the burning behavior of well ventilated pre-flashover fires. For the purpose an experimental method has been developed. Here the same identical objects are tested under free burn conditions...... carried out by Carleton University and NRC-IRC performed on seven different types of fire loads representing commercial premises, comprise the tests used for the study. The results show that for some of the room test the heat release rate increased due to thermal feedback compared to free burn for a pre......-flashover fire. Two phenomena were observed, that relate well to theory was found. In an incipient phase the heat release rate rose with the temperature of the smoke layer/enclosure boundaries. This increase was also found to depend on the flammability properties of the burning object. The results also...

  10. Intrauterine radiation exposures and mental retardation

    International Nuclear Information System (INIS)

    Miller, R.W.

    1988-01-01

    Small head size and mental retardation have been known as effects of intrauterine exposure to ionizing radiation since the 1920s. In the 1950s, studies of Japanese atomic-bomb survivors revealed that at 4-17 wk of gestation, the greater the dose, the smaller the brain (and head size), and that beginning at 0.5 Gy (50 rad) in Hiroshima, mental retardation increased in frequency with increasing dose. No other excess of birth defects was observed. Otake and Schull (1984) pointed out that the period of susceptibility to mental retardation coincided with that for proliferation and migration of neuronal elements from near the cerebral ventricles to the cortex. Mental retardation could be the result of interference with this process. Their analysis indicated that exposures at 8-15 wk to 0.01-0.02 Gy (1-2 rad) doubled the frequency of severe mental retardation. This estimate was based on small numbers of mentally retarded atomic-bomb survivors. Although nuclear accidents have occurred recently, new cases will hopefully be too rare to provide further information about the risk of mental retardation. It may be possible, however, to learn about lesser impairment. New psychometric tests may be helpful in detecting subtle deficits in intelligence or neurodevelopmental function. One such test is PEERAMID, which is being used in schools to identify learning disabilities due, for example, to deficits in attention, short- or long-term memory, or in sequencing information. This and other tests could be applied in evaluating survivors of intrauterine exposure to various doses of ionizing radiation. The results could change our understanding of the safety of low-dose exposures

  11. 41 CFR 102-80.135 - Who is a qualified fire protection engineer?

    Science.gov (United States)

    2010-07-01

    ... protection engineer? 102-80.135 Section 102-80.135 Public Contracts and Property Management Federal Property... qualified fire protection engineer? A qualified fire protection engineer is defined as an individual with a thorough knowledge and understanding of the principles of physics and chemistry governing fire growth...

  12. Heat shields for aircraft - A new concept to save lives in crash fires.

    Science.gov (United States)

    Neel, C. B.; Parker, J. A.; Fish, R. H.; Henshaw, J.; Newland, J. H.; Tempesta, F. L.

    1971-01-01

    A passenger compartment surrounded by a fire-retardant shell, to protect the occupants long enough for the fire to burn out or for fire-fighting equipment to reach the aircraft and extinguish it, is proposed as a new concept for saving lives in crash fires. This concept is made possible by the recent development of two new fire-retardant materials: a very lightweight foam plastic, called polyisocyanurate foam, and an intumescent paint. Exposed to heat, the intumescent paint expands to many times its original thickness and insulates the surface underneath it. Demonstration tests are illustrated, described and discussed. However, some problems, such as preventing fuselage rupture and protecting windows, must be solved before such a system can be used.

  13. Differentiation of retarded integrals and the divergence theorem for retarded functions with discontinuities

    International Nuclear Information System (INIS)

    Cooperstock, F.I.; Lim, P.H.

    1986-01-01

    Theorems expressing the time derivatives of retarded volume and surface integrals are presented as well as the Gauss divergence theorem for retarded functions with discontinuities. These theorems greatly facilitate the analysis of gravitational radiation from the motion of disjoint matter distributions in general relativity and could find useful application in other branches of physics

  14. Fires in refugee and displaced persons settlements: The current situation and opportunities to improve fire prevention and control.

    Science.gov (United States)

    Kazerooni, Yasaman; Gyedu, Adam; Burnham, Gilbert; Nwomeh, Benedict; Charles, Anthony; Mishra, Brijesh; Kuah, Solomon S; Kushner, Adam L; Stewart, Barclay T

    2016-08-01

    We aimed to describe the burden of fires in displaced persons settlements and identify interventions/innovations that might address gaps in current humanitarian guidelines. We performed a systematic review of: (i) academic and non-academic literature databases; and (ii) guidelines from leading humanitarian agencies/initiatives regarding fire prevention/control. Of the 1521 records retrieved, 131 reports described settlement fires in 31 hosting countries since 1990. These incidents resulted in 487 deaths, 790 burn injuries, displacement of 382,486 individuals and destruction of 50,509 shelters. There was a 25-fold increase in the rate of settlement fires from 1990 to 2015 (0.002-0.051 per 100,000 refugees, respectively). Only 4 of the 15 leading humanitarian agencies provided recommendations about fire prevention/control strategies. Potentially useful interventions/innovations included safer stoves (e.g. solar cookers) and fire retardant shelter materials. The large and increasing number of fires in displaced persons settlements highlights the need to redress gaps in humanitarian fire prevention/control guidelines. The way forward includes: (i) developing consensus among aid agencies regarding fire prevention/control strategies; (ii) evaluating the impact of interventions/innovations on the burden of fires; and (iii) engaging agencies in a broader discussion about protecting camp residents from armed groups. Copyright © 2015 Elsevier Ltd and ISBI. All rights reserved.

  15. [Clinical features of strabismus in psychomotor retardation].

    Science.gov (United States)

    Arias-Cabello, Belina; Arroyo-Yllanes, María Estela; Pérez-Pérez, José Fernando; Fonte-Vázquez, Anselmo

    2016-01-01

    In psychomotor retardation there is an abnormal development of mental, sensory and motor skills associated with ocular manifestations. There are biological and psychosocial risk factors that predispose an individual to neurological damage. From 50% to 80% of patients with strabismus retardation have special features that differentiate it from the rest of strabismus in healthy patients. To determine the most common type of strabismus in patients with psychomotor retardation and their clinical features. Patients with psychomotor retardation and strabismus were included. An ophthalmological examination was performed, as well as an evaluation of the characteristics of strabismus, including perinatal and post-natal history. Esotropia was the most frequent squint with 65.3%, followed by exotropia with 32.7%. The variability in the squint magnitude was 60% in both types, and 6 patients had dissociated vertical deviation. Most of the patients started to present strabismus since they were born. The most frequent perinatal risk factors were threatened miscarriage, pre-eclampsia, foetal distress, and hypoxia. Esotropia is the most common type of strabismus in psychomotor retardation. The variability of squint magnitude is a characteristic in these patients. The moderate variability is the most frequent in both esotropia and exotropia. The most common refractive error is hyperopic astigmatism in esotropia and the myopic kind in exotropia. Copyright © 2015 Academia Mexicana de Cirugía A.C. Published by Masson Doyma México S.A. All rights reserved.

  16. Full-scale demonstration. Fire testing of a system for penetration sealing based on foamed silicone elastomer: Studsvik 77-05-26

    International Nuclear Information System (INIS)

    Brown, A.

    1978-06-01

    Testing of a system for making fire retardant penetration seals based on foamed-in-place silicone elastomer is described. The report covers - Concept of fire retardant penetration seals and the Chemtrol system, Design FC 225 - Account of materials used to prepare seals and method of application - Test assembly and full-scale facility at Studsvik - Classification of seals used in demonstration - Diagrams of seals and photographs taken after demonstration

  17. Full-scale demonstration. Fire testing of a system for penetration sealing based on foamed silicone elastomer: Studsvik 77-05-26

    International Nuclear Information System (INIS)

    Brown, A.

    1978-06-01

    Testing of a system for making fire retardant penetration seals based on foamed-in-place silicone elastomer is described. The report covers - Concept of fire retardant penetration seals and the Chemtrol system, Design FC 225 - Account of materials used to prepare seals and method of application - Test assembly and full-scale facility at Studsvik - Classification of seals used in demonstration - Diagrams of seals and photographs taken after demonstration (author)

  18. Use of Mass Spectrometry for Identification of Biomarkers of Exposure to the Flame Retardant DI(2-Ethylhexyl)-2,3,4,5-Tetrabromophthlate

    Science.gov (United States)

    Di-(2-ethylhexyl)-2,3,4,5-tetrabromophthalate (TBPH) is one component in the technical formulation of Firemaster 550, a fire retardant used after phasing out certain polybrominated diphenyl ethers. Firemaster 550 is used widely and its use may result in human exposure to TBPH. To...

  19. Fire Behavior (FB)

    Science.gov (United States)

    Robert E. Keane

    2006-01-01

    The Fire Behavior (FB) method is used to describe the behavior of the fire and the ambient weather and fuel conditions that influence the fire behavior. Fire behavior methods are not plot based and are collected by fire event and time-date. In general, the fire behavior data are used to interpret the fire effects documented in the plot-level sampling. Unlike the other...

  20. Fire Symfonier

    DEFF Research Database (Denmark)

    Nielsen, Svend Hvidtfelt

    2009-01-01

    sidste fire symfonier. Den er måske snarere at opfatte som et præludium til disse. At påstå, at symfonierne fra Holmboes side er planlagt til at være beslægtede, ville være at gå for vidt. Alene de 26 år, der skiller den 10. fra den 13., gør påstanden - i bedste fald - dubiøs. Når deres udformning...... udkrystallisering som i de sidste små 30 år af hans virke har afkastet disse fire variationer over en grundlæggende central holmboesk fornemmelse for form, melodi, klang og rytme. Denne oplevelse har fået mig til at udforske symfonierne, for at finde til bunds i dette holmboeske fællestræk, som jeg mener her står...

  1. General chemistry

    International Nuclear Information System (INIS)

    Kwon, Yeong Sik; Lee, Dong Seop; Ryu, Haung Ryong; Jang, Cheol Hyeon; Choi, Bong Jong; Choi, Sang Won

    1993-07-01

    The book concentrates on the latest general chemistry, which is divided int twenty-three chapters. It deals with basic conception and stoichiometry, nature of gas, structure of atoms, quantum mechanics, symbol and structure of an electron of ion and molecule, chemical thermodynamics, nature of solid, change of state and liquid, properties of solution, chemical equilibrium, solution and acid-base, equilibrium of aqueous solution, electrochemistry, chemical reaction speed, molecule spectroscopy, hydrogen, oxygen and water, metallic atom; 1A, IIA, IIIA, carbon and atom IVA, nonmetal atom and an inert gas, transition metals, lanthanons, and actinoids, nuclear properties and radioactivity, biochemistry and environment chemistry.

  2. Radiation chemistry

    International Nuclear Information System (INIS)

    Swallow, A.J.

    1983-01-01

    The subject is covered in chapters, entitled: introduction (defines scope of article as dealing with the chemistry of reactive species, (e.g. excess electrons, excited states, free radicals and inorganic ions in unusual valency states) as studied using radiation with radiation chemistry in its traditional sense and with biological and industrial applications); gases; water and simple inorganic systems; aqueous metallo-organic compounds and metalloproteins; small organic molecules in aqueous solution; microheterogeneous systems; non-aqueous liquids and solutions; solids; biological macromolecules; synthetic polymers. (U.K.)

  3. Indoor Chemistry

    DEFF Research Database (Denmark)

    Weschler, Charles J.; Carslaw, Nicola

    2018-01-01

    This review aims to encapsulate the importance, ubiquity, and complexity of indoor chemistry. We discuss the many sources of indoor air pollutants and summarize their chemical reactions in the air and on surfaces. We also summarize some of the known impacts of human occupants, who act as sources...... and sinks of indoor chemicals, and whose activities (e.g., cooking, cleaning, smoking) can lead to extremely high pollutant concentrations. As we begin to use increasingly sensitive and selective instrumentation indoors, we are learning more about chemistry in this relatively understudied environment....

  4. Handbook of heterocyclic chemistry

    National Research Council Canada - National Science Library

    Katritzky, Alan R

    2010-01-01

    ... Heterocyclic Chemistry I (1984) Comprehensive Heterocyclic Chemistry II (1996) Comprehensive Heterocyclic Chemistry III (2008) Comprehensive Organic Functional Group Transformations I (1995) Compreh...

  5. Reinventing Chemistry

    OpenAIRE

    Whitesides, George McClelland

    2015-01-01

    Chemistry is in a period of change, from an era focused on molecules and reactions, to one in which manipulations of systems of molecules and reactions will be essential parts of controlling larger systems. This Essay traces paths from the past to possible futures.

  6. Chemistry Notes

    Science.gov (United States)

    School Science Review, 1972

    1972-01-01

    Short articles on the kinetics of the hydrogen peroxide-iodide ion reaction, simulation of fluidization catalysis, the use of Newman projection diagrams to represent steric relationships in organic chemistry, the use of synthetic substrates for proteolytic enzyme reactions, and two simple clock reactions"--hydrolysis of halogenoalkanes and…

  7. Browns Ferry fire

    International Nuclear Information System (INIS)

    Harkleroad, J.R.

    1983-01-01

    A synopsis of the March 22, 1975 fire at Browns Ferry Nuclear Plant is discussed. Emphasis is placed on events prior to and during the fire. How the fire started, fire fighting activities, fire and smoke development, and restoration activities are discussed

  8. Aluminium trihydroxide in combination with ammonium polyphosphate as flame retardants for unsaturated polyester resin

    Directory of Open Access Journals (Sweden)

    2009-11-01

    Full Text Available The thermal and reaction to fire characteristics of a flame retardant unsaturated polyester (UP ternary system are presented here. Thermal gravimetric analysis showed an improved thermal stability between 200–600°C with the addition of ammonium polyphosphate (APP and aluminium trihydroxide (ATH formulation. Cone calorimetry tests indicated that ATH is more efficient than calcium carbonate at delaying the ignition time, lowering the carbon monoxide yield and lowering the peak heat release (PHRR. However the addition of APP and ATH to the formulation failed to demonstrate any significant synergistic effect at reducing the PHRR.

  9. Brominated flame retardants and endocrine disruption

    NARCIS (Netherlands)

    Vos, J.G.; Becher, G.; Berg, van den M.; Boer, de J.; Leonards, P.E.G.

    2003-01-01

    From an environmental point of view, an increasing important group of organohalogen compounds are the brominated flame retardants (BFRs), which are widely used in polymers and textiles and applied in construction materials, furniture, and electronic equipment. BFRs with the highest production volume

  10. Brominated flame retardants and endocrine disruption

    NARCIS (Netherlands)

    Vos, Joseph G.; Becher, Georg; Van Den Berg, Martin; Leonards, Pim E G

    2003-01-01

    From an environmental point of view, an increasing important group of organo-halogen compounds are the brominated flame retardants (BFRs), which are widely used in polymers and textiles and applied in construction materials, furniture, and electronic equipment. BFRs with the highest production

  11. Retarded hippocampal development following prenatal exposure to ...

    African Journals Online (AJOL)

    Results: Rats in Group A showed no implantation, rats in Group B had abortion on the 7th day after administration, and rats in Group C gave birth with their litters showing retarded hippocampus development and neural degeneration and rats in Group D (control) showed normal development. Conclusion: Ethanolic extract of ...

  12. International Directory of Mental Retardation Resources.

    Science.gov (United States)

    Dybwad, Rosemary F., Ed.

    The directory lists and describes governmental and voluntary agencies, research, and other resources in the field of mental retardation in foreign countries. The first section, on international organizations, gives names, addresses, names of directors, and one or more paragraphs of description for the United Nations and its specialized agencies,…

  13. Improving Outcomes for Workers with Mental Retardation

    Science.gov (United States)

    Fornes, Sandra; Rocco, Tonette S.; Rosenberg, Howard

    2008-01-01

    This research presents an analysis of factors predicting job retention, job satisfaction, and job performance of workers with mental retardation. The findings highlight self-determination as a critical skill in predicting the three important employee outcomes. The study examined a hypothesized job retention model and the outcome of the three…

  14. Euthanasia and Mental Retardation: Suggesting the Unthinkable.

    Science.gov (United States)

    Hollander, Russell

    1989-01-01

    The article examines current opinions toward euthanasia of persons with mental retardation in light of the history of public and professional attitudes. It also discusses the rejection of euthanasia on moral and religious grounds, and notes the use of lifelong incarceration, based on eugenics principles, to accomplish similar ends. (DB)

  15. Opitz C syndrome: Trigonocephaly, mental retardation and ...

    African Journals Online (AJOL)

    We describe a 4-year-old female child with a dysmorphic and neurological syndrome of trigonocephaly, mental and psychomotor retardation and dysmorphic facial ... The patient had important cerebral anomalies with diffuse alterations in white matter that caused developmental delay with verbal and nonverbal disabilities ...

  16. Puberty in the Girl Who is Retarded.

    Science.gov (United States)

    Pattullo, Ann

    Designed to help mothers of mentally retarded girls deal with the problems and concerns of puberty, the booklet provides information on physical and emotional changes, menstruation, masturbation, heterosexual behavior, contraception, protection against sexual aggression, the possibilities of marriage, and additional sources of information.…

  17. Skin mastocytosis, hearing loss and mental retardation

    NARCIS (Netherlands)

    Hennekam, R. C.; Beemer, F. A.

    1992-01-01

    A girl with skin mastocytosis, hearing loss, microcephaly, mild dysmorphic features and severe mental retardation is described. The symptoms of the child resemble those reported in 1990 by Wolach et al. in another patient sufficiently to suspect the same entity in both. Inheritance may be autosomal

  18. Computer Needs of Severely Mentally Retarded Persons.

    Science.gov (United States)

    Flanagan, Kelly

    1982-01-01

    The article reviews technology applicable for use by severely mentally retarded learners. Descriptions are given of assistive devices (including communication aids), controls and interfaces (such as single switch access to standard software), and software (including games to teach cause and effect and simple matching and counting). (CL)

  19. Preparation of Flame Retardant Modified with Titanate for Asphalt Binder

    Directory of Open Access Journals (Sweden)

    Bo Li

    2014-01-01

    Full Text Available Improving the compatibility between flame retardant and asphalt is a difficult task due to the complex nature of the materials. This study explores a low dosage compound flame retardant and seeks to improve the compatibility between flame retardants and asphalt. An orthogonal experiment was designed taking magnesium hydroxide, ammonium polyphosphate, and melamine as factors. The oil absorption and activation index were tested to determine the effect of titanate on the flame retardant additive. The pavement performance test was conducted to evaluate the effect of the flame retardant additive. Oxygen index test was conducted to confirm the effect of flame retardant on flame ability of asphalt binder. The results of this study showed that the new composite flame retardant is more effective in improving the compatibility between flame retardant and asphalt and reducing the limiting oxygen index of asphalt binder tested in this study.

  20. Nonretarded and Mentally Retarded Children's Control over Syntax Structures.

    Science.gov (United States)

    McLeavey, Breda C.; And Others

    1982-01-01

    Ten nonretarded preschoolers and 10 mildly mentally retarded children (mean age 8 years) were compared for control over various syntactic structures. The retarded children evidenced difficulties similar to those of younger nonretarded children. (Author/SB)

  1. Fire Ant Bites

    Science.gov (United States)

    ... Favorite Name: Category: Share: Yes No, Keep Private Fire Ant Bites Share | Fire ants are aggressive, venomous insects that have pinching ... across the United States, even into Puerto Rico. Fire ant stings usually occur on the feet or ...

  2. Fire safety at home

    Science.gov (United States)

    ... over the smoke alarm as needed. Using a fire extinguisher can put out a small fire to keep it from getting out of control. Tips for use include: Keep fire extinguishers in handy locations, at least one on ...

  3. Crown Fire Potential

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — Crown fire potential was modeled using FlamMap, an interagency fire behavior mapping and analysis program that computes potential fire behavior characteristics. The...

  4. National Fire Protection Association

    Science.gov (United States)

    ... closed NFPA Journal® NFPA Journal® Update (newsletter) Fire Technology ... die from American home fires, and another 13,000 are injured each year. This is the story of fire that the statistics won't show ...

  5. Chemistry and physics

    International Nuclear Information System (INIS)

    Broerse, J.J.; Barendsen, G.W.; Kal, H.B.; Kogel, A.J. van der

    1983-01-01

    This book contains the extended abstracts of the contributions of the poster workshop sessions on chemistry and physics of the 7th international congress of radiation research. They cover the following main topics: primary processes in radiation physics and chemistry, general chemistry in radiation chemistry, DNA and model systems in radiation chemistry, molecules of biological interest in radiation chemistry, techniques in radiation chemistry, hot atom chemistry. refs.; figs.; tabs

  6. Fine chemistry

    International Nuclear Information System (INIS)

    Laszlo, P.

    1988-01-01

    The 1988 progress report of the Fine Chemistry laboratory (Polytechnic School, France) is presented. The research programs are centered on the renewal of the organic chemistry most important reactions and on the invention of new, highly efficient and highly selective reactions, by applying low cost reagents and solvents. An important research domain concerns the study and fabrication of new catalysts. They are obtained by means of the reactive sputtering of the metals and metal oxydes thin films. The Monte Carlo simulations of the long-range electrostatic interaction in a clay and the obtention of acrylamides from anhydrous or acrylic ester are summarized. Moreover, the results obtained in the field of catalysis are also given. The published papers and the congress communications are included [fr

  7. Effectiveness of Flame Retardants in TufFoam.

    Energy Technology Data Exchange (ETDEWEB)

    Abelow, Alexis Elizabeth [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Nissen, April [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Massey, Lee Taylor [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Whinnery, LeRoy L. [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2017-12-01

    An investigation of polyurethane foam filled with known flame retardant fillers including hydroxides, melamine, phosphate-containing compounds, and melamine phosphates was carried out to produce a low-cost material with high flame retardant efficiency. The impact of flame retardant fillers on the physical properties such a s composite foam density, glass transition temperature, storage modulus, and thermal expansion of composite foams was investigated with the goal of synthesizing a robust rigid foam with excellent flame retardant properties.

  8. Radioanalytical chemistry

    International Nuclear Information System (INIS)

    1982-01-01

    The bibliography of Hungarian literature in the field of radioanalytical chemistry covers the four-year period 1976-1979. The list of papers contains 290 references in the alphabetical order of the first authors. The majority of the titles belongs to neutron activation analysis, labelling, separation and determination of radioactive isotopes. Other important fields like radioimmunoassay, environmental protection etc. are covered as well. (Sz.J.)

  9. Analytical chemistry

    International Nuclear Information System (INIS)

    Anon.

    1985-01-01

    The division for Analytical Chemistry continued to try and develope an accurate method for the separation of trace amounts from mixtures which, contain various other elements. Ion exchange chromatography is of special importance in this regard. New separation techniques were tried on certain trace amounts in South African standard rock materials and special ceramics. Methods were also tested for the separation of carrier-free radioisotopes from irradiated cyclotron discs

  10. Containment Sodium Chemistry Models in MELCOR.

    Energy Technology Data Exchange (ETDEWEB)

    Louie, David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Humphries, Larry L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Denman, Matthew R [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-04-01

    To meet regulatory needs for sodium fast reactors’ future development, including licensing requirements, Sandia National Laboratories is modernizing MELCOR, a severe accident analysis computer code developed for the U.S. Nuclear Regulatory Commission (NRC). Specifically, Sandia is modernizing MELCOR to include the capability to model sodium reactors. However, Sandia’s modernization effort primarily focuses on the containment response aspects of the sodium reactor accidents. Sandia began modernizing MELCOR in 2013 to allow a sodium coolant, rather than water, for conventional light water reactors. In the past three years, Sandia has been implementing the sodium chemistry containment models in CONTAIN-LMR, a legacy NRC code, into MELCOR. These chemistry models include spray fire, pool fire and atmosphere chemistry models. Only the first two chemistry models have been implemented though it is intended to implement all these models into MELCOR. A new package called “NAC” has been created to manage the sodium chemistry model more efficiently. In 2017 Sandia began validating the implemented models in MELCOR by simulating available experiments. The CONTAIN-LMR sodium models include sodium atmosphere chemistry and sodium-concrete interaction models. This paper presents sodium property models, the implemented models, implementation issues, and a path towards validation against existing experimental data.

  11. Industrial chemistry engineering

    International Nuclear Information System (INIS)

    1993-01-01

    This book on industrial chemistry engineering is divided in two parts. The first part deals with industrial chemistry, inorganic industrial chemistry, organic industrial chemistry, analytical chemistry and practical questions. The last parts explain the chemical industry, a unit parts and thermodynamics in chemical industry and reference. It reveals the test subjects for the industrial chemistry engineering with a written examination and practical skill.

  12. Computational chemistry

    Science.gov (United States)

    Arnold, J. O.

    1987-01-01

    With the advent of supercomputers, modern computational chemistry algorithms and codes, a powerful tool was created to help fill NASA's continuing need for information on the properties of matter in hostile or unusual environments. Computational resources provided under the National Aerodynamics Simulator (NAS) program were a cornerstone for recent advancements in this field. Properties of gases, materials, and their interactions can be determined from solutions of the governing equations. In the case of gases, for example, radiative transition probabilites per particle, bond-dissociation energies, and rates of simple chemical reactions can be determined computationally as reliably as from experiment. The data are proving to be quite valuable in providing inputs to real-gas flow simulation codes used to compute aerothermodynamic loads on NASA's aeroassist orbital transfer vehicles and a host of problems related to the National Aerospace Plane Program. Although more approximate, similar solutions can be obtained for ensembles of atoms simulating small particles of materials with and without the presence of gases. Computational chemistry has application in studying catalysis, properties of polymers, all of interest to various NASA missions, including those previously mentioned. In addition to discussing these applications of computational chemistry within NASA, the governing equations and the need for supercomputers for their solution is outlined.

  13. Green chemistry

    International Nuclear Information System (INIS)

    Warner, John C.; Cannon, Amy S.; Dye, Kevin M.

    2004-01-01

    A grand challenge facing government, industry, and academia in the relationship of our technological society to the environment is reinventing the use of materials. To address this challenge, collaboration from an interdisciplinary group of stakeholders will be necessary. Traditionally, the approach to risk management of materials and chemicals has been through inerventions intended to reduce exposure to materials that are hazardous to health and the environment. In 1990, the Pollution Prevention Act encouraged a new tact-elimination of hazards at the source. An emerging approach to this grand challenge seeks to embed the diverse set of environmental perspectives and interests in the everyday practice of the people most responsible for using and creating new materials--chemists. The approach, which has come to be known as Green Chemistry, intends to eliminate intrinsic hazard itself, rather than focusing on reducing risk by minimizing exposure. This chapter addresses the representation of downstream environmental stakeholder interests in the upstream everyday practice that is reinventing chemistry and its material inputs, products, and waste as described in the '12 Principles of Green Chemistry'

  14. Flame retardancy and thermal degradation of cotton textiles based on UV-curable flame retardant coatings

    Energy Technology Data Exchange (ETDEWEB)

    Xing, Weiyi [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzai Road, Hefei, Anhui 230026 (China); Suzhou Institute for Advanced Study, University of Science and Technology of China, 166 Ren' ai Road, Suzhou, Jiangsu 215123 (China); Jie, Ganxin [State Key Laboratory of Environmental Adaptability for Industrial Products, China National Electric Apparatus Research Institute, Guangzhou 510300 (China); Song, Lei; Hu, Shuang; Lv, Xiaoqi; Wang, Xin [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzai Road, Hefei, Anhui 230026 (China); Hu, Yuan, E-mail: yuanhu@ustc.edu.cn [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzai Road, Hefei, Anhui 230026 (China); Suzhou Institute for Advanced Study, University of Science and Technology of China, 166 Ren' ai Road, Suzhou, Jiangsu 215123 (China)

    2011-01-20

    The flame retardant coatings were prepared through UV-curable technique using tri(acryloyloxyethyl) phosphate (TAEP) and triglycidyl isocyanurate acrylate (TGICA). Results from FTIR-ATR spectroscopy and scanning electron microscopy (SEM) showed that flame retardant coatings were successfully coated onto the surface of cotton fabrics. The flame retardancy of the treated fabrics was studied by Micro-scale Combustion Calorimeter (MCC) and limited oxygen index (LOI). The cottons coated flame retardant coatings had the lower peak heat release rate (PHRR), heat release capacity (HRC), total heat of combustion (THC) and higher LOI value compared with untreated cotton. The results from TGA test showed that the flame retardant coatings lowered the decomposition temperature of treated fabric. The thermal decomposition of cottons was monitored by real time FTIR analysis and thermogravimetric analysis/infrared spectrometry (TGA-IR). The enhanced flame retardant action might be caused by thermal decomposition of TAEP structure, producing acidic intermediates, which could react with fabrics to alter its thermal decomposition process.

  15. Caring for children with mental retardation: The experiences of ...

    African Journals Online (AJOL)

    Caring for children with mental retardation at home requires great patience and understanding. Mothers often experience difficulties adjusting to the fact that their children are mentally retarded and that it cannot be cured. This study investigated the experiences of mothers caring for children with mental retardation.

  16. Anxious-retarded depression: relation to family history of depression

    NARCIS (Netherlands)

    de Winter, Remco F. P.; Zwinderman, Koos H.; Goekoop, Jaap G.

    2004-01-01

    Anxious-retarded depression is a two-dimensionally defined subcategory of depression based on high scores for both anxiety and retardation. The anxious-retarded subcategory is related to melancholia as defined by DSM-IV. Patients with this diagnosis exhibit elevated plasma arginine vasopressin (AVP)

  17. FIRE CHARACTERISTICS FOR ADVANCED MODELLING OF FIRES

    OpenAIRE

    Otto Dvořák

    2016-01-01

    This paper summarizes the material and fire properties of solid flammable/combustible materials /substances /products, which are used as inputs for the computer numerical fire models. At the same time it gives the test standards for their determination.

  18. Challenges to fire protection measures at Hamaoka Nuclear Power Station

    International Nuclear Information System (INIS)

    Narama, Takeshi

    2015-01-01

    New regulatory standards for fire protection at nuclear power plants have been established by the Nuclear Regulation Authority. This paper introduces the measures taken by the Hamaoka Nuclear Power Station for the following four items, which were especially big changes. (1) To install a combination of sensors of different types or instruments with equivalent functions so as to be able to emit unique signals to inform a fire in the early stage. (2) To conduct 'UL vertical burn test' as the demonstration test for self-extinguishing performance as the condition for flame-retardant cable. (3) To install automatic fire-extinguishers or fixed fire-extinguishing devices of manual type at the spots where fire-fighting is difficult due to the filling of smoke in a fire or the effect of radiation. (4) To separate the system for purpose of ensuring safety function to attain the high-temperature shutdown and cold-temperature shutdown of a reactor whatever fire may happen at the nuclear facilities. The examples of the installation of fire-extinguishers as the measures for the above Item (3) are as follows; (A) as for the devices containing oil, a foam-extinguishing agent is released against each target device from the nozzle, and (B) for large vertical pump motors indoors and relatively small pump motors, IA type automatic foam extinguishing systems are installed. (A.O.)

  19. Fire and fire ecology: Concepts and principles

    Science.gov (United States)

    Mark A. Cochrane; Kevin C. Ryan

    2009-01-01

    Fire has been central to terrestrial life ever since early anaerobic microorganisms poisoned the atmosphere with oxygen and multicellular plant life moved onto land. The combination of fuels, oxygen, and heat gave birth to fire on Earth. Fire is not just another evolutionary challenge that life needed to overcome, it is, in fact, a core ecological process across much...

  20. The status and challenge of global fire modelling

    Science.gov (United States)

    Hantson, Stijn; Arneth, Almut; Harrison, Sandy P.; Kelley, Douglas I.; Prentice, I. Colin; Rabin, Sam S.; Archibald, Sally; Mouillot, Florent; Arnold, Steve R.; Artaxo, Paulo; Bachelet, Dominique; Ciais, Philippe; Forrest, Matthew; Friedlingstein, Pierre; Hickler, Thomas; Kaplan, Jed O.; Kloster, Silvia; Knorr, Wolfgang; Lasslop, Gitta; Li, Fang; Mangeon, Stephane; Melton, Joe R.; Meyn, Andrea; Sitch, Stephen; Spessa, Allan; van der Werf, Guido R.; Voulgarakis, Apostolos; Yue, Chao

    2016-06-01

    Biomass burning impacts vegetation dynamics, biogeochemical cycling, atmospheric chemistry, and climate, with sometimes deleterious socio-economic impacts. Under future climate projections it is often expected that the risk of wildfires will increase. Our ability to predict the magnitude and geographic pattern of future fire impacts rests on our ability to model fire regimes, using either well-founded empirical relationships or process-based models with good predictive skill. While a large variety of models exist today, it is still unclear which type of model or degree of complexity is required to model fire adequately at regional to global scales. This is the central question underpinning the creation of the Fire Model Intercomparison Project (FireMIP), an international initiative to compare and evaluate existing global fire models against benchmark data sets for present-day and historical conditions. In this paper we review how fires have been represented in fire-enabled dynamic global vegetation models (DGVMs) and give an overview of the current state of the art in fire-regime modelling. We indicate which challenges still remain in global fire modelling and stress the need for a comprehensive model evaluation and outline what lessons may be learned from FireMIP.

  1. Dual protection of wood surface treated with melamine-modified urea-formaldehyde resin mixed with ammonium polyphosphate against both fire and decay

    Science.gov (United States)

    Xing-xia Ma; Grant T. Kirker; Ming-liang Jiang; Yu-zhang Wu

    2016-01-01

    Surface coatings of melamine-modified urea-formaldehyde resins (MUFs) containing ammonium polyphosphate (APP) have been shown to significantly improve the fire retardancy of wood by prolonging the ignition time and reducing the heat release rate, total heat released, and mass loss rate. Dual protection of wood against both decay and fire has been proposed for remedial...

  2. Theoretical chemistry periodicities in chemistry and biology

    CERN Document Server

    Eyring, Henry

    1978-01-01

    Theoretical Chemistry: Periodicities in Chemistry and Biology, Volume 4 covers the aspects of theoretical chemistry. The book discusses the stably rotating patterns of reaction and diffusion; the chemistry of inorganic systems exhibiting nonmonotonic behavior; and population cycles. The text also describes the mathematical modeling of excitable media in neurobiology and chemistry; oscillating enzyme reactions; and oscillatory properties and excitability of the heart cell membrane. Selected topics from the theory of physico-chemical instabilities are also encompassed. Chemists, mechanical engin

  3. THE SYNERGISTIC EFFECT OF HYBRID FLAME RETARDANTS ON PYROLYSIS BEHAVIOUR OF HYBRID COMPOSITE MATERIALS

    Directory of Open Access Journals (Sweden)

    M. T. ALBDIRY

    2012-06-01

    Full Text Available The aim of this investigation is to comprehensively understand the polymeric composite behavior under direct fire sources. The synergistic effects of hybrid flame retardant material on inhabiting the pyrolysis of hybrid reinforced fibers, woven roving (0°- 45° carbon and kevlar (50/50 wt/wt, and an araldite resin composites were studied. The composites were synthesised and coated primarily by zinc borate (2ZnO.3B2O3.3.5H2O and modified by antimony trioxide (Sb2O3 with different amounts (10-30 wt% of flame retardant materials. In the experiments, the composite samples were exposed to a direct flame source generated by oxyacetylene flame (~3000ºC at variable exposure distances of 10-20 mm. The synergic flame retardants role of antimony trioxide and zinc borate on the composite surface noticeably improves the flame resistance of the composite which is attributed to forming a protective mass and heat barrier on the composite surface and increasing the melt viscosity.

  4. Dust-Firing of Straw and Additives

    DEFF Research Database (Denmark)

    Wu, Hao; Glarborg, Peter; Frandsen, Flemming

    2011-01-01

    In the present work, the ash chemistry and deposition behavior during straw dust-firing were studied by performing experiments in an entrained flow reactor. The effect of using spent bleaching earth (SBE) as an additive in straw combustion was also investigated by comparing with kaolinite. During...... dust-firing of straw, the large (>∼2.5 μm) fly ash particles generated were primarily molten or partially molten spherical particles rich in K, Si, and Ca, supplemented by Si-rich flake-shaped particles. The smaller fly ash particles (...

  5. Solution chemistry

    Energy Technology Data Exchange (ETDEWEB)

    None

    1973-07-01

    Research progress is reported on studies in heavy element chemistry. Topics considered are: synergistic complexes of plutonyl ion; water uptake in synergistic systems; formation constants of some uranyl BETA -diketone complexes; thermodynamic acid dissociation constants of BETA -diketones; thermodynamic formation constants of uranyl BETA -diketonates; thiocyanate complexes of some trivalent lanthanides and actinides; stability constants of actinide complexes using dinonyl naphthalenesulfonic acid extraction; TBP extraction of actinides; stability constants of complexes of Pu(III) with 5- sulfosalicycllc acid; and solvent extraction behavior of Pu( VII). (DHM)

  6. Interstellar chemistry.

    Science.gov (United States)

    Klemperer, William

    2006-08-15

    In the past half century, radioastronomy has changed our perception and understanding of the universe. In this issue of PNAS, the molecular chemistry directly observed within the galaxy is discussed. For the most part, the description of the molecular transformations requires specific kinetic schemes rather than chemical thermodynamics. Ionization of the very abundant molecular hydrogen and atomic helium followed by their secondary reactions is discussed. The rich variety of organic species observed is a challenge for complete understanding. The role and nature of reactions involving grain surfaces as well as new spectroscopic observations of interstellar and circumstellar regions are topics presented in this special feature.

  7. Interpersonal Communication of Children with Mental Retardation

    Directory of Open Access Journals (Sweden)

    Aliyah Nur'aini Hanun

    2013-11-01

    Full Text Available Tunagrahita were a terminology to called the children with mentally retarded conditions. This conditions caused these children having difficulties at least on four areas, related with attention, memory, language, and academics. The research problem is how interpersonal communication tunagrahita in Dormitory Extraordinary Education Foundation (YPLB Cipaganti Bandung. This research’s aim is to seek the interpersonal communication phenomenon of children with mentally retarded in YPLB Cipaganti Dormitory. The research method which were used is the qualitative method with communication Ethnography approach and Symbolic Interactionism theory to have comprehensive descriptions about life reality of mentally retarded’s children in YPLB Cipaganti Dormitory. Data obtained by participation observer, unstructured interviews, and documentary study. The result showed that interpersonal interactions are done with each child boarding and with the management of the hostel, is a series of unique events and interpersonal communication with a distinctive circular process that takes place continuously.

  8. Psychomotor Retardation in untreated depressed elderly

    Directory of Open Access Journals (Sweden)

    Lieve Lia Beheydt

    2015-01-01

    Full Text Available Background: Psychomotor retardation (PR is one of the core features in depression according to 17 DSM V1, but also aging in itself causes cognitive and psychomotor slowing. This is the first study 18 investigating psychomotor retardation in relation to cognitive functioning and to the concomitant 19 effect of depression and aging in a geriatric population ruling out contending effects of psychotropic 20 medication. Methods: A group of 28 non-demented depressed elderly is compared to a matched 21 control group of 20 healthy elderly. All participants underwent a test battery containing clinical 22 depression measures, cognitive measures of processing speed, executive function and memory, 23 clinical ratings of psychomotor retardation and objective computerized fine motor skill-tests. 24 Statistical analysis consisted of a General Linear Method (GLM multivariate analysis of variance to 25 compare the clinical, cognitive and psychomotor outcomes of the two groups. Results: Patients 26 performed worse on all clinical, cognitive and psychomotor retardation measures. Both groups 27 showed an effect of cognitive load on fine motor function but the influence was significantly larger 28 for patients than for healthy elderly except for the initiation time. Limitations: due to the restrictive 29 inclusion criteria, only a relatively limited sample size could be obtained. Conclusion: With a 30 medication free sample, an additive effect of depression and aging on cognition and PR in geriatric 31 patients was found,. As this effect was independent of demand of effort (by varying the cognitive 32 load, it was apparently not a motivational slowing effect of depression.

  9. Oral Rehabilitation and Management of Mentally Retarded

    OpenAIRE

    Solanki, Jitender; Khetan, Jitendra; Gupta, Sarika; Tomar, Deepak; Singh, Meenakshi

    2015-01-01

    High level of periodontal problems of dental caries are frequently observed in mentally handicapped children. This group of patients presents various problems when they face dental treatments. Identification of such population and providing them affordable oral health care is the new concept. A systematic method for identification and screening of persons with mental retardation has been developed and is being followed. Cost and fear are the most commonly cited barriers to dental care. Physic...

  10. Inherited retarded eruption in the permanent dentition.

    Science.gov (United States)

    Rasmussen, P; Kotsaki, A

    1997-01-01

    The term retarded eruption, may be used in cases where eruption is inhibited, causing an interruption in the coordination of tooth formation and tooth eruption. The phenomenon may be local or general, and several etiological factors for retarded eruption have been listed, comprising a lack of space, ankylosis, cysts, supernumerary teeth, hormone and vitamin deficiencies and several developmental disturbances and syndromes. The present paper describes several cases of retarded eruption where no factors other than inheritance have been evident. So far 14 cases have been evaluated, 9 boys and 5 girls. In addition several cases have been registered among parents and grandparents of the probands. Typical features are: retarded eruption, defined as more than 3 SD beyond mean eruption figures, comprises all teeth in the permanent dentition, and in 5 cases also second primary molars. The chronology of tooth formation are within normal limits. Consequently the teeth finish development still laying deeply buried in the jaws, often in aberrant positions and with curves or hooks on the roots. When the teeth finally get the "signal" for eruption, 5-15 years beyond normal eruption time, they move rather quickly into right positions, despite the long eruption paths and the hooked roots. Permanent teeth without, as well as with predecessors, are affected. Extraction of predecessors does not seem to provoke eruption. The main features in management are to take care of the primary teeth, to improve-esthetics, and offer surgery and orthodontics when needed. Analyses of pedigrees indicates that the genetic transmittance may be autosomal dominant as both sexes are affected, about half of the siblings show the trait, and the trait shows continuity through generations.

  11. Fires, ecological effects of

    Science.gov (United States)

    W. J. Bond; Robert Keane

    2017-01-01

    Fire is both a natural and anthropogenic disturbance influencing the distribution, structure, and functioning of terrestrial ecosystems around the world. Many plants and animals depend on fire for their continued existence. Others species, such as rainforest plants species, are extremely intolerant of burning and need protection from fire. The properties of a fire...

  12. Fears of institutionalized mentally retarded adults.

    Science.gov (United States)

    Sternlicht, M

    1979-01-01

    The patterns of fears of institutionalized mentally retarded adults were studied in a sample of i2 moderately retarded men and women between the ages of 21-49. The direct questioning method was employed. Two interviews were held, two weeks apart; the first interview elicited the Ss' fears, while the second concerned the fears of their friends. A total of 146 responses were obtained, and these were categorized according to the types of fears: supernatural-natural events, animals, physical injury, psychological stress, egocentric responses, and no fears. The Ss displayed a higher percentage of fears in the preoperational stage than in the concrete operational stage. In a comparison of male to female fears, only one category, that of fears of animals, reached significance. The study suggested that the same developmental trend of fears that appears in normal children appears in the retarded as well, and these fears follow Piaget's level of cognitive development, proceeding from egocentric perceptions of causality to realistic cause and effect thinking.

  13. Flame Retardant Polyamide Fibres: The Challenge of Minimising Flame Retardant Additive Contents with Added Nanoclays

    Directory of Open Access Journals (Sweden)

    Richard Horrocks

    2016-08-01

    Full Text Available This work shows that halogen-free, flame retarded polyamide 6 (PA6, fabrics may be produced in which component fibres still have acceptable tensile properties and low levels (preferably ≤10 wt % of additives by incorporating a nanoclay along with two types of flame retardant formulations. The latter include (i aluminium diethyl phosphinate (AlPi at 10 wt %, known to work principally in the vapour phase and (ii ammonium sulphamate (AS/dipentaerythritol (DP system present at 2.5 and 1 wt % respectively, believed to be condense phase active. The nanoclay chosen is an organically modified montmorillonite clay, Cloisite 25A. The effect of each additive system is analysed in terms of its ability to maximise both filament tensile properties relative to 100% PA6 and flame retardant behaviour of knitted fabrics in a vertical orientation. None of the AlPi-containing formulations achieved self-extinguishability, although the presence of nanoclay promoted lower burning and melt dripping rates. The AS/DP-containing formulations with total flame retardant levels of 5.5 wt % or less showed far superior properties and with nanoclay, showed fabric extinction times ≤ 39 s and reduced melt dripping. The tensile and flammability results, supported by thermogravimetric analysis, have been interpreted in terms of the mechanism of action of each flame retardant/nanoclay type.

  14. Multi-functional carbon microspheres with double shell layers for flame retardant poly (ethylene terephthalate)

    Science.gov (United States)

    Xue, Baoxia; Niu, Mei; Yang, Yongzhen; Bai, Jie; Song, Yinghao; Peng, Yun; Liu, Xuguang

    2018-03-01

    Carbon microspheres (CMSs) as a core material had been coated by two capsule walls: an inorganic material of magnesium hydroxide (MH) as inner shell layer and an organic material of poly (ethylene terephthalate) (PET) as outer shell layer. MH coating CMSs (MCMSs) were fabricated by liquid phase deposition method, then grafted 3-Aminopropyltriethoxysilane (APTS) to obtain the Si-MCMSs. Microencapsulated Si-MCMSs (PMCMSs) was prepared by in situ polymerization method. Morphology structure, dispersion, flame retardant and other properties of PMCMSs have been investigated. A series of PET blends were prepared by melt compounding. The results showed that MH and PET as two layers were coated on CMSs surface with the optimal thickness of about 70 nm. The PMCMSs owned better dispersion in PET matrix. Compared with MCMSs/PET composites, the mechanical property of PMCMSs/PET composites had significantly increased because of the strong interface binding force between PMCMSs and PET matrix. Moreover, PMCMSs was proved to be an effective flame retardant. For PMCMSs/PET with 2 wt% PMCMSs, the limiting oxygen index (LOI) value increased from 21.0% (pristine PET) to 27.2%, and the peak heat release rate (pk-HRR) decreased from 513.22 kW/m2 to 352.14 kW/m2. The decreased smoke production rate (SPR) and total smoke production (TSP) values demonstrated PMCMSs suppressed the smoke production. The increased Fire performance index (FPI) value illustrated PMCMSs significantly reduced the fire risk of PET. Overall, the two capsular walls endowed the PMCMSs/PET composites with good mechanical and flame-retardant properties.

  15. Thermal Stability, Combustion Behavior, and Mechanical Property in a Flame-Retardant Polypropylene System

    Directory of Open Access Journals (Sweden)

    Lili Wang

    2017-01-01

    Full Text Available In order to comprehensively improve the strength, toughness, flame retardancy, smoke suppression, and thermal stability of polypropylene (PP, layered double hydroxide (LDH Ni0.2Mg2.8Al–LDH was synthesized by a coprecipitation method coupled with the microwave-hydrothermal treatment. The X-ray diffraction (XRD, morphology, mechanical, thermal, and fire properties for PP composites containing 1 wt %–20 wt % Ni0.2Mg2.8Al–LDH were investigated. The cone calorimeter tests confirm that the peak heat release rate (pk–HRR of PP–20%LDH was decreased to 500 kW/m2 from the 1057 kW/m2 of PP. The pk–HRR, average mass loss rate (AMLR and effective heat of combustion (EHC analysis indicates that the condensed phase fire retardant mechanism of Ni0.2Mg2.8Al–LDH in the composites. The production rate and mean release yield of CO for composites gradually decrease as Ni0.2Mg2.8Al–LDH increases in the PP matrix. Thermal analysis indicates that the decomposition temperature for PP–5%LDH and PP–10%LDH is 34 °C higher than that of the pure PP. The mechanical tests reveal that the tensile strength of PP–1%LDH is 7.9 MPa higher than that of the pure PP. Furthermore, the elongation at break of PP–10%LDH is 361% higher than PP. In this work, the synthetic LDH Ni0.2Mg2.8Al–LDH can be used as a flame retardant, smoke suppressant, thermal stabilizer, reinforcing, and toughening agent of PP products.

  16. Radiation chemistry and bioradical chemistry

    International Nuclear Information System (INIS)

    Ferradini, C.

    1991-01-01

    Oxygen metabolism results, at the cellular level, in the formation of superoxyde radical O 2 - · and probably also of hydroxyl radical OH·. Other radical species can be produced from exogenous or endogenous molecules and nearly all of them have the possibility to react with oxygen giving peroxyradicals. Some of these transients play a role in various biological processes such as phagocytosis, inflammation or ischemy although the mechanisms invoked are poorly understood. Radiation chemistry is an invaluable tool for obtaining a quantitative view of these mechanisms. A description is given of this interaction [fr

  17. Fire in Fennoscandia: A palaeo-perspective of spatial and temporal variability in fire frequency and vegetation dynamics

    Science.gov (United States)

    Clear, Jennifer; Bradshaw, Richard; Seppä, Heikki

    2014-05-01

    Active fire suppression in Fennoscandia has created a boreal forest ecosystem that is almost free of fire. Absence of fire is thought to have contributed to the widespread dominance of Picea abies (Norway spruce), though the character and structure of spruce forests operates as a positive feedback retarding fire frequency. This lack of fire and dominance by Picea abies may have assisted declines in deciduous tree species, with a concomitant loss of floristic diversity. Forest fires are driven by a complex interplay between natural (climate, vegetation and topography) and anthropogenic disturbance and through palaeoecology we are able to explore spatio-temporal variability in the drivers of fire, changing fire dynamics and the subsequent consequences for forest succession, development and floristic diversity over long timescales. High resolution analysis of palaeoenvironmental proxies (pollen and macroscopic charcoal) allows Holocene vegetation and fire dynamics to be reconstructed at the local forest-stand scale. Comparisons of fire histories with pollen-derived quantitative reconstruction of vegetation at local- and regional-scales identify large-scale ecosystem responses and local-scale disturbance. Spatio-temporal heterogeneity and variability in biomass burning is explored to identify the drivers of fire and palaeovegetation reconstructions are compared to process-based, climate-driven dynamic vegetation model output to test the significance of fire frequency as a driver of vegetation composition and dynamics. Fire was not always so infrequent in the northern European forest with early-Holocene fire regimes driven by natural climate variations and fuel availability. The establishment and spread of Picea abies was probably driven by an increase in continentality of climate, but local natural and anthropogenic ecosystem disturbance may have aided this spread. Picea expansion led to a step-wise reduction in regional biomass burning and here we show the now

  18. Building 431 fire tests

    International Nuclear Information System (INIS)

    Alvares, N.J.; Beason, D.G.; Ford, H.W.; Magee, M.W.

    1977-01-01

    An extensive discussion of considerations for fire protection in the LLL mirror fusion test facility (MFTF) is presented. Because of the large volume and high bays of the building, sufficient data on fire detection is unavailable. Results of fire detection tests using controlled fire sources in the building are presented. Extensive data concerning the behavior of the building atmosphere are included. Candidate fire detection instrumentation and extinguishing systems for use in the building are briefly reviewed

  19. Fire-Walking

    Science.gov (United States)

    Willey, David

    2010-01-01

    This article gives a brief history of fire-walking and then deals with the physics behind fire-walking. The author has performed approximately 50 fire-walks, took the data for the world's hottest fire-walk and was, at one time, a world record holder for the longest fire-walk (www.dwilley.com/HDATLTW/Record_Making_Firewalks.html). He currently…

  20. Fire, safety and ventilation

    Energy Technology Data Exchange (ETDEWEB)

    Hindle, D.

    1999-02-01

    Correct ventilation in tunnel environments is vital for the comfort and safety of the people passing through. This article gives details of products from several manufacturers of safety rescue and fire fighting equipment, fire and fume detection equipment, special fire resistant materials, fire resistant hydraulic oils and fire dampers, and ventilation systems. Company addresses and fax numbers are supplied. 4 refs., 5 tabs., 10 photos.

  1. Flame retardancy mechanisms of bisphenol A bis(diphenyl phosphate) in combination with zinc borate in bisphenol A polycarbonate/acrylonitrile-butadiene-styrene blends

    International Nuclear Information System (INIS)

    Pawlowski, Kristin H.; Schartel, Bernhard; Fichera, Mario A.; Jaeger, Christian

    2010-01-01

    Bisphenol A polycarbonate/acrylonitrile-butadiene-styrene (PC/ABS) with and without bisphenol A bis(diphenyl phosphate) (BDP) and 5 wt.% zinc borate (Znb) were investigated. The pyrolysis was studied by thermogravimetry (TG), TG-FTIR and NMR, the fire behaviour with a cone calorimeter applying different heat fluxes, LOI and UL 94. Fire residues were examined with NMR. BDP affects the decomposition of PC/ABS and acts as a flame retardant in the gas and condensed phases. The addition of Znb results in an additional hydrolysis of PC. The fire behaviour is similar to PC/ABS, aside from a slightly increased LOI and a reduced peak heat release rate, both caused by borates improving the barrier properties of the char. In PC/ABS + BDP + Znb, the addition of Znb yields a borate network and amorphous phosphates. Znb also reacts with BDP to form alpha-zinc phosphate and borophosphates that suppress the original flame retardancy mechanisms of BDP. The inorganic-organic residue formed provides more effective flame retardancy, in particular at low irradiation in the cone calorimeter, and a clear synergy in LOI, whereas for more developed fires BDP + Znb become less effective than BDP in PC/ABS with respect to the total heat evolved.

  2. Fundamentals of nuclear chemistry

    International Nuclear Information System (INIS)

    Majer, K.

    1982-01-01

    The textbook is a Czech-to-German translation of the second revised edition and covers the subject under the headings: general nuclear chemistry, methods of nuclear chemistry, preparative nuclear chemistry, analytical nuclear chemistry, and applied chemistry. The book is especially directed to students

  3. Atmospheric Chemistry Over Southern Africa

    Science.gov (United States)

    Gatebe, Charles K.; Levy, Robert C.; Thompson, Anne M.

    2011-01-01

    During the southern African dry season, regional haze from mixed industrial pollution, biomass burning aerosol and gases from domestic and grassland fires, and biogenic sources from plants and soils is worsened by a semi-permanent atmosphere gyre over the subcontinent. These factors were a driver of several major international field campaigns in the 1990s and early 2000s, and attracted many scientists to the region. Some researchers were interested in understanding fundamental processes governing chemistry of the atmosphere and interaction with climate change. Others found favorable conditions for evaluating satellite-derived measurements of atmospheric properties and a changing land surface. With that background in mind a workshop on atmospheric chemistry was held in South Africa. Sponsored by the International Commission for Atmospheric Chemistry and Global Pollution (ICACGP; http://www.icacgp.org/), the workshop received generous support from the South African power utility, Eskom, and the Climatology Research Group of the University of the Witwatersrand, Johannesburg, South Africa. The purpose of the workshop was to review some earlier findings as well as more recent findings on southern African climate vulnerability, chemical changes due to urbanization, land-use modification, and how these factors interact. Originally proposed by John Burrows, president of ICACGP, the workshop was the first ICACGP regional workshop to study the interaction of air pollution with global chemical and climate change. Organized locally by the University of the Witwatersrand, the workshop attracted more than 60 delegates from South Africa, Mozambique, Botswana, Zimbabwe, France, Germany, Canada, and the United States. More than 30 presentations were given, exploring both retrospective and prospective aspects of the science. In several talks, attention was focused on southern African chemistry, atmospheric pollution monitoring, and climate processes as they were studied in the field

  4. Associations between brominated flame retardants in house dust and hormone levels in men

    International Nuclear Information System (INIS)

    Johnson, Paula I.; Stapleton, Heather M.; Mukherjee, Bhramar; Hauser, Russ; Meeker, John D.

    2013-01-01

    Brominated flame retardants (BFRs) are used in the manufacture of a variety of materials and consumer products in order to meet fire safety standards. BFRs may persist in the environment and have been detected in wildlife, humans and indoor dust and air. Some BFRs have demonstrated endocrine and reproductive effects in animals, but human studies are limited. In this exploratory study, we measured serum hormone levels and flame retardant concentrations [31 polybrominated diphenyl ether (PBDE) congeners and 6 alternate flame retardants] in house dust from men recruited through a US infertility clinic. PBDE congeners in dust were grouped by commercial mixtures (i.e. penta-, octa- and deca-BDE). In multivariable linear regression models adjusted by age and body mass index (BMI), significant positive associations were found between house dust concentrations of pentaBDEs and serum levels of free T4, total T3, estradiol, and sex hormone binding globulin (SHBG), along with an inverse association with follicle stimulating hormone (FSH). There were also positive associations of octaBDE concentrations with serum free T4, thyroid stimulating hormone (TSH), luteinizing hormone (LH) and testosterone and an inverse association of decaBDE concentrations with testosterone. Hexabromocyclododecane (HBCD) was associated with decreased SHBG and increased free androgen index. Dust concentrations of bis-tribromophenoxyethane (BTBPE) and tetrabromo-diethylhexylphthalate (TBPH) were positively associated with total T3. These findings are consistent with our previous report of associations between PBDEs (BDE 47, 99 and 100) in house dust and hormone levels in men, and further suggest that exposure to contaminants in indoor dust may be leading to endocrine disruption in men. - Highlights: ► Brominated flame retardants (BFRs) including PBDEs and alternates were measured. ► Exposure to BFRs is characterized from concentrations in participant vacuum bag dust. ► Exposure to PBDEs and

  5. Associations between brominated flame retardants in house dust and hormone levels in men

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Paula I. [Department of Environmental Health Sciences, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109 (United States); Stapleton, Heather M. [Nicholas School of the Environment, Box 90328, Duke University, Durham, NC 27708 (United States); Mukherjee, Bhramar [Department of Biostatistics, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109 (United States); Hauser, Russ [Department of Environmental Health, Harvard School of Public Health, 677 Huntington Ave., Boston, MA 02115 (United States); Meeker, John D., E-mail: meekerj@umich.edu [Department of Environmental Health Sciences, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109 (United States)

    2013-02-15

    Brominated flame retardants (BFRs) are used in the manufacture of a variety of materials and consumer products in order to meet fire safety standards. BFRs may persist in the environment and have been detected in wildlife, humans and indoor dust and air. Some BFRs have demonstrated endocrine and reproductive effects in animals, but human studies are limited. In this exploratory study, we measured serum hormone levels and flame retardant concentrations [31 polybrominated diphenyl ether (PBDE) congeners and 6 alternate flame retardants] in house dust from men recruited through a US infertility clinic. PBDE congeners in dust were grouped by commercial mixtures (i.e. penta-, octa- and deca-BDE). In multivariable linear regression models adjusted by age and body mass index (BMI), significant positive associations were found between house dust concentrations of pentaBDEs and serum levels of free T4, total T3, estradiol, and sex hormone binding globulin (SHBG), along with an inverse association with follicle stimulating hormone (FSH). There were also positive associations of octaBDE concentrations with serum free T4, thyroid stimulating hormone (TSH), luteinizing hormone (LH) and testosterone and an inverse association of decaBDE concentrations with testosterone. Hexabromocyclododecane (HBCD) was associated with decreased SHBG and increased free androgen index. Dust concentrations of bis-tribromophenoxyethane (BTBPE) and tetrabromo-diethylhexylphthalate (TBPH) were positively associated with total T3. These findings are consistent with our previous report of associations between PBDEs (BDE 47, 99 and 100) in house dust and hormone levels in men, and further suggest that exposure to contaminants in indoor dust may be leading to endocrine disruption in men. - Highlights: ► Brominated flame retardants (BFRs) including PBDEs and alternates were measured. ► Exposure to BFRs is characterized from concentrations in participant vacuum bag dust. ► Exposure to PBDEs and

  6. Aerosols from fires: an examination of the effects on ozone photochemistry in the Western United States.

    Science.gov (United States)

    Jiang, Xiaoyan; Wiedinmyer, Christine; Carlton, Annmarie G

    2012-11-06

    This study presents a first attempt to investigate the roles of fire aerosols in ozone (O(3)) photochemistry using an online coupled meteorology-chemistry model, the Weather Research and Foresting model with Chemistry (WRF-Chem). Four 1-month WRF-Chem simulations for August 2007, with and without fire emissions, were carried out to assess the sensitivity of O(3) predictions to the emissions and subsequent radiative feedbacks associated with large-scale fires in the Western United States (U.S.). Results show that decreases in planetary boundary layer height (PBLH) resulting from the radiative effects of fire aerosols and increases in emissions of nitrogen oxides (NO(x)) and volatile organic compounds (VOCs) from the fires tend to increase modeled O(3) concentrations near the source. Reductions in downward shortwave radiation reaching the surface and surface temperature due to fire aerosols cause decreases in biogenic isoprene emissions and J(NO(2)) photolysis rates, resulting in reductions in O(3) concentrations by as much as 15%. Thus, the results presented in this study imply that considering the radiative effects of fire aerosols may reduce O(3) overestimation by traditional photochemical models that do not consider fire-induced changes in meteorology; implementation of coupled meteorology-chemistry models are required to simulate the atmospheric chemistry impacted by large-scale fires.

  7. Emerging contaminants related to the occurrence of forest fires in the Spanish Mediterranean

    NARCIS (Netherlands)

    Campo, J.; Lorenzo, M.; Cammeraat, E.L.H.; Picó, Y.; Andreu, V.

    2017-01-01

    Forest fires can be a source of contamination because, among others, of the use of chemicals to their extinction (flame retardants, FRs), or by the production of Polycyclic Aromatic Hydrocarbons (PAHs) derived from high temperature alteration of organic matter. Up to our knowledge, this study is the

  8. Cyclodextrin chemistry

    International Nuclear Information System (INIS)

    Khan, M.Z.; Chuaqui, C.A.

    1990-05-01

    The chemistry of cyclodextrins was studied. This study included synthesising some cyclodextrin derivatives, preparing selected inclusion complexes with cyclodextrin and investigating the effects of gamma irradiation on cyclodextrins and certain linear oligosaccharides. This report presents a brief review of the structure and properties of cyclodextrins, the synthesis of cyclodextrin derivatives, their complexation and applications. This is followed by a description of the synthesis of some cyclodextrin derivatives and the preparation of inclusion complexes of cyclodextrin with some organic compounds. Finally, the effects of gamma irradiation on cyclodextrins, some of their derivatives and certain structurally related carbohydrates are discussed. The gamma irradiation studies were carried out for two reasons: to study the effects of gamma irradiation on cyclodextrins and their derivatives; and to investigate selectivity during the gamma irradiation of cyclodextrin derivatives

  9. Astronomical chemistry.

    Science.gov (United States)

    Klemperer, William

    2011-01-01

    The discovery of polar polyatomic molecules in higher-density regions of the interstellar medium by means of their rotational emission detected by radioastronomy has changed our conception of the universe from essentially atomic to highly molecular. We discuss models for molecule formation, emphasizing the general lack of thermodynamic equilibrium. Detailed chemical kinetics is needed to understand molecule formation as well as destruction. Ion molecule reactions appear to be an important class for the generally low temperatures of the interstellar medium. The need for the intrinsically high-quality factor of rotational transitions to definitively pin down molecular emitters has been well established by radioastronomy. The observation of abundant molecular ions both positive and, as recently observed, negative provides benchmarks for chemical kinetic schemes. Of considerable importance in guiding our understanding of astronomical chemistry is the fact that the larger molecules (with more than five atoms) are all organic.

  10. Reburning chemistry

    International Nuclear Information System (INIS)

    Kilpin, P.; Hupa, M.; Glarborg, P.

    1992-01-01

    No reduction chemistry in natural gas (methane) reburning was studied using detailed kinetic modeling. A reaction set including 225 reversible elementary gas-phase reactions and 48 chemical species was applied to an ideal plug flow reactor, and the most important reactions leading to NO reduction were identified and quantified for a number of conditions relevant for natural gas reburning. In addition, the influence of different process parameters on the NO reduction was investigated in the reburn zone and burn-out zone, respectively. Further, comparison of the calculations to available laboratory-scale data on reburning is made. In this paper, the impact of various fluid dynamic, mixing, and chemical effects---not accounted for in the calculations---on the NO reduction and the optimum reburning conditions predicted is discussed

  11. Combustion chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Brown, N.J. [Lawrence Berkeley Laboratory, CA (United States)

    1993-12-01

    This research is concerned with the development and use of sensitivity analysis tools to probe the response of dependent variables to model input variables. Sensitivity analysis is important at all levels of combustion modeling. This group`s research continues to be focused on elucidating the interrelationship between features in the underlying potential energy surface (obtained from ab initio quantum chemistry calculations) and their responses in the quantum dynamics, e.g., reactive transition probabilities, cross sections, and thermal rate coefficients. The goals of this research are: (i) to provide feedback information to quantum chemists in their potential surface refinement efforts, and (ii) to gain a better understanding of how various regions in the potential influence the dynamics. These investigations are carried out with the methodology of quantum functional sensitivity analysis (QFSA).

  12. FIRES: Fire Information Retrieval and Evaluation System - A program for fire danger rating analysis

    Science.gov (United States)

    Patricia L. Andrews; Larry S. Bradshaw

    1997-01-01

    A computer program, FIRES: Fire Information Retrieval and Evaluation System, provides methods for evaluating the performance of fire danger rating indexes. The relationship between fire danger indexes and historical fire occurrence and size is examined through logistic regression and percentiles. Historical seasonal trends of fire danger and fire occurrence can be...

  13. New tendencies in wildland fire simulation for understanding fire phenomena: An overview of the WFDS system capabilities in Mediterranean ecosystems

    Science.gov (United States)

    Pastor, E.; Tarragó, D.; Planas, E.

    2012-04-01

    Wildfire theoretical modeling endeavors predicting fire behavior characteristics, such as the rate of spread, the flames geometry and the energy released by the fire front by applying the physics and the chemistry laws that govern fire phenomena. Its ultimate aim is to help fire managers to improve fire prevention and suppression and hence reducing damage to population and protecting ecosystems. WFDS is a 3D computational fluid dynamics (CFD) model of a fire-driven flow. It is particularly appropriate for predicting the fire behaviour burning through the wildland-urban interface, since it is able to predict the fire behaviour in the intermix of vegetative and structural fuels that comprise the wildland urban interface. This model is not suitable for operational fire management yet due to computational costs constrains, but given the fact that it is open-source and that it has a detailed description of the fuels and of the combustion and heat transfer mechanisms it is currently a suitable system for research purposes. In this paper we present the most important characteristics of the WFDS simulation tool in terms of the models implemented, the input information required and the outputs that the simulator gives useful for understanding fire phenomena. We briefly discuss its advantages and opportunities through some simulation exercises of Mediterranean ecosystems.

  14. Why Teach Environmental Chemistry?

    Science.gov (United States)

    Gardner, Marjorie H.

    1974-01-01

    Discusses the importance of teaching environmental chemistry in secondary school science classes, and outlines five examples of environmental chemistry problems that focus on major concepts of chemistry and have critical implications for human survival and well-being. (JR)

  15. Environmental chemistry. Seventh edition

    Energy Technology Data Exchange (ETDEWEB)

    Manahan, S.E. [Univ. of Missouri, Columbia, MO (United States)

    1999-11-01

    This book presents a basic understanding of environmental chemistry and its applications. In addition to providing updated materials in this field, the book emphasizes the major concepts essential to the practice of environmental chemistry. Topics of discussion include the following: toxicological chemistry; toxicological chemistry of chemical substances; chemical analysis of water and wastewater; chemical analysis of wastes and solids; air and gas analysis; chemical analysis of biological materials and xenobiotics; fundamentals of chemistry; and fundamentals of organic chemistry.

  16. Retardo del crecimiento intrauterino Intrauterine growth retardation

    Directory of Open Access Journals (Sweden)

    Adriana Cuartas Calle

    1995-01-01

    Full Text Available

    El crecimiento fetal anormal es un aspecto de gran interés en la obstetricia actual y un dilema clínico relativamente frecuente. La falla del crecimiento sigue siendo un enigma a pesar de los adelantos que ha habido en su conocimiento: el diagnóstico temprano y preciso del retardo del crecimiento puede aminorar la incidencia de complicaciones y muerte en fetos con este problema. Por ello es necesario mejorar las técnicas para identificar esta entidad y asegurar una atención apropiada durante el embarazo y el parto. En este artículo se resumen datos acerca de la definición del retardo del crecimiento fetal, su fisiopatología, clasificación, etiología, diagnóstico y manejo.

    Abnormal fetal growth is a very important aspect In present-day obstetrics and a frequent clinical dilemma. Fetal failure to grow continues to be puzzling, despite advances in its knowledge; early and precise diagnosis of growth retardation can diminish the incidence of complications and death of fetuses with this problem. It becomes therefore necessary, in the presence of growth retardation, to improve diagnostic techniques and assure proper attention during pregnancy and delivery. Information is summarized in this review on the definition, pathophysiology, classification, etiology, diagnosis and handling of fetal growth retardation.

  17. USSR Report Chemistry

    National Research Council Canada - National Science Library

    1986-01-01

    Contents: Adsorption, Chemistry,Alkaloids, Analytical Chemistry, Catalysis,Chemical Industry,,Coal Gasification, Combustion, Electrochemistry,Explosives and Explosions, Fertilizers, Free Radicals, Inorganic...

  18. Investigation of pressure retarded osmosis power production

    Directory of Open Access Journals (Sweden)

    Taousanidis Nikolaos

    2017-01-01

    Full Text Available A major source of energy exists where there is mixing between aqueous solutions of different salinities. This energy source is particularly concentrated where fresh water rivers flow on to the ocean. The power, represented by the osmotic pressure difference between fresh water and salt water, may be called salinity gradient power. In this study the pressure retarded osmosis method for the extraction of salinity gradients’ energy is investigated, main problems and difficulties are pointed out and finally the whole subject is justified with experimental results.

  19. Effect of Dricon® in Kenaf Core Particleboard Towards On Fire Performance

    OpenAIRE

    Mohamad Jani Saad; Zaihan Jalaludin; Izran Kamal

    2011-01-01

    One layer kenaf core particleboard was treated with one of the advanced fire retardants, Dricon® . The percentage of 8 % (w/w) and 12 % (w/w) of Dricon® were incorporated into three different board densities (350 kg/m3, 450 kg/m3 and 550 kg/m3) which were fabricated with three resin loadings (w/w) of urea formaldehyde (8%, 10% and 12%). Each of treated and untreated particleboard has been tested with blow torch and fire propagation tests. The fire propagation test was evaluated by using perfo...

  20. Characteristics of Those Persons with Mental Retardation Registered with the Mental Retardation Division.

    Science.gov (United States)

    Cocks, Errol; Ng, Pin Chee

    1983-01-01

    The paper discusses an analysis of a computerized data bank on the mentally retarded population in Victoria, Australia. Prevalence rates, severity of handicap, age, sex, and residence type are reviewed and implications for community vocational and residential services for adults are noted. (CL)

  1. Distal joint contractures, mental retardation, characteristic face and growth retardation: Chitayat syndrome revisited.

    NARCIS (Netherlands)

    Wortmann, S.B.; Rodenburg, R.J.T.; Schwahn, B.; Smeitink, J.A.M.; Morava, E.

    2007-01-01

    We report on a patient with congenital distal limb contractures, characteristic face, prominent metopic sutures, narrow forehead, severe psychomotor and growth retardation, white matter lesions and failure to thrive. The child has many overlapping features with those reported previously by Chitayat.

  2. Dysmorphology and mental retardation: molecular cytogenetic studies in dysmorphic mentally retarded patients.

    NARCIS (Netherlands)

    Buggenhout, G.J.C.M. van; Ravenswaaij-Arts, C.M.A. van; Mieloo, H.; Syrrou, M.; Hamel, B.C.J.; Brunner, H.G.; Fryns, J.P.

    2001-01-01

    In an institutionalised population of 471 mentally retarded adult residents (436 males and 35 females), 18 patients (16 males and 2 females) with dysmorphic features were selected to perform FISH studies by using subtelomeric probes to discover cryptic terminal deletions or duplications,

  3. Water chemistry

    International Nuclear Information System (INIS)

    Hofstetter, K.J.; Baston, V.F.

    1986-01-01

    Prior to the accident, the coolants in the primary and secondary systems were within normal chemistry specifications for an operating pressurized water reactor with once-through steam generators. During and immediately after the accident, additional boric acid and sodium hydroxide were added to the primary coolant for control of criticality and radioiodine solubility. A primary to secondary leak developed contaminating the water in one steam generator. For about 5 years after the accident, the primary coolant was maintained at 3800 +. 100 ppm boron and 1000 +. 100 ppm sodium concentrations. Dissolved oxygen was maintained 7.5, corrosion caused by increased dissolved oxygen levels (up to 8 ppm) and higher chloride ion content (up to 5 ppm) is minimized. Chemical control of dissolved oxygen was discontinued and the coolant was processed. Prior to removal of the reactor vessel head, the boron concentration in the coolant was increased to ≅ 5000 ppm to support future defueling operations. Decontamination of the accident generated water is described in terms of contaminated water management. In addition, the decontamination and chemical lay-up conditions for the secondary system are presented along with an overview of chemical management at TMI-2

  4. Migration chemistry

    International Nuclear Information System (INIS)

    Carlsen, L.

    1992-05-01

    Migration chemistry, the influence of chemical -, biochemical - and physico-chemical reactions on the migration behaviour of pollutants in the environment, is an interplay between the actual natur of the pollutant and the characteristics of the environment, such as pH, redox conditions and organic matter content. The wide selection of possible pollutants in combination with varying geological media, as well as the operation of different chemical -, biochemical - and physico-chemical reactions compleactes the prediction of the influence of these processes on the mobility of pollutants. The report summarizes a wide range of potential pollutants in the terrestrial environment as well as a variety of chemical -, biochemical - and physico-chemical reactions, which can be expected to influence the migration behaviour, comprising diffusion, dispersion, convection, sorption/desorption, precipitation/dissolution, transformations/degradations, biochemical reactions and complex formation. The latter comprises the complexation of metal ions as well as non-polar organics to naturally occurring organic macromolecules. The influence of the single types of processes on the migration process is elucidated based on theoretical studies. The influence of chemical -, biochemical - and physico-chemical reactions on the migration behaviour is unambiguous, as the processes apparently control the transport of pollutants in the terrestrial environment. As the simple, conventional K D concept breaks down, it is suggested that the migration process should be described in terms of the alternative concepts chemical dispersion, average-elution-time and effective retention. (AB) (134 refs.)

  5. Forest fire forecasting tool for air quality modelling systems

    International Nuclear Information System (INIS)

    San Jose, R.; Perez, J. L.; Perez, L.; Gonzalez, R. M.; Pecci, J.; Palacios, M.

    2015-01-01

    Adverse effects of smoke on air quality are of great concern; however, even today the estimates of atmospheric fire emissions are a key issue. It is necessary to implement systems for predicting smoke into an air quality modelling system, and in this work a first attempt towards creating a system of this type is presented. Wild land fire spread and behavior are complex phenomena due to both the number of involved physic-chemical factors, and the nonlinear relationship between variables. WRF-Fire was employed to simulate spread and behavior of some real fires occurred in South-East of Spain and North of Portugal. The use of fire behavior models requires the availability of high resolution environmental and fuel data. A new custom fuel moisture content model has been developed. The new module allows each time step to calculate the fuel moisture content of the dead fuels and live fuels. The results confirm that the use of accurate meteorological data and a custom fuel moisture content model is crucial to obtain precise simulations of fire behavior. To simulate air pollution over Europe, we use the regional meteorological-chemistry transport model WRF-Chem. In this contribution, we show the impact of using two different fire emissions inventories (FINN and IS4FIRES) and how the coupled WRF-Fire- Chem model improves the results of the forest fire emissions and smoke concentrations. The impact of the forest fire emissions on concentrations is evident, and it is quite clear from these simulations that the choice of emission inventory is very important. We conclude that using the WRF-fire behavior model produces better results than using forest fire emission inventories although the requested computational power is much higher. (Author)

  6. Forest fire forecasting tool for air quality modelling systems

    Energy Technology Data Exchange (ETDEWEB)

    San Jose, R.; Perez, J.L.; Perez, L.; Gonzalez, R.M.; Pecci, J.; Palacios, M.

    2015-07-01

    Adverse effects of smoke on air quality are of great concern; however, even today the estimates of atmospheric fire emissions are a key issue. It is necessary to implement systems for predicting smoke into an air quality modelling system, and in this work a first attempt towards creating a system of this type is presented. Wildland fire spread and behavior are complex Phenomena due to both the number of involved physic-chemical factors, and the nonlinear relationship between variables. WRF-Fire was employed to simulate spread and behavior of some real fires occurred in South-East of Spain and North of Portugal. The use of fire behavior models requires the availability of high resolution environmental and fuel data. A new custom fuel moisture content model has been developed. The new module allows each time step to calculate the fuel moisture content of the dead fuels and live fuels. The results confirm that the use of accurate meteorological data and a custom fuel moisture content model is crucial to obtain precise simulations of fire behavior. To simulate air pollution over Europe, we use the regional meteorological-chemistry transport model WRF-Chem. In this contribution, we show the impact of using two different fire emissions inventories (FINN and IS4FIRES) and how the coupled WRF-FireChem model improves the results of the forest fire emissions and smoke concentrations. The impact of the forest fire emissions on concentrations is evident, and it is quite clear from these simulations that the choice of emission inventory is very important. We conclude that using the WRF-fire behavior model produces better results than using forest fire emission inventories although the requested computational power is much higher. (Author)

  7. Forest fire forecasting tool for air quality modelling systems

    Energy Technology Data Exchange (ETDEWEB)

    San Jose, R.; Perez, J. L.; Perez, L.; Gonzalez, R. M.; Pecci, J.; Palacios, M.

    2015-07-01

    Adverse effects of smoke on air quality are of great concern; however, even today the estimates of atmospheric fire emissions are a key issue. It is necessary to implement systems for predicting smoke into an air quality modelling system, and in this work a first attempt towards creating a system of this type is presented. Wild land fire spread and behavior are complex phenomena due to both the number of involved physic-chemical factors, and the nonlinear relationship between variables. WRF-Fire was employed to simulate spread and behavior of some real fires occurred in South-East of Spain and North of Portugal. The use of fire behavior models requires the availability of high resolution environmental and fuel data. A new custom fuel moisture content model has been developed. The new module allows each time step to calculate the fuel moisture content of the dead fuels and live fuels. The results confirm that the use of accurate meteorological data and a custom fuel moisture content model is crucial to obtain precise simulations of fire behavior. To simulate air pollution over Europe, we use the regional meteorological-chemistry transport model WRF-Chem. In this contribution, we show the impact of using two different fire emissions inventories (FINN and IS4FIRES) and how the coupled WRF-Fire- Chem model improves the results of the forest fire emissions and smoke concentrations. The impact of the forest fire emissions on concentrations is evident, and it is quite clear from these simulations that the choice of emission inventory is very important. We conclude that using the WRF-fire behavior model produces better results than using forest fire emission inventories although the requested computational power is much higher. (Author)

  8. Crack retardation by load reduction during fatigue crack propagation

    International Nuclear Information System (INIS)

    Kim, Hyun Soo; Nam, Ki Woo; Ahn, Seok Hwan; Do, Jae Yoon

    2003-01-01

    Fracture life and crack retardation behavior were examined experimentally using CT specimens of aluminum alloy 5083. Crack retardation life and fracture life were a wide difference between 0.8 and 0.6 in proportion to ratio of load reduction. The wheeler model retardation parameter was used successfully to predict crack growth behavior. By using a crack propagation rule, prediction of fracture life can be evaluated quantitatively. A statistical approach based on Weibull distribution was applied to the test data to evaluate the dispersion in the retardation life and fracture life by the change of load reduction

  9. Wildland fire in ecosystems: effects of fire on flora

    Science.gov (United States)

    James K. Brown; Jane Kapler Smith

    2000-01-01

    VOLUME 2: This state-of-knowledge review about the effects of fire on flora and fuels can assist land managers with ecosystem and fire management planning and in their efforts to inform others about the ecological role of fire. Chapter topics include fire regime classification, autecological effects of fire, fire regime characteristics and postfire plant community...

  10. A review of fire interactions and mass fires

    Science.gov (United States)

    Mark A. Finney; Sara S. McAllister

    2011-01-01

    The character of a wildland fire can change dramatically in the presence of another nearby fire. Understanding and predicting the changes in behavior due to fire-fire interactions cannot only be life-saving to those on the ground, but also be used to better control a prescribed fire to meet objectives. In discontinuous fuel types, such interactions may elicit fire...

  11. POLYAMIDE 6 WITH A FLAME RETARDANT ENCAPSULATED BY POLYAMIDE 66: FLAME RETARDATION, THERMO-DECOMPOSITION AND THE POTENTIAL MECHANISM

    Institute of Scientific and Technical Information of China (English)

    Wei-cheng Xiong; Li Chen; Bin Zhao; De-yi Wang; Yu-zhong Wang

    2012-01-01

    A novel encapsulated flame retardant containing phosphorus-nitrogen (MSMM-Al-P) was prepared by encapsulating with polyamide 66 (PA66-MSMM-Al-P) for the flame retardation of polyamide 6 (PA6).The structure and thermal properties of PA66-MSMM-Al-P were characterized by Fourier-transform infrared spectroscopy,X-ray photoelectron spectroscopy and thermogravimetric analysis.The flammability of PA6 containing' flame retardants (MSMMAl-P and PA66-MSMM-Al-P) was investigated by the limiting oxygen index test,vertical burning test and cone calorimeter.The flame retardancy and cone calorimetric analyses suggested a synergistic effect between PA66 and MSMM-Al-P in the flame-retardant PA6.Thermal stability of the flame-retardant PA6 was also investigated.

  12. Potential human exposure to halogenated flame-retardants in elevated surface dust and floor dust in an academic environment

    International Nuclear Information System (INIS)

    Allgood, Jaime M.; Jimah, Tamara; McClaskey, Carolyn M.; La Guardia, Mark J.; Hammel, Stephanie C.; Zeineddine, Maryam M.; Tang, Ian W.; Runnerstrom, Miryha G.; Ogunseitan, Oladele A.

    2017-01-01

    Most households and workplaces all over the world possess furnishings and electronics, all of which contain potentially toxic flame retardant chemicals to prevent fire hazards. Indoor dust is a recognized repository of these types of chemicals including polybrominated diphenyl ethers (PBDEs) and non-polybrominated diphenyl ethers (non-PBDEs). However, no previous U.S. studies have differentiated concentrations from elevated surface dust (ESD) and floor dust (FD) within and across microenvironments. We address this information gap by measuring twenty-two flame-retardant chemicals in dust on elevated surfaces (ESD; n=10) and floors (FD; n=10) from rooms on a California campus that contain various concentrations of electronic products. We hypothesized a difference in chemical concentrations in ESD and FD. Secondarily, we examined whether or not this difference persisted: (a) across the studied microenvironments and (b) in rooms with various concentrations of electronics. A Wilcoxon signed-rank test demonstrated that the ESD was statistically significantly higher than FD for BDE-47 (p=0.01), BDE-99 (p=0.01), BDE-100 (p=0.01), BDE-153 (p=0.02), BDE-154 (p=0.02), and 3 non-PBDEs including EH-TBB (p=0.02), BEH-TEBP (p=0.05), and TDCIPP (p=0.03). These results suggest different levels and kinds of exposures to flame-retardant chemicals for individuals spending time in the sampled locations depending on the position of accumulated dust. Therefore, further research is needed to estimate human exposure to flame retardant chemicals based on how much time and where in the room individuals spend their time. Such sub-location estimates will likely differ from assessments that assume continuous unidimensional exposure, with implications for improved understanding of potential health impacts of flame retardant chemicals. - Highlights: • Brominated flame retardants used in electronic products accumulate in room dust • Various chemical moieties of flame retardants leach

  13. Potential human exposure to halogenated flame-retardants in elevated surface dust and floor dust in an academic environment

    Energy Technology Data Exchange (ETDEWEB)

    Allgood, Jaime M.; Jimah, Tamara [Department of Population Health & Disease Prevention, Program in Public Health, University of California, Irvine, CA 92697-3957 (United States); McClaskey, Carolyn M. [Department of Cognitive Sciences, School of Social Sciences, University of California, Irvine, CA 92697-5100 (United States); La Guardia, Mark J. [Department of Aquatic Health Sciences, Virginia Institute of Marine Science, College of William and Mary, Gloucester Point, VA 23062 (United States); Hammel, Stephanie C.; Zeineddine, Maryam M.; Tang, Ian W.; Runnerstrom, Miryha G. [Department of Population Health & Disease Prevention, Program in Public Health, University of California, Irvine, CA 92697-3957 (United States); Ogunseitan, Oladele A., E-mail: Oladele.Ogunseitan@uci.edu [Department of Population Health & Disease Prevention, Program in Public Health, University of California, Irvine, CA 92697-3957 (United States)

    2017-02-15

    Most households and workplaces all over the world possess furnishings and electronics, all of which contain potentially toxic flame retardant chemicals to prevent fire hazards. Indoor dust is a recognized repository of these types of chemicals including polybrominated diphenyl ethers (PBDEs) and non-polybrominated diphenyl ethers (non-PBDEs). However, no previous U.S. studies have differentiated concentrations from elevated surface dust (ESD) and floor dust (FD) within and across microenvironments. We address this information gap by measuring twenty-two flame-retardant chemicals in dust on elevated surfaces (ESD; n=10) and floors (FD; n=10) from rooms on a California campus that contain various concentrations of electronic products. We hypothesized a difference in chemical concentrations in ESD and FD. Secondarily, we examined whether or not this difference persisted: (a) across the studied microenvironments and (b) in rooms with various concentrations of electronics. A Wilcoxon signed-rank test demonstrated that the ESD was statistically significantly higher than FD for BDE-47 (p=0.01), BDE-99 (p=0.01), BDE-100 (p=0.01), BDE-153 (p=0.02), BDE-154 (p=0.02), and 3 non-PBDEs including EH-TBB (p=0.02), BEH-TEBP (p=0.05), and TDCIPP (p=0.03). These results suggest different levels and kinds of exposures to flame-retardant chemicals for individuals spending time in the sampled locations depending on the position of accumulated dust. Therefore, further research is needed to estimate human exposure to flame retardant chemicals based on how much time and where in the room individuals spend their time. Such sub-location estimates will likely differ from assessments that assume continuous unidimensional exposure, with implications for improved understanding of potential health impacts of flame retardant chemicals. - Highlights: • Brominated flame retardants used in electronic products accumulate in room dust • Various chemical moieties of flame retardants leach

  14. Social support of mentally retarded persons

    Directory of Open Access Journals (Sweden)

    Danuta Zwolinska

    2015-01-01

    Full Text Available Purpose: The aim of this work is to assess the relationship between the environment and mentally retarded persons. Material and methods: Information referring to social support of mentally retarded persons is a source material collected on the base of the data included in the Polish and foreign literature. The issues under discussion related to the following problems: social integration of persons with intellectual disabilities in a family and local environment, social functioning of people with mild intellectual disability, social rehabilitation of people with moderate, severe and profound intellectual disability and specific contact with people with disabilities. Results: For a person with an intellectual disability, the family is the source of acquisition of basic social skills that give him the opportunity for further development and performing certain social roles in a sense of safety. Full acceptance of the intellectually disabled, may dismiss their sense of shame and fear, and instill the satisfaction of belonging to a social community. Conclusions: Full social acceptance of people with intellectual disabilities is the basis for their assimilation and social functioning.

  15. Fires and Food Safety

    Science.gov (United States)

    ... Forms FSIS United States Department of Agriculture Food Safety and Inspection Service About FSIS District Offices Careers ... JSR 286) Actions ${title} Loading... Fires and Food Safety Fire! Few words can strike such terror. Residential ...

  16. Filosofiens historiografi: Fire genrer

    DEFF Research Database (Denmark)

    Rorty, Richard

    2007-01-01

    Oversættelse af Richard Rortys artikel "Filosofiens historiografi: Fire genrer" Udgivelsesdato: 26 Oktober......Oversættelse af Richard Rortys artikel "Filosofiens historiografi: Fire genrer" Udgivelsesdato: 26 Oktober...

  17. Tunnel fire dynamics

    CERN Document Server

    Ingason, Haukur; Lönnermark, Anders

    2015-01-01

    This book covers a wide range of issues in fire safety engineering in tunnels, describes the phenomena related to tunnel fire dynamics, presents state-of-the-art research, and gives detailed solutions to these major issues. Examples for calculations are provided. The aim is to significantly improve the understanding of fire safety engineering in tunnels. Chapters on fuel and ventilation control, combustion products, gas temperatures, heat fluxes, smoke stratification, visibility, tenability, design fire curves, heat release, fire suppression and detection, CFD modeling, and scaling techniques all equip readers to create their own fire safety plans for tunnels. This book should be purchased by any engineer or public official with responsibility for tunnels. It would also be of interest to many fire protection engineers as an application of evolving technical principles of fire safety.

  18. Fire Stations - 2007

    Data.gov (United States)

    Kansas Data Access and Support Center — Fire Station Locations in Kansas Any location where fire fighters are stationed at or based out of, or where equipment that such personnel use in carrying out their...

  19. Seerley Road Fire Site

    Science.gov (United States)

    A barn caught fire at on Seerley Road, Indianapolis. Five storage drums believed to contain metallic potassium were involved in the fire. EPA will perform additional sampling as part of removal operations and safe offsite transportation.

  20. Buildings exposed to fire

    International Nuclear Information System (INIS)

    1987-01-01

    The 24 lectures presented to the colloquium cover the following subject fields: (1) Behaviour of structural components exposed to fire; (2) Behaviour of building materials exposed to fire; (3) Thermal processes; (4) Safety related, theoretical studies. (PW) [de

  1. Interagency Wildland Fire Cooperation

    National Research Council Canada - National Science Library

    2004-01-01

    Wildlife Fire Assistance includes training personnel, forms partnerships for prescribed burns, state and regional data for fire management plans, develops agreements for DoD civilians to be reimbursed...

  2. Spacecraft Fire Safety Demonstration

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of the Spacecraft Fire Safety Demonstration project is to develop and conduct large-scale fire safety experiments on an International Space Station...

  3. Fire Stations - 2009

    Data.gov (United States)

    Kansas Data Access and Support Center — Fire Stations in Kansas Any location where fire fighters are stationed or based out of, or where equipment that such personnel use in carrying out their jobs is...

  4. The OECD FIRE database

    International Nuclear Information System (INIS)

    Angner, A.; Berg, H.P.; Roewekamp, M.; Werner, W.; Gauvain, J.

    2007-01-01

    Realistic modelling of fire scenarios is still difficult due to the scarcity of reliable data needed for deterministic and probabilistic fire safety analysis. Therefore, it has been recognized as highly important to establish a fire event database on an international level. In consequence, several member countries of the Nuclear Energy Agency of the OECD have decided in 2000 to establish the International Fire Data Exchange Project (OECD FIRE) to encourage multilateral co-operation in the collection and analysis of data related to fire events at nuclear power plants. This paper presents the OECD FIRE project objectives, work scope and current status of the OECD FIRE database after 3 years of operation as well as first preliminary statistical insights gained from the collected data. (orig.)

  5. Review of methods for modelling forest fire risk and hazard | Yakubu ...

    African Journals Online (AJOL)

    At global scale, fire is the most generalized means of transforming tropical forest in agricultural areas, and it has severe impacts on global atmospheric chemistry. Fire is a natural factor in many climates with high levels of vegetation stress. However, changes in traditional land use such as hunting, charcoal production, ...

  6. FIRE CHARACTERISTICS FOR ADVANCED MODELLING OF FIRES

    Directory of Open Access Journals (Sweden)

    Otto Dvořák

    2016-07-01

    Full Text Available This paper summarizes the material and fire properties of solid flammable/combustible materials /substances /products, which are used as inputs for the computer numerical fire models. At the same time it gives the test standards for their determination.

  7. Exposure to organophosphate flame retardants of hotel room attendants in Wuhan City, China.

    Science.gov (United States)

    Tao, Yun; Shang, Yinzhu; Li, Jing; Feng, Jingwen; He, Zhenyu; Covaci, Adrian; Wang, Peng; Luo, Jing; Mao, Xiang; Shi, Bin; Hu, Liqin; Luo, Dan; Mei, Surong

    2018-05-01

    Indoor environments provide sources of exposure to organophosphate flame retardants (PFRs), which are artificially synthesized fire-protecting agents used as additives in interior products. As public spaces, hotels are required to meet stricter fire-precaution criteria. As such, room attendants may be exposed to higher levels of PFRs. Our goal was to characterize the exposure of hotel room attendants to PFRs by measuring metabolites in their urine and the corresponding parent PFRs in dust and hand-wipes collected from 27 hotels located in Wuhan City, China. The exposure of the attendants was found to be omnipresent: urinary metabolites of PFRs, such as DPHP (diphenyl phosphate), BDCIPP (bis(1,3-dichloro-2-propyl) phosphate), and DoCP (di-o-cresyl phosphate) & DpCP (di-p-cresyl phosphate) were detected with high frequency (87%, 79% and 87%, respectively). We observed that metabolites in post-shift urine were consistently present at higher levels than those in the first morning voids (p  7 stories) had significantly higher BDCIPP and DPHP concentrations than those from low-rise buildings. A possible reason is that high-rise buildings may use high-grade fireproof building materials to meet stricter fire restrictions. Overall, these results indicate that PFRs exposure in hotels is a contributor to the personal exposure of hotel room attendants. Copyright © 2018 Elsevier Ltd. All rights reserved.

  8. Loft fire protection

    International Nuclear Information System (INIS)

    White, E.R.; Jensen, J.D.

    1980-01-01

    Quantified criteria that was developed and applied to provide in-depth fire protection for the Loss of Fluid Test (LOFT) Facility are presented. The presentation describes the evolution process that elevated the facility's fire protection from minimal to that required for a highly protected risk or improved risk. Explored are some infrequently used fire protection measures that are poorly understood outside the fire protection profession

  9. Calibration of the CAFE-3D fire code with controlled indoor fire data

    International Nuclear Information System (INIS)

    Lopez, C.; Koski, J.A.; Khalil, I.; Suo-Anttila, A.

    2004-01-01

    The Container Analysis Fire Environment (CAFE) code contains a computational fluid dynamics (CFD) based fire model that has been successfully coupled to standard finite element computer codes. This coupling of CFD and finite element codes allows for a more realistic modeling of the thermal performance of objects engulfed in fire, which aids in the design and risk analysis of radioactive material packages. The CAFE fire model is based on a three-dimensional finite volume formulation of basic fire chemistry and fluid dynamics. This fire model includes a variable-density primitive-variable formulation of mass, momentum, energy and species equations. Multiple chemical species and soot formation are included in the combustion model. Thermal radiation is modeled as diffusive radiation transport inside the flame zone and as view-factor radiation outside the flame zone. Turbulence is modeled with an eddy diffusivity model. The soot model is coupled to the diffusive radiation formulation using the Rosseland approximation and the optical properties of soot. In order to verify and improve the accuracy of computers codes, they should be benchmarked against test data. This paper describes a set of experiments that were performed at the Fire Laboratory for Accreditation of Modeling by Experiment (FLAME) fire facility of Sandia National Laboratories in Albuquerque, New Mexico, USA. The paper also describes how the data collected from the experiments was used to calibrate and benchmark the CAFE-3D fire code. Detailed description of the tests performed and comparisons between the calculated results and the collected data from the experiments are provided

  10. Electron tunneling in chemistry

    International Nuclear Information System (INIS)

    Zamaraev, K.I.; Khajrutdinov, R.F.; Zhdanov, V.P.; Molin, Yu.N.

    1985-01-01

    Results of experimental and theoretical investigations are outlined systematically on electron tunnelling in chemical reactions. Mechanism of electron transport to great distances is shown to be characteristic to chemical compounds of a wide range. The function of tunnel reactions is discussed for various fields of chemistry, including radiation chemistry, electrochemistry, chemistry of solids, chemistry of surface and catalysis

  11. Fire as Technology

    Science.gov (United States)

    Rudolph, Robert N.

    2011-01-01

    In this article, the author describes a project that deals with fire production as an aspect of technology. The project challenges students to be survivors in a five-day classroom activity. Students research various materials and methods to produce fire without the use of matches or other modern combustion devices, then must create "fire" to keep…

  12. Fourmile Canyon Fire Findings

    Science.gov (United States)

    Russell Graham; Mark Finney; Chuck McHugh; Jack Cohen; Dave Calkin; Rick Stratton; Larry Bradshaw; Ned Nikolov

    2012-01-01

    The Fourmile Canyon Fire burned in the fall of 2010 in the Rocky Mountain Front Range adjacent to Boulder, Colorado. The fire occurred in steep, rugged terrain, primarily on privately owned mixed ponderosa pine and Douglas-fir forests. The fire started on September 6 when the humidity of the air was very dry (¡Ö

  13. Autonomous Forest Fire Detection

    NARCIS (Netherlands)

    Breejen, E. den; Breuers, M.; Cremer, F.; Kemp, R.A.W.; Roos, M.; Schutte, K.; Vries, J.S. de

    1998-01-01

    Forest fire detection is a very important issue in the pre-suppression process. Timely detection allows the suppression units to reach the fire in its initial stages and this will reduce the suppression costs considerably. The autonomous forest fire detection principle is based on temporal contrast

  14. Fire Department Emergency Response

    International Nuclear Information System (INIS)

    Blanchard, A.; Bell, K.; Kelly, J.; Hudson, J.

    1997-09-01

    In 1995 the SRS Fire Department published the initial Operations Basis Document (OBD). This document was one of the first of its kind in the DOE complex and was widely distributed and reviewed. This plan described a multi-mission Fire Department which provided fire, emergency medical, hazardous material spill, and technical rescue services

  15. Equipping tomorrow's fire manager

    Science.gov (United States)

    Christopher A. Dicus

    2008-01-01

    Fire managers are challenged with an ever-increasing array of both responsibilities and critics. As in the past, fire managers must master the elements of fire behavior and ecology using the latest technologies. In addition, today’s managers must be equipped with the skills necessary to understand and liaise with a burgeoning group of vocal stakeholders while also...

  16. Fire and forest meteorology

    Science.gov (United States)

    SA Ferguson; T.J. Brown; M. Flannigan

    2005-01-01

    The American Meteorological Society symposia series on Fire and Forest Meteorology provides biennial forums for atmospheric and fire scientists to introduce and discuss the latest and most relevant research on weather, climate and fire. This special issue highlights significant work that was presented at the Fifth Symposium in Orlando, Florida during 16-20 November...

  17. Cost of two fire

    International Nuclear Information System (INIS)

    Vasil'ev, Yu.

    2001-01-01

    The problem of the protection of nuclear sites in connection with the fires in summer of 2000 near two greatest nuclear sites: the Pacific Northwest National Laboratory located on the site of Hanford Nuclear Center, and Los Alamos National Laboratory is considered. Both fires occur beyond the Laboratories. Undertaken urgent procedures for fire fighting and recovery of the objects are characterized [ru

  18. An Experimental Investigation on Fire Behavior of Expanded Polystyrene

    Directory of Open Access Journals (Sweden)

    S. Bakhtiary

    2007-08-01

    Full Text Available Fire behavior of different types of EPS was evaluated with the use of ISO 5660 cone calorimeter test method. Considering the complexity of behavior of EPS against high temperatures, several specimens were tested, so a betterjudgment on fire behavior of this material could be acquired. The effects of foam density, thickness of specimens and the level of heat flux on fire behavior of foam were examined. The relation between total heat release (THR and heat release rate (HRR with the density of the specimens were examined. The increase of thickness showed a two-fold influence on the fire behavior of the specimens. In one side, the mass of fuel increases with thickness, hence the THR and HRR needs to be increased. Contrary to that however, as EPS quickly melts and recedes away the heat source athigh temperatures, the incident heat flux on specimen conciderably reduces with increase of thickness and as a result the time to ignition will be lengthened with increase of thickness. These observations are discussed in the paper. On the basis of our results the comparison between the fire behavior of fire-retarded and standard types of foam is also discussed in the paper.

  19. Fires of sodium installations

    International Nuclear Information System (INIS)

    Hajek, L.; Tlalka, R.

    1984-01-01

    A survey is presented of the literature dealing with fires of sodium installations between 1974 and 1981. Also described are three experimental fires of ca 50 kg of sodium in an open area, monitored by UJV Rez. The experimental conditions of the experiments are described and a phenomenological description is presented of the course of the fires. The experiments showed a relationship between wind velocity in the area surrounding the fire and surface temperature of the sodium flame. Systems analysis methods were applied to sodium area, spray and tube fires. (author)

  20. Fire Protection Program Manual

    Energy Technology Data Exchange (ETDEWEB)

    Sharry, J A

    2012-05-18

    This manual documents the Lawrence Livermore National Laboratory (LLNL) Fire Protection Program. Department of Energy (DOE) Orders 420.1B, Facility Safety, requires LLNL to have a comprehensive and effective fire protection program that protects LLNL personnel and property, the public and the environment. The manual provides LLNL and its facilities with general information and guidance for meeting DOE 420.1B requirements. The recommended readers for this manual are: fire protection officers, fire protection engineers, fire fighters, facility managers, directorage assurance managers, facility coordinators, and ES and H team members.

  1. 38 CFR 4.127 - Mental retardation and personality disorders.

    Science.gov (United States)

    2010-07-01

    ... AFFAIRS SCHEDULE FOR RATING DISABILITIES Disability Ratings Mental Disorders § 4.127 Mental retardation and personality disorders. Mental retardation and personality disorders are not diseases or injuries... from them may not be service-connected. However, disability resulting from a mental disorder that is...

  2. Fatigue crack growth retardation in spot heated mild steel sheet

    Indian Academy of Sciences (India)

    A fatigue crack can be effectively retarded by heating a spot near the crack tip under nil remote stress condition. The subcritical spot heating at a proper position modifies the crack growth behaviour in a way, more or less, similar to specimen subjected to overload spike. It is observed that the extent of crack growth retardation ...

  3. Piagetian Object Permanence in Severely Mentally Retarded Adults.

    Science.gov (United States)

    Brekke, Beverly; And Others

    The measurability of sensorimotor development in 60 severely retarded, institutionalized adults was studied, using the Piagetian concept of object permanence in a delayed recall paradigm that involved special apparatus. Results suggested, among other things, that severely retarded, institutionalized adults learn most efficiently when trained with…

  4. Sex between persons with 'mental retardation': an ethical evaluation

    NARCIS (Netherlands)

    Spiecker, B.; Steutel, J.W.

    2002-01-01

    Is sex between people with "mental retardation" morally permissible and, if at all, under what conditions? This paper tries to answer this question, but only with regard to sex between biologically mature individuals with mild or moderate mental retardation. First, the concepts of "sexual activity"

  5. Growth retardation in children injected with 224Ra

    International Nuclear Information System (INIS)

    Spiess, H.; Mays, C.W.; Spiess-Paulus, E.

    1986-01-01

    We have obtained the adult heights of 133 patients formerly injected with 224 Ra as juveniles. 224 Ra induced growth retardation was greatest in children injected at young ages and increased with dose. The growth retardation was well represented as a 2% decrease in potential growth post irradiation per 100 rads of calculated average skeletal dose. (orig.)

  6. Decision Making in Leisure. Empowerment for People with Mental Retardation.

    Science.gov (United States)

    Bullock, Charles C.; Mahon, Michael J.

    1992-01-01

    People with mental retardation have been overlooked in recreation/leisure and decision making, which are integral to full community participation. They must be provided with leisure education and decision-making skills. The article describes the Decision Making in Leisure model, explaining its use with individuals with mental retardation. (SM)

  7. Brominated flame retardants: occurrence, dietary intake and risk assessment

    NARCIS (Netherlands)

    Winter-Sorkina R de; Bakker MI; Wolterink G; Zeijlmaker MJ; SIR

    2006-01-01

    Brominated flame retardants have entered the human food chain. For the time being the occurrence of these chemicals in Dutch food does not pose a human health risk. However, this might easily change at increasing contents of flame retardants in Dutch food. The monitoring of brominated flame

  8. Psychiatric Illness in Mentally Retarded Adolescents: Clinical Features.

    Science.gov (United States)

    Masi, Gabriele

    1998-01-01

    Describes the clinical features of the most important psychiatric disorders in mentally retarded adolescents: mood disorders, psychotic disorders, severe behavioral disorders, personality disorders, anxiety disorders, and attention-deficit The impact of mental retardation on personality development is confirmed by the high psychopathological…

  9. Flame retardants: Dust - and not food - might be the risk

    NARCIS (Netherlands)

    de Boer, J.; Ballesteros-Gomez, A.M.; Leslie, H.A.; Brandsma, S.H.; Leonards, P.E.G.

    2016-01-01

    Flame retardants (FRs) are used to delay ignition of materials such as furniture and electric and electronic instruments. Many FRs are persistent and end up in the environment. Environmental studies on flame retardants (FRs) took off in the late 1990s. Polybrominated diphenylethers (PBDEs) appeared

  10. Perceptual-Motor Attributes of Mentally Retarded Youth.

    Science.gov (United States)

    Cratty, Bryant J.

    To evaluate six perceptual-motor attributes of trainable and educable mentally retarded children, a battery of tests was constructed which included body perception, gross agility, balance, locomotor ability, throwing, and tracking; 83 retarded subjects provided reliability data, and their scores, with those of 120 additional subjects, provided…

  11. Labeling, Rehearsal, and Short-Term Memory in Retarded Children

    Science.gov (United States)

    Hagen, John W.; And Others

    1974-01-01

    A short-term memory task was used to explore the effects of verbal labeling and rehearsal on serial-position recall in mildly retarded 9-to 11-year-old children. Results support the view that verbal skills affect recall in mildly retarded children similarly to normal children. (Author/SDH)

  12. Theories on Criminality and Mental Retardation Project CAMIO, Volume 2.

    Science.gov (United States)

    Haskins, Jimmy R.; Friel, Charles M.

    This historical review of theories on criminality and mental retardation is part of Project CAMIO (Correctional Administration and the Mentally Incompetent Offender), a Texas study to determine the incidence of criminal incarceration of the mentally retarded (MR) and to identify laws, procedures, and practices which affect the prosecution and…

  13. Muscle Fatigue during Intermittent Exercise in Individuals with Mental Retardation

    Science.gov (United States)

    Zafeiridis, Andreas; Giagazoglou, Paraskevi; Dipla, Konstantina; Salonikidis, Konstantinos; Karra, Chrisanthi; Kellis, Eleftherios

    2010-01-01

    This study examined fatigue profile during intermittent exercise in 10 men with mild to moderate mental retardation (MR) and 10 men without mental retardation (C). They performed 4 x 30 s maximal knee extensions and flexions with 1-min rest on an isokinetic dynamometer. Peak torque of flexors (PTFL) and extensors (PTEX), total work (TW), and…

  14. Life cycle assessment of flame retardants in an electronics application

    NARCIS (Netherlands)

    Jonkers, Niels; Krop, Hildo; van Ewijk, Harry; Leonards, Pim E.G.

    2016-01-01

    Purpose: Flame retardants are added to plastics and textiles to save lives. However, certain brominated flame retardants (BFRs) form an environmental hazard and should be replaced by less harmful alternatives. In the recently completed European research project ENFIRO, we examined which alternatives

  15. Trace element analysis of hair of mentally retarded children

    International Nuclear Information System (INIS)

    Bhandari, H.P.S.; Lal, G.; Sidhu, N.P.S.; Mittal, V.K.; Sahota, H.S.

    1987-01-01

    Unlike previously reported, Zn and Se levels were found to be the same in the hair of mentally retarded children and controls. Non-essential toxic Ag concentration was low whereas that of Hg, Au and Sc rather high in mentally retarded children. (author) 4 refs

  16. Iconic Memory Deficit of Mildly Mentally Retarded Individuals.

    Science.gov (United States)

    Hornstein, Henry A.; Mosley, James L.

    1987-01-01

    Ten mildly retarded young adult males and nonretarded subjects matched for chronological age or mental age were required to recognize both verbal and nonverbal stimuli presented tachistoscopically. Results of a backward visual masking paradigm varying stimulus onset asynchrony (SOA) indicated the retarded subjects performed poorer at the longest…

  17. Cognitive Representation of Motion in Individuals with Mental Retardation.

    Science.gov (United States)

    Conners, Frances A.; Wyatt, Beverly S.; Dulaney, Cynthia L.

    1998-01-01

    Fifteen adolescents with and 15 without mental retardation were compared on their tendency to show the representational momentum effect when viewing a stimulus array that implied motion. Participants with mental retardation showed the representational momentum effects as did the others, although the magnitude of the memory shift was smaller.…

  18. Adoptive and Birth Family Adjustment to Rearing Retarded Children.

    Science.gov (United States)

    Glidden, Laraine Masters; Bush, Beverly A.

    The study identified 81 families who adopted children with mental retardation or at risk for mental retardation, and compared them with 61 matched families with similar birth children. For birth families, the initial diagnosis was a time of crisis, with high depression scores, while scores at follow-up (an average of 5.3 years later) indicated no…

  19. A mentally retarded patient with schizophrenia.

    Science.gov (United States)

    Rabia, K; Khoo, Em

    2008-01-01

    Schizophrenia is one of the most incapacitating forms of mental disorder that runs a chronic and relapsing course. It typically starts in adolescence or early adulthood and can be life-long. It is more common in people with learning disabilities than in the general population. Its prodromal features include depression, anxiety, suspiciousness, social isolation and bizarre behaviour. It may result in significant functional, social and economic impairments. The care of patients with schizophrenia places a considerable burden on all carers including patient's family, health and social services. Treatment includes pharmacotherapy and psychosocial interventions. In this case report we describe a thirteen-year-old patient with schizophrenia who has a background history of mental retardation.

  20. A MENTALLY RETARDED PATIENT WITH SCHIZOPHRENIA

    Directory of Open Access Journals (Sweden)

    KHOO EM

    2008-01-01

    Full Text Available Schizophrenia is one of the most incapacitating forms of mental disorder that runs a chronic and relapsing course. It typically starts in adolescence or early adulthood and can be life-long. It is more common in people with learning disabilities than in the general population. Its prodromal features include depression, anxiety, suspiciousness, social isolation and bizarre behaviour. It may result in significant functional, social and economic impairments. The care of patients with schizophrenia places a considerable burden on all carers including patient’s family, health and social services. Treatment includes pharmacotherapy and psychosocial interventions. In this case report we describe a thirteen-year-old patient with schizophrenia who has a background history of mental retardation.

  1. Relativistic quarkonium model with retardation effect, 1

    International Nuclear Information System (INIS)

    Ito, Hitoshi

    1990-01-01

    A new relativistic two-body equation is proposed which has the charge-conjugation symmetry. The renormalization of the wave function at the origin (WFO) is done by incorporating the corresponding vertex equation. By using this model, the heavy-quarkonium phenomenology is developed putting emphasis on the short-distance interaction. The typical scale of the distance restricting the applicability of the ladder model for the mass spectra is found to be 0.13 fm: By assuming the equivalent high-momentum cutoff for the gluonic correction, good results are obtained for the charmonium masses. The improved fine-splittings of the bb-bar states are obtained by inclusion of the retardation. Leptonic decay rates are predicted by assuming the renormalized WFO reduced by another high-momentum cutoff. (author)

  2. Adsorption and Retardation of PFASs in Soil

    Science.gov (United States)

    Chen, W.; Yan, N.; Fu, X.; Carroll, K. C.; Holguin, F. O. O.; Brusseau, M. L.

    2017-12-01

    Per- and poly-fluorinated alkyl substances (PFASs) are emerging contaminants of concern that are present in the subsurface at numerous military and industrial facilities. Knowledge of the retention behavior of these compounds in the subsurface environment is critical for effective risk characterization and remediation. The objective of this research is to investigate the role of adsorption at the air-water interface on PFAS retention in vadose-zone systems. Surface tensions were measured for select PFAS to determine interfacial adsorption coefficients. Column experiments were conducted to characterize retardation and transport under saturated and unsaturated flow conditions. The impact of soil properties and groundwater constituents on surface tension, solid-phase adsorption, and interfacial adsorption was investigated.

  3. Referential first mention in narratives by mildly mentally retarded adults.

    Science.gov (United States)

    Kernan, K T; Sabsay, S

    1987-01-01

    Referential first mentions in narrative reports of a short film by 40 mildly mentally retarded adults and 20 nonretarded adults were compared. The mentally retarded sample included equal numbers of male and female, and black and white speakers. The mentally retarded speakers made significantly fewer first mentions and significantly more errors in the form of the first mentions than did nonretarded speakers. A pattern of better performance by black males than by other mentally retarded speakers was found. It is suggested that task difficulty and incomplete mastery of the use of definite and indefinite forms for encoding old and new information, rather than some global type of egocentrism, accounted for the poorer performance by mentally retarded speakers.

  4. Green chemistry: A tool in Pharmaceutical Chemistry

    OpenAIRE

    Smita Talaviya; Falguni Majumdar

    2012-01-01

    Green chemistry expresses an area of research developing from scientific discoveries about pollution awareness and it utilizes a set of principles that reduces or eliminates the use or generation of hazardous substances in all steps of particular synthesis or process. Chemists and medicinal scientists can greatly reduce the risk to human health and the environment by following all the valuable principles of green chemistry. The most simple and direct way to apply green chemistry in pharmaceut...

  5. Effect of electron beam irradiation and microencapsulation on the flame retardancy of ethylene-vinyl acetate copolymer materials during hot water ageing test

    International Nuclear Information System (INIS)

    Sheng, Haibo; Zhang, Yan; Wang, Bibo; Yu, Bin; Shi, Yongqian; Song, Lei; Kundu, Chanchal Kumar; Tao, Youji; Jie, Ganxin; Feng, Hao; Hu, Yuan

    2017-01-01

    Microencapsulated ammonium polyphosphate (MCAPP) in combination with polyester polyurethane (TPU) was used to flame retardant ethylene-vinyl acetate copolymer (EVA). The EVA composites with different irradiation doses were immersed in hot water (80 °C) to accelerate ageing process. The microencapsulation and irradiation dose ensured positive impacts on the properties of the EVA composites in terms of better dimensional stability and flame retardant performance. The microencapsulation of APP could lower its solubility in water and the higher irradiation dose led to the more MCAPP immobilized in three dimensional crosslinked structure of the EVA matrix which could jointly enhance the flame retardant and electrical insulation properties of the EVA composites. So, the EVA composites with 180 kGy irradiation dose exhibited better dimensional stability than the EVA composites with 120 kGy due to the higher crosslinking degree. Moreover, the higher irradiation dose lead to the more MCAPP immobilizated in crosslinked three-dimensional structure of EVA, enhancing the flame retardancy and electrical insulation properties of the EVA composites. After ageing test in hot water at 80 °C for 2 weeks, the EVA/TPU/MCAPP composite with 180 kGy could still maintain the UL-94 V-0 rating and the limiting oxygen index (LOI) value was as high as 30%. This investigation indicated the flame retardant EVA cable containing MCAPP could achieve stable properties and lower electrical fire hazard risk during long-term hot water ageing test. - Highlights: • Microencapsulated ammonium polyphosphate is prepared by successive sol-gel process. • The higher irradiation dose induces the better dimensional stability for EVA system. • The higher irradiation, the more MCAPP immobilized in EVA crosslinked structure. • The higher irradiation dose enhances the flame retardancy of EVA composites. • The microencapsulated composites demonstrate stable flame retardancy in ageing test.

  6. Fire risk in California

    Science.gov (United States)

    Peterson, Seth Howard

    Fire is an integral part of ecosystems in the western United States. Decades of fire suppression have led to (unnaturally) large accumulations of fuel in some forest communities, such as the lower elevation forests of the Sierra Nevada. Urban sprawl into fire prone chaparral vegetation in southern California has put human lives at risk and the decreased fire return intervals have put the vegetation community at risk of type conversion. This research examines the factors affecting fire risk in two of the dominant landscapes in the state of California, chaparral and inland coniferous forests. Live fuel moisture (LFM) is important for fire ignition, spread rate, and intensity in chaparral. LFM maps were generated for Los Angeles County by developing and then inverting robust cross-validated regression equations from time series field data and vegetation indices (VIs) and phenological metrics from MODIS data. Fire fuels, including understory fuels which are not visible to remote sensing instruments, were mapped in Yosemite National Park using the random forests decision tree algorithm and climatic, topographic, remotely sensed, and fire history variables. Combining the disparate data sources served to improve classification accuracies. The models were inverted to produce maps of fuel models and fuel amounts, and these showed that fire fuel amounts are highest in the low elevation forests that have been most affected by fire suppression impacting the natural fire regime. Wildland fires in chaparral commonly burn in late summer or fall when LFM is near its annual low, however, the Jesusita Fire burned in early May of 2009, when LFM was still relatively high. The HFire fire spread model was used to simulate the growth of the Jesusita Fire using LFM maps derived from imagery acquired at the time of the fire and imagery acquired in late August to determine how much different the fire would have been if it had occurred later in the year. Simulated fires were 1.5 times larger

  7. The chemistry of stratospheric ozone

    International Nuclear Information System (INIS)

    Kurylo, M.J.

    1990-01-01

    Compelling observational evidence shows that the chemical composition of the atmosphere is changing on a global scale at a rapid rate. The atmospheric concentrations of carbon dioxide (CO 2 ), methane (CH 4 ), nitrous oxide (N 2 O), and chloroflourocarbons (CFCs) 11 (CFCl 3 ) and 12 (CF 2 Cl 2 ) are currently increasing at rate ranging from 0.2 to 5% per year. The concentrations of other cases, including CFC 113 (C 2 F 3 Cl 3 ) and halons 121 (CF 2 ClBr) and 1301 (CF 3 Br), important in the ozone depletion and global warming issues, are also increasing (at even faster rates). These changes in atmospheric composition reflect, on one part, the metabolism of the biosphere and, on another, the broad range of influencing human activities, including industrial, agricultural, and combustion practices. The only known sources of the CFCs and halons are industrial production prior to their use as aerosol propellants, refrigerants, foam blowing agents, solvents, and fire retardants. One of our greatest difficulties in accurately predicting future changes in ozone or global warming is our inability to predict the future atmospheric concentrations of these gases. This paper discusses the role of the biosphere in regulating the emissions of gases such as CH 4 , CO 2 , N 2 O, and methyl chloride (CH 3 Cl) to the atmosphere as well as the most probable future industrial release rates of the CFCs, halons, N 2 O, carbon monoxide (CO), and CO 2 , which depend upon a variety of economic, social, and political factors

  8. From hot atom chemistry to epithermal chemistry

    International Nuclear Information System (INIS)

    Roessler, K.

    2004-01-01

    The rise and fall of hot atom chemistry (HAC) over the years from 1934 to 2004 is reviewed. Several applications are discussed, in particular to astrophysics and the interaction of energetic ions and atoms in space. Epithermal chemistry (ETC) is proposed to substitute the old name, since it better fits the energy range as well as the non-thermal and non-equilibrium character of the reactions. ETC also avoids the strong connexion of HAC to nuclear chemistry and stands for the opening of the field to physical chemistry and astrophysics. (orig.)

  9. Development of flame retardant and anti-pollution (AP) electric cable

    International Nuclear Information System (INIS)

    Fujimura, Shunichi; Ishitani, Hayao; Sakamoto, Kazuhide; Ohtani, Kenichi; Udoh, Sinichi; Hisatsune, Toyokazu; Igarashi, Yasuhiro; Ohya, Shingo; Handa, Katsue

    1985-01-01

    Varies means are in use to prevent the spread of cable fire. But little attention has been paid to the generation of smoke, corrosive gas, and toxic gas from burning cables. In Europe control on gas-producing cables is widespread, and Japan is beginning to be influenced by it. The authors report their development of what is called ''anti-pollution flame-retardant cable'' which produces no metal-corroding and highly toxic halogenides and only very little smoke. The AP cable can be designed in varied constructions according to the applications for which it is used. It is therefore usable for power transmission, communications, ships, vehicles, nuclear power facilities, etc. (author)

  10. Studies on incorporation of exfoliated bentonitic clays in polyurethane foams for increasing flame retardancy

    International Nuclear Information System (INIS)

    Quagliano, J; García, Irma Gavilán

    2012-01-01

    In this contribution we report the results of studying the incorporation of exfoliated bentonitic clays into polyurethane foams. A suspension in water of a sodium bentonite from Argentine Patagonia was interchanged with cetyl trimethyl ammonium bromide (CTAB) for 4 h at 80°C, rendering an exfoliated clay, which is nanometric in only one dimension. This nanoclay, when dispersed in the polyurethane, resulted in the same fire retardancy rating (UL-94) than when polyurethane was treated with a commercial nanoclay. Scanning electron microscopy (SEM) at low augmentations of polyurethane samples treated with the synthethized nanoclay (2,5% w/w) showed no differences respect to untreated polyurethane, except for the irregularity of void edges.

  11. A process for imparting durable flame retardancy to fabric, fibres and other materials

    International Nuclear Information System (INIS)

    Nablo, S.V.

    1981-01-01

    The invention provides a process for grafting a fire-retarding additive including one or more phosphorus and/or halogen-rich compounds to fabrics, fibres and other flammable materials, the process comprising: applying to the material a solution of the additive and a copolymerization-grafting compound for effecting copolymerization with the additive; adjusting the solids content of the applied solution to correspond to a predetermined desired add-on level; at least partly drying the material; exposing the material so treated to an electron irradiating beam; and adjusting the electron irradiation within energy ranges of substantially 50 to 250 keV and dose levels of from substantially 2 to 5 megarads. (author)

  12. Measurement of the flame retardants polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCDD) in house dust

    Energy Technology Data Exchange (ETDEWEB)

    Stapleton, H.; Dodder, N.; Schantz, M.; Wise, S. [National Institute of Standards and Technology, Gaithersburg, MD (United States)

    2004-09-15

    Current monitoring of polybrominated diphenyl ethers (PBDEs) has shown that concentrations are increasing in the environment very rapidly with doubling times as short as three to five years. North America consumes a large percentage of the global market demand for PBDEs, and as a result, concentrations of PBDEs in human milk and serum are an order of magnitude higher in women from North America relative to Europe. Within sampled populations, PBDE levels in human serum have been shown to range over an order of magnitude, and high levels cannot always be attributed to occupational exposure, age or diet. One source that may be responsible for these observations is exposure in the home. These compounds are liberally applied to many common household items such as furniture, mattresses, computers and TVs to retard or hinder the outbreak of fire. Over time, these flame retardants may leach out into the home environment, where they may be inhaled or ingested, resulting in elevated levels in human serum. Very few studies have examined PBDE levels within the home and only one study has measured the concentrations of two PBDE congeners in house dust. The present study was undertaken to measure a suite PBDE congeners in house dust from a variety of homes and to assess the contribution of the three commercial PBDE mixtures (penta-, octa- and decaBDE) to the house dust composition. In addition, we also measured the concentrations of hexabromocyclododecane (HBCDD), another flame retardant. Correlations with properties of the houses such as year of construction, square footage, carpeting coverage and number of computers in the house were also examined for any positive influences.

  13. Fire Danger and Fire Weather Records

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The National Weather Service (formerly Weather Bureau) and Forest Service developed a program to track meteorological conditions conducive to forest fires, resulting...

  14. The latest general chemistry

    International Nuclear Information System (INIS)

    Ryu, Geun Bae; Choi, Se Yeong; Kim, Chin Yeong; Yoon, Gil Jung; Lee, Eun Seok; Seo, Moon Gyu

    1995-02-01

    This book deals with the latest general chemistry, which is comprised of twenty-three chapters, the contents of this book are introduction, theory of atoms and molecule, chemical formula and a chemical reaction formula, structure of atoms, nature of atoms and the periodic table, structure of molecule and spectrum, gas, solution, solid, chemical combination, chemical reaction speed, chemical equilibrium, thermal chemistry, oxidation-reduction, electrochemistry, acid-base, complex, aquatic chemistry, air chemistry, nuclear chemistry, metal and nonmetal, organic chemistry and biochemistry. It has exercise in the end of each chapter.

  15. Constitutional dynamic chemistry: bridge from supramolecular chemistry to adaptive chemistry.

    Science.gov (United States)

    Lehn, Jean-Marie

    2012-01-01

    Supramolecular chemistry aims at implementing highly complex chemical systems from molecular components held together by non-covalent intermolecular forces and effecting molecular recognition, catalysis and transport processes. A further step consists in the investigation of chemical systems undergoing self-organization, i.e. systems capable of spontaneously generating well-defined functional supramolecular architectures by self-assembly from their components, thus behaving as programmed chemical systems. Supramolecular chemistry is intrinsically a dynamic chemistry in view of the lability of the interactions connecting the molecular components of a supramolecular entity and the resulting ability of supramolecular species to exchange their constituents. The same holds for molecular chemistry when the molecular entity contains covalent bonds that may form and break reversibility, so as to allow a continuous change in constitution by reorganization and exchange of building blocks. These features define a Constitutional Dynamic Chemistry (CDC) on both the molecular and supramolecular levels.CDC introduces a paradigm shift with respect to constitutionally static chemistry. The latter relies on design for the generation of a target entity, whereas CDC takes advantage of dynamic diversity to allow variation and selection. The implementation of selection in chemistry introduces a fundamental change in outlook. Whereas self-organization by design strives to achieve full control over the output molecular or supramolecular entity by explicit programming, self-organization with selection operates on dynamic constitutional diversity in response to either internal or external factors to achieve adaptation.The merging of the features: -information and programmability, -dynamics and reversibility, -constitution and structural diversity, points to the emergence of adaptive and evolutive chemistry, towards a chemistry of complex matter.

  16. Biogenic volatile organic compound emissions from vegetation fires.

    Science.gov (United States)

    Ciccioli, Paolo; Centritto, Mauro; Loreto, Francesco

    2014-08-01

    The aim of this paper was to provide an overview of the current state of the art on research into the emission of biogenic volatile organic compounds (BVOCs) from vegetation fires. Significant amounts of VOCs are emitted from vegetation fires, including several reactive compounds, the majority belonging to the isoprenoid family, which rapidly disappear in the plume to yield pollutants such as secondary organic aerosol and ozone. This makes determination of fire-induced BVOC emission difficult, particularly in areas where the ratio between VOCs and anthropogenic NOx is favourable to the production of ozone, such as Mediterranean areas and highly anthropic temperate (and fire-prone) regions of the Earth. Fire emissions affecting relatively pristine areas, such as the Amazon and the African savannah, are representative of emissions of undisturbed plant communities. We also examined expected BVOC emissions at different stages of fire development and combustion, from drying to flaming, and from heatwaves coming into contact with unburned vegetation at the edge of fires. We conclude that forest fires may dramatically change emission factors and the profile of emitted BVOCs, thereby influencing the chemistry and physics of the atmosphere, the physiology of plants and the evolution of plant communities within the ecosystem. © 2014 The Authors. Plant, Cell & Environment published by John Wiley & Sons Ltd.

  17. All fired up

    CERN Multimedia

    CERN Bulletin

    2013-01-01

    Members of the Directorate and their support staff took part in a fire-fighting course organised by the CERN Fire Brigade just before the end-of-year break.  The Bulletin takes a look at the fire-fighting training on offer at CERN.   At CERN the risk of fire can never be under-estimated. In order to train personnel in the use of fire extinguishers, CERN's fire training centre in Prévessin acquired a fire-simulation platform in 2012. On the morning of 17 December 2012, ten members of the CERN directorate and their support staff tried out the platform, following in the footsteps of 400 other members of the CERN community who had already attended the course. The participants were welcomed to the training centre by Gilles Colin, a fire-fighter and instructor, who gave them a 30-minute introduction to general safety and the different types of fire and fire extinguishers, followed by an hour of practical instruction in the simulation facility. There they were able to pract...

  18. Managing wildland fires: integrating weather models into fire projections

    Science.gov (United States)

    Anne M. Rosenthal; Francis Fujioka

    2004-01-01

    Flames from the Old Fire sweep through lands north of San Bernardino during late fall of 2003. Like many Southern California fires, the Old Fire consumed susceptible forests at the urban-wildland interface and spread to nearby city neighborhoods. By incorporating weather models into fire perimeter projections, scientist Francis Fujioka is improving fire modeling as a...

  19. The theory, direction, and magnitude of ecosystem fire probability as constrained by precipitation and temperature.

    Science.gov (United States)

    Guyette, Richard; Stambaugh, Michael C; Dey, Daniel; Muzika, Rose Marie

    2017-01-01

    The effects of climate on wildland fire confronts society across a range of different ecosystems. Water and temperature affect the combustion dynamics, irrespective of whether those are associated with carbon fueled motors or ecosystems, but through different chemical, physical, and biological processes. We use an ecosystem combustion equation developed with the physical chemistry of atmospheric variables to estimate and simulate fire probability and mean fire interval (MFI). The calibration of ecosystem fire probability with basic combustion chemistry and physics offers a quantitative method to address wildland fire in addition to the well-studied forcing factors such as topography, ignition, and vegetation. We develop a graphic analysis tool for estimating climate forced fire probability with temperature and precipitation based on an empirical assessment of combustion theory and fire prediction in ecosystems. Climate-affected fire probability for any period, past or future, is estimated with given temperature and precipitation. A graphic analyses of wildland fire dynamics driven by climate supports a dialectic in hydrologic processes that affect ecosystem combustion: 1) the water needed by plants to produce carbon bonds (fuel) and 2) the inhibition of successful reactant collisions by water molecules (humidity and fuel moisture). These two postulates enable a classification scheme for ecosystems into three or more climate categories using their position relative to change points defined by precipitation in combustion dynamics equations. Three classifications of combustion dynamics in ecosystems fire probability include: 1) precipitation insensitive, 2) precipitation unstable, and 3) precipitation sensitive. All three classifications interact in different ways with variable levels of temperature.

  20. Evaluation of Inheritance Pattern in Mentally Retarded Children

    Directory of Open Access Journals (Sweden)

    F Behnaz

    2011-07-01

    Full Text Available Introduction: Mental retardation is one of the most important problems of general health. The purpose of this study was to evaluate inheritance pattern of mentally retarded patients in Yazd city. Methods: In a descriptive cross- sectional study, all medical records and pedigrees of 320 mentally retarded children whose parents had referred for genetic consultation to the Welfare center of Yazd city were reviewed. Results: Of the total, 62.8% of the parents had consanguineous marriage. Mean inbreeding coefficient of offsprings was 0.0713 in third degree related parents versus 0.0156 in non-related parents. Mental retardation was seen in 43.4% of first– degree relatives of children (6.6% of parents and 36.8% of siblings, respectively. Frequency of mental retardation did not differ significantly in both sexes. Pedigree showed inheritance pattern in 43.4% of patients (autosomal recessive, autosomal dominant and x-linked inheritance pattern were seen in 33.75%, 6.9% and 2.8%, respectively, while 37% of patients had no definite inheritance pattern. Abnormal karyotype were seen in 19.4% of patients, 28 of whom(8.75% of all patients had Down syndrome. The prevalence of autosomal recessive inheritance in patients with consanguineous marriages and non family marriages was 62.8 % and 10%, respectively (P=0. 002. Conclusion: Since multiple cases of mental retardation were seen in families and rate of consanguineous marriage was more in parents of mentally retarded children, genetic counseling in consanguinity marriages and families of mentally retarded children can prevent incidence of mental retardation in these families.

  1. Fire-Induced Response in Foam Encapsulants

    Energy Technology Data Exchange (ETDEWEB)

    Borek, T.T.; Chu, T.Y.; Erickson, K.L.; Gill, W.; Hobbs, M.L.; Humphries, L.L.; Renlund, A.M.; Ulibarri, T.A.

    1999-04-02

    The paper provides a concise overview of a coordinated experimental/theoretical/numerical program at Sandia National Laboratories to develop an experimentally validated model of fire-induced response of foam-filled engineered systems for nuclear and transportation safety applications. Integral experiments are performed to investigate the thermal response of polyurethane foam-filled systems exposed to fire-like heat fluxes. A suite of laboratory experiments is performed to characterize the decomposition chemistry of polyurethane. Mass loss and energy associated with foam decomposition and chemical structures of the virgin and decomposed foam are determined. Decomposition chemistry is modeled as the degradation of macromolecular structures by bond breaking followed by vaporization of small fragments of the macromolecule with high vapor pressures. The chemical decomposition model is validated against the laboratory data. Data from integral experiments is used to assess and validate a FEM foam thermal response model with the chemistry model developed from the decomposition experiments. Good agreement was achieved both in the progression of the decomposition front and the in-depth thermal response.

  2. Biomass co-firing

    DEFF Research Database (Denmark)

    Yin, Chungen

    2013-01-01

    Co-firing biomass with fossil fuels in existing power plants is an attractive option for significantly increasing renewable energy resource utilization and reducing CO2 emissions. This chapter mainly discusses three direct co-firing technologies: pulverized-fuel (PF) boilers, fluidized-bed combus......Co-firing biomass with fossil fuels in existing power plants is an attractive option for significantly increasing renewable energy resource utilization and reducing CO2 emissions. This chapter mainly discusses three direct co-firing technologies: pulverized-fuel (PF) boilers, fluidized......-bed combustion (FBC) systems, and grate-firing systems, which are employed in about 50%, 40% and 10% of all the co-firing plants, respectively. Their basic principles, process technologies, advantages, and limitations are presented, followed by a brief comparison of these technologies when applied to biomass co...

  3. Fire safety analysis: methodology

    International Nuclear Information System (INIS)

    Kazarians, M.

    1998-01-01

    From a review of the fires that have occurred in nuclear power plants and the results of fire risk studies that have been completed over the last 17 years, we can conclude that internal fires in nuclear power plants can be an important contributor to plant risk. Methods and data are available to quantify the fire risk. These methods and data have been subjected to a series of reviews and detailed scrutiny and have been applied to a large number of plants. There is no doubt that we do not know everything about fire and its impact on a nuclear power plants. However, this lack of knowledge or uncertainty can be quantified and can be used in the decision making process. In other words, the methods entail uncertainties and limitations that are not insurmountable and there is little or no basis for the results of a fire risk analysis fail to support a decision process

  4. Advanced Chemistry Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — Description/History: Chemistry laboratoryThe Advanced Chemistry Laboratory (ACL) is a unique facility designed for working with the most super toxic compounds known...

  5. Electrostatics in Chemistry

    Indian Academy of Sciences (India)

    fundamental concepts of electrostatics as applied to atoms and molecules. The electric ... chemistry, the chemistry of the covalent bond, deals with the structures ..... the position of an asteroid named Ceres ... World Scientific. Singapore, 1992.

  6. Little Bear Fire Summary Report

    Science.gov (United States)

    Sarah McCaffrey; Melanie Stidham; Hannah. Brenkert-Smith

    2013-01-01

    In June 2012, immediately after the Little Bear Fire burned outside Ruidoso, New Mexico, a team of researchers interviewed fire managers, local personnel, and residents to understand perceptions of the event itself, communication, evacuation, and pre-fire preparedness. The intensity of fire behavior and resulting loss of 242 homes made this a complex fire with a...

  7. Fire management in central America

    Science.gov (United States)

    Andrea L. Koonce; Armando González-Cabán

    1992-01-01

    Information on fire management operations in Central America is scant. To evaluate the known level of fire occurrence in seven countries in that area, fire management officers were asked to provide information on their fire control organizations and on any available fire statistics. The seven countries surveyed were Guatemala, Belize, Honduras, El Salvador, Nicaragua,...

  8. The human and fire connection

    Science.gov (United States)

    Theresa B. Jain

    2014-01-01

    We refer to fire as a natural disturbance, but unlike other disturbances such as forest insects and diseases, fire has had an intimate relationship with humans. Fire facilitated human evolution over two million years ago when our ancestors began to use fire to cook. Fire empowered our furbearers to adapt to cold climates, allowing humans to disperse and settle into...

  9. Plasma chemistry in wire chambers

    International Nuclear Information System (INIS)

    Wise, J.

    1990-05-01

    The phenomenology of wire chamber aging is discussed and fundamentals of proportional counters are presented. Free-radical polymerization and plasma polymerization are discussed. The chemistry of wire aging is reviewed. Similarities between wire chamber plasma (>1 atm dc-discharge) and low-pressure rf-discharge plasmas, which have been more widely studied, are suggested. Construction and use of a system to allow study of the plasma reactions occurring in wire chambers is reported. A proportional tube irradiated by an 55 Fe source is used as a model wire chamber. Condensable species in the proportional tube effluent are concentrated in a cryotrap and analyzed by gas chromatography/mass spectrometry. Several different wire chamber gases (methane, argon/methane, ethane, argon/ethane, propane, argon/isobutane) are tested and their reaction products qualitatively identified. For all gases tested except those containing methane, use of hygroscopic filters to remove trace water and oxygen contaminants from the gas resulted in an increase in the average molecular weight of the products, consistent with results from low-pressure rf-discharge plasmas. It is suggested that because water and oxygen inhibit polymer growth in the gas phase that they may also reduce polymer deposition in proportional tubes and therefore retard wire aging processes. Mechanistic implications of the plasma reactions of hydrocarbons with oxygen are suggested. Unresolved issues in this work and proposals for further study are discussed

  10. Designing fire safe interiors.

    Science.gov (United States)

    Belles, D W

    1992-01-01

    Any product that causes a fire to grow large is deficient in fire safety performance. A large fire in any building represents a serious hazard. Multiple-death fires almost always are linked to fires that grow quickly to a large size. Interior finishes have large, continuous surfaces over which fire can spread. They are regulated to slow initial fire growth, and must be qualified for use on the basis of fire tests. To obtain meaningful results, specimens must be representative of actual installation. Variables--such as the substrate, the adhesive, and product thickness and density--can affect product performance. The tunnel test may not adequately evaluate some products, such as foam plastics or textile wall coverings, thermoplastic materials, or materials of minimal mass. Where questions exist, products should be evaluated on a full-scale basis. Curtains and draperies are examples of products that ignite easily and spread flames readily. The present method for testing curtains and draperies evaluates one fabric at a time. Although a fabric tested alone may perform well, fabrics that meet test standards individually sometimes perform poorly when tested in combination. Contents and furnishings constitute the major fuels in many fires. Contents may involve paper products and other lightweight materials that are easily ignited and capable of fast fire growth. Similarly, a small source may ignite many items of furniture that are capable of sustained fire growth. Upholstered furniture can reach peak burning rates in less than 5 minutes. Furnishings have been associated with many multiple-death fires.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Wildland Fire Management Plan

    Energy Technology Data Exchange (ETDEWEB)

    Schwager, K. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2017-09-30

    The Wildland Fire Management Plan (FMP) for Brookhaven National Lab (BNL) is written to comply with Department of Energy (DOE) Integrated Safety Management Policy; Federal Wildland Fire Management Policy and Program Review; and Wildland and Prescribed Fire Management Policy and Implementation Procedures Reference Guide. This current plan incorporates changes resulting from new policies on the national level as well as significant changes to available resources and other emerging issues, and replaces BNL's Wildland FMP dated 2014.

  12. Preparative radiation chemistry

    International Nuclear Information System (INIS)

    Drawe, H.

    1978-01-01

    Preparative synthesis of compounds with the aid of radiation chemistry is increasingly used in laboratories as well as on a technical scale. A large number of new compounds has been produced with the methods of radiation chemistry. With the increasing number of available radiation sources, also the number of synthesis metods in radiation chemistry has increased. This paper can only briefly mention the many possible ways of synthesis in radiation chemistry. (orig./HK) [de

  13. USSR Report Chemistry

    National Research Council Canada - National Science Library

    1986-01-01

    THIS REPORT CONTAINS FOREIGN MEDIA INFORMATION FROM THE USSR CONCERNING Adsorption, Alkaloids, ANALYTICAL CHEMISTRY, CATALYSIS, ELECTROCHEMISTRY, Fertilizers, INORGANIC COMPOUNDS, ORGANOPHOSPHOROUS...

  14. Frontiers in Gold Chemistry

    OpenAIRE

    Ahmed A. Mohamed

    2015-01-01

    Basic chemistry of gold tells us that it can bond to sulfur, phosphorous, nitrogen, and oxygen donor ligands. The Frontiers in Gold Chemistry Special Issue covers gold complexes bonded to the different donors and their fascinating applications. This issue covers both basic chemistry studies of gold complexes and their contemporary applications in medicine, materials chemistry, and optical sensors. There is a strong belief that aurophilicity plays a major role in the unending applications of g...

  15. Organic chemistry experiment

    International Nuclear Information System (INIS)

    Mun, Seok Sik

    2005-02-01

    This book deals with organic chemistry experiments, it is divided five chapters, which have introduction, the way to write the experiment report and safety in the laboratory, basic experiment technic like recrystallization and extraction, a lot of organic chemistry experiments such as fischer esterification, ester hydrolysis, electrophilic aromatic substitution, aldol reaction, benzoin condensation, wittig reaction grignard reaction, epoxidation reaction and selective reduction. The last chapter introduces chemistry site on the internet and way to find out reference on chemistry.

  16. Occupational exposure to polybrominated diphenyl ethers (PBDEs) and other flame retardant foam additives at gymnastics studios: Before, during and after the replacement of pit foam with PBDE-free foams.

    Science.gov (United States)

    Ceballos, Diana M; Broadwater, Kendra; Page, Elena; Croteau, Gerry; La Guardia, Mark J

    2018-07-01

    Coaches spend long hours training gymnasts of all ages aided by polyurethane foam used in loose blocks, mats, and other padded equipment. Polyurethane foam can contain flame retardant additives such as polybrominated diphenyl ethers (PBDEs), to delay the spread of fires. However, flame retardants have been associated with endocrine disruption and carcinogenicity. The National Institute for Occupational Safety and Health (NIOSH) evaluated employee exposure to flame retardants in four gymnastics studios utilized by recreational and competitive gymnasts. We evaluated flame retardant exposure at the gymnastics studios before, during, and after the replacement of foam blocks used in safety pits with foam blocks certified not to contain several flame retardants, including PBDEs. We collected hand wipes on coaches to measure levels of flame retardants on skin before and after their work shift. We measured flame retardant levels in the dust on window glass in the gymnastics areas and office areas, and in the old and new foam blocks used throughout the gymnastics studios. We found statistically higher levels of 9 out of 13 flame retardants on employees' hands after work than before, and this difference was reduced after the foam replacement. Windows in the gymnastics areas had higher levels of 3 of the 13 flame retardants than windows outside the gymnastics areas, suggesting that dust and vapor containing flame retardants became airborne. Mats and other padded equipment contained levels of bromine consistent with the amount of brominated flame retardants in foam samples analyzed in the laboratory. New blocks did not contain PBDEs, but did contain the flame retardants 2-ethylhexyl 2,3,4,5-tetrabromobenzoate and 2-ethylhexyl 2,3,4,5-tetrabromophthalate. We conclude that replacing the pit foam blocks eliminated a source of PBDEs, but not 2-ethylhexyl 2,3,4,5-tetrabromobenzoate and 2-ethylhexyl 2,3,4,5-tetrabromophthalate. We recommend ways to further minimize employee exposure

  17. WebFIRE

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Factor Information Retrieval (FIRE) Data System is a database management system containing EPA's recommended emission estimation factors for criteria and...

  18. Fire safety engineering

    International Nuclear Information System (INIS)

    Smith, D.N.

    1989-01-01

    The periodic occurrence of large-scale, potentially disastrous industrial accidents involving fire in hazardous environments such as oilwell blowouts, petrochemical explosions and nuclear installations highlights the need for an integrated approach to fire safety engineering. Risk reduction 'by design' and rapid response are of equal importance in the saving of life and property in such situations. This volume of papers covers the subject thoroughly, touching on such topics as hazard analysis, safety design and testing, fire detection and control, and includes studies of fire hazard in the context of environment protection. (author)

  19. Modeling of compartment fire

    International Nuclear Information System (INIS)

    Sathiah, P.; Siccama, A.; Visser, D.; Komen, E.

    2011-01-01

    Fire accident in a containment is a serious threat to nuclear reactors. Fire can cause substantial loss to life and property. The risk posed by fire can also exceed the risk from internal events within a nuclear reactor. Numerous research efforts have been performed to understand and analyze the phenomenon of fire in nuclear reactor and its consequences. Modeling of fire is an important subject in the field of fire safety engineering. Two approaches which are commonly used in fire modeling are zonal modeling and field modeling. The objective of this work is to compare zonal and field modeling approach against a pool fired experiment performed in a well-confined compartment. Numerical simulations were performed against experiments, which were conducted within PRISME program under the framework of OECD. In these experiments, effects of ventilation flow rate on heat release rate in a confined and mechanically ventilated compartment is investigated. Time dependent changes in gas temperature and oxygen mass fraction were measured. The trends obtained by numerical simulation performed using zonal model and field model compares well with experiments. Further validation is needed before this code can be used for fire safety analyses. (author)

  20. Synergistic Effect of Nanosilica Aerogel with Phosphorus Flame Retardants on Improving Flame Retardancy and Leaching Resistance of Wood

    Directory of Open Access Journals (Sweden)

    Xiaodan Zhu

    2014-01-01

    Full Text Available Nanosilica (Nano-SiO2 sol fabricated by a sol-gel process was introduced into wood modification with phosphorus flame retardants to improve the flame retardancy and leaching resistance of wood. The obtained materials were characterized by scanning electron microscopy and energy dispersive spectrometer (SEM-EDS, thermogravimetric analysis (TGA, cone calorimetric (CONE, and infrared spectroscopy (FT-IR. The residual rate of flame retardants before and after leaching was determinated by a leaching resistance. The results showed that the phosphorus flame retardants and SiO2 sol could reside in the poplar wood and are widely distributed in the vessels, pits, wood timber, and the spaces between wood cells of poplar substrate. TGA and CONE results indicated that the introduction of nano-SiO2 aerogel with phosphorus flame retardants had a significantly synergistic effect on improving the flame retardancy and inhibiting the release of smoke and toxic gases. In addition, the leaching resistance test, combined with infrared analysis and EDS analysis, confirmed that the phosphorus flame retardants were able to be fixed by SiO2 aerogel in the wood.

  1. Analytical chemistry instrumentation

    International Nuclear Information System (INIS)

    Laing, W.R.

    1986-01-01

    In nine sections, 48 chapters cover 1) analytical chemistry and the environment 2) environmental radiochemistry 3) automated instrumentation 4) advances in analytical mass spectrometry 5) fourier transform spectroscopy 6) analytical chemistry of plutonium 7) nuclear analytical chemistry 8) chemometrics and 9) nuclear fuel technology

  2. Fundamentals of nuclear chemistry

    International Nuclear Information System (INIS)

    Majer, V.

    1982-01-01

    The author of the book has had 25 years of experience at the Nuclear Chemistry of Prague Technical University. In consequence, the book is intended as a basic textbook for students of this field. Its main objectives are an easily understandable presentation of the complex subject and in spite of the uncertainty which still characterizes the definition and subjects of nuclear chemistry - a systematic classification and logical structure. Contents: 1. Introduction (history and definition); 2. General nuclear chemistry (physical fundamentals, hot atom chemistry, interaction of nuclear radiation with matter, radioactive elements, isotope effects, isotope exchange, chemistry of radioactive trace elements); 3. Methods of nuclear chemistry of nuclear chemistry (radiochemical methods, activation, separation and enrichment chemistry); 4. Preparative nuclear chemistry (isotope production, labelled compounds); 5. Analytival nuclear chemistry; 6. Applied nuclear chemistry (isotope applications in general physical and analytical chemistry). The book is supplemented by an annex with tables, a name catalogue and a subject index which will facilitate access to important information. (RB) [de

  3. Flammability of Cellulose-Based Fibers and the Effect of Structure of Phosphorus Compounds on Their Flame Retardancy

    Directory of Open Access Journals (Sweden)

    Khalifah A. Salmeia

    2016-08-01

    Full Text Available Cellulose fibers are promoted for use in various textile applications due their sustainable nature. Cellulose-based fibers vary considerably in their mechanical and flammability properties depending on their chemical composition. The chemical composition of a cellulose-based fiber is further dependent on their source (i.e., seed, leaf, cane, fruit, wood, bast, and grass. Being organic in nature, cellulose fibers, and their products thereof, pose considerable fire risk. In this work we have compared the flammability properties of cellulose fibers obtained from two different sources (i.e., cotton and peat. Compared to cotton cellulose textiles, peat-based cellulose textiles burn longer with a prominent afterglow which can be attributed to the presence of lignin in its structure. A series of phosphoramidates were synthesized and applied on both cellulose textiles. From thermogravimetric and pyrolysis combustion flow analysis of the treated cellulose, we were able to relate the flame retardant efficacy of the synthesized phosphorus compounds to their chemical structure. The phosphoramidates with methyl phosphoester groups exhibited higher condensed phase flame retardant effects on both types of cellulose textiles investigated in this study. In addition, the bis-phosphoramidates exhibited higher flame retardant efficacy compared to the mono-phosphoramidates.

  4. Brominated flame retardants in end-of-life management not problematic regarding formation of brominated dioxins/furans (PBDD/F)

    Energy Technology Data Exchange (ETDEWEB)

    Drohmann, D. [Great Lakes Chemical, Bergisch Gladbach (Germany); Tange, L. [Eurobrom B.V., Rijswijk (Netherlands); Rothenbacher, K. [Bromine Science and Environmental Forum, Brussels (Belgium)

    2004-09-15

    Bromine is used as the building block for some of the most effective flame retarding agents available to the plastics industry today. They are used to protect against the risk of accidental fires in a wide range of products. Brominated flame retardants (BFRs), as all flame retardants, act to decrease the risk of fire by increasing the fire resistance of the materials in which they are applied. There is a perception that BFRs affect adversely the end-of-life management of plastics through formation of brominated dioxins and furans (PBDD/F). In fact, there exists a wide range of data and practical experience demonstrating that the end-of-life management of plastics containing BFRs are fully compliant with legislation setting the strictest limit values for PBDD/F and is fully compatible with an integrated waste management concept. Furthermore, all existing EU Risk Assessments on BFRs according to the European Existing Substance Regulations include an assessment of the potential formation of dioxins and furans. All assessments conclude that the risks along the life-cycle of the chemicals for human health and the environment associated with the potential formation of PBDD/F are negligible. Moreover, two recent Swedish studies found, that consumer products with BFRs emit less pollutants than the same products without any FRs. This paper summarises available studies and presents the latest results regarding potential formation of brominated dioxins and furans in end-of-life management of plastics containing brominated flame retardants. Additionally, before BFR products enter the market they are tested for PBDD/F according to the ''German Dioxin Ordinance''. Depending on the substitution pattern the limit values for PBDD/F are set at <1{mu}g/kg (ppb) respectively <5{mu}g/kg (ppb).

  5. Plasma diagnostics with a retarding potential analyzer

    International Nuclear Information System (INIS)

    Jack, T.M.

    1996-01-01

    The plasma rocket is located at NASA Johnson Space Center. To produce a thrust in space, an inert gas is ionized into a plasma and heated in the linear section of a tokamak fusion device. The magnetic field used to contain the plasma has a magnitude of 2--10 kGauss. The plasma plume has a variable thrust and specific impulse. A high temperature retarding potential analyzer (RPA) is being developed to characterize the plasma in the plume and at the edge of the magnetically contained plasma. The RPA measures the energy and density of ions or electrons entering into its solid angle of collection. An oscilloscope displays the ion flux versus the collected current. All measurements are made relative to the facility ground. Testing of this device involves the determination of its output parameters, sensitivity, and responses to a wide range of energies and densities. Each grid will be tested individually by changing only its voltage and observing the output from the RPA. To verify that the RPA is providing proper output, it is compared to the output from a Langmuir or Faraday probe

  6. Alpha thalassaemia-mental retardation, X linked

    Directory of Open Access Journals (Sweden)

    Gibbons Richard

    2006-05-01

    Full Text Available Abstract X-linked alpha thalassaemia mental retardation (ATR-X syndrome in males is associated with profound developmental delay, facial dysmorphism, genital abnormalities and alpha thalassaemia. Female carriers are usually physically and intellectually normal. So far, 168 patients have been reported. Language is usually very limited. Seizures occur in about one third of the cases. While many patients are affectionate with their caregivers, some exhibit autistic-like behaviour. Patients present with facial hypotonia and a characteristic mouth. Genital abnormalities are observed in 80% of children and range from undescended testes to ambiguous genitalia. Alpha-thalassaemia is not always present. This syndrome is X-linked recessive and results from mutations in the ATRX gene. This gene encodes the widely expressed ATRX protein. ATRX mutations cause diverse changes in the pattern of DNA methylation at heterochromatic loci but it is not yet known whether this is responsible for the clinical phenotype. The diagnosis can be established by detection of alpha thalassaemia, identification of ATRX gene mutations, ATRX protein studies and X-inactivation studies. Genetic counselling can be offered to families. Management is multidisciplinary: young children must be carefully monitored for gastro-oesophageal reflux as it may cause death. A number of individuals with ATR-X are fit and well in their 30s and 40s.

  7. The needs of the retarded adult.

    Science.gov (United States)

    Armour, W E

    1979-11-01

    This article deals primarily with the needs of people with a degree of mental retardation, from mild to moderately severe, who are able to live approximately normal lives with assistance by counselling, advice and family help.It has been found that they do much better living in the community, mixing with normal people, but also with access to the company of persons similarly affected. With adequate advice and counselling, they can become self-sustaining in a number of ways, such as self care, living in their own homes or in small groups, and working either in sheltered employment or in the labor force. Their needs, like those of all others, range from the material such as shelter, food, clothing, possessions, transportation, health care, through the pyschological such as self fulfillment, recreation and enjoyment, love, affection and sex, and social such as legal protection and responsibility. With appropriate arrangements, these needs can be better met in community living, probably at less cost than if they were living in the traditional large institutions. Continued training and rehabilitative measures can often improve their abilities to an astonishing degree. They are rarely unteachable.

  8. Oral rehabilitation and management of mentally retarded.

    Science.gov (United States)

    Solanki, Jitender; Khetan, Jitendra; Gupta, Sarika; Tomar, Deepak; Singh, Meenakshi

    2015-01-01

    High level of periodontal problems of dental caries are frequently observed in mentally handicapped children. This group of patients presents various problems when they face dental treatments. Identification of such population and providing them affordable oral health care is the new concept. A systematic method for identification and screening of persons with mental retardation has been developed and is being followed. Cost and fear are the most commonly cited barriers to dental care. Physical or mental may lead to deterioration in self-care, and oral care state have a low priority. Risk factors are inter-related and are often barriers to oral health. With advancements in today's world sufficient information and support is available for each and every individual to lead a healthy life which include the access to the oral health care. Factors such as fear, anxiety and dental phobia plays a vital role in acceptance of dental care and also the delaying of dental care. Lack of knowledge of oral and dental disease, awareness or oral need, oral side-effects of medication and organization of dental services are highlighted in the literature. All health personnel should receive training to support the concept of primary oral health care. Training about dealing with such mentally handicapped people should be addressed urgently among the health professionals.

  9. Radionuclide transport and retardation in tuff

    International Nuclear Information System (INIS)

    Vine, E.N.; Bayhurst, B.P.; Daniels, W.R.; DeVilliers, S.J.; Erdal, B.R.; Lawrence, F.O.; Wolfsberg, K.

    1980-01-01

    Batch measurements provide an understanding of which experimental variables are important. For example, sorption ratios vary little with particle size (and surface area); however, groundwater composition and rock composition are quite important. A general correlation has been identified between mineralogy (major phases) and degree of sorption for strontium, cesium, and barium. Although these are approximate, a more detailed analysis may be possible as more samples are studied and the data base increased. Data from crushed tuff columns indicate that, except in simple cases where sorption coefficients are relatively low, and ion-exchange equilibria not only exist but are the dominant mechanism for removal of radioisotopes from solution, the simple relation between the sorption ratio R/sub d/ (or K/sub d/) and the relative velocity of radionuclides with respect to groundwater velocity may be insufficient to permit accurate modeling of the retardation of radionuclides. Additional work on whole core columns and larger blocks of intact material is required to better understand radionuclide sorption and transport through rock

  10. Some plant extracts retarde nitrification in soil

    Directory of Open Access Journals (Sweden)

    Abdul–Mehdi S. AL-ANSARI

    2015-12-01

    Full Text Available An incubation experiment was conducted to evaluate the effect of aqueous extracts of 17 plant materials on nitrification inhibition of urea- N in soil as compared with chemical inhibitor Dicyandiamide (DCD. Plant materials used in study were collected from different areas of Basrah province, south of Iraq. Aqueous extracts were prepared at ratio of 1:10 (plant material: water and added at conc. of 0.05, 0.10 and 0.20 ml g– 1 soil to loamy sand soil. DCD was added to soil at rate of 50 µg g-1 soil . Soil received urea at rate of 1000 µg N g-1 soil. Treated soils were incubated at 30 OC for 40 days. Results showed that application of all plant extracts, except those of casuarina, date palm and eucalyptus to soil retarded nitrification in soil. Caper, Sowthistle ,bladygrass and pomegranate extracts showed highest inhibition percentage (51, 42, 40 and 40 %, respectively and were found to be more effective than DCD (33 %. Highest inhibition was achieved by using those extracts at conc. of 0.1 ml g-1 soil after 10 days of incubation . Data also revealed that treated soil with these plant extracts significantly increased amount of NH4+–N and decreased amount of NO3-–N accumulation in soil compared with DCD and control treatments. Results of the study suggested a possibility of using aqueous extracts of some studied plants as potent nitrification inhibitor in soil.

  11. Silica Treatments: A Fire Retardant Strategy for Hemp Fabric/Epoxy Composites

    OpenAIRE

    Branda, Francesco; Malucelli, Giulio; Durante, Massimo; Piccolo, Alessandro; Mazzei, Pierluigi; Costantini, Aniello; Silvestri, Brigida; Pennetta, Miriam; Bifulco, Aurelio

    2016-01-01

    In this paper, for the first time, inexpensive waterglass solutions are exploited as a new, simple and ecofriendly chemical approach for promoting the formation of a silica-based coating on hemp fabrics, able to act as a thermal shield and to protect the latter from heat sources. Fourier Transform Infrared (FTIR) and solid-state Nuclear Magnetic Resonance (NMR) analysis confirm the formation of –C–O–Si– covalent bonds between the coating and the cellulosic substrate. The proposed waterglass t...

  12. Nonflammable Crew Clothing Utilizing Phosphorus-Based Fire-Retardant Materials, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — For maintaining U.S. leadership in space exploration, there is an urgent need to develop nonflammable crew clothing with the requirements of comfort, ease of...

  13. Non-Flammable Crew Clothing Utilizing Phosphorus-Based Fire Retardant Polymers, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — For maintaining U.S. leadership role in space exploration, there is an urgent need to develop non-flammable shirts, shorts, sweaters, and jackets without...

  14. Oil well fire extinguisher having upper and lower external flame retardant-dispersing rings

    International Nuclear Information System (INIS)

    Kim, H.S.

    1992-01-01

    This patent describes an extinguisher system for extinguishing flames from combustible fluid exiting from a pipe. It comprises an elongated tubular extinguisher body disposable over the combustible fluid emitting pipe; valve means mounted in the extinguisher body adjacent the upper outlet end for eliminating the flow of the combustion

  15. Using of Coating Technique by Inorganic Flame Retardants to Protect Civil and Industrial Foundations from Fires

    OpenAIRE

    Ali J. Salaman; Abbas A. Mahmood; Ali I. Al-Mosawi; Naser A.Alwash

    2011-01-01

    ?? ?? ??? ????? ????? ????? ?????? ?????? ??????? ??????? ????????? ??????? ?? ?????? ????????? ?????????? ???????? ??????? ???????? ??????? ????? ????? ????? ?? ???? ????? ????? . ?????? ???? ??????? ????????? ????? ???? ???? (3mm) ?????? ?????? ???? ??????? ????? ??? ????? ?????? ???? (SIROPOL 8340-PI) ?????? ?????? ????? ????? ?? ????? ????? ???????? ?????? ??????(49) (º 0 -º 45) ? ???????? ??? ??? ????? ????? ?? ????? ????? ???? ??????? (2000ºC) ???????? ???? ??????(20mm,15...

  16. American Association for Clinical Chemistry

    Science.gov (United States)

    ... Find the answer to your question IN CLINICAL CHEMISTRY Hs-cTnI as a Gatekeeper for Further Cardiac ... Online Harmonization.net Commission on Accreditation in Clinical Chemistry American Board of Clinical Chemistry Clinical Chemistry Trainee ...

  17. Research field of fire technology in Finland

    Science.gov (United States)

    Loikkanen, P.; Holm, C.

    1987-02-01

    The goal of the study is to give an overview of the whole diversified research field of fire technology and its problems. For this reason the research subjects have been grouped so that the responsibilities of different authorities, the legislation and specifications, various fields of technology, areas of industry, and groups of products could all be found as clearly as possible. The field has been divided into nine sub-areas. They are: general grounds, fire physics and chemistry, structural fire prevention, textiles and furnishings, devices for heating and other use, detection, fire fighting and rescue, quality control, and special problems. The sub-areas have been divided into 34 main subjects and these, excluding those of special problems, further into as many as 117 subject groups. Characteristics and problems of the sub-areas and the main subjects have been described. The subject groups have been characterized by key words and concepts which outline the projects. No concrete research projects and programs have, however, been directly suggested because their extent and contents depend essentially on financing and other available resources.

  18. Smoking and Home Fire Safety

    Science.gov (United States)

    ... Materials Working with the Media Fire Protection Technology Smoking fire safety outreach materials As a member of ... Not reported 7% In transport 1% 195 incidents Smoking fire safety messages to share It is important ...

  19. The New Color of Chemistry: Green Chemistry

    Directory of Open Access Journals (Sweden)

    Zuhal GERÇEK

    2012-01-01

    Full Text Available Green chemistry which is the new application of chemistry rules provides solutions to problems that mankind is faced with climate changes, sustainable agriculture, energy, toxics, depletion of natural sources e.g. designing new chemicals and processes that production and utilization of hazardous matters. So, it is the indispensible tool for sustainable development. Current and future chemists should consider the human health and ecological issues in their professional life. In order to provide a solution for this requirement, green chemistry rules and under standings should be primarily taken in the university curriculum and at all educational levels.

  20. Assessing and Increasing Descriptive Communication Skills in Retarded Children

    Science.gov (United States)

    Longhurst, Thomas M.

    1972-01-01

    The purpose of the paper was to review the impact of recent developments in research methodology with specific reference to the assessment and habilitation of communication problems in retarded children. (Author)

  1. Horticultural Careers for Persons with Mental Retardation. Expanding Opportunities.

    Science.gov (United States)

    Dehart-Bennett, Mary E.; Relf, Diane

    1990-01-01

    Horticulture careers provide therapeutic, rewarding employment for persons with mental retardation. Rehabilitation experts should become aware of the potential employment opportunities in horticulture so that individuals with disabilities can receive the training and job placement support they need. (Author)

  2. Persistence, bioaccumulation and toxicity of halogen-free flame retardants.

    NARCIS (Netherlands)

    Waaijers, S.L.; Kong, D; Hendriks, H.S.; de Wit, C.A.; Cousins, I.T.; Westerink, R.H.S.; Leonards, P.E.G.; Kraak, M.H.S.; Admiraal, W.; de Voogt, P.; Parsons, J.R.

    2013-01-01

    Polymers are synthetic organic materials that have a high carbon and hydrogen content, which renders them readily combustible. When used in buildings, electrical appliances, furniture, textiles, transportation, mining, and in many other applications, polymers have to fulfill flame retardancy

  3. Organophosphorous flame retardants in biota from Svalbard, Norway

    NARCIS (Netherlands)

    Hallanger, I.G.; Sagerup, K.; Evenset, A.; Kovacs, K.M.; Leonards, P.E.G.; Fuglei, E.; Routti, H.; Aars, J.; Strom, H.; Lydersen, C.; Gabrielsen, G. W.

    2015-01-01

    Eight arctic species, including fish, birds and mammals, from diverse habitats (marine and terrestrial) within the Svalbard Archipelago, Norway, were screened for 14 organophosphorus flame retardant (PFR) compounds. Ten PFRs were detected: tris(2-chloroethyl)phosphate (TCEP),

  4. Psychosocial Impacts of Mentally Retarded Children on Parents in ...

    African Journals Online (AJOL)

    Psychosocial Impacts of Mentally Retarded Children on Parents in Sudan. ... the age, number of handicapped children in the family as well as the degree of mental ... Results and discussion: The parents reported different psychological effects ...

  5. Etiological Study of Mental Retardation in Budapest, Hungary.

    Science.gov (United States)

    Czeizel, A.; And Others

    1980-01-01

    The first complex etiological study of mental retardation in Budapest was carried out with 1,364 children ages 7 to 14 years. Results are compared with findings from previous surveys in the United States and the United Kingdom. (Author)

  6. [Associated factors in newborns with intrauterine growth retardation].

    Science.gov (United States)

    Thompson-Chagoyán, Oscar C; Vega-Franco, Leopoldo

    2008-01-01

    To identify the risk factors implicated in the intrauterine growth retardation (IUGR) of neonates born in a social security institution. Case controls design study in 376 neonates: 188 with IUGR (weight RCIU in the population.

  7. Tourette syndrome, growth retardation, and platyspondyly: an entity?

    NARCIS (Netherlands)

    Scheper, Frederike Y.; Hennekam, Raoul C. M.

    2002-01-01

    A 14-year-old male is described with Tourette syndrome, platyspondyly, a marked delay in bone age, growth retardation that is more expressed in the limbs and talipes equinovarus. This appears to be a new entity

  8. Fatigue crack growth retardation in spot heated mild steel sheet

    Indian Academy of Sciences (India)

    Unknown

    Department of Metallurgical Engineering, *Department of Applied Mechanics and Hydraulics, ... growth retardation increases with increasing level of overload as well as with ..... Suresh S 1996 Fatigue of materials (Cambridge: Cambridge.

  9. Crusted piloleiomyoma with mental retardation: A rare association

    Directory of Open Access Journals (Sweden)

    Kamboj Sangeeta

    2009-01-01

    Full Text Available Piloleiomyoma is an uncommon benign smooth muscle neoplasm arising from arrector pili muscle. It is clinically defined by the presence of solitary or multiple reddish brown, dome-shaped, smooth papules or nodules, ranging in size from a few millimeters to a centimeter. The patients are otherwise healthy; but mental retardation developing in some patients with multiple Piloleiomyomas has been emerging as an intriguing matter for analysis by the scientists. In this case report, a mentally retarded patient with Piloleiomyoma is described, who, besides the characteristic smooth and dome-shaped lesions on the anterolateral aspect of the dorsum of the right foot, had developed crusting on one of the largest lesions. The histopathological features were consistent with Piloleiomyoma. The occurrence of Piloleiomyoma in a mentally retarded child and its unusual crusted nature has been rarely reported. The association between Piloleiomyoma and mental retardation is further stressed in this case report.

  10. The Overjustification Effect in Retarded Children: Durability and Generalizability.

    Science.gov (United States)

    Ogilvie, Lee; Prior, Margot

    1982-01-01

    Generalizability and durability of the overjustification effect (on decline in intrinsic motivation due to the lack of rewards in behavior modification programs) were examined in 35 normal preschool children and 17 mental age-matched retarded children. (Author/SW)

  11. Acquired alopecia, mental retardation, short stature, microcephaly, and optic atrophy

    NARCIS (Netherlands)

    Hennekam, R. C.; Renckens-Wennen, E. G.

    1990-01-01

    We report on a female patient who had acquired total alopecia, short stature, microcephaly, optic atrophy, severe myopia, and mental retardation. A survey of published reports failed to show an identical patient, despite various similar cases

  12. Surface chemistry essentials

    CERN Document Server

    Birdi, K S

    2013-01-01

    Surface chemistry plays an important role in everyday life, as the basis for many phenomena as well as technological applications. Common examples range from soap bubbles, foam, and raindrops to cosmetics, paint, adhesives, and pharmaceuticals. Additional areas that rely on surface chemistry include modern nanotechnology, medical diagnostics, and drug delivery. There is extensive literature on this subject, but most chemistry books only devote one or two chapters to it. Surface Chemistry Essentials fills a need for a reference that brings together the fundamental aspects of surface chemistry w

  13. Fundamentals of reactor chemistry

    International Nuclear Information System (INIS)

    Akatsu, Eiko

    1981-12-01

    In the Nuclear Engineering School of JAERI, many courses are presented for the people working in and around the nuclear reactors. The curricula of the courses contain also the subject material of chemistry. With reference to the foreign curricula, a plan of educational subject material of chemistry in the Nuclear Engineering School of JAERI was considered, and the fundamental part of reactor chemistry was reviewed in this report. Since the students of the Nuclear Engineering School are not chemists, the knowledge necessary in and around the nuclear reactors was emphasized in order to familiarize the students with the reactor chemistry. The teaching experience of the fundamentals of reactor chemistry is also given. (author)

  14. Halogenated flame retardants in the Great Lakes environment.

    Science.gov (United States)

    Venier, Marta; Salamova, Amina; Hites, Ronald A

    2015-07-21

    Flame retardants are widely used industrial chemicals that are added to polymers, such as polyurethane foam, to prevent them from rapidly burning if exposed to a small flame or a smoldering cigarette. Flame retardants, especially brominated flame retardants, are added to many polymeric products at percent levels and are present in most upholstered furniture and mattresses. Most of these chemicals are so-called "additive" flame retardants and are not chemically bound to the polymer; thus, they migrate from the polymeric materials into the environment and into people. As a result, some of these chemicals have become widespread pollutants, which is a concern given their possible adverse health effects. Perhaps because of their environmental ubiquity, the most heavily used group of brominated flame retardants, the polybrominated diphenyl ethers (PBDEs), was withdrawn from production and use during the 2004-2013 period. This led to an increasing demand for other flame retardants, including other brominated aromatics and organophosphate esters. Although little is known about the use or production volumes of these newer flame retardants, it is evident that some of these chemicals are also becoming pervasive in the environment and in humans. In this Account, we describe our research on the occurrence of halogenated and organophosphate flame retardants in the environment, with a specific focus on the Great Lakes region. This Account starts with a short introduction to the first generation of brominated flame retardants, the polybrominated biphenyls, and then presents our measurements of their replacement, the PBDEs. We summarize our data on PBDE levels in babies, bald eagles, and in air. Once these compounds came off the market, we began to measure several of the newer flame retardants in air collected on the shores of the Great Lakes once every 12 days. These new measurements focus on a tetrabrominated benzoate, a tetrabrominated phthalate, a hexabrominated diphenoxyethane

  15. In vitro screening of the endocrine disrupting potency of brominated flame retardants and their metabolites

    Energy Technology Data Exchange (ETDEWEB)

    Hamers, T.; Kamstra, J.H. [Inst. for Environmental Studies (IVM), Amsterdam (Netherlands); Sonneveld, E. [BioDetection Systems (BDS), Amsterdam (Netherlands); Murk, A.J. [Wageningen Univ., Toxicology Group, Wageningen (Netherlands); Zegers, B.N.; Boon, J.P. [Royal Netherlands Inst. for Sea Research (NIOZ), Den Burg (Netherlands); Brouwer, A. [Umea Univ., Umea (Sweden)

    2004-09-15

    Substantial evidence is recently becoming available that brominated flame retardants (BFRs) are potential endocrine disruptors. The toxicological profile of BFRs, however, is too incomplete and insufficient to perform human and ecological risk assessment. To fill these gaps, the EU funded research program FIRE was started in December 2002. This program aims at the identification and toxicological characterization of the most potent and environmentally relevant BFRs and their possible risk for human and wildlife health. As part of a hazard identification approach, twenty seven BFRs have been selected within the framework of FIRE for pre-screening their endocrinedisrupting potencies. Selection of test compounds was based on a maximal variation in physicochemical characteristics of BFRs within the test set, allowing the establishment of quantitative structure-activity relationships (QSARs). In addition, environmental relevance (e.g. high production volumes and persistence) and availability for testing were used as selection criteria. BFRs were tested in seven different in vitro bioassays for their potency to interfere via estrogenic, thyroidal, androgenic, progestagenic, and Ah-receptor mediated pathways. Metabolisation rates of BFRs were determined using phenobarbital-induced rat liver microsomes. Finally, the endocrine disrupting potency of the metabolites was determined in the same in vitro bio-assays and compared to the potency of the parent compounds.

  16. Studies on flame retardancy of radiation crosslinked PE foam

    International Nuclear Information System (INIS)

    Yang Huili; Yao Zhanhai; Xu Jun

    1996-01-01

    CPE, DBDPO and Sb 2 O 3 were used as flame-retardant of PE foam. Effect of CPE on PE foam under radiation and it's flame-retardancy were studied. The result showed that CPE can enhance radiation cross-linking of PE, and trinary of addition being made of CPE, DBDPO and Sb 2 O 3 made oxygen index of PE foam achieve over 30, and self-extinguish, it did not influence manufacture and mechanical properties of PE foam

  17. Determining trace element in hair of children with mental retardation

    International Nuclear Information System (INIS)

    Wang Zhilan; Gu Bomei; Jia Meixiang

    1992-01-01

    Seven trace elements in the hair come from 29 mental retardation children and 29 normal children have been analysed by INAA and XRF. There are significant differences for Fe and Sc between the two groups. The average value of Pb in the hair of the mental retardation children is higher than that of the normal children. Although Zn is very important for children growing, there is no significant difference between two children groups

  18. A Case with Mental Retardation, Gynecomastia and Dysmorphic Features

    Directory of Open Access Journals (Sweden)

    Ozge Ozalp Yuregir

    2012-03-01

    Full Text Available The 17 years old boy was diagnosed as Borjeson Forsmann Lehmann Syndrome who was referred to our Genetic Diagnosis Center for his dysmorphic features, obesity, gynecomasty and mental retardation . There are so many diseases in differantial diagnosis of obesity and mental retardation that BFLS is a rare one of them. We aimed to discuss the findings of the patient clinically diagnosed as BFLS within the scope of literature. [Cukurova Med J 2012; 37(1: 60-63

  19. A Case with Mental Retardation, Gynecomastia and Dysmorphic Features

    Directory of Open Access Journals (Sweden)

    Ozge Ozalp Yuregir

    2012-02-01

    Full Text Available The 17 years old boy was diagnosed as Borjeson Forsmann Lehmann Syndrome who was referred to our Genetic Diagnosis Center for his dysmorphic features, obesity, gynecomasty and mental retardation . There are so many diseases in differantial diagnosis of obesity and mental retardation that BFLS is a rare one of them. We aimed to discuss the findings of the patient clinically diagnosed as BFLS within the scope of literature. [Cukurova Med J 2012; 37(1.000: 60-63

  20. Retarded Boson–Fermion interaction in atomic systems

    Indian Academy of Sciences (India)

    WINTEC

    The retardation effect arises from the finite speed of light, and the fact that a virtual photon is always in transit. By separating the center of mass motion, a wave equa- tion that looks like the effective equation for only one spin-1/2 fermion is derived in §3. The retardation ef- fect can now be calculated to all orders. Separation ...

  1. Annual report 1985 Chemistry Department

    International Nuclear Information System (INIS)

    Funck, J.; Larsen, E.; Nielsen, O.J.

    1986-03-01

    This report contains a brief survey of the main activities in the Chemistry Department. All particles and reports published and lectures given in 1985 are presented. The facilities and equipment are mentioned briefly. The activities are divided into the following groups: radioisotope chemistry, analytical- and organic chemistry, environmental chemistry, polymer chemistry, geochemistry and waste disposal, radical chemistry, positron annihilation, mineral processing, and general. (author)

  2. Annual report 1984 Chemistry Department

    International Nuclear Information System (INIS)

    Funck, J.; Larsen, E.; Nielsen, O.J.

    1985-03-01

    This report contains a brief survey of the main activities in the Chemistry Department. All articles and reports published and lectures given in 1984 are presented. The facilities and equipment are mentioned briefly. The activities are divided into the following groups: radioisotope chemistry, analytical- and organic chemistry , environmental chemistry, polymer chemistry, geochemistry and waste disposal, radical chemistry, positron annihilation, mineral processing, and general. (author)

  3. Fundamentals of nuclear chemistry

    International Nuclear Information System (INIS)

    Matel, L.; Dulanska, S.

    2013-01-01

    This text-book is an introductory text in nuclear chemistry and radiochemistry, aimed on university undergraduate students in chemistry and related disciplines (physics, nuclear engineering). It covers the key aspects of modern nuclear chemistry. The text begins with basic theories in contemporary physics. It relates nuclear phenomena to key divisions of chemistry such as atomic structure, spectroscopy, equilibria and kinetics. It also gives an introduction to sources of ionizing radiation, detection of ionizing radiation, nuclear power industry and accident on nuclear installations as well as basic knowledge's of radiobiology. This book is essential reading for those taking a first course in nuclear chemistry and is a useful companion to other volumes in physical and analytical chemistry. It will also be of use to those new to working in nuclear chemistry or radiochemistry.

  4. The fire brigade renovates

    CERN Multimedia

    2002-01-01

    The new fire engine at CERN's Fire Station. A shiny brand-new fire engine is now attracting all the attention of the members of CERN's fire brigade. Since the beginning of last week this engine has taken over from an 18-year-old one, which has now been 'retired' from service. This modern vehicle, built in Brescia, Italy, is much lighter and more powerful than the old one and is equipped to allow the fire service to tackle most call-outs without the support of at least one other vehicle, as is currently necessary. The new fire engine is designed to transport six fire-fighters, 2000 litres of water, and is equipped not only for fire fighting actions but also to respond initially to any other kind of call-out, such as traffic accidents, chemical incidents, pollution, lightning, etc. It goes almost without saying that it is provided with the most modern safety measures, a low centre of gravity, as well as a special chassis and a combination pump (low and high pressure), which improve the safety and performance ...

  5. Fire exposed aluminium structures

    NARCIS (Netherlands)

    Maljaars, J.; Fellinger, J.E.J.; Soetens, F.

    2005-01-01

    Material properties and mechanical response models for fire design of steel structures are based on extensive research and experience. Contrarily, the behaviour of aluminium load bearing structures exposed to fire is relatively unexplored. This article gives an overview of physical and mechanical

  6. Advanced fire information system

    CSIR Research Space (South Africa)

    Frost, PE

    2007-01-01

    Full Text Available The South African Advanced Fire Information System (AFIS) is the first near real-time satellite-based fire monitoring system in Africa. It was originally developed for, and funded by, the electrical power utility Eskom, to reduce the impact of wild...

  7. Hot fire, cool soil

    NARCIS (Netherlands)

    Stoof, C.R.; Moore, D.; Fernandes, P.; Stoorvogel, J.J.; Fernandes, R.; Ferreira, A.J.D.; Ritsema, C.J.

    2013-01-01

    Wildfires greatly increase a landscape's vulnerability to flooding and erosion events by removing vegetation and changing soils. Fire damage to soil increases with increasing soil temperature, and, for fires where smoldering combustion is absent, the current understanding is that soil temperatures

  8. Autism and Mental Retardation of Young Children in China

    Institute of Scientific and Technical Information of China (English)

    XIN ZHANG; CHENG-YE JI

    2005-01-01

    Objective To understand the prevalence and rehabilitation status of autism and mental retardation in China. Methods Screening test and clinical assessment were conducted for the diagnosis of autism and mental retardation. The assessment included investigation of the histories of medical conditions and development of these two disorders, utilization and needs for the rehabilitation service, and related intellectual and behavioral appraisal. Results Among the 7345 children investigated, the prevalence of autism disorder was 1.10 cases per 1000 children aged 2-6 years (95% CI=0.34 to 2.54), and the prevalence of mental retardation was 10.76 cases per 1000 children (95% CI=8.40 to 13.12). All the children suffering from autistic disorder were intellectually disabled, whereas 31.0% of the non-autism mental retardates had other disabilities. The medical conditions prior to birth and perinatal period were important potential factors for autism. Half of the autistic children and 84% of the children with non-autism mental retardation had never received any rehabilitative service. Conclusions The prevalence of autistic disorder in children aged 2-6 years in Tianjin is rather high. It is urgent to improve the status of the autistic and intelligently disabled young children in China. In order to upgrade the level of early diagnostic and improve the intervention to autism and mental retardation, public awareness and training courses should be heightened.

  9. Unexplained mental retardation: is brain MRI useful?

    Energy Technology Data Exchange (ETDEWEB)

    Decobert, Fabrice; Merzoug, Valerie; Kalifa, Gabriel; Adamsbaum, Catherine [Saint Vincent de Paul Hospital, Department of Radiology, 75674 Paris Cedex 14 (France); Grabar, Sophie [Cochin Hospital, Department of Biostatistics and Medical Information, Paris (France); Ponsot, Gerard [Saint Vincent de Paul Hospital, Department of Neuropaediatrics, Paris (France); Des Portes, Vincent [Saint Vincent de Paul Hospital, Department of Neuropaediatrics, Paris (France); Debrousse Hospital, Department of Neuropaediatrics, Lyon (France)

    2005-06-01

    Mental retardation (MR), defined as an IQ below 70, is a frequent cause of consultation in paediatrics. To evaluate the yield of brain MRI in the diagnostic work-up of unexplained MR in children. Patients and methods: The MRI features and clinical data of 100 patients (age 1-18 years) affected with non-progressive MR of unknown origin were compared to an age-matched control group (n=100). Two radiologists conducted an independent review of the MRI scans. Univariate and multivariate analyses showed a higher incidence of brain anomalies in the MR group than in the control group (53 vs 17, OR=5.7 [2.9-11.1]), for signal abnormalities within the periventricular white matter (OR=20.3 [2.6-155.3]), lateral ventricular dilatation (OR=15.6 [2.0-124]), mild corpus callosum abnormalities (shortness, atrophy) (OR=6.8 [1.8-25.6]) and subtle cerebellar abnormalities, including fissure enlargement (OR=5.2 [1.1-26.2]). The diagnostic value of MRI abnormalities was considered good in 5% of patients (Alexander disease n=1, diffuse cortical malformation n=1, leukomalacia n=1, vermian agenesis n=1, commissural agenesis n=1), and weak in 48% of patients, in whom non-specific abnormalities did not lead to a diagnosis. Some clinical features resulted in a significantly higher percentage of abnormal MRI scans: abnormal neurological examination (82% vs 47%, P=0.008), abnormal skull circumference (66% vs 49%, P=0.04). Motor delay was associated with cerebellar abnormalities (P=0.01). (orig.)

  10. Unexplained mental retardation: is brain MRI useful?

    International Nuclear Information System (INIS)

    Decobert, Fabrice; Merzoug, Valerie; Kalifa, Gabriel; Adamsbaum, Catherine; Grabar, Sophie; Ponsot, Gerard; Des Portes, Vincent

    2005-01-01

    Mental retardation (MR), defined as an IQ below 70, is a frequent cause of consultation in paediatrics. To evaluate the yield of brain MRI in the diagnostic work-up of unexplained MR in children. Patients and methods: The MRI features and clinical data of 100 patients (age 1-18 years) affected with non-progressive MR of unknown origin were compared to an age-matched control group (n=100). Two radiologists conducted an independent review of the MRI scans. Univariate and multivariate analyses showed a higher incidence of brain anomalies in the MR group than in the control group (53 vs 17, OR=5.7 [2.9-11.1]), for signal abnormalities within the periventricular white matter (OR=20.3 [2.6-155.3]), lateral ventricular dilatation (OR=15.6 [2.0-124]), mild corpus callosum abnormalities (shortness, atrophy) (OR=6.8 [1.8-25.6]) and subtle cerebellar abnormalities, including fissure enlargement (OR=5.2 [1.1-26.2]). The diagnostic value of MRI abnormalities was considered good in 5% of patients (Alexander disease n=1, diffuse cortical malformation n=1, leukomalacia n=1, vermian agenesis n=1, commissural agenesis n=1), and weak in 48% of patients, in whom non-specific abnormalities did not lead to a diagnosis. Some clinical features resulted in a significantly higher percentage of abnormal MRI scans: abnormal neurological examination (82% vs 47%, P=0.008), abnormal skull circumference (66% vs 49%, P=0.04). Motor delay was associated with cerebellar abnormalities (P=0.01). (orig.)

  11. A Review of Fire Interactions and Mass Fires

    Directory of Open Access Journals (Sweden)

    Mark A. Finney

    2011-01-01

    Full Text Available The character of a wildland fire can change dramatically in the presence of another nearby fire. Understanding and predicting the changes in behavior due to fire-fire interactions cannot only be life-saving to those on the ground, but also be used to better control a prescribed fire to meet objectives. In discontinuous fuel types, such interactions may elicit fire spread where none otherwise existed. Fire-fire interactions occur naturally when spot fires start ahead of the main fire and when separate fire events converge in one location. Interactions can be created intentionally during prescribed fires by using spatial ignition patterns. Mass fires are among the most extreme examples of interactive behavior. This paper presents a review of the detailed effects of fire-fire interaction in terms of merging or coalescence criteria, burning rates, flame dimensions, flame temperature, indraft velocity, pulsation, and convection column dynamics. Though relevant in many situations, these changes in fire behavior have yet to be included in any operational-fire models or decision support systems.

  12. Fires in Chile

    Science.gov (United States)

    2002-01-01

    On February 5, 2002, the dense smoke from numerous forest fires stretched out over the Pacific Ocean about 400 miles south of Santiago, Chile. This true-color Moderate-resolution Imaging Spectroradiometer (MODIS) image shows the fires, which are located near the city of Temuco. The fires are indicated with red dots (boxes in the high-resolution imagery). The fires were burning near several national parks and nature reserves in an area of the Chilean Andes where tourism is very popular. Southeast of the fires, the vegetation along the banks of the Rio Negro in Argentina stands out in dark green. Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC

  13. Sodium fire protection

    International Nuclear Information System (INIS)

    Raju, C.; Kale, R.D.

    1979-01-01

    Results of experiments carried out with sodium fires to develop extinguishment techniques are presented. Characteristics, ignition temperature, heat evolution and other aspects of sodium fires are described. Out of the powders tested for extinguishment of 10 Kg sodium fires, sodium bi-carbonate based dry chemical powder has been found to be the best extinguisher followed by large sized vermiculite and then calcium carbonate powders distributed by spray nozzles. Powders, however, do not extinguish large fires effectively due to sodium-concrete reaction. To control large scale fires in a LMFBR, collection trays with protective cover have been found to cause oxygen starvation better than flooding with inert gas. This system has an added advantage in that there is no damage to the sodium facilities as has been in the case of powders which often contain chlorine compounds and cause stress corrosion cracking. (M.G.B.)

  14. Nuclear chemistry in the traditional chemistry program

    International Nuclear Information System (INIS)

    Kleppinger, E.W.

    1993-01-01

    The traditional undergraduate program for chemistry majors, especially at institutions devoted solely to undergraduate education, has limited space for 'special topics' courses in areas such as nuclear and radiochemistry. A scheme is proposed whereby the basic topics covered in an introductury radiochemistry course are touched upon, and in some cases covered in detail, at some time during the four-year sequence of courses taken by a chemistry major. (author) 6 refs.; 7 tabs

  15. The New Color of Chemistry: Green Chemistry

    OpenAIRE

    Zuhal GERÇEK

    2012-01-01

    Green chemistry which is the new application of chemistry rules provides solutions to problems that mankind is faced with climate changes, sustainable agriculture, energy, toxics, depletion of natural sources e.g. designing new chemicals and processes that production and utilization of hazardous matters. So, it is the indispensible tool for sustainable development. Current and future chemists should consider the human health and ecological issues in their professional life. In order to provid...

  16. Chlorinated organophosphate and “legacy” brominated flame retardants in UK waste soft furnishings: A preliminary study

    Directory of Open Access Journals (Sweden)

    William A. Stubbings

    2016-12-01

    Full Text Available The Furniture and Furnishings (Fire Safety Regulations 1988 is the major driver for the use of chemical flame retardants (FRs in soft furnishings marketed in the UK. While these regulations specify the level of flame retardancy required, they do not specify how such levels should be achieved. Consequently, it remains unclear which FRs are present in UK soft furnishings. This is important not only to help assess what FRs we may be exposed to currently, but which FRs are currently entering the waste stream with concomitant potential for release into the environment. To address this data gap, concentrations of polybrominated diphenyl ethers (PBDEs, hexabromocyclododecane (HBCDD and a range of chlorinated organophosphate flame retardants (OPFRs were measured in samples of domestic and office waste soft furnishings products entering the UK waste stream in 2011 and 2012. This preliminary study measured the FR content of: carpets (n = 4, curtains (n = 7, mattress fabrics (n = 2, furniture foam (n = 9, and furniture upholstery textiles (n = 10. Polybrominated diphenyl ethers (PBDEs and hexabromocyclododecane (HBCDD were not found at significant concentrations (below detection limits in most samples in any of the twenty two analysed products. In contrast, 7 of the 9 furniture foam samples were treated with tris(2-chloroisopropylphosphate (TCIPP at a mean concentration of 1.9% w/w, with another single foam sample containing tris(1,3-dichloroisopropylphosphate (TDCIPP and tris(2-chloroethylphosphate (TCEP at 1.1 and 0.5% respectively. By comparison, PBDE concentrations are within the range reported previously for UK indoor dust [18], rather than the percent by weight levels required to impart flame retardancy.

  17. USFA NFIRS 2005 Basic Fire Incident Data

    Data.gov (United States)

    Department of Homeland Security — The 2005 US Fire Administration Fire (USFA) Fire Incident & Cause Data was provided by the U.S. Fire Administration's (USFA) National Fire Data Center's (NFDC's)...

  18. USFA NFIRS 2008 Basic Fire Incident Data

    Data.gov (United States)

    Department of Homeland Security — The 2008 US Fire Administration Fire (USFA) Fire Incident & Cause Data was provided by the U.S. Fire Administration's (USFA) National Fire Data Center's (NFDC's)...

  19. Fire science at LLNL: A review

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, H.K. (ed.)

    1990-03-01

    This fire sciences report from LLNL includes topics on: fire spread in trailer complexes, properties of welding blankets, validation of sprinkler systems, fire and smoke detectors, fire modeling, and other fire engineering and safety issues. (JEF)

  20. USFA NFIRS 2009 Basic Fire Incident Data

    Data.gov (United States)

    Department of Homeland Security — The 2009 US Fire Administration Fire (USFA) Fire Incident & Cause Data was provided by the U.S. Fire Administration's (USFA) National Fire Data Center's (NFDC's)...