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Sample records for burn rate catalysts

  1. Development of ferrocene burning rate catalysts

    NASA Astrophysics Data System (ADS)

    Zhang, Ren; Li, Jianhua; Weng, Wujun

    1994-06-01

    In this paper, a comprehensive survey of the development of research on the ferrocene burning rate catalysts in the past thirty years was made. The development trend of ferrocene catalysts in the future was also pointed out.

  2. Synthesis of ethylene diamine-based ferrocene terminated dendrimers and their application as burning rate catalysts.

    PubMed

    Zain-Ul-Abdin; Wang, Li; Yu, Haojie; Saleem, Muhammad; Akram, Muhammad; Khalid, Hamad; Abbasi, Nasir M; Yang, Xianpeng

    2017-02-01

    Ferrocene-based derivatives are widely used as ferrocene-based burning rate catalysts (BRCs) for ammonium perchlorate (AP)-based propellant. However, in long storage, small ferrocene-based derivatives migrate to the surface of the propellant, which results in changes in the designed burning parameters and finally causes unstable combustion. To retard the migration of ferrocene-based BRCs in the propellant and to increase the combustion of the solid propellant, zero to third generation ethylene diamine-based ferrocene terminated dendrimers (0G, 1G, 2G and 3G) were synthesized. The synthesis of these dendrimers was confirmed by (1)H NMR and FT-IR spectroscopy. The electrochemical behavior of 0G, 1G, 2G and 3G was investigated by cyclic voltammetry (CV) and the burning rate catalytic activity of 0G, 1G, 2G and 3G on thermal disintegration of AP was examined by thermogravimetry (TG) and differential thermogravimetry (DTG) techniques. Anti-migration studies show that 1G, 2G and 3G exhibit improved anti-migration behavior in the AP-based propellant.

  3. Burning Rate Emulator

    NASA Image and Video Library

    The Burning Rate Emulator is a gas fuel investigation attempting to emulate the burning of solids to improve our understanding of materials''flammability over a wide range of conditions. The approa...

  4. PBXN-110 Burn Rate Estimate

    SciTech Connect

    Glascoe, E

    2008-08-11

    It is estimated that PBXN-110 will burn laminarly with a burn function of B = (0.6-1.3)*P{sup 1.0} (B is the burn rate in mm/s and P is pressure in MPa). This paper provides a brief discussion of how this burn behavior was estimated.

  5. High burn rate solid composite propellants

    NASA Astrophysics Data System (ADS)

    Manship, Timothy D.

    psia. In addition, DCPD propellant was shown to burn at twice the rate of HTPB propellant, most likely a result of its lower decomposition temperature. A high burn rate DCPD propellant was developed, but due to poor wetting, the resulting propellant was brittle and fragmented during strand burn testing. Lastly, GAP-plasticized DCPD gumstocks were not able to be produced most likely due to an interaction between GAP and the cure catalyst for DCPD.

  6. High-Pressure Burning Rate Studies of Solid Rocket Propellants

    DTIC Science & Technology

    2013-01-01

    fect of plasticizer, oxidizer particle size, catalyst , and binder type were investigated. 1 INTRODUCTION Increasing performance remains a principal...level of catalyst . Examination of the high -pressure burning of the catalyzed propellants was the intent of examining Propellants W and X; however, it is... HIGH -PRESSURE BURNING RATE STUDIES OF SOLID ROCKET PROPELLANTS A. I. Atwood, K.P. Ford, and C. J. Wheeler Naval Air Warfare Center Weapons Division 1

  7. Nitramine propellants. [gun propellant burning rate

    NASA Technical Reports Server (NTRS)

    Cohen, N. S.; Strand, L. D. (Inventor)

    1978-01-01

    Nitramine propellants without a pressure exponent shift in the burning rate curves are prepared by matching the burning rate of a selected nitramine or combination of nitramines within 10% of burning rate of a plasticized active binder so as to smooth out the break point appearance in the burning rate curve.

  8. Effect of crib dimensions on burning rate

    Treesearch

    S. McAllister; M. Finney

    2013-01-01

    The burning rate of unconfined cribs has long been identified to occur in two regimes: the densely-packed regime where the burning rate is proportional to the crib porosity and the loosely-packed regime where the burning rate is independent of porosity. Though the cribs used to define these burning regimes were primarily cubic in dimension, there are seemingly endless...

  9. Suppressants for lowering propellant binder burning rate

    NASA Technical Reports Server (NTRS)

    Thompson, W. W.

    1972-01-01

    Addition of boron compound to lower burning rate of solid propellant binder is reported. Chemical reactions involved in propellant binder modification are described. Advantages of method for lowering burning rate are analyzed.

  10. Acoustic emission strand burning technique for motor burning rate prediction

    NASA Technical Reports Server (NTRS)

    Christensen, W. N.

    1978-01-01

    An acoustic emission (AE) method is being used to measure the burning rate of solid propellant strands. This method has a precision of 0.5% and excellent burning rate correlation with both subscale and large rocket motors. The AE procedure burns the sample under water and measures the burning rate from the acoustic output. The acoustic signal provides a continuous readout during testing, which allows complete data analysis rather than the start-stop clockwires used by the conventional method. The AE method helps eliminate such problems as inhibiting the sample, pressure increase and temperature rise, during testing.

  11. Catalysts for lean burn engine exhaust abatement

    DOEpatents

    Ott, Kevin C.; Clark, Noline C.; Paffett, Mark T.

    2003-01-01

    The present invention provides a process for catalytically reducing nitrogen oxides in an exhaust gas stream containing nitrogen oxides and a reductant material by contacting the gas stream under conditions effective to catalytically reduce the nitrogen oxides with a catalyst comprising a aluminum-silicate type material and a minor amount of a metal, the catalyst characterized as having sufficient catalytic activity so as to reduce the nitrogen oxides by at least 60 percent under temperatures within the range of from about 200.degree. C. to about 400.degree. C.

  12. Catalysts For Lean Burn Engine Exhaust Abatement

    DOEpatents

    Ott, Kevin C.; Clark, Noline C.; Paffett, Mark T.

    2004-04-06

    The present invention provides a process for catalytically reducing nitrogen oxides in an exhaust gas stream containing nitrogen oxides and a reductant material by contacting the gas stream under conditions effective to catalytically reduce the nitrogen oxides with a catalyst comprising a aluminum-silicate type material and a minor amount of a metal, the catalyst characterized as having sufficient catalytic activity so as to reduce the nitrogen oxides by at least 60 percent under temperatures within the range of from about 200.degree. C. to about 400.degree. C.

  13. Catalysts for lean burn engine exhaust abatement

    DOEpatents

    Ott, Kevin C.; Clark, Noline C.; Paffett, Mark T.

    2006-08-01

    The present invention provides a process for catalytically reducing nitrogen oxides in an exhaust gas stream containing nitrogen oxides and a reductant material by contacting the gas stream under conditions effective to catalytically reduce the nitrogen oxides with a catalyst comprising a aluminum-silicate type material and a minor amount of a metal, the catalyst characterized as having sufficient catalytic activity so as to reduce the nitrogen oxides by at least 60 percent under temperatures within the range of from about 200.degree. C. to about 400.degree. C.

  14. Burning Rate Transitions for HMX Burned as a Binderless Propellant,

    DTIC Science & Technology

    1980-06-01

    have shown that the regression attains velocities up to 6000 cm/s at high pressure , with pressure exponents as low as 0.3, depending on sample...base of the charge, extremely high burn rate propellant (several thou- sand cm/s or more depending on gun pressure and muzzle velocity desired) is...experiments were carried out, the calculated flame heights range from 17 to 700 cm, depending on particle size and pressure . Thus, it is not surprising that

  15. High-pressure burning rate studies of solid rocket propellants

    NASA Astrophysics Data System (ADS)

    Atwood, A. I.; Ford, K. P.; Wheeler, C. J.

    2013-03-01

    Increased rocket motor performance is a major driver in the development of solid rocket propellant formulations for chemical propulsion systems. The use of increased operating pressure is an option to improve performance potentially without the cost of reformulation. A technique has been developed to obtain burning rate data across a range of pressures from ambient to 345 MPa. The technique combines the use of a low loading density combustion bomb with a high loading density closed bomb technique. A series of nine ammonium perchlorate (AP) based propellants were used to demonstrate the use of the technique, and the results were compared to the neat AP burning rate "barrier". The effect of plasticizer, oxidizer particle size, catalyst, and binder type were investigated.

  16. The Combustion of HMX. [burning rate at high pressures

    NASA Technical Reports Server (NTRS)

    Boggs, T. L.; Price, C. F.; Atwood, A. I.; Zurn, D. E.; Eisel, J. L.

    1980-01-01

    The burn rate of HMX was measured at high pressures (p more than 1000 psi). The self deflagration rate of HMX was determined from 1 atmosphere to 50,000 psi. The burning rate shows no significant slope breaks.

  17. The Combustion of HMX. [burning rate at high pressures

    NASA Technical Reports Server (NTRS)

    Boggs, T. L.; Price, C. F.; Atwood, A. I.; Zurn, D. E.; Eisel, J. L.

    1980-01-01

    The burn rate of HMX was measured at high pressures (p more than 1000 psi). The self deflagration rate of HMX was determined from 1 atmosphere to 50,000 psi. The burning rate shows no significant slope breaks.

  18. Effects of propellant composition variables on acceleration-induced burning-rate augmentation of solid propellants

    NASA Technical Reports Server (NTRS)

    Northam, G. B.

    1972-01-01

    This work was conducted to define further the effects of propellant composition variables on the acceleration-induced burning rate augmentation of solid propellants. The rate augmentation at a given acceleration was found to be a nonlinear inverse function of the reference burning rate and not controlled by binder or catalyst type at a given reference rate. A nonaluminized propellant and a low rate double-base propellant exhibited strong transient rate augmentation due to surface pitting resulting from the retention of hot particles on the propellant surface.

  19. Initial fuel temperature effects on burning rate of pool fire.

    PubMed

    Chen, Bing; Lu, Shou-Xiang; Li, Chang-Hai; Kang, Quan-Sheng; Lecoustre, Vivien

    2011-04-15

    The influence of the initial fuel temperature on the burning behavior of n-heptane pool fire was experimentally studied at the State Key Laboratory of Fire Science (SKLFS) large test hall. Circular pool fires with diameters of 100mm, 141 mm, and 200 mm were considered with initial fuel temperatures ranging from 290 K to 363 K. Burning rate and temperature distributions in fuel and vessel wall were recorded during the combustion. The burning rate exhibited five typical stages: initial development, steady burning, transition, bulk boiling burning, and decay. The burning rate during the steady burning stage was observed to be relatively independent of the initial fuel temperature. In contrast, the burning rate of the bulk boiling burning stage increases with increased initial fuel temperature. It was also observed that increased initial fuel temperature decreases the duration of steady burning stage. When the initial temperature approaches the boiling point, the steady burning stage nearly disappears and the burning rate moves directly from the initial development stage to the transition stage. The fuel surface temperature increases to its boiling point at the steady burning stage, shortly after ignition, and the bulk liquid reaches boiling temperature at the bulk boiling burning stage. No distinguished cold zone is formed in the fuel bed. However, boiling zone is observed and the thickness increases to its maximum value when the bulk boiling phenomena occurs.

  20. Effect of structure of energetic materials on burning rate

    SciTech Connect

    Fogelzang, A.E.; Sinditskii, V.P.; Egorshev, V.Y.; Serushkin, V.V.

    1996-07-01

    Data on the steady-state combustion in a constant-pressure bomb at 0.1--40 MPa are presented for energetic materials from the following classes: metal salts of organic explosive acids, salts of organic bases with inorganic oxidizing acids, explosive coordination compounds, and endothermic polynitrogen compounds. For combustion of salts of organic bases with oxidizing acids it has been found that an increase in the oxidant redox potential, whose value serves as an estimate of the oxidizer reactivity, causes the burning rate value to increase. The same tendency has been disclosed for explosive coordination compounds which can formally be considered as metal-containing analogs of the salts of organic bases with oxidizing acids. The introduction of a metal atom in an organic explosive acid has been shown to result generally in an enhancement of the burning rate, with the effectiveness of the metal as the combustion catalyst being dependent not only on the nature of the metal but on its position in the molecule as well. Neither the nature of the metal, nor the nature and structure of the ligand really affects the combustion of coordination compounds of metal azides, whose combustion occurs at the expense of the heat produced in the decomposition process. All the coordination azides seem to have the same rate-limiting stage, namely, the decomposition of the intermediate HN{sub 3} and differ from one another by their burning temperatures. The similar behavior is also characteristic of metalless analogs of the coordination azides: salts of HN{sub 3} with amines.

  1. Fuel droplet burning rates at high pressures.

    NASA Technical Reports Server (NTRS)

    Canada, G. S.; Faeth, G. M.

    1973-01-01

    Combustion of methanol, ethanol, propanol-1, n-pentane, n-heptane, and n-decane was observed in air under natural convection conditions, at pressures up to 100 atm. The droplets were simulated by porous spheres, with diameters in the range from 0.63 to 1.90 cm. The pressure levels of the tests were high enough so that near-critical combustion was observed for methanol and ethanol. Due to the high pressures, the phase-equilibrium models of the analysis included both the conventional low-pressure approach as well as high-pressure versions, allowing for real gas effects and the solubility of combustion-product gases in the liquid phase. The burning-rate predictions of the various theories were similar, and in fair agreement with the data. The high-pressure theory gave the best prediction for the liquid-surface temperatures of ethanol and propanol-1 at high pressure. The experiments indicated the approach of critical burning conditions for methanol and ethanol at pressures on the order of 80 to 100 atm, which was in good agreement with the predictions of both the low- and high-pressure analysis.

  2. Burning rates of wood cribs with implications for wildland fires

    Treesearch

    Sara McAllister; Mark Finney

    2016-01-01

    Wood cribs are often used as ignition sources for room fire tests and the well characterized burning rates may also have applications to wildland fires. The burning rate of wildland fuel structures, whether the needle layer on the ground or trees and shrubs themselves, is not addressed in any operational fire model and no simple model exists. Several relations...

  3. Aluminum Burn Rate Modifiers Based on Reactive Nanocomposite Powders (Preprint)

    DTIC Science & Technology

    2009-02-05

    Journal Article 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Aluminum Burn Rate Modifiers Based on Reactive Nanocomposite ...For publication in Propellants, Explosives, Pyrotechnics . 14. ABSTRACT Aluminum powders have long been used as additives in propellants, pyrotechnics ...and explosives. Aluminum has a high enthalpy of combustion but relatively low burn rate. Addition of reactive nanocomposite powders can increase

  4. Burning Rate Studies of HMX Propellants at High Pressures

    DTIC Science & Technology

    1975-03-01

    propellant burning should take place rather than HMX burning. The compounds selected for evaluation were: Melting Point Boiling Point (0C) (0 C) acetanilide ... Acetanilide and phenylsulfone, the two very la,, melting cxnpounds, greatly suppressed the KV exotherm peak (rigue 3). However, this change in the TV...Percent IM (Class A/E, 70/30), 2 Percent Additive] Phenyl Hydro- Additive None Acetanilide Anthracene Sulfone Quinone Pressure (Psi) Burning Rate @ 70

  5. High Pressure Burn Rate Measurements on an Ammonium Perchlorate Propellant

    SciTech Connect

    Glascoe, E A; Tan, N

    2010-04-21

    High pressure deflagration rate measurements of a unique ammonium perchlorate (AP) based propellant are required to design the base burn motor for a Raytheon weapon system. The results of these deflagration rate measurements will be key in assessing safety and performance of the system. In particular, the system may experience transient pressures on the order of 100's of MPa (10's kPSI). Previous studies on similar AP based materials demonstrate that low pressure (e.g. P < 10 MPa or 1500 PSI) burn rates can be quite different than the elevated pressure deflagration rate measurements (see References and HPP results discussed herein), hence elevated pressure measurements are necessary in order understand the deflagration behavior under relevant conditions. Previous work on explosives have shown that at 100's of MPa some explosives will transition from a laminar burn mechanism to a convective burn mechanism in a process termed deconsolidative burning. The resulting burn rates that are orders-of-magnitude faster than the laminar burn rates. Materials that transition to the deconsolidative-convective burn mechanism at elevated pressures have been shown to be considerably more violent in confined heating experiments (i.e. cook-off scenarios). The mechanisms of propellant and explosive deflagration are extremely complex and include both chemical, and mechanical processes, hence predicting the behavior and rate of a novel material or formulation is difficult if not impossible. In this work, the AP/HTPB based material, TAL-1503 (B-2049), was burned in a constant volume apparatus in argon up to 300 MPa (ca. 44 kPSI). The burn rate and pressure were measured in-situ and used to calculate a pressure dependent burn rate. In general, the material appears to burn in a laminar fashion at these elevated pressures. The experiment was reproduced multiple times and the burn rate law using the best data is B = (0.6 {+-} 0.1) x P{sup (1.05{+-}0.02)} where B is the burn rate in mm/s and

  6. OXIDATION OF MERCURY ACROSS SCR CATALYSTS IN COAL-FIRED POWER PLANTS BURNING LOW RANK FUELS

    SciTech Connect

    Constance Senior

    2004-12-31

    The objectives of this program were to measure the oxidation of mercury in flue gas across SCR catalyst in a coal-fired power plant burning low rank fuels using a slipstream reactor containing multiple commercial catalysts in parallel and to develop a greater understanding of mercury oxidation across SCR catalysts in the form of a simple model. The Electric Power Research Institute (EPRI) and Argillon GmbH provided co-funding for this program. REI used a multicatalyst slipstream reactor to determine oxidation of mercury across five commercial SCR catalysts at a power plant that burned a blend of 87% subbituminous coal and 13% bituminous coal. The chlorine content of the blend was 100 to 240 {micro}g/g on a dry basis. Mercury measurements were carried out when the catalysts were relatively new, corresponding to about 300 hours of operation and again after 2,200 hours of operation. NO{sub x}, O{sub 2} and gaseous mercury speciation at the inlet and at the outlet of each catalyst chamber were measured. In general, the catalysts all appeared capable of achieving about 90% NO{sub x} reduction at a space velocity of 3,000 hr{sup -1} when new, which is typical of full-scale installations; after 2,200 hours exposure to flue gas, some of the catalysts appeared to lose NO{sub x} activity. For the fresh commercial catalysts, oxidation of mercury was in the range of 25% to 65% at typical full-scale space velocities. A blank monolith showed no oxidation of mercury under any conditions. All catalysts showed higher mercury oxidation without ammonia, consistent with full-scale measurements. After exposure to flue gas for 2,200 hours, some of the catalysts showed reduced levels of mercury oxidation relative to the initial levels of oxidation. A model of Hg oxidation across SCRs was formulated based on full-scale data. The model took into account the effects of temperature, space velocity, catalyst type and HCl concentration in the flue gas.

  7. Advanced digital methods for solid propellant burning rate determination

    NASA Astrophysics Data System (ADS)

    Jones, Daniel A.

    The work presented here is a study of a digital method for determining the combustion bomb burning rate of a fuel-rich gas generator propellant sample using the ultrasonic pulse-echo technique. The advanced digital method, which places user defined limits on the search for the ultrasonic echo from the burning surface, is computationally faster than the previous cross correlation method, and is able to analyze data for this class of propellant that the previous cross correlation data reduction method could not. For the conditions investigated, the best fit burning rate law at 800 psi from the ultrasonic technique and advanced cross correlation method is within 3 percent of an independent analysis of the same data, and is within 5 percent of the best fit burning rate law found from parallel research of the same propellant in a motor configuration.

  8. OXIDATION OF MERCURY ACROSS SCR CATALYSTS IN COAL-FIRED POWER PLANTS BURNING LOW RANK FUELS

    SciTech Connect

    Constance Senior

    2004-10-29

    This is the seventh Quarterly Technical Report for DOE Cooperative Agreement No: DE-FC26-03NT41728. The objective of this program is to measure the oxidation of mercury in flue gas across SCR catalyst in a coal-fired power plant burning low rank fuels using a slipstream reactor containing multiple commercial catalysts in parallel. The Electric Power Research Institute (EPRI) and Argillon GmbH are providing co-funding for this program. This program contains multiple tasks and good progress is being made on all fronts. During this quarter, a model of Hg oxidation across SCRs was formulated based on full-scale data. The model took into account the effects of temperature, space velocity, catalyst type and HCl concentration in the flue gas.

  9. Burning rate of solid wood measured in a heat release rate calorimeter

    Treesearch

    H. C. Tran; R. H. White

    1992-01-01

    Burning rate is a key factor in modeling fire growth and fire endurance of wood structures. This study investigated the burning rate of selected wood materials as determined by heat release, mass loss and charring rates. Thick samples of redwood, southern pine, red oak and basswood were tested in a heat release rate calorimeter. Results on ignitability and average beat...

  10. A Burning Rate Emulator (BRE) for Study in Microgravity

    NASA Technical Reports Server (NTRS)

    Markan, A.; Sunderland, P. B.; Quintiere, J. G.; DeRis, J.; Stocker, D. P.

    2015-01-01

    A gas-fueled burner, the Burning Rate Emulator (BRE), is used to emulate condensed-phase fuel flames. The design has been validated to easily measure the burning behavior of condensed-phase fuels by igniting a controlled stream of gas fuel and diluent. Four properties, including the heat of combustion, the heat of gasification, the surface temperature, and the laminar smoke point, are assumed to be sufficient to define the steady burning rate of a condensed-phase fuel. The heat of gasification of the fuel is determined by measuring the heat flux and the fuel flow rate. Microgravity BRE tests in the NASA 5.2 s drop facility have examined the burning of pure methane and ethylene (pure and 50 in N2 balance). Fuel flow rates, chamber oxygen concentration and initial pressure have been varied. Two burner sizes, 25 and 50 mm respectively, are chosen to examine the nature of initial microgravity burning. The tests reveal bubble-like flames that increase within the 5.2s drop but the heat flux received from the flame appears to asymptotically approach steady state. Portions of the methane flames appear to locally detach and extinguish at center, while its shape remains fixed, but growing. The effective heat of gasification is computed from the final measured net heat flux and the fuel flow rate under the assumption of an achieved steady burning. Heat flux (or mass flux) and flame position are compared with stagnant layer burning theory. The analysis offers the prospect of more complete findings from future longer duration ISS experiments.

  11. Resistance of the boreal forest to high burn rates

    PubMed Central

    Héon, Jessie; Arseneault, Dominique; Parisien, Marc-André

    2014-01-01

    Boreal ecosystems and their large carbon stocks are strongly shaped by extensive wildfires. Coupling climate projections with records of area burned during the last 3 decades across the North American boreal zone suggests that area burned will increase by 30–500% by the end of the 21st century, with a cascading effect on ecosystem dynamics and on the boreal carbon balance. Fire size and the frequency of large-fire years are both expected to increase. However, how fire size and time since previous fire will influence future burn rates is poorly understood, mostly because of incomplete records of past fire overlaps. Here, we reconstruct the length of overlapping fires along a 190-km-long transect during the last 200 y in one of the most fire-prone boreal regions of North America to document how fire size and time since previous fire will influence future fire recurrence. We provide direct field evidence that extreme burn rates can be sustained by a few occasional droughts triggering immense fires. However, we also show that the most fire-prone areas of the North American boreal forest are resistant to high burn rates because of overabundant young forest stands, thereby creating a fuel-mediated negative feedback on fire activity. These findings will help refine projections of fire effect on boreal ecosystems and their large carbon stocks. PMID:25201981

  12. Resistance of the boreal forest to high burn rates.

    PubMed

    Héon, Jessie; Arseneault, Dominique; Parisien, Marc-André

    2014-09-23

    Boreal ecosystems and their large carbon stocks are strongly shaped by extensive wildfires. Coupling climate projections with records of area burned during the last 3 decades across the North American boreal zone suggests that area burned will increase by 30-500% by the end of the 21st century, with a cascading effect on ecosystem dynamics and on the boreal carbon balance. Fire size and the frequency of large-fire years are both expected to increase. However, how fire size and time since previous fire will influence future burn rates is poorly understood, mostly because of incomplete records of past fire overlaps. Here, we reconstruct the length of overlapping fires along a 190-km-long transect during the last 200 y in one of the most fire-prone boreal regions of North America to document how fire size and time since previous fire will influence future fire recurrence. We provide direct field evidence that extreme burn rates can be sustained by a few occasional droughts triggering immense fires. However, we also show that the most fire-prone areas of the North American boreal forest are resistant to high burn rates because of overabundant young forest stands, thereby creating a fuel-mediated negative feedback on fire activity. These findings will help refine projections of fire effect on boreal ecosystems and their large carbon stocks.

  13. A model for the burning rates of composite propellants

    NASA Technical Reports Server (NTRS)

    Cohen, N. S.; Strand, L. D.

    1980-01-01

    An analytical model of the steady-state burning of composite solid propellants is presented. An improved burning rate model is achieved by incorporating an improved AP monopropellant model, a separate energy balance for the binder in which a portion of the diffusion flame is used to heat the binder, proper use of the binder regression rate in the model, and a model for the combustion of the energetic binder component of CMDB propellants. Also, an improved correlation and model of aluminum agglomeration is developed which properly describes compositional trends.

  14. Rates of dysfunction in parents of pediatric patients with burns.

    PubMed

    Kendall-Grove; Ehde, D M; Patterson, D R; Johnson, V

    1998-01-01

    The purpose of the current study was to examine the rates of family and child dysfunction in a prospectively, consecutively admitted sample of children. One hundred eleven parents of children consecutively admitted for burn treatment were interviewed using a demographic questionnaire during their child's stay. Results of the questionnaire indicated that in 36% of the families, at least one parent reported significant dysfunction (history of substance abuse, involvement with Child Protective Services, incarceration, or psychiatric history). Results also indicated that 29% of the children over the age of 4 years had significant dysfunction (physical or sexual abuse, or both, psychiatric disorder, behavior problems, or learning disability. It was concluded that (1) parents of children with burns had a substantially high rate of dysfunction, (2) psychologic and preventive interventions should be focused on parents as well as children, and (3) burn injuries often should be regarded as a symptom rather than a cause of psychosocial problems in the family.

  15. Burning rate for steel-cased, pressed binderless HMX

    NASA Technical Reports Server (NTRS)

    Fifer, R. A.; Cole, J. E.

    1980-01-01

    The burning behavior of pressed binderless HMX laterally confined in 6.4 mm i.d. steel cases was measured over the pressure range 1.45 to 338 MPa in a constant pressure strand burner. The measured regression rates are compared to those reported previously for unconfined samples. It is shown that lateral confinement results in a several-fold decrease in the regression rate for the coarse particle size HMX above the transition to super fast regression. For class E samples, confinement shifts the transition to super fast regression from low pressure to high pressure. These results are interpreted in terms of the previously proposed progressive deconsolidation mechanism. Preliminary holographic photography and closed bomb tests are also described. Theoretical one dimensional modeling calculations were carried out to predict the expected flame height (particle burn out distance) as a function of particle size and pressure for binderless HMX burning by a progressive deconsolidation mechanism.

  16. Rill erosion rates in burned forests

    Treesearch

    Joseph W. Wagenbrenner; Peter R. Robichaud

    2011-01-01

    Introduction Wildfires often produce large increases in runoff and erosion rates (e.g., Moody and Martin, 2009), and land managers need to predict the frequency and magnitude of postfire erosion to determine the needs for hazard response and possible erosion mitigation to reduce the impacts of increased erosion on public safety and valued resources. The Water Erosion...

  17. The effect of wind on burning rate of wood cribs

    Treesearch

    Sara McAllister; Mark Finney

    2016-01-01

    Wood cribs are often used as ignition sources for room fire tests. A wood crib may also apply to studies of burning rate in wildland fires, because wildland fuel beds are porous and three dimensional. A unique aspect of wildland fires is the ubiquitous presence of wind. However, very little is known about what effect the increased ventilation has on the...

  18. OXIDATION OF MERCURY ACROSS SCR CATALYSTS IN COAL-FIRED POWER PLANTS BURNING LOW RANK FUELS

    SciTech Connect

    Constance Senior; Temi Linjewile

    2003-07-25

    This is the first Quarterly Technical Report for DOE Cooperative Agreement No: DE-FC26-03NT41728. The objective of this program is to measure the oxidation of mercury in flue gas across SCR catalyst in a coal-fired power plant burning low rank fuels using a slipstream reactor containing multiple commercial catalysts in parallel. The Electric Power Research Institute (EPRI) and Ceramics GmbH are providing co-funding for this program. This program contains multiple tasks and good progress is being made on all fronts. During this quarter, analysis of the coal, ash and mercury speciation data from the first test series was completed. Good agreement was shown between different methods of measuring mercury in the flue gas: Ontario Hydro, semi-continuous emission monitor (SCEM) and coal composition. There was a loss of total mercury across the commercial catalysts, but not across the blank monolith. The blank monolith showed no oxidation. The data from the first test series show the same trend in mercury oxidation as a function of space velocity that has been seen elsewhere. At space velocities in the range of 6,000-7,000 hr{sup -1} the blank monolith did not show any mercury oxidation, with or without ammonia present. Two of the commercial catalysts clearly showed an effect of ammonia. Two other commercial catalysts showed an effect of ammonia, although the error bars for the no-ammonia case are large. A test plan was written for the second test series and is being reviewed.

  19. Biomass burning fuel consumption rates: a field measurement database

    NASA Astrophysics Data System (ADS)

    van Leeuwen, T. T.; van der Werf, G. R.; Hoffmann, A. A.; Detmers, R. G.; Rücker, G.; French, N. H. F.; Archibald, S.; Carvalho, J. A., Jr.; Cook, G. D.; de Groot, W. J.; Hély, C.; Kasischke, E. S.; Kloster, S.; McCarty, J. L.; Pettinari, M. L.; Savadogo, P.; Alvarado, E. C.; Boschetti, L.; Manuri, S.; Meyer, C. P.; Siegert, F.; Trollope, L. A.; Trollope, W. S. W.

    2014-06-01

    Landscape fires show large variability in the amount of biomass or fuel consumed per unit area burned. These fuel consumption (FC) rates depend on the biomass available to burn and the fraction of the biomass that is actually combusted, and can be combined with estimates of area burned to assess emissions. While burned area can be detected from space and estimates are becoming more reliable due to improved algorithms and sensors, FC rates are either modeled or taken selectively from the literature. We compiled the peer-reviewed literature on FC rates for various biomes and fuel categories to better understand FC rates and variability, and to provide a~database that can be used to constrain biogeochemical models with fire modules. We compiled in total 76 studies covering 10 biomes including savanna (15 studies, average FC of 4.6 t DM (dry matter) ha-1), tropical forest (n = 19, FC = 126), temperate forest (n = 11, FC = 93), boreal forest (n = 16, FC = 39), pasture (n = 6, FC = 28), crop residue (n = 4, FC = 6.5), chaparral (n = 2, FC = 32), tropical peatland (n = 4, FC = 314), boreal peatland (n = 2, FC = 42), and tundra (n = 1, FC = 40). Within biomes the regional variability in the number of measurements was sometimes large, with e.g. only 3 measurement locations in boreal Russia and 35 sites in North America. Substantial regional differences were found within the defined biomes: for example FC rates of temperate pine forests in the USA were 38% higher than Australian forests dominated by eucalypt trees. Besides showing the differences between biomes, FC estimates were also grouped into different fuel classes. Our results highlight the large variability in FC rates, not only between biomes but also within biomes and fuel classes. This implies that care should be taken with using averaged values, and our comparison with FC rates from GFED3 indicates that also modeling studies have difficulty in representing the dynamics governing FC.

  20. Solid Propellant Burn Rate Modifiers Based on Reactive Nanocomposite Materials

    DTIC Science & Technology

    2010-10-26

    Burn Rate Modifiers Based on Reactive Nanocomposite Powders. Propellants Explosives and Pyrotechnics , 35, pp. 260 – 267 (2010) 8. Badiola, C...of Structural Refinement and Composition in Al-MoO3 Nanocomposites Prepared by Arrested Reactive Milling. Propellants Explosives and Pyrotechnics , 31...Reactive Nanocomposite Materials Prepared by Arrested Reactive Milling 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) E.L. Dreizin

  1. Theoretical Study on Nano-Catalyst Burn Rate

    DTIC Science & Technology

    2014-11-26

    perchlorate adsorption on surfaces and clusters. Both TiO2 surfaces of rutile and anatase phases were constructed and their energetic and thermodynamic...stability to understand electronic properties and reactivity of the most stable surface structures. Interaction of ammonium perchlorate (AP) with the... perchlorate adsorption on surfaces and clusters. Both TiO2 surfaces of rutile and anatase phases were constructed and their energetic and thermodynamic

  2. Leading Edge Flame Detachment: Effect on Burning Rate of Ammonium Perchlorate Propellants

    NASA Technical Reports Server (NTRS)

    Price, E. W.; Chakravarthy, S. R.; Sambamurthi, J. K.; Sigman, R. K.

    1997-01-01

    Inner details of the transition from premixed to diffusion controlled burning are examined by considering the transition at the individual particle flamelet level. These considerations lead to prediction of observable singular burning rate behavior of bimodal AP formulations. Burning rate measurements verify the predictions, supporting the view that particle flamelets become detached and retreat to more remote premixed locations at definite (particles size dependent) pressures, revealed by the burning rate tests.

  3. Traveling Charge Gun Firings Using Very High Burning Rate Propellants

    DTIC Science & Technology

    1988-12-01

    21.5 grams. This gave a charge-to-mass ratio of approximately 1.6. Data acquisition is done on analog tape, which is later digitized and reduced by...fashion. Pressure historias indica e a decreasing mass generation rate as a function of burn time. As a consequence of these two observations and in order...Station, Indian Head, MD, December 1980. 11. Gough, P.S., "Extensions of BRLTC. A Code for the Digital Simulation of the Traveling Charge," Contract Report

  4. Burns

    MedlinePlus

    ... clothing, except clothing imbedded in the burn. Run cool - not cold - water over the burn or hold ... chemicals should be flushed off affected areas with cool running water for 20 minutes or longer or ...

  5. Burns

    MedlinePlus

    ... occur by direct or indirect contact with heat, electric current, radiation, or chemical agents. Burns can lead to ... is. The burn is caused by chemicals or electricity. The person shows signs of shock . The person ...

  6. Degree of rate control approach to computational catalyst screening

    SciTech Connect

    Wolcott, Christopher A.; Medford, Andrew J.; Studt, Felix; Campbell, Charles T.

    2015-10-01

    A new method for computational catalyst screening that is based on the concept of the degree of rate control (DRC) is introduced. It starts by developing a full mechanism and microkinetic model at the conditions of interest for a reference catalyst (ideally, the best known material) and then determines the degrees of rate control of the species in the mechanism (i.e., all adsorbed intermediates and transition states). It then uses the energies of the few species with the highest DRCs for this reference catalyst as descriptors to estimate the rates on related materials and predict which are most active. The predictions of this method regarding the relative rates of twelve late transition metals for methane steam reforming, using the Rh(2 1 1) surface as the reference catalyst, are compared to the most commonly-used approach for computation catalyst screening, the Nørskov–Bligaard (NB) method which uses linear scaling relationships to estimate the energies of all adsorbed intermediates and transition states. It is slightly more accurate than the NB approach when the metals are similar to the reference metal (<0.5 eV different on a plot where the axes are the bond energies to C and O adatoms), but worse when too different from the reference. It is computationally faster than the NB method when screening a moderate number of materials (<100), thus adding a valuable complement to the NB approach. It can be implemented without a microkinetic model if the degrees of rate control are already known approximately, e.g., from experiments.

  7. Criteria pollutant and greenhouse gas emissions from CNG transit buses equipped with three-way catalysts compared to lean-burn engines and oxidation catalyst technologies.

    PubMed

    Yoon, Seungju; Collins, John; Thiruvengadam, Arvind; Gautam, Mridul; Herner, Jorn; Ayala, Alberto

    2013-08-01

    Engine and exhaust control technologies applied to compressed natural gas (CNG) transit buses have advanced from lean-burn, to lean-burn with oxidation catalyst (OxC), to stoichiometric combustion with three-way catalyst (TWC). With this technology advancement, regulated gaseous and particulate matter emissions have been significantly reduced. Two CNG transit buses equipped with stoichiometric combustion engines and TWCs were tested on a chassis dynamometer, and their emissions were measured. Emissions from the stoichiometric engines with TWCs were then compared to the emissions from lean-burn CNG transit buses tested in previous studies. Stoichiometric combustion with TWC was effective in reducing emissions of oxides of nitrogen (NO(x)), particulate matter (PM), and nonmethane hydrocarbon (NMHC) by 87% to 98% depending on pollutants and test cycles, compared to lean combustion. The high removal efficiencies exceeded the emission reduction required from the certification standards, especially for NO(x) and PM. While the certification standards require 95% and 90% reductions for NO(x) and PM, respectively, from the engine model years 1998-2003 to the engine model year 2007, the measured NO(x) and PM emissions show 96% and 95% reductions, respectively, from the lean-burn engines to the stoichiometric engines with TWC over the transient Urban Dynamometer Driving Schedule (UDDS) cycle. One drawback of stoichiometric combustion with TWC is that this technology produces higher carbon monoxide (CO) emissions than lean combustion. In regard to controlling CO emissions, lean combustion with OxC is more effective than stoichiometric combustion. Stoichiometric combustion with TWC produced higher greenhouse gas (GHG) emissions including carbon dioxide (CO2) and methane (CH4) than lean combustion during the UDDS cycle, but lower GHG emissions during the steady-state cruise cycle. Stoichiometric combustion with three-way catalyst is currently the best emission control technology

  8. Flame surface density and burning rate in premixed turbulent flames

    SciTech Connect

    Shepherd, I.G.

    1995-10-01

    The flame surface density has been measured in hydrocarbon/air stagnation point and v-shaped premixed turbulent flames. A method is proposed to determine the flame surface density from the data obtained by laser sheet tomography. The average flame length and flame zone area as a function of the progress variable are calculated from a map of progress variable and a set of flame edges obtained from the tomographs. From these results a surface density estimate in two dimensions is determined. By this technique it is possible to avoid the difficulties which arise when using an algebraic model based on the measurement of the flame front geometry and a scalar length scale. From these results the burning rate can be obtained which compares well with estimates calculated using the fractal technique. The present method, however, is not constrained by a minimum window size as is the case for the fractal determinations.

  9. Effect of pressure on rate of burning /decomposition with flame/ of liquid hydrazine.

    NASA Technical Reports Server (NTRS)

    Antoine, A. C.

    1966-01-01

    Liquid hydrazine decomposition process to determine what chemical or physical changes may be occurring that cause breaks in burning rate/ pressure curves, measuring flame temperature and light emission

  10. Chemical and toxicological properties of emissions from CNG transit buses equipped with three-way catalysts compared to lean-burn engines and oxidation catalyst technologies

    NASA Astrophysics Data System (ADS)

    Yoon, Seungju; Hu, Shaohua; Kado, Norman Y.; Thiruvengadam, Arvind; Collins, John F.; Gautam, Mridul; Herner, Jorn D.; Ayala, Alberto

    2014-02-01

    Chemical and toxicological properties of emissions from compressed natural gas (CNG) fueled transit buses with stoichiometric combustion engines and three-way catalyst (TWC) exhaust control systems were measured using a chassis dynamometer testing facility and compared to the data from earlier CNG engine and exhaust control technologies. Gaseous and particulate matter emissions from buses with stoichiometric engines and TWC were significantly lower than the emissions from buses with lean-burn engines. Carbonyls and volatile organic compounds (VOCs) from buses with stoichiometric engines and TWC were lower by more than 99% compared to buses with lean-burn engines. Elemental and organic carbons (EC and OC), polycyclic aromatic hydrocarbons (PAHs), and trace elements from buses with stoichiometric engines and TWC were effectively controlled and significantly lower than the emissions from buses with lean-burn engines. Potential mutagenicity measured using a microsuspension modification of the Salmonella/microsome assay was lower by more than 99% for buses with stoichiometric engines and TWC, compared to buses with lean-burn engines and OxC.

  11. Analysis of the burns profile and the admission rate of severely burned adult patient to the National Burn Center of Chile after the 2010 earthquake.

    PubMed

    Albornoz, Claudia; Villegas, Jorge; Sylvester, Marilu; Peña, Veronica; Bravo, Iside

    2011-06-01

    Chile is located in the Ring of Fire, in South America. An earthquake 8.8° affected 80% of the population in February 27th, 2010. This study was conducted to assess any change in burns profile caused by the earthquake. This was an ecologic study. We compared the 4 months following the earthquake in 2009 and 2010. age, TBSA, deep TBSA, agent, specific mortality rate and rate of admissions to the National burn Center of Chile. Mann-Whitney test and a Poisson regression were performed. Age, agent, TBSA and deep TBSA percentages did not show any difference. Mortality rate was lower in 2010 (0.52 versus 1.22 per 1,000,000 habitants) but no meaningful difference was found (Poisson regression p = 0.06). Admission rate was lower in 2010, 4.6 versus 5.6 per 1,000,000 habitants, but no differences were found (p = 0.26). There was not any admissions directly related to the earthquake. As we do not have incidence registries in Chile, we propose to use the rate of admission to the National Burn Reference Center as an incidence estimator. There was not any significant difference in the burn profile, probably because of the time of the earthquake (3 am). We conclude the earthquake did not affect the way the Chilean people get burned. Copyright © 2011 Elsevier Ltd and ISBI. All rights reserved.

  12. Turbulent burning rates of methane and methane-hydrogen mixtures

    SciTech Connect

    Fairweather, M.; Ormsby, M.P.; Sheppard, C.G.W.; Woolley, R.

    2009-04-15

    Methane and methane-hydrogen (10%, 20% and 50% hydrogen by volume) mixtures have been ignited in a fan stirred bomb in turbulence and filmed using high speed cine schlieren imaging. Measurements were performed at 0.1 MPa (absolute) and 360 K. A turbulent burning velocity was determined for a range of turbulence velocities and equivalence ratios. Experimental laminar burning velocities and Markstein numbers were also derived. For all fuels the turbulent burning velocity increased with turbulence velocity. The addition of hydrogen generally resulted in increased turbulent and laminar burning velocity and decreased Markstein number. Those flames that were less sensitive to stretch (lower Markstein number) burned faster under turbulent conditions, especially as the turbulence levels were increased, compared to stretch-sensitive (high Markstein number) flames. (author)

  13. Burns

    MedlinePlus

    ... cause swelling, blistering, scarring and, in serious cases, shock, and even death. They also can lead to infections because they damage your skin's protective barrier. Treatment for burns depends on the cause of the ...

  14. The burning rate of energetic films of nanostructured porous silicon.

    PubMed

    Plummer, Andrew; Kuznetsov, Valerian; Joyner, Timothy; Shapter, Joe; Voelcker, Nicolas H

    2011-12-02

    A systematic study of nanoenergetic films consisting of nanostructured porous silicon impregnated with sodium perchlorate is carried out. The explosive properties of these films are investigated as a function of thickness, porosity, and confinement. The films' burning rates are investigated using fiber-optic velocity probes, demonstrating that flame-front velocities vary between approximately 1 and 500 m s(-1) and are very sensitive to the films' structural characteristics. Analysis of the flame profile by high-speed video is also presented, suggesting that the reaction type is a deflagration rather than a detonation. A strong plume of flame is emitted from the surface, indicating the potential for this material to perform useful work either as an initiator or as a propellant. The shape of the flame front transitioned from an inverted V at thin-film thicknesses to a neat square-shaped front once the material became self-confining at 50 μm. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Epidemiological data and mortality rate of patients hospitalized with burns in Brazil.

    PubMed

    De-Souza, D A; Marchesan, W G; Greene, L J

    1998-08-01

    This retrospective analysis of burn patients in a University Hospital in the state of São Paulo, Brazil, was carried out to characterize this population and to identify the factors that affect the mortality rate. All patients hospitalized from January 1990 to April 1995 (n = 229, 3.6 patients/month) and who terminated treatment were included. Of these, 80.8% (185 patients) were hospitalized within 24 h of the burn. Occupational and/or domestic accidents were responsible for most of the burns (78.6%), which were mainly caused by a direct flame (71.2%). with alcohol being the flammable fluid most frequently used. The average patient treated at the center was a male of 9 years of age or less with 20-40% burned body surface, who received care within 24 h after suffering an accidental alcohol burn and who was hospitalized for < or =30 days. The mortality rate was 18.8% for all patients and increased with burned body surface and age, and for suicide patients. Suicide attempts for all patients > or = 18 years were the cause of 46 .5% (20/43) of the burns involving women and of 8.9% (8/90) of the burns involving men. The mortality rate was significantly higher for self-inflicted burns (42.9%) than for accidental burns (20.2%).

  16. BURNING RATES OF SOLID COMPOSITE PROPELLANTS AT PRESSURES UP TO 20,000 PSIG

    DTIC Science & Technology

    Strand burning rates of ammonium perchlorate-containing composite propellants having plastisol -nitrocellulose, carboxyl-terminated-polybutadiene, and...little effect on the pressure-dependence of the burning rate at high pressure. The pressure exponents of plastisol -nitrocellulose formulations reach

  17. Results of Propellant Mixing Variable Study Using Precise Pressure-Based Burn Rate Calculations

    NASA Technical Reports Server (NTRS)

    Stefanski, Philip L.

    2014-01-01

    A designed experiment was conducted in which three mix processing variables (pre-curative addition mix temperature, pre-curative addition mixing time, and mixer speed) were varied to estimate their effects on within-mix propellant burn rate variability. The chosen discriminator for the experiment was the 2-inch diameter by 4-inch long (2x4) Center-Perforated (CP) ballistic evaluation motor. Motor nozzle throat diameters were sized to produce a common targeted chamber pressure. Initial data analysis did not show a statistically significant effect. Because propellant burn rate must be directly related to chamber pressure, a method was developed that showed statistically significant effects on chamber pressure (either maximum or average) by adjustments to the process settings. Burn rates were calculated from chamber pressures and these were then normalized to a common pressure for comparative purposes. The pressure-based method of burn rate determination showed significant reduction in error when compared to results obtained from the Brooks' modification of the propellant web-bisector burn rate determination method. Analysis of effects using burn rates calculated by the pressure-based method showed a significant correlation of within-mix burn rate dispersion to mixing duration and the quadratic of mixing duration. The findings were confirmed in a series of mixes that examined the effects of mixing time on burn rate variation, which yielded the same results.

  18. Combustion Studies of Very High Burning Rate (VHBR) Propellants

    DTIC Science & Technology

    1982-02-01

    configuration involved the use of a cigarette type or end burning propellant grain. The charge would be made of parallel layers of successively higher... DDT ) characterization. (See references 13, 14, and 15 for details). 12 I. W. May, A. F. Bavan, P. G. Baev, and P. S. Gough, "The...All samples were end ignited to burn cigarette fashion, although in the case of the bare 12.7-mm sample firings no inhibitor was used on the sides

  19. Enhancement in Rate of Photocatalysis Upon Catalyst Recycling

    NASA Astrophysics Data System (ADS)

    Sorathiya, Kalpesh; Mishra, Biswajit; Kalarikkal, Abhishek; Reddy, Kasala Prabhakar; Gopinath, Chinnakonda S.; Khushalani, Deepa

    2016-10-01

    Recyclability is an important aspect for heterogeneous photo-catalysts. Ease of recovery and stability of the photo-catalyst in terms of efficiency over the number of cycles are highly desired and in fact it is ideal if the efficiency is constant and it should not decrease marginally with each cycle. Presented here is a seminal observation in which the photocatalytic activity is shown to improve with increasing number of catalytic cycles (it is 1.7 times better after the 1st cycle and 3.1 times better after the 2nd cycle). Specifically, nanorods of pure TiO2 and TiO2 doped with controlled amount of tungsten have been used to degrade two model pollutants: Phenol and Rhodamine B under exclusive visible light illumination. It was found that, in case of 1 mol.% W incorporation, rate of photocatalysis and also the range of visible light absorption of the photocatalyst increased after the photocatalysis as compared to before photocatalysis. This aspect is unique for doped TiO2 and hence provides an intriguing way to mitigate low photoactivity.

  20. Enhancement in Rate of Photocatalysis Upon Catalyst Recycling

    PubMed Central

    Sorathiya, Kalpesh; Mishra, Biswajit; Kalarikkal, Abhishek; Reddy, Kasala Prabhakar; Gopinath, Chinnakonda S.; Khushalani, Deepa

    2016-01-01

    Recyclability is an important aspect for heterogeneous photo-catalysts. Ease of recovery and stability of the photo-catalyst in terms of efficiency over the number of cycles are highly desired and in fact it is ideal if the efficiency is constant and it should not decrease marginally with each cycle. Presented here is a seminal observation in which the photocatalytic activity is shown to improve with increasing number of catalytic cycles (it is 1.7 times better after the 1st cycle and 3.1 times better after the 2nd cycle). Specifically, nanorods of pure TiO2 and TiO2 doped with controlled amount of tungsten have been used to degrade two model pollutants: Phenol and Rhodamine B under exclusive visible light illumination. It was found that, in case of 1 mol.% W incorporation, rate of photocatalysis and also the range of visible light absorption of the photocatalyst increased after the photocatalysis as compared to before photocatalysis. This aspect is unique for doped TiO2 and hence provides an intriguing way to mitigate low photoactivity. PMID:27731347

  1. Enhancement in Rate of Photocatalysis Upon Catalyst Recycling.

    PubMed

    Sorathiya, Kalpesh; Mishra, Biswajit; Kalarikkal, Abhishek; Reddy, Kasala Prabhakar; Gopinath, Chinnakonda S; Khushalani, Deepa

    2016-10-12

    Recyclability is an important aspect for heterogeneous photo-catalysts. Ease of recovery and stability of the photo-catalyst in terms of efficiency over the number of cycles are highly desired and in fact it is ideal if the efficiency is constant and it should not decrease marginally with each cycle. Presented here is a seminal observation in which the photocatalytic activity is shown to improve with increasing number of catalytic cycles (it is 1.7 times better after the 1(st) cycle and 3.1 times better after the 2(nd) cycle). Specifically, nanorods of pure TiO2 and TiO2 doped with controlled amount of tungsten have been used to degrade two model pollutants: Phenol and Rhodamine B under exclusive visible light illumination. It was found that, in case of 1 mol.% W incorporation, rate of photocatalysis and also the range of visible light absorption of the photocatalyst increased after the photocatalysis as compared to before photocatalysis. This aspect is unique for doped TiO2 and hence provides an intriguing way to mitigate low photoactivity.

  2. Burn rates of pristine and degraded explosives at elevated temperatures and pressures

    SciTech Connect

    Chandler, J B; Maienschein, J L

    1998-08-10

    We measure the Laminar burn rates of explosives at extreme conditions (up to 520K and 1 GPa) in a hybrid strand burner, to provide reaction rate data for prediction of violence of thermal response. Data from a series of HMX-based explosives show that explosives with high binder content (15 wt%) burn smoothly over the entire pressure range regardless of particle size, while explosives with less binder eventually transition to a rapid erratic burn 10-100 times faster. When heated to ~ 440K, an HMX formulation with fine particles and 15% binder exhibits different burning behav- ior depending on the details of the temperature-pressure history, apparently as a result of the {beta} {yields} {delta} phase transition in HMX. Burn rates can be increased by 1000-fold under certain conditions.

  3. Burning rate of merged pool fire on the hollow square tray.

    PubMed

    Wang, Changjian; Guo, Jin; Ding, Yanming; Wen, Jennifer; Lu, Shouxiang

    2015-06-15

    In order to characterize fire merging, pool fires on hollow trays with varying side lengths were burned under quasi-quiescent condition and in a wind tunnel with the wind speed ranging from 0m/s to 7.5m/s. Burning rate and flame images were recorded in the whole combustion process. The results show that even though the pool surface area was kept identical for hollow trays of different sizes, the measured burning rates and fire evolutions were found to be significantly different. Besides the five stages identified by previous studies, an extra stage, fire merging, was observed. Fire merging appeared possibly at any of the first four stages and moreover resulted in 50-100% increases of the fire burning rates and heights in the present tests. The tests in wind tunnel suggested that, as the wind speed ranges from 0 m/s to 2 m/s, the burning rates decrease. However with further increase of the wind speed from 2 m/s to 7.5 m/s, the burning rate was found to increase for smaller hollow trays while it remains almost constant for larger hollow trays. Two empirical correlations are presented to predict critical burning rate of fire merging on the hollow tray. The predictions were found to be in reasonably good agreement with the measurements. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. A miniscale ballistic test motor for propellant burning rate characterization from one motor firing

    NASA Astrophysics Data System (ADS)

    Rast, Robert H.; Boyles, Sharon M.; Obney, Phyllis

    1992-07-01

    A mini ballistic test motor for burn rate characterization from one motor firing has been developed. The small charge weight required for this motor allows ballistic characterization of small scale lot set evaluation and R&D propellant mixes in a rocket motor environment. This paper presents results comparing the mini-motor to the standard Naval Surface Warfare Center, Indian Head (IHDIVNAVSURFWARCEN) ballistic test motor, (BTM). Burn rate data from the standard BTM and mini BTM show excellent agreement.

  5. Deuterium Isotope Effects During HMX Combustion: Chemical Kinetic Burn Rate Control Mechanism Verified

    DTIC Science & Technology

    1989-01-01

    propellant contain- controls the I-IMX burn rate in the pressure range cited. The ing a chemically modified double base ( CMDB ) high oxygen 1.41 KDIE...controlling the observed overall or global burn rate of the could expect from the deuterium labeled HMX methylene HMX/ CMDB composite propellant. It is...measured in the HMX/ CMDB system. A graphic representa- densed phase KDIE investigation of thermochemical decom- non of one cornposic HMX binder

  6. Strand Burn Rates of Black Powder to One Hundred Atmospheres

    DTIC Science & Technology

    1983-05-01

    Mechanism of SUper-Pate Burning of CataZtaed Double Base PropeZlant.," Report No. AMS 1087, Dept. of Aerospace and Mechanical Sciences, Pinceton University...so often reported as affecting response, is proportional to its density. This author is guided by A. Kirshenbaum’s 7K. White and R. &azeee...Development laboratory ATTN: ATSH-CD-CSO-OR Ames Research Center Fort Benning, GA 31905 Moffett Field , CA 94035 J 29 - DISTRXBITITO1l LIST No. Of No. Of

  7. Biomass burning fuel consumption rates: a field measurement database

    NASA Astrophysics Data System (ADS)

    van Leeuwen, T. T.; van der Werf, G. R.; Hoffmann, A. A.; Detmers, R. G.; Rücker, G.; French, N. H. F.; Archibald, S.; Carvalho, J. A., Jr.; Cook, G. D.; de Groot, W. J.; Hély, C.; Kasischke, E. S.; Kloster, S.; McCarty, J. L.; Pettinari, M. L.; Savadogo, P.; Alvarado, E. C.; Boschetti, L.; Manuri, S.; Meyer, C. P.; Siegert, F.; Trollope, L. A.; Trollope, W. S. W.

    2014-12-01

    Landscape fires show large variability in the amount of biomass or fuel consumed per unit area burned. Fuel consumption (FC) depends on the biomass available to burn and the fraction of the biomass that is actually combusted, and can be combined with estimates of area burned to assess emissions. While burned area can be detected from space and estimates are becoming more reliable due to improved algorithms and sensors, FC is usually modeled or taken selectively from the literature. We compiled the peer-reviewed literature on FC for various biomes and fuel categories to understand FC and its variability better, and to provide a database that can be used to constrain biogeochemical models with fire modules. We compiled in total 77 studies covering 11 biomes including savanna (15 studies, average FC of 4.6 t DM (dry matter) ha-1 with a standard deviation of 2.2), tropical forest (n = 19, FC = 126 ± 77), temperate forest (n = 12, FC = 58 ± 72), boreal forest (n = 16, FC = 35 ± 24), pasture (n = 4, FC = 28 ± 9.3), shifting cultivation (n = 2, FC = 23, with a range of 4.0-43), crop residue (n = 4, FC = 6.5 ± 9.0), chaparral (n = 3, FC = 27 ± 19), tropical peatland (n = 4, FC = 314 ± 196), boreal peatland (n = 2, FC = 42 [42-43]), and tundra (n = 1, FC = 40). Within biomes the regional variability in the number of measurements was sometimes large, with e.g. only three measurement locations in boreal Russia and 35 sites in North America. Substantial regional differences in FC were found within the defined biomes: for example, FC of temperate pine forests in the USA was 37% lower than Australian forests dominated by eucalypt trees. Besides showing the differences between biomes, FC estimates were also grouped into different fuel classes. Our results highlight the large variability in FC, not only between biomes but also within biomes and fuel classes. This implies that substantial uncertainties are associated with using biome-averaged values to represent FC for whole

  8. Addendum to High Pressure Burn Rate Measurements on an Ammonium Perchlorate Propellant

    SciTech Connect

    Glascoe, E A; Tan, N

    2010-11-08

    As part of a small follow-on study, the burn rate of the ammonium perchlorate (AP) based material TAL-1503 was studied at a relatively mild pressure. The goal of this final experiment was to burn TAL-1503 at the lowest pressures possible using the LLNL High Pressure Strand Burner (LLNL-HPSB). The following is a description of the experiment and the results with a brief discussion of data and a comparison to the higher pressure data. This is not meant to be a stand-alone report and readers should refer to the main report for experimental details and discussion. High pressure deflagration rate measurements of a unique AP/HTPB based material (TAL-1503) were performed using the LLNL high pressure strand burner apparatus. The material burns in a well behaved, laminar fashion between 20 and 300 MPa with a burn law of B = (0.6 {+-} 0.1) x P{sup (1.05{+-}0.02)} that was calculated based on the best data available from the experiments. In the pressure range of 2 and 10 MPa the material burned laminarly with a burn law of B = (2.0 {+-} 0.2) x P{sup (0.66{+-}0.05)}. In these results, B is the burn rate in mm/s and P is the pressure in units of MPa. Comparison of the TAL-1503 results with similar propellants that contain micrometer sized aluminum indicate that the burn rates are relatively unaffected by the aluminum. However, the pressure change is significantly larger when aluminum is present, most likely due to the high temperatures achieved from burning aluminum.

  9. Prospective analysis of nosocomial infection rates, antibiotic use, and patterns of resistance in a burn population.

    PubMed

    Wibbenmeyer, Lucy; Danks, Roy; Faucher, Lee; Amelon, Marge; Latenser, Barbara; Kealey, G Patrick; Herwaldt, Loreen A

    2006-01-01

    Despite significant advances in burn care, infection remains a major cause of morbidity and mortality in burn patients. We sought to determine accurate infection rates, risk factors for infection, and the percentage of infections caused by resistant organisms. In addition, we attempted to identify interventions to decrease the use of antimicrobial drugs. Data were collected prospectively from 157 burn patients admitted to the University of Iowa Carver College of Medicine burn treatment center from October 2001 to October 2002. A research assistant reviewed the medical record for each patient identified by burn surgeons as being infected to determine whether these episodes met the infection control criteria for nosocomial infections. The infection control assessment agreed with the surgeon's assessment for 16.7% of the pneumonias, 70.0% of the burn wound infections, 57.1% of the urinary tract infections, and 70.0% of the bloodstream infections. By multiple logistic regression analysis, body surface area burned, comorbidities, and use of invasive devices were significantly related to acquisition of nosocomial infections as identified by both the burn surgeons and the infection control criteria. Staphylococcus aureus and Pseudomonas were the most common resistant organisms identified. In our population, surgeons could decrease antimicrobial use by using explicit criteria for identifying patients with hospital-acquired infections, limiting perioperative prophylaxis to patients at highest risk of infection, and decreasing the incidence of nosocomial infection with reduced use of devices and strict adherence to aseptic technique.

  10. Growth rate predicts mortality of Abies concolor in both burned and unburned stands

    USGS Publications Warehouse

    van Mantgem, Phillip J.; Stephenson, Nathan L.; Mutch, Linda S.; Johnson, Veronica G.; Esperanza, Annie M.; Parsons, David J.

    2003-01-01

    Tree mortality is often the result of both long-term and short-term stress. Growth rate, an indicator of long-term stress, is often used to estimate probability of death in unburned stands. In contrast, probability of death in burned stands is modeled as a function of short-term disturbance severity. We sought to narrow this conceptual gap by determining (i) whether growth rate, in addition to crown scorch, is a predictor of mortality in burned stands and (ii) whether a single, simple model could predict tree death in both burned and unburned stands. Observations of 2622 unburned and 688 burned Abies concolor (Gord. & Glend.) Lindl. (white fir) in the Sierra Nevada of California, U.S.A., indicated that growth rate was a significant predictor of mortality in the unburned stands, while both crown scorch and radial growth were significant predictors of mortality in the burned stands. Applying the burned stand model to unburned stands resulted in an overestimation of the unburned stand mortality rate. While failing to create a general model of tree death for A. concolor, our findings underscore the idea that similar processes may affect mortality in disturbed and undisturbed stands.

  11. Reaction rate and composition dependence of the stability of thermonuclear burning on accreting neutron stars

    SciTech Connect

    Keek, L.; Cyburt, R. H.; Heger, A.

    2014-06-01

    The stability of thermonuclear burning of hydrogen and helium accreted onto neutron stars is strongly dependent on the mass accretion rate. The burning behavior is observed to change from Type I X-ray bursts to stable burning, with oscillatory burning occurring at the transition. Simulations predict the transition at a 10 times higher mass accretion rate than observed. Using numerical models we investigate how the transition depends on the hydrogen, helium, and CNO mass fractions of the accreted material, as well as on the nuclear reaction rates of 3α and the hot-CNO breakout reactions {sup 15}O(α, γ){sup 19}Ne and {sup 18}Ne(α, p){sup 21}Na. For a lower hydrogen content the transition is at higher accretion rates. Furthermore, most experimentally allowed reaction rate variations change the transition accretion rate by at most 10%. A factor 10 decrease of the {sup 15}O(α, γ){sup 19}Ne rate, however, produces an increase of the transition accretion rate of 35%. None of our models reproduce the transition at the observed rate, and depending on the true {sup 15}O(α, γ){sup 19}Ne reaction rate, the actual discrepancy may be substantially larger. We find that the width of the interval of accretion rates with marginally stable burning depends strongly on both composition and reaction rates. Furthermore, close to the stability transition, our models predict that X-ray bursts have extended tails where freshly accreted fuel prolongs nuclear burning.

  12. Solid Propellant Subscale Burning Rate Analysis Methods for US and Selected NATO Facilities

    DTIC Science & Technology

    2002-01-01

    geometry) and their evolution in time. Internal ballistics is the applied science devoted to these problems. 4 Burning Rat In general, burning rates depend...Lecture Series, 36 th Aerospace Sciences Meeting, January 1998. 4 Fry, R.S., -Solid Propellant Test Motor Scaling," JHU/CPIA CPTR 73, September 2001...PhD Thesis, Aerospace and Mechanical Sciences Department. 21 A. Davenas et Collaborateurs, Technologie des Propergols Solides. Masson, Paris, France

  13. Effective helium burning rates and the production of the neutrino nuclei.

    PubMed

    Austin, Sam M; West, Christopher; Heger, Alexander

    2014-03-21

    Effective values for the key helium burning reaction rates, triple-α and (12)C(α, γ)(16)O, are obtained by adjusting their strengths so as to obtain the best match with the solar abundance pattern of isotopes uniquely or predominately made in core-collapse supernovae. These effective rates are then used to determine the production of the neutrino isotopes. The use of effective rates considerably reduces the uncertainties in the production factors arising from uncertainties in the helium burning rates, and improves our ability to use the production of B11 to constrain the neutrino emission from supernovae.

  14. Origins of initiation rate differences in ruthenium olefin metathesis catalysts containing chelating benzylidenes.

    PubMed

    Engle, Keary M; Lu, Gang; Luo, Shao-Xiong; Henling, Lawrence M; Takase, Michael K; Liu, Peng; Houk, K N; Grubbs, Robert H

    2015-05-06

    A series of second-generation ruthenium olefin metathesis catalysts was investigated using a combination of reaction kinetics, X-ray crystallography, NMR spectroscopy, and DFT calculations in order to determine the relationship between the structure of the chelating o-alkoxybenzylidene and the observed initiation rate. Included in this series were previously reported catalysts containing a variety of benzylidene modifications as well as four new catalysts containing cyclopropoxy, neopentyloxy, 1-adamantyloxy, and 2-adamantyloxy groups. The initiation rates of this series of catalysts were determined using a UV/vis assay. All four new catalysts were observed to be faster-initiating than the corresponding isopropoxy control, and the 2-adamantyloxy catalyst was found to be among the fastest-initiating Hoveyda-type catalysts reported to date. Analysis of the X-ray crystal structures and computed energy-minimized structures of these catalysts revealed no correlation between the Ru-O bond length and Ru-O bond strength. On the other hand, the initiation rate was found to correlate strongly with the computed Ru-O bond strength. This latter finding enables both the rationalization and prediction of catalyst initiation through the calculation of a single thermodynamic parameter in which no assumptions about the mechanism of the initiation step are made.

  15. The correlation between burn mortality rates from fire and flame and economic status of countries.

    PubMed

    Peck, Michael; Pressman, Melissa A

    2013-09-01

    Over 95% of burn deaths occur in low- and middle-income countries globally. However, the association between burn mortality rates and economic health has not been evaluated for individual countries. This study seeks to answer the question, how strong is the correlation between burn mortality and national indices of economic strength? A retrospective review was performed for 189 countries during 2008-2010 using economic data from the World Bank as well as mortality data from the World Health Organization (WHO). Countries were categorized into four groups based on income level according to stratification by the World Bank: low income, lower middle income, upper middle income, and high income. The Pearson correlation coefficient was used to estimate presence and strength of association among death rates, Gini coefficient (measure of inequality of distribution of wealth), gross domestic product (GDP) per capita, and gross national index (GNI) per capita. Statistically significant associations (p<0.05) were found between burn mortality and GDP per capita (r=-0.26), GNI per capita (r=-0.36), and Gini (r=+0.17). A nation's income level is negatively correlated with burn mortality; the lower the income level, the higher the burn mortality rates. The degree to which income within a country is equitably or inequitably distributed also correlates with burn mortality. Both governmental and non-governmental organizations need to focus on preventing burns in low-income countries, as well as in other countries in which there is marked disparity of income. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.

  16. System and method for determining an ammonia generation rate in a three-way catalyst

    DOEpatents

    Sun, Min; Perry, Kevin L; Kim, Chang H

    2014-12-30

    A system according to the principles of the present disclosure includes a rate determination module, a storage level determination module, and an air/fuel ratio control module. The rate determination module determines an ammonia generation rate in a three-way catalyst based on a reaction efficiency and a reactant level. The storage level determination module determines an ammonia storage level in a selective catalytic reduction (SCR) catalyst positioned downstream from the three-way catalyst based on the ammonia generation rate. The air/fuel ratio control module controls an air/fuel ratio of an engine based on the ammonia storage level.

  17. [Alumina-supported catalysts for the catalytic purification of lean-burn automobile exhaust].

    PubMed

    Zhu, Tian-le; Hao, Ji-ming; Fu, Li-xin; Wang, Jian-xin; Li, Jun-hua; Liu, Zhi-ming; Cui, Xiang-yu

    2004-05-01

    Catalytic properties of Ag/Al2O3, In/Al2O3, Sn/Al2O3, Co/Al2O3, Pt/Al2O3 and a two-stage catalyst composed of Ag/Al2O3 and Pt/Al2O3 were investigated for the selective reduction of NO by C3H6 or C2H5OH in excess oxygen. The Ag/Al2O3 showed the highest NO reduction activity among the catalysts studied. A substantial amount of CO was formed over alumina-based transient metal oxides. HC and CO oxidations over Pt/Al2O3 occurred in relatively low temperatures, compared with the other catalysts. The sequential use of Ag/Al2O3 and Pt/Al2O3 was effective to broaden the temperature window for the reduction of NO, to improve oxidation of HC and CO and to inhibit the formation of N2O and CH3CHO.

  18. Burning Rates of Standard Army Propellants in Strand Burner and Closed Chamber Tests

    DTIC Science & Technology

    1977-08-01

    National Technical Information Service, U.S. Department of Commerce, Springfield, Virginia 22151. "I !I ea 4 I I.( I I The findings in this report are...once initiated, goes forward rapidly--in common parlance, the powder burns." The National Defense Research Committee published in 1946 a summary of their...8217o~ N 4; u4 - as Ncc .. .00 0. CA WN w N. CLgoa N12N. Table II. Burning Rate Results for BRL Extruded Standard Propellants (Rates in./s) Prope I lant

  19. Plasma physics effects on thermonuclear burn rate in the presence of hydrodynamic mix

    NASA Astrophysics Data System (ADS)

    Tang, Xian-Zhu; Guo, Zehua; Kagan, Grigory; McDevitt, Christopher; Srinivasan, Bhuvana

    2016-03-01

    Hydrodynamic mix can significantly degrade thermonuclear burn rate in an inertial confinement fusion (ICF) target. Successful mitigation requires a detailed understanding of the physical mechanisms by which mix affects burn. Here we summarize the roles of three distinct plasma physics effects on burn rate. The first is the well-known effect of enhanced thermal energy loss from the hot spot and the mitigating role of self-generated or externally-applied magnetic field. The second is the fuel ion separation via inter-species ion diffusion driven by the powerful thermodynamic forces exacerbated by mix during the implosion process. The third is the fusion reactivity modification by fast ion transport in a mix-dominated ICF target, where hot plasma is intermingled with cold fuel.

  20. Health professionals' and consumers' opinion: what is considered important when rating burn scars from photographs?

    PubMed

    Simons, Megan; Tyack, Zephanie

    2011-01-01

    With advances in wound care technology, there is a trend toward patients undertaking specialist burns treatment in an outpatient capacity. Photographic scar evaluation is a part of this trend in some health services because it permits scar assessment by different health professionals, both within and across outpatient services, to assess the impact of scar management strategies. The aim of this study was to explore the parameters considered integral to scar assessment when completing photographic scar evaluation. First, opinions were sought from 38 burn health professionals in 2 tertiary pediatric hospitals who participated in focus groups where in-person and in-photograph scar rating were completed using three burn scar rating scales (modified Vancouver scar scale, Manchester scar scale, and patient and observer scar assessment scale) presented with a standard format and instructions. Second, 36 occupational therapists and physiotherapists from Australia and New Zealand completed questionnaires. Third, 10 healthcare consumers from 1 tertiary pediatric hospital participated in face-to-face or telephone interviews. Parameters believed to be assessed using photographic evaluation of burns scarring were vascularity, surface area, color, contour, height, and overall opinion. However, surface area was considered questionable as an indicator of scar maturity. These parameters mostly differ from those considered important in a burn scar outcome measure when rating scars in-person: height/thickness, vascularity, color, pliability, joint function, and patient/client opinion. A categorical scale with visual descriptors, as well as specific strategies to improve photographic technique, may go some way to addressing the perceived difficulty in rating these parameters using burn scar photographs.

  1. Comparison of soil infiltration rates in burned and unburned mountainous watersheds

    USGS Publications Warehouse

    Martin, D.A.; Moody, J.A.

    2001-01-01

    Steady-state infiltration measurements were made at mountainous sites in New Mexico and Colorado, USA, with volcanic and granitic soils after wildfires and at comparable unburned sites. We measured infiltration in the New Mexico volcanic soils under two vegetation types, ponderosa pine and mixed conifer, and in the Colorado granitic soils under ponderosa pine vegetation. These measurements were made within high-severity burn areas using a portable infiltrometer with a 0.017 m2 infiltration area and artificial rainfall rates ranging from 97 to 440 mm h-1. Steady-state infiltration rates were less at all burned sites relative to unburned sites. The volcanic soil with ponderosa pine vegetation showed the greatest difference in infiltration rates with a ratio of steady-state infiltration rate in burned sites to unburned soils equal to 0.15. Volcanic soils with mixed conifer vegetation had a ratio (burned to unburned soils) of at most 0.38, and granitic soils with ponderosa pine vegetation had a ratio of 0.38. Steady-state infiltration rates on unburned volcanic and granitic soils with ponderosa pine vegetation are not statistically different. We present data on the particle-size distribution at all the study sites and examples of wetting patterns produced during the infiltration experiments. Published in 2001 by John Wiley and Sons, Ltd.

  2. What could have caused pre-industrial biomass burning emissions to exceed current rates?

    NASA Astrophysics Data System (ADS)

    van der Werf, G. R.; Peters, W.; van Leeuwen, T. T.; Giglio, L.

    2012-08-01

    is considered "the burning continent". Our new modelling results, together with existing literature, indicate that no definitive conclusions can be drawn about unprecedentedly high or low biomass burning rates from current data analyses.

  3. What could have caused pre-industrial biomass burning emissions to exceed current rates?

    NASA Astrophysics Data System (ADS)

    van der Werf, G. R.; Peters, W.; van Leeuwen, T. T.; Giglio, L.

    2013-01-01

    ; satellite data indicates that the majority of savannas have not burned in the past 10 yr, even in Africa, which is considered "the burning continent". Although we have not considered increased charcoal burning or changes in OH concentrations as potential causes for the elevated CO concentrations found at SPO, it is unlikely they can explain the large increase found in the CO concentrations in ice core data. Confirmation of the CO ice core data would therefore call for radical new thinking about causes of variable global fire rates over recent centuries.

  4. An Experiment to Demonstrate How a Catalyst Affects the Rate of a Reaction

    NASA Astrophysics Data System (ADS)

    Copper, Christine L.; Koubek, Edward

    1999-12-01

    By performing this experiment, students in general and introductory physical chemistry can learn more about the effect of a catalyst on a chemical reaction. This experiment, which is a modified version of the traditional iodine clock reaction, allows students to calculate rates of reaction, orders of reactants, and activation energies. It also lets students discover that to increase a reaction's rate, a catalyst need only provide any additional pathway for the reaction, not necessarily a pathway having a lower activation energy. This experiment is designed so that students will notice that the amount of catalyst used is important. Furthermore, the slight amount (~10-5 M MoO42-) of catalyst needed to increase the overall reaction rate and the abrupt color change that occurs seem to pique the interest of our students.

  5. Impact of oxidation catalysts on exhaust NO2/NOx ratio from lean-burn natural gas engines.

    PubMed

    Olsen, Daniel B; Kohls, Morgan; Arney, Gregg

    2010-07-01

    Oxides of nitrogen (NOx) emitted from internal combustion engines are composed primarily of nitric oxide (NO) and nitrogen dioxide (NO2). Exhaust from most combustion sources contains NOx composed primarily of NO. There are two important scenarios specific to lean-burn natural gas engines in which the NO2/NOx ratio can be significant: (1) when the engine is operated at ultralean conditions and (2) when an oxidation catalyst is used. Large NO2/NOx ratios may result in additional uncertainty in NOx emissions measurements because the most common technique (chemiluminescence) was developed for low NO2/NOx ratios. In this work, scenarios are explored in which the NO2/NOx ratio can be large. Additionally, three NOx measurement approaches are compared for exhaust with various NO2/NOx ratios. The three measurement approaches are chemiluminescence, chemical cell, and Fourier-transform infrared spectroscopy. A portable analyzer with chemical cell technology was found to be the most accurate for measuring exhaust NOx with large NO2/NOx ratios.

  6. The effect of levamisole on mortality rate among patients with severe burn injuries

    PubMed Central

    Fatemi, Mohammad Javad; Salehi, Hamid; Akbari, Hossein; Alinejad, Faranak; Saberi, Mohsen; Mousavi, Seyed Jaber; Soltani, Majid; Taghavi, Shahrzad; Payandan, Hossein

    2013-01-01

    Background: Burn injuries are one of the main causes of mortality and morbidity throughout the world and burn patients have higher chances for infection due to their decreased immune resistance. Levamisole, as an immunomodulation agent, stimulates the immune response against infection. Materials and Methods: This randomized clinical trial was conducted in Motahari Burn Center, Tehran, Iran. Patients who had second- or third-degree burn with involvement of more than 50% of total body surface area (TBSA) were studied. The levamisole group received levamisole tablet, 100 mg per day. Meantime, both the levamisole and control groups received the standard therapy of the Burn Center, based on a standard protocol. Then, the outcome of the patients was evaluated. Results: 237 patients entered the study. After excluding 42 patients with inhalation injury, electrical and chemical burns, and the patients who died in the first 72 h, 195 patients remained in the study, including 110 patients in the control group and 85 in the treatment group. The mean age of all patients (between 13 to 64 years) was 33.29 ± 11.39 years (Mean ± SD), and it was 33.86 ± 11.45 years in the control group and 32.57 ± 11.32 years in the treatment group. The mean percentage of TBSA burn was 64.50 ± 14.34 and 68.58 ± 14.55 for the levamisole and control groups, respectively, with the range of 50-100% and 50-95% TBSA. The mortality rate was 68 (61.8%) patients in the control group and 50 (58.8%) patients in the treatment group (P = 0.8). Conclusion: According to this study, there was no significant relationship between improvement of mortality and levamisole consumption. PMID:24381625

  7. EFFECTS OF BURN RATE, WOOD SPECIES, MOISTURE CONTENT AND WEIGHT OF WOOD LOADED ON WOODSTOVE EMISSIONS

    EPA Science Inventory

    The report gives results of tests of four woodstove operating parameters (burn rate, wood moisture, wood load, and wood species) at two levels each using a half factorial experimental test design to determine statistically significant effects on the emission components CO, CO2, p...

  8. EFFECTS OF BURN RATE, WOOD SPECIES, MOISTURE CONTENT AND WEIGHT OF WOOD LOADED ON WOODSTOVE EMISSIONS

    EPA Science Inventory

    The report gives results of tests of four woodstove operating parameters (burn rate, wood moisture, wood load, and wood species) at two levels each using a half factorial experimental test design to determine statistically significant effects on the emission components CO, CO2, p...

  9. NOx abatement in the exhaust of lean-burn natural gas engines over Ag-supported γ-Al2O3 catalysts

    NASA Astrophysics Data System (ADS)

    Azizi, Y.; Kambolis, A.; Boréave, A.; Giroir-Fendler, A.; Retailleau-Mevel, L.; Guiot, B.; Marchand, O.; Walter, M.; Desse, M.-L.; Marchin, L.; Vernoux, P.

    2016-04-01

    A series of Ag catalysts supported on γ-Al2O3, including two different γ-Al2O3 supports and various Ag loadings (2-8 wt.%), was prepared, characterized (SEM, TEM, BET, physisorption, TPR, NH3-TPD) and tested for the selective catalytic reduction of NOx by CH4 for lean-burn natural gas engines exhausts. The catalysts containing 2 wt.% Ag supported on γ-Al2O3 were found to be most efficient for the NOx reduction into N2 with a maximal conversion of 23% at 650 °C. This activity was clearly linked with the ability of the catalyst to concomitantly produce CO, via the methane steam reforming, and NO2. The presence of small AgOx nanoparticles seems to be crucial for the methane activation and NOx reduction.

  10. Laminar burn rates of gun propellants measured in the high-pressure strand burner

    SciTech Connect

    Reaugh, J. E., LLNL

    1997-10-01

    The pressure dependence of the laminar burn rate of gun propellants plays a role in the design and behavior of high-performance guns. We have begun a program to investigate the effects of processing variables on the laminar burn rates, using our high-pressure strand burner to measure these rates at pressures exceeding 700 MPa. We have burned JA2 and M43 propellant samples, provided by Dr. Arpad Juhasz, ARL, from propellant lots previously used in round-robin tests. Our results at room temperature are in accord with other measurements. In addition, we present results measured for propellant that has been preheated to 50 C before burning. We used our thermochemical equilibrium code, CHEETAH, to help interpret the simultaneous pressure and temperature measurements taken during the testing, and show examples of its use. It has been modified to provide performance measures and equations of state for the products that are familiar to the gun-propellant community users of BLAKE.

  11. Impacts of halogen additions on mercury oxidation, in a slipstream selective catalyst reduction (SCR), reactor when burning sub-bituminous coal.

    PubMed

    Cao, Yan; Gao, Zhengyang; Zhu, Jiashun; Wang, Quanhai; Huang, Yaji; Chiu, Chengchung; Parker, Bruce; Chu, Paul; Pant, Wei-Ping

    2008-01-01

    This paper presents a comparison of impacts of halogen species on the elemental mercury (Hg(0)) oxidation in a real coal-derived flue gas atmosphere. It is reported there is a higher percentage of Hg(0) in the flue gas when burning sub-bituminous coal (herein Powder River Basin (PRB) coal) and lignite, even with the use of selective catalytic reduction (SCR). The higher Hg(0)concentration in the flue gas makes it difficult to use the wet-FGD process for the mercury emission control in coal-fired utility boilers. Investigation of enhanced Hg(0) oxidation by addition of hydrogen halogens (HF, HCl, HBr, and HI) was conducted in a slipstream reactor with and without SCR catalysts when burning PRB coal. Two commercial SCR catalysts were evaluated. SCR catalyst no. 1 showed higher efficiencies of both NO reduction and Hg(0) oxidation than those of SCR catalyst no. 2. NH3 addition seemed to inhibit the Hg(0) oxidation, which indicated competitive processes between NH3 reduction and Hg(0) oxidation on the surface of SCR catalysts. The hydrogen halogens, in the order of impact on Hg(0) oxidation, were HBr, HI, and HCl or HF. Addition of HBr at approximately 3 ppm could achieve 80% Hg(0) oxidation. Addition of HI at approximately 5 ppm could achieve 40% Hg(0) oxidation. In comparison to the empty reactor, 40% Hg(0) oxidation could be achieved when HCl addition was up to 300 ppm. The enhanced Hg(0) oxidation by addition of HBr and HI seemed not to be correlated to the catalytic effects by both evaluated SCR catalysts. The effectiveness of conversion of hydrogen halogens to halogen molecules or interhalogens seemed to be attributed to their impacts on Hg(0) oxidation.

  12. Impacts of halogen additions on mercury oxidation, in a slipstream selective catalyst reduction (SCR), reactor when burning sub-bituminous coal

    SciTech Connect

    Yan Cao; Zhengyang Gao; Jiashun Zhu; Quanhai Wang; Yaji Huang; Chengchung Chiu; Bruce Parker; Paul Chu; Wei-ping Pan

    2008-01-01

    This paper presents a comparison of impacts of halogen species on the elemental mercury (Hg(0)) oxidation in a real coal-derived flue gas atmosphere. It is reported there is a higher percentage of Hg(0) in the flue gas when burning sub-bituminous coal (herein Powder River Basin (PRB) coal) and lignite, even with the use of selective catalytic reduction (SCR). The higher Hg(0) concentration in the flue gas makes it difficult to use the wet-FGD process for the mercury emission control in coal-fired utility boilers. Investigation of enhanced Hg(0) oxidation by addition of hydrogen halogens (HF, HCl, HBr, and HI) was conducted in a slipstream reactor with and without SCR catalysts when burning PRB coal. Two commercial SCR catalysts were evaluated. SCR catalyst no. 1 showed higher efficiencies of both NO reduction and Hg(0) oxidation than those of SCR catalyst no. 2. NH{sub 3} addition seemed to inhibit the Hg(0) oxidation, which indicated competitive processes between NH{sub 3} reduction and Hg(0) oxidation on the surface of SCR catalysts. The hydrogen halogens, in the order of impact on Hg(0) oxidation, were HBr, HI, and HCl or HF. Addition of HBr at approximately 3 ppm could achieve 80% Hg(0) oxidation. Addition of HI at approximately 5 ppm could achieve 40% Hg(0) oxidation. In comparison to the empty reactor, 40% Hg(0) oxidation could be achieved when HCl addition was up to 300 ppm. The enhanced Hg(0) oxidation by addition of HBr and HI seemed not to be correlated to the catalytic effects by both evaluated SCR catalysts. The effectiveness of conversion of hydrogen halogens to halogen molecules or interhalogens seemed to be attributed to their impacts on Hg(0) oxidation. 30 refs., 4 figs.

  13. Understanding Rate Acceleration and Stereoinduction of an Asymmetric Giese Reaction Mediated by a Chiral Rhodium Catalyst.

    PubMed

    Tutkowski, Brandon; Meggers, Eric; Wiest, Olaf

    2017-06-21

    The surprising acceleration of the addition of electron-rich radicals to α,β-unsaturated 2-acyl imidazoles by a chiral-at-metal rhodium catalyst is investigated. M06/Lanl2DZ (Rh),6-31G(d) calculations reproduce the observed rate acceleration and shed light on a catalyst design where a rigid chiral pocket with a steric interaction >5 Å from the chiral metal center leads to the observed high stereoinduction. Analysis of the molecular orbitals of two key addition transition states emphasize the role of the catalyst as a Lewis acid without significant charge transfer.

  14. Different growth rates for catalyst-induced and self-induced GaN nanowires

    NASA Astrophysics Data System (ADS)

    Chèze, C.; Geelhaar, L.; Jenichen, B.; Riechert, H.

    2010-10-01

    The catalyst- and self-induced pathways of GaN nanowire growth by molecular beam epitaxy are compared. The catalyst-induced nanowires elongate faster than the self-induced ones and their growth rate is fully determined by the impinging N rate. The self-induced nanowire growth rate is identical on both Si(111) and Si(001) and approaches the impinging N rate only for the few longest nanowires. This difference is attributed to the presence of the Ni-catalyst which enhances the incorporation of Ga at the nanowire tip while for the self-induced nanowires, growth is limited by the different incorporation rates on the nanowire tip and sidewall facets.

  15. Erosive Augmentation of Solid Propellant Burning Rate: Motor Size Scaling Effect

    NASA Technical Reports Server (NTRS)

    Strand, L. D.; Cohen, Norman S.

    1990-01-01

    Two different independent variable forms, a difference form and a ratio form, were investigated for correlating the normalized magnitude of the measured erosive burning rate augmentation above the threshold in terms of the amount that the driving parameter (mass flux or Reynolds number) exceeds the threshold value for erosive augmentation at the test condition. The latter was calculated from the previously determined threshold correlation. Either variable form provided a correlation for each of the two motor size data bases individually. However, the data showed a motor size effect, supporting the general observation that the magnitude of erosive burning rate augmentation is reduced for larger rocket motors. For both independent variable forms, the required motor size scaling was attained by including the motor port radius raised to a power in the independent parameter. A boundary layer theory analysis confirmed the experimental finding, but showed that the magnitude of the scale effect is itself dependent upon scale, tending to diminish with increasing motor size.

  16. An Experiment To Demonstrate How a Catalyst Affects the Rate of a Reaction.

    ERIC Educational Resources Information Center

    Copper, Christine L.; Koubeck, Edward

    1999-01-01

    Describes a chemistry experiment that allows students to calculate rates of reaction, orders of reaction, and activation energies. The activity demonstrates that to increase a reaction's rate, a catalyst need only provide any additional pathway for the reaction, not necessarily a pathway having lower activation energy. (WRM)

  17. An Experiment To Demonstrate How a Catalyst Affects the Rate of a Reaction.

    ERIC Educational Resources Information Center

    Copper, Christine L.; Koubeck, Edward

    1999-01-01

    Describes a chemistry experiment that allows students to calculate rates of reaction, orders of reaction, and activation energies. The activity demonstrates that to increase a reaction's rate, a catalyst need only provide any additional pathway for the reaction, not necessarily a pathway having lower activation energy. (WRM)

  18. The influence of fuel mass load, oxygen supply and burning rate on emission factor and size distribution of carbonaceous particulate matter from indoor corn straw burning

    PubMed Central

    Shen, Guofeng; Xue, Miao; Wei, Siye; Chen, Yuanchen; Wang, Bing; Wang, Rong; Shen, Huizhong; Li, Wei; Zhang, Yanyan; Huang, Ye; Chen, Han; Wei, Wen; Zhao, Qiuyue; Li, Bin; Wu, Haisuo; Tao, Shu

    2014-01-01

    The uncertainty in emission estimation is strongly associated with the variation in emission factor which could be influenced by a variety of factors, like fuel property, stove type, fire management and even methods used in measurements. The impacts of these factors were usually complicated and often interacted with each other. In the present study, controlled burning experiments were conducted to investigate the influence of fuel mass load, air supply and burning rate on the emission of carbonaceous particulate matter (PM) from indoor corn straw burning. Their impacts on PM size distribution were also studied. The results showed that EFs of PM (EFPM), organic carbon (EFOC) and element carbon (EFEC) was independent of the fuel mass load. The differences among them under different burning rates or air supply amounts were also found to be insignificant (p > 0.05) in the tested circumstances. PM from the indoor corn straw burning was dominated by fine PM, and PM with diameter less than 2.1 μm contributed about 86.4±3.9% of the total. The size distribution of PM was also influenced by the burning rate and changed air supply conditions. On average, EFPM, EFOC and EFEC for corn straw burned in a residential cooking stove were 3.84±1.02, 0.846±0.895 and 0.391±0.350 g/kg, respectively. EFPM, EFOC and EFEC were found to be positively correlated with each other, but they were not significantly correlated with EF of co-emitted CO, suggesting a special attention should be paid to the use of CO acting as a surrogate for other incomplete pollutants. PMID:23923424

  19. Oxidation catalyst

    DOEpatents

    Ceyer, Sylvia T.; Lahr, David L.

    2010-11-09

    The present invention generally relates to catalyst systems and methods for oxidation of carbon monoxide. The invention involves catalyst compositions which may be advantageously altered by, for example, modification of the catalyst surface to enhance catalyst performance. Catalyst systems of the present invention may be capable of performing the oxidation of carbon monoxide at relatively lower temperatures (e.g., 200 K and below) and at relatively higher reaction rates than known catalysts. Additionally, catalyst systems disclosed herein may be substantially lower in cost than current commercial catalysts. Such catalyst systems may be useful in, for example, catalytic converters, fuel cells, sensors, and the like.

  20. Evaluation of magnesium-aluminum eutectic to improve combustion efficiency in low burning rate propellants

    NASA Technical Reports Server (NTRS)

    Northam, B. G.; Sullivan, E. M.

    1973-01-01

    A previous investigation indicated that combustion efficiency of low burning-rate propellants could be improved if the aluminum fuel was replaced by aluminum particles coated with a magnesium-aluminum eutectic alloy (ALCAL). The purpose of the present investigation was to evaluate the possibility of improving the combustion efficiency of these propellants by admixing the eutectic with the aluminum rather than coating the aluminum. Tests of three propellants similar in every respect except for the metal fuel were conducted in test motors with 4.54 kg (10 lbm) of propellant. The first propellant used aluminum fuel; the second contained aluminum admixed with magnesium-aluminum eutectic; the third used ALCAL. The test results show the the admixed fuel gave better low burning-rate combustion efficiency than the other two. The test results also showed that the ALCAL was deficient in that much, if not all, of the coating material could be found as the fine particles in a bimodal mix of aluminum and eutectic. The combustion efficiency of low burning-rate aluminized propellants can be significantly improved by mixing a small amount of magnesium-aluminum alloy with the aluminum fuel.

  1. The effect of density and thermal diffusivity of wood on the rate of burning of wood cribs

    Treesearch

    H.D. Bruce; W.Y. Pong; W.L. Fons

    1961-01-01

    A program of research on free-burning wood fires is being conducted by the Forest Service to build up experimental data on the properties of such fires, with the iltimate objective of describing the physical phenomena in terms of fundamental laws. Density was the first wood property investigated. This report gives data on the rate of burning of cribs of five species...

  2. Rate-equation model for multi-mode semiconductor lasers with spatial hole burning.

    PubMed

    Lenstra, Daan; Yousefi, Mirvais

    2014-04-07

    We present a set of rate equations for the modal amplitudes and carrier-inversion moments that describe the deterministic multi-mode dynamics of a semiconductor laser due to spatial hole burning. Mutual interactions among the lasing modes, induced by high- frequency modulations of the carrier distribution, are included by carrier-inversion moments for which rate equations are given as well. We derive the Bogatov effect of asymmetric gain suppression in semiconductor lasers and illustrate the potential of the model for a two and three-mode laser by numerical and analytical methods.

  3. Rates of post-fire vegetation recovery and fuel accumulation as a function of burn severity and time-since-burn in four western U.S. ecosystems

    USDA-ARS?s Scientific Manuscript database

    Vegetation recovery and fuel accumulation rates following wildfire are useful measures of ecosystem resilience, yet few studies have quantified these variables over 10 years post-fire. Conventional wisdom is that recovery time to pre-fire condition will be slower as a function of burn severity, as i...

  4. A compact, rugged, high repetition rate CO2 laser incorporating catalyst

    NASA Technical Reports Server (NTRS)

    Schwarzenberger, P. M.; Matzangou, X.

    1990-01-01

    The principal design features and operating characteristics of a high repetition rate CO2 laser are outlined. The laser is a compact, rugged unit, completely sealed and incorporating an unheated solid catalyst. Stable operation has been successfully demonstrated over a temperature range of -35 C to 65 C.

  5. Fischer Tropsch synthesis : influence of Mn on the carburization rates and activities of Fe-based catalysts by TPR-EXAFS/XANES and catalyst testing.

    SciTech Connect

    Ribeiro, M. C.; Jacobs, G.; Pendyala, R.; Davis, B. H.; Cronauer, D. C.; Kropf, A. J.; Marshall, C. L.

    2011-03-24

    Fe-based catalysts containing different amounts of Mn were tested for Fischer-Tropsch synthesis using a stirred tank reactor at 270 C, 1.21 MPa, and H{sub 2}:CO = 0.7. Catalyst activation by carburization with 10% CO/He was followed by Temperature Programmed Reduction/X-ray Absorption Spectroscopy (TPR-EXAFS/XANES) from room temperature to 300 C. {gamma}-Fe{sub 2}O{sub 3} was converted into iron carbides, whereas MnO{sub x} was reduced to oxygen deficient MnO. Mn hindered Fe carburization, such that the carburized catalyst displayed higher Fe{sub 3}O{sub 4} content than the catalyst without Mn. EXAFS fitting indicates that the carburized catalyst contained a mixture of Hgg carbide, Fe{sub 3}O{sub 4}, and Mn oxides. Increasing Mn content led to higher CH{sub 4} and light product selectivities, and lower light olefin selectivities. Higher and stable conversions were obtained with a catalyst containing an almost equimolar Fe/Mn ratio relative to the catalyst without Mn. Selectivity trends are attributed to the higher WGS rates observed on the FeMn catalysts, consistent with the structural differences observed.

  6. Faster rates with less catalyst in template-directed reactions

    NASA Technical Reports Server (NTRS)

    Kanavarioti, A.; Baird, E. E.

    1995-01-01

    We have recently shown that the polycytidylic acid-directed polymerization of guanosine 5'-monophosphate 2-methylimidazolide (2-MeImpG) is amenable to kinetic study and that rate determinations as a function of 2-MeImpG concentration can reveal much mechanistic detail (Kanavarioti et al. 1993). Here we report kinetic data which show that, once the reaction has been initiated by the formation of dimers, the elongation of dimers to form longer oligomers is accelerated by decreasing polycytidylate (poly(C)) concentration from 0.05 to 0.002 M. This result is consistent with the previously proposed mechanism. The increase in the observed pseudo-first order rate constant for formation of the trimer, k3', and the corresponding constant for formation of oligomers longer than the trimer, ki' (ki' is independent of oligomer length for i > or = 4), with decreasing template concentration for a given monomer concentration is attributed to an increase in template occupancy as template concentration is reduced.

  7. Modeling Fluid Resuscitation by Formulating Infusion Rate and Urine Output in Severe Thermal Burn Adult Patients: A Retrospective Cohort Study

    PubMed Central

    Luo, Qizhi; Li, Wei; Zou, Xin; Dang, Yongming; Wu, Jun

    2015-01-01

    Acute burn injuries are among the most devastating forms of trauma and lead to significant morbidity and mortality. Appropriate fluid resuscitation after severe burn, specifically during the first 48 hours following injury, is considered as the single most important therapeutic intervention in burn treatment. Although many formulas have been developed to estimate the required fluid amount in severe burn patients, many lines of evidence showed that patients still receive far more fluid than formulas recommend. Overresuscitation, which is known as “fluid creep,” has emerged as one of the most important problems during the initial period of burn care. If fluid titration can be personalized and automated during the resuscitation phase, more efficient burn care and outcome will be anticipated. In the present study, a dynamic urine output based infusion rate prediction model was developed and validated during the initial 48 hours in severe thermal burn adult patients. The experimental results demonstrated that the developed dynamic fluid resuscitation model might significantly reduce the total fluid volume by accurately predicting hourly urine output and has the potential to aid fluid administration in severe burn patients. PMID:26090415

  8. Modeling Fluid Resuscitation by Formulating Infusion Rate and Urine Output in Severe Thermal Burn Adult Patients: A Retrospective Cohort Study.

    PubMed

    Luo, Qizhi; Li, Wei; Zou, Xin; Dang, Yongming; Wang, Kaifa; Wu, Jun; Li, Yongqin

    2015-01-01

    Acute burn injuries are among the most devastating forms of trauma and lead to significant morbidity and mortality. Appropriate fluid resuscitation after severe burn, specifically during the first 48 hours following injury, is considered as the single most important therapeutic intervention in burn treatment. Although many formulas have been developed to estimate the required fluid amount in severe burn patients, many lines of evidence showed that patients still receive far more fluid than formulas recommend. Overresuscitation, which is known as "fluid creep," has emerged as one of the most important problems during the initial period of burn care. If fluid titration can be personalized and automated during the resuscitation phase, more efficient burn care and outcome will be anticipated. In the present study, a dynamic urine output based infusion rate prediction model was developed and validated during the initial 48 hours in severe thermal burn adult patients. The experimental results demonstrated that the developed dynamic fluid resuscitation model might significantly reduce the total fluid volume by accurately predicting hourly urine output and has the potential to aid fluid administration in severe burn patients.

  9. Predicted and Measured Effects of Pressure and Crossflow Velocity on Composite Propellant Burning Rate

    DTIC Science & Technology

    1980-12-01

    7~ SIECUq, ry CL AS51 FICATION Oir TIS1 PAGE II sitenlea.F e’ j -.,REPOR OUEt ibtRPA E" REA~D ISRC~iNS [)~)REP Auq 2I GOVT ACCESSION No. 3...crassflow veloCity’ oil propellant burning rate has beon developed and used P (over) DD I "j’ TA 4 1473 EDITION Of I NIOV465 It 01119LCI UNCLASSIFIEID q55_7...unreasonable. With substitution of (12) into (11), one finds: FH90= kQ p (dp 2 sin0) kiip dp 2 (13)•.sin0 as in the case of no crossflow. However, this

  10. Synthesis, characterization and evaluation of CO-oxidation catalysts for high repetition rate CO2 TEA lasers

    NASA Technical Reports Server (NTRS)

    Moser, Thomas P.

    1990-01-01

    An extremely active class of noble metal catalysts supported on titania was developed and fabricated at Hughes for the recombination of oxygen (O2) and carbon monoxide (CO) in closed-cycle CO2 TEA lasers. The incipient wetness technique was used to impregnate titania and alumina pellets with precious metals including platinum and palladium. In particular, the addition of cerium (used as an oxygen storage promoter) produced an extremely active Pt/Ce/TiO2 catalyst. By comparison, the complementary Pt/Ce/ gamma-Al2O3 catalyst was considerably less active. In general, chloride-free catalyst precursors proved critical in obtaining an active catalyst while also providing uniform metal distributions throughout the support structure. Detailed characterization of the Pt/Ce/TiO2 catalyst demonstrated uniform dendritic crystal growth of the metals throughout the support. Electron spectroscopy for Chemical Analysis (ESCA) analysis was used to characterize the oxidation states of Pt, Ce and Ti. The performance of the catalysts was evaluated with an integral flow reactor system incorporating real time analysis of O2 and CO. With this system, the transient and steady-state behavior of the catalysts were evaluated. The kinetic evaluation was complemented by tests in a compact, closed-cycle Hughes CO2 TEA laser operating at a pulse repetition rate of 100 Hz with a catalyst temperature of 75 to 95 C. The Pt/Ce/TiO2 catalyst was compatible with a C(13)O(16)2 gas fill.

  11. Synthesis, characterization and evaluation of CO-oxidation catalysts for high repetition rate CO2 TEA lasers

    NASA Astrophysics Data System (ADS)

    Moser, Thomas P.

    1990-06-01

    An extremely active class of noble metal catalysts supported on titania was developed and fabricated at Hughes for the recombination of oxygen (O2) and carbon monoxide (CO) in closed-cycle CO2 TEA lasers. The incipient wetness technique was used to impregnate titania and alumina pellets with precious metals including platinum and palladium. In particular, the addition of cerium (used as an oxygen storage promoter) produced an extremely active Pt/Ce/TiO2 catalyst. By comparison, the complementary Pt/Ce/ gamma-Al2O3 catalyst was considerably less active. In general, chloride-free catalyst precursors proved critical in obtaining an active catalyst while also providing uniform metal distributions throughout the support structure. Detailed characterization of the Pt/Ce/TiO2 catalyst demonstrated uniform dendritic crystal growth of the metals throughout the support. Electron spectroscopy for Chemical Analysis (ESCA) analysis was used to characterize the oxidation states of Pt, Ce and Ti. The performance of the catalysts was evaluated with an integral flow reactor system incorporating real time analysis of O2 and CO. With this system, the transient and steady-state behavior of the catalysts were evaluated. The kinetic evaluation was complemented by tests in a compact, closed-cycle Hughes CO2 TEA laser operating at a pulse repetition rate of 100 Hz with a catalyst temperature of 75 to 95 C. The Pt/Ce/TiO2 catalyst was compatible with a C(13)O(16)2 gas fill.

  12. THE IMPACT OF HELIUM-BURNING REACTION RATES ON MASSIVE STAR EVOLUTION AND NUCLEOSYNTHESIS

    SciTech Connect

    West, Christopher; Heger, Alexander; Austin, Sam M. E-mail: alexander.heger@monash.edu

    2013-05-20

    We study the sensitivity of presupernova evolution and supernova nucleosynthesis yields of massive stars to variations of the helium-burning reaction rates within the range of their uncertainties. The current solar abundances from Lodders are used for the initial stellar composition. We compute a grid of 12 initial stellar masses and 176 models per stellar mass to explore the effects of independently varying the {sup 12}C({alpha}, {gamma}){sup 16}O and 3{alpha} reaction rates, denoted R{sub {alpha},12} and R{sub 3{alpha}}, respectively. The production factors of both the intermediate-mass elements (A = 16-40) and the s-only isotopes along the weak s-process path ({sup 70}Ge, {sup 76}Se, {sup 80}Kr, {sup 82}Kr, {sup 86}Sr, and {sup 87}Sr) were found to be in reasonable agreement with predictions for variations of R{sub 3{alpha}} and R{sub {alpha},12} of {+-}25%; the s-only isotopes, however, tend to favor higher values of R{sub 3{alpha}} than the intermediate-mass isotopes. The experimental uncertainty (one standard deviation) in R{sub 3{alpha}}(R{sub {alpha},12}) is approximately {+-}10%({+-}25%). The results show that a more accurate measurement of one of these rates would decrease the uncertainty in the other as inferred from the present calculations. We also observe sharp changes in production factors and standard deviations for small changes in the reaction rates, due to differences in the convection structure of the star. The compactness parameter was used to assess which models would likely explode as successful supernovae, and hence contribute explosive nucleosynthesis yields. We also provide the approximate remnant masses for each model and the carbon mass fractions at the end of core-helium burning as a key parameter for later evolution stages.

  13. Reaction Rates for H-burning in Stars from Experiments with Radioactive Nuclear Beams

    NASA Astrophysics Data System (ADS)

    Trache, Livius

    2008-01-01

    In this lecture some of the indirect methods for nuclear astrophysics that can be applied to extract reaction rates for H-burning in stars are treated. Instead of reviewing all methods, I chose for exemplification four different experiments of our Texas A&M group, each involving a different method, but all related to the study of the proton rich nucleus 23Al. They involve the use of radioactive nuclear beams. I will describe the use of one-nucleon transfer reactions (the ANC method), breakup reactions at intermediate energies, β-decay and β-delayed proton-decay to extract nuclear structure information that is then used for nuclear astrophysics. I will show the specificities of each method, talk about their complementarities and redundancies.

  14. Thermal behaviors, nonisothermal decomposition reaction kinetics, thermal safety and burning rates of BTATz-CMDB propellant.

    PubMed

    Yi, Jian-Hua; Zhao, Feng-Qi; Wang, Bo-Zhou; Liu, Qian; Zhou, Cheng; Hu, Rong-Zu; Ren, Ying-Hui; Xu, Si-Yu; Xu, Kang-Zhen; Ren, Xiao-Ning

    2010-09-15

    The composite modified double base (CMDB) propellants (nos. RB0601 and RB0602) containing 3,6-bis (1H-1,2,3,4-tetrazol-5-yl-amino)-1,2,4,5-tetrazine (BTATz) without and with the ballistic modifier were prepared and their thermal behaviors, nonisothermal decomposition reaction kinetics, thermal safety and burning rates were investigated. The results show that there are three mass-loss stages in TG curve and two exothermic peaks in DSC curve for the BTATz-CMDB propellant. The first two mass-loss stages occur in succession and the temperature ranges are near apart, and the decomposition peaks of the two stages overlap each other, inducing only one visible exothermic peak appear in DSC curve during 350-550 K. The reaction mechanisms of the main exothermal decomposition processes of RB0601 and RB0602 are all classified as chemical reaction, the mechanism functions are f(alpha)=(1-alpha)(2), and the kinetic equations are dalpha/dt = 10(19.24)(1-alpha)(2)e(-2.32x10(4)/T) and dalpha/dt = 10(20.32)(1-alpha)(2)e(-2.32x10(4)/T). The thermal safety evaluation on the BTATz-CMDB propellants was obtained. With the substitution of 26% RDX by BTATz and with the help of the ballistic modifier in the CMDB propellant formulation, the burning rate can be improved by 89.0% at 8 MPa and 47.1% at 22 MPa, the pressure exponent can be reduced to 0.353 at 14-20 MPa. Copyright 2010 Elsevier B.V. All rights reserved.

  15. Calibration of reaction rates for the CREST reactive-burn model

    NASA Astrophysics Data System (ADS)

    Handley, Caroline

    2015-06-01

    In recent years, the hydrocode-based CREST reactive-burn model has had success in modelling a range of shock initiation and detonation propagation phenomena in polymer bonded explosives. CREST uses empirical reaction rates that depend on a function of the entropy of the non-reacted explosive, allowing the effects of initial temperature, porosity and double-shock desensitisation to be simulated without any modifications to the model. Until now, the sixteen reaction-rate coefficients have been manually calibrated by trial and error, using hydrocode simulations of a subset of sustained-shock initiation gas-gun experiments and the detonation size-effect curve for the explosive. This paper will describe the initial development of an automatic method for calibrating CREST reaction-rate coefficients, using the well-established Particle Swarm Optimisation (PSO) technique. The automatic method submits multiple hydrocode simulations for each ``particle'' and analyses the results to determine the ``misfit'' to gas-gun and size-effect data. Over ~40 ``generations,'' the PSO code finds a best set of reaction-rate coefficients that minimises the misfit. The method will be demonstrated by developing a new CREST model for EDC32, a conventional high explosive.

  16. Experimental Methodology for Estimation of Local Heat Fluxes and Burning Rates in Steady Laminar Boundary Layer Diffusion Flames

    PubMed Central

    Singh, Ajay V.; Gollner, Michael J.

    2016-01-01

    Modeling the realistic burning behavior of condensed-phase fuels has remained out of reach, in part because of an inability to resolve the complex interactions occurring at the interface between gas-phase flames and condensed-phase fuels. The current research provides a technique to explore the dynamic relationship between a combustible condensed fuel surface and gas-phase flames in laminar boundary layers. Experiments have previously been conducted in both forced and free convective environments over both solid and liquid fuels. A unique methodology, based on the Reynolds Analogy, was used to estimate local mass burning rates and flame heat fluxes for these laminar boundary layer diffusion flames utilizing local temperature gradients at the fuel surface. Local mass burning rates and convective and radiative heat feedback from the flames were measured in both the pyrolysis and plume regions by using temperature gradients mapped near the wall by a two-axis traverse system. These experiments are time-consuming and can be challenging to design as the condensed fuel surface burns steadily for only a limited period of time following ignition. The temperature profiles near the fuel surface need to be mapped during steady burning of a condensed fuel surface at a very high spatial resolution in order to capture reasonable estimates of local temperature gradients. Careful corrections for radiative heat losses from the thermocouples are also essential for accurate measurements. For these reasons, the whole experimental setup needs to be automated with a computer-controlled traverse mechanism, eliminating most errors due to positioning of a micro-thermocouple. An outline of steps to reproducibly capture near-wall temperature gradients and use them to assess local burning rates and heat fluxes is provided. PMID:27285827

  17. Experimental Methodology for Estimation of Local Heat Fluxes and Burning Rates in Steady Laminar Boundary Layer Diffusion Flames.

    PubMed

    Singh, Ajay V; Gollner, Michael J

    2016-06-01

    Modeling the realistic burning behavior of condensed-phase fuels has remained out of reach, in part because of an inability to resolve the complex interactions occurring at the interface between gas-phase flames and condensed-phase fuels. The current research provides a technique to explore the dynamic relationship between a combustible condensed fuel surface and gas-phase flames in laminar boundary layers. Experiments have previously been conducted in both forced and free convective environments over both solid and liquid fuels. A unique methodology, based on the Reynolds Analogy, was used to estimate local mass burning rates and flame heat fluxes for these laminar boundary layer diffusion flames utilizing local temperature gradients at the fuel surface. Local mass burning rates and convective and radiative heat feedback from the flames were measured in both the pyrolysis and plume regions by using temperature gradients mapped near the wall by a two-axis traverse system. These experiments are time-consuming and can be challenging to design as the condensed fuel surface burns steadily for only a limited period of time following ignition. The temperature profiles near the fuel surface need to be mapped during steady burning of a condensed fuel surface at a very high spatial resolution in order to capture reasonable estimates of local temperature gradients. Careful corrections for radiative heat losses from the thermocouples are also essential for accurate measurements. For these reasons, the whole experimental setup needs to be automated with a computer-controlled traverse mechanism, eliminating most errors due to positioning of a micro-thermocouple. An outline of steps to reproducibly capture near-wall temperature gradients and use them to assess local burning rates and heat fluxes is provided.

  18. Fire scar growth and closure rates in white oak (Quercus alba) and the implications for prescribed burning

    Treesearch

    Michael C. Stambaugh; Kevin T. Smith; Daniel C. Dey

    2017-01-01

    In burned forestlands, fire scar wounds commonly occur on tree stems as a result of cambial heating. In hardwood forests in particular, wounding can lead to stem decay with the extent of decay being related to scar size and exposure time. Therefore, wound closure rates are important to understand in the context of fire management such that allowing sufficient time for...

  19. Oxygen additive amount dependence of rate of photoresist removal by H radicals generated on a tungsten hot-wire catalyst

    NASA Astrophysics Data System (ADS)

    Yamamoto, Masashi; Umemoto, Hironobu; Ohdaira, Keisuke; Shikama, Tomokazu; Nishiyama, Takashi; Horibe, Hideo

    2016-07-01

    We examined an environmentally friendly photoresist removal method using radicals produced by decomposing mixtures of hydrogen and oxygen on a hot tungsten catalyst. The photoresist removal rate increased with the oxygen additive amount (the flow rate ratio of oxygen to hydrogen) up to an optimal amount and then decreased gradually. When the catalyst temperature was 1600 °C, the optimal oxygen additive amount was 1.0% and the removal rate was 1.7 times higher than that in the pure hydrogen system. At 2000 °C, the optimal amount increased to 2.5% but the increase ratio decreased by 1.3 times. At high catalyst temperatures, the absolute removal rate as well as the optimal oxygen additive amount is high, but the increase ratio is low. At the optimal oxygen additive amount, H, O, and OH radicals may exert their effects together to decompose photosensitive polymers.

  20. The effect of Burns & Wounds (B&W)/burdock leaf therapy on burn-injured Amish patients: a pilot study measuring pain levels, infection rates, and healing times.

    PubMed

    Kolacz, Nicole M; Jaroch, Mark T; Bear, Monica L; Hess, Rosanna F

    2014-12-01

    The purposes of this pilot study were to measure pain associated with dressing changes, assess the presence of infection, and document healing times of burn-injured Amish in central Ohio using an herbal therapy consisting of Burns and Wounds™ ointment (B&W) and burdock (Arctium ssp.) leaves. B&W contains honey, lanolin, olive oil, wheat germ oil, marshmallow root, Aloe vera gel, wormwood, comfrey root, white oak bark, lobelia inflata, vegetable glycerin, bees wax, and myrrh. A prospective, case series design guided the study within a community-based participatory research framework. Amish burn dressers provided burn care. Registered nurses monitored each case and documented findings. Pain scores were noted and burns were inspected for infection during dressing changes; healing times were measured from day of burn to complete closure of the skin. All cases were photographed. Between October 2011 and May 2013, five Amish were enrolled. All had first- and second-degree burns. B&W/burdock leaf dressing changes caused minimal or no pain; none of the burns became infected, and healing times averaged less than 14 days. The use of this herbal remedy appears to be an acceptable alternative to conventional burn care for these types of burns. The trauma of dressing changes was virtually nonexistent. Nurses working in communities with Amish residents should be aware of this herbal-based method of burn care and monitor its use when feasible. © The Author(s) 2014.

  1. Charcoal burning suicides in Hong Kong and urban Taiwan: an illustration of the impact of a novel suicide method on overall regional rates.

    PubMed

    Liu, Ka Y; Beautrais, Annette; Caine, Eric; Chan, Kathy; Chao, Anne; Conwell, Yeates; Law, Chikin; Lee, Dominic; Li, Pichiang; Yip, Paul

    2007-03-01

    Following the first case in Hong Kong in 1998, the method of committing suicide by charcoal burning has spread to other communities. This aim of this study was to examine the impact of charcoal burning suicides on both overall suicide rates and older-method suicide rates in Hong Kong and urban Taiwan. Trend analysis of the overall and method-specific suicide rates between 1997 and 2002. Comparison of age and gender profiles of those who committed suicide by charcoal burning and other methods of suicide. Hong Kong and Urban Taiwan. Suicides by charcoal burning increased rapidly within five years in both Hong Kong and urban Taiwan. This increase was not paralleled by decreases in suicides by older methods and led to an increase of more than 20% in the overall suicide rates. Those in the 24-39 age range were more likely to choose charcoal burning than other methods. The lack of parallel decreases in the suicides rates of older methods with the rise of charcoal burning suicides suggests limited substitution between the methods. The preponderance of the rise in suicide deaths associated with charcoal burning suggests that its invention, followed by wide media dissemination, may have specifically contributed to the increase in suicides in both regions. As a similar increase was found in urban Taiwan as in Hong Kong, charcoal burning suicide should not be viewed as merely a local health problem and has the potential to become a major public health threat in other countries.

  2. Use of Crystalline Boron as a Burn Rate Retardant Toward the Development of Green-Colored Handheld Signal Formulations

    DTIC Science & Technology

    2011-01-01

    Table 1 M125A1 baseline formulation Components Weight, % Barium Nitrate 46 Magnesium 30=50 33 Polyvinyl Chloride 16 Laminac 4116=Lupersol 5 Crystalline... polyvinyl chloride (PVC) is a known color enhancer and participated as a chlorine donor during the combustion process. Another reason for the utilization...Boron as a Burn Rate Retardant toward the Development of Green- Colored Handheld Signal Formulations Jesse J. Sabatini a , Jay C. Poret a & Russell N

  3. Convective Heat Transfer Scaling of Ignition Delay and Burning Rate with Heat Flux and Stretch Rate in the Equivalent Low Stretch Apparatus

    NASA Technical Reports Server (NTRS)

    Olson, Sandra

    2011-01-01

    To better evaluate the buoyant contributions to the convective cooling (or heating) inherent in normal-gravity material flammability test methods, we derive a convective heat transfer correlation that can be used to account for the forced convective stretch effects on the net radiant heat flux for both ignition delay time and burning rate. The Equivalent Low Stretch Apparatus (ELSA) uses an inverted cone heater to minimize buoyant effects while at the same time providing a forced stagnation flow on the sample, which ignites and burns as a ceiling fire. Ignition delay and burning rate data is correlated with incident heat flux and convective heat transfer and compared to results from other test methods and fuel geometries using similarity to determine the equivalent stretch rates and thus convective cooling (or heating) rates for those geometries. With this correlation methodology, buoyant effects inherent in normal gravity material flammability test methods can be estimated, to better apply the test results to low stretch environments relevant to spacecraft material selection.

  4. Turnover rate, reaction order, and elementary steps for the hydrodechlorination of chlorofluorocarbon compounds on palladium catalysts

    SciTech Connect

    Thompson, C.D.; Rioux, R.M.; Chen, N.; Ribeiro, F.H.

    2000-04-13

    The rates of hydrodechlorination catalyzed by Pd supported on carbon for four chlorofluorocarbons spanned a range of 7 orders of magnitude. The rates scaled up to the bond strength of the carbon-chlorine bond for the gas-phase reactant. This finding demonstrates that the rate-determining step involves the scission of the C-Cl bond and suggests, through Polanyi and linear free-energy relationships, that rates for other compounds can be estimated if the C-Cl bond strength is known. The reaction orders for the most abundant products are approximately first-order for the chlorine-containing compound, half-order in H{sub 2}, and inverse first-order in HCl. The reaction steps consistent with these orders include a rate-determining step involving the adsorption of the chlorofluorocarbon to a single site (which could be a single surface palladium atom) and equilibrated steps between gas-phase H{sub 2}, gas-phase HCl, and adsorbed hydrogen and chlorine atoms. The rates on the supported catalysts are comparable to the ones reported before on a Pd foil, indicating that the support does not play a role in the reaction. The product distribution is independent of conversion, implying that the various products are formed from a single visit of the reactant on the surface and not from readsorption of gas-phase products. The four compounds studied were chloropentafluoroethane (CF{sub 3}-CF{sub 2}Cl), 2-chloro-1,1,1,2-tetrafluoroethane (CF{sub 3}-CFClH), 1,1-dichlorotetrafluoroethane (CF{sub 3}-CFCl{sub 2}), and 1,1,1-trichloro-2,2,2-trifluoroethane (CF{sub 3}-CCl{sub 3}).

  5. Titanium subhydride potassium perchlorate (TiH1.65/KClO4) burn rates from hybrid closed bomb-strand burner experiments.

    SciTech Connect

    Cooper, Marcia A.; Oliver, Michael S.

    2012-08-01

    A hybrid closed bomb-strand burner is used to measure the burning behavior of the titanium subhydride potassium perchlorate pyrotechnic with an equivalent hydrogen concentration of 1.65. This experimental facility allows for simultaneous measurement of the closed bomb pressure rise and pyrotechnic burn rate as detected by electrical break wires over a range of pressures. Strands were formed by pressing the pyrotechnic powders to bulk densities between 60% and 90% theoretical maximum density. The burn rate dependance on initial density and vessel pressure are measured. At all initial strand densities, the burn is observed to transition from conductive to convective burning within the strand. The measured vessel pressure history is further analyzed following the closed bomb analysis methods developed for solid propellants.

  6. Self-deflagration rates of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB). [burning tate, thermal stability

    NASA Technical Reports Server (NTRS)

    Boggs, T. L.; Price, C. F.; Zurn, D. E.; Atwood, A. I.; Eisel, J. L.

    1980-01-01

    The thermal stability and resistance to impact was investigated for the ingredient TABA. Particular attention was given to determining the use of TABA as a possible alternative ingredient or substitute for HMX in explosives and high energy propellants. The burn rate of TABA was investigated as a function of pressure. It was concluded that the self deflagration rate of TABA is an order of magnitude lower than HMX over the range 2000-15000 psi; TABA will not sustain self deflagration at low pressures (less than or equal to 1500 psi) in the sample configuration and apparatus used.

  7. Self-deflagration rates of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB). [burning tate, thermal stability

    NASA Technical Reports Server (NTRS)

    Boggs, T. L.; Price, C. F.; Zurn, D. E.; Atwood, A. I.; Eisel, J. L.

    1980-01-01

    The thermal stability and resistance to impact was investigated for the ingredient TABA. Particular attention was given to determining the use of TABA as a possible alternative ingredient or substitute for HMX in explosives and high energy propellants. The burn rate of TABA was investigated as a function of pressure. It was concluded that the self deflagration rate of TABA is an order of magnitude lower than HMX over the range 2000-15000 psi; TABA will not sustain self deflagration at low pressures (less than or equal to 1500 psi) in the sample configuration and apparatus used.

  8. Comparison of iso-octane burning rates between single-phase and two-phase combustion for small droplets

    SciTech Connect

    Lawes, M.; Lee, Y.; Marquez, N.

    2006-02-01

    Two-phase combustion is a widespread mechanism of energy conversion that is of practical importance in gas turbines, diesel and spark ignition engines, furnaces, and hazardous environments. However, the exploration of important parameters in combustion systems of practical application is difficult, due to the multiplicity of dependent variables. In the present work, combustion rates of well-defined droplet suspensions of iso-octane have been measured using techniques employed for gaseous combustion. This required a full characterization of the aerosols produced in the combustion apparatus, which determined that the maximum droplet size produced was around 30 {mu}m. Comparisons of two-phase with single-phase laminar mixtures suggest that there were negligible differences in the burning velocity of an aerosol and a gaseous mixture at the same overall equivalence ratio and similar conditions for iso-octane. At high stretch rates, flames remained smooth and droplet enhancement was negligible. However, at lower rates of stretch, both gaseous and aerosol flames became unstable and cellular, and this cellularity, in some cases, increased the burning rate. The values of Markstein length measured for aerosol flames had trends similar to those for gaseous-phase mixtures (Markstein length decreased with equivalence ratio), but were lower than in gaseous combustion. The values of Markstein length in aerosol flames also decreased with liquid equivalence ratio and/or Sauter mean diameter. All this indicates a higher tendency to instabilities in aerosol flames compared to gaseous combustion. A qualitative explanation for the lower values of Markstein length in aerosol combustion is given. It is suggested in the present work that aerosol flames became unstable, and hence had faster burning rates, under conditions that would not result in unstable gaseous flames. Comparisons, qualitative and in terms of dimensionless groups, of two-phase with single-phase turbulent combustion also

  9. Burns - resources

    MedlinePlus

    Resources - burns ... The following organizations are good resources for information on burns : Burns Recovered -- brsg.org Model Systems Knowledge Translation Center - Burn Model Systems -- www.msktc.org/burn

  10. Investigation of Biomass Combustion Rate of Fire Radiative Energy Using Multiple-Satellite-observed Active Fires and Landsat TM Burn Severities across the Continental United States

    NASA Astrophysics Data System (ADS)

    Li, F.; Zhang, X.; Kondragunta, S.

    2015-12-01

    Biomass burning is a major source of atmospheric aerosol and greenhouse gases that substantially influence climate and regional air quality. However, the accuracy of biomass burning emissions estimated using traditional method is limited by large uncertainties in burned area and fuel loading. Alternatively, fire radiative energy (FRE) has recently been demonstrated to be linearly related to biomass combustion, which potentially improves the estimation of biomass burning emissions. The FRE-based combustion rate is 0.368-0.453 kg/MJ according to field controlled experiments while it varies from 1.37-4.5 kg/MJ derived from satellite-based bottom-up and top-down aerosol optical thickness estimates. Here we investigate the FRE combustion rate in over 1000 burn scars from 2011 to 2012 across the Continental United States (CONUS). Specifically, FRE was calculated by combining the high spatial observations from the Moderate Resolution Imaging Spectroradiometer (MODIS) and the high temporal observations from the Geostationary Operational Environmental Satellite (GOES). Biomass consumption in burn scars was modeled using Landsat TM 30m burn severities, 30m fuel loading from Fuel Characteristic Classification System, and combustion completeness compiled from recent literatures. The combustion rate was then investigated by correlating FRE to biomass consumption across CONUS and Bailey's ecoregions. Our results show that the combustion rate can be extracted from the linear relationship between biomass consumption and FRE. The combustion rate is 0.415±10% kg/MJ across CONUS, which is similar to the rate derived from field experiments. However, it varies from 0.18-1.9 kg/MJ among ecoregions. This implies that a single combustion rate could produce large uncertainty in the estimation of biomass consumption at large scales. We suggest that ecoregion specified combustion rates should help to improve the accuracy of quantifying biomass burning emissions regionally and globally.

  11. High-nitrogen-metal complexes as burning-rate modifiers for the aluminum-water propellant system

    SciTech Connect

    Tappan, Bryce C; Mason, Benjamin A

    2009-01-01

    The reactions of electropositive metals, such as aluminum, with water have long been utilized in explosive and propellant formulations, but until recently this has mostly been limited to the water formed as a product gas from the decomposition of another energetic system . Recently, however, with the increased availability of nano-particulate materials, the direct reaction of nano-aluminum (nAl) with water as an oxidizer has been investigated as a propellant system due to high reaction temperatures and the production of hydrogen as the primary gaseous species. This system could be useful for intra-planetary travel where non-terrestrial water is harvested for the oxidizer. Here we present the study of nAl, mixed at a stoichiometric ratio with water ({Phi} = 1) with the highly water soluble metal complexes of bis(tetrazolato)amine (BTA) added at 5, 15,30 and 50 wt% in the case of FeBTA and 5 and 15 wt% in the case of NiBTA and CoBTA. The basic structure of the BTA complexes is shown below where M = Fe, Ni or Co, and x = 3 for Fe and Co and x = 2 for Ni. The particle size of nAl studied was primarily 38 nm with various studies with the particle size of 80 nm. The FeBT A at a loading of 15 wt% gave the highest burning rate enhancement (4.6x at {approx}6.8 MPa), while retaining a low pressure exponent (0.21 compared to 0.24 for nA/H{sub 2}O). At 15 wt% the Ni and Co increased the burning rate, but also increased the pressure exponents. The burning rate of the FeBTA modified material with 80 nm Al decreased as the weight percent of FeBTA was increased, which also tracked decrease in the calculated specific impulse of the mixtures.

  12. Bimetallic Catalysts.

    ERIC Educational Resources Information Center

    Sinfelt, John H.

    1985-01-01

    Chemical reaction rates can be controlled by varying composition of miniscule clusters of metal atoms. These bimetallic catalysts have had major impact on petroleum refining, where work has involved heterogeneous catalysis (reacting molecules in a phase separate from catalyst.) Experimentation involving hydrocarbon reactions, catalytic…

  13. Bimetallic Catalysts.

    ERIC Educational Resources Information Center

    Sinfelt, John H.

    1985-01-01

    Chemical reaction rates can be controlled by varying composition of miniscule clusters of metal atoms. These bimetallic catalysts have had major impact on petroleum refining, where work has involved heterogeneous catalysis (reacting molecules in a phase separate from catalyst.) Experimentation involving hydrocarbon reactions, catalytic…

  14. Modeling rates of life form cover change in burned and unburned alpine heathland subject to experimental warming.

    PubMed

    Camac, James S; Williams, Richard J; Wahren, Carl-Henrik; Jarrad, Frith; Hoffmann, Ary A; Vesk, Peter A

    2015-06-01

    Elevated global temperatures are expected to alter vegetation dynamics by interacting with physiological processes, biotic relationships and disturbance regimes. However, few studies have explicitly modeled the effects of these interactions on rates of vegetation change, despite such information being critical to forecasting temporal patterns in vegetation dynamics. In this study, we build and parameterize rate-change models for three dominant alpine life forms using data from a 7-year warming experiment. These models allowed us to examine how the interactions between experimental warming, the abundance of bare ground (a measure of past disturbance) and neighboring life forms (a measure of life form interaction) affect rates of cover change in alpine shrubs, graminoids and forbs. We show that experimental warming altered rates of life form cover change by reducing the negative effects of neighboring life forms and positive effects of bare ground. Furthermore, we show that our models can predict the observed direction and rate of life form cover change at burned and unburned long-term monitoring sites. Model simulations revealed that warming in unburned vegetation is expected to result in increased forb and shrub cover and decreased graminoid cover. In contrast, in burned vegetation, warming is predicted to slow post-fire regeneration in both graminoids and forbs and facilitate rapid expansion in shrub cover. These findings illustrate the applicability of modeling rates of vegetation change using experimental data. Our results also highlight the need to account for both disturbance and the abundance of other life forms when examining and forecasting vegetation dynamics under climatic change.

  15. Charcoal burning suicides in Hong Kong and urban Taiwan: an illustration of the impact of a novel suicide method on overall regional rates

    PubMed Central

    Liu, Ka Y; Beautrais, Annette; Caine, Eric; Chan, Kathy; Chao, Anne; Conwell, Yeates; Law, Chikin; Lee, Dominic; Li, Pichiang; Yip, Paul

    2007-01-01

    Objectives Following the first case in Hong Kong in 1998, the method of committing suicide by charcoal burning has spread to other communities. This aim of this study was to examine the impact of charcoal burning suicides on both overall suicide rates and older‐method suicide rates in Hong Kong and urban Taiwan. Design Trend analysis of the overall and method‐specific suicide rates between 1997 and 2002. Comparison of age and gender profiles of those who committed suicide by charcoal burning and other methods of suicide. Setting Hong Kong and Urban Taiwan. Main results Suicides by charcoal burning increased rapidly within five years in both Hong Kong and urban Taiwan. This increase was not paralleled by decreases in suicides by older methods and led to an increase of more than 20% in the overall suicide rates. Those in the 24–39 age range were more likely to choose charcoal burning than other methods. Conclusions The lack of parallel decreases in the suicides rates of older methods with the rise of charcoal burning suicides suggests limited substitution between the methods. The preponderance of the rise in suicide deaths associated with charcoal burning suggests that its invention, followed by wide media dissemination, may have specifically contributed to the increase in suicides in both regions. As a similar increase was found in urban Taiwan as in Hong Kong, charcoal burning suicide should not be viewed as merely a local health problem and has the potential to become a major public health threat in other countries. PMID:17325404

  16. Experimental study on burning rates of square/rectangular gasoline and methanol pool fires under longitudinal air flow in a wind tunnel.

    PubMed

    Hu, L H; Liu, S; Peng, W; Huo, R

    2009-09-30

    Square pool fires with length of 5, 7.5, 10, 15, 20, 25 and 30 cm and rectangular pool fires with dimensions of 10 cm x 20 cm and 10 cm x 40 cm were burned in a wind tunnel, under a longitudinal air flow ranged from 0 to 3m/s with incremental change of about 0.5m/s. Methanol and gasoline were burned and compared, with results indicated that their burning rates showed different response to the longitudinal air flow. With the increase of the longitudinal air flow speed, the burning rates of methanol pool fires, except the 5 cm square one, first decreased and then increased, but those of the 5 cm methanol square one and the gasoline pool fires increased monotonously. The burning rate of smaller square pool fires increased more significantly than that of the larger ones, as well as the enlargement of their flame attachment length along the ground. The burning rate of a rectangular pool fire with longer rim parallel to the longitudinal flow increased faster, but the flame attachment length seemed to increase more gradually, with the increase of the longitudinal air flow speed than that perpendicular to.

  17. Ultrasonic measurements of burning rates in full-size rocket motors

    NASA Astrophysics Data System (ADS)

    Kurabayashi, H.; Sato, A.; Yamashita, K.; Nakayama, H.; Hori, K.; Honda, M.; Hasegawa, K.

    2011-10-01

    A new ultrasonic sounding technique to measure the instantaneous propellant thickness in a solid rocket motor has been developed and was used successfully in the static firing tests with full-size motors. The technique applies a low-frequency ultrasonic wave (50 or 100 kHz) [1, 2]. Sets of transducers were installed in the motor case using magnets, with each set comprising a transmitter/receiver and receivers. Transducer installation required careful setup to maintain good acoustic coupling between each transducer and motor case and to withstand the harsh vibrations of the environment. Time histories were obtained for the propellant thickness at various locations during the burning tests. This paper presents in detail the ultrasonic sounding and installation techniques and the results obtained.

  18. Fractal approach to the evaluation of burning rates in the vicinity of the piston in a spark-ignition engine

    SciTech Connect

    Foucher, F.; Mounaim-Rousselle, C.

    2005-11-01

    The burning rate in the vicinity of a piston is estimated from a fractal analysis. The fractal parameters are determined from laser sheet tomography flame images for methane-air mixtures with three equivalence ratios (1, 0.9, 0.8) in a transparent spark-ignition engine. Two imaging configurations were used: five horizontal planes placed at different distances from the piston (0, 1, 2, 3, and 5 mm) and a vertical one passed through the center of the combustion chamber. The methodology proposed by Foucher et al. [F. Foucher, S. Burnel, C. Mounaim-Rousselle, Proc. Combust. Inst. 29 (2002) 751-757] allows the effect of cyclic variations to be avoided. The fractal formulation is modified to take into account the flame-piston distance and flame quenching. Far from the piston, evolution of the fractal dimension versus q{sup '}/S{sub L}{sup 0} is found to be in good agreement with literature results. Near the piston, the fractal dimension evolves significantly when the distance is about twice the integral length scale and tends toward 2, the fractal dimension of a laminar flame front. The quenching ratio parameter Q{sub R} is introduced to consider the quenching of the flame by the piston. Finally, the burning rate is determined as a function of the distance between the wall and the mean flame contour and compared to a flame density approach, and similar results are found.

  19. Rate of contamination of hospital privacy curtains on a burns and plastic surgery ward: a cross-sectional study.

    PubMed

    Shek, K; Patidar, R; Kohja, Z; Liu, S; Gawaziuk, J P; Gawthrop, M; Kumar, A; Logsetty, S

    2017-05-01

    Surfaces in the patient environment may play a role in microbial transmission if they become colonized by bacteria. Patient privacy curtains are one such surface that may pose a high risk for transmission because they are high-contact surfaces, are infrequently cleaned, and healthcare workers are less likely to wash their hands after contacting inanimate objects such as curtains. To determine the amount and type of bacterial colonization of patient privacy curtains at a regional burns/plastic surgery unit. Privacy curtain contamination on the burns/plastic surgery ward was determined for two separate occasions six months apart: 23 curtains on August 2015 and 26 curtains on January 2016. Dey-Engley neutralizing agar (DENA) replicate organism detection and counting (RODAC) contact plates were used daily to sample curtains near the edge hem where they are most frequently touched. Microbial contamination was reported as cfu/cm(2) and the presence of meticillin-resistant Staphylococcus aureus (MRSA) was determined. Swabs were also taken of any open wounds and from tracheostomy sites on the ward. Curtain contamination in August 2015 was 0.7-4.7 cfu/cm(2) with 22% testing positive for MRSA, whereas contamination on January 2016 was 0.6-13.3 cfu/cm(2) with 31% of curtains testing positive for MRSA. Curtains on the burns/plastic surgery ward become colonized with significant quantities of bacteria. Future studies will need to address the rate of colonization and the clinical impact of this colonization to better inform cleaning protocols. Copyright © 2017 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  20. The effectiveness of session rating of perceived exertion to monitor resistance training load in acute burns patients.

    PubMed

    Grisbrook, Tiffany L; Gittings, Paul M; Wood, Fiona M; Edgar, Dale W

    2017-02-01

    Session-rating of perceived exertion (RPE) is a method frequently utilised in exercise and sports science to quantify training load of an entire aerobic exercise session. It has also been demonstrated that session-RPE is a valid and reliable method to quantify training load during resistance exercise, in healthy and athletic populations. This study aimed to investigate the effectiveness of session-RPE as a method to quantify exercise intensity during resistance training in patients with acute burns. Twenty burns patients (mean age=31.65 (±10.09) years), with a mean TBSA of 16.4% (range=6-40%) were recruited for this study. Patients were randomly allocated to the resistance training (n=10) or control group (n=10). All patients completed a four week resistance training programme. Training load (session-RPE×session duration), resistance training session-volume and pre-exercise pain were recorded for each exercise session. The influence of; age, gender, %TBSA, exercise group (resistance training vs. control), pre-exercise pain, resistance training history and session-volume on training load were analysed using a multilevel mixed-effects linear regression. Session-volume did not influence training load in the final regression model, however training load was significantly greater in the resistance training group, compared with the control group (p<0.001). Pre-exercise pain significantly influenced training load, where increasing pain was associated with a higher session-RPE (p=0.004). Further research is indicated to determine the exact relationship between pain, resistance training history, exercise intensity and session-RPE and training load before it can be used as a method to monitor and prescribe resistance training load in acute burns patients. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

  1. Accelerating the initial rate of hydrolysis of methyl parathion with laser excitation using monolayer protected 10 nm Au nanoparticles capped with a Cu(bpy) catalyst.

    PubMed

    Trammell, Scott A; Nita, Rafaela; Moore, Martin; Zabetakis, Dan; Chang, Eddie; Knight, D Andrew

    2012-04-28

    Using a low power green laser, we have demonstrated a rate acceleration of ~2-fold for the hydrolysis of methyl parathion by irradiating the plasmon absorption band of Au nanoparticles capped with a Cu(bpy) catalyst.

  2. Incremental slip rate and paleoseismic data from the eastern Hope fault, New Zealand: the Hossack and Green Burn sites

    NASA Astrophysics Data System (ADS)

    Hatem, A. E.; Dolan, J. F.; Langridge, R.; Zinke, R. W.; McGuire, C. P.; Rhodes, E.; Van Dissen, R. J.

    2016-12-01

    We present incremental slip rate and paleo-earthquake data from the Conway segment of the eastern Hope fault, within the Marlborough Fault System (MFS) in the northern South Island of New Zealand. Our incremental slip rate site at Hossack Station is located near the western boundary of the Conway segment (near the Hanmer pull-apart basin), and preserves four offsets of the Hossack Stream channel that range in size from c. 11 to 190 m. Channel cut and fill deposits were exposed in several fault-parallel (channel perpendicular) trenches, and the initiation and abandonment of these offset channels are constrained by >60 radiocarbon ages, yielding four incremental slip rates spanning the Holocene. Our paleoseismologic trench at Green Burn, at the eastern end of the Conway segment near Kaikoura, was excavated across the 5-m-high fault scarp into the adjacent bog deposits. This fault-perpendicular trench revealed evidence for at least four paleo-earthquakes with age constraints provided by >40 radiocarbon dates. These results add to a growing body of slip rate and paleo-earthquake age and displacement data from all four main strike-slip faults that comprise the MFS. Collectively, these observations from the Hope fault are beginning to reveal the detailed system-level behavior of the four main faults in the MFS, with fundamental implications for, among other things, earthquake occurrence and behavior, as well as seismic hazard assessment.

  3. Improving burn care and preventing burns by establishing a burn database in Ukraine.

    PubMed

    Fuzaylov, Gennadiy; Murthy, Sushila; Dunaev, Alexander; Savchyn, Vasyl; Knittel, Justin; Zabolotina, Olga; Dylewski, Maggie L; Driscoll, Daniel N

    2014-08-01

    Burns are a challenge for trauma care and a contribution to the surgical burden. The former Soviet republic of Ukraine has a foundation for burn care; however data concerning burns in Ukraine has historically been scant. The objective of this paper was to compare a new burn database to identify problems and implement improvements in burn care and prevention in this country. Retrospective analyses of demographic and clinical data of burn patients including Tukey's post hoc test, analysis of variance, and chi square analyses, and Fisher's exact test were used. Data were compared to the American Burn Association (ABA) burn repository. This study included 1752 thermally injured patients treated in 20 hospitals including Specialized Burn Unit in Municipal Hospital #8 Lviv, Lviv province in Ukraine. Scald burns were the primary etiology of burns injuries (70%) and burns were more common among children less than five years of age (34%). Length of stay, mechanical ventilation use, infection rates, and morbidity increased with greater burn size. Mortality was significantly related to burn size, inhalation injury, age, and length of stay. Wound infections were associated with burn size and older age. Compared to ABA data, Ukrainian patients had double the length of stay and a higher rate of wound infections (16% vs. 2.4%). We created one of the first burn databases from a region of the former Soviet Union in an effort to bring attention to burn injury and improve burn care. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.

  4. [Study on intestinal absorption rate of glucose electrolyte solution during enteral resuscitation of 35% total body surface area burn injury in dog].

    PubMed

    Che, Jin-wei; Hu, Sen; Du, Ying; Bao, Cheng-mei; Tian, Yi-jun; Wang, Lei; Sheng, Zhi-yong

    2008-03-01

    To investigate the intestinal absorption rate of glucose-electrolyte solution (GES) during enteral resuscitation of burn injury in Beagle dogs, and compare the effect of enteral intake with that of intravenous infusion resuscitation. Twelve male Beagle dogs were subjected to a 35% total body surface area (TBSA) full-thickness flame III degree injury. Thirty minutes after burn, each dog was given either enteral resuscitation with a GES (EGES group) or intravenous resuscitation with lactated Ringer's solution (IVLR group), and the amount and speed of replenishment of fluid were in accordance with Parkland formula. In the first 8 hours post burn, intestinal absorption rates of water and Na+ were continuously assessed using phenol red as a nonabsorbable marker for water absorption rate. The plasma volume (PV) was measured by the dye (indocyanine green) dilution technique, and the plasma concentration of Na+, mean arterial pressure (MAP) cardiac output (CO), and urine volume were also determined in the first 8 hours. All above measurement were performed in animals without anesthesia. At the end of 8-hour-period of experiment, the remnant fluids in the intestine were collected to calculate the total volume of fluid absorbed in 8 hours. The intestinal absorption rates of water and Na+ reduced markedly down to lowest level (21% and 37% of pre-injury level) at 3.5 hours post burn, and then increased slowly. But the mean absorption rate of water was similar to infusing rate according to Parkland formula [(99+/-47) mlxh(-1)xm(-1) vs. (81+/-11) mlxh(-1)xm(-1), P>0.05]. The total fluid absorbed by intestine was (94.8+/-3.7)% of the total fluid infused within 8 hours post burn. There were no significant differences in plasma concentration of Na+, MAP and CO between two groups at 8 hours post burn. The urine volume and PV at 4 hours in EGES group were lower than those in IVLR group (both P<0.05), but those indexes at 8 hours showed no significant difference between two groups

  5. Rates of initial spread of free-burning fires on the National Forests of California

    Treesearch

    C.A. Abell

    1940-01-01

    As early as 1914 Coert DuBois and his staff recognized that knowledge of the rates which fires spread was essential to sound fire control planning, strategy, and tactics, and therefore designed the fire report form so that such data might be accumulated. Although the individual fire report form has changed appreciably since that time, the supply of data has grown...

  6. Synchronizing Substrate Activation Rates in Multicomponent Reactions with Metal-Organic Framework Catalysts.

    PubMed

    Aguirre-Díaz, Lina María; Iglesias, Marta; Snejko, Natalia; Gutiérrez-Puebla, Enrique; Monge, M Ángeles

    2016-05-04

    A study on the influence of the cation coordination number, number of Lewis acid centers, concurrent existence of Lewis base sites, and structure topology on the catalytic activity of six new indium MOFs, has been carried out for multicomponent reactions (MCRs). The new indium polymeric frameworks, namely [In8 (OH)6 (popha)6 (H2 O)4 ]⋅3 H2 O (InPF-16), [In(popha)(2,2'-bipy)]⋅3 H2 O (InPF-17), [In3 (OH)3 (popha)2 (4,4'-bipy)]⋅4 H2 O (InPF-18), [In2 (popha)2 (4,4'-bipy)2 ]⋅3 H2 O (InPF-19), [In(OH)(Hpopha)]⋅0.5 (1,7-phen) (InPF-20), and [In(popha)(1,10-phen)]⋅4 H2 O (InPF-21) (InPF=indium polymeric framework, H3 popha=5-(4-carboxy-2-nitrophenoxy)isophthalic acid, phen=phenanthroline, bipy=bipyridine), have been hydrothermally obtained by using both conventional heating (CH) and microwave (MW) procedures. These indium frameworks show efficient Lewis acid behavior for the solvent-free cyanosilylation of carbonyl compounds, the one pot Passerini 3-component (P-3CR) and the Ugi 4-component (U-4CR) reactions. In addition, InPF-17 was found to be a highly reactive, recyclable, and environmentally benign catalyst, which allows the efficient synthesis of α-aminoacyl amides. The relationship between the Lewis base/acid active site and the catalytic performance is explained by the 2D seven-coordinated indium framework of the catalyst InPF-17. This study is an attempt to highlight the main structural and synthetic factors that have to be taken into account when planning a new, effective MOF-based heterogeneous catalyst for multicomponent reactions.

  7. Enclosure fire hazard analysis using relative energy release criteria. [burning rate and combustion control

    NASA Technical Reports Server (NTRS)

    Coulbert, C. D.

    1978-01-01

    A method for predicting the probable course of fire development in an enclosure is presented. This fire modeling approach uses a graphic plot of five fire development constraints, the relative energy release criteria (RERC), to bound the heat release rates in an enclosure as a function of time. The five RERC are flame spread rate, fuel surface area, ventilation, enclosure volume, and total fuel load. They may be calculated versus time based on the specified or empirical conditions describing the specific enclosure, the fuel type and load, and the ventilation. The calculation of these five criteria, using the common basis of energy release rates versus time, provides a unifying framework for the utilization of available experimental data from all phases of fire development. The plot of these criteria reveals the probable fire development envelope and indicates which fire constraint will be controlling during a criteria time period. Examples of RERC application to fire characterization and control and to hazard analysis are presented along with recommendations for the further development of the concept.

  8. Amorphous molybdenum sulfides as hydrogen evolution catalysts.

    PubMed

    Morales-Guio, Carlos G; Hu, Xile

    2014-08-19

    Providing energy for a population projected to reach 9 billion people within the middle of this century is one of the most pressing societal issues. Burning fossil fuels at a rate and scale that satisfy our near-term demand will irreversibly damage the living environment. Among the various sources of alternative and CO2-emission-free energies, the sun is the only source that is capable of providing enough energy for the whole world. Sunlight energy, however, is intermittent and requires an efficient storage mechanism. Sunlight-driven water splitting to make hydrogen is widely considered as one of the most attractive methods for solar energy storage. Water splitting needs a hydrogen evolution catalyst to accelerate the rate of hydrogen production and to lower the energy loss in this process. Precious metals such as Pt are superior catalysts, but they are too expensive and scarce for large-scale applications. In this Account, we summarize our recent research on the preparation, characterization, and application of amorphous molybdenum sulfide catalysts for the hydrogen evolution reaction. The catalysts can be synthesized by electrochemical deposition under ambient conditions from readily available and inexpensive precursors. The catalytic activity is among the highest for nonprecious catalysts. For example, at a loading of 0.2 mg/cm(2), the optimal catalyst delivers a current density of 10 mA/cm(2) at an overpotential of 160 mV. The growth mechanism of the electrochemically deposited film catalysts was revealed by an electrochemical quartz microcrystal balance study. While different electrochemical deposition methods produce films with different initial compositions, the active catalysts are the same and are identified as a "MoS(2+x)" species. The activity of the film catalysts can be further promoted by divalent Fe, Co, and Ni ions, and the origins of the promotional effects have been probed. Highly active amorphous molybdenum sulfide particles can also be prepared

  9. Five-Lumen Antibiotic-Impregnated Femoral Central Venous Catheters in Severely Burned Patients: An Investigation of Device Utility and Catheter-Related Bloodstream Infection Rates.

    PubMed

    Friedman, Bruce C; Mian, Mohammad A H; Mullins, Robert F; Hassan, Zaheed; Shaver, Joseph R; Johnston, Krystal K

    2015-01-01

    The objective of this study is to determine the catheter-related bloodstream infection (CRBSI) rate in a severely burned patient population, many of whom required prolonged use of central venous catheters (CVCs). Between January 2008 and June 2012, 151 patients underwent placement of 455 five-lumen minocycline/rifampin-impregnated CVCs. CRBSI was defined as at least one blood culture (>100,000 colonies) and one simultaneous roll-plate CVC tip culture (>15 colony forming units) positive for the same organism. Most patients had accidental burns (81.5%) with a mean TBSA of 50%. A mean of three catheters were inserted per patient (range, 1-25). CVCs were inserted in the femoral vein (91.2%), subclavian vein (5.3%), and internal jugular vein (3.3%). Mean overall catheter indwell time was 8 days (range, 0-39 days). The overall rate of CRBSI per 1000 catheter days was 11.2; patients with a TBSA >60% experienced significantly higher rates of CRBSI than patients with a TBSA ≤60% (16.2 vs 7.3, P = .01). CVCs placed through burned skin were four times more likely to be associated with CRBSI than CVCs placed through intact skin. The most common infectious organism was Acinetobacter baumannii. Deep venous thrombosis developed in eleven patients (7%). The overall rate of CRBSI was 11.2, consistent with published rates of CRBSI in burn patients. Thus, femoral placement of 5-lumen CVCs did not result in increased CRBSI rates. These data support the safety of femoral CVC placement in burn patients, contrary to the Centers for Disease Control recommendation to avoid femoral CVC insertion.

  10. [Analysis of articles published in Chinese Journal of Burns winning high citation rate during 2000-2009].

    PubMed

    Mo, Yu; Luo, Qin; Wang, Xu; Xie, Qiu-hong

    2010-06-01

    To analyze the inherent quality of articles published in our journal enjoying high citation rate, and to explore strategies on improving impact of papers. Scientific papers published in Chinese Journal of Burns from February 2000 to December 2009, with citation rate equal to or higher than 20 times were collected for classification according to their publication year, publication form, subject distribution, regional and institutional distribution, frequency of authors appeared in those published papers, frequency of winning prizes, and sources of fund (national, ministerial, or provincial). Data were processed by Microsoft Excel software. Altogether 64 scientific papers with high citation rate were published from 2000 to 2006. Original articles and expert forum accounted for 55 (86.0%). Twenty-one articles of clinical study were cited frequently, among them one was cited for 79 times. Articles dealing with subjects with popular interest or cutting-edge problems were cited frequently. Most articles winning high citation rate were originated from institutions located in Chongqing, Beijing, Shanghai, and Xi'an, etc. Those scientific papers which were instructed by specialists, with high level foundation and won prizes were cited with high frequency. The top 20 articles were mainly cited by excellent doctoral dissertations and master theses originated from 11 institutions for higher education, and source journals of Chinese Scientific and Technical Papers and Citations Database. Authors should emphasize subject planning in order to compose papers with high quality. The editorial board should make arrangements with influential specialists with related skills for their contributions based on subjects of popular interest concerning the cutting-edge problems of the specific specialty, and pay close attention to papers on clinical study and those with funding from high levels, to improve impact of the articles.

  11. Biomass Burning

    Atmospheric Science Data Center

    2015-07-27

    Projects:  Biomass Burning Definition/Description:  Biomass Burning: This data set represents the geographical and temporal distribution of total amount of biomass burned. These data may be used in general circulation models (GCMs) and ...

  12. Burn Institute

    MedlinePlus

    ... a resource to the community. Learn more The Burn Institute reaches thousands of children and adults each year through fire and burn prevention education, burn survivor support programs and the ...

  13. Light elements burning reaction rates at stellar temperatures as deduced by the Trojan Horse measurements

    NASA Astrophysics Data System (ADS)

    Lamia, L.; Spitaleri, C.; La Cognata, M.; Palmerini, S.; Puglia, S. M. R.; Sergi, M. L.

    2015-02-01

    Experimental nuclear astrophysics aims at determining the reaction rates for astrophysically relevant reactions at their Gamow energies. For charged-particle induced reactions, the access to these energies is usually hindered, in direct measurements, by the presence of the Coulomb barrier between the interacting particles or by electron screening effects, which make hard the determination of the bare-nucleus S(E)-factor of interest for astrophysical codes. The use of the Trojan Horse Method (THM) appears as one of the most suitable tools for investigating nuclear processes of interest for astrophysics. Here, in view of the recent TH measurements, the main destruction channels for deuterium (2H ), for the two lithium 6,7Li isotopes, for the 9Be and the one for the two boron 10,11B isotopes will be discussed.

  14. Light elements burning reaction rates at stellar temperatures as deduced by the Trojan Horse measurements

    SciTech Connect

    Lamia, L.; Spitaleri, C.; La Cognata, M.; Palmerini, S.; Sergi, M. L.; Puglia, S. M. R.

    2015-02-24

    Experimental nuclear astrophysics aims at determining the reaction rates for astrophysically relevant reactions at their Gamow energies. For charged-particle induced reactions, the access to these energies is usually hindered, in direct measurements, by the presence of the Coulomb barrier between the interacting particles or by electron screening effects, which make hard the determination of the bare-nucleus S(E)-factor of interest for astrophysical codes. The use of the Trojan Horse Method (THM) appears as one of the most suitable tools for investigating nuclear processes of interest for astrophysics. Here, in view of the recent TH measurements, the main destruction channels for deuterium ({sup 2}H), for the two lithium {sup 6,7}Li isotopes, for the {sup 9}Be and the one for the two boron {sup 10,11}B isotopes will be discussed.

  15. Experimental measurements of the 15O(alpha,gamma)19Ne reaction rate and the stability of thermonuclear burning on accreting neutron stars

    SciTech Connect

    Fisker, J; Tan, W; Goerres, J; Wiescher, M; Cooper, R

    2007-05-08

    Neutron stars in close binary star systems often accrete matter from their companion stars. Thermonuclear ignition of the accreted material in the atmosphere of the neutron star leads to a thermonuclear explosion which is observed as an X-ray burst occurring periodically between hours and days depending on the accretion rate. The ignition conditions are characterized by a sensitive interplay between the accretion rate of the fuel supply and its depletion rate by nuclear burning in the hot CNO cycle and the rp-process. For accretion rates close to stable burning the burst ignition therefore depends critically on the hot CNO breakout reaction {sup 15}O({alpha}, {gamma}){sup 19}Ne that regulates the flow between the hot CNO cycle and the rapid proton capture process. Until recently, the {sup 15}O({alpha}, {gamma}){sup 19}Ne reaction rate was not known experimentally and the theoretical estimates carried significant uncertainties. In this paper we perform a parameter study of the uncertainty of this reaction rate and determine the astrophysical consequences of the first measurement of this reaction rate. Our results corroborate earlier predictions and show that theoretically burning remains unstable up to accretion rates near the Eddington limit, in contrast to astronomical observations.

  16. Study of mercury oxidation by a selective catalytic reduction catalyst in a pilot-scale slipstream reactor at a utility boiler burning bituminous coal

    SciTech Connect

    Yan Cao; Bobby Chen; Jiang Wu; Hong Cui; John Smith; Chi-Kuan Chen; Paul Chu; Wei-Ping Pan

    2007-01-15

    One of the cost-effective mercury control technologies in coal-fired power plants is the enhanced oxidation of elemental mercury in selective catalytic reduction (SCR) followed by the capture of the oxidized mercury in the wet scrubber. This paper is the first in a series of two in which the validation of the SCR slipstream test and Hg speciation variation in runs with or without SCR catalysts inside the SCR slipstream reactor under special gas additions (HCl, Cl{sub 2}, SO{sub 2}, and SO{sub 3}) are presented. Tests indicate that the use of a catalyst in a SCR slipstream reactor can achieve greater than 90% NO reduction efficiency with a NH{sub 3}/NO ratio of about 1. There is no evidence to show that the reactor material affects mercury speciation. Both SCR catalysts used in this study exhibited a catalytic effect on the elemental mercury oxidation but had no apparent adsorption effect. SCR catalyst 2 seemed more sensitive to the operational temperature. The spike gas tests indicated that HCl can promote Hg{sup 0} oxidation but not Cl{sub 2}. The effect of Cl{sub 2} on mercury oxidation may be inhibited by higher concentrations of SO{sub 2}, NO, or H{sub 2}O in real flue-gas atmospheres within the typical SCR temperature range (300-350{sup o}C). SO{sub 2} seemed to inhibit mercury oxidation; however, SO{sub 3} may have some effect on the promotion of mercury oxidation in runs with or without SCR catalysts. 25 refs., 9 figs., 2 tabs.

  17. Catalyst mixtures

    DOEpatents

    Masel, Richard I.; Rosen, Brian A.

    2017-02-14

    Catalysts that include at least one catalytically active element and one helper catalyst can be used to increase the rate or lower the overpotential of chemical reactions. The helper catalyst can simultaneously act as a director molecule, suppressing undesired reactions and thus increasing selectivity toward the desired reaction. These catalysts can be useful for a variety of chemical reactions including, in particular, the electrochemical conversion of CO.sub.2 or formic acid. The catalysts can also suppress H.sub.2 evolution, permitting electrochemical cell operation at potentials below RHE. Chemical processes and devices using the catalysts are also disclosed, including processes to produce CO, OH.sup.-, HCO.sup.-, H.sub.2CO, (HCO.sub.2).sup.-, H.sub.2CO.sub.2, CH.sub.3OH, CH.sub.4, C.sub.2H.sub.4, CH.sub.3CH.sub.2OH, CH.sub.3COO.sup.-, CH.sub.3COOH, C.sub.2H.sub.6, O.sub.2, H.sub.2, (COOH).sub.2, or (COO.sup.-).sub.2, and a specific device, namely, a CO.sub.2 sensor.

  18. Burn mortality in Iraq.

    PubMed

    Qader, Ari Raheem

    2012-08-01

    Mortality rates are important outcome parameters after burn, and can serve as objective end points for quality control. Causes of death after severe burn have changed over time. In a prospective study, eight hundred and eighty-four burn patients were admitted to the Burns and Plastic surgery Hospital in Sulaimani-Kurdistan region of Iraq in 2009. Age, gender, nationality, cause of burn, extent of injury, cause of death and mortality rate were tabulated and analyzed, 338 (38.2%) were male and 546 (61.8%) were female. The highest number of cases occurred in January, with the highest short period incidence occurring in April. Out of 884 cases, 260 persons died. Burn injuries were more frequent and larger with higher mortality in females than in males. Flame was the major cause of burns. Self-inflicted burns were noted mainly in young women. A large number of burns which affect children and females, occur in the domestic setting and could have been prevented. Therefore, it is necessary to implement programs for health education relating to prevention of burn injuries focusing on the domestic setting. Copyright © 2012 Elsevier Ltd and ISBI. All rights reserved.

  19. β -decay rate of 59Fe in shell burning environment and its influence on the production of 60Fe in a massive star

    NASA Astrophysics Data System (ADS)

    Li, K. A.; Lam, Y. H.; Qi, C.; Tang, X. D.; Zhang, N. T.

    2016-12-01

    We deduced the stellar β -decay rate of 59Fe at typical carbon-shell burning temperature by taking the experimental Gamow-Teller transition strengths of the 59Fe excited states. The result is also compared with those derived from large-scale shell model calculations. The new rate is up to a factor of 2.5 lower than the theoretical rate of Fuller, Fowler, and Newman (FFN) and up to a factor of 5 higher than decay rate of Langanke and Martínez-Pinedo (LMP) in the temperature region 0.5 ≤T ≤2 GK. We estimated the impact of the newly determined rate on the synthesis of cosmic γ emitter 60Fe in C-shell burning and explosive C/Ne burning using a one-zone model calculation. Our results show that 59Fe stellar β decay plays an important role in 60Fe nucleosynthesis, even though the uncertainty of the decay rate is rather large due to the error of B (GT) strengths.

  20. Homogeneous ice nucleation from aqueous inorganic/organic particles representative of biomass burning: water activity, freezing temperatures, nucleation rates.

    PubMed

    Knopf, Daniel A; Rigg, Yannick J

    2011-02-10

    Homogeneous ice nucleation plays an important role in the formation of cirrus clouds with subsequent effects on the global radiative budget. Here we report on homogeneous ice nucleation temperatures and corresponding nucleation rate coefficients of aqueous droplets serving as surrogates of biomass burning aerosol. Micrometer-sized (NH(4))(2)SO(4)/levoglucosan droplets with mass ratios of 10:1, 1:1, 1:5, and 1:10 and aqueous multicomponent organic droplets with and without (NH(4))(2)SO(4) under typical tropospheric temperatures and relative humidities are investigated experimentally using a droplet conditioning and ice nucleation apparatus coupled to an optical microscope with image analysis. Homogeneous freezing was determined as a function of temperature and water activity, a(w), which was set at droplet preparation conditions. The ice nucleation data indicate that minor addition of (NH(4))(2)SO(4) to the aqueous organic droplets renders the temperature dependency of water activity negligible in contrast to the case of aqueous organic solution droplets. The mean homogeneous ice nucleation rate coefficient derived from 8 different aqueous droplet compositions with average diameters of ∼60 μm for temperatures as low as 195 K and a(w) of 0.82-1 is 2.18 × 10(6) cm(-3) s(-1). The experimentally derived freezing temperatures and homogeneous ice nucleation rate coefficients are in agreement with predictions of the water activity-based homogeneous ice nucleation theory when taking predictive uncertainties into account. However, the presented ice nucleation data indicate that the water activity-based homogeneous ice nucleation theory overpredicts the freezing temperatures by up to 3 K and corresponding ice nucleation rate coefficients by up to ∼2 orders of magnitude. A shift of 0.01 in a(w), which is well within the uncertainty of typical field and laboratory relative humidity measurements, brings experimental and predicted freezing temperatures and homogeneous ice

  1. Impacts of Biomass Burning on the Land Use / Land Cover Dynamics in Northern Sub-Saharan Africa and Associated Alteration of Local Emission Rates

    NASA Astrophysics Data System (ADS)

    Ellison, L.; Ichoku, C. M.

    2015-12-01

    Biomass burning is a major anthropogenic event in Northern Sub-Saharan Africa (NSSA), which contributes 15-20% of the global annual total of particulate matter emissions from fires. This burning is mostly for agricultural, grazing or hunting purposes, and thus has a great potential for driving changes in the land use and land cover distribution in that region. The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard both the Terra and Aqua spacecraft have two complimentary data products to support this research: the MOD14/MYD14 active fire products measuring fire locations and strengths, and the MCD12 land cover type product, which includes the International Geosphere Biosphere Programme (IGBP) land-cover classification system used in this analysis. More specifically, the MCD12Q1 tiled data product at 500 m was used to match against the 1 km active fire product resolution for the current analysis. Paired data between instantaneous fire measurements and the underlying land cover types for the particular year over the study period of 2003-2013 reveals a dominant burning of savanna, followed by cropland land cover type throughout the region. There are a few indications of the interchange between savanna and cropland due to burning practices. Even though the fire activity in the whole NSSA region is decreasing at a rate of 1.4%/yr during the study period, some land cover types in parts of NSSA show an increase, including local increases in sensitive land cover types such as forest and wetland, which could have serious ecological implications. The changes in the overall redistribution of biomass burning amongst the different land cover types in NSSA dictate that there is also a redistribution of biomass burning emissions. The extent of these changes will also be covered in this presentation.

  2. Carborane Burning Rate Modifiers

    DTIC Science & Technology

    1980-03-20

    octyne, 1-pentyne and 5-chloro-l-pentyne) are much smaller than those of the less electrophilic acetylenes. - The values of AHt reflect the... fluorine containing derivatives (III) and (V) were prepared by re- acting (I) and (II) with excess PF5 in hexane. Thus, 0.0032 moles of the carborane

  3. Ambiguities in the rate of oxygen formation during stellar helium burning in the 12C(α,γ) reaction

    NASA Astrophysics Data System (ADS)

    Gai, Moshe

    2013-12-01

    The rate of oxygen formation determines the C/O ratio during stellar helium burning. It is the single most important nuclear input in stellar evolution theory, including the evolution of type II and type Ia supernova. However, the low-energy cross section of the fusion of 4He +12C, denoted as the 12C(α,γ)16O reaction, still remains uncertain. I analyze and critically review the most recent measurements of complete angular distributions of the outgoing γ rays at very low energies (Ec.m.≥1.0 MeV). My analysis of the angular distributions measured with the EUROGAM/GANDI arrays leads to considerably larger error bars than have been published, which excludes them from the current sample of “world data.” I show that the current sample of “world data” of the measured E2 cross-section factors below 1.7 MeV cluster into two distinct groups that lead to two distinct extrapolations: SE2(300)≈60 or SE2(300)≈154 keVb. There is a discrepancy between the measured E1-E2 phase difference (ϕ12) and unitarity as required by the Watson theorem, which suggests systematic problem(s) in some of the measured γ-ray angular distributions. The ambiguity of the extrapolated SE2(300) together with the previously observed ambiguity of SE1(300) (approximately 80 or 10 keVb) must be resolved by future measurements of complete and detailed angular distributions of the 12C(α,γ) reaction at very low energies (Ec.m.≤1.0 MeV).

  4. Regional Changes in Charcoal-Burning Suicide Rates in East/Southeast Asia from 1995 to 2011: A Time Trend Analysis

    PubMed Central

    Chang, Shu-Sen; Chen, Ying-Yeh; Yip, Paul S. F.; Lee, Won Jin; Hagihara, Akihito; Gunnell, David

    2014-01-01

    Background Suicides by carbon monoxide poisoning resulting from burning barbecue charcoal reached epidemic levels in Hong Kong and Taiwan within 5 y of the first reported cases in the early 2000s. The objectives of this analysis were to investigate (i) time trends and regional patterns of charcoal-burning suicide throughout East/Southeast Asia during the time period 1995–2011 and (ii) whether any rises in use of this method were associated with increases in overall suicide rates. Sex- and age-specific trends over time were also examined to identify the demographic groups showing the greatest increases in charcoal-burning suicide rates across different countries. Methods and Findings We used data on suicides by gases other than domestic gas for Hong Kong, Japan, the Republic of Korea, Taiwan, and Singapore in the years 1995/1996–2011. Similar data for Malaysia, the Philippines, and Thailand were also extracted but were incomplete. Graphical and joinpoint regression analyses were used to examine time trends in suicide, and negative binomial regression analysis to study sex- and age-specific patterns. In 1995/1996, charcoal-burning suicides accounted for <1% of all suicides in all study countries, except in Japan (5%), but they increased to account for 13%, 24%, 10%, 7%, and 5% of all suicides in Hong Kong, Taiwan, Japan, the Republic of Korea, and Singapore, respectively, in 2011. Rises were first seen in Hong Kong after 1998 (95% CI 1997–1999), followed by Singapore in 1999 (95% CI 1998–2001), Taiwan in 2000 (95% CI 1999–2001), Japan in 2002 (95% CI 1999–2003), and the Republic of Korea in 2007 (95% CI 2006–2008). No marked increases were seen in Malaysia, the Philippines, or Thailand. There was some evidence that charcoal-burning suicides were associated with an increase in overall suicide rates in Hong Kong, Taiwan, and Japan (for females), but not in Japan (for males), the Republic of Korea, and Singapore. Rates of change in charcoal-burning suicide

  5. Regional changes in charcoal-burning suicide rates in East/Southeast Asia from 1995 to 2011: a time trend analysis.

    PubMed

    Chang, Shu-Sen; Chen, Ying-Yeh; Yip, Paul S F; Lee, Won Jin; Hagihara, Akihito; Gunnell, David

    2014-04-01

    Suicides by carbon monoxide poisoning resulting from burning barbecue charcoal reached epidemic levels in Hong Kong and Taiwan within 5 y of the first reported cases in the early 2000s. The objectives of this analysis were to investigate (i) time trends and regional patterns of charcoal-burning suicide throughout East/Southeast Asia during the time period 1995-2011 and (ii) whether any rises in use of this method were associated with increases in overall suicide rates. Sex- and age-specific trends over time were also examined to identify the demographic groups showing the greatest increases in charcoal-burning suicide rates across different countries. We used data on suicides by gases other than domestic gas for Hong Kong, Japan, the Republic of Korea, Taiwan, and Singapore in the years 1995/1996-2011. Similar data for Malaysia, the Philippines, and Thailand were also extracted but were incomplete. Graphical and joinpoint regression analyses were used to examine time trends in suicide, and negative binomial regression analysis to study sex- and age-specific patterns. In 1995/1996, charcoal-burning suicides accounted for <1% of all suicides in all study countries, except in Japan (5%), but they increased to account for 13%, 24%, 10%, 7%, and 5% of all suicides in Hong Kong, Taiwan, Japan, the Republic of Korea, and Singapore, respectively, in 2011. Rises were first seen in Hong Kong after 1998 (95% CI 1997-1999), followed by Singapore in 1999 (95% CI 1998-2001), Taiwan in 2000 (95% CI 1999-2001), Japan in 2002 (95% CI 1999-2003), and the Republic of Korea in 2007 (95% CI 2006-2008). No marked increases were seen in Malaysia, the Philippines, or Thailand. There was some evidence that charcoal-burning suicides were associated with an increase in overall suicide rates in Hong Kong, Taiwan, and Japan (for females), but not in Japan (for males), the Republic of Korea, and Singapore. Rates of change in charcoal-burning suicide rate did not differ by sex/age group in

  6. The role of a dipeptide outer-coordination sphere on H2-production catalysts: influence on catalytic rates and electron transfer.

    PubMed

    Reback, Matthew L; Ginovska-Pangovska, Bojana; Ho, Ming-Hsun; Jain, Avijita; Squier, Thomas C; Raugei, Simone; Roberts, John A S; Shaw, Wendy J

    2013-02-04

    The outer-coordination sphere of enzymes acts to fine-tune the active site reactivity and control catalytic rates, suggesting that incorporation of analogous structural elements into molecular catalysts may be necessary to achieve rates comparable to those observed in enzyme systems at low overpotentials. In this work, we evaluate the effect of an amino acid and dipeptide outer-coordination sphere on [Ni(P(Ph)(2)N(Ph-R)(2))(2)](2+) hydrogen production catalysts. A series of 12 new complexes containing non-natural amino acids or dipeptides was prepared to test the effects of positioning, size, polarity and aromaticity on catalytic activity. The non-natural amino acid was either 3-(meta- or para-aminophenyl)propionic acid terminated as an acid, an ester or an amide. Dipeptides consisted of one of the non-natural amino acids coupled to one of four amino acid esters: alanine, serine, phenylalanine or tyrosine. All of the catalysts are active for hydrogen production, with rates averaging ∼1000 s(-1), 40 % faster than the unmodified catalyst. Structure and polarity of the aliphatic or aromatic side chains of the C-terminal peptide do not strongly influence rates. However, the presence of an amide bond increases rates, suggesting a role for the amide in assisting catalysis. Overpotentials were lower with substituents at the N-phenyl meta position. This is consistent with slower electron transfer in the less compact, para-substituted complexes, as shown in digital simulations of catalyst cyclic voltammograms and computational modeling of the complexes. Combining the current results with insights from previous results, we propose a mechanism for the role of the amino acid and dipeptide based outer-coordination sphere in molecular hydrogen production catalysts.

  7. The Role of a Dipeptide Outer-Coordination Sphere on H2 -Production Catalysts: Influence on Catalytic Rates and Electron Transfer

    SciTech Connect

    Reback, Matthew L.; Ginovska-Pangovska, Bojana; Ho, Ming-Hsun; Jain, Avijita; Squier, Thomas C.; Raugei, Simone; Roberts, John A.; Shaw, Wendy J.

    2013-02-04

    The outer-coordination sphere of enzymes acts to fine-tune the active site reactivity and control catalytic rates, suggesting that incorporation of analogous structural elements into molecular catalysts may be necessary to achieve rates comparable to those observed in enzyme systems at low overpotentials. In this work, we evaluate the effect of an amino acid and dipeptide outer-coordination sphere on [Ni(PPh2NPh-R2)2]2+ hydrogen production catalysts. A series of 12 new complexes containing non-natural amino acids or dipeptides were prepared to test the effects of positioning, size, polarity and aromaticity on catalytic activity. The non-natural amino acid was either 3-(meta- or para-aminophenyl)propionic acid terminated as an acid, an ester or an amide. Dipeptides consisted of one of the non-natural amino acids coupled to one of four amino acid esters: alanine, serine, phenylalanine or tyrosine. All of the catalysts are active for hydrogen production, with rates averaging ~1000 s-1, 40% faster than the unmodified catalyst. Structure and polarity of the aliphatic or aromatic side chains of the C-terminal peptide do not strongly influence rates. However, the presence of an amide bond increases rates, suggesting a role for the amide in assisting catalysis. Overpotentials were lower with substituents at the N-phenyl meta position. This is consistent with slower electron transfer in the less compact, para-substituted complexes, as shown in digital simulations of catalyst cyclic voltammograms and computational modeling of the complexes. Combining the current results with insights from previous results, we propose a mechanism for the role of the amino acid and dipeptide based outer-coordination sphere in molecular hydrogen production catalysts.

  8. Reduced Uncertainties in the Supernova Production of the Gamma Emitting Nuclei 26Al, 44Ti, and 60Fe Using Effective Helium Burning Rates

    NASA Astrophysics Data System (ADS)

    Austin, Sam M.; West, Christopher; Heger, Alexander

    2016-09-01

    Uncertainties in the helium burning reaction rates caused large uncertainties in previous predictions of the production of the gamma emitting nuclei 26Al and (especially) 60Fe in core collapse supernovae. This precluded a meaningful comparison of the predictions with observed gamma ray intensities. We present results using a newly developed effective reaction rate (ERR) for the helium burning reactions to predict the yields of 26Al, 44Ti, and 60Fe. The resulting yield uncertainties using the ERR are much smaller than obtained previously, and smaller than other uncertainties. The yield ratio, 60Fe/26Al, had variations of less than 20 percent and appears to be the most robust observable related to the production of these nuclei. We also estimated the effects of failed supernovae on the yields by using a compactness filter. This substantially reduced the three yields but the ratio, 60Fe/26Al, was little affected. Research supported by US NSF and DOE, and by ARC.

  9. Cooking-related pediatric burns: risk factors and the role of differential cooling rates among commonly implicated substances.

    PubMed

    Dissanaike, Sharmila; Boshart, Kimberly; Coleman, Alan; Wishnew, Jenna; Hester, Cynthia

    2009-01-01

    Cooking-related injuries are a common problem worldwide, resulting in more pediatric burns than any other cause. We identified risk factors-associated mechanisms and determined cooling curves for common substances. A retrospective review of children admitted to a Level I burn center between 2001 and 2006 was performed. Variables including injury mechanism, age, sex, race, burn area, length of stay, and outcome were recorded. Commonly implicated substances were identified, and cooling curves for each were measured at room temperature. Logistic regression analysis was performed to identify risk factors for cooking injury. A total of 541 pediatric burn patients were admitted, of whom 123 had cooking-related injuries. Common substances involved included soup (27%), grease (26%), coffee (18%), beans (9%), and menudo (2.3%), a traditional Mexican soup based on tripe, hominy, and chile. Children with cooking injuries were significantly younger than other groups, with a mean age of 2.7 years. The most common mechanism was the child pulling the substance down from a height, accounting for nearly half of all injuries. This resulted in a characteristic scald pattern involving a wide area across chest and shoulders narrowing to a point near the pelvis. The average burn area was 7%, associated with a hospital stay of 4 days and mortality below 1%. Analysis of cooling curves revealed surprising variation in heat retention, with semisolid or high-density liquids posing a markedly increased burn risk. Cooking injuries predominantly affect toddlers, with clearly recognized mechanisms and risk factors. Injury prevention measures should be targeted accordingly.

  10. Photodegradation of 4-chlorophenoxyacetic acid under visible LED activated N-doped TiO2 and the mechanism of stepwise rate increment of the reused catalyst.

    PubMed

    Abdelhaleem, Amal; Chu, Wei

    2017-09-15

    Photodegradation of 4-chlorophenoxyacetic acid (4-CPA) was systematically investigated using N-doped TiO2 (N-TiO2) under commercially available visible light emitting diode (Vis LED) as a novel Vis LED illumination in photocatalysis applications. The synergetic effect of Vis LED/N-TiO2 process was studied in detail by varying reaction conditions including the initial concentration of 4-CPA, catalyst dosage, light intensity, and initial pH. Additionally, the influence of inorganic anions and radical scavengers on the performance of the Vis LED/N-TiO2 process was also evaluated. The Vis LED/N-TiO2 was found to be a promising process in terms of mineralization of 4-CPA. It is interesting to note that the performance of this process was not reduced after successive usage of the recycled catalyst; instead, the reaction rate of 4-CPA decay actually increased by using the spent catalyst. The mechanism behind rate enhancement after/during reuse was explored by XPS and FT-IR analyses and it was proven that hydroxyl groups can be incorporated into the catalyst surface by the repeated wetting of N-TiO2 after each reuse. This facilitates the formation of hydrogen bonds between the 4-CPA molecules and N-TiO2, thereby allowing more collisions between the trapped 4-CPA and radicals at the interface of bulk solution and catalyst, respectively. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Effects of magnesium-based hydrogen storage materials on the thermal decomposition, burning rate, and explosive heat of ammonium perchlorate-based composite solid propellant.

    PubMed

    Liu, Leili; Li, Jie; Zhang, Lingyao; Tian, Siyu

    2017-08-24

    MgH2, Mg2NiH4, and Mg2CuH3 were prepared, and their structure and hydrogen storage properties were determined through X-ray photoelectron spectroscopy and thermal analyzer. The effects of MgH2, Mg2NiH4, and Mg2CuH3 on the thermal decomposition, burning rate, and explosive heat of ammonium perchlorate-based composite solid propellant were subsequently studied. Results indicated that MgH2, Mg2NiH4, and Mg2CuH3 can decrease the thermal decomposition peak temperature and increase the total released heat of decomposition. These compounds can improve the effect of thermal decomposition of the propellant. The burning rates of the propellant increased using Mg-based hydrogen storage materials as promoter. The burning rates of the propellant also increased using MgH2 instead of Al in the propellant, but its explosive heat was not enlarged. Nonetheless, the combustion heat of MgH2 was higher than that of Al. A possible mechanism was thus proposed. Copyright © 2017. Published by Elsevier B.V.

  12. On-line regeneration of hydrodesulfurization catalyst

    DOEpatents

    Preston, Jr., John L.

    1980-01-01

    A hydrotreating catalyst is regenerated as it concurrently hydrotreats a hydrocarbon fuel by introducing a low concentration of oxygen into the catalyst bed either continuously or periodically. At low oxygen concentrations the carbon deposits on the catalyst are burned off without harming the catalyst and without significantly affecting the hydrotreating process. In a preferred embodiment the hydrotreating process is hydrodesulfurization, and regenerating is done periodically with oxygen concentrations between 0.1 and 0.5 volume percent.

  13. Four-man rated dual catalyst system for the recovery of water from urine

    NASA Technical Reports Server (NTRS)

    Budininkas, P.

    1978-01-01

    The catalytic system was integrated with a 4-man rated urine wick evaporator. During operation, urine vapor produced by the wick-evaporator was treated in the catalytic system to remove ammonia and volatile hydrocarbons, and water was recovered by condensation in a water cooled condenser. The system operated completely automatically and required no manual adjustments, except periodic supply of urine and removal of the recovered water. Although the system was designed for treating 0.325 kg urine per hour, this rate could be achieved only with a fresh wick, then gradually decreased as the wick became saturated with urine solids. The average urine treatment rates achieved during each of the three endurance tests were 0.137, 0.217, and 0.235 kg/hr. The quality of the recovered water meets drinking water standards, with the exception of a generally low pH.

  14. Mathematical model of reaction rate oscillations on a chain of nm-sized catalyst particles

    NASA Astrophysics Data System (ADS)

    Peskov, N. V.; Slinko, M. M.; Jaeger, N. I.

    2003-05-01

    The model of reaction rate oscillations over the surface of nanoparticles embedded into zeolite matrix is numerically investigated. The reaction rate oscillations on each particle are described by a lumped model. The reactions on separate particles interact via the gas diffusion through the pores, which is modeled in the frame of the Maxwell-Stefan approach. The reaction reveals a complex dynamical behavior if a nonhomogeneous distribution of reagent concentrations exists along the chain of particles with a sufficiently large gradient near the ends of the chain.

  15. Evaluation of nurse accuracy in rating procedural pain among pediatric burn patients using the Face, Legs, Activity, Cry, Consolability (FLACC) Scale.

    PubMed

    Shen, Jiabin; Giles, Sheila A; Kurtovic, Kelli; Fabia, Renata; Besner, Gail E; Wheeler, Krista K; Xiang, Huiyun; Groner, Jonathan I

    2017-02-01

    Accurate pain assessment is essential for proper analgesia during medical procedures in pediatric patients. The Faces, Legs, Activity, Cry, and Consolability (FLACC) scale has previously been shown to be a valid and reliable tool for assessing pediatric procedural pain in research labs. However, no study has investigated how rater factors (gender, number of dressing changes performed/week, burn history, having children, nursing experience, stress at home/work) and patient factors (pain intensity) affect the accuracy of FLACC ratings for procedural pain when implemented by bedside care providers. Twenty-four nurses in an ABA verified Pediatric Burn Center watched four videos of dressing changes for pediatric burn patients in random order three times and rated the children's procedural pain using the FLACC scale. The four videos had standard FLACC scores established by an interdisciplinary panel. Descriptive and mixed modeling analysis was conducted to explore nurse rating accuracy and to evaluate the rater and patient factors that influenced the rating accuracy. The highest accuracy was reached when rating high procedural pain (with a FLACC of 6). Nurses underrated both mild and severe procedural pain. Nurses who had less nursing experience demonstrated significantly higher accuracy than those with more experience. The present study is the first study in the literature to systematically examine the factors influencing the accuracy of FLACC rating for pediatric procedural pain among bedside care providers. The findings suggest that nurse clinical experience and patient pain intensity are two significant contributors to rating accuracy. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

  16. Disilane as a growth rate catalyst of plasma deposited microcrystalline silicon thin films

    NASA Astrophysics Data System (ADS)

    Dimitrakellis, P.; Kalampounias, A. G.; Spiliopoulos, N.; Amanatides, E.; Mataras, D.; Lahootun, V.; Coeuret, F.; Madec, A.

    2016-07-01

    The effect of small disilane addition on the gas phase properties of silane-hydrogen plasmas and the microcrystalline silicon thin films growth is presented. The investigation was conducted in the high pressure regime and for constant power dissipation in the discharge with the support of plasma diagnostics, thin film studies and calculations of discharge microscopic parameters and gas dissociation rates. The experimental data and the calculations show a strong effect of disilane on the electrical properties of the discharge in the pressure window from 2 to 3 Torr that is followed by significant raise of the electron number density and the drop of the sheaths electric field intensity. Deposition rate measurements show an important four to six times increase even for disilane mole fractions as low as 0.3 %. The deposition rate enhancement was followed by a drop of the material crystalline volume fraction but films with crystallinity above 40 % were deposited with different combinations of total gas pressure, disilane and silane molar ratios. The enhancement was partly explained by the increase of the electron impact dissociation rate of silane which rises by 40% even for 0.1% disilane mole fraction. The calculations of the gas usage, the dissociation and the deposition efficiencies show that the beneficial effect on the growth rate is not just the result of the increase of Si-containing molecules density but significant changes on the species participating to the deposition and the mechanism of the film growth are caused by the disilane addition. The enhanced participation of the highly sticking to the surface radical such as disilylene, which is the main product of disilane dissociation, was considered as the most probable reason for the significant raise of the deposition efficiency. The catalytic effect of such type of radical on the surface reactivity of species with lower sticking probability is further discussed, while it is also used to explain the restricted

  17. Disilane as a growth rate catalyst of plasma deposited microcrystalline silicon thin films

    SciTech Connect

    Dimitrakellis, P.; Amanatides, E. Mataras, D.; Kalampounias, A. G.; Spiliopoulos, N.; Lahootun, V.; Coeuret, F.; Madec, A.

    2016-07-15

    The effect of small disilane addition on the gas phase properties of silane-hydrogen plasmas and the microcrystalline silicon thin films growth is presented. The investigation was conducted in the high pressure regime and for constant power dissipation in the discharge with the support of plasma diagnostics, thin film studies and calculations of discharge microscopic parameters and gas dissociation rates. The experimental data and the calculations show a strong effect of disilane on the electrical properties of the discharge in the pressure window from 2 to 3 Torr that is followed by significant raise of the electron number density and the drop of the sheaths electric field intensity. Deposition rate measurements show an important four to six times increase even for disilane mole fractions as low as 0.3 %. The deposition rate enhancement was followed by a drop of the material crystalline volume fraction but films with crystallinity above 40 % were deposited with different combinations of total gas pressure, disilane and silane molar ratios. The enhancement was partly explained by the increase of the electron impact dissociation rate of silane which rises by 40% even for 0.1% disilane mole fraction. The calculations of the gas usage, the dissociation and the deposition efficiencies show that the beneficial effect on the growth rate is not just the result of the increase of Si-containing molecules density but significant changes on the species participating to the deposition and the mechanism of the film growth are caused by the disilane addition. The enhanced participation of the highly sticking to the surface radical such as disilylene, which is the main product of disilane dissociation, was considered as the most probable reason for the significant raise of the deposition efficiency. The catalytic effect of such type of radical on the surface reactivity of species with lower sticking probability is further discussed, while it is also used to explain the restricted

  18. Burn Wise

    EPA Pesticide Factsheets

    Burn Wise is a partnership program of the U.S. Environmental Protection Agency that emphasizes the importance of burning the right wood, the right way, in the right appliance to protect your home, health, and the air we breathe.

  19. Burns (image)

    MedlinePlus

    ... degree burns damage the outer layer of skin (epidermis) and cause pain, redness and swelling (erythema). Second degree burns damage the epidermis and the inner layer, the dermis, causing erythema ...

  20. The combustion of large particles of char in bubbling fluidized beds: The dependence of Sherwood number and the rate of burning on particle diameter

    SciTech Connect

    Dennis, J.S.; Hayhurst, A.N.; Scott, S.A.

    2006-11-15

    Particles of char derived from a variety of fuels (e.g., biomass, sewage sludge, coal, or graphite), with diameters in excess of {approx}1.5mm, burn in fluidized bed combustors containing smaller particles of, e.g., sand, such that the rate is controlled by the diffusion both of O{sub 2} to the burning solid and of the products CO and CO{sub 2} away from it into the particulate phase. It is therefore important to characterize these mass transfer processes accurately. Measurements of the burning rate of char particles made from sewage sludge suggest that the Sherwood number, Sh, increases linearly with the diameter of the fuel particle, d{sub char} (for d{sub char}>{approx}1.5mm). This linear dependence of Sh on d{sub char} is expected from the basic equation Sh=2{epsilon}{sub mf}(1+d{sub char}/2{delta}{sub diff})/{tau}, provided the thickness of the boundary layer for mass transfer, {delta}{sub diff}, is constant in the region of interest (d{sub char}>{approx}1.5mm). Such a dependence is not seen in the empirical equations currently used and based on the Frossling expression. It is found here that for chars made from sewage sludge (for d{sub char}>{approx}1.5mm), the thickness of the boundary layer for mass transfer in a fluidized bed, {delta}{sub diff}, is less than that predicted by empirical correlations based on the Frossling expression. In fact, {delta}{sub diff} is not more than the diameter of the fluidized sand particles. Finally, the experiments in this study indicate that models based on surface renewal theory should be rejected for a fluidized bed, because they give unrealistically short contact times for packets of fluidized particles at the surface of a burning sphere. The result is the new correlation Sh = 2{epsilon}{sub mf}/{tau} + (A{sub cush}/A{sub char})(d{sub char}/ {delta}{sub diff}) for the dependence of Sh on d{sub char}, the diameter of a burning char particle. This equation is based on there being a gas-cushion of fluidizing gas underneath a

  1. An Examination of Binder Systems and Their Influences on Burn Rates of High-Nitrogen Containing Formulations

    DTIC Science & Technology

    2011-01-01

    Defense spends tens of billions of dollars annually on per- chlorate remediation efforts. Therefore, efforts to elimi- nate perchlorate from military...develop per- chlorate -free formulations of the M126A1 red star para- chute. To maximize the performance of these formula- tions, KClO4 was replaced...replacement (Table 3). As detailed in Table 4, the burn time of the per- chlorate -containing baseline outperformed all Laminac 4116/Lupersol-based

  2. High repetition rate sealed CO2 TEA lasers using heterogeneous catalysts

    NASA Technical Reports Server (NTRS)

    Price, H. T.; Shaw, S. R.

    1987-01-01

    The significant operational advantages offered by CO2 lasers, operating in the 10.6 micron region of the spectrum, over current solid state lasers, emitting in the near IR region, have prompted increased interest in the development of compact, reliable, rugged CO2 laser sources. Perhaps the most critical aspect associated with achieving a laser compatible with military use is the development of lasers which require no gas replenishment. Sealed, single shot, CO2 TEA lasers have been available for a number of years. Stark et al were first to demonstrate reliable sealed operation in single shot CO2 TEA lasers in 1975 using gas catalysis. GEC Avionics reported the compact, environmentally qualified, MKIII CO2 TEA laser with a pulse life of greater than 10 to the 6th power pulses in 1980. A sealed laser lifetime of greater than 10 to the 6th power pulses is acceptable for single shot cases, such as direct detection rangefinders for tank laser sights. However, in many other applications, such as tracking of fast moving targets, it is essential that a repetition rate of typically 30Hz to 100Hz is employed. In such cases, a pulse lifetime of 10 to the 6th power pulses is no longer sufficient and a minimum pulse lifetime 10 to the 7th power pulses is essential to ensure a useful service life. In 1983 Stark el al described a sealed, 100Hz CO2 TEA laser, with a life of greater than 2.6 x 10 to the 6th power, which employed heterogeneous catalysis. Following this pioneering work, GEC Avionics has been engaged in the development of sealed high repetition rate lasers with a pulse lifetime of 20 million pulses.

  3. The Influence of Fuel Moisture, Charge Size, Burning Rate and Air Ventilation Conditions on Emissions of PM, OC, EC, Parent PAHs, and Their Derivatives from Residential Wood Combustion

    PubMed Central

    Shen, Guofeng; Xue, Miao; Wei, Siye; Chen, Yuanchen; Wang, Bin; Wang, Rong; Lv, Yan; Shen, Huizhong; Li, Wei; Zhang, Yanyan; Huang, Ye; Chen, Han; Wei, Wen; Zhao, Qiuyue; Li, Bin; Wu, Haisuo; TAO, Shu

    2014-01-01

    Controlled combustion experiments were conducted to investigate the influence of fuel charge size, moisture, air ventilation and burning rate on the emission factors (EFs) of carbonaceous particulate matter, parent polycyclic aromatic hydrocarbons (pPAHs) and their derivatives from residential wood combustion in a typical brick cooking stove. Measured EFs were found to be independent of fuel charge size, but increased with increasing fuel moisture. Pollution emissions from a normal burning under an adequate air supply condition were the lowest for most pollutants, while more pollutants were emitted when the oxygen deficient atmosphere was formed in stove chamber during fast burning. The impact of these 4 factors on particulate matter size distribution was also studied. Modified combustion efficiency and the four investigated factors explained 68, 72, and 64% of total variations in EFs of PM, organic carbon, and oxygenated PAHs, respectively, but only 36, 38 and 42% of the total variations in EFs of elemental carbon, pPAHs and nitro-PAHs, respectively. PMID:24520723

  4. Nutrition of burned patients.

    PubMed

    Gudaviciene, Daiva; Rimdeika, Rytis; Adamonis, Kestutis

    2004-01-01

    Burns form 5-12% of all traumas. About 2,200 of patients are annually hospitalized in Lithuania. In most cases people of the employable age get burned. The treatment is often long-lasting, and afterwards recovered patients often have invalidity from burn sequels. The mortality of hospitalized burned patients is about 10%. The most common causes of death are pulmonary edema, pneumonia, sepsis and multiorgan failure. All these complications are related with insufficient nutrition. These complications are extremely frequent and dangerous for patients with more than 20% of body burned. The nutritional support of burned patient gives a possibility to increase the survival probability, to decrease complication rate and hospitalization time. Currently in Lithuania there are no standards for burned patient nutrition. More attention is given to strategy of surgical strategy and techniques, as well as antibiotic therapy. This article is the review of the different aspects of artificial nutrition of burned patient: indications, modes of nutrition, mixtures and terms of nutritional support.

  5. Burn sepsis and burn toxin

    PubMed Central

    Allgöwer, Martin; Städtler, Karl; Schoenenberger, Guido A

    1974-01-01

    The salient steps of a 20-year programme of research into the nature of burn disease are described. By burn disease we mean the late mortality and morbidity following burns. We have isolated a burn toxin which is derived from a thermal polymerization of cell membrane lipoproteins within the dermis and have studied its influence on the effects of sepsis. We have also used it in the development of active and passive immunization therapy of severe burns. ImagesFig. 2Fig. 5Fig. 6Fig. 7Fig. 8Fig. 9 PMID:4429330

  6. Burn rates of TiH2/KClO4/Viton and output testing of NASA SKD26100098-301 pressure cartridges

    NASA Technical Reports Server (NTRS)

    Holy, John A.

    1993-01-01

    The burn rates of the pyrotechnic TiH2/KClO4/Viton with a mass ratio of 30/65/5 have been measured as a function of pressure in nitrogen up to 312 MPa(45 Kpsi). The burn rates were fit to R = a pn, with a = 2.055 cm/sec/MPan and n = 0.472 between 0.15 MPa (22 psi) and 21.6 MPa (3.13 Kpsi) and a = 4.38 cm/sec/MPan and n = 0.266 between 70 MPa (10.15 Kpsi) and 312 MPa (45.25 Kpsi). The decrease in slope at the higher pressures is attributed to a diffusion limited reaction. No acoustically driven flame instabilities or large conductive-to-convective burn transitions were observed. Solid reaction products were analyzed by x-ray diffraction and scanning electron microscopy (SEM). X-ray diffraction detected only TiO2 and KC1. SEM showed that the particle size of the reaction products increased as the nitrogen pressure increased. There were no anomalous characteristics of the burn of this pyrotechnic that could be interpreted as a cause of the o-ring blow-by problem in the forward shear bolt assembly. Three NASA SKD26100098-301 pressure cartridges were fired into a fixed volume vessel that was sealed with an O-ring. A maximum pressure of 181.7 MPa(26,350 psi) was reached in around 100 ,mu sec for two shots fired into a volume of 16.3 cm3(0.996 in3). A maximum pressure of 33,460 psi was reached for one shot fired into a volume of 9.55 cm3(0.583 in3). The O-ring burned through on one shot in the larger volume and leaked on the other two thereby simulating the effects of an O-ring leak. The results imply that the piston in the shear bolt assembly would receive a large impulse even if there was a leak in an O-ring seal.

  7. Chemical burns

    PubMed Central

    Cartotto, Robert C.; Peters, Walter J.; Neligan, Peter C.; Douglas, Leith G.; Beeston, Jeff

    1996-01-01

    Objectives To report a burn unit’s experience with chemical burns and to discuss the fundamental principles in managing chemical burns. Design A chart review. Setting A burn centre at a major university-affiliated hospital. Patients Twenty-four patients with chemical burns, representing 2.6% of all burn admissions over an 8-year period at the Ross Tilley Regional Adult Burn Centre. Seventy-five percent of the burn injuries were work-related accidents. Chemicals involved included hydrofluoric acid, sulfuric acid, black liquor, various lyes, potassium permanganate and phenol. Results Fourteen patients required excision and skin grafting. Complications were frequent and included ocular chemical contacts, wound infections, tendon exposures, toe amputation and systemic reactions from absorption of chemical. One patient died from a chemical scald burn to 98% of the body surface area. Conclusions The key principles in the management of chemical burns include removal of the chemical, copious irrigation, limited use of antidotes, correct estimation of the extent of injury, identification of systemic toxicity, treatment of ocular contacts and management of chemical inhalation injury. Individualized treatment is emphasized. PMID:8640619

  8. Cement Burns

    PubMed Central

    Alam, Munir; Moynagh, M.; Lawlor, C.

    2007-01-01

    Objective: Cement burns account for relatively few admissions to a burn unit; however, these burns deserve separate consideration because of special features of diagnosis and management. Cement burns, even though potentially disabling, have rarely been reported in literature. Methods: A retrospective review was performed of all patients admitted with cement burns injuries to the national burns unit at the St James's Hospital in Dublin, Ireland, over a 10-year period for the years 1996–2005. Results: A total of 46 patients with cement burns were admitted. The majority of patients were aged 16–74 years (mean age = 32 years). Eighty-seven percent of injuries occurred in an industrial and 13% in a domestic setting. The upper and lower extremities were involved in all the patients, and the mean total body surface area affected was 6.5%. The mean length of hospital stay was 21 days with a range of 1–40 days. Thirty-eight (82%) were surgically managed involving debridement and split-thickness skin graft (SSG) and four (9%) were conservatively managed. A further four did not have data available. Conclusion: Widespread inexperience in dealing with this group of cement burns patients and delays in referral to burns unit highlights the potential for greater levels of general awareness and knowledge in both prevention and treatment of these burns. As well, early debridement and split-thickness skin grafting at diagnosis constitutes the best means of reducing the high socioeconomic costs and allows for early return to work. PMID:18091981

  9. The β-decay rates of 59Fe isotopes in shell burning environments and their influences on the production of 60Fe in massive star

    NASA Astrophysics Data System (ADS)

    Li, K.; Lam, Y. H.; Qi, C.; Tang, X.; Zhang, N.

    2016-02-01

    The experimental B(GT) strengths of the 59Fe excited states were employed to determine the transition strengths which greatly contribute 59Fe stellar β-decay at typical carbon shell burning temperature. The result has been compared with the theoretical rates FFN (Fuller-Fowler-Newman) and LMP (Langanke&Martinez-Pinedo). Impact of the newly determined rate on the synthesis of cosmic γ emitter 60Fe has also been studied using one-zone model calculation. Our results show 59Fe stellar β-decay rate plays an important role in the 60Fe nucleosynthesis. However the uncertainty of the decay rate is rather large due to the error of B(GT) strength that requires further studies.

  10. Are High-Severity Fires Burning at Much Higher Rates Recently than Historically in Dry-Forest Landscapes of the Western USA?

    PubMed Central

    Baker, William L.

    2015-01-01

    Dry forests at low elevations in temperate-zone mountains are commonly hypothesized to be at risk of exceptional rates of severe fire from climatic change and land-use effects. Their setting is fire-prone, they have been altered by land-uses, and fire severity may be increasing. However, where fires were excluded, increased fire could also be hypothesized as restorative of historical fire. These competing hypotheses are not well tested, as reference data prior to widespread land-use expansion were insufficient. Moreover, fire-climate projections were lacking for these forests. Here, I used new reference data and records of high-severity fire from 1984–2012 across all dry forests (25.5 million ha) of the western USA to test these hypotheses. I also approximated projected effects of climatic change on high-severity fire in dry forests by applying existing projections. This analysis showed the rate of recent high-severity fire in dry forests is within the range of historical rates, or is too low, overall across dry forests and individually in 42 of 43 analysis regions. Significant upward trends were lacking overall from 1984–2012 for area burned and fraction burned at high severity. Upward trends in area burned at high severity were found in only 4 of 43 analysis regions. Projections for A.D. 2046–2065 showed high-severity fire would generally be still operating at, or have been restored to historical rates, although high projections suggest high-severity fire rotations that are too short could ensue in 6 of 43 regions. Programs to generally reduce fire severity in dry forests are not supported and have significant adverse ecological impacts, including reducing habitat for native species dependent on early-successional burned patches and decreasing landscape heterogeneity that confers resilience to climatic change. Some adverse ecological effects of high-severity fires are concerns. Managers and communities can improve our ability to live with high-severity fire

  11. Are High-Severity Fires Burning at Much Higher Rates Recently than Historically in Dry-Forest Landscapes of the Western USA?

    PubMed

    Baker, William L

    2015-01-01

    Dry forests at low elevations in temperate-zone mountains are commonly hypothesized to be at risk of exceptional rates of severe fire from climatic change and land-use effects. Their setting is fire-prone, they have been altered by land-uses, and fire severity may be increasing. However, where fires were excluded, increased fire could also be hypothesized as restorative of historical fire. These competing hypotheses are not well tested, as reference data prior to widespread land-use expansion were insufficient. Moreover, fire-climate projections were lacking for these forests. Here, I used new reference data and records of high-severity fire from 1984-2012 across all dry forests (25.5 million ha) of the western USA to test these hypotheses. I also approximated projected effects of climatic change on high-severity fire in dry forests by applying existing projections. This analysis showed the rate of recent high-severity fire in dry forests is within the range of historical rates, or is too low, overall across dry forests and individually in 42 of 43 analysis regions. Significant upward trends were lacking overall from 1984-2012 for area burned and fraction burned at high severity. Upward trends in area burned at high severity were found in only 4 of 43 analysis regions. Projections for A.D. 2046-2065 showed high-severity fire would generally be still operating at, or have been restored to historical rates, although high projections suggest high-severity fire rotations that are too short could ensue in 6 of 43 regions. Programs to generally reduce fire severity in dry forests are not supported and have significant adverse ecological impacts, including reducing habitat for native species dependent on early-successional burned patches and decreasing landscape heterogeneity that confers resilience to climatic change. Some adverse ecological effects of high-severity fires are concerns. Managers and communities can improve our ability to live with high-severity fire in

  12. Measurements of reactive trace gases and variable O3 formation rates in some South Carolina biomass burning plumes

    NASA Astrophysics Data System (ADS)

    Akagi, S. K.; Yokelson, R. J.; Burling, I. R.; Meinardi, S.; Simpson, I.; Blake, D. R.; McMeeking, G. R.; Sullivan, A.; Lee, T.; Kreidenweis, S.; Urbanski, S.; Reardon, J.; Griffith, D. W. T.; Johnson, T. J.; Weise, D. R.

    2012-09-01

    In October-November 2011 we measured trace gas emission factors from seven prescribed fires in South Carolina (SC), US, using two Fourier transform infrared spectrometer (FTIR) systems and whole air sampling (WAS) into canisters followed by gas-chromatographic analysis. A total of 97 trace gas species were quantified from both airborne and ground-based sampling platforms, making this one of the most detailed field studies of fire emissions to date. The measurements include the first emission factors for a suite of monoterpenes produced by heating vegetative fuels during field fires. The first quantitative FTIR observations of limonene in smoke are reported along with an expanded suite of monoterpenes measured by WAS including α-pinene, β-pinene, limonene, camphene, 4-carene, and myrcene. The known chemistry of the monoterpenes and their measured abundance of 0.4-27.9% of non-methane organic compounds (NMOCs) and ~21% of organic aerosol (mass basis) suggests that they impacted secondary formation of ozone (O3), aerosols, and small organic trace gases such as methanol and formaldehyde in the sampled plumes in first few hours after emission. The variability in the initial terpene emissions in the SC fire plumes was high and, in general, the speciation of the initially emitted gas-phase NMOCs was 13-195% different from that observed in a similar study in nominally similar pine forests in North Carolina ~20 months earlier. It is likely that differences in stand structure and environmental conditions contributed to the high variability observed within and between these studies. Similar factors may explain much of the variability in initial emissions in the literature. The ΔHCN/ΔCO emission ratio, however, was found to be fairly consistent with previous airborne fire measurements in other coniferous-dominated ecosystems, with the mean for these studies being 0.90 ± 0.06%, further confirming the value of HCN as a biomass burning tracer. The SC results also support an

  13. Measurements of reactive trace gases and variable O3 formation rates in some South Carolina biomass burning plumes

    NASA Astrophysics Data System (ADS)

    Akagi, S. K.; Yokelson, R. J.; Burling, I. R.; Meinardi, S.; Simpson, I.; Blake, D. R.; McMeeking, G. R.; Sullivan, A.; Lee, T.; Kreidenweis, S.; Urbanski, S.; Reardon, J.; Griffith, D. W. T.; Johnson, T. J.; Weise, D. R.

    2013-02-01

    In October-November 2011 we measured trace gas emission factors from seven prescribed fires in South Carolina (SC), US, using two Fourier transform infrared spectrometer (FTIR) systems and whole air sampling (WAS) into canisters followed by gas-chromatographic analysis. A total of 97 trace gas species were quantified from both airborne and ground-based sampling platforms, making this one of the most detailed field studies of fire emissions to date. The measurements include the first emission factors for a suite of monoterpenes produced by heating vegetative fuels during field fires. The first quantitative FTIR observations of limonene in smoke are reported along with an expanded suite of monoterpenes measured by WAS including α-pinene, β-pinene, limonene, camphene, 4-carene, and myrcene. The known chemistry of the monoterpenes and their measured abundance of 0.4-27.9% of non-methane organic compounds (NMOCs) and ~ 21% of organic aerosol (mass basis) suggests that they impacted secondary formation of ozone (O3), aerosols, and small organic trace gases such as methanol and formaldehyde in the sampled plumes in the first few hours after emission. The variability in the initial terpene emissions in the SC fire plumes was high and, in general, the speciation of the initially emitted gas-phase NMOCs was 13-195% different from that observed in a similar study in nominally similar pine forests in North Carolina ~ 20 months earlier. It is likely that differences in stand structure and environmental conditions contributed to the high variability observed within and between these studies. Similar factors may explain much of the variability in initial emissions in the literature. The ΔHCN/ΔCO emission ratio, however, was found to be fairly consistent with previous airborne fire measurements in other coniferous-dominated ecosystems, with the mean for these studies being 0.90 ± 0.06%, further confirming the value of HCN as a biomass burning tracer. The SC results also

  14. Effects of Bi-NTO complex on thermal behaviors, nonisothermal reaction kinetics and burning rates of NG/TEGDN/NC propellant.

    PubMed

    Yi, Jian-Hua; Zhao, Feng-Qi; Hong, Wei-Liang; Xu, Si-Yu; Hu, Rong-Zu; Chen, Zhi-Qun; Zhang, La-Ying

    2010-04-15

    A bismuth 3-nitro-1,2,4-triazol-5-one (Bi-NTO) complex was prepared and characterized, and its effects on the thermal behaviors, non-isothermal decomposition reaction kinetics, and burning rates of the double-base (DB) propellant containing the mixed ester of triethyleneglycol dinitrate (TEGDN) and nitroglycerin (NG) with Bi-NTO complex as a ballistic modifier were investigated by thermogravimetry and derivative thermogravimetry (TG-DTG), and differential scanning calorimetry (DSC). The results show that Bi-NTO complex can increase the decomposition heat by 140 J g(-1), and it can change the decomposition reaction mechanism function, the kinetic parameters and kinetic equation of the propellant under 0.1 MPa. Combustion experiment shows that Bi-NTO complex can increase the burning rate and reduce the pressure exponent of the NG/TEGDN/NC propellant effectively, with the increase of the catalysis efficiency by 40%. Crown Copyright 2009. Published by Elsevier B.V. All rights reserved.

  15. Effects of the Distributions of Energy or Charge Transfer Rates on Spectral Hole Burning in Pigment-Protein Complexes at Low Temperatures

    SciTech Connect

    Herascu, N.; Ahmouda, S.; Picorel, R.; Seibert, M.; Jankowiak, R.; Zazubovich, V.

    2011-12-22

    Effects of the distributions of excitation energy transfer (EET) rates (homogeneous line widths) on the nonphotochemical (resonant) spectral hole burning (SHB) processes in photosynthetic chlorophyll-protein complexes (reaction center [RC] and CP43 antenna of Photosystem II from spinach) are considered. It is demonstrated that inclusion of such a distribution results in somewhat more dispersive hole burning kinetics. More importantly, however, inclusion of the EET rate distributions strongly affects the dependence of the hole width on the fractional hole depth. Different types of line width distributions have been explored, including those resulting from Foerster type EET between weakly interacting pigments as well as Gaussian ones, which may be a reasonable approximation for those resulting, for instance, from so-called extended Foerster models. For Gaussian line width distributions, it is possible to determine the parameters of both line width and tunneling parameter distributions from SHB data without a priori knowledge of any of them. Concerning more realistic asymmetric distributions, we demonstrate, using the simple example of CP43 antenna, that one can use SHB modeling to estimate electrostatic couplings between pigments and support or exclude assignment of certain pigment(s) to a particular state.

  16. The thermal decomposition of 1,3,5-trinitrohexahydro-1,3,5-triazine (RDX) and RDXd6 at high temperatures. [burning rate

    NASA Technical Reports Server (NTRS)

    Miller, P. J.; Nauflett, G. W.; Carlson, D. W.; Brasch, J. W., Sr.

    1980-01-01

    The ballistics behavior of nitramine propellants containing RDX in an inert binder was examined. It is shown that at 2000 to 5000 psi, depending on the particle size, a slope break or discontinuity in the log burning rate versus log pressure curve occurs. It is shown that at higher pressures the nitramine decomposition proceeds predominately by C-N bond rupture and gives CH2 and N20. At still higher pressures (after the slope break) the decomposition proceeds by N-N rupture. The decomposition of RDX was investigated from 170 to 800 C at atmospheric pressure. The major decomposition products were CH2, CO, CO2, N20, N2, and H20. The ratio of the products varied with the pyrolysis rate and temperature.

  17. American Burn Association

    MedlinePlus

    ... by burn injury. Donate today The American Burn Association Web site contains general information for burn care ... local burn center or hospital. © 2017 American Burn Association. All rights reserved.

  18. MALIGNANT DEGENERATION IN BURN SCARS

    PubMed Central

    Castañares, Salvador

    1961-01-01

    The malignant potential of burn scars has been recognized since Marjolin's classical description of cancer arising in several types of post-traumatic scars. With improved burn therapy since the last war, there has been a higher survival rate of severe burns with proportionate increase in cancer associated with burn scars. This will create increasing problems of permanent disability and compensation. The younger the patient at the time of the burn, the longer the time required for the cancer to develop. Acute cancer development in burn scars has been reported after a four-week interval. Cancer may develop from six weeks to fifty years or more. The etiology of cancer in burn scars is not known. The most important clinical finding is the fact that most of the burn cancers occur in areas which were not grafted. The most common type of cancer encountered in burn scars is squamous cell carcinoma, which forms in Marjolin ulcers. Basal cell carcinoma may develop in the most superficial of burn scars. Treatment should be directed primarily to prompt and adequate skin grafting in all deep burns in order to prevent malignant degeneration of the burn scars. Once it has developed the treatment is the same as for other malignancies which are not associated with burns. Wide surgical excision with block dissection of the regional lymph nodes when they are involved is the treatment of choice. The prognosis of burn scar cancer is poor, once the process has extended because of early and distant metastasis. ImagesFigure 1.Figure 2.Figure 2.Figure 3.Figure 3.Figure 4. PMID:13691372

  19. Biomass Burning

    NASA Technical Reports Server (NTRS)

    Levine, Joel S.; Cofer, Wesley R., III; Pinto, Joseph P.

    1993-01-01

    Biomass burning may be the overwhelming regional or continental-scale source of methane (CH4) as in tropical Africa and a significant global source of CH4. Our best estimate of present methane emissions from biomass burning is about 51.9 Tg/yr, or 10% of the annual methane emissions to the atmosphere. Increased frequency of fires that may result as the Earth warms up may result in increases in this source of atmospheric methane.

  20. Emerging Infections in Burns

    PubMed Central

    Branski, Ludwik K.; Al-Mousawi, Ahmed; Rivero, Haidy; Jeschke, Marc G.; Sanford, Arthur P.

    2009-01-01

    Abstract Background Patients who suffer severe burns are at higher risk for local and systemic infections. In recent years, emerging resistant pathogens have forced burn care providers world wide to search for alternative forms of treatment. Multidrug-resistant Staphylococcus aureus, Pseudomonas aeruginosa, Acinetobacter spp., and various fungal strains have been the major contributors to the increase in morbidity and mortality rates. Multi-drug-resistant S. aureus remains the major cause of gram-positive burn wound infections world wide. Treatment strategies include rigorous isolation protocols and new types of antibiotics where necessary. Methods We reviewed 398 severely burned patients (burns >40% total body surface area [TBSA]) admitted to our hospital between 2000 and 2006. Patients who did not contract multi-drug-resistant gram-negative organisms during their hospital course and received our standard antibiotic regimen—vancomycin and piperacillin/tazobactam—served as controls (piperacillin/tazobactam; n = 280). The treatment group consisted of patients who, during their acute hospital stay, developed infections with multi-drug-resistant gram-negative pathogens and were treated with vancomycin and colistin for at least three days (colistin; n = 118). Results Gram-negative organisms continue to cause the most severe infections in burn patients. Colistin has re-emerged as a highly effective antibiotic against multiresistant Pseudomonas and Acinetobacter infections of burns. Patients who required colistin therapy had a significantly larger average total and full-thickness burn than patients treated with piperacillin/tazobactam and vancomycin, and the mortality rate was significantly higher in the colistin group (p < 0.05). However, there was no significant difference between the colistin and piperacillin/tazobactam groups in the incidence of neurotoxicity, hepatic toxicity, or nephrotoxicity. The main fungal pathogens in burn patients are Candida

  1. Control in the Rate-Determining Step Provides a Promising Strategy To Develop New Catalysts for CO2 Hydrogenation: A Local Pair Natural Orbital Coupled Cluster Theory Study.

    PubMed

    Mondal, Bhaskar; Neese, Frank; Ye, Shengfa

    2015-08-03

    The development of efficient catalysts with base metals for CO2 hydrogenation has always been a major thrust of interest. A series of experimental and theoretical work has revealed that the catalytic cycle typically involves two key steps, namely, base-promoted heterolytic H2 splitting and hydride transfer to CO2, either of which can be the rate-determining step (RDS) of the entire reaction. To explore the determining factor for the nature of RDS, we present herein a comparative mechanistic investigation on CO2 hydrogenation mediated by [M(H)(η(2)-H2)(PP3(Ph))](n+) (M = Fe(II), Ru(II), and Co(III); PP3(Ph) = tris(2-(diphenylphosphino)phenyl)phosphine) type complexes. In order to construct reliable free energy profiles, we used highly correlated wave function based ab initio methods of the coupled cluster type alongside the standard density functional theory. Our calculations demonstrate that the hydricity of the metal-hydride intermediate generated by H2 splitting dictates the nature of the RDS for the Fe(II) and Co(III) systems, while the RDS for the Ru(II) catalyst appears to be ambiguous. CO2 hydrogenation catalyzed by the Fe(II) complex that possesses moderate hydricity traverses an H2-splitting RDS, whereas the RDS for the high-hydricity Co(III) species is found to be the hydride transfer. Thus, our findings suggest that hydricity can be used as a practical guide in future catalyst design. Enhancing the electron-accepting ability of low-hydricity catalysts is likely to improve their catalytic performance, while increasing the electron-donating ability of high-hydricity complexes may speed up CO2 conversion. Moreover, we also established the active roles of base NEt3 in directing the heterolytic H2 splitting and assisting product release through the formation of an acid-base complex.

  2. Catalyst Additives to Enhance Mercury Oxidation and Capture

    SciTech Connect

    Jared W. Cannon; Thomas K. Gale

    2005-06-30

    Preliminary research has shown that SCR catalysts employed for nitrogen-oxide reduction can effectively oxidize mercury. This report discusses initial results from fundamental investigations into the behavior of mercury species in the presence of SCR catalysts at Southern Research Institute. The testing was performed at Southern Research's Catalyst Test Facility, a bench-scale reactor capable of simulating gas-phase reactions occurring in coal-fired utility pollution-control equipment. Three different SCR catalysts are currently being studied in this project--honeycomb-type, plate-type, and a hybrid-type catalyst. The catalysts were manufactured and supplied by Cormetech Inc., Hitachi America Ltd., and Haldor-Topsoe Inc., respectively. Parametric testing was performed to investigate the contribution of flue-gas chemistry on mercury oxidation via SCR catalysts. Methods and procedures for experimental testing continue to be developed to produce the highest quality mercury-oxidation data. During this past quarter, it was discovered that long periods (12 - 24 hours) are required to equilibrate the catalysts in the system. In addition, after the system has been equilibrated, operational changes to temperature, gas concentration, or flow rate shifts the equilibrium, and steady-state must be reestablished, which can require as much as twelve additional hours per condition change. In the last quarter of testing, it was shown that the inclusion of ammonia had a strong effect on the oxidation of mercury by SCR catalysts, both in the short-term (a transitional period of elemental and oxidized mercury off gassing) and the long-term (less steady-state mercury oxidation). All experiments so far have focused on testing the catalysts in a simulated Powder River Basin (PRB) flue-gas environment, which contains lower sulfur and chlorine than produced by other coals. In the next quarter, parametric testing will be expanded to include flue gases simulating power plants burning

  3. CAD tool for burn diagnosis.

    PubMed

    Acha, Begoña; Serrano, Carmen; Acha, José I; Roa, Laura M

    2003-07-01

    In this paper a new system for burn diagnosis is proposed. The aim of the system is to separate burn wounds from healthy skin, and the different types of burns (burn depths) from each other, identifying each one. The system is based on the colour and texture information, as these are the characteristics observed by physicians in order to give a diagnosis. We use a perceptually uniform colour space (L*u*v*), since Euclidean distances calculated in this space correspond to perceptually colour differences. After the burn is segmented, some colour and texture descriptors are calculated and they are the inputs to a Fuzzy-ARTMAP neural network. The neural network classifies them into three types of bums: superficial dermal, deep dermal and full thickness. Clinical effectiveness of the method was demonstrated on 62 clinical burn wound images obtained from digital colour photographs, yielding an average classification success rate of 82% compared to expert classified images.

  4. Highly efficient and robust molecular ruthenium catalysts for water oxidation.

    PubMed

    Duan, Lele; Araujo, Carlos Moyses; Ahlquist, Mårten S G; Sun, Licheng

    2012-09-25

    Water oxidation catalysts are essential components of light-driven water splitting systems, which could convert water to H(2) driven by solar radiation (H(2)O + hν → 1/2O(2) + H(2)). The oxidation of water (H(2)O → 1/2O(2) + 2H(+) + 2e(-)) provides protons and electrons for the production of dihydrogen (2H(+) + 2e(-) → H(2)), a clean-burning and high-capacity energy carrier. One of the obstacles now is the lack of effective and robust water oxidation catalysts. Aiming at developing robust molecular Ru-bda (H(2)bda = 2,2'-bipyridine-6,6'-dicarboxylic acid) water oxidation catalysts, we carried out density functional theory studies, correlated the robustness of catalysts against hydration with the highest occupied molecular orbital levels of a set of ligands, and successfully directed the synthesis of robust Ru-bda water oxidation catalysts. A series of mononuclear ruthenium complexes [Ru(bda)L(2)] (L = pyridazine, pyrimidine, and phthalazine) were subsequently synthesized and shown to effectively catalyze Ce(IV)-driven [Ce(IV) = Ce(NH(4))(2)(NO(3))(6)] water oxidation with high oxygen production rates up to 286 s(-1) and high turnover numbers up to 55,400.

  5. Highly efficient and robust molecular ruthenium catalysts for water oxidation

    PubMed Central

    Duan, Lele; Araujo, Carlos Moyses; Ahlquist, Mårten S.G.; Sun, Licheng

    2012-01-01

    Water oxidation catalysts are essential components of light-driven water splitting systems, which could convert water to H2 driven by solar radiation (H2O + hν → 1/2O2 + H2). The oxidation of water (H2O → 1/2O2 + 2H+ + 2e-) provides protons and electrons for the production of dihydrogen (2H+ + 2e- → H2), a clean-burning and high-capacity energy carrier. One of the obstacles now is the lack of effective and robust water oxidation catalysts. Aiming at developing robust molecular Ru-bda (H2bda = 2,2′-bipyridine-6,6′-dicarboxylic acid) water oxidation catalysts, we carried out density functional theory studies, correlated the robustness of catalysts against hydration with the highest occupied molecular orbital levels of a set of ligands, and successfully directed the synthesis of robust Ru-bda water oxidation catalysts. A series of mononuclear ruthenium complexes [Ru(bda)L2] (L = pyridazine, pyrimidine, and phthalazine) were subsequently synthesized and shown to effectively catalyze CeIV-driven [CeIV = Ce(NH4)2(NO3)6] water oxidation with high oxygen production rates up to 286 s-1 and high turnover numbers up to 55,400. PMID:22753518

  6. Burn Teams and Burn Centers: The Importance of a Comprehensive Team Approach to Burn Care

    PubMed Central

    Al-Mousawi, Ahmed M.; Mecott-Rivera, Gabriel A.; Jeschke, Marc G.; Herndon, David N.

    2009-01-01

    Synopsis Advances in burn care have been colossal, but while extra work is needed, it is clear that the organized effort of burn teams can continue making improvements in survival rates and quality of life possible for patients. Burn patients are unique, representing the most severe model of trauma,33 and hence this necessitates treatment in the best facilities available for that endeavor. Burn centers have developed to meet these intricate needs but can only function productively and most efficiently through well organized, multifaceted, patient-centered teams in areas of clinical care and research. PMID:19793550

  7. Decomposition rate comparisons between frequently burned and unburned areas of uneven-aged loblolly pine stands in southeastern Arkansas

    Treesearch

    Miclele Renschin; Hal O. Leichty; Michael G. Shelton

    2001-01-01

    Although fire has been used extensively over long periods of time in loblolly pine (Pinis taeda L.) ecosystems, little is known concerning the effects of frequent fire use on nutrient cycling and decomposition. To better understand the long-term effects of fire on these processes, foliar litter decomposition rates were quantified in a study...

  8. Fast burning propellants

    SciTech Connect

    Colgate, S.A.; Roos, G.E.

    1987-07-21

    A solid or semisolid propellant is described comprising grains of propellant or propellant components bonded together to create voids within the propellant volume. The grains are of near-uniform size and have less than about a 20% size variation between the largest and smallest grains, the voids comprising from about 10% to about 50% of the propellant volume. The grains are bonded together with sufficient strength to substantially delay the fluidization of the propellant by the onset of Taylor unstable burning. The propellant has a rapid burn rate of from about 10 cm sec/sup -1/ to about 10/sup 4/cm sec/sup -1/.

  9. Outcomes of outpatient management of pediatric burns.

    PubMed

    Brown, Matthew; Coffee, Tammy; Adenuga, Paul; Yowler, Charles J

    2014-01-01

    The literature surrounding pediatric burns has focused on inpatient management. The goal of this study is to characterize the population of burned children treated as outpatients and assess outcomes validating this method of burn care. A retrospective review of 953 patients treated the burn clinic and burn unit of a tertiary care center. Patient age, burn etiology, burn characteristics, burn mechanism, and referral pattern were recorded. The type of wound care and incidence of outcomes including subsequent hospital admission, infection, scarring, and surgery served as the primary outcome data. Eight hundred and thirty children were treated as outpatients with a mean time of 1.8 days for the evaluation of burn injury in our clinic. Scalds accounted for 53% of the burn mechanism, with burns to the hand/wrist being the most frequent area involved. The mean percentage of TBSA was 1.4% for the outpatient cohort and 8% for the inpatient cohort. Burns in the outpatient cohort healed with a mean time of 13.4 days. In the outpatient cohort, nine (1%) patients had subsequent admissions and three (0.4%) patients had concern for infection. Eight patients from the outpatient cohort were treated with excision and grafting. The vast majority of pediatric burns are small, although they may often involve more critical areas such as the face and hand. Outpatient wound care is an effective treatment strategy which results in low rates of complications and should become the standard of care for children with appropriate burn size and home support.

  10. Infection in Burns

    PubMed Central

    Norbury, William; Herndon, David N.; Tanksley, Jessica; Jeschke, Marc G.

    2016-01-01

    Abstract Background: Developments in critical care and surgical approaches to treating burn wounds, together with newer antimicrobial treatments, have significantly reduced the morbidity and mortality rates associated with this injury. Methods: Review of the pertinent English-language literature. Results: Several resistant organisms have emerged as the maleficent cause of invasive infection in burn patients, including methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus, Pseudomonas, Acinetobacter, non-albicans Candida spp., and Aspergillus. Advances in antimicrobial therapies and the release of new classes of antibiotics have certainly added to the armamentarium of therapeutic resources for the clinician. Conclusion: Strict infection control measures, constant wound surveillance with regular sampling of tissues for quantitative culture, and early excision and wound closure remain the principal adjuncts to control of invasive infections in burn patients. PMID:26978531

  11. [Polytraumatized burn injury victims].

    PubMed

    Ziegenthaler, H; Neumann, U; Fritzsche, U; Sühnel, B

    2005-09-01

    Most polytraumatized burn injury persons aged 30-40 years who have suffered a burn or a burn-like injury are stigmatized by serious functional deficits, temporary loss of their social independence, injury-associated psychological reactions of different levels, and unusual reversible deficits in their higher cortical functions. The result is a prolonged stage of acute treatment and rehabilitation as well as very often the lifelong need for highly specialized care by physicians and other medical professionals. Accordingly, the deficits in any individual case are high and in spite of the low case rate (approximately 300-400 cases/ year) these accidents have a high impact on society as a whole, resulting in a significant financial burden for the social security system, insurance funds, and pension funds.

  12. Simulations of the Neutral-beam-induced Rotation, Radial Electric Field, and Flow Shearing Rate in Next-step Burning Plasmas

    SciTech Connect

    R.V. Budny

    2002-08-13

    Toroidal rotation of plasmas in present tokamaks is beneficial for increasing the stability to wall-induced MHD and appears to reduce the anomalous transport associated with micro-turbulence. This paper calculates the toroidal rotation expected from neutral-beam injection in the proposed FIRE and ITER-FEAT tokamak reactors. Self-consistent burning plasmas for these tokamaks have been constructed using the TRANSP plasma analysis code. Neutral-beam injection has been proposed for FIRE and ITER-FEAT. The neutral-beam-induced torques are computed, and assumptions for the anomalous transport of toroidal angular momentum are used to calculate the toroidal rotation profiles. The central Mach numbers are about 3-8%. The ratio of the rotation speed to the Alfvin speed is less than 1%. Assuming neoclassical poloidal rotation and force balance, the radial electric field and flow shearing rate are calculated. Peak shearing rates near the outboard edge are in the 10-100 krad/s range.

  13. Burn Wise - Outreach Materials

    EPA Pesticide Factsheets

    Burn Wise outreach material. Burn Wise is a partnership program of that emphasizes the importance of burning the right wood, the right way, in the right wood-burning appliance to protect your home, health, and the air we breathe.

  14. Burn Wise - Educational Materials

    EPA Pesticide Factsheets

    Burn Wise outreach material. Burn Wise is a partnership program of that emphasizes the importance of burning the right wood, the right way, in the right wood-burning appliance to protect your home, health, and the air we breathe.

  15. Prescribed burning

    Treesearch

    James D. Haywood; Finis Harris

    2002-01-01

    This presentation on prescribed burning is a cooperative effort of the USDA Forest Service, Southern Research Station and Kisatchie National Forest; Louisiana State University Agricultural Center; and the Joint Fire Science Program. The CD includes three methods of delivery: slides, Power Point presentation, and script only.

  16. Burning Man

    ERIC Educational Resources Information Center

    Cech, Scott J.

    2006-01-01

    Former Baltimore cop and teacher Ed Burns isn't a masochist. The writer-producer for "The Wire," a critically applauded HBO series about life and death on the streets of Baltimore, is just feverishly trying to save public schools. He thinks American education is hopelessly screwed up, but that it's also the country's only hope. So it…

  17. Burning Man

    ERIC Educational Resources Information Center

    Cech, Scott J.

    2006-01-01

    Former Baltimore cop and teacher Ed Burns isn't a masochist. The writer-producer for "The Wire," a critically applauded HBO series about life and death on the streets of Baltimore, is just feverishly trying to save public schools. He thinks American education is hopelessly screwed up, but that it's also the country's only hope. So it…

  18. Cortisol and Corticotrophin in Burned Patients,

    DTIC Science & Technology

    1982-04-01

    BASIL A. PRUITT, JR., M.D., AND ARTHUR D. MASON, JR., M.D. < In a study of 36 men burned in a fire, based on sequential early morning samples, plasma ...cortisol concentration was elevated in proportion to burn size. Plasma corticotrophin (ACTH) was not correlated with burn size, suggesting that factors...in proportion to burn size. Although plasma cortisol Was positively correlated with metabolic rate and with temperature, this appeared to result from a

  19. Pediatric burns: Kids' Inpatient Database vs the National Burn Repository.

    PubMed

    Soleimani, Tahereh; Evans, Tyler A; Sood, Rajiv; Hartman, Brett C; Hadad, Ivan; Tholpady, Sunil S

    2016-04-01

    Burn injuries are one of the leading causes of morbidity and mortality in young children. The Kids' Inpatient Database (KID) and National Burn Repository (NBR) are two large national databases that can be used to evaluate outcomes and help quality improvement in burn care. Differences in the design of the KID and NBR could lead to differing results affecting resultant conclusions and quality improvement programs. This study was designed to validate the use of KID for burn epidemiologic studies, as an adjunct to the NBR. Using the KID (2003, 2006, and 2009), a total of 17,300 nonelective burn patients younger than 20 y old were identified. Data from 13,828 similar patients were collected from the NBR. Outcome variables were compared between the two databases. Comparisons revealed similar patient distribution by gender, race, and burn size. Inhalation injury was more common among the NBR patients and was associated with increased mortality. The rates of respiratory failure, wound infection, cellulitis, sepsis, and urinary tract infection were higher in the KID. Multiple regression analysis adjusting for potential confounders demonstrated similar mortality rate but significantly longer length of stay for patients in the NBR. Despite differences in the design and sampling of the KID and NBR, the overall demographic and mortality results are similar. The differences in complication rate and length of stay should be explored by further studies to clarify underlying causes. Investigations into these differences should also better inform strategies to improve burn prevention and treatment. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Catalytic reforming catalyst

    SciTech Connect

    Buss, W.C.; Kluksdahl, H.E.

    1980-12-09

    An improved catalyst, having a reduced fouling rate when used in a catalytic reforming process, said catalyst comprising platinum disposed on an alumina support wherein the alumina support is obtained by removing water from aluminum hydroxide produced as a by-product from a ziegler higher alcohol synthesis reaction, and wherein the alumina is calcined at a temperature of 1100-1400/sup 0/F so as to have a surface area of 165 to 215 square meters per gram.

  1. Acetic acid effects on enhancement of growth rate and reduction of amorphous carbon deposition on CNT arrays along a growth window in a floating catalyst reactor

    NASA Astrophysics Data System (ADS)

    Maghrebi, Morteza; Khodadadi, Abbas Ali; Mortazavi, Yadollah; Sane, Ali; Rahimi, Mohsen; Shirazi, Yaser; Tsakadze, Zviad; Mhaisalkar, Subodh

    2009-11-01

    The mm-long carbon nanotube (CNT) arrays were grown in a floating catalyst reactor, using xylene-ferrocene and a small amount of acetic acid as the feed. The CNT arrays deposited on a quartz substrate at several positions along the reactor were extensively characterized using Raman spectroscopy, scanning electron microscopy, X-ray diffraction, high-resolution transmission electron microscopy, and optical microscopy. Various characterization methods consistently reveal that the acetic acid additive to the feed alleviates deposition of amorphous carbon layer, which gradually thickens CNTs along the reactor. The acetic acid also resulted in a higher growth rate along the so-called growth window, where CNT arrays are deposited on the quartz substrate. High-performance liquid chromatography of extracted byproducts (PAHs) confirmed the presence of some polycyclic aromatic hydrocarbons. The solid weight of PAHs decreased upon addition of ferrocene as the catalyst precursor, as well as of acetic acid to xylene feed. The results suggest that primary light products of xylene pyrolysis can be competitive reactants for both catalytic and subsequent pyrolytic reactions. They may also be more efficient feeds for CNT growth than xylene itself.

  2. Efficacy of moist exposed burn ointment on burns.

    PubMed

    Zhang, Hong-Qi; Yip, Tsui-Pik; Hui, Irene; Lai, Vincy; Wong, Ann

    2005-01-01

    In this study, we sought to test the medical efficacy of a Chinese medical herb product, moist exposed burn ointment (MEBO), on wound healing rate and infection control in burn injury. Standardized deep burn wounds were created on the back skin of rats by applying a hot brass bar for 12 to 18 seconds. MEBO was applied four times per day and compared with petroleum jelly, silver sulfadiazine, and dry exposure therapy. Under such a controlled setting, although MEBO had a better wound healing rate than the dry exposure treatment, it did not show the medical advantage statistically, as has been claimed, over the other two treatments (P > .05), either in terms of wound healing rate or bacterial control. We conclude that the MEBO is not suitable for deep burn wound treatment, particularly when infection is a concern.

  3. Preparation of Partial-Thickness Burn Wounds in Rodents Using a New Experimental Burning Device.

    PubMed

    Sakamoto, Michiharu; Morimoto, Naoki; Ogino, Shuichi; Jinno, Chizuru; Kawaguchi, Atsushi; Kawai, Katsuya; Suzuki, Shigehiko

    2016-06-01

    The manual application of hot water or hot metal to an animal's skin surface is often used to prepare burn wound models. However, manual burn creation is subject to human variability. We developed a new device that can control the temperature, time, and pressure of contact to produce precise and reproducible animal burn wounds and investigated the conditions required to prepare various burn wounds using our new device. We prepared burn wounds on F344 rats using 3 contact times 2, 4, and 10 seconds using a stamp heated to 80°C. We observed the wound-healing process macroscopically and histologically and evaluated the burn depth using a laser speckle contrast-imaging device, which evaluated the blood flow of the wound. The changes in the burned area over time, tissue perfusion of the burn wounds, histological evaluation of the burn depth by hematoxylin-eosin and azocarmine and aniline blue staining, and the epithelialization rate (the ratio of the epithelialized area to the wound length) were evaluated on histological sections. Results indicated that the burn wounds prepared with contact times of 2, 4, and 10 seconds corresponded to superficial dermal burns, deep dermal burns, and full-thickness burns, respectively. We demonstrated that partial- and full-thickness burn wounds can be precisely and reproducibly created with our new automated burning device.

  4. Management of burns in the elderly

    PubMed Central

    Abu-Sittah, G.S.; Chahine, F.M.; Janom, H.

    2016-01-01

    Summary Burns are one of the most devastating forms of trauma worldwide. While geriatric burns are uncommon in the developing world - accounting for less than 5% of burns in South Asian and Middle Eastern countries - they account for almost 20% of burns in economically developed countries such as the USA. The elderly population in general is at higher risk for burn injury, moreover mortality rate, as well as severity of complications, is more pronounced in this group of patients. A review of the literature was conducted to evaluate risk factors as well as pathophysiological and immunological conditions that affect response to burn injury in the elderly population. Surgical and medical interventions used for the management of geriatric burns remain a field of controversy and ongoing debate. Improvement of burn management with reduction in mortality in this age group warrants addressing survivors’ quality of life, with a special focus on rehabilitation and support. PMID:28289356

  5. Burn Resuscitation

    PubMed Central

    2011-01-01

    Fluid resuscitation following burn injury must support organ perfusion with the least amount of fluid necessary and the least physiological cost. Under resuscitation may lead to organ failure and death. With adoption of weight and injury size-based formulas for resuscitation, multiple organ dysfunction and inadequate resuscitation have become uncommon. Instead, administration of fluid volumes well in excess of historic guidelines has been reported. A number of strategies including greater use of colloids and vasoactive drugs are now under investigation to optimize preservation of end organ function while avoiding complications which can include respiratory failure and compartment syndromes. Adjuncts to resuscitation, such as antioxidants, are also being investigated along with parameters beyond urine output and vital signs to identify endpoints of therapy. Here we briefly review the state-of-the-art and provide a sample of protocols now under investigation in North American burn centers. PMID:22078326

  6. Burn Resuscitation

    DTIC Science & Technology

    2009-01-01

    areas involving large areas of skin the patient is exposed to death first from shock . . .’’ [10]. In describing the pathophysiology leading to the shock...state seen in burns he postulated that various irritants , mental and physical, caused vasomotor paresis leading to accumulation of blood in the...resuscitation volumes. Subsequent studies suggested a decrease in abdominal compartment syndrome (ACS). Oda et al., in 2006, published their experience

  7. Reforming catalysts

    SciTech Connect

    Givens, E.N.; Plank, C.J.; Rosinski, E.J.

    1980-03-04

    Crystalline aluminosilicate zeolites are mixed with conventional reforming catalysts to produce new catalytic compositions with high catalytic activity and selectivity and excellent aging characteristics. These new catalytic compositions may be utilized alone or in conjunction with conventional reforming catalysts. The acidic activity of the total catalyst system is controlled within defined limits. When so controlled the utility of these catalyst systems in reforming hydrocarbon mixtures is to reduce the C1 and C2 concentrations in reformer gas product, while increasing the C3 and C4 concentrations and maintaining high liquid yield at high octane numbers.

  8. Occupational Burns Treated in Emergency Departments

    PubMed Central

    Reichard, Audrey A.; Konda, Srinivas; Jackson, Larry L.

    2015-01-01

    Background Despite reported declines, occupational burn injuries remain a workplace safety concern. More severe burns may result in costly medical treatment and long-term physical and psychological consequences. Methods We used the National Electronic Injury Surveillance System—Occupational Supplement to produce national estimates of burns treated in emergency departments (EDs). We analyzed data trends from 1999 to 2008 and provided detailed descriptions of 2008 data. Results From 1999 to 2008 there were 1,132,000 (95% CI: ±192,300) nonfatal occupational burns treated in EDs. Burn numbers and rates declined approximately 40% over the 10 years. In 2008, men and younger workers 15–24 years old had the highest rates. Scalds and thermal burns accounted for more than 60% of burns. Accommodation and food service, manufacturing, and construction industries had the largest number of burns. Conclusions Despite declining burn rates, emphasis is needed on reducing burn hazards to young food service workers and using job specific hazard analyses to prevent burns. PMID:25678457

  9. Occupational burns treated in emergency departments.

    PubMed

    Reichard, Audrey A; Konda, Srinivas; Jackson, Larry L

    2015-03-01

    Despite reported declines, occupational burn injuries remain a workplace safety concern. More severe burns may result in costly medical treatment and long-term physical and psychological consequences. We used the National Electronic Injury Surveillance System-Occupational Supplement to produce national estimates of burns treated in emergency departments (EDs). We analyzed data trends from 1999 to 2008 and provided detailed descriptions of 2008 data. From 1999 to 2008 there were 1,132,000 (95% CI: ±192,300) nonfatal occupational burns treated in EDs. Burn numbers and rates declined approximately 40% over the 10 years. In 2008, men and younger workers 15-24 years old had the highest rates. Scalds and thermal burns accounted for more than 60% of burns. Accommodation and food service, manufacturing, and construction industries had the largest number of burns. Despite declining burn rates, emphasis is needed on reducing burn hazards to young food service workers and using job specific hazard analyses to prevent burns. © 2015 Wiley Periodicals, Inc.

  10. Assault by burning in Jordan.

    PubMed

    Haddadin, W

    2012-12-31

    Criminal attacks by burns on women in Jordan are highlighted in this retrospective study carried out of all proved cases of criminal burns in female patients treated at the burn unit of the Royal Rehabilitation Center in Jordan between January 2005 and June 2012. Thirteen patients were included in our study, out of a total of 550 patients admitted, all in the age range of 16-45 yr. Of these 13 women, six were burned by acid throwing, five by hot water, and two by direct flames from fuel thrown over them. Burn percentage ranged from 15 to 75% of the total body surface area, with involvement in most cases of the face and upper trunk. The mean hospital stay was 33 days and the mortality rate was 3/13, i.e. 23%. Violence against women exists in Jordanian society, yet burning assaults are rare. Of these, burning by throwing acid is the most common and most disfiguring act, with a higher mortality rate in domestic environments.

  11. The Burn Wound Microenvironment

    PubMed Central

    Rose, Lloyd F.; Chan, Rodney K.

    2016-01-01

    Significance: While the survival rate of the severely burned patient has improved significantly, relatively little progress has been made in treatment or prevention of burn-induced long-term sequelae, such as contraction and fibrosis. Recent Advances: Our knowledge of the molecular pathways involved in burn wounds has increased dramatically, and technological advances now allow large-scale genomic studies, providing a global view of wound healing processes. Critical Issues: Translating findings from a large number of in vitro and preclinical animal studies into clinical practice represents a gap in our understanding, and the failures of a number of clinical trials suggest that targeting single pathways or cytokines may not be the best approach. Significant opportunities for improvement exist. Future Directions: Study of the underlying molecular influences of burn wound healing progression will undoubtedly continue as an active research focus. Increasing our knowledge of these processes will identify additional therapeutic targets, supporting informed clinical studies that translate into clinical relevance and practice. PMID:26989577

  12. Oxyhydrochlorination catalyst

    DOEpatents

    Taylor, Charles E.; Noceti, Richard P.

    1992-01-01

    An improved catalyst and method for the oxyhydrochlorination of methane is disclosed. The catalyst includes a pyrogenic porous support on which is layered as active material, cobalt chloride in major proportion, and minor proportions of an alkali metal chloride and of a rare earth chloride. On contact of the catalyst with a gas flow of methane, HCl and oxygen, more than 60% of the methane is converted and of that converted more than 40% occurs as monochloromethane. Advantageously, the monochloromethane can be used to produce gasoline boiling range hydrocarbons with the recycle of HCl for further reaction. This catalyst is also of value for the production of formic acid as are analogous catalysts with lead, silver or nickel chlorides substituted for the cobalt chloride.

  13. The dependence of the evolution of Type Ia SN progenitors on the C-burning rate uncertainty and parameters of convective boundary mixing

    NASA Astrophysics Data System (ADS)

    Chen, Michael C.; Herwig, Falk; Denissenkov, Pavel A.; Paxton, Bill

    2014-05-01

    Evolution of a Type Ia supernova (SN Ia) progenitor requires formation of a CO white dwarf (WD), which implies a dependence on the C-burning rate (CBR). It can also be affected by the recently identified possibility of C-flame quenching by convective boundary mixing. We present first results of our study of the combined effect of these two potential sources of uncertainty on the SN Ia progenitor evolution. We consider the possibility that the CBR is higher than its currently recommended value by as much as a factor of 1000 if unidentified resonances are important, or that it is significantly lower because of the hindrance effect. For stellar models that assume the Schwarzschild boundary for convection, the maximum initial mass for the formation of CO WDs increases from Mi ≈ 5.5 M⊙ for the CBR factor of 1000 to Mi ≳ 7.0 M⊙ for the CBR factor of 0.01. For C-flame quenching models, hybrid C-O-Ne WDs form for a range of initial mass of ΔMi ≈ 1 M⊙, which increases a fraction of stars that form WDs capable of igniting C in a thermonuclear runaway. The most extreme case is found for the CBR factor of 0.1 that is supported by the hindrance model. This nuclear physics assumption, combined with C-flame quenching, leads to the formation of a hybrid C-O-Ne WD with a mass of 1.3 M⊙. Such WDs do not need to accrete much mass to reach the Chandrasekhar limit.

  14. Study of insect succession and rate of decomposition on a partially burned pig carcass in an oil palm plantation in Malaysia.

    PubMed

    Heo, Chong Chin; Mohamad, Abdullah Marwi; Ahmad, Firdaus Mohd Salleh; Jeffery, John; Kurahashi, Hiromu; Omar, Baharudin

    2008-12-01

    Insects found associated with corpse can be used as one of the indicators in estimating postmortem interval (PMI). The objective of this study was to compare the stages of decomposition and faunal succession between a partially burnt pig (Sus scrofa Linnaeus) and natural pig (as control). The burning simulated a real crime whereby the victim was burnt by murderer. Two young pigs weighed approximately 10 kg were used in this study. Both pigs died from pneumonia and immediately placed in an oil palm plantation near a pig farm in Tanjung Sepat, Selangor, Malaysia. One pig was partially burnt by 1-liter petrol while the other served as control. Both carcasses were visited twice per day for the first week and once thereafter. Adult flies and larvae on the carcasses were collected and later processed in a forensic entomology laboratory. Results showed that there was no significant difference between the rate of decomposition and sequence of faunal succession on both pig carcasses. Both carcasses were completely decomposed to remain stage after nine days. The species of flies visiting the pig carcasses consisted of blow flies (Chrysomya megacephala, Chrysomya rufifacies, Hemipyrellia ligurriens), flesh fly (Sarcophagidae.), muscid fly (Ophyra spinigera), soldier fly (Hermetia illucens), coffin fly (Phoridae) and scavenger fly (Sepsidae). The only difference noted was in the number of adult flies, whereby more flies were seen in the control carcass. Faunal succession on both pig carcasses was in the following sequence: Calliphoridae, Sarcophagidae, Muscidae, Phoridae and lastly Stratiomyidae. However, there was overlap in the appearance of members of these families. Blowflies continued to oviposit on both carcasses. Hence postmortem interval (PMI) can still be estimated from the partially burnt pig carcass.

  15. Intentional burns in Nepal: a comparative study.

    PubMed

    Lama, Bir Bahadur; Duke, Janine M; Sharma, Narayan Prasad; Thapa, Buland; Dahal, Peeyush; Bariya, Nara Devi; Marston, Wendy; Wallace, Hilary J

    2015-09-01

    Intentional burns injuries are associated with high mortality rates, and for survivors, high levels of physical and psychological morbidity. This study provides a comprehensive assessment of intentional burn admissions to the adult Burns Unit at Bir Hospital, Kathmandu, Nepal, during the period 2002-2013. A secondary data analysis of de-identified data of patients hospitalized at Bir Hospital, Kathmandu, with a burn during the period of 1 January 2002 to 31 August 2013. Socio-demographic, injury and psychosocial factors of patients with intentional and unintentional burns are described and compared. Chi-square tests, Fisher's exact test and Wilcoxon rank sum tests were used to determine statistical significance. There were a total of 1148 burn admissions of which 329 (29%) were for intentional burn, 293 (26%) were self-inflicted and 36 (3%) were due to assault. Mortality rates for intentional burns were approximately three times those for unintentional burns (60 vs. 22%). When compared to unintentional burns, patients with intentional burns were more likely to be female (79 vs. 48%), married (84 vs. 67%), younger (25 vs. 30 years), have more extensive burns (total body surface area, %: 55 vs. 25) and higher mortality (60 vs. 22%). Intentional burns were more likely to occur at home (95 vs. 67%), be caused by fire (96 vs. 77%), and kerosene was the most common accelerant (91 vs. 31%). A primary psychosocial risk factor was identified in the majority of intentional burn cases, with 60% experiencing adjustment problems/interpersonal conflict and 32% with evidence of a pre-existing psychological condition. A record of alcohol/substance abuse related to the patient or other was associated with a greater proportion of intentional burns when compared with unintentional burns (17 vs. 4%). The majority of intentional burn patients were female. Almost all intentional burns occurred in the home and were caused by fire, with kerosene the most common accelerant used. Underlying

  16. Toward Rational Design of 3d Transition Metal Catalysts for CO2 Hydrogenation Based on Insights into Hydricity-Controlled Rate-Determining Steps.

    PubMed

    Mondal, Bhaskar; Neese, Frank; Ye, Shengfa

    2016-06-06

    Carbon dioxide functionalization attracts much interest due to the current environmental and energy challenges. Our earlier work (Mondal, B.; Neese, F.; Ye, S. Inorg. Chem. 2015, 54, 7192-7198) demonstrated that CO2 hydrogenation mediated by base metal catalysts [M(H)(η(2)-H2)(PP3(Ph))](n+) (M = Co(III) and Fe(II), n = 1, 2; PP3(Ph) = tris(2-(diphenylphosphino)phenyl)phosphine) features discrete rate-determining steps (RDSs). Specifically, the reaction with [Co(III)(H)(η(2)-H2)(PP3(Ph))](2+) passes through a hydride-transfer RDS, whereas the conversion with [Fe(II)(H)(η(2)-H2)(PP3(Ph))](+) traverses a H2-splitting RDS. More importantly, we found that the nature and barrier of the RDS likely correlate with the hydride affinity or hydricity of the dihydride intermediate [M(H)2(PP3(Ph))]((n-1)+) generated by H2-splitting. In the present contribution, following this notion we design a series of potential Fe(II) and Co(III) catalysts, for which the respective dihydride species possess differential hydricities, and computationally investigated their reactivity toward CO2 hydrogenation. Our results reveal that lowering the hydrictiy of [Co(III)(H)2(PP3(Ph))](+) by introducing anionic anchors in PP3(Ph) dramatically decreases the hydride-transfer RDS barrier, as shown for the enhanced reactivity of [Co(H)(η(2)-H2)(CP3(Ph))](+) and [Co(H)(η(2)-H2)(SiP3(Ph))](+) (CP3(Ph) = tris(2-(diphenylphosphino)phenyl)methyl, SiP3(Ph) = tris(2-(diphenylphosphino)phenyl)silyl), while the same ligand modification increases the H2-splitting RDS barriers for [Fe(H)(η(2)-H2)(CP3(Ph))] and [Fe(H)(η(2)-H2)(SiP3(Ph))] relative to that for [Fe(H)(η(2)-H2)(PP3(Ph))](+). Conversely, upon increasing the hydricity of [Fe(II)(H)2(PP3(Ph))] by adding an electron-withdrawing group to PP3(Ph), the transformation with [Fe(H)(η(2)-H2)(PP3(PhNO2))](+) (PP3(PhNO2) = tris(2-(diphenylphosphino)-4-nitrophenyl)phosphine) is predicted to encounter a lower barrier for H2-splitting and a higher barrier for

  17. Burning plasmas

    SciTech Connect

    Furth, H.P.; Goldston, R.J.; Zweben, S.J. . Plasma Physics Lab.); Sigmar, D.J. )

    1990-10-01

    The fraction of fusion-reaction energy that is released in energetic charged ions, such as the alpha particles of the D-T reaction, can be thermalized within the reacting plasma and used to maintain its temperature. This mechanism facilitates the achievement of very high energy-multiplication factors Q, but also raises a number of new issues of confinement physics. To ensure satisfactory reaction operation, three areas of energetic-ion interaction need to be addressed: single-ion transport in imperfectly symmetric magnetic fields or turbulent background plasmas; energetic-ion-driven (or stabilized) collective phenomena; and fusion-heat-driven collective phenomena. The first of these topics is already being explored in a number of tokamak experiments, and the second will begin to be addressed in the D-T-burning phase of TFTR and JET. Exploration of the third topic calls for high-Q operation, which is a goal of proposed next-generation plasma-burning projects. Planning for future experiments must take into consideration the full range of plasma-physics and engineering R D areas that need to be addressed on the way to a fusion power demonstration.

  18. [Effect of carbachol on intestinal mucosa blood flow and absorption rate of glucose-electrolyte solution during enteral resuscitation for 50% total body surface area full-thickness burn injury in dog].

    PubMed

    Hu, Sen; Che, Jin-wei; Du, Ying; Bao, Cheng-mei; Tian, Yi-jun; Wang, Lei; Geng, Shi-jia; Wu, Jing; Sheng, Zhi-yong

    2008-03-01

    To investigate the effect of carbachol (CAR) on blood flow of intestinal mucosa and absorption rate of glucose-electrolyte solution (GES) during enteral resuscitation of burn shock in dog. Eighteen male Beagle dogs were subjected to a (51.2+/-2.6)% total body surface area (TBSA) full-thickness flame injury, and fluid resuscitation was given according to Parkland formula 0.5 hour after burn. Animals were randomly divided into intravenous infusion of GES group (VGES group, n=6), enteral infusion of GES group (EGES group, n=6) and EGES containing 0.25 microg/kg of CAR group (EGES/CAR group n=6). In the first 8 hours post burn, intestinal absorption rate of water and Na+, intestinal mucosa blood flow (IBF), the plasma volume (PV) and plasma concentration of Na+ were continuously determined without anesthesia. At the end of 8 hours animals were sacrificed, and specimens of gut tissue were taken to determine the activity of Na+-K+-ATPase. The intestinal absorption rate of water and Na+ was reduced markedly after burn in two enteral resuscitation groups and much lower than pre-injury levels and the expected infusing rate according to Parkland formula. It was found that the absorption rate of water and Na+ from 1.5 hours and 2.5 hours in EGES/CAR group were significantly higher compared with those in EGES group (all P<0.05). During 8 hours after burn, only 47.1% and 63.8% of fluids enterally infused in EGES and EGES/CAR groups were absorbed by the gut. The volume of fluid absorbed and the fluid absorption rate were significantly higher in EGES/CAR group than those in EGES group (P<0.05). Incidence of gut intolerance (diarrhea) was 83% in EGES group, which was higher than that of in EGES/CAR group (50%). IBF was significantly decreased compared with pre-injury levels in all groups. Enteral infusion of CAR led to a significant elevation of IBF in EGES/CAR compared with GES group from 4 hours after burn, but it was still lower than pre-injury levels and those in VGES group

  19. A half-century of burn epidemiology and burn care in a rural state.

    PubMed

    Blaisdell, Laura L; Chace, Reeve; Hallagan, Lee D; Clark, David E

    2012-01-01

    The aim of this study is to quantify the changes in incidence, severity, and mortality in burn injuries in the state of Maine over the past 50 years from both prevention and treatment perspectives. The authors analyzed the data from multiple sources, including the U.S. Census, death certificates, hospital discharge abstracts, and institutional burn registries in Maine and Boston. The average annual number of burn-related deaths decreased from 53 in 1960-1964 to 14 in 2004-2008. The Maine age-adjusted rate of burn deaths was 8.6% above the national rate in 1960 and 1.4% below it in 2006. The annual number of burn patients admitted to Maine hospitals declined by 65% from 1978 to 2009. Since 1999, 12% of hospitalized patients in Maine were treated in an American Burn Association-certified burn center in Boston. Mortality for Maine burn patients, including those treated at Boston hospitals, is directly related to age and burn severity and similar to stratified mortality in the National Burn Repository. Incidence, severity, and mortality of burn injuries in Maine have decreased dramatically over the past 5 decades. Prevention programs, legislation, and a regionalized system of burn care have all likely contributed to bringing Maine's morbidity and mortality rate below the national average.

  20. Ram Burn Observations (RAMBO)

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Ram Burn Observations (RAMBO) is a Department of Defense experiment that observes shuttle Orbital Maneuvering System engine burns for the purpose of improving plume models. On STS-107 the appropriate sensors will observe selected rendezvous and orbit adjust burns.

  1. Reduction of Nitrogen Oxide Emissions for lean Burn Engine Technology

    SciTech Connect

    McGill, R.N.

    1998-08-04

    Lean-burn engines offer the potential for significant fuel economy improvements in cars and trucks, perhaps the next great breakthrough in automotive technology that will enable greater savings in imported petroleum. The development of lean-burn engines, however, has been an elusive goal among automakers because of the emissions challenges associated with lead-burn engine technology. Presently, cars operate with sophisticated emissions control systems that require the engine's air-fuel ratio to be carefully controlled around the stoichiometric point (chemically correct mixture). Catalysts in these systems are called "three-way" catalysts because they can reduce hydrocarbon, carbon monoxide, and nitrogen oxide emissions simultaneously, but only because of the tight control of the air-fuel ratio. The purpose of this cooperative effort is to develop advanced catalyst systems, materials, and necessary engine control algorithms for reducing NOX emissions in oxygen-rich automotive exhaust (as with lean-burn engine technology) to meet current and near-future mandated Clean Air Act standards. These developments will represent a breakthrough in both emission control technology and automobile efficiency. The total project is a joint effort among five national laboratories, together with US CAR. The role of Lockheed-Martin Energy Systems in the total project is two fold: characterization of catalyst performance through laboratory evaluations from bench-scale flow reactor tests to engine laboratory tests of full-scale prototype catalysts, and microstructural characterization of catalyst material before and after test stand and/or engine testing.

  2. [High voltage electrical burns as a risk factor for mortality among burn patients].

    PubMed

    Mangelsdorff, Günther; García-Huidobro, M Angélica; Nachari, Isaac; Atenas, Omar; Whittle, Sandra; Villegas, Jorge

    2011-02-01

    Electrical burns are associated with complications and may aggravate burned patients. To evaluate the effect of electrical burns in mortality and length of stay in a critical care unit for burn patients. Retrospective analysis of medical records of 182 patients aged 15 to 90 years, admitted to an intensive care unit for burn patients. The length of stay and mortality of 14 patients that suffered electric burns was compared with the features of 168 patients with other type of burns. Patients with electrical burns were younger, had a lower percentage of total body surface burnt and had a lower frequency of inhalatory injuries than their counterparts with other type of burns. Mortality rate among patients with electric or other types of burns was similar (three and 49 patients, respectively). Intensive care unit stay was also similar. A multivariate analysis showed that high voltage electric burns were an independent risk factor for death with an odds ratio of 12 (95% confidence intervals 1.8-79.4). High voltage electric burns are an independent risk factor for death among burn patients.

  3. Burning Mouth Syndrome and "Burning Mouth Syndrome".

    PubMed

    Rifkind, Jacob Bernard

    2016-03-01

    Burning mouth syndrome is distressing to both the patient and practitioner unable to determine the cause of the patient's symptoms. Burning mouth syndrome is a diagnosis of exclusion, which is used only after nutritional deficiencies, mucosal disease, fungal infections, hormonal disturbances and contact stomatitis have been ruled out. This article will explore the many causes and treatment of patients who present with a chief complaint of "my mouth burns," including symptomatic treatment for those with burning mouth syndrome.

  4. Mechanistic role of water on the rate and selectivity of Fischer-Tropsch synthesis on ruthenium catalysts.

    PubMed

    Hibbitts, David D; Loveless, Brett T; Neurock, Matthew; Iglesia, Enrique

    2013-11-18

    Water increases Fischer-Tropsch synthesis (FTS) rates on Ru through H-shuttling processes. Chemisorbed hydrogen (H*) transfers its electron to the metal and protonates the O-atom of CO* to form COH*, which subsequently hydrogenates to *HCOH* in the kinetically relevant step. H2 O also increases the chain length of FTS products by mediating the H-transfer steps during reactions of alkyl groups with CO* to form longer-chain alkylidynes and OH*. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Photo-oxidation catalysts

    DOEpatents

    Pitts, J. Roland; Liu, Ping; Smith, R. Davis

    2009-07-14

    Photo-oxidation catalysts and methods for cleaning a metal-based catalyst are disclosed. An exemplary catalyst system implementing a photo-oxidation catalyst may comprise a metal-based catalyst, and a photo-oxidation catalyst for cleaning the metal-based catalyst in the presence of light. The exposure to light enables the photo-oxidation catalyst to substantially oxidize absorbed contaminants and reduce accumulation of the contaminants on the metal-based catalyst. Applications are also disclosed.

  6. PILLARED CLAYS AS SUPERIOR CATALYSTS FOR SELECTIVE CATALYTIC REDUCTION OF NITRIC OXIDE

    SciTech Connect

    R.Q. Long; N. Tharappiwattananon; W.B. Li; R.T. Yang

    2000-09-01

    Removal of NO{sub x} (NO + NO{sub 2}) from exhaust gases is a challenging subject. V{sub 2}O{sub 5}-based catalysts are commercial catalysts for selective catalytic reduction (SCR) with NH{sub 3} for stationary sources. However, for diesel and lean-burn gasoline engines in vehicles, hydrocarbons would be the preferred reducing agents over NH{sub 3} because of the practical problems associated with the use of NH{sub 3} (i.e., handling and slippage through the reactor). The noble-metal three-way catalysts are not effective under these conditions. The first catalyst found to be active for selective catalytic reduction of NO by hydrocarbons in the presence of excess oxygen was copper exchanged ZSM-5 and other zeolites, reported in 1990 by Iwamoto in Japan and Held et al. in Germany. Although Cu-ZSM-5 is very active and the most intensively studied catalyst, it suffers from severe deactivation in engine tests, mainly due to H{sub 2}O and SO{sub 2}. In this project, we found that ion-exchanged pillared clays and MCM-41 catalysts showed superior SCR activities of NO with hydrocarbon. All Cu{sup 2+}-exchanged pillared clays showed higher SCR activities than Cu-ZSM-5 reported in the literature. In particular, H{sub 2}O and SO{sub 2} only slightly deactivated the SCR activity of Cu-TiO{sub 2}-PILC, whereas severe deactivation was observed for Cu-ZSM-5. Moreover, Pt/MCM-41 provided the highest specific NO reduction rates as compared with other Pt doped catalysts, i.e., Pt/Al{sub 2}O{sub 3}, Pt/SiO{sub 2} and Pt/ZSM-5. The Pt/MCM-41 catalyst also showed a good stability in the presence of H{sub 2}O and SO{sub 2}.

  7. Pediatric burns in Mosul: an epidemiological study.

    PubMed

    Al-Zacko, S M; Zubeer, H G; Mohammad, A S

    2014-06-30

    A cross-sectional study was conducted to determine the characteristics and case fatality rate of pediatric burns in Mosul, Iraq. The study group was burn patients aged 14 years and under who were admitted to the Burns Unit in Al-Jamhoori Teaching Hospital from the 1(st) of March 2011 to the 1(st) of March 2012. Of the 459 emergency burn admissions, 209 (45.53%) were pediatric patients up to 14 years of age, with a mean age of 4.73±3.61 years. Scald was the most common type of burn and occurred mainly in domestic settings. The mean total body surface area (TBSA) burned was 19.73±17.15%. Thirty-five patients died during the study period, giving a case fatality rate of 16.75%. The maximum number of deaths occurred in the 2-4 years age group. The case fatality rate was high in patients having more than 40% TBSA involvement. Flame burns were significantly more fatal than scalds, with a fatality rate of 35.35% and 12.05% respectively; (p=0.0001). In conclusion, given that most pediatric burn accidents occur at home, burn prevention should be focused on improving living conditions and on providing an educational program for parents.

  8. A molecular copper catalyst for electrochemical water reduction with a large hydrogen-generation rate constant in aqueous solution.

    PubMed

    Zhang, Peili; Wang, Mei; Yang, Yong; Yao, Tianyi; Sun, Licheng

    2014-12-08

    The copper complex [(bztpen)Cu](BF4)2 (bztpen=N-benzyl-N,N',N'-tris(pyridin-2-ylmethyl)ethylenediamine) displays high catalytic activity for electrochemical proton reduction in acidic aqueous solutions, with a calculated hydrogen-generation rate constant (k(obs)) of over 10000 s(-1). A turnover frequency (TOF) of 7000 h(-1) cm(-2) and a Faradaic efficiency of 96% were obtained from a controlled potential electrolysis (CPE) experiment with [(bztpen)Cu](2+) in pH 2.5 buffer solution at -0.90 V versus the standard hydrogen electrode (SHE) over two hours using a glassy carbon electrode. A mechanism involving two proton-coupled reduction steps was proposed for the dihydrogen generation reaction catalyzed by [(bztpen)Cu](2+).

  9. Partial Oxidation of Hydrocarbons in a Segmented Bed Using Oxide-based Catalysts and Oxygen-conducting Supports

    NASA Astrophysics Data System (ADS)

    Smith, Mark W.

    reactor inlet, followed by a reforming catalyst. This approach demonstrated that BNHA can be used in the reactor inlet to promote combustion with 1 wt% Rh-substituted pyrochlore in the reactor outlet, but the combustion catalyst should fill less than 50% of the reactor. The second approach placed specific catalysts in regions of the reactor that have conditions in which they are less likely to deactivate. This showed the most benefit in the use of a sulfur-tolerant noble metal catalyst in the reactor outlet. The carbon formation study was conducted on a 2 wt% Rh-substituted pyrochlore. POX of TD for various run times, followed by temperature programmed oxidation, revealed two different types of carbon deposits in the catalyst bed: carbon that burned off at relatively low temperature (LTC), and carbon that burned off at higher temperatures (HTC). The LTC reached a steady state level within two hours of reaction, and was determined not to lead to catalyst deactivation. The HTC continued to accumulate with time on stream. A mathematical expression was developed to predict the rate of formation of the HTC for a given set of reaction conditions (O/C = 1.25). This expression was modified from data from a test under different reaction conditions (O/C = 1.1) for one length of time, and was found to predict the carbon formation for a different run time within 3%.

  10. Exhaust gas purification system for lean burn engine

    DOEpatents

    Haines, Leland Milburn

    2002-02-19

    An exhaust gas purification system for a lean burn engine includes a thermal mass unit and a NO.sub.x conversion catalyst unit downstream of the thermal mass unit. The NO.sub.x conversion catalyst unit includes at least one catalyst section. Each catalyst section includes a catalytic layer for converting NO.sub.x coupled to a heat exchanger. The heat exchanger portion of the catalyst section acts to maintain the catalytic layer substantially at a desired temperature and cools the exhaust gas flowing from the catalytic layer into the next catalytic section in the series. In a further aspect of the invention, the exhaust gas purification system includes a dual length exhaust pipe upstream of the NO.sub.x conversion catalyst unit. The dual length exhaust pipe includes a second heat exchanger which functions to maintain the temperature of the exhaust gas flowing into the thermal mass downstream near a desired average temperature.

  11. Burning mouth syndrome.

    PubMed

    Crow, Heidi C; Gonzalez, Yoly

    2013-02-01

    Pain in the tongue or oral tissues described as "burning" has been referred to by many terms including burning mouth syndrome. When a burning sensation in the mouth is caused by local or systemic factors, it is called secondary burning mouth syndrome and when these factors are treated the pain will resolve. When burning mouth syndrome occurs in the absence of identified risk indicators, the term primary burning mouth syndrome is utilized. This article focuses on descriptions, etiologic theories, and management of primary burning mouth syndrome, a condition for which underlying causative agents have been ruled out.

  12. Highly dispersed metal catalyst

    DOEpatents

    Xiao, Xin; West, William L.; Rhodes, William D.

    2016-11-08

    A supported catalyst having an atomic level single atom structure is provided such that substantially all the catalyst is available for catalytic function. A process of forming a single atom catalyst unto a porous catalyst support is also provided.

  13. Reforming catalyst

    SciTech Connect

    Baird, W.C. Jr.; Swan, G.A.

    1991-11-19

    This patent describes a catalyst useful for reforming a naphtha feed at high severity reforming conditions. It comprises the metals, platinum, rhenium and iridium on a refractory porous inorganic oxide support, the support consisting essentially of alumina, wherein the concentration by weight of each of the metals platinum and rhenium is at least 0.1 percent and iridium at least 0.15 percent and at least one of the metals is present in a concentration of at least 0.3 percent, and the sum-total; concentration of the metals is greater than 0.9 percent, and wherein each catalyst particle contains all three of the metals platinum, rhenium and iridium. This patent also describes this composition wherein the catalyst contains from about 0.1 percent to about 3 percent of a halogen and from about 0.05 percent to about 0.02 percent sulfur.

  14. Muscle Contractile Properties in Severely Burned Rats

    PubMed Central

    Wu, Xiaowu; Wolf, Steven E.; Walters, Thomas J.

    2010-01-01

    Burn induces a sustained catabolic response which causes massive loss of muscle mass after injury. A better understanding of the dynamics of muscle wasting and its impact on muscle function is necessary for the development of effective treatments. Male Sprague-Dawley rats underwent either a 40% total body surface area (TBSA) scald burn or sham burn, and were further assigned to subgroups at four time points after injury (days 3, 7, 14 and 21). In situ isometric contractile properties were measured including twitch tension (Pt), tetanic tension (Po) and fatigue properties. Body weight decreased in burn and sham groups through day 3, however, body weight in the sham groups recovered and increased over time compared to burned groups, which progressively decreased until day 21 after injury. Significant differences in muscle wet weight and protein weight were found between sham and burn. Significant differences in muscle contractile properties were found at day 14 with lower absolute Po as well as specific Po in burned rats compared to sham. After burn, the muscle twitch tension was significantly higher than the sham at day 21. No significant difference in fatigue properties was found between the groups. This study demonstrates dynamics of muscle atrophy and muscle contractile properties after severe burn; this understanding will aid in the development of approaches designed to reduce the rate and extent of burn induced muscle loss and function. PMID:20381255

  15. Advanced liquefaction using coal swelling and catalyst dispersion techniques. Quarterly technical progress report No. 7, April 1993--June 1993

    SciTech Connect

    Curtis, C.W.; Chander, S.; Gutterman, C.

    1994-09-01

    The overall objective of this project is to develop a new approach for the direct liquefaction of coal to produce an all-distillate product slate at a sizable cost reduction over current technology. The approach integrates coal selection, pretreatment, coal swelling with catalyst impregnation, liquefaction, product recovery with characterization, alternate bottoms processing, and carrying out a technical assessment including an economic evaluation. The project is being carried out under contract to the United States Department of Energy. All three coals used in this study (Black Thunder, Burning Star bituminous, and Martin Lake lignite) are effectively swelled by a number of solvents. The most effective solvents are those having hetero-functionality. In addition, a synergistic effect has been demonstrated, in which solvent blends are more effective for coal swelling than the pure solvents alone. Therefore, it will be necessary to use only low levels of swelling agents and yet promote the impregnation of catalyst precursors. The rate of the impregnation of catalyst precursors into swollen coal increases greatly as the effectiveness of the solvent to swell the coal increases. This effect is also demonstrated by improved catalyst precursor impregnation with increased contact temperature. Laboratory- and bench-scale liquefaction experimentation is underway using swelled and catalyst impregnated coal samples. Higher coal conversions were observed for the SO{sub 2}-treated coal than the raw coal, regardless of catalyst type. Conversions of swelled coal were highest when Molyvan-L, molybdenum naphthenate, and nickel octoate, respectively, were added to the liquefaction solvent.

  16. Features identification for automatic burn classification.

    PubMed

    Serrano, Carmen; Boloix-Tortosa, Rafael; Gómez-Cía, Tomás; Acha, Begoña

    2015-12-01

    In this paper an automatic system to diagnose burn depths based on colour digital photographs is presented. There is a low success rate in the determination of burn depth for inexperienced surgeons (around 50%), which rises to the range from 64 to 76% for experienced surgeons. In order to establish the first treatment, which is crucial for the patient evolution, the determination of the burn depth is one of the main steps. As the cost of maintaining a Burn Unit is very high, it would be desirable to have an automatic system to give a first assessment in local medical centres or at the emergency, where there is a lack of specialists. To this aim a psychophysical experiment to determine the physical characteristics that physicians employ to diagnose a burn depth is described. A Multidimensional Scaling Analysis (MDS) is then applied to the data obtained from the experiment in order to identify these physical features. Subsequently, these characteristics are translated into mathematical features. Finally, via a classifier (Support Vector Machine) and a feature selection method, the discriminant power of these mathematical features to distinguish among burn depths is analysed, and the subset of features that better estimates the burn depth is selected. A success rate of 79.73% was obtained when burns were classified as those which needed grafts and those which did not. Results validate the ability of the features extracted from the psychophysical experiment to classify burns into their depths. Copyright © 2015 Elsevier Ltd and ISBI. All rights reserved.

  17. Satisfaction with life after burn: A Burn Model System National Database Study.

    PubMed

    Goverman, J; Mathews, K; Nadler, D; Henderson, E; McMullen, K; Herndon, D; Meyer, W; Fauerbach, J A; Wiechman, S; Carrougher, G; Ryan, C M; Schneider, J C

    2016-08-01

    While mortality rates after burn are low, physical and psychosocial impairments are common. Clinical research is focusing on reducing morbidity and optimizing quality of life. This study examines self-reported Satisfaction With Life Scale scores in a longitudinal, multicenter cohort of survivors of major burns. Risk factors associated with Satisfaction With Life Scale scores are identified. Data from the National Institute on Disability, Independent Living, and Rehabilitation Research (NIDILRR) Burn Model System (BMS) database for burn survivors greater than 9 years of age, from 1994 to 2014, were analyzed. Demographic and medical data were collected on each subject. The primary outcome measures were the individual items and total Satisfaction With Life Scale (SWLS) scores at time of hospital discharge (pre-burn recall period) and 6, 12, and 24 months after burn. The SWLS is a validated 5-item instrument with items rated on a 1-7 Likert scale. The differences in scores over time were determined and scores for burn survivors were also compared to a non-burn, healthy population. Step-wise regression analysis was performed to determine predictors of SWLS scores at different time intervals. The SWLS was completed at time of discharge (1129 patients), 6 months after burn (1231 patients), 12 months after burn (1123 patients), and 24 months after burn (959 patients). There were no statistically significant differences between these groups in terms of medical or injury demographics. The majority of the population was Caucasian (62.9%) and male (72.6%), with a mean TBSA burned of 22.3%. Mean total SWLS scores for burn survivors were unchanged and significantly below that of a non-burn population at all examined time points after burn. Although the mean SWLS score was unchanged over time, a large number of subjects demonstrated improvement or decrement of at least one SWLS category. Gender, TBSA burned, LOS, and school status were associated with SWLS scores at 6 months

  18. How Does the Freezer Burn Our Food?

    ERIC Educational Resources Information Center

    Schmidt, Shelly J.; Lee, Joo Won

    2009-01-01

    Freezer burn is a common problem that significantly affects the color, texture, and flavor of frozen foods. Food science students should be able to clearly explain the causes and consequences of freezer burn. However, it is difficult to find a modern, detailed, accurate, yet concise, explanation of the mechanism and factors influencing the rate of…

  19. Equations for Composite-Propellant Burning

    NASA Technical Reports Server (NTRS)

    Strand, L. D.; Cohen, N. S.

    1983-01-01

    Reported study of composite-propellant burning summarizes recent advances in understanding behavior of propellant formulations based on ammonium perchlorate (AOP), binder, and aluminum in various proportions and particle size distributions. Approach presented incorporates adapted version of earlier model for monopropellant AP. Objective is to predict burning-rate characteristics of composite propellants at high pressure.

  20. How Does the Freezer Burn Our Food?

    ERIC Educational Resources Information Center

    Schmidt, Shelly J.; Lee, Joo Won

    2009-01-01

    Freezer burn is a common problem that significantly affects the color, texture, and flavor of frozen foods. Food science students should be able to clearly explain the causes and consequences of freezer burn. However, it is difficult to find a modern, detailed, accurate, yet concise, explanation of the mechanism and factors influencing the rate of…

  1. Emotional associations with skin: differences between burned and non-burned individuals.

    PubMed

    Titscher, A; Lumenta, D B; Kamolz, L P; Mittlboeck, M; Frey, M

    2010-09-01

    The appearance of skin is crucial for our physical and psychological integrity, and is strongly associated with our emotional self-awareness. Burn victims have to cope with negative and even threatening sensations resulting from the changed appearance of their skin after injury and also linked to experiences during the treatment. The aim of this study was to analyse differences regarding the emotional associations with skin in burn victims (burn group) to persons not having subdued any burn (control group). In the first instance over 960 volunteers were recruited for the rating of emotional associations with skin in the control group and thereby a representative profile for non-injured individuals. In the second part, 44 burn patients of the Vienna Burn Center answered the same questionnaire. The quantitative rating of emotional associations with skin was performed with a newly designed questionnaire using a semantic differential on eight dimensions with a 5-point scale system. Both groups have positive associations with skin. One significant difference (p=0.0090, Chi-square test for trend) was the overall rating of the item "importance": for burn victims skin is more "important" than for controls. Patients with visible burns tended to put more emphasize on the possible exposure to danger ("threatened") of skin, and patients with >/=20% TBSA rated skin as more "noticeable" and "strong" as compared to small burns (<20% TBSA). Patients with burns to the face, hands and neck ("visible burns") were more likely to judge skin as threatened item. Our poll suggests that despite long treatment, rehabilitation and even near-death experiences burn patients continue to have positive associations with skin. This in turn, should encourage all specialists dealing with burns to engage in a continuous follow-up as well as enhance psychological and social support. 2010 Elsevier Ltd and ISBI. All rights reserved.

  2. Antiseptics for burns.

    PubMed

    Norman, Gill; Christie, Janice; Liu, Zhenmi; Westby, Maggie J; Jefferies, Jayne M; Hudson, Thomas; Edwards, Jacky; Mohapatra, Devi Prasad; Hassan, Ibrahim A; Dumville, Jo C

    2017-07-12

    -antibacterial treatment or another antiseptic. Most evidence was assessed as low or very low certainty, often because of imprecision resulting from few participants, low event rates, or both, often in single studies. Antiseptics versus topical antibioticsCompared with the topical antibiotic, SSD, there is low certainty evidence that, on average, there is no clear difference in the hazard of healing (chance of healing over time), between silver-based antiseptics and SSD (HR 1.25, 95% CI 0.94 to 1.67; I(2) = 0%; 3 studies; 259 participants); silver-based antiseptics may, on average, increase the number of healing events over 21 or 28 days' follow-up (RR 1.17 95% CI 1.00 to 1.37; I(2) = 45%; 5 studies; 408 participants) and may, on average, reduce mean time to healing (difference in means -3.33 days; 95% CI -4.96 to -1.70; I(2) = 87%; 10 studies; 979 participants).There is moderate certainty evidence that, on average, burns treated with honey are probably more likely to heal over time compared with topical antibiotics (HR 2.45, 95% CI 1.71 to 3.52; I(2) = 66%; 5 studies; 140 participants).There is low certainty evidence from single trials that sodium hypochlorite may, on average, slightly reduce mean time to healing compared with SSD (difference in means -2.10 days, 95% CI -3.87 to -0.33, 10 participants (20 burns)) as may merbromin compared with zinc sulfadiazine (difference in means -3.48 days, 95% CI -6.85 to -0.11, 50 relevant participants). Other comparisons with low or very low certainty evidence did not find clear differences between groups.Most comparisons did not report data on infection. Based on the available data we cannot be certain if antiseptic treatments increase or reduce the risk of infection compared with topical antibiotics (very low certainty evidence). Antiseptics versus alternative antisepticsThere may be some reduction in mean time to healing for wounds treated with povidone iodine compared with chlorhexidine (MD -2.21 days, 95% CI 0.34 to 4.08). Other evidence

  3. Epidemiology of paediatric burns in Iran.

    PubMed

    Karimi, H; Montevalian, A; Motabar, A R; Safari, R; Parvas, M S; Vasigh, M

    2012-09-30

    We surveyed the epidemiology of the patients in a tertiary burn care centre (the Motahari Burn Hospital) in Tehran in the 4-yr period 2005-2009. Scalding was the major cause of burn injury for patients under the age of 6, while there were many more flame and electrical burns in late childhood. Males were mainly affected (male to female ratio, 1.7:1). Most burns occurred in the summer, probably due to older children's increased outdoor activities during school vacations. Most of the injuries took place in the kitchen. Age was directly related to the higher total body surface area and mortality rate. Explosion of propane gas at home had a high incidence. Length of hospital stay increased in relation to the burn surface area. Infants were found to be at greatest risk for burn injuries, while older children were at higher risk for severe burns. Before arriving at the hospital, 22 patients had received traditional therapy in the home which was not effective and caused some problems. Pre-hospital care by emergency medicine service personnel was complete and effective. 374 patients had positive results for wound culture (42.9%). The most frequent bacteria found in burn wound cultures was coagulase-negative Staphylococcus (66.8%). Blood culture was positive in 12% of the patients with positive burn wound culture and the most frequent bacteria in blood culture was Pseudomonas aeruginosa. The overall mortality rate was 10.6%. Treatment and prevention programmes should target high risk groups. Important criteria include older age, flame burn, presence of inhalation injury, total body surface area burned above 40%, and sepsis.

  4. Catalyst activator

    DOEpatents

    McAdon, Mark H.; Nickias, Peter N.; Marks, Tobin J.; Schwartz, David J.

    2001-01-01

    A catalyst activator particularly adapted for use in the activation of metal complexes of metals of Group 3-10 for polymerization of ethylenically unsaturated polymerizable monomers, especially olefins, comprising two Group 13 metal or metalloid atoms and a ligand structure including at least one bridging group connecting ligands on the two Group 13 metal or metalloid atoms.

  5. Factors affecting the depth of burns occurring in medical institutions.

    PubMed

    Cho, Young Soon; Choi, Young Hwan; Yoon, Cheonjae; You, Je Sung

    2015-05-01

    Most cases of burns occurring in medical institutions are associated with activities involving heat. It is very difficult to detect these burns. To date, there are few reports on burns occurring in medical institutions. The purpose of this paper was to analyze the etiology of burns occurring in medical institutions and to elucidate the factors affecting burn depth. We conducted a retrospective analysis of the medical records of patients who visited our center from April 2008 to February 2013. This study enrolled all patients with burns occurring in the medical institution during or related to treatment. We excluded burn patients whose burns were not related to treatment (for example, we excluded patients with scalding burns that occurred in the hospital cafeteria and pediatric patients with hot water burns from the water purifier). However, patients with burns that occurred in the recovery room after general anesthesia were included. A total of 115 patients were enrolled in this study. The average patient age was 41.5 years, with more women than men (M:F=31:84). There were 29 cases (25.3%) of superficial burns (first-degree and superficial second-degree) and 86 cases (74.7%) of deep burns (deep second-degree and third-degree). Hot packs were the most common cause of burns (27 cases, 23.5%), followed by laser therapy, heating pads, and grounding pads, accounting for 15 cases each. There were 89 cases (77.4%) of contact burns and 26 cases (22.6%) of non-contact burns. The most common site of burns was the lower extremities (41 cases, 35.7%). The burn site and contact burns were both factors affecting burn depth. The rate of deep burns was higher in patients with contact burns than in those with non-contact burns (odds ratio 4.26) and was associated with lower body burns (odds ratio 2.85). In burns occurring in medical institutions, there is a high probability of a deep burn if it is a contact burn or occurs in the lower body. Therefore, safety guidelines are needed

  6. Analysis of hospitalized burned patients in bandar abbass, iran.

    PubMed

    Hasani, L; Aghamolei, T; Boushehri, E; Sabili, A

    2009-06-28

    This study was conducted to determine the causes and outcomes of burn in patients referred to Shahid Mohammadi Hospital in Bandar Abbass, southern Iran, in which 212 burned patients were assessed from March 2007 to March 2008 .Mean age of patients was 22.14 yr. Heat contact was the main cause of burn with 92.5%. 49.1% of total burns occurred among less than 20 yr old people. Mortality rate was 10.4%. Most of burns occurred at home. An educational program is necessary to prevent thermal burning at home.

  7. In situ burning of oil spills: Mesoscale experiments

    SciTech Connect

    Walton, W.D.

    1993-11-01

    In 1991 a series of 14 mesoscale fire experiments were performed to measure the burning characteristics of crude oil on salt water. These oil burns in a pan ranged in size from 6 m square to 15 m square. Results of the measurements for burning rate, oil temperature, water temperature, smoke particle size distribution, smoke plume trajectory, and smoke particulate yield are provided. The burning rate as indicated by the regression rate of the oil surface was found to be 0.055 (+ or -) 0.005 mm/s and smoke particulate yields were found to be approximately 0.13 of the oil burned on a mass basis.

  8. Mixed Convection Blowoff Limits as a Function of Oxygen Concentration and Upward Forced Stretch Rate for Burning Pmma Rods of Various Sizes

    NASA Technical Reports Server (NTRS)

    Marcum, Jeremy W.; Ferkul, Paul V.; Olson, Sandra L.

    2017-01-01

    Normal gravity flame blowoff limits in an axisymmetric pmma rod geometry in upward axial stagnation flow are compared with microgravity Burning and Suppression of Solids II (BASS-II) results recently obtained aboard the International Space Station. This testing utilized the same BASS-II concurrent rod geometry, but with the addition of normal gravity buoyant flow. Cast polymethylmethacrylate (pmma) rods of diameters ranging from 0.635 cm to 3.81 cm were burned at oxygen concentrations ranging from 14 to 18 by volume. The forced flow velocity where blowoff occurred was determined for each rod size and oxygen concentration. These blowoff limits compare favorably with the BASS-II results when the buoyant stretch is included and the flow is corrected by considering the blockage factor of the fuel. From these results, the normal gravity blowoff boundary for this axisymmetric rod geometry is determined to be linear, with oxygen concentration directly proportional to flow speed. We describe a new normal gravity upward flame spread test method which extrapolates the linear blowoff boundary to the zero stretch limit to resolve microgravity flammability limits, something current methods cannot do. This new test method can improve spacecraft fire safety for future exploration missions by providing a tractable way to obtain good estimates of material flammability in low gravity.

  9. LA50 in burn injuries.

    PubMed

    Seyed-Forootan, K; Karimi, H; Motevalian, S A; Momeni, M; Safari, R; Ghadarjani, M

    2016-03-31

    Burn injuries put a huge financial burden on patients and healthcare systems. They are the 8th leading cause of mortality and the 13th most common cause of morbidity in our country. We used data from our Burn Registry Program to evaluate risk factors for mortality and lethal area fifty percent (LA50) in all burn patients admitted over two years. We used multiple logistic regressions to identify risk factors for mortality. LA50 is a reliable aggregate index for hospital care quality and a good measure for comparing results, also with those of other countries. 28,690 burn patients sought medical attention in the Emergency Department, and 1721 of them were admitted. Male to female ratio was 1,75:1. 514 patients were under 15 years old. Median age was 25 (range: 3 months - 93 years). Overall, probability of death was 8.4%. LA50 was 62.31% (CI 95%: 56.57-70.02) for patients aged 15 and over and 72.52% (CI 95%: 61.01-100) for those under 15. In the final model, we found that Adjusted OR was significant for age, female sex, TBSA and inhalation injury (P < 0.05). LA50 values showed that children tolerate more extensive burns. Female sex, burn size, age and inhalation injury were the main risk factors for death. Authorities should pay special attention to these variables, especially in prevention programs, to reduce mortality and improve patient outcome. Children have better outcome than adults given equal burn size. Suicide rates are higher for women than men in our country.

  10. LA50 in burn injuries

    PubMed Central

    Seyed-Forootan, K.; Karimi, H.; Motevalian, S.A.; Momeni, M.; Safari, R.; Ghadarjani, M.

    2016-01-01

    Summary Burn injuries put a huge financial burden on patients and healthcare systems. They are the 8th leading cause of mortality and the 13th most common cause of morbidity in our country. We used data from our Burn Registry Program to evaluate risk factors for mortality and lethal area fifty percent (LA50) in all burn patients admitted over two years. We used multiple logistic regressions to identify risk factors for mortality. LA50 is a reliable aggregate index for hospital care quality and a good measure for comparing results, also with those of other countries. 28,690 burn patients sought medical attention in the Emergency Department, and 1721 of them were admitted. Male to female ratio was 1,75:1. 514 patients were under 15 years old. Median age was 25 (range: 3 months – 93 years). Overall, probability of death was 8.4%. LA50 was 62.31% (CI 95%: 56.57-70.02) for patients aged 15 and over and 72.52% (CI 95%: 61.01-100) for those under 15. In the final model, we found that Adjusted OR was significant for age, female sex, TBSA and inhalation injury (P < 0.05). LA50 values showed that children tolerate more extensive burns. Female sex, burn size, age and inhalation injury were the main risk factors for death. Authorities should pay special attention to these variables, especially in prevention programs, to reduce mortality and improve patient outcome. Children have better outcome than adults given equal burn size. Suicide rates are higher for women than men in our country PMID:27857645

  11. The promoter effect and a rate expression of the catalytic incineration of (CH3)2S2 over an improved CuO-MoO3/gamma-Al2O3 catalyst.

    PubMed

    Wang, Ching-Huei; Lin, Shiow-Shyung; Liou, Shen-Ben; Weng, Hung-Shan

    2002-10-01

    The CuO-MoO3/gamma-Al2O3 catalyst, confirmed previously as having good activity in the catalytic incineration of (CH3)2S2, was employed as the principal catalyst in this study. With the aim of improving catalyst activity and resistance to deactivation by sulfur compounds, a promoter was added either before adding the precursors of Cu and Mo or together with Cu and Mo onto the gamma-Al2O3. Promoters included transition metals and elements from groups IA-VIIA in the chemical periodic table. Experimental results reveal Cr2O3 as the most effective promoter, with an optimal composition of 5 wt.% Cu, 6 wt.% Mo and 4 wt.% Cr (designated as Cu(5)-Mo(6)-Cr(4)/gamma-Al2O3). Knowing that higher acidity can improve activity, we further investigated the effect of acid treatment on the performance of the Cu(5)-Mo(6)-Cr(4)/gamma-Al2O3 catalyst. Experimental results indicate the H2SO4-treated catalyst (Cu(5)-Mo(6)-Cr(4)/sulfated-gamma-Al2O3) has a better activity and durability. A study for finding an appropriate rate expression for the catalytic incineration of (CH3)2S2 by Cu(5)-Mo(6)-Cr(4)/sulfated-gamma-Al2O3 was carried out in a differential reactor. The results show that the Mars-Van Krevelen model is applicable to this destructive oxidation reaction. Results additionally reveal that competitive adsorption of CH4 reduces conversion of (CH3)2S2.

  12. Epidemiology and Outcomes of Auricular Burn Injuries.

    PubMed

    Kraenzlin, Franca; Mushin, Oren; Ayazi, Shahin; Loree, John; Bell, Derek E

    2017-05-23

    Auricular burns represent a unique type of injury. The acute management and clinical course of these injuries can be different from other facial burns. There is a paucity of literature pertaining to the epidemiology and acute management of auricular burns. Most studies focus on deformity reconstruction. The aim of this study was to characterize the epidemiology, treatment, and outcomes of auricular burns. Data from all patients presenting to a regional burn center in a 4-year period were reviewed and those with auricular burns were identified. Demographic data, burn mechanism, insurance status, method of treatment, need for skin grafting, percentage graft-take, time to reepithelialization and incidence of deformity were reviewed. During the study period, 593 facial burns were evaluated and 132 (22%) sustained burns to the auricle. The most common mechanisms of injury were flame (65.1%) and scalding (22.5%). Auricular burns were mostly second degree (88%), involved both ears in 44%, and involved only the ventral aspect of the ear in 57%. The majority of patients healed well with conservative management; none suffered from chondritis. Of the 89 patients followed to healing, 1 patient (1.1%) received full-thickness skin grafts to the auricle, resulting in excellent graft-take. All other patients were managed nonoperatively, and none suffered from ear deformities. Auricular burns occur with surprising frequency in patients presenting to burn centers. Careful acute management of these injuries can eliminate development of chondritis and minimize the rate of deformity and need for reconstruction. The majority of wounds heal with conservative management, but time to reepithelialization can be prolonged.

  13. [Burns--risk factors and treatment].

    PubMed

    Perry, Zvi H; Palivatkel, Meirav; Yanculewitch, Noam; Koren, Lior; Rosenberg, Nir

    2009-06-01

    Burn injuries are very frequent and afflict approximately 1% of the population yearly. They are a source of heavy medical burden to medical systems worldwide. In the US alone, about 2 million burns are treated by medical staff yearly, and about 75,000 burns are serious enough to require hospitalization. In the UK, a similar situation is depicted in the statistics--burns constitute 1% of the ER workload, and 0.014% of the hospitalization. Morbidity and mortality from burns is mainly dependent upon: total body surface area (TBSA) that is involved in the burn, the depth of the burn and it's anatomical location, the age of the subject, prior medical history and the severity of adjacent injuries (especially pulmonological injury). TBSA is calculated by age-adjusted tables. There are a number of ways to determine this parameter, the simplest of all is called "the rule of 1/9". Using this technique we divide the body into distinct areas, each equal to 1/9 of the TBSA. The treatment of burn injuries is considered one of the most difficult in the medical profession and some even compare it to the treatment of ICU patients. The primary treatment in burns always involves the removal of the patient from the source of the thermal injury, securing his airway (especially in patients suspected of inhalation injury) and an aggressive fluid resuscitation. Fluid resuscitation is mainly managed using the Parkland equation. The treatment of the burned skin is by one of two regimes--the conservative regime (frequent redressing of the burn site, hygiene and antimicrobial treatment) and the surgical regime (early intervention with debridement, skin implantations etc.). Several different studies have shown a decrease in the mortality rate of severe burn patients who have undergone an early surgical regime in comparison to conservative treatment.

  14. Scheduling prescribed burns for hazard reduction in the southeast

    Treesearch

    Stephen S. Sackett

    1975-01-01

    Twelve-year studies in the southeastern Coastal Plain revealed that pine stands should be burned every three years to reduce natural fuels and thus forestall damage from possible wildfires. Rates of overstory growth were not significantly different in burned and unburned stands. Guidelines for prescribed burning of pine stands in this region are presented.

  15. Childhood burns in Israel: a 7-year epidemiological review.

    PubMed

    Goldman, Sharon; Aharonson-Daniel, Limor; Peleg, Kobi

    2006-06-01

    Understanding the etiology of severe burns injuries and identifying high risk groups are essential for allotting resources for prevention and treatment. The objective of this study was to develop a profile of severe childhood burns in Israel. A retrospective study of children (ages 0-14) hospitalized with a burn, between 1998 and 2004. Data from all five burn units in Israel was retrieved from the National Trauma Registry. Two thousand seven hundred and five children were hospitalized with burns (51% of all burn admissions). Infants (ages 0-1) had the highest prevalence (45%). Scalds caused 68% of burns. Burn extent in 83% of the patients was less than 20% TBSA, 3% suffered 40%TBSA burns. Surgical intervention increased from 6% in 1998 to 21% in 2002. Non-Jewish children sustained proportionally more burn injuries (48%). Among Jewish children an increase in burn injuries was noted on Thursdays and Fridays. Infants, boys and non-Jewish children were found to be at greatest risk for a burn injury, while older children were at higher risk for severe burns. Prevention programs should target these high risk groups, with an emphasis on the unique characteristics of each group. Policy makers should reassess the benefits of a pediatric burn unit in Israel. The increase in rates of surgical intervention should be further investigated.

  16. Burn Wise - Partners

    EPA Pesticide Factsheets

    Within this site you will find information for consumers to make informed decisions about what it means to burn wise. And partners will learn about how they can work with EPA to bring cleaner-burning appliances to market.

  17. First Aid: Burns

    MedlinePlus

    ... MORE ON THIS TOPIC Kitchen: Household Safety Checklist Fireworks Safety First Aid: Sunburn Firesetting Fire Safety Burns ... Being Safe in the Kitchen Finding Out About Fireworks Safety Playing With Fire? Dealing With Burns Fireworks ...

  18. Minor burns - aftercare

    MedlinePlus

    ... all clothes that have the chemical on them. Cool the burn: Use cool water, not ice. The extreme cold from ice ... caused by chemicals, hold the burned skin under cool running water for 10 to 15 minutes until ...

  19. Burning and Burnout.

    ERIC Educational Resources Information Center

    Christensen, Jane

    1981-01-01

    Examines the extended metaphor of "burnout" as it applies to the teaching profession. Examines three ancient Celtic invocations for the better tending of fires, which reveal ways that teachers can burn with enthusiasm without burning out from apathy. (RL)

  20. Burn Wise Funding

    EPA Pesticide Factsheets

    EPA is working with federal, state, tribal and local agencies to find and promote viable funding options to replace wood-burning appliances with cleaner home heating. Includes Guide to Financing Options for Wood-burning Appliance Changeouts.

  1. First Aid: Burns

    MedlinePlus

    ... MORE ON THIS TOPIC Kitchen: Household Safety Checklist Fireworks Safety First Aid: Sunburn Firesetting Fire Safety Burns ... Being Safe in the Kitchen Finding Out About Fireworks Safety Playing With Fire? Dealing With Burns Fireworks ...

  2. American Burn Association

    MedlinePlus

    ... on the Journal's website MONTHLY HEADLINES from MSKTC (Model Systems Knowledge Translation Center) The American Burn Association Web site contains general information for burn care professionals. The ABA Web site is not intended ...

  3. Burns - Multiple Languages

    MedlinePlus

    ... Supplements Videos & Tools You Are Here: Home → Multiple Languages → All Health Topics → Burns URL of this page: https://medlineplus.gov/languages/burns.html Other topics A-Z Expand Section ...

  4. Nutrition in Burns: Galveston Contributions

    PubMed Central

    Rodriguez, Noe A.; Jeschke, Marc G.; Williams, Felicia N.; Kamolz, Lars-Peter; Herndon, David N.

    2013-01-01

    Aggressive nutrition support is recommended following severe burn injury. Initially, such injury results in a prolonged and persistent hypermetabolic response mediated by a 10- to 20-fold elevation in plasma catecholamines, cortisol, and inflammatory mediators. This response leads to twice-normal metabolic rates, whole-body catabolism, muscle wasting, and severe cachexia. Thus, it is relevant to review the literature on nutrition in burns to adjust/update treatment. Failure to meet the increased substrate requirements may result in impaired wound healing, multiorgan dysfunction, increased susceptibility to infection, and death. Therefore, aggressive nutrition support is essential to ensure adequate burn care, attenuate the hypermetabolic response, optimize wound healing, minimize devastating catabolism, and reduce morbidity and mortality. Here, the authors provide nutrition recommendations gained from prospective trials, retrospective analyses, and expert opinions based on the authors' practices in Galveston, Texas, and Vienna, Austria. PMID:21975669

  5. Nutrition in burns: Galveston contributions.

    PubMed

    Rodriguez, Noe A; Jeschke, Marc G; Williams, Felicia N; Kamolz, Lars-Peter; Herndon, David N

    2011-11-01

    Aggressive nutrition support is recommended following severe burn injury. Initially, such injury results in a prolonged and persistent hypermetabolic response mediated by a 10- to 20-fold elevation in plasma catecholamines, cortisol, and inflammatory mediators. This response leads to twice-normal metabolic rates, whole-body catabolism, muscle wasting, and severe cachexia. Thus, it is relevant to review the literature on nutrition in burns to adjust/update treatment. Failure to meet the increased substrate requirements may result in impaired wound healing, multiorgan dysfunction, increased susceptibility to infection, and death. Therefore, aggressive nutrition support is essential to ensure adequate burn care, attenuate the hypermetabolic response, optimize wound healing, minimize devastating catabolism, and reduce morbidity and mortality. Here, the authors provide nutrition recommendations gained from prospective trials, retrospective analyses, and expert opinions based on the authors' practices in Galveston, Texas, and Vienna, Austria.

  6. Droplet burning at zero G

    NASA Technical Reports Server (NTRS)

    Williams, F. A.

    1978-01-01

    Questions of the importance and feasibility of performing experiments on droplet burning at zero gravity in Spacelab were studied. Information on the physics and chemistry of droplet combustion, with attention directed specifically to the chemical kinetics, heat and mass transfer, and fluid mechanics of the phenomena involved, are presented. The work was divided into three phases, the justification, the feasibility, and the conceptual development of a preliminary design. Results from the experiments performed revealed a few new facts concerning droplet burning, notably burning rates in excess of theoretical prediction and a phenomenon of flash extinction, both likely traceable to accumulation of carbon produced by gas-phase pyrolysis in the fuel-rich zone enclosed by the reaction surface. These experiments also showed that they were primarily due to timing difficulties.

  7. Treatment of burns in children.

    PubMed

    Herndon, D N; Thompson, P B; Desai, M H; Van Osten, T J

    1985-10-01

    Decreases in mortality from major thermal injury over the last 20 years have been due to advances in resuscitation, control of infection, support of the hypermetabolic response, and early closure of the burn wound. Of these advances in burn care, early wound closure has progressed the most in the last five years. The restoration of the protective functions of the skin is of primary importance to the recovery of the burn patient. Biologic dressings (pigskin, amnion, human skin allograft) when applied to fully debrided, relatively uncontaminated wounds have been shown to adhere to the wound surface, reduce the wound colony counts, limit fluid and protein loss, reduce pain, and increase the rate of epithelialization over that obtained with application of topical antimicrobial agents.

  8. Catalyst suppliers consolidate further, offer more catalysts

    SciTech Connect

    Rhodes, A.K.

    1995-10-02

    The list of suppliers of catalysts to the petroleum refining industry has decreased by five since Oil and Gas Journal`s survey of refining catalysts and catalytic additives was last published. Despite the consolidation, the list of catalyst designations has grown to about 950 in this latest survey, compared to 820 listed in 1993. The table divides the catalysts by use and gives data on their primary differentiating characteristics, feedstock, products, form, bulk density,catalyst support, active agents, availability, and manufactures.

  9. Employment outcomes after burn injury: a comparison of those burned at work and those burned outside of work.

    PubMed

    Schneider, Jeffrey C; Bassi, Sharon; Ryan, Colleen M

    2011-01-01

    This study compares employment rates and barriers to return to work in subjects burned at work with those burned outside of work. Further, this study examines the influence of electrical etiology on return to work outcomes. The electronic records of burn survivors treated at a Regional Burn Center outpatient clinic from 2001 to 2007 were retrospectively reviewed. Inclusion criteria included employment at the time of burn injury and age of 18 years or older. Demographic and medical data were collected. Documentation of barriers to return to work was reviewed and classified into eight categories. Return to employment was grouped into four time intervals: 0 to 3, 3 to 6, 6 to 12, and greater than 12 months after injury. Logistic regression analysis was used to determine predictors of unemployment at greater than 1 year for subjects burned at work, outside of work, and those burned at work without electric injury. The authors identified 197 patients for inclusion in the study. Their age was 37 ± 0.8 years (mean ± SEM), and TBSA burned was 16 ± 1%. Fifty percent of subjects were burned at work. Electric etiology was seen only in those burned at work (n = 24). Forty-four percent (n = 43) of subjects injured at work remained unemployed at 1 year compared with 22% (n = 22) of subjects injured outside of work. The most frequent employment barriers included pain (72%), neurologic problems (62%), and psychiatric problems (53%) for those burned at work; and pain (63%), neurologic problems (59%), and impaired mobility (54%) for those burned outside of work. Significant predictors of unemployment at greater than 12 months included burn at work, pain, impaired mobility, other medical problems, and inpatient rehabilitation (P < .05). When the electrical injury subjects are removed from the analysis, significant predictors of unemployment at 12 months include burn at work, pain, inpatient rehabilitation, and length of stay (P < .05). Burn survivors experience multiple complex

  10. Hydrocracking catalyst

    SciTech Connect

    Arias, B.; Galiasso, R.; Kum, H.

    1985-02-12

    The invention relates to a particular method for the preparation of a hydrocracking catalyst, using a high iron content bauxite as a basis. This bauxite is ground and screened to a specific size and mixed with three types of additives: a promoter additive of the P, Mo, Co, Ni, W type. A hardener additive of the phosphoric acid type, ammonium phosphate. And a lubricant and pore-generating additive of the polyvinyl alcohol, polyethylene-glycol, starch type. The particularity consists in that the three additives are added simultaneously during the extrusion of the sample. That way, a particular surface composition is obtained which allows for the activity of the catalyst. Extruded products are obtained in sizes of 1/8, 1/16, and 1/32'' and submitted to drying and calcination programs for their activation. The obtained catalyst offers a good mechanical strength, a high content in macropores and a high activity, specifically for the hydrocracking of heavy Venezuelan crudes or residues.

  11. Optimization of burn referrals.

    PubMed

    Reiband, Hanna K; Lundin, Kira; Alsbjørn, Bjarne; Sørensen, Anne Marie; Rasmussen, Lars S

    2014-05-01

    Correct estimation of the severity of burns is important to obtain the right treatment of the patient and to avoid over- and undertriage. In this study we aimed to assess how often the guidelines for referral of burn injured patients are met at the national burn centre (NBC), Denmark. We included burn patients referred to the NBC in a three-months period. Patient records were systematically analyzed and compared with the national guidelines for referral of burn injured patients. A total of 97 burn injured patients were transferred for treatment at the NBC and the most common reason for referral was partial thickness burn exceeding 3% estimated area of burn (55% of the patients) while facial burns (32%) and inhalational injury (25%) were other common reasons. We found that 29 (30%) of the referrals were considered potentially unnecessary according to the guidelines. The overtriage was highest among patients suffering of burns due to scalding and these were mostly children below 2 years of age. An overtriage of referred burn injured patient was found and 30% of the referred patients were treated as outpatients. A telemedicine solution may be useful in the evaluation of burn injured patients before transfer. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.

  12. California Burn Scars

    Atmospheric Science Data Center

    2014-05-15

    article title:  Burn Scars Across Southern California     ... California between October 21 and November 18, 2003. Burn scars and vegetation changes wrought by the fires are illustrated in these ... and Nov 18, 2003 Images:  California Burn Scars location:  United States region:  ...

  13. Electric heating pad burns.

    PubMed

    Bill, T J; Edlich, R F; Himel, H N

    1994-01-01

    Patients with sensory deficits are especially prone to heating pad burns. Two cases are reported of patients with anesthetic skin who received partial and full-thickness burns of their feet from an electric heating pad. These burn injuries could have been prevented if the patients understood the potential hazard of heating pads.

  14. Economics of pediatric burns.

    PubMed

    Bass, Michael J; Phillips, Linda G

    2008-07-01

    Sustaining a burn injury sets in motion a cycle of pain, disfigurement, and a search for survival. In pediatric burns, the injury extends to the parents where fear, ignorance, and helplessness forever change their lives. Pediatric burn injuries are caused by fire, hot liquids, clothing irons, hair curlers, caustic substances like drain cleaner, the grounding of an electrical source, and exposure to radiation. Efficiency in the delivery of pediatric burn care is critical. Maximizing resource utilization means continual self-evaluation and economic analysis of therapeutic modalities. Griffiths et al found that most childhood burns are due to scalds, which can be treated for $1061 per percent burn. Paddock et al reduced the cost of treating superficial pediatric burns and reduced the length of stay in hospital using silver-impregnated gauze over traditional methods. Barrett et al found improved cosmesis of skin grafts using cultured epithelial autografts but at a substantially increased cost. Corpron et al showed that pediatric burn units that treat burns >10% total body surface area and operative treatment of pediatric burns regardless of size generate positive revenue. There is a paucity of evidentiary pediatric burn economic data. More research is needed to address areas of pediatric burn care inefficiency. Improving knowledge of cost in all health care endeavors will create competition and drive down expenditures.

  15. Trout Creek 1999 Burn

    Treesearch

    Sherel Goodrich

    2008-01-01

    A small prescribed fire near the mouth of Trout Creek in Strawberry Valley, Wasatch County, Utah, on the Uinta National Forest provided an opportunity to compare production and vascular plant composition in unburned and burned areas. At four years post burn, production of herbaceous plants was about four times greater in the burned area than in the unburned area. Most...

  16. Increased admissions for diabetes mellitus after burn.

    PubMed

    Duke, Janine M; Randall, Sean M; Fear, Mark W; Boyd, James H; O'Halloran, Emily; Rea, Suzanne; Wood, Fiona M

    2016-12-01

    Currently, limited long-term data on hyperglycaemia and insulin sensitivity in burn patients are available and the data that do exist are primarily related to paediatric severe burns. The aim of this study was to assess if burn is associated with increased post-burn admissions for diabetes mellitus. A population-based longitudinal study using linked hospital morbidity and death data from Western Australia was undertaken of all persons hospitalized for a first burn (n=30,997) in 1980-2012 and a frequency matched non-injury comparison cohort, randomly selected from Western Australia's birth registrations and electoral roll (n=123,399). Crude admission rates and summed length of stay for diabetes mellitus were calculated. Negative binomial and Cox proportional hazards regression modelling were used to generate incidence rate ratios (IRR) and hazard ratios (HR), respectively. After adjustment for socio-demographic factors and pre-existing health status, the burn cohort had 2.21 times (95% Confidence Interval (CI): 1.36-1.56) as many admissions and almost three times the number of days in hospital with a diabetes mellitus diagnosis (IRR, 95% CI: 2.94, 2.12-4.09) than the uninjured cohort. Admission rates were significantly elevated for those burned during childhood (<18 years, IRR, 95% CI: 2.65, 1.41-4.97) and adulthood (≥18 years, IRR, 95% CI: 2.12, 1.76-2.55). Incident admissions were significantly elevated in the burn cohort during the first 5 years post-burn when compared with the uninjured (HR, 95% CI: 1.96, 1.46-2.64); no significant difference was found beyond 5 years post-burn (HR, 95% CI: 1.08, 0.82-1.41). Findings of increased hospital admission rates and prolonged length of hospital stay for diabetes mellitus in the burn cohort provide evidence that burns have longer term effects on blood glucose and insulin regulation after wound healing. The first five years after burn discharge appears to be a critical period with significantly elevated incident

  17. Determination of reaction rate constants for phenol oxidation using SnO2/Ti anodes coupled with activated carbon adsorption in the presence of TiO2 as catalyst.

    PubMed

    Zhao, Yuemin; Ding, Yi; Wang, Lizhang; Wang, Xiao

    2011-01-01

    Series of experiments for phenol degradation with assistance of TiO2 catalyst at pH of 6.5 and temperature of 25 degrees C were conducted using a lab-scale electrochemical reactor constructed in our laboratory. According to the results, at the presence of the TiO2 catalyst the removal of phenol was increased and first-order kinetics could describe the evolution of phenol concentration. For inspecting the relationship between rate constants and dosage of TiO2, two possible kinetics were proposed in this study. Contrasted to the abundant experimental data, a reasonable kinetics was obtained for the estimation of phenol concentration effluent during continuous flow of raw wastewater, especially when the TiO2 dosage was less than 0.5g L(-1). The model obtained from these experiments could employed for the calculation of rate constants at different TiO2 dosage and the necessary dosage of catalyst when a discharge standard was designed.

  18. Occupational burns in Washington State, 1989-1993.

    PubMed

    McCullough, J E; Henderson, A K; Kaufman, J D

    1998-12-01

    Occupational burns cause significant morbidity in the United States each year; however, there are few studies that report industries or workplaces where workers are at an increased risk of burn injuries. Washington State's Department of Labor and Industries (L and I) computerized workers' compensation database was used to describe work-related burns over 5 years. From 1989 to 1993, L and I accepted 27,323 claims for occupational burns, 71.4% of them thermal burns and 26.8% chemical burns. The most common sources of injury were cooking oils (14%) and hot water/steam (13%). Workers involved in food preparation or food handling accounted for the highest proportion of injured workers (30%). Industries involved in the smelting, sintering, or refining of ore had the highest rate for thermal burns, with a rate of 15.0 burn injuries per 100 full-time equivalent workers per year, followed by paper, pulp, or wood fiber manufacturing, with a rate of 5.8, then roof work, with a rate of 4.3. Industries involved in hazardous waste landfill clean-up had the highest rate for chemical burns, with a rate of 4.9, followed by portable cleaning and washing, with a rate of 3.5, and paper, pulp, and wood fiber manufacturing, with a rate of 2.6. Further study is needed to identify work practices that result in burn injuries in order to decrease the incidence of this preventable occupational injury.

  19. Epidemiology of burns throughout the World. Part II: intentional burns in adults.

    PubMed

    Peck, Michael D

    2012-08-01

    A significant number of burns and deaths from fire are intentionally wrought. Rates of intentional burns are unevenly distributed throughout the world; India has a particularly high rate in young women whereas in Europe rates are higher in men in mid-life. Data from hospitalized burn patients worldwide reveal incidence rates for assault by fire and scalds ranging from 3% to 10%. The average proportion of the body surface area burned in an assault by fire or scalds is approximately 20%. In different parts of the world, attempted burning of others or oneself can be attributed to different motives. Circumstances under which assaults occur fall largely into the categories of interpersonal conflict, including spousal abuse, elder abuse, or interactions over contentious business transactions. Contributing social factors to assaults by burning include drug and alcohol abuse, non-constructive use of leisure time, non-participation in religious and community activities, unstable relationships, and extramarital affairs. Although the incidence of self-mutilation and suicide attempts by burning are relatively low, deliberate self-harm carries a significant risk of death, with an overall mortality rate of 65% worldwide. In those who resort to self-immolation, circumstantial themes reflect domestic discord, family dysfunction, and the social ramifications of unemployment. Preventing injurious burn-related violence requires a multifaceted approach, including legislation and enforcement, education, and advocacy. Better standardized assessment tools are needed to screen for risks of abuse and for psychiatric disorders in perpetrators. Copyright © 2012 Elsevier Ltd and ISBI. All rights reserved.

  20. Catalyst deactivation in residue hydrocracking

    SciTech Connect

    Oballa, M.C.; Wong, C.; Krzywicki, A.

    1994-12-31

    The existence of a computer-controlled bench scale hydrocracking units at the authors site has made cheaper the non-stop running of experiments for long periods of time. It was, therefore possible to show, at minimal costs, when three hydrocracking catalysts in service reach their maximum lifetime. Different parameters which are helpful for catalyst life and activity predictions were calculated, e.g., relative catalyst age and the effectiveness factor. Experimental results compared well with model, giving them the minimum and maximum catalyst lifetime, as well as the deactivation profile with regard to sulfur and metals removal. Reaction rate constants for demetallization and desulfurization were also determined. Six commercial catalysts were evaluated at short term runs and the three most active were used for long term runs. Out of three catalysts tested for deactivation at long term runs, it was possible to choose one whose useful life was higher than the others. All runs were carried out in a Robinson-Mahoney continuous flow stirred tank reactor, using 50/50 volumetric mixture of Cold Lake/Lloydminster atmospheric residue and NiMo/Al{sub 2}O{sub 3} catalyst.

  1. Combination of best promoter and micellar catalyst for more than kilo-fold rate acceleration in favor of chromic acid oxidation of D-galactose to D-galactonic acid in aqueous media at room temperature

    NASA Astrophysics Data System (ADS)

    Saha, Rumpa; Ghosh, Aniruddha; Sar, Pintu; Saha, Indrajit; Ghosh, Sumanta K.; Mukherjee, Kakali; Saha, Bidyut

    2013-12-01

    Picolinic acid, 2,2‧-bipyridine and 1,10-phenanthroline promoted Cr(VI) oxidation of D-galactose to D-galactonic acid in three representative aqueous micellar media has been studied. The anionic surfactant (SDS) accelerated the rate of reaction while the cationic surfactant (CPC) and neutral surfactant (TX-100) retarded the reaction rate. Combination of bipy and SDS is the best choice for chromic acid oxidation of D-galactose to D-galactonic acid in aqueous media although 1,10-phenanthroline is best promoter in absence of micellar catalyst.

  2. Incidence and cost of non-fatal burns in Iran: a nationwide population-based study.

    PubMed

    Abouie, Abolfazl; Salamati, Payman; Hafezi-Nejad, Nima; Rahimi-Movaghar, Afarin; Saadat, Soheil; Amin-Esmaeili, Masoumeh; Sharifi, Vandad; Hajebi, Ahmad; Rahimi-Movaghar, Vafa

    2017-04-07

    To determine the incidence and cost of non-fatal burns in Iran; this cross-sectional household survey of a nationally representative sample of 15-64 years old was conducted. Through face-to-face interviews and telephone calls, the data on the demographics, history and cost of burns were collected. The annual incidence rate of burns was estimated 129.85 per 1000 population. Burns occurred higher in younger age, female gender and urban residency. The most common burn description was as follows: unpaid work (activity during burn), home (place of burn), heat and hot substances (mechanism of burn) and upper limb (site of burn). The average total cost of burn includes victims seeking medical care was US$124 per case. The main findings of this study suggest that burns are a major public health concern in Iran. To stop this important health issue, a national program for burn prevention and education must be developed.

  3. Reducing Uncertainties in the Production of the Gamma-emitting Nuclei 26Al, 44Ti, and 60Fe in Core-collapse Supernovae by Using Effective Helium Burning Rates

    NASA Astrophysics Data System (ADS)

    Austin, Sam M.; West, Christopher; Heger, Alexander

    2017-04-01

    We have used effective reaction rates (ERRs) for the helium burning reactions to predict the yield of the gamma-emitting nuclei 26Al, 44Ti, and 60Fe in core-collapse supernovae (SNe). The variations in the predicted yields for values of the reaction rates allowed by the ERR are much smaller than obtained previously, and smaller than other uncertainties. A “filter” for SN nucleosynthesis yields based on pre-SN structure was used to estimate the effect of failed SNe on the initial mass function averaged yields; this substantially reduced the yields of all these isotopes, but the predicted yield ratio 60Fe/26Al was little affected. The robustness of this ratio is promising for comparison with data, but it is larger than observed in nature; possible causes for this discrepancy are discussed.

  4. Description of Missouri children who suffer burn injuries

    PubMed Central

    Quayle, K; Wick, N; Gnauck, K; Schootman, M; Jaffe, D

    2000-01-01

    Objective—This study uses Missouri's inpatient and outpatient E code data system to describe the demographic characteristics of Missouri children who suffered burn injuries during 1994 and 1995. Methods—Retrospective review of Missouri E code data. Results—Altogether 8404 children aged 0–14 years were treated for burn injuries in Missouri hospitals during 1994 and 1995. The rate of burn injury in Missouri children was 339 per 100 000/year. African-American boys 0–4 years living in urban counties were at increased risk. In addition, African-American girls ages 0–4 years living in counties with a high poverty rate had raised burn injury rates. Burns from hot objects and scalds from hot liquids caused more than half of the burns. Conclusions—Hospital based E coding has proven an invaluable tool for the study of burns and will, no doubt, prove equally useful for other injuries. PMID:11144622

  5. Epidemiology of hospitalized female burns patients in a burn centre in Shiraz.

    PubMed

    Hosseini, R S; Askarian, M; Assadian, O

    2007-01-01

    During 2000 to 2001, all 170 female burn patients admitted to the Ghotbeddin Burn Centre in Shiraz were studied to determine the epidemiological characteristics and outcome of burn for these patients. The overall mortality rate was 64%. The highest frequency of burns (53.5%) occurred among 16-25-year-olds. The commonest cause of burn was flame (98.2%). The mean (SD) length of hospital stay was 13 (14.3) days. Mean (SD) of total body surface area (TBSA) burned among all patients was 56% (28.5%); among those who survived it was 29% (13.4%) and among those who died it was 72% (21.7%). The relation between TBSA and mortality was statistically significant.

  6. Spread of Burn and Non-burn Pathologies, Anaesthetic Support and some Management Data

    PubMed Central

    Belba, M.; Belba, G.

    2007-01-01

    Summary In this article we present the surgical activity of the Burns Service in the University Hospital Centre in Tirana. Not only burn patients but also patients with trauma and soft tissue losses are hospitalized in a burns centre, as well as patients needing plastic surgery coming from similar specialities. In 2006, 1127 patients were subjected to surgery in our service. The techniques of anaesthesia used are general anaesthesia (endotracheal tube, laryngeal mask airway, intravenous) and regional anaesthesia. An anaesthesiologist acting in the role of physician manager can add significant value to the overall operating room process by improving efficiency in resource utilization and simultaneously quality of care. We have found that giving priority to burns, including burns sequelae and other hospitalized burn patients, if possible in day surgery, can optimize the bed occupancy rate. PMID:21991085

  7. Digital imaging in remote diagnosis of burns.

    PubMed

    Roa, L; Gómez-Cía, T; Acha, B; Serrano, C

    1999-11-01

    Images are capable of giving an accurate representation of skin color and have been used extensively in teaching about and researching burn therapy. The advance from analogue to digital imaging allows the remote transmission of the clinical information contained in the digital image of a burn, using a suitable system. The large size of these image files reduces transmission speed and makes data compression desirable. Compression, by means of the JPEG algorithm, of up to 50 times the original size of 38 digital images of burns suffered by 22 consecutive patients did not lessen its great usefulness in determining the depth of burn injuries, according to a group of experts in burn care. The success rate was close to 90%, both for non-compressed images in original BMP format (mean size:1500 Kb) and for compressed images with a Q index of 50 (30 Kb files), when compared with the clinical diagnoses confirmed one week after the accident.

  8. In Situ Burning of Oil Spills.

    PubMed

    Evans, D D; Mulholland, G W; Baum, H R; Walton, W D; McGrattan, K B

    2001-01-01

    For more than a decade NIST conducted research to understand, measure and predict the important features of burning oil on water. Results of that research have been included in nationally recognized guidelines for approval of intentional burning. NIST measurements and predictions have played a major role in establishing in situ burning as a primary oil spill response method. Data are given for pool fire burning rates, smoke yield, smoke particulate size distribution, smoke aging, and polycyclic aromatic hydrocarbon content of the smoke for crude and fuel oil fires with effective diameters up to 17.2 m. New user-friendly software, ALOFT, was developed to quantify the large-scale features and trajectory of wind blown smoke plumes in the atmosphere and estimate the ground level smoke particulate concentrations. Predictions using the model were tested successfully against data from large-scale tests. ALOFT software is being used by oil spill response teams to help assess the potential impact of intentional burning.

  9. Epidemic of charcoal burning suicide in Japan.

    PubMed

    Yoshioka, Eiji; Hanley, Sharon J B; Kawanishi, Yasuyuki; Saijo, Yasuaki

    2014-01-01

    The charcoal burning suicide epidemics in both Hong Kong and Taiwan have been well documented. However, little is known about the situation in Japan. To examine the impact of charcoal burning suicide on the overall and other method-specific suicide rates between 1998 and 2007 in Japan. Using data obtained from the Vital Statistics of Japan, negative binomial regression analyses were performed to investigate the impact of the charcoal burning method. In males and females aged 15-24 and 25-44 years, the charcoal burning epidemic led to a substantial increase in overall suicides, without a decrease in other methods. In all other age groups, no such trend was observed. In young Japanese, the charcoal burning method may have appealed to individuals who might not have chosen other highly or relatively lethal methods, and consequently led to an increase in overall suicides.

  10. Characterization of burn injuries using terahertz time-domain spectroscopy

    NASA Astrophysics Data System (ADS)

    Arbab, M. Hassan; Dickey, Trevor C.; Winebrenner, Dale P.; Chen, Antao; Mourad, Pierre D.

    2011-03-01

    The accuracy rates of the clinical assessment techniques used in grading burn injuries remain significantly low for partial thickness burns. In this paper, we present experimental results from terahertz characterization of 2nd and 3rd degree burn wounds induced on a rat model. Reflection measurements were obtained from the surface of both burned and normal skin using pulsed terahertz spectroscopy. Signal processing techniques are described for interpretation of the acquired terahertz waveform and differentiation of burn wounds. Furthermore, the progression of burn injuries is shown by comparison between acute characterization and 72-hours survival studies. While the water content of healthy and desiccated skin has been considered as a source of terahertz signal contrast, it is demonstrated that other biological effects such as formation of post-burn interstitial edema as well as the density of the discrete scattering structures in the skin (such as hair follicles, sweat glands, etc.) play a significant role in the terahertz response of the burn wounds.

  11. Mental health outcomes of burn: A longitudinal population-based study of adults hospitalized for burns.

    PubMed

    Logsetty, Sarvesh; Shamlou, Amir; Gawaziuk, Justin P; March, Justin; Doupe, Malcolm; Chateau, Dan; Hoppensack, Mike; Khan, Sazzadul; Medved, Maria; Leslie, William D; Enns, Murray W; Stein, Murray B; Asmundson, Gordon J G; Sareen, Jitender

    2016-06-01

    This study investigates the increased risk of mental health outcomes and health care utilization associated with burn with two year of follow-up using a longitudinal population-based matched cohort design. Adult burn survivors (n=157) were identified from a provincial burn registry and matched 1:5 with non-burn control subjects from the general population (matching variables age and gender). The prevalence of mental health outcomes and the rates of health care utilization between the groups were compared for the 2years pre and post index date using anonymously linked population-based administrative health care data. Rates were adjusted for age, gender and sociodemographic characteristics. While the burn cohort had an increased prevalence of mental health problems after burn compared to the control cohort, the burn group also had an increased prevalence of pre-burn depression (16.6% vs 7.8%; p=0.0005) and substance use disorders (8.9% vs 3.2%; p=0.001) when compared to controls. Once the pre-existing prevalence of mental illness was taken into account there was no significant change in the prevalence of mental health problems when comparing the burn group to controls over time. Although burns may not increase rates of mental health issues and health care utilization, burn survivors are a vulnerable group who already demonstrate increased rates of psychopathology and need for care. The present study highlights the importance of assessment and treatment of mental health outcomes in this population. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

  12. Erosive Burning Study Utilizing Ultrasonic Measurement Techniques

    NASA Technical Reports Server (NTRS)

    Furfaro, James A.

    2003-01-01

    A 6-segment subscale motor was developed to generate a range of internal environments from which multiple propellants could be characterized for erosive burning. The motor test bed was designed to provide a high Mach number, high mass flux environment. Propellant regression rates were monitored for each segment utilizing ultrasonic measurement techniques. These data were obtained for three propellants RSRM, ETM- 03, and Castor@ IVA, which span two propellant types, PBAN (polybutadiene acrylonitrile) and HTPB (hydroxyl terminated polybutadiene). The characterization of these propellants indicates a remarkably similar erosive burning response to the induced flow environment. Propellant burnrates for each type had a conventional response with respect to pressure up to a bulk flow velocity threshold. Each propellant, however, had a unique threshold at which it would experience an increase in observed propellant burn rate. Above the observed threshold each propellant again demonstrated a similar enhanced burn rate response corresponding to the local flow environment.

  13. Burning mouth syndrome and secondary oral burning.

    PubMed

    Minor, Jacob S; Epstein, Joel B

    2011-02-01

    Burning mouth syndrome is a complex disorder of unclear etiology that is most prevalent in perimenopausal women. It is often accompanied by dysguesia and subjective xerostomia. Recent evidence implicates both central and peripheral neuropathies, possibly representing a phantom pain syndrome in some patients. Ensuring that the patient's oral burning is not secondary to some other local or systemic factor is central to appropriate management. Current standard therapies include clonazepam, paroxetine, and cognitive behavioral therapy, and several promising new alternatives are described.

  14. Catalysts for Dehydrogenation of ammonia boranes

    SciTech Connect

    Heinekey, Dennis M.

    2009-10-31

    Several effective homogeneous catalysts for the dehydrogenation of amine boranes have been developed. The best catalyst uses an iridium complex, and is capable of dehydrogenating H3NBH3 (AB) and CH3NH2BH3 (MeAB) at comparable rates. Thermodynamic measurements using this catalyst demonstrate that the dehydrogenation of AB and MeAB is substantially exothermic, which has important implications for regeneration.

  15. Bizarre paediatric facial burns.

    PubMed

    Ho, W S; Ying, S Y; Wong, T W

    2000-08-01

    Child abuse and neglect account for a significant number of paediatric burn injuries. It is of great importance because of the high mortality, high frequency of repeated abuse, as well as the physical, psychological and social sequelae that it causes. Burn abuse is often under-recognized and under-reported because it is difficult to define non-accidental injury. On the other hand, false accusation of burn abuse is extremely damaging to the family. Bizarre and unusual burn injuries can be caused by accident and should not automatically be assumed to be deliberate injury. Three boys of age 1-7 years with bizarre facial burns were admitted to the Burns Unit at the Prince of Wales Hospital between February 1995 and July 1999. One was burned by his baby-sitter with hot water steam and the other two were burned by their mothers with hot boiled eggs. The unusual causes of their burns raised the suspicion of child abuse and formal investigations were carried out by the Social Services Department. Detail assessment including a developmental history of the child and the psychosocial assessment of the family revealed that these three boys were burned because of poor medical advice and innocent cultural belief.

  16. Burns in pregnancy.

    PubMed

    Maghsoudi, Hemmat; Samnia, Roya; Garadaghi, Abasad; Kianvar, Hadi

    2006-03-01

    A 9-year prospective study of burns in pregnant women hospitalized at the Sina hospital burn center was conducted to determine the etiology and outcome of pregnant patients. Fifty-one patients (27.45% self-inflicted, 72.55% unintentional) were identified and stratified by age, burn size, presence or absence of inhalation injury, trimester of pregnancy, maternal and fetal mortality, and cause of burn. The mean patient age was 24.2 years. There were 20 maternal deaths and 23 fetal deaths. The majority of which (maternal: 13 and fetal: 13) were among self-inflicted burned pregnant women. The mean burn size was 37.7%, and was significantly larger for nonsurvivors of mother than survivors (68.8% versus 17.6%; p<0.001). In the 51 pregnant women, as the total burned body surface area exceeds 40%, both maternal and fetal mortality reaches 100%. Inhalation injuries were strongly associated with large burns, and were presents in all suicide patients. Kerosene ignition (68.6% of all patients, 100% of self-inflicted patients) was the most common type of burn. Large burn size was the strongest predictor of mortality of mother and fetus followed by the presence of inhalation injury.

  17. [The pain from burns].

    PubMed

    Latarjet, J

    2002-03-01

    The painful events associated with the treatment of a severe burn can, because of their long-lasting and repetitive characteristics, be one of the most excruciating experiences in clinical practice. Moreover, burn pain has been shown to be detrimental to burn patients. Although nociception and peripheral hyperalgesia are considered the major causes of burn pain, the study of more hypothetical mechanisms like central hyperalgesia and neuropathic pain may lead to a better understanding of burn pain symptoms and to new therapeutic approaches. Continuous pain and intermittent pain due to therapeutic procedures are two distinct components of burn pain. They have to be evaluated and managed separately. Although continuous pain is by far less severe than intermittent pain, the treatment is, in both cases, essentially pharmacological relying basically on opioids. Because of wide intra- and inter-individual variations, protocols will have to leave large possibilities of adaptation for each case, systematic pain evaluation being mandatory to achieve the best risk/benefit ratio. Surprisingly, the dose of medication decreases only slowly with time, a burn often remaining painful for long periods after healing. Non pharmacological treatments are often useful and sometimes indispensable adjuncts; but their rationale and their feasibility depends entirely on previous optimal pharmacological control of burn pain. Several recent studies show that burn pain management is inadequate in most burn centres.

  18. Cracking catalyst

    SciTech Connect

    Otterstedt, J. E. A.; Jaras, S. G.; Pudas, R.; Upson, L. L.

    1985-05-07

    A cracking catalyst having good resistance to metal poisoning has at least two particle fractions of different particle sizes, the cracking catalyzing zeolite material being concentrated to the coarser particle size fractions, and the finer particle size fractions being formed from material having relatively lower or no or insignificant cracking catalyzing activity. The particles of the finer particle size fractions have a matrix of kaolin and amorphous alumina--silica and may contain for example, an SO /SUB x/ eliminating additive such as Al/sub 2/O/sub 3/, CaO and/or MgO. The coarser particle size fractions having cracking catalyzing effect have a mean particle size of from 80 to 125 ..mu..m and the finer particle size fractions a mean particle size of from 30 to 75 ..mu..m. The coarser particle size fractions have a zeolite content of at least 20 weight % and may have a zeolite content of up to 100 weight %, the remainder consisting essentially of material which has relatively lower or no or insignificant cracking-catalyzing activity and which consists of kaolin and amorphous alumina-silica. The catalyst mass as a whole may have a zeolite content of up to 50 weight %.

  19. Ethanol oxidation on metal oxide-supported platinum catalysts

    SciTech Connect

    L. M. Petkovic 090468; Sergey N. Rashkeev; D. M. Ginosar

    2009-09-01

    Ethanol is a renewable fuel that can be used as an additive to gasoline (or its substitute) with the advantage of octane enhancement and reduced carbon monoxide exhaust emissions. However, on Ethanol is a renewable fuel that can be used as an additive to gasoline (or its substitute) with the advantage of octane enhancement and reduced carbon monoxide exhaust emissions. However, on the standard three-way catalysts, the conversion of unburned ethanol is low because both ethanol and some of its partially oxidized derivatives are highly resistant to oxidation. A combination of first-principles density-functional theory (DFT) based calculations and in-situ diffuse reflectance infrared spectroscopy (DRIFTS) analysis was applied to uncover some of the fundamental phenomena associated with ethanol oxidation on Pt containing catalysts. In particular, the objective was to analyze the role of the oxide (i.e., ?-Al2O3 or SiO2) substrate on the ethanol oxidation activity. The results showed that Pt nanoparticles trap and accumulate oxygen at their surface and perimeter sites and play the role of “stoves” that burn ethanol molecules and their partially oxidized derivatives to the “final” products. The ?-Al2O3 surfaces provided higher mobility of the fragments of ethanol molecules than the SiO2 surface and hence increased the supply rate of these objects to the Pt particles. This will in turn produce a higher conversion rate of unburned ethanol.and some of its partially oxidized derivatives are highly resistant to oxidation. A combination of first-principles density-functional theory (DFT) based calculations and in-situ diffuse reflectance infrared spectroscopy (DRIFTS) analysis was applied to uncover some of the fundamental phenomena associated with ethanol oxidation on Pt containing catalysts. In particular, the objective was to analyze the role of the oxide (i.e., ?-Al2O3 or SiO2) substrate on the ethanol oxidation activity. The results showed that Pt nanoparticles

  20. Predictors of Muscle Protein Synthesis after Severe Pediatric Burns

    PubMed Central

    Diaz, Eva C.; Herndon, David N.; Lee, Jinhyung; Porter, Craig; Cotter, Matthew; Suman, Oscar E.; Sidossis, Labros S.; Børsheim, Elisabet

    2015-01-01

    Background Following a major burn, skeletal muscle protein synthesis rate increases, but is often insufficient to compensate for massively elevated muscle protein breakdown rates. Given the long-term nature of the pathophysiologic response to burn injury, we hypothesized that muscle protein synthesis rate would be chronically elevated in severely burned children. The objectives of this study were to characterize muscle protein synthesis rate of burned children over a period of 24 months post-injury, and identify predictors that influence this response. Study design 87 children with ≥40% total body surface area (TBSA) burn were included. Patients participated in stable isotope infusion studies at 1, 2 and ~ 4 weeks post-burn, and at 6, 12 and 24 months post-injury to determine skeletal muscle fractional synthesis rate. Generalized estimating equations with log link normal distribution were applied to account for clustering of patients and control for patient characteristics. Results Patients (8±6 years) had large (62, 51–72% TBSA) and deep (47±21% TBSA third degree) burns. Muscle fractional synthesis rate was elevated throughout the first 12 months post-burn compared to established values from healthy young adults. Muscle fractional synthesis rate was lower in boys, children >3 years old, and when burns were >80% TBSA. Conclusions Muscle protein synthesis is elevated for at least one year after injury, suggesting that greater muscle protein turnover is a component of the long-term pathophysiological response to burn trauma. Muscle protein synthesis is highly affected by gender, age and burn size in severely burned children. These findings may explain the divergence in net protein balance and lean body mass in different populations of burn victims. PMID:25807408

  1. Do burns increase the severity of terror injuries?

    PubMed

    Peleg, Kobi; Liran, Alon; Tessone, Ariel; Givon, Adi; Orenstein, Arie; Haik, Josef

    2008-01-01

    The use of explosives and suicide bombings has become more frequent since October 2000. This change in the nature of terror attacks has marked a new era in the Israeli-Palestinian conflict. We previously reported that the incidence of thermal injuries has since risen. However, the rise in the incidence of burns among victims of terror was proportionate to the rise in the incidence of burns among all trauma victims. This paper presents data from the Israeli National Trauma Registry during the years 1997--2003, to compare the severity of injuries and outcome (mortality rates) in terror victims with and without burn injuries. We also compare the severity of injuries and outcome (mortality rates) for patients with terror-attack related burns to non terror-attack related burns during the same period. Data was obtained from the Israeli National Trauma Registry for all patients admitted to 8 to 10 hospitals in Israel between 1997 and 2003. We analyzed and compared demographic and clinical characteristics of 219 terror-related burn patients (terror/burn), 2228 terror patients with no associated burns (Terror/no-burn) and 6546 non terror related burn patients (burn/no-terror). Severity of injuries was measured using the injury severity score, and burn severity by total body surface percentage indices. Admission rates to Intensive Care Units (ICU) and total length of hospitalization were also used to measure severity of injuries. In-hospital mortality rates were used to indicate outcome. Of burn/terror patients, 87.2% suffered other accompanying injuries, compared with 10.4% of burn/no-terror patients. Of burn/terror patients, 49.8% were admitted to ICU compared with only 11.9% of burn/no-terror patients and 23.8% of no-burn/terror patients. Mean length of hospital stay was 18.5 days for the terror/burn group compared with 11.1 days for the burn/no-terror group and 9.5 days for the terror/no-burn group. Burn/terror patients had a significantly higher injury severity score

  2. Environmentally benign production of biodiesel using heterogeneous catalysts.

    PubMed

    Hara, Michikazu

    2009-01-01

    Fuelling the future: The production of esters of higher fatty acids from plant materials is of great interest for the manufacture of biodiesel. Heterogeneous catalysts can provide new routes for the environmentally benign production of biodiesel. Particulate heterogeneous catalysts can be readily separated from products following reaction allowing the catalyst to be reused, generating less waste, and consuming less energy. Diesel engines are simple and powerful, and exhibit many advantages in energy efficiency and cost. Therefore, the production of higher fatty acid esters from plant materials has become of interest in recent years for the manufacture of biodiesel, a clean-burning alternative fuel. The industrial production of biodiesel mostly proceeds in the presence of "soluble" catalysts such as alkali hydroxides and liquid acids. A considerable amount of energy is required for the purification of products and catalyst separation, and furthermore these catalysts are not reusable. This process results in substantial energy wastage and the production of large amounts of chemical waste. Particulate heterogeneous catalysts can be readily separated from products following reaction, allowing the catalyst to be reused and consuming less energy. This Minireview describes the environmentally benign production of biodiesel using heterogeneous catalysts such as solid bases, acid catalysts, and immobilized enzymes.

  3. Burns associated with fondues.

    PubMed Central

    Laliberté, D; Beaucage, C; Watts, N

    1992-01-01

    OBJECTIVE: To describe the causes of burns associated with fondues. DESIGN: Descriptive case series. PATIENTS: All 17 patients admitted to a burn centre between Apr. 1, 1985, and Mar. 31, 1990, whose burns were associated with fondue. Eleven agreed to complete a telephone interview. RESULTS: The age of the 17 patients varied from 2 to 56 (mean 27) years. Two causes were identified: spilling of the contents of the fondue pot and explosion of the fondue fuel when added to the burner during a meal. The telephone interview revealed that eight people other than the respondents were burned during the same accidents. CONCLUSION: Although we identified only badly burned patients the problem may be more extensive. The knowledge of specific causes of burns from handling fondue equipment indicates that preventive action should be undertaken. More epidemiologic information is needed to obtain a precise estimate of the magnitude of this public health problem. PMID:1393897

  4. Burns associated with fondues.

    PubMed

    Laliberté, D; Beaucage, C; Watts, N

    1992-10-01

    To describe the causes of burns associated with fondues. Descriptive case series. All 17 patients admitted to a burn centre between Apr. 1, 1985, and Mar. 31, 1990, whose burns were associated with fondue. Eleven agreed to complete a telephone interview. The age of the 17 patients varied from 2 to 56 (mean 27) years. Two causes were identified: spilling of the contents of the fondue pot and explosion of the fondue fuel when added to the burner during a meal. The telephone interview revealed that eight people other than the respondents were burned during the same accidents. Although we identified only badly burned patients the problem may be more extensive. The knowledge of specific causes of burns from handling fondue equipment indicates that preventive action should be undertaken. More epidemiologic information is needed to obtain a precise estimate of the magnitude of this public health problem.

  5. [Treatment of mass burns].

    PubMed

    Zhou, Y

    1999-07-01

    Present paper aims at summing up the experience from 42 cases over a four year period(1993-1997) in ten events of mass burn casualties. 42 cases were analyzed retrospectively, in whom 15 cases sustained III degree burn over 50% TBSA. Among them 7 cases had III degree burn over 70% and 3 cases with III degree burn over 90%. One case (70% TBSA) died of acute respiratory distress syndrome on third postburn day. Another (III degree 70%) died of acute renal failure on seventh postburn day. The remaining 40 cases were successfully cured. Experiences gained in burn care in these ten mass casualties included: sending forward the medical expertise to the site of disaster; airlifting to accelerate transportation, adequate resuscitation in shock stage; early massive excision of eschar and skin grafting; control of burn infection; prevention of Curling ulcer hemorrhage, emphasis on supportive therapy; and the establishment of a skin bank.

  6. Pediatric cutaneous bleach burns.

    PubMed

    Lang, Cathleen; Cox, Matthew

    2013-07-01

    Bleach is a common household product which can cause caustic injuries. Its effects on mucosal tissues and the eye have been well-described in the literature. However, there is little information published regarding the appearance and effect of bleach on a child's skin. We report three children who sustained chemical burns after contact with bleach. All three children sustained accidental bleach burns while at home, and each child had a distinct brown discoloration to the skin from the injury. All three children had treatment and follow-up for their burns. Two of the children sustained more severe burns, which were extensive and required more time to heal. There was also long-term scarring associated with the severe burns. Like most burns, pain control is required until the injury heals. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Wound management and outcome of 595 electrical burns in a major burn center.

    PubMed

    Li, Haisheng; Tan, Jianglin; Zhou, Junyi; Yuan, Zhiqiang; Zhang, Jiaping; Peng, Yizhi; Wu, Jun; Luo, Gaoxing

    2017-06-15

    Electrical burns are important causes of trauma worldwide. This study aims to analyze the clinical characteristics, wound management, and outcome of electric burns. This retrospective study was performed at the Institute of Burn Research of the Third Military Medical University during 2013-2015. Data including the demographics, injury patterns, wound treatment, and outcomes were collected and analyzed. A total of 595 electrical burn patients (93.8% males) were included. The average age was 37.3 ± 14.6 y, and most patients (73.5%) were aged 19∼50 years. Most patients (67.2%) were injured in work-related circumstances. The mean total body surface area was 8.8 ± 11.8% and most wounds (63.5%) were full-thickness burns. Operation times of high-voltage burns and current burns were higher than those of low-voltage burns and arc burns, respectively. Of the 375 operated patients, 83.2% (n = 312) underwent skin autografting and 49.3% (n = 185) required skin flap coverage. Common types of skin flaps were adjacent (50.3%), random (42.2%), and pedicle (35.7%). Amputation was performed in 107 cases (18.0%) and concentrated on the hands (43.9%) and upper limbs (39.3%). The mean length of stay was 42.9 ± 46.3 d and only one death occurred (0.2%). Current burns and higher numbers of operations were major risk factors for amputation and length of stay, respectively. Electrical burns mainly affected adult males with occupational exposures in China. Skin autografts and various skin flaps were commonly used for electric burn wound management. More standardized and effective strategies of treatment and prevention are still needed to decrease amputation rates. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. One Burn, One Standard

    DTIC Science & Technology

    2014-09-01

    for supporting burn treatment has induced a rethinking of current medical documentation processes of burns, especially with respect to the Lund...Browder burn diagram. In the past, the lack of comparability, scientific evalu- ation possibilities, and as a consequence, missing medical evidence in...to interested parties after registration. To that end, a protected (everyone is able to read the content, one has to register to edit) wiki (www

  9. Nitrogen-doped aligned carbon nanotube/graphene sandwiches: facile catalytic growth on bifunctional natural catalysts and their applications as scaffolds for high-rate lithium-sulfur batteries.

    PubMed

    Tang, Cheng; Zhang, Qiang; Zhao, Meng-Qiang; Huang, Jia-Qi; Cheng, Xin-Bing; Tian, Gui-Li; Peng, Hong-Jie; Wei, Fei

    2014-09-17

    Nitrogen-doped aligned CNT/graphene sandwiches are rationally designed and in-situ fabricated by a facile catalytic growth on bifunctional natural catalysts that exhibit high-rate performances as scaffolds for lithium-sulfur batteries, with a high initial capacity of 1152 mA h g(-1) at 1.0 C. A remarkable capacity of 770 mA h g(-1) can be achieved at 5.0 C. Such a design strategy for materials opens up new perspectives to novel advanced functional composites, especially interface-modified hierarchical nanocarbons for broad applications.

  10. Circulatory disease mortality rates in the elderly and exposure to PM(2.5) generated by biomass burning in the Brazilian Amazon in 2005.

    PubMed

    Nunes, Karine Vila Real; Ignotti, Eliane; Hacon, Sandra de Souza

    2013-03-01

    The aim of this study was to analyze the association between the exposure to fine particulate matter and circulatory disease mortality rates in the elderly living in the Brazilian Amazon. An ecological study of circulatory disease, acute myocardial infarction and cerebrovascular disease mortality rates in micro areas of the Brazilian Amazon was carried out. The environmental exposure indicator used was percentage hours of PM(2.5) concentrations > 25µg/m(3) divided by the total number of estimated hours of PM(2.5) in 2005. The association between exposure and circulatory disease mortality rates was strongest in the oldest age group. No significant statistical association was found between cerebrovascular disease mortality rates and exposure. Circulatory disease mortality rates in the elderly living in the Amazon have been influenced by atmospheric pollution from emissions caused by forest fires.

  11. Burn Wound Infections

    PubMed Central

    Church, Deirdre; Elsayed, Sameer; Reid, Owen; Winston, Brent; Lindsay, Robert

    2006-01-01

    Burns are one of the most common and devastating forms of trauma. Patients with serious thermal injury require immediate specialized care in order to minimize morbidity and mortality. Significant thermal injuries induce a state of immunosuppression that predisposes burn patients to infectious complications. A current summary of the classifications of burn wound infections, including their diagnosis, treatment, and prevention, is given. Early excision of the eschar has substantially decreased the incidence of invasive burn wound infection and secondary sepsis, but most deaths in severely burn-injured patients are still due to burn wound sepsis or complications due to inhalation injury. Burn patients are also at risk for developing sepsis secondary to pneumonia, catheter-related infections, and suppurative thrombophlebitis. The introduction of silver-impregnated devices (e.g., central lines and Foley urinary catheters) may reduce the incidence of nosocomial infections due to prolonged placement of these devices. Improved outcomes for severely burned patients have been attributed to medical advances in fluid resuscitation, nutritional support, pulmonary and burn wound care, and infection control practices. PMID:16614255

  12. Burn wound infections.

    PubMed

    Church, Deirdre; Elsayed, Sameer; Reid, Owen; Winston, Brent; Lindsay, Robert

    2006-04-01

    Burns are one of the most common and devastating forms of trauma. Patients with serious thermal injury require immediate specialized care in order to minimize morbidity and mortality. Significant thermal injuries induce a state of immunosuppression that predisposes burn patients to infectious complications. A current summary of the classifications of burn wound infections, including their diagnosis, treatment, and prevention, is given. Early excision of the eschar has substantially decreased the incidence of invasive burn wound infection and secondary sepsis, but most deaths in severely burn-injured patients are still due to burn wound sepsis or complications due to inhalation injury. Burn patients are also at risk for developing sepsis secondary to pneumonia, catheter-related infections, and suppurative thrombophlebitis. The introduction of silver-impregnated devices (e.g., central lines and Foley urinary catheters) may reduce the incidence of nosocomial infections due to prolonged placement of these devices. Improved outcomes for severely burned patients have been attributed to medical advances in fluid resuscitation, nutritional support, pulmonary and burn wound care, and infection control practices.

  13. Choosing Wood Burning Appliances

    EPA Pesticide Factsheets

    Information to assist consumers in choosing a wood burning appliance, including types of appliances, the differences between certified and non-certified appliances, and alternative wood heating options.

  14. Characteristics of burn patients injured in methamphetamine laboratory explosions.

    PubMed

    Spann, Matthew D; McGwin, Gerald; Kerby, Jeffrey D; George, Richard L; Dunn, Shane; Rue, Loring W; Cross, James M

    2006-01-01

    The use of methamphetamine (MA) as a recreational drug has increased exponentially in recent years, resulting in an emergence of clandestine laboratories. Consequently, the frequency with which burn centers across the country are admitting patients injured as a consequence of the volatile manufacturing process of MA is increasing. This study focused on comparing outcomes between burn patients injured secondary to MA laboratory explosions and patients sustaining burns from other mechanisms. All patients identified to have suffered burns secondary to MA laboratory explosions between 1998 and 2004 were included in this study. These patients were compared with those who did not experience such burns during this same time period. In total, 19 patients were identified as having been burned in MA laboratory explosions. These patients had a larger component of third-degree burns (24.8% vs 13.5%; P < .05) as well as TBSA burned (28.4% vs 20.7%; P < .05). In addition, patients using MA had an increased incidence of inhalation injury (31.2% vs 6.1%; P < .05). They also exhibited a significantly increased frequency of complications, such as nosocomial pneumonia, respiratory failure, and sepsis. Overall, the rate of mortality was significantly increased in patients using MA (26.3% vs 8.5%; P < .05); however, no significant difference was observed after adjustment for age, burn size, and inhalation injury. MA burn patients have larger burn size, incidence of inhalation injury, and increased morbidity when compared with non-MA burn patients.

  15. Root Disease, Longleaf Pine Mortality, and Prescribed Burning

    SciTech Connect

    Otrosina, W.J; C.H. Walkinshaw; S.J. Zarnoch; S-J. Sung; B.T. Sullivan

    2001-01-01

    Study to determine factors involved in decline of longleaf pine associated with prescribed burning. Trees having symptoms were recorded by crown rating system based upon symptom severity-corresponded to tree physiological status-increased in hot burn plots. Root pathogenic fungi widespread throughout the study site. Histological studies show high fine root mortality rate in the hot burn treatment. Decline syndrome is complexed by root pathogens, soil factors, root damage and dysfunction.

  16. Pharmacological Sparing of Protein in Burn Injury

    DTIC Science & Technology

    1988-05-10

    protein breakdown rates and factors other than insulin resistance are responsible for stimulating the net protein catabolism of severe burn injury and...suggest that the " insulin resistance " of sepsis may be different from that of severe trauma uncompli- cated by infection, we further tested the effect of...suggesting that factors other than insulin resistance were responsible for mediating the deranged protein metabolism of burns and sepsis. From studies by

  17. Burns and military clothing.

    PubMed

    McLean, A D

    2001-02-01

    Burn injury is a ubiquitous threat in the military environment. The risks during combat are well recognised, but the handling of fuel, oil, munitions and other hot or flammable materials during peacetime deployment and training also imposes an inherent risk of accidental burn injury. Over the last hundred years, the burn threat in combat has ranged from nuclear weapons to small shoulder-launched missiles. Materials such as napalm and white phosphorus plainly present a risk of burn, but the threat extends to encompass personnel in vehicles attacked by anti-armour weapons, large missiles, fuel-air explosives and detonations/conflagrations on weapons platforms such as ships. Large numbers of burn casualties were caused at Pearl Harbor, in Hiroshima and Nagasaki, Vietnam, during the Arab/Israeli Wars and in the Falkland Islands conflict. The threat from burns is unlikely to diminish, indeed new developments in weapons seek to exploit the vulnerability of the serviceman and servicewoman to burns. Clothing can be a barrier to some types of burn--both inherently in the properties of the material, but also by trapping air between clothing layers. Conversely, ignition of the clothing may exacerbate a burn. There is hearsay that burnt clothing products within a wound may complicate the clinical management, or that materials that melt (thermoplastic materials) should not be worn if there is a burn threat. This paper explores the incidence of burn injury, the mechanisms of heat transfer to bare skin and skin covered by materials, and the published evidence for the complication of wound management by materials. Even light-weight combat clothing can offer significant protection to skin from short duration flash burns; the most vulnerable areas are the parts of the body not covered--face and hands. Multilayered combat clothing can offer significant protection for short periods from engulfment by flames; lightweight tropical wear with few layers offers little protection. Under

  18. [Burn rehabilitation and community reintegration-new challenge to burn surgery in China].

    PubMed

    Xie, Wei-Guo

    2010-12-01

    Burn patients often have severe disfigurement, dysfunction, and psychological disorder after discharge, which may last for a long time, even for a whole life. These problems may prevent patients from returning to normal life and re-entering society. Because of demographic and socioeconomic reasons, the number of burn patients in China is huge. The rising cure rate further increases the number of patients that need rehabilitation treatment. However, the level of burn rehabilitation in China is relatively low as compared with that in the developed countries. Along with the social and economical development, it is no longer satisfied to just save the life of patient. Improving the quality of wound healing, avoiding or decreasing disfigurement, dysfunction, and psychological disorder, and finally helping patients re-enter society is the ultimate goal of burn treatment. Modern concept of rehabilitation is to restore health or normal life for patients by medical, psychosocial, educational and occupational methods. Although increasing attention has been paid to burn rehabilitation in China recently, so far it is mainly focused on the fields of improving patients' appearance and body function, whereas the importance of psychosocial, educational, occupational, and social rehabilitation has still not been realized. Some fields of burn rehabilitation have not been well established and many are not carried out by professionals. The model of multidisciplinary team in burn centers of developed countries including surgeons and nurses, as well as allied professionals such as psychologists, physical and occupational therapists, dietitians, anesthesiologists and social workers has seldom been introduced into China. In most burn centers in China, psychological support is mainly given by nurses in their spare time of nursing. Burn treatment used to be divided into the early stage of life saving and wound repair, and the late stage of rehabilitation. It has not been realized until

  19. Electrochemical catalyst recovery method

    DOEpatents

    Silva, Laura J.; Bray, Lane A.

    1995-01-01

    A method of recovering catalyst material from latent catalyst material solids includes: a) combining latent catalyst material solids with a liquid acid anolyte solution and a redox material which is soluble in the acid anolyte solution to form a mixture; b) electrochemically oxidizing the redox material within the mixture into a dissolved oxidant, the oxidant having a potential for oxidation which is effectively higher than that of the latent catalyst material; c) reacting the oxidant with the latent catalyst material to oxidize the latent catalyst material into at least one oxidized catalyst species which is soluble within the mixture and to reduce the oxidant back into dissolved redox material; and d) recovering catalyst material from the oxidized catalyst species of the mixture. The invention is expected to be particularly useful in recovering spent catalyst material from petroleum hydroprocessing reaction waste products having adhered sulfides, carbon, hydrocarbons, and undesired metals, and as well as in other industrial applications.

  20. Electrochemical catalyst recovery method

    DOEpatents

    Silva, L.J.; Bray, L.A.

    1995-05-30

    A method of recovering catalyst material from latent catalyst material solids includes: (a) combining latent catalyst material solids with a liquid acid anolyte solution and a redox material which is soluble in the acid anolyte solution to form a mixture; (b) electrochemically oxidizing the redox material within the mixture into a dissolved oxidant, the oxidant having a potential for oxidation which is effectively higher than that of the latent catalyst material; (c) reacting the oxidant with the latent catalyst material to oxidize the latent catalyst material into at least one oxidized catalyst species which is soluble within the mixture and to reduce the oxidant back into dissolved redox material; and (d) recovering catalyst material from the oxidized catalyst species of the mixture. The invention is expected to be particularly useful in recovering spent catalyst material from petroleum hydroprocessing reaction waste products having adhered sulfides, carbon, hydrocarbons, and undesired metals, and as well as in other industrial applications. 3 figs.

  1. Epidemiology and outcome of burns: early experience at the country's first national burns centre.

    PubMed

    Iqbal, Tariq; Saaiq, Muhammad; Ali, Zahid

    2013-03-01

    This study aims to document the epidemiologic pattern and outcome of burn injuries in the country's first national burn centre. This case series study was conducted over a 2-year period at Burns Care Centre (BCC), Pakistan Institute of Medical Sciences (PIMS), Islamabad. The study included all burn injury patients who primarily presented to and were managed at the centre. Those patients who presented more than 24 h after injury or those who were initially managed at some other hospital were excluded from the study. Initial assessment and diagnosis was made by thorough history, physical examination and necessary investigations. Patients with major burns, high voltage electric burns and those needing any surgical interventions were admitted for indoor management. Patients with minor burns were discharged home after necessary emergency management, home medication and follow-up advice. The sociodemographic profile of the patients, site of sustaining burn injury, type and extent (total body surface area (TBSA), skin thickness involved and associated inhalational injury) of burn and outcome in terms of survival or mortality, etc., were all recorded on a proforma. The data were subjected to statistical analysis. Out of a total of 13,295 patients, there were 7503 (56.43%) males and 5792 (43.56%) females. The mean age for adults was 33.63±10.76 years and for children it was 6.71±3.47 years. The household environment constituted the commonest site of burns (68%). Among all age groups and both genders, scalds were the commonest burns (42.48%), followed by flame burns (39%) and electrical burns (9.96%). The affected mean TBSA was 10.64±11.45% overall, while for the hospitalised subset of patients the mean TBSA was 38.04±15.18%. Most of the burns were partial thickness (67%). Inhalation injury was found among 149 (1.12%) patients. Most of the burns were non-intentional and only 96 (0.72%) were intentional. A total of 1405 patients (10.58%) were admitted while the remainder

  2. Instrumented tube burns: theoretical and experimental observations

    SciTech Connect

    Yarrington, Cole Davis; Obrey, Stephen J; Foley, Timothy J; Son, Steven F

    2009-01-01

    The advent of widely available nanoscale energetic composites has resulted in a flurry of novel applications. One of these applications is the use of nanomaterials in energetic compositions. In compositions that exhibit high sensitivity to stimulus, these materials are often termed metastable intermolecular composites (MIC). More generally, these compositions are simply called nanoenergetics. Researchers have used many different experimental techniques to analyze the various properties of nanoenergetic systems. Among these various techniques, the confined tube burn is a simple experiment that is capable of obtaining much data related to the combustion of these materials. The purpose of this report is to review the current state of the confined tube burn experiment, including the drawbacks of the technique and possible remedies. As this report is intended to focus on the specific experimental technique, data from many different energetic materials, and experimental configurations will be presented. The qualitative and quantitative data that can be gathered using confined tube burn experiments include burning rates, total impulse, pressure rise rate, and burning rate differences between different detector types. All of these measurements lend insight into the combustion properties and mechanisms of specific nanoenergetics. Finally, certain data indicates a more complicated flow scenario which may need to be considered when developing burn tube models.

  3. Long-Life Catalyst

    NASA Technical Reports Server (NTRS)

    1999-01-01

    STC Catalysts, Inc. (SCi) manufactures a noble metal reducible oxide catalyst consisting primarily of platinum and tin dioxide deposited on a ceramic substrate. It is an ambient temperature oxidation catalyst that was developed primarily for Carbon Dioxide Lasers.The catalyst was developed by the NASA Langley Research Center for the Laser Atmospheric Wind Sounder Program (LAWS) which was intended to measure wind velocity on a global basis. There are a number of NASA owned patents covering various aspects of the catalyst.

  4. Biomass burning a driver for global change

    SciTech Connect

    Levine, J.S.; Cofer, W.R. III; Cahoon, D.R. Jr.; Winstead, E.L.

    1995-03-01

    Recent research has identified another biospheric process that has instantaneous and longer term effects on the production of atmospheric gases: biomass burning. Biomass burning includes the burning of the world`s vegetation-forests, savannas. and agricultural lands, to clear the land and change its use. Only in the past decade have researchers realized the important contributions of biomass burning to the global budgets of many radiatively and chemically active gases - carbon dioxide, methane, nitric oxide, tropospheric ozone, methyl chloride - and elemental carbon particulates. International field experiments and satellite data are yielding a clearer understanding of this important global source of atmospheric gases and particulates. It is seen that in addition to being a significant instantaneous global source of atmospheric gases and particulates, burning enhances the biogenic emissions of nitric oxide and nitrous oxide from the world`s soils. Biomass burning affects the reflectivity and emissivity of the Earth`s surface as well as the hydrological cycle by changing rates of land evaporation and water runoff. For these reasons, it appears that biomass burning is a significant driver of global change. 20 refs., 4 figs., 2 tabs.

  5. Zinc burns: a rare burn injury.

    PubMed

    de Juan, A; Ramon, P; Santoyo, F; Alonso, S

    2000-08-01

    A patient was presented with significant burns resulting from a workplace accident in a zinc production unit. This occurred as a result of the spontaneous combustion of zinc bleed under high pressure. The patient sustained burns to the face, body, and hands and suffered significant injury to the left cornea. Computed imaging revealed solid particles in the ethmoid sinus and also in the right nasal fossa, dissecting the right lacrimal duct. Photographic documentation is presented. This injury was potentially preventable and resulted from poor observance of safety procedures.

  6. Effectiveness of prophylactic antibiotics in the outpatient treatment of burns.

    PubMed

    Boss, W K; Brand, D A; Acampora, D; Barese, S; Frazier, W H

    1985-03-01

    We compared wound infection rates in 133 outpatient burns treated with prophylactic antibiotics in our emergency room and 161 similar, untreated burns. Infection rates in the treated and untreated groups were 3.8% (5/133) and 3.1% (5/161), respectively. Since this was an observational cohort study, it was necessary to demonstrate the comparability of treated and untreated groups with respect to risk factors for infection, including patient age, size, location, and etiology of the burn injury, time since injury, and presence of co-morbidity. The groups were found to be comparable for all risk factors except size of burn: larger burns were over-represented in the treated group (p less than 0.05). Even after controlling for size, antibiotic use did not lower the infection rate. These results argue strongly against routine use of systemic antibiotics in the treatment of outpatient burns.

  7. Pain in burn patients.

    PubMed

    Latarjet, J; Choinère, M

    1995-08-01

    While severe pain is a constant component of the burn injury, inadequate pain management has been shown to be detrimental to burn patients. Pain-generating mechanisms in burns include nociception, primary and secondary hyperalgesia and neuropathy. The clinical studies of burn pain characteristics reveal very clear-cut differences between continuous pain and pain due to therapeutic procedures which have to be treated separately. Some of the main features of burn pain are: (1) its long-lasting course, often exceeding healing time, (2) the repetition of highly nociceptive procedures which can lead to severe psychological disturbances if pain control is inappropriate. Pharmaco-therapy with opioids is the mainstay for analgesia in burned patients, but non-pharmacological techniques may be useful adjuncts. Routine pain evaluation is mandatory for efficient and safe analgesia. Special attention must be given to pain in burned children which remains too often underestimated and undertreated. More educational efforts from physicians and nursing staff are necessary to improve pain management in burned patients.

  8. Coking characteristics of reforming catalysts

    SciTech Connect

    Mieville, R.L.

    1986-08-01

    Coking rates were measured for two different ..gamma..-aluminas, each with and without platinum, under near commercial conditions using a gravimetric reactor. Coke on catalyst was characterized by a Temperature-Programmed Oxidation (TPO) technique. With a naphtha feed, coke formed on both aluminas at rates related to the respective population of ..cap alpha..-sites as measured by IR. For the corresponding Pt on alumina catalysts, coke, as measured by TPO, predominantly formed on sites associated with alumina (alumina coke), while coke associated with Pt (Pt coke), was relatively minor. With a n-heptane feed, under the same conditions, coke formation on both aluminas was much less than with the naphtha feed. However, the corresponding Pt on alumina catalysts generated comparatively more coke with a higher proportion associated with Pt. A correspondence between this proportion of Pt coke and the decline in reforming activity was observed. It is postulated that most of the coke produced during naphtha reforming with an active catalyst is formed by a reaction between ..cap alpha..-sites on alumina and certain components in the feed via a polymerization mechanism. This type of coke has minimal effect on the reforming reactivity of the catalyst. However, in n-heptane reforming, about 50% of the coke also results from precursors formed from reactions with Pt. In either case, coke associated with Pt appears to be the probable cause of deactivation. 22 references.

  9. Burning Mouth Syndrome.

    PubMed

    Kamala, K A; Sankethguddad, S; Sujith, S G; Tantradi, Praveena

    2016-01-01

    Burning mouth syndrome (BMS) is multifactorial in origin which is typically characterized by burning and painful sensation in an oral cavity demonstrating clinically normal mucosa. Although the cause of BMS is not known, a complex association of biological and psychological factors has been identified, suggesting the existence of a multifactorial etiology. As the symptom of oral burning is seen in various pathological conditions, it is essential for a clinician to be aware of how to differentiate between symptom of oral burning and BMS. An interdisciplinary and systematic approach is required for better patient management. The purpose of this study was to provide the practitioner with an understanding of the local, systemic, and psychosocial factors which may be responsible for oral burning associated with BMS, and review of treatment modalities, therefore providing a foundation for diagnosis and treatment of BMS.

  10. [Chickenpox, burns and grafts].

    PubMed

    Rojas Zegers, J; Fidel Avendaño, L

    1979-01-01

    An outbreak of chickenpox that occurred at the Burns Repair Surgery Unit, Department of Children's Surgery, Hospital R. del Río, between June and November, 1975, is reported. 27 cases of burned children were studied, including analysis of correlations of the stages and outcome of the disease (varicela), the trauma (burns) and the graft (repair surgery). As a result, the authors emphasize the following findings: 1. Burns and their repair are not aggravating factors for varicella. In a small number of cases the exanthema looked more confluent in the graft surgical areas and in the first degree burns healing spontaneously. 2. Usually there was an uneventful outcome of graft repair surgery on a varicella patient, either during the incubation period, the acme or the convalescence. 3. The fact that the outmost intensity of secondary viremia of varicella occurs before the onset of exanthemia, that is, during the late incubation period, is confirmed.

  11. Burning mouth syndrome.

    PubMed

    Nasri-Heir, Cibele

    2012-01-01

    According to the International Association for the Study of Pain, burning mouth Syndrome (BMS) is defined as a burning pain in the tongue or other oral mucous membrane in the absence of clinical signs or laboratory findings. The etiology is unknown and presents a challenge for both researchers and clinicians. The management of BMS is still not satisfactory. The prognosis is poor and the burning sensation can last for many years causing a dramatic impact on the patient's quality of life. It is important to distinguish between true BMS and symptomatic burning sensation which occurs when the burning sensation is secondary to a local or systemic pathologic condition. Currently, there are no defined diagnostic criteria for BMS. A diagnosis is usually reached by exclusion of other diseases. This may lead to misdiagnoses, presenting an obstacle to successful treatment.

  12. Children with burns referred for child abuse evaluation: Burn characteristics and co-existent injuries.

    PubMed

    Pawlik, Marie-Christin; Kemp, Alison; Maguire, Sabine; Nuttall, Diane; Feldman, Kenneth W; Lindberg, Daniel M

    2016-05-01

    Intentional burns represent a serious form of physical abuse that must be identified to protect children from further harm. This study is a retrospectively planned secondary analysis of the Examining Siblings To Recognize Abuse (ExSTRA) network data. Our objective was to describe the characteristics of burns injuries in children referred to Child Abuse Pediatricians (CAPs) in relation to the perceived likelihood of abuse. We furthermore compare the extent of diagnostic investigations undertaken in children referred to CAPs for burn injuries with those referred for other reasons. Within this dataset, 7% (215/2890) of children had burns. Children with burns were older than children with other injuries (median age 20 months vs. 10 months). Physical abuse was perceived as likely in 40.9% (88) and unlikely in 59.1% (127). Scalds accounted for 52.6% (113) and contact burns for 27.6% (60). Several characteristics of the history and burn injury were associated with a significantly higher perceived likelihood of abuse, including children with reported inflicted injury, absent or inadequate explanation, hot water as agent, immersion scald, a bilateral/symmetric burn pattern, total body surface area ≥10%, full thickness burns, and co-existent injuries. The rates of diagnostic testing were significantly lower in children with burns than other injuries, yet the yield of skeletal survey and hepatic transaminases testing were comparable between the two groups. This would imply that children referred to CAPs for burns warrant the same level of comprehensive investigations as those referred for other reasons.

  13. Epidemiology of Burn Injuries at a Newly Established Burn Care Center in Rasht

    PubMed Central

    Alavi, Cyrus Emir; Salehi, Seyed Hamid; Tolouei, Mohammad; Paydary, Koosha; Samidoust, Pirouz; Mobayen, Mohammadreza

    2012-01-01

    Background Advances in the care of burn injuries have resulted from the efforts of regional patient-based specialist teams at burn care centers. Objectives We conducted this study to assess the four-year epidemiology of burn injuries in Rasht, Iran. Materials and Methods In this cross-sectional study, medical records of 2274 burn patients, treated at Velayat hospital from January 2007 to December 2010 in Rasht, Iran, were assessed. Age, sex, level of education, occupation, severity and degree of burn, burn surface area, burn cause and outcome of patients were evaluated. Results In our study the overall mortality rate was 8.7%; 65.7% of patients were men and 34.3% were women. Mean age of patients was 31.47 ± 22.67 years. Mean Total Burn Surface Area (TBSA) was 15.24 ± 18.4. Lowest TBSA was 0.5% and highest TBSA was 100%. Significant associations were observed between age (P = 0.0001), place of residence (P = 0.004), level of education (P = 0.0001), unemployment (P = 0.0001), marital status (P = 0.021), causes of burn (P = 0.0001), TBSA (P = 0.0001) and mortality rate. In our study, no significant difference was observed between age and sex (P = 0.071). Conclusions Due to high prevalence of burn injuries in Iran, increasing the level of awareness of the society as well as adhering to safety procedures both at home and workplace is recommended via implementing effective national safety policies. PMID:24350121

  14. Nanostructured catalysts for organic transformations.

    PubMed

    Chng, Leng Leng; Erathodiyil, Nandanan; Ying, Jackie Y

    2013-08-20

    The development of green, sustainable and economical chemical processes is one of the major challenges in chemistry. Besides the traditional need for efficient and selective catalytic reactions that will transform raw materials into valuable chemicals, pharmaceuticals and fuels, green chemistry also strives for waste reduction, atomic efficiency and high rates of catalyst recovery. Nanostructured materials are attractive candidates as heterogeneous catalysts for various organic transformations, especially because they meet the goals of green chemistry. Researchers have made significant advances in the synthesis of well-defined nanostructured materials in recent years. Among these are novel approaches that have permitted the rational design and synthesis of highly active and selective nanostructured catalysts by controlling the structure and composition of the active nanoparticles (NPs) and by manipulating the interaction between the catalytically active NP species and their support. The ease of isolation and separation of the heterogeneous catalysts from the desired organic product and the recovery and reuse of these NPs further enhance their attractiveness as green and sustainable catalysts. This Account reviews recent advances in the use of nanostructured materials for catalytic organic transformations. We present a broad overview of nanostructured catalysts used in different types of organic transformations including chemoselective oxidations and reductions, asymmetric hydrogenations, coupling reactions, C-H activations, oxidative aminations, domino and tandem reactions, and more. We focus on recent research efforts towards the development of the following nanostructured materials: (i) nanostructured catalysts with controlled morphologies, (ii) magnetic nanocomposites, (iii) semiconductor-metal nanocomposites, and (iv) hybrid nanostructured catalysts. Selected examples showcase principles of nanoparticle design such as the enhancement of reactivity, selectivity

  15. Profile of self-inflicted burn patients treated at a tertiary burn center in Istanbul.

    PubMed

    Uygur, Fatih; Sever, Celalettin; Oksüz, Sinan; Duman, Haluk

    2009-01-01

    The factors and demographic features of self-inflicted burns in Eastern and Western cultures differ from each other. In this retrospective study, the authors' aim is to identify the epidemiologic features of self-inflicted burn patients treated at their Tertiary Burn Centre. The Burn Centre provides health care to a large population from Istanbul, which is located at the crossroads between Asia and Europe. The demographic data and information of 32 patients who were admitted to the GATA HEH Burn Center in Istanbul for attempted suicide were retrospectively reviewed over a 7-year period (2001-2008). Twenty-eight of the 32 patients were men, whereas the remaining four patients were women. The average age was 25.9 years. Seventeen patients had a previous history of self-harming and 22 patients were unemployed. History of a psychiatric illness was found in 20 patients. Mean total body burn surface area was 70%. The mortality rate was 43.4%. This study demonstrates that suicide attempts by burning differ from Eastern and Western cultures by factors and demographic features. It has been concluded that the solution to preventing self-inflicted burns calls for the joint efforts of physicians, psychologists, and sociologists. Furthermore, it is necessary to reinstate prevention programs and revise strategies for prevention based on the country and its culture.

  16. Ruthenium-based olefin metathesis catalysts bearing pH-responsive ligands: External control of catalyst solubility and activity

    NASA Astrophysics Data System (ADS)

    Balof, Shawna Lynn

    2011-12-01

    Sixteen novel, Ru-based olefin metathesis catalysts bearing pH responsive ligands were synthesized. The pH-responsive groups employed with these catalysts included dimethylamino (NMe2) modified NHC ligands as well as N-donor dimethylaminopyridine (DMAP) and 3-(o-pyridyl)propylidene ligands. These pH-responsive ligands provided the means by which the solubility and/or activity profiles of the catalysts produced could be controlled via acid addition. The main goal of this dissertation was to design catalyst systems capable of performing ring opening metathesis (ROMP) and ring closing metathesis (RCM) reactions in both organic and aqueous media. In an effort to quickly gain access to new catalyst structures, a template synthesis for functionalized NHC ligand precursors was designed, in addition to other strategies, to obtain ligand precursors with ancillary NMe2 groups. Kinetic studies for the catalysts produced from these precursors showed external control of catalyst solubility was afforded via protonation of the NMe2 groups of their NHC ligands. Additionally, this protonation afforded external control of catalyst propagation rates for several catalysts. This is the first known independent external control for the propagation rates of ROMP catalysts. The incorporation of pH-responsive N-donor ligands into catalyst structures also provided the means for the external control of metathesis activity, as the protonation of these ligands resulted in an increased initiation rate based on their fast and irreversible dissociation from the metal center. The enhanced external control makes these catalysts applicable to a wide range of applications, some of which have been explored by us and/or through collaboration. Three of the catalysts designed showed remarkable metathesis activity in aqueous media. These catalysts displayed comparable RCM activity in aqueous media to a class of water-soluble catalysts reported by Grubbs et al., considered to be the most active catalyst for

  17. Investigation of critical burning of fuel droplets

    NASA Technical Reports Server (NTRS)

    Allison, C. B.; Canada, G. S.; Faeth, G. M.

    1972-01-01

    Measurements were made on the burning of liquid hydrazine, MMH, and UDMH in a combustion gas environment. The experimental range of these tests involved gas temperatures of 1660-2530 K, oxygen concentrations of 0-42% by mass and droplet diameters (employing both droplets and porous spheres) of 0.11-1.91 cm. at atmospheric pressure. A simplified hybrid combustion theory was developed which was found to correlate the present results as well as the experimental measurements of other investigators. Measurements were also made of the monopropellant strand burning rates and liquid surface temperatures of a number of nitrate ester fuels and hydrazine at elevated pressures. The temperature measurements for the nitrate esters were found to be in good agreement with a theoretical model which allowed for gas solubility in the liquid phase at high pressures. Experimental results were also obtained on the burning rates and liquid surface temperatures of a number of paraffin and alcohol fuels burning in air pressures up to 72 atm. For these tests, the fuels were burned from porous spheres in a natural convection environment. Initial findings on a pressurized flat flame burner are also described as well as the design of an oscillatory combustion apparatus to test the response of burning liquid fuels.

  18. Burn size determines the inflammatory and hypermetabolic response

    PubMed Central

    Jeschke, Marc G; Mlcak, Ronald P; Finnerty, Celeste C; Norbury, William B; Gauglitz, Gerd G; Kulp, Gabriela A; Herndon, David N

    2007-01-01

    Background Increased burn size leads to increased mortality of burned patients. Whether mortality is due to inflammation, hypermetabolism or other pathophysiologic contributing factors is not entirely determined. The purpose of the present study was to determine in a large prospective clinical trial whether different burn sizes are associated with differences in inflammation, body composition, protein synthesis, or organ function. Methods Pediatric burned patients were divided into four burn size groups: <40% total body surface area (TBSA) burn, 40–59% TBSA burn, 60–79% TBSA burn, and >80% TBSA burn. Demographic and clinical data, hypermetabolism, the inflammatory response, body composition, the muscle protein net balance, serum and urine hormones and proteins, and cardiac function and changes in liver size were determined. Results One hundred and eighty-nine pediatric patients of similar age and gender distribution were included in the study (<40% TBSA burn, n = 43; 40–59% TBSA burn, n = 79; 60–79% TBSA burn, n = 46; >80% TBSA burn, n = 21). Patients with larger burns had more operations, a greater incidence of infections and sepsis, and higher mortality rates compared with the other groups (P < 0.05). The percentage predicted resting energy expenditure was highest in the >80% TBSA group, followed by the 60–79% TBSA burn group (P < 0.05). Children with >80% burns lost the most body weight, lean body mass, muscle protein and bone mineral content (P < 0.05). The urine cortisol concentration was highest in the 80–99% and 60–79% TBSA burn groups, associated with significant myocardial depression and increased change in liver size (P < 0.05). The cytokine profile showed distinct differences in expression of IL-8, TNF, IL-6, IL-12p70, monocyte chemoattractant protein-1 and granulocyte–macrophage colony-stimulating factor (P < 0.05). Conclusion Morbidity and mortality in burned patients is burn size dependent, starts at a 60% TBSA burn and is due to an

  19. Hypercoagulability after burn injury.

    PubMed

    Van Haren, Robert M; Thorson, Chad M; Valle, Evan J; Busko, Alexander M; Guarch, Gerardo A; Andrews, David M; Pizano, Louis R; Schulman, Carl I; Namias, Nicholas; Proctor, Kenneth G

    2013-07-01

    Hypercoagulability is a homeostatic response to trauma, but relatively little information is available about coagulation changes after burn injury. Therefore, we tested the hypothesis that burn patients are hypercoagulable at admission and/or during recovery. A prospective observational trial was conducted at an American Burn Association verified Burn Center. Thromboelastography (TEG) was performed on blood drawn from indwelling catheters upon admission and weekly for those who remained hospitalized. Routine and special coagulation tests were performed on stored samples. Data are expressed as median (interquartile range). Twenty-four patients (88% male) were enrolled, with a median age of 49 (20) years and a median total body surface area burn of 29% (23%); 21 experienced thermal burns (4 inhalational injuries), and 3 had electrical burns. There were no significant differences in TEG or coagulation assays between patients with thermal versus electrical burn injury, but there were significant differences between men versus women and between those with or without inhalational injury. Sixteen patients had repeat samples 1 week after intensive care unit admission. The repeat TEG was more hypercoagulable (all p < 0.05). Fibrinogen and natural anticoagulation proteins (protein C, protein S, and antithrombin III) were also increased (all p < 0.05). Two patients (8%) developed venous thromboembolism (VTE); TEG reaction time, fibrinogen, and partial thromboplastin time were decreased (all p < 0.05) at admission compared with those with no VTE. All changes occurred despite pharmacologic thromboprophylaxis. There was no significant correlation between TEG and total body surface area or between TEG and fluid balance. In general, burn patients have normal coagulation parameters at admission but become hypercoagulable during recovery. However, those who are hypercoagulable at admission may have an increased risk of VTE. Additional monitoring and/or thromboprophylaxis may be

  20. Novel platinum/KL catalysts for the aromatization of N-hexane

    NASA Astrophysics Data System (ADS)

    Jacobs, Gary

    A number of studies were conducted to understand the underlying reasons for the uniqueness of Pt/KL for its high activity and selectivity for benzene production. Catalytic screening of basic supported Pt catalysts revealed that aromatization passes through dehydrogenated intermediates, including hexenes. Pt/KL was found to more efficiently convert hexenes to benzene than nonmicroporous basic supported Pt catalysts. The role of L-zeolite was found to protect the Pt clusters from bimolecular pathways leading to the deposition of coke on the surface of the Pt. Sulfur deactivates Pt/KL by agglomeration of Pt clusters and the formation of Pt-S, breaking up Pt ensembles required for aromatization. The role of morphology of Pt inside the L-zeolite channels was found to play an important role on catalytic stability. Series of catalysts were prepared by incipient wetness and vapor phase impregnation and characterized by a variety of techniques, including H2 chemisorption, EXAFS, FTIR of adsorbed CO, MCP ring opening, and TEM and tested by both pulse and flow mode n-hexane reaction. While both catalysts exhibited small Pt clusters inside the channels of the L-zeolite, the IWI had a fraction near the surface region large enough to block channels. Under reaction, the IWI catalysts deactivated to about half the initial activity. However, VPI had Pt clusters small enough to reside in the lobes of the ellipsoid cages of the channels; these catalysts were remarkably stable. Addition of a small amount of thulium to KL was found to aid in dispersing the Pt. Using TPO, thulium was found to act a sulfur getter. Electronic modification to Pt by exchanging the zeolite cation from potassium to lithium was studied by shape resonance XANES, microcalorimetry, and pulse neopentane hydrogenolysis. Addition of lithium resulted in a shift of the Fermi level of Pt away from the antibonding state of Pt-H, strengthening the chemisorption bond. Increased hydrogenolysis rates were observed for both

  1. Burn encephalopathy in children.

    PubMed

    Mohnot, D; Snead, O C; Benton, J W

    1982-07-01

    Among 287 children with burns treated over a recent two-year period, 13 (5%) showed evidence of encephalopathy. The major clinical symptoms were an altered sensorium and seizures. The majority of symptoms began later than 48 hours after the burn and were accompanied by multiple metabolic aberrations including hypocalcemia. Three children had a relapsing course, and 1 had temporarily enlarged cerebral ventricles. Eleven children improved to normal. In the majority of instances, burn encephalopathy probably reflects central nervous system dysfunction resulting from complex metabolic, hematological, and hemodynamic abnormalities rather than from a single metabolic abnormality.

  2. Microsurgical Burn Reconstruction.

    PubMed

    Seth, Akhil K; Friedstat, Jonathan S; Orgill, Dennis P; Pribaz, Julian J; Halvorson, Eric G

    2017-10-01

    The treatment of burn-related wounds requires consideration of several factors, including defect size, available donor sites, exposure of critical structures, and the ultimate functional and aesthetic result of reconstruction. Although skin grafts and locoregional flaps are workhorses in burn reconstruction, they have inherent limitations that can directly impact reconstructive outcomes. Microsurgical free tissue transfer represents a viable option for the reconstruction of burn-related wounds in certain patients. Each anatomic region of the body has unique challenges that must be addressed to achieve a successful reconstruction. Therefore, the choice of free flap must be individualized to the wound and patients. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Chemical engineering design of CO oxidation catalysts

    NASA Technical Reports Server (NTRS)

    Herz, Richard K.

    1987-01-01

    How a chemical reaction engineer would approach the challenge of designing a CO oxidation catalyst for pulsed CO2 lasers is described. CO oxidation catalysts have a long history of application, of course, so it is instructive to first consider the special requirements of the laser application and then to compare them to the characteristics of existing processes which utilize CO oxidation catalysts. All CO2 laser applications require a CO oxidation catalyst with the following characteristics: (1) active at stoichiometric ratios of O2 and CO, (2) no inhibition by CO2 or other components of the laser environment, (3) releases no particulates during vibration or thermal cycling, and (4) long lifetime with a stable activity. In all applications, low consumption of power is desirable, a characteristic especially critical in aerospace applications and, thus, catalyst activity at low temperatures is highly desirable. High power lasers with high pulse repetition rates inherently require circulation of the gas mixture and this forced circulation is available for moving gas past the catalyst. Low repetition rate lasers, however, do not inherently require gas circulation, so a catalyst that did not require such circulation would be favorable from the standpoint of minimum power consumption. Lasers designed for atmospheric penetration of their infrared radiation utilize CO2 formed from rare isotopes of oxygen and this application has the additional constraint that normal abundance oxygen isotopes in the catalyst must not exchange with rare isotopes in the gas mixture.

  4. Microreactor for efficient catalyst evaluation

    NASA Astrophysics Data System (ADS)

    Besser, Ronald S.; Ouyang, Sean; Surangalikar, Harshal; Prevot, Michelle

    2001-09-01

    This paper describes ongoing work in the development of microreactor-based systems for applications in the chemical process industry. The microreactors discussed here are formed from silicon using robust micromachining processes to produce devices with micrometer-scale fluidic structures including passageways for the introduction and removal of gases, and a reaction zone with a thin-film catalyst. We describe experiments done to characterize these reactors for use as development tools for industrial catalytic processes in terms of catalyst screening, acquisition of rate laws, and determination of optimal process conditions. The system studied here, the reaction of a cyclic olefin (cyclohexene) with hydrogen in the presence of platinum catalyst, is a model for industrially important catalytic hydrogenation and dehydrogenation reactions.

  5. Burns at KCMC: epidemiology, presentation, management and treatment outcome.

    PubMed

    Ringo, Y; Chilonga, K

    2014-08-01

    About 90% of the global burden of burns occurs in the low and middle income countries. In Africa it is estimated that between 17,000 and 30,000 children under five die each year due to burns. In Tanzania there are no specialized burn centers. Burn patients are often managed in the general surgical wards in most hospitals. Kilimanjaro Christian Medical Centre is one of the four tertiary referral hospitals in Tanzania. This study aimed to review the epidemiology presentation management and outcome of burn patients in this challenging environment. A cross-sectional prospective study involving 41 patients was undertaken from October 2011 to April 2012. 65.9% were males. The largest age group was below 5 years (36.6%). 19.5% were epileptic. More than half of the burns were due to open flame. 80.5% had second degree burns. 56.1% had a BSA of 15% or less and 56.1% had an APACHE score of 10 or less. It was found that 73.2% of burns occurred at home. The commonest prehospital first aid applied was honey. Only 41.5% arrived in hospital within the first 24h after burn. Among the 14.6% who had skin grafting, none had early excision of burn wound. 53.7% developed wound sepsis while 24.4% developed contractures. The mortality rate was 26.8%. Children under five are the worst affected by burns. Most patients had second degree burn wounds. Inappropriate management of the burn wound started just after injury and continued even in hospital. Mortality and complication rates are high. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.

  6. Burning by prescription in chaparral

    Treesearch

    Lisle R. Green

    1981-01-01

    Prescribed burning is frequently suggested for reducing conflagration costs in chaparral. Preparation for a prescribed burn includes environmental impact reports, approval by higher levels of authority, and a burn plan. After objectives are stated, the prescription can be written. Elements of the burn prescription reflect fuel, weather, and other factors that determine...

  7. Management of burn wounds.

    PubMed

    Schiestl, Clemens; Meuli, Martin; Trop, Marija; Neuhaus, Kathrin

    2013-10-01

    Small and moderate scalds in toddlers are still the most frequent thermal injuries the pediatric surgeons have to face today. Over the last years, surgical treatment of these patients has changed in many aspects. Due to new dressing materials and new surgical treatment strategies that are particularly suitable for children, today, far better functional and aesthetic long-term results are possible. While small and moderate thermal injuries can be treated in most European pediatric surgical departments, the severely burned child must be transferred to a specialized, ideally pediatric, burn center, where a well-trained multidisciplinary team under the leadership of a (ideally pediatric) burn surgeon cares for these highly demanding patients. In future, tissue engineered full thickness skin analogues will most likely play an important role, in pediatric burn as well as postburn reconstructive surgery. Georg Thieme Verlag KG Stuttgart · New York.

  8. New Fashioned Book Burning.

    ERIC Educational Resources Information Center

    Gardner, Robert

    1997-01-01

    Reports on results of a teacher's experiment in book burning as a lesson accompanying the teaching of Ray Bradbury's "Fahrenheit 451." Discusses student reactions and the purpose of or justification for the experimental lesson. (TB)

  9. Burns Fact Sheet

    MedlinePlus

    ... the horizon for burn research? Improving methods for wound healing and tissue repair offer tremendous opportunities to enhance ... various aspects of the recovery process, such as wound healing and tissue repair. An important goal of this ...

  10. Burns (For Parents)

    MedlinePlus

    ... you drowsy, or in bed. Don't use fireworks or sparklers. Bathroom Set the thermostat on your ... For Kids For Parents MORE ON THIS TOPIC Fireworks Safety First Aid: Burns First Aid: Sunburn Sun ...

  11. Burns and Fire Safety

    MedlinePlus

    ... Mickalide A. Hot tap water legislation in the United States. J Burn Care Res . 2010; 31(6): 918-925. 13 Safe Kids Worldwide, Public Policy Department, 2005. 14 AntiScald, Inc. Available from: http:// ...

  12. New Fashioned Book Burning.

    ERIC Educational Resources Information Center

    Gardner, Robert

    1997-01-01

    Reports on results of a teacher's experiment in book burning as a lesson accompanying the teaching of Ray Bradbury's "Fahrenheit 451." Discusses student reactions and the purpose of or justification for the experimental lesson. (TB)

  13. Burn Wise Awareness Kit

    EPA Pesticide Factsheets

    Health and safety outreach materials in the form of an awareness kit. Designed specifically for state, local, and tribal air agencies working to reduce wood smoke pollution, it includes best burn tips, social media m

  14. Candidemia in major burns patients.

    PubMed

    Renau Escrig, Ana I; Salavert, Miguel; Vivó, Carmen; Cantón, Emilia; Pérez Del Caz, M Dolores; Pemán, Javier

    2016-06-01

    Major burn patients have characteristics that make them especially susceptible to candidemia, but few studies focused on this have been published. The objectives were to evaluate the epidemiological, microbiological and clinical aspects of candidemia in major burn patients, determining factors associated with a poorer prognosis and mortality. We conducted a retrospective observational study of candidemia between 1996 and 2012 in major burn patients admitted to the La Fe University Hospital, Valencia, Spain. The study included 36 episodes of candidemia in the same number of patients, 55.6% men, mean age 37.33 years and low associated comorbidity. The incidence of candidemia varied between 0.26 and 6.09 episodes/1000 days stay in the different years studied. Candida albicans was the most common species (61.1%) followed by Candida parapsilosis (27.8%). Candidemia by C. krusei, C. glabrata or C. tropicalis were all identified after 2004. Central vascular catheter (CVC) was established as a potential source of candidemia in 36.1%, followed by skin and soft tissues of thermal injury (22.2%) and urinary tract (8.3%). Fluconazole was used in 19 patients (52.7%) and its in vitro resistance rate was 13.9%. The overall mortality was 47.2%, and mortality related to candidemia was 30.6%. Factors associated with increased mortality were those related to severe infection and shock. CVC was the most usual focus of candidemia. Fluconazole was the most common antifungal drug administered. The management of candidemia in major burn patients is still a challenge. © 2016 Blackwell Verlag GmbH.

  15. The media glorifying burns: a hindrance to burn prevention.

    PubMed

    Greenhalgh, David G; Palmieri, Tina L

    2003-01-01

    The media have a profound influence on the actions of children and adults. Burns and burn prevention tend to be ignored or even mocked. The purpose of this presentation is to reveal the callousness of the media in its dealings with burns and burn prevention. Printed materials with a relationship to burns, risk of burning, or disrespect for the consequences of burns were collected. The materials were tabulated into four categories: comics, advertisements (ads), articles that made light of burns, and television shows that portrayed behavior that would risk burn injury. Most burn-related materials were found in comics or advertisements. Several comics made light of high-risk behavior with flames, scald injury, contact injury, or burns. In addition, several advertisements showed people on fire or actions that could easily lead to burns. Several articles and televisions shows portrayed high-risk behavior that, in some instances, led to copycat injuries. Flames are frequently used to sell items that target adolescent boys or young men. The high incidence injuries that frequent this population parallel the high-risk behaviors portrayed by the media. The media portrays flames and high-risk behavior for burn injury as being cool, funny, and without consequence. The use of flames on clothing and recreational equipment (skateboards, hot rods) particularly targets the high-risk adolescent male. The burn community should make the media aware of the harm it causes with its callous depiction and glorification of burns.

  16. Accidental burns during surgery.

    PubMed

    Demir, Erhan; O'Dey, Dan Mon; Pallua, Norbert

    2006-01-01

    The purpose of this report is to increase awareness of intraoperative burns during standard procedures, to discuss their possible causes and warning signs and to provide recommendations for prevention and procedures to follow after their occurrence. A total of 19 patients associated with intraoperative burn accidents were treated surgically and analyzed after a mean follow-up of 5 +/- 3.5 months. Review included retrospective patient chart analysis, clinical examination, and technical device and equipment testing. A total of 15 patients recently underwent cardiac surgery, and 4 pediatric patients recovered after standard surgical procedures. A total of 15 patients had superficial and 4 presented with deep dermal or full-thickness burns. The average injured TBSA was 2.1 +/- 1% (range, 0.5-4%). Delay between primary surgery and consultation of plastic surgeons was 4.5 +/- 3.4 days. A total of 44% required surgery, including débridment, skin grafting or musculocutaneous gluteus maximus flaps, and the remaining patients were treated conservatively. Successful durable soft-tissue coverage of the burn region was achieved in 18 patients, and 1 patient died after a course of pneumonia. Technical analysis demonstrated one malfunctioning electrosurgical device, one incorrect positioned neutral electrode, three incidents occurred after moisture under the negative electrode, eight burns occurred during surgery while fluid or blood created alternate current pathways, five accidents were chemical burns after skin preparation with Betadine solution, and in one case, the cause was not clear. The surgical team should pay more attention to the probability of burns during surgery. Early patient examination and immediate involvement of plastic and burn surgeons may prevent further complications or ease handling after the occurrence.

  17. Burn Depth Monitor

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Supra Medical Systems is successfully marketing a device that detects the depth of burn wounds in human skin. To develop the product, the company used technology developed by NASA Langley physicists looking for better ultrasonic detection of small air bubbles and cracks in metal. The device is being marketed to burn wound analysis and treatment centers. Through a Space Act agreement, NASA and the company are also working to further develop ultrasonic instruments for new medical applications

  18. Burn Depth Monitor

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Supra Medical Systems is successfully marketing a device that detects the depth of burn wounds in human skin. To develop the product, the companyused technology developed by NASA Langley physicists looking for better ultrasonic detection of small air bubbles and cracks in metal. The device is being marketed to burn wound analysis and treatment centers. Through a Space Act agreement, NASA and the company are also working to further develop ultrasonic instruments for new medical applications.

  19. Burn Depth Monitor

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Supra Medical Systems is successfully marketing a device that detects the depth of burn wounds in human skin. To develop the product, the company used technology developed by NASA Langley physicists looking for better ultrasonic detection of small air bubbles and cracks in metal. The device is being marketed to burn wound analysis and treatment centers. Through a Space Act agreement, NASA and the company are also working to further develop ultrasonic instruments for new medical applications.

  20. Smartphone applications in burns.

    PubMed

    Wurzer, Paul; Parvizi, Daryousch; Lumenta, David B; Giretzlehner, Michael; Branski, Ludwik K; Finnerty, Celeste C; Herndon, David N; Tuca, Alexandru; Rappl, Thomas; Smolle, Christian; Kamolz, Lars P

    2015-08-01

    Since the introduction of applications (apps) for smartphones, the popularity of medical apps has been rising. The aim of this review was to demonstrate the current availability of apps related to burns on Google's Android and Apple's iOS store as well as to include a review of their developers, features, and costs. A systematic online review of Google Play Store and Apple's App Store was performed by using the following search terms: "burn," "burns," "thermal," and the German word "Verbrennung." All apps that were programmed for use as medical apps for burns were included. The review was performed from 25 February until 1 March 2014. A closer look at the free and paid calculation apps including a standardized patient was performed. Four types of apps were identified: calculators, information apps, book/journal apps, and games. In Google Play Store, 31 apps were related to burns, of which 20 were calculation apps (eight for estimating the total body surface area (TBSA) and nine for total fluid requirement (TFR)). In Apple's App Store, under the category of medicine, 39 apps were related to burns, of which 21 were calculation apps (19 for estimating the TBSA and 17 for calculating the TFR). In 19 out of 32 available calculation apps, our study showed a correlation of the calculated TFR compared to our standardized patient. The review demonstrated that many apps for medical burns are available in both common app stores. Even free available calculation apps may provide a more objective and reproducible procedure compared to manual/subjective estimations, although there is still a lack of data security especially in personal data entered in calculation apps. Further clinical studies including smartphone apps for burns should be performed. Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.

  1. Burning mouth syndrome.

    PubMed

    Thoppay, Jaisri R; De Rossi, Scott S; Ciarrocca, Katharine N

    2013-07-01

    Burning mouth syndrome (BMS) is a chronic condition that is characterized by burning symptoms of the oral mucosa without obvious clinical examination findings. This syndrome has complex characteristics, but its cause remains largely enigmatic, making treatment and management of patients with BMS difficult. Despite not being accompanied by evident organic changes, BMS can significantly reduce the quality of life for such patients. Therefore, it is incumbent on dental professionals to diagnose and manage patients with BMS as a part of comprehensive care.

  2. Burn care in South Africa: a micro cosmos of Africa.

    PubMed

    Rode, H; Cox, S G; Numanoglu, A; Berg, A M

    2014-07-01

    Burn injuries in Africa are common with between 300,000 and 17.5 million children under 5 years sustaining burn injuries annually, resulting in a high estimated fatality rate. These burns are largely environmentally conditioned and therefore preventable. The Western Cape Province in South Africa can be regarded as a prototype of paediatric burns seen on the continent, with large numbers, high morbidity and mortality rates and an area inclusive of all factors contributing to this extraordinary burden of injury. Most of the mechanisms to prevent burns are not easily modified due to the restraint of low socio-economic homes, overcrowding, unsafe appliances, multiple and complex daily demands on families and multiple psycho-social stressors. Children <4 years are at highest risk of burns with an average annual rate of 6.0/10,000 child-years. Burn care in South Africa is predominantly emergency driven and variable in terms of organization, clinical management, facilities and staffing. Various treatment strategies were introduced. The management of HIV positive children poses a problem, as well as the conflict of achieving equity of burn care for all children. Without alleviating poverty, developing minimum standards for housing, burn education, safe appliances and legislation, we will not be able to reduce the "curse of poor people" and will continue to treat the consequences.

  3. Lewis Base Catalysts 6: Carbene Catalysts

    PubMed Central

    Moore, Jennifer L.

    2013-01-01

    The use of N-heterocyclic carbenes as catalysts for organic transformations has received increased attention in the past 10 years. A discussion of catalyst development and nucleophilic characteristics precedes a description of recent advancements and new reactions using N-heterocyclic carbenes in catalysis. PMID:21494949

  4. [Invasive yeast infections in severely burned patients].

    PubMed

    Renau, Ana Isabel; García-Vidal, Carolina; Salavert, Miguel

    2016-01-01

    Currently, there are few studies on candidaemia in the severely burned patient. These patients share the same risk factors for invasive fungal infections as other critically ill patients, but have certain characteristics that make them particularly susceptible. These include the loss of skin barrier due to extensive burns, fungal colonisation of the latter, and the use of hydrotherapy or other topical therapies (occasionally with antimicrobials). In addition, the increased survival rate achieved in recent decades in critically burned patients due to the advances in treatment has led to the increase of invasive Candida infections. This explains the growing interest in making an earlier and more accurate diagnosis, as well as more effective treatments to reduce morbidity and mortality of candidaemia in severe burned patients. A review is presented on all aspects of the burned patient, including the predisposition and risk factors for invasive candidiasis, pathogenesis of candidaemia, underlying immunodeficiency, local epidemiology and antifungal susceptibility, evolution and prognostic factors, as well as other non-Candida yeast infections. Finally, we include specific data on our local experience in the management of candidaemia in severe burned patients, which may serve to quantify the problem, place it in context, and offer a realistic perspective. Copyright © 2016 Asociación Española de Micología. Publicado por Elsevier España, S.L.U. All rights reserved.

  5. Deactivation of Oxidation Catalysts

    DTIC Science & Technology

    1991-05-01

    the fresh catalyst . The loss in chromium may be related to the formation of volatile chromium oxychlorde which vaporizes from the catalyst . It is...CeO2 only marginally improved the thtrmal stability. The addition of 2% water vapor inhibited the oxidation of ethanol for all three copper catalysts ...original activity. Field tests of a copper chromite catalyst on process gas containing H2S, methyl mercaptan, n-aldehydes, and furfural showed

  6. Diabetes and burns: retrospective cohort study.

    PubMed

    McCampbell, Beth; Wasif, Nabil; Rabbitts, Angela; Staiano-Coico, Lisa; Yurt, Roger W; Schwartz, Suzanne

    2002-01-01

    Burn injuries are often associated with multisystemic complications, even in otherwise healthy individuals. It is therefore intuitive that for the diabetic patient, the underlying pathophysiologic alterations in vascular supply, peripheral neuropathy, and immune function could have a profoundly devastating impact on patient outcome. The effects of diabetes on morbidity and mortality of the burn-injured patient have not been examined in great detail. The purpose of this retrospective study was to compare clinical outcomes between diabetic and nondiabetic burn patients. We reviewed the charts of 181 diabetic (DM) and 190 nondiabetic (nDM) patients admitted with burns between January 1996 and May 2000, matched by sex and date of admission. Burn cause and size, time to presentation, clinical course, and outcomes were evaluated. Because age was a factor, the analysis was done by three age groups: younger than 18 years, 18 to 65 years, and older than 65 years. Of patients 18 to 65 years, 51% (98/191) were diabetic, whereas 84% (81/96) of those older than 65 and only 4% (3/85) of patients younger than 18 were diabetic. Because of the disproportion in numbers of diabetics compared with nondiabetics in the younger than 18 and older than 65 years-old groups, these patients will not be discussed. Diabetics were more likely to incur scald injury from tub or shower water rather than hot fluid spills (33% DM vs 15% nDM; P < or = 0.01), and have a delayed presentation (45 vs 23%; P = 0.00001). There was no difference in total burn size in all groups. Diabetics in the 18 to 65 years group had a higher rate of full-thickness burns (51 vs 31%; P = 0.025), skin grafts (50 vs 28%; P = 0.01) and burn-related procedures (57 vs 32%; P = 0.001), infections (65 vs 51%; P = 0.05), and longer lengths of stay (23 vs 12 days; P = 0.0001). Although there was no statistically significant difference in incidence of specific infections, the rates of cellulitis, wound infection, urinary tract

  7. The Burns Registry of Australia and New Zealand: progressing the evidence base for burn care.

    PubMed

    Cleland, Heather; Greenwood, John E; Wood, Fiona M; Read, David J; Wong She, Richard; Maitz, Peter; Castley, Andrew; Vandervord, John G; Simcock, Jeremy; Adams, Christopher D; Gabbe, Belinda J

    2016-03-21

    Analysis of data from the Burns Registry of Australia and New Zealand (BRANZ) to determine the extent of variation between participating units in treatment and in specific outcomes during the first 4 years of its operation. BRANZ, an initiative of the Australian and New Zealand Burn Association, is a clinical quality registry developed in accordance with the Australian Commission on Safety and Quality in Healthcare national operating principles. Patients with burn injury who fulfil pre-defined criteria are transferred to and managed in designated burn units. There are 17 adult and paediatric units in Australia and New Zealand that manage almost all patients with significant burn injury. Twelve of these units treat adult patients. Data on 7184 adult cases were contributed by ten acute adult burn units to the registry between July 2010 and June 2014.Major outcomes: In-hospital mortality, hospital length of stay, skin grafting rates, and rates of admission to intensive care units. Considerable variations in unit profiles (including numbers of patients treated), in treatment and in outcomes were identified. Despite the highly centralised delivery of care to patients with severe or complex burn injury, and the relatively small number of specialist burn units, we found significant variation between units in clinical management and in outcomes. BRANZ data from its first 4 years of operation support its feasibility and the value of further development of the registry. Based on these results, the focus of ongoing research is to improve understanding of the reasons for variations in practice and of their effect on outcomes for patients, and to develop evidence-informed clinical guidelines for burn management in Australia and New Zealand.

  8. Epidemiological and cost analysis of burn injuries admitted to the emergency department of a tertiary burn center.

    PubMed

    Eser, Tolga; Kavalci, Cemil; Aydogan, Cem; Kayipmaz, Afsin Emre

    2016-01-01

    Burn injury is an emergency medical condition that rapidly develops as a result of tissue exposure to electrical, chemical or thermal energy. Therefore, its treatment usually begins at the emergency department. In this study we aimed to perform an epidemiological analysis of burn injuries presenting to the emergency department of a tertiary burn center, and factors affecting the cost of their medical care. Patients who presented to Baskent University Ankara Hospital Adult Emergency Department with burn injuries between January 2012 and December 2014 were studied for age, sex, time of admission, type of burn injury, clinical prognosis, mortality rate, percent burn area, and total cost of care. A total of 264 patients were enrolled. Chi square test was used for the comparison of categorical variables. Non-parametric tests were used for the comparison of continuous variables. This study included 179 (67.8 %) women and 85 (32.2 %) men. The most common types of burn injuries were hot water burns and scalding. Eleven point seven percent of the patients sustained burn injuries in occupational accidents. 95.1 % of the patients were discharged from the emergency and 4.5 % of them were hospitalized. Only 1 (0.4 %) patient died. There was no significant difference between patient outcomes (discharge vs. hospital admission) with respect to the cost of care (p = 0.846) No significant difference was found between the cost of care of surgical and non-surgical management of burn injuries (p = 0.206). No significant difference was found between the costs of care of different types of burn injuries (p = 0.053). There was a significant difference between burn degrees with respect to the cost of care (p = 0.038). A significant difference was found between the costs of care of patients with a percent burn area of less than 10 % and those with a percent burn area of more than 10 % (p < 0.001), indicating that as percent burn area increased, a proportional increase

  9. Fractional factorial study of HCN removal over a 0.5% Pt/Al₂O₃ catalyst: effects of temperature, gas flow rate, and reactant partial pressure

    SciTech Connect

    Zhao, Haibo; Tonkyn, Russell G.; Barlow, Stephan E.; Peden, Charles HF.; Koel, Bruce E.

    2006-01-07

    Fractional factorial design was used to determine which factors have significant effects on the HCN (hydrogen cyanide) oxidation reaction over 0.5% Pt/Al?O? under lean conditions. We conclude that the reaction temperature and gas-hourly space velocity (GHSV) have significant effects on the HCN conversion, while no significant effects are caused by the presence of either NO (nitric oxide) or C?H? (propene). A central composite design was used to study the effects of temperature and GHSV on HCN conversion, C?H? conversion and NOx selectivity. Based on a second polynomial equation model, regression analysis was used to study the significance of each variable term and derive equations for each response. Our results show that HCN conversion was significantly affected by temperature (X3), GHSV (X4), a temperature polynomial term (X32), and a temperature and GHSV interaction term (X3X4). HCN conversion decreased with increasing values of GHSV and increased with increasing temperature, up to a transition temperature that depends on the GHSV value. The variables of temperature (X3), GHSV (X4), and the temperature polynomial term (X32) have significant effects on both C?H? conversion and NOx selectivity, but in these two cases the interaction of temperature and GHSV was not significant. Contour plots of HCN conversion, C?H? conversion, and NOx selectivity versus temperature and GHSV were constructed from an analysis of the measured data, and these plots can be utilized to estimate HCN conversion, C?H? conversion, and NOx selectivity over the range of temperatures and GHSV investigated. Optimum catalyst operation is described by high HCN conversion and low NOx selectivity. These results show C and o that the highest HCN conversion was achieved at temperatures above 250 relatively low GHSV values, while low NOx selectivity was best achieved at a C.o temperature of 215

  10. Prelife catalysts and replicators

    PubMed Central

    Ohtsuki, Hisashi; Nowak, Martin A.

    2009-01-01

    Life is based on replication and evolution. But replication cannot be taken for granted. We must ask what there was prior to replication and evolution. How does evolution begin? We have proposed prelife as a generative system that produces information and diversity in the absence of replication. We model prelife as a binary soup of active monomers that form random polymers. ‘Prevolutionary’ dynamics can have mutation and selection prior to replication. Some sequences might have catalytic activity, thereby enhancing the rates of certain prelife reactions. We study the selection criteria for these prelife catalysts. Their catalytic efficiency must be above certain critical values. We find a maintenance threshold and an initiation threshold. The former is a linear function of sequence length, and the latter is an exponential function of sequence length. Therefore, it is extremely hard to select for prelife catalysts that have long sequences. We compare prelife catalysis with a simple model for replication. Assuming fast template-based elongation reactions, we can show that replicators have selection thresholds that are independent of their sequence length. Our calculation demonstrates the efficiency of replication and provides an explanation of why replication was selected over other forms of prelife catalysis. PMID:19692408

  11. A 10-year experience with major burns from a non-burn intensive care unit.

    PubMed

    Ibarra Estrada, Miguel Ángel; Chávez Peña, Quetzalcóatl; García Guardado, Dante Ismael; López Pulgarín, José Arnulfo; Aguirre Avalos, Guadalupe; Corona Jiménez, Federico

    2014-09-01

    The aim of this study was to review clinical data and outcomes of patients with burns in a Mexican non-burn intensive care unit (ICU). We did a retrospective analysis of our single-centre database of burn patients admitted to the ICU in the Hospital Civil Fray Antonio Alcalde (University Hospital). The sample was divided for analysis into two groups according to the outcome 'death' or 'discharge' from ICU. Overall mortality was 58.2%, without a decreasing trend in mortality rates through the years. We identified the presence of third-degree burns (odds ratio (OR) 1.5, p=0.003), and >49% total burned surface area (TBSA; OR 3.3, p≤0.001) was associated with mortality. Mean age was higher in deceased patients (38.2 years vs. 31.3 years, p=0.003) as was the TBSA (62.8% vs. 36.4%, p≤0.001). At multivariate analysis, inhalation injury was not associated with increased mortality, but it was with more mechanical ventilation days. Early surgical debridement/cleansing was performed in most patients; however, the mean of the procedures was 1.7 per patient in both groups. We identified significant factors associated with mortality. These variables and prognosis from non-burn ICUs differ broadly compared with burn intensive care units (BICUs); thus, more structured, multidisciplinary and specialised treatment strategies are still needed. Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.

  12. Burn-related factors affecting anxiety, depression and self-esteem in burn patients: an exploratory study.

    PubMed

    Jain, M; Khadilkar, N; De Sousa, A

    2017-03-31

    Burns are physically, psychologically and economically challenging injuries, and the factors leading to them are many and under-studied. The aim of the current study was to assess level of anxiety, depression and self-esteem in burn patients, and look at various burn-related variables that affect them. This cross-sectional study included 100 patients with burn injuries admitted to a tertiary care private hospital in an urban metropolis in India. The patients were assessed for anxiety, depression and self-esteem using the Hamilton anxiety rating scale, Hamilton depression rating scale and Rosenberg self-esteem scale respectively. Assessment was carried out within 2-8 weeks of injury following medical stabilization. The data was tabulated and statistically analyzed. The study sample was predominantly male (54%), married (69%), with a mean age of 34.1 ± 10.8 years. Accidental burns (94%) were the most common modality of injury. The majority (46%) suffered burns involving 20-59% total body surface area (TBSA), and facial burns were present (57%). No significant association was found between TBSA and anxiety, depression or self-esteem, and the same was true for facial burns. Deep burns, however, were significantly associated with anxiety (p=0.03) and depression (p=0.0002). High rates of anxiety and depression are associated with burn injuries and related to burn depth. Adjustment and recovery in these patients depends on various other factors like the patient's psychological status, nature/extent of the injury and ensuing medical care. Further research is warranted to reveal the magnitude and predictors of psychological problems in burn patients.

  13. Catalyst by Design

    SciTech Connect

    Narula, Chaitanya Kumar; DeBusk, Melanie Moses

    2014-01-01

    The development of new catalytic materials is still dominated by trial and error methods. Although it has been successful, the empirical development of catalytic materials is time consuming and expensive with no guarantee of success. In our laboratories, we are developing a comprehensive catalysts by design that involves state-of-the-art first principle density functional theory calculations, experimental design of catalyst sites, and sub- ngstr m resolution imaging with an aberration-corrected electron microscope to characterize the microstructure. In this chapter, we focus on supported platinum cluster catalyst systems which are one of the most important industrial catalysts and attempt to demonstrate the feasibility of the catalyst by design concept.

  14. Epidemiology and financial implications of self-inflicted burns.

    PubMed

    George, S; Javed, M; Hemington-Gorse, S; Wilson-Jones, N

    2016-02-01

    The cost of the treatment of burns is high especially in self-inflicted burns with prolonged treatment. We performed a retrospective review of the self-inflicted burns at our regional burns centre to determine the costs incurred in their management and to identify factors which could reduce the financial burden in the future. The data was collected retrospectively of all the inpatient and outpatient self-inflicted burns presenting to our regional burns centre in the year 2011. Twenty one patients (out of a total of 870 patients) presented with self-inflicted burns to our centre in 2011. Five (23.8%) were major burns with an average of 53.2% Total Body Surface Area (TBSA) and 16 (76.2%) were minor burns with an average of 0.5% TBSA. 11 (52.4%) patients had flame burns including 4 self-immolation burns. The mortality rate was 4.8% (n=1). Five (23.8%) patients underwent surgical treatment. Seven (33.3%) patients were treated in intensive care and with average stay of 46.85 days. Critical care and theatre attendances made up most of the costs with average ICU stay per patient calculated at £313,131/day. The total cost of all 21 patients was £1,581,856. Burns are preventable injuries, early detection and intervention in patients with propensity to self-inflict burns can possibly reduce the costs of treatment in the future. Copyright © 2015 Elsevier Ltd and ISBI. All rights reserved.

  15. Effect of carbachol on intestinal mucosal blood flow, activity of Na+-K+-ATPase, expression of aquaporin-1, and intestinal absorption rate during enteral resuscitation of burn shock in rats.

    PubMed

    Bao, Chengmei; Hu, Sen; Zhou, Guoyong; Tian, Yijun; Wu, Yan; Sheng, Zhiyong

    2010-01-01

    /CAR group, the levels of these parameters were significantly increased compared with scald groups (P < .05). The results indicate that CAR promotes intestinal absorption rate of water and Na by improving IMBF, ATPase activity, and AQP-1 expression in gut mucosa during resuscitation with enteral GES of burn shock in rats.

  16. Uncoupled skeletal muscle mitochondria contribute to hypermetabolism in severely burned adults

    PubMed Central

    Herndon, David N.; Børsheim, Elisabet; Chao, Tony; Reidy, Paul T.; Borack, Michael S.; Rasmussen, Blake B.; Chondronikola, Maria; Saraf, Manish K.; Sidossis, Labros S.

    2014-01-01

    Elevated metabolic rate is a hallmark of the stress response to severe burn injury. This response is mediated in part by adrenergic stress and is responsive to changes in ambient temperature. We hypothesize that uncoupling of oxidative phosphorylation in skeletal muscle mitochondria contributes to increased metabolic rate in burn survivors. Here, we determined skeletal muscle mitochondrial function in healthy and severely burned adults. Indirect calorimetry was used to estimate metabolic rate in burn patients. Quadriceps muscle biopsies were collected on two separate occasions (11 ± 5 and 21 ± 8 days postinjury) from six severely burned adults (68 ± 19% of total body surface area burned) and 12 healthy adults. Leak, coupled, and uncoupled mitochondrial respiration was determined in permeabilized myofiber bundles. Metabolic rate was significantly greater than predicted values for burn patients at both time points (P < 0.05). Skeletal muscle oxidative capacity, citrate synthase activity, a marker of mitochondrial abundance, and mitochondrial sensitivity to oligomycin were all lower in burn patients vs. controls at both time points (P < 0.05). A greater proportion of maximal mitochondrial respiration was linked to thermogenesis in burn patients compared with controls (P < 0.05). Increased metabolic rate in severely burned adults is accompanied by derangements in skeletal muscle mitochondrial function. Skeletal muscle mitochondria from burn victims are more uncoupled, indicating greater heat production within skeletal muscle. Our findings suggest that skeletal muscle mitochondrial dysfunction contributes to increased metabolic rate in burn victims. PMID:25074988

  17. Uncoupled skeletal muscle mitochondria contribute to hypermetabolism in severely burned adults.

    PubMed

    Porter, Craig; Herndon, David N; Børsheim, Elisabet; Chao, Tony; Reidy, Paul T; Borack, Michael S; Rasmussen, Blake B; Chondronikola, Maria; Saraf, Manish K; Sidossis, Labros S

    2014-09-01

    Elevated metabolic rate is a hallmark of the stress response to severe burn injury. This response is mediated in part by adrenergic stress and is responsive to changes in ambient temperature. We hypothesize that uncoupling of oxidative phosphorylation in skeletal muscle mitochondria contributes to increased metabolic rate in burn survivors. Here, we determined skeletal muscle mitochondrial function in healthy and severely burned adults. Indirect calorimetry was used to estimate metabolic rate in burn patients. Quadriceps muscle biopsies were collected on two separate occasions (11 ± 5 and 21 ± 8 days postinjury) from six severely burned adults (68 ± 19% of total body surface area burned) and 12 healthy adults. Leak, coupled, and uncoupled mitochondrial respiration was determined in permeabilized myofiber bundles. Metabolic rate was significantly greater than predicted values for burn patients at both time points (P < 0.05). Skeletal muscle oxidative capacity, citrate synthase activity, a marker of mitochondrial abundance, and mitochondrial sensitivity to oligomycin were all lower in burn patients vs. controls at both time points (P < 0.05). A greater proportion of maximal mitochondrial respiration was linked to thermogenesis in burn patients compared with controls (P < 0.05). Increased metabolic rate in severely burned adults is accompanied by derangements in skeletal muscle mitochondrial function. Skeletal muscle mitochondria from burn victims are more uncoupled, indicating greater heat production within skeletal muscle. Our findings suggest that skeletal muscle mitochondrial dysfunction contributes to increased metabolic rate in burn victims. Copyright © 2014 the American Physiological Society.

  18. Spatiotemporal Organization of Catalysts Driven by Enhanced Diffusion.

    PubMed

    Weistuch, C; Pressé, S

    2017-09-27

    Recently, both microfluidic and fluorescence correlation spectroscopy experiments have revealed that diffusion coefficients of active biological catalysts (enzymes) rise proportionately to their catalytic rate. Similar effects have also been observed for active material catalysts, such as platinum nanocatalysts in hydrogen peroxide solution. While differences in diffusion coefficients have recently been cleverly exploited to spatially separate active from inactive catalysts, here we investigate the consequences of these novel findings on the spatiotemporal organization of catalysts. In particular, we show that chemical reactions-such as coupled catalytic reactions-may drive effective attraction or repulsion between catalysts which in turn drives their spatiotemporal organization. This, we argue, may have implications for internal cell signaling.

  19. Process of activation of a palladium catalyst system

    SciTech Connect

    Sobolevskiy, Anatoly; Rossin, Joseph A.; Knapke, Michael J.

    2011-08-02

    Improved processes for activating a catalyst system used for the reduction of nitrogen oxides are provided. In one embodiment, the catalyst system is activated by passing an activation gas stream having an amount of each of oxygen, water vapor, nitrogen oxides, and hydrogen over the catalyst system and increasing a temperature of the catalyst system to a temperature of at least 180.degree. C. at a heating rate of from 1-20.degree./min. Use of activation processes described herein leads to a catalyst system with superior NOx reduction capabilities.

  20. Socioeconomic status, gender, and burn injury: A retrospective review.

    PubMed

    Dissanaike, Sharmila; Ha, Daniel; Mitchell, Diana; Larumbe, Eneko

    2017-10-01

    Burn injury rates appear to be influenced by socioeconomic status (SES) and gender globally, but the impact of poverty and gender on burn injury has not been studied in a developed country. This study was a retrospective chart review conducted at a regional burn center in the Southwest US that included 340 patients with TBSA burns >15%. SES was determined using zip code and US census data. The distribution of mechanism of injury was significantly different by gender (χ(2)(6) = 36.14, p < 0001), but not significantly different by SES (χ(2)(12) = 19.68, p = 0.073). Burn rates in women was found to have a significant and linear increase (χ(2) = 13.8513, p = 0.001) with increasing poverty. Women had higher frequencies of being burned at home, and men had higher frequencies of being burned at work. While poverty did not appear to increase the risk of burn injury overall in a mixed population, it was associated with a significant increase in the risk of burn injury in women. Thus, strategies for decreasing risk factors should be targeted toward low SES females and the working male. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Epidemiology of Burns in Rural Bangladesh: An Update.

    PubMed

    He, Siran; Alonge, Olakunle; Agrawal, Priyanka; Sharmin, Shumona; Islam, Irteja; Mashreky, Saidur Rahman; Arifeen, Shams El

    2017-04-05

    Each year, approximately 265,000 deaths occur due to burns on a global scale. In Bangladesh, around 173,000 children under 18 sustain a burn injury. Since most epidemiological studies on burn injuries in low and middle-income countries are based on small-scale surveys or hospital records, this study aims to derive burn mortality and morbidity measures and risk factors at a population level in Bangladesh. A household survey was conducted in seven rural sub-districts of Bangladesh in 2013 to assess injury outcomes. Burn injuries were one of the external causes of injury. Epidemiological characteristics and risk factors were described using descriptive as well as univariate and multivariate logistic regression analyses. The overall mortality and morbidity rates were 2 deaths and 528 injuries per 100,000 populations. Females had a higher burn rate. More than 50% of injuries were seen in adults 25 to 64 years of age. Most injuries occurred in the kitchen while preparing food. 88% of all burns occurred due to flame. Children 1 to 4 years of age were four times more likely to sustain burn injuries as compared to infants. Age-targeted interventions, awareness of first aid protocols, and improvement of acute care management would be potential leads to curb death and disability due to burn injuries.

  2. Analysis of 1089 burn patients in province of Kurdistan, Iran.

    PubMed

    Groohi, Bahram; Alaghehbandan, Reza; Lari, Abdolaziz Rastegar

    2002-09-01

    Burn injuries still produce a significant morbidity and mortality in Iran. This study was carried out to analyze the epidemiology, mortality, and current etiological factors of 1089 burn patients in the province of Kurdistan in the west of Iran during the 6 years from 21 March 1994 to 20 March 2000. There were two burn centers in Kurdistan, serving 1.4 million people in an area of 28,000 km(2). The incidence rate of burn hospitalization was 13.5 per 100,000 person-years. The median age was 18 years with 58% of the patients under 20 years. The median Body Surface Area (BSA) burned was 40%. Incidence rate of burns for females was 18 per 100,000 person-years and 9.1 per 100,000 person-years for males (P((2))<0.000001). Also there was a statistically significant association between mortality rate and age groups/gender/BBS (P((2))<0.000001). Flame was the most common type of burn (694/1089, 63.7%). There was also a significant correlation between the age groups and types of burn (P((2))<0.000001). Ninety-one percent (991/1089) of the burns were unintentional (12.3 per 100,000 person-years), while suicide attempts by burning for the population aged 13 and older accounted for 12.7% (98/771) (2 per 100,000 person-years). The mortality rate was 4.5 per 100,000 person-years. The study results provide a valuable baseline by which to assess future efforts directed toward the prevention of burn injuries in Kurdistan.

  3. Electrical burns: Highlights from a 5-year retrospective analysis.

    PubMed

    Kurt, Alper; Yıldırım, Kamil; Yağmur, Çağlayan; Kelahmetoğlu, Osman; Aslan, Ozan; Gümüş, Murat; Güneren, Ethem

    2016-05-01

    Electrical burns are the third most common cause of burn injuries, after scald and flame burns. In spite of decreasing mortality rates as advancements are made in treatment modalities and medical equipment, significant complications and socioeconomic consequences still accompany electrical burns. Analyzed in the present study were data from patients hospitalized for electrical burns between 2008 and 2012 in the Samsun Training and Research Hospital, the only burn care center in the Black Sea region of Turkey. Data from 94 patients (84 males, 10 females) hospitalized for electrical burns between 2008 and 2012 were retrospectively evaluated. Patient age, gender, occupation, presence of coexisting trauma, burn degree, burned percentage of total body surface area (TBSA), voltage of the electric current (low or high), medical cost (per day and total), and infection rates were analyzed. Mean patient age was 26.4±13.2 years. Ten patients were female (10.6%) and 84 were male (89.4%). High-voltage burns were sustained by 47 patients (50%) and low-voltage burns by 42 (44.7%); the remaining 5 were flash burns. Mean burned TBSA was 21.8±19.8% in high-voltage injuries and 11.9±6.9% in low-voltage injuries. Seven patients had accompanying soft tissue lacerations, major bone fractures, or epidural hematomas. Findings of infection were encountered in 31 patients (32.9%), and appropriate treatments were initiated according to culture results. Mean duration of hospitalization was 21.3±19.8 days in patients with high-voltage burns and 8.6±6.2 days in patients with low-voltage burns. Mean hospital stay was 2.5-fold longer, and total medical costs were 4-fold higher in patients with high-voltage burns. Young adult males who were injured in industrial accidents constituted the majority of high-voltage burn patients. Incidence of these injuries may be reduced by improvements in training regarding the safe use of electrical devices, and correct installation and safe maintenance of

  4. Predictors of muscle protein synthesis after severe pediatric burns

    USDA-ARS?s Scientific Manuscript database

    Objectives: Following a major burn, muscle protein synthesis rate increases but in most patients, this response is not sufficient to compensate the also elevated protein breakdown. Given the long-term nature of the pathophysiologic response to burn injury, we hypothesized that skeletal muscle prot...

  5. System for reactivating catalysts

    SciTech Connect

    Ginosar, Daniel M.; Thompson, David N.; Anderson, Raymond P.

    2010-03-02

    A method of reactivating a catalyst, such as a solid catalyst or a liquid catalyst is provided. The method comprises providing a catalyst that is at least partially deactivated by fouling agents. The catalyst is contacted with a fluid reactivating agent that is at or above a critical point of the fluid reactivating agent and is of sufficient density to dissolve impurities. The fluid reactivating agent reacts with at least one fouling agent, releasing the at least one fouling agent from the catalyst. The at least one fouling agent becomes dissolved in the fluid reactivating agent and is subsequently separated or removed from the fluid reactivating agent so that the fluid reactivating agent may be reused. A system for reactivating a catalyst is also disclosed.

  6. [Burn child specificity].

    PubMed

    Plancq, M C; Goffinet, L; Duquennoy-Martinot, V

    2016-10-01

    Burn is still a frequent accident in children and particularly occurs in young children under 4years. The majority were caused by hot liquids (scalds) with mixed-dermal burns and is commonly treated conservatively with surgery performed at 10-15 days post-injury after healing of superficial burn. Patients with burns greater than 10% need early fluid resuscitation and adequate nutritional support to avoid deepening with infection, improve healing and survival. Hypovolemic shock could be very abrupt in children. Prophylactic prevention of infection and optimization of healing before 21 days improve quality of scar. Management with rehabilitation team is more important in children than in adults because hypertrophic scar and retraction can restrain growth and function particularly for palmar hand burns occurring at the beginning of walking. Follow-up is essential during the growth to assess scar tension requiring secondary surgery. Better knowledge of injury mechanisms should facilitate education and prevention programs and decrease the incidence. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  7. Financial burden of burn injuries in iran: a report from the burn registry program

    PubMed Central

    Karimi, H.; Motevalian, S.A.; Momeni, M.; Ghadarjani, M.

    2015-01-01

    Summary Understanding the cost of burn treatment is very important for patients, their families, governmental authorities and insurance companies. It alleviates patient and familial stress, provides a framework for better use of resources, and facilitates better performance between burn centers. Hospital burn costs can provide a basis for authorities to budget for acute burn treatment, for further management of chronic complications, and for planning prevention and public educational programs in Iran. To identify costs we used data from our burn registry program. Over the two-year assessment period, we treated roughly 28,700 burn patients, 1,721 of whom were admitted, with a mortality rate of 5.9%. The male to female ratio was 1.7:1 (63% male; 37% female). Flame burns were most frequent (49.8%) followed by scalds (35.7%). Mean hospital stay was 14.41 days (range 0-64 days). Mean TBSA was 17.39%. Skin grafts were carried out in 65.4% of the patients, with a mean of 5.2 surgeries per patient. The total cost of all patient admissions over the two years was US$ 4,835,000. The maximum treatment cost for one patient was US$ 91,000. The mean cost per patient was US$ 2,810 (29,500,000 Rials). The mean cost for each percent of burn was US$ 162. The mean cost for a one-day stay in hospital was US$ 195. The mean cost of each operation was US$ 540. Patients who contracted infections endured longer hospital stays, meaning increased costs of US$ 195 per day. With comparable outcome and results, the cost of burn treatment in Iran is cheaper than in the US and Europe PMID:27777552

  8. Financial burden of burn injuries in iran: a report from the burn registry program.

    PubMed

    Karimi, H; Motevalian, S A; Momeni, M; Ghadarjani, M

    2015-12-31

    Understanding the cost of burn treatment is very important for patients, their families, governmental authorities and insurance companies. It alleviates patient and familial stress, provides a framework for better use of resources, and facilitates better performance between burn centers. Hospital burn costs can provide a basis for authorities to budget for acute burn treatment, for further management of chronic complications, and for planning prevention and public educational programs in Iran. To identify costs we used data from our burn registry program. Over the two-year assessment period, we treated roughly 28,700 burn patients, 1,721 of whom were admitted, with a mortality rate of 5.9%. The male to female ratio was 1.7:1 (63% male; 37% female). Flame burns were most frequent (49.8%) followed by scalds (35.7%). Mean hospital stay was 14.41 days (range 0-64 days). Mean TBSA was 17.39%. Skin grafts were carried out in 65.4% of the patients, with a mean of 5.2 surgeries per patient. The total cost of all patient admissions over the two years was US$ 4,835,000. The maximum treatment cost for one patient was US$ 91,000. The mean cost per patient was US$ 2,810 (29,500,000 Rials). The mean cost for each percent of burn was US$ 162. The mean cost for a one-day stay in hospital was US$ 195. The mean cost of each operation was US$ 540. Patients who contracted infections endured longer hospital stays, meaning increased costs of US$ 195 per day. With comparable outcome and results, the cost of burn treatment in Iran is cheaper than in the US and Europe.

  9. Pediatric burns mortality risk factors in a developing country’s tertiary burns intensive care unit

    PubMed Central

    Agbenorku, Pius; Agbenorku, Manolo; Fiifi-Yankson, Papa Kwesi

    2013-01-01

    Aim: This study aimed at identifying risk factors related to pediatric burns mortality in a middle income country such as Ghana. Methods: The data for the three years retrospective study (May 2009 – April 2012) was obtained from the pediatric burn admissions records and patients’ folders of the Reconstructive Plastic Surgery & Burns Unit (RPSBU), Komfo Anokye Teaching Hospital (KATH), Ghana. Data retrieved included: Demographic features, Total Burned Surface Area (TBSA) incurred; Aetiology of burns; Duration of the admission; Outcome of admission; Part of the body affected and Cost incurred. Ethical approval for this study was obtained from the KNUST-SMS/KATH Committee on Human Research, Publications and Ethics. Data analyses were performed with SPSS 17.0 version. Results: Information on 197 patients was completely retrieved for the study. Burns mortality rate for the study was identified to be 21.3% (N=42). The mean age of the 42 dead patients was 3.7±0.3 years, ranging from 0-13 years, while, males (54.8%, N= 23) outnumbered females (45.2%, N=19). The TBSA burned interquartile range was 48%. In terms of etiology of burns Scald (73.8%, N=31) was the commonest cause of injury. Mortality risk factors identified were Age <6 years (P=0.028); Scald especially hot water and soup (P=0.016); TBSA >36% (P=0.028) and Inhalation injury (P=0.040). Conclusion: Age, scald, TBSA and Inhalation Injury were identified as pediatric burns mortality risk factors in a developing country such as Ghana’s RPSBU. These identified factors will serve as a guideline for plastic surgeons and other health professionals practicing in countries such as Ghana. PMID:23875121

  10. Genital burns in the national burn repository: incidence, etiology, and impact on morbidity and mortality.

    PubMed

    Harpole, Bethany G; Wibbenmeyer, Lucy A; Erickson, Bradley A

    2014-02-01

    To better characterize national genital burns (GBs) characteristics using a large burn registry. We hypothesized that mortality and morbidity will be higher in patients with GBs. The National Burn Repository, a large North American registry of hospitalized burn patients, was queried for patients with GB. Burn characteristics and mechanism, demographics, mortality, and surgical interventions were retrieved. Outcomes of interest were mortality, hospital-acquired infection (HAI), and surgical intervention on the genitalia. Adjusted odds ratios (aOR) for outcomes were determined with binomial logistic regression controlling for age, total burn surface area, race, length of stay, gender, and inhalation injury presence. GBs were present in 1245 cases of 71,895 burns (1.7%). Patients with GB had significantly greater average total burn surface area, length of stay, and mortality. In patients with GB, surgery of the genitalia was infrequent (10.4%), with the aOR of receiving surgery higher among men (aOR 2.7, P <.001) and those with third-degree burns (aOR 3.1, P <.002). Presence of a GB increased the odds of HAI (aOR 3.0, P <.0001) and urinary tract infections (aOR 3.4, P <.0001). GB was also an independent predictor of mortality (aOR 1.54) even after adjusting for the increased HAI risk. GBs are rare but associated with higher HAI rates and higher mortality after adjusting for well-established mortality risk factors. Although a cause and effect relationship cannot be established using these registry data, we believe this study suggests the need for special management considerations in GB cases to improve overall outcomes. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Diabetes mellitus and burns. Part II-outcomes from burn injuries and future directions

    PubMed Central

    Goutos, Ioannis; Nicholas, Rebecca Spenser; Pandya, Atisha A; Ghosh, Sudip J

    2015-01-01

    Diabetes mellitus is an increasingly prevalent comorbidity in patients presenting to burn facilities. Diabetic patients tend to be older and present in a delayed manner with deeper injuries predominantly affecting the lower limb. Morbidity from burns is higher in this cohort including a longer length of hospital stay, greater need for surgical interventions and increased rate of infective complications. Nevertheless, there seems to be little effect of diabetes on associated mortality. The second part of this review article concentrates on the epidemiological profile of diabetic burn patients and the effect of the disease on morbidity and mortality. In addition, we present a review of therapeutic adjuncts, which may hold promise for the future management of this cohort of burn patients. PMID:26064798

  12. Factors associated with mortality in adult hospitalized burn patients in Tehran.

    PubMed

    Zarei, Mohammad Reza; Dianat, Seyedsaied; Eslami, Vahid; Harirchi, Iraj; Boddouhi, Nosratollah; Zandieh, Ali; Rasouli, Mohammad R

    2011-01-01

    The mortality rate following burn is an important outcome parameter. This study aimed to identify factors associated with mortality in adult hospitalized burn patients in Tehran, Iran. This cross-sectional study was performed during a one-year period in two referral burn centers in Tehran. During the study period, 1321 adult (> 15 years) hospitalized burn patients were enrolled. Univariate and multivariate (logistic regression) analyses were performed to identify factors associated with mortality. The mean age of the patients was 33.1 ± 14.9 years. By far, the majority of burns were accidental (n = 1076, 81.5%). Regarding the mechanism of burn, burn with petroleum products was the most frequent. Mean percent burned total body surface area (TBSA) was 39.9% ± 25.8%. The mortality rate was 33%. Sepsis was the most common cause of mortality. The results of the present study indicated that non work-related burns, burned TBSA and body surface area affected by second- or third-degree burns were independent determinants of mortality among adult hospitalized burn patients. The present study showed a high mortality rate in the studied burn centers. Patients with identified risk factors should be categorized as high risk at the time of admission and need special attention and care during hospitalization.

  13. Catalyst patterning for nanowire devices

    NASA Technical Reports Server (NTRS)

    Li, Jun (Inventor); Cassell, Alan M. (Inventor); Han, Jie (Inventor)

    2004-01-01

    Nanowire devices may be provided that are based on carbon nanotubes or single-crystal semiconductor nanowires. The nanowire devices may be formed on a substrate. Catalyst sites may be formed on the substrate. The catalyst sites may be formed using lithography, thin metal layers that form individual catalyst sites when heated, collapsible porous catalyst-filled microscopic spheres, microscopic spheres that serve as masks for catalyst deposition, electrochemical deposition techniques, and catalyst inks. Nanowires may be grown from the catalyst sites.

  14. Tar burns in the southwest.

    PubMed

    Schiller, W R

    1983-07-01

    The burns which result from contact of human skin with hot tar may be quite serious in proportion to the body surface area involved. Although tending toward partial thickness burns, patchy areas of full thickness skin loss are commonly observed. The use of petrolatum-based ointments on the burn initially to dissolve the tar into the dressings seems like the most efficient and humane method of tar removal. Subsequently, care of the wound is like that of any other burn. Tar burns involving greater than 10 per cent of the body surface area are likely to be the most serious and require intravenous fluid resuscitation. Many tar burns appear to be preventable.

  15. Hydroliquefaction of coal with supported catalysts: 1980 status review

    SciTech Connect

    Polinski, Leon M.; Stiegel, Gary J.; Tischer, Richard E.

    1981-06-01

    The objectives of the program have been to determine catalyst deactivation kinetic models and catalyst deactivation modes for supported Co-Mo and Ni-Mo catalysts used primarily in coal liquefaction via the H-COAL process. Emphasis has been on developing methods to increase catalyst usage by determining how to decrease catalyst replacement rates in the process and how to decrease catalyst poisoning. An important conclusion reached via model analysis and verified by experiment is that larger diameter (1/16 in.) catalysts resist poisoning deactivation much more than smaller (1/32 in.) catalysts over extended periods (60 to 110 hours) of time. If this trend can be verified, it gives a powerful tool for reducing catalyst replacement rate in the H-COAL ebullated bed system by factors of 2 or more. A second conclusion is that poisoning of catalysts occurs by several possible mechanisms or modes. Indirect or direct evidence of all these modes can be presented, though the relative importance of each mechanism has not been established. The modes include (a) poisoning by coking - with gradual increase in C/H ratio (more refractory coke) with time, (b) poisoning by metallization (selective/non-selective adsorption of inorganics such as Ti and Fe on the catalyst), (c) sintering - increase in larger pores/decrease in surface area, and (d) parallel poisoning by irreversible nitrogen compound adsorption.

  16. Burning trees and bridges

    NASA Technical Reports Server (NTRS)

    Levine, Joel S.

    1990-01-01

    Most burning of biomass is the result of human activity, and on a global scale it is increasing. Tropospheric concentrations of CO2, CO, CH4, non-methane hydrocarbons, and ozone are all increasing with time; global biomass burning may make an important contribution to this increase and thus to potential global climate change. The nitrogen cycle also can have important climatic effects. Nitrous oxide put into the atmosphere by biomass burning is a greenhouse gas 250 times more powerful (molecule for molecule) than carbon dioxide. Nitric oxide, as well as being a photochemical precursor of ozone, a major pollutant in the troposphere, produces nitric acid, the fastest-growing component of acid rain. Hence, the new bridge in the nitrogen cycle is of more than mere technical interest.

  17. 'Special effects' burn injuries.

    PubMed

    Peters, W

    1991-02-01

    Three patients are presented with significant flame burns, resulting from accidents occurring during 'special effects' situations in the entertainment industry. These occurred as a result of the spontaneous combustion of various materials, during events in live theatre (gun powder), a television commercial (artificial 'rocket fuel'), and a video presentation (magnesium oxide). All three patients sustained flash burns to the face and hands. One patient sustained a significant bilateral corneal injury, a gamekeeper's thumb, and a permanent continuous right-sided high frequency tinnitus, in addition to his burn injury. Photographic documentation of all three patients is presented. The total loss of time from work for all patients was 6 months. All these injuries were potentially preventable.

  18. Epidemiology of burns in Lithuania during 1991-2004.

    PubMed

    Rimdeika, Rytis; Kazanavicius, Mindaugas; Kubilius, Darius

    2008-01-01

    The objective of this article is to overview and present the burn incidence and burn care in Lithuania. In this study, data from the period of 1991-2004 were collected from the Lithuanian Department of Statistics, Department of Fire and Rescue, Lithuanian Health Information Center, State Patient Fund, health care institutions, burn care facilities. In the 14-year period, 9459 persons per year (2.6/1000 population) in average sustained burn injuries. The majority of burned patients (74.8%) were adults and 25.2% were children; 21.5% of all burned patients were hospitalized (2013 inpatients per year). The number of hospitalizations per 100 000 individuals has decreased from 65.6 to 39.5, but it is still very high and worrying. Among all the patients admitted to hospitals, 67% were males and 33% females, with a male-to-female ratio of 2:1. The length of hospitalization decreased from 16.2 to 12.7 days. The number of fire-related deaths for the 14-year period was 289 deaths per year (8 per 100 000 persons). The number of deaths among inpatients was 63.6 deaths per year, the age being an important factor in mortality rates. Although the mortality of inpatients has increased in recent years, the mortality in the age group up to 14 years has decreased to 0. Children made up 24.6% of burn patients; among those admitted to hospital, they accounted for 41.1%. Mortality rates for males and females were almost the same. The number of burns is decreasing. The hospitalization rate and hospitalization time are becoming shorter. In the last few years, patients suffer from more severe burns, while children sustain more severe burns requiring hospitalization. Children and working-age persons make up 91.9% of hospitalized burn patients. Number of deaths in fire accidents is increasing.

  19. Burn Safety Awareness on Playgrounds: Thermal Burns from Playground Equipment

    MedlinePlus

    ... Safety Awareness on Playgrounds Thermal Burns from Playground Equipment The U.S. Consumer Product Safety Commission CPSC wants ... of the risk of thermal burns from playground equipment. You may remember the metal slides of your ...

  20. Epidemiology and outcome of burns at the Saud Al Babtain Burns, Plastic Surgery and Reconstructive Center, Kuwait: our experience over five years (from 2006 to 2010).

    PubMed

    Khashaba, H A; Al-Fadhli, A N; Al-Tarrah, K S; Wilson, Y T; Moiemen, N

    2012-12-31

    Aim To determine the epidemiology and clinical presentation, and any contributing factors responsible for burns and outcome of care in Kuwait over the 5-yr period January 2006 to December 2010. Patients and methods. The study reviewed 1702 burn patients admitted over the study period to the Saud Al Babtain Burns, Plastic and Reconstructive Surgery Center, Kuwait. Patient characteristics, including age, sex, type of burn, nationality, total body surface area (TBSA) burn, hospital stay in days, and mortality were recorded. Results. Seventy-one per cent of the 1702 burn patients admitted were males; 540 were children. The majority of patients (64%) had less than 15% TBSA burns and only 14% had more than 50% TBSA burns. Flame burns were the most common cause of burn injuries (60%), followed by scalds (29%). Scalds were most common in children. The mortality rate was 5.75%. Flame burn was the leading cause of mortality. Lethal dose 50 (% TBSA at which a certain group has a 50% chance of survival) for adults (16-40 yr) and for the elderly (>65 yr) was 76.5% and 41.8% TBSA respectively. Conclusion. Burn injury is an important public health concern and is associated with high morbidity and mortality. Flame and scald burns are commonly a result of domestic and occupational accidents and they are preventable. Effective initial resuscitation, infection control, and adequate surgical treatment improve outcomes.

  1. Epidemiology and outcome of burns at the Saud Al Babtain Burns, Plastic Surgery and Reconstructive Center, Kuwait: our experience over five years (from 2006 to 2010)

    PubMed Central

    Khashaba, H.A.; Al-Fadhli, A.N.; Al-Tarrah, K.S.; Wilson, Y.T.; Moiemen, N.

    2012-01-01

    Summary Aim To determine the epidemiology and clinical presentation, and any contributing factors responsible for burns and outcome of care in Kuwait over the 5-yr period January 2006 to December 2010. Patients and methods. The study reviewed 1702 burn patients admitted over the study period to the Saud Al Babtain Burns, Plastic and Reconstructive Surgery Center, Kuwait. Patient characteristics, including age, sex, type of burn, nationality, total body surface area (TBSA) burn, hospital stay in days, and mortality were recorded. Results. Seventy-one per cent of the 1702 burn patients admitted were males; 540 were children. The majority of patients (64%) had less than 15% TBSA burns and only 14% had more than 50% TBSA burns. Flame burns were the most common cause of burn injuries (60%), followed by scalds (29%). Scalds were most common in children. The mortality rate was 5.75%. Flame burn was the leading cause of mortality. Lethal dose 50 (% TBSA at which a certain group has a 50% chance of survival) for adults (16-40 yr) and for the elderly (>65 yr) was 76.5% and 41.8% TBSA respectively. Conclusion. Burn injury is an important public health concern and is associated with high morbidity and mortality. Flame and scald burns are commonly a result of domestic and occupational accidents and they are preventable. Effective initial resuscitation, infection control, and adequate surgical treatment improve outcomes. PMID:23766750

  2. Rocket plume burn hazard.

    PubMed

    Stoll, A M; Piergallini, J R; Chianta, M A

    1980-05-01

    By use of miniature rocket engines, the burn hazard posed by exposure to ejection seat rocket plume flames was determined in the anaesthetized rat. A reference chart is provided for predicting equivalent effects in human skin based on extrapolation of earlier direct measurements of heat input for rat and human burns. The chart is intended to be used in conjunction with thermocouple temperature measurements of the plume environment for design and modification of escape seat system to avoid thermal injury on ejection from multiplace aircraft.

  3. Burning mouth syndrome

    PubMed Central

    Jimson, Sudha; Rajesh, E.; Krupaa, R. Jayasri; Kasthuri, M.

    2015-01-01

    Burning mouth syndrome (BMS) is a complex disorder that is characterized by warm or burning sensation in the oral mucosa without changes on physical examination. It occurs more commonly in middle-aged and elderly women and often affects the tip of the tongue, lateral borders, lips, hard and soft palate. This condition is probably of multi-factorial origin, often idiopathic, and its etiopathogensis is unknown. BMS can be classified into two clinical forms namely primary and secondary BMS. As a result, a multidisciplinary approach is required for better control of the symptoms. In addition, psychotherapy and behavioral feedback may also help eliminate the BMS symptoms. PMID:26015707

  4. Burning mouth syndrome.

    PubMed

    Torgerson, Rochelle R

    2010-01-01

    Burning mouth syndrome (BMS) is a chronic condition characterized by burning of the oral mucosa, with or without dysgeusia and xerostomia, in the setting of no underlying systemic disease or identifiable abnormalities on physical examination or laboratory testing. BMS disproportionately affects postmenopausal women. The pathophysiology of the disease is unknown; no single treatment has proven universally successful. In light of these shortcomings, having a practical approach to the evaluation and management of patients with BMS can improve both patient quality of life and physician satisfaction.

  5. Textured catalysts and methods of making textured catalysts

    DOEpatents

    Werpy, Todd; Frye, Jr., John G.; Wang, Yong; Zacher, Alan H.

    2007-03-06

    A textured catalyst having a hydrothermally-stable support, a metal oxide and a catalyst component is described. Methods of conducting aqueous phase reactions that are catalyzed by a textured catalyst are also described. The invention also provides methods of making textured catalysts and methods of making chemical products using a textured catalyst.

  6. Methamphetamine-related burns in the cornbelt.

    PubMed

    Burke, Bridget A; Lewis, Robert W; Latenser, Barbara A; Chung, Joseph Y; Willoughby, Clark; Kealey, G Patrick; Wibbenmeyer, Lucy A

    2008-01-01

    Methamphetamine (MA) is a highly addictive drug that is easily manufactured from everyday household products and chemicals found at local farm stores. The proliferation of small MA labs has led to a dramatic increase in patients sustaining thermal injury while making and/or using MA. We hypothesized that these patients have larger injuries with longer hospital stays, and larger, nonreimbursed hospital bills compared with burn patients not manufacturing or using MA. In a retrospective case-control study, all burn patients >or=16 years of age admitted to our burn center from January 2002 to December 2005 were stratified into two groups based on urine MA status. Of the 660 burn patients >or=16 years of age admitted during this 4 year period, urine drug screens were obtained at admission on 410 patients (62%); 10% of urine drug screens were MA (+). MA (+) patients have larger burns compared with MA (-) patients (9.3 vs 8.6% body surface area burns), have higher rates of inhalation injuries (20.4 vs 9.3%, P = .015), and more nonthermal trauma (13.0 vs 3.1%, P = .001). When compared with MA (-) patients, MA (+) patients require longer hospital stays (median 9.5 vs 7.0 days, P = .036), accrue greater hospital bills per day (dollars 4292 vs dollars 2797, P = .01), and lack medical insurance (66.7 vs 17.7%, P < .0001). The epidemic of MA use and its manufacture mandates that burn centers monitor patients for MA use and develop and institute protocols to ensure proper care of this increasingly costly population.

  7. CHARACTERIZATION OF EMISSIONS FROM BURNING INCENSE

    EPA Science Inventory

    The primary objective of this study was to improve the characterization of particulate matter emissions from burning incense. Emissions of particulate matter were measured for 23 different types of incense using a cyclone/filter method. Emission rates for PM2.5 (particulate matte...

  8. CHARACTERIZATION OF EMISSIONS FROM BURNING INCENSE

    EPA Science Inventory

    The primary objective of this study was to improve the characterization of particulate matter emissions from burning incense. Emissions of particulate matter were measured for 23 different types of incense using a cyclone/filter method. Emission rates for PM2.5 (particulate matte...

  9. Biomass Burning Observation Project Science Plan

    SciTech Connect

    Kleinman, KI; Sedlacek, AJ

    2013-09-01

    Aerosols from biomass burning perturb Earth’s climate through the direct radiative effect (both scattering and absorption) and through influences on cloud formation and precipitation and the semi-direct effect. Despite much effort, quantities important to determining radiative forcing such as the mass absorption coefficients (MAC) of light-absorbing carbon, secondary organic aerosol (SOA) formation rates, and cloud condensation nuclei (CCN) activity remain in doubt. Field campaigns in northern temperate latitudes have been overwhelmingly devoted to other aerosol sources in spite of biomass burning producing about one-third of the fine particles (PM2.5) in the U.S.

  10. Burn injury secondary to air bag deployment.

    PubMed

    Hendrickx, Ingrid; Mancini, Luca Livio; Guizzardi, Marco; Monti, Marcello

    2002-02-01

    The efficacy of air bags has been proven in diminishing the rate of fatalities and severity of injury in motor vehicle crashes. Unfortunately, as with any developing technology, new problems have been encountered that are directly attributable to the deployment of the air bag itself. Most air bag-related injuries are minor and, surprisingly, more than 7% are burns typically involving the upper extremity or head or neck. Fortunately, these are superficial burns that usually require only expectant therapy, but a high degree of suspicion in these circumstances is needed to make the proper diagnosis.

  11. Suitable combination of promoter and micellar catalyst for kilo fold rate acceleration on benzaldehyde to benzoic acid conversion in aqueous media at room temperature: a kinetic approach.

    PubMed

    Ghosh, Aniruddha; Saha, Rumpa; Ghosh, Sumanta K; Mukherjee, Kakali; Saha, Bidyut

    2013-05-15

    The kinetics of oxidation of benzaldehyde by chromic acid in aqueous and aqueous surfactant (sodium dodecyl sulfate, SDS, alkyl phenyl polyethylene glycol, Triton X-100 and N-cetylpyridinium chloride, CPC) media have been investigated in the presence of promoter at 303 K. The pseudo-first-order rate constants (kobs) were determined from a logarithmic plot of absorbance as a function time. The rate constants were found to increase with introduction of heteroaromatic nitrogen base promoters such as Picolinic acid (PA), 2,2'-bipyridine (bipy) and 1,10-phenanthroline (phen). The product benzoic acid has been characterized by conventional melting point experiment, NMR, HRMS and FTIR spectral analysis. The mechanism of both unpromoted and promoted reaction path has been proposed for the reaction. In presence of the anionic surfactant SDS, cationic surfactant CPC and neutral surfactant TX-100 the reaction can undergo simultaneously in both aqueous and micellar phase with an enhanced rate of oxidation in the micellar phase. Both SDS and TX-100 produce normal micellar effect whereas CPC produce reverse micellar effect in the presence of benzaldehyde. The observed net enhancement of rate effects has been explained by considering the hydrophobic and electrostatic interaction between the surfactants and reactants. SDS and bipy combination is the suitable one for benzaldehyde oxidation. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. [Analysis of burn treatment for children at Bochum University Hospital].

    PubMed

    Langer, S; Hilburg, M; Drücke, D; Herweg-Becker, A; Steinsträsser, L; Steinau, H U

    2006-10-01

    A retrospective epidemiological multifactorial study of pediatric burn patients admitted to the Burn Center Bochum in the period of 1992-2002 was performed. Data from 628 patients were analyzed and included age, sex, mortality, hospital stay, percent of total body surface area (TBSA) burned, localization of burns, number of surgical procedures, source of the burn as well as social standing of the families. The majority of patients (414) were between 0 and 3 years. The median age was 2.99. The median TBSA was 11.9%. There were 387 males (62%) and 241 females (38%, ratio of 1.6:1). The overall mortality rate was 1.4% (6/629). The main causes of injury were scald burns (435; 70%), followed by flame burns (153; 24%), electric injuries (17; 3%), and hot oil (21; 3%). Surgery was performed on 365 (58%) children. The others (263; 42%) were treated without surgery. The number of children with a background other than German was higher; moreover, a high number of injuries was not covered by health insurance. Having identified the high-risk group among the pediatric burn patients, we suggest that prevention programs should be directed towards these families in order to reduce further risk of pediatric burns.

  13. In view of standardization: comparison and analysis of initial management of severely burned patients in Germany, Austria and Switzerland.

    PubMed

    Münzberg, Matthias; Ziegler, Benjamin; Fischer, Sebastian; Wölfl, Christoph Georg; Grützner, Paul Alfred; Kremer, Thomas; Kneser, Ulrich; Hirche, Christoph

    2015-02-01

    Initial treatment of severely injured patients in German speaking trauma centers follows precise sequences. Several guidelines and training courses ensure a constant quality in providing evidence-based treatment for these patients. Similar standards, algorithms and guidelines for the treatment of severely burned patients are lacking. This raises the question about the current standard of care for burn victims in German speaking burn centers. In order to achieve standardization, as a first step this study surveys principles of burn room organization and management in these burn centers. A questionnaire including 40 questions regarding burn room organization, personnel structure and qualification, infrastructural conditions and quality management was developed and sent to 21 level one burn centers in Germany, Austria and Switzerland. The rate of returned questionnaires was 81%. The analysis revealed varying personnel and infrastructural conditions in participating burn centers. Indications for admission to the burn room and admission procedures itself are different throughout surveyed hospitals. Individual standard operating procedure (SOP) for burn trauma admissions was available in most burn centers and nearly all participants register their burn trauma cases using an in-house burn register. The survey suggests a lack of standardization in personnel structure, infrastructure and treatment approach for the initial clinical care of severely burned patients in burn centers across the German speaking countries. Further evaluation of existing protocols and international standards in burn care is inevitable to develop standardized guidelines for burn care and to improve quality of care. Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.

  14. Burns in Turkish children and adolescents: nine years of experience.

    PubMed

    Sakallioğlu, A E; Başaran, O; Tarim, A; Türk, E; Kut, A; Haberal, M

    2007-02-01

    The aim of this study was to describe information about burns that occur in children and adolescents in Turkey. The subjects were 362 patients whom were younger than 18 years who were treated at 3 burn centers in 2 different regions of Turkey between 1997 and 2005. The data collected for each case were age, gender, place of residence, cause and extent of burn, body sites affected, environment in which the injury occurred, interval from injury to arrival at a burn center, hospitalization status (inpatient versus outpatient), surgical treatment, and mortality. The 362 patients comprised 35.5% of all 1021 burn victims admitted during the study period. There were 183 boys and 179 girls (ratio 1:0.98) and the mean total body surface area burned was 17.7+/-16.5%. The highest proportion of patients were in the 1-6 years age group. Non-bath (not immersed) hot water scalding (216 cases, 59.7%) was the leading burn cause. The most common environment in which burn injury occurred was the home. The trunk was the body site most frequently affected (62.7%). 241 (66.6%) subjects lived in urban environments and 121 (33.4%) lived in rural areas. 171 patients (47.2%) were taken directly to the burn units, whereas the others (52.8%) were referred from other medical centers. 124 (34.3%) subjects were treated as outpatients and 238 (65.7%) were hospitalized. The overall mortality rate was 8.6% (31 deaths). Of the 238 inpatients, 92 (38.7%) were treated with daily dressings only, 128 (53.8%) required debridement, and 75 (31.5%) needed both debridement and grafting. Every country needs a nationwide public education system that is aimed at preventing burns and ensuring that burn victims receive proper first aid and age-appropriate, specialized burn care.

  15. Association Between Burn Injury and Mental Illness among Burn Survivors: A Population-Based, Self-Matched, Longitudinal Cohort Study.

    PubMed

    Mason, Stephanie A; Nathens, Avery B; Byrne, James P; Ellis, Janet; Fowler, Robert A; Gonzalez, Alejandro; Karanicolas, Paul J; Moineddin, Rahim; Jeschke, Marc G

    2017-10-01

    Mental health disorders are prevalent before and after burn injury. However, the impact of burn injury on risk of subsequent mental health disorders is unknown. We conducted a population-based, self-matched longitudinal cohort study using administrative data in Ontario, Canada between 2003 and 2011. All adults who survived to discharge after major burn injury were included, and all mental health-related emergency department visits were identified. Rate ratios (RRs) for mental health visits in the 3 years after burn, compared with the 3 years before, were estimated using negative binomial generalized estimating equations. Among 1,530 patients with major burn injury, mental health visits were common both before (141 per 1,000 person years) and after (154 per 1,000 person years) injury. Mental health visits were most common in the 12 weeks immediately preceding injury. No significant difference in the overall visit rate was observed after burn (RR 0.97; 95% CI 0.78 to 1.20), although among patients with less than 1 pre-injury visit, mental health visits tripled (RR 3.72; 95% CI 2.70 to 5.14). Self-harm emergencies increased 2-fold (RR 1.95; 95% CI 1.15 to 3.33). Mental health emergencies are prevalent among burn-injured patients. Although the overall rate of mental health visits is not increased after burn, the rate increases significantly among patients with one or fewer visits pre-injury. Self-harm risk increases significantly after burn injury, underscoring the need for screening and targeted interventions after discharge. An increased rate immediately before burn suggests an opportunity for injury prevention through mental healthcare. Copyright © 2017 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

  16. Epidemiology of burns in Taiwan: a nationwide report including inpatients and outpatients.

    PubMed

    Chen, Shih-Han; Chen, Yi-Chun; Chen, Tzeng-Ji; Ma, Hsu

    2014-11-01

    The aim of the study is to understand the incidence of burns among outpatients and inpatients of Taiwan in 2010. Characteristics of the burned patients were also studied in terms of gender, age, burn sites, burn degree, reconstructive surgical treatment, as well as which specialty and medical facility they are treated in. Burned patients were identified from the 1,000,000-person cohort dataset sampled from the Taiwan National Health Insurance database. Ones who had been hospitalized with discharge diagnoses related to burns were categorized as inpatients and others who had only ambulatory visits and emergency room visits were classified as outpatients. 7630 burn-injury patients were found, presenting an annual incidence of burns as 670.8/10(5) in males (n=3303) and 852.5/10(5) in females (n=4327). Only 3.4% (156 males and 107 females) of them were hospitalized. Higher incidence of burns were found in females and young children, while males and the elderly tended to have more severe burns, based on high-degree burns, admission rate, and incidence of hospitalizations for burns. This is a population-based study demonstrating the epidemiology of burns among outpatients and inpatients in Taiwan, leading us closer to the reality of burns treated in different settings of medical facilities. Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.

  17. Phoenix Society for Burn Survivors

    MedlinePlus

    ... Community Blog Taking Care of Yourself at Phoenix World Burn Congress 3 Oct 2017 Imagine this: a ... Menu Get Support Find Resources Our Programs Phoenix World Burn Congress Get Involved Ways to Give Who ...

  18. [Burns in an aeronautic environment].

    PubMed

    Rigotti, G

    1979-10-27

    Following an examination of the aetiology of burns in aeronautic environments, the physiopathology, classification and general and local treatment of the burn case is discussed. Special mention is then made of aircraft as an extremely useful means of transport.

  19. Discovery Performs Terminal Initiation Burn

    NASA Image and Video Library

    The terminal initiation burn, a left Orbital Maneuvering System engine firing that gave Discovery one last big push toward the space station, took place Feb. 26, 2011 at 10:33 a.m. The burn lasted ...

  20. In Situ Burning of Oil Spills

    PubMed Central

    Evans, David D.; Mulholland, George W.; Baum, Howard R.; Walton, William D.; McGrattan, Kevin B.

    2001-01-01

    For more than a decade NIST conducted research to understand, measure and predict the important features of burning oil on water. Results of that research have been included in nationally recognized guidelines for approval of intentional burning. NIST measurements and predictions have played a major role in establishing in situ burning as a primary oil spill response method. Data are given for pool fire burning rates, smoke yield, smoke particulate size distribution, smoke aging, and polycyclic aromatic hydrocarbon content of the smoke for crude and fuel oil fires with effective diameters up to 17.2 m. New user-friendly software, ALOFT, was developed to quantify the large-scale features and trajectory of wind blown smoke plumes in the atmosphere and estimate the ground level smoke particulate concentrations. Predictions using the model were tested successfully against data from large-scale tests. ALOFT software is being used by oil spill response teams to help assess the potential impact of intentional burning. PMID:27500022

  1. Ventilator associated pneumonia in major paediatric burns.

    PubMed

    Rogers, Alan David; Deal, Cailin; Argent, Andrew Charles; Hudson, Donald Anthony; Rode, Heinz

    2014-09-01

    More than three-quarters of deaths related to major burns are a consequence of infection, which is frequently ventilator associated pneumonia (VAP). A retrospective study was performed, over a five-year period, of ventilated children with major burns. 92 patients were included in the study; their mean age was 3.5 years and their mean total body surface area burn was 30%. 62% of the patients sustained flame burns, and 31% scalds. The mean ICU stay was 10.6 days (range 2-61 days) and the mean ventilation time was 8.4 days (range 2-45 days). There were 59 documented episodes of pneumonia in 52 patients with a rate of 30 infections per 1000 ventilator days. Length of ventilation and the presence of inhalational injury correlate with the incidence of VAP. 17.4% of the patients died (n=16); half of these deaths may be attributed directly to pneumonia. Streptococcus pneumonia, Pseudomonas aeruginosa, Acinetobacter baumanii and Staphylococcus aureus were the most prominent aetiological organisms. Broncho-alveolar lavage was found to be more specific and sensitive at identifying the organism than other methods. This study highlights the importance of implementing strictly enforced strategies for the prevention, detection and management of pneumonia in the presence of major burns.

  2. Methods of making textured catalysts

    DOEpatents

    Werpy, Todd [West Richland, WA; Frye, Jr., John G.; Wang, Yong [Richland, WA; Zacher, Alan H [Kennewick, WA

    2010-08-17

    A textured catalyst having a hydrothermally-stable support, a metal oxide and a catalyst component is described. Methods of conducting aqueous phase reactions that are catalyzed by a textured catalyst are also described. The invention also provides methods of making textured catalysts and methods of making chemical products using a textured catalyst.

  3. Catalyst Alloys Processing

    NASA Astrophysics Data System (ADS)

    Tan, Xincai

    2014-10-01

    Catalysts are one of the key materials used for diamond formation at high pressures. Several such catalyst products have been developed and applied in China and around the world. The catalyst alloy most widely used in China is Ni70Mn25Co5 developed at Changsha Research Institute of Mining and Metallurgy. In this article, detailed techniques for manufacturing such a typical catalyst alloy will be reviewed. The characteristics of the alloy will be described. Detailed processing of the alloy will be presented, including remelting and casting, hot rolling, annealing, surface treatment, cold rolling, blanking, finishing, packaging, and waste treatment. An example use of the catalyst alloy will also be given. Industrial experience shows that for the catalyst alloy products, a vacuum induction remelt furnace can be used for remelting, a metal mold can be used for casting, hot and cold rolling can be used for forming, and acid pickling can be used for metal surface cleaning.

  4. Burn Wise Outreach Materials for Retailers

    EPA Pesticide Factsheets

    Burn Wise outreach material. Burn Wise is a partnership program of that emphasizes the importance of burning the right wood, the right way, in the right wood-burning appliance to protect your home, health, and the air we breathe.

  5. Burn Wise Educational Materials for Businesses

    EPA Pesticide Factsheets

    Burn Wise outreach material. Burn Wise is a partnership program of that emphasizes the importance of burning the right wood, the right way, in the right wood-burning appliance to protect your home, health, and the air we breathe.

  6. American Burn Association Consensus Statements

    DTIC Science & Technology

    2013-08-01

    Johnson DW, Pruitt BA Jr. Ef- fect of ambient temperature on heat production and heat loss in burn patients. J Appl Physiol 1975;38:593–7. 13. Dvir...R, Parker RS, Rodriguez JL. Carotenoids and antioxidant vitamins in patients after burn injury. J Burn Care Rehabil 1997;18:269–78; discus- sion...In response, review by the FDA of novel therapies has led to Guidance for Industry: chronic cutaneous ulcer and burn wounds—developing products

  7. Treating and Preventing Burns

    MedlinePlus

    ... so you can make certain everyone has gotten out of the burning area. Teach your children to stop, drop, and roll on the ground if their clothing catches fire. Avoid smoking​ indoors . Do not leave food ... home. It is best to store them outside the home, out of children's reach, and away from heat or ...

  8. The Earth Could Burn.

    ERIC Educational Resources Information Center

    Yarrow, Ruth

    1982-01-01

    Environmental educators are worried about the ultimate ecological threat--nuclear war, which could burn thousands of square miles, sterilize the soil, destroy 70 percent of the ozone layer letting in lethal ultraviolet rays, and cause severe radiation sickness. Educators must inform themselves, teach others, contact government representatives, and…

  9. The Earth Could Burn.

    ERIC Educational Resources Information Center

    Yarrow, Ruth

    1982-01-01

    Environmental educators are worried about the ultimate ecological threat--nuclear war, which could burn thousands of square miles, sterilize the soil, destroy 70 percent of the ozone layer letting in lethal ultraviolet rays, and cause severe radiation sickness. Educators must inform themselves, teach others, contact government representatives, and…

  10. Fungal Burn Wound Infection

    DTIC Science & Technology

    1991-01-01

    severely limits the may prove to be useful in burn patients. Clotrimazole , applied clinical utility of such a culture. Biopsy and frozen-section and as...useful in wound and permit prompt institution of appropriate the treatment of systemic fungal infections. Clotrimazole is treatment. poorly absorbed

  11. TIRES, OPEN BURNING

    EPA Science Inventory

    The chapter describes available information on the health effects from open burning of rubber tires. It concentrates on the three known sources of detailed measurements: (1) a small-scale emissions characterization study performed by the U.S. EPA in a facility designed to simulat...

  12. Chemical burn or reaction

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/000059.htm Chemical burn or reaction To use the sharing features on this page, please enable JavaScript. Chemicals that touch skin can lead to a reaction on the skin, throughout the body, or both. ...

  13. Burn and Scald Prevention

    MedlinePlus

    ... dry oven mitts or potholders. Hot cookware can heat moisture in a potholder or hot pad, resulting in a scald burn. • Wear short, close-fitting or tightly rolled sleeves when cooking. • Have a “kid-free zone” of at least 3 feet around the stove. ...

  14. Burn Care in Iraq

    DTIC Science & Technology

    2007-01-01

    tent configuration and later occupied Ibn Sina Hospital, in the international zone in Baghdad, Iraq. In the tent configura- tion, the 28th CSH provided...at Ibn Sina Hos- pital continuously. In a relatively austere general hospital environment, burn care has been provided with a focus on the

  15. TIRES, OPEN BURNING

    EPA Science Inventory

    The chapter describes available information on the health effects from open burning of rubber tires. It concentrates on the three known sources of detailed measurements: (1) a small-scale emissions characterization study performed by the U.S. EPA in a facility designed to simulat...

  16. [Burns with lighter gas].

    PubMed

    Davidsen, M T

    1993-06-28

    Attention is drawn to a particularly dangerous party activity. Balloons filled with lighter gas so as to float are used for party decorations. A case of hand burn caused by accidentally lighting such a balloon with a cigarette is reported. The method is strongly advised against, it is a much better idea to use helium for such purposes.

  17. [Burns in adolescents].

    PubMed

    Ortiz Rodríguez, R; Domínguez Amillo, E; Soto Beauregard, C; Díaz González, M; López Gutiérrez, J C; Ros Mar, Z; Tovar Larrucea, J A

    2012-04-01

    The aim of this study was to know the epidemiology of burns in teenagers. Burn patients over 11 years old admitted in our Institution in the last 10 years were included. Etiology, burn size, hospital stay, quirurgical interventions and long term sequelae were registered. One thousand and eight patients were admitted, 89 were over 11 years (8.8%), 70.7% were boys and 29.3% girls. Fire was the principal agent in 58 cases (65.1%), due to fireworks in 13 (22.4%), alcohol in 7 (12%), explosion of flammable containers (spray) in 4 (6.8%) and gasoline in 3 (5.2%). Fireworks injuries and spray explosions affected face and hand in 88% cases. The median hospital stay was 8 days after admission (1 to 90). 83.1% required surgical treatment with mean of 1.8 +/- 1.4 interventions and 21.3% had long-term sequelaes that required at least one surgical intervention. Fire is the main cause of burns in adolescents. Fireworks injuries represented a quarter of that lesions, and highlights paint spray explosions as new causative agents. Considering the high morbidity in this age group, with permanent functional and aesthetic sequelae, prevention campaigns are needed to reduce such accidents.

  18. Burning Your Own CDs.

    ERIC Educational Resources Information Center

    Ekhaml, Leticia

    2001-01-01

    Discusses the use of CDs (Compact Disks) for backing up data as an alternative to using floppy disks and explains how to burn, or record, a CD. Topics include differences between CD-R (CD-Recordable) and CD-RW (CD-Rewritable); advantages of CD-R and CD-RW; selecting a CD burner; technology trends; and care of CDs. (LRW)

  19. 40 CFR 49.10411 - Permits for general open burning, agricultural burning, and forestry and silvicultural burning.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., agricultural burning, and forestry and silvicultural burning. 49.10411 Section 49.10411 Protection of... for general open burning, agricultural burning, and forestry and silvicultural burning. (a) Beginning... obtain approval of a permit under § 49.134 Rule for forestry and silvicultural burning permits. ...

  20. The FLUORINE-17(PROTON, PHOTON)NEON-18 and Oxygen -14(ALPHA Particle, PROTON)FLUORINE-17 Reaction Rates and the Structure of NEON-18 (NEON-18, FLUORINE-17, Oxygen -14, Astrophysical Hydrogen Burning)

    NASA Astrophysics Data System (ADS)

    Hahn, Kevin Insik

    1993-01-01

    The 14O(alpha,p) 17F and ^ {17}F(p,gamma)18Ne reactions play crucial roles in the advanced stages of astrophysical hydrogen burning. The ^{14 }O(alpha,p)^ {17}F(p,gamma) ^ {18}Ne(beta^+nu) 18F(p,alpha)^ {15}O reaction sequence can provide a path around the relatively slow positron decay of 14O in the HCNO cycle, while the similar reaction sequence, ^{14 }O(alpha ,p) 17F(p,gamma)^ {18}Ne(beta ^+nu) 18F(p,gamma)^ {19}Ne, can provide an alternate path from the HCNO cycle to the rp-process. The 17F(p,gamma)18Ne reaction rate could provide the principal source of 18O. Under some astrophysical conditions, the ^{14 }O(alpha,p)^ {17}F reaction is expected to compete with the 15O(alpha, gamma)19Ne reaction in providing a path through which nuclei involved in the HCNO cycle can be transformed into heavier nuclei with Z >= 10.. In order to better determine the rates of these two reactions, we measured the properties of the resonances in 18Ne; the excitation energies, the spins, and the partial and total widths of the relevant resonances. By comparing the previously observed states in 18Ne to the well-studied isospin mirror nucleus, ^{18 }O, it is clear that there are a number of missing levels in 18Ne in the region rm Ex > 4 MeV. These missing states in ^ {18}Ne could be important in determining the 17F(p, gamma)18rm Ne and 14O(alpha ,p)17F reaction rates. We have studied the ^{12 }C(12C,^6He)^{18 }Ne, 20rm Ne(p{,}t)18Ne, and 16O(^3He{, }n)18Ne reactions to measure new nuclear structure information of ^{18 }Ne. From our experiments, we have the following major results: (a) an evidence of the 3^+ <=vel at E_{rm x} = 4.56 MeV, (b) new levels at E_ {rm x} = 6.15 MeV, 7.12 MeV, 7.35 MeV, 7.62 MeV, 8.30 MeV, (8.45 MeV), 8.55 MeV, 8.94 MeV, and 9.58 MeV. (c) new J^pi assignments to the 5.11/5.15-MeV doublet and the 6.15-MeV state. Our discovery of the 3^+<=vel at an energy ~230 keV higher than calculated by Wiescher, Gorres, and Thielemann causes the contribution of the 17 F

  1. Hypocupremia in a major burn.

    PubMed

    Brian, J E; Caldwell, F T; Woody, R C; Bowser-Wallace, B H

    1987-03-01

    Trace element deficiency in burns is an area which apparently has not been investigated. We recently encountered a severely burned patient with profound copper depletion. Neuropsychiatric symptoms and delayed healing may have been secondary to this deficiency. Further study is needed to clearly delineate the role of acquired copper deficiency in recovering burned patients.

  2. The overall patterns of burns

    PubMed Central

    Almoghrabi, A.; Abu Shaban, N.

    2011-01-01

    Summary Burn patterns differ across the whole world and not only in relation to lack of education, overcrowding, and poverty. Cultures, habits, traditions, psychiatric illness, and epilepsy are strongly correlated to burn patterns. However, burns may also occur because of specific religious beliefs and activities, social events and festivals, traditional medical practices, occupational activities, and war. PMID:22639565

  3. Repeated Prescribed Burning in Aspen

    Treesearch

    Donald A. Perala

    1974-01-01

    Infrequent burning weather, low flammability of the aspen-hardwood association, and prolific sprouting and seeding of shrubs and hardwoods made repeated dormant season burning a poor tool to convert good site aspen to conifers. Repeat fall burns for wildlife habitat maintenance is workable if species composition changes are not important.

  4. METHOD OF PURIFYING CATALYSTS

    DOEpatents

    Joris, G.G.

    1958-09-01

    It has been fuund that the presence of chlorine as an impurity adversely affects the performance of finely divided platinum catalysts such as are used in the isotopic exchange process for the production of beavy water. This chlorine impurity may be removed from these catalysts by treating the catalyst at an elevated temperature with dry hydrogen and then with wet hydrogen, having a hydrogen-water vapor volume of about 8: 1. This alternate treatment by dry hydrogen and wet hydrogen is continued until the chlorine is largely removed from the catalyst.

  5. Polyolefin catalyst manufacturing

    SciTech Connect

    Inkrott, K.E.; Scinta, J.; Smith, P.D. )

    1989-10-16

    Statistical process control (SPC) procedures are absolutely essential for making new-generation polyolefin catalysts with the consistent high quality required by modern polyolefin processes. Stringent quality assurance is critical to the production of today's high-performance catalysts. Research and development efforts during the last 20 years have led to major technological improvements in the polyolefin industry. New generation catalysts, which once were laboratory curiosities, must now be produced commercially on a regular and consistent basis to meet the increasing requirements of the plastics manufacturing industry. To illustrate the more stringent requirements for producing the new generation polyolefin catalysts, the authors compare the relatively simple, first-generation polypropylene catalyst production requirements with some of the basic requirements of manufacturing a more complex new-generation catalyst, such as Catalyst Resources Inc.'s LYNX 900. The principles which hold true for the new-generation catalysts such as LYNX 900 are shown to apply equally to the scale-up of other advanced technology polyolefin catalysts.

  6. Liquefaction with microencapsulated catalysts

    DOEpatents

    Weller, Sol W.

    1985-01-01

    A method of dispersing a liquefaction catalyst within coal or other carbonaceous solids involves providing a suspension in oil of microcapsules containing the catalyst. An aqueous solution of a catalytic metal salt is emulsified in the water-immiscible oil and the resulting minute droplets microencapsulated in polymeric shells by interfacial polycondensation. The catalyst is subsequently blended and dispersed throughout the powdered carbonaceous material to be liquefied. At liquefaction temperatures the polymeric microcapsules are destroyed and the catalyst converted to minute crystallites in intimate contact with the carbonaceous material.

  7. Burning Mouth Syndrome: update.

    PubMed

    Spanemberg, Juliana Cassol; Rodríguez de Rivera Campillo, Eugenia; Salas, Enric Jané; López López, José

    2014-06-01

    Burning Mouth Syndrome (BMS) is a chronic disorder that predominately affects middle-aged women in the postmenopausal period. The condition is distinguished by burning symptoms of the oral mucosa and the absence of any clinical signs. The etiology of BMS is complex and it includes a variety of factors. Local, systemic and psychological factors such as stress, anxiety and depression are listed among the possible causes of BMS. BMS may sometimes be classified as BMS Type I, II or III. Although this syndrome is not accompanied by evident organic alterations and it does not present health risks, it can significantly reduce the patient's quality of life. This study analyzes the available literature related to BMS, and makes special reference to its therapeutic management. The pages that follow will also discuss the diagnostic criteria that should be respected, etiological factors, and clinical aspects. We used the PubMed database and searched it by using the keywords "burning mouth syndrome", "BMS and review", and "burning mouth and review", in the title or abstract of the publication. BMS treatment usually steers towards the management of the symptoms; however, the specific local factors that could play a significant role in worsening the oral burning sensation should be eradicated. The most widely accepted treatment options that show variable results include tricyclic antidepressants, benzodiazepines and antipsychotic drugs; nevertheless there are other therapies that can also be carried out. Professionals that work in the field of dentistry should formulate standardized symptomatic and diagnostic criteria in order to more easily identify the most effective and reliable strategies in BMS treatment through multidisciplinary research.

  8. Chronic persistent pain after severe burns: a survey of 358 burn survivors.

    PubMed

    Dauber, Andreas; Osgood, Patricia F; Breslau, Alan J; Vernon, Holly L; Carr, Daniel B

    2002-03-01

    To determine the prevalence, characteristics, and effects of chronic persistent pain on burn survivors. Mail survey. Respondents' homes. All members of the Phoenix Society for Burn Survivors. None. Twenty-three questions on the prevalence of pain and its characteristics, including the short form of the McGill-Melzack Pain Questionnaire. Of 1,500 members who received the survey, 358 (24%) responded. Respondents had burns covering an average of 59% of their bodies. Time between the injury and the survey averaged 12 years. On the survey, 52% of respondents reported ongoing burn-related pain, and 46% were able to characterize their pain with one or more of 15 characteristics. Two-thirds (66%) reported that pain interfered with their rehabilitation, and 55% reported that pain interfered with their daily lives. Asked "what makes the pain worse now?," the most frequent reply (15%) was "the weather" (including "hot" or "cold"). Various physical activities (e.g., walking, bicycling) were also mentioned, along with nerve regrowth, contractures, remembering the accident, and depression. "Things that make your pain better now" included "nothing," a variety of over-the-counter analgesics, "rest,"exercise,"yoga,"acupuncture,"family and friends," and "God." In coping with their pain, most respondents found family the most helpful, although nurse(s) received almost as high a rating. Pain associated with burn trauma continues to be of considerable significance in the lives of burn victims long after the initial injury and hospitalization. Little research has been done on this population.

  9. Fischer–Tropsch Synthesis: Characterization Rb Promoted Iron Catalyst

    SciTech Connect

    Sarkar,A.; Jacobs, G.; Ji, Y.; Hamdeh, H.; Davis, B.

    2008-01-01

    Rubidium promoted iron Fischer-Tropsch synthesis (FTS) catalysts were prepared with two Rb/Fe atomic ratios (1.44/100 and 5/100) using rubidium nitrate and rubidium carbonate as rubidium precursors. Results of catalytic activity and deactivation studies in a CSTR revealed that rubidium promoted catalysts result in a steady conversion with a lower deactivation rate than that of the corresponding unpromoted catalyst although the initial activity of the promoted catalyst was almost half that of the unpromoted catalyst. Rubidium promotion results in lower methane production, and higher CO2, alkene and 1-alkene fraction in FTS products. M{umlt o}ssbauer spectroscopic measurements of CO activated and working catalyst samples indicated that the composition of the iron carbide phase formed after carbidization was -Fe5 C2 for both promoted and unpromoted catalysts. However, in the case of the rubidium promoted catalyst, '-Fe2.2C became the predominant carbidic phase as FTS continued and the overall catalyst composition remained carbidic in nature. In contrast, the carbide content of the unpromoted catalyst was found to decline very quickly as a function of synthesis time. Results of XANES and EXAFS measurements suggested that rubidium was present in the oxidized state and that the compound most prevalent in the active catalyst samples closely resembled that of rubidium carbonate.

  10. Ceramic catalyst materials

    SciTech Connect

    Sault, A.G.; Gardner, T.J.; Hanprasopwattanna, A.; Reardon, J.; Datye, A.K.

    1995-08-01

    Hydrous titanium oxide (HTO) ion-exchange materials show great potential as ceramic catalyst supports due to an inherently high ion-exchange capacity which allows facile loading of catalytically active transition metal ions, and an ability to be cast as thin films on virtually any substrate. By coating titania and HTO materials onto inexpensive, high surface area substrates such as silica and alumina, the economics of using these materials is greatly improved, particularly for the HTO materials, which are substantially more expensive in the bulk form than other oxide supports. In addition, the development of thin film forms of these materials allows the catalytic and mechanical properties of the final catalyst formulation to be separately engineered. In order to fully realize the potential of thin film forms of titania and HTO, improved methods for the deposition and characterization of titania and HTO films on high surface area substrates are being developed. By varying deposition procedures, titania film thickness and substrate coverage can be varied from the submonolayer range to multilayer thicknesses on both silica and alumina. HTO films can also be formed, but the quality and reproducibility of these films is not nearly as good as for pure titania films. The films are characterized using a combination of isopropanol dehydration rate measurements, point of zero charge (PZC) measurements, BET surface area, transmission electron microscopy (TEM), and elemental analysis. In order to assess the effects of changes in film morphology on catalytic activity, the films are being loaded with MoO{sub 3} using either incipient wetness impregnation or ion-exchange of heptamolybdate anions followed by calcining. The MoO{sub 3} is then sulfided to form MOS{sub 2}, and tested for catalytic activity using pyrene hydrogenation and dibenzothiophene (DBT) desulfurization, model reactions that simulate reactions occurring during coal liquefaction.

  11. An epidemiological study of 1063 hospitalized burn patients in a tertiary burns centre in Hong Kong.

    PubMed

    Ho, W S; Ying, S Y

    2001-03-01

    A total of 1063 acute burn patients were admitted to the Burns Unit of Prince of Wales Hospital, Hong Kong between March 1993 and February 1999. There were 678 males and 385 females with a male to female ratio of 1.76:1. The median age was 13.1 year-old and the median burn size was 6% total body surface area (TBSA). Pediatric patients under the age of 15 year-old accounted for 550 (51.7%) admissions and 235 (42.7%) of them were toddlers <2 year-old, while adult patients of age above 15 year-old accounted for the other 513 (48.3%) admissions. There was no seasonal variation in admission. Domestic burns resulted in 756 (71.1%) injuries followed by industrial burns that caused 175 (16.5%) admissions. The median hospital stay was 9 days and 54 patients (5.1%) had inhalation injury requiring intubation and ventilatory support. Twenty-four patients died in this series which yielded a mortality rate of 2.3%. The median age for this mortality group was 46.6 year-olds with a median extent of burns of 68% TBSA. There were 16 males and 8 females with a male to female ratio of 2:1. Eighteen (75%) patients had flame burns and 15 (83.3%) of them had inhalation injury. The mortality group had significantly larger burn size (P<0.001), higher incidence of inhalation injury (P<0.001) and older age (P<0.001) compared to the survivors.

  12. Nanostructured porous RuO2/MnO2 as a highly efficient catalyst for high-rate Li-O2 batteries.

    PubMed

    Wang, Guoqing; Huang, Liliang; Huang, Wei; Xie, Jian; Du, Gaohui; Zhang, Shichao; Zhu, Peiyi; Cao, Gaoshao; Zhao, Xinbing

    2015-12-28

    Despite the recent advancements in Li-O(2) (or Li-air) batteries, great challenges still remain to realize high-rate, long-term cycling. In this work, a binder-free, nanostructured RuO(2)/MnO(2) catalytic cathode was designed to realize the operation of Li-O(2) batteries at high rates. At a current density as high as 3200 mA g(-1) (or ∼1.3 mA cm(-2)), the RuO(2)/MnO(2) catalyzed Li-O(2) batteries with LiI can sustain stable cycling of 170 and 800 times at limited capacities of 1000 and 500 mA h g(-1), respectively, with low charge cutoff potentials of ∼4.0 and <3.8 V, respectively. The underlying mechanism of the high catalytic performance of MnO(2)/RuO(2) was also clarified in this work. It was found that with the catalytic effect of RuO(2), Li(2)O(2) can crystallize into a thin-sheet form and realize a conformal growth on sheet-like δ-MnO(2) at a current density up to 3200 mA g(-1), constructing a sheet-on-sheet structure. This crystallization behavior of Li(2)O(2) not only defers the electrode passivation upon discharge but also renders easy decomposition of Li(2)O(2) upon charge, leading to low polarizations and reduced side reactions. This work provides a unique design of catalytic cathodes capable of controlling Li(2)O(2) growth and sheds light on the design of high-rate, long-life Li-O(2) batteries with potential applications in electric vehicles.

  13. Is proportion burned severely related to daily area burned?

    NASA Astrophysics Data System (ADS)

    Birch, Donovan S.; Morgan, Penelope; Kolden, Crystal A.; Hudak, Andrew T.; Smith, Alistair M. S.

    2014-05-01

    The ecological effects of forest fires burning with high severity are long-lived and have the greatest impact on vegetation successional trajectories, as compared to low-to-moderate severity fires. The primary drivers of high severity fire are unclear, but it has been hypothesized that wind-driven, large fire-growth days play a significant role, particularly on large fires in forested ecosystems. Here, we examined the relative proportion of classified burn severity for individual daily areas burned that occurred during 42 large forest fires in central Idaho and western Montana from 2005 to 2007 and 2011. Using infrared perimeter data for wildfires with five or more consecutive days of mapped perimeters, we delineated 2697 individual daily areas burned from which we calculated the proportions of each of three burn severity classes (high, moderate, and low) using the differenced normalized burn ratio as mapped for large fires by the Monitoring Trends in Burn Severity project. We found that the proportion of high burn severity was weakly correlated (Kendall τ = 0.299) with size of daily area burned (DAB). Burn severity was highly variable, even for the largest (95th percentile) in DAB, suggesting that other variables than fire extent influence the ecological effects of fires. We suggest that these results do not support the prioritization of large runs during fire rehabilitation efforts, since the underlying assumption in this prioritization is a positive relationship between severity and area burned in a day.

  14. The Effect of Burn Center Volume on Mortality in a Pediatric Population: An Analysis of the National Burn Repository.

    PubMed

    Hodgman, Erica I; Saeman, Melody R; Subramanian, Madhu; Wolf, Steven E

    2016-01-01

    The effect of burn center volume on mortality has been demonstrated in adults. The authors sought to evaluate whether such a relationship existed in burned children. The National Burn Repository, a voluntary registry sponsored by the American Burn Association, was queried for all data points on patients aged 18 years or less and treated from 2002 to 2011. Facilities were divided into quartiles based on average annual burn volume. Demographics and clinical characteristics were compared across groups, and univariate and multivariate logistic regressions were performed to evaluate relationships between facility volume, patient characteristics, and mortality. The authors analyzed 38,234 patients admitted to 88 unique facilities. Children under age 4 years or with larger burns were more likely to be managed at high-volume and very high-volume centers (57.12 and 53.41%, respectively). Overall mortality was low (0.85%). Comparing mortality across quartiles demonstrated improved unadjusted mortality rates at the low- and high-volume centers compared with the medium-volume and very high-volume centers although univariate logistic regression did not find a significant relationship. However, multivariate analysis identified burn center volume as a significant predictor of decreased mortality after controlling for patient characteristics including age, mechanism of injury, burn size, and presence of inhalation injury. Mortality among pediatric burn patients is low and was primarily related to patient and injury characteristics, such as burn size, inhalation injury, and burn cause. Average annual admission rate had a significant but small effect on mortality when injury characteristics were considered.

  15. Heparin Reduced Mortality and Sepsis in Severely Burned Children

    PubMed Central

    Zayas, G.J.; Bonilla, A.M.; Saliba, M.J

    2007-01-01

    Summary Objectives. In El Salvador, before 1999, morbidity and mortality in severely burned children were high. In 1998, all children with burns of 40% or larger size died and sepsis was found. With heparin use in 1999, some similarly burned children survived, and sepsis, pain, procedures, and scars were noted to be less. This retrospective study presents the details. Methods. A study was conducted at the National Children's Hospital in El Salvador of all children with burns over 20% size treated in 1998, when no heparin was used, and in 1999, when heparin was added to burns treatment, using an ethics committee approved protocol in use in twelve other countries. Sodium aqueous heparin solution USP from an intestinal source was infused intravenously and applied topically onto burn surfaces and within blisters for the first 1-3 days post-burn. Then heparin, in diminishing doses, was continued only topically until healing. The treatments in 1998 and 1999 were otherwise the same, except that fewer procedures were needed in 1999. Results. There were no significant differences in gender, age, weight, burn aetiology, or burn size between the burned children in 1998 and those in 1999. Burn pain was relieved and pain medicine was not needed in children treated with heparin in 1999. In 1998, one child survived who had a 35% size burn, and the eight children died who had burns of 40% and over. The survival rate was one out of nine (11%). The average burn size was 51.7%. With heparin use in 1999, six of the ten children survived burns of 50.7% average size. The increase in survival with heparin from 11% to 60% and, therefore, the decrease in mortality from 89% to 40% were significant (p < 0.04). Clinical symptoms and positive blood cultures documented bacterial sepsis in the nine children in 1998. In 1999, the blood cultures for sepsis were positive in the four children who died and negative in the six who survived. The nine versus four differences in the incidence of sepsis

  16. Prescribed burning consumes key forest structural components: implications for landscape heterogeneity.

    PubMed

    Holland, Greg J; Clarke, Michael F; Bennett, Andrew F

    2017-04-01

    Prescribed burning to achieve management objectives is a common practice in fire-prone regions worldwide. Structural components of habitat that are combustible and slow to develop are particularly susceptible to change associated with prescribed burning. We used an experimental, "whole-landscape" approach to investigate the effect of differing patterns of prescribed burning on key habitat components (logs, stumps, dead trees, litter cover, litter depth, and understorey vegetation). Twenty-two landscapes (each ~100 ha) were selected in a dry forest ecosystem in southeast Australia. Experimental burns were conducted in 16 landscapes (stratified by burn extent) while six served as untreated controls. We measured habitat components prior to and after burning. Landscape burn extent ranged from 22% to 89% across the 16 burn treatments. With the exception of dead standing trees (no change), all measures of habitat components declined as a consequence of burning. The degree of loss increased as the extent to which a landscape was burned also increased. Prescribed burning had complex effects on the spatial heterogeneity (beta diversity) of structural components within landscapes. Landscapes that were more heterogeneous pre-fire were homogenized by burning, while those that were more homogenous pre-fire tended to display greater differentiation post-burning. Thus, the notion that patch mosaic burning enhances heterogeneity at the landscape-scale depends on prior conditions. These findings have important management implications. Where prescribed burns must be undertaken, effects on important resources can be moderated via control of burn characteristics (e.g., burn extent). Longer-term impacts of prescribed burning will be strongly influenced by the return interval, given the slow rate at which some structural components accumulate (decades to centuries). Management of habitat structural components is important given the critical role they play in (1) provision of habitat

  17. Hydroxide catalysts for lignin depolymerization

    DOEpatents

    Beckham, Gregg T.; Biddy, Mary J.; Chmely, Stephen C.; Sturgeon, Matthew

    2017-04-25

    Solid base catalysts and their use for the base-catalyzed depolymerization (BCD) of lignin to compounds such as aromatics are presented herein. Exemplary catalysts include layered double hydroxides (LDHs) as recyclable, heterogeneous catalysts for BCD of lignin.

  18. The year in burns 2011.

    PubMed

    Wolf, Steven E; Arnoldo, Brett D

    2012-12-01

    For 2011, approximately 1746 original research articles in burns were published in English in scientific journals. This article reviews those with the most potential impact on for burn therapeutics and outcomes according to the Editor of one of the major journals (Burns) and his colleague. As done previously, articles were found and divided into these topic areas: epidemiology of injury and burn prevention, wound and scar characterisation, acute care and critical care, inhalation injury, infection, psychological considerations, pain and itching management, rehabilitation and long-term outcomes, and burn reconstruction. Each selected article is mentioned briefly with editorial comment.

  19. Determination of PM10 and its ion composition emitted from biomass burning in the chamber for estimation of open burning emissions.

    PubMed

    Sillapapiromsuk, Sopittaporn; Chantara, Somporn; Tengjaroenkul, Urai; Prasitwattanaseree, Sukon; Prapamontol, Tippawan

    2013-11-01

    Biomass samples including agricultural waste (rice straw and maize residue) and forest leaf litter were collected from Chiang Mai Province, Thailand for the burning experiment in the self-designed stainless steel chamber to simulate the emissions of PM10. The burning of leaf litter emitted the highest PM10 (1.52±0.65 g kg(-1)). The PM10-bound ions emitted from the burning of rice straw and maize residue showed the same trend, which was K(+)>Cl(-)>SO4(2-)>NH4(+)>NO3(-). However, the emissions from maize residue burning were ~1.5-2.0 times higher than those from the rice straw burning. The ion content emitted from leaf litter burning was almost the same for all ion species. Noticeably, K(+) and Cl(-) concentrations were ~2-4 times lower than those emitted from agricultural waste burning. It can be deduced that K(+) and Cl(-) were highly emitted from agricultural waste burning due to the use of fertilizer and herbicides in the field, respectively. Based on emission values obtained from the chamber, the pollutant emission rate from open burning was calculated. Burned areas in Chiang Mai Province were 3510 and 866 km(2) in 2010 and 2011, respectively. Forest burning was 71-88%, while agricultural land burning accounted for 12-29% (rice field: crop field=1:3) of total burned area. Therefore, emissions of PM10 from open burning in Chiang Mai were 3051 ton (2010) and 705 ton (2011). Major ions emitted from agricultural waste burning were found to be K(+) and Cl(-), while those from forest burning were SO4(2-) and K(+).

  20. Longitudinal burn scar quantification.

    PubMed

    Nedelec, Bernadette; Correa, José A; de Oliveira, Ana; LaSalle, Leo; Perrault, Isabelle

    2014-12-01

    Quantitative studies of the clinical recovery of burn scars are currently lacking. Previous reports validate the objective, precise, diagnostic capabilities of high-frequency ultrasound to measure thickness, the Cutometer(®) to measure pliability and the Mexameter(®) to measure erythema and pigmentation of scars. Thus, we prospectively quantified clinical characteristics of patient-matched, after burn hypertrophic scar (HSc), donor site scar (D) and normal skin (N) using these instruments. One investigator measured 3 sites (HSc, D, N) in 46 burn survivors at 3, 6, and 12 months after-burn. A mixed model regression analysis, adjusting p-values for multiplicity of testing, was used to compare means among sites and time points. Participants were 41.2±13.5 years old, 87% males, predominantly Caucasian, with an average of 19.5% body surface area burned. HSc thickness decreased significantly between 3 and 6, 6 and 12, and 3 and 12 months (all p<0.0001), but remained thicker than D and N skin (all p<0.0001). Pliability differed significantly between HSc, D and N sites at all time points (all p<0.0001), with HSc and D increasing between 3 and 12 months (p<0.05) but not reaching normal. HSc and D sites were significantly more erythematous than normal skin (p<0.05) at 3 and 6 months but D sites approached normal by 12 months. The only time points at which pigmentation significantly differed were the HSc and D sites at 6 months. Thickness, pliability, erythema and pigmentation of N skin remained similar over the 12 months. We found that post-burn HSc thickness, pliability and erythema differed significantly from D and N skin at 3, 6, and 12 months and does not return to normal by 12 months after-injury; however, significant improvements towards normal can be expected. Donor sites are redder than normal skin at 3 and 6 months but can be expected to return to normal by 12 months. Although the color of HSc and D sites change markedly with time these color changes are

  1. Chemical Debridement of Burns

    PubMed Central

    Levenson, Stanley M.; Kan, Dorinne; Gruber, Charles; Crowley, Leo V.; Lent, Richard; Watford, Alvin; Seifter, Eli

    1974-01-01

    The development of effective, non-toxic (local and systemic) methods for the rapid chemical (enzymatic and non-enzymatic) debridement of third degree burns would dramatically reduce the morbidity and mortality of severely burned patients. Sepsis is still the major cause of death of patients with extensive deep burns. The removal of the devitalized tissue, without damage to unburned skin or skin only partially injured by burning, and in ways which would permit immediate (or very prompt) skin grafting, would lessen substantially the problems of sepsis, speed convalescence and the return of these individuals to society as effective human beings, and would decrease deaths. The usefulness and limitations of surgical excision for patients with extensive third degree burns are discussed. Chemical debridement lends itself to complementary use with surgical excision and has the potential advantage over surgical excision in not requiring anesthesia or a formal surgical operation. The authors' work with the chemical debridement of burns, in particular the use of Bromelain, indicates that this approach will likely achieve clinical usefulness. The experimental studies indicate that rapid controlled debridement, with minimal local and systemic toxicity, is possible, and that effective chemotherapeutic agents may be combined with the Bromelain without either interfering with the actions of the other. The authors believe that rapid (hours) debridement accomplished by the combined use of chemical debriding and chemotherapeutic agents will obviate the possibility of any increase in infection, caused by the use of chemical agents for debridement, as reported for Paraenzyme21 and Travase.39,48 It is possible that the short term use of systemic antibiotics begun just before and continued during, and for a short time after, the rapid chemical debridement may prove useful for the prevention of infection, as appears to be the case for abdominal operations of the clean-contaminated and

  2. Burns in mobile home fires--descriptive study at a regional burn center.

    PubMed

    Mullins, Robert F; Alarm, Badrul; Huq Mian, Mohammad Anwarul; Samples, Jancie M; Friedman, Bruce C; Shaver, Joseph R; Brandigi, Claus; Hassan, Zaheed

    2009-01-01

    Death from fires and burns are the sixth most common cause of unintentional injury death in the United States. More than (3/4) of burn deaths occurring in the United States are in the home. Mobile home fires carry twice the death rate as other dwellings. The aim of the study was to describe the characteristics of deaths and injuries in mobile home fire admitted in a regional Burn Center and to identify possible risk factors. A cross-sectional retrospective study was carried out among all burn patients admitted to a regional Burn Center between January 2002 and December 2004 (3469 patients). The study included patients who suffered a burn injury from a mobile home fire. The demographic characteristics of the patients, location of mobile home, associated inhalation injury, source of fire, comorbidity of the victims, employment status, insurance status, family history of burns, and outcomes of the treatment were incorporated in a data collection record. There were 65 burn patients in mobile home fires admitted to the Burn Center during the studied period. The average age of the patients was 39 years (ranging from 2 to 81 years, SD=16.06), 77% were male, 67% were white, and 79% were the residents in the suburban areas of Georgia, South Carolina, North Carolina, and Florida. The average TBSA of burns was about 21% (ranging from 1 to 63%, SD=17.66), 63% of the patients had associated inhalation, three inhalation injury only, and 69% patients required ventilator support. The average length of stay per TBSA percentage of burn was 1.01 days (P=0.00), controlling for age, preexisting medical comorbidities, and inhalation injury. About 88% of the patients had preexisting medical comorbid conditions, 74% were smokers, 64% reported as alcoholic, and 72% had at least some form of health insurance coverage. In 40% of the cases, the cause of the fire was unknown, 31% were caused by accidental explosions, such as electric, gasoline, or kerosene appliances, and 29% were due to other

  3. Prehospital cooling of severe burns: Experience of the Emergency Department at Edendale Hospital, KwaZulu-Natal, South Africa.

    PubMed

    Fiandeiro, D; Govindsamy, J; Maharaj, R C

    2015-06-01

    Early cooling with 10 - 20 minutes of cool running water up to 3 hours after a burn has a direct impact on the depth of the burn and therefore on the clinical outcome of the injury. An assessment of the early cooling of burns is essential to improve this aspect of burns management. To assess the rates and adequacy of prehospital cooling received by patients with severe burns before presentation to the Emergency Department (ED) at Edendale Hospital, Pietermaritzburg, South Africa. Patients with inadequate prehospital cooling who presented to the ED within 3 hours were also identified. A retrospective reviewof the burns database for all the patients with severe burns admitted from the ED at Edendale Hospital from September 2012 to August 2013 was undertaken. Demographic details, characteristics and timing of the burns, and presentation were correlated with burn cooling. Ninety patients were admitted with severe burns. None received sufficient cooling of their burns, 25.6% received cooling of inadequate duration, and 32.3% arrived at the ED within 3 hours after the burn with either inadequate or no cooling. The median time to presentation to the ED after the burn was 260 minutes. Appropriate cooling of severe burns presenting to Edendale Hospital is inadequate. Education of the community and prehospital healthcare workers about the iiportance of early appropriate cooling of severe burns is required. Many patients would benefit from cooling of their burns in the ED, and facilities should be provided for this vital function.

  4. The optimal time for early excision in major burn injury.

    PubMed

    Muangman, Pornprom; Sullivan, Stephen R; Honari, Shari; Engrav, Lorenz H; Heimbach, David M; Gibran, Nicole S

    2006-01-01

    Early excision and grafting (E&G) drastically changed burn care in America by reducing morbidity, mortality and hospital length of stay (LOS). The present study was intended to determine whether an optimal time window exists between resuscitation and wound sepsis for the first E&G in a patient with a large burn. The authors conducted a retrospective study of patients admitted between January 1994 and December 2000 with > or = 40% TBSA burns and at least 1 E&G procedure. Patients were grouped according to the day of their first operation. Patients allowed to heal indeterminate burns prior to excision and grafting of deep partial or full thickness burns were grouped as > or = d7 and were excluded from the present study. The authors correlated the time of first excision with infection, mortality and LOS. Seventy-five patients were identified and 12 patients allowed to heal indeterminate burn prior to excision and grafting of deep partial or full thickness burns were excluded. Sixty-three remaining patients included 51 males and 12 females. Mean burn size was 49% of total body surface area (TBSA) (44% deep partial or full thickness) and the mean age was 36 years. There were 61 flame (2 combined with electrical injuries), 1 scald and 1 chemical burn. Twelve died (19%) and 52 patients developed 121 infections. Whereas there was no statistical difference in mortality for patients operated on different days (p > 0.2), 60% of patients operated within the first 48 hours after injury died; this was not significant due to a small patient number The present data suggest that patients who undergo early excision and grafting within seven days following a major burn > or = 40% TBSA have equivalent infection or mortality rates regardless of when the first operation occurs between post burn day(PBD) 2 and PBD 7 (p > 0.2).

  5. Epidemiological analysis of burn patients in east Bulgaria.

    PubMed

    Zayakova, Yolanda; Vajarov, Ivailo; Stanev, Anton; Nenkova, Natalia; Hristov, Hristo

    2014-06-01

    The purpose of the study was to identify the basic epidemiological characteristics of burn patients in East Bulgaria, as well as to analyze trends in burns in the region over the last decade. Retrospective data of burn patients treated at Military Hospital-Varna, in the period January 2002-December 2011, was reviewed and statistically interpreted in terms of patients and burn demographics; etiology; place of incidents; hospital stay and mortality. Trends were observed for the entire period and comparative analyses of patients' data were made between two periods: first - 2002-2006 and second 2007-2011. A total of 2627 burn patients, median age 41 years (IQR 9-61) were admitted to our burn unit. For the entire period the most affected age groups were ≤ 4 years (21.6%) and ≥ 65 years (21.1%). Hospitalized patients increased in the second period (n = 1701) compared to the first one (n = 926), while the size of total burn surface area decreased (first period - 9.8% vs. second period - 10.6%). Scald (51%) and flame (23.8%) were the most frequent aetiological agents for both periods. Work related burns reduced in the second period (9.4% vs. 4.9%), while home burns (90.6 vs. 95.1%) increased. Hospital stay declined from 17 days (2002-2006) to 7 days (2007-2011), whereas mortality rate slightly increased (first period - 2.3% vs. second period - 3.6%). Burns remain a significant health problem in Bulgaria. The future preventive actions should take into account the observed changes in burn demographics and target the most vulnerable groups. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.

  6. Nanostructured catalyst supports

    DOEpatents

    Zhu, Yimin; Goldman, Jay L.; Qian, Baixin; Stefan, Ionel C.

    2012-10-02

    The present invention relates to SiC nanostructures, including SiC nanopowder, SiC nanowires, and composites of SiC nanopowder and nanowires, which can be used as catalyst supports in membrane electrode assemblies and in fuel cells. The present invention also relates to composite catalyst supports comprising nanopowder and one or more inorganic nanowires for a membrane electrode assembly.

  7. Nanostructured catalyst supports

    DOEpatents

    Zhu, Yimin; Goldman, Jay L.; Qian, Baixin; Stefan, Ionel C.

    2015-09-29

    The present invention relates to SiC nanostructures, including SiC nanopowder, SiC nanowires, and composites of SiC nanopowder and nanowires, which can be used as catalyst supports in membrane electrode assemblies and in fuel cells. The present invention also relates to composite catalyst supports comprising nanopowder and one or more inorganic nanowires for a membrane electrode assembly.

  8. Reducible oxide based catalysts

    DOEpatents

    Thompson, Levi T.; Kim, Chang Hwan; Bej, Shyamal K.

    2010-04-06

    A catalyst is disclosed herein. The catalyst includes a reducible oxide support and at least one noble metal fixed on the reducible oxide support. The noble metal(s) is loaded on the support at a substantially constant temperature and pH.

  9. Fischer-Tropsch Catalysts

    NASA Technical Reports Server (NTRS)

    White, James H. (Inventor); Taylor, Jesse W. (Inventor)

    2008-01-01

    Catalyst compositions and methods for F-T synthesis which exhibit high CO conversion with minor levels (preferably less than 35% and more preferably less than 5%) or no measurable carbon dioxide generation. F-T active catalysts are prepared by reduction of certain oxygen deficient mixed metal oxides.

  10. [Burn out of formal carers in geriatric facilities].

    PubMed

    Courty, Bénédicte; Bouisson, Jean; Compagnone, Philippe

    2004-09-01

    From a person-centered perspective, this study investigates the relationship between burn out and anxiety-depression, among geriatric caregivers, according to the helplessness-hopelessness theory. The population studied consists of 150 caregivers, drawn from different geriatric facilities throughout France. Data was collected from three self-administered questionnaires: the Maslach Burnout Inventory (MBI) measures burn out, whereas the STAI measures anxiety and the CES-D assesses symptoms of depression. These tools have been used to analyze the effects of several potential vulnerability factors. Three distinct groups have been identified by cluster analysis on the MBI's dimensions. Subjects from the first cluster (n = 88) did not suffer from burn out, whereas subjects from group 2 (n = 46) and group 3 (n = 16) have been rated "at risk" and "at high risk" of developing burn out. The three groups have significantly different levels of anxiety and depression. Age, profession and type of facility appeared as vulnerability factors for professional burn out.

  11. Method and apparatus to measure the depth of skin burns

    DOEpatents

    Dickey, Fred M.; Holswade, Scott C.

    2002-01-01

    A new device for measuring the depth of surface tissue burns based on the rate at which the skin temperature responds to a sudden differential temperature stimulus. This technique can be performed without physical contact with the burned tissue. In one implementation, time-dependent surface temperature data is taken from subsequent frames of a video signal from an infrared-sensitive video camera. When a thermal transient is created, e.g., by turning off a heat lamp directed at the skin surface, the following time-dependent surface temperature data can be used to determine the skin burn depth. Imaging and non-imaging versions of this device can be implemented, thereby enabling laboratory-quality skin burn depth imagers for hospitals as well as hand-held skin burn depth sensors the size of a small pocket flashlight for field use and triage.

  12. A Computer Program to Evaluate Experimental Therapies for Treating Burned Patients

    PubMed Central

    Flora, Jairus D.; Flora, Sharyl Ann

    1980-01-01

    Determining the worth of new therapies for burn patients has been difficult because of the rarity of the burn injury and the disparate survival chances associated with different sizes of burns. Recently a burn survival model has been developed that estimates the risk of death from a burn as a function of the patient's age, sex, area of full thickness (third degree) burn, area of partial thickness burn, involvement of the perineum, and time from burn to admission. An alternative risk model uses the total area burned in place of the areas of partial thickness burn and full thickness burn, and is appropriate if the amount of full thickness burn is not determined accurately. This paper describes a program that uses these risk models to correct or standardize for demographic and severity factors, then, after that adjustment, tests whether a group of burn patients who received a new or experimental therapy shows a significantly better survival rate than that predicted by a baseline model. The program is a simple one written in Fortran for easy adaptation to other computer systems.

  13. Temperature Responses during Exercise in a Hot Environment in Severely Burned Children

    PubMed Central

    McEntire, Serina J.; Chinkes, David L.; Herndon, David N.; Suman, Oscar E.

    2014-01-01

    Objective We have previously described thermoregulatory responses of severely burned children during submaximal exercise in a thermoneutral environment. However, the thermoregulatory response of burned children to exercise in the heat is not well understood and could have important safety implications for rehabilitation. Study design Children (n=10) with >40% total body surface area burns and non-burned children (n=10) performed a 30 minute bout of treadmill exercise at 75% of their peak aerobic power in a heated environment. Intestinal temperature, burned and unburned skin temperature, and heart rate were recorded pre-exercise, every 2 minutes during exercise, and during recovery. Results Three of the 10 burned children completed the exercise bout in the heat; however, all of the non-burned children completed the 30 minute bout. One burned child reached a core body temperature > 39°C at minute 23. Burned children had a significantly higher core body temperature thru the first 12 minutes of exercise compared to non-burned children. However, 9 of 10 (90%) burned children did not become hyperthermic during exercise in the heat. Conclusion Specific to this study, hyperthermia did not typically occur in burned children, relative to non-burned children. Whether this is due to an intolerance to exercise in the heat or to an inability to generate sufficient heat during exercise needs to be explored further. PMID:20616652

  14. Segmentation and classification of burn images by color and texture information.

    PubMed

    Acha, Begoña; Serrano, Carmen; Acha, José I; Roa, Laura M

    2005-01-01

    In this paper, a burn color image segmentation and classification system is proposed. The aim of the system is to separate burn wounds from healthy skin, and to distinguish among the different types of burns (burn depths). Digital color photographs are used as inputs to the system. The system is based on color and texture information, since these are the characteristics observed by physicians in order to form a diagnosis. A perceptually uniform color space (L*u*v*) was used, since Euclidean distances calculated in this space correspond to perceptual color differences. After the burn is segmented, a set of color and texture features is calculated that serves as the input to a Fuzzy-ARTMAP neural network. The neural network classifies burns into three types of burn depths: superficial dermal, deep dermal, and full thickness. Clinical effectiveness of the method was demonstrated on 62 clinical burn wound images, yielding an average classification success rate of 82%.

  15. Assessing burn depth in tattooed burn lesions with LASCA Imaging.

    PubMed

    Krezdorn, N; Limbourg, A; Paprottka, F J; Könneker; Ipaktchi, R; Vogt, P M

    2016-09-30

    Tattoos are on the rise, and so are patients with tattooed burn lesions. A proper assessment with regard to burn depth is often impeded by the tattoo dye. Laser speckle contrast analysis (LASCA) is a technique that evaluates burn lesions via relative perfusion analysis. We assessed the effect of tattoo skin pigmentation on LASCA perfusion imaging in a multicolour tattooed patient. Depth of burn lesions in multi-coloured tattooed and untattooed skin was assessed using LASCA. Relative perfusion was measured in perfusion units (PU) and compared to various pigment colours, then correlated with the clinical evaluation of the lesion. Superficial partial thickness burn (SPTB) lesions showed significantly elevated perfusion units (PU) compared to normal skin; deep partial thickness burns showed decreased PU levels. PU of various tattoo pigments to normal skin showed either significantly lower values (blue, red, pink) or significantly increased values (black) whereas orange and yellow pigment showed values comparable to normal skin. In SPTB, black and blue pigment showed reduced perfusion; yellow pigment was similar to normal SPTB burn. Deep partial thickness burn (DPTB) lesions in tattoos did not show significant differences to normal DPTB lesions for black, green and red. Tattoo pigments alter the results of perfusion patterns assessed with LASCA both in normal and burned skin. Yellow pigments do not seem to interfere with LASCA assessment. However proper determination of burn depth both in SPTB and DPTB by LASCA is limited by the heterogenic alterations of the various pigment colours.

  16. Assessing burn depth in tattooed burn lesions with LASCA Imaging

    PubMed Central

    Krezdorn, N.; Limbourg, A.; Paprottka, F.J.; Könneker; Ipaktchi, R.; Vogt, P.M

    2016-01-01

    Summary Tattoos are on the rise, and so are patients with tattooed burn lesions. A proper assessment with regard to burn depth is often impeded by the tattoo dye. Laser speckle contrast analysis (LASCA) is a technique that evaluates burn lesions via relative perfusion analysis. We assessed the effect of tattoo skin pigmentation on LASCA perfusion imaging in a multicolour tattooed patient. Depth of burn lesions in multi-coloured tattooed and untattooed skin was assessed using LASCA. Relative perfusion was measured in perfusion units (PU) and compared to various pigment colours, then correlated with the clinical evaluation of the lesion. Superficial partial thickness burn (SPTB) lesions showed significantly elevated perfusion units (PU) compared to normal skin; deep partial thickness burns showed decreased PU levels. PU of various tattoo pigments to normal skin showed either significantly lower values (blue, red, pink) or significantly increased values (black) whereas orange and yellow pigment showed values comparable to normal skin. In SPTB, black and blue pigment showed reduced perfusion; yellow pigment was similar to normal SPTB burn. Deep partial thickness burn (DPTB) lesions in tattoos did not show significant differences to normal DPTB lesions for black, green and red. Tattoo pigments alter the results of perfusion patterns assessed with LASCA both in normal and burned skin. Yellow pigments do not seem to interfere with LASCA assessment. However proper determination of burn depth both in SPTB and DPTB by LASCA is limited by the heterogenic alterations of the various pigment colours. PMID:28149254

  17. [Hydrofluoric acid burns].

    PubMed

    Holla, Robin; Gorter, Ramon R; Tenhagen, Mark; Vloemans, A F P M Jos; Breederveld, Roelf S

    2016-01-01

    Hydrofluoric acid is increasingly used as a rust remover and detergent. Dermal contact with hydrofluoric acid results in a chemical burn characterized by severe pain and deep tissue necrosis. It may cause electrolyte imbalances with lethal consequences. It is important to identify high-risk patients. 'High risk' is defined as a total affected body area > 3% or exposure to hydrofluoric acid in a concentration > 50%. We present the cases of three male patients (26, 31, and 39 years old) with hydrofluoric acid burns of varying severity and describe the subsequent treatments. The application of calcium gluconate 2.5% gel to the skin is the cornerstone of the treatment, reducing pain as well as improving wound healing. Nails should be thoroughly inspected and possibly removed if the nail is involved, to ensure proper healing. In high-risk patients, plasma calcium levels should be evaluated and cardiac monitoring is indicated.

  18. 'Burns Cliff' Color Panorama

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site] Click on the image for 'Burns Cliff' Color Panorama (QTVR)

    NASA's Mars Exploration Rover Opportunity captured this view of 'Burns Cliff' after driving right to the base of this southeastern portion of the inner wall of 'Endurance Crater.' The view combines frames taken by Opportunity's panoramic camera between the rover's 287th and 294th martian days (Nov. 13 to 20, 2004).

    This is a composite of 46 different images, each acquired in seven different Pancam filters. It is an approximately true-color rendering generated from the panoramic camera's 750-nanometer, 530-nanometer and 430-nanometer filters. The mosaic spans more than 180 degrees side to side. Because of this wide-angle view, the cliff walls appear to bulge out toward the camera. In reality the walls form a gently curving, continuous surface.

  19. [Burning mouth syndrome (glossalgia)].

    PubMed

    2014-01-01

    Burning mouth syndrome (glossalgia) is manifested by oral pin and tingling sensations, numbness and even burning and severe pains, more frequently in the tongue. Unpleasant sensations may involve the anterior two thirds of the tongue or be extended to the front part of the hard palate and the mucous membrane of the lower lip. This condition is characterized by "mirror" and "food dominant" symptoms, disordered salivation, dysgeusia, or psychological disorders. The disease shows a chronic course. Its etiology may be multifactorial. There are no universally accepted diagnostic criteria; the diagnosis of glossalgia is made to rule out all other causes. A thorough examination should be conducted to establish a differential diagnosis. Glossalgia occurs primarily in middle-aged and elderly people. Women get sick much more frequently than men of the same age. Glossalgia remains difficult to treat. Continuous symptomatic treatment and follow-up help relieve its symptoms.

  20. Organometallic polymerization catalysts

    SciTech Connect

    Waymouth, R.M.

    1993-12-31

    Well-defined transition metal catalysts have resulted in exciting new opportunities in polymer synthesis. The stereochemistry of vinyl polymers can be rationally controlled with choice of the appropriate catalysts. Studies with optically active catalyst precursors have revealed considerable information on the absolute stereochemistry of olefin polymerization and have led to the synthesis of novel chiral polyolefins. The development of homogeneous olefin metathesis catalysts has also led to a variety of well-defined new polymer structures with controlled molecular weight and molecular weight distribution. Recent advances in understanding the mechanisms and stereochemistry of homogeneous transition metal catalyzed polymerization will be discussed. The ability to control polymer structure through catalyst design presents exciting opportunities in the synthesis of {open_quotes}tailor-made{close_quotes} macromolecules.