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Sample records for high burn rate

  1. High burn rate solid composite propellants

    Science.gov (United States)

    Manship, Timothy D.

    High burn rate propellants help maintain high levels of thrust without requiring complex, high surface area grain geometries. Utilizing high burn rate propellants allows for simplified grain geometries that not only make production of the grains easier, but the simplified grains tend to have better mechanical strength, which is important in missiles undergoing high-g accelerations. Additionally, high burn rate propellants allow for a higher volumetric loading which reduces the overall missile's size and weight. The purpose of this study is to present methods of achieving a high burn rate propellant and to develop a composite propellant formulation that burns at 1.5 inches per second at 1000 psia. In this study, several means of achieving a high burn rate propellant were presented. In addition, several candidate approaches were evaluated using the Kepner-Tregoe method with hydroxyl terminated polybutadiene (HTPB)-based propellants using burn rate modifiers and dicyclopentadiene (DCPD)-based propellants being selected for further evaluation. Propellants with varying levels of nano-aluminum, nano-iron oxide, FeBTA, and overall solids loading were produced using the HTPB binder and evaluated in order to determine the effect the various ingredients have on the burn rate and to find a formulation that provides the burn rate desired. Experiments were conducted to compare the burn rates of propellants using the binders HTPB and DCPD. The DCPD formulation matched that of the baseline HTPB mix. Finally, GAP-plasticized DCPD gumstock dogbones were attempted to be made for mechanical evaluation. Results from the study show that nano-additives have a substantial effect on propellant burn rate with nano-iron oxide having the largest influence. Of the formulations tested, the highest burn rate was a 84% solids loading mix using nano-aluminum nano-iron oxide, and ammonium perchlorate in a 3:1(20 micron: 200 micron) ratio which achieved a burn rate of 1.2 inches per second at 1000

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

    Science.gov (United States)

    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.

  3. High Burn Rate Hybrid Fuel for Improved Grain Design Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A novel type of fuel providing high burning rate for hybrid rocket applications is proposed. This fuel maintains a hydrodynamically rough surface to...

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

    Energy Technology Data Exchange (ETDEWEB)

    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

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  8. PBXN-110 Burn Rate Estimate

    Energy Technology Data Exchange (ETDEWEB)

    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.

  9. Toddlers at High Risk of Chemical Eye Burns

    Science.gov (United States)

    ... fullstory_160258.html Toddlers at High Risk of Chemical Eye Burns: Study Access to household cleaning products to blame, ... and 2 years have relatively high rates of chemical eye burns, with everyday cleaners a common cause, researchers say. ...

  10. Burning Rate Characteristics of Magnesium Sodium Nitrate Propellants

    Directory of Open Access Journals (Sweden)

    R. Bhaskara Rao

    1992-07-01

    Full Text Available The combustion phenomena of Mg-NaNO/sub 3/ propellants have been studied. Results of burning rate at different mixture ratios and particle sizes indicate that the compositions containing finer particle size (50 millimicron NaNO/sub 3/ give higher burning rate at high fuel content of the mixture than at the stoichiometric ratio; whereas the compositions with coarser particle size (250 millimicron NaNO/sub 3/ show increasing burning rate with increasing oxidiser content and give a maximum at stoichiometric point. Thermal decomposition results indicate that the condensed phase heat release at the propellant surface and the reactions in the vapour phase are responsible for variations in the burning rate. The decomposition products of finer size NaNO/sub 3/, react with Mg before Mg particles acquire sufficient energy for ignition, and lead to condensed phase heat release. This heat is maximum at high fuel content and causes high burning rate with low pressure and temperature sensitivity. The increase in the oxidiser content reduces the condensed phase heat due to formation of metal agglomerates and causes lower burning rate with high pressure and temperature sensitivity. After the Mg particles acquire sufficient energy for ignition the decomposition products of coarser size NaNO/sub 3/ diffuse out along with Mg and react in the vapour phase. This causes an increase of burning rate with increase in the oxidiser content of the mixture up to the stoichiometric ratio with a pressure and temperature dependence.

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

    Science.gov (United States)

    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.

  12. Burning rate characteristics of CMDB propellants

    Energy Technology Data Exchange (ETDEWEB)

    Swaminathan, V.; Soosai Marian, M. (Vikram Sarabhai Space Centre, Trivandrum (India). Propellant Engineering Div.)

    1979-10-01

    The object of this paper is to obtain expressions for the burning rate pressure exponent and the temperature sensitivity of AP-based and HMX-based CMDB propellants in terms of the respective physical constants on the basis of a recently developed model of combustion for CMDB propellants and to examine the effects, if any, on these two parameters, of the changes in propellant composition, AP particle size and pressure. Computer programs were developed for this purpose and the results obtained for typical sets of input data presented in the paper. While the results of the calculation indicate a markedly strong dependence of the pressure exponent and the temperature sensitivity on pressure and composition for both AP-based and HMX-based CMDB propellants, the parameters are characterized by far lesser dependence on AP particle size for the AP-based propellant.

  13. Burning Rate Studies of Energetic Double Base Propellants

    Directory of Open Access Journals (Sweden)

    V. K. Bhat

    1986-01-01

    Full Text Available A systematic study was carried out on the combustion characteristics of CMDB propellants containing ammonium nitrate, ammonium perchlorate, potassium nitrate, potassium perchlorate, RDX and PETN. While ammonium and potassium perchlorates increased burning rates, other additives maintained either the same burning rate or reduced burning rates marginally. Propellants containing these additives showed marginally higher peak temperatures, indicating interaction among the species of double base propellant decomposition and those of additives.

  14. Effects of normal acceleration on transient burning rate augmentation of an aluminized solid propellant

    Science.gov (United States)

    Northam, G. B.

    1972-01-01

    Instantaneous burning rate data for a polybutadiene acrylic acid propellant, containing 16 weight percent aluminum, were calculated from the pressure histories of a test motor with 96.77 sq cm of burning area and a 5.08-cm-thick propellant web. Additional acceleration tests were conducted with reduced propellant web thicknesses of 3.81, 2.54, and 1.27 cm. The metallic residue collected from the various web thickness tests was characterized by weight and shape and correlated with the instantaneous burning rate measurements. Rapid depressurization extinction tests were conducted in order that surface pitting characteristics due to localized increased burning rate could be correlated with the residue analysis and the instantaneous burning rate data. The acceleration-induced burning rate augmentation was strongly dependent on propellant distance burned, or burning time, and thus was transient in nature. The results from the extinction tests and the residue analyses indicate that the transient rate augmentation was highly dependent on local enhancement of the combustion zone heat feedback to the surface by the growth of molten residue particles on or just above the burning surface. The size, shape, and number density of molten residue particles, rather than the total residue weight, determined the acceleration-induced burning rate augmentation.

  15. 含FOX-12的高燃速HTPB推进剂性能%Properties of high burning rate HTPB propellant containing FOX-12

    Institute of Scientific and Technical Information of China (English)

    胥会祥; 赵凤起; 庞维强; 李勇宏; 杨建; 刘子如

    2011-01-01

    为降低高燃速HTPB推进剂的感度,探讨了N-脒基脲二硝酰胺盐(FOX-12)对该推进剂能量性能、燃烧性能和安全性能的影响.结果表明,FOX-12使推进剂的燃温(Tc)、平均相对分子质量(M)和爆热(Qv)均降低,但对推进剂比冲(Isp)的影响较小,FOX-12含量为5%时,Isp降低约0.458%.随FOX-12含量增加,相同压力下的推进剂燃速降低,但推进剂摩擦感度、撞击感度和静电火花感度均逐步降低;当FOX-12含量为5%,在4~10 MPa下,推进剂燃速的降幅最大为4.75%,而摩擦感度由96%降至68%.由于FOX-12的真空安定性差于AP,含FOX-12推进剂的热安定性降低,但能满足应用要求.FOX-12的氧平衡为负,这可能使推进剂氧化性分解产物与HTPB粘合剂、Al等组分的反应速率降低,促使推进剂耐烤燃的性能增强.总之,FOX-12能显著提高高燃速HTPB推进剂的应用安全性.%In order to reduce sensitivity of high burning rate HTPB propellant, the effect of N-guanylurea-dianitramide ( FOX-12) on energy performance,combustion characteristic,and security performance of the propellant were discussed. Results show thatFOX-12 leads to the decrease of Tc ,M and Q, ,but has less effect on Iap of propellants. When the content of FOX-12 is 5% ,Iap of the propellant is lower about 0. 458% compared with basic formulation. With the increasing of FOX-12 content,the burning rate of propellants decreases at the same pressure, and the friction sensitivity, impact sensitivity and electrostatic spark sensitivity of propellants reduce gradually. When the content of FOX-12 is 5% ,the maximum decline of burning rate is 4.75% at 4 ~ 10 Mpa,but the friction sensitivity of the propellant reduces from 96% to 68%. Because the vacuum stability of FOX-12 is lower than that of AP, the thermal stability of propellant with FOX-12 decreases accordingly, but meets the application requirements. The negative oxygen balance of FOX-12 may reduce the reaction rate

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

    CSIR Research Space (South Africa)

    Van Leeuwen, TT

    2014-01-01

    Full Text Available 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...

  17. Simplified Burn-Rate Model for CMDB Propellants

    OpenAIRE

    Kulkarni, A. R.; Bhat, V.K.; S. P. Phadke; R.G.K. Nair

    1990-01-01

    A single model has been proposed to predict the burning rates of bimodal AP,RDX and aluminum containing CMDB propellants. This is done in terms of the respective physical constants on the basis of a recently developed model of combustion of CMDB propellants. The study has been carried out to examine the effects of changes in propellants composition, AP particle size and pressures on burning rate. Computer programs were developed for this purpose and the results obtained for typical set...

  18. Application of transient burning rate model of solid propellant in electrothermal-chemical launch simulation

    Directory of Open Access Journals (Sweden)

    Yan-jie Ni

    2016-04-01

    Full Text Available A 30 mm electrothermal-chemical (ETC gun experimental system is employed to research the burning rate characteristics of 4/7 high-nitrogen solid propellant. Enhanced gas generation rates (EGGR of propellants during and after electrical discharges are verified in the experiments. A modified 0D internal ballistic model is established to simulate the ETC launch. According to the measured pressure and electrical parameters, a transient burning rate law including the influence of EGGR coefficient by electric power and pressure gradient (dp/dt is added into the model. The EGGR coefficient of 4/7 high-nitrogen solid propellant is equal to 0.005 MW−1. Both simulated breech pressure and projectile muzzle velocity accord with the experimental results well. Compared with Woodley's modified burning rate law, the breech pressure curves acquired by the transient burning rate law are more consistent with test results. Based on the parameters calculated in the model, the relationship among propellant burning rate, pressure gradient (dp/dt and electric power is analyzed. Depending on the transient burning rate law and experimental data, the burning of solid propellant under the condition of plasma is described more accurately.

  19. Application of transient burning rate model of solid propellant in electrothermal-chemical launch simulation

    Institute of Scientific and Technical Information of China (English)

    Yan-jie NI; Yong JIN; Gang WAN; Chun-xia YANG; Hai-yuan LI; Bao-ming LI

    2016-01-01

    A 30 mm electrothermal-chemical (ETC) gun experimental system is employed to research the burning rate characteristics of 4/7 high-nitrogen solid propellant. Enhanced gas generation rates (EGGR) of propellants during and after electrical discharges are verified in the experiments. A modified 0D internal ballistic model is established to simulate the ETC launch. According to the measured pressure and electrical parameters, a transient burning rate law including the influence of EGGR coefficient by electric power and pressure gradient (dp/dt) is added into the model. The EGGR coefficient of 4/7 high-nitrogen solid propellant is equal to 0.005 MW−1. Both simulated breech pressure and projectile muzzle velocity accord with the experimental results well. Compared with Woodley’s modified burning rate law, the breech pressure curves acquired by the transient burning rate law are more consistent with test results. Based on the parameters calculated in the model, the relationship among propellant burning rate, pressure gradient (dp/dt) and electric power is analyzed. Depending on the transient burning rate law and experimental data, the burning of solid propellant under the condition of plasma is described more accurately.

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

    Science.gov (United States)

    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

  1. Magnetogasdynamic Control of Burning Rate of Condensed System

    Directory of Open Access Journals (Sweden)

    I. G. Borovskoy

    1995-01-01

    Full Text Available Presents the results of modelling combustion products of solid propellant flow. The product of combustion is the ionized gas occurring in a channel with current conducting walls, when a part of the channel is in the external homogeneous magnetic field, oriented in such a way that the ponderomotive force, occuring in the flow region, is opposite to the flow. This results in gas deceleration and increase of static pressure. For the condenensed systems, whose mass burning rate is in direct proportion to the environment pressure, the static pressure increase causes increase of mass burning rate. The basic parameters have been determined by numerical simulation. The nature of their influence on the process of combustion in a cylindrical channel has also been determined. The study revealed that a ten-fold increase of burning rate is possible at moderate values of the parameter of magnetogasdynamic interaction.

  2. Simplified Burn-Rate Model for CMDB Propellants

    Directory of Open Access Journals (Sweden)

    A. R. Kulkarni

    1990-07-01

    Full Text Available A single model has been proposed to predict the burning rates of bimodal AP,RDX and aluminum containing CMDB propellants. This is done in terms of the respective physical constants on the basis of a recently developed model of combustion of CMDB propellants. The study has been carried out to examine the effects of changes in propellants composition, AP particle size and pressures on burning rate. Computer programs were developed for this purpose and the results obtained for typical sets of input data have been presented and compared with the actual results.

  3. A model for the burning rates of composite propellants

    Science.gov (United States)

    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.

  4. Rill erosion rates in burned forests

    Science.gov (United States)

    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...

  5. Mortality rate associated with hospital acquired infections among burn patients

    Directory of Open Access Journals (Sweden)

    Saima Aslam Bharwana

    2016-09-01

    Full Text Available Hospital acquired infections (HAIs are the major contributors of mortality associated with burn injuries. The aim of this research was to document the antecedents affiliated with major burn injuries, hospitalization and mortality in burn patients. We performed a single center prospective study of patients admitted during 3 months period (April-June 2014 in burn wards of government hospital. There were 100 patients in this investigation which were observed weekly. The inclusion criterion was based on the shifting of patients from emergency to the wards after initial treatment of more than 24 h. Variables included were age and gender of the patient, the percent total body surface area (%TBSA burn, the cause of the burn. Mean age of patients was 30.29 years. More females (55.67% were admitted than males (44.32%. The total body surface area (%TBSA burnt were from 15%- 95% respectively moreover children were more sensitive to hospital acquired infections (HAIs and mortality rate was 34% in children with mean age of 5 years and disability of body parts were 42% among 75% were females. Whereas the most common (HAIs were primary blood stream (PBS with mean value of 30.50, wound infections (WIS were at second prevalence with mean value of 27.50, followed by sepsis (S and pneumonia (P 10.33, eye infections (EIs 4.833 and urinary tract infections (UTIs 2.667. Factors significantly (p-value= 0.000 associated with increased duration of hospitalization caught HAIs mortality include the age and gender of the patient, the cause of burn, inhalation injury, the region affected and %TBSA burnt. It concluded that the mortality was very much dependent on age and gender of the patient, burn causes, affected area as well as %TBSA burnt are considerable factors in determining the relationship of HAIs and whether the patients will survive or knuckle to injuries. Better compliance techniques, stricter control over disinfection and sterilization practices and usage of

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

    Directory of Open Access Journals (Sweden)

    T. T. van Leeuwen

    2014-06-01

    Full Text Available 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.

  7. Fuel Burning Rate Model for Stratified Charge Engine

    Institute of Scientific and Technical Information of China (English)

    SONG Jin'ou; JIANG Zejun; YAO Chunde; WANG Hongfu

    2006-01-01

    A zero-dimensional single-zone double-curve model is presented to predict fuel burning rate in stratified charge engines, and it is integrated with GT-Power to predict the overall performance of the stratified charge engines.The model consists of two exponential functions for calculating the fuel burning rate in different charge zones.The model factors are determined by a non-linear curve fitting technique, based on the experimental data obtained from 30 cases in middle and low loads.The results show good agreement between the measured and calculated cylinder pressures,and the deviation between calculated and measured cylinder pressures is less than 5%.The zerodimensional single-zone double-curve model is successful in the combustion modeling for stratified charge engines.

  8. The Research on Transient Burning Rate of Solid Propellant by Digital Image Processing

    Directory of Open Access Journals (Sweden)

    Xin Peng

    2016-01-01

    Full Text Available In order to obtain the burn rate of the solid propellant that is the important parameter of transient burning, the new method named digital image processing is presented. In the article , the principle of digital image processing is analysed; The burning face of the sample in the each time is located according the image and the coordinates of the burning face is obtained. In experiment the transient burn rate is measured by digital image processing and the accuracy is acceptable.

  9. Effects of the acceleration vector on transient burning rate of an aluminized solid propellant.

    Science.gov (United States)

    Northam, G. B.

    1971-01-01

    Experimental results concerning the transient burning-rate augmentation of a 16% aluminum polybutadiene acrylic acid (PBAA) propellant burned in a 2-in. web motor at pressure levels from 300 to 1200 psia with centrifugal accelerations from 0 to 140 g. The orientation of the acceleration vector was varied to determine its effect on the transient burning rate. The burning-rate augmentation was strongly dependent on (1) acceleration level, (2) propellant distance burned (or burn time), and (3) orientation of the acceleration vector with respect to the burning surface. This transient rate augmentation resulted from the retention of molten metallic residue on the burning surface by the normal acceleration loading. The presence of the residue altered the combustion zone heat transfer and caused increased localized burning rates, as evidenced by the pitted propellant surfaces that were observed from extinction tests conducted at various acceleration levels.

  10. Burning high-level TRU waste in fusion fission reactors

    Science.gov (United States)

    Shen, Yaosong

    2016-09-01

    Recently, the concept of actinide burning instead of a once-through fuel cycle for disposing spent nuclear fuel seems to get much more attention. A new method of burning high-level transuranic (TRU) waste combined with Thorium-Uranium (Th-U) fuel in the subcritical reactors driven by external fusion neutron sources is proposed in this paper. The thorium-based TRU fuel burns all of the long-lived actinides via a hard neutron spectrum while outputting power. A one-dimensional model of the reactor concept was built by means of the ONESN_BURN code with new data libraries. The numerical results included actinide radioactivity, biological hazard potential, and much higher burnup rate of high-level transuranic waste. The comparison of the fusion-fission reactor with the thermal reactor shows that the harder neutron spectrum is more efficient than the soft. The Th-U cycle produces less TRU, less radiotoxicity and fewer long-lived actinides. The Th-U cycle provides breeding of 233U with a long operation time (>20 years), hence significantly reducing the reactivity swing while improving safety and burnup.

  11. Helium Burning Reaction Rate Uncertainties and Consequences for Supernovae

    Science.gov (United States)

    Tur, C.; Heger, A.; Austin, S. M.

    2007-10-01

    The triple alpha and ^12C(,)^16O reaction rates determine the carbon to oxygen ratio at the completion of core helium burning in stars, which, in turn, influences the later stellar burning stages. We explored the dependence of massive star evolution and nucleosynthesis yields on the experimental uncertainties in the triple alpha rate (10 to 12%) and the ^12C(,)^16O rate (25 to 35%) using full stellar models followed to core collapse and including supernova explosion. The production factors of medium-weight elements obtained by using the Lodders (2003) solar abundances for the initial star composition, rather than the abundances of Anders & Grevesse (1989), provide a less stringent constraint on the ^12C(,)^16O rate. Variations within the current uncertainties in both reaction rates, however, induce significant changes in the central carbon abundance at core carbon ignition and in the mass of the supernova remnant. An experiment is being carried out by an NSCL/WMU collaboration to improve the accuracy of the triple alpha reaction rate.

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

    Science.gov (United States)

    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.

  13. Experimental study on composite solid propellant material burning rate using algorithm MATLAB

    Directory of Open Access Journals (Sweden)

    Thunaipragasam Selvakumaran

    2016-01-01

    Full Text Available In rocketry application, now-a-days instead of monopropellants slowly composite propellants are introduced. Burning rate of a solid state composite propellant depends on many factors like oxidizer-binder ratio, oxidizer particle size and distribution, particle size and its distribution, pressure, temperature, etc. Several researchers had taken the mass varied composite propellant. In that, the ammonium perchlorate mainly varied from 85 to 90%. This paper deals with the oxidizer rich propellant by allowing small variation of fuel cum binder ranging from 2%, 4%, 6%, and 8% by mass. Since the percent of the binder is very less compared to the oxidizer, the mixture remains in a powder form. The powder samples are used to make a pressed pellet. Experiments were conducted in closed window bomb set-up at pressures of 2, 3.5, and 7 MN/m2. The burning rates are calculated from the combustion photography (images taken by a high-speed camera. These images were processed frame by frame in MATLAB, detecting the edges in the images of the frames. The burning rate is obtained as the slope of the linear fit from MATLAB and observed that the burn rate increases with the mass variation of constituents present in solid state composite propellant. The result indicates a remarkable increase in burn rate of 26.66%, 20%, 16.66%, and 3.33% for Mix 1, 2, 3, 4 compared with Mix 5 at 7 MN/m2. The percentage variations in burn rate between Mix 1 and Mix 5 at 2, 3.5, and 7 MN/m2 are 25.833%, 32.322%, and 26.185%, respectively.

  14. Burns

    Science.gov (United States)

    A burn is damage to your body's tissues caused by heat, chemicals, electricity, sunlight, or radiation. Scalds from hot ... and gases are the most common causes of burns. Another kind is an inhalation injury, caused by ...

  15. Quantitative assessments of burn degree by high-frequency ultrasonic backscattering and statistical model

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Yi-Hsun; Wang, Shyh-Hau [Department of Computer Science and Information Engineering, and Institute of Medical Informatics, National Cheng Kung University, No 1, University Road, Tainan City 70101, Taiwan (China); Huang, Chih-Chung, E-mail: shyhhau@mail.ncku.edu.tw [Department of Electrical Engineering, Fu Jen Catholic University, 510, Chung Cheng Rd, Hsin Chuang, Taipei County 24205, Taiwan (China)

    2011-02-07

    An accurate and quantitative modality to assess the burn degree is crucial for determining further treatments to be properly applied to burn injury patients. Ultrasounds with frequencies higher than 20 MHz have been applied to dermatological diagnosis due to its high resolution and noninvasive capability. Yet, it is still lacking a substantial means to sensitively correlate the burn degree and ultrasonic measurements quantitatively. Thus, a 50 MHz ultrasound system was developed and implemented to measure ultrasonic signals backscattered from the burned skin tissues. Various burn degrees were achieved by placing a 100 deg. C brass plate onto the dorsal skins of anesthetized rats for various durations ranged from 5 to 20 s. The burn degrees were correlated with ultrasonic parameters, including integrated backscatter (IB) and Nakagami parameter (m) calculated from ultrasonic signals acquired from the burned tissues of a 5 x 1.4 mm (width x depth) area. Results demonstrated that both IB and m decreased exponentially with the increase of burn degree. Specifically, an IB of -79.0 {+-} 2.4 (mean {+-} standard deviation) dB for normal skin tissues tended to decrease to -94.0 {+-} 1.3 dB for those burned for 20 s, while the corresponding Nakagami parameters tended to decrease from 0.76 {+-} 0.08 to 0.45 {+-} 0.04. The variation of both IB and m was partially associated with the change of properties of collagen fibers from the burned tissues verified by samples of tissue histological sections. Particularly, the m parameter may be more sensitive to differentiate burned skin due to the fact that it has a greater rate of change with respect to different burn durations. These ultrasonic parameters in conjunction with high-frequency B-mode and Nakagami images could have the potential to assess the burn degree quantitatively.

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

    Directory of Open Access Journals (Sweden)

    G. R. van der Werf

    2012-08-01

    in Africa which 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.

  17. Effect of burn-up and high burn-up structure on spent nuclear fuel alteration

    Energy Technology Data Exchange (ETDEWEB)

    Clarens, F.; Gonzalez-Robles, E.; Gimenez, F. J.; Casas, I.; Pablo, J. de; Serrano, D.; Wegen, D.; Glatz, J. P.; Martinez-Esparza, A.

    2009-07-01

    In this report the results of the experimental work carried out within the collaboration project between ITU-ENRESA-UPC/CTM on spent fuel (SF) covering the period 2005-2007 were presented. Studies on both RN release (Fast Release Fraction and matrix dissolution rate) and secondary phase formation were carried out by static and flow through experiments. Experiments were focussed on the study of the effect of BU with two PWR SF irradiated in commercial reactors with mean burn-ups of 48 and 60 MWd/KgU and; the effect of High Burn-up Structure (HBS) using powdered samples prepared from different radial positions. Additionally, two synthetic leaching solutions, bicarbonate and granitic bentonite ground wa ter were used. Higher releases were determined for RN from SF samples prepared from the center in comparison with the fuel from the periphery. However, within the studied range, no BU effect was observed. After one year of contact time, secondary phases were observed in batch experiments, covering the SF surface. Part of the work was performed for the Project NF-PRO of the European Commission 6th Framework Programme under contract no 2389. (Author)

  18. Selection of burning rate modifiers for hydrazinium nitroformate

    NARCIS (Netherlands)

    Tummers, M.J.; Heijden, A.E.D.M. van der; Veen, E.H. van

    2012-01-01

    Species including N2H4, NH3 and N2O are known to be present near the surface of burning hydrazinium nitroformate (HNF). In this paper, planar laser induced fluorescence from the near surface region of burning HNF pellets is reported indicating the presence of NO2. These four species are formed in th

  19. Burns

    Science.gov (United States)

    To help prevent burns: Install smoke alarms in your home. Check and change batteries regularly. Teach children about fire safety and the danger of matches and fireworks. Keep children from climbing on top of a stove ...

  20. Hydrocolloid dressing in pediatric burns may decrease operative intervention rates.

    LENUS (Irish Health Repository)

    Martin, Fiachra T

    2010-03-01

    Partial-thickness scalds are the most common pediatric burn injury, and primary management consists of wound dressings to optimize the environment for reepithelialization. Operative intervention is reserved for burns that fail to heal using conservative methods. Worldwide, paraffin-based gauze (Jelonet) is the most common burn dressing; but literature suggests that it adheres to wounds and requires more frequent dressing change that may traumatize newly epithelialized surfaces. Hydrocolloid dressings (DuoDERM) provide an occlusive moist environment to optimize healing and are associated with less frequent dressing changes.

  1. Application of Closed Vessel Technique for the Evaluation of Burning Rates of Propellants at Low Pressures

    Directory of Open Access Journals (Sweden)

    D. Vittal

    1977-04-01

    Full Text Available Closed vessel technique has been well established for the evaluation of burning characteristics of gun, mortar and small arms propellants at high pressures of about 750 kg/cm/sup 2/ - 3000 kg/cm/sup 2/ propellants in the pressure range up to about 200 kg/cm/sup 2/ (19.6 MPa. One of the modern trends in armaments technology is development of short range, high efficiency rockets and rocket assisted projectiles where the chamber pressure are in the range of 100 kg/cm/sup 2/ - 800 kg/cm/sup 2/ (9.8 MPa-78.5 MPa. An extension of the closed vessel technique is now presented for the measurement of rates of burning of propellants in this pressure range and a few experimental results on some conventional propellants are given.

  2. Burning high-level TRU waste in fusion fission reactors

    National Research Council Canada - National Science Library

    Shen, Yaosong

    2016-01-01

    .... A new method of burning high-level transuranic (TRU) waste combined with Thorium–Uranium (Th–U) fuel in the subcritical reactors driven by external fusion neutron sources is proposed in this paper...

  3. High-tension Electrical Burns: Report of Two Cases

    OpenAIRE

    Abbas, A.D.; Dabkana, T.M.; Tahir, C.; Naaya, H.U.

    2009-01-01

    High-tension electrical burns are a rare but devastating form of injury. The objective of this case report is to bring to the fore the severity of this rare form of injury and highlight the benefits of active surgical management of such a condition. We report the cases of two patients who were managed for high-tension electrical burns and highlight the main features of their presentation and management. Both patients needed urgent resuscitation and subsequent multiple amputations and disartic...

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

    Science.gov (United States)

    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 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%).

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

    Science.gov (United States)

    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.

  6. Explicit expression to predict the erosive burning rate of solid propellants

    Science.gov (United States)

    Wang, S.

    1986-01-01

    Using the theory of gas dynamics and heat transfer from a turbulent gas flow to the burning surface of propellant along a permeable wall, an explicit expression is derived to predict the burning rate of the solid propellant with crossflow. Results of the calculation have been compared with experimental data and proved to be correct.

  7. Burn Rate Modelling of Solid Rocket Propellants (Short Communication

    Directory of Open Access Journals (Sweden)

    A.R. Kulkarni

    1998-01-01

    Full Text Available A generalised model of burning of a solid rocket propellant based on kinetics of propellant hasbeen developed. A complete set of variables has been formed after examining the existing models.Buckingham theorem provides the functional form of the model, such that the existing models are thesubcases of this generalised model. This proposed model has been validated by an experimental data.

  8. Burn Rate Studies on AN-Based Propellants: Effect of N-N Bonded Binders.

    Directory of Open Access Journals (Sweden)

    C. Oommen

    1996-12-01

    Full Text Available New epoxy resins having N-N bonds in their structures have been employed as binders for ammonium nitrate (AN-based propellants. The resins have been characterized by various analytical techniques. The effect of the new binders on the burn rates of AN-based compositions including the metallized systems has been examined. The overall enhancement in the burn rate, as compared to that observed with conventional binders, has been explained in terms of the combustion reactivity of the N-N bondwiththe oxidizing speciesproduced duringcombustion. Furtherincreasein burn rate canbe achieved by inclusion of magnesium metal or ammonium perchlorate into these compositions.

  9. Transient Burning Rate Model for Solid Rocket Motor Internal Ballistic Simulations

    Directory of Open Access Journals (Sweden)

    David R. Greatrix

    2008-01-01

    Full Text Available A general numerical model based on the Zeldovich-Novozhilov solid-phase energy conservation result for unsteady solid-propellant burning is presented in this paper. Unlike past models, the integrated temperature distribution in the solid phase is utilized directly for estimating instantaneous burning rate (rather than the thermal gradient at the burning surface. The burning model is general in the sense that the model may be incorporated for various propellant burning-rate mechanisms. Given the availability of pressure-related experimental data in the open literature, varying static pressure is the principal mechanism of interest in this study. The example predicted results presented in this paper are to a substantial extent consistent with the corresponding experimental firing response data.

  10. The Use of Fractal for Prediction of Burning Rate of Composite Solid Propellants

    Institute of Scientific and Technical Information of China (English)

    ManouchehrNikazar; MohammadB.Bagherpour; 等

    2000-01-01

    By using fractal geometry is is possible to calculate the actual AP(Ammonium Perchlorate)surface area and oxidizer-binder interface fractal dimension in the prediction of burning rate of commposite solid propellants.In this investigation,the fractal dimension was determined by a procedure known as the "Box counting Method".using this dimensio,surface area relations were developed for the rough particles.This method was implemented in the PEM(Petite Ensemble Model) burning rate model,The comparison of burning rates for a typical propellant by the PEM and fractal model shows that the burning rates botained by using the fractal geometry are slightly less than those obtained by the PEM model.

  11. Application of Ultrasonic Technique for Measurement of Instantaneous Burn Rate of Solid Propellants .

    Directory of Open Access Journals (Sweden)

    Desh Deepak

    1998-04-01

    Full Text Available The ultrasonic pulse-echo technique has been applied for the measurement of instantaneous burnrate of aluminised composite solid propellants. The tests have been carried out on end-burning 30 mmthick propellant specimens at nearly constant pressure of about 1.9 MPa. Necessary software forpost-test data processing and instantaneous burn rate computations have been developed. The burnrates measured by the ultrasonic technique have been compared with those obtained from ballisticevaluation motor tests on propellant from the same mix. An accuracy of about +- 1 per cent ininstantaneous burn rate measurements and reproducibility of results have been demonstrated byapplying ultrasonic technique.

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

    Science.gov (United States)

    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.

  13. Performance evaluation of commercial copper chromites as burning rate catalyst for solid propellants

    Directory of Open Access Journals (Sweden)

    Milton Faria Diniz

    2010-09-01

    Full Text Available Copper chromites are well known as burning rate catalysts for the combustion of composite solid propellants, used as a source of energy for rocket propulsion. The propellant burning rate depends upon the catalyst characteristics such as chemical composition and specific surface area. In this work, copper chromite samples from different suppliers were characterized by chemical analysis, FT-IR spectroscopy and by surface area measurement (BET. The samples were then evaluated as burning rate catalyst in a typical composite propellant formulation based on HTPB binder, ammonium perchlorate and aluminum. The obtained surface area values are very close to those informed by the catalyst suppliers. The propellant processing as well as its mechanical properties were not substantially affected by the type of catalyst. Some copper chromite catalysts caused an increase in the propellant burning rate in comparison to the iron oxide catalyst. The results show that in addition to the surface area, other parameters like chemical composition, crystalline structure and the presence of impurities might be affecting the catalyst performance. All evaluated copper chromite samples may be used as burning rate catalyst in composite solid propellant formulations, with slight advantages for the SX14, Cu-0202P and Cu-1800P samples, which led to the highest burning rate propellants.

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

    Science.gov (United States)

    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.

  15. The direct effects of strain on burning rates of composite solid propellants

    Science.gov (United States)

    Langhenry, M. T.

    1984-01-01

    A mathematical model is developed to predict burn rate augmentation due to strain in a composite solid propellant. The model assumes the effect is due to the ability of the flame to penetrate the small fissures and voids that form when a propellant is strained. The number and size of these fissures is obtained by applying a flaw propagation analysis to randomly distributed flaws that form when the binder-oxidizer particle bonds break under stress. A flame height is calculated with Summerfield's burn rate equation and is used to compute the burn rate augmentation based upon the additional burn area created when the flame penetrates the fissures. Comparisons are made with data obtained from published sources. The existence of threshold pressure and strains, above which augmentation occurs, is verified although the model predicts a lower threshold pressure and higher threshold strain than expected. Further results and applications of the model are discussed.

  16. Studies on Composite Extrudable Propellant with varied Burning Rate Pressure Index 'n'

    Directory of Open Access Journals (Sweden)

    T. L. Varghese

    1989-01-01

    Full Text Available This paper discusses the development of composite propellantextrusion technique and the study of burning rate pressure indices nwith respect to compositional variations. The n is found to vary from0.35 to plateau and plateau to mesa by suitable compositionalmodifications. Compositional influence on burning rate with specificreference to plateau and mesaburning additives is described. Detailsof the process parameters like fluidity of the slurry, extrusion pressure,extrusion rate and die-swell are presented. This propellant is based onISRO-CTPB binder using ISRO-AP as oxidizer. Ammonium perchlorate (AP particle size variation and inclusion of additives likePVC, lead stearate, ammonium sulphate, lithium fluoride etc. are foundto influence the burning rate pressure index n.

  17. Effects of oblique air flow on burning rates of square ethanol pool fires.

    Science.gov (United States)

    Tao, Changfa; He, Yaping; Li, Yuan; Wang, Xishi

    2013-09-15

    The effects of downward airflow on the burning rate and/or burning intensity of square alcohol pool fires for different airflow speeds and directions have been studied experimentally in an inclined wind tunnel. An interesting flame-wrapping phenomenon, caused by impingement of air flow, was observed. The mass burning intensity was found to increase with the airflow speed and the impinging angle. The fuel pan rim temperatures were also measured to study the effect of wind direction and speed on heat transfer from the flame to the fuel source. A model based on heat transfer analysis was developed to correlate the burning intensity with the pan rim characteristic temperature. A good correlation was established between the model results and the experimental results.

  18. Effect of Oxidizer Particle Size on Burning Rate and Thermal Decomposition of Composite Solid Propellants

    Directory of Open Access Journals (Sweden)

    K. Kishore

    1982-07-01

    Full Text Available Studies on Thermal decomposition of ammonium perchlorarte(AP- polystyrene(PS propellant and burning rate of PS/AP propellant have been carried out as a function of oxidizer particle size. Thermal decomposition of AP and AP/PS propellant as function of AP particle size shows a maximum rate around 100 micro particle size which has been explained on the basis of Mample's theory. No such maximum is observed in the case of PS/AP propellant burning rate.

  19. High Impetus Cool Burning Gun Propellants

    Directory of Open Access Journals (Sweden)

    R.S. Dames

    2000-07-01

    Full Text Available This study explores the possibility of reducing the flame temperature (Tf without decrease in impetus of RDX-NC matrix-based high energy gun propellants by partial replacement of RDX with triaminoguanidine nitrate (TAGN. Compositions containing TAGN as an energetic oxidiser with varying percentage of RDX have been formulated. Glycidyl azide polymer was incorporated as an energetic plasticiser to achieve the higher level of impetus. Performance in terms of ballistic parameters (theoretical/experimental sensitivity, thermal characteristics, stability and mechanical properties was evaluated and compared with the basic composition containing RDX as a single oxidiser. Experimental data indicates that the partial replacement of RDX by TAGN in gun propellant compositions decreases Tf significantly with only marginal decrease in impetus. "

  20. Shell and explosive hydrogen burning. Nuclear reaction rates for hydrogen burning in RGB, AGB and Novae

    Energy Technology Data Exchange (ETDEWEB)

    Boeltzig, A. [Gran Sasso Science Institute, L' Aquila (Italy); Bruno, C.G.; Davinson, T. [University of Edinburgh, SUPA, School of Physics and Astronomy, Edinburgh (United Kingdom); Cavanna, F.; Ferraro, F. [Dipartimento di Fisica, Universita di Genova (Italy); INFN, Genova (Italy); Cristallo, S. [Osservatorio Astronomico di Collurania, INAF, Teramo (Italy); INFN, Napoli (Italy); Depalo, R. [Dipartimento di Fisica e Astronomia, Universita di Padova, Padova (Italy); INFN, Padova (Italy); DeBoer, R.J.; Wiescher, M. [University of Notre Dame, Institute for Structure and Nuclear Astrophysics, Joint Institute for Nuclear Astrophysics, Notre Dame, Indiana (United States); Di Leva, A.; Imbriani, G. [Dipartimento di Fisica, Universita di Napoli Federico II, Napoli (Italy); INFN, Napoli (Italy); Marigo, P. [Dipartimento di Fisica e Astronomia, Universita di Padova, Padova (Italy); Terrasi, F. [Dipartimento di Matematica e Fisica Seconda Universita di Napoli, Caserta (Italy); INFN, Napoli (Italy)

    2016-04-15

    The nucleosynthesis of light elements, from helium up to silicon, mainly occurs in Red Giant and Asymptotic Giant Branch stars and Novae. The relative abundances of the synthesized nuclides critically depend on the rates of the nuclear processes involved, often through non-trivial reaction chains, combined with complex mixing mechanisms. In this paper, we summarize the contributions made by LUNA experiments in furthering our understanding of nuclear reaction rates necessary for modeling nucleosynthesis in AGB stars and Novae explosions. (orig.)

  1. Application of Al Powder on High Burning-rate AP/CMDB Propellants%Al 粉在高燃速 AP/CMDB 推进剂中的应用

    Institute of Scientific and Technical Information of China (English)

    邓重清; 蔚红建; 张正中

    2015-01-01

    The heat of combustion,combustion performance and thermal decomposition characteristics of AP/CMDB propellants containing Al powder with different granularity and content were researched by using calorimeter, burning rate measurement and PDSC,respectively.The results indicate that the heat of detonation is proportional to the content of Al powder.The Al powder content in the rang of 0 - 8% (mass fraction)has less effect on the combustion performance of propellants.As the granularity of Al powder decreases from 14μm to 5μm,the heat of combustion decreases by 40J/g and the heat of exothermic decomposition increases by 107J/g,the burning rates in the pressure range of 7 - 10 MPa increase by 1 - 1.8 mm/s and the pressure exponent in the pressure range of 7-22 MPa decreases from 0.56 to 0.50.As the granularity of Al powder (mass fraction of 3% )decreases to 150nm,the heat of detonation decreases by 93 J/g and the heat of exothermic decomposition increases by 343 J/g,the burning rates in the pressure rang of 18-22 MPa increase by 2-3 mm/s.%采用量热仪、燃速仪、PDSC 分别研究了含不同粒度和含量 Al 粉的高燃速 AP/CMDB 推进剂的爆热、燃烧性能与热分解特性。结果表明,推进剂爆热与 Al 粉的含量成正比;Al 粉质量分数为0~8%时,对推进剂燃烧性能无明显影响;Al 粉粒度由14μm 减小至5μm 时,推进剂爆热降低40 J/g,热分解放热量增加107 J/g,7~10 MPa 压强下推进剂燃速提高1~1.8 mm/s,7~22 MPa 下压强指数由0.56降至0.50;当 Al 粉(质量分数3%)粒度减小为150 nm 时,推进剂的爆热降低93 J/g,热分解放热量增加343 J/g,18~22 MPa 压强下的燃速提高2~3 mm/s。

  2. Burn Rate Studies of a Titanium-Based Ptrotechnic Smoke Composition

    Directory of Open Access Journals (Sweden)

    A. G. Rajendran

    2000-04-01

    Full Text Available A pyrotechnic smoke composition producing titanium tetrachloride (TiCl4 as one of the major reaciion products hasj been studied. The composition consists of titanium metal powder, hexachloroethae (C2CI6, potassium perchlorate (KCIO4 and titanium dioxide (TiO2/zinc oxide (ZnO. PyrotFcHnic aluminium was added. in small percentages to tailor the burn rate. The effect of percentage variation of KClO4. TiO21 ZnO. titanium and aluminium on the burn rate has beeninvestigated. While, the burn rate decreases as the percentage of TiO2/ZnO increases, it reaches a maximum as the percentage of KCIO4 is successively increased, but falls off on further increase. Thismaximum has been first fixbd by studying the tricomponent system containing no oxide. It corresponds td 25 per cent KClO4. Successive additions of C2Cl6 and ZnO in 1 :3 mol ratio or C2Cl6and TiO2 in 2:3 mol ratio lead to cooler compositions that burn smoothly without much flame and at lower temperatures. (Compositions containing less than 5 per cent titanium is difficult to ignite. Similarly, addition of excess titanium or small quantities of alljminium to the composition is found to increase the burn rate.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    G. R. van der Werf

    2013-01-01

    current situation; 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.

  5. High explosive programmed burn in the FLAG code

    Energy Technology Data Exchange (ETDEWEB)

    Mandell, D.; Burton, D.; Lund, C.

    1998-02-01

    The models used to calculate the programmed burn high-explosive lighting times for two- and three-dimensions in the FLAG code are described. FLAG uses an unstructured polyhedra grid. The calculations were compared to exact solutions for a square in two dimensions and for a cube in three dimensions. The maximum error was 3.95 percent in two dimensions and 4.84 percent in three dimensions. The high explosive lighting time model described has the advantage that only one cell at a time needs to be considered.

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

    Directory of Open Access Journals (Sweden)

    Mohammad Javad Fatemi

    2013-01-01

    Full Text Available 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.

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

    Science.gov (United States)

    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

  8. Effect of Loading Densities in Closed Vessel Tests on the Burning Rate of a Propelling Charge

    Directory of Open Access Journals (Sweden)

    Pragati Mehta

    2015-04-01

    Full Text Available Closed vessel firing of gun propellant at different loading densities is conducted for evaluation of its ballistic parameters. Although in actual gun applications, loading densities are higher, but for closed vessel evaluation standard loading density is taken as 0.2 g/cc for interior ballistic calculations of guns. Closed vessel evaluation of standard triple-base propellant in hepta-tubular configuration with loading density varying in the range of 0.2 g/cc to 0.3 g/cc is conducted for the evaluation of salient ballistic parameters. It is observed that maximum pressure increases with increase in loading density of propellants. As loading density increases, rate of rise of pressure also increases. Accordingly, a rise in burning rate is also observed. However, the burning rate index (α and coefficient (β of the power law of burning (r = βPα is found independent of loading density. The average values of these burning rate parameters are calculated as (α = 0.78 and (β = 0.45 for the studied propellant.Defence Science Journal, Vol. 65, No. 2, March 2015, pp.126-130, DOI:http://dx.doi.org/10.14429/dsj.65.8158

  9. High-voltage electrical burns due to copper theft - Case series.

    Science.gov (United States)

    Braga, M J; Oliveira, I; Egipto, P; Silva, A

    2016-03-31

    Electrical burns are among the most devastating trauma inflicted on the human body. These burns have a higher morbidity, length of stay and a much higher risk of amputation than any other type of burn. Electrical burns affect mostly young, working males because they are more frequently the result of a work accident. However, possibly due to the worldwide economic crisis, we are experiencing a new phenomenon: the theft of high-voltage copper wiring.

  10. High-voltage electrical burns due to copper theft – Case series

    Science.gov (United States)

    Braga, M.J.; Oliveira, I.; Egipto, P.; Silva, A.

    2016-01-01

    Summary Electrical burns are among the most devastating trauma inflicted on the human body. These burns have a higher morbidity, length of stay and a much higher risk of amputation than any other type of burn. Electrical burns affect mostly young, working males because they are more frequently the result of a work accident. However, possibly due to the worldwide economic crisis, we are experiencing a new phenomenon: the theft of high-voltage copper wiring. PMID:27857650

  11. Thermodynamic analysis for high burn-up fuel internal chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Fuji, Kensho; Kyoh, Bunkei [Kinki Univ., Higashi-Osaka, Osaka (Japan). Faculty of Science and Technology

    1997-09-01

    Chemical states of fission products and actinide elements in high burn-up LWR fuel pellets have been analyzed thermodynamically using the computer program SOLGASMIX-PV. Calculations with this computer code have been performed for a complex multi-component system, which comprises 54 chemical species. The analysis shows that neither alkali nor alkaline-earth uranates are formed, but alkali and alkaline-earth molybdates exist in irradiated LWR fuel pellets in contrast with their post irradiation examinations. These molybdates tend to increase with increasing oxygen potential in the fuel under operating conditions, whereas the zirconates decrease. (author)

  12. Non-explosive hydrogen and helium burnings: abundance predictions from the NACRE reaction rate compilation

    Science.gov (United States)

    Arnould, M.; Goriely, S.; Jorissen, A.

    1999-07-01

    The abundances of the isotopes of the elements from C to Al produced by the non-explosive CNO, NeNa and MgAl modes of hydrogen burning, as well as by helium burning, are calculated with the thermonuclear rates recommended by the European compilation of reaction rates for astrophysics (NACRE). The impact of nuclear physics uncertainties on the derived abundances is discussed in the framework of a simple parametric astrophysical model. These calculations have the virtue of being a guide in the selection of the nuclear uncertainties that have to be duly analyzed in detailed model stars, particularly in order to perform meaningful confrontations between abundance observations and predictions. They are also hoped to help nuclear astrophysicists pinpointing the rate uncertainties that have to be reduced most urgently. An electronic version of this paper, with colour figures, is available at {\\it http://astro.ulb.ac.be}

  13. High pressure droplet burning experiments in reduced gravity

    Science.gov (United States)

    Chauveau, Christian; Goekalp, Iskender

    1995-01-01

    A parametric investigation of single droplet gasification regimes is helpful in providing the necessary physical ideas for sub-grid models used in spray combustion numerical prediction codes. A research program has been initiated at the LCSR to explore the vaporization regimes of single and interacting hydrocarbon and liquid oxygen droplets under high pressure conditions. This paper summarizes the status of the LCSR program on the high pressure burning of single fuel droplets; recent results obtained under normal and reduced gravity conditions with suspended droplets are presented. In the work described here, parabolic flights of the CNES Caravelle is used to create a reduced gravity environment of the order of 10(exp -2) g(sub O). For all the droplet burning experiments reported here, the suspended droplet initial diameters are scattered around 1.5 mm; and the ambient air temperature is 300 K. The ambient pressure is varied between 0.1 MPa and 12 MPa. Four fuels are investigated: methanol (Pc = 7.9 MPa), n-heptane (Pc = 2.74 MPa), n-hexane (Pc = 3.01 MPa) and n-octane (Pc = 2.48 MPa).

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

    Science.gov (United States)

    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.

  15. Steady State Investigations of DPF Soot Burn Rates and DPF Modeling

    DEFF Research Database (Denmark)

    Cordtz, Rasmus Lage; Ivarsson, Anders; Schramm, Jesper

    2011-01-01

    mass of a sample gas continuously extracted from the engine exhaust pipe for 1-2 hours while also measuring the gas flow passed through the filter. A small silicon carbide wall flow DPF protected in a sealed stainless steel filter housing is used as sample filter. Measured DPF pressure drop...... characteristics are used to fit model constants of soot and filter properties. Measured DPF gas conversions and soot burn rates are used to fit model activation energies of four DPF regeneration reactions using O2 and NO2 as reactants. Modeled DPF pressure drops and soot burn rates are compared to the steady......This work presents the experimental investigation of Diesel Particulate Filter (DPF) regeneration and a calibration procedure of a 1D DPF simulation model based on the commercial software AVL BOOST v. 5.1. Model constants and parameters are fitted on the basis of a number of steady state DPF...

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

    Science.gov (United States)

    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.

  17. High-fidelity plasma codes for burn physics

    Energy Technology Data Exchange (ETDEWEB)

    Cooley, James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Graziani, Frank [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Marinak, Marty [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Murillo, Michael [Michigan State Univ., East Lansing, MI (United States)

    2016-10-19

    Accurate predictions of equation of state (EOS), ionic and electronic transport properties are of critical importance for high-energy-density plasma science. Transport coefficients inform radiation-hydrodynamic codes and impact diagnostic interpretation, which in turn impacts our understanding of the development of instabilities, the overall energy balance of burning plasmas, and the efficacy of self-heating from charged-particle stopping. Important processes include thermal and electrical conduction, electron-ion coupling, inter-diffusion, ion viscosity, and charged particle stopping. However, uncertainties in these coefficients are not well established. Fundamental plasma science codes, also called high-fidelity plasma codes, are a relatively recent computational tool that augments both experimental data and theoretical foundations of transport coefficients. This paper addresses the current status of HFPC codes and their future development, and the potential impact they play in improving the predictive capability of the multi-physics hydrodynamic codes used in HED design.

  18. High-fidelity plasma codes for burn physics

    Energy Technology Data Exchange (ETDEWEB)

    Cooley, James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Graziani, Frank [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Marinak, Marty [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Murillo, Michael [Michigan State Univ., East Lansing, MI (United States)

    2016-10-19

    Accurate predictions of equation of state (EOS), ionic and electronic transport properties are of critical importance for high-energy-density plasma science. Transport coefficients inform radiationhydrodynamic codes and impact diagnostic interpretation, which in turn impacts our understanding of the development of instabilities, the overall energy balance of burning plasmas, and the efficacy of selfheating from charged-particle stopping. Important processes include thermal and electrical conduction, electron-ion coupling, inter-diffusion, ion viscosity, and charged particle stopping. However, uncertainties in these coefficients are not well established. Fundamental plasma science codes, also called high-fidelity plasma codes are a relatively recent computational tool that augments both experimental data and theoretical foundations of transport coefficients. This paper addresses the current status of HFPC codes and their future development, and the potential impact they play in improving the predictive capability of the multi-physics hydrodynamic codes used in HED design.

  19. The hydrogen–air burning rate near the lean flammability limit

    OpenAIRE

    Fernández Galisteo, Daniel; Sánchez Pérez, Antonio Luis; Liñán Martínez, Amable; Williams, F. A.

    2009-01-01

    This paper investigates the inner structure of the thin reactive layer of hydrogen–air fuellean deflagrations close to the flammability limit. The analysis, which employs seven elementary reactions for the chemistry description, uses the ratio of the characteristic radical and fuel concentrations as a small asymptotic parameter, enabling an accurate analytic expression for the resulting burning rate to be derived. The analysis reveals that the steady-state assumption for chemical intermedi...

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

    Science.gov (United States)

    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.

  1. Effect of Burning Rate Modifiers on Subatmospheric Flame Temperatures of AP/HTPB Composite Solid Propellants

    Directory of Open Access Journals (Sweden)

    S. Krishnan

    1998-04-01

    Full Text Available Using 30 um. pt and Pt 13 percent Rh thermocouples, flame temperatures of uncatalysed andcatalysed ammonium perchlorate/hydroxyl-terminated polybutadiene (AP/lffPB composite solidpropellants were measured under subatmospheric conditions. Ferric oxide F e 2 and copper chromite(CC were the catalysts used. The study demonstrates that Fe2O3 catalysed propellant, notwithstandingits least combustion efficiency undt;r subatmospheric conditions and weak gas-phase flame, has themaximum burning rate enhancement. This is argued to be due to the increased surface and subsurfacereactions caused by Fe2O3. CC-catalysed propellant burns to the least subatmospheric pressure withminimum loss in combustion efficiency indicating that this class of propellant may be more suitablefor base-bleed applications.

  2. Using "The Burns Suite" as a Novel High Fidelity Simulation Tool for Interprofessional and Teamwork Training.

    Science.gov (United States)

    Sadideen, Hazim; Wilson, David; Moiemen, Naiem; Kneebone, Roger

    2016-01-01

    Educational theory highlights the importance of contextualized simulation for effective learning. The authors recently published the concept of "The Burns Suite" (TBS) as a novel tool to advance the delivery of burns education for residents/clinicians. Effectively, TBS represents a low-cost, high-fidelity, portable, immersive simulation environment. Recently, simulation-based team training (SBTT) has been advocated as a means to improve interprofessional practice. The authors aimed to explore the role of TBS in SBTT. A realistic pediatric burn resuscitation scenario was designed based on "advanced trauma and life support" and "emergency management of severe burns" principles, refined utilizing expert opinion through cognitive task analysis. The focus of this analysis was on nontechnical and interpersonal skills of clinicians and nurses within the scenario, mirroring what happens in real life. Five-point Likert-type questionnaires were developed for face and content validity. Cronbach's alpha was calculated for scale reliability. Semistructured interviews captured responses for qualitative thematic analysis allowing for data triangulation. Twenty-two participants completed TBS resuscitation scenario. Mean face and content validity ratings were high (4.4 and 4.7 respectively; range 4-5). The internal consistency of questions was high. Qualitative data analysis revealed two new themes. Participants reported that the experience felt particularly authentic because the simulation had high psychological and social fidelity, and there was a demand for such a facility to be made available to improve nontechnical skills and interprofessional relations. TBS provides a realistic, novel tool for SBTT, addressing both nontechnical and interprofessional team skills. Recreating clinical challenge is crucial to optimize SBTT. With a better understanding of the theories underpinning simulation and interprofessional education, future simulation scenarios can be designed to provide

  3. Use of Closed Vessel as a Constant Pressure Apparatus for the Measurement of the Rate of Burning of Propellants

    Directory of Open Access Journals (Sweden)

    D. Vittal

    1980-04-01

    Full Text Available A method for the determination of burning rates of propellants whose from function is unknown is introduced. The method consists of burning in the closed vessel, a known charge weight of the test propellant alongwith a known pressure which remains nearly constant during the burning of the test propellant whose web size is the only quantity required for the evaluation of its rate of burning. The test propellants burns at near constant pressure conditions just as in the strand burner technique. This method can be applied to any unknown propellant of any shape whose web size can be measured and very large webs also can be used. In addition, the measurement of the records and the computation are very simple.

  4. Burning rate characteristics of energetic CMDB propellants. Part 2. Effect of HMX addition; Ko enerugi CMDB suishin yaku no nensho sokudo tokusei ( II ) - HMX tenka no koka -

    Energy Technology Data Exchange (ETDEWEB)

    Aoki, I. [Nissan Motor Co. Ltd. (Japan)

    1997-08-01

    Burning rate and specific impulse of a solid propellant are extremely important parameters in a design of a solid rocket motor. In this study, the relations between the burning rate and the amount of energy contained in HMX-CMDB propellants wherein the amount of energy is varied by adding HMX (High Melting Point Explosive). The following results are obtained. The final flame temperature is getting higher when the amount of energy is increased by adding HMX into a double-base propellant. The higher the final flame temperature is, the lower the burning rate is. Dark zone temperature, as a physical property, is lowered when the containing amount of energy is increased by adding HMX into the double-base propellant. This is because that, when weight fraction of HMX is increased, reaction heat at burning surface decreases, and the reaction in fizz zone is getting slower. The higher the dark zone temperature is, the higher the burning rate is. 20 refs., 11 figs., 1 tab.

  5. A pilot evaluation study of high resolution digital thermal imaging in the assessment of burn depth.

    Science.gov (United States)

    Hardwicke, Joseph; Thomson, Richard; Bamford, Amy; Moiemen, Naiem

    2013-02-01

    Thermal imaging is a tool that can be used to determine burn depth. We have revisited the use of this technology in the assessment of burns and aim to establish if high resolution, real-time technology can be practically used in conjunction with clinical examination to determine burn depth. 11 patients with burns affecting upper and lower limbs and the anterior and posterior trunk were included in this study. Digital and thermal images were recorded at between 42 h and 5 days post burn. When compared to skin temperature, full thickness burns were significantly cooler (pburns (pburns were not significantly different in temperature than non-burnt skin (p>0.05). Typically, full thickness burns were 2.3°C cooler than non-burnt skin; deep partial thickness burns were 1.2°C cooler than non-burnt skin; whilst superficial burns were only 0.1°C cooler. Thermal imaging can correctly determine difference in burn depth. The thermal camera produces images of high resolution and is quick and easy to use. Copyright © 2012 Elsevier Ltd and ISBI. All rights reserved.

  6. Effect of Surface Microstructure on the Temperature sensitivity of Burning Rate of Ammonium Perchlorate

    Directory of Open Access Journals (Sweden)

    K. Kishore

    1997-04-01

    Full Text Available Considering Vielle's law and the new thermodynamic model which the authors have developed recently the true dependence of temperature sensitivity of burning rate of ammonium perchlorate (AP on pressure is resolved and experimentally verified for bellet burning. The value of decreases with pressure steeply in regime I' (below 20 atm, but gently in regime I (above 20 atm. The value of powder AP has been determined and it is observed that (powder > (pellet, which clearly suggests that of is innuenced by the surface temperature sensitive parameter and hence by the surface/subsurface microstructure. In powder burning, the buoyant lifting of the particles into the gas phase occurs, Which constitutes the so-called 'free board region' (FER extending just above the true surface. Consequent to the decomposition of AP particles in FER, the condensed phase heat release gets curtailed and (powder becomes larger. A general relationship for in terms of density and surface temperature is suggested, which is applicable to both pellet and powder AP.

  7. Reduced rate of adenosine triphosphate synthesis by in vivo 31P nuclear magnetic resonance spectroscopy and downregulation of PGC-1beta in distal skeletal muscle following burn.

    Science.gov (United States)

    Tzika, A Aria; Mintzopoulos, Dionyssios; Padfield, Katie; Wilhelmy, Julie; Mindrinos, Michael N; Yu, Hongue; Cao, Haihui; Zhang, Qunhao; Astrakas, Loukas G; Zhang, Jiangwen; Yu, Yong-Ming; Rahme, Laurence G; Tompkins, Ronald G

    2008-02-01

    Using a mouse model of burn trauma, we tested the hypothesis that severe burn trauma corresponding to 30% of total body surface area (TBSA) causes reduction in adenosine triphosphate (ATP) synthesis in distal skeletal muscle. We employed in vivo 31P nuclear magnetic resonance (NMR) in intact mice to assess the rate of ATP synthesis, and characterized the concomitant gene expression patterns in skeletal muscle in burned (30% TBSA) versus control mice. Our NMR results showed a significantly reduced rate of ATP synthesis and were complemented by genomic results showing downregulation of the ATP synthase mitochondrial F1 F0 complex and PGC-1beta gene expression. Our findings suggest that inflammation and muscle atrophy in burns are due to a reduced ATP synthesis rate that may be regulated upstream by PGC-1beta. These findings implicate mitochondrial dysfunction in distal skeletal muscle following burn injury. That PGC-1beta is a highly inducible factor in most tissues and responds to common calcium and cyclic adenosine monophosphate (cAMP) signaling pathways strongly suggests that it may be possible to develop drugs that can induce PGC-1beta.

  8. High rate drift chambers

    Energy Technology Data Exchange (ETDEWEB)

    Christian, D.C. (Fermilab, Batavia, IL 60510 (United States)); Berisso, M.C. (Fermilab, Batavia, IL 60510 (United States)); Gutierrez, G. (Fermilab, Batavia, IL 60510 (United States)); Holmes, S.D. (Fermilab, Batavia, IL 60510 (United States)); Wehmann, A. (Fermilab, Batavia, IL 60510 (United States)); Avilez, C. (Instituto de Fisica, Universidad de Guanajuato, Leon, Guanajuato (Mexico)); Felix, J. (Instituto de Fisica, Universidad de Guanajuato, Leon, Guanajuato (Mexico)); Moreno, G. (Instituto de Fisica, Universidad de Guanajuato, Leon, Guanajuato (Mexico)); Romero, M. (Instituto de Fisica, Universidad de Guanajuato, Leon, Guanajuato (Mexico)); Sosa, M. (Instituto de Fisica, Universidad de Guanajuato, Leon, Guanajuato (Mexico)); Forbush, M. (Department of Physics, Texas A and M University, College Station, TX 77843 (United States)); Huson, F.R. (Department of Physics, Texas A and M University, College Station, TX 77843 (United States)); Wightman, J.A. (Department of Physi

    1994-06-01

    Fermilab experiment 690, a study of target dissociation reactions pp[yields]pX using an 800 GeV/c proton beam and a liquid hydrogen target, collected data in late 1991. The incident beam and 600-800 GeV/c scattered protons were measured using a system of six 6 in.x4 in. and two 15 in.x8 in. pressurized drift chambers spaced over 260 m. These chambers provided precise measurements at rates above 10 MHz (2 MHz per cm of sense wire). The measurement resolution of the smaller chambers was 90 [mu]m, and the resolution of the larger chambers was 125 [mu]m. Construction details and performance results, including radiation damage, are presented. ((orig.))

  9. Effect of Air Staging Ratios on the Burning Rate and Emissions in an Underfeed Fixed-Bed Biomass Combustor

    Directory of Open Access Journals (Sweden)

    Araceli Regueiro

    2016-11-01

    Full Text Available This experimental work studies a small-scale biomass combustor (5–12 kW with an underfed fixed bed using low air staging ratios (15%–30%. This document focuses on the influence of the operative parameters on the combustion process, so gaseous emissions and the distribution and concentration of particulate matter have also been recorded. The facility shows good stability and test repeatability. For the studied airflow ranges, the results show that increasing the total airflow rate does not increase the overall air excess ratio because the burning rate is proportionally enhanced (with some slight differences that depend on the air staging ratio. Consequently, the heterogeneous reactions at the bed remain in the so-called oxygen-limited region, and thus the entire bed operates under sub-stoichiometric conditions with regards of the char content of the biomass. In addition, tests using only primary air (no staging may increase the fuel consumption, but in a highly incomplete way, approaching a gasification regime. Some measured burning rates are almost 40% higher than previous results obtained in batch combustors due to the fixed position of the ignition front. The recorded concentration of particulate matter varies between 15 and 75 mg/Nm3, with a main characteristic diameter between 50 and 100 nm.

  10. Non-explosive hydrogen and helium burnings Abundance predictions from the NACRE reaction rate compilation

    CERN Document Server

    Arnould, M; Jorissen, A

    1999-01-01

    The abundances of the isotopes of the elements from C to Al produced by the non-explosive CNO, NeNa and MgAl modes of hydrogen burning, as well as by helium burning, are calculated with the thermonuclear rates recommended by the European compilation of reaction rates for astrophysics (NACRE: details about NACRE may be found at http://astro.ulb.ac.be. This electronic address provides many data of nuclear astrophysics interest and also offers the possibility of generating interactively tables of reaction rates for networks and temperature grids selected by the user). The impact of nuclear physics uncertainties on the derived abundances is discussed in the framework of a simple parametric astrophysical model. These calculations have the virtue of being a guide in the selection of the nuclear uncertainties that have to be duly analyzed in detailed model stars, particularly in order to perform meaningful confrontations between abundance observations and predictions. They are also hoped to help nuclear astrophysici...

  11. 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

    Institute of Scientific and Technical Information of China (English)

    Guofeng Shen; Miao Xue; Siye Wei; Yuanchen Chen; Bin Wang; Rong Wang; Huizhong Shen

    2013-01-01

    The uncertainty in emission estimation is strongly associated with the variation in emission factor (EF),which could be influenced bya variety of factors such as fuel properties,stove type,fire management and even methods used in measurements.The impacts of thesefactors are complicated and often interact with each other.Controlled burning experiments were conducted to investigate the influencesof fuel mass load,air supply and burning rate on the emissions and size distributions of carbonaceous particulate matter (PM) fromindoor corn straw bunting in a cooking stove.The results showed that the EFs of PM (EFpM),organic carbon (EFoc) and elementalcarbon (EFEc) were independent of the fuel mass load.The differences among them under different burning rates or air supply amountswere also found to be insignificant (P > 0.05) in the tested circumstances.PM from the indoor corn straw burning was dominated byfine PM with diameter less than 2.1 μm,contributing 86.4% ± 3.9% of the total.The size distribution of PM was influenced by theburning rate and 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 correlatedwith each other (P < 0.05),but they were not significantly correlated with the EF of co-emitted CO,suggesting that special attentionshould be paid to the use of CO as a surrogate for other incomplete combustion pollutants.

  12. Scald Burns

    Science.gov (United States)

    Safety Tips & Info Scald Burns Thousands of scald burns occur annually, and ALL are preventable! The two high-risk populations are children under the age ... the single most important factor in preventing scald burns. Increased awareness is the key to scald prevention! ...

  13. A comprehensive biomass burning emission inventory with high spatial and temporal resolution in China

    Science.gov (United States)

    Zhou, Ying; Xing, Xiaofan; Lang, Jianlei; Chen, Dongsheng; Cheng, Shuiyuan; Wei, Lin; Wei, Xiao; Liu, Chao

    2017-02-01

    . As for the straw burning emission of various crops, corn straw burning has the largest contribution to all of the pollutants considered, except for CH4; rice straw burning has highest contribution to CH4 and the second largest contribution to other pollutants, except for SO2, OC, and Hg; wheat straw burning is the second largest contributor to SO2, OC, and Hg and the third largest contributor to other pollutants. Heilongjiang, Shandong, and Henan provinces located in the north-eastern and central-southern regions of China have higher emissions compared to other provinces in China. Gridded emissions, which were obtained through spatial allocation based on the gridded rural population and fire point data from emission inventories at county resolution, could better represent the actual situation. High biomass burning emissions are concentrated in the areas with more agricultural and rural activity. The months of April, May, June, and October account for 65 % of emissions from in-field crop residue burning, while, regarding EC, the emissions in January, February, October, November, and December are relatively higher than other months due to biomass domestic burning in heating season. There are regional differences in the monthly variations of emissions due to the diversity of main planted crops and climatic conditions. Furthermore, PM2.5 component results showed that OC, Cl-, EC, K+, NH4+, elemental K, and SO42- are the main PM2.5 species, accounting for 80 % of the total emissions. The species with relatively high contribution to NMVOC emission include ethylene, propylene, toluene, mp-xylene, and ethyl benzene, which are key species for the formation of secondary air pollution. The detailed biomass burning emission inventory developed by this study could provide useful information for air-quality modelling and could support the development of appropriate pollution-control strategies.

  14. Evaluation of Ferrocene Derivatives as Burn Rate Modifiers in AP/HTPB-Based Composite Propellants

    Directory of Open Access Journals (Sweden)

    G. M. Gore

    1999-04-01

    Full Text Available Some ferrocene derivatives like 2,4-dinitrophenylhydrazine derivative of acetyl ferrocene, 1-pyrrolidinylmethyl ferrocene, di-ter-butyl ferrocene and 1,3-diferrocenyl-l-butene (DFB have been synthesised and characterised by infrared, nuclear magnetic resonance, ultraviolet, iron content, etc. To study the effect of their incorporation on performance, ammonium perchlorate/hydroxyl-terminated polybutadiene-based composite propellants containing these derivatives have been prepared and studied for burn rates, tensile strength and percentage elongation followed by their static test evaluation. A comparison of the properties of propellant containing solid and liquid ferrocene derivatives has been made with those containing Fe/sub 2/O/sub 3/ and n-butyl ferrocene, respectively. The data clearly indicates that these ferrocene derivatives are better than Fe/sub 2/O/sub 3/ and n-butyl errocene. Also, DFB is the best among these derivatives. Like composite propellants, DFB increases burn rate in fuel-rich propellants also.

  15. Measurement of elasticity and transepidermal water loss rate of burn scars with the Dermalab(®).

    Science.gov (United States)

    Anthonissen, Mieke; Daly, Daniel; Fieuws, Steffen; Massagé, Patrick; Van Brussel, Michel; Vranckx, Jan; Van den Kerckhove, Eric

    2013-05-01

    This cross-sectional study investigated the reproducibility of repeated elasticity and transepidermal water loss (TEWL) measurements with the DermaLab(®) on 32 active burn scars and healthy skin. Intra- and inter-observer reproducibility was examined by means of intra-class correlation coefficients (ICC) and standard error of measurements (SEM). Results showed good ICC values and rather high SEM values for inter- and intra-observer reproducibility of elasticity measurements. For TEWL measurements, ICC values were good and SEM values were high for inter- and intra-observer reproducibility. There was a significant difference between the estimated mean elasticity values of normal skin and grafted scars and between normal skin and spontaneously healed scars (p≤0.003). For the estimated mean TEWL values, there was a significant difference between normal skin and spontaneously healed scars (p=0.036). A significant negative relation was reported between mean TEWL and time after burn (p=0.008). In clinical trials it is necessary to interpret patient-specific changes in elasticity and TEWL with caution, since the SEMs of both modes are rather high. We therefore recommend the use of a mean of repeated measurements of elasticity and TEWL to decrease the SEM.

  16. Burn Rehabilitation

    Directory of Open Access Journals (Sweden)

    Koray Aydemir

    2011-07-01

    Full Text Available Burn injuries are important in terms of causing serious disability and threatening life. With the establishment of modern burn treatment units and advances in acute care management contributed to a reduced mortality rate over the last decades. As a result of improved outcome, more attention has to be given to a comprehensive burn rehabilitation program. Burn rehabilitation is a process that starts from day of admission and continues for months or sometimes years after the initial event. The term ‘burn rehabilitation’ incorporates the physical, physiological and social aspects of care. Burns can leave a patient with severely debilitating and deforming contractures, which can lead to significant disability when left untreated. Burn rehabilitation aims to prevent the possible complications, minimalize joint contractures and deformities, increase range of motion, control hypertrophic scarring, achieve the best possible functional capacity and to regain the patients vocational and recreational activities. (Journal of the Turkish Society Intensive Care 2011; 9 Suppl: 70-7

  17. EBSD and TEM characterization of high burn-up mixed oxide fuel

    Science.gov (United States)

    Teague, Melissa; Gorman, Brian; Miller, Brandon; King, Jeffrey

    2014-01-01

    Understanding and studying the irradiation behavior of high burn-up oxide fuel is critical to licensing of future fast breeder reactors. Advancements in experimental techniques and equipment are allowing for new insights into previously irradiated samples. In this work dual column focused ion beam (FIB)/scanning electron microscope (SEM) was utilized to prepared transmission electron microscope samples from mixed oxide fuel with a burn-up of 6.7% FIMA. Utilizing the FIB/SEM for preparation resulted in samples with a dose rate of <0.5 mRem/h compared to ∼1.1 R/h for a traditionally prepared TEM sample. The TEM analysis showed that the sample taken from the cooler rim region of the fuel pellet had ∼2.5× higher dislocation density than that of the sample taken from the mid-radius due to the lower irradiation temperature of the rim. The dual column FIB/SEM was additionally used to prepared and serially slice ∼25 μm cubes. High quality electron back scatter diffraction (EBSD) were collected from the face at each step, showing, for the first time, the ability to obtain EBSD data from high activity irradiated fuel.

  18. Systematic approach to verification and validation: High explosive burn models

    Energy Technology Data Exchange (ETDEWEB)

    Menikoff, Ralph [Los Alamos National Laboratory; Scovel, Christina A. [Los Alamos National Laboratory

    2012-04-16

    Most material models used in numerical simulations are based on heuristics and empirically calibrated to experimental data. For a specific model, key questions are determining its domain of applicability and assessing its relative merits compared to other models. Answering these questions should be a part of model verification and validation (V and V). Here, we focus on V and V of high explosive models. Typically, model developers implemented their model in their own hydro code and use different sets of experiments to calibrate model parameters. Rarely can one find in the literature simulation results for different models of the same experiment. Consequently, it is difficult to assess objectively the relative merits of different models. This situation results in part from the fact that experimental data is scattered through the literature (articles in journals and conference proceedings) and that the printed literature does not allow the reader to obtain data from a figure in electronic form needed to make detailed comparisons among experiments and simulations. In addition, it is very time consuming to set up and run simulations to compare different models over sufficiently many experiments to cover the range of phenomena of interest. The first difficulty could be overcome if the research community were to support an online web based database. The second difficulty can be greatly reduced by automating procedures to set up and run simulations of similar types of experiments. Moreover, automated testing would be greatly facilitated if the data files obtained from a database were in a standard format that contained key experimental parameters as meta-data in a header to the data file. To illustrate our approach to V and V, we have developed a high explosive database (HED) at LANL. It now contains a large number of shock initiation experiments. Utilizing the header information in a data file from HED, we have written scripts to generate an input file for a hydro code

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

    Science.gov (United States)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Yi Jianhua [Xi' an Modern Chemistry Research Institute, Xi' an 710065 (China); Zhao Fengqi, E-mail: yiren@nwu.edu.cn [Xi' an Modern Chemistry Research Institute, Xi' an 710065 (China); Wang Bozhou; Liu Qian; Zhou Cheng; Hu Rongzu [Xi' an Modern Chemistry Research Institute, Xi' an 710065 (China); Ren Yinghui [School of Chemical Engineering, Northwest University, Xi' an 710069 (China); Xu Siyu [Xi' an Modern Chemistry Research Institute, Xi' an 710065 (China); Xu, Kang-Zhen [School of Chemical Engineering, Northwest University, Xi' an 710069 (China); Ren Xiaoning [Xi' an Modern Chemistry Research Institute, Xi' an 710065 (China)

    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}){sup 2}, and the kinetic equations are d{alpha}/dt=10{sup 19.24}(1-{alpha}){sup 2}e{sup -2.32x10{sup 4/T}} and d{alpha}/dt=10{sup 20.32}(1-{alpha}){sup 2}e{sup -2.43x10{sup 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.

  1. High-resolution mapping of biomass burning emissions in tropical regions across three continents

    Science.gov (United States)

    Shi, Yusheng; Matsunaga, Tsuneo; Saito, Makoto

    2015-04-01

    Biomass burning emissions from open vegetation fires (forest fires, savanna fires, agricultural waste burning), human waste and biofuel combustion contain large amounts of trace gases (e.g., CO2, CH4, and N2O) and aerosols (BC and OC), which significantly impact ecosystem productivity, global atmospheric chemistry, and climate . With the help of recently released satellite products, biomass density based on satellite and ground-based observation data, and spatial variable combustion factors, this study developed a new high-resolution emissions inventory for biomass burning in tropical regions across three continents in 2010. Emissions of trace gases and aerosols from open vegetation burning are estimated from burned areas, fuel loads, combustion factors, and emission factors. Burned areas were derived from MODIS MCD64A1 burned area product, fuel loads were mapped from biomass density data sets for herbaceous and tree-covered land based on satellite and ground-based observation data. To account for spatial heterogeneity in combustion factors, global fractional tree cover (MOD44B) and vegetation cover maps (MCD12Q1) were introduced to estimate the combustion factors in different regions by using their relationship with tree cover under less than 40%, between 40-60% and above 60% conditions. For emission factors, the average values for each fuel type from field measurements are used. In addition to biomass burning from open vegetation fires, the emissions from human waste (residential and dump) burning and biofuel burning in 2010 were also estimated for 76 countries in tropical regions across the three continents and then allocated into each pixel with 1 km grid based on the population density (Gridded Population of the World v3). Our total estimates for the tropical regions across the three continents in 2010 were 17744.5 Tg CO2, 730.3 Tg CO, 32.0 Tg CH4, 31.6 Tg NOx, 119.2 Tg NMOC, 6.3 Tg SO2, 9.8 NH3 Tg, 81.8 Tg PM2.5, 48.0 Tg OC, and 5.7 Tg BC, respectively. Open

  2. Levoglucosan indicates high levels of biomass burning aerosols over oceans from the Arctic to Antarctic

    Science.gov (United States)

    Hu, Q.; Xie, Z.; Wang, X.; Kang, H.; Zhang, P.

    2015-12-01

    Biomass burning discharges numerous kinds of gases and aerosols, such as carbon dioxide (CO2), carbon monoxide (CO), methane (CH4), black carbon (BC), alcohols, organic acids and persistent organic pollutants (POPs), and is known to affect air quality, global carbon cycle, and climate. However, the extent to which biomass burning gases/aerosols are present on a global scale, especially in the marine atmosphere, is poorly understood. Here we measure levoglucosan, a superior molecular tracer of biomass burning aerosols because of its single source, in marine air from the Arctic Ocean through the North and South Pacific Ocean to coastal Antarctica during burning season. Levoglucosan was found to be present in all regions at ng/m3 levels. As a whole, levoglucosan concentrations in the Southern Hemisphere were comparable to those in the Northern Hemisphere. Marine air in the mid-latitudes (30°-60° N and S) has the highest levoglucosan loading due to the emission from adjacent lands. Air over the Arctic Ocean which affected by biomass burning in the east Siberia has intermediate loading. Equatorial latitudes is the main source of biomass burning emissions, however, levoglucosan is in relatively low level. Large amount of precipitation and high hydroxyl radical concentration in this region cause more deposition and degradation of levoglucosan during transport. Previous studies were debatable on the influence of biomass burning on the Antarctic because of uncertain source of BC. Here via levoglucosan, it is proved that although far away from emission sources, the Antarctic is still affected by biomass burning aerosols which may be derived from South America. Biomass burning has a significant impact on mercury (Hg) and water-soluble organic carbon (WSOC) in marine aerosols from pole to pole, with more contribution to WSOC in the Northern Hemisphere than in the Southern Hemisphere.

  3. Using High Spatial Resolution Satellite Imagery to Map Forest Burn Severity Across Spatial Scales in a Pine Barrens Ecosystem

    Science.gov (United States)

    Meng, Ran; Wu, Jin; Schwager, Kathy L.; Zhao, Feng; Dennison, Philip E.; Cook, Bruce D.; Brewster, Kristen; Green, Timothy M.; Serbin, Shawn P.

    2017-01-01

    As a primary disturbance agent, fire significantly influences local processes and services of forest ecosystems. Although a variety of remote sensing based approaches have been developed and applied to Landsat mission imagery to infer burn severity at 30 m spatial resolution, forest burn severity have still been seldom assessed at fine spatial scales (less than or equal to 5 m) from very-high-resolution (VHR) data. We assessed a 432 ha forest fire that occurred in April 2012 on Long Island, New York, within the Pine Barrens region, a unique but imperiled fire-dependent ecosystem in the northeastern United States. The mapping of forest burn severity was explored here at fine spatial scales, for the first time using remotely sensed spectral indices and a set of Multiple Endmember Spectral Mixture Analysis (MESMA) fraction images from bi-temporal - pre- and post-fire event - WorldView-2 (WV-2) imagery at 2 m spatial resolution. We first evaluated our approach using 1 m by 1 m validation points at the sub-crown scale per severity class (i.e. unburned, low, moderate, and high severity) from the post-fire 0.10 m color aerial ortho-photos; then, we validated the burn severity mapping of geo-referenced dominant tree crowns (crown scale) and 15 m by 15 m fixed-area plots (inter-crown scale) with the post-fire 0.10 m aerial ortho-photos and measured crown information of twenty forest inventory plots. Our approach can accurately assess forest burn severity at the sub-crown (overall accuracy is 84% with a Kappa value of 0.77), crown (overall accuracy is 82% with a Kappa value of 0.76), and inter-crown scales (89% of the variation in estimated burn severity ratings (i.e. Geo-Composite Burn Index (CBI)). This work highlights that forest burn severity mapping from VHR data can capture heterogeneous fire patterns at fine spatial scales over the large spatial extents. This is important since most ecological processes associated with fire effects vary at the less than 30 m scale and

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

    NARCIS (Netherlands)

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

    2013-01-01

    Recent studies based on trace gas mixing ratios in ice cores and charcoal data indicate that biomass burning emissions over the past millennium exceeded contemporary emissions by up to a factor of 4 for certain time periods. This is surprising because various sources of biomass burning are linked wi

  5. Instant release fraction and matrix release of high burn-up UO2 spent nuclear fuel: Effect of high burn-up structure and leaching solution composition

    Science.gov (United States)

    Serrano-Purroy, D.; Clarens, F.; González-Robles, E.; Glatz, J. P.; Wegen, D. H.; de Pablo, J.; Casas, I.; Giménez, J.; Martínez-Esparza, A.

    2012-08-01

    Two weak points in Performance Assessment (PA) exercises regarding the alteration of Spent Nuclear Fuel (SNF) are the contribution of the so-called Instant Release Fraction (IRF) and the effect of High Burn-Up Structure (HBS). This manuscript focuses on the effect of HBS in matrix (long term) and instant release of a Pressurised Water Reactor (PWR) SNF irradiated in a commercial reactor with a mean Burn-Up (BU) of 60 GWd/tU. In order to study the HBS contribution, two samples from different radial positions have been prepared. One from the centre of the SNF, labelled CORE, and one from the periphery, enriched with HBS and labelled OUT. Static leaching experiments have been carried out with two synthetic leaching solutions: bicarbonate (BIC) and Bentonitic Granitic Groundwater (BGW), and in all cases under oxidising conditions. IRF values have been calculated from the determined Fraction of Inventory in Aqueous Phase (FIAP). In all studied cases, some radionuclides (RN): Rb, Sr and Cs, have shown higher release rates than uranium, especially at the beginning of the experiment, and have been considered as IRF. Redox sensitive RN like Mo and Tc have been found to dissolve slightly faster than uranium and further studies might be needed to confirm if they can also be considered part of the IRF. Most of the remaining studied RN, mainly actinides and lanthanides, have been found to dissolve congruently with the uranium matrix. Finally, Zr, Ru and Rh presented lower release rates than the matrix. Higher matrix release has been determined for CORE than for OUT samples showing that the formation of HBS might have a protective effect against the oxidative corrosion of the SNF. On the contrary, no significant differences have been observed between the two studied leaching solutions (BIC and BGW). Two different IRF contributions have been determined. One corresponding to the fraction of inventory segregated in the external open grain boundaries, directly available to water and

  6. Nutrition Support in Burn Patients

    Directory of Open Access Journals (Sweden)

    Cem Aydoğan

    2012-08-01

    Full Text Available Severe burn trauma causes serious metabolic derangements. Increased metabolic rate which is apart of a pathophysiologic characteristic of burn trauma results in protein-energy malnutrition. This situation causes impaired wound healing, muscle and fat tissue’s breakdown, growth retardation in children and infections. Nutrition support is vital in the treatment strategies of burn victims to prevent high mortal and disabling complications in this devastating trauma. Our aim in this study is to review management of nutrition in burn victims. (Journal of the Turkish Society Intensive Care 2012; 10: 74-83

  7. Biomass burning in eastern Europe during spring 2006 caused high deposition of ammonium in northern Fennoscandia

    DEFF Research Database (Denmark)

    Karlsson, Per Erik; Ferm, Martin; Pihl Karlsson, Gunilla

    2013-01-01

    High air concentrations of ammonium were detected at low and high altitude sites in Sweden, Finland and Norway during the spring 2006, coinciding with polluted air from biomass burning in eastern Europe passing over central and northern Fennoscandia. Unusually high values for throughfall deposition...

  8. Fatigue crack growth behaviors of a new burn-resistant highly-stabilized beta titanium alloy

    Institute of Scientific and Technical Information of China (English)

    WU Huan; ZHAO Yongqing; ZENG Weidong; QIAN Li

    2009-01-01

    This article presents the fatigue crack growth (FCG) behaviors of a new burn-resistant highly-stabilized beta Ti40 alloy. The FCG rotes were analyzed. The fracture surfaces and the side surfaces of the test samples were explored. The results show that frequency affects the cracking behaviors of Ti40 alloy. Temperature also plays an important role in Ti40 alloy cracking. At room temperature (25℃), when the frequency increases, the cracking rate changes a little in the range of low stress intensity factor (ΔK), while it changes significantly when ΔK is high. At 500℃, the cracking rate of Ti40 alloy changes significantly during all the course of clacking. The frequency also affects the microstructure patterns of Ti40 alloy. A number of secondary cracks appear in the area more than 200 μm from the main crack at a high ΔK when the fre-quency is 1 Hz, but only a few secondary cracks exist when the frequency is 10 Hz. Facet image is the main image of the fracture surfaces when the frequency is 1 Hz. While, ductile striation occupies most of the area of fracture surfaces when the frequency is 10 Hz.

  9. High Data Rate Quantum Cryptography

    Science.gov (United States)

    Kwiat, Paul; Christensen, Bradley; McCusker, Kevin; Kumor, Daniel; Gauthier, Daniel

    2015-05-01

    While quantum key distribution (QKD) systems are now commercially available, the data rate is a limiting factor for some desired applications (e.g., secure video transmission). Most QKD systems receive at most a single random bit per detection event, causing the data rate to be limited by the saturation of the single-photon detectors. Recent experiments have begun to explore using larger degree of freedoms, i.e., temporal or spatial qubits, to optimize the data rate. Here, we continue this exploration using entanglement in multiple degrees of freedom. That is, we use simultaneous temporal and polarization entanglement to reach up to 8.3 bits of randomness per coincident detection. Due to current technology, we are unable to fully secure the temporal degree of freedom against all possible future attacks; however, by assuming a technologically-limited eavesdropper, we are able to obtain 23.4 MB/s secure key rate across an optical table, after error reconciliation and privacy amplification. In this talk, we will describe our high-rate QKD experiment, with a short discussion on our work towards extending this system to ship-to-ship and ship-to-shore communication, aiming to secure the temporal degree of freedom and to implement a 30-km free-space link over a marine environment.

  10. Cu–Co–O nano-catalysts as a burn rate modifier for composite solid propellants

    Directory of Open Access Journals (Sweden)

    D. Chaitanya Kumar Rao

    2016-08-01

    Full Text Available Nano-catalysts containing copper–cobalt oxides (Cu–Co–O have been synthesized by the citric acid (CA complexing method. Copper (II nitrate and Cobalt (II nitrate were employed in different molar ratios as the starting reactants to prepare three types of nano-catalysts. Well crystalline nano-catalysts were produced after a period of 3 hours by the calcination of CA–Cu–Co–O precursors at 550 °C. The phase morphologies and crystal composition of synthesized nano-catalysts were examined using Scanning Electron Microscope (SEM, Energy Dispersive Spectroscopy (EDS and Fourier Transform Infrared Spectroscopy (FTIR methods. The particle size of nano-catalysts was observed in the range of 90 nm–200 nm. The prepared nano-catalysts were used to formulate propellant samples of various compositions which showed high reactivity toward the combustion of HTPB/AP-based composite solid propellants. The catalytic effects on the decomposition of propellant samples were found to be significant at higher temperatures. The combustion characteristics of composite solid propellants were significantly improved by the incorporation of nano-catalysts. Out of the three catalysts studied in the present work, CuCo-I was found to be the better catalyst in regard to thermal decomposition and burning nature of composite solid propellants. The improved performance of composite solid propellant can be attributed to the high crystallinity, low agglomeration and lowering the decomposition temperature of oxidizer by the addition of CuCo-I nano-catalyst.

  11. The visual analogue thermometer and the graphic numeric rating scale : A comparison of self-report instruments for pain measurement in adults with burns

    NARCIS (Netherlands)

    De Jong, A. E E; Bremer, M.; Hofland, H. W C; Schuurmans, M. J.; Middelkoop, E.; Van Loey, N. E E

    2015-01-01

    To evaluate the adequacy of pain management in burn care, pain measurement is essential. The visual analogue thermometer (VAT) and graphic numeric rating scale (GNRS) are frequently used self-report instruments for burn pain. To legitimise their interchangeable use in research and practice, we aimed

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

    Science.gov (United States)

    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.

  13. Intentional burns in Nepal: a comparative study.

    Science.gov (United States)

    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

  14. Investigations on high speed directly modulated microdisk lasers accounting for radial carrier hole burning

    Science.gov (United States)

    Huang, Yong-Zhen; Lv, Xiao-Meng; Zou, Ling-Xiu; Long, Heng; Xiao, Jin-Long; Yang, Yue-De; Du, Yun

    2014-04-01

    High-speed modulation characteristics are investigated for microdisk lasers theoretically and experimentally. In rate equation analysis, the microdisk resonator is radially divided into two regions under uniform carrier density approximation in each region. The injection current profile, carrier spatial hole burning, and diffusion are accounted for in the evaluation of small-signal modulation curves and the simulation of large-signal responses. The numerical results indicate that a wide mode field pattern in radial direction has merit for high-speed modulation, which is expected for coupled modes in the microdisk lasers connected with an output waveguide. For a 15-μm-radius microdisk laser connected with a 2-μm-wide output waveguide, the measured small-signal response curves with a low-frequency roll-off are well in agreement with the simulated result at a 2-μm radial width for the mode intensity distribution. The resonant frequencies of 7.2, 5.9, and 3.9 GHz are obtained at the temperatures of 287, 298, and 312 K from the small-signal response curves, and clear eye diagrams at 12.5 Gb/s with an extinction ratio of 6.1 dB are observed for the microdisk laser at the biasing current of 38 mA and 287 K.

  15. Revision of the 15N(p,{\\gamma})16O reaction rate and oxygen abundance in H-burning zones

    CERN Document Server

    Caciolli, A; Capogrosso, V; Bemmerer, D; Broggini, C; Corvisiero, P; Costantini, H; Elekes, Z; Formicola, A; Fulop, Zs; Gervino, G; Guglielmetti, A; Gustavino, C; Gyurky, Gy; Imbriani, G; Junker, M; Lemut, A; Marta, M; Menegazzo, R; Palmerini, S; Prati, P; Roca, V; Rolfs, C; Alvarez, C Rossi; Somorjai, E; Straniero, O; Strieder, F; Terrasi, F; Trautvetter, H P; Vomiero, A

    2011-01-01

    The NO cycle takes place in the deepest layer of a H-burning core or shell, when the temperature exceeds T {\\simeq} 30 {\\cdot} 106 K. The O depletion observed in some globular cluster giant stars, always associated with a Na enhancement, may be due to either a deep mixing during the RGB (red giant branch) phase of the star or to the pollution of the primordial gas by an early population of massive AGB (asymptotic giant branch) stars, whose chemical composition was modified by the hot bottom burning. In both cases, the NO cycle is responsible for the O depletion. The activation of this cycle depends on the rate of the 15N(p,{\\gamma})16O reaction. A precise evaluation of this reaction rate at temperatures as low as experienced in H-burning zones in stellar interiors is mandatory to understand the observed O abundances. We present a new measurement of the 15N(p,{\\gamma})16O reaction performed at LUNA covering for the first time the center of mass energy range 70-370 keV, which corresponds to stellar temperatures...

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

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, Marcia A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Oliver, Michael S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    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.

  17. Instant release of fission products in leaching experiments with high burn-up nuclear fuels in the framework of the Euratom project FIRST- Nuclides

    Science.gov (United States)

    Lemmens, K.; González-Robles, E.; Kienzler, B.; Curti, E.; Serrano-Purroy, D.; Sureda, R.; Martínez-Torrents, A.; Roth, O.; Slonszki, E.; Mennecart, T.; Günther-Leopold, I.; Hózer, Z.

    2017-02-01

    The instant release of fission products from high burn-up UO2 fuels and one MOX fuel was investigated by means of leach tests. The samples covered PWR and BWR fuels at average rod burn-up in the range of 45-63 GWd/tHM and included clad fuel segments, fuel segments with opened cladding, fuel fragments and fuel powder. The tests were performed with sodium chloride - bicarbonate solutions under oxidizing conditions and, for one test, in reducing Ar/H2 atmosphere. The iodine and cesium release could be partially explained by the differences in sample preparation, leading to different sizes and properties of the exposed surface areas. Iodine and cesium releases tend to correlate with FGR and linear power rating, but the scatter of the data is significant. Although the gap between the fuel and the cladding was closed in some high burn-up samples, fissures still provide possible preferential transport pathways.

  18. On the Sensitivity of Massive Star Nucleosynthesis and Evolution to Solar Abundances and to Uncertainties in Helium Burning Reaction Rates

    CERN Document Server

    Tur, Clarisse; Austin, Sam M

    2007-01-01

    We explore the dependence of pre-supernova evolution and supernova nucleosynthesis yields on the uncertainties in helium burning reaction rates. Using the revised solar abundances of Lodders (2003) for the initial stellar composition, instead of those of Anders & Grevesse (1989), changes the supernova yields and limits the constraints that those yields place on the 12C(a,g)16O reaction rate. The production factors of medium-weight elements (A = 16 to 40) were found to be in reasonable agreement with observed solar ratios within the current experimental uncertainties in the triple alpha reaction rate. Simultaneous variations by the same amount in both reaction rates or in either of them separately, however, can induce significant changes in the central 12C abundance at core carbon ignition and in the mass of the supernova remnant. It therefore remains important to have experimental determinations of the helium burning rates so that their ratio and absolute values are known with an accuracy of 10% or better...

  19. Burning rate characteristics of energetic CMDB propellants (III). Effect of initial propellant temperature; Ko energy CMDB suishinyaku no nensho sokudo tokusei (III). Suishinyaku shoki ondo no koka

    Energy Technology Data Exchange (ETDEWEB)

    Aoki, I. [Nissan Motor Co. Ltd., Tokyo (Japan)

    1998-01-01

    In case of double-base properants, the temperature sensitivity of burning rate for this type of propellants having higher energy becomes smaller than that of propellants having lower energy. When the energy contained in propellants increases, or initial propellant temperatures increase, the burning surface temperature of propellant increases, therefore, the reaction in fizz zone is accelerated, the dark zone temperature increases, and the temperature gradient in fizz zone increases. This increase of temperature gradient increases the burning rate of propellant. In case of HMX-CMDB propellants, when the energy contained in propellants increases, or initial propellant temperatures decrease, the burning surface temperature of propellant decreases, therefore, the reaction in fizz zone is decelerated, the dark zone temperature decreases, and the temperature gradient in fizz zone decreases. This decrease of temperature gradient decreases the burning rate of propellant. As a result, it was clarified that the temperatures as common physical properties which had an effect of initial propellant temperatures on the burning rates were the burning surface temperature and the dark zone temperature. 22 refs., 12 figs., 2 tabs.

  20. Organic functional groups in aerosol particles from burning and non-burning forest emissions at a high-elevation mountain site

    Directory of Open Access Journals (Sweden)

    S. Takahama

    2011-07-01

    Full Text Available Ambient particles collected on teflon filters at the Peak of Whistler Mountain, British Columbia (2182 m a.s.l. during spring and summer 2009 were measured by Fourier transform infrared (FTIR spectroscopy for organic functional groups (OFG. The project mean and standard deviation of organic aerosol mass concentrations (OM for all samples was 3.2±3.3 (μg m−3. Measurements of aerosol mass fragments, size, and number concentrations were used to separate fossil-fuel combustion and burning and non-burning forest sources of the measured organic aerosol. The OM was composed of the same anthropogenic and non-burning forest components observed at Whistler mid-valley in the spring of 2008; during the 2009 campaign, biomass burning aerosol was additionally observed from fire episodes occurring between June and September. On average, organic hydroxyl, alkane, carboxylic acid, ketone, and primary amine groups represented 31 %±11 %, 34 %±9 %, 23 %±6 %, 6 %±7 %, and 6 %±3 % of OM, respectively. Ketones in aerosols were associated with burning and non-burning forest origins, and represented up to 27 % of the OM. The organic aerosol fraction resided almost entirely in the submicron fraction without significant diurnal variations. OM/OC mass ratios ranged mostly between 2.0 and 2.2 and O/C atomic ratios between 0.57 and 0.76, indicating that the organic aerosol reaching the site was highly aged and possibly formed through secondary formation processes.

  1. High Burn-Up Spent Nuclear Fuel Vibration Integrity Study

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jy-An John [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wang, Hong [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jiang, Hao [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bevard, Bruce Balkcom [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Howard, Rob L [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Scaglione, John M [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-01-01

    The Oak Ridge National Laboratory (ORNL) has developed the cyclic integrated reversible-bending fatigue tester (CIRFT) approach to successfully demonstrate the controllable fatigue fracture on high burnup (HBU) spent nuclear fuel (SNF) in a normal vibration mode. CIRFT enables examination of the underlying mechanisms of SNF system dynamic performance. Due to the inhomogeneous composite structure of the SNF system, the detailed mechanisms of the pellet-pellet and pellet-clad interactions and the stress concentration effects at the pellet-pellet interface cannot be readily obtained from a CIRFT system measurement. Therefore, finite element analyses (FEAs) are used to translate the global moment-curvature measurement into local stress-strain profiles for further investigation. The major findings of CIRFT on the HBU SNF are as follows: SNF system interface bonding plays an important role in SNF vibration performance. Fuel structure contributes to SNF system stiffness. There are significant variations in stress and curvature of SNF systems during vibration cycles resulting from segment pellets and clad interactions. SNF failure initiates at the pellet-pellet interface region and appears to be spontaneous.

  2. The Correlation Between the Burning Features, the Burning Agent and Motivation in Burn Victims Attending Shahid Motahari Hospital in Tehran During 2009: letter to Editor

    Directory of Open Access Journals (Sweden)

    Kamran Aghakhani M.D.

    2011-06-01

    Full Text Available Burning is one of the commonest causes of death. Due to the high rate of death among burn victims epidemiological investigation of burning, burning agents and the relevant motivations can be of great preventive value.1 In this cross-sectional study all the hospitalized patients in Shahid Motahari Burn Hospital at Tehran city in the year 2009 were included in the study. The collected data were analyzed by SPSS (ver. 17 software. Out of the 1548 hospitalized patients for burn, 1134 (73.3% left hospital in good conditions, 47 (3% left in relatively good conditions, 289 (18.7% died and 78 (5% persons left the Hospital satisfactorily on their own volition. About two-thirds of the patients were men. The mean age of the burn victims was 27.9±18.3 years, 16% of them being 5 years old or younger. The highest percentage of burn area was 30% of the total body surface which was seen in 20 to 30-year old patients. 58.7% of burns had been caused by fire. 94% of the burns had happened accidentally, 5% by suicidal and 1% by homicidal acts. The highest percentage of burn was observed in patients in whom the burn agent was fire. Six (4% persons had first degree, 820 (53% persons had second degree and 722 (46.6% had third degree burns. In patients who had committed suicide third degree burns were higher than second degree burns (7.7% vs. 2%. 24.4% of women and 16.6% of men died due to the burns. The rate of death in patients less than 50 years of age was 18% but the figure increased to 24% in those above 50. A burn area less than or more than 10% was, respectively correlated with 2.1% and 22.1% of deaths. 34.8% of the patients with third degree burns and 4.6% of those with second and first degree burns died. 58.3% of the suicidal patient died due to the severity of the burns relative to 16.7% due to other causes. 89 (5.7% patients had respiratory tract burns and the death rate was 58.4% among these patients while the death rate was 16.2% in patients without

  3. Learn from the burn: The High Park Fire 5 years later

    Science.gov (United States)

    Sue Miller; Charles Rhodes; Pete Robichaud; Sandra Ryan; Jen Kovecses; Carl Chambers; Sara Rathburn; Jared Heath; Stephanie Kampf; Codie Wilson; Dan Brogan; Brad Piehl; Mary Ellen Miller; John Giordanengo; Erin Berryman; Monique Rocca

    2017-01-01

    It has been 5 years since the High Park Fire burned over 85,000 acres in Northern Colorado, causing extensive property damage, loss of life, and severe impacts to the water quality of the Poudre River. In the fall of 2016, a conference was organized by the USFS Rocky Mountain Research Station and the Coalition for the Poudre River Watershed to discuss what has been...

  4. High-resolution historical emission inventories of crop residue burning in fields in China for the period 1990-2013

    Science.gov (United States)

    Li, Jing; Li, Yaqi; Bo, Yu; Xie, Shaodong

    2016-08-01

    High-resolution historical emission inventories of crop residue burning in fields in China were developed for the period 1990-2013. More accurate time-varying statistical data and locally observed emission factors were utilized to estimate crop residue open burning emissions at provincial level. Then pollutants emissions were allocated to a high spatial resolution of 10 km × 10 km and a high temporal resolution of 1 day based on the Moderate Resolution Imaging Spectroradiometer (MODIS) Fire Product (MOD/MYD14A1). Results show that China's CO emissions have increased by 5.67 times at an annual average rate of 24% from 1.06 Tg in 1990 to 7.06 Tg in 2013; the emissions of CO2, CH4, NMVOCs, N2O, NOx, NH3, SO2, PM2.5, OC, and BC have increased by 595%, 500%, 608%, 584%, 600%, 600%, 543%, 571%, 775%, and 500%, respectively, over the past 24 years. Spatially, the regions with high emissions had been notable expanding over the years, especially in the central eastern districts, the Northeastern of China, and the Sichuan Basin. Strong temporal pattern were observed with the highest emissions in June, followed by March to May and October. This work provides a better understanding of the spatiotemporal representation of agricultural fire emissions in China and can benefit both air quality modeling and management with improved accuracy.

  5. Acute pain management in burn patients

    DEFF Research Database (Denmark)

    Gamst-Jensen, Hejdi; Vedel, Pernille Nygaard; Lindberg-Larsen, Viktoria Oline

    2014-01-01

    management addresses and alleviates these complications. The aim of our study was to compare clinical guidelines for pain management in burn patients in selected European and non-European countries. We included pediatric guidelines due to the high rate of children in burn units. METHOD: The study had...... patients. The most highly recommended guidelines provided clear and accurate recommendations for the nursing and medical staff on pain management in burn patients. We recommend the use of a validated appraisal tool such as the AGREE instrument to provide more consistent and evidence-based care to burn......OBJECTIVE: Burn patients suffer excruciating pain due to their injuries and procedures related to surgery, wound care, and mobilization. Acute Stress Disorder, Post-Traumatic Stress Disorder, chronic pain and depression are highly prevalent among survivors of severe burns. Evidence-based pain...

  6. RELATION BETWEEN PORE MODEL AND CENTER-LINE TEMPERATURE IN HIGH BURN-UP UO2 PELLET

    Directory of Open Access Journals (Sweden)

    Suwardi Suwardi

    2010-06-01

    Full Text Available Relation between pore model and center-line temperature of high burn up UO2 Pellet. Temperature distribution has been evaluated by using different model of pore distribution. Typical data of power distribution and coolant data have been chosen in this study. Different core model and core distribution model have been studied for related temperature, in correlation with high burn up thermal properties. Finite element combined finite different adapted from Saturn-1 has been used for calculating the temperature distribution. The center-line temperature for different pore model and related discussion is presented.   Keywords: pore model, high burn up, UO2 pellet, centerline temperature.

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

    Science.gov (United States)

    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.

  8. Family aggregation in a population of chronic arsenic poisoning associated with high arsenic coal burning

    Institute of Scientific and Technical Information of China (English)

    LinGF; ChenJG

    2002-01-01

    About 2600 cases of chronic arsenic poisoning (CAP) in Southwest China-Guizhou Povince represent a unique case of CAP in the world associated with indoor high As coal burning.An epidemiological investigation in 4 clans (694 subjects,male 299,female 395) was launched in one Cun(village) in JL area(21000 residents,about 2000 CAP cases).(1)Clan G(possible Hanized Yi origin).The ancestors,a couple settled here in Qing dynasty.CAP prevalence was 43.3%(93/215).It was found that in 9 of 25 brotherhood groups all the members suffered with CAP.(2) An non-consanguinous branch of family G.The ancestor,a boy was adopted by family G in 1890s.The incidence rate was 20.8%(11/53) which was lower than that in clan G(consanguineous)(P=0.00261,r=0.344),though both clans have been living in the same family for 4 generations.(3)Clan B(Han origin).The ancestor moved the family from Nanjing in Ming dynasty.The CAP prevalence is 45.5%(75/165).(4)Clan P(ethnic Miao).The CAP prevalence is 3.9(9/232),far less than other ethnic clans,for example,less than clan G (consanguineous)(P=3.706E=23,r=0.052944).The observation suggests possible family aggregation of CAP in high As coal using area.further work is required.

  9. Laminar Burning Velocities of Fuels for Advanced Combustion Engines (FACE) Gasoline and Gasoline Surrogates with and without Ethanol Blending Associated with Octane Rating

    KAUST Repository

    Mannaa, Ossama A.

    2016-05-04

    Laminar burning velocities of fuels for advanced combustion engines (FACE) C gasoline and of several blends of surrogate toluene reference fuels (TRFs) (n-heptane, iso-octane, and toluene mixtures) of the same research octane number are presented. Effects of ethanol addition on laminar flame speed of FACE-C and its surrogate are addressed. Measurements were conducted using a constant volume spherical combustion vessel in the constant pressure, stable flame regime at an initial temperature of 358 K and initial pressures up to 0.6 MPa with the equivalence ratios ranging from 0.8 to 1.6. Comparable values in the laminar burning velocities were measured for the FACE-C gasoline and the proposed surrogate fuel (17.60% n-heptane + 77.40% iso-octane + 5% toluene) over the range of experimental conditions. Sensitivity of flame propagation to total stretch rate effects and thermo-diffusive instability was quantified by determining Markstein length. Two percentages of an oxygenated fuel of ethanol as an additive, namely, 60 vol% and 85 vol% were investigated. The addition of ethanol to FACE-C and its surrogate TRF-1 (17.60% n-heptane + 77.40% iso-octane + 5% toluene) resulted in a relatively similar increase in the laminar burning velocities. The high-pressure measured values of Markstein length for the studied fuels blended with ethanol showed minimal influence of ethanol addition on the flame’s response to stretch rate and thermo-diffusive instability. © 2016 Taylor & Francis.

  10. Analysis of xRAGE and flag high explosive burn models with PBX 9404 cylinder tests

    Energy Technology Data Exchange (ETDEWEB)

    Harrier, Danielle [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Andersen, Kyle Richard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-08-05

    High explosives are energetic materials that release their chemical energy in a short interval of time. They are able to generate extreme heat and pressure by a shock driven chemical decomposition reaction, which makes them valuable tools that must be understood. This study investigated the accuracy and performance of two Los Alamos National Laboratory hydrodynamic codes, which are used to determine the behavior of explosives within a variety of systems: xRAGE which utilizes an Eulerian mesh, and FLAG with utilizes a Lagrangian mesh. Various programmed and reactive burn models within both codes were tested using a copper cylinder expansion test. The test was based on a recent experimental setup which contained the plastic bonded explosive PBX 9404. Detonation velocity versus time curves for this explosive were obtained using Photon Doppler Velocimetry (PDV). The modeled results from each of the burn models tested were then compared to one another and to the experimental results. This study validate

  11. Analysis of Xrage and Flag High Explosive Burn Models with PBX 9404 Cylinder Tests

    Science.gov (United States)

    Harrier, Danielle; Fessenden, Julianna; Ramsey, Scott

    2016-11-01

    High explosives are energetic materials that release their chemical energy in a short interval of time. They are able to generate extreme heat and pressure by a shock driven chemical decomposition reaction, which makes them valuable tools that must be understood. This study investigated the accuracy and performance of two Los Alamos National Laboratory hydrodynamic codes, which are used to determine the behavior of explosives within a variety of systems: xRAGE which utilizes an Eulerian mesh, and FLAG with utilizes a Lagrangian mesh. Various programmed and reactive burn models within both codes were tested, using a copper cylinder expansion test. The test was based off of a recent experimental setup which contained the plastic bonded explosive PBX 9404. Detonation velocity versus time curves for this explosive were obtained from the experimental velocity data collected using Photon Doppler Velocimetry (PDV). The modeled results from each of the burn models tested were then compared to one another and to the experimental results using the Jones-Wilkins-Lee (JWL) equation of state parameters that were determined and adjusted from the experimental tests. This study is important to validate the accuracy of our high explosive burn models and the calibrated EOS parameters, which are important for many research topics in physical sciences.

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

    Science.gov (United States)

    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.

  13. High regression rate hybrid rocket fuel grains with helical port structures

    Science.gov (United States)

    Walker, Sean D.

    Hybrid rockets are popular in the aerospace industry due to their storage safety, simplicity, and controllability during rocket motor burn. However, they produce fuel regression rates typically 25% lower than solid fuel motors of the same thrust level. These lowered regression rates produce unacceptably high oxidizer-to-fuel (O/F) ratios that produce a potential for motor instability, nozzle erosion, and reduced motor duty cycles. To achieve O/F ratios that produce acceptable combustion characteristics, traditional cylindrical fuel ports are fabricated with very long length-to-diameter ratios to increase the total burning area. These high aspect ratios produce further reduced fuel regression rate and thrust levels, poor volumetric efficiency, and a potential for lateral structural loading issues during high thrust burns. In place of traditional cylindrical fuel ports, it is proposed that by researching the effects of centrifugal flow patterns introduced by embedded helical fuel port structures, a significant increase in fuel regression rates can be observed. The benefits of increasing volumetric efficiencies by lengthening the internal flow path will also be observed. The mechanisms of this increased fuel regression rate are driven by enhancing surface skin friction and reducing the effect of boundary layer "blowing" to enhance convective heat transfer to the fuel surface. Preliminary results using additive manufacturing to fabricate hybrid rocket fuel grains from acrylonitrile-butadiene-styrene (ABS) with embedded helical fuel port structures have been obtained, with burn-rate amplifications up to 3.0x than that of cylindrical fuel ports.

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

    Science.gov (United States)

    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

  15. Autism's 'Worryingly' High Suicide Rates Spur Conference

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_165946.html Autism's 'Worryingly' High Suicide Rates Spur Conference Signs of ... News) -- High rates of suicide among people with autism are drawing specialists to a conference this week ...

  16. Burning rate characteristics of energetic CMDB propellants. Part 1. Combustion characteristics of basic propellant; Ko enerugi CMDB suishinyaku no nensho sokudo tokuse ( I ) - kihon suishin yaku no nensho tokusei -

    Energy Technology Data Exchange (ETDEWEB)

    Aoki, I. [Nissan Motor Co. Ltd. (Japan)

    1997-08-01

    In this study, the burning rate characteristics of double-base propellants as basic propellants of highly energetic CMDB (Composite Modified Double-Base) propellants are described. Namely, the relations between the amount of energy contained in the double-base propellants and the burning rate thereof are investigated by using the samples of the double-base propellants containing varied amount of energy. The following results are obtained. Final flame temperature, as a physical property of the propellant, is increased with the increase of explosion heat showing the amount of energy contained in the propellant. The higher the final flame temperature is, the higher the burning rate is. Although final flame does not occur even under a pressure of 0.35MPa if nickel is added, the burning rate of the propellant causing the final flame is unvaried from that of the propellant not causing the final flame. Dark zone temperature is getting higher with the rising of the final flame temperature, namely, the amount of energy contained in the propellant. 19 refs., 14 figs., 1 tab.

  17. Crude oil burning mechanisms

    DEFF Research Database (Denmark)

    van Gelderen, Laurens; Malmquist, L.M.V.; Jomaas, Grunde

    2015-01-01

    In order to improve predictions for the burning efficiency and the residue composition of in-situ burning of crude oil, the burning mechanism of crude oil was studied in relation to the composition of its hydrocarbon mixture, before, during and after the burning. The surface temperature, flame...... to the predictions of four conceptual models that describe the burning mechanism of multicomponent fuels. Based on the comparisons, hydrocarbon liquids were found to be best described by the Equilibrium Flash Vaporization model, showing a constant gas composition and gasification rate. The multicomponent fuels...... followed the diffusion-limited gasification model, showing a change in the hydrocarbon composition of the fuel and its evaporating gases, as well as a decreasing gasification rate, as the burning progressed. This burning mechanism implies that the residue composition and burning efficiency mainly depend...

  18. Comparison Between Surf and Multi-Shock Forest Fire High Explosive Burn Models

    Energy Technology Data Exchange (ETDEWEB)

    Greenfield, Nicholas Alexander [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-07-18

    PAGOSA1 has several different burn models used to model high explosive detonation. Two of these, Multi-Shock Forest Fire and Surf, are capable of modeling shock initiation. Accurately calculating shock initiation of a high explosive is important because it is a mechanism for detonation in many accident scenarios (i.e. fragment impact). Comparing the models to pop-plot data give confidence that the models are accurately calculating detonation or lack thereof. To compare the performance of these models, pop-plots2 were created from simulations where one two cm block of PBX 9502 collides with another block of PBX 9502.

  19. Extension and validation of the TRANSURANUS burn-up model for helium production in high burn-up LWR fuels

    Science.gov (United States)

    Botazzoli, Pietro; Luzzi, Lelio; Brémier, Stephane; Schubert, Arndt; Van Uffelen, Paul; Walker, Clive T.; Haeck, Wim; Goll, Wolfgang

    2011-12-01

    The TRANSURANUS burn-up model (TUBRNP) calculates the local concentration of the actinides, the main fission products, and 4He as a function of the radial position across a fuel rod. In this paper, the improvements in the helium production model as well as the extensions in the simulation of 238-242Pu, 241Am, 243Am and 242-245Cm isotopes are described. Experimental data used for the extended validation include new EPMA measurements of the local concentrations of Nd and Pu and recent SIMS measurements of the radial distributions of Pu, Am and Cm isotopes, both in a 3.5% enriched commercial PWR UO 2 fuel with a burn-up of 80 and 65 MWd/kgHM, respectively. Good agreement has been found between TUBRNP and the experimental data. The analysis has been complemented by detailed neutron transport calculations (VESTA code), and also revealed the need to update the branching ratio for the 241Am(n,γ) 242mAm reaction in typical PWR conditions.

  20. Burn Pits

    Science.gov (United States)

    ... Enter ZIP code here Enter ZIP code here Burn Pits Burn Pits Registry Studies Photo: U.S. Department ... the health of deployed Veterans. Health effects from burn pit smoke Toxins in burn pit smoke may ...

  1. Burn Institute

    Science.gov (United States)

    ... Now Help keep local seniors safe from fire! Burn Survivor Support If you are reading this, chances ... year – a burn injury. Learn more Fire and Burn Prevention Each year, the Burn Institute provides fire ...

  2. Analysis of predictor factors of limb amputation in patients with high-voltage electrical burns

    Directory of Open Access Journals (Sweden)

    Guillermo García Álvarez

    2015-09-01

    Full Text Available Background: Limb amputation is considered one of the most devastating consequences of electrical injury. Any factors that correlate with the degree of muscle damage can be used to predict the necessity of limb amputation. The aim of this study was to determine the factors that can be used to predict limb amputation in high-voltage electrically injured patients. Methods: Eighty-two high-voltage electrically injured patients were admitted to the Department of Plastic and Reconstructive Surgery and Burns of National Arzobispo Loayza Hospital on a 5 year period. A retrospective analysis of the possible related risk factors between amputation and non-amputation patients was performed. Results: A total of 68 patients were enrolled for analysis. Thirteen patients underwent limb amputations. Multivariate analysis of the risk factors between amputation and non-amputation groups showed statistical significance for first 24 hour creatine kinase-isoenzyme MB (CKMB level. A serum CK-MB level above 14,955 U/L predicted high risk of limb amputation with high specificity (84% and sensitivity (77%. Only one patient with a remarkable decrease of creatine kinase (CPKt and CK-MB levels after fasciotomy avoided a major limb amputation. Conclusion: Our results suggest that CPK-MB level is an independent factor for prediction of limb amputation in patients with high-voltage electrical burns. We suggest that the addition of CPK-MB evaluation to clinical symptom screening may be a valuable method for early detection of muscle damage.

  3. Thermodynamic analysis for high burn-up fuel internal chemistry. 2

    Energy Technology Data Exchange (ETDEWEB)

    Fuji, Kensho; Kyoh, Bunkei [Kinki Univ., Higashi-Osaka, Osaka (Japan)

    1998-09-01

    Thermodynamic calculations with the computer program SOLGASMIX-PV have been performed for the chemical states expected in irradiated fast breeder reactor (FBR) fuels containing transuranium (TRU) elements. The analysis shows that A (alkali and alkaline-earth)-molybdates exist, but neither A-uranates nor A-zirconates are formed in FBR fuel pellets irradiated to high burn-up. And increase of oxygen potential in irradiated FBR fuel is ascribed to growing amount of rare earth, noble metal and TRU elements. (author)

  4. High temperature corrosion by combustion gases produced by burning liquid fuels containing sulphur, sodium and vanadium.

    OpenAIRE

    Khan, Fazlur Rahman

    1980-01-01

    High temperature corrosion, at 730° C, by combustion gases produced by burning liquid fuels in a laboratory combustor has been investigated. A selected range of steels and alloys (mild steel, stainless steel type 347, Nimonic N90, N105, and IN657) have been tested in the combustion gases using fuels containing varying amounts of impurities in the range of 0 - 6% sulphur, 0 - 60 ppm sodium, and 0 - 300 ppm vanadium. On the basis of the comprehensive results a computer programme was written t...

  5. Review of Adult Electrical Burn Injury Outcomes Worldwide: An Analysis of Low-Voltage vs High-Voltage Electrical Injury.

    Science.gov (United States)

    Shih, Jessica G; Shahrokhi, Shahriar; Jeschke, Marc G

    The aims of this article are to review low-voltage vs high-voltage electrical burn complications in adults and to identify novel areas that are not recognized to improve outcomes. An extensive literature search on electrical burn injuries was performed using OVID MEDLINE, PubMed, and EMBASE databases from 1946 to 2015. Studies relating to outcomes of electrical injury in the adult population (≥18 years of age) were included in the study. Forty-one single-institution publications with a total of 5485 electrical injury patients were identified and included in the present study. Fourty-four percent of these patients were low-voltage injuries (LVIs), 38.3% high-voltage injuries (HVIs), and 43.7% with voltage not otherwise specified. Forty-four percentage of studies did not characterize outcomes according to LHIs vs HVIs. Reported outcomes include surgical, medical, posttraumatic, and others (long-term/psychological/rehabilitative), all of which report greater incidence rates in HVI than in LVI. Only two studies report on psychological outcomes such as posttraumatic stress disorder. Mortality rates from electrical injuries are 2.6% in LVI, 5.2% in HVI, and 3.7% in not otherwise specified. Coroner's reports revealed a ratio of 2.4:1 for deaths caused by LVI compared with HVI. HVIs lead to greater morbidity and mortality than LVIs. However, the results of the coroner's reports suggest that immediate mortality from LVI may be underestimated. Furthermore, on the basis of this analysis, we conclude that the majority of studies report electrical injury outcomes; however, the majority of them do not analyze complications by low vs high voltage and often lack long-term psychological and rehabilitation outcomes after electrical injury indicating that a variety of central aspects are not being evaluated or assessed.

  6. Burn-Up Determination by High Resolution Gamma Spectrometry: Axial and Diametral Scanning Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Forsyth, R.S.; Blackadder, W.H.; Ronqvist, N.

    1967-02-15

    In the gamma spectrometric determination of burn-up the use of a single fission product as a monitor of the specimen fission rate is subject to errors caused by activity saturation or, in certain cases, fission product migration. Results are presented of experiments in which all the resolvable gamma peaks in the fission product spectrum have been used to calculate the fission rate; these results form a pattern which reflect errors in the literature values of the gamma branching ratios, fission yields etc., and also represent a series of empirical correction factors. Axial and diametral scanning experiments on a long-irradiated low-enrichment fuel element are also described and demonstrate that it is possible to differentiate between fissions in U-235 and in Pu-239 respectively by means of the ratios of the Ru-106 activity to the activities of the other fission products.

  7. Chronic arsenic poisoning from burning high-arsenic-containing coal in Guizhou, China

    Energy Technology Data Exchange (ETDEWEB)

    Liu, J.; Zheng, B.S.; Aposhian, H.V.; Zhou, Y.S.; Chen, M.L.; Zhang, A.H.; Waalkes, M.P. [NIEHS, Research Triangle Park, NC (USA)

    2002-07-01

    Arsenic is an environmental hazard and the reduction of drinking water arsenic levels is under consideration. People are exposed to arsenic not only through drinking water but also through arsenic-contaminated air and food. Here the health effects of arsenic exposure from burning high arsenic-containing coal in Guizhou, China was investigated. Coal is burned inside the home in open pits for daily cooking and crop drying, producing a high concentration of arsenic in indoor air. Arsenic in the air coats and permeates food being dried producing high concentrations in food; however, arsenic concentrations in the drinking water are in the normal range. The estimated sources of total arsenic exposure in this area are from arsenic-contaminated food (50-80%), air (10-20%), water (1-5%), and direct contact in coal-mining workers (1%). At least 3,000 patients with arsenic poisoning were found in the Southwest Prefecture of Guizhou, and approximately 200,000 people are at risk for such over exposures. Skin lesions are common, including keratosis of the hands and feet, pigmentation on the trunk, skin ulceration, and skin cancers. Toxicities to internal organs, including lung dysfunction, neuropathy, and nephrotoxicity, are clinically evident. The prevalence of hepatomegaly was 20%, and cirrhosis, ascites, and liver cancer are the most serious outcomes of arsenic poisoning. The Chinese government and international organizations are attempting to improve the house conditions and the coal source, and thereby protect human health in this area.

  8. Behaviour of fission gas in the rim region of high burn-up UO 2 fuel pellets with particular reference to results from an XRF investigation

    Science.gov (United States)

    Mogensen, M.; Pearce, J. H.; Walker, C. T.

    1999-01-01

    XRF and EPMA results for retained xenon from Battelle's high burn-up effects program are re-evaluated. The data reviewed are from commercial low enriched BWR fuel with burn-ups of 44.8-54.9 GWd/tU and high enriched PWR fuel with burn-ups from 62.5 to 83.1 GWd/tU. It is found that the high burn-up structure penetrated much deeper than initially reported. The local burn-up threshold for the formation of the high burn-up structure in those fuels with grain sizes in the normal range lay between 60 and 75 GWd/tU. The high burn-up structure was not detected by EPMA in a fuel that had a grain size of 78 μm although the local burn-up at the pellet rim had exceeded 80 GWd/tU. It is concluded that fission gas had been released from the high burn-up structure in three PWR fuel sections with burn-ups of 70.4, 72.2 and 83.1 GWd/tU. In the rim region of the last two sections at the locations where XRF indicated gas release the local burn-up was higher than 75 GWd/tU.

  9. Burn-back Equations for High Volumetric Loading Single-grain Dual-thrust Rocket Propellant Configuration (Review Paper

    Directory of Open Access Journals (Sweden)

    Himanshu Shekhar

    2011-02-01

    Full Text Available Dual-thrust mode is adopted in solid propellant rocket propulsion through tailoring of burning area, nozzle, rocket motor chamber, propellant type, multiple propellant blocks. In the present study, mathematical formulation has been evolved for generation of burning surface area with web burnt for a simple central blind hole in a solid cylindrical propellant geometry with proper partial inhibition on external and lateral surfaces. The burn-back equation has been validated by static firing and parametric study was conducted to understand effect of various control geometrical parameters. The system is utilised for high volumetric loading, single propellant, single composition, single-chamber, single nozzle dual-thrust mode of burning profiles in rocket application.Defence Science Journal, 2011, 61(2, pp.165-170, DOI:http://dx.doi.org/10.14429/dsj.61.41

  10. Understanding High Rate Behavior Through Low Rate Analog

    Science.gov (United States)

    2014-04-28

    Dioh, N.N., et al., The High-Strain Rate Behavior of Polymers. Journal De Physique Iv, 1994. 4(C8): p. 119-124. 21. Dioh, N.N., P.S. Leevers, and J.G...constitutive response of polymeric materials as a function of temperature and strain rate. Journal De Physique Iv, 2003. 110: p. 27-32. 23. Brown, E.N...properties of polycarbonate under dynamic loading. Journal De Physique Iv, 2003. 110: p. 159-164. 56. Li, Z.H. and J. Lambros, Strain rate effects on the

  11. Evaluation of the U.S. Geological Survey Landsat burned area essential climate variable across the conterminous U.S. using commercial high-resolution imagery

    Science.gov (United States)

    Vanderhoof, Melanie; Brunner, Nicole M.; Beal, Yen-Ju G.; Hawbaker, Todd J.

    2017-01-01

    The U.S. Geological Survey has produced the Landsat Burned Area Essential Climate Variable (BAECV) product for the conterminous United States (CONUS), which provides wall-to-wall annual maps of burned area at 30 m resolution (1984–2015). Validation is a critical component in the generation of such remotely sensed products. Previous efforts to validate the BAECV relied on a reference dataset derived from Landsat, which was effective in evaluating the product across its timespan but did not allow for consideration of inaccuracies imposed by the Landsat sensor itself. In this effort, the BAECV was validated using 286 high-resolution images, collected from GeoEye-1, QuickBird-2, Worldview-2 and RapidEye satellites. A disproportionate sampling strategy was utilized to ensure enough burned area pixels were collected. Errors of omission and commission for burned area averaged 22 ± 4% and 48 ± 3%, respectively, across CONUS. Errors were lowest across the western U.S. The elevated error of commission relative to omission was largely driven by patterns in the Great Plains which saw low errors of omission (13 ± 13%) but high errors of commission (70 ± 5%) and potentially a region-growing function included in the BAECV algorithm. While the BAECV reliably detected agricultural fires in the Great Plains, it frequently mapped tilled areas or areas with low vegetation as burned. Landscape metrics were calculated for individual fire events to assess the influence of image resolution (2 m, 30 m and 500 m) on mapping fire heterogeneity. As the spatial detail of imagery increased, fire events were mapped in a patchier manner with greater patch and edge densities, and shape complexity, which can influence estimates of total greenhouse gas emissions and rates of vegetation recovery. The increasing number of satellites collecting high-resolution imagery and rapid improvements in the frequency with which imagery is being collected means greater opportunities to utilize these sources

  12. Possibility of formation of functional dependences of homogeneous and heterogeneous systems burning rate on different factors on the base of precised theory of Mallard and Le Chatelier

    Energy Technology Data Exchange (ETDEWEB)

    Kashporov, L.Y.; Sheludyak, Y.E.; Obeziaev, N.V.; Raspopin, A.G. [Russian Corporation, Metalkhim, Moscow (Russian Federation)

    1996-12-31

    In this work it is shown that the hypothesis of Mallard and Le Chatelier about the existence of critical temperature T{sub c} in the stationary burning wave, which is analogous to the temperature of ignition, is well-grounded physically. The equation which comes out from this hypothesis allows to calculate the functional dependences of the burning rate on pressure P and initial temperature T{sub o} - for homogeneous systems and on the other factors influencing the burning rate (porosity M, mean particle sizes of oxidant d{sub o} and metal d{sub m} and so on) - for condensed systems. Functional dependences u(P, T{sub o}) for methane/air mixture, hexogen, nitroglycerin powder have been calculated, and for pyrotechnics composition Mg + NaNO{sub 3} the dependence u(T{sub o}, M, d{sub o}, d{sub m}) at the atmospheric pressure has been obtained. (authors) 15 refs.

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

    Science.gov (United States)

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

    Directory of Open Access Journals (Sweden)

    D. W. T. Griffith

    2013-02-01

    Full Text Available 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

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

    Directory of Open Access Journals (Sweden)

    D. W. T. Griffith

    2012-09-01

    Full Text Available 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

  16. esearch and Application of Burned Microporous High Alumian—Graphite(Al/C) Brick in Blast Furnace

    Institute of Scientific and Technical Information of China (English)

    ZHANXiaoming; SONGMusen

    1999-01-01

    This paper inroduces the research background,technology,product property and application of burned microporous high alumina-graphite brick (Al2O3-C brick) used in blast furnace,The difference of property between Al2O3-C brick and other blast furnace refractories is discussed .The results of simulative tests show that ,Al2O3-C brick has good alkali resistance,slag resistance,thermal shock resistance,oxidation resistance,high thermal conductivity,low permeability and low solubility in molten iron,The brick with micropores of average radius less than 1μm has been successively applied to fourteen blast furnaces, the lining life of the brick is almost as long as that of Si3N4 bonded SiC brick Al2O3-C brick will be widely used in lower stack ,belly,bosh and hearth in the future.

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

    Science.gov (United States)

    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.

  18. Pyogenic Arthritis of the Ankle Joint Following a High-Voltage Electrical Burn in the Lower Extremity: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kuk Seon; Lee, Gyung Kyu; Kang, Ik Won; Hwang, Dae Hyun; Lee, Eil Seong; Min, Seon Jung; Han, You Mie [Dept. of Radiology, Hangang Scared Heart Hospital, Hallym University College of Medicine, Seoul (Korea, Republic of); Lee, Eil Seong [Dept.of Radiology, Gyeongju Hospital, Dongguk University College of Medicine, Gyeongju (Korea, Republic of)

    2011-04-15

    A high-voltage electrical burn caused extensive deep muscle injuries beneath a relatively small skin wound at the contact point. Hidden, undetected deep muscle injuries have a tendency for progressive tissue necrosis, which can lead to major amputations or sepsis. The radiologic features of this rare, sometimes life-threatening injury have occasionally been described in the literature. However, to the best of our knowledge, there have been no reports on a case of pyogenic arthritis of the ankle joint following a high-voltage electrical burn involving the lower extremity. We report a case of the pyogenic arthritis of the ankle joint following a high-voltage electrical burn involving the lower extremity.

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

    Science.gov (United States)

    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.

  20. Development of a method for xenon determination in the microstructure of high burn-up nuclear fuel[Dissertation 17527

    Energy Technology Data Exchange (ETDEWEB)

    Horvath, M. I

    2008-07-01

    , relevant Xe isotope concentrations in fission gas inclusions have not been reported yet. The aim of this work was focused on quantitative analysis of Xe isotope concentrations in inclusions of high burn-up samples to determine gas pressures within fuel pores. Therefore, various calibration strategies were studied in great detail. The investigation of Xe-implantation showed that the uncertainties in Xe ion implantation are too high to produce suitable Xe-implanted standard materials. The generation of Xe-bubbles in Plexiglass was also investigated and Xe inclusions of different bubble sizes were generated. However, the size determinations of the inclusions, the opening and possible gas losses through the Plexiglass were factors preventing accurate Xe quantification. The use of direct Xe gas injection was considered as a suitable strategy for establishing calibration curves. The Xe response was studied in dependence on gas concentration, gas volume and presence or absence of matrix in the ICP (Inductively Coupled Plasma). To investigate the ionization behavior of Xe in the ICP, the ablation behavior of ZrO{sub 2} and UO{sub 2} was determined in dependence on different wavelengths (266 nm, 193 nm), crater diameters, repetition rates and carrier gases (Ar, He). The mass ablated per laser pulse was very similar for the two matrices. The simultaneous introduction of matrix and gas into the ICP showed insignificant matrix effects. Even the absence of matrix effects was shown, filtering of the matrix before entering the plasma was evaluated to be crucial. Applying a filter leads to a complete gas/solid separation and opens access to the matrix interfering {sup 134}Xe and {sup 136}Xe isotopes. Thus, calibration gas addition in combination with an aerosol filter was the key strategy for quantification of Xe fission gas production in high burn-up fuel samples. Gas addition in volumes of 1 to 100 {mu}l and at a concentration of 20 and 200 {mu}g/g provided linear calibration curves

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

    Energy Technology Data Exchange (ETDEWEB)

    Lamia, L. [Dipartimento di Fisica e Astronomia, Università degli Studi di Catania, Catania (Italy); Spitaleri, C. [Dipartimento di Fisica e Astronomia, Università degli Studi di Catania, Catania, Italy and INFN-Laboratori Nazionali del Sud, Catania (Italy); La Cognata, M.; Palmerini, S.; Sergi, M. L. [INFN-Laboratori Nazionali del Sud, Catania (Italy); Puglia, S. M. R. [INFN-Laboratori Nazionali del Sud, Catania, Italy and Dipartimento di Fisica e Astronomia, Università degli Studi di Catania, Catania (Italy)

    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.

  2. Systematic Uncertainties in High-Rate Germanium Data

    Energy Technology Data Exchange (ETDEWEB)

    Gilbert, Andrew J.; Fast, James E.; Fulsom, Bryan G.; Pitts, William K.; VanDevender, Brent A.; Wood, Lynn S.

    2016-10-06

    For many nuclear material safeguards inspections, spectroscopic gamma detectors are required which can achieve high event rates (in excess of 10^6 s^-1) while maintaining very good energy resolution for discrimination of neighboring gamma signatures in complex backgrounds. Such spectra can be useful for non-destructive assay (NDA) of spent nuclear fuel with long cooling times, which contains many potentially useful low-rate gamma lines, e.g., Cs-134, in the presence of a few dominating gamma lines, such as Cs-137. Detectors in use typically sacrifice energy resolution for count rate, e.g., LaBr3, or visa versa, e.g., CdZnTe. In contrast, we anticipate that beginning with a detector with high energy resolution, e.g., high-purity germanium (HPGe), and adapting the data acquisition for high throughput will be able to achieve the goals of the ideal detector. In this work, we present quantification of Cs-134 and Cs-137 activities, useful for fuel burn-up quantification, in fuel that has been cooling for 22.3 years. A segmented, planar HPGe detector is used for this inspection, which has been adapted for a high-rate throughput in excess of 500k counts/s. Using a very-high-statistic spectrum of 2.4*10^11 counts, isotope activities can be determined with very low statistical uncertainty. However, it is determined that systematic uncertainties dominate in such a data set, e.g., the uncertainty in the pulse line shape. This spectrum offers a unique opportunity to quantify this uncertainty and subsequently determine required counting times for given precision on values of interest.

  3. The visual analogue thermometer and the graphic numeric rating scale: a comparison of self-report instruments for pain measurement in adults with burns.

    Science.gov (United States)

    de Jong, A E E; Bremer, M; Hofland, H W C; Schuurmans, M J; Middelkoop, E; van Loey, N E E

    2015-03-01

    To evaluate the adequacy of pain management in burn care, pain measurement is essential. The visual analogue thermometer (VAT) and graphic numeric rating scale (GNRS) are frequently used self-report instruments for burn pain. To legitimise their interchangeable use in research and practice, we aimed to compare self-reports obtained by the VAT and GNRS, the ability of the scales to differentiate background from procedural pain, and to compare potential cutpoints. Adults with acute burns (N=319) participated in the study (67% male, mean age 40.3 years (SD 16), mean TBSA 9.9% (SD 10.4). Correlation coefficients between VAT and GNRS were 0.64 and 0.55 for, respectively, morning and afternoon background pain and 0.51 for procedural pain (pscales could differentiate background from procedural pain: procedural pain was higher (pscales. The results suggest that the instruments cannot be used interchangeably without taking their differences into account.

  4. Erosive Burning Study Utilizing Ultrasonic Measurement Techniques

    Science.gov (United States)

    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.

  5. Implications of high altitude desert dust transport from Western Sahara to Nile Delta during biomass burning season.

    Science.gov (United States)

    Prasad, Anup K; El-Askary, Hesham; Kafatos, Menas

    2010-11-01

    The air over major cities and rural regions of the Nile Delta is highly polluted during autumn which is the biomass burning season, locally known as black cloud. Previous studies have attributed the increased pollution levels during the black cloud season to the biomass or open burning of agricultural waste, vehicular, industrial emissions, and secondary aerosols. However, new multi-sensor observations (column and vertical profiles) from satellites, dust transport models and associated meteorology present a different picture of the autumn pollution. Here we show, for the first time, the evidence of long range transport of dust at high altitude (2.5-6 km) from Western Sahara and its deposition over the Nile Delta region unlike current Models. The desert dust is found to be a major contributor to the local air quality which was previously considered to be due to pollution from biomass burning enhanced by the dominant northerly winds coming from Europe.

  6. High frame rate synthetic aperture duplex imaging

    DEFF Research Database (Denmark)

    Stuart, Matthias Bo; Tomov, Borislav Gueorguiev; Pihl, Michael Johannes

    2013-01-01

    aperture flow imaging as demonstrated in this paper. Synthetic aperture, directional beamforming, and cross-correlation are used to produce B-mode and vector velocity images at high frame rates. The frame rate equals the effective pulse repetition frequency of each imaging mode. Emissions for making the B...

  7. High-Rate Receiver Design Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose an initial architectural and preliminary hardware design study for a high-rate receiver capable of decoding modulation suites specified by CCSDS 413.0-G-1...

  8. Ambiguities of the Rate of Oxygen Formation During Stellar Helium Burning in the 12C(a,g) Reaction

    CERN Document Server

    Gai, Moshe

    2013-01-01

    The rate of oxygen formation determines the C/O ratio during stellar helium burning. It is the single most important nuclear input of stellar evolution theory including the evolution of Type II and Type Ia supernova. Yet the low energy cross section of the fusion of 4He + 12C denoted as the 12C(a,g)16O reaction still remains uncertain after forty years of extensive work. We analyze and critically review the most recent measurements of complete angular distributions of the outgoing gamma-rays at very low energies (Ecm > 1.0 MeV). Our analysis of the angular distribution measured with the EUROGAM/GANDI arrays lead us to conclude considerably larger error bars than published hence they are excluded from the current sample of "world data". We show that the current sample of "world data" of the measured E2 cross section factors below 1.7 MeV cluster to two distinct groups that lead to two distinct extrapolations of SE2(300) ~ 60 or ~ 154 keVb. We point to a much neglected discrepancy between the measured E1-E2 pha...

  9. Record high peaks in PCB concentrations in the Arctic atmosphere due to long-range transport of biomass burning emissions

    Directory of Open Access Journals (Sweden)

    S. Eckhardt

    2007-05-01

    Full Text Available Soils and forests in the boreal region of the northern hemisphere are recognised as having a large capacity for storing air-borne Persistent Organic Pollutants (POPs, such as the polychlorinated biphenyls (PCBs. Following reductions of primary emissions of various legacy POPs, there is an increasing interest and debate about the relative importance of secondary re-emissions on the atmospheric levels of POPs. In spring of 2006, biomass burning emissions from agricultural fires in Eastern Europe were transported to the Zeppelin station on Svalbard, where record-high levels of many air pollutants were recorded (Stohl et al., 2007. Here we report on the extremely high concentrations of PCBs that were also measured during this period. 21 out of 32 PCB congeners were enhanced by more than two standard deviations above the long-term mean concentrations. In July 2004, about 5.8 million hectare of boreal forest burned in North America, emitting a pollution plume which reached the Zeppelin station after a travel time of 3–4 weeks (Stohl et al., 2006. Again, 12 PCB congeners were elevated above the long-term mean by more than two standard deviations, with the less chlorinated congeners being most strongly affected. We propose that these abnormally high concentrations were caused by biomass burning emissions. Based on enhancement ratios with carbon monoxide and known emissions factors for this species, we estimate that 130 and 66 μg PCBs were released per kilogram dry matter burned, respectively. To our knowledge, this is the first study relating atmospheric PCB enhancements with biomass burning. The strong effects on observed concentrations far away from the sources, suggest that biomass burning is an important source of PCBs for the atmosphere.

  10. Transmutation Analysis of Enriched Uranium and Deep Burn High Temperature Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Michael A. Pope

    2012-07-01

    High temperature reactors (HTRs) have been under consideration for production of electricity, process heat, and for destruction of transuranics for decades. As part of the transmutation analysis efforts within the Fuel Cycle Research and Development (FCR&D) campaign, a need was identified for detailed discharge isotopics from HTRs for use in the VISION code. A conventional HTR using enriched uranium in UCO fuel was modeled having discharge burnup of 120 GWd/MTiHM. Also, a deep burn HTR (DB-HTR) was modeled burning transuranic (TRU)-only TRU-O2 fuel to a discharge burnup of 648 GWd/MTiHM. For each of these cases, unit cell depletion calculations were performed with SCALE/TRITON. Unit cells were used to perform this analysis using SCALE 6.1. Because of the long mean free paths (and migration lengths) of neutrons in HTRs, using a unit cell to represent a whole core can be non-trivial. The sizes of these cells were first set by using Serpent calculations to match a spectral index between unit cell and whole core domains. In the case of the DB-HTR, the unit cell which was arrived at in this way conserved the ratio of fuel to moderator found in a single block of fuel. In the conventional HTR case, a larger moderator-to-fuel ratio than that of a single block was needed to simulate the whole core spectrum. Discharge isotopics (for 500 nuclides) and one-group cross-sections (for 1022 nuclides) were delivered to the transmutation analysis team. This report provides documentation for these calculations. In addition to the discharge isotopics, one-group cross-sections were provided for the full list of 1022 nuclides tracked in the transmutation library.

  11. Factors associated with mortality in adult hospitalized burn patients in Tehran.

    Science.gov (United States)

    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.

  12. Resuscitation after severe burn injury using high-dose ascorbic acid: a retrospective review.

    Science.gov (United States)

    Kahn, Steven Alexander; Beers, Ryan J; Lentz, Christopher W

    2011-01-01

    Resuscitation of burn victims with high-dose ascorbic acid (vitamin C [VC]) was reported in Japan in the year 2000. Benefits of VC include reduction in fluid requirements, resulting in less tissue edema and body weight gain. In turn, these patients suffer less respiratory impairment and reduced requirement for mechanical ventilation. Despite these results, few burn centers resuscitate patients with VC in fear that it may increase the risk of renal failure. A retrospective review of 40 patients with greater than 20% TBSA between 2007 and 2009 was performed. Patients were divided into two groups: one received only lactated Ringer's (LR) solution and another received LR solution plus 66 mg/kg/hr VC. Both groups were resuscitated with the Parkland formula to maintain stable hemodynamics and adequate urine output (>0.5 ml/kg/hr). Patients with >10-hour delay in transfer to the burn center were excluded. Data collected included age, gender, weight, %TBSA, fluid administered in the first 24 hours, urine output in the first 24 hours, and Acute Physiology and Chronic Health Evaluation II score. PaO2 in millimeters mercury:%FIO2 ratio and positive end-expiratory pressure were measured at 12-hour intervals, and hematocrit was measured at 6-hour intervals. Comorbidities, mortality, pneumonia, fasciotomies, and renal failure were also noted. After 7 patients were excluded, 17 patients were included in the VC group and 16 in the LR group. VC and LR were matched for age (42 ± 16 years vs 50 ± 20 years, P = .2), burn size (45 ± 21%TBSA vs 39 ± 15%TBSA, P = .45), Acute Physiology and Chronic Health Evaluation II (17 ± 7 vs 18 ± 8, P = .8), and gender. Fluid requirements in the first 24 hours were 5.3 ± 1 ml/kg/%TBSA for VC and 7.1 ± 1 ml/kg/%TBSA for LR (P < .05). Urine output was 1.5 ± 0.4 ml/kg/hr for VC and 1 ± 0.5 ml/kg/hr for LR (P < .05). Vasopressors were needed in four VC patients and nine LR patients (P = .07). VC patients required vasopressors to maintain mean

  13. Understanding High Saving Rate in China

    Institute of Scientific and Technical Information of China (English)

    Xinhua He; Yongfu Cao

    2007-01-01

    This paper presents a detailed analysis of the Chinese saving rate based on the flow of funds data. It finds that the most widely adopted view of precautionary saving, which is regarded as the top reason for maintaining a high saving rate in China, is misleading because this conclusion is drawn from the household survey data. In fact, the household saving rate has declined dramatically since the mid-1990s, as is observed from the flow of funds framework.The high national saving rate is attributed to the increasing shares of both government and corporation disposable incomes. Insufficient consumption demand is caused by the persistent decrease in percentage share of household to national disposable income. Governmentdirected income redistribution urgently needs to be improved to accelerate consumption,which in turn would make the Chinese economy less investment-led and help to reduce the current account surplus.

  14. A high-strain-rate superplastic ceramic.

    Science.gov (United States)

    Kim, B N; Hiraga, K; Morita, K; Sakka, Y

    2001-09-20

    High-strain-rate superplasticity describes the ability of a material to sustain large plastic deformation in tension at high strain rates of the order of 10-2 to 10-1 s-1 and is of great technological interest for the shape-forming of engineering materials. High-strain-rate superplasticity has been observed in aluminium-based and magnesium-based alloys. But for ceramic materials, superplastic deformation has been restricted to low strain rates of the order of 10-5 to 10-4 s-1 for most oxides and nitrides with the presence of intergranular cavities leading to premature failure. Here we show that a composite ceramic material consisting of tetragonal zirconium oxide, magnesium aluminate spinel and alpha-alumina phases exhibits superplasticity at strain rates up to 1 s-1. The composite also exhibits a large tensile elongation, exceeding 1,050 per cent for a strain rate of 0.4 s-1. The tensile flow behaviour and deformed microstructure of the material indicate that superplasticity is due to a combination of limited grain growth in the constitutive phases and the intervention of dislocation-induced plasticity in the zirconium oxide phase. We suggest that the present results hold promise for the application of shape-forming technologies to ceramic materials.

  15. Electrorheological Effects at High Shear Rate

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Much attention has been given to electrorheological (ER) fluids because of the ER effect, which has been described by a large number of researchers as a notable increase in the apparent viscosity of a fluid upon the application of an electric field. The description of ER effects is, however, not accurate at high shear rates. To clarify the discrepancy, we analyze and compute the apparent viscosity as a function of shear rate for ER fluid flow between rotating coaxial cylinders in the presence of an electric field. The theoretical predictions show that the increase of electric intensity contributes little to the apparent viscosity enhancement at high shear rates, while ER effects for ER fluids with a higher polarization rate still exist and ER devices possess controllability in this regime. Description of the ER effect by the apparent viscosity leads to an unrealistic conclusion that ER effects disappear at high shear rates, because the apparent viscosity of ER fluids approaches the value for Newtonian fluids. Therefore, it is concluded that the proper description of ER effects, i.e., one that holds uniformly for any strain rate when ER effects exist, is manifested by a remarkable increase in the extra stress rather than in the apparent viscosity of ER fluids.

  16. Thrombus Formation at High Shear Rates.

    Science.gov (United States)

    Casa, Lauren D C; Ku, David N

    2017-06-21

    The final common pathway in myocardial infarction and ischemic stroke is occlusion of blood flow from a thrombus forming under high shear rates in arteries. A high-shear thrombus forms rapidly and is distinct from the slow formation of coagulation that occurs in stagnant blood. Thrombosis at high shear rates depends primarily on the long protein von Willebrand factor (vWF) and platelets, with hemodynamics playing an important role in each stage of thrombus formation, including vWF binding, platelet adhesion, platelet activation, and rapid thrombus growth. The prediction of high-shear thrombosis is a major area of biofluid mechanics in which point-of-care testing and computational modeling are promising future directions for clinically relevant research. Further research in this area will enable identification of patients at high risk for arterial thrombosis, improve prevention and treatment based on shear-dependent biological mechanisms, and improve blood-contacting device design to reduce thrombosis risk.

  17. High Strain Rate Characterisation of Composite Materials

    DEFF Research Database (Denmark)

    Eriksen, Rasmus Normann Wilken

    The high strain rate characterisation of FRP materials present the experimenter with a new set of challenges in obtaining valid experimental data. These challenges were addressed in this work with basis in classic wave theory. The stress equilibrium process for linear elastic materials, as fibre...... a linear elastic specimen to reach a state of constant strain rate before fracture. This was in contrast to ductile materials, which are widely tested with for the High-speed servohydraulic test machine. The development of the analysis and the interpretation of the results, were based on the experience...

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

    Directory of Open Access Journals (Sweden)

    Shu-Sen Chang

    2014-04-01

    Full Text Available 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

  19. TEM Characterization of High Burn-up Microstructure of U-7Mo Alloy

    Energy Technology Data Exchange (ETDEWEB)

    Jian Gan; Brandon Miller; Dennis Keiser; Adam Robinson; James Madden; Pavel Medvedev; Daniel Wachs

    2014-04-01

    As an essential part of global nuclear non-proliferation effort, the RERTR program is developing low enriched U-Mo fuels (< 20% U-235) for use in research and test reactors that currently employ highly enriched uranium fuels. One type of fuel being developed is a dispersion fuel plate comprised of U-7Mo particles dispersed in Al alloy matrix. Recent TEM characterizations of the ATR irradiated U-7Mo dispersion fuel plates include the samples with a local fission densities of 4.5, 5.2, 5.6 and 6.3 E+21 fissions/cm3 and irradiation temperatures of 101-136?C. The development of the irradiated microstructure of the U-7Mo fuel particles consists of fission gas bubble superlattice, large gas bubbles, solid fission product precipitates and their association to the large gas bubbles, grain subdivision to tens or hundreds of nanometer size, collapse of bubble superlattice, and amorphisation. This presentation will describe the observed microstructures specifically focusing on the U-7Mo fuel particles. The impact of the observed microstructure on the fuel performance and the comparison of the relevant features with that of the high burn-up UO2 fuels will be discussed.

  20. Picosecond pulses of variable duration from a high-power passively mode-locked Nd:YVO(4) laser free of spatial hole burning.

    Science.gov (United States)

    Nadeau, Marie-Christine; Petit, Stéphane; Balcou, Philippe; Czarny, Romain; Montant, Sébastien; Simon-Boisson, Christophe

    2010-05-15

    We report on a high-power passively mode-locked TEM(00)Nd:YVO(4) oscillator, 888 nm diode-pumped, with pulse durations adjustable between 46 ps and 12 ps. The duration tunability was obtained by varying the output coupler (OC) transmission while avoiding resorting to spatial hole burning (SHB) for pulse shortening. At a repetition rate of 91 MHz and for an output power ranging from 15 Wto45 W, we produced SHB-free 12-ps-to32-ps-long pulses. Within this range of power, these are the shortest pulse durations obtained directly from Nd:YVO(4) oscillators.

  1. High Resolution Measurement of the Glycolytic Rate

    Science.gov (United States)

    Bittner, Carla X.; Loaiza, Anitsi; Ruminot, Iván; Larenas, Valeria; Sotelo-Hitschfeld, Tamara; Gutiérrez, Robin; Córdova, Alex; Valdebenito, Rocío; Frommer, Wolf B.; Barros, L. Felipe

    2010-01-01

    The glycolytic rate is sensitive to physiological activity, hormones, stress, aging, and malignant transformation. Standard techniques to measure the glycolytic rate are based on radioactive isotopes, are not able to resolve single cells and have poor temporal resolution, limitations that hamper the study of energy metabolism in the brain and other organs. A new method is described in this article, which makes use of a recently developed FRET glucose nanosensor to measure the rate of glycolysis in single cells with high temporal resolution. Used in cultured astrocytes, the method showed for the first time that glycolysis can be activated within seconds by a combination of glutamate and K+, supporting a role for astrocytes in neurometabolic and neurovascular coupling in the brain. It was also possible to make a direct comparison of metabolism in neurons and astrocytes lying in close proximity, paving the way to a high-resolution characterization of brain energy metabolism. Single-cell glycolytic rates were also measured in fibroblasts, adipocytes, myoblasts, and tumor cells, showing higher rates for undifferentiated cells and significant metabolic heterogeneity within cell types. This method should facilitate the investigation of tissue metabolism at the single-cell level and is readily adaptable for high-throughput analysis. PMID:20890447

  2. High resolution measurement of the glycolytic rate

    Directory of Open Access Journals (Sweden)

    Carla X Bittner

    2010-09-01

    Full Text Available The glycolytic rate is sensitive to physiological activity, hormones, stress, aging and malignant transformation. Standard techniques to measure the glycolytic rate are based on radioactive isotopes, are not able to resolve single cells and have poor temporal resolution, limitations that hamper the study of energy metabolism in the brain and other organs. A new method is described in this article, which makes use of a recently-developed FRET glucose nanosensor to measure the rate of glycolysis in single cells with high temporal resolution. Used in cultured astrocytes, the method showed for the first time that glycolysis can be activated within seconds by a combination of glutamate and K+, supporting a role for astrocytes in neurometabolic and neurovascular coupling in the brain. It was also possible to make a direct comparison of metabolism in neurons and astrocytes lying in close proximity, paving the way to a high-resolution characterization of brain energy metabolism. Single-cell glycolytic rates were also measured in fibroblasts, adipocytes, myoblasts and tumor cells, showing higher rates for undifferentiated cells and significant metabolic heterogeneity within cell types. This method should facilitate the investigation of tissue metabolism at the single-cell level and is readily adaptable for high-throughput analysis.

  3. High rate, high reliability Li/SO2 cells

    Science.gov (United States)

    Chireau, R.

    1982-03-01

    The use of the lithium/sulfur dioxide system for aerospace applications is discussed. The high rate density in the system is compared to some primary systems: mercury zinc, silver zinc, and magnesium oxide. Estimates are provided of the storage life and shelf life of typical lithium sulfur batteries. The design of lithium cells is presented and criteria are given for improving the output of cells in order to achieve high rate and high reliability.

  4. A high-resolution and multi-year emissions inventory for biomass burning in Southeast Asia during 2001-2010

    Science.gov (United States)

    Shi, Yusheng; Yamaguchi, Yasushi

    2014-12-01

    Biomass burning (BB) emissions from forest fires, agricultural waste burning, and peatland combustion contain large amounts of greenhouse gases (e.g., CO2, CH4, and N2O), which significantly impact ecosystem productivity, global atmospheric chemistry, and climate change. With the help of recently released satellite products, biomass density based on satellite and observation data, and spatiotemporal variable combustion factors, this study developed a new high-resolution and multi-year emissions inventory for BB in Southeast Asia (SEA) during 2001-2010. The 1-km grid was effective for quantifying emissions from small-sized fires that were frequently misinterpreted by coarse grid data due to their large smoothed pixels. The average annual BB emissions in SEA during 2001-2010 were 277 Gg SO2, 1125 Gg NOx, 55,388 Gg CO, 3831 Gg NMVOC, 553 Gg NH3, 324 Gg BC, 2406 Gg OC, 3832 Gg CH4, 817,809 Gg CO2, and 99 Gg N2O. Emissions were high in western Myanmar, Northern Thailand, eastern Cambodia, northern Laos, and South Sumatra and South Kalimantan of Indonesia. Emissions from forest burning were the dominant contributor to the total emissions among all land types. The spatial pattern of BB emissions was consistent with that of the burned areas. In addition, BB emissions exhibited similar temporal trends from 2001 to 2010, with strong interannual and intraannual variability. Interannual and intraannual emission peaks were seen during 2004, 2007, 2010, and January-March and August-October, respectively.

  5. Epidemiology of hospitalized burn patients in Taleghani Hospital during 2003-2007.

    Science.gov (United States)

    Ekrami, A; Hemadi, A; Latifi, M; Kalantar, E

    2010-01-01

    The objective of this study was to describe the epidemiology of burn injuries refered to Taleghani Burn hospital, Ahvaz and to provide information necessary for planning and implementing an effective prevention program. The medical records of 6082 consecutive admissions for burn injury treated at Taleghani burn hospital over a five-year period (August 2003 to August 2007) were reviewed. Our results shows that hospital stay in female was significantly longer than in male (p hospital stay and %TBSA (chi2, p patients, 486 deaths were recorded. The overall mortality rate of hospitalized burns patients was 8%. Mortality rate in female was higher than in male (p hospitalized burn patients at Taleghani burn hospital. Prevention programs for reducing the risk of burns are needed. Furthermore, high %TBSA and mortality and the presence of multi-drugs resistant bacteria are major worrying problems in our hospital (Tab. 5, Fig. 2, Ref. 27).

  6. High Rate Performing Li-ion Battery

    Science.gov (United States)

    2015-02-09

    permeable to lithium ions and efficient in transferring the electrons into/from the LVP surface to the corresponding current collector. a) b) c) d) e...PO4)3/C for High Rate Lithium-ion Battery Applications”, Lee Hwang Sheng, Nail Suleimanov, Vishwanathan Ramar, Mangayarkarasi Murugan, Kuppan

  7. [Hopes of high dose-rate radiotherapy].

    Science.gov (United States)

    Fouillade, Charles; Favaudon, Vincent; Vozenin, Marie-Catherine; Romeo, Paul-Henri; Bourhis, Jean; Verrelle, Pierre; Devauchelle, Patrick; Patriarca, Annalisa; Heinrich, Sophie; Mazal, Alejandro; Dutreix, Marie

    2017-04-01

    In this review, we present the synthesis of the newly acquired knowledge concerning high dose-rate irradiations and the hopes that these new radiotherapy modalities give rise to. The results were presented at a recent symposium on the subject. Copyright © 2017. Published by Elsevier Masson SAS.

  8. Understanding High School Graduation Rates in Arizona

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  9. Understanding High School Graduation Rates in Delaware

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  10. Understanding High School Graduation Rates in Idaho

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  11. Understanding High School Graduation Rates in Illinois

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  12. Understanding High School Graduation Rates in Massachusetts

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  13. Understanding High School Graduation Rates in Pennsylvania

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  14. Understanding High School Graduation Rates in Minnesota

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  15. Understanding High School Graduation Rates in Kentucky

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  16. Understanding High School Graduation Rates in Maryland

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  17. Understanding High School Graduation Rates in Wisconsin

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  18. Understanding High School Graduation Rates in Wyoming

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  19. Understanding High School Graduation Rates in Alaska

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  20. Understanding High School Graduation Rates in Oklahoma

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  1. Understanding High School Graduation Rates in Tennessee

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  2. Understanding High School Graduation Rates in Georgia

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  3. Understanding High School Graduation Rates in Iowa

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  4. Understanding High School Graduation Rates in Nevada

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  5. Understanding High School Graduation Rates in Texas

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  6. Understanding High School Graduation Rates in Florida

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  7. Understanding High School Graduation Rates in Nebraska

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  8. Understanding High School Graduation Rates in Oregon

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  9. Understanding High School Graduation Rates in Kansas

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  10. Understanding High School Graduation Rates in Virginia

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  11. Understanding High School Graduation Rates in Connecticut

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  12. Understanding High School Graduation Rates in Hawaii

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  13. Understanding High School Graduation Rates in Vermont

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  14. Understanding High School Graduation Rates in Mississippi

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  15. Understanding High School Graduation Rates in California

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  16. Understanding High School Graduation Rates in Ohio

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  17. Understanding High School Graduation Rates in Montana

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  18. Understanding High School Graduation Rates in Maine

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  19. Understanding High School Graduation Rates in Washington

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  20. Understanding High School Graduation Rates in Louisiana

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  1. Understanding High School Graduation Rates in Colorado

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  2. Understanding High School Graduation Rates in Michigan

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  3. Understanding High School Graduation Rates in Indiana

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  4. Understanding High School Graduation Rates in Utah

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  5. Understanding High School Graduation Rates in Alabama

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  6. Understanding High School Graduation Rates in Arkansas

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  7. Understanding High School Graduation Rates in Missouri

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  8. Burn care in South Africa: a micro cosmos of Africa.

    Science.gov (United States)

    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.

  9. Probability and volume of potential postwildfire debris flows in the 2012 High Park Burn Area near Fort Collins, Colorado

    Science.gov (United States)

    Verdin, Kristine L.; Dupree, Jean A.; Elliott, John G.

    2012-01-01

    This report presents a preliminary emergency assessment of the debris-flow hazards from drainage basins burned by the 2012 High Park fire near Fort Collins in Larimer County, Colorado. Empirical models derived from statistical evaluation of data collected from recently burned basins throughout the intermountain western United States were used to estimate the probability of debris-flow occurrence and volume of debris flows along the burned area drainage network and to estimate the same for 44 selected drainage basins along State Highway 14 and the perimeter of the burned area. Input data for the models included topographic parameters, soil characteristics, burn severity, and rainfall totals and intensities for a (1) 2-year-recurrence, 1-hour-duration rainfall (25 millimeters); (2) 10-year-recurrence, 1-hour-duration rainfall (43 millimeters); and (3) 25-year-recurrence, 1-hour-duration rainfall (51 millimeters). Estimated debris-flow probabilities along the drainage network and throughout the drainage basins of interest ranged from 1 to 84 percent in response to the 2-year-recurrence, 1-hour-duration rainfall; from 2 to 95 percent in response to the 10-year-recurrence, 1-hour-duration rainfall; and from 3 to 97 in response to the 25-year-recurrence, 1-hour-duration rainfall. Basins and drainage networks with the highest probabilities tended to be those on the eastern edge of the burn area where soils have relatively high clay contents and gradients are steep. Estimated debris-flow volumes range from a low of 1,600 cubic meters to a high of greater than 100,000 cubic meters. Estimated debris-flow volumes increase with basin size and distance along the drainage network, but some smaller drainages were also predicted to produce substantial volumes of material. The predicted probabilities and some of the volumes predicted for the modeled storms indicate a potential for substantial debris-flow impacts on structures, roads, bridges, and culverts located both within and

  10. The Burning Saints

    DEFF Research Database (Denmark)

    Xygalatas, Dimitris

    . Carrying the sacred icons of the saints, participants dance over hot coals as the saint moves them. The Burning Saints presents an analysis of these rituals and the psychology behind them. Based on long-term fieldwork, The Burning Saints traces the historical development and sociocultural context......, The Burning Saints presents a highly original analysis of how mental processes can shape social and religious behaviour....

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

    Science.gov (United States)

    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. The mechanism of lead catalysis of double-base rocket propellant combustion: Super-rate burning and the plateau/mesa phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Graham, W.H.; Neidert, J.B. (Thiokol Corp., Huntsville, AL (United States))

    1993-10-01

    Although double-base propellants contain a fairly complex mixture of ingredients, the most unstable compounds present are the nitrate esters, nitrocellulose and nitrate ester plasticizers, which represent the majority of most formulations; usually the ballistic additives, a lead compound and often carbon, represent from 1% to 5% of the total propellant. Energetic additives such as RDX and HMX are often present, but these nitramines are less responsive to lead catalysis which is characterized by a region of super-rate burning at lower pressures followed by a plateau region at higher pressure as the catalytic effectiveness appears to decrease and often a mesa region as the burn rate actually decreases with pressure. To explain both the super-rate burning and the plateau/mesa phenomena, one should logically examine the chemistry of decomposition of the nitrate esters to explain both lead catalysis and the apparent loss of catalysis; fortunately, examination of the reported chemistry of nitrate esters and several more recent investigations, which used sophisticated experimental techniques to examine double-base propellant combustion, provide support for a comprehensive mechanism to explain both.

  13. A miniature high repetition rate shock tube.

    Science.gov (United States)

    Tranter, R S; Lynch, P T

    2013-09-01

    A miniature high repetition rate shock tube with excellent reproducibility has been constructed to facilitate high temperature, high pressure, gas phase experiments at facilities such as synchrotron light sources where space is limited and many experiments need to be averaged to obtain adequate signal levels. The shock tube is designed to generate reaction conditions of T > 600 K, P shock waves with predictable characteristics are created, repeatably. Two synchrotron-based experiments using this apparatus are also briefly described here, demonstrating the potential of the shock tube for research at synchrotron light sources.

  14. Irradiation characteristics examination technology development of irradiated nuclear material and high burn-up fuels

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Kwon Pyo; Choo, Y. S.; Oh, Y. W. [and others

    2002-12-01

    The research and development for the first year of the project are performed through specialization of researchers, information from aborad and international cooperation, securement of advanced nuclear technology, development and installation of test equipment, application of external man-power, establishment of advanced test techniques, and certified test method. 1. Absolute efficiency measurement examination technology development of gamma scanning system 2. Sample preparation technology development of SEM and EPMA for micro-structural observation and chemical composition analysis 3. Irradiated high burn-up nuclear fuel transportation and test for PWR 4. Development of hot cell examination techniques and equipment 5. Acquirement of KOLAS system. In addition to the project, the following activities are carried out as follows; - PIE of Hanaro fuel(KH99H-001) - PIE of U-Mo advanced nuclear fuel irradiated at Hanaro - PIE of Hi-MET advanced nuclear fuel irradiated at Hanaro - PIE of DUPIC project - Hot cell examination of Hanaro irradiated capsule - Leaching test of PWR fuels - Surveillance test of PWR vessels - Mechanical test of CANDU pressure tubes.

  15. Electrical burns: Highlights from a 5-year retrospective analysis.

    Science.gov (United States)

    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

  16. High strain rate behaviour of polypropylene microfoams

    Science.gov (United States)

    Gómez-del Río, T.; Garrido, M. A.; Rodríguez, J.; Arencón, D.; Martínez, A. B.

    2012-08-01

    Microcellular materials such as polypropylene foams are often used in protective applications and passive safety for packaging (electronic components, aeronautical structures, food, etc.) or personal safety (helmets, knee-pads, etc.). In such applications the foams which are used are often designed to absorb the maximum energy and are generally subjected to severe loadings involving high strain rates. The manufacture process to obtain polymeric microcellular foams is based on the polymer saturation with a supercritical gas, at high temperature and pressure. This method presents several advantages over the conventional injection moulding techniques which make it industrially feasible. However, the effect of processing conditions such as blowing agent, concentration and microfoaming time and/or temperature on the microstructure of the resulting microcellular polymer (density, cell size and geometry) is not yet set up. The compressive mechanical behaviour of several microcellular polypropylene foams has been investigated over a wide range of strain rates (0.001 to 3000 s-1) in order to show the effects of the processing parameters and strain rate on the mechanical properties. High strain rate tests were performed using a Split Hopkinson Pressure Bar apparatus (SHPB). Polypropylene and polyethylene-ethylene block copolymer foams of various densities were considered.

  17. High strain rate behaviour of polypropylene microfoams

    Directory of Open Access Journals (Sweden)

    Martínez A.B.

    2012-08-01

    Full Text Available Microcellular materials such as polypropylene foams are often used in protective applications and passive safety for packaging (electronic components, aeronautical structures, food, etc. or personal safety (helmets, knee-pads, etc.. In such applications the foams which are used are often designed to absorb the maximum energy and are generally subjected to severe loadings involving high strain rates. The manufacture process to obtain polymeric microcellular foams is based on the polymer saturation with a supercritical gas, at high temperature and pressure. This method presents several advantages over the conventional injection moulding techniques which make it industrially feasible. However, the effect of processing conditions such as blowing agent, concentration and microfoaming time and/or temperature on the microstructure of the resulting microcellular polymer (density, cell size and geometry is not yet set up. The compressive mechanical behaviour of several microcellular polypropylene foams has been investigated over a wide range of strain rates (0.001 to 3000 s−1 in order to show the effects of the processing parameters and strain rate on the mechanical properties. High strain rate tests were performed using a Split Hopkinson Pressure Bar apparatus (SHPB. Polypropylene and polyethylene-ethylene block copolymer foams of various densities were considered.

  18. Influence of biomass burning from South Asia at a high-altitude mountain receptor site in China

    Directory of Open Access Journals (Sweden)

    J. Zheng

    2017-06-01

    Full Text Available Highly time-resolved in situ measurements of airborne particles were conducted at Mt. Yulong (3410 m above sea level on the southeastern edge of the Tibetan Plateau in China from 22 March to 14 April 2015. The detailed chemical composition was measured by a high-resolution time-of-flight aerosol mass spectrometer together with other online instruments. The average mass concentration of the submicron particles (PM1 was 5.7 ± 5.4 µg m−3 during the field campaign, ranging from 0.1 up to 33.3 µg m−3. Organic aerosol (OA was the dominant component in PM1, with a fraction of 68 %. Three OA factors, i.e., biomass burning organic aerosol (BBOA, biomass-burning-influenced oxygenated organic aerosol (OOA-BB and oxygenated organic aerosol (OOA, were resolved using positive matrix factorization analysis. The two oxygenated OA factors accounted for 87 % of the total OA mass. Three biomass burning events were identified by examining the enhancement of black carbon concentrations and the f60 (the ratio of the signal at m∕z 60 from the mass spectrum to the total signal of OA. Back trajectories of air masses and satellite fire map data were integrated to identify the biomass burning locations and pollutant transport. The western air masses from South Asia with active biomass burning activities transported large amounts of air pollutants, resulting in elevated organic concentrations up to 4-fold higher than those of the background conditions. This study at Mt. Yulong characterizes the tropospheric background aerosols of the Tibetan Plateau during pre-monsoon season and provides clear evidence that the southeastern edge of the Tibetan Plateau was affected by the transport of anthropogenic aerosols from South Asia.

  19. Influence of biomass burning from South Asia at a high-altitude mountain receptor site in China

    Science.gov (United States)

    Zheng, Jing; Hu, Min; Du, Zhuofei; Shang, Dongjie; Gong, Zhaoheng; Qin, Yanhong; Fang, Jingyao; Gu, Fangting; Li, Mengren; Peng, Jianfei; Li, Jie; Zhang, Yuqia; Huang, Xiaofeng; He, Lingyan; Wu, Yusheng; Guo, Song

    2017-06-01

    Highly time-resolved in situ measurements of airborne particles were conducted at Mt. Yulong (3410 m above sea level) on the southeastern edge of the Tibetan Plateau in China from 22 March to 14 April 2015. The detailed chemical composition was measured by a high-resolution time-of-flight aerosol mass spectrometer together with other online instruments. The average mass concentration of the submicron particles (PM1) was 5.7 ± 5.4 µg m-3 during the field campaign, ranging from 0.1 up to 33.3 µg m-3. Organic aerosol (OA) was the dominant component in PM1, with a fraction of 68 %. Three OA factors, i.e., biomass burning organic aerosol (BBOA), biomass-burning-influenced oxygenated organic aerosol (OOA-BB) and oxygenated organic aerosol (OOA), were resolved using positive matrix factorization analysis. The two oxygenated OA factors accounted for 87 % of the total OA mass. Three biomass burning events were identified by examining the enhancement of black carbon concentrations and the f60 (the ratio of the signal at m/z 60 from the mass spectrum to the total signal of OA). Back trajectories of air masses and satellite fire map data were integrated to identify the biomass burning locations and pollutant transport. The western air masses from South Asia with active biomass burning activities transported large amounts of air pollutants, resulting in elevated organic concentrations up to 4-fold higher than those of the background conditions. This study at Mt. Yulong characterizes the tropospheric background aerosols of the Tibetan Plateau during pre-monsoon season and provides clear evidence that the southeastern edge of the Tibetan Plateau was affected by the transport of anthropogenic aerosols from South Asia.

  20. Epidemiology of burns in Taiwan: a nationwide report including inpatients and outpatients.

    Science.gov (United States)

    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.

  1. Crude oil burning mechanisms

    DEFF Research Database (Denmark)

    van Gelderen, Laurens; Malmquist, Linus Mattias Valdemar; Jomaas, Grunde

    2015-01-01

    In order to improve predictions for the burning efficiency and the residue composition of in-situ burning of crude oil, the burning mechanism of crude oil was studied in relation to the composition of its hydrocarbon mixture, before, during and after the burning. The surface temperature, flame...... height, mass loss rate and residues of three hydrocarbon liquids (n-octane, dodecane and hexadecane), two crude oils (DUC and REBCO) and one hydrocarbon liquid mixture of the aforementioned hydrocarbon liquids were studied using the Crude Oil Flammability Apparatus. The experimental results were compared...... to the predictions of four conceptual models that describe the burning mechanism of multicomponent fuels. Based on the comparisons, hydrocarbon liquids were found to be best described by the Equilibrium Flash Vaporization model, showing a constant gas composition and gasification rate. The multicomponent fuels...

  2. Development of a method for xenon determination in the microstructure of high burn-up nuclear fuel[Dissertation 17527

    Energy Technology Data Exchange (ETDEWEB)

    Horvath, M. I

    2008-07-01

    , relevant Xe isotope concentrations in fission gas inclusions have not been reported yet. The aim of this work was focused on quantitative analysis of Xe isotope concentrations in inclusions of high burn-up samples to determine gas pressures within fuel pores. Therefore, various calibration strategies were studied in great detail. The investigation of Xe-implantation showed that the uncertainties in Xe ion implantation are too high to produce suitable Xe-implanted standard materials. The generation of Xe-bubbles in Plexiglass was also investigated and Xe inclusions of different bubble sizes were generated. However, the size determinations of the inclusions, the opening and possible gas losses through the Plexiglass were factors preventing accurate Xe quantification. The use of direct Xe gas injection was considered as a suitable strategy for establishing calibration curves. The Xe response was studied in dependence on gas concentration, gas volume and presence or absence of matrix in the ICP (Inductively Coupled Plasma). To investigate the ionization behavior of Xe in the ICP, the ablation behavior of ZrO{sub 2} and UO{sub 2} was determined in dependence on different wavelengths (266 nm, 193 nm), crater diameters, repetition rates and carrier gases (Ar, He). The mass ablated per laser pulse was very similar for the two matrices. The simultaneous introduction of matrix and gas into the ICP showed insignificant matrix effects. Even the absence of matrix effects was shown, filtering of the matrix before entering the plasma was evaluated to be crucial. Applying a filter leads to a complete gas/solid separation and opens access to the matrix interfering {sup 134}Xe and {sup 136}Xe isotopes. Thus, calibration gas addition in combination with an aerosol filter was the key strategy for quantification of Xe fission gas production in high burn-up fuel samples. Gas addition in volumes of 1 to 100 {mu}l and at a concentration of 20 and 200 {mu}g/g provided linear calibration curves

  3. Management of Hand Burns

    Directory of Open Access Journals (Sweden)

    Fatih Irmak

    2017-09-01

    Full Text Available Objective: The hand is one of the most frequently affected body parts by burn injuries with a rate of 80% among all burn wounds. Early and effective treatment ensures the best chance of survival as well as a good functional prognosis. The aim of this study was to determine the epidemiology, variation, relationship between etiology and hospital stay, clinical features, and management of hand burns. Material and Methods: This retrospective study was conducted the University of Health Sciences; Şişli Hamidiye Etfal Application and Research Center, Departmant of Plastic, Reconstructive and Aesthetic Surgery and the Intensive Burn Care Unit between April 2009 and April 2014. Burns were assessed based on etiology, anatomical location, percentage of total body surface area affected, and depth of injury. Treatment was categorized as conservative, elective operative, or urgent operative. Results: In the study period, 788 patients were admitted to our Burn Unit. Of these, 240 were females (30.5% and 548 were males (69.5%. The most common type of burn injury in this study was thermal injury (695 cases; 88.2%, followed by electrical injury (67 cases; 8.5%, and chemical, frictional or unknown injuries (26 cases; 3.3%. Majority (more than 85% of the patients had second-degree burns, and some had third-degree burns. Conclusions: Burns commonly affect the hands, and many functional problems may develop if appropriate basic treatments are neglected. The best treatment for burns is prevention. Appropriate indoor arrangement and simple but effective measures that can be taken at home can significantly reduce burn trauma exposure.

  4. High strain rate characterization of polymers

    Science.gov (United States)

    Siviour, Clive R.

    2017-01-01

    This paper reviews the literature on the response of polymers to high strain rate deformation. The main focus is on the experimental techniques used to characterize this response. The paper includes a small number of examples as well as references to experimental data over a wide range of rates, which illustrate the key features of rate dependence in these materials; however this is by no means an exhaustive list. The aim of the paper is to give the reader unfamiliar with the subject an overview of the techniques available with sufficient references from which further information can be obtained. In addition to the `well established' techniques of the Hopkinson bar, Taylor Impact and Transverse impact, a discussion of the use of time-temperature superposition in interpreting and experimentally replicating high rate response is given, as is a description of new techniques in which mechanical parameters are derived by directly measuring wave propagation in specimens; these are particularly appropriate for polymers with low wave speeds. The vast topic of constitutive modelling is deliberately excluded from this review.

  5. A prototype of a high rating MRPC

    Institute of Scientific and Technical Information of China (English)

    WANG Yi; WANG Jing-Bo; YAN Qiang; LI Yuan-Jing; CHENG Jian-Ping; YUE Qian; LI Jin

    2009-01-01

    Six-gap resistive plate chamber (MRPC) prototypes with semiconductive glass electrodes (bulk resistivity~1010.cm) were studied for suitability in time-of-flight (TOF) applications at high rates. These studies were performed using a continuous electron beam of 800 MeV at IHEP and an X-ray machine. Time resolutions of about 100 ps and efficiencies larger than 90% were obtained for flux densities up to 28 kHz/cm2.

  6. Reserve, flowing electrolyte, high rate lithium battery

    Science.gov (United States)

    Puskar, M.; Harris, P.

    Flowing electrolyte Li/SOCl2 tests in single cell and multicell bipolar fixtures have been conducted, and measurements are presented for electrolyte flow rates, inlet and outlet temperatures, fixture temperatures at several points, and the pressure drop across the fixture. Reserve lithium batteries with flowing thionyl-chloride electrolytes are found to be capable of very high energy densities with usable voltages and capacities at current densities as high as 500 mA/sq cm. At this current density, a battery stack 10 inches in diameter is shown to produce over 60 kW of power while maintaining a safe operating temperature.

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

    Science.gov (United States)

    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

  8. Abnormal strong burn-in degradation of highly efficient polymer solar cells caused by spinodal donor-acceptor demixing

    Science.gov (United States)

    Li, Ning; Perea, José Darío; Kassar, Thaer; Richter, Moses; Heumueller, Thomas; Matt, Gebhard J.; Hou, Yi; Güldal, Nusret S.; Chen, Haiwei; Chen, Shi; Langner, Stefan; Berlinghof, Marvin; Unruh, Tobias; Brabec, Christoph J.

    2017-02-01

    The performance of organic solar cells is determined by the delicate, meticulously optimized bulk-heterojunction microstructure, which consists of finely mixed and relatively separated donor/acceptor regions. Here we demonstrate an abnormal strong burn-in degradation in highly efficient polymer solar cells caused by spinodal demixing of the donor and acceptor phases, which dramatically reduces charge generation and can be attributed to the inherently low miscibility of both materials. Even though the microstructure can be kinetically tuned for achieving high-performance, the inherently low miscibility of donor and acceptor leads to spontaneous phase separation in the solid state, even at room temperature and in the dark. A theoretical calculation of the molecular parameters and construction of the spinodal phase diagrams highlight molecular incompatibilities between the donor and acceptor as a dominant mechanism for burn-in degradation, which is to date the major short-time loss reducing the performance and stability of organic solar cells.

  9. Abnormal strong burn-in degradation of highly efficient polymer solar cells caused by spinodal donor-acceptor demixing

    Science.gov (United States)

    Li, Ning; Perea, José Darío; Kassar, Thaer; Richter, Moses; Heumueller, Thomas; Matt, Gebhard J.; Hou, Yi; Güldal, Nusret S.; Chen, Haiwei; Chen, Shi; Langner, Stefan; Berlinghof, Marvin; Unruh, Tobias; Brabec, Christoph J.

    2017-01-01

    The performance of organic solar cells is determined by the delicate, meticulously optimized bulk-heterojunction microstructure, which consists of finely mixed and relatively separated donor/acceptor regions. Here we demonstrate an abnormal strong burn-in degradation in highly efficient polymer solar cells caused by spinodal demixing of the donor and acceptor phases, which dramatically reduces charge generation and can be attributed to the inherently low miscibility of both materials. Even though the microstructure can be kinetically tuned for achieving high-performance, the inherently low miscibility of donor and acceptor leads to spontaneous phase separation in the solid state, even at room temperature and in the dark. A theoretical calculation of the molecular parameters and construction of the spinodal phase diagrams highlight molecular incompatibilities between the donor and acceptor as a dominant mechanism for burn-in degradation, which is to date the major short-time loss reducing the performance and stability of organic solar cells. PMID:28224984

  10. Fission Gas Release in LWR Fuel Rods Exhibiting Very High Burn-Up

    DEFF Research Database (Denmark)

    Carlsen, H.

    1980-01-01

    Two UO2Zr BWR type test fuel rods were irradiated to a burn-up of about 38000 MWd/tUO2. After non-destructive characterization, the fission gas released to the internal free volume was extracted and analysed. The irradiation was simulated by means of the Danish fuel performance code WAFER-2, which...... uses an empirical gas release model combined with a strongly burn-up dependent correction term, developed by the US Nuclear Regulatory Commission. The paper presents the experimental results and the code calculations. It is concluded that the model predictions are in reasonable agreement (within 15...

  11. Reactive burn models and ignition & growth concept

    Directory of Open Access Journals (Sweden)

    Shaw M.S.

    2011-01-01

    Full Text Available Plastic-bonded explosives are heterogeneous materials. Experimentally, shock initiation is sensitive to small amounts of porosity, due to the formation of hot spots (small localized regions of high temperature. This leads to the Ignition & Growth concept, introduced by LeeTarver in 1980, as the basis for reactive burn models. A homo- genized burn rate needs to account for three meso-scale physical effects: (i the density of active hot spots or burn centers; (ii the growth of the burn fronts triggered by the burn centers; (iii a geometric factor that accounts for the overlap of deflagration wavelets from adjacent burn centers. These effects can be combined and the burn model defined by specifying the reaction progress variable λ = g(s as a function of a dimensionless reaction length s(t = rbc/ℓbc, rather than by specifying an explicit burn rate. The length scale ℓbc(Ps = [Nbc(Ps]−1/3 is the average distance between burn centers, where Nbc is the number density of burn centers activated by the lead shock. The reaction length rbc(t = ∫t0 D(P(t′dt′ is the distance the burn front propagates from a single burn center, where D(P is the deflagration speed as a function of the local pressure and t is the time since the shock arrival. A key implementation issue is how to determine the lead shock strength in conjunction with a shock capturing scheme. We have developed a robust algorithm for this purpose based on the Hugoniot jump condition for the energy. The algorithm utilizes the time dependence of density, pressure and energy within each cell. The method is independent of the numerical dissipation used for shock capturing. It is local and can be used in one or more space dimensions. The burn model has a small number of parameters which can be calibrated to fit velocity gauge data from shock initiation experiments.

  12. Importance of transboundary transport of biomass burning emissions to regional air quality in Southeast Asia during a high fire event

    Science.gov (United States)

    Aouizerats, B.; van der Werf, G. R.; Balasubramanian, R.; Betha, R.

    2015-01-01

    Smoke from biomass and peat burning has a notable impact on ambient air quality and climate in the Southeast Asia (SEA) region. We modeled a large fire-induced haze episode in 2006 stemming mostly from Indonesia using the Weather Research and Forecasting model coupled with chemistry (WRF-Chem). We focused on the evolution of the fire plume composition and its interaction with the urbanized area of the city state of Singapore, and on comparisons of modeled and measured aerosol and carbon monoxide (CO) concentrations. Two simulations were run with WRF-Chem using the complex volatility basis set (VBS) scheme to reproduce primary and secondary aerosol evolution and concentration. The first simulation referred to as WRF-FIRE included anthropogenic, biogenic and biomass burning emissions from the Global Fire Emissions Database (GFED3) while the second simulation referred to as WRF-NOFIRE was run without emissions from biomass burning. To test model performance, we used three independent data sets for comparison including airborne measurements of particulate matter (PM) with a diameter of 10 μm or less (PM10) in Singapore, CO measurements in Sumatra, and aerosol optical depth (AOD) column observations from four satellite-based sensors. We found reasonable agreement between the model runs and both ground-based measurements of CO and PM10. The comparison with AOD was less favorable and indicated the model underestimated AOD, although the degree of mismatch varied between different satellite data sets. During our study period, forest and peat fires in Sumatra were the main cause of enhanced aerosol concentrations from regional transport over Singapore. Analysis of the biomass burning plume showed high concentrations of primary organic aerosols (POA) with values up to 600 μg m-3 over the fire locations. The concentration of POA remained quite stable within the plume between the main burning region and Singapore while the secondary organic aerosol (SOA) concentration

  13. The Effect of Humidity on the Knock Behavior in a Medium BMEP Lean-Burn High-Speed Gas Engine

    NARCIS (Netherlands)

    van Essen, Vincent Martijn; Gersen, Sander; van Dijk, Gerco; Mundt, Torsten; Levinsky, Howard

    2016-01-01

    The effects of air humidity on the knock characteristics of fuels are investigated in a lean-burn, high-speed medium BMEP engine fueled with a CH4 + 4.7 mole% C3H8 gas mixture. Experiments are carried out with humidity ratios ranging from 4.3 to 11 g H2O/kg dry air. The measured pressure profiles at

  14. High strain rate deformation of layered nanocomposites

    Science.gov (United States)

    Lee, Jae-Hwang; Veysset, David; Singer, Jonathan P.; Retsch, Markus; Saini, Gagan; Pezeril, Thomas; Nelson, Keith A.; Thomas, Edwin L.

    2012-11-01

    Insight into the mechanical behaviour of nanomaterials under the extreme condition of very high deformation rates and to very large strains is needed to provide improved understanding for the development of new protective materials. Applications include protection against bullets for body armour, micrometeorites for satellites, and high-speed particle impact for jet engine turbine blades. Here we use a microscopic ballistic test to report the responses of periodic glassy-rubbery layered block-copolymer nanostructures to impact from hypervelocity micron-sized silica spheres. Entire deformation fields are experimentally visualized at an exceptionally high resolution (below 10 nm) and we discover how the microstructure dissipates the impact energy via layer kinking, layer compression, extreme chain conformational flattening, domain fragmentation and segmental mixing to form a liquid phase. Orientation-dependent experiments show that the dissipation can be enhanced by 30% by proper orientation of the layers.

  15. High frame-rate digital radiographic videography

    Energy Technology Data Exchange (ETDEWEB)

    King, N.S.P.; Cverna, F.H.; Albright, K.L.; Jaramillo, S.A.; Yates, G.J.; McDonald, T.E. [Los Alamos National Lab., NM (United States); Flynn, M.J.; Tashman, S. [Henry Ford Health System, Detroit, MI (United States)

    1994-09-01

    High speed x-ray imaging can be an important tool for observing internal processes in a wide range of applications. In this paper we describe preliminary implementation of a system having the eventual goal of observing the internal dynamics of bone and joint reactions during loading. Two Los Alamos National Laboratory (LANL) gated and image intensified camera systems were used to record images from an x-ray image convertor tube to demonstrate the potential of high frame-rate digital radiographic videography in the analysis of bone and joint dynamics of the human body. Preliminary experiments were done at LANL to test the systems. Initial high frame-rate imaging (from 500 to 1000 frames/s) of a swinging pendulum mounted to the face of an X-ray image convertor tube demonstrated high contrast response and baseline sensitivity. The systems were then evaluated at the Motion Analysis Laboratory of Henry Ford Health Systems Bone and Joint Center. Imaging of a 9 inch acrylic disk with embedded lead markers rotating at approximately 1000 RPM, demonstrated the system response to a high velocity/high contrast target. By gating the P-20 phosphor image from the X-ray image convertor with a second image intensifier (II) and using a 100-microsecond wide optical gate through the second II, enough prompt light decay from the x-ray image convertor phosphor had taken place to achieve reduction of most of the motion blurring. Measurement of the marker velocity was made by using video frames acquired at 500 frames/s. The data obtained from both experiments successfully demonstrated the feasibility of the technique. Several key areas for improvement are discussed along with salient test results and experiment details.

  16. Novel High Rate Lithium Intercalation Cathode Materials

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Application of amorphous V2O5/carbon/neodymium oxide (Nd2O3) composite is one of ways to surmount the lower electrical conductivity of V2O5. A new type of V2O5/carbon/Nd2O3 composite was prepared by mixing vanadium oxide hydrosol, acetone, carbon and Nd2O3 powder. High rate discharge/charge property of the composite electrode was tested electrochemically. This composite with Nd2O3 added shows the improvement of not only the discharge capacity but also cycle durability discharge capacity. The rate capability of the composite cathode also increases with the addition of Nd2O3.and cycle life are probably caused by the increase in porosity of open pores and short diffusion length of the active material on the lithium-ion insertion.

  17. Instrumented tube burns: theoretical and experimental observations

    Energy Technology Data Exchange (ETDEWEB)

    Yarrington, Cole Davis [Los Alamos National Laboratory; Obrey, Stephen J [Los Alamos National Laboratory; Foley, Timothy J [Los Alamos National Laboratory; Son, Steven F [Los Alamos National Laboratory

    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.

  18. On the Sensitivity of Massive Star Nucleosynthesis and Evolution to Solar Abundances and to Uncertainties in Helium-Burning Reaction Rates

    Science.gov (United States)

    Tur, Clarisse; Heger, Alexander; Austin, Sam M.

    2007-12-01

    We explore the dependence of presupernova evolution and supernova nucleosynthesis yields on the uncertainties in helium-burning reaction rates. Using the revised solar abundances of Lodders for the initial stellar composition, instead of those of Anders and Grevesse, changes the supernova yields and limits the constraints that those yields place on the 12C(α,γ)16O reaction rate. The production factors of medium-weight elements (A=16-40) were found to be in reasonable agreement with observed solar ratios within the current experimental uncertainties in the triple-α reaction rate. Simultaneous variations by the same amount in both reaction rates or in either of them separately, however, can induce significant changes in the central 12C abundance at core carbon ignition and in the mass of the supernova remnant. It therefore remains important to have experimental determinations of the helium-burning rates so that their ratio and absolute values are known with an accuracy of 10% or better.

  19. Pharmacokinetics of Imipenem/Cilastatin Burn Intensive Care Unit Patients Undergoing High-Dose Continuous Venovenous Hemofiltration.

    Science.gov (United States)

    Boucher, Bradley A; Hudson, Joanna Q; Hill, David M; Swanson, Joseph M; Wood, G Christopher; Laizure, S Casey; Arnold-Ross, Angela; Hu, Zhe-Yi; Hickerson, William L

    2016-12-01

    High-dose continuous venovenous hemofiltration (CVVH) is a continuous renal replacement therapy (CRRT) used frequently in patients with burns. However, antibiotic dosing is based on inference from studies assessing substantially different methods of CRRT. To address this knowledge gap for imipenem/cilastatin (I/C), we evaluated the systemic and extracorporeal clearances (CLs) of I/C in patients with burns undergoing high-dose CVVH. Prospective clinical pharmacokinetic study. Ten adult patients with burns receiving I/C for a documented infection and requiring high-dose CVVH were studied. Blood and effluent samples for analysis of I/C concentrations were collected for up to 6 hours after the I/C infusion for calculation of I/C total CL (CLTotal ), CL by CVVH (CLHF ), half-life during CVVH, volume of distribution at steady state (Vdss ), and the percentage of drug eliminated by CVVH. In this patient sample, the mean age was 50 ± 17 years, total body surface area burns was 23 ± 27%, and 80% were male. Nine patients were treated with high-dose CVVH for acute kidney injury and one patient for sepsis. The mean delivered CVVH dose was 52 ± 14 ml/kg/hour (range 32-74 ml/kg/hr). The imipenem CLHF was 3.27 ± 0.48 L/hour, which accounted for 23 ± 4% of the CLTotal (14.74 ± 4.75 L/hr). Cilastatin CLHF was 1.98 ± 0.56 L/hour, which accounted for 45 ± 19% of the CLTotal (5.16 + 2.44 L/hr). The imipenem and cilastatin half-lives were 1.77 ± 0.38 hours and 4.21 ± 2.31 hours, respectively. Imipenem and cilastatin Vdss were 35.1 ± 10.3 and 32.8 ± 13.8 L, respectively. Efficient removal of I/C by high-dose CVVH, a high overall clearance, and a high volume of distribution in burn intensive care unit patients undergoing this CRRT method warrant aggressive dosing to treat serious infections effectively depending on the infection site and/or pathogen. © 2016 Pharmacotherapy Publications, Inc.

  20. Recent view to the results of pulse tests in the IGR reactor with high burn-up fuel

    Energy Technology Data Exchange (ETDEWEB)

    Asmolov, V.; Yegorova, L. [Russian Research Centre, Moscow (Russian Federation)

    1996-03-01

    Testing of 43 fuel elements (13 fuel elements with high burn-up fuel, 10 fuel elements with preirradiated cladding and fresh fuel, and 20 non-irradiated fuel elements) was carried out in the IGR pulse reactor with a half width of the reactor power pulse of about 0.7 sec. Tests were conducted in capsules with no coolant flow and with standard initial conditions in the capsule of 20{degrees}C and 0.2 MPa. Two types of coolant were used: water and air. One purpose of the test program was to determine the thresholds and mechanisms of fuel rod failure under RIA conditions for VVER fuel rods over their entire exposure range, from zero to high burn-up. These failure thresholds are often used in safety analyses. The tests and analyses were designed to reveal the influence on fuel rod failure of (1) the mechanical properties of the cladding, (2) the pellet-to-cladding gap, (3) fuel burn-up, (4) fuel-to-coolant heat transfer, and other parameters. The resulting data base can also be used for validation of computer codes used for analyzing fuel rod behavior. Three types of test specimens were used in the tests, and diagrams of these specimens are shown in Fig. 1. {open_quotes}Type-C{close_quotes} specimens were re-fabricated from commercial fuel rods of the VVER-1000 type that had been subjected to many power cycles of operation in the Novovoronezh Nuclear Power Plant (NV NPP). {open_quotes}Type-D{close_quotes} specimens were fabricated from the same commercial fuel rods used above, but the high burn-up oxide fuel was removed from the cladding and was replaced with fresh oxide fuel pellets. {open_quotes}Type-D{close_quotes} specimens thus provided a means of separating the effects of the cladding and the oxide fuel pellets and were used to examine cladding effects only.

  1. Differences in resuscitation in morbidly obese burn patients may contribute to high mortality.

    Science.gov (United States)

    Rae, Lisa; Pham, Tam N; Carrougher, Gretchen; Honari, Shari; Gibran, Nicole S; Arnoldo, Brett D; Gamelli, Richard L; Tompkins, Ronald G; Herndon, David N

    2013-01-01

    The rising number of obese patients poses new challenges for burn care. These may include adjustments in calculations of burn size, resuscitation, ventilator wean, nutritional goals as well as challenges in mobilization. The authors have focused this observational study on resuscitation in the obese patient population in the first 48 hours after burn injury. Previous trauma studies suggest a prolonged time to reach end points of resuscitation in the obese compared to nonobese injured patients. The authors hypothesize that obese patients have worse outcomes after thermal injury and that differences in the response to resuscitation contribute to this disparity. The authors retrospectively analyzed data prospectively collected in a multicenter trial to compare resuscitation and outcomes in patients stratified by National Institutes of Health/World Health Organization body mass index (BMI) classification (BMI: normal weight, 18.5-24.9; overweight, 25-29.9, obese, 30-39.9; morbidly obese, ≥40). Because of the distribution of body habitus in the obese, total burn size was recalculated for all patients by using the method proposed by Neaman and compared with Lund-Browder estimates. The authors analyzed patients by BMI class for fluids administered and end points of resuscitation at 24 and 48 hours. Multivariate analysis was used to compare morbidity and mortality across BMI groups. The authors identified 296 adult patients with a mean TBSA of 41%. Patient and injury characteristics were similar across BMI categories. No significant differences were observed in burn size calculations by using Neaman vs Lund-Browder formulas. Although resuscitation volumes exceeded the predicted formula in all BMI categories, higher BMI was associated with less fluid administered per actual body weight (P = .001). Base deficit on admission was highest in the morbidly obese group at 24 and 48 hours. Furthermore, the morbidly obese patients did not correct their metabolic acidosis to the

  2. [Application of high-frequency ultrasound in dermabrasion of patients with deep partial-thickness burns].

    Science.gov (United States)

    Zang, C Y; Cao, Y Q; Xue, W J; Zhao, R; Zhang, M; Zhang, Y H; Feng, Z; Wang, Y B

    2017-02-20

    Objective: To investigate the application of high-frequency ultrasound in dermabrasion of patients with deep partial-thickness burns. Methods: Twenty-six patients with deep partial-thickness burns conforming to the study criteria were hospitalized in our unit from March 2015 to March 2016. Patients were all performed with dermabrasion. The structure of skin tissue and blood flow signals of uninjured side and wounds before dermabrasion, and those of wounds immediately post dermabrasion and on post dermabrasion day (PDD) 1, 3, 5, 7, 10, 14, and 21 were detected with high-frequency ultrasound, and the percentage of blood flow signals was calculated. According to the results of comparison between percentage of blood flow signals of wounds and that of normal skin before dermabrasion, patients were divided into no significant decrease group (NSD, n=19) and significant decrease group (SD, n=7). Wound healing time of patients in two groups was recorded. Data were processed with analysis of variance of repeated measurement, LSD test, t test and Chi-square test. The correlation between the percentage of blood flow signals of wounds before dermabrasion and wound healing time of 26 patients were analyzed by Spearman correlation analysis. Results: (1) Epidermis of normal skin of patients in two groups before dermabrasion showed continuous smooth linear hyperecho, which was stronger than that of dermis, and boundary of dermis and subcutaneous tissue showed stronger discontinuous linear echo than that of dermis, which gradually transited to subcutaneous tissue. In group NSD, epidermis of wound of patients before dermabrasion showed intermittent rough linear echo, which was weaker than that of normal skin epidermis, and there was no obvious abnormity of boundary between dermis and subcutaneous tissue. Immediately post dermabrasion and on PDD 1, no linear hyperecho of epidermis was observed, showing complete attrition of epidermis, and the echo of dermis and subcutaneous tissue had

  3. Experimental recombination rates for highly charged ions

    Energy Technology Data Exchange (ETDEWEB)

    Reinhold Schuch [Dept. of Atomic Physics, Stockholm Univ., Frescativ., Stockholm (Sweden)

    2000-01-01

    Recent studies of recombination between free electrons and highly charged ions using electron coolers of heavy-ion storage rings have produced accurate rate coefficients of interest for plasma modeling and diagnostics. Some surprises were discovered which can lead to revisions of recombination models. With bare ions one finds at low energy a strong and puzzling deviation from radiative recombination theory. Dielectronic recombination with C3+, N4+ show that jj coupling gives essential contributions to the cross section also for light ions. (author)

  4. MR imaging findings of high-voltage electrical burns in the upper extremities: correlation with angiographic findings

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Gyung Kyu; Kang, Ik Won; Hwang, Dae Hyun; Min, Seon Jung; Han, You Mi (Dept. of Radiology, Hallym Univ. College of Medicine, Hangang Sacred Heart Hospital, Seoul (Korea, Republic of)); Suh, Kyung Jin (Dept. of Radiology, Dongguk Univ. College of Medicine, Gyeongju Hospital, Gyeongju (Korea, Republic of)), email: kyungjin.suh@gmail.com; Choi, Min Ho (Dept. of Internal Medicine, Hallym Univ. College of Medicine, Hangang Sacred Heart Hospital, Seoul (Korea, Republic of))

    2011-02-15

    Background: A high-voltage electrical burn is often associated with deep muscle injuries. Hidden, undetected deep muscle injuries have a tendency for progressive tissue necrosis, and this can lead to major amputations or sepsis. MRI has excellent soft tissue contrast and it may aid in differentiating the areas of viable deep muscle from the areas of non-viable deep muscle. Purpose: To describe the MR imaging findings of a high-voltage electrical burn in the upper extremity with emphasis on the usefulness of the gadolinium-enhanced MRI and to compare the MR imaging findings with angiography. Material and Methods: We retrospectively reviewed the imaging studies of six patients with high-voltage electrical burns who underwent both MRI and angiography at the burn center of our hospital from January 2005 to December 2009. The imaging features were evaluated for the involved locations, the MR signal intensity of the affected muscles, the MR enhancement pattern, the involved arteries and the angiographic findings (classified as normal, sluggish flow, stenosis or occlusion) of the angiography of the upper extremity. We assessed the relationship between the MR imaging findings and the angiographic findings. Results: The signal intensities of affected muscles were isointense or of slightly high signal intensity as compared with the adjacent unaffected skeletal muscle on the T1-weighted MR images. Affected muscles showed heterogenous high signal intensity relative to the adjacent unaffected skeletal muscle on the T2- weighted images. The gadolinium-enhanced T1-weighted images showed diffuse inhomogeneous enhancement or peripheral rim enhancement of the affected muscles. The angiographic findings of the arterial injuries showed complete occlusion in three patients, severe stenosis in two patients and sluggish flow in one patient. Of these, the five patients with complete occlusion or severe stenosis on angiography showed non-perfused and non-viable areas of edematous muscle on

  5. Fibers innovative burning and reuse by Self-propagating High temperature Synthesis (SHS)

    Science.gov (United States)

    Caratto, Valentina; Belfortini, Claudio; Musi, Luigi; Gaggero, Laura; Ferretti, Maurizio

    2016-04-01

    The treatment of asbestos containing waste deriving from civil building and industrial applications is a social alert and an environmental problem. The project LIFE12 ENV/IT 000295 FIBERS "Fibers innovative burning and reuse by Self-propagating High temperature Synthesis (SHS)" has developed an innovative technique alternative to conventional high T processes. The University of Genoa has developed an apparatus and a technique for triggering the breakdown reaction of chrysotile by means of an alumino-thermic reaction in a process of combustion synthesis well known as Self-propagating High temperature Synthesis or SHS. This approach yielded interesting results and allowed the development of an efficient method for inerting natural asbestos fibers and man-made products carrying fibers at the scale of some grams [1]. The experiments were based on the couples Fe2O3/Mg by implementation of two prototype plants. The varying parameters were: 1) different Asbestos-Containing Waste (ACW) massive (Eternit, linoleum) and friable asbestos; 2) ACW abundance; 3) size of the pellet 4) under two triggering systems (induction by a W coil and oxyacetylene torch). The reactions were carried in two configurations: a) discontinuous, allowed us to obtain data for the development and fine-tuning of the reaction, b) continuous, was indispensable for the development and fine-tuning of the process parameters towards industrial scale up. After the combustive reaction all samples were characterized by SEM-EDS and XRPD analysis. All experiments demonstrated effective in destructing the fibrous habit of chrysotile, turning its composition to stubby olivine grains. We optimized the parameters to achieve complete conversion of the asbestos to mineral grains in all the cases. The efficiency of the SHS reaction in the discontinuous and continuous configurations was highlighted by the characterization of the post-combustion material under SEM-EDS and XRPD that verified the absence of fibers within

  6. Burn-related factors affecting anxiety, depression and self-esteem in burn patients: an exploratory study.

    Science.gov (United States)

    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.

  7. Nutrition of burned patients.

    Science.gov (United States)

    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.

  8. Recrystallization of High Carbon Steel during High Strain Rate

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The recrystallization of high carbon steel during high temperature and high speed rolling has been studied by analyzing the stress-strain curves and the austenite grain size.Isothermal multi-pass hot compression at high strain rate was carried out by Gleeble-2000. The austenite grain size was measured by IBAS image analysis system. The results show that static recrystallization occurred at interpass time under pre-finish rolling, and at the finish rolling stage, due to the brief interpass time, static recrystallization can not be found.

  9. Lattice parameter changes associated with the rim-structure formation in high burn-up UO 2 fuels by micro X-ray diffraction

    Science.gov (United States)

    Spino, J.; Papaioannou, D.

    2000-10-01

    Radial variations of the lattice parameter and peak width of two high burn-up UO 2-fuels (67 and 80 GWd/tM) were measured by a specially developed micro-X-ray diffraction technique, allowing spectra acquisition with 30 μm spatial resolution. The results showed a significant but constant peak broadening, and a lattice parameter that increased towards the pellet edge and decreased again within the rim-zone. This lattice contraction coincided with other property changes in the rim region, i.e., porosity increase, hardness decrease and Xe depletion. In terms of local burn-ups, the lattice contraction followed the rate of the matrix Xe depletion measured by EMPA, exceeding greatly the contraction rate due to dissolved fission products. The observed behaviour can be equally explained by a saturation of single interstitials with subsequent recombination with excess vacancies, as by the saturation and enlargement of dislocation loops. The concentration and sizes of defects involved and their possible relation to the rim structure formation are discussed.

  10. High counting rate resistive-plate chamber

    Science.gov (United States)

    Peskov, V.; Anderson, D. F.; Kwan, S.

    1993-05-01

    Parallel-plate avalanche chambers (PPAC) are widely used in physics experiments because they are fast (less than 1 ns) and have very simple construction: just two parallel metallic plates or mesh electrodes. Depending on the applied voltage they may work either in spark mode or avalanche mode. The advantage of the spark mode of operation is a large signal amplitude from the chamber, the disadvantage is that there is a large dead time (msec) for the entire chamber after an event. The main advantage of the avalanche mode is high rate capability 10(exp 5) counts/mm(sup 2). A resistive-plate chamber (RPC) is similar to the PPAC in construction except that one or both of the electrodes are made from high resistivity (greater than 10(exp 10) Omega(cm) materials. In practice RPC's are usually used in the spark mode. Resistive electrodes are charged by sparks, locally reducing the actual electric field in the gap. The size of the charged surface is about 10 mm(sup 2), leaving the rest of the detector unaffected. Therefore, the rate capability of such detectors in the spark mode is considerably higher than conventional spark counters. Among the different glasses tested the best results were obtained with electron type conductive glasses, which obey Ohm's law. Most of the work with such glasses was done with high pressure parallel-plate chambers (10 atm) for time-of-flight measurements. Resistive glasses have been expensive and produced only in small quantities. Now resistive glasses are commercially available, although they are still expensive in small scale production. From the positive experience of different groups working with the resistive glasses, it was decided to review the old idea to use this glass for the RPC. This work has investigated the possibility of using the RPC at 1 atm and in the avalanche mode. This has several advantages: simplicity of construction, high rate capability, low voltage operation, and the ability to work with non-flammable gases.

  11. Burns and military clothing.

    Science.gov (United States)

    McLean, A D

    2001-02-01

    high heat loads in the laboratory, combat clothing can ignite, but there is little evidence that clothing ignition is a common occurrence in military burn casualties. Thermoplastic materials have many benefits in civil and military clothing. There is little objective evidence that they exacerbate burns, or complicate burn management. Their use in military clothing must be based on objective evidence, not hearsay.

  12. High-energy, high-rate materials processing

    Science.gov (United States)

    Marcus, H. L.; Bourell, D. L.; Eliezer, Z.; Persad, C.; Weldon, W.

    1987-12-01

    The increasingly available range of pulsed-power, high energy kinetic storage devices, such as low-inductance pulse-forming networks, compulsators, and homopolar generators, is presently considered as a basis for industrial high energy/high rate (HEHR) processing to accomplish shock hardening, drilling, rapid surface alloying and melting, welding and cutting, transformation hardening, and cladding and surface melting in metallic materials. Time-temperature-transformation concepts furnish the basis for a fundamental understanding of the potential advantages of this direct pulsed power processing. Attention is given to the HEHR processing of a refractory molybdenum alloy, a nickel-base metallic glass, tungsten, titanium aluminides, and metal-matrix composites.

  13. Determination of PM10 and its ion composition emitted from biomass burning in the chamber for estimation of open burning emissions.

    Science.gov (United States)

    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(+).

  14. High-Frame-Rate Oil Film Interferometry

    CERN Document Server

    White, Jonathan C; Chen, John

    2010-01-01

    The fluid dynamics video to which this abstract relates contains visualization of the response of a laminar boundary layer to a sudden puff from a small hole. The boundary layer develops on a flat plate in a wind tunnel; the hole is located at a streamwise Reynolds number of 100,000. The visualization of the boundary layer response is accomplished using interferometry of a transparent, thin film of oil placed on the surface immediately downstream of the hole and with its leading edge perpendicular to the direction of flow. Through lubrication theory, it is understood that the rate of change of the spacing of the interference fringes is proportional to the skin friction at any instant. For reference, a small disk-shaped protrusion of the type often used to trip the boundary layer in wind model tunnel testing is also shown. Three cases with different puff strengths are included. Using a high-speed commercial camera, frame rates in excess of 1000/sec have been recorded; the video shown here was taken at 24 frame...

  15. High spin rate magnetic controller for nanosatellites

    Science.gov (United States)

    Slavinskis, A.; Kvell, U.; Kulu, E.; Sünter, I.; Kuuste, H.; Lätt, S.; Voormansik, K.; Noorma, M.

    2014-02-01

    This paper presents a study of a high rate closed-loop spin controller that uses only electromagnetic coils as actuators. The controller is able to perform spin rate control and simultaneously align the spin axis with the Earth's inertial reference frame. It is implemented, optimised and simulated for a 1-unit CubeSat ESTCube-1 to fulfil its mission requirements: spin the satellite up to 360 deg s-1 around the z-axis and align its spin axis with the Earth's polar axis with a pointing error of less than 3°. The attitude of the satellite is determined using a magnetic field vector, a Sun vector and angular velocity. It is estimated using an Unscented Kalman Filter and controlled using three electromagnetic coils. The algorithm is tested in a simulation environment that includes models of space environment and environmental disturbances, sensor and actuator emulation, attitude estimation, and a model to simulate the time delay caused by on-board calculations. In addition to the normal operation mode, analyses of reduced satellite functionality are performed: significant errors of attitude estimation due to non-operational Sun sensors; and limited actuator functionality due to two non-operational coils. A hardware-in-the-loop test is also performed to verify on-board software.

  16. High readmission rate after heart valve surgery

    DEFF Research Database (Denmark)

    Sibilitz, K L; Berg, S K; Thygesen, Lau Caspar;

    2015-01-01

    of anxiety and depression were present in 13.6% and 13.8%, respectively (Hospital Anxiety and Depression Scale score ≥ 8). Twelve months following discharge, 483 persons (56%) were readmitted. Readmission was associated with lower self-reported health (SF-36 PCS: 46.5 vs. 43.9, and MCS 52.2 vs. 50.7). Higher...... after surgery (3.2 (1.2-8.9)) predicted mortality. CONCLUSIONS: 6-12 months after heart valve surgery the readmission rate is high and the self-reported health status is low. Readmission is associated with low self-reported health. Therefore, targeted follow-up strategies post-surgery are needed....

  17. Consideration of wear rates at high velocity

    Science.gov (United States)

    Hale, Chad S.

    The development of the research presented here is one in which high velocity relative sliding motion between two bodies in contact has been considered. Overall, the wear environment is truly three-dimensional. The attempt to characterize three-dimensional wear was not economically feasible because it must be analyzed at the micro-mechanical level to get results. Thus, an engineering approximation was carried out. This approximation was based on a metallographic study identifying the need to include viscoplasticity constitutive material models, coefficient of friction, relationships between the normal load and velocity, and the need to understand wave propagation. A sled test run at the Holloman High Speed Test Track (HHSTT) was considered for the determination of high velocity wear rates. In order to adequately characterize high velocity wear, it was necessary to formulate a numerical model that contained all of the physical events present. The experimental results of a VascoMax 300 maraging steel slipper sliding on an AISI 1080 steel rail during a January 2008 sled test mission were analyzed. During this rocket sled test, the slipper traveled 5,816 meters in 8.14 seconds and reached a maximum velocity of 1,530 m/s. This type of environment was never considered previously in terms of wear evaluation. Each of the features of the metallography were obtained through micro-mechanical experimental techniques. The byproduct of this analysis is that it is now possible to formulate a model that contains viscoplasticity, asperity collisions, temperature and frictional features. Based on the observations of the metallographic analysis, these necessary features have been included in the numerical model, which makes use of a time-dynamic program which follows the movement of a slipper during its experimental test run. The resulting velocity and pressure functions of time have been implemented in the explicit finite element code, ABAQUS. Two-dimensional, plane strain models

  18. Pain in burn patients.

    Science.gov (United States)

    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.

  19. Calculation and Analysis of B/T (Burning and/or Transmutation Rate of Minor Actinides and Plutonium Performed by Fast B/T Reactor

    Directory of Open Access Journals (Sweden)

    Marsodi

    2006-01-01

    Full Text Available Calculation and analysis of B/T (Burning and/or Transmutation rate of MA (minor actinides and Pu (Plutonium has been performed in fast B/T reactor. The study was based on the assumption that the spectrum shift of neutron flux to higher side of neutron energy had a potential significance for designing the fast B/T reactor and a remarkable effect for increasing the B/T rate of MA and/or Pu. The spectrum shifts of neutron have been performed by change MOX to metallic fuel. Blending fraction of MA and or Pu in B/T fuel and the volume ratio of fuel to coolant in the reactor core were also considered. Here, the performance of fast B/T reactor was evaluated theoretically based on the calculation results of the neutronics and burn-up analysis. In this study, the B/T rate of MA and/or Pu increased by increasing the blending fraction of MA and or Pu and by changing the F/C ratio. According to the results, the total B/T rate, i.e. [B/T rate]MA + [B/T rate]Pu, could be kept nearly constant under the critical condition, if the sum of the MA and Pu inventory in the core is nearly constant. The effect of loading structure was examined for inner or outer loading of concentric geometry and for homogeneous loading. Homogeneous loading of B/T fuel was the good structure for obtaining the higher B/T rate, rather than inner or outer loading

  20. Upgrade Strategy for ALICE at High Rate

    CERN Document Server

    Musa, L

    2012-01-01

    The longterm goal of the ALICE experiment is to provide a precise characterization of the Quark-Gluon Plasma (QGP) state. Such a determination of its properties including initial temperature, degrees of freedom, speed of sound, and in general, transport coefficients would be a major achievement. This would go a long way towards a better understanding of QCD as a genuine multi-particle theory. To achieve this goal, high statistics measurements are required, which will give access also to the very rare physics channels needed to understand the dynamics of this condensed phase of QCD. The general upgrade strategy for the ALICE central barrel is conceived to deal with this challenge with expected Pb-Pb interaction rates of up to 50 kHz, that would provide an accumulated sample of the order of 10 nb^-1 in the period 2019-2023. In this document we sketch the modifications/replacements needed in all ALICE central barrel detectors and online systems (Trigger, DAQ and HLT) for high luminosity running. As the ALICE for...

  1. Organic functional groups in aerosol particles from burning and non-burning forest emissions at a high-elevation mountain site

    Directory of Open Access Journals (Sweden)

    S. Takahama

    2011-01-01

    Full Text Available Ambient particles collected on teflon filters at the Peak of Whistler Mountain, British Columbia (2182 m a.s.l. during spring and summer 2009 were measured by Fourier transform infrared (FTIR spectroscopy for organic functional groups (OFG. The project mean and standard deviation of organic aerosol mass concentrations (OM for all samples was 3.2±3.3 (μg m−3. The OM was dominated by regional forest sources, burning, and non-burning that occurred mostly during June–September. On average, organic hydroxyl, alkane, carboxylic acid, ketone, and amine, groups represented 31%±11%, 34%±9%, 23%±6%, 6%±7%, and 6%±3% of OM, respectively. Ketone groups were associated with the forest aerosols and represented up to 27% of the OM in these aerosols. Additional measurements of aerosol mass fragments, size, and number concentrations were used to separate fossil-fuel combustion and burning and non-burning forest sources of the measured organic aerosol. The OM concentrations observed at Whistler Peak during this campaign were higher than those measured during a shorter period in the spring of 2008 at a site in Whistler valley, over one km lower than the peak location. The 2009 campaign was largely influenced by the wildfire emissions that were absent during the 2008 campaign.

  2. Epidemiology of burns in Lithuania during 1991-2004.

    Science.gov (United States)

    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.

  3. The Complete Burning of Weapons Grade Plutonium and Highly Enriched Uranium with (Laser Inertial Fusion-Fission Energy) LIFE Engine

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, J C; Diaz de la Rubia, T; Moses, E

    2008-12-23

    The National Ignition Facility (NIF) project, a laser-based Inertial Confinement Fusion (ICF) experiment designed to achieve thermonuclear fusion ignition and burn in the laboratory, is under construction at the Lawrence Livermore National Laboratory (LLNL) and will be completed in April of 2009. Experiments designed to accomplish the NIF's goal will commence in late FY2010 utilizing laser energies of 1 to 1.3 MJ. Fusion yields of the order of 10 to 20 MJ are expected soon thereafter. Laser initiated fusion-fission (LIFE) engines have now been designed to produce nuclear power from natural or depleted uranium without isotopic enrichment, and from spent nuclear fuel from light water reactors without chemical separation into weapons-attractive actinide streams. A point-source of high-energy neutrons produced by laser-generated, thermonuclear fusion within a target is used to achieve ultra-deep burn-up of the fertile or fissile fuel in a sub-critical fission blanket. Fertile fuels including depleted uranium (DU), natural uranium (NatU), spent nuclear fuel (SNF), and thorium (Th) can be used. Fissile fuels such as low-enrichment uranium (LEU), excess weapons plutonium (WG-Pu), and excess highly-enriched uranium (HEU) may be used as well. Based upon preliminary analyses, it is believed that LIFE could help meet worldwide electricity needs in a safe and sustainable manner, while drastically shrinking the nation's and world's stockpile of spent nuclear fuel and excess weapons materials. LIFE takes advantage of the significant advances in laser-based inertial confinement fusion that are taking place at the NIF at LLNL where it is expected that thermonuclear ignition will be achieved in the 2010-2011 timeframe. Starting from as little as 300 to 500 MW of fusion power, a single LIFE engine will be able to generate 2000 to 3000 MWt in steady state for periods of years to decades, depending on the nuclear fuel and engine configuration. Because the fission

  4. Isotopic analyses and calculation by use of JENDL-3.2 for high burn-up UO{sub 2} and MOX spent fuels

    Energy Technology Data Exchange (ETDEWEB)

    Sasahara, Akihiro; Matsumura, Tetsuo [Central Research Inst. of Electric Power Industry, Komae, Tokyo (Japan). Komae Research Lab.; Nicolaou, G.; Betti, M.; Walker, C.T.

    1997-03-01

    The post irradiation examinations (PIE) were carried out for high burn-up UO{sub 2} spent fuel (3.8%U235, average burn-up:60GWd/t) and mixed oxide (MOX) spent fuel (5.07%Pu, average burn-up:45GWd/t). The PIE includes, (a) isotopic analysis, (b) electron probe microanalysis (EPMA) in pellet cross section and so on. The results of isotopic analyses and EPMA were compared with ORIGEN2/82 and VIM-BURN calculation results. In VIM-BURN calculation, the nuclear data of actinides were proceeded from new data file, JENDL-3.2. The sensitivities of power history and moderator density to nuclides composition were investigated by VIM-BURN calculation and consequently power history mainly effected on Am241 and Am242m and moderator density effected on fissile nuclides. From EPMA results of U and Pu distribution in pellet, VIM-BURN calculation showed reasonable distribution in pellet cross section. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  6. Social and Ecological Factors Influencing Attitudes Toward the Application of High-Intensity Prescribed Burns to Restore Fire Adapted Grassland Ecosystems

    Directory of Open Access Journals (Sweden)

    David Toledo

    2013-12-01

    Full Text Available Fire suppression in grassland systems that are adapted to episodic fire has contributed to the recruitment of woody species in grasslands worldwide. Even though the ecology of restoring these fire prone systems back to grassland states is becoming clearer, a major hurdle to the reintroduction of historic fires at a landscape scale is its social acceptability. Despite the growing body of literature on the social aspects of fire, an understanding of the human dimensions of applying high-intensity prescribed burns in grassland and savanna systems is lacking. We used structural equation modeling to examine how landowners' attitudes toward high-intensity prescribed burns are affected by previous experience with burning, perceptions of brush encroachment, land condition, proximity constraints, risk orientation, fire management knowledge and skill, access to fire management equipment, and subjective norms. Our results suggest that experience, risk taking orientation, and especially social norms, i.e., perceived support from others, when implementing prescribed burns play an important role in determining the attitudes of landowners toward the use of high-intensity prescribed burns. Concern over lack of skill, knowledge, and insufficient resources have a moderately negative effect on these attitudes. Our results highlight the importance of targeted engagement strategies to address risk perceptions, subjective norms, and landowner's concerns. With these concerns allayed, it is possible to increase the adoption of high-intensity prescribed burns that lead to landscape-scale grassland restoration and conservation.

  7. Saturday-morning television: do sponsors promote high-risk behavior for burn injury?

    Science.gov (United States)

    Palmieri, Tina L; Aoki, Traci; Combs, Elena; Curri, Terese; Garma, Sylvia; Kaulkin, Cammie; Lawless, Mary Beth; Nelson, Kate; Sanders, Johanna; Warden, Nancy; Greenhalgh, David G

    2004-01-01

    Television has become an important tool for learning and socialization in children. Although television violence has been associated with adverse effects, data on depiction of fire and burn injury are lacking. We sought to determine whether Saturday-morning television programming, viewed primarily by children, depicts fire and burn injury as safe or without consequence, thus potentially increasing the incidence of burn injury in children. This was a prospective observational study. Saturday-morning children's television programs were videotaped from 7 AM to 11 AM for eight different television networks during a 6-month period. Tapes were scored for scenes depicting fire or smoke by independent observers. Recorded items included show category, scene type, gender target, context of fire, and outcome after exposure to flame. Fire events were documented during programs and their associated commercials. A total of 108 hours of children's programs, 16 hours per network, were recorded. Scenes depicting fire or smoke were identified 1960 times, with 39% of events occurring during the program itself and 61% in commercials. Fire was depicted as either safe or without consequence in 64% of incidents. Action adventure stories accounted for 56% of flame depictions. Overall, one incident involving flame and fire was portrayed for each 3 minutes of television programming. Saturday-morning television programming frequently depicts fire as safe, empowering, or exciting. The incidence of flame use in programming varies between stations but is most prevalent in action/adventure stories. Television commercials, although brief, provide the majority of the misinformation regarding fire. Medical professional societies should alert the public to this potential hazard and recommend responsible portrayal of fire in children's television programming.

  8. The Fire INventory from NCAR (FINN): a high resolution global model to estimate the emissions from open burning

    Science.gov (United States)

    C. Wiedinmyer; S. K. Akagi; R. J. Yokelson; L. K. Emmons; J. A. Al-Saadi; J. J. Orlando; A. J. Soja

    2010-01-01

    The Fire INventory from NCAR version 1.0 (FINNv1) provides daily, 1 km resolution, global estimates of the trace gas and particle emissions from open burning of biomass, which includes wildfire, agricultural fires, and prescribed burning and does not include 5 biofuel use and trash burning. Emission factors used in the calculations have been updated with recent data,...

  9. High voltage high repetition rate pulse using Marx topology

    Science.gov (United States)

    Hakki, A.; Kashapov, N.

    2015-06-01

    The paper describes Marx topology using MOSFET transistors. Marx circuit with 10 stages has been done, to obtain pulses about 5.5KV amplitude, and the width of the pulses was about 30μsec with a high repetition rate (PPS > 100), Vdc = 535VDC is the input voltage for supplying the Marx circuit. Two Ferrite ring core transformers were used to control the MOSFET transistors of the Marx circuit (the first transformer to control the charging MOSFET transistors, the second transformer to control the discharging MOSFET transistors).

  10. HIgh Rate X-ray Fluorescence Detector

    Energy Technology Data Exchange (ETDEWEB)

    Grudberg, Peter Matthew [XIA LLC

    2013-04-30

    The purpose of this project was to develop a compact, modular multi-channel x-ray detector with integrated electronics. This detector, based upon emerging silicon drift detector (SDD) technology, will be capable of high data rate operation superior to the current state of the art offered by high purity germanium (HPGe) detectors, without the need for liquid nitrogen. In addition, by integrating the processing electronics inside the detector housing, the detector performance will be much less affected by the typically noisy electrical environment of a synchrotron hutch, and will also be much more compact than current systems, which can include a detector involving a large LN2 dewar and multiple racks of electronics. The combined detector/processor system is designed to match or exceed the performance and features of currently available detector systems, at a lower cost and with more ease of use due to the small size of the detector. In addition, the detector system is designed to be modular, so a small system might just have one detector module, while a larger system can have many you can start with one detector module, and add more as needs grow and budget allows. The modular nature also serves to simplify repair. In large part, we were successful in achieving our goals. We did develop a very high performance, large area multi-channel SDD detector, packaged with all associated electronics, which is easy to use and requires minimal external support (a simple power supply module and a closed-loop water cooling system). However, we did fall short of some of our stated goals. We had intended to base the detector on modular, large-area detectors from Ketek GmbH in Munich, Germany; however, these were not available in a suitable time frame for this project, so we worked instead with pnDetector GmbH (also located in Munich). They were able to provide a front-end detector module with six 100 m^2 SDD detectors (two monolithic arrays of three elements each) along with

  11. Cheetah: A high frame rate, high resolution SWIR image camera

    Science.gov (United States)

    Neys, Joel; Bentell, Jonas; O'Grady, Matt; Vermeiren, Jan; Colin, Thierry; Hooylaerts, Peter; Grietens, Bob

    2008-10-01

    A high resolution, high frame rate InGaAs based image sensor and associated camera has been developed. The sensor and the camera are capable of recording and delivering more than 1700 full 640x512pixel frames per second. The FPA utilizes a low lag CTIA current integrator in each pixel, enabling integration times shorter than one microsecond. On-chip logics allows for four different sub windows to be read out simultaneously at even higher rates. The spectral sensitivity of the FPA is situated in the SWIR range [0.9-1.7 μm] and can be further extended into the Visible and NIR range. The Cheetah camera has max 16 GB of on-board memory to store the acquired images and transfer the data over a Gigabit Ethernet connection to the PC. The camera is also equipped with a full CameralinkTM interface to directly stream the data to a frame grabber or dedicated image processing unit. The Cheetah camera is completely under software control.

  12. Burn epidemiology and cost of medication in paediatric burn patients.

    Science.gov (United States)

    Koç, Zeliha; Sağlam, Zeynep

    2012-09-01

    Burns are common injuries that cause problems to societies throughout the world. In order to reduce the cost of burn treatment in children, it is extremely important to determine the burn epidemiology and the cost of medicines used in burn treatment. The present study used a retrospective design, with data collected from medical records of 140 paediatric patients admitted to a burn centre between 1 January 2009 and 31 December 2009. Medical records were examined to determine burn epidemiology, medication administered, dosage, and duration of use. Descriptive statistical analysis was completed for all variables; chi-square was used to examine the relationship between certain variables. It was found that 62.7% of paediatric burns occur in the kitchen, with 70.7% involving boiling water; 55.7% of cases resulted in third-degree burns, 19.3% required grafting, and mean duration of hospital stay was 27.5 ± 1.2 days. Medication costs varied between $1.38 US dollars (USD) and $14,159.09, total drug cost was $46,148.03 and average cost per patient was $329.63. In this study, the medication cost for burn patients was found to be relatively high, with antibiotics comprising the vast majority of medication expenditure. Most paediatric burns are preventable, so it is vital to educate families about potential household hazards that can be addressed to reduce the risk of a burn. Programmes are also recommended to reduce costs and the inappropriate prescribing of medication.

  13. Study of Bacterial Infections among Burn Patients Hospitalized in Isfahan Burn Center

    Directory of Open Access Journals (Sweden)

    J. Faghri

    2007-10-01

    Full Text Available Introduction & Objective: Burn patients are at risk of acquiring infection because of destroy skin barrier, suppression of immunity, prolonged hospitalization, and invasive therapeutic and diagnostic procedure, risk of acquiring infection is high among burned patients. The aim of this study was to assess the incidence rate of bacterial etiology and infections among burn patients in the burn center of Isfahan. Materials & Methods: The study was conducted descriptive – cross sectional during a period of one year, (from august 2004 until September 2005. A total of 106 patients presenting with no signs and symptoms of infection within the first 48 hours of admission were included. CDC definition for nosocomial infections was applied. Each patient’s clinical examinations and records investigated daily. Swab culture, blood culture (during fever time, tissue culture from biopsy specimen of burn wound and urine culture obtained. The data were analyzed and interpreted using SPSS 10 Software, using Chi – square and Kappa Coefficient. P.value < 0.05 was significant. Results: One-hundred and six patients met the inclusion criteria, 91 (85/8% acquired at least one type of infection, including, urinary tract 28 (26/4%, blood stream 30 (28/3%, and burn wound 91(85/8%. Pseudomonas aeroginosa was the most common causative agent isolated from blood culture and swab culture, 27/42% and 54/4% respectively. Also, E.coli was the major casautive agent of urinary tract infections (6.4% isolated from urine culture of these burn patients.Conclusion: The results indicated that, biopsy from burn wounds and study of histopathologic specimen day by other day depends on blood and urine culture conditions overall can be effective for early detection of burn wounds infections.

  14. MRI findings of the brain in high-voltage electrical burn patient: case report

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Cheung Sook; Hong, Sung Hwan; Lee, Myung Joon; Cho, Seong Whi; Lee, Eil Seong; Kang, Ik Won [Hallym University College of Medicine, Seoul (Korea, Republic of)

    2003-05-01

    We report the delayed sequelae arising in a case of electrical injury, reviewing the literature on the subject and focusing on the MRI findings of the brain. A 23-year-old male suffered burns to the left parietal scalp, both feet, and the anterior chest wall. Neurological symptoms and MRI abnormalities appeared 14 days after the insult and continued for about three months. T1-weight MR images demonstrated homogeneous hypointensity, while T2-weighted images depicted hyperintense finger-like projections. Contrast-enhanced T1-weighted images demonstrated strong band-like enhancement, indicating meningeal hyperemia. Follow-up MR imaging showed that the lesion had disappeared, indicating that the cerebral edema and meaningeal hyperemia were reversible.

  15. Combustion Mechanisms of Very High Burn Rate (VHBR) Propellant. Phase II.

    Science.gov (United States)

    1995-09-01

    data which resulted from these tests consisted of video image(s) recorded from the screen of the image intensifier, in the form of either a cinematic ...Therefore, for these samples to be more easily ignited and to actually bum slightly faster, some type of kinetic effect triggered by the presence of the...Now, it should be noted that these calculations reflect equilibrium conditions and do not represent any kinetic events which may be present in the

  16. Characterization of high-resolution aerosol mass spectra of primary organic aerosol emissions from Chinese cooking and biomass burning

    Directory of Open Access Journals (Sweden)

    L.-Y. He

    2010-09-01

    Full Text Available Aerosol Mass Spectrometer (AMS has proved to be a powerful tool to measure submicron particulate composition with high time resolution. Factor analysis of mass spectra (MS collected worldwide by AMS demonstrates that submicron organic aerosol (OA is usually composed of several major components, such as oxygenated (OOA, hydrocarbon-like (HOA, biomass burning (BBOA, and other primary OA. In order to help interpretation of component MS from factor analysis of ambient OA datasets, AMS measurement of different primary sources is required for comparison. Such work, however, has been very scarce in the literature, especially for high resolution MS (HR-MS measurement, which performs improved characterization by separating the ions of different elemental compositions at each m/z in comparison with unit mass resolution MS (UMR-MS measurement. In this study, primary emissions from four types of Chinese cooking (CC and six types of biomass burning (BB were simulated systemically and measured using an Aerodyne High-Resolution Time-of-Flight AMS (HR-ToF-AMS. The MS of the CC emissions show high similarity with m/z 41 and m/z 55 being the highest signals; the MS of the BB emissions also show high similarity with m/z 29 and m/z 43 being the highest signals. The MS difference between the CC and BB emissions is much bigger than that between different CC (or BB types, especially for the HR-MS. The O/C ratio of OA ranges from 0.08 to 0.13 for the CC emissions while from 0.18 to 0.26 for the BB emissions. The ions of m/z 43, m/z 44, m/z 57, and m/z 60, usually used as tracer ions in AMS measurement, were examined for their HR-MS characteristics in the CC and BB emissions. Moreover, the MS of the CC and BB emissions are also used to compare with component MS from factor analysis of ambient OA datasets observed in China, as well as with other AMS measurements of primary sources in the literature. The MS

  17. Burn Injury Arise From Flying Balloon Toys

    OpenAIRE

    Yalcin Kulahci; Fatih Zor; Mehmet Bozkurt; Serdar Ozturk; Mustafa Sengezer

    2007-01-01

    Many of peoples are faced minor or major burn injuries in their life. Even the most widespread burn cause is flame injuries, too different burn cause pointed out in literature like Acetylen burns. The cases which imply in literature, mostly causes from explosion of high pressure acetylene tube, metal oxygene patch flame or carbide lamp using from cave explorers. An interesting acetylene burn cause in Turkey was publised by the authors. This cases was to come into being from flying toy balloon...

  18. Management of burn wounds.

    Science.gov (United States)

    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.

  19. Development of newly designed wood burning systems with low emissions and high efficiency; Tehokkaan ja vaehaepaeaestoeisen puulaemmitysjaerjestelmaen kehittaeminen

    Energy Technology Data Exchange (ETDEWEB)

    Hyytiaeinen, H. [Tulisydaen Oy, Vantaa (Finland)

    1997-12-01

    The investigations in the project will focus on the combustion behaviour of wood burning systems of untreated wood fuels with batch-wise and quasi-continuous mechanical feeding. The objectives will be to minimise the pollutant release of these combustion systems during the different operational phases by a consequent optimisation of the fuel burning technique and to reduce the CO release by increasing the efficiency of the combustion. To reduce the pollutant release during the operation phases and to increase the efficiency, products of incomplete combustion i.e. carbon monoxide, toxic organic compounds like benzene, polycyclic aromatic hydrocarbons and soot have to be minimised in a further extent. For that the following goals will be attained: improvement of the mixing process of combustion gases in the reaction zones, averaging the residence time spectrum in the burnout zone reduction, of emissions during initial and burnout phase in firings with batch-wise feeding reduction of emissions under partial-load conditions in firings with quasi-continuous feeding, higher combustion stability even in case of changing fuel qualities, defining guidelines for the design of stoves and boilers with low emissions and high efficiency. By the foreseen reduction of the pollutant release and improved efficiency the environmental acceptance of wood combustion firings can be increased and for instance local restrictions can be removed. The project is funded in part by The European Commission in the framework of The Non Nuclear Energy Programme. (orig.)

  20. Measurements of VOC/SVOC emission factors from burning incenses in an environmental test chamber: influence of temperature, relative humidity, and air exchange rate.

    Science.gov (United States)

    Manoukian, A; Buiron, D; Temime-Roussel, B; Wortham, H; Quivet, E

    2016-04-01

    This study investigates the influence of three environmental indoor parameters (i.e., temperature, relative humidity, and air exchange rate) on the emission of 13 volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs) during incense burning. Experiments have been carried out using an environmental test chamber. Statistical results from a classical two-level full factorial design highlight the predominant effect of ventilation on emission factors. The higher the ventilation, the higher the emission factor. Moreover, thanks to these results, an estimation of the concentration range for the compounds under study can be calculated and allows a quick look of indoor pollution induced by incense combustion. Carcinogenic substances (i.e., benzene, benzo(a)pyrene, and formaldehyde) produced from the incense combustion would be predicted in typical living indoors conditions to reach instantaneous concentration levels close to or higher than air quality exposure threshold values.

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

    Energy Technology Data Exchange (ETDEWEB)

    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 the trace gas emission factors from 7 prescribed fires in South Carolina, U.S. using two Fourier transform infrared spectrometer (FTIR) systems and whole air sampling (WAS) into canisters followed by gas-chromatographic analyses. The fires were intended to emulate high-intensity burns as they were lit during the dry season and in most cases represented stands that had not been treated with prescribed burns in 10+ years, if at all. A total of 97 trace gas species are reported here from both airborne and ground-based platforms making this one of the most detailed field studies of fire emissions to date. The measurements included the first data for a suite of monoterpene compounds emitted via distillation of plant tissues during real fires. The known chemistry of the monoterpenes and their measured abundance of ~0.40% of CO (molar basis), ~3.9% of NMOC (molar basis), and ~21% of organic aerosol (mass basis), suggests that they impacted post-emission formation of ozone, aerosol, and small organic trace gases such as methanol and formaldehyde in the sampled plumes. The variability in the terpene emissions in South Carolina (SC) fire plumes was high and, in general, the speciation of the emitted gas-phase non-methane organic compounds was surprisingly different from that observed in a similar study in nominally similar pine forests in North Carolina ~20 months earlier. It is likely that the slightly different ecosystems, time of year and the precursor variability all contributed to the variability in plume chemistry observed in this study and in the literature. The ΔHCN/ΔCO emission ratio, however, is fairly consistent at 0.9 ± 0.06 % for airborne fire measurements in coniferous-dominated ecosystems further confirming the value of HCN as a good biomass burning indicator/tracer. The SC results also support an earlier finding that C3-C4 alkynes may be of use as biomass burning indicators on the time-scale of

  2. The Myth of a High Savings Rate

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In an attempt to entice consumers to save less and spend more, China has focused on perfecting its social security system, reforming taxation and dividend-sharing proportion between the government and state-owned enterprises. Liu Yuhui, Director of the China Economy Appraisal and Rating Center at the Institute of Finance and Banking, the Chinese Academy of Social Sciences, offered his insights in an Economic Observer article. Edited excerpts follow

  3. Is aridity a high-order control on the hydro-geomorphic response of burned landscapes?

    Science.gov (United States)

    Sheridan, Gary; Van der Sant, Rene; Nyman, Petter; Lane, Patrick

    2015-04-01

    Fire results in hydro-geomorphic changes that are spatially variable and difficult to predict. In this study we compile 294 infiltration measurements, ten other soil, catchment runoff and erosion datasets, and a year of new data from 15 natural runoff plots across an aridity gradient from the eastern Victorian uplands in SE Australia. The results show that aridity (a function of the long term mean precipitation and net radiation) is associated with low post-fire infiltration capacities, increasing the chance of surface runoff, and strongly increasing the chance of debris flows. Runoff plots from the wettest site (aridity = 1.1) had an average runoff ratio of 0.3% compared with 33.6% for the most arid sites (aridity = 2.4). Post-fire debris flows were only observed in the more arid locations within the Victorian uplands, and resulted in erosion rates more than two orders of magnitude greater than non-debris flow processes. We therefore argue that in south eastern Australia aridity is a high-order control on the magnitude of post-wildfire hydro-geomorphic processes. The results from this Australian study may also help to provide insight into the landscape controls on post fire debris flows elsewhere. Aridity is a landscape-scale parameter that is mappable at a high resolution and therefore is a useful predictor of the spatial variability of the magnitude of post-fire hydro-geomorphic responses.

  4. Historic records of organic aerosols from a high Alpine glacier: implications of biomass burning, anthropogenic emissions, and dust transport

    Directory of Open Access Journals (Sweden)

    C. Müller-Tautges

    2015-05-01

    Full Text Available Historic records of α-dicarbonyls (glyoxal, methylglyoxal, carboxylic acids (C6–C12 dicarboxylic acids, pinic acid, p-hydroxybenzoic acid, phthalic acid, 4-methylphthalic acid, and major ions (oxalate, formate, calcium were determined with annual resolution in an ice core from Grenzgletscher in the southern Swiss Alps, covering the time period from 1942 to 1993. Measurements were conducted using ultra-high performance liquid chromatography (UHPLC coupled to electrospray ionization high resolution mass spectrometry (ESI-HRMS. For the first time, long-term records of the carboxylic acids and dicarbonyls as well as their source apportionment are reported for Western Europe. Source assignment of the organic species present in the ice core was performed using principal component analysis. Our results suggest biomass burning, anthropogenic emissions, and transport of mineral dust to be the main parameters influencing the concentration of organic compounds. Ice core records of several highly correlated compounds (e.g. p-hydroxybenzoic acid, pinic acid, C7 and C8 dicarboxylic acids can be related to the forest fire history in southern Switzerland. P-hydroxybenzoic acid was found to be the best organic fire tracer in the study area, revealing the highest correlation with the burned area from fires. Historical records of methylglyoxal, phthalic acid, and dicarboxylic acids C6, C10, and C12 are comparable with that of anthropogenic emissions of volatile organic compounds (VOCs. The small organic acids oxalic acid and formic acid are both highly correlated with calcium, suggesting their records to be affected by changing mineral dust transport to the drilling site.

  5. Historic records of organic compounds from a high Alpine glacier: influences of biomass burning, anthropogenic emissions, and dust transport

    Science.gov (United States)

    Müller-Tautges, C.; Eichler, A.; Schwikowski, M.; Pezzatti, G. B.; Conedera, M.; Hoffmann, T.

    2016-01-01

    Historic records of α-dicarbonyls (glyoxal, methylglyoxal), carboxylic acids (C6-C12 dicarboxylic acids, pinic acid, p-hydroxybenzoic acid, phthalic acid, 4-methylphthalic acid), and ions (oxalate, formate, calcium) were determined with annual resolution in an ice core from Grenzgletscher in the southern Swiss Alps, covering the time period from 1942 to 1993. Chemical analysis of the organic compounds was conducted using ultra-high-performance liquid chromatography (UHPLC) coupled to electrospray ionization high-resolution mass spectrometry (ESI-HRMS) for dicarbonyls and long-chain carboxylic acids and ion chromatography for short-chain carboxylates. Long-term records of the carboxylic acids and dicarbonyls, as well as their source apportionment, are reported for western Europe. This is the first study comprising long-term trends of dicarbonyls and long-chain dicarboxylic acids (C6-C12) in Alpine precipitation. Source assignment of the organic species present in the ice core was performed using principal component analysis. Our results suggest biomass burning, anthropogenic emissions, and transport of mineral dust to be the main parameters influencing the concentration of organic compounds. Ice core records of several highly correlated compounds (e.g., p-hydroxybenzoic acid, pinic acid, pimelic, and suberic acids) can be related to the forest fire history in southern Switzerland. P-hydroxybenzoic acid was found to be the best organic fire tracer in the study area, revealing the highest correlation with the burned area from fires. Historical records of methylglyoxal, phthalic acid, and dicarboxylic acids adipic acid, sebacic acid, and dodecanedioic acid are comparable with that of anthropogenic emissions of volatile organic compounds (VOCs). The small organic acids, oxalic acid and formic acid, are both highly correlated with calcium, suggesting their records to be affected by changing mineral dust transport to the drilling site.

  6. LIQUID ARGON CALORIMETER PERFORMANCE AT HIGH RATES

    CERN Document Server

    Kukhtin, V; The ATLAS collaboration

    2011-01-01

    The performance of the ATLAS liquid argon endcap and forward calorimeters has been projected at the planned high luminosity LHC option HL-LHC by exposing small calorimeter modules of the electromagnetic, hadronic, and forward calorimeters to high intensity proton beams at IHEP/Protvino accelerator. The results of HV current and of pulse shape analysis, and also the dependence of signal amplitude on beam intensity are presented.

  7. A primer on burn resuscitation

    Directory of Open Access Journals (Sweden)

    Bacomo Ferdinand

    2011-01-01

    Full Text Available Since the early 1900s, the scope of burn resuscitation has evolved dramatically. Due to various advances in pre-hospital care and training, under-resuscitation of patients with severe burns is now relatively uncommon. Over-resuscitation, otherwise known as "fluid creep", has emerged as one of the most important problems during the initial phases of burn care over the past decade. To avoid the complications of over-resuscitation, careful hourly titration of fluid rates based on compilation of various clinical end points by a bedside provider is vital. The aim of this review is to provide a practical approach to the resuscitation of severely burned patients.

  8. High Reproduction Rate versus Sexual Fidelity

    OpenAIRE

    Sousa, A. O.; de Oliveira, S. Moss

    2000-01-01

    We introduce fidelity into the bit-string Penna model for biological ageing and study the advantage of this fidelity when it produces a higher survival probability of the offspring due to paternal care. We attribute a lower reproduction rate to the faithful males but a higher death probability to the offspring of non-faithful males that abandon the pups to mate other females. The fidelity is considered as a genetic trait which is transmitted to the male offspring (with or without error). We s...

  9. Smoking Rates Still High in Some Racial Groups, CDC Reports

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_160256.html Smoking Rates Still High in Some Racial Groups, CDC ... lot of progress in getting Americans to stop smoking, some groups still have high smoking rates, a ...

  10. Using Coupled Mesoscale Experiments and Simulations to Investigate High Burn-Up Oxide Fuel Thermal Conductivity

    Science.gov (United States)

    Teague, Melissa C.; Fromm, Bradley S.; Tonks, Michael R.; Field, David P.

    2014-12-01

    Nuclear energy is a mature technology with a small carbon footprint. However, work is needed to make current reactor technology more accident tolerant and to allow reactor fuel to be burned in a reactor for longer periods of time. Optimizing the reactor fuel performance is essentially a materials science problem. The current understanding of fuel microstructure have been limited by the difficulty in studying the structure and chemistry of irradiated fuel samples at the mesoscale. Here, we take advantage of recent advances in experimental capabilities to characterize the microstructure in 3D of irradiated mixed oxide (MOX) fuel taken from two radial positions in the fuel pellet. We also reconstruct these microstructures using Idaho National Laboratory's MARMOT code and calculate the impact of microstructure heterogeneities on the effective thermal conductivity using mesoscale heat conduction simulations. The thermal conductivities of both samples are higher than the bulk MOX thermal conductivity because of the formation of metallic precipitates and because we do not currently consider phonon scattering due to defects smaller than the experimental resolution. We also used the results to investigate the accuracy of simple thermal conductivity approximations and equations to convert 2D thermal conductivities to 3D. It was found that these approximations struggle to predict the complex thermal transport interactions between metal precipitates and voids.

  11. High frame rate imaging based photometry

    DEFF Research Database (Denmark)

    Harpsøe, Kennet Bomann West; Jørgensen, U. G.; Andersen, M. I.;

    2012-01-01

    in conventional CCDs, and new methods for handling these must be developed. We aim to investigate how the normal photometric reduction steps from conventional CCDs should be adjusted to be applicable to EMCCD data. One complication is that a bias frame cannot be obtained conventionally, as the output from...... an EMCCD is not normally distributed. Also, the readout process generates spurious charges in any CCD, but in EMCCD data, these charges are visible as opposed to the conventional CCD. Furthermore we aim to eliminate the photon waste associated with lucky imaging by combining this method with shift......-and-add. A simple probabilistic model for the dark output of an EMCCD is developed. Fitting this model with the expectation-maximization algorithm allows us to estimate the bias, readout noise, amplification, and spurious charge rate per pixel and thus correct for these phenomena. To investigate the stability...

  12. High Count Rate Electron Probe Microanalysis

    Science.gov (United States)

    Geller, Joseph D.; Herrington, Charles

    2002-01-01

    Reducing the measurement uncertainty of quantitative analyses made using electron probe microanalyzers (EPMA) requires a careful study of the individual uncertainties from each definable step of the measurement. Those steps include measuring the incident electron beam current and voltage, knowing the angle between the electron beam and the sample (takeoff angle), collecting the emitted x rays from the sample, comparing the emitted x-ray flux to known standards (to determine the k-ratio) and transformation of the k-ratio to concentration using algorithms which includes, as a minimum, the atomic number, absorption, and fluorescence corrections. This paper discusses the collection and counting of the emitted x rays, which are diffracted into the gas flow or sealed proportional x-ray detectors. The representation of the uncertainty in the number of collected x rays collected reduces as the number of counts increase. The uncertainty of the collected signal is fully described by Poisson statistics. Increasing the number of x rays collected involves either counting longer or at a higher counting rate. Counting longer means the analysis time increases and may become excessive to get to the desired uncertainty. Instrument drift also becomes an issue. Counting at higher rates has its limitations, which are a function of the detector physics and the detecting electronics. Since the beginning of EPMA analysis, analog electronics have been used to amplify and discriminate the x-ray induced ionizations within the proportional counter. This paper will discuss the use of digital electronics for this purpose. These electronics are similar to that used for energy dispersive analysis of x rays with either Si(Li) or Ge(Li) detectors except that the shaping time constants are much smaller. PMID:27446749

  13. High pressure, high strain rate material strength studies

    Science.gov (United States)

    Remington, B. A.; Arsenlis, A.; Barton, N.; Belof, J.; Cavallo, R.; Maddox, B.; Park, H.-S.; Prisbrey, S.; Rudd, R.; Comley, A.; Meyers, M.; Wark, J.

    2011-10-01

    Constitutive models for material strength are currently being tested at high pressures by comparing 2D simulations with experiments measuring the Rayleigh-Taylor (RT) instability evolution in solid-state samples of vanadium (V), tantalum (Ta), and iron (Fe). The multiscale strength models being tested combine molecular dynamics, dislocation dynamics, and continuum simulations. Our analysis for the V experiments suggests that the material deformation at these conditions falls into the phonon drag regime, whereas for Ta, the deformation resides mainly in the thermal activation regime. Recent Fe-RT experiments suggest perturbation growth about the alpha-epsilon (bcc-hcp) phase transition threshold has been observed. Using the LLNL multiscale models, we decompose the strength as a function of strain rate into its dominant components of thermal activation, phonon drag, and work hardening. We have also developed a dynamic diffraction diagnostic technique to measure strength directly from shock compressed single crystal samples. Finally, recovery experiments allow a comparison of residual dislocation density with predictions from the multiscale model. This work performed under the auspices of the U.S. DoE by LLNL Security, LLC under Contract DE-AC52-07NA27344.

  14. Retrospective analysis of burn injuries caused by hot milk in 159 pediatric patients: 14 years of experience in a burn unit.

    Science.gov (United States)

    Yontar, Yalcin; Esmaoglu, Aliye; Coruh, Atilla

    2014-07-01

    The aim of this study was to investigate the hot milk burns among the pediatric patients and to compare our experiences with similar studies in the literature. A 14-year retrospective study was conducted on 159 pediatric patients with hot milk burn who hospitalized at the Burn Unit of Erciyes University Medical Faculty. There were 81 male and 78 female patients with a male to female ratio of 1.03:1. The mean age of the patients was 2.7±1.6 years. The initial injury was immersion in 59.7% of the patients and spillage in 40.3%. The mean burned body surface area of the patients was 18.6±10.8%. Twenty-two percent of the patients had moderate, and 78% had major burn trauma. Forty-nine percent of the patients received burn wound debridement and reconstruction with auto-skin grafts. Our burn unit's mortality rate was 1.5% among 542 pediatric patients with hot water, and 5.6% among 159 pediatric patients with hot milk burn during the same period, respectively. Hot milk burns should be considered as separately from other hot liquid burns which do not contain fat such as water, tea, and coffee. Physical and chemical properties of milk because of its high content of fat give rise to more tissue destruction, increased morbidity and mortality.

  15. High-Rate Capable Floating Strip Micromegas

    CERN Document Server

    Bortfeldt, Jonathan; Biebel, Otmar; Danger, Helge; Flierl, Bernhard; Hertenberger, Ralf; Lösel, Philipp; Moll, Samuel; Parodi, Katia; Rinaldi, Ilaria; Ruschke, Alexander; Zibell, André

    2015-01-01

    We report on the optimization of discharge insensitive floating strip Micromegas (MICRO-MEsh GASeous) detectors, fit for use in high-energy muon spectrometers. The suitability of these detectors for particle tracking is shown in high-background environments and at very high particle fluxes up to 60MHz/cm$^2$. Measurement and simulation of the microscopic discharge behavior have demonstrated the excellent discharge tolerance. A floating strip Micromegas with an active area of 48cm$\\times$50cm with 1920 copper anode strips exhibits in 120GeV pion beams a spatial resolution of 50$\\mu$m at detection efficiencies above 95%. Pulse height, spatial resolution and detection efficiency are homogeneous over the detector. Reconstruction of particle track inclination in a single detector plane is discussed, optimum angular resolutions below $5^\\circ$ are observed. Systematic deviations of this $\\mu$TPC-method are fully understood. The reconstruction capabilities for minimum ionizing muons are investigated in a 6.4cm$\\time...

  16. 炼山造林和捡带(不炼山)造林对杉木造林成活率及生长的影响%Affect of Burning-afforestation and Non-burning-afforestation on the Plantation Survival Rate and Growth of Chinese Fir

    Institute of Scientific and Technical Information of China (English)

    黎卓林; 谢三秀

    2012-01-01

    在信丰县油山营林林场采用炼山整地挖穴造林和捡带(不炼山)整地挖穴造林以及捡带(不炼山)边挖穴边种树3种不同方式营造杉木林,进行幼树生长、成活率、保存率对比试验。结果表明,在该立地条件下,不同造林方式在幼林的前两年对杉木幼树生长及成活率影响不显著。但捡带(不炼山)整地挖穴造林方式比炼山整地挖穴和捡带(不炼山)边挖穴边种两种处理费用分别高出25%和28.6%,而炼山整地挖穴造林和捡带(不炼山)边挖边种两种处理费用基本持平。因此把造林成本、水土保持效果和森林防火风险等因素考虑进去后,捡带(不炼山)边挖边种植是一种较好的选择。%Three different afforestation ways of Chinese fir were carried out in Youshan Forest Farm of Xinfeng County as follows: controlled burning with site preparation in hole; non-burning with site preparation in hole, as well as non-burning with site preparation while planting. The comparative test on sapling growth, survival rate, preservation rate was made. The results showed that under that site conditions, different afforestation ways have not significant effect on sapling growth and survival rate of fir at the first two years. But the processing cost for the afforestation way of non-burning with site preparation in hole was higher than controlled burning with site preparation in hole and non-burning with site preparation while planting for 25% and 28.6%, respectively. So the cost of controlled burning with site preparation in hole and non-burning with site preparation while planting was basically the same. Therefore, after taking the cost of afforestation, soil and water conservation effects, forest fireproof risk and other factors into account, the way of non-burning with site preparation while planting was a better choice.

  17. High Temperature Reactor (HTR) Deep Burn Core and Fuel Analysis: Design Selection for the Prismatic Block Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Francesco Venneri; Chang-Keun Jo; Jae-Man Noh; Yonghee Kim; Claudio Filippone; Jonghwa Chang; Chris Hamilton; Young-Min Kim; Ji-Su Jun; Moon-Sung Cho; Hong-Sik Lim; MIchael A. Pope; Abderrafi M. Ougouag; Vincent Descotes; Brian Boer

    2010-09-01

    The Deep Burn (DB) Project is a U.S. Department of Energy sponsored feasibility study of Transuranic Management using high burnup fuel in the high temperature helium cooled reactor (HTR). The DB Project consists of seven tasks: project management, core and fuel analysis, spent fuel management, fuel cycle integration, TRU fuel modeling, TRU fuel qualification, and HTR fuel recycle. In the Phase II of the Project, we conducted nuclear analysis of TRU destruction/utilization in the HTR prismatic block design (Task 2.1), deep burn fuel/TRISO microanalysis (Task 2.3), and synergy with fast reactors (Task 4.2). The Task 2.1 covers the core physics design, thermo-hydraulic CFD analysis, and the thermofluid and safety analysis (low pressure conduction cooling, LPCC) of the HTR prismatic block design. The Task 2.3 covers the analysis of the structural behavior of TRISO fuel containing TRU at very high burnup level, i.e. exceeding 50% of FIMA. The Task 4.2 includes the self-cleaning HTR based on recycle of HTR-generated TRU in the same HTR. Chapter IV contains the design and analysis results of the 600MWth DB-HTR core physics with the cycle length, the average discharged burnup, heavy metal and plutonium consumptions, radial and axial power distributions, temperature reactivity coefficients. Also, it contains the analysis results of the 450MWth DB-HTR core physics and the analysis of the decay heat of a TRU loaded DB-HTR core. The evaluation of the hot spot fuel temperature of the fuel block in the DB-HTR (Deep-Burn High Temperature Reactor) core under full operating power conditions are described in Chapter V. The investigated designs are the 600MWth and 460MWth DB-HTRs. In Chapter VI, the thermo-fluid and safety of the 600MWth DB-HTRs has been analyzed to investigate a thermal-fluid design performance at the steady state and a passive safety performance during an LPCC event. Chapter VII describes the analysis results of the TRISO fuel microanalysis of the 600MWth and 450

  18. High dose rate brachytherapy source measurement intercomparison.

    Science.gov (United States)

    Poder, Joel; Smith, Ryan L; Shelton, Nikki; Whitaker, May; Butler, Duncan; Haworth, Annette

    2017-06-01

    This work presents a comparison of air kerma rate (AKR) measurements performed by multiple radiotherapy centres for a single HDR (192)Ir source. Two separate groups (consisting of 15 centres) performed AKR measurements at one of two host centres in Australia. Each group travelled to one of the host centres and measured the AKR of a single (192)Ir source using their own equipment and local protocols. Results were compared to the (192)Ir source calibration certificate provided by the manufacturer by means of a ratio of measured to certified AKR. The comparisons showed remarkably consistent results with the maximum deviation in measurement from the decay-corrected source certificate value being 1.1%. The maximum percentage difference between any two measurements was less than 2%. The comparisons demonstrated the consistency of well-chambers used for (192)Ir AKR measurements in Australia, despite the lack of a local calibration service, and served as a valuable focal point for the exchange of ideas and dosimetry methods.

  19. Curbing Inflammation in Burn Patients

    Directory of Open Access Journals (Sweden)

    Jayme A. Farina

    2013-01-01

    Full Text Available Patients who suffer from severe burns develop metabolic imbalances and systemic inflammatory response syndrome (SIRS which can result in multiple organ failure and death. Research aimed at reducing the inflammatory process has yielded new insight into burn injury therapies. In this review, we discuss strategies used to curb inflammation in burn injuries and note that further studies with high quality evidence are necessary.

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

    Science.gov (United States)

    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...

  1. Liquid argon calorimeter performance at high rates

    CERN Document Server

    Seifert, F; The ATLAS collaboration

    2012-01-01

    The expected increase of luminosity at HL-LHC by a factor of ten with respect to LHC luminosities has serious consequences for the signal reconstruction, radiation hardness requirements and operations of the ATLAS liquid argon calorimeters in the endcap, respectively forward region. Small modules of each type of calorimeter have been built and exposed to a high intensity proton beam of 50 GeV at IHEP/Protvino. The beam is extracted via the bent crystal technique, offering the unique opportunity to cover intensities ranging from $10^6$ p/s up to $10^{12}$ p/s. This exceeds the deposited energy per time expected at HL-LHC by more than a factor of 100. The correlation between beam intensity and the read-out signal has been studied. The data show clear indications of pulse shape distortion due to the high ionization build-up, in agreement with MC expectations. This is also confirmed from the dependence of the HV currents on beam intensity.

  2. Liquid Argon Calorimeter performance at High Rates

    CERN Document Server

    Seifert, F; The ATLAS collaboration

    2013-01-01

    The expected increase of luminosity at HL-LHC by a factor of ten with respect to LHC luminosities has serious consequences for the signal reconstruction, radiation hardness requirements and operations of the ATLAS liquid argon calorimeters in the endcap, respectively forward region. Small modules of each type of calorimeter have been built and exposed to a high intensity proton beam of 50 GeV at IHEP/Protvino. The beam is extracted via the bent crystal technique, offering the unique opportunity to cover intensities ranging from $10^6$ p/s up to $3\\cdot10^{11}$ p/s. This exceeds the deposited energy per time expected at HL-LHC by more than a factor of 100. The correlation between beam intensity and the read-out signal has been studied. The data show clear indications of pulse shape distortion due to the high ionization build-up, in agreement with MC expectations. This is also confirmed from the dependence of the HV currents on beam intensity.

  3. High-deposition-rate ceramics synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Allendorf, M.D.; Osterheld, T.H.; Outka, D.A. [Sandia National Laboratories, Livermore, CA (United States)] [and others

    1995-05-01

    Parallel experimental and computational investigations are conducted in this project to develop validated numerical models of ceramic synthesis processes. Experiments are conducted in the High-Temperature Materials Synthesis Laboratory in Sandia`s Combustion Research Facility. A high-temperature flow reactor that can accommodate small preforms (1-3 cm diameter) generates conditions under which deposition can be observed, with flexibility to vary both deposition temperature (up to 1500 K) and pressure (as low as 10 torr). Both mass spectrometric and laser diagnostic probes are available to provide measurements of gas-phase compositions. Experiments using surface analytical techniques are also applied to characterize important processes occuring on the deposit surface. Computational tools developed through extensive research in the combustion field are employed to simulate the chemically reacting flows present in typical industrial reactors. These include the CHEMKIN and Surface-CHEMKIN suites of codes, which permit facile development of complex reaction mechanisms and vastly simplify the implementation of multi-component transport and thermodynamics. Quantum chemistry codes are also used to estimate thermodynamic and kinetic data for species and reactions for which this information is unavailable.

  4. High rate fabrication of compression molded components

    Energy Technology Data Exchange (ETDEWEB)

    Matsen, Marc R.; Negley, Mark A.; Dykstra, William C.; Smith, Glen L.; Miller, Robert J.

    2016-04-19

    A method for fabricating a thermoplastic composite component comprises inductively heating a thermoplastic pre-form with a first induction coil by inducing current to flow in susceptor wires disposed throughout the pre-form, inductively heating smart susceptors in a molding tool to a leveling temperature with a second induction coil by applying a high-strength magnetic field having a magnetic flux that passes through surfaces of the smart susceptors, shaping the magnetic flux that passes through surfaces of the smart susceptors to flow substantially parallel to a molding surface of the smart susceptors, placing the heated pre-form between the heated smart susceptors; and applying molding pressure to the pre-form to form the composite component.

  5. The modern high rate digital cassette recorder

    Science.gov (United States)

    Clemow, Martin

    1993-01-01

    The magnetic tape recorder has played an essential role in the capture and storage of instrumentation data for more than thirty years. During this time, data recording technology has steadily progressed to meet user demands for more channels, wider bandwidths, and longer recording durations. When acquisition and processing moved from analog to digital techniques, so recorder design followed suit. Milestones marking the evolution of the data recorder through these various stages - multi-track analog, high density longitudinal digital, and more recently rotary digital - have often represented important breakthroughs in the handling of ever-greater quantities of data. Throughout this period there has been a very clear line of demarcation between data storage methods in the 'instrumentation world' on the one hand and the 'computer peripheral world' on the other. This is despite the fact that instrumentation data, whether analog or digital at the point of acquisition, is now likely to be processed on a digital computer at some stage. Regardless of whether the processing device is a small personal computer, a workstation, or the largest supercomputer, system integrators have traditionally been faced with the same basic problem - how to interface what is essentially a manually controlled, continuously running device (the tape recorder) into the fast start/stop computer environment without resorting to an excessive amount of complex custom interfacing and performance compromise. The increasing availability of affordable high power processing equipment throughout the scientific world is forcing recorder manufacturers to make their latest and perhaps most important breakthrough - the computer-friendly data recorder. The operating characteristics of such recorders are discussed and the resultant impact on both data acquisition and data analysis elements of system configuration are considered.

  6. Ten-year epidemiology of chemical burns in western Zhejiang Province, China.

    Science.gov (United States)

    Ye, Chunjiang; Wang, Xingang; Zhang, Yuanhai; Ni, Liangfang; Jiang, Ruiming; Liu, Liping; Han, Chunmao

    2016-05-01

    -333 days). Surgery was performed in 146 patients (21.16%), and the overall mortality rate was 0.58%. Chemical burns are preventable. The high morbidity of chemical burns in western Zhejiang Province is related to the industrial structure of the area. Governmental management in the fields of production, transportation, and utilization of chemicals could be improved. Workplaces have the responsibility to provide safe work environments and equipment, as well as occupational education and safety training for high-risk work groups. Copyright © 2015 Elsevier Ltd and ISBI. All rights reserved.

  7. [BURNS IN ISRAEL: DEMOGRAPHIC, ETIOLOGIC AND CLINICAL FEATURES, 2004-2010].

    Science.gov (United States)

    Harats, Moti; Wiessman, Oren; Peleg, Kobi; Givon, Adi; Haik, Joseh

    2015-11-01

    The treatment of burn patients plays a major role in the health system, requiring numerous resources and extensively long hospitalizations. The treatment involves Intensive Care Units and the entire medical and para-medical staff. Currently, Israel has 5 designated burn units, strategically scattered all over the country. Recently, due to some major burn disasters, reevaluation of the demography, etiology and clinical features of burns has been conducted. The study entails quantity and quality evaluations of burn victims in Israel between the years 2004 and 2010, identification of high risk populations and recent demographic, etiological and clinical trends. A data analysis was conducted of all the burn patients hospitalized in Israel's 5 trauma centers' burn units between the years 2004 and 2010 according to the Israeli Trauma Registry (ITR). Between the years 2004 and 2010, 5270 burn victims were hospitalized in five trauma centers burn units. The average hospitalization period was 11.67 days, while the mortality rate was 3.72%. High risk populations were identified as babies up to 2 years old and the non-Jewish population. High risk populations were identified, such as young babies and the non-Jewish population. These groups should be addressed specifically with proper publicity and information. Even though mortality rates were stable, the mean hospitalization length is declining over the years, possibly secondary to advanced dressing and ambulatory treatments.

  8. High data rate optical transceiver terminal

    Science.gov (United States)

    Clarke, E. S.

    1973-01-01

    The objectives of this study were: (1) to design a 400 Mbps optical transceiver terminal to operate from a high-altitude balloon-borne platform in order to permit the quantitative evaluation of a space-qualifiable optical communications system design, (2) to design an atmospheric propagation experiment to operate in conjunction with the terminal to measure the degrading effects of the atmosphere on the links, and (3) to design typical optical communications experiments for space-borne laboratories in the 1980-1990 time frame. As a result of the study, a transceiver package has been configured for demonstration flights during late 1974. The transceiver contains a 400 Mbps transmitter, a 400 Mbps receiver, and acquisition and tracking receivers. The transmitter is a Nd:YAG, 200 Mhz, mode-locked, CW, diode-pumped laser operating at 1.06 um requiring 50 mW for 6 db margin. It will be designed to implement Pulse Quaternary Modulation (PQM). The 400 Mbps receiver utilizes a Dynamic Crossed-Field Photomultiplier (DCFP) detector. The acquisition receiver is a Quadrant Photomultiplier Tube (QPMT) and receives a 400 Mbps signal chopped at 0.1 Mhz.

  9. Single particle characterization of biomass burning organic aerosol (BBOA: evidence for non-uniform mixing of high molecular weight organics and potassium

    Directory of Open Access Journals (Sweden)

    A. K. Y. Lee

    2015-11-01

    Full Text Available Biomass burning is a major source of black carbon (BC and primary organic aerosol globally. In particular, biomass burning organic aerosol (BBOA is strongly associated with atmospheric brown carbon (BrC that absorbs near ultraviolet and visible light, resulting in significant impacts on regional visibility degradation and radiative forcing. The mixing state of BBOA can play a critical role in the prediction of aerosol optical properties. In this work, single particle measurements from a soot-particle aerosol mass spectrometer coupled with a light scattering module (LS-SP-AMS were performed to examine the mixing state of BBOA, refractory black carbon (rBC and potassium (K+, a tracer for biomass burning aerosol in an air mass influenced by aged biomass burning. Cluster analysis of single particle measurements identified five BBOA-related particle types. rBC accounted for 3–14 w.t. % of these particle types on average. Only one particle type exhibited a strong ion signal for K+, with mass spectra characterized by low molecular weight organic species. The remaining four particle types were classified based on the apparent molecular weight of the BBOA constituents. Two particle types were associated with low potassium content and significant amounts of high molecular weight (HMW organic compounds. Our observations indicate non-uniform mixing of particles within a biomass burning plume in terms of molecular weight and illustrate that HMW BBOA can be a key contributor to low-volatility BrC observed in BBOA particles.

  10. Outcomes of outpatient management of pediatric burns.

    Science.gov (United States)

    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.

  11. The Effect of Minimum Wage Rates on High School Completion

    Science.gov (United States)

    Warren, John Robert; Hamrock, Caitlin

    2010-01-01

    Does increasing the minimum wage reduce the high school completion rate? Previous research has suffered from (1. narrow time horizons, (2. potentially inadequate measures of states' high school completion rates, and (3. potentially inadequate measures of minimum wage rates. Overcoming each of these limitations, we analyze the impact of changes in…

  12. The Complete Burning of Weapons Grade Plutonium and Highly Enriched Uranium with (Laser Inertial Fusion-Fission Energy) LIFE Engine

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, J C; Diaz de la Rubia, T; Moses, E

    2008-12-23

    The National Ignition Facility (NIF) project, a laser-based Inertial Confinement Fusion (ICF) experiment designed to achieve thermonuclear fusion ignition and burn in the laboratory, is under construction at the Lawrence Livermore National Laboratory (LLNL) and will be completed in April of 2009. Experiments designed to accomplish the NIF's goal will commence in late FY2010 utilizing laser energies of 1 to 1.3 MJ. Fusion yields of the order of 10 to 20 MJ are expected soon thereafter. Laser initiated fusion-fission (LIFE) engines have now been designed to produce nuclear power from natural or depleted uranium without isotopic enrichment, and from spent nuclear fuel from light water reactors without chemical separation into weapons-attractive actinide streams. A point-source of high-energy neutrons produced by laser-generated, thermonuclear fusion within a target is used to achieve ultra-deep burn-up of the fertile or fissile fuel in a sub-critical fission blanket. Fertile fuels including depleted uranium (DU), natural uranium (NatU), spent nuclear fuel (SNF), and thorium (Th) can be used. Fissile fuels such as low-enrichment uranium (LEU), excess weapons plutonium (WG-Pu), and excess highly-enriched uranium (HEU) may be used as well. Based upon preliminary analyses, it is believed that LIFE could help meet worldwide electricity needs in a safe and sustainable manner, while drastically shrinking the nation's and world's stockpile of spent nuclear fuel and excess weapons materials. LIFE takes advantage of the significant advances in laser-based inertial confinement fusion that are taking place at the NIF at LLNL where it is expected that thermonuclear ignition will be achieved in the 2010-2011 timeframe. Starting from as little as 300 to 500 MW of fusion power, a single LIFE engine will be able to generate 2000 to 3000 MWt in steady state for periods of years to decades, depending on the nuclear fuel and engine configuration. Because the fission

  13. Burns (For Parents)

    Science.gov (United States)

    ... Old Feeding Your 1- to 2-Year-Old Burns KidsHealth > For Parents > Burns A A A What's ... outlets, etc.) overexposure to the sun Types of Burns Burns are often categorized as first-, second-, or ...

  14. Chemical states of fission products in irradiated (U 0.3Pu 0.7)C 1+ x fuel at high burn-ups

    Science.gov (United States)

    Agarwal, Renu; Venugopal, V.

    2006-12-01

    The chemical states of fission products have been theoretically determined for the irradiated carbide fuel of Fast Breeder Test Reactor (FBTR) at Kalpakkam, India, at different burn-ups. The SOLGASMIX-PV computer code was used to determine the equilibrium chemical composition of the fuel. The system was assumed to be composed of a gaseous phase at one atmosphere pressure, and various solid phases. The distribution of elements in these phases and their chemical states at different temperatures were calculated as a function of burn-up. The FBTR fuel, (U 0.3Pu 0.7)C 1+ x, was loaded with C/M values in the range, 1.03-1.06. The present calculations indicated that even for the lowest starting C/M of 1.03 in the FBTR fuel, the liquid metal phase of (U, Pu), should not appear at a burn-up as high as 150 GWd/t.

  15. An epidemiological study of 500 paediatric burn patients in Mumbai, India

    Directory of Open Access Journals (Sweden)

    Verma S

    2007-01-01

    Full Text Available Aim: To study the epidemiological data of paediatric burn patients to determine the role of demographic distribution and epidemiological parameters for assessment of mortality rate and development of burn prevention strategy. Materials and Methods : Epidemiological data of 500 patients admitted to the Burns and Plastic Surgery Unit of B.J. Wadia Hospital, Mumbai over a period of six years (2000-2005 was reviewed from medical records. Age, sex, demographic distribution, seasonal variation, total body surface area (TBSA involved, type and place of burn injury, parental occupation, family size, first aid and mortality rate were studied. Result: Median age group for patient was 3.44 years (range one month to 14 years. The majority (24% of burns occurred in children between the one to two years age group. Male to female sex ratio was 1.38:1. Most of the patients were from the defined demographic region served by the hospital. A significant number of patients however were from outside this region. Burn injury occurred predominantly during winter. Most common type of burn was scalds which occurred mainly in domestic circumstances. In the majority of patients, less than 10% TBSA was involved. All patients were managed as per the unit protocol. Mortality rate was 10.4%. Mortality rate was high in patients having more than 40% TBSA involvement. Seventy-three per cent of the total deaths occurred in the patients coming from regions outside the demographic region served by the hospital. Parental occupation, family size and the first aid did not affect the mortality rate. Conclusion: Availability of a burn care unit in the vicinity can decrease the mortality rates in the paediatric burn patients. An intense and focused burn prevention campaign to educate the general population about dangerous aetiological factors will decrease the incidence of paediatric burns.

  16. High regression rate, high density hybrid fuels Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR program will investigate high energy density novel nanofuels combined with high density binders for use with an N2O oxidizer. Terves has developed...

  17. Very High Temperature Reactor (VHTR) Deep Burn Core and Fuel Analysis -- Complete Design Selection for the Pebble Bed Reactor

    Energy Technology Data Exchange (ETDEWEB)

    B. Boer; A. M. Ougouag

    2010-09-01

    The Deep-Burn (DB) concept focuses on the destruction of transuranic nuclides from used light water reactor fuel. These transuranic nuclides are incorporated into TRISO coated fuel particles and used in gas-cooled reactors with the aim of a fractional fuel burnup of 60 to 70% in fissions per initial metal atom (FIMA). This high performance is expected through the use of multiple recirculation passes of the fuel in pebble form without any physical or chemical changes between passes. In particular, the concept does not call for reprocessing of the fuel between passes. In principle, the DB pebble bed concept employs the same reactor designs as the presently envisioned low-enriched uranium core designs, such as the 400 MWth Pebble Bed Modular Reactor (PBMR-400). Although it has been shown in the previous Fiscal Year (2009) that a PuO2 fueled pebble bed reactor concept is viable, achieving a high fuel burnup, while remaining within safety-imposed prescribed operational limits for fuel temperature, power peaking and temperature reactivity feedback coefficients for the entire temperature range, is challenging. The presence of the isotopes 239-Pu, 240-Pu and 241-Pu that have resonances in the thermal energy range significantly modifies the neutron thermal energy spectrum as compared to a ”standard,” UO2-fueled core. Therefore, the DB pebble bed core exhibits a relatively hard neutron energy spectrum. However, regions within the pebble bed that are near the graphite reflectors experience a locally softer spectrum. This can lead to power and temperature peaking in these regions. Furthermore, a shift of the thermal energy spectrum with increasing temperature can lead to increased absorption in the resonances of the fissile Pu isotopes. This can lead to a positive temperature reactivity coefficient for the graphite moderator under certain operating conditions. The effort of this task in FY 2010 has focused on the optimization of the core to maximize the pebble discharge

  18. Impact of Turbulence Intensity and Equivalence Ratio on the Burning Rate of Premixed Methane–Air Flames

    Directory of Open Access Journals (Sweden)

    Gábor Janiga

    2011-05-01

    Full Text Available Direct Numerical Simulations (DNS have been conducted to study the response of initially laminar spherical premixed methane–air flame kernels to successively higher turbulence intensities at five different equivalence ratios. The numerical experiments include a 16-species/25-step skeletal mechanism for methane oxidation and a multicomponent molecular transport model. Highly turbulent conditions (with integral Reynolds numbers up to 4513 have been accessed. The effect of turbulence on the physical properties of the flame, in particular its consumption speed Sc, which is an interesting measure of the turbulent flame speed ST has been investigated. Local quenching events are increasingly observed for highly turbulent conditions, particularly for lean mixtures. The obtained results qualitatively confirm the expected trend regarding correlations between u′/SL and the consumption speed: Sc first increases, roughly linearly, with u′/SL (low turbulence zone, then levels off (bending zone before decreasing again (quenching limit for too intense turbulence. For a fixed value of u′/SL, Sc/SL varies with the mixture equivalence ratio, showing that additional parameters should probably enter phenomenological expressions relating these two quantities.

  19. The effect of dissolved hydrogen on the dissolution of {sup 233}U doped UO{sub 2}(s) high burn-up spent fuel and MOX fuel

    Energy Technology Data Exchange (ETDEWEB)

    Carbol, P. [Inst. for Transuranium Elements, Karlsruhe (Germany); Spahiu, K. (ed.) [and others

    2005-03-01

    In this report the results of the experimental work carried out in a large EU-research project (SFS, 2001-2004) on spent fuel stability in the presence of various amounts of near field hydrogen are presented. Studies of the dissolution of {sup 233}U doped UO{sub 2}(s) simulating 'old' spent fuel were carried out as static leaching tests, autoclave tests with various hydrogen concentrations and electrochemical tests. The results of the leaching behaviour of a high burn-up spent fuel pellet in 5 M NaCl solutions in the presence of 3.2 bar H{sub 2} pressure and of MOX fuel in dilute synthetic groundwater under 53 bar H{sub 2} pressure are also presented. In all the experimental studies carried out in this project, a considerable effect of hydrogen in the dissolution rates of radioactive materials was observed. The experimental results obtained in this project with a-doped UO{sub 2}, high burn-up spent fuel and MOX fuel together with literature data give a reliable background to use fractional alteration/dissolution rates for spent fuel of the order of 10{sup -6}/yr - 10{sup -8}/yr with a recommended value of 4x10{sup -7}/yr for dissolved hydrogen concentrations above 10{sup -3} M and Fe(II) concentrations typical for European repository concepts. Finally, based on a review of the experimental data and available literature data, potential mechanisms of the hydrogen effect are also discussed. The work reported in this document was performed as part of the Project SFS of the European Commission 5th Framework Programme under contract no FIKW-CT-2001-20192 SFS. It represents the deliverable D10 of the experimental work package 'Key experiments using a-doped UO{sub 2} and real spent fuel', coordinated by SKB with the participation of ITU, FZK-INE, ENRESA, CIEMAT, ARMINES-SUBATECH and SKB.

  20. Strain rate effect in high-speed wire drawing process

    Science.gov (United States)

    He, S.; Van Houtte, P.; Van Bael, A.; Mei, F.; Sarban, A.; Boesman, P.; Galvez, F.; Atienza, J. M.

    2002-05-01

    This paper presents a study on the strain rate effect during high-speed wire drawing process by means of finite element simulation. Based on the quasistatic stresses obtained by normal tensile tests and dynamic stresses at high strain rates by split Hopkinson pressure bar tests, the wire drawing process was simulated for low carbon steel and high carbon steel. The results show that both the deformation process and the final properties of drawn wires are influenced by the strain rate.

  1. High-Rate Strong-Signal Quantum Cryptography

    Science.gov (United States)

    Yuen, Horace P.

    1996-01-01

    Several quantum cryptosystems utilizing different kinds of nonclassical lights, which can accommodate high intensity fields and high data rate, are described. However, they are all sensitive to loss and both the high rate and the strong-signal character rapidly disappear. A squeezed light homodyne detection scheme is proposed which, with present-day technology, leads to more than two orders of magnitude data rate improvement over other current experimental systems for moderate loss.

  2. Single Longitudinal Mode, High Repetition Rate, Q-switched Ho:YLF Laser for Remote Sensing

    Science.gov (United States)

    Bai, Yingxin; Yu, Jirong; Petzar, Paul; Petros, M.; Chen, Songsheng; Trieu, Bo; Lee, Nyung; Singh, U.

    2009-01-01

    Ho:YLF/LuLiF lasers have specific applications for remote sensing such as wind-speed measurement and carbon dioxide (CO2) concentration measurement in the atmosphere because the operating wavelength (around 2 m) is located in the eye-safe range and can be tuned to the characteristic lines of CO2 absorption and there is strong backward scattering signal from aerosol (Mie scattering). Experimentally, a diode pumped Ho:Tm:YLF laser has been successfully used as the transmitter of coherent differential absorption lidar for the measurement of with a repetition rate of 5 Hz and pulse energy of 75 mJ [1]. For highly precise CO2 measurements with coherent detection technique, a laser with high repetition rate is required to averaging out the speckle effect [2]. In addition, laser efficiency is critically important for the air/space borne lidar applications, because of the limited power supply. A diode pumped Ho:Tm:YLF laser is difficult to efficiently operate in high repetition rate due to the large heat loading and up-conversion. However, a Tm:fiber laser pumped Ho:YLF laser with low heat loading can be operated at high repetition rates efficiently [3]. No matter whether wind-speed or carbon dioxide (CO2) concentration measurement is the goal, a Ho:YLF/LuLiF laser as the transmitter should operate in a single longitudinal mode. Injection seeding is a valid technique for a Q-switched laser to obtain single longitudinal mode operation. In this paper, we will report the new results for a single longitudinal mode, high repetition rate, Q-switched Ho:YLF laser. In order to avoid spectral hole burning and make injection seeding easier, a four mirror ring cavity is designed for single longitudinal mode, high repetition rate Q-switched Ho:YLF laser. The ramp-fire technique is chosen for injection seeding.

  3. Object-based assessment of burn severity in diseased forests using high-spatial and high-spectral resolution MASTER airborne imagery

    Science.gov (United States)

    Chen, Gang; Metz, Margaret R.; Rizzo, David M.; Dillon, Whalen W.; Meentemeyer, Ross K.

    2015-04-01

    Forest ecosystems are subject to a variety of disturbances with increasing intensities and frequencies, which may permanently change the trajectories of forest recovery and disrupt the ecosystem services provided by trees. Fire and invasive species, especially exotic disease-causing pathogens and insects, are examples of disturbances that together could pose major threats to forest health. This study examines the impacts of fire and exotic disease (sudden oak death) on forests, with an emphasis on the assessment of post-fire burn severity in a forest where trees have experienced three stages of disease progression pre-fire: early-stage (trees retaining dried foliage and fine twigs), middle-stage (trees losing fine crown fuels), and late-stage (trees falling down). The research was conducted by applying Geographic Object-Based Image Analysis (GEOBIA) to MASTER airborne images that were acquired immediately following the fire for rapid assessment and contained both high-spatial (4 m) and high-spectral (50 bands) resolutions. Although GEOBIA has gradually become a standard tool for analyzing high-spatial resolution imagery, high-spectral resolution data (dozens to hundreds of bands) can dramatically reduce computation efficiency in the process of segmentation and object-based variable extraction, leading to complicated variable selection for succeeding modeling. Hence, we also assessed two widely used band reduction algorithms, PCA (principal component analysis) and MNF (minimum noise fraction), for the delineation of image objects and the subsequent performance of burn severity models using either PCA or MNF derived variables. To increase computation efficiency, only the top 5 PCA and MNF and top 10 PCA and MNF components were evaluated, which accounted for 10% and 20% of the total number of the original 50 spectral bands, respectively. Results show that if no band reduction was applied the models developed for the three stages of disease progression had relatively

  4. The Application of Erosive Burning to Propellant Charge Interior Ballistics

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hong-lin

    2009-01-01

    Erosive burning is a common burning phenomenon of the gunpowder with inner holes. The actual combustion law of the gunpowder with inner holes can be changed by erosive burning. Pressure difference between the inner and the outer of hole caused by loading density variation of the propellant charge makes erosive burning occur at inner holes during in-bore burning. The effect of erosive burning on burning speed of the propellant is studied by using the effects of flow rate, heat transfer and erosion of the combustion gas in inner holes on burning rate. The mathematic model of erosive burning of the propellant is established. The effects of the factors such as loading density, inner hole size and grain length on erosive burning and interior ballistic performance are analyzed .The method to improve the bore pressure for small charge mass and small firing range by erosive burning is proposed.

  5. Burn prevention mechanisms and outcomes: pitfalls, failures and successes.

    Science.gov (United States)

    Atiyeh, Bishara S; Costagliola, Michel; Hayek, Shady N

    2009-03-01

    -risk groups. Depending on the population of the country, burns prevention could be a national programme. This can ensure sufficient funds are available and lead to proper coordination of district, regional, and tertiary care centres. It could also provide for compulsory reporting of all burn admissions to a central registry, and these data could be used to evaluate strategies and prevention programmes that should be directed at behavioural and environmental changes which can be easily adopted into lifestyle. Particularly in LMICs, the emphasis in burn prevention should be by advocating change from harmful cultural practices. This needs to be done with care and sensitivity. The present review is a summary of what has already been accomplished in terms of burn prevention highlighting some of the successes but above all the numerous pitfalls and failures. Recognizing these failures is the first step towards development of more effective burn prevention strategies particularly in LMICs in which burn injury remains endemic and associated with a high mortality rate. Burn prevention is not easy, but easy or not, we have no options; burns must be prevented.

  6. In Developping a Bench-Scale Circulating Fluidized Bed Combustor to Burn High Ash Brazilian Coal-Dolomites Mixtures

    Science.gov (United States)

    Ramírez Behainne, Jhon Jairo; Hory, Rogério Ishikawa; Goldstein, Leonardo; Bernárdez Pécora, Araí Augusta

    This work considers some of the questions in burning high ash Brazilian coal-dolomite mixtures in a bench-scale circulating fluidized bed combustor (CFBC). Experimental tests were performed with the CE4500 coal from Santa Catarina State, in southern Brazil, with a Sauter mean diameter d p =43 μm. The coal particles were mixed with dolomite particles of d p = 111 μm and this fuel mixture was fed into the circulating fluidized reactor, previously loaded with quartz sand particles of d p =353 μm. This inert material was previously heated by the combustion of liquefied petroleum gas up to the ignition temperature of the fuel mixture. The CFBC unit has a 100mm internal diameter riser, 4.0m high, as well as a 62.8mm internal diameter downcomer. The loop has a cyclone, a sampling valve to collect particles and a 62.8mm internal diameter L-valve to recirculate the particles in the loop. A screw feeder with a rotation control system was used to feed the fuel mixture to the reactor. The operational conditions were monitored by pressure taps and thermocouples installed along the loop. A data acquisition system showed the main operational conditions to control. Experimental tests performed put in evidence the problems found during bed operation, with special attention to the solids feed device, to the L-valve operation, to particle size, solids inventory, fluidized gas velocity, fuel mixture and recirculated solids feeding positions.

  7. Research into the prevention and treatment of burns due to specific causes should be highly strengthened%特殊原因烧伤的防治研究不容忽视

    Institute of Scientific and Technical Information of China (English)

    谢卫国

    2012-01-01

    So far there is no clear and accurate definition for burns due to specific causes,though they are encountered sometimes.Burns due to specific causes sometimes are neglected because of their low incidence,and many surgeons,even burn specialists are not familiar with them because of low incidence,thus leading to poor results in the treatment.Burns due to specific causes are often involved in complicated and compound injuries.The treatment is often difficult,leading to delayed wound healing.In this paper,the definition,classification,and clinical characteristics of burns due to specific causes are described.Problems involved in diagnosis and treatment of common ones such as electrical,chemical,and compound burns are discussed.Facing an increase of those bums with specific causes,the author suggests that the research into the prevention and treatment should be highly strengthened.

  8. Burning vasculitis.

    Science.gov (United States)

    Chadha, Priyanka; Hobday, Dorian; O'Connor, Edmund Fitzgerald; D'Cruz, David

    2016-04-26

    We present the case of a 69-year-old man who was found collapsed close to a heat source and admitted to hospital for severe sepsis. He was also found to have widespread blistering and ulceration of his right leg; however, a history was unobtainable due to reduced consciousness levels. The leg lesions had the initial appearance of mixed depth burns and a management plan was made to transfer the patient to a burns unit for debridement. It was subsequently noted that the patient had a previous diagnosis of seropositive erosive rheumatoid arthritis. A biopsy of the leg lesion was performed and a diagnosis of rheumatoid vasculitis confirmed. Treatment with systemic steroids, intravenous antibiotics and intravenous immunoglobulin therapy for severe hypogammaglobulinaemia was started, and the patient was not transferred for surgical debridement. Rheumatoid vasculitis is a rare and extremely serious complication of rheumatoid arthritis that can manifest in a number of ways, occasionally mimicking other conditions. This case is essential to raise awareness of rare, severe rheumatoid vasculitis and of the potential for its misdiagnosis as a mixed depth burn.

  9. High Blood Pressure Rates Have Doubled Worldwide Since 1975

    Science.gov (United States)

    ... https://medlineplus.gov/news/fullstory_162069.html High Blood Pressure Rates Have Doubled Worldwide Since 1975 Most of ... News) -- The number of people worldwide with high blood pressure has nearly doubled over the past 40 years, ...

  10. Analysis of predictor factors of limb amputation in patients with high-voltage electrical burns

    OpenAIRE

    2015-01-01

    Background: Limb amputation is considered one of the most devastating consequences of electrical injury. Any factors that correlate with the degree of muscle damage can be used to predict the necessity of limb amputation. The aim of this study was to determine the factors that can be used to predict limb amputation in high-voltage electrically injured patients. Methods: Eighty-two high-voltage electrically injured patients were admitted to the Department of Plastic and Reconstructive Surg...

  11. Microskin autografting in the treatment of burns over 70% of total body surface area: 14 years of clinical experience.

    Science.gov (United States)

    Chen, Xu-Lin; Liang, Xun; Sun, Li; Wang, Fei; Liu, Sheng; Wang, Yong-Jie

    2011-09-01

    Despite the fact that early excision and grafting have significantly improved burn outcomes, the management of severely burned patients whose burn size exceeds 70% total body surface area (TBSA) still represents a big challenge for burn surgeons all over the world. During the period of 1997-2010 at our centre, aggressive excision and microskin autografting were performed in 63 severely burned patients. Their burn sizes ranged from 70% to 98% TBSA with a mean of 84.9%. The average full-thickness burn was 66.3% (range, 29-94%). Thirty patients had concomitant inhalation injury. Two to 7 days after burn, these patients underwent aggressive excisions ranging from 25% to 60% TBSA and transplantation of microskin autograft overlaid with allograft. The ratios of donor-site to recipient-site surface area were between 1:6 and 1:18. Signs of epithelialization were shown within 35-55 days. The wound healing rate was 74.9% (176/235), with 51.1% of cases (120/235) healing completely and 23.8% (56/235) improving. Microskin autografting yielded an overall survival rate of 63.5%; only 23 patients died. Our clinical experience in using the microskin autografting for burn coverage suggests that the technique is very effective in covering extensive burns, and that it is particularly useful when graft donor sites are very limited due to its high utilization rate of donor site. The factors affecting the outcome of microskin autografting are discussed herein.

  12. A comparative study of the ignition and burning characteristics of after burning aluminum and magnesium particles

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Ji Hwan; Lee, Sang Hyup; Yoon, Woong Sup [Yonsei University, Seoul (Korea, Republic of)

    2014-10-15

    Ignition and the burning of air-born single aluminum and magnesium particles are experimentally investigated. Particles of 30 to 106 μm-diameters were electrodynamically levitated, ignited, and burnt in atmospheric air. The particle combustion evolution was recorded by high-speed cinematography. Instant temperature and thermal radiation intensity were measured using two-wavelength pyrometry and photomultiplier tube methods. Ignition of the magnesium particle is prompt and substantially advances the aluminum particle by 10 ms. Burning time of the aluminum particles is extended 3 to 5 times longer than the magnesium particles. Exponents of a power-law fit of the burning rates are 1.55 and 1.24 for aluminum and magnesium particles, respectively. Flame temperature is slightly lower than the oxide melting temperature. For the aluminum, dimensionless flame diameter is inert to the initial particle size, but for the magnesium inversely proportional to the initial diameter.

  13. High-shear-rate capillary viscometer for inkjet inks

    Energy Technology Data Exchange (ETDEWEB)

    Wang Xi [FUJIFILM Dimatix, Inc., Lebanon, New Hampshire 03766 (United States); Carr, Wallace W.; Bucknall, David G. [School of Polymer, Textile, and Fiber Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Morris, Jeffrey F. [Department of Chemical Engineering and Benjamin Levich Institute for Physico-Chemical Hydrodynamics, City College of New York, New York, New York 10031 (United States)

    2010-06-15

    A capillary viscometer developed to measure the apparent shear viscosity of inkjet inks at high apparent shear rates encountered during inkjet printing is described. By using the Weissenberg-Rabinowitsch equation, true shear viscosity versus true shear rate is obtained. The device is comprised of a constant-flow generator, a static pressure monitoring device, a high precision submillimeter capillary die, and a high stiffness flow path. The system, which is calibrated using standard Newtonian low-viscosity silicone oil, can be easily operated and maintained. Results for measurement of the shear-rate-dependent viscosity of carbon-black pigmented water-based inkjet inks at shear rates up to 2x10{sup 5} s{sup -1} are discussed. The Cross model was found to closely fit the experimental data. Inkjet ink samples with similar low-shear-rate viscosities exhibited significantly different shear viscosities at high shear rates depending on particle loading.

  14. Circuit and interconnect design for high bit-rate applications

    NARCIS (Netherlands)

    Veenstra, H.

    2006-01-01

    This thesis presents circuit and interconnect design techniques and design flows that address the most difficult and ill-defined aspects of the design of ICs for high bit-rate applications. Bottlenecks in interconnect design, circuit design and on-chip signal distribution for high bit-rate applicati

  15. High Graduate Unemployment Rate and Taiwanese Undergraduate Education

    Science.gov (United States)

    Wu, Chih-Chun

    2011-01-01

    An expansion in higher education in combination with the recent global economic recession has resulted in a high college graduate unemployment rate in Taiwan. This study investigates how the high unemployment rate and financial constraints caused by economic cutbacks have shaped undergraduates' class choices, job needs, and future income…

  16. HIGH-RATE DISINFECTION TECHNIQUES FOR COMBIND SEWER OVERFLOW

    Science.gov (United States)

    This paper presents high-rate disinfection technologies for combined sewer overflow (CSO). The high-rate disinfection technologies of interest are: chlorination/dechlorination, ultraviolet light irradiation (UV), chlorine dioxide (ClO2 ), ozone (O3), peracetic acid (CH3COOOH )...

  17. A modified surgical technique in the management of eyelid burns: a case series

    Directory of Open Access Journals (Sweden)

    Sun Shudong

    2011-08-01

    Full Text Available Abstract Introduction Contractures, ectropion and scarring, the most common sequelae of skin grafts after eyelid burn injuries, can result in corneal exposure, corneal ulceration and even blindness. Split-thickness or full-thickness skin grafts are commonly used for the treatment of acute eyelid burns. Plasma exudation and infection are common early complications of eyelid burns, which decrease the success rate of grafts. Case presentation We present the cases of eight patients, two Chinese women and six Chinese men. The first Chinese woman was 36 years old, with 70% body surface area second or third degree flame burn injuries involving her eyelids on both sides. The other Chinese woman was 28 years old, with sulfuric acid burns on her face and third degree burn on her eyelids. The six Chinese men were aged 21, 31, 38, 42, 44, and 55 years, respectively. The 38-year-old patient was transferred from the ER with 80% body surface area second or third degree flame burn injuries and third degree burn injuries to his eyelids. The other five men were all patients with flame burn injuries, with 7% to 10% body surface area third degree burns and eyelids involved. All patients were treated with a modified surgical procedure consisting of separation and loosening of the musculus orbicularis oculi between tarsal plate and septum orbital, followed by grafting a large full-thickness skin graft in three days after burn injury. The use of our modified surgical procedure resulted in 100% successful eyelid grafting on first attempt, and all our patients were in good condition at six-month follow-up. Conclusions This new surgical technique is highly successful in treating eyelid burn injuries, especially flame burn injuries of the eyelid.

  18. High Job Demands, Still Engaged and Not Burned Out? The Role of Job Crafting

    NARCIS (Netherlands)

    Hakanen, Jari J.; Seppälä, Piia; Peeters, Maria C W

    2017-01-01

    Purpose: Traditionally, employee well-being has been considered as resulting from decent working conditions arranged by the organization. Much less is known about whether employees themselves can make self-initiated changes to their work, i.e., craft their jobs, in order to stay well, even in highly

  19. High frequency of multidrug-resistant Staphylococcus aureus with SCCmec type III and Spa types t037 and t631 isolated from burn patients in southwest of Iran.

    Science.gov (United States)

    Parhizgari, Najmeh; Khoramrooz, Seyed Sajjad; Malek Hosseini, Seyed Ali Asghar; Marashifard, Masoud; Yazdanpanah, Mahboobeh; Emaneini, Mohammad; Gharibpour, Farzaneh; Mirzaii, Mehdi; Darban-Sarokhalil, Davood; Moein, Masoud; Naraki, Mahmood

    2016-03-01

    Methicilin resistance Staphylococcus aureus (MRSA) infections are the major challenges in hospitals, especially in the burn units. The use of molecular typing methods is essential for tracking the spread of S. aureus infection and epidemiological investigations. The aim of this study was to find the profile of the spa types and also the prevalence of each SCCmec type of S. aureus strains in a central burn hospital in southwest of Iran. A total of 81 non-duplicate S. aureus were isolated from burn patients between April 2011 and February 2012. The susceptibility of the isolates against 13 different antibiotics was tested by disk agar diffusion (DAD) method. MRSA strains were identified by amplification of mecA gene. Multiplex-polymerase chain reaction (PCR) technique was used to determine the SCCmec types of MRSA strains and all the S. aureus isolates were typed by spa typing method. Detection of mecA gene showed that 70 (86.4%) of the isolates were MRSA. The highest rate of resistance was observed for penicillin (97.5%) and erythromycin (77.8%). None of the isolates were resistant to vancomycin. Sixty-seven of the 70 MRSA isolates harbored only SCCmec type III and three untypeable isolates. Five different spa types were detected. The most common spa types were t037 (42.5%) and t631 (34.5%) and were only found in MRSA isolates. Only SCCmec type III was found in burn patients which emphasizes the HA-MRSA origin of these strains. Only five different spa types identified in this study are in accordance with one SCCmec type which indicates that a limited number of bacterial colons are circulated in the burn unit in this hospital.

  20. High-cooling-efficiency cryogenic quadrupole ion trap and UV-UV hole burning spectroscopy of protonated tyrosine

    Science.gov (United States)

    Ishiuchi, Shun-ichi; Wako, Hiromichi; Kato, Daichi; Fujii, Masaaki

    2017-02-01

    The cooling efficiency of a cryogenic three-dimensional quadrupole ion trap (QIT) is drastically improved by using copper electrodes instead of conventional stainless-steel ones. The temperature of trapped ions (protonated tyrosine TyrH+) was estimated based on the ultraviolet (UV) photo-dissociation spectra. The UV spectrum of TryH+ shows almost no hot bands, and thus the high cooling efficiency of the copper ion trap was proven. The temperature was also estimated by simulating the observed band contour in the UV spectra, which is determined by the population in the rotationally excited levels. From the simulations, the temperature of TryH+ was estimated to be ∼13 K, while that in the stainless-steel QIT was 45-50 K. In addition, to demonstrate the advantage of the copper QIT, UV-UV hole burning (HB) spectra, i.e. conformation-selected UV spectra, were measured. It was confirmed that four different conformers, A∼D, coexist in the ultra-cold protonated tyrosine. By comparing with the calculated Franck-Condon spectra, their structural assignments were discussed, including the orientation of the OH group.

  1. The mechanism of burn-in loss in a high efficiency polymer solar cell

    Energy Technology Data Exchange (ETDEWEB)

    Peters, Craig H.; Sachs-Quintana, I.T.; Mateker, William R.; Heumueller, Thomas; Rivnay, Jonathan; Beiley, Zach M.; Salleo, Alberto; McGehee, Michael D. [Department of Materials Science and Engineering, Stanford University, CA (United States); Noriega, Rodigo; Hoke, Eric T. [Department of Applied Physics, Stanford University, CA (United States)

    2012-02-02

    Degradation in a high efficiency polymer solar cell is caused by the formation of states in the bandgap. These states increase the energetic disorder in the system. The power conversion efficiency loss does not occur when current is run through the device in the dark but occurs when the active layer is photo-excited. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  2. The Mechanism of Burn-in Loss in a High Efficiency Polymer Solar Cell

    KAUST Repository

    Peters, Craig H.

    2011-10-11

    Degradation in a high efficiency polymer solar cell is caused by the formation of states in the bandgap. These states increase the energetic disorder in the system. The power conversion efficiency loss does not occur when current is run through the device in the dark but occurs when the active layer is photo-excited. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Occupational burns treated in emergency departments.

    Science.gov (United States)

    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.

  4. Proposing "the burns suite" as a novel simulation tool for advancing the delivery of burns education.

    Science.gov (United States)

    Sadideen, Hazim; Wilson, David; Moiemen, Naiem; Kneebone, Roger

    2014-01-01

    Educational theory highlights the importance of contextualized simulation for effective learning. We explored this concept in a burns scenario in a novel, low-cost, high-fidelity, portable, immersive simulation environment (referred to as distributed simulation). This contextualized simulation/distributed simulation combination was named "The Burns Suite" (TBS). A pediatric burn resuscitation scenario was selected after high trainee demand. It was designed on Advanced Trauma and Life Support and Emergency Management of Severe Burns principles and refined using expert opinion through cognitive task analysis. TBS contained "realism" props, briefed nurses, and a simulated patient. Novices and experts were recruited. Five-point Likert-type questionnaires were developed for face and content validity. Cronbach's α was calculated for scale reliability. Semistructured interviews captured responses for qualitative thematic analysis allowing for data triangulation. Twelve participants completed TBS scenario. Mean face and content validity ratings were high (4.6 and 4.5, respectively; range, 4-5). The internal consistency of questions was high. Qualitative data analysis revealed that participants felt 1) the experience was "real" and they were "able to behave as if in a real resuscitation environment," and 2) TBS "addressed what Advanced Trauma and Life Support and Emergency Management of Severe Burns didn't" (including the efficacy of incorporating nontechnical skills). TBS provides a novel, effective simulation tool to significantly advance the delivery of burns education. Recreating clinical challenge is crucial to optimize simulation training. This low-cost approach also has major implications for surgical education, particularly during increasing financial austerity. Alternative scenarios and/or procedures can be recreated within TBS, providing a diverse educational immersive simulation experience.

  5. Acute Kidney Injury and Renal Replacement Therapy in Burns

    Directory of Open Access Journals (Sweden)

    Burak Canver

    2011-07-01

    Full Text Available Acute kidney injury (AKI is a common complication in patients with severe burn injury and one of the major causes of death. It has a negative prognostic value and almost always develops in the context of multiple organ dysfunction syndrome (MODS induced by sepsis. Over the last 20 years, according to data avaliable, the mortality rate has been reported to reach about 75%. Several definitions of AKI have been used , but nowadays the RIFLE classification is considered the gold standard, enabling a more objective comparison of populations. There are several ways to treat AKI in burn patients, including peritoneal dialysis (PD, intermittent hemodialysis, and continuous renal replacement therapy (CRRT. CRRT is generally used in patients in whom intermittent hemodialysis has failed to control hypovolemia, as well as in patients who cannot tolerate intermittent hemodialysis. Additionally, PD is not suitable for patients with burns within the abdominal area. For these reasons, most patients with unstable hemodynamic conditions receive CRRT. In burn patients with acute renal failure the dialytic treatment with continuous renal replacement therapies permitted us to achieve a survival and dialytic adequacy; however, mortality rate is high and related to septic shock and MODS. Despite the wide variation of the analysed burn populations and definitions of AKI, this review clearly showed that AKI remains prevalent and is associated with increased mortality in patients with severe burn injury. (Journal of the Turkish Society Intensive Care 2011; 9 Suppl: 46-50

  6. Miniature High Stability High Temperature Space Rated Blackbody Radiance Source

    Science.gov (United States)

    Jones, J. A.; Beswick, A. G.

    1987-09-01

    This paper presents the design and test performance of a conical cavity type blackbody radiance source that will meet the requirements of the Halogen Occultation Experiment (HALOE) on the NASA Upper Atmospheric Research Satellite program (UARS). Since a radiance source meeting the requirements of this experiment was unavailable in the commercial market, a development effort was undertaken by the HALOE Project. The blackbody radiance source operates in vacuum at 1300 K + 0.5 K over any 15-minute interval, uses less than 7.5 watts of power, maintains a 49°C outer case temperature, and fits within the 2.5 x 2.5 x 3.0 inch envelope allocated inside the HALOE instrument. Also, the unit operates in air, during ground testing of the HALOE instrument, where it uses 17 watts of power with an outer case temperature of 66°C. The thrust of this design effort was to minimize the heat losses, in order to keep the power usage under 7.5 watts, and to minimize the amount of silica in the materials. Silica in the presence of the platinum heater winding used in this design would cause the platinum to erode, changing the operating temperature set-point. The design required the development of fabrication techniques which would provide very small, close tolerance parts from extremely difficult-to-machine materials. Also, a space rated ceramic core and unique, low thermal conductance, ceramic-to-metal joint was developed, tested and incorporated in this design. The completed flight qualification hardware has undergone performance, environmental and life testing. The design configuration and test results are discussed in detail in this paper.

  7. Patient safety measures in burn care: do National reporting systems accurately reflect quality of burn care?

    Science.gov (United States)

    Mandell, Samuel P; Robinson, Ellen F; Cooper, Claudette L; Klein, Matthew B; Gibran, Nicole S

    2010-01-01

    Recently, much attention has been placed on quality of care metrics and patient safety. Groups such as the University Health-System Consortium (UHC) collect and review patient safety data, monitor healthcare facilities, and often report data using mortality and complication rates as outcomes. The purpose of this study was to analyze the UHC database to determine if it differentiates quality of care across burn centers. We reviewed UHC clinical database (CDB) fields and available data from 2006 to 2008 for the burn product line. Based on the September 2008 American Burn Association (ABA) list of verified burn centers, we categorized centers as American Burn Association-verified burn centers, self-identified burn centers, and other centers that are not burn units but admit some burn patients. We compared total burn admissions, risk pool, complication rates, and mortality rates. Overall mortality was compared between the UHC and National Burn Repository. The UHC CDB provides fields for number of admissions, % intensive care unit admission, risk pool, length of stay, complication profiles, and mortality index. The overall numbers of burn patients in the database for the study period included 17,740 patients admitted to verified burn centers (mean 631 admissions/burn center/yr or per 2 years), 10,834 for self-identified burn centers (mean 437 admissions/burn center/yr or per 2 years), and 1,487 for other centers (mean 11.5 admissions/burn center/yr or per 2 years). Reported complication rates for verified burn centers (21.6%), self-identified burn centers (21.3%), and others (20%) were similar. Mortality rates were highest for self-identified burn centers (3.06%), less for verified centers (2.88%), and lowest for other centers (0.74%). However, these outcomes data may be misleading, because the risk pool criteria do not include burn-specific risk factors, and the inability to adjust for injury severity prevents rigorous comparison across centers. Databases such as the

  8. SEM Characterization of the High Burn-up Microstructure of U-7Mo Alloy

    Energy Technology Data Exchange (ETDEWEB)

    Dennis D. Keiser, Jr.; Jan-Fong Jue; Jian Gan; Brandon Miller; Adam Robinson; Pavel Medvedev; James Madden; Dan Wachs; M. Teague

    2014-04-01

    During irradiation, the microstructure of U-7Mo evolves until at a fission density near 5x1021 f/cm3 a high-burnup microstructure exists that is very different than what was observed at lower fission densities. This microstructure is dominated by randomly distributed, relatively large, homogeneous fission gas bubbles. The bubble superlattice has collapsed in many microstructural regions, and the fuel grain sizes, in many areas, become sub-micron in diameter with both amorphous fuel and crystalline fuel present. Solid fission product precipitates can be found inside the fission gas bubbles. To generate more information about the characteristics of the high-fission density microstructure, three samples irradiated in the RERTR-7 experiment have been characterized using a scanning electron microscope equipped with a focused ion beam. The FIB was used to generate samples for SEM imaging and to perform 3D reconstruction of the microstructure, which can be used to look for evidence of possible fission gas bubble interlinkage.

  9. Are high real interest rates bad for world economic growth?

    OpenAIRE

    1991-01-01

    There is a conventional perception that high real interest rates are bad for economic growth. However, the authors show that close examination of the experience over the last 40 years undermines the existence of such a relationship. For much of the 1950-79 period, expost real interest rates were less than the growth rate of income in the major economies, whereas the 1980s were a period of rapid growth in the world economy that coincided withunprecedentedly high real interest rates. The author...

  10. Charcoal reflectance reveals early holocene boreal deciduous forests burned at high intensities.

    Science.gov (United States)

    Hudspith, Victoria A; Belcher, Claire M; Kelly, Ryan; Hu, Feng Sheng

    2015-01-01

    Wildfire size, frequency, and severity are increasing in the Alaskan boreal forest in response to climate warming. One of the potential impacts of this changing fire regime is the alteration of successional trajectories, from black spruce to mixed stands dominated by aspen, a vegetation composition not experienced since the early Holocene. Such changes in vegetation composition may consequently alter the intensity of fires, influencing fire feedbacks to the ecosystem. Paleorecords document past wildfire-vegetation dynamics and as such, are imperative for our understanding of how these ecosystems will respond to future climate warming. For the first time, we have used reflectance measurements of macroscopic charcoal particles (>180μm) from an Alaskan lake-sediment record to estimate ancient charring temperatures (termed pyrolysis intensity). We demonstrate that pyrolysis intensity increased markedly from an interval of birch tundra 11 ky ago (mean 1.52%Ro; 485°C), to the expansion of trees on the landscape ~10.5 ky ago, remaining high to the present (mean 3.54%Ro; 640°C) irrespective of stand composition. Despite differing flammabilities and adaptations to fire, the highest pyrolysis intensities derive from two intervals with distinct vegetation compositions. 1) the expansion of mixed aspen and spruce woodland at 10 cal. kyr BP, and 2) the establishment of black spruce, and the modern boreal forest at 4 cal. kyr BP. Based on our analysis, we infer that predicted expansion of deciduous trees into the boreal forest in the future could lead to high intensity, but low severity fires, potentially moderating future climate-fire feedbacks.

  11. An attempt to reproduce high burn-up structure by ion irradiation of SIMFUEL

    Energy Technology Data Exchange (ETDEWEB)

    Baranov, V.G. [National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Kashirskoye Shosse 31, Moscow 115409 (Russian Federation); Lunev, A.V., E-mail: AVLunev@mephi.ru [National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Kashirskoye Shosse 31, Moscow 115409 (Russian Federation); Reutov, V.F. [Joint Institute for Nuclear Research (JINR), Flerov Laboratory of Nuclear Reactions (FLNR), 141980 Dubna, Moscow Region (Russian Federation); Tenishev, A.V.; Isaenkova, M.G.; Khlunov, A.V. [National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Kashirskoye Shosse 31, Moscow 115409 (Russian Federation)

    2014-09-15

    Experiments in IC-100 and U-400 cyclotrons were conducted with SIMFUEL pellets (11.47 wt.% of fission products simulators) to reproduce some aspects of the long-term irradiation conditions in epithermal reactors. Pellets were irradiated with Xe{sup 16+}, Xe{sup 24+} and He{sup +} at energies ranging from 20 keV (He{sup +}) to 320 keV (Xe{sup 16+}) and 1–90 MeV (Xe{sup 24+}). Some samples were subsequently annealed to obtain larger grain sizes and to study defects recovery. The major microstructural changes consisted in grain sub-division observed on SEM and AFM images and change in composition registered by EPMA (pellets irradiated with 1–90 MeV Xe{sup 24+} ions at fluence of 5 × 10{sup 15} cm{sup −2}). Lattice distortion and increase in dislocation density is also noted according to X-ray data. At low energies and high fluences formation of bubbles (20 keV He{sup +} at 5.5 × 10{sup 17} cm{sup −2}) was observed. Grain sub-division exhibits full coverage of the grain body and preservation of former grain boundaries. The size of sub-grains depends on local dislocation density and changes from 200 nm to 400 nm along the irradiated surface. Beneath it the size ranges from 150 to 600 nm. Sub-grains are not observed in samples irradiated by low-energy ions even at high dislocation densities.

  12. Pediatric burns due to hot water from water dispenser: a neglected issue that should be highly concerned

    Institute of Scientific and Technical Information of China (English)

    MA Bing; XI Hui-jun; WANG Jia-lin; YAN Ying; TANG Hong-tai; ZHU Shi-hui; L(U) Kai-yang; XIA Zhao-fan

    2012-01-01

    Background More and more Chinese drink hot water from water dispensers while many children were scalded due to this change.The present study aimed to propose a feasible strategy for prevention.Methods A retrospective study was conducted for all water dispensers related pediatric burns admitted to Changhai Hospital from January 2005 to December 2009.Results The number of new cases and incidences of pediatric burns due to hot water from water dispensers was significantly increasing year after year.In the total 238 involved cases,175 cases happened on males and 78.9% were at the age of 1-4 years.The burn areas were mainly located in upper extremities.All water dispensers in the surveyed families had no isolate protection devices and 85.2% of their locations were easy for children to reach.Nearly half of the children were in the same room with their guardians when injured.Total 196 burned children were playing the taps of water dispensers before injured,unfortunately,80.6% of them have not been stopped until burned.Conclusion As the kind of bums is quite serious and with bad outcome,some recommendations should be followed,such as buying water dispensers with protection devices,keeping children from touching them and so on.

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

    Science.gov (United States)

    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.

  14. First Aid: Burns

    Science.gov (United States)

    ... Your 1- to 2-Year-Old First Aid: Burns KidsHealth > For Parents > First Aid: Burns A A A Scald burns from hot water and other liquids are the most common burns in early childhood. Because burns range from mild ...

  15. First Aid: Burns

    Science.gov (United States)

    ... Old Feeding Your 8- to 12-Month-Old Feeding Your 1- to 2-Year-Old First Aid: Burns KidsHealth > For Parents > First Aid: Burns Print A A A Scald burns from hot water and other liquids are the most common burns in early childhood. Because burns range from mild to life threatening, ...

  16. High Strain Rate Compressive Tests on Woven Graphite Epoxy Composites

    Science.gov (United States)

    Allazadeh, Mohammad Reza; Wosu, Sylvanus N.

    2011-08-01

    The behavior of composite materials may be different when they are subjected to high strain rate load. Penetrating split Hopkinson pressure bar (P-SHPB) is a method to impose high strain rate on specimen in the laboratory experiments. This research work studied the response of the thin circular shape specimens, made out of woven graphite epoxy composites, to high strain rate impact load. The stress-strain relationships and behavior of the specimens were investigated during the compressive dynamic tests for strain rates as high as 3200 s-1. One dimensional analysis was deployed for analytical calculations since the experiments fulfilled the ratio of diameter to length of bars condition in impact load experiments. The mechanics of dynamic failure was studied and the results showed the factors which govern the failure mode in high strain deformation via absorbed energy by the specimen. In this paper, the relation of particle velocity with perforation depth was discussed for woven graphite epoxy specimens.

  17. Quantum data locking for high-rate private communication

    Science.gov (United States)

    Lupo, Cosmo; Lloyd, Seth

    2015-03-01

    We show that, if the accessible information is used as a security quantifier, quantum channels with a certain symmetry can convey private messages at a tremendously high rate, as high as less than one bit below the rate of non-private classical communication. This result is obtained by exploiting the quantum data locking effect. The price to pay to achieve such a high private communication rate is that accessible information security is in general not composable. However, composable security holds against an eavesdropper who is forced to measure her share of the quantum system within a finite time after she gets it.

  18. Effectiveness of high interest rate policy on exchange rates: A reexamination of the Asian financial crisis

    Directory of Open Access Journals (Sweden)

    Chin Diew Lai

    2006-09-01

    Full Text Available One of the most controversial issues in the aftermath of the Asian financial crisis has been the appropriate response of monetary policy to a sharp decline in the value of some currencies. In this paper, we empirically examine the effects on Asian exchange rates of sharply higher interest rates during the Asian financial crisis. Taking account of the currency contagion effect, our results indicate that sharply higher interest rates helped to support the exchange rates of South Korea, the Philippines, and Thailand. For Malaysia, no significant causal relation is found from the rate of interest to exchange rates, as the authorities in Malaysia did not actively adopt a high interest rate policy to defend the currency.

  19. Putative extremely high rate of proteome innovation in lancelets might be explained by high rate of gene prediction errors.

    Science.gov (United States)

    Bányai, László; Patthy, László

    2016-08-01

    A recent analysis of the genomes of Chinese and Florida lancelets has concluded that the rate of creation of novel protein domain combinations is orders of magnitude greater in lancelets than in other metazoa and it was suggested that continuous activity of transposable elements in lancelets is responsible for this increased rate of protein innovation. Since morphologically Chinese and Florida lancelets are highly conserved, this finding would contradict the observation that high rates of protein innovation are usually associated with major evolutionary innovations. Here we show that the conclusion that the rate of proteome innovation is exceptionally high in lancelets may be unjustified: the differences observed in domain architectures of orthologous proteins of different amphioxus species probably reflect high rates of gene prediction errors rather than true innovation.

  20. High Count Rate Single Photon Counting Detector Array Project

    Data.gov (United States)

    National Aeronautics and Space Administration — An optical communications receiver requires efficient and high-rate photon-counting capability so that the information from every photon, received at the aperture,...

  1. Quantum Communication with a High-Rate Entangled Photon Source

    Science.gov (United States)

    Wilson, Nathaniel C.; Chaffee, Dalton W.; Lekki, John D.; Wilson, Jeffrey D.

    2016-01-01

    A high generation rate photon-pair source using a dual element periodically-poled potassium titanyl phosphate (PP KTP) waveguide is described. The photon-pair source features a high pair generation rate, a compact power-efficient package, and continuous wave (CW) or pulsed operation. Characterization and test results are presented. Details and preliminary results of a laboratory free-space QKD experiment with the B92 protocol are also presented.

  2. High rate resistive plate chamber for LHC detector upgrades

    Energy Technology Data Exchange (ETDEWEB)

    Haddad, Y., E-mail: haddad@llr.in2p3.fr [Laboratoire Leprince-Ringuet (LLR), École Polytechnique, 91120 Palaiseau (France); Laktineh, I.; Grenier, G.; Lumb, N. [IPNL, Villeurbanne 69622 Lyon (France); Cauwenbergh, S. [Ghent University, Ghent (Belgium)

    2013-08-01

    The limitation of the detection rate of standard bakelite resistive plate chambers (RPCs) used as muon detectors in the LHC experiments has prevented the use of such detectors in the high rate regions in both CMS and ATLAS detectors. One alternative to these detectors is RPCs made with low resistivity glass plates (10{sup 10}Ωcm), a beam test at DESY has shown that such detectors can operate at few thousand Hz/cm{sup 2} with high efficiency (>90%)

  3. Development and application of a high-temperature sampling probe for burning chamber conditions of fluidized-bed combustion; Korkean laempoetilan naeytteenottosondin kehittaeminen ja soveltaminen leijukerrospolton tulipesaeolosuhteisiin

    Energy Technology Data Exchange (ETDEWEB)

    Larjava, K.; Paerkkae, M.; Jormanainen, P.; Roine, J.; Paakkinen, K. [VTT Chemistry, Espoo (Finland); Linna, V. [VTT Energy, Jyvaeskylae (Finland)

    1996-12-01

    A sampling probe for the burning chamber conditions of fluidized-bed combustion will be developed in this project. The probe will be suitable for sampling vaporous heavy and alkali metals and other condensing compounds (e.g. chlorides) as well combustion gases and alternatively also flue gas particles at high temperatures. The knowledge gained with the probe will help understanding, developing and modeling combustion processes and will thus aid the manufacturers of the boilers. (author)

  4. Critical Size for the Particle Burn-out of Solid Carbon and/or Boron as the High-Energy Density Fuel

    OpenAIRE

    2013-01-01

    It is intended to demonstrate an existence of the critical size for the particle burn-out, exposed directly to oxidizers at high temperatures under which oxide vaporization can be facilitated, with the solid carbon taken as an example, under recognition that particles considered are too small to support a gas-phase envelop-flame even at elevated temperatures. After describing the temporal variations of the particle temperature and size, use has been made of the asymptotics to derive the gover...

  5. Burns (For Parents)

    Science.gov (United States)

    ... Child What Kids Say About: Handling Stress Anxiety, Fears, and Phobias Community Service: A Family's Guide to Getting ... What's in this article? Common Causes Types of Burns First-Degree Burns Second-Degree Burns ...

  6. [Epidemiological investigation of 615 patients with chemical burns in eastern China].

    Science.gov (United States)

    Gao, Hui; Li, Wei; Zhao, Yuan-dang

    2012-12-01

    total or tangential excision of eschar within one week post injury. Among all the patients, 599 cases were cured with 11 eyes becoming blind in 8 patients, and sixteen patients died with a mortality rate of 2.6%. Patients with chemical burns accounted for a high proportion of the burn patients admitted to our unit in the same period, and they were mainly injured while working. Sufficient irrigation and immediate detoxification are key points in the treatment of chemical burns. Early total or tangential excision of eschar of deep wounds could reduce the possibility of poisoning.

  7. [Hydrofluoric acid burns].

    Science.gov (United States)

    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.

  8. High strain rate loading of polymeric foams and solid plastics

    Science.gov (United States)

    Dick, Richard D.; Chang, Peter C.; Fourney, William L.

    2000-04-01

    The split-Hopkinson pressure bar (SHPB) provided a technique to determine the high strain rate response for low density foams and solid ABS and polypropylene plastics. These materials are used in the interior safety panels of automobiles and crash test dummies. Because the foams have a very low impedance, polycarbonate bars were used to acquire the strain rate data in the 100 to 1600 l/s range. An aluminum SPHB setup was used to obtain the solid plastics data which covered strain rates of 1000 to 4000 l/s. The curves for peak strain rate versus peak stress for the foams over the test range studied indicates only a slight strain rate dependence. Peak strain rate versus peak stress curves for polypropylene shows a strain rate dependence up to about 1500 l/s. At that rate the solid poly propylene indicates no strain rate dependence. The ABS plastics are strain rate dependent up to 3500 l/s and then are independent at larger strain rates.

  9. HIGH HEATING RATES AFFECTS GREATLY THE INACTIVATION RATE OF ESCHERICHIA COLI

    Directory of Open Access Journals (Sweden)

    Juan Pablo Huertas

    2016-08-01

    Full Text Available Heat resistance of microorganisms can be affected by different influencing factors. Although the effect of heating rates has been scarcely explored by the scientific community, recent researches have unraveled its important effect on the thermal resistance of different species of vegetative bacteria. Typically heating rates described in the literature ranged from 1 to 20ºC/min but the impact of much higher heating rates is unclear. The aim of this research was to explore the effect of different heating rates, such as those currently achieved in the heat exchangers used in the food industry, on the heat resistance of Escherichia coli. A pilot plant tubular heat exchanger and a thermoresistometer Mastia were used for this purpose. Results showed that fast heating rates had a deep impact on the thermal resistance of E. coli. Heating rates between 20 and 50ºC/min were achieved in the heat exchanger, which were much slower than those around 20ºC/s achieved in the thermoresistometer. In all cases, these high heating rates led to higher inactivation than expected: in the heat exchanger, for all the experiments performed, when the observed inactivation had reached about seven log cycles, the predictions estimates about 1 log cycle of inactivation; in the thermoresistometer these differences between observed and predicted values were even more than ten times higher, from 4.07 log cycles observed to 0.34 predicted at a flow rate of 70 mL/min and a maximum heating rate of 14.7ºC/s. A quantification of the impact of the heating rates on the level of inactivation achieved was established. These results point out the important effect that the heating rate has on the thermal resistance of E. coli, with high heating rates resulting in an additional sensitization to heat and therefore an effective food safety strategy in terms of food processing.

  10. High Heating Rates Affect Greatly the Inactivation Rate of Escherichia coli

    Science.gov (United States)

    Huertas, Juan-Pablo; Aznar, Arantxa; Esnoz, Arturo; Fernández, Pablo S.; Iguaz, Asunción; Periago, Paula M.; Palop, Alfredo

    2016-01-01

    Heat resistance of microorganisms can be affected by different influencing factors. Although, the effect of heating rates has been scarcely explored by the scientific community, recent researches have unraveled its important effect on the thermal resistance of different species of vegetative bacteria. Typically heating rates described in the literature ranged from 1 to 20°C/min but the impact of much higher heating rates is unclear. The aim of this research was to explore the effect of different heating rates, such as those currently achieved in the heat exchangers used in the food industry, on the heat resistance of Escherichia coli. A pilot plant tubular heat exchanger and a thermoresistometer Mastia were used for this purpose. Results showed that fast heating rates had a deep impact on the thermal resistance of E. coli. Heating rates between 20 and 50°C/min were achieved in the heat exchanger, which were much slower than those around 20°C/s achieved in the thermoresistometer. In all cases, these high heating rates led to higher inactivation than expected: in the heat exchanger, for all the experiments performed, when the observed inactivation had reached about seven log cycles, the predictions estimated about 1 log cycle of inactivation; in the thermoresistometer these differences between observed and predicted values were even more than 10 times higher, from 4.07 log cycles observed to 0.34 predicted at a flow rate of 70 mL/min and a maximum heating rate of 14.7°C/s. A quantification of the impact of the heating rates on the level of inactivation achieved was established. These results point out the important effect that the heating rate has on the thermal resistance of E. coli, with high heating rates resulting in an additional sensitization to heat and therefore an effective food safety strategy in terms of food processing. PMID:27563300

  11. Radio Interface for High Data Rate Wireless Sensor Networks

    CERN Document Server

    Henaut, Julien; Dragomirescu, Daniela; Plana, Robert

    2010-01-01

    This paper gives an overview of radio interfaces devoted for high data rate Wireless Sensor Networks. Four aerospace applications of WSN are presented to underline the importance of achieving high data rate. Then, two modulation schemes by which High Data Rate can be achieved are compared : Multi carrier approaches, represented by the popular Orthogonal Frequency Division Multiplexing (OFDM) and Single carrier methods, represented by Single Carrier Frequency division Equalization and its application for multiple access Single Carrier Frequency division multiple Access (SC-FDMA). SC-FDMA, with a very low Peak Average Power Ratio (PAPR), is as strong alternative to the OFDM scheme for highly power constraint application. The Chosen radio interface will be, finally, tested by a model based design approach based on Simulink and FPGA realization. SC-FDMA, with a very low Peak Average Power Ratio (PAPR), is as strong alternative to the OFDM scheme for highly power constraint application. The Chosen radio interface ...

  12. Stretching Behavior of Red Blood Cells at High Strain Rates

    Science.gov (United States)

    Mancuso, Jordan; Ristenpart, William

    2016-11-01

    Most work on the mechanical behavior of red blood cells (RBCs) has focused on simple shear flows. Relatively little work has examined RBC deformations in the physiologically important extensional flow that occurs at the entrance to a constriction. In particular, previous work suggests that RBCs rapidly stretch out and then retract upon entering the constriction, but to date no model predicts this behavior for the extremely high strain rates typically experienced there. In this work, we use high speed video to perform systematic measurements of the dynamic stretching behavior of RBCs as they enter a microfluidic constriction. We demonstrate that a simple viscoelastic model captures the observed stretching dynamics, up to strain rates as high as 1000 s-1. The results indicate that the effective elastic modulus of the RBC membrane at these strain rates is an order of magnitude larger than moduli measured by micropipette aspiration or other low strain rate techniques.

  13. Effects of non-equilibrium particle distributions in deuterium-tritium burning

    Energy Technology Data Exchange (ETDEWEB)

    Michta, D; Graziani, F; Pruet, J; Luu, T

    2009-08-18

    We investigate the effects of non-equilibrium particle distributions resulting from rapid deuterium-tritium burning in plasmas using a Fokker-Planck code that incorporates small-angle Coulomb scattering, Brehmsstrahlung, Compton scattering, and thermal-nuclear burning. We find that in inertial confinement fusion environments, deviations away from Maxwellian distributions for either deuterium or tritium ions are small and result in 1% changes in the energy production rates. The deuterium and tritium effective temperatures are not equal, but differ by only about 2.5% near the time of peak burn rate. Simulations with high Z (Xe) dopants show that the dopant temperature closely tracks that of the fuel. On the other hand, fusion product ion distributions are highly non-Maxwellian, and careful treatments of energy-exchange between these ions and other particles is important for determining burn rates.

  14. Solidification at the High and Low Rate Extreme

    Energy Technology Data Exchange (ETDEWEB)

    Meco, Halim [Iowa State Univ., Ames, IA (United States)

    2004-12-19

    The microstructures formed upon solidification are strongly influenced by the imposed growth rates on an alloy system. Depending on the characteristics of the solidification process, a wide range of growth rates is accessible. The prevailing solidification mechanisms, and thus the final microstructure of the alloy, are governed by these imposed growth rates. At the high rate extreme, for instance, one can have access to novel microstructures that are unattainable at low growth rates. While the low growth rates can be utilized for the study of the intrinsic growth behavior of a certain phase growing from the melt. Although the length scales associated with certain processes, such as capillarity, and the diffusion of heat and solute, are different at low and high rate extremes, the phenomena that govern the selection of a certain microstructural length scale or a growth mode are the same. Consequently, one can analyze the solidification phenomena at both high and low rates by using the same governing principles. In this study, we examined the microstructural control at both low and high extremes. For the high rate extreme, the formation of crystalline products and factors that control the microstructure during rapid solidification by free-jet melt spinning are examined in Fe-Si-B system. Particular attention was given to the behavior of the melt pool at different quench-wheel speeds. Since the solidification process takes place within the melt-pool that forms on the rotating quench-wheel, we examined the influence of melt-pool dynamics on nucleation and growth of crystalline solidification products and glass formation. High-speed imaging of the melt-pool, analysis of ribbon microstructure, and measurement of ribbon geometry and surface character all indicate upper and lower limits for melt-spinning rates for which nucleation can be avoided, and fully amorphous ribbons can be achieved. Comparison of the relevant time scales reveals that surface-controlled melt

  15. Reactive burn models and ignition & growth concept

    Energy Technology Data Exchange (ETDEWEB)

    Menikoff, Ralph S [Los Alamos National Laboratory; Shaw, Milton S [Los Alamos National Laboratory

    2010-01-01

    Plastic-bonded explosives are heterogeneous materials. Experimentally, shock initiation is sensitive to small amounts of porosity, due to the formation of hot spots (small localized regions of high temperature). This leads to the Ignition and Growth concept, introduced by Lee and Tarver in 1980, as the basis for reactive burn models. A homogeneized burn rate needs to account for three mesoscale physical effects (i) the density of burnt hot spots, which depends on the lead shock strength; (ii) the growth of the burn fronts triggered by hot spots, which depends on the local deflagration speed; (iii) a geometric factor that accounts for the overlap of deflagration wavelets from adjacent hot spots. These effects can be combined and the burn model defined by specifying the reaction progress variable {lambda}(t) as a function of a dimensionless reaction length {tau}{sub hs}(t)/{ell}{sub hs}, rather than by xpecifying an explicit burn rate. The length scale {ell}{sub hs} is the average distance between hot spots, which is proportional to [N{sub hs}(P{sub s})]{sup -1/3}, where N{sub hs} is the number density of hot spots activated by the lead shock. The reaction length {tau}{sub hs}(t) = {line_integral}{sub 0}{sup t} D(P(t'))dt' is the distance the burn front propagates from a single hot spot, where D is the deflagration speed and t is the time since the shock arrival. A key implementation issue is how to determine the lead shock strength in conjunction with a shock capturing scheme. They have developed a robust algorithm for this purpose based on the Hugoniot jump condition for the energy. The algorithm utilizes the time dependence of density, pressure and energy within each cell. The method is independent of the numerical dissipation used for shock capturing. It is local and can be used in one or more space dimensions. The burn model has a small number of parameters which can be calibrated to fit velocity gauge data from shock initiation experiments.

  16. Burn Injuries Resulting from Hot Water Bottle Use: A Retrospective Review of Cases Presenting to a Regional Burns Unit in the United Kingdom

    Directory of Open Access Journals (Sweden)

    Shehab Jabir

    2013-01-01

    Full Text Available Introduction. Hot water bottles are commonly used to relieve pain and for warmth during the colder months of the year. However, they pose a risk of serious burn injuries. The aim of this study is to retrospectively review all burn injuries caused by hot water bottles presenting to our regional burns unit. Methods. Patients with burns injuries resulting from hot water bottle use were identified from our burns database between the periods of January 2004 and March 2013 and their cases notes reviewed retrospectively. Results. Identified cases involved 39 children (aged 17 years or younger and 46 adults (aged 18 years or older. The majority of burns were scald injuries. The mean %TBSA was 3.07% (SD ± 3.40. Seven patients (8.24% required debridement and skin grafting while 3 (3.60% required debridement and application of Biobrane. One patient (1.18% required local flap reconstruction. Spontaneous rupture accounted for 48.20% of injuries while accidental spilling and contact accounted for 33% and 18.80% of injuries, respectively. The mean time to heal was 28.87 days (SD ± 21.60. Conclusions. This study highlights the typical distribution of hot water bottle burns and the high rate of spontaneous rupture of hot water bottles, which have the potential for significant burn injuries.

  17. High deposition rate nanocrystalline silicon with enhanced homogeneity

    NARCIS (Netherlands)

    Verkerk, A.; Rath, J.K.; Schropp, R.E.I.

    2010-01-01

    High rate growth of hydrogenated nanocrystalline silicon (nc-Si:H) brings additional challenges for the homogeneity in the growth direction, since the start-up effects affect a larger portion of the film, and the very high degree of depletion increases the influence of back diffusion from the inacti

  18. Burn treatment in the elderly.

    Science.gov (United States)

    Keck, M; Lumenta, D B; Andel, H; Kamolz, L P; Frey, M

    2009-12-01

    The population of elderly patients is expected to rise continuously over the next decades due to global demographic changes. The elderly seem to be most vulnerable to burns and their management remains undoubtedly a challenge. A clear age margin for elderly patients is not yet defined, but most studies adhere to the inclusion of patients 65 years and above, but the general condition and social situation must be taken into account. The understanding of the physiological basis of aging and its related pathophysiological changes has only marginally influenced treatment and decision making in elderly burn patients. When looking at treatment regimens currently applied in elderly burn patients, the discussion of standards in intensive care as well as surgical strategies is ongoing. However, trends towards a moderate, non-aggressive resuscitation approach and careful inclusion of key parameters like physiological age, pre-burn functional status and premorbid conditions, seem to be useful guidelines for interdisciplinary treatment decisions. Once ordered for surgical treatment, the amount of body surface area operated in one session should be adapted to the general status of the patient. Even if older burn victims have a reported higher mortality rate than younger patients, improved therapeutic options have contributed to a reduced mortality rate even in the elderly over the last decades. As a result of improved outcome, more attention has to be given to a comprehensive rehabilitation program. This review will give an overview of the current literature and will draw attention to specific topics related to this important subpopulation of burn patients.

  19. Erosive burning of solid propellants

    Science.gov (United States)

    King, Merrill K.

    1993-01-01

    Presented here is a review of the experimental and modeling work concerning erosive burning of solid propellants (augmentation of burning rate by flow of product gases across a burning surface). A brief introduction describes the motor design problems caused by this phenomenon, particularly for low port/throat area ratio motors and nozzleless motors. Various experimental techniques for measuring crossflow sensitivity of solid propellant burning rates are described, with the conclusion that accurate simulation of the flow, including upstream flow development, in actual motors is important since the degree of erosive burning depends not only on local mean crossflow velocity and propellant nature, but also upon this upstream development. In the modeling area, a brief review of simplified models and correlating equations is presented, followed by a description of more complex numerical analysis models. Both composite and double-base propellant models are reviewed. A second generation composite model is shown to give good agreement with data obtained in a series of tests in which composite propellant composition and heterogeneity (particle size distribution) were systematically varied. Finally, the use of numerical models for the development of erosive burning correlations is described, and a brief discussion of scaling is presented.

  20. MSFR TRU-burning potential and comparison with an SFR

    Energy Technology Data Exchange (ETDEWEB)

    Fiorina, C.; Cammi, A. [Politecnico di Milano: Via La Masa 34, 20136 Milan (Italy); Franceschini, F. [Westinghouse Electric Company LL: 1000 Westinghouse Dr., Cranberry Township, PA 16066 (United States); Krepel, J. [Paul Scherrer Institut - PSI WEST, 5234 Villigen (Switzerland)

    2013-07-01

    The objective of this work is to evaluate the Molten Salt Fast Reactor (MSFR) potential benefits in terms of transuranics (TRU) burning through a comparative analysis with a sodium-cooled FR. The comparison is based on TRU- and MA-burning rates, as well as on the in-core evolution of radiotoxicity and decay heat. Solubility issues limit the TRU-burning rate to 1/3 that achievable in traditional low-CR FRs (low-Conversion-Ratio Fast Reactors). The softer spectrum also determines notable radiotoxicity and decay heat of the equilibrium actinide inventory. On the other hand, the liquid fuel suggests the possibility of using a Pu-free feed composed only of Th and MA (Minor Actinides), thus maximizing the MA burning rate. This is generally not possible in traditional low-CR FRs due to safety deterioration and decay heat of reprocessed fuel. In addition, the high specific power and the lack of out-of-core cooling times foster a quick transition toward equilibrium, which improves the MSFR capability to burn an initial fissile loading, and makes the MSFR a promising system for a quick (i.e., in a reactor lifetime) transition from the current U-based fuel cycle to a novel closed Th cycle. (authors)

  1. Burned rice straw reduces the availability of clomazone to barnyardgrass.

    Science.gov (United States)

    Xu, Chao; Liu, Weiping; Sheng, G Daniel

    2008-03-25

    Field burning of crop residue is a common post-harvest practice to dispose of these agricultural by-products and for land clearing. Burned crop residues may effectively adsorb pesticides and thus influence their bioavailability in agricultural soils. The adsorption of clomazone by a soil amended with a burned rice straw (BRS) was measured. The availability of clomazone to barnyardgrass in the soil in the absence and presence of BRS was tested. The BRS was 1000-20,000 times more effective than soil in sorbing clomazone. The sorption of clomazone by soil increased with increasing BRS amount in the soil. In a bioassay, the injury of barnyardgrass 9 days after planting decreased with increasing BRS amount in soil indicating the effect of BRS on clomazone availability. Residual analyses showed higher concentrations of clomazone in soils receiving higher rates of the herbicide than in soils with lower application rates suggesting the adsorptive role of BRS. At typical application rate of clomazone (0.3 microg g(-1)), BRS amounts of 0.02 wt.% and higher caused an appreciable reduction to a complete loss in clomazone availability. Calculations suggest that field burning of rice straw may result in sufficiently high amounts (>0.02 wt.%) of BRS, and hence contribute to often experienced loss of pesticide availability in agricultural soils. Our results may be extended to field situations where other crop residues and vegetation are burned. Alternative management of crop residues may improve the bioavailability of pesticides in agricultural soils.

  2. A Survey of Suicide by Burning in Tehran, Iran

    Directory of Open Access Journals (Sweden)

    Fakhredin Taghaddosinejad

    2010-08-01

    Full Text Available To identify the characteristics of completed suicide by burning in Tehran. A retrospective analysis of data obtained from Tehran's Legal Medicine Organization and judiciary system over 5-years (from 2002 to 2006. During the 5 years, 374 decedents (64.2% female and 35.8% male were diagnosed as suicide by self-burning, and the annual incidence rate was 0.9 per 100,000 general population-years. The most at risk group was young females. Sixty-five decedents (17.4% had died at the scene of incidents. The location at the time of attempted suicide in all female victims and 75.4% of male decedents was home. Sixty-one percent of decedents were married and 26.2% of them had no education. Most victims were residents of suburban areas. The annual incidence rate of self-burning suicide in Tehran was found to be lower than other Iran's geographic areas, although it was higher than developed countries. Self-burning was more frequent in females than in males and was noted mainly in young age groups' residents of suburban areas with low level of education. These characteristics suggest that social factors are the main drive leading to an unacceptably high rate of suicide by self-burning among women in Tehran.

  3. High-rate squeezing process of bulk metallic glasses

    Science.gov (United States)

    Fan, Jitang

    2017-03-01

    High-rate squeezing process of bulk metallic glasses from a cylinder into an intact sheet achieved by impact loading is investigated. Such a large deformation is caused by plastic flow, accompanied with geometrical confinement, shear banding/slipping, thermo softening, melting and joining. Temperature rise during the high-rate squeezing process makes a main effect. The inherent mechanisms are illustrated. Like high-pressure torsion (HPT), equal channel angular pressing (ECAP) and surface mechanical attrition treatments (SMAT) for refining grain of metals, High-Rate Squeezing (HRS), as a multiple-functions technique, not only creates a new road of processing metallic glasses and other metallic alloys for developing advanced materials, but also directs a novel technology of processing, grain refining, coating, welding and so on for treating materials.

  4. High power, high efficiency millimeter wavelength traveling wave tubes for high rate communications from deep space

    Science.gov (United States)

    Dayton, James A., Jr.

    1991-01-01

    The high-power transmitters needed for high data rate communications from deep space will require a new class of compact, high efficiency traveling wave tubes (TWT's). Many of the recent TWT developments in the microwave frequency range are generically applicable to mm wave devices, in particular much of the technology of computer aided design, cathodes, and multistage depressed collectors. However, because TWT dimensions scale approximately with wavelength, mm wave devices will be physically much smaller with inherently more stringent fabrication tolerances and sensitivity to thermal dissipation.

  5. Evolution of high tooth replacement rates in sauropod dinosaurs.

    Directory of Open Access Journals (Sweden)

    Michael D D'Emic

    Full Text Available BACKGROUND: Tooth replacement rate can be calculated in extinct animals by counting incremental lines of deposition in tooth dentin. Calculating this rate in several taxa allows for the study of the evolution of tooth replacement rate. Sauropod dinosaurs, the largest terrestrial animals that ever evolved, exhibited a diversity of tooth sizes and shapes, but little is known about their tooth replacement rates. METHODOLOGY/PRINCIPAL FINDINGS: We present tooth replacement rate, formation time, crown volume, total dentition volume, and enamel thickness for two coexisting but distantly related and morphologically disparate sauropod dinosaurs Camarasaurus and Diplodocus. Individual tooth formation time was determined by counting daily incremental lines in dentin. Tooth replacement rate is calculated as the difference between the number of days recorded in successive replacement teeth. Each tooth family in Camarasaurus has a maximum of three replacement teeth, whereas each Diplodocus tooth family has up to five. Tooth formation times are about 1.7 times longer in Camarasaurus than in Diplodocus (315 vs. 185 days. Average tooth replacement rate in Camarasaurus is about one tooth every 62 days versus about one tooth every 35 days in Diplodocus. Despite slower tooth replacement rates in Camarasaurus, the volumetric rate of Camarasaurus tooth replacement is 10 times faster than in Diplodocus because of its substantially greater tooth volumes. A novel method to estimate replacement rate was developed and applied to several other sauropodomorphs that we were not able to thin section. CONCLUSIONS/SIGNIFICANCE: Differences in tooth replacement rate among sauropodomorphs likely reflect disparate feeding strategies and/or food choices, which would have facilitated the coexistence of these gigantic herbivores in one ecosystem. Early neosauropods are characterized by high tooth replacement rates (despite their large tooth size, and derived titanosaurs and

  6. Burns, hypertrophic scar and galactorrhea.

    Science.gov (United States)

    Karimi, Hamid; Nourizad, Samad; Momeni, Mahnoush; Rahbar, Hosein; Momeni, Mazdak; Farhadi, Khosro

    2013-07-01

    An 18-year-old woman was admitted to Motahari Burn Center suffering from 30% burns. Treatment modalities were carried out for the patient and she was discharged after 20 days. Three to four months later she developed hypertrophic scar on her chest and upper limbs. At the same time she developed galactorrhea in both breasts and had a disturbed menstrual cycle four months post-burn. On investigation, we found hyperprolactinemia and no other reasons for the high level of prolactin were detected.She received treatment for both the hypertrophic scar and the severe itching she was experiencing. After seven months, her prolactin level had decreased but had not returned to the normal level. It seems that refractory hypertrophic scar is related to the high level of prolactin in burns patients.

  7. Burns, hypertrophic scar and galactorrhea

    Directory of Open Access Journals (Sweden)

    Hamid Karimi

    2013-07-01

    Full Text Available An 18-year old woman was admitted to Motahari Burn Center suffering from 30% burns. Treatment modalities were carried out for the patient and she was discharged after 20 days. Three to four months later she developed hypertrophic scar on her chest and upper limbs .At the same time she developed galactorrhea in both breasts and had a disturbed menstrual cycle four months post-burn. On investigation, we found hyperprolactinemia and no other reasons for the high level of prolactin were detected. She received treatment for both the hypertrophic scar and the severe itching she was experiencing. After seven months, her prolactin level had decreased but had not returned to the normal level. It seems that refractory hypertrophic scar is related to the high level of prolactin in burns patients.

  8. High Frame Rate Synthetic Aperture 3D Vector Flow Imaging

    DEFF Research Database (Denmark)

    Villagómez Hoyos, Carlos Armando; Holbek, Simon; Stuart, Matthias Bo

    2016-01-01

    3-D blood flow quantification with high spatial and temporal resolution would strongly benefit clinical research on cardiovascular pathologies. Ultrasonic velocity techniques are known for their ability to measure blood flow with high precision at high spatial and temporal resolution. However......, current volumetric ultrasonic flow methods are limited to one velocity component or restricted to a reduced field of view (FOV), e.g. fixed imaging planes, in exchange for higher temporal resolutions. To solve these problems, a previously proposed accurate 2-D high frame rate vector flow imaging (VFI......) technique is extended to estimate the 3-D velocity components inside a volume at high temporal resolutions (

  9. High Strain Rate Behavior of Polymer Matrix Composites Analyzed

    Science.gov (United States)

    Goldberg, Robert K.; Roberts, Gary D.

    2001-01-01

    Procedures for modeling the high-speed impact of composite materials are needed for designing reliable composite engine cases that are lighter than the metal cases in current use. The types of polymer matrix composites that are likely to be used in such an application have a deformation response that is nonlinear and that varies with strain rate. To characterize and validate material models that could be used in the design of impactresistant engine cases, researchers must obtain material data over a wide variety of strain rates. An experimental program has been carried out through a university grant with the Ohio State University to obtain deformation data for a representative polymer matrix composite for strain rates ranging from quasi-static to high rates of several hundred per second. This information has been used to characterize and validate a constitutive model that was developed at the NASA Glenn Research Center.

  10. Experimental Research on Temperature Sensitivity Coefficient of Burning Rate for RDX-CMDB Propellant%RDX-CMDB 推进剂燃速温度敏感系数的实验研究

    Institute of Scientific and Technical Information of China (English)

    裴庆; 赵凤起; 郝海霞; 徐司雨; 张衡

    2016-01-01

    为了揭示RDX‐CMDB推进剂中各常见组分对其燃速温度敏感系数的影响规律,制备了一系列含RDX、铝粉及燃烧催化剂的CMDB推进剂样品。采用氮气靶线法测得其在2~14MPa下的燃速温度敏感系数(σp)。讨论了RDX含量、铝粉、燃烧催化剂对RDX‐CMDB推进剂燃速温度敏感系数的影响。结果表明,提高工作压强、增加RDX含量、添加燃烧催化剂均有助于降低RDX‐CMDB推进剂在一定初始条件下的燃速温度敏感系数。配方中引入铝粉后可降低中低压下RDX‐CMDB推进剂的燃速温度敏感系数,且燃速温度敏感系数几乎不随压强变化而变化。选用含邻苯二甲酸铅和没食子酸铋锆作燃烧催化剂,均可在2~10MPa下降低RDX‐CMDB推进剂的燃速压强指数,同时降低燃速温度敏感系数。%In order to reveal the effects of the commonly used component on temperature sensitivity coefficient of burning rate for RDX‐CMDB propellant ,a series of propellant samples containing RDX ,aluminium powder and combustion catalyst were prepared .Their temperature sensitivity coefficients of burning rate σP were determined at the pressure of 2MPa to 14MPa by using nitrogen strand burner method .The influences of RDX content ,aluminium powder and combustion cata‐lysts on the temperature sensitivity coefficient of burning rate were discussed .The results show that the increase of working pressure and RDX content and the addition of combustion catalyst are healpful to reduce the temperature sensitivity coeffi‐cient of burning rate of RDX‐CMDB propellant under certain initial conditions .After introducing aluminium powder into the formulation ,the temperature sensitivity coefficient of burning rate of RDX‐CMDB propellant at middle and low pressures can be reduced and is almost not changed with the pressure .Using lead phthalate and bismuth/zirconium gallate as combus‐tion catalyst may reduce pressure exponent of

  11. Study of High Strain Rate Response of Composites

    Science.gov (United States)

    Gilat, Amos

    2003-01-01

    The objective of the research was to continue the experimental study of the effect of strain rate on mechanical response (deformation and failure) of epoxy resins and carbon fibers/epoxy matrix composites, and to initiate a study of the effects of temperature by developing an elevated temperature test. The experimental data provide the information needed for NASA scientists for the development of a nonlinear, rate dependent deformation and strength models for composites that can subsequently be used in design. This year effort was directed into testing the epoxy resin. Three types of epoxy resins were tested in tension and shear at various strain rates that ranges from 5 x 10(exp -5), to 1000 per second. Pilot shear experiments were done at high strain rate and an elevated temperature of 80 C. The results show that all, the strain rate, the mode of loading, and temperature significantly affect the response of epoxy.

  12. STIR: Tailored Interfaces for High Strength Composites Across Strain Rates

    Science.gov (United States)

    2013-09-02

    was requested during our kickoff meeting at ARL APG. High performance fabrics including Kevlar, Twaron, Zylon , and Dyneema are used in developing...Kevlar, and Zylon for various pullout rates. Force– displacement data was recorded, and both warp and fill yarns were pulled from the fabric. Their...results presented that the effect of pullout rate is negligible for Kevlar, whereas the effect is bigger on Spectra, and significant for Zylon

  13. High rate tests of the LHCb RICH Upgrade system

    CERN Multimedia

    Blago, Michele Piero

    2016-01-01

    One of the biggest challenges for the upgrade of the LHCb RICH detectors from 2020 is to readout the photon detectors at the full 40 MHz rate of the LHC proton-proton collisions. A test facility has been setup at CERN with the purpose to investigate the behaviour of the Multi Anode PMTs, which have been proposed for the upgrade, and their readout electronics at high trigger rates. The MaPMTs are illuminated with a monochromatic laser that can be triggered independently of the readout electronics. A first series of tests, including threshold scans, is performed at low trigger rates (20 kHz) for both the readout and the laser with the purpose to characterise the behaviour of the system under test. Then the trigger rate is increased in two separate steps. First the MaPMTs are exposed to high illumination by triggering the pulsed laser at a high (20 MHz) repetition rate while the DAQ is readout at the same low rate as before. In this way the performance of the MaPMTs and the attached electronics can be evaluated ...

  14. An overview on the establishment of the system of burn prevention and treatment in China by comparing with that of foreign countries%从中外比较看我国烧伤防治体系建设

    Institute of Scientific and Technical Information of China (English)

    谢卫国

    2013-01-01

    The number of burn patients in China is still huge because of the demographic and socio-economical reasons.Distinguished achievements have been made in Chinese burn surgery during decades of development,with a generally acknowledged high survival rate of burn victims.However,there are still many problems,including an emphasis on the treatment rather than on prevention,poor pre-hospital care system,unbalanced development of burn centers,shortage of burn rehabilitation and psycho-social support,shortage of financial support,and underdevelopment of social charity for burn patients.0nly if the efforts of the burn centers,government,and the whole society join together can the problems be solved and a good system of burn prevention,clinical care,and rehabilitation be established and perfected.The deficiencies in the development of the system in China and the possible solutions are reviewed and discussed in this paper.

  15. Nanoengineering Titania for High Rate Lithium Storage: A Review

    Institute of Scientific and Technical Information of China (English)

    Chunhai Jiang; Jinsong Zhang

    2013-01-01

    Nanostructured titania have been intensively investigated as anode materials of Li-ion batteries for their excellent high rate performance.The size effects of TiO2 polymorphs (mainly rutile,anatase and TiO2-B) on their electrochemical performance and the latest efforts in nanoengineering titania anodes through enhancing their ionic or electronic transportation or both are reviewed in this work.We suppose that micron-or submicronsized porous structures assembled by TiO2 nanoparticles,nanowires/nanotubes or nanosheets with a high percentage of exposing high reactive facets together with a conductive percolating network are ideal anodes not only for high rate lithium storage but also for high packing densities of the active materials.

  16. Semi-solid electrodes having high rate capability

    Energy Technology Data Exchange (ETDEWEB)

    Chiang, Yet-Ming; Duduta, Mihai; Holman, Richard; Limthongkul, Pimpa; Tan, Taison

    2016-07-05

    Embodiments described herein relate generally to electrochemical cells having high rate capability, and more particularly to devices, systems and methods of producing high capacity and high rate capability batteries having relatively thick semi-solid electrodes. In some embodiments, an electrochemical cell includes an anode, a semi-solid cathode that includes a suspension of an active material and a conductive material in a liquid electrolyte, and an ion permeable membrane disposed between the anode and the cathode. The semi-solid cathode has a thickness in the range of about 250 .mu.m-2,500 .mu.m, and the electrochemical cell has an area specific capacity of at least 5 mAh/cm.sup.2 at a C-rate of C/2.

  17. Semi-solid electrodes having high rate capability

    Energy Technology Data Exchange (ETDEWEB)

    Chiang, Yet-Ming; Duduta, Mihai; Holman, Richard; Limthongkul, Pimpa; Tan, Taison

    2015-11-10

    Embodiments described herein relate generally to electrochemical cells having high rate capability, and more particularly to devices, systems and methods of producing high capacity and high rate capability batteries having relatively thick semi-solid electrodes. In some embodiments, an electrochemical cell includes an anode, a semi-solid cathode that includes a suspension of an active material and a conductive material in a liquid electrolyte, and an ion permeable membrane disposed between the anode and the cathode. The semi-solid cathode has a thickness in the range of about 250 .mu.m-2,500 .mu.m, and the electrochemical cell has an area specific capacity of at least 5 mAh/cm.sup.2 at a C-rate of C/2.

  18. High strain rate compression testing of glass fibre reinforced polypropylene

    Directory of Open Access Journals (Sweden)

    Cloete T.J.

    2012-08-01

    Full Text Available This paper details an investigation of the high strain rate compression testing of GFPP with the Split Hopkinson Pressure Bar (SHPB in the through-thickness and in-plane directions. GFPP posed challenges to SHPB testing as it fails at relatively high stresses, while having relatively low moduli and hence mechanical impedance. The modifications to specimen geometry and incident pulse shaping in order to gather valid test results, where specimen equilibrium was achieved for SHPB tests on GFPP are presented. In addition to conventional SHPB tests to failure, SHPB experiments were designed to achieve specimen equilibration at small strains, which permitted the capture of high strain rate elastic modulus data. The strain rate dependency of GFPP’s failure strengths in the in-plane and through-thickness direction is modelled using a logarithmic law.

  19. High-Strain Rate Mechanical Response of Cured Epoxy Networks

    Science.gov (United States)

    Sirk, Timothy; Khare, Ketan; Karim, Mir; Lenhart, Joseph; Khare, Rajesh; Andzelm, Jan

    2013-03-01

    Chemically cross-linked polymer networks are increasingly common in high performance composites, adhesives and other applications involving high-impact loading conditions or ballistic collisions. The mechanical behavior of epoxy and other polymer networks exhibit a strong dependence on strain rate near the glass transition temperature (Tg); however, the elastic modulus at strain rates greater than 105 1/s is difficult to capture with experimental techniques. We present computational results of Di-Glycidyl Ether of Bisphenol A (DGEBA) and Jeffamine diamines (D230) from molecular dynamics simulation, which is intrinsically well-suited to model material deformation at high strain rates. Our results show that the experimental Tg can be reproduced from molecular dynamics, and the Williams-Landel-Ferry equation is useful in rationalizing the shift of Tg due to fast annealing and high strain rates. Temperature sweeps of elastic modulus show the glass-rubber transition to occur over a significantly wider temperature range compared with experimental measurements at low strain rates.

  20. Epidemiology of pediatric burns requiring hospitalization in China: a literature review of retrospective studies.

    Science.gov (United States)

    Kai-Yang, Lv; Zhao-Fan, Xia; Luo-Man, Zhang; Yi-Tao, Jia; Tao, Tan; Wei, Wei; Bing, Ma; Jie, Xiong; Yu, Wang; Yu, Sun

    2008-07-01

    This review was an effort to systematically examine the nationwide data available on pediatric burns requiring hospitalization to reveal burn epidemiology and guide future education and prevention. The China Biomedical Disk Database, Chongqing VIP Database, and China Journal Full-Text Database were searched for articles reporting data on children and their burns from January 2000 through December 2005. Studies were included that systematically investigated the epidemiology of pediatric burns requiring hospitalization in China. Twenty-eight articles met the inclusion criteria, all of which were retrospective analyses. For each study included, 2 investigators independently abstracted the data related to the population description by using a standard form and included the percentage of patients with burn injury who were burn; anatomical sites of burn; severity of burn; and mortality and cause of death. These data were extracted, and a retrospective statistical description was performed with SPSS11.0 (SPSS Inc, Chicago, IL). Of the pediatric patients studied, the proportion of children with burn injury ranged from 22.50% to 54.66%, and the male/female ratio ranged from 1.25:1 to 4.42:1. The ratio of children aged 3 years was 0.19:1 to 4.18:1. The rural/urban ratio was 1.60:1 to 12.94:1. The ratio of those who were burned indoors versus outdoors was 1.62 to 17.00, and there were no effective hints on the distribution of seasons and anatomical sites of burn that could be found. The peak hours of pediatric burn were between 17:00 and 20:00. Most articles reported the sequence of reasons as hot liquid > flame > electricity > chemical, and scalding was, by far, the most predominant reason for burn. The majority of the studies reported the highest proportion involved in moderate burn, and the lowest proportion was for critical burn. The mortality rate ranged from 0.49% to 9.08%, and infection, shock, and multiple organ dysfunction syndrome were the most common causes of

  1. High removal rate laser-based coating removal system

    Science.gov (United States)

    Matthews, Dennis L.; Celliers, Peter M.; Hackel, Lloyd; Da Silva, Luiz B.; Dane, C. Brent; Mrowka, Stanley

    1999-11-16

    A compact laser system that removes surface coatings (such as paint, dirt, etc.) at a removal rate as high as 1000 ft.sup.2 /hr or more without damaging the surface. A high repetition rate laser with multiple amplification passes propagating through at least one optical amplifier is used, along with a delivery system consisting of a telescoping and articulating tube which also contains an evacuation system for simultaneously sweeping up the debris produced in the process. The amplified beam can be converted to an output beam by passively switching the polarization of at least one amplified beam. The system also has a personal safety system which protects against accidental exposures.

  2. Strategies for adapting to high rates of employee turnover.

    Science.gov (United States)

    Mowday, R T

    1984-01-01

    For many organizations facing high rates of employee turnover, strategies for increasing employee retention may not be practical because employees leave for reasons beyond the control of management or the costs of reducing turnover exceed the benefits to be derived. In this situation managers need to consider strategies that can minimize or buffer the organization from the negative consequences that often follow from turnover. Strategies organizations can use to adapt to uncontrollably high employee turnover rates are presented in this article. In addition, suggestions are made for how managers should make choices among the alternative strategies.

  3. The application of FORMOSAT-2 high-temporal- and high-spatial resolution imagery for monitoring open straw burning and carbon emission detection

    Directory of Open Access Journals (Sweden)

    C.-C. Liu

    2013-03-01

    Full Text Available Rice is produced in more than 95 countries worldwide and is a staple food for over half of the world's population. Rice is also a major food crop of Taiwan. There are numerous rice crops planted on the western plains of Taiwan, and, after the harvest season, the left-over straw is often burned on-site. The air pollutants from the burning emissions include CO2, CO, CH4 and other suspended particles, most of these being the greenhouse gases which cause global climate change. In this study FORMOSAT-2 satellite images and ground-truth data from 2008 and 2009 are used to conduct supervised classification and calculate the extent of the straw burning areas. It was found that 10% of the paddies in the study area were burned after harvest during this 2-yr period. On this pro rata basis, we calculated the overall carbon emissions from the burning of the straw. The findings showed that these few farmers produced up to 34 000 tons of carbon emissions in 2008, and 40 000 tons in 2009. The study results indicate that remotely sensed images can be used to efficiently evaluate the important characteristics for carbon emission detection. It also provides quantitative results that are relevant to tracking sources of transport pollution, postharvest burning, and Asian dust in Taiwan.

  4. The application of FORMOSAT-2 high-temporal- and high-spatial resolution imagery for monitoring open straw burning and carbon emission detection

    Science.gov (United States)

    Liu, C.-C.; Tseng, P.-Y.; Chen, C.-Y.

    2013-03-01

    Rice is produced in more than 95 countries worldwide and is a staple food for over half of the world's population. Rice is also a major food crop of Taiwan. There are numerous rice crops planted on the western plains of Taiwan, and, after the harvest season, the left-over straw is often burned on-site. The air pollutants from the burning emissions include CO2, CO, CH4 and other suspended particles, most of these being the greenhouse gases which cause global climate change. In this study FORMOSAT-2 satellite images and ground-truth data from 2008 and 2009 are used to conduct supervised classification and calculate the extent of the straw burning areas. It was found that 10% of the paddies in the study area were burned after harvest during this 2-yr period. On this pro rata basis, we calculated the overall carbon emissions from the burning of the straw. The findings showed that these few farmers produced up to 34 000 tons of carbon emissions in 2008, and 40 000 tons in 2009. The study results indicate that remotely sensed images can be used to efficiently evaluate the important characteristics for carbon emission detection. It also provides quantitative results that are relevant to tracking sources of transport pollution, postharvest burning, and Asian dust in Taiwan.

  5. Particulate hydroxy-PAH emissions from a residential wood log stove using different fuels and burning conditions

    Science.gov (United States)

    Avagyan, Rozanna; Nyström, Robin; Lindgren, Robert; Boman, Christoffer; Westerholm, Roger

    2016-09-01

    Hydroxylated polycyclic aromatic hydrocarbons are oxidation products of polycyclic aromatic hydrocarbons, but have not been studied as extensively as polycyclic aromatic hydrocarbons. Several studies have however shown that hydroxylated polycyclic aromatic hydrocarbons have toxic and carcinogenic properties. They have been detected in air samples in semi urban areas and combustion is assumed to be the primary source of those compounds. To better understand the formation and occurrence of particulate hydroxylated polycyclic aromatic hydrocarbons from residential wood log stove combustion, 9 hydroxylated polycyclic aromatic hydrocarbons and 2 hydroxy biphenyls were quantified in particles generated from four different types of wood logs (birch, spruce, pine, aspen) and two different combustion conditions (nominal and high burn rate). A previously developed method utilizing liquid chromatography - photo ionization tandem mass spectrometry and pressurized liquid extraction was used. Polycyclic aromatic hydrocarbons were analyzed along with hydroxylated polycyclic aromatic hydrocarbons. The hydroxylated polycyclic aromatic hydrocarbon emissions varied significantly across different wood types and burning conditions; the highest emissions for nominal burn rate were from spruce and for high burn rate from pine burning. Emissions from nominal burn rate corresponded on average to 15% of the emissions from high burn rate, with average emissions of 218 μg/MJfuel and 32.5 μg/MJfuel for high burn rate and nominal burn rate, respectively. Emissions of the measured hydroxylated polycyclic aromatic hydrocarbons corresponded on average to 28% of polycyclic aromatic hydrocarbons emissions. This study shows that wood combustion is a large emission source of hydroxylated polycyclic aromatic hydrocarbons and that not only combustion conditions, but also wood type influences the emissions of hydroxylated polycyclic aromatic hydrocarbons and polycyclic aromatic hydrocarbons. There are

  6. Mechanism of Modifying Ballistic Properties of Propellant Formulations by Fast-Burning Inclusions

    Directory of Open Access Journals (Sweden)

    A. E. Fogelzang

    1998-10-01

    Full Text Available The combustion characteristics of binary compositions of fast-burning energetic materials (FBEM with main composite propellant components like ammonium perchlorate (AP and polymeric binders have been studied in a constant pressure bomb, and combustion mechanism has been proposed. Combustion behaviour of composite propellants containing granulated FBEM of different particle sizes has been investigated. FBEM additives as high as 40 per cent of fine particle size to a composite propellant have not been shown to influence markedly the burning rate, whereas incorporation of FBEM grains of 500 micrometer particle size allows not only a considerable increase in the burning rate but also modifies the burning rate-pressure dependence. A mechanism of combustion of propellant compositions containing FBEM grains has been evolved that allows criteria for FBEM performance and combustion stability.

  7. High frame rate CCD camera with fast optical shutter

    Energy Technology Data Exchange (ETDEWEB)

    Yates, G.J.; McDonald, T.E. Jr. [Los Alamos National Lab., NM (United States); Turko, B.T. [Lawrence Berkeley National Lab., CA (United States)

    1998-09-01

    A high frame rate CCD camera coupled with a fast optical shutter has been designed for high repetition rate imaging applications. The design uses state-of-the-art microchannel plate image intensifier (MCPII) technology fostered/developed by Los Alamos National Laboratory to support nuclear, military, and medical research requiring high-speed imagery. Key design features include asynchronous resetting of the camera to acquire random transient images, patented real-time analog signal processing with 10-bit digitization at 40--75 MHz pixel rates, synchronized shutter exposures as short as 200pS, sustained continuous readout of 512 x 512 pixels per frame at 1--5Hz rates via parallel multiport (16-port CCD) data transfer. Salient characterization/performance test data for the prototype camera are presented, temporally and spatially resolved images obtained from range-gated LADAR field testing are included, an alternative system configuration using several cameras sequenced to deliver discrete numbers of consecutive frames at effective burst rates up to 5GHz (accomplished by time-phasing of consecutive MCPII shutter gates without overlap) is discussed. Potential applications including dynamic radiography and optical correlation will be presented.

  8. Mechanism of Burn Resistance of Alloy Ti40

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The Ti fire found in high performance engines promotes the development of burn resistant Ti alloys. The burn resistant mechanism of Ti40 alloy is investigated. Ti40 alloy reveals good burn resistance. Its interfacial products between burning products and the matrix are tenacious,which retard the diffusion of oxygen into the matrix. Two burn resistant mechanisms, that is, fast scatter dispersion of heat and suppression of oxygen diffusion, are proposed.

  9. User microprogrammable processors for high data rate telemetry preprocessing

    Science.gov (United States)

    Pugsley, J. H.; Ogrady, E. P.

    1973-01-01

    The use of microprogrammable processors for the preprocessing of high data rate satellite telemetry is investigated. The following topics are discussed along with supporting studies: (1) evaluation of commercial microprogrammable minicomputers for telemetry preprocessing tasks; (2) microinstruction sets for telemetry preprocessing; and (3) the use of multiple minicomputers to achieve high data processing. The simulation of small microprogrammed processors is discussed along with examples of microprogrammed processors.

  10. Pedalling rate affects endurance performance during high-intensity cycling

    DEFF Research Database (Denmark)

    Nielsen, Jens Steen; Hansen, Ernst Albin; Sjøgaard, Gisela

    2004-01-01

    , such as muscle fibre type composition and power reserve, relate to endurance time. Twenty males underwent testing to determine their maximal oxygen uptake (VO(2max)), power output corresponding to 90% of VO(2max) at 80 rpm (W90), FCPR at W90, percentage of slow twitch muscle fibres (% MHC I), maximal leg power...... time was negatively related to VO(2max), W90 and % MHC I, while positively related to power reserve. In conclusion, at group level, endurance time was longer at FCPR and at a pedalling rate 25% lower compared to a pedalling rate 25% higher than FCPR. Further, inter-individual physiological variables......The purpose of this study into high-intensity cycling was to: (1) test the hypothesis that endurance time is longest at a freely chosen pedalling rate (FCPR), compared to pedalling rates 25% lower (FCPR-25) and higher (FCPR+25) than FCPR, and (2) investigate how physiological variables...

  11. Evaluation of dissolution rate on high plutonium content MOX fuel

    Energy Technology Data Exchange (ETDEWEB)

    Sugaya, Shinichi; Kurita, Ichiro; Endo, Hideo; Higuchi, Hidetoshi; Kihara, Yoshiyuki [Japan Nuclear Cycle Development Inst., Tokai Works, Tokai, Ibaraki (Japan); Ogasawara, Masahiro; Shinada, Masanori; Kowata, Masato [Inspection Development Company Ltd., Tokai, Ibaraki (Japan)

    2002-06-01

    The dissolution rate of high Pu content MOX fuel into nitric acid was measured as a function of Pu content. MOX fuel samples, pressed and sintered, were dissolved in 7 M of boiling nitric acid, and the dissolution rate was measured by analyzing the Pu and U concentration in the solution. The dissolution rate of MOX fuel tended to decrease with the increase in the Pu content and was reduced after 6 hours of dissolution. These results agreed well with previous ones, but the dissolution rate was 3-6 times faster than those. It is estimated that the cause of this difference was due to underestimation of the surface area of MOX fuel powder and the difference of the MOX O/M ratio. (author)

  12. Methanol conversion in high-rate anaerobic reactors

    NARCIS (Netherlands)

    Weijma, J.; Stams, A.J.M.

    2001-01-01

    An overview on methanol conversion in high-rate anaerobic reactors is presented, with the focus on technological as well as microbiological aspects. The simple C1-compound methanol can be degraded anaerobically in a complex way, in which methanogens, sulfate reducing bacteria and homoacetogens

  13. READOUT ELECTRONICS FOR A HIGH-RATE CSC DETECTOR

    Energy Technology Data Exchange (ETDEWEB)

    OCONNOR,P.; GRATCHEV,V.; KANDASAMY,A.; POLYCHRONAKOS,V.; TCHERNIATINE,V.; PARSONS,J.; SIPPACH,W.

    1999-09-25

    A readout system for a high-rate muon Cathode Strip Chamber (CSC) is described. The system, planned for use in the forward region of the ATLAS muon spectrometer, uses two custom CMOS integrated circuits to achieve good position resolution at a flux of up to 2,500 tracks/cm{sup 2}/s.

  14. Childhood Onset Schizophrenia: High Rate of Visual Hallucinations

    Science.gov (United States)

    David, Christopher N.; Greenstein, Deanna; Clasen, Liv; Gochman, Pete; Miller, Rachel; Tossell, Julia W.; Mattai, Anand A.; Gogtay, Nitin; Rapoport, Judith L.

    2011-01-01

    Objective: To document high rates and clinical correlates of nonauditory hallucinations in childhood onset schizophrenia (COS). Method: Within a sample of 117 pediatric patients (mean age 13.6 years), diagnosed with COS, the presence of auditory, visual, somatic/tactile, and olfactory hallucinations was examined using the Scale for the Assessment…

  15. High Reported Spontaneous Stuttering Recovery Rates: Fact or Fiction?

    Science.gov (United States)

    Ramig, Peter R.

    1993-01-01

    Contact after 6 to 8 years with families of 21 children who were diagnosed as stuttering but did not receive fluency intervention services found that almost all subjects still had a stuttering problem. Results dispute the high spontaneous recovery rates reported in the literature and support the value of early intervention. (Author/DB)

  16. High deposition rate nanocrystalline silicon with enhanced homogeneity

    Energy Technology Data Exchange (ETDEWEB)

    Verkerk, Arjan; Rath, Jatindra K.; Schropp, Ruud [Section Nanophotonics-Physics of Devices, Debye Institute for Nanomaterials Science, Faculty of Science, Utrecht University, P.O. Box 80000, 3508 TA Utrecht (Netherlands)

    2010-03-15

    High rate growth of hydrogenated nanocrystalline silicon (nc-Si:H) brings additional challenges for the homogeneity in the growth direction, since the start-up effects affect a larger portion of the film, and the very high degree of depletion increases the influence of back diffusion from the inactive region into the plasma zone. It was calculated that back diffusion plays a role in the regime for high deposition rate (4.5 nm/s) via the residence time for particles in the plasma and the corresponding diffusion length for silane from outside the plasma. The stabilization time for back diffusion was derived and found to be on the order of tens of seconds. Experiment showed that the incubation layer for nc-Si:H is very thick in films deposited at a high rate compared to films deposited in a regime of lower deposition rate. The use of a hydrogen plasma start greatly reduced this incubation layer. Further control of the crystalline fraction could be achieved via slight reduction of the degree of depletion via the silane flow. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  17. Advances in high rate anaerobic treatment: staging of reactor systems.

    NARCIS (Netherlands)

    Lier, van J.B.; Zee, van der F.P.; Tan, N.C.G.; Rebac, S.; Kleerebezem, R.

    2001-01-01

    Anaerobic wastewater treatment (AnWT) is considered as the most cost-effective solution for organically polluted industrial waste streams. Particularly the development of high-rate systems, in which hydraulic retention times are uncoupled from solids retention times, has led to a world-wide acceptan

  18. Adapting high-rate anaerobic treatment to Middle East conditions

    NARCIS (Netherlands)

    Mahmoud, N.A.; Zeeman, G.; Lier, van J.B.

    2008-01-01

    High-rate anaerobic technologies offer cost-effective solutions for sewage treatment in the Middle East and Palestine in particular. The sewage characteristics in Palestine are quite different from the values elsewhere and show solids contents of more than 1000 mg chemical oxygen demand (COD)ss/L

  19. Binary interactions with high accretion rates onto main sequence stars

    Science.gov (United States)

    Shiber, Sagiv; Schreier, Ron; Soker, Noam

    2016-07-01

    Energetic outflows from main sequence stars accreting mass at very high rates might account for the powering of some eruptive objects, such as merging main sequence stars, major eruptions of luminous blue variables, e.g., the Great Eruption of Eta Carinae, and other intermediate luminosity optical transients (ILOTs; red novae; red transients). These powerful outflows could potentially also supply the extra energy required in the common envelope process and in the grazing envelope evolution of binary systems. We propose that a massive outflow/jets mediated by magnetic fields might remove energy and angular momentum from the accretion disk to allow such high accretion rate flows. By examining the possible activity of the magnetic fields of accretion disks, we conclude that indeed main sequence stars might accrete mass at very high rates, up to ≈ 10-2 M ⊙ yr-1 for solar type stars, and up to ≈ 1 M ⊙ yr-1 for very massive stars. We speculate that magnetic fields amplified in such extreme conditions might lead to the formation of massive bipolar outflows that can remove most of the disk's energy and angular momentum. It is this energy and angular momentum removal that allows the very high mass accretion rate onto main sequence stars.

  20. Understanding High School Graduation Rates in the District of Columbia

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  1. Understanding High School Graduation Rates in New Mexico

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  2. Understanding High School Graduation Rates in Rhode Island

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  3. Understanding High School Graduation Rates in South Dakota

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  4. Understanding High School Graduation Rates in West Virginia

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  5. Understanding High School Graduation Rates in North Carolina

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  6. Understanding High School Graduation Rates in South Carolina

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  7. Understanding High School Graduation Rates in North Dakota

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  8. Understanding High School Graduation Rates in New York

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  9. Understanding High School Graduation Rates in the United States

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  10. Understanding High School Graduation Rates in New Hampshire

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  11. Understanding High School Graduation Rates in New Jersey

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    Graduation rates are a fundamental indicator of whether or not the nation's public school system is doing what it is intended to do: enroll, engage, and educate youth to be productive members of society. Since almost 90 percent of the fastest-growing and highest-paying jobs require some postsecondary education, having a high school diploma and the…

  12. Acute burn during pregnancy: A retrospective study

    Directory of Open Access Journals (Sweden)

    Ezzatollah Rezaei

    2016-01-01

    Full Text Available Background & aim: The incidence of acute burn injuries in pregnant women is very low. Burn injuries during pregnancy are often associated with a high rate of fetal and maternal mortality and morbidity. In this study, we aimed to review the cases of acute burn during pregnancy and evaluate the outcome of these patients in Mashhad, Iran. Methods:This retrospective study was performed using the medical records of 48 pregnant women with thermal injuries over a 13-year period. Results: The results showed that 8 (16.7%, 27 (56.3%, and 13 (27.1% patients were in the first, second, and third trimesters of pregnancy. Moreover, 14 mothers (29.2% died, 24 (50.0% were discharged without any fetal problems, eight (16.7% had fetal death, 13 (27.1% had abortion, two (4.2% had normal vaginal delivery, and one (2.1% underwent normal caesarean section. Conclusion: The rate ofmaternal survival in the first and second trimesters was higher than the third one. In the third trimester, pregnancy termination is indicated only after fetal maturation.

  13. Selective digestive decontamination (SDD) as a tool in the management of bacterial translocation following major burns.

    Science.gov (United States)

    Aboelatta, Y A; Abd-Elsalam, A M; Omar, A H; Abdelaal, M M; Farid, A M

    2013-12-31

    Bacterial translocation after major burns plays an important role in burn sepsis and can be reduced with SDD. 30 patients with burns of 25-50% TBSA were divided into 2 groups. Group I received SDD regimen in the form of amikacin, miconazole, and colistin sulphate. Group II served as a control group. SDD treatment resulted in significant control of infectious episodes and multi-organ dysfunction syndrome (MODS). It also resulted in a reduction of mortality, although this was not statistically significant. Despite the statistical insignificance of the improved mortality rate, SDD treatment seems to be a useful tool in treating this group of highly critical patients.

  14. Mechanisms of high heart rate variability: a fresh look

    Directory of Open Access Journals (Sweden)

    Vladimir A. Lukyanchenko

    2016-05-01

    Full Text Available Consideration is being given herein to some mechanisms of high heart rate variability (high HRV, which cannot be attributed to sports exercise loading. The mechanism responsible for high HRV is explained as that resulted from the continuous performance (opening and closure of arteriovenous anastomoses in different organs and systems in a human organism. An assessment of this phenomenon is given herein from the point of view of a practicing physician who treats regularly patients with already established clinical diagnoses and those without an established nosological profile according to International Statistical Classification of Diseases and Related Health Problems 10th Revision.

  15. OFDM-based Low-voltage Powerline High Rate Communication

    Institute of Scientific and Technical Information of China (English)

    ZHANG You-bing(张有兵); CHENG Shi-jie(程时杰); Joseph Nguimbis; XIONG Lan(熊兰)

    2004-01-01

    Based on the experimental results, a simplified model for low-voltage powerline used as a high frequency communication channel is presented. With this model, the Orthogonal Frequency Division Multiplexing (OFDM) based high rate digital communication over low-voltage powerline is analyzed and simulated. The capability of thc signal transmission system in overcoming multi-path interference and selection of the system parameters are discussed. And time-domain simulation is carried out to investigate the transmission capability of the OFDM cammunication system for different mapping schemes and transmission power levels. Simulation results show that it is possible to realize high rate digital communication over iow-voltage powerliue using OFDM when the transmitted power is large enough.

  16. High strain rate behavior of pure metals at elevated temperature

    Science.gov (United States)

    Testa, Gabriel; Bonora, Nicola; Ruggiero, Andrew; Iannitti, Gianluca; Domenico, Gentile

    2013-06-01

    In many applications and technology processes, such as stamping, forging, hot working etc., metals and alloys are subjected to elevated temperature and high strain rate deformation process. Characterization tests, such as quasistatic and dynamic tension or compression test, and validation tests, such as Taylor impact and DTE - dynamic tensile extrusion -, provide the experimental base of data for constitutive model validation and material parameters identification. Testing material at high strain rate and temperature requires dedicated equipment. In this work, both tensile Hopkinson bar and light gas gun where modified in order to allow material testing under sample controlled temperature conditions. Dynamic tension tests and Taylor impact tests, at different temperatures, on high purity copper (99.98%), tungsten (99.95%) and 316L stainless steel were performed. The accuracy of several constitutive models (Johnson and Cook, Zerilli-Armstrong, etc.) in predicting the observed material response was verified by means of extensive finite element analysis (FEA).

  17. High abundances of water-soluble dicarboxylic acids, ketocarboxylic acids and α-dicarbonyls in the mountaintop aerosols over the North China Plain during wheat burning season

    Directory of Open Access Journals (Sweden)

    K. Kawamura

    2013-08-01

    Full Text Available Aerosol (TSP samples were collected at the summit of Mount Tai (elevation: 1534 m a.s.l., 36.25° N, 117.10° E located in the North China Plain using a high-volume air sampler and pre-combusted quartz filters. Sampling was conducted on day/night or 3 h basis in the period from 29 May to 28 June 2006 during the field burning of wheat straw residue and the post-burning season. The filter samples were analyzed for low-molecular-weight dicarboxylic acids, ketoacids and α-dicarbonyls using capillary gas chromatography (GC and GC-MS employing water extraction and butyl ester derivatization. Molecular distributions of dicarboxylic acids (C2-C11, 220–6070 ng m−3 were characterized by a predominance of oxalic (C2 acid (105–3920 ng m−3 followed by succinic (C4 or malonic (C3 acid. Unsaturated aliphatic diacids, including maleic (M, isomaleic (iM and fumaric (F acids, were also detected together with aromatic diacids (phthalic, isophthalic and terephthalic acids. ω-oxocarboxylic acids (C2-C9, 24–610 ng m−3 were detected as the second most abundant compound class with the predominance of glyoxylic acid (11–360 ng m−3, followed by α-ketoacid (pyruvic acid, 3–140 ng m−3 and α-dicarbonyls (glyoxal, 1–230 ng m−3 and methylglyoxal, 2–120 ng m−3. We found that these levels (>6000 ng m−3 for diacids are several times higher than those reported in Chinese megacities at ground levels. The concentrations of diacids increased from late May to early June, showing a maximum on 7 June, and then significantly decreased during the period 8–11 June, when the wind direction shifted from southerly to northerly. Similar temporal trends were found for ketocarboxylic acids and α-dicarbonyls as well as total carbon (TC and water-soluble organic carbon (WSOC. The temporal variations of water-soluble organics were interpreted by the direct emission from the field burning of agricultural wastes (wheat straw in the North China Plain and the

  18. A High Rate Tension Device for Characterizing Brain Tissue

    CERN Document Server

    Rashid, Badar; Gilchrist, Michael; 10.1177/1754337112436900

    2013-01-01

    The mechanical characterization of brain tissue at high loading velocities is vital for understanding and modeling Traumatic Brain Injury (TBI). The most severe form of TBI is diffuse axonal injury (DAI) which involves damage to individual nerve cells (neurons). DAI in animals and humans occurs at strains > 10% and strain rates > 10/s. The mechanical properties of brain tissues at these strains and strain rates are of particular significance, as they can be used in finite element human head models to accurately predict brain injuries under different impact conditions. Existing conventional tensile testing machines can only achieve maximum loading velocities of 500 mm/min, whereas the Kolsky bar apparatus is more suitable for strain rates > 100/s. In this study, a custom-designed high rate tension device is developed and calibrated to estimate the mechanical properties of brain tissue in tension at strain rates < 90/s, while maintaining a uniform velocity. The range of strain can also be extended to 100% de...

  19. Burn Injuries: Burn Depth, Physiopathology and Type of Burns

    Directory of Open Access Journals (Sweden)

    Kemalettin Koltka

    2011-07-01

    Full Text Available A significant burn injury is a serious and mortal event. The most important threat to life is hypovolemic shock with complex pathophysiologic mechanisms. Burn depth is classified as first, second, or third degree. Local inflammatory response results a vasodilatation and an increase in vascular permeability. A burn injury is a three dimensional ischemic wound. Zone of coagulation is the zone with maximum damage. Zone of stasis consists of damaged but viable tissues, the tissue is salvageable. In zone of hyperemia tissue perfusion is increased. At the beginning, cardiac output falls and systemic vascular resistance increases; cardiac performance improves as hypovolemia is corrected with fluid resuscitation. While cardiac output increases systemic vascular resistance falls below normal values and a hypermetabolic state develops. Pulmonary vascular resistance increases immediately after thermal injury and this is more prolonged. To avoid secondary pulmonary complications, the smallest resuscitation volume of fluids that maintains adequate tissue perfusion should be given. Changes parallel to the cardiovascular response develop in other organ systems. The reasons of burn injury can be thermal, electrical, chemical or radiation. It is important to know the exact mechanism of burn injury because of different therapies for a specific cause. In this review information about burn depth, local and systemic responses to burn injury and major causes of burn injury are presented. (Journal of the Turkish Society Intensive Care 2011; 9 Suppl:1-6

  20. Highly variable rates of genome rearrangements between hemiascomycetous yeast lineages.

    Directory of Open Access Journals (Sweden)

    2006-03-01

    Full Text Available Hemiascomycete yeasts cover an evolutionary span comparable to that of the entire phylum of chordates. Since this group currently contains the largest number of complete genome sequences it presents unique opportunities to understand the evolution of genome organization in eukaryotes. We inferred rates of genome instability on all branches of a phylogenetic tree for 11 species and calculated species-specific rates of genome rearrangements. We characterized all inversion events that occurred within synteny blocks between six representatives of the different lineages. We show that the rates of macro- and microrearrangements of gene order are correlated within individual lineages but are highly variable across different lineages. The most unstable genomes correspond to the pathogenic yeasts Candida albicans and Candida glabrata. Chromosomal maps have been intensively shuffled by numerous interchromosomal rearrangements, even between species that have retained a very high physical fraction of their genomes within small synteny blocks. Despite this intensive reshuffling of gene positions, essential genes, which cluster in low recombination regions in the genome of Saccharomyces cerevisiae, tend to remain syntenic during evolution. This work reveals that the high plasticity of eukaryotic genomes results from rearrangement rates that vary between lineages but also at different evolutionary times of a given lineage.

  1. Demonstration of a high repetition rate capillary discharge waveguide

    Energy Technology Data Exchange (ETDEWEB)

    Gonsalves, A. J., E-mail: ajgonsalves@lbl.gov; Pieronek, C.; Daniels, J.; Bulanov, S. S.; Waldron, W. L.; Mittelberger, D. E.; Leemans, W. P. [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Liu, F.; Antipov, S.; Butler, J. E. [Euclid TechLabs, Gaithersburg, Maryland 20879 (United States); Bobrova, N. A.; Sasorov, P. V. [Keldysh Institute of Applied Mathematics, Moscow (Russian Federation)

    2016-01-21

    A hydrogen-filled capillary discharge waveguide operating at kHz repetition rates is presented for parameters relevant to laser plasma acceleration (LPA). The discharge current pulse was optimized for erosion mitigation with laser guiding experiments and MHD simulation. Heat flow simulations and measurements showed modest temperature rise at the capillary wall due to the average heat load at kHz repetition rates with water-cooled capillaries, which is promising for applications of LPAs such as high average power radiation sources.

  2. Physical characteristics of the Selectron high dose rate intracavitary afterloader

    Energy Technology Data Exchange (ETDEWEB)

    Chenery, S.G.A.; Pla, M.; Podgorsak, E.B. (Royal Victoria Hospital, Montreal, Quebec (Canada); McGill Univ., Montreal, Quebec (Canada))

    1985-08-01

    The physics measurements on a Selectron high dose-rate afterloading cobalt-60 unit are reported. The installation was found to be acceptable from the standpoint of radiation safety and cost effectiveness; hospital bed space was saved as treatment could be on an outpatient basis. A source calibration 4% higher than the value stated by the manufacturer was obtained. Measurement of the ratio of exposure rate in water to that in air confirmed the calibration and the applicability of correction factors for routine clinical dosimetry recommended in the literature.

  3. Nanocrystalline silicon prepared at high growth rate using helium dilution

    Indian Academy of Sciences (India)

    Koyel Bhattacharya; Debajyoti Das

    2008-06-01

    Growth and optimization of the nanocrystalline silicon (nc-Si : H) films have been studied by varying the electrical power applied to the helium diluted silane plasma in RF glow discharge. Wide optical gap and conducting intrinsic nanocrystalline silicon network of controlled crystalline volume fraction and oriented crystallographic lattice planes have been obtained at a reasonably high growth rate from helium diluted silane plasma, without using hydrogen. Improving crystallinity in the network comprising ∼ 10 nm Si-nanocrystallites and contributing optical gap widening, conductivity ascending and that obtained during simultaneous escalation of the deposition rate, promises significant technological impact.

  4. Observing the Peripheral Burning of Cigarettes by an Infrared Technique

    Directory of Open Access Journals (Sweden)

    Liu C

    2014-12-01

    Full Text Available A modern infrared camera was used to observe the peripheral burning of cigarettes during puffing and smouldering. The computer-controlled infrared system captured thermal images with recording rates up to 50 Hz at 8-bit (256-colour resolution. The response time was less than 0.04 s at ca. 780 °C. The overall performance of the system was superior to most infrared systems used in previously reported investigations. The combined capacity allowed us to capture some faster, smaller high-temperature burning events on the periphery of a cigarette during puffing, which was first described by Egertion et al. in 1963 using an X-ray method. These transient burning events were caused by tobacco shreds near the coal surface experiencing the maximum air influx. The temperature of these transient burning events could be ca. 200 to 250 °C higher than the average peripheral temperature of the cigarette. The likelihood of these high-temperature burning events occurring during smouldering was significantly less. Some other details of the cigarette's combustion were also observed with improved simplicity and clarity.

  5. Emergency in Burn; Burn in Emergency

    Directory of Open Access Journals (Sweden)

    Yalcin Bayram

    2012-06-01

    Full Text Available Physicians who first meet with burned patients are often emergency service employees. When the patient was admitted to emergency service, especially in patients with major burn injury, is a matter should be dealt with strongly. Before sending the patients to a burn center, some interventions could became life saving which should be done as a first line treatment. Herein, review of the literature related to emergency burn treatment was performed and presented to all physicians as a summary guide. In addition, some questions such as how should be physician, who first meet with the burned patient, evaluated the patient, what should be physician paid attention, which principles should be employed for fluid replacement, how should be approached to burn wound are tried to be addressed. [TAF Prev Med Bull 2012; 11(3.000: 365-368

  6. How Does the Freezer Burn Our Food?

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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.

  8. Determination of Tensile Properties of Polymers at High Strain Rates

    Directory of Open Access Journals (Sweden)

    Major Z.

    2010-06-01

    Full Text Available In the field of high rate testing of polymers the measured properties are highly dependent on the applied methodology. Hence, the test setup as whole but in particular also the geometrical type of specimen plays a decisive role. The widely used standard for the determination of tensile properties of polymers (ISO527-2 was extended by a novel standard (ISO18872:2007, which is targeted on the determination of tensile properties at high strain rates. In this standard also a novel specimen shape is proposed. Hand in hand with the introduction of new specimen geometry the question of comparability arises. To point out the differences in stress-strain response of the ISO18872 specimen and the ISO527-2 multipurpose specimen tensile tests over a wide loading rate range were conducted in this paper. A digital image correlation system in combination with a high speed camera was used to characterize the local material behaviour. Different parameters like nominal stress, true stress, nominal strain, true strain as well as volumetric strain were determined and used to compare the two specimen geometries.

  9. Multiplexed CV quantum teleportation for high rates in quantum communication

    CERN Document Server

    Christ, Andreas; Silberhorn, Christine

    2012-01-01

    A major challenge of today's quantum communication systems lies in the transmission of quantum information with high rates over long distances in the presence of unavoidable losses. Thereby the achievable quantum communication rate is fundamentally limited by the amount of energy that can be transmitted per use of the channel. It is hence vital to develop quantum communication protocols which encode quantum information as energy efficiently as possible. To this aim we investigate continuous-variable quantum teleportation as a method of distributing quantum information. We explore the possibility to encode information on multiple optical modes and derive upper and lower bounds on the achievable quantum channel capacities. This analysis enables us to benchmark single-mode vs. multi-mode entanglement resources. Our research reveals that multiplexing does not only feature an enhanced energy efficiency, significantly increasing the achievable quantum communication rates in comparison to single-mode coding, but als...

  10. High data rate recording: Moving to 2 Gbit/s

    Science.gov (United States)

    Taratorin, A.; Yuan, S.; Nikitin, V.

    2003-05-01

    High data rate recording can be achieved using fast write drivers and fast heads. Advanced short-yoke write heads and write drivers with 450 ps rise time and programmable current overshoot were used to study recording at data rates up to 2 Gbit/s. The head flux rise time causes shifts of recorded transitions. It is well known that current overshoot helps to overcome bandwidth limitations in the write driver, interconnects, and write head. However, excessive overshoot may cause pattern-dependent transition shifts and significant distortions of recorded transitions. We present the data rate performance of short-yoke recording heads, analysis of nonlinear pattern-dependent distortions, and optimization of the write current wave form in the 1-2 Gbit/s range. Simple dibit and tribit patterns were recorded at 2 Gbit/s. Low-distortion recording for arbitrary data patterns was demonstrated at 1.6 Gbit/s after optimization of write current overshoot.

  11. Dynamic High-Temperature Characterization of an Iridium Alloy in Compression at High Strain Rates

    Energy Technology Data Exchange (ETDEWEB)

    Song, Bo [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Experimental Environment Simulation Dept.; Nelson, Kevin [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Mechanics of Materials Dept.; Lipinski, Ronald J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Advanced Nuclear Fuel Cycle Technology Dept.; Bignell, John L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Structural and Thermal Analysis Dept.; Ulrich, G. B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Radioisotope Power Systems Program; George, E. P. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Radioisotope Power Systems Program

    2014-06-01

    Iridium alloys have superior strength and ductility at elevated temperatures, making them useful as structural materials for certain high-temperature applications. However, experimental data on their high-temperature high-strain-rate performance are needed for understanding high-speed impacts in severe elevated-temperature environments. Kolsky bars (also called split Hopkinson bars) have been extensively employed for high-strain-rate characterization of materials at room temperature, but it has been challenging to adapt them for the measurement of dynamic properties at high temperatures. Current high-temperature Kolsky compression bar techniques are not capable of obtaining satisfactory high-temperature high-strain-rate stress-strain response of thin iridium specimens investigated in this study. We analyzed the difficulties encountered in high-temperature Kolsky compression bar testing of thin iridium alloy specimens. Appropriate modifications were made to the current high-temperature Kolsky compression bar technique to obtain reliable compressive stress-strain response of an iridium alloy at high strain rates (300 – 10000 s-1) and temperatures (750°C and 1030°C). Uncertainties in such high-temperature high-strain-rate experiments on thin iridium specimens were also analyzed. The compressive stress-strain response of the iridium alloy showed significant sensitivity to strain rate and temperature.

  12. Investigation of high-rate lithium-thionyl chloride cells

    Science.gov (United States)

    Hayes, Catherine A.; Gust, Steven; Farrington, Michael D.; Lockwood, Judith A.; Donaldson, George J.

    Chemical analysis of a commercially produced high-rate D-size lithium-thionyl cell was carried out, as a function of rate of discharge (1 ohm and 5 ohms), depth of discharge, and temperature (25 C and -40 C), using specially developed methods for identifying suspected minor cell products or impurities which may effect cell performance. These methods include a product-retrieval system which involves solvent extraction to enhance the recovery of suspected semivolatile minor chemicals, and methods of quantitative GC analysis of volatile and semivolatile products. The nonvolatile products were analyzed by wet chemical methods. The results of the analyses indicate that the predominant discharge reaction in this cell is 4Li + 2SOCl2 going to 4LiCl + S + SO2, with SO2 formation decreasing towards the end of cell life (7 to 12 Ah). The rate of discharge had no effect on the product distribution. Upon discharge of the high-rate cell at -40 C, one cell exploded, and all others exhibited overheating and rapid internal pressure rise when allowed to warm up to room temperature.

  13. HIGH RATES OF EVOLUTION PRECEDED THE ORIGIN OF BIRDS

    Science.gov (United States)

    Puttick, Mark N; Thomas, Gavin H; Benton, Michael J; Polly, P David

    2014-01-01

    The origin of birds (Aves) is one of the great evolutionary transitions. Fossils show that many unique morphological features of modern birds, such as feathers, reduction in body size, and the semilunate carpal, long preceded the origin of clade Aves, but some may be unique to Aves, such as relative elongation of the forelimb. We study the evolution of body size and forelimb length across the phylogeny of coelurosaurian theropods and Mesozoic Aves. Using recently developed phylogenetic comparative methods, we find an increase in rates of body size and body size dependent forelimb evolution leading to small body size relative to forelimb length in Paraves, the wider clade comprising Aves and Deinonychosauria. The high evolutionary rates arose primarily from a reduction in body size, as there were no increased rates of forelimb evolution. In line with a recent study, we find evidence that Aves appear to have a unique relationship between body size and forelimb dimensions. Traits associated with Aves evolved before their origin, at high rates, and support the notion that numerous lineages of paravians were experimenting with different modes of flight through the Late Jurassic and Early Cretaceous. PMID:24471891

  14. High frame rate measurements of semiconductor pixel detector readout IC

    Science.gov (United States)

    Szczygiel, R.; Grybos, P.; Maj, P.

    2012-07-01

    We report on high count rate and high frame rate measurements of a prototype IC named FPDR90, designed for readouts of hybrid pixel semiconductor detectors used for X-ray imaging applications. The FPDR90 is constructed in 90 nm CMOS technology and has dimensions of 4 mm×4 mm. Its main part is a matrix of 40×32 pixels with 100 μm×100 μm pixel size. The chip works in the single photon counting mode with two discriminators and two 16-bit ripple counters per pixel. The count rate per pixel depends on the effective CSA feedback resistance and can be set up to 6 Mcps. The FPDR90 can operate in the continuous readout mode, with zero dead time. Due to the architecture of digital blocks in pixel, one can select the number of bits read out from each counter from 1 to 16. Because in the FPDR90 prototype only one data output is available, the frame rate is 9 kfps and 72 kfps for 16 bits and 1 bit readout, respectively (with nominal clock frequency of 200 MHz).

  15. High frame rate measurements of semiconductor pixel detector readout IC

    Energy Technology Data Exchange (ETDEWEB)

    Szczygiel, R., E-mail: robert.szczygiel@agh.edu.pl [AGH University of Science and Technology, Department of Measurement and Instrumentation, Al. Mickiewicza 30, 30-059 Cracow (Poland); Grybos, P.; Maj, P. [AGH University of Science and Technology, Department of Measurement and Instrumentation, Al. Mickiewicza 30, 30-059 Cracow (Poland)

    2012-07-11

    We report on high count rate and high frame rate measurements of a prototype IC named FPDR90, designed for readouts of hybrid pixel semiconductor detectors used for X-ray imaging applications. The FPDR90 is constructed in 90 nm CMOS technology and has dimensions of 4 mm Multiplication-Sign 4 mm. Its main part is a matrix of 40 Multiplication-Sign 32 pixels with 100 {mu}m Multiplication-Sign 100 {mu}m pixel size. The chip works in the single photon counting mode with two discriminators and two 16-bit ripple counters per pixel. The count rate per pixel depends on the effective CSA feedback resistance and can be set up to 6 Mcps. The FPDR90 can operate in the continuous readout mode, with zero dead time. Due to the architecture of digital blocks in pixel, one can select the number of bits read out from each counter from 1 to 16. Because in the FPDR90 prototype only one data output is available, the frame rate is 9 kfps and 72 kfps for 16 bits and 1 bit readout, respectively (with nominal clock frequency of 200 MHz).

  16. Small cryptopredators contribute to high predation rates on coral reefs

    Science.gov (United States)

    Goatley, Christopher H. R.; González-Cabello, Alonso; Bellwood, David R.

    2017-03-01

    Small fishes suffer high mortality rates on coral reefs, primarily due to predation. Although studies have identified the predators of early post-settlement fishes, the predators of small cryptobenthic fishes remain largely unknown. We therefore used a series of mesocosm experiments with natural habitat and cryptobenthic fish communities to identify the impacts of a range of small potential predators, including several invertebrates, on prey fish populations. While there was high variability in predation rates, many members of the cryptobenthic fish community act as facultative cryptopredators, being prey when small and piscivores when larger. Surprisingly, we also found that smashing mantis shrimps may be important fish predators. Our results highlight the diversity of the predatory community on coral reefs and identify previously unknown trophic links in these complex ecosystems.

  17. Complex pulsing schemes for high frame rate imaging

    DEFF Research Database (Denmark)

    Misaridis, Thanassis; Fink, Mathias; Jensen, Jørgen Arendt

    2002-01-01

    High frame rate ultrasound imaging can be achieved by simultaneous transmission of multiple focused beams along different directions. However, image quality degrades by the interference among beams. An alternative approach is to transmit spherical waves of a basic short pulse with frequency coding...... with linear frequency modulation along the transducer elements, that cover the 70% fractional bandwidth of the 7 MHz transducer. The resulted images (after beamforming and matched filtering) show an axial resolution at the same order as in conventional pulse excitation and axial sidelobes down to -45 d......B. With the proposed imaging strategy of pulse train excitation, a whole image can be formed with only two emissions, making it possible to obtain high quality images at a frame rate of 20 to 25 times higher than that of conventional phased array imaging...

  18. Characteristics of Multiplexed Grooved Nozzles for High Flow Rate Electrospray

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyoung Tae; Kim, Woo Jin; Kim, Sang Soo [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2007-10-15

    The electrospray operated in the cone-jet mode can generate highly charged micro droplets in an almost uniform size at flow rates. Therefore, the multiplexing system which can retain the characteristics of the cone-jet mode is inevitable for the electrospray application. This experiment reports the multiplexed grooved nozzle system with the extractor. The effects of the grooves and the extractor on the performance of the electrospray were evaluated through experiments. Using the grooved nozzle, the stable cone-jet mode can be achieved at the each groove in the grooved mode. Furthermore, the number of nozzles per unit area is increased by the extractor. The multiplexing density is 12 jets per cm{sup 2} at 30 mm distance from the nozzle tip to the ground plate. The multiplexing system for the high flow rate electrospray is realized with the extractor which can diminish the space charge effect without sacrificing characteristics of the cone-jet mode.

  19. Brazil Fire Characterization and Burn Area Estimation Using the Airborne Infrared Disaster Assessment (AIRDAS) System

    Science.gov (United States)

    Brass, J. A.; Riggan, P. J.; Ambrosia, V. G.; Lockwood, R. N.; Pereira, J. A.; Higgins, R. G.; Peterson, David L. (Technical Monitor)

    1995-01-01

    Remotely sensed estimations of regional and global emissions from biomass combustion have been used to characterize fire behavior, determine fire intensity, and estimate burn area. Highly temporal, low resolution satellite data have been used to calculate estimates of fire numbers and area burned. These estimates of fire activity and burned area have differed dramatically, resulting in a wide range of predictions on the ecological and environmental impacts of fires. As part of the Brazil/United States Fire Initiative, an aircraft campaign was initiated in 1992 and continued in 1994. This multi-aircraft campaign was designed to assist in the characterization of fire activity, document fire intensity and determine area burned over prescribed, agricultural and wildland fires in the savanna and forests of central Brazil. Using a unique, multispectral scanner (AIRDAS), designed specifically for fire characterization, a variety of fires and burned areas were flown with a high spatial and high thermal resolution scanner. The system was used to measure flame front size, rate of spread, ratio of smoldering to flaming fronts and fire intensity. In addition, long transects were flown to determine the size of burned areas within the cerrado and transitional ecosystems. The authors anticipate that the fire activity and burned area estimates reported here will lead to enhanced information for precise regional trace gas prediction.

  20. Distribution of streaming rates into high-redshift galaxies

    CERN Document Server

    Goerdt, Tobias; Dekel, Avishai; Teyssier, Romain

    2015-01-01

    We study the accretion along streams from the cosmic web into high-redshift massive galaxies using three sets of AMR hydro-cosmological simulations. We find that the streams keep a roughly constant accretion rate as they penetrate into the halo centre. The mean accretion rate follows the mass and redshift dependence predicted for haloes by the EPS approximation, dM / dt is proportional to Mvir^{1.25} (1 + z)^{2.5}. The distribution of the accretion rates can well be described by a sum of two Gaussians, the primary corresponding to "smooth inflow" and the secondary to "mergers". The same functional form was already found for the distributions of specific star formation rates in observations. The mass fraction in the smooth component is 60 - 90 %, insensitive to redshift or halo mass. The simulations with strong feedback show clear signs of re-accretion due to recycling of galactic winds. The mean accretion rate for the mergers is a factor 2 - 3 larger than that of the smooth component. The standard deviation o...

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

    Science.gov (United States)

    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.

  2. High-rate diamond deposition by microwave plasma CVD

    Science.gov (United States)

    Li, Xianglin

    In this dissertation, the growth of CVD (Chemical Vapor Deposition) diamond thin films is studied both theoretically and experimentally. The goal of this research is to deposit high quality HOD (Highly Oriented Diamond) films with a growth rate greater than 1 mum/hr. For the (100)-oriented HOD films, the growth rate achieved by the traditional process is only 0.3 mum/hr while the theoretical limit is ˜0.45 mum/hr. This research increases the growth rate up to 5.3 mum/hr (with a theoretical limit of ˜7 mum/hr) while preserving the crystal quality. This work builds a connection between the theoretical study of the CVD process and the experimental research. The study is extended from the growth of regular polycrystalline diamond to highly oriented diamond (HOD) films. For the increase of the growth rate of regular polycrystalline diamond thin films, a scaling growth model developed by Goodwin is introduced in details to assist in the understanding of the MPCVD (Microwave Plasma CVD) process. Within the Goodwin's scaling model, there are only four important sub-processes for the growth of diamond: surface modification, adsorption, desorption, and incorporation. The factors determining the diamond growth rate and film quality are discussed following the description of the experimental setup and process parameters. Growth rate and crystal quality models are reviewed to predict and understand the experimental results. It is shown that the growth rate of diamond can be increased with methane input concentration and the amount of atomic hydrogen (by changing the total pressure). It is crucial to provide enough atomic hydrogen to conserve crystal quality of the deposited diamond film. The experimental results demonstrate that for a fixed methane concentration, there is a minimum pressure for growth of good diamond. Similarly, for a fixed total pressure, there is a maximum methane concentration for growth of good diamond, and this maximum methane concentration increases

  3. High Strain Rate Experiments of Energetic Material Binder

    OpenAIRE

    Rangel Mendoza, Roberto; Harr, Michael; Chen, Weinong

    2016-01-01

    Energetic materials, in particular HMX, is widely used in many applications as polymer bonded explosives (PBX) and rocket propellant. However, when damaged, HMX is known to be an unstable substance which renders it a hazardous material and in some cases unreliable. Finding critical mechanical conditions at high rates that render various forms of energetic materials as unreliable would be vital to understand the effects that vibrations and compression forces have on energetic materials. A bett...

  4. Fast demographic traits promote high diversification rates of Amazonian trees

    OpenAIRE

    Baker, Timothy R.; Pennington, R. Toby; Magallon, Susana; Gloor, Emanuel; Laurance, William F.; Alexiades, Miguel; Alvarez, Esteban; Araujo, Alejandro; Arets, Eric J. M. M.; Aymard, Gerardo; de Oliveira, Atila Alves; Amaral, Iêda; Arroyo, Luzmila; Bonal, Damien; Roel J.W. Brienen

    2014-01-01

    The Amazon rain forest sustains the world's highest tree diversity, but it remains unclear why some clades of trees are hyperdiverse, whereas others are not. Using dated phylogenies, estimates of current species richness and trait and demographic data from a large network of forest plots, we show that fast demographic traits - short turnover times - are associated with high diversification rates across 51 clades of canopy trees. This relationship is robust to assuming that diversification rat...

  5. Data Feature Extraction for High-Rate 3-Phase Data

    Energy Technology Data Exchange (ETDEWEB)

    2016-10-18

    This algorithm processes high-rate 3-phase signals to identify the start time of each signal and estimate its envelope as data features. The start time and magnitude of each signal during the steady state is also extracted. The features can be used to detect abnormal signals. This algorithm is developed to analyze Exxeno's 3-phase voltage and current data recorded from refrigeration systems to detect device failure or degradation.

  6. High rate multiplicity detector for relativistic heavy-ion collisions

    Energy Technology Data Exchange (ETDEWEB)

    Beavis, D. [Brookhaven National Lab., Upton, NY (United States); Bennett, M.J. [Yale University, A.W. Wright Nuclear Structure Laboratory, New Haven, CT 06511 (United States); Carroll, J.B. [University of California at Los Angeles, Los Angeles, CA (United States); Chiba, J. [KEK National High Energy Physics, Tsukuba (Japan); Chikanian, A. [Yale University, A.W. Wright Nuclear Structure Laboratory, New Haven, CT 06511 (United States); Crawford, H.J. [University of California Space Sciences Laboratory, Berkeley, CA (United States); Cronqvist, M. [University of California Space Sciences Laboratory, Berkeley, CA (United States); Dardenne, Y. [University of California Space Sciences Laboratory, Berkeley, CA (United States); Debbe, R. [Brookhaven National Lab., Upton, NY (United States); Doke, T. [Waseda University, Science and Engineering Research Institute, Waseda (Japan); Engelage, J. [University of California Space Sciences Laboratory, Berkeley, CA (United States); Flores, I. [University of California Space Sciences Laboratory, Berkeley, CA (United States); Greiner, L. [University of California Space Sciences Laboratory, Berkeley, CA (United States); Hayano, R.S. [University of Tokyo, Tokyo (Japan); Hallman, T.J. [University of California at Los Angeles, Los Angeles, CA (United States); Heckman, H.H. [Lawrence Berkeley Lab., CA (United States); Kashiwagi, T. [Waseda University, Science and Engineering Research Institute, Waseda (Japan); Kikuchi, J. [Waseda University, Science and Engineering Research Institute, Waseda (Japan); Kumar, B.S. [Yale University, A.W. Wright Nuclear Structure Laboratory, New Haven, CT 06511 (United States); Kuo, C. [University of California Space Sciences Laboratory, Berkeley, CA (United States); Lindstrom, P.J. [Lawrence Berkeley Lab., CA (United States); Mitchell, J.W. [Universities Space Research Association/Goddard Space Flight Center, Greenbelt, MD (United States); Nagamiya, S.; E878 Collaboration

    1995-04-21

    We have constructed and operated a detector to measure the multiplicity of secondary particles produced in nucleus-nucleus collisions in the E878 experiment at the Brookhaven National Laboratory AGS facility. We describe the operation and performance of the detector in a high rate Au beam environment, and interpret the multiplicity data in terms of the impact parameters of the nucleus-nucleus collisions. ((orig.)).

  7. High-rate measurement-device-independent quantum cryptography

    DEFF Research Database (Denmark)

    Pirandola, Stefano; Ottaviani, Carlo; Spedalieri, Gaetana

    2015-01-01

    Quantum cryptography achieves a formidable task - the remote distribution of secret keys by exploiting the fundamental laws of physics. Quantum cryptography is now headed towards solving the practical problem of constructing scalable and secure quantum networks. A significant step in this direction...... than those currently achieved. Our protocol could be employed to build high-rate quantum networks where devices securely connect to nearby access points or proxy servers....

  8. Twinning in copper deformed at high strain rates

    Indian Academy of Sciences (India)

    S Cronje; R E Kroon; W D Roos; J H Neethling

    2013-02-01

    Copper samples having varying microstructures were deformed at high strain rates using a split-Hopkinson pressure bar. Transmission electron microscopy results show deformation twins present in samples that were both annealed and strained, whereas samples that were annealed and left unstrained, as well as samples that were unannealed and strained, are devoid of these twins. These deformation twins occurred at deformation conditions less extreme than previously predicted.

  9. MDT Performance in a High Rate Background Environment

    CERN Document Server

    Aleksa, Martin; Hessey, N P; Riegler, W

    1998-01-01

    A Cs137 gamma source with different lead filters in the SPS beam-line X5 has been used to simulate the ATLAS background radiation. This note shows the impact of high background rates on the MDT efficiency and resolution for three kinds of pulse shaping and compares the results with GARFIELD simulations. Furthermore it explains how the performance can be improved by time slewing corrections and double track separation.

  10. Respiratory health concerns in children at some strategic locations from high PM levels during crop residue burning episodes

    Science.gov (United States)

    Gupta, Sachin; Agarwal, Ravinder; Mittal, Susheel K.

    2016-07-01

    Particulate Matter (PM) levels in the ambient air of three urban sites of strategic importance in Punjab (second largest agricultural state of India) were monitored from September 2013 to June 2014 covering two seasons of crop residue burning episodes of rice and wheat, respectively. During both crop periods, the levels varied from 71 to 167 μgm-3(PM10) and 43-107 μgm-3 (PM2.5), which were observed to be much beyond the permissible limits of 100 μgm-3 for PM10 and 60 μgm-3 for PM2.5 set by state pollution control agencies. Simultaneously, Pulmonary Function Test (PFT) parameters of children (age group 10-16 years) residing at these sites were monitored. PFT parameters like Forced Vital Capacity (FVC) and Peak Expiratory Flow (PEF) were monitored on 50 healthy subjects at each site. The results indicated an alarming fall in FVC (5%-7%) and in PEF (4%-6%) parameters during the crop residue burning period's .The decrement was almost same for all age groups of children. The adverse effect was more on female subjects than male subjects. The impact of particulate matter pollution was more prominent in industrially important site (7%, SIS) as compared to historically (3%, HIS) and commercially (4%, CAS) important sites.

  11. Mechanical properties of transgenic silkworm silk at high rate impact

    Science.gov (United States)

    Chu, Jou-Mei

    Transgenic silkworm silk was created to obtain the quality of spider silk while being mass-producible. Due to the variability in sequencing between the silkworm and spider DNA, the resulting transgenic silkworm silk may have different properties compared to spider silk. Furthermore, the high strain rate mechanical response of this new natural fiber is still unknown and needs to be characterized. In this experimental research, a quasi-static load frame (MTS) and a Kolsky tension bar are used to characterize the tensile stress-strain response of transgenic silkworm silk over a range of strain-rates between 10-3/s to 103/s. The results show that transgenic silkworm silk tends to have high overall elongation and initial stiffness at high strain rates compared to those of spider silk. Furthermore, specimen gage length sensitivity is studied with gage lengths of 3.97 mm (5/32 in), 4.76 mm (3/16 in), and 6.35 mm (1/4 in). Fracture surfaces are examined via Scanning Electron Microscopy (SEM) and reveal that the fracture mode is similar to that of spider silk. Therefore, it may be possible for the tensile properties of transgenic silkworm silk be comparable to that of spider silk.

  12. Semi-solid electrodes having high rate capability

    Science.gov (United States)

    Chiang, Yet-Ming; Duduta, Mihai; Holman, Richard; Limthongkul, Pimpa; Tan, Taison

    2016-06-07

    Embodiments described herein relate generally to electrochemical cells having high rate capability, and more particularly to devices, systems and methods of producing high capacity and high rate capability batteries having relatively thick semi-solid electrodes. In some embodiments, an electrochemical cell includes an anode and a semi-solid cathode. The semi-solid cathode includes a suspension of an active material of about 35% to about 75% by volume of an active material and about 0.5% to about 8% by volume of a conductive material in a non-aqueous liquid electrolyte. An ion-permeable membrane is disposed between the anode and the semi-solid cathode. The semi-solid cathode has a thickness of about 250 .mu.m to about 2,000 .mu.m, and the electrochemical cell has an area specific capacity of at least about 7 mAh/cm.sup.2 at a C-rate of C/4. In some embodiments, the semi-solid cathode slurry has a mixing index of at least about 0.9.

  13. Atomistic simulations of high strain rate loading of nanocrystals

    Science.gov (United States)

    Bringa, E. M.; Tramontina, D.; Ruestes, C. J.; Tang, Y.; Meyers, M. A.; Gunkelmann, N.; Urbassek, H. M.

    2013-03-01

    Materials loaded at high strain rates can reach extreme temperature and pressure conditions. Most experiments on loading of simple materials use poly crystals, while most atomistic simulations of shock wave loading deal with single crystals, due to the higher computational cost of running polycrystal samples. Of course, atomistic simulations of polycrystals with micron-sized grains are beyond the capabilities of current supercomputers. On the other hand, nanocrystals (nc) with grain sizes below 50 nm can be obtained experimentally and modeled reasonably well at high strain rates, opening the possibility of nearly direct comparison between atomistic molecular dynamics (MD) simulations and experiments using high power lasers. We will discuss MD simulations and links to experiments for nc Cu and Ni, as model f.c.c. solids, and nc Ta and Fe, as model b.c.c. solids. In all cases, the microstructure resulting from loading depends strongly on grain size, strain rate and peak applied pressure. We will also discuss effects related to target porosity in nc's. E.M.B. thanks funding from PICT2008-1325.

  14. High-rate electrochemical energy storage through Li+ intercalation pseudocapacitance.

    Science.gov (United States)

    Augustyn, Veronica; Come, Jérémy; Lowe, Michael A; Kim, Jong Woung; Taberna, Pierre-Louis; Tolbert, Sarah H; Abruña, Héctor D; Simon, Patrice; Dunn, Bruce

    2013-06-01

    Pseudocapacitance is commonly associated with surface or near-surface reversible redox reactions, as observed with RuO2·xH2O in an acidic electrolyte. However, we recently demonstrated that a pseudocapacitive mechanism occurs when lithium ions are inserted into mesoporous and nanocrystal films of orthorhombic Nb2O5 (T-Nb2O5; refs 1,2). Here, we quantify the kinetics of charge storage in T-Nb2O5: currents that vary inversely with time, charge-storage capacity that is mostly independent of rate, and redox peaks that exhibit small voltage offsets even at high rates. We also define the structural characteristics necessary for this process, termed intercalation pseudocapacitance, which are a crystalline network that offers two-dimensional transport pathways and little structural change on intercalation. The principal benefit realized from intercalation pseudocapacitance is that high levels of charge storage are achieved within short periods of time because there are no limitations from solid-state diffusion. Thick electrodes (up to 40 μm thick) prepared with T-Nb2O5 offer the promise of exploiting intercalation pseudocapacitance to obtain high-rate charge-storage devices.

  15. Increased admissions for diabetes mellitus after burn.

    Science.gov (United States)

    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 (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 admissions for diabetes mellitus during this time. Results would suggest prolonged clinical management after discharge and or wound healing to minimise post-burn admissions for diabetes mellitus is required. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

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

    Science.gov (United States)

    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.

  17. High Strain Rate Compression Testing of Ceramics and Ceramic Composites.

    Energy Technology Data Exchange (ETDEWEB)

    Blumenthal, W. R. (William R.)

    2005-01-01

    The compressive deformation and failure behavior of ceramics and ceramic-metal composites for armor applications has been studied as a function of strain rate at Los Alamos National Laboratory since the late 1980s. High strain rate ({approx}10{sup 3} s{sup -1}) uniaxial compression loading can be achieved using the Kolsky-split-Hopkinson pressure bar (SHPB) technique, but special methods must be used to obtain valid strength results. This paper reviews these methods and the limitations of the Kolsky-SHPB technique for this class of materials. The Kolsky-split-Hopkinson pressure bar (Kolsky-SHPB) technique was originally developed to characterize the mechanical behavior of ductile materials such as metals and polymers where the results can be used to develop strain-rate and temperature-dependent constitutive behavior models that empirically describe macroscopic plastic flow. The flow behavior of metals and polymers is generally controlled by thermally-activated and rate-dependent dislocation motion or polymer chain motion in response to shear stresses. Conversely, the macroscopic mechanical behavior of dense, brittle, ceramic-based materials is dominated by elastic deformation terminated by rapid failure associated with the propagation of defects in the material in response to resolved tensile stresses. This behavior is usually characterized by a distribution of macroscopically measured failure strengths and strains. The basis for any strain-rate dependence observed in the failure strength must originate from rate-dependence in the damage and fracture process, since uniform, uniaxial elastic behavior is rate-independent (e.g. inertial effects on crack growth). The study of microscopic damage and fracture processes and their rate-dependence under dynamic loading conditions is a difficult experimental challenge that is not addressed in this paper. The purpose of this paper is to review the methods that have been developed at the Los Alamos National Laboratory to

  18. Scale dependence of rock friction at high work rate.

    Science.gov (United States)

    Yamashita, Futoshi; Fukuyama, Eiichi; Mizoguchi, Kazuo; Takizawa, Shigeru; Xu, Shiqing; Kawakata, Hironori

    2015-12-10

    Determination of the frictional properties of rocks is crucial for an understanding of earthquake mechanics, because most earthquakes are caused by frictional sliding along faults. Prior studies using rotary shear apparatus revealed a marked decrease in frictional strength, which can cause a large stress drop and strong shaking, with increasing slip rate and increasing work rate. (The mechanical work rate per unit area equals the product of the shear stress and the slip rate.) However, those important findings were obtained in experiments using rock specimens with dimensions of only several centimetres, which are much smaller than the dimensions of a natural fault (of the order of 1,000 metres). Here we use a large-scale biaxial friction apparatus with metre-sized rock specimens to investigate scale-dependent rock friction. The experiments show that rock friction in metre-sized rock specimens starts to decrease at a work rate that is one order of magnitude smaller than that in centimetre-sized rock specimens. Mechanical, visual and material observations suggest that slip-evolved stress heterogeneity on the fault accounts for the difference. On the basis of these observations, we propose that stress-concentrated areas exist in which frictional slip produces more wear materials (gouge) than in areas outside, resulting in further stress concentrations at these areas. Shear stress on the fault is primarily sustained by stress-concentrated areas that undergo a high work rate, so those areas should weaken rapidly and cause the macroscopic frictional strength to decrease abruptly. To verify this idea, we conducted numerical simulations assuming that local friction follows the frictional properties observed on centimetre-sized rock specimens. The simulations reproduced the macroscopic frictional properties observed on the metre-sized rock specimens. Given that localized stress concentrations commonly occur naturally, our results suggest that a natural fault may lose its

  19. Brachytherapy for early oral tongue cancer. Low dose rate to high dose rate

    Energy Technology Data Exchange (ETDEWEB)

    Yamazaki, Hideya [Toyonaka Municipal Hospital, Osaka (Japan); Inoue, Takehiro; Yoshida, Ken; Yoshioka, Yasuo; Shimizutani, Kimishige; Inoue, Toshihiko [Osaka Univ., Suita (Japan). Graduate School of Medicine; Furukawa, Souhei; Kakimoto, Naoya [Osaka Univ., Suita (Japan). Graduate School of Dentistry

    2003-03-01

    To examine the compatibility of low dose rate (LDR) with high dose rate (HDR) brachytherapy, we reviewed 399 patients with early oral tongue cancer (T1-2N0M0) treated solely by brachytherapy at Osaka University Hospital between 1967 and 1999. For patients in the LDR group (n=341), the treatment sources consisted of Ir-192 pin for 227 patients (1973-1996; irradiated dose, 61-85 Gy; median, 70 Gy), Ra-226 needle for 113 patients (1967-1986; 55-93 Gy; median, 70 Gy). Ra-226 and Ir-192 were combined for one patient. Ir-192 HDR (microSelectron-HDR) was used for 58 patients in the HDR group (1991-present; 48-60 Gy; median, 60 Gy). LDR implantations were performed via oral and HDR via a submental/submandibular approach. The dose rates at the reference point for the LDR group were 0.30 to 0.8 Gy/h, and for the HDR group 1.0 to 3.4 Gy/min. The patients in the HDR group received a total dose of 48-60 Gy (8-10 fractions) during one week. Two fractions were administered per day (at least a 6-h interval). The 3- and 5-year local control rates for patients in the LDR group were 85% and 80%, respectively, and those in the HDR group were both 84%. HDR brachytherapy showed the same lymph-node control rate as did LDR brachytherapy (67% at 5 years). HDR brachytherapy achieved the same locoregional result as did LDR brachytherapy. A converting factor of 0.86 is applicable for HDR in the treatment of early oral tongue cancer. (author)

  20. Brachytherapy for early oral tongue cancer: low dose rate to high dose rate.

    Science.gov (United States)

    Yamazaki, Hideya; Inoue, Takehiro; Yoshida, Ken; Yoshioka, Yasuo; Furukawa, Souhei; Kakimoto, Naoya; Shimizutani, Kimishige; Inoue, Toshihiko

    2003-03-01

    To examine the compatibility of low dose rate (LDR) with high dose rate (HDR) brachytherapy, we reviewed 399 patients with early oral tongue cancer (T1-2N0M0) treated solely by brachytherapy at Osaka University Hospital between 1967 and 1999. For patients in the LDR group (n = 341), the treatment sources consisted of Ir-192 pin for 227 patients (1973-1996; irradiated dose, 61-85 Gy; median, 70 Gy), Ra-226 needle for 113 patients (1967-1986; 55-93 Gy; median, 70 Gy). Ra-226 and Ir-192 were combined for one patient. Ir-192 HDR (microSelectron-HDR) was used for 58 patients in the HDR group (1991-present; 48-60 Gy; median, 60 Gy). LDR implantations were performed via oral and HDR via a submental/submandibular approach. The dose rates at the reference point for the LDR group were 0.30 to 0.8 Gy/h, and for the HDR group 1.0 to 3.4 Gy/min. The patients in the HDR group received a total dose of 48-60 Gy (8-10 fractions) during one week. Two fractions were administered per day (at least a 6-h interval). The 3- and 5-year local control rates for patients in the LDR group were 85% and 80%, respectively, and those in the HDR group were both 84%. HDR brachytherapy showed the same lymph-node control rate as did LDR brachytherapy (67% at 5 years). HDR brachytherapy achieved the same locoregional result as did LDR brachytherapy. A converting factor of 0.86 is applicable for HDR in the treatment of early oral tongue cancer.